* lisp.h: Include <intprops.h>, as it'll useful in later changes.
[bpt/emacs.git] / src / alloc.c
1 /* Storage allocation and gc for GNU Emacs Lisp interpreter.
2 Copyright (C) 1985-1986, 1988, 1993-1995, 1997-2011
3 Free Software Foundation, Inc.
4
5 This file is part of GNU Emacs.
6
7 GNU Emacs is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
11
12 GNU Emacs is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */
19
20 #include <config.h>
21 #include <stdio.h>
22 #include <limits.h> /* For CHAR_BIT. */
23 #include <setjmp.h>
24
25 #include <signal.h>
26
27 #ifdef HAVE_GTK_AND_PTHREAD
28 #include <pthread.h>
29 #endif
30
31 /* This file is part of the core Lisp implementation, and thus must
32 deal with the real data structures. If the Lisp implementation is
33 replaced, this file likely will not be used. */
34
35 #undef HIDE_LISP_IMPLEMENTATION
36 #include "lisp.h"
37 #include "process.h"
38 #include "intervals.h"
39 #include "puresize.h"
40 #include "buffer.h"
41 #include "window.h"
42 #include "keyboard.h"
43 #include "frame.h"
44 #include "blockinput.h"
45 #include "character.h"
46 #include "syssignal.h"
47 #include "termhooks.h" /* For struct terminal. */
48 #include <setjmp.h>
49
50 /* GC_MALLOC_CHECK defined means perform validity checks of malloc'd
51 memory. Can do this only if using gmalloc.c. */
52
53 #if defined SYSTEM_MALLOC || defined DOUG_LEA_MALLOC
54 #undef GC_MALLOC_CHECK
55 #endif
56
57 #include <unistd.h>
58 #ifndef HAVE_UNISTD_H
59 extern POINTER_TYPE *sbrk ();
60 #endif
61
62 #include <fcntl.h>
63
64 #ifdef WINDOWSNT
65 #include "w32.h"
66 #endif
67
68 #ifdef DOUG_LEA_MALLOC
69
70 #include <malloc.h>
71 /* malloc.h #defines this as size_t, at least in glibc2. */
72 #ifndef __malloc_size_t
73 #define __malloc_size_t int
74 #endif
75
76 /* Specify maximum number of areas to mmap. It would be nice to use a
77 value that explicitly means "no limit". */
78
79 #define MMAP_MAX_AREAS 100000000
80
81 #else /* not DOUG_LEA_MALLOC */
82
83 /* The following come from gmalloc.c. */
84
85 #define __malloc_size_t size_t
86 extern __malloc_size_t _bytes_used;
87 extern __malloc_size_t __malloc_extra_blocks;
88
89 #endif /* not DOUG_LEA_MALLOC */
90
91 #if ! defined SYSTEM_MALLOC && ! defined SYNC_INPUT
92 #ifdef HAVE_GTK_AND_PTHREAD
93
94 /* When GTK uses the file chooser dialog, different backends can be loaded
95 dynamically. One such a backend is the Gnome VFS backend that gets loaded
96 if you run Gnome. That backend creates several threads and also allocates
97 memory with malloc.
98
99 If Emacs sets malloc hooks (! SYSTEM_MALLOC) and the emacs_blocked_*
100 functions below are called from malloc, there is a chance that one
101 of these threads preempts the Emacs main thread and the hook variables
102 end up in an inconsistent state. So we have a mutex to prevent that (note
103 that the backend handles concurrent access to malloc within its own threads
104 but Emacs code running in the main thread is not included in that control).
105
106 When UNBLOCK_INPUT is called, reinvoke_input_signal may be called. If this
107 happens in one of the backend threads we will have two threads that tries
108 to run Emacs code at once, and the code is not prepared for that.
109 To prevent that, we only call BLOCK/UNBLOCK from the main thread. */
110
111 static pthread_mutex_t alloc_mutex;
112
113 #define BLOCK_INPUT_ALLOC \
114 do \
115 { \
116 if (pthread_equal (pthread_self (), main_thread)) \
117 BLOCK_INPUT; \
118 pthread_mutex_lock (&alloc_mutex); \
119 } \
120 while (0)
121 #define UNBLOCK_INPUT_ALLOC \
122 do \
123 { \
124 pthread_mutex_unlock (&alloc_mutex); \
125 if (pthread_equal (pthread_self (), main_thread)) \
126 UNBLOCK_INPUT; \
127 } \
128 while (0)
129
130 #else /* ! defined HAVE_GTK_AND_PTHREAD */
131
132 #define BLOCK_INPUT_ALLOC BLOCK_INPUT
133 #define UNBLOCK_INPUT_ALLOC UNBLOCK_INPUT
134
135 #endif /* ! defined HAVE_GTK_AND_PTHREAD */
136 #endif /* ! defined SYSTEM_MALLOC && ! defined SYNC_INPUT */
137
138 /* Mark, unmark, query mark bit of a Lisp string. S must be a pointer
139 to a struct Lisp_String. */
140
141 #define MARK_STRING(S) ((S)->size |= ARRAY_MARK_FLAG)
142 #define UNMARK_STRING(S) ((S)->size &= ~ARRAY_MARK_FLAG)
143 #define STRING_MARKED_P(S) (((S)->size & ARRAY_MARK_FLAG) != 0)
144
145 #define VECTOR_MARK(V) ((V)->header.size |= ARRAY_MARK_FLAG)
146 #define VECTOR_UNMARK(V) ((V)->header.size &= ~ARRAY_MARK_FLAG)
147 #define VECTOR_MARKED_P(V) (((V)->header.size & ARRAY_MARK_FLAG) != 0)
148
149 /* Value is the number of bytes of S, a pointer to a struct Lisp_String.
150 Be careful during GC, because S->size contains the mark bit for
151 strings. */
152
153 #define GC_STRING_BYTES(S) (STRING_BYTES (S))
154
155 /* Global variables. */
156 struct emacs_globals globals;
157
158 /* Number of bytes of consing done since the last gc. */
159
160 EMACS_INT consing_since_gc;
161
162 /* Similar minimum, computed from Vgc_cons_percentage. */
163
164 EMACS_INT gc_relative_threshold;
165
166 /* Minimum number of bytes of consing since GC before next GC,
167 when memory is full. */
168
169 EMACS_INT memory_full_cons_threshold;
170
171 /* Nonzero during GC. */
172
173 int gc_in_progress;
174
175 /* Nonzero means abort if try to GC.
176 This is for code which is written on the assumption that
177 no GC will happen, so as to verify that assumption. */
178
179 int abort_on_gc;
180
181 /* Number of live and free conses etc. */
182
183 static int total_conses, total_markers, total_symbols, total_vector_size;
184 static int total_free_conses, total_free_markers, total_free_symbols;
185 static int total_free_floats, total_floats;
186
187 /* Points to memory space allocated as "spare", to be freed if we run
188 out of memory. We keep one large block, four cons-blocks, and
189 two string blocks. */
190
191 static char *spare_memory[7];
192
193 #ifndef SYSTEM_MALLOC
194 /* Amount of spare memory to keep in large reserve block. */
195
196 #define SPARE_MEMORY (1 << 14)
197 #endif
198
199 /* Number of extra blocks malloc should get when it needs more core. */
200
201 static int malloc_hysteresis;
202
203 /* Initialize it to a nonzero value to force it into data space
204 (rather than bss space). That way unexec will remap it into text
205 space (pure), on some systems. We have not implemented the
206 remapping on more recent systems because this is less important
207 nowadays than in the days of small memories and timesharing. */
208
209 #ifndef VIRT_ADDR_VARIES
210 static
211 #endif
212 EMACS_INT pure[(PURESIZE + sizeof (EMACS_INT) - 1) / sizeof (EMACS_INT)] = {1,};
213 #define PUREBEG (char *) pure
214
215 /* Pointer to the pure area, and its size. */
216
217 static char *purebeg;
218 static size_t pure_size;
219
220 /* Number of bytes of pure storage used before pure storage overflowed.
221 If this is non-zero, this implies that an overflow occurred. */
222
223 static size_t pure_bytes_used_before_overflow;
224
225 /* Value is non-zero if P points into pure space. */
226
227 #define PURE_POINTER_P(P) \
228 (((PNTR_COMPARISON_TYPE) (P) \
229 < (PNTR_COMPARISON_TYPE) ((char *) purebeg + pure_size)) \
230 && ((PNTR_COMPARISON_TYPE) (P) \
231 >= (PNTR_COMPARISON_TYPE) purebeg))
232
233 /* Index in pure at which next pure Lisp object will be allocated.. */
234
235 static EMACS_INT pure_bytes_used_lisp;
236
237 /* Number of bytes allocated for non-Lisp objects in pure storage. */
238
239 static EMACS_INT pure_bytes_used_non_lisp;
240
241 /* If nonzero, this is a warning delivered by malloc and not yet
242 displayed. */
243
244 const char *pending_malloc_warning;
245
246 /* Maximum amount of C stack to save when a GC happens. */
247
248 #ifndef MAX_SAVE_STACK
249 #define MAX_SAVE_STACK 16000
250 #endif
251
252 /* Buffer in which we save a copy of the C stack at each GC. */
253
254 #if MAX_SAVE_STACK > 0
255 static char *stack_copy;
256 static size_t stack_copy_size;
257 #endif
258
259 /* Non-zero means ignore malloc warnings. Set during initialization.
260 Currently not used. */
261
262 static int ignore_warnings;
263
264 static Lisp_Object Qgc_cons_threshold;
265 Lisp_Object Qchar_table_extra_slots;
266
267 /* Hook run after GC has finished. */
268
269 static Lisp_Object Qpost_gc_hook;
270
271 static void mark_buffer (Lisp_Object);
272 static void mark_terminals (void);
273 static void gc_sweep (void);
274 static void mark_glyph_matrix (struct glyph_matrix *);
275 static void mark_face_cache (struct face_cache *);
276
277 #if !defined REL_ALLOC || defined SYSTEM_MALLOC
278 static void refill_memory_reserve (void);
279 #endif
280 static struct Lisp_String *allocate_string (void);
281 static void compact_small_strings (void);
282 static void free_large_strings (void);
283 static void sweep_strings (void);
284 static void free_misc (Lisp_Object);
285
286 /* When scanning the C stack for live Lisp objects, Emacs keeps track
287 of what memory allocated via lisp_malloc is intended for what
288 purpose. This enumeration specifies the type of memory. */
289
290 enum mem_type
291 {
292 MEM_TYPE_NON_LISP,
293 MEM_TYPE_BUFFER,
294 MEM_TYPE_CONS,
295 MEM_TYPE_STRING,
296 MEM_TYPE_MISC,
297 MEM_TYPE_SYMBOL,
298 MEM_TYPE_FLOAT,
299 /* We used to keep separate mem_types for subtypes of vectors such as
300 process, hash_table, frame, terminal, and window, but we never made
301 use of the distinction, so it only caused source-code complexity
302 and runtime slowdown. Minor but pointless. */
303 MEM_TYPE_VECTORLIKE
304 };
305
306 static POINTER_TYPE *lisp_align_malloc (size_t, enum mem_type);
307 static POINTER_TYPE *lisp_malloc (size_t, enum mem_type);
308
309
310 #if GC_MARK_STACK || defined GC_MALLOC_CHECK
311
312 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
313 #include <stdio.h> /* For fprintf. */
314 #endif
315
316 /* A unique object in pure space used to make some Lisp objects
317 on free lists recognizable in O(1). */
318
319 static Lisp_Object Vdead;
320
321 #ifdef GC_MALLOC_CHECK
322
323 enum mem_type allocated_mem_type;
324 static int dont_register_blocks;
325
326 #endif /* GC_MALLOC_CHECK */
327
328 /* A node in the red-black tree describing allocated memory containing
329 Lisp data. Each such block is recorded with its start and end
330 address when it is allocated, and removed from the tree when it
331 is freed.
332
333 A red-black tree is a balanced binary tree with the following
334 properties:
335
336 1. Every node is either red or black.
337 2. Every leaf is black.
338 3. If a node is red, then both of its children are black.
339 4. Every simple path from a node to a descendant leaf contains
340 the same number of black nodes.
341 5. The root is always black.
342
343 When nodes are inserted into the tree, or deleted from the tree,
344 the tree is "fixed" so that these properties are always true.
345
346 A red-black tree with N internal nodes has height at most 2
347 log(N+1). Searches, insertions and deletions are done in O(log N).
348 Please see a text book about data structures for a detailed
349 description of red-black trees. Any book worth its salt should
350 describe them. */
351
352 struct mem_node
353 {
354 /* Children of this node. These pointers are never NULL. When there
355 is no child, the value is MEM_NIL, which points to a dummy node. */
356 struct mem_node *left, *right;
357
358 /* The parent of this node. In the root node, this is NULL. */
359 struct mem_node *parent;
360
361 /* Start and end of allocated region. */
362 void *start, *end;
363
364 /* Node color. */
365 enum {MEM_BLACK, MEM_RED} color;
366
367 /* Memory type. */
368 enum mem_type type;
369 };
370
371 /* Base address of stack. Set in main. */
372
373 Lisp_Object *stack_base;
374
375 /* Root of the tree describing allocated Lisp memory. */
376
377 static struct mem_node *mem_root;
378
379 /* Lowest and highest known address in the heap. */
380
381 static void *min_heap_address, *max_heap_address;
382
383 /* Sentinel node of the tree. */
384
385 static struct mem_node mem_z;
386 #define MEM_NIL &mem_z
387
388 static struct Lisp_Vector *allocate_vectorlike (EMACS_INT);
389 static void lisp_free (POINTER_TYPE *);
390 static void mark_stack (void);
391 static int live_vector_p (struct mem_node *, void *);
392 static int live_buffer_p (struct mem_node *, void *);
393 static int live_string_p (struct mem_node *, void *);
394 static int live_cons_p (struct mem_node *, void *);
395 static int live_symbol_p (struct mem_node *, void *);
396 static int live_float_p (struct mem_node *, void *);
397 static int live_misc_p (struct mem_node *, void *);
398 static void mark_maybe_object (Lisp_Object);
399 static void mark_memory (void *, void *, int);
400 static void mem_init (void);
401 static struct mem_node *mem_insert (void *, void *, enum mem_type);
402 static void mem_insert_fixup (struct mem_node *);
403 static void mem_rotate_left (struct mem_node *);
404 static void mem_rotate_right (struct mem_node *);
405 static void mem_delete (struct mem_node *);
406 static void mem_delete_fixup (struct mem_node *);
407 static inline struct mem_node *mem_find (void *);
408
409
410 #if GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS
411 static void check_gcpros (void);
412 #endif
413
414 #endif /* GC_MARK_STACK || GC_MALLOC_CHECK */
415
416 /* Recording what needs to be marked for gc. */
417
418 struct gcpro *gcprolist;
419
420 /* Addresses of staticpro'd variables. Initialize it to a nonzero
421 value; otherwise some compilers put it into BSS. */
422
423 #define NSTATICS 0x640
424 static Lisp_Object *staticvec[NSTATICS] = {&Vpurify_flag};
425
426 /* Index of next unused slot in staticvec. */
427
428 static int staticidx = 0;
429
430 static POINTER_TYPE *pure_alloc (size_t, int);
431
432
433 /* Value is SZ rounded up to the next multiple of ALIGNMENT.
434 ALIGNMENT must be a power of 2. */
435
436 #define ALIGN(ptr, ALIGNMENT) \
437 ((POINTER_TYPE *) ((((uintptr_t) (ptr)) + (ALIGNMENT) - 1) \
438 & ~((ALIGNMENT) - 1)))
439
440
441 \f
442 /************************************************************************
443 Malloc
444 ************************************************************************/
445
446 /* Function malloc calls this if it finds we are near exhausting storage. */
447
448 void
449 malloc_warning (const char *str)
450 {
451 pending_malloc_warning = str;
452 }
453
454
455 /* Display an already-pending malloc warning. */
456
457 void
458 display_malloc_warning (void)
459 {
460 call3 (intern ("display-warning"),
461 intern ("alloc"),
462 build_string (pending_malloc_warning),
463 intern ("emergency"));
464 pending_malloc_warning = 0;
465 }
466 \f
467 /* Called if we can't allocate relocatable space for a buffer. */
468
469 void
470 buffer_memory_full (EMACS_INT nbytes)
471 {
472 /* If buffers use the relocating allocator, no need to free
473 spare_memory, because we may have plenty of malloc space left
474 that we could get, and if we don't, the malloc that fails will
475 itself cause spare_memory to be freed. If buffers don't use the
476 relocating allocator, treat this like any other failing
477 malloc. */
478
479 #ifndef REL_ALLOC
480 memory_full (nbytes);
481 #endif
482
483 /* This used to call error, but if we've run out of memory, we could
484 get infinite recursion trying to build the string. */
485 xsignal (Qnil, Vmemory_signal_data);
486 }
487
488
489 #ifdef XMALLOC_OVERRUN_CHECK
490
491 /* Check for overrun in malloc'ed buffers by wrapping a 16 byte header
492 and a 16 byte trailer around each block.
493
494 The header consists of 12 fixed bytes + a 4 byte integer contaning the
495 original block size, while the trailer consists of 16 fixed bytes.
496
497 The header is used to detect whether this block has been allocated
498 through these functions -- as it seems that some low-level libc
499 functions may bypass the malloc hooks.
500 */
501
502
503 #define XMALLOC_OVERRUN_CHECK_SIZE 16
504
505 static char xmalloc_overrun_check_header[XMALLOC_OVERRUN_CHECK_SIZE-4] =
506 { 0x9a, 0x9b, 0xae, 0xaf,
507 0xbf, 0xbe, 0xce, 0xcf,
508 0xea, 0xeb, 0xec, 0xed };
509
510 static char xmalloc_overrun_check_trailer[XMALLOC_OVERRUN_CHECK_SIZE] =
511 { 0xaa, 0xab, 0xac, 0xad,
512 0xba, 0xbb, 0xbc, 0xbd,
513 0xca, 0xcb, 0xcc, 0xcd,
514 0xda, 0xdb, 0xdc, 0xdd };
515
516 /* Macros to insert and extract the block size in the header. */
517
518 #define XMALLOC_PUT_SIZE(ptr, size) \
519 (ptr[-1] = (size & 0xff), \
520 ptr[-2] = ((size >> 8) & 0xff), \
521 ptr[-3] = ((size >> 16) & 0xff), \
522 ptr[-4] = ((size >> 24) & 0xff))
523
524 #define XMALLOC_GET_SIZE(ptr) \
525 (size_t)((unsigned)(ptr[-1]) | \
526 ((unsigned)(ptr[-2]) << 8) | \
527 ((unsigned)(ptr[-3]) << 16) | \
528 ((unsigned)(ptr[-4]) << 24))
529
530
531 /* The call depth in overrun_check functions. For example, this might happen:
532 xmalloc()
533 overrun_check_malloc()
534 -> malloc -> (via hook)_-> emacs_blocked_malloc
535 -> overrun_check_malloc
536 call malloc (hooks are NULL, so real malloc is called).
537 malloc returns 10000.
538 add overhead, return 10016.
539 <- (back in overrun_check_malloc)
540 add overhead again, return 10032
541 xmalloc returns 10032.
542
543 (time passes).
544
545 xfree(10032)
546 overrun_check_free(10032)
547 decrease overhed
548 free(10016) <- crash, because 10000 is the original pointer. */
549
550 static int check_depth;
551
552 /* Like malloc, but wraps allocated block with header and trailer. */
553
554 static POINTER_TYPE *
555 overrun_check_malloc (size_t size)
556 {
557 register unsigned char *val;
558 size_t overhead = ++check_depth == 1 ? XMALLOC_OVERRUN_CHECK_SIZE*2 : 0;
559
560 val = (unsigned char *) malloc (size + overhead);
561 if (val && check_depth == 1)
562 {
563 memcpy (val, xmalloc_overrun_check_header,
564 XMALLOC_OVERRUN_CHECK_SIZE - 4);
565 val += XMALLOC_OVERRUN_CHECK_SIZE;
566 XMALLOC_PUT_SIZE(val, size);
567 memcpy (val + size, xmalloc_overrun_check_trailer,
568 XMALLOC_OVERRUN_CHECK_SIZE);
569 }
570 --check_depth;
571 return (POINTER_TYPE *)val;
572 }
573
574
575 /* Like realloc, but checks old block for overrun, and wraps new block
576 with header and trailer. */
577
578 static POINTER_TYPE *
579 overrun_check_realloc (POINTER_TYPE *block, size_t size)
580 {
581 register unsigned char *val = (unsigned char *) block;
582 size_t overhead = ++check_depth == 1 ? XMALLOC_OVERRUN_CHECK_SIZE*2 : 0;
583
584 if (val
585 && check_depth == 1
586 && memcmp (xmalloc_overrun_check_header,
587 val - XMALLOC_OVERRUN_CHECK_SIZE,
588 XMALLOC_OVERRUN_CHECK_SIZE - 4) == 0)
589 {
590 size_t osize = XMALLOC_GET_SIZE (val);
591 if (memcmp (xmalloc_overrun_check_trailer, val + osize,
592 XMALLOC_OVERRUN_CHECK_SIZE))
593 abort ();
594 memset (val + osize, 0, XMALLOC_OVERRUN_CHECK_SIZE);
595 val -= XMALLOC_OVERRUN_CHECK_SIZE;
596 memset (val, 0, XMALLOC_OVERRUN_CHECK_SIZE);
597 }
598
599 val = (unsigned char *) realloc ((POINTER_TYPE *)val, size + overhead);
600
601 if (val && check_depth == 1)
602 {
603 memcpy (val, xmalloc_overrun_check_header,
604 XMALLOC_OVERRUN_CHECK_SIZE - 4);
605 val += XMALLOC_OVERRUN_CHECK_SIZE;
606 XMALLOC_PUT_SIZE(val, size);
607 memcpy (val + size, xmalloc_overrun_check_trailer,
608 XMALLOC_OVERRUN_CHECK_SIZE);
609 }
610 --check_depth;
611 return (POINTER_TYPE *)val;
612 }
613
614 /* Like free, but checks block for overrun. */
615
616 static void
617 overrun_check_free (POINTER_TYPE *block)
618 {
619 unsigned char *val = (unsigned char *) block;
620
621 ++check_depth;
622 if (val
623 && check_depth == 1
624 && memcmp (xmalloc_overrun_check_header,
625 val - XMALLOC_OVERRUN_CHECK_SIZE,
626 XMALLOC_OVERRUN_CHECK_SIZE - 4) == 0)
627 {
628 size_t osize = XMALLOC_GET_SIZE (val);
629 if (memcmp (xmalloc_overrun_check_trailer, val + osize,
630 XMALLOC_OVERRUN_CHECK_SIZE))
631 abort ();
632 #ifdef XMALLOC_CLEAR_FREE_MEMORY
633 val -= XMALLOC_OVERRUN_CHECK_SIZE;
634 memset (val, 0xff, osize + XMALLOC_OVERRUN_CHECK_SIZE*2);
635 #else
636 memset (val + osize, 0, XMALLOC_OVERRUN_CHECK_SIZE);
637 val -= XMALLOC_OVERRUN_CHECK_SIZE;
638 memset (val, 0, XMALLOC_OVERRUN_CHECK_SIZE);
639 #endif
640 }
641
642 free (val);
643 --check_depth;
644 }
645
646 #undef malloc
647 #undef realloc
648 #undef free
649 #define malloc overrun_check_malloc
650 #define realloc overrun_check_realloc
651 #define free overrun_check_free
652 #endif
653
654 #ifdef SYNC_INPUT
655 /* When using SYNC_INPUT, we don't call malloc from a signal handler, so
656 there's no need to block input around malloc. */
657 #define MALLOC_BLOCK_INPUT ((void)0)
658 #define MALLOC_UNBLOCK_INPUT ((void)0)
659 #else
660 #define MALLOC_BLOCK_INPUT BLOCK_INPUT
661 #define MALLOC_UNBLOCK_INPUT UNBLOCK_INPUT
662 #endif
663
664 /* Like malloc but check for no memory and block interrupt input.. */
665
666 POINTER_TYPE *
667 xmalloc (size_t size)
668 {
669 register POINTER_TYPE *val;
670
671 MALLOC_BLOCK_INPUT;
672 val = (POINTER_TYPE *) malloc (size);
673 MALLOC_UNBLOCK_INPUT;
674
675 if (!val && size)
676 memory_full (size);
677 return val;
678 }
679
680
681 /* Like realloc but check for no memory and block interrupt input.. */
682
683 POINTER_TYPE *
684 xrealloc (POINTER_TYPE *block, size_t size)
685 {
686 register POINTER_TYPE *val;
687
688 MALLOC_BLOCK_INPUT;
689 /* We must call malloc explicitly when BLOCK is 0, since some
690 reallocs don't do this. */
691 if (! block)
692 val = (POINTER_TYPE *) malloc (size);
693 else
694 val = (POINTER_TYPE *) realloc (block, size);
695 MALLOC_UNBLOCK_INPUT;
696
697 if (!val && size)
698 memory_full (size);
699 return val;
700 }
701
702
703 /* Like free but block interrupt input. */
704
705 void
706 xfree (POINTER_TYPE *block)
707 {
708 if (!block)
709 return;
710 MALLOC_BLOCK_INPUT;
711 free (block);
712 MALLOC_UNBLOCK_INPUT;
713 /* We don't call refill_memory_reserve here
714 because that duplicates doing so in emacs_blocked_free
715 and the criterion should go there. */
716 }
717
718
719 /* Like strdup, but uses xmalloc. */
720
721 char *
722 xstrdup (const char *s)
723 {
724 size_t len = strlen (s) + 1;
725 char *p = (char *) xmalloc (len);
726 memcpy (p, s, len);
727 return p;
728 }
729
730
731 /* Unwind for SAFE_ALLOCA */
732
733 Lisp_Object
734 safe_alloca_unwind (Lisp_Object arg)
735 {
736 register struct Lisp_Save_Value *p = XSAVE_VALUE (arg);
737
738 p->dogc = 0;
739 xfree (p->pointer);
740 p->pointer = 0;
741 free_misc (arg);
742 return Qnil;
743 }
744
745
746 /* Like malloc but used for allocating Lisp data. NBYTES is the
747 number of bytes to allocate, TYPE describes the intended use of the
748 allcated memory block (for strings, for conses, ...). */
749
750 #ifndef USE_LSB_TAG
751 static void *lisp_malloc_loser;
752 #endif
753
754 static POINTER_TYPE *
755 lisp_malloc (size_t nbytes, enum mem_type type)
756 {
757 register void *val;
758
759 MALLOC_BLOCK_INPUT;
760
761 #ifdef GC_MALLOC_CHECK
762 allocated_mem_type = type;
763 #endif
764
765 val = (void *) malloc (nbytes);
766
767 #ifndef USE_LSB_TAG
768 /* If the memory just allocated cannot be addressed thru a Lisp
769 object's pointer, and it needs to be,
770 that's equivalent to running out of memory. */
771 if (val && type != MEM_TYPE_NON_LISP)
772 {
773 Lisp_Object tem;
774 XSETCONS (tem, (char *) val + nbytes - 1);
775 if ((char *) XCONS (tem) != (char *) val + nbytes - 1)
776 {
777 lisp_malloc_loser = val;
778 free (val);
779 val = 0;
780 }
781 }
782 #endif
783
784 #if GC_MARK_STACK && !defined GC_MALLOC_CHECK
785 if (val && type != MEM_TYPE_NON_LISP)
786 mem_insert (val, (char *) val + nbytes, type);
787 #endif
788
789 MALLOC_UNBLOCK_INPUT;
790 if (!val && nbytes)
791 memory_full (nbytes);
792 return val;
793 }
794
795 /* Free BLOCK. This must be called to free memory allocated with a
796 call to lisp_malloc. */
797
798 static void
799 lisp_free (POINTER_TYPE *block)
800 {
801 MALLOC_BLOCK_INPUT;
802 free (block);
803 #if GC_MARK_STACK && !defined GC_MALLOC_CHECK
804 mem_delete (mem_find (block));
805 #endif
806 MALLOC_UNBLOCK_INPUT;
807 }
808
809 /* Allocation of aligned blocks of memory to store Lisp data. */
810 /* The entry point is lisp_align_malloc which returns blocks of at most */
811 /* BLOCK_BYTES and guarantees they are aligned on a BLOCK_ALIGN boundary. */
812
813 /* Use posix_memalloc if the system has it and we're using the system's
814 malloc (because our gmalloc.c routines don't have posix_memalign although
815 its memalloc could be used). */
816 #if defined (HAVE_POSIX_MEMALIGN) && defined (SYSTEM_MALLOC)
817 #define USE_POSIX_MEMALIGN 1
818 #endif
819
820 /* BLOCK_ALIGN has to be a power of 2. */
821 #define BLOCK_ALIGN (1 << 10)
822
823 /* Padding to leave at the end of a malloc'd block. This is to give
824 malloc a chance to minimize the amount of memory wasted to alignment.
825 It should be tuned to the particular malloc library used.
826 On glibc-2.3.2, malloc never tries to align, so a padding of 0 is best.
827 posix_memalign on the other hand would ideally prefer a value of 4
828 because otherwise, there's 1020 bytes wasted between each ablocks.
829 In Emacs, testing shows that those 1020 can most of the time be
830 efficiently used by malloc to place other objects, so a value of 0 can
831 still preferable unless you have a lot of aligned blocks and virtually
832 nothing else. */
833 #define BLOCK_PADDING 0
834 #define BLOCK_BYTES \
835 (BLOCK_ALIGN - sizeof (struct ablocks *) - BLOCK_PADDING)
836
837 /* Internal data structures and constants. */
838
839 #define ABLOCKS_SIZE 16
840
841 /* An aligned block of memory. */
842 struct ablock
843 {
844 union
845 {
846 char payload[BLOCK_BYTES];
847 struct ablock *next_free;
848 } x;
849 /* `abase' is the aligned base of the ablocks. */
850 /* It is overloaded to hold the virtual `busy' field that counts
851 the number of used ablock in the parent ablocks.
852 The first ablock has the `busy' field, the others have the `abase'
853 field. To tell the difference, we assume that pointers will have
854 integer values larger than 2 * ABLOCKS_SIZE. The lowest bit of `busy'
855 is used to tell whether the real base of the parent ablocks is `abase'
856 (if not, the word before the first ablock holds a pointer to the
857 real base). */
858 struct ablocks *abase;
859 /* The padding of all but the last ablock is unused. The padding of
860 the last ablock in an ablocks is not allocated. */
861 #if BLOCK_PADDING
862 char padding[BLOCK_PADDING];
863 #endif
864 };
865
866 /* A bunch of consecutive aligned blocks. */
867 struct ablocks
868 {
869 struct ablock blocks[ABLOCKS_SIZE];
870 };
871
872 /* Size of the block requested from malloc or memalign. */
873 #define ABLOCKS_BYTES (sizeof (struct ablocks) - BLOCK_PADDING)
874
875 #define ABLOCK_ABASE(block) \
876 (((uintptr_t) (block)->abase) <= (1 + 2 * ABLOCKS_SIZE) \
877 ? (struct ablocks *)(block) \
878 : (block)->abase)
879
880 /* Virtual `busy' field. */
881 #define ABLOCKS_BUSY(abase) ((abase)->blocks[0].abase)
882
883 /* Pointer to the (not necessarily aligned) malloc block. */
884 #ifdef USE_POSIX_MEMALIGN
885 #define ABLOCKS_BASE(abase) (abase)
886 #else
887 #define ABLOCKS_BASE(abase) \
888 (1 & (intptr_t) ABLOCKS_BUSY (abase) ? abase : ((void**)abase)[-1])
889 #endif
890
891 /* The list of free ablock. */
892 static struct ablock *free_ablock;
893
894 /* Allocate an aligned block of nbytes.
895 Alignment is on a multiple of BLOCK_ALIGN and `nbytes' has to be
896 smaller or equal to BLOCK_BYTES. */
897 static POINTER_TYPE *
898 lisp_align_malloc (size_t nbytes, enum mem_type type)
899 {
900 void *base, *val;
901 struct ablocks *abase;
902
903 eassert (nbytes <= BLOCK_BYTES);
904
905 MALLOC_BLOCK_INPUT;
906
907 #ifdef GC_MALLOC_CHECK
908 allocated_mem_type = type;
909 #endif
910
911 if (!free_ablock)
912 {
913 int i;
914 intptr_t aligned; /* int gets warning casting to 64-bit pointer. */
915
916 #ifdef DOUG_LEA_MALLOC
917 /* Prevent mmap'ing the chunk. Lisp data may not be mmap'ed
918 because mapped region contents are not preserved in
919 a dumped Emacs. */
920 mallopt (M_MMAP_MAX, 0);
921 #endif
922
923 #ifdef USE_POSIX_MEMALIGN
924 {
925 int err = posix_memalign (&base, BLOCK_ALIGN, ABLOCKS_BYTES);
926 if (err)
927 base = NULL;
928 abase = base;
929 }
930 #else
931 base = malloc (ABLOCKS_BYTES);
932 abase = ALIGN (base, BLOCK_ALIGN);
933 #endif
934
935 if (base == 0)
936 {
937 MALLOC_UNBLOCK_INPUT;
938 memory_full (ABLOCKS_BYTES);
939 }
940
941 aligned = (base == abase);
942 if (!aligned)
943 ((void**)abase)[-1] = base;
944
945 #ifdef DOUG_LEA_MALLOC
946 /* Back to a reasonable maximum of mmap'ed areas. */
947 mallopt (M_MMAP_MAX, MMAP_MAX_AREAS);
948 #endif
949
950 #ifndef USE_LSB_TAG
951 /* If the memory just allocated cannot be addressed thru a Lisp
952 object's pointer, and it needs to be, that's equivalent to
953 running out of memory. */
954 if (type != MEM_TYPE_NON_LISP)
955 {
956 Lisp_Object tem;
957 char *end = (char *) base + ABLOCKS_BYTES - 1;
958 XSETCONS (tem, end);
959 if ((char *) XCONS (tem) != end)
960 {
961 lisp_malloc_loser = base;
962 free (base);
963 MALLOC_UNBLOCK_INPUT;
964 memory_full (SIZE_MAX);
965 }
966 }
967 #endif
968
969 /* Initialize the blocks and put them on the free list.
970 Is `base' was not properly aligned, we can't use the last block. */
971 for (i = 0; i < (aligned ? ABLOCKS_SIZE : ABLOCKS_SIZE - 1); i++)
972 {
973 abase->blocks[i].abase = abase;
974 abase->blocks[i].x.next_free = free_ablock;
975 free_ablock = &abase->blocks[i];
976 }
977 ABLOCKS_BUSY (abase) = (struct ablocks *) aligned;
978
979 eassert (0 == ((uintptr_t) abase) % BLOCK_ALIGN);
980 eassert (ABLOCK_ABASE (&abase->blocks[3]) == abase); /* 3 is arbitrary */
981 eassert (ABLOCK_ABASE (&abase->blocks[0]) == abase);
982 eassert (ABLOCKS_BASE (abase) == base);
983 eassert (aligned == (intptr_t) ABLOCKS_BUSY (abase));
984 }
985
986 abase = ABLOCK_ABASE (free_ablock);
987 ABLOCKS_BUSY (abase) =
988 (struct ablocks *) (2 + (intptr_t) ABLOCKS_BUSY (abase));
989 val = free_ablock;
990 free_ablock = free_ablock->x.next_free;
991
992 #if GC_MARK_STACK && !defined GC_MALLOC_CHECK
993 if (type != MEM_TYPE_NON_LISP)
994 mem_insert (val, (char *) val + nbytes, type);
995 #endif
996
997 MALLOC_UNBLOCK_INPUT;
998
999 eassert (0 == ((uintptr_t) val) % BLOCK_ALIGN);
1000 return val;
1001 }
1002
1003 static void
1004 lisp_align_free (POINTER_TYPE *block)
1005 {
1006 struct ablock *ablock = block;
1007 struct ablocks *abase = ABLOCK_ABASE (ablock);
1008
1009 MALLOC_BLOCK_INPUT;
1010 #if GC_MARK_STACK && !defined GC_MALLOC_CHECK
1011 mem_delete (mem_find (block));
1012 #endif
1013 /* Put on free list. */
1014 ablock->x.next_free = free_ablock;
1015 free_ablock = ablock;
1016 /* Update busy count. */
1017 ABLOCKS_BUSY (abase) =
1018 (struct ablocks *) (-2 + (intptr_t) ABLOCKS_BUSY (abase));
1019
1020 if (2 > (intptr_t) ABLOCKS_BUSY (abase))
1021 { /* All the blocks are free. */
1022 int i = 0, aligned = (intptr_t) ABLOCKS_BUSY (abase);
1023 struct ablock **tem = &free_ablock;
1024 struct ablock *atop = &abase->blocks[aligned ? ABLOCKS_SIZE : ABLOCKS_SIZE - 1];
1025
1026 while (*tem)
1027 {
1028 if (*tem >= (struct ablock *) abase && *tem < atop)
1029 {
1030 i++;
1031 *tem = (*tem)->x.next_free;
1032 }
1033 else
1034 tem = &(*tem)->x.next_free;
1035 }
1036 eassert ((aligned & 1) == aligned);
1037 eassert (i == (aligned ? ABLOCKS_SIZE : ABLOCKS_SIZE - 1));
1038 #ifdef USE_POSIX_MEMALIGN
1039 eassert ((uintptr_t) ABLOCKS_BASE (abase) % BLOCK_ALIGN == 0);
1040 #endif
1041 free (ABLOCKS_BASE (abase));
1042 }
1043 MALLOC_UNBLOCK_INPUT;
1044 }
1045
1046 /* Return a new buffer structure allocated from the heap with
1047 a call to lisp_malloc. */
1048
1049 struct buffer *
1050 allocate_buffer (void)
1051 {
1052 struct buffer *b
1053 = (struct buffer *) lisp_malloc (sizeof (struct buffer),
1054 MEM_TYPE_BUFFER);
1055 XSETPVECTYPESIZE (b, PVEC_BUFFER,
1056 ((sizeof (struct buffer) + sizeof (EMACS_INT) - 1)
1057 / sizeof (EMACS_INT)));
1058 return b;
1059 }
1060
1061 \f
1062 #ifndef SYSTEM_MALLOC
1063
1064 /* Arranging to disable input signals while we're in malloc.
1065
1066 This only works with GNU malloc. To help out systems which can't
1067 use GNU malloc, all the calls to malloc, realloc, and free
1068 elsewhere in the code should be inside a BLOCK_INPUT/UNBLOCK_INPUT
1069 pair; unfortunately, we have no idea what C library functions
1070 might call malloc, so we can't really protect them unless you're
1071 using GNU malloc. Fortunately, most of the major operating systems
1072 can use GNU malloc. */
1073
1074 #ifndef SYNC_INPUT
1075 /* When using SYNC_INPUT, we don't call malloc from a signal handler, so
1076 there's no need to block input around malloc. */
1077
1078 #ifndef DOUG_LEA_MALLOC
1079 extern void * (*__malloc_hook) (size_t, const void *);
1080 extern void * (*__realloc_hook) (void *, size_t, const void *);
1081 extern void (*__free_hook) (void *, const void *);
1082 /* Else declared in malloc.h, perhaps with an extra arg. */
1083 #endif /* DOUG_LEA_MALLOC */
1084 static void * (*old_malloc_hook) (size_t, const void *);
1085 static void * (*old_realloc_hook) (void *, size_t, const void*);
1086 static void (*old_free_hook) (void*, const void*);
1087
1088 #ifdef DOUG_LEA_MALLOC
1089 # define BYTES_USED (mallinfo ().uordblks)
1090 #else
1091 # define BYTES_USED _bytes_used
1092 #endif
1093
1094 static __malloc_size_t bytes_used_when_reconsidered;
1095
1096 /* Value of _bytes_used, when spare_memory was freed. */
1097
1098 static __malloc_size_t bytes_used_when_full;
1099
1100 /* This function is used as the hook for free to call. */
1101
1102 static void
1103 emacs_blocked_free (void *ptr, const void *ptr2)
1104 {
1105 BLOCK_INPUT_ALLOC;
1106
1107 #ifdef GC_MALLOC_CHECK
1108 if (ptr)
1109 {
1110 struct mem_node *m;
1111
1112 m = mem_find (ptr);
1113 if (m == MEM_NIL || m->start != ptr)
1114 {
1115 fprintf (stderr,
1116 "Freeing `%p' which wasn't allocated with malloc\n", ptr);
1117 abort ();
1118 }
1119 else
1120 {
1121 /* fprintf (stderr, "free %p...%p (%p)\n", m->start, m->end, ptr); */
1122 mem_delete (m);
1123 }
1124 }
1125 #endif /* GC_MALLOC_CHECK */
1126
1127 __free_hook = old_free_hook;
1128 free (ptr);
1129
1130 /* If we released our reserve (due to running out of memory),
1131 and we have a fair amount free once again,
1132 try to set aside another reserve in case we run out once more. */
1133 if (! NILP (Vmemory_full)
1134 /* Verify there is enough space that even with the malloc
1135 hysteresis this call won't run out again.
1136 The code here is correct as long as SPARE_MEMORY
1137 is substantially larger than the block size malloc uses. */
1138 && (bytes_used_when_full
1139 > ((bytes_used_when_reconsidered = BYTES_USED)
1140 + max (malloc_hysteresis, 4) * SPARE_MEMORY)))
1141 refill_memory_reserve ();
1142
1143 __free_hook = emacs_blocked_free;
1144 UNBLOCK_INPUT_ALLOC;
1145 }
1146
1147
1148 /* This function is the malloc hook that Emacs uses. */
1149
1150 static void *
1151 emacs_blocked_malloc (size_t size, const void *ptr)
1152 {
1153 void *value;
1154
1155 BLOCK_INPUT_ALLOC;
1156 __malloc_hook = old_malloc_hook;
1157 #ifdef DOUG_LEA_MALLOC
1158 /* Segfaults on my system. --lorentey */
1159 /* mallopt (M_TOP_PAD, malloc_hysteresis * 4096); */
1160 #else
1161 __malloc_extra_blocks = malloc_hysteresis;
1162 #endif
1163
1164 value = (void *) malloc (size);
1165
1166 #ifdef GC_MALLOC_CHECK
1167 {
1168 struct mem_node *m = mem_find (value);
1169 if (m != MEM_NIL)
1170 {
1171 fprintf (stderr, "Malloc returned %p which is already in use\n",
1172 value);
1173 fprintf (stderr, "Region in use is %p...%p, %u bytes, type %d\n",
1174 m->start, m->end, (char *) m->end - (char *) m->start,
1175 m->type);
1176 abort ();
1177 }
1178
1179 if (!dont_register_blocks)
1180 {
1181 mem_insert (value, (char *) value + max (1, size), allocated_mem_type);
1182 allocated_mem_type = MEM_TYPE_NON_LISP;
1183 }
1184 }
1185 #endif /* GC_MALLOC_CHECK */
1186
1187 __malloc_hook = emacs_blocked_malloc;
1188 UNBLOCK_INPUT_ALLOC;
1189
1190 /* fprintf (stderr, "%p malloc\n", value); */
1191 return value;
1192 }
1193
1194
1195 /* This function is the realloc hook that Emacs uses. */
1196
1197 static void *
1198 emacs_blocked_realloc (void *ptr, size_t size, const void *ptr2)
1199 {
1200 void *value;
1201
1202 BLOCK_INPUT_ALLOC;
1203 __realloc_hook = old_realloc_hook;
1204
1205 #ifdef GC_MALLOC_CHECK
1206 if (ptr)
1207 {
1208 struct mem_node *m = mem_find (ptr);
1209 if (m == MEM_NIL || m->start != ptr)
1210 {
1211 fprintf (stderr,
1212 "Realloc of %p which wasn't allocated with malloc\n",
1213 ptr);
1214 abort ();
1215 }
1216
1217 mem_delete (m);
1218 }
1219
1220 /* fprintf (stderr, "%p -> realloc\n", ptr); */
1221
1222 /* Prevent malloc from registering blocks. */
1223 dont_register_blocks = 1;
1224 #endif /* GC_MALLOC_CHECK */
1225
1226 value = (void *) realloc (ptr, size);
1227
1228 #ifdef GC_MALLOC_CHECK
1229 dont_register_blocks = 0;
1230
1231 {
1232 struct mem_node *m = mem_find (value);
1233 if (m != MEM_NIL)
1234 {
1235 fprintf (stderr, "Realloc returns memory that is already in use\n");
1236 abort ();
1237 }
1238
1239 /* Can't handle zero size regions in the red-black tree. */
1240 mem_insert (value, (char *) value + max (size, 1), MEM_TYPE_NON_LISP);
1241 }
1242
1243 /* fprintf (stderr, "%p <- realloc\n", value); */
1244 #endif /* GC_MALLOC_CHECK */
1245
1246 __realloc_hook = emacs_blocked_realloc;
1247 UNBLOCK_INPUT_ALLOC;
1248
1249 return value;
1250 }
1251
1252
1253 #ifdef HAVE_GTK_AND_PTHREAD
1254 /* Called from Fdump_emacs so that when the dumped Emacs starts, it has a
1255 normal malloc. Some thread implementations need this as they call
1256 malloc before main. The pthread_self call in BLOCK_INPUT_ALLOC then
1257 calls malloc because it is the first call, and we have an endless loop. */
1258
1259 void
1260 reset_malloc_hooks ()
1261 {
1262 __free_hook = old_free_hook;
1263 __malloc_hook = old_malloc_hook;
1264 __realloc_hook = old_realloc_hook;
1265 }
1266 #endif /* HAVE_GTK_AND_PTHREAD */
1267
1268
1269 /* Called from main to set up malloc to use our hooks. */
1270
1271 void
1272 uninterrupt_malloc (void)
1273 {
1274 #ifdef HAVE_GTK_AND_PTHREAD
1275 #ifdef DOUG_LEA_MALLOC
1276 pthread_mutexattr_t attr;
1277
1278 /* GLIBC has a faster way to do this, but lets keep it portable.
1279 This is according to the Single UNIX Specification. */
1280 pthread_mutexattr_init (&attr);
1281 pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_RECURSIVE);
1282 pthread_mutex_init (&alloc_mutex, &attr);
1283 #else /* !DOUG_LEA_MALLOC */
1284 /* Some systems such as Solaris 2.6 don't have a recursive mutex,
1285 and the bundled gmalloc.c doesn't require it. */
1286 pthread_mutex_init (&alloc_mutex, NULL);
1287 #endif /* !DOUG_LEA_MALLOC */
1288 #endif /* HAVE_GTK_AND_PTHREAD */
1289
1290 if (__free_hook != emacs_blocked_free)
1291 old_free_hook = __free_hook;
1292 __free_hook = emacs_blocked_free;
1293
1294 if (__malloc_hook != emacs_blocked_malloc)
1295 old_malloc_hook = __malloc_hook;
1296 __malloc_hook = emacs_blocked_malloc;
1297
1298 if (__realloc_hook != emacs_blocked_realloc)
1299 old_realloc_hook = __realloc_hook;
1300 __realloc_hook = emacs_blocked_realloc;
1301 }
1302
1303 #endif /* not SYNC_INPUT */
1304 #endif /* not SYSTEM_MALLOC */
1305
1306
1307 \f
1308 /***********************************************************************
1309 Interval Allocation
1310 ***********************************************************************/
1311
1312 /* Number of intervals allocated in an interval_block structure.
1313 The 1020 is 1024 minus malloc overhead. */
1314
1315 #define INTERVAL_BLOCK_SIZE \
1316 ((1020 - sizeof (struct interval_block *)) / sizeof (struct interval))
1317
1318 /* Intervals are allocated in chunks in form of an interval_block
1319 structure. */
1320
1321 struct interval_block
1322 {
1323 /* Place `intervals' first, to preserve alignment. */
1324 struct interval intervals[INTERVAL_BLOCK_SIZE];
1325 struct interval_block *next;
1326 };
1327
1328 /* Current interval block. Its `next' pointer points to older
1329 blocks. */
1330
1331 static struct interval_block *interval_block;
1332
1333 /* Index in interval_block above of the next unused interval
1334 structure. */
1335
1336 static int interval_block_index;
1337
1338 /* Number of free and live intervals. */
1339
1340 static int total_free_intervals, total_intervals;
1341
1342 /* List of free intervals. */
1343
1344 static INTERVAL interval_free_list;
1345
1346 /* Total number of interval blocks now in use. */
1347
1348 static int n_interval_blocks;
1349
1350
1351 /* Initialize interval allocation. */
1352
1353 static void
1354 init_intervals (void)
1355 {
1356 interval_block = NULL;
1357 interval_block_index = INTERVAL_BLOCK_SIZE;
1358 interval_free_list = 0;
1359 n_interval_blocks = 0;
1360 }
1361
1362
1363 /* Return a new interval. */
1364
1365 INTERVAL
1366 make_interval (void)
1367 {
1368 INTERVAL val;
1369
1370 /* eassert (!handling_signal); */
1371
1372 MALLOC_BLOCK_INPUT;
1373
1374 if (interval_free_list)
1375 {
1376 val = interval_free_list;
1377 interval_free_list = INTERVAL_PARENT (interval_free_list);
1378 }
1379 else
1380 {
1381 if (interval_block_index == INTERVAL_BLOCK_SIZE)
1382 {
1383 register struct interval_block *newi;
1384
1385 newi = (struct interval_block *) lisp_malloc (sizeof *newi,
1386 MEM_TYPE_NON_LISP);
1387
1388 newi->next = interval_block;
1389 interval_block = newi;
1390 interval_block_index = 0;
1391 n_interval_blocks++;
1392 }
1393 val = &interval_block->intervals[interval_block_index++];
1394 }
1395
1396 MALLOC_UNBLOCK_INPUT;
1397
1398 consing_since_gc += sizeof (struct interval);
1399 intervals_consed++;
1400 RESET_INTERVAL (val);
1401 val->gcmarkbit = 0;
1402 return val;
1403 }
1404
1405
1406 /* Mark Lisp objects in interval I. */
1407
1408 static void
1409 mark_interval (register INTERVAL i, Lisp_Object dummy)
1410 {
1411 eassert (!i->gcmarkbit); /* Intervals are never shared. */
1412 i->gcmarkbit = 1;
1413 mark_object (i->plist);
1414 }
1415
1416
1417 /* Mark the interval tree rooted in TREE. Don't call this directly;
1418 use the macro MARK_INTERVAL_TREE instead. */
1419
1420 static void
1421 mark_interval_tree (register INTERVAL tree)
1422 {
1423 /* No need to test if this tree has been marked already; this
1424 function is always called through the MARK_INTERVAL_TREE macro,
1425 which takes care of that. */
1426
1427 traverse_intervals_noorder (tree, mark_interval, Qnil);
1428 }
1429
1430
1431 /* Mark the interval tree rooted in I. */
1432
1433 #define MARK_INTERVAL_TREE(i) \
1434 do { \
1435 if (!NULL_INTERVAL_P (i) && !i->gcmarkbit) \
1436 mark_interval_tree (i); \
1437 } while (0)
1438
1439
1440 #define UNMARK_BALANCE_INTERVALS(i) \
1441 do { \
1442 if (! NULL_INTERVAL_P (i)) \
1443 (i) = balance_intervals (i); \
1444 } while (0)
1445
1446 \f
1447 /* Number support. If USE_LISP_UNION_TYPE is in effect, we
1448 can't create number objects in macros. */
1449 #ifndef make_number
1450 Lisp_Object
1451 make_number (EMACS_INT n)
1452 {
1453 Lisp_Object obj;
1454 obj.s.val = n;
1455 obj.s.type = Lisp_Int;
1456 return obj;
1457 }
1458 #endif
1459 \f
1460 /***********************************************************************
1461 String Allocation
1462 ***********************************************************************/
1463
1464 /* Lisp_Strings are allocated in string_block structures. When a new
1465 string_block is allocated, all the Lisp_Strings it contains are
1466 added to a free-list string_free_list. When a new Lisp_String is
1467 needed, it is taken from that list. During the sweep phase of GC,
1468 string_blocks that are entirely free are freed, except two which
1469 we keep.
1470
1471 String data is allocated from sblock structures. Strings larger
1472 than LARGE_STRING_BYTES, get their own sblock, data for smaller
1473 strings is sub-allocated out of sblocks of size SBLOCK_SIZE.
1474
1475 Sblocks consist internally of sdata structures, one for each
1476 Lisp_String. The sdata structure points to the Lisp_String it
1477 belongs to. The Lisp_String points back to the `u.data' member of
1478 its sdata structure.
1479
1480 When a Lisp_String is freed during GC, it is put back on
1481 string_free_list, and its `data' member and its sdata's `string'
1482 pointer is set to null. The size of the string is recorded in the
1483 `u.nbytes' member of the sdata. So, sdata structures that are no
1484 longer used, can be easily recognized, and it's easy to compact the
1485 sblocks of small strings which we do in compact_small_strings. */
1486
1487 /* Size in bytes of an sblock structure used for small strings. This
1488 is 8192 minus malloc overhead. */
1489
1490 #define SBLOCK_SIZE 8188
1491
1492 /* Strings larger than this are considered large strings. String data
1493 for large strings is allocated from individual sblocks. */
1494
1495 #define LARGE_STRING_BYTES 1024
1496
1497 /* Structure describing string memory sub-allocated from an sblock.
1498 This is where the contents of Lisp strings are stored. */
1499
1500 struct sdata
1501 {
1502 /* Back-pointer to the string this sdata belongs to. If null, this
1503 structure is free, and the NBYTES member of the union below
1504 contains the string's byte size (the same value that STRING_BYTES
1505 would return if STRING were non-null). If non-null, STRING_BYTES
1506 (STRING) is the size of the data, and DATA contains the string's
1507 contents. */
1508 struct Lisp_String *string;
1509
1510 #ifdef GC_CHECK_STRING_BYTES
1511
1512 EMACS_INT nbytes;
1513 unsigned char data[1];
1514
1515 #define SDATA_NBYTES(S) (S)->nbytes
1516 #define SDATA_DATA(S) (S)->data
1517 #define SDATA_SELECTOR(member) member
1518
1519 #else /* not GC_CHECK_STRING_BYTES */
1520
1521 union
1522 {
1523 /* When STRING is non-null. */
1524 unsigned char data[1];
1525
1526 /* When STRING is null. */
1527 EMACS_INT nbytes;
1528 } u;
1529
1530 #define SDATA_NBYTES(S) (S)->u.nbytes
1531 #define SDATA_DATA(S) (S)->u.data
1532 #define SDATA_SELECTOR(member) u.member
1533
1534 #endif /* not GC_CHECK_STRING_BYTES */
1535
1536 #define SDATA_DATA_OFFSET offsetof (struct sdata, SDATA_SELECTOR (data))
1537 };
1538
1539
1540 /* Structure describing a block of memory which is sub-allocated to
1541 obtain string data memory for strings. Blocks for small strings
1542 are of fixed size SBLOCK_SIZE. Blocks for large strings are made
1543 as large as needed. */
1544
1545 struct sblock
1546 {
1547 /* Next in list. */
1548 struct sblock *next;
1549
1550 /* Pointer to the next free sdata block. This points past the end
1551 of the sblock if there isn't any space left in this block. */
1552 struct sdata *next_free;
1553
1554 /* Start of data. */
1555 struct sdata first_data;
1556 };
1557
1558 /* Number of Lisp strings in a string_block structure. The 1020 is
1559 1024 minus malloc overhead. */
1560
1561 #define STRING_BLOCK_SIZE \
1562 ((1020 - sizeof (struct string_block *)) / sizeof (struct Lisp_String))
1563
1564 /* Structure describing a block from which Lisp_String structures
1565 are allocated. */
1566
1567 struct string_block
1568 {
1569 /* Place `strings' first, to preserve alignment. */
1570 struct Lisp_String strings[STRING_BLOCK_SIZE];
1571 struct string_block *next;
1572 };
1573
1574 /* Head and tail of the list of sblock structures holding Lisp string
1575 data. We always allocate from current_sblock. The NEXT pointers
1576 in the sblock structures go from oldest_sblock to current_sblock. */
1577
1578 static struct sblock *oldest_sblock, *current_sblock;
1579
1580 /* List of sblocks for large strings. */
1581
1582 static struct sblock *large_sblocks;
1583
1584 /* List of string_block structures, and how many there are. */
1585
1586 static struct string_block *string_blocks;
1587 static int n_string_blocks;
1588
1589 /* Free-list of Lisp_Strings. */
1590
1591 static struct Lisp_String *string_free_list;
1592
1593 /* Number of live and free Lisp_Strings. */
1594
1595 static int total_strings, total_free_strings;
1596
1597 /* Number of bytes used by live strings. */
1598
1599 static EMACS_INT total_string_size;
1600
1601 /* Given a pointer to a Lisp_String S which is on the free-list
1602 string_free_list, return a pointer to its successor in the
1603 free-list. */
1604
1605 #define NEXT_FREE_LISP_STRING(S) (*(struct Lisp_String **) (S))
1606
1607 /* Return a pointer to the sdata structure belonging to Lisp string S.
1608 S must be live, i.e. S->data must not be null. S->data is actually
1609 a pointer to the `u.data' member of its sdata structure; the
1610 structure starts at a constant offset in front of that. */
1611
1612 #define SDATA_OF_STRING(S) ((struct sdata *) ((S)->data - SDATA_DATA_OFFSET))
1613
1614
1615 #ifdef GC_CHECK_STRING_OVERRUN
1616
1617 /* We check for overrun in string data blocks by appending a small
1618 "cookie" after each allocated string data block, and check for the
1619 presence of this cookie during GC. */
1620
1621 #define GC_STRING_OVERRUN_COOKIE_SIZE 4
1622 static char const string_overrun_cookie[GC_STRING_OVERRUN_COOKIE_SIZE] =
1623 { '\xde', '\xad', '\xbe', '\xef' };
1624
1625 #else
1626 #define GC_STRING_OVERRUN_COOKIE_SIZE 0
1627 #endif
1628
1629 /* Value is the size of an sdata structure large enough to hold NBYTES
1630 bytes of string data. The value returned includes a terminating
1631 NUL byte, the size of the sdata structure, and padding. */
1632
1633 #ifdef GC_CHECK_STRING_BYTES
1634
1635 #define SDATA_SIZE(NBYTES) \
1636 ((SDATA_DATA_OFFSET \
1637 + (NBYTES) + 1 \
1638 + sizeof (EMACS_INT) - 1) \
1639 & ~(sizeof (EMACS_INT) - 1))
1640
1641 #else /* not GC_CHECK_STRING_BYTES */
1642
1643 /* The 'max' reserves space for the nbytes union member even when NBYTES + 1 is
1644 less than the size of that member. The 'max' is not needed when
1645 SDATA_DATA_OFFSET is a multiple of sizeof (EMACS_INT), because then the
1646 alignment code reserves enough space. */
1647
1648 #define SDATA_SIZE(NBYTES) \
1649 ((SDATA_DATA_OFFSET \
1650 + (SDATA_DATA_OFFSET % sizeof (EMACS_INT) == 0 \
1651 ? NBYTES \
1652 : max (NBYTES, sizeof (EMACS_INT) - 1)) \
1653 + 1 \
1654 + sizeof (EMACS_INT) - 1) \
1655 & ~(sizeof (EMACS_INT) - 1))
1656
1657 #endif /* not GC_CHECK_STRING_BYTES */
1658
1659 /* Extra bytes to allocate for each string. */
1660
1661 #define GC_STRING_EXTRA (GC_STRING_OVERRUN_COOKIE_SIZE)
1662
1663 /* Initialize string allocation. Called from init_alloc_once. */
1664
1665 static void
1666 init_strings (void)
1667 {
1668 total_strings = total_free_strings = total_string_size = 0;
1669 oldest_sblock = current_sblock = large_sblocks = NULL;
1670 string_blocks = NULL;
1671 n_string_blocks = 0;
1672 string_free_list = NULL;
1673 empty_unibyte_string = make_pure_string ("", 0, 0, 0);
1674 empty_multibyte_string = make_pure_string ("", 0, 0, 1);
1675 }
1676
1677
1678 #ifdef GC_CHECK_STRING_BYTES
1679
1680 static int check_string_bytes_count;
1681
1682 #define CHECK_STRING_BYTES(S) STRING_BYTES (S)
1683
1684
1685 /* Like GC_STRING_BYTES, but with debugging check. */
1686
1687 EMACS_INT
1688 string_bytes (struct Lisp_String *s)
1689 {
1690 EMACS_INT nbytes =
1691 (s->size_byte < 0 ? s->size & ~ARRAY_MARK_FLAG : s->size_byte);
1692
1693 if (!PURE_POINTER_P (s)
1694 && s->data
1695 && nbytes != SDATA_NBYTES (SDATA_OF_STRING (s)))
1696 abort ();
1697 return nbytes;
1698 }
1699
1700 /* Check validity of Lisp strings' string_bytes member in B. */
1701
1702 static void
1703 check_sblock (struct sblock *b)
1704 {
1705 struct sdata *from, *end, *from_end;
1706
1707 end = b->next_free;
1708
1709 for (from = &b->first_data; from < end; from = from_end)
1710 {
1711 /* Compute the next FROM here because copying below may
1712 overwrite data we need to compute it. */
1713 EMACS_INT nbytes;
1714
1715 /* Check that the string size recorded in the string is the
1716 same as the one recorded in the sdata structure. */
1717 if (from->string)
1718 CHECK_STRING_BYTES (from->string);
1719
1720 if (from->string)
1721 nbytes = GC_STRING_BYTES (from->string);
1722 else
1723 nbytes = SDATA_NBYTES (from);
1724
1725 nbytes = SDATA_SIZE (nbytes);
1726 from_end = (struct sdata *) ((char *) from + nbytes + GC_STRING_EXTRA);
1727 }
1728 }
1729
1730
1731 /* Check validity of Lisp strings' string_bytes member. ALL_P
1732 non-zero means check all strings, otherwise check only most
1733 recently allocated strings. Used for hunting a bug. */
1734
1735 static void
1736 check_string_bytes (int all_p)
1737 {
1738 if (all_p)
1739 {
1740 struct sblock *b;
1741
1742 for (b = large_sblocks; b; b = b->next)
1743 {
1744 struct Lisp_String *s = b->first_data.string;
1745 if (s)
1746 CHECK_STRING_BYTES (s);
1747 }
1748
1749 for (b = oldest_sblock; b; b = b->next)
1750 check_sblock (b);
1751 }
1752 else
1753 check_sblock (current_sblock);
1754 }
1755
1756 #endif /* GC_CHECK_STRING_BYTES */
1757
1758 #ifdef GC_CHECK_STRING_FREE_LIST
1759
1760 /* Walk through the string free list looking for bogus next pointers.
1761 This may catch buffer overrun from a previous string. */
1762
1763 static void
1764 check_string_free_list (void)
1765 {
1766 struct Lisp_String *s;
1767
1768 /* Pop a Lisp_String off the free-list. */
1769 s = string_free_list;
1770 while (s != NULL)
1771 {
1772 if ((uintptr_t) s < 1024)
1773 abort();
1774 s = NEXT_FREE_LISP_STRING (s);
1775 }
1776 }
1777 #else
1778 #define check_string_free_list()
1779 #endif
1780
1781 /* Return a new Lisp_String. */
1782
1783 static struct Lisp_String *
1784 allocate_string (void)
1785 {
1786 struct Lisp_String *s;
1787
1788 /* eassert (!handling_signal); */
1789
1790 MALLOC_BLOCK_INPUT;
1791
1792 /* If the free-list is empty, allocate a new string_block, and
1793 add all the Lisp_Strings in it to the free-list. */
1794 if (string_free_list == NULL)
1795 {
1796 struct string_block *b;
1797 int i;
1798
1799 b = (struct string_block *) lisp_malloc (sizeof *b, MEM_TYPE_STRING);
1800 memset (b, 0, sizeof *b);
1801 b->next = string_blocks;
1802 string_blocks = b;
1803 ++n_string_blocks;
1804
1805 for (i = STRING_BLOCK_SIZE - 1; i >= 0; --i)
1806 {
1807 s = b->strings + i;
1808 NEXT_FREE_LISP_STRING (s) = string_free_list;
1809 string_free_list = s;
1810 }
1811
1812 total_free_strings += STRING_BLOCK_SIZE;
1813 }
1814
1815 check_string_free_list ();
1816
1817 /* Pop a Lisp_String off the free-list. */
1818 s = string_free_list;
1819 string_free_list = NEXT_FREE_LISP_STRING (s);
1820
1821 MALLOC_UNBLOCK_INPUT;
1822
1823 /* Probably not strictly necessary, but play it safe. */
1824 memset (s, 0, sizeof *s);
1825
1826 --total_free_strings;
1827 ++total_strings;
1828 ++strings_consed;
1829 consing_since_gc += sizeof *s;
1830
1831 #ifdef GC_CHECK_STRING_BYTES
1832 if (!noninteractive)
1833 {
1834 if (++check_string_bytes_count == 200)
1835 {
1836 check_string_bytes_count = 0;
1837 check_string_bytes (1);
1838 }
1839 else
1840 check_string_bytes (0);
1841 }
1842 #endif /* GC_CHECK_STRING_BYTES */
1843
1844 return s;
1845 }
1846
1847
1848 /* Set up Lisp_String S for holding NCHARS characters, NBYTES bytes,
1849 plus a NUL byte at the end. Allocate an sdata structure for S, and
1850 set S->data to its `u.data' member. Store a NUL byte at the end of
1851 S->data. Set S->size to NCHARS and S->size_byte to NBYTES. Free
1852 S->data if it was initially non-null. */
1853
1854 void
1855 allocate_string_data (struct Lisp_String *s,
1856 EMACS_INT nchars, EMACS_INT nbytes)
1857 {
1858 struct sdata *data, *old_data;
1859 struct sblock *b;
1860 EMACS_INT needed, old_nbytes;
1861
1862 /* Determine the number of bytes needed to store NBYTES bytes
1863 of string data. */
1864 needed = SDATA_SIZE (nbytes);
1865 old_data = s->data ? SDATA_OF_STRING (s) : NULL;
1866 old_nbytes = GC_STRING_BYTES (s);
1867
1868 MALLOC_BLOCK_INPUT;
1869
1870 if (nbytes > LARGE_STRING_BYTES)
1871 {
1872 size_t size = offsetof (struct sblock, first_data) + needed;
1873
1874 #ifdef DOUG_LEA_MALLOC
1875 /* Prevent mmap'ing the chunk. Lisp data may not be mmap'ed
1876 because mapped region contents are not preserved in
1877 a dumped Emacs.
1878
1879 In case you think of allowing it in a dumped Emacs at the
1880 cost of not being able to re-dump, there's another reason:
1881 mmap'ed data typically have an address towards the top of the
1882 address space, which won't fit into an EMACS_INT (at least on
1883 32-bit systems with the current tagging scheme). --fx */
1884 mallopt (M_MMAP_MAX, 0);
1885 #endif
1886
1887 b = (struct sblock *) lisp_malloc (size + GC_STRING_EXTRA, MEM_TYPE_NON_LISP);
1888
1889 #ifdef DOUG_LEA_MALLOC
1890 /* Back to a reasonable maximum of mmap'ed areas. */
1891 mallopt (M_MMAP_MAX, MMAP_MAX_AREAS);
1892 #endif
1893
1894 b->next_free = &b->first_data;
1895 b->first_data.string = NULL;
1896 b->next = large_sblocks;
1897 large_sblocks = b;
1898 }
1899 else if (current_sblock == NULL
1900 || (((char *) current_sblock + SBLOCK_SIZE
1901 - (char *) current_sblock->next_free)
1902 < (needed + GC_STRING_EXTRA)))
1903 {
1904 /* Not enough room in the current sblock. */
1905 b = (struct sblock *) lisp_malloc (SBLOCK_SIZE, MEM_TYPE_NON_LISP);
1906 b->next_free = &b->first_data;
1907 b->first_data.string = NULL;
1908 b->next = NULL;
1909
1910 if (current_sblock)
1911 current_sblock->next = b;
1912 else
1913 oldest_sblock = b;
1914 current_sblock = b;
1915 }
1916 else
1917 b = current_sblock;
1918
1919 data = b->next_free;
1920 b->next_free = (struct sdata *) ((char *) data + needed + GC_STRING_EXTRA);
1921
1922 MALLOC_UNBLOCK_INPUT;
1923
1924 data->string = s;
1925 s->data = SDATA_DATA (data);
1926 #ifdef GC_CHECK_STRING_BYTES
1927 SDATA_NBYTES (data) = nbytes;
1928 #endif
1929 s->size = nchars;
1930 s->size_byte = nbytes;
1931 s->data[nbytes] = '\0';
1932 #ifdef GC_CHECK_STRING_OVERRUN
1933 memcpy ((char *) data + needed, string_overrun_cookie,
1934 GC_STRING_OVERRUN_COOKIE_SIZE);
1935 #endif
1936
1937 /* If S had already data assigned, mark that as free by setting its
1938 string back-pointer to null, and recording the size of the data
1939 in it. */
1940 if (old_data)
1941 {
1942 SDATA_NBYTES (old_data) = old_nbytes;
1943 old_data->string = NULL;
1944 }
1945
1946 consing_since_gc += needed;
1947 }
1948
1949
1950 /* Sweep and compact strings. */
1951
1952 static void
1953 sweep_strings (void)
1954 {
1955 struct string_block *b, *next;
1956 struct string_block *live_blocks = NULL;
1957
1958 string_free_list = NULL;
1959 total_strings = total_free_strings = 0;
1960 total_string_size = 0;
1961
1962 /* Scan strings_blocks, free Lisp_Strings that aren't marked. */
1963 for (b = string_blocks; b; b = next)
1964 {
1965 int i, nfree = 0;
1966 struct Lisp_String *free_list_before = string_free_list;
1967
1968 next = b->next;
1969
1970 for (i = 0; i < STRING_BLOCK_SIZE; ++i)
1971 {
1972 struct Lisp_String *s = b->strings + i;
1973
1974 if (s->data)
1975 {
1976 /* String was not on free-list before. */
1977 if (STRING_MARKED_P (s))
1978 {
1979 /* String is live; unmark it and its intervals. */
1980 UNMARK_STRING (s);
1981
1982 if (!NULL_INTERVAL_P (s->intervals))
1983 UNMARK_BALANCE_INTERVALS (s->intervals);
1984
1985 ++total_strings;
1986 total_string_size += STRING_BYTES (s);
1987 }
1988 else
1989 {
1990 /* String is dead. Put it on the free-list. */
1991 struct sdata *data = SDATA_OF_STRING (s);
1992
1993 /* Save the size of S in its sdata so that we know
1994 how large that is. Reset the sdata's string
1995 back-pointer so that we know it's free. */
1996 #ifdef GC_CHECK_STRING_BYTES
1997 if (GC_STRING_BYTES (s) != SDATA_NBYTES (data))
1998 abort ();
1999 #else
2000 data->u.nbytes = GC_STRING_BYTES (s);
2001 #endif
2002 data->string = NULL;
2003
2004 /* Reset the strings's `data' member so that we
2005 know it's free. */
2006 s->data = NULL;
2007
2008 /* Put the string on the free-list. */
2009 NEXT_FREE_LISP_STRING (s) = string_free_list;
2010 string_free_list = s;
2011 ++nfree;
2012 }
2013 }
2014 else
2015 {
2016 /* S was on the free-list before. Put it there again. */
2017 NEXT_FREE_LISP_STRING (s) = string_free_list;
2018 string_free_list = s;
2019 ++nfree;
2020 }
2021 }
2022
2023 /* Free blocks that contain free Lisp_Strings only, except
2024 the first two of them. */
2025 if (nfree == STRING_BLOCK_SIZE
2026 && total_free_strings > STRING_BLOCK_SIZE)
2027 {
2028 lisp_free (b);
2029 --n_string_blocks;
2030 string_free_list = free_list_before;
2031 }
2032 else
2033 {
2034 total_free_strings += nfree;
2035 b->next = live_blocks;
2036 live_blocks = b;
2037 }
2038 }
2039
2040 check_string_free_list ();
2041
2042 string_blocks = live_blocks;
2043 free_large_strings ();
2044 compact_small_strings ();
2045
2046 check_string_free_list ();
2047 }
2048
2049
2050 /* Free dead large strings. */
2051
2052 static void
2053 free_large_strings (void)
2054 {
2055 struct sblock *b, *next;
2056 struct sblock *live_blocks = NULL;
2057
2058 for (b = large_sblocks; b; b = next)
2059 {
2060 next = b->next;
2061
2062 if (b->first_data.string == NULL)
2063 lisp_free (b);
2064 else
2065 {
2066 b->next = live_blocks;
2067 live_blocks = b;
2068 }
2069 }
2070
2071 large_sblocks = live_blocks;
2072 }
2073
2074
2075 /* Compact data of small strings. Free sblocks that don't contain
2076 data of live strings after compaction. */
2077
2078 static void
2079 compact_small_strings (void)
2080 {
2081 struct sblock *b, *tb, *next;
2082 struct sdata *from, *to, *end, *tb_end;
2083 struct sdata *to_end, *from_end;
2084
2085 /* TB is the sblock we copy to, TO is the sdata within TB we copy
2086 to, and TB_END is the end of TB. */
2087 tb = oldest_sblock;
2088 tb_end = (struct sdata *) ((char *) tb + SBLOCK_SIZE);
2089 to = &tb->first_data;
2090
2091 /* Step through the blocks from the oldest to the youngest. We
2092 expect that old blocks will stabilize over time, so that less
2093 copying will happen this way. */
2094 for (b = oldest_sblock; b; b = b->next)
2095 {
2096 end = b->next_free;
2097 xassert ((char *) end <= (char *) b + SBLOCK_SIZE);
2098
2099 for (from = &b->first_data; from < end; from = from_end)
2100 {
2101 /* Compute the next FROM here because copying below may
2102 overwrite data we need to compute it. */
2103 EMACS_INT nbytes;
2104
2105 #ifdef GC_CHECK_STRING_BYTES
2106 /* Check that the string size recorded in the string is the
2107 same as the one recorded in the sdata structure. */
2108 if (from->string
2109 && GC_STRING_BYTES (from->string) != SDATA_NBYTES (from))
2110 abort ();
2111 #endif /* GC_CHECK_STRING_BYTES */
2112
2113 if (from->string)
2114 nbytes = GC_STRING_BYTES (from->string);
2115 else
2116 nbytes = SDATA_NBYTES (from);
2117
2118 if (nbytes > LARGE_STRING_BYTES)
2119 abort ();
2120
2121 nbytes = SDATA_SIZE (nbytes);
2122 from_end = (struct sdata *) ((char *) from + nbytes + GC_STRING_EXTRA);
2123
2124 #ifdef GC_CHECK_STRING_OVERRUN
2125 if (memcmp (string_overrun_cookie,
2126 (char *) from_end - GC_STRING_OVERRUN_COOKIE_SIZE,
2127 GC_STRING_OVERRUN_COOKIE_SIZE))
2128 abort ();
2129 #endif
2130
2131 /* FROM->string non-null means it's alive. Copy its data. */
2132 if (from->string)
2133 {
2134 /* If TB is full, proceed with the next sblock. */
2135 to_end = (struct sdata *) ((char *) to + nbytes + GC_STRING_EXTRA);
2136 if (to_end > tb_end)
2137 {
2138 tb->next_free = to;
2139 tb = tb->next;
2140 tb_end = (struct sdata *) ((char *) tb + SBLOCK_SIZE);
2141 to = &tb->first_data;
2142 to_end = (struct sdata *) ((char *) to + nbytes + GC_STRING_EXTRA);
2143 }
2144
2145 /* Copy, and update the string's `data' pointer. */
2146 if (from != to)
2147 {
2148 xassert (tb != b || to < from);
2149 memmove (to, from, nbytes + GC_STRING_EXTRA);
2150 to->string->data = SDATA_DATA (to);
2151 }
2152
2153 /* Advance past the sdata we copied to. */
2154 to = to_end;
2155 }
2156 }
2157 }
2158
2159 /* The rest of the sblocks following TB don't contain live data, so
2160 we can free them. */
2161 for (b = tb->next; b; b = next)
2162 {
2163 next = b->next;
2164 lisp_free (b);
2165 }
2166
2167 tb->next_free = to;
2168 tb->next = NULL;
2169 current_sblock = tb;
2170 }
2171
2172 void
2173 string_overflow (void)
2174 {
2175 error ("Maximum string size exceeded");
2176 }
2177
2178 DEFUN ("make-string", Fmake_string, Smake_string, 2, 2, 0,
2179 doc: /* Return a newly created string of length LENGTH, with INIT in each element.
2180 LENGTH must be an integer.
2181 INIT must be an integer that represents a character. */)
2182 (Lisp_Object length, Lisp_Object init)
2183 {
2184 register Lisp_Object val;
2185 register unsigned char *p, *end;
2186 int c;
2187 EMACS_INT nbytes;
2188
2189 CHECK_NATNUM (length);
2190 CHECK_NUMBER (init);
2191
2192 c = XINT (init);
2193 if (ASCII_CHAR_P (c))
2194 {
2195 nbytes = XINT (length);
2196 val = make_uninit_string (nbytes);
2197 p = SDATA (val);
2198 end = p + SCHARS (val);
2199 while (p != end)
2200 *p++ = c;
2201 }
2202 else
2203 {
2204 unsigned char str[MAX_MULTIBYTE_LENGTH];
2205 int len = CHAR_STRING (c, str);
2206 EMACS_INT string_len = XINT (length);
2207
2208 if (string_len > MOST_POSITIVE_FIXNUM / len)
2209 string_overflow ();
2210 nbytes = len * string_len;
2211 val = make_uninit_multibyte_string (string_len, nbytes);
2212 p = SDATA (val);
2213 end = p + nbytes;
2214 while (p != end)
2215 {
2216 memcpy (p, str, len);
2217 p += len;
2218 }
2219 }
2220
2221 *p = 0;
2222 return val;
2223 }
2224
2225
2226 DEFUN ("make-bool-vector", Fmake_bool_vector, Smake_bool_vector, 2, 2, 0,
2227 doc: /* Return a new bool-vector of length LENGTH, using INIT for each element.
2228 LENGTH must be a number. INIT matters only in whether it is t or nil. */)
2229 (Lisp_Object length, Lisp_Object init)
2230 {
2231 register Lisp_Object val;
2232 struct Lisp_Bool_Vector *p;
2233 int real_init, i;
2234 EMACS_INT length_in_chars, length_in_elts;
2235 int bits_per_value;
2236
2237 CHECK_NATNUM (length);
2238
2239 bits_per_value = sizeof (EMACS_INT) * BOOL_VECTOR_BITS_PER_CHAR;
2240
2241 length_in_elts = (XFASTINT (length) + bits_per_value - 1) / bits_per_value;
2242 length_in_chars = ((XFASTINT (length) + BOOL_VECTOR_BITS_PER_CHAR - 1)
2243 / BOOL_VECTOR_BITS_PER_CHAR);
2244
2245 /* We must allocate one more elements than LENGTH_IN_ELTS for the
2246 slot `size' of the struct Lisp_Bool_Vector. */
2247 val = Fmake_vector (make_number (length_in_elts + 1), Qnil);
2248
2249 /* No Lisp_Object to trace in there. */
2250 XSETPVECTYPESIZE (XVECTOR (val), PVEC_BOOL_VECTOR, 0);
2251
2252 p = XBOOL_VECTOR (val);
2253 p->size = XFASTINT (length);
2254
2255 real_init = (NILP (init) ? 0 : -1);
2256 for (i = 0; i < length_in_chars ; i++)
2257 p->data[i] = real_init;
2258
2259 /* Clear the extraneous bits in the last byte. */
2260 if (XINT (length) != length_in_chars * BOOL_VECTOR_BITS_PER_CHAR)
2261 p->data[length_in_chars - 1]
2262 &= (1 << (XINT (length) % BOOL_VECTOR_BITS_PER_CHAR)) - 1;
2263
2264 return val;
2265 }
2266
2267
2268 /* Make a string from NBYTES bytes at CONTENTS, and compute the number
2269 of characters from the contents. This string may be unibyte or
2270 multibyte, depending on the contents. */
2271
2272 Lisp_Object
2273 make_string (const char *contents, EMACS_INT nbytes)
2274 {
2275 register Lisp_Object val;
2276 EMACS_INT nchars, multibyte_nbytes;
2277
2278 parse_str_as_multibyte ((const unsigned char *) contents, nbytes,
2279 &nchars, &multibyte_nbytes);
2280 if (nbytes == nchars || nbytes != multibyte_nbytes)
2281 /* CONTENTS contains no multibyte sequences or contains an invalid
2282 multibyte sequence. We must make unibyte string. */
2283 val = make_unibyte_string (contents, nbytes);
2284 else
2285 val = make_multibyte_string (contents, nchars, nbytes);
2286 return val;
2287 }
2288
2289
2290 /* Make an unibyte string from LENGTH bytes at CONTENTS. */
2291
2292 Lisp_Object
2293 make_unibyte_string (const char *contents, EMACS_INT length)
2294 {
2295 register Lisp_Object val;
2296 val = make_uninit_string (length);
2297 memcpy (SDATA (val), contents, length);
2298 return val;
2299 }
2300
2301
2302 /* Make a multibyte string from NCHARS characters occupying NBYTES
2303 bytes at CONTENTS. */
2304
2305 Lisp_Object
2306 make_multibyte_string (const char *contents,
2307 EMACS_INT nchars, EMACS_INT nbytes)
2308 {
2309 register Lisp_Object val;
2310 val = make_uninit_multibyte_string (nchars, nbytes);
2311 memcpy (SDATA (val), contents, nbytes);
2312 return val;
2313 }
2314
2315
2316 /* Make a string from NCHARS characters occupying NBYTES bytes at
2317 CONTENTS. It is a multibyte string if NBYTES != NCHARS. */
2318
2319 Lisp_Object
2320 make_string_from_bytes (const char *contents,
2321 EMACS_INT nchars, EMACS_INT nbytes)
2322 {
2323 register Lisp_Object val;
2324 val = make_uninit_multibyte_string (nchars, nbytes);
2325 memcpy (SDATA (val), contents, nbytes);
2326 if (SBYTES (val) == SCHARS (val))
2327 STRING_SET_UNIBYTE (val);
2328 return val;
2329 }
2330
2331
2332 /* Make a string from NCHARS characters occupying NBYTES bytes at
2333 CONTENTS. The argument MULTIBYTE controls whether to label the
2334 string as multibyte. If NCHARS is negative, it counts the number of
2335 characters by itself. */
2336
2337 Lisp_Object
2338 make_specified_string (const char *contents,
2339 EMACS_INT nchars, EMACS_INT nbytes, int multibyte)
2340 {
2341 register Lisp_Object val;
2342
2343 if (nchars < 0)
2344 {
2345 if (multibyte)
2346 nchars = multibyte_chars_in_text ((const unsigned char *) contents,
2347 nbytes);
2348 else
2349 nchars = nbytes;
2350 }
2351 val = make_uninit_multibyte_string (nchars, nbytes);
2352 memcpy (SDATA (val), contents, nbytes);
2353 if (!multibyte)
2354 STRING_SET_UNIBYTE (val);
2355 return val;
2356 }
2357
2358
2359 /* Make a string from the data at STR, treating it as multibyte if the
2360 data warrants. */
2361
2362 Lisp_Object
2363 build_string (const char *str)
2364 {
2365 return make_string (str, strlen (str));
2366 }
2367
2368
2369 /* Return an unibyte Lisp_String set up to hold LENGTH characters
2370 occupying LENGTH bytes. */
2371
2372 Lisp_Object
2373 make_uninit_string (EMACS_INT length)
2374 {
2375 Lisp_Object val;
2376
2377 if (!length)
2378 return empty_unibyte_string;
2379 val = make_uninit_multibyte_string (length, length);
2380 STRING_SET_UNIBYTE (val);
2381 return val;
2382 }
2383
2384
2385 /* Return a multibyte Lisp_String set up to hold NCHARS characters
2386 which occupy NBYTES bytes. */
2387
2388 Lisp_Object
2389 make_uninit_multibyte_string (EMACS_INT nchars, EMACS_INT nbytes)
2390 {
2391 Lisp_Object string;
2392 struct Lisp_String *s;
2393
2394 if (nchars < 0)
2395 abort ();
2396 if (!nbytes)
2397 return empty_multibyte_string;
2398
2399 s = allocate_string ();
2400 allocate_string_data (s, nchars, nbytes);
2401 XSETSTRING (string, s);
2402 string_chars_consed += nbytes;
2403 return string;
2404 }
2405
2406
2407 \f
2408 /***********************************************************************
2409 Float Allocation
2410 ***********************************************************************/
2411
2412 /* We store float cells inside of float_blocks, allocating a new
2413 float_block with malloc whenever necessary. Float cells reclaimed
2414 by GC are put on a free list to be reallocated before allocating
2415 any new float cells from the latest float_block. */
2416
2417 #define FLOAT_BLOCK_SIZE \
2418 (((BLOCK_BYTES - sizeof (struct float_block *) \
2419 /* The compiler might add padding at the end. */ \
2420 - (sizeof (struct Lisp_Float) - sizeof (int))) * CHAR_BIT) \
2421 / (sizeof (struct Lisp_Float) * CHAR_BIT + 1))
2422
2423 #define GETMARKBIT(block,n) \
2424 (((block)->gcmarkbits[(n) / (sizeof(int) * CHAR_BIT)] \
2425 >> ((n) % (sizeof(int) * CHAR_BIT))) \
2426 & 1)
2427
2428 #define SETMARKBIT(block,n) \
2429 (block)->gcmarkbits[(n) / (sizeof(int) * CHAR_BIT)] \
2430 |= 1 << ((n) % (sizeof(int) * CHAR_BIT))
2431
2432 #define UNSETMARKBIT(block,n) \
2433 (block)->gcmarkbits[(n) / (sizeof(int) * CHAR_BIT)] \
2434 &= ~(1 << ((n) % (sizeof(int) * CHAR_BIT)))
2435
2436 #define FLOAT_BLOCK(fptr) \
2437 ((struct float_block *) (((uintptr_t) (fptr)) & ~(BLOCK_ALIGN - 1)))
2438
2439 #define FLOAT_INDEX(fptr) \
2440 ((((uintptr_t) (fptr)) & (BLOCK_ALIGN - 1)) / sizeof (struct Lisp_Float))
2441
2442 struct float_block
2443 {
2444 /* Place `floats' at the beginning, to ease up FLOAT_INDEX's job. */
2445 struct Lisp_Float floats[FLOAT_BLOCK_SIZE];
2446 int gcmarkbits[1 + FLOAT_BLOCK_SIZE / (sizeof(int) * CHAR_BIT)];
2447 struct float_block *next;
2448 };
2449
2450 #define FLOAT_MARKED_P(fptr) \
2451 GETMARKBIT (FLOAT_BLOCK (fptr), FLOAT_INDEX ((fptr)))
2452
2453 #define FLOAT_MARK(fptr) \
2454 SETMARKBIT (FLOAT_BLOCK (fptr), FLOAT_INDEX ((fptr)))
2455
2456 #define FLOAT_UNMARK(fptr) \
2457 UNSETMARKBIT (FLOAT_BLOCK (fptr), FLOAT_INDEX ((fptr)))
2458
2459 /* Current float_block. */
2460
2461 static struct float_block *float_block;
2462
2463 /* Index of first unused Lisp_Float in the current float_block. */
2464
2465 static int float_block_index;
2466
2467 /* Total number of float blocks now in use. */
2468
2469 static int n_float_blocks;
2470
2471 /* Free-list of Lisp_Floats. */
2472
2473 static struct Lisp_Float *float_free_list;
2474
2475
2476 /* Initialize float allocation. */
2477
2478 static void
2479 init_float (void)
2480 {
2481 float_block = NULL;
2482 float_block_index = FLOAT_BLOCK_SIZE; /* Force alloc of new float_block. */
2483 float_free_list = 0;
2484 n_float_blocks = 0;
2485 }
2486
2487
2488 /* Return a new float object with value FLOAT_VALUE. */
2489
2490 Lisp_Object
2491 make_float (double float_value)
2492 {
2493 register Lisp_Object val;
2494
2495 /* eassert (!handling_signal); */
2496
2497 MALLOC_BLOCK_INPUT;
2498
2499 if (float_free_list)
2500 {
2501 /* We use the data field for chaining the free list
2502 so that we won't use the same field that has the mark bit. */
2503 XSETFLOAT (val, float_free_list);
2504 float_free_list = float_free_list->u.chain;
2505 }
2506 else
2507 {
2508 if (float_block_index == FLOAT_BLOCK_SIZE)
2509 {
2510 register struct float_block *new;
2511
2512 new = (struct float_block *) lisp_align_malloc (sizeof *new,
2513 MEM_TYPE_FLOAT);
2514 new->next = float_block;
2515 memset (new->gcmarkbits, 0, sizeof new->gcmarkbits);
2516 float_block = new;
2517 float_block_index = 0;
2518 n_float_blocks++;
2519 }
2520 XSETFLOAT (val, &float_block->floats[float_block_index]);
2521 float_block_index++;
2522 }
2523
2524 MALLOC_UNBLOCK_INPUT;
2525
2526 XFLOAT_INIT (val, float_value);
2527 eassert (!FLOAT_MARKED_P (XFLOAT (val)));
2528 consing_since_gc += sizeof (struct Lisp_Float);
2529 floats_consed++;
2530 return val;
2531 }
2532
2533
2534 \f
2535 /***********************************************************************
2536 Cons Allocation
2537 ***********************************************************************/
2538
2539 /* We store cons cells inside of cons_blocks, allocating a new
2540 cons_block with malloc whenever necessary. Cons cells reclaimed by
2541 GC are put on a free list to be reallocated before allocating
2542 any new cons cells from the latest cons_block. */
2543
2544 #define CONS_BLOCK_SIZE \
2545 (((BLOCK_BYTES - sizeof (struct cons_block *)) * CHAR_BIT) \
2546 / (sizeof (struct Lisp_Cons) * CHAR_BIT + 1))
2547
2548 #define CONS_BLOCK(fptr) \
2549 ((struct cons_block *) ((uintptr_t) (fptr) & ~(BLOCK_ALIGN - 1)))
2550
2551 #define CONS_INDEX(fptr) \
2552 (((uintptr_t) (fptr) & (BLOCK_ALIGN - 1)) / sizeof (struct Lisp_Cons))
2553
2554 struct cons_block
2555 {
2556 /* Place `conses' at the beginning, to ease up CONS_INDEX's job. */
2557 struct Lisp_Cons conses[CONS_BLOCK_SIZE];
2558 int gcmarkbits[1 + CONS_BLOCK_SIZE / (sizeof(int) * CHAR_BIT)];
2559 struct cons_block *next;
2560 };
2561
2562 #define CONS_MARKED_P(fptr) \
2563 GETMARKBIT (CONS_BLOCK (fptr), CONS_INDEX ((fptr)))
2564
2565 #define CONS_MARK(fptr) \
2566 SETMARKBIT (CONS_BLOCK (fptr), CONS_INDEX ((fptr)))
2567
2568 #define CONS_UNMARK(fptr) \
2569 UNSETMARKBIT (CONS_BLOCK (fptr), CONS_INDEX ((fptr)))
2570
2571 /* Current cons_block. */
2572
2573 static struct cons_block *cons_block;
2574
2575 /* Index of first unused Lisp_Cons in the current block. */
2576
2577 static int cons_block_index;
2578
2579 /* Free-list of Lisp_Cons structures. */
2580
2581 static struct Lisp_Cons *cons_free_list;
2582
2583 /* Total number of cons blocks now in use. */
2584
2585 static int n_cons_blocks;
2586
2587
2588 /* Initialize cons allocation. */
2589
2590 static void
2591 init_cons (void)
2592 {
2593 cons_block = NULL;
2594 cons_block_index = CONS_BLOCK_SIZE; /* Force alloc of new cons_block. */
2595 cons_free_list = 0;
2596 n_cons_blocks = 0;
2597 }
2598
2599
2600 /* Explicitly free a cons cell by putting it on the free-list. */
2601
2602 void
2603 free_cons (struct Lisp_Cons *ptr)
2604 {
2605 ptr->u.chain = cons_free_list;
2606 #if GC_MARK_STACK
2607 ptr->car = Vdead;
2608 #endif
2609 cons_free_list = ptr;
2610 }
2611
2612 DEFUN ("cons", Fcons, Scons, 2, 2, 0,
2613 doc: /* Create a new cons, give it CAR and CDR as components, and return it. */)
2614 (Lisp_Object car, Lisp_Object cdr)
2615 {
2616 register Lisp_Object val;
2617
2618 /* eassert (!handling_signal); */
2619
2620 MALLOC_BLOCK_INPUT;
2621
2622 if (cons_free_list)
2623 {
2624 /* We use the cdr for chaining the free list
2625 so that we won't use the same field that has the mark bit. */
2626 XSETCONS (val, cons_free_list);
2627 cons_free_list = cons_free_list->u.chain;
2628 }
2629 else
2630 {
2631 if (cons_block_index == CONS_BLOCK_SIZE)
2632 {
2633 register struct cons_block *new;
2634 new = (struct cons_block *) lisp_align_malloc (sizeof *new,
2635 MEM_TYPE_CONS);
2636 memset (new->gcmarkbits, 0, sizeof new->gcmarkbits);
2637 new->next = cons_block;
2638 cons_block = new;
2639 cons_block_index = 0;
2640 n_cons_blocks++;
2641 }
2642 XSETCONS (val, &cons_block->conses[cons_block_index]);
2643 cons_block_index++;
2644 }
2645
2646 MALLOC_UNBLOCK_INPUT;
2647
2648 XSETCAR (val, car);
2649 XSETCDR (val, cdr);
2650 eassert (!CONS_MARKED_P (XCONS (val)));
2651 consing_since_gc += sizeof (struct Lisp_Cons);
2652 cons_cells_consed++;
2653 return val;
2654 }
2655
2656 #ifdef GC_CHECK_CONS_LIST
2657 /* Get an error now if there's any junk in the cons free list. */
2658 void
2659 check_cons_list (void)
2660 {
2661 struct Lisp_Cons *tail = cons_free_list;
2662
2663 while (tail)
2664 tail = tail->u.chain;
2665 }
2666 #endif
2667
2668 /* Make a list of 1, 2, 3, 4 or 5 specified objects. */
2669
2670 Lisp_Object
2671 list1 (Lisp_Object arg1)
2672 {
2673 return Fcons (arg1, Qnil);
2674 }
2675
2676 Lisp_Object
2677 list2 (Lisp_Object arg1, Lisp_Object arg2)
2678 {
2679 return Fcons (arg1, Fcons (arg2, Qnil));
2680 }
2681
2682
2683 Lisp_Object
2684 list3 (Lisp_Object arg1, Lisp_Object arg2, Lisp_Object arg3)
2685 {
2686 return Fcons (arg1, Fcons (arg2, Fcons (arg3, Qnil)));
2687 }
2688
2689
2690 Lisp_Object
2691 list4 (Lisp_Object arg1, Lisp_Object arg2, Lisp_Object arg3, Lisp_Object arg4)
2692 {
2693 return Fcons (arg1, Fcons (arg2, Fcons (arg3, Fcons (arg4, Qnil))));
2694 }
2695
2696
2697 Lisp_Object
2698 list5 (Lisp_Object arg1, Lisp_Object arg2, Lisp_Object arg3, Lisp_Object arg4, Lisp_Object arg5)
2699 {
2700 return Fcons (arg1, Fcons (arg2, Fcons (arg3, Fcons (arg4,
2701 Fcons (arg5, Qnil)))));
2702 }
2703
2704
2705 DEFUN ("list", Flist, Slist, 0, MANY, 0,
2706 doc: /* Return a newly created list with specified arguments as elements.
2707 Any number of arguments, even zero arguments, are allowed.
2708 usage: (list &rest OBJECTS) */)
2709 (size_t nargs, register Lisp_Object *args)
2710 {
2711 register Lisp_Object val;
2712 val = Qnil;
2713
2714 while (nargs > 0)
2715 {
2716 nargs--;
2717 val = Fcons (args[nargs], val);
2718 }
2719 return val;
2720 }
2721
2722
2723 DEFUN ("make-list", Fmake_list, Smake_list, 2, 2, 0,
2724 doc: /* Return a newly created list of length LENGTH, with each element being INIT. */)
2725 (register Lisp_Object length, Lisp_Object init)
2726 {
2727 register Lisp_Object val;
2728 register EMACS_INT size;
2729
2730 CHECK_NATNUM (length);
2731 size = XFASTINT (length);
2732
2733 val = Qnil;
2734 while (size > 0)
2735 {
2736 val = Fcons (init, val);
2737 --size;
2738
2739 if (size > 0)
2740 {
2741 val = Fcons (init, val);
2742 --size;
2743
2744 if (size > 0)
2745 {
2746 val = Fcons (init, val);
2747 --size;
2748
2749 if (size > 0)
2750 {
2751 val = Fcons (init, val);
2752 --size;
2753
2754 if (size > 0)
2755 {
2756 val = Fcons (init, val);
2757 --size;
2758 }
2759 }
2760 }
2761 }
2762
2763 QUIT;
2764 }
2765
2766 return val;
2767 }
2768
2769
2770 \f
2771 /***********************************************************************
2772 Vector Allocation
2773 ***********************************************************************/
2774
2775 /* Singly-linked list of all vectors. */
2776
2777 static struct Lisp_Vector *all_vectors;
2778
2779 /* Total number of vector-like objects now in use. */
2780
2781 static int n_vectors;
2782
2783
2784 /* Value is a pointer to a newly allocated Lisp_Vector structure
2785 with room for LEN Lisp_Objects. */
2786
2787 static struct Lisp_Vector *
2788 allocate_vectorlike (EMACS_INT len)
2789 {
2790 struct Lisp_Vector *p;
2791 size_t nbytes;
2792 int header_size = offsetof (struct Lisp_Vector, contents);
2793 int word_size = sizeof p->contents[0];
2794
2795 if ((SIZE_MAX - header_size) / word_size < len)
2796 memory_full (SIZE_MAX);
2797
2798 MALLOC_BLOCK_INPUT;
2799
2800 #ifdef DOUG_LEA_MALLOC
2801 /* Prevent mmap'ing the chunk. Lisp data may not be mmap'ed
2802 because mapped region contents are not preserved in
2803 a dumped Emacs. */
2804 mallopt (M_MMAP_MAX, 0);
2805 #endif
2806
2807 /* This gets triggered by code which I haven't bothered to fix. --Stef */
2808 /* eassert (!handling_signal); */
2809
2810 nbytes = header_size + len * word_size;
2811 p = (struct Lisp_Vector *) lisp_malloc (nbytes, MEM_TYPE_VECTORLIKE);
2812
2813 #ifdef DOUG_LEA_MALLOC
2814 /* Back to a reasonable maximum of mmap'ed areas. */
2815 mallopt (M_MMAP_MAX, MMAP_MAX_AREAS);
2816 #endif
2817
2818 consing_since_gc += nbytes;
2819 vector_cells_consed += len;
2820
2821 p->header.next.vector = all_vectors;
2822 all_vectors = p;
2823
2824 MALLOC_UNBLOCK_INPUT;
2825
2826 ++n_vectors;
2827 return p;
2828 }
2829
2830
2831 /* Allocate a vector with NSLOTS slots. */
2832
2833 struct Lisp_Vector *
2834 allocate_vector (EMACS_INT nslots)
2835 {
2836 struct Lisp_Vector *v = allocate_vectorlike (nslots);
2837 v->header.size = nslots;
2838 return v;
2839 }
2840
2841
2842 /* Allocate other vector-like structures. */
2843
2844 struct Lisp_Vector *
2845 allocate_pseudovector (int memlen, int lisplen, EMACS_INT tag)
2846 {
2847 struct Lisp_Vector *v = allocate_vectorlike (memlen);
2848 EMACS_INT i;
2849
2850 /* Only the first lisplen slots will be traced normally by the GC. */
2851 for (i = 0; i < lisplen; ++i)
2852 v->contents[i] = Qnil;
2853
2854 XSETPVECTYPESIZE (v, tag, lisplen);
2855 return v;
2856 }
2857
2858 struct Lisp_Hash_Table *
2859 allocate_hash_table (void)
2860 {
2861 return ALLOCATE_PSEUDOVECTOR (struct Lisp_Hash_Table, count, PVEC_HASH_TABLE);
2862 }
2863
2864
2865 struct window *
2866 allocate_window (void)
2867 {
2868 return ALLOCATE_PSEUDOVECTOR(struct window, current_matrix, PVEC_WINDOW);
2869 }
2870
2871
2872 struct terminal *
2873 allocate_terminal (void)
2874 {
2875 struct terminal *t = ALLOCATE_PSEUDOVECTOR (struct terminal,
2876 next_terminal, PVEC_TERMINAL);
2877 /* Zero out the non-GC'd fields. FIXME: This should be made unnecessary. */
2878 memset (&t->next_terminal, 0,
2879 (char*) (t + 1) - (char*) &t->next_terminal);
2880
2881 return t;
2882 }
2883
2884 struct frame *
2885 allocate_frame (void)
2886 {
2887 struct frame *f = ALLOCATE_PSEUDOVECTOR (struct frame,
2888 face_cache, PVEC_FRAME);
2889 /* Zero out the non-GC'd fields. FIXME: This should be made unnecessary. */
2890 memset (&f->face_cache, 0,
2891 (char *) (f + 1) - (char *) &f->face_cache);
2892 return f;
2893 }
2894
2895
2896 struct Lisp_Process *
2897 allocate_process (void)
2898 {
2899 return ALLOCATE_PSEUDOVECTOR (struct Lisp_Process, pid, PVEC_PROCESS);
2900 }
2901
2902
2903 DEFUN ("make-vector", Fmake_vector, Smake_vector, 2, 2, 0,
2904 doc: /* Return a newly created vector of length LENGTH, with each element being INIT.
2905 See also the function `vector'. */)
2906 (register Lisp_Object length, Lisp_Object init)
2907 {
2908 Lisp_Object vector;
2909 register EMACS_INT sizei;
2910 register EMACS_INT i;
2911 register struct Lisp_Vector *p;
2912
2913 CHECK_NATNUM (length);
2914 sizei = XFASTINT (length);
2915
2916 p = allocate_vector (sizei);
2917 for (i = 0; i < sizei; i++)
2918 p->contents[i] = init;
2919
2920 XSETVECTOR (vector, p);
2921 return vector;
2922 }
2923
2924
2925 DEFUN ("vector", Fvector, Svector, 0, MANY, 0,
2926 doc: /* Return a newly created vector with specified arguments as elements.
2927 Any number of arguments, even zero arguments, are allowed.
2928 usage: (vector &rest OBJECTS) */)
2929 (register size_t nargs, Lisp_Object *args)
2930 {
2931 register Lisp_Object len, val;
2932 register size_t i;
2933 register struct Lisp_Vector *p;
2934
2935 XSETFASTINT (len, nargs);
2936 val = Fmake_vector (len, Qnil);
2937 p = XVECTOR (val);
2938 for (i = 0; i < nargs; i++)
2939 p->contents[i] = args[i];
2940 return val;
2941 }
2942
2943
2944 DEFUN ("make-byte-code", Fmake_byte_code, Smake_byte_code, 4, MANY, 0,
2945 doc: /* Create a byte-code object with specified arguments as elements.
2946 The arguments should be the ARGLIST, bytecode-string BYTE-CODE, constant
2947 vector CONSTANTS, maximum stack size DEPTH, (optional) DOCSTRING,
2948 and (optional) INTERACTIVE-SPEC.
2949 The first four arguments are required; at most six have any
2950 significance.
2951 The ARGLIST can be either like the one of `lambda', in which case the arguments
2952 will be dynamically bound before executing the byte code, or it can be an
2953 integer of the form NNNNNNNRMMMMMMM where the 7bit MMMMMMM specifies the
2954 minimum number of arguments, the 7-bit NNNNNNN specifies the maximum number
2955 of arguments (ignoring &rest) and the R bit specifies whether there is a &rest
2956 argument to catch the left-over arguments. If such an integer is used, the
2957 arguments will not be dynamically bound but will be instead pushed on the
2958 stack before executing the byte-code.
2959 usage: (make-byte-code ARGLIST BYTE-CODE CONSTANTS DEPTH &optional DOCSTRING INTERACTIVE-SPEC &rest ELEMENTS) */)
2960 (register size_t nargs, Lisp_Object *args)
2961 {
2962 register Lisp_Object len, val;
2963 register size_t i;
2964 register struct Lisp_Vector *p;
2965
2966 XSETFASTINT (len, nargs);
2967 if (!NILP (Vpurify_flag))
2968 val = make_pure_vector ((EMACS_INT) nargs);
2969 else
2970 val = Fmake_vector (len, Qnil);
2971
2972 if (nargs > 1 && STRINGP (args[1]) && STRING_MULTIBYTE (args[1]))
2973 /* BYTECODE-STRING must have been produced by Emacs 20.2 or the
2974 earlier because they produced a raw 8-bit string for byte-code
2975 and now such a byte-code string is loaded as multibyte while
2976 raw 8-bit characters converted to multibyte form. Thus, now we
2977 must convert them back to the original unibyte form. */
2978 args[1] = Fstring_as_unibyte (args[1]);
2979
2980 p = XVECTOR (val);
2981 for (i = 0; i < nargs; i++)
2982 {
2983 if (!NILP (Vpurify_flag))
2984 args[i] = Fpurecopy (args[i]);
2985 p->contents[i] = args[i];
2986 }
2987 XSETPVECTYPE (p, PVEC_COMPILED);
2988 XSETCOMPILED (val, p);
2989 return val;
2990 }
2991
2992
2993 \f
2994 /***********************************************************************
2995 Symbol Allocation
2996 ***********************************************************************/
2997
2998 /* Each symbol_block is just under 1020 bytes long, since malloc
2999 really allocates in units of powers of two and uses 4 bytes for its
3000 own overhead. */
3001
3002 #define SYMBOL_BLOCK_SIZE \
3003 ((1020 - sizeof (struct symbol_block *)) / sizeof (struct Lisp_Symbol))
3004
3005 struct symbol_block
3006 {
3007 /* Place `symbols' first, to preserve alignment. */
3008 struct Lisp_Symbol symbols[SYMBOL_BLOCK_SIZE];
3009 struct symbol_block *next;
3010 };
3011
3012 /* Current symbol block and index of first unused Lisp_Symbol
3013 structure in it. */
3014
3015 static struct symbol_block *symbol_block;
3016 static int symbol_block_index;
3017
3018 /* List of free symbols. */
3019
3020 static struct Lisp_Symbol *symbol_free_list;
3021
3022 /* Total number of symbol blocks now in use. */
3023
3024 static int n_symbol_blocks;
3025
3026
3027 /* Initialize symbol allocation. */
3028
3029 static void
3030 init_symbol (void)
3031 {
3032 symbol_block = NULL;
3033 symbol_block_index = SYMBOL_BLOCK_SIZE;
3034 symbol_free_list = 0;
3035 n_symbol_blocks = 0;
3036 }
3037
3038
3039 DEFUN ("make-symbol", Fmake_symbol, Smake_symbol, 1, 1, 0,
3040 doc: /* Return a newly allocated uninterned symbol whose name is NAME.
3041 Its value and function definition are void, and its property list is nil. */)
3042 (Lisp_Object name)
3043 {
3044 register Lisp_Object val;
3045 register struct Lisp_Symbol *p;
3046
3047 CHECK_STRING (name);
3048
3049 /* eassert (!handling_signal); */
3050
3051 MALLOC_BLOCK_INPUT;
3052
3053 if (symbol_free_list)
3054 {
3055 XSETSYMBOL (val, symbol_free_list);
3056 symbol_free_list = symbol_free_list->next;
3057 }
3058 else
3059 {
3060 if (symbol_block_index == SYMBOL_BLOCK_SIZE)
3061 {
3062 struct symbol_block *new;
3063 new = (struct symbol_block *) lisp_malloc (sizeof *new,
3064 MEM_TYPE_SYMBOL);
3065 new->next = symbol_block;
3066 symbol_block = new;
3067 symbol_block_index = 0;
3068 n_symbol_blocks++;
3069 }
3070 XSETSYMBOL (val, &symbol_block->symbols[symbol_block_index]);
3071 symbol_block_index++;
3072 }
3073
3074 MALLOC_UNBLOCK_INPUT;
3075
3076 p = XSYMBOL (val);
3077 p->xname = name;
3078 p->plist = Qnil;
3079 p->redirect = SYMBOL_PLAINVAL;
3080 SET_SYMBOL_VAL (p, Qunbound);
3081 p->function = Qunbound;
3082 p->next = NULL;
3083 p->gcmarkbit = 0;
3084 p->interned = SYMBOL_UNINTERNED;
3085 p->constant = 0;
3086 p->declared_special = 0;
3087 consing_since_gc += sizeof (struct Lisp_Symbol);
3088 symbols_consed++;
3089 return val;
3090 }
3091
3092
3093 \f
3094 /***********************************************************************
3095 Marker (Misc) Allocation
3096 ***********************************************************************/
3097
3098 /* Allocation of markers and other objects that share that structure.
3099 Works like allocation of conses. */
3100
3101 #define MARKER_BLOCK_SIZE \
3102 ((1020 - sizeof (struct marker_block *)) / sizeof (union Lisp_Misc))
3103
3104 struct marker_block
3105 {
3106 /* Place `markers' first, to preserve alignment. */
3107 union Lisp_Misc markers[MARKER_BLOCK_SIZE];
3108 struct marker_block *next;
3109 };
3110
3111 static struct marker_block *marker_block;
3112 static int marker_block_index;
3113
3114 static union Lisp_Misc *marker_free_list;
3115
3116 /* Total number of marker blocks now in use. */
3117
3118 static int n_marker_blocks;
3119
3120 static void
3121 init_marker (void)
3122 {
3123 marker_block = NULL;
3124 marker_block_index = MARKER_BLOCK_SIZE;
3125 marker_free_list = 0;
3126 n_marker_blocks = 0;
3127 }
3128
3129 /* Return a newly allocated Lisp_Misc object, with no substructure. */
3130
3131 Lisp_Object
3132 allocate_misc (void)
3133 {
3134 Lisp_Object val;
3135
3136 /* eassert (!handling_signal); */
3137
3138 MALLOC_BLOCK_INPUT;
3139
3140 if (marker_free_list)
3141 {
3142 XSETMISC (val, marker_free_list);
3143 marker_free_list = marker_free_list->u_free.chain;
3144 }
3145 else
3146 {
3147 if (marker_block_index == MARKER_BLOCK_SIZE)
3148 {
3149 struct marker_block *new;
3150 new = (struct marker_block *) lisp_malloc (sizeof *new,
3151 MEM_TYPE_MISC);
3152 new->next = marker_block;
3153 marker_block = new;
3154 marker_block_index = 0;
3155 n_marker_blocks++;
3156 total_free_markers += MARKER_BLOCK_SIZE;
3157 }
3158 XSETMISC (val, &marker_block->markers[marker_block_index]);
3159 marker_block_index++;
3160 }
3161
3162 MALLOC_UNBLOCK_INPUT;
3163
3164 --total_free_markers;
3165 consing_since_gc += sizeof (union Lisp_Misc);
3166 misc_objects_consed++;
3167 XMISCANY (val)->gcmarkbit = 0;
3168 return val;
3169 }
3170
3171 /* Free a Lisp_Misc object */
3172
3173 static void
3174 free_misc (Lisp_Object misc)
3175 {
3176 XMISCTYPE (misc) = Lisp_Misc_Free;
3177 XMISC (misc)->u_free.chain = marker_free_list;
3178 marker_free_list = XMISC (misc);
3179
3180 total_free_markers++;
3181 }
3182
3183 /* Return a Lisp_Misc_Save_Value object containing POINTER and
3184 INTEGER. This is used to package C values to call record_unwind_protect.
3185 The unwind function can get the C values back using XSAVE_VALUE. */
3186
3187 Lisp_Object
3188 make_save_value (void *pointer, int integer)
3189 {
3190 register Lisp_Object val;
3191 register struct Lisp_Save_Value *p;
3192
3193 val = allocate_misc ();
3194 XMISCTYPE (val) = Lisp_Misc_Save_Value;
3195 p = XSAVE_VALUE (val);
3196 p->pointer = pointer;
3197 p->integer = integer;
3198 p->dogc = 0;
3199 return val;
3200 }
3201
3202 DEFUN ("make-marker", Fmake_marker, Smake_marker, 0, 0, 0,
3203 doc: /* Return a newly allocated marker which does not point at any place. */)
3204 (void)
3205 {
3206 register Lisp_Object val;
3207 register struct Lisp_Marker *p;
3208
3209 val = allocate_misc ();
3210 XMISCTYPE (val) = Lisp_Misc_Marker;
3211 p = XMARKER (val);
3212 p->buffer = 0;
3213 p->bytepos = 0;
3214 p->charpos = 0;
3215 p->next = NULL;
3216 p->insertion_type = 0;
3217 return val;
3218 }
3219
3220 /* Put MARKER back on the free list after using it temporarily. */
3221
3222 void
3223 free_marker (Lisp_Object marker)
3224 {
3225 unchain_marker (XMARKER (marker));
3226 free_misc (marker);
3227 }
3228
3229 \f
3230 /* Return a newly created vector or string with specified arguments as
3231 elements. If all the arguments are characters that can fit
3232 in a string of events, make a string; otherwise, make a vector.
3233
3234 Any number of arguments, even zero arguments, are allowed. */
3235
3236 Lisp_Object
3237 make_event_array (register int nargs, Lisp_Object *args)
3238 {
3239 int i;
3240
3241 for (i = 0; i < nargs; i++)
3242 /* The things that fit in a string
3243 are characters that are in 0...127,
3244 after discarding the meta bit and all the bits above it. */
3245 if (!INTEGERP (args[i])
3246 || (XINT (args[i]) & ~(-CHAR_META)) >= 0200)
3247 return Fvector (nargs, args);
3248
3249 /* Since the loop exited, we know that all the things in it are
3250 characters, so we can make a string. */
3251 {
3252 Lisp_Object result;
3253
3254 result = Fmake_string (make_number (nargs), make_number (0));
3255 for (i = 0; i < nargs; i++)
3256 {
3257 SSET (result, i, XINT (args[i]));
3258 /* Move the meta bit to the right place for a string char. */
3259 if (XINT (args[i]) & CHAR_META)
3260 SSET (result, i, SREF (result, i) | 0x80);
3261 }
3262
3263 return result;
3264 }
3265 }
3266
3267
3268 \f
3269 /************************************************************************
3270 Memory Full Handling
3271 ************************************************************************/
3272
3273
3274 /* Called if malloc (NBYTES) returns zero. If NBYTES == SIZE_MAX,
3275 there may have been size_t overflow so that malloc was never
3276 called, or perhaps malloc was invoked successfully but the
3277 resulting pointer had problems fitting into a tagged EMACS_INT. In
3278 either case this counts as memory being full even though malloc did
3279 not fail. */
3280
3281 void
3282 memory_full (size_t nbytes)
3283 {
3284 /* Do not go into hysterics merely because a large request failed. */
3285 int enough_free_memory = 0;
3286 if (SPARE_MEMORY < nbytes)
3287 {
3288 void *p = malloc (SPARE_MEMORY);
3289 if (p)
3290 {
3291 if (spare_memory[0])
3292 free (p);
3293 else
3294 spare_memory[0] = p;
3295 enough_free_memory = 1;
3296 }
3297 }
3298
3299 if (! enough_free_memory)
3300 {
3301 int i;
3302
3303 Vmemory_full = Qt;
3304
3305 memory_full_cons_threshold = sizeof (struct cons_block);
3306
3307 /* The first time we get here, free the spare memory. */
3308 for (i = 0; i < sizeof (spare_memory) / sizeof (char *); i++)
3309 if (spare_memory[i])
3310 {
3311 if (i == 0)
3312 free (spare_memory[i]);
3313 else if (i >= 1 && i <= 4)
3314 lisp_align_free (spare_memory[i]);
3315 else
3316 lisp_free (spare_memory[i]);
3317 spare_memory[i] = 0;
3318 }
3319
3320 /* Record the space now used. When it decreases substantially,
3321 we can refill the memory reserve. */
3322 #if !defined SYSTEM_MALLOC && !defined SYNC_INPUT
3323 bytes_used_when_full = BYTES_USED;
3324 #endif
3325 }
3326
3327 /* This used to call error, but if we've run out of memory, we could
3328 get infinite recursion trying to build the string. */
3329 xsignal (Qnil, Vmemory_signal_data);
3330 }
3331
3332 /* If we released our reserve (due to running out of memory),
3333 and we have a fair amount free once again,
3334 try to set aside another reserve in case we run out once more.
3335
3336 This is called when a relocatable block is freed in ralloc.c,
3337 and also directly from this file, in case we're not using ralloc.c. */
3338
3339 void
3340 refill_memory_reserve (void)
3341 {
3342 #ifndef SYSTEM_MALLOC
3343 if (spare_memory[0] == 0)
3344 spare_memory[0] = (char *) malloc ((size_t) SPARE_MEMORY);
3345 if (spare_memory[1] == 0)
3346 spare_memory[1] = (char *) lisp_align_malloc (sizeof (struct cons_block),
3347 MEM_TYPE_CONS);
3348 if (spare_memory[2] == 0)
3349 spare_memory[2] = (char *) lisp_align_malloc (sizeof (struct cons_block),
3350 MEM_TYPE_CONS);
3351 if (spare_memory[3] == 0)
3352 spare_memory[3] = (char *) lisp_align_malloc (sizeof (struct cons_block),
3353 MEM_TYPE_CONS);
3354 if (spare_memory[4] == 0)
3355 spare_memory[4] = (char *) lisp_align_malloc (sizeof (struct cons_block),
3356 MEM_TYPE_CONS);
3357 if (spare_memory[5] == 0)
3358 spare_memory[5] = (char *) lisp_malloc (sizeof (struct string_block),
3359 MEM_TYPE_STRING);
3360 if (spare_memory[6] == 0)
3361 spare_memory[6] = (char *) lisp_malloc (sizeof (struct string_block),
3362 MEM_TYPE_STRING);
3363 if (spare_memory[0] && spare_memory[1] && spare_memory[5])
3364 Vmemory_full = Qnil;
3365 #endif
3366 }
3367 \f
3368 /************************************************************************
3369 C Stack Marking
3370 ************************************************************************/
3371
3372 #if GC_MARK_STACK || defined GC_MALLOC_CHECK
3373
3374 /* Conservative C stack marking requires a method to identify possibly
3375 live Lisp objects given a pointer value. We do this by keeping
3376 track of blocks of Lisp data that are allocated in a red-black tree
3377 (see also the comment of mem_node which is the type of nodes in
3378 that tree). Function lisp_malloc adds information for an allocated
3379 block to the red-black tree with calls to mem_insert, and function
3380 lisp_free removes it with mem_delete. Functions live_string_p etc
3381 call mem_find to lookup information about a given pointer in the
3382 tree, and use that to determine if the pointer points to a Lisp
3383 object or not. */
3384
3385 /* Initialize this part of alloc.c. */
3386
3387 static void
3388 mem_init (void)
3389 {
3390 mem_z.left = mem_z.right = MEM_NIL;
3391 mem_z.parent = NULL;
3392 mem_z.color = MEM_BLACK;
3393 mem_z.start = mem_z.end = NULL;
3394 mem_root = MEM_NIL;
3395 }
3396
3397
3398 /* Value is a pointer to the mem_node containing START. Value is
3399 MEM_NIL if there is no node in the tree containing START. */
3400
3401 static inline struct mem_node *
3402 mem_find (void *start)
3403 {
3404 struct mem_node *p;
3405
3406 if (start < min_heap_address || start > max_heap_address)
3407 return MEM_NIL;
3408
3409 /* Make the search always successful to speed up the loop below. */
3410 mem_z.start = start;
3411 mem_z.end = (char *) start + 1;
3412
3413 p = mem_root;
3414 while (start < p->start || start >= p->end)
3415 p = start < p->start ? p->left : p->right;
3416 return p;
3417 }
3418
3419
3420 /* Insert a new node into the tree for a block of memory with start
3421 address START, end address END, and type TYPE. Value is a
3422 pointer to the node that was inserted. */
3423
3424 static struct mem_node *
3425 mem_insert (void *start, void *end, enum mem_type type)
3426 {
3427 struct mem_node *c, *parent, *x;
3428
3429 if (min_heap_address == NULL || start < min_heap_address)
3430 min_heap_address = start;
3431 if (max_heap_address == NULL || end > max_heap_address)
3432 max_heap_address = end;
3433
3434 /* See where in the tree a node for START belongs. In this
3435 particular application, it shouldn't happen that a node is already
3436 present. For debugging purposes, let's check that. */
3437 c = mem_root;
3438 parent = NULL;
3439
3440 #if GC_MARK_STACK != GC_MAKE_GCPROS_NOOPS
3441
3442 while (c != MEM_NIL)
3443 {
3444 if (start >= c->start && start < c->end)
3445 abort ();
3446 parent = c;
3447 c = start < c->start ? c->left : c->right;
3448 }
3449
3450 #else /* GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS */
3451
3452 while (c != MEM_NIL)
3453 {
3454 parent = c;
3455 c = start < c->start ? c->left : c->right;
3456 }
3457
3458 #endif /* GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS */
3459
3460 /* Create a new node. */
3461 #ifdef GC_MALLOC_CHECK
3462 x = (struct mem_node *) _malloc_internal (sizeof *x);
3463 if (x == NULL)
3464 abort ();
3465 #else
3466 x = (struct mem_node *) xmalloc (sizeof *x);
3467 #endif
3468 x->start = start;
3469 x->end = end;
3470 x->type = type;
3471 x->parent = parent;
3472 x->left = x->right = MEM_NIL;
3473 x->color = MEM_RED;
3474
3475 /* Insert it as child of PARENT or install it as root. */
3476 if (parent)
3477 {
3478 if (start < parent->start)
3479 parent->left = x;
3480 else
3481 parent->right = x;
3482 }
3483 else
3484 mem_root = x;
3485
3486 /* Re-establish red-black tree properties. */
3487 mem_insert_fixup (x);
3488
3489 return x;
3490 }
3491
3492
3493 /* Re-establish the red-black properties of the tree, and thereby
3494 balance the tree, after node X has been inserted; X is always red. */
3495
3496 static void
3497 mem_insert_fixup (struct mem_node *x)
3498 {
3499 while (x != mem_root && x->parent->color == MEM_RED)
3500 {
3501 /* X is red and its parent is red. This is a violation of
3502 red-black tree property #3. */
3503
3504 if (x->parent == x->parent->parent->left)
3505 {
3506 /* We're on the left side of our grandparent, and Y is our
3507 "uncle". */
3508 struct mem_node *y = x->parent->parent->right;
3509
3510 if (y->color == MEM_RED)
3511 {
3512 /* Uncle and parent are red but should be black because
3513 X is red. Change the colors accordingly and proceed
3514 with the grandparent. */
3515 x->parent->color = MEM_BLACK;
3516 y->color = MEM_BLACK;
3517 x->parent->parent->color = MEM_RED;
3518 x = x->parent->parent;
3519 }
3520 else
3521 {
3522 /* Parent and uncle have different colors; parent is
3523 red, uncle is black. */
3524 if (x == x->parent->right)
3525 {
3526 x = x->parent;
3527 mem_rotate_left (x);
3528 }
3529
3530 x->parent->color = MEM_BLACK;
3531 x->parent->parent->color = MEM_RED;
3532 mem_rotate_right (x->parent->parent);
3533 }
3534 }
3535 else
3536 {
3537 /* This is the symmetrical case of above. */
3538 struct mem_node *y = x->parent->parent->left;
3539
3540 if (y->color == MEM_RED)
3541 {
3542 x->parent->color = MEM_BLACK;
3543 y->color = MEM_BLACK;
3544 x->parent->parent->color = MEM_RED;
3545 x = x->parent->parent;
3546 }
3547 else
3548 {
3549 if (x == x->parent->left)
3550 {
3551 x = x->parent;
3552 mem_rotate_right (x);
3553 }
3554
3555 x->parent->color = MEM_BLACK;
3556 x->parent->parent->color = MEM_RED;
3557 mem_rotate_left (x->parent->parent);
3558 }
3559 }
3560 }
3561
3562 /* The root may have been changed to red due to the algorithm. Set
3563 it to black so that property #5 is satisfied. */
3564 mem_root->color = MEM_BLACK;
3565 }
3566
3567
3568 /* (x) (y)
3569 / \ / \
3570 a (y) ===> (x) c
3571 / \ / \
3572 b c a b */
3573
3574 static void
3575 mem_rotate_left (struct mem_node *x)
3576 {
3577 struct mem_node *y;
3578
3579 /* Turn y's left sub-tree into x's right sub-tree. */
3580 y = x->right;
3581 x->right = y->left;
3582 if (y->left != MEM_NIL)
3583 y->left->parent = x;
3584
3585 /* Y's parent was x's parent. */
3586 if (y != MEM_NIL)
3587 y->parent = x->parent;
3588
3589 /* Get the parent to point to y instead of x. */
3590 if (x->parent)
3591 {
3592 if (x == x->parent->left)
3593 x->parent->left = y;
3594 else
3595 x->parent->right = y;
3596 }
3597 else
3598 mem_root = y;
3599
3600 /* Put x on y's left. */
3601 y->left = x;
3602 if (x != MEM_NIL)
3603 x->parent = y;
3604 }
3605
3606
3607 /* (x) (Y)
3608 / \ / \
3609 (y) c ===> a (x)
3610 / \ / \
3611 a b b c */
3612
3613 static void
3614 mem_rotate_right (struct mem_node *x)
3615 {
3616 struct mem_node *y = x->left;
3617
3618 x->left = y->right;
3619 if (y->right != MEM_NIL)
3620 y->right->parent = x;
3621
3622 if (y != MEM_NIL)
3623 y->parent = x->parent;
3624 if (x->parent)
3625 {
3626 if (x == x->parent->right)
3627 x->parent->right = y;
3628 else
3629 x->parent->left = y;
3630 }
3631 else
3632 mem_root = y;
3633
3634 y->right = x;
3635 if (x != MEM_NIL)
3636 x->parent = y;
3637 }
3638
3639
3640 /* Delete node Z from the tree. If Z is null or MEM_NIL, do nothing. */
3641
3642 static void
3643 mem_delete (struct mem_node *z)
3644 {
3645 struct mem_node *x, *y;
3646
3647 if (!z || z == MEM_NIL)
3648 return;
3649
3650 if (z->left == MEM_NIL || z->right == MEM_NIL)
3651 y = z;
3652 else
3653 {
3654 y = z->right;
3655 while (y->left != MEM_NIL)
3656 y = y->left;
3657 }
3658
3659 if (y->left != MEM_NIL)
3660 x = y->left;
3661 else
3662 x = y->right;
3663
3664 x->parent = y->parent;
3665 if (y->parent)
3666 {
3667 if (y == y->parent->left)
3668 y->parent->left = x;
3669 else
3670 y->parent->right = x;
3671 }
3672 else
3673 mem_root = x;
3674
3675 if (y != z)
3676 {
3677 z->start = y->start;
3678 z->end = y->end;
3679 z->type = y->type;
3680 }
3681
3682 if (y->color == MEM_BLACK)
3683 mem_delete_fixup (x);
3684
3685 #ifdef GC_MALLOC_CHECK
3686 _free_internal (y);
3687 #else
3688 xfree (y);
3689 #endif
3690 }
3691
3692
3693 /* Re-establish the red-black properties of the tree, after a
3694 deletion. */
3695
3696 static void
3697 mem_delete_fixup (struct mem_node *x)
3698 {
3699 while (x != mem_root && x->color == MEM_BLACK)
3700 {
3701 if (x == x->parent->left)
3702 {
3703 struct mem_node *w = x->parent->right;
3704
3705 if (w->color == MEM_RED)
3706 {
3707 w->color = MEM_BLACK;
3708 x->parent->color = MEM_RED;
3709 mem_rotate_left (x->parent);
3710 w = x->parent->right;
3711 }
3712
3713 if (w->left->color == MEM_BLACK && w->right->color == MEM_BLACK)
3714 {
3715 w->color = MEM_RED;
3716 x = x->parent;
3717 }
3718 else
3719 {
3720 if (w->right->color == MEM_BLACK)
3721 {
3722 w->left->color = MEM_BLACK;
3723 w->color = MEM_RED;
3724 mem_rotate_right (w);
3725 w = x->parent->right;
3726 }
3727 w->color = x->parent->color;
3728 x->parent->color = MEM_BLACK;
3729 w->right->color = MEM_BLACK;
3730 mem_rotate_left (x->parent);
3731 x = mem_root;
3732 }
3733 }
3734 else
3735 {
3736 struct mem_node *w = x->parent->left;
3737
3738 if (w->color == MEM_RED)
3739 {
3740 w->color = MEM_BLACK;
3741 x->parent->color = MEM_RED;
3742 mem_rotate_right (x->parent);
3743 w = x->parent->left;
3744 }
3745
3746 if (w->right->color == MEM_BLACK && w->left->color == MEM_BLACK)
3747 {
3748 w->color = MEM_RED;
3749 x = x->parent;
3750 }
3751 else
3752 {
3753 if (w->left->color == MEM_BLACK)
3754 {
3755 w->right->color = MEM_BLACK;
3756 w->color = MEM_RED;
3757 mem_rotate_left (w);
3758 w = x->parent->left;
3759 }
3760
3761 w->color = x->parent->color;
3762 x->parent->color = MEM_BLACK;
3763 w->left->color = MEM_BLACK;
3764 mem_rotate_right (x->parent);
3765 x = mem_root;
3766 }
3767 }
3768 }
3769
3770 x->color = MEM_BLACK;
3771 }
3772
3773
3774 /* Value is non-zero if P is a pointer to a live Lisp string on
3775 the heap. M is a pointer to the mem_block for P. */
3776
3777 static inline int
3778 live_string_p (struct mem_node *m, void *p)
3779 {
3780 if (m->type == MEM_TYPE_STRING)
3781 {
3782 struct string_block *b = (struct string_block *) m->start;
3783 ptrdiff_t offset = (char *) p - (char *) &b->strings[0];
3784
3785 /* P must point to the start of a Lisp_String structure, and it
3786 must not be on the free-list. */
3787 return (offset >= 0
3788 && offset % sizeof b->strings[0] == 0
3789 && offset < (STRING_BLOCK_SIZE * sizeof b->strings[0])
3790 && ((struct Lisp_String *) p)->data != NULL);
3791 }
3792 else
3793 return 0;
3794 }
3795
3796
3797 /* Value is non-zero if P is a pointer to a live Lisp cons on
3798 the heap. M is a pointer to the mem_block for P. */
3799
3800 static inline int
3801 live_cons_p (struct mem_node *m, void *p)
3802 {
3803 if (m->type == MEM_TYPE_CONS)
3804 {
3805 struct cons_block *b = (struct cons_block *) m->start;
3806 ptrdiff_t offset = (char *) p - (char *) &b->conses[0];
3807
3808 /* P must point to the start of a Lisp_Cons, not be
3809 one of the unused cells in the current cons block,
3810 and not be on the free-list. */
3811 return (offset >= 0
3812 && offset % sizeof b->conses[0] == 0
3813 && offset < (CONS_BLOCK_SIZE * sizeof b->conses[0])
3814 && (b != cons_block
3815 || offset / sizeof b->conses[0] < cons_block_index)
3816 && !EQ (((struct Lisp_Cons *) p)->car, Vdead));
3817 }
3818 else
3819 return 0;
3820 }
3821
3822
3823 /* Value is non-zero if P is a pointer to a live Lisp symbol on
3824 the heap. M is a pointer to the mem_block for P. */
3825
3826 static inline int
3827 live_symbol_p (struct mem_node *m, void *p)
3828 {
3829 if (m->type == MEM_TYPE_SYMBOL)
3830 {
3831 struct symbol_block *b = (struct symbol_block *) m->start;
3832 ptrdiff_t offset = (char *) p - (char *) &b->symbols[0];
3833
3834 /* P must point to the start of a Lisp_Symbol, not be
3835 one of the unused cells in the current symbol block,
3836 and not be on the free-list. */
3837 return (offset >= 0
3838 && offset % sizeof b->symbols[0] == 0
3839 && offset < (SYMBOL_BLOCK_SIZE * sizeof b->symbols[0])
3840 && (b != symbol_block
3841 || offset / sizeof b->symbols[0] < symbol_block_index)
3842 && !EQ (((struct Lisp_Symbol *) p)->function, Vdead));
3843 }
3844 else
3845 return 0;
3846 }
3847
3848
3849 /* Value is non-zero if P is a pointer to a live Lisp float on
3850 the heap. M is a pointer to the mem_block for P. */
3851
3852 static inline int
3853 live_float_p (struct mem_node *m, void *p)
3854 {
3855 if (m->type == MEM_TYPE_FLOAT)
3856 {
3857 struct float_block *b = (struct float_block *) m->start;
3858 ptrdiff_t offset = (char *) p - (char *) &b->floats[0];
3859
3860 /* P must point to the start of a Lisp_Float and not be
3861 one of the unused cells in the current float block. */
3862 return (offset >= 0
3863 && offset % sizeof b->floats[0] == 0
3864 && offset < (FLOAT_BLOCK_SIZE * sizeof b->floats[0])
3865 && (b != float_block
3866 || offset / sizeof b->floats[0] < float_block_index));
3867 }
3868 else
3869 return 0;
3870 }
3871
3872
3873 /* Value is non-zero if P is a pointer to a live Lisp Misc on
3874 the heap. M is a pointer to the mem_block for P. */
3875
3876 static inline int
3877 live_misc_p (struct mem_node *m, void *p)
3878 {
3879 if (m->type == MEM_TYPE_MISC)
3880 {
3881 struct marker_block *b = (struct marker_block *) m->start;
3882 ptrdiff_t offset = (char *) p - (char *) &b->markers[0];
3883
3884 /* P must point to the start of a Lisp_Misc, not be
3885 one of the unused cells in the current misc block,
3886 and not be on the free-list. */
3887 return (offset >= 0
3888 && offset % sizeof b->markers[0] == 0
3889 && offset < (MARKER_BLOCK_SIZE * sizeof b->markers[0])
3890 && (b != marker_block
3891 || offset / sizeof b->markers[0] < marker_block_index)
3892 && ((union Lisp_Misc *) p)->u_any.type != Lisp_Misc_Free);
3893 }
3894 else
3895 return 0;
3896 }
3897
3898
3899 /* Value is non-zero if P is a pointer to a live vector-like object.
3900 M is a pointer to the mem_block for P. */
3901
3902 static inline int
3903 live_vector_p (struct mem_node *m, void *p)
3904 {
3905 return (p == m->start && m->type == MEM_TYPE_VECTORLIKE);
3906 }
3907
3908
3909 /* Value is non-zero if P is a pointer to a live buffer. M is a
3910 pointer to the mem_block for P. */
3911
3912 static inline int
3913 live_buffer_p (struct mem_node *m, void *p)
3914 {
3915 /* P must point to the start of the block, and the buffer
3916 must not have been killed. */
3917 return (m->type == MEM_TYPE_BUFFER
3918 && p == m->start
3919 && !NILP (((struct buffer *) p)->BUFFER_INTERNAL_FIELD (name)));
3920 }
3921
3922 #endif /* GC_MARK_STACK || defined GC_MALLOC_CHECK */
3923
3924 #if GC_MARK_STACK
3925
3926 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
3927
3928 /* Array of objects that are kept alive because the C stack contains
3929 a pattern that looks like a reference to them . */
3930
3931 #define MAX_ZOMBIES 10
3932 static Lisp_Object zombies[MAX_ZOMBIES];
3933
3934 /* Number of zombie objects. */
3935
3936 static int nzombies;
3937
3938 /* Number of garbage collections. */
3939
3940 static int ngcs;
3941
3942 /* Average percentage of zombies per collection. */
3943
3944 static double avg_zombies;
3945
3946 /* Max. number of live and zombie objects. */
3947
3948 static int max_live, max_zombies;
3949
3950 /* Average number of live objects per GC. */
3951
3952 static double avg_live;
3953
3954 DEFUN ("gc-status", Fgc_status, Sgc_status, 0, 0, "",
3955 doc: /* Show information about live and zombie objects. */)
3956 (void)
3957 {
3958 Lisp_Object args[8], zombie_list = Qnil;
3959 int i;
3960 for (i = 0; i < nzombies; i++)
3961 zombie_list = Fcons (zombies[i], zombie_list);
3962 args[0] = build_string ("%d GCs, avg live/zombies = %.2f/%.2f (%f%%), max %d/%d\nzombies: %S");
3963 args[1] = make_number (ngcs);
3964 args[2] = make_float (avg_live);
3965 args[3] = make_float (avg_zombies);
3966 args[4] = make_float (avg_zombies / avg_live / 100);
3967 args[5] = make_number (max_live);
3968 args[6] = make_number (max_zombies);
3969 args[7] = zombie_list;
3970 return Fmessage (8, args);
3971 }
3972
3973 #endif /* GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES */
3974
3975
3976 /* Mark OBJ if we can prove it's a Lisp_Object. */
3977
3978 static inline void
3979 mark_maybe_object (Lisp_Object obj)
3980 {
3981 void *po;
3982 struct mem_node *m;
3983
3984 if (INTEGERP (obj))
3985 return;
3986
3987 po = (void *) XPNTR (obj);
3988 m = mem_find (po);
3989
3990 if (m != MEM_NIL)
3991 {
3992 int mark_p = 0;
3993
3994 switch (XTYPE (obj))
3995 {
3996 case Lisp_String:
3997 mark_p = (live_string_p (m, po)
3998 && !STRING_MARKED_P ((struct Lisp_String *) po));
3999 break;
4000
4001 case Lisp_Cons:
4002 mark_p = (live_cons_p (m, po) && !CONS_MARKED_P (XCONS (obj)));
4003 break;
4004
4005 case Lisp_Symbol:
4006 mark_p = (live_symbol_p (m, po) && !XSYMBOL (obj)->gcmarkbit);
4007 break;
4008
4009 case Lisp_Float:
4010 mark_p = (live_float_p (m, po) && !FLOAT_MARKED_P (XFLOAT (obj)));
4011 break;
4012
4013 case Lisp_Vectorlike:
4014 /* Note: can't check BUFFERP before we know it's a
4015 buffer because checking that dereferences the pointer
4016 PO which might point anywhere. */
4017 if (live_vector_p (m, po))
4018 mark_p = !SUBRP (obj) && !VECTOR_MARKED_P (XVECTOR (obj));
4019 else if (live_buffer_p (m, po))
4020 mark_p = BUFFERP (obj) && !VECTOR_MARKED_P (XBUFFER (obj));
4021 break;
4022
4023 case Lisp_Misc:
4024 mark_p = (live_misc_p (m, po) && !XMISCANY (obj)->gcmarkbit);
4025 break;
4026
4027 default:
4028 break;
4029 }
4030
4031 if (mark_p)
4032 {
4033 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
4034 if (nzombies < MAX_ZOMBIES)
4035 zombies[nzombies] = obj;
4036 ++nzombies;
4037 #endif
4038 mark_object (obj);
4039 }
4040 }
4041 }
4042
4043
4044 /* If P points to Lisp data, mark that as live if it isn't already
4045 marked. */
4046
4047 static inline void
4048 mark_maybe_pointer (void *p)
4049 {
4050 struct mem_node *m;
4051
4052 /* Quickly rule out some values which can't point to Lisp data. */
4053 if ((intptr_t) p %
4054 #ifdef USE_LSB_TAG
4055 8 /* USE_LSB_TAG needs Lisp data to be aligned on multiples of 8. */
4056 #else
4057 2 /* We assume that Lisp data is aligned on even addresses. */
4058 #endif
4059 )
4060 return;
4061
4062 m = mem_find (p);
4063 if (m != MEM_NIL)
4064 {
4065 Lisp_Object obj = Qnil;
4066
4067 switch (m->type)
4068 {
4069 case MEM_TYPE_NON_LISP:
4070 /* Nothing to do; not a pointer to Lisp memory. */
4071 break;
4072
4073 case MEM_TYPE_BUFFER:
4074 if (live_buffer_p (m, p) && !VECTOR_MARKED_P((struct buffer *)p))
4075 XSETVECTOR (obj, p);
4076 break;
4077
4078 case MEM_TYPE_CONS:
4079 if (live_cons_p (m, p) && !CONS_MARKED_P ((struct Lisp_Cons *) p))
4080 XSETCONS (obj, p);
4081 break;
4082
4083 case MEM_TYPE_STRING:
4084 if (live_string_p (m, p)
4085 && !STRING_MARKED_P ((struct Lisp_String *) p))
4086 XSETSTRING (obj, p);
4087 break;
4088
4089 case MEM_TYPE_MISC:
4090 if (live_misc_p (m, p) && !((struct Lisp_Free *) p)->gcmarkbit)
4091 XSETMISC (obj, p);
4092 break;
4093
4094 case MEM_TYPE_SYMBOL:
4095 if (live_symbol_p (m, p) && !((struct Lisp_Symbol *) p)->gcmarkbit)
4096 XSETSYMBOL (obj, p);
4097 break;
4098
4099 case MEM_TYPE_FLOAT:
4100 if (live_float_p (m, p) && !FLOAT_MARKED_P (p))
4101 XSETFLOAT (obj, p);
4102 break;
4103
4104 case MEM_TYPE_VECTORLIKE:
4105 if (live_vector_p (m, p))
4106 {
4107 Lisp_Object tem;
4108 XSETVECTOR (tem, p);
4109 if (!SUBRP (tem) && !VECTOR_MARKED_P (XVECTOR (tem)))
4110 obj = tem;
4111 }
4112 break;
4113
4114 default:
4115 abort ();
4116 }
4117
4118 if (!NILP (obj))
4119 mark_object (obj);
4120 }
4121 }
4122
4123
4124 /* Mark Lisp objects referenced from the address range START+OFFSET..END
4125 or END+OFFSET..START. */
4126
4127 static void
4128 mark_memory (void *start, void *end, int offset)
4129 {
4130 Lisp_Object *p;
4131 void **pp;
4132
4133 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
4134 nzombies = 0;
4135 #endif
4136
4137 /* Make START the pointer to the start of the memory region,
4138 if it isn't already. */
4139 if (end < start)
4140 {
4141 void *tem = start;
4142 start = end;
4143 end = tem;
4144 }
4145
4146 /* Mark Lisp_Objects. */
4147 for (p = (Lisp_Object *) ((char *) start + offset); (void *) p < end; ++p)
4148 mark_maybe_object (*p);
4149
4150 /* Mark Lisp data pointed to. This is necessary because, in some
4151 situations, the C compiler optimizes Lisp objects away, so that
4152 only a pointer to them remains. Example:
4153
4154 DEFUN ("testme", Ftestme, Stestme, 0, 0, 0, "")
4155 ()
4156 {
4157 Lisp_Object obj = build_string ("test");
4158 struct Lisp_String *s = XSTRING (obj);
4159 Fgarbage_collect ();
4160 fprintf (stderr, "test `%s'\n", s->data);
4161 return Qnil;
4162 }
4163
4164 Here, `obj' isn't really used, and the compiler optimizes it
4165 away. The only reference to the life string is through the
4166 pointer `s'. */
4167
4168 for (pp = (void **) ((char *) start + offset); (void *) pp < end; ++pp)
4169 mark_maybe_pointer (*pp);
4170 }
4171
4172 /* setjmp will work with GCC unless NON_SAVING_SETJMP is defined in
4173 the GCC system configuration. In gcc 3.2, the only systems for
4174 which this is so are i386-sco5 non-ELF, i386-sysv3 (maybe included
4175 by others?) and ns32k-pc532-min. */
4176
4177 #if !defined GC_SAVE_REGISTERS_ON_STACK && !defined GC_SETJMP_WORKS
4178
4179 static int setjmp_tested_p, longjmps_done;
4180
4181 #define SETJMP_WILL_LIKELY_WORK "\
4182 \n\
4183 Emacs garbage collector has been changed to use conservative stack\n\
4184 marking. Emacs has determined that the method it uses to do the\n\
4185 marking will likely work on your system, but this isn't sure.\n\
4186 \n\
4187 If you are a system-programmer, or can get the help of a local wizard\n\
4188 who is, please take a look at the function mark_stack in alloc.c, and\n\
4189 verify that the methods used are appropriate for your system.\n\
4190 \n\
4191 Please mail the result to <emacs-devel@gnu.org>.\n\
4192 "
4193
4194 #define SETJMP_WILL_NOT_WORK "\
4195 \n\
4196 Emacs garbage collector has been changed to use conservative stack\n\
4197 marking. Emacs has determined that the default method it uses to do the\n\
4198 marking will not work on your system. We will need a system-dependent\n\
4199 solution for your system.\n\
4200 \n\
4201 Please take a look at the function mark_stack in alloc.c, and\n\
4202 try to find a way to make it work on your system.\n\
4203 \n\
4204 Note that you may get false negatives, depending on the compiler.\n\
4205 In particular, you need to use -O with GCC for this test.\n\
4206 \n\
4207 Please mail the result to <emacs-devel@gnu.org>.\n\
4208 "
4209
4210
4211 /* Perform a quick check if it looks like setjmp saves registers in a
4212 jmp_buf. Print a message to stderr saying so. When this test
4213 succeeds, this is _not_ a proof that setjmp is sufficient for
4214 conservative stack marking. Only the sources or a disassembly
4215 can prove that. */
4216
4217 static void
4218 test_setjmp (void)
4219 {
4220 char buf[10];
4221 register int x;
4222 jmp_buf jbuf;
4223 int result = 0;
4224
4225 /* Arrange for X to be put in a register. */
4226 sprintf (buf, "1");
4227 x = strlen (buf);
4228 x = 2 * x - 1;
4229
4230 setjmp (jbuf);
4231 if (longjmps_done == 1)
4232 {
4233 /* Came here after the longjmp at the end of the function.
4234
4235 If x == 1, the longjmp has restored the register to its
4236 value before the setjmp, and we can hope that setjmp
4237 saves all such registers in the jmp_buf, although that
4238 isn't sure.
4239
4240 For other values of X, either something really strange is
4241 taking place, or the setjmp just didn't save the register. */
4242
4243 if (x == 1)
4244 fprintf (stderr, SETJMP_WILL_LIKELY_WORK);
4245 else
4246 {
4247 fprintf (stderr, SETJMP_WILL_NOT_WORK);
4248 exit (1);
4249 }
4250 }
4251
4252 ++longjmps_done;
4253 x = 2;
4254 if (longjmps_done == 1)
4255 longjmp (jbuf, 1);
4256 }
4257
4258 #endif /* not GC_SAVE_REGISTERS_ON_STACK && not GC_SETJMP_WORKS */
4259
4260
4261 #if GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS
4262
4263 /* Abort if anything GCPRO'd doesn't survive the GC. */
4264
4265 static void
4266 check_gcpros (void)
4267 {
4268 struct gcpro *p;
4269 size_t i;
4270
4271 for (p = gcprolist; p; p = p->next)
4272 for (i = 0; i < p->nvars; ++i)
4273 if (!survives_gc_p (p->var[i]))
4274 /* FIXME: It's not necessarily a bug. It might just be that the
4275 GCPRO is unnecessary or should release the object sooner. */
4276 abort ();
4277 }
4278
4279 #elif GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
4280
4281 static void
4282 dump_zombies (void)
4283 {
4284 int i;
4285
4286 fprintf (stderr, "\nZombies kept alive = %d:\n", nzombies);
4287 for (i = 0; i < min (MAX_ZOMBIES, nzombies); ++i)
4288 {
4289 fprintf (stderr, " %d = ", i);
4290 debug_print (zombies[i]);
4291 }
4292 }
4293
4294 #endif /* GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES */
4295
4296
4297 /* Mark live Lisp objects on the C stack.
4298
4299 There are several system-dependent problems to consider when
4300 porting this to new architectures:
4301
4302 Processor Registers
4303
4304 We have to mark Lisp objects in CPU registers that can hold local
4305 variables or are used to pass parameters.
4306
4307 If GC_SAVE_REGISTERS_ON_STACK is defined, it should expand to
4308 something that either saves relevant registers on the stack, or
4309 calls mark_maybe_object passing it each register's contents.
4310
4311 If GC_SAVE_REGISTERS_ON_STACK is not defined, the current
4312 implementation assumes that calling setjmp saves registers we need
4313 to see in a jmp_buf which itself lies on the stack. This doesn't
4314 have to be true! It must be verified for each system, possibly
4315 by taking a look at the source code of setjmp.
4316
4317 If __builtin_unwind_init is available (defined by GCC >= 2.8) we
4318 can use it as a machine independent method to store all registers
4319 to the stack. In this case the macros described in the previous
4320 two paragraphs are not used.
4321
4322 Stack Layout
4323
4324 Architectures differ in the way their processor stack is organized.
4325 For example, the stack might look like this
4326
4327 +----------------+
4328 | Lisp_Object | size = 4
4329 +----------------+
4330 | something else | size = 2
4331 +----------------+
4332 | Lisp_Object | size = 4
4333 +----------------+
4334 | ... |
4335
4336 In such a case, not every Lisp_Object will be aligned equally. To
4337 find all Lisp_Object on the stack it won't be sufficient to walk
4338 the stack in steps of 4 bytes. Instead, two passes will be
4339 necessary, one starting at the start of the stack, and a second
4340 pass starting at the start of the stack + 2. Likewise, if the
4341 minimal alignment of Lisp_Objects on the stack is 1, four passes
4342 would be necessary, each one starting with one byte more offset
4343 from the stack start.
4344
4345 The current code assumes by default that Lisp_Objects are aligned
4346 equally on the stack. */
4347
4348 static void
4349 mark_stack (void)
4350 {
4351 int i;
4352 void *end;
4353
4354 #ifdef HAVE___BUILTIN_UNWIND_INIT
4355 /* Force callee-saved registers and register windows onto the stack.
4356 This is the preferred method if available, obviating the need for
4357 machine dependent methods. */
4358 __builtin_unwind_init ();
4359 end = &end;
4360 #else /* not HAVE___BUILTIN_UNWIND_INIT */
4361 #ifndef GC_SAVE_REGISTERS_ON_STACK
4362 /* jmp_buf may not be aligned enough on darwin-ppc64 */
4363 union aligned_jmpbuf {
4364 Lisp_Object o;
4365 jmp_buf j;
4366 } j;
4367 volatile int stack_grows_down_p = (char *) &j > (char *) stack_base;
4368 #endif
4369 /* This trick flushes the register windows so that all the state of
4370 the process is contained in the stack. */
4371 /* Fixme: Code in the Boehm GC suggests flushing (with `flushrs') is
4372 needed on ia64 too. See mach_dep.c, where it also says inline
4373 assembler doesn't work with relevant proprietary compilers. */
4374 #ifdef __sparc__
4375 #if defined (__sparc64__) && defined (__FreeBSD__)
4376 /* FreeBSD does not have a ta 3 handler. */
4377 asm ("flushw");
4378 #else
4379 asm ("ta 3");
4380 #endif
4381 #endif
4382
4383 /* Save registers that we need to see on the stack. We need to see
4384 registers used to hold register variables and registers used to
4385 pass parameters. */
4386 #ifdef GC_SAVE_REGISTERS_ON_STACK
4387 GC_SAVE_REGISTERS_ON_STACK (end);
4388 #else /* not GC_SAVE_REGISTERS_ON_STACK */
4389
4390 #ifndef GC_SETJMP_WORKS /* If it hasn't been checked yet that
4391 setjmp will definitely work, test it
4392 and print a message with the result
4393 of the test. */
4394 if (!setjmp_tested_p)
4395 {
4396 setjmp_tested_p = 1;
4397 test_setjmp ();
4398 }
4399 #endif /* GC_SETJMP_WORKS */
4400
4401 setjmp (j.j);
4402 end = stack_grows_down_p ? (char *) &j + sizeof j : (char *) &j;
4403 #endif /* not GC_SAVE_REGISTERS_ON_STACK */
4404 #endif /* not HAVE___BUILTIN_UNWIND_INIT */
4405
4406 /* This assumes that the stack is a contiguous region in memory. If
4407 that's not the case, something has to be done here to iterate
4408 over the stack segments. */
4409 #ifndef GC_LISP_OBJECT_ALIGNMENT
4410 #ifdef __GNUC__
4411 #define GC_LISP_OBJECT_ALIGNMENT __alignof__ (Lisp_Object)
4412 #else
4413 #define GC_LISP_OBJECT_ALIGNMENT sizeof (Lisp_Object)
4414 #endif
4415 #endif
4416 for (i = 0; i < sizeof (Lisp_Object); i += GC_LISP_OBJECT_ALIGNMENT)
4417 mark_memory (stack_base, end, i);
4418 /* Allow for marking a secondary stack, like the register stack on the
4419 ia64. */
4420 #ifdef GC_MARK_SECONDARY_STACK
4421 GC_MARK_SECONDARY_STACK ();
4422 #endif
4423
4424 #if GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS
4425 check_gcpros ();
4426 #endif
4427 }
4428
4429 #endif /* GC_MARK_STACK != 0 */
4430
4431
4432 /* Determine whether it is safe to access memory at address P. */
4433 static int
4434 valid_pointer_p (void *p)
4435 {
4436 #ifdef WINDOWSNT
4437 return w32_valid_pointer_p (p, 16);
4438 #else
4439 int fd;
4440
4441 /* Obviously, we cannot just access it (we would SEGV trying), so we
4442 trick the o/s to tell us whether p is a valid pointer.
4443 Unfortunately, we cannot use NULL_DEVICE here, as emacs_write may
4444 not validate p in that case. */
4445
4446 if ((fd = emacs_open ("__Valid__Lisp__Object__", O_CREAT | O_WRONLY | O_TRUNC, 0666)) >= 0)
4447 {
4448 int valid = (emacs_write (fd, (char *)p, 16) == 16);
4449 emacs_close (fd);
4450 unlink ("__Valid__Lisp__Object__");
4451 return valid;
4452 }
4453
4454 return -1;
4455 #endif
4456 }
4457
4458 /* Return 1 if OBJ is a valid lisp object.
4459 Return 0 if OBJ is NOT a valid lisp object.
4460 Return -1 if we cannot validate OBJ.
4461 This function can be quite slow,
4462 so it should only be used in code for manual debugging. */
4463
4464 int
4465 valid_lisp_object_p (Lisp_Object obj)
4466 {
4467 void *p;
4468 #if GC_MARK_STACK
4469 struct mem_node *m;
4470 #endif
4471
4472 if (INTEGERP (obj))
4473 return 1;
4474
4475 p = (void *) XPNTR (obj);
4476 if (PURE_POINTER_P (p))
4477 return 1;
4478
4479 #if !GC_MARK_STACK
4480 return valid_pointer_p (p);
4481 #else
4482
4483 m = mem_find (p);
4484
4485 if (m == MEM_NIL)
4486 {
4487 int valid = valid_pointer_p (p);
4488 if (valid <= 0)
4489 return valid;
4490
4491 if (SUBRP (obj))
4492 return 1;
4493
4494 return 0;
4495 }
4496
4497 switch (m->type)
4498 {
4499 case MEM_TYPE_NON_LISP:
4500 return 0;
4501
4502 case MEM_TYPE_BUFFER:
4503 return live_buffer_p (m, p);
4504
4505 case MEM_TYPE_CONS:
4506 return live_cons_p (m, p);
4507
4508 case MEM_TYPE_STRING:
4509 return live_string_p (m, p);
4510
4511 case MEM_TYPE_MISC:
4512 return live_misc_p (m, p);
4513
4514 case MEM_TYPE_SYMBOL:
4515 return live_symbol_p (m, p);
4516
4517 case MEM_TYPE_FLOAT:
4518 return live_float_p (m, p);
4519
4520 case MEM_TYPE_VECTORLIKE:
4521 return live_vector_p (m, p);
4522
4523 default:
4524 break;
4525 }
4526
4527 return 0;
4528 #endif
4529 }
4530
4531
4532
4533 \f
4534 /***********************************************************************
4535 Pure Storage Management
4536 ***********************************************************************/
4537
4538 /* Allocate room for SIZE bytes from pure Lisp storage and return a
4539 pointer to it. TYPE is the Lisp type for which the memory is
4540 allocated. TYPE < 0 means it's not used for a Lisp object. */
4541
4542 static POINTER_TYPE *
4543 pure_alloc (size_t size, int type)
4544 {
4545 POINTER_TYPE *result;
4546 #ifdef USE_LSB_TAG
4547 size_t alignment = (1 << GCTYPEBITS);
4548 #else
4549 size_t alignment = sizeof (EMACS_INT);
4550
4551 /* Give Lisp_Floats an extra alignment. */
4552 if (type == Lisp_Float)
4553 {
4554 #if defined __GNUC__ && __GNUC__ >= 2
4555 alignment = __alignof (struct Lisp_Float);
4556 #else
4557 alignment = sizeof (struct Lisp_Float);
4558 #endif
4559 }
4560 #endif
4561
4562 again:
4563 if (type >= 0)
4564 {
4565 /* Allocate space for a Lisp object from the beginning of the free
4566 space with taking account of alignment. */
4567 result = ALIGN (purebeg + pure_bytes_used_lisp, alignment);
4568 pure_bytes_used_lisp = ((char *)result - (char *)purebeg) + size;
4569 }
4570 else
4571 {
4572 /* Allocate space for a non-Lisp object from the end of the free
4573 space. */
4574 pure_bytes_used_non_lisp += size;
4575 result = purebeg + pure_size - pure_bytes_used_non_lisp;
4576 }
4577 pure_bytes_used = pure_bytes_used_lisp + pure_bytes_used_non_lisp;
4578
4579 if (pure_bytes_used <= pure_size)
4580 return result;
4581
4582 /* Don't allocate a large amount here,
4583 because it might get mmap'd and then its address
4584 might not be usable. */
4585 purebeg = (char *) xmalloc (10000);
4586 pure_size = 10000;
4587 pure_bytes_used_before_overflow += pure_bytes_used - size;
4588 pure_bytes_used = 0;
4589 pure_bytes_used_lisp = pure_bytes_used_non_lisp = 0;
4590 goto again;
4591 }
4592
4593
4594 /* Print a warning if PURESIZE is too small. */
4595
4596 void
4597 check_pure_size (void)
4598 {
4599 if (pure_bytes_used_before_overflow)
4600 message (("emacs:0:Pure Lisp storage overflow (approx. %"pI"d"
4601 " bytes needed)"),
4602 pure_bytes_used + pure_bytes_used_before_overflow);
4603 }
4604
4605
4606 /* Find the byte sequence {DATA[0], ..., DATA[NBYTES-1], '\0'} from
4607 the non-Lisp data pool of the pure storage, and return its start
4608 address. Return NULL if not found. */
4609
4610 static char *
4611 find_string_data_in_pure (const char *data, EMACS_INT nbytes)
4612 {
4613 int i;
4614 EMACS_INT skip, bm_skip[256], last_char_skip, infinity, start, start_max;
4615 const unsigned char *p;
4616 char *non_lisp_beg;
4617
4618 if (pure_bytes_used_non_lisp < nbytes + 1)
4619 return NULL;
4620
4621 /* Set up the Boyer-Moore table. */
4622 skip = nbytes + 1;
4623 for (i = 0; i < 256; i++)
4624 bm_skip[i] = skip;
4625
4626 p = (const unsigned char *) data;
4627 while (--skip > 0)
4628 bm_skip[*p++] = skip;
4629
4630 last_char_skip = bm_skip['\0'];
4631
4632 non_lisp_beg = purebeg + pure_size - pure_bytes_used_non_lisp;
4633 start_max = pure_bytes_used_non_lisp - (nbytes + 1);
4634
4635 /* See the comments in the function `boyer_moore' (search.c) for the
4636 use of `infinity'. */
4637 infinity = pure_bytes_used_non_lisp + 1;
4638 bm_skip['\0'] = infinity;
4639
4640 p = (const unsigned char *) non_lisp_beg + nbytes;
4641 start = 0;
4642 do
4643 {
4644 /* Check the last character (== '\0'). */
4645 do
4646 {
4647 start += bm_skip[*(p + start)];
4648 }
4649 while (start <= start_max);
4650
4651 if (start < infinity)
4652 /* Couldn't find the last character. */
4653 return NULL;
4654
4655 /* No less than `infinity' means we could find the last
4656 character at `p[start - infinity]'. */
4657 start -= infinity;
4658
4659 /* Check the remaining characters. */
4660 if (memcmp (data, non_lisp_beg + start, nbytes) == 0)
4661 /* Found. */
4662 return non_lisp_beg + start;
4663
4664 start += last_char_skip;
4665 }
4666 while (start <= start_max);
4667
4668 return NULL;
4669 }
4670
4671
4672 /* Return a string allocated in pure space. DATA is a buffer holding
4673 NCHARS characters, and NBYTES bytes of string data. MULTIBYTE
4674 non-zero means make the result string multibyte.
4675
4676 Must get an error if pure storage is full, since if it cannot hold
4677 a large string it may be able to hold conses that point to that
4678 string; then the string is not protected from gc. */
4679
4680 Lisp_Object
4681 make_pure_string (const char *data,
4682 EMACS_INT nchars, EMACS_INT nbytes, int multibyte)
4683 {
4684 Lisp_Object string;
4685 struct Lisp_String *s;
4686
4687 s = (struct Lisp_String *) pure_alloc (sizeof *s, Lisp_String);
4688 s->data = (unsigned char *) find_string_data_in_pure (data, nbytes);
4689 if (s->data == NULL)
4690 {
4691 s->data = (unsigned char *) pure_alloc (nbytes + 1, -1);
4692 memcpy (s->data, data, nbytes);
4693 s->data[nbytes] = '\0';
4694 }
4695 s->size = nchars;
4696 s->size_byte = multibyte ? nbytes : -1;
4697 s->intervals = NULL_INTERVAL;
4698 XSETSTRING (string, s);
4699 return string;
4700 }
4701
4702 /* Return a string a string allocated in pure space. Do not allocate
4703 the string data, just point to DATA. */
4704
4705 Lisp_Object
4706 make_pure_c_string (const char *data)
4707 {
4708 Lisp_Object string;
4709 struct Lisp_String *s;
4710 EMACS_INT nchars = strlen (data);
4711
4712 s = (struct Lisp_String *) pure_alloc (sizeof *s, Lisp_String);
4713 s->size = nchars;
4714 s->size_byte = -1;
4715 s->data = (unsigned char *) data;
4716 s->intervals = NULL_INTERVAL;
4717 XSETSTRING (string, s);
4718 return string;
4719 }
4720
4721 /* Return a cons allocated from pure space. Give it pure copies
4722 of CAR as car and CDR as cdr. */
4723
4724 Lisp_Object
4725 pure_cons (Lisp_Object car, Lisp_Object cdr)
4726 {
4727 register Lisp_Object new;
4728 struct Lisp_Cons *p;
4729
4730 p = (struct Lisp_Cons *) pure_alloc (sizeof *p, Lisp_Cons);
4731 XSETCONS (new, p);
4732 XSETCAR (new, Fpurecopy (car));
4733 XSETCDR (new, Fpurecopy (cdr));
4734 return new;
4735 }
4736
4737
4738 /* Value is a float object with value NUM allocated from pure space. */
4739
4740 static Lisp_Object
4741 make_pure_float (double num)
4742 {
4743 register Lisp_Object new;
4744 struct Lisp_Float *p;
4745
4746 p = (struct Lisp_Float *) pure_alloc (sizeof *p, Lisp_Float);
4747 XSETFLOAT (new, p);
4748 XFLOAT_INIT (new, num);
4749 return new;
4750 }
4751
4752
4753 /* Return a vector with room for LEN Lisp_Objects allocated from
4754 pure space. */
4755
4756 Lisp_Object
4757 make_pure_vector (EMACS_INT len)
4758 {
4759 Lisp_Object new;
4760 struct Lisp_Vector *p;
4761 size_t size = (offsetof (struct Lisp_Vector, contents)
4762 + len * sizeof (Lisp_Object));
4763
4764 p = (struct Lisp_Vector *) pure_alloc (size, Lisp_Vectorlike);
4765 XSETVECTOR (new, p);
4766 XVECTOR (new)->header.size = len;
4767 return new;
4768 }
4769
4770
4771 DEFUN ("purecopy", Fpurecopy, Spurecopy, 1, 1, 0,
4772 doc: /* Make a copy of object OBJ in pure storage.
4773 Recursively copies contents of vectors and cons cells.
4774 Does not copy symbols. Copies strings without text properties. */)
4775 (register Lisp_Object obj)
4776 {
4777 if (NILP (Vpurify_flag))
4778 return obj;
4779
4780 if (PURE_POINTER_P (XPNTR (obj)))
4781 return obj;
4782
4783 if (HASH_TABLE_P (Vpurify_flag)) /* Hash consing. */
4784 {
4785 Lisp_Object tmp = Fgethash (obj, Vpurify_flag, Qnil);
4786 if (!NILP (tmp))
4787 return tmp;
4788 }
4789
4790 if (CONSP (obj))
4791 obj = pure_cons (XCAR (obj), XCDR (obj));
4792 else if (FLOATP (obj))
4793 obj = make_pure_float (XFLOAT_DATA (obj));
4794 else if (STRINGP (obj))
4795 obj = make_pure_string (SSDATA (obj), SCHARS (obj),
4796 SBYTES (obj),
4797 STRING_MULTIBYTE (obj));
4798 else if (COMPILEDP (obj) || VECTORP (obj))
4799 {
4800 register struct Lisp_Vector *vec;
4801 register EMACS_INT i;
4802 EMACS_INT size;
4803
4804 size = ASIZE (obj);
4805 if (size & PSEUDOVECTOR_FLAG)
4806 size &= PSEUDOVECTOR_SIZE_MASK;
4807 vec = XVECTOR (make_pure_vector (size));
4808 for (i = 0; i < size; i++)
4809 vec->contents[i] = Fpurecopy (XVECTOR (obj)->contents[i]);
4810 if (COMPILEDP (obj))
4811 {
4812 XSETPVECTYPE (vec, PVEC_COMPILED);
4813 XSETCOMPILED (obj, vec);
4814 }
4815 else
4816 XSETVECTOR (obj, vec);
4817 }
4818 else if (MARKERP (obj))
4819 error ("Attempt to copy a marker to pure storage");
4820 else
4821 /* Not purified, don't hash-cons. */
4822 return obj;
4823
4824 if (HASH_TABLE_P (Vpurify_flag)) /* Hash consing. */
4825 Fputhash (obj, obj, Vpurify_flag);
4826
4827 return obj;
4828 }
4829
4830
4831 \f
4832 /***********************************************************************
4833 Protection from GC
4834 ***********************************************************************/
4835
4836 /* Put an entry in staticvec, pointing at the variable with address
4837 VARADDRESS. */
4838
4839 void
4840 staticpro (Lisp_Object *varaddress)
4841 {
4842 staticvec[staticidx++] = varaddress;
4843 if (staticidx >= NSTATICS)
4844 abort ();
4845 }
4846
4847 \f
4848 /***********************************************************************
4849 Protection from GC
4850 ***********************************************************************/
4851
4852 /* Temporarily prevent garbage collection. */
4853
4854 int
4855 inhibit_garbage_collection (void)
4856 {
4857 int count = SPECPDL_INDEX ();
4858 int nbits = min (VALBITS, BITS_PER_INT);
4859
4860 specbind (Qgc_cons_threshold, make_number (((EMACS_INT) 1 << (nbits - 1)) - 1));
4861 return count;
4862 }
4863
4864
4865 DEFUN ("garbage-collect", Fgarbage_collect, Sgarbage_collect, 0, 0, "",
4866 doc: /* Reclaim storage for Lisp objects no longer needed.
4867 Garbage collection happens automatically if you cons more than
4868 `gc-cons-threshold' bytes of Lisp data since previous garbage collection.
4869 `garbage-collect' normally returns a list with info on amount of space in use:
4870 ((USED-CONSES . FREE-CONSES) (USED-SYMS . FREE-SYMS)
4871 (USED-MARKERS . FREE-MARKERS) USED-STRING-CHARS USED-VECTOR-SLOTS
4872 (USED-FLOATS . FREE-FLOATS) (USED-INTERVALS . FREE-INTERVALS)
4873 (USED-STRINGS . FREE-STRINGS))
4874 However, if there was overflow in pure space, `garbage-collect'
4875 returns nil, because real GC can't be done. */)
4876 (void)
4877 {
4878 register struct specbinding *bind;
4879 char stack_top_variable;
4880 register size_t i;
4881 int message_p;
4882 Lisp_Object total[8];
4883 int count = SPECPDL_INDEX ();
4884 EMACS_TIME t1, t2, t3;
4885
4886 if (abort_on_gc)
4887 abort ();
4888
4889 /* Can't GC if pure storage overflowed because we can't determine
4890 if something is a pure object or not. */
4891 if (pure_bytes_used_before_overflow)
4892 return Qnil;
4893
4894 CHECK_CONS_LIST ();
4895
4896 /* Don't keep undo information around forever.
4897 Do this early on, so it is no problem if the user quits. */
4898 {
4899 register struct buffer *nextb = all_buffers;
4900
4901 while (nextb)
4902 {
4903 /* If a buffer's undo list is Qt, that means that undo is
4904 turned off in that buffer. Calling truncate_undo_list on
4905 Qt tends to return NULL, which effectively turns undo back on.
4906 So don't call truncate_undo_list if undo_list is Qt. */
4907 if (! NILP (nextb->BUFFER_INTERNAL_FIELD (name)) && ! EQ (nextb->BUFFER_INTERNAL_FIELD (undo_list), Qt))
4908 truncate_undo_list (nextb);
4909
4910 /* Shrink buffer gaps, but skip indirect and dead buffers. */
4911 if (nextb->base_buffer == 0 && !NILP (nextb->BUFFER_INTERNAL_FIELD (name))
4912 && ! nextb->text->inhibit_shrinking)
4913 {
4914 /* If a buffer's gap size is more than 10% of the buffer
4915 size, or larger than 2000 bytes, then shrink it
4916 accordingly. Keep a minimum size of 20 bytes. */
4917 int size = min (2000, max (20, (nextb->text->z_byte / 10)));
4918
4919 if (nextb->text->gap_size > size)
4920 {
4921 struct buffer *save_current = current_buffer;
4922 current_buffer = nextb;
4923 make_gap (-(nextb->text->gap_size - size));
4924 current_buffer = save_current;
4925 }
4926 }
4927
4928 nextb = nextb->header.next.buffer;
4929 }
4930 }
4931
4932 EMACS_GET_TIME (t1);
4933
4934 /* In case user calls debug_print during GC,
4935 don't let that cause a recursive GC. */
4936 consing_since_gc = 0;
4937
4938 /* Save what's currently displayed in the echo area. */
4939 message_p = push_message ();
4940 record_unwind_protect (pop_message_unwind, Qnil);
4941
4942 /* Save a copy of the contents of the stack, for debugging. */
4943 #if MAX_SAVE_STACK > 0
4944 if (NILP (Vpurify_flag))
4945 {
4946 char *stack;
4947 size_t stack_size;
4948 if (&stack_top_variable < stack_bottom)
4949 {
4950 stack = &stack_top_variable;
4951 stack_size = stack_bottom - &stack_top_variable;
4952 }
4953 else
4954 {
4955 stack = stack_bottom;
4956 stack_size = &stack_top_variable - stack_bottom;
4957 }
4958 if (stack_size <= MAX_SAVE_STACK)
4959 {
4960 if (stack_copy_size < stack_size)
4961 {
4962 stack_copy = (char *) xrealloc (stack_copy, stack_size);
4963 stack_copy_size = stack_size;
4964 }
4965 memcpy (stack_copy, stack, stack_size);
4966 }
4967 }
4968 #endif /* MAX_SAVE_STACK > 0 */
4969
4970 if (garbage_collection_messages)
4971 message1_nolog ("Garbage collecting...");
4972
4973 BLOCK_INPUT;
4974
4975 shrink_regexp_cache ();
4976
4977 gc_in_progress = 1;
4978
4979 /* clear_marks (); */
4980
4981 /* Mark all the special slots that serve as the roots of accessibility. */
4982
4983 for (i = 0; i < staticidx; i++)
4984 mark_object (*staticvec[i]);
4985
4986 for (bind = specpdl; bind != specpdl_ptr; bind++)
4987 {
4988 mark_object (bind->symbol);
4989 mark_object (bind->old_value);
4990 }
4991 mark_terminals ();
4992 mark_kboards ();
4993 mark_ttys ();
4994
4995 #ifdef USE_GTK
4996 {
4997 extern void xg_mark_data (void);
4998 xg_mark_data ();
4999 }
5000 #endif
5001
5002 #if (GC_MARK_STACK == GC_MAKE_GCPROS_NOOPS \
5003 || GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS)
5004 mark_stack ();
5005 #else
5006 {
5007 register struct gcpro *tail;
5008 for (tail = gcprolist; tail; tail = tail->next)
5009 for (i = 0; i < tail->nvars; i++)
5010 mark_object (tail->var[i]);
5011 }
5012 mark_byte_stack ();
5013 {
5014 struct catchtag *catch;
5015 struct handler *handler;
5016
5017 for (catch = catchlist; catch; catch = catch->next)
5018 {
5019 mark_object (catch->tag);
5020 mark_object (catch->val);
5021 }
5022 for (handler = handlerlist; handler; handler = handler->next)
5023 {
5024 mark_object (handler->handler);
5025 mark_object (handler->var);
5026 }
5027 }
5028 mark_backtrace ();
5029 #endif
5030
5031 #ifdef HAVE_WINDOW_SYSTEM
5032 mark_fringe_data ();
5033 #endif
5034
5035 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
5036 mark_stack ();
5037 #endif
5038
5039 /* Everything is now marked, except for the things that require special
5040 finalization, i.e. the undo_list.
5041 Look thru every buffer's undo list
5042 for elements that update markers that were not marked,
5043 and delete them. */
5044 {
5045 register struct buffer *nextb = all_buffers;
5046
5047 while (nextb)
5048 {
5049 /* If a buffer's undo list is Qt, that means that undo is
5050 turned off in that buffer. Calling truncate_undo_list on
5051 Qt tends to return NULL, which effectively turns undo back on.
5052 So don't call truncate_undo_list if undo_list is Qt. */
5053 if (! EQ (nextb->BUFFER_INTERNAL_FIELD (undo_list), Qt))
5054 {
5055 Lisp_Object tail, prev;
5056 tail = nextb->BUFFER_INTERNAL_FIELD (undo_list);
5057 prev = Qnil;
5058 while (CONSP (tail))
5059 {
5060 if (CONSP (XCAR (tail))
5061 && MARKERP (XCAR (XCAR (tail)))
5062 && !XMARKER (XCAR (XCAR (tail)))->gcmarkbit)
5063 {
5064 if (NILP (prev))
5065 nextb->BUFFER_INTERNAL_FIELD (undo_list) = tail = XCDR (tail);
5066 else
5067 {
5068 tail = XCDR (tail);
5069 XSETCDR (prev, tail);
5070 }
5071 }
5072 else
5073 {
5074 prev = tail;
5075 tail = XCDR (tail);
5076 }
5077 }
5078 }
5079 /* Now that we have stripped the elements that need not be in the
5080 undo_list any more, we can finally mark the list. */
5081 mark_object (nextb->BUFFER_INTERNAL_FIELD (undo_list));
5082
5083 nextb = nextb->header.next.buffer;
5084 }
5085 }
5086
5087 gc_sweep ();
5088
5089 /* Clear the mark bits that we set in certain root slots. */
5090
5091 unmark_byte_stack ();
5092 VECTOR_UNMARK (&buffer_defaults);
5093 VECTOR_UNMARK (&buffer_local_symbols);
5094
5095 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES && 0
5096 dump_zombies ();
5097 #endif
5098
5099 UNBLOCK_INPUT;
5100
5101 CHECK_CONS_LIST ();
5102
5103 /* clear_marks (); */
5104 gc_in_progress = 0;
5105
5106 consing_since_gc = 0;
5107 if (gc_cons_threshold < 10000)
5108 gc_cons_threshold = 10000;
5109
5110 if (FLOATP (Vgc_cons_percentage))
5111 { /* Set gc_cons_combined_threshold. */
5112 EMACS_INT tot = 0;
5113
5114 tot += total_conses * sizeof (struct Lisp_Cons);
5115 tot += total_symbols * sizeof (struct Lisp_Symbol);
5116 tot += total_markers * sizeof (union Lisp_Misc);
5117 tot += total_string_size;
5118 tot += total_vector_size * sizeof (Lisp_Object);
5119 tot += total_floats * sizeof (struct Lisp_Float);
5120 tot += total_intervals * sizeof (struct interval);
5121 tot += total_strings * sizeof (struct Lisp_String);
5122
5123 gc_relative_threshold = tot * XFLOAT_DATA (Vgc_cons_percentage);
5124 }
5125 else
5126 gc_relative_threshold = 0;
5127
5128 if (garbage_collection_messages)
5129 {
5130 if (message_p || minibuf_level > 0)
5131 restore_message ();
5132 else
5133 message1_nolog ("Garbage collecting...done");
5134 }
5135
5136 unbind_to (count, Qnil);
5137
5138 total[0] = Fcons (make_number (total_conses),
5139 make_number (total_free_conses));
5140 total[1] = Fcons (make_number (total_symbols),
5141 make_number (total_free_symbols));
5142 total[2] = Fcons (make_number (total_markers),
5143 make_number (total_free_markers));
5144 total[3] = make_number (total_string_size);
5145 total[4] = make_number (total_vector_size);
5146 total[5] = Fcons (make_number (total_floats),
5147 make_number (total_free_floats));
5148 total[6] = Fcons (make_number (total_intervals),
5149 make_number (total_free_intervals));
5150 total[7] = Fcons (make_number (total_strings),
5151 make_number (total_free_strings));
5152
5153 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
5154 {
5155 /* Compute average percentage of zombies. */
5156 double nlive = 0;
5157
5158 for (i = 0; i < 7; ++i)
5159 if (CONSP (total[i]))
5160 nlive += XFASTINT (XCAR (total[i]));
5161
5162 avg_live = (avg_live * ngcs + nlive) / (ngcs + 1);
5163 max_live = max (nlive, max_live);
5164 avg_zombies = (avg_zombies * ngcs + nzombies) / (ngcs + 1);
5165 max_zombies = max (nzombies, max_zombies);
5166 ++ngcs;
5167 }
5168 #endif
5169
5170 if (!NILP (Vpost_gc_hook))
5171 {
5172 int gc_count = inhibit_garbage_collection ();
5173 safe_run_hooks (Qpost_gc_hook);
5174 unbind_to (gc_count, Qnil);
5175 }
5176
5177 /* Accumulate statistics. */
5178 EMACS_GET_TIME (t2);
5179 EMACS_SUB_TIME (t3, t2, t1);
5180 if (FLOATP (Vgc_elapsed))
5181 Vgc_elapsed = make_float (XFLOAT_DATA (Vgc_elapsed) +
5182 EMACS_SECS (t3) +
5183 EMACS_USECS (t3) * 1.0e-6);
5184 gcs_done++;
5185
5186 return Flist (sizeof total / sizeof *total, total);
5187 }
5188
5189
5190 /* Mark Lisp objects in glyph matrix MATRIX. Currently the
5191 only interesting objects referenced from glyphs are strings. */
5192
5193 static void
5194 mark_glyph_matrix (struct glyph_matrix *matrix)
5195 {
5196 struct glyph_row *row = matrix->rows;
5197 struct glyph_row *end = row + matrix->nrows;
5198
5199 for (; row < end; ++row)
5200 if (row->enabled_p)
5201 {
5202 int area;
5203 for (area = LEFT_MARGIN_AREA; area < LAST_AREA; ++area)
5204 {
5205 struct glyph *glyph = row->glyphs[area];
5206 struct glyph *end_glyph = glyph + row->used[area];
5207
5208 for (; glyph < end_glyph; ++glyph)
5209 if (STRINGP (glyph->object)
5210 && !STRING_MARKED_P (XSTRING (glyph->object)))
5211 mark_object (glyph->object);
5212 }
5213 }
5214 }
5215
5216
5217 /* Mark Lisp faces in the face cache C. */
5218
5219 static void
5220 mark_face_cache (struct face_cache *c)
5221 {
5222 if (c)
5223 {
5224 int i, j;
5225 for (i = 0; i < c->used; ++i)
5226 {
5227 struct face *face = FACE_FROM_ID (c->f, i);
5228
5229 if (face)
5230 {
5231 for (j = 0; j < LFACE_VECTOR_SIZE; ++j)
5232 mark_object (face->lface[j]);
5233 }
5234 }
5235 }
5236 }
5237
5238
5239 \f
5240 /* Mark reference to a Lisp_Object.
5241 If the object referred to has not been seen yet, recursively mark
5242 all the references contained in it. */
5243
5244 #define LAST_MARKED_SIZE 500
5245 static Lisp_Object last_marked[LAST_MARKED_SIZE];
5246 static int last_marked_index;
5247
5248 /* For debugging--call abort when we cdr down this many
5249 links of a list, in mark_object. In debugging,
5250 the call to abort will hit a breakpoint.
5251 Normally this is zero and the check never goes off. */
5252 static size_t mark_object_loop_halt;
5253
5254 static void
5255 mark_vectorlike (struct Lisp_Vector *ptr)
5256 {
5257 register EMACS_UINT size = ptr->header.size;
5258 register EMACS_UINT i;
5259
5260 eassert (!VECTOR_MARKED_P (ptr));
5261 VECTOR_MARK (ptr); /* Else mark it */
5262 if (size & PSEUDOVECTOR_FLAG)
5263 size &= PSEUDOVECTOR_SIZE_MASK;
5264
5265 /* Note that this size is not the memory-footprint size, but only
5266 the number of Lisp_Object fields that we should trace.
5267 The distinction is used e.g. by Lisp_Process which places extra
5268 non-Lisp_Object fields at the end of the structure. */
5269 for (i = 0; i < size; i++) /* and then mark its elements */
5270 mark_object (ptr->contents[i]);
5271 }
5272
5273 /* Like mark_vectorlike but optimized for char-tables (and
5274 sub-char-tables) assuming that the contents are mostly integers or
5275 symbols. */
5276
5277 static void
5278 mark_char_table (struct Lisp_Vector *ptr)
5279 {
5280 register EMACS_UINT size = ptr->header.size & PSEUDOVECTOR_SIZE_MASK;
5281 register EMACS_UINT i;
5282
5283 eassert (!VECTOR_MARKED_P (ptr));
5284 VECTOR_MARK (ptr);
5285 for (i = 0; i < size; i++)
5286 {
5287 Lisp_Object val = ptr->contents[i];
5288
5289 if (INTEGERP (val) || (SYMBOLP (val) && XSYMBOL (val)->gcmarkbit))
5290 continue;
5291 if (SUB_CHAR_TABLE_P (val))
5292 {
5293 if (! VECTOR_MARKED_P (XVECTOR (val)))
5294 mark_char_table (XVECTOR (val));
5295 }
5296 else
5297 mark_object (val);
5298 }
5299 }
5300
5301 void
5302 mark_object (Lisp_Object arg)
5303 {
5304 register Lisp_Object obj = arg;
5305 #ifdef GC_CHECK_MARKED_OBJECTS
5306 void *po;
5307 struct mem_node *m;
5308 #endif
5309 size_t cdr_count = 0;
5310
5311 loop:
5312
5313 if (PURE_POINTER_P (XPNTR (obj)))
5314 return;
5315
5316 last_marked[last_marked_index++] = obj;
5317 if (last_marked_index == LAST_MARKED_SIZE)
5318 last_marked_index = 0;
5319
5320 /* Perform some sanity checks on the objects marked here. Abort if
5321 we encounter an object we know is bogus. This increases GC time
5322 by ~80%, and requires compilation with GC_MARK_STACK != 0. */
5323 #ifdef GC_CHECK_MARKED_OBJECTS
5324
5325 po = (void *) XPNTR (obj);
5326
5327 /* Check that the object pointed to by PO is known to be a Lisp
5328 structure allocated from the heap. */
5329 #define CHECK_ALLOCATED() \
5330 do { \
5331 m = mem_find (po); \
5332 if (m == MEM_NIL) \
5333 abort (); \
5334 } while (0)
5335
5336 /* Check that the object pointed to by PO is live, using predicate
5337 function LIVEP. */
5338 #define CHECK_LIVE(LIVEP) \
5339 do { \
5340 if (!LIVEP (m, po)) \
5341 abort (); \
5342 } while (0)
5343
5344 /* Check both of the above conditions. */
5345 #define CHECK_ALLOCATED_AND_LIVE(LIVEP) \
5346 do { \
5347 CHECK_ALLOCATED (); \
5348 CHECK_LIVE (LIVEP); \
5349 } while (0) \
5350
5351 #else /* not GC_CHECK_MARKED_OBJECTS */
5352
5353 #define CHECK_LIVE(LIVEP) (void) 0
5354 #define CHECK_ALLOCATED_AND_LIVE(LIVEP) (void) 0
5355
5356 #endif /* not GC_CHECK_MARKED_OBJECTS */
5357
5358 switch (SWITCH_ENUM_CAST (XTYPE (obj)))
5359 {
5360 case Lisp_String:
5361 {
5362 register struct Lisp_String *ptr = XSTRING (obj);
5363 if (STRING_MARKED_P (ptr))
5364 break;
5365 CHECK_ALLOCATED_AND_LIVE (live_string_p);
5366 MARK_INTERVAL_TREE (ptr->intervals);
5367 MARK_STRING (ptr);
5368 #ifdef GC_CHECK_STRING_BYTES
5369 /* Check that the string size recorded in the string is the
5370 same as the one recorded in the sdata structure. */
5371 CHECK_STRING_BYTES (ptr);
5372 #endif /* GC_CHECK_STRING_BYTES */
5373 }
5374 break;
5375
5376 case Lisp_Vectorlike:
5377 if (VECTOR_MARKED_P (XVECTOR (obj)))
5378 break;
5379 #ifdef GC_CHECK_MARKED_OBJECTS
5380 m = mem_find (po);
5381 if (m == MEM_NIL && !SUBRP (obj)
5382 && po != &buffer_defaults
5383 && po != &buffer_local_symbols)
5384 abort ();
5385 #endif /* GC_CHECK_MARKED_OBJECTS */
5386
5387 if (BUFFERP (obj))
5388 {
5389 #ifdef GC_CHECK_MARKED_OBJECTS
5390 if (po != &buffer_defaults && po != &buffer_local_symbols)
5391 {
5392 struct buffer *b;
5393 for (b = all_buffers; b && b != po; b = b->header.next.buffer)
5394 ;
5395 if (b == NULL)
5396 abort ();
5397 }
5398 #endif /* GC_CHECK_MARKED_OBJECTS */
5399 mark_buffer (obj);
5400 }
5401 else if (SUBRP (obj))
5402 break;
5403 else if (COMPILEDP (obj))
5404 /* We could treat this just like a vector, but it is better to
5405 save the COMPILED_CONSTANTS element for last and avoid
5406 recursion there. */
5407 {
5408 register struct Lisp_Vector *ptr = XVECTOR (obj);
5409 register EMACS_UINT size = ptr->header.size;
5410 register EMACS_UINT i;
5411
5412 CHECK_LIVE (live_vector_p);
5413 VECTOR_MARK (ptr); /* Else mark it */
5414 size &= PSEUDOVECTOR_SIZE_MASK;
5415 for (i = 0; i < size; i++) /* and then mark its elements */
5416 {
5417 if (i != COMPILED_CONSTANTS)
5418 mark_object (ptr->contents[i]);
5419 }
5420 obj = ptr->contents[COMPILED_CONSTANTS];
5421 goto loop;
5422 }
5423 else if (FRAMEP (obj))
5424 {
5425 register struct frame *ptr = XFRAME (obj);
5426 mark_vectorlike (XVECTOR (obj));
5427 mark_face_cache (ptr->face_cache);
5428 }
5429 else if (WINDOWP (obj))
5430 {
5431 register struct Lisp_Vector *ptr = XVECTOR (obj);
5432 struct window *w = XWINDOW (obj);
5433 mark_vectorlike (ptr);
5434 /* Mark glyphs for leaf windows. Marking window matrices is
5435 sufficient because frame matrices use the same glyph
5436 memory. */
5437 if (NILP (w->hchild)
5438 && NILP (w->vchild)
5439 && w->current_matrix)
5440 {
5441 mark_glyph_matrix (w->current_matrix);
5442 mark_glyph_matrix (w->desired_matrix);
5443 }
5444 }
5445 else if (HASH_TABLE_P (obj))
5446 {
5447 struct Lisp_Hash_Table *h = XHASH_TABLE (obj);
5448 mark_vectorlike ((struct Lisp_Vector *)h);
5449 /* If hash table is not weak, mark all keys and values.
5450 For weak tables, mark only the vector. */
5451 if (NILP (h->weak))
5452 mark_object (h->key_and_value);
5453 else
5454 VECTOR_MARK (XVECTOR (h->key_and_value));
5455 }
5456 else if (CHAR_TABLE_P (obj))
5457 mark_char_table (XVECTOR (obj));
5458 else
5459 mark_vectorlike (XVECTOR (obj));
5460 break;
5461
5462 case Lisp_Symbol:
5463 {
5464 register struct Lisp_Symbol *ptr = XSYMBOL (obj);
5465 struct Lisp_Symbol *ptrx;
5466
5467 if (ptr->gcmarkbit)
5468 break;
5469 CHECK_ALLOCATED_AND_LIVE (live_symbol_p);
5470 ptr->gcmarkbit = 1;
5471 mark_object (ptr->function);
5472 mark_object (ptr->plist);
5473 switch (ptr->redirect)
5474 {
5475 case SYMBOL_PLAINVAL: mark_object (SYMBOL_VAL (ptr)); break;
5476 case SYMBOL_VARALIAS:
5477 {
5478 Lisp_Object tem;
5479 XSETSYMBOL (tem, SYMBOL_ALIAS (ptr));
5480 mark_object (tem);
5481 break;
5482 }
5483 case SYMBOL_LOCALIZED:
5484 {
5485 struct Lisp_Buffer_Local_Value *blv = SYMBOL_BLV (ptr);
5486 /* If the value is forwarded to a buffer or keyboard field,
5487 these are marked when we see the corresponding object.
5488 And if it's forwarded to a C variable, either it's not
5489 a Lisp_Object var, or it's staticpro'd already. */
5490 mark_object (blv->where);
5491 mark_object (blv->valcell);
5492 mark_object (blv->defcell);
5493 break;
5494 }
5495 case SYMBOL_FORWARDED:
5496 /* If the value is forwarded to a buffer or keyboard field,
5497 these are marked when we see the corresponding object.
5498 And if it's forwarded to a C variable, either it's not
5499 a Lisp_Object var, or it's staticpro'd already. */
5500 break;
5501 default: abort ();
5502 }
5503 if (!PURE_POINTER_P (XSTRING (ptr->xname)))
5504 MARK_STRING (XSTRING (ptr->xname));
5505 MARK_INTERVAL_TREE (STRING_INTERVALS (ptr->xname));
5506
5507 ptr = ptr->next;
5508 if (ptr)
5509 {
5510 ptrx = ptr; /* Use of ptrx avoids compiler bug on Sun */
5511 XSETSYMBOL (obj, ptrx);
5512 goto loop;
5513 }
5514 }
5515 break;
5516
5517 case Lisp_Misc:
5518 CHECK_ALLOCATED_AND_LIVE (live_misc_p);
5519 if (XMISCANY (obj)->gcmarkbit)
5520 break;
5521 XMISCANY (obj)->gcmarkbit = 1;
5522
5523 switch (XMISCTYPE (obj))
5524 {
5525
5526 case Lisp_Misc_Marker:
5527 /* DO NOT mark thru the marker's chain.
5528 The buffer's markers chain does not preserve markers from gc;
5529 instead, markers are removed from the chain when freed by gc. */
5530 break;
5531
5532 case Lisp_Misc_Save_Value:
5533 #if GC_MARK_STACK
5534 {
5535 register struct Lisp_Save_Value *ptr = XSAVE_VALUE (obj);
5536 /* If DOGC is set, POINTER is the address of a memory
5537 area containing INTEGER potential Lisp_Objects. */
5538 if (ptr->dogc)
5539 {
5540 Lisp_Object *p = (Lisp_Object *) ptr->pointer;
5541 int nelt;
5542 for (nelt = ptr->integer; nelt > 0; nelt--, p++)
5543 mark_maybe_object (*p);
5544 }
5545 }
5546 #endif
5547 break;
5548
5549 case Lisp_Misc_Overlay:
5550 {
5551 struct Lisp_Overlay *ptr = XOVERLAY (obj);
5552 mark_object (ptr->start);
5553 mark_object (ptr->end);
5554 mark_object (ptr->plist);
5555 if (ptr->next)
5556 {
5557 XSETMISC (obj, ptr->next);
5558 goto loop;
5559 }
5560 }
5561 break;
5562
5563 default:
5564 abort ();
5565 }
5566 break;
5567
5568 case Lisp_Cons:
5569 {
5570 register struct Lisp_Cons *ptr = XCONS (obj);
5571 if (CONS_MARKED_P (ptr))
5572 break;
5573 CHECK_ALLOCATED_AND_LIVE (live_cons_p);
5574 CONS_MARK (ptr);
5575 /* If the cdr is nil, avoid recursion for the car. */
5576 if (EQ (ptr->u.cdr, Qnil))
5577 {
5578 obj = ptr->car;
5579 cdr_count = 0;
5580 goto loop;
5581 }
5582 mark_object (ptr->car);
5583 obj = ptr->u.cdr;
5584 cdr_count++;
5585 if (cdr_count == mark_object_loop_halt)
5586 abort ();
5587 goto loop;
5588 }
5589
5590 case Lisp_Float:
5591 CHECK_ALLOCATED_AND_LIVE (live_float_p);
5592 FLOAT_MARK (XFLOAT (obj));
5593 break;
5594
5595 case_Lisp_Int:
5596 break;
5597
5598 default:
5599 abort ();
5600 }
5601
5602 #undef CHECK_LIVE
5603 #undef CHECK_ALLOCATED
5604 #undef CHECK_ALLOCATED_AND_LIVE
5605 }
5606
5607 /* Mark the pointers in a buffer structure. */
5608
5609 static void
5610 mark_buffer (Lisp_Object buf)
5611 {
5612 register struct buffer *buffer = XBUFFER (buf);
5613 register Lisp_Object *ptr, tmp;
5614 Lisp_Object base_buffer;
5615
5616 eassert (!VECTOR_MARKED_P (buffer));
5617 VECTOR_MARK (buffer);
5618
5619 MARK_INTERVAL_TREE (BUF_INTERVALS (buffer));
5620
5621 /* For now, we just don't mark the undo_list. It's done later in
5622 a special way just before the sweep phase, and after stripping
5623 some of its elements that are not needed any more. */
5624
5625 if (buffer->overlays_before)
5626 {
5627 XSETMISC (tmp, buffer->overlays_before);
5628 mark_object (tmp);
5629 }
5630 if (buffer->overlays_after)
5631 {
5632 XSETMISC (tmp, buffer->overlays_after);
5633 mark_object (tmp);
5634 }
5635
5636 /* buffer-local Lisp variables start at `undo_list',
5637 tho only the ones from `name' on are GC'd normally. */
5638 for (ptr = &buffer->BUFFER_INTERNAL_FIELD (name);
5639 (char *)ptr < (char *)buffer + sizeof (struct buffer);
5640 ptr++)
5641 mark_object (*ptr);
5642
5643 /* If this is an indirect buffer, mark its base buffer. */
5644 if (buffer->base_buffer && !VECTOR_MARKED_P (buffer->base_buffer))
5645 {
5646 XSETBUFFER (base_buffer, buffer->base_buffer);
5647 mark_buffer (base_buffer);
5648 }
5649 }
5650
5651 /* Mark the Lisp pointers in the terminal objects.
5652 Called by the Fgarbage_collector. */
5653
5654 static void
5655 mark_terminals (void)
5656 {
5657 struct terminal *t;
5658 for (t = terminal_list; t; t = t->next_terminal)
5659 {
5660 eassert (t->name != NULL);
5661 #ifdef HAVE_WINDOW_SYSTEM
5662 /* If a terminal object is reachable from a stacpro'ed object,
5663 it might have been marked already. Make sure the image cache
5664 gets marked. */
5665 mark_image_cache (t->image_cache);
5666 #endif /* HAVE_WINDOW_SYSTEM */
5667 if (!VECTOR_MARKED_P (t))
5668 mark_vectorlike ((struct Lisp_Vector *)t);
5669 }
5670 }
5671
5672
5673
5674 /* Value is non-zero if OBJ will survive the current GC because it's
5675 either marked or does not need to be marked to survive. */
5676
5677 int
5678 survives_gc_p (Lisp_Object obj)
5679 {
5680 int survives_p;
5681
5682 switch (XTYPE (obj))
5683 {
5684 case_Lisp_Int:
5685 survives_p = 1;
5686 break;
5687
5688 case Lisp_Symbol:
5689 survives_p = XSYMBOL (obj)->gcmarkbit;
5690 break;
5691
5692 case Lisp_Misc:
5693 survives_p = XMISCANY (obj)->gcmarkbit;
5694 break;
5695
5696 case Lisp_String:
5697 survives_p = STRING_MARKED_P (XSTRING (obj));
5698 break;
5699
5700 case Lisp_Vectorlike:
5701 survives_p = SUBRP (obj) || VECTOR_MARKED_P (XVECTOR (obj));
5702 break;
5703
5704 case Lisp_Cons:
5705 survives_p = CONS_MARKED_P (XCONS (obj));
5706 break;
5707
5708 case Lisp_Float:
5709 survives_p = FLOAT_MARKED_P (XFLOAT (obj));
5710 break;
5711
5712 default:
5713 abort ();
5714 }
5715
5716 return survives_p || PURE_POINTER_P ((void *) XPNTR (obj));
5717 }
5718
5719
5720 \f
5721 /* Sweep: find all structures not marked, and free them. */
5722
5723 static void
5724 gc_sweep (void)
5725 {
5726 /* Remove or mark entries in weak hash tables.
5727 This must be done before any object is unmarked. */
5728 sweep_weak_hash_tables ();
5729
5730 sweep_strings ();
5731 #ifdef GC_CHECK_STRING_BYTES
5732 if (!noninteractive)
5733 check_string_bytes (1);
5734 #endif
5735
5736 /* Put all unmarked conses on free list */
5737 {
5738 register struct cons_block *cblk;
5739 struct cons_block **cprev = &cons_block;
5740 register int lim = cons_block_index;
5741 register int num_free = 0, num_used = 0;
5742
5743 cons_free_list = 0;
5744
5745 for (cblk = cons_block; cblk; cblk = *cprev)
5746 {
5747 register int i = 0;
5748 int this_free = 0;
5749 int ilim = (lim + BITS_PER_INT - 1) / BITS_PER_INT;
5750
5751 /* Scan the mark bits an int at a time. */
5752 for (i = 0; i <= ilim; i++)
5753 {
5754 if (cblk->gcmarkbits[i] == -1)
5755 {
5756 /* Fast path - all cons cells for this int are marked. */
5757 cblk->gcmarkbits[i] = 0;
5758 num_used += BITS_PER_INT;
5759 }
5760 else
5761 {
5762 /* Some cons cells for this int are not marked.
5763 Find which ones, and free them. */
5764 int start, pos, stop;
5765
5766 start = i * BITS_PER_INT;
5767 stop = lim - start;
5768 if (stop > BITS_PER_INT)
5769 stop = BITS_PER_INT;
5770 stop += start;
5771
5772 for (pos = start; pos < stop; pos++)
5773 {
5774 if (!CONS_MARKED_P (&cblk->conses[pos]))
5775 {
5776 this_free++;
5777 cblk->conses[pos].u.chain = cons_free_list;
5778 cons_free_list = &cblk->conses[pos];
5779 #if GC_MARK_STACK
5780 cons_free_list->car = Vdead;
5781 #endif
5782 }
5783 else
5784 {
5785 num_used++;
5786 CONS_UNMARK (&cblk->conses[pos]);
5787 }
5788 }
5789 }
5790 }
5791
5792 lim = CONS_BLOCK_SIZE;
5793 /* If this block contains only free conses and we have already
5794 seen more than two blocks worth of free conses then deallocate
5795 this block. */
5796 if (this_free == CONS_BLOCK_SIZE && num_free > CONS_BLOCK_SIZE)
5797 {
5798 *cprev = cblk->next;
5799 /* Unhook from the free list. */
5800 cons_free_list = cblk->conses[0].u.chain;
5801 lisp_align_free (cblk);
5802 n_cons_blocks--;
5803 }
5804 else
5805 {
5806 num_free += this_free;
5807 cprev = &cblk->next;
5808 }
5809 }
5810 total_conses = num_used;
5811 total_free_conses = num_free;
5812 }
5813
5814 /* Put all unmarked floats on free list */
5815 {
5816 register struct float_block *fblk;
5817 struct float_block **fprev = &float_block;
5818 register int lim = float_block_index;
5819 register int num_free = 0, num_used = 0;
5820
5821 float_free_list = 0;
5822
5823 for (fblk = float_block; fblk; fblk = *fprev)
5824 {
5825 register int i;
5826 int this_free = 0;
5827 for (i = 0; i < lim; i++)
5828 if (!FLOAT_MARKED_P (&fblk->floats[i]))
5829 {
5830 this_free++;
5831 fblk->floats[i].u.chain = float_free_list;
5832 float_free_list = &fblk->floats[i];
5833 }
5834 else
5835 {
5836 num_used++;
5837 FLOAT_UNMARK (&fblk->floats[i]);
5838 }
5839 lim = FLOAT_BLOCK_SIZE;
5840 /* If this block contains only free floats and we have already
5841 seen more than two blocks worth of free floats then deallocate
5842 this block. */
5843 if (this_free == FLOAT_BLOCK_SIZE && num_free > FLOAT_BLOCK_SIZE)
5844 {
5845 *fprev = fblk->next;
5846 /* Unhook from the free list. */
5847 float_free_list = fblk->floats[0].u.chain;
5848 lisp_align_free (fblk);
5849 n_float_blocks--;
5850 }
5851 else
5852 {
5853 num_free += this_free;
5854 fprev = &fblk->next;
5855 }
5856 }
5857 total_floats = num_used;
5858 total_free_floats = num_free;
5859 }
5860
5861 /* Put all unmarked intervals on free list */
5862 {
5863 register struct interval_block *iblk;
5864 struct interval_block **iprev = &interval_block;
5865 register int lim = interval_block_index;
5866 register int num_free = 0, num_used = 0;
5867
5868 interval_free_list = 0;
5869
5870 for (iblk = interval_block; iblk; iblk = *iprev)
5871 {
5872 register int i;
5873 int this_free = 0;
5874
5875 for (i = 0; i < lim; i++)
5876 {
5877 if (!iblk->intervals[i].gcmarkbit)
5878 {
5879 SET_INTERVAL_PARENT (&iblk->intervals[i], interval_free_list);
5880 interval_free_list = &iblk->intervals[i];
5881 this_free++;
5882 }
5883 else
5884 {
5885 num_used++;
5886 iblk->intervals[i].gcmarkbit = 0;
5887 }
5888 }
5889 lim = INTERVAL_BLOCK_SIZE;
5890 /* If this block contains only free intervals and we have already
5891 seen more than two blocks worth of free intervals then
5892 deallocate this block. */
5893 if (this_free == INTERVAL_BLOCK_SIZE && num_free > INTERVAL_BLOCK_SIZE)
5894 {
5895 *iprev = iblk->next;
5896 /* Unhook from the free list. */
5897 interval_free_list = INTERVAL_PARENT (&iblk->intervals[0]);
5898 lisp_free (iblk);
5899 n_interval_blocks--;
5900 }
5901 else
5902 {
5903 num_free += this_free;
5904 iprev = &iblk->next;
5905 }
5906 }
5907 total_intervals = num_used;
5908 total_free_intervals = num_free;
5909 }
5910
5911 /* Put all unmarked symbols on free list */
5912 {
5913 register struct symbol_block *sblk;
5914 struct symbol_block **sprev = &symbol_block;
5915 register int lim = symbol_block_index;
5916 register int num_free = 0, num_used = 0;
5917
5918 symbol_free_list = NULL;
5919
5920 for (sblk = symbol_block; sblk; sblk = *sprev)
5921 {
5922 int this_free = 0;
5923 struct Lisp_Symbol *sym = sblk->symbols;
5924 struct Lisp_Symbol *end = sym + lim;
5925
5926 for (; sym < end; ++sym)
5927 {
5928 /* Check if the symbol was created during loadup. In such a case
5929 it might be pointed to by pure bytecode which we don't trace,
5930 so we conservatively assume that it is live. */
5931 int pure_p = PURE_POINTER_P (XSTRING (sym->xname));
5932
5933 if (!sym->gcmarkbit && !pure_p)
5934 {
5935 if (sym->redirect == SYMBOL_LOCALIZED)
5936 xfree (SYMBOL_BLV (sym));
5937 sym->next = symbol_free_list;
5938 symbol_free_list = sym;
5939 #if GC_MARK_STACK
5940 symbol_free_list->function = Vdead;
5941 #endif
5942 ++this_free;
5943 }
5944 else
5945 {
5946 ++num_used;
5947 if (!pure_p)
5948 UNMARK_STRING (XSTRING (sym->xname));
5949 sym->gcmarkbit = 0;
5950 }
5951 }
5952
5953 lim = SYMBOL_BLOCK_SIZE;
5954 /* If this block contains only free symbols and we have already
5955 seen more than two blocks worth of free symbols then deallocate
5956 this block. */
5957 if (this_free == SYMBOL_BLOCK_SIZE && num_free > SYMBOL_BLOCK_SIZE)
5958 {
5959 *sprev = sblk->next;
5960 /* Unhook from the free list. */
5961 symbol_free_list = sblk->symbols[0].next;
5962 lisp_free (sblk);
5963 n_symbol_blocks--;
5964 }
5965 else
5966 {
5967 num_free += this_free;
5968 sprev = &sblk->next;
5969 }
5970 }
5971 total_symbols = num_used;
5972 total_free_symbols = num_free;
5973 }
5974
5975 /* Put all unmarked misc's on free list.
5976 For a marker, first unchain it from the buffer it points into. */
5977 {
5978 register struct marker_block *mblk;
5979 struct marker_block **mprev = &marker_block;
5980 register int lim = marker_block_index;
5981 register int num_free = 0, num_used = 0;
5982
5983 marker_free_list = 0;
5984
5985 for (mblk = marker_block; mblk; mblk = *mprev)
5986 {
5987 register int i;
5988 int this_free = 0;
5989
5990 for (i = 0; i < lim; i++)
5991 {
5992 if (!mblk->markers[i].u_any.gcmarkbit)
5993 {
5994 if (mblk->markers[i].u_any.type == Lisp_Misc_Marker)
5995 unchain_marker (&mblk->markers[i].u_marker);
5996 /* Set the type of the freed object to Lisp_Misc_Free.
5997 We could leave the type alone, since nobody checks it,
5998 but this might catch bugs faster. */
5999 mblk->markers[i].u_marker.type = Lisp_Misc_Free;
6000 mblk->markers[i].u_free.chain = marker_free_list;
6001 marker_free_list = &mblk->markers[i];
6002 this_free++;
6003 }
6004 else
6005 {
6006 num_used++;
6007 mblk->markers[i].u_any.gcmarkbit = 0;
6008 }
6009 }
6010 lim = MARKER_BLOCK_SIZE;
6011 /* If this block contains only free markers and we have already
6012 seen more than two blocks worth of free markers then deallocate
6013 this block. */
6014 if (this_free == MARKER_BLOCK_SIZE && num_free > MARKER_BLOCK_SIZE)
6015 {
6016 *mprev = mblk->next;
6017 /* Unhook from the free list. */
6018 marker_free_list = mblk->markers[0].u_free.chain;
6019 lisp_free (mblk);
6020 n_marker_blocks--;
6021 }
6022 else
6023 {
6024 num_free += this_free;
6025 mprev = &mblk->next;
6026 }
6027 }
6028
6029 total_markers = num_used;
6030 total_free_markers = num_free;
6031 }
6032
6033 /* Free all unmarked buffers */
6034 {
6035 register struct buffer *buffer = all_buffers, *prev = 0, *next;
6036
6037 while (buffer)
6038 if (!VECTOR_MARKED_P (buffer))
6039 {
6040 if (prev)
6041 prev->header.next = buffer->header.next;
6042 else
6043 all_buffers = buffer->header.next.buffer;
6044 next = buffer->header.next.buffer;
6045 lisp_free (buffer);
6046 buffer = next;
6047 }
6048 else
6049 {
6050 VECTOR_UNMARK (buffer);
6051 UNMARK_BALANCE_INTERVALS (BUF_INTERVALS (buffer));
6052 prev = buffer, buffer = buffer->header.next.buffer;
6053 }
6054 }
6055
6056 /* Free all unmarked vectors */
6057 {
6058 register struct Lisp_Vector *vector = all_vectors, *prev = 0, *next;
6059 total_vector_size = 0;
6060
6061 while (vector)
6062 if (!VECTOR_MARKED_P (vector))
6063 {
6064 if (prev)
6065 prev->header.next = vector->header.next;
6066 else
6067 all_vectors = vector->header.next.vector;
6068 next = vector->header.next.vector;
6069 lisp_free (vector);
6070 n_vectors--;
6071 vector = next;
6072
6073 }
6074 else
6075 {
6076 VECTOR_UNMARK (vector);
6077 if (vector->header.size & PSEUDOVECTOR_FLAG)
6078 total_vector_size += PSEUDOVECTOR_SIZE_MASK & vector->header.size;
6079 else
6080 total_vector_size += vector->header.size;
6081 prev = vector, vector = vector->header.next.vector;
6082 }
6083 }
6084
6085 #ifdef GC_CHECK_STRING_BYTES
6086 if (!noninteractive)
6087 check_string_bytes (1);
6088 #endif
6089 }
6090
6091
6092
6093 \f
6094 /* Debugging aids. */
6095
6096 DEFUN ("memory-limit", Fmemory_limit, Smemory_limit, 0, 0, 0,
6097 doc: /* Return the address of the last byte Emacs has allocated, divided by 1024.
6098 This may be helpful in debugging Emacs's memory usage.
6099 We divide the value by 1024 to make sure it fits in a Lisp integer. */)
6100 (void)
6101 {
6102 Lisp_Object end;
6103
6104 XSETINT (end, (intptr_t) (char *) sbrk (0) / 1024);
6105
6106 return end;
6107 }
6108
6109 DEFUN ("memory-use-counts", Fmemory_use_counts, Smemory_use_counts, 0, 0, 0,
6110 doc: /* Return a list of counters that measure how much consing there has been.
6111 Each of these counters increments for a certain kind of object.
6112 The counters wrap around from the largest positive integer to zero.
6113 Garbage collection does not decrease them.
6114 The elements of the value are as follows:
6115 (CONSES FLOATS VECTOR-CELLS SYMBOLS STRING-CHARS MISCS INTERVALS STRINGS)
6116 All are in units of 1 = one object consed
6117 except for VECTOR-CELLS and STRING-CHARS, which count the total length of
6118 objects consed.
6119 MISCS include overlays, markers, and some internal types.
6120 Frames, windows, buffers, and subprocesses count as vectors
6121 (but the contents of a buffer's text do not count here). */)
6122 (void)
6123 {
6124 Lisp_Object consed[8];
6125
6126 consed[0] = make_number (min (MOST_POSITIVE_FIXNUM, cons_cells_consed));
6127 consed[1] = make_number (min (MOST_POSITIVE_FIXNUM, floats_consed));
6128 consed[2] = make_number (min (MOST_POSITIVE_FIXNUM, vector_cells_consed));
6129 consed[3] = make_number (min (MOST_POSITIVE_FIXNUM, symbols_consed));
6130 consed[4] = make_number (min (MOST_POSITIVE_FIXNUM, string_chars_consed));
6131 consed[5] = make_number (min (MOST_POSITIVE_FIXNUM, misc_objects_consed));
6132 consed[6] = make_number (min (MOST_POSITIVE_FIXNUM, intervals_consed));
6133 consed[7] = make_number (min (MOST_POSITIVE_FIXNUM, strings_consed));
6134
6135 return Flist (8, consed);
6136 }
6137
6138 #ifdef ENABLE_CHECKING
6139 int suppress_checking;
6140
6141 void
6142 die (const char *msg, const char *file, int line)
6143 {
6144 fprintf (stderr, "\r\n%s:%d: Emacs fatal error: %s\r\n",
6145 file, line, msg);
6146 abort ();
6147 }
6148 #endif
6149 \f
6150 /* Initialization */
6151
6152 void
6153 init_alloc_once (void)
6154 {
6155 /* Used to do Vpurify_flag = Qt here, but Qt isn't set up yet! */
6156 purebeg = PUREBEG;
6157 pure_size = PURESIZE;
6158 pure_bytes_used = 0;
6159 pure_bytes_used_lisp = pure_bytes_used_non_lisp = 0;
6160 pure_bytes_used_before_overflow = 0;
6161
6162 /* Initialize the list of free aligned blocks. */
6163 free_ablock = NULL;
6164
6165 #if GC_MARK_STACK || defined GC_MALLOC_CHECK
6166 mem_init ();
6167 Vdead = make_pure_string ("DEAD", 4, 4, 0);
6168 #endif
6169
6170 all_vectors = 0;
6171 ignore_warnings = 1;
6172 #ifdef DOUG_LEA_MALLOC
6173 mallopt (M_TRIM_THRESHOLD, 128*1024); /* trim threshold */
6174 mallopt (M_MMAP_THRESHOLD, 64*1024); /* mmap threshold */
6175 mallopt (M_MMAP_MAX, MMAP_MAX_AREAS); /* max. number of mmap'ed areas */
6176 #endif
6177 init_strings ();
6178 init_cons ();
6179 init_symbol ();
6180 init_marker ();
6181 init_float ();
6182 init_intervals ();
6183 init_weak_hash_tables ();
6184
6185 #ifdef REL_ALLOC
6186 malloc_hysteresis = 32;
6187 #else
6188 malloc_hysteresis = 0;
6189 #endif
6190
6191 refill_memory_reserve ();
6192
6193 ignore_warnings = 0;
6194 gcprolist = 0;
6195 byte_stack_list = 0;
6196 staticidx = 0;
6197 consing_since_gc = 0;
6198 gc_cons_threshold = 100000 * sizeof (Lisp_Object);
6199 gc_relative_threshold = 0;
6200 }
6201
6202 void
6203 init_alloc (void)
6204 {
6205 gcprolist = 0;
6206 byte_stack_list = 0;
6207 #if GC_MARK_STACK
6208 #if !defined GC_SAVE_REGISTERS_ON_STACK && !defined GC_SETJMP_WORKS
6209 setjmp_tested_p = longjmps_done = 0;
6210 #endif
6211 #endif
6212 Vgc_elapsed = make_float (0.0);
6213 gcs_done = 0;
6214 }
6215
6216 void
6217 syms_of_alloc (void)
6218 {
6219 DEFVAR_INT ("gc-cons-threshold", gc_cons_threshold,
6220 doc: /* *Number of bytes of consing between garbage collections.
6221 Garbage collection can happen automatically once this many bytes have been
6222 allocated since the last garbage collection. All data types count.
6223
6224 Garbage collection happens automatically only when `eval' is called.
6225
6226 By binding this temporarily to a large number, you can effectively
6227 prevent garbage collection during a part of the program.
6228 See also `gc-cons-percentage'. */);
6229
6230 DEFVAR_LISP ("gc-cons-percentage", Vgc_cons_percentage,
6231 doc: /* *Portion of the heap used for allocation.
6232 Garbage collection can happen automatically once this portion of the heap
6233 has been allocated since the last garbage collection.
6234 If this portion is smaller than `gc-cons-threshold', this is ignored. */);
6235 Vgc_cons_percentage = make_float (0.1);
6236
6237 DEFVAR_INT ("pure-bytes-used", pure_bytes_used,
6238 doc: /* Number of bytes of sharable Lisp data allocated so far. */);
6239
6240 DEFVAR_INT ("cons-cells-consed", cons_cells_consed,
6241 doc: /* Number of cons cells that have been consed so far. */);
6242
6243 DEFVAR_INT ("floats-consed", floats_consed,
6244 doc: /* Number of floats that have been consed so far. */);
6245
6246 DEFVAR_INT ("vector-cells-consed", vector_cells_consed,
6247 doc: /* Number of vector cells that have been consed so far. */);
6248
6249 DEFVAR_INT ("symbols-consed", symbols_consed,
6250 doc: /* Number of symbols that have been consed so far. */);
6251
6252 DEFVAR_INT ("string-chars-consed", string_chars_consed,
6253 doc: /* Number of string characters that have been consed so far. */);
6254
6255 DEFVAR_INT ("misc-objects-consed", misc_objects_consed,
6256 doc: /* Number of miscellaneous objects that have been consed so far. */);
6257
6258 DEFVAR_INT ("intervals-consed", intervals_consed,
6259 doc: /* Number of intervals that have been consed so far. */);
6260
6261 DEFVAR_INT ("strings-consed", strings_consed,
6262 doc: /* Number of strings that have been consed so far. */);
6263
6264 DEFVAR_LISP ("purify-flag", Vpurify_flag,
6265 doc: /* Non-nil means loading Lisp code in order to dump an executable.
6266 This means that certain objects should be allocated in shared (pure) space.
6267 It can also be set to a hash-table, in which case this table is used to
6268 do hash-consing of the objects allocated to pure space. */);
6269
6270 DEFVAR_BOOL ("garbage-collection-messages", garbage_collection_messages,
6271 doc: /* Non-nil means display messages at start and end of garbage collection. */);
6272 garbage_collection_messages = 0;
6273
6274 DEFVAR_LISP ("post-gc-hook", Vpost_gc_hook,
6275 doc: /* Hook run after garbage collection has finished. */);
6276 Vpost_gc_hook = Qnil;
6277 Qpost_gc_hook = intern_c_string ("post-gc-hook");
6278 staticpro (&Qpost_gc_hook);
6279
6280 DEFVAR_LISP ("memory-signal-data", Vmemory_signal_data,
6281 doc: /* Precomputed `signal' argument for memory-full error. */);
6282 /* We build this in advance because if we wait until we need it, we might
6283 not be able to allocate the memory to hold it. */
6284 Vmemory_signal_data
6285 = pure_cons (Qerror,
6286 pure_cons (make_pure_c_string ("Memory exhausted--use M-x save-some-buffers then exit and restart Emacs"), Qnil));
6287
6288 DEFVAR_LISP ("memory-full", Vmemory_full,
6289 doc: /* Non-nil means Emacs cannot get much more Lisp memory. */);
6290 Vmemory_full = Qnil;
6291
6292 staticpro (&Qgc_cons_threshold);
6293 Qgc_cons_threshold = intern_c_string ("gc-cons-threshold");
6294
6295 staticpro (&Qchar_table_extra_slots);
6296 Qchar_table_extra_slots = intern_c_string ("char-table-extra-slots");
6297
6298 DEFVAR_LISP ("gc-elapsed", Vgc_elapsed,
6299 doc: /* Accumulated time elapsed in garbage collections.
6300 The time is in seconds as a floating point value. */);
6301 DEFVAR_INT ("gcs-done", gcs_done,
6302 doc: /* Accumulated number of garbage collections done. */);
6303
6304 defsubr (&Scons);
6305 defsubr (&Slist);
6306 defsubr (&Svector);
6307 defsubr (&Smake_byte_code);
6308 defsubr (&Smake_list);
6309 defsubr (&Smake_vector);
6310 defsubr (&Smake_string);
6311 defsubr (&Smake_bool_vector);
6312 defsubr (&Smake_symbol);
6313 defsubr (&Smake_marker);
6314 defsubr (&Spurecopy);
6315 defsubr (&Sgarbage_collect);
6316 defsubr (&Smemory_limit);
6317 defsubr (&Smemory_use_counts);
6318
6319 #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES
6320 defsubr (&Sgc_status);
6321 #endif
6322 }