util.h: getbe32() and putbe32() use intrinsic function to improve performance
Refer to https://bugzilla.mozilla.org/show_bug.cgi?id=351557. It can improve
byte-swapping performance by intrinsic function.
--- a/mercurial/util.h Fri Sep 06 13:30:58 2013 +0400
+++ b/mercurial/util.h Sat Sep 14 11:22:34 2013 +0800
@@ -151,6 +151,17 @@
#define inline __inline
#endif
+#if defined(_MSC_VER) && (_MSC_VER >= 1300)
+static inline uint32_t getbe32(const char *c)
+{
+ return _byteswap_ulong(*(uint32_t *)c);
+}
+#elif GCC_VERSION >= 403
+static inline uint32_t getbe32(const char *c)
+{
+ return __builtin_bswap32(*(uint32_t *)c);
+}
+#else
static inline uint32_t getbe32(const char *c)
{
const unsigned char *d = (const unsigned char *)c;
@@ -160,7 +171,21 @@
(d[2] << 8) |
(d[3]));
}
+#endif
+#if defined(_MSC_VER) && (_MSC_VER >= 1300)
+static inline void putbe32(uint32_t x, char *c)
+{
+ x = _byteswap_ulong(x);
+ *(uint32_t *)c = x;
+}
+#elif GCC_VERSION >= 403
+static inline void putbe32(uint32_t x, char *c)
+{
+ x = __builtin_bswap32(x);
+ *(uint32_t *)c = x;
+}
+#else
static inline void putbe32(uint32_t x, char *c)
{
c[0] = (x >> 24) & 0xff;
@@ -168,5 +193,6 @@
c[2] = (x >> 8) & 0xff;
c[3] = (x) & 0xff;
}
+#endif
#endif /* _HG_UTIL_H_ */