bdb9430917
Summary: We are incorrectly updating the LI when loop-simplify generates dedicated exit blocks for a loop. The issue is that there's an implicit assumption that the Preds passed into UpdateAnalysisInformation are reachable. However, this is not true and breaks LI by incorrectly updating the header of a loop. One such case is when we generate dedicated exits when the exit block is a landing pad (through SplitLandingPadPredecessors). There maybe other cases as well, since we do not guarantee that Preds passed in are reachable basic blocks. The added test case shows how loop-simplify breaks LI for the outer loop (and DT in turn) after we try to generate the LoopSimplifyForm. Reviewers: davide, chandlerc, sanjoy Reviewed By: davide Subscribers: llvm-commits Differential Revision: https://reviews.llvm.org/D41519 llvm-svn: 321653 |
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| .. | ||
| 2003-04-25-AssertFail.ll | ||
| 2003-05-12-PreheaderExitOfChild.ll | ||
| 2003-08-15-PreheadersFail.ll | ||
| 2003-12-10-ExitBlocksProblem.ll | ||
| 2004-02-05-DominatorInfoCorruption.ll | ||
| 2004-03-15-IncorrectDomUpdate.ll | ||
| 2004-04-01-IncorrectDomUpdate.ll | ||
| 2004-04-12-LoopSimplify-SwitchBackedges.ll | ||
| 2004-04-13-LoopSimplifyUpdateDomFrontier.ll | ||
| 2007-10-28-InvokeCrash.ll | ||
| 2010-07-15-IncorrectDomFrontierUpdate.ll | ||
| 2010-12-26-PHIInfiniteLoop.ll | ||
| 2011-12-14-LandingpadHeader.ll | ||
| 2012-03-20-indirectbr.ll | ||
| ashr-crash.ll | ||
| basictest.ll | ||
| dbg-loc.ll | ||
| dup-preds.ll | ||
| hardertest.ll | ||
| indirectbr-backedge.ll | ||
| indirectbr.ll | ||
| merge-exits.ll | ||
| notify-scev.ll | ||
| phi-node-simplify.ll | ||
| pr26682.ll | ||
| pr28272.ll | ||
| pr30454.ll | ||
| pr33494.ll | ||
| preserve-llvm-loop-metadata.ll | ||
| preserve-scev.ll | ||
| single-backedge.ll | ||
| unreachable-loop-pred.ll | ||