Reviewers: danno, Paul Lind, kisg,
Description:
MIPS: Optimize Crankshaft array literal initialization from boilerplate.
Port r10138 (730f5a7f)
Original commit message:
BUG=
TEST=
Please review this at http://codereview.chromium.org/8789012/
Affected files:
M src/mips/lithium-codegen-mips.cc
Index: src/mips/lithium-codegen-mips.cc
diff --git a/src/mips/lithium-codegen-mips.cc
b/src/mips/lithium-codegen-mips.cc
index
0af1f50a8e6498de99f5f5d8f0ca735e12a453e5..a4015b544c238bb4e3d6776b06d567d2cdcee409
100644
--- a/src/mips/lithium-codegen-mips.cc
+++ b/src/mips/lithium-codegen-mips.cc
@@ -4140,15 +4140,32 @@ void
LCodeGen::DoCheckPrototypeMaps(LCheckPrototypeMaps* instr) {
void LCodeGen::DoArrayLiteral(LArrayLiteral* instr) {
- Handle<FixedArray> constant_elements =
instr->hydrogen()->constant_elements();
- ASSERT_EQ(2, constant_elements->length());
- ElementsKind constant_elements_kind =
-
static_cast<ElementsKind>(Smi::cast(constant_elements->get(0))->value());
-
+ Heap* heap = isolate()->heap();
+ ElementsKind boilerplate_elements_kind =
+ instr->hydrogen()->boilerplate_elements_kind();
+
+ // Deopt if the array literal boilerplate ElementsKind is of a type
different
+ // than the expected one. The check isn't necessary if the boilerplate
has
+ // already been converted to FAST_ELEMENTS.
+ if (boilerplate_elements_kind != FAST_ELEMENTS) {
+ LoadHeapObject(a1, instr->hydrogen()->boilerplate_object());
+ // Load map into a2.
+ __ lw(a2, FieldMemOperand(a1, HeapObject::kMapOffset));
+ // Load the map's "bit field 2".
+ __ lbu(a2, FieldMemOperand(a2, Map::kBitField2Offset));
+ // Retrieve elements_kind from bit field 2.
+ __ Ext(a2, a2, Map::kElementsKindShift, Map::kElementsKindBitCount);
+ DeoptimizeIf(ne,
+ instr->environment(),
+ a2,
+ Operand(boilerplate_elements_kind));
+ }
__ lw(a3, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
__ lw(a3, FieldMemOperand(a3, JSFunction::kLiteralsOffset));
__ li(a2, Operand(Smi::FromInt(instr->hydrogen()->literal_index())));
- __ li(a1, Operand(constant_elements));
+ // Boilerplate already exists, constant elements are never accessed.
+ // Pass an empty fixed array.
+ __ li(a1, Operand(Handle<FixedArray>(heap->empty_fixed_array())));
__ Push(a3, a2, a1);
// Pick the right runtime function or stub to call.
@@ -4165,9 +4182,9 @@ void LCodeGen::DoArrayLiteral(LArrayLiteral* instr) {
CallRuntime(Runtime::kCreateArrayLiteralShallow, 3, instr);
} else {
FastCloneShallowArrayStub::Mode mode =
- constant_elements_kind == FAST_DOUBLE_ELEMENTS
- ? FastCloneShallowArrayStub::CLONE_DOUBLE_ELEMENTS
- : FastCloneShallowArrayStub::CLONE_ELEMENTS;
+ boilerplate_elements_kind == FAST_DOUBLE_ELEMENTS
+ ? FastCloneShallowArrayStub::CLONE_DOUBLE_ELEMENTS
+ : FastCloneShallowArrayStub::CLONE_ELEMENTS;
FastCloneShallowArrayStub stub(mode, length);
CallCode(stub.GetCode(), RelocInfo::CODE_TARGET, instr);
}
--
v8-dev mailing list
[email protected]
http://groups.google.com/group/v8-dev
