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/*
* Licensed under the LGPL v2.1 or later, see the file COPYING.LIB in this tarball.
*/
#ifndef _PT_MACHINE_H
#define _PT_MACHINE_H 1
#include <features.h>
#ifndef PT_EI
# define PT_EI __extern_always_inline
#endif
#define HAS_COMPARE_AND_SWAP
PT_EI int
__compare_and_swap (long int *p, long int oldval, long int newval)
{
long int ret, temp;
__asm__ __volatile__
("/* Inline compare & swap */\n"
"1:\n\t"
"lr.w %1,%2\n\t"
"li %0,0\n\t"
"bne %1,%3,2f\n\t"
"li %0,1\n\t"
"sc.w %1,%4,%2\n\t"
"bnez %1,1b\n"
"2:\n\t"
"/* End compare & swap */"
: "=&r" (ret), "=&r" (temp), "+A" (*p)
: "r" (oldval), "r" (newval)
: "memory");
return ret;
}
extern long int testandset (int *spinlock);
PT_EI long int
testandset (int *spinlock)
{
unsigned int old = 1;
int tmp = 1;
__asm__ __volatile__ (
"amoswap.w %0, %2, %1"
: "=r" (old), "+A" (*spinlock)
: "r" (tmp)
: "memory");
return old;
}
/* 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 stack_pointer
register char * stack_pointer __asm__ ("sp");
#else
#error PT_MACHINE already defined
#endif /* pt-machine.h */
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