[Bug sanitizer/102515] UBSAN misses signed division instrumentation

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102515

--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #5)
> Created attachment 51529 [details]
> gcc12-pr102515.patch
> 
> I have one too, even bootstrapped/regtested overnight, just didn't get to
> writing new testcases that would cover the cases that need testing (i.e. that
> -f{,no-}sanitize-recover=float-divide-by-zero rather than
> -f{,no-}sanitize-recover=integer-divide-by-zero decides on *_abort for float
> division and the behavior for -fsanitize=undefined
> -fno-sanitize-recover=integer-divide-by-zero or -fsanitize=undefined
> -fno-sanitize-recover=signed-integer-overflow (i.e. when
> integer-divide-by-zero and signed-integer-overflow differ in the recover
> method).

OK, so yours looks mostly identical to mine, even handling one minor case
better and erring on the side to not preserve divide overflow with
divide-by-zero (which I think is reasonable).

I've yet only added c-c++-common/ubsan/overflow-div-1.c as

/* { dg-do run } */
/* { dg-options "-fsanitize=signed-integer-overflow" } */
/* { dg-shouldfail "ubsan" } */

int __attribute__((noipa))
foo (int a, int b)
{
  return a / b;
}

int
main ()
{
  return foo (-__INT_MAX__ - 1, -1);
}

/* { dg-output "cannot be represented" } */

and did not add testcases for the fixed float-divide recovery (which I also
noticed and fixed).

Note I simply track whether _all_ of the used instrumentations have
recovery enabled and if not then go the abort path.