AuroraMiddleware/v8
1
0
Fork 0
Code Issues 2 Pull Requests Releases Wiki Activity

Fixed deopt reasons in TaggedToI.

Browse Source 
Every DeoptimizeIf should be preceded by a RecordComment explaining
the reason. In the long run, the reason should be an argument of
DeoptimizeIf, but we're not there yet.

On x87, things are a bit ugly due to some pushing/popping, so if
somebody feels inclined to improve this: Feel free. Probably the right
approach would be reloading instead of the push/pop horror.

Another thing is our inconsistent handling of the "done" continuation
of deferred code on the various platforms, I made tiny changes on the
way, but this should better be unified somehow, with all those
micro-optimizations removed.

R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/578583002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@23996 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
svenpanne@chromium.org 2014-09-17 09:51:17 +00:00
parent fdcf5f99b2
commit ac1b9b11dc
13 changed files with 114 additions and 156 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
src/arm/lithium-codegen-arm.cc
View File

@ -4975,16 +4975,17 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
__ bind(&check_false);
__ LoadRoot(ip, Heap::kFalseValueRootIndex);
__ cmp(scratch2, Operand(ip));
__ RecordComment("Deferred TaggedToI: cannot truncate");
DeoptimizeIf(ne, instr->environment());
__ mov(input_reg, Operand::Zero());
__ b(&done);
} else {
// Deoptimize if we don't have a heap number.
__ RecordComment("Deferred TaggedToI: not a heap number");
DeoptimizeIf(ne, instr->environment());
__ sub(ip, scratch2, Operand(kHeapObjectTag));
__ vldr(double_scratch2, ip, HeapNumber::kValueOffset);
__ TryDoubleToInt32Exact(input_reg, double_scratch2, double_scratch);
__ RecordComment("Deferred TaggedToI: lost precision or NaN");
DeoptimizeIf(ne, instr->environment());
if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
@ -4992,6 +4993,7 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
__ b(ne, &done);
__ VmovHigh(scratch1, double_scratch2);
__ tst(scratch1, Operand(HeapNumber::kSignMask));
__ RecordComment("Deferred TaggedToI: minus zero");
DeoptimizeIf(ne, instr->environment());
}
}

5
src/arm64/lithium-codegen-arm64.cc
View File

@ -5645,10 +5645,9 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr,
instr->environment());
} else {
Register output = ToRegister32(instr->result());
DoubleRegister dbl_scratch2 = ToDoubleRegister(temp2);
// Deoptimized if it's not a heap number.
__ RecordComment("Deferred TaggedToI: not a heap number");
DeoptimizeIfNotRoot(scratch1, Heap::kHeapNumberMapRootIndex,
instr->environment());
@ -5656,12 +5655,14 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr,
// function. If the result is out of range, branch to deoptimize.
__ Ldr(dbl_scratch1, FieldMemOperand(input, HeapNumber::kValueOffset));
__ TryRepresentDoubleAsInt32(output, dbl_scratch1, dbl_scratch2);
__ RecordComment("Deferred TaggedToI: lost precision or NaN");
DeoptimizeIf(ne, instr->environment());
if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
__ Cmp(output, 0);
__ B(ne, &done);
__ Fmov(scratch1, dbl_scratch1);
__ RecordComment("Deferred TaggedToI: minus zero");
DeoptimizeIfNegative(scratch1, instr->environment());
}
}

31
src/ia32/lithium-codegen-ia32.cc
View File

@ -4764,15 +4764,28 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr, Label* done) {
DeoptimizeIf(not_equal, instr->environment());
__ Move(input_reg, Immediate(0));
} else {
Label bailout;
XMMRegister scratch = (instr->temp() != NULL)
? ToDoubleRegister(instr->temp())
: no_xmm_reg;
__ TaggedToI(input_reg, input_reg, scratch,
instr->hydrogen()->GetMinusZeroMode(), &bailout);
__ jmp(done);
__ bind(&bailout);
DeoptimizeIf(no_condition, instr->environment());
XMMRegister scratch = ToDoubleRegister(instr->temp());
DCHECK(!scratch.is(xmm0));
__ cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
isolate()->factory()->heap_number_map());
__ RecordComment("Deferred TaggedToI: not a heap number");
DeoptimizeIf(not_equal, instr->environment());
__ movsd(xmm0, FieldOperand(input_reg, HeapNumber::kValueOffset));
__ cvttsd2si(input_reg, Operand(xmm0));
__ Cvtsi2sd(scratch, Operand(input_reg));
__ ucomisd(xmm0, scratch);
__ RecordComment("Deferred TaggedToI: lost precision");
DeoptimizeIf(not_equal, instr->environment());
__ RecordComment("Deferred TaggedToI: NaN");
DeoptimizeIf(parity_even, instr->environment());
if (instr->hydrogen()->GetMinusZeroMode() == FAIL_ON_MINUS_ZERO) {
__ test(input_reg, Operand(input_reg));
__ j(not_zero, done);
__ movmskpd(input_reg, xmm0);
__ and_(input_reg, 1);
__ RecordComment("Deferred TaggedToI: minus zero");
DeoptimizeIf(not_zero, instr->environment());
}
}
}

34
src/ia32/macro-assembler-ia32.cc
View File

@ -346,40 +346,6 @@ void MacroAssembler::TruncateHeapNumberToI(Register result_reg,
}
void MacroAssembler::TaggedToI(Register result_reg,
Register input_reg,
XMMRegister temp,
MinusZeroMode minus_zero_mode,
Label* lost_precision) {
Label done;
DCHECK(!temp.is(xmm0));
cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
isolate()->factory()->heap_number_map());
j(not_equal, lost_precision, Label::kNear);
DCHECK(!temp.is(no_xmm_reg));
movsd(xmm0, FieldOperand(input_reg, HeapNumber::kValueOffset));
cvttsd2si(result_reg, Operand(xmm0));
Cvtsi2sd(temp, Operand(result_reg));
ucomisd(xmm0, temp);
RecordComment("Deferred TaggedToI: lost precision");
j(not_equal, lost_precision, Label::kNear);
RecordComment("Deferred TaggedToI: NaN");
j(parity_even, lost_precision, Label::kNear);
if (minus_zero_mode == FAIL_ON_MINUS_ZERO) {
test(result_reg, Operand(result_reg));
j(not_zero, &done, Label::kNear);
movmskpd(result_reg, xmm0);
and_(result_reg, 1);
RecordComment("Deferred TaggedToI: minus zero");
j(not_zero, lost_precision, Label::kNear);
}
bind(&done);
}
void MacroAssembler::LoadUint32(XMMRegister dst,
Register src) {
Label done;

3
src/ia32/macro-assembler-ia32.h
View File

@ -466,9 +466,6 @@ class MacroAssembler: public Assembler {
XMMRegister scratch, MinusZeroMode minus_zero_mode,
Label* conversion_failed, Label::Distance dst = Label::kFar);
void TaggedToI(Register result_reg, Register input_reg, XMMRegister temp,
MinusZeroMode minus_zero_mode, Label* lost_precision);
// Smi tagging support.
void SmiTag(Register reg) {
STATIC_ASSERT(kSmiTag == 0);

6
src/mips/lithium-codegen-mips.cc
View File

@ -4934,11 +4934,12 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
__ bind(&check_false);
__ LoadRoot(at, Heap::kFalseValueRootIndex);
__ RecordComment("Deferred TaggedToI: cannot truncate");
DeoptimizeIf(ne, instr->environment(), scratch2, Operand(at));
__ Branch(USE_DELAY_SLOT, &done);
__ mov(input_reg, zero_reg); // In delay slot.
} else {
// Deoptimize if we don't have a heap number.
__ RecordComment("Deferred TaggedToI: not a heap number");
DeoptimizeIf(ne, instr->environment(), scratch1, Operand(at));
// Load the double value.
@ -4954,7 +4955,7 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
except_flag,
kCheckForInexactConversion);
// Deopt if the operation did not succeed.
__ RecordComment("Deferred TaggedToI: lost precision or NaN");
DeoptimizeIf(ne, instr->environment(), except_flag, Operand(zero_reg));
if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
@ -4962,6 +4963,7 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
__ Mfhc1(scratch1, double_scratch);
__ And(scratch1, scratch1, Operand(HeapNumber::kSignMask));
__ RecordComment("Deferred TaggedToI: minus zero");
DeoptimizeIf(ne, instr->environment(), scratch1, Operand(zero_reg));
}
}

6
src/mips64/lithium-codegen-mips64.cc
View File

@ -4973,11 +4973,12 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
__ bind(&check_false);
__ LoadRoot(at, Heap::kFalseValueRootIndex);
__ RecordComment("Deferred TaggedToI: cannot truncate");
DeoptimizeIf(ne, instr->environment(), scratch2, Operand(at));
__ Branch(USE_DELAY_SLOT, &done);
__ mov(input_reg, zero_reg); // In delay slot.
} else {
// Deoptimize if we don't have a heap number.
__ RecordComment("Deferred TaggedToI: not a heap number");
DeoptimizeIf(ne, instr->environment(), scratch1, Operand(at));
// Load the double value.
@ -4993,7 +4994,7 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
except_flag,
kCheckForInexactConversion);
// Deopt if the operation did not succeed.
__ RecordComment("Deferred TaggedToI: lost precision or NaN");
DeoptimizeIf(ne, instr->environment(), except_flag, Operand(zero_reg));
if (instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero)) {
@ -5001,6 +5002,7 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr) {
__ mfhc1(scratch1, double_scratch); // Get exponent/sign bits.
__ And(scratch1, scratch1, Operand(HeapNumber::kSignMask));
__ RecordComment("Deferred TaggedToI: minus zero");
DeoptimizeIf(ne, instr->environment(), scratch1, Operand(zero_reg));
}
}

31
src/x64/lithium-codegen-x64.cc
View File

@ -4963,16 +4963,29 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr, Label* done) {
__ RecordComment("Deferred TaggedToI: cannot truncate");
DeoptimizeIf(not_equal, instr->environment());
__ Set(input_reg, 0);
__ jmp(done);
} else {
Label bailout;
XMMRegister xmm_temp = ToDoubleRegister(instr->temp());
__ TaggedToI(input_reg, input_reg, xmm_temp,
instr->hydrogen()->GetMinusZeroMode(), &bailout, Label::kNear);
__ jmp(done);
__ bind(&bailout);
DeoptimizeIf(no_condition, instr->environment());
XMMRegister scratch = ToDoubleRegister(instr->temp());
DCHECK(!scratch.is(xmm0));
__ CompareRoot(FieldOperand(input_reg, HeapObject::kMapOffset),
Heap::kHeapNumberMapRootIndex);
__ RecordComment("Deferred TaggedToI: not a heap number");
DeoptimizeIf(not_equal, instr->environment());
__ movsd(xmm0, FieldOperand(input_reg, HeapNumber::kValueOffset));
__ cvttsd2si(input_reg, xmm0);
__ Cvtlsi2sd(scratch, input_reg);
__ ucomisd(xmm0, scratch);
__ RecordComment("Deferred TaggedToI: lost precision");
DeoptimizeIf(not_equal, instr->environment());
__ RecordComment("Deferred TaggedToI: NaN");
DeoptimizeIf(parity_even, instr->environment());
if (instr->hydrogen()->GetMinusZeroMode() == FAIL_ON_MINUS_ZERO) {
__ testl(input_reg, input_reg);
__ j(not_zero, done);
__ movmskpd(input_reg, xmm0);
__ andl(input_reg, Immediate(1));
__ RecordComment("Deferred TaggedToI: minus zero");
DeoptimizeIf(not_zero, instr->environment());
}
}
}

33
src/x64/macro-assembler-x64.cc
View File

@ -3545,39 +3545,6 @@ void MacroAssembler::DoubleToI(Register result_reg,
}
void MacroAssembler::TaggedToI(Register result_reg,
Register input_reg,
XMMRegister temp,
MinusZeroMode minus_zero_mode,
Label* lost_precision,
Label::Distance dst) {
Label done;
DCHECK(!temp.is(xmm0));
// Heap number map check.
CompareRoot(FieldOperand(input_reg, HeapObject::kMapOffset),
Heap::kHeapNumberMapRootIndex);
j(not_equal, lost_precision, dst);
movsd(xmm0, FieldOperand(input_reg, HeapNumber::kValueOffset));
cvttsd2si(result_reg, xmm0);
Cvtlsi2sd(temp, result_reg);
ucomisd(xmm0, temp);
RecordComment("Deferred TaggedToI: lost precision");
j(not_equal, lost_precision, dst);
RecordComment("Deferred TaggedToI: NaN");
j(parity_even, lost_precision, dst); // NaN.
if (minus_zero_mode == FAIL_ON_MINUS_ZERO) {
testl(result_reg, result_reg);
j(not_zero, &done, Label::kNear);
movmskpd(result_reg, xmm0);
andl(result_reg, Immediate(1));
j(not_zero, lost_precision, dst);
}
bind(&done);
}
void MacroAssembler::LoadInstanceDescriptors(Register map,
Register descriptors) {
movp(descriptors, FieldOperand(map, Map::kDescriptorsOffset));

4
src/x64/macro-assembler-x64.h
View File

@ -1033,10 +1033,6 @@ class MacroAssembler: public Assembler {
XMMRegister scratch, MinusZeroMode minus_zero_mode,
Label* conversion_failed, Label::Distance dst = Label::kFar);
void TaggedToI(Register result_reg, Register input_reg, XMMRegister temp,
MinusZeroMode minus_zero_mode, Label* lost_precision,
Label::Distance dst = Label::kFar);
void LoadUint32(XMMRegister dst, Register src);
void LoadInstanceDescriptors(Register map, Register descriptors);

61
src/x87/lithium-codegen-x87.cc
View File

@ -4730,12 +4730,61 @@ void LCodeGen::DoDeferredTaggedToI(LTaggedToI* instr, Label* done) {
DeoptimizeIf(not_equal, instr->environment());
__ Move(input_reg, Immediate(0));
} else {
Label bailout;
__ TaggedToI(input_reg, input_reg,
instr->hydrogen()->GetMinusZeroMode(), &bailout);
__ jmp(done);
__ bind(&bailout);
DeoptimizeIf(no_condition, instr->environment());
// TODO(olivf) Converting a number on the fpu is actually quite slow. We
// should first try a fast conversion and then bailout to this slow case.
__ cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
isolate()->factory()->heap_number_map());
__ RecordComment("Deferred TaggedToI: not a heap number");
DeoptimizeIf(not_equal, instr->environment());
__ sub(esp, Immediate(kPointerSize));
__ fld_d(FieldOperand(input_reg, HeapNumber::kValueOffset));
if (instr->hydrogen()->GetMinusZeroMode() == FAIL_ON_MINUS_ZERO) {
Label no_precision_lost, not_nan, zero_check;
__ fld(0);
__ fist_s(MemOperand(esp, 0));
__ fild_s(MemOperand(esp, 0));
__ FCmp();
__ pop(input_reg);
__ j(equal, &no_precision_lost, Label::kNear);
__ fstp(0);
__ RecordComment("Deferred TaggedToI: lost precision");
DeoptimizeIf(no_condition, instr->environment());
__ bind(&no_precision_lost);
__ j(parity_odd, &not_nan);
__ fstp(0);
__ RecordComment("Deferred TaggedToI: NaN");
DeoptimizeIf(no_condition, instr->environment());
__ bind(&not_nan);
__ test(input_reg, Operand(input_reg));
__ j(zero, &zero_check, Label::kNear);
__ fstp(0);
__ jmp(done);
__ bind(&zero_check);
// To check for minus zero, we load the value again as float, and check
// if that is still 0.
__ sub(esp, Immediate(kPointerSize));
__ fstp_s(Operand(esp, 0));
__ pop(input_reg);
__ test(input_reg, Operand(input_reg));
__ RecordComment("Deferred TaggedToI: minus zero");
DeoptimizeIf(not_zero, instr->environment());
} else {
__ fist_s(MemOperand(esp, 0));
__ fild_s(MemOperand(esp, 0));
__ FCmp();
__ pop(input_reg);
__ RecordComment("Deferred TaggedToI: lost precision");
DeoptimizeIf(not_equal, instr->environment());
__ RecordComment("Deferred TaggedToI: NaN");
DeoptimizeIf(parity_even, instr->environment());
}
}
}

47
src/x87/macro-assembler-x87.cc
View File

@ -254,53 +254,6 @@ void MacroAssembler::TruncateHeapNumberToI(Register result_reg,
}
void MacroAssembler::TaggedToI(Register result_reg,
Register input_reg,
MinusZeroMode minus_zero_mode,
Label* lost_precision) {
Label done;
cmp(FieldOperand(input_reg, HeapObject::kMapOffset),
isolate()->factory()->heap_number_map());
j(not_equal, lost_precision, Label::kNear);
// TODO(olivf) Converting a number on the fpu is actually quite slow. We
// should first try a fast conversion and then bailout to this slow case.
Label lost_precision_pop, zero_check;
Label* lost_precision_int = (minus_zero_mode == FAIL_ON_MINUS_ZERO)
? &lost_precision_pop : lost_precision;
sub(esp, Immediate(kPointerSize));
fld_d(FieldOperand(input_reg, HeapNumber::kValueOffset));
if (minus_zero_mode == FAIL_ON_MINUS_ZERO) fld(0);
fist_s(MemOperand(esp, 0));
fild_s(MemOperand(esp, 0));
FCmp();
pop(result_reg);
j(not_equal, lost_precision_int, Label::kNear);
j(parity_even, lost_precision_int, Label::kNear); // NaN.
if (minus_zero_mode == FAIL_ON_MINUS_ZERO) {
test(result_reg, Operand(result_reg));
j(zero, &zero_check, Label::kNear);
fstp(0);
jmp(&done, Label::kNear);
bind(&zero_check);
// To check for minus zero, we load the value again as float, and check
// if that is still 0.
sub(esp, Immediate(kPointerSize));
fstp_s(Operand(esp, 0));
pop(result_reg);
test(result_reg, Operand(result_reg));
j(zero, &done, Label::kNear);
jmp(lost_precision, Label::kNear);
bind(&lost_precision_pop);
fstp(0);
jmp(lost_precision, Label::kNear);
}
bind(&done);
}
void MacroAssembler::LoadUint32NoSSE2(Register src) {
Label done;
push(src);

3
src/x87/macro-assembler-x87.h
View File

@ -447,9 +447,6 @@ class MacroAssembler: public Assembler {
void X87TOSToI(Register result_reg, MinusZeroMode minus_zero_mode,
Label* conversion_failed, Label::Distance dst = Label::kFar);
void TaggedToI(Register result_reg, Register input_reg,
MinusZeroMode minus_zero_mode, Label* lost_precision);
// Smi tagging support.
void SmiTag(Register reg) {
STATIC_ASSERT(kSmiTag == 0);