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Diffstat (limited to 'sysdeps/unix/sysv/linux/x86_64/sem_trywait.S')
-rw-r--r--sysdeps/unix/sysv/linux/x86_64/sem_trywait.S47
1 files changed, 47 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/x86_64/sem_trywait.S b/sysdeps/unix/sysv/linux/x86_64/sem_trywait.S
new file mode 100644
index 0000000000..1893a34737
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/x86_64/sem_trywait.S
@@ -0,0 +1,47 @@
+/* Copyright (C) 2002-2014 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
+
+ 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 <lowlevellock.h>
+#include <shlib-compat.h>
+#include <pthread-errnos.h>
+
+ .text
+
+ .globl sem_trywait
+ .type sem_trywait,@function
+ .align 16
+sem_trywait:
+ movl (%rdi), %eax
+2: testl %eax, %eax
+ jz 1f
+
+ leal -1(%rax), %edx
+ LOCK
+ cmpxchgl %edx, (%rdi)
+ jne 2b
+
+ xorl %eax, %eax
+ retq
+
+1:
+ movq errno@gottpoff(%rip), %rdx
+ movl $EAGAIN, %fs:(%rdx)
+ orl $-1, %eax
+ retq
+ .size sem_trywait,.-sem_trywait