Make RegExp objects not callable.

src/ia32/lithium-codegen-ia32.cc

Index: src/ia32/lithium-codegen-ia32.cc
diff --git a/src/ia32/lithium-codegen-ia32.cc b/src/ia32/lithium-codegen-ia32.cc
index 62f4c656f456b02dd0fd62bab669a9dfb385c4ae..8d2dfd5b3937efae843383e73e5651784f6f2e4f 100644
--- a/src/ia32/lithium-codegen-ia32.cc
+++ b/src/ia32/lithium-codegen-ia32.cc
@@ -4281,17 +4281,13 @@ Condition LCodeGen::EmitTypeofIs(Label* true_label,
 
   } else if (type_name->Equals(heap()->function_symbol())) {
     __ JumpIfSmi(input, false_label);
-    __ CmpObjectType(input, JS_FUNCTION_TYPE, input);
-    __ j(equal, true_label);
-    // Regular expressions => 'function' (they are callable).
-    __ CmpInstanceType(input, JS_REGEXP_TYPE);
-    final_branch_condition = equal;
+    __ CmpObjectType(input, FIRST_FUNCTION_CLASS_TYPE, input);
+    final_branch_condition = above_equal;
 
   } else if (type_name->Equals(heap()->object_symbol())) {
     __ JumpIfSmi(input, false_label);
     __ cmp(input, factory()->null_value());
     __ j(equal, true_label);
-    // Regular expressions => 'function', not 'object'.
     __ CmpObjectType(input, FIRST_JS_OBJECT_TYPE, input);
     __ j(below, false_label);
     __ CmpInstanceType(input, FIRST_FUNCTION_CLASS_TYPE);