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/* Modify saved context.
Copyright (C) 2015-2022 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 "ucontext_i.h"
/* int swapcontext (ucontext_t *oucp, const ucontext_t *ucp) */
.text
ENTRY(__swapcontext)
/* Same as getcontext(). */
stw r16, (UCONTEXT_MCONTEXT + 16*4)(r4)
stw r17, (UCONTEXT_MCONTEXT + 17*4)(r4)
stw r18, (UCONTEXT_MCONTEXT + 18*4)(r4)
stw r19, (UCONTEXT_MCONTEXT + 19*4)(r4)
stw r20, (UCONTEXT_MCONTEXT + 20*4)(r4)
stw r21, (UCONTEXT_MCONTEXT + 21*4)(r4)
stw r22, (UCONTEXT_MCONTEXT + 22*4)(r4)
stw ra, (UCONTEXT_MCONTEXT + 24*4)(r4)
stw fp, (UCONTEXT_MCONTEXT + 25*4)(r4)
stw gp, (UCONTEXT_MCONTEXT + 26*4)(r4)
/* Store return address at place for EA. */
stw ra, (UCONTEXT_MCONTEXT + 28*4)(r4)
stw sp, (UCONTEXT_MCONTEXT + 29*4)(r4)
/* Store zero for return success. */
stw zero, (UCONTEXT_MCONTEXT + 2*4)(r4)
/* Store value "1" at uc_flags to recognize as getcontext created. */
movi r2, 1
stw r2, UCONTEXT_FLAGS(r4)
/* Store MCONTEXT_VERSION at first word of mcontext_t. */
movi r2, MCONTEXT_VERSION
stw r2, UCONTEXT_MCONTEXT(r4)
/* Save ucp to non-argument syscall preserved register. */
mov r10, r5
/* Get signal mask. */
/* rt_sigprocmask (SIG_BLOCK, NULL, &ucp->uc_sigmask, _NSIG8) */
movi r7, _NSIG8
addi r6, r4, UCONTEXT_SIGMASK
mov r5, zero
movi r4, SIG_BLOCK
movi r2, SYS_ify (rt_sigprocmask)
trap
bne r7, zero, SYSCALL_ERROR_LABEL
/* Same as setcontext(). */
ldw r5, UCONTEXT_FLAGS(r10)
movi r6, 1
bne r5, r6, .Lsigreturn
/* Restore signal mask. */
/* rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, NULL, _NSIG8) */
movi r7, _NSIG8
addi r5, r10, UCONTEXT_SIGMASK
mov r6, zero
movi r4, SIG_SETMASK
movi r2, SYS_ify (rt_sigprocmask)
trap
bne r7, zero, SYSCALL_ERROR_LABEL
/* Restore argument registers, for the makecontext() case. */
ldw r4, (UCONTEXT_MCONTEXT + 4*4)(r10)
ldw r5, (UCONTEXT_MCONTEXT + 5*4)(r10)
ldw r6, (UCONTEXT_MCONTEXT + 6*4)(r10)
ldw r7, (UCONTEXT_MCONTEXT + 7*4)(r10)
ldw r16, (UCONTEXT_MCONTEXT + 16*4)(r10)
ldw r17, (UCONTEXT_MCONTEXT + 17*4)(r10)
ldw r18, (UCONTEXT_MCONTEXT + 18*4)(r10)
ldw r19, (UCONTEXT_MCONTEXT + 19*4)(r10)
ldw r20, (UCONTEXT_MCONTEXT + 20*4)(r10)
ldw r21, (UCONTEXT_MCONTEXT + 21*4)(r10)
ldw r22, (UCONTEXT_MCONTEXT + 22*4)(r10)
ldw ra, (UCONTEXT_MCONTEXT + 24*4)(r10)
ldw fp, (UCONTEXT_MCONTEXT + 25*4)(r10)
ldw gp, (UCONTEXT_MCONTEXT + 26*4)(r10)
/* Load address to continue execution. */
ldw r3, (UCONTEXT_MCONTEXT + 28*4)(r10)
ldw sp, (UCONTEXT_MCONTEXT + 29*4)(r10)
mov r2, zero
jmp r3
.Lsigreturn:
addi sp, sp, -RT_SIGFRAME_SIZE
cfi_adjust_cfa_offset (RT_SIGFRAME_SIZE)
addi r2, sp, RT_SIGFRAME_UCONTEXT
movi r3, UCONTEXT_SIZE-4
1:
add r6, r4, r3
ldw r5, 0(r6)
add r7, r2, r3
addi r3, r3, -4
stw r5, 0(r7)
bgt r3, zero, 1b
movi r2, SYS_ify (rt_sigreturn)
trap
addi sp, sp, RT_SIGFRAME_SIZE
cfi_adjust_cfa_offset (-RT_SIGFRAME_SIZE)
br SYSCALL_ERROR_LABEL
PSEUDO_END (__swapcontext)
weak_alias (__swapcontext, swapcontext)
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