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/* { dg-do link } */
/* { dg-options "--param allow-store-data-races=0 -O2" } */
/* { dg-final { simulate-thread } } */
#include <stdio.h>
#include <stdlib.h>
#include "simulate-thread.h"
/* Test distilled from PR52558. */
int g_1 = 1;
int g_2 = 0, insns = 0;
int f;
/* Test that g_2 is not written to unless !g_1. */
__attribute__((noinline))
int funky()
{
int l;
for (l = 0; l != 4; l++)
{
if (g_1)
{
/* g_1 is globally true so we should always execute here,
thus never writing to g_2 under any circumstance in this
code path. */
return l;
}
for (g_2 = 0; g_2 >= 26; ++g_2)
;
}
return 999;
}
int simulate_thread_final_verify ()
{
/* If g_2 != insns, someone must have cached `g_2' and stored a
racy value into it. */
if (g_2 != insns)
{
printf("FAIL: g_2 was incorrectly cached\n");
return 1;
}
return 0;
}
void simulate_thread_other_threads ()
{
++insns;
++g_2;
}
int simulate_thread_step_verify ()
{
return 0;
}
__attribute__((noinline))
void simulate_thread_main()
{
f = funky();
}
int main()
{
simulate_thread_main ();
simulate_thread_done ();
return 0;
}
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