ffi.c

linux下编程用 编译软件

	  for (m = 0; m < n; m++)
	    cif->flags += FFI_TYPE_INT << (2 * j++);
	  break;
	}
    }
#else
  for (i = j = 0; i < cif->nargs && j < 4; i++)
    {
      size = (cif->arg_types)[i]->size;
      n = (size + sizeof (int) - 1) / sizeof (int);
      if (greg >= NGREGARG)
	continue;
      else if (greg + n - 1 >= NGREGARG)
	n = NGREGARG - greg;
      greg += n;
      for (m = 0; m < n; m++)
        cif->flags += FFI_TYPE_INT << (2 * j++);
    }
#endif

  /* Set the return type flag */
  switch (cif->rtype->type)
    {
    case FFI_TYPE_STRUCT:
      cif->flags += (unsigned) (return_type (cif->rtype)) << 24;
      break;

    case FFI_TYPE_VOID:
    case FFI_TYPE_FLOAT:
    case FFI_TYPE_DOUBLE:
    case FFI_TYPE_SINT64:
    case FFI_TYPE_UINT64:
      cif->flags += (unsigned) cif->rtype->type << 24;
      break;

    default:
      cif->flags += FFI_TYPE_INT << 24;
      break;
    }

  return FFI_OK;
}

/*@-declundef@*/
/*@-exportheader@*/
extern void ffi_call_SYSV(void (*)(char *, extended_cif *), 
			  /*@out@*/ extended_cif *, 
			  unsigned, unsigned, 
			  /*@out@*/ unsigned *, 
			  void (*fn)());
/*@=declundef@*/
/*@=exportheader@*/

void ffi_call(/*@dependent@*/ ffi_cif *cif, 
	      void (*fn)(), 
	      /*@out@*/ void *rvalue, 
	      /*@dependent@*/ void **avalue)
{
  extended_cif ecif;
  UINT64 trvalue;

  ecif.cif = cif;
  ecif.avalue = avalue;
  
  /* If the return value is a struct and we don't have a return	*/
  /* value address then we need to make one		        */

  if (cif->rtype->type == FFI_TYPE_STRUCT
      && return_type (cif->rtype) != FFI_TYPE_STRUCT)
    ecif.rvalue = &trvalue;
  else if ((rvalue == NULL) && 
      (cif->rtype->type == FFI_TYPE_STRUCT))
    {
      /*@-sysunrecog@*/
      ecif.rvalue = alloca(cif->rtype->size);
      /*@=sysunrecog@*/
    }
  else
    ecif.rvalue = rvalue;

  switch (cif->abi) 
    {
    case FFI_SYSV:
      /*@-usedef@*/
      ffi_call_SYSV(ffi_prep_args, &ecif, cif->bytes, 
		    cif->flags, ecif.rvalue, fn);
      /*@=usedef@*/
      break;
    default:
      FFI_ASSERT(0);
      break;
    }

  if (rvalue
      && cif->rtype->type == FFI_TYPE_STRUCT
      && return_type (cif->rtype) != FFI_TYPE_STRUCT)
    memcpy (rvalue, &trvalue, cif->rtype->size);
}

extern void ffi_closure_SYSV (void);
#if defined(__SH4__)
extern void __ic_invalidate (void *line);
#endif

ffi_status
ffi_prep_closure (ffi_closure* closure,
		  ffi_cif* cif,
		  void (*fun)(ffi_cif*, void*, void**, void*),
		  void *user_data)
{
  unsigned int *tramp;
  unsigned short insn;

  FFI_ASSERT (cif->abi == FFI_GCC_SYSV);

  tramp = (unsigned int *) &closure->tramp[0];
  /* Set T bit if the function returns a struct pointed with R2.  */
  insn = (return_type (cif->rtype) == FFI_TYPE_STRUCT
	  ? 0x0018 /* sett */
	  : 0x0008 /* clrt */);

#ifdef __LITTLE_ENDIAN__
  tramp[0] = 0xd301d102;
  tramp[1] = 0x0000412b | (insn << 16);
#else
  tramp[0] = 0xd102d301;
  tramp[1] = 0x412b0000 | insn;
#endif
  *(void **) &tramp[2] = (void *)closure;          /* ctx */
  *(void **) &tramp[3] = (void *)ffi_closure_SYSV; /* funaddr */

  closure->cif = cif;
  closure->fun = fun;
  closure->user_data = user_data;

#if defined(__SH4__)
  /* Flush the icache.  */
  __ic_invalidate(&closure->tramp[0]);
#endif

  return FFI_OK;
}

/* Basically the trampoline invokes ffi_closure_SYSV, and on 
 * entry, r3 holds the address of the closure.
 * After storing the registers that could possibly contain
 * parameters to be passed into the stack frame and setting
 * up space for a return value, ffi_closure_SYSV invokes the 
 * following helper function to do most of the work.
 */

#ifdef __LITTLE_ENDIAN__
#define OFS_INT8	0
#define OFS_INT16	0
#else
#define OFS_INT8	3
#define OFS_INT16	2
#endif

int
ffi_closure_helper_SYSV (ffi_closure *closure, void *rvalue, 
			 unsigned long *pgr, unsigned long *pfr, 
			 unsigned long *pst)
{
  void **avalue;
  ffi_type **p_arg;
  int i, avn;
  int ireg, greg = 0;
#if defined(__SH4__)
  int freg = 0;
#endif
  ffi_cif *cif; 
  double temp; 

  cif = closure->cif;
  avalue = alloca(cif->nargs * sizeof(void *));

  /* Copy the caller's structure return value address so that the closure
     returns the data directly to the caller.  */
  if (cif->rtype->type == FFI_TYPE_STRUCT && STRUCT_VALUE_ADDRESS_WITH_ARG)
    {
      rvalue = *pgr++;
      ireg = 1;
    }
  else
    ireg = 0;

  cif = closure->cif;
  greg = ireg;
  avn = cif->nargs;

  /* Grab the addresses of the arguments from the stack frame.  */
  for (i = 0, p_arg = cif->arg_types; i < avn; i++, p_arg++)
    {
      size_t z;

      z = (*p_arg)->size;
      if (z < sizeof(int))
	{
	  if (greg++ >= NGREGARG)
	    continue;

	  z = sizeof(int);
	  switch ((*p_arg)->type)
	    {
	    case FFI_TYPE_SINT8:
	    case FFI_TYPE_UINT8:
	      avalue[i] = (((char *)pgr) + OFS_INT8);
	      break;
  
	    case FFI_TYPE_SINT16:
	    case FFI_TYPE_UINT16:
	      avalue[i] = (((char *)pgr) + OFS_INT16);
	      break;
  
	    case FFI_TYPE_STRUCT:
	      avalue[i] = pgr;
	      break;

	    default:
	      FFI_ASSERT(0);
	    }
	  pgr++;
	}
      else if (z == sizeof(int))
	{
#if defined(__SH4__)
	  if ((*p_arg)->type == FFI_TYPE_FLOAT)
	    {
	      if (freg++ >= NFREGARG)
		continue;
	      avalue[i] = pfr;
	      pfr++;
	    }
	  else
#endif
	    {
	      if (greg++ >= NGREGARG)
		continue;
	      avalue[i] = pgr;
	      pgr++;
	    }
	}
#if defined(__SH4__)
      else if ((*p_arg)->type == FFI_TYPE_DOUBLE)
	{
	  if (freg + 1 >= NFREGARG)
	    continue;
	  freg = (freg + 1) & ~1;
	  freg += 2;
	  avalue[i] = pfr;
	  pfr += 2;
	}
#endif
      else
	{
	  int n = (z + sizeof (int) - 1) / sizeof (int);
#if defined(__SH4__)
	  if (greg + n - 1 >= NGREGARG)
	    continue;
#else
	  if (greg >= NGREGARG)
	    continue;
#endif
	  greg += n;
	  avalue[i] = pgr;
	  pgr += n;
	}
    }

  greg = ireg;
#if defined(__SH4__)
  freg = 0;
#endif

  for (i = 0, p_arg = cif->arg_types; i < avn; i++, p_arg++)
    {
      size_t z;

      z = (*p_arg)->size;
      if (z < sizeof(int))
	{
	  if (greg++ < NGREGARG)
	    continue;

	  z = sizeof(int);
	  switch ((*p_arg)->type)
	    {
	    case FFI_TYPE_SINT8:
	    case FFI_TYPE_UINT8:
	      avalue[i] = (((char *)pst) + OFS_INT8);
	      break;
  
	    case FFI_TYPE_SINT16:
	    case FFI_TYPE_UINT16:
	      avalue[i] = (((char *)pst) + OFS_INT16);
	      break;
  
	    case FFI_TYPE_STRUCT:
	      avalue[i] = pst;
	      break;

	    default:
	      FFI_ASSERT(0);
	    }
	  pst++;
	}
      else if (z == sizeof(int))
	{
#if defined(__SH4__)
	  if ((*p_arg)->type == FFI_TYPE_FLOAT)
	    {
	      if (freg++ < NFREGARG)
		continue;
	    }
	  else
#endif
	    {
	      if (greg++ < NGREGARG)
		continue;
	    }
	  avalue[i] = pst;
	  pst++;
	}
#if defined(__SH4__)
      else if ((*p_arg)->type == FFI_TYPE_DOUBLE)
	{
	  if (freg + 1 < NFREGARG)
	    {
	      freg = (freg + 1) & ~1;
	      freg += 2;
	      continue;
	    }
	  avalue[i] = pst;
	  pst += 2;
	}
#endif
      else
	{
	  int n = (z + sizeof (int) - 1) / sizeof (int);
	  if (greg + n - 1 < NGREGARG)
	    {
	      greg += n;
	      continue;
	    }
#if (! defined(__SH4__))
	  else if (greg < NGREGARG)
	    {
	      greg += n;
	      pst += greg - NGREGARG;
	      continue;
	    }
#endif
	  avalue[i] = pst;
	  pst += n;
	}
    }

  (closure->fun) (cif, rvalue, avalue, closure->user_data);

  /* Tell ffi_closure_SYSV how to perform return type promotions.  */
  return return_type (cif->rtype);
}