| 1 | /* Copyright (C) 1995,1996 Free Software Foundation, Inc. |
| 2 | * |
| 3 | * This program is free software; you can redistribute it and/or modify |
| 4 | * it under the terms of the GNU General Public License as published by |
| 5 | * the Free Software Foundation; either version 2, or (at your option) |
| 6 | * any later version. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, |
| 9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 11 | * GNU General Public License for more details. |
| 12 | * |
| 13 | * You should have received a copy of the GNU General Public License |
| 14 | * along with this software; see the file COPYING. If not, write to |
| 15 | * the Free Software Foundation, Inc., 59 Temple Place, Suite 330, |
| 16 | * Boston, MA 02111-1307 USA |
| 17 | * |
| 18 | * As a special exception, the Free Software Foundation gives permission |
| 19 | * for additional uses of the text contained in its release of GUILE. |
| 20 | * |
| 21 | * The exception is that, if you link the GUILE library with other files |
| 22 | * to produce an executable, this does not by itself cause the |
| 23 | * resulting executable to be covered by the GNU General Public License. |
| 24 | * Your use of that executable is in no way restricted on account of |
| 25 | * linking the GUILE library code into it. |
| 26 | * |
| 27 | * This exception does not however invalidate any other reasons why |
| 28 | * the executable file might be covered by the GNU General Public License. |
| 29 | * |
| 30 | * This exception applies only to the code released by the |
| 31 | * Free Software Foundation under the name GUILE. If you copy |
| 32 | * code from other Free Software Foundation releases into a copy of |
| 33 | * GUILE, as the General Public License permits, the exception does |
| 34 | * not apply to the code that you add in this way. To avoid misleading |
| 35 | * anyone as to the status of such modified files, you must delete |
| 36 | * this exception notice from them. |
| 37 | * |
| 38 | * If you write modifications of your own for GUILE, it is your choice |
| 39 | * whether to permit this exception to apply to your modifications. |
| 40 | * If you do not wish that, delete this exception notice. */ |
| 41 | \f |
| 42 | #include <stdio.h> |
| 43 | #include "_scm.h" |
| 44 | #include "stime.h" |
| 45 | #include "stackchk.h" |
| 46 | #include "struct.h" |
| 47 | #include "genio.h" |
| 48 | #include "weaks.h" |
| 49 | #include "smob.h" |
| 50 | #include "unif.h" |
| 51 | #include "async.h" |
| 52 | |
| 53 | #include "gc.h" |
| 54 | |
| 55 | #ifdef HAVE_MALLOC_H |
| 56 | #include <malloc.h> |
| 57 | #endif |
| 58 | |
| 59 | #ifdef HAVE_UNISTD_H |
| 60 | #include <unistd.h> |
| 61 | #endif |
| 62 | |
| 63 | #ifdef __STDC__ |
| 64 | #include <stdarg.h> |
| 65 | #define var_start(x, y) va_start(x, y) |
| 66 | #else |
| 67 | #include <varargs.h> |
| 68 | #define var_start(x, y) va_start(x) |
| 69 | #endif |
| 70 | |
| 71 | \f |
| 72 | /* {heap tuning parameters} |
| 73 | * |
| 74 | * These are parameters for controlling memory allocation. The heap |
| 75 | * is the area out of which scm_cons, and object headers are allocated. |
| 76 | * |
| 77 | * Each heap cell is 8 bytes on a 32 bit machine and 16 bytes on a |
| 78 | * 64 bit machine. The units of the _SIZE parameters are bytes. |
| 79 | * Cons pairs and object headers occupy one heap cell. |
| 80 | * |
| 81 | * SCM_INIT_HEAP_SIZE is the initial size of heap. If this much heap is |
| 82 | * allocated initially the heap will grow by half its current size |
| 83 | * each subsequent time more heap is needed. |
| 84 | * |
| 85 | * If SCM_INIT_HEAP_SIZE heap cannot be allocated initially, SCM_HEAP_SEG_SIZE |
| 86 | * will be used, and the heap will grow by SCM_HEAP_SEG_SIZE when more |
| 87 | * heap is needed. SCM_HEAP_SEG_SIZE must fit into type scm_sizet. This code |
| 88 | * is in scm_init_storage() and alloc_some_heap() in sys.c |
| 89 | * |
| 90 | * If SCM_INIT_HEAP_SIZE can be allocated initially, the heap will grow by |
| 91 | * SCM_EXPHEAP(scm_heap_size) when more heap is needed. |
| 92 | * |
| 93 | * SCM_MIN_HEAP_SEG_SIZE is minimum size of heap to accept when more heap |
| 94 | * is needed. |
| 95 | * |
| 96 | * INIT_MALLOC_LIMIT is the initial amount of malloc usage which will |
| 97 | * trigger a GC. |
| 98 | * |
| 99 | * SCM_MTRIGGER_HYSTERESIS is the amount of malloc storage that must be |
| 100 | * reclaimed by a GC triggered by must_malloc. If less than this is |
| 101 | * reclaimed, the trigger threshold is raised. [I don't know what a |
| 102 | * good value is. I arbitrarily chose 1/10 of the INIT_MALLOC_LIMIT to |
| 103 | * work around a oscillation that caused almost constant GC.] |
| 104 | */ |
| 105 | |
| 106 | #define SCM_INIT_HEAP_SIZE (32768L*sizeof(scm_cell)) |
| 107 | #define SCM_MIN_HEAP_SEG_SIZE (2048L*sizeof(scm_cell)) |
| 108 | #ifdef _QC |
| 109 | # define SCM_HEAP_SEG_SIZE 32768L |
| 110 | #else |
| 111 | # ifdef sequent |
| 112 | # define SCM_HEAP_SEG_SIZE (7000L*sizeof(scm_cell)) |
| 113 | # else |
| 114 | # define SCM_HEAP_SEG_SIZE (16384L*sizeof(scm_cell)) |
| 115 | # endif |
| 116 | #endif |
| 117 | #define SCM_EXPHEAP(scm_heap_size) (scm_heap_size*2) |
| 118 | #define SCM_INIT_MALLOC_LIMIT 100000 |
| 119 | #define SCM_MTRIGGER_HYSTERESIS (SCM_INIT_MALLOC_LIMIT/10) |
| 120 | |
| 121 | /* CELL_UP and CELL_DN are used by scm_init_heap_seg to find scm_cell aligned inner |
| 122 | bounds for allocated storage */ |
| 123 | |
| 124 | #ifdef PROT386 |
| 125 | /*in 386 protected mode we must only adjust the offset */ |
| 126 | # define CELL_UP(p) MK_FP(FP_SEG(p), ~7&(FP_OFF(p)+7)) |
| 127 | # define CELL_DN(p) MK_FP(FP_SEG(p), ~7&FP_OFF(p)) |
| 128 | #else |
| 129 | # ifdef _UNICOS |
| 130 | # define CELL_UP(p) (SCM_CELLPTR)(~1L & ((long)(p)+1L)) |
| 131 | # define CELL_DN(p) (SCM_CELLPTR)(~1L & (long)(p)) |
| 132 | # else |
| 133 | # define CELL_UP(p) (SCM_CELLPTR)(~(sizeof(scm_cell)-1L) & ((long)(p)+sizeof(scm_cell)-1L)) |
| 134 | # define CELL_DN(p) (SCM_CELLPTR)(~(sizeof(scm_cell)-1L) & (long)(p)) |
| 135 | # endif /* UNICOS */ |
| 136 | #endif /* PROT386 */ |
| 137 | |
| 138 | |
| 139 | \f |
| 140 | /* scm_freelist |
| 141 | * is the head of freelist of cons pairs. |
| 142 | */ |
| 143 | SCM scm_freelist = SCM_EOL; |
| 144 | |
| 145 | /* scm_mtrigger |
| 146 | * is the number of bytes of must_malloc allocation needed to trigger gc. |
| 147 | */ |
| 148 | long scm_mtrigger; |
| 149 | |
| 150 | |
| 151 | /* scm_gc_heap_lock |
| 152 | * If set, don't expand the heap. Set only during gc, during which no allocation |
| 153 | * is supposed to take place anyway. |
| 154 | */ |
| 155 | int scm_gc_heap_lock = 0; |
| 156 | |
| 157 | /* GC Blocking |
| 158 | * Don't pause for collection if this is set -- just |
| 159 | * expand the heap. |
| 160 | */ |
| 161 | |
| 162 | int scm_block_gc = 1; |
| 163 | |
| 164 | /* If fewer than MIN_GC_YIELD cells are recovered during a garbage |
| 165 | * collection (GC) more space is allocated for the heap. |
| 166 | */ |
| 167 | #define MIN_GC_YIELD (scm_heap_size/4) |
| 168 | |
| 169 | /* During collection, this accumulates objects holding |
| 170 | * weak references. |
| 171 | */ |
| 172 | SCM *scm_weak_vectors; |
| 173 | int scm_weak_size; |
| 174 | int scm_n_weak; |
| 175 | |
| 176 | /* GC Statistics Keeping |
| 177 | */ |
| 178 | unsigned long scm_cells_allocated = 0; |
| 179 | unsigned long scm_mallocated = 0; |
| 180 | unsigned long scm_gc_cells_collected; |
| 181 | unsigned long scm_gc_malloc_collected; |
| 182 | unsigned long scm_gc_ports_collected; |
| 183 | unsigned long scm_gc_rt; |
| 184 | unsigned long scm_gc_time_taken = 0; |
| 185 | |
| 186 | SCM_SYMBOL (sym_cells_allocated, "cells-allocated"); |
| 187 | SCM_SYMBOL (sym_heap_size, "cell-heap-size"); |
| 188 | SCM_SYMBOL (sym_mallocated, "bytes-malloced"); |
| 189 | SCM_SYMBOL (sym_mtrigger, "gc-malloc-threshold"); |
| 190 | SCM_SYMBOL (sym_heap_segments, "cell-heap-segments"); |
| 191 | SCM_SYMBOL (sym_gc_time_taken, "gc-time-taken"); |
| 192 | |
| 193 | |
| 194 | struct scm_heap_seg_data |
| 195 | { |
| 196 | /* lower and upper bounds of the segment */ |
| 197 | SCM_CELLPTR bounds[2]; |
| 198 | |
| 199 | /* address of the head-of-freelist pointer for this segment's cells. |
| 200 | All segments usually point to the same one, scm_freelist. */ |
| 201 | SCM *freelistp; |
| 202 | |
| 203 | /* number of SCM words per object in this segment */ |
| 204 | int ncells; |
| 205 | |
| 206 | /* If SEG_DATA->valid is non-zero, the conservative marking |
| 207 | functions will apply SEG_DATA->valid to the purported pointer and |
| 208 | SEG_DATA, and mark the object iff the function returns non-zero. |
| 209 | At the moment, I don't think anyone uses this. */ |
| 210 | int (*valid) (); |
| 211 | }; |
| 212 | |
| 213 | |
| 214 | |
| 215 | |
| 216 | static void scm_mark_weak_vector_spines SCM_P ((void)); |
| 217 | static scm_sizet init_heap_seg SCM_P ((SCM_CELLPTR, scm_sizet, int, SCM *)); |
| 218 | static void alloc_some_heap SCM_P ((int, SCM *)); |
| 219 | |
| 220 | |
| 221 | \f |
| 222 | /* Debugging functions. */ |
| 223 | |
| 224 | #ifdef DEBUG_FREELIST |
| 225 | |
| 226 | /* Return the number of the heap segment containing CELL. */ |
| 227 | static int |
| 228 | which_seg (SCM cell) |
| 229 | { |
| 230 | int i; |
| 231 | |
| 232 | for (i = 0; i < scm_n_heap_segs; i++) |
| 233 | if (SCM_PTR_LE (scm_heap_table[i].bounds[0], (SCM_CELLPTR) cell) |
| 234 | && SCM_PTR_GT (scm_heap_table[i].bounds[1], (SCM_CELLPTR) cell)) |
| 235 | return i; |
| 236 | fprintf (stderr, "which_seg: can't find segment containing cell %lx\n", |
| 237 | cell); |
| 238 | abort (); |
| 239 | } |
| 240 | |
| 241 | |
| 242 | SCM_PROC (s_map_free_list, "map-free-list", 0, 0, 0, scm_map_free_list); |
| 243 | SCM |
| 244 | scm_map_free_list () |
| 245 | { |
| 246 | int last_seg = -1, count = 0; |
| 247 | SCM f; |
| 248 | |
| 249 | fprintf (stderr, "%d segments total\n", scm_n_heap_segs); |
| 250 | for (f = scm_freelist; SCM_NIMP (f); f = SCM_CDR (f)) |
| 251 | { |
| 252 | int this_seg = which_seg (f); |
| 253 | |
| 254 | if (this_seg != last_seg) |
| 255 | { |
| 256 | if (last_seg != -1) |
| 257 | fprintf (stderr, " %5d cells in segment %d\n", count, last_seg); |
| 258 | last_seg = this_seg; |
| 259 | count = 0; |
| 260 | } |
| 261 | count++; |
| 262 | } |
| 263 | if (last_seg != -1) |
| 264 | fprintf (stderr, " %5d cells in segment %d\n", count, last_seg); |
| 265 | |
| 266 | fflush (stderr); |
| 267 | |
| 268 | return SCM_UNSPECIFIED; |
| 269 | } |
| 270 | |
| 271 | |
| 272 | /* Number of calls to SCM_NEWCELL since startup. */ |
| 273 | static unsigned long scm_newcell_count; |
| 274 | |
| 275 | /* Search freelist for anything that isn't marked as a free cell. |
| 276 | Abort if we find something. */ |
| 277 | static void |
| 278 | scm_check_freelist () |
| 279 | { |
| 280 | SCM f; |
| 281 | int i = 0; |
| 282 | |
| 283 | for (f = scm_freelist; SCM_NIMP (f); f = SCM_CDR (f), i++) |
| 284 | if (SCM_CAR (f) != (SCM) scm_tc_free_cell) |
| 285 | { |
| 286 | fprintf (stderr, "Bad cell in freelist on newcell %lu: %d'th elt\n", |
| 287 | scm_newcell_count, i); |
| 288 | fflush (stderr); |
| 289 | abort (); |
| 290 | } |
| 291 | } |
| 292 | |
| 293 | static int scm_debug_check_freelist = 0; |
| 294 | void |
| 295 | scm_debug_newcell (SCM *into) |
| 296 | { |
| 297 | scm_newcell_count++; |
| 298 | if (scm_debug_check_freelist) |
| 299 | scm_check_freelist (); |
| 300 | |
| 301 | /* The rest of this is supposed to be identical to the SCM_NEWCELL |
| 302 | macro. */ |
| 303 | if (SCM_IMP (scm_freelist)) |
| 304 | *into = scm_gc_for_newcell (); |
| 305 | else |
| 306 | { |
| 307 | *into = scm_freelist; |
| 308 | scm_freelist = SCM_CDR (scm_freelist); |
| 309 | ++scm_cells_allocated; |
| 310 | } |
| 311 | } |
| 312 | |
| 313 | #endif /* DEBUG_FREELIST */ |
| 314 | |
| 315 | \f |
| 316 | |
| 317 | /* {Scheme Interface to GC} |
| 318 | */ |
| 319 | |
| 320 | SCM_PROC (s_gc_stats, "gc-stats", 0, 0, 0, scm_gc_stats); |
| 321 | SCM |
| 322 | scm_gc_stats () |
| 323 | { |
| 324 | int i; |
| 325 | int n; |
| 326 | SCM heap_segs; |
| 327 | SCM local_scm_mtrigger; |
| 328 | SCM local_scm_mallocated; |
| 329 | SCM local_scm_heap_size; |
| 330 | SCM local_scm_cells_allocated; |
| 331 | SCM local_scm_gc_time_taken; |
| 332 | SCM answer; |
| 333 | |
| 334 | SCM_DEFER_INTS; |
| 335 | scm_block_gc = 1; |
| 336 | retry: |
| 337 | heap_segs = SCM_EOL; |
| 338 | n = scm_n_heap_segs; |
| 339 | for (i = scm_n_heap_segs; i--; ) |
| 340 | heap_segs = scm_cons (scm_cons (scm_ulong2num ((unsigned long)scm_heap_table[i].bounds[1]), |
| 341 | scm_ulong2num ((unsigned long)scm_heap_table[i].bounds[0])), |
| 342 | heap_segs); |
| 343 | if (scm_n_heap_segs != n) |
| 344 | goto retry; |
| 345 | scm_block_gc = 0; |
| 346 | |
| 347 | local_scm_mtrigger = scm_mtrigger; |
| 348 | local_scm_mallocated = scm_mallocated; |
| 349 | local_scm_heap_size = scm_heap_size; |
| 350 | local_scm_cells_allocated = scm_cells_allocated; |
| 351 | local_scm_gc_time_taken = scm_gc_time_taken; |
| 352 | |
| 353 | answer = scm_listify (scm_cons (sym_gc_time_taken, scm_ulong2num (local_scm_gc_time_taken)), |
| 354 | scm_cons (sym_cells_allocated, scm_ulong2num (local_scm_cells_allocated)), |
| 355 | scm_cons (sym_heap_size, scm_ulong2num (local_scm_heap_size)), |
| 356 | scm_cons (sym_mallocated, scm_ulong2num (local_scm_mallocated)), |
| 357 | scm_cons (sym_mtrigger, scm_ulong2num (local_scm_mtrigger)), |
| 358 | scm_cons (sym_heap_segments, heap_segs), |
| 359 | SCM_UNDEFINED); |
| 360 | SCM_ALLOW_INTS; |
| 361 | return answer; |
| 362 | } |
| 363 | |
| 364 | |
| 365 | void |
| 366 | scm_gc_start (what) |
| 367 | char *what; |
| 368 | { |
| 369 | scm_gc_rt = SCM_INUM (scm_get_internal_run_time ()); |
| 370 | scm_gc_cells_collected = 0; |
| 371 | scm_gc_malloc_collected = 0; |
| 372 | scm_gc_ports_collected = 0; |
| 373 | } |
| 374 | |
| 375 | void |
| 376 | scm_gc_end () |
| 377 | { |
| 378 | scm_gc_rt = SCM_INUM (scm_get_internal_run_time ()) - scm_gc_rt; |
| 379 | scm_gc_time_taken = scm_gc_time_taken + scm_gc_rt; |
| 380 | scm_system_async_mark (scm_gc_async); |
| 381 | } |
| 382 | |
| 383 | |
| 384 | SCM_PROC(s_object_address, "object-address", 1, 0, 0, scm_object_addr); |
| 385 | SCM |
| 386 | scm_object_addr (obj) |
| 387 | SCM obj; |
| 388 | { |
| 389 | return scm_ulong2num ((unsigned long)obj); |
| 390 | } |
| 391 | |
| 392 | |
| 393 | SCM_PROC(s_gc, "gc", 0, 0, 0, scm_gc); |
| 394 | SCM |
| 395 | scm_gc () |
| 396 | { |
| 397 | SCM_DEFER_INTS; |
| 398 | scm_igc ("call"); |
| 399 | SCM_ALLOW_INTS; |
| 400 | return SCM_UNSPECIFIED; |
| 401 | } |
| 402 | |
| 403 | |
| 404 | \f |
| 405 | /* {C Interface For When GC is Triggered} |
| 406 | */ |
| 407 | |
| 408 | void |
| 409 | scm_gc_for_alloc (ncells, freelistp) |
| 410 | int ncells; |
| 411 | SCM * freelistp; |
| 412 | { |
| 413 | SCM_REDEFER_INTS; |
| 414 | scm_igc ("cells"); |
| 415 | if ((scm_gc_cells_collected < MIN_GC_YIELD) || SCM_IMP (*freelistp)) |
| 416 | { |
| 417 | alloc_some_heap (ncells, freelistp); |
| 418 | } |
| 419 | SCM_REALLOW_INTS; |
| 420 | } |
| 421 | |
| 422 | |
| 423 | SCM |
| 424 | scm_gc_for_newcell () |
| 425 | { |
| 426 | SCM fl; |
| 427 | scm_gc_for_alloc (1, &scm_freelist); |
| 428 | fl = scm_freelist; |
| 429 | scm_freelist = SCM_CDR (fl); |
| 430 | return fl; |
| 431 | } |
| 432 | |
| 433 | void |
| 434 | scm_igc (what) |
| 435 | char *what; |
| 436 | { |
| 437 | int j; |
| 438 | |
| 439 | #ifdef USE_THREADS |
| 440 | /* During the critical section, only the current thread may run. */ |
| 441 | SCM_THREAD_CRITICAL_SECTION_START; |
| 442 | #endif |
| 443 | |
| 444 | // fprintf (stderr, "gc: %s\n", what); |
| 445 | |
| 446 | scm_gc_start (what); |
| 447 | if (!scm_stack_base || scm_block_gc) |
| 448 | { |
| 449 | scm_gc_end (); |
| 450 | return; |
| 451 | } |
| 452 | |
| 453 | ++scm_gc_heap_lock; |
| 454 | scm_n_weak = 0; |
| 455 | |
| 456 | /* unprotect any struct types with no instances */ |
| 457 | #if 0 |
| 458 | { |
| 459 | SCM type_list; |
| 460 | SCM * pos; |
| 461 | |
| 462 | pos = &scm_type_obj_list; |
| 463 | type_list = scm_type_obj_list; |
| 464 | while (type_list != SCM_EOL) |
| 465 | if (SCM_VELTS (SCM_CAR (type_list))[scm_struct_i_refcnt]) |
| 466 | { |
| 467 | pos = SCM_CDRLOC (type_list); |
| 468 | type_list = SCM_CDR (type_list); |
| 469 | } |
| 470 | else |
| 471 | { |
| 472 | *pos = SCM_CDR (type_list); |
| 473 | type_list = SCM_CDR (type_list); |
| 474 | } |
| 475 | } |
| 476 | #endif |
| 477 | |
| 478 | /* flush dead entries from the continuation stack */ |
| 479 | { |
| 480 | int x; |
| 481 | int bound; |
| 482 | SCM * elts; |
| 483 | elts = SCM_VELTS (scm_continuation_stack); |
| 484 | bound = SCM_LENGTH (scm_continuation_stack); |
| 485 | x = SCM_INUM (scm_continuation_stack_ptr); |
| 486 | while (x < bound) |
| 487 | { |
| 488 | elts[x] = SCM_BOOL_F; |
| 489 | ++x; |
| 490 | } |
| 491 | } |
| 492 | |
| 493 | #ifndef USE_THREADS |
| 494 | |
| 495 | /* Protect from the C stack. This must be the first marking |
| 496 | * done because it provides information about what objects |
| 497 | * are "in-use" by the C code. "in-use" objects are those |
| 498 | * for which the values from SCM_LENGTH and SCM_CHARS must remain |
| 499 | * usable. This requirement is stricter than a liveness |
| 500 | * requirement -- in particular, it constrains the implementation |
| 501 | * of scm_vector_set_length_x. |
| 502 | */ |
| 503 | SCM_FLUSH_REGISTER_WINDOWS; |
| 504 | /* This assumes that all registers are saved into the jmp_buf */ |
| 505 | setjmp (scm_save_regs_gc_mark); |
| 506 | scm_mark_locations ((SCM_STACKITEM *) scm_save_regs_gc_mark, |
| 507 | ( (scm_sizet) (sizeof (SCM_STACKITEM) - 1 + |
| 508 | sizeof scm_save_regs_gc_mark) |
| 509 | / sizeof (SCM_STACKITEM))); |
| 510 | |
| 511 | { |
| 512 | /* stack_len is long rather than scm_sizet in order to guarantee that |
| 513 | &stack_len is long aligned */ |
| 514 | #ifdef SCM_STACK_GROWS_UP |
| 515 | #ifdef nosve |
| 516 | long stack_len = (SCM_STACKITEM *) (&stack_len) - scm_stack_base; |
| 517 | #else |
| 518 | long stack_len = scm_stack_size (scm_stack_base); |
| 519 | #endif |
| 520 | scm_mark_locations (scm_stack_base, (scm_sizet) stack_len); |
| 521 | #else |
| 522 | #ifdef nosve |
| 523 | long stack_len = scm_stack_base - (SCM_STACKITEM *) (&stack_len); |
| 524 | #else |
| 525 | long stack_len = scm_stack_size (scm_stack_base); |
| 526 | #endif |
| 527 | scm_mark_locations ((scm_stack_base - stack_len), (scm_sizet) stack_len); |
| 528 | #endif |
| 529 | } |
| 530 | |
| 531 | #else /* USE_THREADS */ |
| 532 | |
| 533 | /* Mark every thread's stack and registers */ |
| 534 | scm_threads_mark_stacks(); |
| 535 | |
| 536 | #endif /* USE_THREADS */ |
| 537 | |
| 538 | /* FIXME: insert a phase to un-protect string-data preserved |
| 539 | * in scm_vector_set_length_x. |
| 540 | */ |
| 541 | |
| 542 | j = SCM_NUM_PROTECTS; |
| 543 | while (j--) |
| 544 | scm_gc_mark (scm_sys_protects[j]); |
| 545 | |
| 546 | #ifndef USE_THREADS |
| 547 | scm_gc_mark (scm_root->handle); |
| 548 | #endif |
| 549 | |
| 550 | scm_mark_weak_vector_spines (); |
| 551 | |
| 552 | scm_gc_sweep (); |
| 553 | |
| 554 | --scm_gc_heap_lock; |
| 555 | scm_gc_end (); |
| 556 | |
| 557 | #ifdef USE_THREADS |
| 558 | SCM_THREAD_CRITICAL_SECTION_END; |
| 559 | #endif |
| 560 | } |
| 561 | |
| 562 | \f |
| 563 | /* {Mark/Sweep} |
| 564 | */ |
| 565 | |
| 566 | |
| 567 | |
| 568 | /* Mark an object precisely. |
| 569 | */ |
| 570 | void |
| 571 | scm_gc_mark (p) |
| 572 | SCM p; |
| 573 | { |
| 574 | register long i; |
| 575 | register SCM ptr; |
| 576 | |
| 577 | ptr = p; |
| 578 | |
| 579 | gc_mark_loop: |
| 580 | if (SCM_IMP (ptr)) |
| 581 | return; |
| 582 | |
| 583 | gc_mark_nimp: |
| 584 | if (SCM_NCELLP (ptr)) |
| 585 | scm_wta (ptr, "rogue pointer in heap", NULL); |
| 586 | |
| 587 | switch (SCM_TYP7 (ptr)) |
| 588 | { |
| 589 | case scm_tcs_cons_nimcar: |
| 590 | if (SCM_GCMARKP (ptr)) |
| 591 | break; |
| 592 | SCM_SETGCMARK (ptr); |
| 593 | if (SCM_IMP (SCM_CDR (ptr))) /* SCM_IMP works even with a GC mark */ |
| 594 | { |
| 595 | ptr = SCM_CAR (ptr); |
| 596 | goto gc_mark_nimp; |
| 597 | } |
| 598 | scm_gc_mark (SCM_CAR (ptr)); |
| 599 | ptr = SCM_GCCDR (ptr); |
| 600 | goto gc_mark_nimp; |
| 601 | case scm_tcs_cons_imcar: |
| 602 | if (SCM_GCMARKP (ptr)) |
| 603 | break; |
| 604 | SCM_SETGCMARK (ptr); |
| 605 | ptr = SCM_GCCDR (ptr); |
| 606 | goto gc_mark_loop; |
| 607 | case scm_tcs_cons_gloc: |
| 608 | if (SCM_GCMARKP (ptr)) |
| 609 | break; |
| 610 | SCM_SETGCMARK (ptr); |
| 611 | { |
| 612 | SCM vcell; |
| 613 | vcell = SCM_CAR (ptr) - 1L; |
| 614 | switch (SCM_CDR (vcell)) |
| 615 | { |
| 616 | default: |
| 617 | scm_gc_mark (vcell); |
| 618 | ptr = SCM_GCCDR (ptr); |
| 619 | goto gc_mark_loop; |
| 620 | case 1: /* ! */ |
| 621 | case 0: /* ! */ |
| 622 | { |
| 623 | SCM layout; |
| 624 | SCM * vtable_data; |
| 625 | int len; |
| 626 | char * fields_desc; |
| 627 | register SCM * mem; |
| 628 | register int x; |
| 629 | |
| 630 | vtable_data = (SCM *)vcell; |
| 631 | layout = vtable_data[scm_vtable_index_layout]; |
| 632 | len = SCM_LENGTH (layout); |
| 633 | fields_desc = SCM_CHARS (layout); |
| 634 | /* We're using SCM_GCCDR here like STRUCT_DATA, except |
| 635 | that it removes the mark */ |
| 636 | mem = (SCM *)SCM_GCCDR (ptr); |
| 637 | |
| 638 | if (len) |
| 639 | { |
| 640 | for (x = 0; x < len - 2; x += 2, ++mem) |
| 641 | if (fields_desc[x] == 'p') |
| 642 | scm_gc_mark (*mem); |
| 643 | if (fields_desc[x] == 'p') |
| 644 | { |
| 645 | if (SCM_LAYOUT_TAILP (fields_desc[x + 1])) |
| 646 | for (x = *mem; x; --x) |
| 647 | scm_gc_mark (*++mem); |
| 648 | else |
| 649 | scm_gc_mark (*mem); |
| 650 | } |
| 651 | } |
| 652 | if (!SCM_CDR (vcell)) |
| 653 | { |
| 654 | SCM_SETGCMARK (vcell); |
| 655 | ptr = vtable_data[scm_vtable_index_vtable]; |
| 656 | goto gc_mark_loop; |
| 657 | } |
| 658 | } |
| 659 | } |
| 660 | } |
| 661 | break; |
| 662 | case scm_tcs_closures: |
| 663 | if (SCM_GCMARKP (ptr)) |
| 664 | break; |
| 665 | SCM_SETGCMARK (ptr); |
| 666 | if (SCM_IMP (SCM_CDR (ptr))) |
| 667 | { |
| 668 | ptr = SCM_CLOSCAR (ptr); |
| 669 | goto gc_mark_nimp; |
| 670 | } |
| 671 | scm_gc_mark (SCM_CLOSCAR (ptr)); |
| 672 | ptr = SCM_GCCDR (ptr); |
| 673 | goto gc_mark_nimp; |
| 674 | case scm_tc7_vector: |
| 675 | case scm_tc7_lvector: |
| 676 | #ifdef CCLO |
| 677 | case scm_tc7_cclo: |
| 678 | #endif |
| 679 | if (SCM_GC8MARKP (ptr)) |
| 680 | break; |
| 681 | SCM_SETGC8MARK (ptr); |
| 682 | i = SCM_LENGTH (ptr); |
| 683 | if (i == 0) |
| 684 | break; |
| 685 | while (--i > 0) |
| 686 | if (SCM_NIMP (SCM_VELTS (ptr)[i])) |
| 687 | scm_gc_mark (SCM_VELTS (ptr)[i]); |
| 688 | ptr = SCM_VELTS (ptr)[0]; |
| 689 | goto gc_mark_loop; |
| 690 | case scm_tc7_contin: |
| 691 | if SCM_GC8MARKP |
| 692 | (ptr) break; |
| 693 | SCM_SETGC8MARK (ptr); |
| 694 | if (SCM_VELTS (ptr)) |
| 695 | scm_mark_locations (SCM_VELTS (ptr), |
| 696 | (scm_sizet) |
| 697 | (SCM_LENGTH (ptr) + |
| 698 | (sizeof (SCM_STACKITEM) + -1 + |
| 699 | sizeof (scm_contregs)) / |
| 700 | sizeof (SCM_STACKITEM))); |
| 701 | break; |
| 702 | case scm_tc7_bvect: |
| 703 | case scm_tc7_byvect: |
| 704 | case scm_tc7_ivect: |
| 705 | case scm_tc7_uvect: |
| 706 | case scm_tc7_fvect: |
| 707 | case scm_tc7_dvect: |
| 708 | case scm_tc7_cvect: |
| 709 | case scm_tc7_svect: |
| 710 | #ifdef LONGLONGS |
| 711 | case scm_tc7_llvect: |
| 712 | #endif |
| 713 | |
| 714 | case scm_tc7_string: |
| 715 | case scm_tc7_mb_string: |
| 716 | SCM_SETGC8MARK (ptr); |
| 717 | break; |
| 718 | |
| 719 | case scm_tc7_substring: |
| 720 | case scm_tc7_mb_substring: |
| 721 | if (SCM_GC8MARKP(ptr)) |
| 722 | break; |
| 723 | SCM_SETGC8MARK (ptr); |
| 724 | ptr = SCM_CDR (ptr); |
| 725 | goto gc_mark_loop; |
| 726 | |
| 727 | case scm_tc7_wvect: |
| 728 | if (SCM_GC8MARKP(ptr)) |
| 729 | break; |
| 730 | scm_weak_vectors[scm_n_weak++] = ptr; |
| 731 | if (scm_n_weak >= scm_weak_size) |
| 732 | { |
| 733 | SCM_SYSCALL (scm_weak_vectors = |
| 734 | (SCM *) realloc ((char *) scm_weak_vectors, |
| 735 | sizeof (SCM *) * (scm_weak_size *= 2))); |
| 736 | if (scm_weak_vectors == NULL) |
| 737 | { |
| 738 | scm_gen_puts (scm_regular_string, |
| 739 | "weak vector table", |
| 740 | scm_cur_errp); |
| 741 | scm_gen_puts (scm_regular_string, |
| 742 | "\nFATAL ERROR DURING CRITICAL SCM_CODE SECTION\n", |
| 743 | scm_cur_errp); |
| 744 | exit(SCM_EXIT_FAILURE); |
| 745 | } |
| 746 | } |
| 747 | SCM_SETGC8MARK (ptr); |
| 748 | if (SCM_IS_WHVEC_ANY (ptr)) |
| 749 | { |
| 750 | int x; |
| 751 | int len; |
| 752 | int weak_keys; |
| 753 | int weak_values; |
| 754 | |
| 755 | len = SCM_LENGTH (ptr); |
| 756 | weak_keys = SCM_IS_WHVEC (ptr) || SCM_IS_WHVEC_B (ptr); |
| 757 | weak_values = SCM_IS_WHVEC_V (ptr) || SCM_IS_WHVEC_B (ptr); |
| 758 | |
| 759 | for (x = 0; x < len; ++x) |
| 760 | { |
| 761 | SCM alist; |
| 762 | alist = SCM_VELTS (ptr)[x]; |
| 763 | /* mark everything on the alist |
| 764 | * except the keys or values, according to weak_values and weak_keys. |
| 765 | */ |
| 766 | while ( SCM_NIMP (alist) |
| 767 | && SCM_CONSP (alist) |
| 768 | && !SCM_GCMARKP (alist) |
| 769 | && SCM_NIMP (SCM_CAR (alist)) |
| 770 | && SCM_CONSP (SCM_CAR (alist))) |
| 771 | { |
| 772 | SCM kvpair; |
| 773 | SCM next_alist; |
| 774 | |
| 775 | kvpair = SCM_CAR (alist); |
| 776 | next_alist = SCM_CDR (alist); |
| 777 | /* |
| 778 | * Do not do this: |
| 779 | * SCM_SETGCMARK (alist); |
| 780 | * SCM_SETGCMARK (kvpair); |
| 781 | * |
| 782 | * It may be that either the key or value is protected by |
| 783 | * an escaped reference to part of the spine of this alist. |
| 784 | * If we mark the spine here, and only mark one or neither of the |
| 785 | * key and value, they may never be properly marked. |
| 786 | * This leads to a horrible situation in which an alist containing |
| 787 | * freelist cells is exported. |
| 788 | * |
| 789 | * So only mark the spines of these arrays last of all marking. |
| 790 | * If somebody confuses us by constructing a weak vector |
| 791 | * with a circular alist then we are hosed, but at least we |
| 792 | * won't prematurely drop table entries. |
| 793 | */ |
| 794 | if (!weak_keys) |
| 795 | scm_gc_mark (SCM_CAR (kvpair)); |
| 796 | if (!weak_values) |
| 797 | scm_gc_mark (SCM_GCCDR (kvpair)); |
| 798 | alist = next_alist; |
| 799 | } |
| 800 | if (SCM_NIMP (alist)) |
| 801 | scm_gc_mark (alist); |
| 802 | } |
| 803 | } |
| 804 | break; |
| 805 | |
| 806 | case scm_tc7_msymbol: |
| 807 | if (SCM_GC8MARKP(ptr)) |
| 808 | break; |
| 809 | SCM_SETGC8MARK (ptr); |
| 810 | scm_gc_mark (SCM_SYMBOL_FUNC (ptr)); |
| 811 | ptr = SCM_SYMBOL_PROPS (ptr); |
| 812 | goto gc_mark_loop; |
| 813 | case scm_tc7_ssymbol: |
| 814 | if (SCM_GC8MARKP(ptr)) |
| 815 | break; |
| 816 | SCM_SETGC8MARK (ptr); |
| 817 | break; |
| 818 | case scm_tcs_subrs: |
| 819 | ptr = (SCM)(scm_heap_org + (((unsigned long)SCM_CAR (ptr)) >> 8)); |
| 820 | goto gc_mark_loop; |
| 821 | case scm_tc7_port: |
| 822 | i = SCM_PTOBNUM (ptr); |
| 823 | if (!(i < scm_numptob)) |
| 824 | goto def; |
| 825 | if (SCM_GC8MARKP (ptr)) |
| 826 | break; |
| 827 | if (SCM_PTAB_ENTRY(ptr)) |
| 828 | scm_gc_mark (SCM_PTAB_ENTRY(ptr)->file_name); |
| 829 | ptr = (scm_ptobs[i].mark) (ptr); |
| 830 | goto gc_mark_loop; |
| 831 | break; |
| 832 | case scm_tc7_smob: |
| 833 | if (SCM_GC8MARKP (ptr)) |
| 834 | break; |
| 835 | switch SCM_TYP16 (ptr) |
| 836 | { /* should be faster than going through scm_smobs */ |
| 837 | case scm_tc_free_cell: |
| 838 | /* printf("found free_cell %X ", ptr); fflush(stdout); */ |
| 839 | SCM_SETGC8MARK (ptr); |
| 840 | SCM_SETCDR (ptr, SCM_EOL); |
| 841 | break; |
| 842 | case scm_tcs_bignums: |
| 843 | case scm_tc16_flo: |
| 844 | SCM_SETGC8MARK (ptr); |
| 845 | break; |
| 846 | default: |
| 847 | i = SCM_SMOBNUM (ptr); |
| 848 | if (!(i < scm_numsmob)) |
| 849 | goto def; |
| 850 | ptr = (scm_smobs[i].mark) (ptr); |
| 851 | goto gc_mark_loop; |
| 852 | } |
| 853 | break; |
| 854 | default: |
| 855 | def:scm_wta (ptr, "unknown type in ", "gc_mark"); |
| 856 | } |
| 857 | } |
| 858 | |
| 859 | |
| 860 | /* Mark a Region Conservatively |
| 861 | */ |
| 862 | |
| 863 | void |
| 864 | scm_mark_locations (x, n) |
| 865 | SCM_STACKITEM x[]; |
| 866 | scm_sizet n; |
| 867 | { |
| 868 | register long m = n; |
| 869 | register int i, j; |
| 870 | register SCM_CELLPTR ptr; |
| 871 | |
| 872 | while (0 <= --m) |
| 873 | if SCM_CELLP (*(SCM **) & x[m]) |
| 874 | { |
| 875 | ptr = (SCM_CELLPTR) SCM2PTR ((*(SCM **) & x[m])); |
| 876 | i = 0; |
| 877 | j = scm_n_heap_segs - 1; |
| 878 | if ( SCM_PTR_LE (scm_heap_table[i].bounds[0], ptr) |
| 879 | && SCM_PTR_GT (scm_heap_table[j].bounds[1], ptr)) |
| 880 | { |
| 881 | while (i <= j) |
| 882 | { |
| 883 | int seg_id; |
| 884 | seg_id = -1; |
| 885 | if ( (i == j) |
| 886 | || SCM_PTR_GT (scm_heap_table[i].bounds[1], ptr)) |
| 887 | seg_id = i; |
| 888 | else if (SCM_PTR_LE (scm_heap_table[j].bounds[0], ptr)) |
| 889 | seg_id = j; |
| 890 | else |
| 891 | { |
| 892 | int k; |
| 893 | k = (i + j) / 2; |
| 894 | if (k == i) |
| 895 | break; |
| 896 | if (SCM_PTR_GT (scm_heap_table[k].bounds[1], ptr)) |
| 897 | { |
| 898 | j = k; |
| 899 | ++i; |
| 900 | if (SCM_PTR_LE (scm_heap_table[i].bounds[0], ptr)) |
| 901 | continue; |
| 902 | else |
| 903 | break; |
| 904 | } |
| 905 | else if (SCM_PTR_LE (scm_heap_table[k].bounds[0], ptr)) |
| 906 | { |
| 907 | i = k; |
| 908 | --j; |
| 909 | if (SCM_PTR_GT (scm_heap_table[j].bounds[1], ptr)) |
| 910 | continue; |
| 911 | else |
| 912 | break; |
| 913 | } |
| 914 | } |
| 915 | if ( !scm_heap_table[seg_id].valid |
| 916 | || scm_heap_table[seg_id].valid (ptr, |
| 917 | &scm_heap_table[seg_id])) |
| 918 | scm_gc_mark (*(SCM *) & x[m]); |
| 919 | break; |
| 920 | } |
| 921 | |
| 922 | } |
| 923 | } |
| 924 | } |
| 925 | |
| 926 | |
| 927 | /* The following is a C predicate which determines if an SCM value can be |
| 928 | regarded as a pointer to a cell on the heap. The code is duplicated |
| 929 | from scm_mark_locations. */ |
| 930 | |
| 931 | |
| 932 | int |
| 933 | scm_cellp (value) |
| 934 | SCM value; |
| 935 | { |
| 936 | register int i, j; |
| 937 | register SCM_CELLPTR ptr; |
| 938 | |
| 939 | if SCM_CELLP (*(SCM **) & value) |
| 940 | { |
| 941 | ptr = (SCM_CELLPTR) SCM2PTR ((*(SCM **) & value)); |
| 942 | i = 0; |
| 943 | j = scm_n_heap_segs - 1; |
| 944 | if ( SCM_PTR_LE (scm_heap_table[i].bounds[0], ptr) |
| 945 | && SCM_PTR_GT (scm_heap_table[j].bounds[1], ptr)) |
| 946 | { |
| 947 | while (i <= j) |
| 948 | { |
| 949 | int seg_id; |
| 950 | seg_id = -1; |
| 951 | if ( (i == j) |
| 952 | || SCM_PTR_GT (scm_heap_table[i].bounds[1], ptr)) |
| 953 | seg_id = i; |
| 954 | else if (SCM_PTR_LE (scm_heap_table[j].bounds[0], ptr)) |
| 955 | seg_id = j; |
| 956 | else |
| 957 | { |
| 958 | int k; |
| 959 | k = (i + j) / 2; |
| 960 | if (k == i) |
| 961 | break; |
| 962 | if (SCM_PTR_GT (scm_heap_table[k].bounds[1], ptr)) |
| 963 | { |
| 964 | j = k; |
| 965 | ++i; |
| 966 | if (SCM_PTR_LE (scm_heap_table[i].bounds[0], ptr)) |
| 967 | continue; |
| 968 | else |
| 969 | break; |
| 970 | } |
| 971 | else if (SCM_PTR_LE (scm_heap_table[k].bounds[0], ptr)) |
| 972 | { |
| 973 | i = k; |
| 974 | --j; |
| 975 | if (SCM_PTR_GT (scm_heap_table[j].bounds[1], ptr)) |
| 976 | continue; |
| 977 | else |
| 978 | break; |
| 979 | } |
| 980 | } |
| 981 | if ( !scm_heap_table[seg_id].valid |
| 982 | || scm_heap_table[seg_id].valid (ptr, |
| 983 | &scm_heap_table[seg_id])) |
| 984 | return 1; |
| 985 | break; |
| 986 | } |
| 987 | |
| 988 | } |
| 989 | } |
| 990 | return 0; |
| 991 | } |
| 992 | |
| 993 | |
| 994 | static void |
| 995 | scm_mark_weak_vector_spines () |
| 996 | { |
| 997 | int i; |
| 998 | |
| 999 | for (i = 0; i < scm_n_weak; ++i) |
| 1000 | { |
| 1001 | if (SCM_IS_WHVEC_ANY (scm_weak_vectors[i])) |
| 1002 | { |
| 1003 | SCM *ptr; |
| 1004 | SCM obj; |
| 1005 | int j; |
| 1006 | int n; |
| 1007 | |
| 1008 | obj = scm_weak_vectors[i]; |
| 1009 | ptr = SCM_VELTS (scm_weak_vectors[i]); |
| 1010 | n = SCM_LENGTH (scm_weak_vectors[i]); |
| 1011 | for (j = 0; j < n; ++j) |
| 1012 | { |
| 1013 | SCM alist; |
| 1014 | |
| 1015 | alist = ptr[j]; |
| 1016 | while ( SCM_NIMP (alist) |
| 1017 | && SCM_CONSP (alist) |
| 1018 | && !SCM_GCMARKP (alist) |
| 1019 | && SCM_NIMP (SCM_CAR (alist)) |
| 1020 | && SCM_CONSP (SCM_CAR (alist))) |
| 1021 | { |
| 1022 | SCM_SETGCMARK (alist); |
| 1023 | SCM_SETGCMARK (SCM_CAR (alist)); |
| 1024 | alist = SCM_GCCDR (alist); |
| 1025 | } |
| 1026 | } |
| 1027 | } |
| 1028 | } |
| 1029 | } |
| 1030 | |
| 1031 | |
| 1032 | |
| 1033 | void |
| 1034 | scm_gc_sweep () |
| 1035 | { |
| 1036 | register SCM_CELLPTR ptr; |
| 1037 | #ifdef SCM_POINTERS_MUNGED |
| 1038 | register SCM scmptr; |
| 1039 | #else |
| 1040 | #undef scmptr |
| 1041 | #define scmptr (SCM)ptr |
| 1042 | #endif |
| 1043 | register SCM nfreelist; |
| 1044 | register SCM *hp_freelist; |
| 1045 | register long n; |
| 1046 | register long m; |
| 1047 | register scm_sizet j; |
| 1048 | register int span; |
| 1049 | scm_sizet i; |
| 1050 | scm_sizet seg_size; |
| 1051 | |
| 1052 | n = 0; |
| 1053 | m = 0; |
| 1054 | |
| 1055 | /* Reset all free list pointers. We'll reconstruct them completely |
| 1056 | while scanning. */ |
| 1057 | for (i = 0; i < scm_n_heap_segs; i++) |
| 1058 | *scm_heap_table[i].freelistp = SCM_EOL; |
| 1059 | |
| 1060 | for (i = 0; i < scm_n_heap_segs; i++) |
| 1061 | { |
| 1062 | /* Unmarked cells go onto the front of the freelist this heap |
| 1063 | segment points to. Rather than updating the real freelist |
| 1064 | pointer as we go along, we accumulate the new head in |
| 1065 | nfreelist. Then, if it turns out that the entire segment is |
| 1066 | free, we free (i.e., malloc's free) the whole segment, and |
| 1067 | simply don't assign nfreelist back into the real freelist. */ |
| 1068 | hp_freelist = scm_heap_table[i].freelistp; |
| 1069 | nfreelist = *hp_freelist; |
| 1070 | |
| 1071 | span = scm_heap_table[i].ncells; |
| 1072 | ptr = CELL_UP (scm_heap_table[i].bounds[0]); |
| 1073 | seg_size = CELL_DN (scm_heap_table[i].bounds[1]) - ptr; |
| 1074 | for (j = seg_size + span; j -= span; ptr += span) |
| 1075 | { |
| 1076 | #ifdef SCM_POINTERS_MUNGED |
| 1077 | scmptr = PTR2SCM (ptr); |
| 1078 | #endif |
| 1079 | switch SCM_TYP7 (scmptr) |
| 1080 | { |
| 1081 | case scm_tcs_cons_gloc: |
| 1082 | if (SCM_GCMARKP (scmptr)) |
| 1083 | { |
| 1084 | if (SCM_CDR (SCM_CAR (scmptr) - 1) == (SCM)1) |
| 1085 | SCM_SETCDR (SCM_CAR (scmptr) - 1, (SCM) 0); |
| 1086 | goto cmrkcontinue; |
| 1087 | } |
| 1088 | { |
| 1089 | SCM vcell; |
| 1090 | vcell = SCM_CAR (scmptr) - 1L; |
| 1091 | |
| 1092 | if ((SCM_CDR (vcell) == 0) || (SCM_CDR (vcell) == 1)) |
| 1093 | { |
| 1094 | SCM *p = (SCM *) SCM_GCCDR (scmptr); |
| 1095 | m += p[scm_struct_i_n_words] * sizeof (SCM); |
| 1096 | /* I feel like I'm programming in BCPL here... */ |
| 1097 | free ((char *) p[scm_struct_i_ptr]); |
| 1098 | } |
| 1099 | } |
| 1100 | break; |
| 1101 | case scm_tcs_cons_imcar: |
| 1102 | case scm_tcs_cons_nimcar: |
| 1103 | case scm_tcs_closures: |
| 1104 | if (SCM_GCMARKP (scmptr)) |
| 1105 | goto cmrkcontinue; |
| 1106 | break; |
| 1107 | case scm_tc7_wvect: |
| 1108 | if (SCM_GC8MARKP (scmptr)) |
| 1109 | { |
| 1110 | goto c8mrkcontinue; |
| 1111 | } |
| 1112 | else |
| 1113 | { |
| 1114 | m += (1 + SCM_LENGTH (scmptr)) * sizeof (SCM); |
| 1115 | scm_must_free ((char *)(SCM_VELTS (scmptr) - 1)); |
| 1116 | break; |
| 1117 | } |
| 1118 | |
| 1119 | case scm_tc7_vector: |
| 1120 | case scm_tc7_lvector: |
| 1121 | #ifdef CCLO |
| 1122 | case scm_tc7_cclo: |
| 1123 | #endif |
| 1124 | if (SCM_GC8MARKP (scmptr)) |
| 1125 | goto c8mrkcontinue; |
| 1126 | |
| 1127 | m += (SCM_LENGTH (scmptr) * sizeof (SCM)); |
| 1128 | freechars: |
| 1129 | scm_must_free (SCM_CHARS (scmptr)); |
| 1130 | /* SCM_SETCHARS(scmptr, 0);*/ |
| 1131 | break; |
| 1132 | case scm_tc7_bvect: |
| 1133 | if SCM_GC8MARKP (scmptr) |
| 1134 | goto c8mrkcontinue; |
| 1135 | m += sizeof (long) * ((SCM_HUGE_LENGTH (scmptr) + SCM_LONG_BIT - 1) / SCM_LONG_BIT); |
| 1136 | goto freechars; |
| 1137 | case scm_tc7_byvect: |
| 1138 | if SCM_GC8MARKP (scmptr) |
| 1139 | goto c8mrkcontinue; |
| 1140 | m += SCM_HUGE_LENGTH (scmptr) * sizeof (char); |
| 1141 | goto freechars; |
| 1142 | case scm_tc7_ivect: |
| 1143 | case scm_tc7_uvect: |
| 1144 | if SCM_GC8MARKP (scmptr) |
| 1145 | goto c8mrkcontinue; |
| 1146 | m += SCM_HUGE_LENGTH (scmptr) * sizeof (long); |
| 1147 | goto freechars; |
| 1148 | case scm_tc7_svect: |
| 1149 | if SCM_GC8MARKP (scmptr) |
| 1150 | goto c8mrkcontinue; |
| 1151 | m += SCM_HUGE_LENGTH (scmptr) * sizeof (short); |
| 1152 | goto freechars; |
| 1153 | #ifdef LONGLONGS |
| 1154 | case scm_tc7_llvect: |
| 1155 | if SCM_GC8MARKP (scmptr) |
| 1156 | goto c8mrkcontinue; |
| 1157 | m += SCM_HUGE_LENGTH (scmptr) * sizeof (long_long); |
| 1158 | goto freechars; |
| 1159 | #endif |
| 1160 | case scm_tc7_fvect: |
| 1161 | if SCM_GC8MARKP (scmptr) |
| 1162 | goto c8mrkcontinue; |
| 1163 | m += SCM_HUGE_LENGTH (scmptr) * sizeof (float); |
| 1164 | goto freechars; |
| 1165 | case scm_tc7_dvect: |
| 1166 | if SCM_GC8MARKP (scmptr) |
| 1167 | goto c8mrkcontinue; |
| 1168 | m += SCM_HUGE_LENGTH (scmptr) * sizeof (double); |
| 1169 | goto freechars; |
| 1170 | case scm_tc7_cvect: |
| 1171 | if SCM_GC8MARKP (scmptr) |
| 1172 | goto c8mrkcontinue; |
| 1173 | m += SCM_HUGE_LENGTH (scmptr) * 2 * sizeof (double); |
| 1174 | goto freechars; |
| 1175 | case scm_tc7_substring: |
| 1176 | case scm_tc7_mb_substring: |
| 1177 | if (SCM_GC8MARKP (scmptr)) |
| 1178 | goto c8mrkcontinue; |
| 1179 | break; |
| 1180 | case scm_tc7_string: |
| 1181 | case scm_tc7_mb_string: |
| 1182 | if (SCM_GC8MARKP (scmptr)) |
| 1183 | goto c8mrkcontinue; |
| 1184 | m += SCM_HUGE_LENGTH (scmptr) + 1; |
| 1185 | goto freechars; |
| 1186 | case scm_tc7_msymbol: |
| 1187 | if (SCM_GC8MARKP (scmptr)) |
| 1188 | goto c8mrkcontinue; |
| 1189 | m += ( SCM_LENGTH (scmptr) |
| 1190 | + 1 |
| 1191 | + sizeof (SCM) * ((SCM *)SCM_CHARS (scmptr) - SCM_SLOTS(scmptr))); |
| 1192 | scm_must_free ((char *)SCM_SLOTS (scmptr)); |
| 1193 | break; |
| 1194 | case scm_tc7_contin: |
| 1195 | if SCM_GC8MARKP (scmptr) |
| 1196 | goto c8mrkcontinue; |
| 1197 | m += SCM_LENGTH (scmptr) * sizeof (SCM_STACKITEM) + sizeof (scm_contregs); |
| 1198 | if (SCM_VELTS (scmptr)) |
| 1199 | goto freechars; |
| 1200 | case scm_tc7_ssymbol: |
| 1201 | if SCM_GC8MARKP(scmptr) |
| 1202 | goto c8mrkcontinue; |
| 1203 | break; |
| 1204 | case scm_tcs_subrs: |
| 1205 | continue; |
| 1206 | case scm_tc7_port: |
| 1207 | if SCM_GC8MARKP (scmptr) |
| 1208 | goto c8mrkcontinue; |
| 1209 | if SCM_OPENP (scmptr) |
| 1210 | { |
| 1211 | int k = SCM_PTOBNUM (scmptr); |
| 1212 | if (!(k < scm_numptob)) |
| 1213 | goto sweeperr; |
| 1214 | /* Keep "revealed" ports alive. */ |
| 1215 | if (scm_revealed_count(scmptr) > 0) |
| 1216 | continue; |
| 1217 | /* Yes, I really do mean scm_ptobs[k].free */ |
| 1218 | /* rather than ftobs[k].close. .close */ |
| 1219 | /* is for explicit CLOSE-PORT by user */ |
| 1220 | (scm_ptobs[k].free) (SCM_STREAM (scmptr)); |
| 1221 | SCM_SETSTREAM (scmptr, 0); |
| 1222 | scm_remove_from_port_table (scmptr); |
| 1223 | scm_gc_ports_collected++; |
| 1224 | SCM_SETAND_CAR (scmptr, ~SCM_OPN); |
| 1225 | } |
| 1226 | break; |
| 1227 | case scm_tc7_smob: |
| 1228 | switch SCM_GCTYP16 (scmptr) |
| 1229 | { |
| 1230 | case scm_tc_free_cell: |
| 1231 | if SCM_GC8MARKP (scmptr) |
| 1232 | goto c8mrkcontinue; |
| 1233 | break; |
| 1234 | #ifdef SCM_BIGDIG |
| 1235 | case scm_tcs_bignums: |
| 1236 | if SCM_GC8MARKP (scmptr) |
| 1237 | goto c8mrkcontinue; |
| 1238 | m += (SCM_NUMDIGS (scmptr) * SCM_BITSPERDIG / SCM_CHAR_BIT); |
| 1239 | goto freechars; |
| 1240 | #endif /* def SCM_BIGDIG */ |
| 1241 | case scm_tc16_flo: |
| 1242 | if SCM_GC8MARKP (scmptr) |
| 1243 | goto c8mrkcontinue; |
| 1244 | switch ((int) (SCM_CAR (scmptr) >> 16)) |
| 1245 | { |
| 1246 | case (SCM_IMAG_PART | SCM_REAL_PART) >> 16: |
| 1247 | m += sizeof (double); |
| 1248 | case SCM_REAL_PART >> 16: |
| 1249 | case SCM_IMAG_PART >> 16: |
| 1250 | m += sizeof (double); |
| 1251 | goto freechars; |
| 1252 | case 0: |
| 1253 | break; |
| 1254 | default: |
| 1255 | goto sweeperr; |
| 1256 | } |
| 1257 | break; |
| 1258 | default: |
| 1259 | if SCM_GC8MARKP (scmptr) |
| 1260 | goto c8mrkcontinue; |
| 1261 | |
| 1262 | { |
| 1263 | int k; |
| 1264 | k = SCM_SMOBNUM (scmptr); |
| 1265 | if (!(k < scm_numsmob)) |
| 1266 | goto sweeperr; |
| 1267 | m += (scm_smobs[k].free) ((SCM) scmptr); |
| 1268 | break; |
| 1269 | } |
| 1270 | } |
| 1271 | break; |
| 1272 | default: |
| 1273 | sweeperr:scm_wta (scmptr, "unknown type in ", "gc_sweep"); |
| 1274 | } |
| 1275 | n += span; |
| 1276 | #if 0 |
| 1277 | if (SCM_CAR (scmptr) == (SCM) scm_tc_free_cell) |
| 1278 | exit (2); |
| 1279 | #endif |
| 1280 | /* Stick the new cell on the front of nfreelist. */ |
| 1281 | SCM_SETCAR (scmptr, (SCM) scm_tc_free_cell); |
| 1282 | SCM_SETCDR (scmptr, nfreelist); |
| 1283 | nfreelist = scmptr; |
| 1284 | |
| 1285 | continue; |
| 1286 | c8mrkcontinue: |
| 1287 | SCM_CLRGC8MARK (scmptr); |
| 1288 | continue; |
| 1289 | cmrkcontinue: |
| 1290 | SCM_CLRGCMARK (scmptr); |
| 1291 | } |
| 1292 | #ifdef GC_FREE_SEGMENTS |
| 1293 | if (n == seg_size) |
| 1294 | { |
| 1295 | scm_heap_size -= seg_size; |
| 1296 | free ((char *) scm_heap_table[i].bounds[0]); |
| 1297 | scm_heap_table[i].bounds[0] = 0; |
| 1298 | for (j = i + 1; j < scm_n_heap_segs; j++) |
| 1299 | scm_heap_table[j - 1] = scm_heap_table[j]; |
| 1300 | scm_n_heap_segs -= 1; |
| 1301 | i--; /* We need to scan the segment just moved. */ |
| 1302 | } |
| 1303 | else |
| 1304 | #endif /* ifdef GC_FREE_SEGMENTS */ |
| 1305 | /* Update the real freelist pointer to point to the head of |
| 1306 | the list of free cells we've built for this segment. */ |
| 1307 | *hp_freelist = nfreelist; |
| 1308 | |
| 1309 | #ifdef DEBUG_FREELIST |
| 1310 | scm_check_freelist (); |
| 1311 | scm_map_free_list (); |
| 1312 | #endif |
| 1313 | |
| 1314 | scm_gc_cells_collected += n; |
| 1315 | n = 0; |
| 1316 | } |
| 1317 | /* Scan weak vectors. */ |
| 1318 | { |
| 1319 | SCM *ptr; |
| 1320 | for (i = 0; i < scm_n_weak; ++i) |
| 1321 | { |
| 1322 | if (!SCM_IS_WHVEC_ANY (scm_weak_vectors[i])) |
| 1323 | { |
| 1324 | ptr = SCM_VELTS (scm_weak_vectors[i]); |
| 1325 | n = SCM_LENGTH (scm_weak_vectors[i]); |
| 1326 | for (j = 0; j < n; ++j) |
| 1327 | if (SCM_NIMP (ptr[j]) && SCM_FREEP (ptr[j])) |
| 1328 | ptr[j] = SCM_BOOL_F; |
| 1329 | } |
| 1330 | else /* if (SCM_IS_WHVEC_ANY (scm_weak_vectors[i])) */ |
| 1331 | { |
| 1332 | SCM obj; |
| 1333 | obj = scm_weak_vectors[i]; |
| 1334 | ptr = SCM_VELTS (scm_weak_vectors[i]); |
| 1335 | n = SCM_LENGTH (scm_weak_vectors[i]); |
| 1336 | for (j = 0; j < n; ++j) |
| 1337 | { |
| 1338 | SCM * fixup; |
| 1339 | SCM alist; |
| 1340 | int weak_keys; |
| 1341 | int weak_values; |
| 1342 | |
| 1343 | weak_keys = SCM_IS_WHVEC (obj) || SCM_IS_WHVEC_B (obj); |
| 1344 | weak_values = SCM_IS_WHVEC_V (obj) || SCM_IS_WHVEC_B (obj); |
| 1345 | |
| 1346 | fixup = ptr + j; |
| 1347 | alist = *fixup; |
| 1348 | |
| 1349 | while (SCM_NIMP (alist) |
| 1350 | && SCM_CONSP (alist) |
| 1351 | && SCM_NIMP (SCM_CAR (alist)) |
| 1352 | && SCM_CONSP (SCM_CAR (alist))) |
| 1353 | { |
| 1354 | SCM key; |
| 1355 | SCM value; |
| 1356 | |
| 1357 | key = SCM_CAAR (alist); |
| 1358 | value = SCM_CDAR (alist); |
| 1359 | if ( (weak_keys && SCM_NIMP (key) && SCM_FREEP (key)) |
| 1360 | || (weak_values && SCM_NIMP (value) && SCM_FREEP (value))) |
| 1361 | { |
| 1362 | *fixup = SCM_CDR (alist); |
| 1363 | } |
| 1364 | else |
| 1365 | fixup = SCM_CDRLOC (alist); |
| 1366 | alist = SCM_CDR (alist); |
| 1367 | } |
| 1368 | } |
| 1369 | } |
| 1370 | } |
| 1371 | } |
| 1372 | scm_cells_allocated = (scm_heap_size - scm_gc_cells_collected); |
| 1373 | scm_mallocated -= m; |
| 1374 | scm_gc_malloc_collected = m; |
| 1375 | } |
| 1376 | |
| 1377 | |
| 1378 | \f |
| 1379 | |
| 1380 | /* {Front end to malloc} |
| 1381 | * |
| 1382 | * scm_must_malloc, scm_must_realloc, scm_must_free, scm_done_malloc |
| 1383 | * |
| 1384 | * These functions provide services comperable to malloc, realloc, and |
| 1385 | * free. They are for allocating malloced parts of scheme objects. |
| 1386 | * The primary purpose of the front end is to impose calls to gc. |
| 1387 | */ |
| 1388 | |
| 1389 | /* scm_must_malloc |
| 1390 | * Return newly malloced storage or throw an error. |
| 1391 | * |
| 1392 | * The parameter WHAT is a string for error reporting. |
| 1393 | * If the threshold scm_mtrigger will be passed by this |
| 1394 | * allocation, or if the first call to malloc fails, |
| 1395 | * garbage collect -- on the presumption that some objects |
| 1396 | * using malloced storage may be collected. |
| 1397 | * |
| 1398 | * The limit scm_mtrigger may be raised by this allocation. |
| 1399 | */ |
| 1400 | char * |
| 1401 | scm_must_malloc (len, what) |
| 1402 | long len; |
| 1403 | char *what; |
| 1404 | { |
| 1405 | char *ptr; |
| 1406 | scm_sizet size = len; |
| 1407 | long nm = scm_mallocated + size; |
| 1408 | if (len != size) |
| 1409 | malerr: |
| 1410 | scm_wta (SCM_MAKINUM (len), (char *) SCM_NALLOC, what); |
| 1411 | if ((nm <= scm_mtrigger)) |
| 1412 | { |
| 1413 | SCM_SYSCALL (ptr = (char *) malloc (size)); |
| 1414 | if (NULL != ptr) |
| 1415 | { |
| 1416 | scm_mallocated = nm; |
| 1417 | return ptr; |
| 1418 | } |
| 1419 | } |
| 1420 | |
| 1421 | scm_igc (what); |
| 1422 | nm = scm_mallocated + size; |
| 1423 | SCM_SYSCALL (ptr = (char *) malloc (size)); |
| 1424 | if (NULL != ptr) |
| 1425 | { |
| 1426 | scm_mallocated = nm; |
| 1427 | if (nm > scm_mtrigger - SCM_MTRIGGER_HYSTERESIS) { |
| 1428 | if (nm > scm_mtrigger) |
| 1429 | scm_mtrigger = nm + nm / 2; |
| 1430 | else |
| 1431 | scm_mtrigger += scm_mtrigger / 2; |
| 1432 | } |
| 1433 | return ptr; |
| 1434 | } |
| 1435 | goto malerr; |
| 1436 | } |
| 1437 | |
| 1438 | |
| 1439 | /* scm_must_realloc |
| 1440 | * is similar to scm_must_malloc. |
| 1441 | */ |
| 1442 | char * |
| 1443 | scm_must_realloc (where, olen, len, what) |
| 1444 | char *where; |
| 1445 | long olen; |
| 1446 | long len; |
| 1447 | char *what; |
| 1448 | { |
| 1449 | char *ptr; |
| 1450 | scm_sizet size = len; |
| 1451 | long nm = scm_mallocated + size - olen; |
| 1452 | if (len != size) |
| 1453 | ralerr: |
| 1454 | scm_wta (SCM_MAKINUM (len), (char *) SCM_NALLOC, what); |
| 1455 | if ((nm <= scm_mtrigger)) |
| 1456 | { |
| 1457 | SCM_SYSCALL (ptr = (char *) realloc (where, size)); |
| 1458 | if (NULL != ptr) |
| 1459 | { |
| 1460 | scm_mallocated = nm; |
| 1461 | return ptr; |
| 1462 | } |
| 1463 | } |
| 1464 | scm_igc (what); |
| 1465 | nm = scm_mallocated + size - olen; |
| 1466 | SCM_SYSCALL (ptr = (char *) realloc (where, size)); |
| 1467 | if (NULL != ptr) |
| 1468 | { |
| 1469 | scm_mallocated = nm; |
| 1470 | if (nm > scm_mtrigger - SCM_MTRIGGER_HYSTERESIS) { |
| 1471 | if (nm > scm_mtrigger) |
| 1472 | scm_mtrigger = nm + nm / 2; |
| 1473 | else |
| 1474 | scm_mtrigger += scm_mtrigger / 2; |
| 1475 | } |
| 1476 | return ptr; |
| 1477 | } |
| 1478 | goto ralerr; |
| 1479 | } |
| 1480 | |
| 1481 | void |
| 1482 | scm_must_free (obj) |
| 1483 | char *obj; |
| 1484 | { |
| 1485 | if (obj) |
| 1486 | free (obj); |
| 1487 | else |
| 1488 | scm_wta (SCM_INUM0, "already free", ""); |
| 1489 | } |
| 1490 | |
| 1491 | /* Announce that there has been some malloc done that will be freed |
| 1492 | * during gc. A typical use is for a smob that uses some malloced |
| 1493 | * memory but can not get it from scm_must_malloc (for whatever |
| 1494 | * reason). When a new object of this smob is created you call |
| 1495 | * scm_done_malloc with the size of the object. When your smob free |
| 1496 | * function is called, be sure to include this size in the return |
| 1497 | * value. */ |
| 1498 | |
| 1499 | void |
| 1500 | scm_done_malloc (size) |
| 1501 | long size; |
| 1502 | { |
| 1503 | scm_mallocated += size; |
| 1504 | |
| 1505 | if (scm_mallocated > scm_mtrigger) |
| 1506 | { |
| 1507 | scm_igc ("foreign mallocs"); |
| 1508 | if (scm_mallocated > scm_mtrigger - SCM_MTRIGGER_HYSTERESIS) |
| 1509 | { |
| 1510 | if (scm_mallocated > scm_mtrigger) |
| 1511 | scm_mtrigger = scm_mallocated + scm_mallocated / 2; |
| 1512 | else |
| 1513 | scm_mtrigger += scm_mtrigger / 2; |
| 1514 | } |
| 1515 | } |
| 1516 | } |
| 1517 | |
| 1518 | |
| 1519 | \f |
| 1520 | |
| 1521 | /* {Heap Segments} |
| 1522 | * |
| 1523 | * Each heap segment is an array of objects of a particular size. |
| 1524 | * Every segment has an associated (possibly shared) freelist. |
| 1525 | * A table of segment records is kept that records the upper and |
| 1526 | * lower extents of the segment; this is used during the conservative |
| 1527 | * phase of gc to identify probably gc roots (because they point |
| 1528 | * into valid segments at reasonable offsets). */ |
| 1529 | |
| 1530 | /* scm_expmem |
| 1531 | * is true if the first segment was smaller than INIT_HEAP_SEG. |
| 1532 | * If scm_expmem is set to one, subsequent segment allocations will |
| 1533 | * allocate segments of size SCM_EXPHEAP(scm_heap_size). |
| 1534 | */ |
| 1535 | int scm_expmem = 0; |
| 1536 | |
| 1537 | /* scm_heap_org |
| 1538 | * is the lowest base address of any heap segment. |
| 1539 | */ |
| 1540 | SCM_CELLPTR scm_heap_org; |
| 1541 | |
| 1542 | struct scm_heap_seg_data * scm_heap_table = 0; |
| 1543 | int scm_n_heap_segs = 0; |
| 1544 | |
| 1545 | /* scm_heap_size |
| 1546 | * is the total number of cells in heap segments. |
| 1547 | */ |
| 1548 | long scm_heap_size = 0; |
| 1549 | |
| 1550 | /* init_heap_seg |
| 1551 | * initializes a new heap segment and return the number of objects it contains. |
| 1552 | * |
| 1553 | * The segment origin, segment size in bytes, and the span of objects |
| 1554 | * in cells are input parameters. The freelist is both input and output. |
| 1555 | * |
| 1556 | * This function presume that the scm_heap_table has already been expanded |
| 1557 | * to accomodate a new segment record. |
| 1558 | */ |
| 1559 | |
| 1560 | |
| 1561 | static scm_sizet |
| 1562 | init_heap_seg (seg_org, size, ncells, freelistp) |
| 1563 | SCM_CELLPTR seg_org; |
| 1564 | scm_sizet size; |
| 1565 | int ncells; |
| 1566 | SCM *freelistp; |
| 1567 | { |
| 1568 | register SCM_CELLPTR ptr; |
| 1569 | #ifdef SCM_POINTERS_MUNGED |
| 1570 | register SCM scmptr; |
| 1571 | #else |
| 1572 | #undef scmptr |
| 1573 | #define scmptr ptr |
| 1574 | #endif |
| 1575 | SCM_CELLPTR seg_end; |
| 1576 | scm_sizet new_seg_index; |
| 1577 | scm_sizet n_new_objects; |
| 1578 | |
| 1579 | if (seg_org == NULL) |
| 1580 | return 0; |
| 1581 | |
| 1582 | ptr = seg_org; |
| 1583 | |
| 1584 | /* Compute the ceiling on valid object pointers w/in this segment. |
| 1585 | */ |
| 1586 | seg_end = CELL_DN ((char *) ptr + size); |
| 1587 | |
| 1588 | /* Find the right place and insert the segment record. |
| 1589 | * |
| 1590 | */ |
| 1591 | for (new_seg_index = 0; |
| 1592 | ( (new_seg_index < scm_n_heap_segs) |
| 1593 | && SCM_PTR_LE (scm_heap_table[new_seg_index].bounds[0], seg_org)); |
| 1594 | new_seg_index++) |
| 1595 | ; |
| 1596 | |
| 1597 | { |
| 1598 | int i; |
| 1599 | for (i = scm_n_heap_segs; i > new_seg_index; --i) |
| 1600 | scm_heap_table[i] = scm_heap_table[i - 1]; |
| 1601 | } |
| 1602 | |
| 1603 | ++scm_n_heap_segs; |
| 1604 | |
| 1605 | scm_heap_table[new_seg_index].valid = 0; |
| 1606 | scm_heap_table[new_seg_index].ncells = ncells; |
| 1607 | scm_heap_table[new_seg_index].freelistp = freelistp; |
| 1608 | scm_heap_table[new_seg_index].bounds[0] = (SCM_CELLPTR)ptr; |
| 1609 | scm_heap_table[new_seg_index].bounds[1] = (SCM_CELLPTR)seg_end; |
| 1610 | |
| 1611 | |
| 1612 | /* Compute the least valid object pointer w/in this segment |
| 1613 | */ |
| 1614 | ptr = CELL_UP (ptr); |
| 1615 | |
| 1616 | |
| 1617 | n_new_objects = seg_end - ptr; |
| 1618 | |
| 1619 | /* Prepend objects in this segment to the freelist. |
| 1620 | */ |
| 1621 | while (ptr < seg_end) |
| 1622 | { |
| 1623 | #ifdef SCM_POINTERS_MUNGED |
| 1624 | scmptr = PTR2SCM (ptr); |
| 1625 | #endif |
| 1626 | SCM_SETCAR (scmptr, (SCM) scm_tc_free_cell); |
| 1627 | SCM_SETCDR (scmptr, PTR2SCM (ptr + ncells)); |
| 1628 | ptr += ncells; |
| 1629 | } |
| 1630 | |
| 1631 | ptr -= ncells; |
| 1632 | |
| 1633 | /* Patch up the last freelist pointer in the segment |
| 1634 | * to join it to the input freelist. |
| 1635 | */ |
| 1636 | SCM_SETCDR (PTR2SCM (ptr), *freelistp); |
| 1637 | *freelistp = PTR2SCM (CELL_UP (seg_org)); |
| 1638 | |
| 1639 | scm_heap_size += (ncells * n_new_objects); |
| 1640 | return size; |
| 1641 | #ifdef scmptr |
| 1642 | #undef scmptr |
| 1643 | #endif |
| 1644 | } |
| 1645 | |
| 1646 | |
| 1647 | static void |
| 1648 | alloc_some_heap (ncells, freelistp) |
| 1649 | int ncells; |
| 1650 | SCM * freelistp; |
| 1651 | { |
| 1652 | struct scm_heap_seg_data * tmptable; |
| 1653 | SCM_CELLPTR ptr; |
| 1654 | scm_sizet len; |
| 1655 | |
| 1656 | /* Critical code sections (such as the garbage collector) |
| 1657 | * aren't supposed to add heap segments. |
| 1658 | */ |
| 1659 | if (scm_gc_heap_lock) |
| 1660 | scm_wta (SCM_UNDEFINED, "need larger initial", "heap"); |
| 1661 | |
| 1662 | /* Expand the heap tables to have room for the new segment. |
| 1663 | * Do not yet increment scm_n_heap_segs -- that is done by init_heap_seg |
| 1664 | * only if the allocation of the segment itself succeeds. |
| 1665 | */ |
| 1666 | len = (1 + scm_n_heap_segs) * sizeof (struct scm_heap_seg_data); |
| 1667 | |
| 1668 | SCM_SYSCALL (tmptable = ((struct scm_heap_seg_data *) |
| 1669 | realloc ((char *)scm_heap_table, len))); |
| 1670 | if (!tmptable) |
| 1671 | scm_wta (SCM_UNDEFINED, "could not grow", "hplims"); |
| 1672 | else |
| 1673 | scm_heap_table = tmptable; |
| 1674 | |
| 1675 | |
| 1676 | /* Pick a size for the new heap segment. |
| 1677 | * The rule for picking the size of a segment is explained in |
| 1678 | * gc.h |
| 1679 | */ |
| 1680 | if (scm_expmem) |
| 1681 | { |
| 1682 | len = (scm_sizet) (SCM_EXPHEAP (scm_heap_size) * sizeof (scm_cell)); |
| 1683 | if ((scm_sizet) (SCM_EXPHEAP (scm_heap_size) * sizeof (scm_cell)) != len) |
| 1684 | len = 0; |
| 1685 | } |
| 1686 | else |
| 1687 | len = SCM_HEAP_SEG_SIZE; |
| 1688 | |
| 1689 | { |
| 1690 | scm_sizet smallest; |
| 1691 | |
| 1692 | smallest = (ncells * sizeof (scm_cell)); |
| 1693 | if (len < smallest) |
| 1694 | len = (ncells * sizeof (scm_cell)); |
| 1695 | |
| 1696 | /* Allocate with decaying ambition. */ |
| 1697 | while ((len >= SCM_MIN_HEAP_SEG_SIZE) |
| 1698 | && (len >= smallest)) |
| 1699 | { |
| 1700 | SCM_SYSCALL (ptr = (SCM_CELLPTR) malloc (len)); |
| 1701 | if (ptr) |
| 1702 | { |
| 1703 | init_heap_seg (ptr, len, ncells, freelistp); |
| 1704 | return; |
| 1705 | } |
| 1706 | len /= 2; |
| 1707 | } |
| 1708 | } |
| 1709 | |
| 1710 | scm_wta (SCM_UNDEFINED, "could not grow", "heap"); |
| 1711 | } |
| 1712 | |
| 1713 | |
| 1714 | |
| 1715 | SCM_PROC (s_unhash_name, "unhash-name", 1, 0, 0, scm_unhash_name); |
| 1716 | SCM |
| 1717 | scm_unhash_name (name) |
| 1718 | SCM name; |
| 1719 | { |
| 1720 | int x; |
| 1721 | int bound; |
| 1722 | SCM_ASSERT (SCM_NIMP (name) && SCM_SYMBOLP (name), name, SCM_ARG1, s_unhash_name); |
| 1723 | SCM_DEFER_INTS; |
| 1724 | bound = scm_n_heap_segs; |
| 1725 | for (x = 0; x < bound; ++x) |
| 1726 | { |
| 1727 | SCM_CELLPTR p; |
| 1728 | SCM_CELLPTR pbound; |
| 1729 | p = (SCM_CELLPTR)scm_heap_table[x].bounds[0]; |
| 1730 | pbound = (SCM_CELLPTR)scm_heap_table[x].bounds[1]; |
| 1731 | while (p < pbound) |
| 1732 | { |
| 1733 | SCM incar; |
| 1734 | incar = p->car; |
| 1735 | if (1 == (7 & (int)incar)) |
| 1736 | { |
| 1737 | --incar; |
| 1738 | if ( ((name == SCM_BOOL_T) || (SCM_CAR (incar) == name)) |
| 1739 | && (SCM_CDR (incar) != 0) |
| 1740 | && (SCM_CDR (incar) != 1)) |
| 1741 | { |
| 1742 | p->car = name; |
| 1743 | } |
| 1744 | } |
| 1745 | ++p; |
| 1746 | } |
| 1747 | } |
| 1748 | SCM_ALLOW_INTS; |
| 1749 | return name; |
| 1750 | } |
| 1751 | |
| 1752 | |
| 1753 | \f |
| 1754 | /* {GC Protection Helper Functions} |
| 1755 | */ |
| 1756 | |
| 1757 | |
| 1758 | void |
| 1759 | scm_remember (ptr) |
| 1760 | SCM * ptr; |
| 1761 | {} |
| 1762 | |
| 1763 | |
| 1764 | #ifdef __STDC__ |
| 1765 | SCM |
| 1766 | scm_return_first (SCM elt, ...) |
| 1767 | #else |
| 1768 | SCM |
| 1769 | scm_return_first (elt, va_alist) |
| 1770 | SCM elt; |
| 1771 | va_dcl |
| 1772 | #endif |
| 1773 | { |
| 1774 | return elt; |
| 1775 | } |
| 1776 | |
| 1777 | |
| 1778 | SCM |
| 1779 | scm_permanent_object (obj) |
| 1780 | SCM obj; |
| 1781 | { |
| 1782 | SCM_REDEFER_INTS; |
| 1783 | scm_permobjs = scm_cons (obj, scm_permobjs); |
| 1784 | SCM_REALLOW_INTS; |
| 1785 | return obj; |
| 1786 | } |
| 1787 | |
| 1788 | |
| 1789 | /* Protect OBJ from the garbage collector. OBJ will not be freed, |
| 1790 | even if all other references are dropped, until someone applies |
| 1791 | scm_unprotect_object to it. This function returns OBJ. |
| 1792 | |
| 1793 | Note that calls to scm_protect_object do not nest. You can call |
| 1794 | scm_protect_object any number of times on a given object, and the |
| 1795 | next call to scm_unprotect_object will unprotect it completely. |
| 1796 | |
| 1797 | Basically, scm_protect_object and scm_unprotect_object just |
| 1798 | maintain a list of references to things. Since the GC knows about |
| 1799 | this list, all objects it mentions stay alive. scm_protect_object |
| 1800 | adds its argument to the list; scm_unprotect_object remove its |
| 1801 | argument from the list. */ |
| 1802 | SCM |
| 1803 | scm_protect_object (obj) |
| 1804 | SCM obj; |
| 1805 | { |
| 1806 | /* This function really should use address hashing tables, but I |
| 1807 | don't know how to use them yet. For now we just use a list. */ |
| 1808 | scm_protects = scm_cons (obj, scm_protects); |
| 1809 | |
| 1810 | return obj; |
| 1811 | } |
| 1812 | |
| 1813 | |
| 1814 | /* Remove any protection for OBJ established by a prior call to |
| 1815 | scm_protect_obj. This function returns OBJ. |
| 1816 | |
| 1817 | See scm_protect_obj for more information. */ |
| 1818 | SCM |
| 1819 | scm_unprotect_object (obj) |
| 1820 | SCM obj; |
| 1821 | { |
| 1822 | scm_protects = scm_delq_x (obj, scm_protects); |
| 1823 | |
| 1824 | return obj; |
| 1825 | } |
| 1826 | |
| 1827 | |
| 1828 | \f |
| 1829 | int |
| 1830 | scm_init_storage (init_heap_size) |
| 1831 | long init_heap_size; |
| 1832 | { |
| 1833 | scm_sizet j; |
| 1834 | |
| 1835 | j = SCM_NUM_PROTECTS; |
| 1836 | while (j) |
| 1837 | scm_sys_protects[--j] = SCM_BOOL_F; |
| 1838 | scm_block_gc = 1; |
| 1839 | scm_freelist = SCM_EOL; |
| 1840 | scm_expmem = 0; |
| 1841 | |
| 1842 | j = SCM_HEAP_SEG_SIZE; |
| 1843 | scm_mtrigger = SCM_INIT_MALLOC_LIMIT; |
| 1844 | scm_heap_table = ((struct scm_heap_seg_data *) |
| 1845 | scm_must_malloc (sizeof (struct scm_heap_seg_data), "hplims")); |
| 1846 | if (0L == init_heap_size) |
| 1847 | init_heap_size = SCM_INIT_HEAP_SIZE; |
| 1848 | j = init_heap_size; |
| 1849 | if ((init_heap_size != j) |
| 1850 | || !init_heap_seg ((SCM_CELLPTR) malloc (j), j, 1, &scm_freelist)) |
| 1851 | { |
| 1852 | j = SCM_HEAP_SEG_SIZE; |
| 1853 | if (!init_heap_seg ((SCM_CELLPTR) malloc (j), j, 1, &scm_freelist)) |
| 1854 | return 1; |
| 1855 | } |
| 1856 | else |
| 1857 | scm_expmem = 1; |
| 1858 | scm_heap_org = CELL_UP (scm_heap_table[0].bounds[0]); |
| 1859 | /* scm_hplims[0] can change. do not remove scm_heap_org */ |
| 1860 | if (!(scm_weak_vectors = (SCM *) malloc ((scm_weak_size = 32) * sizeof(SCM *)))) |
| 1861 | return 1; |
| 1862 | |
| 1863 | /* Initialise the list of ports. */ |
| 1864 | scm_port_table = (struct scm_port_table **) malloc ((long) (sizeof (struct scm_port_table) |
| 1865 | * scm_port_table_room)); |
| 1866 | if (!scm_port_table) |
| 1867 | return 1; |
| 1868 | |
| 1869 | |
| 1870 | scm_undefineds = scm_cons (SCM_UNDEFINED, SCM_EOL); |
| 1871 | SCM_SETCDR (scm_undefineds, scm_undefineds); |
| 1872 | |
| 1873 | scm_listofnull = scm_cons (SCM_EOL, SCM_EOL); |
| 1874 | scm_nullstr = scm_makstr (0L, 0); |
| 1875 | scm_nullvect = scm_make_vector (SCM_INUM0, SCM_UNDEFINED, SCM_UNDEFINED); |
| 1876 | scm_symhash = scm_make_vector ((SCM) SCM_MAKINUM (scm_symhash_dim), SCM_EOL, SCM_UNDEFINED); |
| 1877 | scm_weak_symhash = scm_make_weak_key_hash_table ((SCM) SCM_MAKINUM (scm_symhash_dim)); |
| 1878 | scm_symhash_vars = scm_make_vector ((SCM) SCM_MAKINUM (scm_symhash_dim), SCM_EOL, SCM_UNDEFINED); |
| 1879 | scm_stand_in_procs = SCM_EOL; |
| 1880 | scm_permobjs = SCM_EOL; |
| 1881 | scm_protects = SCM_EOL; |
| 1882 | scm_asyncs = SCM_EOL; |
| 1883 | scm_sysintern ("most-positive-fixnum", (SCM) SCM_MAKINUM (SCM_MOST_POSITIVE_FIXNUM)); |
| 1884 | scm_sysintern ("most-negative-fixnum", (SCM) SCM_MAKINUM (SCM_MOST_NEGATIVE_FIXNUM)); |
| 1885 | #ifdef SCM_BIGDIG |
| 1886 | scm_sysintern ("bignum-radix", SCM_MAKINUM (SCM_BIGRAD)); |
| 1887 | #endif |
| 1888 | return 0; |
| 1889 | } |
| 1890 | \f |
| 1891 | |
| 1892 | void |
| 1893 | scm_init_gc () |
| 1894 | { |
| 1895 | #include "gc.x" |
| 1896 | } |