1 /* -----------------------------------------------------------------------
2 ffi.c - Copyright (C) 2013 IBM
3 Copyright (C) 2011 Anthony Green
4 Copyright (C) 2011 Kyle Moffett
5 Copyright (C) 2008 Red Hat, Inc
6 Copyright (C) 2007, 2008 Free Software Foundation, Inc
7 Copyright (c) 1998 Geoffrey Keating
8
9 PowerPC Foreign Function Interface
10
11 Permission is hereby granted, free of charge, to any person obtaining
12 a copy of this software and associated documentation files (the
13 ``Software''), to deal in the Software without restriction, including
14 without limitation the rights to use, copy, modify, merge, publish,
15 distribute, sublicense, and/or sell copies of the Software, and to
16 permit persons to whom the Software is furnished to do so, subject to
17 the following conditions:
18
19 The above copyright notice and this permission notice shall be included
20 in all copies or substantial portions of the Software.
21
22 THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, EXPRESS
23 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
24 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
25 IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR
26 OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
27 ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
28 OTHER DEALINGS IN THE SOFTWARE.
29 ----------------------------------------------------------------------- */
30
31 #include "ffi.h"
32 #include "ffi_common.h"
33 #include "ffi_powerpc.h"
34
35 #if HAVE_LONG_DOUBLE_VARIANT
36 /* Adjust ffi_type_longdouble. */
37 void FFI_HIDDEN
38 ffi_prep_types (ffi_abi abi)
39 {
40 # if FFI_TYPE_LONGDOUBLE != FFI_TYPE_DOUBLE
41 # ifdef POWERPC64
42 ffi_prep_types_linux64 (abi);
43 # else
44 ffi_prep_types_sysv (abi);
45 # endif
46 # endif
47 }
48 #endif
49
50 /* Perform machine dependent cif processing */
51 ffi_status FFI_HIDDEN
52 ffi_prep_cif_machdep (ffi_cif *cif)
53 {
54 #ifdef POWERPC64
55 return ffi_prep_cif_linux64 (cif);
56 #else
57 return ffi_prep_cif_sysv (cif);
58 #endif
59 }
60
61 ffi_status FFI_HIDDEN
62 ffi_prep_cif_machdep_var (ffi_cif *cif,
63 unsigned int nfixedargs MAYBE_UNUSED,
64 unsigned int ntotalargs MAYBE_UNUSED)
65 {
66 #ifdef POWERPC64
67 return ffi_prep_cif_linux64_var (cif, nfixedargs, ntotalargs);
68 #else
69 return ffi_prep_cif_sysv (cif);
70 #endif
71 }
72
73 static void
74 ffi_call_int (ffi_cif *cif,
75 void (*fn) (void),
76 void *rvalue,
77 void **avalue,
78 void *closure)
79 {
80 /* The final SYSV ABI says that structures smaller or equal 8 bytes
81 are returned in r3/r4. A draft ABI used by linux instead returns
82 them in memory.
83
84 We bounce-buffer SYSV small struct return values so that sysv.S
85 can write r3 and r4 to memory without worrying about struct size.
86
87 For ELFv2 ABI, use a bounce buffer for homogeneous structs too,
88 for similar reasons. This bounce buffer must be aligned to 16
89 bytes for use with homogeneous structs of vectors (float128). */
90 float128 smst_buffer[8];
91 extended_cif ecif;
92
93 ecif.cif = cif;
94 ecif.avalue = avalue;
95
96 ecif.rvalue = rvalue;
97 if ((cif->flags & FLAG_RETURNS_SMST) != 0)
98 ecif.rvalue = smst_buffer;
99 /* Ensure that we have a valid struct return value.
100 FIXME: Isn't this just papering over a user problem? */
101 else if (!rvalue && cif->rtype->type == FFI_TYPE_STRUCT)
102 ecif.rvalue = alloca (cif->rtype->size);
103
104 #ifdef POWERPC64
105 ffi_call_LINUX64 (&ecif, fn, ecif.rvalue, cif->flags, closure,
106 -(long) cif->bytes);
107 #else
108 ffi_call_SYSV (&ecif, fn, ecif.rvalue, cif->flags, closure, -cif->bytes);
109 #endif
110
111 /* Check for a bounce-buffered return value */
112 if (rvalue && ecif.rvalue == smst_buffer)
113 {
114 unsigned int rsize = cif->rtype->size;
115 #ifndef __LITTLE_ENDIAN__
116 /* The SYSV ABI returns a structure of up to 4 bytes in size
117 left-padded in r3. */
118 # ifndef POWERPC64
119 if (rsize <= 4)
120 memcpy (rvalue, (char *) smst_buffer + 4 - rsize, rsize);
121 else
122 # endif
123 /* The SYSV ABI returns a structure of up to 8 bytes in size
124 left-padded in r3/r4, and the ELFv2 ABI similarly returns a
125 structure of up to 8 bytes in size left-padded in r3. But
126 note that a structure of a single float is not paddded. */
127 if (rsize <= 8 && (cif->flags & FLAG_RETURNS_FP) == 0)
128 memcpy (rvalue, (char *) smst_buffer + 8 - rsize, rsize);
129 else
130 #endif
131 memcpy (rvalue, smst_buffer, rsize);
132 }
133 }
134
135 void
136 ffi_call (ffi_cif *cif, void (*fn) (void), void *rvalue, void **avalue)
137 {
138 ffi_call_int (cif, fn, rvalue, avalue, NULL);
139 }
140
141 void
142 ffi_call_go (ffi_cif *cif, void (*fn) (void), void *rvalue, void **avalue,
143 void *closure)
144 {
145 ffi_call_int (cif, fn, rvalue, avalue, closure);
146 }
147
148 ffi_status
149 ffi_prep_closure_loc (ffi_closure *closure,
150 ffi_cif *cif,
151 void (*fun) (ffi_cif *, void *, void **, void *),
152 void *user_data,
153 void *codeloc)
154 {
155 #ifdef POWERPC64
156 return ffi_prep_closure_loc_linux64 (closure, cif, fun, user_data, codeloc);
157 #else
158 return ffi_prep_closure_loc_sysv (closure, cif, fun, user_data, codeloc);
159 #endif
160 }
161
162 ffi_status
163 ffi_prep_go_closure (ffi_go_closure *closure,
164 ffi_cif *cif,
165 void (*fun) (ffi_cif *, void *, void **, void *))
166 {
167 #ifdef POWERPC64
168 closure->tramp = ffi_go_closure_linux64;
169 #else
170 closure->tramp = ffi_go_closure_sysv;
171 #endif
172 closure->cif = cif;
173 closure->fun = fun;
174 return FFI_OK;
175 }