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/* 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, 2007, 2008, 2009, 2010, 2011, 2012
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 3 of the License, 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. If not, see <http://www.gnu.org/licenses/>. */
#include <config.h>
#include <stdio.h>
#include <limits.h> /* For CHAR_BIT. */
#include <setjmp.h>
#ifdef STDC_HEADERS
#include <stddef.h> /* For offsetof, used by PSEUDOVECSIZE. */
#endif
#ifdef ALLOC_DEBUG
#undef INLINE
#endif
#include <signal.h>
#ifdef HAVE_GTK_AND_PTHREAD
#include <pthread.h>
#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 "character.h"
#include "syssignal.h"
#include "termhooks.h" /* For struct terminal. */
#include <setjmp.h>
/* 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 <unistd.h>
#else
extern POINTER_TYPE *sbrk ();
#endif
#ifdef HAVE_FCNTL_H
#define INCLUDED_FCNTL
#include <fcntl.h>
#endif
#ifndef O_WRONLY
#define O_WRONLY 1
#endif
#ifdef WINDOWSNT
#include <fcntl.h>
#include "w32.h"
#endif
#ifdef DOUG_LEA_MALLOC
#include <malloc.h>
/* 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_equal (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_equal (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)->header.size |= ARRAY_MARK_FLAG)
#define VECTOR_UNMARK(V) ((V)->header.size &= ~ARRAY_MARK_FLAG)
#define VECTOR_MARKED_P(V) (((V)->header.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. */
static 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) / 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. */
static char *stack_copy;
static int stack_copy_size;
/* Non-zero means ignore malloc warnings. Set during initialization.
Currently not used. */
static 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));
static void mark_terminals P_ ((void));
extern void mark_kboards P_ ((void));
extern void mark_ttys 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));
#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,
/* We used to keep separate mem_types for subtypes of vectors such as
process, hash_table, frame, terminal, and window, but we never made
use of the distinction, so it only caused source-code complexity
and runtime slowdown. Minor but pointless. */
MEM_TYPE_VECTORLIKE
};
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 <stdio.h> /* For fprintf. */
#endif
/* A unique object in pure space used to make some Lisp objects
on free lists recognizable in O(1). */
static Lisp_Object Vdead;
#ifdef GC_MALLOC_CHECK
enum mem_type allocated_mem_type;
static 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));
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 *, int));
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 0x640
static Lisp_Object *staticvec[NSTATICS] = {&Vpurify_flag};
/* Index of next unused slot in staticvec. */
static 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
#ifdef SYNC_INPUT
/* When using SYNC_INPUT, we don't call malloc from a signal handler, so
there's no need to block input around malloc. */
#define MALLOC_BLOCK_INPUT ((void)0)
#define MALLOC_UNBLOCK_INPUT ((void)0)
#else
#define MALLOC_BLOCK_INPUT BLOCK_INPUT
#define MALLOC_UNBLOCK_INPUT UNBLOCK_INPUT
#endif
/* Like malloc but check for no memory and block interrupt input.. */
POINTER_TYPE *
xmalloc (size)
size_t size;
{
register POINTER_TYPE *val;
MALLOC_BLOCK_INPUT;
val = (POINTER_TYPE *) malloc (size);
MALLOC_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;
MALLOC_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);
MALLOC_UNBLOCK_INPUT;
if (!val && size) memory_full ();
return val;
}
/* Like free but block interrupt input. */
void
xfree (block)
POINTER_TYPE *block;
{
if (!block)
return;
MALLOC_BLOCK_INPUT;
free (block);
MALLOC_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;
MALLOC_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
MALLOC_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;
{
MALLOC_BLOCK_INPUT;
free (block);
#if GC_MARK_STACK && !defined GC_MALLOC_CHECK
mem_delete (mem_find (block));
#endif
MALLOC_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);
MALLOC_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)
{
MALLOC_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);
MALLOC_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
MALLOC_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);
MALLOC_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));
}
MALLOC_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);
XSETPVECTYPESIZE (b, PVEC_BUFFER,
((sizeof (struct buffer) + sizeof (EMACS_INT) - 1)
/ sizeof (EMACS_INT)));
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
/* When using SYNC_INPUT, we don't call malloc from a signal handler, so
there's no need to block input around malloc. */
#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;
{
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
/* Segfaults on my system. --lorentey */
/* 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 = old_free_hook;
__malloc_hook = old_malloc_hook;
__realloc_hook = old_realloc_hook;
}
#endif /* HAVE_GTK_AND_PTHREAD */
/* Called from main to set up malloc to use our hooks. */
void
uninterrupt_malloc ()
{
#ifdef HAVE_GTK_AND_PTHREAD
#ifdef DOUG_LEA_MALLOC
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);
#else /* !DOUG_LEA_MALLOC */
/* Some systems such as Solaris 2.6 doesn't have a recursive mutex,
and the bundled gmalloc.c doesn't require it. */
pthread_mutex_init (&alloc_mutex, NULL);
#endif /* !DOUG_LEA_MALLOC */
#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. */
static 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. */
static 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); */
MALLOC_BLOCK_INPUT;
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++];
}
MALLOC_UNBLOCK_INPUT;
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 USE_LISP_UNION_TYPE is 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. */
static 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;
empty_unibyte_string = make_pure_string ("", 0, 0, 0);
empty_multibyte_string = make_pure_string ("", 0, 0, 1);
}
#ifdef GC_CHECK_STRING_BYTES
static int check_string_bytes_count;
static void check_string_bytes P_ ((int));
static 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. */
static 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. */
static 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); */
MALLOC_BLOCK_INPUT;
/* 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);
MALLOC_UNBLOCK_INPUT;
/* 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)
{
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);
MALLOC_BLOCK_INPUT;
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 */
mallopt (M_MMAP_MAX, 0);
#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. */
mallopt (M_MMAP_MAX, MMAP_MAX_AREAS);
#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);
MALLOC_UNBLOCK_INPUT;
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 (ASCII_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);
/* No Lisp_Object to trace in there. */
XSETPVECTYPESIZE (XVECTOR (val), PVEC_BOOL_VECTOR, 0);
p = XBOOL_VECTOR (val);
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)
p->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;
if (!length)
return empty_unibyte_string;
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 ();
if (!nbytes)
return empty_multibyte_string;
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. */
static 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. */
static 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); */
MALLOC_BLOCK_INPUT;
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++;
}
MALLOC_UNBLOCK_INPUT;
XFLOAT_INIT (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. */
static int n_cons_blocks;
/* Initialize cons allocation. */
static 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); */
MALLOC_BLOCK_INPUT;
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++;
}
MALLOC_UNBLOCK_INPUT;
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. */
static struct Lisp_Vector *all_vectors;
/* Total number of vector-like objects now in use. */
static 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)
EMACS_INT len;
{
struct Lisp_Vector *p;
size_t nbytes;
MALLOC_BLOCK_INPUT;
#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
/* 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, MEM_TYPE_VECTORLIKE);
#ifdef DOUG_LEA_MALLOC
/* Back to a reasonable maximum of mmap'ed areas. */
mallopt (M_MMAP_MAX, MMAP_MAX_AREAS);
#endif
consing_since_gc += nbytes;
vector_cells_consed += len;
p->header.next.vector = all_vectors;
all_vectors = p;
MALLOC_UNBLOCK_INPUT;
++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);
v->header.size = nslots;
return v;
}
/* Allocate other vector-like structures. */
struct Lisp_Vector *
allocate_pseudovector (memlen, lisplen, tag)
int memlen, lisplen;
EMACS_INT tag;
{
struct Lisp_Vector *v = allocate_vectorlike (memlen);
EMACS_INT i;
/* Only the first lisplen slots will be traced normally by the GC. */
for (i = 0; i < lisplen; ++i)
v->contents[i] = Qnil;
XSETPVECTYPESIZE (v, tag, lisplen);
return v;
}
struct Lisp_Hash_Table *
allocate_hash_table (void)
{
return ALLOCATE_PSEUDOVECTOR (struct Lisp_Hash_Table, count, PVEC_HASH_TABLE);
}
struct window *
allocate_window ()
{
return ALLOCATE_PSEUDOVECTOR(struct window, current_matrix, PVEC_WINDOW);
}
struct terminal *
allocate_terminal ()
{
struct terminal *t = ALLOCATE_PSEUDOVECTOR (struct terminal,
next_terminal, PVEC_TERMINAL);
/* Zero out the non-GC'd fields. FIXME: This should be made unnecessary. */
bzero (&(t->next_terminal),
((char*)(t+1)) - ((char*)&(t->next_terminal)));
return t;
}
struct frame *
allocate_frame ()
{
struct frame *f = ALLOCATE_PSEUDOVECTOR (struct frame,
face_cache, PVEC_FRAME);
/* Zero out the non-GC'd fields. FIXME: This should be made unnecessary. */
bzero (&(f->face_cache),
((char*)(f+1)) - ((char*)&(f->face_cache)));
return f;
}
struct Lisp_Process *
allocate_process ()
{
return ALLOCATE_PSEUDOVECTOR (struct Lisp_Process, pid, PVEC_PROCESS);
}
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 ("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 (nargs > 1 && 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];
}
XSETPVECTYPE (p, PVEC_COMPILED);
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. */
static struct symbol_block *symbol_block;
static int symbol_block_index;
/* List of free symbols. */
static struct Lisp_Symbol *symbol_free_list;
/* Total number of symbol blocks now in use. */
static int n_symbol_blocks;
/* Initialize symbol allocation. */
static 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); */
MALLOC_BLOCK_INPUT;
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++;
}
MALLOC_UNBLOCK_INPUT;
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;
};
static struct marker_block *marker_block;
static int marker_block_index;
static union Lisp_Misc *marker_free_list;
/* Total number of marker blocks now in use. */
static int n_marker_blocks;
static 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); */
MALLOC_BLOCK_INPUT;
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++;
}
MALLOC_UNBLOCK_INPUT;
--total_free_markers;
consing_since_gc += sizeof (union Lisp_Misc);
misc_objects_consed++;
XMISCANY (val)->gcmarkbit = 0;
return val;
}
/* Free a Lisp_Misc object */
void
free_misc (misc)
Lisp_Object misc;
{
XMISCTYPE (misc) = 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 (min_heap_address == NULL || start < min_heap_address)
min_heap_address = start;
if (max_heap_address == NULL || 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_any.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_VECTORLIKE);
}
/* 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 */