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-rw-r--r--libpthread/linuxthreads/sysdeps/xtensa/pt-machine.h79
1 files changed, 79 insertions, 0 deletions
diff --git a/libpthread/linuxthreads/sysdeps/xtensa/pt-machine.h b/libpthread/linuxthreads/sysdeps/xtensa/pt-machine.h
new file mode 100644
index 000000000..2c68ddfb5
--- /dev/null
+++ b/libpthread/linuxthreads/sysdeps/xtensa/pt-machine.h
@@ -0,0 +1,79 @@
+/* Machine-dependent pthreads configuration and inline functions.
+ Xtensa version.
+
+ Copyright (C) 2007 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/>. */
+
+#ifndef _PT_MACHINE_H
+#define _PT_MACHINE_H 1
+
+#include <sys/syscall.h>
+#include <asm/unistd.h>
+
+#ifndef PT_EI
+# define PT_EI extern inline __attribute__ ((gnu_inline))
+#endif
+
+#define MEMORY_BARRIER() __asm__ ("memw" : : : "memory")
+#define HAS_COMPARE_AND_SWAP
+
+extern long int testandset (int *spinlock);
+extern int __compare_and_swap (long int *p, long int oldval, long int newval);
+
+/* Spinlock implementation; required. */
+PT_EI long int
+testandset (int *spinlock)
+{
+ unsigned long tmp;
+ __asm__ volatile (
+" movi %0, 0 \n"
+" wsr %0, SCOMPARE1 \n"
+" movi %0, 1 \n"
+" s32c1i %0, %1, 0 \n"
+ : "=&a" (tmp)
+ : "a" (spinlock)
+ : "memory"
+ );
+ return tmp;
+}
+
+PT_EI int
+__compare_and_swap (long int *p, long int oldval, long int newval)
+{
+ unsigned long tmp;
+ unsigned long value;
+ __asm__ volatile (
+"1: l32i %0, %2, 0 \n"
+" bne %0, %4, 2f \n"
+" wsr %0, SCOMPARE1 \n"
+" mov %1, %0 \n"
+" mov %0, %3 \n"
+" s32c1i %0, %2, 0 \n"
+" bne %1, %0, 1b \n"
+"2: \n"
+ : "=&a" (tmp), "=&a" (value)
+ : "a" (p), "a" (newval), "a" (oldval)
+ : "memory" );
+
+ return tmp == oldval;
+}
+
+/* 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)
+
+#endif /* _PT_MACHINE_H */