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/* PR tree-optimization/83047 */
/* { dg-do run { target mmap } } */
/* { dg-options "-O2" } */
#include <stddef.h>
#include <stdio.h>
#include <sys/mman.h>
#ifndef MAP_ANONYMOUS
#define MAP_ANONYMOUS MAP_ANON
#endif
#ifndef MAP_ANON
#define MAP_ANON 0
#endif
#ifndef MAP_FAILED
#define MAP_FAILED ((void *)-1)
#endif
#include <stdlib.h>
__attribute__((noipa)) void
foo (char *p, char *q, int r)
{
char a = q[0];
if (r || a == '\0')
return;
char b = q[1];
p[0] = a;
p[1] = b;
}
int
main ()
{
char *p = mmap (NULL, 131072, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (p == MAP_FAILED)
return 0;
if (munmap (p + 65536, 65536) < 0)
return 0;
p[0] = 'c';
p[1] = 'd';
p[65536 - 2] = 'a';
p[65536 - 1] = 'b';
volatile int r = 1;
foo (p, p + 65536 - 2, r);
if (p[0] != 'c' || p[1] != 'd')
abort ();
r = 0;
foo (p, p + 65536 - 2, r);
if (p[0] != 'a' || p[1] != 'b')
abort ();
p[0] = 'e';
p[1] = 'f';
r = 1;
foo (p, p + 65536 - 1, r);
if (p[0] != 'e' || p[1] != 'f')
abort ();
return 0;
}
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