ART: Implement HSelect
This patch adds a new HIR instruction to Optimizing. HSelect returns
one of two inputs based on the outcome of a condition.
This is only initial implementation which:
- defines the new instruction,
- repurposes BooleanSimplifier to emit it,
- extends InstructionSimplifier to statically resolve it,
- updates existing code and tests accordingly.
Code generators currently emit fallback if/then/else code and will be
updated in follow-up CLs to use platform-specific conditional moves
when possible.
Change-Id: Ib61b17146487ebe6b55350c2b589f0b971dcaaee
diff --git a/compiler/optimizing/code_generator_arm64.cc b/compiler/optimizing/code_generator_arm64.cc
index 788c3a6..ec5ca3d 100644
--- a/compiler/optimizing/code_generator_arm64.cc
+++ b/compiler/optimizing/code_generator_arm64.cc
@@ -3004,6 +3004,32 @@
/* false_target */ nullptr);
}
+void LocationsBuilderARM64::VisitSelect(HSelect* select) {
+ LocationSummary* locations = new (GetGraph()->GetArena()) LocationSummary(select);
+ if (Primitive::IsFloatingPointType(select->GetType())) {
+ locations->SetInAt(0, Location::RequiresFpuRegister());
+ locations->SetInAt(1, Location::RequiresFpuRegister());
+ } else {
+ locations->SetInAt(0, Location::RequiresRegister());
+ locations->SetInAt(1, Location::RequiresRegister());
+ }
+ if (IsBooleanValueOrMaterializedCondition(select->GetCondition())) {
+ locations->SetInAt(2, Location::RequiresRegister());
+ }
+ locations->SetOut(Location::SameAsFirstInput());
+}
+
+void InstructionCodeGeneratorARM64::VisitSelect(HSelect* select) {
+ LocationSummary* locations = select->GetLocations();
+ vixl::Label false_target;
+ GenerateTestAndBranch(select,
+ /* condition_input_index */ 2,
+ /* true_target */ nullptr,
+ &false_target);
+ codegen_->MoveLocation(locations->Out(), locations->InAt(1), select->GetType());
+ __ Bind(&false_target);
+}
+
void LocationsBuilderARM64::VisitNativeDebugInfo(HNativeDebugInfo* info) {
new (GetGraph()->GetArena()) LocationSummary(info);
}