47 lines
1.2 KiB
C
47 lines
1.2 KiB
C
/* Test whether strncmp has not been "optimized" into memcmp
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nor any code with memcmp semantics. */
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/* { dg-do run { target i?86-*-linux* x86_64-*-linux* ia64-*-linux* alpha*-*-linux* powerpc*-*-linux* s390*-*-linux* sparc*-*-linux* *-*-darwin* } } */
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/* { dg-options "-O2" } */
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#include <stddef.h>
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#include <stdio.h>
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#include <sys/mman.h>
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/* Darwin spells this differently */
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#ifndef MAP_ANONYMOUS
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#define MAP_ANONYMOUS MAP_ANON
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#endif
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#include <stdlib.h>
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struct Flags {
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int filler[18];
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unsigned int a:14;
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unsigned int b:14;
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unsigned int c:1;
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unsigned int d:1;
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unsigned int e:1;
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unsigned int f:1;
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};
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static void __attribute__((noinline)) set (struct Flags *);
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static void set (struct Flags *fp)
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{
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fp->b = 5;
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fp->d = 1;
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}
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static int __attribute__((noinline)) bar (int);
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static int bar(int x) { return !(x==1); }
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int main (void)
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{
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char *p = mmap (NULL, 131072, PROT_READ | PROT_WRITE,
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MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
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struct Flags *fp;
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if (p == MAP_FAILED)
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return 0;
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if (munmap (p + 65536, 65536) < 0)
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return 0;
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fp = (struct Flags*)(p + 65536 - sizeof(struct Flags));
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set(fp);
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if (fp->b > 0)
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return (bar(fp->d));
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return 1;
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}
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