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Port inlined quick equality check for non-NaN to x64.

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Review URL: http://codereview.chromium.org/1756002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4463 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
whesse@chromium.org 2010-04-21 13:33:36 +00:00
parent 1a31f9a2f7
commit 9cf54367e9
2 changed files with 33 additions and 7 deletions
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6
src/ia32/codegen-ia32.cc
View File

@ -2773,11 +2773,7 @@ void CodeGenerator::Comparison(AstNode* node,
// number comparison in the stub if it was inlined. // number comparison in the stub if it was inlined.
CompareStub stub(cc, strict, nan_info, !inline_number_compare); CompareStub stub(cc, strict, nan_info, !inline_number_compare);
Result answer = frame_->CallStub(&stub, &left_side, &right_side); Result answer = frame_->CallStub(&stub, &left_side, &right_side);
if (cc == equal) { __ test(answer.reg(), Operand(answer.reg()));
__ test(answer.reg(), Operand(answer.reg()));
} else {
__ cmp(answer.reg(), 0);
}
answer.Unuse(); answer.Unuse();
dest->Split(cc); dest->Split(cc);
} else { } else {

34
src/x64/codegen-x64.cc
View File

@ -5297,6 +5297,15 @@ void CodeGenerator::LoadTypeofExpression(Expression* expr) {
} }
static bool CouldBeNaN(const Result& result) {
if (result.type_info().IsSmi()) return false;
if (result.type_info().IsInteger32()) return false;
if (!result.is_constant()) return true;
if (!result.handle()->IsHeapNumber()) return false;
return isnan(HeapNumber::cast(*result.handle())->value());
}
void CodeGenerator::Comparison(AstNode* node, void CodeGenerator::Comparison(AstNode* node,
Condition cc, Condition cc,
bool strict, bool strict,
@ -5614,15 +5623,29 @@ void CodeGenerator::Comparison(AstNode* node,
right_side.Unuse(); right_side.Unuse();
dest->Split(cc); dest->Split(cc);
} }
} else { // Neither side is a constant Smi or null. } else {
// Neither side is a constant Smi, constant 1-char string, or constant null.
// If either side is a non-smi constant, skip the smi check. // If either side is a non-smi constant, skip the smi check.
bool known_non_smi = bool known_non_smi =
(left_side.is_constant() && !left_side.handle()->IsSmi()) || (left_side.is_constant() && !left_side.handle()->IsSmi()) ||
(right_side.is_constant() && !right_side.handle()->IsSmi()); (right_side.is_constant() && !right_side.handle()->IsSmi());
NaNInformation nan_info =
(CouldBeNaN(left_side) && CouldBeNaN(right_side)) ?
kBothCouldBeNaN :
kCantBothBeNaN;
left_side.ToRegister(); left_side.ToRegister();
right_side.ToRegister(); right_side.ToRegister();
if (known_non_smi) { if (known_non_smi) {
// If at least one of the objects is not NaN, then if the objects
// are identical, they are equal.
if (nan_info == kCantBothBeNaN && cc == equal) {
__ cmpq(left_side.reg(), right_side.reg());
dest->true_target()->Branch(equal);
}
// When non-smi, call out to the compare stub. // When non-smi, call out to the compare stub.
CompareStub stub(cc, strict); CompareStub stub(cc, strict);
Result answer = frame_->CallStub(&stub, &left_side, &right_side); Result answer = frame_->CallStub(&stub, &left_side, &right_side);
@ -5642,7 +5665,14 @@ void CodeGenerator::Comparison(AstNode* node,
Condition both_smi = masm_->CheckBothSmi(left_reg, right_reg); Condition both_smi = masm_->CheckBothSmi(left_reg, right_reg);
is_smi.Branch(both_smi); is_smi.Branch(both_smi);
// When non-smi, call out to the compare stub. // When non-smi, call out to the compare stub, after inlined checks.
// If at least one of the objects is not NaN, then if the objects
// are identical, they are equal.
if (nan_info == kCantBothBeNaN && cc == equal) {
__ cmpq(left_side.reg(), right_side.reg());
dest->true_target()->Branch(equal);
}
CompareStub stub(cc, strict); CompareStub stub(cc, strict);
Result answer = frame_->CallStub(&stub, &left_side, &right_side); Result answer = frame_->CallStub(&stub, &left_side, &right_side);
__ SmiTest(answer.reg()); // Sets both zero and sign flags. __ SmiTest(answer.reg()); // Sets both zero and sign flags.