[Bug tree-optimization/104356] [12 Regression] divide by zero trap is being removed now when it should not be in some cases

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104356

--- Comment #16 from Richard Biener <rguenth at gcc dot gnu.org> ---
Related simplifications:

 /* X / bool_range_Y is X.  */
 (simplify
  (div @0 SSA_NAME@1)
  (if (INTEGRAL_TYPE_P (type) && ssa_name_has_boolean_range (@1))
   @0))

 /* X / abs (X) is X < 0 ? -1 : 1.  */
 (simplify
   (div:C @0 (abs @0))
   (if (INTEGRAL_TYPE_P (type)
        && TYPE_OVERFLOW_UNDEFINED (type))
    (cond (lt @0 { build_zero_cst (type); })
          { build_minus_one_cst (type); } { build_one_cst (type); })))

 /* X / -X is -1.  */
 (simplify
   (div:C @0 (negate @0))
   (if ((INTEGRAL_TYPE_P (type) || VECTOR_INTEGER_TYPE_P (type))
        && TYPE_OVERFLOW_UNDEFINED (type))
    { build_minus_one_cst (type); })))