1 /* -----------------------------------------------------------------------
2 prep_cif.c - Copyright (c) 2011, 2012, 2021 Anthony Green
3 Copyright (c) 1996, 1998, 2007 Red Hat, Inc.
4
5 Permission is hereby granted, free of charge, to any person obtaining
6 a copy of this software and associated documentation files (the
7 ``Software''), to deal in the Software without restriction, including
8 without limitation the rights to use, copy, modify, merge, publish,
9 distribute, sublicense, and/or sell copies of the Software, and to
10 permit persons to whom the Software is furnished to do so, subject to
11 the following conditions:
12
13 The above copyright notice and this permission notice shall be included
14 in all copies or substantial portions of the Software.
15
16 THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND,
17 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
20 HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
21 WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
23 DEALINGS IN THE SOFTWARE.
24 ----------------------------------------------------------------------- */
25
26 #include <ffi.h>
27 #include <ffi_common.h>
28 #include <stdlib.h>
29
30 /* Round up to FFI_SIZEOF_ARG. */
31
32 #define STACK_ARG_SIZE(x) FFI_ALIGN(x, FFI_SIZEOF_ARG)
33
34 /* Perform machine independent initialization of aggregate type
35 specifications. */
36
37 static ffi_status initialize_aggregate(ffi_type *arg, size_t *offsets)
38 {
39 ffi_type **ptr;
40
41 if (UNLIKELY(arg == NULL || arg->elements == NULL))
42 return FFI_BAD_TYPEDEF;
43
44 arg->size = 0;
45 arg->alignment = 0;
46
47 ptr = &(arg->elements[0]);
48
49 if (UNLIKELY(ptr == 0))
50 return FFI_BAD_TYPEDEF;
51
52 while ((*ptr) != NULL)
53 {
54 if (UNLIKELY(((*ptr)->size == 0)
55 && (initialize_aggregate((*ptr), NULL) != FFI_OK)))
56 return FFI_BAD_TYPEDEF;
57
58 /* Perform a sanity check on the argument type */
59 FFI_ASSERT_VALID_TYPE(*ptr);
60
61 arg->size = FFI_ALIGN(arg->size, (*ptr)->alignment);
62 if (offsets)
63 *offsets++ = arg->size;
64 arg->size += (*ptr)->size;
65
66 arg->alignment = (arg->alignment > (*ptr)->alignment) ?
67 arg->alignment : (*ptr)->alignment;
68
69 ptr++;
70 }
71
72 /* Structure size includes tail padding. This is important for
73 structures that fit in one register on ABIs like the PowerPC64
74 Linux ABI that right justify small structs in a register.
75 It's also needed for nested structure layout, for example
76 struct A { long a; char b; }; struct B { struct A x; char y; };
77 should find y at an offset of 2*sizeof(long) and result in a
78 total size of 3*sizeof(long). */
79 arg->size = FFI_ALIGN (arg->size, arg->alignment);
80
81 /* On some targets, the ABI defines that structures have an additional
82 alignment beyond the "natural" one based on their elements. */
83 #ifdef FFI_AGGREGATE_ALIGNMENT
84 if (FFI_AGGREGATE_ALIGNMENT > arg->alignment)
85 arg->alignment = FFI_AGGREGATE_ALIGNMENT;
86 #endif
87
88 if (arg->size == 0)
89 return FFI_BAD_TYPEDEF;
90 else
91 return FFI_OK;
92 }
93
94 #ifndef __CRIS__
95 /* The CRIS ABI specifies structure elements to have byte
96 alignment only, so it completely overrides this functions,
97 which assumes "natural" alignment and padding. */
98
99 /* Perform machine independent ffi_cif preparation, then call
100 machine dependent routine. */
101
102 /* For non variadic functions isvariadic should be 0 and
103 nfixedargs==ntotalargs.
104
105 For variadic calls, isvariadic should be 1 and nfixedargs
106 and ntotalargs set as appropriate. nfixedargs must always be >=1 */
107
108
109 ffi_status FFI_HIDDEN ffi_prep_cif_core(ffi_cif *cif, ffi_abi abi,
110 unsigned int isvariadic,
111 unsigned int nfixedargs,
112 unsigned int ntotalargs,
113 ffi_type *rtype, ffi_type **atypes)
114 {
115 unsigned bytes = 0;
116 unsigned int i;
117 ffi_type **ptr;
118
119 FFI_ASSERT(cif != NULL);
120 FFI_ASSERT((!isvariadic) || (nfixedargs >= 1));
121 FFI_ASSERT(nfixedargs <= ntotalargs);
122
123 if (! (abi > FFI_FIRST_ABI && abi < FFI_LAST_ABI))
124 return FFI_BAD_ABI;
125
126 cif->abi = abi;
127 cif->arg_types = atypes;
128 cif->nargs = ntotalargs;
129 cif->rtype = rtype;
130
131 cif->flags = 0;
132 #if (defined(_M_ARM64) || defined(__aarch64__)) && defined(_WIN32)
133 cif->is_variadic = isvariadic;
134 #endif
135 #if HAVE_LONG_DOUBLE_VARIANT
136 ffi_prep_types (abi);
137 #endif
138
139 /* Initialize the return type if necessary */
140 if ((cif->rtype->size == 0)
141 && (initialize_aggregate(cif->rtype, NULL) != FFI_OK))
142 return FFI_BAD_TYPEDEF;
143
144 #ifndef FFI_TARGET_HAS_COMPLEX_TYPE
145 if (rtype->type == FFI_TYPE_COMPLEX)
146 abort();
147 #endif
148 /* Perform a sanity check on the return type */
149 FFI_ASSERT_VALID_TYPE(cif->rtype);
150
151 /* x86, x86-64 and s390 stack space allocation is handled in prep_machdep. */
152 #if !defined FFI_TARGET_SPECIFIC_STACK_SPACE_ALLOCATION
153 /* Make space for the return structure pointer */
154 if (cif->rtype->type == FFI_TYPE_STRUCT
155 #ifdef TILE
156 && (cif->rtype->size > 10 * FFI_SIZEOF_ARG)
157 #endif
158 #ifdef XTENSA
159 && (cif->rtype->size > 16)
160 #endif
161 #ifdef NIOS2
162 && (cif->rtype->size > 8)
163 #endif
164 )
165 bytes = STACK_ARG_SIZE(sizeof(void*));
166 #endif
167
168 for (ptr = cif->arg_types, i = cif->nargs; i > 0; i--, ptr++)
169 {
170
171 /* Initialize any uninitialized aggregate type definitions */
172 if (((*ptr)->size == 0)
173 && (initialize_aggregate((*ptr), NULL) != FFI_OK))
174 return FFI_BAD_TYPEDEF;
175
176 #ifndef FFI_TARGET_HAS_COMPLEX_TYPE
177 if ((*ptr)->type == FFI_TYPE_COMPLEX)
178 abort();
179 #endif
180 /* Perform a sanity check on the argument type, do this
181 check after the initialization. */
182 FFI_ASSERT_VALID_TYPE(*ptr);
183
184 #if !defined FFI_TARGET_SPECIFIC_STACK_SPACE_ALLOCATION
185 {
186 /* Add any padding if necessary */
187 if (((*ptr)->alignment - 1) & bytes)
188 bytes = (unsigned)FFI_ALIGN(bytes, (*ptr)->alignment);
189
190 #ifdef TILE
191 if (bytes < 10 * FFI_SIZEOF_ARG &&
192 bytes + STACK_ARG_SIZE((*ptr)->size) > 10 * FFI_SIZEOF_ARG)
193 {
194 /* An argument is never split between the 10 parameter
195 registers and the stack. */
196 bytes = 10 * FFI_SIZEOF_ARG;
197 }
198 #endif
199 #ifdef XTENSA
200 if (bytes <= 6*4 && bytes + STACK_ARG_SIZE((*ptr)->size) > 6*4)
201 bytes = 6*4;
202 #endif
203
204 bytes += (unsigned int)STACK_ARG_SIZE((*ptr)->size);
205 }
206 #endif
207 }
208
209 cif->bytes = bytes;
210
211 /* Perform machine dependent cif processing */
212 #ifdef FFI_TARGET_SPECIFIC_VARIADIC
213 if (isvariadic)
214 return ffi_prep_cif_machdep_var(cif, nfixedargs, ntotalargs);
215 #endif
216
217 return ffi_prep_cif_machdep(cif);
218 }
219 #endif /* not __CRIS__ */
220
221 ffi_status ffi_prep_cif(ffi_cif *cif, ffi_abi abi, unsigned int nargs,
222 ffi_type *rtype, ffi_type **atypes)
223 {
224 return ffi_prep_cif_core(cif, abi, 0, nargs, nargs, rtype, atypes);
225 }
226
227 ffi_status ffi_prep_cif_var(ffi_cif *cif,
228 ffi_abi abi,
229 unsigned int nfixedargs,
230 unsigned int ntotalargs,
231 ffi_type *rtype,
232 ffi_type **atypes)
233 {
234 ffi_status rc;
235 size_t int_size = ffi_type_sint.size;
236 int i;
237
238 rc = ffi_prep_cif_core(cif, abi, 1, nfixedargs, ntotalargs, rtype, atypes);
239
240 if (rc != FFI_OK)
241 return rc;
242
243 for (i = 1; i < ntotalargs; i++)
244 {
245 ffi_type *arg_type = atypes[i];
246 if (arg_type == &ffi_type_float
247 || ((arg_type->type != FFI_TYPE_STRUCT
248 && arg_type->type != FFI_TYPE_COMPLEX)
249 && arg_type->size < int_size))
250 return FFI_BAD_ARGTYPE;
251 }
252
253 return FFI_OK;
254 }
255
256 #if FFI_CLOSURES
257
258 ffi_status
259 ffi_prep_closure (ffi_closure* closure,
260 ffi_cif* cif,
261 void (*fun)(ffi_cif*,void*,void**,void*),
262 void *user_data)
263 {
264 return ffi_prep_closure_loc (closure, cif, fun, user_data, closure);
265 }
266
267 #endif
268
269 ffi_status
270 ffi_get_struct_offsets (ffi_abi abi, ffi_type *struct_type, size_t *offsets)
271 {
272 if (! (abi > FFI_FIRST_ABI && abi < FFI_LAST_ABI))
273 return FFI_BAD_ABI;
274 if (struct_type->type != FFI_TYPE_STRUCT)
275 return FFI_BAD_TYPEDEF;
276
277 #if HAVE_LONG_DOUBLE_VARIANT
278 ffi_prep_types (abi);
279 #endif
280
281 return initialize_aggregate(struct_type, offsets);
282 }