Reorganize object type enum, such that proxies are no longer in the middle

src/ia32/lithium-codegen-ia32.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1726 matching lines @@
 // the temp registers, but not the input.  Only input and temp2 may alias.
 void LCodeGen::EmitClassOfTest(Label* is_true,
                                Label* is_false,
                                Handle<String>class_name,
                                Register input,
                                Register temp,
                                Register temp2) {
   ASSERT(!input.is(temp));
   ASSERT(!temp.is(temp2));  // But input and temp2 may be the same register.
   __ JumpIfSmi(input, is_false);
+
+  // Assuming the following assertions, we can do the same test for
+  // either "Object" or "Function", only the branch conditions differ.

[Erik Corry, 2011/09/15 09:13:46]

The test for Object involves two comparisons and two conditional jumps, but I
think the range is contiguous.  That means it could be done with a subtract, a
compare and an unsigned conditional branch.

[rossberg, 2011/09/15 14:06:07]

Done, here and in other backends.

+  STATIC_ASSERT(NUM_OF_CALLABLE_SPEC_OBJECT_TYPES == 2);
+  STATIC_ASSERT(FIRST_NONCALLABLE_SPEC_OBJECT_TYPE ==
+                FIRST_SPEC_OBJECT_TYPE + 1);
+  STATIC_ASSERT(LAST_NONCALLABLE_SPEC_OBJECT_TYPE ==
+                LAST_SPEC_OBJECT_TYPE - 1);
+  STATIC_ASSERT(LAST_SPEC_OBJECT_TYPE == LAST_TYPE);
+
+  // Functions have class 'Function'.
   __ CmpObjectType(input, FIRST_SPEC_OBJECT_TYPE, temp);
-  __ j(below, is_false);
-
   // Map is now in temp.
-  // Functions have class 'Function'.
-  __ CmpInstanceType(temp, FIRST_CALLABLE_SPEC_OBJECT_TYPE);
   if (class_name->IsEqualTo(CStrVector("Function"))) {
-    __ j(above_equal, is_true);
+    __ j(below, is_false);
+    __ j(equal, is_true);
+  } else {
+    __ j(below_equal, is_false);
+  }
+  __ CmpInstanceType(temp, LAST_SPEC_OBJECT_TYPE);
+  if (class_name->IsEqualTo(CStrVector("Function"))) {
+    __ j(equal, is_true);
   } else {
     __ j(above_equal, is_false);
   }
 
+  // Now we are in the FIRST-LAST_NONCALLABLE_SPEC_OBJECT_TYPE range.
   // Check if the constructor in the map is a function.
   __ mov(temp, FieldOperand(temp, Map::kConstructorOffset));
-
-  // As long as LAST_CALLABLE_SPEC_OBJECT_TYPE is the last instance type, and
-  // FIRST_CALLABLE_SPEC_OBJECT_TYPE comes right after
-  // LAST_NONCALLABLE_SPEC_OBJECT_TYPE, we can avoid checking for the latter.
-  STATIC_ASSERT(LAST_TYPE == LAST_CALLABLE_SPEC_OBJECT_TYPE);
-  STATIC_ASSERT(FIRST_CALLABLE_SPEC_OBJECT_TYPE ==
-                LAST_NONCALLABLE_SPEC_OBJECT_TYPE + 1);
-
   // Objects with a non-function constructor have class 'Object'.
   __ CmpObjectType(temp, JS_FUNCTION_TYPE, temp2);
   if (class_name->IsEqualTo(CStrVector("Object"))) {
     __ j(not_equal, is_true);
   } else {
     __ j(not_equal, is_false);
   }
 
   // temp now contains the constructor function. Grab the
   // instance class name from there.
@@ skipping 2401 matching lines @@
     __ cmp(input, factory()->undefined_value());
     __ j(equal, true_label);
     __ JumpIfSmi(input, false_label);
     // Check for undetectable objects => true.
     __ mov(input, FieldOperand(input, HeapObject::kMapOffset));
     __ test_b(FieldOperand(input, Map::kBitFieldOffset),
               1 << Map::kIsUndetectable);
     final_branch_condition = not_zero;
 
   } else if (type_name->Equals(heap()->function_symbol())) {
-    STATIC_ASSERT(LAST_TYPE == LAST_CALLABLE_SPEC_OBJECT_TYPE);
+    STATIC_ASSERT(NUM_OF_CALLABLE_SPEC_OBJECT_TYPES == 2);
     __ JumpIfSmi(input, false_label);
-    __ CmpObjectType(input, FIRST_CALLABLE_SPEC_OBJECT_TYPE, input);
-    final_branch_condition = above_equal;
+    __ CmpObjectType(input, JS_FUNCTION_TYPE, input);
+    __ j(equal, true_label);
+    __ CmpInstanceType(input, JS_FUNCTION_PROXY_TYPE);
+    final_branch_condition = equal;
 
   } else if (type_name->Equals(heap()->object_symbol())) {
     __ JumpIfSmi(input, false_label);
     if (!FLAG_harmony_typeof) {
       __ cmp(input, factory()->null_value());
       __ j(equal, true_label);
     }
     __ CmpObjectType(input, FIRST_NONCALLABLE_SPEC_OBJECT_TYPE, input);
     __ j(below, false_label);
     __ CmpInstanceType(input, LAST_NONCALLABLE_SPEC_OBJECT_TYPE);
@@ skipping 173 matching lines @@
                                          env->deoptimization_index());
   __ InvokeBuiltin(Builtins::IN, CALL_FUNCTION, safepoint_generator);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32