Add HLoadRoot hydrogen instruction.

src/ia32/lithium-ia32.h

Index: src/ia32/lithium-ia32.h
diff --git a/src/ia32/lithium-ia32.h b/src/ia32/lithium-ia32.h
index 0e615f257dfbde7039da1ff8b7e8f004ab342fe8..92bcbcfad2c18bf1cb621f87ed562496c7cda831 100644
--- a/src/ia32/lithium-ia32.h
+++ b/src/ia32/lithium-ia32.h
@@ -130,6 +130,7 @@ class LCodeGen;
   V(LoadKeyedGeneric)                           \
   V(LoadNamedField)                             \
   V(LoadNamedGeneric)                           \
+  V(LoadRoot)                                   \
   V(MapEnumLength)                              \
   V(MathAbs)                                    \
   V(MathCos)                                    \
@@ -1605,6 +1606,15 @@ class LLoadFunctionPrototype V8_FINAL : public LTemplateInstruction<1, 1, 1> {
 };
 
 
+class LLoadRoot V8_FINAL : public LTemplateInstruction<1, 0, 0> {
+ public:
+  DECLARE_CONCRETE_INSTRUCTION(LoadRoot, "load-root")
+  DECLARE_HYDROGEN_ACCESSOR(LoadRoot)
+
+  Heap::RootListIndex index() const { return hydrogen()->index(); }
+};
+
+
 class LLoadExternalArrayPointer V8_FINAL
     : public LTemplateInstruction<1, 1, 0> {
  public: