1 /* Test proper lookup-uncaching of large objects */
2 #include "../config.h"
3 
4 #include <unistd.h>
5 #include <string.h>
6 #include <stdio.h>
7 #include <stdlib.h>
8 #ifdef HAVE_SYS_MMAN_H
9 #include <sys/mman.h>
10 #endif
11 
12 int main ()
13 {
14 #ifndef MAP_ANONYMOUS
15 #define MAP_ANONYMOUS MAP_ANON
16 #endif
17 #ifdef HAVE_MMAP
18   volatile unsigned char *p;
19   unsigned num = getpagesize ();
20   unsigned i;
21   int rc;
22 
23   /* Get a bit of usable address space.  We really want an 2**N+1-sized object,
24      so the low/high addresses wrap when hashed into the lookup cache.  So we
25      will manually unregister the entire mmap, then re-register a slice.  */
26   p = mmap (NULL, num, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, 0, 0);
27   if (p == NULL)
28     return 1;
29   /* Now unregister it, as if munmap was called.  But don't actually munmap, so
30      we can write into the memory.  */
31   __mf_unregister ((void *) p, num, __MF_TYPE_HEAP_I);
32 
33   /* Now register it under a slightly inflated, 2**N+1 size.  */
34   __mf_register ((void *) p, num+1, __MF_TYPE_HEAP_I, "fake mmap registration");
35 
36   /* Traverse array to ensure that entire lookup cache is made to point at it.  */
37   for (i=0; i<num; i++)
38     p[i] = 0;
39 
40   /* Unregister it.  This should clear the entire lookup cache, even though
41      hash(low) == hash (high)  (and probably == 0) */
42   __mf_unregister ((void *) p, num+1, __MF_TYPE_HEAP_I);
43 
44   /* Now touch the middle portion of the ex-array.  If the lookup cache was
45      well and truly cleaned, then this access should trap.  */
46   p[num/2] = 1;
47 
48   return 0;
49 #else
50   return 1;
51 #endif
52 }
53 /* { dg-output "mudflap violation 1.*check/write.*" } */
54 /* { dg-output "Nearby object 1.*" } */
55 /* { dg-output "mudflap dead object.*fake mmap registration.*" } */
56 /* { dg-do run { xfail *-*-* } } */
57