gcc/tree-data-ref.h

   1 /* Data references and dependences detectors.
   2    Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009
   3    Free Software Foundation, Inc.
   4    Contributed by Sebastian Pop <pop@cri.ensmp.fr>
   5
   6 This file is part of GCC.
   7
   8 GCC is free software; you can redistribute it and/or modify it under
   9 the terms of the GNU General Public License as published by the Free
  10 Software Foundation; either version 3, or (at your option) any later
  11 version.
  12
  13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  16 for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with GCC; see the file COPYING3.  If not see
  20 <http://www.gnu.org/licenses/>.  */
  21
  22 #ifndef GCC_TREE_DATA_REF_H
  23 #define GCC_TREE_DATA_REF_H
  24
  25 #include "graphds.h"
  26 #include "lambda.h"
  27 #include "omega.h"
  28 #include "tree-chrec.h"
  29
  30 /*
  31   innermost_loop_behavior describes the evolution of the address of the memory
  32   reference in the innermost enclosing loop.  The address is expressed as
  33   BASE + STEP * # of iteration, and base is further decomposed as the base
  34   pointer (BASE_ADDRESS),  loop invariant offset (OFFSET) and
  35   constant offset (INIT).  Examples, in loop nest
  36
  37   for (i = 0; i < 100; i++)
  38     for (j = 3; j < 100; j++)
  39
  40                        Example 1                      Example 2
  41       data-ref         a[j].b[i][j]                   *(p + x + 16B + 4B * j)
  42
  43
  44   innermost_loop_behavior
  45       base_address     &a                             p
  46       offset           i * D_i                        x
  47       init             3 * D_j + offsetof (b)         28
  48       step             D_j                            4
  49
  50   */
  51 struct innermost_loop_behavior
  52 {
  53   tree base_address;
  54   tree offset;
  55   tree init;
  56   tree step;
  57
  58   /* Alignment information.  ALIGNED_TO is set to the largest power of two
  59      that divides OFFSET.  */
  60   tree aligned_to;
  61 };
  62
  63 /* Describes the evolutions of indices of the memory reference.  The indices
  64    are indices of the ARRAY_REFs and the operands of INDIRECT_REFs.
  65    For ARRAY_REFs, BASE_OBJECT is the reference with zeroed indices
  66    (note that this reference does not have to be valid, if zero does not
  67    belong to the range of the array; hence it is not recommended to use
  68    BASE_OBJECT in any code generation).  For INDIRECT_REFs, the address is
  69    set to the loop-invariant part of the address of the object, except for
  70    the constant offset.  For the examples above,
  71
  72    base_object:        a[0].b[0][0]                   *(p + x + 4B * j_0)
  73    indices:            {j_0, +, 1}_2                  {16, +, 4}_2
  74                        {i_0, +, 1}_1
  75                        {j_0, +, 1}_2
  76 */
  77
  78 struct indices
  79 {
  80   /* The object.  */
  81   tree base_object;
  82
  83   /* A list of chrecs.  Access functions of the indices.  */
  84   VEC(tree,heap) *access_fns;
  85 };
  86
  87 struct dr_alias
  88 {
  89   /* The alias information that should be used for new pointers to this
  90      location.  SYMBOL_TAG is either a DECL or a SYMBOL_MEMORY_TAG.  */
  91   struct ptr_info_def *ptr_info;
  92
  93   /* The set of virtual operands corresponding to this memory reference,
  94      serving as a description of the alias information for the memory
  95      reference.  This could be eliminated if we had alias oracle.  */
  96   bitmap vops;
  97 };
  98
  99 typedef struct scop *scop_p;
 100
 101 /* Each vector of the access matrix represents a linear access
 102    function for a subscript.  First elements correspond to the
 103    leftmost indices, ie. for a[i][j] the first vector corresponds to
 104    the subscript in "i".  The elements of a vector are relative to
 105    the loop nests in which the data reference is considered,
 106    i.e. the vector is relative to the SCoP that provides the context
 107    in which this data reference occurs.
 108
 109    For example, in
 110
 111    | loop_1
 112    |    loop_2
 113    |      a[i+3][2*j+n-1]
 114
 115    if "i" varies in loop_1 and "j" varies in loop_2, the access
 116    matrix with respect to the loop nest {loop_1, loop_2} is:
 117
 118    | loop_1  loop_2  param_n  cst
 119    |   1       0        0      3
 120    |   0       2        1     -1
 121
 122    whereas the access matrix with respect to loop_2 considers "i" as
 123    a parameter:
 124
 125    | loop_2  param_i  param_n  cst
 126    |   0       1         0      3
 127    |   2       0         1     -1
 128 */
 129 struct access_matrix
 130 {
 131   VEC (loop_p, heap) *loop_nest;
 132   int nb_induction_vars;
 133   VEC (tree, heap) *parameters;
 134   VEC (lambda_vector, gc) *matrix;
 135 };
 136
 137 #define AM_LOOP_NEST(M) (M)->loop_nest
 138 #define AM_NB_INDUCTION_VARS(M) (M)->nb_induction_vars
 139 #define AM_PARAMETERS(M) (M)->parameters
 140 #define AM_MATRIX(M) (M)->matrix
 141 #define AM_NB_PARAMETERS(M) (VEC_length (tree, AM_PARAMETERS(M)))
 142 #define AM_CONST_COLUMN_INDEX(M) (AM_NB_INDUCTION_VARS (M) + AM_NB_PARAMETERS (M))
 143 #define AM_NB_COLUMNS(M) (AM_NB_INDUCTION_VARS (M) + AM_NB_PARAMETERS (M) + 1)
 144 #define AM_GET_SUBSCRIPT_ACCESS_VECTOR(M, I) VEC_index (lambda_vector, AM_MATRIX (M), I)
 145 #define AM_GET_ACCESS_MATRIX_ELEMENT(M, I, J) AM_GET_SUBSCRIPT_ACCESS_VECTOR (M, I)[J]
 146
 147 /* Return the column in the access matrix of LOOP_NUM.  */
 148
 149 static inline int
 150 am_vector_index_for_loop (struct access_matrix *access_matrix, int loop_num)
 151 {
 152   int i;
 153   loop_p l;
 154
 155   for (i = 0; VEC_iterate (loop_p, AM_LOOP_NEST (access_matrix), i, l); i++)
 156     if (l->num == loop_num)
 157       return i;
 158
 159   gcc_unreachable();
 160 }
 161
 162 int access_matrix_get_index_for_parameter (tree, struct access_matrix *);
 163
 164 struct data_reference
 165 {
 166   /* A pointer to the statement that contains this DR.  */
 167   gimple stmt;
 168
 169   /* A pointer to the memory reference.  */
 170   tree ref;
 171
 172   /* Auxiliary info specific to a pass.  */
 173   void *aux;
 174
 175   /* True when the data reference is in RHS of a stmt.  */
 176   bool is_read;
 177
 178   /* Behavior of the memory reference in the innermost loop.  */
 179   struct innermost_loop_behavior innermost;
 180
 181   /* Subscripts of this data reference.  */
 182   struct indices indices;
 183
 184   /* Alias information for the data reference.  */
 185   struct dr_alias alias;
 186
 187   /* The SCoP in which the data reference was analyzed.  */
 188   scop_p scop;
 189
 190   /* Matrix representation for the data access functions.  */
 191   struct access_matrix *access_matrix;
 192 };
 193
 194 #define DR_SCOP(DR)                (DR)->scop
 195 #define DR_STMT(DR)                (DR)->stmt
 196 #define DR_REF(DR)                 (DR)->ref
 197 #define DR_BASE_OBJECT(DR)         (DR)->indices.base_object
 198 #define DR_ACCESS_FNS(DR)          (DR)->indices.access_fns
 199 #define DR_ACCESS_FN(DR, I)        VEC_index (tree, DR_ACCESS_FNS (DR), I)
 200 #define DR_NUM_DIMENSIONS(DR)      VEC_length (tree, DR_ACCESS_FNS (DR))
 201 #define DR_IS_READ(DR)             (DR)->is_read
 202 #define DR_BASE_ADDRESS(DR)        (DR)->innermost.base_address
 203 #define DR_OFFSET(DR)              (DR)->innermost.offset
 204 #define DR_INIT(DR)                (DR)->innermost.init
 205 #define DR_STEP(DR)                (DR)->innermost.step
 206 #define DR_PTR_INFO(DR)            (DR)->alias.ptr_info
 207 #define DR_ALIGNED_TO(DR)          (DR)->innermost.aligned_to
 208 #define DR_ACCESS_MATRIX(DR)       (DR)->access_matrix
 209
 210 typedef struct data_reference *data_reference_p;
 211 DEF_VEC_P(data_reference_p);
 212 DEF_VEC_ALLOC_P (data_reference_p, heap);
 213
 214 enum data_dependence_direction {
 215   dir_positive,
 216   dir_negative,
 217   dir_equal,
 218   dir_positive_or_negative,
 219   dir_positive_or_equal,
 220   dir_negative_or_equal,
 221   dir_star,
 222   dir_independent
 223 };
 224
 225 /* The description of the grid of iterations that overlap.  At most
 226    two loops are considered at the same time just now, hence at most
 227    two functions are needed.  For each of the functions, we store
 228    the vector of coefficients, f[0] + x * f[1] + y * f[2] + ...,
 229    where x, y, ... are variables.  */
 230
 231 #define MAX_DIM 2
 232
 233 /* Special values of N.  */
 234 #define NO_DEPENDENCE 0
 235 #define NOT_KNOWN (MAX_DIM + 1)
 236 #define CF_NONTRIVIAL_P(CF) ((CF)->n != NO_DEPENDENCE && (CF)->n != NOT_KNOWN)
 237 #define CF_NOT_KNOWN_P(CF) ((CF)->n == NOT_KNOWN)
 238 #define CF_NO_DEPENDENCE_P(CF) ((CF)->n == NO_DEPENDENCE)
 239
 240 typedef VEC (tree, heap) *affine_fn;
 241
 242 typedef struct
 243 {
 244   unsigned n;
 245   affine_fn fns[MAX_DIM];
 246 } conflict_function;
 247
 248 /* What is a subscript?  Given two array accesses a subscript is the
 249    tuple composed of the access functions for a given dimension.
 250    Example: Given A[f1][f2][f3] and B[g1][g2][g3], there are three
 251    subscripts: (f1, g1), (f2, g2), (f3, g3).  These three subscripts
 252    are stored in the data_dependence_relation structure under the form
 253    of an array of subscripts.  */
 254
 255 struct subscript
 256 {
 257   /* A description of the iterations for which the elements are
 258      accessed twice.  */
 259   conflict_function *conflicting_iterations_in_a;
 260   conflict_function *conflicting_iterations_in_b;
 261
 262   /* This field stores the information about the iteration domain
 263      validity of the dependence relation.  */
 264   tree last_conflict;
 265
 266   /* Distance from the iteration that access a conflicting element in
 267      A to the iteration that access this same conflicting element in
 268      B.  The distance is a tree scalar expression, i.e. a constant or a
 269      symbolic expression, but certainly not a chrec function.  */
 270   tree distance;
 271 };
 272
 273 typedef struct subscript *subscript_p;
 274 DEF_VEC_P(subscript_p);
 275 DEF_VEC_ALLOC_P (subscript_p, heap);
 276
 277 #define SUB_CONFLICTS_IN_A(SUB) SUB->conflicting_iterations_in_a
 278 #define SUB_CONFLICTS_IN_B(SUB) SUB->conflicting_iterations_in_b
 279 #define SUB_LAST_CONFLICT(SUB) SUB->last_conflict
 280 #define SUB_DISTANCE(SUB) SUB->distance
 281
 282 /* A data_dependence_relation represents a relation between two
 283    data_references A and B.  */
 284
 285 struct data_dependence_relation
 286 {
 287
 288   struct data_reference *a;
 289   struct data_reference *b;
 290
 291   /* A "yes/no/maybe" field for the dependence relation:
 292
 293      - when "ARE_DEPENDENT == NULL_TREE", there exist a dependence
 294        relation between A and B, and the description of this relation
 295        is given in the SUBSCRIPTS array,
 296
 297      - when "ARE_DEPENDENT == chrec_known", there is no dependence and
 298        SUBSCRIPTS is empty,
 299
 300      - when "ARE_DEPENDENT == chrec_dont_know", there may be a dependence,
 301        but the analyzer cannot be more specific.  */
 302   tree are_dependent;
 303
 304   /* For each subscript in the dependence test, there is an element in
 305      this array.  This is the attribute that labels the edge A->B of
 306      the data_dependence_relation.  */
 307   VEC (subscript_p, heap) *subscripts;
 308
 309   /* The analyzed loop nest.  */
 310   VEC (loop_p, heap) *loop_nest;
 311
 312   /* The classic direction vector.  */
 313   VEC (lambda_vector, heap) *dir_vects;
 314
 315   /* The classic distance vector.  */
 316   VEC (lambda_vector, heap) *dist_vects;
 317
 318   /* An index in loop_nest for the innermost loop that varies for
 319      this data dependence relation.  */
 320   unsigned inner_loop;
 321
 322   /* Is the dependence reversed with respect to the lexicographic order?  */
 323   bool reversed_p;
 324
 325   /* When the dependence relation is affine, it can be represented by
 326      a distance vector.  */
 327   bool affine_p;
 328
 329   /* Set to true when the dependence relation is on the same data
 330      access.  */
 331   bool self_reference_p;
 332 };
 333
 334 typedef struct data_dependence_relation *ddr_p;
 335 DEF_VEC_P(ddr_p);
 336 DEF_VEC_ALLOC_P(ddr_p,heap);
 337
 338 #define DDR_A(DDR) DDR->a
 339 #define DDR_B(DDR) DDR->b
 340 #define DDR_AFFINE_P(DDR) DDR->affine_p
 341 #define DDR_ARE_DEPENDENT(DDR) DDR->are_dependent
 342 #define DDR_SUBSCRIPTS(DDR) DDR->subscripts
 343 #define DDR_SUBSCRIPT(DDR, I) VEC_index (subscript_p, DDR_SUBSCRIPTS (DDR), I)
 344 #define DDR_NUM_SUBSCRIPTS(DDR) VEC_length (subscript_p, DDR_SUBSCRIPTS (DDR))
 345
 346 #define DDR_LOOP_NEST(DDR) DDR->loop_nest
 347 /* The size of the direction/distance vectors: the number of loops in
 348    the loop nest.  */
 349 #define DDR_NB_LOOPS(DDR) (VEC_length (loop_p, DDR_LOOP_NEST (DDR)))
 350 #define DDR_INNER_LOOP(DDR) DDR->inner_loop
 351 #define DDR_SELF_REFERENCE(DDR) DDR->self_reference_p
 352
 353 #define DDR_DIST_VECTS(DDR) ((DDR)->dist_vects)
 354 #define DDR_DIR_VECTS(DDR) ((DDR)->dir_vects)
 355 #define DDR_NUM_DIST_VECTS(DDR) \
 356   (VEC_length (lambda_vector, DDR_DIST_VECTS (DDR)))
 357 #define DDR_NUM_DIR_VECTS(DDR) \
 358   (VEC_length (lambda_vector, DDR_DIR_VECTS (DDR)))
 359 #define DDR_DIR_VECT(DDR, I) \
 360   VEC_index (lambda_vector, DDR_DIR_VECTS (DDR), I)
 361 #define DDR_DIST_VECT(DDR, I) \
 362   VEC_index (lambda_vector, DDR_DIST_VECTS (DDR), I)
 363 #define DDR_REVERSED_P(DDR) DDR->reversed_p
 364
 365 \f
 366
 367 /* Describes a location of a memory reference.  */
 368
 369 typedef struct data_ref_loc_d
 370 {
 371   /* Position of the memory reference.  */
 372   tree *pos;
 373
 374   /* True if the memory reference is read.  */
 375   bool is_read;
 376 } data_ref_loc;
 377
 378 DEF_VEC_O (data_ref_loc);
 379 DEF_VEC_ALLOC_O (data_ref_loc, heap);
 380
 381 bool get_references_in_stmt (gimple, VEC (data_ref_loc, heap) **);
 382 bool dr_analyze_innermost (struct data_reference *);
 383 extern bool compute_data_dependences_for_loop (struct loop *, bool,
 384                                                VEC (data_reference_p, heap) **,
 385                                                VEC (ddr_p, heap) **);
 386 extern bool compute_data_dependences_for_bb (basic_block, bool,
 387                                              VEC (data_reference_p, heap) **,
 388                                              VEC (ddr_p, heap) **);
 389 extern tree find_data_references_in_loop (struct loop *,
 390                                           VEC (data_reference_p, heap) **);
 391 extern void print_direction_vector (FILE *, lambda_vector, int);
 392 extern void print_dir_vectors (FILE *, VEC (lambda_vector, heap) *, int);
 393 extern void print_dist_vectors (FILE *, VEC (lambda_vector, heap) *, int);
 394 extern void dump_subscript (FILE *, struct subscript *);
 395 extern void dump_ddrs (FILE *, VEC (ddr_p, heap) *);
 396 extern void dump_dist_dir_vectors (FILE *, VEC (ddr_p, heap) *);
 397 extern void dump_data_reference (FILE *, struct data_reference *);
 398 extern void dump_data_references (FILE *, VEC (data_reference_p, heap) *);
 399 extern void debug_data_dependence_relation (struct data_dependence_relation *);
 400 extern void dump_data_dependence_relation (FILE *,
 401                                            struct data_dependence_relation *);
 402 extern void dump_data_dependence_relations (FILE *, VEC (ddr_p, heap) *);
 403 extern void debug_data_dependence_relations (VEC (ddr_p, heap) *);
 404 extern void dump_data_dependence_direction (FILE *,
 405                                             enum data_dependence_direction);
 406 extern void free_dependence_relation (struct data_dependence_relation *);
 407 extern void free_dependence_relations (VEC (ddr_p, heap) *);
 408 extern void free_data_ref (data_reference_p);
 409 extern void free_data_refs (VEC (data_reference_p, heap) *);
 410 extern bool find_data_references_in_stmt (struct loop *, gimple,
 411                                           VEC (data_reference_p, heap) **);
 412 struct data_reference *create_data_ref (struct loop *, tree, gimple, bool);
 413 extern bool find_loop_nest (struct loop *, VEC (loop_p, heap) **);
 414 extern void compute_all_dependences (VEC (data_reference_p, heap) *,
 415                                      VEC (ddr_p, heap) **, VEC (loop_p, heap) *,
 416                                      bool);
 417
 418 extern void create_rdg_vertices (struct graph *, VEC (gimple, heap) *);
 419 extern bool dr_may_alias_p (const struct data_reference *,
 420                             const struct data_reference *);
 421 extern bool stmt_simple_memref_p (struct loop *, gimple, tree);
 422
 423 /* Return true when the DDR contains two data references that have the
 424    same access functions.  */
 425
 426 static inline bool
 427 same_access_functions (const struct data_dependence_relation *ddr)
 428 {
 429   unsigned i;
 430
 431   for (i = 0; i < DDR_NUM_SUBSCRIPTS (ddr); i++)
 432     if (!eq_evolutions_p (DR_ACCESS_FN (DDR_A (ddr), i),
 433                           DR_ACCESS_FN (DDR_B (ddr), i)))
 434       return false;
 435
 436   return true;
 437 }
 438
 439 /* Return true when DDR is an anti-dependence relation.  */
 440
 441 static inline bool
 442 ddr_is_anti_dependent (ddr_p ddr)
 443 {
 444   return (DDR_ARE_DEPENDENT (ddr) == NULL_TREE
 445           && DR_IS_READ (DDR_A (ddr))
 446           && !DR_IS_READ (DDR_B (ddr))
 447           && !same_access_functions (ddr));
 448 }
 449
 450 /* Return true when DEPENDENCE_RELATIONS contains an anti-dependence.  */
 451
 452 static inline bool
 453 ddrs_have_anti_deps (VEC (ddr_p, heap) *dependence_relations)
 454 {
 455   unsigned i;
 456   ddr_p ddr;
 457
 458   for (i = 0; VEC_iterate (ddr_p, dependence_relations, i, ddr); i++)
 459     if (ddr_is_anti_dependent (ddr))
 460       return true;
 461
 462   return false;
 463 }
 464
 465 /* Return the dependence level for the DDR relation.  */
 466
 467 static inline unsigned
 468 ddr_dependence_level (ddr_p ddr)
 469 {
 470   unsigned vector;
 471   unsigned level = 0;
 472
 473   if (DDR_DIST_VECTS (ddr))
 474     level = dependence_level (DDR_DIST_VECT (ddr, 0), DDR_NB_LOOPS (ddr));
 475
 476   for (vector = 1; vector < DDR_NUM_DIST_VECTS (ddr); vector++)
 477     level = MIN (level, dependence_level (DDR_DIST_VECT (ddr, vector),
 478                                           DDR_NB_LOOPS (ddr)));
 479   return level;
 480 }
 481
 482 \f
 483
 484 /* A Reduced Dependence Graph (RDG) vertex representing a statement.  */
 485 typedef struct rdg_vertex
 486 {
 487   /* The statement represented by this vertex.  */
 488   gimple stmt;
 489
 490   /* True when the statement contains a write to memory.  */
 491   bool has_mem_write;
 492
 493   /* True when the statement contains a read from memory.  */
 494   bool has_mem_reads;
 495 } *rdg_vertex_p;
 496
 497 #define RDGV_STMT(V)     ((struct rdg_vertex *) ((V)->data))->stmt
 498 #define RDGV_HAS_MEM_WRITE(V) ((struct rdg_vertex *) ((V)->data))->has_mem_write
 499 #define RDGV_HAS_MEM_READS(V) ((struct rdg_vertex *) ((V)->data))->has_mem_reads
 500 #define RDG_STMT(RDG, I) RDGV_STMT (&(RDG->vertices[I]))
 501 #define RDG_MEM_WRITE_STMT(RDG, I) RDGV_HAS_MEM_WRITE (&(RDG->vertices[I]))
 502 #define RDG_MEM_READS_STMT(RDG, I) RDGV_HAS_MEM_READS (&(RDG->vertices[I]))
 503
 504 void dump_rdg_vertex (FILE *, struct graph *, int);
 505 void debug_rdg_vertex (struct graph *, int);
 506 void dump_rdg_component (FILE *, struct graph *, int, bitmap);
 507 void debug_rdg_component (struct graph *, int);
 508 void dump_rdg (FILE *, struct graph *);
 509 void debug_rdg (struct graph *);
 510 void dot_rdg (struct graph *);
 511 int rdg_vertex_for_stmt (struct graph *, gimple);
 512
 513 /* Data dependence type.  */
 514
 515 enum rdg_dep_type
 516 {
 517   /* Read After Write (RAW).  */
 518   flow_dd = 'f',
 519
 520   /* Write After Read (WAR).  */
 521   anti_dd = 'a',
 522
 523   /* Write After Write (WAW).  */
 524   output_dd = 'o',
 525
 526   /* Read After Read (RAR).  */
 527   input_dd = 'i'
 528 };
 529
 530 /* Dependence information attached to an edge of the RDG.  */
 531
 532 typedef struct rdg_edge
 533 {
 534   /* Type of the dependence.  */
 535   enum rdg_dep_type type;
 536
 537   /* Levels of the dependence: the depth of the loops that carry the
 538      dependence.  */
 539   unsigned level;
 540
 541   /* Dependence relation between data dependences, NULL when one of
 542      the vertices is a scalar.  */
 543   ddr_p relation;
 544 } *rdg_edge_p;
 545
 546 #define RDGE_TYPE(E)        ((struct rdg_edge *) ((E)->data))->type
 547 #define RDGE_LEVEL(E)       ((struct rdg_edge *) ((E)->data))->level
 548 #define RDGE_RELATION(E)    ((struct rdg_edge *) ((E)->data))->relation
 549
 550 struct graph *build_rdg (struct loop *);
 551 struct graph *build_empty_rdg (int);
 552 void free_rdg (struct graph *);
 553
 554 /* Return the index of the variable VAR in the LOOP_NEST array.  */
 555
 556 static inline int
 557 index_in_loop_nest (int var, VEC (loop_p, heap) *loop_nest)
 558 {
 559   struct loop *loopi;
 560   int var_index;
 561
 562   for (var_index = 0; VEC_iterate (loop_p, loop_nest, var_index, loopi);
 563        var_index++)
 564     if (loopi->num == var)
 565       break;
 566
 567   return var_index;
 568 }
 569
 570 void stores_from_loop (struct loop *, VEC (gimple, heap) **);
 571 void remove_similar_memory_refs (VEC (gimple, heap) **);
 572 bool rdg_defs_used_in_other_loops_p (struct graph *, int);
 573 bool have_similar_memory_accesses (gimple, gimple);
 574
 575 /* Determines whether RDG vertices V1 and V2 access to similar memory
 576    locations, in which case they have to be in the same partition.  */
 577
 578 static inline bool
 579 rdg_has_similar_memory_accesses (struct graph *rdg, int v1, int v2)
 580 {
 581   return have_similar_memory_accesses (RDG_STMT (rdg, v1),
 582                                        RDG_STMT (rdg, v2));
 583 }
 584
 585 /* In lambda-code.c  */
 586 bool lambda_transform_legal_p (lambda_trans_matrix, int,
 587                                VEC (ddr_p, heap) *);
 588 void lambda_collect_parameters (VEC (data_reference_p, heap) *,
 589                                 VEC (tree, heap) **);
 590 bool lambda_compute_access_matrices (VEC (data_reference_p, heap) *,
 591                                      VEC (tree, heap) *, VEC (loop_p, heap) *);
 592
 593 /* In tree-data-ref.c  */
 594 void split_constant_offset (tree , tree *, tree *);
 595
 596 /* Strongly connected components of the reduced data dependence graph.  */
 597
 598 typedef struct rdg_component
 599 {
 600   int num;
 601   VEC (int, heap) *vertices;
 602 } *rdgc;
 603
 604 DEF_VEC_P (rdgc);
 605 DEF_VEC_ALLOC_P (rdgc, heap);
 606
 607 DEF_VEC_P (bitmap);
 608 DEF_VEC_ALLOC_P (bitmap, heap);
 609
 610 #endif  /* GCC_TREE_DATA_REF_H  */