gcc/cgraph.h

   1 /* Callgraph handling code.
   2    Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008
   3    Free Software Foundation, Inc.
   4    Contributed by Jan Hubicka
   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_CGRAPH_H
  23 #define GCC_CGRAPH_H
  24 #include "tree.h"
  25 #include "basic-block.h"
  26
  27 enum availability
  28 {
  29   /* Not yet set by cgraph_function_body_availability.  */
  30   AVAIL_UNSET,
  31   /* Function body/variable initializer is unknown.  */
  32   AVAIL_NOT_AVAILABLE,
  33   /* Function body/variable initializer is known but might be replaced
  34      by a different one from other compilation unit and thus needs to
  35      be dealt with a care.  Like AVAIL_NOT_AVAILABLE it can have
  36      arbitrary side effects on escaping variables and functions, while
  37      like AVAILABLE it might access static variables.  */
  38   AVAIL_OVERWRITABLE,
  39   /* Function body/variable initializer is known and will be used in final
  40      program.  */
  41   AVAIL_AVAILABLE,
  42   /* Function body/variable initializer is known and all it's uses are explicitly
  43      visible within current unit (ie it's address is never taken and it is not
  44      exported to other units).
  45      Currently used only for functions.  */
  46   AVAIL_LOCAL
  47 };
  48
  49 extern const char * const cgraph_availability_names[];
  50
  51 /* Information about the function collected locally.
  52    Available after function is analyzed.  */
  53
  54 struct cgraph_local_info GTY(())
  55 {
  56   struct inline_summary {
  57     /* Estimated stack frame consumption by the function.  */
  58     HOST_WIDE_INT estimated_self_stack_size;
  59
  60     /* Size of the function before inlining.  */
  61     int self_insns;
  62   } inline_summary;
  63
  64   /* Set when function function is visible in current compilation unit only
  65      and its address is never taken.  */
  66   unsigned local : 1;
  67
  68   /* Set when function is visible by other units.  */
  69   unsigned externally_visible : 1;
  70
  71   /* Set once it has been finalized so we consider it to be output.  */
  72   unsigned finalized : 1;
  73
  74   /* False when there something makes inlining impossible (such as va_arg).  */
  75   unsigned inlinable : 1;
  76
  77   /* True when function should be inlined independently on its size.  */
  78   unsigned disregard_inline_limits : 1;
  79
  80   /* True when the function has been originally extern inline, but it is
  81      redefined now.  */
  82   unsigned redefined_extern_inline : 1;
  83
  84   /* True if statics_read_for_function and
  85      statics_written_for_function contain valid data.  */
  86   unsigned for_functions_valid : 1;
  87
  88   /* True if the function is going to be emitted in some other translation
  89      unit, referenced from vtable.  */
  90   unsigned vtable_method : 1;
  91 };
  92
  93 /* Information about the function that needs to be computed globally
  94    once compilation is finished.  Available only with -funit-at-a-time.  */
  95
  96 struct cgraph_global_info GTY(())
  97 {
  98   /* Estimated stack frame consumption by the function.  */
  99   HOST_WIDE_INT estimated_stack_size;
 100   /* Expected offset of the stack frame of inlined function.  */
 101   HOST_WIDE_INT stack_frame_offset;
 102
 103   /* For inline clones this points to the function they will be
 104      inlined into.  */
 105   struct cgraph_node *inlined_to;
 106
 107   /* Estimated size of the function after inlining.  */
 108   int insns;
 109
 110   /* Estimated growth after inlining.  INT_MIN if not computed.  */
 111   int estimated_growth;
 112
 113   /* Set iff the function has been inlined at least once.  */
 114   bool inlined;
 115 };
 116
 117 /* Information about the function that is propagated by the RTL backend.
 118    Available only for functions that has been already assembled.  */
 119
 120 struct cgraph_rtl_info GTY(())
 121 {
 122    unsigned int preferred_incoming_stack_boundary;
 123 };
 124
 125 /* The cgraph data structure.
 126    Each function decl has assigned cgraph_node listing callees and callers.  */
 127
 128 struct cgraph_node GTY((chain_next ("%h.next"), chain_prev ("%h.previous")))
 129 {
 130   tree decl;
 131   struct cgraph_edge *callees;
 132   struct cgraph_edge *callers;
 133   struct cgraph_node *next;
 134   struct cgraph_node *previous;
 135   /* For nested functions points to function the node is nested in.  */
 136   struct cgraph_node *origin;
 137   /* Points to first nested function, if any.  */
 138   struct cgraph_node *nested;
 139   /* Pointer to the next function with same origin, if any.  */
 140   struct cgraph_node *next_nested;
 141   /* Pointer to the next function in cgraph_nodes_queue.  */
 142   struct cgraph_node *next_needed;
 143   /* Pointer to the next clone.  */
 144   struct cgraph_node *next_clone;
 145   struct cgraph_node *prev_clone;
 146   /* For functions with many calls sites it holds map from call expression
 147      to the edge to speed up cgraph_edge function.  */
 148   htab_t GTY((param_is (struct cgraph_edge))) call_site_hash;
 149
 150   PTR GTY ((skip)) aux;
 151
 152   struct cgraph_local_info local;
 153   struct cgraph_global_info global;
 154   struct cgraph_rtl_info rtl;
 155
 156   /* Expected number of executions: calculated in profile.c.  */
 157   gcov_type count;
 158   /* Unique id of the node.  */
 159   int uid;
 160   /* Ordering of all cgraph nodes.  */
 161   int order;
 162
 163   /* unique id for profiling. pid is not suitable because of different
 164      number of cfg nodes with -fprofile-generate and -fprofile-use */
 165   int pid;
 166
 167   /* Set when function must be output - it is externally visible
 168      or its address is taken.  */
 169   unsigned needed : 1;
 170   /* Set when decl is an abstract function pointed to by the
 171      ABSTRACT_DECL_ORIGIN of a reachable function.  */
 172   unsigned abstract_and_needed : 1;
 173   /* Set when function is reachable by call from other function
 174      that is either reachable or needed.  */
 175   unsigned reachable : 1;
 176   /* Set once the function is lowered (i.e. its CFG is built).  */
 177   unsigned lowered : 1;
 178   /* Set once the function has been instantiated and its callee
 179      lists created.  */
 180   unsigned analyzed : 1;
 181   /* Set when function is scheduled to be processed by local passes.  */
 182   unsigned process : 1;
 183   /* Set for aliases once they got through assemble_alias.  */
 184   unsigned alias : 1;
 185
 186   /* In non-unit-at-a-time mode the function body of inline candidates is saved
 187      into clone before compiling so the function in original form can be
 188      inlined later.  This pointer points to the clone.  */
 189   tree inline_decl;
 190 };
 191
 192 typedef struct cgraph_node *cgraph_node_ptr;
 193
 194 DEF_VEC_P(cgraph_node_ptr);
 195 DEF_VEC_ALLOC_P(cgraph_node_ptr,heap);
 196 DEF_VEC_ALLOC_P(cgraph_node_ptr,gc);
 197
 198 /* A cgraph node set is a collection of cgraph nodes.  A cgraph node
 199    can appear in multiple sets.  */
 200 struct cgraph_node_set_def GTY(())
 201 {
 202   htab_t GTY((param_is (struct cgraph_node_set_element_def))) hashtab;
 203   VEC(cgraph_node_ptr, gc) *nodes;
 204   PTR GTY ((skip)) aux;
 205 };
 206
 207 typedef struct cgraph_node_set_def *cgraph_node_set;
 208
 209 DEF_VEC_P(cgraph_node_set);
 210 DEF_VEC_ALLOC_P(cgraph_node_set,gc);
 211 DEF_VEC_ALLOC_P(cgraph_node_set,heap);
 212
 213 /* A cgraph node set element contains an index in the vector of nodes in
 214    the set.  */
 215 struct cgraph_node_set_element_def GTY(())
 216 {
 217   struct cgraph_node *node;
 218   HOST_WIDE_INT index;
 219 };
 220
 221 typedef struct cgraph_node_set_element_def *cgraph_node_set_element;
 222 typedef const struct cgraph_node_set_element_def *const_cgraph_node_set_element;
 223
 224 /* Iterator structure for cgraph node sets.  */
 225 typedef struct
 226 {
 227   cgraph_node_set set;
 228   unsigned index;
 229 } cgraph_node_set_iterator;
 230
 231 #define DEFCIFCODE(code, string)        CIF_ ## code,
 232 /* Reasons for inlining failures.  */
 233 typedef enum {
 234 #include "cif-code.def"
 235   CIF_N_REASONS
 236 } cgraph_inline_failed_t;
 237
 238 struct cgraph_edge GTY((chain_next ("%h.next_caller"), chain_prev ("%h.prev_caller")))
 239 {
 240   struct cgraph_node *caller;
 241   struct cgraph_node *callee;
 242   struct cgraph_edge *prev_caller;
 243   struct cgraph_edge *next_caller;
 244   struct cgraph_edge *prev_callee;
 245   struct cgraph_edge *next_callee;
 246   gimple call_stmt;
 247   PTR GTY ((skip (""))) aux;
 248   /* When equal to CIF_OK, inline this call.  Otherwise, points to the
 249      explanation why function was not inlined.  */
 250   cgraph_inline_failed_t inline_failed;
 251   /* Expected number of executions: calculated in profile.c.  */
 252   gcov_type count;
 253   /* Expected frequency of executions within the function.
 254      When set to CGRAPH_FREQ_BASE, the edge is expected to be called once
 255      per function call.  The range is 0 to CGRAPH_FREQ_MAX.  */
 256   int frequency;
 257   /* Depth of loop nest, 1 means no loop nest.  */
 258   unsigned int loop_nest : 30;
 259   /* Whether this edge describes a call that was originally indirect.  */
 260   unsigned int indirect_call : 1;
 261   /* Can this call throw externally?  */
 262   unsigned int can_throw_external : 1;
 263   /* Unique id of the edge.  */
 264   int uid;
 265 };
 266
 267 #define CGRAPH_FREQ_BASE 1000
 268 #define CGRAPH_FREQ_MAX 100000
 269
 270 typedef struct cgraph_edge *cgraph_edge_p;
 271
 272 DEF_VEC_P(cgraph_edge_p);
 273 DEF_VEC_ALLOC_P(cgraph_edge_p,heap);
 274
 275 /* The varpool data structure.
 276    Each static variable decl has assigned varpool_node.  */
 277
 278 struct varpool_node GTY((chain_next ("%h.next")))
 279 {
 280   tree decl;
 281   /* Pointer to the next function in varpool_nodes.  */
 282   struct varpool_node *next;
 283   /* Pointer to the next function in varpool_nodes_queue.  */
 284   struct varpool_node *next_needed;
 285   /* Ordering of all cgraph nodes.  */
 286   int order;
 287
 288   /* Set when function must be output - it is externally visible
 289      or its address is taken.  */
 290   unsigned needed : 1;
 291   /* Needed variables might become dead by optimization.  This flag
 292      forces the variable to be output even if it appears dead otherwise.  */
 293   unsigned force_output : 1;
 294   /* Set once the variable has been instantiated and its callee
 295      lists created.  */
 296   unsigned analyzed : 1;
 297   /* Set once it has been finalized so we consider it to be output.  */
 298   unsigned finalized : 1;
 299   /* Set when variable is scheduled to be assembled.  */
 300   unsigned output : 1;
 301   /* Set when function is visible by other units.  */
 302   unsigned externally_visible : 1;
 303   /* Set for aliases once they got through assemble_alias.  */
 304   unsigned alias : 1;
 305 };
 306
 307 /* Every top level asm statement is put into a cgraph_asm_node.  */
 308
 309 struct cgraph_asm_node GTY(())
 310 {
 311   /* Next asm node.  */
 312   struct cgraph_asm_node *next;
 313   /* String for this asm node.  */
 314   tree asm_str;
 315   /* Ordering of all cgraph nodes.  */
 316   int order;
 317 };
 318
 319 extern GTY(()) struct cgraph_node *cgraph_nodes;
 320 extern GTY(()) int cgraph_n_nodes;
 321 extern GTY(()) int cgraph_max_uid;
 322 extern GTY(()) int cgraph_edge_max_uid;
 323 extern GTY(()) int cgraph_max_pid;
 324 extern bool cgraph_global_info_ready;
 325 enum cgraph_state
 326 {
 327   /* Callgraph is being constructed.  It is safe to add new functions.  */
 328   CGRAPH_STATE_CONSTRUCTION,
 329   /* Callgraph is built and IPA passes are being run.  */
 330   CGRAPH_STATE_IPA,
 331   /* Callgraph is built and all functions are transformed to SSA form.  */
 332   CGRAPH_STATE_IPA_SSA,
 333   /* Functions are now ordered and being passed to RTL expanders.  */
 334   CGRAPH_STATE_EXPANSION,
 335   /* All cgraph expansion is done.  */
 336   CGRAPH_STATE_FINISHED
 337 };
 338 extern enum cgraph_state cgraph_state;
 339 extern bool cgraph_function_flags_ready;
 340 extern GTY(()) struct cgraph_node *cgraph_nodes_queue;
 341 extern GTY(()) struct cgraph_node *cgraph_new_nodes;
 342
 343 extern GTY(()) struct cgraph_asm_node *cgraph_asm_nodes;
 344 extern GTY(()) int cgraph_order;
 345
 346 /* In cgraph.c  */
 347 void dump_cgraph (FILE *);
 348 void debug_cgraph (void);
 349 void dump_cgraph_node (FILE *, struct cgraph_node *);
 350 void debug_cgraph_node (struct cgraph_node *);
 351 void cgraph_insert_node_to_hashtable (struct cgraph_node *node);
 352 void cgraph_remove_edge (struct cgraph_edge *);
 353 void cgraph_remove_node (struct cgraph_node *);
 354 void cgraph_release_function_body (struct cgraph_node *);
 355 void cgraph_node_remove_callees (struct cgraph_node *node);
 356 struct cgraph_edge *cgraph_create_edge (struct cgraph_node *,
 357                                         struct cgraph_node *,
 358                                         gimple, gcov_type, int, int);
 359 struct cgraph_node *cgraph_node (tree);
 360 struct cgraph_node *cgraph_node_for_asm (tree asmname);
 361 struct cgraph_edge *cgraph_edge (struct cgraph_node *, gimple);
 362 void cgraph_set_call_stmt (struct cgraph_edge *, gimple);
 363 void cgraph_update_edges_for_call_stmt (gimple, gimple);
 364 struct cgraph_local_info *cgraph_local_info (tree);
 365 struct cgraph_global_info *cgraph_global_info (tree);
 366 struct cgraph_rtl_info *cgraph_rtl_info (tree);
 367 const char * cgraph_node_name (struct cgraph_node *);
 368 struct cgraph_edge * cgraph_clone_edge (struct cgraph_edge *,
 369                                         struct cgraph_node *,
 370                                         gimple, gcov_type, int, int, bool);
 371 struct cgraph_node * cgraph_clone_node (struct cgraph_node *, gcov_type, int,
 372                                         int, bool);
 373
 374 void cgraph_redirect_edge_callee (struct cgraph_edge *, struct cgraph_node *);
 375
 376 struct cgraph_asm_node *cgraph_add_asm_node (tree);
 377
 378 bool cgraph_function_possibly_inlined_p (tree);
 379 void cgraph_unnest_node (struct cgraph_node *);
 380
 381 enum availability cgraph_function_body_availability (struct cgraph_node *);
 382 void cgraph_add_new_function (tree, bool);
 383 const char* cgraph_inline_failed_string (cgraph_inline_failed_t);
 384
 385 /* In cgraphunit.c  */
 386 void cgraph_finalize_function (tree, bool);
 387 void cgraph_mark_if_needed (tree);
 388 void cgraph_finalize_compilation_unit (void);
 389 void cgraph_optimize (void);
 390 void cgraph_mark_needed_node (struct cgraph_node *);
 391 void cgraph_mark_reachable_node (struct cgraph_node *);
 392 bool cgraph_inline_p (struct cgraph_edge *, cgraph_inline_failed_t *reason);
 393 bool cgraph_preserve_function_body_p (tree);
 394 void verify_cgraph (void);
 395 void verify_cgraph_node (struct cgraph_node *);
 396 void cgraph_build_static_cdtor (char which, tree body, int priority);
 397 void cgraph_reset_static_var_maps (void);
 398 void init_cgraph (void);
 399 struct cgraph_node *cgraph_function_versioning (struct cgraph_node *,
 400                                                 VEC(cgraph_edge_p,heap)*,
 401                                                 varray_type,
 402                                                 bitmap);
 403 void cgraph_analyze_function (struct cgraph_node *);
 404 struct cgraph_node *save_inline_function_body (struct cgraph_node *);
 405 void record_references_in_initializer (tree);
 406 bool cgraph_process_new_functions (void);
 407
 408 typedef void (*cgraph_edge_hook)(struct cgraph_edge *, void *);
 409 typedef void (*cgraph_node_hook)(struct cgraph_node *, void *);
 410 typedef void (*cgraph_2edge_hook)(struct cgraph_edge *, struct cgraph_edge *,
 411                                   void *);
 412 typedef void (*cgraph_2node_hook)(struct cgraph_node *, struct cgraph_node *,
 413                                   void *);
 414 struct cgraph_edge_hook_list;
 415 struct cgraph_node_hook_list;
 416 struct cgraph_2edge_hook_list;
 417 struct cgraph_2node_hook_list;
 418 struct cgraph_edge_hook_list *cgraph_add_edge_removal_hook (cgraph_edge_hook, void *);
 419 void cgraph_remove_edge_removal_hook (struct cgraph_edge_hook_list *);
 420 struct cgraph_node_hook_list *cgraph_add_node_removal_hook (cgraph_node_hook,
 421                                                             void *);
 422 void cgraph_remove_node_removal_hook (struct cgraph_node_hook_list *);
 423 struct cgraph_node_hook_list *cgraph_add_function_insertion_hook (cgraph_node_hook,
 424                                                                   void *);
 425 void cgraph_remove_function_insertion_hook (struct cgraph_node_hook_list *);
 426 void cgraph_call_function_insertion_hooks (struct cgraph_node *node);
 427 struct cgraph_2edge_hook_list *cgraph_add_edge_duplication_hook (cgraph_2edge_hook, void *);
 428 void cgraph_remove_edge_duplication_hook (struct cgraph_2edge_hook_list *);
 429 struct cgraph_2node_hook_list *cgraph_add_node_duplication_hook (cgraph_2node_hook, void *);
 430 void cgraph_remove_node_duplication_hook (struct cgraph_2node_hook_list *);
 431
 432 /* In cgraphbuild.c  */
 433 unsigned int rebuild_cgraph_edges (void);
 434 int compute_call_stmt_bb_frequency (basic_block bb);
 435
 436 /* In ipa.c  */
 437 bool cgraph_remove_unreachable_nodes (bool, FILE *);
 438 int cgraph_postorder (struct cgraph_node **);
 439 cgraph_node_set cgraph_node_set_new (void);
 440 cgraph_node_set_iterator cgraph_node_set_find (cgraph_node_set,
 441                                                struct cgraph_node *);
 442 void cgraph_node_set_add (cgraph_node_set, struct cgraph_node *);
 443 void cgraph_node_set_remove (cgraph_node_set, struct cgraph_node *);
 444 void dump_cgraph_node_set (FILE *, cgraph_node_set);
 445 void debug_cgraph_node_set (cgraph_node_set);
 446
 447
 448 /* In predict.c  */
 449 bool cgraph_maybe_hot_edge_p (struct cgraph_edge *e);
 450
 451 /* In varpool.c  */
 452 extern GTY(()) struct varpool_node *varpool_nodes_queue;
 453 extern GTY(()) struct varpool_node *varpool_nodes;
 454
 455 struct varpool_node *varpool_node (tree);
 456 struct varpool_node *varpool_node_for_asm (tree asmname);
 457 void varpool_mark_needed_node (struct varpool_node *);
 458 void debug_varpool (void);
 459 void dump_varpool (FILE *);
 460 void dump_varpool_node (FILE *, struct varpool_node *);
 461
 462 void varpool_finalize_decl (tree);
 463 bool decide_is_variable_needed (struct varpool_node *, tree);
 464 enum availability cgraph_variable_initializer_availability (struct varpool_node *);
 465
 466 bool varpool_assemble_pending_decls (void);
 467 bool varpool_assemble_decl (struct varpool_node *node);
 468 bool varpool_analyze_pending_decls (void);
 469 void varpool_remove_unreferenced_decls (void);
 470 void varpool_empty_needed_queue (void);
 471
 472 /* Walk all reachable static variables.  */
 473 #define FOR_EACH_STATIC_VARIABLE(node) \
 474    for ((node) = varpool_nodes_queue; (node); (node) = (node)->next_needed)
 475
 476 /* Return first reachable static variable with initializer.  */
 477 static inline struct varpool_node *
 478 varpool_first_static_initializer (void)
 479 {
 480   struct varpool_node *node;
 481   for (node = varpool_nodes_queue; node; node = node->next_needed)
 482     {
 483       gcc_assert (TREE_CODE (node->decl) == VAR_DECL);
 484       if (DECL_INITIAL (node->decl))
 485         return node;
 486     }
 487   return NULL;
 488 }
 489
 490 /* Return next reachable static variable with initializer after NODE.  */
 491 static inline struct varpool_node *
 492 varpool_next_static_initializer (struct varpool_node *node)
 493 {
 494   for (node = node->next_needed; node; node = node->next_needed)
 495     {
 496       gcc_assert (TREE_CODE (node->decl) == VAR_DECL);
 497       if (DECL_INITIAL (node->decl))
 498         return node;
 499     }
 500   return NULL;
 501 }
 502
 503 /* Walk all static variables with initializer set.  */
 504 #define FOR_EACH_STATIC_INITIALIZER(node) \
 505    for ((node) = varpool_first_static_initializer (); (node); \
 506         (node) = varpool_next_static_initializer (node))
 507
 508 /* In ipa-inline.c  */
 509 void cgraph_clone_inlined_nodes (struct cgraph_edge *, bool, bool);
 510 unsigned int compute_inline_parameters (struct cgraph_node *);
 511
 512
 513 /* Create a new static variable of type TYPE.  */
 514 tree add_new_static_var (tree type);
 515
 516
 517 /* Return true if iterator CSI points to nothing.  */
 518 static inline bool
 519 csi_end_p (cgraph_node_set_iterator csi)
 520 {
 521   return csi.index >= VEC_length (cgraph_node_ptr, csi.set->nodes);
 522 }
 523
 524 /* Advance iterator CSI.  */
 525 static inline void
 526 csi_next (cgraph_node_set_iterator *csi)
 527 {
 528   csi->index++;
 529 }
 530
 531 /* Return the node pointed to by CSI.  */
 532 static inline struct cgraph_node *
 533 csi_node (cgraph_node_set_iterator csi)
 534 {
 535   return VEC_index (cgraph_node_ptr, csi.set->nodes, csi.index);
 536 }
 537
 538 /* Return an iterator to the first node in SET.  */
 539 static inline cgraph_node_set_iterator
 540 csi_start (cgraph_node_set set)
 541 {
 542   cgraph_node_set_iterator csi;
 543
 544   csi.set = set;
 545   csi.index = 0;
 546   return csi;
 547 }
 548
 549 /* Return true if SET contains NODE.  */
 550 static inline bool
 551 cgraph_node_in_set_p (struct cgraph_node *node, cgraph_node_set set)
 552 {
 553   cgraph_node_set_iterator csi;
 554   csi = cgraph_node_set_find (set, node);
 555   return !csi_end_p (csi);
 556 }
 557
 558 /* Return number of nodes in SET.  */
 559 static inline size_t
 560 cgraph_node_set_size (cgraph_node_set set)
 561 {
 562   return htab_elements (set->hashtab);
 563 }
 564
 565
 566 #endif  /* GCC_CGRAPH_H  */