From 18770dac2e560c88daa3ca9944917be561c3548f Mon Sep 17 00:00:00 2001 From: Michael Sevakis Date: Sun, 30 Jan 2011 00:58:45 +0000 Subject: Use __builtin_constant_p() to select the best byteswapping method: constant or target optimized. Same macro can then be used for constant values and inits as well as non-constant. git-svn-id: svn://svn.rockbox.org/rockbox/trunk@29171 a1c6a512-1295-4272-9138-f99709370657 --- firmware/export/system.h | 129 +++++++++++++++++++++++++---------------------- 1 file changed, 69 insertions(+), 60 deletions(-) (limited to 'firmware/export') diff --git a/firmware/export/system.h b/firmware/export/system.h index 4a5dcf0ea3..b246d154a4 100644 --- a/firmware/export/system.h +++ b/firmware/export/system.h @@ -137,61 +137,6 @@ int get_cpu_boost_counter(void); #undef htobe32 #endif -/* live endianness conversion */ -#ifdef ROCKBOX_LITTLE_ENDIAN -#define letoh16(x) (x) -#define letoh32(x) (x) -#define htole16(x) (x) -#define htole32(x) (x) -#define betoh16(x) swap16(x) -#define betoh32(x) swap32(x) -#define htobe16(x) swap16(x) -#define htobe32(x) swap32(x) -#define swap_odd_even_be32(x) (x) -#define swap_odd_even_le32(x) swap_odd_even32(x) -#else -#define letoh16(x) swap16(x) -#define letoh32(x) swap32(x) -#define htole16(x) swap16(x) -#define htole32(x) swap32(x) -#define betoh16(x) (x) -#define betoh32(x) (x) -#define htobe16(x) (x) -#define htobe32(x) (x) -#define swap_odd_even_be32(x) swap_odd_even32(x) -#define swap_odd_even_le32(x) (x) -#endif - - -/* static endianness conversion */ -#define SWAP_16(x) ((typeof(x))(unsigned short)(((unsigned short)(x) >> 8) | \ - ((unsigned short)(x) << 8))) - -#define SWAP_32(x) ((typeof(x))(unsigned long)( ((unsigned long)(x) >> 24) | \ - (((unsigned long)(x) & 0xff0000ul) >> 8) | \ - (((unsigned long)(x) & 0xff00ul) << 8) | \ - ((unsigned long)(x) << 24))) - -#ifdef ROCKBOX_LITTLE_ENDIAN -#define LE_TO_H16(x) (x) -#define LE_TO_H32(x) (x) -#define H_TO_LE16(x) (x) -#define H_TO_LE32(x) (x) -#define BE_TO_H16(x) SWAP_16(x) -#define BE_TO_H32(x) SWAP_32(x) -#define H_TO_BE16(x) SWAP_16(x) -#define H_TO_BE32(x) SWAP_32(x) -#else -#define LE_TO_H16(x) SWAP_16(x) -#define LE_TO_H32(x) SWAP_32(x) -#define H_TO_LE16(x) SWAP_16(x) -#define H_TO_LE32(x) SWAP_32(x) -#define BE_TO_H16(x) (x) -#define BE_TO_H32(x) (x) -#define H_TO_BE16(x) (x) -#define H_TO_BE32(x) (x) -#endif - /* Get the byte offset of a type's member */ #define OFFSETOF(type, membername) ((off_t)&((type *)0)->membername) @@ -237,7 +182,7 @@ enum { #endif #ifdef NEED_GENERIC_BYTESWAPS -static inline uint16_t swap16(uint16_t value) +static inline uint16_t swap16_hw(uint16_t value) /* result[15..8] = value[ 7..0]; result[ 7..0] = value[15..8]; @@ -246,7 +191,7 @@ static inline uint16_t swap16(uint16_t value) return (value >> 8) | (value << 8); } -static inline uint32_t swap32(uint32_t value) +static inline uint32_t swap32_hw(uint32_t value) /* result[31..24] = value[ 7.. 0]; result[23..16] = value[15.. 8]; @@ -254,12 +199,12 @@ static inline uint32_t swap32(uint32_t value) result[ 7.. 0] = value[31..24]; */ { - uint32_t hi = swap16(value >> 16); - uint32_t lo = swap16(value & 0xffff); + uint32_t hi = swap16_hw(value >> 16); + uint32_t lo = swap16_hw(value & 0xffff); return (lo << 16) | hi; } -static inline uint32_t swap_odd_even32(uint32_t value) +static inline uint32_t swap_odd_even32_hw(uint32_t value) { /* result[31..24],[15.. 8] = value[23..16],[ 7.. 0] @@ -269,8 +214,72 @@ static inline uint32_t swap_odd_even32(uint32_t value) return (t >> 8) | ((t ^ value) << 8); } +static inline uint32_t swaw32_hw(uint32_t value) +{ + /* + result[31..16] = value[15.. 0]; + result[15.. 0] = value[31..16]; + */ + return (value >> 16) | (value << 16); +} + #endif /* NEED_GENERIC_BYTESWAPS */ +/* static endianness conversion */ +#define SWAP16_CONST(x) \ + ((typeof(x))( ((uint16_t)(x) >> 8) | ((uint16_t)(x) << 8) )) + +#define SWAP32_CONST(x) \ + ((typeof(x))( ((uint32_t)(x) >> 24) | \ + (((uint32_t)(x) & 0xff0000) >> 8) | \ + (((uint32_t)(x) & 0xff00) << 8) | \ + ((uint32_t)(x) << 24) )) + +#define SWAP_ODD_EVEN32_CONST(x) \ + ((typeof(x))( ((uint32_t)SWAP16_CONST((uint32_t)(x) >> 16) << 16) | \ + SWAP16_CONST((uint32_t)(x))) ) + +#define SWAW32_CONST(x) \ + ((typeof(x))( ((uint32_t)(x) << 16) | ((uint32_t)(x) >> 16) )) + +/* Select best method based upon whether x is a constant expression */ +#define swap16(x) \ + ( __builtin_constant_p(x) ? SWAP16_CONST(x) : (typeof(x))swap16_hw(x) ) + +#define swap32(x) \ + ( __builtin_constant_p(x) ? SWAP32_CONST(x) : (typeof(x))swap32_hw(x) ) + +#define swap_odd_even32(x) \ + ( __builtin_constant_p(x) ? SWAP_ODD_EVEN32_CONST(x) : (typeof(x))swap_odd_even32_hw(x) ) + +#define swaw32(x) \ + ( __builtin_constant_p(x) ? SWAW32_CONST(x) : (typeof(x))swaw32_hw(x) ) + + +#ifdef ROCKBOX_LITTLE_ENDIAN +#define letoh16(x) (x) +#define letoh32(x) (x) +#define htole16(x) (x) +#define htole32(x) (x) +#define betoh16(x) swap16(x) +#define betoh32(x) swap32(x) +#define htobe16(x) swap16(x) +#define htobe32(x) swap32(x) +#define swap_odd_even_be32(x) (x) +#define swap_odd_even_le32(x) swap_odd_even32(x) +#else +#define letoh16(x) swap16(x) +#define letoh32(x) swap32(x) +#define htole16(x) swap16(x) +#define htole32(x) swap32(x) +#define betoh16(x) (x) +#define betoh32(x) (x) +#define htobe16(x) (x) +#define htobe32(x) (x) +#define swap_odd_even_be32(x) swap_odd_even32(x) +#define swap_odd_even_le32(x) (x) +#endif + #ifndef BIT_N #define BIT_N(n) (1U << (n)) #endif -- cgit v1.2.3