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

[turbofan] Remove redundant helper AddIsSafe.

Browse Source 
Use the base::bits::SignedAddOverflow32() function instead, which
performs an addition and checks for overflow.

Bug: v8:5267, v8:7109
Change-Id: I20a5316957a3f72131d318282e8b8e8bb500b4a7
Reviewed-on: https://chromium-review.googlesource.com/797451
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51028}
This commit is contained in:
Benedikt Meurer 2017-11-29 19:17:21 +01:00 committed by Commit Bot
parent 954146a5cf
commit aa47fd43c4
1 changed files with 6 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

19
src/compiler/types.cc
View File

@ -615,11 +615,6 @@ bool UnionType::Wellformed() {
// -----------------------------------------------------------------------------
// Union and intersection
static bool AddIsSafe(int x, int y) {
return x >= 0 ? y <= std::numeric_limits<int>::max() - x
: y >= std::numeric_limits<int>::min() - x;
}
Type* Type::Intersect(Type* type1, Type* type2, Zone* zone) {
// Fast case: bit sets.
if (type1->IsBitset() && type2->IsBitset()) {
@ -647,10 +642,9 @@ Type* Type::Intersect(Type* type1, Type* type2, Zone* zone) {
bitset bits = type1->BitsetGlb() & type2->BitsetGlb();
int size1 = type1->IsUnion() ? type1->AsUnion()->Length() : 1;
int size2 = type2->IsUnion() ? type2->AsUnion()->Length() : 1;
if (!AddIsSafe(size1, size2)) return Any();
int size = size1 + size2;
if (!AddIsSafe(size, 2)) return Any();
size += 2;
int size;
if (base::bits::SignedAddOverflow32(size1, size2, &size)) return Any();
if (base::bits::SignedAddOverflow32(size, 2, &size)) return Any();
Type* result_type = UnionType::New(size, zone);
UnionType* result = result_type->AsUnion();
size = 0;
@ -849,10 +843,9 @@ Type* Type::Union(Type* type1, Type* type2, Zone* zone) {
// Slow case: create union.
int size1 = type1->IsUnion() ? type1->AsUnion()->Length() : 1;
int size2 = type2->IsUnion() ? type2->AsUnion()->Length() : 1;
if (!AddIsSafe(size1, size2)) return Any();
int size = size1 + size2;
if (!AddIsSafe(size, 2)) return Any();
size += 2;
int size;
if (base::bits::SignedAddOverflow32(size1, size2, &size)) return Any();
if (base::bits::SignedAddOverflow32(size, 2, &size)) return Any();
Type* result_type = UnionType::New(size, zone);
UnionType* result = result_type->AsUnion();
size = 0;