mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-05 03:01:05 +00:00
79 lines
2.7 KiB
C
79 lines
2.7 KiB
C
/* Create new context. RISC-V version.
|
|
Copyright (C) 2001-2020 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
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
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <sysdep.h>
|
|
#include <sys/asm.h>
|
|
#include <sys/ucontext.h>
|
|
#include <stdarg.h>
|
|
#include <assert.h>
|
|
|
|
void
|
|
__makecontext (ucontext_t *ucp, void (*func) (void), int argc,
|
|
long int a0, long int a1, long int a2, long int a3, long int a4,
|
|
...)
|
|
{
|
|
extern void __start_context (void) attribute_hidden;
|
|
long int i, sp;
|
|
|
|
_Static_assert (REG_NARGS == 8, "__makecontext assumes 8 argument registers");
|
|
|
|
/* Set up the stack. */
|
|
sp = ((long int) ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size) & ALMASK;
|
|
|
|
/* Set up the register context.
|
|
ra = s0 = 0, terminating the stack for backtracing purposes.
|
|
s1 = the function we must call.
|
|
s2 = the subsequent context to run. */
|
|
ucp->uc_mcontext.__gregs[REG_RA] = 0;
|
|
ucp->uc_mcontext.__gregs[REG_S0] = 0;
|
|
ucp->uc_mcontext.__gregs[REG_S1] = (long int) func;
|
|
ucp->uc_mcontext.__gregs[REG_S2] = (long int) ucp->uc_link;
|
|
ucp->uc_mcontext.__gregs[REG_SP] = sp;
|
|
ucp->uc_mcontext.__gregs[REG_PC] = (long int) &__start_context;
|
|
|
|
/* Put args in a0-a7, then put any remaining args on the stack. */
|
|
ucp->uc_mcontext.__gregs[REG_A0 + 0] = a0;
|
|
ucp->uc_mcontext.__gregs[REG_A0 + 1] = a1;
|
|
ucp->uc_mcontext.__gregs[REG_A0 + 2] = a2;
|
|
ucp->uc_mcontext.__gregs[REG_A0 + 3] = a3;
|
|
ucp->uc_mcontext.__gregs[REG_A0 + 4] = a4;
|
|
|
|
if (__glibc_unlikely (argc > 5))
|
|
{
|
|
va_list vl;
|
|
va_start (vl, a4);
|
|
|
|
long reg_args = argc < REG_NARGS ? argc : REG_NARGS;
|
|
for (i = 5; i < reg_args; i++)
|
|
ucp->uc_mcontext.__gregs[REG_A0 + i] = va_arg (vl, long);
|
|
|
|
long int stack_args = argc - reg_args;
|
|
if (stack_args > 0)
|
|
{
|
|
sp = (sp - stack_args * sizeof (long int)) & ALMASK;
|
|
ucp->uc_mcontext.__gregs[REG_SP] = sp;
|
|
for (i = 0; i < stack_args; i++)
|
|
((long int *) sp)[i] = va_arg (vl, long int);
|
|
}
|
|
|
|
va_end (vl);
|
|
}
|
|
}
|
|
|
|
weak_alias (__makecontext, makecontext)
|