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

90 lines
2.0 KiB
ArmAsm

/* Copyright (C) 2011-2017 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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 <sysdep.h>
#include "ucontext_i.h"
/* int swapcontext (ucontext_t *oucp, const ucontext_t *ucp) */
.text
ENTRY (__swapcontext)
FEEDBACK_ENTER(__swapcontext)
/* Set up a frame and save r0 and r1. */
{
ST sp, lr
ADDI_PTR r11, sp, -(3 * REGSIZE)
move r10, sp
}
ADDI_PTR sp, sp, -(4 * REGSIZE)
cfi_def_cfa_offset (4 * REGSIZE)
cfi_offset (lr, 0)
{
ST r11, r10
ADDI_PTR r10, sp, (2 * REGSIZE)
}
{
ST r10, r0
ADDI_PTR r10, sp, (3 * REGSIZE)
}
ST r10, r1
/* Save the current context. */
jal __getcontext
/* Tear down the frame and restore r0, r1, and lr. */
{
BNEZ r0, .Lerror
ADDI_PTR r1, sp, 3 * REGSIZE
}
{
LD r1, r1
ADDI_PTR r0, sp, 2 * REGSIZE
}
{
LD r0, r0
ADDI_PTR sp, sp, 4 * REGSIZE
}
cfi_def_cfa_offset (0)
{
LD lr, sp
ADDLI_PTR r10, r0, UC_REG(54)
}
/* Update the stored sp and lr. */
{
ST r10, sp
ADDLI_PTR r10, r0, UC_REG(55)
}
ST r10, lr
/* Tail-call setcontext to finish up. */
{
move r0, r1
j __setcontext
}
.Lerror:
ADDI_PTR sp, sp, 4 * REGSIZE
cfi_def_cfa_offset (0)
LD lr, sp
jrp lr
END (__swapcontext)
weak_alias (__swapcontext, swapcontext)