More compact string representation on 64 bit.

runtime/platform/globals.h

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef RUNTIME_PLATFORM_GLOBALS_H_
 #define RUNTIME_PLATFORM_GLOBALS_H_
 
 // __STDC_FORMAT_MACROS has to be defined before including <inttypes.h> to
 // enable platform independent printf format specifiers.
 #ifndef __STDC_FORMAT_MACROS
@@ skipping 430 matching lines @@
 const int64_t kMaxInt64 = DART_INT64_C(0x7FFFFFFFFFFFFFFF);
 const uint64_t kMaxUint64 = DART_2PART_UINT64_C(0xFFFFFFFF, FFFFFFFF);
 const int64_t kSignBitDouble = DART_INT64_C(0x8000000000000000);
 
 // Types for native machine words. Guaranteed to be able to hold pointers and
 // integers.
 typedef intptr_t word;
 typedef uintptr_t uword;
 
 // Size of a class id.
-#if defined(ARCH_IS_32_BIT)
 typedef uint16_t classid_t;
-#elif defined(ARCH_IS_64_BIT)
-typedef uint32_t classid_t;
-#else
-#error Unexpected architecture word size
-#endif
 
 // Byte sizes.
 const int kWordSize = sizeof(word);
 const int kDoubleSize = sizeof(double);  // NOLINT
 const int kFloatSize = sizeof(float);    // NOLINT
 const int kQuadSize = 4 * kFloatSize;
 const int kSimd128Size = sizeof(simd128_value_t);  // NOLINT
 const int kInt64Size = sizeof(int64_t);            // NOLINT
 const int kInt32Size = sizeof(int32_t);            // NOLINT
 const int kInt16Size = sizeof(int16_t);            // NOLINT
@@ skipping 242 matching lines @@
 // tag in the ICData and check it when recreating the flow graph in
 // optimizing compiler. Enable it for other modes (product, release) if needed
 // for debugging.
 #if defined(DEBUG)
 #define TAG_IC_DATA
 #endif
 
 }  // namespace dart
 
 #endif  // RUNTIME_PLATFORM_GLOBALS_H_