Some improvements in vc
[emacs.git] / src / alloc.c
blobc5a4f425f6e2b826635c1a78cc6bf3683a3506f5
1 /* Storage allocation and gc for GNU Emacs Lisp interpreter.
3 Copyright (C) 1985-1986, 1988, 1993-1995, 1997-2016 Free Software
4 Foundation, Inc.
6 This file is part of GNU Emacs.
8 GNU Emacs is free software: you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation, either version 3 of the License, or (at
11 your option) any later version.
13 GNU Emacs is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */
21 #include <config.h>
23 #include <stdio.h>
24 #include <limits.h> /* For CHAR_BIT. */
25 #include <signal.h> /* For SIGABRT, SIGDANGER. */
27 #ifdef HAVE_PTHREAD
28 #include <pthread.h>
29 #endif
31 #include "lisp.h"
32 #include "dispextern.h"
33 #include "intervals.h"
34 #include "puresize.h"
35 #include "sheap.h"
36 #include "systime.h"
37 #include "character.h"
38 #include "buffer.h"
39 #include "window.h"
40 #include "keyboard.h"
41 #include "frame.h"
42 #include "blockinput.h"
43 #include "termhooks.h" /* For struct terminal. */
44 #ifdef HAVE_WINDOW_SYSTEM
45 #include TERM_HEADER
46 #endif /* HAVE_WINDOW_SYSTEM */
48 #include <verify.h>
49 #include <execinfo.h> /* For backtrace. */
51 #ifdef HAVE_LINUX_SYSINFO
52 #include <sys/sysinfo.h>
53 #endif
55 #ifdef MSDOS
56 #include "dosfns.h" /* For dos_memory_info. */
57 #endif
59 #ifdef HAVE_MALLOC_H
60 # include <malloc.h>
61 #endif
63 #if (defined ENABLE_CHECKING \
64 && defined HAVE_VALGRIND_VALGRIND_H \
65 && !defined USE_VALGRIND)
66 # define USE_VALGRIND 1
67 #endif
69 #if USE_VALGRIND
70 #include <valgrind/valgrind.h>
71 #include <valgrind/memcheck.h>
72 static bool valgrind_p;
73 #endif
75 /* GC_CHECK_MARKED_OBJECTS means do sanity checks on allocated objects. */
77 /* GC_MALLOC_CHECK defined means perform validity checks of malloc'd
78 memory. Can do this only if using gmalloc.c and if not checking
79 marked objects. */
81 #if (defined SYSTEM_MALLOC || defined DOUG_LEA_MALLOC \
82 || defined HYBRID_MALLOC || defined GC_CHECK_MARKED_OBJECTS)
83 #undef GC_MALLOC_CHECK
84 #endif
86 #include <unistd.h>
87 #include <fcntl.h>
89 #ifdef USE_GTK
90 # include "gtkutil.h"
91 #endif
92 #ifdef WINDOWSNT
93 #include "w32.h"
94 #include "w32heap.h" /* for sbrk */
95 #endif
97 #if defined DOUG_LEA_MALLOC || defined GNU_LINUX
98 /* The address where the heap starts. */
99 void *
100 my_heap_start (void)
102 static void *start;
103 if (! start)
104 start = sbrk (0);
105 return start;
107 #endif
109 #ifdef DOUG_LEA_MALLOC
111 /* Specify maximum number of areas to mmap. It would be nice to use a
112 value that explicitly means "no limit". */
114 #define MMAP_MAX_AREAS 100000000
116 /* A pointer to the memory allocated that copies that static data
117 inside glibc's malloc. */
118 static void *malloc_state_ptr;
120 /* Restore the dumped malloc state. Because malloc can be invoked
121 even before main (e.g. by the dynamic linker), the dumped malloc
122 state must be restored as early as possible using this special hook. */
123 static void
124 malloc_initialize_hook (void)
126 static bool malloc_using_checking;
128 if (! initialized)
130 my_heap_start ();
131 malloc_using_checking = getenv ("MALLOC_CHECK_") != NULL;
133 else
135 if (!malloc_using_checking)
137 /* Work around a bug in glibc's malloc. MALLOC_CHECK_ must be
138 ignored if the heap to be restored was constructed without
139 malloc checking. Can't use unsetenv, since that calls malloc. */
140 char **p = environ;
141 if (p)
142 for (; *p; p++)
143 if (strncmp (*p, "MALLOC_CHECK_=", 14) == 0)
146 *p = p[1];
147 while (*++p);
149 break;
153 malloc_set_state (malloc_state_ptr);
154 # ifndef XMALLOC_OVERRUN_CHECK
155 alloc_unexec_post ();
156 # endif
160 /* Declare the malloc initialization hook, which runs before 'main' starts.
161 EXTERNALLY_VISIBLE works around Bug#22522. */
162 # ifndef __MALLOC_HOOK_VOLATILE
163 # define __MALLOC_HOOK_VOLATILE
164 # endif
165 voidfuncptr __MALLOC_HOOK_VOLATILE __malloc_initialize_hook EXTERNALLY_VISIBLE
166 = malloc_initialize_hook;
168 #endif
170 /* Allocator-related actions to do just before and after unexec. */
172 void
173 alloc_unexec_pre (void)
175 #ifdef DOUG_LEA_MALLOC
176 malloc_state_ptr = malloc_get_state ();
177 #endif
178 #ifdef HYBRID_MALLOC
179 bss_sbrk_did_unexec = true;
180 #endif
183 void
184 alloc_unexec_post (void)
186 #ifdef DOUG_LEA_MALLOC
187 free (malloc_state_ptr);
188 #endif
189 #ifdef HYBRID_MALLOC
190 bss_sbrk_did_unexec = false;
191 #endif
194 /* Mark, unmark, query mark bit of a Lisp string. S must be a pointer
195 to a struct Lisp_String. */
197 #define MARK_STRING(S) ((S)->size |= ARRAY_MARK_FLAG)
198 #define UNMARK_STRING(S) ((S)->size &= ~ARRAY_MARK_FLAG)
199 #define STRING_MARKED_P(S) (((S)->size & ARRAY_MARK_FLAG) != 0)
201 #define VECTOR_MARK(V) ((V)->header.size |= ARRAY_MARK_FLAG)
202 #define VECTOR_UNMARK(V) ((V)->header.size &= ~ARRAY_MARK_FLAG)
203 #define VECTOR_MARKED_P(V) (((V)->header.size & ARRAY_MARK_FLAG) != 0)
205 /* Default value of gc_cons_threshold (see below). */
207 #define GC_DEFAULT_THRESHOLD (100000 * word_size)
209 /* Global variables. */
210 struct emacs_globals globals;
212 /* Number of bytes of consing done since the last gc. */
214 EMACS_INT consing_since_gc;
216 /* Similar minimum, computed from Vgc_cons_percentage. */
218 EMACS_INT gc_relative_threshold;
220 /* Minimum number of bytes of consing since GC before next GC,
221 when memory is full. */
223 EMACS_INT memory_full_cons_threshold;
225 /* True during GC. */
227 bool gc_in_progress;
229 /* True means abort if try to GC.
230 This is for code which is written on the assumption that
231 no GC will happen, so as to verify that assumption. */
233 bool abort_on_gc;
235 /* Number of live and free conses etc. */
237 static EMACS_INT total_conses, total_markers, total_symbols, total_buffers;
238 static EMACS_INT total_free_conses, total_free_markers, total_free_symbols;
239 static EMACS_INT total_free_floats, total_floats;
241 /* Points to memory space allocated as "spare", to be freed if we run
242 out of memory. We keep one large block, four cons-blocks, and
243 two string blocks. */
245 static char *spare_memory[7];
247 /* Amount of spare memory to keep in large reserve block, or to see
248 whether this much is available when malloc fails on a larger request. */
250 #define SPARE_MEMORY (1 << 14)
252 /* Initialize it to a nonzero value to force it into data space
253 (rather than bss space). That way unexec will remap it into text
254 space (pure), on some systems. We have not implemented the
255 remapping on more recent systems because this is less important
256 nowadays than in the days of small memories and timesharing. */
258 EMACS_INT pure[(PURESIZE + sizeof (EMACS_INT) - 1) / sizeof (EMACS_INT)] = {1,};
259 #define PUREBEG (char *) pure
261 /* Pointer to the pure area, and its size. */
263 static char *purebeg;
264 static ptrdiff_t pure_size;
266 /* Number of bytes of pure storage used before pure storage overflowed.
267 If this is non-zero, this implies that an overflow occurred. */
269 static ptrdiff_t pure_bytes_used_before_overflow;
271 /* Index in pure at which next pure Lisp object will be allocated.. */
273 static ptrdiff_t pure_bytes_used_lisp;
275 /* Number of bytes allocated for non-Lisp objects in pure storage. */
277 static ptrdiff_t pure_bytes_used_non_lisp;
279 /* If nonzero, this is a warning delivered by malloc and not yet
280 displayed. */
282 const char *pending_malloc_warning;
284 #if 0 /* Normally, pointer sanity only on request... */
285 #ifdef ENABLE_CHECKING
286 #define SUSPICIOUS_OBJECT_CHECKING 1
287 #endif
288 #endif
290 /* ... but unconditionally use SUSPICIOUS_OBJECT_CHECKING while the GC
291 bug is unresolved. */
292 #define SUSPICIOUS_OBJECT_CHECKING 1
294 #ifdef SUSPICIOUS_OBJECT_CHECKING
295 struct suspicious_free_record
297 void *suspicious_object;
298 void *backtrace[128];
300 static void *suspicious_objects[32];
301 static int suspicious_object_index;
302 struct suspicious_free_record suspicious_free_history[64] EXTERNALLY_VISIBLE;
303 static int suspicious_free_history_index;
304 /* Find the first currently-monitored suspicious pointer in range
305 [begin,end) or NULL if no such pointer exists. */
306 static void *find_suspicious_object_in_range (void *begin, void *end);
307 static void detect_suspicious_free (void *ptr);
308 #else
309 # define find_suspicious_object_in_range(begin, end) NULL
310 # define detect_suspicious_free(ptr) (void)
311 #endif
313 /* Maximum amount of C stack to save when a GC happens. */
315 #ifndef MAX_SAVE_STACK
316 #define MAX_SAVE_STACK 16000
317 #endif
319 /* Buffer in which we save a copy of the C stack at each GC. */
321 #if MAX_SAVE_STACK > 0
322 static char *stack_copy;
323 static ptrdiff_t stack_copy_size;
325 /* Copy to DEST a block of memory from SRC of size SIZE bytes,
326 avoiding any address sanitization. */
328 static void * ATTRIBUTE_NO_SANITIZE_ADDRESS
329 no_sanitize_memcpy (void *dest, void const *src, size_t size)
331 if (! ADDRESS_SANITIZER)
332 return memcpy (dest, src, size);
333 else
335 size_t i;
336 char *d = dest;
337 char const *s = src;
338 for (i = 0; i < size; i++)
339 d[i] = s[i];
340 return dest;
344 #endif /* MAX_SAVE_STACK > 0 */
346 static void mark_terminals (void);
347 static void gc_sweep (void);
348 static Lisp_Object make_pure_vector (ptrdiff_t);
349 static void mark_buffer (struct buffer *);
351 #if !defined REL_ALLOC || defined SYSTEM_MALLOC || defined HYBRID_MALLOC
352 static void refill_memory_reserve (void);
353 #endif
354 static void compact_small_strings (void);
355 static void free_large_strings (void);
356 extern Lisp_Object which_symbols (Lisp_Object, EMACS_INT) EXTERNALLY_VISIBLE;
358 /* When scanning the C stack for live Lisp objects, Emacs keeps track of
359 what memory allocated via lisp_malloc and lisp_align_malloc is intended
360 for what purpose. This enumeration specifies the type of memory. */
362 enum mem_type
364 MEM_TYPE_NON_LISP,
365 MEM_TYPE_BUFFER,
366 MEM_TYPE_CONS,
367 MEM_TYPE_STRING,
368 MEM_TYPE_MISC,
369 MEM_TYPE_SYMBOL,
370 MEM_TYPE_FLOAT,
371 /* Since all non-bool pseudovectors are small enough to be
372 allocated from vector blocks, this memory type denotes
373 large regular vectors and large bool pseudovectors. */
374 MEM_TYPE_VECTORLIKE,
375 /* Special type to denote vector blocks. */
376 MEM_TYPE_VECTOR_BLOCK,
377 /* Special type to denote reserved memory. */
378 MEM_TYPE_SPARE
381 /* A unique object in pure space used to make some Lisp objects
382 on free lists recognizable in O(1). */
384 static Lisp_Object Vdead;
385 #define DEADP(x) EQ (x, Vdead)
387 #ifdef GC_MALLOC_CHECK
389 enum mem_type allocated_mem_type;
391 #endif /* GC_MALLOC_CHECK */
393 /* A node in the red-black tree describing allocated memory containing
394 Lisp data. Each such block is recorded with its start and end
395 address when it is allocated, and removed from the tree when it
396 is freed.
398 A red-black tree is a balanced binary tree with the following
399 properties:
401 1. Every node is either red or black.
402 2. Every leaf is black.
403 3. If a node is red, then both of its children are black.
404 4. Every simple path from a node to a descendant leaf contains
405 the same number of black nodes.
406 5. The root is always black.
408 When nodes are inserted into the tree, or deleted from the tree,
409 the tree is "fixed" so that these properties are always true.
411 A red-black tree with N internal nodes has height at most 2
412 log(N+1). Searches, insertions and deletions are done in O(log N).
413 Please see a text book about data structures for a detailed
414 description of red-black trees. Any book worth its salt should
415 describe them. */
417 struct mem_node
419 /* Children of this node. These pointers are never NULL. When there
420 is no child, the value is MEM_NIL, which points to a dummy node. */
421 struct mem_node *left, *right;
423 /* The parent of this node. In the root node, this is NULL. */
424 struct mem_node *parent;
426 /* Start and end of allocated region. */
427 void *start, *end;
429 /* Node color. */
430 enum {MEM_BLACK, MEM_RED} color;
432 /* Memory type. */
433 enum mem_type type;
436 /* Base address of stack. Set in main. */
438 Lisp_Object *stack_base;
440 /* Root of the tree describing allocated Lisp memory. */
442 static struct mem_node *mem_root;
444 /* Lowest and highest known address in the heap. */
446 static void *min_heap_address, *max_heap_address;
448 /* Sentinel node of the tree. */
450 static struct mem_node mem_z;
451 #define MEM_NIL &mem_z
453 static struct mem_node *mem_insert (void *, void *, enum mem_type);
454 static void mem_insert_fixup (struct mem_node *);
455 static void mem_rotate_left (struct mem_node *);
456 static void mem_rotate_right (struct mem_node *);
457 static void mem_delete (struct mem_node *);
458 static void mem_delete_fixup (struct mem_node *);
459 static struct mem_node *mem_find (void *);
461 #ifndef DEADP
462 # define DEADP(x) 0
463 #endif
465 /* Addresses of staticpro'd variables. Initialize it to a nonzero
466 value; otherwise some compilers put it into BSS. */
468 enum { NSTATICS = 2048 };
469 static Lisp_Object *staticvec[NSTATICS] = {&Vpurify_flag};
471 /* Index of next unused slot in staticvec. */
473 static int staticidx;
475 static void *pure_alloc (size_t, int);
477 /* Return X rounded to the next multiple of Y. Arguments should not
478 have side effects, as they are evaluated more than once. Assume X
479 + Y - 1 does not overflow. Tune for Y being a power of 2. */
481 #define ROUNDUP(x, y) ((y) & ((y) - 1) \
482 ? ((x) + (y) - 1) - ((x) + (y) - 1) % (y) \
483 : ((x) + (y) - 1) & ~ ((y) - 1))
485 /* Return PTR rounded up to the next multiple of ALIGNMENT. */
487 static void *
488 ALIGN (void *ptr, int alignment)
490 return (void *) ROUNDUP ((uintptr_t) ptr, alignment);
493 /* Extract the pointer hidden within A, if A is not a symbol.
494 If A is a symbol, extract the hidden pointer's offset from lispsym,
495 converted to void *. */
497 #define macro_XPNTR_OR_SYMBOL_OFFSET(a) \
498 ((void *) (intptr_t) (USE_LSB_TAG ? XLI (a) - XTYPE (a) : XLI (a) & VALMASK))
500 /* Extract the pointer hidden within A. */
502 #define macro_XPNTR(a) \
503 ((void *) ((intptr_t) XPNTR_OR_SYMBOL_OFFSET (a) \
504 + (SYMBOLP (a) ? (char *) lispsym : NULL)))
506 /* For pointer access, define XPNTR and XPNTR_OR_SYMBOL_OFFSET as
507 functions, as functions are cleaner and can be used in debuggers.
508 Also, define them as macros if being compiled with GCC without
509 optimization, for performance in that case. The macro_* names are
510 private to this section of code. */
512 static ATTRIBUTE_UNUSED void *
513 XPNTR_OR_SYMBOL_OFFSET (Lisp_Object a)
515 return macro_XPNTR_OR_SYMBOL_OFFSET (a);
517 static ATTRIBUTE_UNUSED void *
518 XPNTR (Lisp_Object a)
520 return macro_XPNTR (a);
523 #if DEFINE_KEY_OPS_AS_MACROS
524 # define XPNTR_OR_SYMBOL_OFFSET(a) macro_XPNTR_OR_SYMBOL_OFFSET (a)
525 # define XPNTR(a) macro_XPNTR (a)
526 #endif
528 static void
529 XFLOAT_INIT (Lisp_Object f, double n)
531 XFLOAT (f)->u.data = n;
534 #ifdef DOUG_LEA_MALLOC
535 static bool
536 pointers_fit_in_lispobj_p (void)
538 return (UINTPTR_MAX <= VAL_MAX) || USE_LSB_TAG;
541 static bool
542 mmap_lisp_allowed_p (void)
544 /* If we can't store all memory addresses in our lisp objects, it's
545 risky to let the heap use mmap and give us addresses from all
546 over our address space. We also can't use mmap for lisp objects
547 if we might dump: unexec doesn't preserve the contents of mmapped
548 regions. */
549 return pointers_fit_in_lispobj_p () && !might_dump;
551 #endif
553 /* Head of a circularly-linked list of extant finalizers. */
554 static struct Lisp_Finalizer finalizers;
556 /* Head of a circularly-linked list of finalizers that must be invoked
557 because we deemed them unreachable. This list must be global, and
558 not a local inside garbage_collect_1, in case we GC again while
559 running finalizers. */
560 static struct Lisp_Finalizer doomed_finalizers;
563 /************************************************************************
564 Malloc
565 ************************************************************************/
567 #if defined SIGDANGER || (!defined SYSTEM_MALLOC && !defined HYBRID_MALLOC)
569 /* Function malloc calls this if it finds we are near exhausting storage. */
571 void
572 malloc_warning (const char *str)
574 pending_malloc_warning = str;
577 #endif
579 /* Display an already-pending malloc warning. */
581 void
582 display_malloc_warning (void)
584 call3 (intern ("display-warning"),
585 intern ("alloc"),
586 build_string (pending_malloc_warning),
587 intern ("emergency"));
588 pending_malloc_warning = 0;
591 /* Called if we can't allocate relocatable space for a buffer. */
593 void
594 buffer_memory_full (ptrdiff_t nbytes)
596 /* If buffers use the relocating allocator, no need to free
597 spare_memory, because we may have plenty of malloc space left
598 that we could get, and if we don't, the malloc that fails will
599 itself cause spare_memory to be freed. If buffers don't use the
600 relocating allocator, treat this like any other failing
601 malloc. */
603 #ifndef REL_ALLOC
604 memory_full (nbytes);
605 #else
606 /* This used to call error, but if we've run out of memory, we could
607 get infinite recursion trying to build the string. */
608 xsignal (Qnil, Vmemory_signal_data);
609 #endif
612 /* A common multiple of the positive integers A and B. Ideally this
613 would be the least common multiple, but there's no way to do that
614 as a constant expression in C, so do the best that we can easily do. */
615 #define COMMON_MULTIPLE(a, b) \
616 ((a) % (b) == 0 ? (a) : (b) % (a) == 0 ? (b) : (a) * (b))
618 #ifndef XMALLOC_OVERRUN_CHECK
619 #define XMALLOC_OVERRUN_CHECK_OVERHEAD 0
620 #else
622 /* Check for overrun in malloc'ed buffers by wrapping a header and trailer
623 around each block.
625 The header consists of XMALLOC_OVERRUN_CHECK_SIZE fixed bytes
626 followed by XMALLOC_OVERRUN_SIZE_SIZE bytes containing the original
627 block size in little-endian order. The trailer consists of
628 XMALLOC_OVERRUN_CHECK_SIZE fixed bytes.
630 The header is used to detect whether this block has been allocated
631 through these functions, as some low-level libc functions may
632 bypass the malloc hooks. */
634 #define XMALLOC_OVERRUN_CHECK_SIZE 16
635 #define XMALLOC_OVERRUN_CHECK_OVERHEAD \
636 (2 * XMALLOC_OVERRUN_CHECK_SIZE + XMALLOC_OVERRUN_SIZE_SIZE)
638 /* Define XMALLOC_OVERRUN_SIZE_SIZE so that (1) it's large enough to
639 hold a size_t value and (2) the header size is a multiple of the
640 alignment that Emacs needs for C types and for USE_LSB_TAG. */
641 #define XMALLOC_BASE_ALIGNMENT alignof (max_align_t)
643 #define XMALLOC_HEADER_ALIGNMENT \
644 COMMON_MULTIPLE (GCALIGNMENT, XMALLOC_BASE_ALIGNMENT)
645 #define XMALLOC_OVERRUN_SIZE_SIZE \
646 (((XMALLOC_OVERRUN_CHECK_SIZE + sizeof (size_t) \
647 + XMALLOC_HEADER_ALIGNMENT - 1) \
648 / XMALLOC_HEADER_ALIGNMENT * XMALLOC_HEADER_ALIGNMENT) \
649 - XMALLOC_OVERRUN_CHECK_SIZE)
651 static char const xmalloc_overrun_check_header[XMALLOC_OVERRUN_CHECK_SIZE] =
652 { '\x9a', '\x9b', '\xae', '\xaf',
653 '\xbf', '\xbe', '\xce', '\xcf',
654 '\xea', '\xeb', '\xec', '\xed',
655 '\xdf', '\xde', '\x9c', '\x9d' };
657 static char const xmalloc_overrun_check_trailer[XMALLOC_OVERRUN_CHECK_SIZE] =
658 { '\xaa', '\xab', '\xac', '\xad',
659 '\xba', '\xbb', '\xbc', '\xbd',
660 '\xca', '\xcb', '\xcc', '\xcd',
661 '\xda', '\xdb', '\xdc', '\xdd' };
663 /* Insert and extract the block size in the header. */
665 static void
666 xmalloc_put_size (unsigned char *ptr, size_t size)
668 int i;
669 for (i = 0; i < XMALLOC_OVERRUN_SIZE_SIZE; i++)
671 *--ptr = size & ((1 << CHAR_BIT) - 1);
672 size >>= CHAR_BIT;
676 static size_t
677 xmalloc_get_size (unsigned char *ptr)
679 size_t size = 0;
680 int i;
681 ptr -= XMALLOC_OVERRUN_SIZE_SIZE;
682 for (i = 0; i < XMALLOC_OVERRUN_SIZE_SIZE; i++)
684 size <<= CHAR_BIT;
685 size += *ptr++;
687 return size;
691 /* Like malloc, but wraps allocated block with header and trailer. */
693 static void *
694 overrun_check_malloc (size_t size)
696 register unsigned char *val;
697 if (SIZE_MAX - XMALLOC_OVERRUN_CHECK_OVERHEAD < size)
698 emacs_abort ();
700 val = malloc (size + XMALLOC_OVERRUN_CHECK_OVERHEAD);
701 if (val)
703 memcpy (val, xmalloc_overrun_check_header, XMALLOC_OVERRUN_CHECK_SIZE);
704 val += XMALLOC_OVERRUN_CHECK_SIZE + XMALLOC_OVERRUN_SIZE_SIZE;
705 xmalloc_put_size (val, size);
706 memcpy (val + size, xmalloc_overrun_check_trailer,
707 XMALLOC_OVERRUN_CHECK_SIZE);
709 return val;
713 /* Like realloc, but checks old block for overrun, and wraps new block
714 with header and trailer. */
716 static void *
717 overrun_check_realloc (void *block, size_t size)
719 register unsigned char *val = (unsigned char *) block;
720 if (SIZE_MAX - XMALLOC_OVERRUN_CHECK_OVERHEAD < size)
721 emacs_abort ();
723 if (val
724 && memcmp (xmalloc_overrun_check_header,
725 val - XMALLOC_OVERRUN_CHECK_SIZE - XMALLOC_OVERRUN_SIZE_SIZE,
726 XMALLOC_OVERRUN_CHECK_SIZE) == 0)
728 size_t osize = xmalloc_get_size (val);
729 if (memcmp (xmalloc_overrun_check_trailer, val + osize,
730 XMALLOC_OVERRUN_CHECK_SIZE))
731 emacs_abort ();
732 memset (val + osize, 0, XMALLOC_OVERRUN_CHECK_SIZE);
733 val -= XMALLOC_OVERRUN_CHECK_SIZE + XMALLOC_OVERRUN_SIZE_SIZE;
734 memset (val, 0, XMALLOC_OVERRUN_CHECK_SIZE + XMALLOC_OVERRUN_SIZE_SIZE);
737 val = realloc (val, size + XMALLOC_OVERRUN_CHECK_OVERHEAD);
739 if (val)
741 memcpy (val, xmalloc_overrun_check_header, XMALLOC_OVERRUN_CHECK_SIZE);
742 val += XMALLOC_OVERRUN_CHECK_SIZE + XMALLOC_OVERRUN_SIZE_SIZE;
743 xmalloc_put_size (val, size);
744 memcpy (val + size, xmalloc_overrun_check_trailer,
745 XMALLOC_OVERRUN_CHECK_SIZE);
747 return val;
750 /* Like free, but checks block for overrun. */
752 static void
753 overrun_check_free (void *block)
755 unsigned char *val = (unsigned char *) block;
757 if (val
758 && memcmp (xmalloc_overrun_check_header,
759 val - XMALLOC_OVERRUN_CHECK_SIZE - XMALLOC_OVERRUN_SIZE_SIZE,
760 XMALLOC_OVERRUN_CHECK_SIZE) == 0)
762 size_t osize = xmalloc_get_size (val);
763 if (memcmp (xmalloc_overrun_check_trailer, val + osize,
764 XMALLOC_OVERRUN_CHECK_SIZE))
765 emacs_abort ();
766 #ifdef XMALLOC_CLEAR_FREE_MEMORY
767 val -= XMALLOC_OVERRUN_CHECK_SIZE + XMALLOC_OVERRUN_SIZE_SIZE;
768 memset (val, 0xff, osize + XMALLOC_OVERRUN_CHECK_OVERHEAD);
769 #else
770 memset (val + osize, 0, XMALLOC_OVERRUN_CHECK_SIZE);
771 val -= XMALLOC_OVERRUN_CHECK_SIZE + XMALLOC_OVERRUN_SIZE_SIZE;
772 memset (val, 0, XMALLOC_OVERRUN_CHECK_SIZE + XMALLOC_OVERRUN_SIZE_SIZE);
773 #endif
776 free (val);
779 #undef malloc
780 #undef realloc
781 #undef free
782 #define malloc overrun_check_malloc
783 #define realloc overrun_check_realloc
784 #define free overrun_check_free
785 #endif
787 /* If compiled with XMALLOC_BLOCK_INPUT_CHECK, define a symbol
788 BLOCK_INPUT_IN_MEMORY_ALLOCATORS that is visible to the debugger.
789 If that variable is set, block input while in one of Emacs's memory
790 allocation functions. There should be no need for this debugging
791 option, since signal handlers do not allocate memory, but Emacs
792 formerly allocated memory in signal handlers and this compile-time
793 option remains as a way to help debug the issue should it rear its
794 ugly head again. */
795 #ifdef XMALLOC_BLOCK_INPUT_CHECK
796 bool block_input_in_memory_allocators EXTERNALLY_VISIBLE;
797 static void
798 malloc_block_input (void)
800 if (block_input_in_memory_allocators)
801 block_input ();
803 static void
804 malloc_unblock_input (void)
806 if (block_input_in_memory_allocators)
807 unblock_input ();
809 # define MALLOC_BLOCK_INPUT malloc_block_input ()
810 # define MALLOC_UNBLOCK_INPUT malloc_unblock_input ()
811 #else
812 # define MALLOC_BLOCK_INPUT ((void) 0)
813 # define MALLOC_UNBLOCK_INPUT ((void) 0)
814 #endif
816 #define MALLOC_PROBE(size) \
817 do { \
818 if (profiler_memory_running) \
819 malloc_probe (size); \
820 } while (0)
822 static void *lmalloc (size_t) ATTRIBUTE_MALLOC_SIZE ((1));
823 static void *lrealloc (void *, size_t);
825 /* Like malloc but check for no memory and block interrupt input. */
827 void *
828 xmalloc (size_t size)
830 void *val;
832 MALLOC_BLOCK_INPUT;
833 val = lmalloc (size);
834 MALLOC_UNBLOCK_INPUT;
836 if (!val && size)
837 memory_full (size);
838 MALLOC_PROBE (size);
839 return val;
842 /* Like the above, but zeroes out the memory just allocated. */
844 void *
845 xzalloc (size_t size)
847 void *val;
849 MALLOC_BLOCK_INPUT;
850 val = lmalloc (size);
851 MALLOC_UNBLOCK_INPUT;
853 if (!val && size)
854 memory_full (size);
855 memset (val, 0, size);
856 MALLOC_PROBE (size);
857 return val;
860 /* Like realloc but check for no memory and block interrupt input.. */
862 void *
863 xrealloc (void *block, size_t size)
865 void *val;
867 MALLOC_BLOCK_INPUT;
868 /* We must call malloc explicitly when BLOCK is 0, since some
869 reallocs don't do this. */
870 if (! block)
871 val = lmalloc (size);
872 else
873 val = lrealloc (block, size);
874 MALLOC_UNBLOCK_INPUT;
876 if (!val && size)
877 memory_full (size);
878 MALLOC_PROBE (size);
879 return val;
883 /* Like free but block interrupt input. */
885 void
886 xfree (void *block)
888 if (!block)
889 return;
890 MALLOC_BLOCK_INPUT;
891 free (block);
892 MALLOC_UNBLOCK_INPUT;
893 /* We don't call refill_memory_reserve here
894 because in practice the call in r_alloc_free seems to suffice. */
898 /* Other parts of Emacs pass large int values to allocator functions
899 expecting ptrdiff_t. This is portable in practice, but check it to
900 be safe. */
901 verify (INT_MAX <= PTRDIFF_MAX);
904 /* Allocate an array of NITEMS items, each of size ITEM_SIZE.
905 Signal an error on memory exhaustion, and block interrupt input. */
907 void *
908 xnmalloc (ptrdiff_t nitems, ptrdiff_t item_size)
910 eassert (0 <= nitems && 0 < item_size);
911 ptrdiff_t nbytes;
912 if (INT_MULTIPLY_WRAPV (nitems, item_size, &nbytes) || SIZE_MAX < nbytes)
913 memory_full (SIZE_MAX);
914 return xmalloc (nbytes);
918 /* Reallocate an array PA to make it of NITEMS items, each of size ITEM_SIZE.
919 Signal an error on memory exhaustion, and block interrupt input. */
921 void *
922 xnrealloc (void *pa, ptrdiff_t nitems, ptrdiff_t item_size)
924 eassert (0 <= nitems && 0 < item_size);
925 ptrdiff_t nbytes;
926 if (INT_MULTIPLY_WRAPV (nitems, item_size, &nbytes) || SIZE_MAX < nbytes)
927 memory_full (SIZE_MAX);
928 return xrealloc (pa, nbytes);
932 /* Grow PA, which points to an array of *NITEMS items, and return the
933 location of the reallocated array, updating *NITEMS to reflect its
934 new size. The new array will contain at least NITEMS_INCR_MIN more
935 items, but will not contain more than NITEMS_MAX items total.
936 ITEM_SIZE is the size of each item, in bytes.
938 ITEM_SIZE and NITEMS_INCR_MIN must be positive. *NITEMS must be
939 nonnegative. If NITEMS_MAX is -1, it is treated as if it were
940 infinity.
942 If PA is null, then allocate a new array instead of reallocating
943 the old one.
945 Block interrupt input as needed. If memory exhaustion occurs, set
946 *NITEMS to zero if PA is null, and signal an error (i.e., do not
947 return).
949 Thus, to grow an array A without saving its old contents, do
950 { xfree (A); A = NULL; A = xpalloc (NULL, &AITEMS, ...); }.
951 The A = NULL avoids a dangling pointer if xpalloc exhausts memory
952 and signals an error, and later this code is reexecuted and
953 attempts to free A. */
955 void *
956 xpalloc (void *pa, ptrdiff_t *nitems, ptrdiff_t nitems_incr_min,
957 ptrdiff_t nitems_max, ptrdiff_t item_size)
959 ptrdiff_t n0 = *nitems;
960 eassume (0 < item_size && 0 < nitems_incr_min && 0 <= n0 && -1 <= nitems_max);
962 /* The approximate size to use for initial small allocation
963 requests. This is the largest "small" request for the GNU C
964 library malloc. */
965 enum { DEFAULT_MXFAST = 64 * sizeof (size_t) / 4 };
967 /* If the array is tiny, grow it to about (but no greater than)
968 DEFAULT_MXFAST bytes. Otherwise, grow it by about 50%.
969 Adjust the growth according to three constraints: NITEMS_INCR_MIN,
970 NITEMS_MAX, and what the C language can represent safely. */
972 ptrdiff_t n, nbytes;
973 if (INT_ADD_WRAPV (n0, n0 >> 1, &n))
974 n = PTRDIFF_MAX;
975 if (0 <= nitems_max && nitems_max < n)
976 n = nitems_max;
978 ptrdiff_t adjusted_nbytes
979 = ((INT_MULTIPLY_WRAPV (n, item_size, &nbytes) || SIZE_MAX < nbytes)
980 ? min (PTRDIFF_MAX, SIZE_MAX)
981 : nbytes < DEFAULT_MXFAST ? DEFAULT_MXFAST : 0);
982 if (adjusted_nbytes)
984 n = adjusted_nbytes / item_size;
985 nbytes = adjusted_nbytes - adjusted_nbytes % item_size;
988 if (! pa)
989 *nitems = 0;
990 if (n - n0 < nitems_incr_min
991 && (INT_ADD_WRAPV (n0, nitems_incr_min, &n)
992 || (0 <= nitems_max && nitems_max < n)
993 || INT_MULTIPLY_WRAPV (n, item_size, &nbytes)))
994 memory_full (SIZE_MAX);
995 pa = xrealloc (pa, nbytes);
996 *nitems = n;
997 return pa;
1001 /* Like strdup, but uses xmalloc. */
1003 char *
1004 xstrdup (const char *s)
1006 ptrdiff_t size;
1007 eassert (s);
1008 size = strlen (s) + 1;
1009 return memcpy (xmalloc (size), s, size);
1012 /* Like above, but duplicates Lisp string to C string. */
1014 char *
1015 xlispstrdup (Lisp_Object string)
1017 ptrdiff_t size = SBYTES (string) + 1;
1018 return memcpy (xmalloc (size), SSDATA (string), size);
1021 /* Assign to *PTR a copy of STRING, freeing any storage *PTR formerly
1022 pointed to. If STRING is null, assign it without copying anything.
1023 Allocate before freeing, to avoid a dangling pointer if allocation
1024 fails. */
1026 void
1027 dupstring (char **ptr, char const *string)
1029 char *old = *ptr;
1030 *ptr = string ? xstrdup (string) : 0;
1031 xfree (old);
1035 /* Like putenv, but (1) use the equivalent of xmalloc and (2) the
1036 argument is a const pointer. */
1038 void
1039 xputenv (char const *string)
1041 if (putenv ((char *) string) != 0)
1042 memory_full (0);
1045 /* Return a newly allocated memory block of SIZE bytes, remembering
1046 to free it when unwinding. */
1047 void *
1048 record_xmalloc (size_t size)
1050 void *p = xmalloc (size);
1051 record_unwind_protect_ptr (xfree, p);
1052 return p;
1056 /* Like malloc but used for allocating Lisp data. NBYTES is the
1057 number of bytes to allocate, TYPE describes the intended use of the
1058 allocated memory block (for strings, for conses, ...). */
1060 #if ! USE_LSB_TAG
1061 void *lisp_malloc_loser EXTERNALLY_VISIBLE;
1062 #endif
1064 static void *
1065 lisp_malloc (size_t nbytes, enum mem_type type)
1067 register void *val;
1069 MALLOC_BLOCK_INPUT;
1071 #ifdef GC_MALLOC_CHECK
1072 allocated_mem_type = type;
1073 #endif
1075 val = lmalloc (nbytes);
1077 #if ! USE_LSB_TAG
1078 /* If the memory just allocated cannot be addressed thru a Lisp
1079 object's pointer, and it needs to be,
1080 that's equivalent to running out of memory. */
1081 if (val && type != MEM_TYPE_NON_LISP)
1083 Lisp_Object tem;
1084 XSETCONS (tem, (char *) val + nbytes - 1);
1085 if ((char *) XCONS (tem) != (char *) val + nbytes - 1)
1087 lisp_malloc_loser = val;
1088 free (val);
1089 val = 0;
1092 #endif
1094 #ifndef GC_MALLOC_CHECK
1095 if (val && type != MEM_TYPE_NON_LISP)
1096 mem_insert (val, (char *) val + nbytes, type);
1097 #endif
1099 MALLOC_UNBLOCK_INPUT;
1100 if (!val && nbytes)
1101 memory_full (nbytes);
1102 MALLOC_PROBE (nbytes);
1103 return val;
1106 /* Free BLOCK. This must be called to free memory allocated with a
1107 call to lisp_malloc. */
1109 static void
1110 lisp_free (void *block)
1112 MALLOC_BLOCK_INPUT;
1113 free (block);
1114 #ifndef GC_MALLOC_CHECK
1115 mem_delete (mem_find (block));
1116 #endif
1117 MALLOC_UNBLOCK_INPUT;
1120 /***** Allocation of aligned blocks of memory to store Lisp data. *****/
1122 /* The entry point is lisp_align_malloc which returns blocks of at most
1123 BLOCK_BYTES and guarantees they are aligned on a BLOCK_ALIGN boundary. */
1125 /* Use aligned_alloc if it or a simple substitute is available.
1126 Address sanitization breaks aligned allocation, as of gcc 4.8.2 and
1127 clang 3.3 anyway. Aligned allocation is incompatible with
1128 unexmacosx.c, so don't use it on Darwin. */
1130 #if ! ADDRESS_SANITIZER && !defined DARWIN_OS
1131 # if (defined HAVE_ALIGNED_ALLOC \
1132 || (defined HYBRID_MALLOC \
1133 ? defined HAVE_POSIX_MEMALIGN \
1134 : !defined SYSTEM_MALLOC && !defined DOUG_LEA_MALLOC))
1135 # define USE_ALIGNED_ALLOC 1
1136 # elif !defined HYBRID_MALLOC && defined HAVE_POSIX_MEMALIGN
1137 # define USE_ALIGNED_ALLOC 1
1138 # define aligned_alloc my_aligned_alloc /* Avoid collision with lisp.h. */
1139 static void *
1140 aligned_alloc (size_t alignment, size_t size)
1142 void *p;
1143 return posix_memalign (&p, alignment, size) == 0 ? p : 0;
1145 # endif
1146 #endif
1148 /* BLOCK_ALIGN has to be a power of 2. */
1149 #define BLOCK_ALIGN (1 << 10)
1151 /* Padding to leave at the end of a malloc'd block. This is to give
1152 malloc a chance to minimize the amount of memory wasted to alignment.
1153 It should be tuned to the particular malloc library used.
1154 On glibc-2.3.2, malloc never tries to align, so a padding of 0 is best.
1155 aligned_alloc on the other hand would ideally prefer a value of 4
1156 because otherwise, there's 1020 bytes wasted between each ablocks.
1157 In Emacs, testing shows that those 1020 can most of the time be
1158 efficiently used by malloc to place other objects, so a value of 0 can
1159 still preferable unless you have a lot of aligned blocks and virtually
1160 nothing else. */
1161 #define BLOCK_PADDING 0
1162 #define BLOCK_BYTES \
1163 (BLOCK_ALIGN - sizeof (struct ablocks *) - BLOCK_PADDING)
1165 /* Internal data structures and constants. */
1167 #define ABLOCKS_SIZE 16
1169 /* An aligned block of memory. */
1170 struct ablock
1172 union
1174 char payload[BLOCK_BYTES];
1175 struct ablock *next_free;
1176 } x;
1177 /* `abase' is the aligned base of the ablocks. */
1178 /* It is overloaded to hold the virtual `busy' field that counts
1179 the number of used ablock in the parent ablocks.
1180 The first ablock has the `busy' field, the others have the `abase'
1181 field. To tell the difference, we assume that pointers will have
1182 integer values larger than 2 * ABLOCKS_SIZE. The lowest bit of `busy'
1183 is used to tell whether the real base of the parent ablocks is `abase'
1184 (if not, the word before the first ablock holds a pointer to the
1185 real base). */
1186 struct ablocks *abase;
1187 /* The padding of all but the last ablock is unused. The padding of
1188 the last ablock in an ablocks is not allocated. */
1189 #if BLOCK_PADDING
1190 char padding[BLOCK_PADDING];
1191 #endif
1194 /* A bunch of consecutive aligned blocks. */
1195 struct ablocks
1197 struct ablock blocks[ABLOCKS_SIZE];
1200 /* Size of the block requested from malloc or aligned_alloc. */
1201 #define ABLOCKS_BYTES (sizeof (struct ablocks) - BLOCK_PADDING)
1203 #define ABLOCK_ABASE(block) \
1204 (((uintptr_t) (block)->abase) <= (1 + 2 * ABLOCKS_SIZE) \
1205 ? (struct ablocks *)(block) \
1206 : (block)->abase)
1208 /* Virtual `busy' field. */
1209 #define ABLOCKS_BUSY(abase) ((abase)->blocks[0].abase)
1211 /* Pointer to the (not necessarily aligned) malloc block. */
1212 #ifdef USE_ALIGNED_ALLOC
1213 #define ABLOCKS_BASE(abase) (abase)
1214 #else
1215 #define ABLOCKS_BASE(abase) \
1216 (1 & (intptr_t) ABLOCKS_BUSY (abase) ? abase : ((void **)abase)[-1])
1217 #endif
1219 /* The list of free ablock. */
1220 static struct ablock *free_ablock;
1222 /* Allocate an aligned block of nbytes.
1223 Alignment is on a multiple of BLOCK_ALIGN and `nbytes' has to be
1224 smaller or equal to BLOCK_BYTES. */
1225 static void *
1226 lisp_align_malloc (size_t nbytes, enum mem_type type)
1228 void *base, *val;
1229 struct ablocks *abase;
1231 eassert (nbytes <= BLOCK_BYTES);
1233 MALLOC_BLOCK_INPUT;
1235 #ifdef GC_MALLOC_CHECK
1236 allocated_mem_type = type;
1237 #endif
1239 if (!free_ablock)
1241 int i;
1242 intptr_t aligned; /* int gets warning casting to 64-bit pointer. */
1244 #ifdef DOUG_LEA_MALLOC
1245 if (!mmap_lisp_allowed_p ())
1246 mallopt (M_MMAP_MAX, 0);
1247 #endif
1249 #ifdef USE_ALIGNED_ALLOC
1250 abase = base = aligned_alloc (BLOCK_ALIGN, ABLOCKS_BYTES);
1251 #else
1252 base = malloc (ABLOCKS_BYTES);
1253 abase = ALIGN (base, BLOCK_ALIGN);
1254 #endif
1256 if (base == 0)
1258 MALLOC_UNBLOCK_INPUT;
1259 memory_full (ABLOCKS_BYTES);
1262 aligned = (base == abase);
1263 if (!aligned)
1264 ((void **) abase)[-1] = base;
1266 #ifdef DOUG_LEA_MALLOC
1267 if (!mmap_lisp_allowed_p ())
1268 mallopt (M_MMAP_MAX, MMAP_MAX_AREAS);
1269 #endif
1271 #if ! USE_LSB_TAG
1272 /* If the memory just allocated cannot be addressed thru a Lisp
1273 object's pointer, and it needs to be, that's equivalent to
1274 running out of memory. */
1275 if (type != MEM_TYPE_NON_LISP)
1277 Lisp_Object tem;
1278 char *end = (char *) base + ABLOCKS_BYTES - 1;
1279 XSETCONS (tem, end);
1280 if ((char *) XCONS (tem) != end)
1282 lisp_malloc_loser = base;
1283 free (base);
1284 MALLOC_UNBLOCK_INPUT;
1285 memory_full (SIZE_MAX);
1288 #endif
1290 /* Initialize the blocks and put them on the free list.
1291 If `base' was not properly aligned, we can't use the last block. */
1292 for (i = 0; i < (aligned ? ABLOCKS_SIZE : ABLOCKS_SIZE - 1); i++)
1294 abase->blocks[i].abase = abase;
1295 abase->blocks[i].x.next_free = free_ablock;
1296 free_ablock = &abase->blocks[i];
1298 ABLOCKS_BUSY (abase) = (struct ablocks *) aligned;
1300 eassert (0 == ((uintptr_t) abase) % BLOCK_ALIGN);
1301 eassert (ABLOCK_ABASE (&abase->blocks[3]) == abase); /* 3 is arbitrary */
1302 eassert (ABLOCK_ABASE (&abase->blocks[0]) == abase);
1303 eassert (ABLOCKS_BASE (abase) == base);
1304 eassert (aligned == (intptr_t) ABLOCKS_BUSY (abase));
1307 abase = ABLOCK_ABASE (free_ablock);
1308 ABLOCKS_BUSY (abase)
1309 = (struct ablocks *) (2 + (intptr_t) ABLOCKS_BUSY (abase));
1310 val = free_ablock;
1311 free_ablock = free_ablock->x.next_free;
1313 #ifndef GC_MALLOC_CHECK
1314 if (type != MEM_TYPE_NON_LISP)
1315 mem_insert (val, (char *) val + nbytes, type);
1316 #endif
1318 MALLOC_UNBLOCK_INPUT;
1320 MALLOC_PROBE (nbytes);
1322 eassert (0 == ((uintptr_t) val) % BLOCK_ALIGN);
1323 return val;
1326 static void
1327 lisp_align_free (void *block)
1329 struct ablock *ablock = block;
1330 struct ablocks *abase = ABLOCK_ABASE (ablock);
1332 MALLOC_BLOCK_INPUT;
1333 #ifndef GC_MALLOC_CHECK
1334 mem_delete (mem_find (block));
1335 #endif
1336 /* Put on free list. */
1337 ablock->x.next_free = free_ablock;
1338 free_ablock = ablock;
1339 /* Update busy count. */
1340 ABLOCKS_BUSY (abase)
1341 = (struct ablocks *) (-2 + (intptr_t) ABLOCKS_BUSY (abase));
1343 if (2 > (intptr_t) ABLOCKS_BUSY (abase))
1344 { /* All the blocks are free. */
1345 int i = 0, aligned = (intptr_t) ABLOCKS_BUSY (abase);
1346 struct ablock **tem = &free_ablock;
1347 struct ablock *atop = &abase->blocks[aligned ? ABLOCKS_SIZE : ABLOCKS_SIZE - 1];
1349 while (*tem)
1351 if (*tem >= (struct ablock *) abase && *tem < atop)
1353 i++;
1354 *tem = (*tem)->x.next_free;
1356 else
1357 tem = &(*tem)->x.next_free;
1359 eassert ((aligned & 1) == aligned);
1360 eassert (i == (aligned ? ABLOCKS_SIZE : ABLOCKS_SIZE - 1));
1361 #ifdef USE_POSIX_MEMALIGN
1362 eassert ((uintptr_t) ABLOCKS_BASE (abase) % BLOCK_ALIGN == 0);
1363 #endif
1364 free (ABLOCKS_BASE (abase));
1366 MALLOC_UNBLOCK_INPUT;
1369 #if !defined __GNUC__ && !defined __alignof__
1370 # define __alignof__(type) alignof (type)
1371 #endif
1373 /* True if malloc returns a multiple of GCALIGNMENT. In practice this
1374 holds if __alignof__ (max_align_t) is a multiple. Use __alignof__
1375 if available, as otherwise this check would fail with GCC x86.
1376 This is a macro, not an enum constant, for portability to HP-UX
1377 10.20 cc and AIX 3.2.5 xlc. */
1378 #define MALLOC_IS_GC_ALIGNED (__alignof__ (max_align_t) % GCALIGNMENT == 0)
1380 /* True if P is suitably aligned for SIZE, where Lisp alignment may be
1381 needed if SIZE is Lisp-aligned. */
1383 static bool
1384 laligned (void *p, size_t size)
1386 return (MALLOC_IS_GC_ALIGNED || (intptr_t) p % GCALIGNMENT == 0
1387 || size % GCALIGNMENT != 0);
1390 /* Like malloc and realloc except that if SIZE is Lisp-aligned, make
1391 sure the result is too, if necessary by reallocating (typically
1392 with larger and larger sizes) until the allocator returns a
1393 Lisp-aligned pointer. Code that needs to allocate C heap memory
1394 for a Lisp object should use one of these functions to obtain a
1395 pointer P; that way, if T is an enum Lisp_Type value and L ==
1396 make_lisp_ptr (P, T), then XPNTR (L) == P and XTYPE (L) == T.
1398 On typical modern platforms these functions' loops do not iterate.
1399 On now-rare (and perhaps nonexistent) platforms, the loops in
1400 theory could repeat forever. If an infinite loop is possible on a
1401 platform, a build would surely loop and the builder can then send
1402 us a bug report. Adding a counter to try to detect any such loop
1403 would complicate the code (and possibly introduce bugs, in code
1404 that's never really exercised) for little benefit. */
1406 static void *
1407 lmalloc (size_t size)
1409 #if USE_ALIGNED_ALLOC
1410 if (! MALLOC_IS_GC_ALIGNED)
1411 return aligned_alloc (GCALIGNMENT, size);
1412 #endif
1414 void *p;
1415 while (true)
1417 p = malloc (size);
1418 if (laligned (p, size))
1419 break;
1420 free (p);
1421 size_t bigger;
1422 if (! INT_ADD_WRAPV (size, GCALIGNMENT, &bigger))
1423 size = bigger;
1426 eassert ((intptr_t) p % GCALIGNMENT == 0);
1427 return p;
1430 static void *
1431 lrealloc (void *p, size_t size)
1433 while (true)
1435 p = realloc (p, size);
1436 if (laligned (p, size))
1437 break;
1438 size_t bigger;
1439 if (! INT_ADD_WRAPV (size, GCALIGNMENT, &bigger))
1440 size = bigger;
1443 eassert ((intptr_t) p % GCALIGNMENT == 0);
1444 return p;
1448 /***********************************************************************
1449 Interval Allocation
1450 ***********************************************************************/
1452 /* Number of intervals allocated in an interval_block structure.
1453 The 1020 is 1024 minus malloc overhead. */
1455 #define INTERVAL_BLOCK_SIZE \
1456 ((1020 - sizeof (struct interval_block *)) / sizeof (struct interval))
1458 /* Intervals are allocated in chunks in the form of an interval_block
1459 structure. */
1461 struct interval_block
1463 /* Place `intervals' first, to preserve alignment. */
1464 struct interval intervals[INTERVAL_BLOCK_SIZE];
1465 struct interval_block *next;
1468 /* Current interval block. Its `next' pointer points to older
1469 blocks. */
1471 static struct interval_block *interval_block;
1473 /* Index in interval_block above of the next unused interval
1474 structure. */
1476 static int interval_block_index = INTERVAL_BLOCK_SIZE;
1478 /* Number of free and live intervals. */
1480 static EMACS_INT total_free_intervals, total_intervals;
1482 /* List of free intervals. */
1484 static INTERVAL interval_free_list;
1486 /* Return a new interval. */
1488 INTERVAL
1489 make_interval (void)
1491 INTERVAL val;
1493 MALLOC_BLOCK_INPUT;
1495 if (interval_free_list)
1497 val = interval_free_list;
1498 interval_free_list = INTERVAL_PARENT (interval_free_list);
1500 else
1502 if (interval_block_index == INTERVAL_BLOCK_SIZE)
1504 struct interval_block *newi
1505 = lisp_malloc (sizeof *newi, MEM_TYPE_NON_LISP);
1507 newi->next = interval_block;
1508 interval_block = newi;
1509 interval_block_index = 0;
1510 total_free_intervals += INTERVAL_BLOCK_SIZE;
1512 val = &interval_block->intervals[interval_block_index++];
1515 MALLOC_UNBLOCK_INPUT;
1517 consing_since_gc += sizeof (struct interval);
1518 intervals_consed++;
1519 total_free_intervals--;
1520 RESET_INTERVAL (val);
1521 val->gcmarkbit = 0;
1522 return val;
1526 /* Mark Lisp objects in interval I. */
1528 static void
1529 mark_interval (register INTERVAL i, Lisp_Object dummy)
1531 /* Intervals should never be shared. So, if extra internal checking is
1532 enabled, GC aborts if it seems to have visited an interval twice. */
1533 eassert (!i->gcmarkbit);
1534 i->gcmarkbit = 1;
1535 mark_object (i->plist);
1538 /* Mark the interval tree rooted in I. */
1540 #define MARK_INTERVAL_TREE(i) \
1541 do { \
1542 if (i && !i->gcmarkbit) \
1543 traverse_intervals_noorder (i, mark_interval, Qnil); \
1544 } while (0)
1546 /***********************************************************************
1547 String Allocation
1548 ***********************************************************************/
1550 /* Lisp_Strings are allocated in string_block structures. When a new
1551 string_block is allocated, all the Lisp_Strings it contains are
1552 added to a free-list string_free_list. When a new Lisp_String is
1553 needed, it is taken from that list. During the sweep phase of GC,
1554 string_blocks that are entirely free are freed, except two which
1555 we keep.
1557 String data is allocated from sblock structures. Strings larger
1558 than LARGE_STRING_BYTES, get their own sblock, data for smaller
1559 strings is sub-allocated out of sblocks of size SBLOCK_SIZE.
1561 Sblocks consist internally of sdata structures, one for each
1562 Lisp_String. The sdata structure points to the Lisp_String it
1563 belongs to. The Lisp_String points back to the `u.data' member of
1564 its sdata structure.
1566 When a Lisp_String is freed during GC, it is put back on
1567 string_free_list, and its `data' member and its sdata's `string'
1568 pointer is set to null. The size of the string is recorded in the
1569 `n.nbytes' member of the sdata. So, sdata structures that are no
1570 longer used, can be easily recognized, and it's easy to compact the
1571 sblocks of small strings which we do in compact_small_strings. */
1573 /* Size in bytes of an sblock structure used for small strings. This
1574 is 8192 minus malloc overhead. */
1576 #define SBLOCK_SIZE 8188
1578 /* Strings larger than this are considered large strings. String data
1579 for large strings is allocated from individual sblocks. */
1581 #define LARGE_STRING_BYTES 1024
1583 /* The SDATA typedef is a struct or union describing string memory
1584 sub-allocated from an sblock. This is where the contents of Lisp
1585 strings are stored. */
1587 struct sdata
1589 /* Back-pointer to the string this sdata belongs to. If null, this
1590 structure is free, and NBYTES (in this structure or in the union below)
1591 contains the string's byte size (the same value that STRING_BYTES
1592 would return if STRING were non-null). If non-null, STRING_BYTES
1593 (STRING) is the size of the data, and DATA contains the string's
1594 contents. */
1595 struct Lisp_String *string;
1597 #ifdef GC_CHECK_STRING_BYTES
1598 ptrdiff_t nbytes;
1599 #endif
1601 unsigned char data[FLEXIBLE_ARRAY_MEMBER];
1604 #ifdef GC_CHECK_STRING_BYTES
1606 typedef struct sdata sdata;
1607 #define SDATA_NBYTES(S) (S)->nbytes
1608 #define SDATA_DATA(S) (S)->data
1610 #else
1612 typedef union
1614 struct Lisp_String *string;
1616 /* When STRING is nonnull, this union is actually of type 'struct sdata',
1617 which has a flexible array member. However, if implemented by
1618 giving this union a member of type 'struct sdata', the union
1619 could not be the last (flexible) member of 'struct sblock',
1620 because C99 prohibits a flexible array member from having a type
1621 that is itself a flexible array. So, comment this member out here,
1622 but remember that the option's there when using this union. */
1623 #if 0
1624 struct sdata u;
1625 #endif
1627 /* When STRING is null. */
1628 struct
1630 struct Lisp_String *string;
1631 ptrdiff_t nbytes;
1632 } n;
1633 } sdata;
1635 #define SDATA_NBYTES(S) (S)->n.nbytes
1636 #define SDATA_DATA(S) ((struct sdata *) (S))->data
1638 #endif /* not GC_CHECK_STRING_BYTES */
1640 enum { SDATA_DATA_OFFSET = offsetof (struct sdata, data) };
1642 /* Structure describing a block of memory which is sub-allocated to
1643 obtain string data memory for strings. Blocks for small strings
1644 are of fixed size SBLOCK_SIZE. Blocks for large strings are made
1645 as large as needed. */
1647 struct sblock
1649 /* Next in list. */
1650 struct sblock *next;
1652 /* Pointer to the next free sdata block. This points past the end
1653 of the sblock if there isn't any space left in this block. */
1654 sdata *next_free;
1656 /* String data. */
1657 sdata data[FLEXIBLE_ARRAY_MEMBER];
1660 /* Number of Lisp strings in a string_block structure. The 1020 is
1661 1024 minus malloc overhead. */
1663 #define STRING_BLOCK_SIZE \
1664 ((1020 - sizeof (struct string_block *)) / sizeof (struct Lisp_String))
1666 /* Structure describing a block from which Lisp_String structures
1667 are allocated. */
1669 struct string_block
1671 /* Place `strings' first, to preserve alignment. */
1672 struct Lisp_String strings[STRING_BLOCK_SIZE];
1673 struct string_block *next;
1676 /* Head and tail of the list of sblock structures holding Lisp string
1677 data. We always allocate from current_sblock. The NEXT pointers
1678 in the sblock structures go from oldest_sblock to current_sblock. */
1680 static struct sblock *oldest_sblock, *current_sblock;
1682 /* List of sblocks for large strings. */
1684 static struct sblock *large_sblocks;
1686 /* List of string_block structures. */
1688 static struct string_block *string_blocks;
1690 /* Free-list of Lisp_Strings. */
1692 static struct Lisp_String *string_free_list;
1694 /* Number of live and free Lisp_Strings. */
1696 static EMACS_INT total_strings, total_free_strings;
1698 /* Number of bytes used by live strings. */
1700 static EMACS_INT total_string_bytes;
1702 /* Given a pointer to a Lisp_String S which is on the free-list
1703 string_free_list, return a pointer to its successor in the
1704 free-list. */
1706 #define NEXT_FREE_LISP_STRING(S) (*(struct Lisp_String **) (S))
1708 /* Return a pointer to the sdata structure belonging to Lisp string S.
1709 S must be live, i.e. S->data must not be null. S->data is actually
1710 a pointer to the `u.data' member of its sdata structure; the
1711 structure starts at a constant offset in front of that. */
1713 #define SDATA_OF_STRING(S) ((sdata *) ((S)->data - SDATA_DATA_OFFSET))
1716 #ifdef GC_CHECK_STRING_OVERRUN
1718 /* We check for overrun in string data blocks by appending a small
1719 "cookie" after each allocated string data block, and check for the
1720 presence of this cookie during GC. */
1722 #define GC_STRING_OVERRUN_COOKIE_SIZE 4
1723 static char const string_overrun_cookie[GC_STRING_OVERRUN_COOKIE_SIZE] =
1724 { '\xde', '\xad', '\xbe', '\xef' };
1726 #else
1727 #define GC_STRING_OVERRUN_COOKIE_SIZE 0
1728 #endif
1730 /* Value is the size of an sdata structure large enough to hold NBYTES
1731 bytes of string data. The value returned includes a terminating
1732 NUL byte, the size of the sdata structure, and padding. */
1734 #ifdef GC_CHECK_STRING_BYTES
1736 #define SDATA_SIZE(NBYTES) \
1737 ((SDATA_DATA_OFFSET \
1738 + (NBYTES) + 1 \
1739 + sizeof (ptrdiff_t) - 1) \
1740 & ~(sizeof (ptrdiff_t) - 1))
1742 #else /* not GC_CHECK_STRING_BYTES */
1744 /* The 'max' reserves space for the nbytes union member even when NBYTES + 1 is
1745 less than the size of that member. The 'max' is not needed when
1746 SDATA_DATA_OFFSET is a multiple of sizeof (ptrdiff_t), because then the
1747 alignment code reserves enough space. */
1749 #define SDATA_SIZE(NBYTES) \
1750 ((SDATA_DATA_OFFSET \
1751 + (SDATA_DATA_OFFSET % sizeof (ptrdiff_t) == 0 \
1752 ? NBYTES \
1753 : max (NBYTES, sizeof (ptrdiff_t) - 1)) \
1754 + 1 \
1755 + sizeof (ptrdiff_t) - 1) \
1756 & ~(sizeof (ptrdiff_t) - 1))
1758 #endif /* not GC_CHECK_STRING_BYTES */
1760 /* Extra bytes to allocate for each string. */
1762 #define GC_STRING_EXTRA (GC_STRING_OVERRUN_COOKIE_SIZE)
1764 /* Exact bound on the number of bytes in a string, not counting the
1765 terminating null. A string cannot contain more bytes than
1766 STRING_BYTES_BOUND, nor can it be so long that the size_t
1767 arithmetic in allocate_string_data would overflow while it is
1768 calculating a value to be passed to malloc. */
1769 static ptrdiff_t const STRING_BYTES_MAX =
1770 min (STRING_BYTES_BOUND,
1771 ((SIZE_MAX - XMALLOC_OVERRUN_CHECK_OVERHEAD
1772 - GC_STRING_EXTRA
1773 - offsetof (struct sblock, data)
1774 - SDATA_DATA_OFFSET)
1775 & ~(sizeof (EMACS_INT) - 1)));
1777 /* Initialize string allocation. Called from init_alloc_once. */
1779 static void
1780 init_strings (void)
1782 empty_unibyte_string = make_pure_string ("", 0, 0, 0);
1783 empty_multibyte_string = make_pure_string ("", 0, 0, 1);
1787 #ifdef GC_CHECK_STRING_BYTES
1789 static int check_string_bytes_count;
1791 /* Like STRING_BYTES, but with debugging check. Can be
1792 called during GC, so pay attention to the mark bit. */
1794 ptrdiff_t
1795 string_bytes (struct Lisp_String *s)
1797 ptrdiff_t nbytes =
1798 (s->size_byte < 0 ? s->size & ~ARRAY_MARK_FLAG : s->size_byte);
1800 if (!PURE_P (s) && s->data && nbytes != SDATA_NBYTES (SDATA_OF_STRING (s)))
1801 emacs_abort ();
1802 return nbytes;
1805 /* Check validity of Lisp strings' string_bytes member in B. */
1807 static void
1808 check_sblock (struct sblock *b)
1810 sdata *from, *end, *from_end;
1812 end = b->next_free;
1814 for (from = b->data; from < end; from = from_end)
1816 /* Compute the next FROM here because copying below may
1817 overwrite data we need to compute it. */
1818 ptrdiff_t nbytes;
1820 /* Check that the string size recorded in the string is the
1821 same as the one recorded in the sdata structure. */
1822 nbytes = SDATA_SIZE (from->string ? string_bytes (from->string)
1823 : SDATA_NBYTES (from));
1824 from_end = (sdata *) ((char *) from + nbytes + GC_STRING_EXTRA);
1829 /* Check validity of Lisp strings' string_bytes member. ALL_P
1830 means check all strings, otherwise check only most
1831 recently allocated strings. Used for hunting a bug. */
1833 static void
1834 check_string_bytes (bool all_p)
1836 if (all_p)
1838 struct sblock *b;
1840 for (b = large_sblocks; b; b = b->next)
1842 struct Lisp_String *s = b->data[0].string;
1843 if (s)
1844 string_bytes (s);
1847 for (b = oldest_sblock; b; b = b->next)
1848 check_sblock (b);
1850 else if (current_sblock)
1851 check_sblock (current_sblock);
1854 #else /* not GC_CHECK_STRING_BYTES */
1856 #define check_string_bytes(all) ((void) 0)
1858 #endif /* GC_CHECK_STRING_BYTES */
1860 #ifdef GC_CHECK_STRING_FREE_LIST
1862 /* Walk through the string free list looking for bogus next pointers.
1863 This may catch buffer overrun from a previous string. */
1865 static void
1866 check_string_free_list (void)
1868 struct Lisp_String *s;
1870 /* Pop a Lisp_String off the free-list. */
1871 s = string_free_list;
1872 while (s != NULL)
1874 if ((uintptr_t) s < 1024)
1875 emacs_abort ();
1876 s = NEXT_FREE_LISP_STRING (s);
1879 #else
1880 #define check_string_free_list()
1881 #endif
1883 /* Return a new Lisp_String. */
1885 static struct Lisp_String *
1886 allocate_string (void)
1888 struct Lisp_String *s;
1890 MALLOC_BLOCK_INPUT;
1892 /* If the free-list is empty, allocate a new string_block, and
1893 add all the Lisp_Strings in it to the free-list. */
1894 if (string_free_list == NULL)
1896 struct string_block *b = lisp_malloc (sizeof *b, MEM_TYPE_STRING);
1897 int i;
1899 b->next = string_blocks;
1900 string_blocks = b;
1902 for (i = STRING_BLOCK_SIZE - 1; i >= 0; --i)
1904 s = b->strings + i;
1905 /* Every string on a free list should have NULL data pointer. */
1906 s->data = NULL;
1907 NEXT_FREE_LISP_STRING (s) = string_free_list;
1908 string_free_list = s;
1911 total_free_strings += STRING_BLOCK_SIZE;
1914 check_string_free_list ();
1916 /* Pop a Lisp_String off the free-list. */
1917 s = string_free_list;
1918 string_free_list = NEXT_FREE_LISP_STRING (s);
1920 MALLOC_UNBLOCK_INPUT;
1922 --total_free_strings;
1923 ++total_strings;
1924 ++strings_consed;
1925 consing_since_gc += sizeof *s;
1927 #ifdef GC_CHECK_STRING_BYTES
1928 if (!noninteractive)
1930 if (++check_string_bytes_count == 200)
1932 check_string_bytes_count = 0;
1933 check_string_bytes (1);
1935 else
1936 check_string_bytes (0);
1938 #endif /* GC_CHECK_STRING_BYTES */
1940 return s;
1944 /* Set up Lisp_String S for holding NCHARS characters, NBYTES bytes,
1945 plus a NUL byte at the end. Allocate an sdata structure for S, and
1946 set S->data to its `u.data' member. Store a NUL byte at the end of
1947 S->data. Set S->size to NCHARS and S->size_byte to NBYTES. Free
1948 S->data if it was initially non-null. */
1950 void
1951 allocate_string_data (struct Lisp_String *s,
1952 EMACS_INT nchars, EMACS_INT nbytes)
1954 sdata *data, *old_data;
1955 struct sblock *b;
1956 ptrdiff_t needed, old_nbytes;
1958 if (STRING_BYTES_MAX < nbytes)
1959 string_overflow ();
1961 /* Determine the number of bytes needed to store NBYTES bytes
1962 of string data. */
1963 needed = SDATA_SIZE (nbytes);
1964 if (s->data)
1966 old_data = SDATA_OF_STRING (s);
1967 old_nbytes = STRING_BYTES (s);
1969 else
1970 old_data = NULL;
1972 MALLOC_BLOCK_INPUT;
1974 if (nbytes > LARGE_STRING_BYTES)
1976 size_t size = offsetof (struct sblock, data) + needed;
1978 #ifdef DOUG_LEA_MALLOC
1979 if (!mmap_lisp_allowed_p ())
1980 mallopt (M_MMAP_MAX, 0);
1981 #endif
1983 b = lisp_malloc (size + GC_STRING_EXTRA, MEM_TYPE_NON_LISP);
1985 #ifdef DOUG_LEA_MALLOC
1986 if (!mmap_lisp_allowed_p ())
1987 mallopt (M_MMAP_MAX, MMAP_MAX_AREAS);
1988 #endif
1990 b->next_free = b->data;
1991 b->data[0].string = NULL;
1992 b->next = large_sblocks;
1993 large_sblocks = b;
1995 else if (current_sblock == NULL
1996 || (((char *) current_sblock + SBLOCK_SIZE
1997 - (char *) current_sblock->next_free)
1998 < (needed + GC_STRING_EXTRA)))
2000 /* Not enough room in the current sblock. */
2001 b = lisp_malloc (SBLOCK_SIZE, MEM_TYPE_NON_LISP);
2002 b->next_free = b->data;
2003 b->data[0].string = NULL;
2004 b->next = NULL;
2006 if (current_sblock)
2007 current_sblock->next = b;
2008 else
2009 oldest_sblock = b;
2010 current_sblock = b;
2012 else
2013 b = current_sblock;
2015 data = b->next_free;
2016 b->next_free = (sdata *) ((char *) data + needed + GC_STRING_EXTRA);
2018 MALLOC_UNBLOCK_INPUT;
2020 data->string = s;
2021 s->data = SDATA_DATA (data);
2022 #ifdef GC_CHECK_STRING_BYTES
2023 SDATA_NBYTES (data) = nbytes;
2024 #endif
2025 s->size = nchars;
2026 s->size_byte = nbytes;
2027 s->data[nbytes] = '\0';
2028 #ifdef GC_CHECK_STRING_OVERRUN
2029 memcpy ((char *) data + needed, string_overrun_cookie,
2030 GC_STRING_OVERRUN_COOKIE_SIZE);
2031 #endif
2033 /* Note that Faset may call to this function when S has already data
2034 assigned. In this case, mark data as free by setting it's string
2035 back-pointer to null, and record the size of the data in it. */
2036 if (old_data)
2038 SDATA_NBYTES (old_data) = old_nbytes;
2039 old_data->string = NULL;
2042 consing_since_gc += needed;
2046 /* Sweep and compact strings. */
2048 NO_INLINE /* For better stack traces */
2049 static void
2050 sweep_strings (void)
2052 struct string_block *b, *next;
2053 struct string_block *live_blocks = NULL;
2055 string_free_list = NULL;
2056 total_strings = total_free_strings = 0;
2057 total_string_bytes = 0;
2059 /* Scan strings_blocks, free Lisp_Strings that aren't marked. */
2060 for (b = string_blocks; b; b = next)
2062 int i, nfree = 0;
2063 struct Lisp_String *free_list_before = string_free_list;
2065 next = b->next;
2067 for (i = 0; i < STRING_BLOCK_SIZE; ++i)
2069 struct Lisp_String *s = b->strings + i;
2071 if (s->data)
2073 /* String was not on free-list before. */
2074 if (STRING_MARKED_P (s))
2076 /* String is live; unmark it and its intervals. */
2077 UNMARK_STRING (s);
2079 /* Do not use string_(set|get)_intervals here. */
2080 s->intervals = balance_intervals (s->intervals);
2082 ++total_strings;
2083 total_string_bytes += STRING_BYTES (s);
2085 else
2087 /* String is dead. Put it on the free-list. */
2088 sdata *data = SDATA_OF_STRING (s);
2090 /* Save the size of S in its sdata so that we know
2091 how large that is. Reset the sdata's string
2092 back-pointer so that we know it's free. */
2093 #ifdef GC_CHECK_STRING_BYTES
2094 if (string_bytes (s) != SDATA_NBYTES (data))
2095 emacs_abort ();
2096 #else
2097 data->n.nbytes = STRING_BYTES (s);
2098 #endif
2099 data->string = NULL;
2101 /* Reset the strings's `data' member so that we
2102 know it's free. */
2103 s->data = NULL;
2105 /* Put the string on the free-list. */
2106 NEXT_FREE_LISP_STRING (s) = string_free_list;
2107 string_free_list = s;
2108 ++nfree;
2111 else
2113 /* S was on the free-list before. Put it there again. */
2114 NEXT_FREE_LISP_STRING (s) = string_free_list;
2115 string_free_list = s;
2116 ++nfree;
2120 /* Free blocks that contain free Lisp_Strings only, except
2121 the first two of them. */
2122 if (nfree == STRING_BLOCK_SIZE
2123 && total_free_strings > STRING_BLOCK_SIZE)
2125 lisp_free (b);
2126 string_free_list = free_list_before;
2128 else
2130 total_free_strings += nfree;
2131 b->next = live_blocks;
2132 live_blocks = b;
2136 check_string_free_list ();
2138 string_blocks = live_blocks;
2139 free_large_strings ();
2140 compact_small_strings ();
2142 check_string_free_list ();
2146 /* Free dead large strings. */
2148 static void
2149 free_large_strings (void)
2151 struct sblock *b, *next;
2152 struct sblock *live_blocks = NULL;
2154 for (b = large_sblocks; b; b = next)
2156 next = b->next;
2158 if (b->data[0].string == NULL)
2159 lisp_free (b);
2160 else
2162 b->next = live_blocks;
2163 live_blocks = b;
2167 large_sblocks = live_blocks;
2171 /* Compact data of small strings. Free sblocks that don't contain
2172 data of live strings after compaction. */
2174 static void
2175 compact_small_strings (void)
2177 struct sblock *b, *tb, *next;
2178 sdata *from, *to, *end, *tb_end;
2179 sdata *to_end, *from_end;
2181 /* TB is the sblock we copy to, TO is the sdata within TB we copy
2182 to, and TB_END is the end of TB. */
2183 tb = oldest_sblock;
2184 tb_end = (sdata *) ((char *) tb + SBLOCK_SIZE);
2185 to = tb->data;
2187 /* Step through the blocks from the oldest to the youngest. We
2188 expect that old blocks will stabilize over time, so that less
2189 copying will happen this way. */
2190 for (b = oldest_sblock; b; b = b->next)
2192 end = b->next_free;
2193 eassert ((char *) end <= (char *) b + SBLOCK_SIZE);
2195 for (from = b->data; from < end; from = from_end)
2197 /* Compute the next FROM here because copying below may
2198 overwrite data we need to compute it. */
2199 ptrdiff_t nbytes;
2200 struct Lisp_String *s = from->string;
2202 #ifdef GC_CHECK_STRING_BYTES
2203 /* Check that the string size recorded in the string is the
2204 same as the one recorded in the sdata structure. */
2205 if (s && string_bytes (s) != SDATA_NBYTES (from))
2206 emacs_abort ();
2207 #endif /* GC_CHECK_STRING_BYTES */
2209 nbytes = s ? STRING_BYTES (s) : SDATA_NBYTES (from);
2210 eassert (nbytes <= LARGE_STRING_BYTES);
2212 nbytes = SDATA_SIZE (nbytes);
2213 from_end = (sdata *) ((char *) from + nbytes + GC_STRING_EXTRA);
2215 #ifdef GC_CHECK_STRING_OVERRUN
2216 if (memcmp (string_overrun_cookie,
2217 (char *) from_end - GC_STRING_OVERRUN_COOKIE_SIZE,
2218 GC_STRING_OVERRUN_COOKIE_SIZE))
2219 emacs_abort ();
2220 #endif
2222 /* Non-NULL S means it's alive. Copy its data. */
2223 if (s)
2225 /* If TB is full, proceed with the next sblock. */
2226 to_end = (sdata *) ((char *) to + nbytes + GC_STRING_EXTRA);
2227 if (to_end > tb_end)
2229 tb->next_free = to;
2230 tb = tb->next;
2231 tb_end = (sdata *) ((char *) tb + SBLOCK_SIZE);
2232 to = tb->data;
2233 to_end = (sdata *) ((char *) to + nbytes + GC_STRING_EXTRA);
2236 /* Copy, and update the string's `data' pointer. */
2237 if (from != to)
2239 eassert (tb != b || to < from);
2240 memmove (to, from, nbytes + GC_STRING_EXTRA);
2241 to->string->data = SDATA_DATA (to);
2244 /* Advance past the sdata we copied to. */
2245 to = to_end;
2250 /* The rest of the sblocks following TB don't contain live data, so
2251 we can free them. */
2252 for (b = tb->next; b; b = next)
2254 next = b->next;
2255 lisp_free (b);
2258 tb->next_free = to;
2259 tb->next = NULL;
2260 current_sblock = tb;
2263 void
2264 string_overflow (void)
2266 error ("Maximum string size exceeded");
2269 DEFUN ("make-string", Fmake_string, Smake_string, 2, 2, 0,
2270 doc: /* Return a newly created string of length LENGTH, with INIT in each element.
2271 LENGTH must be an integer.
2272 INIT must be an integer that represents a character. */)
2273 (Lisp_Object length, Lisp_Object init)
2275 register Lisp_Object val;
2276 int c;
2277 EMACS_INT nbytes;
2279 CHECK_NATNUM (length);
2280 CHECK_CHARACTER (init);
2282 c = XFASTINT (init);
2283 if (ASCII_CHAR_P (c))
2285 nbytes = XINT (length);
2286 val = make_uninit_string (nbytes);
2287 if (nbytes)
2289 memset (SDATA (val), c, nbytes);
2290 SDATA (val)[nbytes] = 0;
2293 else
2295 unsigned char str[MAX_MULTIBYTE_LENGTH];
2296 ptrdiff_t len = CHAR_STRING (c, str);
2297 EMACS_INT string_len = XINT (length);
2298 unsigned char *p, *beg, *end;
2300 if (INT_MULTIPLY_WRAPV (len, string_len, &nbytes))
2301 string_overflow ();
2302 val = make_uninit_multibyte_string (string_len, nbytes);
2303 for (beg = SDATA (val), p = beg, end = beg + nbytes; p < end; p += len)
2305 /* First time we just copy `str' to the data of `val'. */
2306 if (p == beg)
2307 memcpy (p, str, len);
2308 else
2310 /* Next time we copy largest possible chunk from
2311 initialized to uninitialized part of `val'. */
2312 len = min (p - beg, end - p);
2313 memcpy (p, beg, len);
2316 if (nbytes)
2317 *p = 0;
2320 return val;
2323 /* Fill A with 1 bits if INIT is non-nil, and with 0 bits otherwise.
2324 Return A. */
2326 Lisp_Object
2327 bool_vector_fill (Lisp_Object a, Lisp_Object init)
2329 EMACS_INT nbits = bool_vector_size (a);
2330 if (0 < nbits)
2332 unsigned char *data = bool_vector_uchar_data (a);
2333 int pattern = NILP (init) ? 0 : (1 << BOOL_VECTOR_BITS_PER_CHAR) - 1;
2334 ptrdiff_t nbytes = bool_vector_bytes (nbits);
2335 int last_mask = ~ (~0u << ((nbits - 1) % BOOL_VECTOR_BITS_PER_CHAR + 1));
2336 memset (data, pattern, nbytes - 1);
2337 data[nbytes - 1] = pattern & last_mask;
2339 return a;
2342 /* Return a newly allocated, uninitialized bool vector of size NBITS. */
2344 Lisp_Object
2345 make_uninit_bool_vector (EMACS_INT nbits)
2347 Lisp_Object val;
2348 EMACS_INT words = bool_vector_words (nbits);
2349 EMACS_INT word_bytes = words * sizeof (bits_word);
2350 EMACS_INT needed_elements = ((bool_header_size - header_size + word_bytes
2351 + word_size - 1)
2352 / word_size);
2353 struct Lisp_Bool_Vector *p
2354 = (struct Lisp_Bool_Vector *) allocate_vector (needed_elements);
2355 XSETVECTOR (val, p);
2356 XSETPVECTYPESIZE (XVECTOR (val), PVEC_BOOL_VECTOR, 0, 0);
2357 p->size = nbits;
2359 /* Clear padding at the end. */
2360 if (words)
2361 p->data[words - 1] = 0;
2363 return val;
2366 DEFUN ("make-bool-vector", Fmake_bool_vector, Smake_bool_vector, 2, 2, 0,
2367 doc: /* Return a new bool-vector of length LENGTH, using INIT for each element.
2368 LENGTH must be a number. INIT matters only in whether it is t or nil. */)
2369 (Lisp_Object length, Lisp_Object init)
2371 Lisp_Object val;
2373 CHECK_NATNUM (length);
2374 val = make_uninit_bool_vector (XFASTINT (length));
2375 return bool_vector_fill (val, init);
2378 DEFUN ("bool-vector", Fbool_vector, Sbool_vector, 0, MANY, 0,
2379 doc: /* Return a new bool-vector with specified arguments as elements.
2380 Any number of arguments, even zero arguments, are allowed.
2381 usage: (bool-vector &rest OBJECTS) */)
2382 (ptrdiff_t nargs, Lisp_Object *args)
2384 ptrdiff_t i;
2385 Lisp_Object vector;
2387 vector = make_uninit_bool_vector (nargs);
2388 for (i = 0; i < nargs; i++)
2389 bool_vector_set (vector, i, !NILP (args[i]));
2391 return vector;
2394 /* Make a string from NBYTES bytes at CONTENTS, and compute the number
2395 of characters from the contents. This string may be unibyte or
2396 multibyte, depending on the contents. */
2398 Lisp_Object
2399 make_string (const char *contents, ptrdiff_t nbytes)
2401 register Lisp_Object val;
2402 ptrdiff_t nchars, multibyte_nbytes;
2404 parse_str_as_multibyte ((const unsigned char *) contents, nbytes,
2405 &nchars, &multibyte_nbytes);
2406 if (nbytes == nchars || nbytes != multibyte_nbytes)
2407 /* CONTENTS contains no multibyte sequences or contains an invalid
2408 multibyte sequence. We must make unibyte string. */
2409 val = make_unibyte_string (contents, nbytes);
2410 else
2411 val = make_multibyte_string (contents, nchars, nbytes);
2412 return val;
2415 /* Make a unibyte string from LENGTH bytes at CONTENTS. */
2417 Lisp_Object
2418 make_unibyte_string (const char *contents, ptrdiff_t length)
2420 register Lisp_Object val;
2421 val = make_uninit_string (length);
2422 memcpy (SDATA (val), contents, length);
2423 return val;
2427 /* Make a multibyte string from NCHARS characters occupying NBYTES
2428 bytes at CONTENTS. */
2430 Lisp_Object
2431 make_multibyte_string (const char *contents,
2432 ptrdiff_t nchars, ptrdiff_t nbytes)
2434 register Lisp_Object val;
2435 val = make_uninit_multibyte_string (nchars, nbytes);
2436 memcpy (SDATA (val), contents, nbytes);
2437 return val;
2441 /* Make a string from NCHARS characters occupying NBYTES bytes at
2442 CONTENTS. It is a multibyte string if NBYTES != NCHARS. */
2444 Lisp_Object
2445 make_string_from_bytes (const char *contents,
2446 ptrdiff_t nchars, ptrdiff_t nbytes)
2448 register Lisp_Object val;
2449 val = make_uninit_multibyte_string (nchars, nbytes);
2450 memcpy (SDATA (val), contents, nbytes);
2451 if (SBYTES (val) == SCHARS (val))
2452 STRING_SET_UNIBYTE (val);
2453 return val;
2457 /* Make a string from NCHARS characters occupying NBYTES bytes at
2458 CONTENTS. The argument MULTIBYTE controls whether to label the
2459 string as multibyte. If NCHARS is negative, it counts the number of
2460 characters by itself. */
2462 Lisp_Object
2463 make_specified_string (const char *contents,
2464 ptrdiff_t nchars, ptrdiff_t nbytes, bool multibyte)
2466 Lisp_Object val;
2468 if (nchars < 0)
2470 if (multibyte)
2471 nchars = multibyte_chars_in_text ((const unsigned char *) contents,
2472 nbytes);
2473 else
2474 nchars = nbytes;
2476 val = make_uninit_multibyte_string (nchars, nbytes);
2477 memcpy (SDATA (val), contents, nbytes);
2478 if (!multibyte)
2479 STRING_SET_UNIBYTE (val);
2480 return val;
2484 /* Return a unibyte Lisp_String set up to hold LENGTH characters
2485 occupying LENGTH bytes. */
2487 Lisp_Object
2488 make_uninit_string (EMACS_INT length)
2490 Lisp_Object val;
2492 if (!length)
2493 return empty_unibyte_string;
2494 val = make_uninit_multibyte_string (length, length);
2495 STRING_SET_UNIBYTE (val);
2496 return val;
2500 /* Return a multibyte Lisp_String set up to hold NCHARS characters
2501 which occupy NBYTES bytes. */
2503 Lisp_Object
2504 make_uninit_multibyte_string (EMACS_INT nchars, EMACS_INT nbytes)
2506 Lisp_Object string;
2507 struct Lisp_String *s;
2509 if (nchars < 0)
2510 emacs_abort ();
2511 if (!nbytes)
2512 return empty_multibyte_string;
2514 s = allocate_string ();
2515 s->intervals = NULL;
2516 allocate_string_data (s, nchars, nbytes);
2517 XSETSTRING (string, s);
2518 string_chars_consed += nbytes;
2519 return string;
2522 /* Print arguments to BUF according to a FORMAT, then return
2523 a Lisp_String initialized with the data from BUF. */
2525 Lisp_Object
2526 make_formatted_string (char *buf, const char *format, ...)
2528 va_list ap;
2529 int length;
2531 va_start (ap, format);
2532 length = vsprintf (buf, format, ap);
2533 va_end (ap);
2534 return make_string (buf, length);
2538 /***********************************************************************
2539 Float Allocation
2540 ***********************************************************************/
2542 /* We store float cells inside of float_blocks, allocating a new
2543 float_block with malloc whenever necessary. Float cells reclaimed
2544 by GC are put on a free list to be reallocated before allocating
2545 any new float cells from the latest float_block. */
2547 #define FLOAT_BLOCK_SIZE \
2548 (((BLOCK_BYTES - sizeof (struct float_block *) \
2549 /* The compiler might add padding at the end. */ \
2550 - (sizeof (struct Lisp_Float) - sizeof (bits_word))) * CHAR_BIT) \
2551 / (sizeof (struct Lisp_Float) * CHAR_BIT + 1))
2553 #define GETMARKBIT(block,n) \
2554 (((block)->gcmarkbits[(n) / BITS_PER_BITS_WORD] \
2555 >> ((n) % BITS_PER_BITS_WORD)) \
2556 & 1)
2558 #define SETMARKBIT(block,n) \
2559 ((block)->gcmarkbits[(n) / BITS_PER_BITS_WORD] \
2560 |= (bits_word) 1 << ((n) % BITS_PER_BITS_WORD))
2562 #define UNSETMARKBIT(block,n) \
2563 ((block)->gcmarkbits[(n) / BITS_PER_BITS_WORD] \
2564 &= ~((bits_word) 1 << ((n) % BITS_PER_BITS_WORD)))
2566 #define FLOAT_BLOCK(fptr) \
2567 ((struct float_block *) (((uintptr_t) (fptr)) & ~(BLOCK_ALIGN - 1)))
2569 #define FLOAT_INDEX(fptr) \
2570 ((((uintptr_t) (fptr)) & (BLOCK_ALIGN - 1)) / sizeof (struct Lisp_Float))
2572 struct float_block
2574 /* Place `floats' at the beginning, to ease up FLOAT_INDEX's job. */
2575 struct Lisp_Float floats[FLOAT_BLOCK_SIZE];
2576 bits_word gcmarkbits[1 + FLOAT_BLOCK_SIZE / BITS_PER_BITS_WORD];
2577 struct float_block *next;
2580 #define FLOAT_MARKED_P(fptr) \
2581 GETMARKBIT (FLOAT_BLOCK (fptr), FLOAT_INDEX ((fptr)))
2583 #define FLOAT_MARK(fptr) \
2584 SETMARKBIT (FLOAT_BLOCK (fptr), FLOAT_INDEX ((fptr)))
2586 #define FLOAT_UNMARK(fptr) \
2587 UNSETMARKBIT (FLOAT_BLOCK (fptr), FLOAT_INDEX ((fptr)))
2589 /* Current float_block. */
2591 static struct float_block *float_block;
2593 /* Index of first unused Lisp_Float in the current float_block. */
2595 static int float_block_index = FLOAT_BLOCK_SIZE;
2597 /* Free-list of Lisp_Floats. */
2599 static struct Lisp_Float *float_free_list;
2601 /* Return a new float object with value FLOAT_VALUE. */
2603 Lisp_Object
2604 make_float (double float_value)
2606 register Lisp_Object val;
2608 MALLOC_BLOCK_INPUT;
2610 if (float_free_list)
2612 /* We use the data field for chaining the free list
2613 so that we won't use the same field that has the mark bit. */
2614 XSETFLOAT (val, float_free_list);
2615 float_free_list = float_free_list->u.chain;
2617 else
2619 if (float_block_index == FLOAT_BLOCK_SIZE)
2621 struct float_block *new
2622 = lisp_align_malloc (sizeof *new, MEM_TYPE_FLOAT);
2623 new->next = float_block;
2624 memset (new->gcmarkbits, 0, sizeof new->gcmarkbits);
2625 float_block = new;
2626 float_block_index = 0;
2627 total_free_floats += FLOAT_BLOCK_SIZE;
2629 XSETFLOAT (val, &float_block->floats[float_block_index]);
2630 float_block_index++;
2633 MALLOC_UNBLOCK_INPUT;
2635 XFLOAT_INIT (val, float_value);
2636 eassert (!FLOAT_MARKED_P (XFLOAT (val)));
2637 consing_since_gc += sizeof (struct Lisp_Float);
2638 floats_consed++;
2639 total_free_floats--;
2640 return val;
2645 /***********************************************************************
2646 Cons Allocation
2647 ***********************************************************************/
2649 /* We store cons cells inside of cons_blocks, allocating a new
2650 cons_block with malloc whenever necessary. Cons cells reclaimed by
2651 GC are put on a free list to be reallocated before allocating
2652 any new cons cells from the latest cons_block. */
2654 #define CONS_BLOCK_SIZE \
2655 (((BLOCK_BYTES - sizeof (struct cons_block *) \
2656 /* The compiler might add padding at the end. */ \
2657 - (sizeof (struct Lisp_Cons) - sizeof (bits_word))) * CHAR_BIT) \
2658 / (sizeof (struct Lisp_Cons) * CHAR_BIT + 1))
2660 #define CONS_BLOCK(fptr) \
2661 ((struct cons_block *) ((uintptr_t) (fptr) & ~(BLOCK_ALIGN - 1)))
2663 #define CONS_INDEX(fptr) \
2664 (((uintptr_t) (fptr) & (BLOCK_ALIGN - 1)) / sizeof (struct Lisp_Cons))
2666 struct cons_block
2668 /* Place `conses' at the beginning, to ease up CONS_INDEX's job. */
2669 struct Lisp_Cons conses[CONS_BLOCK_SIZE];
2670 bits_word gcmarkbits[1 + CONS_BLOCK_SIZE / BITS_PER_BITS_WORD];
2671 struct cons_block *next;
2674 #define CONS_MARKED_P(fptr) \
2675 GETMARKBIT (CONS_BLOCK (fptr), CONS_INDEX ((fptr)))
2677 #define CONS_MARK(fptr) \
2678 SETMARKBIT (CONS_BLOCK (fptr), CONS_INDEX ((fptr)))
2680 #define CONS_UNMARK(fptr) \
2681 UNSETMARKBIT (CONS_BLOCK (fptr), CONS_INDEX ((fptr)))
2683 /* Current cons_block. */
2685 static struct cons_block *cons_block;
2687 /* Index of first unused Lisp_Cons in the current block. */
2689 static int cons_block_index = CONS_BLOCK_SIZE;
2691 /* Free-list of Lisp_Cons structures. */
2693 static struct Lisp_Cons *cons_free_list;
2695 /* Explicitly free a cons cell by putting it on the free-list. */
2697 void
2698 free_cons (struct Lisp_Cons *ptr)
2700 ptr->u.chain = cons_free_list;
2701 ptr->car = Vdead;
2702 cons_free_list = ptr;
2703 consing_since_gc -= sizeof *ptr;
2704 total_free_conses++;
2707 DEFUN ("cons", Fcons, Scons, 2, 2, 0,
2708 doc: /* Create a new cons, give it CAR and CDR as components, and return it. */)
2709 (Lisp_Object car, Lisp_Object cdr)
2711 register Lisp_Object val;
2713 MALLOC_BLOCK_INPUT;
2715 if (cons_free_list)
2717 /* We use the cdr for chaining the free list
2718 so that we won't use the same field that has the mark bit. */
2719 XSETCONS (val, cons_free_list);
2720 cons_free_list = cons_free_list->u.chain;
2722 else
2724 if (cons_block_index == CONS_BLOCK_SIZE)
2726 struct cons_block *new
2727 = lisp_align_malloc (sizeof *new, MEM_TYPE_CONS);
2728 memset (new->gcmarkbits, 0, sizeof new->gcmarkbits);
2729 new->next = cons_block;
2730 cons_block = new;
2731 cons_block_index = 0;
2732 total_free_conses += CONS_BLOCK_SIZE;
2734 XSETCONS (val, &cons_block->conses[cons_block_index]);
2735 cons_block_index++;
2738 MALLOC_UNBLOCK_INPUT;
2740 XSETCAR (val, car);
2741 XSETCDR (val, cdr);
2742 eassert (!CONS_MARKED_P (XCONS (val)));
2743 consing_since_gc += sizeof (struct Lisp_Cons);
2744 total_free_conses--;
2745 cons_cells_consed++;
2746 return val;
2749 #ifdef GC_CHECK_CONS_LIST
2750 /* Get an error now if there's any junk in the cons free list. */
2751 void
2752 check_cons_list (void)
2754 struct Lisp_Cons *tail = cons_free_list;
2756 while (tail)
2757 tail = tail->u.chain;
2759 #endif
2761 /* Make a list of 1, 2, 3, 4 or 5 specified objects. */
2763 Lisp_Object
2764 list1 (Lisp_Object arg1)
2766 return Fcons (arg1, Qnil);
2769 Lisp_Object
2770 list2 (Lisp_Object arg1, Lisp_Object arg2)
2772 return Fcons (arg1, Fcons (arg2, Qnil));
2776 Lisp_Object
2777 list3 (Lisp_Object arg1, Lisp_Object arg2, Lisp_Object arg3)
2779 return Fcons (arg1, Fcons (arg2, Fcons (arg3, Qnil)));
2783 Lisp_Object
2784 list4 (Lisp_Object arg1, Lisp_Object arg2, Lisp_Object arg3, Lisp_Object arg4)
2786 return Fcons (arg1, Fcons (arg2, Fcons (arg3, Fcons (arg4, Qnil))));
2790 Lisp_Object
2791 list5 (Lisp_Object arg1, Lisp_Object arg2, Lisp_Object arg3, Lisp_Object arg4, Lisp_Object arg5)
2793 return Fcons (arg1, Fcons (arg2, Fcons (arg3, Fcons (arg4,
2794 Fcons (arg5, Qnil)))));
2797 /* Make a list of COUNT Lisp_Objects, where ARG is the
2798 first one. Allocate conses from pure space if TYPE
2799 is CONSTYPE_PURE, or allocate as usual if type is CONSTYPE_HEAP. */
2801 Lisp_Object
2802 listn (enum constype type, ptrdiff_t count, Lisp_Object arg, ...)
2804 Lisp_Object (*cons) (Lisp_Object, Lisp_Object);
2805 switch (type)
2807 case CONSTYPE_PURE: cons = pure_cons; break;
2808 case CONSTYPE_HEAP: cons = Fcons; break;
2809 default: emacs_abort ();
2812 eassume (0 < count);
2813 Lisp_Object val = cons (arg, Qnil);
2814 Lisp_Object tail = val;
2816 va_list ap;
2817 va_start (ap, arg);
2818 for (ptrdiff_t i = 1; i < count; i++)
2820 Lisp_Object elem = cons (va_arg (ap, Lisp_Object), Qnil);
2821 XSETCDR (tail, elem);
2822 tail = elem;
2824 va_end (ap);
2826 return val;
2829 DEFUN ("list", Flist, Slist, 0, MANY, 0,
2830 doc: /* Return a newly created list with specified arguments as elements.
2831 Any number of arguments, even zero arguments, are allowed.
2832 usage: (list &rest OBJECTS) */)
2833 (ptrdiff_t nargs, Lisp_Object *args)
2835 register Lisp_Object val;
2836 val = Qnil;
2838 while (nargs > 0)
2840 nargs--;
2841 val = Fcons (args[nargs], val);
2843 return val;
2847 DEFUN ("make-list", Fmake_list, Smake_list, 2, 2, 0,
2848 doc: /* Return a newly created list of length LENGTH, with each element being INIT. */)
2849 (register Lisp_Object length, Lisp_Object init)
2851 register Lisp_Object val;
2852 register EMACS_INT size;
2854 CHECK_NATNUM (length);
2855 size = XFASTINT (length);
2857 val = Qnil;
2858 while (size > 0)
2860 val = Fcons (init, val);
2861 --size;
2863 if (size > 0)
2865 val = Fcons (init, val);
2866 --size;
2868 if (size > 0)
2870 val = Fcons (init, val);
2871 --size;
2873 if (size > 0)
2875 val = Fcons (init, val);
2876 --size;
2878 if (size > 0)
2880 val = Fcons (init, val);
2881 --size;
2887 QUIT;
2890 return val;
2895 /***********************************************************************
2896 Vector Allocation
2897 ***********************************************************************/
2899 /* Sometimes a vector's contents are merely a pointer internally used
2900 in vector allocation code. On the rare platforms where a null
2901 pointer cannot be tagged, represent it with a Lisp 0.
2902 Usually you don't want to touch this. */
2904 static struct Lisp_Vector *
2905 next_vector (struct Lisp_Vector *v)
2907 return XUNTAG (v->contents[0], Lisp_Int0);
2910 static void
2911 set_next_vector (struct Lisp_Vector *v, struct Lisp_Vector *p)
2913 v->contents[0] = make_lisp_ptr (p, Lisp_Int0);
2916 /* This value is balanced well enough to avoid too much internal overhead
2917 for the most common cases; it's not required to be a power of two, but
2918 it's expected to be a mult-of-ROUNDUP_SIZE (see below). */
2920 #define VECTOR_BLOCK_SIZE 4096
2922 enum
2924 /* Alignment of struct Lisp_Vector objects. */
2925 vector_alignment = COMMON_MULTIPLE (ALIGNOF_STRUCT_LISP_VECTOR,
2926 GCALIGNMENT),
2928 /* Vector size requests are a multiple of this. */
2929 roundup_size = COMMON_MULTIPLE (vector_alignment, word_size)
2932 /* Verify assumptions described above. */
2933 verify ((VECTOR_BLOCK_SIZE % roundup_size) == 0);
2934 verify (VECTOR_BLOCK_SIZE <= (1 << PSEUDOVECTOR_SIZE_BITS));
2936 /* Round up X to nearest mult-of-ROUNDUP_SIZE --- use at compile time. */
2937 #define vroundup_ct(x) ROUNDUP (x, roundup_size)
2938 /* Round up X to nearest mult-of-ROUNDUP_SIZE --- use at runtime. */
2939 #define vroundup(x) (eassume ((x) >= 0), vroundup_ct (x))
2941 /* Rounding helps to maintain alignment constraints if USE_LSB_TAG. */
2943 #define VECTOR_BLOCK_BYTES (VECTOR_BLOCK_SIZE - vroundup_ct (sizeof (void *)))
2945 /* Size of the minimal vector allocated from block. */
2947 #define VBLOCK_BYTES_MIN vroundup_ct (header_size + sizeof (Lisp_Object))
2949 /* Size of the largest vector allocated from block. */
2951 #define VBLOCK_BYTES_MAX \
2952 vroundup ((VECTOR_BLOCK_BYTES / 2) - word_size)
2954 /* We maintain one free list for each possible block-allocated
2955 vector size, and this is the number of free lists we have. */
2957 #define VECTOR_MAX_FREE_LIST_INDEX \
2958 ((VECTOR_BLOCK_BYTES - VBLOCK_BYTES_MIN) / roundup_size + 1)
2960 /* Common shortcut to advance vector pointer over a block data. */
2962 #define ADVANCE(v, nbytes) ((struct Lisp_Vector *) ((char *) (v) + (nbytes)))
2964 /* Common shortcut to calculate NBYTES-vector index in VECTOR_FREE_LISTS. */
2966 #define VINDEX(nbytes) (((nbytes) - VBLOCK_BYTES_MIN) / roundup_size)
2968 /* Common shortcut to setup vector on a free list. */
2970 #define SETUP_ON_FREE_LIST(v, nbytes, tmp) \
2971 do { \
2972 (tmp) = ((nbytes - header_size) / word_size); \
2973 XSETPVECTYPESIZE (v, PVEC_FREE, 0, (tmp)); \
2974 eassert ((nbytes) % roundup_size == 0); \
2975 (tmp) = VINDEX (nbytes); \
2976 eassert ((tmp) < VECTOR_MAX_FREE_LIST_INDEX); \
2977 set_next_vector (v, vector_free_lists[tmp]); \
2978 vector_free_lists[tmp] = (v); \
2979 total_free_vector_slots += (nbytes) / word_size; \
2980 } while (0)
2982 /* This internal type is used to maintain the list of large vectors
2983 which are allocated at their own, e.g. outside of vector blocks.
2985 struct large_vector itself cannot contain a struct Lisp_Vector, as
2986 the latter contains a flexible array member and C99 does not allow
2987 such structs to be nested. Instead, each struct large_vector
2988 object LV is followed by a struct Lisp_Vector, which is at offset
2989 large_vector_offset from LV, and whose address is therefore
2990 large_vector_vec (&LV). */
2992 struct large_vector
2994 struct large_vector *next;
2997 enum
2999 large_vector_offset = ROUNDUP (sizeof (struct large_vector), vector_alignment)
3002 static struct Lisp_Vector *
3003 large_vector_vec (struct large_vector *p)
3005 return (struct Lisp_Vector *) ((char *) p + large_vector_offset);
3008 /* This internal type is used to maintain an underlying storage
3009 for small vectors. */
3011 struct vector_block
3013 char data[VECTOR_BLOCK_BYTES];
3014 struct vector_block *next;
3017 /* Chain of vector blocks. */
3019 static struct vector_block *vector_blocks;
3021 /* Vector free lists, where NTH item points to a chain of free
3022 vectors of the same NBYTES size, so NTH == VINDEX (NBYTES). */
3024 static struct Lisp_Vector *vector_free_lists[VECTOR_MAX_FREE_LIST_INDEX];
3026 /* Singly-linked list of large vectors. */
3028 static struct large_vector *large_vectors;
3030 /* The only vector with 0 slots, allocated from pure space. */
3032 Lisp_Object zero_vector;
3034 /* Number of live vectors. */
3036 static EMACS_INT total_vectors;
3038 /* Total size of live and free vectors, in Lisp_Object units. */
3040 static EMACS_INT total_vector_slots, total_free_vector_slots;
3042 /* Get a new vector block. */
3044 static struct vector_block *
3045 allocate_vector_block (void)
3047 struct vector_block *block = xmalloc (sizeof *block);
3049 #ifndef GC_MALLOC_CHECK
3050 mem_insert (block->data, block->data + VECTOR_BLOCK_BYTES,
3051 MEM_TYPE_VECTOR_BLOCK);
3052 #endif
3054 block->next = vector_blocks;
3055 vector_blocks = block;
3056 return block;
3059 /* Called once to initialize vector allocation. */
3061 static void
3062 init_vectors (void)
3064 zero_vector = make_pure_vector (0);
3067 /* Allocate vector from a vector block. */
3069 static struct Lisp_Vector *
3070 allocate_vector_from_block (size_t nbytes)
3072 struct Lisp_Vector *vector;
3073 struct vector_block *block;
3074 size_t index, restbytes;
3076 eassert (VBLOCK_BYTES_MIN <= nbytes && nbytes <= VBLOCK_BYTES_MAX);
3077 eassert (nbytes % roundup_size == 0);
3079 /* First, try to allocate from a free list
3080 containing vectors of the requested size. */
3081 index = VINDEX (nbytes);
3082 if (vector_free_lists[index])
3084 vector = vector_free_lists[index];
3085 vector_free_lists[index] = next_vector (vector);
3086 total_free_vector_slots -= nbytes / word_size;
3087 return vector;
3090 /* Next, check free lists containing larger vectors. Since
3091 we will split the result, we should have remaining space
3092 large enough to use for one-slot vector at least. */
3093 for (index = VINDEX (nbytes + VBLOCK_BYTES_MIN);
3094 index < VECTOR_MAX_FREE_LIST_INDEX; index++)
3095 if (vector_free_lists[index])
3097 /* This vector is larger than requested. */
3098 vector = vector_free_lists[index];
3099 vector_free_lists[index] = next_vector (vector);
3100 total_free_vector_slots -= nbytes / word_size;
3102 /* Excess bytes are used for the smaller vector,
3103 which should be set on an appropriate free list. */
3104 restbytes = index * roundup_size + VBLOCK_BYTES_MIN - nbytes;
3105 eassert (restbytes % roundup_size == 0);
3106 SETUP_ON_FREE_LIST (ADVANCE (vector, nbytes), restbytes, index);
3107 return vector;
3110 /* Finally, need a new vector block. */
3111 block = allocate_vector_block ();
3113 /* New vector will be at the beginning of this block. */
3114 vector = (struct Lisp_Vector *) block->data;
3116 /* If the rest of space from this block is large enough
3117 for one-slot vector at least, set up it on a free list. */
3118 restbytes = VECTOR_BLOCK_BYTES - nbytes;
3119 if (restbytes >= VBLOCK_BYTES_MIN)
3121 eassert (restbytes % roundup_size == 0);
3122 SETUP_ON_FREE_LIST (ADVANCE (vector, nbytes), restbytes, index);
3124 return vector;
3127 /* Nonzero if VECTOR pointer is valid pointer inside BLOCK. */
3129 #define VECTOR_IN_BLOCK(vector, block) \
3130 ((char *) (vector) <= (block)->data \
3131 + VECTOR_BLOCK_BYTES - VBLOCK_BYTES_MIN)
3133 /* Return the memory footprint of V in bytes. */
3135 static ptrdiff_t
3136 vector_nbytes (struct Lisp_Vector *v)
3138 ptrdiff_t size = v->header.size & ~ARRAY_MARK_FLAG;
3139 ptrdiff_t nwords;
3141 if (size & PSEUDOVECTOR_FLAG)
3143 if (PSEUDOVECTOR_TYPEP (&v->header, PVEC_BOOL_VECTOR))
3145 struct Lisp_Bool_Vector *bv = (struct Lisp_Bool_Vector *) v;
3146 ptrdiff_t word_bytes = (bool_vector_words (bv->size)
3147 * sizeof (bits_word));
3148 ptrdiff_t boolvec_bytes = bool_header_size + word_bytes;
3149 verify (header_size <= bool_header_size);
3150 nwords = (boolvec_bytes - header_size + word_size - 1) / word_size;
3152 else
3153 nwords = ((size & PSEUDOVECTOR_SIZE_MASK)
3154 + ((size & PSEUDOVECTOR_REST_MASK)
3155 >> PSEUDOVECTOR_SIZE_BITS));
3157 else
3158 nwords = size;
3159 return vroundup (header_size + word_size * nwords);
3162 /* Release extra resources still in use by VECTOR, which may be any
3163 vector-like object. For now, this is used just to free data in
3164 font objects. */
3166 static void
3167 cleanup_vector (struct Lisp_Vector *vector)
3169 detect_suspicious_free (vector);
3170 if (PSEUDOVECTOR_TYPEP (&vector->header, PVEC_FONT)
3171 && ((vector->header.size & PSEUDOVECTOR_SIZE_MASK)
3172 == FONT_OBJECT_MAX))
3174 struct font_driver *drv = ((struct font *) vector)->driver;
3176 /* The font driver might sometimes be NULL, e.g. if Emacs was
3177 interrupted before it had time to set it up. */
3178 if (drv)
3180 /* Attempt to catch subtle bugs like Bug#16140. */
3181 eassert (valid_font_driver (drv));
3182 drv->close ((struct font *) vector);
3187 /* Reclaim space used by unmarked vectors. */
3189 NO_INLINE /* For better stack traces */
3190 static void
3191 sweep_vectors (void)
3193 struct vector_block *block, **bprev = &vector_blocks;
3194 struct large_vector *lv, **lvprev = &large_vectors;
3195 struct Lisp_Vector *vector, *next;
3197 total_vectors = total_vector_slots = total_free_vector_slots = 0;
3198 memset (vector_free_lists, 0, sizeof (vector_free_lists));
3200 /* Looking through vector blocks. */
3202 for (block = vector_blocks; block; block = *bprev)
3204 bool free_this_block = 0;
3205 ptrdiff_t nbytes;
3207 for (vector = (struct Lisp_Vector *) block->data;
3208 VECTOR_IN_BLOCK (vector, block); vector = next)
3210 if (VECTOR_MARKED_P (vector))
3212 VECTOR_UNMARK (vector);
3213 total_vectors++;
3214 nbytes = vector_nbytes (vector);
3215 total_vector_slots += nbytes / word_size;
3216 next = ADVANCE (vector, nbytes);
3218 else
3220 ptrdiff_t total_bytes;
3222 cleanup_vector (vector);
3223 nbytes = vector_nbytes (vector);
3224 total_bytes = nbytes;
3225 next = ADVANCE (vector, nbytes);
3227 /* While NEXT is not marked, try to coalesce with VECTOR,
3228 thus making VECTOR of the largest possible size. */
3230 while (VECTOR_IN_BLOCK (next, block))
3232 if (VECTOR_MARKED_P (next))
3233 break;
3234 cleanup_vector (next);
3235 nbytes = vector_nbytes (next);
3236 total_bytes += nbytes;
3237 next = ADVANCE (next, nbytes);
3240 eassert (total_bytes % roundup_size == 0);
3242 if (vector == (struct Lisp_Vector *) block->data
3243 && !VECTOR_IN_BLOCK (next, block))
3244 /* This block should be freed because all of its
3245 space was coalesced into the only free vector. */
3246 free_this_block = 1;
3247 else
3249 size_t tmp;
3250 SETUP_ON_FREE_LIST (vector, total_bytes, tmp);
3255 if (free_this_block)
3257 *bprev = block->next;
3258 #ifndef GC_MALLOC_CHECK
3259 mem_delete (mem_find (block->data));
3260 #endif
3261 xfree (block);
3263 else
3264 bprev = &block->next;
3267 /* Sweep large vectors. */
3269 for (lv = large_vectors; lv; lv = *lvprev)
3271 vector = large_vector_vec (lv);
3272 if (VECTOR_MARKED_P (vector))
3274 VECTOR_UNMARK (vector);
3275 total_vectors++;
3276 if (vector->header.size & PSEUDOVECTOR_FLAG)
3278 /* All non-bool pseudovectors are small enough to be allocated
3279 from vector blocks. This code should be redesigned if some
3280 pseudovector type grows beyond VBLOCK_BYTES_MAX. */
3281 eassert (PSEUDOVECTOR_TYPEP (&vector->header, PVEC_BOOL_VECTOR));
3282 total_vector_slots += vector_nbytes (vector) / word_size;
3284 else
3285 total_vector_slots
3286 += header_size / word_size + vector->header.size;
3287 lvprev = &lv->next;
3289 else
3291 *lvprev = lv->next;
3292 lisp_free (lv);
3297 /* Value is a pointer to a newly allocated Lisp_Vector structure
3298 with room for LEN Lisp_Objects. */
3300 static struct Lisp_Vector *
3301 allocate_vectorlike (ptrdiff_t len)
3303 struct Lisp_Vector *p;
3305 MALLOC_BLOCK_INPUT;
3307 if (len == 0)
3308 p = XVECTOR (zero_vector);
3309 else
3311 size_t nbytes = header_size + len * word_size;
3313 #ifdef DOUG_LEA_MALLOC
3314 if (!mmap_lisp_allowed_p ())
3315 mallopt (M_MMAP_MAX, 0);
3316 #endif
3318 if (nbytes <= VBLOCK_BYTES_MAX)
3319 p = allocate_vector_from_block (vroundup (nbytes));
3320 else
3322 struct large_vector *lv
3323 = lisp_malloc ((large_vector_offset + header_size
3324 + len * word_size),
3325 MEM_TYPE_VECTORLIKE);
3326 lv->next = large_vectors;
3327 large_vectors = lv;
3328 p = large_vector_vec (lv);
3331 #ifdef DOUG_LEA_MALLOC
3332 if (!mmap_lisp_allowed_p ())
3333 mallopt (M_MMAP_MAX, MMAP_MAX_AREAS);
3334 #endif
3336 if (find_suspicious_object_in_range (p, (char *) p + nbytes))
3337 emacs_abort ();
3339 consing_since_gc += nbytes;
3340 vector_cells_consed += len;
3343 MALLOC_UNBLOCK_INPUT;
3345 return p;
3349 /* Allocate a vector with LEN slots. */
3351 struct Lisp_Vector *
3352 allocate_vector (EMACS_INT len)
3354 struct Lisp_Vector *v;
3355 ptrdiff_t nbytes_max = min (PTRDIFF_MAX, SIZE_MAX);
3357 if (min ((nbytes_max - header_size) / word_size, MOST_POSITIVE_FIXNUM) < len)
3358 memory_full (SIZE_MAX);
3359 v = allocate_vectorlike (len);
3360 if (len)
3361 v->header.size = len;
3362 return v;
3366 /* Allocate other vector-like structures. */
3368 struct Lisp_Vector *
3369 allocate_pseudovector (int memlen, int lisplen,
3370 int zerolen, enum pvec_type tag)
3372 struct Lisp_Vector *v = allocate_vectorlike (memlen);
3374 /* Catch bogus values. */
3375 eassert (0 <= tag && tag <= PVEC_FONT);
3376 eassert (0 <= lisplen && lisplen <= zerolen && zerolen <= memlen);
3377 eassert (memlen - lisplen <= (1 << PSEUDOVECTOR_REST_BITS) - 1);
3378 eassert (lisplen <= (1 << PSEUDOVECTOR_SIZE_BITS) - 1);
3380 /* Only the first LISPLEN slots will be traced normally by the GC. */
3381 memclear (v->contents, zerolen * word_size);
3382 XSETPVECTYPESIZE (v, tag, lisplen, memlen - lisplen);
3383 return v;
3386 struct buffer *
3387 allocate_buffer (void)
3389 struct buffer *b = lisp_malloc (sizeof *b, MEM_TYPE_BUFFER);
3391 BUFFER_PVEC_INIT (b);
3392 /* Put B on the chain of all buffers including killed ones. */
3393 b->next = all_buffers;
3394 all_buffers = b;
3395 /* Note that the rest fields of B are not initialized. */
3396 return b;
3399 DEFUN ("make-vector", Fmake_vector, Smake_vector, 2, 2, 0,
3400 doc: /* Return a newly created vector of length LENGTH, with each element being INIT.
3401 See also the function `vector'. */)
3402 (Lisp_Object length, Lisp_Object init)
3404 CHECK_NATNUM (length);
3405 struct Lisp_Vector *p = allocate_vector (XFASTINT (length));
3406 for (ptrdiff_t i = 0; i < XFASTINT (length); i++)
3407 p->contents[i] = init;
3408 return make_lisp_ptr (p, Lisp_Vectorlike);
3411 DEFUN ("vector", Fvector, Svector, 0, MANY, 0,
3412 doc: /* Return a newly created vector with specified arguments as elements.
3413 Any number of arguments, even zero arguments, are allowed.
3414 usage: (vector &rest OBJECTS) */)
3415 (ptrdiff_t nargs, Lisp_Object *args)
3417 Lisp_Object val = make_uninit_vector (nargs);
3418 struct Lisp_Vector *p = XVECTOR (val);
3419 memcpy (p->contents, args, nargs * sizeof *args);
3420 return val;
3423 void
3424 make_byte_code (struct Lisp_Vector *v)
3426 /* Don't allow the global zero_vector to become a byte code object. */
3427 eassert (0 < v->header.size);
3429 if (v->header.size > 1 && STRINGP (v->contents[1])
3430 && STRING_MULTIBYTE (v->contents[1]))
3431 /* BYTECODE-STRING must have been produced by Emacs 20.2 or the
3432 earlier because they produced a raw 8-bit string for byte-code
3433 and now such a byte-code string is loaded as multibyte while
3434 raw 8-bit characters converted to multibyte form. Thus, now we
3435 must convert them back to the original unibyte form. */
3436 v->contents[1] = Fstring_as_unibyte (v->contents[1]);
3437 XSETPVECTYPE (v, PVEC_COMPILED);
3440 DEFUN ("make-byte-code", Fmake_byte_code, Smake_byte_code, 4, MANY, 0,
3441 doc: /* Create a byte-code object with specified arguments as elements.
3442 The arguments should be the ARGLIST, bytecode-string BYTE-CODE, constant
3443 vector CONSTANTS, maximum stack size DEPTH, (optional) DOCSTRING,
3444 and (optional) INTERACTIVE-SPEC.
3445 The first four arguments are required; at most six have any
3446 significance.
3447 The ARGLIST can be either like the one of `lambda', in which case the arguments
3448 will be dynamically bound before executing the byte code, or it can be an
3449 integer of the form NNNNNNNRMMMMMMM where the 7bit MMMMMMM specifies the
3450 minimum number of arguments, the 7-bit NNNNNNN specifies the maximum number
3451 of arguments (ignoring &rest) and the R bit specifies whether there is a &rest
3452 argument to catch the left-over arguments. If such an integer is used, the
3453 arguments will not be dynamically bound but will be instead pushed on the
3454 stack before executing the byte-code.
3455 usage: (make-byte-code ARGLIST BYTE-CODE CONSTANTS DEPTH &optional DOCSTRING INTERACTIVE-SPEC &rest ELEMENTS) */)
3456 (ptrdiff_t nargs, Lisp_Object *args)
3458 Lisp_Object val = make_uninit_vector (nargs);
3459 struct Lisp_Vector *p = XVECTOR (val);
3461 /* We used to purecopy everything here, if purify-flag was set. This worked
3462 OK for Emacs-23, but with Emacs-24's lexical binding code, it can be
3463 dangerous, since make-byte-code is used during execution to build
3464 closures, so any closure built during the preload phase would end up
3465 copied into pure space, including its free variables, which is sometimes
3466 just wasteful and other times plainly wrong (e.g. those free vars may want
3467 to be setcar'd). */
3469 memcpy (p->contents, args, nargs * sizeof *args);
3470 make_byte_code (p);
3471 XSETCOMPILED (val, p);
3472 return val;
3477 /***********************************************************************
3478 Symbol Allocation
3479 ***********************************************************************/
3481 /* Like struct Lisp_Symbol, but padded so that the size is a multiple
3482 of the required alignment. */
3484 union aligned_Lisp_Symbol
3486 struct Lisp_Symbol s;
3487 unsigned char c[(sizeof (struct Lisp_Symbol) + GCALIGNMENT - 1)
3488 & -GCALIGNMENT];
3491 /* Each symbol_block is just under 1020 bytes long, since malloc
3492 really allocates in units of powers of two and uses 4 bytes for its
3493 own overhead. */
3495 #define SYMBOL_BLOCK_SIZE \
3496 ((1020 - sizeof (struct symbol_block *)) / sizeof (union aligned_Lisp_Symbol))
3498 struct symbol_block
3500 /* Place `symbols' first, to preserve alignment. */
3501 union aligned_Lisp_Symbol symbols[SYMBOL_BLOCK_SIZE];
3502 struct symbol_block *next;
3505 /* Current symbol block and index of first unused Lisp_Symbol
3506 structure in it. */
3508 static struct symbol_block *symbol_block;
3509 static int symbol_block_index = SYMBOL_BLOCK_SIZE;
3510 /* Pointer to the first symbol_block that contains pinned symbols.
3511 Tests for 24.4 showed that at dump-time, Emacs contains about 15K symbols,
3512 10K of which are pinned (and all but 250 of them are interned in obarray),
3513 whereas a "typical session" has in the order of 30K symbols.
3514 `symbol_block_pinned' lets mark_pinned_symbols scan only 15K symbols rather
3515 than 30K to find the 10K symbols we need to mark. */
3516 static struct symbol_block *symbol_block_pinned;
3518 /* List of free symbols. */
3520 static struct Lisp_Symbol *symbol_free_list;
3522 static void
3523 set_symbol_name (Lisp_Object sym, Lisp_Object name)
3525 XSYMBOL (sym)->name = name;
3528 void
3529 init_symbol (Lisp_Object val, Lisp_Object name)
3531 struct Lisp_Symbol *p = XSYMBOL (val);
3532 set_symbol_name (val, name);
3533 set_symbol_plist (val, Qnil);
3534 p->redirect = SYMBOL_PLAINVAL;
3535 SET_SYMBOL_VAL (p, Qunbound);
3536 set_symbol_function (val, Qnil);
3537 set_symbol_next (val, NULL);
3538 p->gcmarkbit = false;
3539 p->interned = SYMBOL_UNINTERNED;
3540 p->constant = 0;
3541 p->declared_special = false;
3542 p->pinned = false;
3545 DEFUN ("make-symbol", Fmake_symbol, Smake_symbol, 1, 1, 0,
3546 doc: /* Return a newly allocated uninterned symbol whose name is NAME.
3547 Its value is void, and its function definition and property list are nil. */)
3548 (Lisp_Object name)
3550 Lisp_Object val;
3552 CHECK_STRING (name);
3554 MALLOC_BLOCK_INPUT;
3556 if (symbol_free_list)
3558 XSETSYMBOL (val, symbol_free_list);
3559 symbol_free_list = symbol_free_list->next;
3561 else
3563 if (symbol_block_index == SYMBOL_BLOCK_SIZE)
3565 struct symbol_block *new
3566 = lisp_malloc (sizeof *new, MEM_TYPE_SYMBOL);
3567 new->next = symbol_block;
3568 symbol_block = new;
3569 symbol_block_index = 0;
3570 total_free_symbols += SYMBOL_BLOCK_SIZE;
3572 XSETSYMBOL (val, &symbol_block->symbols[symbol_block_index].s);
3573 symbol_block_index++;
3576 MALLOC_UNBLOCK_INPUT;
3578 init_symbol (val, name);
3579 consing_since_gc += sizeof (struct Lisp_Symbol);
3580 symbols_consed++;
3581 total_free_symbols--;
3582 return val;
3587 /***********************************************************************
3588 Marker (Misc) Allocation
3589 ***********************************************************************/
3591 /* Like union Lisp_Misc, but padded so that its size is a multiple of
3592 the required alignment. */
3594 union aligned_Lisp_Misc
3596 union Lisp_Misc m;
3597 unsigned char c[(sizeof (union Lisp_Misc) + GCALIGNMENT - 1)
3598 & -GCALIGNMENT];
3601 /* Allocation of markers and other objects that share that structure.
3602 Works like allocation of conses. */
3604 #define MARKER_BLOCK_SIZE \
3605 ((1020 - sizeof (struct marker_block *)) / sizeof (union aligned_Lisp_Misc))
3607 struct marker_block
3609 /* Place `markers' first, to preserve alignment. */
3610 union aligned_Lisp_Misc markers[MARKER_BLOCK_SIZE];
3611 struct marker_block *next;
3614 static struct marker_block *marker_block;
3615 static int marker_block_index = MARKER_BLOCK_SIZE;
3617 static union Lisp_Misc *marker_free_list;
3619 /* Return a newly allocated Lisp_Misc object of specified TYPE. */
3621 static Lisp_Object
3622 allocate_misc (enum Lisp_Misc_Type type)
3624 Lisp_Object val;
3626 MALLOC_BLOCK_INPUT;
3628 if (marker_free_list)
3630 XSETMISC (val, marker_free_list);
3631 marker_free_list = marker_free_list->u_free.chain;
3633 else
3635 if (marker_block_index == MARKER_BLOCK_SIZE)
3637 struct marker_block *new = lisp_malloc (sizeof *new, MEM_TYPE_MISC);
3638 new->next = marker_block;
3639 marker_block = new;
3640 marker_block_index = 0;
3641 total_free_markers += MARKER_BLOCK_SIZE;
3643 XSETMISC (val, &marker_block->markers[marker_block_index].m);
3644 marker_block_index++;
3647 MALLOC_UNBLOCK_INPUT;
3649 --total_free_markers;
3650 consing_since_gc += sizeof (union Lisp_Misc);
3651 misc_objects_consed++;
3652 XMISCANY (val)->type = type;
3653 XMISCANY (val)->gcmarkbit = 0;
3654 return val;
3657 /* Free a Lisp_Misc object. */
3659 void
3660 free_misc (Lisp_Object misc)
3662 XMISCANY (misc)->type = Lisp_Misc_Free;
3663 XMISC (misc)->u_free.chain = marker_free_list;
3664 marker_free_list = XMISC (misc);
3665 consing_since_gc -= sizeof (union Lisp_Misc);
3666 total_free_markers++;
3669 /* Verify properties of Lisp_Save_Value's representation
3670 that are assumed here and elsewhere. */
3672 verify (SAVE_UNUSED == 0);
3673 verify (((SAVE_INTEGER | SAVE_POINTER | SAVE_FUNCPOINTER | SAVE_OBJECT)
3674 >> SAVE_SLOT_BITS)
3675 == 0);
3677 /* Return Lisp_Save_Value objects for the various combinations
3678 that callers need. */
3680 Lisp_Object
3681 make_save_int_int_int (ptrdiff_t a, ptrdiff_t b, ptrdiff_t c)
3683 Lisp_Object val = allocate_misc (Lisp_Misc_Save_Value);
3684 struct Lisp_Save_Value *p = XSAVE_VALUE (val);
3685 p->save_type = SAVE_TYPE_INT_INT_INT;
3686 p->data[0].integer = a;
3687 p->data[1].integer = b;
3688 p->data[2].integer = c;
3689 return val;
3692 Lisp_Object
3693 make_save_obj_obj_obj_obj (Lisp_Object a, Lisp_Object b, Lisp_Object c,
3694 Lisp_Object d)
3696 Lisp_Object val = allocate_misc (Lisp_Misc_Save_Value);
3697 struct Lisp_Save_Value *p = XSAVE_VALUE (val);
3698 p->save_type = SAVE_TYPE_OBJ_OBJ_OBJ_OBJ;
3699 p->data[0].object = a;
3700 p->data[1].object = b;
3701 p->data[2].object = c;
3702 p->data[3].object = d;
3703 return val;
3706 Lisp_Object
3707 make_save_ptr (void *a)
3709 Lisp_Object val = allocate_misc (Lisp_Misc_Save_Value);
3710 struct Lisp_Save_Value *p = XSAVE_VALUE (val);
3711 p->save_type = SAVE_POINTER;
3712 p->data[0].pointer = a;
3713 return val;
3716 Lisp_Object
3717 make_save_ptr_int (void *a, ptrdiff_t b)
3719 Lisp_Object val = allocate_misc (Lisp_Misc_Save_Value);
3720 struct Lisp_Save_Value *p = XSAVE_VALUE (val);
3721 p->save_type = SAVE_TYPE_PTR_INT;
3722 p->data[0].pointer = a;
3723 p->data[1].integer = b;
3724 return val;
3727 Lisp_Object
3728 make_save_ptr_ptr (void *a, void *b)
3730 Lisp_Object val = allocate_misc (Lisp_Misc_Save_Value);
3731 struct Lisp_Save_Value *p = XSAVE_VALUE (val);
3732 p->save_type = SAVE_TYPE_PTR_PTR;
3733 p->data[0].pointer = a;
3734 p->data[1].pointer = b;
3735 return val;
3738 Lisp_Object
3739 make_save_funcptr_ptr_obj (void (*a) (void), void *b, Lisp_Object c)
3741 Lisp_Object val = allocate_misc (Lisp_Misc_Save_Value);
3742 struct Lisp_Save_Value *p = XSAVE_VALUE (val);
3743 p->save_type = SAVE_TYPE_FUNCPTR_PTR_OBJ;
3744 p->data[0].funcpointer = a;
3745 p->data[1].pointer = b;
3746 p->data[2].object = c;
3747 return val;
3750 /* Return a Lisp_Save_Value object that represents an array A
3751 of N Lisp objects. */
3753 Lisp_Object
3754 make_save_memory (Lisp_Object *a, ptrdiff_t n)
3756 Lisp_Object val = allocate_misc (Lisp_Misc_Save_Value);
3757 struct Lisp_Save_Value *p = XSAVE_VALUE (val);
3758 p->save_type = SAVE_TYPE_MEMORY;
3759 p->data[0].pointer = a;
3760 p->data[1].integer = n;
3761 return val;
3764 /* Free a Lisp_Save_Value object. Do not use this function
3765 if SAVE contains pointer other than returned by xmalloc. */
3767 void
3768 free_save_value (Lisp_Object save)
3770 xfree (XSAVE_POINTER (save, 0));
3771 free_misc (save);
3774 /* Return a Lisp_Misc_Overlay object with specified START, END and PLIST. */
3776 Lisp_Object
3777 build_overlay (Lisp_Object start, Lisp_Object end, Lisp_Object plist)
3779 register Lisp_Object overlay;
3781 overlay = allocate_misc (Lisp_Misc_Overlay);
3782 OVERLAY_START (overlay) = start;
3783 OVERLAY_END (overlay) = end;
3784 set_overlay_plist (overlay, plist);
3785 XOVERLAY (overlay)->next = NULL;
3786 return overlay;
3789 DEFUN ("make-marker", Fmake_marker, Smake_marker, 0, 0, 0,
3790 doc: /* Return a newly allocated marker which does not point at any place. */)
3791 (void)
3793 register Lisp_Object val;
3794 register struct Lisp_Marker *p;
3796 val = allocate_misc (Lisp_Misc_Marker);
3797 p = XMARKER (val);
3798 p->buffer = 0;
3799 p->bytepos = 0;
3800 p->charpos = 0;
3801 p->next = NULL;
3802 p->insertion_type = 0;
3803 p->need_adjustment = 0;
3804 return val;
3807 /* Return a newly allocated marker which points into BUF
3808 at character position CHARPOS and byte position BYTEPOS. */
3810 Lisp_Object
3811 build_marker (struct buffer *buf, ptrdiff_t charpos, ptrdiff_t bytepos)
3813 Lisp_Object obj;
3814 struct Lisp_Marker *m;
3816 /* No dead buffers here. */
3817 eassert (BUFFER_LIVE_P (buf));
3819 /* Every character is at least one byte. */
3820 eassert (charpos <= bytepos);
3822 obj = allocate_misc (Lisp_Misc_Marker);
3823 m = XMARKER (obj);
3824 m->buffer = buf;
3825 m->charpos = charpos;
3826 m->bytepos = bytepos;
3827 m->insertion_type = 0;
3828 m->need_adjustment = 0;
3829 m->next = BUF_MARKERS (buf);
3830 BUF_MARKERS (buf) = m;
3831 return obj;
3834 /* Put MARKER back on the free list after using it temporarily. */
3836 void
3837 free_marker (Lisp_Object marker)
3839 unchain_marker (XMARKER (marker));
3840 free_misc (marker);
3844 /* Return a newly created vector or string with specified arguments as
3845 elements. If all the arguments are characters that can fit
3846 in a string of events, make a string; otherwise, make a vector.
3848 Any number of arguments, even zero arguments, are allowed. */
3850 Lisp_Object
3851 make_event_array (ptrdiff_t nargs, Lisp_Object *args)
3853 ptrdiff_t i;
3855 for (i = 0; i < nargs; i++)
3856 /* The things that fit in a string
3857 are characters that are in 0...127,
3858 after discarding the meta bit and all the bits above it. */
3859 if (!INTEGERP (args[i])
3860 || (XINT (args[i]) & ~(-CHAR_META)) >= 0200)
3861 return Fvector (nargs, args);
3863 /* Since the loop exited, we know that all the things in it are
3864 characters, so we can make a string. */
3866 Lisp_Object result;
3868 result = Fmake_string (make_number (nargs), make_number (0));
3869 for (i = 0; i < nargs; i++)
3871 SSET (result, i, XINT (args[i]));
3872 /* Move the meta bit to the right place for a string char. */
3873 if (XINT (args[i]) & CHAR_META)
3874 SSET (result, i, SREF (result, i) | 0x80);
3877 return result;
3881 #ifdef HAVE_MODULES
3882 /* Create a new module user ptr object. */
3883 Lisp_Object
3884 make_user_ptr (void (*finalizer) (void *), void *p)
3886 Lisp_Object obj;
3887 struct Lisp_User_Ptr *uptr;
3889 obj = allocate_misc (Lisp_Misc_User_Ptr);
3890 uptr = XUSER_PTR (obj);
3891 uptr->finalizer = finalizer;
3892 uptr->p = p;
3893 return obj;
3896 #endif
3898 static void
3899 init_finalizer_list (struct Lisp_Finalizer *head)
3901 head->prev = head->next = head;
3904 /* Insert FINALIZER before ELEMENT. */
3906 static void
3907 finalizer_insert (struct Lisp_Finalizer *element,
3908 struct Lisp_Finalizer *finalizer)
3910 eassert (finalizer->prev == NULL);
3911 eassert (finalizer->next == NULL);
3912 finalizer->next = element;
3913 finalizer->prev = element->prev;
3914 finalizer->prev->next = finalizer;
3915 element->prev = finalizer;
3918 static void
3919 unchain_finalizer (struct Lisp_Finalizer *finalizer)
3921 if (finalizer->prev != NULL)
3923 eassert (finalizer->next != NULL);
3924 finalizer->prev->next = finalizer->next;
3925 finalizer->next->prev = finalizer->prev;
3926 finalizer->prev = finalizer->next = NULL;
3930 static void
3931 mark_finalizer_list (struct Lisp_Finalizer *head)
3933 for (struct Lisp_Finalizer *finalizer = head->next;
3934 finalizer != head;
3935 finalizer = finalizer->next)
3937 finalizer->base.gcmarkbit = true;
3938 mark_object (finalizer->function);
3942 /* Move doomed finalizers to list DEST from list SRC. A doomed
3943 finalizer is one that is not GC-reachable and whose
3944 finalizer->function is non-nil. */
3946 static void
3947 queue_doomed_finalizers (struct Lisp_Finalizer *dest,
3948 struct Lisp_Finalizer *src)
3950 struct Lisp_Finalizer *finalizer = src->next;
3951 while (finalizer != src)
3953 struct Lisp_Finalizer *next = finalizer->next;
3954 if (!finalizer->base.gcmarkbit && !NILP (finalizer->function))
3956 unchain_finalizer (finalizer);
3957 finalizer_insert (dest, finalizer);
3960 finalizer = next;
3964 static Lisp_Object
3965 run_finalizer_handler (Lisp_Object args)
3967 add_to_log ("finalizer failed: %S", args);
3968 return Qnil;
3971 static void
3972 run_finalizer_function (Lisp_Object function)
3974 ptrdiff_t count = SPECPDL_INDEX ();
3976 specbind (Qinhibit_quit, Qt);
3977 internal_condition_case_1 (call0, function, Qt, run_finalizer_handler);
3978 unbind_to (count, Qnil);
3981 static void
3982 run_finalizers (struct Lisp_Finalizer *finalizers)
3984 struct Lisp_Finalizer *finalizer;
3985 Lisp_Object function;
3987 while (finalizers->next != finalizers)
3989 finalizer = finalizers->next;
3990 eassert (finalizer->base.type == Lisp_Misc_Finalizer);
3991 unchain_finalizer (finalizer);
3992 function = finalizer->function;
3993 if (!NILP (function))
3995 finalizer->function = Qnil;
3996 run_finalizer_function (function);
4001 DEFUN ("make-finalizer", Fmake_finalizer, Smake_finalizer, 1, 1, 0,
4002 doc: /* Make a finalizer that will run FUNCTION.
4003 FUNCTION will be called after garbage collection when the returned
4004 finalizer object becomes unreachable. If the finalizer object is
4005 reachable only through references from finalizer objects, it does not
4006 count as reachable for the purpose of deciding whether to run
4007 FUNCTION. FUNCTION will be run once per finalizer object. */)
4008 (Lisp_Object function)
4010 Lisp_Object val = allocate_misc (Lisp_Misc_Finalizer);
4011 struct Lisp_Finalizer *finalizer = XFINALIZER (val);
4012 finalizer->function = function;
4013 finalizer->prev = finalizer->next = NULL;
4014 finalizer_insert (&finalizers, finalizer);
4015 return val;
4019 /************************************************************************
4020 Memory Full Handling
4021 ************************************************************************/
4024 /* Called if malloc (NBYTES) returns zero. If NBYTES == SIZE_MAX,
4025 there may have been size_t overflow so that malloc was never
4026 called, or perhaps malloc was invoked successfully but the
4027 resulting pointer had problems fitting into a tagged EMACS_INT. In
4028 either case this counts as memory being full even though malloc did
4029 not fail. */
4031 void
4032 memory_full (size_t nbytes)
4034 /* Do not go into hysterics merely because a large request failed. */
4035 bool enough_free_memory = 0;
4036 if (SPARE_MEMORY < nbytes)
4038 void *p;
4040 MALLOC_BLOCK_INPUT;
4041 p = malloc (SPARE_MEMORY);
4042 if (p)
4044 free (p);
4045 enough_free_memory = 1;
4047 MALLOC_UNBLOCK_INPUT;
4050 if (! enough_free_memory)
4052 int i;
4054 Vmemory_full = Qt;
4056 memory_full_cons_threshold = sizeof (struct cons_block);
4058 /* The first time we get here, free the spare memory. */
4059 for (i = 0; i < ARRAYELTS (spare_memory); i++)
4060 if (spare_memory[i])
4062 if (i == 0)
4063 free (spare_memory[i]);
4064 else if (i >= 1 && i <= 4)
4065 lisp_align_free (spare_memory[i]);
4066 else
4067 lisp_free (spare_memory[i]);
4068 spare_memory[i] = 0;
4072 /* This used to call error, but if we've run out of memory, we could
4073 get infinite recursion trying to build the string. */
4074 xsignal (Qnil, Vmemory_signal_data);
4077 /* If we released our reserve (due to running out of memory),
4078 and we have a fair amount free once again,
4079 try to set aside another reserve in case we run out once more.
4081 This is called when a relocatable block is freed in ralloc.c,
4082 and also directly from this file, in case we're not using ralloc.c. */
4084 void
4085 refill_memory_reserve (void)
4087 #if !defined SYSTEM_MALLOC && !defined HYBRID_MALLOC
4088 if (spare_memory[0] == 0)
4089 spare_memory[0] = malloc (SPARE_MEMORY);
4090 if (spare_memory[1] == 0)
4091 spare_memory[1] = lisp_align_malloc (sizeof (struct cons_block),
4092 MEM_TYPE_SPARE);
4093 if (spare_memory[2] == 0)
4094 spare_memory[2] = lisp_align_malloc (sizeof (struct cons_block),
4095 MEM_TYPE_SPARE);
4096 if (spare_memory[3] == 0)
4097 spare_memory[3] = lisp_align_malloc (sizeof (struct cons_block),
4098 MEM_TYPE_SPARE);
4099 if (spare_memory[4] == 0)
4100 spare_memory[4] = lisp_align_malloc (sizeof (struct cons_block),
4101 MEM_TYPE_SPARE);
4102 if (spare_memory[5] == 0)
4103 spare_memory[5] = lisp_malloc (sizeof (struct string_block),
4104 MEM_TYPE_SPARE);
4105 if (spare_memory[6] == 0)
4106 spare_memory[6] = lisp_malloc (sizeof (struct string_block),
4107 MEM_TYPE_SPARE);
4108 if (spare_memory[0] && spare_memory[1] && spare_memory[5])
4109 Vmemory_full = Qnil;
4110 #endif
4113 /************************************************************************
4114 C Stack Marking
4115 ************************************************************************/
4117 /* Conservative C stack marking requires a method to identify possibly
4118 live Lisp objects given a pointer value. We do this by keeping
4119 track of blocks of Lisp data that are allocated in a red-black tree
4120 (see also the comment of mem_node which is the type of nodes in
4121 that tree). Function lisp_malloc adds information for an allocated
4122 block to the red-black tree with calls to mem_insert, and function
4123 lisp_free removes it with mem_delete. Functions live_string_p etc
4124 call mem_find to lookup information about a given pointer in the
4125 tree, and use that to determine if the pointer points to a Lisp
4126 object or not. */
4128 /* Initialize this part of alloc.c. */
4130 static void
4131 mem_init (void)
4133 mem_z.left = mem_z.right = MEM_NIL;
4134 mem_z.parent = NULL;
4135 mem_z.color = MEM_BLACK;
4136 mem_z.start = mem_z.end = NULL;
4137 mem_root = MEM_NIL;
4141 /* Value is a pointer to the mem_node containing START. Value is
4142 MEM_NIL if there is no node in the tree containing START. */
4144 static struct mem_node *
4145 mem_find (void *start)
4147 struct mem_node *p;
4149 if (start < min_heap_address || start > max_heap_address)
4150 return MEM_NIL;
4152 /* Make the search always successful to speed up the loop below. */
4153 mem_z.start = start;
4154 mem_z.end = (char *) start + 1;
4156 p = mem_root;
4157 while (start < p->start || start >= p->end)
4158 p = start < p->start ? p->left : p->right;
4159 return p;
4163 /* Insert a new node into the tree for a block of memory with start
4164 address START, end address END, and type TYPE. Value is a
4165 pointer to the node that was inserted. */
4167 static struct mem_node *
4168 mem_insert (void *start, void *end, enum mem_type type)
4170 struct mem_node *c, *parent, *x;
4172 if (min_heap_address == NULL || start < min_heap_address)
4173 min_heap_address = start;
4174 if (max_heap_address == NULL || end > max_heap_address)
4175 max_heap_address = end;
4177 /* See where in the tree a node for START belongs. In this
4178 particular application, it shouldn't happen that a node is already
4179 present. For debugging purposes, let's check that. */
4180 c = mem_root;
4181 parent = NULL;
4183 while (c != MEM_NIL)
4185 parent = c;
4186 c = start < c->start ? c->left : c->right;
4189 /* Create a new node. */
4190 #ifdef GC_MALLOC_CHECK
4191 x = malloc (sizeof *x);
4192 if (x == NULL)
4193 emacs_abort ();
4194 #else
4195 x = xmalloc (sizeof *x);
4196 #endif
4197 x->start = start;
4198 x->end = end;
4199 x->type = type;
4200 x->parent = parent;
4201 x->left = x->right = MEM_NIL;
4202 x->color = MEM_RED;
4204 /* Insert it as child of PARENT or install it as root. */
4205 if (parent)
4207 if (start < parent->start)
4208 parent->left = x;
4209 else
4210 parent->right = x;
4212 else
4213 mem_root = x;
4215 /* Re-establish red-black tree properties. */
4216 mem_insert_fixup (x);
4218 return x;
4222 /* Re-establish the red-black properties of the tree, and thereby
4223 balance the tree, after node X has been inserted; X is always red. */
4225 static void
4226 mem_insert_fixup (struct mem_node *x)
4228 while (x != mem_root && x->parent->color == MEM_RED)
4230 /* X is red and its parent is red. This is a violation of
4231 red-black tree property #3. */
4233 if (x->parent == x->parent->parent->left)
4235 /* We're on the left side of our grandparent, and Y is our
4236 "uncle". */
4237 struct mem_node *y = x->parent->parent->right;
4239 if (y->color == MEM_RED)
4241 /* Uncle and parent are red but should be black because
4242 X is red. Change the colors accordingly and proceed
4243 with the grandparent. */
4244 x->parent->color = MEM_BLACK;
4245 y->color = MEM_BLACK;
4246 x->parent->parent->color = MEM_RED;
4247 x = x->parent->parent;
4249 else
4251 /* Parent and uncle have different colors; parent is
4252 red, uncle is black. */
4253 if (x == x->parent->right)
4255 x = x->parent;
4256 mem_rotate_left (x);
4259 x->parent->color = MEM_BLACK;
4260 x->parent->parent->color = MEM_RED;
4261 mem_rotate_right (x->parent->parent);
4264 else
4266 /* This is the symmetrical case of above. */
4267 struct mem_node *y = x->parent->parent->left;
4269 if (y->color == MEM_RED)
4271 x->parent->color = MEM_BLACK;
4272 y->color = MEM_BLACK;
4273 x->parent->parent->color = MEM_RED;
4274 x = x->parent->parent;
4276 else
4278 if (x == x->parent->left)
4280 x = x->parent;
4281 mem_rotate_right (x);
4284 x->parent->color = MEM_BLACK;
4285 x->parent->parent->color = MEM_RED;
4286 mem_rotate_left (x->parent->parent);
4291 /* The root may have been changed to red due to the algorithm. Set
4292 it to black so that property #5 is satisfied. */
4293 mem_root->color = MEM_BLACK;
4297 /* (x) (y)
4298 / \ / \
4299 a (y) ===> (x) c
4300 / \ / \
4301 b c a b */
4303 static void
4304 mem_rotate_left (struct mem_node *x)
4306 struct mem_node *y;
4308 /* Turn y's left sub-tree into x's right sub-tree. */
4309 y = x->right;
4310 x->right = y->left;
4311 if (y->left != MEM_NIL)
4312 y->left->parent = x;
4314 /* Y's parent was x's parent. */
4315 if (y != MEM_NIL)
4316 y->parent = x->parent;
4318 /* Get the parent to point to y instead of x. */
4319 if (x->parent)
4321 if (x == x->parent->left)
4322 x->parent->left = y;
4323 else
4324 x->parent->right = y;
4326 else
4327 mem_root = y;
4329 /* Put x on y's left. */
4330 y->left = x;
4331 if (x != MEM_NIL)
4332 x->parent = y;
4336 /* (x) (Y)
4337 / \ / \
4338 (y) c ===> a (x)
4339 / \ / \
4340 a b b c */
4342 static void
4343 mem_rotate_right (struct mem_node *x)
4345 struct mem_node *y = x->left;
4347 x->left = y->right;
4348 if (y->right != MEM_NIL)
4349 y->right->parent = x;
4351 if (y != MEM_NIL)
4352 y->parent = x->parent;
4353 if (x->parent)
4355 if (x == x->parent->right)
4356 x->parent->right = y;
4357 else
4358 x->parent->left = y;
4360 else
4361 mem_root = y;
4363 y->right = x;
4364 if (x != MEM_NIL)
4365 x->parent = y;
4369 /* Delete node Z from the tree. If Z is null or MEM_NIL, do nothing. */
4371 static void
4372 mem_delete (struct mem_node *z)
4374 struct mem_node *x, *y;
4376 if (!z || z == MEM_NIL)
4377 return;
4379 if (z->left == MEM_NIL || z->right == MEM_NIL)
4380 y = z;
4381 else
4383 y = z->right;
4384 while (y->left != MEM_NIL)
4385 y = y->left;
4388 if (y->left != MEM_NIL)
4389 x = y->left;
4390 else
4391 x = y->right;
4393 x->parent = y->parent;
4394 if (y->parent)
4396 if (y == y->parent->left)
4397 y->parent->left = x;
4398 else
4399 y->parent->right = x;
4401 else
4402 mem_root = x;
4404 if (y != z)
4406 z->start = y->start;
4407 z->end = y->end;
4408 z->type = y->type;
4411 if (y->color == MEM_BLACK)
4412 mem_delete_fixup (x);
4414 #ifdef GC_MALLOC_CHECK
4415 free (y);
4416 #else
4417 xfree (y);
4418 #endif
4422 /* Re-establish the red-black properties of the tree, after a
4423 deletion. */
4425 static void
4426 mem_delete_fixup (struct mem_node *x)
4428 while (x != mem_root && x->color == MEM_BLACK)
4430 if (x == x->parent->left)
4432 struct mem_node *w = x->parent->right;
4434 if (w->color == MEM_RED)
4436 w->color = MEM_BLACK;
4437 x->parent->color = MEM_RED;
4438 mem_rotate_left (x->parent);
4439 w = x->parent->right;
4442 if (w->left->color == MEM_BLACK && w->right->color == MEM_BLACK)
4444 w->color = MEM_RED;
4445 x = x->parent;
4447 else
4449 if (w->right->color == MEM_BLACK)
4451 w->left->color = MEM_BLACK;
4452 w->color = MEM_RED;
4453 mem_rotate_right (w);
4454 w = x->parent->right;
4456 w->color = x->parent->color;
4457 x->parent->color = MEM_BLACK;
4458 w->right->color = MEM_BLACK;
4459 mem_rotate_left (x->parent);
4460 x = mem_root;
4463 else
4465 struct mem_node *w = x->parent->left;
4467 if (w->color == MEM_RED)
4469 w->color = MEM_BLACK;
4470 x->parent->color = MEM_RED;
4471 mem_rotate_right (x->parent);
4472 w = x->parent->left;
4475 if (w->right->color == MEM_BLACK && w->left->color == MEM_BLACK)
4477 w->color = MEM_RED;
4478 x = x->parent;
4480 else
4482 if (w->left->color == MEM_BLACK)
4484 w->right->color = MEM_BLACK;
4485 w->color = MEM_RED;
4486 mem_rotate_left (w);
4487 w = x->parent->left;
4490 w->color = x->parent->color;
4491 x->parent->color = MEM_BLACK;
4492 w->left->color = MEM_BLACK;
4493 mem_rotate_right (x->parent);
4494 x = mem_root;
4499 x->color = MEM_BLACK;
4503 /* Value is non-zero if P is a pointer to a live Lisp string on
4504 the heap. M is a pointer to the mem_block for P. */
4506 static bool
4507 live_string_p (struct mem_node *m, void *p)
4509 if (m->type == MEM_TYPE_STRING)
4511 struct string_block *b = m->start;
4512 ptrdiff_t offset = (char *) p - (char *) &b->strings[0];
4514 /* P must point to the start of a Lisp_String structure, and it
4515 must not be on the free-list. */
4516 return (offset >= 0
4517 && offset % sizeof b->strings[0] == 0
4518 && offset < (STRING_BLOCK_SIZE * sizeof b->strings[0])
4519 && ((struct Lisp_String *) p)->data != NULL);
4521 else
4522 return 0;
4526 /* Value is non-zero if P is a pointer to a live Lisp cons on
4527 the heap. M is a pointer to the mem_block for P. */
4529 static bool
4530 live_cons_p (struct mem_node *m, void *p)
4532 if (m->type == MEM_TYPE_CONS)
4534 struct cons_block *b = m->start;
4535 ptrdiff_t offset = (char *) p - (char *) &b->conses[0];
4537 /* P must point to the start of a Lisp_Cons, not be
4538 one of the unused cells in the current cons block,
4539 and not be on the free-list. */
4540 return (offset >= 0
4541 && offset % sizeof b->conses[0] == 0
4542 && offset < (CONS_BLOCK_SIZE * sizeof b->conses[0])
4543 && (b != cons_block
4544 || offset / sizeof b->conses[0] < cons_block_index)
4545 && !EQ (((struct Lisp_Cons *) p)->car, Vdead));
4547 else
4548 return 0;
4552 /* Value is non-zero if P is a pointer to a live Lisp symbol on
4553 the heap. M is a pointer to the mem_block for P. */
4555 static bool
4556 live_symbol_p (struct mem_node *m, void *p)
4558 if (m->type == MEM_TYPE_SYMBOL)
4560 struct symbol_block *b = m->start;
4561 ptrdiff_t offset = (char *) p - (char *) &b->symbols[0];
4563 /* P must point to the start of a Lisp_Symbol, not be
4564 one of the unused cells in the current symbol block,
4565 and not be on the free-list. */
4566 return (offset >= 0
4567 && offset % sizeof b->symbols[0] == 0
4568 && offset < (SYMBOL_BLOCK_SIZE * sizeof b->symbols[0])
4569 && (b != symbol_block
4570 || offset / sizeof b->symbols[0] < symbol_block_index)
4571 && !EQ (((struct Lisp_Symbol *)p)->function, Vdead));
4573 else
4574 return 0;
4578 /* Value is non-zero if P is a pointer to a live Lisp float on
4579 the heap. M is a pointer to the mem_block for P. */
4581 static bool
4582 live_float_p (struct mem_node *m, void *p)
4584 if (m->type == MEM_TYPE_FLOAT)
4586 struct float_block *b = m->start;
4587 ptrdiff_t offset = (char *) p - (char *) &b->floats[0];
4589 /* P must point to the start of a Lisp_Float and not be
4590 one of the unused cells in the current float block. */
4591 return (offset >= 0
4592 && offset % sizeof b->floats[0] == 0
4593 && offset < (FLOAT_BLOCK_SIZE * sizeof b->floats[0])
4594 && (b != float_block
4595 || offset / sizeof b->floats[0] < float_block_index));
4597 else
4598 return 0;
4602 /* Value is non-zero if P is a pointer to a live Lisp Misc on
4603 the heap. M is a pointer to the mem_block for P. */
4605 static bool
4606 live_misc_p (struct mem_node *m, void *p)
4608 if (m->type == MEM_TYPE_MISC)
4610 struct marker_block *b = m->start;
4611 ptrdiff_t offset = (char *) p - (char *) &b->markers[0];
4613 /* P must point to the start of a Lisp_Misc, not be
4614 one of the unused cells in the current misc block,
4615 and not be on the free-list. */
4616 return (offset >= 0
4617 && offset % sizeof b->markers[0] == 0
4618 && offset < (MARKER_BLOCK_SIZE * sizeof b->markers[0])
4619 && (b != marker_block
4620 || offset / sizeof b->markers[0] < marker_block_index)
4621 && ((union Lisp_Misc *) p)->u_any.type != Lisp_Misc_Free);
4623 else
4624 return 0;
4628 /* Value is non-zero if P is a pointer to a live vector-like object.
4629 M is a pointer to the mem_block for P. */
4631 static bool
4632 live_vector_p (struct mem_node *m, void *p)
4634 if (m->type == MEM_TYPE_VECTOR_BLOCK)
4636 /* This memory node corresponds to a vector block. */
4637 struct vector_block *block = m->start;
4638 struct Lisp_Vector *vector = (struct Lisp_Vector *) block->data;
4640 /* P is in the block's allocation range. Scan the block
4641 up to P and see whether P points to the start of some
4642 vector which is not on a free list. FIXME: check whether
4643 some allocation patterns (probably a lot of short vectors)
4644 may cause a substantial overhead of this loop. */
4645 while (VECTOR_IN_BLOCK (vector, block)
4646 && vector <= (struct Lisp_Vector *) p)
4648 if (!PSEUDOVECTOR_TYPEP (&vector->header, PVEC_FREE) && vector == p)
4649 return 1;
4650 else
4651 vector = ADVANCE (vector, vector_nbytes (vector));
4654 else if (m->type == MEM_TYPE_VECTORLIKE && p == large_vector_vec (m->start))
4655 /* This memory node corresponds to a large vector. */
4656 return 1;
4657 return 0;
4661 /* Value is non-zero if P is a pointer to a live buffer. M is a
4662 pointer to the mem_block for P. */
4664 static bool
4665 live_buffer_p (struct mem_node *m, void *p)
4667 /* P must point to the start of the block, and the buffer
4668 must not have been killed. */
4669 return (m->type == MEM_TYPE_BUFFER
4670 && p == m->start
4671 && !NILP (((struct buffer *) p)->name_));
4674 /* Mark OBJ if we can prove it's a Lisp_Object. */
4676 static void
4677 mark_maybe_object (Lisp_Object obj)
4679 #if USE_VALGRIND
4680 if (valgrind_p)
4681 VALGRIND_MAKE_MEM_DEFINED (&obj, sizeof (obj));
4682 #endif
4684 if (INTEGERP (obj))
4685 return;
4687 void *po = XPNTR (obj);
4688 struct mem_node *m = mem_find (po);
4690 if (m != MEM_NIL)
4692 bool mark_p = false;
4694 switch (XTYPE (obj))
4696 case Lisp_String:
4697 mark_p = (live_string_p (m, po)
4698 && !STRING_MARKED_P ((struct Lisp_String *) po));
4699 break;
4701 case Lisp_Cons:
4702 mark_p = (live_cons_p (m, po) && !CONS_MARKED_P (XCONS (obj)));
4703 break;
4705 case Lisp_Symbol:
4706 mark_p = (live_symbol_p (m, po) && !XSYMBOL (obj)->gcmarkbit);
4707 break;
4709 case Lisp_Float:
4710 mark_p = (live_float_p (m, po) && !FLOAT_MARKED_P (XFLOAT (obj)));
4711 break;
4713 case Lisp_Vectorlike:
4714 /* Note: can't check BUFFERP before we know it's a
4715 buffer because checking that dereferences the pointer
4716 PO which might point anywhere. */
4717 if (live_vector_p (m, po))
4718 mark_p = !SUBRP (obj) && !VECTOR_MARKED_P (XVECTOR (obj));
4719 else if (live_buffer_p (m, po))
4720 mark_p = BUFFERP (obj) && !VECTOR_MARKED_P (XBUFFER (obj));
4721 break;
4723 case Lisp_Misc:
4724 mark_p = (live_misc_p (m, po) && !XMISCANY (obj)->gcmarkbit);
4725 break;
4727 default:
4728 break;
4731 if (mark_p)
4732 mark_object (obj);
4736 /* Return true if P can point to Lisp data, and false otherwise.
4737 Symbols are implemented via offsets not pointers, but the offsets
4738 are also multiples of GCALIGNMENT. */
4740 static bool
4741 maybe_lisp_pointer (void *p)
4743 return (uintptr_t) p % GCALIGNMENT == 0;
4746 #ifndef HAVE_MODULES
4747 enum { HAVE_MODULES = false };
4748 #endif
4750 /* If P points to Lisp data, mark that as live if it isn't already
4751 marked. */
4753 static void
4754 mark_maybe_pointer (void *p)
4756 struct mem_node *m;
4758 #if USE_VALGRIND
4759 if (valgrind_p)
4760 VALGRIND_MAKE_MEM_DEFINED (&p, sizeof (p));
4761 #endif
4763 if (sizeof (Lisp_Object) == sizeof (void *) || !HAVE_MODULES)
4765 if (!maybe_lisp_pointer (p))
4766 return;
4768 else
4770 /* For the wide-int case, also mark emacs_value tagged pointers,
4771 which can be generated by emacs-module.c's value_to_lisp. */
4772 p = (void *) ((uintptr_t) p & ~(GCALIGNMENT - 1));
4775 m = mem_find (p);
4776 if (m != MEM_NIL)
4778 Lisp_Object obj = Qnil;
4780 switch (m->type)
4782 case MEM_TYPE_NON_LISP:
4783 case MEM_TYPE_SPARE:
4784 /* Nothing to do; not a pointer to Lisp memory. */
4785 break;
4787 case MEM_TYPE_BUFFER:
4788 if (live_buffer_p (m, p) && !VECTOR_MARKED_P ((struct buffer *)p))
4789 XSETVECTOR (obj, p);
4790 break;
4792 case MEM_TYPE_CONS:
4793 if (live_cons_p (m, p) && !CONS_MARKED_P ((struct Lisp_Cons *) p))
4794 XSETCONS (obj, p);
4795 break;
4797 case MEM_TYPE_STRING:
4798 if (live_string_p (m, p)
4799 && !STRING_MARKED_P ((struct Lisp_String *) p))
4800 XSETSTRING (obj, p);
4801 break;
4803 case MEM_TYPE_MISC:
4804 if (live_misc_p (m, p) && !((struct Lisp_Free *) p)->gcmarkbit)
4805 XSETMISC (obj, p);
4806 break;
4808 case MEM_TYPE_SYMBOL:
4809 if (live_symbol_p (m, p) && !((struct Lisp_Symbol *) p)->gcmarkbit)
4810 XSETSYMBOL (obj, p);
4811 break;
4813 case MEM_TYPE_FLOAT:
4814 if (live_float_p (m, p) && !FLOAT_MARKED_P (p))
4815 XSETFLOAT (obj, p);
4816 break;
4818 case MEM_TYPE_VECTORLIKE:
4819 case MEM_TYPE_VECTOR_BLOCK:
4820 if (live_vector_p (m, p))
4822 Lisp_Object tem;
4823 XSETVECTOR (tem, p);
4824 if (!SUBRP (tem) && !VECTOR_MARKED_P (XVECTOR (tem)))
4825 obj = tem;
4827 break;
4829 default:
4830 emacs_abort ();
4833 if (!NILP (obj))
4834 mark_object (obj);
4839 /* Alignment of pointer values. Use alignof, as it sometimes returns
4840 a smaller alignment than GCC's __alignof__ and mark_memory might
4841 miss objects if __alignof__ were used. */
4842 #define GC_POINTER_ALIGNMENT alignof (void *)
4844 /* Mark Lisp objects referenced from the address range START+OFFSET..END
4845 or END+OFFSET..START. */
4847 static void ATTRIBUTE_NO_SANITIZE_ADDRESS
4848 mark_memory (void *start, void *end)
4850 char *pp;
4852 /* Make START the pointer to the start of the memory region,
4853 if it isn't already. */
4854 if (end < start)
4856 void *tem = start;
4857 start = end;
4858 end = tem;
4861 eassert (((uintptr_t) start) % GC_POINTER_ALIGNMENT == 0);
4863 /* Mark Lisp data pointed to. This is necessary because, in some
4864 situations, the C compiler optimizes Lisp objects away, so that
4865 only a pointer to them remains. Example:
4867 DEFUN ("testme", Ftestme, Stestme, 0, 0, 0, "")
4870 Lisp_Object obj = build_string ("test");
4871 struct Lisp_String *s = XSTRING (obj);
4872 Fgarbage_collect ();
4873 fprintf (stderr, "test '%s'\n", s->data);
4874 return Qnil;
4877 Here, `obj' isn't really used, and the compiler optimizes it
4878 away. The only reference to the life string is through the
4879 pointer `s'. */
4881 for (pp = start; (void *) pp < end; pp += GC_POINTER_ALIGNMENT)
4883 mark_maybe_pointer (*(void **) pp);
4884 mark_maybe_object (*(Lisp_Object *) pp);
4888 #if !defined GC_SAVE_REGISTERS_ON_STACK && !defined GC_SETJMP_WORKS
4890 static bool setjmp_tested_p;
4891 static int longjmps_done;
4893 #define SETJMP_WILL_LIKELY_WORK "\
4895 Emacs garbage collector has been changed to use conservative stack\n\
4896 marking. Emacs has determined that the method it uses to do the\n\
4897 marking will likely work on your system, but this isn't sure.\n\
4899 If you are a system-programmer, or can get the help of a local wizard\n\
4900 who is, please take a look at the function mark_stack in alloc.c, and\n\
4901 verify that the methods used are appropriate for your system.\n\
4903 Please mail the result to <emacs-devel@gnu.org>.\n\
4906 #define SETJMP_WILL_NOT_WORK "\
4908 Emacs garbage collector has been changed to use conservative stack\n\
4909 marking. Emacs has determined that the default method it uses to do the\n\
4910 marking will not work on your system. We will need a system-dependent\n\
4911 solution for your system.\n\
4913 Please take a look at the function mark_stack in alloc.c, and\n\
4914 try to find a way to make it work on your system.\n\
4916 Note that you may get false negatives, depending on the compiler.\n\
4917 In particular, you need to use -O with GCC for this test.\n\
4919 Please mail the result to <emacs-devel@gnu.org>.\n\
4923 /* Perform a quick check if it looks like setjmp saves registers in a
4924 jmp_buf. Print a message to stderr saying so. When this test
4925 succeeds, this is _not_ a proof that setjmp is sufficient for
4926 conservative stack marking. Only the sources or a disassembly
4927 can prove that. */
4929 static void
4930 test_setjmp (void)
4932 char buf[10];
4933 register int x;
4934 sys_jmp_buf jbuf;
4936 /* Arrange for X to be put in a register. */
4937 sprintf (buf, "1");
4938 x = strlen (buf);
4939 x = 2 * x - 1;
4941 sys_setjmp (jbuf);
4942 if (longjmps_done == 1)
4944 /* Came here after the longjmp at the end of the function.
4946 If x == 1, the longjmp has restored the register to its
4947 value before the setjmp, and we can hope that setjmp
4948 saves all such registers in the jmp_buf, although that
4949 isn't sure.
4951 For other values of X, either something really strange is
4952 taking place, or the setjmp just didn't save the register. */
4954 if (x == 1)
4955 fprintf (stderr, SETJMP_WILL_LIKELY_WORK);
4956 else
4958 fprintf (stderr, SETJMP_WILL_NOT_WORK);
4959 exit (1);
4963 ++longjmps_done;
4964 x = 2;
4965 if (longjmps_done == 1)
4966 sys_longjmp (jbuf, 1);
4969 #endif /* not GC_SAVE_REGISTERS_ON_STACK && not GC_SETJMP_WORKS */
4972 /* Mark live Lisp objects on the C stack.
4974 There are several system-dependent problems to consider when
4975 porting this to new architectures:
4977 Processor Registers
4979 We have to mark Lisp objects in CPU registers that can hold local
4980 variables or are used to pass parameters.
4982 If GC_SAVE_REGISTERS_ON_STACK is defined, it should expand to
4983 something that either saves relevant registers on the stack, or
4984 calls mark_maybe_object passing it each register's contents.
4986 If GC_SAVE_REGISTERS_ON_STACK is not defined, the current
4987 implementation assumes that calling setjmp saves registers we need
4988 to see in a jmp_buf which itself lies on the stack. This doesn't
4989 have to be true! It must be verified for each system, possibly
4990 by taking a look at the source code of setjmp.
4992 If __builtin_unwind_init is available (defined by GCC >= 2.8) we
4993 can use it as a machine independent method to store all registers
4994 to the stack. In this case the macros described in the previous
4995 two paragraphs are not used.
4997 Stack Layout
4999 Architectures differ in the way their processor stack is organized.
5000 For example, the stack might look like this
5002 +----------------+
5003 | Lisp_Object | size = 4
5004 +----------------+
5005 | something else | size = 2
5006 +----------------+
5007 | Lisp_Object | size = 4
5008 +----------------+
5009 | ... |
5011 In such a case, not every Lisp_Object will be aligned equally. To
5012 find all Lisp_Object on the stack it won't be sufficient to walk
5013 the stack in steps of 4 bytes. Instead, two passes will be
5014 necessary, one starting at the start of the stack, and a second
5015 pass starting at the start of the stack + 2. Likewise, if the
5016 minimal alignment of Lisp_Objects on the stack is 1, four passes
5017 would be necessary, each one starting with one byte more offset
5018 from the stack start. */
5020 static void
5021 mark_stack (void *end)
5024 /* This assumes that the stack is a contiguous region in memory. If
5025 that's not the case, something has to be done here to iterate
5026 over the stack segments. */
5027 mark_memory (stack_base, end);
5029 /* Allow for marking a secondary stack, like the register stack on the
5030 ia64. */
5031 #ifdef GC_MARK_SECONDARY_STACK
5032 GC_MARK_SECONDARY_STACK ();
5033 #endif
5036 static bool
5037 c_symbol_p (struct Lisp_Symbol *sym)
5039 char *lispsym_ptr = (char *) lispsym;
5040 char *sym_ptr = (char *) sym;
5041 ptrdiff_t lispsym_offset = sym_ptr - lispsym_ptr;
5042 return 0 <= lispsym_offset && lispsym_offset < sizeof lispsym;
5045 /* Determine whether it is safe to access memory at address P. */
5046 static int
5047 valid_pointer_p (void *p)
5049 #ifdef WINDOWSNT
5050 return w32_valid_pointer_p (p, 16);
5051 #else
5053 if (ADDRESS_SANITIZER)
5054 return p ? -1 : 0;
5056 int fd[2];
5058 /* Obviously, we cannot just access it (we would SEGV trying), so we
5059 trick the o/s to tell us whether p is a valid pointer.
5060 Unfortunately, we cannot use NULL_DEVICE here, as emacs_write may
5061 not validate p in that case. */
5063 if (emacs_pipe (fd) == 0)
5065 bool valid = emacs_write (fd[1], p, 16) == 16;
5066 emacs_close (fd[1]);
5067 emacs_close (fd[0]);
5068 return valid;
5071 return -1;
5072 #endif
5075 /* Return 2 if OBJ is a killed or special buffer object, 1 if OBJ is a
5076 valid lisp object, 0 if OBJ is NOT a valid lisp object, or -1 if we
5077 cannot validate OBJ. This function can be quite slow, so its primary
5078 use is the manual debugging. The only exception is print_object, where
5079 we use it to check whether the memory referenced by the pointer of
5080 Lisp_Save_Value object contains valid objects. */
5083 valid_lisp_object_p (Lisp_Object obj)
5085 if (INTEGERP (obj))
5086 return 1;
5088 void *p = XPNTR (obj);
5089 if (PURE_P (p))
5090 return 1;
5092 if (SYMBOLP (obj) && c_symbol_p (p))
5093 return ((char *) p - (char *) lispsym) % sizeof lispsym[0] == 0;
5095 if (p == &buffer_defaults || p == &buffer_local_symbols)
5096 return 2;
5098 struct mem_node *m = mem_find (p);
5100 if (m == MEM_NIL)
5102 int valid = valid_pointer_p (p);
5103 if (valid <= 0)
5104 return valid;
5106 if (SUBRP (obj))
5107 return 1;
5109 return 0;
5112 switch (m->type)
5114 case MEM_TYPE_NON_LISP:
5115 case MEM_TYPE_SPARE:
5116 return 0;
5118 case MEM_TYPE_BUFFER:
5119 return live_buffer_p (m, p) ? 1 : 2;
5121 case MEM_TYPE_CONS:
5122 return live_cons_p (m, p);
5124 case MEM_TYPE_STRING:
5125 return live_string_p (m, p);
5127 case MEM_TYPE_MISC:
5128 return live_misc_p (m, p);
5130 case MEM_TYPE_SYMBOL:
5131 return live_symbol_p (m, p);
5133 case MEM_TYPE_FLOAT:
5134 return live_float_p (m, p);
5136 case MEM_TYPE_VECTORLIKE:
5137 case MEM_TYPE_VECTOR_BLOCK:
5138 return live_vector_p (m, p);
5140 default:
5141 break;
5144 return 0;
5147 /***********************************************************************
5148 Pure Storage Management
5149 ***********************************************************************/
5151 /* Allocate room for SIZE bytes from pure Lisp storage and return a
5152 pointer to it. TYPE is the Lisp type for which the memory is
5153 allocated. TYPE < 0 means it's not used for a Lisp object. */
5155 static void *
5156 pure_alloc (size_t size, int type)
5158 void *result;
5160 again:
5161 if (type >= 0)
5163 /* Allocate space for a Lisp object from the beginning of the free
5164 space with taking account of alignment. */
5165 result = ALIGN (purebeg + pure_bytes_used_lisp, GCALIGNMENT);
5166 pure_bytes_used_lisp = ((char *)result - (char *)purebeg) + size;
5168 else
5170 /* Allocate space for a non-Lisp object from the end of the free
5171 space. */
5172 pure_bytes_used_non_lisp += size;
5173 result = purebeg + pure_size - pure_bytes_used_non_lisp;
5175 pure_bytes_used = pure_bytes_used_lisp + pure_bytes_used_non_lisp;
5177 if (pure_bytes_used <= pure_size)
5178 return result;
5180 /* Don't allocate a large amount here,
5181 because it might get mmap'd and then its address
5182 might not be usable. */
5183 purebeg = xmalloc (10000);
5184 pure_size = 10000;
5185 pure_bytes_used_before_overflow += pure_bytes_used - size;
5186 pure_bytes_used = 0;
5187 pure_bytes_used_lisp = pure_bytes_used_non_lisp = 0;
5188 goto again;
5192 /* Print a warning if PURESIZE is too small. */
5194 void
5195 check_pure_size (void)
5197 if (pure_bytes_used_before_overflow)
5198 message (("emacs:0:Pure Lisp storage overflow (approx. %"pI"d"
5199 " bytes needed)"),
5200 pure_bytes_used + pure_bytes_used_before_overflow);
5204 /* Find the byte sequence {DATA[0], ..., DATA[NBYTES-1], '\0'} from
5205 the non-Lisp data pool of the pure storage, and return its start
5206 address. Return NULL if not found. */
5208 static char *
5209 find_string_data_in_pure (const char *data, ptrdiff_t nbytes)
5211 int i;
5212 ptrdiff_t skip, bm_skip[256], last_char_skip, infinity, start, start_max;
5213 const unsigned char *p;
5214 char *non_lisp_beg;
5216 if (pure_bytes_used_non_lisp <= nbytes)
5217 return NULL;
5219 /* Set up the Boyer-Moore table. */
5220 skip = nbytes + 1;
5221 for (i = 0; i < 256; i++)
5222 bm_skip[i] = skip;
5224 p = (const unsigned char *) data;
5225 while (--skip > 0)
5226 bm_skip[*p++] = skip;
5228 last_char_skip = bm_skip['\0'];
5230 non_lisp_beg = purebeg + pure_size - pure_bytes_used_non_lisp;
5231 start_max = pure_bytes_used_non_lisp - (nbytes + 1);
5233 /* See the comments in the function `boyer_moore' (search.c) for the
5234 use of `infinity'. */
5235 infinity = pure_bytes_used_non_lisp + 1;
5236 bm_skip['\0'] = infinity;
5238 p = (const unsigned char *) non_lisp_beg + nbytes;
5239 start = 0;
5242 /* Check the last character (== '\0'). */
5245 start += bm_skip[*(p + start)];
5247 while (start <= start_max);
5249 if (start < infinity)
5250 /* Couldn't find the last character. */
5251 return NULL;
5253 /* No less than `infinity' means we could find the last
5254 character at `p[start - infinity]'. */
5255 start -= infinity;
5257 /* Check the remaining characters. */
5258 if (memcmp (data, non_lisp_beg + start, nbytes) == 0)
5259 /* Found. */
5260 return non_lisp_beg + start;
5262 start += last_char_skip;
5264 while (start <= start_max);
5266 return NULL;
5270 /* Return a string allocated in pure space. DATA is a buffer holding
5271 NCHARS characters, and NBYTES bytes of string data. MULTIBYTE
5272 means make the result string multibyte.
5274 Must get an error if pure storage is full, since if it cannot hold
5275 a large string it may be able to hold conses that point to that
5276 string; then the string is not protected from gc. */
5278 Lisp_Object
5279 make_pure_string (const char *data,
5280 ptrdiff_t nchars, ptrdiff_t nbytes, bool multibyte)
5282 Lisp_Object string;
5283 struct Lisp_String *s = pure_alloc (sizeof *s, Lisp_String);
5284 s->data = (unsigned char *) find_string_data_in_pure (data, nbytes);
5285 if (s->data == NULL)
5287 s->data = pure_alloc (nbytes + 1, -1);
5288 memcpy (s->data, data, nbytes);
5289 s->data[nbytes] = '\0';
5291 s->size = nchars;
5292 s->size_byte = multibyte ? nbytes : -1;
5293 s->intervals = NULL;
5294 XSETSTRING (string, s);
5295 return string;
5298 /* Return a string allocated in pure space. Do not
5299 allocate the string data, just point to DATA. */
5301 Lisp_Object
5302 make_pure_c_string (const char *data, ptrdiff_t nchars)
5304 Lisp_Object string;
5305 struct Lisp_String *s = pure_alloc (sizeof *s, Lisp_String);
5306 s->size = nchars;
5307 s->size_byte = -1;
5308 s->data = (unsigned char *) data;
5309 s->intervals = NULL;
5310 XSETSTRING (string, s);
5311 return string;
5314 static Lisp_Object purecopy (Lisp_Object obj);
5316 /* Return a cons allocated from pure space. Give it pure copies
5317 of CAR as car and CDR as cdr. */
5319 Lisp_Object
5320 pure_cons (Lisp_Object car, Lisp_Object cdr)
5322 Lisp_Object new;
5323 struct Lisp_Cons *p = pure_alloc (sizeof *p, Lisp_Cons);
5324 XSETCONS (new, p);
5325 XSETCAR (new, purecopy (car));
5326 XSETCDR (new, purecopy (cdr));
5327 return new;
5331 /* Value is a float object with value NUM allocated from pure space. */
5333 static Lisp_Object
5334 make_pure_float (double num)
5336 Lisp_Object new;
5337 struct Lisp_Float *p = pure_alloc (sizeof *p, Lisp_Float);
5338 XSETFLOAT (new, p);
5339 XFLOAT_INIT (new, num);
5340 return new;
5344 /* Return a vector with room for LEN Lisp_Objects allocated from
5345 pure space. */
5347 static Lisp_Object
5348 make_pure_vector (ptrdiff_t len)
5350 Lisp_Object new;
5351 size_t size = header_size + len * word_size;
5352 struct Lisp_Vector *p = pure_alloc (size, Lisp_Vectorlike);
5353 XSETVECTOR (new, p);
5354 XVECTOR (new)->header.size = len;
5355 return new;
5358 DEFUN ("purecopy", Fpurecopy, Spurecopy, 1, 1, 0,
5359 doc: /* Make a copy of object OBJ in pure storage.
5360 Recursively copies contents of vectors and cons cells.
5361 Does not copy symbols. Copies strings without text properties. */)
5362 (register Lisp_Object obj)
5364 if (NILP (Vpurify_flag))
5365 return obj;
5366 else if (MARKERP (obj) || OVERLAYP (obj)
5367 || HASH_TABLE_P (obj) || SYMBOLP (obj))
5368 /* Can't purify those. */
5369 return obj;
5370 else
5371 return purecopy (obj);
5374 static Lisp_Object
5375 purecopy (Lisp_Object obj)
5377 if (INTEGERP (obj)
5378 || (! SYMBOLP (obj) && PURE_P (XPNTR_OR_SYMBOL_OFFSET (obj)))
5379 || SUBRP (obj))
5380 return obj; /* Already pure. */
5382 if (STRINGP (obj) && XSTRING (obj)->intervals)
5383 message_with_string ("Dropping text-properties while making string `%s' pure",
5384 obj, true);
5386 if (HASH_TABLE_P (Vpurify_flag)) /* Hash consing. */
5388 Lisp_Object tmp = Fgethash (obj, Vpurify_flag, Qnil);
5389 if (!NILP (tmp))
5390 return tmp;
5393 if (CONSP (obj))
5394 obj = pure_cons (XCAR (obj), XCDR (obj));
5395 else if (FLOATP (obj))
5396 obj = make_pure_float (XFLOAT_DATA (obj));
5397 else if (STRINGP (obj))
5398 obj = make_pure_string (SSDATA (obj), SCHARS (obj),
5399 SBYTES (obj),
5400 STRING_MULTIBYTE (obj));
5401 else if (COMPILEDP (obj) || VECTORP (obj) || HASH_TABLE_P (obj))
5403 struct Lisp_Vector *objp = XVECTOR (obj);
5404 ptrdiff_t nbytes = vector_nbytes (objp);
5405 struct Lisp_Vector *vec = pure_alloc (nbytes, Lisp_Vectorlike);
5406 register ptrdiff_t i;
5407 ptrdiff_t size = ASIZE (obj);
5408 if (size & PSEUDOVECTOR_FLAG)
5409 size &= PSEUDOVECTOR_SIZE_MASK;
5410 memcpy (vec, objp, nbytes);
5411 for (i = 0; i < size; i++)
5412 vec->contents[i] = purecopy (vec->contents[i]);
5413 XSETVECTOR (obj, vec);
5415 else if (SYMBOLP (obj))
5417 if (!XSYMBOL (obj)->pinned && !c_symbol_p (XSYMBOL (obj)))
5418 { /* We can't purify them, but they appear in many pure objects.
5419 Mark them as `pinned' so we know to mark them at every GC cycle. */
5420 XSYMBOL (obj)->pinned = true;
5421 symbol_block_pinned = symbol_block;
5423 /* Don't hash-cons it. */
5424 return obj;
5426 else
5428 AUTO_STRING (fmt, "Don't know how to purify: %S");
5429 Fsignal (Qerror, list1 (CALLN (Fformat, fmt, obj)));
5432 if (HASH_TABLE_P (Vpurify_flag)) /* Hash consing. */
5433 Fputhash (obj, obj, Vpurify_flag);
5435 return obj;
5440 /***********************************************************************
5441 Protection from GC
5442 ***********************************************************************/
5444 /* Put an entry in staticvec, pointing at the variable with address
5445 VARADDRESS. */
5447 void
5448 staticpro (Lisp_Object *varaddress)
5450 if (staticidx >= NSTATICS)
5451 fatal ("NSTATICS too small; try increasing and recompiling Emacs.");
5452 staticvec[staticidx++] = varaddress;
5456 /***********************************************************************
5457 Protection from GC
5458 ***********************************************************************/
5460 /* Temporarily prevent garbage collection. */
5462 ptrdiff_t
5463 inhibit_garbage_collection (void)
5465 ptrdiff_t count = SPECPDL_INDEX ();
5467 specbind (Qgc_cons_threshold, make_number (MOST_POSITIVE_FIXNUM));
5468 return count;
5471 /* Used to avoid possible overflows when
5472 converting from C to Lisp integers. */
5474 static Lisp_Object
5475 bounded_number (EMACS_INT number)
5477 return make_number (min (MOST_POSITIVE_FIXNUM, number));
5480 /* Calculate total bytes of live objects. */
5482 static size_t
5483 total_bytes_of_live_objects (void)
5485 size_t tot = 0;
5486 tot += total_conses * sizeof (struct Lisp_Cons);
5487 tot += total_symbols * sizeof (struct Lisp_Symbol);
5488 tot += total_markers * sizeof (union Lisp_Misc);
5489 tot += total_string_bytes;
5490 tot += total_vector_slots * word_size;
5491 tot += total_floats * sizeof (struct Lisp_Float);
5492 tot += total_intervals * sizeof (struct interval);
5493 tot += total_strings * sizeof (struct Lisp_String);
5494 return tot;
5497 #ifdef HAVE_WINDOW_SYSTEM
5499 /* Remove unmarked font-spec and font-entity objects from ENTRY, which is
5500 (DRIVER-TYPE NUM-FRAMES FONT-CACHE-DATA ...), and return changed entry. */
5502 static Lisp_Object
5503 compact_font_cache_entry (Lisp_Object entry)
5505 Lisp_Object tail, *prev = &entry;
5507 for (tail = entry; CONSP (tail); tail = XCDR (tail))
5509 bool drop = 0;
5510 Lisp_Object obj = XCAR (tail);
5512 /* Consider OBJ if it is (font-spec . [font-entity font-entity ...]). */
5513 if (CONSP (obj) && GC_FONT_SPEC_P (XCAR (obj))
5514 && !VECTOR_MARKED_P (GC_XFONT_SPEC (XCAR (obj)))
5515 /* Don't use VECTORP here, as that calls ASIZE, which could
5516 hit assertion violation during GC. */
5517 && (VECTORLIKEP (XCDR (obj))
5518 && ! (gc_asize (XCDR (obj)) & PSEUDOVECTOR_FLAG)))
5520 ptrdiff_t i, size = gc_asize (XCDR (obj));
5521 Lisp_Object obj_cdr = XCDR (obj);
5523 /* If font-spec is not marked, most likely all font-entities
5524 are not marked too. But we must be sure that nothing is
5525 marked within OBJ before we really drop it. */
5526 for (i = 0; i < size; i++)
5528 Lisp_Object objlist;
5530 if (VECTOR_MARKED_P (GC_XFONT_ENTITY (AREF (obj_cdr, i))))
5531 break;
5533 objlist = AREF (AREF (obj_cdr, i), FONT_OBJLIST_INDEX);
5534 for (; CONSP (objlist); objlist = XCDR (objlist))
5536 Lisp_Object val = XCAR (objlist);
5537 struct font *font = GC_XFONT_OBJECT (val);
5539 if (!NILP (AREF (val, FONT_TYPE_INDEX))
5540 && VECTOR_MARKED_P(font))
5541 break;
5543 if (CONSP (objlist))
5545 /* Found a marked font, bail out. */
5546 break;
5550 if (i == size)
5552 /* No marked fonts were found, so this entire font
5553 entity can be dropped. */
5554 drop = 1;
5557 if (drop)
5558 *prev = XCDR (tail);
5559 else
5560 prev = xcdr_addr (tail);
5562 return entry;
5565 /* Compact font caches on all terminals and mark
5566 everything which is still here after compaction. */
5568 static void
5569 compact_font_caches (void)
5571 struct terminal *t;
5573 for (t = terminal_list; t; t = t->next_terminal)
5575 Lisp_Object cache = TERMINAL_FONT_CACHE (t);
5576 if (CONSP (cache))
5578 Lisp_Object entry;
5580 for (entry = XCDR (cache); CONSP (entry); entry = XCDR (entry))
5581 XSETCAR (entry, compact_font_cache_entry (XCAR (entry)));
5583 mark_object (cache);
5587 #else /* not HAVE_WINDOW_SYSTEM */
5589 #define compact_font_caches() (void)(0)
5591 #endif /* HAVE_WINDOW_SYSTEM */
5593 /* Remove (MARKER . DATA) entries with unmarked MARKER
5594 from buffer undo LIST and return changed list. */
5596 static Lisp_Object
5597 compact_undo_list (Lisp_Object list)
5599 Lisp_Object tail, *prev = &list;
5601 for (tail = list; CONSP (tail); tail = XCDR (tail))
5603 if (CONSP (XCAR (tail))
5604 && MARKERP (XCAR (XCAR (tail)))
5605 && !XMARKER (XCAR (XCAR (tail)))->gcmarkbit)
5606 *prev = XCDR (tail);
5607 else
5608 prev = xcdr_addr (tail);
5610 return list;
5613 static void
5614 mark_pinned_symbols (void)
5616 struct symbol_block *sblk;
5617 int lim = (symbol_block_pinned == symbol_block
5618 ? symbol_block_index : SYMBOL_BLOCK_SIZE);
5620 for (sblk = symbol_block_pinned; sblk; sblk = sblk->next)
5622 union aligned_Lisp_Symbol *sym = sblk->symbols, *end = sym + lim;
5623 for (; sym < end; ++sym)
5624 if (sym->s.pinned)
5625 mark_object (make_lisp_symbol (&sym->s));
5627 lim = SYMBOL_BLOCK_SIZE;
5631 /* Subroutine of Fgarbage_collect that does most of the work. It is a
5632 separate function so that we could limit mark_stack in searching
5633 the stack frames below this function, thus avoiding the rare cases
5634 where mark_stack finds values that look like live Lisp objects on
5635 portions of stack that couldn't possibly contain such live objects.
5636 For more details of this, see the discussion at
5637 http://lists.gnu.org/archive/html/emacs-devel/2014-05/msg00270.html. */
5638 static Lisp_Object
5639 garbage_collect_1 (void *end)
5641 struct buffer *nextb;
5642 char stack_top_variable;
5643 ptrdiff_t i;
5644 bool message_p;
5645 ptrdiff_t count = SPECPDL_INDEX ();
5646 struct timespec start;
5647 Lisp_Object retval = Qnil;
5648 size_t tot_before = 0;
5650 if (abort_on_gc)
5651 emacs_abort ();
5653 /* Can't GC if pure storage overflowed because we can't determine
5654 if something is a pure object or not. */
5655 if (pure_bytes_used_before_overflow)
5656 return Qnil;
5658 /* Record this function, so it appears on the profiler's backtraces. */
5659 record_in_backtrace (QAutomatic_GC, 0, 0);
5661 check_cons_list ();
5663 /* Don't keep undo information around forever.
5664 Do this early on, so it is no problem if the user quits. */
5665 FOR_EACH_BUFFER (nextb)
5666 compact_buffer (nextb);
5668 if (profiler_memory_running)
5669 tot_before = total_bytes_of_live_objects ();
5671 start = current_timespec ();
5673 /* In case user calls debug_print during GC,
5674 don't let that cause a recursive GC. */
5675 consing_since_gc = 0;
5677 /* Save what's currently displayed in the echo area. Don't do that
5678 if we are GC'ing because we've run out of memory, since
5679 push_message will cons, and we might have no memory for that. */
5680 if (NILP (Vmemory_full))
5682 message_p = push_message ();
5683 record_unwind_protect_void (pop_message_unwind);
5685 else
5686 message_p = false;
5688 /* Save a copy of the contents of the stack, for debugging. */
5689 #if MAX_SAVE_STACK > 0
5690 if (NILP (Vpurify_flag))
5692 char *stack;
5693 ptrdiff_t stack_size;
5694 if (&stack_top_variable < stack_bottom)
5696 stack = &stack_top_variable;
5697 stack_size = stack_bottom - &stack_top_variable;
5699 else
5701 stack = stack_bottom;
5702 stack_size = &stack_top_variable - stack_bottom;
5704 if (stack_size <= MAX_SAVE_STACK)
5706 if (stack_copy_size < stack_size)
5708 stack_copy = xrealloc (stack_copy, stack_size);
5709 stack_copy_size = stack_size;
5711 no_sanitize_memcpy (stack_copy, stack, stack_size);
5714 #endif /* MAX_SAVE_STACK > 0 */
5716 if (garbage_collection_messages)
5717 message1_nolog ("Garbage collecting...");
5719 block_input ();
5721 shrink_regexp_cache ();
5723 gc_in_progress = 1;
5725 /* Mark all the special slots that serve as the roots of accessibility. */
5727 mark_buffer (&buffer_defaults);
5728 mark_buffer (&buffer_local_symbols);
5730 for (i = 0; i < ARRAYELTS (lispsym); i++)
5731 mark_object (builtin_lisp_symbol (i));
5733 for (i = 0; i < staticidx; i++)
5734 mark_object (*staticvec[i]);
5736 mark_pinned_symbols ();
5737 mark_specpdl ();
5738 mark_terminals ();
5739 mark_kboards ();
5741 #ifdef USE_GTK
5742 xg_mark_data ();
5743 #endif
5745 mark_stack (end);
5748 struct handler *handler;
5749 for (handler = handlerlist; handler; handler = handler->next)
5751 mark_object (handler->tag_or_ch);
5752 mark_object (handler->val);
5755 #ifdef HAVE_WINDOW_SYSTEM
5756 mark_fringe_data ();
5757 #endif
5759 /* Everything is now marked, except for the data in font caches,
5760 undo lists, and finalizers. The first two are compacted by
5761 removing an items which aren't reachable otherwise. */
5763 compact_font_caches ();
5765 FOR_EACH_BUFFER (nextb)
5767 if (!EQ (BVAR (nextb, undo_list), Qt))
5768 bset_undo_list (nextb, compact_undo_list (BVAR (nextb, undo_list)));
5769 /* Now that we have stripped the elements that need not be
5770 in the undo_list any more, we can finally mark the list. */
5771 mark_object (BVAR (nextb, undo_list));
5774 /* Now pre-sweep finalizers. Here, we add any unmarked finalizers
5775 to doomed_finalizers so we can run their associated functions
5776 after GC. It's important to scan finalizers at this stage so
5777 that we can be sure that unmarked finalizers are really
5778 unreachable except for references from their associated functions
5779 and from other finalizers. */
5781 queue_doomed_finalizers (&doomed_finalizers, &finalizers);
5782 mark_finalizer_list (&doomed_finalizers);
5784 gc_sweep ();
5786 relocate_byte_stack ();
5788 /* Clear the mark bits that we set in certain root slots. */
5789 VECTOR_UNMARK (&buffer_defaults);
5790 VECTOR_UNMARK (&buffer_local_symbols);
5792 check_cons_list ();
5794 gc_in_progress = 0;
5796 unblock_input ();
5798 consing_since_gc = 0;
5799 if (gc_cons_threshold < GC_DEFAULT_THRESHOLD / 10)
5800 gc_cons_threshold = GC_DEFAULT_THRESHOLD / 10;
5802 gc_relative_threshold = 0;
5803 if (FLOATP (Vgc_cons_percentage))
5804 { /* Set gc_cons_combined_threshold. */
5805 double tot = total_bytes_of_live_objects ();
5807 tot *= XFLOAT_DATA (Vgc_cons_percentage);
5808 if (0 < tot)
5810 if (tot < TYPE_MAXIMUM (EMACS_INT))
5811 gc_relative_threshold = tot;
5812 else
5813 gc_relative_threshold = TYPE_MAXIMUM (EMACS_INT);
5817 if (garbage_collection_messages && NILP (Vmemory_full))
5819 if (message_p || minibuf_level > 0)
5820 restore_message ();
5821 else
5822 message1_nolog ("Garbage collecting...done");
5825 unbind_to (count, Qnil);
5827 Lisp_Object total[] = {
5828 list4 (Qconses, make_number (sizeof (struct Lisp_Cons)),
5829 bounded_number (total_conses),
5830 bounded_number (total_free_conses)),
5831 list4 (Qsymbols, make_number (sizeof (struct Lisp_Symbol)),
5832 bounded_number (total_symbols),
5833 bounded_number (total_free_symbols)),
5834 list4 (Qmiscs, make_number (sizeof (union Lisp_Misc)),
5835 bounded_number (total_markers),
5836 bounded_number (total_free_markers)),
5837 list4 (Qstrings, make_number (sizeof (struct Lisp_String)),
5838 bounded_number (total_strings),
5839 bounded_number (total_free_strings)),
5840 list3 (Qstring_bytes, make_number (1),
5841 bounded_number (total_string_bytes)),
5842 list3 (Qvectors,
5843 make_number (header_size + sizeof (Lisp_Object)),
5844 bounded_number (total_vectors)),
5845 list4 (Qvector_slots, make_number (word_size),
5846 bounded_number (total_vector_slots),
5847 bounded_number (total_free_vector_slots)),
5848 list4 (Qfloats, make_number (sizeof (struct Lisp_Float)),
5849 bounded_number (total_floats),
5850 bounded_number (total_free_floats)),
5851 list4 (Qintervals, make_number (sizeof (struct interval)),
5852 bounded_number (total_intervals),
5853 bounded_number (total_free_intervals)),
5854 list3 (Qbuffers, make_number (sizeof (struct buffer)),
5855 bounded_number (total_buffers)),
5857 #ifdef DOUG_LEA_MALLOC
5858 list4 (Qheap, make_number (1024),
5859 bounded_number ((mallinfo ().uordblks + 1023) >> 10),
5860 bounded_number ((mallinfo ().fordblks + 1023) >> 10)),
5861 #endif
5863 retval = CALLMANY (Flist, total);
5865 /* GC is complete: now we can run our finalizer callbacks. */
5866 run_finalizers (&doomed_finalizers);
5868 if (!NILP (Vpost_gc_hook))
5870 ptrdiff_t gc_count = inhibit_garbage_collection ();
5871 safe_run_hooks (Qpost_gc_hook);
5872 unbind_to (gc_count, Qnil);
5875 /* Accumulate statistics. */
5876 if (FLOATP (Vgc_elapsed))
5878 struct timespec since_start = timespec_sub (current_timespec (), start);
5879 Vgc_elapsed = make_float (XFLOAT_DATA (Vgc_elapsed)
5880 + timespectod (since_start));
5883 gcs_done++;
5885 /* Collect profiling data. */
5886 if (profiler_memory_running)
5888 size_t swept = 0;
5889 size_t tot_after = total_bytes_of_live_objects ();
5890 if (tot_before > tot_after)
5891 swept = tot_before - tot_after;
5892 malloc_probe (swept);
5895 return retval;
5898 DEFUN ("garbage-collect", Fgarbage_collect, Sgarbage_collect, 0, 0, "",
5899 doc: /* Reclaim storage for Lisp objects no longer needed.
5900 Garbage collection happens automatically if you cons more than
5901 `gc-cons-threshold' bytes of Lisp data since previous garbage collection.
5902 `garbage-collect' normally returns a list with info on amount of space in use,
5903 where each entry has the form (NAME SIZE USED FREE), where:
5904 - NAME is a symbol describing the kind of objects this entry represents,
5905 - SIZE is the number of bytes used by each one,
5906 - USED is the number of those objects that were found live in the heap,
5907 - FREE is the number of those objects that are not live but that Emacs
5908 keeps around for future allocations (maybe because it does not know how
5909 to return them to the OS).
5910 However, if there was overflow in pure space, `garbage-collect'
5911 returns nil, because real GC can't be done.
5912 See Info node `(elisp)Garbage Collection'. */)
5913 (void)
5915 void *end;
5917 #ifdef HAVE___BUILTIN_UNWIND_INIT
5918 /* Force callee-saved registers and register windows onto the stack.
5919 This is the preferred method if available, obviating the need for
5920 machine dependent methods. */
5921 __builtin_unwind_init ();
5922 end = &end;
5923 #else /* not HAVE___BUILTIN_UNWIND_INIT */
5924 #ifndef GC_SAVE_REGISTERS_ON_STACK
5925 /* jmp_buf may not be aligned enough on darwin-ppc64 */
5926 union aligned_jmpbuf {
5927 Lisp_Object o;
5928 sys_jmp_buf j;
5929 } j;
5930 volatile bool stack_grows_down_p = (char *) &j > (char *) stack_base;
5931 #endif
5932 /* This trick flushes the register windows so that all the state of
5933 the process is contained in the stack. */
5934 /* Fixme: Code in the Boehm GC suggests flushing (with `flushrs') is
5935 needed on ia64 too. See mach_dep.c, where it also says inline
5936 assembler doesn't work with relevant proprietary compilers. */
5937 #ifdef __sparc__
5938 #if defined (__sparc64__) && defined (__FreeBSD__)
5939 /* FreeBSD does not have a ta 3 handler. */
5940 asm ("flushw");
5941 #else
5942 asm ("ta 3");
5943 #endif
5944 #endif
5946 /* Save registers that we need to see on the stack. We need to see
5947 registers used to hold register variables and registers used to
5948 pass parameters. */
5949 #ifdef GC_SAVE_REGISTERS_ON_STACK
5950 GC_SAVE_REGISTERS_ON_STACK (end);
5951 #else /* not GC_SAVE_REGISTERS_ON_STACK */
5953 #ifndef GC_SETJMP_WORKS /* If it hasn't been checked yet that
5954 setjmp will definitely work, test it
5955 and print a message with the result
5956 of the test. */
5957 if (!setjmp_tested_p)
5959 setjmp_tested_p = 1;
5960 test_setjmp ();
5962 #endif /* GC_SETJMP_WORKS */
5964 sys_setjmp (j.j);
5965 end = stack_grows_down_p ? (char *) &j + sizeof j : (char *) &j;
5966 #endif /* not GC_SAVE_REGISTERS_ON_STACK */
5967 #endif /* not HAVE___BUILTIN_UNWIND_INIT */
5968 return garbage_collect_1 (end);
5971 /* Mark Lisp objects in glyph matrix MATRIX. Currently the
5972 only interesting objects referenced from glyphs are strings. */
5974 static void
5975 mark_glyph_matrix (struct glyph_matrix *matrix)
5977 struct glyph_row *row = matrix->rows;
5978 struct glyph_row *end = row + matrix->nrows;
5980 for (; row < end; ++row)
5981 if (row->enabled_p)
5983 int area;
5984 for (area = LEFT_MARGIN_AREA; area < LAST_AREA; ++area)
5986 struct glyph *glyph = row->glyphs[area];
5987 struct glyph *end_glyph = glyph + row->used[area];
5989 for (; glyph < end_glyph; ++glyph)
5990 if (STRINGP (glyph->object)
5991 && !STRING_MARKED_P (XSTRING (glyph->object)))
5992 mark_object (glyph->object);
5997 /* Mark reference to a Lisp_Object.
5998 If the object referred to has not been seen yet, recursively mark
5999 all the references contained in it. */
6001 #define LAST_MARKED_SIZE 500
6002 static Lisp_Object last_marked[LAST_MARKED_SIZE];
6003 static int last_marked_index;
6005 /* For debugging--call abort when we cdr down this many
6006 links of a list, in mark_object. In debugging,
6007 the call to abort will hit a breakpoint.
6008 Normally this is zero and the check never goes off. */
6009 ptrdiff_t mark_object_loop_halt EXTERNALLY_VISIBLE;
6011 static void
6012 mark_vectorlike (struct Lisp_Vector *ptr)
6014 ptrdiff_t size = ptr->header.size;
6015 ptrdiff_t i;
6017 eassert (!VECTOR_MARKED_P (ptr));
6018 VECTOR_MARK (ptr); /* Else mark it. */
6019 if (size & PSEUDOVECTOR_FLAG)
6020 size &= PSEUDOVECTOR_SIZE_MASK;
6022 /* Note that this size is not the memory-footprint size, but only
6023 the number of Lisp_Object fields that we should trace.
6024 The distinction is used e.g. by Lisp_Process which places extra
6025 non-Lisp_Object fields at the end of the structure... */
6026 for (i = 0; i < size; i++) /* ...and then mark its elements. */
6027 mark_object (ptr->contents[i]);
6030 /* Like mark_vectorlike but optimized for char-tables (and
6031 sub-char-tables) assuming that the contents are mostly integers or
6032 symbols. */
6034 static void
6035 mark_char_table (struct Lisp_Vector *ptr, enum pvec_type pvectype)
6037 int size = ptr->header.size & PSEUDOVECTOR_SIZE_MASK;
6038 /* Consult the Lisp_Sub_Char_Table layout before changing this. */
6039 int i, idx = (pvectype == PVEC_SUB_CHAR_TABLE ? SUB_CHAR_TABLE_OFFSET : 0);
6041 eassert (!VECTOR_MARKED_P (ptr));
6042 VECTOR_MARK (ptr);
6043 for (i = idx; i < size; i++)
6045 Lisp_Object val = ptr->contents[i];
6047 if (INTEGERP (val) || (SYMBOLP (val) && XSYMBOL (val)->gcmarkbit))
6048 continue;
6049 if (SUB_CHAR_TABLE_P (val))
6051 if (! VECTOR_MARKED_P (XVECTOR (val)))
6052 mark_char_table (XVECTOR (val), PVEC_SUB_CHAR_TABLE);
6054 else
6055 mark_object (val);
6059 NO_INLINE /* To reduce stack depth in mark_object. */
6060 static Lisp_Object
6061 mark_compiled (struct Lisp_Vector *ptr)
6063 int i, size = ptr->header.size & PSEUDOVECTOR_SIZE_MASK;
6065 VECTOR_MARK (ptr);
6066 for (i = 0; i < size; i++)
6067 if (i != COMPILED_CONSTANTS)
6068 mark_object (ptr->contents[i]);
6069 return size > COMPILED_CONSTANTS ? ptr->contents[COMPILED_CONSTANTS] : Qnil;
6072 /* Mark the chain of overlays starting at PTR. */
6074 static void
6075 mark_overlay (struct Lisp_Overlay *ptr)
6077 for (; ptr && !ptr->gcmarkbit; ptr = ptr->next)
6079 ptr->gcmarkbit = 1;
6080 /* These two are always markers and can be marked fast. */
6081 XMARKER (ptr->start)->gcmarkbit = 1;
6082 XMARKER (ptr->end)->gcmarkbit = 1;
6083 mark_object (ptr->plist);
6087 /* Mark Lisp_Objects and special pointers in BUFFER. */
6089 static void
6090 mark_buffer (struct buffer *buffer)
6092 /* This is handled much like other pseudovectors... */
6093 mark_vectorlike ((struct Lisp_Vector *) buffer);
6095 /* ...but there are some buffer-specific things. */
6097 MARK_INTERVAL_TREE (buffer_intervals (buffer));
6099 /* For now, we just don't mark the undo_list. It's done later in
6100 a special way just before the sweep phase, and after stripping
6101 some of its elements that are not needed any more. */
6103 mark_overlay (buffer->overlays_before);
6104 mark_overlay (buffer->overlays_after);
6106 /* If this is an indirect buffer, mark its base buffer. */
6107 if (buffer->base_buffer && !VECTOR_MARKED_P (buffer->base_buffer))
6108 mark_buffer (buffer->base_buffer);
6111 /* Mark Lisp faces in the face cache C. */
6113 NO_INLINE /* To reduce stack depth in mark_object. */
6114 static void
6115 mark_face_cache (struct face_cache *c)
6117 if (c)
6119 int i, j;
6120 for (i = 0; i < c->used; ++i)
6122 struct face *face = FACE_FROM_ID (c->f, i);
6124 if (face)
6126 if (face->font && !VECTOR_MARKED_P (face->font))
6127 mark_vectorlike ((struct Lisp_Vector *) face->font);
6129 for (j = 0; j < LFACE_VECTOR_SIZE; ++j)
6130 mark_object (face->lface[j]);
6136 NO_INLINE /* To reduce stack depth in mark_object. */
6137 static void
6138 mark_localized_symbol (struct Lisp_Symbol *ptr)
6140 struct Lisp_Buffer_Local_Value *blv = SYMBOL_BLV (ptr);
6141 Lisp_Object where = blv->where;
6142 /* If the value is set up for a killed buffer or deleted
6143 frame, restore its global binding. If the value is
6144 forwarded to a C variable, either it's not a Lisp_Object
6145 var, or it's staticpro'd already. */
6146 if ((BUFFERP (where) && !BUFFER_LIVE_P (XBUFFER (where)))
6147 || (FRAMEP (where) && !FRAME_LIVE_P (XFRAME (where))))
6148 swap_in_global_binding (ptr);
6149 mark_object (blv->where);
6150 mark_object (blv->valcell);
6151 mark_object (blv->defcell);
6154 NO_INLINE /* To reduce stack depth in mark_object. */
6155 static void
6156 mark_save_value (struct Lisp_Save_Value *ptr)
6158 /* If `save_type' is zero, `data[0].pointer' is the address
6159 of a memory area containing `data[1].integer' potential
6160 Lisp_Objects. */
6161 if (ptr->save_type == SAVE_TYPE_MEMORY)
6163 Lisp_Object *p = ptr->data[0].pointer;
6164 ptrdiff_t nelt;
6165 for (nelt = ptr->data[1].integer; nelt > 0; nelt--, p++)
6166 mark_maybe_object (*p);
6168 else
6170 /* Find Lisp_Objects in `data[N]' slots and mark them. */
6171 int i;
6172 for (i = 0; i < SAVE_VALUE_SLOTS; i++)
6173 if (save_type (ptr, i) == SAVE_OBJECT)
6174 mark_object (ptr->data[i].object);
6178 /* Remove killed buffers or items whose car is a killed buffer from
6179 LIST, and mark other items. Return changed LIST, which is marked. */
6181 static Lisp_Object
6182 mark_discard_killed_buffers (Lisp_Object list)
6184 Lisp_Object tail, *prev = &list;
6186 for (tail = list; CONSP (tail) && !CONS_MARKED_P (XCONS (tail));
6187 tail = XCDR (tail))
6189 Lisp_Object tem = XCAR (tail);
6190 if (CONSP (tem))
6191 tem = XCAR (tem);
6192 if (BUFFERP (tem) && !BUFFER_LIVE_P (XBUFFER (tem)))
6193 *prev = XCDR (tail);
6194 else
6196 CONS_MARK (XCONS (tail));
6197 mark_object (XCAR (tail));
6198 prev = xcdr_addr (tail);
6201 mark_object (tail);
6202 return list;
6205 /* Determine type of generic Lisp_Object and mark it accordingly.
6207 This function implements a straightforward depth-first marking
6208 algorithm and so the recursion depth may be very high (a few
6209 tens of thousands is not uncommon). To minimize stack usage,
6210 a few cold paths are moved out to NO_INLINE functions above.
6211 In general, inlining them doesn't help you to gain more speed. */
6213 void
6214 mark_object (Lisp_Object arg)
6216 register Lisp_Object obj;
6217 void *po;
6218 #ifdef GC_CHECK_MARKED_OBJECTS
6219 struct mem_node *m;
6220 #endif
6221 ptrdiff_t cdr_count = 0;
6223 obj = arg;
6224 loop:
6226 po = XPNTR (obj);
6227 if (PURE_P (po))
6228 return;
6230 last_marked[last_marked_index++] = obj;
6231 if (last_marked_index == LAST_MARKED_SIZE)
6232 last_marked_index = 0;
6234 /* Perform some sanity checks on the objects marked here. Abort if
6235 we encounter an object we know is bogus. This increases GC time
6236 by ~80%. */
6237 #ifdef GC_CHECK_MARKED_OBJECTS
6239 /* Check that the object pointed to by PO is known to be a Lisp
6240 structure allocated from the heap. */
6241 #define CHECK_ALLOCATED() \
6242 do { \
6243 m = mem_find (po); \
6244 if (m == MEM_NIL) \
6245 emacs_abort (); \
6246 } while (0)
6248 /* Check that the object pointed to by PO is live, using predicate
6249 function LIVEP. */
6250 #define CHECK_LIVE(LIVEP) \
6251 do { \
6252 if (!LIVEP (m, po)) \
6253 emacs_abort (); \
6254 } while (0)
6256 /* Check both of the above conditions, for non-symbols. */
6257 #define CHECK_ALLOCATED_AND_LIVE(LIVEP) \
6258 do { \
6259 CHECK_ALLOCATED (); \
6260 CHECK_LIVE (LIVEP); \
6261 } while (0) \
6263 /* Check both of the above conditions, for symbols. */
6264 #define CHECK_ALLOCATED_AND_LIVE_SYMBOL() \
6265 do { \
6266 if (!c_symbol_p (ptr)) \
6268 CHECK_ALLOCATED (); \
6269 CHECK_LIVE (live_symbol_p); \
6271 } while (0) \
6273 #else /* not GC_CHECK_MARKED_OBJECTS */
6275 #define CHECK_LIVE(LIVEP) ((void) 0)
6276 #define CHECK_ALLOCATED_AND_LIVE(LIVEP) ((void) 0)
6277 #define CHECK_ALLOCATED_AND_LIVE_SYMBOL() ((void) 0)
6279 #endif /* not GC_CHECK_MARKED_OBJECTS */
6281 switch (XTYPE (obj))
6283 case Lisp_String:
6285 register struct Lisp_String *ptr = XSTRING (obj);
6286 if (STRING_MARKED_P (ptr))
6287 break;
6288 CHECK_ALLOCATED_AND_LIVE (live_string_p);
6289 MARK_STRING (ptr);
6290 MARK_INTERVAL_TREE (ptr->intervals);
6291 #ifdef GC_CHECK_STRING_BYTES
6292 /* Check that the string size recorded in the string is the
6293 same as the one recorded in the sdata structure. */
6294 string_bytes (ptr);
6295 #endif /* GC_CHECK_STRING_BYTES */
6297 break;
6299 case Lisp_Vectorlike:
6301 register struct Lisp_Vector *ptr = XVECTOR (obj);
6302 register ptrdiff_t pvectype;
6304 if (VECTOR_MARKED_P (ptr))
6305 break;
6307 #ifdef GC_CHECK_MARKED_OBJECTS
6308 m = mem_find (po);
6309 if (m == MEM_NIL && !SUBRP (obj))
6310 emacs_abort ();
6311 #endif /* GC_CHECK_MARKED_OBJECTS */
6313 if (ptr->header.size & PSEUDOVECTOR_FLAG)
6314 pvectype = ((ptr->header.size & PVEC_TYPE_MASK)
6315 >> PSEUDOVECTOR_AREA_BITS);
6316 else
6317 pvectype = PVEC_NORMAL_VECTOR;
6319 if (pvectype != PVEC_SUBR && pvectype != PVEC_BUFFER)
6320 CHECK_LIVE (live_vector_p);
6322 switch (pvectype)
6324 case PVEC_BUFFER:
6325 #ifdef GC_CHECK_MARKED_OBJECTS
6327 struct buffer *b;
6328 FOR_EACH_BUFFER (b)
6329 if (b == po)
6330 break;
6331 if (b == NULL)
6332 emacs_abort ();
6334 #endif /* GC_CHECK_MARKED_OBJECTS */
6335 mark_buffer ((struct buffer *) ptr);
6336 break;
6338 case PVEC_COMPILED:
6339 /* Although we could treat this just like a vector, mark_compiled
6340 returns the COMPILED_CONSTANTS element, which is marked at the
6341 next iteration of goto-loop here. This is done to avoid a few
6342 recursive calls to mark_object. */
6343 obj = mark_compiled (ptr);
6344 if (!NILP (obj))
6345 goto loop;
6346 break;
6348 case PVEC_FRAME:
6350 struct frame *f = (struct frame *) ptr;
6352 mark_vectorlike (ptr);
6353 mark_face_cache (f->face_cache);
6354 #ifdef HAVE_WINDOW_SYSTEM
6355 if (FRAME_WINDOW_P (f) && FRAME_X_OUTPUT (f))
6357 struct font *font = FRAME_FONT (f);
6359 if (font && !VECTOR_MARKED_P (font))
6360 mark_vectorlike ((struct Lisp_Vector *) font);
6362 #endif
6364 break;
6366 case PVEC_WINDOW:
6368 struct window *w = (struct window *) ptr;
6370 mark_vectorlike (ptr);
6372 /* Mark glyph matrices, if any. Marking window
6373 matrices is sufficient because frame matrices
6374 use the same glyph memory. */
6375 if (w->current_matrix)
6377 mark_glyph_matrix (w->current_matrix);
6378 mark_glyph_matrix (w->desired_matrix);
6381 /* Filter out killed buffers from both buffer lists
6382 in attempt to help GC to reclaim killed buffers faster.
6383 We can do it elsewhere for live windows, but this is the
6384 best place to do it for dead windows. */
6385 wset_prev_buffers
6386 (w, mark_discard_killed_buffers (w->prev_buffers));
6387 wset_next_buffers
6388 (w, mark_discard_killed_buffers (w->next_buffers));
6390 break;
6392 case PVEC_HASH_TABLE:
6394 struct Lisp_Hash_Table *h = (struct Lisp_Hash_Table *) ptr;
6396 mark_vectorlike (ptr);
6397 mark_object (h->test.name);
6398 mark_object (h->test.user_hash_function);
6399 mark_object (h->test.user_cmp_function);
6400 /* If hash table is not weak, mark all keys and values.
6401 For weak tables, mark only the vector. */
6402 if (NILP (h->weak))
6403 mark_object (h->key_and_value);
6404 else
6405 VECTOR_MARK (XVECTOR (h->key_and_value));
6407 break;
6409 case PVEC_CHAR_TABLE:
6410 case PVEC_SUB_CHAR_TABLE:
6411 mark_char_table (ptr, (enum pvec_type) pvectype);
6412 break;
6414 case PVEC_BOOL_VECTOR:
6415 /* No Lisp_Objects to mark in a bool vector. */
6416 VECTOR_MARK (ptr);
6417 break;
6419 case PVEC_SUBR:
6420 break;
6422 case PVEC_FREE:
6423 emacs_abort ();
6425 default:
6426 mark_vectorlike (ptr);
6429 break;
6431 case Lisp_Symbol:
6433 register struct Lisp_Symbol *ptr = XSYMBOL (obj);
6434 nextsym:
6435 if (ptr->gcmarkbit)
6436 break;
6437 CHECK_ALLOCATED_AND_LIVE_SYMBOL ();
6438 ptr->gcmarkbit = 1;
6439 /* Attempt to catch bogus objects. */
6440 eassert (valid_lisp_object_p (ptr->function));
6441 mark_object (ptr->function);
6442 mark_object (ptr->plist);
6443 switch (ptr->redirect)
6445 case SYMBOL_PLAINVAL: mark_object (SYMBOL_VAL (ptr)); break;
6446 case SYMBOL_VARALIAS:
6448 Lisp_Object tem;
6449 XSETSYMBOL (tem, SYMBOL_ALIAS (ptr));
6450 mark_object (tem);
6451 break;
6453 case SYMBOL_LOCALIZED:
6454 mark_localized_symbol (ptr);
6455 break;
6456 case SYMBOL_FORWARDED:
6457 /* If the value is forwarded to a buffer or keyboard field,
6458 these are marked when we see the corresponding object.
6459 And if it's forwarded to a C variable, either it's not
6460 a Lisp_Object var, or it's staticpro'd already. */
6461 break;
6462 default: emacs_abort ();
6464 if (!PURE_P (XSTRING (ptr->name)))
6465 MARK_STRING (XSTRING (ptr->name));
6466 MARK_INTERVAL_TREE (string_intervals (ptr->name));
6467 /* Inner loop to mark next symbol in this bucket, if any. */
6468 po = ptr = ptr->next;
6469 if (ptr)
6470 goto nextsym;
6472 break;
6474 case Lisp_Misc:
6475 CHECK_ALLOCATED_AND_LIVE (live_misc_p);
6477 if (XMISCANY (obj)->gcmarkbit)
6478 break;
6480 switch (XMISCTYPE (obj))
6482 case Lisp_Misc_Marker:
6483 /* DO NOT mark thru the marker's chain.
6484 The buffer's markers chain does not preserve markers from gc;
6485 instead, markers are removed from the chain when freed by gc. */
6486 XMISCANY (obj)->gcmarkbit = 1;
6487 break;
6489 case Lisp_Misc_Save_Value:
6490 XMISCANY (obj)->gcmarkbit = 1;
6491 mark_save_value (XSAVE_VALUE (obj));
6492 break;
6494 case Lisp_Misc_Overlay:
6495 mark_overlay (XOVERLAY (obj));
6496 break;
6498 case Lisp_Misc_Finalizer:
6499 XMISCANY (obj)->gcmarkbit = true;
6500 mark_object (XFINALIZER (obj)->function);
6501 break;
6503 #ifdef HAVE_MODULES
6504 case Lisp_Misc_User_Ptr:
6505 XMISCANY (obj)->gcmarkbit = true;
6506 break;
6507 #endif
6509 default:
6510 emacs_abort ();
6512 break;
6514 case Lisp_Cons:
6516 register struct Lisp_Cons *ptr = XCONS (obj);
6517 if (CONS_MARKED_P (ptr))
6518 break;
6519 CHECK_ALLOCATED_AND_LIVE (live_cons_p);
6520 CONS_MARK (ptr);
6521 /* If the cdr is nil, avoid recursion for the car. */
6522 if (EQ (ptr->u.cdr, Qnil))
6524 obj = ptr->car;
6525 cdr_count = 0;
6526 goto loop;
6528 mark_object (ptr->car);
6529 obj = ptr->u.cdr;
6530 cdr_count++;
6531 if (cdr_count == mark_object_loop_halt)
6532 emacs_abort ();
6533 goto loop;
6536 case Lisp_Float:
6537 CHECK_ALLOCATED_AND_LIVE (live_float_p);
6538 FLOAT_MARK (XFLOAT (obj));
6539 break;
6541 case_Lisp_Int:
6542 break;
6544 default:
6545 emacs_abort ();
6548 #undef CHECK_LIVE
6549 #undef CHECK_ALLOCATED
6550 #undef CHECK_ALLOCATED_AND_LIVE
6552 /* Mark the Lisp pointers in the terminal objects.
6553 Called by Fgarbage_collect. */
6555 static void
6556 mark_terminals (void)
6558 struct terminal *t;
6559 for (t = terminal_list; t; t = t->next_terminal)
6561 eassert (t->name != NULL);
6562 #ifdef HAVE_WINDOW_SYSTEM
6563 /* If a terminal object is reachable from a stacpro'ed object,
6564 it might have been marked already. Make sure the image cache
6565 gets marked. */
6566 mark_image_cache (t->image_cache);
6567 #endif /* HAVE_WINDOW_SYSTEM */
6568 if (!VECTOR_MARKED_P (t))
6569 mark_vectorlike ((struct Lisp_Vector *)t);
6575 /* Value is non-zero if OBJ will survive the current GC because it's
6576 either marked or does not need to be marked to survive. */
6578 bool
6579 survives_gc_p (Lisp_Object obj)
6581 bool survives_p;
6583 switch (XTYPE (obj))
6585 case_Lisp_Int:
6586 survives_p = 1;
6587 break;
6589 case Lisp_Symbol:
6590 survives_p = XSYMBOL (obj)->gcmarkbit;
6591 break;
6593 case Lisp_Misc:
6594 survives_p = XMISCANY (obj)->gcmarkbit;
6595 break;
6597 case Lisp_String:
6598 survives_p = STRING_MARKED_P (XSTRING (obj));
6599 break;
6601 case Lisp_Vectorlike:
6602 survives_p = SUBRP (obj) || VECTOR_MARKED_P (XVECTOR (obj));
6603 break;
6605 case Lisp_Cons:
6606 survives_p = CONS_MARKED_P (XCONS (obj));
6607 break;
6609 case Lisp_Float:
6610 survives_p = FLOAT_MARKED_P (XFLOAT (obj));
6611 break;
6613 default:
6614 emacs_abort ();
6617 return survives_p || PURE_P (XPNTR (obj));
6623 NO_INLINE /* For better stack traces */
6624 static void
6625 sweep_conses (void)
6627 struct cons_block *cblk;
6628 struct cons_block **cprev = &cons_block;
6629 int lim = cons_block_index;
6630 EMACS_INT num_free = 0, num_used = 0;
6632 cons_free_list = 0;
6634 for (cblk = cons_block; cblk; cblk = *cprev)
6636 int i = 0;
6637 int this_free = 0;
6638 int ilim = (lim + BITS_PER_BITS_WORD - 1) / BITS_PER_BITS_WORD;
6640 /* Scan the mark bits an int at a time. */
6641 for (i = 0; i < ilim; i++)
6643 if (cblk->gcmarkbits[i] == BITS_WORD_MAX)
6645 /* Fast path - all cons cells for this int are marked. */
6646 cblk->gcmarkbits[i] = 0;
6647 num_used += BITS_PER_BITS_WORD;
6649 else
6651 /* Some cons cells for this int are not marked.
6652 Find which ones, and free them. */
6653 int start, pos, stop;
6655 start = i * BITS_PER_BITS_WORD;
6656 stop = lim - start;
6657 if (stop > BITS_PER_BITS_WORD)
6658 stop = BITS_PER_BITS_WORD;
6659 stop += start;
6661 for (pos = start; pos < stop; pos++)
6663 if (!CONS_MARKED_P (&cblk->conses[pos]))
6665 this_free++;
6666 cblk->conses[pos].u.chain = cons_free_list;
6667 cons_free_list = &cblk->conses[pos];
6668 cons_free_list->car = Vdead;
6670 else
6672 num_used++;
6673 CONS_UNMARK (&cblk->conses[pos]);
6679 lim = CONS_BLOCK_SIZE;
6680 /* If this block contains only free conses and we have already
6681 seen more than two blocks worth of free conses then deallocate
6682 this block. */
6683 if (this_free == CONS_BLOCK_SIZE && num_free > CONS_BLOCK_SIZE)
6685 *cprev = cblk->next;
6686 /* Unhook from the free list. */
6687 cons_free_list = cblk->conses[0].u.chain;
6688 lisp_align_free (cblk);
6690 else
6692 num_free += this_free;
6693 cprev = &cblk->next;
6696 total_conses = num_used;
6697 total_free_conses = num_free;
6700 NO_INLINE /* For better stack traces */
6701 static void
6702 sweep_floats (void)
6704 register struct float_block *fblk;
6705 struct float_block **fprev = &float_block;
6706 register int lim = float_block_index;
6707 EMACS_INT num_free = 0, num_used = 0;
6709 float_free_list = 0;
6711 for (fblk = float_block; fblk; fblk = *fprev)
6713 register int i;
6714 int this_free = 0;
6715 for (i = 0; i < lim; i++)
6716 if (!FLOAT_MARKED_P (&fblk->floats[i]))
6718 this_free++;
6719 fblk->floats[i].u.chain = float_free_list;
6720 float_free_list = &fblk->floats[i];
6722 else
6724 num_used++;
6725 FLOAT_UNMARK (&fblk->floats[i]);
6727 lim = FLOAT_BLOCK_SIZE;
6728 /* If this block contains only free floats and we have already
6729 seen more than two blocks worth of free floats then deallocate
6730 this block. */
6731 if (this_free == FLOAT_BLOCK_SIZE && num_free > FLOAT_BLOCK_SIZE)
6733 *fprev = fblk->next;
6734 /* Unhook from the free list. */
6735 float_free_list = fblk->floats[0].u.chain;
6736 lisp_align_free (fblk);
6738 else
6740 num_free += this_free;
6741 fprev = &fblk->next;
6744 total_floats = num_used;
6745 total_free_floats = num_free;
6748 NO_INLINE /* For better stack traces */
6749 static void
6750 sweep_intervals (void)
6752 register struct interval_block *iblk;
6753 struct interval_block **iprev = &interval_block;
6754 register int lim = interval_block_index;
6755 EMACS_INT num_free = 0, num_used = 0;
6757 interval_free_list = 0;
6759 for (iblk = interval_block; iblk; iblk = *iprev)
6761 register int i;
6762 int this_free = 0;
6764 for (i = 0; i < lim; i++)
6766 if (!iblk->intervals[i].gcmarkbit)
6768 set_interval_parent (&iblk->intervals[i], interval_free_list);
6769 interval_free_list = &iblk->intervals[i];
6770 this_free++;
6772 else
6774 num_used++;
6775 iblk->intervals[i].gcmarkbit = 0;
6778 lim = INTERVAL_BLOCK_SIZE;
6779 /* If this block contains only free intervals and we have already
6780 seen more than two blocks worth of free intervals then
6781 deallocate this block. */
6782 if (this_free == INTERVAL_BLOCK_SIZE && num_free > INTERVAL_BLOCK_SIZE)
6784 *iprev = iblk->next;
6785 /* Unhook from the free list. */
6786 interval_free_list = INTERVAL_PARENT (&iblk->intervals[0]);
6787 lisp_free (iblk);
6789 else
6791 num_free += this_free;
6792 iprev = &iblk->next;
6795 total_intervals = num_used;
6796 total_free_intervals = num_free;
6799 NO_INLINE /* For better stack traces */
6800 static void
6801 sweep_symbols (void)
6803 struct symbol_block *sblk;
6804 struct symbol_block **sprev = &symbol_block;
6805 int lim = symbol_block_index;
6806 EMACS_INT num_free = 0, num_used = ARRAYELTS (lispsym);
6808 symbol_free_list = NULL;
6810 for (int i = 0; i < ARRAYELTS (lispsym); i++)
6811 lispsym[i].gcmarkbit = 0;
6813 for (sblk = symbol_block; sblk; sblk = *sprev)
6815 int this_free = 0;
6816 union aligned_Lisp_Symbol *sym = sblk->symbols;
6817 union aligned_Lisp_Symbol *end = sym + lim;
6819 for (; sym < end; ++sym)
6821 if (!sym->s.gcmarkbit)
6823 if (sym->s.redirect == SYMBOL_LOCALIZED)
6824 xfree (SYMBOL_BLV (&sym->s));
6825 sym->s.next = symbol_free_list;
6826 symbol_free_list = &sym->s;
6827 symbol_free_list->function = Vdead;
6828 ++this_free;
6830 else
6832 ++num_used;
6833 sym->s.gcmarkbit = 0;
6834 /* Attempt to catch bogus objects. */
6835 eassert (valid_lisp_object_p (sym->s.function));
6839 lim = SYMBOL_BLOCK_SIZE;
6840 /* If this block contains only free symbols and we have already
6841 seen more than two blocks worth of free symbols then deallocate
6842 this block. */
6843 if (this_free == SYMBOL_BLOCK_SIZE && num_free > SYMBOL_BLOCK_SIZE)
6845 *sprev = sblk->next;
6846 /* Unhook from the free list. */
6847 symbol_free_list = sblk->symbols[0].s.next;
6848 lisp_free (sblk);
6850 else
6852 num_free += this_free;
6853 sprev = &sblk->next;
6856 total_symbols = num_used;
6857 total_free_symbols = num_free;
6860 NO_INLINE /* For better stack traces. */
6861 static void
6862 sweep_misc (void)
6864 register struct marker_block *mblk;
6865 struct marker_block **mprev = &marker_block;
6866 register int lim = marker_block_index;
6867 EMACS_INT num_free = 0, num_used = 0;
6869 /* Put all unmarked misc's on free list. For a marker, first
6870 unchain it from the buffer it points into. */
6872 marker_free_list = 0;
6874 for (mblk = marker_block; mblk; mblk = *mprev)
6876 register int i;
6877 int this_free = 0;
6879 for (i = 0; i < lim; i++)
6881 if (!mblk->markers[i].m.u_any.gcmarkbit)
6883 if (mblk->markers[i].m.u_any.type == Lisp_Misc_Marker)
6884 unchain_marker (&mblk->markers[i].m.u_marker);
6885 else if (mblk->markers[i].m.u_any.type == Lisp_Misc_Finalizer)
6886 unchain_finalizer (&mblk->markers[i].m.u_finalizer);
6887 #ifdef HAVE_MODULES
6888 else if (mblk->markers[i].m.u_any.type == Lisp_Misc_User_Ptr)
6890 struct Lisp_User_Ptr *uptr = &mblk->markers[i].m.u_user_ptr;
6891 uptr->finalizer (uptr->p);
6893 #endif
6894 /* Set the type of the freed object to Lisp_Misc_Free.
6895 We could leave the type alone, since nobody checks it,
6896 but this might catch bugs faster. */
6897 mblk->markers[i].m.u_marker.type = Lisp_Misc_Free;
6898 mblk->markers[i].m.u_free.chain = marker_free_list;
6899 marker_free_list = &mblk->markers[i].m;
6900 this_free++;
6902 else
6904 num_used++;
6905 mblk->markers[i].m.u_any.gcmarkbit = 0;
6908 lim = MARKER_BLOCK_SIZE;
6909 /* If this block contains only free markers and we have already
6910 seen more than two blocks worth of free markers then deallocate
6911 this block. */
6912 if (this_free == MARKER_BLOCK_SIZE && num_free > MARKER_BLOCK_SIZE)
6914 *mprev = mblk->next;
6915 /* Unhook from the free list. */
6916 marker_free_list = mblk->markers[0].m.u_free.chain;
6917 lisp_free (mblk);
6919 else
6921 num_free += this_free;
6922 mprev = &mblk->next;
6926 total_markers = num_used;
6927 total_free_markers = num_free;
6930 NO_INLINE /* For better stack traces */
6931 static void
6932 sweep_buffers (void)
6934 register struct buffer *buffer, **bprev = &all_buffers;
6936 total_buffers = 0;
6937 for (buffer = all_buffers; buffer; buffer = *bprev)
6938 if (!VECTOR_MARKED_P (buffer))
6940 *bprev = buffer->next;
6941 lisp_free (buffer);
6943 else
6945 VECTOR_UNMARK (buffer);
6946 /* Do not use buffer_(set|get)_intervals here. */
6947 buffer->text->intervals = balance_intervals (buffer->text->intervals);
6948 total_buffers++;
6949 bprev = &buffer->next;
6953 /* Sweep: find all structures not marked, and free them. */
6954 static void
6955 gc_sweep (void)
6957 /* Remove or mark entries in weak hash tables.
6958 This must be done before any object is unmarked. */
6959 sweep_weak_hash_tables ();
6961 sweep_strings ();
6962 check_string_bytes (!noninteractive);
6963 sweep_conses ();
6964 sweep_floats ();
6965 sweep_intervals ();
6966 sweep_symbols ();
6967 sweep_misc ();
6968 sweep_buffers ();
6969 sweep_vectors ();
6970 check_string_bytes (!noninteractive);
6973 DEFUN ("memory-info", Fmemory_info, Smemory_info, 0, 0, 0,
6974 doc: /* Return a list of (TOTAL-RAM FREE-RAM TOTAL-SWAP FREE-SWAP).
6975 All values are in Kbytes. If there is no swap space,
6976 last two values are zero. If the system is not supported
6977 or memory information can't be obtained, return nil. */)
6978 (void)
6980 #if defined HAVE_LINUX_SYSINFO
6981 struct sysinfo si;
6982 uintmax_t units;
6984 if (sysinfo (&si))
6985 return Qnil;
6986 #ifdef LINUX_SYSINFO_UNIT
6987 units = si.mem_unit;
6988 #else
6989 units = 1;
6990 #endif
6991 return list4i ((uintmax_t) si.totalram * units / 1024,
6992 (uintmax_t) si.freeram * units / 1024,
6993 (uintmax_t) si.totalswap * units / 1024,
6994 (uintmax_t) si.freeswap * units / 1024);
6995 #elif defined WINDOWSNT
6996 unsigned long long totalram, freeram, totalswap, freeswap;
6998 if (w32_memory_info (&totalram, &freeram, &totalswap, &freeswap) == 0)
6999 return list4i ((uintmax_t) totalram / 1024,
7000 (uintmax_t) freeram / 1024,
7001 (uintmax_t) totalswap / 1024,
7002 (uintmax_t) freeswap / 1024);
7003 else
7004 return Qnil;
7005 #elif defined MSDOS
7006 unsigned long totalram, freeram, totalswap, freeswap;
7008 if (dos_memory_info (&totalram, &freeram, &totalswap, &freeswap) == 0)
7009 return list4i ((uintmax_t) totalram / 1024,
7010 (uintmax_t) freeram / 1024,
7011 (uintmax_t) totalswap / 1024,
7012 (uintmax_t) freeswap / 1024);
7013 else
7014 return Qnil;
7015 #else /* not HAVE_LINUX_SYSINFO, not WINDOWSNT, not MSDOS */
7016 /* FIXME: add more systems. */
7017 return Qnil;
7018 #endif /* HAVE_LINUX_SYSINFO, not WINDOWSNT, not MSDOS */
7021 /* Debugging aids. */
7023 DEFUN ("memory-limit", Fmemory_limit, Smemory_limit, 0, 0, 0,
7024 doc: /* Return the address of the last byte Emacs has allocated, divided by 1024.
7025 This may be helpful in debugging Emacs's memory usage.
7026 We divide the value by 1024 to make sure it fits in a Lisp integer. */)
7027 (void)
7029 Lisp_Object end;
7031 #ifdef HAVE_NS
7032 /* Avoid warning. sbrk has no relation to memory allocated anyway. */
7033 XSETINT (end, 0);
7034 #else
7035 XSETINT (end, (intptr_t) (char *) sbrk (0) / 1024);
7036 #endif
7038 return end;
7041 DEFUN ("memory-use-counts", Fmemory_use_counts, Smemory_use_counts, 0, 0, 0,
7042 doc: /* Return a list of counters that measure how much consing there has been.
7043 Each of these counters increments for a certain kind of object.
7044 The counters wrap around from the largest positive integer to zero.
7045 Garbage collection does not decrease them.
7046 The elements of the value are as follows:
7047 (CONSES FLOATS VECTOR-CELLS SYMBOLS STRING-CHARS MISCS INTERVALS STRINGS)
7048 All are in units of 1 = one object consed
7049 except for VECTOR-CELLS and STRING-CHARS, which count the total length of
7050 objects consed.
7051 MISCS include overlays, markers, and some internal types.
7052 Frames, windows, buffers, and subprocesses count as vectors
7053 (but the contents of a buffer's text do not count here). */)
7054 (void)
7056 return listn (CONSTYPE_HEAP, 8,
7057 bounded_number (cons_cells_consed),
7058 bounded_number (floats_consed),
7059 bounded_number (vector_cells_consed),
7060 bounded_number (symbols_consed),
7061 bounded_number (string_chars_consed),
7062 bounded_number (misc_objects_consed),
7063 bounded_number (intervals_consed),
7064 bounded_number (strings_consed));
7067 static bool
7068 symbol_uses_obj (Lisp_Object symbol, Lisp_Object obj)
7070 struct Lisp_Symbol *sym = XSYMBOL (symbol);
7071 Lisp_Object val = find_symbol_value (symbol);
7072 return (EQ (val, obj)
7073 || EQ (sym->function, obj)
7074 || (!NILP (sym->function)
7075 && COMPILEDP (sym->function)
7076 && EQ (AREF (sym->function, COMPILED_BYTECODE), obj))
7077 || (!NILP (val)
7078 && COMPILEDP (val)
7079 && EQ (AREF (val, COMPILED_BYTECODE), obj)));
7082 /* Find at most FIND_MAX symbols which have OBJ as their value or
7083 function. This is used in gdbinit's `xwhichsymbols' command. */
7085 Lisp_Object
7086 which_symbols (Lisp_Object obj, EMACS_INT find_max)
7088 struct symbol_block *sblk;
7089 ptrdiff_t gc_count = inhibit_garbage_collection ();
7090 Lisp_Object found = Qnil;
7092 if (! DEADP (obj))
7094 for (int i = 0; i < ARRAYELTS (lispsym); i++)
7096 Lisp_Object sym = builtin_lisp_symbol (i);
7097 if (symbol_uses_obj (sym, obj))
7099 found = Fcons (sym, found);
7100 if (--find_max == 0)
7101 goto out;
7105 for (sblk = symbol_block; sblk; sblk = sblk->next)
7107 union aligned_Lisp_Symbol *aligned_sym = sblk->symbols;
7108 int bn;
7110 for (bn = 0; bn < SYMBOL_BLOCK_SIZE; bn++, aligned_sym++)
7112 if (sblk == symbol_block && bn >= symbol_block_index)
7113 break;
7115 Lisp_Object sym = make_lisp_symbol (&aligned_sym->s);
7116 if (symbol_uses_obj (sym, obj))
7118 found = Fcons (sym, found);
7119 if (--find_max == 0)
7120 goto out;
7126 out:
7127 unbind_to (gc_count, Qnil);
7128 return found;
7131 #ifdef SUSPICIOUS_OBJECT_CHECKING
7133 static void *
7134 find_suspicious_object_in_range (void *begin, void *end)
7136 char *begin_a = begin;
7137 char *end_a = end;
7138 int i;
7140 for (i = 0; i < ARRAYELTS (suspicious_objects); ++i)
7142 char *suspicious_object = suspicious_objects[i];
7143 if (begin_a <= suspicious_object && suspicious_object < end_a)
7144 return suspicious_object;
7147 return NULL;
7150 static void
7151 note_suspicious_free (void* ptr)
7153 struct suspicious_free_record* rec;
7155 rec = &suspicious_free_history[suspicious_free_history_index++];
7156 if (suspicious_free_history_index ==
7157 ARRAYELTS (suspicious_free_history))
7159 suspicious_free_history_index = 0;
7162 memset (rec, 0, sizeof (*rec));
7163 rec->suspicious_object = ptr;
7164 backtrace (&rec->backtrace[0], ARRAYELTS (rec->backtrace));
7167 static void
7168 detect_suspicious_free (void* ptr)
7170 int i;
7172 eassert (ptr != NULL);
7174 for (i = 0; i < ARRAYELTS (suspicious_objects); ++i)
7175 if (suspicious_objects[i] == ptr)
7177 note_suspicious_free (ptr);
7178 suspicious_objects[i] = NULL;
7182 #endif /* SUSPICIOUS_OBJECT_CHECKING */
7184 DEFUN ("suspicious-object", Fsuspicious_object, Ssuspicious_object, 1, 1, 0,
7185 doc: /* Return OBJ, maybe marking it for extra scrutiny.
7186 If Emacs is compiled with suspicious object checking, capture
7187 a stack trace when OBJ is freed in order to help track down
7188 garbage collection bugs. Otherwise, do nothing and return OBJ. */)
7189 (Lisp_Object obj)
7191 #ifdef SUSPICIOUS_OBJECT_CHECKING
7192 /* Right now, we care only about vectors. */
7193 if (VECTORLIKEP (obj))
7195 suspicious_objects[suspicious_object_index++] = XVECTOR (obj);
7196 if (suspicious_object_index == ARRAYELTS (suspicious_objects))
7197 suspicious_object_index = 0;
7199 #endif
7200 return obj;
7203 #ifdef ENABLE_CHECKING
7205 bool suppress_checking;
7207 void
7208 die (const char *msg, const char *file, int line)
7210 fprintf (stderr, "\r\n%s:%d: Emacs fatal error: assertion failed: %s\r\n",
7211 file, line, msg);
7212 terminate_due_to_signal (SIGABRT, INT_MAX);
7215 #endif /* ENABLE_CHECKING */
7217 #if defined (ENABLE_CHECKING) && USE_STACK_LISP_OBJECTS
7219 /* Stress alloca with inconveniently sized requests and check
7220 whether all allocated areas may be used for Lisp_Object. */
7222 NO_INLINE static void
7223 verify_alloca (void)
7225 int i;
7226 enum { ALLOCA_CHECK_MAX = 256 };
7227 /* Start from size of the smallest Lisp object. */
7228 for (i = sizeof (struct Lisp_Cons); i <= ALLOCA_CHECK_MAX; i++)
7230 void *ptr = alloca (i);
7231 make_lisp_ptr (ptr, Lisp_Cons);
7235 #else /* not ENABLE_CHECKING && USE_STACK_LISP_OBJECTS */
7237 #define verify_alloca() ((void) 0)
7239 #endif /* ENABLE_CHECKING && USE_STACK_LISP_OBJECTS */
7241 /* Initialization. */
7243 void
7244 init_alloc_once (void)
7246 /* Even though Qt's contents are not set up, its address is known. */
7247 Vpurify_flag = Qt;
7249 purebeg = PUREBEG;
7250 pure_size = PURESIZE;
7252 verify_alloca ();
7253 init_finalizer_list (&finalizers);
7254 init_finalizer_list (&doomed_finalizers);
7256 mem_init ();
7257 Vdead = make_pure_string ("DEAD", 4, 4, 0);
7259 #ifdef DOUG_LEA_MALLOC
7260 mallopt (M_TRIM_THRESHOLD, 128 * 1024); /* Trim threshold. */
7261 mallopt (M_MMAP_THRESHOLD, 64 * 1024); /* Mmap threshold. */
7262 mallopt (M_MMAP_MAX, MMAP_MAX_AREAS); /* Max. number of mmap'ed areas. */
7263 #endif
7264 init_strings ();
7265 init_vectors ();
7267 refill_memory_reserve ();
7268 gc_cons_threshold = GC_DEFAULT_THRESHOLD;
7271 void
7272 init_alloc (void)
7274 #if !defined GC_SAVE_REGISTERS_ON_STACK && !defined GC_SETJMP_WORKS
7275 setjmp_tested_p = longjmps_done = 0;
7276 #endif
7277 Vgc_elapsed = make_float (0.0);
7278 gcs_done = 0;
7280 #if USE_VALGRIND
7281 valgrind_p = RUNNING_ON_VALGRIND != 0;
7282 #endif
7285 void
7286 syms_of_alloc (void)
7288 DEFVAR_INT ("gc-cons-threshold", gc_cons_threshold,
7289 doc: /* Number of bytes of consing between garbage collections.
7290 Garbage collection can happen automatically once this many bytes have been
7291 allocated since the last garbage collection. All data types count.
7293 Garbage collection happens automatically only when `eval' is called.
7295 By binding this temporarily to a large number, you can effectively
7296 prevent garbage collection during a part of the program.
7297 See also `gc-cons-percentage'. */);
7299 DEFVAR_LISP ("gc-cons-percentage", Vgc_cons_percentage,
7300 doc: /* Portion of the heap used for allocation.
7301 Garbage collection can happen automatically once this portion of the heap
7302 has been allocated since the last garbage collection.
7303 If this portion is smaller than `gc-cons-threshold', this is ignored. */);
7304 Vgc_cons_percentage = make_float (0.1);
7306 DEFVAR_INT ("pure-bytes-used", pure_bytes_used,
7307 doc: /* Number of bytes of shareable Lisp data allocated so far. */);
7309 DEFVAR_INT ("cons-cells-consed", cons_cells_consed,
7310 doc: /* Number of cons cells that have been consed so far. */);
7312 DEFVAR_INT ("floats-consed", floats_consed,
7313 doc: /* Number of floats that have been consed so far. */);
7315 DEFVAR_INT ("vector-cells-consed", vector_cells_consed,
7316 doc: /* Number of vector cells that have been consed so far. */);
7318 DEFVAR_INT ("symbols-consed", symbols_consed,
7319 doc: /* Number of symbols that have been consed so far. */);
7320 symbols_consed += ARRAYELTS (lispsym);
7322 DEFVAR_INT ("string-chars-consed", string_chars_consed,
7323 doc: /* Number of string characters that have been consed so far. */);
7325 DEFVAR_INT ("misc-objects-consed", misc_objects_consed,
7326 doc: /* Number of miscellaneous objects that have been consed so far.
7327 These include markers and overlays, plus certain objects not visible
7328 to users. */);
7330 DEFVAR_INT ("intervals-consed", intervals_consed,
7331 doc: /* Number of intervals that have been consed so far. */);
7333 DEFVAR_INT ("strings-consed", strings_consed,
7334 doc: /* Number of strings that have been consed so far. */);
7336 DEFVAR_LISP ("purify-flag", Vpurify_flag,
7337 doc: /* Non-nil means loading Lisp code in order to dump an executable.
7338 This means that certain objects should be allocated in shared (pure) space.
7339 It can also be set to a hash-table, in which case this table is used to
7340 do hash-consing of the objects allocated to pure space. */);
7342 DEFVAR_BOOL ("garbage-collection-messages", garbage_collection_messages,
7343 doc: /* Non-nil means display messages at start and end of garbage collection. */);
7344 garbage_collection_messages = 0;
7346 DEFVAR_LISP ("post-gc-hook", Vpost_gc_hook,
7347 doc: /* Hook run after garbage collection has finished. */);
7348 Vpost_gc_hook = Qnil;
7349 DEFSYM (Qpost_gc_hook, "post-gc-hook");
7351 DEFVAR_LISP ("memory-signal-data", Vmemory_signal_data,
7352 doc: /* Precomputed `signal' argument for memory-full error. */);
7353 /* We build this in advance because if we wait until we need it, we might
7354 not be able to allocate the memory to hold it. */
7355 Vmemory_signal_data
7356 = listn (CONSTYPE_PURE, 2, Qerror,
7357 build_pure_c_string ("Memory exhausted--use M-x save-some-buffers then exit and restart Emacs"));
7359 DEFVAR_LISP ("memory-full", Vmemory_full,
7360 doc: /* Non-nil means Emacs cannot get much more Lisp memory. */);
7361 Vmemory_full = Qnil;
7363 DEFSYM (Qconses, "conses");
7364 DEFSYM (Qsymbols, "symbols");
7365 DEFSYM (Qmiscs, "miscs");
7366 DEFSYM (Qstrings, "strings");
7367 DEFSYM (Qvectors, "vectors");
7368 DEFSYM (Qfloats, "floats");
7369 DEFSYM (Qintervals, "intervals");
7370 DEFSYM (Qbuffers, "buffers");
7371 DEFSYM (Qstring_bytes, "string-bytes");
7372 DEFSYM (Qvector_slots, "vector-slots");
7373 DEFSYM (Qheap, "heap");
7374 DEFSYM (QAutomatic_GC, "Automatic GC");
7376 DEFSYM (Qgc_cons_threshold, "gc-cons-threshold");
7377 DEFSYM (Qchar_table_extra_slots, "char-table-extra-slots");
7379 DEFVAR_LISP ("gc-elapsed", Vgc_elapsed,
7380 doc: /* Accumulated time elapsed in garbage collections.
7381 The time is in seconds as a floating point value. */);
7382 DEFVAR_INT ("gcs-done", gcs_done,
7383 doc: /* Accumulated number of garbage collections done. */);
7385 defsubr (&Scons);
7386 defsubr (&Slist);
7387 defsubr (&Svector);
7388 defsubr (&Sbool_vector);
7389 defsubr (&Smake_byte_code);
7390 defsubr (&Smake_list);
7391 defsubr (&Smake_vector);
7392 defsubr (&Smake_string);
7393 defsubr (&Smake_bool_vector);
7394 defsubr (&Smake_symbol);
7395 defsubr (&Smake_marker);
7396 defsubr (&Smake_finalizer);
7397 defsubr (&Spurecopy);
7398 defsubr (&Sgarbage_collect);
7399 defsubr (&Smemory_limit);
7400 defsubr (&Smemory_info);
7401 defsubr (&Smemory_use_counts);
7402 defsubr (&Ssuspicious_object);
7405 /* When compiled with GCC, GDB might say "No enum type named
7406 pvec_type" if we don't have at least one symbol with that type, and
7407 then xbacktrace could fail. Similarly for the other enums and
7408 their values. Some non-GCC compilers don't like these constructs. */
7409 #ifdef __GNUC__
7410 union
7412 enum CHARTAB_SIZE_BITS CHARTAB_SIZE_BITS;
7413 enum char_table_specials char_table_specials;
7414 enum char_bits char_bits;
7415 enum CHECK_LISP_OBJECT_TYPE CHECK_LISP_OBJECT_TYPE;
7416 enum DEFAULT_HASH_SIZE DEFAULT_HASH_SIZE;
7417 enum Lisp_Bits Lisp_Bits;
7418 enum Lisp_Compiled Lisp_Compiled;
7419 enum maxargs maxargs;
7420 enum MAX_ALLOCA MAX_ALLOCA;
7421 enum More_Lisp_Bits More_Lisp_Bits;
7422 enum pvec_type pvec_type;
7423 } const EXTERNALLY_VISIBLE gdb_make_enums_visible = {0};
7424 #endif /* __GNUC__ */