Introduce ABS as HIR nodes.
NOTE: step 1 of 2 for
"Introduce MIN/MAX/ABS as HIR nodes."
Rationale:
Having explicit MIN/MAX/ABS operations (in contrast
with intrinsics) simplifies recognition and optimization
of these common operations (e.g. constant folding, hoisting,
detection of saturation arithmetic). Furthermore, mapping
conditionals, selectors, intrinsics, etc. (some still TBD)
onto these operations generalizes the way they are optimized
downstream substantially.
Bug: b/65164101
Test: test-art-host,target
Change-Id: I9c93987197216158ba02c8aca2385086adedabc4
diff --git a/compiler/optimizing/code_generator_x86.cc b/compiler/optimizing/code_generator_x86.cc
index 6bf0458..51b96be 100644
--- a/compiler/optimizing/code_generator_x86.cc
+++ b/compiler/optimizing/code_generator_x86.cc
@@ -3802,6 +3802,96 @@
}
}
+void LocationsBuilderX86::VisitAbs(HAbs* abs) {
+ LocationSummary* locations = new (GetGraph()->GetAllocator()) LocationSummary(abs);
+ switch (abs->GetResultType()) {
+ case DataType::Type::kInt32:
+ locations->SetInAt(0, Location::RegisterLocation(EAX));
+ locations->SetOut(Location::SameAsFirstInput());
+ locations->AddTemp(Location::RegisterLocation(EDX));
+ break;
+ case DataType::Type::kInt64:
+ locations->SetInAt(0, Location::RequiresRegister());
+ locations->SetOut(Location::RequiresRegister(), Location::kOutputOverlap);
+ locations->AddTemp(Location::RequiresRegister());
+ break;
+ case DataType::Type::kFloat32:
+ locations->SetInAt(0, Location::RequiresFpuRegister());
+ locations->SetOut(Location::SameAsFirstInput());
+ locations->AddTemp(Location::RequiresFpuRegister());
+ locations->AddTemp(Location::RequiresRegister());
+ break;
+ case DataType::Type::kFloat64:
+ locations->SetInAt(0, Location::RequiresFpuRegister());
+ locations->SetOut(Location::SameAsFirstInput());
+ locations->AddTemp(Location::RequiresFpuRegister());
+ break;
+ default:
+ LOG(FATAL) << "Unexpected type for HAbs " << abs->GetResultType();
+ }
+}
+
+void InstructionCodeGeneratorX86::VisitAbs(HAbs* abs) {
+ LocationSummary* locations = abs->GetLocations();
+ switch (abs->GetResultType()) {
+ case DataType::Type::kInt32: {
+ Register out = locations->Out().AsRegister<Register>();
+ DCHECK_EQ(out, EAX);
+ Register temp = locations->GetTemp(0).AsRegister<Register>();
+ DCHECK_EQ(temp, EDX);
+ // Sign extend EAX into EDX.
+ __ cdq();
+ // XOR EAX with sign.
+ __ xorl(EAX, EDX);
+ // Subtract out sign to correct.
+ __ subl(EAX, EDX);
+ // The result is in EAX.
+ break;
+ }
+ case DataType::Type::kInt64: {
+ Location input = locations->InAt(0);
+ Register input_lo = input.AsRegisterPairLow<Register>();
+ Register input_hi = input.AsRegisterPairHigh<Register>();
+ Location output = locations->Out();
+ Register output_lo = output.AsRegisterPairLow<Register>();
+ Register output_hi = output.AsRegisterPairHigh<Register>();
+ Register temp = locations->GetTemp(0).AsRegister<Register>();
+ // Compute the sign into the temporary.
+ __ movl(temp, input_hi);
+ __ sarl(temp, Immediate(31));
+ // Store the sign into the output.
+ __ movl(output_lo, temp);
+ __ movl(output_hi, temp);
+ // XOR the input to the output.
+ __ xorl(output_lo, input_lo);
+ __ xorl(output_hi, input_hi);
+ // Subtract the sign.
+ __ subl(output_lo, temp);
+ __ sbbl(output_hi, temp);
+ break;
+ }
+ case DataType::Type::kFloat32: {
+ XmmRegister out = locations->Out().AsFpuRegister<XmmRegister>();
+ XmmRegister temp = locations->GetTemp(0).AsFpuRegister<XmmRegister>();
+ Register constant = locations->GetTemp(1).AsRegister<Register>();
+ __ movl(constant, Immediate(INT32_C(0x7FFFFFFF)));
+ __ movd(temp, constant);
+ __ andps(out, temp);
+ break;
+ }
+ case DataType::Type::kFloat64: {
+ XmmRegister out = locations->Out().AsFpuRegister<XmmRegister>();
+ XmmRegister temp = locations->GetTemp(0).AsFpuRegister<XmmRegister>();
+ // TODO: Use a constant from the constant table (requires extra input).
+ __ LoadLongConstant(temp, INT64_C(0x7FFFFFFFFFFFFFFF));
+ __ andpd(out, temp);
+ break;
+ }
+ default:
+ LOG(FATAL) << "Unexpected type for HAbs " << abs->GetResultType();
+ }
+}
+
void LocationsBuilderX86::VisitDivZeroCheck(HDivZeroCheck* instruction) {
LocationSummary* locations = codegen_->CreateThrowingSlowPathLocations(instruction);
switch (instruction->GetType()) {