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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 that speculative stores do not happen for --param
allow-store-data-races=0. */
int count, insns;
struct obj {
int data;
struct obj *next;
} *q;
void simulate_thread_other_threads ()
{
++insns;
++count;
}
int simulate_thread_step_verify ()
{
return 0;
}
int simulate_thread_final_verify ()
{
/* If count != insns, someone must have cached `count' and stored a
racy value into it. */
if (count != insns)
{
printf("FAIL: count was incorrectly cached\n");
return 1;
}
return 0;
}
/* Test that `count' is not written to unless p->data > 0. */
__attribute__((noinline))
void simulate_thread_main()
{
struct obj *p;
for (p = q; p; p = p->next)
if (p->data > 0)
count++;
}
struct obj *
insert(struct obj *head, int data)
{
struct obj *t = (struct obj *) malloc (sizeof (struct obj));
t->next = head;
t->data = data;
return t;
}
int main()
{
q = insert (0, 0);
q = insert (q, 0);
q = insert (q, 0);
q = insert (q, 0);
q = insert (q, 0);
simulate_thread_main ();
simulate_thread_done ();
return 0;
}
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