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 
ffi_prep_args(char * stack,extended_cif * ecif)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 : ALIGN_DOWN(count, 8)));
111 }
112 
113 /* Perform machine dependent cif processing */
ffi_prep_cif_machdep(ffi_cif * cif)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 = 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 
ffi_call(ffi_cif * cif,void (* fn)(void),void * rvalue,void ** avalue)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 
ffi_closure_eabi(unsigned arg1,unsigned arg2,unsigned arg3,unsigned arg4,unsigned arg5,unsigned arg6)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
ffi_prep_closure_loc(ffi_closure * closure,ffi_cif * cif,void (* fun)(ffi_cif *,void *,void **,void *),void * user_data,void * codeloc)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 }
293