DeadCodeElimination,SILCombine: don't insert destroys for removed values in dead-end blocks #85855
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eeckstein
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If followed by a dead infinite loop, the array initialization might have beed removed. Therefore when inserting a compensating destroy of the array buffer can lead to a crash. swiftlang#85851 rdar://165876726
…-end blocks When an owned value has no lifetime ending uses it means that it is in a dead-end region. We must not remove and inserting compensating destroys for it because that would potentially destroy the value too early. Initialization of an object might be cut off and removed after a dead-end loop or an `unreachable`. In this case a class destructor would see uninitialized fields. Fixes a mis-compile swiftlang#85851 rdar://165876726
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When an owned value has no lifetime ending uses it means that it is in a dead-end region.
We must not remove and inserting compensating destroys for it because that would potentially destroy the value too early.
Initialization of an object might be cut off and removed after a dead-end loop or an
unreachable.In this case a class destructor would see uninitialized fields.
Also fix the same problem in SILCombine for dead
Array.adoptStoragecalls.Fixes a mis-compile
#85851
rdar://165876726