libffi/src/prep_cif.c

   1 /* -----------------------------------------------------------------------
   2    prep_cif.c - Copyright (c) 1996, 1998  Cygnus Solutions
   3
   4    Permission is hereby granted, free of charge, to any person obtaining
   5    a copy of this software and associated documentation files (the
   6    ``Software''), to deal in the Software without restriction, including
   7    without limitation the rights to use, copy, modify, merge, publish,
   8    distribute, sublicense, and/or sell copies of the Software, and to
   9    permit persons to whom the Software is furnished to do so, subject to
  10    the following conditions:
  11
  12    The above copyright notice and this permission notice shall be included
  13    in all copies or substantial portions of the Software.
  14
  15    THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS
  16    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  17    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  18    IN NO EVENT SHALL CYGNUS SOLUTIONS BE LIABLE FOR ANY CLAIM, DAMAGES OR
  19    OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
  20    ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
  21    OTHER DEALINGS IN THE SOFTWARE.
  22    ----------------------------------------------------------------------- */
  23
  24 #include <ffi.h>
  25 #include <ffi_common.h>
  26 #include <stdlib.h>
  27
  28
  29 /* Round up to SIZEOF_ARG. */
  30
  31 #define STACK_ARG_SIZE(x) ALIGN(x, SIZEOF_ARG)
  32
  33 /* Perform machine independent initialization of aggregate type
  34    specifications. */
  35
  36 static ffi_status initialize_aggregate(/*@out@*/ ffi_type *arg)
  37 {
  38   ffi_type **ptr;
  39
  40   FFI_ASSERT(arg != NULL);
  41
  42   /*@-usedef@*/
  43
  44   FFI_ASSERT(arg->elements != NULL);
  45   FFI_ASSERT(arg->size == 0);
  46   FFI_ASSERT(arg->alignment == 0);
  47
  48   ptr = &(arg->elements[0]);
  49
  50   while ((*ptr) != NULL)
  51     {
  52       if (((*ptr)->size == 0) && (initialize_aggregate((*ptr)) != FFI_OK))
  53         return FFI_BAD_TYPEDEF;
  54
  55       /* Perform a sanity check on the argument type */
  56       FFI_ASSERT(ffi_type_test((*ptr)));
  57
  58       arg->size = ALIGN(arg->size, (*ptr)->alignment);
  59       arg->size += (*ptr)->size;
  60
  61       arg->alignment = (arg->alignment > (*ptr)->alignment) ?
  62         arg->alignment : (*ptr)->alignment;
  63
  64       ptr++;
  65     }
  66
  67   if (arg->size == 0)
  68     return FFI_BAD_TYPEDEF;
  69   else
  70     return FFI_OK;
  71
  72   /*@=usedef@*/
  73 }
  74
  75 /* Perform machine independent ffi_cif preparation, then call
  76    machine dependent routine. */
  77
  78 ffi_status ffi_prep_cif(/*@out@*/ /*@partial@*/ ffi_cif *cif,
  79                         ffi_abi abi, unsigned int nargs,
  80                         /*@dependent@*/ /*@out@*/ /*@partial@*/ ffi_type *rtype,
  81                         /*@dependent@*/ ffi_type **atypes)
  82 {
  83   unsigned bytes = 0;
  84   unsigned int i;
  85   ffi_type **ptr;
  86
  87   FFI_ASSERT(cif != NULL);
  88   FFI_ASSERT((abi > FFI_FIRST_ABI) && (abi < FFI_LAST_ABI));
  89
  90   cif->abi = abi;
  91   cif->arg_types = atypes;
  92   cif->nargs = nargs;
  93   cif->rtype = rtype;
  94
  95   cif->flags = 0;
  96
  97   /* Initialize the return type if necessary */
  98   /*@-usedef@*/
  99   if ((cif->rtype->size == 0) && (initialize_aggregate(cif->rtype) != FFI_OK))
 100     return FFI_BAD_TYPEDEF;
 101   /*@=usedef@*/
 102
 103   /* Perform a sanity check on the return type */
 104   FFI_ASSERT(ffi_type_test(cif->rtype));
 105
 106   /* x86-64 and s390 stack space allocation is handled in prep_machdep.  */
 107 #if !defined M68K && !defined __x86_64__ && !defined S390
 108   /* Make space for the return structure pointer */
 109   if (cif->rtype->type == FFI_TYPE_STRUCT
 110 #ifdef SPARC
 111       && (cif->abi != FFI_V9 || cif->rtype->size > 32)
 112 #endif
 113       )
 114     bytes = STACK_ARG_SIZE(sizeof(void*));
 115 #endif
 116
 117   for (ptr = cif->arg_types, i = cif->nargs; i > 0; i--, ptr++)
 118     {
 119       /* Perform a sanity check on the argument type */
 120       FFI_ASSERT(ffi_type_test(*ptr));
 121
 122       /* Initialize any uninitialized aggregate type definitions */
 123       if (((*ptr)->size == 0) && (initialize_aggregate((*ptr)) != FFI_OK))
 124         return FFI_BAD_TYPEDEF;
 125
 126 #if !defined __x86_64__ && !defined S390
 127 #ifdef SPARC
 128       if (((*ptr)->type == FFI_TYPE_STRUCT
 129            && ((*ptr)->size > 16 || cif->abi != FFI_V9))
 130           || ((*ptr)->type == FFI_TYPE_LONGDOUBLE
 131               && cif->abi != FFI_V9))
 132         bytes += sizeof(void*);
 133       else
 134 #endif
 135         {
 136           /* Add any padding if necessary */
 137           if (((*ptr)->alignment - 1) & bytes)
 138             bytes = ALIGN(bytes, (*ptr)->alignment);
 139
 140           bytes += STACK_ARG_SIZE((*ptr)->size);
 141         }
 142 #endif
 143     }
 144
 145   cif->bytes = bytes;
 146
 147   /* Perform machine dependent cif processing */
 148   return ffi_prep_cif_machdep(cif);
 149 }