tsx test

hle_test.c

#include <stdlib.h>
#include <stdio.h>

/* note: much of tsx code was stolen from glibc */

/* Official RTM intrinsics interface matching gcc/icc, but works
   on older gcc compatible compilers and binutils.
   We should somehow detect if the compiler supports it, because
   it may be able to generate slightly better code. */

#define _XABORT_EXPLICIT       (1 << 0)
#define _XABORT_RETRY          (1 << 1)
#define _XABORT_CONFLICT       (1 << 2)
#define _XABORT_CAPACITY       (1 << 3)
#define _XABORT_DEBUG          (1 << 4)
#define _XABORT_NESTED         (1 << 5)
#define _XABORT_CODE(x)                (((x) >> 24) & 0xff)

#define _XBEGIN_STARTED                (~0u)

#define _ABORT_LOCK_BUSY       0xff
#define _ABORT_LOCK_IS_LOCKED  0xfe
#define _ABORT_NESTED_TRYLOCK  0xfd

#define __force_inline __attribute__((__always_inline__)) inline



#ifdef USE_TSX

static __force_inline int _xbegin(void)
{
  int ret = _XBEGIN_STARTED;
  asm volatile (".byte 0xc7,0xf8 ; .long 0" : "+a" (ret) :: "memory");
  return ret;
}

static __force_inline void _xend(void)
{
  asm volatile (".byte 0x0f,0x01,0xd5" ::: "memory");
}

static __force_inline void _xabort(const unsigned int status)
{
  asm volatile (".byte 0xc6,0xf8,%P0" :: "i" (status) : "memory");
}

static __force_inline int _xtest(void)
{
  unsigned char out;
  asm volatile (".byte 0x0f,0x01,0xd6 ; setnz %0" : "=r" (out) :: "memory");
  return out;
}

#else

static __force_inline int _xbegin(void)
{
  int ret = _XBEGIN_STARTED;
  return ret;
}

static __force_inline void _xend(void)
{
}

static __force_inline void _xabort(const unsigned int status)
{
	abort();
}

static volatile xtest_thing;

static __force_inline int _xtest(void)
{
	return !xtest_thing;
}

#endif



static volatile int some_location __attribute__((aligned(64)));

static volatile unsigned long long some_other_location __attribute__((aligned(64)));

static volatile unsigned int skips __attribute__((aligned(64)));

int main(void)
{
	unsigned int i;
	unsigned int initial = (unsigned)(0x20000000);
	for (i = initial; i>0; i--) {
		int status;
	again:
		status = _xbegin();
		/* 
                 * if (status != _XBEGIN_STARTED) {
		 * 	skips++;
		 * 	goto again;
		 * }
                 */
		if (!_xtest()) {
			skips++;
			if (skips == (unsigned)0xffff) {
				abort();
			}
			goto again;
		}
		if (status != _XBEGIN_STARTED) {
			_xabort(_ABORT_LOCK_BUSY);
		}
		if (some_location != 0)
			_xabort(_ABORT_LOCK_IS_LOCKED);

#ifdef USE_TSX
		some_other_location++;
#else
		{
			unsigned long long new_value = some_other_location + 1;
			if (!__sync_bool_compare_and_swap(&some_other_location, new_value - 1, new_value)) {
				abort();
			}
		}
#endif
		_xend();
	}

	printf("skips: %u, total txns: %u\n", skips, initial);
	return 0;
}