Warning: That file was not part of the compilation database. It may have many parsing errors.

1/* Create new context.
2 Copyright (C) 2002-2019 Free Software Foundation, Inc.
3
4 This file is part of the GNU C Library.
5
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
10
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
15
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, see
18 <http://www.gnu.org/licenses/>. */
19
20#include <sysdep.h>
21#include <stdarg.h>
22#include <stdint.h>
23#include <ucontext.h>
24
25
26/* makecontext sets up a stack and the registers for the
27 user context. The stack looks like this:
28
29 +-----------------------+
30 | padding as required |
31 +-----------------------+
32 sp -> | parameter 7-n |
33 +-----------------------+
34
35 The registers are set up like this:
36 %x0 .. %x7: parameter 1 to 8
37 %x19 : uc_link
38 %sp : stack pointer.
39*/
40
41void
42__makecontext (ucontext_t *ucp, void (*func) (void), int argc, ...)
43{
44 extern void __startcontext (void);
45 uint64_t *sp;
46 va_list ap;
47 int i;
48
49 sp = (uint64_t *)
50 ((uintptr_t) ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size);
51
52 /* Allocate stack arguments. */
53 sp -= argc < 8 ? 0 : argc - 8;
54
55 /* Keep the stack aligned. */
56 sp = (uint64_t *) (((uintptr_t) sp) & -16L);
57
58 ucp->uc_mcontext.regs[19] = (uintptr_t) ucp->uc_link;
59 ucp->uc_mcontext.sp = (uintptr_t) sp;
60 ucp->uc_mcontext.pc = (uintptr_t) func;
61 ucp->uc_mcontext.regs[29] = (uintptr_t) 0;
62 ucp->uc_mcontext.regs[30] = (uintptr_t) &__startcontext;
63
64 va_start (ap, argc);
65 for (i = 0; i < argc; ++i)
66 if (i < 8)
67 ucp->uc_mcontext.regs[i] = va_arg (ap, uint64_t);
68 else
69 sp[i - 8] = va_arg (ap, uint64_t);
70
71 va_end (ap);
72}
73
74weak_alias (__makecontext, makecontext)
75

Warning: That file was not part of the compilation database. It may have many parsing errors.