[es6] When comparing two symbols we may need to throw a TypeError

src/x87/code-stubs-x87.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_X87
 
 #include "src/base/bits.h"
 #include "src/bootstrapper.h"
@@ skipping 1367 matching lines @@
 
     // Test for NaN. Compare heap numbers in a general way,
     // to hanlde NaNs correctly.
     __ cmp(FieldOperand(edx, HeapObject::kMapOffset),
            Immediate(isolate()->factory()->heap_number_map()));
     __ j(equal, &generic_heap_number_comparison, Label::kNear);
     if (cc != equal) {
       // Call runtime on identical JSObjects.  Otherwise return equal.
       __ CmpObjectType(eax, FIRST_SPEC_OBJECT_TYPE, ecx);
       __ j(above_equal, &not_identical);
+      // Call runtime on identical symbols since we need to throw a TypeError.
+      __ CmpObjectType(eax, SYMBOL_TYPE, ecx);
+      __ j(equal, &not_identical);
     }
     __ Move(eax, Immediate(Smi::FromInt(EQUAL)));
     __ ret(0);
 
 
     __ bind(&not_identical);
   }
 
   // Strict equality can quickly decide whether objects are equal.
   // Non-strict object equality is slower, so it is handled later in the stub.
@@ skipping 3669 matching lines @@
                            ApiParameterOperand(2), kStackSpace, nullptr,
                            Operand(ebp, 7 * kPointerSize), NULL);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X87