gcc/tree-vectorizer.h

   1 /* Loop Vectorization
   2    Copyright (C) 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc.
   3    Contributed by Dorit Naishlos <dorit@il.ibm.com>
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 2, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING.  If not, write to the Free
  19 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
  20 02110-1301, USA.  */
  21
  22 #ifndef GCC_TREE_VECTORIZER_H
  23 #define GCC_TREE_VECTORIZER_H
  24
  25 #ifdef USE_MAPPED_LOCATION
  26   typedef source_location LOC;
  27   #define UNKNOWN_LOC UNKNOWN_LOCATION
  28   #define EXPR_LOC(e) EXPR_LOCATION(e)
  29   #define LOC_FILE(l) LOCATION_FILE (l)
  30   #define LOC_LINE(l) LOCATION_LINE (l)
  31 #else
  32   typedef source_locus LOC;
  33   #define UNKNOWN_LOC NULL
  34   #define EXPR_LOC(e) EXPR_LOCUS(e)
  35   #define LOC_FILE(l) (l)->file
  36   #define LOC_LINE(l) (l)->line
  37 #endif
  38
  39 /* Used for naming of new temporaries.  */
  40 enum vect_var_kind {
  41   vect_simple_var,
  42   vect_pointer_var,
  43   vect_scalar_var
  44 };
  45
  46 /* Defines type of operation.  */
  47 enum operation_type {
  48   unary_op = 1,
  49   binary_op,
  50   ternary_op
  51 };
  52
  53 /* Define type of available alignment support.  */
  54 enum dr_alignment_support {
  55   dr_unaligned_unsupported,
  56   dr_unaligned_supported,
  57   dr_unaligned_software_pipeline,
  58   dr_aligned
  59 };
  60
  61 /* Define type of def-use cross-iteration cycle.  */
  62 enum vect_def_type {
  63   vect_constant_def,
  64   vect_invariant_def,
  65   vect_loop_def,
  66   vect_induction_def,
  67   vect_reduction_def,
  68   vect_unknown_def_type
  69 };
  70
  71 /* Define verbosity levels.  */
  72 enum verbosity_levels {
  73   REPORT_NONE,
  74   REPORT_VECTORIZED_LOOPS,
  75   REPORT_UNVECTORIZED_LOOPS,
  76   REPORT_ALIGNMENT,
  77   REPORT_DR_DETAILS,
  78   REPORT_BAD_FORM_LOOPS,
  79   REPORT_OUTER_LOOPS,
  80   REPORT_DETAILS,
  81   /* New verbosity levels should be added before this one.  */
  82   MAX_VERBOSITY_LEVEL
  83 };
  84
  85 /*-----------------------------------------------------------------*/
  86 /* Info on vectorized loops.                                       */
  87 /*-----------------------------------------------------------------*/
  88 typedef struct _loop_vec_info {
  89
  90   /* The loop to which this info struct refers to.  */
  91   struct loop *loop;
  92
  93   /* The loop basic blocks.  */
  94   basic_block *bbs;
  95
  96   /* The loop exit_condition.  */
  97   tree exit_cond;
  98
  99   /* Number of iterations.  */
 100   tree num_iters;
 101
 102   /* Is the loop vectorizable? */
 103   bool vectorizable;
 104
 105   /* Unrolling factor  */
 106   int vectorization_factor;
 107
 108   /* Unknown DRs according to which loop was peeled.  */
 109   struct data_reference *unaligned_dr;
 110
 111   /* peeling_for_alignment indicates whether peeling for alignment will take
 112      place, and what the peeling factor should be:
 113      peeling_for_alignment = X means:
 114         If X=0: Peeling for alignment will not be applied.
 115         If X>0: Peel first X iterations.
 116         If X=-1: Generate a runtime test to calculate the number of iterations
 117                  to be peeled, using the dataref recorded in the field
 118                  unaligned_dr.  */
 119   int peeling_for_alignment;
 120
 121   /* The mask used to check the alignment of pointers or arrays.  */
 122   int ptr_mask;
 123
 124   /* All data references in the loop.  */
 125   VEC (data_reference_p, heap) *datarefs;
 126
 127   /* All data dependences in the loop.  */
 128   VEC (ddr_p, heap) *ddrs;
 129
 130   /* Statements in the loop that have data references that are candidates for a
 131      runtime (loop versioning) misalignment check.  */
 132   VEC(tree,heap) *may_misalign_stmts;
 133
 134   /* The loop location in the source.  */
 135   LOC loop_line_number;
 136 } *loop_vec_info;
 137
 138 /* Access Functions.  */
 139 #define LOOP_VINFO_LOOP(L)            (L)->loop
 140 #define LOOP_VINFO_BBS(L)             (L)->bbs
 141 #define LOOP_VINFO_EXIT_COND(L)       (L)->exit_cond
 142 #define LOOP_VINFO_NITERS(L)          (L)->num_iters
 143 #define LOOP_VINFO_VECTORIZABLE_P(L)  (L)->vectorizable
 144 #define LOOP_VINFO_VECT_FACTOR(L)     (L)->vectorization_factor
 145 #define LOOP_VINFO_PTR_MASK(L)        (L)->ptr_mask
 146 #define LOOP_VINFO_DATAREFS(L)        (L)->datarefs
 147 #define LOOP_VINFO_DDRS(L)            (L)->ddrs
 148 #define LOOP_VINFO_INT_NITERS(L)      (TREE_INT_CST_LOW ((L)->num_iters))
 149 #define LOOP_PEELING_FOR_ALIGNMENT(L) (L)->peeling_for_alignment
 150 #define LOOP_VINFO_UNALIGNED_DR(L)    (L)->unaligned_dr
 151 #define LOOP_VINFO_MAY_MISALIGN_STMTS(L) (L)->may_misalign_stmts
 152 #define LOOP_VINFO_LOC(L)             (L)->loop_line_number
 153
 154 #define NITERS_KNOWN_P(n)                     \
 155 (host_integerp ((n),0)                        \
 156 && TREE_INT_CST_LOW ((n)) > 0)
 157
 158 #define LOOP_VINFO_NITERS_KNOWN_P(L)                     \
 159 NITERS_KNOWN_P((L)->num_iters)
 160
 161 /*-----------------------------------------------------------------*/
 162 /* Info on vectorized defs.                                        */
 163 /*-----------------------------------------------------------------*/
 164 enum stmt_vec_info_type {
 165   undef_vec_info_type = 0,
 166   load_vec_info_type,
 167   store_vec_info_type,
 168   op_vec_info_type,
 169   call_vec_info_type,
 170   assignment_vec_info_type,
 171   condition_vec_info_type,
 172   reduc_vec_info_type,
 173   induc_vec_info_type,
 174   type_promotion_vec_info_type,
 175   type_demotion_vec_info_type,
 176   type_conversion_vec_info_type
 177 };
 178
 179 /* Indicates whether/how a variable is used in the loop.  */
 180 enum vect_relevant {
 181   vect_unused_in_loop = 0,
 182
 183   /* defs that feed computations that end up (only) in a reduction. These
 184      defs may be used by non-reduction stmts, but eventually, any
 185      computations/values that are affected by these defs are used to compute
 186      a reduction (i.e. don't get stored to memory, for example). We use this
 187      to identify computations that we can change the order in which they are
 188      computed.  */
 189   vect_used_by_reduction,
 190
 191   vect_used_in_loop
 192 };
 193
 194 typedef struct data_reference *dr_p;
 195 DEF_VEC_P(dr_p);
 196 DEF_VEC_ALLOC_P(dr_p,heap);
 197
 198 typedef struct _stmt_vec_info {
 199
 200   enum stmt_vec_info_type type;
 201
 202   /* The stmt to which this info struct refers to.  */
 203   tree stmt;
 204
 205   /* The loop_vec_info with respect to which STMT is vectorized.  */
 206   loop_vec_info loop_vinfo;
 207
 208   /* Not all stmts in the loop need to be vectorized. e.g, the increment
 209      of the loop induction variable and computation of array indexes. relevant
 210      indicates whether the stmt needs to be vectorized.  */
 211   enum vect_relevant relevant;
 212
 213   /* Indicates whether this stmts is part of a computation whose result is
 214      used outside the loop.  */
 215   bool live;
 216
 217   /* The vector type to be used.  */
 218   tree vectype;
 219
 220   /* The vectorized version of the stmt.  */
 221   tree vectorized_stmt;
 222
 223
 224   /** The following is relevant only for stmts that contain a non-scalar
 225      data-ref (array/pointer/struct access). A GIMPLE stmt is expected to have
 226      at most one such data-ref.  **/
 227
 228   /* Information about the data-ref (access function, etc).  */
 229   struct data_reference *data_ref_info;
 230
 231   /* Stmt is part of some pattern (computation idiom)  */
 232   bool in_pattern_p;
 233
 234   /* Used for various bookkeeping purposes, generally holding a pointer to
 235      some other stmt S that is in some way "related" to this stmt.
 236      Current use of this field is:
 237         If this stmt is part of a pattern (i.e. the field 'in_pattern_p' is
 238         true): S is the "pattern stmt" that represents (and replaces) the
 239         sequence of stmts that constitutes the pattern.  Similarly, the
 240         related_stmt of the "pattern stmt" points back to this stmt (which is
 241         the last stmt in the original sequence of stmts that constitutes the
 242         pattern).  */
 243   tree related_stmt;
 244
 245   /* List of datarefs that are known to have the same alignment as the dataref
 246      of this stmt.  */
 247   VEC(dr_p,heap) *same_align_refs;
 248
 249   /* Classify the def of this stmt.  */
 250   enum vect_def_type def_type;
 251
 252   /* Interleaving info.  */
 253   /* First data-ref in the interleaving group.  */
 254   tree first_dr;
 255   /* Pointer to the next data-ref in the group.  */
 256   tree next_dr;
 257   /* The size of the interleaving group.  */
 258   unsigned int size;
 259   /* For stores, number of stores from this group seen. We vectorize the last
 260      one.  */
 261   unsigned int store_count;
 262   /* For loads only, the gap from the previous load. For consecutive loads, GAP
 263      is 1.  */
 264   unsigned int gap;
 265   /* In case that two or more stmts share data-ref, this is the pointer to the
 266      previously detected stmt with the same dr.  */
 267   tree same_dr_stmt;
 268   /* For loads only, if there is a store with the same location, this field is
 269      TRUE.  */
 270   bool read_write_dep;
 271
 272   /* Vectorization costs associated with statement.  */
 273   struct
 274   {
 275     int outside_of_loop;     /* Statements generated outside loop.  */
 276     int inside_of_loop;      /* Statements generated inside loop.  */
 277   } cost;
 278 } *stmt_vec_info;
 279
 280 /* Access Functions.  */
 281 #define STMT_VINFO_TYPE(S)                 (S)->type
 282 #define STMT_VINFO_STMT(S)                 (S)->stmt
 283 #define STMT_VINFO_LOOP_VINFO(S)           (S)->loop_vinfo
 284 #define STMT_VINFO_RELEVANT(S)             (S)->relevant
 285 #define STMT_VINFO_LIVE_P(S)               (S)->live
 286 #define STMT_VINFO_VECTYPE(S)              (S)->vectype
 287 #define STMT_VINFO_VEC_STMT(S)             (S)->vectorized_stmt
 288 #define STMT_VINFO_DATA_REF(S)             (S)->data_ref_info
 289 #define STMT_VINFO_IN_PATTERN_P(S)         (S)->in_pattern_p
 290 #define STMT_VINFO_RELATED_STMT(S)         (S)->related_stmt
 291 #define STMT_VINFO_SAME_ALIGN_REFS(S)      (S)->same_align_refs
 292 #define STMT_VINFO_DEF_TYPE(S)             (S)->def_type
 293 #define STMT_VINFO_DR_GROUP_FIRST_DR(S)    (S)->first_dr
 294 #define STMT_VINFO_DR_GROUP_NEXT_DR(S)     (S)->next_dr
 295 #define STMT_VINFO_DR_GROUP_SIZE(S)        (S)->size
 296 #define STMT_VINFO_DR_GROUP_STORE_COUNT(S) (S)->store_count
 297 #define STMT_VINFO_DR_GROUP_GAP(S)         (S)->gap
 298 #define STMT_VINFO_DR_GROUP_SAME_DR_STMT(S)(S)->same_dr_stmt
 299 #define STMT_VINFO_DR_GROUP_READ_WRITE_DEPENDENCE(S)  (S)->read_write_dep
 300
 301 #define DR_GROUP_FIRST_DR(S)               (S)->first_dr
 302 #define DR_GROUP_NEXT_DR(S)                (S)->next_dr
 303 #define DR_GROUP_SIZE(S)                   (S)->size
 304 #define DR_GROUP_STORE_COUNT(S)            (S)->store_count
 305 #define DR_GROUP_GAP(S)                    (S)->gap
 306 #define DR_GROUP_SAME_DR_STMT(S)           (S)->same_dr_stmt
 307 #define DR_GROUP_READ_WRITE_DEPENDENCE(S)  (S)->read_write_dep
 308
 309 #define STMT_VINFO_RELEVANT_P(S)          ((S)->relevant != vect_unused_in_loop)
 310 #define STMT_VINFO_OUTSIDE_OF_LOOP_COST(S) (S)->cost.outside_of_loop
 311 #define STMT_VINFO_INSIDE_OF_LOOP_COST(S)  (S)->cost.inside_of_loop
 312
 313 /* These are some defines for the initial implementation of the vectorizer's
 314    cost model.  These will later be target specific hooks.  */
 315
 316 /* Cost of conditional branch.  */
 317 #ifndef TARG_COND_BRANCH_COST
 318 #define TARG_COND_BRANCH_COST        3
 319 #endif
 320
 321 /* Cost of any vector operation, excluding load, store or vector to scalar
 322    operation.  */
 323 #ifndef TARG_VEC_STMT_COST
 324 #define TARG_VEC_STMT_COST           1
 325 #endif
 326
 327 /* Cost of vector to scalar operation.  */
 328 #ifndef TARG_VEC_TO_SCALAR_COST
 329 #define TARG_VEC_TO_SCALAR_COST      1
 330 #endif
 331
 332 /* Cost of aligned vector load.  */
 333 #ifndef TARG_VEC_LOAD_COST
 334 #define TARG_VEC_LOAD_COST           1
 335 #endif
 336
 337 /* Cost of misaligned vector load.  */
 338 #ifndef TARG_VEC_UNALIGNED_LOAD_COST
 339 #define TARG_VEC_UNALIGNED_LOAD_COST 2
 340 #endif
 341
 342 /* Cost of vector store.  */
 343 #ifndef TARG_VEC_STORE_COST
 344 #define TARG_VEC_STORE_COST          1
 345 #endif
 346
 347 static inline void set_stmt_info (stmt_ann_t ann, stmt_vec_info stmt_info);
 348 static inline stmt_vec_info vinfo_for_stmt (tree stmt);
 349
 350 static inline void
 351 set_stmt_info (stmt_ann_t ann, stmt_vec_info stmt_info)
 352 {
 353   if (ann)
 354     ann->common.aux = (char *) stmt_info;
 355 }
 356
 357 static inline stmt_vec_info
 358 vinfo_for_stmt (tree stmt)
 359 {
 360   stmt_ann_t ann = stmt_ann (stmt);
 361   return ann ? (stmt_vec_info) ann->common.aux : NULL;
 362 }
 363
 364 static inline bool
 365 is_pattern_stmt_p (stmt_vec_info stmt_info)
 366 {
 367   tree related_stmt;
 368   stmt_vec_info related_stmt_info;
 369
 370   related_stmt = STMT_VINFO_RELATED_STMT (stmt_info);
 371   if (related_stmt
 372       && (related_stmt_info = vinfo_for_stmt (related_stmt))
 373       && STMT_VINFO_IN_PATTERN_P (related_stmt_info))
 374     return true;
 375
 376   return false;
 377 }
 378
 379 /*-----------------------------------------------------------------*/
 380 /* Info on data references alignment.                              */
 381 /*-----------------------------------------------------------------*/
 382
 383 /* Reflects actual alignment of first access in the vectorized loop,
 384    taking into account peeling/versioning if applied.  */
 385 #define DR_MISALIGNMENT(DR)   ((int) (size_t) (DR)->aux)
 386 #define SET_DR_MISALIGNMENT(DR, VAL)   ((DR)->aux = (void *) (size_t) (VAL))
 387
 388 static inline bool
 389 aligned_access_p (struct data_reference *data_ref_info)
 390 {
 391   return (DR_MISALIGNMENT (data_ref_info) == 0);
 392 }
 393
 394 static inline bool
 395 known_alignment_for_access_p (struct data_reference *data_ref_info)
 396 {
 397   return (DR_MISALIGNMENT (data_ref_info) != -1);
 398 }
 399
 400 /* vect_dump will be set to stderr or dump_file if exist.  */
 401 extern FILE *vect_dump;
 402 extern enum verbosity_levels vect_verbosity_level;
 403
 404 /* Bitmap of virtual variables to be renamed.  */
 405 extern bitmap vect_memsyms_to_rename;
 406
 407 /*-----------------------------------------------------------------*/
 408 /* Function prototypes.                                            */
 409 /*-----------------------------------------------------------------*/
 410
 411 /*************************************************************************
 412   Simple Loop Peeling Utilities - in tree-vectorizer.c
 413  *************************************************************************/
 414 /* Entry point for peeling of simple loops.
 415    Peel the first/last iterations of a loop.
 416    It can be used outside of the vectorizer for loops that are simple enough
 417    (see function documentation).  In the vectorizer it is used to peel the
 418    last few iterations when the loop bound is unknown or does not evenly
 419    divide by the vectorization factor, and to peel the first few iterations
 420    to force the alignment of data references in the loop.  */
 421 extern struct loop *slpeel_tree_peel_loop_to_edge
 422   (struct loop *, edge, tree, tree, bool, unsigned int);
 423 extern void slpeel_make_loop_iterate_ntimes (struct loop *, tree);
 424 extern bool slpeel_can_duplicate_loop_p (struct loop *, edge);
 425 #ifdef ENABLE_CHECKING
 426 extern void slpeel_verify_cfg_after_peeling (struct loop *, struct loop *);
 427 #endif
 428
 429
 430 /*************************************************************************
 431   General Vectorization Utilities
 432  *************************************************************************/
 433 /** In tree-vectorizer.c **/
 434 extern tree get_vectype_for_scalar_type (tree);
 435 extern bool vect_is_simple_use (tree, loop_vec_info, tree *, tree *,
 436                                 enum vect_def_type *);
 437 extern bool vect_is_simple_iv_evolution (unsigned, tree, tree *, tree *);
 438 extern tree vect_is_simple_reduction (struct loop *, tree);
 439 extern bool vect_can_force_dr_alignment_p (tree, unsigned int);
 440 extern enum dr_alignment_support vect_supportable_dr_alignment
 441   (struct data_reference *);
 442 extern bool reduction_code_for_scalar_code (enum tree_code, enum tree_code *);
 443 extern bool supportable_widening_operation (enum tree_code, tree, tree,
 444   tree *, tree *, enum tree_code *, enum tree_code *);
 445 extern bool supportable_narrowing_operation (enum tree_code, tree, tree,
 446                                              enum tree_code *);
 447
 448 /* Creation and deletion of loop and stmt info structs.  */
 449 extern loop_vec_info new_loop_vec_info (struct loop *loop);
 450 extern void destroy_loop_vec_info (loop_vec_info);
 451 extern stmt_vec_info new_stmt_vec_info (tree stmt, loop_vec_info);
 452
 453
 454 /** In tree-vect-analyze.c  **/
 455 /* Driver for analysis stage.  */
 456 extern loop_vec_info vect_analyze_loop (struct loop *);
 457
 458
 459 /** In tree-vect-patterns.c  **/
 460 /* Pattern recognition functions.
 461    Additional pattern recognition functions can (and will) be added
 462    in the future.  */
 463 typedef tree (* vect_recog_func_ptr) (tree, tree *, tree *);
 464 #define NUM_PATTERNS 4
 465 void vect_pattern_recog (loop_vec_info);
 466
 467
 468 /** In tree-vect-transform.c  **/
 469 extern bool vectorizable_load (tree, block_stmt_iterator *, tree *);
 470 extern bool vectorizable_store (tree, block_stmt_iterator *, tree *);
 471 extern bool vectorizable_operation (tree, block_stmt_iterator *, tree *);
 472 extern bool vectorizable_type_promotion (tree, block_stmt_iterator *, tree *);
 473 extern bool vectorizable_type_demotion (tree, block_stmt_iterator *, tree *);
 474 extern bool vectorizable_conversion (tree, block_stmt_iterator *,
 475                                      tree *);
 476 extern bool vectorizable_assignment (tree, block_stmt_iterator *, tree *);
 477 extern tree vectorizable_function (tree, tree, tree);
 478 extern bool vectorizable_call (tree, block_stmt_iterator *, tree *);
 479 extern bool vectorizable_condition (tree, block_stmt_iterator *, tree *);
 480 extern bool vectorizable_live_operation (tree, block_stmt_iterator *, tree *);
 481 extern bool vectorizable_reduction (tree, block_stmt_iterator *, tree *);
 482 extern bool vectorizable_induction (tree, block_stmt_iterator *, tree *);
 483 extern int  vect_estimate_min_profitable_iters (loop_vec_info);
 484 /* Driver for transformation stage.  */
 485 extern void vect_transform_loop (loop_vec_info);
 486
 487 /*************************************************************************
 488   Vectorization Debug Information - in tree-vectorizer.c
 489  *************************************************************************/
 490 extern bool vect_print_dump_info (enum verbosity_levels);
 491 extern void vect_set_verbosity_level (const char *);
 492 extern LOC find_loop_location (struct loop *);
 493
 494 #endif  /* GCC_TREE_VECTORIZER_H  */