Elide unnecessary context reload in generated stubs.

src/lithium-allocator-inl.h

Index: src/lithium-allocator-inl.h
diff --git a/src/lithium-allocator-inl.h b/src/lithium-allocator-inl.h
index 8f660ce0e00373bdd5521b183527e972fc68c75c..29b81848ceb33fc188b897da526ec9a56235d7bf 100644
--- a/src/lithium-allocator-inl.h
+++ b/src/lithium-allocator-inl.h
@@ -110,7 +110,10 @@ void InputIterator::Advance() {
 
 
 void InputIterator::SkipUninteresting() {
-  while (current_ < limit_ && instr_->InputAt(current_)->IsConstantOperand()) {
+  LOperand* current;
+  while (current_ < limit_ &&
+         (current = instr_->InputAt(current_)) != NULL &&

[ulan, 2012/12/28 15:40:49]

Looks like we can make NULL operands uninteresting by changing it to ((current =
instr_->InputAt(current_)) == NULL || current->IsConstantOperand()).
Then we can avoid if (it.Current() == NULL) checks in the .cc file.

[danno, 2012/12/28 17:38:41]

Done.

+         current->IsConstantOperand()) {
     ++current_;
   }
 }