Fix variable decl register collision on ARM.

src/arm/full-codegen-arm.cc

Index: src/arm/full-codegen-arm.cc
diff --git a/src/arm/full-codegen-arm.cc b/src/arm/full-codegen-arm.cc
index 0bcb6a79ccd30154943cb7e363ca9fca50f3de6b..254089ab0bb37ea8194de8a977ab6dbf15bf77ca 100644
--- a/src/arm/full-codegen-arm.cc
+++ b/src/arm/full-codegen-arm.cc
@@ -864,8 +864,8 @@ void FullCodeGenerator::VisitVariableDeclaration(
     case Variable::LOCAL:
       if (hole_init) {
         Comment cmnt(masm_, "[ VariableDeclaration");
-        __ LoadRoot(ip, Heap::kTheHoleValueRootIndex);
-        __ str(ip, StackOperand(variable));
+        __ LoadRoot(r0, Heap::kTheHoleValueRootIndex);
+        __ str(r0, StackOperand(variable));

[Dmitry Lomov (no reviews), 2015/03/28 10:41:18]

Actually there are more usages of ip below this, see line 876.
I am a bit surprised that this change fixes anything, since currently variables
that need hole-init are not stack allocated

[Jarin, 2015/03/30 05:54:50]

Well, the test case is not really valid code (it re-assigns a const variable),
so it might well be that we get a bit confused. However, I have verified that
this change "fixes" the regression test.

       }
       break;