libffi/src/frv/ffi.c

   1 /* -----------------------------------------------------------------------
   2    ffi.c - Copyright (C) 2004  Anthony Green
   3    Copyright (C) 2007  Free Software Foundation, Inc.
   4            Copyright (C) 2008  Red Hat, Inc.
   5
   6    FR-V Foreign Function Interface
   7
   8    Permission is hereby granted, free of charge, to any person obtaining
   9    a copy of this software and associated documentation files (the
  10    ``Software''), to deal in the Software without restriction, including
  11    without limitation the rights to use, copy, modify, merge, publish,
  12    distribute, sublicense, and/or sell copies of the Software, and to
  13    permit persons to whom the Software is furnished to do so, subject to
  14    the following conditions:
  15
  16    The above copyright notice and this permission notice shall be included
  17    in all copies or substantial portions of the Software.
  18
  19    THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND,
  20    EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  21    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  22    NONINFRINGEMENT.  IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  23    HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
  24    WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  25    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  26    DEALINGS IN THE SOFTWARE.
  27    ----------------------------------------------------------------------- */
  28
  29 #include <ffi.h>
  30 #include <ffi_common.h>
  31
  32 #include <stdlib.h>
  33
  34 /* ffi_prep_args is called by the assembly routine once stack space
  35    has been allocated for the function's arguments */
  36
  37 void *ffi_prep_args(char *stack, extended_cif *ecif)
  38 {
  39   register unsigned int i;
  40   register void **p_argv;
  41   register char *argp;
  42   register ffi_type **p_arg;
  43   register int count = 0;
  44
  45   p_argv = ecif->avalue;
  46   argp = stack;
  47
  48   for (i = ecif->cif->nargs, p_arg = ecif->cif->arg_types;
  49        (i != 0);
  50        i--, p_arg++)
  51     {
  52       size_t z;
  53
  54       z = (*p_arg)->size;
  55
  56       if ((*p_arg)->type == FFI_TYPE_STRUCT)
  57         {
  58           z = sizeof(void*);
  59           *(void **) argp = *p_argv;
  60         }
  61       /*      if ((*p_arg)->type == FFI_TYPE_FLOAT)
  62         {
  63           if (count > 24)
  64             {
  65               // This is going on the stack.  Turn it into a double.
  66               *(double *) argp = (double) *(float*)(* p_argv);
  67               z = sizeof(double);
  68             }
  69           else
  70             *(void **) argp = *(void **)(* p_argv);
  71         }  */
  72       else if (z < sizeof(int))
  73         {
  74           z = sizeof(int);
  75           switch ((*p_arg)->type)
  76             {
  77             case FFI_TYPE_SINT8:
  78               *(signed int *) argp = (signed int)*(SINT8 *)(* p_argv);
  79               break;
  80
  81             case FFI_TYPE_UINT8:
  82               *(unsigned int *) argp = (unsigned int)*(UINT8 *)(* p_argv);
  83               break;
  84
  85             case FFI_TYPE_SINT16:
  86               *(signed int *) argp = (signed int)*(SINT16 *)(* p_argv);
  87               break;
  88
  89             case FFI_TYPE_UINT16:
  90               *(unsigned int *) argp = (unsigned int)*(UINT16 *)(* p_argv);
  91               break;
  92
  93             default:
  94               FFI_ASSERT(0);
  95             }
  96         }
  97       else if (z == sizeof(int))
  98         {
  99           *(unsigned int *) argp = (unsigned int)*(UINT32 *)(* p_argv);
 100         }
 101       else
 102         {
 103           memcpy(argp, *p_argv, z);
 104         }
 105       p_argv++;
 106       argp += z;
 107       count += z;
 108     }
 109
 110   return (stack + ((count > 24) ? 24 : FFI_ALIGN_DOWN(count, 8)));
 111 }
 112
 113 /* Perform machine dependent cif processing */
 114 ffi_status ffi_prep_cif_machdep(ffi_cif *cif)
 115 {
 116   if (cif->rtype->type == FFI_TYPE_STRUCT)
 117     cif->flags = -1;
 118   else
 119     cif->flags = cif->rtype->size;
 120
 121   cif->bytes = FFI_ALIGN (cif->bytes, 8);
 122
 123   return FFI_OK;
 124 }
 125
 126 extern void ffi_call_EABI(void *(*)(char *, extended_cif *),
 127                           extended_cif *,
 128                           unsigned, unsigned,
 129                           unsigned *,
 130                           void (*fn)(void));
 131
 132 void ffi_call(ffi_cif *cif,
 133               void (*fn)(void),
 134               void *rvalue,
 135               void **avalue)
 136 {
 137   extended_cif ecif;
 138
 139   ecif.cif = cif;
 140   ecif.avalue = avalue;
 141
 142   /* If the return value is a struct and we don't have a return */
 143   /* value address then we need to make one                     */
 144
 145   if ((rvalue == NULL) &&
 146       (cif->rtype->type == FFI_TYPE_STRUCT))
 147     {
 148       ecif.rvalue = alloca(cif->rtype->size);
 149     }
 150   else
 151     ecif.rvalue = rvalue;
 152
 153
 154   switch (cif->abi)
 155     {
 156     case FFI_EABI:
 157       ffi_call_EABI(ffi_prep_args, &ecif, cif->bytes,
 158                     cif->flags, ecif.rvalue, fn);
 159       break;
 160     default:
 161       FFI_ASSERT(0);
 162       break;
 163     }
 164 }
 165
 166 void ffi_closure_eabi (unsigned arg1, unsigned arg2, unsigned arg3,
 167                        unsigned arg4, unsigned arg5, unsigned arg6)
 168 {
 169   /* This function is called by a trampoline.  The trampoline stows a
 170      pointer to the ffi_closure object in gr7.  We must save this
 171      pointer in a place that will persist while we do our work.  */
 172   register ffi_closure *creg __asm__ ("gr7");
 173   ffi_closure *closure = creg;
 174
 175   /* Arguments that don't fit in registers are found on the stack
 176      at a fixed offset above the current frame pointer.  */
 177   register char *frame_pointer __asm__ ("fp");
 178   char *stack_args = frame_pointer + 16;
 179
 180   /* Lay the register arguments down in a continuous chunk of memory.  */
 181   unsigned register_args[6] =
 182     { arg1, arg2, arg3, arg4, arg5, arg6 };
 183
 184   ffi_cif *cif = closure->cif;
 185   ffi_type **arg_types = cif->arg_types;
 186   void **avalue = alloca (cif->nargs * sizeof(void *));
 187   char *ptr = (char *) register_args;
 188   int i;
 189
 190   /* Find the address of each argument.  */
 191   for (i = 0; i < cif->nargs; i++)
 192     {
 193       switch (arg_types[i]->type)
 194         {
 195         case FFI_TYPE_SINT8:
 196         case FFI_TYPE_UINT8:
 197           avalue[i] = ptr + 3;
 198           break;
 199         case FFI_TYPE_SINT16:
 200         case FFI_TYPE_UINT16:
 201           avalue[i] = ptr + 2;
 202           break;
 203         case FFI_TYPE_SINT32:
 204         case FFI_TYPE_UINT32:
 205         case FFI_TYPE_FLOAT:
 206           avalue[i] = ptr;
 207           break;
 208         case FFI_TYPE_STRUCT:
 209           avalue[i] = *(void**)ptr;
 210           break;
 211         default:
 212           /* This is an 8-byte value.  */
 213           avalue[i] = ptr;
 214           ptr += 4;
 215           break;
 216         }
 217       ptr += 4;
 218
 219       /* If we've handled more arguments than fit in registers,
 220          start looking at the those passed on the stack.  */
 221       if (ptr == ((char *)register_args + (6*4)))
 222         ptr = stack_args;
 223     }
 224
 225   /* Invoke the closure.  */
 226   if (cif->rtype->type == FFI_TYPE_STRUCT)
 227     {
 228       /* The caller allocates space for the return structure, and
 229        passes a pointer to this space in gr3.  Use this value directly
 230        as the return value.  */
 231       register void *return_struct_ptr __asm__("gr3");
 232       (closure->fun) (cif, return_struct_ptr, avalue, closure->user_data);
 233     }
 234   else
 235     {
 236       /* Allocate space for the return value and call the function.  */
 237       long long rvalue;
 238       (closure->fun) (cif, &rvalue, avalue, closure->user_data);
 239
 240       /* Functions return 4-byte or smaller results in gr8.  8-byte
 241          values also use gr9.  We fill the both, even for small return
 242          values, just to avoid a branch.  */
 243       asm ("ldi  @(%0, #0), gr8" : : "r" (&rvalue));
 244       asm ("ldi  @(%0, #0), gr9" : : "r" (&((int *) &rvalue)[1]));
 245     }
 246 }
 247
 248 ffi_status
 249 ffi_prep_closure_loc (ffi_closure* closure,
 250                       ffi_cif* cif,
 251                       void (*fun)(ffi_cif*, void*, void**, void*),
 252                       void *user_data,
 253                       void *codeloc)
 254 {
 255   unsigned int *tramp = (unsigned int *) &closure->tramp[0];
 256   unsigned long fn = (long) ffi_closure_eabi;
 257   unsigned long cls = (long) codeloc;
 258 #ifdef __FRV_FDPIC__
 259   register void *got __asm__("gr15");
 260 #endif
 261   int i;
 262
 263   fn = (unsigned long) ffi_closure_eabi;
 264
 265 #ifdef __FRV_FDPIC__
 266   tramp[0] = &((unsigned int *)codeloc)[2];
 267   tramp[1] = got;
 268   tramp[2] = 0x8cfc0000 + (fn  & 0xffff); /* setlos lo(fn), gr6    */
 269   tramp[3] = 0x8efc0000 + (cls & 0xffff); /* setlos lo(cls), gr7   */
 270   tramp[4] = 0x8cf80000 + (fn  >> 16);    /* sethi hi(fn), gr6     */
 271   tramp[5] = 0x8ef80000 + (cls >> 16);    /* sethi hi(cls), gr7    */
 272   tramp[6] = 0x9cc86000;                  /* ldi @(gr6, #0), gr14  */
 273   tramp[7] = 0x8030e000;                  /* jmpl @(gr14, gr0)     */
 274 #else
 275   tramp[0] = 0x8cfc0000 + (fn  & 0xffff); /* setlos lo(fn), gr6    */
 276   tramp[1] = 0x8efc0000 + (cls & 0xffff); /* setlos lo(cls), gr7   */
 277   tramp[2] = 0x8cf80000 + (fn  >> 16);    /* sethi hi(fn), gr6     */
 278   tramp[3] = 0x8ef80000 + (cls >> 16);    /* sethi hi(cls), gr7    */
 279   tramp[4] = 0x80300006;                  /* jmpl @(gr0, gr6)      */
 280 #endif
 281
 282   closure->cif = cif;
 283   closure->fun = fun;
 284   closure->user_data = user_data;
 285
 286   /* Cache flushing.  */
 287   for (i = 0; i < FFI_TRAMPOLINE_SIZE; i++)
 288     __asm__ volatile ("dcf @(%0,%1)\n\tici @(%2,%1)" :: "r" (tramp), "r" (i),
 289                       "r" (codeloc));
 290
 291   return FFI_OK;
 292 }