gcc/d/dmd/root/rmem.c

   1
   2 /* Copyright (C) 2000-2018 by The D Language Foundation, All Rights Reserved
   3  * http://www.digitalmars.com
   4  * Distributed under the Boost Software License, Version 1.0.
   5  * (See accompanying file LICENSE or copy at http://www.boost.org/LICENSE_1_0.txt)
   6  * https://github.com/D-Programming-Language/dmd/blob/master/src/root/rmem.c
   7  */
   8
   9 #include "dsystem.h"
  10 #include "rmem.h"
  11
  12 /* This implementation of the storage allocator uses the standard C allocation package.
  13  */
  14
  15 Mem mem;
  16
  17 char *Mem::xstrdup(const char *s)
  18 {
  19     char *p;
  20
  21     if (s)
  22     {
  23 #ifdef IN_GCC
  24         p = ::xstrdup(s);
  25 #else
  26         p = strdup(s);
  27 #endif
  28         if (p)
  29             return p;
  30         error();
  31     }
  32     return NULL;
  33 }
  34
  35 void *Mem::xmalloc(size_t size)
  36 {   void *p;
  37
  38     if (!size)
  39         p = NULL;
  40     else
  41     {
  42 #ifdef IN_GCC
  43         p = ::xmalloc(size);
  44 #else
  45         p = malloc(size);
  46 #endif
  47         if (!p)
  48             error();
  49     }
  50     return p;
  51 }
  52
  53 void *Mem::xcalloc(size_t size, size_t n)
  54 {   void *p;
  55
  56     if (!size || !n)
  57         p = NULL;
  58     else
  59     {
  60 #ifdef IN_GCC
  61         p = ::xcalloc(size, n);
  62 #else
  63         p = calloc(size, n);
  64 #endif
  65         if (!p)
  66             error();
  67     }
  68     return p;
  69 }
  70
  71 void *Mem::xrealloc(void *p, size_t size)
  72 {
  73     if (!size)
  74     {   if (p)
  75         {
  76             free(p);
  77             p = NULL;
  78         }
  79     }
  80     else if (!p)
  81     {
  82 #ifdef IN_GCC
  83         p = ::xmalloc(size);
  84 #else
  85         p = malloc(size);
  86 #endif
  87         if (!p)
  88             error();
  89     }
  90     else
  91     {
  92         void *psave = p;
  93 #ifdef IN_GCC
  94         p = ::xrealloc(psave, size);
  95 #else
  96         p = realloc(psave, size);
  97 #endif
  98         if (!p)
  99         {   xfree(psave);
 100             error();
 101         }
 102     }
 103     return p;
 104 }
 105
 106 void Mem::xfree(void *p)
 107 {
 108     if (p)
 109         free(p);
 110 }
 111
 112 void *Mem::xmallocdup(void *o, size_t size)
 113 {   void *p;
 114
 115     if (!size)
 116         p = NULL;
 117     else
 118     {
 119 #ifdef IN_GCC
 120         p = ::xmalloc(size);
 121 #else
 122         p = malloc(size);
 123 #endif
 124         if (!p)
 125             error();
 126         else
 127             memcpy(p,o,size);
 128     }
 129     return p;
 130 }
 131
 132 void Mem::error()
 133 {
 134     printf("Error: out of memory\n");
 135     exit(EXIT_FAILURE);
 136 }
 137
 138 /* =================================================== */
 139
 140 /* Allocate, but never release
 141  */
 142
 143 // Allocate a little less than 1Mb because the C runtime adds some overhead that
 144 // causes the actual memory block to be larger than 1Mb otherwise.
 145 #define CHUNK_SIZE (256 * 4096 - 64)
 146
 147 static size_t heapleft = 0;
 148 static void *heapp;
 149
 150 extern "C" void *allocmemory(size_t m_size)
 151 {
 152     // 16 byte alignment is better (and sometimes needed) for doubles
 153     m_size = (m_size + 15) & ~15;
 154
 155     // The layout of the code is selected so the most common case is straight through
 156     if (m_size <= heapleft)
 157     {
 158      L1:
 159         heapleft -= m_size;
 160         void *p = heapp;
 161         heapp = (void *)((char *)heapp + m_size);
 162         return p;
 163     }
 164
 165     if (m_size > CHUNK_SIZE)
 166     {
 167 #ifdef IN_GCC
 168         void *p = xmalloc(m_size);
 169 #else
 170         void *p = malloc(m_size);
 171 #endif
 172         if (p)
 173             return p;
 174         printf("Error: out of memory\n");
 175         exit(EXIT_FAILURE);
 176         return p;
 177     }
 178
 179     heapleft = CHUNK_SIZE;
 180 #ifdef IN_GCC
 181     heapp = xmalloc(CHUNK_SIZE);
 182 #else
 183     heapp = malloc(CHUNK_SIZE);
 184 #endif
 185     if (!heapp)
 186     {
 187         printf("Error: out of memory\n");
 188         exit(EXIT_FAILURE);
 189     }
 190     goto L1;
 191 }