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/*
* Copyright (C) 2016-2017 Andes Technology, Inc.
* Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
*/
/* Copyright (C) 2011-2013 Free Software Foundation, Inc.
Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library. If not, see
<http://www.gnu.org/licenses/>. */
#include <stdarg.h>
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <ucontext.h>
/* makecontext sets up a stack and the registers for the
user context. The stack looks like this:
+-----------------------+
| padding as required |
+-----------------------+
sp -> | parameter 7-n |
+-----------------------+
The registers are set up like this:
$r0 .. $r5: parameter 1 to 6
$r6 : uc_link
$sp : stack pointer.
*/
void
__makecontext (ucontext_t *ucp, void (*func) (void), int argc, ...)
{
extern void __startcontext (void);
unsigned long int *sp;
unsigned long *regptr;
va_list ap;
int i;
sp = (unsigned long int *)
((uintptr_t) ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size);
/* Allocate stack arguments. */
sp -= argc < 6 ? 0 : argc - 6;
/* Keep the stack aligned. */
sp = (unsigned long int *) (((uintptr_t) sp) & -8L);
ucp->uc_mcontext.nds32_r6 = (uintptr_t) ucp->uc_link;
ucp->uc_mcontext.nds32_sp = (uintptr_t) sp;
ucp->uc_mcontext.nds32_ipc = (uintptr_t) func;
ucp->uc_mcontext.nds32_lp = (uintptr_t) &__startcontext;
va_start (ap, argc);
regptr = &ucp->uc_mcontext.nds32_r0;
for (i = 0; i < argc; ++i)
if (i < 6)
*regptr++ = va_arg (ap, unsigned long int);
else
sp[i - 6] = va_arg (ap, unsigned long int);
va_end (ap);
}
weak_alias (__makecontext, makecontext)
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