Fix array index dehoisting.

src/hydrogen.cc

Index: src/hydrogen.cc
diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index 75344bb513a0d13365ba32bff60330cd2a521301..66e69dc46bf3e102e4dd55e8f3dbbb15b7ee007b 100644
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -3748,6 +3748,8 @@ static void DehoistArrayIndex(ArrayInstructionInterface* array_operation) {
   HValue* subexpression;
   int32_t sign;
   if (index->IsAdd()) {
+    if (!index->representation().IsInteger32())
+      return;

[Jakob Kummerow, 2012/09/11 13:16:24]

{} please (or put it all on one line).
Again below.

Also, you could do with a single copy of this condition if you move it up and
out of the if-block.

     sign = 1;
     HAdd* add = HAdd::cast(index);
     if (add->left()->IsConstant()) {
@@ -3760,6 +3762,8 @@ static void DehoistArrayIndex(ArrayInstructionInterface* array_operation) {
       return;
     }
   } else if (index->IsSub()) {
+    if (!index->representation().IsInteger32())
+      return;
     sign = -1;
     HSub* sub = HSub::cast(index);
     if (sub->left()->IsConstant()) {