Add trivial register hints to the register allocator.

- Add hints for phis, same as first input, and expected registers.
- Make the if instruction accept non-condition instructions.

Change-Id: I34fa68393f0d0c19c68128f017b7a05be556fbe5

1 files changed, 17 insertions, 0 deletions

diff --git a/compiler/optimizing/instruction_simplifier.cc b/compiler/optimizing/instruction_simplifier.cc
index a0de73d..2d9e35c 100644
--- a/compiler/optimizing/instruction_simplifier.cc
+++ b/compiler/optimizing/instruction_simplifier.cc
@@ -38,4 +38,21 @@ void InstructionSimplifier::VisitSuspendCheck(HSuspendCheck* check) {
   block->RemoveInstruction(check);
 }
 
+void InstructionSimplifier::VisitEqual(HEqual* equal) {
+  HInstruction* input1 = equal->InputAt(0);
+  HInstruction* input2 = equal->InputAt(1);
+  if (input1->GetType() == Primitive::kPrimBoolean && input2->IsIntConstant()) {
+    if (input2->AsIntConstant()->GetValue() == 1) {
+      // Replace (bool_value == 1) with bool_value
+      equal->ReplaceWith(equal->InputAt(0));
+      equal->GetBlock()->RemoveInstruction(equal);
+    } else {
+      // Replace (bool_value == 0) with !bool_value
+      DCHECK_EQ(input2->AsIntConstant()->GetValue(), 0);
+      equal->GetBlock()->ReplaceAndRemoveInstructionWith(
+          equal, new (GetGraph()->GetArena()) HNot(input1));
+    }
+  }
+}
+
 }  // namespace art