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-rw-r--r--gcc-4.2.1-5666.3/libiberty/objalloc.c291
1 files changed, 291 insertions, 0 deletions
diff --git a/gcc-4.2.1-5666.3/libiberty/objalloc.c b/gcc-4.2.1-5666.3/libiberty/objalloc.c
new file mode 100644
index 000000000..3ddac2ce4
--- /dev/null
+++ b/gcc-4.2.1-5666.3/libiberty/objalloc.c
@@ -0,0 +1,291 @@
+/* objalloc.c -- routines to allocate memory for objects
+ Copyright 1997 Free Software Foundation, Inc.
+ Written by Ian Lance Taylor, Cygnus Solutions.
+
+This program is free software; you can redistribute it and/or modify it
+under the terms of the GNU General Public License as published by the
+Free Software Foundation; either version 2, or (at your option) any
+later version.
+
+This program 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 this program; if not, write to the Free Software
+Foundation, 51 Franklin Street - Fifth Floor,
+Boston, MA 02110-1301, USA. */
+
+#include "config.h"
+#include "ansidecl.h"
+
+#include "objalloc.h"
+
+/* Get a definition for NULL. */
+#include <stdio.h>
+
+#if VMS
+#include <stdlib.h>
+#include <unixlib.h>
+#else
+
+/* Get a definition for size_t. */
+#include <stddef.h>
+
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#else
+/* For systems with larger pointers than ints, this must be declared. */
+extern PTR malloc (size_t);
+extern void free (PTR);
+#endif
+
+#endif
+
+/* These routines allocate space for an object. Freeing allocated
+ space may or may not free all more recently allocated space.
+
+ We handle large and small allocation requests differently. If we
+ don't have enough space in the current block, and the allocation
+ request is for more than 512 bytes, we simply pass it through to
+ malloc. */
+
+/* The objalloc structure is defined in objalloc.h. */
+
+/* This structure appears at the start of each chunk. */
+
+struct objalloc_chunk
+{
+ /* Next chunk. */
+ struct objalloc_chunk *next;
+ /* If this chunk contains large objects, this is the value of
+ current_ptr when this chunk was allocated. If this chunk
+ contains small objects, this is NULL. */
+ char *current_ptr;
+};
+
+/* The aligned size of objalloc_chunk. */
+
+#define CHUNK_HEADER_SIZE \
+ ((sizeof (struct objalloc_chunk) + OBJALLOC_ALIGN - 1) \
+ &~ (OBJALLOC_ALIGN - 1))
+
+/* We ask for this much memory each time we create a chunk which is to
+ hold small objects. */
+
+#define CHUNK_SIZE (4096 - 32)
+
+/* A request for this amount or more is just passed through to malloc. */
+
+#define BIG_REQUEST (512)
+
+/* Create an objalloc structure. */
+
+struct objalloc *
+objalloc_create (void)
+{
+ struct objalloc *ret;
+ struct objalloc_chunk *chunk;
+
+ ret = (struct objalloc *) malloc (sizeof *ret);
+ if (ret == NULL)
+ return NULL;
+
+ ret->chunks = (PTR) malloc (CHUNK_SIZE);
+ if (ret->chunks == NULL)
+ {
+ free (ret);
+ return NULL;
+ }
+
+ chunk = (struct objalloc_chunk *) ret->chunks;
+ chunk->next = NULL;
+ chunk->current_ptr = NULL;
+
+ ret->current_ptr = (char *) chunk + CHUNK_HEADER_SIZE;
+ ret->current_space = CHUNK_SIZE - CHUNK_HEADER_SIZE;
+
+ return ret;
+}
+
+/* Allocate space from an objalloc structure. */
+
+PTR
+_objalloc_alloc (struct objalloc *o, unsigned long len)
+{
+ /* We avoid confusion from zero sized objects by always allocating
+ at least 1 byte. */
+ if (len == 0)
+ len = 1;
+
+ len = (len + OBJALLOC_ALIGN - 1) &~ (OBJALLOC_ALIGN - 1);
+
+ if (len <= o->current_space)
+ {
+ o->current_ptr += len;
+ o->current_space -= len;
+ return (PTR) (o->current_ptr - len);
+ }
+
+ if (len >= BIG_REQUEST)
+ {
+ char *ret;
+ struct objalloc_chunk *chunk;
+
+ ret = (char *) malloc (CHUNK_HEADER_SIZE + len);
+ if (ret == NULL)
+ return NULL;
+
+ chunk = (struct objalloc_chunk *) ret;
+ chunk->next = (struct objalloc_chunk *) o->chunks;
+ chunk->current_ptr = o->current_ptr;
+
+ o->chunks = (PTR) chunk;
+
+ return (PTR) (ret + CHUNK_HEADER_SIZE);
+ }
+ else
+ {
+ struct objalloc_chunk *chunk;
+
+ chunk = (struct objalloc_chunk *) malloc (CHUNK_SIZE);
+ if (chunk == NULL)
+ return NULL;
+ chunk->next = (struct objalloc_chunk *) o->chunks;
+ chunk->current_ptr = NULL;
+
+ o->current_ptr = (char *) chunk + CHUNK_HEADER_SIZE;
+ o->current_space = CHUNK_SIZE - CHUNK_HEADER_SIZE;
+
+ o->chunks = (PTR) chunk;
+
+ return objalloc_alloc (o, len);
+ }
+}
+
+/* Free an entire objalloc structure. */
+
+void
+objalloc_free (struct objalloc *o)
+{
+ struct objalloc_chunk *l;
+
+ l = (struct objalloc_chunk *) o->chunks;
+ while (l != NULL)
+ {
+ struct objalloc_chunk *next;
+
+ next = l->next;
+ free (l);
+ l = next;
+ }
+
+ free (o);
+}
+
+/* Free a block from an objalloc structure. This also frees all more
+ recently allocated blocks. */
+
+void
+objalloc_free_block (struct objalloc *o, PTR block)
+{
+ struct objalloc_chunk *p, *small;
+ char *b = (char *) block;
+
+ /* First set P to the chunk which contains the block we are freeing,
+ and set Q to the last small object chunk we see before P. */
+ small = NULL;
+ for (p = (struct objalloc_chunk *) o->chunks; p != NULL; p = p->next)
+ {
+ if (p->current_ptr == NULL)
+ {
+ if (b > (char *) p && b < (char *) p + CHUNK_SIZE)
+ break;
+ small = p;
+ }
+ else
+ {
+ if (b == (char *) p + CHUNK_HEADER_SIZE)
+ break;
+ }
+ }
+
+ /* If we can't find the chunk, the caller has made a mistake. */
+ if (p == NULL)
+ abort ();
+
+ if (p->current_ptr == NULL)
+ {
+ struct objalloc_chunk *q;
+ struct objalloc_chunk *first;
+
+ /* The block is in a chunk containing small objects. We can
+ free every chunk through SMALL, because they have certainly
+ been allocated more recently. After SMALL, we will not see
+ any chunks containing small objects; we can free any big
+ chunk if the current_ptr is greater than or equal to B. We
+ can then reset the new current_ptr to B. */
+
+ first = NULL;
+ q = (struct objalloc_chunk *) o->chunks;
+ while (q != p)
+ {
+ struct objalloc_chunk *next;
+
+ next = q->next;
+ if (small != NULL)
+ {
+ if (small == q)
+ small = NULL;
+ free (q);
+ }
+ else if (q->current_ptr > b)
+ free (q);
+ else if (first == NULL)
+ first = q;
+
+ q = next;
+ }
+
+ if (first == NULL)
+ first = p;
+ o->chunks = (PTR) first;
+
+ /* Now start allocating from this small block again. */
+ o->current_ptr = b;
+ o->current_space = ((char *) p + CHUNK_SIZE) - b;
+ }
+ else
+ {
+ struct objalloc_chunk *q;
+ char *current_ptr;
+
+ /* This block is in a large chunk by itself. We can free
+ everything on the list up to and including this block. We
+ then start allocating from the next chunk containing small
+ objects, setting current_ptr from the value stored with the
+ large chunk we are freeing. */
+
+ current_ptr = p->current_ptr;
+ p = p->next;
+
+ q = (struct objalloc_chunk *) o->chunks;
+ while (q != p)
+ {
+ struct objalloc_chunk *next;
+
+ next = q->next;
+ free (q);
+ q = next;
+ }
+
+ o->chunks = (PTR) p;
+
+ while (p->current_ptr != NULL)
+ p = p->next;
+
+ o->current_ptr = current_ptr;
+ o->current_space = ((char *) p + CHUNK_SIZE) - current_ptr;
+ }
+}
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