Reviewers: Vyacheslav Egorov,
Description:
Slightly improved register assignment for %_IsObject on IA32 and ARM.
The new approach uses one temp register instead of two on IA32. The ARM
instructions are modified so the input can be UseAtStart again.
Please review this at http://codereview.chromium.org/7274025/
SVN Base: http://v8.googlecode.com/svn/branches/bleeding_edge/
Affected files:
M src/arm/lithium-arm.h
M src/arm/lithium-arm.cc
M src/arm/lithium-codegen-arm.h
M src/arm/lithium-codegen-arm.cc
M src/ia32/lithium-codegen-ia32.h
M src/ia32/lithium-codegen-ia32.cc
M src/ia32/lithium-ia32.h
M src/ia32/lithium-ia32.cc
Index: src/arm/lithium-arm.cc
===================================================================
--- src/arm/lithium-arm.cc (revision 8444)
+++ src/arm/lithium-arm.cc (working copy)
@@ -1098,7 +1098,7 @@
HIsObject* compare = HIsObject::cast(v);
ASSERT(compare->value()->representation().IsTagged());
LOperand* temp = TempRegister();
- return new LIsObjectAndBranch(UseRegister(compare->value()), temp);
+ return new LIsObjectAndBranch(UseRegisterAtStart(compare->value()),
temp);
} else if (v->IsCompareObjectEq()) {
HCompareObjectEq* compare = HCompareObjectEq::cast(v);
return new LCmpObjectEqAndBranch(UseRegisterAtStart(compare->left()),
Index: src/arm/lithium-arm.h
===================================================================
--- src/arm/lithium-arm.h (revision 8444)
+++ src/arm/lithium-arm.h (working copy)
@@ -705,7 +705,7 @@
};
-class LIsObject: public LTemplateInstruction<1, 1, 1> {
+class LIsObject: public LTemplateInstruction<1, 1, 0> {
public:
explicit LIsObject(LOperand* value) {
inputs_[0] = value;
@@ -715,7 +715,7 @@
};
-class LIsObjectAndBranch: public LControlInstruction<1, 2> {
+class LIsObjectAndBranch: public LControlInstruction<1, 1> {
public:
LIsObjectAndBranch(LOperand* value, LOperand* temp) {
inputs_[0] = value;
Index: src/arm/lithium-codegen-arm.cc
===================================================================
--- src/arm/lithium-codegen-arm.cc (revision 8444)
+++ src/arm/lithium-codegen-arm.cc (working copy)
@@ -1796,13 +1796,13 @@
Condition LCodeGen::EmitIsObject(Register input,
Register temp1,
- Register temp2,
Label* is_not_object,
Label* is_object) {
+ Register temp2 = scratch0();
__ JumpIfSmi(input, is_not_object);
- __ LoadRoot(temp1, Heap::kNullValueRootIndex);
- __ cmp(input, temp1);
+ __ LoadRoot(temp2, Heap::kNullValueRootIndex);
+ __ cmp(input, temp2);
__ b(eq, is_object);
// Load map.
@@ -1824,10 +1824,9 @@
void LCodeGen::DoIsObject(LIsObject* instr) {
Register reg = ToRegister(instr->InputAt(0));
Register result = ToRegister(instr->result());
- Register temp = scratch0();
Label is_false, is_true, done;
- Condition true_cond = EmitIsObject(reg, result, temp, &is_false,
&is_true);
+ Condition true_cond = EmitIsObject(reg, result, &is_false, &is_true);
__ b(true_cond, &is_true);
__ bind(&is_false);
@@ -1852,7 +1851,7 @@
Label* false_label = chunk_->GetAssemblyLabel(false_block);
Condition true_cond =
- EmitIsObject(reg, temp1, temp2, false_label, true_label);
+ EmitIsObject(reg, temp1, false_label, true_label);
EmitBranch(true_block, false_block, true_cond);
}
Index: src/arm/lithium-codegen-arm.h
===================================================================
--- src/arm/lithium-codegen-arm.h (revision 8444)
+++ src/arm/lithium-codegen-arm.h (working copy)
@@ -280,7 +280,6 @@
// true and false label should be made, to optimize fallthrough.
Condition EmitIsObject(Register input,
Register temp1,
- Register temp2,
Label* is_not_object,
Label* is_object);
Index: src/ia32/lithium-codegen-ia32.cc
===================================================================
--- src/ia32/lithium-codegen-ia32.cc (revision 8444)
+++ src/ia32/lithium-codegen-ia32.cc (working copy)
@@ -1637,13 +1637,8 @@
Condition LCodeGen::EmitIsObject(Register input,
Register temp1,
- Register temp2,
Label* is_not_object,
Label* is_object) {
- ASSERT(!input.is(temp1));
- ASSERT(!input.is(temp2));
- ASSERT(!temp1.is(temp2));
-
__ JumpIfSmi(input, is_not_object);
__ cmp(input, isolate()->factory()->null_value());
@@ -1651,14 +1646,14 @@
__ mov(temp1, FieldOperand(input, HeapObject::kMapOffset));
// Undetectable objects behave like undefined.
- __ movzx_b(temp2, FieldOperand(temp1, Map::kBitFieldOffset));
- __ test(temp2, Immediate(1 << Map::kIsUndetectable));
+ __ test_b(FieldOperand(temp1, Map::kBitFieldOffset),
+ 1 << Map::kIsUndetectable);
__ j(not_zero, is_not_object);
- __ movzx_b(temp2, FieldOperand(temp1, Map::kInstanceTypeOffset));
- __ cmp(temp2, FIRST_NONCALLABLE_SPEC_OBJECT_TYPE);
+ __ movzx_b(temp1, FieldOperand(temp1, Map::kInstanceTypeOffset));
+ __ cmp(temp1, FIRST_NONCALLABLE_SPEC_OBJECT_TYPE);
__ j(below, is_not_object);
- __ cmp(temp2, LAST_NONCALLABLE_SPEC_OBJECT_TYPE);
+ __ cmp(temp1, LAST_NONCALLABLE_SPEC_OBJECT_TYPE);
return below_equal;
}
@@ -1666,10 +1661,9 @@
void LCodeGen::DoIsObject(LIsObject* instr) {
Register reg = ToRegister(instr->InputAt(0));
Register result = ToRegister(instr->result());
- Register temp = ToRegister(instr->TempAt(0));
Label is_false, is_true, done;
- Condition true_cond = EmitIsObject(reg, result, temp, &is_false,
&is_true);
+ Condition true_cond = EmitIsObject(reg, result, &is_false, &is_true);
__ j(true_cond, &is_true);
__ bind(&is_false);
@@ -1686,14 +1680,13 @@
void LCodeGen::DoIsObjectAndBranch(LIsObjectAndBranch* instr) {
Register reg = ToRegister(instr->InputAt(0));
Register temp = ToRegister(instr->TempAt(0));
- Register temp2 = ToRegister(instr->TempAt(1));
int true_block = chunk_->LookupDestination(instr->true_block_id());
int false_block = chunk_->LookupDestination(instr->false_block_id());
Label* true_label = chunk_->GetAssemblyLabel(true_block);
Label* false_label = chunk_->GetAssemblyLabel(false_block);
- Condition true_cond = EmitIsObject(reg, temp, temp2, false_label,
true_label);
+ Condition true_cond = EmitIsObject(reg, temp, false_label, true_label);
EmitBranch(true_block, false_block, true_cond);
}
Index: src/ia32/lithium-codegen-ia32.h
===================================================================
--- src/ia32/lithium-codegen-ia32.h (revision 8444)
+++ src/ia32/lithium-codegen-ia32.h (working copy)
@@ -277,7 +277,6 @@
// true and false label should be made, to optimize fallthrough.
Condition EmitIsObject(Register input,
Register temp1,
- Register temp2,
Label* is_not_object,
Label* is_object);
Index: src/ia32/lithium-ia32.cc
===================================================================
--- src/ia32/lithium-ia32.cc (revision 8444)
+++ src/ia32/lithium-ia32.cc (working copy)
@@ -1096,11 +1096,8 @@
} else if (v->IsIsObject()) {
HIsObject* compare = HIsObject::cast(v);
ASSERT(compare->value()->representation().IsTagged());
- LOperand* temp1 = TempRegister();
- LOperand* temp2 = TempRegister();
- return new LIsObjectAndBranch(UseRegister(compare->value()),
- temp1,
- temp2);
+ LOperand* temp = TempRegister();
+ return new LIsObjectAndBranch(UseRegister(compare->value()), temp);
} else if (v->IsCompareObjectEq()) {
HCompareObjectEq* compare = HCompareObjectEq::cast(v);
return new LCmpObjectEqAndBranch(UseRegisterAtStart(compare->left()),
@@ -1546,7 +1543,7 @@
ASSERT(instr->value()->representation().IsTagged());
LOperand* value = UseRegister(instr->value());
- return DefineAsRegister(new LIsObject(value, TempRegister()));
+ return DefineAsRegister(new LIsObject(value));
}
Index: src/ia32/lithium-ia32.h
===================================================================
--- src/ia32/lithium-ia32.h (revision 8444)
+++ src/ia32/lithium-ia32.h (working copy)
@@ -692,23 +692,21 @@
};
-class LIsObject: public LTemplateInstruction<1, 1, 1> {
+class LIsObject: public LTemplateInstruction<1, 1, 0> {
public:
- LIsObject(LOperand* value, LOperand* temp) {
+ explicit LIsObject(LOperand* value) {
inputs_[0] = value;
- temps_[0] = temp;
}
DECLARE_CONCRETE_INSTRUCTION(IsObject, "is-object")
};
-class LIsObjectAndBranch: public LControlInstruction<1, 2> {
+class LIsObjectAndBranch: public LControlInstruction<1, 1> {
public:
- LIsObjectAndBranch(LOperand* value, LOperand* temp, LOperand* temp2) {
+ LIsObjectAndBranch(LOperand* value, LOperand* temp) {
inputs_[0] = value;
temps_[0] = temp;
- temps_[1] = temp2;
}
DECLARE_CONCRETE_INSTRUCTION(IsObjectAndBranch, "is-object-and-branch")
--
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