Revision: 8758
Author: [email protected]
Date: Thu Jul 28 06:33:51 2011
Log: Use type info for the ToBoolean translation in crankshaft.
To do this, the Branch instruction needs to carry around a temporary
register,
but only when the crankshafted code will make a map access. When the
crankshafted code sees an object of a type it hasn't encountered before, it
will
always trigger a deopt. Another option in theses cases would be calling a
ToBooleanStub which can handle all types, but then one has to be careful to
*not* trigger a GC (which is currently a bit tricky to achieve).
Const-corrected ToBoolean::Types. Moved the NeedsMap logic into
ToBoolean::Types
itself, where it belongs.
This patch improves a lot of benchmarks, crypto-orig even by 16.7%, but
slows
down others. The slowdown has to be investigated, but I'd like to get this
patch
out first to fix the flakiness problems we currently have due to the
previous
crankshafted ToBoolean.
Review URL: http://codereview.chromium.org/7461107
http://code.google.com/p/v8/source/detail?r=8758
Modified:
/branches/bleeding_edge/src/code-stubs.cc
/branches/bleeding_edge/src/code-stubs.h
/branches/bleeding_edge/src/ia32/code-stubs-ia32.cc
/branches/bleeding_edge/src/ia32/lithium-codegen-ia32.cc
/branches/bleeding_edge/src/ia32/lithium-ia32.cc
/branches/bleeding_edge/src/ia32/lithium-ia32.h
=======================================
--- /branches/bleeding_edge/src/code-stubs.cc Fri Jul 22 05:42:40 2011
+++ /branches/bleeding_edge/src/code-stubs.cc Thu Jul 28 06:33:51 2011
@@ -336,7 +336,7 @@
}
-void ToBooleanStub::Types::Print(StringStream* stream) {
+void ToBooleanStub::Types::Print(StringStream* stream) const {
if (IsEmpty()) stream->Add("None");
if (Contains(UNDEFINED)) stream->Add("Undefined");
if (Contains(BOOLEAN)) stream->Add("Bool");
@@ -349,7 +349,7 @@
}
-void ToBooleanStub::Types::TraceTransition(Types to) {
+void ToBooleanStub::Types::TraceTransition(Types to) const {
if (!FLAG_trace_ic) return;
char buffer[100];
NoAllocationStringAllocator allocator(buffer,
@@ -393,6 +393,14 @@
return !object->IsUndetectableObject();
}
}
+
+
+bool ToBooleanStub::Types::NeedsMap() const {
+ return Contains(ToBooleanStub::SPEC_OBJECT)
+ || Contains(ToBooleanStub::STRING)
+ || Contains(ToBooleanStub::HEAP_NUMBER)
+ || Contains(ToBooleanStub::INTERNAL_OBJECT);
+}
} } // namespace v8::internal
=======================================
--- /branches/bleeding_edge/src/code-stubs.h Wed Jul 27 07:56:36 2011
+++ /branches/bleeding_edge/src/code-stubs.h Thu Jul 28 06:33:51 2011
@@ -926,9 +926,10 @@
bool Contains(Type type) const { return set_.Contains(type); }
void Add(Type type) { set_.Add(type); }
byte ToByte() const { return set_.ToIntegral(); }
- void Print(StringStream* stream);
- void TraceTransition(Types to);
+ void Print(StringStream* stream) const;
+ void TraceTransition(Types to) const;
bool Record(Handle<Object> object);
+ bool NeedsMap() const;
private:
EnumSet<Type, byte> set_;
=======================================
--- /branches/bleeding_edge/src/ia32/code-stubs-ia32.cc Wed Jul 27 07:56:36
2011
+++ /branches/bleeding_edge/src/ia32/code-stubs-ia32.cc Thu Jul 28 06:33:51
2011
@@ -258,12 +258,6 @@
// 'null' -> false.
CheckOddball(masm, NULL_TYPE, factory->null_value(), false, &patch);
- bool need_map =
- types_.Contains(SPEC_OBJECT) |
- types_.Contains(STRING) |
- types_.Contains(HEAP_NUMBER) |
- types_.Contains(INTERNAL_OBJECT);
-
if (types_.Contains(SMI)) {
// Smis: 0 -> false, all other -> true
Label not_smi;
@@ -274,12 +268,12 @@
}
__ ret(1 * kPointerSize);
__ bind(¬_smi);
- } else if (need_map) {
+ } else if (types_.NeedsMap()) {
// If we need a map later and have a Smi -> patch.
__ JumpIfSmi(argument, &patch, Label::kNear);
}
- if (need_map) {
+ if (types_.NeedsMap()) {
__ mov(map, FieldOperand(argument, HeapObject::kMapOffset));
// Everything with a map could be undetectable, so check this now.
=======================================
--- /branches/bleeding_edge/src/ia32/lithium-codegen-ia32.cc Wed Jul 27
07:56:36 2011
+++ /branches/bleeding_edge/src/ia32/lithium-codegen-ia32.cc Thu Jul 28
06:33:51 2011
@@ -1392,45 +1392,133 @@
EmitBranch(true_block, false_block, not_equal);
} else {
ASSERT(r.IsTagged());
+ Factory* factory = this->factory();
Register reg = ToRegister(instr->InputAt(0));
if (instr->hydrogen()->value()->type().IsBoolean()) {
- __ cmp(reg, factory()->true_value());
+ __ cmp(reg, factory->true_value());
EmitBranch(true_block, false_block, equal);
} else {
Label* true_label = chunk_->GetAssemblyLabel(true_block);
Label* false_label = chunk_->GetAssemblyLabel(false_block);
- __ cmp(reg, factory()->undefined_value());
- __ j(equal, false_label);
- __ cmp(reg, factory()->true_value());
- __ j(equal, true_label);
- __ cmp(reg, factory()->false_value());
- __ j(equal, false_label);
- __ test(reg, Operand(reg));
- __ j(equal, false_label);
- __ JumpIfSmi(reg, true_label);
-
- // Test for double values. Zero is false.
- Label call_stub;
- __ cmp(FieldOperand(reg, HeapObject::kMapOffset),
- factory()->heap_number_map());
- __ j(not_equal, &call_stub, Label::kNear);
- __ fldz();
- __ fld_d(FieldOperand(reg, HeapNumber::kValueOffset));
- __ FCmp();
- __ j(zero, false_label);
- __ jmp(true_label);
-
- // The conversion stub doesn't cause garbage collections so it's
- // safe to not record a safepoint after the call.
- __ bind(&call_stub);
- ToBooleanStub stub(eax, ToBooleanStub::all_types());
- __ pushad();
- __ push(reg);
- __ CallStub(&stub);
- __ test(eax, Operand(eax));
- __ popad();
- EmitBranch(true_block, false_block, not_zero);
+ ToBooleanStub::Types expected =
instr->hydrogen()->expected_input_types();
+ // Avoid deopts in the case where we've never executed this path
before.
+ if (expected.IsEmpty()) expected = ToBooleanStub::all_types();
+
+ if (expected.Contains(ToBooleanStub::UNDEFINED)) {
+ // undefined -> false.
+ __ cmp(reg, factory->undefined_value());
+ __ j(equal, false_label);
+ } else if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+ // We've seen undefined for the first time -> deopt.
+ __ cmp(reg, factory->undefined_value());
+ DeoptimizeIf(equal, instr->environment());
+ }
+
+ if (expected.Contains(ToBooleanStub::BOOLEAN)) {
+ // true -> true.
+ __ cmp(reg, factory->true_value());
+ __ j(equal, true_label);
+ } else if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+ // We've seen a string for the first time -> deopt.
+ __ cmp(reg, factory->true_value());
+ DeoptimizeIf(equal, instr->environment());
+ }
+
+ if (expected.Contains(ToBooleanStub::BOOLEAN)) {
+ // false -> false.
+ __ cmp(reg, factory->false_value());
+ __ j(equal, false_label);
+ } else if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+ // We've seen a string for the first time -> deopt.
+ __ cmp(reg, factory->false_value());
+ DeoptimizeIf(equal, instr->environment());
+ }
+
+ if (expected.Contains(ToBooleanStub::NULL_TYPE)) {
+ // 'null' -> false.
+ __ cmp(reg, factory->null_value());
+ __ j(equal, false_label);
+ } else if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+ // We've seen null for the first time -> deopt.
+ __ cmp(reg, factory->null_value());
+ DeoptimizeIf(equal, instr->environment());
+ }
+
+ if (expected.Contains(ToBooleanStub::SMI)) {
+ // Smis: 0 -> false, all other -> true.
+ __ test(reg, Operand(reg));
+ __ j(equal, false_label);
+ __ JumpIfSmi(reg, true_label);
+ } else if (expected.NeedsMap()) {
+ // If we need a map later and have a Smi -> deopt.
+ __ test(reg, Immediate(kSmiTagMask));
+ DeoptimizeIf(zero, instr->environment());
+ }
+
+ Register map;
+ if (expected.NeedsMap()) {
+ map = ToRegister(instr->TempAt(0));
+ ASSERT(!map.is(reg));
+ __ mov(map, FieldOperand(reg, HeapObject::kMapOffset));
+ // Everything with a map could be undetectable, so check this now.
+ __ test_b(FieldOperand(map, Map::kBitFieldOffset),
+ 1 << Map::kIsUndetectable);
+ // Undetectable -> false.
+ __ j(not_zero, false_label);
+ }
+
+ if (expected.Contains(ToBooleanStub::SPEC_OBJECT)) {
+ // spec object -> true.
+ __ CmpInstanceType(map, FIRST_SPEC_OBJECT_TYPE);
+ __ j(above_equal, true_label);
+ } else if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+ // We've seen a spec object for the first time -> deopt.
+ __ CmpInstanceType(map, FIRST_SPEC_OBJECT_TYPE);
+ DeoptimizeIf(above_equal, instr->environment());
+ }
+
+ if (expected.Contains(ToBooleanStub::STRING)) {
+ // String value -> false iff empty.
+ Label not_string;
+ __ CmpInstanceType(map, FIRST_NONSTRING_TYPE);
+ __ j(above_equal, ¬_string, Label::kNear);
+ __ cmp(FieldOperand(reg, String::kLengthOffset), Immediate(0));
+ __ j(not_zero, true_label);
+ __ jmp(false_label);
+ __ bind(¬_string);
+ } else if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+ // We've seen a string for the first time -> deopt
+ __ CmpInstanceType(map, FIRST_NONSTRING_TYPE);
+ DeoptimizeIf(below, instr->environment());
+ }
+
+ if (expected.Contains(ToBooleanStub::HEAP_NUMBER)) {
+ // heap number -> false iff +0, -0, or NaN.
+ Label not_heap_number;
+ __ cmp(FieldOperand(reg, HeapObject::kMapOffset),
+ factory->heap_number_map());
+ __ j(not_equal, ¬_heap_number, Label::kNear);
+ __ fldz();
+ __ fld_d(FieldOperand(reg, HeapNumber::kValueOffset));
+ __ FCmp();
+ __ j(zero, false_label);
+ __ jmp(true_label);
+ __ bind(¬_heap_number);
+ } else if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+ // We've seen a heap number for the first time -> deopt.
+ __ cmp(FieldOperand(reg, HeapObject::kMapOffset),
+ factory->heap_number_map());
+ DeoptimizeIf(equal, instr->environment());
+ }
+
+ if (expected.Contains(ToBooleanStub::INTERNAL_OBJECT)) {
+ // internal objects -> true
+ __ jmp(true_label);
+ } else {
+ // We've seen something for the first time -> deopt.
+ DeoptimizeIf(no_condition, instr->environment());
+ }
}
}
}
=======================================
--- /branches/bleeding_edge/src/ia32/lithium-ia32.cc Tue Jul 19 06:04:00
2011
+++ /branches/bleeding_edge/src/ia32/lithium-ia32.cc Thu Jul 28 06:33:51
2011
@@ -1041,7 +1041,10 @@
: instr->SecondSuccessor();
return new LGoto(successor->block_id());
}
- return new LBranch(UseRegisterAtStart(v));
+ ToBooleanStub::Types expected = instr->expected_input_types();
+ bool needs_temp = expected.NeedsMap() || expected.IsEmpty();
+ LOperand* temp = needs_temp ? TempRegister() : NULL;
+ return AssignEnvironment(new LBranch(UseRegister(v), temp));
}
=======================================
--- /branches/bleeding_edge/src/ia32/lithium-ia32.h Tue Jul 19 06:04:00 2011
+++ /branches/bleeding_edge/src/ia32/lithium-ia32.h Thu Jul 28 06:33:51 2011
@@ -876,10 +876,11 @@
};
-class LBranch: public LControlInstruction<1, 0> {
+class LBranch: public LControlInstruction<1, 1> {
public:
- explicit LBranch(LOperand* value) {
+ explicit LBranch(LOperand* value, LOperand* temp) {
inputs_[0] = value;
+ temps_[0] = temp;
}
DECLARE_CONCRETE_INSTRUCTION(Branch, "branch")
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