Commit Graph

3 Commits

Author SHA1 Message Date
Nikita Popov fb063c933f [InstCombine] Duplicate tests for logical and/or (NFC)
This replicates existing and/or tests to also test variants using
select. This should help us get a more accurate view on which
optimizations we're missing if we disable the select -> and/or
fold.
2021-01-12 21:50:41 +01:00
Florian Hahn 14ef87bda6 [ValueTracking] usub(a, b) cannot overflow if a >= b.
If we know that a >= b (unsigned), usub.with.overflow(a, b) cannot
overflow. Similarly, if b > a, the same expression overflows.

Reviewers: nikic, RKSimon, lebedev.ri, spatel

Reviewed By: nikic, Gerolf

Differential Revision: https://reviews.llvm.org/D74066
2020-02-07 10:41:18 +00:00
Florian Hahn 89ca4b9ef2 [InstCombine] Precommit usub.with.overflow test for D74066. 2020-02-07 10:30:28 +00:00