1/* Garbage collection for the GNU compiler. 2 Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 3 Free Software Foundation, Inc. 4 5This file is part of GCC. 6 7GCC is free software; you can redistribute it and/or modify it under 8the terms of the GNU General Public License as published by the Free 9Software Foundation; either version 2, or (at your option) any later 10version. 11 12GCC is distributed in the hope that it will be useful, but WITHOUT ANY 13WARRANTY; without even the implied warranty of MERCHANTABILITY or 14FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15for more details. 16 17You should have received a copy of the GNU General Public License 18along with GCC; see the file COPYING. If not, write to the Free 19Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 2002110-1301, USA. */ 21 22#ifndef GCC_GGC_H 23#define GCC_GGC_H 24#include "statistics.h" 25 26/* Symbols are marked with `ggc' for `gcc gc' so as not to interfere with 27 an external gc library that might be linked in. */ 28 29/* Constants for general use. */ 30extern const char empty_string[]; /* empty string */ 31extern const char digit_vector[]; /* "0" .. "9" */ 32#define digit_string(d) (digit_vector + ((d) * 2)) 33 34/* Internal functions and data structures used by the GTY 35 machinery. */ 36 37/* The first parameter is a pointer to a pointer, the second a cookie. */ 38typedef void (*gt_pointer_operator) (void *, void *); 39 40#include "gtype-desc.h" 41 42/* One of these applies its third parameter (with cookie in the fourth 43 parameter) to each pointer in the object pointed to by the first 44 parameter, using the second parameter. */ 45typedef void (*gt_note_pointers) (void *, void *, gt_pointer_operator, 46 void *); 47 48/* One of these is called before objects are re-ordered in memory. 49 The first parameter is the original object, the second is the 50 subobject that has had its pointers reordered, the third parameter 51 can compute the new values of a pointer when given the cookie in 52 the fourth parameter. */ 53typedef void (*gt_handle_reorder) (void *, void *, gt_pointer_operator, 54 void *); 55 56/* Used by the gt_pch_n_* routines. Register an object in the hash table. */ 57extern int gt_pch_note_object (void *, void *, gt_note_pointers, 58 enum gt_types_enum); 59 60/* Used by the gt_pch_n_* routines. Register that an object has a reorder 61 function. */ 62extern void gt_pch_note_reorder (void *, void *, gt_handle_reorder); 63 64/* Mark the object in the first parameter and anything it points to. */ 65typedef void (*gt_pointer_walker) (void *); 66 67/* Structures for the easy way to mark roots. 68 In an array, terminated by having base == NULL. */ 69struct ggc_root_tab { 70 void *base; 71 size_t nelt; 72 size_t stride; 73 gt_pointer_walker cb; 74 gt_pointer_walker pchw; 75}; 76#define LAST_GGC_ROOT_TAB { NULL, 0, 0, NULL, NULL } 77/* Pointers to arrays of ggc_root_tab, terminated by NULL. */ 78extern const struct ggc_root_tab * const gt_ggc_rtab[]; 79extern const struct ggc_root_tab * const gt_ggc_deletable_rtab[]; 80extern const struct ggc_root_tab * const gt_pch_cache_rtab[]; 81extern const struct ggc_root_tab * const gt_pch_scalar_rtab[]; 82 83/* Structure for hash table cache marking. */ 84struct htab; 85struct ggc_cache_tab { 86 struct htab * *base; 87 size_t nelt; 88 size_t stride; 89 gt_pointer_walker cb; 90 gt_pointer_walker pchw; 91 int (*marked_p) (const void *); 92}; 93#define LAST_GGC_CACHE_TAB { NULL, 0, 0, NULL, NULL, NULL } 94/* Pointers to arrays of ggc_cache_tab, terminated by NULL. */ 95extern const struct ggc_cache_tab * const gt_ggc_cache_rtab[]; 96 97/* If EXPR is not NULL and previously unmarked, mark it and evaluate 98 to true. Otherwise evaluate to false. */ 99#define ggc_test_and_set_mark(EXPR) \ 100 ((EXPR) != NULL && ((void *) (EXPR)) != (void *) 1 && ! ggc_set_mark (EXPR)) 101 102#define ggc_mark(EXPR) \ 103 do { \ 104 const void *const a__ = (EXPR); \ 105 if (a__ != NULL && a__ != (void *) 1) \ 106 ggc_set_mark (a__); \ 107 } while (0) 108 109/* Actually set the mark on a particular region of memory, but don't 110 follow pointers. This function is called by ggc_mark_*. It 111 returns zero if the object was not previously marked; nonzero if 112 the object was already marked, or if, for any other reason, 113 pointers in this data structure should not be traversed. */ 114extern int ggc_set_mark (const void *); 115 116/* Return 1 if P has been marked, zero otherwise. 117 P must have been allocated by the GC allocator; it mustn't point to 118 static objects, stack variables, or memory allocated with malloc. */ 119extern int ggc_marked_p (const void *); 120 121/* Mark the entries in the string pool. */ 122extern void ggc_mark_stringpool (void); 123 124/* Call ggc_set_mark on all the roots. */ 125 126extern void ggc_mark_roots (void); 127 128/* Save and restore the string pool entries for PCH. */ 129 130extern void gt_pch_save_stringpool (void); 131extern void gt_pch_fixup_stringpool (void); 132extern void gt_pch_restore_stringpool (void); 133 134/* PCH and GGC handling for strings, mostly trivial. */ 135 136extern void gt_pch_p_S (void *, void *, gt_pointer_operator, void *); 137extern void gt_pch_n_S (const void *); 138extern void gt_ggc_m_S (void *); 139 140/* Initialize the string pool. */ 141extern void init_stringpool (void); 142 143/* A GC implementation must provide these functions. They are internal 144 to the GC system. */ 145 146/* Forward declare the zone structure. Only ggc_zone implements this. */ 147struct alloc_zone; 148 149/* Initialize the garbage collector. */ 150extern void init_ggc (void); 151 152/* Start a new GGC zone. */ 153extern struct alloc_zone *new_ggc_zone (const char *); 154 155/* Free a complete GGC zone, destroying everything in it. */ 156extern void destroy_ggc_zone (struct alloc_zone *); 157 158struct ggc_pch_data; 159 160/* Return a new ggc_pch_data structure. */ 161extern struct ggc_pch_data *init_ggc_pch (void); 162 163/* The second parameter and third parameters give the address and size 164 of an object. Update the ggc_pch_data structure with as much of 165 that information as is necessary. The bool argument should be true 166 if the object is a string. */ 167extern void ggc_pch_count_object (struct ggc_pch_data *, void *, size_t, bool, 168 enum gt_types_enum); 169 170/* Return the total size of the data to be written to hold all 171 the objects previously passed to ggc_pch_count_object. */ 172extern size_t ggc_pch_total_size (struct ggc_pch_data *); 173 174/* The objects, when read, will most likely be at the address 175 in the second parameter. */ 176extern void ggc_pch_this_base (struct ggc_pch_data *, void *); 177 178/* Assuming that the objects really do end up at the address 179 passed to ggc_pch_this_base, return the address of this object. 180 The bool argument should be true if the object is a string. */ 181extern char *ggc_pch_alloc_object (struct ggc_pch_data *, void *, size_t, bool, 182 enum gt_types_enum); 183 184/* Write out any initial information required. */ 185extern void ggc_pch_prepare_write (struct ggc_pch_data *, FILE *); 186/* Write out this object, including any padding. The last argument should be 187 true if the object is a string. */ 188extern void ggc_pch_write_object (struct ggc_pch_data *, FILE *, void *, 189 void *, size_t, bool); 190/* All objects have been written, write out any final information 191 required. */ 192extern void ggc_pch_finish (struct ggc_pch_data *, FILE *); 193 194/* A PCH file has just been read in at the address specified second 195 parameter. Set up the GC implementation for the new objects. */ 196extern void ggc_pch_read (FILE *, void *); 197 198 199/* Allocation. */ 200 201/* When set, ggc_collect will do collection. */ 202extern bool ggc_force_collect; 203 204/* The internal primitive. */ 205extern void *ggc_alloc_stat (size_t MEM_STAT_DECL); 206#define ggc_alloc(s) ggc_alloc_stat (s MEM_STAT_INFO) 207/* Allocate an object of the specified type and size. */ 208extern void *ggc_alloc_typed_stat (enum gt_types_enum, size_t MEM_STAT_DECL); 209#define ggc_alloc_typed(s,z) ggc_alloc_typed_stat (s,z MEM_STAT_INFO) 210/* Like ggc_alloc, but allocates cleared memory. */ 211extern void *ggc_alloc_cleared_stat (size_t MEM_STAT_DECL); 212#define ggc_alloc_cleared(s) ggc_alloc_cleared_stat (s MEM_STAT_INFO) 213/* Resize a block. */ 214extern void *ggc_realloc_stat (void *, size_t MEM_STAT_DECL); 215#define ggc_realloc(s,z) ggc_realloc_stat (s,z MEM_STAT_INFO) 216/* Like ggc_alloc_cleared, but performs a multiplication. */ 217extern void *ggc_calloc (size_t, size_t); 218/* Free a block. To be used when known for certain it's not reachable. */ 219extern void ggc_free (void *); 220 221extern void ggc_record_overhead (size_t, size_t, void * MEM_STAT_DECL); 222extern void ggc_free_overhead (void *); 223extern void ggc_prune_overhead_list (void); 224 225extern void dump_ggc_loc_statistics (void); 226 227/* Type-safe, C++-friendly versions of ggc_alloc() and gcc_calloc(). */ 228#define GGC_NEW(T) ((T *) ggc_alloc (sizeof (T))) 229#define GGC_CNEW(T) ((T *) ggc_alloc_cleared (sizeof (T))) 230#define GGC_NEWVEC(T, N) ((T *) ggc_alloc ((N) * sizeof(T))) 231#define GGC_CNEWVEC(T, N) ((T *) ggc_alloc_cleared ((N) * sizeof(T))) 232#define GGC_NEWVAR(T, S) ((T *) ggc_alloc ((S))) 233#define GGC_CNEWVAR(T, S) ((T *) ggc_alloc_cleared ((S))) 234#define GGC_RESIZEVEC(T, P, N) ((T *) ggc_realloc ((P), (N) * sizeof (T))) 235 236#define ggc_alloc_rtvec(NELT) \ 237 ((rtvec) ggc_alloc_zone (sizeof (struct rtvec_def) + ((NELT) - 1) \ 238 * sizeof (rtx), &rtl_zone)) 239 240#define ggc_alloc_tree(LENGTH) ((tree) ggc_alloc_zone (LENGTH, &tree_zone)) 241 242#define htab_create_ggc(SIZE, HASH, EQ, DEL) \ 243 htab_create_alloc (SIZE, HASH, EQ, DEL, ggc_calloc, NULL) 244 245#define splay_tree_new_ggc(COMPARE) \ 246 splay_tree_new_with_allocator (COMPARE, NULL, NULL, \ 247 &ggc_splay_alloc, &ggc_splay_dont_free, \ 248 NULL) 249extern void *ggc_splay_alloc (int, void *); 250extern void ggc_splay_dont_free (void *, void *); 251 252/* Allocate a gc-able string, and fill it with LENGTH bytes from CONTENTS. 253 If LENGTH is -1, then CONTENTS is assumed to be a 254 null-terminated string and the memory sized accordingly. */ 255extern const char *ggc_alloc_string (const char *contents, int length); 256 257/* Make a copy of S, in GC-able memory. */ 258#define ggc_strdup(S) ggc_alloc_string((S), -1) 259 260/* Invoke the collector. Garbage collection occurs only when this 261 function is called, not during allocations. */ 262extern void ggc_collect (void); 263 264/* Return the number of bytes allocated at the indicated address. */ 265extern size_t ggc_get_size (const void *); 266 267/* Write out all GCed objects to F. */ 268extern void gt_pch_save (FILE *f); 269 270/* Read objects previously saved with gt_pch_save from F. */ 271extern void gt_pch_restore (FILE *f); 272 273/* Statistics. */ 274 275/* This structure contains the statistics common to all collectors. 276 Particular collectors can extend this structure. */ 277typedef struct ggc_statistics 278{ 279 /* At present, we don't really gather any interesting statistics. */ 280 int unused; 281} ggc_statistics; 282 283/* Used by the various collectors to gather and print statistics that 284 do not depend on the collector in use. */ 285extern void ggc_print_common_statistics (FILE *, ggc_statistics *); 286 287/* Print allocation statistics. */ 288extern void ggc_print_statistics (void); 289extern void stringpool_statistics (void); 290 291/* Heuristics. */ 292extern int ggc_min_expand_heuristic (void); 293extern int ggc_min_heapsize_heuristic (void); 294extern void init_ggc_heuristics (void); 295 296/* Zone collection. */ 297#if defined (GGC_ZONE) && !defined (GENERATOR_FILE) 298 299/* For regular rtl allocations. */ 300extern struct alloc_zone rtl_zone; 301/* For regular tree allocations. */ 302extern struct alloc_zone tree_zone; 303/* For IDENTIFIER_NODE allocations. */ 304extern struct alloc_zone tree_id_zone; 305 306/* Allocate an object into the specified allocation zone. */ 307extern void *ggc_alloc_zone_stat (size_t, struct alloc_zone * MEM_STAT_DECL); 308# define ggc_alloc_zone(s,z) ggc_alloc_zone_stat (s,z MEM_STAT_INFO) 309# define ggc_alloc_zone_pass_stat(s,z) ggc_alloc_zone_stat (s,z PASS_MEM_STAT) 310#else 311 312# define ggc_alloc_zone(s, z) ggc_alloc (s) 313# define ggc_alloc_zone_pass_stat(s, z) ggc_alloc_stat (s PASS_MEM_STAT) 314 315#endif 316 317#endif 318