Fix ARM code generator for Select.
Handle the case the output aliases with an input of an "emit-at-use-site"
condition.
Test: 684-select-condition
bug: 116169970
Change-Id: I7d67e90d44f6e715210c6a8abb8baa0342a7e7c5
diff --git a/compiler/optimizing/code_generator_arm_vixl.cc b/compiler/optimizing/code_generator_arm_vixl.cc
index d5149b3..17d9736 100644
--- a/compiler/optimizing/code_generator_arm_vixl.cc
+++ b/compiler/optimizing/code_generator_arm_vixl.cc
@@ -2677,6 +2677,18 @@
const Location first = locations->InAt(0);
const Location out = locations->Out();
const Location second = locations->InAt(1);
+
+ // In the unlucky case the output of this instruction overlaps
+ // with an input of an "emitted-at-use-site" condition, and
+ // the output of this instruction is not one of its inputs, we'll
+ // need to fallback to branches instead of conditional ARM instructions.
+ bool output_overlaps_with_condition_inputs =
+ !IsBooleanValueOrMaterializedCondition(condition) &&
+ !out.Equals(first) &&
+ !out.Equals(second) &&
+ (condition->GetLocations()->InAt(0).Equals(out) ||
+ condition->GetLocations()->InAt(1).Equals(out));
+ DCHECK(!output_overlaps_with_condition_inputs || condition->IsCondition());
Location src;
if (condition->IsIntConstant()) {
@@ -2690,7 +2702,7 @@
return;
}
- if (!DataType::IsFloatingPointType(type)) {
+ if (!DataType::IsFloatingPointType(type) && !output_overlaps_with_condition_inputs) {
bool invert = false;
if (out.Equals(second)) {
@@ -2762,6 +2774,7 @@
vixl32::Label* false_target = nullptr;
vixl32::Label* true_target = nullptr;
vixl32::Label select_end;
+ vixl32::Label other_case;
vixl32::Label* const target = codegen_->GetFinalLabel(select, &select_end);
if (out.Equals(second)) {
@@ -2772,12 +2785,21 @@
src = second;
if (!out.Equals(first)) {
- codegen_->MoveLocation(out, first, type);
+ if (output_overlaps_with_condition_inputs) {
+ false_target = &other_case;
+ } else {
+ codegen_->MoveLocation(out, first, type);
+ }
}
}
GenerateTestAndBranch(select, 2, true_target, false_target, /* far_target */ false);
codegen_->MoveLocation(out, src, type);
+ if (output_overlaps_with_condition_inputs) {
+ __ B(target);
+ __ Bind(&other_case);
+ codegen_->MoveLocation(out, first, type);
+ }
if (select_end.IsReferenced()) {
__ Bind(&select_end);
@@ -2876,31 +2898,16 @@
void LocationsBuilderARMVIXL::HandleCondition(HCondition* cond) {
LocationSummary* locations =
new (GetGraph()->GetAllocator()) LocationSummary(cond, LocationSummary::kNoCall);
- // Handle the long/FP comparisons made in instruction simplification.
- switch (cond->InputAt(0)->GetType()) {
- case DataType::Type::kInt64:
- locations->SetInAt(0, Location::RequiresRegister());
- locations->SetInAt(1, Location::RegisterOrConstant(cond->InputAt(1)));
- if (!cond->IsEmittedAtUseSite()) {
- locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
- }
- break;
-
- case DataType::Type::kFloat32:
- case DataType::Type::kFloat64:
- locations->SetInAt(0, Location::RequiresFpuRegister());
- locations->SetInAt(1, ArithmeticZeroOrFpuRegister(cond->InputAt(1)));
- if (!cond->IsEmittedAtUseSite()) {
- locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
- }
- break;
-
- default:
- locations->SetInAt(0, Location::RequiresRegister());
- locations->SetInAt(1, Location::RegisterOrConstant(cond->InputAt(1)));
- if (!cond->IsEmittedAtUseSite()) {
- locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
- }
+ const DataType::Type type = cond->InputAt(0)->GetType();
+ if (DataType::IsFloatingPointType(type)) {
+ locations->SetInAt(0, Location::RequiresFpuRegister());
+ locations->SetInAt(1, ArithmeticZeroOrFpuRegister(cond->InputAt(1)));
+ } else {
+ locations->SetInAt(0, Location::RequiresRegister());
+ locations->SetInAt(1, Location::RegisterOrConstant(cond->InputAt(1)));
+ }
+ if (!cond->IsEmittedAtUseSite()) {
+ locations->SetOut(Location::RequiresRegister(), Location::kNoOutputOverlap);
}
}