Improve polymorphic loads on single slots.

src/arm/lithium-arm.h

Index: src/arm/lithium-arm.h
diff --git a/src/arm/lithium-arm.h b/src/arm/lithium-arm.h
index 35ed67d6e746f49758f6033207def8f675f9f335..d882acd20aa405377f043a00465bd1bbfbd28e39 100644
--- a/src/arm/lithium-arm.h
+++ b/src/arm/lithium-arm.h
@@ -72,7 +72,7 @@ class LCodeGen;
   V(CheckFunction)                              \
   V(CheckInstanceType)                          \
   V(CheckNonSmi)                                \
-  V(CheckMap)                                   \
+  V(CheckMaps)                                  \
   V(CheckPrototypeMaps)                         \
   V(CheckSmi)                                   \
   V(ClampDToUint8)                              \
@@ -1839,14 +1839,14 @@ class LCheckInstanceType: public LTemplateInstruction<0, 1, 0> {
 };
 
 
-class LCheckMap: public LTemplateInstruction<0, 1, 0> {
+class LCheckMaps: public LTemplateInstruction<0, 1, 0> {
  public:
-  explicit LCheckMap(LOperand* value) {
+  explicit LCheckMaps(LOperand* value) {
     inputs_[0] = value;
   }
 
-  DECLARE_CONCRETE_INSTRUCTION(CheckMap, "check-map")
-  DECLARE_HYDROGEN_ACCESSOR(CheckMap)
+  DECLARE_CONCRETE_INSTRUCTION(CheckMaps, "check-maps")
+  DECLARE_HYDROGEN_ACCESSOR(CheckMaps)
 };