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Inline mod for integer powers of 2.

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Review URL: http://codereview.chromium.org/126293

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2215 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
erik.corry@gmail.com 2009-06-18 07:33:44 +00:00
parent cbda639253
commit 5f77401b0c
1 changed files with 32 additions and 1 deletions
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33
src/ia32/codegen-ia32.cc
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@ -1387,7 +1387,11 @@ class DeferredInlineSmiOperation: public DeferredCode {
void DeferredInlineSmiOperation::Generate() {
__ push(src_);
__ push(Immediate(value_));
GenericBinaryOpStub stub(op_, overwrite_mode_, SMI_CODE_INLINED);
// For mod we don't generate all the Smi code inline.
GenericBinaryOpStub stub(
op_,
overwrite_mode_,
(op_ == Token::MOD) ? SMI_CODE_IN_STUB : SMI_CODE_INLINED);
__ CallStub(&stub);
if (!dst_.is(eax)) __ mov(dst_, eax);
}
@ -1772,6 +1776,33 @@ void CodeGenerator::ConstantSmiBinaryOperation(Token::Value op,
break;
}
// Generate inline code for mod of powers of 2 and negative powers of 2.
case Token::MOD:
if (!reversed &&
int_value != 0 &&
(IsPowerOf2(int_value) || IsPowerOf2(-int_value))) {
operand->ToRegister();
frame_->Spill(operand->reg());
DeferredCode* deferred = new DeferredInlineSmiOperation(op,
operand->reg(),
operand->reg(),
smi_value,
overwrite_mode);
// Check for negative or non-Smi left hand side.
__ test(operand->reg(), Immediate(kSmiTagMask | 0x80000000));
deferred->Branch(not_zero);
if (int_value < 0) int_value = -int_value;
if (int_value == 1) {
__ mov(operand->reg(), Immediate(Smi::FromInt(0)));
} else {
__ and_(operand->reg(), (int_value << kSmiTagSize) - 1);
}
deferred->BindExit();
frame_->Push(operand);
break;
}
// Fall through if we did not find a power of 2 on the right hand side!
default: {
Result constant_operand(value);
if (reversed) {