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Diffstat (limited to 'sim/byteswap.hh')
| -rw-r--r-- | sim/byteswap.hh | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/sim/byteswap.hh b/sim/byteswap.hh new file mode 100644 index 000000000..12d63b6b6 --- /dev/null +++ b/sim/byteswap.hh @@ -0,0 +1,141 @@ +/* + * Copyright (c) 2004 The Regents of The University of Michigan + * 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 copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution; + * neither the name of the copyright holders nor the names of its + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +//The purpose of this file is to provide endainness conversion utility +//functions. Depending on the endianness of the guest system, either +//the LittleEndianGuest or BigEndianGuest namespace is used. + +#ifndef __SIM_BYTE_SWAP_HH__ +#define __SIM_BYTE_SWAP_HH__ + +#include "sim/host.hh" + +// This lets us figure out what the byte order of the host system is +#if defined(linux) +#include <endian.h> +#else +#include <machine/endian.h> +#endif + +//These functions actually perform the swapping for parameters +//of various bit lengths +static inline uint64_t +swap_byte64(uint64_t x) +{ + return (uint64_t)((((uint64_t)(x) & 0xff) << 56) | + ((uint64_t)(x) & 0xff00ULL) << 40 | + ((uint64_t)(x) & 0xff0000ULL) << 24 | + ((uint64_t)(x) & 0xff000000ULL) << 8 | + ((uint64_t)(x) & 0xff00000000ULL) >> 8 | + ((uint64_t)(x) & 0xff0000000000ULL) >> 24 | + ((uint64_t)(x) & 0xff000000000000ULL) >> 40 | + ((uint64_t)(x) & 0xff00000000000000ULL) >> 56) ; +} + +static inline uint32_t +swap_byte32(uint32_t x) +{ + return (uint32_t)(((uint32_t)(x) & 0xff) << 24 | + ((uint32_t)(x) & 0xff00) << 8 | ((uint32_t)(x) & 0xff0000) >> 8 | + ((uint32_t)(x) & 0xff000000) >> 24); + +} + +static inline uint16_t +swap_byte16(uint16_t x) +{ + return (uint16_t)(((uint16_t)(x) & 0xff) << 8 | + ((uint16_t)(x) & 0xff00) >> 8); +} + +//This lets the compiler figure out how to call the swap_byte functions above +//for different data types. +static inline uint64_t swap_byte(uint64_t x) {return swap_byte64(x);} \ +static inline int64_t swap_byte(int64_t x) {return swap_byte64((uint64_t)x);} \ +static inline uint32_t swap_byte(uint32_t x) {return swap_byte32(x);} \ +static inline int32_t swap_byte(int32_t x) {return swap_byte32((uint32_t)x);} \ +static inline uint16_t swap_byte(uint16_t x) {return swap_byte32(x);} \ +static inline int16_t swap_byte(int16_t x) {return swap_byte16((uint16_t)x);} \ +static inline uint8_t swap_byte(uint8_t x) {return x;} \ +static inline int8_t swap_byte(int8_t x) {return x;} \ +static inline double swap_byte(double x) {return swap_byte64((uint64_t)x);} \ +static inline float swap_byte(float x) {return swap_byte32((uint32_t)x);} + +//The conversion functions with fixed endianness on both ends don't need to +//be in a namespace +template <typename T> static inline T betole(T value) {return swap_byte(value);} +template <typename T> static inline T letobe(T value) {return swap_byte(value);} + +//For conversions not involving the guest system, we can define the functions +//conditionally based on the BYTE_ORDER macro and outside of the namespaces +#if BYTE_ORDER == BIG_ENDIAN +template <typename T> static inline T htole(T value) {return swap_byte(value);} +template <typename T> static inline T letoh(T value) {return swap_byte(value);} +template <typename T> static inline T htobe(T value) {return value;} +template <typename T> static inline T betoh(T value) {return value;} +#elif BYTE_ORDER == LITTLE_ENDIAN +template <typename T> static inline T htole(T value) {return value;} +template <typename T> static inline T letoh(T value) {return value;} +template <typename T> static inline T htobe(T value) {return swap_byte(value);} +template <typename T> static inline T betoh(T value) {return swap_byte(value);} +#else + #error Invalid Endianess +#endif + +namespace BigEndianGuest +{ + template <typename T> + static inline T gtole(T value) {return betole(value);} + template <typename T> + static inline T letog(T value) {return letobe(value);} + template <typename T> + static inline T gtobe(T value) {return value;} + template <typename T> + static inline T betog(T value) {return value;} + template <typename T> + static inline T htog(T value) {return htobe(value);} + template <typename T> + static inline T gtoh(T value) {return betoh(value);} +} + +namespace LittleEndianGuest +{ + template <typename T> + static inline T gtole(T value) {return value;} + template <typename T> + static inline T letog(T value) {return value;} + template <typename T> + static inline T gtobe(T value) {return letobe(value);} + template <typename T> + static inline T betog(T value) {return betole(value);} + template <typename T> + static inline T htog(T value) {return htole(value);} + template <typename T> + static inline T gtoh(T value) {return letoh(value);} +} +#endif // __SIM_BYTE_SWAP_HH__ |