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
ffi_prep_types(ffi_abi abi)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
ffi_prep_cif_machdep(ffi_cif * cif)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
ffi_prep_cif_machdep_var(ffi_cif * cif,unsigned int nfixedargs MAYBE_UNUSED,unsigned int ntotalargs MAYBE_UNUSED)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 void
ffi_call(ffi_cif * cif,void (* fn)(void),void * rvalue,void ** avalue)74 ffi_call(ffi_cif *cif, void (*fn)(void), void *rvalue, void **avalue)
75 {
76 /* The final SYSV ABI says that structures smaller or equal 8 bytes
77 are returned in r3/r4. A draft ABI used by linux instead returns
78 them in memory.
79
80 We bounce-buffer SYSV small struct return values so that sysv.S
81 can write r3 and r4 to memory without worrying about struct size.
82
83 For ELFv2 ABI, use a bounce buffer for homogeneous structs too,
84 for similar reasons. */
85 unsigned long smst_buffer[8];
86 extended_cif ecif;
87
88 ecif.cif = cif;
89 ecif.avalue = avalue;
90
91 ecif.rvalue = rvalue;
92 if ((cif->flags & FLAG_RETURNS_SMST) != 0)
93 ecif.rvalue = smst_buffer;
94 /* Ensure that we have a valid struct return value.
95 FIXME: Isn't this just papering over a user problem? */
96 else if (!rvalue && cif->rtype->type == FFI_TYPE_STRUCT)
97 ecif.rvalue = alloca (cif->rtype->size);
98
99 #ifdef POWERPC64
100 ffi_call_LINUX64 (&ecif, -(long) cif->bytes, cif->flags, ecif.rvalue, fn);
101 #else
102 ffi_call_SYSV (&ecif, -cif->bytes, cif->flags, ecif.rvalue, fn);
103 #endif
104
105 /* Check for a bounce-buffered return value */
106 if (rvalue && ecif.rvalue == smst_buffer)
107 {
108 unsigned int rsize = cif->rtype->size;
109 #ifndef __LITTLE_ENDIAN__
110 /* The SYSV ABI returns a structure of up to 4 bytes in size
111 left-padded in r3. */
112 # ifndef POWERPC64
113 if (rsize <= 4)
114 memcpy (rvalue, (char *) smst_buffer + 4 - rsize, rsize);
115 else
116 # endif
117 /* The SYSV ABI returns a structure of up to 8 bytes in size
118 left-padded in r3/r4, and the ELFv2 ABI similarly returns a
119 structure of up to 8 bytes in size left-padded in r3. */
120 if (rsize <= 8)
121 memcpy (rvalue, (char *) smst_buffer + 8 - rsize, rsize);
122 else
123 #endif
124 memcpy (rvalue, smst_buffer, rsize);
125 }
126 }
127
128
129 ffi_status
ffi_prep_closure_loc(ffi_closure * closure,ffi_cif * cif,void (* fun)(ffi_cif *,void *,void **,void *),void * user_data,void * codeloc)130 ffi_prep_closure_loc (ffi_closure *closure,
131 ffi_cif *cif,
132 void (*fun) (ffi_cif *, void *, void **, void *),
133 void *user_data,
134 void *codeloc)
135 {
136 #ifdef POWERPC64
137 return ffi_prep_closure_loc_linux64 (closure, cif, fun, user_data, codeloc);
138 #else
139 return ffi_prep_closure_loc_sysv (closure, cif, fun, user_data, codeloc);
140 #endif
141 }
142