gcc/ipa-prop.h

   1 /* Interprocedural analyses.
   2    Copyright (C) 2005, 2007, 2008, 2009, 2010
   3    Free Software Foundation, Inc.
   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 3, 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 COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #ifndef IPA_PROP_H
  22 #define IPA_PROP_H
  23
  24 #include "tree.h"
  25 #include "vec.h"
  26 #include "cgraph.h"
  27 #include "gimple.h"
  28 #include "alloc-pool.h"
  29
  30 /* The following definitions and interfaces are used by
  31    interprocedural analyses or parameters.  */
  32
  33 /* ipa-prop.c stuff (ipa-cp, indirect inlining):  */
  34
  35 /* A jump function for a callsite represents the values passed as actual
  36    arguments of the callsite.  They were originally proposed in a paper called
  37    "Interprocedural Constant Propagation", by David Callahan, Keith D Cooper,
  38    Ken Kennedy, Linda Torczon in Comp86, pg 152-161.  There are three main
  39    types of values :
  40
  41    Pass-through - the caller's formal parameter is passed as an actual
  42                   argument, possibly one simple operation performed on it.
  43    Constant     - a constant (is_gimple_ip_invariant)is passed as an actual
  44                   argument.
  45    Unknown      - neither of the above.
  46
  47    IPA_JF_ANCESTOR is a special pass-through jump function, which means that
  48    the result is an address of a part of the object pointed to by the formal
  49    parameter to which the function refers.  It is mainly intended to represent
  50    getting addresses of of ancestor fields in C++
  51    (e.g. &this_1(D)->D.1766.D.1756).  Note that if the original pointer is
  52    NULL, ancestor jump function must behave like a simple pass-through.
  53
  54    Other pass-through functions can either simply pass on an unchanged formal
  55    parameter or can apply one simple binary operation to it (such jump
  56    functions are called polynomial).
  57
  58    IPA_JF_KNOWN_TYPE is a special type of an "unknown" function that applies
  59    only to pointer parameters.  It means that even though we cannot prove that
  60    the passed value is an interprocedural constant, we still know the exact
  61    type of the containing object which may be valuable for devirtualization.
  62
  63    Jump functions are computed in ipa-prop.c by function
  64    update_call_notes_after_inlining.  Some information can be lost and jump
  65    functions degraded accordingly when inlining, see
  66    update_call_notes_after_inlining in the same file.  */
  67
  68 enum jump_func_type
  69 {
  70   IPA_JF_UNKNOWN = 0,  /* newly allocated and zeroed jump functions default */
  71   IPA_JF_KNOWN_TYPE,        /* represented by field known_type */
  72   IPA_JF_CONST,             /* represented by field costant */
  73   IPA_JF_PASS_THROUGH,      /* represented by field pass_through */
  74   IPA_JF_ANCESTOR           /* represented by field ancestor */
  75 };
  76
  77 /* Structure holding data required to describe a known type jump function.  */
  78 struct GTY(()) ipa_known_type_data
  79 {
  80   /* Offset of the component of the base_type being described.  */
  81   HOST_WIDE_INT offset;
  82   /* Type of the whole object.  */
  83   tree base_type;
  84   /* Type of the component of the object that is being described.  */
  85   tree component_type;
  86 };
  87
  88 /* Structure holding data required to describe a pass-through jump function.  */
  89
  90 struct GTY(()) ipa_pass_through_data
  91 {
  92   /* If an operation is to be performed on the original parameter, this is the
  93      second (constant) operand.  */
  94   tree operand;
  95   /* Number of the caller's formal parameter being passed.  */
  96   int formal_id;
  97   /* Operation that is performed on the argument before it is passed on.
  98      NOP_EXPR means no operation.  Otherwise oper must be a simple binary
  99      arithmetic operation where the caller's parameter is the first operand and
 100      operand field from this structure is the second one.  */
 101   enum tree_code operation;
 102   /* When the passed value is a pointer, it is set to true only when we are
 103      certain that no write to the object it points to has occurred since the
 104      caller functions started execution, except for changes noted in the
 105      aggregate part of the jump function (see description of
 106      ipa_agg_jump_function).  The flag is used only when the operation is
 107      NOP_EXPR.  */
 108   bool agg_preserved;
 109 };
 110
 111 /* Structure holding data required to describe an ancestor pass-through
 112    jump function.  */
 113
 114 struct GTY(()) ipa_ancestor_jf_data
 115 {
 116   /* Offset of the field representing the ancestor.  */
 117   HOST_WIDE_INT offset;
 118   /* Type of the result.  */
 119   tree type;
 120   /* Number of the caller's formal parameter being passed.  */
 121   int formal_id;
 122   /* Flag with the same meaning like agg_preserve in ipa_pass_through_data.  */
 123   bool agg_preserved;
 124 };
 125
 126 /* An element in an aggegate part of a jump function describing a known value
 127    at a given offset.  When it is part of a pass-through jump function with
 128    agg_preserved set or an ancestor jump function with agg_preserved set, all
 129    unlisted positions are assumed to be preserved but the value can be a type
 130    node, which means that the particular piece (starting at offset and having
 131    the size of the type) is clobbered with an unknown value.  When
 132    agg_preserved is false or the type of the containing jump function is
 133    different, all unlisted parts are assumed to be unknown and all values must
 134    fullfill is_gimple_ip_invariant.  */
 135
 136 typedef struct GTY(()) ipa_agg_jf_item
 137 {
 138   /* The offset at which the known value is located within the aggregate.  */
 139   HOST_WIDE_INT offset;
 140
 141   /* The known constant or type if this is a clobber.  */
 142   tree value;
 143 } ipa_agg_jf_item_t;
 144
 145 DEF_VEC_O (ipa_agg_jf_item_t);
 146 DEF_VEC_ALLOC_O (ipa_agg_jf_item_t, gc);
 147 DEF_VEC_ALLOC_O (ipa_agg_jf_item_t, heap);
 148
 149 /* Aggregate jump function - i.e. description of contents of aggregates passed
 150    either by reference or value.  */
 151
 152 struct GTY(()) ipa_agg_jump_function
 153 {
 154   /* Description of the individual items.  */
 155   VEC (ipa_agg_jf_item_t, gc) *items;
 156   /* True if the data was passed by reference (as opposed to by value). */
 157   bool by_ref;
 158 };
 159
 160 typedef struct ipa_agg_jump_function *ipa_agg_jump_function_p;
 161 DEF_VEC_P (ipa_agg_jump_function_p);
 162 DEF_VEC_ALLOC_P (ipa_agg_jump_function_p, heap);
 163 typedef struct ipa_agg_jump_function ipa_agg_jump_function_t;
 164 DEF_VEC_P (ipa_agg_jump_function_t);
 165 DEF_VEC_ALLOC_P (ipa_agg_jump_function_t, heap);
 166
 167 /* A jump function for a callsite represents the values passed as actual
 168    arguments of the callsite. See enum jump_func_type for the various
 169    types of jump functions supported.  */
 170 typedef struct GTY (()) ipa_jump_func
 171 {
 172   /* Aggregate contants description.  See struct ipa_agg_jump_function and its
 173      description.  */
 174   struct ipa_agg_jump_function agg;
 175
 176   enum jump_func_type type;
 177   /* Represents a value of a jump function.  pass_through is used only in jump
 178      function context.  constant represents the actual constant in constant jump
 179      functions and member_cst holds constant c++ member functions.  */
 180   union jump_func_value
 181   {
 182     struct ipa_known_type_data GTY ((tag ("IPA_JF_KNOWN_TYPE"))) known_type;
 183     tree GTY ((tag ("IPA_JF_CONST"))) constant;
 184     struct ipa_pass_through_data GTY ((tag ("IPA_JF_PASS_THROUGH"))) pass_through;
 185     struct ipa_ancestor_jf_data GTY ((tag ("IPA_JF_ANCESTOR"))) ancestor;
 186   } GTY ((desc ("%1.type"))) value;
 187 } ipa_jump_func_t;
 188
 189 DEF_VEC_O (ipa_jump_func_t);
 190 DEF_VEC_ALLOC_O (ipa_jump_func_t, gc);
 191
 192 /* Return the offset of the component that is decribed by a known type jump
 193    function JFUNC.  */
 194
 195 static inline HOST_WIDE_INT
 196 ipa_get_jf_known_type_offset (struct ipa_jump_func *jfunc)
 197 {
 198   gcc_checking_assert (jfunc->type == IPA_JF_KNOWN_TYPE);
 199   return jfunc->value.known_type.offset;
 200 }
 201
 202 /* Return the base type of a known type jump function JFUNC.  */
 203
 204 static inline tree
 205 ipa_get_jf_known_type_base_type (struct ipa_jump_func *jfunc)
 206 {
 207   gcc_checking_assert (jfunc->type == IPA_JF_KNOWN_TYPE);
 208   return jfunc->value.known_type.base_type;
 209 }
 210
 211 /* Return the component type of a known type jump function JFUNC.  */
 212
 213 static inline tree
 214 ipa_get_jf_known_type_component_type (struct ipa_jump_func *jfunc)
 215 {
 216   gcc_checking_assert (jfunc->type == IPA_JF_KNOWN_TYPE);
 217   return jfunc->value.known_type.component_type;
 218 }
 219
 220 /* Return the constant stored in a constant jump functin JFUNC.  */
 221
 222 static inline tree
 223 ipa_get_jf_constant (struct ipa_jump_func *jfunc)
 224 {
 225   gcc_checking_assert (jfunc->type == IPA_JF_CONST);
 226   return jfunc->value.constant;
 227 }
 228
 229 /* Return the operand of a pass through jmp function JFUNC.  */
 230
 231 static inline tree
 232 ipa_get_jf_pass_through_operand (struct ipa_jump_func *jfunc)
 233 {
 234   gcc_checking_assert (jfunc->type == IPA_JF_PASS_THROUGH);
 235   return jfunc->value.pass_through.operand;
 236 }
 237
 238 /* Return the number of the caller's formal parameter that a pass through jump
 239    function JFUNC refers to.  */
 240
 241 static inline int
 242 ipa_get_jf_pass_through_formal_id (struct ipa_jump_func *jfunc)
 243 {
 244   gcc_checking_assert (jfunc->type == IPA_JF_PASS_THROUGH);
 245   return jfunc->value.pass_through.formal_id;
 246 }
 247
 248 /* Return operation of a pass through jump function JFUNC.  */
 249
 250 static inline enum tree_code
 251 ipa_get_jf_pass_through_operation (struct ipa_jump_func *jfunc)
 252 {
 253   gcc_checking_assert (jfunc->type == IPA_JF_PASS_THROUGH);
 254   return jfunc->value.pass_through.operation;
 255 }
 256
 257 /* Return the agg_preserved flag of a pass through jump functin JFUNC.  */
 258
 259 static inline bool
 260 ipa_get_jf_pass_through_agg_preserved (struct ipa_jump_func *jfunc)
 261 {
 262   gcc_checking_assert (jfunc->type == IPA_JF_PASS_THROUGH);
 263   return jfunc->value.pass_through.agg_preserved;
 264 }
 265
 266 /* Return the offset of an ancestor jump function JFUNC.  */
 267
 268 static inline HOST_WIDE_INT
 269 ipa_get_jf_ancestor_offset (struct ipa_jump_func *jfunc)
 270 {
 271   gcc_checking_assert (jfunc->type == IPA_JF_ANCESTOR);
 272   return jfunc->value.ancestor.offset;
 273 }
 274
 275 /* Return the result type of an ancestor jump function JFUNC.  */
 276
 277 static inline tree
 278 ipa_get_jf_ancestor_type (struct ipa_jump_func *jfunc)
 279 {
 280   gcc_checking_assert (jfunc->type == IPA_JF_ANCESTOR);
 281   return jfunc->value.ancestor.type;
 282 }
 283
 284 /* Return the number of the caller's formal parameter that an ancestor jump
 285    function JFUNC refers to.  */
 286
 287 static inline int
 288 ipa_get_jf_ancestor_formal_id (struct ipa_jump_func *jfunc)
 289 {
 290   gcc_checking_assert (jfunc->type == IPA_JF_ANCESTOR);
 291   return jfunc->value.ancestor.formal_id;
 292 }
 293
 294 /* Return the agg_preserved flag of an ancestor jump functin JFUNC.  */
 295
 296 static inline bool
 297 ipa_get_jf_ancestor_agg_preserved (struct ipa_jump_func *jfunc)
 298 {
 299   gcc_checking_assert (jfunc->type == IPA_JF_ANCESTOR);
 300   return jfunc->value.ancestor.agg_preserved;
 301 }
 302
 303 /* Summary describing a single formal parameter.  */
 304
 305 struct ipa_param_descriptor
 306 {
 307   /* PARAM_DECL of this parameter.  */
 308   tree decl;
 309   /* The parameter is used.  */
 310   unsigned used : 1;
 311 };
 312
 313 typedef struct ipa_param_descriptor ipa_param_descriptor_t;
 314 DEF_VEC_O (ipa_param_descriptor_t);
 315 DEF_VEC_ALLOC_O (ipa_param_descriptor_t, heap);
 316 struct ipcp_lattice;
 317
 318 /* ipa_node_params stores information related to formal parameters of functions
 319    and some other information for interprocedural passes that operate on
 320    parameters (such as ipa-cp).  */
 321
 322 struct ipa_node_params
 323 {
 324   /* Information about individual formal parameters that are gathered when
 325      summaries are generated. */
 326   VEC (ipa_param_descriptor_t, heap) *descriptors;
 327   /* Pointer to an array of structures describing individual formal
 328      parameters.  */
 329   struct ipcp_param_lattices *lattices;
 330   /* Only for versioned nodes this field would not be NULL,
 331      it points to the node that IPA cp cloned from.  */
 332   struct cgraph_node *ipcp_orig_node;
 333   /* If this node is an ipa-cp clone, these are the known values that describe
 334      what it has been specialized for.  */
 335   VEC (tree, heap) *known_vals;
 336   /* Whether the param uses analysis has already been performed.  */
 337   unsigned uses_analysis_done : 1;
 338   /* Whether the function is enqueued in ipa-cp propagation stack.  */
 339   unsigned node_enqueued : 1;
 340   /* Whether we should create a specialized version based on values that are
 341      known to be constant in all contexts.  */
 342   unsigned clone_for_all_contexts : 1;
 343   /* Node has been completely replaced by clones and will be removed after
 344      ipa-cp is finished.  */
 345   unsigned node_dead : 1;
 346 };
 347
 348 /* ipa_node_params access functions.  Please use these to access fields that
 349    are or will be shared among various passes.  */
 350
 351 /* Return the number of formal parameters. */
 352
 353 static inline int
 354 ipa_get_param_count (struct ipa_node_params *info)
 355 {
 356   return VEC_length (ipa_param_descriptor_t, info->descriptors);
 357 }
 358
 359 /* Return the declaration of Ith formal parameter of the function corresponding
 360    to INFO.  Note there is no setter function as this array is built just once
 361    using ipa_initialize_node_params. */
 362
 363 static inline tree
 364 ipa_get_param (struct ipa_node_params *info, int i)
 365 {
 366   return VEC_index (ipa_param_descriptor_t, info->descriptors, i).decl;
 367 }
 368
 369 /* Set the used flag corresponding to the Ith formal parameter of the function
 370    associated with INFO to VAL.  */
 371
 372 static inline void
 373 ipa_set_param_used (struct ipa_node_params *info, int i, bool val)
 374 {
 375   VEC_index (ipa_param_descriptor_t, info->descriptors, i).used = val;
 376 }
 377
 378 /* Return the used flag corresponding to the Ith formal parameter of the
 379    function associated with INFO.  */
 380
 381 static inline bool
 382 ipa_is_param_used (struct ipa_node_params *info, int i)
 383 {
 384   return VEC_index (ipa_param_descriptor_t, info->descriptors, i).used;
 385 }
 386
 387 /* Information about replacements done in aggregates for a given node (each
 388    node has its linked list).  */
 389 struct GTY(()) ipa_agg_replacement_value
 390 {
 391   /* Next item in the linked list.  */
 392   struct ipa_agg_replacement_value *next;
 393   /* Offset within the aggregate.  */
 394   HOST_WIDE_INT offset;
 395   /* The constant value.  */
 396   tree value;
 397   /* The paramter index.  */
 398   int index;
 399 };
 400
 401 typedef struct ipa_agg_replacement_value *ipa_agg_replacement_value_p;
 402 DEF_VEC_P (ipa_agg_replacement_value_p);
 403 DEF_VEC_ALLOC_P (ipa_agg_replacement_value_p, gc);
 404
 405 void ipa_set_node_agg_value_chain (struct cgraph_node *node,
 406                                    struct ipa_agg_replacement_value *aggvals);
 407
 408 /* ipa_edge_args stores information related to a callsite and particularly its
 409    arguments.  It can be accessed by the IPA_EDGE_REF macro.  */
 410 typedef struct GTY(()) ipa_edge_args
 411 {
 412   /* Vector of the callsite's jump function of each parameter.  */
 413   VEC (ipa_jump_func_t, gc) *jump_functions;
 414 } ipa_edge_args_t;
 415
 416 /* ipa_edge_args access functions.  Please use these to access fields that
 417    are or will be shared among various passes.  */
 418
 419 /* Return the number of actual arguments. */
 420
 421 static inline int
 422 ipa_get_cs_argument_count (struct ipa_edge_args *args)
 423 {
 424   return VEC_length (ipa_jump_func_t, args->jump_functions);
 425 }
 426
 427 /* Returns a pointer to the jump function for the ith argument.  Please note
 428    there is no setter function as jump functions are all set up in
 429    ipa_compute_jump_functions. */
 430
 431 static inline struct ipa_jump_func *
 432 ipa_get_ith_jump_func (struct ipa_edge_args *args, int i)
 433 {
 434   return &VEC_index (ipa_jump_func_t, args->jump_functions, i);
 435 }
 436
 437 /* Vectors need to have typedefs of structures.  */
 438 typedef struct ipa_node_params ipa_node_params_t;
 439
 440 /* Types of vectors holding the infos.  */
 441 DEF_VEC_O (ipa_node_params_t);
 442 DEF_VEC_ALLOC_O (ipa_node_params_t, heap);
 443 DEF_VEC_O (ipa_edge_args_t);
 444 DEF_VEC_ALLOC_O (ipa_edge_args_t, gc);
 445
 446 /* Vector where the parameter infos are actually stored. */
 447 extern VEC (ipa_node_params_t, heap) *ipa_node_params_vector;
 448 /* Vector of known aggregate values in cloned nodes.  */
 449 extern GTY(()) VEC (ipa_agg_replacement_value_p, gc) *ipa_node_agg_replacements;
 450 /* Vector where the parameter infos are actually stored. */
 451 extern GTY(()) VEC (ipa_edge_args_t, gc) *ipa_edge_args_vector;
 452
 453 /* Return the associated parameter/argument info corresponding to the given
 454    node/edge.  */
 455 #define IPA_NODE_REF(NODE) (&VEC_index (ipa_node_params_t, \
 456                                         ipa_node_params_vector, (NODE)->uid))
 457 #define IPA_EDGE_REF(EDGE) (&VEC_index (ipa_edge_args_t, \
 458                                         ipa_edge_args_vector, (EDGE)->uid))
 459 /* This macro checks validity of index returned by
 460    ipa_get_param_decl_index function.  */
 461 #define IS_VALID_JUMP_FUNC_INDEX(I) ((I) != -1)
 462
 463 /* Creating and freeing ipa_node_params and ipa_edge_args.  */
 464 void ipa_create_all_node_params (void);
 465 void ipa_create_all_edge_args (void);
 466 void ipa_free_edge_args_substructures (struct ipa_edge_args *);
 467 void ipa_free_node_params_substructures (struct ipa_node_params *);
 468 void ipa_free_all_node_params (void);
 469 void ipa_free_all_edge_args (void);
 470 void ipa_free_all_structures_after_ipa_cp (void);
 471 void ipa_free_all_structures_after_iinln (void);
 472 void ipa_register_cgraph_hooks (void);
 473
 474 /* This function ensures the array of node param infos is big enough to
 475    accommodate a structure for all nodes and reallocates it if not.  */
 476
 477 static inline void
 478 ipa_check_create_node_params (void)
 479 {
 480   if (!ipa_node_params_vector)
 481     ipa_node_params_vector = VEC_alloc (ipa_node_params_t, heap,
 482                                         cgraph_max_uid);
 483
 484   if (VEC_length (ipa_node_params_t, ipa_node_params_vector)
 485       <= (unsigned) cgraph_max_uid)
 486     VEC_safe_grow_cleared (ipa_node_params_t, heap,
 487                            ipa_node_params_vector, cgraph_max_uid + 1);
 488 }
 489
 490 /* This function ensures the array of edge arguments infos is big enough to
 491    accommodate a structure for all edges and reallocates it if not.  */
 492
 493 static inline void
 494 ipa_check_create_edge_args (void)
 495 {
 496   if (!ipa_edge_args_vector)
 497     ipa_edge_args_vector = VEC_alloc (ipa_edge_args_t, gc,
 498                                       cgraph_edge_max_uid);
 499
 500   if (VEC_length (ipa_edge_args_t, ipa_edge_args_vector)
 501       <=  (unsigned) cgraph_edge_max_uid)
 502     VEC_safe_grow_cleared (ipa_edge_args_t, gc, ipa_edge_args_vector,
 503                            cgraph_edge_max_uid + 1);
 504 }
 505
 506 /* Returns true if the array of edge infos is large enough to accommodate an
 507    info for EDGE.  The main purpose of this function is that debug dumping
 508    function can check info availability without causing reallocations.  */
 509
 510 static inline bool
 511 ipa_edge_args_info_available_for_edge_p (struct cgraph_edge *edge)
 512 {
 513   return ((unsigned) edge->uid < VEC_length (ipa_edge_args_t,
 514                                              ipa_edge_args_vector));
 515 }
 516
 517 /* Return the aggregate replacements for NODE, if there are any.  */
 518
 519 static inline struct ipa_agg_replacement_value *
 520 ipa_get_agg_replacements_for_node (struct cgraph_node *node)
 521 {
 522   if ((unsigned) node->uid >= VEC_length (ipa_agg_replacement_value_p,
 523                                           ipa_node_agg_replacements))
 524     return NULL;
 525   return VEC_index (ipa_agg_replacement_value_p, ipa_node_agg_replacements,
 526                     node->uid);
 527 }
 528
 529 /* Function formal parameters related computations.  */
 530 void ipa_initialize_node_params (struct cgraph_node *node);
 531 bool ipa_propagate_indirect_call_infos (struct cgraph_edge *cs,
 532                                         VEC (cgraph_edge_p, heap) **new_edges);
 533
 534 /* Indirect edge and binfo processing.  */
 535 tree ipa_get_indirect_edge_target (struct cgraph_edge *ie,
 536                                    VEC (tree, heap) *,
 537                                    VEC (tree, heap) *,
 538                                    VEC (ipa_agg_jump_function_p, heap) *);
 539 struct cgraph_edge *ipa_make_edge_direct_to_target (struct cgraph_edge *, tree);
 540
 541 /* Functions related to both.  */
 542 void ipa_analyze_node (struct cgraph_node *);
 543
 544 /* Aggregate jump function related functions.  */
 545 tree ipa_find_agg_cst_for_param (struct ipa_agg_jump_function *, HOST_WIDE_INT,
 546                                  bool);
 547 bool ipa_load_from_parm_agg (struct ipa_node_params *, gimple, tree, int *,
 548                              HOST_WIDE_INT *, bool *);
 549
 550 /* Debugging interface.  */
 551 void ipa_print_node_params (FILE *, struct cgraph_node *node);
 552 void ipa_print_all_params (FILE *);
 553 void ipa_print_node_jump_functions (FILE *f, struct cgraph_node *node);
 554 void ipa_print_all_jump_functions (FILE * f);
 555 void ipcp_verify_propagated_values (void);
 556
 557 extern alloc_pool ipcp_values_pool;
 558 extern alloc_pool ipcp_sources_pool;
 559 extern alloc_pool ipcp_agg_lattice_pool;
 560
 561 /* Structure to describe transformations of formal parameters and actual
 562    arguments.  Each instance describes one new parameter and they are meant to
 563    be stored in a vector.  Additionally, most users will probably want to store
 564    adjustments about parameters that are being removed altogether so that SSA
 565    names belonging to them can be replaced by SSA names of an artificial
 566    variable.  */
 567 struct ipa_parm_adjustment
 568 {
 569   /* The original PARM_DECL itself, helpful for processing of the body of the
 570      function itself.  Intended for traversing function bodies.
 571      ipa_modify_formal_parameters, ipa_modify_call_arguments and
 572      ipa_combine_adjustments ignore this and use base_index.
 573      ipa_modify_formal_parameters actually sets this.  */
 574   tree base;
 575
 576   /* Type of the new parameter.  However, if by_ref is true, the real type will
 577      be a pointer to this type.  */
 578   tree type;
 579
 580   /* Alias refrerence type to be used in MEM_REFs when adjusting caller
 581      arguments.  */
 582   tree alias_ptr_type;
 583
 584   /* The new declaration when creating/replacing a parameter.  Created by
 585      ipa_modify_formal_parameters, useful for functions modifying the body
 586      accordingly. */
 587   tree reduction;
 588
 589   /* New declaration of a substitute variable that we may use to replace all
 590      non-default-def ssa names when a parm decl is going away.  */
 591   tree new_ssa_base;
 592
 593   /* If non-NULL and the original parameter is to be removed (copy_param below
 594      is NULL), this is going to be its nonlocalized vars value.  */
 595   tree nonlocal_value;
 596
 597   /* Offset into the original parameter (for the cases when the new parameter
 598      is a component of an original one).  */
 599   HOST_WIDE_INT offset;
 600
 601   /* Zero based index of the original parameter this one is based on.  (ATM
 602      there is no way to insert a new parameter out of the blue because there is
 603      no need but if it arises the code can be easily exteded to do so.)  */
 604   int base_index;
 605
 606   /* This new parameter is an unmodified parameter at index base_index. */
 607   unsigned copy_param : 1;
 608
 609   /* This adjustment describes a parameter that is about to be removed
 610      completely.  Most users will probably need to book keep those so that they
 611      don't leave behinfd any non default def ssa names belonging to them.  */
 612   unsigned remove_param : 1;
 613
 614   /* The parameter is to be passed by reference.  */
 615   unsigned by_ref : 1;
 616 };
 617
 618 typedef struct ipa_parm_adjustment ipa_parm_adjustment_t;
 619 DEF_VEC_O (ipa_parm_adjustment_t);
 620 DEF_VEC_ALLOC_O (ipa_parm_adjustment_t, heap);
 621
 622 typedef VEC (ipa_parm_adjustment_t, heap) *ipa_parm_adjustment_vec;
 623
 624 VEC(tree, heap) *ipa_get_vector_of_formal_parms (tree fndecl);
 625 void ipa_modify_formal_parameters (tree fndecl, ipa_parm_adjustment_vec,
 626                                    const char *);
 627 void ipa_modify_call_arguments (struct cgraph_edge *, gimple,
 628                                 ipa_parm_adjustment_vec);
 629 ipa_parm_adjustment_vec ipa_combine_adjustments (ipa_parm_adjustment_vec,
 630                                                  ipa_parm_adjustment_vec);
 631 void ipa_dump_param_adjustments (FILE *, ipa_parm_adjustment_vec, tree);
 632 void ipa_dump_agg_replacement_values (FILE *f,
 633                                       struct ipa_agg_replacement_value *av);
 634 void ipa_prop_write_jump_functions (void);
 635 void ipa_prop_read_jump_functions (void);
 636 void ipa_prop_write_all_agg_replacement (void);
 637 void ipa_prop_read_all_agg_replacement (void);
 638 void ipa_update_after_lto_read (void);
 639 int ipa_get_param_decl_index (struct ipa_node_params *, tree);
 640 tree ipa_value_from_jfunc (struct ipa_node_params *info,
 641                            struct ipa_jump_func *jfunc);
 642 unsigned int ipcp_transform_function (struct cgraph_node *node);
 643
 644
 645 /* From tree-sra.c:  */
 646 tree build_ref_for_offset (location_t, tree, HOST_WIDE_INT, tree,
 647                            gimple_stmt_iterator *, bool);
 648
 649 #endif /* IPA_PROP_H */