1 /* -----------------------------------------------------------------------
2 ffi.c - Copyright (c) 2012 Alexandre K. I. de Mendonca <alexandre.keunecke@gmail.com>
3
4 Blackfin Foreign Function Interface
5
6 Permission is hereby granted, free of charge, to any person obtaining
7 a copy of this software and associated documentation files (the
8 ``Software''), to deal in the Software without restriction, including
9 without limitation the rights to use, copy, modify, merge, publish,
10 distribute, sublicense, and/or sell copies of the Software, and to
11 permit persons to whom the Software is furnished to do so, subject to
12 the following conditions:
13
14 The above copyright notice and this permission notice shall be included
15 in all copies or substantial portions of the Software.
16
17 THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND,
18 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
19 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
20 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
21 HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
22 WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
23 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
24 DEALINGS IN THE SOFTWARE.
25 ----------------------------------------------------------------------- */
26 #include <ffi.h>
27 #include <ffi_common.h>
28
29 #include <stdlib.h>
30 #include <stdio.h>
31
32 /* Maximum number of GPRs available for argument passing. */
33 #define MAX_GPRARGS 3
34
35 /*
36 * Return types
37 */
38 #define FFIBFIN_RET_VOID 0
39 #define FFIBFIN_RET_BYTE 1
40 #define FFIBFIN_RET_HALFWORD 2
41 #define FFIBFIN_RET_INT64 3
42 #define FFIBFIN_RET_INT32 4
43
44 /*====================================================================*/
45 /* PROTOTYPE *
46 /*====================================================================*/
47 void ffi_prep_args(unsigned char *, extended_cif *);
48
49 /*====================================================================*/
50 /* Externals */
51 /* (Assembly) */
52 /*====================================================================*/
53
54 extern void ffi_call_SYSV(unsigned, extended_cif *, void(*)(unsigned char *, extended_cif *), unsigned, void *, void(*fn)(void));
55
56 /*====================================================================*/
57 /* Implementation */
58 /* */
59 /*====================================================================*/
60
61
62 /*
63 * This function calculates the return type (size) based on type.
64 */
65
ffi_prep_cif_machdep(ffi_cif * cif)66 ffi_status ffi_prep_cif_machdep(ffi_cif *cif)
67 {
68 /* --------------------------------------*
69 * Return handling *
70 * --------------------------------------*/
71 switch (cif->rtype->type) {
72 case FFI_TYPE_VOID:
73 cif->flags = FFIBFIN_RET_VOID;
74 break;
75 case FFI_TYPE_UINT16:
76 case FFI_TYPE_SINT16:
77 cif->flags = FFIBFIN_RET_HALFWORD;
78 break;
79 case FFI_TYPE_UINT8:
80 cif->flags = FFIBFIN_RET_BYTE;
81 break;
82 case FFI_TYPE_INT:
83 case FFI_TYPE_UINT32:
84 case FFI_TYPE_SINT32:
85 case FFI_TYPE_FLOAT:
86 case FFI_TYPE_POINTER:
87 case FFI_TYPE_SINT8:
88 cif->flags = FFIBFIN_RET_INT32;
89 break;
90 case FFI_TYPE_SINT64:
91 case FFI_TYPE_UINT64:
92 case FFI_TYPE_DOUBLE:
93 cif->flags = FFIBFIN_RET_INT64;
94 break;
95 case FFI_TYPE_STRUCT:
96 if (cif->rtype->size <= 4){
97 cif->flags = FFIBFIN_RET_INT32;
98 }else if (cif->rtype->size == 8){
99 cif->flags = FFIBFIN_RET_INT64;
100 }else{
101 //it will return via a hidden pointer in P0
102 cif->flags = FFIBFIN_RET_VOID;
103 }
104 break;
105 default:
106 FFI_ASSERT(0);
107 break;
108 }
109 return FFI_OK;
110 }
111
112 /*
113 * This will prepare the arguments and will call the assembly routine
114 * cif = the call interface
115 * fn = the function to be called
116 * rvalue = the return value
117 * avalue = the arguments
118 */
ffi_call(ffi_cif * cif,void (* fn)(void),void * rvalue,void ** avalue)119 void ffi_call(ffi_cif *cif, void(*fn)(void), void *rvalue, void **avalue)
120 {
121 int ret_type = cif->flags;
122 extended_cif ecif;
123 ecif.cif = cif;
124 ecif.avalue = avalue;
125 ecif.rvalue = rvalue;
126
127 switch (cif->abi) {
128 case FFI_SYSV:
129 ffi_call_SYSV(cif->bytes, &ecif, ffi_prep_args, ret_type, ecif.rvalue, fn);
130 break;
131 default:
132 FFI_ASSERT(0);
133 break;
134 }
135 }
136
137
138 /*
139 * This function prepares the parameters (copies them from the ecif to the stack)
140 * to call the function (ffi_prep_args is called by the assembly routine in file
141 * sysv.S, which also calls the actual function)
142 */
ffi_prep_args(unsigned char * stack,extended_cif * ecif)143 void ffi_prep_args(unsigned char *stack, extended_cif *ecif)
144 {
145 register unsigned int i = 0;
146 void **p_argv;
147 unsigned char *argp;
148 ffi_type **p_arg;
149 argp = stack;
150 p_argv = ecif->avalue;
151 for (i = ecif->cif->nargs, p_arg = ecif->cif->arg_types;
152 (i != 0);
153 i--, p_arg++) {
154 size_t z;
155 z = (*p_arg)->size;
156 if (z < sizeof(int)) {
157 z = sizeof(int);
158 switch ((*p_arg)->type) {
159 case FFI_TYPE_SINT8: {
160 signed char v = *(SINT8 *)(* p_argv);
161 signed int t = v;
162 *(signed int *) argp = t;
163 }
164 break;
165 case FFI_TYPE_UINT8: {
166 unsigned char v = *(UINT8 *)(* p_argv);
167 unsigned int t = v;
168 *(unsigned int *) argp = t;
169 }
170 break;
171 case FFI_TYPE_SINT16:
172 *(signed int *) argp = (signed int) * (SINT16 *)(* p_argv);
173 break;
174 case FFI_TYPE_UINT16:
175 *(unsigned int *) argp = (unsigned int) * (UINT16 *)(* p_argv);
176 break;
177 case FFI_TYPE_STRUCT:
178 memcpy(argp, *p_argv, (*p_arg)->size);
179 break;
180 default:
181 FFI_ASSERT(0);
182 break;
183 }
184 } else if (z == sizeof(int)) {
185 *(unsigned int *) argp = (unsigned int) * (UINT32 *)(* p_argv);
186 } else {
187 memcpy(argp, *p_argv, z);
188 }
189 p_argv++;
190 argp += z;
191 }
192 }
193
194
195
196