gcc/ipa-prop.h

   1 /* Interprocedural analyses.
   2    Copyright (C) 2005-2013 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef IPA_PROP_H
  21 #define IPA_PROP_H
  22
  23 #include "tree.h"
  24 #include "vec.h"
  25 #include "cgraph.h"
  26 #include "gimple.h"
  27 #include "alloc-pool.h"
  28
  29 /* The following definitions and interfaces are used by
  30    interprocedural analyses or parameters.  */
  31
  32 #define IPA_UNDESCRIBED_USE -1
  33
  34 /* ipa-prop.c stuff (ipa-cp, indirect inlining):  */
  35
  36 /* A jump function for a callsite represents the values passed as actual
  37    arguments of the callsite.  They were originally proposed in a paper called
  38    "Interprocedural Constant Propagation", by David Callahan, Keith D Cooper,
  39    Ken Kennedy, Linda Torczon in Comp86, pg 152-161.  There are three main
  40    types of values :
  41
  42    Pass-through - the caller's formal parameter is passed as an actual
  43                   argument, possibly one simple operation performed on it.
  44    Constant     - a constant (is_gimple_ip_invariant)is passed as an actual
  45                   argument.
  46    Unknown      - neither of the above.
  47
  48    IPA_JF_ANCESTOR is a special pass-through jump function, which means that
  49    the result is an address of a part of the object pointed to by the formal
  50    parameter to which the function refers.  It is mainly intended to represent
  51    getting addresses of of ancestor fields in C++
  52    (e.g. &this_1(D)->D.1766.D.1756).  Note that if the original pointer is
  53    NULL, ancestor jump function must behave like a simple pass-through.
  54
  55    Other pass-through functions can either simply pass on an unchanged formal
  56    parameter or can apply one simple binary operation to it (such jump
  57    functions are called polynomial).
  58
  59    IPA_JF_KNOWN_TYPE is a special type of an "unknown" function that applies
  60    only to pointer parameters.  It means that even though we cannot prove that
  61    the passed value is an interprocedural constant, we still know the exact
  62    type of the containing object which may be valuable for devirtualization.
  63
  64    Jump functions are computed in ipa-prop.c by function
  65    update_call_notes_after_inlining.  Some information can be lost and jump
  66    functions degraded accordingly when inlining, see
  67    update_call_notes_after_inlining in the same file.  */
  68
  69 enum jump_func_type
  70 {
  71   IPA_JF_UNKNOWN = 0,  /* newly allocated and zeroed jump functions default */
  72   IPA_JF_KNOWN_TYPE,        /* represented by field known_type */
  73   IPA_JF_CONST,             /* represented by field costant */
  74   IPA_JF_PASS_THROUGH,      /* represented by field pass_through */
  75   IPA_JF_ANCESTOR           /* represented by field ancestor */
  76 };
  77
  78 /* Structure holding data required to describe a known type jump function.  */
  79 struct GTY(()) ipa_known_type_data
  80 {
  81   /* Offset of the component of the base_type being described.  */
  82   HOST_WIDE_INT offset;
  83   /* Type of the whole object.  */
  84   tree base_type;
  85   /* Type of the component of the object that is being described.  */
  86   tree component_type;
  87 };
  88
  89 struct ipa_cst_ref_desc;
  90
  91 /* Structure holding data required to describe a constant jump function.  */
  92 struct GTY(()) ipa_constant_data
  93 {
  94   /* THe value of the constant.  */
  95   tree value;
  96   /* Pointer to the structure that describes the reference.  */
  97   struct ipa_cst_ref_desc GTY((skip)) *rdesc;
  98 };
  99
 100 /* Structure holding data required to describe a pass-through jump function.  */
 101
 102 struct GTY(()) ipa_pass_through_data
 103 {
 104   /* If an operation is to be performed on the original parameter, this is the
 105      second (constant) operand.  */
 106   tree operand;
 107   /* Number of the caller's formal parameter being passed.  */
 108   int formal_id;
 109   /* Operation that is performed on the argument before it is passed on.
 110      NOP_EXPR means no operation.  Otherwise oper must be a simple binary
 111      arithmetic operation where the caller's parameter is the first operand and
 112      operand field from this structure is the second one.  */
 113   enum tree_code operation;
 114   /* When the passed value is a pointer, it is set to true only when we are
 115      certain that no write to the object it points to has occurred since the
 116      caller functions started execution, except for changes noted in the
 117      aggregate part of the jump function (see description of
 118      ipa_agg_jump_function).  The flag is used only when the operation is
 119      NOP_EXPR.  */
 120   bool agg_preserved;
 121 };
 122
 123 /* Structure holding data required to describe an ancestor pass-through
 124    jump function.  */
 125
 126 struct GTY(()) ipa_ancestor_jf_data
 127 {
 128   /* Offset of the field representing the ancestor.  */
 129   HOST_WIDE_INT offset;
 130   /* Type of the result.  */
 131   tree type;
 132   /* Number of the caller's formal parameter being passed.  */
 133   int formal_id;
 134   /* Flag with the same meaning like agg_preserve in ipa_pass_through_data.  */
 135   bool agg_preserved;
 136 };
 137
 138 /* An element in an aggegate part of a jump function describing a known value
 139    at a given offset.  When it is part of a pass-through jump function with
 140    agg_preserved set or an ancestor jump function with agg_preserved set, all
 141    unlisted positions are assumed to be preserved but the value can be a type
 142    node, which means that the particular piece (starting at offset and having
 143    the size of the type) is clobbered with an unknown value.  When
 144    agg_preserved is false or the type of the containing jump function is
 145    different, all unlisted parts are assumed to be unknown and all values must
 146    fulfill is_gimple_ip_invariant.  */
 147
 148 typedef struct GTY(()) ipa_agg_jf_item
 149 {
 150   /* The offset at which the known value is located within the aggregate.  */
 151   HOST_WIDE_INT offset;
 152
 153   /* The known constant or type if this is a clobber.  */
 154   tree value;
 155 } ipa_agg_jf_item_t;
 156
 157
 158 /* Aggregate jump function - i.e. description of contents of aggregates passed
 159    either by reference or value.  */
 160
 161 struct GTY(()) ipa_agg_jump_function
 162 {
 163   /* Description of the individual items.  */
 164   vec<ipa_agg_jf_item_t, va_gc> *items;
 165   /* True if the data was passed by reference (as opposed to by value). */
 166   bool by_ref;
 167 };
 168
 169 typedef struct ipa_agg_jump_function *ipa_agg_jump_function_p;
 170 typedef struct ipa_agg_jump_function ipa_agg_jump_function_t;
 171
 172 /* A jump function for a callsite represents the values passed as actual
 173    arguments of the callsite. See enum jump_func_type for the various
 174    types of jump functions supported.  */
 175 typedef struct GTY (()) ipa_jump_func
 176 {
 177   /* Aggregate contants description.  See struct ipa_agg_jump_function and its
 178      description.  */
 179   struct ipa_agg_jump_function agg;
 180
 181   enum jump_func_type type;
 182   /* Represents a value of a jump function.  pass_through is used only in jump
 183      function context.  constant represents the actual constant in constant jump
 184      functions and member_cst holds constant c++ member functions.  */
 185   union jump_func_value
 186   {
 187     struct ipa_known_type_data GTY ((tag ("IPA_JF_KNOWN_TYPE"))) known_type;
 188     struct ipa_constant_data GTY ((tag ("IPA_JF_CONST"))) constant;
 189     struct ipa_pass_through_data GTY ((tag ("IPA_JF_PASS_THROUGH"))) pass_through;
 190     struct ipa_ancestor_jf_data GTY ((tag ("IPA_JF_ANCESTOR"))) ancestor;
 191   } GTY ((desc ("%1.type"))) value;
 192 } ipa_jump_func_t;
 193
 194
 195 /* Return the offset of the component that is described by a known type jump
 196    function JFUNC.  */
 197
 198 static inline HOST_WIDE_INT
 199 ipa_get_jf_known_type_offset (struct ipa_jump_func *jfunc)
 200 {
 201   gcc_checking_assert (jfunc->type == IPA_JF_KNOWN_TYPE);
 202   return jfunc->value.known_type.offset;
 203 }
 204
 205 /* Return the base type of a known type jump function JFUNC.  */
 206
 207 static inline tree
 208 ipa_get_jf_known_type_base_type (struct ipa_jump_func *jfunc)
 209 {
 210   gcc_checking_assert (jfunc->type == IPA_JF_KNOWN_TYPE);
 211   return jfunc->value.known_type.base_type;
 212 }
 213
 214 /* Return the component type of a known type jump function JFUNC.  */
 215
 216 static inline tree
 217 ipa_get_jf_known_type_component_type (struct ipa_jump_func *jfunc)
 218 {
 219   gcc_checking_assert (jfunc->type == IPA_JF_KNOWN_TYPE);
 220   return jfunc->value.known_type.component_type;
 221 }
 222
 223 /* Return the constant stored in a constant jump functin JFUNC.  */
 224
 225 static inline tree
 226 ipa_get_jf_constant (struct ipa_jump_func *jfunc)
 227 {
 228   gcc_checking_assert (jfunc->type == IPA_JF_CONST);
 229   return jfunc->value.constant.value;
 230 }
 231
 232 static inline struct ipa_cst_ref_desc *
 233 ipa_get_jf_constant_rdesc (struct ipa_jump_func *jfunc)
 234 {
 235   gcc_checking_assert (jfunc->type == IPA_JF_CONST);
 236   return jfunc->value.constant.rdesc;
 237 }
 238
 239 /* Return the operand of a pass through jmp function JFUNC.  */
 240
 241 static inline tree
 242 ipa_get_jf_pass_through_operand (struct ipa_jump_func *jfunc)
 243 {
 244   gcc_checking_assert (jfunc->type == IPA_JF_PASS_THROUGH);
 245   return jfunc->value.pass_through.operand;
 246 }
 247
 248 /* Return the number of the caller's formal parameter that a pass through jump
 249    function JFUNC refers to.  */
 250
 251 static inline int
 252 ipa_get_jf_pass_through_formal_id (struct ipa_jump_func *jfunc)
 253 {
 254   gcc_checking_assert (jfunc->type == IPA_JF_PASS_THROUGH);
 255   return jfunc->value.pass_through.formal_id;
 256 }
 257
 258 /* Return operation of a pass through jump function JFUNC.  */
 259
 260 static inline enum tree_code
 261 ipa_get_jf_pass_through_operation (struct ipa_jump_func *jfunc)
 262 {
 263   gcc_checking_assert (jfunc->type == IPA_JF_PASS_THROUGH);
 264   return jfunc->value.pass_through.operation;
 265 }
 266
 267 /* Return the agg_preserved flag of a pass through jump functin JFUNC.  */
 268
 269 static inline bool
 270 ipa_get_jf_pass_through_agg_preserved (struct ipa_jump_func *jfunc)
 271 {
 272   gcc_checking_assert (jfunc->type == IPA_JF_PASS_THROUGH);
 273   return jfunc->value.pass_through.agg_preserved;
 274 }
 275
 276 /* Return the offset of an ancestor jump function JFUNC.  */
 277
 278 static inline HOST_WIDE_INT
 279 ipa_get_jf_ancestor_offset (struct ipa_jump_func *jfunc)
 280 {
 281   gcc_checking_assert (jfunc->type == IPA_JF_ANCESTOR);
 282   return jfunc->value.ancestor.offset;
 283 }
 284
 285 /* Return the result type of an ancestor jump function JFUNC.  */
 286
 287 static inline tree
 288 ipa_get_jf_ancestor_type (struct ipa_jump_func *jfunc)
 289 {
 290   gcc_checking_assert (jfunc->type == IPA_JF_ANCESTOR);
 291   return jfunc->value.ancestor.type;
 292 }
 293
 294 /* Return the number of the caller's formal parameter that an ancestor jump
 295    function JFUNC refers to.  */
 296
 297 static inline int
 298 ipa_get_jf_ancestor_formal_id (struct ipa_jump_func *jfunc)
 299 {
 300   gcc_checking_assert (jfunc->type == IPA_JF_ANCESTOR);
 301   return jfunc->value.ancestor.formal_id;
 302 }
 303
 304 /* Return the agg_preserved flag of an ancestor jump functin JFUNC.  */
 305
 306 static inline bool
 307 ipa_get_jf_ancestor_agg_preserved (struct ipa_jump_func *jfunc)
 308 {
 309   gcc_checking_assert (jfunc->type == IPA_JF_ANCESTOR);
 310   return jfunc->value.ancestor.agg_preserved;
 311 }
 312
 313 /* Summary describing a single formal parameter.  */
 314
 315 struct ipa_param_descriptor
 316 {
 317   /* PARAM_DECL of this parameter.  */
 318   tree decl;
 319   /* If all uses of the parameter are described by ipa-prop structures, this
 320      says how many there are.  If any use could not be described by means of
 321      ipa-prop structures, this is IPA_UNDESCRIBED_USE.  */
 322   int controlled_uses;
 323   /* The parameter is used.  */
 324   unsigned used : 1;
 325 };
 326
 327 typedef struct ipa_param_descriptor ipa_param_descriptor_t;
 328 struct ipcp_lattice;
 329
 330 /* ipa_node_params stores information related to formal parameters of functions
 331    and some other information for interprocedural passes that operate on
 332    parameters (such as ipa-cp).  */
 333
 334 struct ipa_node_params
 335 {
 336   /* Information about individual formal parameters that are gathered when
 337      summaries are generated. */
 338   vec<ipa_param_descriptor_t> descriptors;
 339   /* Pointer to an array of structures describing individual formal
 340      parameters.  */
 341   struct ipcp_param_lattices *lattices;
 342   /* Only for versioned nodes this field would not be NULL,
 343      it points to the node that IPA cp cloned from.  */
 344   struct cgraph_node *ipcp_orig_node;
 345   /* If this node is an ipa-cp clone, these are the known values that describe
 346      what it has been specialized for.  */
 347   vec<tree> known_vals;
 348   /* Whether the param uses analysis has already been performed.  */
 349   unsigned uses_analysis_done : 1;
 350   /* Whether the function is enqueued in ipa-cp propagation stack.  */
 351   unsigned node_enqueued : 1;
 352   /* Whether we should create a specialized version based on values that are
 353      known to be constant in all contexts.  */
 354   unsigned do_clone_for_all_contexts : 1;
 355   /* Set if this is an IPA-CP clone for all contexts.  */
 356   unsigned is_all_contexts_clone : 1;
 357   /* Node has been completely replaced by clones and will be removed after
 358      ipa-cp is finished.  */
 359   unsigned node_dead : 1;
 360 };
 361
 362 /* ipa_node_params access functions.  Please use these to access fields that
 363    are or will be shared among various passes.  */
 364
 365 /* Return the number of formal parameters. */
 366
 367 static inline int
 368 ipa_get_param_count (struct ipa_node_params *info)
 369 {
 370   return info->descriptors.length ();
 371 }
 372
 373 /* Return the declaration of Ith formal parameter of the function corresponding
 374    to INFO.  Note there is no setter function as this array is built just once
 375    using ipa_initialize_node_params. */
 376
 377 static inline tree
 378 ipa_get_param (struct ipa_node_params *info, int i)
 379 {
 380   return info->descriptors[i].decl;
 381 }
 382
 383 /* Set the used flag corresponding to the Ith formal parameter of the function
 384    associated with INFO to VAL.  */
 385
 386 static inline void
 387 ipa_set_param_used (struct ipa_node_params *info, int i, bool val)
 388 {
 389   info->descriptors[i].used = val;
 390 }
 391
 392 /* Return how many uses described by ipa-prop a parameter has or
 393    IPA_UNDESCRIBED_USE if there is a use that is not described by these
 394    structures.  */
 395 static inline int
 396 ipa_get_controlled_uses (struct ipa_node_params *info, int i)
 397 {
 398   return info->descriptors[i].controlled_uses;
 399 }
 400
 401 /* Set the controlled counter of a given parameter.  */
 402
 403 static inline void
 404 ipa_set_controlled_uses (struct ipa_node_params *info, int i, int val)
 405 {
 406   info->descriptors[i].controlled_uses = val;
 407 }
 408
 409 /* Return the used flag corresponding to the Ith formal parameter of the
 410    function associated with INFO.  */
 411
 412 static inline bool
 413 ipa_is_param_used (struct ipa_node_params *info, int i)
 414 {
 415   return info->descriptors[i].used;
 416 }
 417
 418 /* Information about replacements done in aggregates for a given node (each
 419    node has its linked list).  */
 420 struct GTY(()) ipa_agg_replacement_value
 421 {
 422   /* Next item in the linked list.  */
 423   struct ipa_agg_replacement_value *next;
 424   /* Offset within the aggregate.  */
 425   HOST_WIDE_INT offset;
 426   /* The constant value.  */
 427   tree value;
 428   /* The paramter index.  */
 429   int index;
 430   /* Whether the value was passed by reference.  */
 431   bool by_ref;
 432 };
 433
 434 typedef struct ipa_agg_replacement_value *ipa_agg_replacement_value_p;
 435
 436 void ipa_set_node_agg_value_chain (struct cgraph_node *node,
 437                                    struct ipa_agg_replacement_value *aggvals);
 438
 439 /* ipa_edge_args stores information related to a callsite and particularly its
 440    arguments.  It can be accessed by the IPA_EDGE_REF macro.  */
 441 typedef struct GTY(()) ipa_edge_args
 442 {
 443   /* Vector of the callsite's jump function of each parameter.  */
 444   vec<ipa_jump_func_t, va_gc> *jump_functions;
 445 } ipa_edge_args_t;
 446
 447 /* ipa_edge_args access functions.  Please use these to access fields that
 448    are or will be shared among various passes.  */
 449
 450 /* Return the number of actual arguments. */
 451
 452 static inline int
 453 ipa_get_cs_argument_count (struct ipa_edge_args *args)
 454 {
 455   return vec_safe_length (args->jump_functions);
 456 }
 457
 458 /* Returns a pointer to the jump function for the ith argument.  Please note
 459    there is no setter function as jump functions are all set up in
 460    ipa_compute_jump_functions. */
 461
 462 static inline struct ipa_jump_func *
 463 ipa_get_ith_jump_func (struct ipa_edge_args *args, int i)
 464 {
 465   return &(*args->jump_functions)[i];
 466 }
 467
 468 /* Vectors need to have typedefs of structures.  */
 469 typedef struct ipa_node_params ipa_node_params_t;
 470
 471 /* Types of vectors holding the infos.  */
 472
 473 /* Vector where the parameter infos are actually stored. */
 474 extern vec<ipa_node_params_t> ipa_node_params_vector;
 475 /* Vector of known aggregate values in cloned nodes.  */
 476 extern GTY(()) vec<ipa_agg_replacement_value_p, va_gc> *ipa_node_agg_replacements;
 477 /* Vector where the parameter infos are actually stored. */
 478 extern GTY(()) vec<ipa_edge_args_t, va_gc> *ipa_edge_args_vector;
 479
 480 /* Return the associated parameter/argument info corresponding to the given
 481    node/edge.  */
 482 #define IPA_NODE_REF(NODE) (&ipa_node_params_vector[(NODE)->uid])
 483 #define IPA_EDGE_REF(EDGE) (&(*ipa_edge_args_vector)[(EDGE)->uid])
 484 /* This macro checks validity of index returned by
 485    ipa_get_param_decl_index function.  */
 486 #define IS_VALID_JUMP_FUNC_INDEX(I) ((I) != -1)
 487
 488 /* Creating and freeing ipa_node_params and ipa_edge_args.  */
 489 void ipa_create_all_node_params (void);
 490 void ipa_create_all_edge_args (void);
 491 void ipa_free_edge_args_substructures (struct ipa_edge_args *);
 492 void ipa_free_node_params_substructures (struct ipa_node_params *);
 493 void ipa_free_all_node_params (void);
 494 void ipa_free_all_edge_args (void);
 495 void ipa_free_all_structures_after_ipa_cp (void);
 496 void ipa_free_all_structures_after_iinln (void);
 497 void ipa_register_cgraph_hooks (void);
 498
 499 /* This function ensures the array of node param infos is big enough to
 500    accommodate a structure for all nodes and reallocates it if not.  */
 501
 502 static inline void
 503 ipa_check_create_node_params (void)
 504 {
 505   if (!ipa_node_params_vector.exists ())
 506     ipa_node_params_vector.create (cgraph_max_uid);
 507
 508   if (ipa_node_params_vector.length () <= (unsigned) cgraph_max_uid)
 509     ipa_node_params_vector.safe_grow_cleared (cgraph_max_uid + 1);
 510 }
 511
 512 /* This function ensures the array of edge arguments infos is big enough to
 513    accommodate a structure for all edges and reallocates it if not.  */
 514
 515 static inline void
 516 ipa_check_create_edge_args (void)
 517 {
 518   if (vec_safe_length (ipa_edge_args_vector) <= (unsigned) cgraph_edge_max_uid)
 519     vec_safe_grow_cleared (ipa_edge_args_vector, cgraph_edge_max_uid + 1);
 520 }
 521
 522 /* Returns true if the array of edge infos is large enough to accommodate an
 523    info for EDGE.  The main purpose of this function is that debug dumping
 524    function can check info availability without causing reallocations.  */
 525
 526 static inline bool
 527 ipa_edge_args_info_available_for_edge_p (struct cgraph_edge *edge)
 528 {
 529   return ((unsigned) edge->uid < vec_safe_length (ipa_edge_args_vector));
 530 }
 531
 532 /* Return the aggregate replacements for NODE, if there are any.  */
 533
 534 static inline struct ipa_agg_replacement_value *
 535 ipa_get_agg_replacements_for_node (struct cgraph_node *node)
 536 {
 537   if ((unsigned) node->uid >= vec_safe_length (ipa_node_agg_replacements))
 538     return NULL;
 539   return (*ipa_node_agg_replacements)[node->uid];
 540 }
 541
 542 /* Function formal parameters related computations.  */
 543 void ipa_initialize_node_params (struct cgraph_node *node);
 544 bool ipa_propagate_indirect_call_infos (struct cgraph_edge *cs,
 545                                         vec<cgraph_edge_p> *new_edges);
 546
 547 /* Indirect edge and binfo processing.  */
 548 tree ipa_get_indirect_edge_target (struct cgraph_edge *ie,
 549                                    vec<tree> ,
 550                                    vec<tree> ,
 551                                    vec<ipa_agg_jump_function_p> );
 552 struct cgraph_edge *ipa_make_edge_direct_to_target (struct cgraph_edge *, tree);
 553 tree ipa_binfo_from_known_type_jfunc (struct ipa_jump_func *);
 554 tree ipa_intraprocedural_devirtualization (gimple);
 555
 556 /* Functions related to both.  */
 557 void ipa_analyze_node (struct cgraph_node *);
 558
 559 /* Aggregate jump function related functions.  */
 560 tree ipa_find_agg_cst_for_param (struct ipa_agg_jump_function *, HOST_WIDE_INT,
 561                                  bool);
 562 bool ipa_load_from_parm_agg (struct ipa_node_params *, gimple, tree, int *,
 563                              HOST_WIDE_INT *, bool *);
 564
 565 /* Debugging interface.  */
 566 void ipa_print_node_params (FILE *, struct cgraph_node *node);
 567 void ipa_print_all_params (FILE *);
 568 void ipa_print_node_jump_functions (FILE *f, struct cgraph_node *node);
 569 void ipa_print_all_jump_functions (FILE * f);
 570 void ipcp_verify_propagated_values (void);
 571
 572 extern alloc_pool ipcp_values_pool;
 573 extern alloc_pool ipcp_sources_pool;
 574 extern alloc_pool ipcp_agg_lattice_pool;
 575
 576 /* Structure to describe transformations of formal parameters and actual
 577    arguments.  Each instance describes one new parameter and they are meant to
 578    be stored in a vector.  Additionally, most users will probably want to store
 579    adjustments about parameters that are being removed altogether so that SSA
 580    names belonging to them can be replaced by SSA names of an artificial
 581    variable.  */
 582 struct ipa_parm_adjustment
 583 {
 584   /* The original PARM_DECL itself, helpful for processing of the body of the
 585      function itself.  Intended for traversing function bodies.
 586      ipa_modify_formal_parameters, ipa_modify_call_arguments and
 587      ipa_combine_adjustments ignore this and use base_index.
 588      ipa_modify_formal_parameters actually sets this.  */
 589   tree base;
 590
 591   /* Type of the new parameter.  However, if by_ref is true, the real type will
 592      be a pointer to this type.  */
 593   tree type;
 594
 595   /* Alias refrerence type to be used in MEM_REFs when adjusting caller
 596      arguments.  */
 597   tree alias_ptr_type;
 598
 599   /* The new declaration when creating/replacing a parameter.  Created by
 600      ipa_modify_formal_parameters, useful for functions modifying the body
 601      accordingly. */
 602   tree reduction;
 603
 604   /* New declaration of a substitute variable that we may use to replace all
 605      non-default-def ssa names when a parm decl is going away.  */
 606   tree new_ssa_base;
 607
 608   /* If non-NULL and the original parameter is to be removed (copy_param below
 609      is NULL), this is going to be its nonlocalized vars value.  */
 610   tree nonlocal_value;
 611
 612   /* Offset into the original parameter (for the cases when the new parameter
 613      is a component of an original one).  */
 614   HOST_WIDE_INT offset;
 615
 616   /* Zero based index of the original parameter this one is based on.  (ATM
 617      there is no way to insert a new parameter out of the blue because there is
 618      no need but if it arises the code can be easily exteded to do so.)  */
 619   int base_index;
 620
 621   /* This new parameter is an unmodified parameter at index base_index. */
 622   unsigned copy_param : 1;
 623
 624   /* This adjustment describes a parameter that is about to be removed
 625      completely.  Most users will probably need to book keep those so that they
 626      don't leave behinfd any non default def ssa names belonging to them.  */
 627   unsigned remove_param : 1;
 628
 629   /* The parameter is to be passed by reference.  */
 630   unsigned by_ref : 1;
 631 };
 632
 633 typedef struct ipa_parm_adjustment ipa_parm_adjustment_t;
 634
 635 typedef vec<ipa_parm_adjustment_t> ipa_parm_adjustment_vec;
 636
 637 vec<tree> ipa_get_vector_of_formal_parms (tree fndecl);
 638 void ipa_modify_formal_parameters (tree fndecl, ipa_parm_adjustment_vec,
 639                                    const char *);
 640 void ipa_modify_call_arguments (struct cgraph_edge *, gimple,
 641                                 ipa_parm_adjustment_vec);
 642 ipa_parm_adjustment_vec ipa_combine_adjustments (ipa_parm_adjustment_vec,
 643                                                  ipa_parm_adjustment_vec);
 644 void ipa_dump_param_adjustments (FILE *, ipa_parm_adjustment_vec, tree);
 645 void ipa_dump_agg_replacement_values (FILE *f,
 646                                       struct ipa_agg_replacement_value *av);
 647 void ipa_prop_write_jump_functions (void);
 648 void ipa_prop_read_jump_functions (void);
 649 void ipa_prop_write_all_agg_replacement (void);
 650 void ipa_prop_read_all_agg_replacement (void);
 651 void ipa_update_after_lto_read (void);
 652 int ipa_get_param_decl_index (struct ipa_node_params *, tree);
 653 tree ipa_value_from_jfunc (struct ipa_node_params *info,
 654                            struct ipa_jump_func *jfunc);
 655 unsigned int ipcp_transform_function (struct cgraph_node *node);
 656
 657
 658 /* From tree-sra.c:  */
 659 tree build_ref_for_offset (location_t, tree, HOST_WIDE_INT, tree,
 660                            gimple_stmt_iterator *, bool);
 661
 662 #endif /* IPA_PROP_H */