AuroraMiddleware/v8
1
0
Fork 0
Code Issues 2 Pull Requests Releases Wiki Activity

Delay the pushing of arguments until just before calling runtime in CompareStub.

Browse Source 
This will allow jumps to runtime that skip useless tests.
Review URL: http://codereview.chromium.org/3016004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5097 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
whesse@chromium.org 2010-07-19 13:35:41 +00:00
parent 793d0a92b9
commit 96a7cc4a38
2 changed files with 28 additions and 38 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
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;
@ -11864,7 +11858,7 @@ 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);
@ -11875,22 +11869,20 @@ void CompareStub::Generate(MacroAssembler* masm) {
__ 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 +11894,7 @@ 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 +11909,7 @@ 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 +11962,12 @@ 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 +13544,19 @@ 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 +13586,10 @@ 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)