On 3/10/23 09:53, Richard Biener wrote:
On Fri, 10 Mar 2023, Jakub Jelinek wrote:
Coming back to this...
/* Temporarily disable -ffinite-math-only, so that frange::set doesn't
reduce the range back to real_min_representable (type) as lower bound
or real_max_representable (type) as upper bound. */
bool save_flag_finite_math_only = flag_finite_math_only;
flag_finite_math_only = false;
ret.set (type, lb, ub);
if (lhs.kind () != VR_VARYING)
{
ret.clear_nan ();
ret.union_ (lhs);
}
flag_finite_math_only = save_flag_finite_math_only;
It looks like what you want to do is be able to create a range with a
known NAN state, but without the setter reducing the range to
min/max_representable.
How about we enhance the API to provide:
1. Constructor with a known NAN state.
2. Setter with a flag to keep it from canonicalizing into
min/max_representable.
The flag in 2 could in the future be saved in the frange object to keep
union and friends from further canonicalization.
So the above could be written as:
// Construct [lb, ub] with a known NAN state.
frange tmp (lb, ub, lhs.get_nan_state ());
// Set RET without dropping/reducing the range to MIN/MAX.
ret.set (tmp, FRANGE_FLAG_NO_REPRESENTABLE_REDUCTION);
An alternative is to allow the setter to set everything:
ret.set (type, lb, ub,
lhs.get_nan_state (),
FRANGE_FLAG_NO_REPRESENTABLE_REDUCTION);
Would this work? I'd be happy to whip up something this week, or if
preferred, leave it to the next release.
Aldy
