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-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 inlined into.  */
 104   struct cgraph_node *inlined_to;
 105
 106   /* Estimated size of the function after inlining.  */
 107   int insns;
 108
 109   /* Estimated growth after inlining.  INT_MIN if not computed.  */
 110   int estimated_growth;
 111
 112   /* Set iff the function has been inlined at least once.  */
 113   bool inlined;
 114 };
 115
 116 /* Information about the function that is propagated by the RTL backend.
 117    Available only for functions that has been already assembled.  */
 118
 119 struct cgraph_rtl_info GTY(())
 120 {
 121    unsigned int preferred_incoming_stack_boundary;
 122 };
 123
 124 /* The cgraph data structure.
 125    Each function decl has assigned cgraph_node listing callees and callers.  */
 126
 127 struct cgraph_node GTY((chain_next ("%h.next"), chain_prev ("%h.previous")))
 128 {
 129   tree decl;
 130   struct cgraph_edge *callees;
 131   struct cgraph_edge *callers;
 132   struct cgraph_node *next;
 133   struct cgraph_node *previous;
 134   /* For nested functions points to function the node is nested in.  */
 135   struct cgraph_node *origin;
 136   /* Points to first nested function, if any.  */
 137   struct cgraph_node *nested;
 138   /* Pointer to the next function with same origin, if any.  */
 139   struct cgraph_node *next_nested;
 140   /* Pointer to the next function in cgraph_nodes_queue.  */
 141   struct cgraph_node *next_needed;
 142   /* Pointer to the next clone.  */
 143   struct cgraph_node *next_clone;
 144   struct cgraph_node *prev_clone;
 145   /* Pointer to a single unique cgraph node for this function.  If the
 146      function is to be output, this is the copy that will survive.  */
 147   struct cgraph_node *master_clone;
 148   /* For functions with many calls sites it holds map from call expression
 149      to the edge to speed up cgraph_edge function.  */
 150   htab_t GTY((param_is (struct cgraph_edge))) call_site_hash;
 151
 152   PTR GTY ((skip)) aux;
 153
 154   struct cgraph_local_info local;
 155   struct cgraph_global_info global;
 156   struct cgraph_rtl_info rtl;
 157
 158   /* Expected number of executions: calculated in profile.c.  */
 159   gcov_type count;
 160   /* Unique id of the node.  */
 161   int uid;
 162   /* Ordering of all cgraph nodes.  */
 163   int order;
 164
 165   /* Set when function must be output - it is externally visible
 166      or its address is taken.  */
 167   unsigned needed : 1;
 168   /* Set when function is reachable by call from other function
 169      that is either reachable or needed.  */
 170   unsigned reachable : 1;
 171   /* Set once the function is lowered (i.e. its CFG is built).  */
 172   unsigned lowered : 1;
 173   /* Set once the function has been instantiated and its callee
 174      lists created.  */
 175   unsigned analyzed : 1;
 176   /* Set when function is scheduled to be assembled.  */
 177   unsigned output : 1;
 178   /* Set for aliases once they got through assemble_alias.  */
 179   unsigned alias : 1;
 180
 181   /* In non-unit-at-a-time mode the function body of inline candidates is saved
 182      into clone before compiling so the function in original form can be
 183      inlined later.  This pointer points to the clone.  */
 184   tree inline_decl;
 185
 186   /* unique id for profiling. pid is not suitable because of different
 187      number of cfg nodes with -fprofile-generate and -fprofile-use */
 188   int pid;
 189
 190   /* Call unsaved hard registers really used by the corresponding
 191      function (including ones used by functions called by the
 192      function).  */
 193   HARD_REG_SET function_used_regs;
 194 };
 195
 196 struct cgraph_edge GTY((chain_next ("%h.next_caller"), chain_prev ("%h.prev_caller")))
 197 {
 198   struct cgraph_node *caller;
 199   struct cgraph_node *callee;
 200   struct cgraph_edge *prev_caller;
 201   struct cgraph_edge *next_caller;
 202   struct cgraph_edge *prev_callee;
 203   struct cgraph_edge *next_callee;
 204   tree call_stmt;
 205   PTR GTY ((skip (""))) aux;
 206   /* When NULL, inline this call.  When non-NULL, points to the explanation
 207      why function was not inlined.  */
 208   const char *inline_failed;
 209   /* Expected number of executions: calculated in profile.c.  */
 210   gcov_type count;
 211   /* Expected frequency of executions within the function.
 212      When set to CGRAPH_FREQ_BASE, the edge is expected to be called once
 213      per function call.  The range is 0 to CGRAPH_FREQ_MAX.  */
 214   int frequency;
 215   /* Depth of loop nest, 1 means no loop nest.  */
 216   int loop_nest;
 217 };
 218
 219 #define CGRAPH_FREQ_BASE 1000
 220 #define CGRAPH_FREQ_MAX 100000
 221
 222 typedef struct cgraph_edge *cgraph_edge_p;
 223
 224 DEF_VEC_P(cgraph_edge_p);
 225 DEF_VEC_ALLOC_P(cgraph_edge_p,heap);
 226
 227 /* The varpool data structure.
 228    Each static variable decl has assigned varpool_node.  */
 229
 230 struct varpool_node GTY(())
 231 {
 232   tree decl;
 233   /* Pointer to the next function in varpool_nodes.  */
 234   struct varpool_node *next;
 235   /* Pointer to the next function in varpool_nodes_queue.  */
 236   struct varpool_node *next_needed;
 237   /* Ordering of all cgraph nodes.  */
 238   int order;
 239
 240   /* Set when function must be output - it is externally visible
 241      or its address is taken.  */
 242   unsigned needed : 1;
 243   /* Needed variables might become dead by optimization.  This flag
 244      forces the variable to be output even if it appears dead otherwise.  */
 245   unsigned force_output : 1;
 246   /* Set once the variable has been instantiated and its callee
 247      lists created.  */
 248   unsigned analyzed : 1;
 249   /* Set once it has been finalized so we consider it to be output.  */
 250   unsigned finalized : 1;
 251   /* Set when variable is scheduled to be assembled.  */
 252   unsigned output : 1;
 253   /* Set when function is visible by other units.  */
 254   unsigned externally_visible : 1;
 255   /* Set for aliases once they got through assemble_alias.  */
 256   unsigned alias : 1;
 257 };
 258
 259 /* Every top level asm statement is put into a cgraph_asm_node.  */
 260
 261 struct cgraph_asm_node GTY(())
 262 {
 263   /* Next asm node.  */
 264   struct cgraph_asm_node *next;
 265   /* String for this asm node.  */
 266   tree asm_str;
 267   /* Ordering of all cgraph nodes.  */
 268   int order;
 269 };
 270
 271 extern GTY(()) struct cgraph_node *cgraph_nodes;
 272 extern GTY(()) int cgraph_n_nodes;
 273 extern GTY(()) int cgraph_max_uid;
 274 extern GTY(()) int cgraph_max_pid;
 275 extern bool cgraph_global_info_ready;
 276 enum cgraph_state
 277 {
 278   /* Callgraph is being constructed.  It is safe to add new functions.  */
 279   CGRAPH_STATE_CONSTRUCTION,
 280   /* Callgraph is built and IPA passes are being run.  */
 281   CGRAPH_STATE_IPA,
 282   /* Callgraph is built and all functions are transformed to SSA form.  */
 283   CGRAPH_STATE_IPA_SSA,
 284   /* Functions are now ordered and being passed to RTL expanders.  */
 285   CGRAPH_STATE_EXPANSION,
 286   /* All cgraph expansion is done.  */
 287   CGRAPH_STATE_FINISHED
 288 };
 289 extern enum cgraph_state cgraph_state;
 290 extern bool cgraph_function_flags_ready;
 291 extern GTY(()) struct cgraph_node *cgraph_nodes_queue;
 292 extern GTY(()) struct cgraph_node *cgraph_new_nodes;
 293
 294 extern GTY(()) struct cgraph_asm_node *cgraph_asm_nodes;
 295 extern GTY(()) int cgraph_order;
 296
 297 /* In cgraph.c  */
 298 void dump_cgraph (FILE *);
 299 void debug_cgraph (void);
 300 void dump_cgraph_node (FILE *, struct cgraph_node *);
 301 void debug_cgraph_node (struct cgraph_node *);
 302 void cgraph_insert_node_to_hashtable (struct cgraph_node *node);
 303 void cgraph_remove_edge (struct cgraph_edge *);
 304 void cgraph_remove_node (struct cgraph_node *);
 305 void cgraph_release_function_body (struct cgraph_node *);
 306 void cgraph_node_remove_callees (struct cgraph_node *node);
 307 struct cgraph_edge *cgraph_create_edge (struct cgraph_node *,
 308                                         struct cgraph_node *,
 309                                         tree, gcov_type, int, int);
 310 struct cgraph_node *cgraph_node (tree);
 311 struct cgraph_node *cgraph_node_for_asm (tree asmname);
 312 struct cgraph_edge *cgraph_edge (struct cgraph_node *, tree);
 313 void cgraph_set_call_stmt (struct cgraph_edge *, tree);
 314 void cgraph_update_edges_for_call_stmt (tree, tree, tree);
 315 struct cgraph_local_info *cgraph_local_info (tree);
 316 struct cgraph_global_info *cgraph_global_info (tree);
 317 struct cgraph_rtl_info *cgraph_rtl_info (tree);
 318 const char * cgraph_node_name (struct cgraph_node *);
 319 struct cgraph_edge * cgraph_clone_edge (struct cgraph_edge *,
 320                                         struct cgraph_node *,
 321                                         tree, gcov_type, int, int, bool);
 322 struct cgraph_node * cgraph_clone_node (struct cgraph_node *, gcov_type, int,
 323                                         int, bool);
 324
 325 void cgraph_redirect_edge_callee (struct cgraph_edge *, struct cgraph_node *);
 326
 327 struct cgraph_asm_node *cgraph_add_asm_node (tree);
 328
 329 bool cgraph_function_possibly_inlined_p (tree);
 330 void cgraph_unnest_node (struct cgraph_node *);
 331
 332 enum availability cgraph_function_body_availability (struct cgraph_node *);
 333 bool cgraph_is_master_clone (struct cgraph_node *);
 334 struct cgraph_node *cgraph_master_clone (struct cgraph_node *);
 335 void cgraph_add_new_function (tree, bool);
 336
 337 /* In cgraphunit.c  */
 338 void cgraph_finalize_function (tree, bool);
 339 void cgraph_finalize_compilation_unit (void);
 340 void cgraph_optimize (void);
 341 void cgraph_mark_needed_node (struct cgraph_node *);
 342 void cgraph_mark_reachable_node (struct cgraph_node *);
 343 bool cgraph_inline_p (struct cgraph_edge *, const char **reason);
 344 bool cgraph_preserve_function_body_p (tree);
 345 void verify_cgraph (void);
 346 void verify_cgraph_node (struct cgraph_node *);
 347 void cgraph_build_static_cdtor (char which, tree body, int priority);
 348 void cgraph_reset_static_var_maps (void);
 349 void init_cgraph (void);
 350 struct cgraph_node *cgraph_function_versioning (struct cgraph_node *,
 351                                                 VEC(cgraph_edge_p,heap)*,
 352                                                 varray_type);
 353 void cgraph_analyze_function (struct cgraph_node *);
 354 struct cgraph_node *save_inline_function_body (struct cgraph_node *);
 355 void record_references_in_initializer (tree);
 356 bool cgraph_process_new_functions (void);
 357
 358 /* In cgraphbuild.c  */
 359 unsigned int rebuild_cgraph_edges (void);
 360
 361 /* In ipa.c  */
 362 bool cgraph_remove_unreachable_nodes (bool, FILE *);
 363 int cgraph_postorder (struct cgraph_node **);
 364
 365 /* In varpool.c  */
 366
 367 extern GTY(()) struct varpool_node *varpool_nodes_queue;
 368 extern GTY(()) struct varpool_node *varpool_nodes;
 369
 370 struct varpool_node *varpool_node (tree);
 371 struct varpool_node *varpool_node_for_asm (tree asmname);
 372 void varpool_mark_needed_node (struct varpool_node *);
 373 void dump_varpool (FILE *);
 374 void dump_varpool_node (FILE *, struct varpool_node *);
 375
 376 void varpool_finalize_decl (tree);
 377 bool decide_is_variable_needed (struct varpool_node *, tree);
 378 enum availability cgraph_variable_initializer_availability (struct varpool_node *);
 379
 380 bool varpool_assemble_pending_decls (void);
 381 bool varpool_assemble_decl (struct varpool_node *node);
 382 bool varpool_analyze_pending_decls (void);
 383 void varpool_output_debug_info (void);
 384 void varpool_remove_unreferenced_decls (void);
 385
 386 /* Walk all reachable static variables.  */
 387 #define FOR_EACH_STATIC_VARIABLE(node) \
 388    for ((node) = varpool_nodes_queue; (node); (node) = (node)->next_needed)
 389
 390 /* Return first reachable static variable with initializer.  */
 391 static inline struct varpool_node *
 392 varpool_first_static_initializer (void)
 393 {
 394   struct varpool_node *node;
 395   for (node = varpool_nodes_queue; node; node = node->next_needed)
 396     {
 397       gcc_assert (TREE_CODE (node->decl) == VAR_DECL);
 398       if (DECL_INITIAL (node->decl))
 399         return node;
 400     }
 401   return NULL;
 402 }
 403
 404 /* Return next reachable static variable with initializer after NODE.  */
 405 static inline struct varpool_node *
 406 varpool_next_static_initializer (struct varpool_node *node)
 407 {
 408   for (node = node->next_needed; node; node = node->next_needed)
 409     {
 410       gcc_assert (TREE_CODE (node->decl) == VAR_DECL);
 411       if (DECL_INITIAL (node->decl))
 412         return node;
 413     }
 414   return NULL;
 415 }
 416
 417 /* Walk all static variables with initializer set.  */
 418 #define FOR_EACH_STATIC_INITIALIZER(node) \
 419    for ((node) = varpool_first_static_initializer (); (node); \
 420         (node) = varpool_next_static_initializer (node))
 421
 422 /* In ipa-inline.c  */
 423 void cgraph_clone_inlined_nodes (struct cgraph_edge *, bool, bool);
 424 void cgraph_mark_inline_edge (struct cgraph_edge *, bool);
 425 bool cgraph_default_inline_p (struct cgraph_node *, const char **);
 426 unsigned int compute_inline_parameters (struct cgraph_node *);
 427
 428
 429 /* Create a new static variable of type TYPE.  */
 430 tree add_new_static_var (tree type);
 431
 432 #endif  /* GCC_CGRAPH_H  */