Clarify precedence of operations involving bitwise and(&) in x64/assembler.

src/x64/assembler-x64.h

 // Copyright (c) 1994-2006 Sun Microsystems Inc.
 // 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.
 //
@@ skipping 27 matching lines @@
 #define V8_X64_ASSEMBLER_X64_H_
 
 namespace v8 {
 namespace internal {
 
 // Utility functions
 
 // Test whether a 64-bit value is in a specific range.
 static inline bool is_uint32(int64_t x) {
   const int64_t kUInt32Mask = V8_INT64_C(0xffffffff);
-  return x == x & kUInt32Mask;
+  return x == (x & kUInt32Mask);
 }
 
 static inline bool is_int32(int64_t x) {
   const int64_t kMinIntValue = V8_INT64_C(-0x80000000);
   return is_uint32(x - kMinIntValue);
 }
 
 // CPU Registers.
 //
 // 1) We would prefer to use an enum, but enum values are assignment-
@@ skipping 1033 matching lines @@
  private:
   Assembler* assembler_;
 #ifdef DEBUG
   int space_before_;
 #endif
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_X64_ASSEMBLER_X64_H_