[4/5] Sanitize irange::num_pairs
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Commit Message
irange::num_pairs has odd behavior for VR_ANTI_RANGE where it
claims there are two pairs when there's actually only one. The
following is now able to get rid of this, also fixing
irange::legacy_upper_bound which special-cased ~[-INF, up]
to return +INF instead of properly doing that when up is not +INF.
* value-range.h (irange::num_pairs): Always return
m_num_ranges.
* value-range.cc (irange::legacy_lower_bound): Remove
pair == 1 case.
(irange::legacy_upper_bound): Likewise. Properly
special-case ~[low, +INF].
---
gcc/value-range.cc | 6 ++++--
gcc/value-range.h | 5 +----
2 files changed, 5 insertions(+), 6 deletions(-)
Comments
I would prefer not touching this as it was intended, and about to be
removed. However, if we have actual regressions or missed optimizations
because of the current behavior I could be convinced otherwise.
Aldy
On 2/28/23 14:47, Richard Biener via Gcc-patches wrote:
> irange::num_pairs has odd behavior for VR_ANTI_RANGE where it
> claims there are two pairs when there's actually only one. The
> following is now able to get rid of this, also fixing
> irange::legacy_upper_bound which special-cased ~[-INF, up]
> to return +INF instead of properly doing that when up is not +INF.
>
> * value-range.h (irange::num_pairs): Always return
> m_num_ranges.
> * value-range.cc (irange::legacy_lower_bound): Remove
> pair == 1 case.
> (irange::legacy_upper_bound): Likewise. Properly
> special-case ~[low, +INF].
> ---
> gcc/value-range.cc | 6 ++++--
> gcc/value-range.h | 5 +----
> 2 files changed, 5 insertions(+), 6 deletions(-)
>
> diff --git a/gcc/value-range.cc b/gcc/value-range.cc
> index a535337c47a..143af5601c7 100644
> --- a/gcc/value-range.cc
> +++ b/gcc/value-range.cc
> @@ -1208,7 +1208,8 @@ irange::legacy_lower_bound (unsigned pair) const
> if (m_kind == VR_ANTI_RANGE)
> {
> tree typ = type (), t;
> - if (pair == 1 || vrp_val_is_min (min ()))
> + gcc_checking_assert (pair == 0);
> + if (vrp_val_is_min (min ()))
> t = wide_int_to_tree (typ, wi::to_wide (max ()) + 1);
> else
> t = vrp_val_min (typ);
> @@ -1235,7 +1236,8 @@ irange::legacy_upper_bound (unsigned pair) const
> if (m_kind == VR_ANTI_RANGE)
> {
> tree typ = type (), t;
> - if (pair == 1 || vrp_val_is_min (min ()))
> + gcc_checking_assert (pair == 0);
> + if (!vrp_val_is_max (max ()))
> t = vrp_val_max (typ);
> else
> t = wide_int_to_tree (typ, wi::to_wide (min ()) - 1);
> diff --git a/gcc/value-range.h b/gcc/value-range.h
> index f4ac73b499f..cfb51bad915 100644
> --- a/gcc/value-range.h
> +++ b/gcc/value-range.h
> @@ -614,10 +614,7 @@ vrange::kind () const
> inline unsigned
> irange::num_pairs () const
> {
> - if (m_kind == VR_ANTI_RANGE)
> - return constant_p () ? 2 : 1;
> - else
> - return m_num_ranges;
> + return m_num_ranges;
> }
>
> inline tree
@@ -1208,7 +1208,8 @@ irange::legacy_lower_bound (unsigned pair) const
if (m_kind == VR_ANTI_RANGE)
{
tree typ = type (), t;
- if (pair == 1 || vrp_val_is_min (min ()))
+ gcc_checking_assert (pair == 0);
+ if (vrp_val_is_min (min ()))
t = wide_int_to_tree (typ, wi::to_wide (max ()) + 1);
else
t = vrp_val_min (typ);
@@ -1235,7 +1236,8 @@ irange::legacy_upper_bound (unsigned pair) const
if (m_kind == VR_ANTI_RANGE)
{
tree typ = type (), t;
- if (pair == 1 || vrp_val_is_min (min ()))
+ gcc_checking_assert (pair == 0);
+ if (!vrp_val_is_max (max ()))
t = vrp_val_max (typ);
else
t = wide_int_to_tree (typ, wi::to_wide (min ()) - 1);
@@ -614,10 +614,7 @@ vrange::kind () const
inline unsigned
irange::num_pairs () const
{
- if (m_kind == VR_ANTI_RANGE)
- return constant_p () ? 2 : 1;
- else
- return m_num_ranges;
+ return m_num_ranges;
}
inline tree