freebsd-src/contrib/gcc/varray.c
1999-08-26 09:30:50 +00:00

71 lines
2.1 KiB
C

/* Virtual array support.
Copyright (C) 1998 Free Software Foundation, Inc.
Contributed by Cygnus Solutions.
This file is part of GNU CC.
GNU CC is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
GNU CC 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 CC; see the file COPYING. If not, write to the Free
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include "config.h"
#include "system.h"
#include "rtl.h"
#include "tree.h"
#include "bitmap.h"
#include "varray.h"
#define VARRAY_HDR_SIZE (sizeof (struct varray_head_tag) - sizeof (varray_data))
/* Allocate a virtual array with NUM_ELEMENT elements, each of which is
ELEMENT_SIZE bytes long, named NAME. Array elements are zeroed. */
varray_type
varray_init (num_elements, element_size, name)
size_t num_elements;
size_t element_size;
const char *name;
{
size_t data_size = num_elements * element_size;
varray_type ptr = (varray_type) xcalloc (VARRAY_HDR_SIZE + data_size, 1);
ptr->num_elements = num_elements;
ptr->element_size = element_size;
ptr->name = name;
return ptr;
}
/* Grow/shrink the virtual array VA to N elements. Zero any new elements
allocated. */
varray_type
varray_grow (va, n)
varray_type va;
size_t n;
{
size_t old_elements = va->num_elements;
if (n != old_elements)
{
size_t element_size = va->element_size;
size_t old_data_size = old_elements * element_size;
size_t data_size = n * element_size;
va = (varray_type) xrealloc ((char *)va, VARRAY_HDR_SIZE + data_size);
va->num_elements = n;
if (n > old_elements)
bzero (&va->data.c[old_data_size], data_size - old_data_size);
}
return va;
}