isl_seq.c

   1 /*
   2  * Copyright 2008-2009 Katholieke Universiteit Leuven
   3  * Copyright 2011      INRIA Saclay
   4  *
   5  * Use of this software is governed by the MIT license
   6  *
   7  * Written by Sven Verdoolaege, K.U.Leuven, Departement
   8  * Computerwetenschappen, Celestijnenlaan 200A, B-3001 Leuven, Belgium
   9  */
  10
  11 #include <isl_ctx_private.h>
  12 #include <isl_seq.h>
  13
  14 void isl_seq_clr(isl_int *p, unsigned len)
  15 {
  16         int i;
  17         for (i = 0; i < len; ++i)
  18                 isl_int_set_si(p[i], 0);
  19 }
  20
  21 void isl_seq_set_si(isl_int *p, int v, unsigned len)
  22 {
  23         int i;
  24         for (i = 0; i < len; ++i)
  25                 isl_int_set_si(p[i], v);
  26 }
  27
  28 void isl_seq_set(isl_int *p, isl_int v, unsigned len)
  29 {
  30         int i;
  31         for (i = 0; i < len; ++i)
  32                 isl_int_set(p[i], v);
  33 }
  34
  35 void isl_seq_neg(isl_int *dst, isl_int *src, unsigned len)
  36 {
  37         int i;
  38         for (i = 0; i < len; ++i)
  39                 isl_int_neg(dst[i], src[i]);
  40 }
  41
  42 void isl_seq_cpy(isl_int *dst, isl_int *src, unsigned len)
  43 {
  44         int i;
  45         for (i = 0; i < len; ++i)
  46                 isl_int_set(dst[i], src[i]);
  47 }
  48
  49 /* Subtract the sequence "src" from the sequence "dst",
  50  * both of length "len".
  51  */
  52 void isl_seq_sub(isl_int *dst, isl_int *src, unsigned len)
  53 {
  54         int i;
  55
  56         for (i = 0; i < len; ++i)
  57                 isl_int_sub(dst[i], dst[i], src[i]);
  58 }
  59
  60 void isl_seq_submul(isl_int *dst, isl_int f, isl_int *src, unsigned len)
  61 {
  62         int i;
  63         for (i = 0; i < len; ++i)
  64                 isl_int_submul(dst[i], f, src[i]);
  65 }
  66
  67 void isl_seq_addmul(isl_int *dst, isl_int f, isl_int *src, unsigned len)
  68 {
  69         int i;
  70         for (i = 0; i < len; ++i)
  71                 isl_int_addmul(dst[i], f, src[i]);
  72 }
  73
  74 void isl_seq_swp_or_cpy(isl_int *dst, isl_int *src, unsigned len)
  75 {
  76         int i;
  77         for (i = 0; i < len; ++i)
  78                 isl_int_swap_or_set(dst[i], src[i]);
  79 }
  80
  81 void isl_seq_scale(isl_int *dst, isl_int *src, isl_int m, unsigned len)
  82 {
  83         int i;
  84         for (i = 0; i < len; ++i)
  85                 isl_int_mul(dst[i], src[i], m);
  86 }
  87
  88 void isl_seq_scale_down(isl_int *dst, isl_int *src, isl_int m, unsigned len)
  89 {
  90         int i;
  91         for (i = 0; i < len; ++i)
  92                 isl_int_divexact(dst[i], src[i], m);
  93 }
  94
  95 void isl_seq_cdiv_q(isl_int *dst, isl_int *src, isl_int m, unsigned len)
  96 {
  97         int i;
  98         for (i = 0; i < len; ++i)
  99                 isl_int_cdiv_q(dst[i], src[i], m);
 100 }
 101
 102 void isl_seq_fdiv_q(isl_int *dst, isl_int *src, isl_int m, unsigned len)
 103 {
 104         int i;
 105         for (i = 0; i < len; ++i)
 106                 isl_int_fdiv_q(dst[i], src[i], m);
 107 }
 108
 109 void isl_seq_fdiv_r(isl_int *dst, isl_int *src, isl_int m, unsigned len)
 110 {
 111         int i;
 112         for (i = 0; i < len; ++i)
 113                 isl_int_fdiv_r(dst[i], src[i], m);
 114 }
 115
 116 void isl_seq_combine(isl_int *dst, isl_int m1, isl_int *src1,
 117                         isl_int m2, isl_int *src2, unsigned len)
 118 {
 119         int i;
 120         isl_int tmp;
 121
 122         if (dst == src1 && isl_int_is_one(m1)) {
 123                 if (isl_int_is_zero(m2))
 124                         return;
 125                 for (i = 0; i < len; ++i)
 126                         isl_int_addmul(src1[i], m2, src2[i]);
 127                 return;
 128         }
 129
 130         isl_int_init(tmp);
 131         for (i = 0; i < len; ++i) {
 132                 isl_int_mul(tmp, m1, src1[i]);
 133                 isl_int_addmul(tmp, m2, src2[i]);
 134                 isl_int_set(dst[i], tmp);
 135         }
 136         isl_int_clear(tmp);
 137 }
 138
 139 /* Eliminate element "pos" from "dst" using "src".
 140  * In particular, let d = dst[pos] and s = src[pos], then
 141  * dst is replaced by (|s| dst - sgn(s)d src)/gcd(s,d),
 142  * such that dst[pos] is zero after the elimination.
 143  * If "m" is not NULL, then *m is multiplied by |s|/gcd(s,d).
 144  * That is, it is multiplied by the same factor as "dst".
 145  */
 146 void isl_seq_elim(isl_int *dst, isl_int *src, unsigned pos, unsigned len,
 147                   isl_int *m)
 148 {
 149         isl_int a;
 150         isl_int b;
 151
 152         if (isl_int_is_zero(dst[pos]))
 153                 return;
 154
 155         isl_int_init(a);
 156         isl_int_init(b);
 157
 158         isl_int_gcd(a, src[pos], dst[pos]);
 159         isl_int_divexact(b, dst[pos], a);
 160         if (isl_int_is_pos(src[pos]))
 161                 isl_int_neg(b, b);
 162         isl_int_divexact(a, src[pos], a);
 163         isl_int_abs(a, a);
 164         isl_seq_combine(dst, a, dst, b, src, len);
 165
 166         if (m)
 167                 isl_int_mul(*m, *m, a);
 168
 169         isl_int_clear(a);
 170         isl_int_clear(b);
 171 }
 172
 173 int isl_seq_eq(isl_int *p1, isl_int *p2, unsigned len)
 174 {
 175         int i;
 176         for (i = 0; i < len; ++i)
 177                 if (isl_int_ne(p1[i], p2[i]))
 178                         return 0;
 179         return 1;
 180 }
 181
 182 int isl_seq_cmp(isl_int *p1, isl_int *p2, unsigned len)
 183 {
 184         int i;
 185         int cmp;
 186         for (i = 0; i < len; ++i)
 187                 if ((cmp = isl_int_cmp(p1[i], p2[i])) != 0)
 188                         return cmp;
 189         return 0;
 190 }
 191
 192 int isl_seq_is_neg(isl_int *p1, isl_int *p2, unsigned len)
 193 {
 194         int i;
 195
 196         for (i = 0; i < len; ++i) {
 197                 if (isl_int_abs_ne(p1[i], p2[i]))
 198                         return 0;
 199                 if (isl_int_is_zero(p1[i]))
 200                         continue;
 201                 if (isl_int_eq(p1[i], p2[i]))
 202                         return 0;
 203         }
 204         return 1;
 205 }
 206
 207 int isl_seq_first_non_zero(isl_int *p, unsigned len)
 208 {
 209         int i;
 210
 211         for (i = 0; i < len; ++i)
 212                 if (!isl_int_is_zero(p[i]))
 213                         return i;
 214         return -1;
 215 }
 216
 217 int isl_seq_last_non_zero(isl_int *p, unsigned len)
 218 {
 219         int i;
 220
 221         for (i = len - 1; i >= 0; --i)
 222                 if (!isl_int_is_zero(p[i]))
 223                         return i;
 224         return -1;
 225 }
 226
 227 void isl_seq_abs_max(isl_int *p, unsigned len, isl_int *max)
 228 {
 229         int i;
 230
 231         isl_int_set_si(*max, 0);
 232
 233         for (i = 0; i < len; ++i)
 234                 if (isl_int_abs_gt(p[i], *max))
 235                         isl_int_abs(*max, p[i]);
 236 }
 237
 238 int isl_seq_abs_min_non_zero(isl_int *p, unsigned len)
 239 {
 240         int i, min = isl_seq_first_non_zero(p, len);
 241         if (min < 0)
 242                 return -1;
 243         for (i = min + 1; i < len; ++i) {
 244                 if (isl_int_is_zero(p[i]))
 245                         continue;
 246                 if (isl_int_abs_lt(p[i], p[min]))
 247                         min = i;
 248         }
 249         return min;
 250 }
 251
 252 void isl_seq_gcd(isl_int *p, unsigned len, isl_int *gcd)
 253 {
 254         int i, min = isl_seq_abs_min_non_zero(p, len);
 255
 256         if (min < 0) {
 257                 isl_int_set_si(*gcd, 0);
 258                 return;
 259         }
 260         isl_int_abs(*gcd, p[min]);
 261         for (i = 0; isl_int_cmp_si(*gcd, 1) > 0 && i < len; ++i) {
 262                 if (i == min)
 263                         continue;
 264                 if (isl_int_is_zero(p[i]))
 265                         continue;
 266                 isl_int_gcd(*gcd, *gcd, p[i]);
 267         }
 268 }
 269
 270 void isl_seq_normalize(struct isl_ctx *ctx, isl_int *p, unsigned len)
 271 {
 272         if (len == 0)
 273                 return;
 274         isl_seq_gcd(p, len, &ctx->normalize_gcd);
 275         if (!isl_int_is_zero(ctx->normalize_gcd) &&
 276             !isl_int_is_one(ctx->normalize_gcd))
 277                 isl_seq_scale_down(p, p, ctx->normalize_gcd, len);
 278 }
 279
 280 void isl_seq_lcm(isl_int *p, unsigned len, isl_int *lcm)
 281 {
 282         int i;
 283
 284         if (len == 0) {
 285                 isl_int_set_si(*lcm, 1);
 286                 return;
 287         }
 288         isl_int_set(*lcm, p[0]);
 289         for (i = 1; i < len; ++i)
 290                 isl_int_lcm(*lcm, *lcm, p[i]);
 291 }
 292
 293 void isl_seq_inner_product(isl_int *p1, isl_int *p2, unsigned len,
 294                            isl_int *prod)
 295 {
 296         int i;
 297         if (len == 0) {
 298                 isl_int_set_si(*prod, 0);
 299                 return;
 300         }
 301         isl_int_mul(*prod, p1[0], p2[0]);
 302         for (i = 1; i < len; ++i)
 303                 isl_int_addmul(*prod, p1[i], p2[i]);
 304 }
 305
 306 uint32_t isl_seq_hash(isl_int *p, unsigned len, uint32_t hash)
 307 {
 308         int i;
 309         for (i = 0; i < len; ++i) {
 310                 if (isl_int_is_zero(p[i]))
 311                         continue;
 312                 hash *= 16777619;
 313                 hash ^= (i & 0xFF);
 314                 hash = isl_int_hash(p[i], hash);
 315         }
 316         return hash;
 317 }
 318
 319 /* Given two affine expressions "p" of length p_len (including the
 320  * denominator and the constant term) and "subs" of length subs_len,
 321  * plug in "subs" for the variable at position "pos".
 322  * The variables of "subs" and "p" are assumed to match up to subs_len,
 323  * but "p" may have additional variables.
 324  * "v" is an initialized isl_int that can be used internally.
 325  *
 326  * In particular, if "p" represents the expression
 327  *
 328  *      (a i + g)/m
 329  *
 330  * with i the variable at position "pos" and "subs" represents the expression
 331  *
 332  *      f/d
 333  *
 334  * then the result represents the expression
 335  *
 336  *      (a f + d g)/(m d)
 337  *
 338  */
 339 void isl_seq_substitute(isl_int *p, int pos, isl_int *subs,
 340         int p_len, int subs_len, isl_int v)
 341 {
 342         isl_int_set(v, p[1 + pos]);
 343         isl_int_set_si(p[1 + pos], 0);
 344         isl_seq_combine(p + 1, subs[0], p + 1, v, subs + 1, subs_len - 1);
 345         isl_seq_scale(p + subs_len, p + subs_len, subs[0], p_len - subs_len);
 346         isl_int_mul(p[0], p[0], subs[0]);
 347 }
 348
 349 uint32_t isl_seq_get_hash(isl_int *p, unsigned len)
 350 {
 351         uint32_t hash = isl_hash_init();
 352
 353         return isl_seq_hash(p, len, hash);
 354 }
 355
 356 uint32_t isl_seq_get_hash_bits(isl_int *p, unsigned len, unsigned bits)
 357 {
 358         uint32_t hash;
 359
 360         hash = isl_seq_get_hash(p, len);
 361         return isl_hash_bits(hash, bits);
 362 }
 363
 364 void isl_seq_dump(isl_int *p, unsigned len)
 365 {
 366         int i;
 367
 368         for (i = 0; i < len; ++i) {
 369                 if (i)
 370                         fprintf(stderr, " ");
 371                 isl_int_print(stderr, p[i], 0);
 372         }
 373         fprintf(stderr, "\n");
 374 }