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Possible missed optimization for non-common bidirectional ranges in <algorithm> #5903

Description

This issue is an extension of #5886 (and the corresponding PR #5887), as it appears that there are other locations where _Bidi_common<_It, _Se> is checked, where I believe the less strict bidirectional_iterator<_It> would suffice.

In the following cases, for a non-common range with bidirectional iterators, the search runs from the beginning instead of from the end, resulting in more applications of projection and predicate than necessary.

_Find_last_unchecked

if constexpr (_Bidi_common<_It, _Se>) {

_Find_last_if_unchecked

if constexpr (_Bidi_common<_It, _Se>) {

However I have not checked all references to _Bidi_common (e.g. in _Shift_right_impl), so there could be more.

Note that _Partition_unchecked is already covered by #5886

if constexpr (_Bidi_common<_It, _Se>) {

I can look into it, but I would like someone with more experience to first confirm that I have not come to an incorrect conclusion.

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