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 }