Revert "Remove support for MSVC"

sky/engine/wtf/ByteSwap.h

 /*
  * Copyright (C) 2013 Google 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.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 18 matching lines @@
  */
 
 #ifndef WTF_ByteSwap_h
 #define WTF_ByteSwap_h
 
 #include "wtf/CPU.h"
 #include "wtf/Compiler.h"
 
 #include <stdint.h>
 
+#if COMPILER(MSVC)
+#include <stdlib.h>
+#endif
+
 namespace WTF {
 
 inline uint32_t wswap32(uint32_t x) { return ((x & 0xffff0000) >> 16) | ((x & 0x0000ffff) << 16); }
 
+#if COMPILER(MSVC)
+
+ALWAYS_INLINE uint64_t bswap64(uint64_t x) { return _byteswap_uint64(x); }
+ALWAYS_INLINE uint32_t bswap32(uint32_t x) { return _byteswap_ulong(x); }
+ALWAYS_INLINE uint16_t bswap16(uint16_t x) { return _byteswap_ushort(x); }
+
+#else
+
 ALWAYS_INLINE uint64_t bswap64(uint64_t x) { return __builtin_bswap64(x); }
 ALWAYS_INLINE uint32_t bswap32(uint32_t x) { return __builtin_bswap32(x); }
 // GCC 4.6 lacks __builtin_bswap16. Newer versions have it but we support 4.6.
 #if COMPILER(CLANG)
 ALWAYS_INLINE uint16_t bswap16(uint16_t x) { return __builtin_bswap16(x); }
 #else
 inline uint16_t bswap16(uint16_t x) { return ((x & 0xff00) >> 8) | ((x & 0x00ff) << 8); }
 #endif
 
+#endif
+
 #if CPU(64BIT)
 
 ALWAYS_INLINE size_t bswapuintptrt(size_t x) { return bswap64(x); }
 
 #else
 
 ALWAYS_INLINE size_t bswapuintptrt(size_t x) { return bswap32(x); }
 
 #endif
 
 } // namespace WTF
 
 #endif // WTF_ByteSwap_h