Constant folding on unary operations in the optimizing compiler.

Change-Id: I4b77afa2a89f5ad2eedd4d6c0c6c382585419349

1 files changed, 11 insertions, 3 deletions

diff --git a/compiler/optimizing/constant_folding.cc b/compiler/optimizing/constant_folding.cc
index 0b3ad9809f..10a7e46299 100644
--- a/compiler/optimizing/constant_folding.cc
+++ b/compiler/optimizing/constant_folding.cc
@@ -31,11 +31,19 @@ void HConstantFolding::Run() {
     for (HInstructionIterator it(block->GetInstructions());
          !it.Done(); it.Advance()) {
       HInstruction* inst = it.Current();
-      // Constant folding: replace `c <- a op b' with a compile-time
-      // evaluation of `a op b' if `a' and `b' are constant.
       if (inst->IsBinaryOperation()) {
+        // Constant folding: replace `op(a, b)' with a constant at
+        // compile time if `a' and `b' are both constants.
         HConstant* constant =
-          inst->AsBinaryOperation()->TryStaticEvaluation(graph_->GetArena());
+            inst->AsBinaryOperation()->TryStaticEvaluation();
+        if (constant != nullptr) {
+          inst->GetBlock()->ReplaceAndRemoveInstructionWith(inst, constant);
+        }
+      } else if (inst->IsUnaryOperation()) {
+        // Constant folding: replace `op(a)' with a constant at compile
+        // time if `a' is a constant.
+        HConstant* constant =
+            inst->AsUnaryOperation()->TryStaticEvaluation();
         if (constant != nullptr) {
           inst->GetBlock()->ReplaceAndRemoveInstructionWith(inst, constant);
         }