Revert "Revert "Revert "Revert "Change condition to opposite if lhs is constant""""
This reverts commit d4aee949b3dd976295201b5310f13aa2df40afa1.
Change-Id: I505b8c9863c310a3a708f580b00d425b750c9541
diff --git a/compiler/optimizing/instruction_simplifier.cc b/compiler/optimizing/instruction_simplifier.cc
index b95ece5..049901b 100644
--- a/compiler/optimizing/instruction_simplifier.cc
+++ b/compiler/optimizing/instruction_simplifier.cc
@@ -70,6 +70,10 @@
void VisitGreaterThanOrEqual(HGreaterThanOrEqual* condition) OVERRIDE;
void VisitLessThan(HLessThan* condition) OVERRIDE;
void VisitLessThanOrEqual(HLessThanOrEqual* condition) OVERRIDE;
+ void VisitBelow(HBelow* condition) OVERRIDE;
+ void VisitBelowOrEqual(HBelowOrEqual* condition) OVERRIDE;
+ void VisitAbove(HAbove* condition) OVERRIDE;
+ void VisitAboveOrEqual(HAboveOrEqual* condition) OVERRIDE;
void VisitDiv(HDiv* instruction) OVERRIDE;
void VisitMul(HMul* instruction) OVERRIDE;
void VisitNeg(HNeg* instruction) OVERRIDE;
@@ -559,6 +563,36 @@
block->RemoveInstruction(check);
}
+static HCondition* GetOppositeConditionSwapOps(ArenaAllocator* arena, HInstruction* cond) {
+ HInstruction *lhs = cond->InputAt(0);
+ HInstruction *rhs = cond->InputAt(1);
+ switch (cond->GetKind()) {
+ case HInstruction::kEqual:
+ return new (arena) HEqual(rhs, lhs);
+ case HInstruction::kNotEqual:
+ return new (arena) HNotEqual(rhs, lhs);
+ case HInstruction::kLessThan:
+ return new (arena) HGreaterThan(rhs, lhs);
+ case HInstruction::kLessThanOrEqual:
+ return new (arena) HGreaterThanOrEqual(rhs, lhs);
+ case HInstruction::kGreaterThan:
+ return new (arena) HLessThan(rhs, lhs);
+ case HInstruction::kGreaterThanOrEqual:
+ return new (arena) HLessThanOrEqual(rhs, lhs);
+ case HInstruction::kBelow:
+ return new (arena) HAbove(rhs, lhs);
+ case HInstruction::kBelowOrEqual:
+ return new (arena) HAboveOrEqual(rhs, lhs);
+ case HInstruction::kAbove:
+ return new (arena) HBelow(rhs, lhs);
+ case HInstruction::kAboveOrEqual:
+ return new (arena) HBelowOrEqual(rhs, lhs);
+ default:
+ LOG(FATAL) << "Unknown ConditionType " << cond->GetKind();
+ }
+ return nullptr;
+}
+
void InstructionSimplifierVisitor::VisitEqual(HEqual* equal) {
HInstruction* input_const = equal->GetConstantRight();
if (input_const != nullptr) {
@@ -982,13 +1016,47 @@
VisitCondition(condition);
}
-// TODO: unsigned comparisons too?
+void InstructionSimplifierVisitor::VisitBelow(HBelow* condition) {
+ VisitCondition(condition);
+}
+
+void InstructionSimplifierVisitor::VisitBelowOrEqual(HBelowOrEqual* condition) {
+ VisitCondition(condition);
+}
+
+void InstructionSimplifierVisitor::VisitAbove(HAbove* condition) {
+ VisitCondition(condition);
+}
+
+void InstructionSimplifierVisitor::VisitAboveOrEqual(HAboveOrEqual* condition) {
+ VisitCondition(condition);
+}
void InstructionSimplifierVisitor::VisitCondition(HCondition* condition) {
- // Try to fold an HCompare into this HCondition.
+ // Reverse condition if left is constant. Our code generators prefer constant
+ // on the right hand side.
+ if (condition->GetLeft()->IsConstant() && !condition->GetRight()->IsConstant()) {
+ HBasicBlock* block = condition->GetBlock();
+ HCondition* replacement = GetOppositeConditionSwapOps(block->GetGraph()->GetArena(), condition);
+ // If it is a fp we must set the opposite bias.
+ if (replacement != nullptr) {
+ if (condition->IsLtBias()) {
+ replacement->SetBias(ComparisonBias::kGtBias);
+ } else if (condition->IsGtBias()) {
+ replacement->SetBias(ComparisonBias::kLtBias);
+ }
+ block->ReplaceAndRemoveInstructionWith(condition, replacement);
+ RecordSimplification();
+
+ condition = replacement;
+ }
+ }
HInstruction* left = condition->GetLeft();
HInstruction* right = condition->GetRight();
+
+ // Try to fold an HCompare into this HCondition.
+
// We can only replace an HCondition which compares a Compare to 0.
// Both 'dx' and 'jack' generate a compare to 0 when compiling a
// condition with a long, float or double comparison as input.