Revision: 22051
Author: [email protected]
Date: Fri Jun 27 09:00:31 2014 UTC
Log: ARM64: avoid duplicate load of double constants
[email protected], [email protected]
BUG=
Review URL: https://codereview.chromium.org/357973002
http://code.google.com/p/v8/source/detail?r=22051
Modified:
/branches/bleeding_edge/src/arm64/lithium-arm64.cc
/branches/bleeding_edge/src/arm64/lithium-codegen-arm64.cc
=======================================
--- /branches/bleeding_edge/src/arm64/lithium-arm64.cc Thu Jun 26 10:00:36
2014 UTC
+++ /branches/bleeding_edge/src/arm64/lithium-arm64.cc Fri Jun 27 09:00:31
2014 UTC
@@ -1274,15 +1274,13 @@
ASSERT(r.IsDouble());
ASSERT(instr->left()->representation().IsDouble());
ASSERT(instr->right()->representation().IsDouble());
- // TODO(all): In fact the only case that we can handle more
efficiently is
- // when one of the operand is the constant 0. Currently the
MacroAssembler
- // will be able to cope with any constant by loading it into an
internal
- // scratch register. This means that if the constant is used more that
once,
- // it will be loaded multiple times. Unfortunatly crankshaft already
- // duplicates constant loads, but we should modify the code below once
this
- // issue has been addressed in crankshaft.
- LOperand* left = UseRegisterOrConstantAtStart(instr->left());
- LOperand* right = UseRegisterOrConstantAtStart(instr->right());
+ if (instr->left()->IsConstant() && instr->right()->IsConstant()) {
+ LOperand* left = UseConstant(instr->left());
+ LOperand* right = UseConstant(instr->right());
+ return new(zone()) LCompareNumericAndBranch(left, right);
+ }
+ LOperand* left = UseRegisterAtStart(instr->left());
+ LOperand* right = UseRegisterAtStart(instr->right());
return new(zone()) LCompareNumericAndBranch(left, right);
}
}
=======================================
--- /branches/bleeding_edge/src/arm64/lithium-codegen-arm64.cc Thu Jun 26
10:00:36 2014 UTC
+++ /branches/bleeding_edge/src/arm64/lithium-codegen-arm64.cc Fri Jun 27
09:00:31 2014 UTC
@@ -2484,17 +2484,7 @@
EmitGoto(next_block);
} else {
if (instr->is_double()) {
- if (right->IsConstantOperand()) {
- __ Fcmp(ToDoubleRegister(left),
- ToDouble(LConstantOperand::cast(right)));
- } else if (left->IsConstantOperand()) {
- // Commute the operands and the condition.
- __ Fcmp(ToDoubleRegister(right),
- ToDouble(LConstantOperand::cast(left)));
- cond = CommuteCondition(cond);
- } else {
- __ Fcmp(ToDoubleRegister(left), ToDoubleRegister(right));
- }
+ __ Fcmp(ToDoubleRegister(left), ToDoubleRegister(right));
// If a NaN is involved, i.e. the result is unordered (V set),
// jump to false block label.
--
--
v8-dev mailing list
[email protected]
http://groups.google.com/group/v8-dev
---
You received this message because you are subscribed to the Google Groups "v8-dev" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to [email protected].
For more options, visit https://groups.google.com/d/optout.
