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Stop pushing arguments onto the stack in CompareStub until just before calling runtime.

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This is a fixed version of change 5097, which had the problem that LoadFloatOperands tried to load the arguments from the stack.
Review URL: http://codereview.chromium.org/3040010

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5103 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
whesse@chromium.org 2010-07-20 12:41:43 +00:00
parent f32e2b7093
commit 54f68eacbf
2 changed files with 30 additions and 39 deletions
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41
src/ia32/codegen-ia32.cc
View File

@ -11839,12 +11839,6 @@ void CompareStub::Generate(MacroAssembler* masm) {
__ bind(&slow);
}
// Push arguments below the return address.
__ pop(ecx);
__ push(eax);
__ push(edx);
__ push(ecx);
// Generate the number comparison code.
if (include_number_compare_) {
Label non_number_comparison;
@ -11864,33 +11858,32 @@ void CompareStub::Generate(MacroAssembler* masm) {
__ cmov(above, eax, Operand(ecx));
__ mov(ecx, Immediate(Smi::FromInt(-1)));
__ cmov(below, eax, Operand(ecx));
__ ret(2 * kPointerSize);
__ ret(0);
} else {
FloatingPointHelper::CheckFloatOperands(
masm, &non_number_comparison, ebx);
FloatingPointHelper::LoadFloatOperands(masm, ecx);
FloatingPointHelper::LoadFloatOperand(masm, eax);
FloatingPointHelper::LoadFloatOperand(masm, edx);
__ FCmp();
// Don't base result on EFLAGS when a NaN is involved.
__ j(parity_even, &unordered, not_taken);
Label below_label, above_label;
// Return a result of -1, 0, or 1, based on EFLAGS. In all cases remove
// two arguments from the stack as they have been pushed in preparation
// of a possible runtime call.
// Return a result of -1, 0, or 1, based on EFLAGS.
__ j(below, &below_label, not_taken);
__ j(above, &above_label, not_taken);
__ xor_(eax, Operand(eax));
__ ret(2 * kPointerSize);
__ ret(0);
__ bind(&below_label);
__ mov(eax, Immediate(Smi::FromInt(-1)));
__ ret(2 * kPointerSize);
__ ret(0);
__ bind(&above_label);
__ mov(eax, Immediate(Smi::FromInt(1)));
__ ret(2 * kPointerSize);
__ ret(0);
}
// If one of the numbers was NaN, then the result is always false.
@ -11902,7 +11895,7 @@ void CompareStub::Generate(MacroAssembler* masm) {
} else {
__ mov(eax, Immediate(Smi::FromInt(-1)));
}
__ ret(2 * kPointerSize); // eax, edx were pushed
__ ret(0);
// The number comparison code did not provide a valid result.
__ bind(&non_number_comparison);
@ -11917,7 +11910,7 @@ void CompareStub::Generate(MacroAssembler* masm) {
// We've already checked for object identity, so if both operands
// are symbols they aren't equal. Register eax already holds a
// non-zero value, which indicates not equal, so just return.
__ ret(2 * kPointerSize);
__ ret(0);
}
__ bind(&check_for_strings);
@ -11970,14 +11963,12 @@ void CompareStub::Generate(MacroAssembler* masm) {
__ bind(&return_unequal);
// Return non-equal by returning the non-zero object pointer in eax,
// or return equal if we fell through to here.
__ ret(2 * kPointerSize); // rax, rdx were pushed
__ ret(0); // rax, rdx were pushed
__ bind(&not_both_objects);
}
// must swap argument order
// Push arguments below the return address.
__ pop(ecx);
__ pop(edx);
__ pop(eax);
__ push(edx);
__ push(eax);
@ -13554,19 +13545,19 @@ void StringCompareStub::GenerateCompareFlatAsciiStrings(MacroAssembler* masm,
ASSERT_EQ(0, EQUAL);
ASSERT_EQ(0, kSmiTag);
__ Set(eax, Immediate(Smi::FromInt(EQUAL)));
__ ret(2 * kPointerSize);
__ ret(0);
__ bind(&result_not_equal);
__ j(greater, &result_greater);
// Result is LESS.
__ Set(eax, Immediate(Smi::FromInt(LESS)));
__ ret(2 * kPointerSize);
__ ret(0);
// Result is GREATER.
__ bind(&result_greater);
__ Set(eax, Immediate(Smi::FromInt(GREATER)));
__ ret(2 * kPointerSize);
__ ret(0);
}
@ -13596,6 +13587,10 @@ void StringCompareStub::Generate(MacroAssembler* masm) {
__ JumpIfNotBothSequentialAsciiStrings(edx, eax, ecx, ebx, &runtime);
// Compare flat ascii strings.
// Drop arguments from the stack.
__ pop(ecx);
__ add(Operand(esp), Immediate(2 * kPointerSize));
__ push(ecx);
GenerateCompareFlatAsciiStrings(masm, edx, eax, ecx, ebx, edi);
// Call the runtime; it returns -1 (less), 0 (equal), or 1 (greater)

28
src/x64/codegen-x64.cc
View File

@ -10288,12 +10288,6 @@ void CompareStub::Generate(MacroAssembler* masm) {
__ bind(&slow);
}
// Push arguments below the return address to prepare jump to builtin.
__ pop(rcx);
__ push(rax);
__ push(rdx);
__ push(rcx);
// Generate the number comparison code.
if (include_number_compare_) {
Label non_number_comparison;
@ -10309,7 +10303,7 @@ void CompareStub::Generate(MacroAssembler* masm) {
__ setcc(above, rax);
__ setcc(below, rcx);
__ subq(rax, rcx);
__ ret(2 * kPointerSize); // rax, rdx were pushed
__ ret(0);
// If one of the numbers was NaN, then the result is always false.
// The cc is never not-equal.
@ -10320,7 +10314,7 @@ void CompareStub::Generate(MacroAssembler* masm) {
} else {
__ Set(rax, -1);
}
__ ret(2 * kPointerSize); // rax, rdx were pushed
__ ret(0);
// The number comparison code did not provide a valid result.
__ bind(&non_number_comparison);
@ -10335,7 +10329,7 @@ void CompareStub::Generate(MacroAssembler* masm) {
// We've already checked for object identity, so if both operands
// are symbols they aren't equal. Register eax (not rax) already holds a
// non-zero value, which indicates not equal, so just return.
__ ret(2 * kPointerSize);
__ ret(0);
}
__ bind(&check_for_strings);
@ -10386,14 +10380,12 @@ void CompareStub::Generate(MacroAssembler* masm) {
__ bind(&return_unequal);
// Return non-equal by returning the non-zero object pointer in eax,
// or return equal if we fell through to here.
__ ret(2 * kPointerSize); // rax, rdx were pushed
__ ret(0);
__ bind(&not_both_objects);
}
// must swap argument order
// Push arguments below the return address to prepare jump to builtin.
__ pop(rcx);
__ pop(rdx);
__ pop(rax);
__ push(rdx);
__ push(rax);
@ -11970,7 +11962,7 @@ void StringCompareStub::GenerateCompareFlatAsciiStrings(MacroAssembler* masm,
// Result is EQUAL.
__ Move(rax, Smi::FromInt(EQUAL));
__ ret(2 * kPointerSize);
__ ret(0);
Label result_greater;
__ bind(&result_not_equal);
@ -11979,12 +11971,12 @@ void StringCompareStub::GenerateCompareFlatAsciiStrings(MacroAssembler* masm,
// Result is LESS.
__ Move(rax, Smi::FromInt(LESS));
__ ret(2 * kPointerSize);
__ ret(0);
// Result is GREATER.
__ bind(&result_greater);
__ Move(rax, Smi::FromInt(GREATER));
__ ret(2 * kPointerSize);
__ ret(0);
}
@ -12014,6 +12006,10 @@ void StringCompareStub::Generate(MacroAssembler* masm) {
// Inline comparison of ascii strings.
__ IncrementCounter(&Counters::string_compare_native, 1);
// Drop arguments from the stack
__ pop(rcx);
__ addq(rsp, Immediate(2 * kPointerSize));
__ push(rcx);
GenerateCompareFlatAsciiStrings(masm, rdx, rax, rcx, rbx, rdi, r8);
// Call the runtime; it returns -1 (less), 0 (equal), or 1 (greater)