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[mLib] / bits.h
1 /* -*-c-*-
2 *
3 * $Id: bits.h,v 1.9 2001/01/20 12:05:20 mdw Exp $
4 *
5 * Portable bit-level manipulation macros
6 *
7 * (c) 1998 Straylight/Edgeware
8 */
9
10 /*----- Licensing notice --------------------------------------------------*
11 *
12 * This file is part of the mLib utilities library.
13 *
14 * mLib is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU Library General Public License as
16 * published by the Free Software Foundation; either version 2 of the
17 * License, or (at your option) any later version.
18 *
19 * mLib is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU Library General Public License for more details.
23 *
24 * You should have received a copy of the GNU Library General Public
25 * License along with mLib; if not, write to the Free
26 * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
27 * MA 02111-1307, USA.
28 */
29
30 /*----- Revision history --------------------------------------------------*
31 *
32 * $Log: bits.h,v $
33 * Revision 1.9 2001/01/20 12:05:20 mdw
34 * New hack for storing 64-bit numbers in tables.
35 *
36 * Revision 1.8 2000/10/08 11:06:30 mdw
37 * Shut later versions of GCC up about use of @long long@.
38 *
39 * Revision 1.7 2000/07/22 09:48:26 mdw
40 * Added macros for reading 64-bit values.
41 *
42 * Revision 1.6 2000/07/16 12:28:28 mdw
43 * Add 64-bit support, with faked arithmetic on 32-bit hosts.
44 *
45 * Revision 1.5 2000/06/17 10:36:06 mdw
46 * Support for 24-bit types.
47 *
48 * Revision 1.4 1999/12/10 23:42:04 mdw
49 * Change header file guard names.
50 *
51 * Revision 1.3 1999/06/20 23:31:52 mdw
52 * More portability enhancements.
53 *
54 * Revision 1.2 1999/06/17 00:12:46 mdw
55 * Improve portability for shift and rotate macros.
56 *
57 * Revision 1.1 1999/06/01 09:46:19 mdw
58 * New addition: bit manipulation macros.
59 *
60 */
61
62 #ifndef MLIB_BITS_H
63 #define MLIB_BITS_H
64
65 #ifdef __cplusplus
66 extern "C" {
67 #endif
68
69 /*----- Header files ------------------------------------------------------*/
70
71 #include <limits.h>
72 #include <stddef.h>
73 #if __STDC_VERSION__ >= 199900l
74 # include <stdint.h>
75 #endif
76
77 /*----- Decide on some types ----------------------------------------------*/
78
79 /* --- Make GNU C shut up --- */
80
81 #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 91)
82 # define MLIB_BITS_EXTENSION __extension__
83 #else
84 # define MLIB_BITS_EXTENSION
85 #endif
86
87 /* --- Decide on a 32-bit type --- *
88 *
89 * I want a type which is capable of expressing 32-bit numbers. Because some
90 * implementations have 64-bit @long@s (infinitely preferable to the abortion
91 * that is @long long@), using @unsigned long@ regardless is wasteful. So,
92 * if @int@ appears to be good enough, then I'll go with that.
93 */
94
95 #if UINT_MAX >= 0xffffffffu
96 typedef unsigned int uint32;
97 #else
98 typedef unsigned long uint32;
99 #endif
100
101 /* --- Decide on a 64-bit type --- *
102 *
103 * The test is quite subtle. Think about it. Note that (at least on my
104 * machine), the 32-bit macros are *much* faster than GCC's @long long@
105 * support.
106 */
107
108 #if defined(ULONG_LONG_MAX) && !defined(ULLONG_MAX)
109 # define ULLONG_MAX ULONG_LONG_MAX
110 #endif
111
112 #if UINT_MAX >> 31 > 0xffffffff
113 # define HAVE_UINT64
114 typedef unsigned int uint64;
115 #elif ULONG_MAX >> 31 > 0xffffffff
116 # define HAVE_UINT64
117 typedef unsigned long uint64;
118 #elif defined(ULLONG_MAX)
119 # define HAVE_UINT64
120 MLIB_BITS_EXTENSION typedef unsigned long long uint64;
121 #endif
122
123 #ifdef DEBUG64
124 # undef HAVE_UINT64
125 #endif
126
127 #ifdef HAVE_UINT64
128 typedef struct { uint64 i; } kludge64;
129 #else
130 typedef struct { uint32 hi, lo; } kludge64;
131 #endif
132
133 /* --- Decide on a 24-bit type --- */
134
135 #if UINT_MAX >= 0x00ffffffu
136 typedef unsigned int uint24;
137 #else
138 typedef unsigned long uint24;
139 #endif
140
141 /* --- Decide on 16-bit and 8-bit types --- *
142 *
143 * This is more for brevity than anything else.
144 */
145
146 typedef unsigned short uint16;
147 typedef unsigned char octet;
148
149 /* --- WARNING! --- *
150 *
151 * Never lose sight of the fact that the above types may be wider than the
152 * names suggest. Some architectures have 32-bit @short@s for example.
153 */
154
155 /*----- Macros ------------------------------------------------------------*/
156
157 /* --- Useful masks --- */
158
159 #define MASK8 0xffu
160 #define MASK16 0xffffu
161 #define MASK24 0xffffffu
162 #define MASK32 0xffffffffu
163
164 #ifdef HAVE_UINT64
165 # define MASK64 MLIB_BITS_EXTENSION 0xffffffffffffffffu
166 #endif
167
168 /* --- Type coercions --- */
169
170 #define U8(x) ((octet)((x) & MASK8))
171 #define U16(x) ((uint16)((x) & MASK16))
172 #define U24(x) ((uint24)((x) & MASK24))
173 #define U32(x) ((uint32)((x) & MASK32))
174
175 #ifdef HAVE_UINT64
176 # define U64(x) ((uint64)(x) & MASK64)
177 # define U64_(d, x) ((d).i = U64(x).i)
178 #else
179 # define U64_(d, x) ((d).hi = U32((x).hi), (d).lo = U32((x).lo))
180 #endif
181
182 /* --- Safe shifting macros --- */
183
184 #define LSL8(v, s) U8(U8(v) << ((s) & 7u))
185 #define LSR8(v, s) U8(U8(v) >> ((s) & 7u))
186 #define LSL16(v, s) U16(U16(v) << ((s) & 15u))
187 #define LSR16(v, s) U16(U16(v) >> ((s) & 15u))
188 #define LSL24(v, s) U24(U24(v) << ((s) % 24u))
189 #define LSR24(v, s) U24(U24(v) >> ((s) % 24u))
190 #define LSL32(v, s) U32(U32(v) << ((s) & 31u))
191 #define LSR32(v, s) U32(U32(v) >> ((s) & 31u))
192
193 #ifdef HAVE_UINT64
194 # define LSL64(v, s) U64(U64(v) << ((s) & 63u))
195 # define LSR64(v, s) U64(U64(v) >> ((s) & 63u))
196 # define LSL64_(d, v, s) ((d).i = LSL64((v).i, (s)))
197 # define LSR64_(d, v, s) ((d).i = LSR64((v).i, (s)))
198 #else
199 # define LSL64_(d, v, s) do { \
200 unsigned _s = (s) & 63u; \
201 uint32 _l = (v).lo, _h = (v).hi; \
202 kludge64 *_d = &(d); \
203 if (_s >= 32) { \
204 _d->hi = LSL32(_l, _s - 32u); \
205 _d->lo = 0; \
206 } else if (!_s) { \
207 _d->lo = _l; \
208 _d->hi = _h; \
209 } else { \
210 _d->hi = LSL32(_h, _s) | LSR32(_l, 32u - _s); \
211 _d->lo = LSL32(_l, _s); \
212 } \
213 } while (0)
214 # define LSR64_(d, v, s) do { \
215 unsigned _s = (s) & 63u; \
216 uint32 _l = (v).lo, _h = (v).hi; \
217 kludge64 *_d = &(d); \
218 if (_s >= 32) { \
219 _d->lo = LSR32(_h, _s - 32u); \
220 _d->hi = 0; \
221 } else if (!_s) { \
222 _d->lo = _l; \
223 _d->hi = _h; \
224 } else { \
225 _d->lo = LSR32(_l, _s) | LSL32(_h, 32u - _s); \
226 _d->hi = LSR32(_h, _s); \
227 } \
228 } while (0)
229 #endif
230
231 /* --- Rotation macros --- */
232
233 #define ROL8(v, s) (LSL8((v), (s)) | (LSR8((v), 8u - (s))))
234 #define ROR8(v, s) (LSR8((v), (s)) | (LSL8((v), 8u - (s))))
235 #define ROL16(v, s) (LSL16((v), (s)) | (LSR16((v), 16u - (s))))
236 #define ROR16(v, s) (LSR16((v), (s)) | (LSL16((v), 16u - (s))))
237 #define ROL24(v, s) (LSL24((v), (s)) | (LSR24((v), 24u - (s))))
238 #define ROR24(v, s) (LSR24((v), (s)) | (LSL24((v), 24u - (s))))
239 #define ROL32(v, s) (LSL32((v), (s)) | (LSR32((v), 32u - (s))))
240 #define ROR32(v, s) (LSR32((v), (s)) | (LSL32((v), 32u - (s))))
241
242 #ifdef HAVE_UINT64
243 # define ROL64(v, s) (LSL64((v), (s)) | (LSR64((v), 64u - (s))))
244 # define ROR64(v, s) (LSR64((v), (s)) | (LSL64((v), 64u - (s))))
245 # define ROL64_(d, v, s) ((d).i = ROL64((v).i, (s)))
246 # define ROR64_(d, v, s) ((d).i = ROR64((v).i, (s)))
247 #else
248 # define ROL64_(d, v, s) do { \
249 unsigned _s = (s) & 63u; \
250 uint32 _l = (v).lo, _h = (v).hi; \
251 kludge64 *_d = &(d); \
252 if (_s >= 32) { \
253 _d->hi = LSL32(_l, _s - 32u) | LSR32(_h, 64u - _s); \
254 _d->lo = LSL32(_h, _s - 32u) | LSR32(_l, 64u - _s); \
255 } else if (!_s) { \
256 _d->lo = _l; \
257 _d->hi = _h; \
258 } else { \
259 _d->hi = LSL32(_h, _s) | LSR32(_l, 32u - _s); \
260 _d->lo = LSL32(_l, _s) | LSR32(_h, 32u - _s); \
261 } \
262 } while (0)
263 # define ROR64_(d, v, s) do { \
264 unsigned _s = (s) & 63u; \
265 uint32 _l = (v).lo, _h = (v).hi; \
266 kludge64 *_d = &(d); \
267 if (_s >= 32) { \
268 _d->hi = LSR32(_l, _s - 32u) | LSL32(_h, 64u - _s); \
269 _d->lo = LSR32(_h, _s - 32u) | LSL32(_l, 64u - _s); \
270 } else if (!_s) { \
271 _d->lo = _l; \
272 _d->hi = _h; \
273 } else { \
274 _d->hi = LSR32(_h, _s) | LSL32(_l, 32u - _s); \
275 _d->lo = LSR32(_l, _s) | LSL32(_h, 32u - _s); \
276 } \
277 } while (0)
278 #endif
279
280 /* --- Storage and retrieval --- */
281
282 #define GETBYTE(p, o) (((octet *)(p))[o] & MASK8)
283 #define PUTBYTE(p, o, v) (((octet *)(p))[o] = U8((v)))
284
285 #define LOAD8(p) (GETBYTE((p), 0))
286 #define STORE8(p, v) (PUTBYTE((p), 0, (v)))
287
288 #define LOAD16_B(p) \
289 (((uint16)GETBYTE((p), 0) << 8) | \
290 ((uint16)GETBYTE((p), 1) << 0))
291 #define LOAD16_L(p) \
292 (((uint16)GETBYTE((p), 0) << 0) | \
293 ((uint16)GETBYTE((p), 1) << 8))
294 #define LOAD16(p) LOAD16_B((p))
295
296 #define STORE16_B(p, v) \
297 (PUTBYTE((p), 0, (uint16)(v) >> 8), \
298 PUTBYTE((p), 1, (uint16)(v) >> 0))
299 #define STORE16_L(p, v) \
300 (PUTBYTE((p), 0, (uint16)(v) >> 0), \
301 PUTBYTE((p), 1, (uint16)(v) >> 8))
302 #define STORE16(p, v) STORE16_B((p), (v))
303
304 #define LOAD24_B(p) \
305 (((uint24)GETBYTE((p), 0) << 16) | \
306 ((uint24)GETBYTE((p), 1) << 8) | \
307 ((uint24)GETBYTE((p), 2) << 0))
308 #define LOAD24_L(p) \
309 (((uint24)GETBYTE((p), 0) << 0) | \
310 ((uint24)GETBYTE((p), 1) << 8) | \
311 ((uint24)GETBYTE((p), 2) << 16))
312 #define LOAD24(p) LOAD24_B((p))
313
314 #define STORE24_B(p, v) \
315 (PUTBYTE((p), 0, (uint24)(v) >> 16), \
316 PUTBYTE((p), 1, (uint24)(v) >> 8), \
317 PUTBYTE((p), 2, (uint24)(v) >> 0))
318 #define STORE24_L(p, v) \
319 (PUTBYTE((p), 0, (uint24)(v) >> 0), \
320 PUTBYTE((p), 1, (uint24)(v) >> 8), \
321 PUTBYTE((p), 2, (uint24)(v) >> 16))
322 #define STORE24(p, v) STORE24_B((p), (v))
323
324 #define LOAD32_B(p) \
325 (((uint32)GETBYTE((p), 0) << 24) | \
326 ((uint32)GETBYTE((p), 1) << 16) | \
327 ((uint32)GETBYTE((p), 2) << 8) | \
328 ((uint32)GETBYTE((p), 3) << 0))
329 #define LOAD32_L(p) \
330 (((uint32)GETBYTE((p), 0) << 0) | \
331 ((uint32)GETBYTE((p), 1) << 8) | \
332 ((uint32)GETBYTE((p), 2) << 16) | \
333 ((uint32)GETBYTE((p), 3) << 24))
334 #define LOAD32(p) LOAD32_B((p))
335
336 #define STORE32_B(p, v) \
337 (PUTBYTE((p), 0, (uint32)(v) >> 24), \
338 PUTBYTE((p), 1, (uint32)(v) >> 16), \
339 PUTBYTE((p), 2, (uint32)(v) >> 8), \
340 PUTBYTE((p), 3, (uint32)(v) >> 0))
341 #define STORE32_L(p, v) \
342 (PUTBYTE((p), 0, (uint32)(v) >> 0), \
343 PUTBYTE((p), 1, (uint32)(v) >> 8), \
344 PUTBYTE((p), 2, (uint32)(v) >> 16), \
345 PUTBYTE((p), 3, (uint32)(v) >> 24))
346 #define STORE32(p, v) STORE32_B((p), (v))
347
348 #ifdef HAVE_UINT64
349
350 # define LOAD64_B(p) \
351 (((uint64)GETBYTE((p), 0) << 56) | \
352 ((uint64)GETBYTE((p), 1) << 48) | \
353 ((uint64)GETBYTE((p), 2) << 40) | \
354 ((uint64)GETBYTE((p), 3) << 32) | \
355 ((uint64)GETBYTE((p), 4) << 24) | \
356 ((uint64)GETBYTE((p), 5) << 16) | \
357 ((uint64)GETBYTE((p), 6) << 8) | \
358 ((uint64)GETBYTE((p), 7) << 0))
359 # define LOAD64_L(p) \
360 (((uint64)GETBYTE((p), 0) << 0) | \
361 ((uint64)GETBYTE((p), 1) << 8) | \
362 ((uint64)GETBYTE((p), 2) << 16) | \
363 ((uint64)GETBYTE((p), 3) << 24) | \
364 ((uint64)GETBYTE((p), 4) << 32) | \
365 ((uint64)GETBYTE((p), 5) << 40) | \
366 ((uint64)GETBYTE((p), 6) << 48) | \
367 ((uint64)GETBYTE((p), 7) << 56))
368 # define LOAD64(p) LOAD64_B((p))
369 # define LOAD64_B_(d, p) ((d).i = LOAD64_B((p)))
370 # define LOAD64_L_(d, p) ((d).i = LOAD64_L((p)))
371 # define LOAD64_(d, p) LOAD64_B_((d), (p))
372
373 # define STORE64_B(p, v) \
374 (PUTBYTE((p), 0, (uint64)(v) >> 56), \
375 PUTBYTE((p), 1, (uint64)(v) >> 48), \
376 PUTBYTE((p), 2, (uint64)(v) >> 40), \
377 PUTBYTE((p), 3, (uint64)(v) >> 32), \
378 PUTBYTE((p), 4, (uint64)(v) >> 24), \
379 PUTBYTE((p), 5, (uint64)(v) >> 16), \
380 PUTBYTE((p), 6, (uint64)(v) >> 8), \
381 PUTBYTE((p), 7, (uint64)(v) >> 0))
382 # define STORE64_L(p, v) \
383 (PUTBYTE((p), 0, (uint64)(v) >> 0), \
384 PUTBYTE((p), 1, (uint64)(v) >> 8), \
385 PUTBYTE((p), 2, (uint64)(v) >> 16), \
386 PUTBYTE((p), 3, (uint64)(v) >> 24), \
387 PUTBYTE((p), 4, (uint64)(v) >> 32), \
388 PUTBYTE((p), 5, (uint64)(v) >> 40), \
389 PUTBYTE((p), 6, (uint64)(v) >> 48), \
390 PUTBYTE((p), 7, (uint64)(v) >> 56))
391 # define STORE64(p, v) STORE64_B((p), (v))
392 # define STORE64_B_(p, v) STORE64_B((p), (v).i)
393 # define STORE64_L_(p, v) STORE64_L((p), (v).i)
394 # define STORE64_(p, v) STORE64_B_((p), (v))
395
396 #else
397
398 # define LOAD64_B_(d, p) \
399 ((d).hi = LOAD32_B((octet *)(p) + 0), \
400 (d).lo = LOAD32_B((octet *)(p) + 4))
401 # define LOAD64_L_(d, p) \
402 ((d).lo = LOAD32_L((octet *)(p) + 0), \
403 (d).hi = LOAD32_L((octet *)(p) + 4))
404 # define LOAD64_(d, p) LOAD64_B_((d), (p))
405
406 # define STORE64_B_(p, v) \
407 (STORE32_B((octet *)(p) + 0, (v).hi), \
408 STORE32_B((octet *)(p) + 4, (v).lo))
409 # define STORE64_L_(p, v) \
410 (STORE32_L((octet *)(p) + 0, (v).lo), \
411 STORE32_L((octet *)(p) + 4, (v).hi))
412 # define STORE64_(p, v) STORE64_B_((p), (v))
413
414 #endif
415
416 /* --- Other operations on 64-bit integers --- */
417
418 #ifdef HAVE_UINT64
419 # define SET64(d, h, l) ((d).i = (U64((h)) << 32) | U64((l)))
420 # define ASSIGN64(d, x) ((d).i = U64((x)))
421 # define HI64(x) U32((x).i >> 32)
422 # define LO64(x) U32((x).i)
423 # define GET64(t, x) ((t)(x).i)
424 #else
425 # define SET64(d, h, l) ((d).hi = U32(h), (d).lo = U32(l))
426 # define ASSIGN64(d, x) \
427 ((d).hi = ((x & ~MASK32) >> 16) >> 16, (d).lo = U32(x))
428 # define HI64(x) U32((x).hi)
429 # define LO64(x) U32((x).lo)
430 # define GET64(t, x) (((((t)HI64(x) << 16) << 16) & ~MASK32) | (t)LO64(x))
431 #endif
432
433 #ifdef HAVE_UINT64
434 # define AND64(d, x, y) ((d).i = (x).i & (y).i)
435 # define OR64(d, x, y) ((d).i = (x).i | (y).i)
436 # define XOR64(d, x, y) ((d).i = (x).i ^ (y).i)
437 # define CPL64(d, x) ((d).i = ~(x).i)
438 # define ADD64(d, x, y) ((d).i = (x).i + (y).i)
439 # define SUB64(d, x, y) ((d).i = (x).i - (y).i)
440 # define CMP64(x, op, y) ((x).i op (y).i)
441 # define ZERO64(x) ((x) == 0)
442 #else
443 # define AND64(d, x, y) ((d).lo = (x).lo & (y).lo, (d).hi = (x).hi & (y).hi)
444 # define OR64(d, x, y) ((d).lo = (x).lo | (y).lo, (d).hi = (x).hi | (y).hi)
445 # define XOR64(d, x, y) ((d).lo = (x).lo ^ (y).lo, (d).hi = (x).hi ^ (y).hi)
446 # define CPL64(d, x) ((d).lo = ~(x).lo, (d).hi = ~(x).hi)
447 # define ADD64(d, x, y) do { \
448 uint32 _x = U32((x).lo + (y).lo); \
449 (d).hi = (x).hi + (y).hi + (_x < (x).lo); \
450 (d).lo = _x; \
451 } while (0)
452 # define SUB64(d, x, y) do { \
453 uint32 _x = U32((x).lo - (y).lo); \
454 (d).hi = (x).hi - (y).hi - (_x > (x).lo); \
455 (d).lo = _x; \
456 } while (0)
457 # define CMP64(x, op, y) \
458 ((x).hi == (y).hi ? (x).lo op (y).lo : (x).hi op (y).hi)
459 # define ZERO64(x) ((x).lo == 0 && (x).hi == 0)
460 #endif
461
462 /* --- Storing integers in tables --- */
463
464 #ifdef HAVE_UINT64
465 # define X64(x, y) { 0x##x##y }
466 #else
467 # define X64(x, y) { 0x##x, 0x##y }
468 #endif
469
470 /*----- That's all, folks -------------------------------------------------*/
471
472 #ifdef __cplusplus
473 }
474 #endif
475
476 #endif
mLib utilities library