libffi/src/arm/ffi.c

   1 /* -----------------------------------------------------------------------
   2    ffi.c - Copyright (c) 1998  Red Hat, Inc.
   3
   4    ARM Foreign Function Interface
   5
   6    Permission is hereby granted, free of charge, to any person obtaining
   7    a copy of this software and associated documentation files (the
   8    ``Software''), to deal in the Software without restriction, including
   9    without limitation the rights to use, copy, modify, merge, publish,
  10    distribute, sublicense, and/or sell copies of the Software, and to
  11    permit persons to whom the Software is furnished to do so, subject to
  12    the following conditions:
  13
  14    The above copyright notice and this permission notice shall be included
  15    in all copies or substantial portions of the Software.
  16
  17    THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  19    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  20    IN NO EVENT SHALL CYGNUS SOLUTIONS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  21    OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  22    ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  23    OTHER DEALINGS IN THE SOFTWARE.
  24    ----------------------------------------------------------------------- */
  25
  26 #include <ffi.h>
  27 #include <ffi_common.h>
  28
  29 #include <stdlib.h>
  30
  31 /* ffi_prep_args is called by the assembly routine once stack space
  32    has been allocated for the function's arguments */
  33
  34 void ffi_prep_args(char *stack, extended_cif *ecif)
  35 {
  36   register unsigned int i;
  37   register void **p_argv;
  38   register char *argp;
  39   register ffi_type **p_arg;
  40
  41   argp = stack;
  42
  43   if ( ecif->cif->rtype->type == FFI_TYPE_STRUCT ) {
  44     *(void **) argp = ecif->rvalue;
  45     argp += 4;
  46   }
  47
  48   p_argv = ecif->avalue;
  49
  50   for (i = ecif->cif->nargs, p_arg = ecif->cif->arg_types;
  51        (i != 0);
  52        i--, p_arg++)
  53     {
  54       size_t z;
  55
  56       /* Align if necessary */
  57       if (((*p_arg)->alignment - 1) & (unsigned) argp) {
  58         argp = (char *) ALIGN(argp, (*p_arg)->alignment);
  59       }
  60
  61           z = (*p_arg)->size;
  62           if (z < sizeof(int))
  63             {
  64               z = sizeof(int);
  65               switch ((*p_arg)->type)
  66                 {
  67                 case FFI_TYPE_SINT8:
  68                   *(signed int *) argp = (signed int)*(SINT8 *)(* p_argv);
  69                   break;
  70
  71                 case FFI_TYPE_UINT8:
  72                   *(unsigned int *) argp = (unsigned int)*(UINT8 *)(* p_argv);
  73                   break;
  74
  75                 case FFI_TYPE_SINT16:
  76                   *(signed int *) argp = (signed int)*(SINT16 *)(* p_argv);
  77                   break;
  78
  79                 case FFI_TYPE_UINT16:
  80                   *(unsigned int *) argp = (unsigned int)*(UINT16 *)(* p_argv);
  81                   break;
  82
  83                 case FFI_TYPE_STRUCT:
  84                   *(unsigned int *) argp = (unsigned int)*(UINT32 *)(* p_argv);
  85                   break;
  86
  87                 default:
  88                   FFI_ASSERT(0);
  89                 }
  90             }
  91           else if (z == sizeof(int))
  92             {
  93               *(unsigned int *) argp = (unsigned int)*(UINT32 *)(* p_argv);
  94             }
  95           else
  96             {
  97               memcpy(argp, *p_argv, z);
  98             }
  99           p_argv++;
 100           argp += z;
 101     }
 102
 103   return;
 104 }
 105
 106 /* Perform machine dependent cif processing */
 107 ffi_status ffi_prep_cif_machdep(ffi_cif *cif)
 108 {
 109   /* Round the stack up to a multiple of 8 bytes.  This isn't needed
 110      everywhere, but it is on some platforms, and it doesn't harm anything
 111      when it isn't needed.  */
 112   cif->bytes = (cif->bytes + 7) & ~7;
 113
 114   /* Set the return type flag */
 115   switch (cif->rtype->type)
 116     {
 117     case FFI_TYPE_VOID:
 118     case FFI_TYPE_STRUCT:
 119     case FFI_TYPE_FLOAT:
 120     case FFI_TYPE_DOUBLE:
 121       cif->flags = (unsigned) cif->rtype->type;
 122       break;
 123
 124     case FFI_TYPE_SINT64:
 125     case FFI_TYPE_UINT64:
 126       cif->flags = (unsigned) FFI_TYPE_SINT64;
 127       break;
 128
 129     default:
 130       cif->flags = FFI_TYPE_INT;
 131       break;
 132     }
 133
 134   return FFI_OK;
 135 }
 136
 137 extern void ffi_call_SYSV(void (*)(char *, extended_cif *), extended_cif *,
 138                           unsigned, unsigned, unsigned *, void (*fn)());
 139
 140 void ffi_call(ffi_cif *cif, void (*fn)(), void *rvalue, void **avalue)
 141 {
 142   extended_cif ecif;
 143
 144   ecif.cif = cif;
 145   ecif.avalue = avalue;
 146
 147   /* If the return value is a struct and we don't have a return */
 148   /* value address then we need to make one                     */
 149
 150   if ((rvalue == NULL) &&
 151       (cif->rtype->type == FFI_TYPE_STRUCT))
 152     {
 153       ecif.rvalue = alloca(cif->rtype->size);
 154     }
 155   else
 156     ecif.rvalue = rvalue;
 157
 158
 159   switch (cif->abi)
 160     {
 161     case FFI_SYSV:
 162       ffi_call_SYSV(ffi_prep_args, &ecif, cif->bytes, cif->flags, ecif.rvalue,
 163                     fn);
 164
 165       break;
 166     default:
 167       FFI_ASSERT(0);
 168       break;
 169     }
 170 }