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Add inline floating point comparisons for comparison operators to x64 platform.

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Review URL: http://codereview.chromium.org/1703019

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4545 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
whesse@chromium.org 2010-04-29 11:44:17 +00:00
parent a0c1310479
commit 3e689b5283
1 changed files with 66 additions and 17 deletions
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83
src/x64/codegen-x64.cc
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@ -5708,7 +5708,7 @@ void CodeGenerator::Comparison(AstNode* node,
CompareStub stub(cc, strict, kCantBothBeNaN);
Result result = frame_->CallStub(&stub, &left_side, &right_side);
result.ToRegister();
__ SmiCompare(result.reg(), Smi::FromInt(0));
__ testq(result.reg(), result.reg());
result.Unuse();
dest->true_target()->Branch(cc);
dest->false_target()->Jump();
@ -5805,13 +5805,9 @@ void CodeGenerator::Comparison(AstNode* node,
GenerateInlineNumberComparison(&left_side, &right_side, cc, dest);
}
// Call the compare stub.
// TODO(whesse@chromium.org): Enable the inlining flag once
// GenerateInlineNumberComparison is implemented.
CompareStub stub(cc, strict, nan_info, true || !inline_number_compare);
CompareStub stub(cc, strict, nan_info, !inline_number_compare);
Result answer = frame_->CallStub(&stub, &left_side, &right_side);
// The result is a Smi, which is negative, zero, or positive.
__ SmiTest(answer.reg()); // Sets both zero and sign flag.
__ testq(answer.reg(), answer.reg()); // Sets both zero and sign flag.
answer.Unuse();
dest->Split(cc);
} else {
@ -5839,12 +5835,9 @@ void CodeGenerator::Comparison(AstNode* node,
GenerateInlineNumberComparison(&left_side, &right_side, cc, dest);
}
// Call the compare stub.
// TODO(whesse@chromium.org): Enable the inlining flag once
// GenerateInlineNumberComparison is implemented.
CompareStub stub(cc, strict, nan_info, true || !inline_number_compare);
CompareStub stub(cc, strict, nan_info, !inline_number_compare);
Result answer = frame_->CallStub(&stub, &left_side, &right_side);
__ SmiTest(answer.reg()); // Sets both zero and sign flags.
__ testq(answer.reg(), answer.reg()); // Sets both zero and sign flags.
answer.Unuse();
dest->true_target()->Branch(cc);
dest->false_target()->Jump();
@ -5861,14 +5854,70 @@ void CodeGenerator::Comparison(AstNode* node,
}
// Load a comparison operand into into a XMM register. Jump to not_numbers jump
// target passing the left and right result if the operand is not a number.
static void LoadComparisonOperand(MacroAssembler* masm_,
Result* operand,
XMMRegister xmm_reg,
Result* left_side,
Result* right_side,
JumpTarget* not_numbers) {
Label done;
if (operand->type_info().IsDouble()) {
// Operand is known to be a heap number, just load it.
__ movsd(xmm_reg, FieldOperand(operand->reg(), HeapNumber::kValueOffset));
} else if (operand->type_info().IsSmi()) {
// Operand is known to be a smi. Convert it to double and keep the original
// smi.
__ SmiToInteger32(kScratchRegister, operand->reg());
__ cvtlsi2sd(xmm_reg, kScratchRegister);
} else {
// Operand type not known, check for smi or heap number.
Label smi;
__ JumpIfSmi(operand->reg(), &smi);
if (!operand->type_info().IsNumber()) {
__ LoadRoot(kScratchRegister, Heap::kHeapNumberMapRootIndex);
__ cmpq(FieldOperand(operand->reg(), HeapObject::kMapOffset),
kScratchRegister);
not_numbers->Branch(not_equal, left_side, right_side, taken);
}
__ movsd(xmm_reg, FieldOperand(operand->reg(), HeapNumber::kValueOffset));
__ jmp(&done);
__ bind(&smi);
// Comvert smi to float and keep the original smi.
__ SmiToInteger32(kScratchRegister, operand->reg());
__ cvtlsi2sd(xmm_reg, kScratchRegister);
__ jmp(&done);
}
__ bind(&done);
}
void CodeGenerator::GenerateInlineNumberComparison(Result* left_side,
Result* right_side,
Condition cc,
ControlDestination* dest) {
ASSERT(left_side->is_register());
ASSERT(right_side->is_register());
// TODO(whesse@chromium.org): Implement this function, and enable the
// corresponding flags in the CompareStub.
JumpTarget not_numbers;
// Load left and right operand into registers xmm0 and xmm1 and compare.
LoadComparisonOperand(masm_, left_side, xmm0, left_side, right_side,
&not_numbers);
LoadComparisonOperand(masm_, right_side, xmm1, left_side, right_side,
&not_numbers);
__ comisd(xmm0, xmm1);
// Bail out if a NaN is involved.
not_numbers.Branch(parity_even, left_side, right_side);
// Split to destination targets based on comparison.
left_side->Unuse();
right_side->Unuse();
dest->true_target()->Branch(DoubleCondition(cc));
dest->false_target()->Jump();
not_numbers.Bind(left_side, right_side);
}
@ -7991,12 +8040,12 @@ static int NegativeComparisonResult(Condition cc) {
void CompareStub::Generate(MacroAssembler* masm) {
Label call_builtin, done;
// The compare stub returns a positive, negative, or zero 64-bit integer
// value in rax, corresponding to result of comparing the two inputs.
// NOTICE! This code is only reached after a smi-fast-case check, so
// it is certain that at least one operand isn't a smi.
// Identical objects can be compared fast, but there are some tricky cases
// for NaN and undefined.
// Two identical objects are equal unless they are both NaN or undefined.
{
Label not_identical;
__ cmpq(rax, rdx);