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/* Set current context.
Copyright (C) 2009-2014 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
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
#include "ucontext_i.h"
#include "ucontext-internal.h"
/* int __setcontext (const ucontext_t *ucp)
Restores the machine context in UCP and thereby resumes execution
in that context.
This implementation is intended to be used for *synchronous* context
switches only. Therefore, it does not have to restore anything
other than the PRESERVED state. */
.text
ENTRY (__setcontext)
/* Save a copy of UCP. */
mov x9, x0
/* Set the signal mask with
rt_sigprocmask (SIG_SETMASK, mask, NULL, _NSIG/8). */
mov x0, #SIG_SETMASK
add x1, x9, #UCONTEXT_SIGMASK
mov x2, #0
mov x3, #_NSIG8
mov x8, SYS_ify (rt_sigprocmask)
svc 0
cbz x0, 1f
b C_SYMBOL_NAME (__syscall_error)
1:
/* Restore the general purpose registers. */
mov x0, x9
cfi_def_cfa (x0, 0)
cfi_offset (x18, oX0 + 18 * SZREG)
cfi_offset (x19, oX0 + 19 * SZREG)
cfi_offset (x20, oX0 + 20 * SZREG)
cfi_offset (x21, oX0 + 21 * SZREG)
cfi_offset (x22, oX0 + 22 * SZREG)
cfi_offset (x23, oX0 + 23 * SZREG)
cfi_offset (x24, oX0 + 24 * SZREG)
cfi_offset (x25, oX0 + 25 * SZREG)
cfi_offset (x26, oX0 + 26 * SZREG)
cfi_offset (x27, oX0 + 27 * SZREG)
cfi_offset (x28, oX0 + 28 * SZREG)
cfi_offset (x29, oX0 + 29 * SZREG)
cfi_offset (x30, oX0 + 30 * SZREG)
cfi_offset ( d8, oV0 + 8 * SZVREG)
cfi_offset ( d9, oV0 + 9 * SZVREG)
cfi_offset (d10, oV0 + 10 * SZVREG)
cfi_offset (d11, oV0 + 11 * SZVREG)
cfi_offset (d12, oV0 + 12 * SZVREG)
cfi_offset (d13, oV0 + 13 * SZVREG)
cfi_offset (d14, oV0 + 14 * SZVREG)
cfi_offset (d15, oV0 + 15 * SZVREG)
ldp x18, x19, [x0, oX0 + 18 * SZREG]
ldp x20, x21, [x0, oX0 + 20 * SZREG]
ldp x22, x23, [x0, oX0 + 22 * SZREG]
ldp x24, x25, [x0, oX0 + 24 * SZREG]
ldp x26, x27, [x0, oX0 + 26 * SZREG]
ldp x28, x29, [x0, oX0 + 28 * SZREG]
ldr x30, [x0, oX0 + 30 * SZREG]
ldr x2, [x0, oSP]
mov sp, x2
/* Check for FP SIMD context. */
add x2, x0, #oEXTENSION
mov w3, #(FPSIMD_MAGIC & 0xffff)
movk w3, #(FPSIMD_MAGIC >> 16), lsl #16
ldr w1, [x2, #oHEAD + oMAGIC]
cmp w1, w3
b.ne 2f
/* Restore the FP SIMD context. */
add x3, x2, #oV0 + 8 * SZVREG
ldp d8, d9, [x3], #2 * SZVREG
ldp d10, d11, [x3], #2 * SZVREG
ldp d12, d13, [x3], #2 * SZVREG
ldp d14, d15, [x3], #2 * SZVREG
add x3, x2, oFPSR
ldr w4, [x3]
msr fpsr, x4
ldr w4, [x3, oFPCR - oFPSR]
msr fpcr, x4
2:
ldr x16, [x0, oPC]
/* Restore arg registers. */
ldp x2, x3, [x0, oX0 + 2 * SZREG]
ldp x4, x5, [x0, oX0 + 4 * SZREG]
ldp x6, x7, [x0, oX0 + 6 * SZREG]
ldp x0, x1, [x0, oX0 + 0 * SZREG]
/* Jump to the new pc value. */
br x16
PSEUDO_END (__setcontext)
weak_alias (__setcontext, setcontext)
ENTRY (__startcontext)
mov x0, x19
cbnz x0, __setcontext
1: b HIDDEN_JUMPTARGET (_exit)
END (__startcontext)
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