On Fri, May 27, 2022 at 9:34 PM Andi Kleen via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> Andrew MacLeod via Gcc-patches <gcc-patches@gcc.gnu.org> writes:
> >
> > diff --git a/gcc/gimple-range-side-effect.cc
> > b/gcc/gimple-range-side-effect.cc
> > index 2c8c77dc569..548e4bea313 100644
> > --- a/gcc/gimple-range-side-effect.cc
> > +++ b/gcc/gimple-range-side-effect.cc
> > @@ -116,6 +116,23 @@ stmt_side_effects::stmt_side_effects (gimple *s)
> > walk_stmt_load_store_ops (s, (void *)this, non_null_loadstore,
> > non_null_loadstore);
> >
> > + if (is_a<gassign *> (s))
> > + {
> > + switch (gimple_assign_rhs_code (s))
> > + {
> > + case TRUNC_DIV_EXPR:
> > + case CEIL_DIV_EXPR:
> > + case FLOOR_DIV_EXPR:
> > + case ROUND_DIV_EXPR:
> > + case EXACT_DIV_EXPR:
> > + // Divide means operand 2 is not zero after this stmt.
> > + if (gimple_range_ssa_p (gimple_assign_rhs2 (s)))
> > + add_nonzero (gimple_assign_rhs2 (s));
>
> Sorry I'm late, but how does this ensure the value is a integer?
> I believe for floating point the assumption is not correct because
> division by zero doesn't necessarily fault.
non-integer divisions use a different TREE_CODE (RDIV_EXPR).
>
> -Andi
