1 /* Copyright (C) 2001-2017 Free Software Foundation, Inc.
2 This file is part of the GNU C Library.
3 Contributed by Jakub Jelinek <jakub@redhat.com>.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <http://www.gnu.org/licenses/>. */
24 extern void __start_context (struct ucontext
*ucp
);
27 __makecontext (ucontext_t
*ucp
, void (*func
) (void), int argc
, ...)
29 extern void __makecontext_ret (void);
30 unsigned long *sp
, *topsp
;
34 sp
= (unsigned long *) ((long) ucp
->uc_stack
.ss_sp
+ ucp
->uc_stack
.ss_size
);
35 sp
-= (argc
> 6 ? argc
: 6) + 32;
36 sp
= (unsigned long *) (((long) sp
) & -16L);
37 topsp
= sp
+ (argc
> 6 ? argc
: 6) + 16;
39 ucp
->uc_mcontext
.mc_gregs
[MC_PC
] = (long) func
;
40 ucp
->uc_mcontext
.mc_gregs
[MC_NPC
] = ((long) func
) + 4;
41 ucp
->uc_mcontext
.mc_gregs
[MC_O6
] = ((long) sp
) - 0x7ff;
42 ucp
->uc_mcontext
.mc_gregs
[MC_O7
] = ((long) __start_context
) - 8;
43 ucp
->uc_mcontext
.mc_fp
= ((long) topsp
) - 0x7ff;
44 ucp
->uc_mcontext
.mc_i7
= 0;
47 sp
[8] = (long) ucp
->uc_link
;
49 for (i
= 0; i
< argc
; ++i
)
51 ucp
->uc_mcontext
.mc_gregs
[MC_O0
+ i
] = va_arg (ap
, long);
53 sp
[16 + i
] = va_arg (ap
, long);
57 weak_alias (__makecontext
, makecontext
)