ocaml/byterun/reverse.h

89 lines
5.4 KiB
C

/***********************************************************************/
/* */
/* Objective Caml */
/* */
/* Xavier Leroy, projet Cristal, INRIA Rocquencourt */
/* */
/* Copyright 1996 Institut National de Recherche en Informatique et */
/* en Automatique. All rights reserved. This file is distributed */
/* under the terms of the GNU Library General Public License, with */
/* the special exception on linking described in file ../LICENSE. */
/* */
/***********************************************************************/
/* $Id$ */
/* Swap byte-order in 16, 32, and 64-bit integers or floats */
#ifndef _reverse_
#define _reverse_
#define Reverse_16(dst,src) { \
char * _p, * _q; \
char _a; \
_p = (char *) (src); \
_q = (char *) (dst); \
_a = _p[0]; \
_q[0] = _p[1]; \
_q[1] = _a; \
}
#define Reverse_32(dst,src) { \
char * _p, * _q; \
char _a, _b; \
_p = (char *) (src); \
_q = (char *) (dst); \
_a = _p[0]; \
_b = _p[1]; \
_q[0] = _p[3]; \
_q[1] = _p[2]; \
_q[3] = _a; \
_q[2] = _b; \
}
#define Reverse_64(dst,src) { \
char * _p, * _q; \
char _a, _b; \
_p = (char *) (src); \
_q = (char *) (dst); \
_a = _p[0]; \
_b = _p[1]; \
_q[0] = _p[7]; \
_q[1] = _p[6]; \
_q[7] = _a; \
_q[6] = _b; \
_a = _p[2]; \
_b = _p[3]; \
_q[2] = _p[5]; \
_q[3] = _p[4]; \
_q[5] = _a; \
_q[4] = _b; \
}
#define Perm_index(perm,i) ((perm >> (i * 4)) & 0xF)
#define Permute_64(dst,perm_dst,src,perm_src) { \
char * _p; \
char _a, _b, _c, _d, _e, _f, _g, _h; \
_p = (char *) (src); \
_a = _p[Perm_index(perm_src, 0)]; \
_b = _p[Perm_index(perm_src, 1)]; \
_c = _p[Perm_index(perm_src, 2)]; \
_d = _p[Perm_index(perm_src, 3)]; \
_e = _p[Perm_index(perm_src, 4)]; \
_f = _p[Perm_index(perm_src, 5)]; \
_g = _p[Perm_index(perm_src, 6)]; \
_h = _p[Perm_index(perm_src, 7)]; \
_p = (char *) (dst); \
_p[Perm_index(perm_dst, 0)] = _a; \
_p[Perm_index(perm_dst, 1)] = _b; \
_p[Perm_index(perm_dst, 2)] = _c; \
_p[Perm_index(perm_dst, 3)] = _d; \
_p[Perm_index(perm_dst, 4)] = _e; \
_p[Perm_index(perm_dst, 5)] = _f; \
_p[Perm_index(perm_dst, 6)] = _g; \
_p[Perm_index(perm_dst, 7)] = _h; \
}
#endif /* _reverse_ */