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 };
  44
  45 /* Defines type of operation: unary or binary.  */
  46 enum operation_type {
  47   unary_op = 1,
  48   binary_op
  49 };
  50
  51 /* Define type of available alignment support.  */
  52 enum dr_alignment_support {
  53   dr_unaligned_unsupported,
  54   dr_unaligned_supported,
  55   dr_unaligned_software_pipeline,
  56   dr_aligned
  57 };
  58
  59 /* Define type of def-use cross-iteration cycle.  */
  60 enum vect_def_type {
  61   vect_constant_def,
  62   vect_invariant_def,
  63   vect_loop_def,
  64   vect_induction_def,
  65   vect_reduction_def,
  66   vect_unknown_def_type
  67 };
  68
  69 /* Define verbosity levels.  */
  70 enum verbosity_levels {
  71   REPORT_NONE,
  72   REPORT_VECTORIZED_LOOPS,
  73   REPORT_UNVECTORIZED_LOOPS,
  74   REPORT_ALIGNMENT,
  75   REPORT_BAD_FORM_LOOPS,
  76   REPORT_OUTER_LOOPS,
  77   REPORT_DETAILS,
  78   /* New verbosity levels should be added before this one.  */
  79   MAX_VERBOSITY_LEVEL
  80 };
  81
  82 /*-----------------------------------------------------------------*/
  83 /* Info on vectorized loops.                                       */
  84 /*-----------------------------------------------------------------*/
  85 typedef struct _loop_vec_info {
  86
  87   /* The loop to which this info struct refers to.  */
  88   struct loop *loop;
  89
  90   /* The loop basic blocks.  */
  91   basic_block *bbs;
  92
  93   /* The loop exit_condition.  */
  94   tree exit_cond;
  95
  96   /* Number of iterations.  */
  97   tree num_iters;
  98
  99   /* Is the loop vectorizable? */
 100   bool vectorizable;
 101
 102   /* Unrolling factor  */
 103   int vectorization_factor;
 104
 105   /* Unknown DRs according to which loop was peeled.  */
 106   struct data_reference *unaligned_dr;
 107
 108   /* peeling_for_alignment indicates whether peeling for alignment will take
 109      place, and what the peeling factor should be:
 110      peeling_for_alignment = X means:
 111         If X=0: Peeling for alignment will not be applied.
 112         If X>0: Peel first X iterations.
 113         If X=-1: Generate a runtime test to calculate the number of iterations
 114                  to be peeled, using the dataref recorded in the field
 115                  unaligned_dr.  */
 116   int peeling_for_alignment;
 117
 118   /* All data references in the loop that are being written to.  */
 119   varray_type data_ref_writes;
 120
 121   /* All data references in the loop that are being read from.  */
 122   varray_type data_ref_reads;
 123
 124   /* The loop location in the source.  */
 125   LOC loop_line_number;
 126 } *loop_vec_info;
 127
 128 /* Access Functions.  */
 129 #define LOOP_VINFO_LOOP(L)           (L)->loop
 130 #define LOOP_VINFO_BBS(L)            (L)->bbs
 131 #define LOOP_VINFO_EXIT_COND(L)      (L)->exit_cond
 132 #define LOOP_VINFO_NITERS(L)         (L)->num_iters
 133 #define LOOP_VINFO_VECTORIZABLE_P(L) (L)->vectorizable
 134 #define LOOP_VINFO_VECT_FACTOR(L)    (L)->vectorization_factor
 135 #define LOOP_VINFO_DATAREF_WRITES(L) (L)->data_ref_writes
 136 #define LOOP_VINFO_DATAREF_READS(L)  (L)->data_ref_reads
 137 #define LOOP_VINFO_INT_NITERS(L) (TREE_INT_CST_LOW ((L)->num_iters))
 138 #define LOOP_PEELING_FOR_ALIGNMENT(L) (L)->peeling_for_alignment
 139 #define LOOP_VINFO_UNALIGNED_DR(L) (L)->unaligned_dr
 140 #define LOOP_VINFO_LOC(L)          (L)->loop_line_number
 141
 142 #define LOOP_LOC(L)    LOOP_VINFO_LOC(L)
 143
 144
 145 #define LOOP_VINFO_NITERS_KNOWN_P(L)                     \
 146 (host_integerp ((L)->num_iters,0)                        \
 147 && TREE_INT_CST_LOW ((L)->num_iters) > 0)
 148
 149 /*-----------------------------------------------------------------*/
 150 /* Info on vectorized defs.                                        */
 151 /*-----------------------------------------------------------------*/
 152 enum stmt_vec_info_type {
 153   undef_vec_info_type = 0,
 154   load_vec_info_type,
 155   store_vec_info_type,
 156   op_vec_info_type,
 157   assignment_vec_info_type,
 158   condition_vec_info_type
 159 };
 160
 161 typedef struct data_reference *dr_p;
 162 DEF_VEC_P(dr_p);
 163 DEF_VEC_ALLOC_P(dr_p,heap);
 164
 165 typedef struct _stmt_vec_info {
 166
 167   enum stmt_vec_info_type type;
 168
 169   /* The stmt to which this info struct refers to.  */
 170   tree stmt;
 171
 172   /* The loop_vec_info with respect to which STMT is vectorized.  */
 173   loop_vec_info loop_vinfo;
 174
 175   /* Not all stmts in the loop need to be vectorized. e.g, the incrementation
 176      of the loop induction variable and computation of array indexes. relevant
 177      indicates whether the stmt needs to be vectorized.  */
 178   bool relevant;
 179
 180   /* Indicates whether this stmts is part of a computation whose result is
 181      used outside the loop.  */
 182   bool live;
 183
 184   /* The vector type to be used.  */
 185   tree vectype;
 186
 187   /* The vectorized version of the stmt.  */
 188   tree vectorized_stmt;
 189
 190
 191   /** The following is relevant only for stmts that contain a non-scalar
 192      data-ref (array/pointer/struct access). A GIMPLE stmt is expected to have
 193      at most one such data-ref.  **/
 194
 195   /* Information about the data-ref (access function, etc).  */
 196   struct data_reference *data_ref_info;
 197
 198   /* Aliasing information.  This field represents the symbol that
 199      should be aliased by a pointer holding the address of this data
 200      reference.  If the original data reference was a pointer
 201      dereference, then this field contains the memory tag that should
 202      be used by the new vector-pointer.  */
 203   tree memtag;
 204   struct ptr_info_def *ptr_info;
 205   subvar_t subvars;
 206
 207   /** The following fields are used to store the information about
 208       data-reference. {base_address + initial_offset} is the first location
 209       accessed by data-ref in the loop, and step is the stride of data-ref in
 210       the loop in bytes;
 211       e.g.:
 212
 213                        Example 1                      Example 2
 214       data-ref         a[j].b[i][j]                   a + 4B (a is int*)
 215
 216       base_address     &a                             a
 217       initial_offset   j_0*D_j + i_0*D_i + C          4
 218       step             D_j                            4
 219
 220       data-reference structure info:
 221       base_name        a                              NULL
 222       access_fn        <access_fns of indexes of b>   (0, +, 1)
 223
 224   **/
 225   /* The above base_address, offset and step.  */
 226   tree base_address;
 227   tree initial_offset;
 228   tree step;
 229
 230   /* Alignment information. Whether the base of the data-reference is aligned
 231      to vectype.  */
 232   bool base_aligned_p;
 233   /* Alignment information. The offset of the data-reference from its base
 234      in bytes.  */
 235   tree misalignment;
 236
 237   /* List of datarefs that are known to have the same alignment as the dataref
 238      of this stmt.  */
 239   VEC(dr_p,heap) *same_align_refs;
 240
 241   /* Classify the def of this stmt.  */
 242   enum vect_def_type def_type;
 243
 244 } *stmt_vec_info;
 245
 246 /* Access Functions.  */
 247 #define STMT_VINFO_TYPE(S)                (S)->type
 248 #define STMT_VINFO_STMT(S)                (S)->stmt
 249 #define STMT_VINFO_LOOP_VINFO(S)          (S)->loop_vinfo
 250 #define STMT_VINFO_RELEVANT_P(S)          (S)->relevant
 251 #define STMT_VINFO_LIVE_P(S)              (S)->live
 252 #define STMT_VINFO_VECTYPE(S)             (S)->vectype
 253 #define STMT_VINFO_VEC_STMT(S)            (S)->vectorized_stmt
 254 #define STMT_VINFO_DATA_REF(S)            (S)->data_ref_info
 255 #define STMT_VINFO_MEMTAG(S)              (S)->memtag
 256 #define STMT_VINFO_PTR_INFO(S)            (S)->ptr_info
 257 #define STMT_VINFO_SUBVARS(S)             (S)->subvars
 258 #define STMT_VINFO_VECT_DR_BASE_ADDRESS(S)(S)->base_address
 259 #define STMT_VINFO_VECT_INIT_OFFSET(S)    (S)->initial_offset
 260 #define STMT_VINFO_VECT_STEP(S)           (S)->step
 261 #define STMT_VINFO_VECT_BASE_ALIGNED_P(S) (S)->base_aligned_p
 262 #define STMT_VINFO_VECT_MISALIGNMENT(S)   (S)->misalignment
 263 #define STMT_VINFO_SAME_ALIGN_REFS(S)     (S)->same_align_refs
 264 #define STMT_VINFO_DEF_TYPE(S)            (S)->def_type
 265
 266 static inline void set_stmt_info (tree_ann_t ann, stmt_vec_info stmt_info);
 267 static inline stmt_vec_info vinfo_for_stmt (tree stmt);
 268
 269 static inline void
 270 set_stmt_info (tree_ann_t ann, stmt_vec_info stmt_info)
 271 {
 272   if (ann)
 273     ann->common.aux = (char *) stmt_info;
 274 }
 275
 276 static inline stmt_vec_info
 277 vinfo_for_stmt (tree stmt)
 278 {
 279   tree_ann_t ann = tree_ann (stmt);
 280   return ann ? (stmt_vec_info) ann->common.aux : NULL;
 281 }
 282
 283 /*-----------------------------------------------------------------*/
 284 /* Info on data references alignment.                              */
 285 /*-----------------------------------------------------------------*/
 286
 287 /* Reflects actual alignment of first access in the vectorized loop,
 288    taking into account peeling/versioning if applied.  */
 289 #define DR_MISALIGNMENT(DR)   (DR)->aux
 290
 291 static inline bool
 292 aligned_access_p (struct data_reference *data_ref_info)
 293 {
 294   return (DR_MISALIGNMENT (data_ref_info) == 0);
 295 }
 296
 297 static inline bool
 298 known_alignment_for_access_p (struct data_reference *data_ref_info)
 299 {
 300   return (DR_MISALIGNMENT (data_ref_info) != -1);
 301 }
 302
 303 /* Perform signed modulo, always returning a non-negative value.  */
 304 #define VECT_SMODULO(x,y) ((x) % (y) < 0 ? ((x) % (y) + (y)) : (x) % (y))
 305
 306 /* vect_dump will be set to stderr or dump_file if exist.  */
 307 extern FILE *vect_dump;
 308 extern enum verbosity_levels vect_verbosity_level;
 309
 310 /* Number of loops, at the beginning of vectorization.  */
 311 extern unsigned int vect_loops_num;
 312 /*-----------------------------------------------------------------*/
 313 /* Function prototypes.                                            */
 314 /*-----------------------------------------------------------------*/
 315
 316 /*************************************************************************
 317   Simple Loop Peeling Utilities - in tree-vectorizer.c
 318  *************************************************************************/
 319 /* Entry point for peeling of simple loops.
 320    Peel the first/last iterations of a loop.
 321    It can be used outside of the vectorizer for loops that are simple enough
 322    (see function documentation).  In the vectorizer it is used to peel the
 323    last few iterations when the loop bound is unknown or does not evenly
 324    divide by the vectorization factor, and to peel the first few iterations
 325    to force the alignment of data references in the loop.  */
 326 extern struct loop *slpeel_tree_peel_loop_to_edge
 327   (struct loop *, struct loops *, edge, tree, tree, bool);
 328 extern void slpeel_make_loop_iterate_ntimes (struct loop *, tree);
 329 extern bool slpeel_can_duplicate_loop_p (struct loop *, edge);
 330 #ifdef ENABLE_CHECKING
 331 extern void slpeel_verify_cfg_after_peeling (struct loop *, struct loop *);
 332 #endif
 333
 334
 335 /*************************************************************************
 336   General Vectorization Utilities
 337  *************************************************************************/
 338 /** In tree-vectorizer.c **/
 339 extern tree vect_strip_conversion (tree);
 340 extern tree get_vectype_for_scalar_type (tree);
 341 extern bool vect_is_simple_use (tree, loop_vec_info, tree *, tree *,
 342                                 enum vect_def_type *);
 343 extern bool vect_is_simple_iv_evolution (unsigned, tree, tree *, tree *);
 344 extern tree vect_is_simple_reduction (struct loop *, tree);
 345 extern bool vect_can_force_dr_alignment_p (tree, unsigned int);
 346 extern enum dr_alignment_support vect_supportable_dr_alignment
 347   (struct data_reference *);
 348 /* Creation and deletion of loop and stmt info structs.  */
 349 extern loop_vec_info new_loop_vec_info (struct loop *loop);
 350 extern void destroy_loop_vec_info (loop_vec_info);
 351 extern stmt_vec_info new_stmt_vec_info (tree stmt, loop_vec_info);
 352 /* Main driver.  */
 353 extern void vectorize_loops (struct loops *);
 354
 355 /** In tree-vect-analyze.c  **/
 356 /* Driver for analysis stage.  */
 357 extern loop_vec_info vect_analyze_loop (struct loop *);
 358
 359 /** In tree-vect-transform.c  **/
 360 extern bool vectorizable_load (tree, block_stmt_iterator *, tree *);
 361 extern bool vectorizable_store (tree, block_stmt_iterator *, tree *);
 362 extern bool vectorizable_operation (tree, block_stmt_iterator *, tree *);
 363 extern bool vectorizable_assignment (tree, block_stmt_iterator *, tree *);
 364 extern bool vectorizable_condition (tree, block_stmt_iterator *, tree *);
 365 extern bool vectorizable_live_operation (tree, block_stmt_iterator *, tree *);
 366 /* Driver for transformation stage.  */
 367 extern void vect_transform_loop (loop_vec_info, struct loops *);
 368
 369 /*************************************************************************
 370   Vectorization Debug Information - in tree-vectorizer.c
 371  *************************************************************************/
 372 extern bool vect_print_dump_info (enum verbosity_levels, LOC);
 373 extern void vect_set_verbosity_level (const char *);
 374 extern LOC find_loop_location (struct loop *);
 375
 376 #endif  /* GCC_TREE_VECTORIZER_H  */