| File: | jdk/src/hotspot/share/opto/loopPredicate.cpp |
| Warning: | line 334, column 13 Value stored to 'uncommon_proj' during its initialization is never read |
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| 1 | /* |
| 2 | * Copyright (c) 2011, 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 "opto/loopnode.hpp" |
| 27 | #include "opto/addnode.hpp" |
| 28 | #include "opto/callnode.hpp" |
| 29 | #include "opto/connode.hpp" |
| 30 | #include "opto/convertnode.hpp" |
| 31 | #include "opto/loopnode.hpp" |
| 32 | #include "opto/matcher.hpp" |
| 33 | #include "opto/mulnode.hpp" |
| 34 | #include "opto/opaquenode.hpp" |
| 35 | #include "opto/rootnode.hpp" |
| 36 | #include "opto/subnode.hpp" |
| 37 | #include <fenv.h> |
| 38 | #include <math.h> |
| 39 | |
| 40 | /* |
| 41 | * The general idea of Loop Predication is to insert a predicate on the entry |
| 42 | * path to a loop, and raise a uncommon trap if the check of the condition fails. |
| 43 | * The condition checks are promoted from inside the loop body, and thus |
| 44 | * the checks inside the loop could be eliminated. Currently, loop predication |
| 45 | * optimization has been applied to remove array range check and loop invariant |
| 46 | * checks (such as null checks). |
| 47 | * |
| 48 | * There are at least 3 kinds of predicates: a place holder inserted |
| 49 | * at parse time, the tests added by predication above the place |
| 50 | * holder (referred to as concrete predicates), skeleton predicates |
| 51 | * that are added between main loop and pre loop to protect C2 from |
| 52 | * inconsistencies in some rare cases of over unrolling. Skeleton |
| 53 | * predicates themselves are expanded and updated as unrolling |
| 54 | * proceeds. They don't compile to any code. |
| 55 | * |
| 56 | */ |
| 57 | |
| 58 | //-------------------------------register_control------------------------- |
| 59 | void PhaseIdealLoop::register_control(Node* n, IdealLoopTree *loop, Node* pred, bool update_body) { |
| 60 | assert(n->is_CFG(), "msust be control node")do { if (!(n->is_CFG())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 60, "assert(" "n->is_CFG()" ") failed", "msust be control node" ); ::breakpoint(); } } while (0); |
| 61 | _igvn.register_new_node_with_optimizer(n); |
| 62 | if (update_body) { |
| 63 | loop->_body.push(n); |
| 64 | } |
| 65 | set_loop(n, loop); |
| 66 | // When called from beautify_loops() idom is not constructed yet. |
| 67 | if (_idom != NULL__null) { |
| 68 | set_idom(n, pred, dom_depth(pred)); |
| 69 | } |
| 70 | } |
| 71 | |
| 72 | //------------------------------create_new_if_for_predicate------------------------ |
| 73 | // create a new if above the uct_if_pattern for the predicate to be promoted. |
| 74 | // |
| 75 | // before after |
| 76 | // ---------- ---------- |
| 77 | // ctrl ctrl |
| 78 | // | | |
| 79 | // | | |
| 80 | // v v |
| 81 | // iff new_iff |
| 82 | // / \ / \ |
| 83 | // / \ / \ |
| 84 | // v v v v |
| 85 | // uncommon_proj cont_proj if_uct if_cont |
| 86 | // \ | | | | |
| 87 | // \ | | | | |
| 88 | // v v v | v |
| 89 | // rgn loop | iff |
| 90 | // | | / \ |
| 91 | // | | / \ |
| 92 | // v | v v |
| 93 | // uncommon_trap | uncommon_proj cont_proj |
| 94 | // \ \ | | |
| 95 | // \ \ | | |
| 96 | // v v v v |
| 97 | // rgn loop |
| 98 | // | |
| 99 | // | |
| 100 | // v |
| 101 | // uncommon_trap |
| 102 | // |
| 103 | // |
| 104 | // We will create a region to guard the uct call if there is no one there. |
| 105 | // The continuation projection (if_cont) of the new_iff is returned which |
| 106 | // is by default a true projection if 'if_cont_is_true_proj' is true. |
| 107 | // Otherwise, the continuation projection is set up to be the false |
| 108 | // projection. This code is also used to clone predicates to cloned loops. |
| 109 | ProjNode* PhaseIdealLoop::create_new_if_for_predicate(ProjNode* cont_proj, Node* new_entry, |
| 110 | Deoptimization::DeoptReason reason, int opcode, |
| 111 | bool if_cont_is_true_proj, Node_List* old_new, |
| 112 | UnswitchingAction unswitching_action) { |
| 113 | assert(cont_proj->is_uncommon_trap_if_pattern(reason), "must be a uct if pattern!")do { if (!(cont_proj->is_uncommon_trap_if_pattern(reason)) ) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 113, "assert(" "cont_proj->is_uncommon_trap_if_pattern(reason)" ") failed", "must be a uct if pattern!"); ::breakpoint(); } } while (0); |
| 114 | IfNode* iff = cont_proj->in(0)->as_If(); |
| 115 | |
| 116 | ProjNode *uncommon_proj = iff->proj_out(1 - cont_proj->_con); |
| 117 | Node *rgn = uncommon_proj->unique_ctrl_out(); |
| 118 | assert(rgn->is_Region() || rgn->is_Call(), "must be a region or call uct")do { if (!(rgn->is_Region() || rgn->is_Call())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 118, "assert(" "rgn->is_Region() || rgn->is_Call()" ") failed" , "must be a region or call uct"); ::breakpoint(); } } while ( 0); |
| 119 | |
| 120 | uint proj_index = 1; // region's edge corresponding to uncommon_proj |
| 121 | if (!rgn->is_Region()) { // create a region to guard the call |
| 122 | assert(rgn->is_Call(), "must be call uct")do { if (!(rgn->is_Call())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 122, "assert(" "rgn->is_Call()" ") failed", "must be call uct" ); ::breakpoint(); } } while (0); |
| 123 | CallNode* call = rgn->as_Call(); |
| 124 | IdealLoopTree* loop = get_loop(call); |
| 125 | rgn = new RegionNode(1); |
| 126 | Node* uncommon_proj_orig = uncommon_proj; |
| 127 | uncommon_proj = uncommon_proj->clone()->as_Proj(); |
| 128 | register_control(uncommon_proj, loop, iff); |
| 129 | rgn->add_req(uncommon_proj); |
| 130 | register_control(rgn, loop, uncommon_proj); |
| 131 | _igvn.replace_input_of(call, 0, rgn); |
| 132 | // When called from beautify_loops() idom is not constructed yet. |
| 133 | if (_idom != NULL__null) { |
| 134 | set_idom(call, rgn, dom_depth(rgn)); |
| 135 | } |
| 136 | // Move nodes pinned on the projection or whose control is set to |
| 137 | // the projection to the region. |
| 138 | lazy_replace(uncommon_proj_orig, rgn); |
| 139 | } else { |
| 140 | // Find region's edge corresponding to uncommon_proj |
| 141 | for (; proj_index < rgn->req(); proj_index++) |
| 142 | if (rgn->in(proj_index) == uncommon_proj) break; |
| 143 | assert(proj_index < rgn->req(), "sanity")do { if (!(proj_index < rgn->req())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 143, "assert(" "proj_index < rgn->req()" ") failed", "sanity" ); ::breakpoint(); } } while (0); |
| 144 | } |
| 145 | |
| 146 | Node* entry = iff->in(0); |
| 147 | if (new_entry != NULL__null) { |
| 148 | // Clonning the predicate to new location. |
| 149 | entry = new_entry; |
| 150 | } |
| 151 | // Create new_iff |
| 152 | IdealLoopTree* lp = get_loop(entry); |
| 153 | IfNode* new_iff = NULL__null; |
| 154 | if (opcode == Op_If) { |
| 155 | new_iff = new IfNode(entry, iff->in(1), iff->_prob, iff->_fcnt); |
| 156 | } else { |
| 157 | assert(opcode == Op_RangeCheck, "no other if variant here")do { if (!(opcode == Op_RangeCheck)) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 157, "assert(" "opcode == Op_RangeCheck" ") failed", "no other if variant here" ); ::breakpoint(); } } while (0); |
| 158 | new_iff = new RangeCheckNode(entry, iff->in(1), iff->_prob, iff->_fcnt); |
| 159 | } |
| 160 | register_control(new_iff, lp, entry); |
| 161 | Node* if_cont; |
| 162 | Node* if_uct; |
| 163 | if (if_cont_is_true_proj) { |
| 164 | if_cont = new IfTrueNode(new_iff); |
| 165 | if_uct = new IfFalseNode(new_iff); |
| 166 | } else { |
| 167 | if_uct = new IfTrueNode(new_iff); |
| 168 | if_cont = new IfFalseNode(new_iff); |
| 169 | } |
| 170 | |
| 171 | if (cont_proj->is_IfFalse()) { |
| 172 | // Swap |
| 173 | Node* tmp = if_uct; if_uct = if_cont; if_cont = tmp; |
| 174 | } |
| 175 | register_control(if_cont, lp, new_iff); |
| 176 | register_control(if_uct, get_loop(rgn), new_iff); |
| 177 | |
| 178 | // if_uct to rgn |
| 179 | _igvn.hash_delete(rgn); |
| 180 | rgn->add_req(if_uct); |
| 181 | // When called from beautify_loops() idom is not constructed yet. |
| 182 | if (_idom != NULL__null) { |
| 183 | Node* ridom = idom(rgn); |
| 184 | Node* nrdom = dom_lca_internal(ridom, new_iff); |
| 185 | set_idom(rgn, nrdom, dom_depth(rgn)); |
| 186 | } |
| 187 | |
| 188 | // If rgn has phis add new edges which has the same |
| 189 | // value as on original uncommon_proj pass. |
| 190 | assert(rgn->in(rgn->req() -1) == if_uct, "new edge should be last")do { if (!(rgn->in(rgn->req() -1) == if_uct)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 190, "assert(" "rgn->in(rgn->req() -1) == if_uct" ") failed" , "new edge should be last"); ::breakpoint(); } } while (0); |
| 191 | bool has_phi = false; |
| 192 | for (DUIterator_Fast imax, i = rgn->fast_outs(imax); i < imax; i++) { |
| 193 | Node* use = rgn->fast_out(i); |
| 194 | if (use->is_Phi() && use->outcnt() > 0) { |
| 195 | assert(use->in(0) == rgn, "")do { if (!(use->in(0) == rgn)) { (*g_assert_poison) = 'X'; ; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 195, "assert(" "use->in(0) == rgn" ") failed", ""); ::breakpoint (); } } while (0); |
| 196 | _igvn.rehash_node_delayed(use); |
| 197 | Node* phi_input = use->in(proj_index); |
| 198 | if (unswitching_action == UnswitchingAction::FastLoopCloning |
| 199 | && !phi_input->is_CFG() && !phi_input->is_Phi() && get_ctrl(phi_input) == uncommon_proj) { |
| 200 | // There are some control dependent nodes on the uncommon projection and we are currently copying predicates |
| 201 | // to the fast loop in loop unswitching (first step, slow loop is processed afterwards). For the fast loop, |
| 202 | // we need to clone all the data nodes in the chain from the phi ('use') up until the node whose control input |
| 203 | // is the uncommon_proj. The slow loop can reuse the old data nodes and thus only needs to update the control |
| 204 | // input to the uncommon_proj (done on the next invocation of this method when 'unswitch_is_slow_loop' is true. |
| 205 | assert(LoopUnswitching, "sanity check")do { if (!(LoopUnswitching)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 205, "assert(" "LoopUnswitching" ") failed", "sanity check" ); ::breakpoint(); } } while (0); |
| 206 | phi_input = clone_data_nodes_for_fast_loop(phi_input, uncommon_proj, if_uct, old_new); |
| 207 | } else if (unswitching_action == UnswitchingAction::SlowLoopRewiring) { |
| 208 | // Replace phi input for the old predicate path with TOP as the predicate is dying anyways. This avoids the need |
| 209 | // to clone the data nodes again for the slow loop. |
| 210 | assert(LoopUnswitching, "sanity check")do { if (!(LoopUnswitching)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 210, "assert(" "LoopUnswitching" ") failed", "sanity check" ); ::breakpoint(); } } while (0); |
| 211 | _igvn.replace_input_of(use, proj_index, C->top()); |
| 212 | } |
| 213 | use->add_req(phi_input); |
| 214 | has_phi = true; |
| 215 | } |
| 216 | } |
| 217 | assert(!has_phi || rgn->req() > 3, "no phis when region is created")do { if (!(!has_phi || rgn->req() > 3)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 217, "assert(" "!has_phi || rgn->req() > 3" ") failed" , "no phis when region is created"); ::breakpoint(); } } while (0); |
| 218 | if (unswitching_action == UnswitchingAction::SlowLoopRewiring) { |
| 219 | // Rewire the control dependent data nodes for the slow loop from the old to the new uncommon projection. |
| 220 | assert(uncommon_proj->outcnt() > 1 && old_new == NULL, "sanity")do { if (!(uncommon_proj->outcnt() > 1 && old_new == __null)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 220, "assert(" "uncommon_proj->outcnt() > 1 && old_new == __null" ") failed", "sanity"); ::breakpoint(); } } while (0); |
| 221 | for (DUIterator_Fast jmax, j = uncommon_proj->fast_outs(jmax); j < jmax; j++) { |
| 222 | Node* data = uncommon_proj->fast_out(j); |
| 223 | if (!data->is_CFG()) { |
| 224 | _igvn.replace_input_of(data, 0, if_uct); |
| 225 | set_ctrl(data, if_uct); |
| 226 | --j; |
| 227 | --jmax; |
| 228 | } |
| 229 | } |
| 230 | } |
| 231 | |
| 232 | if (new_entry == NULL__null) { |
| 233 | // Attach if_cont to iff |
| 234 | _igvn.replace_input_of(iff, 0, if_cont); |
| 235 | if (_idom != NULL__null) { |
| 236 | set_idom(iff, if_cont, dom_depth(iff)); |
| 237 | } |
| 238 | } |
| 239 | return if_cont->as_Proj(); |
| 240 | } |
| 241 | |
| 242 | // Clone data nodes for the fast loop while creating a new If with create_new_if_for_predicate. Returns the node which is |
| 243 | // used for the uncommon trap phi input. |
| 244 | Node* PhaseIdealLoop::clone_data_nodes_for_fast_loop(Node* phi_input, ProjNode* uncommon_proj, Node* if_uct, Node_List* old_new) { |
| 245 | // Step 1: Clone all nodes on the data chain but do not rewire anything, yet. Keep track of the cloned nodes |
| 246 | // by using the old_new mapping. This mapping is then used in step 2 to rewire the cloned nodes accordingly. |
| 247 | DEBUG_ONLY(uint last_idx = C->unique();)uint last_idx = C->unique(); |
| 248 | Unique_Node_List list; |
| 249 | list.push(phi_input); |
| 250 | for (uint j = 0; j < list.size(); j++) { |
| 251 | Node* next = list.at(j); |
| 252 | Node* clone = next->clone(); |
| 253 | _igvn.register_new_node_with_optimizer(clone); |
| 254 | old_new->map(next->_idx, clone); |
| 255 | for (uint k = 1; k < next->req(); k++) { |
| 256 | Node* in = next->in(k); |
| 257 | if (!in->is_Phi() && get_ctrl(in) == uncommon_proj) { |
| 258 | list.push(in); |
| 259 | } |
| 260 | } |
| 261 | } |
| 262 | |
| 263 | // Step 2: All nodes are cloned. Rewire them by using the old_new mapping. |
| 264 | for (uint j = 0; j < list.size(); j++) { |
| 265 | Node* next = list.at(j); |
| 266 | Node* clone = old_new->at(next->_idx); |
| 267 | assert(clone != NULL && clone->_idx >= last_idx, "must exist and be a proper clone")do { if (!(clone != __null && clone->_idx >= last_idx )) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 267, "assert(" "clone != __null && clone->_idx >= last_idx" ") failed", "must exist and be a proper clone"); ::breakpoint (); } } while (0); |
| 268 | if (next->in(0) == uncommon_proj) { |
| 269 | // All data nodes with a control input to the uncommon projection in the chain need to be rewired to the new uncommon |
| 270 | // projection (could not only be the last data node in the chain but also, for example, a DivNode within the chain). |
| 271 | _igvn.replace_input_of(clone, 0, if_uct); |
| 272 | set_ctrl(clone, if_uct); |
| 273 | } |
| 274 | |
| 275 | // Rewire the inputs of the cloned nodes to the old nodes to the new clones. |
| 276 | for (uint k = 1; k < next->req(); k++) { |
| 277 | Node* in = next->in(k); |
| 278 | if (!in->is_Phi()) { |
| 279 | assert(!in->is_CFG(), "must be data node")do { if (!(!in->is_CFG())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 279, "assert(" "!in->is_CFG()" ") failed", "must be data node" ); ::breakpoint(); } } while (0); |
| 280 | Node* in_clone = old_new->at(in->_idx); |
| 281 | if (in_clone != NULL__null) { |
| 282 | assert(in_clone->_idx >= last_idx, "must be a valid clone")do { if (!(in_clone->_idx >= last_idx)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 282, "assert(" "in_clone->_idx >= last_idx" ") failed" , "must be a valid clone"); ::breakpoint(); } } while (0); |
| 283 | _igvn.replace_input_of(clone, k, in_clone); |
| 284 | set_ctrl(clone, if_uct); |
| 285 | } |
| 286 | } |
| 287 | } |
| 288 | } |
| 289 | Node* clone_phi_input = old_new->at(phi_input->_idx); |
| 290 | assert(clone_phi_input != NULL && clone_phi_input->_idx >= last_idx, "must exist and be a proper clone")do { if (!(clone_phi_input != __null && clone_phi_input ->_idx >= last_idx)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 290, "assert(" "clone_phi_input != __null && clone_phi_input->_idx >= last_idx" ") failed", "must exist and be a proper clone"); ::breakpoint (); } } while (0); |
| 291 | return clone_phi_input; |
| 292 | } |
| 293 | //--------------------------clone_predicate----------------------- |
| 294 | ProjNode* PhaseIdealLoop::clone_predicate_to_unswitched_loop(ProjNode* predicate_proj, Node* new_entry, |
| 295 | Deoptimization::DeoptReason reason, Node_List* old_new) { |
| 296 | UnswitchingAction unswitching_action; |
| 297 | if (predicate_proj->other_if_proj()->outcnt() > 1) { |
| 298 | // There are some data dependencies that need to be taken care of when cloning a predicate. |
| 299 | unswitching_action = old_new == NULL__null ? UnswitchingAction::SlowLoopRewiring : UnswitchingAction::FastLoopCloning; |
| 300 | } else { |
| 301 | unswitching_action = UnswitchingAction::None; |
| 302 | } |
| 303 | |
| 304 | ProjNode* new_predicate_proj = create_new_if_for_predicate(predicate_proj, new_entry, reason, Op_If, |
| 305 | true, old_new, unswitching_action); |
| 306 | IfNode* iff = new_predicate_proj->in(0)->as_If(); |
| 307 | Node* ctrl = iff->in(0); |
| 308 | |
| 309 | // Match original condition since predicate's projections could be swapped. |
| 310 | assert(predicate_proj->in(0)->in(1)->in(1)->Opcode()==Op_Opaque1, "must be")do { if (!(predicate_proj->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/loopPredicate.cpp" , 310, "assert(" "predicate_proj->in(0)->in(1)->in(1)->Opcode()==Op_Opaque1" ") failed", "must be"); ::breakpoint(); } } while (0); |
| 311 | Node* opq = new Opaque1Node(C, predicate_proj->in(0)->in(1)->in(1)->in(1)); |
| 312 | C->add_predicate_opaq(opq); |
| 313 | Node* bol = new Conv2BNode(opq); |
| 314 | register_new_node(opq, ctrl); |
| 315 | register_new_node(bol, ctrl); |
| 316 | _igvn.hash_delete(iff); |
| 317 | iff->set_req(1, bol); |
| 318 | return new_predicate_proj; |
| 319 | } |
| 320 | |
| 321 | // Clones skeleton predicates starting at 'old_predicate_proj' by following its control inputs and rewires the control edges of in the loop from |
| 322 | // the old predicates to the new cloned predicates. |
| 323 | void PhaseIdealLoop::clone_skeleton_predicates_to_unswitched_loop(IdealLoopTree* loop, const Node_List& old_new, Deoptimization::DeoptReason reason, |
| 324 | ProjNode* old_predicate_proj, ProjNode* iffast_pred, ProjNode* ifslow_pred) { |
| 325 | assert(iffast_pred->in(0)->is_If() && ifslow_pred->in(0)->is_If(), "sanity check")do { if (!(iffast_pred->in(0)->is_If() && ifslow_pred ->in(0)->is_If())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 325, "assert(" "iffast_pred->in(0)->is_If() && ifslow_pred->in(0)->is_If()" ") failed", "sanity check"); ::breakpoint(); } } while (0); |
| 326 | // Only need to clone range check predicates as those can be changed and duplicated by inserting pre/main/post loops |
| 327 | // and doing loop unrolling. Push the original predicates on a list to later process them in reverse order to keep the |
| 328 | // original predicate order. |
| 329 | Unique_Node_List list; |
| 330 | get_skeleton_predicates(old_predicate_proj, list); |
| 331 | |
| 332 | Node_List to_process; |
| 333 | IfNode* iff = old_predicate_proj->in(0)->as_If(); |
| 334 | ProjNode* uncommon_proj = iff->proj_out(1 - old_predicate_proj->as_Proj()->_con); |
Value stored to 'uncommon_proj' during its initialization is never read | |
| 335 | // Process in reverse order such that 'create_new_if_for_predicate' can be used in 'clone_skeleton_predicate_for_unswitched_loops' |
| 336 | // and the original order is maintained. |
| 337 | for (int i = list.size() - 1; i >= 0; i--) { |
| 338 | Node* predicate = list.at(i); |
| 339 | assert(predicate->in(0)->is_If(), "must be If node")do { if (!(predicate->in(0)->is_If())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 339, "assert(" "predicate->in(0)->is_If()" ") failed" , "must be If node"); ::breakpoint(); } } while (0); |
| 340 | iff = predicate->in(0)->as_If(); |
| 341 | assert(predicate->is_Proj() && predicate->as_Proj()->is_IfProj(), "predicate must be a projection of an if node")do { if (!(predicate->is_Proj() && predicate->as_Proj ()->is_IfProj())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 341, "assert(" "predicate->is_Proj() && predicate->as_Proj()->is_IfProj()" ") failed", "predicate must be a projection of an if node"); ::breakpoint(); } } while (0); |
| 342 | IfProjNode* predicate_proj = predicate->as_IfProj(); |
| 343 | |
| 344 | ProjNode* fast_proj = clone_skeleton_predicate_for_unswitched_loops(iff, predicate_proj, reason, iffast_pred); |
| 345 | assert(skeleton_predicate_has_opaque(fast_proj->in(0)->as_If()), "must find skeleton predicate for fast loop")do { if (!(skeleton_predicate_has_opaque(fast_proj->in(0)-> as_If()))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 345, "assert(" "skeleton_predicate_has_opaque(fast_proj->in(0)->as_If())" ") failed", "must find skeleton predicate for fast loop"); :: breakpoint(); } } while (0); |
| 346 | ProjNode* slow_proj = clone_skeleton_predicate_for_unswitched_loops(iff, predicate_proj, reason, ifslow_pred); |
| 347 | assert(skeleton_predicate_has_opaque(slow_proj->in(0)->as_If()), "must find skeleton predicate for slow loop")do { if (!(skeleton_predicate_has_opaque(slow_proj->in(0)-> as_If()))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 347, "assert(" "skeleton_predicate_has_opaque(slow_proj->in(0)->as_If())" ") failed", "must find skeleton predicate for slow loop"); :: breakpoint(); } } while (0); |
| 348 | |
| 349 | // Update control dependent data nodes. |
| 350 | for (DUIterator j = predicate->outs(); predicate->has_out(j); j++) { |
| 351 | Node* fast_node = predicate->out(j); |
| 352 | if (loop->is_member(get_loop(ctrl_or_self(fast_node)))) { |
| 353 | assert(fast_node->in(0) == predicate, "only control edge")do { if (!(fast_node->in(0) == predicate)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 353, "assert(" "fast_node->in(0) == predicate" ") failed" , "only control edge"); ::breakpoint(); } } while (0); |
| 354 | Node* slow_node = old_new[fast_node->_idx]; |
| 355 | assert(slow_node->in(0) == predicate, "only control edge")do { if (!(slow_node->in(0) == predicate)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 355, "assert(" "slow_node->in(0) == predicate" ") failed" , "only control edge"); ::breakpoint(); } } while (0); |
| 356 | _igvn.replace_input_of(fast_node, 0, fast_proj); |
| 357 | to_process.push(slow_node); |
| 358 | --j; |
| 359 | } |
| 360 | } |
| 361 | // Have to delay updates to the slow loop so uses of predicate are not modified while we iterate on them. |
| 362 | while (to_process.size() > 0) { |
| 363 | Node* slow_node = to_process.pop(); |
| 364 | _igvn.replace_input_of(slow_node, 0, slow_proj); |
| 365 | } |
| 366 | } |
| 367 | } |
| 368 | |
| 369 | // Put all skeleton predicate projections on a list, starting at 'predicate' and going up in the tree. If 'get_opaque' |
| 370 | // is set, then the Opaque4 nodes of the skeleton predicates are put on the list instead of the projections. |
| 371 | void PhaseIdealLoop::get_skeleton_predicates(Node* predicate, Unique_Node_List& list, bool get_opaque) { |
| 372 | IfNode* iff = predicate->in(0)->as_If(); |
| 373 | ProjNode* uncommon_proj = iff->proj_out(1 - predicate->as_Proj()->_con); |
| 374 | Node* rgn = uncommon_proj->unique_ctrl_out(); |
| 375 | assert(rgn->is_Region() || rgn->is_Call(), "must be a region or call uct")do { if (!(rgn->is_Region() || rgn->is_Call())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 375, "assert(" "rgn->is_Region() || rgn->is_Call()" ") failed" , "must be a region or call uct"); ::breakpoint(); } } while ( 0); |
| 376 | assert(iff->in(1)->in(1)->Opcode() == Op_Opaque1, "unexpected predicate shape")do { if (!(iff->in(1)->in(1)->Opcode() == Op_Opaque1 )) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 376, "assert(" "iff->in(1)->in(1)->Opcode() == Op_Opaque1" ") failed", "unexpected predicate shape"); ::breakpoint(); } } while (0); |
| 377 | predicate = iff->in(0); |
| 378 | while (predicate != NULL__null && predicate->is_Proj() && predicate->in(0)->is_If()) { |
| 379 | iff = predicate->in(0)->as_If(); |
| 380 | uncommon_proj = iff->proj_out(1 - predicate->as_Proj()->_con); |
| 381 | if (uncommon_proj->unique_ctrl_out() != rgn) { |
| 382 | break; |
| 383 | } |
| 384 | if (iff->in(1)->Opcode() == Op_Opaque4 && skeleton_predicate_has_opaque(iff)) { |
| 385 | if (get_opaque) { |
| 386 | // Collect the predicate Opaque4 node. |
| 387 | list.push(iff->in(1)); |
| 388 | } else { |
| 389 | // Collect the predicate projection. |
| 390 | list.push(predicate); |
| 391 | } |
| 392 | } |
| 393 | predicate = predicate->in(0)->in(0); |
| 394 | } |
| 395 | } |
| 396 | |
| 397 | // Clone a skeleton predicate for an unswitched loop. OpaqueLoopInit and OpaqueLoopStride nodes are cloned and uncommon |
| 398 | // traps are kept for the predicate (a Halt node is used later when creating pre/main/post loops and copying this cloned |
| 399 | // predicate again). |
| 400 | ProjNode* PhaseIdealLoop::clone_skeleton_predicate_for_unswitched_loops(Node* iff, ProjNode* predicate, |
| 401 | Deoptimization::DeoptReason reason, |
| 402 | ProjNode* output_proj) { |
| 403 | Node* bol = clone_skeleton_predicate_bool(iff, NULL__null, NULL__null, output_proj); |
| 404 | ProjNode* proj = create_new_if_for_predicate(output_proj, NULL__null, reason, iff->Opcode(), predicate->is_IfTrue()); |
| 405 | _igvn.replace_input_of(proj->in(0), 1, bol); |
| 406 | _igvn.replace_input_of(output_proj->in(0), 0, proj); |
| 407 | set_idom(output_proj->in(0), proj, dom_depth(proj)); |
| 408 | return proj; |
| 409 | } |
| 410 | |
| 411 | //--------------------------clone_loop_predicates----------------------- |
| 412 | // Clone loop predicates to cloned loops when unswitching a loop. |
| 413 | void PhaseIdealLoop::clone_predicates_to_unswitched_loop(IdealLoopTree* loop, Node_List& old_new, ProjNode*& iffast_pred, ProjNode*& ifslow_pred) { |
| 414 | LoopNode* head = loop->_head->as_Loop(); |
| 415 | bool clone_limit_check = !head->is_CountedLoop(); |
| 416 | Node* entry = head->skip_strip_mined()->in(LoopNode::EntryControl); |
| 417 | |
| 418 | // Search original predicates |
| 419 | ProjNode* limit_check_proj = NULL__null; |
| 420 | limit_check_proj = find_predicate_insertion_point(entry, Deoptimization::Reason_loop_limit_check); |
| 421 | if (limit_check_proj != NULL__null) { |
| 422 | entry = skip_loop_predicates(entry); |
| 423 | } |
| 424 | ProjNode* profile_predicate_proj = NULL__null; |
| 425 | ProjNode* predicate_proj = NULL__null; |
| 426 | if (UseProfiledLoopPredicate) { |
| 427 | profile_predicate_proj = find_predicate_insertion_point(entry, Deoptimization::Reason_profile_predicate); |
| 428 | if (profile_predicate_proj != NULL__null) { |
| 429 | entry = skip_loop_predicates(entry); |
| 430 | } |
| 431 | } |
| 432 | if (UseLoopPredicate) { |
| 433 | predicate_proj = find_predicate_insertion_point(entry, Deoptimization::Reason_predicate); |
| 434 | } |
| 435 | if (predicate_proj != NULL__null) { // right pattern that can be used by loop predication |
| 436 | // clone predicate |
| 437 | iffast_pred = clone_predicate_to_unswitched_loop(predicate_proj, iffast_pred, Deoptimization::Reason_predicate, &old_new); |
| 438 | ifslow_pred = clone_predicate_to_unswitched_loop(predicate_proj, ifslow_pred, Deoptimization::Reason_predicate); |
| 439 | clone_skeleton_predicates_to_unswitched_loop(loop, old_new, Deoptimization::Reason_predicate, predicate_proj, iffast_pred, ifslow_pred); |
| 440 | |
| 441 | check_created_predicate_for_unswitching(iffast_pred); |
| 442 | check_created_predicate_for_unswitching(ifslow_pred); |
| 443 | } |
| 444 | if (profile_predicate_proj != NULL__null) { // right pattern that can be used by loop predication |
| 445 | // clone predicate |
| 446 | iffast_pred = clone_predicate_to_unswitched_loop(profile_predicate_proj, iffast_pred, Deoptimization::Reason_profile_predicate, &old_new); |
| 447 | ifslow_pred = clone_predicate_to_unswitched_loop(profile_predicate_proj, ifslow_pred, Deoptimization::Reason_profile_predicate); |
| 448 | clone_skeleton_predicates_to_unswitched_loop(loop, old_new, Deoptimization::Reason_profile_predicate, profile_predicate_proj, iffast_pred, ifslow_pred); |
| 449 | |
| 450 | check_created_predicate_for_unswitching(iffast_pred); |
| 451 | check_created_predicate_for_unswitching(ifslow_pred); |
| 452 | } |
| 453 | if (limit_check_proj != NULL__null && clone_limit_check) { |
| 454 | // Clone loop limit check last to insert it before loop. |
| 455 | // Don't clone a limit check which was already finalized |
| 456 | // for this counted loop (only one limit check is needed). |
| 457 | iffast_pred = clone_predicate_to_unswitched_loop(limit_check_proj, iffast_pred, Deoptimization::Reason_loop_limit_check, &old_new); |
| 458 | ifslow_pred = clone_predicate_to_unswitched_loop(limit_check_proj, ifslow_pred, Deoptimization::Reason_loop_limit_check); |
| 459 | |
| 460 | check_created_predicate_for_unswitching(iffast_pred); |
| 461 | check_created_predicate_for_unswitching(ifslow_pred); |
| 462 | } |
| 463 | } |
| 464 | |
| 465 | #ifndef PRODUCT |
| 466 | void PhaseIdealLoop::check_created_predicate_for_unswitching(const Node* new_entry) { |
| 467 | assert(new_entry != NULL, "IfTrue or IfFalse after clone predicate")do { if (!(new_entry != __null)) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 467, "assert(" "new_entry != __null" ") failed", "IfTrue or IfFalse after clone predicate" ); ::breakpoint(); } } while (0); |
| 468 | if (TraceLoopPredicate) { |
| 469 | tty->print("Loop Predicate cloned: "); |
| 470 | debug_only(new_entry->in(0)->dump();)new_entry->in(0)->dump();; |
| 471 | } |
| 472 | } |
| 473 | #endif |
| 474 | |
| 475 | |
| 476 | //--------------------------skip_loop_predicates------------------------------ |
| 477 | // Skip related predicates. |
| 478 | Node* PhaseIdealLoop::skip_loop_predicates(Node* entry) { |
| 479 | IfNode* iff = entry->in(0)->as_If(); |
| 480 | ProjNode* uncommon_proj = iff->proj_out(1 - entry->as_Proj()->_con); |
| 481 | Node* rgn = uncommon_proj->unique_ctrl_out(); |
| 482 | assert(rgn->is_Region() || rgn->is_Call(), "must be a region or call uct")do { if (!(rgn->is_Region() || rgn->is_Call())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 482, "assert(" "rgn->is_Region() || rgn->is_Call()" ") failed" , "must be a region or call uct"); ::breakpoint(); } } while ( 0); |
| 483 | entry = entry->in(0)->in(0); |
| 484 | while (entry != NULL__null && entry->is_Proj() && entry->in(0)->is_If()) { |
| 485 | uncommon_proj = entry->in(0)->as_If()->proj_out(1 - entry->as_Proj()->_con); |
| 486 | if (uncommon_proj->unique_ctrl_out() != rgn) |
| 487 | break; |
| 488 | entry = entry->in(0)->in(0); |
| 489 | } |
| 490 | return entry; |
| 491 | } |
| 492 | |
| 493 | Node* PhaseIdealLoop::skip_all_loop_predicates(Node* entry) { |
| 494 | Node* predicate = NULL__null; |
| 495 | predicate = find_predicate_insertion_point(entry, Deoptimization::Reason_loop_limit_check); |
| 496 | if (predicate != NULL__null) { |
| 497 | entry = skip_loop_predicates(entry); |
| 498 | } |
| 499 | if (UseProfiledLoopPredicate) { |
| 500 | predicate = find_predicate_insertion_point(entry, Deoptimization::Reason_profile_predicate); |
| 501 | if (predicate != NULL__null) { // right pattern that can be used by loop predication |
| 502 | entry = skip_loop_predicates(entry); |
| 503 | } |
| 504 | } |
| 505 | if (UseLoopPredicate) { |
| 506 | predicate = find_predicate_insertion_point(entry, Deoptimization::Reason_predicate); |
| 507 | if (predicate != NULL__null) { // right pattern that can be used by loop predication |
| 508 | entry = skip_loop_predicates(entry); |
| 509 | } |
| 510 | } |
| 511 | return entry; |
| 512 | } |
| 513 | |
| 514 | //--------------------------find_predicate_insertion_point------------------- |
| 515 | // Find a good location to insert a predicate |
| 516 | ProjNode* PhaseIdealLoop::find_predicate_insertion_point(Node* start_c, Deoptimization::DeoptReason reason) { |
| 517 | if (start_c == NULL__null || !start_c->is_Proj()) |
| 518 | return NULL__null; |
| 519 | if (start_c->as_Proj()->is_uncommon_trap_if_pattern(reason)) { |
| 520 | return start_c->as_Proj(); |
| 521 | } |
| 522 | return NULL__null; |
| 523 | } |
| 524 | |
| 525 | //--------------------------find_predicate------------------------------------ |
| 526 | // Find a predicate |
| 527 | Node* PhaseIdealLoop::find_predicate(Node* entry) { |
| 528 | Node* predicate = NULL__null; |
| 529 | predicate = find_predicate_insertion_point(entry, Deoptimization::Reason_loop_limit_check); |
| 530 | if (predicate != NULL__null) { // right pattern that can be used by loop predication |
| 531 | return entry; |
| 532 | } |
| 533 | if (UseLoopPredicate) { |
| 534 | predicate = find_predicate_insertion_point(entry, Deoptimization::Reason_predicate); |
| 535 | if (predicate != NULL__null) { // right pattern that can be used by loop predication |
| 536 | return entry; |
| 537 | } |
| 538 | } |
| 539 | if (UseProfiledLoopPredicate) { |
| 540 | predicate = find_predicate_insertion_point(entry, Deoptimization::Reason_profile_predicate); |
| 541 | if (predicate != NULL__null) { // right pattern that can be used by loop predication |
| 542 | return entry; |
| 543 | } |
| 544 | } |
| 545 | return NULL__null; |
| 546 | } |
| 547 | |
| 548 | //------------------------------Invariance----------------------------------- |
| 549 | // Helper class for loop_predication_impl to compute invariance on the fly and |
| 550 | // clone invariants. |
| 551 | class Invariance : public StackObj { |
| 552 | VectorSet _visited, _invariant; |
| 553 | Node_Stack _stack; |
| 554 | VectorSet _clone_visited; |
| 555 | Node_List _old_new; // map of old to new (clone) |
| 556 | IdealLoopTree* _lpt; |
| 557 | PhaseIdealLoop* _phase; |
| 558 | Node* _data_dependency_on; // The projection into the loop on which data nodes are dependent or NULL otherwise |
| 559 | |
| 560 | // Helper function to set up the invariance for invariance computation |
| 561 | // If n is a known invariant, set up directly. Otherwise, look up the |
| 562 | // the possibility to push n onto the stack for further processing. |
| 563 | void visit(Node* use, Node* n) { |
| 564 | if (_lpt->is_invariant(n)) { // known invariant |
| 565 | _invariant.set(n->_idx); |
| 566 | } else if (!n->is_CFG()) { |
| 567 | Node *n_ctrl = _phase->ctrl_or_self(n); |
| 568 | Node *u_ctrl = _phase->ctrl_or_self(use); // self if use is a CFG |
| 569 | if (_phase->is_dominator(n_ctrl, u_ctrl)) { |
| 570 | _stack.push(n, n->in(0) == NULL__null ? 1 : 0); |
| 571 | } |
| 572 | } |
| 573 | } |
| 574 | |
| 575 | // Compute invariance for "the_node" and (possibly) all its inputs recursively |
| 576 | // on the fly |
| 577 | void compute_invariance(Node* n) { |
| 578 | assert(_visited.test(n->_idx), "must be")do { if (!(_visited.test(n->_idx))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 578, "assert(" "_visited.test(n->_idx)" ") failed", "must be" ); ::breakpoint(); } } while (0); |
| 579 | visit(n, n); |
| 580 | while (_stack.is_nonempty()) { |
| 581 | Node* n = _stack.node(); |
| 582 | uint idx = _stack.index(); |
| 583 | if (idx == n->req()) { // all inputs are processed |
| 584 | _stack.pop(); |
| 585 | // n is invariant if it's inputs are all invariant |
| 586 | bool all_inputs_invariant = true; |
| 587 | for (uint i = 0; i < n->req(); i++) { |
| 588 | Node* in = n->in(i); |
| 589 | if (in == NULL__null) continue; |
| 590 | assert(_visited.test(in->_idx), "must have visited input")do { if (!(_visited.test(in->_idx))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 590, "assert(" "_visited.test(in->_idx)" ") failed", "must have visited input" ); ::breakpoint(); } } while (0); |
| 591 | if (!_invariant.test(in->_idx)) { // bad guy |
| 592 | all_inputs_invariant = false; |
| 593 | break; |
| 594 | } |
| 595 | } |
| 596 | if (all_inputs_invariant) { |
| 597 | // If n's control is a predicate that was moved out of the |
| 598 | // loop, it was marked invariant but n is only invariant if |
| 599 | // it depends only on that test. Otherwise, unless that test |
| 600 | // is out of the loop, it's not invariant. |
| 601 | if (n->is_CFG() || n->depends_only_on_test() || n->in(0) == NULL__null || !_phase->is_member(_lpt, n->in(0))) { |
| 602 | _invariant.set(n->_idx); // I am a invariant too |
| 603 | } |
| 604 | } |
| 605 | } else { // process next input |
| 606 | _stack.set_index(idx + 1); |
| 607 | Node* m = n->in(idx); |
| 608 | if (m != NULL__null && !_visited.test_set(m->_idx)) { |
| 609 | visit(n, m); |
| 610 | } |
| 611 | } |
| 612 | } |
| 613 | } |
| 614 | |
| 615 | // Helper function to set up _old_new map for clone_nodes. |
| 616 | // If n is a known invariant, set up directly ("clone" of n == n). |
| 617 | // Otherwise, push n onto the stack for real cloning. |
| 618 | void clone_visit(Node* n) { |
| 619 | assert(_invariant.test(n->_idx), "must be invariant")do { if (!(_invariant.test(n->_idx))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 619, "assert(" "_invariant.test(n->_idx)" ") failed", "must be invariant" ); ::breakpoint(); } } while (0); |
| 620 | if (_lpt->is_invariant(n)) { // known invariant |
| 621 | _old_new.map(n->_idx, n); |
| 622 | } else { // to be cloned |
| 623 | assert(!n->is_CFG(), "should not see CFG here")do { if (!(!n->is_CFG())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 623, "assert(" "!n->is_CFG()" ") failed", "should not see CFG here" ); ::breakpoint(); } } while (0); |
| 624 | _stack.push(n, n->in(0) == NULL__null ? 1 : 0); |
| 625 | } |
| 626 | } |
| 627 | |
| 628 | // Clone "n" and (possibly) all its inputs recursively |
| 629 | void clone_nodes(Node* n, Node* ctrl) { |
| 630 | clone_visit(n); |
| 631 | while (_stack.is_nonempty()) { |
| 632 | Node* n = _stack.node(); |
| 633 | uint idx = _stack.index(); |
| 634 | if (idx == n->req()) { // all inputs processed, clone n! |
| 635 | _stack.pop(); |
| 636 | // clone invariant node |
| 637 | Node* n_cl = n->clone(); |
| 638 | _old_new.map(n->_idx, n_cl); |
| 639 | _phase->register_new_node(n_cl, ctrl); |
| 640 | for (uint i = 0; i < n->req(); i++) { |
| 641 | Node* in = n_cl->in(i); |
| 642 | if (in == NULL__null) continue; |
| 643 | n_cl->set_req(i, _old_new[in->_idx]); |
| 644 | } |
| 645 | } else { // process next input |
| 646 | _stack.set_index(idx + 1); |
| 647 | Node* m = n->in(idx); |
| 648 | if (m != NULL__null && !_clone_visited.test_set(m->_idx)) { |
| 649 | clone_visit(m); // visit the input |
| 650 | } |
| 651 | } |
| 652 | } |
| 653 | } |
| 654 | |
| 655 | public: |
| 656 | Invariance(Arena* area, IdealLoopTree* lpt) : |
| 657 | _visited(area), _invariant(area), |
| 658 | _stack(area, 10 /* guess */), |
| 659 | _clone_visited(area), _old_new(area), |
| 660 | _lpt(lpt), _phase(lpt->_phase), |
| 661 | _data_dependency_on(NULL__null) |
| 662 | { |
| 663 | LoopNode* head = _lpt->_head->as_Loop(); |
| 664 | Node* entry = head->skip_strip_mined()->in(LoopNode::EntryControl); |
| 665 | if (entry->outcnt() != 1) { |
| 666 | // If a node is pinned between the predicates and the loop |
| 667 | // entry, we won't be able to move any node in the loop that |
| 668 | // depends on it above it in a predicate. Mark all those nodes |
| 669 | // as non-loop-invariant. |
| 670 | // Loop predication could create new nodes for which the below |
| 671 | // invariant information is missing. Mark the 'entry' node to |
| 672 | // later check again if a node needs to be treated as non-loop- |
| 673 | // invariant as well. |
| 674 | _data_dependency_on = entry; |
| 675 | Unique_Node_List wq; |
| 676 | wq.push(entry); |
| 677 | for (uint next = 0; next < wq.size(); ++next) { |
| 678 | Node *n = wq.at(next); |
| 679 | for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) { |
| 680 | Node* u = n->fast_out(i); |
| 681 | if (!u->is_CFG()) { |
| 682 | Node* c = _phase->get_ctrl(u); |
| 683 | if (_lpt->is_member(_phase->get_loop(c)) || _phase->is_dominator(c, head)) { |
| 684 | _visited.set(u->_idx); |
| 685 | wq.push(u); |
| 686 | } |
| 687 | } |
| 688 | } |
| 689 | } |
| 690 | } |
| 691 | } |
| 692 | |
| 693 | // Did we explicitly mark some nodes non-loop-invariant? If so, return the entry node on which some data nodes |
| 694 | // are dependent that prevent loop predication. Otherwise, return NULL. |
| 695 | Node* data_dependency_on() { |
| 696 | return _data_dependency_on; |
| 697 | } |
| 698 | |
| 699 | // Map old to n for invariance computation and clone |
| 700 | void map_ctrl(Node* old, Node* n) { |
| 701 | assert(old->is_CFG() && n->is_CFG(), "must be")do { if (!(old->is_CFG() && n->is_CFG())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 701, "assert(" "old->is_CFG() && n->is_CFG()" ") failed", "must be"); ::breakpoint(); } } while (0); |
| 702 | _old_new.map(old->_idx, n); // "clone" of old is n |
| 703 | _invariant.set(old->_idx); // old is invariant |
| 704 | _clone_visited.set(old->_idx); |
| 705 | } |
| 706 | |
| 707 | // Driver function to compute invariance |
| 708 | bool is_invariant(Node* n) { |
| 709 | if (!_visited.test_set(n->_idx)) |
| 710 | compute_invariance(n); |
| 711 | return (_invariant.test(n->_idx) != 0); |
| 712 | } |
| 713 | |
| 714 | // Driver function to clone invariant |
| 715 | Node* clone(Node* n, Node* ctrl) { |
| 716 | 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/loopPredicate.cpp" , 716, "assert(" "ctrl->is_CFG()" ") failed", "must be"); :: breakpoint(); } } while (0); |
| 717 | assert(_invariant.test(n->_idx), "must be an invariant")do { if (!(_invariant.test(n->_idx))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 717, "assert(" "_invariant.test(n->_idx)" ") failed", "must be an invariant" ); ::breakpoint(); } } while (0); |
| 718 | if (!_clone_visited.test(n->_idx)) |
| 719 | clone_nodes(n, ctrl); |
| 720 | return _old_new[n->_idx]; |
| 721 | } |
| 722 | }; |
| 723 | |
| 724 | //------------------------------is_range_check_if ----------------------------------- |
| 725 | // Returns true if the predicate of iff is in "scale*iv + offset u< load_range(ptr)" format |
| 726 | // Note: this function is particularly designed for loop predication. We require load_range |
| 727 | // and offset to be loop invariant computed on the fly by "invar" |
| 728 | bool IdealLoopTree::is_range_check_if(IfNode *iff, PhaseIdealLoop *phase, BasicType bt, Node *iv, Node *&range, |
| 729 | Node *&offset, jlong &scale) const { |
| 730 | if (!is_loop_exit(iff)) { |
| 731 | return false; |
| 732 | } |
| 733 | if (!iff->in(1)->is_Bool()) { |
| 734 | return false; |
| 735 | } |
| 736 | const BoolNode *bol = iff->in(1)->as_Bool(); |
| 737 | if (bol->_test._test != BoolTest::lt) { |
| 738 | return false; |
| 739 | } |
| 740 | if (!bol->in(1)->is_Cmp()) { |
| 741 | return false; |
| 742 | } |
| 743 | const CmpNode *cmp = bol->in(1)->as_Cmp(); |
| 744 | if (cmp->Opcode() != Op_Cmp_unsigned(bt)) { |
| 745 | return false; |
| 746 | } |
| 747 | range = cmp->in(2); |
| 748 | if (range->Opcode() != Op_LoadRange) { |
| 749 | const TypeInteger* tinteger = phase->_igvn.type(range)->isa_integer(bt); |
| 750 | if (tinteger == NULL__null || tinteger->empty() || tinteger->lo_as_long() < 0) { |
| 751 | // Allow predication on positive values that aren't LoadRanges. |
| 752 | // This allows optimization of loops where the length of the |
| 753 | // array is a known value and doesn't need to be loaded back |
| 754 | // from the array. |
| 755 | return false; |
| 756 | } |
| 757 | } else { |
| 758 | assert(bt == T_INT, "no LoadRange for longs")do { if (!(bt == T_INT)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 758, "assert(" "bt == T_INT" ") failed", "no LoadRange for longs" ); ::breakpoint(); } } while (0); |
| 759 | } |
| 760 | scale = 0; |
| 761 | offset = NULL__null; |
| 762 | if (!phase->is_scaled_iv_plus_offset(cmp->in(1), iv, &scale, &offset, bt)) { |
| 763 | return false; |
| 764 | } |
| 765 | return true; |
| 766 | } |
| 767 | |
| 768 | bool IdealLoopTree::is_range_check_if(IfNode *iff, PhaseIdealLoop *phase, Invariance& invar DEBUG_ONLY(COMMA ProjNode *predicate_proj), ProjNode *predicate_proj) const { |
| 769 | Node* range = NULL__null; |
| 770 | Node* offset = NULL__null; |
| 771 | jlong scale = 0; |
| 772 | Node* iv = _head->as_BaseCountedLoop()->phi(); |
| 773 | Compile* C = Compile::current(); |
| 774 | const uint old_unique_idx = C->unique(); |
| 775 | if (!is_range_check_if(iff, phase, T_INT, iv, range, offset, scale)) { |
| 776 | return false; |
| 777 | } |
| 778 | if (!invar.is_invariant(range)) { |
| 779 | return false; |
| 780 | } |
| 781 | if (offset != NULL__null) { |
| 782 | if (!invar.is_invariant(offset)) { // offset must be invariant |
| 783 | return false; |
| 784 | } |
| 785 | Node* data_dependency_on = invar.data_dependency_on(); |
| 786 | if (data_dependency_on != NULL__null && old_unique_idx < C->unique()) { |
| 787 | // 'offset' node was newly created in is_range_check_if(). Check that it does not depend on the entry projection |
| 788 | // into the loop. If it does, we cannot perform loop predication (see Invariant::Invariant()). |
| 789 | assert(!offset->is_CFG(), "offset must be a data node")do { if (!(!offset->is_CFG())) { (*g_assert_poison) = 'X'; ; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 789, "assert(" "!offset->is_CFG()" ") failed", "offset must be a data node" ); ::breakpoint(); } } while (0); |
| 790 | if (_phase->get_ctrl(offset) == data_dependency_on) { |
| 791 | return false; |
| 792 | } |
| 793 | } |
| 794 | } |
| 795 | #ifdef ASSERT1 |
| 796 | if (offset && phase->has_ctrl(offset)) { |
| 797 | Node* offset_ctrl = phase->get_ctrl(offset); |
| 798 | if (phase->get_loop(predicate_proj) == phase->get_loop(offset_ctrl) && |
| 799 | phase->is_dominator(predicate_proj, offset_ctrl)) { |
| 800 | // If the control of offset is loop predication promoted by previous pass, |
| 801 | // then it will lead to cyclic dependency. |
| 802 | // Previously promoted loop predication is in the same loop of predication |
| 803 | // point. |
| 804 | // This situation can occur when pinning nodes too conservatively - can we do better? |
| 805 | assert(false, "cyclic dependency prevents range check elimination, idx: offset %d, offset_ctrl %d, predicate_proj %d",do { if (!(false)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 806, "assert(" "false" ") failed", "cyclic dependency prevents range check elimination, idx: offset %d, offset_ctrl %d, predicate_proj %d" , offset->_idx, offset_ctrl->_idx, predicate_proj->_idx ); ::breakpoint(); } } while (0) |
| 806 | offset->_idx, offset_ctrl->_idx, predicate_proj->_idx)do { if (!(false)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 806, "assert(" "false" ") failed", "cyclic dependency prevents range check elimination, idx: offset %d, offset_ctrl %d, predicate_proj %d" , offset->_idx, offset_ctrl->_idx, predicate_proj->_idx ); ::breakpoint(); } } while (0); |
| 807 | } |
| 808 | } |
| 809 | #endif |
| 810 | return true; |
| 811 | } |
| 812 | |
| 813 | //------------------------------rc_predicate----------------------------------- |
| 814 | // Create a range check predicate |
| 815 | // |
| 816 | // for (i = init; i < limit; i += stride) { |
| 817 | // a[scale*i+offset] |
| 818 | // } |
| 819 | // |
| 820 | // Compute max(scale*i + offset) for init <= i < limit and build the predicate |
| 821 | // as "max(scale*i + offset) u< a.length". |
| 822 | // |
| 823 | // There are two cases for max(scale*i + offset): |
| 824 | // (1) stride*scale > 0 |
| 825 | // max(scale*i + offset) = scale*(limit-stride) + offset |
| 826 | // (2) stride*scale < 0 |
| 827 | // max(scale*i + offset) = scale*init + offset |
| 828 | BoolNode* PhaseIdealLoop::rc_predicate(IdealLoopTree *loop, Node* ctrl, |
| 829 | int scale, Node* offset, |
| 830 | Node* init, Node* limit, jint stride, |
| 831 | Node* range, bool upper, bool &overflow, bool negate) { |
| 832 | jint con_limit = (limit != NULL__null && limit->is_Con()) ? limit->get_int() : 0; |
| 833 | jint con_init = init->is_Con() ? init->get_int() : 0; |
| 834 | jint con_offset = offset->is_Con() ? offset->get_int() : 0; |
| 835 | |
| 836 | stringStream* predString = NULL__null; |
| 837 | if (TraceLoopPredicate) { |
| 838 | predString = new stringStream(); |
| 839 | predString->print("rc_predicate "); |
| 840 | } |
| 841 | |
| 842 | overflow = false; |
| 843 | Node* max_idx_expr = NULL__null; |
| 844 | const TypeInt* idx_type = TypeInt::INT; |
| 845 | if ((stride > 0) == (scale > 0) == upper) { |
| 846 | guarantee(limit != NULL, "sanity")do { if (!(limit != __null)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 846, "guarantee(" "limit != NULL" ") failed", "sanity"); :: breakpoint(); } } while (0); |
| 847 | if (TraceLoopPredicate) { |
| 848 | if (limit->is_Con()) { |
| 849 | predString->print("(%d ", con_limit); |
| 850 | } else { |
| 851 | predString->print("(limit "); |
| 852 | } |
| 853 | predString->print("- %d) ", stride); |
| 854 | } |
| 855 | // Check if (limit - stride) may overflow |
| 856 | const TypeInt* limit_type = _igvn.type(limit)->isa_int(); |
| 857 | jint limit_lo = limit_type->_lo; |
| 858 | jint limit_hi = limit_type->_hi; |
| 859 | if ((stride > 0 && (java_subtract(limit_lo, stride) < limit_lo)) || |
| 860 | (stride < 0 && (java_subtract(limit_hi, stride) > limit_hi))) { |
| 861 | // No overflow possible |
| 862 | ConINode* con_stride = _igvn.intcon(stride); |
| 863 | set_ctrl(con_stride, C->root()); |
| 864 | max_idx_expr = new SubINode(limit, con_stride); |
| 865 | idx_type = TypeInt::make(limit_lo - stride, limit_hi - stride, limit_type->_widen); |
| 866 | } else { |
| 867 | // May overflow |
| 868 | overflow = true; |
| 869 | limit = new ConvI2LNode(limit); |
| 870 | register_new_node(limit, ctrl); |
| 871 | ConLNode* con_stride = _igvn.longcon(stride); |
| 872 | set_ctrl(con_stride, C->root()); |
| 873 | max_idx_expr = new SubLNode(limit, con_stride); |
| 874 | } |
| 875 | register_new_node(max_idx_expr, ctrl); |
| 876 | } else { |
| 877 | if (TraceLoopPredicate) { |
| 878 | if (init->is_Con()) { |
| 879 | predString->print("%d ", con_init); |
| 880 | } else { |
| 881 | predString->print("init "); |
| 882 | } |
| 883 | } |
| 884 | idx_type = _igvn.type(init)->isa_int(); |
| 885 | max_idx_expr = init; |
| 886 | } |
| 887 | |
| 888 | if (scale != 1) { |
| 889 | ConNode* con_scale = _igvn.intcon(scale); |
| 890 | set_ctrl(con_scale, C->root()); |
| 891 | if (TraceLoopPredicate) { |
| 892 | predString->print("* %d ", scale); |
| 893 | } |
| 894 | // Check if (scale * max_idx_expr) may overflow |
| 895 | const TypeInt* scale_type = TypeInt::make(scale); |
| 896 | MulINode* mul = new MulINode(max_idx_expr, con_scale); |
| 897 | idx_type = (TypeInt*)mul->mul_ring(idx_type, scale_type); |
| 898 | if (overflow || TypeInt::INT->higher_equal(idx_type)) { |
| 899 | // May overflow |
| 900 | mul->destruct(&_igvn); |
| 901 | if (!overflow) { |
| 902 | max_idx_expr = new ConvI2LNode(max_idx_expr); |
| 903 | register_new_node(max_idx_expr, ctrl); |
| 904 | } |
| 905 | overflow = true; |
| 906 | con_scale = _igvn.longcon(scale); |
| 907 | set_ctrl(con_scale, C->root()); |
| 908 | max_idx_expr = new MulLNode(max_idx_expr, con_scale); |
| 909 | } else { |
| 910 | // No overflow possible |
| 911 | max_idx_expr = mul; |
| 912 | } |
| 913 | register_new_node(max_idx_expr, ctrl); |
| 914 | } |
| 915 | |
| 916 | if (offset && (!offset->is_Con() || con_offset != 0)){ |
| 917 | if (TraceLoopPredicate) { |
| 918 | if (offset->is_Con()) { |
| 919 | predString->print("+ %d ", con_offset); |
| 920 | } else { |
| 921 | predString->print("+ offset"); |
| 922 | } |
| 923 | } |
| 924 | // Check if (max_idx_expr + offset) may overflow |
| 925 | const TypeInt* offset_type = _igvn.type(offset)->isa_int(); |
| 926 | jint lo = java_add(idx_type->_lo, offset_type->_lo); |
| 927 | jint hi = java_add(idx_type->_hi, offset_type->_hi); |
| 928 | if (overflow || (lo > hi) || |
| 929 | ((idx_type->_lo & offset_type->_lo) < 0 && lo >= 0) || |
| 930 | ((~(idx_type->_hi | offset_type->_hi)) < 0 && hi < 0)) { |
| 931 | // May overflow |
| 932 | if (!overflow) { |
| 933 | max_idx_expr = new ConvI2LNode(max_idx_expr); |
| 934 | register_new_node(max_idx_expr, ctrl); |
| 935 | } |
| 936 | overflow = true; |
| 937 | offset = new ConvI2LNode(offset); |
| 938 | register_new_node(offset, ctrl); |
| 939 | max_idx_expr = new AddLNode(max_idx_expr, offset); |
| 940 | } else { |
| 941 | // No overflow possible |
| 942 | max_idx_expr = new AddINode(max_idx_expr, offset); |
| 943 | } |
| 944 | register_new_node(max_idx_expr, ctrl); |
| 945 | } |
| 946 | |
| 947 | CmpNode* cmp = NULL__null; |
| 948 | if (overflow) { |
| 949 | // Integer expressions may overflow, do long comparison |
| 950 | range = new ConvI2LNode(range); |
| 951 | register_new_node(range, ctrl); |
| 952 | cmp = new CmpULNode(max_idx_expr, range); |
| 953 | } else { |
| 954 | cmp = new CmpUNode(max_idx_expr, range); |
| 955 | } |
| 956 | register_new_node(cmp, ctrl); |
| 957 | BoolNode* bol = new BoolNode(cmp, negate ? BoolTest::ge : BoolTest::lt); |
| 958 | register_new_node(bol, ctrl); |
| 959 | |
| 960 | if (TraceLoopPredicate) { |
| 961 | predString->print_cr("<u range"); |
| 962 | tty->print("%s", predString->base()); |
| 963 | predString->~stringStream(); |
| 964 | } |
| 965 | return bol; |
| 966 | } |
| 967 | |
| 968 | // Should loop predication look not only in the path from tail to head |
| 969 | // but also in branches of the loop body? |
| 970 | bool PhaseIdealLoop::loop_predication_should_follow_branches(IdealLoopTree *loop, ProjNode *predicate_proj, float& loop_trip_cnt) { |
| 971 | if (!UseProfiledLoopPredicate) { |
| 972 | return false; |
| 973 | } |
| 974 | |
| 975 | if (predicate_proj == NULL__null) { |
| 976 | return false; |
| 977 | } |
| 978 | |
| 979 | LoopNode* head = loop->_head->as_Loop(); |
| 980 | bool follow_branches = true; |
| 981 | IdealLoopTree* l = loop->_child; |
| 982 | // For leaf loops and loops with a single inner loop |
| 983 | while (l != NULL__null && follow_branches) { |
| 984 | IdealLoopTree* child = l; |
| 985 | if (child->_child != NULL__null && |
| 986 | child->_head->is_OuterStripMinedLoop()) { |
| 987 | assert(child->_child->_next == NULL, "only one inner loop for strip mined loop")do { if (!(child->_child->_next == __null)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 987, "assert(" "child->_child->_next == __null" ") failed" , "only one inner loop for strip mined loop"); ::breakpoint() ; } } while (0); |
| 988 | assert(child->_child->_head->is_CountedLoop() && child->_child->_head->as_CountedLoop()->is_strip_mined(), "inner loop should be strip mined")do { if (!(child->_child->_head->is_CountedLoop() && child->_child->_head->as_CountedLoop()->is_strip_mined ())) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 988, "assert(" "child->_child->_head->is_CountedLoop() && child->_child->_head->as_CountedLoop()->is_strip_mined()" ") failed", "inner loop should be strip mined"); ::breakpoint (); } } while (0); |
| 989 | child = child->_child; |
| 990 | } |
| 991 | if (child->_child != NULL__null || child->_irreducible) { |
| 992 | follow_branches = false; |
| 993 | } |
| 994 | l = l->_next; |
| 995 | } |
| 996 | if (follow_branches) { |
| 997 | loop->compute_profile_trip_cnt(this); |
| 998 | if (head->is_profile_trip_failed()) { |
| 999 | follow_branches = false; |
| 1000 | } else { |
| 1001 | loop_trip_cnt = head->profile_trip_cnt(); |
| 1002 | if (head->is_CountedLoop()) { |
| 1003 | CountedLoopNode* cl = head->as_CountedLoop(); |
| 1004 | if (cl->phi() != NULL__null) { |
| 1005 | const TypeInt* t = _igvn.type(cl->phi())->is_int(); |
| 1006 | float worst_case_trip_cnt = ((float)t->_hi - t->_lo) / ABS(cl->stride_con()); |
| 1007 | if (worst_case_trip_cnt < loop_trip_cnt) { |
| 1008 | loop_trip_cnt = worst_case_trip_cnt; |
| 1009 | } |
| 1010 | } |
| 1011 | } |
| 1012 | } |
| 1013 | } |
| 1014 | return follow_branches; |
| 1015 | } |
| 1016 | |
| 1017 | // Compute probability of reaching some CFG node from a fixed |
| 1018 | // dominating CFG node |
| 1019 | class PathFrequency { |
| 1020 | private: |
| 1021 | Node* _dom; // frequencies are computed relative to this node |
| 1022 | Node_Stack _stack; |
| 1023 | GrowableArray<float> _freqs_stack; // keep track of intermediate result at regions |
| 1024 | GrowableArray<float> _freqs; // cache frequencies |
| 1025 | PhaseIdealLoop* _phase; |
| 1026 | |
| 1027 | void set_rounding(int mode) { |
| 1028 | // fesetround is broken on windows |
| 1029 | NOT_WINDOWS(fesetround(mode);)fesetround(mode); |
| 1030 | } |
| 1031 | |
| 1032 | void check_frequency(float f) { |
| 1033 | NOT_WINDOWS(assert(f <= 1 && f >= 0, "Incorrect frequency");)do { if (!(f <= 1 && f >= 0)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1033, "assert(" "f <= 1 && f >= 0" ") failed" , "Incorrect frequency"); ::breakpoint(); } } while (0); |
| 1034 | } |
| 1035 | |
| 1036 | public: |
| 1037 | PathFrequency(Node* dom, PhaseIdealLoop* phase) |
| 1038 | : _dom(dom), _stack(0), _phase(phase) { |
| 1039 | } |
| 1040 | |
| 1041 | float to(Node* n) { |
| 1042 | // post order walk on the CFG graph from n to _dom |
| 1043 | set_rounding(FE_TOWARDZERO0xc00); // make sure rounding doesn't push frequency above 1 |
| 1044 | IdealLoopTree* loop = _phase->get_loop(_dom); |
| 1045 | Node* c = n; |
| 1046 | for (;;) { |
| 1047 | assert(_phase->get_loop(c) == loop, "have to be in the same loop")do { if (!(_phase->get_loop(c) == loop)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1047, "assert(" "_phase->get_loop(c) == loop" ") failed" , "have to be in the same loop"); ::breakpoint(); } } while ( 0); |
| 1048 | if (c == _dom || _freqs.at_grow(c->_idx, -1) >= 0) { |
| 1049 | float f = c == _dom ? 1 : _freqs.at(c->_idx); |
| 1050 | Node* prev = c; |
| 1051 | while (_stack.size() > 0 && prev == c) { |
| 1052 | Node* n = _stack.node(); |
| 1053 | if (!n->is_Region()) { |
| 1054 | if (_phase->get_loop(n) != _phase->get_loop(n->in(0))) { |
| 1055 | // Found an inner loop: compute frequency of reaching this |
| 1056 | // exit from the loop head by looking at the number of |
| 1057 | // times each loop exit was taken |
| 1058 | IdealLoopTree* inner_loop = _phase->get_loop(n->in(0)); |
| 1059 | LoopNode* inner_head = inner_loop->_head->as_Loop(); |
| 1060 | assert(_phase->get_loop(n) == loop, "only 1 inner loop")do { if (!(_phase->get_loop(n) == loop)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1060, "assert(" "_phase->get_loop(n) == loop" ") failed" , "only 1 inner loop"); ::breakpoint(); } } while (0); |
| 1061 | if (inner_head->is_OuterStripMinedLoop()) { |
| 1062 | inner_head->verify_strip_mined(1); |
| 1063 | if (n->in(0) == inner_head->in(LoopNode::LoopBackControl)->in(0)) { |
| 1064 | n = n->in(0)->in(0)->in(0); |
| 1065 | } |
| 1066 | inner_loop = inner_loop->_child; |
| 1067 | inner_head = inner_loop->_head->as_Loop(); |
| 1068 | inner_head->verify_strip_mined(1); |
| 1069 | } |
| 1070 | set_rounding(FE_UPWARD0x800); // make sure rounding doesn't push frequency above 1 |
| 1071 | float loop_exit_cnt = 0.0f; |
| 1072 | for (uint i = 0; i < inner_loop->_body.size(); i++) { |
| 1073 | Node *n = inner_loop->_body[i]; |
| 1074 | float c = inner_loop->compute_profile_trip_cnt_helper(n); |
| 1075 | loop_exit_cnt += c; |
| 1076 | } |
| 1077 | set_rounding(FE_TOWARDZERO0xc00); |
| 1078 | float cnt = -1; |
| 1079 | if (n->in(0)->is_If()) { |
| 1080 | IfNode* iff = n->in(0)->as_If(); |
| 1081 | float p = n->in(0)->as_If()->_prob; |
| 1082 | if (n->Opcode() == Op_IfFalse) { |
| 1083 | p = 1 - p; |
| 1084 | } |
| 1085 | if (p > PROB_MIN(1e-6f)) { |
| 1086 | cnt = p * iff->_fcnt; |
| 1087 | } else { |
| 1088 | cnt = 0; |
| 1089 | } |
| 1090 | } else { |
| 1091 | assert(n->in(0)->is_Jump(), "unsupported node kind")do { if (!(n->in(0)->is_Jump())) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1091, "assert(" "n->in(0)->is_Jump()" ") failed", "unsupported node kind" ); ::breakpoint(); } } while (0); |
| 1092 | JumpNode* jmp = n->in(0)->as_Jump(); |
| 1093 | float p = n->in(0)->as_Jump()->_probs[n->as_JumpProj()->_con]; |
| 1094 | cnt = p * jmp->_fcnt; |
| 1095 | } |
| 1096 | float this_exit_f = cnt > 0 ? cnt / loop_exit_cnt : 0; |
| 1097 | check_frequency(this_exit_f); |
| 1098 | f = f * this_exit_f; |
| 1099 | check_frequency(f); |
| 1100 | } else { |
| 1101 | float p = -1; |
| 1102 | if (n->in(0)->is_If()) { |
| 1103 | p = n->in(0)->as_If()->_prob; |
| 1104 | if (n->Opcode() == Op_IfFalse) { |
| 1105 | p = 1 - p; |
| 1106 | } |
| 1107 | } else { |
| 1108 | assert(n->in(0)->is_Jump(), "unsupported node kind")do { if (!(n->in(0)->is_Jump())) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1108, "assert(" "n->in(0)->is_Jump()" ") failed", "unsupported node kind" ); ::breakpoint(); } } while (0); |
| 1109 | p = n->in(0)->as_Jump()->_probs[n->as_JumpProj()->_con]; |
| 1110 | } |
| 1111 | f = f * p; |
| 1112 | check_frequency(f); |
| 1113 | } |
| 1114 | _freqs.at_put_grow(n->_idx, (float)f, -1); |
| 1115 | _stack.pop(); |
| 1116 | } else { |
| 1117 | float prev_f = _freqs_stack.pop(); |
| 1118 | float new_f = f; |
| 1119 | f = new_f + prev_f; |
| 1120 | check_frequency(f); |
| 1121 | uint i = _stack.index(); |
| 1122 | if (i < n->req()) { |
| 1123 | c = n->in(i); |
| 1124 | _stack.set_index(i+1); |
| 1125 | _freqs_stack.push(f); |
| 1126 | } else { |
| 1127 | _freqs.at_put_grow(n->_idx, f, -1); |
| 1128 | _stack.pop(); |
| 1129 | } |
| 1130 | } |
| 1131 | } |
| 1132 | if (_stack.size() == 0) { |
| 1133 | set_rounding(FE_TONEAREST0); |
| 1134 | check_frequency(f); |
| 1135 | return f; |
| 1136 | } |
| 1137 | } else if (c->is_Loop()) { |
| 1138 | ShouldNotReachHere()do { (*g_assert_poison) = 'X';; report_should_not_reach_here( "/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1138); ::breakpoint(); } while (0); |
| 1139 | c = c->in(LoopNode::EntryControl); |
| 1140 | } else if (c->is_Region()) { |
| 1141 | _freqs_stack.push(0); |
| 1142 | _stack.push(c, 2); |
| 1143 | c = c->in(1); |
| 1144 | } else { |
| 1145 | if (c->is_IfProj()) { |
| 1146 | IfNode* iff = c->in(0)->as_If(); |
| 1147 | if (iff->_prob == PROB_UNKNOWN(-1.0f)) { |
| 1148 | // assume never taken |
| 1149 | _freqs.at_put_grow(c->_idx, 0, -1); |
| 1150 | } else if (_phase->get_loop(c) != _phase->get_loop(iff)) { |
| 1151 | if (iff->_fcnt == COUNT_UNKNOWN(-1.0f)) { |
| 1152 | // assume never taken |
| 1153 | _freqs.at_put_grow(c->_idx, 0, -1); |
| 1154 | } else { |
| 1155 | // skip over loop |
| 1156 | _stack.push(c, 1); |
| 1157 | c = _phase->get_loop(c->in(0))->_head->as_Loop()->skip_strip_mined()->in(LoopNode::EntryControl); |
| 1158 | } |
| 1159 | } else { |
| 1160 | _stack.push(c, 1); |
| 1161 | c = iff; |
| 1162 | } |
| 1163 | } else if (c->is_JumpProj()) { |
| 1164 | JumpNode* jmp = c->in(0)->as_Jump(); |
| 1165 | if (_phase->get_loop(c) != _phase->get_loop(jmp)) { |
| 1166 | if (jmp->_fcnt == COUNT_UNKNOWN(-1.0f)) { |
| 1167 | // assume never taken |
| 1168 | _freqs.at_put_grow(c->_idx, 0, -1); |
| 1169 | } else { |
| 1170 | // skip over loop |
| 1171 | _stack.push(c, 1); |
| 1172 | c = _phase->get_loop(c->in(0))->_head->as_Loop()->skip_strip_mined()->in(LoopNode::EntryControl); |
| 1173 | } |
| 1174 | } else { |
| 1175 | _stack.push(c, 1); |
| 1176 | c = jmp; |
| 1177 | } |
| 1178 | } else if (c->Opcode() == Op_CatchProj && |
| 1179 | c->in(0)->Opcode() == Op_Catch && |
| 1180 | c->in(0)->in(0)->is_Proj() && |
| 1181 | c->in(0)->in(0)->in(0)->is_Call()) { |
| 1182 | // assume exceptions are never thrown |
| 1183 | uint con = c->as_Proj()->_con; |
| 1184 | if (con == CatchProjNode::fall_through_index) { |
| 1185 | Node* call = c->in(0)->in(0)->in(0)->in(0); |
| 1186 | if (_phase->get_loop(call) != _phase->get_loop(c)) { |
| 1187 | _freqs.at_put_grow(c->_idx, 0, -1); |
| 1188 | } else { |
| 1189 | c = call; |
| 1190 | } |
| 1191 | } else { |
| 1192 | assert(con >= CatchProjNode::catch_all_index, "what else?")do { if (!(con >= CatchProjNode::catch_all_index)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1192, "assert(" "con >= CatchProjNode::catch_all_index" ") failed" , "what else?"); ::breakpoint(); } } while (0); |
| 1193 | _freqs.at_put_grow(c->_idx, 0, -1); |
| 1194 | } |
| 1195 | } else if (c->unique_ctrl_out() == NULL__null && !c->is_If() && !c->is_Jump()) { |
| 1196 | ShouldNotReachHere()do { (*g_assert_poison) = 'X';; report_should_not_reach_here( "/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1196); ::breakpoint(); } while (0); |
| 1197 | } else { |
| 1198 | c = c->in(0); |
| 1199 | } |
| 1200 | } |
| 1201 | } |
| 1202 | ShouldNotReachHere()do { (*g_assert_poison) = 'X';; report_should_not_reach_here( "/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1202); ::breakpoint(); } while (0); |
| 1203 | return -1; |
| 1204 | } |
| 1205 | }; |
| 1206 | |
| 1207 | void PhaseIdealLoop::loop_predication_follow_branches(Node *n, IdealLoopTree *loop, float loop_trip_cnt, |
| 1208 | PathFrequency& pf, Node_Stack& stack, VectorSet& seen, |
| 1209 | Node_List& if_proj_list) { |
| 1210 | assert(n->is_Region(), "start from a region")do { if (!(n->is_Region())) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1210, "assert(" "n->is_Region()" ") failed", "start from a region" ); ::breakpoint(); } } while (0); |
| 1211 | Node* tail = loop->tail(); |
| 1212 | stack.push(n, 1); |
| 1213 | do { |
| 1214 | Node* c = stack.node(); |
| 1215 | assert(c->is_Region() || c->is_IfProj(), "only region here")do { if (!(c->is_Region() || c->is_IfProj())) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1215, "assert(" "c->is_Region() || c->is_IfProj()" ") failed" , "only region here"); ::breakpoint(); } } while (0); |
| 1216 | uint i = stack.index(); |
| 1217 | |
| 1218 | if (i < c->req()) { |
| 1219 | stack.set_index(i+1); |
| 1220 | Node* in = c->in(i); |
| 1221 | while (!is_dominator(in, tail) && !seen.test_set(in->_idx)) { |
| 1222 | IdealLoopTree* in_loop = get_loop(in); |
| 1223 | if (in_loop != loop) { |
| 1224 | in = in_loop->_head->in(LoopNode::EntryControl); |
| 1225 | } else if (in->is_Region()) { |
| 1226 | stack.push(in, 1); |
| 1227 | break; |
| 1228 | } else if (in->is_IfProj() && |
| 1229 | in->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none) && |
| 1230 | (in->in(0)->Opcode() == Op_If || |
| 1231 | in->in(0)->Opcode() == Op_RangeCheck)) { |
| 1232 | if (pf.to(in) * loop_trip_cnt >= 1) { |
| 1233 | stack.push(in, 1); |
| 1234 | } |
| 1235 | in = in->in(0); |
| 1236 | } else { |
| 1237 | in = in->in(0); |
| 1238 | } |
| 1239 | } |
| 1240 | } else { |
| 1241 | if (c->is_IfProj()) { |
| 1242 | if_proj_list.push(c); |
| 1243 | } |
| 1244 | stack.pop(); |
| 1245 | } |
| 1246 | |
| 1247 | } while (stack.size() > 0); |
| 1248 | } |
| 1249 | |
| 1250 | |
| 1251 | bool PhaseIdealLoop::loop_predication_impl_helper(IdealLoopTree *loop, ProjNode* proj, ProjNode *predicate_proj, |
| 1252 | CountedLoopNode *cl, ConNode* zero, Invariance& invar, |
| 1253 | Deoptimization::DeoptReason reason) { |
| 1254 | // Following are changed to nonnull when a predicate can be hoisted |
| 1255 | ProjNode* new_predicate_proj = NULL__null; |
| 1256 | IfNode* iff = proj->in(0)->as_If(); |
| 1257 | Node* test = iff->in(1); |
| 1258 | if (!test->is_Bool()){ //Conv2B, ... |
| 1259 | return false; |
| 1260 | } |
| 1261 | BoolNode* bol = test->as_Bool(); |
| 1262 | if (invar.is_invariant(bol)) { |
| 1263 | // Invariant test |
| 1264 | new_predicate_proj = create_new_if_for_predicate(predicate_proj, NULL__null, |
| 1265 | reason, |
| 1266 | iff->Opcode()); |
| 1267 | Node* ctrl = new_predicate_proj->in(0)->as_If()->in(0); |
| 1268 | BoolNode* new_predicate_bol = invar.clone(bol, ctrl)->as_Bool(); |
| 1269 | |
| 1270 | // Negate test if necessary |
| 1271 | bool negated = false; |
| 1272 | if (proj->_con != predicate_proj->_con) { |
| 1273 | new_predicate_bol = new BoolNode(new_predicate_bol->in(1), new_predicate_bol->_test.negate()); |
| 1274 | register_new_node(new_predicate_bol, ctrl); |
| 1275 | negated = true; |
| 1276 | } |
| 1277 | IfNode* new_predicate_iff = new_predicate_proj->in(0)->as_If(); |
| 1278 | _igvn.hash_delete(new_predicate_iff); |
| 1279 | new_predicate_iff->set_req(1, new_predicate_bol); |
| 1280 | #ifndef PRODUCT |
| 1281 | if (TraceLoopPredicate) { |
| 1282 | tty->print("Predicate invariant if%s: %d ", negated ? " negated" : "", new_predicate_iff->_idx); |
| 1283 | loop->dump_head(); |
| 1284 | } else if (TraceLoopOpts) { |
| 1285 | tty->print("Predicate IC "); |
| 1286 | loop->dump_head(); |
| 1287 | } |
| 1288 | #endif |
| 1289 | } else if (cl != NULL__null && loop->is_range_check_if(iff, this, invar DEBUG_ONLY(COMMA predicate_proj), predicate_proj)) { |
| 1290 | // Range check for counted loops |
| 1291 | const Node* cmp = bol->in(1)->as_Cmp(); |
| 1292 | Node* idx = cmp->in(1); |
| 1293 | assert(!invar.is_invariant(idx), "index is variant")do { if (!(!invar.is_invariant(idx))) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1293, "assert(" "!invar.is_invariant(idx)" ") failed", "index is variant" ); ::breakpoint(); } } while (0); |
| 1294 | Node* rng = cmp->in(2); |
| 1295 | assert(rng->Opcode() == Op_LoadRange || iff->is_RangeCheck() || _igvn.type(rng)->is_int()->_lo >= 0, "must be")do { if (!(rng->Opcode() == Op_LoadRange || iff->is_RangeCheck () || _igvn.type(rng)->is_int()->_lo >= 0)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1295, "assert(" "rng->Opcode() == Op_LoadRange || iff->is_RangeCheck() || _igvn.type(rng)->is_int()->_lo >= 0" ") failed", "must be"); ::breakpoint(); } } while (0); |
| 1296 | assert(invar.is_invariant(rng), "range must be invariant")do { if (!(invar.is_invariant(rng))) { (*g_assert_poison) = 'X' ;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1296, "assert(" "invar.is_invariant(rng)" ") failed", "range must be invariant" ); ::breakpoint(); } } while (0); |
| 1297 | int scale = 1; |
| 1298 | Node* offset = zero; |
| 1299 | bool ok = is_scaled_iv_plus_offset(idx, cl->phi(), &scale, &offset); |
| 1300 | assert(ok, "must be index expression")do { if (!(ok)) { (*g_assert_poison) = 'X';; report_vm_error( "/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1300, "assert(" "ok" ") failed", "must be index expression" ); ::breakpoint(); } } while (0); |
| 1301 | |
| 1302 | Node* init = cl->init_trip(); |
| 1303 | // Limit is not exact. |
| 1304 | // Calculate exact limit here. |
| 1305 | // Note, counted loop's test is '<' or '>'. |
| 1306 | loop->compute_trip_count(this); |
| 1307 | Node* limit = exact_limit(loop); |
| 1308 | int stride = cl->stride()->get_int(); |
| 1309 | |
| 1310 | // Build if's for the upper and lower bound tests. The |
| 1311 | // lower_bound test will dominate the upper bound test and all |
| 1312 | // cloned or created nodes will use the lower bound test as |
| 1313 | // their declared control. |
| 1314 | |
| 1315 | // Perform cloning to keep Invariance state correct since the |
| 1316 | // late schedule will place invariant things in the loop. |
| 1317 | Node *ctrl = predicate_proj->in(0)->as_If()->in(0); |
| 1318 | rng = invar.clone(rng, ctrl); |
| 1319 | if (offset && offset != zero) { |
| 1320 | assert(invar.is_invariant(offset), "offset must be loop invariant")do { if (!(invar.is_invariant(offset))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1320, "assert(" "invar.is_invariant(offset)" ") failed", "offset must be loop invariant" ); ::breakpoint(); } } while (0); |
| 1321 | offset = invar.clone(offset, ctrl); |
| 1322 | } |
| 1323 | // If predicate expressions may overflow in the integer range, longs are used. |
| 1324 | bool overflow = false; |
| 1325 | bool negate = (proj->_con != predicate_proj->_con); |
| 1326 | |
| 1327 | // Test the lower bound |
| 1328 | BoolNode* lower_bound_bol = rc_predicate(loop, ctrl, scale, offset, init, limit, stride, rng, false, overflow, negate); |
| 1329 | |
| 1330 | ProjNode* lower_bound_proj = create_new_if_for_predicate(predicate_proj, NULL__null, reason, overflow ? Op_If : iff->Opcode()); |
| 1331 | IfNode* lower_bound_iff = lower_bound_proj->in(0)->as_If(); |
| 1332 | _igvn.hash_delete(lower_bound_iff); |
| 1333 | lower_bound_iff->set_req(1, lower_bound_bol); |
| 1334 | if (TraceLoopPredicate) tty->print_cr("lower bound check if: %s %d ", negate ? " negated" : "", lower_bound_iff->_idx); |
| 1335 | |
| 1336 | // Test the upper bound |
| 1337 | BoolNode* upper_bound_bol = rc_predicate(loop, lower_bound_proj, scale, offset, init, limit, stride, rng, true, overflow, negate); |
| 1338 | |
| 1339 | ProjNode* upper_bound_proj = create_new_if_for_predicate(predicate_proj, NULL__null, reason, overflow ? Op_If : iff->Opcode()); |
| 1340 | assert(upper_bound_proj->in(0)->as_If()->in(0) == lower_bound_proj, "should dominate")do { if (!(upper_bound_proj->in(0)->as_If()->in(0) == lower_bound_proj)) { (*g_assert_poison) = 'X';; report_vm_error ("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1340, "assert(" "upper_bound_proj->in(0)->as_If()->in(0) == lower_bound_proj" ") failed", "should dominate"); ::breakpoint(); } } while (0 ); |
| 1341 | IfNode* upper_bound_iff = upper_bound_proj->in(0)->as_If(); |
| 1342 | _igvn.hash_delete(upper_bound_iff); |
| 1343 | upper_bound_iff->set_req(1, upper_bound_bol); |
| 1344 | if (TraceLoopPredicate) tty->print_cr("upper bound check if: %s %d ", negate ? " negated" : "", lower_bound_iff->_idx); |
| 1345 | |
| 1346 | // Fall through into rest of the clean up code which will move |
| 1347 | // any dependent nodes onto the upper bound test. |
| 1348 | new_predicate_proj = upper_bound_proj; |
| 1349 | |
| 1350 | if (iff->is_RangeCheck()) { |
| 1351 | new_predicate_proj = insert_initial_skeleton_predicate(iff, loop, proj, predicate_proj, upper_bound_proj, scale, offset, init, limit, stride, rng, overflow, reason); |
| 1352 | } |
| 1353 | |
| 1354 | #ifndef PRODUCT |
| 1355 | if (TraceLoopOpts && !TraceLoopPredicate) { |
| 1356 | tty->print("Predicate RC "); |
| 1357 | loop->dump_head(); |
| 1358 | } |
| 1359 | #endif |
| 1360 | } else { |
| 1361 | // Loop variant check (for example, range check in non-counted loop) |
| 1362 | // with uncommon trap. |
| 1363 | return false; |
| 1364 | } |
| 1365 | assert(new_predicate_proj != NULL, "sanity")do { if (!(new_predicate_proj != __null)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1365, "assert(" "new_predicate_proj != __null" ") failed", "sanity" ); ::breakpoint(); } } while (0); |
| 1366 | // Success - attach condition (new_predicate_bol) to predicate if |
| 1367 | invar.map_ctrl(proj, new_predicate_proj); // so that invariance test can be appropriate |
| 1368 | |
| 1369 | // Eliminate the old If in the loop body |
| 1370 | dominated_by( new_predicate_proj, iff, proj->_con != new_predicate_proj->_con ); |
| 1371 | |
| 1372 | C->set_major_progress(); |
| 1373 | return true; |
| 1374 | } |
| 1375 | |
| 1376 | |
| 1377 | // After pre/main/post loops are created, we'll put a copy of some |
| 1378 | // range checks between the pre and main loop to validate the value |
| 1379 | // of the main loop induction variable. Make a copy of the predicates |
| 1380 | // here with an opaque node as a place holder for the value (will be |
| 1381 | // updated by PhaseIdealLoop::clone_skeleton_predicate()). |
| 1382 | ProjNode* PhaseIdealLoop::insert_initial_skeleton_predicate(IfNode* iff, IdealLoopTree *loop, |
| 1383 | ProjNode* proj, ProjNode *predicate_proj, |
| 1384 | ProjNode* upper_bound_proj, |
| 1385 | int scale, Node* offset, |
| 1386 | Node* init, Node* limit, jint stride, |
| 1387 | Node* rng, bool &overflow, |
| 1388 | Deoptimization::DeoptReason reason) { |
| 1389 | // First predicate for the initial value on first loop iteration |
| 1390 | Node* opaque_init = new OpaqueLoopInitNode(C, init); |
| 1391 | register_new_node(opaque_init, upper_bound_proj); |
| 1392 | bool negate = (proj->_con != predicate_proj->_con); |
| 1393 | BoolNode* bol = rc_predicate(loop, upper_bound_proj, scale, offset, opaque_init, limit, stride, rng, (stride > 0) != (scale > 0), overflow, negate); |
| 1394 | Node* opaque_bol = new Opaque4Node(C, bol, _igvn.intcon(1)); // This will go away once loop opts are over |
| 1395 | C->add_skeleton_predicate_opaq(opaque_bol); |
| 1396 | register_new_node(opaque_bol, upper_bound_proj); |
| 1397 | ProjNode* new_proj = create_new_if_for_predicate(predicate_proj, NULL__null, reason, overflow ? Op_If : iff->Opcode()); |
| 1398 | _igvn.replace_input_of(new_proj->in(0), 1, opaque_bol); |
| 1399 | assert(opaque_init->outcnt() > 0, "should be used")do { if (!(opaque_init->outcnt() > 0)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1399, "assert(" "opaque_init->outcnt() > 0" ") failed" , "should be used"); ::breakpoint(); } } while (0); |
| 1400 | |
| 1401 | // Second predicate for init + (current stride - initial stride) |
| 1402 | // This is identical to the previous predicate initially but as |
| 1403 | // unrolling proceeds current stride is updated. |
| 1404 | Node* init_stride = loop->_head->as_CountedLoop()->stride(); |
| 1405 | Node* opaque_stride = new OpaqueLoopStrideNode(C, init_stride); |
| 1406 | register_new_node(opaque_stride, new_proj); |
| 1407 | Node* max_value = new SubINode(opaque_stride, init_stride); |
| 1408 | register_new_node(max_value, new_proj); |
| 1409 | max_value = new AddINode(opaque_init, max_value); |
| 1410 | register_new_node(max_value, new_proj); |
| 1411 | bol = rc_predicate(loop, new_proj, scale, offset, max_value, limit, stride, rng, (stride > 0) != (scale > 0), overflow, negate); |
| 1412 | opaque_bol = new Opaque4Node(C, bol, _igvn.intcon(1)); |
| 1413 | C->add_skeleton_predicate_opaq(opaque_bol); |
| 1414 | register_new_node(opaque_bol, new_proj); |
| 1415 | new_proj = create_new_if_for_predicate(predicate_proj, NULL__null, reason, overflow ? Op_If : iff->Opcode()); |
| 1416 | _igvn.replace_input_of(new_proj->in(0), 1, opaque_bol); |
| 1417 | assert(max_value->outcnt() > 0, "should be used")do { if (!(max_value->outcnt() > 0)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1417, "assert(" "max_value->outcnt() > 0" ") failed", "should be used"); ::breakpoint(); } } while (0); |
| 1418 | |
| 1419 | return new_proj; |
| 1420 | } |
| 1421 | |
| 1422 | //------------------------------ loop_predication_impl-------------------------- |
| 1423 | // Insert loop predicates for null checks and range checks |
| 1424 | bool PhaseIdealLoop::loop_predication_impl(IdealLoopTree *loop) { |
| 1425 | if (!UseLoopPredicate) return false; |
| 1426 | |
| 1427 | if (!loop->_head->is_Loop()) { |
| 1428 | // Could be a simple region when irreducible loops are present. |
| 1429 | return false; |
| 1430 | } |
| 1431 | LoopNode* head = loop->_head->as_Loop(); |
| 1432 | |
| 1433 | if (head->unique_ctrl_out()->Opcode() == Op_NeverBranch) { |
| 1434 | // do nothing for infinite loops |
| 1435 | return false; |
| 1436 | } |
| 1437 | |
| 1438 | if (head->is_OuterStripMinedLoop()) { |
| 1439 | return false; |
| 1440 | } |
| 1441 | |
| 1442 | CountedLoopNode *cl = NULL__null; |
| 1443 | if (head->is_valid_counted_loop(T_INT)) { |
| 1444 | cl = head->as_CountedLoop(); |
| 1445 | // do nothing for iteration-splitted loops |
| 1446 | if (!cl->is_normal_loop()) return false; |
| 1447 | // Avoid RCE if Counted loop's test is '!='. |
| 1448 | BoolTest::mask bt = cl->loopexit()->test_trip(); |
| 1449 | if (bt != BoolTest::lt && bt != BoolTest::gt) |
| 1450 | cl = NULL__null; |
| 1451 | } |
| 1452 | |
| 1453 | Node* entry = head->skip_strip_mined()->in(LoopNode::EntryControl); |
| 1454 | ProjNode *loop_limit_proj = NULL__null; |
| 1455 | ProjNode *predicate_proj = NULL__null; |
| 1456 | ProjNode *profile_predicate_proj = NULL__null; |
| 1457 | // Loop limit check predicate should be near the loop. |
| 1458 | loop_limit_proj = find_predicate_insertion_point(entry, Deoptimization::Reason_loop_limit_check); |
| 1459 | if (loop_limit_proj != NULL__null) { |
| 1460 | entry = skip_loop_predicates(loop_limit_proj); |
| 1461 | } |
| 1462 | bool has_profile_predicates = false; |
| 1463 | profile_predicate_proj = find_predicate_insertion_point(entry, Deoptimization::Reason_profile_predicate); |
| 1464 | if (profile_predicate_proj != NULL__null) { |
| 1465 | Node* n = skip_loop_predicates(entry); |
| 1466 | // Check if predicates were already added to the profile predicate |
| 1467 | // block |
| 1468 | if (n != entry->in(0)->in(0) || n->outcnt() != 1) { |
| 1469 | has_profile_predicates = true; |
| 1470 | } |
| 1471 | entry = n; |
| 1472 | } |
| 1473 | predicate_proj = find_predicate_insertion_point(entry, Deoptimization::Reason_predicate); |
| 1474 | |
| 1475 | float loop_trip_cnt = -1; |
| 1476 | bool follow_branches = loop_predication_should_follow_branches(loop, profile_predicate_proj, loop_trip_cnt); |
| 1477 | assert(!follow_branches || loop_trip_cnt >= 0, "negative trip count?")do { if (!(!follow_branches || loop_trip_cnt >= 0)) { (*g_assert_poison ) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/opto/loopPredicate.cpp" , 1477, "assert(" "!follow_branches || loop_trip_cnt >= 0" ") failed", "negative trip count?"); ::breakpoint(); } } while (0); |
| 1478 | |
| 1479 | if (predicate_proj == NULL__null && !follow_branches) { |
| 1480 | #ifndef PRODUCT |
| 1481 | if (TraceLoopPredicate) { |
| 1482 | tty->print("missing predicate:"); |
| 1483 | loop->dump_head(); |
| 1484 | head->dump(1); |
| 1485 | } |
| 1486 | #endif |
| 1487 | return false; |
| 1488 | } |
| 1489 | ConNode* zero = _igvn.intcon(0); |
| 1490 | set_ctrl(zero, C->root()); |
| 1491 | |
| 1492 | ResourceArea* area = Thread::current()->resource_area(); |
| 1493 | Invariance invar(area, loop); |
| 1494 | |
| 1495 | // Create list of if-projs such that a newer proj dominates all older |
| 1496 | // projs in the list, and they all dominate loop->tail() |
| 1497 | Node_List if_proj_list; |
| 1498 | Node_List regions; |
| 1499 | Node* current_proj = loop->tail(); // start from tail |
| 1500 | |
| 1501 | |
| 1502 | Node_List controls; |
| 1503 | while (current_proj != head) { |
| 1504 | if (loop == get_loop(current_proj) && // still in the loop ? |
| 1505 | current_proj->is_Proj() && // is a projection ? |
| 1506 | (current_proj->in(0)->Opcode() == Op_If || |
| 1507 | current_proj->in(0)->Opcode() == Op_RangeCheck)) { // is a if projection ? |
| 1508 | if_proj_list.push(current_proj); |
| 1509 | } |
| 1510 | if (follow_branches && |
| 1511 | current_proj->Opcode() == Op_Region && |
| 1512 | loop == get_loop(current_proj)) { |
| 1513 | regions.push(current_proj); |
| 1514 | } |
| 1515 | current_proj = idom(current_proj); |
| 1516 | } |
| 1517 | |
| 1518 | bool hoisted = false; // true if at least one proj is promoted |
| 1519 | |
| 1520 | if (!has_profile_predicates) { |
| 1521 | while (if_proj_list.size() > 0) { |
| 1522 | Node* n = if_proj_list.pop(); |
| 1523 | |
| 1524 | ProjNode* proj = n->as_Proj(); |
| 1525 | IfNode* iff = proj->in(0)->as_If(); |
| 1526 | |
| 1527 | CallStaticJavaNode* call = proj->is_uncommon_trap_if_pattern(Deoptimization::Reason_none); |
| 1528 | if (call == NULL__null) { |
| 1529 | if (loop->is_loop_exit(iff)) { |
| 1530 | // stop processing the remaining projs in the list because the execution of them |
| 1531 | // depends on the condition of "iff" (iff->in(1)). |
| 1532 | break; |
| 1533 | } else { |
| 1534 | // Both arms are inside the loop. There are two cases: |
| 1535 | // (1) there is one backward branch. In this case, any remaining proj |
| 1536 | // in the if_proj list post-dominates "iff". So, the condition of "iff" |
| 1537 | // does not determine the execution the remining projs directly, and we |
| 1538 | // can safely continue. |
| 1539 | // (2) both arms are forwarded, i.e. a diamond shape. In this case, "proj" |
| 1540 | // does not dominate loop->tail(), so it can not be in the if_proj list. |
| 1541 | continue; |
| 1542 | } |
| 1543 | } |
| 1544 | Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(call->uncommon_trap_request()); |
| 1545 | if (reason == Deoptimization::Reason_predicate) { |
| 1546 | break; |
| 1547 | } |
| 1548 | |
| 1549 | if (predicate_proj != NULL__null) { |
| 1550 | hoisted = loop_predication_impl_helper(loop, proj, predicate_proj, cl, zero, invar, Deoptimization::Reason_predicate) | hoisted; |
| 1551 | } |
| 1552 | } // end while |
| 1553 | } |
| 1554 | |
| 1555 | if (follow_branches) { |
| 1556 | PathFrequency pf(loop->_head, this); |
| 1557 | |
| 1558 | // Some projections were skipped by regular predicates because of |
| 1559 | // an early loop exit. Try them with profile data. |
| 1560 | while (if_proj_list.size() > 0) { |
| 1561 | Node* proj = if_proj_list.pop(); |
| 1562 | float f = pf.to(proj); |
| 1563 | if (proj->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none) && |
| 1564 | f * loop_trip_cnt >= 1) { |
| 1565 | hoisted = loop_predication_impl_helper(loop, proj->as_Proj(), profile_predicate_proj, cl, zero, invar, Deoptimization::Reason_profile_predicate) | hoisted; |
| 1566 | } |
| 1567 | } |
| 1568 | |
| 1569 | // And look into all branches |
| 1570 | Node_Stack stack(0); |
| 1571 | VectorSet seen; |
| 1572 | Node_List if_proj_list_freq(area); |
| 1573 | while (regions.size() > 0) { |
| 1574 | Node* c = regions.pop(); |
| 1575 | loop_predication_follow_branches(c, loop, loop_trip_cnt, pf, stack, seen, if_proj_list_freq); |
| 1576 | } |
| 1577 | |
| 1578 | for (uint i = 0; i < if_proj_list_freq.size(); i++) { |
| 1579 | ProjNode* proj = if_proj_list_freq.at(i)->as_Proj(); |
| 1580 | hoisted = loop_predication_impl_helper(loop, proj, profile_predicate_proj, cl, zero, invar, Deoptimization::Reason_profile_predicate) | hoisted; |
| 1581 | } |
| 1582 | } |
| 1583 | |
| 1584 | #ifndef PRODUCT |
| 1585 | // report that the loop predication has been actually performed |
| 1586 | // for this loop |
| 1587 | if (TraceLoopPredicate && hoisted) { |
| 1588 | tty->print("Loop Predication Performed:"); |
| 1589 | loop->dump_head(); |
| 1590 | } |
| 1591 | #endif |
| 1592 | |
| 1593 | head->verify_strip_mined(1); |
| 1594 | |
| 1595 | return hoisted; |
| 1596 | } |
| 1597 | |
| 1598 | //------------------------------loop_predication-------------------------------- |
| 1599 | // driver routine for loop predication optimization |
| 1600 | bool IdealLoopTree::loop_predication( PhaseIdealLoop *phase) { |
| 1601 | bool hoisted = false; |
| 1602 | // Recursively promote predicates |
| 1603 | if (_child) { |
| 1604 | hoisted = _child->loop_predication( phase); |
| 1605 | } |
| 1606 | |
| 1607 | // self |
| 1608 | if (!_irreducible && !tail()->is_top()) { |
| 1609 | hoisted |= phase->loop_predication_impl(this); |
| 1610 | } |
| 1611 | |
| 1612 | if (_next) { //sibling |
| 1613 | hoisted |= _next->loop_predication( phase); |
| 1614 | } |
| 1615 | |
| 1616 | return hoisted; |
| 1617 | } |