File: | jdk/src/hotspot/share/opto/loopnode.cpp |
Warning: | line 577, column 15 Value stored to 'jvms' during its initialization is never read |
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1 | /* |
2 | * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved. |
3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
4 | * |
5 | * This code is free software; you can redistribute it and/or modify it |
6 | * under the terms of the GNU General Public License version 2 only, as |
7 | * published by the Free Software Foundation. |
8 | * |
9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
12 | * version 2 for more details (a copy is included in the LICENSE file that |
13 | * accompanied this code). |
14 | * |
15 | * You should have received a copy of the GNU General Public License version |
16 | * 2 along with this work; if not, write to the Free Software Foundation, |
17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
18 | * |
19 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
20 | * or visit www.oracle.com if you need additional information or have any |
21 | * questions. |
22 | * |
23 | */ |
24 | |
25 | #include "precompiled.hpp" |
26 | #include "ci/ciMethodData.hpp" |
27 | #include "compiler/compileLog.hpp" |
28 | #include "gc/shared/barrierSet.hpp" |
29 | #include "gc/shared/c2/barrierSetC2.hpp" |
30 | #include "libadt/vectset.hpp" |
31 | #include "memory/allocation.inline.hpp" |
32 | #include "memory/resourceArea.hpp" |
33 | #include "opto/addnode.hpp" |
34 | #include "opto/arraycopynode.hpp" |
35 | #include "opto/callnode.hpp" |
36 | #include "opto/castnode.hpp" |
37 | #include "opto/connode.hpp" |
38 | #include "opto/convertnode.hpp" |
39 | #include "opto/divnode.hpp" |
40 | #include "opto/idealGraphPrinter.hpp" |
41 | #include "opto/loopnode.hpp" |
42 | #include "opto/movenode.hpp" |
43 | #include "opto/mulnode.hpp" |
44 | #include "opto/opaquenode.hpp" |
45 | #include "opto/rootnode.hpp" |
46 | #include "opto/runtime.hpp" |
47 | #include "opto/superword.hpp" |
48 | #include "runtime/sharedRuntime.hpp" |
49 | #include "utilities/powerOfTwo.hpp" |
50 | |
51 | //============================================================================= |
52 | //--------------------------is_cloop_ind_var----------------------------------- |
53 | // Determine if a node is a counted loop induction variable. |
54 | // NOTE: The method is declared in "node.hpp". |
55 | bool Node::is_cloop_ind_var() const { |
56 | return (is_Phi() && |
57 | as_Phi()->region()->is_CountedLoop() && |
58 | as_Phi()->region()->as_CountedLoop()->phi() == this); |
59 | } |
60 | |
61 | //============================================================================= |
62 | //------------------------------dump_spec-------------------------------------- |
63 | // Dump special per-node info |
64 | #ifndef PRODUCT |
65 | void LoopNode::dump_spec(outputStream *st) const { |
66 | if (is_inner_loop()) st->print( "inner " ); |
67 | if (is_partial_peel_loop()) st->print( "partial_peel " ); |
68 | if (partial_peel_has_failed()) st->print( "partial_peel_failed " ); |
69 | } |
70 | #endif |
71 | |
72 | //------------------------------is_valid_counted_loop------------------------- |
73 | bool LoopNode::is_valid_counted_loop(BasicType bt) const { |
74 | if (is_BaseCountedLoop() && as_BaseCountedLoop()->bt() == bt) { |
75 | BaseCountedLoopNode* l = as_BaseCountedLoop(); |
76 | BaseCountedLoopEndNode* le = l->loopexit_or_null(); |
77 | if (le != NULL__null && |
78 | le->proj_out_or_null(1 /* true */) == l->in(LoopNode::LoopBackControl)) { |
79 | Node* phi = l->phi(); |
80 | Node* exit = le->proj_out_or_null(0 /* false */); |
81 | if (exit != NULL__null && exit->Opcode() == Op_IfFalse && |
82 | phi != NULL__null && phi->is_Phi() && |
83 | phi->in(LoopNode::LoopBackControl) == l->incr() && |
84 | le->loopnode() == l && le->stride_is_con()) { |
85 | return true; |
86 | } |
87 | } |
88 | } |
89 | return false; |
90 | } |
91 | |
92 | //------------------------------get_early_ctrl--------------------------------- |
93 | // Compute earliest legal control |
94 | Node *PhaseIdealLoop::get_early_ctrl( Node *n ) { |
95 | assert( !n->is_Phi() && !n->is_CFG(), "this code only handles data nodes" )do { if (!(!n->is_Phi() && !n->is_CFG())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 95, "assert(" "!n->is_Phi() && !n->is_CFG()" ") failed" , "this code only handles data nodes"); ::breakpoint(); } } while (0); |
96 | uint i; |
97 | Node *early; |
98 | if (n->in(0) && !n->is_expensive()) { |
99 | early = n->in(0); |
100 | if (!early->is_CFG()) // Might be a non-CFG multi-def |
101 | early = get_ctrl(early); // So treat input as a straight data input |
102 | i = 1; |
103 | } else { |
104 | early = get_ctrl(n->in(1)); |
105 | i = 2; |
106 | } |
107 | uint e_d = dom_depth(early); |
108 | assert( early, "" )do { if (!(early)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 108, "assert(" "early" ") failed", ""); ::breakpoint(); } } while (0); |
109 | for (; i < n->req(); i++) { |
110 | Node *cin = get_ctrl(n->in(i)); |
111 | assert( cin, "" )do { if (!(cin)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 111, "assert(" "cin" ") failed", ""); ::breakpoint(); } } while (0); |
112 | // Keep deepest dominator depth |
113 | uint c_d = dom_depth(cin); |
114 | if (c_d > e_d) { // Deeper guy? |
115 | early = cin; // Keep deepest found so far |
116 | e_d = c_d; |
117 | } else if (c_d == e_d && // Same depth? |
118 | early != cin) { // If not equal, must use slower algorithm |
119 | // If same depth but not equal, one _must_ dominate the other |
120 | // and we want the deeper (i.e., dominated) guy. |
121 | Node *n1 = early; |
122 | Node *n2 = cin; |
123 | while (1) { |
124 | n1 = idom(n1); // Walk up until break cycle |
125 | n2 = idom(n2); |
126 | if (n1 == cin || // Walked early up to cin |
127 | dom_depth(n2) < c_d) |
128 | break; // early is deeper; keep him |
129 | if (n2 == early || // Walked cin up to early |
130 | dom_depth(n1) < c_d) { |
131 | early = cin; // cin is deeper; keep him |
132 | break; |
133 | } |
134 | } |
135 | e_d = dom_depth(early); // Reset depth register cache |
136 | } |
137 | } |
138 | |
139 | // Return earliest legal location |
140 | assert(early == find_non_split_ctrl(early), "unexpected early control")do { if (!(early == find_non_split_ctrl(early))) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 140, "assert(" "early == find_non_split_ctrl(early)" ") failed" , "unexpected early control"); ::breakpoint(); } } while (0); |
141 | |
142 | if (n->is_expensive() && !_verify_only && !_verify_me) { |
143 | assert(n->in(0), "should have control input")do { if (!(n->in(0))) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 143, "assert(" "n->in(0)" ") failed", "should have control input" ); ::breakpoint(); } } while (0); |
144 | early = get_early_ctrl_for_expensive(n, early); |
145 | } |
146 | |
147 | return early; |
148 | } |
149 | |
150 | //------------------------------get_early_ctrl_for_expensive--------------------------------- |
151 | // Move node up the dominator tree as high as legal while still beneficial |
152 | Node *PhaseIdealLoop::get_early_ctrl_for_expensive(Node *n, Node* earliest) { |
153 | assert(n->in(0) && n->is_expensive(), "expensive node with control input here")do { if (!(n->in(0) && n->is_expensive())) { (* g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 153, "assert(" "n->in(0) && n->is_expensive()" ") failed", "expensive node with control input here"); ::breakpoint (); } } while (0); |
154 | assert(OptimizeExpensiveOps, "optimization off?")do { if (!(OptimizeExpensiveOps)) { (*g_assert_poison) = 'X'; ; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 154, "assert(" "OptimizeExpensiveOps" ") failed", "optimization off?" ); ::breakpoint(); } } while (0); |
155 | |
156 | Node* ctl = n->in(0); |
157 | assert(ctl->is_CFG(), "expensive input 0 must be cfg")do { if (!(ctl->is_CFG())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 157, "assert(" "ctl->is_CFG()" ") failed", "expensive input 0 must be cfg" ); ::breakpoint(); } } while (0); |
158 | uint min_dom_depth = dom_depth(earliest); |
159 | #ifdef ASSERT1 |
160 | if (!is_dominator(ctl, earliest) && !is_dominator(earliest, ctl)) { |
161 | dump_bad_graph("Bad graph detected in get_early_ctrl_for_expensive", n, earliest, ctl); |
162 | assert(false, "Bad graph detected in get_early_ctrl_for_expensive")do { if (!(false)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 162, "assert(" "false" ") failed", "Bad graph detected in get_early_ctrl_for_expensive" ); ::breakpoint(); } } while (0); |
163 | } |
164 | #endif |
165 | if (dom_depth(ctl) < min_dom_depth) { |
166 | return earliest; |
167 | } |
168 | |
169 | while (1) { |
170 | Node *next = ctl; |
171 | // Moving the node out of a loop on the projection of a If |
172 | // confuses loop predication. So once we hit a Loop in a If branch |
173 | // that doesn't branch to an UNC, we stop. The code that process |
174 | // expensive nodes will notice the loop and skip over it to try to |
175 | // move the node further up. |
176 | if (ctl->is_CountedLoop() && ctl->in(1) != NULL__null && ctl->in(1)->in(0) != NULL__null && ctl->in(1)->in(0)->is_If()) { |
177 | if (!ctl->in(1)->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none)) { |
178 | break; |
179 | } |
180 | next = idom(ctl->in(1)->in(0)); |
181 | } else if (ctl->is_Proj()) { |
182 | // We only move it up along a projection if the projection is |
183 | // the single control projection for its parent: same code path, |
184 | // if it's a If with UNC or fallthrough of a call. |
185 | Node* parent_ctl = ctl->in(0); |
186 | if (parent_ctl == NULL__null) { |
187 | break; |
188 | } else if (parent_ctl->is_CountedLoopEnd() && parent_ctl->as_CountedLoopEnd()->loopnode() != NULL__null) { |
189 | next = parent_ctl->as_CountedLoopEnd()->loopnode()->init_control(); |
190 | } else if (parent_ctl->is_If()) { |
191 | if (!ctl->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none)) { |
192 | break; |
193 | } |
194 | assert(idom(ctl) == parent_ctl, "strange")do { if (!(idom(ctl) == parent_ctl)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 194, "assert(" "idom(ctl) == parent_ctl" ") failed", "strange" ); ::breakpoint(); } } while (0); |
195 | next = idom(parent_ctl); |
196 | } else if (ctl->is_CatchProj()) { |
197 | if (ctl->as_Proj()->_con != CatchProjNode::fall_through_index) { |
198 | break; |
199 | } |
200 | assert(parent_ctl->in(0)->in(0)->is_Call(), "strange graph")do { if (!(parent_ctl->in(0)->in(0)->is_Call())) { ( *g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 200, "assert(" "parent_ctl->in(0)->in(0)->is_Call()" ") failed", "strange graph"); ::breakpoint(); } } while (0); |
201 | next = parent_ctl->in(0)->in(0)->in(0); |
202 | } else { |
203 | // Check if parent control has a single projection (this |
204 | // control is the only possible successor of the parent |
205 | // control). If so, we can try to move the node above the |
206 | // parent control. |
207 | int nb_ctl_proj = 0; |
208 | for (DUIterator_Fast imax, i = parent_ctl->fast_outs(imax); i < imax; i++) { |
209 | Node *p = parent_ctl->fast_out(i); |
210 | if (p->is_Proj() && p->is_CFG()) { |
211 | nb_ctl_proj++; |
212 | if (nb_ctl_proj > 1) { |
213 | break; |
214 | } |
215 | } |
216 | } |
217 | |
218 | if (nb_ctl_proj > 1) { |
219 | break; |
220 | } |
221 | assert(parent_ctl->is_Start() || parent_ctl->is_MemBar() || parent_ctl->is_Call() ||do { if (!(parent_ctl->is_Start() || parent_ctl->is_MemBar () || parent_ctl->is_Call() || BarrierSet::barrier_set()-> barrier_set_c2()->is_gc_barrier_node(parent_ctl))) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 222, "assert(" "parent_ctl->is_Start() || parent_ctl->is_MemBar() || parent_ctl->is_Call() || BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(parent_ctl)" ") failed", "unexpected node"); ::breakpoint(); } } while (0 ) |
222 | BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(parent_ctl), "unexpected node")do { if (!(parent_ctl->is_Start() || parent_ctl->is_MemBar () || parent_ctl->is_Call() || BarrierSet::barrier_set()-> barrier_set_c2()->is_gc_barrier_node(parent_ctl))) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 222, "assert(" "parent_ctl->is_Start() || parent_ctl->is_MemBar() || parent_ctl->is_Call() || BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(parent_ctl)" ") failed", "unexpected node"); ::breakpoint(); } } while (0 ); |
223 | assert(idom(ctl) == parent_ctl, "strange")do { if (!(idom(ctl) == parent_ctl)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 223, "assert(" "idom(ctl) == parent_ctl" ") failed", "strange" ); ::breakpoint(); } } while (0); |
224 | next = idom(parent_ctl); |
225 | } |
226 | } else { |
227 | next = idom(ctl); |
228 | } |
229 | if (next->is_Root() || next->is_Start() || dom_depth(next) < min_dom_depth) { |
230 | break; |
231 | } |
232 | ctl = next; |
233 | } |
234 | |
235 | if (ctl != n->in(0)) { |
236 | _igvn.replace_input_of(n, 0, ctl); |
237 | _igvn.hash_insert(n); |
238 | } |
239 | |
240 | return ctl; |
241 | } |
242 | |
243 | |
244 | //------------------------------set_early_ctrl--------------------------------- |
245 | // Set earliest legal control |
246 | void PhaseIdealLoop::set_early_ctrl(Node* n, bool update_body) { |
247 | Node *early = get_early_ctrl(n); |
248 | |
249 | // Record earliest legal location |
250 | set_ctrl(n, early); |
251 | IdealLoopTree *loop = get_loop(early); |
252 | if (update_body && loop->_child == NULL__null) { |
253 | loop->_body.push(n); |
254 | } |
255 | } |
256 | |
257 | //------------------------------set_subtree_ctrl------------------------------- |
258 | // set missing _ctrl entries on new nodes |
259 | void PhaseIdealLoop::set_subtree_ctrl(Node* n, bool update_body) { |
260 | // Already set? Get out. |
261 | if (_nodes[n->_idx]) return; |
262 | // Recursively set _nodes array to indicate where the Node goes |
263 | uint i; |
264 | for (i = 0; i < n->req(); ++i) { |
265 | Node *m = n->in(i); |
266 | if (m && m != C->root()) { |
267 | set_subtree_ctrl(m, update_body); |
268 | } |
269 | } |
270 | |
271 | // Fixup self |
272 | set_early_ctrl(n, update_body); |
273 | } |
274 | |
275 | IdealLoopTree* PhaseIdealLoop::insert_outer_loop(IdealLoopTree* loop, LoopNode* outer_l, Node* outer_ift) { |
276 | IdealLoopTree* outer_ilt = new IdealLoopTree(this, outer_l, outer_ift); |
277 | IdealLoopTree* parent = loop->_parent; |
278 | IdealLoopTree* sibling = parent->_child; |
279 | if (sibling == loop) { |
280 | parent->_child = outer_ilt; |
281 | } else { |
282 | while (sibling->_next != loop) { |
283 | sibling = sibling->_next; |
284 | } |
285 | sibling->_next = outer_ilt; |
286 | } |
287 | outer_ilt->_next = loop->_next; |
288 | outer_ilt->_parent = parent; |
289 | outer_ilt->_child = loop; |
290 | outer_ilt->_nest = loop->_nest; |
291 | loop->_parent = outer_ilt; |
292 | loop->_next = NULL__null; |
293 | loop->_nest++; |
294 | assert(loop->_nest <= SHRT_MAX, "sanity")do { if (!(loop->_nest <= 32767)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 294, "assert(" "loop->_nest <= 32767" ") failed", "sanity" ); ::breakpoint(); } } while (0); |
295 | return outer_ilt; |
296 | } |
297 | |
298 | // Create a skeleton strip mined outer loop: a Loop head before the |
299 | // inner strip mined loop, a safepoint and an exit condition guarded |
300 | // by an opaque node after the inner strip mined loop with a backedge |
301 | // to the loop head. The inner strip mined loop is left as it is. Only |
302 | // once loop optimizations are over, do we adjust the inner loop exit |
303 | // condition to limit its number of iterations, set the outer loop |
304 | // exit condition and add Phis to the outer loop head. Some loop |
305 | // optimizations that operate on the inner strip mined loop need to be |
306 | // aware of the outer strip mined loop: loop unswitching needs to |
307 | // clone the outer loop as well as the inner, unrolling needs to only |
308 | // clone the inner loop etc. No optimizations need to change the outer |
309 | // strip mined loop as it is only a skeleton. |
310 | IdealLoopTree* PhaseIdealLoop::create_outer_strip_mined_loop(BoolNode *test, Node *cmp, Node *init_control, |
311 | IdealLoopTree* loop, float cl_prob, float le_fcnt, |
312 | Node*& entry_control, Node*& iffalse) { |
313 | Node* outer_test = _igvn.intcon(0); |
314 | set_ctrl(outer_test, C->root()); |
315 | Node *orig = iffalse; |
316 | iffalse = iffalse->clone(); |
317 | _igvn.register_new_node_with_optimizer(iffalse); |
318 | set_idom(iffalse, idom(orig), dom_depth(orig)); |
319 | |
320 | IfNode *outer_le = new OuterStripMinedLoopEndNode(iffalse, outer_test, cl_prob, le_fcnt); |
321 | Node *outer_ift = new IfTrueNode (outer_le); |
322 | Node* outer_iff = orig; |
323 | _igvn.replace_input_of(outer_iff, 0, outer_le); |
324 | |
325 | LoopNode *outer_l = new OuterStripMinedLoopNode(C, init_control, outer_ift); |
326 | entry_control = outer_l; |
327 | |
328 | IdealLoopTree* outer_ilt = insert_outer_loop(loop, outer_l, outer_ift); |
329 | |
330 | set_loop(iffalse, outer_ilt); |
331 | // When this code runs, loop bodies have not yet been populated. |
332 | const bool body_populated = false; |
333 | register_control(outer_le, outer_ilt, iffalse, body_populated); |
334 | register_control(outer_ift, outer_ilt, outer_le, body_populated); |
335 | set_idom(outer_iff, outer_le, dom_depth(outer_le)); |
336 | _igvn.register_new_node_with_optimizer(outer_l); |
337 | set_loop(outer_l, outer_ilt); |
338 | set_idom(outer_l, init_control, dom_depth(init_control)+1); |
339 | |
340 | return outer_ilt; |
341 | } |
342 | |
343 | void PhaseIdealLoop::insert_loop_limit_check(ProjNode* limit_check_proj, Node* cmp_limit, Node* bol) { |
344 | Node* new_predicate_proj = create_new_if_for_predicate(limit_check_proj, NULL__null, |
345 | Deoptimization::Reason_loop_limit_check, |
346 | Op_If); |
347 | Node* iff = new_predicate_proj->in(0); |
348 | assert(iff->Opcode() == Op_If, "bad graph shape")do { if (!(iff->Opcode() == Op_If)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 348, "assert(" "iff->Opcode() == Op_If" ") failed", "bad graph shape" ); ::breakpoint(); } } while (0); |
349 | Node* conv = iff->in(1); |
350 | assert(conv->Opcode() == Op_Conv2B, "bad graph shape")do { if (!(conv->Opcode() == Op_Conv2B)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 350, "assert(" "conv->Opcode() == Op_Conv2B" ") failed", "bad graph shape"); ::breakpoint(); } } while (0); |
351 | Node* opaq = conv->in(1); |
352 | assert(opaq->Opcode() == Op_Opaque1, "bad graph shape")do { if (!(opaq->Opcode() == Op_Opaque1)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 352, "assert(" "opaq->Opcode() == Op_Opaque1" ") failed" , "bad graph shape"); ::breakpoint(); } } while (0); |
353 | cmp_limit = _igvn.register_new_node_with_optimizer(cmp_limit); |
354 | bol = _igvn.register_new_node_with_optimizer(bol); |
355 | set_subtree_ctrl(bol, false); |
356 | _igvn.replace_input_of(iff, 1, bol); |
357 | |
358 | #ifndef PRODUCT |
359 | // report that the loop predication has been actually performed |
360 | // for this loop |
361 | if (TraceLoopLimitCheck) { |
362 | tty->print_cr("Counted Loop Limit Check generated:"); |
363 | debug_only( bol->dump(2); )bol->dump(2); |
364 | } |
365 | #endif |
366 | } |
367 | |
368 | Node* PhaseIdealLoop::loop_exit_control(Node* x, IdealLoopTree* loop) { |
369 | // Counted loop head must be a good RegionNode with only 3 not NULL |
370 | // control input edges: Self, Entry, LoopBack. |
371 | if (x->in(LoopNode::Self) == NULL__null || x->req() != 3 || loop->_irreducible) { |
372 | return NULL__null; |
373 | } |
374 | Node *init_control = x->in(LoopNode::EntryControl); |
375 | Node *back_control = x->in(LoopNode::LoopBackControl); |
376 | if (init_control == NULL__null || back_control == NULL__null) { // Partially dead |
377 | return NULL__null; |
378 | } |
379 | // Must also check for TOP when looking for a dead loop |
380 | if (init_control->is_top() || back_control->is_top()) { |
381 | return NULL__null; |
382 | } |
383 | |
384 | // Allow funny placement of Safepoint |
385 | if (back_control->Opcode() == Op_SafePoint) { |
386 | back_control = back_control->in(TypeFunc::Control); |
387 | } |
388 | |
389 | // Controlling test for loop |
390 | Node *iftrue = back_control; |
391 | uint iftrue_op = iftrue->Opcode(); |
392 | if (iftrue_op != Op_IfTrue && |
393 | iftrue_op != Op_IfFalse) { |
394 | // I have a weird back-control. Probably the loop-exit test is in |
395 | // the middle of the loop and I am looking at some trailing control-flow |
396 | // merge point. To fix this I would have to partially peel the loop. |
397 | return NULL__null; // Obscure back-control |
398 | } |
399 | |
400 | // Get boolean guarding loop-back test |
401 | Node *iff = iftrue->in(0); |
402 | if (get_loop(iff) != loop || !iff->in(1)->is_Bool()) { |
403 | return NULL__null; |
404 | } |
405 | return iftrue; |
406 | } |
407 | |
408 | Node* PhaseIdealLoop::loop_exit_test(Node* back_control, IdealLoopTree* loop, Node*& incr, Node*& limit, BoolTest::mask& bt, float& cl_prob) { |
409 | Node* iftrue = back_control; |
410 | uint iftrue_op = iftrue->Opcode(); |
411 | Node* iff = iftrue->in(0); |
412 | BoolNode* test = iff->in(1)->as_Bool(); |
413 | bt = test->_test._test; |
414 | cl_prob = iff->as_If()->_prob; |
415 | if (iftrue_op == Op_IfFalse) { |
416 | bt = BoolTest(bt).negate(); |
417 | cl_prob = 1.0 - cl_prob; |
418 | } |
419 | // Get backedge compare |
420 | Node* cmp = test->in(1); |
421 | if (!cmp->is_Cmp()) { |
422 | return NULL__null; |
423 | } |
424 | |
425 | // Find the trip-counter increment & limit. Limit must be loop invariant. |
426 | incr = cmp->in(1); |
427 | limit = cmp->in(2); |
428 | |
429 | // --------- |
430 | // need 'loop()' test to tell if limit is loop invariant |
431 | // --------- |
432 | |
433 | if (!is_member(loop, get_ctrl(incr))) { // Swapped trip counter and limit? |
434 | Node* tmp = incr; // Then reverse order into the CmpI |
435 | incr = limit; |
436 | limit = tmp; |
437 | bt = BoolTest(bt).commute(); // And commute the exit test |
438 | } |
439 | if (is_member(loop, get_ctrl(limit))) { // Limit must be loop-invariant |
440 | return NULL__null; |
441 | } |
442 | if (!is_member(loop, get_ctrl(incr))) { // Trip counter must be loop-variant |
443 | return NULL__null; |
444 | } |
445 | return cmp; |
446 | } |
447 | |
448 | Node* PhaseIdealLoop::loop_iv_incr(Node* incr, Node* x, IdealLoopTree* loop, Node*& phi_incr) { |
449 | if (incr->is_Phi()) { |
450 | if (incr->as_Phi()->region() != x || incr->req() != 3) { |
451 | return NULL__null; // Not simple trip counter expression |
452 | } |
453 | phi_incr = incr; |
454 | incr = phi_incr->in(LoopNode::LoopBackControl); // Assume incr is on backedge of Phi |
455 | if (!is_member(loop, get_ctrl(incr))) { // Trip counter must be loop-variant |
456 | return NULL__null; |
457 | } |
458 | } |
459 | return incr; |
460 | } |
461 | |
462 | Node* PhaseIdealLoop::loop_iv_stride(Node* incr, IdealLoopTree* loop, Node*& xphi) { |
463 | assert(incr->Opcode() == Op_AddI || incr->Opcode() == Op_AddL, "caller resp.")do { if (!(incr->Opcode() == Op_AddI || incr->Opcode() == Op_AddL)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 463, "assert(" "incr->Opcode() == Op_AddI || incr->Opcode() == Op_AddL" ") failed", "caller resp."); ::breakpoint(); } } while (0); |
464 | // Get merge point |
465 | xphi = incr->in(1); |
466 | Node *stride = incr->in(2); |
467 | if (!stride->is_Con()) { // Oops, swap these |
468 | if (!xphi->is_Con()) { // Is the other guy a constant? |
469 | return NULL__null; // Nope, unknown stride, bail out |
470 | } |
471 | Node *tmp = xphi; // 'incr' is commutative, so ok to swap |
472 | xphi = stride; |
473 | stride = tmp; |
474 | } |
475 | return stride; |
476 | } |
477 | |
478 | PhiNode* PhaseIdealLoop::loop_iv_phi(Node* xphi, Node* phi_incr, Node* x, IdealLoopTree* loop) { |
479 | if (!xphi->is_Phi()) { |
480 | return NULL__null; // Too much math on the trip counter |
481 | } |
482 | if (phi_incr != NULL__null && phi_incr != xphi) { |
483 | return NULL__null; |
484 | } |
485 | PhiNode *phi = xphi->as_Phi(); |
486 | |
487 | // Phi must be of loop header; backedge must wrap to increment |
488 | if (phi->region() != x) { |
489 | return NULL__null; |
490 | } |
491 | return phi; |
492 | } |
493 | |
494 | static int check_stride_overflow(jlong stride_con, const TypeInteger* limit_t, BasicType bt) { |
495 | if (stride_con > 0) { |
496 | if (limit_t->lo_as_long() > (max_signed_integer(bt) - stride_con)) { |
497 | return -1; |
498 | } |
499 | if (limit_t->hi_as_long() > (max_signed_integer(bt) - stride_con)) { |
500 | return 1; |
501 | } |
502 | } else { |
503 | if (limit_t->hi_as_long() < (min_signed_integer(bt) - stride_con)) { |
504 | return -1; |
505 | } |
506 | if (limit_t->lo_as_long() < (min_signed_integer(bt) - stride_con)) { |
507 | return 1; |
508 | } |
509 | } |
510 | return 0; |
511 | } |
512 | |
513 | static bool condition_stride_ok(BoolTest::mask bt, jlong stride_con) { |
514 | // If the condition is inverted and we will be rolling |
515 | // through MININT to MAXINT, then bail out. |
516 | if (bt == BoolTest::eq || // Bail out, but this loop trips at most twice! |
517 | // Odd stride |
518 | (bt == BoolTest::ne && stride_con != 1 && stride_con != -1) || |
519 | // Count down loop rolls through MAXINT |
520 | ((bt == BoolTest::le || bt == BoolTest::lt) && stride_con < 0) || |
521 | // Count up loop rolls through MININT |
522 | ((bt == BoolTest::ge || bt == BoolTest::gt) && stride_con > 0)) { |
523 | return false; // Bail out |
524 | } |
525 | return true; |
526 | } |
527 | |
528 | Node* PhaseIdealLoop::loop_nest_replace_iv(Node* iv_to_replace, Node* inner_iv, Node* outer_phi, Node* inner_head, |
529 | BasicType bt) { |
530 | Node* iv_as_long; |
531 | if (bt == T_LONG) { |
532 | iv_as_long = new ConvI2LNode(inner_iv, TypeLong::INT); |
533 | register_new_node(iv_as_long, inner_head); |
534 | } else { |
535 | iv_as_long = inner_iv; |
536 | } |
537 | Node* iv_replacement = AddNode::make(outer_phi, iv_as_long, bt); |
538 | register_new_node(iv_replacement, inner_head); |
539 | for (DUIterator_Last imin, i = iv_to_replace->last_outs(imin); i >= imin;) { |
540 | Node* u = iv_to_replace->last_out(i); |
541 | #ifdef ASSERT1 |
542 | if (!is_dominator(inner_head, ctrl_or_self(u))) { |
543 | assert(u->is_Phi(), "should be a Phi")do { if (!(u->is_Phi())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 543, "assert(" "u->is_Phi()" ") failed", "should be a Phi" ); ::breakpoint(); } } while (0); |
544 | for (uint j = 1; j < u->req(); j++) { |
545 | if (u->in(j) == iv_to_replace) { |
546 | assert(is_dominator(inner_head, u->in(0)->in(j)), "iv use above loop?")do { if (!(is_dominator(inner_head, u->in(0)->in(j)))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 546, "assert(" "is_dominator(inner_head, u->in(0)->in(j))" ") failed", "iv use above loop?"); ::breakpoint(); } } while (0); |
547 | } |
548 | } |
549 | } |
550 | #endif |
551 | _igvn.rehash_node_delayed(u); |
552 | int nb = u->replace_edge(iv_to_replace, iv_replacement, &_igvn); |
553 | i -= nb; |
554 | } |
555 | return iv_replacement; |
556 | } |
557 | |
558 | void PhaseIdealLoop::add_empty_predicate(Deoptimization::DeoptReason reason, Node* inner_head, IdealLoopTree* loop, SafePointNode* sfpt) { |
559 | if (!C->too_many_traps(reason)) { |
560 | Node *cont = _igvn.intcon(1); |
561 | Node* opq = new Opaque1Node(C, cont); |
562 | _igvn.register_new_node_with_optimizer(opq); |
563 | Node *bol = new Conv2BNode(opq); |
564 | _igvn.register_new_node_with_optimizer(bol); |
565 | set_subtree_ctrl(bol, false); |
566 | IfNode* iff = new IfNode(inner_head->in(LoopNode::EntryControl), bol, PROB_MAX(1.0f-(1e-6f)), COUNT_UNKNOWN(-1.0f)); |
567 | register_control(iff, loop, inner_head->in(LoopNode::EntryControl)); |
568 | Node* iffalse = new IfFalseNode(iff); |
569 | register_control(iffalse, _ltree_root, iff); |
570 | Node* iftrue = new IfTrueNode(iff); |
571 | register_control(iftrue, loop, iff); |
572 | C->add_predicate_opaq(opq); |
573 | |
574 | int trap_request = Deoptimization::make_trap_request(reason, Deoptimization::Action_maybe_recompile); |
575 | address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point(); |
576 | const TypePtr* no_memory_effects = NULL__null; |
577 | JVMState* jvms = sfpt->jvms(); |
Value stored to 'jvms' during its initialization is never read | |
578 | CallNode* unc = new CallStaticJavaNode(OptoRuntime::uncommon_trap_Type(), call_addr, "uncommon_trap", |
579 | no_memory_effects); |
580 | |
581 | Node* mem = NULL__null; |
582 | Node* i_o = NULL__null; |
583 | if (sfpt->is_Call()) { |
584 | mem = sfpt->proj_out(TypeFunc::Memory); |
585 | i_o = sfpt->proj_out(TypeFunc::I_O); |
586 | } else { |
587 | mem = sfpt->memory(); |
588 | i_o = sfpt->i_o(); |
589 | } |
590 | |
591 | Node *frame = new ParmNode(C->start(), TypeFunc::FramePtr); |
592 | register_new_node(frame, C->start()); |
593 | Node *ret = new ParmNode(C->start(), TypeFunc::ReturnAdr); |
594 | register_new_node(ret, C->start()); |
595 | |
596 | unc->init_req(TypeFunc::Control, iffalse); |
597 | unc->init_req(TypeFunc::I_O, i_o); |
598 | unc->init_req(TypeFunc::Memory, mem); // may gc ptrs |
599 | unc->init_req(TypeFunc::FramePtr, frame); |
600 | unc->init_req(TypeFunc::ReturnAdr, ret); |
601 | unc->init_req(TypeFunc::Parms+0, _igvn.intcon(trap_request)); |
602 | unc->set_cnt(PROB_UNLIKELY_MAG(4)(1e-4f)); |
603 | unc->copy_call_debug_info(&_igvn, sfpt); |
604 | |
605 | for (uint i = TypeFunc::Parms; i < unc->req(); i++) { |
606 | set_subtree_ctrl(unc->in(i), false); |
607 | } |
608 | register_control(unc, _ltree_root, iffalse); |
609 | |
610 | Node* ctrl = new ProjNode(unc, TypeFunc::Control); |
611 | register_control(ctrl, _ltree_root, unc); |
612 | Node* halt = new HaltNode(ctrl, frame, "uncommon trap returned which should never happen" PRODUCT_ONLY(COMMA /*reachable*/false)); |
613 | register_control(halt, _ltree_root, ctrl); |
614 | C->root()->add_req(halt); |
615 | |
616 | _igvn.replace_input_of(inner_head, LoopNode::EntryControl, iftrue); |
617 | set_idom(inner_head, iftrue, dom_depth(inner_head)); |
618 | } |
619 | } |
620 | |
621 | // Find a safepoint node that dominates the back edge. We need a |
622 | // SafePointNode so we can use its jvm state to create empty |
623 | // predicates. |
624 | static bool no_side_effect_since_safepoint(Compile* C, Node* x, Node* mem, MergeMemNode* mm) { |
625 | SafePointNode* safepoint = NULL__null; |
626 | for (DUIterator_Fast imax, i = x->fast_outs(imax); i < imax; i++) { |
627 | Node* u = x->fast_out(i); |
628 | if (u->is_Phi() && u->bottom_type() == Type::MEMORY) { |
629 | Node* m = u->in(LoopNode::LoopBackControl); |
630 | if (u->adr_type() == TypePtr::BOTTOM) { |
631 | if (m->is_MergeMem() && mem->is_MergeMem()) { |
632 | if (m != mem DEBUG_ONLY(|| true)|| true) { |
633 | for (MergeMemStream mms(m->as_MergeMem(), mem->as_MergeMem()); mms.next_non_empty2(); ) { |
634 | if (!mms.is_empty()) { |
635 | if (mms.memory() != mms.memory2()) { |
636 | return false; |
637 | } |
638 | #ifdef ASSERT1 |
639 | if (mms.alias_idx() != Compile::AliasIdxBot) { |
640 | mm->set_memory_at(mms.alias_idx(), mem->as_MergeMem()->base_memory()); |
641 | } |
642 | #endif |
643 | } |
644 | } |
645 | } |
646 | } else if (mem->is_MergeMem()) { |
647 | if (m != mem->as_MergeMem()->base_memory()) { |
648 | return false; |
649 | } |
650 | } else { |
651 | return false; |
652 | } |
653 | } else { |
654 | if (mem->is_MergeMem()) { |
655 | if (m != mem->as_MergeMem()->memory_at(C->get_alias_index(u->adr_type()))) { |
656 | return false; |
657 | } |
658 | #ifdef ASSERT1 |
659 | mm->set_memory_at(C->get_alias_index(u->adr_type()), mem->as_MergeMem()->base_memory()); |
660 | #endif |
661 | } else { |
662 | if (m != mem) { |
663 | return false; |
664 | } |
665 | } |
666 | } |
667 | } |
668 | } |
669 | return true; |
670 | } |
671 | |
672 | SafePointNode* PhaseIdealLoop::find_safepoint(Node* back_control, Node* x, IdealLoopTree* loop) { |
673 | IfNode* exit_test = back_control->in(0)->as_If(); |
674 | SafePointNode* safepoint = NULL__null; |
675 | if (exit_test->in(0)->is_SafePoint() && exit_test->in(0)->outcnt() == 1) { |
676 | safepoint = exit_test->in(0)->as_SafePoint(); |
677 | } else { |
678 | Node* c = back_control; |
679 | while (c != x && c->Opcode() != Op_SafePoint) { |
680 | c = idom(c); |
681 | } |
682 | |
683 | if (c->Opcode() == Op_SafePoint) { |
684 | safepoint = c->as_SafePoint(); |
685 | } |
686 | |
687 | if (safepoint == NULL__null) { |
688 | return NULL__null; |
689 | } |
690 | |
691 | Node* mem = safepoint->in(TypeFunc::Memory); |
692 | |
693 | // We can only use that safepoint if there's not side effect |
694 | // between the backedge and the safepoint. |
695 | |
696 | // mm is used for book keeping |
697 | MergeMemNode* mm = NULL__null; |
698 | #ifdef ASSERT1 |
699 | if (mem->is_MergeMem()) { |
700 | mm = mem->clone()->as_MergeMem(); |
701 | _igvn._worklist.push(mm); |
702 | for (MergeMemStream mms(mem->as_MergeMem()); mms.next_non_empty(); ) { |
703 | if (mms.alias_idx() != Compile::AliasIdxBot && loop != get_loop(ctrl_or_self(mms.memory()))) { |
704 | mm->set_memory_at(mms.alias_idx(), mem->as_MergeMem()->base_memory()); |
705 | } |
706 | } |
707 | } |
708 | #endif |
709 | if (!no_side_effect_since_safepoint(C, x, mem, mm)) { |
710 | safepoint = NULL__null; |
711 | } else { |
712 | assert(mm == NULL|| _igvn.transform(mm) == mem->as_MergeMem()->base_memory(), "all memory state should have been processed")do { if (!(mm == __null|| _igvn.transform(mm) == mem->as_MergeMem ()->base_memory())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 712, "assert(" "mm == __null|| _igvn.transform(mm) == mem->as_MergeMem()->base_memory()" ") failed", "all memory state should have been processed"); :: breakpoint(); } } while (0); |
713 | } |
714 | #ifdef ASSERT1 |
715 | if (mm != NULL__null) { |
716 | _igvn.remove_dead_node(mm); |
717 | } |
718 | #endif |
719 | } |
720 | return safepoint; |
721 | } |
722 | |
723 | // If the loop has the shape of a counted loop but with a long |
724 | // induction variable, transform the loop in a loop nest: an inner |
725 | // loop that iterates for at most max int iterations with an integer |
726 | // induction variable and an outer loop that iterates over the full |
727 | // range of long values from the initial loop in (at most) max int |
728 | // steps. That is: |
729 | // |
730 | // x: for (long phi = init; phi < limit; phi += stride) { |
731 | // // phi := Phi(L, init, incr) |
732 | // // incr := AddL(phi, longcon(stride)) |
733 | // long incr = phi + stride; |
734 | // ... use phi and incr ... |
735 | // } |
736 | // |
737 | // OR: |
738 | // |
739 | // x: for (long phi = init; (phi += stride) < limit; ) { |
740 | // // phi := Phi(L, AddL(init, stride), incr) |
741 | // // incr := AddL(phi, longcon(stride)) |
742 | // long incr = phi + stride; |
743 | // ... use phi and (phi + stride) ... |
744 | // } |
745 | // |
746 | // ==transform=> |
747 | // |
748 | // const ulong inner_iters_limit = INT_MAX - stride - 1; //near 0x7FFFFFF0 |
749 | // assert(stride <= inner_iters_limit); // else abort transform |
750 | // assert((extralong)limit + stride <= LONG_MAX); // else deopt |
751 | // outer_head: for (long outer_phi = init;;) { |
752 | // // outer_phi := Phi(outer_head, init, AddL(outer_phi, I2L(inner_phi))) |
753 | // ulong inner_iters_max = (ulong) MAX(0, ((extralong)limit + stride - outer_phi)); |
754 | // long inner_iters_actual = MIN(inner_iters_limit, inner_iters_max); |
755 | // assert(inner_iters_actual == (int)inner_iters_actual); |
756 | // int inner_phi, inner_incr; |
757 | // x: for (inner_phi = 0;; inner_phi = inner_incr) { |
758 | // // inner_phi := Phi(x, intcon(0), inner_incr) |
759 | // // inner_incr := AddI(inner_phi, intcon(stride)) |
760 | // inner_incr = inner_phi + stride; |
761 | // if (inner_incr < inner_iters_actual) { |
762 | // ... use phi=>(outer_phi+inner_phi) and incr=>(outer_phi+inner_incr) ... |
763 | // continue; |
764 | // } |
765 | // else break; |
766 | // } |
767 | // if ((outer_phi+inner_phi) < limit) //OR (outer_phi+inner_incr) < limit |
768 | // continue; |
769 | // else break; |
770 | // } |
771 | // |
772 | // The same logic is used to transform an int counted loop that contains long range checks into a loop nest of 2 int |
773 | // loops with long range checks transformed to int range checks in the inner loop. |
774 | bool PhaseIdealLoop::create_loop_nest(IdealLoopTree* loop, Node_List &old_new) { |
775 | Node* x = loop->_head; |
776 | // Only for inner loops |
777 | if (loop->_child != NULL__null || !x->is_BaseCountedLoop() || x->as_Loop()->is_loop_nest_outer_loop()) { |
778 | return false; |
779 | } |
780 | |
781 | if (x->is_CountedLoop() && !x->as_CountedLoop()->is_main_loop() && !x->as_CountedLoop()->is_normal_loop()) { |
782 | return false; |
783 | } |
784 | |
785 | BaseCountedLoopNode* head = x->as_BaseCountedLoop(); |
786 | BasicType bt = x->as_BaseCountedLoop()->bt(); |
787 | |
788 | check_counted_loop_shape(loop, x, bt); |
789 | |
790 | #ifndef PRODUCT |
791 | if (bt == T_LONG) { |
792 | Atomic::inc(&_long_loop_candidates); |
793 | } |
794 | #endif |
795 | |
796 | jlong stride_con = head->stride_con(); |
797 | assert(stride_con != 0, "missed some peephole opt")do { if (!(stride_con != 0)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 797, "assert(" "stride_con != 0" ") failed", "missed some peephole opt" ); ::breakpoint(); } } while (0); |
798 | // We can't iterate for more than max int at a time. |
799 | if (stride_con != (jint)stride_con) { |
800 | assert(bt == T_LONG, "only for long loops")do { if (!(bt == T_LONG)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 800, "assert(" "bt == T_LONG" ") failed", "only for long loops" ); ::breakpoint(); } } while (0); |
801 | return false; |
802 | } |
803 | // The number of iterations for the integer count loop: guarantee no |
804 | // overflow: max_jint - stride_con max. -1 so there's no need for a |
805 | // loop limit check if the exit test is <= or >=. |
806 | int iters_limit = max_jint - ABS(stride_con) - 1; |
807 | #ifdef ASSERT1 |
808 | if (bt == T_LONG && StressLongCountedLoop > 0) { |
809 | iters_limit = iters_limit / StressLongCountedLoop; |
810 | } |
811 | #endif |
812 | // At least 2 iterations so counted loop construction doesn't fail |
813 | if (iters_limit/ABS(stride_con) < 2) { |
814 | return false; |
815 | } |
816 | |
817 | PhiNode* phi = head->phi()->as_Phi(); |
818 | Node* incr = head->incr(); |
819 | |
820 | Node* back_control = head->in(LoopNode::LoopBackControl); |
821 | |
822 | // data nodes on back branch not supported |
823 | if (back_control->outcnt() > 1) { |
824 | return false; |
825 | } |
826 | |
827 | Node* limit = head->limit(); |
828 | // We'll need to use the loop limit before the inner loop is entered |
829 | if (!is_dominator(get_ctrl(limit), x)) { |
830 | return false; |
831 | } |
832 | |
833 | // May not have gone thru igvn yet so don't use _igvn.type(phi) (PhaseIdealLoop::is_counted_loop() sets the iv phi's type) |
834 | const TypeInteger* phi_t = phi->bottom_type()->is_integer(bt); |
835 | assert(phi_t->hi_as_long() >= phi_t->lo_as_long(), "dead phi?")do { if (!(phi_t->hi_as_long() >= phi_t->lo_as_long( ))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 835, "assert(" "phi_t->hi_as_long() >= phi_t->lo_as_long()" ") failed", "dead phi?"); ::breakpoint(); } } while (0); |
836 | iters_limit = checked_cast<int>(MIN2((julong)iters_limit, (julong)(phi_t->hi_as_long() - phi_t->lo_as_long()))); |
837 | |
838 | IfNode* exit_test = head->loopexit(); |
839 | BoolTest::mask mask = exit_test->as_BaseCountedLoopEnd()->test_trip(); |
840 | Node* cmp = exit_test->as_BaseCountedLoopEnd()->cmp_node(); |
841 | |
842 | assert(back_control->Opcode() == Op_IfTrue, "wrong projection for back edge")do { if (!(back_control->Opcode() == Op_IfTrue)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 842, "assert(" "back_control->Opcode() == Op_IfTrue" ") failed" , "wrong projection for back edge"); ::breakpoint(); } } while (0); |
843 | |
844 | Node_List range_checks; |
845 | iters_limit = extract_long_range_checks(loop, stride_con, iters_limit, phi, range_checks); |
846 | |
847 | if (bt == T_INT) { |
848 | // The only purpose of creating a loop nest is to handle long range checks. If there are none, do not proceed further. |
849 | if (range_checks.size() == 0) { |
850 | return false; |
851 | } |
852 | } |
853 | |
854 | // We need a safepoint to insert empty predicates for the inner loop. |
855 | SafePointNode* safepoint; |
856 | if (bt == T_INT && head->as_CountedLoop()->is_strip_mined()) { |
857 | // Loop is strip mined: use the safepoint of the outer strip mined loop |
858 | strip_mined_nest_back_to_counted_loop(loop, head, back_control, exit_test, safepoint); |
859 | } else { |
860 | safepoint = find_safepoint(back_control, x, loop); |
861 | } |
862 | |
863 | Node* exit_branch = exit_test->proj_out(false); |
864 | Node* entry_control = head->in(LoopNode::EntryControl); |
865 | |
866 | // Clone the control flow of the loop to build an outer loop |
867 | Node* outer_back_branch = back_control->clone(); |
868 | Node* outer_exit_test = new IfNode(exit_test->in(0), exit_test->in(1), exit_test->_prob, exit_test->_fcnt); |
869 | Node* inner_exit_branch = exit_branch->clone(); |
870 | |
871 | LoopNode* outer_head = new LoopNode(entry_control, outer_back_branch); |
872 | IdealLoopTree* outer_ilt = insert_outer_loop(loop, outer_head, outer_back_branch); |
873 | |
874 | const bool body_populated = true; |
875 | register_control(outer_head, outer_ilt, entry_control, body_populated); |
876 | |
877 | _igvn.register_new_node_with_optimizer(inner_exit_branch); |
878 | set_loop(inner_exit_branch, outer_ilt); |
879 | set_idom(inner_exit_branch, exit_test, dom_depth(exit_branch)); |
880 | |
881 | outer_exit_test->set_req(0, inner_exit_branch); |
882 | register_control(outer_exit_test, outer_ilt, inner_exit_branch, body_populated); |
883 | |
884 | _igvn.replace_input_of(exit_branch, 0, outer_exit_test); |
885 | set_idom(exit_branch, outer_exit_test, dom_depth(exit_branch)); |
886 | |
887 | outer_back_branch->set_req(0, outer_exit_test); |
888 | register_control(outer_back_branch, outer_ilt, outer_exit_test, body_populated); |
889 | |
890 | _igvn.replace_input_of(x, LoopNode::EntryControl, outer_head); |
891 | set_idom(x, outer_head, dom_depth(x)); |
892 | |
893 | // add an iv phi to the outer loop and use it to compute the inner |
894 | // loop iteration limit |
895 | Node* outer_phi = phi->clone(); |
896 | outer_phi->set_req(0, outer_head); |
897 | register_new_node(outer_phi, outer_head); |
898 | |
899 | Node* inner_iters_max = NULL__null; |
900 | if (stride_con > 0) { |
901 | inner_iters_max = MaxNode::max_diff_with_zero(limit, outer_phi, TypeInteger::bottom(bt), _igvn); |
902 | } else { |
903 | inner_iters_max = MaxNode::max_diff_with_zero(outer_phi, limit, TypeInteger::bottom(bt), _igvn); |
904 | } |
905 | |
906 | Node* inner_iters_limit = _igvn.integercon(iters_limit, bt); |
907 | // inner_iters_max may not fit in a signed integer (iterating from |
908 | // Long.MIN_VALUE to Long.MAX_VALUE for instance). Use an unsigned |
909 | // min. |
910 | Node* inner_iters_actual = MaxNode::unsigned_min(inner_iters_max, inner_iters_limit, TypeInteger::make(0, iters_limit, Type::WidenMin, bt), _igvn); |
911 | |
912 | Node* inner_iters_actual_int; |
913 | if (bt == T_LONG) { |
914 | inner_iters_actual_int = new ConvL2INode(inner_iters_actual); |
915 | _igvn.register_new_node_with_optimizer(inner_iters_actual_int); |
916 | } else { |
917 | inner_iters_actual_int = inner_iters_actual; |
918 | } |
919 | |
920 | Node* int_zero = _igvn.intcon(0); |
921 | set_ctrl(int_zero, C->root()); |
922 | if (stride_con < 0) { |
923 | inner_iters_actual_int = new SubINode(int_zero, inner_iters_actual_int); |
924 | _igvn.register_new_node_with_optimizer(inner_iters_actual_int); |
925 | } |
926 | |
927 | // Clone the iv data nodes as an integer iv |
928 | Node* int_stride = _igvn.intcon(checked_cast<int>(stride_con)); |
929 | set_ctrl(int_stride, C->root()); |
930 | Node* inner_phi = new PhiNode(x->in(0), TypeInt::INT); |
931 | Node* inner_incr = new AddINode(inner_phi, int_stride); |
932 | Node* inner_cmp = NULL__null; |
933 | inner_cmp = new CmpINode(inner_incr, inner_iters_actual_int); |
934 | Node* inner_bol = new BoolNode(inner_cmp, exit_test->in(1)->as_Bool()->_test._test); |
935 | inner_phi->set_req(LoopNode::EntryControl, int_zero); |
936 | inner_phi->set_req(LoopNode::LoopBackControl, inner_incr); |
937 | register_new_node(inner_phi, x); |
938 | register_new_node(inner_incr, x); |
939 | register_new_node(inner_cmp, x); |
940 | register_new_node(inner_bol, x); |
941 | |
942 | _igvn.replace_input_of(exit_test, 1, inner_bol); |
943 | |
944 | // Clone inner loop phis to outer loop |
945 | for (uint i = 0; i < head->outcnt(); i++) { |
946 | Node* u = head->raw_out(i); |
947 | if (u->is_Phi() && u != inner_phi && u != phi) { |
948 | assert(u->in(0) == head, "inconsistent")do { if (!(u->in(0) == head)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 948, "assert(" "u->in(0) == head" ") failed", "inconsistent" ); ::breakpoint(); } } while (0); |
949 | Node* clone = u->clone(); |
950 | clone->set_req(0, outer_head); |
951 | register_new_node(clone, outer_head); |
952 | _igvn.replace_input_of(u, LoopNode::EntryControl, clone); |
953 | } |
954 | } |
955 | |
956 | // Replace inner loop long iv phi as inner loop int iv phi + outer |
957 | // loop iv phi |
958 | Node* iv_add = loop_nest_replace_iv(phi, inner_phi, outer_phi, head, bt); |
959 | |
960 | // Replace inner loop long iv incr with inner loop int incr + outer |
961 | // loop iv phi |
962 | loop_nest_replace_iv(incr, inner_incr, outer_phi, head, bt); |
963 | |
964 | set_subtree_ctrl(inner_iters_actual_int, body_populated); |
965 | |
966 | LoopNode* inner_head = create_inner_head(loop, head, exit_test); |
967 | |
968 | // Summary of steps from inital loop to loop nest: |
969 | // |
970 | // == old IR nodes => |
971 | // |
972 | // entry_control: {...} |
973 | // x: |
974 | // for (long phi = init;;) { |
975 | // // phi := Phi(x, init, incr) |
976 | // // incr := AddL(phi, longcon(stride)) |
977 | // exit_test: |
978 | // if (phi < limit) |
979 | // back_control: fallthrough; |
980 | // else |
981 | // exit_branch: break; |
982 | // long incr = phi + stride; |
983 | // ... use phi and incr ... |
984 | // phi = incr; |
985 | // } |
986 | // |
987 | // == new IR nodes (just before final peel) => |
988 | // |
989 | // entry_control: {...} |
990 | // long adjusted_limit = limit + stride; //because phi_incr != NULL |
991 | // assert(!limit_check_required || (extralong)limit + stride == adjusted_limit); // else deopt |
992 | // ulong inner_iters_limit = max_jint - ABS(stride) - 1; //near 0x7FFFFFF0 |
993 | // outer_head: |
994 | // for (long outer_phi = init;;) { |
995 | // // outer_phi := phi->clone(), in(0):=outer_head, => Phi(outer_head, init, incr) |
996 | // // REPLACE phi => AddL(outer_phi, I2L(inner_phi)) |
997 | // // REPLACE incr => AddL(outer_phi, I2L(inner_incr)) |
998 | // // SO THAT outer_phi := Phi(outer_head, init, AddL(outer_phi, I2L(inner_incr))) |
999 | // ulong inner_iters_max = (ulong) MAX(0, ((extralong)adjusted_limit - outer_phi) * SGN(stride)); |
1000 | // int inner_iters_actual_int = (int) MIN(inner_iters_limit, inner_iters_max) * SGN(stride); |
1001 | // inner_head: x: //in(1) := outer_head |
1002 | // int inner_phi; |
1003 | // for (inner_phi = 0;;) { |
1004 | // // inner_phi := Phi(x, intcon(0), inner_phi + stride) |
1005 | // int inner_incr = inner_phi + stride; |
1006 | // bool inner_bol = (inner_incr < inner_iters_actual_int); |
1007 | // exit_test: //exit_test->in(1) := inner_bol; |
1008 | // if (inner_bol) // WAS (phi < limit) |
1009 | // back_control: fallthrough; |
1010 | // else |
1011 | // inner_exit_branch: break; //exit_branch->clone() |
1012 | // ... use phi=>(outer_phi+inner_phi) and incr=>(outer_phi+inner_incr) ... |
1013 | // inner_phi = inner_phi + stride; // inner_incr |
1014 | // } |
1015 | // outer_exit_test: //exit_test->clone(), in(0):=inner_exit_branch |
1016 | // if ((outer_phi+inner_phi) < limit) // WAS (phi < limit) |
1017 | // outer_back_branch: fallthrough; //back_control->clone(), in(0):=outer_exit_test |
1018 | // else |
1019 | // exit_branch: break; //in(0) := outer_exit_test |
1020 | // } |
1021 | |
1022 | if (bt == T_INT) { |
1023 | outer_phi = new ConvI2LNode(outer_phi); |
1024 | register_new_node(outer_phi, outer_head); |
1025 | } |
1026 | |
1027 | transform_long_range_checks(checked_cast<int>(stride_con), range_checks, outer_phi, inner_iters_actual_int, |
1028 | inner_phi, iv_add, inner_head); |
1029 | // Peel one iteration of the loop and use the safepoint at the end |
1030 | // of the peeled iteration to insert empty predicates. If no well |
1031 | // positioned safepoint peel to guarantee a safepoint in the outer |
1032 | // loop. |
1033 | if (safepoint != NULL__null || !loop->_has_call) { |
1034 | old_new.clear(); |
1035 | do_peeling(loop, old_new); |
1036 | } else { |
1037 | C->set_major_progress(); |
1038 | } |
1039 | |
1040 | if (safepoint != NULL__null) { |
1041 | SafePointNode* cloned_sfpt = old_new[safepoint->_idx]->as_SafePoint(); |
1042 | |
1043 | if (UseLoopPredicate) { |
1044 | add_empty_predicate(Deoptimization::Reason_predicate, inner_head, outer_ilt, cloned_sfpt); |
1045 | } |
1046 | if (UseProfiledLoopPredicate) { |
1047 | add_empty_predicate(Deoptimization::Reason_profile_predicate, inner_head, outer_ilt, cloned_sfpt); |
1048 | } |
1049 | add_empty_predicate(Deoptimization::Reason_loop_limit_check, inner_head, outer_ilt, cloned_sfpt); |
1050 | } |
1051 | |
1052 | #ifndef PRODUCT |
1053 | if (bt == T_LONG) { |
1054 | Atomic::inc(&_long_loop_nests); |
1055 | } |
1056 | #endif |
1057 | |
1058 | inner_head->mark_loop_nest_inner_loop(); |
1059 | outer_head->mark_loop_nest_outer_loop(); |
1060 | |
1061 | return true; |
1062 | } |
1063 | |
1064 | // Convert the strip mined loop nest back to a single loop with the safepoint right before the loop exit test |
1065 | void PhaseIdealLoop::strip_mined_nest_back_to_counted_loop(IdealLoopTree* loop, const BaseCountedLoopNode* head, |
1066 | Node* back_control, IfNode*& exit_test, |
1067 | SafePointNode*& safepoint) { |
1068 | CountedLoopNode* cl = head->as_CountedLoop(); |
1069 | cl->verify_strip_mined(1); |
1070 | safepoint = cl->outer_safepoint(); |
1071 | CountedLoopEndNode* cle = cl->loopexit(); |
1072 | OuterStripMinedLoopNode* outer_head = cl->outer_loop(); |
1073 | OuterStripMinedLoopEndNode* outer_end = cl->outer_loop_end(); |
1074 | |
1075 | cl->clear_strip_mined(); |
1076 | |
1077 | _igvn.replace_input_of(cl, LoopNode::EntryControl, outer_head->in(LoopNode::EntryControl)); |
1078 | _igvn.replace_input_of(outer_head, LoopNode::EntryControl, C->top()); |
1079 | set_idom(cl, cl->in(LoopNode::EntryControl), dom_depth(cl)); |
1080 | |
1081 | Node* exit_bol = cle->in(1); |
1082 | Node *zero = _igvn.intcon(0); |
1083 | set_ctrl(zero, C->root()); |
1084 | _igvn.replace_input_of(cle, 1, zero); |
1085 | |
1086 | _igvn.replace_input_of(outer_end, 1, exit_bol); |
1087 | |
1088 | assert(outer_head->in(LoopNode::LoopBackControl)->in(0) == outer_end, "")do { if (!(outer_head->in(LoopNode::LoopBackControl)->in (0) == outer_end)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1088, "assert(" "outer_head->in(LoopNode::LoopBackControl)->in(0) == outer_end" ") failed", ""); ::breakpoint(); } } while (0); |
1089 | _igvn.replace_input_of(outer_head->in(LoopNode::LoopBackControl), 0, C->top()); |
1090 | _igvn.replace_input_of(back_control, 0, outer_end); |
1091 | set_idom(back_control, outer_end, dom_depth(outer_end) + 1); |
1092 | |
1093 | Unique_Node_List wq; |
1094 | wq.push(safepoint); |
1095 | |
1096 | IdealLoopTree* outer_loop_ilt = get_loop(outer_head); |
1097 | |
1098 | for (uint i = 0; i < wq.size(); i++) { |
1099 | Node* n = wq.at(i); |
1100 | for (uint j = 0; j < n->req(); ++j) { |
1101 | Node* in = n->in(j); |
1102 | if (in == NULL__null || in->is_CFG()) { |
1103 | continue; |
1104 | } |
1105 | if (get_loop(get_ctrl(in)) != outer_loop_ilt) { |
1106 | continue; |
1107 | } |
1108 | assert(!loop->_body.contains(in), "")do { if (!(!loop->_body.contains(in))) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1108, "assert(" "!loop->_body.contains(in)" ") failed", "" ); ::breakpoint(); } } while (0); |
1109 | loop->_body.push(in); |
1110 | wq.push(in); |
1111 | } |
1112 | } |
1113 | |
1114 | set_loop(outer_end, loop); |
1115 | loop->_body.push(outer_end); |
1116 | set_loop(safepoint, loop); |
1117 | loop->_body.push(safepoint); |
1118 | set_loop(safepoint->in(0), loop); |
1119 | loop->_body.push(safepoint->in(0)); |
1120 | |
1121 | exit_test = outer_end; |
1122 | |
1123 | outer_loop_ilt->_tail = C->top(); |
1124 | } |
1125 | |
1126 | int PhaseIdealLoop::extract_long_range_checks(const IdealLoopTree* loop, jlong stride_con, int iters_limit, PhiNode* phi, |
1127 | Node_List& range_checks) { |
1128 | if (stride_con < 0) { // only for stride_con > 0 && scale > 0 for now |
1129 | return iters_limit; |
1130 | } |
1131 | const jlong min_iters = 2; |
1132 | jlong reduced_iters_limit = iters_limit; |
1133 | jlong original_iters_limit = iters_limit; |
1134 | for (uint i = 0; i < loop->_body.size(); i++) { |
1135 | Node* c = loop->_body.at(i); |
1136 | if (c->is_IfProj() && c->in(0)->is_RangeCheck()) { |
1137 | CallStaticJavaNode* call = c->as_IfProj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none); |
1138 | if (call != NULL__null) { |
1139 | Node* range = NULL__null; |
1140 | Node* offset = NULL__null; |
1141 | jlong scale = 0; |
1142 | RangeCheckNode* rc = c->in(0)->as_RangeCheck(); |
1143 | if (loop->is_range_check_if(rc, this, T_LONG, phi, range, offset, scale) && |
1144 | loop->is_invariant(range) && loop->is_invariant(offset) && |
1145 | scale > 0 && // only for stride_con > 0 && scale > 0 for now |
1146 | original_iters_limit / ABS(scale * stride_con) >= min_iters) { |
1147 | reduced_iters_limit = MIN2(reduced_iters_limit, original_iters_limit/ABS(scale)); |
1148 | range_checks.push(c); |
1149 | } |
1150 | } |
1151 | } |
1152 | } |
1153 | |
1154 | return checked_cast<int>(reduced_iters_limit); |
1155 | } |
1156 | |
1157 | // One execution of the inner loop covers a sub-range of the entire iteration range of the loop: [A,Z), aka [A=init, |
1158 | // Z=limit). If the loop has at least one trip (which is the case here), the iteration variable i always takes A as its |
1159 | // first value, followed by A+S (S is the stride), next A+2S, etc. The limit is exclusive, so that the final value B of |
1160 | // i is never Z. It will be B=Z-1 if S=1, or B=Z+1 if S=-1. If |S|>1 the formula for the last value requires a floor |
1161 | // operation, specifically B=floor((Z-sgn(S)-A)/S)*S+A. Thus i ranges as i:[A,B] or i:[A,Z) or i:[A,Z-U) for some U<S. |
1162 | |
1163 | // N.B. We handle only the case of positive S currently, so comments about S<0 are not operative at present. Also, |
1164 | // we only support positive index scale value (K > 0) to simplify the logic for clamping 32-bit bounds (L_2, R_2). |
1165 | // For restrictions on S and K, see the guards in extract_long_range_checks. |
1166 | |
1167 | // Within the loop there may be many range checks. Each such range check (R.C.) is of the form 0 <= i*K+L < R, where K |
1168 | // is a scale factor applied to the loop iteration variable i, and L is some offset; K, L, and R are loop-invariant. |
1169 | // Because R is never negative, this check can always be simplified to an unsigned check i*K+L <u R. |
1170 | |
1171 | // When a long loop over a 64-bit variable i (outer_iv) is decomposed into a series of shorter sub-loops over a 32-bit |
1172 | // variable j (inner_iv), j ranges over a shorter interval j:[0,Z_2), where the limit is chosen to prevent various cases |
1173 | // of 32-bit overflow (including multiplications j*K below). In the sub-loop the logical value i is offset from j by a |
1174 | // 64-bit constant C, so i ranges in i:C+[0,Z_2). |
1175 | |
1176 | // The union of all the C+[0,Z_2) ranges from the sub-loops must be identical to the whole range [A,B]. Assuming S>0, |
1177 | // the first C must be A itself, and the next C value is the previous C+Z_2. In each sub-loop, j counts up from zero |
1178 | // and exits just before i=C+Z_2. |
1179 | |
1180 | // (N.B. If S<0 the formulas are different, because all the loops count downward.) |
1181 | |
1182 | // Returning to range checks, we see that each i*K+L <u R expands to (C+j)*K+L <u R, or j*K+Q <u R, where Q=(C*K+L). |
1183 | // (Recall that K and L and R are loop-invariant scale, offset and range values for a particular R.C.) This is still a |
1184 | // 64-bit comparison, so the range check elimination logic will not apply to it. (The R.C.E. transforms operate only on |
1185 | // 32-bit indexes and comparisons, because they use 64-bit temporary values to avoid overflow; see |
1186 | // PhaseIdealLoop::add_constraint.) |
1187 | |
1188 | // We must transform this comparison so that it gets the same answer, but by means of a 32-bit R.C. (using j not i) of |
1189 | // the form j*K+L_2 <u32 R_2. Note that L_2 and R_2 must be loop-invariant, but only with respect to the sub-loop. Thus, the |
1190 | // problem reduces to computing values for L_2 and R_2 (for each R.C. in the loop) in the loop header for the sub-loop. |
1191 | // Then the standard R.C.E. transforms can take those as inputs and further compute the necessary minimum and maximum |
1192 | // values for the 32-bit counter j within which the range checks can be eliminated. |
1193 | |
1194 | // So, given j*K+Q <u R, we need to find some j*K+L_2 <u32 R_2, where L_2 and R_2 fit in 32 bits, and the 32-bit operations do |
1195 | // not overflow. We also need to cover the cases where i*K+L (= j*K+Q) overflows to a 64-bit negative, since that is |
1196 | // allowed as an input to the R.C., as long as the R.C. as a whole fails. |
1197 | |
1198 | // If 32-bit multiplication j*K might overflow, we adjust the sub-loop limit Z_2 closer to zero to reduce j's range. |
1199 | |
1200 | // For each R.C. j*K+Q <u32 R, the range of mathematical values of j*K+Q in the sub-loop is [Q_min, Q_max), where |
1201 | // Q_min=Q and Q_max=Z_2*K+Q. Making the upper limit Q_max be exclusive helps it integrate correctly with the strict |
1202 | // comparisons against R and R_2. Sometimes a very high R will be replaced by an R_2 derived from the more moderate |
1203 | // Q_max, and replacing one exclusive limit by another exclusive limit avoids off-by-one complexities. |
1204 | |
1205 | // N.B. If (S*K)<0 then the formulas for Q_min and Q_max may differ; the values may need to be swapped and adjusted to |
1206 | // the correct type of bound (inclusive or exclusive). |
1207 | |
1208 | // Case A: Some Negatives (but no overflow). |
1209 | // Number line: |
1210 | // |s64_min . . . 0 . . . s64_max| |
1211 | // | . Q_min..Q_max . 0 . . . . | s64 negative |
1212 | // | . . . Q_min..0..Q_max . . . | small mixed |
1213 | // |
1214 | // if Q_min <s64 0, then use this test: |
1215 | // j*K + s32_trunc(Q_min) <u32 clamp(R, 0, Q_max) |
1216 | |
1217 | // If the 32-bit truncation loses information, no harm is done, since certainly the clamp also returns R_2=zero. |
1218 | |
1219 | // Case B: No Negatives. |
1220 | // Number line: |
1221 | // |s64_min . . . 0 . . . s64_max| |
1222 | // | . . . . 0 Q_min..Q_max . . | small positive |
1223 | // | . . . . 0 . Q_min..Q_max . | s64 positive |
1224 | // |
1225 | // if both Q_min, Q_max >=s64 0, then use this test: |
1226 | // j*K + 0 <u32 clamp(R, Q_min, Q_max) - Q_min |
1227 | // or equivalently: |
1228 | // j*K + 0 <u32 clamp(R - Q_min, 0, Q_max - Q_min) |
1229 | |
1230 | // Case C: Overflow in the 64-bit domain |
1231 | // Number line: |
1232 | // |..Q_max-2^64 . . 0 . . . Q_min..| s64 overflow |
1233 | // |
1234 | // if Q_min >=s64 0 but Q_max <s64 0, then use this test: |
1235 | // j*K + 0 <u32 clamp(R, Q_min, R) - Q_min |
1236 | // or equivalently: |
1237 | // j*K + 0 <u32 clamp(R - Q_min, 0, R - Q_min) |
1238 | // or also equivalently: |
1239 | // j*K + 0 <u32 max(0, R - Q_min) |
1240 | // |
1241 | // Here the clamp function is a simple 64-bit min/max: |
1242 | // clamp(X, L, H) := max(L, min(X, H)) |
1243 | // When degenerately L > H, it returns L not H. |
1244 | // |
1245 | // Tests above can be merged into a single one: |
1246 | // L_clamp = Q_min < 0 ? 0 : Q_min |
1247 | // H_clamp = Q_max < Q_min ? R : Q_max |
1248 | // j*K + Q_min - L_clamp <u32 clamp(R, L_clamp, H_clamp) - L_clamp |
1249 | // or equivalently: |
1250 | // j*K + Q_min - L_clamp <u32 clamp(R - L_clamp, 0, H_clamp - L_clamp) |
1251 | // |
1252 | // Readers may find the equivalent forms easier to reason about, but the forms given first generate better code. |
1253 | |
1254 | void PhaseIdealLoop::transform_long_range_checks(int stride_con, const Node_List &range_checks, Node* outer_phi, |
1255 | Node* inner_iters_actual_int, Node* inner_phi, |
1256 | Node* iv_add, LoopNode* inner_head) { |
1257 | Node* long_zero = _igvn.longcon(0); |
1258 | set_ctrl(long_zero, C->root()); |
1259 | |
1260 | for (uint i = 0; i < range_checks.size(); i++) { |
1261 | ProjNode* proj = range_checks.at(i)->as_Proj(); |
1262 | ProjNode* unc_proj = proj->other_if_proj(); |
1263 | RangeCheckNode* rc = proj->in(0)->as_RangeCheck(); |
1264 | jlong scale = 0; |
1265 | Node* offset = NULL__null; |
1266 | Node* rc_bol = rc->in(1); |
1267 | Node* rc_cmp = rc_bol->in(1); |
1268 | if (rc_cmp->Opcode() == Op_CmpU) { |
1269 | // could be shared and have already been taken care of |
1270 | continue; |
1271 | } |
1272 | bool converted = false; |
1273 | bool ok = is_scaled_iv_plus_offset(rc_cmp->in(1), iv_add, &scale, &offset, T_LONG, &converted); |
1274 | assert(ok, "inconsistent: was tested before")do { if (!(ok)) { (*g_assert_poison) = 'X';; report_vm_error( "/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1274, "assert(" "ok" ") failed", "inconsistent: was tested before" ); ::breakpoint(); } } while (0); |
1275 | Node* range = rc_cmp->in(2); |
1276 | Node* c = rc->in(0); |
1277 | Node* entry_control = inner_head->in(LoopNode::EntryControl); |
1278 | |
1279 | Node* R = range; |
1280 | Node* K = _igvn.longcon(scale); |
1281 | set_ctrl(K, this->C->root()); |
1282 | |
1283 | Node* L = offset; |
1284 | |
1285 | if (converted) { |
1286 | // This converts: |
1287 | // i*K + L <u64 R |
1288 | // with K an int into: |
1289 | // i*(long)K + L <u64 unsigned_min((long)max_jint + L + 1, R) |
1290 | // to protect against an overflow of i*K |
1291 | // |
1292 | // Because if i*K overflows, there are K,L where: |
1293 | // i*K + L <u64 R is false |
1294 | // when |
1295 | // i*(long)K is > (long)max_jint and < R |
1296 | // and so i*(long)K + L <u64 R is true |
1297 | // As a consequence simply converting: |
1298 | // i*K + L <u64 R to i*(long)K + L <u64 R could cause incorrect execution |
1299 | // |
1300 | // It's always true that: |
1301 | // i*K <u64 (long)max_jint + 1 |
1302 | // which implies i*K + L <u64 (long)max_jint + 1 + L |
1303 | // As a consequence: |
1304 | // i*(long)K + L <u64 unsigned_min((long)max_jint + L + 1, R) |
1305 | // is always false in case of overflow of i*K |
1306 | // |
1307 | // Note, there are K,L where i*K overflows and |
1308 | // i*K + L <u64 R is true, but |
1309 | // i*(long)K + L <u64 unsigned_min((long)max_jint + L + 1, R) is false |
1310 | // So this transformation could cause spurious deoptimizations and failed range check elimination |
1311 | // (but not incorrect execution) for unlikely corner cases with overflow |
1312 | Node* max_jint_plus_one_long = _igvn.longcon((jlong)max_jint + 1); |
1313 | set_ctrl(max_jint_plus_one_long, C->root()); |
1314 | Node* max_range = new AddLNode(max_jint_plus_one_long, L); |
1315 | register_new_node(max_range, entry_control); |
1316 | R = MaxNode::unsigned_min(R, max_range, TypeLong::POS, _igvn); |
1317 | set_subtree_ctrl(R, true); |
1318 | } |
1319 | |
1320 | Node* C = outer_phi; |
1321 | Node* Z_2 = new ConvI2LNode(inner_iters_actual_int, TypeLong::LONG); |
1322 | register_new_node(Z_2, entry_control); |
1323 | |
1324 | // Start with 64-bit values: |
1325 | // i*K + L <u64 R |
1326 | // (C+j)*K + L <u64 R |
1327 | // j*K + L_2 <u64 R where L_2 = C*K+L |
1328 | Node* L_2 = new MulLNode(C, K); |
1329 | register_new_node(L_2, entry_control); |
1330 | L_2 = new AddLNode(L_2, L); |
1331 | register_new_node(L_2, entry_control); |
1332 | |
1333 | // Compute endpoints of the range of values j*K. |
1334 | // Q_min = (j=0)*K + L_2; Q_max = (j=Z_2)*K + L_2 |
1335 | Node* Q_min = L_2; |
1336 | Node* Q_max = new MulLNode(Z_2, K); |
1337 | register_new_node(Q_max, entry_control); |
1338 | Q_max = new AddLNode(Q_max, L_2); |
1339 | register_new_node(Q_max, entry_control); |
1340 | |
1341 | // L_clamp = Q_min < 0 ? 0 : Q_min |
1342 | Node* Q_min_cmp = new CmpLNode(Q_min, long_zero); |
1343 | register_new_node(Q_min_cmp, entry_control); |
1344 | Node* Q_min_bool = new BoolNode(Q_min_cmp, BoolTest::lt); |
1345 | register_new_node(Q_min_bool, entry_control); |
1346 | Node* L_clamp = new CMoveLNode(Q_min_bool, Q_min, long_zero, TypeLong::LONG); |
1347 | register_new_node(L_clamp, entry_control); |
1348 | |
1349 | // H_clamp = Q_max < Q_min ? R : Q_max |
1350 | Node* Q_max_cmp = new CmpLNode(Q_max, Q_min); |
1351 | register_new_node(Q_max_cmp, entry_control); |
1352 | Node* Q_max_bool = new BoolNode(Q_max_cmp, BoolTest::lt); |
1353 | register_new_node(Q_max_bool, entry_control); |
1354 | Node* H_clamp = new CMoveLNode(Q_max_bool, Q_max, R, TypeLong::LONG); |
1355 | register_new_node(H_clamp, entry_control); |
1356 | |
1357 | // R_2 = clamp(R, L_clamp, H_clamp) - L_clamp |
1358 | // that is: R_2 = clamp(R, L_clamp, H_clamp) if Q_min < 0 |
1359 | // or: R_2 = clamp(R, L_clamp, H_clamp) - Q_min if Q_min > 0 |
1360 | Node* R_2 = clamp(R, L_clamp, H_clamp); |
1361 | R_2 = new SubLNode(R_2, L_clamp); |
1362 | register_new_node(R_2, entry_control); |
1363 | R_2 = new ConvL2INode(R_2, TypeInt::POS); |
1364 | register_new_node(R_2, entry_control); |
1365 | |
1366 | // Q = Q_min - L_clamp |
1367 | // that is: Q = Q_min - 0 if Q_min < 0 |
1368 | // or: Q = Q_min - Q_min = 0 if Q_min > 0 |
1369 | Node* Q = new SubLNode(Q_min, L_clamp); |
1370 | register_new_node(Q, entry_control); |
1371 | Q = new ConvL2INode(Q, TypeInt::INT); |
1372 | register_new_node(Q, entry_control); |
1373 | |
1374 | // Transform the range check |
1375 | K = _igvn.intcon(checked_cast<int>(scale)); |
1376 | set_ctrl(K, this->C->root()); |
1377 | Node* scaled_iv = new MulINode(inner_phi, K); |
1378 | register_new_node(scaled_iv, c); |
1379 | Node* scaled_iv_plus_offset = scaled_iv_plus_offset = new AddINode(scaled_iv, Q); |
1380 | register_new_node(scaled_iv_plus_offset, c); |
1381 | |
1382 | Node* new_rc_cmp = new CmpUNode(scaled_iv_plus_offset, R_2); |
1383 | register_new_node(new_rc_cmp, c); |
1384 | |
1385 | _igvn.replace_input_of(rc_bol, 1, new_rc_cmp); |
1386 | } |
1387 | } |
1388 | |
1389 | Node* PhaseIdealLoop::clamp(Node* R, Node* L, Node* H) { |
1390 | Node* min = MaxNode::signed_min(R, H, TypeLong::LONG, _igvn); |
1391 | set_subtree_ctrl(min, true); |
1392 | Node* max = MaxNode::signed_max(L, min, TypeLong::LONG, _igvn); |
1393 | set_subtree_ctrl(max, true); |
1394 | return max; |
1395 | } |
1396 | |
1397 | LoopNode* PhaseIdealLoop::create_inner_head(IdealLoopTree* loop, BaseCountedLoopNode* head, |
1398 | IfNode* exit_test) { |
1399 | LoopNode* new_inner_head = new LoopNode(head->in(1), head->in(2)); |
1400 | IfNode* new_inner_exit = new IfNode(exit_test->in(0), exit_test->in(1), exit_test->_prob, exit_test->_fcnt); |
1401 | _igvn.register_new_node_with_optimizer(new_inner_head); |
1402 | _igvn.register_new_node_with_optimizer(new_inner_exit); |
1403 | loop->_body.push(new_inner_head); |
1404 | loop->_body.push(new_inner_exit); |
1405 | loop->_body.yank(head); |
1406 | loop->_body.yank(exit_test); |
1407 | set_loop(new_inner_head, loop); |
1408 | set_loop(new_inner_exit, loop); |
1409 | set_idom(new_inner_head, idom(head), dom_depth(head)); |
1410 | set_idom(new_inner_exit, idom(exit_test), dom_depth(exit_test)); |
1411 | lazy_replace(head, new_inner_head); |
1412 | lazy_replace(exit_test, new_inner_exit); |
1413 | loop->_head = new_inner_head; |
1414 | return new_inner_head; |
1415 | } |
1416 | |
1417 | #ifdef ASSERT1 |
1418 | void PhaseIdealLoop::check_counted_loop_shape(IdealLoopTree* loop, Node* x, BasicType bt) { |
1419 | Node* back_control = loop_exit_control(x, loop); |
1420 | assert(back_control != NULL, "no back control")do { if (!(back_control != __null)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1420, "assert(" "back_control != __null" ") failed", "no back control" ); ::breakpoint(); } } while (0); |
1421 | |
1422 | BoolTest::mask mask = BoolTest::illegal; |
1423 | float cl_prob = 0; |
1424 | Node* incr = NULL__null; |
1425 | Node* limit = NULL__null; |
1426 | |
1427 | Node* cmp = loop_exit_test(back_control, loop, incr, limit, mask, cl_prob); |
1428 | assert(cmp != NULL && cmp->Opcode() == Op_Cmp(bt), "no exit test")do { if (!(cmp != __null && cmp->Opcode() == Op_Cmp (bt))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1428, "assert(" "cmp != __null && cmp->Opcode() == Op_Cmp(bt)" ") failed", "no exit test"); ::breakpoint(); } } while (0); |
1429 | |
1430 | Node* phi_incr = NULL__null; |
1431 | incr = loop_iv_incr(incr, x, loop, phi_incr); |
1432 | assert(incr != NULL && incr->Opcode() == Op_Add(bt), "no incr")do { if (!(incr != __null && incr->Opcode() == Op_Add (bt))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1432, "assert(" "incr != __null && incr->Opcode() == Op_Add(bt)" ") failed", "no incr"); ::breakpoint(); } } while (0); |
1433 | |
1434 | Node* xphi = NULL__null; |
1435 | Node* stride = loop_iv_stride(incr, loop, xphi); |
1436 | |
1437 | assert(stride != NULL, "no stride")do { if (!(stride != __null)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1437, "assert(" "stride != __null" ") failed", "no stride") ; ::breakpoint(); } } while (0); |
1438 | |
1439 | PhiNode* phi = loop_iv_phi(xphi, phi_incr, x, loop); |
1440 | |
1441 | assert(phi != NULL && phi->in(LoopNode::LoopBackControl) == incr, "No phi")do { if (!(phi != __null && phi->in(LoopNode::LoopBackControl ) == incr)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1441, "assert(" "phi != __null && phi->in(LoopNode::LoopBackControl) == incr" ") failed", "No phi"); ::breakpoint(); } } while (0); |
1442 | |
1443 | jlong stride_con = stride->get_integer_as_long(bt); |
1444 | |
1445 | assert(condition_stride_ok(mask, stride_con), "illegal condition")do { if (!(condition_stride_ok(mask, stride_con))) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1445, "assert(" "condition_stride_ok(mask, stride_con)" ") failed" , "illegal condition"); ::breakpoint(); } } while (0); |
1446 | |
1447 | assert(mask != BoolTest::ne, "unexpected condition")do { if (!(mask != BoolTest::ne)) { (*g_assert_poison) = 'X'; ; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1447, "assert(" "mask != BoolTest::ne" ") failed", "unexpected condition" ); ::breakpoint(); } } while (0); |
1448 | assert(phi_incr == NULL, "bad loop shape")do { if (!(phi_incr == __null)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1448, "assert(" "phi_incr == __null" ") failed", "bad loop shape" ); ::breakpoint(); } } while (0); |
1449 | assert(cmp->in(1) == incr, "bad exit test shape")do { if (!(cmp->in(1) == incr)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1449, "assert(" "cmp->in(1) == incr" ") failed", "bad exit test shape" ); ::breakpoint(); } } while (0); |
1450 | |
1451 | // Safepoint on backedge not supported |
1452 | assert(x->in(LoopNode::LoopBackControl)->Opcode() != Op_SafePoint, "no safepoint on backedge")do { if (!(x->in(LoopNode::LoopBackControl)->Opcode() != Op_SafePoint)) { (*g_assert_poison) = 'X';; report_vm_error( "/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1452, "assert(" "x->in(LoopNode::LoopBackControl)->Opcode() != Op_SafePoint" ") failed", "no safepoint on backedge"); ::breakpoint(); } } while (0); |
1453 | } |
1454 | #endif |
1455 | |
1456 | #ifdef ASSERT1 |
1457 | // convert an int counted loop to a long counted to stress handling of |
1458 | // long counted loops |
1459 | bool PhaseIdealLoop::convert_to_long_loop(Node* cmp, Node* phi, IdealLoopTree* loop) { |
1460 | Unique_Node_List iv_nodes; |
1461 | Node_List old_new; |
1462 | iv_nodes.push(cmp); |
1463 | bool failed = false; |
1464 | |
1465 | for (uint i = 0; i < iv_nodes.size() && !failed; i++) { |
1466 | Node* n = iv_nodes.at(i); |
1467 | switch(n->Opcode()) { |
1468 | case Op_Phi: { |
1469 | Node* clone = new PhiNode(n->in(0), TypeLong::LONG); |
1470 | old_new.map(n->_idx, clone); |
1471 | break; |
1472 | } |
1473 | case Op_CmpI: { |
1474 | Node* clone = new CmpLNode(NULL__null, NULL__null); |
1475 | old_new.map(n->_idx, clone); |
1476 | break; |
1477 | } |
1478 | case Op_AddI: { |
1479 | Node* clone = new AddLNode(NULL__null, NULL__null); |
1480 | old_new.map(n->_idx, clone); |
1481 | break; |
1482 | } |
1483 | case Op_CastII: { |
1484 | failed = true; |
1485 | break; |
1486 | } |
1487 | default: |
1488 | DEBUG_ONLY(n->dump())n->dump(); |
1489 | fatal("unexpected")do { (*g_assert_poison) = 'X';; report_fatal(INTERNAL_ERROR, "/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1489, "unexpected"); ::breakpoint(); } while (0); |
1490 | } |
1491 | |
1492 | for (uint i = 1; i < n->req(); i++) { |
1493 | Node* in = n->in(i); |
1494 | if (in == NULL__null) { |
1495 | continue; |
1496 | } |
1497 | if (loop->is_member(get_loop(get_ctrl(in)))) { |
1498 | iv_nodes.push(in); |
1499 | } |
1500 | } |
1501 | } |
1502 | |
1503 | if (failed) { |
1504 | for (uint i = 0; i < iv_nodes.size(); i++) { |
1505 | Node* n = iv_nodes.at(i); |
1506 | Node* clone = old_new[n->_idx]; |
1507 | if (clone != NULL__null) { |
1508 | _igvn.remove_dead_node(clone); |
1509 | } |
1510 | } |
1511 | return false; |
1512 | } |
1513 | |
1514 | for (uint i = 0; i < iv_nodes.size(); i++) { |
1515 | Node* n = iv_nodes.at(i); |
1516 | Node* clone = old_new[n->_idx]; |
1517 | for (uint i = 1; i < n->req(); i++) { |
1518 | Node* in = n->in(i); |
1519 | if (in == NULL__null) { |
1520 | continue; |
1521 | } |
1522 | Node* in_clone = old_new[in->_idx]; |
1523 | if (in_clone == NULL__null) { |
1524 | assert(_igvn.type(in)->isa_int(), "")do { if (!(_igvn.type(in)->isa_int())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1524, "assert(" "_igvn.type(in)->isa_int()" ") failed", "" ); ::breakpoint(); } } while (0); |
1525 | in_clone = new ConvI2LNode(in); |
1526 | _igvn.register_new_node_with_optimizer(in_clone); |
1527 | set_subtree_ctrl(in_clone, false); |
1528 | } |
1529 | if (in_clone->in(0) == NULL__null) { |
1530 | in_clone->set_req(0, C->top()); |
1531 | clone->set_req(i, in_clone); |
1532 | in_clone->set_req(0, NULL__null); |
1533 | } else { |
1534 | clone->set_req(i, in_clone); |
1535 | } |
1536 | } |
1537 | _igvn.register_new_node_with_optimizer(clone); |
1538 | } |
1539 | set_ctrl(old_new[phi->_idx], phi->in(0)); |
1540 | |
1541 | for (uint i = 0; i < iv_nodes.size(); i++) { |
1542 | Node* n = iv_nodes.at(i); |
1543 | Node* clone = old_new[n->_idx]; |
1544 | set_subtree_ctrl(clone, false); |
1545 | Node* m = n->Opcode() == Op_CmpI ? clone : NULL__null; |
1546 | for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { |
1547 | Node* u = n->fast_out(i); |
1548 | if (iv_nodes.member(u)) { |
1549 | continue; |
1550 | } |
1551 | if (m == NULL__null) { |
1552 | m = new ConvL2INode(clone); |
1553 | _igvn.register_new_node_with_optimizer(m); |
1554 | set_subtree_ctrl(m, false); |
1555 | } |
1556 | _igvn.rehash_node_delayed(u); |
1557 | int nb = u->replace_edge(n, m, &_igvn); |
1558 | --i, imax -= nb; |
1559 | } |
1560 | } |
1561 | return true; |
1562 | } |
1563 | #endif |
1564 | |
1565 | //------------------------------is_counted_loop-------------------------------- |
1566 | bool PhaseIdealLoop::is_counted_loop(Node* x, IdealLoopTree*&loop, BasicType iv_bt) { |
1567 | PhaseGVN *gvn = &_igvn; |
1568 | |
1569 | Node* back_control = loop_exit_control(x, loop); |
1570 | if (back_control == NULL__null) { |
1571 | return false; |
1572 | } |
1573 | |
1574 | BoolTest::mask bt = BoolTest::illegal; |
1575 | float cl_prob = 0; |
1576 | Node* incr = NULL__null; |
1577 | Node* limit = NULL__null; |
1578 | Node* cmp = loop_exit_test(back_control, loop, incr, limit, bt, cl_prob); |
1579 | if (cmp == NULL__null || cmp->Opcode() != Op_Cmp(iv_bt)) { |
1580 | return false; // Avoid pointer & float & 64-bit compares |
1581 | } |
1582 | |
1583 | // Trip-counter increment must be commutative & associative. |
1584 | if (incr->Opcode() == Op_Cast(iv_bt)) { |
1585 | incr = incr->in(1); |
1586 | } |
1587 | |
1588 | Node* phi_incr = NULL__null; |
1589 | incr = loop_iv_incr(incr, x, loop, phi_incr); |
1590 | if (incr == NULL__null) { |
1591 | return false; |
1592 | } |
1593 | |
1594 | Node* trunc1 = NULL__null; |
1595 | Node* trunc2 = NULL__null; |
1596 | const TypeInteger* iv_trunc_t = NULL__null; |
1597 | Node* orig_incr = incr; |
1598 | if (!(incr = CountedLoopNode::match_incr_with_optional_truncation(incr, &trunc1, &trunc2, &iv_trunc_t, iv_bt))) { |
1599 | return false; // Funny increment opcode |
1600 | } |
1601 | assert(incr->Opcode() == Op_Add(iv_bt), "wrong increment code")do { if (!(incr->Opcode() == Op_Add(iv_bt))) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1601, "assert(" "incr->Opcode() == Op_Add(iv_bt)" ") failed" , "wrong increment code"); ::breakpoint(); } } while (0); |
1602 | |
1603 | Node* xphi = NULL__null; |
1604 | Node* stride = loop_iv_stride(incr, loop, xphi); |
1605 | |
1606 | if (stride == NULL__null) { |
1607 | return false; |
1608 | } |
1609 | |
1610 | if (xphi->Opcode() == Op_Cast(iv_bt)) { |
1611 | xphi = xphi->in(1); |
1612 | } |
1613 | |
1614 | // Stride must be constant |
1615 | jlong stride_con = stride->get_integer_as_long(iv_bt); |
1616 | assert(stride_con != 0, "missed some peephole opt")do { if (!(stride_con != 0)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1616, "assert(" "stride_con != 0" ") failed", "missed some peephole opt" ); ::breakpoint(); } } while (0); |
1617 | |
1618 | PhiNode* phi = loop_iv_phi(xphi, phi_incr, x, loop); |
1619 | |
1620 | if (phi == NULL__null || |
1621 | (trunc1 == NULL__null && phi->in(LoopNode::LoopBackControl) != incr) || |
1622 | (trunc1 != NULL__null && phi->in(LoopNode::LoopBackControl) != trunc1)) { |
1623 | return false; |
1624 | } |
1625 | |
1626 | if (x->in(LoopNode::LoopBackControl)->Opcode() == Op_SafePoint && |
1627 | ((iv_bt == T_INT && LoopStripMiningIter != 0) || |
1628 | iv_bt == T_LONG)) { |
1629 | // Leaving the safepoint on the backedge and creating a |
1630 | // CountedLoop will confuse optimizations. We can't move the |
1631 | // safepoint around because its jvm state wouldn't match a new |
1632 | // location. Give up on that loop. |
1633 | return false; |
1634 | } |
1635 | |
1636 | Node* iftrue = back_control; |
1637 | uint iftrue_op = iftrue->Opcode(); |
1638 | Node* iff = iftrue->in(0); |
1639 | BoolNode* test = iff->in(1)->as_Bool(); |
1640 | |
1641 | const TypeInteger* limit_t = gvn->type(limit)->is_integer(iv_bt); |
1642 | if (trunc1 != NULL__null) { |
1643 | // When there is a truncation, we must be sure that after the truncation |
1644 | // the trip counter will end up higher than the limit, otherwise we are looking |
1645 | // at an endless loop. Can happen with range checks. |
1646 | |
1647 | // Example: |
1648 | // int i = 0; |
1649 | // while (true) |
1650 | // sum + = array[i]; |
1651 | // i++; |
1652 | // i = i && 0x7fff; |
1653 | // } |
1654 | // |
1655 | // If the array is shorter than 0x8000 this exits through a AIOOB |
1656 | // - Counted loop transformation is ok |
1657 | // If the array is longer then this is an endless loop |
1658 | // - No transformation can be done. |
1659 | |
1660 | const TypeInteger* incr_t = gvn->type(orig_incr)->is_integer(iv_bt); |
1661 | if (limit_t->hi_as_long() > incr_t->hi_as_long()) { |
1662 | // if the limit can have a higher value than the increment (before the phi) |
1663 | return false; |
1664 | } |
1665 | } |
1666 | |
1667 | Node *init_trip = phi->in(LoopNode::EntryControl); |
1668 | |
1669 | // If iv trunc type is smaller than int, check for possible wrap. |
1670 | if (!TypeInteger::bottom(iv_bt)->higher_equal(iv_trunc_t)) { |
1671 | assert(trunc1 != NULL, "must have found some truncation")do { if (!(trunc1 != __null)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1671, "assert(" "trunc1 != __null" ") failed", "must have found some truncation" ); ::breakpoint(); } } while (0); |
1672 | |
1673 | // Get a better type for the phi (filtered thru if's) |
1674 | const TypeInteger* phi_ft = filtered_type(phi); |
1675 | |
1676 | // Can iv take on a value that will wrap? |
1677 | // |
1678 | // Ensure iv's limit is not within "stride" of the wrap value. |
1679 | // |
1680 | // Example for "short" type |
1681 | // Truncation ensures value is in the range -32768..32767 (iv_trunc_t) |
1682 | // If the stride is +10, then the last value of the induction |
1683 | // variable before the increment (phi_ft->_hi) must be |
1684 | // <= 32767 - 10 and (phi_ft->_lo) must be >= -32768 to |
1685 | // ensure no truncation occurs after the increment. |
1686 | |
1687 | if (stride_con > 0) { |
1688 | if (iv_trunc_t->hi_as_long() - phi_ft->hi_as_long() < stride_con || |
1689 | iv_trunc_t->lo_as_long() > phi_ft->lo_as_long()) { |
1690 | return false; // truncation may occur |
1691 | } |
1692 | } else if (stride_con < 0) { |
1693 | if (iv_trunc_t->lo_as_long() - phi_ft->lo_as_long() > stride_con || |
1694 | iv_trunc_t->hi_as_long() < phi_ft->hi_as_long()) { |
1695 | return false; // truncation may occur |
1696 | } |
1697 | } |
1698 | // No possibility of wrap so truncation can be discarded |
1699 | // Promote iv type to Int |
1700 | } else { |
1701 | assert(trunc1 == NULL && trunc2 == NULL, "no truncation for int")do { if (!(trunc1 == __null && trunc2 == __null)) { ( *g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1701, "assert(" "trunc1 == __null && trunc2 == __null" ") failed", "no truncation for int"); ::breakpoint(); } } while (0); |
1702 | } |
1703 | |
1704 | if (!condition_stride_ok(bt, stride_con)) { |
1705 | return false; |
1706 | } |
1707 | |
1708 | const TypeInteger* init_t = gvn->type(init_trip)->is_integer(iv_bt); |
1709 | |
1710 | if (stride_con > 0) { |
1711 | if (init_t->lo_as_long() > max_signed_integer(iv_bt) - stride_con) { |
1712 | return false; // cyclic loop |
1713 | } |
1714 | } else { |
1715 | if (init_t->hi_as_long() < min_signed_integer(iv_bt) - stride_con) { |
1716 | return false; // cyclic loop |
1717 | } |
1718 | } |
1719 | |
1720 | if (phi_incr != NULL__null && bt != BoolTest::ne) { |
1721 | // check if there is a possiblity of IV overflowing after the first increment |
1722 | if (stride_con > 0) { |
1723 | if (init_t->hi_as_long() > max_signed_integer(iv_bt) - stride_con) { |
1724 | return false; |
1725 | } |
1726 | } else { |
1727 | if (init_t->lo_as_long() < min_signed_integer(iv_bt) - stride_con) { |
1728 | return false; |
1729 | } |
1730 | } |
1731 | } |
1732 | |
1733 | // ================================================= |
1734 | // ---- SUCCESS! Found A Trip-Counted Loop! ----- |
1735 | // |
1736 | assert(x->Opcode() == Op_Loop || x->Opcode() == Op_LongCountedLoop, "regular loops only")do { if (!(x->Opcode() == Op_Loop || x->Opcode() == Op_LongCountedLoop )) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1736, "assert(" "x->Opcode() == Op_Loop || x->Opcode() == Op_LongCountedLoop" ") failed", "regular loops only"); ::breakpoint(); } } while (0); |
1737 | C->print_method(PHASE_BEFORE_CLOOPS, 3); |
1738 | |
1739 | // =================================================== |
1740 | // Generate loop limit check to avoid integer overflow |
1741 | // in cases like next (cyclic loops): |
1742 | // |
1743 | // for (i=0; i <= max_jint; i++) {} |
1744 | // for (i=0; i < max_jint; i+=2) {} |
1745 | // |
1746 | // |
1747 | // Limit check predicate depends on the loop test: |
1748 | // |
1749 | // for(;i != limit; i++) --> limit <= (max_jint) |
1750 | // for(;i < limit; i+=stride) --> limit <= (max_jint - stride + 1) |
1751 | // for(;i <= limit; i+=stride) --> limit <= (max_jint - stride ) |
1752 | // |
1753 | |
1754 | // Check if limit is excluded to do more precise int overflow check. |
1755 | bool incl_limit = (bt == BoolTest::le || bt == BoolTest::ge); |
1756 | jlong stride_m = stride_con - (incl_limit ? 0 : (stride_con > 0 ? 1 : -1)); |
1757 | |
1758 | // If compare points directly to the phi we need to adjust |
1759 | // the compare so that it points to the incr. Limit have |
1760 | // to be adjusted to keep trip count the same and the |
1761 | // adjusted limit should be checked for int overflow. |
1762 | Node* adjusted_limit = limit; |
1763 | if (phi_incr != NULL__null) { |
1764 | stride_m += stride_con; |
1765 | } |
1766 | |
1767 | Node *init_control = x->in(LoopNode::EntryControl); |
1768 | |
1769 | int sov = check_stride_overflow(stride_m, limit_t, iv_bt); |
1770 | // If sov==0, limit's type always satisfies the condition, for |
1771 | // example, when it is an array length. |
1772 | if (sov != 0) { |
1773 | if (sov < 0) { |
1774 | return false; // Bailout: integer overflow is certain. |
1775 | } |
1776 | assert(!x->as_Loop()->is_loop_nest_inner_loop(), "loop was transformed")do { if (!(!x->as_Loop()->is_loop_nest_inner_loop())) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1776, "assert(" "!x->as_Loop()->is_loop_nest_inner_loop()" ") failed", "loop was transformed"); ::breakpoint(); } } while (0); |
1777 | // Generate loop's limit check. |
1778 | // Loop limit check predicate should be near the loop. |
1779 | ProjNode *limit_check_proj = find_predicate_insertion_point(init_control, Deoptimization::Reason_loop_limit_check); |
1780 | if (!limit_check_proj) { |
1781 | // The limit check predicate is not generated if this method trapped here before. |
1782 | #ifdef ASSERT1 |
1783 | if (TraceLoopLimitCheck) { |
1784 | tty->print("missing loop limit check:"); |
1785 | loop->dump_head(); |
1786 | x->dump(1); |
1787 | } |
1788 | #endif |
1789 | return false; |
1790 | } |
1791 | |
1792 | IfNode* check_iff = limit_check_proj->in(0)->as_If(); |
1793 | |
1794 | if (!is_dominator(get_ctrl(limit), check_iff->in(0))) { |
1795 | return false; |
1796 | } |
1797 | |
1798 | Node* cmp_limit; |
1799 | Node* bol; |
1800 | |
1801 | if (stride_con > 0) { |
1802 | cmp_limit = CmpNode::make(limit, _igvn.integercon(max_signed_integer(iv_bt) - stride_m, iv_bt), iv_bt); |
1803 | bol = new BoolNode(cmp_limit, BoolTest::le); |
1804 | } else { |
1805 | cmp_limit = CmpNode::make(limit, _igvn.integercon(min_signed_integer(iv_bt) - stride_m, iv_bt), iv_bt); |
1806 | bol = new BoolNode(cmp_limit, BoolTest::ge); |
1807 | } |
1808 | |
1809 | insert_loop_limit_check(limit_check_proj, cmp_limit, bol); |
1810 | } |
1811 | |
1812 | // Now we need to canonicalize loop condition. |
1813 | if (bt == BoolTest::ne) { |
1814 | assert(stride_con == 1 || stride_con == -1, "simple increment only")do { if (!(stride_con == 1 || stride_con == -1)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1814, "assert(" "stride_con == 1 || stride_con == -1" ") failed" , "simple increment only"); ::breakpoint(); } } while (0); |
1815 | if (stride_con > 0 && init_t->hi_as_long() < limit_t->lo_as_long()) { |
1816 | // 'ne' can be replaced with 'lt' only when init < limit. |
1817 | bt = BoolTest::lt; |
1818 | } else if (stride_con < 0 && init_t->lo_as_long() > limit_t->hi_as_long()) { |
1819 | // 'ne' can be replaced with 'gt' only when init > limit. |
1820 | bt = BoolTest::gt; |
1821 | } else { |
1822 | ProjNode *limit_check_proj = find_predicate_insertion_point(init_control, Deoptimization::Reason_loop_limit_check); |
1823 | if (!limit_check_proj) { |
1824 | // The limit check predicate is not generated if this method trapped here before. |
1825 | #ifdef ASSERT1 |
1826 | if (TraceLoopLimitCheck) { |
1827 | tty->print("missing loop limit check:"); |
1828 | loop->dump_head(); |
1829 | x->dump(1); |
1830 | } |
1831 | #endif |
1832 | return false; |
1833 | } |
1834 | IfNode* check_iff = limit_check_proj->in(0)->as_If(); |
1835 | |
1836 | if (!is_dominator(get_ctrl(limit), check_iff->in(0)) || |
1837 | !is_dominator(get_ctrl(init_trip), check_iff->in(0))) { |
1838 | return false; |
1839 | } |
1840 | |
1841 | Node* cmp_limit; |
1842 | Node* bol; |
1843 | |
1844 | if (stride_con > 0) { |
1845 | cmp_limit = CmpNode::make(init_trip, limit, iv_bt); |
1846 | bol = new BoolNode(cmp_limit, BoolTest::lt); |
1847 | } else { |
1848 | cmp_limit = CmpNode::make(init_trip, limit, iv_bt); |
1849 | bol = new BoolNode(cmp_limit, BoolTest::gt); |
1850 | } |
1851 | |
1852 | insert_loop_limit_check(limit_check_proj, cmp_limit, bol); |
1853 | |
1854 | if (stride_con > 0) { |
1855 | // 'ne' can be replaced with 'lt' only when init < limit. |
1856 | bt = BoolTest::lt; |
1857 | } else if (stride_con < 0) { |
1858 | // 'ne' can be replaced with 'gt' only when init > limit. |
1859 | bt = BoolTest::gt; |
1860 | } |
1861 | } |
1862 | } |
1863 | |
1864 | #ifdef ASSERT1 |
1865 | if (iv_bt == T_INT && |
1866 | !x->as_Loop()->is_loop_nest_inner_loop() && |
1867 | StressLongCountedLoop > 0 && |
1868 | trunc1 == NULL__null && |
1869 | convert_to_long_loop(cmp, phi, loop)) { |
1870 | return false; |
1871 | } |
1872 | #endif |
1873 | |
1874 | if (phi_incr != NULL__null) { |
1875 | // If compare points directly to the phi we need to adjust |
1876 | // the compare so that it points to the incr. Limit have |
1877 | // to be adjusted to keep trip count the same and we |
1878 | // should avoid int overflow. |
1879 | // |
1880 | // i = init; do {} while(i++ < limit); |
1881 | // is converted to |
1882 | // i = init; do {} while(++i < limit+1); |
1883 | // |
1884 | adjusted_limit = gvn->transform(AddNode::make(limit, stride, iv_bt)); |
1885 | } |
1886 | |
1887 | if (incl_limit) { |
1888 | // The limit check guaranties that 'limit <= (max_jint - stride)' so |
1889 | // we can convert 'i <= limit' to 'i < limit+1' since stride != 0. |
1890 | // |
1891 | Node* one = (stride_con > 0) ? gvn->integercon( 1, iv_bt) : gvn->integercon(-1, iv_bt); |
1892 | adjusted_limit = gvn->transform(AddNode::make(adjusted_limit, one, iv_bt)); |
1893 | if (bt == BoolTest::le) |
1894 | bt = BoolTest::lt; |
1895 | else if (bt == BoolTest::ge) |
1896 | bt = BoolTest::gt; |
1897 | else |
1898 | ShouldNotReachHere()do { (*g_assert_poison) = 'X';; report_should_not_reach_here( "/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1898); ::breakpoint(); } while (0); |
1899 | } |
1900 | set_subtree_ctrl(adjusted_limit, false); |
1901 | |
1902 | if (iv_bt == T_INT && LoopStripMiningIter == 0) { |
1903 | // Check for SafePoint on backedge and remove |
1904 | Node *sfpt = x->in(LoopNode::LoopBackControl); |
1905 | if (sfpt->Opcode() == Op_SafePoint && is_deleteable_safept(sfpt)) { |
1906 | lazy_replace( sfpt, iftrue ); |
1907 | if (loop->_safepts != NULL__null) { |
1908 | loop->_safepts->yank(sfpt); |
1909 | } |
1910 | loop->_tail = iftrue; |
1911 | } |
1912 | } |
1913 | |
1914 | // Build a canonical trip test. |
1915 | // Clone code, as old values may be in use. |
1916 | incr = incr->clone(); |
1917 | incr->set_req(1,phi); |
1918 | incr->set_req(2,stride); |
1919 | incr = _igvn.register_new_node_with_optimizer(incr); |
1920 | set_early_ctrl(incr, false); |
1921 | _igvn.rehash_node_delayed(phi); |
1922 | phi->set_req_X( LoopNode::LoopBackControl, incr, &_igvn ); |
1923 | |
1924 | // If phi type is more restrictive than Int, raise to |
1925 | // Int to prevent (almost) infinite recursion in igvn |
1926 | // which can only handle integer types for constants or minint..maxint. |
1927 | if (!TypeInteger::bottom(iv_bt)->higher_equal(phi->bottom_type())) { |
1928 | Node* nphi = PhiNode::make(phi->in(0), phi->in(LoopNode::EntryControl), TypeInteger::bottom(iv_bt)); |
1929 | nphi->set_req(LoopNode::LoopBackControl, phi->in(LoopNode::LoopBackControl)); |
1930 | nphi = _igvn.register_new_node_with_optimizer(nphi); |
1931 | set_ctrl(nphi, get_ctrl(phi)); |
1932 | _igvn.replace_node(phi, nphi); |
1933 | phi = nphi->as_Phi(); |
1934 | } |
1935 | cmp = cmp->clone(); |
1936 | cmp->set_req(1,incr); |
1937 | cmp->set_req(2, adjusted_limit); |
1938 | cmp = _igvn.register_new_node_with_optimizer(cmp); |
1939 | set_ctrl(cmp, iff->in(0)); |
1940 | |
1941 | test = test->clone()->as_Bool(); |
1942 | (*(BoolTest*)&test->_test)._test = bt; |
1943 | test->set_req(1,cmp); |
1944 | _igvn.register_new_node_with_optimizer(test); |
1945 | set_ctrl(test, iff->in(0)); |
1946 | |
1947 | // Replace the old IfNode with a new LoopEndNode |
1948 | Node *lex = _igvn.register_new_node_with_optimizer(BaseCountedLoopEndNode::make(iff->in(0), test, cl_prob, iff->as_If()->_fcnt, iv_bt)); |
1949 | IfNode *le = lex->as_If(); |
1950 | uint dd = dom_depth(iff); |
1951 | set_idom(le, le->in(0), dd); // Update dominance for loop exit |
1952 | set_loop(le, loop); |
1953 | |
1954 | // Get the loop-exit control |
1955 | Node *iffalse = iff->as_If()->proj_out(!(iftrue_op == Op_IfTrue)); |
1956 | |
1957 | // Need to swap loop-exit and loop-back control? |
1958 | if (iftrue_op == Op_IfFalse) { |
1959 | Node *ift2=_igvn.register_new_node_with_optimizer(new IfTrueNode (le)); |
1960 | Node *iff2=_igvn.register_new_node_with_optimizer(new IfFalseNode(le)); |
1961 | |
1962 | loop->_tail = back_control = ift2; |
1963 | set_loop(ift2, loop); |
1964 | set_loop(iff2, get_loop(iffalse)); |
1965 | |
1966 | // Lazy update of 'get_ctrl' mechanism. |
1967 | lazy_replace(iffalse, iff2); |
1968 | lazy_replace(iftrue, ift2); |
1969 | |
1970 | // Swap names |
1971 | iffalse = iff2; |
1972 | iftrue = ift2; |
1973 | } else { |
1974 | _igvn.rehash_node_delayed(iffalse); |
1975 | _igvn.rehash_node_delayed(iftrue); |
1976 | iffalse->set_req_X( 0, le, &_igvn ); |
1977 | iftrue ->set_req_X( 0, le, &_igvn ); |
1978 | } |
1979 | |
1980 | set_idom(iftrue, le, dd+1); |
1981 | set_idom(iffalse, le, dd+1); |
1982 | assert(iff->outcnt() == 0, "should be dead now")do { if (!(iff->outcnt() == 0)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 1982, "assert(" "iff->outcnt() == 0" ") failed", "should be dead now" ); ::breakpoint(); } } while (0); |
1983 | lazy_replace( iff, le ); // fix 'get_ctrl' |
1984 | |
1985 | Node *sfpt2 = le->in(0); |
1986 | |
1987 | Node* entry_control = init_control; |
1988 | bool strip_mine_loop = iv_bt == T_INT && |
1989 | LoopStripMiningIter > 1 && |
1990 | loop->_child == NULL__null && |
1991 | sfpt2->Opcode() == Op_SafePoint && |
1992 | !loop->_has_call; |
1993 | IdealLoopTree* outer_ilt = NULL__null; |
1994 | if (strip_mine_loop) { |
1995 | outer_ilt = create_outer_strip_mined_loop(test, cmp, init_control, loop, |
1996 | cl_prob, le->_fcnt, entry_control, |
1997 | iffalse); |
1998 | } |
1999 | |
2000 | // Now setup a new CountedLoopNode to replace the existing LoopNode |
2001 | BaseCountedLoopNode *l = BaseCountedLoopNode::make(entry_control, back_control, iv_bt); |
2002 | l->set_unswitch_count(x->as_Loop()->unswitch_count()); // Preserve |
2003 | // The following assert is approximately true, and defines the intention |
2004 | // of can_be_counted_loop. It fails, however, because phase->type |
2005 | // is not yet initialized for this loop and its parts. |
2006 | //assert(l->can_be_counted_loop(this), "sanity"); |
2007 | _igvn.register_new_node_with_optimizer(l); |
2008 | set_loop(l, loop); |
2009 | loop->_head = l; |
2010 | // Fix all data nodes placed at the old loop head. |
2011 | // Uses the lazy-update mechanism of 'get_ctrl'. |
2012 | lazy_replace( x, l ); |
2013 | set_idom(l, entry_control, dom_depth(entry_control) + 1); |
2014 | |
2015 | if (iv_bt == T_INT && (LoopStripMiningIter == 0 || strip_mine_loop)) { |
2016 | // Check for immediately preceding SafePoint and remove |
2017 | if (sfpt2->Opcode() == Op_SafePoint && (LoopStripMiningIter != 0 || is_deleteable_safept(sfpt2))) { |
2018 | if (strip_mine_loop) { |
2019 | Node* outer_le = outer_ilt->_tail->in(0); |
2020 | Node* sfpt = sfpt2->clone(); |
2021 | sfpt->set_req(0, iffalse); |
2022 | outer_le->set_req(0, sfpt); |
2023 | |
2024 | Node* polladdr = sfpt->in(TypeFunc::Parms); |
2025 | if (polladdr != nullptr && polladdr->is_Load()) { |
2026 | // Polling load should be pinned outside inner loop. |
2027 | Node* new_polladdr = polladdr->clone(); |
2028 | new_polladdr->set_req(0, iffalse); |
2029 | _igvn.register_new_node_with_optimizer(new_polladdr, polladdr); |
2030 | set_ctrl(new_polladdr, iffalse); |
2031 | sfpt->set_req(TypeFunc::Parms, new_polladdr); |
2032 | } |
2033 | // When this code runs, loop bodies have not yet been populated. |
2034 | const bool body_populated = false; |
2035 | register_control(sfpt, outer_ilt, iffalse, body_populated); |
2036 | set_idom(outer_le, sfpt, dom_depth(sfpt)); |
2037 | } |
2038 | lazy_replace( sfpt2, sfpt2->in(TypeFunc::Control)); |
2039 | if (loop->_safepts != NULL__null) { |
2040 | loop->_safepts->yank(sfpt2); |
2041 | } |
2042 | } |
2043 | } |
2044 | |
2045 | #ifdef ASSERT1 |
2046 | assert(l->is_valid_counted_loop(iv_bt), "counted loop shape is messed up")do { if (!(l->is_valid_counted_loop(iv_bt))) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2046, "assert(" "l->is_valid_counted_loop(iv_bt)" ") failed" , "counted loop shape is messed up"); ::breakpoint(); } } while (0); |
2047 | assert(l == loop->_head && l->phi() == phi && l->loopexit_or_null() == lex, "" )do { if (!(l == loop->_head && l->phi() == phi && l->loopexit_or_null() == lex)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2047, "assert(" "l == loop->_head && l->phi() == phi && l->loopexit_or_null() == lex" ") failed", ""); ::breakpoint(); } } while (0); |
2048 | #endif |
2049 | #ifndef PRODUCT |
2050 | if (TraceLoopOpts) { |
2051 | tty->print("Counted "); |
2052 | loop->dump_head(); |
2053 | } |
2054 | #endif |
2055 | |
2056 | C->print_method(PHASE_AFTER_CLOOPS, 3); |
2057 | |
2058 | // Capture bounds of the loop in the induction variable Phi before |
2059 | // subsequent transformation (iteration splitting) obscures the |
2060 | // bounds |
2061 | l->phi()->as_Phi()->set_type(l->phi()->Value(&_igvn)); |
2062 | |
2063 | if (strip_mine_loop) { |
2064 | l->mark_strip_mined(); |
2065 | l->verify_strip_mined(1); |
2066 | outer_ilt->_head->as_Loop()->verify_strip_mined(1); |
2067 | loop = outer_ilt; |
2068 | } |
2069 | |
2070 | #ifndef PRODUCT |
2071 | if (x->as_Loop()->is_loop_nest_inner_loop() && iv_bt == T_LONG) { |
2072 | Atomic::inc(&_long_loop_counted_loops); |
2073 | } |
2074 | #endif |
2075 | if (iv_bt == T_LONG && x->as_Loop()->is_loop_nest_outer_loop()) { |
2076 | l->mark_loop_nest_outer_loop(); |
2077 | } |
2078 | |
2079 | return true; |
2080 | } |
2081 | |
2082 | //----------------------exact_limit------------------------------------------- |
2083 | Node* PhaseIdealLoop::exact_limit( IdealLoopTree *loop ) { |
2084 | assert(loop->_head->is_CountedLoop(), "")do { if (!(loop->_head->is_CountedLoop())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2084, "assert(" "loop->_head->is_CountedLoop()" ") failed" , ""); ::breakpoint(); } } while (0); |
2085 | CountedLoopNode *cl = loop->_head->as_CountedLoop(); |
2086 | assert(cl->is_valid_counted_loop(T_INT), "")do { if (!(cl->is_valid_counted_loop(T_INT))) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2086, "assert(" "cl->is_valid_counted_loop(T_INT)" ") failed" , ""); ::breakpoint(); } } while (0); |
2087 | |
2088 | if (ABS(cl->stride_con()) == 1 || |
2089 | cl->limit()->Opcode() == Op_LoopLimit) { |
2090 | // Old code has exact limit (it could be incorrect in case of int overflow). |
2091 | // Loop limit is exact with stride == 1. And loop may already have exact limit. |
2092 | return cl->limit(); |
2093 | } |
2094 | Node *limit = NULL__null; |
2095 | #ifdef ASSERT1 |
2096 | BoolTest::mask bt = cl->loopexit()->test_trip(); |
2097 | assert(bt == BoolTest::lt || bt == BoolTest::gt, "canonical test is expected")do { if (!(bt == BoolTest::lt || bt == BoolTest::gt)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2097, "assert(" "bt == BoolTest::lt || bt == BoolTest::gt" ") failed" , "canonical test is expected"); ::breakpoint(); } } while (0 ); |
2098 | #endif |
2099 | if (cl->has_exact_trip_count()) { |
2100 | // Simple case: loop has constant boundaries. |
2101 | // Use jlongs to avoid integer overflow. |
2102 | int stride_con = cl->stride_con(); |
2103 | jlong init_con = cl->init_trip()->get_int(); |
2104 | jlong limit_con = cl->limit()->get_int(); |
2105 | julong trip_cnt = cl->trip_count(); |
2106 | jlong final_con = init_con + trip_cnt*stride_con; |
2107 | int final_int = (int)final_con; |
2108 | // The final value should be in integer range since the loop |
2109 | // is counted and the limit was checked for overflow. |
2110 | assert(final_con == (jlong)final_int, "final value should be integer")do { if (!(final_con == (jlong)final_int)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2110, "assert(" "final_con == (jlong)final_int" ") failed", "final value should be integer"); ::breakpoint(); } } while ( 0); |
2111 | limit = _igvn.intcon(final_int); |
2112 | } else { |
2113 | // Create new LoopLimit node to get exact limit (final iv value). |
2114 | limit = new LoopLimitNode(C, cl->init_trip(), cl->limit(), cl->stride()); |
2115 | register_new_node(limit, cl->in(LoopNode::EntryControl)); |
2116 | } |
2117 | assert(limit != NULL, "sanity")do { if (!(limit != __null)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2117, "assert(" "limit != __null" ") failed", "sanity"); :: breakpoint(); } } while (0); |
2118 | return limit; |
2119 | } |
2120 | |
2121 | //------------------------------Ideal------------------------------------------ |
2122 | // Return a node which is more "ideal" than the current node. |
2123 | // Attempt to convert into a counted-loop. |
2124 | Node *LoopNode::Ideal(PhaseGVN *phase, bool can_reshape) { |
2125 | if (!can_be_counted_loop(phase) && !is_OuterStripMinedLoop()) { |
2126 | phase->C->set_major_progress(); |
2127 | } |
2128 | return RegionNode::Ideal(phase, can_reshape); |
2129 | } |
2130 | |
2131 | #ifdef ASSERT1 |
2132 | void LoopNode::verify_strip_mined(int expect_skeleton) const { |
2133 | const OuterStripMinedLoopNode* outer = NULL__null; |
2134 | const CountedLoopNode* inner = NULL__null; |
2135 | if (is_strip_mined()) { |
2136 | if (!is_valid_counted_loop(T_INT)) { |
2137 | return; // Skip malformed counted loop |
2138 | } |
2139 | assert(is_CountedLoop(), "no Loop should be marked strip mined")do { if (!(is_CountedLoop())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2139, "assert(" "is_CountedLoop()" ") failed", "no Loop should be marked strip mined" ); ::breakpoint(); } } while (0); |
2140 | inner = as_CountedLoop(); |
2141 | outer = inner->in(LoopNode::EntryControl)->as_OuterStripMinedLoop(); |
2142 | } else if (is_OuterStripMinedLoop()) { |
2143 | outer = this->as_OuterStripMinedLoop(); |
2144 | inner = outer->unique_ctrl_out()->as_CountedLoop(); |
2145 | assert(inner->is_valid_counted_loop(T_INT) && inner->is_strip_mined(), "OuterStripMinedLoop should have been removed")do { if (!(inner->is_valid_counted_loop(T_INT) && inner ->is_strip_mined())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2145, "assert(" "inner->is_valid_counted_loop(T_INT) && inner->is_strip_mined()" ") failed", "OuterStripMinedLoop should have been removed"); ::breakpoint(); } } while (0); |
2146 | assert(!is_strip_mined(), "outer loop shouldn't be marked strip mined")do { if (!(!is_strip_mined())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2146, "assert(" "!is_strip_mined()" ") failed", "outer loop shouldn't be marked strip mined" ); ::breakpoint(); } } while (0); |
2147 | } |
2148 | if (inner != NULL__null || outer != NULL__null) { |
2149 | assert(inner != NULL && outer != NULL, "missing loop in strip mined nest")do { if (!(inner != __null && outer != __null)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2149, "assert(" "inner != __null && outer != __null" ") failed", "missing loop in strip mined nest"); ::breakpoint (); } } while (0); |
2150 | Node* outer_tail = outer->in(LoopNode::LoopBackControl); |
2151 | Node* outer_le = outer_tail->in(0); |
2152 | assert(outer_le->Opcode() == Op_OuterStripMinedLoopEnd, "tail of outer loop should be an If")do { if (!(outer_le->Opcode() == Op_OuterStripMinedLoopEnd )) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2152, "assert(" "outer_le->Opcode() == Op_OuterStripMinedLoopEnd" ") failed", "tail of outer loop should be an If"); ::breakpoint (); } } while (0); |
2153 | Node* sfpt = outer_le->in(0); |
2154 | assert(sfpt->Opcode() == Op_SafePoint, "where's the safepoint?")do { if (!(sfpt->Opcode() == Op_SafePoint)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2154, "assert(" "sfpt->Opcode() == Op_SafePoint" ") failed" , "where's the safepoint?"); ::breakpoint(); } } while (0); |
2155 | Node* inner_out = sfpt->in(0); |
2156 | CountedLoopEndNode* cle = inner_out->in(0)->as_CountedLoopEnd(); |
2157 | assert(cle == inner->loopexit_or_null(), "mismatch")do { if (!(cle == inner->loopexit_or_null())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2157, "assert(" "cle == inner->loopexit_or_null()" ") failed" , "mismatch"); ::breakpoint(); } } while (0); |
2158 | bool has_skeleton = outer_le->in(1)->bottom_type()->singleton() && outer_le->in(1)->bottom_type()->is_int()->get_con() == 0; |
2159 | if (has_skeleton) { |
2160 | assert(expect_skeleton == 1 || expect_skeleton == -1, "unexpected skeleton node")do { if (!(expect_skeleton == 1 || expect_skeleton == -1)) { ( *g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2160, "assert(" "expect_skeleton == 1 || expect_skeleton == -1" ") failed", "unexpected skeleton node"); ::breakpoint(); } } while (0); |
2161 | assert(outer->outcnt() == 2, "only control nodes")do { if (!(outer->outcnt() == 2)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2161, "assert(" "outer->outcnt() == 2" ") failed", "only control nodes" ); ::breakpoint(); } } while (0); |
2162 | } else { |
2163 | assert(expect_skeleton == 0 || expect_skeleton == -1, "no skeleton node?")do { if (!(expect_skeleton == 0 || expect_skeleton == -1)) { ( *g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2163, "assert(" "expect_skeleton == 0 || expect_skeleton == -1" ") failed", "no skeleton node?"); ::breakpoint(); } } while ( 0); |
2164 | uint phis = 0; |
2165 | uint be_loads = 0; |
2166 | Node* be = inner->in(LoopNode::LoopBackControl); |
2167 | for (DUIterator_Fast imax, i = inner->fast_outs(imax); i < imax; i++) { |
2168 | Node* u = inner->fast_out(i); |
2169 | if (u->is_Phi()) { |
2170 | phis++; |
2171 | for (DUIterator_Fast jmax, j = be->fast_outs(jmax); j < jmax; j++) { |
2172 | Node* n = be->fast_out(j); |
2173 | if (n->is_Load()) { |
2174 | assert(n->in(0) == be || n->find_prec_edge(be) > 0, "should be on the backedge")do { if (!(n->in(0) == be || n->find_prec_edge(be) > 0)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2174, "assert(" "n->in(0) == be || n->find_prec_edge(be) > 0" ") failed", "should be on the backedge"); ::breakpoint(); } } while (0); |
2175 | do { |
2176 | n = n->raw_out(0); |
2177 | } while (!n->is_Phi()); |
2178 | if (n == u) { |
2179 | be_loads++; |
2180 | break; |
2181 | } |
2182 | } |
2183 | } |
2184 | } |
2185 | } |
2186 | assert(be_loads <= phis, "wrong number phis that depends on a pinned load")do { if (!(be_loads <= phis)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2186, "assert(" "be_loads <= phis" ") failed", "wrong number phis that depends on a pinned load" ); ::breakpoint(); } } while (0); |
2187 | for (DUIterator_Fast imax, i = outer->fast_outs(imax); i < imax; i++) { |
2188 | Node* u = outer->fast_out(i); |
2189 | assert(u == outer || u == inner || u->is_Phi(), "nothing between inner and outer loop")do { if (!(u == outer || u == inner || u->is_Phi())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2189, "assert(" "u == outer || u == inner || u->is_Phi()" ") failed", "nothing between inner and outer loop"); ::breakpoint (); } } while (0); |
2190 | } |
2191 | uint stores = 0; |
2192 | for (DUIterator_Fast imax, i = inner_out->fast_outs(imax); i < imax; i++) { |
2193 | Node* u = inner_out->fast_out(i); |
2194 | if (u->is_Store()) { |
2195 | stores++; |
2196 | } |
2197 | } |
2198 | // Late optimization of loads on backedge can cause Phi of outer loop to be eliminated but Phi of inner loop is |
2199 | // not guaranteed to be optimized out. |
2200 | assert(outer->outcnt() >= phis + 2 - be_loads && outer->outcnt() <= phis + 2 + stores + 1, "only phis")do { if (!(outer->outcnt() >= phis + 2 - be_loads && outer->outcnt() <= phis + 2 + stores + 1)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2200, "assert(" "outer->outcnt() >= phis + 2 - be_loads && outer->outcnt() <= phis + 2 + stores + 1" ") failed", "only phis"); ::breakpoint(); } } while (0); |
2201 | } |
2202 | assert(sfpt->outcnt() == 1, "no data node")do { if (!(sfpt->outcnt() == 1)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2202, "assert(" "sfpt->outcnt() == 1" ") failed", "no data node" ); ::breakpoint(); } } while (0); |
2203 | assert(outer_tail->outcnt() == 1 || !has_skeleton, "no data node")do { if (!(outer_tail->outcnt() == 1 || !has_skeleton)) { ( *g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2203, "assert(" "outer_tail->outcnt() == 1 || !has_skeleton" ") failed", "no data node"); ::breakpoint(); } } while (0); |
2204 | } |
2205 | } |
2206 | #endif |
2207 | |
2208 | //============================================================================= |
2209 | //------------------------------Ideal------------------------------------------ |
2210 | // Return a node which is more "ideal" than the current node. |
2211 | // Attempt to convert into a counted-loop. |
2212 | Node *CountedLoopNode::Ideal(PhaseGVN *phase, bool can_reshape) { |
2213 | return RegionNode::Ideal(phase, can_reshape); |
2214 | } |
2215 | |
2216 | //------------------------------dump_spec-------------------------------------- |
2217 | // Dump special per-node info |
2218 | #ifndef PRODUCT |
2219 | void CountedLoopNode::dump_spec(outputStream *st) const { |
2220 | LoopNode::dump_spec(st); |
2221 | if (stride_is_con()) { |
2222 | st->print("stride: %d ",stride_con()); |
2223 | } |
2224 | if (is_pre_loop ()) st->print("pre of N%d" , _main_idx); |
2225 | if (is_main_loop()) st->print("main of N%d", _idx); |
2226 | if (is_post_loop()) st->print("post of N%d", _main_idx); |
2227 | if (is_strip_mined()) st->print(" strip mined"); |
2228 | } |
2229 | #endif |
2230 | |
2231 | //============================================================================= |
2232 | jlong BaseCountedLoopEndNode::stride_con() const { |
2233 | return stride()->bottom_type()->is_integer(bt())->get_con_as_long(bt()); |
2234 | } |
2235 | |
2236 | |
2237 | BaseCountedLoopEndNode* BaseCountedLoopEndNode::make(Node* control, Node* test, float prob, float cnt, BasicType bt) { |
2238 | if (bt == T_INT) { |
2239 | return new CountedLoopEndNode(control, test, prob, cnt); |
2240 | } |
2241 | assert(bt == T_LONG, "unsupported")do { if (!(bt == T_LONG)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2241, "assert(" "bt == T_LONG" ") failed", "unsupported"); :: breakpoint(); } } while (0); |
2242 | return new LongCountedLoopEndNode(control, test, prob, cnt); |
2243 | } |
2244 | |
2245 | //============================================================================= |
2246 | //------------------------------Value----------------------------------------- |
2247 | const Type* LoopLimitNode::Value(PhaseGVN* phase) const { |
2248 | const Type* init_t = phase->type(in(Init)); |
2249 | const Type* limit_t = phase->type(in(Limit)); |
2250 | const Type* stride_t = phase->type(in(Stride)); |
2251 | // Either input is TOP ==> the result is TOP |
2252 | if (init_t == Type::TOP) return Type::TOP; |
2253 | if (limit_t == Type::TOP) return Type::TOP; |
2254 | if (stride_t == Type::TOP) return Type::TOP; |
2255 | |
2256 | int stride_con = stride_t->is_int()->get_con(); |
2257 | if (stride_con == 1) |
2258 | return bottom_type(); // Identity |
2259 | |
2260 | if (init_t->is_int()->is_con() && limit_t->is_int()->is_con()) { |
2261 | // Use jlongs to avoid integer overflow. |
2262 | jlong init_con = init_t->is_int()->get_con(); |
2263 | jlong limit_con = limit_t->is_int()->get_con(); |
2264 | int stride_m = stride_con - (stride_con > 0 ? 1 : -1); |
2265 | jlong trip_count = (limit_con - init_con + stride_m)/stride_con; |
2266 | jlong final_con = init_con + stride_con*trip_count; |
2267 | int final_int = (int)final_con; |
2268 | // The final value should be in integer range since the loop |
2269 | // is counted and the limit was checked for overflow. |
2270 | assert(final_con == (jlong)final_int, "final value should be integer")do { if (!(final_con == (jlong)final_int)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2270, "assert(" "final_con == (jlong)final_int" ") failed", "final value should be integer"); ::breakpoint(); } } while ( 0); |
2271 | return TypeInt::make(final_int); |
2272 | } |
2273 | |
2274 | return bottom_type(); // TypeInt::INT |
2275 | } |
2276 | |
2277 | //------------------------------Ideal------------------------------------------ |
2278 | // Return a node which is more "ideal" than the current node. |
2279 | Node *LoopLimitNode::Ideal(PhaseGVN *phase, bool can_reshape) { |
2280 | if (phase->type(in(Init)) == Type::TOP || |
2281 | phase->type(in(Limit)) == Type::TOP || |
2282 | phase->type(in(Stride)) == Type::TOP) |
2283 | return NULL__null; // Dead |
2284 | |
2285 | int stride_con = phase->type(in(Stride))->is_int()->get_con(); |
2286 | if (stride_con == 1) |
2287 | return NULL__null; // Identity |
2288 | |
2289 | if (in(Init)->is_Con() && in(Limit)->is_Con()) |
2290 | return NULL__null; // Value |
2291 | |
2292 | // Delay following optimizations until all loop optimizations |
2293 | // done to keep Ideal graph simple. |
2294 | if (!can_reshape || !phase->C->post_loop_opts_phase()) { |
2295 | return NULL__null; |
2296 | } |
2297 | |
2298 | const TypeInt* init_t = phase->type(in(Init) )->is_int(); |
2299 | const TypeInt* limit_t = phase->type(in(Limit))->is_int(); |
2300 | int stride_p; |
2301 | jlong lim, ini; |
2302 | julong max; |
2303 | if (stride_con > 0) { |
2304 | stride_p = stride_con; |
2305 | lim = limit_t->_hi; |
2306 | ini = init_t->_lo; |
2307 | max = (julong)max_jint; |
2308 | } else { |
2309 | stride_p = -stride_con; |
2310 | lim = init_t->_hi; |
2311 | ini = limit_t->_lo; |
2312 | max = (julong)min_jint; |
2313 | } |
2314 | julong range = lim - ini + stride_p; |
2315 | if (range <= max) { |
2316 | // Convert to integer expression if it is not overflow. |
2317 | Node* stride_m = phase->intcon(stride_con - (stride_con > 0 ? 1 : -1)); |
2318 | Node *range = phase->transform(new SubINode(in(Limit), in(Init))); |
2319 | Node *bias = phase->transform(new AddINode(range, stride_m)); |
2320 | Node *trip = phase->transform(new DivINode(0, bias, in(Stride))); |
2321 | Node *span = phase->transform(new MulINode(trip, in(Stride))); |
2322 | return new AddINode(span, in(Init)); // exact limit |
2323 | } |
2324 | |
2325 | if (is_power_of_2(stride_p) || // divisor is 2^n |
2326 | !Matcher::has_match_rule(Op_LoopLimit)) { // or no specialized Mach node? |
2327 | // Convert to long expression to avoid integer overflow |
2328 | // and let igvn optimizer convert this division. |
2329 | // |
2330 | Node* init = phase->transform( new ConvI2LNode(in(Init))); |
2331 | Node* limit = phase->transform( new ConvI2LNode(in(Limit))); |
2332 | Node* stride = phase->longcon(stride_con); |
2333 | Node* stride_m = phase->longcon(stride_con - (stride_con > 0 ? 1 : -1)); |
2334 | |
2335 | Node *range = phase->transform(new SubLNode(limit, init)); |
2336 | Node *bias = phase->transform(new AddLNode(range, stride_m)); |
2337 | Node *span; |
2338 | if (stride_con > 0 && is_power_of_2(stride_p)) { |
2339 | // bias >= 0 if stride >0, so if stride is 2^n we can use &(-stride) |
2340 | // and avoid generating rounding for division. Zero trip guard should |
2341 | // guarantee that init < limit but sometimes the guard is missing and |
2342 | // we can get situation when init > limit. Note, for the empty loop |
2343 | // optimization zero trip guard is generated explicitly which leaves |
2344 | // only RCE predicate where exact limit is used and the predicate |
2345 | // will simply fail forcing recompilation. |
2346 | Node* neg_stride = phase->longcon(-stride_con); |
2347 | span = phase->transform(new AndLNode(bias, neg_stride)); |
2348 | } else { |
2349 | Node *trip = phase->transform(new DivLNode(0, bias, stride)); |
2350 | span = phase->transform(new MulLNode(trip, stride)); |
2351 | } |
2352 | // Convert back to int |
2353 | Node *span_int = phase->transform(new ConvL2INode(span)); |
2354 | return new AddINode(span_int, in(Init)); // exact limit |
2355 | } |
2356 | |
2357 | return NULL__null; // No progress |
2358 | } |
2359 | |
2360 | //------------------------------Identity--------------------------------------- |
2361 | // If stride == 1 return limit node. |
2362 | Node* LoopLimitNode::Identity(PhaseGVN* phase) { |
2363 | int stride_con = phase->type(in(Stride))->is_int()->get_con(); |
2364 | if (stride_con == 1 || stride_con == -1) |
2365 | return in(Limit); |
2366 | return this; |
2367 | } |
2368 | |
2369 | //============================================================================= |
2370 | //----------------------match_incr_with_optional_truncation-------------------- |
2371 | // Match increment with optional truncation: |
2372 | // CHAR: (i+1)&0x7fff, BYTE: ((i+1)<<8)>>8, or SHORT: ((i+1)<<16)>>16 |
2373 | // Return NULL for failure. Success returns the increment node. |
2374 | Node* CountedLoopNode::match_incr_with_optional_truncation(Node* expr, Node** trunc1, Node** trunc2, |
2375 | const TypeInteger** trunc_type, |
2376 | BasicType bt) { |
2377 | // Quick cutouts: |
2378 | if (expr == NULL__null || expr->req() != 3) return NULL__null; |
2379 | |
2380 | Node *t1 = NULL__null; |
2381 | Node *t2 = NULL__null; |
2382 | Node* n1 = expr; |
2383 | int n1op = n1->Opcode(); |
2384 | const TypeInteger* trunc_t = TypeInteger::bottom(bt); |
2385 | |
2386 | if (bt == T_INT) { |
2387 | // Try to strip (n1 & M) or (n1 << N >> N) from n1. |
2388 | if (n1op == Op_AndI && |
2389 | n1->in(2)->is_Con() && |
2390 | n1->in(2)->bottom_type()->is_int()->get_con() == 0x7fff) { |
2391 | // %%% This check should match any mask of 2**K-1. |
2392 | t1 = n1; |
2393 | n1 = t1->in(1); |
2394 | n1op = n1->Opcode(); |
2395 | trunc_t = TypeInt::CHAR; |
2396 | } else if (n1op == Op_RShiftI && |
2397 | n1->in(1) != NULL__null && |
2398 | n1->in(1)->Opcode() == Op_LShiftI && |
2399 | n1->in(2) == n1->in(1)->in(2) && |
2400 | n1->in(2)->is_Con()) { |
2401 | jint shift = n1->in(2)->bottom_type()->is_int()->get_con(); |
2402 | // %%% This check should match any shift in [1..31]. |
2403 | if (shift == 16 || shift == 8) { |
2404 | t1 = n1; |
2405 | t2 = t1->in(1); |
2406 | n1 = t2->in(1); |
2407 | n1op = n1->Opcode(); |
2408 | if (shift == 16) { |
2409 | trunc_t = TypeInt::SHORT; |
2410 | } else if (shift == 8) { |
2411 | trunc_t = TypeInt::BYTE; |
2412 | } |
2413 | } |
2414 | } |
2415 | } |
2416 | |
2417 | // If (maybe after stripping) it is an AddI, we won: |
2418 | if (n1op == Op_Add(bt)) { |
2419 | *trunc1 = t1; |
2420 | *trunc2 = t2; |
2421 | *trunc_type = trunc_t; |
2422 | return n1; |
2423 | } |
2424 | |
2425 | // failed |
2426 | return NULL__null; |
2427 | } |
2428 | |
2429 | LoopNode* CountedLoopNode::skip_strip_mined(int expect_skeleton) { |
2430 | if (is_strip_mined() && in(EntryControl) != NULL__null && in(EntryControl)->is_OuterStripMinedLoop()) { |
2431 | verify_strip_mined(expect_skeleton); |
2432 | return in(EntryControl)->as_Loop(); |
2433 | } |
2434 | return this; |
2435 | } |
2436 | |
2437 | OuterStripMinedLoopNode* CountedLoopNode::outer_loop() const { |
2438 | assert(is_strip_mined(), "not a strip mined loop")do { if (!(is_strip_mined())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2438, "assert(" "is_strip_mined()" ") failed", "not a strip mined loop" ); ::breakpoint(); } } while (0); |
2439 | Node* c = in(EntryControl); |
2440 | if (c == NULL__null || c->is_top() || !c->is_OuterStripMinedLoop()) { |
2441 | return NULL__null; |
2442 | } |
2443 | return c->as_OuterStripMinedLoop(); |
2444 | } |
2445 | |
2446 | IfTrueNode* OuterStripMinedLoopNode::outer_loop_tail() const { |
2447 | Node* c = in(LoopBackControl); |
2448 | if (c == NULL__null || c->is_top()) { |
2449 | return NULL__null; |
2450 | } |
2451 | return c->as_IfTrue(); |
2452 | } |
2453 | |
2454 | IfTrueNode* CountedLoopNode::outer_loop_tail() const { |
2455 | LoopNode* l = outer_loop(); |
2456 | if (l == NULL__null) { |
2457 | return NULL__null; |
2458 | } |
2459 | return l->outer_loop_tail(); |
2460 | } |
2461 | |
2462 | OuterStripMinedLoopEndNode* OuterStripMinedLoopNode::outer_loop_end() const { |
2463 | IfTrueNode* proj = outer_loop_tail(); |
2464 | if (proj == NULL__null) { |
2465 | return NULL__null; |
2466 | } |
2467 | Node* c = proj->in(0); |
2468 | if (c == NULL__null || c->is_top() || c->outcnt() != 2) { |
2469 | return NULL__null; |
2470 | } |
2471 | return c->as_OuterStripMinedLoopEnd(); |
2472 | } |
2473 | |
2474 | OuterStripMinedLoopEndNode* CountedLoopNode::outer_loop_end() const { |
2475 | LoopNode* l = outer_loop(); |
2476 | if (l == NULL__null) { |
2477 | return NULL__null; |
2478 | } |
2479 | return l->outer_loop_end(); |
2480 | } |
2481 | |
2482 | IfFalseNode* OuterStripMinedLoopNode::outer_loop_exit() const { |
2483 | IfNode* le = outer_loop_end(); |
2484 | if (le == NULL__null) { |
2485 | return NULL__null; |
2486 | } |
2487 | Node* c = le->proj_out_or_null(false); |
2488 | if (c == NULL__null) { |
2489 | return NULL__null; |
2490 | } |
2491 | return c->as_IfFalse(); |
2492 | } |
2493 | |
2494 | IfFalseNode* CountedLoopNode::outer_loop_exit() const { |
2495 | LoopNode* l = outer_loop(); |
2496 | if (l == NULL__null) { |
2497 | return NULL__null; |
2498 | } |
2499 | return l->outer_loop_exit(); |
2500 | } |
2501 | |
2502 | SafePointNode* OuterStripMinedLoopNode::outer_safepoint() const { |
2503 | IfNode* le = outer_loop_end(); |
2504 | if (le == NULL__null) { |
2505 | return NULL__null; |
2506 | } |
2507 | Node* c = le->in(0); |
2508 | if (c == NULL__null || c->is_top()) { |
2509 | return NULL__null; |
2510 | } |
2511 | assert(c->Opcode() == Op_SafePoint, "broken outer loop")do { if (!(c->Opcode() == Op_SafePoint)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2511, "assert(" "c->Opcode() == Op_SafePoint" ") failed" , "broken outer loop"); ::breakpoint(); } } while (0); |
2512 | return c->as_SafePoint(); |
2513 | } |
2514 | |
2515 | SafePointNode* CountedLoopNode::outer_safepoint() const { |
2516 | LoopNode* l = outer_loop(); |
2517 | if (l == NULL__null) { |
2518 | return NULL__null; |
2519 | } |
2520 | return l->outer_safepoint(); |
2521 | } |
2522 | |
2523 | Node* CountedLoopNode::skip_predicates_from_entry(Node* ctrl) { |
2524 | while (ctrl != NULL__null && ctrl->is_Proj() && ctrl->in(0) != NULL__null && ctrl->in(0)->is_If() && |
2525 | (ctrl->in(0)->as_If()->proj_out_or_null(1-ctrl->as_Proj()->_con) == NULL__null || |
2526 | (ctrl->in(0)->as_If()->proj_out(1-ctrl->as_Proj()->_con)->outcnt() == 1 && |
2527 | ctrl->in(0)->as_If()->proj_out(1-ctrl->as_Proj()->_con)->unique_out()->Opcode() == Op_Halt))) { |
2528 | ctrl = ctrl->in(0)->in(0); |
2529 | } |
2530 | |
2531 | return ctrl; |
2532 | } |
2533 | |
2534 | Node* CountedLoopNode::skip_predicates() { |
2535 | Node* ctrl = in(LoopNode::EntryControl); |
2536 | if (is_main_loop()) { |
2537 | ctrl = skip_strip_mined()->in(LoopNode::EntryControl); |
2538 | } |
2539 | if (is_main_loop() || is_post_loop()) { |
2540 | return skip_predicates_from_entry(ctrl); |
2541 | } |
2542 | return ctrl; |
2543 | } |
2544 | |
2545 | |
2546 | int CountedLoopNode::stride_con() const { |
2547 | CountedLoopEndNode* cle = loopexit_or_null(); |
2548 | return cle != NULL__null ? cle->stride_con() : 0; |
2549 | } |
2550 | |
2551 | BaseCountedLoopNode* BaseCountedLoopNode::make(Node* entry, Node* backedge, BasicType bt) { |
2552 | if (bt == T_INT) { |
2553 | return new CountedLoopNode(entry, backedge); |
2554 | } |
2555 | assert(bt == T_LONG, "unsupported")do { if (!(bt == T_LONG)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2555, "assert(" "bt == T_LONG" ") failed", "unsupported"); :: breakpoint(); } } while (0); |
2556 | return new LongCountedLoopNode(entry, backedge); |
2557 | } |
2558 | |
2559 | |
2560 | void OuterStripMinedLoopNode::adjust_strip_mined_loop(PhaseIterGVN* igvn) { |
2561 | // Look for the outer & inner strip mined loop, reduce number of |
2562 | // iterations of the inner loop, set exit condition of outer loop, |
2563 | // construct required phi nodes for outer loop. |
2564 | CountedLoopNode* inner_cl = unique_ctrl_out()->as_CountedLoop(); |
2565 | assert(inner_cl->is_strip_mined(), "inner loop should be strip mined")do { if (!(inner_cl->is_strip_mined())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2565, "assert(" "inner_cl->is_strip_mined()" ") failed", "inner loop should be strip mined"); ::breakpoint(); } } while (0); |
2566 | Node* inner_iv_phi = inner_cl->phi(); |
2567 | if (inner_iv_phi == NULL__null) { |
2568 | IfNode* outer_le = outer_loop_end(); |
2569 | Node* iff = igvn->transform(new IfNode(outer_le->in(0), outer_le->in(1), outer_le->_prob, outer_le->_fcnt)); |
2570 | igvn->replace_node(outer_le, iff); |
2571 | inner_cl->clear_strip_mined(); |
2572 | return; |
2573 | } |
2574 | CountedLoopEndNode* inner_cle = inner_cl->loopexit(); |
2575 | |
2576 | int stride = inner_cl->stride_con(); |
2577 | jlong scaled_iters_long = ((jlong)LoopStripMiningIter) * ABS(stride); |
2578 | int scaled_iters = (int)scaled_iters_long; |
2579 | int short_scaled_iters = LoopStripMiningIterShortLoop* ABS(stride); |
2580 | const TypeInt* inner_iv_t = igvn->type(inner_iv_phi)->is_int(); |
2581 | jlong iter_estimate = (jlong)inner_iv_t->_hi - (jlong)inner_iv_t->_lo; |
2582 | assert(iter_estimate > 0, "broken")do { if (!(iter_estimate > 0)) { (*g_assert_poison) = 'X'; ; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2582, "assert(" "iter_estimate > 0" ") failed", "broken" ); ::breakpoint(); } } while (0); |
2583 | if ((jlong)scaled_iters != scaled_iters_long || iter_estimate <= short_scaled_iters) { |
2584 | // Remove outer loop and safepoint (too few iterations) |
2585 | Node* outer_sfpt = outer_safepoint(); |
2586 | Node* outer_out = outer_loop_exit(); |
2587 | igvn->replace_node(outer_out, outer_sfpt->in(0)); |
2588 | igvn->replace_input_of(outer_sfpt, 0, igvn->C->top()); |
2589 | inner_cl->clear_strip_mined(); |
2590 | return; |
2591 | } |
2592 | if (iter_estimate <= scaled_iters_long) { |
2593 | // We would only go through one iteration of |
2594 | // the outer loop: drop the outer loop but |
2595 | // keep the safepoint so we don't run for |
2596 | // too long without a safepoint |
2597 | IfNode* outer_le = outer_loop_end(); |
2598 | Node* iff = igvn->transform(new IfNode(outer_le->in(0), outer_le->in(1), outer_le->_prob, outer_le->_fcnt)); |
2599 | igvn->replace_node(outer_le, iff); |
2600 | inner_cl->clear_strip_mined(); |
2601 | return; |
2602 | } |
2603 | |
2604 | Node* cle_tail = inner_cle->proj_out(true); |
2605 | ResourceMark rm; |
2606 | Node_List old_new; |
2607 | if (cle_tail->outcnt() > 1) { |
2608 | // Look for nodes on backedge of inner loop and clone them |
2609 | Unique_Node_List backedge_nodes; |
2610 | for (DUIterator_Fast imax, i = cle_tail->fast_outs(imax); i < imax; i++) { |
2611 | Node* u = cle_tail->fast_out(i); |
2612 | if (u != inner_cl) { |
2613 | assert(!u->is_CFG(), "control flow on the backedge?")do { if (!(!u->is_CFG())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2613, "assert(" "!u->is_CFG()" ") failed", "control flow on the backedge?" ); ::breakpoint(); } } while (0); |
2614 | backedge_nodes.push(u); |
2615 | } |
2616 | } |
2617 | uint last = igvn->C->unique(); |
2618 | for (uint next = 0; next < backedge_nodes.size(); next++) { |
2619 | Node* n = backedge_nodes.at(next); |
2620 | old_new.map(n->_idx, n->clone()); |
2621 | for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { |
2622 | Node* u = n->fast_out(i); |
2623 | assert(!u->is_CFG(), "broken")do { if (!(!u->is_CFG())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2623, "assert(" "!u->is_CFG()" ") failed", "broken"); :: breakpoint(); } } while (0); |
2624 | if (u->_idx >= last) { |
2625 | continue; |
2626 | } |
2627 | if (!u->is_Phi()) { |
2628 | backedge_nodes.push(u); |
2629 | } else { |
2630 | assert(u->in(0) == inner_cl, "strange phi on the backedge")do { if (!(u->in(0) == inner_cl)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2630, "assert(" "u->in(0) == inner_cl" ") failed", "strange phi on the backedge" ); ::breakpoint(); } } while (0); |
2631 | } |
2632 | } |
2633 | } |
2634 | // Put the clones on the outer loop backedge |
2635 | Node* le_tail = outer_loop_tail(); |
2636 | for (uint next = 0; next < backedge_nodes.size(); next++) { |
2637 | Node *n = old_new[backedge_nodes.at(next)->_idx]; |
2638 | for (uint i = 1; i < n->req(); i++) { |
2639 | if (n->in(i) != NULL__null && old_new[n->in(i)->_idx] != NULL__null) { |
2640 | n->set_req(i, old_new[n->in(i)->_idx]); |
2641 | } |
2642 | } |
2643 | if (n->in(0) != NULL__null && n->in(0) == cle_tail) { |
2644 | n->set_req(0, le_tail); |
2645 | } |
2646 | igvn->register_new_node_with_optimizer(n); |
2647 | } |
2648 | } |
2649 | |
2650 | Node* iv_phi = NULL__null; |
2651 | // Make a clone of each phi in the inner loop |
2652 | // for the outer loop |
2653 | for (uint i = 0; i < inner_cl->outcnt(); i++) { |
2654 | Node* u = inner_cl->raw_out(i); |
2655 | if (u->is_Phi()) { |
2656 | assert(u->in(0) == inner_cl, "inconsistent")do { if (!(u->in(0) == inner_cl)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2656, "assert(" "u->in(0) == inner_cl" ") failed", "inconsistent" ); ::breakpoint(); } } while (0); |
2657 | Node* phi = u->clone(); |
2658 | phi->set_req(0, this); |
2659 | Node* be = old_new[phi->in(LoopNode::LoopBackControl)->_idx]; |
2660 | if (be != NULL__null) { |
2661 | phi->set_req(LoopNode::LoopBackControl, be); |
2662 | } |
2663 | phi = igvn->transform(phi); |
2664 | igvn->replace_input_of(u, LoopNode::EntryControl, phi); |
2665 | if (u == inner_iv_phi) { |
2666 | iv_phi = phi; |
2667 | } |
2668 | } |
2669 | } |
2670 | Node* cle_out = inner_cle->proj_out(false); |
2671 | if (cle_out->outcnt() > 1) { |
2672 | // Look for chains of stores that were sunk |
2673 | // out of the inner loop and are in the outer loop |
2674 | for (DUIterator_Fast imax, i = cle_out->fast_outs(imax); i < imax; i++) { |
2675 | Node* u = cle_out->fast_out(i); |
2676 | if (u->is_Store()) { |
2677 | Node* first = u; |
2678 | for(;;) { |
2679 | Node* next = first->in(MemNode::Memory); |
2680 | if (!next->is_Store() || next->in(0) != cle_out) { |
2681 | break; |
2682 | } |
2683 | first = next; |
2684 | } |
2685 | Node* last = u; |
2686 | for(;;) { |
2687 | Node* next = NULL__null; |
2688 | for (DUIterator_Fast jmax, j = last->fast_outs(jmax); j < jmax; j++) { |
2689 | Node* uu = last->fast_out(j); |
2690 | if (uu->is_Store() && uu->in(0) == cle_out) { |
2691 | assert(next == NULL, "only one in the outer loop")do { if (!(next == __null)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2691, "assert(" "next == __null" ") failed", "only one in the outer loop" ); ::breakpoint(); } } while (0); |
2692 | next = uu; |
2693 | } |
2694 | } |
2695 | if (next == NULL__null) { |
2696 | break; |
2697 | } |
2698 | last = next; |
2699 | } |
2700 | Node* phi = NULL__null; |
2701 | for (DUIterator_Fast jmax, j = fast_outs(jmax); j < jmax; j++) { |
2702 | Node* uu = fast_out(j); |
2703 | if (uu->is_Phi()) { |
2704 | Node* be = uu->in(LoopNode::LoopBackControl); |
2705 | if (be->is_Store() && old_new[be->_idx] != NULL__null) { |
2706 | assert(false, "store on the backedge + sunk stores: unsupported")do { if (!(false)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2706, "assert(" "false" ") failed", "store on the backedge + sunk stores: unsupported" ); ::breakpoint(); } } while (0); |
2707 | // drop outer loop |
2708 | IfNode* outer_le = outer_loop_end(); |
2709 | Node* iff = igvn->transform(new IfNode(outer_le->in(0), outer_le->in(1), outer_le->_prob, outer_le->_fcnt)); |
2710 | igvn->replace_node(outer_le, iff); |
2711 | inner_cl->clear_strip_mined(); |
2712 | return; |
2713 | } |
2714 | if (be == last || be == first->in(MemNode::Memory)) { |
2715 | assert(phi == NULL, "only one phi")do { if (!(phi == __null)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2715, "assert(" "phi == __null" ") failed", "only one phi") ; ::breakpoint(); } } while (0); |
2716 | phi = uu; |
2717 | } |
2718 | } |
2719 | } |
2720 | #ifdef ASSERT1 |
2721 | for (DUIterator_Fast jmax, j = fast_outs(jmax); j < jmax; j++) { |
2722 | Node* uu = fast_out(j); |
2723 | if (uu->is_Phi() && uu->bottom_type() == Type::MEMORY) { |
2724 | if (uu->adr_type() == igvn->C->get_adr_type(igvn->C->get_alias_index(u->adr_type()))) { |
2725 | assert(phi == uu, "what's that phi?")do { if (!(phi == uu)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2725, "assert(" "phi == uu" ") failed", "what's that phi?") ; ::breakpoint(); } } while (0); |
2726 | } else if (uu->adr_type() == TypePtr::BOTTOM) { |
2727 | Node* n = uu->in(LoopNode::LoopBackControl); |
2728 | uint limit = igvn->C->live_nodes(); |
2729 | uint i = 0; |
2730 | while (n != uu) { |
2731 | i++; |
2732 | assert(i < limit, "infinite loop")do { if (!(i < limit)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2732, "assert(" "i < limit" ") failed", "infinite loop") ; ::breakpoint(); } } while (0); |
2733 | if (n->is_Proj()) { |
2734 | n = n->in(0); |
2735 | } else if (n->is_SafePoint() || n->is_MemBar()) { |
2736 | n = n->in(TypeFunc::Memory); |
2737 | } else if (n->is_Phi()) { |
2738 | n = n->in(1); |
2739 | } else if (n->is_MergeMem()) { |
2740 | n = n->as_MergeMem()->memory_at(igvn->C->get_alias_index(u->adr_type())); |
2741 | } else if (n->is_Store() || n->is_LoadStore() || n->is_ClearArray()) { |
2742 | n = n->in(MemNode::Memory); |
2743 | } else { |
2744 | n->dump(); |
2745 | ShouldNotReachHere()do { (*g_assert_poison) = 'X';; report_should_not_reach_here( "/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2745); ::breakpoint(); } while (0); |
2746 | } |
2747 | } |
2748 | } |
2749 | } |
2750 | } |
2751 | #endif |
2752 | if (phi == NULL__null) { |
2753 | // If the an entire chains was sunk, the |
2754 | // inner loop has no phi for that memory |
2755 | // slice, create one for the outer loop |
2756 | phi = PhiNode::make(this, first->in(MemNode::Memory), Type::MEMORY, |
2757 | igvn->C->get_adr_type(igvn->C->get_alias_index(u->adr_type()))); |
2758 | phi->set_req(LoopNode::LoopBackControl, last); |
2759 | phi = igvn->transform(phi); |
2760 | igvn->replace_input_of(first, MemNode::Memory, phi); |
2761 | } else { |
2762 | // Or fix the outer loop fix to include |
2763 | // that chain of stores. |
2764 | Node* be = phi->in(LoopNode::LoopBackControl); |
2765 | assert(!(be->is_Store() && old_new[be->_idx] != NULL), "store on the backedge + sunk stores: unsupported")do { if (!(!(be->is_Store() && old_new[be->_idx ] != __null))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2765, "assert(" "!(be->is_Store() && old_new[be->_idx] != __null)" ") failed", "store on the backedge + sunk stores: unsupported" ); ::breakpoint(); } } while (0); |
2766 | if (be == first->in(MemNode::Memory)) { |
2767 | if (be == phi->in(LoopNode::LoopBackControl)) { |
2768 | igvn->replace_input_of(phi, LoopNode::LoopBackControl, last); |
2769 | } else { |
2770 | igvn->replace_input_of(be, MemNode::Memory, last); |
2771 | } |
2772 | } else { |
2773 | #ifdef ASSERT1 |
2774 | if (be == phi->in(LoopNode::LoopBackControl)) { |
2775 | assert(phi->in(LoopNode::LoopBackControl) == last, "")do { if (!(phi->in(LoopNode::LoopBackControl) == last)) { ( *g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2775, "assert(" "phi->in(LoopNode::LoopBackControl) == last" ") failed", ""); ::breakpoint(); } } while (0); |
2776 | } else { |
2777 | assert(be->in(MemNode::Memory) == last, "")do { if (!(be->in(MemNode::Memory) == last)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2777, "assert(" "be->in(MemNode::Memory) == last" ") failed" , ""); ::breakpoint(); } } while (0); |
2778 | } |
2779 | #endif |
2780 | } |
2781 | } |
2782 | } |
2783 | } |
2784 | } |
2785 | |
2786 | if (iv_phi != NULL__null) { |
2787 | // Now adjust the inner loop's exit condition |
2788 | Node* limit = inner_cl->limit(); |
2789 | // If limit < init for stride > 0 (or limit > init for stride < 0), |
2790 | // the loop body is run only once. Given limit - init (init - limit resp.) |
2791 | // would be negative, the unsigned comparison below would cause |
2792 | // the loop body to be run for LoopStripMiningIter. |
2793 | Node* max = NULL__null; |
2794 | if (stride > 0) { |
2795 | max = MaxNode::max_diff_with_zero(limit, iv_phi, TypeInt::INT, *igvn); |
2796 | } else { |
2797 | max = MaxNode::max_diff_with_zero(iv_phi, limit, TypeInt::INT, *igvn); |
2798 | } |
2799 | // sub is positive and can be larger than the max signed int |
2800 | // value. Use an unsigned min. |
2801 | Node* const_iters = igvn->intcon(scaled_iters); |
2802 | Node* min = MaxNode::unsigned_min(max, const_iters, TypeInt::make(0, scaled_iters, Type::WidenMin), *igvn); |
2803 | // min is the number of iterations for the next inner loop execution: |
2804 | // unsigned_min(max(limit - iv_phi, 0), scaled_iters) if stride > 0 |
2805 | // unsigned_min(max(iv_phi - limit, 0), scaled_iters) if stride < 0 |
2806 | |
2807 | Node* new_limit = NULL__null; |
2808 | if (stride > 0) { |
2809 | new_limit = igvn->transform(new AddINode(min, iv_phi)); |
2810 | } else { |
2811 | new_limit = igvn->transform(new SubINode(iv_phi, min)); |
2812 | } |
2813 | Node* inner_cmp = inner_cle->cmp_node(); |
2814 | Node* inner_bol = inner_cle->in(CountedLoopEndNode::TestValue); |
2815 | Node* outer_bol = inner_bol; |
2816 | // cmp node for inner loop may be shared |
2817 | inner_cmp = inner_cmp->clone(); |
2818 | inner_cmp->set_req(2, new_limit); |
2819 | inner_bol = inner_bol->clone(); |
2820 | inner_bol->set_req(1, igvn->transform(inner_cmp)); |
2821 | igvn->replace_input_of(inner_cle, CountedLoopEndNode::TestValue, igvn->transform(inner_bol)); |
2822 | // Set the outer loop's exit condition too |
2823 | igvn->replace_input_of(outer_loop_end(), 1, outer_bol); |
2824 | } else { |
2825 | assert(false, "should be able to adjust outer loop")do { if (!(false)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2825, "assert(" "false" ") failed", "should be able to adjust outer loop" ); ::breakpoint(); } } while (0); |
2826 | IfNode* outer_le = outer_loop_end(); |
2827 | Node* iff = igvn->transform(new IfNode(outer_le->in(0), outer_le->in(1), outer_le->_prob, outer_le->_fcnt)); |
2828 | igvn->replace_node(outer_le, iff); |
2829 | inner_cl->clear_strip_mined(); |
2830 | } |
2831 | } |
2832 | |
2833 | const Type* OuterStripMinedLoopEndNode::Value(PhaseGVN* phase) const { |
2834 | if (!in(0)) return Type::TOP; |
2835 | if (phase->type(in(0)) == Type::TOP) |
2836 | return Type::TOP; |
2837 | |
2838 | // Until expansion, the loop end condition is not set so this should not constant fold. |
2839 | if (is_expanded(phase)) { |
2840 | return IfNode::Value(phase); |
2841 | } |
2842 | |
2843 | return TypeTuple::IFBOTH; |
2844 | } |
2845 | |
2846 | bool OuterStripMinedLoopEndNode::is_expanded(PhaseGVN *phase) const { |
2847 | // The outer strip mined loop head only has Phi uses after expansion |
2848 | if (phase->is_IterGVN()) { |
2849 | Node* backedge = proj_out_or_null(true); |
2850 | if (backedge != NULL__null) { |
2851 | Node* head = backedge->unique_ctrl_out(); |
2852 | if (head != NULL__null && head->is_OuterStripMinedLoop()) { |
2853 | if (head->find_out_with(Op_Phi) != NULL__null) { |
2854 | return true; |
2855 | } |
2856 | } |
2857 | } |
2858 | } |
2859 | return false; |
2860 | } |
2861 | |
2862 | Node *OuterStripMinedLoopEndNode::Ideal(PhaseGVN *phase, bool can_reshape) { |
2863 | if (remove_dead_region(phase, can_reshape)) return this; |
2864 | |
2865 | return NULL__null; |
2866 | } |
2867 | |
2868 | //------------------------------filtered_type-------------------------------- |
2869 | // Return a type based on condition control flow |
2870 | // A successful return will be a type that is restricted due |
2871 | // to a series of dominating if-tests, such as: |
2872 | // if (i < 10) { |
2873 | // if (i > 0) { |
2874 | // here: "i" type is [1..10) |
2875 | // } |
2876 | // } |
2877 | // or a control flow merge |
2878 | // if (i < 10) { |
2879 | // do { |
2880 | // phi( , ) -- at top of loop type is [min_int..10) |
2881 | // i = ? |
2882 | // } while ( i < 10) |
2883 | // |
2884 | const TypeInt* PhaseIdealLoop::filtered_type( Node *n, Node* n_ctrl) { |
2885 | assert(n && n->bottom_type()->is_int(), "must be int")do { if (!(n && n->bottom_type()->is_int())) { ( *g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2885, "assert(" "n && n->bottom_type()->is_int()" ") failed", "must be int"); ::breakpoint(); } } while (0); |
2886 | const TypeInt* filtered_t = NULL__null; |
2887 | if (!n->is_Phi()) { |
2888 | assert(n_ctrl != NULL || n_ctrl == C->top(), "valid control")do { if (!(n_ctrl != __null || n_ctrl == C->top())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2888, "assert(" "n_ctrl != __null || n_ctrl == C->top()" ") failed", "valid control"); ::breakpoint(); } } while (0); |
2889 | filtered_t = filtered_type_from_dominators(n, n_ctrl); |
2890 | |
2891 | } else { |
2892 | Node* phi = n->as_Phi(); |
2893 | Node* region = phi->in(0); |
2894 | assert(n_ctrl == NULL || n_ctrl == region, "ctrl parameter must be region")do { if (!(n_ctrl == __null || n_ctrl == region)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2894, "assert(" "n_ctrl == __null || n_ctrl == region" ") failed" , "ctrl parameter must be region"); ::breakpoint(); } } while (0); |
2895 | if (region && region != C->top()) { |
2896 | for (uint i = 1; i < phi->req(); i++) { |
2897 | Node* val = phi->in(i); |
2898 | Node* use_c = region->in(i); |
2899 | const TypeInt* val_t = filtered_type_from_dominators(val, use_c); |
2900 | if (val_t != NULL__null) { |
2901 | if (filtered_t == NULL__null) { |
2902 | filtered_t = val_t; |
2903 | } else { |
2904 | filtered_t = filtered_t->meet(val_t)->is_int(); |
2905 | } |
2906 | } |
2907 | } |
2908 | } |
2909 | } |
2910 | const TypeInt* n_t = _igvn.type(n)->is_int(); |
2911 | if (filtered_t != NULL__null) { |
2912 | n_t = n_t->join(filtered_t)->is_int(); |
2913 | } |
2914 | return n_t; |
2915 | } |
2916 | |
2917 | |
2918 | //------------------------------filtered_type_from_dominators-------------------------------- |
2919 | // Return a possibly more restrictive type for val based on condition control flow of dominators |
2920 | const TypeInt* PhaseIdealLoop::filtered_type_from_dominators( Node* val, Node *use_ctrl) { |
2921 | if (val->is_Con()) { |
2922 | return val->bottom_type()->is_int(); |
2923 | } |
2924 | uint if_limit = 10; // Max number of dominating if's visited |
2925 | const TypeInt* rtn_t = NULL__null; |
2926 | |
2927 | if (use_ctrl && use_ctrl != C->top()) { |
2928 | Node* val_ctrl = get_ctrl(val); |
2929 | uint val_dom_depth = dom_depth(val_ctrl); |
2930 | Node* pred = use_ctrl; |
2931 | uint if_cnt = 0; |
2932 | while (if_cnt < if_limit) { |
2933 | if ((pred->Opcode() == Op_IfTrue || pred->Opcode() == Op_IfFalse)) { |
2934 | if_cnt++; |
2935 | const TypeInt* if_t = IfNode::filtered_int_type(&_igvn, val, pred); |
2936 | if (if_t != NULL__null) { |
2937 | if (rtn_t == NULL__null) { |
2938 | rtn_t = if_t; |
2939 | } else { |
2940 | rtn_t = rtn_t->join(if_t)->is_int(); |
2941 | } |
2942 | } |
2943 | } |
2944 | pred = idom(pred); |
2945 | if (pred == NULL__null || pred == C->top()) { |
2946 | break; |
2947 | } |
2948 | // Stop if going beyond definition block of val |
2949 | if (dom_depth(pred) < val_dom_depth) { |
2950 | break; |
2951 | } |
2952 | } |
2953 | } |
2954 | return rtn_t; |
2955 | } |
2956 | |
2957 | |
2958 | //------------------------------dump_spec-------------------------------------- |
2959 | // Dump special per-node info |
2960 | #ifndef PRODUCT |
2961 | void CountedLoopEndNode::dump_spec(outputStream *st) const { |
2962 | if( in(TestValue) != NULL__null && in(TestValue)->is_Bool() ) { |
2963 | BoolTest bt( test_trip()); // Added this for g++. |
2964 | |
2965 | st->print("["); |
2966 | bt.dump_on(st); |
2967 | st->print("]"); |
2968 | } |
2969 | st->print(" "); |
2970 | IfNode::dump_spec(st); |
2971 | } |
2972 | #endif |
2973 | |
2974 | //============================================================================= |
2975 | //------------------------------is_member-------------------------------------- |
2976 | // Is 'l' a member of 'this'? |
2977 | bool IdealLoopTree::is_member(const IdealLoopTree *l) const { |
2978 | while( l->_nest > _nest ) l = l->_parent; |
2979 | return l == this; |
2980 | } |
2981 | |
2982 | //------------------------------set_nest--------------------------------------- |
2983 | // Set loop tree nesting depth. Accumulate _has_call bits. |
2984 | int IdealLoopTree::set_nest( uint depth ) { |
2985 | assert(depth <= SHRT_MAX, "sanity")do { if (!(depth <= 32767)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 2985, "assert(" "depth <= 32767" ") failed", "sanity"); :: breakpoint(); } } while (0); |
2986 | _nest = depth; |
2987 | int bits = _has_call; |
2988 | if( _child ) bits |= _child->set_nest(depth+1); |
2989 | if( bits ) _has_call = 1; |
2990 | if( _next ) bits |= _next ->set_nest(depth ); |
2991 | return bits; |
2992 | } |
2993 | |
2994 | //------------------------------split_fall_in---------------------------------- |
2995 | // Split out multiple fall-in edges from the loop header. Move them to a |
2996 | // private RegionNode before the loop. This becomes the loop landing pad. |
2997 | void IdealLoopTree::split_fall_in( PhaseIdealLoop *phase, int fall_in_cnt ) { |
2998 | PhaseIterGVN &igvn = phase->_igvn; |
2999 | uint i; |
3000 | |
3001 | // Make a new RegionNode to be the landing pad. |
3002 | Node *landing_pad = new RegionNode( fall_in_cnt+1 ); |
3003 | phase->set_loop(landing_pad,_parent); |
3004 | // Gather all the fall-in control paths into the landing pad |
3005 | uint icnt = fall_in_cnt; |
3006 | uint oreq = _head->req(); |
3007 | for( i = oreq-1; i>0; i-- ) |
3008 | if( !phase->is_member( this, _head->in(i) ) ) |
3009 | landing_pad->set_req(icnt--,_head->in(i)); |
3010 | |
3011 | // Peel off PhiNode edges as well |
3012 | for (DUIterator_Fast jmax, j = _head->fast_outs(jmax); j < jmax; j++) { |
3013 | Node *oj = _head->fast_out(j); |
3014 | if( oj->is_Phi() ) { |
3015 | PhiNode* old_phi = oj->as_Phi(); |
3016 | assert( old_phi->region() == _head, "" )do { if (!(old_phi->region() == _head)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3016, "assert(" "old_phi->region() == _head" ") failed", ""); ::breakpoint(); } } while (0); |
3017 | igvn.hash_delete(old_phi); // Yank from hash before hacking edges |
3018 | Node *p = PhiNode::make_blank(landing_pad, old_phi); |
3019 | uint icnt = fall_in_cnt; |
3020 | for( i = oreq-1; i>0; i-- ) { |
3021 | if( !phase->is_member( this, _head->in(i) ) ) { |
3022 | p->init_req(icnt--, old_phi->in(i)); |
3023 | // Go ahead and clean out old edges from old phi |
3024 | old_phi->del_req(i); |
3025 | } |
3026 | } |
3027 | // Search for CSE's here, because ZKM.jar does a lot of |
3028 | // loop hackery and we need to be a little incremental |
3029 | // with the CSE to avoid O(N^2) node blow-up. |
3030 | Node *p2 = igvn.hash_find_insert(p); // Look for a CSE |
3031 | if( p2 ) { // Found CSE |
3032 | p->destruct(&igvn); // Recover useless new node |
3033 | p = p2; // Use old node |
3034 | } else { |
3035 | igvn.register_new_node_with_optimizer(p, old_phi); |
3036 | } |
3037 | // Make old Phi refer to new Phi. |
3038 | old_phi->add_req(p); |
3039 | // Check for the special case of making the old phi useless and |
3040 | // disappear it. In JavaGrande I have a case where this useless |
3041 | // Phi is the loop limit and prevents recognizing a CountedLoop |
3042 | // which in turn prevents removing an empty loop. |
3043 | Node *id_old_phi = old_phi->Identity(&igvn); |
3044 | if( id_old_phi != old_phi ) { // Found a simple identity? |
3045 | // Note that I cannot call 'replace_node' here, because |
3046 | // that will yank the edge from old_phi to the Region and |
3047 | // I'm mid-iteration over the Region's uses. |
3048 | for (DUIterator_Last imin, i = old_phi->last_outs(imin); i >= imin; ) { |
3049 | Node* use = old_phi->last_out(i); |
3050 | igvn.rehash_node_delayed(use); |
3051 | uint uses_found = 0; |
3052 | for (uint j = 0; j < use->len(); j++) { |
3053 | if (use->in(j) == old_phi) { |
3054 | if (j < use->req()) use->set_req (j, id_old_phi); |
3055 | else use->set_prec(j, id_old_phi); |
3056 | uses_found++; |
3057 | } |
3058 | } |
3059 | i -= uses_found; // we deleted 1 or more copies of this edge |
3060 | } |
3061 | } |
3062 | igvn._worklist.push(old_phi); |
3063 | } |
3064 | } |
3065 | // Finally clean out the fall-in edges from the RegionNode |
3066 | for( i = oreq-1; i>0; i-- ) { |
3067 | if( !phase->is_member( this, _head->in(i) ) ) { |
3068 | _head->del_req(i); |
3069 | } |
3070 | } |
3071 | igvn.rehash_node_delayed(_head); |
3072 | // Transform landing pad |
3073 | igvn.register_new_node_with_optimizer(landing_pad, _head); |
3074 | // Insert landing pad into the header |
3075 | _head->add_req(landing_pad); |
3076 | } |
3077 | |
3078 | //------------------------------split_outer_loop------------------------------- |
3079 | // Split out the outermost loop from this shared header. |
3080 | void IdealLoopTree::split_outer_loop( PhaseIdealLoop *phase ) { |
3081 | PhaseIterGVN &igvn = phase->_igvn; |
3082 | |
3083 | // Find index of outermost loop; it should also be my tail. |
3084 | uint outer_idx = 1; |
3085 | while( _head->in(outer_idx) != _tail ) outer_idx++; |
3086 | |
3087 | // Make a LoopNode for the outermost loop. |
3088 | Node *ctl = _head->in(LoopNode::EntryControl); |
3089 | Node *outer = new LoopNode( ctl, _head->in(outer_idx) ); |
3090 | outer = igvn.register_new_node_with_optimizer(outer, _head); |
3091 | phase->set_created_loop_node(); |
3092 | |
3093 | // Outermost loop falls into '_head' loop |
3094 | _head->set_req(LoopNode::EntryControl, outer); |
3095 | _head->del_req(outer_idx); |
3096 | // Split all the Phis up between '_head' loop and 'outer' loop. |
3097 | for (DUIterator_Fast jmax, j = _head->fast_outs(jmax); j < jmax; j++) { |
3098 | Node *out = _head->fast_out(j); |
3099 | if( out->is_Phi() ) { |
3100 | PhiNode *old_phi = out->as_Phi(); |
3101 | assert( old_phi->region() == _head, "" )do { if (!(old_phi->region() == _head)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3101, "assert(" "old_phi->region() == _head" ") failed", ""); ::breakpoint(); } } while (0); |
3102 | Node *phi = PhiNode::make_blank(outer, old_phi); |
3103 | phi->init_req(LoopNode::EntryControl, old_phi->in(LoopNode::EntryControl)); |
3104 | phi->init_req(LoopNode::LoopBackControl, old_phi->in(outer_idx)); |
3105 | phi = igvn.register_new_node_with_optimizer(phi, old_phi); |
3106 | // Make old Phi point to new Phi on the fall-in path |
3107 | igvn.replace_input_of(old_phi, LoopNode::EntryControl, phi); |
3108 | old_phi->del_req(outer_idx); |
3109 | } |
3110 | } |
3111 | |
3112 | // Use the new loop head instead of the old shared one |
3113 | _head = outer; |
3114 | phase->set_loop(_head, this); |
3115 | } |
3116 | |
3117 | //------------------------------fix_parent------------------------------------- |
3118 | static void fix_parent( IdealLoopTree *loop, IdealLoopTree *parent ) { |
3119 | loop->_parent = parent; |
3120 | if( loop->_child ) fix_parent( loop->_child, loop ); |
3121 | if( loop->_next ) fix_parent( loop->_next , parent ); |
3122 | } |
3123 | |
3124 | //------------------------------estimate_path_freq----------------------------- |
3125 | static float estimate_path_freq( Node *n ) { |
3126 | // Try to extract some path frequency info |
3127 | IfNode *iff; |
3128 | for( int i = 0; i < 50; i++ ) { // Skip through a bunch of uncommon tests |
3129 | uint nop = n->Opcode(); |
3130 | if( nop == Op_SafePoint ) { // Skip any safepoint |
3131 | n = n->in(0); |
3132 | continue; |
3133 | } |
3134 | if( nop == Op_CatchProj ) { // Get count from a prior call |
3135 | // Assume call does not always throw exceptions: means the call-site |
3136 | // count is also the frequency of the fall-through path. |
3137 | assert( n->is_CatchProj(), "" )do { if (!(n->is_CatchProj())) { (*g_assert_poison) = 'X'; ; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3137, "assert(" "n->is_CatchProj()" ") failed", ""); ::breakpoint (); } } while (0); |
3138 | if( ((CatchProjNode*)n)->_con != CatchProjNode::fall_through_index ) |
3139 | return 0.0f; // Assume call exception path is rare |
3140 | Node *call = n->in(0)->in(0)->in(0); |
3141 | assert( call->is_Call(), "expect a call here" )do { if (!(call->is_Call())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3141, "assert(" "call->is_Call()" ") failed", "expect a call here" ); ::breakpoint(); } } while (0); |
3142 | const JVMState *jvms = ((CallNode*)call)->jvms(); |
3143 | ciMethodData* methodData = jvms->method()->method_data(); |
3144 | if (!methodData->is_mature()) return 0.0f; // No call-site data |
3145 | ciProfileData* data = methodData->bci_to_data(jvms->bci()); |
3146 | if ((data == NULL__null) || !data->is_CounterData()) { |
3147 | // no call profile available, try call's control input |
3148 | n = n->in(0); |
3149 | continue; |
3150 | } |
3151 | return data->as_CounterData()->count()/FreqCountInvocations; |
3152 | } |
3153 | // See if there's a gating IF test |
3154 | Node *n_c = n->in(0); |
3155 | if( !n_c->is_If() ) break; // No estimate available |
3156 | iff = n_c->as_If(); |
3157 | if( iff->_fcnt != COUNT_UNKNOWN(-1.0f) ) // Have a valid count? |
3158 | // Compute how much count comes on this path |
3159 | return ((nop == Op_IfTrue) ? iff->_prob : 1.0f - iff->_prob) * iff->_fcnt; |
3160 | // Have no count info. Skip dull uncommon-trap like branches. |
3161 | if( (nop == Op_IfTrue && iff->_prob < PROB_LIKELY_MAG(5)(1.0f-(1e-5f))) || |
3162 | (nop == Op_IfFalse && iff->_prob > PROB_UNLIKELY_MAG(5)(1e-5f)) ) |
3163 | break; |
3164 | // Skip through never-taken branch; look for a real loop exit. |
3165 | n = iff->in(0); |
3166 | } |
3167 | return 0.0f; // No estimate available |
3168 | } |
3169 | |
3170 | //------------------------------merge_many_backedges--------------------------- |
3171 | // Merge all the backedges from the shared header into a private Region. |
3172 | // Feed that region as the one backedge to this loop. |
3173 | void IdealLoopTree::merge_many_backedges( PhaseIdealLoop *phase ) { |
3174 | uint i; |
3175 | |
3176 | // Scan for the top 2 hottest backedges |
3177 | float hotcnt = 0.0f; |
3178 | float warmcnt = 0.0f; |
3179 | uint hot_idx = 0; |
3180 | // Loop starts at 2 because slot 1 is the fall-in path |
3181 | for( i = 2; i < _head->req(); i++ ) { |
3182 | float cnt = estimate_path_freq(_head->in(i)); |
3183 | if( cnt > hotcnt ) { // Grab hottest path |
3184 | warmcnt = hotcnt; |
3185 | hotcnt = cnt; |
3186 | hot_idx = i; |
3187 | } else if( cnt > warmcnt ) { // And 2nd hottest path |
3188 | warmcnt = cnt; |
3189 | } |
3190 | } |
3191 | |
3192 | // See if the hottest backedge is worthy of being an inner loop |
3193 | // by being much hotter than the next hottest backedge. |
3194 | if( hotcnt <= 0.0001 || |
3195 | hotcnt < 2.0*warmcnt ) hot_idx = 0;// No hot backedge |
3196 | |
3197 | // Peel out the backedges into a private merge point; peel |
3198 | // them all except optionally hot_idx. |
3199 | PhaseIterGVN &igvn = phase->_igvn; |
3200 | |
3201 | Node *hot_tail = NULL__null; |
3202 | // Make a Region for the merge point |
3203 | Node *r = new RegionNode(1); |
3204 | for( i = 2; i < _head->req(); i++ ) { |
3205 | if( i != hot_idx ) |
3206 | r->add_req( _head->in(i) ); |
3207 | else hot_tail = _head->in(i); |
3208 | } |
3209 | igvn.register_new_node_with_optimizer(r, _head); |
3210 | // Plug region into end of loop _head, followed by hot_tail |
3211 | while( _head->req() > 3 ) _head->del_req( _head->req()-1 ); |
3212 | igvn.replace_input_of(_head, 2, r); |
3213 | if( hot_idx ) _head->add_req(hot_tail); |
3214 | |
3215 | // Split all the Phis up between '_head' loop and the Region 'r' |
3216 | for (DUIterator_Fast jmax, j = _head->fast_outs(jmax); j < jmax; j++) { |
3217 | Node *out = _head->fast_out(j); |
3218 | if( out->is_Phi() ) { |
3219 | PhiNode* n = out->as_Phi(); |
3220 | igvn.hash_delete(n); // Delete from hash before hacking edges |
3221 | Node *hot_phi = NULL__null; |
3222 | Node *phi = new PhiNode(r, n->type(), n->adr_type()); |
3223 | // Check all inputs for the ones to peel out |
3224 | uint j = 1; |
3225 | for( uint i = 2; i < n->req(); i++ ) { |
3226 | if( i != hot_idx ) |
3227 | phi->set_req( j++, n->in(i) ); |
3228 | else hot_phi = n->in(i); |
3229 | } |
3230 | // Register the phi but do not transform until whole place transforms |
3231 | igvn.register_new_node_with_optimizer(phi, n); |
3232 | // Add the merge phi to the old Phi |
3233 | while( n->req() > 3 ) n->del_req( n->req()-1 ); |
3234 | igvn.replace_input_of(n, 2, phi); |
3235 | if( hot_idx ) n->add_req(hot_phi); |
3236 | } |
3237 | } |
3238 | |
3239 | |
3240 | // Insert a new IdealLoopTree inserted below me. Turn it into a clone |
3241 | // of self loop tree. Turn self into a loop headed by _head and with |
3242 | // tail being the new merge point. |
3243 | IdealLoopTree *ilt = new IdealLoopTree( phase, _head, _tail ); |
3244 | phase->set_loop(_tail,ilt); // Adjust tail |
3245 | _tail = r; // Self's tail is new merge point |
3246 | phase->set_loop(r,this); |
3247 | ilt->_child = _child; // New guy has my children |
3248 | _child = ilt; // Self has new guy as only child |
3249 | ilt->_parent = this; // new guy has self for parent |
3250 | ilt->_nest = _nest; // Same nesting depth (for now) |
3251 | |
3252 | // Starting with 'ilt', look for child loop trees using the same shared |
3253 | // header. Flatten these out; they will no longer be loops in the end. |
3254 | IdealLoopTree **pilt = &_child; |
3255 | while( ilt ) { |
3256 | if( ilt->_head == _head ) { |
3257 | uint i; |
3258 | for( i = 2; i < _head->req(); i++ ) |
3259 | if( _head->in(i) == ilt->_tail ) |
3260 | break; // Still a loop |
3261 | if( i == _head->req() ) { // No longer a loop |
3262 | // Flatten ilt. Hang ilt's "_next" list from the end of |
3263 | // ilt's '_child' list. Move the ilt's _child up to replace ilt. |
3264 | IdealLoopTree **cp = &ilt->_child; |
3265 | while( *cp ) cp = &(*cp)->_next; // Find end of child list |
3266 | *cp = ilt->_next; // Hang next list at end of child list |
3267 | *pilt = ilt->_child; // Move child up to replace ilt |
3268 | ilt->_head = NULL__null; // Flag as a loop UNIONED into parent |
3269 | ilt = ilt->_child; // Repeat using new ilt |
3270 | continue; // do not advance over ilt->_child |
3271 | } |
3272 | assert( ilt->_tail == hot_tail, "expected to only find the hot inner loop here" )do { if (!(ilt->_tail == hot_tail)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3272, "assert(" "ilt->_tail == hot_tail" ") failed", "expected to only find the hot inner loop here" ); ::breakpoint(); } } while (0); |
3273 | phase->set_loop(_head,ilt); |
3274 | } |
3275 | pilt = &ilt->_child; // Advance to next |
3276 | ilt = *pilt; |
3277 | } |
3278 | |
3279 | if( _child ) fix_parent( _child, this ); |
3280 | } |
3281 | |
3282 | //------------------------------beautify_loops--------------------------------- |
3283 | // Split shared headers and insert loop landing pads. |
3284 | // Insert a LoopNode to replace the RegionNode. |
3285 | // Return TRUE if loop tree is structurally changed. |
3286 | bool IdealLoopTree::beautify_loops( PhaseIdealLoop *phase ) { |
3287 | bool result = false; |
3288 | // Cache parts in locals for easy |
3289 | PhaseIterGVN &igvn = phase->_igvn; |
3290 | |
3291 | igvn.hash_delete(_head); // Yank from hash before hacking edges |
3292 | |
3293 | // Check for multiple fall-in paths. Peel off a landing pad if need be. |
3294 | int fall_in_cnt = 0; |
3295 | for( uint i = 1; i < _head->req(); i++ ) |
3296 | if( !phase->is_member( this, _head->in(i) ) ) |
3297 | fall_in_cnt++; |
3298 | assert( fall_in_cnt, "at least 1 fall-in path" )do { if (!(fall_in_cnt)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3298, "assert(" "fall_in_cnt" ") failed", "at least 1 fall-in path" ); ::breakpoint(); } } while (0); |
3299 | if( fall_in_cnt > 1 ) // Need a loop landing pad to merge fall-ins |
3300 | split_fall_in( phase, fall_in_cnt ); |
3301 | |
3302 | // Swap inputs to the _head and all Phis to move the fall-in edge to |
3303 | // the left. |
3304 | fall_in_cnt = 1; |
3305 | while( phase->is_member( this, _head->in(fall_in_cnt) ) ) |
3306 | fall_in_cnt++; |
3307 | if( fall_in_cnt > 1 ) { |
3308 | // Since I am just swapping inputs I do not need to update def-use info |
3309 | Node *tmp = _head->in(1); |
3310 | igvn.rehash_node_delayed(_head); |
3311 | _head->set_req( 1, _head->in(fall_in_cnt) ); |
3312 | _head->set_req( fall_in_cnt, tmp ); |
3313 | // Swap also all Phis |
3314 | for (DUIterator_Fast imax, i = _head->fast_outs(imax); i < imax; i++) { |
3315 | Node* phi = _head->fast_out(i); |
3316 | if( phi->is_Phi() ) { |
3317 | igvn.rehash_node_delayed(phi); // Yank from hash before hacking edges |
3318 | tmp = phi->in(1); |
3319 | phi->set_req( 1, phi->in(fall_in_cnt) ); |
3320 | phi->set_req( fall_in_cnt, tmp ); |
3321 | } |
3322 | } |
3323 | } |
3324 | assert( !phase->is_member( this, _head->in(1) ), "left edge is fall-in" )do { if (!(!phase->is_member( this, _head->in(1) ))) { ( *g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3324, "assert(" "!phase->is_member( this, _head->in(1) )" ") failed", "left edge is fall-in"); ::breakpoint(); } } while (0); |
3325 | assert( phase->is_member( this, _head->in(2) ), "right edge is loop" )do { if (!(phase->is_member( this, _head->in(2) ))) { ( *g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3325, "assert(" "phase->is_member( this, _head->in(2) )" ") failed", "right edge is loop"); ::breakpoint(); } } while (0); |
3326 | |
3327 | // If I am a shared header (multiple backedges), peel off the many |
3328 | // backedges into a private merge point and use the merge point as |
3329 | // the one true backedge. |
3330 | if (_head->req() > 3) { |
3331 | // Merge the many backedges into a single backedge but leave |
3332 | // the hottest backedge as separate edge for the following peel. |
3333 | if (!_irreducible) { |
3334 | merge_many_backedges( phase ); |
3335 | } |
3336 | |
3337 | // When recursively beautify my children, split_fall_in can change |
3338 | // loop tree structure when I am an irreducible loop. Then the head |
3339 | // of my children has a req() not bigger than 3. Here we need to set |
3340 | // result to true to catch that case in order to tell the caller to |
3341 | // rebuild loop tree. See issue JDK-8244407 for details. |
3342 | result = true; |
3343 | } |
3344 | |
3345 | // If I have one hot backedge, peel off myself loop. |
3346 | // I better be the outermost loop. |
3347 | if (_head->req() > 3 && !_irreducible) { |
3348 | split_outer_loop( phase ); |
3349 | result = true; |
3350 | |
3351 | } else if (!_head->is_Loop() && !_irreducible) { |
3352 | // Make a new LoopNode to replace the old loop head |
3353 | Node *l = new LoopNode( _head->in(1), _head->in(2) ); |
3354 | l = igvn.register_new_node_with_optimizer(l, _head); |
3355 | phase->set_created_loop_node(); |
3356 | // Go ahead and replace _head |
3357 | phase->_igvn.replace_node( _head, l ); |
3358 | _head = l; |
3359 | phase->set_loop(_head, this); |
3360 | } |
3361 | |
3362 | // Now recursively beautify nested loops |
3363 | if( _child ) result |= _child->beautify_loops( phase ); |
3364 | if( _next ) result |= _next ->beautify_loops( phase ); |
3365 | return result; |
3366 | } |
3367 | |
3368 | //------------------------------allpaths_check_safepts---------------------------- |
3369 | // Allpaths backwards scan from loop tail, terminating each path at first safepoint |
3370 | // encountered. Helper for check_safepts. |
3371 | void IdealLoopTree::allpaths_check_safepts(VectorSet &visited, Node_List &stack) { |
3372 | assert(stack.size() == 0, "empty stack")do { if (!(stack.size() == 0)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3372, "assert(" "stack.size() == 0" ") failed", "empty stack" ); ::breakpoint(); } } while (0); |
3373 | stack.push(_tail); |
3374 | visited.clear(); |
3375 | visited.set(_tail->_idx); |
3376 | while (stack.size() > 0) { |
3377 | Node* n = stack.pop(); |
3378 | if (n->is_Call() && n->as_Call()->guaranteed_safepoint()) { |
3379 | // Terminate this path |
3380 | } else if (n->Opcode() == Op_SafePoint) { |
3381 | if (_phase->get_loop(n) != this) { |
3382 | if (_required_safept == NULL__null) _required_safept = new Node_List(); |
3383 | _required_safept->push(n); // save the one closest to the tail |
3384 | } |
3385 | // Terminate this path |
3386 | } else { |
3387 | uint start = n->is_Region() ? 1 : 0; |
3388 | uint end = n->is_Region() && !n->is_Loop() ? n->req() : start + 1; |
3389 | for (uint i = start; i < end; i++) { |
3390 | Node* in = n->in(i); |
3391 | assert(in->is_CFG(), "must be")do { if (!(in->is_CFG())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3391, "assert(" "in->is_CFG()" ") failed", "must be"); :: breakpoint(); } } while (0); |
3392 | if (!visited.test_set(in->_idx) && is_member(_phase->get_loop(in))) { |
3393 | stack.push(in); |
3394 | } |
3395 | } |
3396 | } |
3397 | } |
3398 | } |
3399 | |
3400 | //------------------------------check_safepts---------------------------- |
3401 | // Given dominators, try to find loops with calls that must always be |
3402 | // executed (call dominates loop tail). These loops do not need non-call |
3403 | // safepoints (ncsfpt). |
3404 | // |
3405 | // A complication is that a safepoint in a inner loop may be needed |
3406 | // by an outer loop. In the following, the inner loop sees it has a |
3407 | // call (block 3) on every path from the head (block 2) to the |
3408 | // backedge (arc 3->2). So it deletes the ncsfpt (non-call safepoint) |
3409 | // in block 2, _but_ this leaves the outer loop without a safepoint. |
3410 | // |
3411 | // entry 0 |
3412 | // | |
3413 | // v |
3414 | // outer 1,2 +->1 |
3415 | // | | |
3416 | // | v |
3417 | // | 2<---+ ncsfpt in 2 |
3418 | // |_/|\ | |
3419 | // | v | |
3420 | // inner 2,3 / 3 | call in 3 |
3421 | // / | | |
3422 | // v +--+ |
3423 | // exit 4 |
3424 | // |
3425 | // |
3426 | // This method creates a list (_required_safept) of ncsfpt nodes that must |
3427 | // be protected is created for each loop. When a ncsfpt maybe deleted, it |
3428 | // is first looked for in the lists for the outer loops of the current loop. |
3429 | // |
3430 | // The insights into the problem: |
3431 | // A) counted loops are okay |
3432 | // B) innermost loops are okay (only an inner loop can delete |
3433 | // a ncsfpt needed by an outer loop) |
3434 | // C) a loop is immune from an inner loop deleting a safepoint |
3435 | // if the loop has a call on the idom-path |
3436 | // D) a loop is also immune if it has a ncsfpt (non-call safepoint) on the |
3437 | // idom-path that is not in a nested loop |
3438 | // E) otherwise, an ncsfpt on the idom-path that is nested in an inner |
3439 | // loop needs to be prevented from deletion by an inner loop |
3440 | // |
3441 | // There are two analyses: |
3442 | // 1) The first, and cheaper one, scans the loop body from |
3443 | // tail to head following the idom (immediate dominator) |
3444 | // chain, looking for the cases (C,D,E) above. |
3445 | // Since inner loops are scanned before outer loops, there is summary |
3446 | // information about inner loops. Inner loops can be skipped over |
3447 | // when the tail of an inner loop is encountered. |
3448 | // |
3449 | // 2) The second, invoked if the first fails to find a call or ncsfpt on |
3450 | // the idom path (which is rare), scans all predecessor control paths |
3451 | // from the tail to the head, terminating a path when a call or sfpt |
3452 | // is encountered, to find the ncsfpt's that are closest to the tail. |
3453 | // |
3454 | void IdealLoopTree::check_safepts(VectorSet &visited, Node_List &stack) { |
3455 | // Bottom up traversal |
3456 | IdealLoopTree* ch = _child; |
3457 | if (_child) _child->check_safepts(visited, stack); |
3458 | if (_next) _next ->check_safepts(visited, stack); |
3459 | |
3460 | if (!_head->is_CountedLoop() && !_has_sfpt && _parent != NULL__null && !_irreducible) { |
3461 | bool has_call = false; // call on dom-path |
3462 | bool has_local_ncsfpt = false; // ncsfpt on dom-path at this loop depth |
3463 | Node* nonlocal_ncsfpt = NULL__null; // ncsfpt on dom-path at a deeper depth |
3464 | // Scan the dom-path nodes from tail to head |
3465 | for (Node* n = tail(); n != _head; n = _phase->idom(n)) { |
3466 | if (n->is_Call() && n->as_Call()->guaranteed_safepoint()) { |
3467 | has_call = true; |
3468 | _has_sfpt = 1; // Then no need for a safept! |
3469 | break; |
3470 | } else if (n->Opcode() == Op_SafePoint) { |
3471 | if (_phase->get_loop(n) == this) { |
3472 | has_local_ncsfpt = true; |
3473 | break; |
3474 | } |
3475 | if (nonlocal_ncsfpt == NULL__null) { |
3476 | nonlocal_ncsfpt = n; // save the one closest to the tail |
3477 | } |
3478 | } else { |
3479 | IdealLoopTree* nlpt = _phase->get_loop(n); |
3480 | if (this != nlpt) { |
3481 | // If at an inner loop tail, see if the inner loop has already |
3482 | // recorded seeing a call on the dom-path (and stop.) If not, |
3483 | // jump to the head of the inner loop. |
3484 | assert(is_member(nlpt), "nested loop")do { if (!(is_member(nlpt))) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3484, "assert(" "is_member(nlpt)" ") failed", "nested loop" ); ::breakpoint(); } } while (0); |
3485 | Node* tail = nlpt->_tail; |
3486 | if (tail->in(0)->is_If()) tail = tail->in(0); |
3487 | if (n == tail) { |
3488 | // If inner loop has call on dom-path, so does outer loop |
3489 | if (nlpt->_has_sfpt) { |
3490 | has_call = true; |
3491 | _has_sfpt = 1; |
3492 | break; |
3493 | } |
3494 | // Skip to head of inner loop |
3495 | assert(_phase->is_dominator(_head, nlpt->_head), "inner head dominated by outer head")do { if (!(_phase->is_dominator(_head, nlpt->_head))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3495, "assert(" "_phase->is_dominator(_head, nlpt->_head)" ") failed", "inner head dominated by outer head"); ::breakpoint (); } } while (0); |
3496 | n = nlpt->_head; |
3497 | } |
3498 | } |
3499 | } |
3500 | } |
3501 | // Record safept's that this loop needs preserved when an |
3502 | // inner loop attempts to delete it's safepoints. |
3503 | if (_child != NULL__null && !has_call && !has_local_ncsfpt) { |
3504 | if (nonlocal_ncsfpt != NULL__null) { |
3505 | if (_required_safept == NULL__null) _required_safept = new Node_List(); |
3506 | _required_safept->push(nonlocal_ncsfpt); |
3507 | } else { |
3508 | // Failed to find a suitable safept on the dom-path. Now use |
3509 | // an all paths walk from tail to head, looking for safepoints to preserve. |
3510 | allpaths_check_safepts(visited, stack); |
3511 | } |
3512 | } |
3513 | } |
3514 | } |
3515 | |
3516 | //---------------------------is_deleteable_safept---------------------------- |
3517 | // Is safept not required by an outer loop? |
3518 | bool PhaseIdealLoop::is_deleteable_safept(Node* sfpt) { |
3519 | assert(sfpt->Opcode() == Op_SafePoint, "")do { if (!(sfpt->Opcode() == Op_SafePoint)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3519, "assert(" "sfpt->Opcode() == Op_SafePoint" ") failed" , ""); ::breakpoint(); } } while (0); |
3520 | IdealLoopTree* lp = get_loop(sfpt)->_parent; |
3521 | while (lp != NULL__null) { |
3522 | Node_List* sfpts = lp->_required_safept; |
3523 | if (sfpts != NULL__null) { |
3524 | for (uint i = 0; i < sfpts->size(); i++) { |
3525 | if (sfpt == sfpts->at(i)) |
3526 | return false; |
3527 | } |
3528 | } |
3529 | lp = lp->_parent; |
3530 | } |
3531 | return true; |
3532 | } |
3533 | |
3534 | //---------------------------replace_parallel_iv------------------------------- |
3535 | // Replace parallel induction variable (parallel to trip counter) |
3536 | void PhaseIdealLoop::replace_parallel_iv(IdealLoopTree *loop) { |
3537 | assert(loop->_head->is_CountedLoop(), "")do { if (!(loop->_head->is_CountedLoop())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3537, "assert(" "loop->_head->is_CountedLoop()" ") failed" , ""); ::breakpoint(); } } while (0); |
3538 | CountedLoopNode *cl = loop->_head->as_CountedLoop(); |
3539 | if (!cl->is_valid_counted_loop(T_INT)) |
3540 | return; // skip malformed counted loop |
3541 | Node *incr = cl->incr(); |
3542 | if (incr == NULL__null) |
3543 | return; // Dead loop? |
3544 | Node *init = cl->init_trip(); |
3545 | Node *phi = cl->phi(); |
3546 | int stride_con = cl->stride_con(); |
3547 | |
3548 | // Visit all children, looking for Phis |
3549 | for (DUIterator i = cl->outs(); cl->has_out(i); i++) { |
3550 | Node *out = cl->out(i); |
3551 | // Look for other phis (secondary IVs). Skip dead ones |
3552 | if (!out->is_Phi() || out == phi || !has_node(out)) |
3553 | continue; |
3554 | PhiNode* phi2 = out->as_Phi(); |
3555 | Node *incr2 = phi2->in( LoopNode::LoopBackControl ); |
3556 | // Look for induction variables of the form: X += constant |
3557 | if (phi2->region() != loop->_head || |
3558 | incr2->req() != 3 || |
3559 | incr2->in(1)->uncast() != phi2 || |
3560 | incr2 == incr || |
3561 | incr2->Opcode() != Op_AddI || |
3562 | !incr2->in(2)->is_Con()) |
3563 | continue; |
3564 | |
3565 | // Check for parallel induction variable (parallel to trip counter) |
3566 | // via an affine function. In particular, count-down loops with |
3567 | // count-up array indices are common. We only RCE references off |
3568 | // the trip-counter, so we need to convert all these to trip-counter |
3569 | // expressions. |
3570 | Node *init2 = phi2->in( LoopNode::EntryControl ); |
3571 | int stride_con2 = incr2->in(2)->get_int(); |
3572 | |
3573 | // The ratio of the two strides cannot be represented as an int |
3574 | // if stride_con2 is min_int and stride_con is -1. |
3575 | if (stride_con2 == min_jint && stride_con == -1) { |
3576 | continue; |
3577 | } |
3578 | |
3579 | // The general case here gets a little tricky. We want to find the |
3580 | // GCD of all possible parallel IV's and make a new IV using this |
3581 | // GCD for the loop. Then all possible IVs are simple multiples of |
3582 | // the GCD. In practice, this will cover very few extra loops. |
3583 | // Instead we require 'stride_con2' to be a multiple of 'stride_con', |
3584 | // where +/-1 is the common case, but other integer multiples are |
3585 | // also easy to handle. |
3586 | int ratio_con = stride_con2/stride_con; |
3587 | |
3588 | if ((ratio_con * stride_con) == stride_con2) { // Check for exact |
3589 | #ifndef PRODUCT |
3590 | if (TraceLoopOpts) { |
3591 | tty->print("Parallel IV: %d ", phi2->_idx); |
3592 | loop->dump_head(); |
3593 | } |
3594 | #endif |
3595 | // Convert to using the trip counter. The parallel induction |
3596 | // variable differs from the trip counter by a loop-invariant |
3597 | // amount, the difference between their respective initial values. |
3598 | // It is scaled by the 'ratio_con'. |
3599 | Node* ratio = _igvn.intcon(ratio_con); |
3600 | set_ctrl(ratio, C->root()); |
3601 | Node* ratio_init = new MulINode(init, ratio); |
3602 | _igvn.register_new_node_with_optimizer(ratio_init, init); |
3603 | set_early_ctrl(ratio_init, false); |
3604 | Node* diff = new SubINode(init2, ratio_init); |
3605 | _igvn.register_new_node_with_optimizer(diff, init2); |
3606 | set_early_ctrl(diff, false); |
3607 | Node* ratio_idx = new MulINode(phi, ratio); |
3608 | _igvn.register_new_node_with_optimizer(ratio_idx, phi); |
3609 | set_ctrl(ratio_idx, cl); |
3610 | Node* add = new AddINode(ratio_idx, diff); |
3611 | _igvn.register_new_node_with_optimizer(add); |
3612 | set_ctrl(add, cl); |
3613 | _igvn.replace_node( phi2, add ); |
3614 | // Sometimes an induction variable is unused |
3615 | if (add->outcnt() == 0) { |
3616 | _igvn.remove_dead_node(add); |
3617 | } |
3618 | --i; // deleted this phi; rescan starting with next position |
3619 | continue; |
3620 | } |
3621 | } |
3622 | } |
3623 | |
3624 | void IdealLoopTree::remove_safepoints(PhaseIdealLoop* phase, bool keep_one) { |
3625 | Node* keep = NULL__null; |
3626 | if (keep_one) { |
3627 | // Look for a safepoint on the idom-path. |
3628 | for (Node* i = tail(); i != _head; i = phase->idom(i)) { |
3629 | if (i->Opcode() == Op_SafePoint && phase->get_loop(i) == this) { |
3630 | keep = i; |
3631 | break; // Found one |
3632 | } |
3633 | } |
3634 | } |
3635 | |
3636 | // Don't remove any safepoints if it is requested to keep a single safepoint and |
3637 | // no safepoint was found on idom-path. It is not safe to remove any safepoint |
3638 | // in this case since there's no safepoint dominating all paths in the loop body. |
3639 | bool prune = !keep_one || keep != NULL__null; |
3640 | |
3641 | // Delete other safepoints in this loop. |
3642 | Node_List* sfpts = _safepts; |
3643 | if (prune && sfpts != NULL__null) { |
3644 | assert(keep == NULL || keep->Opcode() == Op_SafePoint, "not safepoint")do { if (!(keep == __null || keep->Opcode() == Op_SafePoint )) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3644, "assert(" "keep == __null || keep->Opcode() == Op_SafePoint" ") failed", "not safepoint"); ::breakpoint(); } } while (0); |
3645 | for (uint i = 0; i < sfpts->size(); i++) { |
3646 | Node* n = sfpts->at(i); |
3647 | assert(phase->get_loop(n) == this, "")do { if (!(phase->get_loop(n) == this)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3647, "assert(" "phase->get_loop(n) == this" ") failed", ""); ::breakpoint(); } } while (0); |
3648 | if (n != keep && phase->is_deleteable_safept(n)) { |
3649 | phase->lazy_replace(n, n->in(TypeFunc::Control)); |
3650 | } |
3651 | } |
3652 | } |
3653 | } |
3654 | |
3655 | //------------------------------counted_loop----------------------------------- |
3656 | // Convert to counted loops where possible |
3657 | void IdealLoopTree::counted_loop( PhaseIdealLoop *phase ) { |
3658 | |
3659 | // For grins, set the inner-loop flag here |
3660 | if (!_child) { |
3661 | if (_head->is_Loop()) _head->as_Loop()->set_inner_loop(); |
3662 | } |
3663 | |
3664 | IdealLoopTree* loop = this; |
3665 | if (_head->is_CountedLoop() || |
3666 | phase->is_counted_loop(_head, loop, T_INT)) { |
3667 | |
3668 | if (LoopStripMiningIter == 0 || (LoopStripMiningIter > 1 && _child == NULL__null)) { |
3669 | // Indicate we do not need a safepoint here |
3670 | _has_sfpt = 1; |
3671 | } |
3672 | |
3673 | // Remove safepoints |
3674 | bool keep_one_sfpt = !(_has_call || _has_sfpt); |
3675 | remove_safepoints(phase, keep_one_sfpt); |
3676 | |
3677 | // Look for induction variables |
3678 | phase->replace_parallel_iv(this); |
3679 | } else if (_head->is_LongCountedLoop() || |
3680 | phase->is_counted_loop(_head, loop, T_LONG)) { |
3681 | remove_safepoints(phase, true); |
3682 | } else { |
3683 | assert(!_head->is_Loop() || !_head->as_Loop()->is_loop_nest_inner_loop(), "transformation to counted loop should not fail")do { if (!(!_head->is_Loop() || !_head->as_Loop()->is_loop_nest_inner_loop ())) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3683, "assert(" "!_head->is_Loop() || !_head->as_Loop()->is_loop_nest_inner_loop()" ") failed", "transformation to counted loop should not fail" ); ::breakpoint(); } } while (0); |
3684 | if (_parent != NULL__null && !_irreducible) { |
3685 | // Not a counted loop. Keep one safepoint. |
3686 | bool keep_one_sfpt = true; |
3687 | remove_safepoints(phase, keep_one_sfpt); |
3688 | } |
3689 | } |
3690 | |
3691 | // Recursively |
3692 | assert(loop->_child != this || (loop->_head->as_Loop()->is_OuterStripMinedLoop() && _head->as_CountedLoop()->is_strip_mined()), "what kind of loop was added?")do { if (!(loop->_child != this || (loop->_head->as_Loop ()->is_OuterStripMinedLoop() && _head->as_CountedLoop ()->is_strip_mined()))) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3692, "assert(" "loop->_child != this || (loop->_head->as_Loop()->is_OuterStripMinedLoop() && _head->as_CountedLoop()->is_strip_mined())" ") failed", "what kind of loop was added?"); ::breakpoint(); } } while (0); |
3693 | assert(loop->_child != this || (loop->_child->_child == NULL && loop->_child->_next == NULL), "would miss some loops")do { if (!(loop->_child != this || (loop->_child->_child == __null && loop->_child->_next == __null))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3693, "assert(" "loop->_child != this || (loop->_child->_child == __null && loop->_child->_next == __null)" ") failed", "would miss some loops"); ::breakpoint(); } } while (0); |
3694 | if (loop->_child && loop->_child != this) loop->_child->counted_loop(phase); |
3695 | if (loop->_next) loop->_next ->counted_loop(phase); |
3696 | } |
3697 | |
3698 | |
3699 | // The Estimated Loop Clone Size: |
3700 | // CloneFactor * (~112% * BodySize + BC) + CC + FanOutTerm, |
3701 | // where BC and CC are totally ad-hoc/magic "body" and "clone" constants, |
3702 | // respectively, used to ensure that the node usage estimates made are on the |
3703 | // safe side, for the most part. The FanOutTerm is an attempt to estimate the |
3704 | // possible additional/excessive nodes generated due to data and control flow |
3705 | // merging, for edges reaching outside the loop. |
3706 | uint IdealLoopTree::est_loop_clone_sz(uint factor) const { |
3707 | |
3708 | precond(0 < factor && factor < 16)do { if (!(0 < factor && factor < 16)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3708, "assert(" "0 < factor && factor < 16" ") failed" , "precond"); ::breakpoint(); } } while (0); |
3709 | |
3710 | uint const bc = 13; |
3711 | uint const cc = 17; |
3712 | uint const sz = _body.size() + (_body.size() + 7) / 2; |
3713 | uint estimate = factor * (sz + bc) + cc; |
3714 | |
3715 | assert((estimate - cc) / factor == sz + bc, "overflow")do { if (!((estimate - cc) / factor == sz + bc)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3715, "assert(" "(estimate - cc) / factor == sz + bc" ") failed" , "overflow"); ::breakpoint(); } } while (0); |
3716 | |
3717 | return estimate + est_loop_flow_merge_sz(); |
3718 | } |
3719 | |
3720 | // The Estimated Loop (full-) Unroll Size: |
3721 | // UnrollFactor * (~106% * BodySize) + CC + FanOutTerm, |
3722 | // where CC is a (totally) ad-hoc/magic "clone" constant, used to ensure that |
3723 | // node usage estimates made are on the safe side, for the most part. This is |
3724 | // a "light" version of the loop clone size calculation (above), based on the |
3725 | // assumption that most of the loop-construct overhead will be unraveled when |
3726 | // (fully) unrolled. Defined for unroll factors larger or equal to one (>=1), |
3727 | // including an overflow check and returning UINT_MAX in case of an overflow. |
3728 | uint IdealLoopTree::est_loop_unroll_sz(uint factor) const { |
3729 | |
3730 | precond(factor > 0)do { if (!(factor > 0)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3730, "assert(" "factor > 0" ") failed", "precond"); ::breakpoint (); } } while (0); |
3731 | |
3732 | // Take into account that after unroll conjoined heads and tails will fold. |
3733 | uint const b0 = _body.size() - EMPTY_LOOP_SIZE; |
3734 | uint const cc = 7; |
3735 | uint const sz = b0 + (b0 + 15) / 16; |
3736 | uint estimate = factor * sz + cc; |
3737 | |
3738 | if ((estimate - cc) / factor != sz) { |
3739 | return UINT_MAX(2147483647 *2U +1U); |
3740 | } |
3741 | |
3742 | return estimate + est_loop_flow_merge_sz(); |
3743 | } |
3744 | |
3745 | // Estimate the growth effect (in nodes) of merging control and data flow when |
3746 | // cloning a loop body, based on the amount of control and data flow reaching |
3747 | // outside of the (current) loop body. |
3748 | uint IdealLoopTree::est_loop_flow_merge_sz() const { |
3749 | |
3750 | uint ctrl_edge_out_cnt = 0; |
3751 | uint data_edge_out_cnt = 0; |
3752 | |
3753 | for (uint i = 0; i < _body.size(); i++) { |
3754 | Node* node = _body.at(i); |
3755 | uint outcnt = node->outcnt(); |
3756 | |
3757 | for (uint k = 0; k < outcnt; k++) { |
3758 | Node* out = node->raw_out(k); |
3759 | if (out == NULL__null) continue; |
3760 | if (out->is_CFG()) { |
3761 | if (!is_member(_phase->get_loop(out))) { |
3762 | ctrl_edge_out_cnt++; |
3763 | } |
3764 | } else if (_phase->has_ctrl(out)) { |
3765 | Node* ctrl = _phase->get_ctrl(out); |
3766 | assert(ctrl != NULL, "must be")do { if (!(ctrl != __null)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3766, "assert(" "ctrl != __null" ") failed", "must be"); :: breakpoint(); } } while (0); |
3767 | assert(ctrl->is_CFG(), "must be")do { if (!(ctrl->is_CFG())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3767, "assert(" "ctrl->is_CFG()" ") failed", "must be"); ::breakpoint(); } } while (0); |
3768 | if (!is_member(_phase->get_loop(ctrl))) { |
3769 | data_edge_out_cnt++; |
3770 | } |
3771 | } |
3772 | } |
3773 | } |
3774 | // Use data and control count (x2.0) in estimate iff both are > 0. This is |
3775 | // a rather pessimistic estimate for the most part, in particular for some |
3776 | // complex loops, but still not enough to capture all loops. |
3777 | if (ctrl_edge_out_cnt > 0 && data_edge_out_cnt > 0) { |
3778 | return 2 * (ctrl_edge_out_cnt + data_edge_out_cnt); |
3779 | } |
3780 | return 0; |
3781 | } |
3782 | |
3783 | #ifndef PRODUCT |
3784 | //------------------------------dump_head-------------------------------------- |
3785 | // Dump 1 liner for loop header info |
3786 | void IdealLoopTree::dump_head() const { |
3787 | tty->sp(2 * _nest); |
3788 | tty->print("Loop: N%d/N%d ", _head->_idx, _tail->_idx); |
3789 | if (_irreducible) tty->print(" IRREDUCIBLE"); |
3790 | Node* entry = _head->is_Loop() ? _head->as_Loop()->skip_strip_mined(-1)->in(LoopNode::EntryControl) : _head->in(LoopNode::EntryControl); |
3791 | Node* predicate = PhaseIdealLoop::find_predicate_insertion_point(entry, Deoptimization::Reason_loop_limit_check); |
3792 | if (predicate != NULL__null ) { |
3793 | tty->print(" limit_check"); |
3794 | entry = PhaseIdealLoop::skip_loop_predicates(entry); |
3795 | } |
3796 | if (UseProfiledLoopPredicate) { |
3797 | predicate = PhaseIdealLoop::find_predicate_insertion_point(entry, Deoptimization::Reason_profile_predicate); |
3798 | if (predicate != NULL__null) { |
3799 | tty->print(" profile_predicated"); |
3800 | entry = PhaseIdealLoop::skip_loop_predicates(entry); |
3801 | } |
3802 | } |
3803 | if (UseLoopPredicate) { |
3804 | predicate = PhaseIdealLoop::find_predicate_insertion_point(entry, Deoptimization::Reason_predicate); |
3805 | if (predicate != NULL__null) { |
3806 | tty->print(" predicated"); |
3807 | } |
3808 | } |
3809 | if (_head->is_CountedLoop()) { |
3810 | CountedLoopNode *cl = _head->as_CountedLoop(); |
3811 | tty->print(" counted"); |
3812 | |
3813 | Node* init_n = cl->init_trip(); |
3814 | if (init_n != NULL__null && init_n->is_Con()) |
3815 | tty->print(" [%d,", cl->init_trip()->get_int()); |
3816 | else |
3817 | tty->print(" [int,"); |
3818 | Node* limit_n = cl->limit(); |
3819 | if (limit_n != NULL__null && limit_n->is_Con()) |
3820 | tty->print("%d),", cl->limit()->get_int()); |
3821 | else |
3822 | tty->print("int),"); |
3823 | int stride_con = cl->stride_con(); |
3824 | if (stride_con > 0) tty->print("+"); |
3825 | tty->print("%d", stride_con); |
3826 | |
3827 | tty->print(" (%0.f iters) ", cl->profile_trip_cnt()); |
3828 | |
3829 | if (cl->is_pre_loop ()) tty->print(" pre" ); |
3830 | if (cl->is_main_loop()) tty->print(" main"); |
3831 | if (cl->is_post_loop()) tty->print(" post"); |
3832 | if (cl->is_vectorized_loop()) tty->print(" vector"); |
3833 | if (cl->range_checks_present()) tty->print(" rc "); |
3834 | if (cl->is_multiversioned()) tty->print(" multi "); |
3835 | } |
3836 | if (_has_call) tty->print(" has_call"); |
3837 | if (_has_sfpt) tty->print(" has_sfpt"); |
3838 | if (_rce_candidate) tty->print(" rce"); |
3839 | if (_safepts != NULL__null && _safepts->size() > 0) { |
3840 | tty->print(" sfpts={"); _safepts->dump_simple(); tty->print(" }"); |
3841 | } |
3842 | if (_required_safept != NULL__null && _required_safept->size() > 0) { |
3843 | tty->print(" req={"); _required_safept->dump_simple(); tty->print(" }"); |
3844 | } |
3845 | if (Verbose) { |
3846 | tty->print(" body={"); _body.dump_simple(); tty->print(" }"); |
3847 | } |
3848 | if (_head->is_Loop() && _head->as_Loop()->is_strip_mined()) { |
3849 | tty->print(" strip_mined"); |
3850 | } |
3851 | tty->cr(); |
3852 | } |
3853 | |
3854 | //------------------------------dump------------------------------------------- |
3855 | // Dump loops by loop tree |
3856 | void IdealLoopTree::dump() const { |
3857 | dump_head(); |
3858 | if (_child) _child->dump(); |
3859 | if (_next) _next ->dump(); |
3860 | } |
3861 | |
3862 | #endif |
3863 | |
3864 | static void log_loop_tree_helper(IdealLoopTree* root, IdealLoopTree* loop, CompileLog* log) { |
3865 | if (loop == root) { |
3866 | if (loop->_child != NULL__null) { |
3867 | log->begin_head("loop_tree"); |
3868 | log->end_head(); |
3869 | log_loop_tree_helper(root, loop->_child, log); |
3870 | log->tail("loop_tree"); |
3871 | assert(loop->_next == NULL, "what?")do { if (!(loop->_next == __null)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3871, "assert(" "loop->_next == __null" ") failed", "what?" ); ::breakpoint(); } } while (0); |
3872 | } |
3873 | } else if (loop != NULL__null) { |
3874 | Node* head = loop->_head; |
3875 | log->begin_head("loop"); |
3876 | log->print(" idx='%d' ", head->_idx); |
3877 | if (loop->_irreducible) log->print("irreducible='1' "); |
3878 | if (head->is_Loop()) { |
3879 | if (head->as_Loop()->is_inner_loop()) log->print("inner_loop='1' "); |
3880 | if (head->as_Loop()->is_partial_peel_loop()) log->print("partial_peel_loop='1' "); |
3881 | } else if (head->is_CountedLoop()) { |
3882 | CountedLoopNode* cl = head->as_CountedLoop(); |
3883 | if (cl->is_pre_loop()) log->print("pre_loop='%d' ", cl->main_idx()); |
3884 | if (cl->is_main_loop()) log->print("main_loop='%d' ", cl->_idx); |
3885 | if (cl->is_post_loop()) log->print("post_loop='%d' ", cl->main_idx()); |
3886 | } |
3887 | log->end_head(); |
3888 | log_loop_tree_helper(root, loop->_child, log); |
3889 | log->tail("loop"); |
3890 | log_loop_tree_helper(root, loop->_next, log); |
3891 | } |
3892 | } |
3893 | |
3894 | void PhaseIdealLoop::log_loop_tree() { |
3895 | if (C->log() != NULL__null) { |
3896 | log_loop_tree_helper(_ltree_root, _ltree_root, C->log()); |
3897 | } |
3898 | } |
3899 | |
3900 | //---------------------collect_potentially_useful_predicates----------------------- |
3901 | // Helper function to collect potentially useful predicates to prevent them from |
3902 | // being eliminated by PhaseIdealLoop::eliminate_useless_predicates |
3903 | void PhaseIdealLoop::collect_potentially_useful_predicates(IdealLoopTree* loop, Unique_Node_List &useful_predicates) { |
3904 | if (loop->_child) { // child |
3905 | collect_potentially_useful_predicates(loop->_child, useful_predicates); |
3906 | } |
3907 | |
3908 | // self (only loops that we can apply loop predication may use their predicates) |
3909 | if (loop->_head->is_Loop() && |
3910 | !loop->_irreducible && |
3911 | !loop->tail()->is_top()) { |
3912 | LoopNode* lpn = loop->_head->as_Loop(); |
3913 | Node* entry = lpn->in(LoopNode::EntryControl); |
3914 | |
3915 | Node* predicate = find_predicate_insertion_point(entry, Deoptimization::Reason_loop_limit_check); |
3916 | if (predicate != NULL__null) { // right pattern that can be used by loop predication |
3917 | assert(entry->in(0)->in(1)->in(1)->Opcode() == Op_Opaque1, "must be")do { if (!(entry->in(0)->in(1)->in(1)->Opcode() == Op_Opaque1)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3917, "assert(" "entry->in(0)->in(1)->in(1)->Opcode() == Op_Opaque1" ") failed", "must be"); ::breakpoint(); } } while (0); |
3918 | useful_predicates.push(entry->in(0)->in(1)->in(1)); // good one |
3919 | entry = skip_loop_predicates(entry); |
3920 | } |
3921 | if (UseProfiledLoopPredicate) { |
3922 | predicate = find_predicate_insertion_point(entry, Deoptimization::Reason_profile_predicate); |
3923 | if (predicate != NULL__null) { // right pattern that can be used by loop predication |
3924 | useful_predicates.push(entry->in(0)->in(1)->in(1)); // good one |
3925 | get_skeleton_predicates(entry, useful_predicates, true); |
3926 | entry = skip_loop_predicates(entry); |
3927 | } |
3928 | } |
3929 | |
3930 | if (UseLoopPredicate) { |
3931 | predicate = find_predicate_insertion_point(entry, Deoptimization::Reason_predicate); |
3932 | if (predicate != NULL__null) { // right pattern that can be used by loop predication |
3933 | useful_predicates.push(entry->in(0)->in(1)->in(1)); // good one |
3934 | get_skeleton_predicates(entry, useful_predicates, true); |
3935 | } |
3936 | } |
3937 | } |
3938 | |
3939 | if (loop->_next) { // sibling |
3940 | collect_potentially_useful_predicates(loop->_next, useful_predicates); |
3941 | } |
3942 | } |
3943 | |
3944 | //------------------------eliminate_useless_predicates----------------------------- |
3945 | // Eliminate all inserted predicates if they could not be used by loop predication. |
3946 | // Note: it will also eliminates loop limits check predicate since it also uses |
3947 | // Opaque1 node (see Parse::add_predicate()). |
3948 | void PhaseIdealLoop::eliminate_useless_predicates() { |
3949 | if (C->predicate_count() == 0 && C->skeleton_predicate_count() == 0) { |
3950 | return; // no predicate left |
3951 | } |
3952 | |
3953 | Unique_Node_List useful_predicates; // to store useful predicates |
3954 | if (C->has_loops()) { |
3955 | collect_potentially_useful_predicates(_ltree_root->_child, useful_predicates); |
3956 | } |
3957 | |
3958 | for (int i = C->predicate_count(); i > 0; i--) { |
3959 | Node* n = C->predicate_opaque1_node(i - 1); |
3960 | assert(n->Opcode() == Op_Opaque1, "must be")do { if (!(n->Opcode() == Op_Opaque1)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3960, "assert(" "n->Opcode() == Op_Opaque1" ") failed", "must be" ); ::breakpoint(); } } while (0); |
3961 | if (!useful_predicates.member(n)) { // not in the useful list |
3962 | _igvn.replace_node(n, n->in(1)); |
3963 | } |
3964 | } |
3965 | |
3966 | for (int i = C->skeleton_predicate_count(); i > 0; i--) { |
3967 | Node* n = C->skeleton_predicate_opaque4_node(i - 1); |
3968 | assert(n->Opcode() == Op_Opaque4, "must be")do { if (!(n->Opcode() == Op_Opaque4)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3968, "assert(" "n->Opcode() == Op_Opaque4" ") failed", "must be" ); ::breakpoint(); } } while (0); |
3969 | if (!useful_predicates.member(n)) { // not in the useful list |
3970 | _igvn.replace_node(n, n->in(2)); |
3971 | } |
3972 | } |
3973 | } |
3974 | |
3975 | //------------------------process_expensive_nodes----------------------------- |
3976 | // Expensive nodes have their control input set to prevent the GVN |
3977 | // from commoning them and as a result forcing the resulting node to |
3978 | // be in a more frequent path. Use CFG information here, to change the |
3979 | // control inputs so that some expensive nodes can be commoned while |
3980 | // not executed more frequently. |
3981 | bool PhaseIdealLoop::process_expensive_nodes() { |
3982 | assert(OptimizeExpensiveOps, "optimization off?")do { if (!(OptimizeExpensiveOps)) { (*g_assert_poison) = 'X'; ; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 3982, "assert(" "OptimizeExpensiveOps" ") failed", "optimization off?" ); ::breakpoint(); } } while (0); |
3983 | |
3984 | // Sort nodes to bring similar nodes together |
3985 | C->sort_expensive_nodes(); |
3986 | |
3987 | bool progress = false; |
3988 | |
3989 | for (int i = 0; i < C->expensive_count(); ) { |
3990 | Node* n = C->expensive_node(i); |
3991 | int start = i; |
3992 | // Find nodes similar to n |
3993 | i++; |
3994 | for (; i < C->expensive_count() && Compile::cmp_expensive_nodes(n, C->expensive_node(i)) == 0; i++); |
3995 | int end = i; |
3996 | // And compare them two by two |
3997 | for (int j = start; j < end; j++) { |
3998 | Node* n1 = C->expensive_node(j); |
3999 | if (is_node_unreachable(n1)) { |
4000 | continue; |
4001 | } |
4002 | for (int k = j+1; k < end; k++) { |
4003 | Node* n2 = C->expensive_node(k); |
4004 | if (is_node_unreachable(n2)) { |
4005 | continue; |
4006 | } |
4007 | |
4008 | assert(n1 != n2, "should be pair of nodes")do { if (!(n1 != n2)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4008, "assert(" "n1 != n2" ") failed", "should be pair of nodes" ); ::breakpoint(); } } while (0); |
4009 | |
4010 | Node* c1 = n1->in(0); |
4011 | Node* c2 = n2->in(0); |
4012 | |
4013 | Node* parent_c1 = c1; |
4014 | Node* parent_c2 = c2; |
4015 | |
4016 | // The call to get_early_ctrl_for_expensive() moves the |
4017 | // expensive nodes up but stops at loops that are in a if |
4018 | // branch. See whether we can exit the loop and move above the |
4019 | // If. |
4020 | if (c1->is_Loop()) { |
4021 | parent_c1 = c1->in(1); |
4022 | } |
4023 | if (c2->is_Loop()) { |
4024 | parent_c2 = c2->in(1); |
4025 | } |
4026 | |
4027 | if (parent_c1 == parent_c2) { |
4028 | _igvn._worklist.push(n1); |
4029 | _igvn._worklist.push(n2); |
4030 | continue; |
4031 | } |
4032 | |
4033 | // Look for identical expensive node up the dominator chain. |
4034 | if (is_dominator(c1, c2)) { |
4035 | c2 = c1; |
4036 | } else if (is_dominator(c2, c1)) { |
4037 | c1 = c2; |
4038 | } else if (parent_c1->is_Proj() && parent_c1->in(0)->is_If() && |
4039 | parent_c2->is_Proj() && parent_c1->in(0) == parent_c2->in(0)) { |
4040 | // Both branches have the same expensive node so move it up |
4041 | // before the if. |
4042 | c1 = c2 = idom(parent_c1->in(0)); |
4043 | } |
4044 | // Do the actual moves |
4045 | if (n1->in(0) != c1) { |
4046 | _igvn.hash_delete(n1); |
4047 | n1->set_req(0, c1); |
4048 | _igvn.hash_insert(n1); |
4049 | _igvn._worklist.push(n1); |
4050 | progress = true; |
4051 | } |
4052 | if (n2->in(0) != c2) { |
4053 | _igvn.hash_delete(n2); |
4054 | n2->set_req(0, c2); |
4055 | _igvn.hash_insert(n2); |
4056 | _igvn._worklist.push(n2); |
4057 | progress = true; |
4058 | } |
4059 | } |
4060 | } |
4061 | } |
4062 | |
4063 | return progress; |
4064 | } |
4065 | |
4066 | #ifdef ASSERT1 |
4067 | bool PhaseIdealLoop::only_has_infinite_loops() { |
4068 | for (IdealLoopTree* l = _ltree_root->_child; l != NULL__null; l = l->_next) { |
4069 | uint i = 1; |
4070 | for (; i < C->root()->req(); i++) { |
4071 | Node* in = C->root()->in(i); |
4072 | if (in != NULL__null && |
4073 | in->Opcode() == Op_Halt && |
4074 | in->in(0)->is_Proj() && |
4075 | in->in(0)->in(0)->Opcode() == Op_NeverBranch && |
4076 | in->in(0)->in(0)->in(0) == l->_head) { |
4077 | break; |
4078 | } |
4079 | } |
4080 | if (i == C->root()->req()) { |
4081 | return false; |
4082 | } |
4083 | } |
4084 | |
4085 | return true; |
4086 | } |
4087 | #endif |
4088 | |
4089 | |
4090 | //============================================================================= |
4091 | //----------------------------build_and_optimize------------------------------- |
4092 | // Create a PhaseLoop. Build the ideal Loop tree. Map each Ideal Node to |
4093 | // its corresponding LoopNode. If 'optimize' is true, do some loop cleanups. |
4094 | void PhaseIdealLoop::build_and_optimize(LoopOptsMode mode) { |
4095 | assert(!C->post_loop_opts_phase(), "no loop opts allowed")do { if (!(!C->post_loop_opts_phase())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4095, "assert(" "!C->post_loop_opts_phase()" ") failed", "no loop opts allowed"); ::breakpoint(); } } while (0); |
4096 | |
4097 | bool do_split_ifs = (mode == LoopOptsDefault); |
4098 | bool skip_loop_opts = (mode == LoopOptsNone); |
4099 | |
4100 | int old_progress = C->major_progress(); |
4101 | uint orig_worklist_size = _igvn._worklist.size(); |
4102 | |
4103 | // Reset major-progress flag for the driver's heuristics |
4104 | C->clear_major_progress(); |
4105 | |
4106 | #ifndef PRODUCT |
4107 | // Capture for later assert |
4108 | uint unique = C->unique(); |
4109 | _loop_invokes++; |
4110 | _loop_work += unique; |
4111 | #endif |
4112 | |
4113 | // True if the method has at least 1 irreducible loop |
4114 | _has_irreducible_loops = false; |
4115 | |
4116 | _created_loop_node = false; |
4117 | |
4118 | VectorSet visited; |
4119 | // Pre-grow the mapping from Nodes to IdealLoopTrees. |
4120 | _nodes.map(C->unique(), NULL__null); |
4121 | memset(_nodes.adr(), 0, wordSize * C->unique()); |
4122 | |
4123 | // Pre-build the top-level outermost loop tree entry |
4124 | _ltree_root = new IdealLoopTree( this, C->root(), C->root() ); |
4125 | // Do not need a safepoint at the top level |
4126 | _ltree_root->_has_sfpt = 1; |
4127 | |
4128 | // Initialize Dominators. |
4129 | // Checked in clone_loop_predicate() during beautify_loops(). |
4130 | _idom_size = 0; |
4131 | _idom = NULL__null; |
4132 | _dom_depth = NULL__null; |
4133 | _dom_stk = NULL__null; |
4134 | |
4135 | // Empty pre-order array |
4136 | allocate_preorders(); |
4137 | |
4138 | // Build a loop tree on the fly. Build a mapping from CFG nodes to |
4139 | // IdealLoopTree entries. Data nodes are NOT walked. |
4140 | build_loop_tree(); |
4141 | // Check for bailout, and return |
4142 | if (C->failing()) { |
4143 | return; |
4144 | } |
4145 | |
4146 | // Verify that the has_loops() flag set at parse time is consistent |
4147 | // with the just built loop tree. With infinite loops, it could be |
4148 | // that one pass of loop opts only finds infinite loops, clears the |
4149 | // has_loops() flag but adds NeverBranch nodes so the next loop opts |
4150 | // verification pass finds a non empty loop tree. When the back edge |
4151 | // is an exception edge, parsing doesn't set has_loops(). |
4152 | assert(_ltree_root->_child == NULL || C->has_loops() || only_has_infinite_loops() || C->has_exception_backedge(), "parsing found no loops but there are some")do { if (!(_ltree_root->_child == __null || C->has_loops () || only_has_infinite_loops() || C->has_exception_backedge ())) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4152, "assert(" "_ltree_root->_child == __null || C->has_loops() || only_has_infinite_loops() || C->has_exception_backedge()" ") failed", "parsing found no loops but there are some"); :: breakpoint(); } } while (0); |
4153 | // No loops after all |
4154 | if( !_ltree_root->_child && !_verify_only ) C->set_has_loops(false); |
4155 | |
4156 | // There should always be an outer loop containing the Root and Return nodes. |
4157 | // If not, we have a degenerate empty program. Bail out in this case. |
4158 | if (!has_node(C->root())) { |
4159 | if (!_verify_only) { |
4160 | C->clear_major_progress(); |
4161 | C->record_method_not_compilable("empty program detected during loop optimization"); |
4162 | } |
4163 | return; |
4164 | } |
4165 | |
4166 | BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2(); |
4167 | // Nothing to do, so get out |
4168 | bool stop_early = !C->has_loops() && !skip_loop_opts && !do_split_ifs && !_verify_me && !_verify_only && |
4169 | !bs->is_gc_specific_loop_opts_pass(mode); |
4170 | bool do_expensive_nodes = C->should_optimize_expensive_nodes(_igvn); |
4171 | bool strip_mined_loops_expanded = bs->strip_mined_loops_expanded(mode); |
4172 | if (stop_early && !do_expensive_nodes) { |
4173 | return; |
4174 | } |
4175 | |
4176 | // Set loop nesting depth |
4177 | _ltree_root->set_nest( 0 ); |
4178 | |
4179 | // Split shared headers and insert loop landing pads. |
4180 | // Do not bother doing this on the Root loop of course. |
4181 | if( !_verify_me && !_verify_only && _ltree_root->_child ) { |
4182 | C->print_method(PHASE_BEFORE_BEAUTIFY_LOOPS, 3); |
4183 | if( _ltree_root->_child->beautify_loops( this ) ) { |
4184 | // Re-build loop tree! |
4185 | _ltree_root->_child = NULL__null; |
4186 | _nodes.clear(); |
4187 | reallocate_preorders(); |
4188 | build_loop_tree(); |
4189 | // Check for bailout, and return |
4190 | if (C->failing()) { |
4191 | return; |
4192 | } |
4193 | // Reset loop nesting depth |
4194 | _ltree_root->set_nest( 0 ); |
4195 | |
4196 | C->print_method(PHASE_AFTER_BEAUTIFY_LOOPS, 3); |
4197 | } |
4198 | } |
4199 | |
4200 | // Build Dominators for elision of NULL checks & loop finding. |
4201 | // Since nodes do not have a slot for immediate dominator, make |
4202 | // a persistent side array for that info indexed on node->_idx. |
4203 | _idom_size = C->unique(); |
4204 | _idom = NEW_RESOURCE_ARRAY( Node*, _idom_size )(Node**) resource_allocate_bytes((_idom_size) * sizeof(Node*) ); |
4205 | _dom_depth = NEW_RESOURCE_ARRAY( uint, _idom_size )(uint*) resource_allocate_bytes((_idom_size) * sizeof(uint)); |
4206 | _dom_stk = NULL__null; // Allocated on demand in recompute_dom_depth |
4207 | memset( _dom_depth, 0, _idom_size * sizeof(uint) ); |
4208 | |
4209 | Dominators(); |
4210 | |
4211 | if (!_verify_only) { |
4212 | // As a side effect, Dominators removed any unreachable CFG paths |
4213 | // into RegionNodes. It doesn't do this test against Root, so |
4214 | // we do it here. |
4215 | for( uint i = 1; i < C->root()->req(); i++ ) { |
4216 | if( !_nodes[C->root()->in(i)->_idx] ) { // Dead path into Root? |
4217 | _igvn.delete_input_of(C->root(), i); |
4218 | i--; // Rerun same iteration on compressed edges |
4219 | } |
4220 | } |
4221 | |
4222 | // Given dominators, try to find inner loops with calls that must |
4223 | // always be executed (call dominates loop tail). These loops do |
4224 | // not need a separate safepoint. |
4225 | Node_List cisstack; |
4226 | _ltree_root->check_safepts(visited, cisstack); |
4227 | } |
4228 | |
4229 | // Walk the DATA nodes and place into loops. Find earliest control |
4230 | // node. For CFG nodes, the _nodes array starts out and remains |
4231 | // holding the associated IdealLoopTree pointer. For DATA nodes, the |
4232 | // _nodes array holds the earliest legal controlling CFG node. |
4233 | |
4234 | // Allocate stack with enough space to avoid frequent realloc |
4235 | int stack_size = (C->live_nodes() >> 1) + 16; // (live_nodes>>1)+16 from Java2D stats |
4236 | Node_Stack nstack(stack_size); |
4237 | |
4238 | visited.clear(); |
4239 | Node_List worklist; |
4240 | // Don't need C->root() on worklist since |
4241 | // it will be processed among C->top() inputs |
4242 | worklist.push(C->top()); |
4243 | visited.set(C->top()->_idx); // Set C->top() as visited now |
4244 | build_loop_early( visited, worklist, nstack ); |
4245 | |
4246 | // Given early legal placement, try finding counted loops. This placement |
4247 | // is good enough to discover most loop invariants. |
4248 | if (!_verify_me && !_verify_only && !strip_mined_loops_expanded) { |
4249 | _ltree_root->counted_loop( this ); |
4250 | } |
4251 | |
4252 | // Find latest loop placement. Find ideal loop placement. |
4253 | visited.clear(); |
4254 | init_dom_lca_tags(); |
4255 | // Need C->root() on worklist when processing outs |
4256 | worklist.push(C->root()); |
4257 | NOT_PRODUCT( C->verify_graph_edges(); )C->verify_graph_edges(); |
4258 | worklist.push(C->top()); |
4259 | build_loop_late( visited, worklist, nstack ); |
4260 | |
4261 | if (_verify_only) { |
4262 | C->restore_major_progress(old_progress); |
4263 | assert(C->unique() == unique, "verification mode made Nodes? ? ?")do { if (!(C->unique() == unique)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4263, "assert(" "C->unique() == unique" ") failed", "verification mode made Nodes? ? ?" ); ::breakpoint(); } } while (0); |
4264 | assert(_igvn._worklist.size() == orig_worklist_size, "shouldn't push anything")do { if (!(_igvn._worklist.size() == orig_worklist_size)) { ( *g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4264, "assert(" "_igvn._worklist.size() == orig_worklist_size" ") failed", "shouldn't push anything"); ::breakpoint(); } } while (0); |
4265 | return; |
4266 | } |
4267 | |
4268 | // clear out the dead code after build_loop_late |
4269 | while (_deadlist.size()) { |
4270 | _igvn.remove_globally_dead_node(_deadlist.pop()); |
4271 | } |
4272 | |
4273 | if (stop_early) { |
4274 | assert(do_expensive_nodes, "why are we here?")do { if (!(do_expensive_nodes)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4274, "assert(" "do_expensive_nodes" ") failed", "why are we here?" ); ::breakpoint(); } } while (0); |
4275 | if (process_expensive_nodes()) { |
4276 | // If we made some progress when processing expensive nodes then |
4277 | // the IGVN may modify the graph in a way that will allow us to |
4278 | // make some more progress: we need to try processing expensive |
4279 | // nodes again. |
4280 | C->set_major_progress(); |
4281 | } |
4282 | return; |
4283 | } |
4284 | |
4285 | // Some parser-inserted loop predicates could never be used by loop |
4286 | // predication or they were moved away from loop during some optimizations. |
4287 | // For example, peeling. Eliminate them before next loop optimizations. |
4288 | eliminate_useless_predicates(); |
4289 | |
4290 | #ifndef PRODUCT |
4291 | C->verify_graph_edges(); |
4292 | if (_verify_me) { // Nested verify pass? |
4293 | // Check to see if the verify mode is broken |
4294 | assert(C->unique() == unique, "non-optimize mode made Nodes? ? ?")do { if (!(C->unique() == unique)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4294, "assert(" "C->unique() == unique" ") failed", "non-optimize mode made Nodes? ? ?" ); ::breakpoint(); } } while (0); |
4295 | return; |
4296 | } |
4297 | if (VerifyLoopOptimizations) verify(); |
4298 | if (TraceLoopOpts && C->has_loops()) { |
4299 | _ltree_root->dump(); |
4300 | } |
4301 | #endif |
4302 | |
4303 | if (skip_loop_opts) { |
4304 | C->restore_major_progress(old_progress); |
4305 | return; |
4306 | } |
4307 | |
4308 | if (mode == LoopOptsMaxUnroll) { |
4309 | for (LoopTreeIterator iter(_ltree_root); !iter.done(); iter.next()) { |
4310 | IdealLoopTree* lpt = iter.current(); |
4311 | if (lpt->is_innermost() && lpt->_allow_optimizations && !lpt->_has_call && lpt->is_counted()) { |
4312 | lpt->compute_trip_count(this); |
4313 | if (!lpt->do_one_iteration_loop(this) && |
4314 | !lpt->do_remove_empty_loop(this)) { |
4315 | AutoNodeBudget node_budget(this); |
4316 | if (lpt->_head->as_CountedLoop()->is_normal_loop() && |
4317 | lpt->policy_maximally_unroll(this)) { |
4318 | memset( worklist.adr(), 0, worklist.Size()*sizeof(Node*) ); |
4319 | do_maximally_unroll(lpt, worklist); |
4320 | } |
4321 | } |
4322 | } |
4323 | } |
4324 | |
4325 | C->restore_major_progress(old_progress); |
4326 | return; |
4327 | } |
4328 | |
4329 | if (bs->optimize_loops(this, mode, visited, nstack, worklist)) { |
4330 | return; |
4331 | } |
4332 | |
4333 | if (ReassociateInvariants && !C->major_progress()) { |
4334 | // Reassociate invariants and prep for split_thru_phi |
4335 | for (LoopTreeIterator iter(_ltree_root); !iter.done(); iter.next()) { |
4336 | IdealLoopTree* lpt = iter.current(); |
4337 | if (!lpt->is_loop()) { |
4338 | continue; |
4339 | } |
4340 | Node* head = lpt->_head; |
4341 | if (!head->is_BaseCountedLoop() || !lpt->is_innermost()) continue; |
4342 | |
4343 | // check for vectorized loops, any reassociation of invariants was already done |
4344 | if (head->is_CountedLoop()) { |
4345 | if (head->as_CountedLoop()->is_unroll_only()) { |
4346 | continue; |
4347 | } else { |
4348 | AutoNodeBudget node_budget(this); |
4349 | lpt->reassociate_invariants(this); |
4350 | } |
4351 | } |
4352 | // Because RCE opportunities can be masked by split_thru_phi, |
4353 | // look for RCE candidates and inhibit split_thru_phi |
4354 | // on just their loop-phi's for this pass of loop opts |
4355 | if (SplitIfBlocks && do_split_ifs && |
4356 | (lpt->policy_range_check(this, true, T_LONG) || |
4357 | (head->is_CountedLoop() && lpt->policy_range_check(this, true, T_INT)))) { |
4358 | lpt->_rce_candidate = 1; // = true |
4359 | } |
4360 | } |
4361 | } |
4362 | |
4363 | // Check for aggressive application of split-if and other transforms |
4364 | // that require basic-block info (like cloning through Phi's) |
4365 | if (!C->major_progress() && SplitIfBlocks && do_split_ifs) { |
4366 | visited.clear(); |
4367 | split_if_with_blocks( visited, nstack); |
4368 | NOT_PRODUCT( if( VerifyLoopOptimizations ) verify(); )if( VerifyLoopOptimizations ) verify();; |
4369 | } |
4370 | |
4371 | if (!C->major_progress() && do_expensive_nodes && process_expensive_nodes()) { |
4372 | C->set_major_progress(); |
4373 | } |
4374 | |
4375 | // Perform loop predication before iteration splitting |
4376 | if (C->has_loops() && !C->major_progress() && (C->predicate_count() > 0)) { |
4377 | _ltree_root->_child->loop_predication(this); |
4378 | } |
4379 | |
4380 | if (OptimizeFill && UseLoopPredicate && C->has_loops() && !C->major_progress()) { |
4381 | if (do_intrinsify_fill()) { |
4382 | C->set_major_progress(); |
4383 | } |
4384 | } |
4385 | |
4386 | // Perform iteration-splitting on inner loops. Split iterations to avoid |
4387 | // range checks or one-shot null checks. |
4388 | |
4389 | // If split-if's didn't hack the graph too bad (no CFG changes) |
4390 | // then do loop opts. |
4391 | if (C->has_loops() && !C->major_progress()) { |
4392 | memset( worklist.adr(), 0, worklist.Size()*sizeof(Node*) ); |
4393 | _ltree_root->_child->iteration_split( this, worklist ); |
4394 | // No verify after peeling! GCM has hoisted code out of the loop. |
4395 | // After peeling, the hoisted code could sink inside the peeled area. |
4396 | // The peeling code does not try to recompute the best location for |
4397 | // all the code before the peeled area, so the verify pass will always |
4398 | // complain about it. |
4399 | } |
4400 | |
4401 | // Check for bailout, and return |
4402 | if (C->failing()) { |
4403 | return; |
4404 | } |
4405 | |
4406 | // Do verify graph edges in any case |
4407 | NOT_PRODUCT( C->verify_graph_edges(); )C->verify_graph_edges();; |
4408 | |
4409 | if (!do_split_ifs) { |
4410 | // We saw major progress in Split-If to get here. We forced a |
4411 | // pass with unrolling and not split-if, however more split-if's |
4412 | // might make progress. If the unrolling didn't make progress |
4413 | // then the major-progress flag got cleared and we won't try |
4414 | // another round of Split-If. In particular the ever-common |
4415 | // instance-of/check-cast pattern requires at least 2 rounds of |
4416 | // Split-If to clear out. |
4417 | C->set_major_progress(); |
4418 | } |
4419 | |
4420 | // Repeat loop optimizations if new loops were seen |
4421 | if (created_loop_node()) { |
4422 | C->set_major_progress(); |
4423 | } |
4424 | |
4425 | // Keep loop predicates and perform optimizations with them |
4426 | // until no more loop optimizations could be done. |
4427 | // After that switch predicates off and do more loop optimizations. |
4428 | if (!C->major_progress() && (C->predicate_count() > 0)) { |
4429 | C->cleanup_loop_predicates(_igvn); |
4430 | if (TraceLoopOpts) { |
4431 | tty->print_cr("PredicatesOff"); |
4432 | } |
4433 | C->set_major_progress(); |
4434 | } |
4435 | |
4436 | // Convert scalar to superword operations at the end of all loop opts. |
4437 | if (UseSuperWord && C->has_loops() && !C->major_progress()) { |
4438 | // SuperWord transform |
4439 | SuperWord sw(this); |
4440 | for (LoopTreeIterator iter(_ltree_root); !iter.done(); iter.next()) { |
4441 | IdealLoopTree* lpt = iter.current(); |
4442 | if (lpt->is_counted()) { |
4443 | CountedLoopNode *cl = lpt->_head->as_CountedLoop(); |
4444 | |
4445 | if (PostLoopMultiversioning && cl->is_rce_post_loop() && !cl->is_vectorized_loop()) { |
4446 | // Check that the rce'd post loop is encountered first, multiversion after all |
4447 | // major main loop optimization are concluded |
4448 | if (!C->major_progress()) { |
4449 | IdealLoopTree *lpt_next = lpt->_next; |
4450 | if (lpt_next && lpt_next->is_counted()) { |
4451 | CountedLoopNode *cl = lpt_next->_head->as_CountedLoop(); |
4452 | has_range_checks(lpt_next); |
4453 | if (cl->is_post_loop() && cl->range_checks_present()) { |
4454 | if (!cl->is_multiversioned()) { |
4455 | if (multi_version_post_loops(lpt, lpt_next) == false) { |
4456 | // Cause the rce loop to be optimized away if we fail |
4457 | cl->mark_is_multiversioned(); |
4458 | cl->set_slp_max_unroll(0); |
4459 | poison_rce_post_loop(lpt); |
4460 | } |
4461 | } |
4462 | } |
4463 | } |
4464 | sw.transform_loop(lpt, true); |
4465 | } |
4466 | } else if (cl->is_main_loop()) { |
4467 | sw.transform_loop(lpt, true); |
4468 | } |
4469 | } |
4470 | } |
4471 | } |
4472 | |
4473 | // disable assert until issue with split_flow_path is resolved (6742111) |
4474 | // assert(!_has_irreducible_loops || C->parsed_irreducible_loop() || C->is_osr_compilation(), |
4475 | // "shouldn't introduce irreducible loops"); |
4476 | } |
4477 | |
4478 | #ifndef PRODUCT |
4479 | //------------------------------print_statistics------------------------------- |
4480 | int PhaseIdealLoop::_loop_invokes=0;// Count of PhaseIdealLoop invokes |
4481 | int PhaseIdealLoop::_loop_work=0; // Sum of PhaseIdealLoop x unique |
4482 | volatile int PhaseIdealLoop::_long_loop_candidates=0; // Number of long loops seen |
4483 | volatile int PhaseIdealLoop::_long_loop_nests=0; // Number of long loops successfully transformed to a nest |
4484 | volatile int PhaseIdealLoop::_long_loop_counted_loops=0; // Number of long loops successfully transformed to a counted loop |
4485 | void PhaseIdealLoop::print_statistics() { |
4486 | tty->print_cr("PhaseIdealLoop=%d, sum _unique=%d, long loops=%d/%d/%d", _loop_invokes, _loop_work, _long_loop_counted_loops, _long_loop_nests, _long_loop_candidates); |
4487 | } |
4488 | |
4489 | //------------------------------verify----------------------------------------- |
4490 | // Build a verify-only PhaseIdealLoop, and see that it agrees with me. |
4491 | static int fail; // debug only, so its multi-thread dont care |
4492 | void PhaseIdealLoop::verify() const { |
4493 | int old_progress = C->major_progress(); |
4494 | ResourceMark rm; |
4495 | PhaseIdealLoop loop_verify(_igvn, this); |
4496 | VectorSet visited; |
4497 | |
4498 | fail = 0; |
4499 | verify_compare(C->root(), &loop_verify, visited); |
4500 | assert(fail == 0, "verify loops failed")do { if (!(fail == 0)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4500, "assert(" "fail == 0" ") failed", "verify loops failed" ); ::breakpoint(); } } while (0); |
4501 | // Verify loop structure is the same |
4502 | _ltree_root->verify_tree(loop_verify._ltree_root, NULL__null); |
4503 | // Reset major-progress. It was cleared by creating a verify version of |
4504 | // PhaseIdealLoop. |
4505 | C->restore_major_progress(old_progress); |
4506 | } |
4507 | |
4508 | //------------------------------verify_compare--------------------------------- |
4509 | // Make sure me and the given PhaseIdealLoop agree on key data structures |
4510 | void PhaseIdealLoop::verify_compare( Node *n, const PhaseIdealLoop *loop_verify, VectorSet &visited ) const { |
4511 | if( !n ) return; |
4512 | if( visited.test_set( n->_idx ) ) return; |
4513 | if( !_nodes[n->_idx] ) { // Unreachable |
4514 | assert( !loop_verify->_nodes[n->_idx], "both should be unreachable" )do { if (!(!loop_verify->_nodes[n->_idx])) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4514, "assert(" "!loop_verify->_nodes[n->_idx]" ") failed" , "both should be unreachable"); ::breakpoint(); } } while (0 ); |
4515 | return; |
4516 | } |
4517 | |
4518 | uint i; |
4519 | for( i = 0; i < n->req(); i++ ) |
4520 | verify_compare( n->in(i), loop_verify, visited ); |
4521 | |
4522 | // Check the '_nodes' block/loop structure |
4523 | i = n->_idx; |
4524 | if( has_ctrl(n) ) { // We have control; verify has loop or ctrl |
4525 | if( _nodes[i] != loop_verify->_nodes[i] && |
4526 | get_ctrl_no_update(n) != loop_verify->get_ctrl_no_update(n) ) { |
4527 | tty->print("Mismatched control setting for: "); |
4528 | n->dump(); |
4529 | if( fail++ > 10 ) return; |
4530 | Node *c = get_ctrl_no_update(n); |
4531 | tty->print("We have it as: "); |
4532 | if( c->in(0) ) c->dump(); |
4533 | else tty->print_cr("N%d",c->_idx); |
4534 | tty->print("Verify thinks: "); |
4535 | if( loop_verify->has_ctrl(n) ) |
4536 | loop_verify->get_ctrl_no_update(n)->dump(); |
4537 | else |
4538 | loop_verify->get_loop_idx(n)->dump(); |
4539 | tty->cr(); |
4540 | } |
4541 | } else { // We have a loop |
4542 | IdealLoopTree *us = get_loop_idx(n); |
4543 | if( loop_verify->has_ctrl(n) ) { |
4544 | tty->print("Mismatched loop setting for: "); |
4545 | n->dump(); |
4546 | if( fail++ > 10 ) return; |
4547 | tty->print("We have it as: "); |
4548 | us->dump(); |
4549 | tty->print("Verify thinks: "); |
4550 | loop_verify->get_ctrl_no_update(n)->dump(); |
4551 | tty->cr(); |
4552 | } else if (!C->major_progress()) { |
4553 | // Loop selection can be messed up if we did a major progress |
4554 | // operation, like split-if. Do not verify in that case. |
4555 | IdealLoopTree *them = loop_verify->get_loop_idx(n); |
4556 | if( us->_head != them->_head || us->_tail != them->_tail ) { |
4557 | tty->print("Unequals loops for: "); |
4558 | n->dump(); |
4559 | if( fail++ > 10 ) return; |
4560 | tty->print("We have it as: "); |
4561 | us->dump(); |
4562 | tty->print("Verify thinks: "); |
4563 | them->dump(); |
4564 | tty->cr(); |
4565 | } |
4566 | } |
4567 | } |
4568 | |
4569 | // Check for immediate dominators being equal |
4570 | if( i >= _idom_size ) { |
4571 | if( !n->is_CFG() ) return; |
4572 | tty->print("CFG Node with no idom: "); |
4573 | n->dump(); |
4574 | return; |
4575 | } |
4576 | if( !n->is_CFG() ) return; |
4577 | if( n == C->root() ) return; // No IDOM here |
4578 | |
4579 | assert(n->_idx == i, "sanity")do { if (!(n->_idx == i)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4579, "assert(" "n->_idx == i" ") failed", "sanity"); :: breakpoint(); } } while (0); |
4580 | Node *id = idom_no_update(n); |
4581 | if( id != loop_verify->idom_no_update(n) ) { |
4582 | tty->print("Unequals idoms for: "); |
4583 | n->dump(); |
4584 | if( fail++ > 10 ) return; |
4585 | tty->print("We have it as: "); |
4586 | id->dump(); |
4587 | tty->print("Verify thinks: "); |
4588 | loop_verify->idom_no_update(n)->dump(); |
4589 | tty->cr(); |
4590 | } |
4591 | |
4592 | } |
4593 | |
4594 | //------------------------------verify_tree------------------------------------ |
4595 | // Verify that tree structures match. Because the CFG can change, siblings |
4596 | // within the loop tree can be reordered. We attempt to deal with that by |
4597 | // reordering the verify's loop tree if possible. |
4598 | void IdealLoopTree::verify_tree(IdealLoopTree *loop, const IdealLoopTree *parent) const { |
4599 | assert( _parent == parent, "Badly formed loop tree" )do { if (!(_parent == parent)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4599, "assert(" "_parent == parent" ") failed", "Badly formed loop tree" ); ::breakpoint(); } } while (0); |
4600 | |
4601 | // Siblings not in same order? Attempt to re-order. |
4602 | if( _head != loop->_head ) { |
4603 | // Find _next pointer to update |
4604 | IdealLoopTree **pp = &loop->_parent->_child; |
4605 | while( *pp != loop ) |
4606 | pp = &((*pp)->_next); |
4607 | // Find proper sibling to be next |
4608 | IdealLoopTree **nn = &loop->_next; |
4609 | while( (*nn) && (*nn)->_head != _head ) |
4610 | nn = &((*nn)->_next); |
4611 | |
4612 | // Check for no match. |
4613 | if( !(*nn) ) { |
4614 | // Annoyingly, irreducible loops can pick different headers |
4615 | // after a major_progress operation, so the rest of the loop |
4616 | // tree cannot be matched. |
4617 | if (_irreducible && Compile::current()->major_progress()) return; |
4618 | assert( 0, "failed to match loop tree" )do { if (!(0)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4618, "assert(" "0" ") failed", "failed to match loop tree" ); ::breakpoint(); } } while (0); |
4619 | } |
4620 | |
4621 | // Move (*nn) to (*pp) |
4622 | IdealLoopTree *hit = *nn; |
4623 | *nn = hit->_next; |
4624 | hit->_next = loop; |
4625 | *pp = loop; |
4626 | loop = hit; |
4627 | // Now try again to verify |
4628 | } |
4629 | |
4630 | assert( _head == loop->_head , "mismatched loop head" )do { if (!(_head == loop->_head)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4630, "assert(" "_head == loop->_head" ") failed", "mismatched loop head" ); ::breakpoint(); } } while (0); |
4631 | Node *tail = _tail; // Inline a non-updating version of |
4632 | while( !tail->in(0) ) // the 'tail()' call. |
4633 | tail = tail->in(1); |
4634 | assert( tail == loop->_tail, "mismatched loop tail" )do { if (!(tail == loop->_tail)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4634, "assert(" "tail == loop->_tail" ") failed", "mismatched loop tail" ); ::breakpoint(); } } while (0); |
4635 | |
4636 | // Counted loops that are guarded should be able to find their guards |
4637 | if( _head->is_CountedLoop() && _head->as_CountedLoop()->is_main_loop() ) { |
4638 | CountedLoopNode *cl = _head->as_CountedLoop(); |
4639 | Node *init = cl->init_trip(); |
4640 | Node *ctrl = cl->in(LoopNode::EntryControl); |
4641 | assert( ctrl->Opcode() == Op_IfTrue || ctrl->Opcode() == Op_IfFalse, "" )do { if (!(ctrl->Opcode() == Op_IfTrue || ctrl->Opcode( ) == Op_IfFalse)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4641, "assert(" "ctrl->Opcode() == Op_IfTrue || ctrl->Opcode() == Op_IfFalse" ") failed", ""); ::breakpoint(); } } while (0); |
4642 | Node *iff = ctrl->in(0); |
4643 | assert( iff->Opcode() == Op_If, "" )do { if (!(iff->Opcode() == Op_If)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4643, "assert(" "iff->Opcode() == Op_If" ") failed", "") ; ::breakpoint(); } } while (0); |
4644 | Node *bol = iff->in(1); |
4645 | assert( bol->Opcode() == Op_Bool, "" )do { if (!(bol->Opcode() == Op_Bool)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4645, "assert(" "bol->Opcode() == Op_Bool" ") failed", "" ); ::breakpoint(); } } while (0); |
4646 | Node *cmp = bol->in(1); |
4647 | assert( cmp->Opcode() == Op_CmpI, "" )do { if (!(cmp->Opcode() == Op_CmpI)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4647, "assert(" "cmp->Opcode() == Op_CmpI" ") failed", "" ); ::breakpoint(); } } while (0); |
4648 | Node *add = cmp->in(1); |
4649 | Node *opaq; |
4650 | if( add->Opcode() == Op_Opaque1 ) { |
4651 | opaq = add; |
4652 | } else { |
4653 | assert( add->Opcode() == Op_AddI || add->Opcode() == Op_ConI , "" )do { if (!(add->Opcode() == Op_AddI || add->Opcode() == Op_ConI)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4653, "assert(" "add->Opcode() == Op_AddI || add->Opcode() == Op_ConI" ") failed", ""); ::breakpoint(); } } while (0); |
4654 | assert( add == init, "" )do { if (!(add == init)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4654, "assert(" "add == init" ") failed", ""); ::breakpoint (); } } while (0); |
4655 | opaq = cmp->in(2); |
4656 | } |
4657 | assert( opaq->Opcode() == Op_Opaque1, "" )do { if (!(opaq->Opcode() == Op_Opaque1)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4657, "assert(" "opaq->Opcode() == Op_Opaque1" ") failed" , ""); ::breakpoint(); } } while (0); |
4658 | |
4659 | } |
4660 | |
4661 | if (_child != NULL__null) _child->verify_tree(loop->_child, this); |
4662 | if (_next != NULL__null) _next ->verify_tree(loop->_next, parent); |
4663 | // Innermost loops need to verify loop bodies, |
4664 | // but only if no 'major_progress' |
4665 | int fail = 0; |
4666 | if (!Compile::current()->major_progress() && _child == NULL__null) { |
4667 | for( uint i = 0; i < _body.size(); i++ ) { |
4668 | Node *n = _body.at(i); |
4669 | if (n->outcnt() == 0) continue; // Ignore dead |
4670 | uint j; |
4671 | for( j = 0; j < loop->_body.size(); j++ ) |
4672 | if( loop->_body.at(j) == n ) |
4673 | break; |
4674 | if( j == loop->_body.size() ) { // Not found in loop body |
4675 | // Last ditch effort to avoid assertion: Its possible that we |
4676 | // have some users (so outcnt not zero) but are still dead. |
4677 | // Try to find from root. |
4678 | if (Compile::current()->root()->find(n->_idx)) { |
4679 | fail++; |
4680 | tty->print("We have that verify does not: "); |
4681 | n->dump(); |
4682 | } |
4683 | } |
4684 | } |
4685 | for( uint i2 = 0; i2 < loop->_body.size(); i2++ ) { |
4686 | Node *n = loop->_body.at(i2); |
4687 | if (n->outcnt() == 0) continue; // Ignore dead |
4688 | uint j; |
4689 | for( j = 0; j < _body.size(); j++ ) |
4690 | if( _body.at(j) == n ) |
4691 | break; |
4692 | if( j == _body.size() ) { // Not found in loop body |
4693 | // Last ditch effort to avoid assertion: Its possible that we |
4694 | // have some users (so outcnt not zero) but are still dead. |
4695 | // Try to find from root. |
4696 | if (Compile::current()->root()->find(n->_idx)) { |
4697 | fail++; |
4698 | tty->print("Verify has that we do not: "); |
4699 | n->dump(); |
4700 | } |
4701 | } |
4702 | } |
4703 | assert( !fail, "loop body mismatch" )do { if (!(!fail)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4703, "assert(" "!fail" ") failed", "loop body mismatch"); :: breakpoint(); } } while (0); |
4704 | } |
4705 | } |
4706 | |
4707 | #endif |
4708 | |
4709 | //------------------------------set_idom--------------------------------------- |
4710 | void PhaseIdealLoop::set_idom(Node* d, Node* n, uint dom_depth) { |
4711 | uint idx = d->_idx; |
4712 | if (idx >= _idom_size) { |
4713 | uint newsize = next_power_of_2(idx); |
4714 | _idom = REALLOC_RESOURCE_ARRAY( Node*, _idom,_idom_size,newsize)(Node**) resource_reallocate_bytes((char*)(_idom), (_idom_size ) * sizeof(Node*), (newsize) * sizeof(Node*)); |
4715 | _dom_depth = REALLOC_RESOURCE_ARRAY( uint, _dom_depth,_idom_size,newsize)(uint*) resource_reallocate_bytes((char*)(_dom_depth), (_idom_size ) * sizeof(uint), (newsize) * sizeof(uint)); |
4716 | memset( _dom_depth + _idom_size, 0, (newsize - _idom_size) * sizeof(uint) ); |
4717 | _idom_size = newsize; |
4718 | } |
4719 | _idom[idx] = n; |
4720 | _dom_depth[idx] = dom_depth; |
4721 | } |
4722 | |
4723 | //------------------------------recompute_dom_depth--------------------------------------- |
4724 | // The dominator tree is constructed with only parent pointers. |
4725 | // This recomputes the depth in the tree by first tagging all |
4726 | // nodes as "no depth yet" marker. The next pass then runs up |
4727 | // the dom tree from each node marked "no depth yet", and computes |
4728 | // the depth on the way back down. |
4729 | void PhaseIdealLoop::recompute_dom_depth() { |
4730 | uint no_depth_marker = C->unique(); |
4731 | uint i; |
4732 | // Initialize depth to "no depth yet" and realize all lazy updates |
4733 | for (i = 0; i < _idom_size; i++) { |
4734 | // Only indices with a _dom_depth has a Node* or NULL (otherwise uninitalized). |
4735 | if (_dom_depth[i] > 0 && _idom[i] != NULL__null) { |
4736 | _dom_depth[i] = no_depth_marker; |
4737 | |
4738 | // heal _idom if it has a fwd mapping in _nodes |
4739 | if (_idom[i]->in(0) == NULL__null) { |
4740 | idom(i); |
4741 | } |
4742 | } |
4743 | } |
4744 | if (_dom_stk == NULL__null) { |
4745 | uint init_size = C->live_nodes() / 100; // Guess that 1/100 is a reasonable initial size. |
4746 | if (init_size < 10) init_size = 10; |
4747 | _dom_stk = new GrowableArray<uint>(init_size); |
4748 | } |
4749 | // Compute new depth for each node. |
4750 | for (i = 0; i < _idom_size; i++) { |
4751 | uint j = i; |
4752 | // Run up the dom tree to find a node with a depth |
4753 | while (_dom_depth[j] == no_depth_marker) { |
4754 | _dom_stk->push(j); |
4755 | j = _idom[j]->_idx; |
4756 | } |
4757 | // Compute the depth on the way back down this tree branch |
4758 | uint dd = _dom_depth[j] + 1; |
4759 | while (_dom_stk->length() > 0) { |
4760 | uint j = _dom_stk->pop(); |
4761 | _dom_depth[j] = dd; |
4762 | dd++; |
4763 | } |
4764 | } |
4765 | } |
4766 | |
4767 | //------------------------------sort------------------------------------------- |
4768 | // Insert 'loop' into the existing loop tree. 'innermost' is a leaf of the |
4769 | // loop tree, not the root. |
4770 | IdealLoopTree *PhaseIdealLoop::sort( IdealLoopTree *loop, IdealLoopTree *innermost ) { |
4771 | if( !innermost ) return loop; // New innermost loop |
4772 | |
4773 | int loop_preorder = get_preorder(loop->_head); // Cache pre-order number |
4774 | assert( loop_preorder, "not yet post-walked loop" )do { if (!(loop_preorder)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4774, "assert(" "loop_preorder" ") failed", "not yet post-walked loop" ); ::breakpoint(); } } while (0); |
4775 | IdealLoopTree **pp = &innermost; // Pointer to previous next-pointer |
4776 | IdealLoopTree *l = *pp; // Do I go before or after 'l'? |
4777 | |
4778 | // Insert at start of list |
4779 | while( l ) { // Insertion sort based on pre-order |
4780 | if( l == loop ) return innermost; // Already on list! |
4781 | int l_preorder = get_preorder(l->_head); // Cache pre-order number |
4782 | assert( l_preorder, "not yet post-walked l" )do { if (!(l_preorder)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4782, "assert(" "l_preorder" ") failed", "not yet post-walked l" ); ::breakpoint(); } } while (0); |
4783 | // Check header pre-order number to figure proper nesting |
4784 | if( loop_preorder > l_preorder ) |
4785 | break; // End of insertion |
4786 | // If headers tie (e.g., shared headers) check tail pre-order numbers. |
4787 | // Since I split shared headers, you'd think this could not happen. |
4788 | // BUT: I must first do the preorder numbering before I can discover I |
4789 | // have shared headers, so the split headers all get the same preorder |
4790 | // number as the RegionNode they split from. |
4791 | if( loop_preorder == l_preorder && |
4792 | get_preorder(loop->_tail) < get_preorder(l->_tail) ) |
4793 | break; // Also check for shared headers (same pre#) |
4794 | pp = &l->_parent; // Chain up list |
4795 | l = *pp; |
4796 | } |
4797 | // Link into list |
4798 | // Point predecessor to me |
4799 | *pp = loop; |
4800 | // Point me to successor |
4801 | IdealLoopTree *p = loop->_parent; |
4802 | loop->_parent = l; // Point me to successor |
4803 | if( p ) sort( p, innermost ); // Insert my parents into list as well |
4804 | return innermost; |
4805 | } |
4806 | |
4807 | //------------------------------build_loop_tree-------------------------------- |
4808 | // I use a modified Vick/Tarjan algorithm. I need pre- and a post- visit |
4809 | // bits. The _nodes[] array is mapped by Node index and holds a NULL for |
4810 | // not-yet-pre-walked, pre-order # for pre-but-not-post-walked and holds the |
4811 | // tightest enclosing IdealLoopTree for post-walked. |
4812 | // |
4813 | // During my forward walk I do a short 1-layer lookahead to see if I can find |
4814 | // a loop backedge with that doesn't have any work on the backedge. This |
4815 | // helps me construct nested loops with shared headers better. |
4816 | // |
4817 | // Once I've done the forward recursion, I do the post-work. For each child |
4818 | // I check to see if there is a backedge. Backedges define a loop! I |
4819 | // insert an IdealLoopTree at the target of the backedge. |
4820 | // |
4821 | // During the post-work I also check to see if I have several children |
4822 | // belonging to different loops. If so, then this Node is a decision point |
4823 | // where control flow can choose to change loop nests. It is at this |
4824 | // decision point where I can figure out how loops are nested. At this |
4825 | // time I can properly order the different loop nests from my children. |
4826 | // Note that there may not be any backedges at the decision point! |
4827 | // |
4828 | // Since the decision point can be far removed from the backedges, I can't |
4829 | // order my loops at the time I discover them. Thus at the decision point |
4830 | // I need to inspect loop header pre-order numbers to properly nest my |
4831 | // loops. This means I need to sort my childrens' loops by pre-order. |
4832 | // The sort is of size number-of-control-children, which generally limits |
4833 | // it to size 2 (i.e., I just choose between my 2 target loops). |
4834 | void PhaseIdealLoop::build_loop_tree() { |
4835 | // Allocate stack of size C->live_nodes()/2 to avoid frequent realloc |
4836 | GrowableArray <Node *> bltstack(C->live_nodes() >> 1); |
4837 | Node *n = C->root(); |
4838 | bltstack.push(n); |
4839 | int pre_order = 1; |
4840 | int stack_size; |
4841 | |
4842 | while ( ( stack_size = bltstack.length() ) != 0 ) { |
4843 | n = bltstack.top(); // Leave node on stack |
4844 | if ( !is_visited(n) ) { |
4845 | // ---- Pre-pass Work ---- |
4846 | // Pre-walked but not post-walked nodes need a pre_order number. |
4847 | |
4848 | set_preorder_visited( n, pre_order ); // set as visited |
4849 | |
4850 | // ---- Scan over children ---- |
4851 | // Scan first over control projections that lead to loop headers. |
4852 | // This helps us find inner-to-outer loops with shared headers better. |
4853 | |
4854 | // Scan children's children for loop headers. |
4855 | for ( int i = n->outcnt() - 1; i >= 0; --i ) { |
4856 | Node* m = n->raw_out(i); // Child |
4857 | if( m->is_CFG() && !is_visited(m) ) { // Only for CFG children |
4858 | // Scan over children's children to find loop |
4859 | for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) { |
4860 | Node* l = m->fast_out(j); |
4861 | if( is_visited(l) && // Been visited? |
4862 | !is_postvisited(l) && // But not post-visited |
4863 | get_preorder(l) < pre_order ) { // And smaller pre-order |
4864 | // Found! Scan the DFS down this path before doing other paths |
4865 | bltstack.push(m); |
4866 | break; |
4867 | } |
4868 | } |
4869 | } |
4870 | } |
4871 | pre_order++; |
4872 | } |
4873 | else if ( !is_postvisited(n) ) { |
4874 | // Note: build_loop_tree_impl() adds out edges on rare occasions, |
4875 | // such as com.sun.rsasign.am::a. |
4876 | // For non-recursive version, first, process current children. |
4877 | // On next iteration, check if additional children were added. |
4878 | for ( int k = n->outcnt() - 1; k >= 0; --k ) { |
4879 | Node* u = n->raw_out(k); |
4880 | if ( u->is_CFG() && !is_visited(u) ) { |
4881 | bltstack.push(u); |
4882 | } |
4883 | } |
4884 | if ( bltstack.length() == stack_size ) { |
4885 | // There were no additional children, post visit node now |
4886 | (void)bltstack.pop(); // Remove node from stack |
4887 | pre_order = build_loop_tree_impl( n, pre_order ); |
4888 | // Check for bailout |
4889 | if (C->failing()) { |
4890 | return; |
4891 | } |
4892 | // Check to grow _preorders[] array for the case when |
4893 | // build_loop_tree_impl() adds new nodes. |
4894 | check_grow_preorders(); |
4895 | } |
4896 | } |
4897 | else { |
4898 | (void)bltstack.pop(); // Remove post-visited node from stack |
4899 | } |
4900 | } |
4901 | } |
4902 | |
4903 | //------------------------------build_loop_tree_impl--------------------------- |
4904 | int PhaseIdealLoop::build_loop_tree_impl( Node *n, int pre_order ) { |
4905 | // ---- Post-pass Work ---- |
4906 | // Pre-walked but not post-walked nodes need a pre_order number. |
4907 | |
4908 | // Tightest enclosing loop for this Node |
4909 | IdealLoopTree *innermost = NULL__null; |
4910 | |
4911 | // For all children, see if any edge is a backedge. If so, make a loop |
4912 | // for it. Then find the tightest enclosing loop for the self Node. |
4913 | for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { |
4914 | Node* m = n->fast_out(i); // Child |
4915 | if( n == m ) continue; // Ignore control self-cycles |
4916 | if( !m->is_CFG() ) continue;// Ignore non-CFG edges |
4917 | |
4918 | IdealLoopTree *l; // Child's loop |
4919 | if( !is_postvisited(m) ) { // Child visited but not post-visited? |
4920 | // Found a backedge |
4921 | assert( get_preorder(m) < pre_order, "should be backedge" )do { if (!(get_preorder(m) < pre_order)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4921, "assert(" "get_preorder(m) < pre_order" ") failed" , "should be backedge"); ::breakpoint(); } } while (0); |
4922 | // Check for the RootNode, which is already a LoopNode and is allowed |
4923 | // to have multiple "backedges". |
4924 | if( m == C->root()) { // Found the root? |
4925 | l = _ltree_root; // Root is the outermost LoopNode |
4926 | } else { // Else found a nested loop |
4927 | // Insert a LoopNode to mark this loop. |
4928 | l = new IdealLoopTree(this, m, n); |
4929 | } // End of Else found a nested loop |
4930 | if( !has_loop(m) ) // If 'm' does not already have a loop set |
4931 | set_loop(m, l); // Set loop header to loop now |
4932 | |
4933 | } else { // Else not a nested loop |
4934 | if( !_nodes[m->_idx] ) continue; // Dead code has no loop |
4935 | l = get_loop(m); // Get previously determined loop |
4936 | // If successor is header of a loop (nest), move up-loop till it |
4937 | // is a member of some outer enclosing loop. Since there are no |
4938 | // shared headers (I've split them already) I only need to go up |
4939 | // at most 1 level. |
4940 | while( l && l->_head == m ) // Successor heads loop? |
4941 | l = l->_parent; // Move up 1 for me |
4942 | // If this loop is not properly parented, then this loop |
4943 | // has no exit path out, i.e. its an infinite loop. |
4944 | if( !l ) { |
4945 | // Make loop "reachable" from root so the CFG is reachable. Basically |
4946 | // insert a bogus loop exit that is never taken. 'm', the loop head, |
4947 | // points to 'n', one (of possibly many) fall-in paths. There may be |
4948 | // many backedges as well. |
4949 | |
4950 | // Here I set the loop to be the root loop. I could have, after |
4951 | // inserting a bogus loop exit, restarted the recursion and found my |
4952 | // new loop exit. This would make the infinite loop a first-class |
4953 | // loop and it would then get properly optimized. What's the use of |
4954 | // optimizing an infinite loop? |
4955 | l = _ltree_root; // Oops, found infinite loop |
4956 | |
4957 | if (!_verify_only) { |
4958 | // Insert the NeverBranch between 'm' and it's control user. |
4959 | NeverBranchNode *iff = new NeverBranchNode( m ); |
4960 | _igvn.register_new_node_with_optimizer(iff); |
4961 | set_loop(iff, l); |
4962 | Node *if_t = new CProjNode( iff, 0 ); |
4963 | _igvn.register_new_node_with_optimizer(if_t); |
4964 | set_loop(if_t, l); |
4965 | |
4966 | Node* cfg = NULL__null; // Find the One True Control User of m |
4967 | for (DUIterator_Fast jmax, j = m->fast_outs(jmax); j < jmax; j++) { |
4968 | Node* x = m->fast_out(j); |
4969 | if (x->is_CFG() && x != m && x != iff) |
4970 | { cfg = x; break; } |
4971 | } |
4972 | assert(cfg != NULL, "must find the control user of m")do { if (!(cfg != __null)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 4972, "assert(" "cfg != __null" ") failed", "must find the control user of m" ); ::breakpoint(); } } while (0); |
4973 | uint k = 0; // Probably cfg->in(0) |
4974 | while( cfg->in(k) != m ) k++; // But check incase cfg is a Region |
4975 | cfg->set_req( k, if_t ); // Now point to NeverBranch |
4976 | _igvn._worklist.push(cfg); |
4977 | |
4978 | // Now create the never-taken loop exit |
4979 | Node *if_f = new CProjNode( iff, 1 ); |
4980 | _igvn.register_new_node_with_optimizer(if_f); |
4981 | set_loop(if_f, l); |
4982 | // Find frame ptr for Halt. Relies on the optimizer |
4983 | // V-N'ing. Easier and quicker than searching through |
4984 | // the program structure. |
4985 | Node *frame = new ParmNode( C->start(), TypeFunc::FramePtr ); |
4986 | _igvn.register_new_node_with_optimizer(frame); |
4987 | // Halt & Catch Fire |
4988 | Node* halt = new HaltNode(if_f, frame, "never-taken loop exit reached"); |
4989 | _igvn.register_new_node_with_optimizer(halt); |
4990 | set_loop(halt, l); |
4991 | C->root()->add_req(halt); |
4992 | } |
4993 | set_loop(C->root(), _ltree_root); |
4994 | } |
4995 | } |
4996 | // Weeny check for irreducible. This child was already visited (this |
4997 | // IS the post-work phase). Is this child's loop header post-visited |
4998 | // as well? If so, then I found another entry into the loop. |
4999 | if (!_verify_only) { |
5000 | while( is_postvisited(l->_head) ) { |
5001 | // found irreducible |
5002 | l->_irreducible = 1; // = true |
5003 | l = l->_parent; |
5004 | _has_irreducible_loops = true; |
5005 | // Check for bad CFG here to prevent crash, and bailout of compile |
5006 | if (l == NULL__null) { |
5007 | C->record_method_not_compilable("unhandled CFG detected during loop optimization"); |
5008 | return pre_order; |
5009 | } |
5010 | } |
5011 | C->set_has_irreducible_loop(_has_irreducible_loops); |
5012 | } |
5013 | |
5014 | // This Node might be a decision point for loops. It is only if |
5015 | // it's children belong to several different loops. The sort call |
5016 | // does a trivial amount of work if there is only 1 child or all |
5017 | // children belong to the same loop. If however, the children |
5018 | // belong to different loops, the sort call will properly set the |
5019 | // _parent pointers to show how the loops nest. |
5020 | // |
5021 | // In any case, it returns the tightest enclosing loop. |
5022 | innermost = sort( l, innermost ); |
5023 | } |
5024 | |
5025 | // Def-use info will have some dead stuff; dead stuff will have no |
5026 | // loop decided on. |
5027 | |
5028 | // Am I a loop header? If so fix up my parent's child and next ptrs. |
5029 | if( innermost && innermost->_head == n ) { |
5030 | assert( get_loop(n) == innermost, "" )do { if (!(get_loop(n) == innermost)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5030, "assert(" "get_loop(n) == innermost" ") failed", ""); ::breakpoint(); } } while (0); |
5031 | IdealLoopTree *p = innermost->_parent; |
5032 | IdealLoopTree *l = innermost; |
5033 | while( p && l->_head == n ) { |
5034 | l->_next = p->_child; // Put self on parents 'next child' |
5035 | p->_child = l; // Make self as first child of parent |
5036 | l = p; // Now walk up the parent chain |
5037 | p = l->_parent; |
5038 | } |
5039 | } else { |
5040 | // Note that it is possible for a LoopNode to reach here, if the |
5041 | // backedge has been made unreachable (hence the LoopNode no longer |
5042 | // denotes a Loop, and will eventually be removed). |
5043 | |
5044 | // Record tightest enclosing loop for self. Mark as post-visited. |
5045 | set_loop(n, innermost); |
5046 | // Also record has_call flag early on |
5047 | if( innermost ) { |
5048 | if( n->is_Call() && !n->is_CallLeaf() && !n->is_macro() ) { |
5049 | // Do not count uncommon calls |
5050 | if( !n->is_CallStaticJava() || !n->as_CallStaticJava()->_name ) { |
5051 | Node *iff = n->in(0)->in(0); |
5052 | // No any calls for vectorized loops. |
5053 | if( UseSuperWord || !iff->is_If() || |
5054 | (n->in(0)->Opcode() == Op_IfFalse && |
5055 | (1.0 - iff->as_If()->_prob) >= 0.01) || |
5056 | (iff->as_If()->_prob >= 0.01) ) |
5057 | innermost->_has_call = 1; |
5058 | } |
5059 | } else if( n->is_Allocate() && n->as_Allocate()->_is_scalar_replaceable ) { |
5060 | // Disable loop optimizations if the loop has a scalar replaceable |
5061 | // allocation. This disabling may cause a potential performance lost |
5062 | // if the allocation is not eliminated for some reason. |
5063 | innermost->_allow_optimizations = false; |
5064 | innermost->_has_call = 1; // = true |
5065 | } else if (n->Opcode() == Op_SafePoint) { |
5066 | // Record all safepoints in this loop. |
5067 | if (innermost->_safepts == NULL__null) innermost->_safepts = new Node_List(); |
5068 | innermost->_safepts->push(n); |
5069 | } |
5070 | } |
5071 | } |
5072 | |
5073 | // Flag as post-visited now |
5074 | set_postvisited(n); |
5075 | return pre_order; |
5076 | } |
5077 | |
5078 | |
5079 | //------------------------------build_loop_early------------------------------- |
5080 | // Put Data nodes into some loop nest, by setting the _nodes[]->loop mapping. |
5081 | // First pass computes the earliest controlling node possible. This is the |
5082 | // controlling input with the deepest dominating depth. |
5083 | void PhaseIdealLoop::build_loop_early( VectorSet &visited, Node_List &worklist, Node_Stack &nstack ) { |
5084 | while (worklist.size() != 0) { |
5085 | // Use local variables nstack_top_n & nstack_top_i to cache values |
5086 | // on nstack's top. |
5087 | Node *nstack_top_n = worklist.pop(); |
5088 | uint nstack_top_i = 0; |
5089 | //while_nstack_nonempty: |
5090 | while (true) { |
5091 | // Get parent node and next input's index from stack's top. |
5092 | Node *n = nstack_top_n; |
5093 | uint i = nstack_top_i; |
5094 | uint cnt = n->req(); // Count of inputs |
5095 | if (i == 0) { // Pre-process the node. |
5096 | if( has_node(n) && // Have either loop or control already? |
5097 | !has_ctrl(n) ) { // Have loop picked out already? |
5098 | // During "merge_many_backedges" we fold up several nested loops |
5099 | // into a single loop. This makes the members of the original |
5100 | // loop bodies pointing to dead loops; they need to move up |
5101 | // to the new UNION'd larger loop. I set the _head field of these |
5102 | // dead loops to NULL and the _parent field points to the owning |
5103 | // loop. Shades of UNION-FIND algorithm. |
5104 | IdealLoopTree *ilt; |
5105 | while( !(ilt = get_loop(n))->_head ) { |
5106 | // Normally I would use a set_loop here. But in this one special |
5107 | // case, it is legal (and expected) to change what loop a Node |
5108 | // belongs to. |
5109 | _nodes.map(n->_idx, (Node*)(ilt->_parent) ); |
5110 | } |
5111 | // Remove safepoints ONLY if I've already seen I don't need one. |
5112 | // (the old code here would yank a 2nd safepoint after seeing a |
5113 | // first one, even though the 1st did not dominate in the loop body |
5114 | // and thus could be avoided indefinitely) |
5115 | if( !_verify_only && !_verify_me && ilt->_has_sfpt && n->Opcode() == Op_SafePoint && |
5116 | is_deleteable_safept(n)) { |
5117 | Node *in = n->in(TypeFunc::Control); |
5118 | lazy_replace(n,in); // Pull safepoint now |
5119 | if (ilt->_safepts != NULL__null) { |
5120 | ilt->_safepts->yank(n); |
5121 | } |
5122 | // Carry on with the recursion "as if" we are walking |
5123 | // only the control input |
5124 | if( !visited.test_set( in->_idx ) ) { |
5125 | worklist.push(in); // Visit this guy later, using worklist |
5126 | } |
5127 | // Get next node from nstack: |
5128 | // - skip n's inputs processing by setting i > cnt; |
5129 | // - we also will not call set_early_ctrl(n) since |
5130 | // has_node(n) == true (see the condition above). |
5131 | i = cnt + 1; |
5132 | } |
5133 | } |
5134 | } // if (i == 0) |
5135 | |
5136 | // Visit all inputs |
5137 | bool done = true; // Assume all n's inputs will be processed |
5138 | while (i < cnt) { |
5139 | Node *in = n->in(i); |
5140 | ++i; |
5141 | if (in == NULL__null) continue; |
5142 | if (in->pinned() && !in->is_CFG()) |
5143 | set_ctrl(in, in->in(0)); |
5144 | int is_visited = visited.test_set( in->_idx ); |
5145 | if (!has_node(in)) { // No controlling input yet? |
5146 | assert( !in->is_CFG(), "CFG Node with no controlling input?" )do { if (!(!in->is_CFG())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5146, "assert(" "!in->is_CFG()" ") failed", "CFG Node with no controlling input?" ); ::breakpoint(); } } while (0); |
5147 | assert( !is_visited, "visit only once" )do { if (!(!is_visited)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5147, "assert(" "!is_visited" ") failed", "visit only once" ); ::breakpoint(); } } while (0); |
5148 | nstack.push(n, i); // Save parent node and next input's index. |
5149 | nstack_top_n = in; // Process current input now. |
5150 | nstack_top_i = 0; |
5151 | done = false; // Not all n's inputs processed. |
5152 | break; // continue while_nstack_nonempty; |
5153 | } else if (!is_visited) { |
5154 | // This guy has a location picked out for him, but has not yet |
5155 | // been visited. Happens to all CFG nodes, for instance. |
5156 | // Visit him using the worklist instead of recursion, to break |
5157 | // cycles. Since he has a location already we do not need to |
5158 | // find his location before proceeding with the current Node. |
5159 | worklist.push(in); // Visit this guy later, using worklist |
5160 | } |
5161 | } |
5162 | if (done) { |
5163 | // All of n's inputs have been processed, complete post-processing. |
5164 | |
5165 | // Compute earliest point this Node can go. |
5166 | // CFG, Phi, pinned nodes already know their controlling input. |
5167 | if (!has_node(n)) { |
5168 | // Record earliest legal location |
5169 | set_early_ctrl(n, false); |
5170 | } |
5171 | if (nstack.is_empty()) { |
5172 | // Finished all nodes on stack. |
5173 | // Process next node on the worklist. |
5174 | break; |
5175 | } |
5176 | // Get saved parent node and next input's index. |
5177 | nstack_top_n = nstack.node(); |
5178 | nstack_top_i = nstack.index(); |
5179 | nstack.pop(); |
5180 | } |
5181 | } // while (true) |
5182 | } |
5183 | } |
5184 | |
5185 | //------------------------------dom_lca_internal-------------------------------- |
5186 | // Pair-wise LCA |
5187 | Node *PhaseIdealLoop::dom_lca_internal( Node *n1, Node *n2 ) const { |
5188 | if( !n1 ) return n2; // Handle NULL original LCA |
5189 | assert( n1->is_CFG(), "" )do { if (!(n1->is_CFG())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5189, "assert(" "n1->is_CFG()" ") failed", ""); ::breakpoint (); } } while (0); |
5190 | assert( n2->is_CFG(), "" )do { if (!(n2->is_CFG())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5190, "assert(" "n2->is_CFG()" ") failed", ""); ::breakpoint (); } } while (0); |
5191 | // find LCA of all uses |
5192 | uint d1 = dom_depth(n1); |
5193 | uint d2 = dom_depth(n2); |
5194 | while (n1 != n2) { |
5195 | if (d1 > d2) { |
5196 | n1 = idom(n1); |
5197 | d1 = dom_depth(n1); |
5198 | } else if (d1 < d2) { |
5199 | n2 = idom(n2); |
5200 | d2 = dom_depth(n2); |
5201 | } else { |
5202 | // Here d1 == d2. Due to edits of the dominator-tree, sections |
5203 | // of the tree might have the same depth. These sections have |
5204 | // to be searched more carefully. |
5205 | |
5206 | // Scan up all the n1's with equal depth, looking for n2. |
5207 | Node *t1 = idom(n1); |
5208 | while (dom_depth(t1) == d1) { |
5209 | if (t1 == n2) return n2; |
5210 | t1 = idom(t1); |
5211 | } |
5212 | // Scan up all the n2's with equal depth, looking for n1. |
5213 | Node *t2 = idom(n2); |
5214 | while (dom_depth(t2) == d2) { |
5215 | if (t2 == n1) return n1; |
5216 | t2 = idom(t2); |
5217 | } |
5218 | // Move up to a new dominator-depth value as well as up the dom-tree. |
5219 | n1 = t1; |
5220 | n2 = t2; |
5221 | d1 = dom_depth(n1); |
5222 | d2 = dom_depth(n2); |
5223 | } |
5224 | } |
5225 | return n1; |
5226 | } |
5227 | |
5228 | //------------------------------compute_idom----------------------------------- |
5229 | // Locally compute IDOM using dom_lca call. Correct only if the incoming |
5230 | // IDOMs are correct. |
5231 | Node *PhaseIdealLoop::compute_idom( Node *region ) const { |
5232 | assert( region->is_Region(), "" )do { if (!(region->is_Region())) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5232, "assert(" "region->is_Region()" ") failed", ""); :: breakpoint(); } } while (0); |
5233 | Node *LCA = NULL__null; |
5234 | for( uint i = 1; i < region->req(); i++ ) { |
5235 | if( region->in(i) != C->top() ) |
5236 | LCA = dom_lca( LCA, region->in(i) ); |
5237 | } |
5238 | return LCA; |
5239 | } |
5240 | |
5241 | bool PhaseIdealLoop::verify_dominance(Node* n, Node* use, Node* LCA, Node* early) { |
5242 | bool had_error = false; |
5243 | #ifdef ASSERT1 |
5244 | if (early != C->root()) { |
5245 | // Make sure that there's a dominance path from LCA to early |
5246 | Node* d = LCA; |
5247 | while (d != early) { |
5248 | if (d == C->root()) { |
5249 | dump_bad_graph("Bad graph detected in compute_lca_of_uses", n, early, LCA); |
5250 | tty->print_cr("*** Use %d isn't dominated by def %d ***", use->_idx, n->_idx); |
5251 | had_error = true; |
5252 | break; |
5253 | } |
5254 | d = idom(d); |
5255 | } |
5256 | } |
5257 | #endif |
5258 | return had_error; |
5259 | } |
5260 | |
5261 | |
5262 | Node* PhaseIdealLoop::compute_lca_of_uses(Node* n, Node* early, bool verify) { |
5263 | // Compute LCA over list of uses |
5264 | bool had_error = false; |
5265 | Node *LCA = NULL__null; |
5266 | for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax && LCA != early; i++) { |
5267 | Node* c = n->fast_out(i); |
5268 | if (_nodes[c->_idx] == NULL__null) |
5269 | continue; // Skip the occasional dead node |
5270 | if( c->is_Phi() ) { // For Phis, we must land above on the path |
5271 | for( uint j=1; j<c->req(); j++ ) {// For all inputs |
5272 | if( c->in(j) == n ) { // Found matching input? |
5273 | Node *use = c->in(0)->in(j); |
5274 | if (_verify_only && use->is_top()) continue; |
5275 | LCA = dom_lca_for_get_late_ctrl( LCA, use, n ); |
5276 | if (verify) had_error = verify_dominance(n, use, LCA, early) || had_error; |
5277 | } |
5278 | } |
5279 | } else { |
5280 | // For CFG data-users, use is in the block just prior |
5281 | Node *use = has_ctrl(c) ? get_ctrl(c) : c->in(0); |
5282 | LCA = dom_lca_for_get_late_ctrl( LCA, use, n ); |
5283 | if (verify) had_error = verify_dominance(n, use, LCA, early) || had_error; |
5284 | } |
5285 | } |
5286 | assert(!had_error, "bad dominance")do { if (!(!had_error)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5286, "assert(" "!had_error" ") failed", "bad dominance"); :: breakpoint(); } } while (0); |
5287 | return LCA; |
5288 | } |
5289 | |
5290 | // Check the shape of the graph at the loop entry. In some cases, |
5291 | // the shape of the graph does not match the shape outlined below. |
5292 | // That is caused by the Opaque1 node "protecting" the shape of |
5293 | // the graph being removed by, for example, the IGVN performed |
5294 | // in PhaseIdealLoop::build_and_optimize(). |
5295 | // |
5296 | // After the Opaque1 node has been removed, optimizations (e.g., split-if, |
5297 | // loop unswitching, and IGVN, or a combination of them) can freely change |
5298 | // the graph's shape. As a result, the graph shape outlined below cannot |
5299 | // be guaranteed anymore. |
5300 | Node* CountedLoopNode::is_canonical_loop_entry() { |
5301 | if (!is_main_loop() && !is_post_loop()) { |
5302 | return NULL__null; |
5303 | } |
5304 | Node* ctrl = skip_predicates(); |
5305 | |
5306 | if (ctrl == NULL__null || (!ctrl->is_IfTrue() && !ctrl->is_IfFalse())) { |
5307 | return NULL__null; |
5308 | } |
5309 | Node* iffm = ctrl->in(0); |
5310 | if (iffm == NULL__null || !iffm->is_If()) { |
5311 | return NULL__null; |
5312 | } |
5313 | Node* bolzm = iffm->in(1); |
5314 | if (bolzm == NULL__null || !bolzm->is_Bool()) { |
5315 | return NULL__null; |
5316 | } |
5317 | Node* cmpzm = bolzm->in(1); |
5318 | if (cmpzm == NULL__null || !cmpzm->is_Cmp()) { |
5319 | return NULL__null; |
5320 | } |
5321 | |
5322 | uint input = is_main_loop() ? 2 : 1; |
5323 | if (input >= cmpzm->req() || cmpzm->in(input) == NULL__null) { |
5324 | return NULL__null; |
5325 | } |
5326 | bool res = cmpzm->in(input)->Opcode() == Op_Opaque1; |
5327 | #ifdef ASSERT1 |
5328 | bool found_opaque = false; |
5329 | for (uint i = 1; i < cmpzm->req(); i++) { |
5330 | Node* opnd = cmpzm->in(i); |
5331 | if (opnd && opnd->Opcode() == Op_Opaque1) { |
5332 | found_opaque = true; |
5333 | break; |
5334 | } |
5335 | } |
5336 | assert(found_opaque == res, "wrong pattern")do { if (!(found_opaque == res)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5336, "assert(" "found_opaque == res" ") failed", "wrong pattern" ); ::breakpoint(); } } while (0); |
5337 | #endif |
5338 | return res ? cmpzm->in(input) : NULL__null; |
5339 | } |
5340 | |
5341 | //------------------------------get_late_ctrl---------------------------------- |
5342 | // Compute latest legal control. |
5343 | Node *PhaseIdealLoop::get_late_ctrl( Node *n, Node *early ) { |
5344 | assert(early != NULL, "early control should not be NULL")do { if (!(early != __null)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5344, "assert(" "early != __null" ") failed", "early control should not be NULL" ); ::breakpoint(); } } while (0); |
5345 | |
5346 | Node* LCA = compute_lca_of_uses(n, early); |
5347 | #ifdef ASSERT1 |
5348 | if (LCA == C->root() && LCA != early) { |
5349 | // def doesn't dominate uses so print some useful debugging output |
5350 | compute_lca_of_uses(n, early, true); |
5351 | } |
5352 | #endif |
5353 | |
5354 | if (n->is_Load() && LCA != early) { |
5355 | LCA = get_late_ctrl_with_anti_dep(n->as_Load(), early, LCA); |
5356 | } |
5357 | |
5358 | assert(LCA == find_non_split_ctrl(LCA), "unexpected late control")do { if (!(LCA == find_non_split_ctrl(LCA))) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5358, "assert(" "LCA == find_non_split_ctrl(LCA)" ") failed" , "unexpected late control"); ::breakpoint(); } } while (0); |
5359 | return LCA; |
5360 | } |
5361 | |
5362 | // if this is a load, check for anti-dependent stores |
5363 | // We use a conservative algorithm to identify potential interfering |
5364 | // instructions and for rescheduling the load. The users of the memory |
5365 | // input of this load are examined. Any use which is not a load and is |
5366 | // dominated by early is considered a potentially interfering store. |
5367 | // This can produce false positives. |
5368 | Node* PhaseIdealLoop::get_late_ctrl_with_anti_dep(LoadNode* n, Node* early, Node* LCA) { |
5369 | int load_alias_idx = C->get_alias_index(n->adr_type()); |
5370 | if (C->alias_type(load_alias_idx)->is_rewritable()) { |
5371 | Unique_Node_List worklist; |
5372 | |
5373 | Node* mem = n->in(MemNode::Memory); |
5374 | for (DUIterator_Fast imax, i = mem->fast_outs(imax); i < imax; i++) { |
5375 | Node* s = mem->fast_out(i); |
5376 | worklist.push(s); |
5377 | } |
5378 | for (uint i = 0; i < worklist.size() && LCA != early; i++) { |
5379 | Node* s = worklist.at(i); |
5380 | if (s->is_Load() || s->Opcode() == Op_SafePoint || |
5381 | (s->is_CallStaticJava() && s->as_CallStaticJava()->uncommon_trap_request() != 0) || |
5382 | s->is_Phi()) { |
5383 | continue; |
5384 | } else if (s->is_MergeMem()) { |
5385 | for (DUIterator_Fast imax, i = s->fast_outs(imax); i < imax; i++) { |
5386 | Node* s1 = s->fast_out(i); |
5387 | worklist.push(s1); |
5388 | } |
5389 | } else { |
5390 | Node* sctrl = has_ctrl(s) ? get_ctrl(s) : s->in(0); |
5391 | assert(sctrl != NULL || !s->is_reachable_from_root(), "must have control")do { if (!(sctrl != __null || !s->is_reachable_from_root() )) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5391, "assert(" "sctrl != __null || !s->is_reachable_from_root()" ") failed", "must have control"); ::breakpoint(); } } while ( 0); |
5392 | if (sctrl != NULL__null && !sctrl->is_top() && is_dominator(early, sctrl)) { |
5393 | const TypePtr* adr_type = s->adr_type(); |
5394 | if (s->is_ArrayCopy()) { |
5395 | // Copy to known instance needs destination type to test for aliasing |
5396 | const TypePtr* dest_type = s->as_ArrayCopy()->_dest_type; |
5397 | if (dest_type != TypeOopPtr::BOTTOM) { |
5398 | adr_type = dest_type; |
5399 | } |
5400 | } |
5401 | if (C->can_alias(adr_type, load_alias_idx)) { |
5402 | LCA = dom_lca_for_get_late_ctrl(LCA, sctrl, n); |
5403 | } else if (s->is_CFG() && s->is_Multi()) { |
5404 | // Look for the memory use of s (that is the use of its memory projection) |
5405 | for (DUIterator_Fast imax, i = s->fast_outs(imax); i < imax; i++) { |
5406 | Node* s1 = s->fast_out(i); |
5407 | assert(s1->is_Proj(), "projection expected")do { if (!(s1->is_Proj())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5407, "assert(" "s1->is_Proj()" ") failed", "projection expected" ); ::breakpoint(); } } while (0); |
5408 | if (_igvn.type(s1) == Type::MEMORY) { |
5409 | for (DUIterator_Fast jmax, j = s1->fast_outs(jmax); j < jmax; j++) { |
5410 | Node* s2 = s1->fast_out(j); |
5411 | worklist.push(s2); |
5412 | } |
5413 | } |
5414 | } |
5415 | } |
5416 | } |
5417 | } |
5418 | } |
5419 | // For Phis only consider Region's inputs that were reached by following the memory edges |
5420 | if (LCA != early) { |
5421 | for (uint i = 0; i < worklist.size(); i++) { |
5422 | Node* s = worklist.at(i); |
5423 | if (s->is_Phi() && C->can_alias(s->adr_type(), load_alias_idx)) { |
5424 | Node* r = s->in(0); |
5425 | for (uint j = 1; j < s->req(); j++) { |
5426 | Node* in = s->in(j); |
5427 | Node* r_in = r->in(j); |
5428 | // We can't reach any node from a Phi because we don't enqueue Phi's uses above |
5429 | if (((worklist.member(in) && !in->is_Phi()) || in == mem) && is_dominator(early, r_in)) { |
5430 | LCA = dom_lca_for_get_late_ctrl(LCA, r_in, n); |
5431 | } |
5432 | } |
5433 | } |
5434 | } |
5435 | } |
5436 | } |
5437 | return LCA; |
5438 | } |
5439 | |
5440 | // true if CFG node d dominates CFG node n |
5441 | bool PhaseIdealLoop::is_dominator(Node *d, Node *n) { |
5442 | if (d == n) |
5443 | return true; |
5444 | assert(d->is_CFG() && n->is_CFG(), "must have CFG nodes")do { if (!(d->is_CFG() && n->is_CFG())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5444, "assert(" "d->is_CFG() && n->is_CFG()" ") failed" , "must have CFG nodes"); ::breakpoint(); } } while (0); |
5445 | uint dd = dom_depth(d); |
5446 | while (dom_depth(n) >= dd) { |
5447 | if (n == d) |
5448 | return true; |
5449 | n = idom(n); |
5450 | } |
5451 | return false; |
5452 | } |
5453 | |
5454 | //------------------------------dom_lca_for_get_late_ctrl_internal------------- |
5455 | // Pair-wise LCA with tags. |
5456 | // Tag each index with the node 'tag' currently being processed |
5457 | // before advancing up the dominator chain using idom(). |
5458 | // Later calls that find a match to 'tag' know that this path has already |
5459 | // been considered in the current LCA (which is input 'n1' by convention). |
5460 | // Since get_late_ctrl() is only called once for each node, the tag array |
5461 | // does not need to be cleared between calls to get_late_ctrl(). |
5462 | // Algorithm trades a larger constant factor for better asymptotic behavior |
5463 | // |
5464 | Node *PhaseIdealLoop::dom_lca_for_get_late_ctrl_internal(Node *n1, Node *n2, Node *tag_node) { |
5465 | uint d1 = dom_depth(n1); |
5466 | uint d2 = dom_depth(n2); |
5467 | jlong tag = tag_node->_idx | (((jlong)_dom_lca_tags_round) << 32); |
5468 | |
5469 | do { |
5470 | if (d1 > d2) { |
5471 | // current lca is deeper than n2 |
5472 | _dom_lca_tags.at_put_grow(n1->_idx, tag); |
5473 | n1 = idom(n1); |
5474 | d1 = dom_depth(n1); |
5475 | } else if (d1 < d2) { |
5476 | // n2 is deeper than current lca |
5477 | jlong memo = _dom_lca_tags.at_grow(n2->_idx, 0); |
5478 | if (memo == tag) { |
5479 | return n1; // Return the current LCA |
5480 | } |
5481 | _dom_lca_tags.at_put_grow(n2->_idx, tag); |
5482 | n2 = idom(n2); |
5483 | d2 = dom_depth(n2); |
5484 | } else { |
5485 | // Here d1 == d2. Due to edits of the dominator-tree, sections |
5486 | // of the tree might have the same depth. These sections have |
5487 | // to be searched more carefully. |
5488 | |
5489 | // Scan up all the n1's with equal depth, looking for n2. |
5490 | _dom_lca_tags.at_put_grow(n1->_idx, tag); |
5491 | Node *t1 = idom(n1); |
5492 | while (dom_depth(t1) == d1) { |
5493 | if (t1 == n2) return n2; |
5494 | _dom_lca_tags.at_put_grow(t1->_idx, tag); |
5495 | t1 = idom(t1); |
5496 | } |
5497 | // Scan up all the n2's with equal depth, looking for n1. |
5498 | _dom_lca_tags.at_put_grow(n2->_idx, tag); |
5499 | Node *t2 = idom(n2); |
5500 | while (dom_depth(t2) == d2) { |
5501 | if (t2 == n1) return n1; |
5502 | _dom_lca_tags.at_put_grow(t2->_idx, tag); |
5503 | t2 = idom(t2); |
5504 | } |
5505 | // Move up to a new dominator-depth value as well as up the dom-tree. |
5506 | n1 = t1; |
5507 | n2 = t2; |
5508 | d1 = dom_depth(n1); |
5509 | d2 = dom_depth(n2); |
5510 | } |
5511 | } while (n1 != n2); |
5512 | return n1; |
5513 | } |
5514 | |
5515 | //------------------------------init_dom_lca_tags------------------------------ |
5516 | // Tag could be a node's integer index, 32bits instead of 64bits in some cases |
5517 | // Intended use does not involve any growth for the array, so it could |
5518 | // be of fixed size. |
5519 | void PhaseIdealLoop::init_dom_lca_tags() { |
5520 | uint limit = C->unique() + 1; |
5521 | _dom_lca_tags.at_grow(limit, 0); |
5522 | _dom_lca_tags_round = 0; |
5523 | #ifdef ASSERT1 |
5524 | for (uint i = 0; i < limit; ++i) { |
5525 | assert(_dom_lca_tags.at(i) == 0, "Must be distinct from each node pointer")do { if (!(_dom_lca_tags.at(i) == 0)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5525, "assert(" "_dom_lca_tags.at(i) == 0" ") failed", "Must be distinct from each node pointer" ); ::breakpoint(); } } while (0); |
5526 | } |
5527 | #endif // ASSERT |
5528 | } |
5529 | |
5530 | //------------------------------build_loop_late-------------------------------- |
5531 | // Put Data nodes into some loop nest, by setting the _nodes[]->loop mapping. |
5532 | // Second pass finds latest legal placement, and ideal loop placement. |
5533 | void PhaseIdealLoop::build_loop_late( VectorSet &visited, Node_List &worklist, Node_Stack &nstack ) { |
5534 | while (worklist.size() != 0) { |
5535 | Node *n = worklist.pop(); |
5536 | // Only visit once |
5537 | if (visited.test_set(n->_idx)) continue; |
5538 | uint cnt = n->outcnt(); |
5539 | uint i = 0; |
5540 | while (true) { |
5541 | assert( _nodes[n->_idx], "no dead nodes" )do { if (!(_nodes[n->_idx])) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5541, "assert(" "_nodes[n->_idx]" ") failed", "no dead nodes" ); ::breakpoint(); } } while (0); |
5542 | // Visit all children |
5543 | if (i < cnt) { |
5544 | Node* use = n->raw_out(i); |
5545 | ++i; |
5546 | // Check for dead uses. Aggressively prune such junk. It might be |
5547 | // dead in the global sense, but still have local uses so I cannot |
5548 | // easily call 'remove_dead_node'. |
5549 | if( _nodes[use->_idx] != NULL__null || use->is_top() ) { // Not dead? |
5550 | // Due to cycles, we might not hit the same fixed point in the verify |
5551 | // pass as we do in the regular pass. Instead, visit such phis as |
5552 | // simple uses of the loop head. |
5553 | if( use->in(0) && (use->is_CFG() || use->is_Phi()) ) { |
5554 | if( !visited.test(use->_idx) ) |
5555 | worklist.push(use); |
5556 | } else if( !visited.test_set(use->_idx) ) { |
5557 | nstack.push(n, i); // Save parent and next use's index. |
5558 | n = use; // Process all children of current use. |
5559 | cnt = use->outcnt(); |
5560 | i = 0; |
5561 | } |
5562 | } else { |
5563 | // Do not visit around the backedge of loops via data edges. |
5564 | // push dead code onto a worklist |
5565 | _deadlist.push(use); |
5566 | } |
5567 | } else { |
5568 | // All of n's children have been processed, complete post-processing. |
5569 | build_loop_late_post(n); |
5570 | if (nstack.is_empty()) { |
5571 | // Finished all nodes on stack. |
5572 | // Process next node on the worklist. |
5573 | break; |
5574 | } |
5575 | // Get saved parent node and next use's index. Visit the rest of uses. |
5576 | n = nstack.node(); |
5577 | cnt = n->outcnt(); |
5578 | i = nstack.index(); |
5579 | nstack.pop(); |
5580 | } |
5581 | } |
5582 | } |
5583 | } |
5584 | |
5585 | // Verify that no data node is scheduled in the outer loop of a strip |
5586 | // mined loop. |
5587 | void PhaseIdealLoop::verify_strip_mined_scheduling(Node *n, Node* least) { |
5588 | #ifdef ASSERT1 |
5589 | if (get_loop(least)->_nest == 0) { |
5590 | return; |
5591 | } |
5592 | IdealLoopTree* loop = get_loop(least); |
5593 | Node* head = loop->_head; |
5594 | if (head->is_OuterStripMinedLoop() && |
5595 | // Verification can't be applied to fully built strip mined loops |
5596 | head->as_Loop()->outer_loop_end()->in(1)->find_int_con(-1) == 0) { |
5597 | Node* sfpt = head->as_Loop()->outer_safepoint(); |
5598 | ResourceMark rm; |
5599 | Unique_Node_List wq; |
5600 | wq.push(sfpt); |
5601 | for (uint i = 0; i < wq.size(); i++) { |
5602 | Node *m = wq.at(i); |
5603 | for (uint i = 1; i < m->req(); i++) { |
5604 | Node* nn = m->in(i); |
5605 | if (nn == n) { |
5606 | return; |
5607 | } |
5608 | if (nn != NULL__null && has_ctrl(nn) && get_loop(get_ctrl(nn)) == loop) { |
5609 | wq.push(nn); |
5610 | } |
5611 | } |
5612 | } |
5613 | ShouldNotReachHere()do { (*g_assert_poison) = 'X';; report_should_not_reach_here( "/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5613); ::breakpoint(); } while (0); |
5614 | } |
5615 | #endif |
5616 | } |
5617 | |
5618 | |
5619 | //------------------------------build_loop_late_post--------------------------- |
5620 | // Put Data nodes into some loop nest, by setting the _nodes[]->loop mapping. |
5621 | // Second pass finds latest legal placement, and ideal loop placement. |
5622 | void PhaseIdealLoop::build_loop_late_post(Node *n) { |
5623 | build_loop_late_post_work(n, true); |
5624 | } |
5625 | |
5626 | void PhaseIdealLoop::build_loop_late_post_work(Node *n, bool pinned) { |
5627 | |
5628 | if (n->req() == 2 && (n->Opcode() == Op_ConvI2L || n->Opcode() == Op_CastII) && !C->major_progress() && !_verify_only) { |
5629 | _igvn._worklist.push(n); // Maybe we'll normalize it, if no more loops. |
5630 | } |
5631 | |
5632 | #ifdef ASSERT1 |
5633 | if (_verify_only && !n->is_CFG()) { |
5634 | // Check def-use domination. |
5635 | compute_lca_of_uses(n, get_ctrl(n), true /* verify */); |
5636 | } |
5637 | #endif |
5638 | |
5639 | // CFG and pinned nodes already handled |
5640 | if( n->in(0) ) { |
5641 | if( n->in(0)->is_top() ) return; // Dead? |
5642 | |
5643 | // We'd like +VerifyLoopOptimizations to not believe that Mod's/Loads |
5644 | // _must_ be pinned (they have to observe their control edge of course). |
5645 | // Unlike Stores (which modify an unallocable resource, the memory |
5646 | // state), Mods/Loads can float around. So free them up. |
5647 | switch( n->Opcode() ) { |
5648 | case Op_DivI: |
5649 | case Op_DivF: |
5650 | case Op_DivD: |
5651 | case Op_ModI: |
5652 | case Op_ModF: |
5653 | case Op_ModD: |
5654 | case Op_LoadB: // Same with Loads; they can sink |
5655 | case Op_LoadUB: // during loop optimizations. |
5656 | case Op_LoadUS: |
5657 | case Op_LoadD: |
5658 | case Op_LoadF: |
5659 | case Op_LoadI: |
5660 | case Op_LoadKlass: |
5661 | case Op_LoadNKlass: |
5662 | case Op_LoadL: |
5663 | case Op_LoadS: |
5664 | case Op_LoadP: |
5665 | case Op_LoadN: |
5666 | case Op_LoadRange: |
5667 | case Op_LoadD_unaligned: |
5668 | case Op_LoadL_unaligned: |
5669 | case Op_StrComp: // Does a bunch of load-like effects |
5670 | case Op_StrEquals: |
5671 | case Op_StrIndexOf: |
5672 | case Op_StrIndexOfChar: |
5673 | case Op_AryEq: |
5674 | case Op_HasNegatives: |
5675 | pinned = false; |
5676 | } |
5677 | if (n->is_CMove() || n->is_ConstraintCast()) { |
5678 | pinned = false; |
5679 | } |
5680 | if( pinned ) { |
5681 | IdealLoopTree *chosen_loop = get_loop(n->is_CFG() ? n : get_ctrl(n)); |
5682 | if( !chosen_loop->_child ) // Inner loop? |
5683 | chosen_loop->_body.push(n); // Collect inner loops |
5684 | return; |
5685 | } |
5686 | } else { // No slot zero |
5687 | if( n->is_CFG() ) { // CFG with no slot 0 is dead |
5688 | _nodes.map(n->_idx,0); // No block setting, it's globally dead |
5689 | return; |
5690 | } |
5691 | assert(!n->is_CFG() || n->outcnt() == 0, "")do { if (!(!n->is_CFG() || n->outcnt() == 0)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5691, "assert(" "!n->is_CFG() || n->outcnt() == 0" ") failed" , ""); ::breakpoint(); } } while (0); |
5692 | } |
5693 | |
5694 | // Do I have a "safe range" I can select over? |
5695 | Node *early = get_ctrl(n);// Early location already computed |
5696 | |
5697 | // Compute latest point this Node can go |
5698 | Node *LCA = get_late_ctrl( n, early ); |
5699 | // LCA is NULL due to uses being dead |
5700 | if( LCA == NULL__null ) { |
5701 | #ifdef ASSERT1 |
5702 | for (DUIterator i1 = n->outs(); n->has_out(i1); i1++) { |
5703 | assert( _nodes[n->out(i1)->_idx] == NULL, "all uses must also be dead")do { if (!(_nodes[n->out(i1)->_idx] == __null)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5703, "assert(" "_nodes[n->out(i1)->_idx] == __null" ") failed" , "all uses must also be dead"); ::breakpoint(); } } while (0 ); |
5704 | } |
5705 | #endif |
5706 | _nodes.map(n->_idx, 0); // This node is useless |
5707 | _deadlist.push(n); |
5708 | return; |
5709 | } |
5710 | assert(LCA != NULL && !LCA->is_top(), "no dead nodes")do { if (!(LCA != __null && !LCA->is_top())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5710, "assert(" "LCA != __null && !LCA->is_top()" ") failed", "no dead nodes"); ::breakpoint(); } } while (0); |
5711 | |
5712 | Node *legal = LCA; // Walk 'legal' up the IDOM chain |
5713 | Node *least = legal; // Best legal position so far |
5714 | while( early != legal ) { // While not at earliest legal |
5715 | #ifdef ASSERT1 |
5716 | if (legal->is_Start() && !early->is_Root()) { |
5717 | // Bad graph. Print idom path and fail. |
5718 | dump_bad_graph("Bad graph detected in build_loop_late", n, early, LCA); |
5719 | assert(false, "Bad graph detected in build_loop_late")do { if (!(false)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5719, "assert(" "false" ") failed", "Bad graph detected in build_loop_late" ); ::breakpoint(); } } while (0); |
5720 | } |
5721 | #endif |
5722 | // Find least loop nesting depth |
5723 | legal = idom(legal); // Bump up the IDOM tree |
5724 | // Check for lower nesting depth |
5725 | if( get_loop(legal)->_nest < get_loop(least)->_nest ) |
5726 | least = legal; |
5727 | } |
5728 | assert(early == legal || legal != C->root(), "bad dominance of inputs")do { if (!(early == legal || legal != C->root())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5728, "assert(" "early == legal || legal != C->root()" ") failed" , "bad dominance of inputs"); ::breakpoint(); } } while (0); |
5729 | |
5730 | // Try not to place code on a loop entry projection |
5731 | // which can inhibit range check elimination. |
5732 | if (least != early) { |
5733 | Node* ctrl_out = least->unique_ctrl_out(); |
5734 | if (ctrl_out && ctrl_out->is_Loop() && |
5735 | least == ctrl_out->in(LoopNode::EntryControl)) { |
5736 | // Move the node above predicates as far up as possible so a |
5737 | // following pass of loop predication doesn't hoist a predicate |
5738 | // that depends on it above that node. |
5739 | Node* new_ctrl = least; |
5740 | for (;;) { |
5741 | if (!new_ctrl->is_Proj()) { |
5742 | break; |
5743 | } |
5744 | CallStaticJavaNode* call = new_ctrl->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none); |
5745 | if (call == NULL__null) { |
5746 | break; |
5747 | } |
5748 | int req = call->uncommon_trap_request(); |
5749 | Deoptimization::DeoptReason trap_reason = Deoptimization::trap_request_reason(req); |
5750 | if (trap_reason != Deoptimization::Reason_loop_limit_check && |
5751 | trap_reason != Deoptimization::Reason_predicate && |
5752 | trap_reason != Deoptimization::Reason_profile_predicate) { |
5753 | break; |
5754 | } |
5755 | Node* c = new_ctrl->in(0)->in(0); |
5756 | if (is_dominator(c, early) && c != early) { |
5757 | break; |
5758 | } |
5759 | new_ctrl = c; |
5760 | } |
5761 | least = new_ctrl; |
5762 | } |
5763 | } |
5764 | |
5765 | #ifdef ASSERT1 |
5766 | // If verifying, verify that 'verify_me' has a legal location |
5767 | // and choose it as our location. |
5768 | if( _verify_me ) { |
5769 | Node *v_ctrl = _verify_me->get_ctrl_no_update(n); |
5770 | Node *legal = LCA; |
5771 | while( early != legal ) { // While not at earliest legal |
5772 | if( legal == v_ctrl ) break; // Check for prior good location |
5773 | legal = idom(legal) ;// Bump up the IDOM tree |
5774 | } |
5775 | // Check for prior good location |
5776 | if( legal == v_ctrl ) least = legal; // Keep prior if found |
5777 | } |
5778 | #endif |
5779 | |
5780 | // Assign discovered "here or above" point |
5781 | least = find_non_split_ctrl(least); |
5782 | verify_strip_mined_scheduling(n, least); |
5783 | set_ctrl(n, least); |
5784 | |
5785 | // Collect inner loop bodies |
5786 | IdealLoopTree *chosen_loop = get_loop(least); |
5787 | if( !chosen_loop->_child ) // Inner loop? |
5788 | chosen_loop->_body.push(n);// Collect inner loops |
5789 | } |
5790 | |
5791 | #ifdef ASSERT1 |
5792 | void PhaseIdealLoop::dump_bad_graph(const char* msg, Node* n, Node* early, Node* LCA) { |
5793 | tty->print_cr("%s", msg); |
5794 | tty->print("n: "); n->dump(); |
5795 | tty->print("early(n): "); early->dump(); |
5796 | if (n->in(0) != NULL__null && !n->in(0)->is_top() && |
5797 | n->in(0) != early && !n->in(0)->is_Root()) { |
5798 | tty->print("n->in(0): "); n->in(0)->dump(); |
5799 | } |
5800 | for (uint i = 1; i < n->req(); i++) { |
5801 | Node* in1 = n->in(i); |
5802 | if (in1 != NULL__null && in1 != n && !in1->is_top()) { |
5803 | tty->print("n->in(%d): ", i); in1->dump(); |
5804 | Node* in1_early = get_ctrl(in1); |
5805 | tty->print("early(n->in(%d)): ", i); in1_early->dump(); |
5806 | if (in1->in(0) != NULL__null && !in1->in(0)->is_top() && |
5807 | in1->in(0) != in1_early && !in1->in(0)->is_Root()) { |
5808 | tty->print("n->in(%d)->in(0): ", i); in1->in(0)->dump(); |
5809 | } |
5810 | for (uint j = 1; j < in1->req(); j++) { |
5811 | Node* in2 = in1->in(j); |
5812 | if (in2 != NULL__null && in2 != n && in2 != in1 && !in2->is_top()) { |
5813 | tty->print("n->in(%d)->in(%d): ", i, j); in2->dump(); |
5814 | Node* in2_early = get_ctrl(in2); |
5815 | tty->print("early(n->in(%d)->in(%d)): ", i, j); in2_early->dump(); |
5816 | if (in2->in(0) != NULL__null && !in2->in(0)->is_top() && |
5817 | in2->in(0) != in2_early && !in2->in(0)->is_Root()) { |
5818 | tty->print("n->in(%d)->in(%d)->in(0): ", i, j); in2->in(0)->dump(); |
5819 | } |
5820 | } |
5821 | } |
5822 | } |
5823 | } |
5824 | tty->cr(); |
5825 | tty->print("LCA(n): "); LCA->dump(); |
5826 | for (uint i = 0; i < n->outcnt(); i++) { |
5827 | Node* u1 = n->raw_out(i); |
5828 | if (u1 == n) |
5829 | continue; |
5830 | tty->print("n->out(%d): ", i); u1->dump(); |
5831 | if (u1->is_CFG()) { |
5832 | for (uint j = 0; j < u1->outcnt(); j++) { |
5833 | Node* u2 = u1->raw_out(j); |
5834 | if (u2 != u1 && u2 != n && u2->is_CFG()) { |
5835 | tty->print("n->out(%d)->out(%d): ", i, j); u2->dump(); |
5836 | } |
5837 | } |
5838 | } else { |
5839 | Node* u1_later = get_ctrl(u1); |
5840 | tty->print("later(n->out(%d)): ", i); u1_later->dump(); |
5841 | if (u1->in(0) != NULL__null && !u1->in(0)->is_top() && |
5842 | u1->in(0) != u1_later && !u1->in(0)->is_Root()) { |
5843 | tty->print("n->out(%d)->in(0): ", i); u1->in(0)->dump(); |
5844 | } |
5845 | for (uint j = 0; j < u1->outcnt(); j++) { |
5846 | Node* u2 = u1->raw_out(j); |
5847 | if (u2 == n || u2 == u1) |
5848 | continue; |
5849 | tty->print("n->out(%d)->out(%d): ", i, j); u2->dump(); |
5850 | if (!u2->is_CFG()) { |
5851 | Node* u2_later = get_ctrl(u2); |
5852 | tty->print("later(n->out(%d)->out(%d)): ", i, j); u2_later->dump(); |
5853 | if (u2->in(0) != NULL__null && !u2->in(0)->is_top() && |
5854 | u2->in(0) != u2_later && !u2->in(0)->is_Root()) { |
5855 | tty->print("n->out(%d)->in(0): ", i); u2->in(0)->dump(); |
5856 | } |
5857 | } |
5858 | } |
5859 | } |
5860 | } |
5861 | tty->cr(); |
5862 | tty->print_cr("idoms of early %d:", early->_idx); |
5863 | dump_idom(early); |
5864 | tty->cr(); |
5865 | tty->print_cr("idoms of (wrong) LCA %d:", LCA->_idx); |
5866 | dump_idom(LCA); |
5867 | tty->cr(); |
5868 | dump_real_LCA(early, LCA); |
5869 | tty->cr(); |
5870 | } |
5871 | |
5872 | // Find the real LCA of early and the wrongly assumed LCA. |
5873 | void PhaseIdealLoop::dump_real_LCA(Node* early, Node* wrong_lca) { |
5874 | assert(!is_dominator(early, wrong_lca) && !is_dominator(early, wrong_lca),do { if (!(!is_dominator(early, wrong_lca) && !is_dominator (early, wrong_lca))) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5875, "assert(" "!is_dominator(early, wrong_lca) && !is_dominator(early, wrong_lca)" ") failed", "sanity check that one node does not dominate the other" ); ::breakpoint(); } } while (0) |
5875 | "sanity check that one node does not dominate the other")do { if (!(!is_dominator(early, wrong_lca) && !is_dominator (early, wrong_lca))) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5875, "assert(" "!is_dominator(early, wrong_lca) && !is_dominator(early, wrong_lca)" ") failed", "sanity check that one node does not dominate the other" ); ::breakpoint(); } } while (0); |
5876 | assert(!has_ctrl(early) && !has_ctrl(wrong_lca), "sanity check, no data nodes")do { if (!(!has_ctrl(early) && !has_ctrl(wrong_lca))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5876, "assert(" "!has_ctrl(early) && !has_ctrl(wrong_lca)" ") failed", "sanity check, no data nodes"); ::breakpoint(); } } while (0); |
5877 | |
5878 | ResourceMark rm; |
5879 | Node_List nodes_seen; |
5880 | Node* real_LCA = NULL__null; |
5881 | Node* n1 = wrong_lca; |
5882 | Node* n2 = early; |
5883 | uint count_1 = 0; |
5884 | uint count_2 = 0; |
5885 | // Add early and wrong_lca to simplify calculation of idom indices |
5886 | nodes_seen.push(n1); |
5887 | nodes_seen.push(n2); |
5888 | |
5889 | // Walk the idom chain up from early and wrong_lca and stop when they intersect. |
5890 | while (!n1->is_Start() && !n2->is_Start()) { |
5891 | n1 = idom(n1); |
5892 | n2 = idom(n2); |
5893 | if (n1 == n2) { |
5894 | // Both idom chains intersect at the same index |
5895 | real_LCA = n1; |
5896 | count_1 = nodes_seen.size() / 2; |
5897 | count_2 = count_1; |
5898 | break; |
5899 | } |
5900 | if (check_idom_chains_intersection(n1, count_1, count_2, &nodes_seen)) { |
5901 | real_LCA = n1; |
5902 | break; |
5903 | } |
5904 | if (check_idom_chains_intersection(n2, count_2, count_1, &nodes_seen)) { |
5905 | real_LCA = n2; |
5906 | break; |
5907 | } |
5908 | nodes_seen.push(n1); |
5909 | nodes_seen.push(n2); |
5910 | } |
5911 | |
5912 | assert(real_LCA != NULL, "must always find an LCA")do { if (!(real_LCA != __null)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 5912, "assert(" "real_LCA != __null" ") failed", "must always find an LCA" ); ::breakpoint(); } } while (0); |
5913 | tty->print_cr("Real LCA of early %d (idom[%d]) and (wrong) LCA %d (idom[%d]):", early->_idx, count_2, wrong_lca->_idx, count_1); |
5914 | real_LCA->dump(); |
5915 | } |
5916 | |
5917 | // Check if n is already on nodes_seen (i.e. idom chains of early and wrong_lca intersect at n). Determine the idom index of n |
5918 | // on both idom chains and return them in idom_idx_new and idom_idx_other, respectively. |
5919 | bool PhaseIdealLoop::check_idom_chains_intersection(const Node* n, uint& idom_idx_new, uint& idom_idx_other, const Node_List* nodes_seen) const { |
5920 | if (nodes_seen->contains(n)) { |
5921 | // The idom chain has just discovered n. |
5922 | // Divide by 2 because nodes_seen contains the same amount of nodes from both chains. |
5923 | idom_idx_new = nodes_seen->size() / 2; |
5924 | |
5925 | // The other chain already contained n. Search the index. |
5926 | for (uint i = 0; i < nodes_seen->size(); i++) { |
5927 | if (nodes_seen->at(i) == n) { |
5928 | // Divide by 2 because nodes_seen contains the same amount of nodes from both chains. |
5929 | idom_idx_other = i / 2; |
5930 | } |
5931 | } |
5932 | return true; |
5933 | } |
5934 | return false; |
5935 | } |
5936 | #endif // ASSERT |
5937 | |
5938 | #ifndef PRODUCT |
5939 | //------------------------------dump------------------------------------------- |
5940 | void PhaseIdealLoop::dump() const { |
5941 | ResourceMark rm; |
5942 | Node_Stack stack(C->live_nodes() >> 2); |
5943 | Node_List rpo_list; |
5944 | VectorSet visited; |
5945 | visited.set(C->top()->_idx); |
5946 | rpo(C->root(), stack, visited, rpo_list); |
5947 | // Dump root loop indexed by last element in PO order |
5948 | dump(_ltree_root, rpo_list.size(), rpo_list); |
5949 | } |
5950 | |
5951 | void PhaseIdealLoop::dump(IdealLoopTree* loop, uint idx, Node_List &rpo_list) const { |
5952 | loop->dump_head(); |
5953 | |
5954 | // Now scan for CFG nodes in the same loop |
5955 | for (uint j = idx; j > 0; j--) { |
5956 | Node* n = rpo_list[j-1]; |
5957 | if (!_nodes[n->_idx]) // Skip dead nodes |
5958 | continue; |
5959 | |
5960 | if (get_loop(n) != loop) { // Wrong loop nest |
5961 | if (get_loop(n)->_head == n && // Found nested loop? |
5962 | get_loop(n)->_parent == loop) |
5963 | dump(get_loop(n), rpo_list.size(), rpo_list); // Print it nested-ly |
5964 | continue; |
5965 | } |
5966 | |
5967 | // Dump controlling node |
5968 | tty->sp(2 * loop->_nest); |
5969 | tty->print("C"); |
5970 | if (n == C->root()) { |
5971 | n->dump(); |
5972 | } else { |
5973 | Node* cached_idom = idom_no_update(n); |
5974 | Node* computed_idom = n->in(0); |
5975 | if (n->is_Region()) { |
5976 | computed_idom = compute_idom(n); |
5977 | // computed_idom() will return n->in(0) when idom(n) is an IfNode (or |
5978 | // any MultiBranch ctrl node), so apply a similar transform to |
5979 | // the cached idom returned from idom_no_update. |
5980 | cached_idom = find_non_split_ctrl(cached_idom); |
5981 | } |
5982 | tty->print(" ID:%d", computed_idom->_idx); |
5983 | n->dump(); |
5984 | if (cached_idom != computed_idom) { |
5985 | tty->print_cr("*** BROKEN IDOM! Computed as: %d, cached as: %d", |
5986 | computed_idom->_idx, cached_idom->_idx); |
5987 | } |
5988 | } |
5989 | // Dump nodes it controls |
5990 | for (uint k = 0; k < _nodes.Size(); k++) { |
5991 | // (k < C->unique() && get_ctrl(find(k)) == n) |
5992 | if (k < C->unique() && _nodes[k] == (Node*)((intptr_t)n + 1)) { |
5993 | Node* m = C->root()->find(k); |
5994 | if (m && m->outcnt() > 0) { |
5995 | if (!(has_ctrl(m) && get_ctrl_no_update(m) == n)) { |
5996 | tty->print_cr("*** BROKEN CTRL ACCESSOR! _nodes[k] is %p, ctrl is %p", |
5997 | _nodes[k], has_ctrl(m) ? get_ctrl_no_update(m) : NULL__null); |
5998 | } |
5999 | tty->sp(2 * loop->_nest + 1); |
6000 | m->dump(); |
6001 | } |
6002 | } |
6003 | } |
6004 | } |
6005 | } |
6006 | |
6007 | void PhaseIdealLoop::dump_idom(Node* n) const { |
6008 | if (has_ctrl(n)) { |
6009 | tty->print_cr("No idom for data nodes"); |
6010 | } else { |
6011 | for (int i = 0; i < 100 && !n->is_Start(); i++) { |
6012 | tty->print("idom[%d] ", i); |
6013 | n->dump(); |
6014 | n = idom(n); |
6015 | } |
6016 | } |
6017 | } |
6018 | #endif // NOT PRODUCT |
6019 | |
6020 | // Collect a R-P-O for the whole CFG. |
6021 | // Result list is in post-order (scan backwards for RPO) |
6022 | void PhaseIdealLoop::rpo(Node* start, Node_Stack &stk, VectorSet &visited, Node_List &rpo_list) const { |
6023 | stk.push(start, 0); |
6024 | visited.set(start->_idx); |
6025 | |
6026 | while (stk.is_nonempty()) { |
6027 | Node* m = stk.node(); |
6028 | uint idx = stk.index(); |
6029 | if (idx < m->outcnt()) { |
6030 | stk.set_index(idx + 1); |
6031 | Node* n = m->raw_out(idx); |
6032 | if (n->is_CFG() && !visited.test_set(n->_idx)) { |
6033 | stk.push(n, 0); |
6034 | } |
6035 | } else { |
6036 | rpo_list.push(m); |
6037 | stk.pop(); |
6038 | } |
6039 | } |
6040 | } |
6041 | |
6042 | |
6043 | //============================================================================= |
6044 | //------------------------------LoopTreeIterator------------------------------- |
6045 | |
6046 | // Advance to next loop tree using a preorder, left-to-right traversal. |
6047 | void LoopTreeIterator::next() { |
6048 | assert(!done(), "must not be done.")do { if (!(!done())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 6048, "assert(" "!done()" ") failed", "must not be done."); ::breakpoint(); } } while (0); |
6049 | if (_curnt->_child != NULL__null) { |
6050 | _curnt = _curnt->_child; |
6051 | } else if (_curnt->_next != NULL__null) { |
6052 | _curnt = _curnt->_next; |
6053 | } else { |
6054 | while (_curnt != _root && _curnt->_next == NULL__null) { |
6055 | _curnt = _curnt->_parent; |
6056 | } |
6057 | if (_curnt == _root) { |
6058 | _curnt = NULL__null; |
6059 | assert(done(), "must be done.")do { if (!(done())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 6059, "assert(" "done()" ") failed", "must be done."); ::breakpoint (); } } while (0); |
6060 | } else { |
6061 | assert(_curnt->_next != NULL, "must be more to do")do { if (!(_curnt->_next != __null)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopnode.cpp" , 6061, "assert(" "_curnt->_next != __null" ") failed", "must be more to do" ); ::breakpoint(); } } while (0); |
6062 | _curnt = _curnt->_next; |
6063 | } |
6064 | } |
6065 | } |