Chijun Sima 586187639a Make MergeBlockIntoPredecessor conformant to the precondition of calling DTU.applyUpdates ...

Summary:
It is mentioned in the document of DTU that "It is illegal to submit any update that has already been submitted, i.e., you are supposed not to insert an existent edge or delete a nonexistent edge." It is dangerous to violet this rule because DomTree and PostDomTree occasionally crash on this scenario.

This patch fixes `MergeBlockIntoPredecessor`, making it conformant to this precondition.

Reviewers: kuhar, brzycki, chandlerc

Reviewed By: brzycki

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D58444

llvm-svn: 355105

2019-02-28 16:47:18 +00:00

33 KiB

Raw Blame History

View Raw