summaryrefslogtreecommitdiff
path: root/src/cris/ffi.c
blob: e9c39530c22137a0add323527d3085fb4ae69e9c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
/* -----------------------------------------------------------------------
   ffi.c - Copyright (c) 1998 Cygnus Solutions
           Copyright (c) 2004 Simon Posnjak
	   Copyright (c) 2005 Axis Communications AB
	   Copyright (C) 2007 Free Software Foundation, Inc.

   CRIS Foreign Function Interface

   Permission is hereby granted, free of charge, to any person obtaining
   a copy of this software and associated documentation files (the
   ``Software''), to deal in the Software without restriction, including
   without limitation the rights to use, copy, modify, merge, publish,
   distribute, sublicense, and/or sell copies of the Software, and to
   permit persons to whom the Software is furnished to do so, subject to
   the following conditions:

   The above copyright notice and this permission notice shall be included
   in all copies or substantial portions of the Software.

   THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS
   OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
   IN NO EVENT SHALL SIMON POSNJAK BE LIABLE FOR ANY CLAIM, DAMAGES OR
   OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
   ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
   OTHER DEALINGS IN THE SOFTWARE.
   ----------------------------------------------------------------------- */

#include <ffi.h>
#include <ffi_common.h>

#define STACK_ARG_SIZE(x) ALIGN(x, FFI_SIZEOF_ARG)

static ffi_status
initialize_aggregate_packed_struct (ffi_type * arg)
{
  ffi_type **ptr;

  FFI_ASSERT (arg != NULL);

  FFI_ASSERT (arg->elements != NULL);
  FFI_ASSERT (arg->size == 0);
  FFI_ASSERT (arg->alignment == 0);

  ptr = &(arg->elements[0]);

  while ((*ptr) != NULL)
    {
      if (((*ptr)->size == 0)
	  && (initialize_aggregate_packed_struct ((*ptr)) != FFI_OK))
	return FFI_BAD_TYPEDEF;

      FFI_ASSERT (ffi_type_test ((*ptr)));

      arg->size += (*ptr)->size;

      arg->alignment = (arg->alignment > (*ptr)->alignment) ?
	arg->alignment : (*ptr)->alignment;

      ptr++;
    }

  if (arg->size == 0)
    return FFI_BAD_TYPEDEF;
  else
    return FFI_OK;
}

int
ffi_prep_args (char *stack, extended_cif * ecif)
{
  unsigned int i;
  unsigned int struct_count = 0;
  void **p_argv;
  char *argp;
  ffi_type **p_arg;

  argp = stack;

  p_argv = ecif->avalue;

  for (i = ecif->cif->nargs, p_arg = ecif->cif->arg_types;
       (i != 0); i--, p_arg++)
    {
      size_t z;

      switch ((*p_arg)->type)
	{
	case FFI_TYPE_STRUCT:
	  {
	    z = (*p_arg)->size;
	    if (z <= 4)
	      {
		memcpy (argp, *p_argv, z);
		z = 4;
	      }
	    else if (z <= 8)
	      {
		memcpy (argp, *p_argv, z);
		z = 8;
	      }
	    else
	      {
		unsigned int uiLocOnStack;
		z = sizeof (void *);
		uiLocOnStack = 4 * ecif->cif->nargs + struct_count;
		struct_count = struct_count + (*p_arg)->size;
		*(unsigned int *) argp =
		  (unsigned int) (UINT32 *) (stack + uiLocOnStack);
		memcpy ((stack + uiLocOnStack), *p_argv, (*p_arg)->size);
	      }
	    break;
	  }
	default:
	  z = (*p_arg)->size;
	  if (z < sizeof (int))
	    {
	      switch ((*p_arg)->type)
		{
		case FFI_TYPE_SINT8:
		  *(signed int *) argp = (signed int) *(SINT8 *) (*p_argv);
		  break;

		case FFI_TYPE_UINT8:
		  *(unsigned int *) argp =
		    (unsigned int) *(UINT8 *) (*p_argv);
		  break;

		case FFI_TYPE_SINT16:
		  *(signed int *) argp = (signed int) *(SINT16 *) (*p_argv);
		  break;

		case FFI_TYPE_UINT16:
		  *(unsigned int *) argp =
		    (unsigned int) *(UINT16 *) (*p_argv);
		  break;

		default:
		  FFI_ASSERT (0);
		}
	      z = sizeof (int);
	    }
	  else if (z == sizeof (int))
	    *(unsigned int *) argp = (unsigned int) *(UINT32 *) (*p_argv);
	  else
	    memcpy (argp, *p_argv, z);
	  break;
	}
      p_argv++;
      argp += z;
    }

  return (struct_count);
}

ffi_status
ffi_prep_cif (ffi_cif * cif,
	      ffi_abi abi, unsigned int nargs,
	      ffi_type * rtype, ffi_type ** atypes)
{
  unsigned bytes = 0;
  unsigned int i;
  ffi_type **ptr;

  FFI_ASSERT (cif != NULL);
  FFI_ASSERT ((abi > FFI_FIRST_ABI) && (abi <= FFI_DEFAULT_ABI));

  cif->abi = abi;
  cif->arg_types = atypes;
  cif->nargs = nargs;
  cif->rtype = rtype;

  cif->flags = 0;

  if ((cif->rtype->size == 0)
      && (initialize_aggregate_packed_struct (cif->rtype) != FFI_OK))
    return FFI_BAD_TYPEDEF;

  FFI_ASSERT_VALID_TYPE (cif->rtype);

  for (ptr = cif->arg_types, i = cif->nargs; i > 0; i--, ptr++)
    {
      if (((*ptr)->size == 0)
	  && (initialize_aggregate_packed_struct ((*ptr)) != FFI_OK))
	return FFI_BAD_TYPEDEF;

      FFI_ASSERT_VALID_TYPE (*ptr);

      if (((*ptr)->alignment - 1) & bytes)
	bytes = ALIGN (bytes, (*ptr)->alignment);
      if ((*ptr)->type == FFI_TYPE_STRUCT)
	{
	  if ((*ptr)->size > 8)
	    {
	      bytes += (*ptr)->size;
	      bytes += sizeof (void *);
	    }
	  else
	    {
	      if ((*ptr)->size > 4)
		bytes += 8;
	      else
		bytes += 4;
	    }
	}
      else
	bytes += STACK_ARG_SIZE ((*ptr)->size);
    }

  cif->bytes = bytes;

  return ffi_prep_cif_machdep (cif);
}

ffi_status
ffi_prep_cif_machdep (ffi_cif * cif)
{
  switch (cif->rtype->type)
    {
    case FFI_TYPE_VOID:
    case FFI_TYPE_STRUCT:
    case FFI_TYPE_FLOAT:
    case FFI_TYPE_DOUBLE:
    case FFI_TYPE_SINT64:
    case FFI_TYPE_UINT64:
      cif->flags = (unsigned) cif->rtype->type;
      break;

    default:
      cif->flags = FFI_TYPE_INT;
      break;
    }

  return FFI_OK;
}

extern void ffi_call_SYSV (int (*)(char *, extended_cif *),
			   extended_cif *,
			   unsigned, unsigned, unsigned *, void (*fn) ())
     __attribute__ ((__visibility__ ("hidden")));

void
ffi_call (ffi_cif * cif, void (*fn) (), void *rvalue, void **avalue)
{
  extended_cif ecif;

  ecif.cif = cif;
  ecif.avalue = avalue;

  if ((rvalue == NULL) && (cif->rtype->type == FFI_TYPE_STRUCT))
    {
      ecif.rvalue = alloca (cif->rtype->size);
    }
  else
    ecif.rvalue = rvalue;

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

/* Because the following variables are not exported outside libffi, we
   mark them hidden.  */

/* Assembly code for the jump stub.  */
extern const char ffi_cris_trampoline_template[]
 __attribute__ ((__visibility__ ("hidden")));

/* Offset into ffi_cris_trampoline_template of where to put the
   ffi_prep_closure_inner function.  */
extern const int ffi_cris_trampoline_fn_offset
 __attribute__ ((__visibility__ ("hidden")));

/* Offset into ffi_cris_trampoline_template of where to put the
   closure data.  */
extern const int ffi_cris_trampoline_closure_offset
 __attribute__ ((__visibility__ ("hidden")));

/* This function is sibling-called (jumped to) by the closure
   trampoline.  We get R10..R13 at PARAMS[0..3] and a copy of [SP] at
   PARAMS[4] to simplify handling of a straddling parameter.  A copy
   of R9 is at PARAMS[5] and SP at PARAMS[6].  These parameters are
   put at the appropriate place in CLOSURE which is then executed and
   the return value is passed back to the caller.  */

static unsigned long long
ffi_prep_closure_inner (void **params, ffi_closure* closure)
{
  char *register_args = (char *) params;
  void *struct_ret = params[5];
  char *stack_args = params[6];
  char *ptr = register_args;
  ffi_cif *cif = closure->cif;
  ffi_type **arg_types = cif->arg_types;

  /* Max room needed is number of arguments as 64-bit values.  */
  void **avalue = alloca (closure->cif->nargs * sizeof(void *));
  int i;
  int doing_regs;
  long long llret = 0;

  /* Find the address of each argument.  */
  for (i = 0, doing_regs = 1; i < cif->nargs; i++)
    {
      /* Types up to and including 8 bytes go by-value.  */
      if (arg_types[i]->size <= 4)
	{
	  avalue[i] = ptr;
	  ptr += 4;
	}
      else if (arg_types[i]->size <= 8)
	{
	  avalue[i] = ptr;
	  ptr += 8;
	}
      else
	{
	  FFI_ASSERT (arg_types[i]->type == FFI_TYPE_STRUCT);

	  /* Passed by-reference, so copy the pointer.  */
	  avalue[i] = *(void **) ptr;
	  ptr += 4;
	}

      /* If we've handled more arguments than fit in registers, start
	 looking at the those passed on the stack.  Step over the
	 first one if we had a straddling parameter.  */
      if (doing_regs && ptr >= register_args + 4*4)
	{
	  ptr = stack_args + ((ptr > register_args + 4*4) ? 4 : 0);
	  doing_regs = 0;
	}
    }

  /* Invoke the closure.  */
  (closure->fun) (cif,

		  cif->rtype->type == FFI_TYPE_STRUCT
		  /* The caller allocated space for the return
		     structure, and passed a pointer to this space in
		     R9.  */
		  ? struct_ret

		  /* We take advantage of being able to ignore that
		     the high part isn't set if the return value is
		     not in R10:R11, but in R10 only.  */
		  : (void *) &llret,

		  avalue, closure->user_data);

  return llret;
}

/* API function: Prepare the trampoline.  */

ffi_status
ffi_prep_closure_loc (ffi_closure* closure,
		      ffi_cif* cif,
		      void (*fun)(ffi_cif *, void *, void **, void*),
		      void *user_data,
		      void *codeloc)
{
  void *innerfn = ffi_prep_closure_inner;
  FFI_ASSERT (cif->abi == FFI_SYSV);
  closure->cif  = cif;
  closure->user_data = user_data;
  closure->fun  = fun;
  memcpy (closure->tramp, ffi_cris_trampoline_template,
	  FFI_CRIS_TRAMPOLINE_CODE_PART_SIZE);
  memcpy (closure->tramp + ffi_cris_trampoline_fn_offset,
	  &innerfn, sizeof (void *));
  memcpy (closure->tramp + ffi_cris_trampoline_closure_offset,
	  &codeloc, sizeof (void *));

  return FFI_OK;
}