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/deprecation.h"
75 #include "libguile/gc.h"
77 #ifdef GUILE_DEBUG_MALLOC
78 #include "libguile/debug-malloc.h"
91 #define var_start(x, y) va_start(x, y)
94 #define var_start(x, y) va_start(x)
99 unsigned int scm_gc_running_p
= 0;
103 #if (SCM_DEBUG_CELL_ACCESSES == 1)
105 scm_bits_t scm_tc16_allocated
;
107 /* Set this to != 0 if every cell that is accessed shall be checked:
109 unsigned int scm_debug_cell_accesses_p
= 1;
112 /* Assert that the given object is a valid reference to a valid cell. This
113 * test involves to determine whether the object is a cell pointer, whether
114 * this pointer actually points into a heap segment and whether the cell
115 * pointed to is not a free cell.
118 scm_assert_cell_valid (SCM cell
)
120 static unsigned int already_running
= 0;
122 if (scm_debug_cell_accesses_p
&& !already_running
)
124 already_running
= 1; /* set to avoid recursion */
126 if (!scm_cellp (cell
))
128 fprintf (stderr
, "scm_assert_cell_valid: Not a cell object: %lux\n",
129 (unsigned long) SCM_UNPACK (cell
));
132 else if (!scm_gc_running_p
)
134 /* Dirk::FIXME:: During garbage collection there occur references to
135 free cells. This is allright during conservative marking, but
136 should not happen otherwise (I think). The case of free cells
137 accessed during conservative marking is handled in function
138 scm_mark_locations. However, there still occur accesses to free
139 cells during gc. I don't understand why this happens. If it is
140 a bug and gets fixed, the following test should also work while
143 if (SCM_FREE_CELL_P (cell
))
145 fprintf (stderr
, "scm_assert_cell_valid: Accessing free cell: %lux\n",
146 (unsigned long) SCM_UNPACK (cell
));
150 already_running
= 0; /* re-enable */
155 SCM_DEFINE (scm_set_debug_cell_accesses_x
, "set-debug-cell-accesses!", 1, 0, 0,
157 "If @var{flag} is @code{#f}, cell access checking is disabled.\n"
158 "If @var{flag} is @code{#t}, cell access checking is enabled.\n"
159 "This procedure only exists when the compile-time flag\n"
160 "@code{SCM_DEBUG_CELL_ACCESSES} was set to 1.")
161 #define FUNC_NAME s_scm_set_debug_cell_accesses_x
163 if (SCM_FALSEP (flag
)) {
164 scm_debug_cell_accesses_p
= 0;
165 } else if (SCM_EQ_P (flag
, SCM_BOOL_T
)) {
166 scm_debug_cell_accesses_p
= 1;
168 SCM_WRONG_TYPE_ARG (1, flag
);
170 return SCM_UNSPECIFIED
;
174 #endif /* SCM_DEBUG_CELL_ACCESSES == 1 */
178 /* {heap tuning parameters}
180 * These are parameters for controlling memory allocation. The heap
181 * is the area out of which scm_cons, and object headers are allocated.
183 * Each heap cell is 8 bytes on a 32 bit machine and 16 bytes on a
184 * 64 bit machine. The units of the _SIZE parameters are bytes.
185 * Cons pairs and object headers occupy one heap cell.
187 * SCM_INIT_HEAP_SIZE is the initial size of heap. If this much heap is
188 * allocated initially the heap will grow by half its current size
189 * each subsequent time more heap is needed.
191 * If SCM_INIT_HEAP_SIZE heap cannot be allocated initially, SCM_HEAP_SEG_SIZE
192 * will be used, and the heap will grow by SCM_HEAP_SEG_SIZE when more
193 * heap is needed. SCM_HEAP_SEG_SIZE must fit into type size_t. This code
194 * is in scm_init_storage() and alloc_some_heap() in sys.c
196 * If SCM_INIT_HEAP_SIZE can be allocated initially, the heap will grow by
197 * SCM_EXPHEAP(scm_heap_size) when more heap is needed.
199 * SCM_MIN_HEAP_SEG_SIZE is minimum size of heap to accept when more heap
202 * INIT_MALLOC_LIMIT is the initial amount of malloc usage which will
205 * SCM_MTRIGGER_HYSTERESIS is the amount of malloc storage that must be
206 * reclaimed by a GC triggered by must_malloc. If less than this is
207 * reclaimed, the trigger threshold is raised. [I don't know what a
208 * good value is. I arbitrarily chose 1/10 of the INIT_MALLOC_LIMIT to
209 * work around a oscillation that caused almost constant GC.]
213 * Heap size 45000 and 40% min yield gives quick startup and no extra
214 * heap allocation. Having higher values on min yield may lead to
215 * large heaps, especially if code behaviour is varying its
216 * maximum consumption between different freelists.
219 #define SCM_DATA_CELLS2CARDS(n) (((n) + SCM_GC_CARD_N_DATA_CELLS - 1) / SCM_GC_CARD_N_DATA_CELLS)
220 #define SCM_CARDS_PER_CLUSTER SCM_DATA_CELLS2CARDS (2000L)
221 #define SCM_CLUSTER_SIZE_1 (SCM_CARDS_PER_CLUSTER * SCM_GC_CARD_N_DATA_CELLS)
222 size_t scm_default_init_heap_size_1
= (((SCM_DATA_CELLS2CARDS (45000L) + SCM_CARDS_PER_CLUSTER
- 1)
223 / SCM_CARDS_PER_CLUSTER
) * SCM_GC_CARD_SIZE
);
224 int scm_default_min_yield_1
= 40;
226 #define SCM_CLUSTER_SIZE_2 (SCM_CARDS_PER_CLUSTER * (SCM_GC_CARD_N_DATA_CELLS / 2))
227 size_t scm_default_init_heap_size_2
= (((SCM_DATA_CELLS2CARDS (2500L * 2) + SCM_CARDS_PER_CLUSTER
- 1)
228 / SCM_CARDS_PER_CLUSTER
) * SCM_GC_CARD_SIZE
);
229 /* The following value may seem large, but note that if we get to GC at
230 * all, this means that we have a numerically intensive application
232 int scm_default_min_yield_2
= 40;
234 size_t scm_default_max_segment_size
= 2097000L;/* a little less (adm) than 2 Mb */
236 #define SCM_MIN_HEAP_SEG_SIZE (8 * SCM_GC_CARD_SIZE)
238 # define SCM_HEAP_SEG_SIZE 32768L
241 # define SCM_HEAP_SEG_SIZE (7000L * sizeof (scm_cell))
243 # define SCM_HEAP_SEG_SIZE (16384L * sizeof (scm_cell))
246 /* Make heap grow with factor 1.5 */
247 #define SCM_EXPHEAP(scm_heap_size) (scm_heap_size / 2)
248 #define SCM_INIT_MALLOC_LIMIT 100000
249 #define SCM_MTRIGGER_HYSTERESIS (SCM_INIT_MALLOC_LIMIT/10)
251 /* CELL_UP and CELL_DN are used by scm_init_heap_seg to find (scm_cell * span)
252 aligned inner bounds for allocated storage */
255 /*in 386 protected mode we must only adjust the offset */
256 # define CELL_UP(p, span) MK_FP(FP_SEG(p), ~(8*(span)-1)&(FP_OFF(p)+8*(span)-1))
257 # define CELL_DN(p, span) MK_FP(FP_SEG(p), ~(8*(span)-1)&FP_OFF(p))
260 # define CELL_UP(p, span) (SCM_CELLPTR)(~(span) & ((long)(p)+(span)))
261 # define CELL_DN(p, span) (SCM_CELLPTR)(~(span) & (long)(p))
263 # define CELL_UP(p, span) (SCM_CELLPTR)(~(sizeof(scm_cell)*(span)-1L) & ((long)(p)+sizeof(scm_cell)*(span)-1L))
264 # define CELL_DN(p, span) (SCM_CELLPTR)(~(sizeof(scm_cell)*(span)-1L) & (long)(p))
268 #define DOUBLECELL_ALIGNED_P(x) (((2 * sizeof (scm_cell) - 1) & SCM_UNPACK (x)) == 0)
270 #define ALIGNMENT_SLACK(freelist) (SCM_GC_CARD_SIZE - 1)
271 #define CLUSTER_SIZE_IN_BYTES(freelist) \
272 (((freelist)->cluster_size / (SCM_GC_CARD_N_DATA_CELLS / (freelist)->span)) * SCM_GC_CARD_SIZE)
278 typedef struct scm_freelist_t
{
279 /* collected cells */
281 /* number of cells left to collect before cluster is full */
282 unsigned int left_to_collect
;
283 /* number of clusters which have been allocated */
284 unsigned int clusters_allocated
;
285 /* a list of freelists, each of size cluster_size,
286 * except the last one which may be shorter
290 /* this is the number of objects in each cluster, including the spine cell */
291 unsigned int cluster_size
;
292 /* indicates that we should grow heap instead of GC:ing
295 /* minimum yield on this list in order not to grow the heap
298 /* defines min_yield as percent of total heap size
300 int min_yield_fraction
;
301 /* number of cells per object on this list */
303 /* number of collected cells during last GC */
304 unsigned long collected
;
305 /* number of collected cells during penultimate GC */
306 unsigned long collected_1
;
307 /* total number of cells in heap segments
308 * belonging to this list.
310 unsigned long heap_size
;
313 SCM scm_freelist
= SCM_EOL
;
314 scm_freelist_t scm_master_freelist
= {
315 SCM_EOL
, 0, 0, SCM_EOL
, 0, SCM_CLUSTER_SIZE_1
, 0, 0, 0, 1, 0, 0
317 SCM scm_freelist2
= SCM_EOL
;
318 scm_freelist_t scm_master_freelist2
= {
319 SCM_EOL
, 0, 0, SCM_EOL
, 0, SCM_CLUSTER_SIZE_2
, 0, 0, 0, 2, 0, 0
323 * is the number of bytes of must_malloc allocation needed to trigger gc.
325 unsigned long scm_mtrigger
;
328 * If set, don't expand the heap. Set only during gc, during which no allocation
329 * is supposed to take place anyway.
331 int scm_gc_heap_lock
= 0;
334 * Don't pause for collection if this is set -- just
337 int scm_block_gc
= 1;
339 /* During collection, this accumulates objects holding
342 SCM scm_weak_vectors
;
344 /* During collection, this accumulates structures which are to be freed.
346 SCM scm_structs_to_free
;
348 /* GC Statistics Keeping
350 unsigned long scm_cells_allocated
= 0;
351 unsigned long scm_mallocated
= 0;
352 unsigned long scm_gc_cells_collected
;
353 unsigned long scm_gc_yield
;
354 static unsigned long scm_gc_yield_1
= 0; /* previous GC yield */
355 unsigned long scm_gc_malloc_collected
;
356 unsigned long scm_gc_ports_collected
;
357 unsigned long scm_gc_time_taken
= 0;
358 static unsigned long t_before_gc
;
359 static unsigned long t_before_sweep
;
360 unsigned long scm_gc_mark_time_taken
= 0;
361 unsigned long scm_gc_sweep_time_taken
= 0;
362 unsigned long scm_gc_times
= 0;
363 unsigned long scm_gc_cells_swept
= 0;
364 double scm_gc_cells_marked_acc
= 0.;
365 double scm_gc_cells_swept_acc
= 0.;
367 SCM_SYMBOL (sym_cells_allocated
, "cells-allocated");
368 SCM_SYMBOL (sym_heap_size
, "cell-heap-size");
369 SCM_SYMBOL (sym_mallocated
, "bytes-malloced");
370 SCM_SYMBOL (sym_mtrigger
, "gc-malloc-threshold");
371 SCM_SYMBOL (sym_heap_segments
, "cell-heap-segments");
372 SCM_SYMBOL (sym_gc_time_taken
, "gc-time-taken");
373 SCM_SYMBOL (sym_gc_mark_time_taken
, "gc-mark-time-taken");
374 SCM_SYMBOL (sym_gc_sweep_time_taken
, "gc-sweep-time-taken");
375 SCM_SYMBOL (sym_times
, "gc-times");
376 SCM_SYMBOL (sym_cells_marked
, "cells-marked");
377 SCM_SYMBOL (sym_cells_swept
, "cells-swept");
379 typedef struct scm_heap_seg_data_t
381 /* lower and upper bounds of the segment */
382 SCM_CELLPTR bounds
[2];
384 /* address of the head-of-freelist pointer for this segment's cells.
385 All segments usually point to the same one, scm_freelist. */
386 scm_freelist_t
*freelist
;
388 /* number of cells per object in this segment */
390 } scm_heap_seg_data_t
;
394 static size_t init_heap_seg (SCM_CELLPTR
, size_t, scm_freelist_t
*);
396 typedef enum { return_on_error
, abort_on_error
} policy_on_error
;
397 static void alloc_some_heap (scm_freelist_t
*, policy_on_error
);
400 #define SCM_HEAP_SIZE \
401 (scm_master_freelist.heap_size + scm_master_freelist2.heap_size)
402 #define SCM_MAX(A, B) ((A) > (B) ? (A) : (B))
404 #define BVEC_GROW_SIZE 256
405 #define BVEC_GROW_SIZE_IN_LIMBS (SCM_GC_CARD_BVEC_SIZE_IN_LIMBS * BVEC_GROW_SIZE)
406 #define BVEC_GROW_SIZE_IN_BYTES (BVEC_GROW_SIZE_IN_LIMBS * sizeof (scm_c_bvec_limb_t))
408 /* mark space allocation */
410 typedef struct scm_mark_space_t
412 scm_c_bvec_limb_t
*bvec_space
;
413 struct scm_mark_space_t
*next
;
416 static scm_mark_space_t
*current_mark_space
;
417 static scm_mark_space_t
**mark_space_ptr
;
418 static ptrdiff_t current_mark_space_offset
;
419 static scm_mark_space_t
*mark_space_head
;
421 static scm_c_bvec_limb_t
*
423 #define FUNC_NAME "get_bvec"
425 scm_c_bvec_limb_t
*res
;
427 if (!current_mark_space
)
429 SCM_SYSCALL (current_mark_space
= (scm_mark_space_t
*) malloc (sizeof (scm_mark_space_t
)));
430 if (!current_mark_space
)
431 SCM_MISC_ERROR ("could not grow heap", SCM_EOL
);
433 current_mark_space
->bvec_space
= NULL
;
434 current_mark_space
->next
= NULL
;
436 *mark_space_ptr
= current_mark_space
;
437 mark_space_ptr
= &(current_mark_space
->next
);
442 if (!(current_mark_space
->bvec_space
))
444 SCM_SYSCALL (current_mark_space
->bvec_space
=
445 (scm_c_bvec_limb_t
*) calloc (BVEC_GROW_SIZE_IN_BYTES
, 1));
446 if (!(current_mark_space
->bvec_space
))
447 SCM_MISC_ERROR ("could not grow heap", SCM_EOL
);
449 current_mark_space_offset
= 0;
454 if (current_mark_space_offset
== BVEC_GROW_SIZE_IN_LIMBS
)
456 current_mark_space
= NULL
;
461 res
= current_mark_space
->bvec_space
+ current_mark_space_offset
;
462 current_mark_space_offset
+= SCM_GC_CARD_BVEC_SIZE_IN_LIMBS
;
472 scm_mark_space_t
*ms
;
474 for (ms
= mark_space_head
; ms
; ms
= ms
->next
)
475 memset (ms
->bvec_space
, 0, BVEC_GROW_SIZE_IN_BYTES
);
480 /* Debugging functions. */
482 #if defined (GUILE_DEBUG) || defined (GUILE_DEBUG_FREELIST)
484 /* Return the number of the heap segment containing CELL. */
490 for (i
= 0; i
< scm_n_heap_segs
; i
++)
491 if (SCM_PTR_LE (scm_heap_table
[i
].bounds
[0], SCM2PTR (cell
))
492 && SCM_PTR_GT (scm_heap_table
[i
].bounds
[1], SCM2PTR (cell
)))
494 fprintf (stderr
, "which_seg: can't find segment containing cell %lux\n",
495 (unsigned long) SCM_UNPACK (cell
));
501 map_free_list (scm_freelist_t
*master
, SCM freelist
)
503 long last_seg
= -1, count
= 0;
506 for (f
= freelist
; !SCM_NULLP (f
); f
= SCM_FREE_CELL_CDR (f
))
508 long this_seg
= which_seg (f
);
510 if (this_seg
!= last_seg
)
513 fprintf (stderr
, " %5ld %d-cells in segment %ld\n",
514 (long) count
, master
->span
, (long) last_seg
);
521 fprintf (stderr
, " %5ld %d-cells in segment %ld\n",
522 (long) count
, master
->span
, (long) last_seg
);
525 SCM_DEFINE (scm_map_free_list
, "map-free-list", 0, 0, 0,
527 "Print debugging information about the free-list.\n"
528 "@code{map-free-list} is only included in\n"
529 "@code{--enable-guile-debug} builds of Guile.")
530 #define FUNC_NAME s_scm_map_free_list
533 fprintf (stderr
, "%ld segments total (%d:%ld",
534 (long) scm_n_heap_segs
,
535 scm_heap_table
[0].span
,
536 (long) (scm_heap_table
[0].bounds
[1] - scm_heap_table
[0].bounds
[0]));
537 for (i
= 1; i
< scm_n_heap_segs
; i
++)
538 fprintf (stderr
, ", %d:%ld",
539 scm_heap_table
[i
].span
,
540 (long) (scm_heap_table
[i
].bounds
[1] - scm_heap_table
[i
].bounds
[0]));
541 fprintf (stderr
, ")\n");
542 map_free_list (&scm_master_freelist
, scm_freelist
);
543 map_free_list (&scm_master_freelist2
, scm_freelist2
);
546 return SCM_UNSPECIFIED
;
550 static long last_cluster
;
551 static long last_size
;
554 free_list_length (char *title
, long i
, SCM freelist
)
558 for (ls
= freelist
; !SCM_NULLP (ls
); ls
= SCM_FREE_CELL_CDR (ls
))
559 if (SCM_FREE_CELL_P (ls
))
563 fprintf (stderr
, "bad cell in %s at position %ld\n", title
, (long) n
);
570 if (last_cluster
== i
- 1)
571 fprintf (stderr
, "\t%ld\n", (long) last_size
);
573 fprintf (stderr
, "-%ld\t%ld\n", (long) (i
- 1), (long) last_size
);
576 fprintf (stderr
, "%s %ld", title
, (long) i
);
578 fprintf (stderr
, "%s\t%ld\n", title
, (long) n
);
586 free_list_lengths (char *title
, scm_freelist_t
*master
, SCM freelist
)
589 long i
= 0, len
, n
= 0;
590 fprintf (stderr
, "%s\n\n", title
);
591 n
+= free_list_length ("free list", -1, freelist
);
592 for (clusters
= master
->clusters
;
593 SCM_NNULLP (clusters
);
594 clusters
= SCM_CDR (clusters
))
596 len
= free_list_length ("cluster", i
++, SCM_CAR (clusters
));
599 if (last_cluster
== i
- 1)
600 fprintf (stderr
, "\t%ld\n", (long) last_size
);
602 fprintf (stderr
, "-%ld\t%ld\n", (long) (i
- 1), (long) last_size
);
603 fprintf (stderr
, "\ntotal %ld objects\n\n", (long) n
);
606 SCM_DEFINE (scm_free_list_length
, "free-list-length", 0, 0, 0,
608 "Print debugging information about the free-list.\n"
609 "@code{free-list-length} is only included in\n"
610 "@code{--enable-guile-debug} builds of Guile.")
611 #define FUNC_NAME s_scm_free_list_length
613 free_list_lengths ("1-cells", &scm_master_freelist
, scm_freelist
);
614 free_list_lengths ("2-cells", &scm_master_freelist2
, scm_freelist2
);
615 return SCM_UNSPECIFIED
;
621 #ifdef GUILE_DEBUG_FREELIST
623 /* Non-zero if freelist debugging is in effect. Set this via
624 `gc-set-debug-check-freelist!'. */
625 static int scm_debug_check_freelist
= 0;
627 /* Number of calls to SCM_NEWCELL since startup. */
628 static unsigned long scm_newcell_count
;
629 static unsigned long scm_newcell2_count
;
631 /* Search freelist for anything that isn't marked as a free cell.
632 Abort if we find something. */
634 scm_check_freelist (SCM freelist
)
639 for (f
= freelist
; !SCM_NULLP (f
); f
= SCM_FREE_CELL_CDR (f
), i
++)
640 if (!SCM_FREE_CELL_P (f
))
642 fprintf (stderr
, "Bad cell in freelist on newcell %lu: %lu'th elt\n",
643 (long) scm_newcell_count
, (long) i
);
648 SCM_DEFINE (scm_gc_set_debug_check_freelist_x
, "gc-set-debug-check-freelist!", 1, 0, 0,
650 "If @var{flag} is @code{#t}, check the freelist for consistency\n"
651 "on each cell allocation. This procedure only exists when the\n"
652 "@code{GUILE_DEBUG_FREELIST} compile-time flag was selected.")
653 #define FUNC_NAME s_scm_gc_set_debug_check_freelist_x
655 /* [cmm] I did a double-take when I read this code the first time.
657 SCM_VALIDATE_BOOL_COPY (1, flag
, scm_debug_check_freelist
);
658 return SCM_UNSPECIFIED
;
664 scm_debug_newcell (void)
669 if (scm_debug_check_freelist
)
671 scm_check_freelist (scm_freelist
);
675 /* The rest of this is supposed to be identical to the SCM_NEWCELL
677 if (SCM_NULLP (scm_freelist
))
679 new = scm_gc_for_newcell (&scm_master_freelist
, &scm_freelist
);
680 SCM_GC_SET_ALLOCATED (new);
685 scm_freelist
= SCM_FREE_CELL_CDR (scm_freelist
);
686 SCM_GC_SET_ALLOCATED (new);
693 scm_debug_newcell2 (void)
697 scm_newcell2_count
++;
698 if (scm_debug_check_freelist
)
700 scm_check_freelist (scm_freelist2
);
704 /* The rest of this is supposed to be identical to the SCM_NEWCELL
706 if (SCM_NULLP (scm_freelist2
))
708 new = scm_gc_for_newcell (&scm_master_freelist2
, &scm_freelist2
);
709 SCM_GC_SET_ALLOCATED (new);
714 scm_freelist2
= SCM_FREE_CELL_CDR (scm_freelist2
);
715 SCM_GC_SET_ALLOCATED (new);
721 #endif /* GUILE_DEBUG_FREELIST */
726 master_cells_allocated (scm_freelist_t
*master
)
728 /* the '- 1' below is to ignore the cluster spine cells. */
729 long objects
= master
->clusters_allocated
* (master
->cluster_size
- 1);
730 if (SCM_NULLP (master
->clusters
))
731 objects
-= master
->left_to_collect
;
732 return master
->span
* objects
;
736 freelist_length (SCM freelist
)
739 for (n
= 0; !SCM_NULLP (freelist
); freelist
= SCM_FREE_CELL_CDR (freelist
))
745 compute_cells_allocated ()
747 return (scm_cells_allocated
748 + master_cells_allocated (&scm_master_freelist
)
749 + master_cells_allocated (&scm_master_freelist2
)
750 - scm_master_freelist
.span
* freelist_length (scm_freelist
)
751 - scm_master_freelist2
.span
* freelist_length (scm_freelist2
));
754 /* {Scheme Interface to GC}
757 SCM_DEFINE (scm_gc_stats
, "gc-stats", 0, 0, 0,
759 "Return an association list of statistics about Guile's current\n"
761 #define FUNC_NAME s_scm_gc_stats
766 unsigned long int local_scm_mtrigger
;
767 unsigned long int local_scm_mallocated
;
768 unsigned long int local_scm_heap_size
;
769 unsigned long int local_scm_cells_allocated
;
770 unsigned long int local_scm_gc_time_taken
;
771 unsigned long int local_scm_gc_times
;
772 unsigned long int local_scm_gc_mark_time_taken
;
773 unsigned long int local_scm_gc_sweep_time_taken
;
774 double local_scm_gc_cells_swept
;
775 double local_scm_gc_cells_marked
;
785 for (i
= scm_n_heap_segs
; i
--; )
786 heap_segs
= scm_cons (scm_cons (scm_ulong2num ((unsigned long)scm_heap_table
[i
].bounds
[1]),
787 scm_ulong2num ((unsigned long)scm_heap_table
[i
].bounds
[0])),
789 if (scm_n_heap_segs
!= n
)
794 /* Below, we cons to produce the resulting list. We want a snapshot of
795 * the heap situation before consing.
797 local_scm_mtrigger
= scm_mtrigger
;
798 local_scm_mallocated
= scm_mallocated
;
799 local_scm_heap_size
= SCM_HEAP_SIZE
;
800 local_scm_cells_allocated
= compute_cells_allocated ();
801 local_scm_gc_time_taken
= scm_gc_time_taken
;
802 local_scm_gc_mark_time_taken
= scm_gc_mark_time_taken
;
803 local_scm_gc_sweep_time_taken
= scm_gc_sweep_time_taken
;
804 local_scm_gc_times
= scm_gc_times
;
805 local_scm_gc_cells_swept
= scm_gc_cells_swept_acc
;
806 local_scm_gc_cells_marked
= scm_gc_cells_marked_acc
;
808 answer
= scm_listify (scm_cons (sym_gc_time_taken
, scm_ulong2num (local_scm_gc_time_taken
)),
809 scm_cons (sym_cells_allocated
, scm_ulong2num (local_scm_cells_allocated
)),
810 scm_cons (sym_heap_size
, scm_ulong2num (local_scm_heap_size
)),
811 scm_cons (sym_mallocated
, scm_ulong2num (local_scm_mallocated
)),
812 scm_cons (sym_mtrigger
, scm_ulong2num (local_scm_mtrigger
)),
813 scm_cons (sym_times
, scm_ulong2num (local_scm_gc_times
)),
814 scm_cons (sym_gc_mark_time_taken
, scm_ulong2num (local_scm_gc_mark_time_taken
)),
815 scm_cons (sym_gc_sweep_time_taken
, scm_ulong2num (local_scm_gc_sweep_time_taken
)),
816 scm_cons (sym_cells_marked
, scm_i_dbl2big (local_scm_gc_cells_marked
)),
817 scm_cons (sym_cells_swept
, scm_i_dbl2big (local_scm_gc_cells_swept
)),
818 scm_cons (sym_heap_segments
, heap_segs
),
827 gc_start_stats (const char *what
)
829 t_before_gc
= scm_c_get_internal_run_time ();
830 scm_gc_cells_swept
= 0;
831 scm_gc_cells_collected
= 0;
832 scm_gc_yield_1
= scm_gc_yield
;
833 scm_gc_yield
= (scm_cells_allocated
834 + master_cells_allocated (&scm_master_freelist
)
835 + master_cells_allocated (&scm_master_freelist2
));
836 scm_gc_malloc_collected
= 0;
837 scm_gc_ports_collected
= 0;
844 unsigned long t
= scm_c_get_internal_run_time ();
845 scm_gc_time_taken
+= (t
- t_before_gc
);
846 scm_gc_sweep_time_taken
+= (t
- t_before_sweep
);
849 scm_gc_cells_marked_acc
+= scm_gc_cells_swept
- scm_gc_cells_collected
;
850 scm_gc_cells_swept_acc
+= scm_gc_cells_swept
;
854 SCM_DEFINE (scm_object_address
, "object-address", 1, 0, 0,
856 "Return an integer that for the lifetime of @var{obj} is uniquely\n"
857 "returned by this function for @var{obj}")
858 #define FUNC_NAME s_scm_object_address
860 return scm_ulong2num ((unsigned long) SCM_UNPACK (obj
));
865 SCM_DEFINE (scm_gc
, "gc", 0, 0, 0,
867 "Scans all of SCM objects and reclaims for further use those that are\n"
868 "no longer accessible.")
869 #define FUNC_NAME s_scm_gc
874 return SCM_UNSPECIFIED
;
880 /* {C Interface For When GC is Triggered}
884 adjust_min_yield (scm_freelist_t
*freelist
)
886 /* min yield is adjusted upwards so that next predicted total yield
887 * (allocated cells actually freed by GC) becomes
888 * `min_yield_fraction' of total heap size. Note, however, that
889 * the absolute value of min_yield will correspond to `collected'
890 * on one master (the one which currently is triggering GC).
892 * The reason why we look at total yield instead of cells collected
893 * on one list is that we want to take other freelists into account.
894 * On this freelist, we know that (local) yield = collected cells,
895 * but that's probably not the case on the other lists.
897 * (We might consider computing a better prediction, for example
898 * by computing an average over multiple GC:s.)
900 if (freelist
->min_yield_fraction
)
902 /* Pick largest of last two yields. */
903 long delta
= ((SCM_HEAP_SIZE
* freelist
->min_yield_fraction
/ 100)
904 - (long) SCM_MAX (scm_gc_yield_1
, scm_gc_yield
));
906 fprintf (stderr
, " after GC = %lu, delta = %ld\n",
907 (long) scm_cells_allocated
,
911 freelist
->min_yield
+= delta
;
916 /* When we get POSIX threads support, the master will be global and
917 * common while the freelist will be individual for each thread.
921 scm_gc_for_newcell (scm_freelist_t
*master
, SCM
*freelist
)
927 if (SCM_NULLP (master
->clusters
))
929 if (master
->grow_heap_p
|| scm_block_gc
)
931 /* In order to reduce gc frequency, try to allocate a new heap
932 * segment first, even if gc might find some free cells. If we
933 * can't obtain a new heap segment, we will try gc later.
935 master
->grow_heap_p
= 0;
936 alloc_some_heap (master
, return_on_error
);
938 if (SCM_NULLP (master
->clusters
))
940 /* The heap was not grown, either because it wasn't scheduled to
941 * grow, or because there was not enough memory available. In
942 * both cases we have to try gc to get some free cells.
945 fprintf (stderr
, "allocated = %lu, ",
946 (long) (scm_cells_allocated
947 + master_cells_allocated (&scm_master_freelist
)
948 + master_cells_allocated (&scm_master_freelist2
)));
951 adjust_min_yield (master
);
952 if (SCM_NULLP (master
->clusters
))
954 /* gc could not free any cells. Now, we _must_ allocate a
955 * new heap segment, because there is no other possibility
956 * to provide a new cell for the caller.
958 alloc_some_heap (master
, abort_on_error
);
962 cell
= SCM_CAR (master
->clusters
);
963 master
->clusters
= SCM_CDR (master
->clusters
);
964 ++master
->clusters_allocated
;
966 while (SCM_NULLP (cell
));
968 #ifdef GUILE_DEBUG_FREELIST
969 scm_check_freelist (cell
);
973 *freelist
= SCM_FREE_CELL_CDR (cell
);
979 /* This is a support routine which can be used to reserve a cluster
980 * for some special use, such as debugging. It won't be useful until
981 * free cells are preserved between garbage collections.
985 scm_alloc_cluster (scm_freelist_t
*master
)
988 cell
= scm_gc_for_newcell (master
, &freelist
);
989 SCM_SETCDR (cell
, freelist
);
995 scm_c_hook_t scm_before_gc_c_hook
;
996 scm_c_hook_t scm_before_mark_c_hook
;
997 scm_c_hook_t scm_before_sweep_c_hook
;
998 scm_c_hook_t scm_after_sweep_c_hook
;
999 scm_c_hook_t scm_after_gc_c_hook
;
1003 scm_igc (const char *what
)
1008 scm_c_hook_run (&scm_before_gc_c_hook
, 0);
1011 SCM_NULLP (scm_freelist
)
1013 : (SCM_NULLP (scm_freelist2
) ? "o" : "m"));
1015 /* During the critical section, only the current thread may run. */
1016 SCM_CRITICAL_SECTION_START
;
1018 /* fprintf (stderr, "gc: %s\n", what); */
1020 if (!scm_stack_base
|| scm_block_gc
)
1026 gc_start_stats (what
);
1028 if (scm_gc_heap_lock
)
1029 /* We've invoked the collector while a GC is already in progress.
1030 That should never happen. */
1035 /* flush dead entries from the continuation stack */
1040 elts
= SCM_VELTS (scm_continuation_stack
);
1041 bound
= SCM_VECTOR_LENGTH (scm_continuation_stack
);
1042 x
= SCM_INUM (scm_continuation_stack_ptr
);
1045 elts
[x
] = SCM_BOOL_F
;
1050 scm_c_hook_run (&scm_before_mark_c_hook
, 0);
1052 clear_mark_space ();
1056 /* Mark objects on the C stack. */
1057 SCM_FLUSH_REGISTER_WINDOWS
;
1058 /* This assumes that all registers are saved into the jmp_buf */
1059 setjmp (scm_save_regs_gc_mark
);
1060 scm_mark_locations ((SCM_STACKITEM
*) scm_save_regs_gc_mark
,
1061 ( (size_t) (sizeof (SCM_STACKITEM
) - 1 +
1062 sizeof scm_save_regs_gc_mark
)
1063 / sizeof (SCM_STACKITEM
)));
1066 size_t stack_len
= scm_stack_size (scm_stack_base
);
1067 #ifdef SCM_STACK_GROWS_UP
1068 scm_mark_locations (scm_stack_base
, stack_len
);
1070 scm_mark_locations (scm_stack_base
- stack_len
, stack_len
);
1074 #else /* USE_THREADS */
1076 /* Mark every thread's stack and registers */
1077 scm_threads_mark_stacks ();
1079 #endif /* USE_THREADS */
1081 j
= SCM_NUM_PROTECTS
;
1083 scm_gc_mark (scm_sys_protects
[j
]);
1085 /* FIXME: we should have a means to register C functions to be run
1086 * in different phases of GC
1088 scm_mark_subr_table ();
1091 scm_gc_mark (scm_root
->handle
);
1094 t_before_sweep
= scm_c_get_internal_run_time ();
1095 scm_gc_mark_time_taken
+= (t_before_sweep
- t_before_gc
);
1097 scm_c_hook_run (&scm_before_sweep_c_hook
, 0);
1101 scm_c_hook_run (&scm_after_sweep_c_hook
, 0);
1106 SCM_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
;
1143 /* A simple hack for debugging. Chose the second branch to get a
1144 meaningful backtrace for crashes inside the GC.
1147 #define goto_gc_mark_loop goto gc_mark_loop
1148 #define goto_gc_mark_nimp goto gc_mark_nimp
1150 #define goto_gc_mark_loop RECURSE(ptr); return
1151 #define goto_gc_mark_nimp RECURSE(ptr); return
1160 #ifdef MARK_DEPENDENCIES
1161 if (SCM_EQ_P (ptr
, p
))
1167 gc_mark_loop_first_time
:
1170 #if (SCM_DEBUG_CELL_ACCESSES == 1) || (defined (GUILE_DEBUG_FREELIST))
1171 /* We are in debug mode. Check the ptr exhaustively. */
1172 if (!scm_cellp (ptr
))
1173 SCM_MISC_ERROR ("rogue pointer in heap", SCM_EOL
);
1175 /* In non-debug mode, do at least some cheap testing. */
1176 if (!SCM_CELLP (ptr
))
1177 SCM_MISC_ERROR ("rogue pointer in heap", SCM_EOL
);
1180 #ifndef MARK_DEPENDENCIES
1182 if (SCM_GCMARKP (ptr
))
1185 SCM_SETGCMARK (ptr
);
1189 cell_type
= SCM_GC_CELL_TYPE (ptr
);
1190 switch (SCM_ITAG7 (cell_type
))
1192 case scm_tcs_cons_nimcar
:
1193 if (SCM_IMP (SCM_CDR (ptr
)))
1195 ptr
= SCM_CAR (ptr
);
1198 RECURSE (SCM_CAR (ptr
));
1199 ptr
= SCM_CDR (ptr
);
1201 case scm_tcs_cons_imcar
:
1202 ptr
= SCM_CDR (ptr
);
1205 RECURSE (SCM_SETTER (ptr
));
1206 ptr
= SCM_PROCEDURE (ptr
);
1208 case scm_tcs_cons_gloc
:
1210 /* Dirk:FIXME:: The following code is super ugly: ptr may be a
1211 * struct or a gloc. If it is a gloc, the cell word #0 of ptr
1212 * is the address of a scm_tc16_variable smob. If it is a
1213 * struct, the cell word #0 of ptr is a pointer to a struct
1214 * vtable data region. (The fact that these are accessed in
1215 * the same way restricts the possibilites to change the data
1216 * layout of structs or heap cells.) To discriminate between
1217 * the two, it is guaranteed that the scm_vtable_index_vcell
1218 * element of the prospective vtable is always zero. For a
1219 * gloc, this location has the CDR of the variable smob, which
1220 * is guaranteed to be non-zero.
1222 scm_bits_t word0
= SCM_CELL_WORD_0 (ptr
) - scm_tc3_cons_gloc
;
1223 scm_bits_t
* vtable_data
= (scm_bits_t
*) word0
; /* access as struct */
1224 if (vtable_data
[scm_vtable_index_vcell
] != 0)
1227 SCM gloc_car
= SCM_PACK (word0
);
1229 ptr
= SCM_CDR (ptr
);
1234 /* ptr is a struct */
1235 SCM layout
= SCM_PACK (vtable_data
[scm_vtable_index_layout
]);
1236 long len
= SCM_SYMBOL_LENGTH (layout
);
1237 char * fields_desc
= SCM_SYMBOL_CHARS (layout
);
1238 scm_bits_t
* struct_data
= (scm_bits_t
*) SCM_STRUCT_DATA (ptr
);
1240 if (vtable_data
[scm_struct_i_flags
] & SCM_STRUCTF_ENTITY
)
1242 RECURSE (SCM_PACK (struct_data
[scm_struct_i_procedure
]));
1243 RECURSE (SCM_PACK (struct_data
[scm_struct_i_setter
]));
1249 for (x
= 0; x
< len
- 2; x
+= 2, ++struct_data
)
1250 if (fields_desc
[x
] == 'p')
1251 RECURSE (SCM_PACK (*struct_data
));
1252 if (fields_desc
[x
] == 'p')
1254 if (SCM_LAYOUT_TAILP (fields_desc
[x
+ 1]))
1255 for (x
= *struct_data
++; x
; --x
, ++struct_data
)
1256 RECURSE (SCM_PACK (*struct_data
));
1258 RECURSE (SCM_PACK (*struct_data
));
1262 ptr
= SCM_PACK (vtable_data
[scm_vtable_index_vtable
]);
1267 case scm_tcs_closures
:
1268 if (SCM_IMP (SCM_ENV (ptr
)))
1270 ptr
= SCM_CLOSCAR (ptr
);
1273 RECURSE (SCM_CLOSCAR (ptr
));
1274 ptr
= SCM_ENV (ptr
);
1276 case scm_tc7_vector
:
1277 i
= SCM_VECTOR_LENGTH (ptr
);
1281 if (SCM_NIMP (SCM_VELTS (ptr
)[i
]))
1282 RECURSE (SCM_VELTS (ptr
)[i
]);
1283 ptr
= SCM_VELTS (ptr
)[0];
1288 size_t i
= SCM_CCLO_LENGTH (ptr
);
1290 for (j
= 1; j
!= i
; ++j
)
1292 SCM obj
= SCM_CCLO_REF (ptr
, j
);
1296 ptr
= SCM_CCLO_REF (ptr
, 0);
1302 case scm_tc7_byvect
:
1309 #ifdef HAVE_LONG_LONGS
1310 case scm_tc7_llvect
:
1313 case scm_tc7_string
:
1316 case scm_tc7_substring
:
1317 ptr
= SCM_CDR (ptr
);
1321 SCM_WVECT_GC_CHAIN (ptr
) = scm_weak_vectors
;
1322 scm_weak_vectors
= ptr
;
1323 if (SCM_IS_WHVEC_ANY (ptr
))
1330 len
= SCM_VECTOR_LENGTH (ptr
);
1331 weak_keys
= SCM_IS_WHVEC (ptr
) || SCM_IS_WHVEC_B (ptr
);
1332 weak_values
= SCM_IS_WHVEC_V (ptr
) || SCM_IS_WHVEC_B (ptr
);
1334 for (x
= 0; x
< len
; ++x
)
1337 alist
= SCM_VELTS (ptr
)[x
];
1339 /* mark everything on the alist except the keys or
1340 * values, according to weak_values and weak_keys. */
1341 while ( SCM_CONSP (alist
)
1342 && !SCM_GCMARKP (alist
)
1343 && SCM_CONSP (SCM_CAR (alist
)))
1348 kvpair
= SCM_CAR (alist
);
1349 next_alist
= SCM_CDR (alist
);
1352 * SCM_SETGCMARK (alist);
1353 * SCM_SETGCMARK (kvpair);
1355 * It may be that either the key or value is protected by
1356 * an escaped reference to part of the spine of this alist.
1357 * If we mark the spine here, and only mark one or neither of the
1358 * key and value, they may never be properly marked.
1359 * This leads to a horrible situation in which an alist containing
1360 * freelist cells is exported.
1362 * So only mark the spines of these arrays last of all marking.
1363 * If somebody confuses us by constructing a weak vector
1364 * with a circular alist then we are hosed, but at least we
1365 * won't prematurely drop table entries.
1368 RECURSE (SCM_CAR (kvpair
));
1370 RECURSE (SCM_CDR (kvpair
));
1373 if (SCM_NIMP (alist
))
1379 case scm_tc7_symbol
:
1380 ptr
= SCM_PROP_SLOTS (ptr
);
1385 i
= SCM_PTOBNUM (ptr
);
1386 #if (SCM_DEBUG_CELL_ACCESSES == 1) || (defined (GUILE_DEBUG_FREELIST))
1387 if (!(i
< scm_numptob
))
1388 SCM_MISC_ERROR ("undefined port type", SCM_EOL
);
1390 if (SCM_PTAB_ENTRY(ptr
))
1391 RECURSE (SCM_FILENAME (ptr
));
1392 if (scm_ptobs
[i
].mark
)
1394 ptr
= (scm_ptobs
[i
].mark
) (ptr
);
1401 switch (SCM_TYP16 (ptr
))
1402 { /* should be faster than going through scm_smobs */
1403 case scm_tc_free_cell
:
1404 /* printf("found free_cell %X ", ptr); fflush(stdout); */
1407 case scm_tc16_complex
:
1410 i
= SCM_SMOBNUM (ptr
);
1411 #if (SCM_DEBUG_CELL_ACCESSES == 1) || (defined (GUILE_DEBUG_FREELIST))
1412 if (!(i
< scm_numsmob
))
1413 SCM_MISC_ERROR ("undefined smob type", SCM_EOL
);
1415 if (scm_smobs
[i
].mark
)
1417 ptr
= (scm_smobs
[i
].mark
) (ptr
);
1425 SCM_MISC_ERROR ("unknown type", SCM_EOL
);
1431 #ifndef MARK_DEPENDENCIES
1436 /* And here we define `scm_gc_mark_dependencies', by including this
1437 * same file in itself.
1439 #define MARK scm_gc_mark_dependencies
1440 #define FNAME "scm_gc_mark_dependencies"
1441 #define MARK_DEPENDENCIES
1443 #undef MARK_DEPENDENCIES
1448 /* Mark a Region Conservatively
1452 scm_mark_locations (SCM_STACKITEM x
[], unsigned long n
)
1456 for (m
= 0; m
< n
; ++m
)
1458 SCM obj
= * (SCM
*) &x
[m
];
1459 if (SCM_CELLP (obj
))
1461 SCM_CELLPTR ptr
= SCM2PTR (obj
);
1463 long j
= scm_n_heap_segs
- 1;
1464 if (SCM_PTR_LE (scm_heap_table
[i
].bounds
[0], ptr
)
1465 && SCM_PTR_GT (scm_heap_table
[j
].bounds
[1], ptr
))
1472 || SCM_PTR_GT (scm_heap_table
[i
].bounds
[1], ptr
))
1474 else if (SCM_PTR_LE (scm_heap_table
[j
].bounds
[0], ptr
))
1482 if (SCM_PTR_GT (scm_heap_table
[k
].bounds
[1], ptr
))
1486 if (SCM_PTR_LE (scm_heap_table
[i
].bounds
[0], ptr
))
1491 else if (SCM_PTR_LE (scm_heap_table
[k
].bounds
[0], ptr
))
1495 if (SCM_PTR_GT (scm_heap_table
[j
].bounds
[1], ptr
))
1502 if (SCM_GC_IN_CARD_HEADERP (ptr
))
1505 if (scm_heap_table
[seg_id
].span
== 1
1506 || DOUBLECELL_ALIGNED_P (obj
))
1517 /* The function scm_cellp determines whether an SCM value can be regarded as a
1518 * pointer to a cell on the heap. Binary search is used in order to determine
1519 * the heap segment that contains the cell.
1522 scm_cellp (SCM value
)
1524 if (SCM_CELLP (value
)) {
1525 scm_cell
* ptr
= SCM2PTR (value
);
1526 unsigned long i
= 0;
1527 unsigned long j
= scm_n_heap_segs
- 1;
1529 if (SCM_GC_IN_CARD_HEADERP (ptr
))
1533 long k
= (i
+ j
) / 2;
1534 if (SCM_PTR_GT (scm_heap_table
[k
].bounds
[1], ptr
)) {
1536 } else if (SCM_PTR_LE (scm_heap_table
[k
].bounds
[0], ptr
)) {
1541 if (SCM_PTR_LE (scm_heap_table
[i
].bounds
[0], ptr
)
1542 && SCM_PTR_GT (scm_heap_table
[i
].bounds
[1], ptr
)
1543 && (scm_heap_table
[i
].span
== 1 || DOUBLECELL_ALIGNED_P (value
))
1544 && !SCM_GC_IN_CARD_HEADERP (ptr
)
1555 gc_sweep_freelist_start (scm_freelist_t
*freelist
)
1557 freelist
->cells
= SCM_EOL
;
1558 freelist
->left_to_collect
= freelist
->cluster_size
;
1559 freelist
->clusters_allocated
= 0;
1560 freelist
->clusters
= SCM_EOL
;
1561 freelist
->clustertail
= &freelist
->clusters
;
1562 freelist
->collected_1
= freelist
->collected
;
1563 freelist
->collected
= 0;
1567 gc_sweep_freelist_finish (scm_freelist_t
*freelist
)
1570 *freelist
->clustertail
= freelist
->cells
;
1571 if (!SCM_NULLP (freelist
->cells
))
1573 SCM c
= freelist
->cells
;
1574 SCM_SET_CELL_WORD_0 (c
, SCM_FREE_CELL_CDR (c
));
1575 SCM_SET_CELL_WORD_1 (c
, SCM_EOL
);
1576 freelist
->collected
+=
1577 freelist
->span
* (freelist
->cluster_size
- freelist
->left_to_collect
);
1579 scm_gc_cells_collected
+= freelist
->collected
;
1581 /* Although freelist->min_yield is used to test freelist->collected
1582 * (which is the local GC yield for freelist), it is adjusted so
1583 * that *total* yield is freelist->min_yield_fraction of total heap
1584 * size. This means that a too low yield is compensated by more
1585 * heap on the list which is currently doing most work, which is
1586 * just what we want.
1588 collected
= SCM_MAX (freelist
->collected_1
, freelist
->collected
);
1589 freelist
->grow_heap_p
= (collected
< freelist
->min_yield
);
1592 #define NEXT_DATA_CELL(ptr, span) \
1594 scm_cell *nxt__ = CELL_UP ((char *) (ptr) + 1, (span)); \
1595 (ptr) = (SCM_GC_IN_CARD_HEADERP (nxt__) ? \
1596 CELL_UP (SCM_GC_CELL_CARD (nxt__) + SCM_GC_CARD_N_HEADER_CELLS, span) \
1602 #define FUNC_NAME "scm_gc_sweep"
1604 register SCM_CELLPTR ptr
;
1605 register SCM nfreelist
;
1606 register scm_freelist_t
*freelist
;
1607 register unsigned long m
;
1614 gc_sweep_freelist_start (&scm_master_freelist
);
1615 gc_sweep_freelist_start (&scm_master_freelist2
);
1617 for (i
= 0; i
< scm_n_heap_segs
; i
++)
1619 register long left_to_collect
;
1622 /* Unmarked cells go onto the front of the freelist this heap
1623 segment points to. Rather than updating the real freelist
1624 pointer as we go along, we accumulate the new head in
1625 nfreelist. Then, if it turns out that the entire segment is
1626 free, we free (i.e., malloc's free) the whole segment, and
1627 simply don't assign nfreelist back into the real freelist. */
1628 freelist
= scm_heap_table
[i
].freelist
;
1629 nfreelist
= freelist
->cells
;
1630 left_to_collect
= freelist
->left_to_collect
;
1631 span
= scm_heap_table
[i
].span
;
1633 ptr
= CELL_UP (scm_heap_table
[i
].bounds
[0], span
);
1634 seg_size
= CELL_DN (scm_heap_table
[i
].bounds
[1], span
) - ptr
;
1636 /* use only data cells in seg_size */
1637 seg_size
= (seg_size
/ SCM_GC_CARD_N_CELLS
) * (SCM_GC_CARD_N_DATA_CELLS
/ span
) * span
;
1639 scm_gc_cells_swept
+= seg_size
;
1641 for (j
= seg_size
+ span
; j
-= span
; ptr
+= span
)
1645 if (SCM_GC_IN_CARD_HEADERP (ptr
))
1651 NEXT_DATA_CELL (nxt
, span
);
1658 scmptr
= PTR2SCM (ptr
);
1660 if (SCM_GCMARKP (scmptr
))
1663 switch SCM_TYP7 (scmptr
)
1665 case scm_tcs_cons_gloc
:
1667 /* Dirk:FIXME:: Again, super ugly code: scmptr may be a
1668 * struct or a gloc. See the corresponding comment in
1671 scm_bits_t word0
= (SCM_CELL_WORD_0 (scmptr
)
1672 - scm_tc3_cons_gloc
);
1673 /* access as struct */
1674 scm_bits_t
* vtable_data
= (scm_bits_t
*) word0
;
1675 if (vtable_data
[scm_vtable_index_vcell
] == 0)
1677 /* Structs need to be freed in a special order.
1678 * This is handled by GC C hooks in struct.c.
1680 SCM_SET_STRUCT_GC_CHAIN (scmptr
, scm_structs_to_free
);
1681 scm_structs_to_free
= scmptr
;
1684 /* fall through so that scmptr gets collected */
1687 case scm_tcs_cons_imcar
:
1688 case scm_tcs_cons_nimcar
:
1689 case scm_tcs_closures
:
1693 m
+= (2 + SCM_VECTOR_LENGTH (scmptr
)) * sizeof (SCM
);
1694 scm_must_free (SCM_VECTOR_BASE (scmptr
) - 2);
1696 case scm_tc7_vector
:
1698 unsigned long int length
= SCM_VECTOR_LENGTH (scmptr
);
1701 m
+= length
* sizeof (scm_bits_t
);
1702 scm_must_free (SCM_VECTOR_BASE (scmptr
));
1708 m
+= (SCM_CCLO_LENGTH (scmptr
) * sizeof (SCM
));
1709 scm_must_free (SCM_CCLO_BASE (scmptr
));
1715 unsigned long int length
= SCM_BITVECTOR_LENGTH (scmptr
);
1718 m
+= sizeof (long) * ((length
+ SCM_LONG_BIT
- 1) / SCM_LONG_BIT
);
1719 scm_must_free (SCM_BITVECTOR_BASE (scmptr
));
1723 case scm_tc7_byvect
:
1727 #ifdef HAVE_LONG_LONGS
1728 case scm_tc7_llvect
:
1733 m
+= SCM_UVECTOR_LENGTH (scmptr
) * scm_uniform_element_size (scmptr
);
1734 scm_must_free (SCM_UVECTOR_BASE (scmptr
));
1737 case scm_tc7_substring
:
1739 case scm_tc7_string
:
1740 m
+= SCM_STRING_LENGTH (scmptr
) + 1;
1741 scm_must_free (SCM_STRING_CHARS (scmptr
));
1743 case scm_tc7_symbol
:
1744 m
+= SCM_SYMBOL_LENGTH (scmptr
) + 1;
1745 scm_must_free (SCM_SYMBOL_CHARS (scmptr
));
1748 /* the various "subrs" (primitives) are never freed */
1751 if SCM_OPENP (scmptr
)
1753 int k
= SCM_PTOBNUM (scmptr
);
1754 #if (SCM_DEBUG_CELL_ACCESSES == 1) || (defined (GUILE_DEBUG_FREELIST))
1755 if (!(k
< scm_numptob
))
1756 SCM_MISC_ERROR ("undefined port type", SCM_EOL
);
1758 /* Keep "revealed" ports alive. */
1759 if (scm_revealed_count (scmptr
) > 0)
1761 /* Yes, I really do mean scm_ptobs[k].free */
1762 /* rather than ftobs[k].close. .close */
1763 /* is for explicit CLOSE-PORT by user */
1764 m
+= (scm_ptobs
[k
].free
) (scmptr
);
1765 SCM_SETSTREAM (scmptr
, 0);
1766 scm_remove_from_port_table (scmptr
);
1767 scm_gc_ports_collected
++;
1768 SCM_CLR_PORT_OPEN_FLAG (scmptr
);
1772 switch SCM_TYP16 (scmptr
)
1774 case scm_tc_free_cell
:
1779 m
+= (SCM_NUMDIGS (scmptr
) * SCM_BITSPERDIG
/ SCM_CHAR_BIT
);
1780 scm_must_free (SCM_BDIGITS (scmptr
));
1782 #endif /* def SCM_BIGDIG */
1783 case scm_tc16_complex
:
1784 m
+= sizeof (scm_complex_t
);
1785 scm_must_free (SCM_COMPLEX_MEM (scmptr
));
1790 k
= SCM_SMOBNUM (scmptr
);
1791 #if (SCM_DEBUG_CELL_ACCESSES == 1) || (defined (GUILE_DEBUG_FREELIST))
1792 if (!(k
< scm_numsmob
))
1793 SCM_MISC_ERROR ("undefined smob type", SCM_EOL
);
1795 if (scm_smobs
[k
].free
)
1796 m
+= (scm_smobs
[k
].free
) (scmptr
);
1802 SCM_MISC_ERROR ("unknown type", SCM_EOL
);
1805 if (!--left_to_collect
)
1807 SCM_SET_CELL_WORD_0 (scmptr
, nfreelist
);
1808 *freelist
->clustertail
= scmptr
;
1809 freelist
->clustertail
= SCM_CDRLOC (scmptr
);
1811 nfreelist
= SCM_EOL
;
1812 freelist
->collected
+= span
* freelist
->cluster_size
;
1813 left_to_collect
= freelist
->cluster_size
;
1817 /* Stick the new cell on the front of nfreelist. It's
1818 critical that we mark this cell as freed; otherwise, the
1819 conservative collector might trace it as some other type
1821 SCM_SET_CELL_TYPE (scmptr
, scm_tc_free_cell
);
1822 SCM_SET_FREE_CELL_CDR (scmptr
, nfreelist
);
1827 #ifdef GC_FREE_SEGMENTS
1832 freelist
->heap_size
-= seg_size
;
1833 free ((char *) scm_heap_table
[i
].bounds
[0]);
1834 scm_heap_table
[i
].bounds
[0] = 0;
1835 for (j
= i
+ 1; j
< scm_n_heap_segs
; j
++)
1836 scm_heap_table
[j
- 1] = scm_heap_table
[j
];
1837 scm_n_heap_segs
-= 1;
1838 i
--; /* We need to scan the segment just moved. */
1841 #endif /* ifdef GC_FREE_SEGMENTS */
1843 /* Update the real freelist pointer to point to the head of
1844 the list of free cells we've built for this segment. */
1845 freelist
->cells
= nfreelist
;
1846 freelist
->left_to_collect
= left_to_collect
;
1849 #ifdef GUILE_DEBUG_FREELIST
1850 scm_map_free_list ();
1854 gc_sweep_freelist_finish (&scm_master_freelist
);
1855 gc_sweep_freelist_finish (&scm_master_freelist2
);
1857 /* When we move to POSIX threads private freelists should probably
1858 be GC-protected instead. */
1859 scm_freelist
= SCM_EOL
;
1860 scm_freelist2
= SCM_EOL
;
1862 scm_cells_allocated
= (SCM_HEAP_SIZE
- scm_gc_cells_collected
);
1863 scm_gc_yield
-= scm_cells_allocated
;
1865 if (scm_mallocated
< m
)
1866 /* The byte count of allocated objects has underflowed. This is
1867 probably because you forgot to report the sizes of objects you
1868 have allocated, by calling scm_done_malloc or some such. When
1869 the GC freed them, it subtracted their size from
1870 scm_mallocated, which underflowed. */
1873 scm_mallocated
-= m
;
1874 scm_gc_malloc_collected
= m
;
1880 /* {Front end to malloc}
1882 * scm_must_malloc, scm_must_realloc, scm_must_free, scm_done_malloc,
1885 * These functions provide services comparable to malloc, realloc, and
1886 * free. They should be used when allocating memory that will be under
1887 * control of the garbage collector, i.e., if the memory may be freed
1888 * during garbage collection.
1892 * Return newly malloced storage or throw an error.
1894 * The parameter WHAT is a string for error reporting.
1895 * If the threshold scm_mtrigger will be passed by this
1896 * allocation, or if the first call to malloc fails,
1897 * garbage collect -- on the presumption that some objects
1898 * using malloced storage may be collected.
1900 * The limit scm_mtrigger may be raised by this allocation.
1903 scm_must_malloc (size_t size
, const char *what
)
1906 unsigned long nm
= scm_mallocated
+ size
;
1909 /* The byte count of allocated objects has overflowed. This is
1910 probably because you forgot to report the correct size of freed
1911 memory in some of your smob free methods. */
1914 if (nm
<= scm_mtrigger
)
1916 SCM_SYSCALL (ptr
= malloc (size
));
1919 scm_mallocated
= nm
;
1920 #ifdef GUILE_DEBUG_MALLOC
1921 scm_malloc_register (ptr
, what
);
1929 nm
= scm_mallocated
+ size
;
1932 /* The byte count of allocated objects has overflowed. This is
1933 probably because you forgot to report the correct size of freed
1934 memory in some of your smob free methods. */
1937 SCM_SYSCALL (ptr
= malloc (size
));
1940 scm_mallocated
= nm
;
1941 if (nm
> scm_mtrigger
- SCM_MTRIGGER_HYSTERESIS
) {
1942 if (nm
> scm_mtrigger
)
1943 scm_mtrigger
= nm
+ nm
/ 2;
1945 scm_mtrigger
+= scm_mtrigger
/ 2;
1947 #ifdef GUILE_DEBUG_MALLOC
1948 scm_malloc_register (ptr
, what
);
1954 scm_memory_error (what
);
1959 * is similar to scm_must_malloc.
1962 scm_must_realloc (void *where
,
1970 if (size
<= old_size
)
1973 nm
= scm_mallocated
+ size
- old_size
;
1975 if (nm
< (size
- old_size
))
1976 /* The byte count of allocated objects has overflowed. This is
1977 probably because you forgot to report the correct size of freed
1978 memory in some of your smob free methods. */
1981 if (nm
<= scm_mtrigger
)
1983 SCM_SYSCALL (ptr
= realloc (where
, size
));
1986 scm_mallocated
= nm
;
1987 #ifdef GUILE_DEBUG_MALLOC
1988 scm_malloc_reregister (where
, ptr
, what
);
1996 nm
= scm_mallocated
+ size
- old_size
;
1998 if (nm
< (size
- old_size
))
1999 /* The byte count of allocated objects has overflowed. This is
2000 probably because you forgot to report the correct size of freed
2001 memory in some of your smob free methods. */
2004 SCM_SYSCALL (ptr
= realloc (where
, size
));
2007 scm_mallocated
= nm
;
2008 if (nm
> scm_mtrigger
- SCM_MTRIGGER_HYSTERESIS
) {
2009 if (nm
> scm_mtrigger
)
2010 scm_mtrigger
= nm
+ nm
/ 2;
2012 scm_mtrigger
+= scm_mtrigger
/ 2;
2014 #ifdef GUILE_DEBUG_MALLOC
2015 scm_malloc_reregister (where
, ptr
, what
);
2020 scm_memory_error (what
);
2024 scm_must_strndup (const char *str
, size_t length
)
2026 char * dst
= scm_must_malloc (length
+ 1, "scm_must_strndup");
2027 memcpy (dst
, str
, length
);
2033 scm_must_strdup (const char *str
)
2035 return scm_must_strndup (str
, strlen (str
));
2039 scm_must_free (void *obj
)
2040 #define FUNC_NAME "scm_must_free"
2042 #ifdef GUILE_DEBUG_MALLOC
2043 scm_malloc_unregister (obj
);
2048 SCM_MISC_ERROR ("freeing NULL pointer", SCM_EOL
);
2053 /* Announce that there has been some malloc done that will be freed
2054 * during gc. A typical use is for a smob that uses some malloced
2055 * memory but can not get it from scm_must_malloc (for whatever
2056 * reason). When a new object of this smob is created you call
2057 * scm_done_malloc with the size of the object. When your smob free
2058 * function is called, be sure to include this size in the return
2061 * If you can't actually free the memory in the smob free function,
2062 * for whatever reason (like reference counting), you still can (and
2063 * should) report the amount of memory freed when you actually free it.
2064 * Do it by calling scm_done_malloc with the _negated_ size. Clever,
2065 * eh? Or even better, call scm_done_free. */
2068 scm_done_malloc (long size
)
2071 if (scm_mallocated
< size
)
2072 /* The byte count of allocated objects has underflowed. This is
2073 probably because you forgot to report the sizes of objects you
2074 have allocated, by calling scm_done_malloc or some such. When
2075 the GC freed them, it subtracted their size from
2076 scm_mallocated, which underflowed. */
2079 unsigned long nm
= scm_mallocated
+ size
;
2081 /* The byte count of allocated objects has overflowed. This is
2082 probably because you forgot to report the correct size of freed
2083 memory in some of your smob free methods. */
2087 scm_mallocated
+= size
;
2089 if (scm_mallocated
> scm_mtrigger
)
2091 scm_igc ("foreign mallocs");
2092 if (scm_mallocated
> scm_mtrigger
- SCM_MTRIGGER_HYSTERESIS
)
2094 if (scm_mallocated
> scm_mtrigger
)
2095 scm_mtrigger
= scm_mallocated
+ scm_mallocated
/ 2;
2097 scm_mtrigger
+= scm_mtrigger
/ 2;
2103 scm_done_free (long size
)
2106 if (scm_mallocated
< size
)
2107 /* The byte count of allocated objects has underflowed. This is
2108 probably because you forgot to report the sizes of objects you
2109 have allocated, by calling scm_done_malloc or some such. When
2110 the GC freed them, it subtracted their size from
2111 scm_mallocated, which underflowed. */
2114 unsigned long nm
= scm_mallocated
+ size
;
2116 /* The byte count of allocated objects has overflowed. This is
2117 probably because you forgot to report the correct size of freed
2118 memory in some of your smob free methods. */
2122 scm_mallocated
-= size
;
2129 * Each heap segment is an array of objects of a particular size.
2130 * Every segment has an associated (possibly shared) freelist.
2131 * A table of segment records is kept that records the upper and
2132 * lower extents of the segment; this is used during the conservative
2133 * phase of gc to identify probably gc roots (because they point
2134 * into valid segments at reasonable offsets). */
2137 * is true if the first segment was smaller than INIT_HEAP_SEG.
2138 * If scm_expmem is set to one, subsequent segment allocations will
2139 * allocate segments of size SCM_EXPHEAP(scm_heap_size).
2143 size_t scm_max_segment_size
;
2146 * is the lowest base address of any heap segment.
2148 SCM_CELLPTR scm_heap_org
;
2150 scm_heap_seg_data_t
* scm_heap_table
= 0;
2151 static size_t heap_segment_table_size
= 0;
2152 size_t scm_n_heap_segs
= 0;
2155 * initializes a new heap segment and returns the number of objects it contains.
2157 * The segment origin and segment size in bytes are input parameters.
2158 * The freelist is both input and output.
2160 * This function presumes that the scm_heap_table has already been expanded
2161 * to accomodate a new segment record and that the markbit space was reserved
2162 * for all the cards in this segment.
2165 #define INIT_CARD(card, span) \
2167 SCM_GC_SET_CARD_BVEC (card, get_bvec ()); \
2169 SCM_GC_SET_CARD_DOUBLECELL (card); \
2173 init_heap_seg (SCM_CELLPTR seg_org
, size_t size
, scm_freelist_t
*freelist
)
2175 register SCM_CELLPTR ptr
;
2176 SCM_CELLPTR seg_end
;
2178 ptrdiff_t n_new_cells
;
2179 int span
= freelist
->span
;
2181 if (seg_org
== NULL
)
2184 /* Align the begin ptr up.
2186 ptr
= SCM_GC_CARD_UP (seg_org
);
2188 /* Compute the ceiling on valid object pointers w/in this segment.
2190 seg_end
= SCM_GC_CARD_DOWN ((char *)seg_org
+ size
);
2192 /* Find the right place and insert the segment record.
2195 for (new_seg_index
= 0;
2196 ( (new_seg_index
< scm_n_heap_segs
)
2197 && SCM_PTR_LE (scm_heap_table
[new_seg_index
].bounds
[0], seg_org
));
2203 for (i
= scm_n_heap_segs
; i
> new_seg_index
; --i
)
2204 scm_heap_table
[i
] = scm_heap_table
[i
- 1];
2209 scm_heap_table
[new_seg_index
].span
= span
;
2210 scm_heap_table
[new_seg_index
].freelist
= freelist
;
2211 scm_heap_table
[new_seg_index
].bounds
[0] = ptr
;
2212 scm_heap_table
[new_seg_index
].bounds
[1] = seg_end
;
2215 n_new_cells
= seg_end
- ptr
;
2217 freelist
->heap_size
+= n_new_cells
;
2219 /* Partition objects in this segment into clusters */
2222 SCM
*clusterp
= &clusters
;
2224 NEXT_DATA_CELL (ptr
, span
);
2225 while (ptr
< seg_end
)
2227 scm_cell
*nxt
= ptr
;
2228 scm_cell
*prv
= NULL
;
2229 scm_cell
*last_card
= NULL
;
2230 int n_data_cells
= (SCM_GC_CARD_N_DATA_CELLS
/ span
) * SCM_CARDS_PER_CLUSTER
- 1;
2231 NEXT_DATA_CELL(nxt
, span
);
2233 /* Allocate cluster spine
2235 *clusterp
= PTR2SCM (ptr
);
2236 SCM_SETCAR (*clusterp
, PTR2SCM (nxt
));
2237 clusterp
= SCM_CDRLOC (*clusterp
);
2240 while (n_data_cells
--)
2242 scm_cell
*card
= SCM_GC_CELL_CARD (ptr
);
2243 SCM scmptr
= PTR2SCM (ptr
);
2245 NEXT_DATA_CELL (nxt
, span
);
2248 if (card
!= last_card
)
2250 INIT_CARD (card
, span
);
2254 SCM_SET_CELL_TYPE (scmptr
, scm_tc_free_cell
);
2255 SCM_SET_FREE_CELL_CDR (scmptr
, PTR2SCM (nxt
));
2260 SCM_SET_FREE_CELL_CDR (PTR2SCM (prv
), SCM_EOL
);
2265 scm_cell
*ref
= seg_end
;
2266 NEXT_DATA_CELL (ref
, span
);
2268 /* [cmm] looks like the segment size doesn't divide cleanly by
2269 cluster size. bad cmm! */
2273 /* Patch up the last cluster pointer in the segment
2274 * to join it to the input freelist.
2276 *clusterp
= freelist
->clusters
;
2277 freelist
->clusters
= clusters
;
2281 fprintf (stderr
, "H");
2287 round_to_cluster_size (scm_freelist_t
*freelist
, size_t len
)
2289 size_t cluster_size_in_bytes
= CLUSTER_SIZE_IN_BYTES (freelist
);
2292 (len
+ cluster_size_in_bytes
- 1) / cluster_size_in_bytes
* cluster_size_in_bytes
2293 + ALIGNMENT_SLACK (freelist
);
2297 alloc_some_heap (scm_freelist_t
*freelist
, policy_on_error error_policy
)
2298 #define FUNC_NAME "alloc_some_heap"
2303 if (scm_gc_heap_lock
)
2305 /* Critical code sections (such as the garbage collector) aren't
2306 * supposed to add heap segments.
2308 fprintf (stderr
, "alloc_some_heap: Can not extend locked heap.\n");
2312 if (scm_n_heap_segs
== heap_segment_table_size
)
2314 /* We have to expand the heap segment table to have room for the new
2315 * segment. Do not yet increment scm_n_heap_segs -- that is done by
2316 * init_heap_seg only if the allocation of the segment itself succeeds.
2318 size_t new_table_size
= scm_n_heap_segs
+ 1;
2319 size_t size
= new_table_size
* sizeof (scm_heap_seg_data_t
);
2320 scm_heap_seg_data_t
*new_heap_table
;
2322 SCM_SYSCALL (new_heap_table
= ((scm_heap_seg_data_t
*)
2323 realloc ((char *)scm_heap_table
, size
)));
2324 if (!new_heap_table
)
2326 if (error_policy
== abort_on_error
)
2328 fprintf (stderr
, "alloc_some_heap: Could not grow heap segment table.\n");
2338 scm_heap_table
= new_heap_table
;
2339 heap_segment_table_size
= new_table_size
;
2343 /* Pick a size for the new heap segment.
2344 * The rule for picking the size of a segment is explained in
2348 /* Assure that the new segment is predicted to be large enough.
2350 * New yield should at least equal GC fraction of new heap size, i.e.
2352 * y + dh > f * (h + dh)
2355 * f : min yield fraction
2357 * dh : size of new heap segment
2359 * This gives dh > (f * h - y) / (1 - f)
2361 int f
= freelist
->min_yield_fraction
;
2362 unsigned long h
= SCM_HEAP_SIZE
;
2363 size_t min_cells
= (f
* h
- 100 * (long) scm_gc_yield
) / (99 - f
);
2364 len
= SCM_EXPHEAP (freelist
->heap_size
);
2366 fprintf (stderr
, "(%ld < %ld)", (long) len
, (long) min_cells
);
2368 if (len
< min_cells
)
2369 len
= min_cells
+ freelist
->cluster_size
;
2370 len
*= sizeof (scm_cell
);
2371 /* force new sampling */
2372 freelist
->collected
= LONG_MAX
;
2375 if (len
> scm_max_segment_size
)
2376 len
= scm_max_segment_size
;
2381 smallest
= CLUSTER_SIZE_IN_BYTES (freelist
);
2386 /* Allocate with decaying ambition. */
2387 while ((len
>= SCM_MIN_HEAP_SEG_SIZE
)
2388 && (len
>= smallest
))
2390 size_t rounded_len
= round_to_cluster_size (freelist
, len
);
2391 SCM_SYSCALL (ptr
= (SCM_CELLPTR
) malloc (rounded_len
));
2394 init_heap_seg (ptr
, rounded_len
, freelist
);
2401 if (error_policy
== abort_on_error
)
2403 fprintf (stderr
, "alloc_some_heap: Could not grow heap.\n");
2410 /* {GC Protection Helper Functions}
2415 * If within a function you need to protect one or more scheme objects from
2416 * garbage collection, pass them as parameters to one of the
2417 * scm_remember_upto_here* functions below. These functions don't do
2418 * anything, but since the compiler does not know that they are actually
2419 * no-ops, it will generate code that calls these functions with the given
2420 * parameters. Therefore, you can be sure that the compiler will keep those
2421 * scheme values alive (on the stack or in a register) up to the point where
2422 * scm_remember_upto_here* is called. In other words, place the call to
2423 * scm_remember_upt_here* _behind_ the last code in your function, that
2424 * depends on the scheme object to exist.
2426 * Example: We want to make sure, that the string object str does not get
2427 * garbage collected during the execution of 'some_function', because
2428 * otherwise the characters belonging to str would be freed and
2429 * 'some_function' might access freed memory. To make sure that the compiler
2430 * keeps str alive on the stack or in a register such that it is visible to
2431 * the conservative gc we add the call to scm_remember_upto_here_1 _after_ the
2432 * call to 'some_function'. Note that this would not be necessary if str was
2433 * used anyway after the call to 'some_function'.
2434 * char *chars = SCM_STRING_CHARS (str);
2435 * some_function (chars);
2436 * scm_remember_upto_here_1 (str); // str will be alive up to this point.
2440 scm_remember_upto_here_1 (SCM obj
)
2442 /* Empty. Protects a single object from garbage collection. */
2446 scm_remember_upto_here_2 (SCM obj1
, SCM obj2
)
2448 /* Empty. Protects two objects from garbage collection. */
2452 scm_remember_upto_here (SCM obj
, ...)
2454 /* Empty. Protects any number of objects from garbage collection. */
2458 #if (SCM_DEBUG_DEPRECATED == 0)
2461 scm_remember (SCM
*ptr
)
2463 scm_c_issue_deprecation_warning ("`scm_remember' is deprecated. "
2464 "Use the `scm_remember_upto_here*' family of functions instead.");
2467 #endif /* SCM_DEBUG_DEPRECATED == 0 */
2470 These crazy functions prevent garbage collection
2471 of arguments after the first argument by
2472 ensuring they remain live throughout the
2473 function because they are used in the last
2474 line of the code block.
2475 It'd be better to have a nice compiler hint to
2476 aid the conservative stack-scanning GC. --03/09/00 gjb */
2478 scm_return_first (SCM elt
, ...)
2484 scm_return_first_int (int i
, ...)
2491 scm_permanent_object (SCM obj
)
2494 scm_permobjs
= scm_cons (obj
, scm_permobjs
);
2500 /* Protect OBJ from the garbage collector. OBJ will not be freed, even if all
2501 other references are dropped, until the object is unprotected by calling
2502 scm_unprotect_object (OBJ). Calls to scm_protect/unprotect_object nest,
2503 i. e. it is possible to protect the same object several times, but it is
2504 necessary to unprotect the object the same number of times to actually get
2505 the object unprotected. It is an error to unprotect an object more often
2506 than it has been protected before. The function scm_protect_object returns
2510 /* Implementation note: For every object X, there is a counter which
2511 scm_protect_object(X) increments and scm_unprotect_object(X) decrements.
2515 scm_protect_object (SCM obj
)
2519 /* This critical section barrier will be replaced by a mutex. */
2522 handle
= scm_hashq_create_handle_x (scm_protects
, obj
, SCM_MAKINUM (0));
2523 SCM_SETCDR (handle
, scm_sum (SCM_CDR (handle
), SCM_MAKINUM (1)));
2531 /* Remove any protection for OBJ established by a prior call to
2532 scm_protect_object. This function returns OBJ.
2534 See scm_protect_object for more information. */
2536 scm_unprotect_object (SCM obj
)
2540 /* This critical section barrier will be replaced by a mutex. */
2543 handle
= scm_hashq_get_handle (scm_protects
, obj
);
2545 if (SCM_FALSEP (handle
))
2547 fprintf (stderr
, "scm_unprotect_object called on unprotected object\n");
2552 SCM count
= scm_difference (SCM_CDR (handle
), SCM_MAKINUM (1));
2553 if (SCM_EQ_P (count
, SCM_MAKINUM (0)))
2554 scm_hashq_remove_x (scm_protects
, obj
);
2556 SCM_SETCDR (handle
, count
);
2566 /* called on process termination. */
2572 extern int on_exit (void (*procp
) (), int arg
);
2575 cleanup (int status
, void *arg
)
2577 #error Dont know how to setup a cleanup handler on your system.
2582 scm_flush_all_ports ();
2587 make_initial_segment (size_t init_heap_size
, scm_freelist_t
*freelist
)
2589 size_t rounded_size
= round_to_cluster_size (freelist
, init_heap_size
);
2591 if (!init_heap_seg ((SCM_CELLPTR
) malloc (rounded_size
),
2595 rounded_size
= round_to_cluster_size (freelist
, SCM_HEAP_SEG_SIZE
);
2596 if (!init_heap_seg ((SCM_CELLPTR
) malloc (rounded_size
),
2604 if (freelist
->min_yield_fraction
)
2605 freelist
->min_yield
= (freelist
->heap_size
* freelist
->min_yield_fraction
2607 freelist
->grow_heap_p
= (freelist
->heap_size
< freelist
->min_yield
);
2614 init_freelist (scm_freelist_t
*freelist
,
2619 freelist
->clusters
= SCM_EOL
;
2620 freelist
->cluster_size
= cluster_size
+ 1;
2621 freelist
->left_to_collect
= 0;
2622 freelist
->clusters_allocated
= 0;
2623 freelist
->min_yield
= 0;
2624 freelist
->min_yield_fraction
= min_yield
;
2625 freelist
->span
= span
;
2626 freelist
->collected
= 0;
2627 freelist
->collected_1
= 0;
2628 freelist
->heap_size
= 0;
2632 /* Get an integer from an environment variable. */
2634 scm_i_getenv_int (const char *var
, int def
)
2636 char *end
, *val
= getenv (var
);
2640 res
= strtol (val
, &end
, 10);
2650 unsigned long gc_trigger_1
;
2651 unsigned long gc_trigger_2
;
2652 size_t init_heap_size_1
;
2653 size_t init_heap_size_2
;
2656 #if (SCM_DEBUG_CELL_ACCESSES == 1)
2657 scm_tc16_allocated
= scm_make_smob_type ("allocated cell", 0);
2658 #endif /* SCM_DEBUG_CELL_ACCESSES == 1 */
2660 j
= SCM_NUM_PROTECTS
;
2662 scm_sys_protects
[--j
] = SCM_BOOL_F
;
2665 scm_freelist
= SCM_EOL
;
2666 scm_freelist2
= SCM_EOL
;
2667 gc_trigger_1
= scm_i_getenv_int ("GUILE_MIN_YIELD_1", scm_default_min_yield_1
);
2668 init_freelist (&scm_master_freelist
, 1, SCM_CLUSTER_SIZE_1
, gc_trigger_1
);
2669 gc_trigger_2
= scm_i_getenv_int ("GUILE_MIN_YIELD_2", scm_default_min_yield_2
);
2670 init_freelist (&scm_master_freelist2
, 2, SCM_CLUSTER_SIZE_2
, gc_trigger_2
);
2671 scm_max_segment_size
= scm_i_getenv_int ("GUILE_MAX_SEGMENT_SIZE", scm_default_max_segment_size
);
2675 j
= SCM_HEAP_SEG_SIZE
;
2676 scm_mtrigger
= SCM_INIT_MALLOC_LIMIT
;
2677 scm_heap_table
= ((scm_heap_seg_data_t
*)
2678 scm_must_malloc (sizeof (scm_heap_seg_data_t
) * 2, "hplims"));
2679 heap_segment_table_size
= 2;
2681 mark_space_ptr
= &mark_space_head
;
2683 init_heap_size_1
= scm_i_getenv_int ("GUILE_INIT_SEGMENT_SIZE_1", scm_default_init_heap_size_1
);
2684 init_heap_size_2
= scm_i_getenv_int ("GUILE_INIT_SEGMENT_SIZE_2", scm_default_init_heap_size_2
);
2685 if (make_initial_segment (init_heap_size_1
, &scm_master_freelist
) ||
2686 make_initial_segment (init_heap_size_2
, &scm_master_freelist2
))
2689 /* scm_hplims[0] can change. do not remove scm_heap_org */
2690 scm_heap_org
= CELL_UP (scm_heap_table
[0].bounds
[0], 1);
2692 scm_c_hook_init (&scm_before_gc_c_hook
, 0, SCM_C_HOOK_NORMAL
);
2693 scm_c_hook_init (&scm_before_mark_c_hook
, 0, SCM_C_HOOK_NORMAL
);
2694 scm_c_hook_init (&scm_before_sweep_c_hook
, 0, SCM_C_HOOK_NORMAL
);
2695 scm_c_hook_init (&scm_after_sweep_c_hook
, 0, SCM_C_HOOK_NORMAL
);
2696 scm_c_hook_init (&scm_after_gc_c_hook
, 0, SCM_C_HOOK_NORMAL
);
2698 /* Initialise the list of ports. */
2699 scm_port_table
= (scm_port_t
**)
2700 malloc (sizeof (scm_port_t
*) * scm_port_table_room
);
2701 if (!scm_port_table
)
2708 on_exit (cleanup
, 0);
2712 scm_stand_in_procs
= SCM_EOL
;
2713 scm_permobjs
= SCM_EOL
;
2714 scm_protects
= scm_c_make_hash_table (31);
2721 SCM scm_after_gc_hook
;
2723 static SCM gc_async
;
2725 /* The function gc_async_thunk causes the execution of the after-gc-hook. It
2726 * is run after the gc, as soon as the asynchronous events are handled by the
2730 gc_async_thunk (void)
2732 scm_c_run_hook (scm_after_gc_hook
, SCM_EOL
);
2733 return SCM_UNSPECIFIED
;
2737 /* The function mark_gc_async is run by the scm_after_gc_c_hook at the end of
2738 * the garbage collection. The only purpose of this function is to mark the
2739 * gc_async (which will eventually lead to the execution of the
2743 mark_gc_async (void * hook_data
, void *func_data
, void *data
)
2745 scm_system_async_mark (gc_async
);
2755 /* Dirk:FIXME:: scm_create_hook is strange. */
2756 scm_after_gc_hook
= scm_create_hook ("after-gc-hook", 0);
2758 after_gc_thunk
= scm_c_make_subr ("%gc-thunk", scm_tc7_subr_0
,
2760 gc_async
= scm_system_async (after_gc_thunk
); /* protected via scm_asyncs */
2762 scm_c_hook_add (&scm_after_gc_c_hook
, mark_gc_async
, NULL
, 0);
2764 #ifndef SCM_MAGIC_SNARFER
2765 #include "libguile/gc.x"
2769 #endif /*MARK_DEPENDENCIES*/