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X87: [ic] Also collect known map for relational comparison.

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port e56f265f6d (r30852).

original commit message:

    Previously we only collected the known map for equality comparisons. But
    if we also collect it for relational comparisons, we can inline a fast
    path of ToPrimitive on the objects, which is especially interesting
    since both sides have the same map.

    For now we only inline a very limited subset of ToPrimitive in
    Crankshaft, which is when the receiver map (and its prototype chain)
    doesn't have @@toPrimitive, and both valueOf and toString are the
    default versions on the %ObjectPrototype%. In this case the relational
    comparison would reduce to a string comparison of "[object CLASS]" with
    itself and so we can reduce that to a boolean constant plus map checks
    on both left and right hand side, plus code dependencies on the
    prototype chain. This repairs the regression on box2d.

BUG=

Review URL: https://codereview.chromium.org/1342243005

Cr-Commit-Position: refs/heads/master@{#30897}
This commit is contained in:
chunyang.dai 2015-09-23 20:34:45 -07:00 committed by Commit bot
parent 5e6f7a6ccb
commit 687ef62eb5
1 changed files with 15 additions and 6 deletions
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21
src/x87/code-stubs-x87.cc
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@ -3426,15 +3426,24 @@ void CompareICStub::GenerateKnownObjects(MacroAssembler* masm) {
__ JumpIfSmi(ecx, &miss, Label::kNear);
__ GetWeakValue(edi, cell);
__ mov(ecx, FieldOperand(eax, HeapObject::kMapOffset));
__ mov(ebx, FieldOperand(edx, HeapObject::kMapOffset));
__ cmp(ecx, edi);
__ cmp(edi, FieldOperand(eax, HeapObject::kMapOffset));
__ j(not_equal, &miss, Label::kNear);
__ cmp(ebx, edi);
__ cmp(edi, FieldOperand(edx, HeapObject::kMapOffset));
__ j(not_equal, &miss, Label::kNear);
__ sub(eax, edx);
__ ret(0);
if (Token::IsEqualityOp(op())) {
__ sub(eax, edx);
__ ret(0);
} else if (is_strong(strength())) {
__ TailCallRuntime(Runtime::kThrowStrongModeImplicitConversion, 0, 1);
} else {
__ PopReturnAddressTo(ecx);
__ Push(edx);
__ Push(eax);
__ Push(Immediate(Smi::FromInt(NegativeComparisonResult(GetCondition()))));
__ PushReturnAddressFrom(ecx);
__ TailCallRuntime(Runtime::kCompare, 3, 1);
}
__ bind(&miss);
GenerateMiss(masm);