Commit | Line | Data |
---|---|---|
85d7012e | 1 | /* Copyright (C) 1995,1996,1997,1998,1999,2000,2001, 2002, 2003, 2006, 2008, 2009 Free Software Foundation, Inc. |
a00c95d9 | 2 | * |
73be1d9e | 3 | * This library is free software; you can redistribute it and/or |
53befeb7 NJ |
4 | * modify it under the terms of the GNU Lesser General Public License |
5 | * as published by the Free Software Foundation; either version 3 of | |
6 | * the License, or (at your option) any later version. | |
a00c95d9 | 7 | * |
53befeb7 NJ |
8 | * This library is distributed in the hope that it will be useful, but |
9 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
73be1d9e MV |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
11 | * Lesser General Public License for more details. | |
a00c95d9 | 12 | * |
73be1d9e MV |
13 | * You should have received a copy of the GNU Lesser General Public |
14 | * License along with this library; if not, write to the Free Software | |
53befeb7 NJ |
15 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA |
16 | * 02110-1301 USA | |
73be1d9e | 17 | */ |
1bbd0b84 | 18 | |
37ddcaf6 MD |
19 | /* #define DEBUGINFO */ |
20 | ||
dbb605f5 | 21 | #ifdef HAVE_CONFIG_H |
aa54a9b0 RB |
22 | # include <config.h> |
23 | #endif | |
56495472 | 24 | |
e7bca227 LC |
25 | #include "libguile/gen-scmconfig.h" |
26 | ||
0f2d19dd | 27 | #include <stdio.h> |
e6e2e95a | 28 | #include <errno.h> |
783e7774 | 29 | #include <string.h> |
c8a1bdc4 | 30 | #include <assert.h> |
e6e2e95a | 31 | |
3ec17f28 LC |
32 | #ifdef __ia64__ |
33 | #include <ucontext.h> | |
34 | extern unsigned long * __libc_ia64_register_backing_store_base; | |
35 | #endif | |
36 | ||
a0599745 | 37 | #include "libguile/_scm.h" |
0a7a7445 | 38 | #include "libguile/eval.h" |
a0599745 MD |
39 | #include "libguile/stime.h" |
40 | #include "libguile/stackchk.h" | |
41 | #include "libguile/struct.h" | |
a0599745 | 42 | #include "libguile/smob.h" |
2fa901a5 | 43 | #include "libguile/arrays.h" |
a0599745 MD |
44 | #include "libguile/async.h" |
45 | #include "libguile/ports.h" | |
46 | #include "libguile/root.h" | |
47 | #include "libguile/strings.h" | |
48 | #include "libguile/vectors.h" | |
801cb5e7 | 49 | #include "libguile/weaks.h" |
686765af | 50 | #include "libguile/hashtab.h" |
ecf470a2 | 51 | #include "libguile/tags.h" |
a0599745 | 52 | |
c8a1bdc4 | 53 | #include "libguile/private-gc.h" |
a0599745 | 54 | #include "libguile/validate.h" |
1be6b49c | 55 | #include "libguile/deprecation.h" |
a0599745 | 56 | #include "libguile/gc.h" |
9de87eea | 57 | #include "libguile/dynwind.h" |
fce59c93 | 58 | |
1c44468d | 59 | #include "libguile/bdw-gc.h" |
a82e7953 | 60 | |
bc9d9bb2 | 61 | #ifdef GUILE_DEBUG_MALLOC |
a0599745 | 62 | #include "libguile/debug-malloc.h" |
bc9d9bb2 MD |
63 | #endif |
64 | ||
0f2d19dd | 65 | #ifdef HAVE_MALLOC_H |
95b88819 | 66 | #include <malloc.h> |
0f2d19dd JB |
67 | #endif |
68 | ||
69 | #ifdef HAVE_UNISTD_H | |
95b88819 | 70 | #include <unistd.h> |
0f2d19dd JB |
71 | #endif |
72 | ||
fb50ef08 MD |
73 | /* Lock this mutex before doing lazy sweeping. |
74 | */ | |
b17e0ac3 | 75 | scm_i_pthread_mutex_t scm_i_sweep_mutex = SCM_I_PTHREAD_MUTEX_INITIALIZER; |
fb50ef08 | 76 | |
eae33935 | 77 | /* Set this to != 0 if every cell that is accessed shall be checked: |
61045190 | 78 | */ |
eab1b259 HWN |
79 | int scm_debug_cell_accesses_p = 0; |
80 | int scm_expensive_debug_cell_accesses_p = 0; | |
406c7d90 | 81 | |
e81d98ec DH |
82 | /* Set this to 0 if no additional gc's shall be performed, otherwise set it to |
83 | * the number of cell accesses after which a gc shall be called. | |
84 | */ | |
eab1b259 | 85 | int scm_debug_cells_gc_interval = 0; |
e81d98ec | 86 | |
eab1b259 HWN |
87 | /* |
88 | Global variable, so you can switch it off at runtime by setting | |
89 | scm_i_cell_validation_already_running. | |
406c7d90 | 90 | */ |
eab1b259 HWN |
91 | int scm_i_cell_validation_already_running ; |
92 | ||
93 | #if (SCM_DEBUG_CELL_ACCESSES == 1) | |
94 | ||
95 | ||
96 | /* | |
97 | ||
98 | Assert that the given object is a valid reference to a valid cell. This | |
99 | test involves to determine whether the object is a cell pointer, whether | |
100 | this pointer actually points into a heap segment and whether the cell | |
101 | pointed to is not a free cell. Further, additional garbage collections may | |
102 | get executed after a user defined number of cell accesses. This helps to | |
103 | find places in the C code where references are dropped for extremely short | |
104 | periods. | |
105 | ||
106 | */ | |
406c7d90 | 107 | void |
eab1b259 | 108 | scm_i_expensive_validation_check (SCM cell) |
406c7d90 | 109 | { |
eab1b259 HWN |
110 | /* If desired, perform additional garbage collections after a user |
111 | * defined number of cell accesses. | |
112 | */ | |
113 | if (scm_debug_cells_gc_interval) | |
114 | { | |
115 | static unsigned int counter = 0; | |
61045190 | 116 | |
eab1b259 HWN |
117 | if (counter != 0) |
118 | { | |
119 | --counter; | |
120 | } | |
121 | else | |
122 | { | |
123 | counter = scm_debug_cells_gc_interval; | |
b17e0ac3 | 124 | scm_gc (); |
eab1b259 HWN |
125 | } |
126 | } | |
127 | } | |
128 | ||
129 | void | |
130 | scm_assert_cell_valid (SCM cell) | |
131 | { | |
132 | if (!scm_i_cell_validation_already_running && scm_debug_cell_accesses_p) | |
406c7d90 | 133 | { |
eab1b259 | 134 | scm_i_cell_validation_already_running = 1; /* set to avoid recursion */ |
406c7d90 | 135 | |
c8a1bdc4 | 136 | /* |
eab1b259 HWN |
137 | During GC, no user-code should be run, and the guile core |
138 | should use non-protected accessors. | |
139 | */ | |
c8a1bdc4 | 140 | if (scm_gc_running_p) |
eab1b259 | 141 | return; |
c8a1bdc4 HWN |
142 | |
143 | /* | |
eab1b259 HWN |
144 | Only scm_in_heap_p and rescanning the heap is wildly |
145 | expensive. | |
146 | */ | |
147 | if (scm_expensive_debug_cell_accesses_p) | |
148 | scm_i_expensive_validation_check (cell); | |
b4246e5b | 149 | |
eab1b259 | 150 | scm_i_cell_validation_already_running = 0; /* re-enable */ |
406c7d90 DH |
151 | } |
152 | } | |
153 | ||
154 | ||
eab1b259 | 155 | |
406c7d90 DH |
156 | SCM_DEFINE (scm_set_debug_cell_accesses_x, "set-debug-cell-accesses!", 1, 0, 0, |
157 | (SCM flag), | |
1e6808ea | 158 | "If @var{flag} is @code{#f}, cell access checking is disabled.\n" |
eab1b259 | 159 | "If @var{flag} is @code{#t}, cheap cell access checking is enabled,\n" |
e81d98ec | 160 | "but no additional calls to garbage collection are issued.\n" |
eab1b259 | 161 | "If @var{flag} is a number, strict cell access checking is enabled,\n" |
e81d98ec DH |
162 | "with an additional garbage collection after the given\n" |
163 | "number of cell accesses.\n" | |
1e6808ea MG |
164 | "This procedure only exists when the compile-time flag\n" |
165 | "@code{SCM_DEBUG_CELL_ACCESSES} was set to 1.") | |
406c7d90 DH |
166 | #define FUNC_NAME s_scm_set_debug_cell_accesses_x |
167 | { | |
7888309b | 168 | if (scm_is_false (flag)) |
eab1b259 HWN |
169 | { |
170 | scm_debug_cell_accesses_p = 0; | |
171 | } | |
bc36d050 | 172 | else if (scm_is_eq (flag, SCM_BOOL_T)) |
eab1b259 HWN |
173 | { |
174 | scm_debug_cells_gc_interval = 0; | |
175 | scm_debug_cell_accesses_p = 1; | |
176 | scm_expensive_debug_cell_accesses_p = 0; | |
177 | } | |
e11e83f3 | 178 | else |
eab1b259 | 179 | { |
e11e83f3 | 180 | scm_debug_cells_gc_interval = scm_to_signed_integer (flag, 0, INT_MAX); |
eab1b259 HWN |
181 | scm_debug_cell_accesses_p = 1; |
182 | scm_expensive_debug_cell_accesses_p = 1; | |
183 | } | |
406c7d90 DH |
184 | return SCM_UNSPECIFIED; |
185 | } | |
186 | #undef FUNC_NAME | |
0f2d19dd | 187 | |
ecf470a2 | 188 | |
c8a1bdc4 | 189 | #endif /* SCM_DEBUG_CELL_ACCESSES == 1 */ |
0f2d19dd JB |
190 | |
191 | \f | |
26224b3f LC |
192 | /* Hooks. */ |
193 | scm_t_c_hook scm_before_gc_c_hook; | |
194 | scm_t_c_hook scm_before_mark_c_hook; | |
195 | scm_t_c_hook scm_before_sweep_c_hook; | |
196 | scm_t_c_hook scm_after_sweep_c_hook; | |
197 | scm_t_c_hook scm_after_gc_c_hook; | |
945fec60 | 198 | |
0f2d19dd | 199 | |
0f2d19dd JB |
200 | /* GC Statistics Keeping |
201 | */ | |
b74e86cf LC |
202 | unsigned long scm_gc_ports_collected = 0; |
203 | ||
915b3f9f | 204 | static unsigned long protected_obj_count = 0; |
c2cbcc57 | 205 | |
0f2d19dd JB |
206 | |
207 | SCM_SYMBOL (sym_cells_allocated, "cells-allocated"); | |
915b3f9f LC |
208 | SCM_SYMBOL (sym_heap_size, "heap-size"); |
209 | SCM_SYMBOL (sym_heap_free_size, "heap-free-size"); | |
210 | SCM_SYMBOL (sym_heap_total_allocated, "heap-total-allocated"); | |
0f2d19dd JB |
211 | SCM_SYMBOL (sym_mallocated, "bytes-malloced"); |
212 | SCM_SYMBOL (sym_mtrigger, "gc-malloc-threshold"); | |
213 | SCM_SYMBOL (sym_heap_segments, "cell-heap-segments"); | |
214 | SCM_SYMBOL (sym_gc_time_taken, "gc-time-taken"); | |
c9b0d4b0 | 215 | SCM_SYMBOL (sym_gc_mark_time_taken, "gc-mark-time-taken"); |
c9b0d4b0 ML |
216 | SCM_SYMBOL (sym_times, "gc-times"); |
217 | SCM_SYMBOL (sym_cells_marked, "cells-marked"); | |
40945e5e | 218 | SCM_SYMBOL (sym_cells_marked_conservatively, "cells-marked-conservatively"); |
c9b0d4b0 | 219 | SCM_SYMBOL (sym_cells_swept, "cells-swept"); |
c2cbcc57 HWN |
220 | SCM_SYMBOL (sym_malloc_yield, "malloc-yield"); |
221 | SCM_SYMBOL (sym_cell_yield, "cell-yield"); | |
7eec4c37 | 222 | SCM_SYMBOL (sym_protected_objects, "protected-objects"); |
93632e3c | 223 | SCM_SYMBOL (sym_total_cells_allocated, "total-cells-allocated"); |
cf2d30f6 | 224 | |
d3dd80ab | 225 | |
cf2d30f6 | 226 | /* Number of calls to SCM_NEWCELL since startup. */ |
c8a1bdc4 HWN |
227 | unsigned scm_newcell_count; |
228 | unsigned scm_newcell2_count; | |
b37fe1c5 | 229 | |
b37fe1c5 | 230 | |
0f2d19dd JB |
231 | /* {Scheme Interface to GC} |
232 | */ | |
1367aa5e HWN |
233 | static SCM |
234 | tag_table_to_type_alist (void *closure, SCM key, SCM val, SCM acc) | |
235 | { | |
8fecbb19 | 236 | if (scm_is_integer (key)) |
8a00ba71 | 237 | { |
3e2073bd | 238 | int c_tag = scm_to_int (key); |
8fecbb19 HWN |
239 | |
240 | char const * name = scm_i_tag_name (c_tag); | |
241 | if (name != NULL) | |
242 | { | |
243 | key = scm_from_locale_string (name); | |
244 | } | |
245 | else | |
246 | { | |
247 | char s[100]; | |
248 | sprintf (s, "tag %d", c_tag); | |
249 | key = scm_from_locale_string (s); | |
250 | } | |
8a00ba71 | 251 | } |
8fecbb19 | 252 | |
1367aa5e HWN |
253 | return scm_cons (scm_cons (key, val), acc); |
254 | } | |
255 | ||
256 | SCM_DEFINE (scm_gc_live_object_stats, "gc-live-object-stats", 0, 0, 0, | |
257 | (), | |
258 | "Return an alist of statistics of the current live objects. ") | |
259 | #define FUNC_NAME s_scm_gc_live_object_stats | |
260 | { | |
261 | SCM tab = scm_make_hash_table (scm_from_int (57)); | |
b01532af NJ |
262 | SCM alist; |
263 | ||
b01532af | 264 | alist |
1367aa5e HWN |
265 | = scm_internal_hash_fold (&tag_table_to_type_alist, NULL, SCM_EOL, tab); |
266 | ||
267 | return alist; | |
268 | } | |
269 | #undef FUNC_NAME | |
270 | ||
c2cbcc57 | 271 | extern int scm_gc_malloc_yield_percentage; |
a00c95d9 | 272 | SCM_DEFINE (scm_gc_stats, "gc-stats", 0, 0, 0, |
1bbd0b84 | 273 | (), |
1e6808ea | 274 | "Return an association list of statistics about Guile's current\n" |
c8a1bdc4 | 275 | "use of storage.\n") |
1bbd0b84 | 276 | #define FUNC_NAME s_scm_gc_stats |
0f2d19dd | 277 | { |
0f2d19dd | 278 | SCM answer; |
915b3f9f LC |
279 | size_t heap_size, free_bytes, bytes_since_gc, total_bytes; |
280 | size_t gc_times; | |
4c9419ac | 281 | |
915b3f9f LC |
282 | heap_size = GC_get_heap_size (); |
283 | free_bytes = GC_get_free_bytes (); | |
284 | bytes_since_gc = GC_get_bytes_since_gc (); | |
285 | total_bytes = GC_get_total_bytes (); | |
286 | gc_times = GC_gc_no; | |
fca43887 | 287 | |
33b320ae NJ |
288 | /* njrev: can any of these scm_cons's or scm_list_n signal a memory |
289 | error? If so we need a frame here. */ | |
b9bd8526 | 290 | answer = |
915b3f9f LC |
291 | scm_list_n (scm_cons (sym_gc_time_taken, SCM_INUM0), |
292 | #if 0 | |
b9bd8526 MV |
293 | scm_cons (sym_cells_allocated, |
294 | scm_from_ulong (local_scm_cells_allocated)), | |
b9bd8526 MV |
295 | scm_cons (sym_mallocated, |
296 | scm_from_ulong (local_scm_mallocated)), | |
297 | scm_cons (sym_mtrigger, | |
298 | scm_from_ulong (local_scm_mtrigger)), | |
b9bd8526 MV |
299 | scm_cons (sym_gc_mark_time_taken, |
300 | scm_from_ulong (local_scm_gc_mark_time_taken)), | |
301 | scm_cons (sym_cells_marked, | |
302 | scm_from_double (local_scm_gc_cells_marked)), | |
303 | scm_cons (sym_cells_swept, | |
304 | scm_from_double (local_scm_gc_cells_swept)), | |
305 | scm_cons (sym_malloc_yield, | |
1f584400 | 306 | scm_from_long (local_scm_gc_malloc_yield_percentage)), |
b9bd8526 MV |
307 | scm_cons (sym_cell_yield, |
308 | scm_from_long (local_scm_gc_cell_yield_percentage)), | |
b9bd8526 | 309 | scm_cons (sym_heap_segments, heap_segs), |
915b3f9f LC |
310 | #endif |
311 | scm_cons (sym_heap_size, scm_from_size_t (heap_size)), | |
312 | scm_cons (sym_heap_free_size, scm_from_size_t (free_bytes)), | |
313 | scm_cons (sym_heap_total_allocated, | |
314 | scm_from_size_t (total_bytes)), | |
315 | scm_cons (sym_protected_objects, | |
316 | scm_from_ulong (protected_obj_count)), | |
317 | scm_cons (sym_times, scm_from_size_t (gc_times)), | |
b9bd8526 | 318 | SCM_UNDEFINED); |
fca43887 | 319 | |
c8a1bdc4 | 320 | return answer; |
0f2d19dd | 321 | } |
c8a1bdc4 | 322 | #undef FUNC_NAME |
0f2d19dd | 323 | |
539b08a4 | 324 | |
7f9ec18a LC |
325 | SCM_DEFINE (scm_gc_dump, "gc-dump", 0, 0, 0, |
326 | (void), | |
327 | "Dump information about the garbage collector's internal data " | |
328 | "structures and memory usage to the standard output.") | |
329 | #define FUNC_NAME s_scm_gc_dump | |
330 | { | |
331 | GC_dump (); | |
332 | ||
333 | return SCM_UNSPECIFIED; | |
334 | } | |
335 | #undef FUNC_NAME | |
336 | ||
acf4331f | 337 | |
c8a1bdc4 HWN |
338 | SCM_DEFINE (scm_object_address, "object-address", 1, 0, 0, |
339 | (SCM obj), | |
340 | "Return an integer that for the lifetime of @var{obj} is uniquely\n" | |
341 | "returned by this function for @var{obj}") | |
342 | #define FUNC_NAME s_scm_object_address | |
c68296f8 | 343 | { |
b9bd8526 | 344 | return scm_from_ulong (SCM_UNPACK (obj)); |
c68296f8 | 345 | } |
c8a1bdc4 | 346 | #undef FUNC_NAME |
c68296f8 | 347 | |
1be6b49c | 348 | |
915b3f9f LC |
349 | SCM_DEFINE (scm_gc_disable, "gc-disable", 0, 0, 0, |
350 | (), | |
351 | "Disables the garbage collector. Nested calls are permitted. " | |
352 | "GC is re-enabled once @code{gc-enable} has been called the " | |
353 | "same number of times @code{gc-disable} was called.") | |
354 | #define FUNC_NAME s_scm_gc_disable | |
355 | { | |
356 | GC_disable (); | |
357 | return SCM_UNSPECIFIED; | |
358 | } | |
359 | #undef FUNC_NAME | |
360 | ||
361 | SCM_DEFINE (scm_gc_enable, "gc-enable", 0, 0, 0, | |
362 | (), | |
363 | "Enables the garbage collector.") | |
364 | #define FUNC_NAME s_scm_gc_enable | |
365 | { | |
366 | GC_enable (); | |
367 | return SCM_UNSPECIFIED; | |
368 | } | |
369 | #undef FUNC_NAME | |
370 | ||
371 | ||
c8a1bdc4 HWN |
372 | SCM_DEFINE (scm_gc, "gc", 0, 0, 0, |
373 | (), | |
374 | "Scans all of SCM objects and reclaims for further use those that are\n" | |
375 | "no longer accessible.") | |
376 | #define FUNC_NAME s_scm_gc | |
377 | { | |
b17e0ac3 | 378 | scm_i_scm_pthread_mutex_lock (&scm_i_sweep_mutex); |
b17e0ac3 | 379 | scm_i_gc ("call"); |
33b320ae NJ |
380 | /* njrev: It looks as though other places, e.g. scm_realloc, |
381 | can call scm_i_gc without acquiring the sweep mutex. Does this | |
382 | matter? Also scm_i_gc (or its descendants) touch the | |
383 | scm_sys_protects, which are protected in some cases | |
384 | (e.g. scm_permobjs above in scm_gc_stats) by a critical section, | |
385 | not by the sweep mutex. Shouldn't all the GC-relevant objects be | |
386 | protected in the same way? */ | |
b17e0ac3 MV |
387 | scm_i_pthread_mutex_unlock (&scm_i_sweep_mutex); |
388 | scm_c_hook_run (&scm_after_gc_c_hook, 0); | |
c8a1bdc4 | 389 | return SCM_UNSPECIFIED; |
9d47a1e6 | 390 | } |
c8a1bdc4 | 391 | #undef FUNC_NAME |
9d47a1e6 | 392 | |
c8a1bdc4 | 393 | void |
b17e0ac3 | 394 | scm_i_gc (const char *what) |
c8a1bdc4 | 395 | { |
26224b3f | 396 | GC_gcollect (); |
eab1b259 | 397 | } |
0f2d19dd | 398 | |
4c7016dc | 399 | |
0f2d19dd JB |
400 | \f |
401 | /* {GC Protection Helper Functions} | |
402 | */ | |
403 | ||
404 | ||
5d2b97cd DH |
405 | /* |
406 | * If within a function you need to protect one or more scheme objects from | |
407 | * garbage collection, pass them as parameters to one of the | |
408 | * scm_remember_upto_here* functions below. These functions don't do | |
409 | * anything, but since the compiler does not know that they are actually | |
410 | * no-ops, it will generate code that calls these functions with the given | |
411 | * parameters. Therefore, you can be sure that the compiler will keep those | |
412 | * scheme values alive (on the stack or in a register) up to the point where | |
413 | * scm_remember_upto_here* is called. In other words, place the call to | |
592996c9 | 414 | * scm_remember_upto_here* _behind_ the last code in your function, that |
5d2b97cd DH |
415 | * depends on the scheme object to exist. |
416 | * | |
8c494e99 DH |
417 | * Example: We want to make sure that the string object str does not get |
418 | * garbage collected during the execution of 'some_function' in the code | |
419 | * below, because otherwise the characters belonging to str would be freed and | |
5d2b97cd DH |
420 | * 'some_function' might access freed memory. To make sure that the compiler |
421 | * keeps str alive on the stack or in a register such that it is visible to | |
422 | * the conservative gc we add the call to scm_remember_upto_here_1 _after_ the | |
423 | * call to 'some_function'. Note that this would not be necessary if str was | |
424 | * used anyway after the call to 'some_function'. | |
eb01cb64 | 425 | * char *chars = scm_i_string_chars (str); |
5d2b97cd DH |
426 | * some_function (chars); |
427 | * scm_remember_upto_here_1 (str); // str will be alive up to this point. | |
428 | */ | |
429 | ||
9e1569bd KR |
430 | /* Remove any macro versions of these while defining the functions. |
431 | Functions are always included in the library, for upward binary | |
432 | compatibility and in case combinations of GCC and non-GCC are used. */ | |
433 | #undef scm_remember_upto_here_1 | |
434 | #undef scm_remember_upto_here_2 | |
435 | ||
5d2b97cd | 436 | void |
e81d98ec | 437 | scm_remember_upto_here_1 (SCM obj SCM_UNUSED) |
5d2b97cd DH |
438 | { |
439 | /* Empty. Protects a single object from garbage collection. */ | |
440 | } | |
441 | ||
442 | void | |
e81d98ec | 443 | scm_remember_upto_here_2 (SCM obj1 SCM_UNUSED, SCM obj2 SCM_UNUSED) |
5d2b97cd DH |
444 | { |
445 | /* Empty. Protects two objects from garbage collection. */ | |
446 | } | |
447 | ||
448 | void | |
e81d98ec | 449 | scm_remember_upto_here (SCM obj SCM_UNUSED, ...) |
5d2b97cd DH |
450 | { |
451 | /* Empty. Protects any number of objects from garbage collection. */ | |
452 | } | |
453 | ||
c209c88e | 454 | /* |
41b0806d GB |
455 | These crazy functions prevent garbage collection |
456 | of arguments after the first argument by | |
457 | ensuring they remain live throughout the | |
458 | function because they are used in the last | |
459 | line of the code block. | |
460 | It'd be better to have a nice compiler hint to | |
461 | aid the conservative stack-scanning GC. --03/09/00 gjb */ | |
0f2d19dd JB |
462 | SCM |
463 | scm_return_first (SCM elt, ...) | |
0f2d19dd JB |
464 | { |
465 | return elt; | |
466 | } | |
467 | ||
41b0806d GB |
468 | int |
469 | scm_return_first_int (int i, ...) | |
470 | { | |
471 | return i; | |
472 | } | |
473 | ||
0f2d19dd | 474 | |
0f2d19dd | 475 | SCM |
6e8d25a6 | 476 | scm_permanent_object (SCM obj) |
0f2d19dd | 477 | { |
8e7b3e98 | 478 | return (scm_gc_protect_object (obj)); |
0f2d19dd JB |
479 | } |
480 | ||
481 | ||
7bd4fbe2 MD |
482 | /* Protect OBJ from the garbage collector. OBJ will not be freed, even if all |
483 | other references are dropped, until the object is unprotected by calling | |
6b1b030e | 484 | scm_gc_unprotect_object (OBJ). Calls to scm_gc_protect/unprotect_object nest, |
7bd4fbe2 MD |
485 | i. e. it is possible to protect the same object several times, but it is |
486 | necessary to unprotect the object the same number of times to actually get | |
487 | the object unprotected. It is an error to unprotect an object more often | |
488 | than it has been protected before. The function scm_protect_object returns | |
489 | OBJ. | |
490 | */ | |
491 | ||
492 | /* Implementation note: For every object X, there is a counter which | |
1f584400 | 493 | scm_gc_protect_object (X) increments and scm_gc_unprotect_object (X) decrements. |
7bd4fbe2 | 494 | */ |
686765af | 495 | |
7eec4c37 HWN |
496 | |
497 | ||
ef290276 | 498 | SCM |
6b1b030e | 499 | scm_gc_protect_object (SCM obj) |
ef290276 | 500 | { |
686765af | 501 | SCM handle; |
9d47a1e6 | 502 | |
686765af | 503 | /* This critical section barrier will be replaced by a mutex. */ |
33b320ae NJ |
504 | /* njrev: Indeed; if my comment above is correct, there is the same |
505 | critsec/mutex inconsistency here. */ | |
9de87eea | 506 | SCM_CRITICAL_SECTION_START; |
9d47a1e6 | 507 | |
e11e83f3 MV |
508 | handle = scm_hashq_create_handle_x (scm_protects, obj, scm_from_int (0)); |
509 | SCM_SETCDR (handle, scm_sum (SCM_CDR (handle), scm_from_int (1))); | |
9d47a1e6 | 510 | |
7eec4c37 HWN |
511 | protected_obj_count ++; |
512 | ||
9de87eea | 513 | SCM_CRITICAL_SECTION_END; |
9d47a1e6 | 514 | |
ef290276 JB |
515 | return obj; |
516 | } | |
517 | ||
518 | ||
519 | /* Remove any protection for OBJ established by a prior call to | |
dab7f566 | 520 | scm_protect_object. This function returns OBJ. |
ef290276 | 521 | |
dab7f566 | 522 | See scm_protect_object for more information. */ |
ef290276 | 523 | SCM |
6b1b030e | 524 | scm_gc_unprotect_object (SCM obj) |
ef290276 | 525 | { |
686765af | 526 | SCM handle; |
9d47a1e6 | 527 | |
686765af | 528 | /* This critical section barrier will be replaced by a mutex. */ |
33b320ae | 529 | /* njrev: and again. */ |
9de87eea | 530 | SCM_CRITICAL_SECTION_START; |
9d47a1e6 | 531 | |
0ff7e3ff HWN |
532 | if (scm_gc_running_p) |
533 | { | |
534 | fprintf (stderr, "scm_unprotect_object called during GC.\n"); | |
535 | abort (); | |
536 | } | |
b17e0ac3 | 537 | |
686765af | 538 | handle = scm_hashq_get_handle (scm_protects, obj); |
9d47a1e6 | 539 | |
7888309b | 540 | if (scm_is_false (handle)) |
686765af | 541 | { |
0f0f0899 MD |
542 | fprintf (stderr, "scm_unprotect_object called on unprotected object\n"); |
543 | abort (); | |
686765af | 544 | } |
6a199940 DH |
545 | else |
546 | { | |
e11e83f3 | 547 | SCM count = scm_difference (SCM_CDR (handle), scm_from_int (1)); |
bc36d050 | 548 | if (scm_is_eq (count, scm_from_int (0))) |
6a199940 DH |
549 | scm_hashq_remove_x (scm_protects, obj); |
550 | else | |
1be6b49c | 551 | SCM_SETCDR (handle, count); |
6a199940 | 552 | } |
7eec4c37 | 553 | protected_obj_count --; |
686765af | 554 | |
9de87eea | 555 | SCM_CRITICAL_SECTION_END; |
ef290276 JB |
556 | |
557 | return obj; | |
558 | } | |
559 | ||
6b1b030e ML |
560 | void |
561 | scm_gc_register_root (SCM *p) | |
562 | { | |
8e7b3e98 | 563 | /* Nothing. */ |
6b1b030e ML |
564 | } |
565 | ||
566 | void | |
567 | scm_gc_unregister_root (SCM *p) | |
568 | { | |
8e7b3e98 | 569 | /* Nothing. */ |
6b1b030e ML |
570 | } |
571 | ||
572 | void | |
573 | scm_gc_register_roots (SCM *b, unsigned long n) | |
574 | { | |
575 | SCM *p = b; | |
576 | for (; p < b + n; ++p) | |
577 | scm_gc_register_root (p); | |
578 | } | |
579 | ||
580 | void | |
581 | scm_gc_unregister_roots (SCM *b, unsigned long n) | |
582 | { | |
583 | SCM *p = b; | |
584 | for (; p < b + n; ++p) | |
585 | scm_gc_unregister_root (p); | |
586 | } | |
587 | ||
04a98cff | 588 | int scm_i_terminating; |
c45acc34 | 589 | |
0f2d19dd | 590 | \f |
a00c95d9 | 591 | |
4c48ba06 | 592 | |
c8a1bdc4 HWN |
593 | /* |
594 | MOVE THIS FUNCTION. IT DOES NOT HAVE ANYTHING TODO WITH GC. | |
595 | */ | |
85db4a2c DH |
596 | |
597 | /* Get an integer from an environment variable. */ | |
c8a1bdc4 HWN |
598 | int |
599 | scm_getenv_int (const char *var, int def) | |
85db4a2c | 600 | { |
c8a1bdc4 HWN |
601 | char *end = 0; |
602 | char *val = getenv (var); | |
603 | long res = def; | |
85db4a2c DH |
604 | if (!val) |
605 | return def; | |
606 | res = strtol (val, &end, 10); | |
607 | if (end == val) | |
608 | return def; | |
609 | return res; | |
610 | } | |
611 | ||
c35738c1 MD |
612 | void |
613 | scm_storage_prehistory () | |
614 | { | |
184327a6 | 615 | GC_all_interior_pointers = 0; |
21c097e0 | 616 | GC_set_free_space_divisor (scm_getenv_int ("GC_FREE_SPACE_DIVISOR", 3)); |
184327a6 | 617 | |
a82e7953 | 618 | GC_INIT (); |
e7bca227 | 619 | |
11d2fc06 LC |
620 | #if (! ((defined GC_VERSION_MAJOR) && (GC_VERSION_MAJOR >= 7))) \ |
621 | && (defined SCM_I_GSC_USE_PTHREAD_THREADS) | |
e7bca227 LC |
622 | /* When using GC 6.8, this call is required to initialize thread-local |
623 | freelists (shouldn't be necessary with GC 7.0). */ | |
624 | GC_init (); | |
625 | #endif | |
626 | ||
fdab75a1 | 627 | GC_expand_hp (SCM_DEFAULT_INIT_HEAP_SIZE_2); |
915b3f9f | 628 | |
184327a6 LC |
629 | /* We only need to register a displacement for those types for which the |
630 | higher bits of the type tag are used to store a pointer (that is, a | |
631 | pointer to an 8-octet aligned region). For `scm_tc3_struct', this is | |
632 | handled in `scm_alloc_struct ()'. */ | |
633 | GC_REGISTER_DISPLACEMENT (scm_tc3_cons); | |
314b8716 | 634 | /* GC_REGISTER_DISPLACEMENT (scm_tc3_unused); */ |
184327a6 | 635 | |
915b3f9f LC |
636 | /* Sanity check. */ |
637 | if (!GC_is_visible (scm_sys_protects)) | |
638 | abort (); | |
a82e7953 | 639 | |
c35738c1 MD |
640 | scm_c_hook_init (&scm_before_gc_c_hook, 0, SCM_C_HOOK_NORMAL); |
641 | scm_c_hook_init (&scm_before_mark_c_hook, 0, SCM_C_HOOK_NORMAL); | |
642 | scm_c_hook_init (&scm_before_sweep_c_hook, 0, SCM_C_HOOK_NORMAL); | |
643 | scm_c_hook_init (&scm_after_sweep_c_hook, 0, SCM_C_HOOK_NORMAL); | |
644 | scm_c_hook_init (&scm_after_gc_c_hook, 0, SCM_C_HOOK_NORMAL); | |
645 | } | |
85db4a2c | 646 | |
9de87eea | 647 | scm_i_pthread_mutex_t scm_i_gc_admin_mutex = SCM_I_PTHREAD_MUTEX_INITIALIZER; |
eb01cb64 | 648 | |
4a4c9785 | 649 | int |
85db4a2c | 650 | scm_init_storage () |
0f2d19dd | 651 | { |
1be6b49c | 652 | size_t j; |
0f2d19dd JB |
653 | |
654 | j = SCM_NUM_PROTECTS; | |
655 | while (j) | |
656 | scm_sys_protects[--j] = SCM_BOOL_F; | |
4a4c9785 | 657 | |
9de87eea MV |
658 | #if 0 |
659 | /* We can't have a cleanup handler since we have no thread to run it | |
660 | in. */ | |
661 | ||
a18bcd0e | 662 | #ifdef HAVE_ATEXIT |
c45acc34 | 663 | atexit (cleanup); |
e52ceaac MD |
664 | #else |
665 | #ifdef HAVE_ON_EXIT | |
666 | on_exit (cleanup, 0); | |
667 | #endif | |
9de87eea MV |
668 | #endif |
669 | ||
a18bcd0e | 670 | #endif |
0f2d19dd | 671 | |
00ffa0e7 | 672 | scm_protects = scm_c_make_hash_table (31); |
d6884e63 | 673 | |
0f2d19dd JB |
674 | return 0; |
675 | } | |
939794ce | 676 | |
0f2d19dd JB |
677 | \f |
678 | ||
939794ce DH |
679 | SCM scm_after_gc_hook; |
680 | ||
939794ce DH |
681 | static SCM gc_async; |
682 | ||
939794ce DH |
683 | /* The function gc_async_thunk causes the execution of the after-gc-hook. It |
684 | * is run after the gc, as soon as the asynchronous events are handled by the | |
685 | * evaluator. | |
686 | */ | |
687 | static SCM | |
688 | gc_async_thunk (void) | |
689 | { | |
690 | scm_c_run_hook (scm_after_gc_hook, SCM_EOL); | |
939794ce DH |
691 | return SCM_UNSPECIFIED; |
692 | } | |
693 | ||
694 | ||
695 | /* The function mark_gc_async is run by the scm_after_gc_c_hook at the end of | |
696 | * the garbage collection. The only purpose of this function is to mark the | |
697 | * gc_async (which will eventually lead to the execution of the | |
698 | * gc_async_thunk). | |
699 | */ | |
700 | static void * | |
e81d98ec | 701 | mark_gc_async (void * hook_data SCM_UNUSED, |
5c004b6d | 702 | void *fn_data SCM_UNUSED, |
e81d98ec DH |
703 | void *data SCM_UNUSED) |
704 | { | |
705 | /* If cell access debugging is enabled, the user may choose to perform | |
706 | * additional garbage collections after an arbitrary number of cell | |
707 | * accesses. We don't want the scheme level after-gc-hook to be performed | |
708 | * for each of these garbage collections for the following reason: The | |
709 | * execution of the after-gc-hook causes cell accesses itself. Thus, if the | |
710 | * after-gc-hook was performed with every gc, and if the gc was performed | |
711 | * after a very small number of cell accesses, then the number of cell | |
712 | * accesses during the execution of the after-gc-hook will suffice to cause | |
713 | * the execution of the next gc. Then, guile would keep executing the | |
714 | * after-gc-hook over and over again, and would never come to do other | |
715 | * things. | |
eae33935 | 716 | * |
e81d98ec DH |
717 | * To overcome this problem, if cell access debugging with additional |
718 | * garbage collections is enabled, the after-gc-hook is never run by the | |
719 | * garbage collecter. When running guile with cell access debugging and the | |
720 | * execution of the after-gc-hook is desired, then it is necessary to run | |
721 | * the hook explicitly from the user code. This has the effect, that from | |
722 | * the scheme level point of view it seems that garbage collection is | |
723 | * performed with a much lower frequency than it actually is. Obviously, | |
724 | * this will not work for code that depends on a fixed one to one | |
725 | * relationship between the execution counts of the C level garbage | |
726 | * collection hooks and the execution count of the scheme level | |
727 | * after-gc-hook. | |
728 | */ | |
9de87eea | 729 | |
e81d98ec | 730 | #if (SCM_DEBUG_CELL_ACCESSES == 1) |
eab1b259 | 731 | if (scm_debug_cells_gc_interval == 0) |
e81d98ec DH |
732 | scm_system_async_mark (gc_async); |
733 | #else | |
939794ce | 734 | scm_system_async_mark (gc_async); |
e81d98ec DH |
735 | #endif |
736 | ||
939794ce DH |
737 | return NULL; |
738 | } | |
739 | ||
26224b3f LC |
740 | char const * |
741 | scm_i_tag_name (scm_t_bits tag) | |
742 | { | |
743 | if (tag >= 255) | |
744 | { | |
f86f3b5b LC |
745 | int k = 0xff & (tag >> 8); |
746 | return (scm_smobs[k].name); | |
26224b3f | 747 | } |
f86f3b5b | 748 | |
26224b3f LC |
749 | switch (tag) /* 7 bits */ |
750 | { | |
751 | case scm_tcs_struct: | |
752 | return "struct"; | |
753 | case scm_tcs_cons_imcar: | |
754 | return "cons (immediate car)"; | |
755 | case scm_tcs_cons_nimcar: | |
756 | return "cons (non-immediate car)"; | |
26224b3f LC |
757 | case scm_tc7_pws: |
758 | return "pws"; | |
c99de5aa AW |
759 | case scm_tc7_hashtable: |
760 | return "hashtable"; | |
9ea31741 AW |
761 | case scm_tc7_fluid: |
762 | return "fluid"; | |
763 | case scm_tc7_dynamic_state: | |
764 | return "dynamic state"; | |
26224b3f LC |
765 | case scm_tc7_wvect: |
766 | return "weak vector"; | |
767 | case scm_tc7_vector: | |
768 | return "vector"; | |
26224b3f LC |
769 | case scm_tc7_number: |
770 | switch (tag) | |
771 | { | |
772 | case scm_tc16_real: | |
773 | return "real"; | |
774 | break; | |
775 | case scm_tc16_big: | |
776 | return "bignum"; | |
777 | break; | |
778 | case scm_tc16_complex: | |
779 | return "complex number"; | |
780 | break; | |
781 | case scm_tc16_fraction: | |
782 | return "fraction"; | |
783 | break; | |
784 | } | |
785 | break; | |
786 | case scm_tc7_string: | |
787 | return "string"; | |
788 | break; | |
789 | case scm_tc7_stringbuf: | |
790 | return "string buffer"; | |
791 | break; | |
792 | case scm_tc7_symbol: | |
793 | return "symbol"; | |
794 | break; | |
795 | case scm_tc7_variable: | |
796 | return "variable"; | |
797 | break; | |
f36878ba AW |
798 | case scm_tc7_gsubr: |
799 | return "gsubr"; | |
26224b3f LC |
800 | break; |
801 | case scm_tc7_port: | |
802 | return "port"; | |
803 | break; | |
804 | case scm_tc7_smob: | |
805 | return "smob"; /* should not occur. */ | |
806 | break; | |
807 | } | |
808 | ||
809 | return NULL; | |
810 | } | |
811 | ||
812 | ||
26224b3f LC |
813 | |
814 | \f | |
0f2d19dd JB |
815 | void |
816 | scm_init_gc () | |
0f2d19dd | 817 | { |
a82e7953 | 818 | /* `GC_INIT ()' was invoked in `scm_storage_prehistory ()'. */ |
d678e25c | 819 | |
fde50407 ML |
820 | scm_after_gc_hook = scm_permanent_object (scm_make_hook (SCM_INUM0)); |
821 | scm_c_define ("after-gc-hook", scm_after_gc_hook); | |
939794ce | 822 | |
df9ca8d8 | 823 | gc_async = scm_c_make_gsubr ("%gc-thunk", 0, 0, 0, gc_async_thunk); |
939794ce DH |
824 | |
825 | scm_c_hook_add (&scm_after_gc_c_hook, mark_gc_async, NULL, 0); | |
826 | ||
a0599745 | 827 | #include "libguile/gc.x" |
0f2d19dd | 828 | } |
89e00824 | 829 | |
c8a1bdc4 HWN |
830 | |
831 | void | |
832 | scm_gc_sweep (void) | |
833 | #define FUNC_NAME "scm_gc_sweep" | |
834 | { | |
26224b3f LC |
835 | /* FIXME */ |
836 | fprintf (stderr, "%s: doing nothing\n", __FUNCTION__); | |
c8a1bdc4 HWN |
837 | } |
838 | ||
839 | #undef FUNC_NAME | |
840 | ||
841 | ||
56495472 | 842 | |
89e00824 ML |
843 | /* |
844 | Local Variables: | |
845 | c-file-style: "gnu" | |
846 | End: | |
847 | */ |