Reviewers: William Hesse,
Message:
Small review.
Description:
X64: Added inline conversion of double to smi for LikelySmiBinaryOp shifts.
Please review this at http://codereview.chromium.org/2078028/show
Affected files:
M src/x64/codegen-x64.cc
Index: src/x64/codegen-x64.cc
diff --git a/src/x64/codegen-x64.cc b/src/x64/codegen-x64.cc
index
50e5aa110e7e82ecea528ff8330f2df786ca272c..bf2aa876700d204517c663adc0cda55d8bf1c042
100644
--- a/src/x64/codegen-x64.cc
+++ b/src/x64/codegen-x64.cc
@@ -7018,7 +7018,43 @@ Result
CodeGenerator::LikelySmiBinaryOperation(BinaryOperation* expr,
left->reg(),
rcx,
overwrite_mode);
- __ JumpIfNotBothSmi(left->reg(), rcx, deferred->entry_label());
+
+ Label do_op;
+ if (right_type_info.IsSmi()) {
+ if (FLAG_debug_code) {
+ __ AbortIfNotSmi(right->reg());
+ }
+ __ movq(answer.reg(), left->reg());
+ // If left is not known to be a smi, check if it is.
+ // If left is not known to be a number, and it isn't a smi, check if
+ // it is a HeapNumber.
+ if (!left_type_info.IsSmi()) {
+ __ JumpIfSmi(answer.reg(), &do_op);
+ if (!left_type_info.IsNumber()) {
+ // Branch if not a heapnumber.
+ __ Cmp(FieldOperand(answer.reg(), HeapObject::kMapOffset),
+ Factory::heap_number_map());
+ deferred->Branch(not_equal);
+ }
+ // Load integer value into answer register using truncation.
+ __ cvttsd2si(answer.reg(),
+ FieldOperand(answer.reg(), HeapNumber::kValueOffset));
+ // Branch if we might have overflowed.
+ // (False negative for Smi::kMinValue)
+ __ cmpq(answer.reg(), Immediate(0x80000000));
+ deferred->Branch(equal);
+ // TODO(lrn): Inline shifts on int32 here instead of first
smi-tagging.
+ __ Integer32ToSmi(answer.reg(), answer.reg());
+ } else {
+ // Fast case - both are actually smis.
+ if (FLAG_debug_code) {
+ __ AbortIfNotSmi(left->reg());
+ }
+ }
+ } else {
+ __ JumpIfNotBothSmi(left->reg(), rcx, deferred->entry_label());
+ }
+ __ bind(&do_op);
// Perform the operation.
switch (op) {
--
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