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/* Copyright (C) 1993-2023 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 <features.h>
#if defined(PIC)
/* Put this at the end of libc's text segment so that all of
the direct branches from the syscalls are forward, and
thus predicted not taken. */
.section .text.last, "ax", @progbits
#else
.text
#endif
#if IS_IN (libc)
# define SYSCALL_ERROR_ERRNO __libc_errno
#else
# define SYSCALL_ERROR_ERRNO errno
#endif
.align 4
.globl __syscall_error
.ent __syscall_error
__syscall_error:
/* When building a shared library, we branch here without having
loaded the GP. Nor, since it was a direct branch, have we
loaded PV with our address.
When building a static library, we tail call here from another
object file, possibly with a different GP, and must return with
the GP of our caller in place so that linker relaxation works.
Both issues are solved by computing the GP into T1 instead of
clobbering the traditional GP register. */
.prologue 0
mov v0, t0
br t1, 1f
1: ldah t1, 0(t1) !gpdisp!1
call_pal PAL_rduniq
lda t1, 0(t1) !gpdisp!1
ldq t1, SYSCALL_ERROR_ERRNO(t1) !gottprel
addq v0, t1, t1
lda v0, -1
stl t0, 0(t1)
ret
.end __syscall_error
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