Simplify invocation sequence at monomorphic function invocation sites.

src/arm/lithium-codegen-arm.h

Index: src/arm/lithium-codegen-arm.h
diff --git a/src/arm/lithium-codegen-arm.h b/src/arm/lithium-codegen-arm.h
index adb6e1bb73e4ad6f70f4bc857e79968dfa4b7a32..d73581b2329bba63be4ffb14875c3807c184d770 100644
--- a/src/arm/lithium-codegen-arm.h
+++ b/src/arm/lithium-codegen-arm.h
@@ -215,12 +215,18 @@ class LCodeGen BASE_EMBEDDED {
                                int argc,
                                LInstruction* instr);
 
+  enum R1State {
+    R1_UNINITIALIZED,
+    R1_CONTAINS_TARGET
+  };
+
   // Generate a direct call to a known function.  Expects the function
   // to be in r1.
   void CallKnownFunction(Handle<JSFunction> function,
                          int arity,
                          LInstruction* instr,
-                         CallKind call_kind);
+                         CallKind call_kind,
+                         R1State r1_state);
 
   void LoadHeapObject(Register result, Handle<HeapObject> object);