1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247
|
/* This file, swapproc.c, contains general utility routines that are */
/* used by other FITSIO routines to swap bytes. */
/* The FITSIO software was written by William Pence at the High Energy */
/* Astrophysic Science Archive Research Center (HEASARC) at the NASA */
/* Goddard Space Flight Center. */
/* The fast SSE2 and SSSE3 functions were provided by Julian Taylor, ESO */
#include <string.h>
#include <stdlib.h>
#include "fitsio2.h"
/* bswap builtin is available since GCC 4.3 */
#if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 3)
#define HAVE_BSWAP
#endif
#ifdef __SSSE3__
#include <tmmintrin.h>
/* swap 16 bytes according to mask, values must be 16 byte aligned */
static inline void swap_ssse3(char * values, __m128i mask)
{
__m128i v = _mm_load_si128((__m128i *)values);
__m128i s = _mm_shuffle_epi8(v, mask);
_mm_store_si128((__m128i*)values, s);
}
#endif
#ifdef __SSE2__
#include <emmintrin.h>
/* swap 8 shorts, values must be 16 byte aligned
* faster than ssse3 variant for shorts */
static inline void swap2_sse2(char * values)
{
__m128i r1 = _mm_load_si128((__m128i *)values);
__m128i r2 = r1;
r1 = _mm_srli_epi16(r1, 8);
r2 = _mm_slli_epi16(r2, 8);
r1 = _mm_or_si128(r1, r2);
_mm_store_si128((__m128i*)values, r1);
}
/* the three shuffles required for 4 and 8 byte variants make
* SSE2 slower than bswap */
/* get number of elements to peel to reach alignment */
static inline size_t get_peel(void * addr, size_t esize, size_t nvals,
size_t alignment)
{
const size_t offset = (size_t)addr % alignment;
size_t peel = offset ? (alignment - offset) / esize : 0;
peel = nvals < peel ? nvals : peel;
return peel;
}
#endif
/*--------------------------------------------------------------------------*/
static void ffswap2_slow(short *svalues, long nvals)
{
register long ii;
unsigned short * usvalues;
usvalues = (unsigned short *) svalues;
for (ii = 0; ii < nvals; ii++)
{
usvalues[ii] = (usvalues[ii]>>8) | (usvalues[ii]<<8);
}
}
/*--------------------------------------------------------------------------*/
#if __SSE2__
void ffswap2(short *svalues, /* IO - pointer to shorts to be swapped */
long nvals) /* I - number of shorts to be swapped */
/*
swap the bytes in the input short integers: ( 0 1 -> 1 0 )
*/
{
if ((long)svalues % 2 != 0) { /* should not happen */
ffswap2_slow(svalues, nvals);
return;
}
long ii;
size_t peel = get_peel((void*)&svalues[0], sizeof(svalues[0]), nvals, 16);
ffswap2_slow(svalues, peel);
for (ii = peel; ii < (nvals - peel - (nvals - peel) % 8); ii+=8) {
swap2_sse2((char*)&svalues[ii]);
}
ffswap2_slow(&svalues[ii], nvals - ii);
}
#else
void ffswap2(short *svalues, /* IO - pointer to shorts to be swapped */
long nvals) /* I - number of shorts to be swapped */
/*
swap the bytes in the input 4-byte integer: ( 0 1 2 3 -> 3 2 1 0 )
*/
{
ffswap2_slow(svalues, nvals);
}
#endif
/*--------------------------------------------------------------------------*/
static void ffswap4_slow(INT32BIT *ivalues, long nvals)
{
register long ii;
#if defined(HAVE_BSWAP)
for (ii = 0; ii < nvals; ii++)
{
ivalues[ii] = __builtin_bswap32(ivalues[ii]);
}
#elif defined(_MSC_VER) && (_MSC_VER >= 1400)
/* intrinsic byte swapping function in Microsoft Visual C++ 8.0 and later */
unsigned int* uivalues = (unsigned int *) ivalues;
/* intrinsic byte swapping function in Microsoft Visual C++ */
for (ii = 0; ii < nvals; ii++)
{
uivalues[ii] = _byteswap_ulong(uivalues[ii]);
}
#else
char *cvalues, tmp;
for (ii = 0; ii < nvals; ii++)
{
cvalues = (char *)&ivalues[ii];
tmp = cvalues[0];
cvalues[0] = cvalues[3];
cvalues[3] = tmp;
tmp = cvalues[1];
cvalues[1] = cvalues[2];
cvalues[2] = tmp;
}
#endif
}
/*--------------------------------------------------------------------------*/
#ifdef __SSSE3__
void ffswap4(INT32BIT *ivalues, /* IO - pointer to INT*4 to be swapped */
long nvals) /* I - number of floats to be swapped */
/*
swap the bytes in the input 4-byte integer: ( 0 1 2 3 -> 3 2 1 0 )
*/
{
if ((long)ivalues % 4 != 0) { /* should not happen */
ffswap4_slow(ivalues, nvals);
return;
}
long ii;
const __m128i cmask4 = _mm_set_epi8(12, 13, 14, 15,
8, 9, 10, 11,
4, 5, 6, 7,
0, 1, 2 ,3);
size_t peel = get_peel((void*)&ivalues[0], sizeof(ivalues[0]), nvals, 16);
ffswap4_slow(ivalues, peel);
for (ii = peel; ii < (nvals - peel - (nvals - peel) % 4); ii+=4) {
swap_ssse3((char*)&ivalues[ii], cmask4);
}
ffswap4_slow(&ivalues[ii], nvals - ii);
}
#else
void ffswap4(INT32BIT *ivalues, /* IO - pointer to INT*4 to be swapped */
long nvals) /* I - number of floats to be swapped */
/*
swap the bytes in the input 4-byte integer: ( 0 1 2 3 -> 3 2 1 0 )
*/
{
ffswap4_slow(ivalues, nvals);
}
#endif
/*--------------------------------------------------------------------------*/
static void ffswap8_slow(double *dvalues, long nvals)
{
register long ii;
#ifdef HAVE_BSWAP
LONGLONG * llvalues = (LONGLONG*)dvalues;
for (ii = 0; ii < nvals; ii++) {
llvalues[ii] = __builtin_bswap64(llvalues[ii]);
}
#elif defined(_MSC_VER) && (_MSC_VER >= 1400)
/* intrinsic byte swapping function in Microsoft Visual C++ 8.0 and later */
unsigned __int64 * llvalues = (unsigned __int64 *) dvalues;
for (ii = 0; ii < nvals; ii++)
{
llvalues[ii] = _byteswap_uint64(llvalues[ii]);
}
#else
register char *cvalues;
register char temp;
cvalues = (char *) dvalues; /* copy the pointer value */
for (ii = 0; ii < nvals*8; ii += 8)
{
temp = cvalues[ii];
cvalues[ii] = cvalues[ii+7];
cvalues[ii+7] = temp;
temp = cvalues[ii+1];
cvalues[ii+1] = cvalues[ii+6];
cvalues[ii+6] = temp;
temp = cvalues[ii+2];
cvalues[ii+2] = cvalues[ii+5];
cvalues[ii+5] = temp;
temp = cvalues[ii+3];
cvalues[ii+3] = cvalues[ii+4];
cvalues[ii+4] = temp;
}
#endif
}
/*--------------------------------------------------------------------------*/
#ifdef __SSSE3__
void ffswap8(double *dvalues, /* IO - pointer to doubles to be swapped */
long nvals) /* I - number of doubles to be swapped */
/*
swap the bytes in the input doubles: ( 01234567 -> 76543210 )
*/
{
if ((long)dvalues % 8 != 0) { /* should not happen on amd64 */
ffswap8_slow(dvalues, nvals);
return;
}
long ii;
const __m128i cmask8 = _mm_set_epi8(8, 9, 10, 11, 12, 13, 14, 15,
0, 1, 2 ,3, 4, 5, 6, 7);
size_t peel = get_peel((void*)&dvalues[0], sizeof(dvalues[0]), nvals, 16);
ffswap8_slow(dvalues, peel);
for (ii = peel; ii < (nvals - peel - (nvals - peel) % 2); ii+=2) {
swap_ssse3((char*)&dvalues[ii], cmask8);
}
ffswap8_slow(&dvalues[ii], nvals - ii);
}
#else
void ffswap8(double *dvalues, /* IO - pointer to doubles to be swapped */
long nvals) /* I - number of doubles to be swapped */
/*
swap the bytes in the input doubles: ( 01234567 -> 76543210 )
*/
{
ffswap8_slow(dvalues, nvals);
}
#endif
|