glibc/sysdeps/unix/sysv/linux/hppa/swapcontext.S

73 lines
1.8 KiB
ArmAsm

/* Swap to new context.
Copyright (C) 2008-2023 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"
.text
ENTRY(__swapcontext)
/* Copy rp to ret0 (r28). */
copy %rp,%ret0
/* Create a frame. */
ldo 64(%sp),%sp
.cfi_def_cfa_offset -64
/* Save the current machine context to oucp. */
bl __getcontext,%rp
/* Copy oucp to register ret1 (r29). __getcontext saves and
restores it on a normal return. It is restored from oR29
on reactivation. */
copy %r26,%ret1
/* Pop frame. */
ldo -64(%sp),%sp
.cfi_def_cfa_offset 0
/* Load return pointer from oR28. */
ldw oR28(%ret1),%rp
/* Return if error. */
or,= %r0,%ret0,%r0
bv,n %r0(%rp)
/* Load sc_sar flag. */
ldb oSAR(%ret1),%r20
/* Return if oucp context has been reactivated. */
or,= %r0,%r20,%r0
bv,n %r0(%rp)
/* Mark sc_sar flag. */
ldi 1,%r20
stb %r20,oSAR(%ret1)
/* Activate the machine context in ucp. */
bl __setcontext,%rp
ldw oR25(%ret1),%r26
/* Load return pointer. */
ldw oR28(%ret1),%rp
bv,n %r0(%rp)
END(__swapcontext)
weak_alias (__swapcontext, swapcontext)