diff options
| author | Mans Rullgard <mans@mansr.com> | 2011-12-12 00:50:08 +0000 |
|---|---|---|
| committer | Mans Rullgard <mans@mansr.com> | 2011-12-12 12:14:14 +0000 |
| commit | f64c2e710fa1a7b59753224e717f57c48462076f (patch) | |
| tree | 760f8b52024f89e22778498c4f00ceac03f3f01e /libavutil | |
| parent | 5695ae46f8771f5c63cb0f62faca6a3d27f7d921 (diff) | |
| download | ffmpeg-f64c2e710fa1a7b59753224e717f57c48462076f.tar.gz | |
bswap: make generic implementation more compiler-friendly
With these changes, gcc 4.5 and later recognise it as a bswap
and use the proper instructions on ARM and x86. On x86, the
16-bit bswap is recognised from gcc 4.1.
Signed-off-by: Mans Rullgard <mans@mansr.com>
Diffstat (limited to 'libavutil')
| -rw-r--r-- | libavutil/arm/bswap.h | 2 | ||||
| -rw-r--r-- | libavutil/bswap.h | 13 | ||||
| -rw-r--r-- | libavutil/x86/bswap.h | 4 |
3 files changed, 8 insertions, 11 deletions
diff --git a/libavutil/arm/bswap.h b/libavutil/arm/bswap.h index 478ae981fb..f94cbcf23f 100644 --- a/libavutil/arm/bswap.h +++ b/libavutil/arm/bswap.h @@ -51,6 +51,7 @@ static av_always_inline av_const unsigned av_bswap16(unsigned x) } #endif +#if !AV_GCC_VERSION_AT_LEAST(4,5) #define av_bswap32 av_bswap32 static av_always_inline av_const uint32_t av_bswap32(uint32_t x) { @@ -66,6 +67,7 @@ static av_always_inline av_const uint32_t av_bswap32(uint32_t x) #endif /* HAVE_ARMV6 */ return x; } +#endif /* !AV_GCC_VERSION_AT_LEAST(4,5) */ #endif /* __ARMCC_VERSION */ diff --git a/libavutil/bswap.h b/libavutil/bswap.h index 3657ccd402..8a350e1cd5 100644 --- a/libavutil/bswap.h +++ b/libavutil/bswap.h @@ -65,23 +65,14 @@ static av_always_inline av_const uint16_t av_bswap16(uint16_t x) #ifndef av_bswap32 static av_always_inline av_const uint32_t av_bswap32(uint32_t x) { - x= ((x<<8)&0xFF00FF00) | ((x>>8)&0x00FF00FF); - x= (x>>16) | (x<<16); - return x; + return AV_BSWAP32C(x); } #endif #ifndef av_bswap64 static inline uint64_t av_const av_bswap64(uint64_t x) { - union { - uint64_t ll; - uint32_t l[2]; - } w, r; - w.ll = x; - r.l[0] = av_bswap32 (w.l[1]); - r.l[1] = av_bswap32 (w.l[0]); - return r.ll; + return (uint64_t)av_bswap32(x) << 32 | av_bswap32(x >> 32); } #endif diff --git a/libavutil/x86/bswap.h b/libavutil/x86/bswap.h index b60d9ccd6c..6840b632cb 100644 --- a/libavutil/x86/bswap.h +++ b/libavutil/x86/bswap.h @@ -28,13 +28,16 @@ #include "config.h" #include "libavutil/attributes.h" +#if !AV_GCC_VERSION_AT_LEAST(4,1) #define av_bswap16 av_bswap16 static av_always_inline av_const unsigned av_bswap16(unsigned x) { __asm__("rorw $8, %w0" : "+r"(x)); return x; } +#endif /* !AV_GCC_VERSION_AT_LEAST(4,1) */ +#if !AV_GCC_VERSION_AT_LEAST(4,5) #define av_bswap32 av_bswap32 static av_always_inline av_const uint32_t av_bswap32(uint32_t x) { @@ -57,5 +60,6 @@ static inline uint64_t av_const av_bswap64(uint64_t x) return x; } #endif +#endif /* !AV_GCC_VERSION_AT_LEAST(4,5) */ #endif /* AVUTIL_X86_BSWAP_H */ |