Implement hardfloat calling convention in macro assembler and simulator.

src/assembler.h

Index: src/assembler.h
diff --git a/src/assembler.h b/src/assembler.h
index e8cecc3fdb941cbf02081ba5d60a8462b6c0e974..587650c061454609a9a80ff2e5938b70a6c32c1b 100644
--- a/src/assembler.h
+++ b/src/assembler.h
@@ -503,7 +503,15 @@ class ExternalReference BASE_EMBEDDED {
 
     // Builtin call that returns floating point.
     // double f(double, double).
-    FP_RETURN_CALL,
+    BUILTIN_FP_FP_CALL,
+
+    // Builtin call that returns floating point.
+    // double f(double).
+    BUILTIN_FP_CALL,
+
+    // Builtin call that returns floating point.
+    // double f(double, int).
+    BUILTIN_FP_INT_CALL,
 
     // Direct call to API function callback.
     // Handle<Value> f(v8::Arguments&)