1 /* -----------------------------------------------------------------------
2 ffi.c - Copyright (C) 2012 Anthony Green
4 Moxie Foreign Function Interface
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:
14 The above copyright notice and this permission notice shall be included
15 in all copies or substantial portions of the Software.
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 ----------------------------------------------------------------------- */
28 #include <ffi_common.h>
32 /* ffi_prep_args is called by the assembly routine once stack space
33 has been allocated for the function's arguments */
35 void *ffi_prep_args(char *stack, extended_cif *ecif)
37 register unsigned int i;
38 register void **p_argv;
40 register ffi_type **p_arg;
41 register int count = 0;
43 p_argv = ecif->avalue;
46 for (i = ecif->cif->nargs, p_arg = ecif->cif->arg_types;
54 if ((*p_arg)->type == FFI_TYPE_STRUCT)
57 *(void **) argp = *p_argv;
59 else if (z < sizeof(int))
62 switch ((*p_arg)->type)
65 *(signed int *) argp = (signed int)*(SINT8 *)(* p_argv);
69 *(unsigned int *) argp = (unsigned int)*(UINT8 *)(* p_argv);
73 *(signed int *) argp = (signed int)*(SINT16 *)(* p_argv);
77 *(unsigned int *) argp = (unsigned int)*(UINT16 *)(* p_argv);
84 else if (z == sizeof(int))
86 *(unsigned int *) argp = (unsigned int)*(UINT32 *)(* p_argv);
90 memcpy(argp, *p_argv, z);
97 return (stack + ((count > 24) ? 24 : ALIGN_DOWN(count, 8)));
100 /* Perform machine dependent cif processing */
101 ffi_status ffi_prep_cif_machdep(ffi_cif *cif)
103 if (cif->rtype->type == FFI_TYPE_STRUCT)
106 cif->flags = cif->rtype->size;
108 cif->bytes = ALIGN (cif->bytes, 8);
113 extern void ffi_call_EABI(void *(*)(char *, extended_cif *),
119 void ffi_call(ffi_cif *cif,
127 ecif.avalue = avalue;
129 /* If the return value is a struct and we don't have a return */
130 /* value address then we need to make one */
132 if ((rvalue == NULL) &&
133 (cif->rtype->type == FFI_TYPE_STRUCT))
135 ecif.rvalue = alloca(cif->rtype->size);
138 ecif.rvalue = rvalue;
144 ffi_call_EABI(ffi_prep_args, &ecif, cif->bytes,
145 cif->flags, ecif.rvalue, fn);
153 void ffi_closure_eabi (unsigned arg1, unsigned arg2, unsigned arg3,
154 unsigned arg4, unsigned arg5, unsigned arg6)
156 /* This function is called by a trampoline. The trampoline stows a
157 pointer to the ffi_closure object in gr7. We must save this
158 pointer in a place that will persist while we do our work. */
159 register ffi_closure *creg __asm__ ("$r7");
160 ffi_closure *closure = creg;
162 /* Arguments that don't fit in registers are found on the stack
163 at a fixed offset above the current frame pointer. */
164 register char *frame_pointer __asm__ ("$fp");
165 char *stack_args = frame_pointer + 16;
167 /* Lay the register arguments down in a continuous chunk of memory. */
168 unsigned register_args[6] =
169 { arg1, arg2, arg3, arg4, arg5, arg6 };
171 ffi_cif *cif = closure->cif;
172 ffi_type **arg_types = cif->arg_types;
173 void **avalue = alloca (cif->nargs * sizeof(void *));
174 char *ptr = (char *) register_args;
177 /* Find the address of each argument. */
178 for (i = 0; i < cif->nargs; i++)
180 switch (arg_types[i]->type)
186 case FFI_TYPE_SINT16:
187 case FFI_TYPE_UINT16:
190 case FFI_TYPE_SINT32:
191 case FFI_TYPE_UINT32:
195 case FFI_TYPE_STRUCT:
196 avalue[i] = *(void**)ptr;
199 /* This is an 8-byte value. */
206 /* If we've handled more arguments than fit in registers,
207 start looking at the those passed on the stack. */
208 if (ptr == ((char *)register_args + (6*4)))
212 /* Invoke the closure. */
213 if (cif->rtype->type == FFI_TYPE_STRUCT)
215 /* The caller allocates space for the return structure, and
216 passes a pointer to this space in gr3. Use this value directly
217 as the return value. */
218 register void *return_struct_ptr __asm__("$r0");
219 (closure->fun) (cif, return_struct_ptr, avalue, closure->user_data);
223 /* Allocate space for the return value and call the function. */
225 (closure->fun) (cif, &rvalue, avalue, closure->user_data);
227 /* Functions return 4-byte or smaller results in gr8. 8-byte
228 values also use gr9. We fill the both, even for small return
229 values, just to avoid a branch. */ /*
230 asm ("ldi @(%0, #0), gr8" : : "r" (&rvalue));
231 asm ("ldi @(%0, #0), gr9" : : "r" (&((int *) &rvalue)[1])); */
236 ffi_prep_closure_loc (ffi_closure* closure,
238 void (*fun)(ffi_cif*, void*, void**, void*),
242 unsigned int *tramp = (unsigned int *) &closure->tramp[0];
243 unsigned long fn = (long) ffi_closure_eabi;
244 unsigned long cls = (long) codeloc;
247 fn = (unsigned long) ffi_closure_eabi;
249 tramp[0] = 0x8cfc0000 + (fn & 0xffff); /* setlos lo(fn), gr6 */
250 tramp[1] = 0x8efc0000 + (cls & 0xffff); /* setlos lo(cls), gr7 */
251 tramp[2] = 0x8cf80000 + (fn >> 16); /* sethi hi(fn), gr6 */
252 tramp[3] = 0x8ef80000 + (cls >> 16); /* sethi hi(cls), gr7 */
253 tramp[4] = 0x80300006; /* jmpl @(gr0, gr6) */
257 closure->user_data = user_data;