gcc/tree-vectorizer.h

   1 /* Loop Vectorization
   2    Copyright (C) 2003, 2004, 2005 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, 59 Temple Place - Suite 330, Boston, MA
  20 02111-1307, 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: unary or binary.  */
  47 enum operation_type {
  48   unary_op = 1,
  49   binary_op
  50 };
  51
  52 /* Define type of available alignment support.  */
  53 enum dr_alignment_support {
  54   dr_unaligned_unsupported,
  55   dr_unaligned_supported,
  56   dr_unaligned_software_pipeline,
  57   dr_aligned
  58 };
  59
  60 /* Define type of def-use cross-iteration cycle.  */
  61 enum vect_def_type {
  62   vect_constant_def,
  63   vect_invariant_def,
  64   vect_loop_def,
  65   vect_induction_def,
  66   vect_reduction_def,
  67   vect_unknown_def_type
  68 };
  69
  70 /* Define verbosity levels.  */
  71 enum verbosity_levels {
  72   REPORT_NONE,
  73   REPORT_VECTORIZED_LOOPS,
  74   REPORT_UNVECTORIZED_LOOPS,
  75   REPORT_ALIGNMENT,
  76   REPORT_BAD_FORM_LOOPS,
  77   REPORT_OUTER_LOOPS,
  78   REPORT_DETAILS,
  79   /* New verbosity levels should be added before this one.  */
  80   MAX_VERBOSITY_LEVEL
  81 };
  82
  83 /*-----------------------------------------------------------------*/
  84 /* Info on vectorized loops.                                       */
  85 /*-----------------------------------------------------------------*/
  86 typedef struct _loop_vec_info {
  87
  88   /* The loop to which this info struct refers to.  */
  89   struct loop *loop;
  90
  91   /* The loop basic blocks.  */
  92   basic_block *bbs;
  93
  94   /* The loop exit_condition.  */
  95   tree exit_cond;
  96
  97   /* Number of iterations.  */
  98   tree num_iters;
  99
 100   /* Is the loop vectorizable? */
 101   bool vectorizable;
 102
 103   /* Unrolling factor  */
 104   int vectorization_factor;
 105
 106   /* Unknown DRs according to which loop was peeled.  */
 107   struct data_reference *unaligned_dr;
 108
 109   /* peeling_for_alignment indicates whether peeling for alignment will take
 110      place, and what the peeling factor should be:
 111      peeling_for_alignment = X means:
 112         If X=0: Peeling for alignment will not be applied.
 113         If X>0: Peel first X iterations.
 114         If X=-1: Generate a runtime test to calculate the number of iterations
 115                  to be peeled, using the dataref recorded in the field
 116                  unaligned_dr.  */
 117   int peeling_for_alignment;
 118
 119   /* All data references in the loop that are being written to.  */
 120   varray_type data_ref_writes;
 121
 122   /* All data references in the loop that are being read from.  */
 123   varray_type data_ref_reads;
 124
 125   /* The loop location in the source.  */
 126   LOC loop_line_number;
 127 } *loop_vec_info;
 128
 129 /* Access Functions.  */
 130 #define LOOP_VINFO_LOOP(L)           (L)->loop
 131 #define LOOP_VINFO_BBS(L)            (L)->bbs
 132 #define LOOP_VINFO_EXIT_COND(L)      (L)->exit_cond
 133 #define LOOP_VINFO_NITERS(L)         (L)->num_iters
 134 #define LOOP_VINFO_VECTORIZABLE_P(L) (L)->vectorizable
 135 #define LOOP_VINFO_VECT_FACTOR(L)    (L)->vectorization_factor
 136 #define LOOP_VINFO_DATAREF_WRITES(L) (L)->data_ref_writes
 137 #define LOOP_VINFO_DATAREF_READS(L)  (L)->data_ref_reads
 138 #define LOOP_VINFO_INT_NITERS(L) (TREE_INT_CST_LOW ((L)->num_iters))
 139 #define LOOP_PEELING_FOR_ALIGNMENT(L) (L)->peeling_for_alignment
 140 #define LOOP_VINFO_UNALIGNED_DR(L) (L)->unaligned_dr
 141 #define LOOP_VINFO_LOC(L)          (L)->loop_line_number
 142
 143 #define LOOP_LOC(L)    LOOP_VINFO_LOC(L)
 144
 145
 146 #define LOOP_VINFO_NITERS_KNOWN_P(L)                     \
 147 (host_integerp ((L)->num_iters,0)                        \
 148 && TREE_INT_CST_LOW ((L)->num_iters) > 0)
 149
 150 /*-----------------------------------------------------------------*/
 151 /* Info on vectorized defs.                                        */
 152 /*-----------------------------------------------------------------*/
 153 enum stmt_vec_info_type {
 154   undef_vec_info_type = 0,
 155   load_vec_info_type,
 156   store_vec_info_type,
 157   op_vec_info_type,
 158   assignment_vec_info_type,
 159   condition_vec_info_type,
 160   reduc_vec_info_type
 161 };
 162
 163 typedef struct data_reference *dr_p;
 164 DEF_VEC_P(dr_p);
 165 DEF_VEC_ALLOC_P(dr_p,heap);
 166
 167 typedef struct _stmt_vec_info {
 168
 169   enum stmt_vec_info_type type;
 170
 171   /* The stmt to which this info struct refers to.  */
 172   tree stmt;
 173
 174   /* The loop_vec_info with respect to which STMT is vectorized.  */
 175   loop_vec_info loop_vinfo;
 176
 177   /* Not all stmts in the loop need to be vectorized. e.g, the incrementation
 178      of the loop induction variable and computation of array indexes. relevant
 179      indicates whether the stmt needs to be vectorized.  */
 180   bool relevant;
 181
 182   /* Indicates whether this stmts is part of a computation whose result is
 183      used outside the loop.  */
 184   bool live;
 185
 186   /* The vector type to be used.  */
 187   tree vectype;
 188
 189   /* The vectorized version of the stmt.  */
 190   tree vectorized_stmt;
 191
 192
 193   /** The following is relevant only for stmts that contain a non-scalar
 194      data-ref (array/pointer/struct access). A GIMPLE stmt is expected to have
 195      at most one such data-ref.  **/
 196
 197   /* Information about the data-ref (access function, etc).  */
 198   struct data_reference *data_ref_info;
 199
 200   /* Aliasing information.  This field represents the symbol that
 201      should be aliased by a pointer holding the address of this data
 202      reference.  If the original data reference was a pointer
 203      dereference, then this field contains the memory tag that should
 204      be used by the new vector-pointer.  */
 205   tree memtag;
 206   struct ptr_info_def *ptr_info;
 207   subvar_t subvars;
 208
 209   /** The following fields are used to store the information about
 210       data-reference. {base_address + initial_offset} is the first location
 211       accessed by data-ref in the loop, and step is the stride of data-ref in
 212       the loop in bytes;
 213       e.g.:
 214
 215                        Example 1                      Example 2
 216       data-ref         a[j].b[i][j]                   a + 4B (a is int*)
 217
 218       base_address     &a                             a
 219       initial_offset   j_0*D_j + i_0*D_i + C          4
 220       step             D_j                            4
 221
 222       data-reference structure info:
 223       base_name        a                              NULL
 224       access_fn        <access_fns of indexes of b>   (0, +, 1)
 225
 226   **/
 227   /* The above base_address, offset and step.  */
 228   tree base_address;
 229   tree initial_offset;
 230   tree step;
 231
 232   /* Alignment information. Whether the base of the data-reference is aligned
 233      to vectype.  */
 234   bool base_aligned_p;
 235   /* Alignment information. The offset of the data-reference from its base
 236      in bytes.  */
 237   tree misalignment;
 238
 239   /* List of datarefs that are known to have the same alignment as the dataref
 240      of this stmt.  */
 241   VEC(dr_p,heap) *same_align_refs;
 242
 243   /* Classify the def of this stmt.  */
 244   enum vect_def_type def_type;
 245
 246 } *stmt_vec_info;
 247
 248 /* Access Functions.  */
 249 #define STMT_VINFO_TYPE(S)                (S)->type
 250 #define STMT_VINFO_STMT(S)                (S)->stmt
 251 #define STMT_VINFO_LOOP_VINFO(S)          (S)->loop_vinfo
 252 #define STMT_VINFO_RELEVANT_P(S)          (S)->relevant
 253 #define STMT_VINFO_LIVE_P(S)              (S)->live
 254 #define STMT_VINFO_VECTYPE(S)             (S)->vectype
 255 #define STMT_VINFO_VEC_STMT(S)            (S)->vectorized_stmt
 256 #define STMT_VINFO_DATA_REF(S)            (S)->data_ref_info
 257 #define STMT_VINFO_MEMTAG(S)              (S)->memtag
 258 #define STMT_VINFO_PTR_INFO(S)            (S)->ptr_info
 259 #define STMT_VINFO_SUBVARS(S)             (S)->subvars
 260 #define STMT_VINFO_VECT_DR_BASE_ADDRESS(S)(S)->base_address
 261 #define STMT_VINFO_VECT_INIT_OFFSET(S)    (S)->initial_offset
 262 #define STMT_VINFO_VECT_STEP(S)           (S)->step
 263 #define STMT_VINFO_VECT_BASE_ALIGNED_P(S) (S)->base_aligned_p
 264 #define STMT_VINFO_VECT_MISALIGNMENT(S)   (S)->misalignment
 265 #define STMT_VINFO_SAME_ALIGN_REFS(S)     (S)->same_align_refs
 266 #define STMT_VINFO_DEF_TYPE(S)            (S)->def_type
 267
 268 static inline void set_stmt_info (tree_ann_t ann, stmt_vec_info stmt_info);
 269 static inline stmt_vec_info vinfo_for_stmt (tree stmt);
 270
 271 static inline void
 272 set_stmt_info (tree_ann_t ann, stmt_vec_info stmt_info)
 273 {
 274   if (ann)
 275     ann->common.aux = (char *) stmt_info;
 276 }
 277
 278 static inline stmt_vec_info
 279 vinfo_for_stmt (tree stmt)
 280 {
 281   tree_ann_t ann = tree_ann (stmt);
 282   return ann ? (stmt_vec_info) ann->common.aux : NULL;
 283 }
 284
 285 /*-----------------------------------------------------------------*/
 286 /* Info on data references alignment.                              */
 287 /*-----------------------------------------------------------------*/
 288
 289 /* Reflects actual alignment of first access in the vectorized loop,
 290    taking into account peeling/versioning if applied.  */
 291 #define DR_MISALIGNMENT(DR)   (DR)->aux
 292
 293 static inline bool
 294 aligned_access_p (struct data_reference *data_ref_info)
 295 {
 296   return (DR_MISALIGNMENT (data_ref_info) == 0);
 297 }
 298
 299 static inline bool
 300 known_alignment_for_access_p (struct data_reference *data_ref_info)
 301 {
 302   return (DR_MISALIGNMENT (data_ref_info) != -1);
 303 }
 304
 305 /* Perform signed modulo, always returning a non-negative value.  */
 306 #define VECT_SMODULO(x,y) ((x) % (y) < 0 ? ((x) % (y) + (y)) : (x) % (y))
 307
 308 /* vect_dump will be set to stderr or dump_file if exist.  */
 309 extern FILE *vect_dump;
 310 extern enum verbosity_levels vect_verbosity_level;
 311
 312 /* Number of loops, at the beginning of vectorization.  */
 313 extern unsigned int vect_loops_num;
 314 /*-----------------------------------------------------------------*/
 315 /* Function prototypes.                                            */
 316 /*-----------------------------------------------------------------*/
 317
 318 /*************************************************************************
 319   Simple Loop Peeling Utilities - in tree-vectorizer.c
 320  *************************************************************************/
 321 /* Entry point for peeling of simple loops.
 322    Peel the first/last iterations of a loop.
 323    It can be used outside of the vectorizer for loops that are simple enough
 324    (see function documentation).  In the vectorizer it is used to peel the
 325    last few iterations when the loop bound is unknown or does not evenly
 326    divide by the vectorization factor, and to peel the first few iterations
 327    to force the alignment of data references in the loop.  */
 328 extern struct loop *slpeel_tree_peel_loop_to_edge
 329   (struct loop *, struct loops *, edge, tree, tree, bool);
 330 extern void slpeel_make_loop_iterate_ntimes (struct loop *, tree);
 331 extern bool slpeel_can_duplicate_loop_p (struct loop *, edge);
 332 #ifdef ENABLE_CHECKING
 333 extern void slpeel_verify_cfg_after_peeling (struct loop *, struct loop *);
 334 #endif
 335
 336
 337 /*************************************************************************
 338   General Vectorization Utilities
 339  *************************************************************************/
 340 /** In tree-vectorizer.c **/
 341 extern tree vect_strip_conversion (tree);
 342 extern tree get_vectype_for_scalar_type (tree);
 343 extern bool vect_is_simple_use (tree, loop_vec_info, tree *, tree *,
 344                                 enum vect_def_type *);
 345 extern bool vect_is_simple_iv_evolution (unsigned, tree, tree *, tree *);
 346 extern tree vect_is_simple_reduction (struct loop *, tree);
 347 extern bool vect_can_force_dr_alignment_p (tree, unsigned int);
 348 extern enum dr_alignment_support vect_supportable_dr_alignment
 349   (struct data_reference *);
 350 extern bool reduction_code_for_scalar_code (enum tree_code, enum tree_code *);
 351
 352 /* Creation and deletion of loop and stmt info structs.  */
 353 extern loop_vec_info new_loop_vec_info (struct loop *loop);
 354 extern void destroy_loop_vec_info (loop_vec_info);
 355 extern stmt_vec_info new_stmt_vec_info (tree stmt, loop_vec_info);
 356 /* Main driver.  */
 357 extern void vectorize_loops (struct loops *);
 358
 359 /** In tree-vect-analyze.c  **/
 360 /* Driver for analysis stage.  */
 361 extern loop_vec_info vect_analyze_loop (struct loop *);
 362
 363 /** In tree-vect-transform.c  **/
 364 extern bool vectorizable_load (tree, block_stmt_iterator *, tree *);
 365 extern bool vectorizable_store (tree, block_stmt_iterator *, tree *);
 366 extern bool vectorizable_operation (tree, block_stmt_iterator *, tree *);
 367 extern bool vectorizable_assignment (tree, block_stmt_iterator *, tree *);
 368 extern bool vectorizable_condition (tree, block_stmt_iterator *, tree *);
 369 extern bool vectorizable_live_operation (tree, block_stmt_iterator *, tree *);
 370 extern bool vectorizable_reduction (tree, block_stmt_iterator *, tree *);
 371 /* Driver for transformation stage.  */
 372 extern void vect_transform_loop (loop_vec_info, struct loops *);
 373
 374 /*************************************************************************
 375   Vectorization Debug Information - in tree-vectorizer.c
 376  *************************************************************************/
 377 extern bool vect_print_dump_info (enum verbosity_levels, LOC);
 378 extern void vect_set_verbosity_level (const char *);
 379 extern LOC find_loop_location (struct loop *);
 380
 381 #endif  /* GCC_TREE_VECTORIZER_H  */