1 /* Copyright (C) 1995,1996,1997,1998,1999,2000,2001 Free Software Foundation, Inc.
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)
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.
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
18 * As a special exception, the Free Software Foundation gives permission
19 * for additional uses of the text contained in its release of GUILE.
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.
27 * This exception does not however invalidate any other reasons why
28 * the executable file might be covered by the GNU General Public License.
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.
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. */
42 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
43 gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
45 /* #define DEBUGINFO */
47 /* SECTION: This code is compiled once.
50 #ifndef MARK_DEPENDENCIES
57 #include "libguile/_scm.h"
58 #include "libguile/eval.h"
59 #include "libguile/stime.h"
60 #include "libguile/stackchk.h"
61 #include "libguile/struct.h"
62 #include "libguile/smob.h"
63 #include "libguile/unif.h"
64 #include "libguile/async.h"
65 #include "libguile/ports.h"
66 #include "libguile/root.h"
67 #include "libguile/strings.h"
68 #include "libguile/vectors.h"
69 #include "libguile/weaks.h"
70 #include "libguile/hashtab.h"
71 #include "libguile/tags.h"
73 #include "libguile/validate.h"
74 #include "libguile/gc.h"
76 #ifdef GUILE_DEBUG_MALLOC
77 #include "libguile/debug-malloc.h"
90 #define var_start(x, y) va_start(x, y)
93 #define var_start(x, y) va_start(x)
98 unsigned int scm_gc_running_p
= 0;
102 #if (SCM_DEBUG_CELL_ACCESSES == 1)
104 scm_bits_t scm_tc16_allocated
;
106 /* Set this to != 0 if every cell that is accessed shall be checked:
108 unsigned int scm_debug_cell_accesses_p
= 1;
111 /* Assert that the given object is a valid reference to a valid cell. This
112 * test involves to determine whether the object is a cell pointer, whether
113 * this pointer actually points into a heap segment and whether the cell
114 * pointed to is not a free cell.
117 scm_assert_cell_valid (SCM cell
)
119 static unsigned int already_running
= 0;
121 if (scm_debug_cell_accesses_p
&& !already_running
)
123 already_running
= 1; /* set to avoid recursion */
125 if (!scm_cellp (cell
))
127 fprintf (stderr
, "scm_assert_cell_valid: Not a cell object: %lx\n", SCM_UNPACK (cell
));
130 else if (!scm_gc_running_p
)
132 /* Dirk::FIXME:: During garbage collection there occur references to
133 free cells. This is allright during conservative marking, but
134 should not happen otherwise (I think). The case of free cells
135 accessed during conservative marking is handled in function
136 scm_mark_locations. However, there still occur accesses to free
137 cells during gc. I don't understand why this happens. If it is
138 a bug and gets fixed, the following test should also work while
141 if (SCM_FREE_CELL_P (cell
))
143 fprintf (stderr
, "scm_assert_cell_valid: Accessing free cell: %lx\n", SCM_UNPACK (cell
));
147 already_running
= 0; /* re-enable */
152 SCM_DEFINE (scm_set_debug_cell_accesses_x
, "set-debug-cell-accesses!", 1, 0, 0,
154 "If FLAG is #f, cell access checking is disabled.\n"
155 "If FLAG is #t, cell access checking is enabled.\n"
156 "This procedure only exists because the compile-time flag\n"
157 "SCM_DEBUG_CELL_ACCESSES was set to 1.\n")
158 #define FUNC_NAME s_scm_set_debug_cell_accesses_x
160 if (SCM_FALSEP (flag
)) {
161 scm_debug_cell_accesses_p
= 0;
162 } else if (SCM_EQ_P (flag
, SCM_BOOL_T
)) {
163 scm_debug_cell_accesses_p
= 1;
165 SCM_WRONG_TYPE_ARG (1, flag
);
167 return SCM_UNSPECIFIED
;
171 #endif /* SCM_DEBUG_CELL_ACCESSES == 1 */
175 /* {heap tuning parameters}
177 * These are parameters for controlling memory allocation. The heap
178 * is the area out of which scm_cons, and object headers are allocated.
180 * Each heap cell is 8 bytes on a 32 bit machine and 16 bytes on a
181 * 64 bit machine. The units of the _SIZE parameters are bytes.
182 * Cons pairs and object headers occupy one heap cell.
184 * SCM_INIT_HEAP_SIZE is the initial size of heap. If this much heap is
185 * allocated initially the heap will grow by half its current size
186 * each subsequent time more heap is needed.
188 * If SCM_INIT_HEAP_SIZE heap cannot be allocated initially, SCM_HEAP_SEG_SIZE
189 * will be used, and the heap will grow by SCM_HEAP_SEG_SIZE when more
190 * heap is needed. SCM_HEAP_SEG_SIZE must fit into type scm_sizet. This code
191 * is in scm_init_storage() and alloc_some_heap() in sys.c
193 * If SCM_INIT_HEAP_SIZE can be allocated initially, the heap will grow by
194 * SCM_EXPHEAP(scm_heap_size) when more heap is needed.
196 * SCM_MIN_HEAP_SEG_SIZE is minimum size of heap to accept when more heap
199 * INIT_MALLOC_LIMIT is the initial amount of malloc usage which will
202 * SCM_MTRIGGER_HYSTERESIS is the amount of malloc storage that must be
203 * reclaimed by a GC triggered by must_malloc. If less than this is
204 * reclaimed, the trigger threshold is raised. [I don't know what a
205 * good value is. I arbitrarily chose 1/10 of the INIT_MALLOC_LIMIT to
206 * work around a oscillation that caused almost constant GC.]
210 * Heap size 45000 and 40% min yield gives quick startup and no extra
211 * heap allocation. Having higher values on min yield may lead to
212 * large heaps, especially if code behaviour is varying its
213 * maximum consumption between different freelists.
216 #define SCM_DATA_CELLS2CARDS(n) (((n) + SCM_GC_CARD_N_DATA_CELLS - 1) / SCM_GC_CARD_N_DATA_CELLS)
217 #define SCM_CARDS_PER_CLUSTER SCM_DATA_CELLS2CARDS (2000L)
218 #define SCM_CLUSTER_SIZE_1 (SCM_CARDS_PER_CLUSTER * SCM_GC_CARD_N_DATA_CELLS)
219 int scm_default_init_heap_size_1
= (((SCM_DATA_CELLS2CARDS (45000L) + SCM_CARDS_PER_CLUSTER
- 1)
220 / SCM_CARDS_PER_CLUSTER
) * SCM_GC_CARD_SIZE
);
221 int scm_default_min_yield_1
= 40;
223 #define SCM_CLUSTER_SIZE_2 (SCM_CARDS_PER_CLUSTER * (SCM_GC_CARD_N_DATA_CELLS / 2))
224 int scm_default_init_heap_size_2
= (((SCM_DATA_CELLS2CARDS (2500L * 2) + SCM_CARDS_PER_CLUSTER
- 1)
225 / SCM_CARDS_PER_CLUSTER
) * SCM_GC_CARD_SIZE
);
226 /* The following value may seem large, but note that if we get to GC at
227 * all, this means that we have a numerically intensive application
229 int scm_default_min_yield_2
= 40;
231 int scm_default_max_segment_size
= 2097000L;/* a little less (adm) than 2 Mb */
233 #define SCM_MIN_HEAP_SEG_SIZE (8 * SCM_GC_CARD_SIZE)
235 # define SCM_HEAP_SEG_SIZE 32768L
238 # define SCM_HEAP_SEG_SIZE (7000L * sizeof (scm_cell))
240 # define SCM_HEAP_SEG_SIZE (16384L * sizeof (scm_cell))
243 /* Make heap grow with factor 1.5 */
244 #define SCM_EXPHEAP(scm_heap_size) (scm_heap_size / 2)
245 #define SCM_INIT_MALLOC_LIMIT 100000
246 #define SCM_MTRIGGER_HYSTERESIS (SCM_INIT_MALLOC_LIMIT/10)
248 /* CELL_UP and CELL_DN are used by scm_init_heap_seg to find (scm_cell * span)
249 aligned inner bounds for allocated storage */
252 /*in 386 protected mode we must only adjust the offset */
253 # define CELL_UP(p, span) MK_FP(FP_SEG(p), ~(8*(span)-1)&(FP_OFF(p)+8*(span)-1))
254 # define CELL_DN(p, span) MK_FP(FP_SEG(p), ~(8*(span)-1)&FP_OFF(p))
257 # define CELL_UP(p, span) (SCM_CELLPTR)(~(span) & ((long)(p)+(span)))
258 # define CELL_DN(p, span) (SCM_CELLPTR)(~(span) & (long)(p))
260 # define CELL_UP(p, span) (SCM_CELLPTR)(~(sizeof(scm_cell)*(span)-1L) & ((long)(p)+sizeof(scm_cell)*(span)-1L))
261 # define CELL_DN(p, span) (SCM_CELLPTR)(~(sizeof(scm_cell)*(span)-1L) & (long)(p))
265 #define DOUBLECELL_ALIGNED_P(x) (((2 * sizeof (scm_cell) - 1) & SCM_UNPACK (x)) == 0)
267 #define ALIGNMENT_SLACK(freelist) (SCM_GC_CARD_SIZE - 1)
268 #define CLUSTER_SIZE_IN_BYTES(freelist) \
269 (((freelist)->cluster_size / (SCM_GC_CARD_N_DATA_CELLS / (freelist)->span)) * SCM_GC_CARD_SIZE)
275 typedef struct scm_freelist_t
{
276 /* collected cells */
278 /* number of cells left to collect before cluster is full */
279 unsigned int left_to_collect
;
280 /* number of clusters which have been allocated */
281 unsigned int clusters_allocated
;
282 /* a list of freelists, each of size cluster_size,
283 * except the last one which may be shorter
287 /* this is the number of objects in each cluster, including the spine cell */
289 /* indicates that we should grow heap instead of GC:ing
292 /* minimum yield on this list in order not to grow the heap
295 /* defines min_yield as percent of total heap size
297 int min_yield_fraction
;
298 /* number of cells per object on this list */
300 /* number of collected cells during last GC */
302 /* number of collected cells during penultimate GC */
304 /* total number of cells in heap segments
305 * belonging to this list.
310 SCM scm_freelist
= SCM_EOL
;
311 scm_freelist_t scm_master_freelist
= {
312 SCM_EOL
, 0, 0, SCM_EOL
, 0, SCM_CLUSTER_SIZE_1
, 0, 0, 0, 1, 0, 0
314 SCM scm_freelist2
= SCM_EOL
;
315 scm_freelist_t scm_master_freelist2
= {
316 SCM_EOL
, 0, 0, SCM_EOL
, 0, SCM_CLUSTER_SIZE_2
, 0, 0, 0, 2, 0, 0
320 * is the number of bytes of must_malloc allocation needed to trigger gc.
322 unsigned long scm_mtrigger
;
325 * If set, don't expand the heap. Set only during gc, during which no allocation
326 * is supposed to take place anyway.
328 int scm_gc_heap_lock
= 0;
331 * Don't pause for collection if this is set -- just
334 int scm_block_gc
= 1;
336 /* During collection, this accumulates objects holding
339 SCM scm_weak_vectors
;
341 /* During collection, this accumulates structures which are to be freed.
343 SCM scm_structs_to_free
;
345 /* GC Statistics Keeping
347 unsigned long scm_cells_allocated
= 0;
348 long scm_mallocated
= 0;
349 unsigned long scm_gc_cells_collected
;
350 unsigned long scm_gc_yield
;
351 static unsigned long scm_gc_yield_1
= 0; /* previous GC yield */
352 unsigned long scm_gc_malloc_collected
;
353 unsigned long scm_gc_ports_collected
;
354 unsigned long scm_gc_time_taken
= 0;
355 static unsigned long t_before_gc
;
356 static unsigned long t_before_sweep
;
357 unsigned long scm_gc_mark_time_taken
= 0;
358 unsigned long scm_gc_sweep_time_taken
= 0;
359 unsigned long scm_gc_times
= 0;
360 unsigned long scm_gc_cells_swept
= 0;
361 double scm_gc_cells_marked_acc
= 0.;
362 double scm_gc_cells_swept_acc
= 0.;
364 SCM_SYMBOL (sym_cells_allocated
, "cells-allocated");
365 SCM_SYMBOL (sym_heap_size
, "cell-heap-size");
366 SCM_SYMBOL (sym_mallocated
, "bytes-malloced");
367 SCM_SYMBOL (sym_mtrigger
, "gc-malloc-threshold");
368 SCM_SYMBOL (sym_heap_segments
, "cell-heap-segments");
369 SCM_SYMBOL (sym_gc_time_taken
, "gc-time-taken");
370 SCM_SYMBOL (sym_gc_mark_time_taken
, "gc-mark-time-taken");
371 SCM_SYMBOL (sym_gc_sweep_time_taken
, "gc-sweep-time-taken");
372 SCM_SYMBOL (sym_times
, "gc-times");
373 SCM_SYMBOL (sym_cells_marked
, "cells-marked");
374 SCM_SYMBOL (sym_cells_swept
, "cells-swept");
376 typedef struct scm_heap_seg_data_t
378 /* lower and upper bounds of the segment */
379 SCM_CELLPTR bounds
[2];
381 /* address of the head-of-freelist pointer for this segment's cells.
382 All segments usually point to the same one, scm_freelist. */
383 scm_freelist_t
*freelist
;
385 /* number of cells per object in this segment */
387 } scm_heap_seg_data_t
;
391 static scm_sizet
init_heap_seg (SCM_CELLPTR
, scm_sizet
, scm_freelist_t
*);
393 typedef enum { return_on_error
, abort_on_error
} policy_on_error
;
394 static void alloc_some_heap (scm_freelist_t
*, policy_on_error
);
397 #define SCM_HEAP_SIZE \
398 (scm_master_freelist.heap_size + scm_master_freelist2.heap_size)
399 #define SCM_MAX(A, B) ((A) > (B) ? (A) : (B))
401 #define BVEC_GROW_SIZE 256
402 #define BVEC_GROW_SIZE_IN_LIMBS (SCM_GC_CARD_BVEC_SIZE_IN_LIMBS * BVEC_GROW_SIZE)
403 #define BVEC_GROW_SIZE_IN_BYTES (BVEC_GROW_SIZE_IN_LIMBS * sizeof (scm_c_bvec_limb_t))
405 /* mark space allocation */
407 typedef struct scm_mark_space_t
409 scm_c_bvec_limb_t
*bvec_space
;
410 struct scm_mark_space_t
*next
;
413 static scm_mark_space_t
*current_mark_space
;
414 static scm_mark_space_t
**mark_space_ptr
;
415 static int current_mark_space_offset
;
416 static scm_mark_space_t
*mark_space_head
;
418 static scm_c_bvec_limb_t
*
420 #define FUNC_NAME "get_bvec"
422 scm_c_bvec_limb_t
*res
;
424 if (!current_mark_space
)
426 SCM_SYSCALL (current_mark_space
= (scm_mark_space_t
*) malloc (sizeof (scm_mark_space_t
)));
427 if (!current_mark_space
)
428 SCM_MISC_ERROR ("could not grow heap", SCM_EOL
);
430 current_mark_space
->bvec_space
= NULL
;
431 current_mark_space
->next
= NULL
;
433 *mark_space_ptr
= current_mark_space
;
434 mark_space_ptr
= &(current_mark_space
->next
);
439 if (!(current_mark_space
->bvec_space
))
441 SCM_SYSCALL (current_mark_space
->bvec_space
=
442 (scm_c_bvec_limb_t
*) calloc (BVEC_GROW_SIZE_IN_BYTES
, 1));
443 if (!(current_mark_space
->bvec_space
))
444 SCM_MISC_ERROR ("could not grow heap", SCM_EOL
);
446 current_mark_space_offset
= 0;
451 if (current_mark_space_offset
== BVEC_GROW_SIZE_IN_LIMBS
)
453 current_mark_space
= NULL
;
458 res
= current_mark_space
->bvec_space
+ current_mark_space_offset
;
459 current_mark_space_offset
+= SCM_GC_CARD_BVEC_SIZE_IN_LIMBS
;
469 scm_mark_space_t
*ms
;
471 for (ms
= mark_space_head
; ms
; ms
= ms
->next
)
472 memset (ms
->bvec_space
, 0, BVEC_GROW_SIZE_IN_BYTES
);
477 /* Debugging functions. */
479 #if defined (GUILE_DEBUG) || defined (GUILE_DEBUG_FREELIST)
481 /* Return the number of the heap segment containing CELL. */
487 for (i
= 0; i
< scm_n_heap_segs
; i
++)
488 if (SCM_PTR_LE (scm_heap_table
[i
].bounds
[0], SCM2PTR (cell
))
489 && SCM_PTR_GT (scm_heap_table
[i
].bounds
[1], SCM2PTR (cell
)))
491 fprintf (stderr
, "which_seg: can't find segment containing cell %lx\n",
498 map_free_list (scm_freelist_t
*master
, SCM freelist
)
500 int last_seg
= -1, count
= 0;
503 for (f
= freelist
; !SCM_NULLP (f
); f
= SCM_FREE_CELL_CDR (f
))
505 int this_seg
= which_seg (f
);
507 if (this_seg
!= last_seg
)
510 fprintf (stderr
, " %5d %d-cells in segment %d\n",
511 count
, master
->span
, last_seg
);
518 fprintf (stderr
, " %5d %d-cells in segment %d\n",
519 count
, master
->span
, last_seg
);
522 SCM_DEFINE (scm_map_free_list
, "map-free-list", 0, 0, 0,
524 "Print debugging information about the free-list.\n"
525 "@code{map-free-list} is only included in\n"
526 "@code{--enable-guile-debug} builds of Guile.")
527 #define FUNC_NAME s_scm_map_free_list
530 fprintf (stderr
, "%d segments total (%d:%d",
532 scm_heap_table
[0].span
,
533 scm_heap_table
[0].bounds
[1] - scm_heap_table
[0].bounds
[0]);
534 for (i
= 1; i
< scm_n_heap_segs
; i
++)
535 fprintf (stderr
, ", %d:%d",
536 scm_heap_table
[i
].span
,
537 scm_heap_table
[i
].bounds
[1] - scm_heap_table
[i
].bounds
[0]);
538 fprintf (stderr
, ")\n");
539 map_free_list (&scm_master_freelist
, scm_freelist
);
540 map_free_list (&scm_master_freelist2
, scm_freelist2
);
543 return SCM_UNSPECIFIED
;
547 static int last_cluster
;
548 static int last_size
;
551 free_list_length (char *title
, int i
, SCM freelist
)
555 for (ls
= freelist
; !SCM_NULLP (ls
); ls
= SCM_FREE_CELL_CDR (ls
))
556 if (SCM_FREE_CELL_P (ls
))
560 fprintf (stderr
, "bad cell in %s at position %d\n", title
, n
);
567 if (last_cluster
== i
- 1)
568 fprintf (stderr
, "\t%d\n", last_size
);
570 fprintf (stderr
, "-%d\t%d\n", i
- 1, last_size
);
573 fprintf (stderr
, "%s %d", title
, i
);
575 fprintf (stderr
, "%s\t%d\n", title
, n
);
583 free_list_lengths (char *title
, scm_freelist_t
*master
, SCM freelist
)
586 int i
= 0, len
, n
= 0;
587 fprintf (stderr
, "%s\n\n", title
);
588 n
+= free_list_length ("free list", -1, freelist
);
589 for (clusters
= master
->clusters
;
590 SCM_NNULLP (clusters
);
591 clusters
= SCM_CDR (clusters
))
593 len
= free_list_length ("cluster", i
++, SCM_CAR (clusters
));
596 if (last_cluster
== i
- 1)
597 fprintf (stderr
, "\t%d\n", last_size
);
599 fprintf (stderr
, "-%d\t%d\n", i
- 1, last_size
);
600 fprintf (stderr
, "\ntotal %d objects\n\n", n
);
603 SCM_DEFINE (scm_free_list_length
, "free-list-length", 0, 0, 0,
605 "Print debugging information about the free-list.\n"
606 "@code{free-list-length} is only included in\n"
607 "@code{--enable-guile-debug} builds of Guile.")
608 #define FUNC_NAME s_scm_free_list_length
610 free_list_lengths ("1-cells", &scm_master_freelist
, scm_freelist
);
611 free_list_lengths ("2-cells", &scm_master_freelist2
, scm_freelist2
);
612 return SCM_UNSPECIFIED
;
618 #ifdef GUILE_DEBUG_FREELIST
620 /* Non-zero if freelist debugging is in effect. Set this via
621 `gc-set-debug-check-freelist!'. */
622 static int scm_debug_check_freelist
= 0;
624 /* Number of calls to SCM_NEWCELL since startup. */
625 static unsigned long scm_newcell_count
;
626 static unsigned long scm_newcell2_count
;
628 /* Search freelist for anything that isn't marked as a free cell.
629 Abort if we find something. */
631 scm_check_freelist (SCM freelist
)
636 for (f
= freelist
; !SCM_NULLP (f
); f
= SCM_FREE_CELL_CDR (f
), i
++)
637 if (!SCM_FREE_CELL_P (f
))
639 fprintf (stderr
, "Bad cell in freelist on newcell %lu: %d'th elt\n",
640 scm_newcell_count
, i
);
645 SCM_DEFINE (scm_gc_set_debug_check_freelist_x
, "gc-set-debug-check-freelist!", 1, 0, 0,
647 "If FLAG is #t, check the freelist for consistency on each cell allocation.\n"
648 "This procedure only exists because the GUILE_DEBUG_FREELIST \n"
649 "compile-time flag was selected.\n")
650 #define FUNC_NAME s_scm_gc_set_debug_check_freelist_x
652 /* [cmm] I did a double-take when I read this code the first time.
654 SCM_VALIDATE_BOOL_COPY (1, flag
, scm_debug_check_freelist
);
655 return SCM_UNSPECIFIED
;
661 scm_debug_newcell (void)
666 if (scm_debug_check_freelist
)
668 scm_check_freelist (scm_freelist
);
672 /* The rest of this is supposed to be identical to the SCM_NEWCELL
674 if (SCM_NULLP (scm_freelist
))
675 new = scm_gc_for_newcell (&scm_master_freelist
, &scm_freelist
);
679 scm_freelist
= SCM_FREE_CELL_CDR (scm_freelist
);
686 scm_debug_newcell2 (void)
690 scm_newcell2_count
++;
691 if (scm_debug_check_freelist
)
693 scm_check_freelist (scm_freelist2
);
697 /* The rest of this is supposed to be identical to the SCM_NEWCELL
699 if (SCM_NULLP (scm_freelist2
))
700 new = scm_gc_for_newcell (&scm_master_freelist2
, &scm_freelist2
);
704 scm_freelist2
= SCM_FREE_CELL_CDR (scm_freelist2
);
710 #endif /* GUILE_DEBUG_FREELIST */
715 master_cells_allocated (scm_freelist_t
*master
)
717 /* the '- 1' below is to ignore the cluster spine cells. */
718 int objects
= master
->clusters_allocated
* (master
->cluster_size
- 1);
719 if (SCM_NULLP (master
->clusters
))
720 objects
-= master
->left_to_collect
;
721 return master
->span
* objects
;
725 freelist_length (SCM freelist
)
728 for (n
= 0; !SCM_NULLP (freelist
); freelist
= SCM_FREE_CELL_CDR (freelist
))
734 compute_cells_allocated ()
736 return (scm_cells_allocated
737 + master_cells_allocated (&scm_master_freelist
)
738 + master_cells_allocated (&scm_master_freelist2
)
739 - scm_master_freelist
.span
* freelist_length (scm_freelist
)
740 - scm_master_freelist2
.span
* freelist_length (scm_freelist2
));
743 /* {Scheme Interface to GC}
746 SCM_DEFINE (scm_gc_stats
, "gc-stats", 0, 0, 0,
748 "Returns an association list of statistics about Guile's current use of storage. ")
749 #define FUNC_NAME s_scm_gc_stats
754 long int local_scm_mtrigger
;
755 long int local_scm_mallocated
;
756 long int local_scm_heap_size
;
757 long int local_scm_cells_allocated
;
758 long int local_scm_gc_time_taken
;
759 long int local_scm_gc_times
;
760 long int local_scm_gc_mark_time_taken
;
761 long int local_scm_gc_sweep_time_taken
;
762 double local_scm_gc_cells_swept
;
763 double local_scm_gc_cells_marked
;
773 for (i
= scm_n_heap_segs
; i
--; )
774 heap_segs
= scm_cons (scm_cons (scm_ulong2num ((unsigned long)scm_heap_table
[i
].bounds
[1]),
775 scm_ulong2num ((unsigned long)scm_heap_table
[i
].bounds
[0])),
777 if (scm_n_heap_segs
!= n
)
782 /* Below, we cons to produce the resulting list. We want a snapshot of
783 * the heap situation before consing.
785 local_scm_mtrigger
= scm_mtrigger
;
786 local_scm_mallocated
= scm_mallocated
;
787 local_scm_heap_size
= SCM_HEAP_SIZE
;
788 local_scm_cells_allocated
= compute_cells_allocated ();
789 local_scm_gc_time_taken
= scm_gc_time_taken
;
790 local_scm_gc_mark_time_taken
= scm_gc_mark_time_taken
;
791 local_scm_gc_sweep_time_taken
= scm_gc_sweep_time_taken
;
792 local_scm_gc_times
= scm_gc_times
;
793 local_scm_gc_cells_swept
= scm_gc_cells_swept_acc
;
794 local_scm_gc_cells_marked
= scm_gc_cells_marked_acc
;
796 answer
= scm_listify (scm_cons (sym_gc_time_taken
, scm_ulong2num (local_scm_gc_time_taken
)),
797 scm_cons (sym_cells_allocated
, scm_ulong2num (local_scm_cells_allocated
)),
798 scm_cons (sym_heap_size
, scm_ulong2num (local_scm_heap_size
)),
799 scm_cons (sym_mallocated
, scm_ulong2num (local_scm_mallocated
)),
800 scm_cons (sym_mtrigger
, scm_ulong2num (local_scm_mtrigger
)),
801 scm_cons (sym_times
, scm_ulong2num (local_scm_gc_times
)),
802 scm_cons (sym_gc_mark_time_taken
, scm_ulong2num (local_scm_gc_mark_time_taken
)),
803 scm_cons (sym_gc_sweep_time_taken
, scm_ulong2num (local_scm_gc_sweep_time_taken
)),
804 scm_cons (sym_cells_marked
, scm_dbl2big (local_scm_gc_cells_marked
)),
805 scm_cons (sym_cells_swept
, scm_dbl2big (local_scm_gc_cells_swept
)),
806 scm_cons (sym_heap_segments
, heap_segs
),
815 gc_start_stats (const char *what
)
817 t_before_gc
= scm_c_get_internal_run_time ();
818 scm_gc_cells_swept
= 0;
819 scm_gc_cells_collected
= 0;
820 scm_gc_yield_1
= scm_gc_yield
;
821 scm_gc_yield
= (scm_cells_allocated
822 + master_cells_allocated (&scm_master_freelist
)
823 + master_cells_allocated (&scm_master_freelist2
));
824 scm_gc_malloc_collected
= 0;
825 scm_gc_ports_collected
= 0;
832 unsigned long t
= scm_c_get_internal_run_time ();
833 scm_gc_time_taken
+= (t
- t_before_gc
);
834 scm_gc_sweep_time_taken
+= (t
- t_before_sweep
);
837 scm_gc_cells_marked_acc
+= scm_gc_cells_swept
- scm_gc_cells_collected
;
838 scm_gc_cells_swept_acc
+= scm_gc_cells_swept
;
842 SCM_DEFINE (scm_object_address
, "object-address", 1, 0, 0,
844 "Return an integer that for the lifetime of @var{obj} is uniquely\n"
845 "returned by this function for @var{obj}")
846 #define FUNC_NAME s_scm_object_address
848 return scm_ulong2num ((unsigned long) SCM_UNPACK (obj
));
853 SCM_DEFINE (scm_gc
, "gc", 0, 0, 0,
855 "Scans all of SCM objects and reclaims for further use those that are\n"
856 "no longer accessible.")
857 #define FUNC_NAME s_scm_gc
862 return SCM_UNSPECIFIED
;
868 /* {C Interface For When GC is Triggered}
872 adjust_min_yield (scm_freelist_t
*freelist
)
874 /* min yield is adjusted upwards so that next predicted total yield
875 * (allocated cells actually freed by GC) becomes
876 * `min_yield_fraction' of total heap size. Note, however, that
877 * the absolute value of min_yield will correspond to `collected'
878 * on one master (the one which currently is triggering GC).
880 * The reason why we look at total yield instead of cells collected
881 * on one list is that we want to take other freelists into account.
882 * On this freelist, we know that (local) yield = collected cells,
883 * but that's probably not the case on the other lists.
885 * (We might consider computing a better prediction, for example
886 * by computing an average over multiple GC:s.)
888 if (freelist
->min_yield_fraction
)
890 /* Pick largest of last two yields. */
891 int delta
= ((SCM_HEAP_SIZE
* freelist
->min_yield_fraction
/ 100)
892 - (long) SCM_MAX (scm_gc_yield_1
, scm_gc_yield
));
894 fprintf (stderr
, " after GC = %d, delta = %d\n",
899 freelist
->min_yield
+= delta
;
904 /* When we get POSIX threads support, the master will be global and
905 * common while the freelist will be individual for each thread.
909 scm_gc_for_newcell (scm_freelist_t
*master
, SCM
*freelist
)
915 if (SCM_NULLP (master
->clusters
))
917 if (master
->grow_heap_p
|| scm_block_gc
)
919 /* In order to reduce gc frequency, try to allocate a new heap
920 * segment first, even if gc might find some free cells. If we
921 * can't obtain a new heap segment, we will try gc later.
923 master
->grow_heap_p
= 0;
924 alloc_some_heap (master
, return_on_error
);
926 if (SCM_NULLP (master
->clusters
))
928 /* The heap was not grown, either because it wasn't scheduled to
929 * grow, or because there was not enough memory available. In
930 * both cases we have to try gc to get some free cells.
933 fprintf (stderr
, "allocated = %d, ",
935 + master_cells_allocated (&scm_master_freelist
)
936 + master_cells_allocated (&scm_master_freelist2
));
939 adjust_min_yield (master
);
940 if (SCM_NULLP (master
->clusters
))
942 /* gc could not free any cells. Now, we _must_ allocate a
943 * new heap segment, because there is no other possibility
944 * to provide a new cell for the caller.
946 alloc_some_heap (master
, abort_on_error
);
950 cell
= SCM_CAR (master
->clusters
);
951 master
->clusters
= SCM_CDR (master
->clusters
);
952 ++master
->clusters_allocated
;
954 while (SCM_NULLP (cell
));
956 #ifdef GUILE_DEBUG_FREELIST
957 scm_check_freelist (cell
);
961 *freelist
= SCM_FREE_CELL_CDR (cell
);
967 /* This is a support routine which can be used to reserve a cluster
968 * for some special use, such as debugging. It won't be useful until
969 * free cells are preserved between garbage collections.
973 scm_alloc_cluster (scm_freelist_t
*master
)
976 cell
= scm_gc_for_newcell (master
, &freelist
);
977 SCM_SETCDR (cell
, freelist
);
983 scm_c_hook_t scm_before_gc_c_hook
;
984 scm_c_hook_t scm_before_mark_c_hook
;
985 scm_c_hook_t scm_before_sweep_c_hook
;
986 scm_c_hook_t scm_after_sweep_c_hook
;
987 scm_c_hook_t scm_after_gc_c_hook
;
991 scm_igc (const char *what
)
996 scm_c_hook_run (&scm_before_gc_c_hook
, 0);
999 SCM_NULLP (scm_freelist
)
1001 : (SCM_NULLP (scm_freelist2
) ? "o" : "m"));
1004 /* During the critical section, only the current thread may run. */
1005 SCM_THREAD_CRITICAL_SECTION_START
;
1008 /* fprintf (stderr, "gc: %s\n", what); */
1010 if (!scm_stack_base
|| scm_block_gc
)
1016 gc_start_stats (what
);
1018 if (scm_mallocated
< 0)
1019 /* The byte count of allocated objects has underflowed. This is
1020 probably because you forgot to report the sizes of objects you
1021 have allocated, by calling scm_done_malloc or some such. When
1022 the GC freed them, it subtracted their size from
1023 scm_mallocated, which underflowed. */
1026 if (scm_gc_heap_lock
)
1027 /* We've invoked the collector while a GC is already in progress.
1028 That should never happen. */
1033 /* flush dead entries from the continuation stack */
1038 elts
= SCM_VELTS (scm_continuation_stack
);
1039 bound
= SCM_VECTOR_LENGTH (scm_continuation_stack
);
1040 x
= SCM_INUM (scm_continuation_stack_ptr
);
1043 elts
[x
] = SCM_BOOL_F
;
1048 scm_c_hook_run (&scm_before_mark_c_hook
, 0);
1050 clear_mark_space ();
1054 /* Mark objects on the C stack. */
1055 SCM_FLUSH_REGISTER_WINDOWS
;
1056 /* This assumes that all registers are saved into the jmp_buf */
1057 setjmp (scm_save_regs_gc_mark
);
1058 scm_mark_locations ((SCM_STACKITEM
*) scm_save_regs_gc_mark
,
1059 ( (scm_sizet
) (sizeof (SCM_STACKITEM
) - 1 +
1060 sizeof scm_save_regs_gc_mark
)
1061 / sizeof (SCM_STACKITEM
)));
1064 scm_sizet stack_len
= scm_stack_size (scm_stack_base
);
1065 #ifdef SCM_STACK_GROWS_UP
1066 scm_mark_locations (scm_stack_base
, stack_len
);
1068 scm_mark_locations (scm_stack_base
- stack_len
, stack_len
);
1072 #else /* USE_THREADS */
1074 /* Mark every thread's stack and registers */
1075 scm_threads_mark_stacks ();
1077 #endif /* USE_THREADS */
1079 j
= SCM_NUM_PROTECTS
;
1081 scm_gc_mark (scm_sys_protects
[j
]);
1083 /* FIXME: we should have a means to register C functions to be run
1084 * in different phases of GC
1086 scm_mark_subr_table ();
1089 scm_gc_mark (scm_root
->handle
);
1092 t_before_sweep
= scm_c_get_internal_run_time ();
1093 scm_gc_mark_time_taken
+= (t_before_sweep
- t_before_gc
);
1095 scm_c_hook_run (&scm_before_sweep_c_hook
, 0);
1099 scm_c_hook_run (&scm_after_sweep_c_hook
, 0);
1105 SCM_THREAD_CRITICAL_SECTION_END
;
1107 scm_c_hook_run (&scm_after_gc_c_hook
, 0);
1116 #define MARK scm_gc_mark
1117 #define FNAME "scm_gc_mark"
1119 #endif /*!MARK_DEPENDENCIES*/
1121 /* Mark an object precisely.
1125 #define FUNC_NAME FNAME
1129 scm_bits_t cell_type
;
1131 #ifndef MARK_DEPENDENCIES
1132 # define RECURSE scm_gc_mark
1134 /* go through the usual marking, but not for self-cycles. */
1135 # define RECURSE(x) do { if ((x) != p) scm_gc_mark (x); } while (0)
1139 #ifdef MARK_DEPENDENCIES
1140 goto gc_mark_loop_first_time
;
1149 #ifdef MARK_DEPENDENCIES
1150 if (SCM_EQ_P (ptr
, p
))
1156 gc_mark_loop_first_time
:
1159 #if (SCM_DEBUG_CELL_ACCESSES == 1) || (defined (GUILE_DEBUG_FREELIST))
1160 /* We are in debug mode. Check the ptr exhaustively. */
1161 if (!scm_cellp (ptr
))
1162 SCM_MISC_ERROR ("rogue pointer in heap", SCM_EOL
);
1164 /* In non-debug mode, do at least some cheap testing. */
1165 if (!SCM_CELLP (ptr
))
1166 SCM_MISC_ERROR ("rogue pointer in heap", SCM_EOL
);
1169 #ifndef MARK_DEPENDENCIES
1171 if (SCM_GCMARKP (ptr
))
1174 SCM_SETGCMARK (ptr
);
1178 cell_type
= SCM_GC_CELL_TYPE (ptr
);
1179 switch (SCM_ITAG7 (cell_type
))
1181 case scm_tcs_cons_nimcar
:
1182 if (SCM_IMP (SCM_CDR (ptr
)))
1184 ptr
= SCM_CAR (ptr
);
1187 RECURSE (SCM_CAR (ptr
));
1188 ptr
= SCM_CDR (ptr
);
1190 case scm_tcs_cons_imcar
:
1191 ptr
= SCM_CDR (ptr
);
1194 RECURSE (SCM_SETTER (ptr
));
1195 ptr
= SCM_PROCEDURE (ptr
);
1197 case scm_tcs_cons_gloc
:
1199 /* Dirk:FIXME:: The following code is super ugly: ptr may be a struct
1200 * or a gloc. If it is a gloc, the cell word #0 of ptr is a pointer
1201 * to a heap cell. If it is a struct, the cell word #0 of ptr is a
1202 * pointer to a struct vtable data region. The fact that these are
1203 * accessed in the same way restricts the possibilites to change the
1204 * data layout of structs or heap cells.
1206 scm_bits_t word0
= SCM_CELL_WORD_0 (ptr
) - scm_tc3_cons_gloc
;
1207 scm_bits_t
* vtable_data
= (scm_bits_t
*) word0
; /* access as struct */
1208 if (vtable_data
[scm_vtable_index_vcell
] != 0)
1211 SCM gloc_car
= SCM_PACK (word0
);
1213 ptr
= SCM_CDR (ptr
);
1218 /* ptr is a struct */
1219 SCM layout
= SCM_PACK (vtable_data
[scm_vtable_index_layout
]);
1220 int len
= SCM_SYMBOL_LENGTH (layout
);
1221 char * fields_desc
= SCM_SYMBOL_CHARS (layout
);
1222 scm_bits_t
* struct_data
= (scm_bits_t
*) SCM_STRUCT_DATA (ptr
);
1224 if (vtable_data
[scm_struct_i_flags
] & SCM_STRUCTF_ENTITY
)
1226 RECURSE (SCM_PACK (struct_data
[scm_struct_i_procedure
]));
1227 RECURSE (SCM_PACK (struct_data
[scm_struct_i_setter
]));
1233 for (x
= 0; x
< len
- 2; x
+= 2, ++struct_data
)
1234 if (fields_desc
[x
] == 'p')
1235 RECURSE (SCM_PACK (*struct_data
));
1236 if (fields_desc
[x
] == 'p')
1238 if (SCM_LAYOUT_TAILP (fields_desc
[x
+ 1]))
1239 for (x
= *struct_data
++; x
; --x
, ++struct_data
)
1240 RECURSE (SCM_PACK (*struct_data
));
1242 RECURSE (SCM_PACK (*struct_data
));
1246 ptr
= SCM_PACK (vtable_data
[scm_vtable_index_vtable
]);
1251 case scm_tcs_closures
:
1252 if (SCM_IMP (SCM_ENV (ptr
)))
1254 ptr
= SCM_CLOSCAR (ptr
);
1257 RECURSE (SCM_CLOSCAR (ptr
));
1258 ptr
= SCM_ENV (ptr
);
1260 case scm_tc7_vector
:
1261 i
= SCM_VECTOR_LENGTH (ptr
);
1265 if (SCM_NIMP (SCM_VELTS (ptr
)[i
]))
1266 RECURSE (SCM_VELTS (ptr
)[i
]);
1267 ptr
= SCM_VELTS (ptr
)[0];
1272 unsigned long int i
= SCM_CCLO_LENGTH (ptr
);
1273 unsigned long int j
;
1274 for (j
= 1; j
!= i
; ++j
)
1276 SCM obj
= SCM_CCLO_REF (ptr
, j
);
1280 ptr
= SCM_CCLO_REF (ptr
, 0);
1286 case scm_tc7_byvect
:
1293 #ifdef HAVE_LONG_LONGS
1294 case scm_tc7_llvect
:
1297 case scm_tc7_string
:
1300 case scm_tc7_substring
:
1301 ptr
= SCM_CDR (ptr
);
1305 SCM_WVECT_GC_CHAIN (ptr
) = scm_weak_vectors
;
1306 scm_weak_vectors
= ptr
;
1307 if (SCM_IS_WHVEC_ANY (ptr
))
1314 len
= SCM_VECTOR_LENGTH (ptr
);
1315 weak_keys
= SCM_IS_WHVEC (ptr
) || SCM_IS_WHVEC_B (ptr
);
1316 weak_values
= SCM_IS_WHVEC_V (ptr
) || SCM_IS_WHVEC_B (ptr
);
1318 for (x
= 0; x
< len
; ++x
)
1321 alist
= SCM_VELTS (ptr
)[x
];
1323 /* mark everything on the alist except the keys or
1324 * values, according to weak_values and weak_keys. */
1325 while ( SCM_CONSP (alist
)
1326 && !SCM_GCMARKP (alist
)
1327 && SCM_CONSP (SCM_CAR (alist
)))
1332 kvpair
= SCM_CAR (alist
);
1333 next_alist
= SCM_CDR (alist
);
1336 * SCM_SETGCMARK (alist);
1337 * SCM_SETGCMARK (kvpair);
1339 * It may be that either the key or value is protected by
1340 * an escaped reference to part of the spine of this alist.
1341 * If we mark the spine here, and only mark one or neither of the
1342 * key and value, they may never be properly marked.
1343 * This leads to a horrible situation in which an alist containing
1344 * freelist cells is exported.
1346 * So only mark the spines of these arrays last of all marking.
1347 * If somebody confuses us by constructing a weak vector
1348 * with a circular alist then we are hosed, but at least we
1349 * won't prematurely drop table entries.
1352 RECURSE (SCM_CAR (kvpair
));
1354 RECURSE (SCM_CDR (kvpair
));
1357 if (SCM_NIMP (alist
))
1363 case scm_tc7_symbol
:
1364 ptr
= SCM_PROP_SLOTS (ptr
);
1369 i
= SCM_PTOBNUM (ptr
);
1370 if (!(i
< scm_numptob
))
1372 if (SCM_PTAB_ENTRY(ptr
))
1373 RECURSE (SCM_FILENAME (ptr
));
1374 if (scm_ptobs
[i
].mark
)
1376 ptr
= (scm_ptobs
[i
].mark
) (ptr
);
1383 switch (SCM_TYP16 (ptr
))
1384 { /* should be faster than going through scm_smobs */
1385 case scm_tc_free_cell
:
1386 /* printf("found free_cell %X ", ptr); fflush(stdout); */
1389 case scm_tc16_complex
:
1392 i
= SCM_SMOBNUM (ptr
);
1393 if (!(i
< scm_numsmob
))
1395 if (scm_smobs
[i
].mark
)
1397 ptr
= (scm_smobs
[i
].mark
) (ptr
);
1406 SCM_MISC_ERROR ("unknown type", SCM_EOL
);
1412 #ifndef MARK_DEPENDENCIES
1417 /* And here we define `scm_gc_mark_dependencies', by including this
1418 * same file in itself.
1420 #define MARK scm_gc_mark_dependencies
1421 #define FNAME "scm_gc_mark_dependencies"
1422 #define MARK_DEPENDENCIES
1424 #undef MARK_DEPENDENCIES
1429 /* Mark a Region Conservatively
1433 scm_mark_locations (SCM_STACKITEM x
[], scm_sizet n
)
1437 for (m
= 0; m
< n
; ++m
)
1439 SCM obj
= * (SCM
*) &x
[m
];
1440 if (SCM_CELLP (obj
))
1442 SCM_CELLPTR ptr
= SCM2PTR (obj
);
1444 int j
= scm_n_heap_segs
- 1;
1445 if (SCM_PTR_LE (scm_heap_table
[i
].bounds
[0], ptr
)
1446 && SCM_PTR_GT (scm_heap_table
[j
].bounds
[1], ptr
))
1453 || SCM_PTR_GT (scm_heap_table
[i
].bounds
[1], ptr
))
1455 else if (SCM_PTR_LE (scm_heap_table
[j
].bounds
[0], ptr
))
1463 if (SCM_PTR_GT (scm_heap_table
[k
].bounds
[1], ptr
))
1467 if (SCM_PTR_LE (scm_heap_table
[i
].bounds
[0], ptr
))
1472 else if (SCM_PTR_LE (scm_heap_table
[k
].bounds
[0], ptr
))
1476 if (SCM_PTR_GT (scm_heap_table
[j
].bounds
[1], ptr
))
1483 if (SCM_GC_IN_CARD_HEADERP (ptr
))
1486 if (scm_heap_table
[seg_id
].span
== 1
1487 || DOUBLECELL_ALIGNED_P (obj
))
1498 /* The function scm_cellp determines whether an SCM value can be regarded as a
1499 * pointer to a cell on the heap. Binary search is used in order to determine
1500 * the heap segment that contains the cell.
1503 scm_cellp (SCM value
)
1505 if (SCM_CELLP (value
)) {
1506 scm_cell
* ptr
= SCM2PTR (value
);
1508 unsigned int j
= scm_n_heap_segs
- 1;
1510 if (SCM_GC_IN_CARD_HEADERP (ptr
))
1514 int k
= (i
+ j
) / 2;
1515 if (SCM_PTR_GT (scm_heap_table
[k
].bounds
[1], ptr
)) {
1517 } else if (SCM_PTR_LE (scm_heap_table
[k
].bounds
[0], ptr
)) {
1522 if (SCM_PTR_LE (scm_heap_table
[i
].bounds
[0], ptr
)
1523 && SCM_PTR_GT (scm_heap_table
[i
].bounds
[1], ptr
)
1524 && (scm_heap_table
[i
].span
== 1 || DOUBLECELL_ALIGNED_P (value
))
1525 && !SCM_GC_IN_CARD_HEADERP (ptr
)
1536 gc_sweep_freelist_start (scm_freelist_t
*freelist
)
1538 freelist
->cells
= SCM_EOL
;
1539 freelist
->left_to_collect
= freelist
->cluster_size
;
1540 freelist
->clusters_allocated
= 0;
1541 freelist
->clusters
= SCM_EOL
;
1542 freelist
->clustertail
= &freelist
->clusters
;
1543 freelist
->collected_1
= freelist
->collected
;
1544 freelist
->collected
= 0;
1548 gc_sweep_freelist_finish (scm_freelist_t
*freelist
)
1551 *freelist
->clustertail
= freelist
->cells
;
1552 if (!SCM_NULLP (freelist
->cells
))
1554 SCM c
= freelist
->cells
;
1555 SCM_SET_CELL_WORD_0 (c
, SCM_FREE_CELL_CDR (c
));
1556 SCM_SET_CELL_WORD_1 (c
, SCM_EOL
);
1557 freelist
->collected
+=
1558 freelist
->span
* (freelist
->cluster_size
- freelist
->left_to_collect
);
1560 scm_gc_cells_collected
+= freelist
->collected
;
1562 /* Although freelist->min_yield is used to test freelist->collected
1563 * (which is the local GC yield for freelist), it is adjusted so
1564 * that *total* yield is freelist->min_yield_fraction of total heap
1565 * size. This means that a too low yield is compensated by more
1566 * heap on the list which is currently doing most work, which is
1567 * just what we want.
1569 collected
= SCM_MAX (freelist
->collected_1
, freelist
->collected
);
1570 freelist
->grow_heap_p
= (collected
< freelist
->min_yield
);
1573 #define NEXT_DATA_CELL(ptr, span) \
1575 scm_cell *nxt__ = CELL_UP ((char *) (ptr) + 1, (span)); \
1576 (ptr) = (SCM_GC_IN_CARD_HEADERP (nxt__) ? \
1577 CELL_UP (SCM_GC_CELL_CARD (nxt__) + SCM_GC_CARD_N_HEADER_CELLS, span) \
1583 #define FUNC_NAME "scm_gc_sweep"
1585 register SCM_CELLPTR ptr
;
1586 register SCM nfreelist
;
1587 register scm_freelist_t
*freelist
;
1595 gc_sweep_freelist_start (&scm_master_freelist
);
1596 gc_sweep_freelist_start (&scm_master_freelist2
);
1598 for (i
= 0; i
< scm_n_heap_segs
; i
++)
1600 register unsigned int left_to_collect
;
1601 register scm_sizet j
;
1603 /* Unmarked cells go onto the front of the freelist this heap
1604 segment points to. Rather than updating the real freelist
1605 pointer as we go along, we accumulate the new head in
1606 nfreelist. Then, if it turns out that the entire segment is
1607 free, we free (i.e., malloc's free) the whole segment, and
1608 simply don't assign nfreelist back into the real freelist. */
1609 freelist
= scm_heap_table
[i
].freelist
;
1610 nfreelist
= freelist
->cells
;
1611 left_to_collect
= freelist
->left_to_collect
;
1612 span
= scm_heap_table
[i
].span
;
1614 ptr
= CELL_UP (scm_heap_table
[i
].bounds
[0], span
);
1615 seg_size
= CELL_DN (scm_heap_table
[i
].bounds
[1], span
) - ptr
;
1617 /* use only data cells in seg_size */
1618 seg_size
= (seg_size
/ SCM_GC_CARD_N_CELLS
) * (SCM_GC_CARD_N_DATA_CELLS
/ span
) * span
;
1620 scm_gc_cells_swept
+= seg_size
;
1622 for (j
= seg_size
+ span
; j
-= span
; ptr
+= span
)
1626 if (SCM_GC_IN_CARD_HEADERP (ptr
))
1632 NEXT_DATA_CELL (nxt
, span
);
1639 scmptr
= PTR2SCM (ptr
);
1641 if (SCM_GCMARKP (scmptr
))
1644 switch SCM_TYP7 (scmptr
)
1646 case scm_tcs_cons_gloc
:
1648 /* Dirk:FIXME:: Again, super ugly code: scmptr may be a
1649 * struct or a gloc. See the corresponding comment in
1652 scm_bits_t word0
= (SCM_CELL_WORD_0 (scmptr
)
1653 - scm_tc3_cons_gloc
);
1654 /* access as struct */
1655 scm_bits_t
* vtable_data
= (scm_bits_t
*) word0
;
1656 if (vtable_data
[scm_vtable_index_vcell
] == 0)
1658 /* Structs need to be freed in a special order.
1659 * This is handled by GC C hooks in struct.c.
1661 SCM_SET_STRUCT_GC_CHAIN (scmptr
, scm_structs_to_free
);
1662 scm_structs_to_free
= scmptr
;
1665 /* fall through so that scmptr gets collected */
1668 case scm_tcs_cons_imcar
:
1669 case scm_tcs_cons_nimcar
:
1670 case scm_tcs_closures
:
1674 m
+= (2 + SCM_VECTOR_LENGTH (scmptr
)) * sizeof (SCM
);
1675 scm_must_free (SCM_VECTOR_BASE (scmptr
) - 2);
1677 case scm_tc7_vector
:
1679 unsigned long int length
= SCM_VECTOR_LENGTH (scmptr
);
1682 m
+= length
* sizeof (scm_bits_t
);
1683 scm_must_free (SCM_VECTOR_BASE (scmptr
));
1689 m
+= (SCM_CCLO_LENGTH (scmptr
) * sizeof (SCM
));
1690 scm_must_free (SCM_CCLO_BASE (scmptr
));
1696 unsigned long int length
= SCM_BITVECTOR_LENGTH (scmptr
);
1699 m
+= sizeof (long) * ((length
+ SCM_LONG_BIT
- 1) / SCM_LONG_BIT
);
1700 scm_must_free (SCM_BITVECTOR_BASE (scmptr
));
1704 case scm_tc7_byvect
:
1708 #ifdef HAVE_LONG_LONGS
1709 case scm_tc7_llvect
:
1714 m
+= SCM_UVECTOR_LENGTH (scmptr
) * scm_uniform_element_size (scmptr
);
1715 scm_must_free (SCM_UVECTOR_BASE (scmptr
));
1718 case scm_tc7_substring
:
1720 case scm_tc7_string
:
1721 m
+= SCM_STRING_LENGTH (scmptr
) + 1;
1722 scm_must_free (SCM_STRING_CHARS (scmptr
));
1724 case scm_tc7_symbol
:
1725 m
+= SCM_SYMBOL_LENGTH (scmptr
) + 1;
1726 scm_must_free (SCM_SYMBOL_CHARS (scmptr
));
1729 /* the various "subrs" (primitives) are never freed */
1732 if SCM_OPENP (scmptr
)
1734 int k
= SCM_PTOBNUM (scmptr
);
1735 if (!(k
< scm_numptob
))
1737 /* Keep "revealed" ports alive. */
1738 if (scm_revealed_count (scmptr
) > 0)
1740 /* Yes, I really do mean scm_ptobs[k].free */
1741 /* rather than ftobs[k].close. .close */
1742 /* is for explicit CLOSE-PORT by user */
1743 m
+= (scm_ptobs
[k
].free
) (scmptr
);
1744 SCM_SETSTREAM (scmptr
, 0);
1745 scm_remove_from_port_table (scmptr
);
1746 scm_gc_ports_collected
++;
1747 SCM_CLR_PORT_OPEN_FLAG (scmptr
);
1751 switch SCM_TYP16 (scmptr
)
1753 case scm_tc_free_cell
:
1758 m
+= (SCM_NUMDIGS (scmptr
) * SCM_BITSPERDIG
/ SCM_CHAR_BIT
);
1759 scm_must_free (SCM_BDIGITS (scmptr
));
1761 #endif /* def SCM_BIGDIG */
1762 case scm_tc16_complex
:
1763 m
+= sizeof (scm_complex_t
);
1764 scm_must_free (SCM_COMPLEX_MEM (scmptr
));
1769 k
= SCM_SMOBNUM (scmptr
);
1770 if (!(k
< scm_numsmob
))
1772 m
+= (scm_smobs
[k
].free
) (scmptr
);
1779 SCM_MISC_ERROR ("unknown type", SCM_EOL
);
1782 if (!--left_to_collect
)
1784 SCM_SET_CELL_WORD_0 (scmptr
, nfreelist
);
1785 *freelist
->clustertail
= scmptr
;
1786 freelist
->clustertail
= SCM_CDRLOC (scmptr
);
1788 nfreelist
= SCM_EOL
;
1789 freelist
->collected
+= span
* freelist
->cluster_size
;
1790 left_to_collect
= freelist
->cluster_size
;
1794 /* Stick the new cell on the front of nfreelist. It's
1795 critical that we mark this cell as freed; otherwise, the
1796 conservative collector might trace it as some other type
1798 SCM_SET_CELL_TYPE (scmptr
, scm_tc_free_cell
);
1799 SCM_SET_FREE_CELL_CDR (scmptr
, nfreelist
);
1804 #ifdef GC_FREE_SEGMENTS
1809 freelist
->heap_size
-= seg_size
;
1810 free ((char *) scm_heap_table
[i
].bounds
[0]);
1811 scm_heap_table
[i
].bounds
[0] = 0;
1812 for (j
= i
+ 1; j
< scm_n_heap_segs
; j
++)
1813 scm_heap_table
[j
- 1] = scm_heap_table
[j
];
1814 scm_n_heap_segs
-= 1;
1815 i
--; /* We need to scan the segment just moved. */
1818 #endif /* ifdef GC_FREE_SEGMENTS */
1820 /* Update the real freelist pointer to point to the head of
1821 the list of free cells we've built for this segment. */
1822 freelist
->cells
= nfreelist
;
1823 freelist
->left_to_collect
= left_to_collect
;
1826 #ifdef GUILE_DEBUG_FREELIST
1827 scm_map_free_list ();
1831 gc_sweep_freelist_finish (&scm_master_freelist
);
1832 gc_sweep_freelist_finish (&scm_master_freelist2
);
1834 /* When we move to POSIX threads private freelists should probably
1835 be GC-protected instead. */
1836 scm_freelist
= SCM_EOL
;
1837 scm_freelist2
= SCM_EOL
;
1839 scm_cells_allocated
= (SCM_HEAP_SIZE
- scm_gc_cells_collected
);
1840 scm_gc_yield
-= scm_cells_allocated
;
1841 scm_mallocated
-= m
;
1842 scm_gc_malloc_collected
= m
;
1848 /* {Front end to malloc}
1850 * scm_must_malloc, scm_must_realloc, scm_must_free, scm_done_malloc,
1853 * These functions provide services comparable to malloc, realloc, and
1854 * free. They should be used when allocating memory that will be under
1855 * control of the garbage collector, i.e., if the memory may be freed
1856 * during garbage collection.
1860 * Return newly malloced storage or throw an error.
1862 * The parameter WHAT is a string for error reporting.
1863 * If the threshold scm_mtrigger will be passed by this
1864 * allocation, or if the first call to malloc fails,
1865 * garbage collect -- on the presumption that some objects
1866 * using malloced storage may be collected.
1868 * The limit scm_mtrigger may be raised by this allocation.
1871 scm_must_malloc (scm_sizet size
, const char *what
)
1874 unsigned long nm
= scm_mallocated
+ size
;
1876 if (nm
<= scm_mtrigger
)
1878 SCM_SYSCALL (ptr
= malloc (size
));
1881 scm_mallocated
= nm
;
1882 #ifdef GUILE_DEBUG_MALLOC
1883 scm_malloc_register (ptr
, what
);
1891 nm
= scm_mallocated
+ size
;
1892 SCM_SYSCALL (ptr
= malloc (size
));
1895 scm_mallocated
= nm
;
1896 if (nm
> scm_mtrigger
- SCM_MTRIGGER_HYSTERESIS
) {
1897 if (nm
> scm_mtrigger
)
1898 scm_mtrigger
= nm
+ nm
/ 2;
1900 scm_mtrigger
+= scm_mtrigger
/ 2;
1902 #ifdef GUILE_DEBUG_MALLOC
1903 scm_malloc_register (ptr
, what
);
1909 scm_memory_error (what
);
1914 * is similar to scm_must_malloc.
1917 scm_must_realloc (void *where
,
1923 scm_sizet nm
= scm_mallocated
+ size
- old_size
;
1925 if (nm
<= scm_mtrigger
)
1927 SCM_SYSCALL (ptr
= realloc (where
, size
));
1930 scm_mallocated
= nm
;
1931 #ifdef GUILE_DEBUG_MALLOC
1932 scm_malloc_reregister (where
, ptr
, what
);
1940 nm
= scm_mallocated
+ size
- old_size
;
1941 SCM_SYSCALL (ptr
= realloc (where
, size
));
1944 scm_mallocated
= nm
;
1945 if (nm
> scm_mtrigger
- SCM_MTRIGGER_HYSTERESIS
) {
1946 if (nm
> scm_mtrigger
)
1947 scm_mtrigger
= nm
+ nm
/ 2;
1949 scm_mtrigger
+= scm_mtrigger
/ 2;
1951 #ifdef GUILE_DEBUG_MALLOC
1952 scm_malloc_reregister (where
, ptr
, what
);
1957 scm_memory_error (what
);
1962 scm_must_free (void *obj
)
1963 #define FUNC_NAME "scm_must_free"
1965 #ifdef GUILE_DEBUG_MALLOC
1966 scm_malloc_unregister (obj
);
1971 SCM_MISC_ERROR ("freeing NULL pointer", SCM_EOL
);
1976 /* Announce that there has been some malloc done that will be freed
1977 * during gc. A typical use is for a smob that uses some malloced
1978 * memory but can not get it from scm_must_malloc (for whatever
1979 * reason). When a new object of this smob is created you call
1980 * scm_done_malloc with the size of the object. When your smob free
1981 * function is called, be sure to include this size in the return
1984 * If you can't actually free the memory in the smob free function,
1985 * for whatever reason (like reference counting), you still can (and
1986 * should) report the amount of memory freed when you actually free it.
1987 * Do it by calling scm_done_malloc with the _negated_ size. Clever,
1988 * eh? Or even better, call scm_done_free. */
1991 scm_done_malloc (long size
)
1993 scm_mallocated
+= size
;
1995 if (scm_mallocated
> scm_mtrigger
)
1997 scm_igc ("foreign mallocs");
1998 if (scm_mallocated
> scm_mtrigger
- SCM_MTRIGGER_HYSTERESIS
)
2000 if (scm_mallocated
> scm_mtrigger
)
2001 scm_mtrigger
= scm_mallocated
+ scm_mallocated
/ 2;
2003 scm_mtrigger
+= scm_mtrigger
/ 2;
2009 scm_done_free (long size
)
2011 scm_mallocated
-= size
;
2018 * Each heap segment is an array of objects of a particular size.
2019 * Every segment has an associated (possibly shared) freelist.
2020 * A table of segment records is kept that records the upper and
2021 * lower extents of the segment; this is used during the conservative
2022 * phase of gc to identify probably gc roots (because they point
2023 * into valid segments at reasonable offsets). */
2026 * is true if the first segment was smaller than INIT_HEAP_SEG.
2027 * If scm_expmem is set to one, subsequent segment allocations will
2028 * allocate segments of size SCM_EXPHEAP(scm_heap_size).
2032 scm_sizet scm_max_segment_size
;
2035 * is the lowest base address of any heap segment.
2037 SCM_CELLPTR scm_heap_org
;
2039 scm_heap_seg_data_t
* scm_heap_table
= 0;
2040 static unsigned int heap_segment_table_size
= 0;
2041 int scm_n_heap_segs
= 0;
2044 * initializes a new heap segment and returns the number of objects it contains.
2046 * The segment origin and segment size in bytes are input parameters.
2047 * The freelist is both input and output.
2049 * This function presumes that the scm_heap_table has already been expanded
2050 * to accomodate a new segment record and that the markbit space was reserved
2051 * for all the cards in this segment.
2054 #define INIT_CARD(card, span) \
2056 SCM_GC_SET_CARD_BVEC (card, get_bvec ()); \
2058 SCM_GC_SET_CARD_DOUBLECELL (card); \
2062 init_heap_seg (SCM_CELLPTR seg_org
, scm_sizet size
, scm_freelist_t
*freelist
)
2064 register SCM_CELLPTR ptr
;
2065 SCM_CELLPTR seg_end
;
2068 int span
= freelist
->span
;
2070 if (seg_org
== NULL
)
2073 /* Align the begin ptr up.
2075 ptr
= SCM_GC_CARD_UP (seg_org
);
2077 /* Compute the ceiling on valid object pointers w/in this segment.
2079 seg_end
= SCM_GC_CARD_DOWN ((char *)seg_org
+ size
);
2081 /* Find the right place and insert the segment record.
2084 for (new_seg_index
= 0;
2085 ( (new_seg_index
< scm_n_heap_segs
)
2086 && SCM_PTR_LE (scm_heap_table
[new_seg_index
].bounds
[0], seg_org
));
2092 for (i
= scm_n_heap_segs
; i
> new_seg_index
; --i
)
2093 scm_heap_table
[i
] = scm_heap_table
[i
- 1];
2098 scm_heap_table
[new_seg_index
].span
= span
;
2099 scm_heap_table
[new_seg_index
].freelist
= freelist
;
2100 scm_heap_table
[new_seg_index
].bounds
[0] = ptr
;
2101 scm_heap_table
[new_seg_index
].bounds
[1] = seg_end
;
2104 n_new_cells
= seg_end
- ptr
;
2106 freelist
->heap_size
+= n_new_cells
;
2108 /* Partition objects in this segment into clusters */
2111 SCM
*clusterp
= &clusters
;
2113 NEXT_DATA_CELL (ptr
, span
);
2114 while (ptr
< seg_end
)
2116 scm_cell
*nxt
= ptr
;
2117 scm_cell
*prv
= NULL
;
2118 scm_cell
*last_card
= NULL
;
2119 int n_data_cells
= (SCM_GC_CARD_N_DATA_CELLS
/ span
) * SCM_CARDS_PER_CLUSTER
- 1;
2120 NEXT_DATA_CELL(nxt
, span
);
2122 /* Allocate cluster spine
2124 *clusterp
= PTR2SCM (ptr
);
2125 SCM_SETCAR (*clusterp
, PTR2SCM (nxt
));
2126 clusterp
= SCM_CDRLOC (*clusterp
);
2129 while (n_data_cells
--)
2131 scm_cell
*card
= SCM_GC_CELL_CARD (ptr
);
2132 SCM scmptr
= PTR2SCM (ptr
);
2134 NEXT_DATA_CELL (nxt
, span
);
2137 if (card
!= last_card
)
2139 INIT_CARD (card
, span
);
2143 SCM_SET_CELL_TYPE (scmptr
, scm_tc_free_cell
);
2144 SCM_SET_FREE_CELL_CDR (scmptr
, PTR2SCM (nxt
));
2149 SCM_SET_FREE_CELL_CDR (PTR2SCM (prv
), SCM_EOL
);
2154 scm_cell
*ref
= seg_end
;
2155 NEXT_DATA_CELL (ref
, span
);
2157 /* [cmm] looks like the segment size doesn't divide cleanly by
2158 cluster size. bad cmm! */
2162 /* Patch up the last cluster pointer in the segment
2163 * to join it to the input freelist.
2165 *clusterp
= freelist
->clusters
;
2166 freelist
->clusters
= clusters
;
2170 fprintf (stderr
, "H");
2176 round_to_cluster_size (scm_freelist_t
*freelist
, scm_sizet len
)
2178 scm_sizet cluster_size_in_bytes
= CLUSTER_SIZE_IN_BYTES (freelist
);
2181 (len
+ cluster_size_in_bytes
- 1) / cluster_size_in_bytes
* cluster_size_in_bytes
2182 + ALIGNMENT_SLACK (freelist
);
2186 alloc_some_heap (scm_freelist_t
*freelist
, policy_on_error error_policy
)
2187 #define FUNC_NAME "alloc_some_heap"
2192 if (scm_gc_heap_lock
)
2194 /* Critical code sections (such as the garbage collector) aren't
2195 * supposed to add heap segments.
2197 fprintf (stderr
, "alloc_some_heap: Can not extend locked heap.\n");
2201 if (scm_n_heap_segs
== heap_segment_table_size
)
2203 /* We have to expand the heap segment table to have room for the new
2204 * segment. Do not yet increment scm_n_heap_segs -- that is done by
2205 * init_heap_seg only if the allocation of the segment itself succeeds.
2207 unsigned int new_table_size
= scm_n_heap_segs
+ 1;
2208 size_t size
= new_table_size
* sizeof (scm_heap_seg_data_t
);
2209 scm_heap_seg_data_t
* new_heap_table
;
2211 SCM_SYSCALL (new_heap_table
= ((scm_heap_seg_data_t
*)
2212 realloc ((char *)scm_heap_table
, size
)));
2213 if (!new_heap_table
)
2215 if (error_policy
== abort_on_error
)
2217 fprintf (stderr
, "alloc_some_heap: Could not grow heap segment table.\n");
2227 scm_heap_table
= new_heap_table
;
2228 heap_segment_table_size
= new_table_size
;
2232 /* Pick a size for the new heap segment.
2233 * The rule for picking the size of a segment is explained in
2237 /* Assure that the new segment is predicted to be large enough.
2239 * New yield should at least equal GC fraction of new heap size, i.e.
2241 * y + dh > f * (h + dh)
2244 * f : min yield fraction
2246 * dh : size of new heap segment
2248 * This gives dh > (f * h - y) / (1 - f)
2250 int f
= freelist
->min_yield_fraction
;
2251 long h
= SCM_HEAP_SIZE
;
2252 long min_cells
= (f
* h
- 100 * (long) scm_gc_yield
) / (99 - f
);
2253 len
= SCM_EXPHEAP (freelist
->heap_size
);
2255 fprintf (stderr
, "(%d < %d)", len
, min_cells
);
2257 if (len
< min_cells
)
2258 len
= min_cells
+ freelist
->cluster_size
;
2259 len
*= sizeof (scm_cell
);
2260 /* force new sampling */
2261 freelist
->collected
= LONG_MAX
;
2264 if (len
> scm_max_segment_size
)
2265 len
= scm_max_segment_size
;
2270 smallest
= CLUSTER_SIZE_IN_BYTES (freelist
);
2275 /* Allocate with decaying ambition. */
2276 while ((len
>= SCM_MIN_HEAP_SEG_SIZE
)
2277 && (len
>= smallest
))
2279 scm_sizet rounded_len
= round_to_cluster_size (freelist
, len
);
2280 SCM_SYSCALL (ptr
= (SCM_CELLPTR
) malloc (rounded_len
));
2283 init_heap_seg (ptr
, rounded_len
, freelist
);
2290 if (error_policy
== abort_on_error
)
2292 fprintf (stderr
, "alloc_some_heap: Could not grow heap.\n");
2299 SCM_DEFINE (scm_unhash_name
, "unhash-name", 1, 0, 0,
2301 "Flushes the glocs for @var{name}, or all glocs if @var{name}\n"
2303 #define FUNC_NAME s_scm_unhash_name
2307 SCM_VALIDATE_SYMBOL (1,name
);
2309 bound
= scm_n_heap_segs
;
2310 for (x
= 0; x
< bound
; ++x
)
2314 p
= scm_heap_table
[x
].bounds
[0];
2315 pbound
= scm_heap_table
[x
].bounds
[1];
2318 SCM cell
= PTR2SCM (p
);
2319 if (SCM_TYP3 (cell
) == scm_tc3_cons_gloc
)
2321 /* Dirk:FIXME:: Again, super ugly code: cell may be a gloc or a
2322 * struct cell. See the corresponding comment in scm_gc_mark.
2324 scm_bits_t word0
= SCM_CELL_WORD_0 (cell
) - scm_tc3_cons_gloc
;
2325 SCM gloc_car
= SCM_PACK (word0
); /* access as gloc */
2326 SCM vcell
= SCM_CELL_OBJECT_1 (gloc_car
);
2327 if ((SCM_EQ_P (name
, SCM_BOOL_T
) || SCM_EQ_P (SCM_CAR (gloc_car
), name
))
2328 && (SCM_UNPACK (vcell
) != 0) && (SCM_UNPACK (vcell
) != 1))
2330 SCM_SET_CELL_OBJECT_0 (cell
, name
);
2343 /* {GC Protection Helper Functions}
2348 * If within a function you need to protect one or more scheme objects from
2349 * garbage collection, pass them as parameters to one of the
2350 * scm_remember_upto_here* functions below. These functions don't do
2351 * anything, but since the compiler does not know that they are actually
2352 * no-ops, it will generate code that calls these functions with the given
2353 * parameters. Therefore, you can be sure that the compiler will keep those
2354 * scheme values alive (on the stack or in a register) up to the point where
2355 * scm_remember_upto_here* is called. In other words, place the call to
2356 * scm_remember_upt_here* _behind_ the last code in your function, that
2357 * depends on the scheme object to exist.
2359 * Example: We want to make sure, that the string object str does not get
2360 * garbage collected during the execution of 'some_function', because
2361 * otherwise the characters belonging to str would be freed and
2362 * 'some_function' might access freed memory. To make sure that the compiler
2363 * keeps str alive on the stack or in a register such that it is visible to
2364 * the conservative gc we add the call to scm_remember_upto_here_1 _after_ the
2365 * call to 'some_function'. Note that this would not be necessary if str was
2366 * used anyway after the call to 'some_function'.
2367 * char *chars = SCM_STRING_CHARS (str);
2368 * some_function (chars);
2369 * scm_remember_upto_here_1 (str); // str will be alive up to this point.
2373 scm_remember_upto_here_1 (SCM obj
)
2375 /* Empty. Protects a single object from garbage collection. */
2379 scm_remember_upto_here_2 (SCM obj1
, SCM obj2
)
2381 /* Empty. Protects two objects from garbage collection. */
2385 scm_remember_upto_here (SCM obj
, ...)
2387 /* Empty. Protects any number of objects from garbage collection. */
2391 #if (SCM_DEBUG_DEPRECATED == 0)
2394 scm_remember (SCM
*ptr
)
2399 #endif /* SCM_DEBUG_DEPRECATED == 0 */
2402 These crazy functions prevent garbage collection
2403 of arguments after the first argument by
2404 ensuring they remain live throughout the
2405 function because they are used in the last
2406 line of the code block.
2407 It'd be better to have a nice compiler hint to
2408 aid the conservative stack-scanning GC. --03/09/00 gjb */
2410 scm_return_first (SCM elt
, ...)
2416 scm_return_first_int (int i
, ...)
2423 scm_permanent_object (SCM obj
)
2426 scm_permobjs
= scm_cons (obj
, scm_permobjs
);
2432 /* Protect OBJ from the garbage collector. OBJ will not be freed, even if all
2433 other references are dropped, until the object is unprotected by calling
2434 scm_unprotect_object (OBJ). Calls to scm_protect/unprotect_object nest,
2435 i. e. it is possible to protect the same object several times, but it is
2436 necessary to unprotect the object the same number of times to actually get
2437 the object unprotected. It is an error to unprotect an object more often
2438 than it has been protected before. The function scm_protect_object returns
2442 /* Implementation note: For every object X, there is a counter which
2443 scm_protect_object(X) increments and scm_unprotect_object(X) decrements.
2447 scm_protect_object (SCM obj
)
2451 /* This critical section barrier will be replaced by a mutex. */
2454 handle
= scm_hashq_create_handle_x (scm_protects
, obj
, SCM_MAKINUM (0));
2455 SCM_SETCDR (handle
, SCM_MAKINUM (SCM_INUM (SCM_CDR (handle
)) + 1));
2463 /* Remove any protection for OBJ established by a prior call to
2464 scm_protect_object. This function returns OBJ.
2466 See scm_protect_object for more information. */
2468 scm_unprotect_object (SCM obj
)
2472 /* This critical section barrier will be replaced by a mutex. */
2475 handle
= scm_hashq_get_handle (scm_protects
, obj
);
2477 if (SCM_FALSEP (handle
))
2479 fprintf (stderr
, "scm_unprotect_object called on unprotected object\n");
2484 unsigned long int count
= SCM_INUM (SCM_CDR (handle
)) - 1;
2486 scm_hashq_remove_x (scm_protects
, obj
);
2488 SCM_SETCDR (handle
, SCM_MAKINUM (count
));
2498 /* called on process termination. */
2504 extern int on_exit (void (*procp
) (), int arg
);
2507 cleanup (int status
, void *arg
)
2509 #error Dont know how to setup a cleanup handler on your system.
2514 scm_flush_all_ports ();
2519 make_initial_segment (scm_sizet init_heap_size
, scm_freelist_t
*freelist
)
2521 scm_sizet rounded_size
= round_to_cluster_size (freelist
, init_heap_size
);
2523 if (!init_heap_seg ((SCM_CELLPTR
) malloc (rounded_size
),
2527 rounded_size
= round_to_cluster_size (freelist
, SCM_HEAP_SEG_SIZE
);
2528 if (!init_heap_seg ((SCM_CELLPTR
) malloc (rounded_size
),
2536 if (freelist
->min_yield_fraction
)
2537 freelist
->min_yield
= (freelist
->heap_size
* freelist
->min_yield_fraction
2539 freelist
->grow_heap_p
= (freelist
->heap_size
< freelist
->min_yield
);
2546 init_freelist (scm_freelist_t
*freelist
,
2551 freelist
->clusters
= SCM_EOL
;
2552 freelist
->cluster_size
= cluster_size
+ 1;
2553 freelist
->left_to_collect
= 0;
2554 freelist
->clusters_allocated
= 0;
2555 freelist
->min_yield
= 0;
2556 freelist
->min_yield_fraction
= min_yield
;
2557 freelist
->span
= span
;
2558 freelist
->collected
= 0;
2559 freelist
->collected_1
= 0;
2560 freelist
->heap_size
= 0;
2564 /* Get an integer from an environment variable. */
2566 scm_i_getenv_int (const char *var
, int def
)
2568 char *end
, *val
= getenv (var
);
2572 res
= strtol (val
, &end
, 10);
2582 scm_sizet gc_trigger_1
;
2583 scm_sizet gc_trigger_2
;
2584 scm_sizet init_heap_size_1
;
2585 scm_sizet init_heap_size_2
;
2588 j
= SCM_NUM_PROTECTS
;
2590 scm_sys_protects
[--j
] = SCM_BOOL_F
;
2593 scm_freelist
= SCM_EOL
;
2594 scm_freelist2
= SCM_EOL
;
2595 gc_trigger_1
= scm_i_getenv_int ("GUILE_MIN_YIELD_1", scm_default_min_yield_1
);
2596 init_freelist (&scm_master_freelist
, 1, SCM_CLUSTER_SIZE_1
, gc_trigger_1
);
2597 gc_trigger_2
= scm_i_getenv_int ("GUILE_MIN_YIELD_2", scm_default_min_yield_2
);
2598 init_freelist (&scm_master_freelist2
, 2, SCM_CLUSTER_SIZE_2
, gc_trigger_2
);
2599 scm_max_segment_size
= scm_i_getenv_int ("GUILE_MAX_SEGMENT_SIZE", scm_default_max_segment_size
);
2603 j
= SCM_HEAP_SEG_SIZE
;
2604 scm_mtrigger
= SCM_INIT_MALLOC_LIMIT
;
2605 scm_heap_table
= ((scm_heap_seg_data_t
*)
2606 scm_must_malloc (sizeof (scm_heap_seg_data_t
) * 2, "hplims"));
2607 heap_segment_table_size
= 2;
2609 mark_space_ptr
= &mark_space_head
;
2611 init_heap_size_1
= scm_i_getenv_int ("GUILE_INIT_SEGMENT_SIZE_1", scm_default_init_heap_size_1
);
2612 init_heap_size_2
= scm_i_getenv_int ("GUILE_INIT_SEGMENT_SIZE_2", scm_default_init_heap_size_2
);
2613 if (make_initial_segment (init_heap_size_1
, &scm_master_freelist
) ||
2614 make_initial_segment (init_heap_size_2
, &scm_master_freelist2
))
2617 /* scm_hplims[0] can change. do not remove scm_heap_org */
2618 scm_heap_org
= CELL_UP (scm_heap_table
[0].bounds
[0], 1);
2620 scm_c_hook_init (&scm_before_gc_c_hook
, 0, SCM_C_HOOK_NORMAL
);
2621 scm_c_hook_init (&scm_before_mark_c_hook
, 0, SCM_C_HOOK_NORMAL
);
2622 scm_c_hook_init (&scm_before_sweep_c_hook
, 0, SCM_C_HOOK_NORMAL
);
2623 scm_c_hook_init (&scm_after_sweep_c_hook
, 0, SCM_C_HOOK_NORMAL
);
2624 scm_c_hook_init (&scm_after_gc_c_hook
, 0, SCM_C_HOOK_NORMAL
);
2626 /* Initialise the list of ports. */
2627 scm_port_table
= (scm_port
**)
2628 malloc (sizeof (scm_port
*) * scm_port_table_room
);
2629 if (!scm_port_table
)
2636 on_exit (cleanup
, 0);
2640 scm_undefineds
= scm_cons (SCM_UNDEFINED
, SCM_EOL
);
2641 SCM_SETCDR (scm_undefineds
, scm_undefineds
);
2643 scm_listofnull
= scm_cons (SCM_EOL
, SCM_EOL
);
2644 scm_nullstr
= scm_allocate_string (0);
2645 scm_nullvect
= scm_c_make_vector (0, SCM_UNDEFINED
);
2647 #define DEFAULT_SYMHASH_SIZE 277
2648 scm_symhash
= scm_c_make_hash_table (DEFAULT_SYMHASH_SIZE
);
2649 scm_symhash_vars
= scm_c_make_hash_table (DEFAULT_SYMHASH_SIZE
);
2651 scm_stand_in_procs
= SCM_EOL
;
2652 scm_permobjs
= SCM_EOL
;
2653 scm_protects
= scm_c_make_hash_table (31);
2660 SCM scm_after_gc_hook
;
2662 #if (SCM_DEBUG_DEPRECATED == 0)
2663 static SCM scm_gc_vcell
; /* the vcell for gc-thunk. */
2664 #endif /* SCM_DEBUG_DEPRECATED == 0 */
2665 static SCM gc_async
;
2668 /* The function gc_async_thunk causes the execution of the after-gc-hook. It
2669 * is run after the gc, as soon as the asynchronous events are handled by the
2673 gc_async_thunk (void)
2675 scm_c_run_hook (scm_after_gc_hook
, SCM_EOL
);
2677 #if (SCM_DEBUG_DEPRECATED == 0)
2679 /* The following code will be removed in Guile 1.5. */
2680 if (SCM_NFALSEP (scm_gc_vcell
))
2682 SCM proc
= SCM_CDR (scm_gc_vcell
);
2684 if (SCM_NFALSEP (proc
) && !SCM_UNBNDP (proc
))
2685 scm_apply (proc
, SCM_EOL
, SCM_EOL
);
2688 #endif /* SCM_DEBUG_DEPRECATED == 0 */
2690 return SCM_UNSPECIFIED
;
2694 /* The function mark_gc_async is run by the scm_after_gc_c_hook at the end of
2695 * the garbage collection. The only purpose of this function is to mark the
2696 * gc_async (which will eventually lead to the execution of the
2700 mark_gc_async (void * hook_data
, void *func_data
, void *data
)
2702 scm_system_async_mark (gc_async
);
2712 #if (SCM_DEBUG_CELL_ACCESSES == 1)
2713 scm_tc16_allocated
= scm_make_smob_type ("allocated cell", 0);
2714 #endif /* SCM_DEBUG_CELL_ACCESSES == 1 */
2716 scm_after_gc_hook
= scm_create_hook ("after-gc-hook", 0);
2718 #if (SCM_DEBUG_DEPRECATED == 0)
2719 scm_gc_vcell
= scm_sysintern ("gc-thunk", SCM_BOOL_F
);
2720 #endif /* SCM_DEBUG_DEPRECATED == 0 */
2721 after_gc_thunk
= scm_make_subr_opt ("%gc-thunk", scm_tc7_subr_0
, gc_async_thunk
, 0);
2722 gc_async
= scm_system_async (after_gc_thunk
); /* protected via scm_asyncs */
2724 scm_c_hook_add (&scm_after_gc_c_hook
, mark_gc_async
, NULL
, 0);
2726 #ifndef SCM_MAGIC_SNARFER
2727 #include "libguile/gc.x"
2731 #endif /*MARK_DEPENDENCIES*/