Modules/_ctypes/libffi_arm_wince/prep_cif.c

   1 /* -----------------------------------------------------------------------
   2    prep_cif.c - Copyright (c) 1996, 1998  Red Hat, Inc.
   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 FFI_SIZEOF_ARG. */
  30
  31 #define STACK_ARG_SIZE(x) ALIGN(x, FFI_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_VALID_TYPE(*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   /* Structure size includes tail padding.  This is important for
  68      structures that fit in one register on ABIs like the PowerPC64
  69      Linux ABI that right justify small structs in a register.
  70      It's also needed for nested structure layout, for example
  71      struct A { long a; char b; }; struct B { struct A x; char y; };
  72      should find y at an offset of 2*sizeof(long) and result in a
  73      total size of 3*sizeof(long).  */
  74   arg->size = ALIGN (arg->size, arg->alignment);
  75
  76   if (arg->size == 0)
  77     return FFI_BAD_TYPEDEF;
  78   else
  79     return FFI_OK;
  80
  81   /*@=usedef@*/
  82 }
  83
  84 /* Perform machine independent ffi_cif preparation, then call
  85    machine dependent routine. */
  86
  87 ffi_status ffi_prep_cif(/*@out@*/ /*@partial@*/ ffi_cif *cif,
  88                         ffi_abi abi, unsigned int nargs,
  89                         /*@dependent@*/ /*@out@*/ /*@partial@*/ ffi_type *rtype,
  90                         /*@dependent@*/ ffi_type **atypes)
  91 {
  92   unsigned bytes = 0;
  93   unsigned int i;
  94   ffi_type **ptr;
  95
  96   FFI_ASSERT(cif != NULL);
  97   FFI_ASSERT((abi > FFI_FIRST_ABI) && (abi <= FFI_DEFAULT_ABI));
  98
  99   cif->abi = abi;
 100   cif->arg_types = atypes;
 101   cif->nargs = nargs;
 102   cif->rtype = rtype;
 103
 104   cif->flags = 0;
 105
 106   /* Initialize the return type if necessary */
 107   /*@-usedef@*/
 108   if ((cif->rtype->size == 0) && (initialize_aggregate(cif->rtype) != FFI_OK))
 109     return FFI_BAD_TYPEDEF;
 110   /*@=usedef@*/
 111
 112   /* Perform a sanity check on the return type */
 113   FFI_ASSERT_VALID_TYPE(cif->rtype);
 114
 115   /* x86-64 and s390 stack space allocation is handled in prep_machdep.  */
 116 #if !defined M68K && !defined __x86_64__ && !defined S390
 117   /* Make space for the return structure pointer */
 118   if (cif->rtype->type == FFI_TYPE_STRUCT
 119       /* MSVC returns small structures in registers.  But we have a different
 120       workaround: pretend int32 or int64 return type, and converting to
 121       structure afterwards. */
 122 #ifdef SPARC
 123       && (cif->abi != FFI_V9 || cif->rtype->size > 32)
 124 #endif
 125       )
 126     bytes = STACK_ARG_SIZE(sizeof(void*));
 127 #endif
 128
 129   for (ptr = cif->arg_types, i = cif->nargs; i > 0; i--, ptr++)
 130     {
 131
 132       /* Initialize any uninitialized aggregate type definitions */
 133       if (((*ptr)->size == 0) && (initialize_aggregate((*ptr)) != FFI_OK))
 134         return FFI_BAD_TYPEDEF;
 135
 136       /* Perform a sanity check on the argument type, do this
 137          check after the initialization.  */
 138       FFI_ASSERT_VALID_TYPE(*ptr);
 139
 140 #if !defined __x86_64__ && !defined S390
 141 #ifdef SPARC
 142       if (((*ptr)->type == FFI_TYPE_STRUCT
 143            && ((*ptr)->size > 16 || cif->abi != FFI_V9))
 144           || ((*ptr)->type == FFI_TYPE_LONGDOUBLE
 145               && cif->abi != FFI_V9))
 146         bytes += sizeof(void*);
 147       else
 148 #endif
 149         {
 150 #ifndef _MSC_VER
 151                 /* Don't know if this is a libffi bug or not.  At least on
 152                    Windows with MSVC, function call parameters are *not*
 153                    aligned in the same way as structure fields are, they are
 154                    only aligned in integer boundaries.
 155
 156                    This doesn't do any harm for cdecl functions and closures,
 157                    since the caller cleans up the stack, but it is wrong for
 158                    stdcall functions where the callee cleans.
 159                 */
 160
 161           /* Add any padding if necessary */
 162           if (((*ptr)->alignment - 1) & bytes)
 163             bytes = ALIGN(bytes, (*ptr)->alignment);
 164
 165 #endif
 166           bytes += STACK_ARG_SIZE((*ptr)->size);
 167         }
 168 #endif
 169     }
 170
 171   cif->bytes = bytes;
 172
 173   /* Perform machine dependent cif processing */
 174   return ffi_prep_cif_machdep(cif);
 175 }