isl_basic_map_eliminate: reuse isl_basic_map_check_range
[isl.git] / isl_mat.c
blob839ad3fecf7d5f8f4783dac82fb9d404edf914f6
1 /*
2 * Copyright 2008-2009 Katholieke Universiteit Leuven
3 * Copyright 2010 INRIA Saclay
4 * Copyright 2014 Ecole Normale Superieure
5 * Copyright 2017 Sven Verdoolaege
7 * Use of this software is governed by the MIT license
9 * Written by Sven Verdoolaege, K.U.Leuven, Departement
10 * Computerwetenschappen, Celestijnenlaan 200A, B-3001 Leuven, Belgium
11 * and INRIA Saclay - Ile-de-France, Parc Club Orsay Universite,
12 * ZAC des vignes, 4 rue Jacques Monod, 91893 Orsay, France
13 * and Ecole Normale Superieure, 45 rue d'Ulm, 75230 Paris, France
16 #include <isl_ctx_private.h>
17 #include <isl_map_private.h>
18 #include <isl/space.h>
19 #include <isl_seq.h>
20 #include <isl_mat_private.h>
21 #include <isl_vec_private.h>
22 #include <isl_space_private.h>
23 #include <isl_val_private.h>
25 isl_ctx *isl_mat_get_ctx(__isl_keep isl_mat *mat)
27 return mat ? mat->ctx : NULL;
30 /* Return a hash value that digests "mat".
32 uint32_t isl_mat_get_hash(__isl_keep isl_mat *mat)
34 int i;
35 uint32_t hash;
37 if (!mat)
38 return 0;
40 hash = isl_hash_init();
41 isl_hash_byte(hash, mat->n_row & 0xFF);
42 isl_hash_byte(hash, mat->n_col & 0xFF);
43 for (i = 0; i < mat->n_row; ++i) {
44 uint32_t row_hash;
46 row_hash = isl_seq_get_hash(mat->row[i], mat->n_col);
47 isl_hash_hash(hash, row_hash);
50 return hash;
53 struct isl_mat *isl_mat_alloc(struct isl_ctx *ctx,
54 unsigned n_row, unsigned n_col)
56 int i;
57 struct isl_mat *mat;
59 mat = isl_alloc_type(ctx, struct isl_mat);
60 if (!mat)
61 return NULL;
63 mat->row = NULL;
64 mat->block = isl_blk_alloc(ctx, n_row * n_col);
65 if (isl_blk_is_error(mat->block))
66 goto error;
67 mat->row = isl_alloc_array(ctx, isl_int *, n_row);
68 if (n_row && !mat->row)
69 goto error;
71 for (i = 0; i < n_row; ++i)
72 mat->row[i] = mat->block.data + i * n_col;
74 mat->ctx = ctx;
75 isl_ctx_ref(ctx);
76 mat->ref = 1;
77 mat->n_row = n_row;
78 mat->n_col = n_col;
79 mat->max_col = n_col;
80 mat->flags = 0;
82 return mat;
83 error:
84 isl_blk_free(ctx, mat->block);
85 free(mat);
86 return NULL;
89 struct isl_mat *isl_mat_extend(struct isl_mat *mat,
90 unsigned n_row, unsigned n_col)
92 int i;
93 isl_int *old;
94 isl_int **row;
96 if (!mat)
97 return NULL;
99 if (mat->max_col >= n_col && mat->n_row >= n_row) {
100 if (mat->n_col < n_col)
101 mat->n_col = n_col;
102 return mat;
105 if (mat->max_col < n_col) {
106 struct isl_mat *new_mat;
108 if (n_row < mat->n_row)
109 n_row = mat->n_row;
110 new_mat = isl_mat_alloc(mat->ctx, n_row, n_col);
111 if (!new_mat)
112 goto error;
113 for (i = 0; i < mat->n_row; ++i)
114 isl_seq_cpy(new_mat->row[i], mat->row[i], mat->n_col);
115 isl_mat_free(mat);
116 return new_mat;
119 mat = isl_mat_cow(mat);
120 if (!mat)
121 goto error;
123 old = mat->block.data;
124 mat->block = isl_blk_extend(mat->ctx, mat->block, n_row * mat->max_col);
125 if (isl_blk_is_error(mat->block))
126 goto error;
127 row = isl_realloc_array(mat->ctx, mat->row, isl_int *, n_row);
128 if (n_row && !row)
129 goto error;
130 mat->row = row;
132 for (i = 0; i < mat->n_row; ++i)
133 mat->row[i] = mat->block.data + (mat->row[i] - old);
134 for (i = mat->n_row; i < n_row; ++i)
135 mat->row[i] = mat->block.data + i * mat->max_col;
136 mat->n_row = n_row;
137 if (mat->n_col < n_col)
138 mat->n_col = n_col;
140 return mat;
141 error:
142 isl_mat_free(mat);
143 return NULL;
146 __isl_give isl_mat *isl_mat_sub_alloc6(isl_ctx *ctx, isl_int **row,
147 unsigned first_row, unsigned n_row, unsigned first_col, unsigned n_col)
149 int i;
150 struct isl_mat *mat;
152 mat = isl_alloc_type(ctx, struct isl_mat);
153 if (!mat)
154 return NULL;
155 mat->row = isl_alloc_array(ctx, isl_int *, n_row);
156 if (n_row && !mat->row)
157 goto error;
158 for (i = 0; i < n_row; ++i)
159 mat->row[i] = row[first_row+i] + first_col;
160 mat->ctx = ctx;
161 isl_ctx_ref(ctx);
162 mat->ref = 1;
163 mat->n_row = n_row;
164 mat->n_col = n_col;
165 mat->block = isl_blk_empty();
166 mat->flags = ISL_MAT_BORROWED;
167 return mat;
168 error:
169 free(mat);
170 return NULL;
173 __isl_give isl_mat *isl_mat_sub_alloc(__isl_keep isl_mat *mat,
174 unsigned first_row, unsigned n_row, unsigned first_col, unsigned n_col)
176 if (!mat)
177 return NULL;
178 return isl_mat_sub_alloc6(mat->ctx, mat->row, first_row, n_row,
179 first_col, n_col);
182 void isl_mat_sub_copy(struct isl_ctx *ctx, isl_int **dst, isl_int **src,
183 unsigned n_row, unsigned dst_col, unsigned src_col, unsigned n_col)
185 int i;
187 for (i = 0; i < n_row; ++i)
188 isl_seq_cpy(dst[i]+dst_col, src[i]+src_col, n_col);
191 void isl_mat_sub_neg(struct isl_ctx *ctx, isl_int **dst, isl_int **src,
192 unsigned n_row, unsigned dst_col, unsigned src_col, unsigned n_col)
194 int i;
196 for (i = 0; i < n_row; ++i)
197 isl_seq_neg(dst[i]+dst_col, src[i]+src_col, n_col);
200 __isl_give isl_mat *isl_mat_copy(__isl_keep isl_mat *mat)
202 if (!mat)
203 return NULL;
205 mat->ref++;
206 return mat;
209 __isl_give isl_mat *isl_mat_dup(__isl_keep isl_mat *mat)
211 int i;
212 struct isl_mat *mat2;
214 if (!mat)
215 return NULL;
216 mat2 = isl_mat_alloc(mat->ctx, mat->n_row, mat->n_col);
217 if (!mat2)
218 return NULL;
219 for (i = 0; i < mat->n_row; ++i)
220 isl_seq_cpy(mat2->row[i], mat->row[i], mat->n_col);
221 return mat2;
224 __isl_give isl_mat *isl_mat_cow(__isl_take isl_mat *mat)
226 struct isl_mat *mat2;
227 if (!mat)
228 return NULL;
230 if (mat->ref == 1 && !ISL_F_ISSET(mat, ISL_MAT_BORROWED))
231 return mat;
233 mat2 = isl_mat_dup(mat);
234 isl_mat_free(mat);
235 return mat2;
238 __isl_null isl_mat *isl_mat_free(__isl_take isl_mat *mat)
240 if (!mat)
241 return NULL;
243 if (--mat->ref > 0)
244 return NULL;
246 if (!ISL_F_ISSET(mat, ISL_MAT_BORROWED))
247 isl_blk_free(mat->ctx, mat->block);
248 isl_ctx_deref(mat->ctx);
249 free(mat->row);
250 free(mat);
252 return NULL;
255 int isl_mat_rows(__isl_keep isl_mat *mat)
257 return mat ? mat->n_row : -1;
260 int isl_mat_cols(__isl_keep isl_mat *mat)
262 return mat ? mat->n_col : -1;
265 /* Check that "col" is a valid column position for "mat".
267 static isl_stat check_col(__isl_keep isl_mat *mat, int col)
269 if (!mat)
270 return isl_stat_error;
271 if (col < 0 || col >= mat->n_col)
272 isl_die(isl_mat_get_ctx(mat), isl_error_invalid,
273 "column out of range", return isl_stat_error);
274 return isl_stat_ok;
277 /* Check that "row" is a valid row position for "mat".
279 static isl_stat check_row(__isl_keep isl_mat *mat, int row)
281 if (!mat)
282 return isl_stat_error;
283 if (row < 0 || row >= mat->n_row)
284 isl_die(isl_mat_get_ctx(mat), isl_error_invalid,
285 "row out of range", return isl_stat_error);
286 return isl_stat_ok;
289 /* Check that there are "n" columns starting at position "first" in "mat".
291 static isl_stat check_col_range(__isl_keep isl_mat *mat, unsigned first,
292 unsigned n)
294 if (!mat)
295 return isl_stat_error;
296 if (first + n > mat->n_col || first + n < first)
297 isl_die(isl_mat_get_ctx(mat), isl_error_invalid,
298 "column position or range out of bounds",
299 return isl_stat_error);
300 return isl_stat_ok;
303 /* Check that there are "n" rows starting at position "first" in "mat".
305 static isl_stat check_row_range(__isl_keep isl_mat *mat, unsigned first,
306 unsigned n)
308 if (!mat)
309 return isl_stat_error;
310 if (first + n > mat->n_row || first + n < first)
311 isl_die(isl_mat_get_ctx(mat), isl_error_invalid,
312 "row position or range out of bounds",
313 return isl_stat_error);
314 return isl_stat_ok;
317 int isl_mat_get_element(__isl_keep isl_mat *mat, int row, int col, isl_int *v)
319 if (check_row(mat, row) < 0)
320 return -1;
321 if (check_col(mat, col) < 0)
322 return -1;
323 isl_int_set(*v, mat->row[row][col]);
324 return 0;
327 /* Extract the element at row "row", oolumn "col" of "mat".
329 __isl_give isl_val *isl_mat_get_element_val(__isl_keep isl_mat *mat,
330 int row, int col)
332 isl_ctx *ctx;
334 if (check_row(mat, row) < 0)
335 return NULL;
336 if (check_col(mat, col) < 0)
337 return NULL;
338 ctx = isl_mat_get_ctx(mat);
339 return isl_val_int_from_isl_int(ctx, mat->row[row][col]);
342 __isl_give isl_mat *isl_mat_set_element(__isl_take isl_mat *mat,
343 int row, int col, isl_int v)
345 mat = isl_mat_cow(mat);
346 if (check_row(mat, row) < 0)
347 return isl_mat_free(mat);
348 if (check_col(mat, col) < 0)
349 return isl_mat_free(mat);
350 isl_int_set(mat->row[row][col], v);
351 return mat;
354 __isl_give isl_mat *isl_mat_set_element_si(__isl_take isl_mat *mat,
355 int row, int col, int v)
357 mat = isl_mat_cow(mat);
358 if (check_row(mat, row) < 0)
359 return isl_mat_free(mat);
360 if (check_col(mat, col) < 0)
361 return isl_mat_free(mat);
362 isl_int_set_si(mat->row[row][col], v);
363 return mat;
366 /* Replace the element at row "row", column "col" of "mat" by "v".
368 __isl_give isl_mat *isl_mat_set_element_val(__isl_take isl_mat *mat,
369 int row, int col, __isl_take isl_val *v)
371 if (!v)
372 return isl_mat_free(mat);
373 if (!isl_val_is_int(v))
374 isl_die(isl_val_get_ctx(v), isl_error_invalid,
375 "expecting integer value", goto error);
376 mat = isl_mat_set_element(mat, row, col, v->n);
377 isl_val_free(v);
378 return mat;
379 error:
380 isl_val_free(v);
381 return isl_mat_free(mat);
384 __isl_give isl_mat *isl_mat_diag(isl_ctx *ctx, unsigned n_row, isl_int d)
386 int i;
387 struct isl_mat *mat;
389 mat = isl_mat_alloc(ctx, n_row, n_row);
390 if (!mat)
391 return NULL;
392 for (i = 0; i < n_row; ++i) {
393 isl_seq_clr(mat->row[i], i);
394 isl_int_set(mat->row[i][i], d);
395 isl_seq_clr(mat->row[i]+i+1, n_row-(i+1));
398 return mat;
401 /* Create an "n_row" by "n_col" matrix with zero elements.
403 __isl_give isl_mat *isl_mat_zero(isl_ctx *ctx, unsigned n_row, unsigned n_col)
405 int i;
406 isl_mat *mat;
408 mat = isl_mat_alloc(ctx, n_row, n_col);
409 if (!mat)
410 return NULL;
411 for (i = 0; i < n_row; ++i)
412 isl_seq_clr(mat->row[i], n_col);
414 return mat;
417 __isl_give isl_mat *isl_mat_identity(isl_ctx *ctx, unsigned n_row)
419 if (!ctx)
420 return NULL;
421 return isl_mat_diag(ctx, n_row, ctx->one);
424 /* Is "mat" a (possibly scaled) identity matrix?
426 int isl_mat_is_scaled_identity(__isl_keep isl_mat *mat)
428 int i;
430 if (!mat)
431 return -1;
432 if (mat->n_row != mat->n_col)
433 return 0;
435 for (i = 0; i < mat->n_row; ++i) {
436 if (isl_seq_first_non_zero(mat->row[i], i) != -1)
437 return 0;
438 if (isl_int_ne(mat->row[0][0], mat->row[i][i]))
439 return 0;
440 if (isl_seq_first_non_zero(mat->row[i] + i + 1,
441 mat->n_col - (i + 1)) != -1)
442 return 0;
445 return 1;
448 __isl_give isl_vec *isl_mat_vec_product(__isl_take isl_mat *mat,
449 __isl_take isl_vec *vec)
451 int i;
452 struct isl_vec *prod;
454 if (!mat || !vec)
455 goto error;
457 isl_assert(mat->ctx, mat->n_col == vec->size, goto error);
459 prod = isl_vec_alloc(mat->ctx, mat->n_row);
460 if (!prod)
461 goto error;
463 for (i = 0; i < prod->size; ++i)
464 isl_seq_inner_product(mat->row[i], vec->el, vec->size,
465 &prod->block.data[i]);
466 isl_mat_free(mat);
467 isl_vec_free(vec);
468 return prod;
469 error:
470 isl_mat_free(mat);
471 isl_vec_free(vec);
472 return NULL;
475 __isl_give isl_vec *isl_mat_vec_inverse_product(__isl_take isl_mat *mat,
476 __isl_take isl_vec *vec)
478 struct isl_mat *vec_mat;
479 int i;
481 if (!mat || !vec)
482 goto error;
483 vec_mat = isl_mat_alloc(vec->ctx, vec->size, 1);
484 if (!vec_mat)
485 goto error;
486 for (i = 0; i < vec->size; ++i)
487 isl_int_set(vec_mat->row[i][0], vec->el[i]);
488 vec_mat = isl_mat_inverse_product(mat, vec_mat);
489 isl_vec_free(vec);
490 if (!vec_mat)
491 return NULL;
492 vec = isl_vec_alloc(vec_mat->ctx, vec_mat->n_row);
493 if (vec)
494 for (i = 0; i < vec->size; ++i)
495 isl_int_set(vec->el[i], vec_mat->row[i][0]);
496 isl_mat_free(vec_mat);
497 return vec;
498 error:
499 isl_mat_free(mat);
500 isl_vec_free(vec);
501 return NULL;
504 __isl_give isl_vec *isl_vec_mat_product(__isl_take isl_vec *vec,
505 __isl_take isl_mat *mat)
507 int i, j;
508 struct isl_vec *prod;
510 if (!mat || !vec)
511 goto error;
513 isl_assert(mat->ctx, mat->n_row == vec->size, goto error);
515 prod = isl_vec_alloc(mat->ctx, mat->n_col);
516 if (!prod)
517 goto error;
519 for (i = 0; i < prod->size; ++i) {
520 isl_int_set_si(prod->el[i], 0);
521 for (j = 0; j < vec->size; ++j)
522 isl_int_addmul(prod->el[i], vec->el[j], mat->row[j][i]);
524 isl_mat_free(mat);
525 isl_vec_free(vec);
526 return prod;
527 error:
528 isl_mat_free(mat);
529 isl_vec_free(vec);
530 return NULL;
533 __isl_give isl_mat *isl_mat_aff_direct_sum(__isl_take isl_mat *left,
534 __isl_take isl_mat *right)
536 int i;
537 struct isl_mat *sum;
539 if (!left || !right)
540 goto error;
542 isl_assert(left->ctx, left->n_row == right->n_row, goto error);
543 isl_assert(left->ctx, left->n_row >= 1, goto error);
544 isl_assert(left->ctx, left->n_col >= 1, goto error);
545 isl_assert(left->ctx, right->n_col >= 1, goto error);
546 isl_assert(left->ctx,
547 isl_seq_first_non_zero(left->row[0]+1, left->n_col-1) == -1,
548 goto error);
549 isl_assert(left->ctx,
550 isl_seq_first_non_zero(right->row[0]+1, right->n_col-1) == -1,
551 goto error);
553 sum = isl_mat_alloc(left->ctx, left->n_row, left->n_col + right->n_col - 1);
554 if (!sum)
555 goto error;
556 isl_int_lcm(sum->row[0][0], left->row[0][0], right->row[0][0]);
557 isl_int_divexact(left->row[0][0], sum->row[0][0], left->row[0][0]);
558 isl_int_divexact(right->row[0][0], sum->row[0][0], right->row[0][0]);
560 isl_seq_clr(sum->row[0]+1, sum->n_col-1);
561 for (i = 1; i < sum->n_row; ++i) {
562 isl_int_mul(sum->row[i][0], left->row[0][0], left->row[i][0]);
563 isl_int_addmul(sum->row[i][0],
564 right->row[0][0], right->row[i][0]);
565 isl_seq_scale(sum->row[i]+1, left->row[i]+1, left->row[0][0],
566 left->n_col-1);
567 isl_seq_scale(sum->row[i]+left->n_col,
568 right->row[i]+1, right->row[0][0],
569 right->n_col-1);
572 isl_int_divexact(left->row[0][0], sum->row[0][0], left->row[0][0]);
573 isl_int_divexact(right->row[0][0], sum->row[0][0], right->row[0][0]);
574 isl_mat_free(left);
575 isl_mat_free(right);
576 return sum;
577 error:
578 isl_mat_free(left);
579 isl_mat_free(right);
580 return NULL;
583 static void exchange(struct isl_mat *M, struct isl_mat **U,
584 struct isl_mat **Q, unsigned row, unsigned i, unsigned j)
586 int r;
587 for (r = row; r < M->n_row; ++r)
588 isl_int_swap(M->row[r][i], M->row[r][j]);
589 if (U) {
590 for (r = 0; r < (*U)->n_row; ++r)
591 isl_int_swap((*U)->row[r][i], (*U)->row[r][j]);
593 if (Q)
594 isl_mat_swap_rows(*Q, i, j);
597 static void subtract(struct isl_mat *M, struct isl_mat **U,
598 struct isl_mat **Q, unsigned row, unsigned i, unsigned j, isl_int m)
600 int r;
601 for (r = row; r < M->n_row; ++r)
602 isl_int_submul(M->row[r][j], m, M->row[r][i]);
603 if (U) {
604 for (r = 0; r < (*U)->n_row; ++r)
605 isl_int_submul((*U)->row[r][j], m, (*U)->row[r][i]);
607 if (Q) {
608 for (r = 0; r < (*Q)->n_col; ++r)
609 isl_int_addmul((*Q)->row[i][r], m, (*Q)->row[j][r]);
613 static void oppose(struct isl_mat *M, struct isl_mat **U,
614 struct isl_mat **Q, unsigned row, unsigned col)
616 int r;
617 for (r = row; r < M->n_row; ++r)
618 isl_int_neg(M->row[r][col], M->row[r][col]);
619 if (U) {
620 for (r = 0; r < (*U)->n_row; ++r)
621 isl_int_neg((*U)->row[r][col], (*U)->row[r][col]);
623 if (Q)
624 isl_seq_neg((*Q)->row[col], (*Q)->row[col], (*Q)->n_col);
627 /* Given matrix M, compute
629 * M U = H
630 * M = H Q
632 * with U and Q unimodular matrices and H a matrix in column echelon form
633 * such that on each echelon row the entries in the non-echelon column
634 * are non-negative (if neg == 0) or non-positive (if neg == 1)
635 * and strictly smaller (in absolute value) than the entries in the echelon
636 * column.
637 * If U or Q are NULL, then these matrices are not computed.
639 __isl_give isl_mat *isl_mat_left_hermite(__isl_take isl_mat *M, int neg,
640 __isl_give isl_mat **U, __isl_give isl_mat **Q)
642 isl_int c;
643 int row, col;
645 if (U)
646 *U = NULL;
647 if (Q)
648 *Q = NULL;
649 if (!M)
650 goto error;
651 M = isl_mat_cow(M);
652 if (!M)
653 goto error;
654 if (U) {
655 *U = isl_mat_identity(M->ctx, M->n_col);
656 if (!*U)
657 goto error;
659 if (Q) {
660 *Q = isl_mat_identity(M->ctx, M->n_col);
661 if (!*Q)
662 goto error;
665 col = 0;
666 isl_int_init(c);
667 for (row = 0; row < M->n_row; ++row) {
668 int first, i, off;
669 first = isl_seq_abs_min_non_zero(M->row[row]+col, M->n_col-col);
670 if (first == -1)
671 continue;
672 first += col;
673 if (first != col)
674 exchange(M, U, Q, row, first, col);
675 if (isl_int_is_neg(M->row[row][col]))
676 oppose(M, U, Q, row, col);
677 first = col+1;
678 while ((off = isl_seq_first_non_zero(M->row[row]+first,
679 M->n_col-first)) != -1) {
680 first += off;
681 isl_int_fdiv_q(c, M->row[row][first], M->row[row][col]);
682 subtract(M, U, Q, row, col, first, c);
683 if (!isl_int_is_zero(M->row[row][first]))
684 exchange(M, U, Q, row, first, col);
685 else
686 ++first;
688 for (i = 0; i < col; ++i) {
689 if (isl_int_is_zero(M->row[row][i]))
690 continue;
691 if (neg)
692 isl_int_cdiv_q(c, M->row[row][i], M->row[row][col]);
693 else
694 isl_int_fdiv_q(c, M->row[row][i], M->row[row][col]);
695 if (isl_int_is_zero(c))
696 continue;
697 subtract(M, U, Q, row, col, i, c);
699 ++col;
701 isl_int_clear(c);
703 return M;
704 error:
705 if (Q) {
706 isl_mat_free(*Q);
707 *Q = NULL;
709 if (U) {
710 isl_mat_free(*U);
711 *U = NULL;
713 isl_mat_free(M);
714 return NULL;
717 /* Use row "row" of "mat" to eliminate column "col" from all other rows.
719 static __isl_give isl_mat *eliminate(__isl_take isl_mat *mat, int row, int col)
721 int k, nr, nc;
722 isl_ctx *ctx;
724 if (!mat)
725 return NULL;
727 ctx = isl_mat_get_ctx(mat);
728 nr = isl_mat_rows(mat);
729 nc = isl_mat_cols(mat);
731 for (k = 0; k < nr; ++k) {
732 if (k == row)
733 continue;
734 if (isl_int_is_zero(mat->row[k][col]))
735 continue;
736 mat = isl_mat_cow(mat);
737 if (!mat)
738 return NULL;
739 isl_seq_elim(mat->row[k], mat->row[row], col, nc, NULL);
740 isl_seq_normalize(ctx, mat->row[k], nc);
743 return mat;
746 /* Perform Gaussian elimination on the rows of "mat", but start
747 * from the final row and the final column.
748 * Any zero rows that result from the elimination are removed.
750 * In particular, for each column from last to first,
751 * look for the last row with a non-zero coefficient in that column,
752 * move it last (but before other rows moved last in previous steps) and
753 * use it to eliminate the column from the other rows.
755 __isl_give isl_mat *isl_mat_reverse_gauss(__isl_take isl_mat *mat)
757 int k, row, last, nr, nc;
759 if (!mat)
760 return NULL;
762 nr = isl_mat_rows(mat);
763 nc = isl_mat_cols(mat);
765 last = nc - 1;
766 for (row = nr - 1; row >= 0; --row) {
767 for (; last >= 0; --last) {
768 for (k = row; k >= 0; --k)
769 if (!isl_int_is_zero(mat->row[k][last]))
770 break;
771 if (k >= 0)
772 break;
774 if (last < 0)
775 break;
776 if (k != row)
777 mat = isl_mat_swap_rows(mat, k, row);
778 if (!mat)
779 return NULL;
780 if (isl_int_is_neg(mat->row[row][last]))
781 mat = isl_mat_row_neg(mat, row);
782 mat = eliminate(mat, row, last);
783 if (!mat)
784 return NULL;
786 mat = isl_mat_drop_rows(mat, 0, row + 1);
788 return mat;
791 /* Negate the lexicographically negative rows of "mat" such that
792 * all rows in the result are lexicographically non-negative.
794 __isl_give isl_mat *isl_mat_lexnonneg_rows(__isl_take isl_mat *mat)
796 int i, nr, nc;
798 if (!mat)
799 return NULL;
801 nr = isl_mat_rows(mat);
802 nc = isl_mat_cols(mat);
804 for (i = 0; i < nr; ++i) {
805 int pos;
807 pos = isl_seq_first_non_zero(mat->row[i], nc);
808 if (pos < 0)
809 continue;
810 if (isl_int_is_nonneg(mat->row[i][pos]))
811 continue;
812 mat = isl_mat_row_neg(mat, i);
813 if (!mat)
814 return NULL;
817 return mat;
820 /* Given a matrix "H" is column echelon form, what is the first
821 * zero column? That is how many initial columns are non-zero?
822 * Start looking at column "first_col" and only consider
823 * the columns to be of size "n_row".
824 * "H" is assumed to be non-NULL.
826 * Since "H" is in column echelon form, the first non-zero entry
827 * in a column is always in a later position compared to the previous column.
829 static int hermite_first_zero_col(__isl_keep isl_mat *H, int first_col,
830 int n_row)
832 int row, col;
834 for (col = first_col, row = 0; col < H->n_col; ++col) {
835 for (; row < n_row; ++row)
836 if (!isl_int_is_zero(H->row[row][col]))
837 break;
838 if (row == n_row)
839 return col;
842 return H->n_col;
845 /* Return the rank of "mat", or -1 in case of error.
847 int isl_mat_rank(__isl_keep isl_mat *mat)
849 int rank;
850 isl_mat *H;
852 H = isl_mat_left_hermite(isl_mat_copy(mat), 0, NULL, NULL);
853 if (!H)
854 return -1;
856 rank = hermite_first_zero_col(H, 0, H->n_row);
857 isl_mat_free(H);
859 return rank;
862 __isl_give isl_mat *isl_mat_right_kernel(__isl_take isl_mat *mat)
864 int rank;
865 struct isl_mat *U = NULL;
866 struct isl_mat *K;
868 mat = isl_mat_left_hermite(mat, 0, &U, NULL);
869 if (!mat || !U)
870 goto error;
872 rank = hermite_first_zero_col(mat, 0, mat->n_row);
873 K = isl_mat_alloc(U->ctx, U->n_row, U->n_col - rank);
874 if (!K)
875 goto error;
876 isl_mat_sub_copy(K->ctx, K->row, U->row, U->n_row, 0, rank, U->n_col-rank);
877 isl_mat_free(mat);
878 isl_mat_free(U);
879 return K;
880 error:
881 isl_mat_free(mat);
882 isl_mat_free(U);
883 return NULL;
886 __isl_give isl_mat *isl_mat_lin_to_aff(__isl_take isl_mat *mat)
888 int i;
889 struct isl_mat *mat2;
891 if (!mat)
892 return NULL;
893 mat2 = isl_mat_alloc(mat->ctx, 1+mat->n_row, 1+mat->n_col);
894 if (!mat2)
895 goto error;
896 isl_int_set_si(mat2->row[0][0], 1);
897 isl_seq_clr(mat2->row[0]+1, mat->n_col);
898 for (i = 0; i < mat->n_row; ++i) {
899 isl_int_set_si(mat2->row[1+i][0], 0);
900 isl_seq_cpy(mat2->row[1+i]+1, mat->row[i], mat->n_col);
902 isl_mat_free(mat);
903 return mat2;
904 error:
905 isl_mat_free(mat);
906 return NULL;
909 /* Given two matrices M1 and M2, return the block matrix
911 * [ M1 0 ]
912 * [ 0 M2 ]
914 __isl_give isl_mat *isl_mat_diagonal(__isl_take isl_mat *mat1,
915 __isl_take isl_mat *mat2)
917 int i;
918 isl_mat *mat;
920 if (!mat1 || !mat2)
921 goto error;
923 mat = isl_mat_alloc(mat1->ctx, mat1->n_row + mat2->n_row,
924 mat1->n_col + mat2->n_col);
925 if (!mat)
926 goto error;
927 for (i = 0; i < mat1->n_row; ++i) {
928 isl_seq_cpy(mat->row[i], mat1->row[i], mat1->n_col);
929 isl_seq_clr(mat->row[i] + mat1->n_col, mat2->n_col);
931 for (i = 0; i < mat2->n_row; ++i) {
932 isl_seq_clr(mat->row[mat1->n_row + i], mat1->n_col);
933 isl_seq_cpy(mat->row[mat1->n_row + i] + mat1->n_col,
934 mat2->row[i], mat2->n_col);
936 isl_mat_free(mat1);
937 isl_mat_free(mat2);
938 return mat;
939 error:
940 isl_mat_free(mat1);
941 isl_mat_free(mat2);
942 return NULL;
945 static int row_first_non_zero(isl_int **row, unsigned n_row, unsigned col)
947 int i;
949 for (i = 0; i < n_row; ++i)
950 if (!isl_int_is_zero(row[i][col]))
951 return i;
952 return -1;
955 static int row_abs_min_non_zero(isl_int **row, unsigned n_row, unsigned col)
957 int i, min = row_first_non_zero(row, n_row, col);
958 if (min < 0)
959 return -1;
960 for (i = min + 1; i < n_row; ++i) {
961 if (isl_int_is_zero(row[i][col]))
962 continue;
963 if (isl_int_abs_lt(row[i][col], row[min][col]))
964 min = i;
966 return min;
969 static isl_stat inv_exchange(__isl_keep isl_mat **left,
970 __isl_keep isl_mat **right, unsigned i, unsigned j)
972 *left = isl_mat_swap_rows(*left, i, j);
973 *right = isl_mat_swap_rows(*right, i, j);
975 if (!*left || !*right)
976 return isl_stat_error;
977 return isl_stat_ok;
980 static void inv_oppose(
981 struct isl_mat *left, struct isl_mat *right, unsigned row)
983 isl_seq_neg(left->row[row]+row, left->row[row]+row, left->n_col-row);
984 isl_seq_neg(right->row[row], right->row[row], right->n_col);
987 static void inv_subtract(struct isl_mat *left, struct isl_mat *right,
988 unsigned row, unsigned i, isl_int m)
990 isl_int_neg(m, m);
991 isl_seq_combine(left->row[i]+row,
992 left->ctx->one, left->row[i]+row,
993 m, left->row[row]+row,
994 left->n_col-row);
995 isl_seq_combine(right->row[i], right->ctx->one, right->row[i],
996 m, right->row[row], right->n_col);
999 /* Compute inv(left)*right
1001 __isl_give isl_mat *isl_mat_inverse_product(__isl_take isl_mat *left,
1002 __isl_take isl_mat *right)
1004 int row;
1005 isl_int a, b;
1007 if (!left || !right)
1008 goto error;
1010 isl_assert(left->ctx, left->n_row == left->n_col, goto error);
1011 isl_assert(left->ctx, left->n_row == right->n_row, goto error);
1013 if (left->n_row == 0) {
1014 isl_mat_free(left);
1015 return right;
1018 left = isl_mat_cow(left);
1019 right = isl_mat_cow(right);
1020 if (!left || !right)
1021 goto error;
1023 isl_int_init(a);
1024 isl_int_init(b);
1025 for (row = 0; row < left->n_row; ++row) {
1026 int pivot, first, i, off;
1027 pivot = row_abs_min_non_zero(left->row+row, left->n_row-row, row);
1028 if (pivot < 0) {
1029 isl_int_clear(a);
1030 isl_int_clear(b);
1031 isl_assert(left->ctx, pivot >= 0, goto error);
1033 pivot += row;
1034 if (pivot != row)
1035 if (inv_exchange(&left, &right, pivot, row) < 0)
1036 goto error;
1037 if (isl_int_is_neg(left->row[row][row]))
1038 inv_oppose(left, right, row);
1039 first = row+1;
1040 while ((off = row_first_non_zero(left->row+first,
1041 left->n_row-first, row)) != -1) {
1042 first += off;
1043 isl_int_fdiv_q(a, left->row[first][row],
1044 left->row[row][row]);
1045 inv_subtract(left, right, row, first, a);
1046 if (!isl_int_is_zero(left->row[first][row])) {
1047 if (inv_exchange(&left, &right, row, first) < 0)
1048 goto error;
1049 } else {
1050 ++first;
1053 for (i = 0; i < row; ++i) {
1054 if (isl_int_is_zero(left->row[i][row]))
1055 continue;
1056 isl_int_gcd(a, left->row[row][row], left->row[i][row]);
1057 isl_int_divexact(b, left->row[i][row], a);
1058 isl_int_divexact(a, left->row[row][row], a);
1059 isl_int_neg(b, b);
1060 isl_seq_combine(left->row[i] + i,
1061 a, left->row[i] + i,
1062 b, left->row[row] + i,
1063 left->n_col - i);
1064 isl_seq_combine(right->row[i], a, right->row[i],
1065 b, right->row[row], right->n_col);
1068 isl_int_clear(b);
1070 isl_int_set(a, left->row[0][0]);
1071 for (row = 1; row < left->n_row; ++row)
1072 isl_int_lcm(a, a, left->row[row][row]);
1073 if (isl_int_is_zero(a)){
1074 isl_int_clear(a);
1075 isl_assert(left->ctx, 0, goto error);
1077 for (row = 0; row < left->n_row; ++row) {
1078 isl_int_divexact(left->row[row][row], a, left->row[row][row]);
1079 if (isl_int_is_one(left->row[row][row]))
1080 continue;
1081 isl_seq_scale(right->row[row], right->row[row],
1082 left->row[row][row], right->n_col);
1084 isl_int_clear(a);
1086 isl_mat_free(left);
1087 return right;
1088 error:
1089 isl_mat_free(left);
1090 isl_mat_free(right);
1091 return NULL;
1094 void isl_mat_col_scale(struct isl_mat *mat, unsigned col, isl_int m)
1096 int i;
1098 for (i = 0; i < mat->n_row; ++i)
1099 isl_int_mul(mat->row[i][col], mat->row[i][col], m);
1102 void isl_mat_col_combine(struct isl_mat *mat, unsigned dst,
1103 isl_int m1, unsigned src1, isl_int m2, unsigned src2)
1105 int i;
1106 isl_int tmp;
1108 isl_int_init(tmp);
1109 for (i = 0; i < mat->n_row; ++i) {
1110 isl_int_mul(tmp, m1, mat->row[i][src1]);
1111 isl_int_addmul(tmp, m2, mat->row[i][src2]);
1112 isl_int_set(mat->row[i][dst], tmp);
1114 isl_int_clear(tmp);
1117 __isl_give isl_mat *isl_mat_right_inverse(__isl_take isl_mat *mat)
1119 struct isl_mat *inv;
1120 int row;
1121 isl_int a, b;
1123 mat = isl_mat_cow(mat);
1124 if (!mat)
1125 return NULL;
1127 inv = isl_mat_identity(mat->ctx, mat->n_col);
1128 inv = isl_mat_cow(inv);
1129 if (!inv)
1130 goto error;
1132 isl_int_init(a);
1133 isl_int_init(b);
1134 for (row = 0; row < mat->n_row; ++row) {
1135 int pivot, first, i, off;
1136 pivot = isl_seq_abs_min_non_zero(mat->row[row]+row, mat->n_col-row);
1137 if (pivot < 0) {
1138 isl_int_clear(a);
1139 isl_int_clear(b);
1140 isl_assert(mat->ctx, pivot >= 0, goto error);
1142 pivot += row;
1143 if (pivot != row)
1144 exchange(mat, &inv, NULL, row, pivot, row);
1145 if (isl_int_is_neg(mat->row[row][row]))
1146 oppose(mat, &inv, NULL, row, row);
1147 first = row+1;
1148 while ((off = isl_seq_first_non_zero(mat->row[row]+first,
1149 mat->n_col-first)) != -1) {
1150 first += off;
1151 isl_int_fdiv_q(a, mat->row[row][first],
1152 mat->row[row][row]);
1153 subtract(mat, &inv, NULL, row, row, first, a);
1154 if (!isl_int_is_zero(mat->row[row][first]))
1155 exchange(mat, &inv, NULL, row, row, first);
1156 else
1157 ++first;
1159 for (i = 0; i < row; ++i) {
1160 if (isl_int_is_zero(mat->row[row][i]))
1161 continue;
1162 isl_int_gcd(a, mat->row[row][row], mat->row[row][i]);
1163 isl_int_divexact(b, mat->row[row][i], a);
1164 isl_int_divexact(a, mat->row[row][row], a);
1165 isl_int_neg(a, a);
1166 isl_mat_col_combine(mat, i, a, i, b, row);
1167 isl_mat_col_combine(inv, i, a, i, b, row);
1170 isl_int_clear(b);
1172 isl_int_set(a, mat->row[0][0]);
1173 for (row = 1; row < mat->n_row; ++row)
1174 isl_int_lcm(a, a, mat->row[row][row]);
1175 if (isl_int_is_zero(a)){
1176 isl_int_clear(a);
1177 goto error;
1179 for (row = 0; row < mat->n_row; ++row) {
1180 isl_int_divexact(mat->row[row][row], a, mat->row[row][row]);
1181 if (isl_int_is_one(mat->row[row][row]))
1182 continue;
1183 isl_mat_col_scale(inv, row, mat->row[row][row]);
1185 isl_int_clear(a);
1187 isl_mat_free(mat);
1189 return inv;
1190 error:
1191 isl_mat_free(mat);
1192 isl_mat_free(inv);
1193 return NULL;
1196 __isl_give isl_mat *isl_mat_transpose(__isl_take isl_mat *mat)
1198 struct isl_mat *transpose = NULL;
1199 int i, j;
1201 if (!mat)
1202 return NULL;
1204 if (mat->n_col == mat->n_row) {
1205 mat = isl_mat_cow(mat);
1206 if (!mat)
1207 return NULL;
1208 for (i = 0; i < mat->n_row; ++i)
1209 for (j = i + 1; j < mat->n_col; ++j)
1210 isl_int_swap(mat->row[i][j], mat->row[j][i]);
1211 return mat;
1213 transpose = isl_mat_alloc(mat->ctx, mat->n_col, mat->n_row);
1214 if (!transpose)
1215 goto error;
1216 for (i = 0; i < mat->n_row; ++i)
1217 for (j = 0; j < mat->n_col; ++j)
1218 isl_int_set(transpose->row[j][i], mat->row[i][j]);
1219 isl_mat_free(mat);
1220 return transpose;
1221 error:
1222 isl_mat_free(mat);
1223 return NULL;
1226 __isl_give isl_mat *isl_mat_swap_cols(__isl_take isl_mat *mat,
1227 unsigned i, unsigned j)
1229 int r;
1231 mat = isl_mat_cow(mat);
1232 if (check_col_range(mat, i, 1) < 0 ||
1233 check_col_range(mat, j, 1) < 0)
1234 return isl_mat_free(mat);
1236 for (r = 0; r < mat->n_row; ++r)
1237 isl_int_swap(mat->row[r][i], mat->row[r][j]);
1238 return mat;
1241 __isl_give isl_mat *isl_mat_swap_rows(__isl_take isl_mat *mat,
1242 unsigned i, unsigned j)
1244 isl_int *t;
1246 if (!mat)
1247 return NULL;
1248 mat = isl_mat_cow(mat);
1249 if (check_row_range(mat, i, 1) < 0 ||
1250 check_row_range(mat, j, 1) < 0)
1251 return isl_mat_free(mat);
1253 t = mat->row[i];
1254 mat->row[i] = mat->row[j];
1255 mat->row[j] = t;
1256 return mat;
1259 /* Calculate the product of two matrices.
1261 * This function is optimized for operand matrices that contain many zeros and
1262 * skips multiplications where we know one of the operands is zero.
1264 __isl_give isl_mat *isl_mat_product(__isl_take isl_mat *left,
1265 __isl_take isl_mat *right)
1267 int i, j, k;
1268 struct isl_mat *prod;
1270 if (!left || !right)
1271 goto error;
1272 isl_assert(left->ctx, left->n_col == right->n_row, goto error);
1273 prod = isl_mat_alloc(left->ctx, left->n_row, right->n_col);
1274 if (!prod)
1275 goto error;
1276 if (left->n_col == 0) {
1277 for (i = 0; i < prod->n_row; ++i)
1278 isl_seq_clr(prod->row[i], prod->n_col);
1279 isl_mat_free(left);
1280 isl_mat_free(right);
1281 return prod;
1283 for (i = 0; i < prod->n_row; ++i) {
1284 for (j = 0; j < prod->n_col; ++j)
1285 isl_int_mul(prod->row[i][j],
1286 left->row[i][0], right->row[0][j]);
1287 for (k = 1; k < left->n_col; ++k) {
1288 if (isl_int_is_zero(left->row[i][k]))
1289 continue;
1290 for (j = 0; j < prod->n_col; ++j)
1291 isl_int_addmul(prod->row[i][j],
1292 left->row[i][k], right->row[k][j]);
1295 isl_mat_free(left);
1296 isl_mat_free(right);
1297 return prod;
1298 error:
1299 isl_mat_free(left);
1300 isl_mat_free(right);
1301 return NULL;
1304 /* Replace the variables x in the rows q by x' given by x = M x',
1305 * with M the matrix mat.
1307 * If the number of new variables is greater than the original
1308 * number of variables, then the rows q have already been
1309 * preextended. If the new number is smaller, then the coefficients
1310 * of the divs, which are not changed, need to be shifted down.
1311 * The row q may be the equalities, the inequalities or the
1312 * div expressions. In the latter case, has_div is true and
1313 * we need to take into account the extra denominator column.
1315 static int preimage(struct isl_ctx *ctx, isl_int **q, unsigned n,
1316 unsigned n_div, int has_div, struct isl_mat *mat)
1318 int i;
1319 struct isl_mat *t;
1320 int e;
1322 if (mat->n_col >= mat->n_row)
1323 e = 0;
1324 else
1325 e = mat->n_row - mat->n_col;
1326 if (has_div)
1327 for (i = 0; i < n; ++i)
1328 isl_int_mul(q[i][0], q[i][0], mat->row[0][0]);
1329 t = isl_mat_sub_alloc6(mat->ctx, q, 0, n, has_div, mat->n_row);
1330 t = isl_mat_product(t, mat);
1331 if (!t)
1332 return -1;
1333 for (i = 0; i < n; ++i) {
1334 isl_seq_swp_or_cpy(q[i] + has_div, t->row[i], t->n_col);
1335 isl_seq_cpy(q[i] + has_div + t->n_col,
1336 q[i] + has_div + t->n_col + e, n_div);
1337 isl_seq_clr(q[i] + has_div + t->n_col + n_div, e);
1339 isl_mat_free(t);
1340 return 0;
1343 /* Replace the variables x in bset by x' given by x = M x', with
1344 * M the matrix mat.
1346 * If there are fewer variables x' then there are x, then we perform
1347 * the transformation in place, which means that, in principle,
1348 * this frees up some extra variables as the number
1349 * of columns remains constant, but we would have to extend
1350 * the div array too as the number of rows in this array is assumed
1351 * to be equal to extra.
1353 __isl_give isl_basic_set *isl_basic_set_preimage(
1354 __isl_take isl_basic_set *bset, __isl_take isl_mat *mat)
1356 struct isl_ctx *ctx;
1358 if (!bset || !mat)
1359 goto error;
1361 ctx = bset->ctx;
1362 bset = isl_basic_set_cow(bset);
1363 if (!bset)
1364 goto error;
1366 isl_assert(ctx, bset->dim->nparam == 0, goto error);
1367 isl_assert(ctx, 1+bset->dim->n_out == mat->n_row, goto error);
1368 isl_assert(ctx, mat->n_col > 0, goto error);
1370 if (mat->n_col > mat->n_row) {
1371 bset = isl_basic_set_add_dims(bset, isl_dim_set,
1372 mat->n_col - mat->n_row);
1373 if (!bset)
1374 goto error;
1375 } else if (mat->n_col < mat->n_row) {
1376 bset->dim = isl_space_cow(bset->dim);
1377 if (!bset->dim)
1378 goto error;
1379 bset->dim->n_out -= mat->n_row - mat->n_col;
1382 if (preimage(ctx, bset->eq, bset->n_eq, bset->n_div, 0,
1383 isl_mat_copy(mat)) < 0)
1384 goto error;
1386 if (preimage(ctx, bset->ineq, bset->n_ineq, bset->n_div, 0,
1387 isl_mat_copy(mat)) < 0)
1388 goto error;
1390 if (preimage(ctx, bset->div, bset->n_div, bset->n_div, 1, mat) < 0)
1391 goto error2;
1393 ISL_F_CLR(bset, ISL_BASIC_SET_NO_IMPLICIT);
1394 ISL_F_CLR(bset, ISL_BASIC_SET_NO_REDUNDANT);
1395 ISL_F_CLR(bset, ISL_BASIC_SET_SORTED);
1396 ISL_F_CLR(bset, ISL_BASIC_SET_NORMALIZED_DIVS);
1397 ISL_F_CLR(bset, ISL_BASIC_SET_ALL_EQUALITIES);
1399 bset = isl_basic_set_simplify(bset);
1400 bset = isl_basic_set_finalize(bset);
1402 return bset;
1403 error:
1404 isl_mat_free(mat);
1405 error2:
1406 isl_basic_set_free(bset);
1407 return NULL;
1410 __isl_give isl_set *isl_set_preimage(
1411 __isl_take isl_set *set, __isl_take isl_mat *mat)
1413 int i;
1415 set = isl_set_cow(set);
1416 if (!set)
1417 goto error;
1419 for (i = 0; i < set->n; ++i) {
1420 set->p[i] = isl_basic_set_preimage(set->p[i],
1421 isl_mat_copy(mat));
1422 if (!set->p[i])
1423 goto error;
1425 if (mat->n_col != mat->n_row) {
1426 set->dim = isl_space_cow(set->dim);
1427 if (!set->dim)
1428 goto error;
1429 set->dim->n_out += mat->n_col;
1430 set->dim->n_out -= mat->n_row;
1432 isl_mat_free(mat);
1433 ISL_F_CLR(set, ISL_SET_NORMALIZED);
1434 return set;
1435 error:
1436 isl_set_free(set);
1437 isl_mat_free(mat);
1438 return NULL;
1441 /* Replace the variables x starting at "first_col" in the rows "rows"
1442 * of some coefficient matrix by x' with x = M x' with M the matrix mat.
1443 * That is, replace the corresponding coefficients c by c M.
1445 isl_stat isl_mat_sub_transform(isl_int **row, unsigned n_row,
1446 unsigned first_col, __isl_take isl_mat *mat)
1448 int i;
1449 isl_ctx *ctx;
1450 isl_mat *t;
1452 if (!mat)
1453 return isl_stat_error;
1454 ctx = isl_mat_get_ctx(mat);
1455 t = isl_mat_sub_alloc6(ctx, row, 0, n_row, first_col, mat->n_row);
1456 t = isl_mat_product(t, mat);
1457 if (!t)
1458 return isl_stat_error;
1459 for (i = 0; i < n_row; ++i)
1460 isl_seq_swp_or_cpy(row[i] + first_col, t->row[i], t->n_col);
1461 isl_mat_free(t);
1462 return isl_stat_ok;
1465 void isl_mat_print_internal(__isl_keep isl_mat *mat, FILE *out, int indent)
1467 int i, j;
1469 if (!mat) {
1470 fprintf(out, "%*snull mat\n", indent, "");
1471 return;
1474 if (mat->n_row == 0)
1475 fprintf(out, "%*s[]\n", indent, "");
1477 for (i = 0; i < mat->n_row; ++i) {
1478 if (!i)
1479 fprintf(out, "%*s[[", indent, "");
1480 else
1481 fprintf(out, "%*s[", indent+1, "");
1482 for (j = 0; j < mat->n_col; ++j) {
1483 if (j)
1484 fprintf(out, ",");
1485 isl_int_print(out, mat->row[i][j], 0);
1487 if (i == mat->n_row-1)
1488 fprintf(out, "]]\n");
1489 else
1490 fprintf(out, "]\n");
1494 void isl_mat_dump(__isl_keep isl_mat *mat)
1496 isl_mat_print_internal(mat, stderr, 0);
1499 __isl_give isl_mat *isl_mat_drop_cols(__isl_take isl_mat *mat,
1500 unsigned col, unsigned n)
1502 int r;
1504 if (n == 0)
1505 return mat;
1507 mat = isl_mat_cow(mat);
1508 if (check_col_range(mat, col, n) < 0)
1509 return isl_mat_free(mat);
1511 if (col != mat->n_col-n) {
1512 for (r = 0; r < mat->n_row; ++r)
1513 isl_seq_cpy(mat->row[r]+col, mat->row[r]+col+n,
1514 mat->n_col - col - n);
1516 mat->n_col -= n;
1517 return mat;
1520 __isl_give isl_mat *isl_mat_drop_rows(__isl_take isl_mat *mat,
1521 unsigned row, unsigned n)
1523 int r;
1525 mat = isl_mat_cow(mat);
1526 if (check_row_range(mat, row, n) < 0)
1527 return isl_mat_free(mat);
1529 for (r = row; r+n < mat->n_row; ++r)
1530 mat->row[r] = mat->row[r+n];
1532 mat->n_row -= n;
1533 return mat;
1536 __isl_give isl_mat *isl_mat_insert_cols(__isl_take isl_mat *mat,
1537 unsigned col, unsigned n)
1539 isl_mat *ext;
1541 if (check_col_range(mat, col, 0) < 0)
1542 return isl_mat_free(mat);
1543 if (n == 0)
1544 return mat;
1546 ext = isl_mat_alloc(mat->ctx, mat->n_row, mat->n_col + n);
1547 if (!ext)
1548 goto error;
1550 isl_mat_sub_copy(mat->ctx, ext->row, mat->row, mat->n_row, 0, 0, col);
1551 isl_mat_sub_copy(mat->ctx, ext->row, mat->row, mat->n_row,
1552 col + n, col, mat->n_col - col);
1554 isl_mat_free(mat);
1555 return ext;
1556 error:
1557 isl_mat_free(mat);
1558 return NULL;
1561 __isl_give isl_mat *isl_mat_insert_zero_cols(__isl_take isl_mat *mat,
1562 unsigned first, unsigned n)
1564 int i;
1566 if (!mat)
1567 return NULL;
1568 mat = isl_mat_insert_cols(mat, first, n);
1569 if (!mat)
1570 return NULL;
1572 for (i = 0; i < mat->n_row; ++i)
1573 isl_seq_clr(mat->row[i] + first, n);
1575 return mat;
1578 __isl_give isl_mat *isl_mat_add_zero_cols(__isl_take isl_mat *mat, unsigned n)
1580 if (!mat)
1581 return NULL;
1583 return isl_mat_insert_zero_cols(mat, mat->n_col, n);
1586 __isl_give isl_mat *isl_mat_insert_rows(__isl_take isl_mat *mat,
1587 unsigned row, unsigned n)
1589 isl_mat *ext;
1591 if (check_row_range(mat, row, 0) < 0)
1592 return isl_mat_free(mat);
1593 if (n == 0)
1594 return mat;
1596 ext = isl_mat_alloc(mat->ctx, mat->n_row + n, mat->n_col);
1597 if (!ext)
1598 goto error;
1600 isl_mat_sub_copy(mat->ctx, ext->row, mat->row, row, 0, 0, mat->n_col);
1601 isl_mat_sub_copy(mat->ctx, ext->row + row + n, mat->row + row,
1602 mat->n_row - row, 0, 0, mat->n_col);
1604 isl_mat_free(mat);
1605 return ext;
1606 error:
1607 isl_mat_free(mat);
1608 return NULL;
1611 __isl_give isl_mat *isl_mat_add_rows(__isl_take isl_mat *mat, unsigned n)
1613 if (!mat)
1614 return NULL;
1616 return isl_mat_insert_rows(mat, mat->n_row, n);
1619 __isl_give isl_mat *isl_mat_insert_zero_rows(__isl_take isl_mat *mat,
1620 unsigned row, unsigned n)
1622 int i;
1624 mat = isl_mat_insert_rows(mat, row, n);
1625 if (!mat)
1626 return NULL;
1628 for (i = 0; i < n; ++i)
1629 isl_seq_clr(mat->row[row + i], mat->n_col);
1631 return mat;
1634 __isl_give isl_mat *isl_mat_add_zero_rows(__isl_take isl_mat *mat, unsigned n)
1636 if (!mat)
1637 return NULL;
1639 return isl_mat_insert_zero_rows(mat, mat->n_row, n);
1642 void isl_mat_col_submul(struct isl_mat *mat,
1643 int dst_col, isl_int f, int src_col)
1645 int i;
1647 for (i = 0; i < mat->n_row; ++i)
1648 isl_int_submul(mat->row[i][dst_col], f, mat->row[i][src_col]);
1651 void isl_mat_col_add(__isl_keep isl_mat *mat, int dst_col, int src_col)
1653 int i;
1655 if (!mat)
1656 return;
1658 for (i = 0; i < mat->n_row; ++i)
1659 isl_int_add(mat->row[i][dst_col],
1660 mat->row[i][dst_col], mat->row[i][src_col]);
1663 void isl_mat_col_mul(struct isl_mat *mat, int dst_col, isl_int f, int src_col)
1665 int i;
1667 for (i = 0; i < mat->n_row; ++i)
1668 isl_int_mul(mat->row[i][dst_col], f, mat->row[i][src_col]);
1671 /* Add "f" times column "src_col" to column "dst_col" of "mat" and
1672 * return the result.
1674 __isl_give isl_mat *isl_mat_col_addmul(__isl_take isl_mat *mat, int dst_col,
1675 isl_int f, int src_col)
1677 int i;
1679 if (check_col(mat, dst_col) < 0 || check_col(mat, src_col) < 0)
1680 return isl_mat_free(mat);
1682 for (i = 0; i < mat->n_row; ++i) {
1683 if (isl_int_is_zero(mat->row[i][src_col]))
1684 continue;
1685 mat = isl_mat_cow(mat);
1686 if (!mat)
1687 return NULL;
1688 isl_int_addmul(mat->row[i][dst_col], f, mat->row[i][src_col]);
1691 return mat;
1694 /* Negate column "col" of "mat" and return the result.
1696 __isl_give isl_mat *isl_mat_col_neg(__isl_take isl_mat *mat, int col)
1698 int i;
1700 if (check_col(mat, col) < 0)
1701 return isl_mat_free(mat);
1703 for (i = 0; i < mat->n_row; ++i) {
1704 if (isl_int_is_zero(mat->row[i][col]))
1705 continue;
1706 mat = isl_mat_cow(mat);
1707 if (!mat)
1708 return NULL;
1709 isl_int_neg(mat->row[i][col], mat->row[i][col]);
1712 return mat;
1715 /* Negate row "row" of "mat" and return the result.
1717 __isl_give isl_mat *isl_mat_row_neg(__isl_take isl_mat *mat, int row)
1719 if (check_row(mat, row) < 0)
1720 return isl_mat_free(mat);
1721 if (isl_seq_first_non_zero(mat->row[row], mat->n_col) == -1)
1722 return mat;
1723 mat = isl_mat_cow(mat);
1724 if (!mat)
1725 return NULL;
1726 isl_seq_neg(mat->row[row], mat->row[row], mat->n_col);
1727 return mat;
1730 __isl_give isl_mat *isl_mat_unimodular_complete(__isl_take isl_mat *M, int row)
1732 int r;
1733 struct isl_mat *H = NULL, *Q = NULL;
1735 if (!M)
1736 return NULL;
1738 isl_assert(M->ctx, M->n_row == M->n_col, goto error);
1739 M->n_row = row;
1740 H = isl_mat_left_hermite(isl_mat_copy(M), 0, NULL, &Q);
1741 M->n_row = M->n_col;
1742 if (!H)
1743 goto error;
1744 for (r = 0; r < row; ++r)
1745 isl_assert(M->ctx, isl_int_is_one(H->row[r][r]), goto error);
1746 for (r = row; r < M->n_row; ++r)
1747 isl_seq_cpy(M->row[r], Q->row[r], M->n_col);
1748 isl_mat_free(H);
1749 isl_mat_free(Q);
1750 return M;
1751 error:
1752 isl_mat_free(H);
1753 isl_mat_free(Q);
1754 isl_mat_free(M);
1755 return NULL;
1758 __isl_give isl_mat *isl_mat_concat(__isl_take isl_mat *top,
1759 __isl_take isl_mat *bot)
1761 struct isl_mat *mat;
1763 if (!top || !bot)
1764 goto error;
1766 isl_assert(top->ctx, top->n_col == bot->n_col, goto error);
1767 if (top->n_row == 0) {
1768 isl_mat_free(top);
1769 return bot;
1771 if (bot->n_row == 0) {
1772 isl_mat_free(bot);
1773 return top;
1776 mat = isl_mat_alloc(top->ctx, top->n_row + bot->n_row, top->n_col);
1777 if (!mat)
1778 goto error;
1779 isl_mat_sub_copy(mat->ctx, mat->row, top->row, top->n_row,
1780 0, 0, mat->n_col);
1781 isl_mat_sub_copy(mat->ctx, mat->row + top->n_row, bot->row, bot->n_row,
1782 0, 0, mat->n_col);
1783 isl_mat_free(top);
1784 isl_mat_free(bot);
1785 return mat;
1786 error:
1787 isl_mat_free(top);
1788 isl_mat_free(bot);
1789 return NULL;
1792 isl_bool isl_mat_is_equal(__isl_keep isl_mat *mat1, __isl_keep isl_mat *mat2)
1794 int i;
1796 if (!mat1 || !mat2)
1797 return isl_bool_error;
1799 if (mat1->n_row != mat2->n_row)
1800 return isl_bool_false;
1802 if (mat1->n_col != mat2->n_col)
1803 return isl_bool_false;
1805 for (i = 0; i < mat1->n_row; ++i)
1806 if (!isl_seq_eq(mat1->row[i], mat2->row[i], mat1->n_col))
1807 return isl_bool_false;
1809 return isl_bool_true;
1812 __isl_give isl_mat *isl_mat_from_row_vec(__isl_take isl_vec *vec)
1814 struct isl_mat *mat;
1816 if (!vec)
1817 return NULL;
1818 mat = isl_mat_alloc(vec->ctx, 1, vec->size);
1819 if (!mat)
1820 goto error;
1822 isl_seq_cpy(mat->row[0], vec->el, vec->size);
1824 isl_vec_free(vec);
1825 return mat;
1826 error:
1827 isl_vec_free(vec);
1828 return NULL;
1831 /* Return a copy of row "row" of "mat" as an isl_vec.
1833 __isl_give isl_vec *isl_mat_get_row(__isl_keep isl_mat *mat, unsigned row)
1835 isl_vec *v;
1837 if (!mat)
1838 return NULL;
1839 if (row >= mat->n_row)
1840 isl_die(mat->ctx, isl_error_invalid, "row out of range",
1841 return NULL);
1843 v = isl_vec_alloc(isl_mat_get_ctx(mat), mat->n_col);
1844 if (!v)
1845 return NULL;
1846 isl_seq_cpy(v->el, mat->row[row], mat->n_col);
1848 return v;
1851 __isl_give isl_mat *isl_mat_vec_concat(__isl_take isl_mat *top,
1852 __isl_take isl_vec *bot)
1854 return isl_mat_concat(top, isl_mat_from_row_vec(bot));
1857 __isl_give isl_mat *isl_mat_move_cols(__isl_take isl_mat *mat,
1858 unsigned dst_col, unsigned src_col, unsigned n)
1860 isl_mat *res;
1862 if (!mat)
1863 return NULL;
1864 if (n == 0 || dst_col == src_col)
1865 return mat;
1867 res = isl_mat_alloc(mat->ctx, mat->n_row, mat->n_col);
1868 if (!res)
1869 goto error;
1871 if (dst_col < src_col) {
1872 isl_mat_sub_copy(res->ctx, res->row, mat->row, mat->n_row,
1873 0, 0, dst_col);
1874 isl_mat_sub_copy(res->ctx, res->row, mat->row, mat->n_row,
1875 dst_col, src_col, n);
1876 isl_mat_sub_copy(res->ctx, res->row, mat->row, mat->n_row,
1877 dst_col + n, dst_col, src_col - dst_col);
1878 isl_mat_sub_copy(res->ctx, res->row, mat->row, mat->n_row,
1879 src_col + n, src_col + n,
1880 res->n_col - src_col - n);
1881 } else {
1882 isl_mat_sub_copy(res->ctx, res->row, mat->row, mat->n_row,
1883 0, 0, src_col);
1884 isl_mat_sub_copy(res->ctx, res->row, mat->row, mat->n_row,
1885 src_col, src_col + n, dst_col - src_col);
1886 isl_mat_sub_copy(res->ctx, res->row, mat->row, mat->n_row,
1887 dst_col, src_col, n);
1888 isl_mat_sub_copy(res->ctx, res->row, mat->row, mat->n_row,
1889 dst_col + n, dst_col + n,
1890 res->n_col - dst_col - n);
1892 isl_mat_free(mat);
1894 return res;
1895 error:
1896 isl_mat_free(mat);
1897 return NULL;
1900 /* Return the gcd of the elements in row "row" of "mat" in *gcd.
1901 * Return isl_stat_ok on success and isl_stat_error on failure.
1903 isl_stat isl_mat_row_gcd(__isl_keep isl_mat *mat, int row, isl_int *gcd)
1905 if (check_row(mat, row) < 0)
1906 return isl_stat_error;
1908 isl_seq_gcd(mat->row[row], mat->n_col, gcd);
1910 return isl_stat_ok;
1913 void isl_mat_gcd(__isl_keep isl_mat *mat, isl_int *gcd)
1915 int i;
1916 isl_int g;
1918 isl_int_set_si(*gcd, 0);
1919 if (!mat)
1920 return;
1922 isl_int_init(g);
1923 for (i = 0; i < mat->n_row; ++i) {
1924 isl_seq_gcd(mat->row[i], mat->n_col, &g);
1925 isl_int_gcd(*gcd, *gcd, g);
1927 isl_int_clear(g);
1930 /* Return the result of scaling "mat" by a factor of "m".
1932 __isl_give isl_mat *isl_mat_scale(__isl_take isl_mat *mat, isl_int m)
1934 int i;
1936 if (isl_int_is_one(m))
1937 return mat;
1939 mat = isl_mat_cow(mat);
1940 if (!mat)
1941 return NULL;
1943 for (i = 0; i < mat->n_row; ++i)
1944 isl_seq_scale(mat->row[i], mat->row[i], m, mat->n_col);
1946 return mat;
1949 __isl_give isl_mat *isl_mat_scale_down(__isl_take isl_mat *mat, isl_int m)
1951 int i;
1953 if (isl_int_is_one(m))
1954 return mat;
1956 mat = isl_mat_cow(mat);
1957 if (!mat)
1958 return NULL;
1960 for (i = 0; i < mat->n_row; ++i)
1961 isl_seq_scale_down(mat->row[i], mat->row[i], m, mat->n_col);
1963 return mat;
1966 __isl_give isl_mat *isl_mat_scale_down_row(__isl_take isl_mat *mat, int row,
1967 isl_int m)
1969 if (isl_int_is_one(m))
1970 return mat;
1972 mat = isl_mat_cow(mat);
1973 if (!mat)
1974 return NULL;
1976 isl_seq_scale_down(mat->row[row], mat->row[row], m, mat->n_col);
1978 return mat;
1981 __isl_give isl_mat *isl_mat_normalize(__isl_take isl_mat *mat)
1983 isl_int gcd;
1985 if (!mat)
1986 return NULL;
1988 isl_int_init(gcd);
1989 isl_mat_gcd(mat, &gcd);
1990 mat = isl_mat_scale_down(mat, gcd);
1991 isl_int_clear(gcd);
1993 return mat;
1996 __isl_give isl_mat *isl_mat_normalize_row(__isl_take isl_mat *mat, int row)
1998 mat = isl_mat_cow(mat);
1999 if (!mat)
2000 return NULL;
2002 isl_seq_normalize(mat->ctx, mat->row[row], mat->n_col);
2004 return mat;
2007 /* Number of initial non-zero columns.
2009 int isl_mat_initial_non_zero_cols(__isl_keep isl_mat *mat)
2011 int i;
2013 if (!mat)
2014 return -1;
2016 for (i = 0; i < mat->n_col; ++i)
2017 if (row_first_non_zero(mat->row, mat->n_row, i) < 0)
2018 break;
2020 return i;
2023 /* Return a basis for the space spanned by the rows of "mat".
2024 * Any basis will do, so simply perform Gaussian elimination and
2025 * remove the empty rows.
2027 __isl_give isl_mat *isl_mat_row_basis(__isl_take isl_mat *mat)
2029 return isl_mat_reverse_gauss(mat);
2032 /* Return rows that extend a basis of "mat1" to one
2033 * that covers both "mat1" and "mat2".
2034 * The Hermite normal form of the concatenation of the two matrices is
2036 * [ Q1 ]
2037 * [ M1 ] = [ H1 0 0 ] [ Q2 ]
2038 * [ M2 ] = [ H2 H3 0 ] [ Q3 ]
2040 * The number of columns in H1 and H3 determine the number of rows
2041 * in Q1 and Q2. Q1 is a basis for M1, while Q2 extends this basis
2042 * to also cover M2.
2044 __isl_give isl_mat *isl_mat_row_basis_extension(
2045 __isl_take isl_mat *mat1, __isl_take isl_mat *mat2)
2047 int n_row;
2048 int r1, r, n1;
2049 isl_mat *H, *Q;
2051 n1 = isl_mat_rows(mat1);
2052 H = isl_mat_concat(mat1, mat2);
2053 H = isl_mat_left_hermite(H, 0, NULL, &Q);
2054 if (!H || !Q)
2055 goto error;
2057 r1 = hermite_first_zero_col(H, 0, n1);
2058 r = hermite_first_zero_col(H, r1, H->n_row);
2059 n_row = isl_mat_rows(Q);
2060 Q = isl_mat_drop_rows(Q, r, n_row - r);
2061 Q = isl_mat_drop_rows(Q, 0, r1);
2063 isl_mat_free(H);
2064 return Q;
2065 error:
2066 isl_mat_free(H);
2067 isl_mat_free(Q);
2068 return NULL;
2071 /* Are the rows of "mat1" linearly independent of those of "mat2"?
2072 * That is, is there no linear dependence among the combined rows
2073 * that is not already present in either "mat1" or "mat2"?
2074 * In other words, is the rank of "mat1" and "mat2" combined equal
2075 * to the sum of the ranks of "mat1" and "mat2"?
2077 isl_bool isl_mat_has_linearly_independent_rows(__isl_keep isl_mat *mat1,
2078 __isl_keep isl_mat *mat2)
2080 int r1, r2, r;
2081 isl_mat *mat;
2083 r1 = isl_mat_rank(mat1);
2084 if (r1 < 0)
2085 return isl_bool_error;
2086 if (r1 == 0)
2087 return isl_bool_true;
2088 r2 = isl_mat_rank(mat2);
2089 if (r2 < 0)
2090 return isl_bool_error;
2091 if (r2 == 0)
2092 return isl_bool_true;
2094 mat = isl_mat_concat(isl_mat_copy(mat1), isl_mat_copy(mat2));
2095 r = isl_mat_rank(mat);
2096 isl_mat_free(mat);
2097 if (r < 0)
2098 return isl_bool_error;
2099 return r == r1 + r2;