/* Storage allocation and gc for GNU Emacs Lisp interpreter. Copyright (C) 1985, 1986, 1988, 1993, 1994, 1995, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. This file is part of GNU Emacs. GNU Emacs is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU Emacs is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Emacs; see the file COPYING. If not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ #include #include #include /* For CHAR_BIT. */ #ifdef STDC_HEADERS #include /* For offsetof, used by PSEUDOVECSIZE. */ #endif #ifdef ALLOC_DEBUG #undef INLINE #endif /* Note that this declares bzero on OSF/1. How dumb. */ #include #ifdef HAVE_GTK_AND_PTHREAD #include #endif /* This file is part of the core Lisp implementation, and thus must deal with the real data structures. If the Lisp implementation is replaced, this file likely will not be used. */ #undef HIDE_LISP_IMPLEMENTATION #include "lisp.h" #include "process.h" #include "intervals.h" #include "puresize.h" #include "buffer.h" #include "window.h" #include "keyboard.h" #include "frame.h" #include "blockinput.h" #include "charset.h" #include "syssignal.h" #include /* GC_MALLOC_CHECK defined means perform validity checks of malloc'd memory. Can do this only if using gmalloc.c. */ #if defined SYSTEM_MALLOC || defined DOUG_LEA_MALLOC #undef GC_MALLOC_CHECK #endif #ifdef HAVE_UNISTD_H #include #else extern POINTER_TYPE *sbrk (); #endif #ifdef HAVE_FCNTL_H #define INCLUDED_FCNTL #include #endif #ifndef O_WRONLY #define O_WRONLY 1 #endif #ifdef WINDOWSNT #include #include "w32.h" #endif #ifdef DOUG_LEA_MALLOC #include /* malloc.h #defines this as size_t, at least in glibc2. */ #ifndef __malloc_size_t #define __malloc_size_t int #endif /* Specify maximum number of areas to mmap. It would be nice to use a value that explicitly means "no limit". */ #define MMAP_MAX_AREAS 100000000 #else /* not DOUG_LEA_MALLOC */ /* The following come from gmalloc.c. */ #define __malloc_size_t size_t extern __malloc_size_t _bytes_used; extern __malloc_size_t __malloc_extra_blocks; #endif /* not DOUG_LEA_MALLOC */ #if ! defined (SYSTEM_MALLOC) && defined (HAVE_GTK_AND_PTHREAD) /* When GTK uses the file chooser dialog, different backends can be loaded dynamically. One such a backend is the Gnome VFS backend that gets loaded if you run Gnome. That backend creates several threads and also allocates memory with malloc. If Emacs sets malloc hooks (! SYSTEM_MALLOC) and the emacs_blocked_* functions below are called from malloc, there is a chance that one of these threads preempts the Emacs main thread and the hook variables end up in an inconsistent state. So we have a mutex to prevent that (note that the backend handles concurrent access to malloc within its own threads but Emacs code running in the main thread is not included in that control). When UNBLOCK_INPUT is called, reinvoke_input_signal may be called. If this happens in one of the backend threads we will have two threads that tries to run Emacs code at once, and the code is not prepared for that. To prevent that, we only call BLOCK/UNBLOCK from the main thread. */ static pthread_mutex_t alloc_mutex; #define BLOCK_INPUT_ALLOC \ do \ { \ if (pthread_self () == main_thread) \ BLOCK_INPUT; \ pthread_mutex_lock (&alloc_mutex); \ } \ while (0) #define UNBLOCK_INPUT_ALLOC \ do \ { \ pthread_mutex_unlock (&alloc_mutex); \ if (pthread_self () == main_thread) \ UNBLOCK_INPUT; \ } \ while (0) #else /* SYSTEM_MALLOC || not HAVE_GTK_AND_PTHREAD */ #define BLOCK_INPUT_ALLOC BLOCK_INPUT #define UNBLOCK_INPUT_ALLOC UNBLOCK_INPUT #endif /* SYSTEM_MALLOC || not HAVE_GTK_AND_PTHREAD */ /* Value of _bytes_used, when spare_memory was freed. */ static __malloc_size_t bytes_used_when_full; static __malloc_size_t bytes_used_when_reconsidered; /* Mark, unmark, query mark bit of a Lisp string. S must be a pointer to a struct Lisp_String. */ #define MARK_STRING(S) ((S)->size |= ARRAY_MARK_FLAG) #define UNMARK_STRING(S) ((S)->size &= ~ARRAY_MARK_FLAG) #define STRING_MARKED_P(S) (((S)->size & ARRAY_MARK_FLAG) != 0) #define VECTOR_MARK(V) ((V)->size |= ARRAY_MARK_FLAG) #define VECTOR_UNMARK(V) ((V)->size &= ~ARRAY_MARK_FLAG) #define VECTOR_MARKED_P(V) (((V)->size & ARRAY_MARK_FLAG) != 0) /* Value is the number of bytes/chars of S, a pointer to a struct Lisp_String. This must be used instead of STRING_BYTES (S) or S->size during GC, because S->size contains the mark bit for strings. */ #define GC_STRING_BYTES(S) (STRING_BYTES (S)) #define GC_STRING_CHARS(S) ((S)->size & ~ARRAY_MARK_FLAG) /* Number of bytes of consing done since the last gc. */ int consing_since_gc; /* Count the amount of consing of various sorts of space. */ EMACS_INT cons_cells_consed; EMACS_INT floats_consed; EMACS_INT vector_cells_consed; EMACS_INT symbols_consed; EMACS_INT string_chars_consed; EMACS_INT misc_objects_consed; EMACS_INT intervals_consed; EMACS_INT strings_consed; /* Minimum number of bytes of consing since GC before next GC. */ EMACS_INT gc_cons_threshold; /* Similar minimum, computed from Vgc_cons_percentage. */ EMACS_INT gc_relative_threshold; static Lisp_Object Vgc_cons_percentage; /* Minimum number of bytes of consing since GC before next GC, when memory is full. */ EMACS_INT memory_full_cons_threshold; /* Nonzero during GC. */ int gc_in_progress; /* Nonzero means abort if try to GC. This is for code which is written on the assumption that no GC will happen, so as to verify that assumption. */ int abort_on_gc; /* Nonzero means display messages at beginning and end of GC. */ int garbage_collection_messages; #ifndef VIRT_ADDR_VARIES extern #endif /* VIRT_ADDR_VARIES */ int malloc_sbrk_used; #ifndef VIRT_ADDR_VARIES extern #endif /* VIRT_ADDR_VARIES */ int malloc_sbrk_unused; /* Number of live and free conses etc. */ static int total_conses, total_markers, total_symbols, total_vector_size; static int total_free_conses, total_free_markers, total_free_symbols; static int total_free_floats, total_floats; /* Points to memory space allocated as "spare", to be freed if we run out of memory. We keep one large block, four cons-blocks, and two string blocks. */ char *spare_memory[7]; /* Amount of spare memory to keep in large reserve block. */ #define SPARE_MEMORY (1 << 14) /* Number of extra blocks malloc should get when it needs more core. */ static int malloc_hysteresis; /* Non-nil means defun should do purecopy on the function definition. */ Lisp_Object Vpurify_flag; /* Non-nil means we are handling a memory-full error. */ Lisp_Object Vmemory_full; #ifndef HAVE_SHM /* Initialize it to a nonzero value to force it into data space (rather than bss space). That way unexec will remap it into text space (pure), on some systems. We have not implemented the remapping on more recent systems because this is less important nowadays than in the days of small memories and timesharing. */ EMACS_INT pure[PURESIZE / sizeof (EMACS_INT)] = {1,}; #define PUREBEG (char *) pure #else /* HAVE_SHM */ #define pure PURE_SEG_BITS /* Use shared memory segment */ #define PUREBEG (char *)PURE_SEG_BITS #endif /* HAVE_SHM */ /* Pointer to the pure area, and its size. */ static char *purebeg; static size_t pure_size; /* Number of bytes of pure storage used before pure storage overflowed. If this is non-zero, this implies that an overflow occurred. */ static size_t pure_bytes_used_before_overflow; /* Value is non-zero if P points into pure space. */ #define PURE_POINTER_P(P) \ (((PNTR_COMPARISON_TYPE) (P) \ < (PNTR_COMPARISON_TYPE) ((char *) purebeg + pure_size)) \ && ((PNTR_COMPARISON_TYPE) (P) \ >= (PNTR_COMPARISON_TYPE) purebeg)) /* Total number of bytes allocated in pure storage. */ EMACS_INT pure_bytes_used; /* Index in pure at which next pure Lisp object will be allocated.. */ static EMACS_INT pure_bytes_used_lisp; /* Number of bytes allocated for non-Lisp objects in pure storage. */ static EMACS_INT pure_bytes_used_non_lisp; /* If nonzero, this is a warning delivered by malloc and not yet displayed. */ char *pending_malloc_warning; /* Pre-computed signal argument for use when memory is exhausted. */ Lisp_Object Vmemory_signal_data; /* Maximum amount of C stack to save when a GC happens. */ #ifndef MAX_SAVE_STACK #define MAX_SAVE_STACK 16000 #endif /* Buffer in which we save a copy of the C stack at each GC. */ char *stack_copy; int stack_copy_size; /* Non-zero means ignore malloc warnings. Set during initialization. Currently not used. */ int ignore_warnings; Lisp_Object Qgc_cons_threshold, Qchar_table_extra_slots; /* Hook run after GC has finished. */ Lisp_Object Vpost_gc_hook, Qpost_gc_hook; Lisp_Object Vgc_elapsed; /* accumulated elapsed time in GC */ EMACS_INT gcs_done; /* accumulated GCs */ static void mark_buffer P_ ((Lisp_Object)); extern void mark_kboards P_ ((void)); extern void mark_backtrace P_ ((void)); static void gc_sweep P_ ((void)); static void mark_glyph_matrix P_ ((struct glyph_matrix *)); static void mark_face_cache P_ ((struct face_cache *)); #ifdef HAVE_WINDOW_SYSTEM extern void mark_fringe_data P_ ((void)); static void mark_image P_ ((struct image *)); static void mark_image_cache P_ ((struct frame *)); #endif /* HAVE_WINDOW_SYSTEM */ static struct Lisp_String *allocate_string P_ ((void)); static void compact_small_strings P_ ((void)); static void free_large_strings P_ ((void)); static void sweep_strings P_ ((void)); extern int message_enable_multibyte; /* When scanning the C stack for live Lisp objects, Emacs keeps track of what memory allocated via lisp_malloc is intended for what purpose. This enumeration specifies the type of memory. */ enum mem_type { MEM_TYPE_NON_LISP, MEM_TYPE_BUFFER, MEM_TYPE_CONS, MEM_TYPE_STRING, MEM_TYPE_MISC, MEM_TYPE_SYMBOL, MEM_TYPE_FLOAT, /* Keep the following vector-like types together, with MEM_TYPE_WINDOW being the last, and MEM_TYPE_VECTOR the first. Or change the code of live_vector_p, for instance. */ MEM_TYPE_VECTOR, MEM_TYPE_PROCESS, MEM_TYPE_HASH_TABLE, MEM_TYPE_FRAME, MEM_TYPE_WINDOW }; static POINTER_TYPE *lisp_align_malloc P_ ((size_t, enum mem_type)); static POINTER_TYPE *lisp_malloc P_ ((size_t, enum mem_type)); void refill_memory_reserve (); #if GC_MARK_STACK || defined GC_MALLOC_CHECK #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES #include /* For fprintf. */ #endif /* A unique object in pure space used to make some Lisp objects on free lists recognizable in O(1). */ Lisp_Object Vdead; #ifdef GC_MALLOC_CHECK enum mem_type allocated_mem_type; int dont_register_blocks; #endif /* GC_MALLOC_CHECK */ /* A node in the red-black tree describing allocated memory containing Lisp data. Each such block is recorded with its start and end address when it is allocated, and removed from the tree when it is freed. A red-black tree is a balanced binary tree with the following properties: 1. Every node is either red or black. 2. Every leaf is black. 3. If a node is red, then both of its children are black. 4. Every simple path from a node to a descendant leaf contains the same number of black nodes. 5. The root is always black. When nodes are inserted into the tree, or deleted from the tree, the tree is "fixed" so that these properties are always true. A red-black tree with N internal nodes has height at most 2 log(N+1). Searches, insertions and deletions are done in O(log N). Please see a text book about data structures for a detailed description of red-black trees. Any book worth its salt should describe them. */ struct mem_node { /* Children of this node. These pointers are never NULL. When there is no child, the value is MEM_NIL, which points to a dummy node. */ struct mem_node *left, *right; /* The parent of this node. In the root node, this is NULL. */ struct mem_node *parent; /* Start and end of allocated region. */ void *start, *end; /* Node color. */ enum {MEM_BLACK, MEM_RED} color; /* Memory type. */ enum mem_type type; }; /* Base address of stack. Set in main. */ Lisp_Object *stack_base; /* Root of the tree describing allocated Lisp memory. */ static struct mem_node *mem_root; /* Lowest and highest known address in the heap. */ static void *min_heap_address, *max_heap_address; /* Sentinel node of the tree. */ static struct mem_node mem_z; #define MEM_NIL &mem_z static POINTER_TYPE *lisp_malloc P_ ((size_t, enum mem_type)); static struct Lisp_Vector *allocate_vectorlike P_ ((EMACS_INT, enum mem_type)); static void lisp_free P_ ((POINTER_TYPE *)); static void mark_stack P_ ((void)); static int live_vector_p P_ ((struct mem_node *, void *)); static int live_buffer_p P_ ((struct mem_node *, void *)); static int live_string_p P_ ((struct mem_node *, void *)); static int live_cons_p P_ ((struct mem_node *, void *)); static int live_symbol_p P_ ((struct mem_node *, void *)); static int live_float_p P_ ((struct mem_node *, void *)); static int live_misc_p P_ ((struct mem_node *, void *)); static void mark_maybe_object P_ ((Lisp_Object)); static void mark_memory P_ ((void *, void *)); static void mem_init P_ ((void)); static struct mem_node *mem_insert P_ ((void *, void *, enum mem_type)); static void mem_insert_fixup P_ ((struct mem_node *)); static void mem_rotate_left P_ ((struct mem_node *)); static void mem_rotate_right P_ ((struct mem_node *)); static void mem_delete P_ ((struct mem_node *)); static void mem_delete_fixup P_ ((struct mem_node *)); static INLINE struct mem_node *mem_find P_ ((void *)); #if GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS static void check_gcpros P_ ((void)); #endif #endif /* GC_MARK_STACK || GC_MALLOC_CHECK */ /* Recording what needs to be marked for gc. */ struct gcpro *gcprolist; /* Addresses of staticpro'd variables. Initialize it to a nonzero value; otherwise some compilers put it into BSS. */ #define NSTATICS 1280 Lisp_Object *staticvec[NSTATICS] = {&Vpurify_flag}; /* Index of next unused slot in staticvec. */ int staticidx = 0; static POINTER_TYPE *pure_alloc P_ ((size_t, int)); /* Value is SZ rounded up to the next multiple of ALIGNMENT. ALIGNMENT must be a power of 2. */ #define ALIGN(ptr, ALIGNMENT) \ ((POINTER_TYPE *) ((((EMACS_UINT)(ptr)) + (ALIGNMENT) - 1) \ & ~((ALIGNMENT) - 1))) /************************************************************************ Malloc ************************************************************************/ /* Function malloc calls this if it finds we are near exhausting storage. */ void malloc_warning (str) char *str; { pending_malloc_warning = str; } /* Display an already-pending malloc warning. */ void display_malloc_warning () { call3 (intern ("display-warning"), intern ("alloc"), build_string (pending_malloc_warning), intern ("emergency")); pending_malloc_warning = 0; } #ifdef DOUG_LEA_MALLOC # define BYTES_USED (mallinfo ().uordblks) #else # define BYTES_USED _bytes_used #endif /* Called if we can't allocate relocatable space for a buffer. */ void buffer_memory_full () { /* If buffers use the relocating allocator, no need to free spare_memory, because we may have plenty of malloc space left that we could get, and if we don't, the malloc that fails will itself cause spare_memory to be freed. If buffers don't use the relocating allocator, treat this like any other failing malloc. */ #ifndef REL_ALLOC memory_full (); #endif /* This used to call error, but if we've run out of memory, we could get infinite recursion trying to build the string. */ xsignal (Qnil, Vmemory_signal_data); } #ifdef XMALLOC_OVERRUN_CHECK /* Check for overrun in malloc'ed buffers by wrapping a 16 byte header and a 16 byte trailer around each block. The header consists of 12 fixed bytes + a 4 byte integer contaning the original block size, while the trailer consists of 16 fixed bytes. The header is used to detect whether this block has been allocated through these functions -- as it seems that some low-level libc functions may bypass the malloc hooks. */ #define XMALLOC_OVERRUN_CHECK_SIZE 16 static char xmalloc_overrun_check_header[XMALLOC_OVERRUN_CHECK_SIZE-4] = { 0x9a, 0x9b, 0xae, 0xaf, 0xbf, 0xbe, 0xce, 0xcf, 0xea, 0xeb, 0xec, 0xed }; static char xmalloc_overrun_check_trailer[XMALLOC_OVERRUN_CHECK_SIZE] = { 0xaa, 0xab, 0xac, 0xad, 0xba, 0xbb, 0xbc, 0xbd, 0xca, 0xcb, 0xcc, 0xcd, 0xda, 0xdb, 0xdc, 0xdd }; /* Macros to insert and extract the block size in the header. */ #define XMALLOC_PUT_SIZE(ptr, size) \ (ptr[-1] = (size & 0xff), \ ptr[-2] = ((size >> 8) & 0xff), \ ptr[-3] = ((size >> 16) & 0xff), \ ptr[-4] = ((size >> 24) & 0xff)) #define XMALLOC_GET_SIZE(ptr) \ (size_t)((unsigned)(ptr[-1]) | \ ((unsigned)(ptr[-2]) << 8) | \ ((unsigned)(ptr[-3]) << 16) | \ ((unsigned)(ptr[-4]) << 24)) /* The call depth in overrun_check functions. For example, this might happen: xmalloc() overrun_check_malloc() -> malloc -> (via hook)_-> emacs_blocked_malloc -> overrun_check_malloc call malloc (hooks are NULL, so real malloc is called). malloc returns 10000. add overhead, return 10016. <- (back in overrun_check_malloc) add overhead again, return 10032 xmalloc returns 10032. (time passes). xfree(10032) overrun_check_free(10032) decrease overhed free(10016) <- crash, because 10000 is the original pointer. */ static int check_depth; /* Like malloc, but wraps allocated block with header and trailer. */ POINTER_TYPE * overrun_check_malloc (size) size_t size; { register unsigned char *val; size_t overhead = ++check_depth == 1 ? XMALLOC_OVERRUN_CHECK_SIZE*2 : 0; val = (unsigned char *) malloc (size + overhead); if (val && check_depth == 1) { bcopy (xmalloc_overrun_check_header, val, XMALLOC_OVERRUN_CHECK_SIZE - 4); val += XMALLOC_OVERRUN_CHECK_SIZE; XMALLOC_PUT_SIZE(val, size); bcopy (xmalloc_overrun_check_trailer, val + size, XMALLOC_OVERRUN_CHECK_SIZE); } --check_depth; return (POINTER_TYPE *)val; } /* Like realloc, but checks old block for overrun, and wraps new block with header and trailer. */ POINTER_TYPE * overrun_check_realloc (block, size) POINTER_TYPE *block; size_t size; { register unsigned char *val = (unsigned char *)block; size_t overhead = ++check_depth == 1 ? XMALLOC_OVERRUN_CHECK_SIZE*2 : 0; if (val && check_depth == 1 && bcmp (xmalloc_overrun_check_header, val - XMALLOC_OVERRUN_CHECK_SIZE, XMALLOC_OVERRUN_CHECK_SIZE - 4) == 0) { size_t osize = XMALLOC_GET_SIZE (val); if (bcmp (xmalloc_overrun_check_trailer, val + osize, XMALLOC_OVERRUN_CHECK_SIZE)) abort (); bzero (val + osize, XMALLOC_OVERRUN_CHECK_SIZE); val -= XMALLOC_OVERRUN_CHECK_SIZE; bzero (val, XMALLOC_OVERRUN_CHECK_SIZE); } val = (unsigned char *) realloc ((POINTER_TYPE *)val, size + overhead); if (val && check_depth == 1) { bcopy (xmalloc_overrun_check_header, val, XMALLOC_OVERRUN_CHECK_SIZE - 4); val += XMALLOC_OVERRUN_CHECK_SIZE; XMALLOC_PUT_SIZE(val, size); bcopy (xmalloc_overrun_check_trailer, val + size, XMALLOC_OVERRUN_CHECK_SIZE); } --check_depth; return (POINTER_TYPE *)val; } /* Like free, but checks block for overrun. */ void overrun_check_free (block) POINTER_TYPE *block; { unsigned char *val = (unsigned char *)block; ++check_depth; if (val && check_depth == 1 && bcmp (xmalloc_overrun_check_header, val - XMALLOC_OVERRUN_CHECK_SIZE, XMALLOC_OVERRUN_CHECK_SIZE - 4) == 0) { size_t osize = XMALLOC_GET_SIZE (val); if (bcmp (xmalloc_overrun_check_trailer, val + osize, XMALLOC_OVERRUN_CHECK_SIZE)) abort (); #ifdef XMALLOC_CLEAR_FREE_MEMORY val -= XMALLOC_OVERRUN_CHECK_SIZE; memset (val, 0xff, osize + XMALLOC_OVERRUN_CHECK_SIZE*2); #else bzero (val + osize, XMALLOC_OVERRUN_CHECK_SIZE); val -= XMALLOC_OVERRUN_CHECK_SIZE; bzero (val, XMALLOC_OVERRUN_CHECK_SIZE); #endif } free (val); --check_depth; } #undef malloc #undef realloc #undef free #define malloc overrun_check_malloc #define realloc overrun_check_realloc #define free overrun_check_free #endif /* Like malloc but check for no memory and block interrupt input.. */ POINTER_TYPE * xmalloc (size) size_t size; { register POINTER_TYPE *val; BLOCK_INPUT; val = (POINTER_TYPE *) malloc (size); UNBLOCK_INPUT; if (!val && size) memory_full (); return val; } /* Like realloc but check for no memory and block interrupt input.. */ POINTER_TYPE * xrealloc (block, size) POINTER_TYPE *block; size_t size; { register POINTER_TYPE *val; BLOCK_INPUT; /* We must call malloc explicitly when BLOCK is 0, since some reallocs don't do this. */ if (! block) val = (POINTER_TYPE *) malloc (size); else val = (POINTER_TYPE *) realloc (block, size); UNBLOCK_INPUT; if (!val && size) memory_full (); return val; } /* Like free but block interrupt input. */ void xfree (block) POINTER_TYPE *block; { BLOCK_INPUT; free (block); UNBLOCK_INPUT; /* We don't call refill_memory_reserve here because that duplicates doing so in emacs_blocked_free and the criterion should go there. */ } /* Like strdup, but uses xmalloc. */ char * xstrdup (s) const char *s; { size_t len = strlen (s) + 1; char *p = (char *) xmalloc (len); bcopy (s, p, len); return p; } /* Unwind for SAFE_ALLOCA */ Lisp_Object safe_alloca_unwind (arg) Lisp_Object arg; { register struct Lisp_Save_Value *p = XSAVE_VALUE (arg); p->dogc = 0; xfree (p->pointer); p->pointer = 0; free_misc (arg); return Qnil; } /* Like malloc but used for allocating Lisp data. NBYTES is the number of bytes to allocate, TYPE describes the intended use of the allcated memory block (for strings, for conses, ...). */ #ifndef USE_LSB_TAG static void *lisp_malloc_loser; #endif static POINTER_TYPE * lisp_malloc (nbytes, type) size_t nbytes; enum mem_type type; { register void *val; BLOCK_INPUT; #ifdef GC_MALLOC_CHECK allocated_mem_type = type; #endif val = (void *) malloc (nbytes); #ifndef USE_LSB_TAG /* If the memory just allocated cannot be addressed thru a Lisp object's pointer, and it needs to be, that's equivalent to running out of memory. */ if (val && type != MEM_TYPE_NON_LISP) { Lisp_Object tem; XSETCONS (tem, (char *) val + nbytes - 1); if ((char *) XCONS (tem) != (char *) val + nbytes - 1) { lisp_malloc_loser = val; free (val); val = 0; } } #endif #if GC_MARK_STACK && !defined GC_MALLOC_CHECK if (val && type != MEM_TYPE_NON_LISP) mem_insert (val, (char *) val + nbytes, type); #endif UNBLOCK_INPUT; if (!val && nbytes) memory_full (); return val; } /* Free BLOCK. This must be called to free memory allocated with a call to lisp_malloc. */ static void lisp_free (block) POINTER_TYPE *block; { BLOCK_INPUT; free (block); #if GC_MARK_STACK && !defined GC_MALLOC_CHECK mem_delete (mem_find (block)); #endif UNBLOCK_INPUT; } /* Allocation of aligned blocks of memory to store Lisp data. */ /* The entry point is lisp_align_malloc which returns blocks of at most */ /* BLOCK_BYTES and guarantees they are aligned on a BLOCK_ALIGN boundary. */ /* Use posix_memalloc if the system has it and we're using the system's malloc (because our gmalloc.c routines don't have posix_memalign although its memalloc could be used). */ #if defined (HAVE_POSIX_MEMALIGN) && defined (SYSTEM_MALLOC) #define USE_POSIX_MEMALIGN 1 #endif /* BLOCK_ALIGN has to be a power of 2. */ #define BLOCK_ALIGN (1 << 10) /* Padding to leave at the end of a malloc'd block. This is to give malloc a chance to minimize the amount of memory wasted to alignment. It should be tuned to the particular malloc library used. On glibc-2.3.2, malloc never tries to align, so a padding of 0 is best. posix_memalign on the other hand would ideally prefer a value of 4 because otherwise, there's 1020 bytes wasted between each ablocks. In Emacs, testing shows that those 1020 can most of the time be efficiently used by malloc to place other objects, so a value of 0 can still preferable unless you have a lot of aligned blocks and virtually nothing else. */ #define BLOCK_PADDING 0 #define BLOCK_BYTES \ (BLOCK_ALIGN - sizeof (struct ablock *) - BLOCK_PADDING) /* Internal data structures and constants. */ #define ABLOCKS_SIZE 16 /* An aligned block of memory. */ struct ablock { union { char payload[BLOCK_BYTES]; struct ablock *next_free; } x; /* `abase' is the aligned base of the ablocks. */ /* It is overloaded to hold the virtual `busy' field that counts the number of used ablock in the parent ablocks. The first ablock has the `busy' field, the others have the `abase' field. To tell the difference, we assume that pointers will have integer values larger than 2 * ABLOCKS_SIZE. The lowest bit of `busy' is used to tell whether the real base of the parent ablocks is `abase' (if not, the word before the first ablock holds a pointer to the real base). */ struct ablocks *abase; /* The padding of all but the last ablock is unused. The padding of the last ablock in an ablocks is not allocated. */ #if BLOCK_PADDING char padding[BLOCK_PADDING]; #endif }; /* A bunch of consecutive aligned blocks. */ struct ablocks { struct ablock blocks[ABLOCKS_SIZE]; }; /* Size of the block requested from malloc or memalign. */ #define ABLOCKS_BYTES (sizeof (struct ablocks) - BLOCK_PADDING) #define ABLOCK_ABASE(block) \ (((unsigned long) (block)->abase) <= (1 + 2 * ABLOCKS_SIZE) \ ? (struct ablocks *)(block) \ : (block)->abase) /* Virtual `busy' field. */ #define ABLOCKS_BUSY(abase) ((abase)->blocks[0].abase) /* Pointer to the (not necessarily aligned) malloc block. */ #ifdef USE_POSIX_MEMALIGN #define ABLOCKS_BASE(abase) (abase) #else #define ABLOCKS_BASE(abase) \ (1 & (long) ABLOCKS_BUSY (abase) ? abase : ((void**)abase)[-1]) #endif /* The list of free ablock. */ static struct ablock *free_ablock; /* Allocate an aligned block of nbytes. Alignment is on a multiple of BLOCK_ALIGN and `nbytes' has to be smaller or equal to BLOCK_BYTES. */ static POINTER_TYPE * lisp_align_malloc (nbytes, type) size_t nbytes; enum mem_type type; { void *base, *val; struct ablocks *abase; eassert (nbytes <= BLOCK_BYTES); BLOCK_INPUT; #ifdef GC_MALLOC_CHECK allocated_mem_type = type; #endif if (!free_ablock) { int i; EMACS_INT aligned; /* int gets warning casting to 64-bit pointer. */ #ifdef DOUG_LEA_MALLOC /* Prevent mmap'ing the chunk. Lisp data may not be mmap'ed because mapped region contents are not preserved in a dumped Emacs. */ mallopt (M_MMAP_MAX, 0); #endif #ifdef USE_POSIX_MEMALIGN { int err = posix_memalign (&base, BLOCK_ALIGN, ABLOCKS_BYTES); if (err) base = NULL; abase = base; } #else base = malloc (ABLOCKS_BYTES); abase = ALIGN (base, BLOCK_ALIGN); #endif if (base == 0) { UNBLOCK_INPUT; memory_full (); } aligned = (base == abase); if (!aligned) ((void**)abase)[-1] = base; #ifdef DOUG_LEA_MALLOC /* Back to a reasonable maximum of mmap'ed areas. */ mallopt (M_MMAP_MAX, MMAP_MAX_AREAS); #endif #ifndef USE_LSB_TAG /* If the memory just allocated cannot be addressed thru a Lisp object's pointer, and it needs to be, that's equivalent to running out of memory. */ if (type != MEM_TYPE_NON_LISP) { Lisp_Object tem; char *end = (char *) base + ABLOCKS_BYTES - 1; XSETCONS (tem, end); if ((char *) XCONS (tem) != end) { lisp_malloc_loser = base; free (base); UNBLOCK_INPUT; memory_full (); } } #endif /* Initialize the blocks and put them on the free list. Is `base' was not properly aligned, we can't use the last block. */ for (i = 0; i < (aligned ? ABLOCKS_SIZE : ABLOCKS_SIZE - 1); i++) { abase->blocks[i].abase = abase; abase->blocks[i].x.next_free = free_ablock; free_ablock = &abase->blocks[i]; } ABLOCKS_BUSY (abase) = (struct ablocks *) (long) aligned; eassert (0 == ((EMACS_UINT)abase) % BLOCK_ALIGN); eassert (ABLOCK_ABASE (&abase->blocks[3]) == abase); /* 3 is arbitrary */ eassert (ABLOCK_ABASE (&abase->blocks[0]) == abase); eassert (ABLOCKS_BASE (abase) == base); eassert (aligned == (long) ABLOCKS_BUSY (abase)); } abase = ABLOCK_ABASE (free_ablock); ABLOCKS_BUSY (abase) = (struct ablocks *) (2 + (long) ABLOCKS_BUSY (abase)); val = free_ablock; free_ablock = free_ablock->x.next_free; #if GC_MARK_STACK && !defined GC_MALLOC_CHECK if (val && type != MEM_TYPE_NON_LISP) mem_insert (val, (char *) val + nbytes, type); #endif UNBLOCK_INPUT; if (!val && nbytes) memory_full (); eassert (0 == ((EMACS_UINT)val) % BLOCK_ALIGN); return val; } static void lisp_align_free (block) POINTER_TYPE *block; { struct ablock *ablock = block; struct ablocks *abase = ABLOCK_ABASE (ablock); BLOCK_INPUT; #if GC_MARK_STACK && !defined GC_MALLOC_CHECK mem_delete (mem_find (block)); #endif /* Put on free list. */ ablock->x.next_free = free_ablock; free_ablock = ablock; /* Update busy count. */ ABLOCKS_BUSY (abase) = (struct ablocks *) (-2 + (long) ABLOCKS_BUSY (abase)); if (2 > (long) ABLOCKS_BUSY (abase)) { /* All the blocks are free. */ int i = 0, aligned = (long) ABLOCKS_BUSY (abase); struct ablock **tem = &free_ablock; struct ablock *atop = &abase->blocks[aligned ? ABLOCKS_SIZE : ABLOCKS_SIZE - 1]; while (*tem) { if (*tem >= (struct ablock *) abase && *tem < atop) { i++; *tem = (*tem)->x.next_free; } else tem = &(*tem)->x.next_free; } eassert ((aligned & 1) == aligned); eassert (i == (aligned ? ABLOCKS_SIZE : ABLOCKS_SIZE - 1)); #ifdef USE_POSIX_MEMALIGN eassert ((unsigned long)ABLOCKS_BASE (abase) % BLOCK_ALIGN == 0); #endif free (ABLOCKS_BASE (abase)); } UNBLOCK_INPUT; } /* Return a new buffer structure allocated from the heap with a call to lisp_malloc. */ struct buffer * allocate_buffer () { struct buffer *b = (struct buffer *) lisp_malloc (sizeof (struct buffer), MEM_TYPE_BUFFER); return b; } #ifndef SYSTEM_MALLOC /* Arranging to disable input signals while we're in malloc. This only works with GNU malloc. To help out systems which can't use GNU malloc, all the calls to malloc, realloc, and free elsewhere in the code should be inside a BLOCK_INPUT/UNBLOCK_INPUT pair; unfortunately, we have no idea what C library functions might call malloc, so we can't really protect them unless you're using GNU malloc. Fortunately, most of the major operating systems can use GNU malloc. */ #ifndef SYNC_INPUT #ifndef DOUG_LEA_MALLOC extern void * (*__malloc_hook) P_ ((size_t, const void *)); extern void * (*__realloc_hook) P_ ((void *, size_t, const void *)); extern void (*__free_hook) P_ ((void *, const void *)); /* Else declared in malloc.h, perhaps with an extra arg. */ #endif /* DOUG_LEA_MALLOC */ static void * (*old_malloc_hook) P_ ((size_t, const void *)); static void * (*old_realloc_hook) P_ ((void *, size_t, const void*)); static void (*old_free_hook) P_ ((void*, const void*)); /* This function is used as the hook for free to call. */ static void emacs_blocked_free (ptr, ptr2) void *ptr; const void *ptr2; { EMACS_INT bytes_used_now; BLOCK_INPUT_ALLOC; #ifdef GC_MALLOC_CHECK if (ptr) { struct mem_node *m; m = mem_find (ptr); if (m == MEM_NIL || m->start != ptr) { fprintf (stderr, "Freeing `%p' which wasn't allocated with malloc\n", ptr); abort (); } else { /* fprintf (stderr, "free %p...%p (%p)\n", m->start, m->end, ptr); */ mem_delete (m); } } #endif /* GC_MALLOC_CHECK */ __free_hook = old_free_hook; free (ptr); /* If we released our reserve (due to running out of memory), and we have a fair amount free once again, try to set aside another reserve in case we run out once more. */ if (! NILP (Vmemory_full) /* Verify there is enough space that even with the malloc hysteresis this call won't run out again. The code here is correct as long as SPARE_MEMORY is substantially larger than the block size malloc uses. */ && (bytes_used_when_full > ((bytes_used_when_reconsidered = BYTES_USED) + max (malloc_hysteresis, 4) * SPARE_MEMORY))) refill_memory_reserve (); __free_hook = emacs_blocked_free; UNBLOCK_INPUT_ALLOC; } /* This function is the malloc hook that Emacs uses. */ static void * emacs_blocked_malloc (size, ptr) size_t size; const void *ptr; { void *value; BLOCK_INPUT_ALLOC; __malloc_hook = old_malloc_hook; #ifdef DOUG_LEA_MALLOC mallopt (M_TOP_PAD, malloc_hysteresis * 4096); #else __malloc_extra_blocks = malloc_hysteresis; #endif value = (void *) malloc (size); #ifdef GC_MALLOC_CHECK { struct mem_node *m = mem_find (value); if (m != MEM_NIL) { fprintf (stderr, "Malloc returned %p which is already in use\n", value); fprintf (stderr, "Region in use is %p...%p, %u bytes, type %d\n", m->start, m->end, (char *) m->end - (char *) m->start, m->type); abort (); } if (!dont_register_blocks) { mem_insert (value, (char *) value + max (1, size), allocated_mem_type); allocated_mem_type = MEM_TYPE_NON_LISP; } } #endif /* GC_MALLOC_CHECK */ __malloc_hook = emacs_blocked_malloc; UNBLOCK_INPUT_ALLOC; /* fprintf (stderr, "%p malloc\n", value); */ return value; } /* This function is the realloc hook that Emacs uses. */ static void * emacs_blocked_realloc (ptr, size, ptr2) void *ptr; size_t size; const void *ptr2; { void *value; BLOCK_INPUT_ALLOC; __realloc_hook = old_realloc_hook; #ifdef GC_MALLOC_CHECK if (ptr) { struct mem_node *m = mem_find (ptr); if (m == MEM_NIL || m->start != ptr) { fprintf (stderr, "Realloc of %p which wasn't allocated with malloc\n", ptr); abort (); } mem_delete (m); } /* fprintf (stderr, "%p -> realloc\n", ptr); */ /* Prevent malloc from registering blocks. */ dont_register_blocks = 1; #endif /* GC_MALLOC_CHECK */ value = (void *) realloc (ptr, size); #ifdef GC_MALLOC_CHECK dont_register_blocks = 0; { struct mem_node *m = mem_find (value); if (m != MEM_NIL) { fprintf (stderr, "Realloc returns memory that is already in use\n"); abort (); } /* Can't handle zero size regions in the red-black tree. */ mem_insert (value, (char *) value + max (size, 1), MEM_TYPE_NON_LISP); } /* fprintf (stderr, "%p <- realloc\n", value); */ #endif /* GC_MALLOC_CHECK */ __realloc_hook = emacs_blocked_realloc; UNBLOCK_INPUT_ALLOC; return value; } #ifdef HAVE_GTK_AND_PTHREAD /* Called from Fdump_emacs so that when the dumped Emacs starts, it has a normal malloc. Some thread implementations need this as they call malloc before main. The pthread_self call in BLOCK_INPUT_ALLOC then calls malloc because it is the first call, and we have an endless loop. */ void reset_malloc_hooks () { __free_hook = 0; __malloc_hook = 0; __realloc_hook = 0; } #endif /* HAVE_GTK_AND_PTHREAD */ /* Called from main to set up malloc to use our hooks. */ void uninterrupt_malloc () { #ifdef HAVE_GTK_AND_PTHREAD pthread_mutexattr_t attr; /* GLIBC has a faster way to do this, but lets keep it portable. This is according to the Single UNIX Specification. */ pthread_mutexattr_init (&attr); pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_RECURSIVE); pthread_mutex_init (&alloc_mutex, &attr); #endif /* HAVE_GTK_AND_PTHREAD */ if (__free_hook != emacs_blocked_free) old_free_hook = __free_hook; __free_hook = emacs_blocked_free; if (__malloc_hook != emacs_blocked_malloc) old_malloc_hook = __malloc_hook; __malloc_hook = emacs_blocked_malloc; if (__realloc_hook != emacs_blocked_realloc) old_realloc_hook = __realloc_hook; __realloc_hook = emacs_blocked_realloc; } #endif /* not SYNC_INPUT */ #endif /* not SYSTEM_MALLOC */ /*********************************************************************** Interval Allocation ***********************************************************************/ /* Number of intervals allocated in an interval_block structure. The 1020 is 1024 minus malloc overhead. */ #define INTERVAL_BLOCK_SIZE \ ((1020 - sizeof (struct interval_block *)) / sizeof (struct interval)) /* Intervals are allocated in chunks in form of an interval_block structure. */ struct interval_block { /* Place `intervals' first, to preserve alignment. */ struct interval intervals[INTERVAL_BLOCK_SIZE]; struct interval_block *next; }; /* Current interval block. Its `next' pointer points to older blocks. */ struct interval_block *interval_block; /* Index in interval_block above of the next unused interval structure. */ static int interval_block_index; /* Number of free and live intervals. */ static int total_free_intervals, total_intervals; /* List of free intervals. */ INTERVAL interval_free_list; /* Total number of interval blocks now in use. */ int n_interval_blocks; /* Initialize interval allocation. */ static void init_intervals () { interval_block = NULL; interval_block_index = INTERVAL_BLOCK_SIZE; interval_free_list = 0; n_interval_blocks = 0; } /* Return a new interval. */ INTERVAL make_interval () { INTERVAL val; /* eassert (!handling_signal); */ #ifndef SYNC_INPUT BLOCK_INPUT; #endif if (interval_free_list) { val = interval_free_list; interval_free_list = INTERVAL_PARENT (interval_free_list); } else { if (interval_block_index == INTERVAL_BLOCK_SIZE) { register struct interval_block *newi; newi = (struct interval_block *) lisp_malloc (sizeof *newi, MEM_TYPE_NON_LISP); newi->next = interval_block; interval_block = newi; interval_block_index = 0; n_interval_blocks++; } val = &interval_block->intervals[interval_block_index++]; } #ifndef SYNC_INPUT UNBLOCK_INPUT; #endif consing_since_gc += sizeof (struct interval); intervals_consed++; RESET_INTERVAL (val); val->gcmarkbit = 0; return val; } /* Mark Lisp objects in interval I. */ static void mark_interval (i, dummy) register INTERVAL i; Lisp_Object dummy; { eassert (!i->gcmarkbit); /* Intervals are never shared. */ i->gcmarkbit = 1; mark_object (i->plist); } /* Mark the interval tree rooted in TREE. Don't call this directly; use the macro MARK_INTERVAL_TREE instead. */ static void mark_interval_tree (tree) register INTERVAL tree; { /* No need to test if this tree has been marked already; this function is always called through the MARK_INTERVAL_TREE macro, which takes care of that. */ traverse_intervals_noorder (tree, mark_interval, Qnil); } /* Mark the interval tree rooted in I. */ #define MARK_INTERVAL_TREE(i) \ do { \ if (!NULL_INTERVAL_P (i) && !i->gcmarkbit) \ mark_interval_tree (i); \ } while (0) #define UNMARK_BALANCE_INTERVALS(i) \ do { \ if (! NULL_INTERVAL_P (i)) \ (i) = balance_intervals (i); \ } while (0) /* Number support. If NO_UNION_TYPE isn't in effect, we can't create number objects in macros. */ #ifndef make_number Lisp_Object make_number (n) EMACS_INT n; { Lisp_Object obj; obj.s.val = n; obj.s.type = Lisp_Int; return obj; } #endif /*********************************************************************** String Allocation ***********************************************************************/ /* Lisp_Strings are allocated in string_block structures. When a new string_block is allocated, all the Lisp_Strings it contains are added to a free-list string_free_list. When a new Lisp_String is needed, it is taken from that list. During the sweep phase of GC, string_blocks that are entirely free are freed, except two which we keep. String data is allocated from sblock structures. Strings larger than LARGE_STRING_BYTES, get their own sblock, data for smaller strings is sub-allocated out of sblocks of size SBLOCK_SIZE. Sblocks consist internally of sdata structures, one for each Lisp_String. The sdata structure points to the Lisp_String it belongs to. The Lisp_String points back to the `u.data' member of its sdata structure. When a Lisp_String is freed during GC, it is put back on string_free_list, and its `data' member and its sdata's `string' pointer is set to null. The size of the string is recorded in the `u.nbytes' member of the sdata. So, sdata structures that are no longer used, can be easily recognized, and it's easy to compact the sblocks of small strings which we do in compact_small_strings. */ /* Size in bytes of an sblock structure used for small strings. This is 8192 minus malloc overhead. */ #define SBLOCK_SIZE 8188 /* Strings larger than this are considered large strings. String data for large strings is allocated from individual sblocks. */ #define LARGE_STRING_BYTES 1024 /* Structure describing string memory sub-allocated from an sblock. This is where the contents of Lisp strings are stored. */ struct sdata { /* Back-pointer to the string this sdata belongs to. If null, this structure is free, and the NBYTES member of the union below contains the string's byte size (the same value that STRING_BYTES would return if STRING were non-null). If non-null, STRING_BYTES (STRING) is the size of the data, and DATA contains the string's contents. */ struct Lisp_String *string; #ifdef GC_CHECK_STRING_BYTES EMACS_INT nbytes; unsigned char data[1]; #define SDATA_NBYTES(S) (S)->nbytes #define SDATA_DATA(S) (S)->data #else /* not GC_CHECK_STRING_BYTES */ union { /* When STRING in non-null. */ unsigned char data[1]; /* When STRING is null. */ EMACS_INT nbytes; } u; #define SDATA_NBYTES(S) (S)->u.nbytes #define SDATA_DATA(S) (S)->u.data #endif /* not GC_CHECK_STRING_BYTES */ }; /* Structure describing a block of memory which is sub-allocated to obtain string data memory for strings. Blocks for small strings are of fixed size SBLOCK_SIZE. Blocks for large strings are made as large as needed. */ struct sblock { /* Next in list. */ struct sblock *next; /* Pointer to the next free sdata block. This points past the end of the sblock if there isn't any space left in this block. */ struct sdata *next_free; /* Start of data. */ struct sdata first_data; }; /* Number of Lisp strings in a string_block structure. The 1020 is 1024 minus malloc overhead. */ #define STRING_BLOCK_SIZE \ ((1020 - sizeof (struct string_block *)) / sizeof (struct Lisp_String)) /* Structure describing a block from which Lisp_String structures are allocated. */ struct string_block { /* Place `strings' first, to preserve alignment. */ struct Lisp_String strings[STRING_BLOCK_SIZE]; struct string_block *next; }; /* Head and tail of the list of sblock structures holding Lisp string data. We always allocate from current_sblock. The NEXT pointers in the sblock structures go from oldest_sblock to current_sblock. */ static struct sblock *oldest_sblock, *current_sblock; /* List of sblocks for large strings. */ static struct sblock *large_sblocks; /* List of string_block structures, and how many there are. */ static struct string_block *string_blocks; static int n_string_blocks; /* Free-list of Lisp_Strings. */ static struct Lisp_String *string_free_list; /* Number of live and free Lisp_Strings. */ static int total_strings, total_free_strings; /* Number of bytes used by live strings. */ static int total_string_size; /* Given a pointer to a Lisp_String S which is on the free-list string_free_list, return a pointer to its successor in the free-list. */ #define NEXT_FREE_LISP_STRING(S) (*(struct Lisp_String **) (S)) /* Return a pointer to the sdata structure belonging to Lisp string S. S must be live, i.e. S->data must not be null. S->data is actually a pointer to the `u.data' member of its sdata structure; the structure starts at a constant offset in front of that. */ #ifdef GC_CHECK_STRING_BYTES #define SDATA_OF_STRING(S) \ ((struct sdata *) ((S)->data - sizeof (struct Lisp_String *) \ - sizeof (EMACS_INT))) #else /* not GC_CHECK_STRING_BYTES */ #define SDATA_OF_STRING(S) \ ((struct sdata *) ((S)->data - sizeof (struct Lisp_String *))) #endif /* not GC_CHECK_STRING_BYTES */ #ifdef GC_CHECK_STRING_OVERRUN /* We check for overrun in string data blocks by appending a small "cookie" after each allocated string data block, and check for the presence of this cookie during GC. */ #define GC_STRING_OVERRUN_COOKIE_SIZE 4 static char string_overrun_cookie[GC_STRING_OVERRUN_COOKIE_SIZE] = { 0xde, 0xad, 0xbe, 0xef }; #else #define GC_STRING_OVERRUN_COOKIE_SIZE 0 #endif /* Value is the size of an sdata structure large enough to hold NBYTES bytes of string data. The value returned includes a terminating NUL byte, the size of the sdata structure, and padding. */ #ifdef GC_CHECK_STRING_BYTES #define SDATA_SIZE(NBYTES) \ ((sizeof (struct Lisp_String *) \ + (NBYTES) + 1 \ + sizeof (EMACS_INT) \ + sizeof (EMACS_INT) - 1) \ & ~(sizeof (EMACS_INT) - 1)) #else /* not GC_CHECK_STRING_BYTES */ #define SDATA_SIZE(NBYTES) \ ((sizeof (struct Lisp_String *) \ + (NBYTES) + 1 \ + sizeof (EMACS_INT) - 1) \ & ~(sizeof (EMACS_INT) - 1)) #endif /* not GC_CHECK_STRING_BYTES */ /* Extra bytes to allocate for each string. */ #define GC_STRING_EXTRA (GC_STRING_OVERRUN_COOKIE_SIZE) /* Initialize string allocation. Called from init_alloc_once. */ void init_strings () { total_strings = total_free_strings = total_string_size = 0; oldest_sblock = current_sblock = large_sblocks = NULL; string_blocks = NULL; n_string_blocks = 0; string_free_list = NULL; } #ifdef GC_CHECK_STRING_BYTES static int check_string_bytes_count; void check_string_bytes P_ ((int)); void check_sblock P_ ((struct sblock *)); #define CHECK_STRING_BYTES(S) STRING_BYTES (S) /* Like GC_STRING_BYTES, but with debugging check. */ int string_bytes (s) struct Lisp_String *s; { int nbytes = (s->size_byte < 0 ? s->size & ~ARRAY_MARK_FLAG : s->size_byte); if (!PURE_POINTER_P (s) && s->data && nbytes != SDATA_NBYTES (SDATA_OF_STRING (s))) abort (); return nbytes; } /* Check validity of Lisp strings' string_bytes member in B. */ void check_sblock (b) struct sblock *b; { struct sdata *from, *end, *from_end; end = b->next_free; for (from = &b->first_data; from < end; from = from_end) { /* Compute the next FROM here because copying below may overwrite data we need to compute it. */ int nbytes; /* Check that the string size recorded in the string is the same as the one recorded in the sdata structure. */ if (from->string) CHECK_STRING_BYTES (from->string); if (from->string) nbytes = GC_STRING_BYTES (from->string); else nbytes = SDATA_NBYTES (from); nbytes = SDATA_SIZE (nbytes); from_end = (struct sdata *) ((char *) from + nbytes + GC_STRING_EXTRA); } } /* Check validity of Lisp strings' string_bytes member. ALL_P non-zero means check all strings, otherwise check only most recently allocated strings. Used for hunting a bug. */ void check_string_bytes (all_p) int all_p; { if (all_p) { struct sblock *b; for (b = large_sblocks; b; b = b->next) { struct Lisp_String *s = b->first_data.string; if (s) CHECK_STRING_BYTES (s); } for (b = oldest_sblock; b; b = b->next) check_sblock (b); } else check_sblock (current_sblock); } #endif /* GC_CHECK_STRING_BYTES */ #ifdef GC_CHECK_STRING_FREE_LIST /* Walk through the string free list looking for bogus next pointers. This may catch buffer overrun from a previous string. */ static void check_string_free_list () { struct Lisp_String *s; /* Pop a Lisp_String off the free-list. */ s = string_free_list; while (s != NULL) { if ((unsigned)s < 1024) abort(); s = NEXT_FREE_LISP_STRING (s); } } #else #define check_string_free_list() #endif /* Return a new Lisp_String. */ static struct Lisp_String * allocate_string () { struct Lisp_String *s; /* eassert (!handling_signal); */ #ifndef SYNC_INPUT BLOCK_INPUT; #endif /* If the free-list is empty, allocate a new string_block, and add all the Lisp_Strings in it to the free-list. */ if (string_free_list == NULL) { struct string_block *b; int i; b = (struct string_block *) lisp_malloc (sizeof *b, MEM_TYPE_STRING); bzero (b, sizeof *b); b->next = string_blocks; string_blocks = b; ++n_string_blocks; for (i = STRING_BLOCK_SIZE - 1; i >= 0; --i) { s = b->strings + i; NEXT_FREE_LISP_STRING (s) = string_free_list; string_free_list = s; } total_free_strings += STRING_BLOCK_SIZE; } check_string_free_list (); /* Pop a Lisp_String off the free-list. */ s = string_free_list; string_free_list = NEXT_FREE_LISP_STRING (s); #ifndef SYNC_INPUT UNBLOCK_INPUT; #endif /* Probably not strictly necessary, but play it safe. */ bzero (s, sizeof *s); --total_free_strings; ++total_strings; ++strings_consed; consing_since_gc += sizeof *s; #ifdef GC_CHECK_STRING_BYTES if (!noninteractive #ifdef MAC_OS8 && current_sblock #endif ) { if (++check_string_bytes_count == 200) { check_string_bytes_count = 0; check_string_bytes (1); } else check_string_bytes (0); } #endif /* GC_CHECK_STRING_BYTES */ return s; } /* Set up Lisp_String S for holding NCHARS characters, NBYTES bytes, plus a NUL byte at the end. Allocate an sdata structure for S, and set S->data to its `u.data' member. Store a NUL byte at the end of S->data. Set S->size to NCHARS and S->size_byte to NBYTES. Free S->data if it was initially non-null. */ void allocate_string_data (s, nchars, nbytes) struct Lisp_String *s; int nchars, nbytes; { struct sdata *data, *old_data; struct sblock *b; int needed, old_nbytes; /* Determine the number of bytes needed to store NBYTES bytes of string data. */ needed = SDATA_SIZE (nbytes); old_data = s->data ? SDATA_OF_STRING (s) : NULL; old_nbytes = GC_STRING_BYTES (s); #ifndef SYNC_INPUT BLOCK_INPUT; #endif if (nbytes > LARGE_STRING_BYTES) { size_t size = sizeof *b - sizeof (struct sdata) + needed; #ifdef DOUG_LEA_MALLOC /* Prevent mmap'ing the chunk. Lisp data may not be mmap'ed because mapped region contents are not preserved in a dumped Emacs. In case you think of allowing it in a dumped Emacs at the cost of not being able to re-dump, there's another reason: mmap'ed data typically have an address towards the top of the address space, which won't fit into an EMACS_INT (at least on 32-bit systems with the current tagging scheme). --fx */ BLOCK_INPUT; mallopt (M_MMAP_MAX, 0); UNBLOCK_INPUT; #endif b = (struct sblock *) lisp_malloc (size + GC_STRING_EXTRA, MEM_TYPE_NON_LISP); #ifdef DOUG_LEA_MALLOC /* Back to a reasonable maximum of mmap'ed areas. */ BLOCK_INPUT; mallopt (M_MMAP_MAX, MMAP_MAX_AREAS); UNBLOCK_INPUT; #endif b->next_free = &b->first_data; b->first_data.string = NULL; b->next = large_sblocks; large_sblocks = b; } else if (current_sblock == NULL || (((char *) current_sblock + SBLOCK_SIZE - (char *) current_sblock->next_free) < (needed + GC_STRING_EXTRA))) { /* Not enough room in the current sblock. */ b = (struct sblock *) lisp_malloc (SBLOCK_SIZE, MEM_TYPE_NON_LISP); b->next_free = &b->first_data; b->first_data.string = NULL; b->next = NULL; if (current_sblock) current_sblock->next = b; else oldest_sblock = b; current_sblock = b; } else b = current_sblock; data = b->next_free; b->next_free = (struct sdata *) ((char *) data + needed + GC_STRING_EXTRA); #ifndef SYNC_INPUT UNBLOCK_INPUT; #endif data->string = s; s->data = SDATA_DATA (data); #ifdef GC_CHECK_STRING_BYTES SDATA_NBYTES (data) = nbytes; #endif s->size = nchars; s->size_byte = nbytes; s->data[nbytes] = '\0'; #ifdef GC_CHECK_STRING_OVERRUN bcopy (string_overrun_cookie, (char *) data + needed, GC_STRING_OVERRUN_COOKIE_SIZE); #endif /* If S had already data assigned, mark that as free by setting its string back-pointer to null, and recording the size of the data in it. */ if (old_data) { SDATA_NBYTES (old_data) = old_nbytes; old_data->string = NULL; } consing_since_gc += needed; } /* Sweep and compact strings. */ static void sweep_strings () { struct string_block *b, *next; struct string_block *live_blocks = NULL; string_free_list = NULL; total_strings = total_free_strings = 0; total_string_size = 0; /* Scan strings_blocks, free Lisp_Strings that aren't marked. */ for (b = string_blocks; b; b = next) { int i, nfree = 0; struct Lisp_String *free_list_before = string_free_list; next = b->next; for (i = 0; i < STRING_BLOCK_SIZE; ++i) { struct Lisp_String *s = b->strings + i; if (s->data) { /* String was not on free-list before. */ if (STRING_MARKED_P (s)) { /* String is live; unmark it and its intervals. */ UNMARK_STRING (s); if (!NULL_INTERVAL_P (s->intervals)) UNMARK_BALANCE_INTERVALS (s->intervals); ++total_strings; total_string_size += STRING_BYTES (s); } else { /* String is dead. Put it on the free-list. */ struct sdata *data = SDATA_OF_STRING (s); /* Save the size of S in its sdata so that we know how large that is. Reset the sdata's string back-pointer so that we know it's free. */ #ifdef GC_CHECK_STRING_BYTES if (GC_STRING_BYTES (s) != SDATA_NBYTES (data)) abort (); #else data->u.nbytes = GC_STRING_BYTES (s); #endif data->string = NULL; /* Reset the strings's `data' member so that we know it's free. */ s->data = NULL; /* Put the string on the free-list. */ NEXT_FREE_LISP_STRING (s) = string_free_list; string_free_list = s; ++nfree; } } else { /* S was on the free-list before. Put it there again. */ NEXT_FREE_LISP_STRING (s) = string_free_list; string_free_list = s; ++nfree; } } /* Free blocks that contain free Lisp_Strings only, except the first two of them. */ if (nfree == STRING_BLOCK_SIZE && total_free_strings > STRING_BLOCK_SIZE) { lisp_free (b); --n_string_blocks; string_free_list = free_list_before; } else { total_free_strings += nfree; b->next = live_blocks; live_blocks = b; } } check_string_free_list (); string_blocks = live_blocks; free_large_strings (); compact_small_strings (); check_string_free_list (); } /* Free dead large strings. */ static void free_large_strings () { struct sblock *b, *next; struct sblock *live_blocks = NULL; for (b = large_sblocks; b; b = next) { next = b->next; if (b->first_data.string == NULL) lisp_free (b); else { b->next = live_blocks; live_blocks = b; } } large_sblocks = live_blocks; } /* Compact data of small strings. Free sblocks that don't contain data of live strings after compaction. */ static void compact_small_strings () { struct sblock *b, *tb, *next; struct sdata *from, *to, *end, *tb_end; struct sdata *to_end, *from_end; /* TB is the sblock we copy to, TO is the sdata within TB we copy to, and TB_END is the end of TB. */ tb = oldest_sblock; tb_end = (struct sdata *) ((char *) tb + SBLOCK_SIZE); to = &tb->first_data; /* Step through the blocks from the oldest to the youngest. We expect that old blocks will stabilize over time, so that less copying will happen this way. */ for (b = oldest_sblock; b; b = b->next) { end = b->next_free; xassert ((char *) end <= (char *) b + SBLOCK_SIZE); for (from = &b->first_data; from < end; from = from_end) { /* Compute the next FROM here because copying below may overwrite data we need to compute it. */ int nbytes; #ifdef GC_CHECK_STRING_BYTES /* Check that the string size recorded in the string is the same as the one recorded in the sdata structure. */ if (from->string && GC_STRING_BYTES (from->string) != SDATA_NBYTES (from)) abort (); #endif /* GC_CHECK_STRING_BYTES */ if (from->string) nbytes = GC_STRING_BYTES (from->string); else nbytes = SDATA_NBYTES (from); if (nbytes > LARGE_STRING_BYTES) abort (); nbytes = SDATA_SIZE (nbytes); from_end = (struct sdata *) ((char *) from + nbytes + GC_STRING_EXTRA); #ifdef GC_CHECK_STRING_OVERRUN if (bcmp (string_overrun_cookie, ((char *) from_end) - GC_STRING_OVERRUN_COOKIE_SIZE, GC_STRING_OVERRUN_COOKIE_SIZE)) abort (); #endif /* FROM->string non-null means it's alive. Copy its data. */ if (from->string) { /* If TB is full, proceed with the next sblock. */ to_end = (struct sdata *) ((char *) to + nbytes + GC_STRING_EXTRA); if (to_end > tb_end) { tb->next_free = to; tb = tb->next; tb_end = (struct sdata *) ((char *) tb + SBLOCK_SIZE); to = &tb->first_data; to_end = (struct sdata *) ((char *) to + nbytes + GC_STRING_EXTRA); } /* Copy, and update the string's `data' pointer. */ if (from != to) { xassert (tb != b || to <= from); safe_bcopy ((char *) from, (char *) to, nbytes + GC_STRING_EXTRA); to->string->data = SDATA_DATA (to); } /* Advance past the sdata we copied to. */ to = to_end; } } } /* The rest of the sblocks following TB don't contain live data, so we can free them. */ for (b = tb->next; b; b = next) { next = b->next; lisp_free (b); } tb->next_free = to; tb->next = NULL; current_sblock = tb; } DEFUN ("make-string", Fmake_string, Smake_string, 2, 2, 0, doc: /* Return a newly created string of length LENGTH, with INIT in each element. LENGTH must be an integer. INIT must be an integer that represents a character. */) (length, init) Lisp_Object length, init; { register Lisp_Object val; register unsigned char *p, *end; int c, nbytes; CHECK_NATNUM (length); CHECK_NUMBER (init); c = XINT (init); if (SINGLE_BYTE_CHAR_P (c)) { nbytes = XINT (length); val = make_uninit_string (nbytes); p = SDATA (val); end = p + SCHARS (val); while (p != end) *p++ = c; } else { unsigned char str[MAX_MULTIBYTE_LENGTH]; int len = CHAR_STRING (c, str); nbytes = len * XINT (length); val = make_uninit_multibyte_string (XINT (length), nbytes); p = SDATA (val); end = p + nbytes; while (p != end) { bcopy (str, p, len); p += len; } } *p = 0; return val; } DEFUN ("make-bool-vector", Fmake_bool_vector, Smake_bool_vector, 2, 2, 0, doc: /* Return a new bool-vector of length LENGTH, using INIT for each element. LENGTH must be a number. INIT matters only in whether it is t or nil. */) (length, init) Lisp_Object length, init; { register Lisp_Object val; struct Lisp_Bool_Vector *p; int real_init, i; int length_in_chars, length_in_elts, bits_per_value; CHECK_NATNUM (length); bits_per_value = sizeof (EMACS_INT) * BOOL_VECTOR_BITS_PER_CHAR; length_in_elts = (XFASTINT (length) + bits_per_value - 1) / bits_per_value; length_in_chars = ((XFASTINT (length) + BOOL_VECTOR_BITS_PER_CHAR - 1) / BOOL_VECTOR_BITS_PER_CHAR); /* We must allocate one more elements than LENGTH_IN_ELTS for the slot `size' of the struct Lisp_Bool_Vector. */ val = Fmake_vector (make_number (length_in_elts + 1), Qnil); p = XBOOL_VECTOR (val); /* Get rid of any bits that would cause confusion. */ p->vector_size = 0; XSETBOOL_VECTOR (val, p); p->size = XFASTINT (length); real_init = (NILP (init) ? 0 : -1); for (i = 0; i < length_in_chars ; i++) p->data[i] = real_init; /* Clear the extraneous bits in the last byte. */ if (XINT (length) != length_in_chars * BOOL_VECTOR_BITS_PER_CHAR) XBOOL_VECTOR (val)->data[length_in_chars - 1] &= (1 << (XINT (length) % BOOL_VECTOR_BITS_PER_CHAR)) - 1; return val; } /* Make a string from NBYTES bytes at CONTENTS, and compute the number of characters from the contents. This string may be unibyte or multibyte, depending on the contents. */ Lisp_Object make_string (contents, nbytes) const char *contents; int nbytes; { register Lisp_Object val; int nchars, multibyte_nbytes; parse_str_as_multibyte (contents, nbytes, &nchars, &multibyte_nbytes); if (nbytes == nchars || nbytes != multibyte_nbytes) /* CONTENTS contains no multibyte sequences or contains an invalid multibyte sequence. We must make unibyte string. */ val = make_unibyte_string (contents, nbytes); else val = make_multibyte_string (contents, nchars, nbytes); return val; } /* Make an unibyte string from LENGTH bytes at CONTENTS. */ Lisp_Object make_unibyte_string (contents, length) const char *contents; int length; { register Lisp_Object val; val = make_uninit_string (length); bcopy (contents, SDATA (val), length); STRING_SET_UNIBYTE (val); return val; } /* Make a multibyte string from NCHARS characters occupying NBYTES bytes at CONTENTS. */ Lisp_Object make_multibyte_string (contents, nchars, nbytes) const char *contents; int nchars, nbytes; { register Lisp_Object val; val = make_uninit_multibyte_string (nchars, nbytes); bcopy (contents, SDATA (val), nbytes); return val; } /* Make a string from NCHARS characters occupying NBYTES bytes at CONTENTS. It is a multibyte string if NBYTES != NCHARS. */ Lisp_Object make_string_from_bytes (contents, nchars, nbytes) const char *contents; int nchars, nbytes; { register Lisp_Object val; val = make_uninit_multibyte_string (nchars, nbytes); bcopy (contents, SDATA (val), nbytes); if (SBYTES (val) == SCHARS (val)) STRING_SET_UNIBYTE (val); return val; } /* Make a string from NCHARS characters occupying NBYTES bytes at CONTENTS. The argument MULTIBYTE controls whether to label the string as multibyte. If NCHARS is negative, it counts the number of characters by itself. */ Lisp_Object make_specified_string (contents, nchars, nbytes, multibyte) const char *contents; int nchars, nbytes; int multibyte; { register Lisp_Object val; if (nchars < 0) { if (multibyte) nchars = multibyte_chars_in_text (contents, nbytes); else nchars = nbytes; } val = make_uninit_multibyte_string (nchars, nbytes); bcopy (contents, SDATA (val), nbytes); if (!multibyte) STRING_SET_UNIBYTE (val); return val; } /* Make a string from the data at STR, treating it as multibyte if the data warrants. */ Lisp_Object build_string (str) const char *str; { return make_string (str, strlen (str)); } /* Return an unibyte Lisp_String set up to hold LENGTH characters occupying LENGTH bytes. */ Lisp_Object make_uninit_string (length) int length; { Lisp_Object val; val = make_uninit_multibyte_string (length, length); STRING_SET_UNIBYTE (val); return val; } /* Return a multibyte Lisp_String set up to hold NCHARS characters which occupy NBYTES bytes. */ Lisp_Object make_uninit_multibyte_string (nchars, nbytes) int nchars, nbytes; { Lisp_Object string; struct Lisp_String *s; if (nchars < 0) abort (); s = allocate_string (); allocate_string_data (s, nchars, nbytes); XSETSTRING (string, s); string_chars_consed += nbytes; return string; } /*********************************************************************** Float Allocation ***********************************************************************/ /* We store float cells inside of float_blocks, allocating a new float_block with malloc whenever necessary. Float cells reclaimed by GC are put on a free list to be reallocated before allocating any new float cells from the latest float_block. */ #define FLOAT_BLOCK_SIZE \ (((BLOCK_BYTES - sizeof (struct float_block *) \ /* The compiler might add padding at the end. */ \ - (sizeof (struct Lisp_Float) - sizeof (int))) * CHAR_BIT) \ / (sizeof (struct Lisp_Float) * CHAR_BIT + 1)) #define GETMARKBIT(block,n) \ (((block)->gcmarkbits[(n) / (sizeof(int) * CHAR_BIT)] \ >> ((n) % (sizeof(int) * CHAR_BIT))) \ & 1) #define SETMARKBIT(block,n) \ (block)->gcmarkbits[(n) / (sizeof(int) * CHAR_BIT)] \ |= 1 << ((n) % (sizeof(int) * CHAR_BIT)) #define UNSETMARKBIT(block,n) \ (block)->gcmarkbits[(n) / (sizeof(int) * CHAR_BIT)] \ &= ~(1 << ((n) % (sizeof(int) * CHAR_BIT))) #define FLOAT_BLOCK(fptr) \ ((struct float_block *)(((EMACS_UINT)(fptr)) & ~(BLOCK_ALIGN - 1))) #define FLOAT_INDEX(fptr) \ ((((EMACS_UINT)(fptr)) & (BLOCK_ALIGN - 1)) / sizeof (struct Lisp_Float)) struct float_block { /* Place `floats' at the beginning, to ease up FLOAT_INDEX's job. */ struct Lisp_Float floats[FLOAT_BLOCK_SIZE]; int gcmarkbits[1 + FLOAT_BLOCK_SIZE / (sizeof(int) * CHAR_BIT)]; struct float_block *next; }; #define FLOAT_MARKED_P(fptr) \ GETMARKBIT (FLOAT_BLOCK (fptr), FLOAT_INDEX ((fptr))) #define FLOAT_MARK(fptr) \ SETMARKBIT (FLOAT_BLOCK (fptr), FLOAT_INDEX ((fptr))) #define FLOAT_UNMARK(fptr) \ UNSETMARKBIT (FLOAT_BLOCK (fptr), FLOAT_INDEX ((fptr))) /* Current float_block. */ struct float_block *float_block; /* Index of first unused Lisp_Float in the current float_block. */ int float_block_index; /* Total number of float blocks now in use. */ int n_float_blocks; /* Free-list of Lisp_Floats. */ struct Lisp_Float *float_free_list; /* Initialize float allocation. */ void init_float () { float_block = NULL; float_block_index = FLOAT_BLOCK_SIZE; /* Force alloc of new float_block. */ float_free_list = 0; n_float_blocks = 0; } /* Explicitly free a float cell by putting it on the free-list. */ void free_float (ptr) struct Lisp_Float *ptr; { ptr->u.chain = float_free_list; float_free_list = ptr; } /* Return a new float object with value FLOAT_VALUE. */ Lisp_Object make_float (float_value) double float_value; { register Lisp_Object val; /* eassert (!handling_signal); */ #ifndef SYNC_INPUT BLOCK_INPUT; #endif if (float_free_list) { /* We use the data field for chaining the free list so that we won't use the same field that has the mark bit. */ XSETFLOAT (val, float_free_list); float_free_list = float_free_list->u.chain; } else { if (float_block_index == FLOAT_BLOCK_SIZE) { register struct float_block *new; new = (struct float_block *) lisp_align_malloc (sizeof *new, MEM_TYPE_FLOAT); new->next = float_block; bzero ((char *) new->gcmarkbits, sizeof new->gcmarkbits); float_block = new; float_block_index = 0; n_float_blocks++; } XSETFLOAT (val, &float_block->floats[float_block_index]); float_block_index++; } #ifndef SYNC_INPUT UNBLOCK_INPUT; #endif XFLOAT_DATA (val) = float_value; eassert (!FLOAT_MARKED_P (XFLOAT (val))); consing_since_gc += sizeof (struct Lisp_Float); floats_consed++; return val; } /*********************************************************************** Cons Allocation ***********************************************************************/ /* We store cons cells inside of cons_blocks, allocating a new cons_block with malloc whenever necessary. Cons cells reclaimed by GC are put on a free list to be reallocated before allocating any new cons cells from the latest cons_block. */ #define CONS_BLOCK_SIZE \ (((BLOCK_BYTES - sizeof (struct cons_block *)) * CHAR_BIT) \ / (sizeof (struct Lisp_Cons) * CHAR_BIT + 1)) #define CONS_BLOCK(fptr) \ ((struct cons_block *)(((EMACS_UINT)(fptr)) & ~(BLOCK_ALIGN - 1))) #define CONS_INDEX(fptr) \ ((((EMACS_UINT)(fptr)) & (BLOCK_ALIGN - 1)) / sizeof (struct Lisp_Cons)) struct cons_block { /* Place `conses' at the beginning, to ease up CONS_INDEX's job. */ struct Lisp_Cons conses[CONS_BLOCK_SIZE]; int gcmarkbits[1 + CONS_BLOCK_SIZE / (sizeof(int) * CHAR_BIT)]; struct cons_block *next; }; #define CONS_MARKED_P(fptr) \ GETMARKBIT (CONS_BLOCK (fptr), CONS_INDEX ((fptr))) #define CONS_MARK(fptr) \ SETMARKBIT (CONS_BLOCK (fptr), CONS_INDEX ((fptr))) #define CONS_UNMARK(fptr) \ UNSETMARKBIT (CONS_BLOCK (fptr), CONS_INDEX ((fptr))) /* Current cons_block. */ struct cons_block *cons_block; /* Index of first unused Lisp_Cons in the current block. */ int cons_block_index; /* Free-list of Lisp_Cons structures. */ struct Lisp_Cons *cons_free_list; /* Total number of cons blocks now in use. */ int n_cons_blocks; /* Initialize cons allocation. */ void init_cons () { cons_block = NULL; cons_block_index = CONS_BLOCK_SIZE; /* Force alloc of new cons_block. */ cons_free_list = 0; n_cons_blocks = 0; } /* Explicitly free a cons cell by putting it on the free-list. */ void free_cons (ptr) struct Lisp_Cons *ptr; { ptr->u.chain = cons_free_list; #if GC_MARK_STACK ptr->car = Vdead; #endif cons_free_list = ptr; } DEFUN ("cons", Fcons, Scons, 2, 2, 0, doc: /* Create a new cons, give it CAR and CDR as components, and return it. */) (car, cdr) Lisp_Object car, cdr; { register Lisp_Object val; /* eassert (!handling_signal); */ #ifndef SYNC_INPUT BLOCK_INPUT; #endif if (cons_free_list) { /* We use the cdr for chaining the free list so that we won't use the same field that has the mark bit. */ XSETCONS (val, cons_free_list); cons_free_list = cons_free_list->u.chain; } else { if (cons_block_index == CONS_BLOCK_SIZE) { register struct cons_block *new; new = (struct cons_block *) lisp_align_malloc (sizeof *new, MEM_TYPE_CONS); bzero ((char *) new->gcmarkbits, sizeof new->gcmarkbits); new->next = cons_block; cons_block = new; cons_block_index = 0; n_cons_blocks++; } XSETCONS (val, &cons_block->conses[cons_block_index]); cons_block_index++; } #ifndef SYNC_INPUT UNBLOCK_INPUT; #endif XSETCAR (val, car); XSETCDR (val, cdr); eassert (!CONS_MARKED_P (XCONS (val))); consing_since_gc += sizeof (struct Lisp_Cons); cons_cells_consed++; return val; } /* Get an error now if there's any junk in the cons free list. */ void check_cons_list () { #ifdef GC_CHECK_CONS_LIST struct Lisp_Cons *tail = cons_free_list; while (tail) tail = tail->u.chain; #endif } /* Make a list of 1, 2, 3, 4 or 5 specified objects. */ Lisp_Object list1 (arg1) Lisp_Object arg1; { return Fcons (arg1, Qnil); } Lisp_Object list2 (arg1, arg2) Lisp_Object arg1, arg2; { return Fcons (arg1, Fcons (arg2, Qnil)); } Lisp_Object list3 (arg1, arg2, arg3) Lisp_Object arg1, arg2, arg3; { return Fcons (arg1, Fcons (arg2, Fcons (arg3, Qnil))); } Lisp_Object list4 (arg1, arg2, arg3, arg4) Lisp_Object arg1, arg2, arg3, arg4; { return Fcons (arg1, Fcons (arg2, Fcons (arg3, Fcons (arg4, Qnil)))); } Lisp_Object list5 (arg1, arg2, arg3, arg4, arg5) Lisp_Object arg1, arg2, arg3, arg4, arg5; { return Fcons (arg1, Fcons (arg2, Fcons (arg3, Fcons (arg4, Fcons (arg5, Qnil))))); } DEFUN ("list", Flist, Slist, 0, MANY, 0, doc: /* Return a newly created list with specified arguments as elements. Any number of arguments, even zero arguments, are allowed. usage: (list &rest OBJECTS) */) (nargs, args) int nargs; register Lisp_Object *args; { register Lisp_Object val; val = Qnil; while (nargs > 0) { nargs--; val = Fcons (args[nargs], val); } return val; } DEFUN ("make-list", Fmake_list, Smake_list, 2, 2, 0, doc: /* Return a newly created list of length LENGTH, with each element being INIT. */) (length, init) register Lisp_Object length, init; { register Lisp_Object val; register int size; CHECK_NATNUM (length); size = XFASTINT (length); val = Qnil; while (size > 0) { val = Fcons (init, val); --size; if (size > 0) { val = Fcons (init, val); --size; if (size > 0) { val = Fcons (init, val); --size; if (size > 0) { val = Fcons (init, val); --size; if (size > 0) { val = Fcons (init, val); --size; } } } } QUIT; } return val; } /*********************************************************************** Vector Allocation ***********************************************************************/ /* Singly-linked list of all vectors. */ struct Lisp_Vector *all_vectors; /* Total number of vector-like objects now in use. */ int n_vectors; /* Value is a pointer to a newly allocated Lisp_Vector structure with room for LEN Lisp_Objects. */ static struct Lisp_Vector * allocate_vectorlike (len, type) EMACS_INT len; enum mem_type type; { struct Lisp_Vector *p; size_t nbytes; #ifdef DOUG_LEA_MALLOC /* Prevent mmap'ing the chunk. Lisp data may not be mmap'ed because mapped region contents are not preserved in a dumped Emacs. */ BLOCK_INPUT; mallopt (M_MMAP_MAX, 0); UNBLOCK_INPUT; #endif /* This gets triggered by code which I haven't bothered to fix. --Stef */ /* eassert (!handling_signal); */ nbytes = sizeof *p + (len - 1) * sizeof p->contents[0]; p = (struct Lisp_Vector *) lisp_malloc (nbytes, type); #ifdef DOUG_LEA_MALLOC /* Back to a reasonable maximum of mmap'ed areas. */ BLOCK_INPUT; mallopt (M_MMAP_MAX, MMAP_MAX_AREAS); UNBLOCK_INPUT; #endif consing_since_gc += nbytes; vector_cells_consed += len; #ifndef SYNC_INPUT BLOCK_INPUT; #endif p->next = all_vectors; all_vectors = p; #ifndef SYNC_INPUT UNBLOCK_INPUT; #endif ++n_vectors; return p; } /* Allocate a vector with NSLOTS slots. */ struct Lisp_Vector * allocate_vector (nslots) EMACS_INT nslots; { struct Lisp_Vector *v = allocate_vectorlike (nslots, MEM_TYPE_VECTOR); v->size = nslots; return v; } /* Allocate other vector-like structures. */ struct Lisp_Hash_Table * allocate_hash_table () { EMACS_INT len = VECSIZE (struct Lisp_Hash_Table); struct Lisp_Vector *v = allocate_vectorlike (len, MEM_TYPE_HASH_TABLE); EMACS_INT i; v->size = len; for (i = 0; i < len; ++i) v->contents[i] = Qnil; return (struct Lisp_Hash_Table *) v; } struct window * allocate_window () { EMACS_INT len = VECSIZE (struct window); struct Lisp_Vector *v = allocate_vectorlike (len, MEM_TYPE_WINDOW); EMACS_INT i; for (i = 0; i < len; ++i) v->contents[i] = Qnil; v->size = len; return (struct window *) v; } struct frame * allocate_frame () { EMACS_INT len = VECSIZE (struct frame); struct Lisp_Vector *v = allocate_vectorlike (len, MEM_TYPE_FRAME); EMACS_INT i; for (i = 0; i < len; ++i) v->contents[i] = make_number (0); v->size = len; return (struct frame *) v; } struct Lisp_Process * allocate_process () { /* Memory-footprint of the object in nb of Lisp_Object fields. */ EMACS_INT memlen = VECSIZE (struct Lisp_Process); /* Size if we only count the actual Lisp_Object fields (which need to be traced by the GC). */ EMACS_INT lisplen = PSEUDOVECSIZE (struct Lisp_Process, pid); struct Lisp_Vector *v = allocate_vectorlike (memlen, MEM_TYPE_PROCESS); EMACS_INT i; for (i = 0; i < lisplen; ++i) v->contents[i] = Qnil; v->size = lisplen; return (struct Lisp_Process *) v; } struct Lisp_Vector * allocate_other_vector (len) EMACS_INT len; { struct Lisp_Vector *v = allocate_vectorlike (len, MEM_TYPE_VECTOR); EMACS_INT i; for (i = 0; i < len; ++i) v->contents[i] = Qnil; v->size = len; return v; } DEFUN ("make-vector", Fmake_vector, Smake_vector, 2, 2, 0, doc: /* Return a newly created vector of length LENGTH, with each element being INIT. See also the function `vector'. */) (length, init) register Lisp_Object length, init; { Lisp_Object vector; register EMACS_INT sizei; register int index; register struct Lisp_Vector *p; CHECK_NATNUM (length); sizei = XFASTINT (length); p = allocate_vector (sizei); for (index = 0; index < sizei; index++) p->contents[index] = init; XSETVECTOR (vector, p); return vector; } DEFUN ("make-char-table", Fmake_char_table, Smake_char_table, 1, 2, 0, doc: /* Return a newly created char-table, with purpose PURPOSE. Each element is initialized to INIT, which defaults to nil. PURPOSE should be a symbol which has a `char-table-extra-slots' property. The property's value should be an integer between 0 and 10. */) (purpose, init) register Lisp_Object purpose, init; { Lisp_Object vector; Lisp_Object n; CHECK_SYMBOL (purpose); n = Fget (purpose, Qchar_table_extra_slots); CHECK_NUMBER (n); if (XINT (n) < 0 || XINT (n) > 10) args_out_of_range (n, Qnil); /* Add 2 to the size for the defalt and parent slots. */ vector = Fmake_vector (make_number (CHAR_TABLE_STANDARD_SLOTS + XINT (n)), init); XCHAR_TABLE (vector)->top = Qt; XCHAR_TABLE (vector)->parent = Qnil; XCHAR_TABLE (vector)->purpose = purpose; XSETCHAR_TABLE (vector, XCHAR_TABLE (vector)); return vector; } /* Return a newly created sub char table with slots initialized by INIT. Since a sub char table does not appear as a top level Emacs Lisp object, we don't need a Lisp interface to make it. */ Lisp_Object make_sub_char_table (init) Lisp_Object init; { Lisp_Object vector = Fmake_vector (make_number (SUB_CHAR_TABLE_STANDARD_SLOTS), init); XCHAR_TABLE (vector)->top = Qnil; XCHAR_TABLE (vector)->defalt = Qnil; XSETCHAR_TABLE (vector, XCHAR_TABLE (vector)); return vector; } DEFUN ("vector", Fvector, Svector, 0, MANY, 0, doc: /* Return a newly created vector with specified arguments as elements. Any number of arguments, even zero arguments, are allowed. usage: (vector &rest OBJECTS) */) (nargs, args) register int nargs; Lisp_Object *args; { register Lisp_Object len, val; register int index; register struct Lisp_Vector *p; XSETFASTINT (len, nargs); val = Fmake_vector (len, Qnil); p = XVECTOR (val); for (index = 0; index < nargs; index++) p->contents[index] = args[index]; return val; } DEFUN ("make-byte-code", Fmake_byte_code, Smake_byte_code, 4, MANY, 0, doc: /* Create a byte-code object with specified arguments as elements. The arguments should be the arglist, bytecode-string, constant vector, stack size, (optional) doc string, and (optional) interactive spec. The first four arguments are required; at most six have any significance. usage: (make-byte-code ARGLIST BYTE-CODE CONSTANTS DEPTH &optional DOCSTRING INTERACTIVE-SPEC &rest ELEMENTS) */) (nargs, args) register int nargs; Lisp_Object *args; { register Lisp_Object len, val; register int index; register struct Lisp_Vector *p; XSETFASTINT (len, nargs); if (!NILP (Vpurify_flag)) val = make_pure_vector ((EMACS_INT) nargs); else val = Fmake_vector (len, Qnil); if (STRINGP (args[1]) && STRING_MULTIBYTE (args[1])) /* BYTECODE-STRING must have been produced by Emacs 20.2 or the earlier because they produced a raw 8-bit string for byte-code and now such a byte-code string is loaded as multibyte while raw 8-bit characters converted to multibyte form. Thus, now we must convert them back to the original unibyte form. */ args[1] = Fstring_as_unibyte (args[1]); p = XVECTOR (val); for (index = 0; index < nargs; index++) { if (!NILP (Vpurify_flag)) args[index] = Fpurecopy (args[index]); p->contents[index] = args[index]; } XSETCOMPILED (val, p); return val; } /*********************************************************************** Symbol Allocation ***********************************************************************/ /* Each symbol_block is just under 1020 bytes long, since malloc really allocates in units of powers of two and uses 4 bytes for its own overhead. */ #define SYMBOL_BLOCK_SIZE \ ((1020 - sizeof (struct symbol_block *)) / sizeof (struct Lisp_Symbol)) struct symbol_block { /* Place `symbols' first, to preserve alignment. */ struct Lisp_Symbol symbols[SYMBOL_BLOCK_SIZE]; struct symbol_block *next; }; /* Current symbol block and index of first unused Lisp_Symbol structure in it. */ struct symbol_block *symbol_block; int symbol_block_index; /* List of free symbols. */ struct Lisp_Symbol *symbol_free_list; /* Total number of symbol blocks now in use. */ int n_symbol_blocks; /* Initialize symbol allocation. */ void init_symbol () { symbol_block = NULL; symbol_block_index = SYMBOL_BLOCK_SIZE; symbol_free_list = 0; n_symbol_blocks = 0; } DEFUN ("make-symbol", Fmake_symbol, Smake_symbol, 1, 1, 0, doc: /* Return a newly allocated uninterned symbol whose name is NAME. Its value and function definition are void, and its property list is nil. */) (name) Lisp_Object name; { register Lisp_Object val; register struct Lisp_Symbol *p; CHECK_STRING (name); /* eassert (!handling_signal); */ #ifndef SYNC_INPUT BLOCK_INPUT; #endif if (symbol_free_list) { XSETSYMBOL (val, symbol_free_list); symbol_free_list = symbol_free_list->next; } else { if (symbol_block_index == SYMBOL_BLOCK_SIZE) { struct symbol_block *new; new = (struct symbol_block *) lisp_malloc (sizeof *new, MEM_TYPE_SYMBOL); new->next = symbol_block; symbol_block = new; symbol_block_index = 0; n_symbol_blocks++; } XSETSYMBOL (val, &symbol_block->symbols[symbol_block_index]); symbol_block_index++; } #ifndef SYNC_INPUT UNBLOCK_INPUT; #endif p = XSYMBOL (val); p->xname = name; p->plist = Qnil; p->value = Qunbound; p->function = Qunbound; p->next = NULL; p->gcmarkbit = 0; p->interned = SYMBOL_UNINTERNED; p->constant = 0; p->indirect_variable = 0; consing_since_gc += sizeof (struct Lisp_Symbol); symbols_consed++; return val; } /*********************************************************************** Marker (Misc) Allocation ***********************************************************************/ /* Allocation of markers and other objects that share that structure. Works like allocation of conses. */ #define MARKER_BLOCK_SIZE \ ((1020 - sizeof (struct marker_block *)) / sizeof (union Lisp_Misc)) struct marker_block { /* Place `markers' first, to preserve alignment. */ union Lisp_Misc markers[MARKER_BLOCK_SIZE]; struct marker_block *next; }; struct marker_block *marker_block; int marker_block_index; union Lisp_Misc *marker_free_list; /* Total number of marker blocks now in use. */ int n_marker_blocks; void init_marker () { marker_block = NULL; marker_block_index = MARKER_BLOCK_SIZE; marker_free_list = 0; n_marker_blocks = 0; } /* Return a newly allocated Lisp_Misc object, with no substructure. */ Lisp_Object allocate_misc () { Lisp_Object val; /* eassert (!handling_signal); */ #ifndef SYNC_INPUT BLOCK_INPUT; #endif if (marker_free_list) { XSETMISC (val, marker_free_list); marker_free_list = marker_free_list->u_free.chain; } else { if (marker_block_index == MARKER_BLOCK_SIZE) { struct marker_block *new; new = (struct marker_block *) lisp_malloc (sizeof *new, MEM_TYPE_MISC); new->next = marker_block; marker_block = new; marker_block_index = 0; n_marker_blocks++; total_free_markers += MARKER_BLOCK_SIZE; } XSETMISC (val, &marker_block->markers[marker_block_index]); marker_block_index++; } #ifndef SYNC_INPUT UNBLOCK_INPUT; #endif --total_free_markers; consing_since_gc += sizeof (union Lisp_Misc); misc_objects_consed++; XMARKER (val)->gcmarkbit = 0; return val; } /* Free a Lisp_Misc object */ void free_misc (misc) Lisp_Object misc; { XMISC (misc)->u_marker.type = Lisp_Misc_Free; XMISC (misc)->u_free.chain = marker_free_list; marker_free_list = XMISC (misc); total_free_markers++; } /* Return a Lisp_Misc_Save_Value object containing POINTER and INTEGER. This is used to package C values to call record_unwind_protect. The unwind function can get the C values back using XSAVE_VALUE. */ Lisp_Object make_save_value (pointer, integer) void *pointer; int integer; { register Lisp_Object val; register struct Lisp_Save_Value *p; val = allocate_misc (); XMISCTYPE (val) = Lisp_Misc_Save_Value; p = XSAVE_VALUE (val); p->pointer = pointer; p->integer = integer; p->dogc = 0; return val; } DEFUN ("make-marker", Fmake_marker, Smake_marker, 0, 0, 0, doc: /* Return a newly allocated marker which does not point at any place. */) () { register Lisp_Object val; register struct Lisp_Marker *p; val = allocate_misc (); XMISCTYPE (val) = Lisp_Misc_Marker; p = XMARKER (val); p->buffer = 0; p->bytepos = 0; p->charpos = 0; p->next = NULL; p->insertion_type = 0; return val; } /* Put MARKER back on the free list after using it temporarily. */ void free_marker (marker) Lisp_Object marker; { unchain_marker (XMARKER (marker)); free_misc (marker); } /* Return a newly created vector or string with specified arguments as elements. If all the arguments are characters that can fit in a string of events, make a string; otherwise, make a vector. Any number of arguments, even zero arguments, are allowed. */ Lisp_Object make_event_array (nargs, args) register int nargs; Lisp_Object *args; { int i; for (i = 0; i < nargs; i++) /* The things that fit in a string are characters that are in 0...127, after discarding the meta bit and all the bits above it. */ if (!INTEGERP (args[i]) || (XUINT (args[i]) & ~(-CHAR_META)) >= 0200) return Fvector (nargs, args); /* Since the loop exited, we know that all the things in it are characters, so we can make a string. */ { Lisp_Object result; result = Fmake_string (make_number (nargs), make_number (0)); for (i = 0; i < nargs; i++) { SSET (result, i, XINT (args[i])); /* Move the meta bit to the right place for a string char. */ if (XINT (args[i]) & CHAR_META) SSET (result, i, SREF (result, i) | 0x80); } return result; } } /************************************************************************ Memory Full Handling ************************************************************************/ /* Called if malloc returns zero. */ void memory_full () { int i; Vmemory_full = Qt; memory_full_cons_threshold = sizeof (struct cons_block); /* The first time we get here, free the spare memory. */ for (i = 0; i < sizeof (spare_memory) / sizeof (char *); i++) if (spare_memory[i]) { if (i == 0) free (spare_memory[i]); else if (i >= 1 && i <= 4) lisp_align_free (spare_memory[i]); else lisp_free (spare_memory[i]); spare_memory[i] = 0; } /* Record the space now used. When it decreases substantially, we can refill the memory reserve. */ #ifndef SYSTEM_MALLOC bytes_used_when_full = BYTES_USED; #endif /* This used to call error, but if we've run out of memory, we could get infinite recursion trying to build the string. */ xsignal (Qnil, Vmemory_signal_data); } /* If we released our reserve (due to running out of memory), and we have a fair amount free once again, try to set aside another reserve in case we run out once more. This is called when a relocatable block is freed in ralloc.c, and also directly from this file, in case we're not using ralloc.c. */ void refill_memory_reserve () { #ifndef SYSTEM_MALLOC if (spare_memory[0] == 0) spare_memory[0] = (char *) malloc ((size_t) SPARE_MEMORY); if (spare_memory[1] == 0) spare_memory[1] = (char *) lisp_align_malloc (sizeof (struct cons_block), MEM_TYPE_CONS); if (spare_memory[2] == 0) spare_memory[2] = (char *) lisp_align_malloc (sizeof (struct cons_block), MEM_TYPE_CONS); if (spare_memory[3] == 0) spare_memory[3] = (char *) lisp_align_malloc (sizeof (struct cons_block), MEM_TYPE_CONS); if (spare_memory[4] == 0) spare_memory[4] = (char *) lisp_align_malloc (sizeof (struct cons_block), MEM_TYPE_CONS); if (spare_memory[5] == 0) spare_memory[5] = (char *) lisp_malloc (sizeof (struct string_block), MEM_TYPE_STRING); if (spare_memory[6] == 0) spare_memory[6] = (char *) lisp_malloc (sizeof (struct string_block), MEM_TYPE_STRING); if (spare_memory[0] && spare_memory[1] && spare_memory[5]) Vmemory_full = Qnil; #endif } /************************************************************************ C Stack Marking ************************************************************************/ #if GC_MARK_STACK || defined GC_MALLOC_CHECK /* Conservative C stack marking requires a method to identify possibly live Lisp objects given a pointer value. We do this by keeping track of blocks of Lisp data that are allocated in a red-black tree (see also the comment of mem_node which is the type of nodes in that tree). Function lisp_malloc adds information for an allocated block to the red-black tree with calls to mem_insert, and function lisp_free removes it with mem_delete. Functions live_string_p etc call mem_find to lookup information about a given pointer in the tree, and use that to determine if the pointer points to a Lisp object or not. */ /* Initialize this part of alloc.c. */ static void mem_init () { mem_z.left = mem_z.right = MEM_NIL; mem_z.parent = NULL; mem_z.color = MEM_BLACK; mem_z.start = mem_z.end = NULL; mem_root = MEM_NIL; } /* Value is a pointer to the mem_node containing START. Value is MEM_NIL if there is no node in the tree containing START. */ static INLINE struct mem_node * mem_find (start) void *start; { struct mem_node *p; if (start < min_heap_address || start > max_heap_address) return MEM_NIL; /* Make the search always successful to speed up the loop below. */ mem_z.start = start; mem_z.end = (char *) start + 1; p = mem_root; while (start < p->start || start >= p->end) p = start < p->start ? p->left : p->right; return p; } /* Insert a new node into the tree for a block of memory with start address START, end address END, and type TYPE. Value is a pointer to the node that was inserted. */ static struct mem_node * mem_insert (start, end, type) void *start, *end; enum mem_type type; { struct mem_node *c, *parent, *x; if (start < min_heap_address) min_heap_address = start; if (end > max_heap_address) max_heap_address = end; /* See where in the tree a node for START belongs. In this particular application, it shouldn't happen that a node is already present. For debugging purposes, let's check that. */ c = mem_root; parent = NULL; #if GC_MARK_STACK != GC_MAKE_GCPROS_NOOPS while (c != MEM_NIL) { if (start >= c->start && start < c->end) abort (); parent = c; c = start < c->start ? c->left : c->right; } #else /* GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS */ while (c != MEM_NIL) { parent = c; c = start < c->start ? c->left : c->right; } #endif /* GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS */ /* Create a new node. */ #ifdef GC_MALLOC_CHECK x = (struct mem_node *) _malloc_internal (sizeof *x); if (x == NULL) abort (); #else x = (struct mem_node *) xmalloc (sizeof *x); #endif x->start = start; x->end = end; x->type = type; x->parent = parent; x->left = x->right = MEM_NIL; x->color = MEM_RED; /* Insert it as child of PARENT or install it as root. */ if (parent) { if (start < parent->start) parent->left = x; else parent->right = x; } else mem_root = x; /* Re-establish red-black tree properties. */ mem_insert_fixup (x); return x; } /* Re-establish the red-black properties of the tree, and thereby balance the tree, after node X has been inserted; X is always red. */ static void mem_insert_fixup (x) struct mem_node *x; { while (x != mem_root && x->parent->color == MEM_RED) { /* X is red and its parent is red. This is a violation of red-black tree property #3. */ if (x->parent == x->parent->parent->left) { /* We're on the left side of our grandparent, and Y is our "uncle". */ struct mem_node *y = x->parent->parent->right; if (y->color == MEM_RED) { /* Uncle and parent are red but should be black because X is red. Change the colors accordingly and proceed with the grandparent. */ x->parent->color = MEM_BLACK; y->color = MEM_BLACK; x->parent->parent->color = MEM_RED; x = x->parent->parent; } else { /* Parent and uncle have different colors; parent is red, uncle is black. */ if (x == x->parent->right) { x = x->parent; mem_rotate_left (x); } x->parent->color = MEM_BLACK; x->parent->parent->color = MEM_RED; mem_rotate_right (x->parent->parent); } } else { /* This is the symmetrical case of above. */ struct mem_node *y = x->parent->parent->left; if (y->color == MEM_RED) { x->parent->color = MEM_BLACK; y->color = MEM_BLACK; x->parent->parent->color = MEM_RED; x = x->parent->parent; } else { if (x == x->parent->left) { x = x->parent; mem_rotate_right (x); } x->parent->color = MEM_BLACK; x->parent->parent->color = MEM_RED; mem_rotate_left (x->parent->parent); } } } /* The root may have been changed to red due to the algorithm. Set it to black so that property #5 is satisfied. */ mem_root->color = MEM_BLACK; } /* (x) (y) / \ / \ a (y) ===> (x) c / \ / \ b c a b */ static void mem_rotate_left (x) struct mem_node *x; { struct mem_node *y; /* Turn y's left sub-tree into x's right sub-tree. */ y = x->right; x->right = y->left; if (y->left != MEM_NIL) y->left->parent = x; /* Y's parent was x's parent. */ if (y != MEM_NIL) y->parent = x->parent; /* Get the parent to point to y instead of x. */ if (x->parent) { if (x == x->parent->left) x->parent->left = y; else x->parent->right = y; } else mem_root = y; /* Put x on y's left. */ y->left = x; if (x != MEM_NIL) x->parent = y; } /* (x) (Y) / \ / \ (y) c ===> a (x) / \ / \ a b b c */ static void mem_rotate_right (x) struct mem_node *x; { struct mem_node *y = x->left; x->left = y->right; if (y->right != MEM_NIL) y->right->parent = x; if (y != MEM_NIL) y->parent = x->parent; if (x->parent) { if (x == x->parent->right) x->parent->right = y; else x->parent->left = y; } else mem_root = y; y->right = x; if (x != MEM_NIL) x->parent = y; } /* Delete node Z from the tree. If Z is null or MEM_NIL, do nothing. */ static void mem_delete (z) struct mem_node *z; { struct mem_node *x, *y; if (!z || z == MEM_NIL) return; if (z->left == MEM_NIL || z->right == MEM_NIL) y = z; else { y = z->right; while (y->left != MEM_NIL) y = y->left; } if (y->left != MEM_NIL) x = y->left; else x = y->right; x->parent = y->parent; if (y->parent) { if (y == y->parent->left) y->parent->left = x; else y->parent->right = x; } else mem_root = x; if (y != z) { z->start = y->start; z->end = y->end; z->type = y->type; } if (y->color == MEM_BLACK) mem_delete_fixup (x); #ifdef GC_MALLOC_CHECK _free_internal (y); #else xfree (y); #endif } /* Re-establish the red-black properties of the tree, after a deletion. */ static void mem_delete_fixup (x) struct mem_node *x; { while (x != mem_root && x->color == MEM_BLACK) { if (x == x->parent->left) { struct mem_node *w = x->parent->right; if (w->color == MEM_RED) { w->color = MEM_BLACK; x->parent->color = MEM_RED; mem_rotate_left (x->parent); w = x->parent->right; } if (w->left->color == MEM_BLACK && w->right->color == MEM_BLACK) { w->color = MEM_RED; x = x->parent; } else { if (w->right->color == MEM_BLACK) { w->left->color = MEM_BLACK; w->color = MEM_RED; mem_rotate_right (w); w = x->parent->right; } w->color = x->parent->color; x->parent->color = MEM_BLACK; w->right->color = MEM_BLACK; mem_rotate_left (x->parent); x = mem_root; } } else { struct mem_node *w = x->parent->left; if (w->color == MEM_RED) { w->color = MEM_BLACK; x->parent->color = MEM_RED; mem_rotate_right (x->parent); w = x->parent->left; } if (w->right->color == MEM_BLACK && w->left->color == MEM_BLACK) { w->color = MEM_RED; x = x->parent; } else { if (w->left->color == MEM_BLACK) { w->right->color = MEM_BLACK; w->color = MEM_RED; mem_rotate_left (w); w = x->parent->left; } w->color = x->parent->color; x->parent->color = MEM_BLACK; w->left->color = MEM_BLACK; mem_rotate_right (x->parent); x = mem_root; } } } x->color = MEM_BLACK; } /* Value is non-zero if P is a pointer to a live Lisp string on the heap. M is a pointer to the mem_block for P. */ static INLINE int live_string_p (m, p) struct mem_node *m; void *p; { if (m->type == MEM_TYPE_STRING) { struct string_block *b = (struct string_block *) m->start; int offset = (char *) p - (char *) &b->strings[0]; /* P must point to the start of a Lisp_String structure, and it must not be on the free-list. */ return (offset >= 0 && offset % sizeof b->strings[0] == 0 && offset < (STRING_BLOCK_SIZE * sizeof b->strings[0]) && ((struct Lisp_String *) p)->data != NULL); } else return 0; } /* Value is non-zero if P is a pointer to a live Lisp cons on the heap. M is a pointer to the mem_block for P. */ static INLINE int live_cons_p (m, p) struct mem_node *m; void *p; { if (m->type == MEM_TYPE_CONS) { struct cons_block *b = (struct cons_block *) m->start; int offset = (char *) p - (char *) &b->conses[0]; /* P must point to the start of a Lisp_Cons, not be one of the unused cells in the current cons block, and not be on the free-list. */ return (offset >= 0 && offset % sizeof b->conses[0] == 0 && offset < (CONS_BLOCK_SIZE * sizeof b->conses[0]) && (b != cons_block || offset / sizeof b->conses[0] < cons_block_index) && !EQ (((struct Lisp_Cons *) p)->car, Vdead)); } else return 0; } /* Value is non-zero if P is a pointer to a live Lisp symbol on the heap. M is a pointer to the mem_block for P. */ static INLINE int live_symbol_p (m, p) struct mem_node *m; void *p; { if (m->type == MEM_TYPE_SYMBOL) { struct symbol_block *b = (struct symbol_block *) m->start; int offset = (char *) p - (char *) &b->symbols[0]; /* P must point to the start of a Lisp_Symbol, not be one of the unused cells in the current symbol block, and not be on the free-list. */ return (offset >= 0 && offset % sizeof b->symbols[0] == 0 && offset < (SYMBOL_BLOCK_SIZE * sizeof b->symbols[0]) && (b != symbol_block || offset / sizeof b->symbols[0] < symbol_block_index) && !EQ (((struct Lisp_Symbol *) p)->function, Vdead)); } else return 0; } /* Value is non-zero if P is a pointer to a live Lisp float on the heap. M is a pointer to the mem_block for P. */ static INLINE int live_float_p (m, p) struct mem_node *m; void *p; { if (m->type == MEM_TYPE_FLOAT) { struct float_block *b = (struct float_block *) m->start; int offset = (char *) p - (char *) &b->floats[0]; /* P must point to the start of a Lisp_Float and not be one of the unused cells in the current float block. */ return (offset >= 0 && offset % sizeof b->floats[0] == 0 && offset < (FLOAT_BLOCK_SIZE * sizeof b->floats[0]) && (b != float_block || offset / sizeof b->floats[0] < float_block_index)); } else return 0; } /* Value is non-zero if P is a pointer to a live Lisp Misc on the heap. M is a pointer to the mem_block for P. */ static INLINE int live_misc_p (m, p) struct mem_node *m; void *p; { if (m->type == MEM_TYPE_MISC) { struct marker_block *b = (struct marker_block *) m->start; int offset = (char *) p - (char *) &b->markers[0]; /* P must point to the start of a Lisp_Misc, not be one of the unused cells in the current misc block, and not be on the free-list. */ return (offset >= 0 && offset % sizeof b->markers[0] == 0 && offset < (MARKER_BLOCK_SIZE * sizeof b->markers[0]) && (b != marker_block || offset / sizeof b->markers[0] < marker_block_index) && ((union Lisp_Misc *) p)->u_marker.type != Lisp_Misc_Free); } else return 0; } /* Value is non-zero if P is a pointer to a live vector-like object. M is a pointer to the mem_block for P. */ static INLINE int live_vector_p (m, p) struct mem_node *m; void *p; { return (p == m->start && m->type >= MEM_TYPE_VECTOR && m->type <= MEM_TYPE_WINDOW); } /* Value is non-zero if P is a pointer to a live buffer. M is a pointer to the mem_block for P. */ static INLINE int live_buffer_p (m, p) struct mem_node *m; void *p; { /* P must point to the start of the block, and the buffer must not have been killed. */ return (m->type == MEM_TYPE_BUFFER && p == m->start && !NILP (((struct buffer *) p)->name)); } #endif /* GC_MARK_STACK || defined GC_MALLOC_CHECK */ #if GC_MARK_STACK #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES /* Array of objects that are kept alive because the C stack contains a pattern that looks like a reference to them . */ #define MAX_ZOMBIES 10 static Lisp_Object zombies[MAX_ZOMBIES]; /* Number of zombie objects. */ static int nzombies; /* Number of garbage collections. */ static int ngcs; /* Average percentage of zombies per collection. */ static double avg_zombies; /* Max. number of live and zombie objects. */ static int max_live, max_zombies; /* Average number of live objects per GC. */ static double avg_live; DEFUN ("gc-status", Fgc_status, Sgc_status, 0, 0, "", doc: /* Show information about live and zombie objects. */) () { Lisp_Object args[8], zombie_list = Qnil; int i; for (i = 0; i < nzombies; i++) zombie_list = Fcons (zombies[i], zombie_list); args[0] = build_string ("%d GCs, avg live/zombies = %.2f/%.2f (%f%%), max %d/%d\nzombies: %S"); args[1] = make_number (ngcs); args[2] = make_float (avg_live); args[3] = make_float (avg_zombies); args[4] = make_float (avg_zombies / avg_live / 100); args[5] = make_number (max_live); args[6] = make_number (max_zombies); args[7] = zombie_list; return Fmessage (8, args); } #endif /* GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES */ /* Mark OBJ if we can prove it's a Lisp_Object. */ static INLINE void mark_maybe_object (obj) Lisp_Object obj; { void *po = (void *) XPNTR (obj); struct mem_node *m = mem_find (po); if (m != MEM_NIL) { int mark_p = 0; switch (XGCTYPE (obj)) { case Lisp_String: mark_p = (live_string_p (m, po) && !STRING_MARKED_P ((struct Lisp_String *) po)); break; case Lisp_Cons: mark_p = (live_cons_p (m, po) && !CONS_MARKED_P (XCONS (obj))); break; case Lisp_Symbol: mark_p = (live_symbol_p (m, po) && !XSYMBOL (obj)->gcmarkbit); break; case Lisp_Float: mark_p = (live_float_p (m, po) && !FLOAT_MARKED_P (XFLOAT (obj))); break; case Lisp_Vectorlike: /* Note: can't check GC_BUFFERP before we know it's a buffer because checking that dereferences the pointer PO which might point anywhere. */ if (live_vector_p (m, po)) mark_p = !GC_SUBRP (obj) && !VECTOR_MARKED_P (XVECTOR (obj)); else if (live_buffer_p (m, po)) mark_p = GC_BUFFERP (obj) && !VECTOR_MARKED_P (XBUFFER (obj)); break; case Lisp_Misc: mark_p = (live_misc_p (m, po) && !XMARKER (obj)->gcmarkbit); break; case Lisp_Int: case Lisp_Type_Limit: break; } if (mark_p) { #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES if (nzombies < MAX_ZOMBIES) zombies[nzombies] = obj; ++nzombies; #endif mark_object (obj); } } } /* If P points to Lisp data, mark that as live if it isn't already marked. */ static INLINE void mark_maybe_pointer (p) void *p; { struct mem_node *m; /* Quickly rule out some values which can't point to Lisp data. We assume that Lisp data is aligned on even addresses. */ if ((EMACS_INT) p & 1) return; m = mem_find (p); if (m != MEM_NIL) { Lisp_Object obj = Qnil; switch (m->type) { case MEM_TYPE_NON_LISP: /* Nothing to do; not a pointer to Lisp memory. */ break; case MEM_TYPE_BUFFER: if (live_buffer_p (m, p) && !VECTOR_MARKED_P((struct buffer *)p)) XSETVECTOR (obj, p); break; case MEM_TYPE_CONS: if (live_cons_p (m, p) && !CONS_MARKED_P ((struct Lisp_Cons *) p)) XSETCONS (obj, p); break; case MEM_TYPE_STRING: if (live_string_p (m, p) && !STRING_MARKED_P ((struct Lisp_String *) p)) XSETSTRING (obj, p); break; case MEM_TYPE_MISC: if (live_misc_p (m, p) && !((struct Lisp_Free *) p)->gcmarkbit) XSETMISC (obj, p); break; case MEM_TYPE_SYMBOL: if (live_symbol_p (m, p) && !((struct Lisp_Symbol *) p)->gcmarkbit) XSETSYMBOL (obj, p); break; case MEM_TYPE_FLOAT: if (live_float_p (m, p) && !FLOAT_MARKED_P (p)) XSETFLOAT (obj, p); break; case MEM_TYPE_VECTOR: case MEM_TYPE_PROCESS: case MEM_TYPE_HASH_TABLE: case MEM_TYPE_FRAME: case MEM_TYPE_WINDOW: if (live_vector_p (m, p)) { Lisp_Object tem; XSETVECTOR (tem, p); if (!GC_SUBRP (tem) && !VECTOR_MARKED_P (XVECTOR (tem))) obj = tem; } break; default: abort (); } if (!GC_NILP (obj)) mark_object (obj); } } /* Mark Lisp objects referenced from the address range START..END. */ static void mark_memory (start, end) void *start, *end; { Lisp_Object *p; void **pp; #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES nzombies = 0; #endif /* Make START the pointer to the start of the memory region, if it isn't already. */ if (end < start) { void *tem = start; start = end; end = tem; } /* Mark Lisp_Objects. */ for (p = (Lisp_Object *) start; (void *) p < end; ++p) mark_maybe_object (*p); /* Mark Lisp data pointed to. This is necessary because, in some situations, the C compiler optimizes Lisp objects away, so that only a pointer to them remains. Example: DEFUN ("testme", Ftestme, Stestme, 0, 0, 0, "") () { Lisp_Object obj = build_string ("test"); struct Lisp_String *s = XSTRING (obj); Fgarbage_collect (); fprintf (stderr, "test `%s'\n", s->data); return Qnil; } Here, `obj' isn't really used, and the compiler optimizes it away. The only reference to the life string is through the pointer `s'. */ for (pp = (void **) start; (void *) pp < end; ++pp) mark_maybe_pointer (*pp); } /* setjmp will work with GCC unless NON_SAVING_SETJMP is defined in the GCC system configuration. In gcc 3.2, the only systems for which this is so are i386-sco5 non-ELF, i386-sysv3 (maybe included by others?) and ns32k-pc532-min. */ #if !defined GC_SAVE_REGISTERS_ON_STACK && !defined GC_SETJMP_WORKS static int setjmp_tested_p, longjmps_done; #define SETJMP_WILL_LIKELY_WORK "\ \n\ Emacs garbage collector has been changed to use conservative stack\n\ marking. Emacs has determined that the method it uses to do the\n\ marking will likely work on your system, but this isn't sure.\n\ \n\ If you are a system-programmer, or can get the help of a local wizard\n\ who is, please take a look at the function mark_stack in alloc.c, and\n\ verify that the methods used are appropriate for your system.\n\ \n\ Please mail the result to .\n\ " #define SETJMP_WILL_NOT_WORK "\ \n\ Emacs garbage collector has been changed to use conservative stack\n\ marking. Emacs has determined that the default method it uses to do the\n\ marking will not work on your system. We will need a system-dependent\n\ solution for your system.\n\ \n\ Please take a look at the function mark_stack in alloc.c, and\n\ try to find a way to make it work on your system.\n\ \n\ Note that you may get false negatives, depending on the compiler.\n\ In particular, you need to use -O with GCC for this test.\n\ \n\ Please mail the result to .\n\ " /* Perform a quick check if it looks like setjmp saves registers in a jmp_buf. Print a message to stderr saying so. When this test succeeds, this is _not_ a proof that setjmp is sufficient for conservative stack marking. Only the sources or a disassembly can prove that. */ static void test_setjmp () { char buf[10]; register int x; jmp_buf jbuf; int result = 0; /* Arrange for X to be put in a register. */ sprintf (buf, "1"); x = strlen (buf); x = 2 * x - 1; setjmp (jbuf); if (longjmps_done == 1) { /* Came here after the longjmp at the end of the function. If x == 1, the longjmp has restored the register to its value before the setjmp, and we can hope that setjmp saves all such registers in the jmp_buf, although that isn't sure. For other values of X, either something really strange is taking place, or the setjmp just didn't save the register. */ if (x == 1) fprintf (stderr, SETJMP_WILL_LIKELY_WORK); else { fprintf (stderr, SETJMP_WILL_NOT_WORK); exit (1); } } ++longjmps_done; x = 2; if (longjmps_done == 1) longjmp (jbuf, 1); } #endif /* not GC_SAVE_REGISTERS_ON_STACK && not GC_SETJMP_WORKS */ #if GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS /* Abort if anything GCPRO'd doesn't survive the GC. */ static void check_gcpros () { struct gcpro *p; int i; for (p = gcprolist; p; p = p->next) for (i = 0; i < p->nvars; ++i) if (!survives_gc_p (p->var[i])) /* FIXME: It's not necessarily a bug. It might just be that the GCPRO is unnecessary or should release the object sooner. */ abort (); } #elif GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES static void dump_zombies () { int i; fprintf (stderr, "\nZombies kept alive = %d:\n", nzombies); for (i = 0; i < min (MAX_ZOMBIES, nzombies); ++i) { fprintf (stderr, " %d = ", i); debug_print (zombies[i]); } } #endif /* GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES */ /* Mark live Lisp objects on the C stack. There are several system-dependent problems to consider when porting this to new architectures: Processor Registers We have to mark Lisp objects in CPU registers that can hold local variables or are used to pass parameters. If GC_SAVE_REGISTERS_ON_STACK is defined, it should expand to something that either saves relevant registers on the stack, or calls mark_maybe_object passing it each register's contents. If GC_SAVE_REGISTERS_ON_STACK is not defined, the current implementation assumes that calling setjmp saves registers we need to see in a jmp_buf which itself lies on the stack. This doesn't have to be true! It must be verified for each system, possibly by taking a look at the source code of setjmp. Stack Layout Architectures differ in the way their processor stack is organized. For example, the stack might look like this +----------------+ | Lisp_Object | size = 4 +----------------+ | something else | size = 2 +----------------+ | Lisp_Object | size = 4 +----------------+ | ... | In such a case, not every Lisp_Object will be aligned equally. To find all Lisp_Object on the stack it won't be sufficient to walk the stack in steps of 4 bytes. Instead, two passes will be necessary, one starting at the start of the stack, and a second pass starting at the start of the stack + 2. Likewise, if the minimal alignment of Lisp_Objects on the stack is 1, four passes would be necessary, each one starting with one byte more offset from the stack start. The current code assumes by default that Lisp_Objects are aligned equally on the stack. */ static void mark_stack () { int i; jmp_buf j; volatile int stack_grows_down_p = (char *) &j > (char *) stack_base; void *end; /* This trick flushes the register windows so that all the state of the process is contained in the stack. */ /* Fixme: Code in the Boehm GC suggests flushing (with `flushrs') is needed on ia64 too. See mach_dep.c, where it also says inline assembler doesn't work with relevant proprietary compilers. */ #ifdef sparc asm ("ta 3"); #endif /* Save registers that we need to see on the stack. We need to see registers used to hold register variables and registers used to pass parameters. */ #ifdef GC_SAVE_REGISTERS_ON_STACK GC_SAVE_REGISTERS_ON_STACK (end); #else /* not GC_SAVE_REGISTERS_ON_STACK */ #ifndef GC_SETJMP_WORKS /* If it hasn't been checked yet that setjmp will definitely work, test it and print a message with the result of the test. */ if (!setjmp_tested_p) { setjmp_tested_p = 1; test_setjmp (); } #endif /* GC_SETJMP_WORKS */ setjmp (j); end = stack_grows_down_p ? (char *) &j + sizeof j : (char *) &j; #endif /* not GC_SAVE_REGISTERS_ON_STACK */ /* This assumes that the stack is a contiguous region in memory. If that's not the case, something has to be done here to iterate over the stack segments. */ #ifndef GC_LISP_OBJECT_ALIGNMENT #ifdef __GNUC__ #define GC_LISP_OBJECT_ALIGNMENT __alignof__ (Lisp_Object) #else #define GC_LISP_OBJECT_ALIGNMENT sizeof (Lisp_Object) #endif #endif for (i = 0; i < sizeof (Lisp_Object); i += GC_LISP_OBJECT_ALIGNMENT) mark_memory ((char *) stack_base + i, end); /* Allow for marking a secondary stack, like the register stack on the ia64. */ #ifdef GC_MARK_SECONDARY_STACK GC_MARK_SECONDARY_STACK (); #endif #if GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS check_gcpros (); #endif } #endif /* GC_MARK_STACK != 0 */ /* Determine whether it is safe to access memory at address P. */ int valid_pointer_p (p) void *p; { #ifdef WINDOWSNT return w32_valid_pointer_p (p, 16); #else int fd; /* Obviously, we cannot just access it (we would SEGV trying), so we trick the o/s to tell us whether p is a valid pointer. Unfortunately, we cannot use NULL_DEVICE here, as emacs_write may not validate p in that case. */ if ((fd = emacs_open ("__Valid__Lisp__Object__", O_CREAT | O_WRONLY | O_TRUNC, 0666)) >= 0) { int valid = (emacs_write (fd, (char *)p, 16) == 16); emacs_close (fd); unlink ("__Valid__Lisp__Object__"); return valid; } return -1; #endif } /* Return 1 if OBJ is a valid lisp object. Return 0 if OBJ is NOT a valid lisp object. Return -1 if we cannot validate OBJ. This function can be quite slow, so it should only be used in code for manual debugging. */ int valid_lisp_object_p (obj) Lisp_Object obj; { void *p; #if GC_MARK_STACK struct mem_node *m; #endif if (INTEGERP (obj)) return 1; p = (void *) XPNTR (obj); if (PURE_POINTER_P (p)) return 1; #if !GC_MARK_STACK return valid_pointer_p (p); #else m = mem_find (p); if (m == MEM_NIL) { int valid = valid_pointer_p (p); if (valid <= 0) return valid; if (SUBRP (obj)) return 1; return 0; } switch (m->type) { case MEM_TYPE_NON_LISP: return 0; case MEM_TYPE_BUFFER: return live_buffer_p (m, p); case MEM_TYPE_CONS: return live_cons_p (m, p); case MEM_TYPE_STRING: return live_string_p (m, p); case MEM_TYPE_MISC: return live_misc_p (m, p); case MEM_TYPE_SYMBOL: return live_symbol_p (m, p); case MEM_TYPE_FLOAT: return live_float_p (m, p); case MEM_TYPE_VECTOR: case MEM_TYPE_PROCESS: case MEM_TYPE_HASH_TABLE: case MEM_TYPE_FRAME: case MEM_TYPE_WINDOW: return live_vector_p (m, p); default: break; } return 0; #endif } /*********************************************************************** Pure Storage Management ***********************************************************************/ /* Allocate room for SIZE bytes from pure Lisp storage and return a pointer to it. TYPE is the Lisp type for which the memory is allocated. TYPE < 0 means it's not used for a Lisp object. */ static POINTER_TYPE * pure_alloc (size, type) size_t size; int type; { POINTER_TYPE *result; #ifdef USE_LSB_TAG size_t alignment = (1 << GCTYPEBITS); #else size_t alignment = sizeof (EMACS_INT); /* Give Lisp_Floats an extra alignment. */ if (type == Lisp_Float) { #if defined __GNUC__ && __GNUC__ >= 2 alignment = __alignof (struct Lisp_Float); #else alignment = sizeof (struct Lisp_Float); #endif } #endif again: if (type >= 0) { /* Allocate space for a Lisp object from the beginning of the free space with taking account of alignment. */ result = ALIGN (purebeg + pure_bytes_used_lisp, alignment); pure_bytes_used_lisp = ((char *)result - (char *)purebeg) + size; } else { /* Allocate space for a non-Lisp object from the end of the free space. */ pure_bytes_used_non_lisp += size; result = purebeg + pure_size - pure_bytes_used_non_lisp; } pure_bytes_used = pure_bytes_used_lisp + pure_bytes_used_non_lisp; if (pure_bytes_used <= pure_size) return result; /* Don't allocate a large amount here, because it might get mmap'd and then its address might not be usable. */ purebeg = (char *) xmalloc (10000); pure_size = 10000; pure_bytes_used_before_overflow += pure_bytes_used - size; pure_bytes_used = 0; pure_bytes_used_lisp = pure_bytes_used_non_lisp = 0; goto again; } /* Print a warning if PURESIZE is too small. */ void check_pure_size () { if (pure_bytes_used_before_overflow) message ("emacs:0:Pure Lisp storage overflow (approx. %d bytes needed)", (int) (pure_bytes_used + pure_bytes_used_before_overflow)); } /* Find the byte sequence {DATA[0], ..., DATA[NBYTES-1], '\0'} from the non-Lisp data pool of the pure storage, and return its start address. Return NULL if not found. */ static char * find_string_data_in_pure (data, nbytes) char *data; int nbytes; { int i, skip, bm_skip[256], last_char_skip, infinity, start, start_max; unsigned char *p; char *non_lisp_beg; if (pure_bytes_used_non_lisp < nbytes + 1) return NULL; /* Set up the Boyer-Moore table. */ skip = nbytes + 1; for (i = 0; i < 256; i++) bm_skip[i] = skip; p = (unsigned char *) data; while (--skip > 0) bm_skip[*p++] = skip; last_char_skip = bm_skip['\0']; non_lisp_beg = purebeg + pure_size - pure_bytes_used_non_lisp; start_max = pure_bytes_used_non_lisp - (nbytes + 1); /* See the comments in the function `boyer_moore' (search.c) for the use of `infinity'. */ infinity = pure_bytes_used_non_lisp + 1; bm_skip['\0'] = infinity; p = (unsigned char *) non_lisp_beg + nbytes; start = 0; do { /* Check the last character (== '\0'). */ do { start += bm_skip[*(p + start)]; } while (start <= start_max); if (start < infinity) /* Couldn't find the last character. */ return NULL; /* No less than `infinity' means we could find the last character at `p[start - infinity]'. */ start -= infinity; /* Check the remaining characters. */ if (memcmp (data, non_lisp_beg + start, nbytes) == 0) /* Found. */ return non_lisp_beg + start; start += last_char_skip; } while (start <= start_max); return NULL; } /* Return a string allocated in pure space. DATA is a buffer holding NCHARS characters, and NBYTES bytes of string data. MULTIBYTE non-zero means make the result string multibyte. Must get an error if pure storage is full, since if it cannot hold a large string it may be able to hold conses that point to that string; then the string is not protected from gc. */ Lisp_Object make_pure_string (data, nchars, nbytes, multibyte) char *data; int nchars, nbytes; int multibyte; { Lisp_Object string; struct Lisp_String *s; s = (struct Lisp_String *) pure_alloc (sizeof *s, Lisp_String); s->data = find_string_data_in_pure (data, nbytes); if (s->data == NULL) { s->data = (unsigned char *) pure_alloc (nbytes + 1, -1); bcopy (data, s->data, nbytes); s->data[nbytes] = '\0'; } s->size = nchars; s->size_byte = multibyte ? nbytes : -1; s->intervals = NULL_INTERVAL; XSETSTRING (string, s); return string; } /* Return a cons allocated from pure space. Give it pure copies of CAR as car and CDR as cdr. */ Lisp_Object pure_cons (car, cdr) Lisp_Object car, cdr; { register Lisp_Object new; struct Lisp_Cons *p; p = (struct Lisp_Cons *) pure_alloc (sizeof *p, Lisp_Cons); XSETCONS (new, p); XSETCAR (new, Fpurecopy (car)); XSETCDR (new, Fpurecopy (cdr)); return new; } /* Value is a float object with value NUM allocated from pure space. */ Lisp_Object make_pure_float (num) double num; { register Lisp_Object new; struct Lisp_Float *p; p = (struct Lisp_Float *) pure_alloc (sizeof *p, Lisp_Float); XSETFLOAT (new, p); XFLOAT_DATA (new) = num; return new; } /* Return a vector with room for LEN Lisp_Objects allocated from pure space. */ Lisp_Object make_pure_vector (len) EMACS_INT len; { Lisp_Object new; struct Lisp_Vector *p; size_t size = sizeof *p + (len - 1) * sizeof (Lisp_Object); p = (struct Lisp_Vector *) pure_alloc (size, Lisp_Vectorlike); XSETVECTOR (new, p); XVECTOR (new)->size = len; return new; } DEFUN ("purecopy", Fpurecopy, Spurecopy, 1, 1, 0, doc: /* Make a copy of object OBJ in pure storage. Recursively copies contents of vectors and cons cells. Does not copy symbols. Copies strings without text properties. */) (obj) register Lisp_Object obj; { if (NILP (Vpurify_flag)) return obj; if (PURE_POINTER_P (XPNTR (obj))) return obj; if (CONSP (obj)) return pure_cons (XCAR (obj), XCDR (obj)); else if (FLOATP (obj)) return make_pure_float (XFLOAT_DATA (obj)); else if (STRINGP (obj)) return make_pure_string (SDATA (obj), SCHARS (obj), SBYTES (obj), STRING_MULTIBYTE (obj)); else if (COMPILEDP (obj) || VECTORP (obj)) { register struct Lisp_Vector *vec; register int i; EMACS_INT size; size = XVECTOR (obj)->size; if (size & PSEUDOVECTOR_FLAG) size &= PSEUDOVECTOR_SIZE_MASK; vec = XVECTOR (make_pure_vector (size)); for (i = 0; i < size; i++) vec->contents[i] = Fpurecopy (XVECTOR (obj)->contents[i]); if (COMPILEDP (obj)) XSETCOMPILED (obj, vec); else XSETVECTOR (obj, vec); return obj; } else if (MARKERP (obj)) error ("Attempt to copy a marker to pure storage"); return obj; } /*********************************************************************** Protection from GC ***********************************************************************/ /* Put an entry in staticvec, pointing at the variable with address VARADDRESS. */ void staticpro (varaddress) Lisp_Object *varaddress; { staticvec[staticidx++] = varaddress; if (staticidx >= NSTATICS) abort (); } struct catchtag { Lisp_Object tag; Lisp_Object val; struct catchtag *next; }; /*********************************************************************** Protection from GC ***********************************************************************/ /* Temporarily prevent garbage collection. */ int inhibit_garbage_collection () { int count = SPECPDL_INDEX (); int nbits = min (VALBITS, BITS_PER_INT); specbind (Qgc_cons_threshold, make_number (((EMACS_INT) 1 << (nbits - 1)) - 1)); return count; } DEFUN ("garbage-collect", Fgarbage_collect, Sgarbage_collect, 0, 0, "", doc: /* Reclaim storage for Lisp objects no longer needed. Garbage collection happens automatically if you cons more than `gc-cons-threshold' bytes of Lisp data since previous garbage collection. `garbage-collect' normally returns a list with info on amount of space in use: ((USED-CONSES . FREE-CONSES) (USED-SYMS . FREE-SYMS) (USED-MARKERS . FREE-MARKERS) USED-STRING-CHARS USED-VECTOR-SLOTS (USED-FLOATS . FREE-FLOATS) (USED-INTERVALS . FREE-INTERVALS) (USED-STRINGS . FREE-STRINGS)) However, if there was overflow in pure space, `garbage-collect' returns nil, because real GC can't be done. */) () { register struct specbinding *bind; struct catchtag *catch; struct handler *handler; char stack_top_variable; register int i; int message_p; Lisp_Object total[8]; int count = SPECPDL_INDEX (); EMACS_TIME t1, t2, t3; if (abort_on_gc) abort (); /* Can't GC if pure storage overflowed because we can't determine if something is a pure object or not. */ if (pure_bytes_used_before_overflow) return Qnil; CHECK_CONS_LIST (); /* Don't keep undo information around forever. Do this early on, so it is no problem if the user quits. */ { register struct buffer *nextb = all_buffers; while (nextb) { /* If a buffer's undo list is Qt, that means that undo is turned off in that buffer. Calling truncate_undo_list on Qt tends to return NULL, which effectively turns undo back on. So don't call truncate_undo_list if undo_list is Qt. */ if (! NILP (nextb->name) && ! EQ (nextb->undo_list, Qt)) truncate_undo_list (nextb); /* Shrink buffer gaps, but skip indirect and dead buffers. */ if (nextb->base_buffer == 0 && !NILP (nextb->name)) { /* If a buffer's gap size is more than 10% of the buffer size, or larger than 2000 bytes, then shrink it accordingly. Keep a minimum size of 20 bytes. */ int size = min (2000, max (20, (nextb->text->z_byte / 10))); if (nextb->text->gap_size > size) { struct buffer *save_current = current_buffer; current_buffer = nextb; make_gap (-(nextb->text->gap_size - size)); current_buffer = save_current; } } nextb = nextb->next; } } EMACS_GET_TIME (t1); /* In case user calls debug_print during GC, don't let that cause a recursive GC. */ consing_since_gc = 0; /* Save what's currently displayed in the echo area. */ message_p = push_message (); record_unwind_protect (pop_message_unwind, Qnil); /* Save a copy of the contents of the stack, for debugging. */ #if MAX_SAVE_STACK > 0 if (NILP (Vpurify_flag)) { i = &stack_top_variable - stack_bottom; if (i < 0) i = -i; if (i < MAX_SAVE_STACK) { if (stack_copy == 0) stack_copy = (char *) xmalloc (stack_copy_size = i); else if (stack_copy_size < i) stack_copy = (char *) xrealloc (stack_copy, (stack_copy_size = i)); if (stack_copy) { if ((EMACS_INT) (&stack_top_variable - stack_bottom) > 0) bcopy (stack_bottom, stack_copy, i); else bcopy (&stack_top_variable, stack_copy, i); } } } #endif /* MAX_SAVE_STACK > 0 */ if (garbage_collection_messages) message1_nolog ("Garbage collecting..."); BLOCK_INPUT; shrink_regexp_cache (); gc_in_progress = 1; /* clear_marks (); */ /* Mark all the special slots that serve as the roots of accessibility. */ for (i = 0; i < staticidx; i++) mark_object (*staticvec[i]); for (bind = specpdl; bind != specpdl_ptr; bind++) { mark_object (bind->symbol); mark_object (bind->old_value); } mark_kboards (); #ifdef USE_GTK { extern void xg_mark_data (); xg_mark_data (); } #endif #if (GC_MARK_STACK == GC_MAKE_GCPROS_NOOPS \ || GC_MARK_STACK == GC_MARK_STACK_CHECK_GCPROS) mark_stack (); #else { register struct gcpro *tail; for (tail = gcprolist; tail; tail = tail->next) for (i = 0; i < tail->nvars; i++) mark_object (tail->var[i]); } #endif mark_byte_stack (); for (catch = catchlist; catch; catch = catch->next) { mark_object (catch->tag); mark_object (catch->val); } for (handler = handlerlist; handler; handler = handler->next) { mark_object (handler->handler); mark_object (handler->var); } mark_backtrace (); #ifdef HAVE_WINDOW_SYSTEM mark_fringe_data (); #endif #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES mark_stack (); #endif /* Everything is now marked, except for the things that require special finalization, i.e. the undo_list. Look thru every buffer's undo list for elements that update markers that were not marked, and delete them. */ { register struct buffer *nextb = all_buffers; while (nextb) { /* If a buffer's undo list is Qt, that means that undo is turned off in that buffer. Calling truncate_undo_list on Qt tends to return NULL, which effectively turns undo back on. So don't call truncate_undo_list if undo_list is Qt. */ if (! EQ (nextb->undo_list, Qt)) { Lisp_Object tail, prev; tail = nextb->undo_list; prev = Qnil; while (CONSP (tail)) { if (GC_CONSP (XCAR (tail)) && GC_MARKERP (XCAR (XCAR (tail))) && !XMARKER (XCAR (XCAR (tail)))->gcmarkbit) { if (NILP (prev)) nextb->undo_list = tail = XCDR (tail); else { tail = XCDR (tail); XSETCDR (prev, tail); } } else { prev = tail; tail = XCDR (tail); } } } /* Now that we have stripped the elements that need not be in the undo_list any more, we can finally mark the list. */ mark_object (nextb->undo_list); nextb = nextb->next; } } gc_sweep (); /* Clear the mark bits that we set in certain root slots. */ unmark_byte_stack (); VECTOR_UNMARK (&buffer_defaults); VECTOR_UNMARK (&buffer_local_symbols); #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES && 0 dump_zombies (); #endif UNBLOCK_INPUT; CHECK_CONS_LIST (); /* clear_marks (); */ gc_in_progress = 0; consing_since_gc = 0; if (gc_cons_threshold < 10000) gc_cons_threshold = 10000; if (FLOATP (Vgc_cons_percentage)) { /* Set gc_cons_combined_threshold. */ EMACS_INT total = 0; total += total_conses * sizeof (struct Lisp_Cons); total += total_symbols * sizeof (struct Lisp_Symbol); total += total_markers * sizeof (union Lisp_Misc); total += total_string_size; total += total_vector_size * sizeof (Lisp_Object); total += total_floats * sizeof (struct Lisp_Float); total += total_intervals * sizeof (struct interval); total += total_strings * sizeof (struct Lisp_String); gc_relative_threshold = total * XFLOAT_DATA (Vgc_cons_percentage); } else gc_relative_threshold = 0; if (garbage_collection_messages) { if (message_p || minibuf_level > 0) restore_message (); else message1_nolog ("Garbage collecting...done"); } unbind_to (count, Qnil); total[0] = Fcons (make_number (total_conses), make_number (total_free_conses)); total[1] = Fcons (make_number (total_symbols), make_number (total_free_symbols)); total[2] = Fcons (make_number (total_markers), make_number (total_free_markers)); total[3] = make_number (total_string_size); total[4] = make_number (total_vector_size); total[5] = Fcons (make_number (total_floats), make_number (total_free_floats)); total[6] = Fcons (make_number (total_intervals), make_number (total_free_intervals)); total[7] = Fcons (make_number (total_strings), make_number (total_free_strings)); #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES { /* Compute average percentage of zombies. */ double nlive = 0; for (i = 0; i < 7; ++i) if (CONSP (total[i])) nlive += XFASTINT (XCAR (total[i])); avg_live = (avg_live * ngcs + nlive) / (ngcs + 1); max_live = max (nlive, max_live); avg_zombies = (avg_zombies * ngcs + nzombies) / (ngcs + 1); max_zombies = max (nzombies, max_zombies); ++ngcs; } #endif if (!NILP (Vpost_gc_hook)) { int count = inhibit_garbage_collection (); safe_run_hooks (Qpost_gc_hook); unbind_to (count, Qnil); } /* Accumulate statistics. */ EMACS_GET_TIME (t2); EMACS_SUB_TIME (t3, t2, t1); if (FLOATP (Vgc_elapsed)) Vgc_elapsed = make_float (XFLOAT_DATA (Vgc_elapsed) + EMACS_SECS (t3) + EMACS_USECS (t3) * 1.0e-6); gcs_done++; return Flist (sizeof total / sizeof *total, total); } /* Mark Lisp objects in glyph matrix MATRIX. Currently the only interesting objects referenced from glyphs are strings. */ static void mark_glyph_matrix (matrix) struct glyph_matrix *matrix; { struct glyph_row *row = matrix->rows; struct glyph_row *end = row + matrix->nrows; for (; row < end; ++row) if (row->enabled_p) { int area; for (area = LEFT_MARGIN_AREA; area < LAST_AREA; ++area) { struct glyph *glyph = row->glyphs[area]; struct glyph *end_glyph = glyph + row->used[area]; for (; glyph < end_glyph; ++glyph) if (GC_STRINGP (glyph->object) && !STRING_MARKED_P (XSTRING (glyph->object))) mark_object (glyph->object); } } } /* Mark Lisp faces in the face cache C. */ static void mark_face_cache (c) struct face_cache *c; { if (c) { int i, j; for (i = 0; i < c->used; ++i) { struct face *face = FACE_FROM_ID (c->f, i); if (face) { for (j = 0; j < LFACE_VECTOR_SIZE; ++j) mark_object (face->lface[j]); } } } } #ifdef HAVE_WINDOW_SYSTEM /* Mark Lisp objects in image IMG. */ static void mark_image (img) struct image *img; { mark_object (img->spec); if (!NILP (img->data.lisp_val)) mark_object (img->data.lisp_val); } /* Mark Lisp objects in image cache of frame F. It's done this way so that we don't have to include xterm.h here. */ static void mark_image_cache (f) struct frame *f; { forall_images_in_image_cache (f, mark_image); } #endif /* HAVE_X_WINDOWS */ /* Mark reference to a Lisp_Object. If the object referred to has not been seen yet, recursively mark all the references contained in it. */ #define LAST_MARKED_SIZE 500 Lisp_Object last_marked[LAST_MARKED_SIZE]; int last_marked_index; /* For debugging--call abort when we cdr down this many links of a list, in mark_object. In debugging, the call to abort will hit a breakpoint. Normally this is zero and the check never goes off. */ int mark_object_loop_halt; void mark_object (arg) Lisp_Object arg; { register Lisp_Object obj = arg; #ifdef GC_CHECK_MARKED_OBJECTS void *po; struct mem_node *m; #endif int cdr_count = 0; loop: if (PURE_POINTER_P (XPNTR (obj))) return; last_marked[last_marked_index++] = obj; if (last_marked_index == LAST_MARKED_SIZE) last_marked_index = 0; /* Perform some sanity checks on the objects marked here. Abort if we encounter an object we know is bogus. This increases GC time by ~80%, and requires compilation with GC_MARK_STACK != 0. */ #ifdef GC_CHECK_MARKED_OBJECTS po = (void *) XPNTR (obj); /* Check that the object pointed to by PO is known to be a Lisp structure allocated from the heap. */ #define CHECK_ALLOCATED() \ do { \ m = mem_find (po); \ if (m == MEM_NIL) \ abort (); \ } while (0) /* Check that the object pointed to by PO is live, using predicate function LIVEP. */ #define CHECK_LIVE(LIVEP) \ do { \ if (!LIVEP (m, po)) \ abort (); \ } while (0) /* Check both of the above conditions. */ #define CHECK_ALLOCATED_AND_LIVE(LIVEP) \ do { \ CHECK_ALLOCATED (); \ CHECK_LIVE (LIVEP); \ } while (0) \ #else /* not GC_CHECK_MARKED_OBJECTS */ #define CHECK_ALLOCATED() (void) 0 #define CHECK_LIVE(LIVEP) (void) 0 #define CHECK_ALLOCATED_AND_LIVE(LIVEP) (void) 0 #endif /* not GC_CHECK_MARKED_OBJECTS */ switch (SWITCH_ENUM_CAST (XGCTYPE (obj))) { case Lisp_String: { register struct Lisp_String *ptr = XSTRING (obj); CHECK_ALLOCATED_AND_LIVE (live_string_p); MARK_INTERVAL_TREE (ptr->intervals); MARK_STRING (ptr); #ifdef GC_CHECK_STRING_BYTES /* Check that the string size recorded in the string is the same as the one recorded in the sdata structure. */ CHECK_STRING_BYTES (ptr); #endif /* GC_CHECK_STRING_BYTES */ } break; case Lisp_Vectorlike: #ifdef GC_CHECK_MARKED_OBJECTS m = mem_find (po); if (m == MEM_NIL && !GC_SUBRP (obj) && po != &buffer_defaults && po != &buffer_local_symbols) abort (); #endif /* GC_CHECK_MARKED_OBJECTS */ if (GC_BUFFERP (obj)) { if (!VECTOR_MARKED_P (XBUFFER (obj))) { #ifdef GC_CHECK_MARKED_OBJECTS if (po != &buffer_defaults && po != &buffer_local_symbols) { struct buffer *b; for (b = all_buffers; b && b != po; b = b->next) ; if (b == NULL) abort (); } #endif /* GC_CHECK_MARKED_OBJECTS */ mark_buffer (obj); } } else if (GC_SUBRP (obj)) break; else if (GC_COMPILEDP (obj)) /* We could treat this just like a vector, but it is better to save the COMPILED_CONSTANTS element for last and avoid recursion there. */ { register struct Lisp_Vector *ptr = XVECTOR (obj); register EMACS_INT size = ptr->size; register int i; if (VECTOR_MARKED_P (ptr)) break; /* Already marked */ CHECK_LIVE (live_vector_p); VECTOR_MARK (ptr); /* Else mark it */ size &= PSEUDOVECTOR_SIZE_MASK; for (i = 0; i < size; i++) /* and then mark its elements */ { if (i != COMPILED_CONSTANTS) mark_object (ptr->contents[i]); } obj = ptr->contents[COMPILED_CONSTANTS]; goto loop; } else if (GC_FRAMEP (obj)) { register struct frame *ptr = XFRAME (obj); if (VECTOR_MARKED_P (ptr)) break; /* Already marked */ VECTOR_MARK (ptr); /* Else mark it */ CHECK_LIVE (live_vector_p); mark_object (ptr->name); mark_object (ptr->icon_name); mark_object (ptr->title); mark_object (ptr->focus_frame); mark_object (ptr->selected_window); mark_object (ptr->minibuffer_window); mark_object (ptr->param_alist); mark_object (ptr->scroll_bars); mark_object (ptr->condemned_scroll_bars); mark_object (ptr->menu_bar_items); mark_object (ptr->face_alist); mark_object (ptr->menu_bar_vector); mark_object (ptr->buffer_predicate); mark_object (ptr->buffer_list); mark_object (ptr->menu_bar_window); mark_object (ptr->tool_bar_window); mark_face_cache (ptr->face_cache); #ifdef HAVE_WINDOW_SYSTEM mark_image_cache (ptr); mark_object (ptr->tool_bar_items); mark_object (ptr->desired_tool_bar_string); mark_object (ptr->current_tool_bar_string); #endif /* HAVE_WINDOW_SYSTEM */ } else if (GC_BOOL_VECTOR_P (obj)) { register struct Lisp_Vector *ptr = XVECTOR (obj); if (VECTOR_MARKED_P (ptr)) break; /* Already marked */ CHECK_LIVE (live_vector_p); VECTOR_MARK (ptr); /* Else mark it */ } else if (GC_WINDOWP (obj)) { register struct Lisp_Vector *ptr = XVECTOR (obj); struct window *w = XWINDOW (obj); register int i; /* Stop if already marked. */ if (VECTOR_MARKED_P (ptr)) break; /* Mark it. */ CHECK_LIVE (live_vector_p); VECTOR_MARK (ptr); /* There is no Lisp data above The member CURRENT_MATRIX in struct WINDOW. Stop marking when that slot is reached. */ for (i = 0; (char *) &ptr->contents[i] < (char *) &w->current_matrix; i++) mark_object (ptr->contents[i]); /* Mark glyphs for leaf windows. Marking window matrices is sufficient because frame matrices use the same glyph memory. */ if (NILP (w->hchild) && NILP (w->vchild) && w->current_matrix) { mark_glyph_matrix (w->current_matrix); mark_glyph_matrix (w->desired_matrix); } } else if (GC_HASH_TABLE_P (obj)) { struct Lisp_Hash_Table *h = XHASH_TABLE (obj); /* Stop if already marked. */ if (VECTOR_MARKED_P (h)) break; /* Mark it. */ CHECK_LIVE (live_vector_p); VECTOR_MARK (h); /* Mark contents. */ /* Do not mark next_free or next_weak. Being in the next_weak chain should not keep the hash table alive. No need to mark `count' since it is an integer. */ mark_object (h->test); mark_object (h->weak); mark_object (h->rehash_size); mark_object (h->rehash_threshold); mark_object (h->hash); mark_object (h->next); mark_object (h->index); mark_object (h->user_hash_function); mark_object (h->user_cmp_function); /* If hash table is not weak, mark all keys and values. For weak tables, mark only the vector. */ if (GC_NILP (h->weak)) mark_object (h->key_and_value); else VECTOR_MARK (XVECTOR (h->key_and_value)); } else { register struct Lisp_Vector *ptr = XVECTOR (obj); register EMACS_INT size = ptr->size; register int i; if (VECTOR_MARKED_P (ptr)) break; /* Already marked */ CHECK_LIVE (live_vector_p); VECTOR_MARK (ptr); /* Else mark it */ if (size & PSEUDOVECTOR_FLAG) size &= PSEUDOVECTOR_SIZE_MASK; /* Note that this size is not the memory-footprint size, but only the number of Lisp_Object fields that we should trace. The distinction is used e.g. by Lisp_Process which places extra non-Lisp_Object fields at the end of the structure. */ for (i = 0; i < size; i++) /* and then mark its elements */ mark_object (ptr->contents[i]); } break; case Lisp_Symbol: { register struct Lisp_Symbol *ptr = XSYMBOL (obj); struct Lisp_Symbol *ptrx; if (ptr->gcmarkbit) break; CHECK_ALLOCATED_AND_LIVE (live_symbol_p); ptr->gcmarkbit = 1; mark_object (ptr->value); mark_object (ptr->function); mark_object (ptr->plist); if (!PURE_POINTER_P (XSTRING (ptr->xname))) MARK_STRING (XSTRING (ptr->xname)); MARK_INTERVAL_TREE (STRING_INTERVALS (ptr->xname)); /* Note that we do not mark the obarray of the symbol. It is safe not to do so because nothing accesses that slot except to check whether it is nil. */ ptr = ptr->next; if (ptr) { ptrx = ptr; /* Use of ptrx avoids compiler bug on Sun */ XSETSYMBOL (obj, ptrx); goto loop; } } break; case Lisp_Misc: CHECK_ALLOCATED_AND_LIVE (live_misc_p); if (XMARKER (obj)->gcmarkbit) break; XMARKER (obj)->gcmarkbit = 1; switch (XMISCTYPE (obj)) { case Lisp_Misc_Buffer_Local_Value: case Lisp_Misc_Some_Buffer_Local_Value: { register struct Lisp_Buffer_Local_Value *ptr = XBUFFER_LOCAL_VALUE (obj); /* If the cdr is nil, avoid recursion for the car. */ if (EQ (ptr->cdr, Qnil)) { obj = ptr->realvalue; goto loop; } mark_object (ptr->realvalue); mark_object (ptr->buffer); mark_object (ptr->frame); obj = ptr->cdr; goto loop; } case Lisp_Misc_Marker: /* DO NOT mark thru the marker's chain. The buffer's markers chain does not preserve markers from gc; instead, markers are removed from the chain when freed by gc. */ break; case Lisp_Misc_Intfwd: case Lisp_Misc_Boolfwd: case Lisp_Misc_Objfwd: case Lisp_Misc_Buffer_Objfwd: case Lisp_Misc_Kboard_Objfwd: /* Don't bother with Lisp_Buffer_Objfwd, since all markable slots in current buffer marked anyway. */ /* Don't need to do Lisp_Objfwd, since the places they point are protected with staticpro. */ break; case Lisp_Misc_Save_Value: #if GC_MARK_STACK { register struct Lisp_Save_Value *ptr = XSAVE_VALUE (obj); /* If DOGC is set, POINTER is the address of a memory area containing INTEGER potential Lisp_Objects. */ if (ptr->dogc) { Lisp_Object *p = (Lisp_Object *) ptr->pointer; int nelt; for (nelt = ptr->integer; nelt > 0; nelt--, p++) mark_maybe_object (*p); } } #endif break; case Lisp_Misc_Overlay: { struct Lisp_Overlay *ptr = XOVERLAY (obj); mark_object (ptr->start); mark_object (ptr->end); mark_object (ptr->plist); if (ptr->next) { XSETMISC (obj, ptr->next); goto loop; } } break; default: abort (); } break; case Lisp_Cons: { register struct Lisp_Cons *ptr = XCONS (obj); if (CONS_MARKED_P (ptr)) break; CHECK_ALLOCATED_AND_LIVE (live_cons_p); CONS_MARK (ptr); /* If the cdr is nil, avoid recursion for the car. */ if (EQ (ptr->u.cdr, Qnil)) { obj = ptr->car; cdr_count = 0; goto loop; } mark_object (ptr->car); obj = ptr->u.cdr; cdr_count++; if (cdr_count == mark_object_loop_halt) abort (); goto loop; } case Lisp_Float: CHECK_ALLOCATED_AND_LIVE (live_float_p); FLOAT_MARK (XFLOAT (obj)); break; case Lisp_Int: break; default: abort (); } #undef CHECK_LIVE #undef CHECK_ALLOCATED #undef CHECK_ALLOCATED_AND_LIVE } /* Mark the pointers in a buffer structure. */ static void mark_buffer (buf) Lisp_Object buf; { register struct buffer *buffer = XBUFFER (buf); register Lisp_Object *ptr, tmp; Lisp_Object base_buffer; VECTOR_MARK (buffer); MARK_INTERVAL_TREE (BUF_INTERVALS (buffer)); /* For now, we just don't mark the undo_list. It's done later in a special way just before the sweep phase, and after stripping some of its elements that are not needed any more. */ if (buffer->overlays_before) { XSETMISC (tmp, buffer->overlays_before); mark_object (tmp); } if (buffer->overlays_after) { XSETMISC (tmp, buffer->overlays_after); mark_object (tmp); } for (ptr = &buffer->name; (char *)ptr < (char *)buffer + sizeof (struct buffer); ptr++) mark_object (*ptr); /* If this is an indirect buffer, mark its base buffer. */ if (buffer->base_buffer && !VECTOR_MARKED_P (buffer->base_buffer)) { XSETBUFFER (base_buffer, buffer->base_buffer); mark_buffer (base_buffer); } } /* Value is non-zero if OBJ will survive the current GC because it's either marked or does not need to be marked to survive. */ int survives_gc_p (obj) Lisp_Object obj; { int survives_p; switch (XGCTYPE (obj)) { case Lisp_Int: survives_p = 1; break; case Lisp_Symbol: survives_p = XSYMBOL (obj)->gcmarkbit; break; case Lisp_Misc: survives_p = XMARKER (obj)->gcmarkbit; break; case Lisp_String: survives_p = STRING_MARKED_P (XSTRING (obj)); break; case Lisp_Vectorlike: survives_p = GC_SUBRP (obj) || VECTOR_MARKED_P (XVECTOR (obj)); break; case Lisp_Cons: survives_p = CONS_MARKED_P (XCONS (obj)); break; case Lisp_Float: survives_p = FLOAT_MARKED_P (XFLOAT (obj)); break; default: abort (); } return survives_p || PURE_POINTER_P ((void *) XPNTR (obj)); } /* Sweep: find all structures not marked, and free them. */ static void gc_sweep () { /* Remove or mark entries in weak hash tables. This must be done before any object is unmarked. */ sweep_weak_hash_tables (); sweep_strings (); #ifdef GC_CHECK_STRING_BYTES if (!noninteractive) check_string_bytes (1); #endif /* Put all unmarked conses on free list */ { register struct cons_block *cblk; struct cons_block **cprev = &cons_block; register int lim = cons_block_index; register int num_free = 0, num_used = 0; cons_free_list = 0; for (cblk = cons_block; cblk; cblk = *cprev) { register int i; int this_free = 0; for (i = 0; i < lim; i++) if (!CONS_MARKED_P (&cblk->conses[i])) { this_free++; cblk->conses[i].u.chain = cons_free_list; cons_free_list = &cblk->conses[i]; #if GC_MARK_STACK cons_free_list->car = Vdead; #endif } else { num_used++; CONS_UNMARK (&cblk->conses[i]); } lim = CONS_BLOCK_SIZE; /* If this block contains only free conses and we have already seen more than two blocks worth of free conses then deallocate this block. */ if (this_free == CONS_BLOCK_SIZE && num_free > CONS_BLOCK_SIZE) { *cprev = cblk->next; /* Unhook from the free list. */ cons_free_list = cblk->conses[0].u.chain; lisp_align_free (cblk); n_cons_blocks--; } else { num_free += this_free; cprev = &cblk->next; } } total_conses = num_used; total_free_conses = num_free; } /* Put all unmarked floats on free list */ { register struct float_block *fblk; struct float_block **fprev = &float_block; register int lim = float_block_index; register int num_free = 0, num_used = 0; float_free_list = 0; for (fblk = float_block; fblk; fblk = *fprev) { register int i; int this_free = 0; for (i = 0; i < lim; i++) if (!FLOAT_MARKED_P (&fblk->floats[i])) { this_free++; fblk->floats[i].u.chain = float_free_list; float_free_list = &fblk->floats[i]; } else { num_used++; FLOAT_UNMARK (&fblk->floats[i]); } lim = FLOAT_BLOCK_SIZE; /* If this block contains only free floats and we have already seen more than two blocks worth of free floats then deallocate this block. */ if (this_free == FLOAT_BLOCK_SIZE && num_free > FLOAT_BLOCK_SIZE) { *fprev = fblk->next; /* Unhook from the free list. */ float_free_list = fblk->floats[0].u.chain; lisp_align_free (fblk); n_float_blocks--; } else { num_free += this_free; fprev = &fblk->next; } } total_floats = num_used; total_free_floats = num_free; } /* Put all unmarked intervals on free list */ { register struct interval_block *iblk; struct interval_block **iprev = &interval_block; register int lim = interval_block_index; register int num_free = 0, num_used = 0; interval_free_list = 0; for (iblk = interval_block; iblk; iblk = *iprev) { register int i; int this_free = 0; for (i = 0; i < lim; i++) { if (!iblk->intervals[i].gcmarkbit) { SET_INTERVAL_PARENT (&iblk->intervals[i], interval_free_list); interval_free_list = &iblk->intervals[i]; this_free++; } else { num_used++; iblk->intervals[i].gcmarkbit = 0; } } lim = INTERVAL_BLOCK_SIZE; /* If this block contains only free intervals and we have already seen more than two blocks worth of free intervals then deallocate this block. */ if (this_free == INTERVAL_BLOCK_SIZE && num_free > INTERVAL_BLOCK_SIZE) { *iprev = iblk->next; /* Unhook from the free list. */ interval_free_list = INTERVAL_PARENT (&iblk->intervals[0]); lisp_free (iblk); n_interval_blocks--; } else { num_free += this_free; iprev = &iblk->next; } } total_intervals = num_used; total_free_intervals = num_free; } /* Put all unmarked symbols on free list */ { register struct symbol_block *sblk; struct symbol_block **sprev = &symbol_block; register int lim = symbol_block_index; register int num_free = 0, num_used = 0; symbol_free_list = NULL; for (sblk = symbol_block; sblk; sblk = *sprev) { int this_free = 0; struct Lisp_Symbol *sym = sblk->symbols; struct Lisp_Symbol *end = sym + lim; for (; sym < end; ++sym) { /* Check if the symbol was created during loadup. In such a case it might be pointed to by pure bytecode which we don't trace, so we conservatively assume that it is live. */ int pure_p = PURE_POINTER_P (XSTRING (sym->xname)); if (!sym->gcmarkbit && !pure_p) { sym->next = symbol_free_list; symbol_free_list = sym; #if GC_MARK_STACK symbol_free_list->function = Vdead; #endif ++this_free; } else { ++num_used; if (!pure_p) UNMARK_STRING (XSTRING (sym->xname)); sym->gcmarkbit = 0; } } lim = SYMBOL_BLOCK_SIZE; /* If this block contains only free symbols and we have already seen more than two blocks worth of free symbols then deallocate this block. */ if (this_free == SYMBOL_BLOCK_SIZE && num_free > SYMBOL_BLOCK_SIZE) { *sprev = sblk->next; /* Unhook from the free list. */ symbol_free_list = sblk->symbols[0].next; lisp_free (sblk); n_symbol_blocks--; } else { num_free += this_free; sprev = &sblk->next; } } total_symbols = num_used; total_free_symbols = num_free; } /* Put all unmarked misc's on free list. For a marker, first unchain it from the buffer it points into. */ { register struct marker_block *mblk; struct marker_block **mprev = &marker_block; register int lim = marker_block_index; register int num_free = 0, num_used = 0; marker_free_list = 0; for (mblk = marker_block; mblk; mblk = *mprev) { register int i; int this_free = 0; for (i = 0; i < lim; i++) { if (!mblk->markers[i].u_marker.gcmarkbit) { if (mblk->markers[i].u_marker.type == Lisp_Misc_Marker) unchain_marker (&mblk->markers[i].u_marker); /* Set the type of the freed object to Lisp_Misc_Free. We could leave the type alone, since nobody checks it, but this might catch bugs faster. */ mblk->markers[i].u_marker.type = Lisp_Misc_Free; mblk->markers[i].u_free.chain = marker_free_list; marker_free_list = &mblk->markers[i]; this_free++; } else { num_used++; mblk->markers[i].u_marker.gcmarkbit = 0; } } lim = MARKER_BLOCK_SIZE; /* If this block contains only free markers and we have already seen more than two blocks worth of free markers then deallocate this block. */ if (this_free == MARKER_BLOCK_SIZE && num_free > MARKER_BLOCK_SIZE) { *mprev = mblk->next; /* Unhook from the free list. */ marker_free_list = mblk->markers[0].u_free.chain; lisp_free (mblk); n_marker_blocks--; } else { num_free += this_free; mprev = &mblk->next; } } total_markers = num_used; total_free_markers = num_free; } /* Free all unmarked buffers */ { register struct buffer *buffer = all_buffers, *prev = 0, *next; while (buffer) if (!VECTOR_MARKED_P (buffer)) { if (prev) prev->next = buffer->next; else all_buffers = buffer->next; next = buffer->next; lisp_free (buffer); buffer = next; } else { VECTOR_UNMARK (buffer); UNMARK_BALANCE_INTERVALS (BUF_INTERVALS (buffer)); prev = buffer, buffer = buffer->next; } } /* Free all unmarked vectors */ { register struct Lisp_Vector *vector = all_vectors, *prev = 0, *next; total_vector_size = 0; while (vector) if (!VECTOR_MARKED_P (vector)) { if (prev) prev->next = vector->next; else all_vectors = vector->next; next = vector->next; lisp_free (vector); n_vectors--; vector = next; } else { VECTOR_UNMARK (vector); if (vector->size & PSEUDOVECTOR_FLAG) total_vector_size += (PSEUDOVECTOR_SIZE_MASK & vector->size); else total_vector_size += vector->size; prev = vector, vector = vector->next; } } #ifdef GC_CHECK_STRING_BYTES if (!noninteractive) check_string_bytes (1); #endif } /* Debugging aids. */ DEFUN ("memory-limit", Fmemory_limit, Smemory_limit, 0, 0, 0, doc: /* Return the address of the last byte Emacs has allocated, divided by 1024. This may be helpful in debugging Emacs's memory usage. We divide the value by 1024 to make sure it fits in a Lisp integer. */) () { Lisp_Object end; XSETINT (end, (EMACS_INT) sbrk (0) / 1024); return end; } DEFUN ("memory-use-counts", Fmemory_use_counts, Smemory_use_counts, 0, 0, 0, doc: /* Return a list of counters that measure how much consing there has been. Each of these counters increments for a certain kind of object. The counters wrap around from the largest positive integer to zero. Garbage collection does not decrease them. The elements of the value are as follows: (CONSES FLOATS VECTOR-CELLS SYMBOLS STRING-CHARS MISCS INTERVALS STRINGS) All are in units of 1 = one object consed except for VECTOR-CELLS and STRING-CHARS, which count the total length of objects consed. MISCS include overlays, markers, and some internal types. Frames, windows, buffers, and subprocesses count as vectors (but the contents of a buffer's text do not count here). */) () { Lisp_Object consed[8]; consed[0] = make_number (min (MOST_POSITIVE_FIXNUM, cons_cells_consed)); consed[1] = make_number (min (MOST_POSITIVE_FIXNUM, floats_consed)); consed[2] = make_number (min (MOST_POSITIVE_FIXNUM, vector_cells_consed)); consed[3] = make_number (min (MOST_POSITIVE_FIXNUM, symbols_consed)); consed[4] = make_number (min (MOST_POSITIVE_FIXNUM, string_chars_consed)); consed[5] = make_number (min (MOST_POSITIVE_FIXNUM, misc_objects_consed)); consed[6] = make_number (min (MOST_POSITIVE_FIXNUM, intervals_consed)); consed[7] = make_number (min (MOST_POSITIVE_FIXNUM, strings_consed)); return Flist (8, consed); } int suppress_checking; void die (msg, file, line) const char *msg; const char *file; int line; { fprintf (stderr, "\r\nEmacs fatal error: %s:%d: %s\r\n", file, line, msg); abort (); } /* Initialization */ void init_alloc_once () { /* Used to do Vpurify_flag = Qt here, but Qt isn't set up yet! */ purebeg = PUREBEG; pure_size = PURESIZE; pure_bytes_used = 0; pure_bytes_used_lisp = pure_bytes_used_non_lisp = 0; pure_bytes_used_before_overflow = 0; /* Initialize the list of free aligned blocks. */ free_ablock = NULL; #if GC_MARK_STACK || defined GC_MALLOC_CHECK mem_init (); Vdead = make_pure_string ("DEAD", 4, 4, 0); #endif all_vectors = 0; ignore_warnings = 1; #ifdef DOUG_LEA_MALLOC mallopt (M_TRIM_THRESHOLD, 128*1024); /* trim threshold */ mallopt (M_MMAP_THRESHOLD, 64*1024); /* mmap threshold */ mallopt (M_MMAP_MAX, MMAP_MAX_AREAS); /* max. number of mmap'ed areas */ #endif init_strings (); init_cons (); init_symbol (); init_marker (); init_float (); init_intervals (); #ifdef REL_ALLOC malloc_hysteresis = 32; #else malloc_hysteresis = 0; #endif refill_memory_reserve (); ignore_warnings = 0; gcprolist = 0; byte_stack_list = 0; staticidx = 0; consing_since_gc = 0; gc_cons_threshold = 100000 * sizeof (Lisp_Object); gc_relative_threshold = 0; #ifdef VIRT_ADDR_VARIES malloc_sbrk_unused = 1<<22; /* A large number */ malloc_sbrk_used = 100000; /* as reasonable as any number */ #endif /* VIRT_ADDR_VARIES */ } void init_alloc () { gcprolist = 0; byte_stack_list = 0; #if GC_MARK_STACK #if !defined GC_SAVE_REGISTERS_ON_STACK && !defined GC_SETJMP_WORKS setjmp_tested_p = longjmps_done = 0; #endif #endif Vgc_elapsed = make_float (0.0); gcs_done = 0; } void syms_of_alloc () { DEFVAR_INT ("gc-cons-threshold", &gc_cons_threshold, doc: /* *Number of bytes of consing between garbage collections. Garbage collection can happen automatically once this many bytes have been allocated since the last garbage collection. All data types count. Garbage collection happens automatically only when `eval' is called. By binding this temporarily to a large number, you can effectively prevent garbage collection during a part of the program. See also `gc-cons-percentage'. */); DEFVAR_LISP ("gc-cons-percentage", &Vgc_cons_percentage, doc: /* *Portion of the heap used for allocation. Garbage collection can happen automatically once this portion of the heap has been allocated since the last garbage collection. If this portion is smaller than `gc-cons-threshold', this is ignored. */); Vgc_cons_percentage = make_float (0.1); DEFVAR_INT ("pure-bytes-used", &pure_bytes_used, doc: /* Number of bytes of sharable Lisp data allocated so far. */); DEFVAR_INT ("cons-cells-consed", &cons_cells_consed, doc: /* Number of cons cells that have been consed so far. */); DEFVAR_INT ("floats-consed", &floats_consed, doc: /* Number of floats that have been consed so far. */); DEFVAR_INT ("vector-cells-consed", &vector_cells_consed, doc: /* Number of vector cells that have been consed so far. */); DEFVAR_INT ("symbols-consed", &symbols_consed, doc: /* Number of symbols that have been consed so far. */); DEFVAR_INT ("string-chars-consed", &string_chars_consed, doc: /* Number of string characters that have been consed so far. */); DEFVAR_INT ("misc-objects-consed", &misc_objects_consed, doc: /* Number of miscellaneous objects that have been consed so far. */); DEFVAR_INT ("intervals-consed", &intervals_consed, doc: /* Number of intervals that have been consed so far. */); DEFVAR_INT ("strings-consed", &strings_consed, doc: /* Number of strings that have been consed so far. */); DEFVAR_LISP ("purify-flag", &Vpurify_flag, doc: /* Non-nil means loading Lisp code in order to dump an executable. This means that certain objects should be allocated in shared (pure) space. */); DEFVAR_BOOL ("garbage-collection-messages", &garbage_collection_messages, doc: /* Non-nil means display messages at start and end of garbage collection. */); garbage_collection_messages = 0; DEFVAR_LISP ("post-gc-hook", &Vpost_gc_hook, doc: /* Hook run after garbage collection has finished. */); Vpost_gc_hook = Qnil; Qpost_gc_hook = intern ("post-gc-hook"); staticpro (&Qpost_gc_hook); DEFVAR_LISP ("memory-signal-data", &Vmemory_signal_data, doc: /* Precomputed `signal' argument for memory-full error. */); /* We build this in advance because if we wait until we need it, we might not be able to allocate the memory to hold it. */ Vmemory_signal_data = list2 (Qerror, build_string ("Memory exhausted--use M-x save-some-buffers then exit and restart Emacs")); DEFVAR_LISP ("memory-full", &Vmemory_full, doc: /* Non-nil means Emacs cannot get much more Lisp memory. */); Vmemory_full = Qnil; staticpro (&Qgc_cons_threshold); Qgc_cons_threshold = intern ("gc-cons-threshold"); staticpro (&Qchar_table_extra_slots); Qchar_table_extra_slots = intern ("char-table-extra-slots"); DEFVAR_LISP ("gc-elapsed", &Vgc_elapsed, doc: /* Accumulated time elapsed in garbage collections. The time is in seconds as a floating point value. */); DEFVAR_INT ("gcs-done", &gcs_done, doc: /* Accumulated number of garbage collections done. */); defsubr (&Scons); defsubr (&Slist); defsubr (&Svector); defsubr (&Smake_byte_code); defsubr (&Smake_list); defsubr (&Smake_vector); defsubr (&Smake_char_table); defsubr (&Smake_string); defsubr (&Smake_bool_vector); defsubr (&Smake_symbol); defsubr (&Smake_marker); defsubr (&Spurecopy); defsubr (&Sgarbage_collect); defsubr (&Smemory_limit); defsubr (&Smemory_use_counts); #if GC_MARK_STACK == GC_USE_GCPROS_CHECK_ZOMBIES defsubr (&Sgc_status); #endif } /* arch-tag: 6695ca10-e3c5-4c2c-8bc3-ed26a7dda857 (do not change this comment) */