print.c

   1 /*
   2  * Copyright 2011 Leiden University. All rights reserved.
   3  * Copyright 2012-2013 Ecole Normale Superieure. All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  *
   9  *    1. Redistributions of source code must retain the above copyright
  10  *       notice, this list of conditions and the following disclaimer.
  11  *
  12  *    2. Redistributions in binary form must reproduce the above
  13  *       copyright notice, this list of conditions and the following
  14  *       disclaimer in the documentation and/or other materials provided
  15  *       with the distribution.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY LEIDEN UNIVERSITY ''AS IS'' AND ANY
  18  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  20  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL LEIDEN UNIVERSITY OR
  21  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  22  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  23  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
  24  * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  25  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  26  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  27  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  *
  29  * The views and conclusions contained in the software and documentation
  30  * are those of the authors and should not be interpreted as
  31  * representing official policies, either expressed or implied, of
  32  * Leiden University.
  33  */
  34
  35 #include <isl/aff.h>
  36 #include <isl/ast.h>
  37 #include <isl/ast_build.h>
  38 #include <pet.h>
  39 #include "scop.h"
  40
  41 /* Internal data structure for pet_stmt_build_ast_exprs.
  42  *
  43  * "build" is used to construct an AST expression from an index expression.
  44  * "fn_index" is used to transform the index expression prior to
  45  *      the construction of the AST expression.
  46  * "fn_expr" is used to transform the constructed AST expression.
  47  * "ref2expr" collects the results.
  48  */
  49 struct pet_build_ast_expr_data {
  50         isl_ast_build *build;
  51         __isl_give isl_multi_pw_aff *(*fn_index)(
  52                 __isl_take isl_multi_pw_aff *mpa, __isl_keep isl_id *id,
  53                 void *user);
  54         void *user_index;
  55         __isl_give isl_ast_expr *(*fn_expr)(__isl_take isl_ast_expr *expr,
  56                 __isl_keep isl_id *id, void *user);
  57         void *user_expr;
  58         isl_id_to_ast_expr *ref2expr;
  59 };
  60
  61 /* Given an index expression "index" with nested expressions, replace
  62  * those nested expressions by parameters.  The identifiers
  63  * of those parameters reference the corresponding arguments
  64  * of "expr".  The same identifiers are used in
  65  * pet_expr_build_nested_ast_exprs.
  66  *
  67  * In particular, if "index" is of the form
  68  *
  69  *      { [domain -> [e_1, ..., e_n]] -> array[f(e_1, ..., e_n)] }
  70  *
  71  * then we construct the expression
  72  *
  73  *      [p_1, ..., p_n] -> { domain -> array[f(p_1, ..., p_n)] }
  74  *
  75  */
  76 static __isl_give isl_multi_pw_aff *parametrize_nested_exprs(
  77         __isl_take isl_multi_pw_aff *index, struct pet_expr *expr)
  78 {
  79         int i;
  80         isl_ctx *ctx;
  81         isl_space *space, *space2;
  82         isl_local_space *ls;
  83         isl_multi_aff *ma, *ma2;
  84
  85         ctx = isl_multi_pw_aff_get_ctx(index);
  86         space = isl_multi_pw_aff_get_domain_space(index);
  87         space = isl_space_unwrap(space);
  88
  89         space2 = isl_space_domain(isl_space_copy(space));
  90         ma = isl_multi_aff_identity(isl_space_map_from_set(space2));
  91
  92         space = isl_space_insert_dims(space, isl_dim_param, 0,
  93                                         expr->n_arg);
  94         for (i = 0; i < expr->n_arg; ++i) {
  95                 isl_id *id = isl_id_alloc(ctx, NULL, expr->args[i]);
  96
  97                 space = isl_space_set_dim_id(space, isl_dim_param, i, id);
  98         }
  99         space2 = isl_space_domain(isl_space_copy(space));
 100         ls = isl_local_space_from_space(space2);
 101         ma2 = isl_multi_aff_zero(space);
 102         for (i = 0; i < expr->n_arg; ++i) {
 103                 isl_aff *aff;
 104                 aff = isl_aff_var_on_domain(isl_local_space_copy(ls),
 105                                                 isl_dim_param, i);
 106                 ma2 = isl_multi_aff_set_aff(ma2, i, aff);
 107         }
 108         isl_local_space_free(ls);
 109
 110         ma = isl_multi_aff_range_product(ma, ma2);
 111
 112         return isl_multi_pw_aff_pullback_multi_aff(index, ma);
 113 }
 114
 115 static __isl_give isl_ast_expr *pet_expr_build_ast_expr(struct pet_expr *expr,
 116         struct pet_build_ast_expr_data *data);
 117
 118 /* Construct an associative array from identifiers for the nested
 119  * expressions of "expr" to the corresponding isl_ast_expr.
 120  * The identifiers reference the corresponding arguments of "expr".
 121  * The same identifiers are used in parametrize_nested_exprs.
 122  */
 123 static __isl_give isl_id_to_ast_expr *pet_expr_build_nested_ast_exprs(
 124         struct pet_expr *expr, struct pet_build_ast_expr_data *data)
 125 {
 126         int i;
 127         isl_ctx *ctx = isl_ast_build_get_ctx(data->build);
 128         isl_id_to_ast_expr *id2expr;
 129
 130         id2expr = isl_id_to_ast_expr_alloc(ctx, expr->n_arg);
 131
 132         for (i = 0; i < expr->n_arg; ++i) {
 133                 isl_id *id = isl_id_alloc(ctx, NULL, expr->args[i]);
 134                 isl_ast_expr *ast_expr;
 135
 136                 ast_expr = pet_expr_build_ast_expr(expr->args[i], data);
 137                 id2expr = isl_id_to_ast_expr_set(id2expr, id, ast_expr);
 138         }
 139
 140         return id2expr;
 141 }
 142
 143 /* Construct an AST expression from an access expression.
 144  *
 145  * If the expression has any arguments, we first convert those
 146  * to AST expressions and replace the references to those arguments
 147  * in the index expression by parameters.
 148  *
 149  * Then we apply the index transformation if any was provided by the user.
 150  *
 151  * If the "access" is actually an affine expression, we print is as such.
 152  * Otherwise, we print a proper access.
 153  *
 154  * If the original expression had any arguments, then they are plugged in now.
 155  *
 156  * Finally, we apply an AST transformation on the result, if any was provided
 157  * by the user.
 158  */
 159 static __isl_give isl_ast_expr *pet_expr_build_ast_expr(struct pet_expr *expr,
 160         struct pet_build_ast_expr_data *data)
 161 {
 162         isl_pw_aff *pa;
 163         isl_multi_pw_aff *mpa;
 164         isl_ast_expr *ast_expr;
 165         isl_id_to_ast_expr *id2expr;
 166         isl_ast_build *build = data->build;
 167
 168         if (!expr)
 169                 return NULL;
 170         if (expr->type != pet_expr_access)
 171                 isl_die(isl_ast_build_get_ctx(build), isl_error_invalid,
 172                         "not an access expression", return NULL);
 173
 174         mpa = isl_multi_pw_aff_copy(expr->acc.index);
 175
 176         if (expr->n_arg > 0) {
 177                 mpa = parametrize_nested_exprs(mpa, expr);
 178                 id2expr = pet_expr_build_nested_ast_exprs(expr, data);
 179         }
 180
 181         if (data->fn_index)
 182                 mpa = data->fn_index(mpa, expr->acc.ref_id, data->user_index);
 183         mpa = isl_multi_pw_aff_coalesce(mpa);
 184
 185         if (!pet_expr_is_affine(expr)) {
 186                 ast_expr = isl_ast_build_access_from_multi_pw_aff(build, mpa);
 187         } else {
 188                 pa = isl_multi_pw_aff_get_pw_aff(mpa, 0);
 189                 ast_expr = isl_ast_build_expr_from_pw_aff(build, pa);
 190                 isl_multi_pw_aff_free(mpa);
 191         }
 192         if (expr->n_arg > 0)
 193                 ast_expr = isl_ast_expr_substitute_ids(ast_expr, id2expr);
 194         if (data->fn_expr)
 195                 ast_expr = data->fn_expr(ast_expr, expr->acc.ref_id,
 196                                             data->user_index);
 197
 198         return ast_expr;
 199 }
 200
 201 /* Construct an AST expression from the access expression "expr" and
 202  * add the mapping from reference identifier to AST expression to
 203  * data->ref2expr.
 204  */
 205 static int add_access(struct pet_expr *expr, void *user)
 206 {
 207         struct pet_build_ast_expr_data *data = user;
 208         isl_id *id;
 209         isl_ast_expr *ast_expr;
 210
 211         ast_expr = pet_expr_build_ast_expr(expr, data);
 212
 213         id = isl_id_copy(expr->acc.ref_id);
 214         data->ref2expr = isl_id_to_ast_expr_set(data->ref2expr, id, ast_expr);
 215
 216         return 0;
 217 }
 218
 219 /* Construct an associative array from reference identifiers of
 220  * access expressions in "stmt" to the corresponding isl_ast_expr.
 221  * Each index expression is first transformed through "fn_index"
 222  * (if not NULL).  Then an AST expression is generated using "build".
 223  * Finally, the AST expression is transformed using "fn_expr"
 224  * (if not NULL).
 225  */
 226 __isl_give isl_id_to_ast_expr *pet_stmt_build_ast_exprs(struct pet_stmt *stmt,
 227         __isl_keep isl_ast_build *build,
 228         __isl_give isl_multi_pw_aff *(*fn_index)(
 229                 __isl_take isl_multi_pw_aff *mpa, __isl_keep isl_id *id,
 230                 void *user), void *user_index,
 231         __isl_give isl_ast_expr *(*fn_expr)(__isl_take isl_ast_expr *expr,
 232                 __isl_keep isl_id *id, void *user), void *user_expr)
 233 {
 234         struct pet_build_ast_expr_data data =
 235                 { build, fn_index, user_index, fn_expr, user_expr };
 236         isl_ctx *ctx;
 237
 238         if (!stmt || !build)
 239                 return NULL;
 240
 241         ctx = isl_ast_build_get_ctx(build);
 242         data.ref2expr = isl_id_to_ast_expr_alloc(ctx, 0);
 243         if (pet_expr_foreach_access_expr(stmt->body, &add_access, &data) < 0)
 244                 data.ref2expr = isl_id_to_ast_expr_free(data.ref2expr);
 245
 246         return data.ref2expr;
 247 }
 248
 249 /* Print the access expression "expr" to "p".
 250  *
 251  * We look up the corresponding isl_ast_expr in "ref2expr"
 252  * and print that to "p".
 253  */
 254 static __isl_give isl_printer *print_access(__isl_take isl_printer *p,
 255         struct pet_expr *expr, __isl_keep isl_id_to_ast_expr *ref2expr)
 256 {
 257         isl_ast_expr *ast_expr;
 258         int is_access;
 259
 260         if (!isl_id_to_ast_expr_has(ref2expr, expr->acc.ref_id))
 261                 isl_die(isl_printer_get_ctx(p), isl_error_internal,
 262                         "missing expression", return isl_printer_free(p));
 263
 264         ast_expr = isl_id_to_ast_expr_get(ref2expr,
 265                                         isl_id_copy(expr->acc.ref_id));
 266         is_access = isl_ast_expr_get_type(ast_expr) == isl_ast_expr_op &&
 267                 isl_ast_expr_get_op_type(ast_expr) == isl_ast_op_access;
 268         if (!is_access)
 269                 p = isl_printer_print_str(p, "(");
 270         p = isl_printer_print_ast_expr(p, ast_expr);
 271         if (!is_access)
 272                 p = isl_printer_print_str(p, ")");
 273         isl_ast_expr_free(ast_expr);
 274
 275         return p;
 276 }
 277
 278 /* Is "op" a postfix operator?
 279  */
 280 static int is_postfix(enum pet_op_type op)
 281 {
 282         switch (op) {
 283         case pet_op_post_inc:
 284         case pet_op_post_dec:
 285                 return 1;
 286         default:
 287                 return 0;
 288         }
 289 }
 290
 291 /* Print "expr" to "p".
 292  *
 293  * If "outer" is set, then we are printing the outer expression statement.
 294  *
 295  * The access subexpressions are replaced by the isl_ast_expr
 296  * associated to its reference identifier in "ref2expr".
 297  */
 298 static __isl_take isl_printer *print_pet_expr(__isl_take isl_printer *p,
 299         struct pet_expr *expr, int outer,
 300         __isl_keep isl_id_to_ast_expr *ref2expr)
 301 {
 302         int i;
 303
 304         switch (expr->type) {
 305         case pet_expr_double:
 306                 p = isl_printer_print_str(p, expr->d.s);
 307                 break;
 308         case pet_expr_access:
 309                 p = print_access(p, expr, ref2expr);
 310                 break;
 311         case pet_expr_unary:
 312                 if (!outer)
 313                         p = isl_printer_print_str(p, "(");
 314                 if (!is_postfix(expr->op))
 315                         p = isl_printer_print_str(p, pet_op_str(expr->op));
 316                 p = print_pet_expr(p, expr->args[pet_un_arg], 0, ref2expr);
 317                 if (is_postfix(expr->op))
 318                         p = isl_printer_print_str(p, pet_op_str(expr->op));
 319                 if (!outer)
 320                         p = isl_printer_print_str(p, ")");
 321                 break;
 322         case pet_expr_binary:
 323                 if (!outer)
 324                         p = isl_printer_print_str(p, "(");
 325                 p = print_pet_expr(p, expr->args[pet_bin_lhs], 0,
 326                                         ref2expr);
 327                 p = isl_printer_print_str(p, " ");
 328                 p = isl_printer_print_str(p, pet_op_str(expr->op));
 329                 p = isl_printer_print_str(p, " ");
 330                 p = print_pet_expr(p, expr->args[pet_bin_rhs], 0,
 331                                         ref2expr);
 332                 if (!outer)
 333                         p = isl_printer_print_str(p, ")");
 334                 break;
 335         case pet_expr_ternary:
 336                 if (!outer)
 337                         p = isl_printer_print_str(p, "(");
 338                 p = print_pet_expr(p, expr->args[pet_ter_cond], 0,
 339                                         ref2expr);
 340                 p = isl_printer_print_str(p, " ? ");
 341                 p = print_pet_expr(p, expr->args[pet_ter_true], 0,
 342                                         ref2expr);
 343                 p = isl_printer_print_str(p, " : ");
 344                 p = print_pet_expr(p, expr->args[pet_ter_false], 0,
 345                                         ref2expr);
 346                 if (!outer)
 347                         p = isl_printer_print_str(p, ")");
 348                 break;
 349         case pet_expr_call:
 350                 p = isl_printer_print_str(p, expr->name);
 351                 p = isl_printer_print_str(p, "(");
 352                 for (i = 0; i < expr->n_arg; ++i) {
 353                         if (i)
 354                                 p = isl_printer_print_str(p, ", ");
 355                         p = print_pet_expr(p, expr->args[i], 1, ref2expr);
 356                 }
 357                 p = isl_printer_print_str(p, ")");
 358                 break;
 359         case pet_expr_cast:
 360                 if (!outer)
 361                         p = isl_printer_print_str(p, "(");
 362                 p = isl_printer_print_str(p, "(");
 363                 p = isl_printer_print_str(p, expr->type_name);
 364                 p = isl_printer_print_str(p, ") ");
 365                 p = print_pet_expr(p, expr->args[0], 0, ref2expr);
 366                 if (!outer)
 367                         p = isl_printer_print_str(p, ")");
 368                 break;
 369         }
 370
 371         return p;
 372 }
 373
 374 /* Print "stmt" to "p".
 375  *
 376  * The access expressions in "stmt" are replaced by the isl_ast_expr
 377  * associated to its reference identifier in "ref2expr".
 378  */
 379 __isl_give isl_printer *pet_stmt_print_body(struct pet_stmt *stmt,
 380         __isl_take isl_printer *p, __isl_keep isl_id_to_ast_expr *ref2expr)
 381 {
 382         if (!stmt)
 383                 return isl_printer_free(p);
 384         p = isl_printer_start_line(p);
 385         p = print_pet_expr(p, stmt->body, 1, ref2expr);
 386         p = isl_printer_print_str(p, ";");
 387         p = isl_printer_end_line(p);
 388
 389         return p;
 390 }