diff options
Diffstat (limited to 'src/sim/byteswap.hh')
| -rw-r--r-- | src/sim/byteswap.hh | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/src/sim/byteswap.hh b/src/sim/byteswap.hh new file mode 100644 index 000000000..7648b8fcd --- /dev/null +++ b/src/sim/byteswap.hh @@ -0,0 +1,176 @@ +/* + * 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. + * + * Authors: Gabe Black + * Ali Saidi + * Nathan Binkert + */ + +//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 "base/misc.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> +// If this is a linux system, lets used the optimized definitions if they exist. +// If one doesn't exist, we pretty much get what is listed below, so it all +// works out +#include <byteswap.h> +#else +#include <machine/endian.h> +#endif + +#if defined(__APPLE__) +#include <libkern/OSByteOrder.h> +#endif + +//These functions actually perform the swapping for parameters +//of various bit lengths +static inline uint64_t +swap_byte64(uint64_t x) +{ +#if defined(linux) + return bswap_64(x); +#elif defined(__APPLE__) + return OSSwapInt64(x); +#else + 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) ; +#endif +} + +static inline uint32_t +swap_byte32(uint32_t x) +{ +#if defined(linux) + return bswap_32(x); +#elif defined(__APPLE__) + return OSSwapInt32(x); +#else + return (uint32_t)(((uint32_t)(x) & 0xff) << 24 | + ((uint32_t)(x) & 0xff00) << 8 | ((uint32_t)(x) & 0xff0000) >> 8 | + ((uint32_t)(x) & 0xff000000) >> 24); +#endif +} + +static inline uint16_t +swap_byte16(uint16_t x) +{ +#if defined(linux) + return bswap_16(x); +#elif defined(__APPLE__) + return OSSwapInt16(x); +#else + return (uint16_t)(((uint16_t)(x) & 0xff) << 8 | + ((uint16_t)(x) & 0xff00) >> 8); +#endif +} + +// This function lets the compiler figure out how to call the +// swap_byte functions above for different data types. Since the +// sizeof() values are known at compiel time, it should inline to a +// direct call to the right swap_byteNN() function. +template <typename T> +static inline T swap_byte(T x) { + if (sizeof(T) == 8) + return swap_byte64((uint64_t)x); + else if (sizeof(T) == 4) + return swap_byte32((uint32_t)x); + else if (sizeof(T) == 2) + return swap_byte16((uint16_t)x); + else if (sizeof(T) == 1) + return x; + else + panic("Can't byte-swap values larger than 64 bits"); +} + +//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__ |