AuroraMiddleware/v8
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[turbofan] Remove redundant helper AddIsSafe.

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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
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19
src/compiler/types.cc
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@ -615,11 +615,6 @@ bool UnionType::Wellformed() {
// ----------------------------------------------------------------------------- // -----------------------------------------------------------------------------
// Union and intersection // 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) { Type* Type::Intersect(Type* type1, Type* type2, Zone* zone) {
// Fast case: bit sets. // Fast case: bit sets.
if (type1->IsBitset() && type2->IsBitset()) { if (type1->IsBitset() && type2->IsBitset()) {
@ -647,10 +642,9 @@ Type* Type::Intersect(Type* type1, Type* type2, Zone* zone) {
bitset bits = type1->BitsetGlb() & type2->BitsetGlb(); bitset bits = type1->BitsetGlb() & type2->BitsetGlb();
int size1 = type1->IsUnion() ? type1->AsUnion()->Length() : 1; int size1 = type1->IsUnion() ? type1->AsUnion()->Length() : 1;
int size2 = type2->IsUnion() ? type2->AsUnion()->Length() : 1; int size2 = type2->IsUnion() ? type2->AsUnion()->Length() : 1;
if (!AddIsSafe(size1, size2)) return Any(); int size;
int size = size1 + size2; if (base::bits::SignedAddOverflow32(size1, size2, &size)) return Any();
if (!AddIsSafe(size, 2)) return Any(); if (base::bits::SignedAddOverflow32(size, 2, &size)) return Any();
size += 2;
Type* result_type = UnionType::New(size, zone); Type* result_type = UnionType::New(size, zone);
UnionType* result = result_type->AsUnion(); UnionType* result = result_type->AsUnion();
size = 0; size = 0;
@ -849,10 +843,9 @@ Type* Type::Union(Type* type1, Type* type2, Zone* zone) {
// Slow case: create union. // Slow case: create union.
int size1 = type1->IsUnion() ? type1->AsUnion()->Length() : 1; int size1 = type1->IsUnion() ? type1->AsUnion()->Length() : 1;
int size2 = type2->IsUnion() ? type2->AsUnion()->Length() : 1; int size2 = type2->IsUnion() ? type2->AsUnion()->Length() : 1;
if (!AddIsSafe(size1, size2)) return Any(); int size;
int size = size1 + size2; if (base::bits::SignedAddOverflow32(size1, size2, &size)) return Any();
if (!AddIsSafe(size, 2)) return Any(); if (base::bits::SignedAddOverflow32(size, 2, &size)) return Any();
size += 2;
Type* result_type = UnionType::New(size, zone); Type* result_type = UnionType::New(size, zone);
UnionType* result = result_type->AsUnion(); UnionType* result = result_type->AsUnion();
size = 0; size = 0;