AuroraMiddleware/v8
1
0
Fork 0
Code Issues 2 Pull Requests Releases Wiki Activity

[ext-code-space] Fix DCHECKs in VisitSpillSlot

Browse Source 
... to match new encoding of the forwarding pointers.

Bug: v8:11880, chromium:1393256
Change-Id: I8bc8183c22ef8933c02470d5c8ed77cf83489e0f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/4069706
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Auto-Submit: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#84601}
This commit is contained in:
Igor Sheludko 2022-12-01 16:05:49 +01:00 committed by V8 LUCI CQ
parent 56b455ea57
commit 32b7dc86a7
2 changed files with 14 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

4
src/execution/frames.cc
View File

@ -1119,8 +1119,8 @@ void VisitSpillSlot(Isolate* isolate, RootVisitor* v,
? map_word.ToForwardingAddress(raw)
: raw;
bool is_self_forwarded =
forwarded.map_word(cage_base, kRelaxedLoad).ptr() ==
forwarded.address();
forwarded.map_word(cage_base, kRelaxedLoad) ==
MapWord::FromForwardingAddress(forwarded, forwarded);
if (is_self_forwarded) {
// The object might be in a self-forwarding state if it's located
// in new large object space. GC will fix this at a later stage.

14
src/objects/objects.h
View File

@ -904,7 +904,17 @@ class MapWord {
// View this map word as a forwarding address.
inline HeapObject ToForwardingAddress(HeapObject map_word_host);
inline Address ptr() { return value_; }
constexpr inline Address ptr() const { return value_; }
// When pointer compression is enabled, MapWord is uniquely identified by
// the lower 32 bits. On the other hand full-value comparison is not correct
// because map word in a forwarding state might have corrupted upper part.
constexpr bool operator==(MapWord other) const {
return static_cast<Tagged_t>(ptr()) == static_cast<Tagged_t>(other.ptr());
}
constexpr bool operator!=(MapWord other) const {
return static_cast<Tagged_t>(ptr()) != static_cast<Tagged_t>(other.ptr());
}
#ifdef V8_MAP_PACKING
static constexpr Address Pack(Address map) {
@ -929,7 +939,7 @@ class MapWord {
template <typename TFieldType, int kFieldOffset, typename CompressionScheme>
friend class TaggedField;
explicit MapWord(Address value) : value_(value) {}
explicit constexpr MapWord(Address value) : value_(value) {}
Address value_;
};