C++: data flow AlwaysTrueUponEntryLoop perf fix #598
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The predicate `AlwaysTrueUponEntryLoop.getARelevantVariable` was very sensitive to join ordering, and with the 1.19 QL engine it got an unfortunate join order that made it explode on certain snapshots. With this change, it goes from taking minutes to taking less than a second on a libretro-uae snapshot.
cklin
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May 23, 2022
Fixed broken/moved/redirected links.
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The predicate
AlwaysTrueUponEntryLoop.getARelevantVariablewas very sensitive to join ordering, and with the 1.19 QL engine it got an unfortunate join order that made it explode on certain snapshots. With this change, it goes from taking minutes to taking less than a second on a libretro-uae snapshot.This should fix the problem noticed by @geoffw0 in #403. Please test.