ES6 symbols: turn symbols into a proper primitive type

src/ia32/full-codegen-ia32.cc

 // Copyright 2012 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 2549 matching lines @@
   __ j(below, if_false);
   __ cmp(ecx, LAST_NONCALLABLE_SPEC_OBJECT_TYPE);
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
   Split(below_equal, if_true, if_false, fall_through);
 
   context()->Plug(if_true, if_false);
 }
 
 
 void FullCodeGenerator::EmitIsSpecObject(CallRuntime* expr) {
-  // TODO(rossberg): incorporate symbols.
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
 
   VisitForAccumulatorValue(args->at(0));
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
   context()->PrepareTest(&materialize_true, &materialize_false,
@@ skipping 115 matching lines @@
   // default valueOf and set true result.
   __ or_(FieldOperand(ebx, Map::kBitField2Offset),
          Immediate(1 << Map::kStringWrapperSafeForDefaultValueOf));
   __ jmp(if_true);
 
   PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
   context()->Plug(if_true, if_false);
 }
 
 
-void FullCodeGenerator::EmitIsSymbol(CallRuntime* expr) {
-  ZoneList<Expression*>* args = expr->arguments();
-  ASSERT(args->length() == 1);
-
-  VisitForAccumulatorValue(args->at(0));
-
-  Label materialize_true, materialize_false;
-  Label* if_true = NULL;
-  Label* if_false = NULL;
-  Label* fall_through = NULL;
-  context()->PrepareTest(&materialize_true, &materialize_false,
-                         &if_true, &if_false, &fall_through);
-
-  __ JumpIfSmi(eax, if_false);
-  __ CmpObjectType(eax, SYMBOL_TYPE, ebx);
-  PrepareForBailoutBeforeSplit(expr, true, if_true, if_false);
-  Split(equal, if_true, if_false, fall_through);
-
-  context()->Plug(if_true, if_false);
-}
-
-
 void FullCodeGenerator::EmitIsFunction(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 1);
 
   VisitForAccumulatorValue(args->at(0));
 
   Label materialize_true, materialize_false;
   Label* if_true = NULL;
   Label* if_false = NULL;
   Label* fall_through = NULL;
@@ skipping 1530 matching lines @@
            isolate()->factory()->heap_number_map());
     Split(equal, if_true, if_false, fall_through);
   } else if (check->Equals(isolate()->heap()->string_string())) {
     __ JumpIfSmi(eax, if_false);
     __ CmpObjectType(eax, FIRST_NONSTRING_TYPE, edx);
     __ j(above_equal, if_false);
     // Check for undetectable objects => false.
     __ test_b(FieldOperand(edx, Map::kBitFieldOffset),
               1 << Map::kIsUndetectable);
     Split(zero, if_true, if_false, fall_through);
+  } else if (check->Equals(isolate()->heap()->symbol_string())) {
+    __ JumpIfSmi(eax, if_false);
+    __ CmpObjectType(eax, SYMBOL_TYPE, edx);
+    Split(equal, if_true, if_false, fall_through);
   } else if (check->Equals(isolate()->heap()->boolean_string())) {
     __ cmp(eax, isolate()->factory()->true_value());
     __ j(equal, if_true);
     __ cmp(eax, isolate()->factory()->false_value());
     Split(equal, if_true, if_false, fall_through);
   } else if (FLAG_harmony_typeof &&
              check->Equals(isolate()->heap()->null_string())) {
     __ cmp(eax, isolate()->factory()->null_value());
     Split(equal, if_true, if_false, fall_through);
   } else if (check->Equals(isolate()->heap()->undefined_string())) {
@@ skipping 11 matching lines @@
     __ CmpObjectType(eax, JS_FUNCTION_TYPE, edx);
     __ j(equal, if_true);
     __ CmpInstanceType(edx, JS_FUNCTION_PROXY_TYPE);
     Split(equal, if_true, if_false, fall_through);
   } else if (check->Equals(isolate()->heap()->object_string())) {
     __ JumpIfSmi(eax, if_false);
     if (!FLAG_harmony_typeof) {
       __ cmp(eax, isolate()->factory()->null_value());
       __ j(equal, if_true);
     }
-    if (FLAG_harmony_symbols) {
-      __ CmpObjectType(eax, SYMBOL_TYPE, edx);
-      __ j(equal, if_true);
-    }
     __ CmpObjectType(eax, FIRST_NONCALLABLE_SPEC_OBJECT_TYPE, edx);
     __ j(below, if_false);
     __ CmpInstanceType(edx, LAST_NONCALLABLE_SPEC_OBJECT_TYPE);
     __ j(above, if_false);
     // Check for undetectable objects => false.
     __ test_b(FieldOperand(edx, Map::kBitFieldOffset),
               1 << Map::kIsUndetectable);
     Split(zero, if_true, if_false, fall_through);
   } else {
     if (if_false != fall_through) __ jmp(if_false);
@@ skipping 250 matching lines @@
   *stack_depth = 0;
   *context_length = 0;
   return previous_;
 }
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_IA32