old-autovect-branch/libffi/src/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 #ifndef __CRIS__
  85 /* The CRIS ABI specifies structure elements to have byte
  86    alignment only, so it completely overrides this functions,
  87    which assumes "natural" alignment and padding.  */
  88
  89 /* Perform machine independent ffi_cif preparation, then call
  90    machine dependent routine. */
  91
  92 ffi_status ffi_prep_cif(/*@out@*/ /*@partial@*/ ffi_cif *cif,
  93                         ffi_abi abi, unsigned int nargs,
  94                         /*@dependent@*/ /*@out@*/ /*@partial@*/ ffi_type *rtype,
  95                         /*@dependent@*/ ffi_type **atypes)
  96 {
  97   unsigned bytes = 0;
  98   unsigned int i;
  99   ffi_type **ptr;
 100
 101   FFI_ASSERT(cif != NULL);
 102   FFI_ASSERT((abi > FFI_FIRST_ABI) && (abi <= FFI_DEFAULT_ABI));
 103
 104   cif->abi = abi;
 105   cif->arg_types = atypes;
 106   cif->nargs = nargs;
 107   cif->rtype = rtype;
 108
 109   cif->flags = 0;
 110
 111   /* Initialize the return type if necessary */
 112   /*@-usedef@*/
 113   if ((cif->rtype->size == 0) && (initialize_aggregate(cif->rtype) != FFI_OK))
 114     return FFI_BAD_TYPEDEF;
 115   /*@=usedef@*/
 116
 117   /* Perform a sanity check on the return type */
 118   FFI_ASSERT_VALID_TYPE(cif->rtype);
 119
 120   /* x86-64 and s390 stack space allocation is handled in prep_machdep.  */
 121 #if !defined M68K && !defined __x86_64__ && !defined S390 && !defined PA
 122   /* Make space for the return structure pointer */
 123   if (cif->rtype->type == FFI_TYPE_STRUCT
 124 #ifdef SPARC
 125       && (cif->abi != FFI_V9 || cif->rtype->size > 32)
 126 #endif
 127       )
 128     bytes = STACK_ARG_SIZE(sizeof(void*));
 129 #endif
 130
 131   for (ptr = cif->arg_types, i = cif->nargs; i > 0; i--, ptr++)
 132     {
 133
 134       /* Initialize any uninitialized aggregate type definitions */
 135       if (((*ptr)->size == 0) && (initialize_aggregate((*ptr)) != FFI_OK))
 136         return FFI_BAD_TYPEDEF;
 137
 138       /* Perform a sanity check on the argument type, do this
 139          check after the initialization.  */
 140       FFI_ASSERT_VALID_TYPE(*ptr);
 141
 142 #if !defined __x86_64__ && !defined S390 && !defined PA
 143 #ifdef SPARC
 144       if (((*ptr)->type == FFI_TYPE_STRUCT
 145            && ((*ptr)->size > 16 || cif->abi != FFI_V9))
 146           || ((*ptr)->type == FFI_TYPE_LONGDOUBLE
 147               && cif->abi != FFI_V9))
 148         bytes += sizeof(void*);
 149       else
 150 #endif
 151         {
 152           /* Add any padding if necessary */
 153           if (((*ptr)->alignment - 1) & bytes)
 154             bytes = ALIGN(bytes, (*ptr)->alignment);
 155
 156           bytes += STACK_ARG_SIZE((*ptr)->size);
 157         }
 158 #endif
 159     }
 160
 161   cif->bytes = bytes;
 162
 163   /* Perform machine dependent cif processing */
 164   return ffi_prep_cif_machdep(cif);
 165 }
 166 #endif /* not __CRIS__ */