gcc/config/i386/gmm_malloc.h

   1 /* Copyright (C) 2004-2017 Free Software Foundation, Inc.
   2
   3    This file is part of GCC.
   4
   5    GCC is free software; you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation; either version 3, or (at your option)
   8    any later version.
   9
  10    GCC is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    Under Section 7 of GPL version 3, you are granted additional
  16    permissions described in the GCC Runtime Library Exception, version
  17    3.1, as published by the Free Software Foundation.
  18
  19    You should have received a copy of the GNU General Public License and
  20    a copy of the GCC Runtime Library Exception along with this program;
  21    see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  22    <http://www.gnu.org/licenses/>.  */
  23
  24 #ifndef _MM_MALLOC_H_INCLUDED
  25 #define _MM_MALLOC_H_INCLUDED
  26
  27 #include <stdlib.h>
  28 #include <errno.h>
  29
  30 static __inline__ void *
  31 _mm_malloc (size_t __size, size_t __align)
  32 {
  33   void * __malloc_ptr;
  34   void * __aligned_ptr;
  35
  36   /* Error if align is not a power of two.  */
  37   if (__align & (__align - 1))
  38     {
  39       errno = EINVAL;
  40       return ((void *) 0);
  41     }
  42
  43   if (__size == 0)
  44     return ((void *) 0);
  45
  46  /* Assume malloc'd pointer is aligned at least to sizeof (void*).
  47     If necessary, add another sizeof (void*) to store the value
  48     returned by malloc. Effectively this enforces a minimum alignment
  49     of sizeof double. */
  50     if (__align < 2 * sizeof (void *))
  51       __align = 2 * sizeof (void *);
  52
  53   __malloc_ptr = malloc (__size + __align);
  54   if (!__malloc_ptr)
  55     return ((void *) 0);
  56
  57   /* Align  We have at least sizeof (void *) space below malloc'd ptr. */
  58   __aligned_ptr = (void *) (((size_t) __malloc_ptr + __align)
  59                             & ~((size_t) (__align) - 1));
  60
  61   /* Store the original pointer just before p.  */
  62   ((void **) __aligned_ptr)[-1] = __malloc_ptr;
  63
  64   return __aligned_ptr;
  65 }
  66
  67 static __inline__ void
  68 _mm_free (void *__aligned_ptr)
  69 {
  70   if (__aligned_ptr)
  71     free (((void **) __aligned_ptr)[-1]);
  72 }
  73
  74 #endif /* _MM_MALLOC_H_INCLUDED */