[turbofan] Don't use the CompareIC in JSGenericLowering.

src/objects-inl.h

 // 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.
 //
 // Review notes:
 //
 // - The use of macros in these inline functions may seem superfluous
 // but it is absolutely needed to make sure gcc generates optimal
 // code. gcc is not happy when attempting to inline too deep.
 //
@@ skipping 1335 matching lines @@
           kExponentShift) - kExponentBias;
 }
 
 
 int HeapNumber::get_sign() {
   return READ_INT_FIELD(this, kExponentOffset) & kSignMask;
 }
 
 
 bool Simd128Value::Equals(Simd128Value* that) {
+  // TODO(bmeurer): This doesn't match the SIMD.js specification, but it seems
+  // to be consistent with what the CompareICStub does, and what is tested in
+  // the current SIMD.js testsuite.
+  if (this == that) return true;
 #define SIMD128_VALUE(TYPE, Type, type, lane_count, lane_type) \
   if (this->Is##Type()) {                                      \
     if (!that->Is##Type()) return false;                       \
     return Type::cast(this)->Equals(Type::cast(that));         \
   }
   SIMD128_TYPES(SIMD128_VALUE)
 #undef SIMD128_VALUE
   return false;
 }
 
@@ skipping 6319 matching lines @@
 #undef WRITE_INT64_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 #undef NOBARRIER_READ_BYTE_FIELD
 #undef NOBARRIER_WRITE_BYTE_FIELD
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_OBJECTS_INL_H_