OpenCores
URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [gnu-old/] [gdb-6.8/] [gdb/] [vec.c] - Blame information for rev 840

Details | Compare with Previous | View Log

Line No. Rev Author Line
1 24 jeremybenn
/* Vector API for GDB.
2
   Copyright (C) 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.
3
   Contributed by Nathan Sidwell <nathan@codesourcery.com>
4
 
5
   This file is part of GDB.
6
 
7
   This program is free software; you can redistribute it and/or modify
8
   it under the terms of the GNU General Public License as published by
9
   the Free Software Foundation; either version 3 of the License, or
10
   (at your option) any later version.
11
 
12
   This program is distributed in the hope that it will be useful,
13
   but WITHOUT ANY WARRANTY; without even the implied warranty of
14
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15
   GNU General Public License for more details.
16
 
17
   You should have received a copy of the GNU General Public License
18
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
19
 
20
#include "defs.h"
21
#include "vec.h"
22
 
23
struct vec_prefix
24
{
25
  unsigned num;
26
  unsigned alloc;
27
  void *vec[1];
28
};
29
 
30
/* Calculate the new ALLOC value, making sure that abs(RESERVE) slots
31
   are free.  If RESERVE < 0 grow exactly, otherwise grow
32
   exponentially.  */
33
 
34
static inline unsigned
35
calculate_allocation (const struct vec_prefix *pfx, int reserve)
36
{
37
  unsigned alloc = 0;
38
  unsigned num = 0;
39
 
40
  if (pfx)
41
    {
42
      alloc = pfx->alloc;
43
      num = pfx->num;
44
    }
45
  else if (!reserve)
46
    /* If there's no prefix, and we've not requested anything, then we
47
       will create a NULL vector.  */
48
    return 0;
49
 
50
  /* We must have run out of room.  */
51
  gdb_assert (alloc - num < (unsigned)(reserve < 0 ? -reserve : reserve));
52
 
53
  if (reserve < 0)
54
    /* Exact size.  */
55
    alloc = num + -reserve;
56
  else
57
    {
58
      /* Exponential growth. */
59
      if (!alloc)
60
        alloc = 4;
61
      else if (alloc < 16)
62
        /* Double when small.  */
63
        alloc = alloc * 2;
64
      else
65
        /* Grow slower when large.  */
66
        alloc = (alloc * 3 / 2);
67
 
68
      /* If this is still too small, set it to the right size. */
69
      if (alloc < num + reserve)
70
        alloc = num + reserve;
71
    }
72
  return alloc;
73
}
74
 
75
/* Ensure there are at least abs(RESERVE) free slots in VEC.  If
76
   RESERVE < 0 grow exactly, else grow exponentially.  As a special
77
   case, if VEC is NULL, and RESERVE is 0, no vector will be created. */
78
 
79
void *
80
vec_p_reserve (void *vec, int reserve)
81
{
82
  return vec_o_reserve (vec, reserve,
83
                        offsetof (struct vec_prefix, vec), sizeof (void *));
84
}
85
 
86
/* As vec_p_reserve, but for object vectors.  The vector's trailing
87
   array is at VEC_OFFSET offset and consists of ELT_SIZE sized
88
   elements.  */
89
 
90
void *
91
vec_o_reserve (void *vec, int reserve, size_t vec_offset, size_t elt_size)
92
{
93
  struct vec_prefix *pfx = vec;
94
  unsigned alloc = calculate_allocation (pfx, reserve);
95
 
96
  if (!alloc)
97
    return NULL;
98
 
99
  vec = xrealloc (vec, vec_offset + alloc * elt_size);
100
  ((struct vec_prefix *)vec)->alloc = alloc;
101
  if (!pfx)
102
    ((struct vec_prefix *)vec)->num = 0;
103
 
104
  return vec;
105
}
106
 
107
#if 0
108
/* Example uses.  */
109
DEF_VEC_I (int);
110
typedef struct X
111
{
112
  int i;
113
} obj_t;
114
typedef obj_t *ptr_t;
115
 
116
DEF_VEC_P (ptr_t);
117
DEF_VEC_O (obj_t);
118
#endif

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.