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authorWaldemar Brodkorb <wbx@openadk.org>2015-02-14 23:04:02 -0600
committerWaldemar Brodkorb <wbx@openadk.org>2015-02-14 23:04:02 -0600
commite1e46622ac0fce73d802fa4a8a2e83cc25cd9e7a (patch)
tree2c8d14e4dcc733f4227f0984ed05da5826b13acd /libpthread/linuxthreads/sysdeps/i386/i686/pt-machine.h
parent6b6ede3d15f04fe825cfa9f697507457e3640344 (diff)
Revert "resolve merge"
This reverts commit 6b6ede3d15f04fe825cfa9f697507457e3640344.
Diffstat (limited to 'libpthread/linuxthreads/sysdeps/i386/i686/pt-machine.h')
-rw-r--r--libpthread/linuxthreads/sysdeps/i386/i686/pt-machine.h78
1 files changed, 78 insertions, 0 deletions
diff --git a/libpthread/linuxthreads/sysdeps/i386/i686/pt-machine.h b/libpthread/linuxthreads/sysdeps/i386/i686/pt-machine.h
new file mode 100644
index 000000000..2e52abe2e
--- /dev/null
+++ b/libpthread/linuxthreads/sysdeps/i386/i686/pt-machine.h
@@ -0,0 +1,78 @@
+/* Machine-dependent pthreads configuration and inline functions.
+ i686 version.
+ Copyright (C) 1996-2001, 2002, 2003 Free Software Foundation, Inc.
+ This file is part of the GNU C Library.
+ Contributed by Richard Henderson <rth@tamu.edu>.
+
+ 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; see the file COPYING.LIB. If
+ not, see <http://www.gnu.org/licenses/>. */
+
+#ifndef _PT_MACHINE_H
+#define _PT_MACHINE_H 1
+
+#ifndef PT_EI
+# define PT_EI __extern_always_inline
+#endif
+#include <bits/kernel-features.h>
+
+#ifndef __ASSEMBLER__
+extern long int testandset (int *spinlock);
+extern int __compare_and_swap (long int *p, long int oldval, long int newval);
+
+/* Get some notion of the current stack. Need not be exactly the top
+ of the stack, just something somewhere in the current frame. */
+#define CURRENT_STACK_FRAME __builtin_frame_address (0)
+
+
+/* Spinlock implementation; required. */
+PT_EI long int
+testandset (int *spinlock)
+{
+ long int ret;
+
+ __asm__ __volatile__ (
+ "xchgl %0, %1"
+ : "=r" (ret), "=m" (*spinlock)
+ : "0" (1), "m" (*spinlock)
+ : "memory");
+
+ return ret;
+}
+
+
+/* Compare-and-swap for semaphores. It's always available on i686. */
+#define HAS_COMPARE_AND_SWAP
+
+PT_EI int
+__compare_and_swap (long int *p, long int oldval, long int newval)
+{
+ char ret;
+ long int readval;
+
+ __asm__ __volatile__ ("lock; cmpxchgl %3, %1; sete %0"
+ : "=q" (ret), "=m" (*p), "=a" (readval)
+ : "r" (newval), "m" (*p), "a" (oldval)
+ : "memory");
+ return ret;
+}
+#endif
+
+#if __ASSUME_LDT_WORKS > 0
+#include "../useldt.h"
+#endif
+
+/* The P4 and above really want some help to prevent overheating. */
+#define BUSY_WAIT_NOP __asm__ ("rep; nop")
+
+#endif /* pt-machine.h */