[Bug tree-optimization/113588] [14 Regression] The vectorizer is introducing out-of-bounds memory access

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113588

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |14.0
   Last reconfirmed|                            |2024-01-24
            Summary|The vectorizer is           |[14 Regression] The
                   |introducing out-of-bounds   |vectorizer is introducing
                   |memory access               |out-of-bounds memory access
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Confirmed, runable testcase:
```
#include <sys/mman.h>
#include <unistd.h>

__attribute__((noipa))
int foo (const char *s, unsigned long n)
{
 unsigned long len = 0;
 while (*s++ && n--)
   ++len;
 return len;
}

int main()
{
  long pgsz = sysconf (_SC_PAGESIZE);
  void *p = mmap (NULL, pgsz * 3, PROT_READ|PROT_WRITE,
     MAP_ANONYMOUS|MAP_PRIVATE, 0, 0);
  if (p == MAP_FAILED)
    return 0;
  mprotect (p, pgsz, PROT_NONE);
  mprotect (p+2*pgsz, pgsz, PROT_NONE);
  char *p1 = p + pgsz;
  p1[0] = 1;
  p1[1] = 0;
  foo (p1, 1000);
  p1 = p + 2*pgsz - 2;
  p1[0] = 1;
  p1[1] = 0;
  foo (p1, 1000);
  return 0;
}
```