1 /* -----------------------------------------------------------------------
2    ffi.c - Copyright (c) 2004  Renesas Technology
3            Copyright (c) 2008  Red Hat, Inc.
4 
5    M32R Foreign Function Interface
6 
7    Permission is hereby granted, free of charge, to any person obtaining
8    a copy of this software and associated documentation files (the
9    ``Software''), to deal in the Software without restriction, including
10    without limitation the rights to use, copy, modify, merge, publish,
11    distribute, sublicense, and/or sell copies of the Software, and to
12    permit persons to whom the Software is furnished to do so, subject to
13    the following conditions:
14 
15    The above copyright notice and this permission notice shall be included
16    in all copies or substantial portions of the Software.
17 
18    THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS
19    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
21    IN NO EVENT SHALL RENESAS TECHNOLOGY BE LIABLE FOR ANY CLAIM, DAMAGES OR
22    OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
23    ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
24    OTHER DEALINGS IN THE SOFTWARE.
25    ----------------------------------------------------------------------- */
26 
27 #include <ffi.h>
28 #include <ffi_common.h>
29 
30 #include <stdlib.h>
31 
32 /* ffi_prep_args is called by the assembly routine once stack
33    space has been allocated for the function's arguments.  */
34 
35 void ffi_prep_args(char *stack, extended_cif *ecif)
36 {
37   unsigned int i;
38   int tmp;
39   unsigned int avn;
40   void **p_argv;
41   char *argp;
42   ffi_type **p_arg;
43 
44   tmp = 0;
45   argp = stack;
46 
47   if (ecif->cif->rtype->type == FFI_TYPE_STRUCT && ecif->cif->rtype->size > 8)
48     {
49       *(void **) argp = ecif->rvalue;
50       argp += 4;
51     }
52 
53   avn = ecif->cif->nargs;
54   p_argv = ecif->avalue;
55 
56   for (i = ecif->cif->nargs, p_arg = ecif->cif->arg_types;
57        (i != 0) && (avn != 0);
58        i--, p_arg++)
59     {
60       size_t z;
61 
62       /* Align if necessary.  */
63       if (((*p_arg)->alignment - 1) & (unsigned) argp)
64 	argp = (char *) ALIGN (argp, (*p_arg)->alignment);
65 
66       if (avn != 0)
67 	{
68 	  avn--;
69 	  z = (*p_arg)->size;
70 	  if (z < sizeof (int))
71 	    {
72 	      z = sizeof (int);
73 
74 	      switch ((*p_arg)->type)
75 		{
76 		case FFI_TYPE_SINT8:
77 		  *(signed int *) argp = (signed int)*(SINT8 *)(* p_argv);
78 		  break;
79 
80 		case FFI_TYPE_UINT8:
81 		  *(unsigned int *) argp = (unsigned int)*(UINT8 *)(* p_argv);
82 		  break;
83 
84 		case FFI_TYPE_SINT16:
85 		  *(signed int *) argp = (signed int)*(SINT16 *)(* p_argv);
86 		  break;
87 
88 		case FFI_TYPE_UINT16:
89 		  *(unsigned int *) argp = (unsigned int)*(UINT16 *)(* p_argv);
90 		  break;
91 
92 		case FFI_TYPE_STRUCT:
93 	  	  z = (*p_arg)->size;
94 	  	  if ((*p_arg)->alignment != 1)
95 		    memcpy (argp, *p_argv, z);
96 		  else
97 		    memcpy (argp + 4 - z, *p_argv, z);
98 	  	  z = sizeof (int);
99 		  break;
100 
101 		default:
102 		  FFI_ASSERT(0);
103 		}
104 	    }
105 	  else if (z == sizeof (int))
106 	    {
107 	       *(unsigned int *) argp = (unsigned int)*(UINT32 *)(* p_argv);
108 	    }
109 	  else
110 	    {
111 	      if ((*p_arg)->type == FFI_TYPE_STRUCT)
112 	        {
113 		  if (z > 8)
114 		    {
115 		      *(unsigned int *) argp = (unsigned int)(void *)(* p_argv);
116 		      z = sizeof(void *);
117 		    }
118 		  else
119 		    {
120 	              memcpy(argp, *p_argv, z);
121 		      z = 8;
122 		    }
123 	        }
124 	      else
125 	        {
126 		  /* Double or long long 64bit.  */
127 	          memcpy (argp, *p_argv, z);
128 	        }
129 	    }
130 	  p_argv++;
131 	  argp += z;
132 	}
133     }
134 
135   return;
136 }
137 
138 /* Perform machine dependent cif processing.  */
139 ffi_status
140 ffi_prep_cif_machdep(ffi_cif *cif)
141 {
142   /* Set the return type flag.  */
143   switch (cif->rtype->type)
144     {
145     case FFI_TYPE_VOID:
146       cif->flags = (unsigned) cif->rtype->type;
147       break;
148 
149     case FFI_TYPE_STRUCT:
150       if (cif->rtype->size <= 4)
151 	cif->flags = FFI_TYPE_INT;
152 
153       else if (cif->rtype->size <= 8)
154 	cif->flags = FFI_TYPE_DOUBLE;
155 
156       else
157 	cif->flags = (unsigned) cif->rtype->type;
158       break;
159 
160     case FFI_TYPE_SINT64:
161     case FFI_TYPE_UINT64:
162     case FFI_TYPE_DOUBLE:
163       cif->flags = FFI_TYPE_DOUBLE;
164       break;
165 
166     case FFI_TYPE_FLOAT:
167     default:
168       cif->flags = FFI_TYPE_INT;
169       break;
170     }
171 
172   return FFI_OK;
173 }
174 
175 extern void ffi_call_SYSV(void (*)(char *, extended_cif *), extended_cif *,
176 			  unsigned, unsigned, unsigned *, void (*fn)(void));
177 
178 void ffi_call(ffi_cif *cif, void (*fn)(void), void *rvalue, void **avalue)
179 {
180   extended_cif ecif;
181 
182   ecif.cif = cif;
183   ecif.avalue = avalue;
184 
185   /* If the return value is a struct and we don't have
186      a return value address then we need to make one.  */
187   if ((rvalue == NULL) &&
188       (cif->rtype->type == FFI_TYPE_STRUCT))
189     {
190       ecif.rvalue = alloca (cif->rtype->size);
191     }
192   else
193     ecif.rvalue = rvalue;
194 
195   switch (cif->abi)
196     {
197     case FFI_SYSV:
198       ffi_call_SYSV(ffi_prep_args, &ecif, cif->bytes,
199 		    cif->flags, ecif.rvalue, fn);
200       if (cif->rtype->type == FFI_TYPE_STRUCT)
201 	{
202 	  int size = cif->rtype->size;
203 	  int align = cif->rtype->alignment;
204 
205 	  if (size < 4)
206 	    {
207 	      if (align == 1)
208 	        *(unsigned long *)(ecif.rvalue) <<= (4 - size) * 8;
209 	    }
210 	  else if (4 < size && size < 8)
211 	    {
212 	      if (align == 1)
213 		{
214 		  memcpy (ecif.rvalue, ecif.rvalue + 8-size, size);
215 		}
216 	      else if (align == 2)
217 		{
218 		  if (size & 1)
219 		    size += 1;
220 
221 		  if (size != 8)
222 		    memcpy (ecif.rvalue, ecif.rvalue + 8-size, size);
223 		}
224 	    }
225 	}
226       break;
227 
228     default:
229       FFI_ASSERT(0);
230       break;
231     }
232 }
233