/* Block-relocating memory allocator.
- Copyright (C) 1993 Free Software Foundation, Inc.
+ Copyright (C) 1993, 1995, 2000 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 1, or (at your option)
+the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU Emacs is distributed in the hope that it will be useful,
You should have received a copy of the GNU General Public License
along with GNU Emacs; see the file COPYING. If not, write to
-the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
+the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, USA. */
/* NOTES:
Only relocate the blocs necessary for SIZE in r_alloc_sbrk,
rather than all of them. This means allowing for a possible
- hole between the first bloc and the end of malloc storage. */
+ hole between the first bloc and the end of malloc storage. */
#ifdef emacs
#include <config.h>
#include "lisp.h" /* Needed for VALBITS. */
-#undef NULL
-
-/* The important properties of this type are that 1) it's a pointer, and
- 2) arithmetic on it should work as if the size of the object pointed
- to has a size of 1. */
-#if 0 /* Arithmetic on void* is a GCC extension. */
-#ifdef __STDC__
-typedef void *POINTER;
-#else
-
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-typedef char *POINTER;
-
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
#endif
-#endif /* 0 */
-
-/* Unconditionally use char * for this. */
-typedef char *POINTER;
-typedef unsigned long SIZE;
+typedef POINTER_TYPE *POINTER;
+typedef size_t SIZE;
/* Declared in dispnew.c, this version doesn't screw up if regions
overlap. */
+
extern void safe_bcopy ();
-#include "getpagesize.h"
+#ifdef DOUG_LEA_MALLOC
+#define M_TOP_PAD -2
+extern int mallopt ();
+#else /* not DOUG_LEA_MALLOC */
+#ifndef SYSTEM_MALLOC
+extern size_t __malloc_extra_blocks;
+#endif /* SYSTEM_MALLOC */
+#endif /* not DOUG_LEA_MALLOC */
-#else /* Not emacs. */
+#else /* not emacs */
#include <stddef.h>
#include <unistd.h>
#include <malloc.h>
-#include <string.h>
#define safe_bcopy(x, y, z) memmove (y, x, z)
+#define bzero(x, len) memset (x, 0, len)
+
+#endif /* not emacs */
-#endif /* emacs. */
+
+#include "getpagesize.h"
#define NIL ((POINTER) 0)
machines, the dumping procedure makes all static variables
read-only. On these machines, the word static is #defined to be
the empty string, meaning that r_alloc_initialized becomes an
- automatic variable, and loses its value each time Emacs is started up. */
+ automatic variable, and loses its value each time Emacs is started
+ up. */
+
static int r_alloc_initialized = 0;
static void r_alloc_init ();
+
\f
/* Declarations for working with the malloc, ralloc, and system breaks. */
-/* Function to set the real break value. */
-static POINTER (*real_morecore) ();
+/* Function to set the real break value. */
+POINTER (*real_morecore) ();
-/* The break value, as seen by malloc (). */
+/* The break value, as seen by malloc. */
static POINTER virtual_break_value;
-/* The break value, viewed by the relocatable blocs. */
+/* The address of the end of the last data in use by ralloc,
+ including relocatable blocs as well as malloc data. */
static POINTER break_value;
/* This is the size of a page. We round memory requests to this boundary. */
static int extra_bytes;
/* Macros for rounding. Note that rounding to any value is possible
- by changing the definition of PAGE. */
+ by changing the definition of PAGE. */
#define PAGE (getpagesize ())
#define ALIGNED(addr) (((unsigned long int) (addr) & (page_size - 1)) == 0)
#define ROUNDUP(size) (((unsigned long int) (size) + page_size - 1) \
#define MEM_ALIGN sizeof(double)
#define MEM_ROUNDUP(addr) (((unsigned long int)(addr) + MEM_ALIGN - 1) \
& ~(MEM_ALIGN - 1))
+
+/* The hook `malloc' uses for the function which gets more space
+ from the system. */
+
+#ifndef SYSTEM_MALLOC
+extern POINTER (*__morecore) ();
+#endif
+
+
\f
-/* Data structures of heaps and blocs */
+/***********************************************************************
+ Implementation using sbrk
+ ***********************************************************************/
+
+/* Data structures of heaps and blocs. */
+
+/* The relocatable objects, or blocs, and the malloc data
+ both reside within one or more heaps.
+ Each heap contains malloc data, running from `start' to `bloc_start',
+ and relocatable objects, running from `bloc_start' to `free'.
+
+ Relocatable objects may relocate within the same heap
+ or may move into another heap; the heaps themselves may grow
+ but they never move.
+
+ We try to make just one heap and make it larger as necessary.
+ But sometimes we can't do that, because we can't get contiguous
+ space to add onto the heap. When that happens, we start a new heap. */
+
typedef struct heap
{
struct heap *next;
struct heap *prev;
+ /* Start of memory range of this heap. */
POINTER start;
+ /* End of memory range of this heap. */
POINTER end;
- POINTER bloc_start; /* start of relocatable blocs */
+ /* Start of relocatable data in this heap. */
+ POINTER bloc_start;
+ /* Start of unused space in this heap. */
+ POINTER free;
+ /* First bloc in this heap. */
+ struct bp *first_bloc;
+ /* Last bloc in this heap. */
+ struct bp *last_bloc;
} *heap_ptr;
#define NIL_HEAP ((heap_ptr) 0)
#define HEAP_PTR_SIZE (sizeof (struct heap))
-/* Head and tail of the list of heaps. */
+/* This is the first heap object.
+ If we need additional heap objects, each one resides at the beginning of
+ the space it covers. */
+static struct heap heap_base;
+
+/* Head and tail of the list of heaps. */
static heap_ptr first_heap, last_heap;
/* These structures are allocated in the malloc arena.
The linked list is kept in order of increasing '.data' members.
The data blocks abut each other; if b->next is non-nil, then
- b->data + b->size == b->next->data. */
+ b->data + b->size == b->next->data.
+
+ An element with variable==NIL denotes a freed block, which has not yet
+ been collected. They may only appear while r_alloc_freeze > 0, and will be
+ freed when the arena is thawed. Currently, these blocs are not reusable,
+ while the arena is frozen. Very inefficient. */
+
typedef struct bp
{
struct bp *next;
POINTER *variable;
POINTER data;
SIZE size;
- POINTER new_data; /* tmporarily used for relocation */
+ POINTER new_data; /* temporarily used for relocation */
+ struct heap *heap; /* Heap this bloc is in. */
} *bloc_ptr;
#define NIL_BLOC ((bloc_ptr) 0)
#define BLOC_PTR_SIZE (sizeof (struct bp))
-/* Head and tail of the list of relocatable blocs. */
+/* Head and tail of the list of relocatable blocs. */
static bloc_ptr first_bloc, last_bloc;
+static int use_relocatable_buffers;
+
+/* If >0, no relocation whatsoever takes place. */
+static int r_alloc_freeze_level;
+
\f
/* Functions to get and return memory from the system. */
-/* Obtain SIZE bytes of space starting at ADDRESS in a heap.
+/* Find the heap that ADDRESS falls within. */
+
+static heap_ptr
+find_heap (address)
+ POINTER address;
+{
+ heap_ptr heap;
+
+ for (heap = last_heap; heap; heap = heap->prev)
+ {
+ if (heap->start <= address && address <= heap->end)
+ return heap;
+ }
+
+ return NIL_HEAP;
+}
+
+/* Find SIZE bytes of space in a heap.
+ Try to get them at ADDRESS (which must fall within some heap's range)
+ if we can get that many within one heap.
+
If enough space is not presently available in our reserve, this means
- getting more page-aligned space from the system. If the retuned space
- is not contiguos to the last heap, allocate a new heap, and append it
- to the heap list.
+ getting more page-aligned space from the system. If the returned space
+ is not contiguous to the last heap, allocate a new heap, and append it
+
+ obtain does not try to keep track of whether space is in use
+ or not in use. It just returns the address of SIZE bytes that
+ fall within a single heap. If you call obtain twice in a row
+ with the same arguments, you typically get the same value.
+ to the heap list. It's the caller's responsibility to keep
+ track of what space is in use.
Return the address of the space if all went well, or zero if we couldn't
allocate the memory. */
+
static POINTER
obtain (address, size)
POINTER address;
heap_ptr heap;
SIZE already_available;
+ /* Find the heap that ADDRESS falls within. */
for (heap = last_heap; heap; heap = heap->prev)
{
if (heap->start <= address && address <= heap->end)
}
if (! heap)
- abort();
+ abort ();
- while (heap && address + size > heap->end)
+ /* If we can't fit SIZE bytes in that heap,
+ try successive later heaps. */
+ while (heap && (char *) address + size > (char *) heap->end)
{
heap = heap->next;
if (heap == NIL_HEAP)
address = heap->bloc_start;
}
+ /* If we can't fit them within any existing heap,
+ get more space. */
if (heap == NIL_HEAP)
{
POINTER new = (*real_morecore)(0);
if (new != last_heap->end)
{
- /* Someone else called sbrk(). */
- heap_ptr new_heap = (heap_ptr) MEM_ROUNDUP(new);
- POINTER bloc_start = (POINTER) MEM_ROUNDUP((POINTER)(new_heap + 1));
+ /* Someone else called sbrk. Make a new heap. */
+
+ heap_ptr new_heap = (heap_ptr) MEM_ROUNDUP (new);
+ POINTER bloc_start = (POINTER) MEM_ROUNDUP ((POINTER)(new_heap + 1));
- if ((*real_morecore) (bloc_start - new) != new)
+ if ((*real_morecore) ((char *) bloc_start - (char *) new) != new)
return 0;
new_heap->start = new;
new_heap->end = bloc_start;
new_heap->bloc_start = bloc_start;
+ new_heap->free = bloc_start;
new_heap->next = NIL_HEAP;
new_heap->prev = last_heap;
+ new_heap->first_bloc = NIL_BLOC;
+ new_heap->last_bloc = NIL_BLOC;
last_heap->next = new_heap;
last_heap = new_heap;
already_available = 0;
}
- /* Get some extra, so we can come here less often. */
+ /* Add space to the last heap (which we may have just created).
+ Get some extra, so we can come here less often. */
+
get = size + extra_bytes - already_available;
- get = (char *) ROUNDUP((char *)last_heap->end + get)
+ get = (char *) ROUNDUP ((char *)last_heap->end + get)
- (char *) last_heap->end;
if ((*real_morecore) (get) != last_heap->end)
return 0;
- last_heap->end += get;
+ last_heap->end = (char *) last_heap->end + get;
}
return address;
}
-/* If the last heap has a excessive space, return it to the system. */
+/* Return unused heap space to the system
+ if there is a lot of unused space now.
+ This can make the last heap smaller;
+ it can also eliminate the last heap entirely. */
+
static void
relinquish ()
{
register heap_ptr h;
int excess = 0;
+ /* Add the amount of space beyond break_value
+ in all heaps which have extend beyond break_value at all. */
+
for (h = last_heap; h && break_value < h->end; h = h->prev)
{
excess += (char *) h->end - (char *) ((break_value < h->bloc_start)
if ((char *)last_heap->end - (char *)last_heap->bloc_start <= excess)
{
- /* Return the last heap with its header to the system */
+ /* This heap should have no blocs in it. */
+ if (last_heap->first_bloc != NIL_BLOC
+ || last_heap->last_bloc != NIL_BLOC)
+ abort ();
+
+ /* Return the last heap, with its header, to the system. */
excess = (char *)last_heap->end - (char *)last_heap->start;
last_heap = last_heap->prev;
last_heap->next = NIL_HEAP;
else
{
excess = (char *) last_heap->end
- - (char *) ROUNDUP((char *)last_heap->end - excess);
- last_heap->end -= excess;
+ - (char *) ROUNDUP ((char *)last_heap->end - excess);
+ last_heap->end = (char *) last_heap->end - excess;
}
if ((*real_morecore) (- excess) == 0)
- abort ();
+ {
+ /* If the system didn't want that much memory back, adjust
+ the end of the last heap to reflect that. This can occur
+ if break_value is still within the original data segment. */
+ last_heap->end = (char *) last_heap->end + excess;
+ /* Make sure that the result of the adjustment is accurate.
+ It should be, for the else clause above; the other case,
+ which returns the entire last heap to the system, seems
+ unlikely to trigger this mode of failure. */
+ if (last_heap->end != (*real_morecore) (0))
+ abort ();
+ }
}
}
+
+/* Return the total size in use by relocating allocator,
+ above where malloc gets space. */
+
+long
+r_alloc_size_in_use ()
+{
+ return (char *) break_value - (char *) virtual_break_value;
+}
\f
/* The meat - allocating, freeing, and relocating blocs. */
/* Find the bloc referenced by the address in PTR. Returns a pointer
- to that block. */
+ to that block. */
static bloc_ptr
find_bloc (ptr)
SIZE size;
{
register bloc_ptr new_bloc;
+ register heap_ptr heap;
if (! (new_bloc = (bloc_ptr) malloc (BLOC_PTR_SIZE))
|| ! (new_bloc->data = obtain (break_value, size)))
return 0;
}
- break_value = new_bloc->data + size;
+ break_value = (char *) new_bloc->data + size;
new_bloc->size = size;
new_bloc->next = NIL_BLOC;
new_bloc->variable = (POINTER *) NIL;
new_bloc->new_data = 0;
+ /* Record in the heap that this space is in use. */
+ heap = find_heap (new_bloc->data);
+ heap->free = break_value;
+
+ /* Maintain the correspondence between heaps and blocs. */
+ new_bloc->heap = heap;
+ heap->last_bloc = new_bloc;
+ if (heap->first_bloc == NIL_BLOC)
+ heap->first_bloc = new_bloc;
+
+ /* Put this bloc on the doubly-linked list of blocs. */
if (first_bloc)
{
new_bloc->prev = last_bloc;
return new_bloc;
}
-
-/* Calculate new locations of blocs in the list begining with BLOC,
- whose spaces is started at ADDRESS in HEAP. If enough space is
- not presently available in our reserve, obtain() is called for
+\f
+/* Calculate new locations of blocs in the list beginning with BLOC,
+ relocating it to start at ADDRESS, in heap HEAP. If enough space is
+ not presently available in our reserve, call obtain for
more space.
- Do not touch the contents of blocs or break_value. */
+ Store the new location of each bloc in its new_data field.
+ Do not touch the contents of blocs or break_value. */
static int
relocate_blocs (bloc, heap, address)
{
register bloc_ptr b = bloc;
+ /* No need to ever call this if arena is frozen, bug somewhere! */
+ if (r_alloc_freeze_level)
+ abort();
+
while (b)
{
- while (heap && address + b->size > heap->end)
+ /* If bloc B won't fit within HEAP,
+ move to the next heap and try again. */
+ while (heap && (char *) address + b->size > (char *) heap->end)
{
heap = heap->next;
if (heap == NIL_HEAP)
address = heap->bloc_start;
}
+ /* If BLOC won't fit in any heap,
+ get enough new space to hold BLOC and all following blocs. */
if (heap == NIL_HEAP)
{
register bloc_ptr tb = b;
register SIZE s = 0;
+ /* Add up the size of all the following blocs. */
while (tb != NIL_BLOC)
{
- s += tb->size;
+ if (tb->variable)
+ s += tb->size;
+
tb = tb->next;
}
- if (! (address = obtain(address, s)))
+ /* Get that space. */
+ address = obtain (address, s);
+ if (address == 0)
return 0;
heap = last_heap;
}
+ /* Record the new address of this bloc
+ and update where the next bloc can start. */
b->new_data = address;
- address += b->size;
+ if (b->variable)
+ address = (char *) address + b->size;
b = b->next;
}
return 1;
}
-/* Resize BLOC to SIZE bytes. */
+/* Reorder the bloc BLOC to go before bloc BEFORE in the doubly linked list.
+ This is necessary if we put the memory of space of BLOC
+ before that of BEFORE. */
+
+static void
+reorder_bloc (bloc, before)
+ bloc_ptr bloc, before;
+{
+ bloc_ptr prev, next;
+
+ /* Splice BLOC out from where it is. */
+ prev = bloc->prev;
+ next = bloc->next;
+
+ if (prev)
+ prev->next = next;
+ if (next)
+ next->prev = prev;
+
+ /* Splice it in before BEFORE. */
+ prev = before->prev;
+
+ if (prev)
+ prev->next = bloc;
+ bloc->prev = prev;
+
+ before->prev = bloc;
+ bloc->next = before;
+}
+\f
+/* Update the records of which heaps contain which blocs, starting
+ with heap HEAP and bloc BLOC. */
+
+static void
+update_heap_bloc_correspondence (bloc, heap)
+ bloc_ptr bloc;
+ heap_ptr heap;
+{
+ register bloc_ptr b;
+
+ /* Initialize HEAP's status to reflect blocs before BLOC. */
+ if (bloc != NIL_BLOC && bloc->prev != NIL_BLOC && bloc->prev->heap == heap)
+ {
+ /* The previous bloc is in HEAP. */
+ heap->last_bloc = bloc->prev;
+ heap->free = (char *) bloc->prev->data + bloc->prev->size;
+ }
+ else
+ {
+ /* HEAP contains no blocs before BLOC. */
+ heap->first_bloc = NIL_BLOC;
+ heap->last_bloc = NIL_BLOC;
+ heap->free = heap->bloc_start;
+ }
+
+ /* Advance through blocs one by one. */
+ for (b = bloc; b != NIL_BLOC; b = b->next)
+ {
+ /* Advance through heaps, marking them empty,
+ till we get to the one that B is in. */
+ while (heap)
+ {
+ if (heap->bloc_start <= b->data && b->data <= heap->end)
+ break;
+ heap = heap->next;
+ /* We know HEAP is not null now,
+ because there has to be space for bloc B. */
+ heap->first_bloc = NIL_BLOC;
+ heap->last_bloc = NIL_BLOC;
+ heap->free = heap->bloc_start;
+ }
+
+ /* Update HEAP's status for bloc B. */
+ heap->free = (char *) b->data + b->size;
+ heap->last_bloc = b;
+ if (heap->first_bloc == NIL_BLOC)
+ heap->first_bloc = b;
+
+ /* Record that B is in HEAP. */
+ b->heap = heap;
+ }
+
+ /* If there are any remaining heaps and no blocs left,
+ mark those heaps as empty. */
+ heap = heap->next;
+ while (heap)
+ {
+ heap->first_bloc = NIL_BLOC;
+ heap->last_bloc = NIL_BLOC;
+ heap->free = heap->bloc_start;
+ heap = heap->next;
+ }
+}
+\f
+/* Resize BLOC to SIZE bytes. This relocates the blocs
+ that come after BLOC in memory. */
+
static int
resize_bloc (bloc, size)
bloc_ptr bloc;
POINTER address;
SIZE old_size;
+ /* No need to ever call this if arena is frozen, bug somewhere! */
+ if (r_alloc_freeze_level)
+ abort();
+
if (bloc == NIL_BLOC || size == bloc->size)
return 1;
}
if (heap == NIL_HEAP)
- abort();
+ abort ();
old_size = bloc->size;
bloc->size = size;
- /* Note that bloc could be moved into the previous heap. */
- address = bloc->prev ? bloc->prev->data + bloc->prev->size
- : first_heap->bloc_start;
+ /* Note that bloc could be moved into the previous heap. */
+ address = (bloc->prev ? (char *) bloc->prev->data + bloc->prev->size
+ : (char *) first_heap->bloc_start);
while (heap)
{
if (heap->bloc_start <= address && address <= heap->end)
{
for (b = last_bloc; b != bloc; b = b->prev)
{
- safe_bcopy (b->data, b->new_data, b->size);
- *b->variable = b->data = b->new_data;
+ if (!b->variable)
+ {
+ b->size = 0;
+ b->data = b->new_data;
+ }
+ else
+ {
+ safe_bcopy (b->data, b->new_data, b->size);
+ *b->variable = b->data = b->new_data;
+ }
+ }
+ if (!bloc->variable)
+ {
+ bloc->size = 0;
+ bloc->data = bloc->new_data;
+ }
+ else
+ {
+ safe_bcopy (bloc->data, bloc->new_data, old_size);
+ bzero ((char *) bloc->new_data + old_size, size - old_size);
+ *bloc->variable = bloc->data = bloc->new_data;
}
- safe_bcopy (bloc->data, bloc->new_data, old_size);
- bzero (bloc->new_data + old_size, size - old_size);
- *bloc->variable = bloc->data = bloc->new_data;
}
else
{
for (b = bloc; b != NIL_BLOC; b = b->next)
{
- safe_bcopy (b->data, b->new_data, b->size);
- *b->variable = b->data = b->new_data;
+ if (!b->variable)
+ {
+ b->size = 0;
+ b->data = b->new_data;
+ }
+ else
+ {
+ safe_bcopy (b->data, b->new_data, b->size);
+ *b->variable = b->data = b->new_data;
+ }
}
}
- break_value = last_bloc ? last_bloc->data + last_bloc->size
- : first_heap->bloc_start;
+ update_heap_bloc_correspondence (bloc, heap);
+
+ break_value = (last_bloc ? (char *) last_bloc->data + last_bloc->size
+ : (char *) first_heap->bloc_start);
return 1;
}
-
-/* Free BLOC from the chain of blocs, relocating any blocs above it
- and returning BLOC->size bytes to the free area. */
+\f
+/* Free BLOC from the chain of blocs, relocating any blocs above it.
+ This may return space to the system. */
static void
free_bloc (bloc)
bloc_ptr bloc;
{
+ heap_ptr heap = bloc->heap;
+
+ if (r_alloc_freeze_level)
+ {
+ bloc->variable = (POINTER *) NIL;
+ return;
+ }
+
resize_bloc (bloc, 0);
if (bloc == first_bloc && bloc == last_bloc)
bloc->prev->next = bloc->next;
}
+ /* Update the records of which blocs are in HEAP. */
+ if (heap->first_bloc == bloc)
+ {
+ if (bloc->next != 0 && bloc->next->heap == heap)
+ heap->first_bloc = bloc->next;
+ else
+ heap->first_bloc = heap->last_bloc = NIL_BLOC;
+ }
+ if (heap->last_bloc == bloc)
+ {
+ if (bloc->prev != 0 && bloc->prev->heap == heap)
+ heap->last_bloc = bloc->prev;
+ else
+ heap->first_bloc = heap->last_bloc = NIL_BLOC;
+ }
+
relinquish ();
free (bloc);
}
\f
/* Interface routines. */
-static int use_relocatable_buffers;
-static int r_alloc_freeze_level;
-
/* Obtain SIZE bytes of storage from the free pool, or the system, as
necessary. If relocatable blocs are in use, this means relocating
them. This function gets plugged into the GNU malloc's __morecore
register bloc_ptr b;
POINTER address;
+ if (! r_alloc_initialized)
+ r_alloc_init ();
+
if (! use_relocatable_buffers)
return (*real_morecore) (size);
if (size > 0)
{
- /* Allocate a page-aligned space. GNU malloc would reclaim an
- extra space if we passed an unaligned one. But we could
- not always find a space which is contiguos to the previous. */
+ /* Allocate a page-aligned space. GNU malloc would reclaim an
+ extra space if we passed an unaligned one. But we could
+ not always find a space which is contiguous to the previous. */
POINTER new_bloc_start;
heap_ptr h = first_heap;
- SIZE get = ROUNDUP(size);
+ SIZE get = ROUNDUP (size);
- address = (POINTER) ROUNDUP(virtual_break_value);
+ address = (POINTER) ROUNDUP (virtual_break_value);
- /* Search the list upward for a heap which is large enough. */
- while ((char *) h->end < (char *) MEM_ROUNDUP((char *)address + get))
+ /* Search the list upward for a heap which is large enough. */
+ while ((char *) h->end < (char *) MEM_ROUNDUP ((char *)address + get))
{
h = h->next;
if (h == NIL_HEAP)
break;
- address = (POINTER) ROUNDUP(h->start);
+ address = (POINTER) ROUNDUP (h->start);
}
- /* If not found, obatin more space. */
+ /* If not found, obtain more space. */
if (h == NIL_HEAP)
{
get += extra_bytes + page_size;
- if (r_alloc_freeze_level > 0 || ! obtain(address, get))
+ if (! obtain (address, get))
return 0;
if (first_heap == last_heap)
- address = (POINTER) ROUNDUP(virtual_break_value);
+ address = (POINTER) ROUNDUP (virtual_break_value);
else
- address = (POINTER) ROUNDUP(last_heap->start);
+ address = (POINTER) ROUNDUP (last_heap->start);
h = last_heap;
}
- new_bloc_start = (POINTER) MEM_ROUNDUP((char *)address + get);
+ new_bloc_start = (POINTER) MEM_ROUNDUP ((char *)address + get);
if (first_heap->bloc_start < new_bloc_start)
{
- /* Move all blocs upward. */
- if (r_alloc_freeze_level > 0
- || ! relocate_blocs (first_bloc, h, new_bloc_start))
+ /* This is no clean solution - no idea how to do it better. */
+ if (r_alloc_freeze_level)
+ return NIL;
+
+ /* There is a bug here: if the above obtain call succeeded, but the
+ relocate_blocs call below does not succeed, we need to free
+ the memory that we got with obtain. */
+
+ /* Move all blocs upward. */
+ if (! relocate_blocs (first_bloc, h, new_bloc_start))
return 0;
/* Note that (POINTER)(h+1) <= new_bloc_start since
get >= page_size, so the following does not destroy the heap
- header. */
+ header. */
for (b = last_bloc; b != NIL_BLOC; b = b->prev)
{
safe_bcopy (b->data, b->new_data, b->size);
}
h->bloc_start = new_bloc_start;
- }
+ update_heap_bloc_correspondence (first_bloc, h);
+ }
if (h != first_heap)
{
/* Give up managing heaps below the one the new
- virtual_break_value points to. */
+ virtual_break_value points to. */
first_heap->prev = NIL_HEAP;
first_heap->next = h->next;
first_heap->start = h->start;
first_heap->end = h->end;
+ first_heap->free = h->free;
+ first_heap->first_bloc = h->first_bloc;
+ first_heap->last_bloc = h->last_bloc;
first_heap->bloc_start = h->bloc_start;
if (first_heap->next)
{
excess -= extra_bytes;
first_heap->bloc_start
- = (POINTER) MEM_ROUNDUP((char *)first_heap->bloc_start - excess);
+ = (POINTER) MEM_ROUNDUP ((char *)first_heap->bloc_start - excess);
- relocate_blocs(first_bloc, first_heap, first_heap->bloc_start);
+ relocate_blocs (first_bloc, first_heap, first_heap->bloc_start);
for (b = first_bloc; b != NIL_BLOC; b = b->next)
{
}
virtual_break_value = (POINTER) ((char *)address + size);
- break_value = last_bloc ? last_bloc->data + last_bloc->size
- : first_heap->bloc_start;
+ break_value = (last_bloc
+ ? (char *) last_bloc->data + last_bloc->size
+ : (char *) first_heap->bloc_start);
if (size < 0)
- relinquish();
+ relinquish ();
return address;
}
+
/* Allocate a relocatable bloc of storage of size SIZE. A pointer to
the data is returned in *PTR. PTR is thus the address of some variable
which will use the data area.
+ The allocation of 0 bytes is valid.
+ In case r_alloc_freeze is set, a best fit of unused blocs could be done
+ before allocating a new area. Not yet done.
+
If we can't allocate the necessary memory, set *PTR to zero, and
return zero. */
if (! r_alloc_initialized)
r_alloc_init ();
- new_bloc = get_bloc (MEM_ROUNDUP(size));
+ new_bloc = get_bloc (MEM_ROUNDUP (size));
if (new_bloc)
{
new_bloc->variable = ptr;
{
register bloc_ptr dead_bloc;
+ if (! r_alloc_initialized)
+ r_alloc_init ();
+
dead_bloc = find_bloc (ptr);
if (dead_bloc == NIL_BLOC)
abort ();
free_bloc (dead_bloc);
*ptr = 0;
+
+#ifdef emacs
+ refill_memory_reserve ();
+#endif
}
/* Given a pointer at address PTR to relocatable data, resize it to SIZE.
SIZE is less than or equal to the current bloc size, in which case
do nothing.
+ In case r_alloc_freeze is set, a new bloc is allocated, and the
+ memory copied to it. Not very efficient. We could traverse the
+ bloc_list for a best fit of free blocs first.
+
Change *PTR to reflect the new bloc, and return this value.
If more memory cannot be allocated, then leave *PTR unchanged, and
{
register bloc_ptr bloc;
+ if (! r_alloc_initialized)
+ r_alloc_init ();
+
+ if (!*ptr)
+ return r_alloc (ptr, size);
+ if (!size)
+ {
+ r_alloc_free (ptr);
+ return r_alloc (ptr, 0);
+ }
+
bloc = find_bloc (ptr);
if (bloc == NIL_BLOC)
abort ();
- if (size <= bloc->size)
- /* Wouldn't it be useful to actually resize the bloc here? */
- return *ptr;
-
- if (! resize_bloc (bloc, MEM_ROUNDUP(size)))
- return 0;
-
+ if (size < bloc->size)
+ {
+ /* Wouldn't it be useful to actually resize the bloc here? */
+ /* I think so too, but not if it's too expensive... */
+ if ((bloc->size - MEM_ROUNDUP (size) >= page_size)
+ && r_alloc_freeze_level == 0)
+ {
+ resize_bloc (bloc, MEM_ROUNDUP (size));
+ /* Never mind if this fails, just do nothing... */
+ /* It *should* be infallible! */
+ }
+ }
+ else if (size > bloc->size)
+ {
+ if (r_alloc_freeze_level)
+ {
+ bloc_ptr new_bloc;
+ new_bloc = get_bloc (MEM_ROUNDUP (size));
+ if (new_bloc)
+ {
+ new_bloc->variable = ptr;
+ *ptr = new_bloc->data;
+ bloc->variable = (POINTER *) NIL;
+ }
+ else
+ return NIL;
+ }
+ else
+ {
+ if (! resize_bloc (bloc, MEM_ROUNDUP (size)))
+ return NIL;
+ }
+ }
return *ptr;
}
of non-relocatable heap if possible. The relocatable blocs are
guaranteed to hold still until thawed, even if this means that
malloc must return a null pointer. */
+
void
r_alloc_freeze (size)
long size;
{
+ if (! r_alloc_initialized)
+ r_alloc_init ();
+
/* If already frozen, we can't make any more room, so don't try. */
if (r_alloc_freeze_level > 0)
size = 0;
void
r_alloc_thaw ()
{
+
+ if (! r_alloc_initialized)
+ r_alloc_init ();
+
if (--r_alloc_freeze_level < 0)
abort ();
+
+ /* This frees all unused blocs. It is not too inefficient, as the resize
+ and bcopy is done only once. Afterwards, all unreferenced blocs are
+ already shrunk to zero size. */
+ if (!r_alloc_freeze_level)
+ {
+ bloc_ptr *b = &first_bloc;
+ while (*b)
+ if (!(*b)->variable)
+ free_bloc (*b);
+ else
+ b = &(*b)->next;
+ }
+}
+
+
+#if defined (emacs) && defined (DOUG_LEA_MALLOC)
+
+/* Reinitialize the morecore hook variables after restarting a dumped
+ Emacs. This is needed when using Doug Lea's malloc from GNU libc. */
+void
+r_alloc_reinit ()
+{
+ /* Only do this if the hook has been reset, so that we don't get an
+ infinite loop, in case Emacs was linked statically. */
+ if (__morecore != r_alloc_sbrk)
+ {
+ real_morecore = __morecore;
+ __morecore = r_alloc_sbrk;
+ }
+}
+
+#endif /* emacs && DOUG_LEA_MALLOC */
+
+#ifdef DEBUG
+
+#include <assert.h>
+
+void
+r_alloc_check ()
+{
+ int found = 0;
+ heap_ptr h, ph = 0;
+ bloc_ptr b, pb = 0;
+
+ if (!r_alloc_initialized)
+ return;
+
+ assert (first_heap);
+ assert (last_heap->end <= (POINTER) sbrk (0));
+ assert ((POINTER) first_heap < first_heap->start);
+ assert (first_heap->start <= virtual_break_value);
+ assert (virtual_break_value <= first_heap->end);
+
+ for (h = first_heap; h; h = h->next)
+ {
+ assert (h->prev == ph);
+ assert ((POINTER) ROUNDUP (h->end) == h->end);
+#if 0 /* ??? The code in ralloc.c does not really try to ensure
+ the heap start has any sort of alignment.
+ Perhaps it should. */
+ assert ((POINTER) MEM_ROUNDUP (h->start) == h->start);
+#endif
+ assert ((POINTER) MEM_ROUNDUP (h->bloc_start) == h->bloc_start);
+ assert (h->start <= h->bloc_start && h->bloc_start <= h->end);
+
+ if (ph)
+ {
+ assert (ph->end < h->start);
+ assert (h->start <= (POINTER)h && (POINTER)(h+1) <= h->bloc_start);
+ }
+
+ if (h->bloc_start <= break_value && break_value <= h->end)
+ found = 1;
+
+ ph = h;
+ }
+
+ assert (found);
+ assert (last_heap == ph);
+
+ for (b = first_bloc; b; b = b->next)
+ {
+ assert (b->prev == pb);
+ assert ((POINTER) MEM_ROUNDUP (b->data) == b->data);
+ assert ((SIZE) MEM_ROUNDUP (b->size) == b->size);
+
+ ph = 0;
+ for (h = first_heap; h; h = h->next)
+ {
+ if (h->bloc_start <= b->data && b->data + b->size <= h->end)
+ break;
+ ph = h;
+ }
+
+ assert (h);
+
+ if (pb && pb->data + pb->size != b->data)
+ {
+ assert (ph && b->data == h->bloc_start);
+ while (ph)
+ {
+ if (ph->bloc_start <= pb->data
+ && pb->data + pb->size <= ph->end)
+ {
+ assert (pb->data + pb->size + b->size > ph->end);
+ break;
+ }
+ else
+ {
+ assert (ph->bloc_start + b->size > ph->end);
+ }
+ ph = ph->prev;
+ }
+ }
+ pb = b;
+ }
+
+ assert (last_bloc == pb);
+
+ if (last_bloc)
+ assert (last_bloc->data + last_bloc->size == break_value);
+ else
+ assert (first_heap->bloc_start == break_value);
}
+
+#endif /* DEBUG */
+
+
\f
-/* The hook `malloc' uses for the function which gets more space
- from the system. */
-extern POINTER (*__morecore) ();
+/***********************************************************************
+ Initialization
+ ***********************************************************************/
-/* Initialize various things for memory allocation. */
+/* Initialize various things for memory allocation. */
static void
r_alloc_init ()
{
- static struct heap heap_base;
- POINTER end;
-
if (r_alloc_initialized)
return;
-
r_alloc_initialized = 1;
+
+ page_size = PAGE;
+#ifndef SYSTEM_MALLOC
real_morecore = __morecore;
__morecore = r_alloc_sbrk;
if (break_value == NIL)
abort ();
- page_size = PAGE;
extra_bytes = ROUNDUP (50000);
+#endif
+
+#ifdef DOUG_LEA_MALLOC
+ mallopt (M_TOP_PAD, 64 * 4096);
+#else
+#ifndef SYSTEM_MALLOC
+ /* Give GNU malloc's morecore some hysteresis
+ so that we move all the relocatable blocks much less often. */
+ __malloc_extra_blocks = 64;
+#endif
+#endif
+#ifndef SYSTEM_MALLOC
first_heap->end = (POINTER) ROUNDUP (first_heap->start);
/* The extra call to real_morecore guarantees that the end of the
not really the page size of the system running the binary in
which page_size is stored. This allows a binary to be built on a
system with one page size and run on a system with a smaller page
- size. */
- (*real_morecore) (first_heap->end - first_heap->start);
+ size. */
+ (*real_morecore) ((char *) first_heap->end - (char *) first_heap->start);
/* Clear the rest of the last page; this memory is in our address space
even though it is after the sbrk value. */
/* Doubly true, with the additional call that explicitly adds the
rest of that page to the address space. */
- bzero (first_heap->start, first_heap->end - first_heap->start);
+ bzero (first_heap->start,
+ (char *) first_heap->end - (char *) first_heap->start);
virtual_break_value = break_value = first_heap->bloc_start = first_heap->end;
+#endif
+
use_relocatable_buffers = 1;
}
-#ifdef DEBUG
-#include <assert.h>
-
-int
-r_alloc_check ()
-{
- int found = 0;
- heap_ptr h, ph = 0;
- bloc_ptr b, pb = 0;
-
- if (!r_alloc_initialized)
- return;
-
- assert(first_heap);
- assert(last_heap->end <= (POINTER) sbrk(0));
- assert((POINTER) first_heap < first_heap->start);
- assert(first_heap->start <= virtual_break_value);
- assert(virtual_break_value <= first_heap->end);
-
- for (h = first_heap; h; h = h->next)
- {
- assert(h->prev == ph);
- assert((POINTER) ROUNDUP(h->end) == h->end);
- assert((POINTER) MEM_ROUNDUP(h->start) == h->start);
- assert((POINTER) MEM_ROUNDUP(h->bloc_start) == h->bloc_start);
- assert(h->start <= h->bloc_start && h->bloc_start <= h->end);
-
- if (ph)
- {
- assert (ph->end < h->start);
- assert (h->start <= (POINTER)h && (POINTER)(h+1) <= h->bloc_start);
- }
-
- if (h->bloc_start <= break_value && break_value <= h->end)
- found = 1;
-
- ph = h;
- }
-
- assert(found);
- assert(last_heap == ph);
-
- for (b = first_bloc; b; b = b->next)
- {
- assert(b->prev == pb);
- assert((POINTER) MEM_ROUNDUP(b->data) == b->data);
- assert((SIZE) MEM_ROUNDUP(b->size) == b->size);
-
- ph = 0;
- for (h = first_heap; h; h = h->next)
- {
- if (h->bloc_start <= b->data && b->data + b->size <= h->end)
- break;
- ph = h;
- }
-
- assert(h);
-
- if (pb && pb->data + pb->size != b->data)
- {
- assert(ph && b->data == h->bloc_start);
- while (ph)
- {
- if (ph->bloc_start <= pb->data
- && pb->data + pb->size <= ph->end)
- {
- assert(pb->data + pb->size + b->size > ph->end);
- break;
- }
- else
- {
- assert(ph->bloc_start + b->size > ph->end);
- }
- ph = ph->prev;
- }
- }
- pb = b;
- }
-
- assert(last_bloc == pb);
-
- if (last_bloc)
- assert(last_bloc->data + last_bloc->size == break_value);
- else
- assert(first_heap->bloc_start == break_value);
-}
-#endif /* DEBUG */
HCoop / bpt / emacs.git / blobdiff