Bug Summary

File:jdk/src/hotspot/share/gc/shared/space.cpp
Warning:line 781, column 5
Value stored to 'prev_p' is never read

Annotated Source Code

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name space.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 2 -mthread-model posix -fno-delete-null-pointer-checks -mframe-pointer=all -relaxed-aliasing -fmath-errno -fno-rounding-math -masm-verbose -mconstructor-aliases -munwind-tables -target-cpu x86-64 -dwarf-column-info -fno-split-dwarf-inlining -debugger-tuning=gdb -resource-dir /usr/lib/llvm-10/lib/clang/10.0.0 -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/hotspot/variant-server/libjvm/objs/precompiled -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -D __STDC_CONSTANT_MACROS -D _GNU_SOURCE -D _REENTRANT -D LIBC=gnu -D LINUX -D VM_LITTLE_ENDIAN -D _LP64=1 -D ASSERT -D CHECK_UNHANDLED_OOPS -D TARGET_ARCH_x86 -D INCLUDE_SUFFIX_OS=_linux -D INCLUDE_SUFFIX_CPU=_x86 -D INCLUDE_SUFFIX_COMPILER=_gcc -D TARGET_COMPILER_gcc -D AMD64 -D HOTSPOT_LIB_ARCH="amd64" -D COMPILER1 -D COMPILER2 -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/hotspot/variant-server/gensrc/adfiles -I /home/daniel/Projects/java/jdk/src/hotspot/share -I /home/daniel/Projects/java/jdk/src/hotspot/os/linux -I /home/daniel/Projects/java/jdk/src/hotspot/os/posix -I /home/daniel/Projects/java/jdk/src/hotspot/cpu/x86 -I /home/daniel/Projects/java/jdk/src/hotspot/os_cpu/linux_x86 -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/hotspot/variant-server/gensrc -I /home/daniel/Projects/java/jdk/src/hotspot/share/precompiled -I /home/daniel/Projects/java/jdk/src/hotspot/share/include -I /home/daniel/Projects/java/jdk/src/hotspot/os/posix/include -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/support/modules_include/java.base -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/support/modules_include/java.base/linux -I /home/daniel/Projects/java/jdk/src/java.base/share/native/libjimage -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/hotspot/variant-server/gensrc/adfiles -I /home/daniel/Projects/java/jdk/src/hotspot/share -I /home/daniel/Projects/java/jdk/src/hotspot/os/linux -I /home/daniel/Projects/java/jdk/src/hotspot/os/posix -I /home/daniel/Projects/java/jdk/src/hotspot/cpu/x86 -I /home/daniel/Projects/java/jdk/src/hotspot/os_cpu/linux_x86 -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/hotspot/variant-server/gensrc -D _FORTIFY_SOURCE=2 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.5.0/../../../../include/c++/7.5.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.5.0/../../../../include/x86_64-linux-gnu/c++/7.5.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.5.0/../../../../include/x86_64-linux-gnu/c++/7.5.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.5.0/../../../../include/c++/7.5.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-10/lib/clang/10.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O3 -Wno-format-zero-length -Wno-unused-parameter -Wno-unused -Wno-parentheses -Wno-comment -Wno-unknown-pragmas -Wno-address -Wno-delete-non-virtual-dtor -Wno-char-subscripts -Wno-array-bounds -Wno-int-in-bool-context -Wno-ignored-qualifiers -Wno-missing-field-initializers -Wno-implicit-fallthrough -Wno-empty-body -Wno-strict-overflow -Wno-sequence-point -Wno-maybe-uninitialized -Wno-misleading-indentation -Wno-cast-function-type -Wno-shift-negative-value -std=c++14 -fdeprecated-macro -fdebug-compilation-dir /home/daniel/Projects/java/jdk/make/hotspot -ferror-limit 19 -fmessage-length 0 -fvisibility hidden -stack-protector 1 -fno-rtti -fgnuc-version=4.2.1 -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -faddrsig -o /home/daniel/Projects/java/scan/2021-12-21-193737-8510-1 -x c++ /home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp
1/*
2 * Copyright (c) 1997, 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 "classfile/vmClasses.hpp"
27#include "classfile/vmSymbols.hpp"
28#include "gc/shared/blockOffsetTable.inline.hpp"
29#include "gc/shared/collectedHeap.inline.hpp"
30#include "gc/shared/genCollectedHeap.hpp"
31#include "gc/shared/genOopClosures.inline.hpp"
32#include "gc/shared/space.hpp"
33#include "gc/shared/space.inline.hpp"
34#include "gc/shared/spaceDecorator.inline.hpp"
35#include "memory/iterator.inline.hpp"
36#include "memory/universe.hpp"
37#include "oops/oop.inline.hpp"
38#include "runtime/atomic.hpp"
39#include "runtime/java.hpp"
40#include "runtime/prefetch.inline.hpp"
41#include "runtime/safepoint.hpp"
42#include "utilities/align.hpp"
43#include "utilities/copy.hpp"
44#include "utilities/globalDefinitions.hpp"
45#include "utilities/macros.hpp"
46#if INCLUDE_SERIALGC1
47#include "gc/serial/defNewGeneration.hpp"
48#endif
49
50HeapWord* DirtyCardToOopClosure::get_actual_top(HeapWord* top,
51 HeapWord* top_obj) {
52 if (top_obj != NULL__null) {
53 if (_sp->block_is_obj(top_obj)) {
54 if (_precision == CardTable::ObjHeadPreciseArray) {
55 if (cast_to_oop(top_obj)->is_objArray() || cast_to_oop(top_obj)->is_typeArray()) {
56 // An arrayOop is starting on the dirty card - since we do exact
57 // store checks for objArrays we are done.
58 } else {
59 // Otherwise, it is possible that the object starting on the dirty
60 // card spans the entire card, and that the store happened on a
61 // later card. Figure out where the object ends.
62 // Use the block_size() method of the space over which
63 // the iteration is being done. That space (e.g. CMS) may have
64 // specific requirements on object sizes which will
65 // be reflected in the block_size() method.
66 top = top_obj + cast_to_oop(top_obj)->size();
67 }
68 }
69 } else {
70 top = top_obj;
71 }
72 } else {
73 assert(top == _sp->end(), "only case where top_obj == NULL")do { if (!(top == _sp->end())) { (*g_assert_poison) = 'X';
; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 73, "assert(" "top == _sp->end()" ") failed", "only case where top_obj == NULL"
); ::breakpoint(); } } while (0);
74 }
75 return top;
76}
77
78void DirtyCardToOopClosure::walk_mem_region(MemRegion mr,
79 HeapWord* bottom,
80 HeapWord* top) {
81 // 1. Blocks may or may not be objects.
82 // 2. Even when a block_is_obj(), it may not entirely
83 // occupy the block if the block quantum is larger than
84 // the object size.
85 // We can and should try to optimize by calling the non-MemRegion
86 // version of oop_iterate() for all but the extremal objects
87 // (for which we need to call the MemRegion version of
88 // oop_iterate()) To be done post-beta XXX
89 for (; bottom < top; bottom += _sp->block_size(bottom)) {
90 // As in the case of contiguous space above, we'd like to
91 // just use the value returned by oop_iterate to increment the
92 // current pointer; unfortunately, that won't work in CMS because
93 // we'd need an interface change (it seems) to have the space
94 // "adjust the object size" (for instance pad it up to its
95 // block alignment or minimum block size restrictions. XXX
96 if (_sp->block_is_obj(bottom) &&
97 !_sp->obj_allocated_since_save_marks(cast_to_oop(bottom))) {
98 cast_to_oop(bottom)->oop_iterate(_cl, mr);
99 }
100 }
101}
102
103// We get called with "mr" representing the dirty region
104// that we want to process. Because of imprecise marking,
105// we may need to extend the incoming "mr" to the right,
106// and scan more. However, because we may already have
107// scanned some of that extended region, we may need to
108// trim its right-end back some so we do not scan what
109// we (or another worker thread) may already have scanned
110// or planning to scan.
111void DirtyCardToOopClosure::do_MemRegion(MemRegion mr) {
112 HeapWord* bottom = mr.start();
113 HeapWord* last = mr.last();
114 HeapWord* top = mr.end();
115 HeapWord* bottom_obj;
116 HeapWord* top_obj;
117
118 assert(_precision == CardTable::ObjHeadPreciseArray ||do { if (!(_precision == CardTable::ObjHeadPreciseArray || _precision
== CardTable::Precise)) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 120, "assert(" "_precision == CardTable::ObjHeadPreciseArray || _precision == CardTable::Precise"
") failed", "Only ones we deal with for now."); ::breakpoint
(); } } while (0)
119 _precision == CardTable::Precise,do { if (!(_precision == CardTable::ObjHeadPreciseArray || _precision
== CardTable::Precise)) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 120, "assert(" "_precision == CardTable::ObjHeadPreciseArray || _precision == CardTable::Precise"
") failed", "Only ones we deal with for now."); ::breakpoint
(); } } while (0)
120 "Only ones we deal with for now.")do { if (!(_precision == CardTable::ObjHeadPreciseArray || _precision
== CardTable::Precise)) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 120, "assert(" "_precision == CardTable::ObjHeadPreciseArray || _precision == CardTable::Precise"
") failed", "Only ones we deal with for now."); ::breakpoint
(); } } while (0);
121
122 assert(_precision != CardTable::ObjHeadPreciseArray ||do { if (!(_precision != CardTable::ObjHeadPreciseArray || _last_bottom
== __null || top <= _last_bottom)) { (*g_assert_poison) =
'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 124, "assert(" "_precision != CardTable::ObjHeadPreciseArray || _last_bottom == __null || top <= _last_bottom"
") failed", "Not decreasing"); ::breakpoint(); } } while (0)
123 _last_bottom == NULL || top <= _last_bottom,do { if (!(_precision != CardTable::ObjHeadPreciseArray || _last_bottom
== __null || top <= _last_bottom)) { (*g_assert_poison) =
'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 124, "assert(" "_precision != CardTable::ObjHeadPreciseArray || _last_bottom == __null || top <= _last_bottom"
") failed", "Not decreasing"); ::breakpoint(); } } while (0)
124 "Not decreasing")do { if (!(_precision != CardTable::ObjHeadPreciseArray || _last_bottom
== __null || top <= _last_bottom)) { (*g_assert_poison) =
'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 124, "assert(" "_precision != CardTable::ObjHeadPreciseArray || _last_bottom == __null || top <= _last_bottom"
") failed", "Not decreasing"); ::breakpoint(); } } while (0);
125 NOT_PRODUCT(_last_bottom = mr.start())_last_bottom = mr.start();
126
127 bottom_obj = _sp->block_start(bottom);
128 top_obj = _sp->block_start(last);
129
130 assert(bottom_obj <= bottom, "just checking")do { if (!(bottom_obj <= bottom)) { (*g_assert_poison) = 'X'
;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 130, "assert(" "bottom_obj <= bottom" ") failed", "just checking"
); ::breakpoint(); } } while (0);
131 assert(top_obj <= top, "just checking")do { if (!(top_obj <= top)) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 131, "assert(" "top_obj <= top" ") failed", "just checking"
); ::breakpoint(); } } while (0);
132
133 // Given what we think is the top of the memory region and
134 // the start of the object at the top, get the actual
135 // value of the top.
136 top = get_actual_top(top, top_obj);
137
138 // If the previous call did some part of this region, don't redo.
139 if (_precision == CardTable::ObjHeadPreciseArray &&
140 _min_done != NULL__null &&
141 _min_done < top) {
142 top = _min_done;
143 }
144
145 // Top may have been reset, and in fact may be below bottom,
146 // e.g. the dirty card region is entirely in a now free object
147 // -- something that could happen with a concurrent sweeper.
148 bottom = MIN2(bottom, top);
149 MemRegion extended_mr = MemRegion(bottom, top);
150 assert(bottom <= top &&do { if (!(bottom <= top && (_precision != CardTable
::ObjHeadPreciseArray || _min_done == __null || top <= _min_done
))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 154, "assert(" "bottom <= top && (_precision != CardTable::ObjHeadPreciseArray || _min_done == __null || top <= _min_done)"
") failed", "overlap!"); ::breakpoint(); } } while (0)
151 (_precision != CardTable::ObjHeadPreciseArray ||do { if (!(bottom <= top && (_precision != CardTable
::ObjHeadPreciseArray || _min_done == __null || top <= _min_done
))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 154, "assert(" "bottom <= top && (_precision != CardTable::ObjHeadPreciseArray || _min_done == __null || top <= _min_done)"
") failed", "overlap!"); ::breakpoint(); } } while (0)
152 _min_done == NULL ||do { if (!(bottom <= top && (_precision != CardTable
::ObjHeadPreciseArray || _min_done == __null || top <= _min_done
))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 154, "assert(" "bottom <= top && (_precision != CardTable::ObjHeadPreciseArray || _min_done == __null || top <= _min_done)"
") failed", "overlap!"); ::breakpoint(); } } while (0)
153 top <= _min_done),do { if (!(bottom <= top && (_precision != CardTable
::ObjHeadPreciseArray || _min_done == __null || top <= _min_done
))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 154, "assert(" "bottom <= top && (_precision != CardTable::ObjHeadPreciseArray || _min_done == __null || top <= _min_done)"
") failed", "overlap!"); ::breakpoint(); } } while (0)
154 "overlap!")do { if (!(bottom <= top && (_precision != CardTable
::ObjHeadPreciseArray || _min_done == __null || top <= _min_done
))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 154, "assert(" "bottom <= top && (_precision != CardTable::ObjHeadPreciseArray || _min_done == __null || top <= _min_done)"
") failed", "overlap!"); ::breakpoint(); } } while (0);
155
156 // Walk the region if it is not empty; otherwise there is nothing to do.
157 if (!extended_mr.is_empty()) {
158 walk_mem_region(extended_mr, bottom_obj, top);
159 }
160
161 _min_done = bottom;
162}
163
164DirtyCardToOopClosure* Space::new_dcto_cl(OopIterateClosure* cl,
165 CardTable::PrecisionStyle precision,
166 HeapWord* boundary) {
167 return new DirtyCardToOopClosure(this, cl, precision, boundary);
168}
169
170HeapWord* ContiguousSpaceDCTOC::get_actual_top(HeapWord* top,
171 HeapWord* top_obj) {
172 if (top_obj != NULL__null && top_obj < (_sp->toContiguousSpace())->top()) {
173 if (_precision == CardTable::ObjHeadPreciseArray) {
174 if (cast_to_oop(top_obj)->is_objArray() || cast_to_oop(top_obj)->is_typeArray()) {
175 // An arrayOop is starting on the dirty card - since we do exact
176 // store checks for objArrays we are done.
177 } else {
178 // Otherwise, it is possible that the object starting on the dirty
179 // card spans the entire card, and that the store happened on a
180 // later card. Figure out where the object ends.
181 assert(_sp->block_size(top_obj) == cast_to_oop(top_obj)->size(),do { if (!(_sp->block_size(top_obj) == cast_to_oop(top_obj
)->size())) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 182, "assert(" "_sp->block_size(top_obj) == cast_to_oop(top_obj)->size()"
") failed", "Block size and object size mismatch"); ::breakpoint
(); } } while (0)
182 "Block size and object size mismatch")do { if (!(_sp->block_size(top_obj) == cast_to_oop(top_obj
)->size())) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 182, "assert(" "_sp->block_size(top_obj) == cast_to_oop(top_obj)->size()"
") failed", "Block size and object size mismatch"); ::breakpoint
(); } } while (0);
183 top = top_obj + cast_to_oop(top_obj)->size();
184 }
185 }
186 } else {
187 top = (_sp->toContiguousSpace())->top();
188 }
189 return top;
190}
191
192void FilteringDCTOC::walk_mem_region(MemRegion mr,
193 HeapWord* bottom,
194 HeapWord* top) {
195 // Note that this assumption won't hold if we have a concurrent
196 // collector in this space, which may have freed up objects after
197 // they were dirtied and before the stop-the-world GC that is
198 // examining cards here.
199 assert(bottom < top, "ought to be at least one obj on a dirty card.")do { if (!(bottom < top)) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 199, "assert(" "bottom < top" ") failed", "ought to be at least one obj on a dirty card."
); ::breakpoint(); } } while (0);
200
201 if (_boundary != NULL__null) {
202 // We have a boundary outside of which we don't want to look
203 // at objects, so create a filtering closure around the
204 // oop closure before walking the region.
205 FilteringClosure filter(_boundary, _cl);
206 walk_mem_region_with_cl(mr, bottom, top, &filter);
207 } else {
208 // No boundary, simply walk the heap with the oop closure.
209 walk_mem_region_with_cl(mr, bottom, top, _cl);
210 }
211
212}
213
214// We must replicate this so that the static type of "FilteringClosure"
215// (see above) is apparent at the oop_iterate calls.
216#define ContiguousSpaceDCTOC__walk_mem_region_with_cl_DEFN(ClosureType)void ContiguousSpaceDCTOC::walk_mem_region_with_cl(MemRegion mr
, HeapWord* bottom, HeapWord* top, ClosureType* cl) { bottom +=
cast_to_oop(bottom)->oop_iterate_size(cl, mr); if (bottom
< top) { HeapWord* next_obj = bottom + cast_to_oop(bottom
)->size(); while (next_obj < top) { cast_to_oop(bottom)
->oop_iterate(cl); bottom = next_obj; next_obj = bottom + cast_to_oop
(bottom)->size(); } cast_to_oop(bottom)->oop_iterate(cl
, mr); } } \
217void ContiguousSpaceDCTOC::walk_mem_region_with_cl(MemRegion mr, \
218 HeapWord* bottom, \
219 HeapWord* top, \
220 ClosureType* cl) { \
221 bottom += cast_to_oop(bottom)->oop_iterate_size(cl, mr); \
222 if (bottom < top) { \
223 HeapWord* next_obj = bottom + cast_to_oop(bottom)->size(); \
224 while (next_obj < top) { \
225 /* Bottom lies entirely below top, so we can call the */ \
226 /* non-memRegion version of oop_iterate below. */ \
227 cast_to_oop(bottom)->oop_iterate(cl); \
228 bottom = next_obj; \
229 next_obj = bottom + cast_to_oop(bottom)->size(); \
230 } \
231 /* Last object. */ \
232 cast_to_oop(bottom)->oop_iterate(cl, mr); \
233 } \
234}
235
236// (There are only two of these, rather than N, because the split is due
237// only to the introduction of the FilteringClosure, a local part of the
238// impl of this abstraction.)
239ContiguousSpaceDCTOC__walk_mem_region_with_cl_DEFN(OopIterateClosure)void ContiguousSpaceDCTOC::walk_mem_region_with_cl(MemRegion mr
, HeapWord* bottom, HeapWord* top, OopIterateClosure* cl) { bottom
+= cast_to_oop(bottom)->oop_iterate_size(cl, mr); if (bottom
< top) { HeapWord* next_obj = bottom + cast_to_oop(bottom
)->size(); while (next_obj < top) { cast_to_oop(bottom)
->oop_iterate(cl); bottom = next_obj; next_obj = bottom + cast_to_oop
(bottom)->size(); } cast_to_oop(bottom)->oop_iterate(cl
, mr); } }
240ContiguousSpaceDCTOC__walk_mem_region_with_cl_DEFN(FilteringClosure)void ContiguousSpaceDCTOC::walk_mem_region_with_cl(MemRegion mr
, HeapWord* bottom, HeapWord* top, FilteringClosure* cl) { bottom
+= cast_to_oop(bottom)->oop_iterate_size(cl, mr); if (bottom
< top) { HeapWord* next_obj = bottom + cast_to_oop(bottom
)->size(); while (next_obj < top) { cast_to_oop(bottom)
->oop_iterate(cl); bottom = next_obj; next_obj = bottom + cast_to_oop
(bottom)->size(); } cast_to_oop(bottom)->oop_iterate(cl
, mr); } }
241
242DirtyCardToOopClosure*
243ContiguousSpace::new_dcto_cl(OopIterateClosure* cl,
244 CardTable::PrecisionStyle precision,
245 HeapWord* boundary) {
246 return new ContiguousSpaceDCTOC(this, cl, precision, boundary);
247}
248
249void Space::initialize(MemRegion mr,
250 bool clear_space,
251 bool mangle_space) {
252 HeapWord* bottom = mr.start();
253 HeapWord* end = mr.end();
254 assert(Universe::on_page_boundary(bottom) && Universe::on_page_boundary(end),do { if (!(Universe::on_page_boundary(bottom) && Universe
::on_page_boundary(end))) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 255, "assert(" "Universe::on_page_boundary(bottom) && Universe::on_page_boundary(end)"
") failed", "invalid space boundaries"); ::breakpoint(); } }
while (0)
255 "invalid space boundaries")do { if (!(Universe::on_page_boundary(bottom) && Universe
::on_page_boundary(end))) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 255, "assert(" "Universe::on_page_boundary(bottom) && Universe::on_page_boundary(end)"
") failed", "invalid space boundaries"); ::breakpoint(); } }
while (0);
256 set_bottom(bottom);
257 set_end(end);
258 if (clear_space) clear(mangle_space);
259}
260
261void Space::clear(bool mangle_space) {
262 if (ZapUnusedHeapArea && mangle_space) {
263 mangle_unused_area();
264 }
265}
266
267ContiguousSpace::ContiguousSpace(): CompactibleSpace(), _top(NULL__null) {
268 _mangler = new GenSpaceMangler(this);
269}
270
271ContiguousSpace::~ContiguousSpace() {
272 delete _mangler;
273}
274
275void ContiguousSpace::initialize(MemRegion mr,
276 bool clear_space,
277 bool mangle_space)
278{
279 CompactibleSpace::initialize(mr, clear_space, mangle_space);
280}
281
282void ContiguousSpace::clear(bool mangle_space) {
283 set_top(bottom());
284 set_saved_mark();
285 CompactibleSpace::clear(mangle_space);
286}
287
288bool ContiguousSpace::is_free_block(const HeapWord* p) const {
289 return p >= _top;
290}
291
292void OffsetTableContigSpace::clear(bool mangle_space) {
293 ContiguousSpace::clear(mangle_space);
294 _offsets.initialize_threshold();
295}
296
297void OffsetTableContigSpace::set_bottom(HeapWord* new_bottom) {
298 Space::set_bottom(new_bottom);
299 _offsets.set_bottom(new_bottom);
300}
301
302void OffsetTableContigSpace::set_end(HeapWord* new_end) {
303 // Space should not advertise an increase in size
304 // until after the underlying offset table has been enlarged.
305 _offsets.resize(pointer_delta(new_end, bottom()));
306 Space::set_end(new_end);
307}
308
309#ifndef PRODUCT
310
311void ContiguousSpace::set_top_for_allocations(HeapWord* v) {
312 mangler()->set_top_for_allocations(v);
313}
314void ContiguousSpace::set_top_for_allocations() {
315 mangler()->set_top_for_allocations(top());
316}
317void ContiguousSpace::check_mangled_unused_area(HeapWord* limit) {
318 mangler()->check_mangled_unused_area(limit);
319}
320
321void ContiguousSpace::check_mangled_unused_area_complete() {
322 mangler()->check_mangled_unused_area_complete();
323}
324
325// Mangled only the unused space that has not previously
326// been mangled and that has not been allocated since being
327// mangled.
328void ContiguousSpace::mangle_unused_area() {
329 mangler()->mangle_unused_area();
330}
331void ContiguousSpace::mangle_unused_area_complete() {
332 mangler()->mangle_unused_area_complete();
333}
334#endif // NOT_PRODUCT
335
336void CompactibleSpace::initialize(MemRegion mr,
337 bool clear_space,
338 bool mangle_space) {
339 Space::initialize(mr, clear_space, mangle_space);
340 set_compaction_top(bottom());
341 _next_compaction_space = NULL__null;
342}
343
344void CompactibleSpace::clear(bool mangle_space) {
345 Space::clear(mangle_space);
346 _compaction_top = bottom();
347}
348
349HeapWord* CompactibleSpace::forward(oop q, size_t size,
350 CompactPoint* cp, HeapWord* compact_top) {
351 // q is alive
352 // First check if we should switch compaction space
353 assert(this == cp->space, "'this' should be current compaction space.")do { if (!(this == cp->space)) { (*g_assert_poison) = 'X';
; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 353, "assert(" "this == cp->space" ") failed", "'this' should be current compaction space."
); ::breakpoint(); } } while (0);
354 size_t compaction_max_size = pointer_delta(end(), compact_top);
355 while (size > compaction_max_size) {
356 // switch to next compaction space
357 cp->space->set_compaction_top(compact_top);
358 cp->space = cp->space->next_compaction_space();
359 if (cp->space == NULL__null) {
360 cp->gen = GenCollectedHeap::heap()->young_gen();
361 assert(cp->gen != NULL, "compaction must succeed")do { if (!(cp->gen != __null)) { (*g_assert_poison) = 'X';
; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 361, "assert(" "cp->gen != __null" ") failed", "compaction must succeed"
); ::breakpoint(); } } while (0);
362 cp->space = cp->gen->first_compaction_space();
363 assert(cp->space != NULL, "generation must have a first compaction space")do { if (!(cp->space != __null)) { (*g_assert_poison) = 'X'
;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 363, "assert(" "cp->space != __null" ") failed", "generation must have a first compaction space"
); ::breakpoint(); } } while (0);
364 }
365 compact_top = cp->space->bottom();
366 cp->space->set_compaction_top(compact_top);
367 cp->space->initialize_threshold();
368 compaction_max_size = pointer_delta(cp->space->end(), compact_top);
369 }
370
371 // store the forwarding pointer into the mark word
372 if (cast_from_oop<HeapWord*>(q) != compact_top) {
373 q->forward_to(cast_to_oop(compact_top));
374 assert(q->is_gc_marked(), "encoding the pointer should preserve the mark")do { if (!(q->is_gc_marked())) { (*g_assert_poison) = 'X';
; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 374, "assert(" "q->is_gc_marked()" ") failed", "encoding the pointer should preserve the mark"
); ::breakpoint(); } } while (0);
375 } else {
376 // if the object isn't moving we can just set the mark to the default
377 // mark and handle it specially later on.
378 q->init_mark();
379 assert(!q->is_forwarded(), "should not be forwarded")do { if (!(!q->is_forwarded())) { (*g_assert_poison) = 'X'
;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 379, "assert(" "!q->is_forwarded()" ") failed", "should not be forwarded"
); ::breakpoint(); } } while (0);
380 }
381
382 compact_top += size;
383
384 // We need to update the offset table so that the beginnings of objects can be
385 // found during scavenge. Note that we are updating the offset table based on
386 // where the object will be once the compaction phase finishes.
387 cp->space->alloc_block(compact_top - size, compact_top);
388 return compact_top;
389}
390
391#if INCLUDE_SERIALGC1
392
393void ContiguousSpace::prepare_for_compaction(CompactPoint* cp) {
394 // Compute the new addresses for the live objects and store it in the mark
395 // Used by universe::mark_sweep_phase2()
396
397 // We're sure to be here before any objects are compacted into this
398 // space, so this is a good time to initialize this:
399 set_compaction_top(bottom());
400
401 if (cp->space == NULL__null) {
402 assert(cp->gen != NULL, "need a generation")do { if (!(cp->gen != __null)) { (*g_assert_poison) = 'X';
; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 402, "assert(" "cp->gen != __null" ") failed", "need a generation"
); ::breakpoint(); } } while (0);
403 assert(cp->gen->first_compaction_space() == this, "just checking")do { if (!(cp->gen->first_compaction_space() == this)) {
(*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 403, "assert(" "cp->gen->first_compaction_space() == this"
") failed", "just checking"); ::breakpoint(); } } while (0);
404 cp->space = cp->gen->first_compaction_space();
405 cp->space->initialize_threshold();
406 cp->space->set_compaction_top(cp->space->bottom());
407 }
408
409 HeapWord* compact_top = cp->space->compaction_top(); // This is where we are currently compacting to.
410
411 DeadSpacer dead_spacer(this);
412
413 HeapWord* end_of_live = bottom(); // One byte beyond the last byte of the last live object.
414 HeapWord* first_dead = NULL__null; // The first dead object.
415
416 const intx interval = PrefetchScanIntervalInBytes;
417
418 HeapWord* cur_obj = bottom();
419 HeapWord* scan_limit = top();
420
421 while (cur_obj < scan_limit) {
422 if (cast_to_oop(cur_obj)->is_gc_marked()) {
423 // prefetch beyond cur_obj
424 Prefetch::write(cur_obj, interval);
425 size_t size = cast_to_oop(cur_obj)->size();
426 compact_top = cp->space->forward(cast_to_oop(cur_obj), size, cp, compact_top);
427 cur_obj += size;
428 end_of_live = cur_obj;
429 } else {
430 // run over all the contiguous dead objects
431 HeapWord* end = cur_obj;
432 do {
433 // prefetch beyond end
434 Prefetch::write(end, interval);
435 end += cast_to_oop(end)->size();
436 } while (end < scan_limit && !cast_to_oop(end)->is_gc_marked());
437
438 // see if we might want to pretend this object is alive so that
439 // we don't have to compact quite as often.
440 if (cur_obj == compact_top && dead_spacer.insert_deadspace(cur_obj, end)) {
441 oop obj = cast_to_oop(cur_obj);
442 compact_top = cp->space->forward(obj, obj->size(), cp, compact_top);
443 end_of_live = end;
444 } else {
445 // otherwise, it really is a free region.
446
447 // cur_obj is a pointer to a dead object. Use this dead memory to store a pointer to the next live object.
448 *(HeapWord**)cur_obj = end;
449
450 // see if this is the first dead region.
451 if (first_dead == NULL__null) {
452 first_dead = cur_obj;
453 }
454 }
455
456 // move on to the next object
457 cur_obj = end;
458 }
459 }
460
461 assert(cur_obj == scan_limit, "just checking")do { if (!(cur_obj == scan_limit)) { (*g_assert_poison) = 'X'
;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 461, "assert(" "cur_obj == scan_limit" ") failed", "just checking"
); ::breakpoint(); } } while (0);
462 _end_of_live = end_of_live;
463 if (first_dead != NULL__null) {
464 _first_dead = first_dead;
465 } else {
466 _first_dead = end_of_live;
467 }
468
469 // save the compaction_top of the compaction space.
470 cp->space->set_compaction_top(compact_top);
471}
472
473void CompactibleSpace::adjust_pointers() {
474 // Check first is there is any work to do.
475 if (used() == 0) {
476 return; // Nothing to do.
477 }
478
479 // adjust all the interior pointers to point at the new locations of objects
480 // Used by MarkSweep::mark_sweep_phase3()
481
482 HeapWord* cur_obj = bottom();
483 HeapWord* const end_of_live = _end_of_live; // Established by prepare_for_compaction().
484 HeapWord* const first_dead = _first_dead; // Established by prepare_for_compaction().
485
486 assert(first_dead <= end_of_live, "Stands to reason, no?")do { if (!(first_dead <= end_of_live)) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 486, "assert(" "first_dead <= end_of_live" ") failed", "Stands to reason, no?"
); ::breakpoint(); } } while (0);
487
488 const intx interval = PrefetchScanIntervalInBytes;
489
490 debug_only(HeapWord* prev_obj = NULL)HeapWord* prev_obj = __null;
491 while (cur_obj < end_of_live) {
492 Prefetch::write(cur_obj, interval);
493 if (cur_obj < first_dead || cast_to_oop(cur_obj)->is_gc_marked()) {
494 // cur_obj is alive
495 // point all the oops to the new location
496 size_t size = MarkSweep::adjust_pointers(cast_to_oop(cur_obj));
497 debug_only(prev_obj = cur_obj)prev_obj = cur_obj;
498 cur_obj += size;
499 } else {
500 debug_only(prev_obj = cur_obj)prev_obj = cur_obj;
501 // cur_obj is not a live object, instead it points at the next live object
502 cur_obj = *(HeapWord**)cur_obj;
503 assert(cur_obj > prev_obj, "we should be moving forward through memory, cur_obj: " PTR_FORMAT ", prev_obj: " PTR_FORMAT, p2i(cur_obj), p2i(prev_obj))do { if (!(cur_obj > prev_obj)) { (*g_assert_poison) = 'X'
;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 503, "assert(" "cur_obj > prev_obj" ") failed", "we should be moving forward through memory, cur_obj: "
"0x%016" "l" "x" ", prev_obj: " "0x%016" "l" "x", p2i(cur_obj
), p2i(prev_obj)); ::breakpoint(); } } while (0);
504 }
505 }
506
507 assert(cur_obj == end_of_live, "just checking")do { if (!(cur_obj == end_of_live)) { (*g_assert_poison) = 'X'
;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 507, "assert(" "cur_obj == end_of_live" ") failed", "just checking"
); ::breakpoint(); } } while (0);
508}
509
510void CompactibleSpace::compact() {
511 // Copy all live objects to their new location
512 // Used by MarkSweep::mark_sweep_phase4()
513
514 verify_up_to_first_dead(this);
515
516 HeapWord* const start = bottom();
517 HeapWord* const end_of_live = _end_of_live;
518
519 assert(_first_dead <= end_of_live, "Invariant. _first_dead: " PTR_FORMAT " <= end_of_live: " PTR_FORMAT, p2i(_first_dead), p2i(end_of_live))do { if (!(_first_dead <= end_of_live)) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 519, "assert(" "_first_dead <= end_of_live" ") failed", "Invariant. _first_dead: "
"0x%016" "l" "x" " <= end_of_live: " "0x%016" "l" "x", p2i
(_first_dead), p2i(end_of_live)); ::breakpoint(); } } while (
0);
520 if (_first_dead == end_of_live && (start == end_of_live || !cast_to_oop(start)->is_gc_marked())) {
521 // Nothing to compact. The space is either empty or all live object should be left in place.
522 clear_empty_region(this);
523 return;
524 }
525
526 const intx scan_interval = PrefetchScanIntervalInBytes;
527 const intx copy_interval = PrefetchCopyIntervalInBytes;
528
529 assert(start < end_of_live, "bottom: " PTR_FORMAT " should be < end_of_live: " PTR_FORMAT, p2i(start), p2i(end_of_live))do { if (!(start < end_of_live)) { (*g_assert_poison) = 'X'
;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 529, "assert(" "start < end_of_live" ") failed", "bottom: "
"0x%016" "l" "x" " should be < end_of_live: " "0x%016" "l"
"x", p2i(start), p2i(end_of_live)); ::breakpoint(); } } while
(0);
530 HeapWord* cur_obj = start;
531 if (_first_dead > cur_obj && !cast_to_oop(cur_obj)->is_gc_marked()) {
532 // All object before _first_dead can be skipped. They should not be moved.
533 // A pointer to the first live object is stored at the memory location for _first_dead.
534 cur_obj = *(HeapWord**)(_first_dead);
535 }
536
537 debug_only(HeapWord* prev_obj = NULL)HeapWord* prev_obj = __null;
538 while (cur_obj < end_of_live) {
539 if (!cast_to_oop(cur_obj)->is_forwarded()) {
540 debug_only(prev_obj = cur_obj)prev_obj = cur_obj;
541 // The first word of the dead object contains a pointer to the next live object or end of space.
542 cur_obj = *(HeapWord**)cur_obj;
543 assert(cur_obj > prev_obj, "we should be moving forward through memory")do { if (!(cur_obj > prev_obj)) { (*g_assert_poison) = 'X'
;; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 543, "assert(" "cur_obj > prev_obj" ") failed", "we should be moving forward through memory"
); ::breakpoint(); } } while (0);
544 } else {
545 // prefetch beyond q
546 Prefetch::read(cur_obj, scan_interval);
547
548 // size and destination
549 size_t size = cast_to_oop(cur_obj)->size();
550 HeapWord* compaction_top = cast_from_oop<HeapWord*>(cast_to_oop(cur_obj)->forwardee());
551
552 // prefetch beyond compaction_top
553 Prefetch::write(compaction_top, copy_interval);
554
555 // copy object and reinit its mark
556 assert(cur_obj != compaction_top, "everything in this pass should be moving")do { if (!(cur_obj != compaction_top)) { (*g_assert_poison) =
'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 556, "assert(" "cur_obj != compaction_top" ") failed", "everything in this pass should be moving"
); ::breakpoint(); } } while (0);
557 Copy::aligned_conjoint_words(cur_obj, compaction_top, size);
558 cast_to_oop(compaction_top)->init_mark();
559 assert(cast_to_oop(compaction_top)->klass() != NULL, "should have a class")do { if (!(cast_to_oop(compaction_top)->klass() != __null)
) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 559, "assert(" "cast_to_oop(compaction_top)->klass() != __null"
") failed", "should have a class"); ::breakpoint(); } } while
(0);
560
561 debug_only(prev_obj = cur_obj)prev_obj = cur_obj;
562 cur_obj += size;
563 }
564 }
565
566 clear_empty_region(this);
567}
568
569#endif // INCLUDE_SERIALGC
570
571void Space::print_short() const { print_short_on(tty); }
572
573void Space::print_short_on(outputStream* st) const {
574 st->print(" space " SIZE_FORMAT"%" "l" "u" "K, %3d%% used", capacity() / K,
575 (int) ((double) used() * 100 / capacity()));
576}
577
578void Space::print() const { print_on(tty); }
579
580void Space::print_on(outputStream* st) const {
581 print_short_on(st);
582 st->print_cr(" [" INTPTR_FORMAT"0x%016" "l" "x" ", " INTPTR_FORMAT"0x%016" "l" "x" ")",
583 p2i(bottom()), p2i(end()));
584}
585
586void ContiguousSpace::print_on(outputStream* st) const {
587 print_short_on(st);
588 st->print_cr(" [" INTPTR_FORMAT"0x%016" "l" "x" ", " INTPTR_FORMAT"0x%016" "l" "x" ", " INTPTR_FORMAT"0x%016" "l" "x" ")",
589 p2i(bottom()), p2i(top()), p2i(end()));
590}
591
592void OffsetTableContigSpace::print_on(outputStream* st) const {
593 print_short_on(st);
594 st->print_cr(" [" INTPTR_FORMAT"0x%016" "l" "x" ", " INTPTR_FORMAT"0x%016" "l" "x" ", "
595 INTPTR_FORMAT"0x%016" "l" "x" ", " INTPTR_FORMAT"0x%016" "l" "x" ")",
596 p2i(bottom()), p2i(top()), p2i(_offsets.threshold()), p2i(end()));
597}
598
599void ContiguousSpace::verify() const {
600 HeapWord* p = bottom();
601 HeapWord* t = top();
602 HeapWord* prev_p = NULL__null;
603 while (p < t) {
604 oopDesc::verify(cast_to_oop(p));
605 prev_p = p;
606 p += cast_to_oop(p)->size();
607 }
608 guarantee(p == top(), "end of last object must match end of space")do { if (!(p == top())) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 608, "guarantee(" "p == top()" ") failed", "end of last object must match end of space"
); ::breakpoint(); } } while (0);
609 if (top() != end()) {
610 guarantee(top() == block_start_const(end()-1) &&do { if (!(top() == block_start_const(end()-1) && top
() == block_start_const(top()))) { (*g_assert_poison) = 'X';;
report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 612, "guarantee(" "top() == block_start_const(end()-1) && top() == block_start_const(top())"
") failed", "top should be start of unallocated block, if it exists"
); ::breakpoint(); } } while (0)
611 top() == block_start_const(top()),do { if (!(top() == block_start_const(end()-1) && top
() == block_start_const(top()))) { (*g_assert_poison) = 'X';;
report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 612, "guarantee(" "top() == block_start_const(end()-1) && top() == block_start_const(top())"
") failed", "top should be start of unallocated block, if it exists"
); ::breakpoint(); } } while (0)
612 "top should be start of unallocated block, if it exists")do { if (!(top() == block_start_const(end()-1) && top
() == block_start_const(top()))) { (*g_assert_poison) = 'X';;
report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 612, "guarantee(" "top() == block_start_const(end()-1) && top() == block_start_const(top())"
") failed", "top should be start of unallocated block, if it exists"
); ::breakpoint(); } } while (0);
613 }
614}
615
616void Space::oop_iterate(OopIterateClosure* blk) {
617 ObjectToOopClosure blk2(blk);
618 object_iterate(&blk2);
619}
620
621bool Space::obj_is_alive(const HeapWord* p) const {
622 assert (block_is_obj(p), "The address should point to an object")do { if (!(block_is_obj(p))) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 622, "assert(" "block_is_obj(p)" ") failed", "The address should point to an object"
); ::breakpoint(); } } while (0);
623 return true;
624}
625
626void ContiguousSpace::oop_iterate(OopIterateClosure* blk) {
627 if (is_empty()) return;
628 HeapWord* obj_addr = bottom();
629 HeapWord* t = top();
630 // Could call objects iterate, but this is easier.
631 while (obj_addr < t) {
632 obj_addr += cast_to_oop(obj_addr)->oop_iterate_size(blk);
633 }
634}
635
636void ContiguousSpace::object_iterate(ObjectClosure* blk) {
637 if (is_empty()) return;
638 object_iterate_from(bottom(), blk);
639}
640
641void ContiguousSpace::object_iterate_from(HeapWord* mark, ObjectClosure* blk) {
642 while (mark < top()) {
643 blk->do_object(cast_to_oop(mark));
644 mark += cast_to_oop(mark)->size();
645 }
646}
647
648// Very general, slow implementation.
649HeapWord* ContiguousSpace::block_start_const(const void* p) const {
650 assert(MemRegion(bottom(), end()).contains(p),do { if (!(MemRegion(bottom(), end()).contains(p))) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 652, "assert(" "MemRegion(bottom(), end()).contains(p)" ") failed"
, "p (" "0x%016" "l" "x" ") not in space [" "0x%016" "l" "x" ", "
"0x%016" "l" "x" ")", p2i(p), p2i(bottom()), p2i(end())); ::
breakpoint(); } } while (0)
651 "p (" PTR_FORMAT ") not in space [" PTR_FORMAT ", " PTR_FORMAT ")",do { if (!(MemRegion(bottom(), end()).contains(p))) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 652, "assert(" "MemRegion(bottom(), end()).contains(p)" ") failed"
, "p (" "0x%016" "l" "x" ") not in space [" "0x%016" "l" "x" ", "
"0x%016" "l" "x" ")", p2i(p), p2i(bottom()), p2i(end())); ::
breakpoint(); } } while (0)
652 p2i(p), p2i(bottom()), p2i(end()))do { if (!(MemRegion(bottom(), end()).contains(p))) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 652, "assert(" "MemRegion(bottom(), end()).contains(p)" ") failed"
, "p (" "0x%016" "l" "x" ") not in space [" "0x%016" "l" "x" ", "
"0x%016" "l" "x" ")", p2i(p), p2i(bottom()), p2i(end())); ::
breakpoint(); } } while (0);
653 if (p >= top()) {
654 return top();
655 } else {
656 HeapWord* last = bottom();
657 HeapWord* cur = last;
658 while (cur <= p) {
659 last = cur;
660 cur += cast_to_oop(cur)->size();
661 }
662 assert(oopDesc::is_oop(cast_to_oop(last)), PTR_FORMAT " should be an object start", p2i(last))do { if (!(oopDesc::is_oop(cast_to_oop(last)))) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 662, "assert(" "oopDesc::is_oop(cast_to_oop(last))" ") failed"
, "0x%016" "l" "x" " should be an object start", p2i(last)); ::
breakpoint(); } } while (0);
663 return last;
664 }
665}
666
667size_t ContiguousSpace::block_size(const HeapWord* p) const {
668 assert(MemRegion(bottom(), end()).contains(p),do { if (!(MemRegion(bottom(), end()).contains(p))) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 670, "assert(" "MemRegion(bottom(), end()).contains(p)" ") failed"
, "p (" "0x%016" "l" "x" ") not in space [" "0x%016" "l" "x" ", "
"0x%016" "l" "x" ")", p2i(p), p2i(bottom()), p2i(end())); ::
breakpoint(); } } while (0)
669 "p (" PTR_FORMAT ") not in space [" PTR_FORMAT ", " PTR_FORMAT ")",do { if (!(MemRegion(bottom(), end()).contains(p))) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 670, "assert(" "MemRegion(bottom(), end()).contains(p)" ") failed"
, "p (" "0x%016" "l" "x" ") not in space [" "0x%016" "l" "x" ", "
"0x%016" "l" "x" ")", p2i(p), p2i(bottom()), p2i(end())); ::
breakpoint(); } } while (0)
670 p2i(p), p2i(bottom()), p2i(end()))do { if (!(MemRegion(bottom(), end()).contains(p))) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 670, "assert(" "MemRegion(bottom(), end()).contains(p)" ") failed"
, "p (" "0x%016" "l" "x" ") not in space [" "0x%016" "l" "x" ", "
"0x%016" "l" "x" ")", p2i(p), p2i(bottom()), p2i(end())); ::
breakpoint(); } } while (0);
671 HeapWord* current_top = top();
672 assert(p <= current_top,do { if (!(p <= current_top)) { (*g_assert_poison) = 'X';;
report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 674, "assert(" "p <= current_top" ") failed", "p > current top - p: "
"0x%016" "l" "x" ", current top: " "0x%016" "l" "x", p2i(p),
p2i(current_top)); ::breakpoint(); } } while (0)
673 "p > current top - p: " PTR_FORMAT ", current top: " PTR_FORMAT,do { if (!(p <= current_top)) { (*g_assert_poison) = 'X';;
report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 674, "assert(" "p <= current_top" ") failed", "p > current top - p: "
"0x%016" "l" "x" ", current top: " "0x%016" "l" "x", p2i(p),
p2i(current_top)); ::breakpoint(); } } while (0)
674 p2i(p), p2i(current_top))do { if (!(p <= current_top)) { (*g_assert_poison) = 'X';;
report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 674, "assert(" "p <= current_top" ") failed", "p > current top - p: "
"0x%016" "l" "x" ", current top: " "0x%016" "l" "x", p2i(p),
p2i(current_top)); ::breakpoint(); } } while (0);
675 assert(p == current_top || oopDesc::is_oop(cast_to_oop(p)),do { if (!(p == current_top || oopDesc::is_oop(cast_to_oop(p)
))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 678, "assert(" "p == current_top || oopDesc::is_oop(cast_to_oop(p))"
") failed", "p (" "0x%016" "l" "x" ") is not a block start - "
"current_top: " "0x%016" "l" "x" ", is_oop: %s", p2i(p), p2i
(current_top), ((oopDesc::is_oop(cast_to_oop(p))) ? "true" : "false"
)); ::breakpoint(); } } while (0)
676 "p (" PTR_FORMAT ") is not a block start - "do { if (!(p == current_top || oopDesc::is_oop(cast_to_oop(p)
))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 678, "assert(" "p == current_top || oopDesc::is_oop(cast_to_oop(p))"
") failed", "p (" "0x%016" "l" "x" ") is not a block start - "
"current_top: " "0x%016" "l" "x" ", is_oop: %s", p2i(p), p2i
(current_top), ((oopDesc::is_oop(cast_to_oop(p))) ? "true" : "false"
)); ::breakpoint(); } } while (0)
677 "current_top: " PTR_FORMAT ", is_oop: %s",do { if (!(p == current_top || oopDesc::is_oop(cast_to_oop(p)
))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 678, "assert(" "p == current_top || oopDesc::is_oop(cast_to_oop(p))"
") failed", "p (" "0x%016" "l" "x" ") is not a block start - "
"current_top: " "0x%016" "l" "x" ", is_oop: %s", p2i(p), p2i
(current_top), ((oopDesc::is_oop(cast_to_oop(p))) ? "true" : "false"
)); ::breakpoint(); } } while (0)
678 p2i(p), p2i(current_top), BOOL_TO_STR(oopDesc::is_oop(cast_to_oop(p))))do { if (!(p == current_top || oopDesc::is_oop(cast_to_oop(p)
))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 678, "assert(" "p == current_top || oopDesc::is_oop(cast_to_oop(p))"
") failed", "p (" "0x%016" "l" "x" ") is not a block start - "
"current_top: " "0x%016" "l" "x" ", is_oop: %s", p2i(p), p2i
(current_top), ((oopDesc::is_oop(cast_to_oop(p))) ? "true" : "false"
)); ::breakpoint(); } } while (0);
679 if (p < current_top) {
680 return cast_to_oop(p)->size();
681 } else {
682 assert(p == current_top, "just checking")do { if (!(p == current_top)) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 682, "assert(" "p == current_top" ") failed", "just checking"
); ::breakpoint(); } } while (0);
683 return pointer_delta(end(), (HeapWord*) p);
684 }
685}
686
687// This version requires locking.
688inline HeapWord* ContiguousSpace::allocate_impl(size_t size) {
689 assert(Heap_lock->owned_by_self() ||do { if (!(Heap_lock->owned_by_self() || (SafepointSynchronize
::is_at_safepoint() && Thread::current()->is_VM_thread
()))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 691, "assert(" "Heap_lock->owned_by_self() || (SafepointSynchronize::is_at_safepoint() && Thread::current()->is_VM_thread())"
") failed", "not locked"); ::breakpoint(); } } while (0)
690 (SafepointSynchronize::is_at_safepoint() && Thread::current()->is_VM_thread()),do { if (!(Heap_lock->owned_by_self() || (SafepointSynchronize
::is_at_safepoint() && Thread::current()->is_VM_thread
()))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 691, "assert(" "Heap_lock->owned_by_self() || (SafepointSynchronize::is_at_safepoint() && Thread::current()->is_VM_thread())"
") failed", "not locked"); ::breakpoint(); } } while (0)
691 "not locked")do { if (!(Heap_lock->owned_by_self() || (SafepointSynchronize
::is_at_safepoint() && Thread::current()->is_VM_thread
()))) { (*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 691, "assert(" "Heap_lock->owned_by_self() || (SafepointSynchronize::is_at_safepoint() && Thread::current()->is_VM_thread())"
") failed", "not locked"); ::breakpoint(); } } while (0);
692 HeapWord* obj = top();
693 if (pointer_delta(end(), obj) >= size) {
694 HeapWord* new_top = obj + size;
695 set_top(new_top);
696 assert(is_aligned(obj) && is_aligned(new_top), "checking alignment")do { if (!(is_aligned(obj) && is_aligned(new_top))) {
(*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 696, "assert(" "is_aligned(obj) && is_aligned(new_top)"
") failed", "checking alignment"); ::breakpoint(); } } while
(0);
697 return obj;
698 } else {
699 return NULL__null;
700 }
701}
702
703// This version is lock-free.
704inline HeapWord* ContiguousSpace::par_allocate_impl(size_t size) {
705 do {
706 HeapWord* obj = top();
707 if (pointer_delta(end(), obj) >= size) {
708 HeapWord* new_top = obj + size;
709 HeapWord* result = Atomic::cmpxchg(top_addr(), obj, new_top);
710 // result can be one of two:
711 // the old top value: the exchange succeeded
712 // otherwise: the new value of the top is returned.
713 if (result == obj) {
714 assert(is_aligned(obj) && is_aligned(new_top), "checking alignment")do { if (!(is_aligned(obj) && is_aligned(new_top))) {
(*g_assert_poison) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 714, "assert(" "is_aligned(obj) && is_aligned(new_top)"
") failed", "checking alignment"); ::breakpoint(); } } while
(0);
715 return obj;
716 }
717 } else {
718 return NULL__null;
719 }
720 } while (true);
721}
722
723// Requires locking.
724HeapWord* ContiguousSpace::allocate(size_t size) {
725 return allocate_impl(size);
726}
727
728// Lock-free.
729HeapWord* ContiguousSpace::par_allocate(size_t size) {
730 return par_allocate_impl(size);
731}
732
733void OffsetTableContigSpace::initialize_threshold() {
734 _offsets.initialize_threshold();
735}
736
737void OffsetTableContigSpace::alloc_block(HeapWord* start, HeapWord* end) {
738 _offsets.alloc_block(start, end);
739}
740
741OffsetTableContigSpace::OffsetTableContigSpace(BlockOffsetSharedArray* sharedOffsetArray,
742 MemRegion mr) :
743 _offsets(sharedOffsetArray, mr),
744 _par_alloc_lock(Mutex::safepoint, "OffsetTableContigSpaceParAlloc_lock", true)
745{
746 _offsets.set_contig_space(this);
747 initialize(mr, SpaceDecorator::Clear, SpaceDecorator::Mangle);
748}
749
750#define OBJ_SAMPLE_INTERVAL0 0
751#define BLOCK_SAMPLE_INTERVAL100 100
752
753void OffsetTableContigSpace::verify() const {
754 HeapWord* p = bottom();
755 HeapWord* prev_p = NULL__null;
756 int objs = 0;
757 int blocks = 0;
758
759 if (VerifyObjectStartArray) {
760 _offsets.verify();
761 }
762
763 while (p < top()) {
764 size_t size = cast_to_oop(p)->size();
765 // For a sampling of objects in the space, find it using the
766 // block offset table.
767 if (blocks == BLOCK_SAMPLE_INTERVAL100) {
768 guarantee(p == block_start_const(p + (size/2)),do { if (!(p == block_start_const(p + (size/2)))) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 769, "guarantee(" "p == block_start_const(p + (size/2))" ") failed"
, "check offset computation"); ::breakpoint(); } } while (0)
769 "check offset computation")do { if (!(p == block_start_const(p + (size/2)))) { (*g_assert_poison
) = 'X';; report_vm_error("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 769, "guarantee(" "p == block_start_const(p + (size/2))" ") failed"
, "check offset computation"); ::breakpoint(); } } while (0);
770 blocks = 0;
771 } else {
772 blocks++;
773 }
774
775 if (objs == OBJ_SAMPLE_INTERVAL0) {
776 oopDesc::verify(cast_to_oop(p));
777 objs = 0;
778 } else {
779 objs++;
780 }
781 prev_p = p;
Value stored to 'prev_p' is never read
782 p += size;
783 }
784 guarantee(p == top(), "end of last object must match end of space")do { if (!(p == top())) { (*g_assert_poison) = 'X';; report_vm_error
("/home/daniel/Projects/java/jdk/src/hotspot/share/gc/shared/space.cpp"
, 784, "guarantee(" "p == top()" ") failed", "end of last object must match end of space"
); ::breakpoint(); } } while (0);
785}
786
787
788size_t TenuredSpace::allowed_dead_ratio() const {
789 return MarkSweepDeadRatio;
790}