Index: src/ia32/lithium-codegen-ia32.cc |
=================================================================== |
--- src/ia32/lithium-codegen-ia32.cc (revision 9243) |
+++ src/ia32/lithium-codegen-ia32.cc (working copy) |
@@ -317,6 +317,12 @@ |
} |
+double LCodeGen::ToDouble(LConstantOperand* op) const { |
+ Handle<Object> value = chunk_->LookupLiteral(op); |
+ return value->Number(); |
+} |
+ |
+ |
Immediate LCodeGen::ToImmediate(LOperand* op) { |
LConstantOperand* const_op = LConstantOperand::cast(op); |
Handle<Object> literal = chunk_->LookupLiteral(const_op); |
@@ -1527,32 +1533,40 @@ |
} |
-void LCodeGen::EmitCmpI(LOperand* left, LOperand* right) { |
- if (right->IsConstantOperand()) { |
- __ cmp(ToOperand(left), ToImmediate(right)); |
- } else { |
- __ cmp(ToRegister(left), ToOperand(right)); |
- } |
-} |
- |
- |
void LCodeGen::DoCmpIDAndBranch(LCmpIDAndBranch* instr) { |
LOperand* left = instr->InputAt(0); |
LOperand* right = instr->InputAt(1); |
int false_block = chunk_->LookupDestination(instr->false_block_id()); |
int true_block = chunk_->LookupDestination(instr->true_block_id()); |
+ Condition cc = TokenToCondition(instr->op(), instr->is_double()); |
- if (instr->is_double()) { |
- // Don't base result on EFLAGS when a NaN is involved. Instead |
- // jump to the false block. |
- __ ucomisd(ToDoubleRegister(left), ToDoubleRegister(right)); |
- __ j(parity_even, chunk_->GetAssemblyLabel(false_block)); |
+ if (left->IsConstantOperand() && right->IsConstantOperand()) { |
+ // We can statically evaluate the comparison. |
+ double left_val = ToDouble(LConstantOperand::cast(left)); |
+ double right_val = ToDouble(LConstantOperand::cast(right)); |
+ int next_block = |
+ EvalComparison(instr->op(), left_val, right_val) ? true_block |
+ : false_block; |
+ EmitGoto(next_block); |
} else { |
- EmitCmpI(left, right); |
+ if (instr->is_double()) { |
+ // Don't base result on EFLAGS when a NaN is involved. Instead |
+ // jump to the false block. |
+ __ ucomisd(ToDoubleRegister(left), ToDoubleRegister(right)); |
+ __ j(parity_even, chunk_->GetAssemblyLabel(false_block)); |
+ } else { |
+ if (right->IsConstantOperand()) { |
+ __ cmp(ToOperand(left), ToImmediate(right)); |
William Hesse
2011/10/20 10:28:40
If the immediate value is 0, this can also be test
Alexandre
2011/10/20 10:59:49
I forgot to change it to tst for Intel.
I intentio
|
+ } else if (left->IsConstantOperand()) { |
+ __ cmp(ToOperand(right), ToImmediate(left)); |
+ // We transposed the operands. Reverse the condition. |
+ cc = ReverseCondition(cc); |
+ } else { |
+ __ cmp(ToRegister(left), ToOperand(right)); |
+ } |
+ } |
+ EmitBranch(true_block, false_block, cc); |
} |
- |
- Condition cc = TokenToCondition(instr->op(), instr->is_double()); |
- EmitBranch(true_block, false_block, cc); |
} |