[simplify-cfg] When moving cond_fail to preds, do not bail early. #3569
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@swift-ci Please smoke test and merge |
This commit fixes a bug where we were not checking that all predecessors had the cond_fail block as its only successor. This occured since we were bailing early when we saw a constant. So if we saw a predecessor with a constant before a predecessor that had multiple successors, we would optimize even though we would be introducing an extra cond_fail along a path. I added a new utility pass to test this code since so much is going on in SimplifyCFG that it is difficult to construct a test case running the full pass. Really this code should be in a different pass (properly SIL Code Motion TBH). But for now, this commit just fixes the bug. rdar://26904047
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@swift-ci Please smoke test and merge |
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What's in this pull request?
Resolved bug number: (SR-)
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This commit fixes a bug where we were not checking that all predecessors had the
cond_fail block as its only successor. This occured since we were bailing early
when we saw a constant. So if we saw a predecessor with a constant before a
predecessor that had multiple successors, we would optimize even though we would
be introducing an extra cond_fail along a path.
I added a new utility pass to test this code since so much is going on in
SimplifyCFG that it is difficult to construct a test case running the full
pass.
Really this code should be in a different pass (properly SIL Code Motion TBH).
But for now, this commit just fixes the bug.
rdar://26904047