[MachineCombiner] Fix initialisation of LastUpdate for incremental update.
Summary:
Fixes a bogus iterator resulting from the removal of a block's first instruction at the point that incremental update is enabled.
Patch by Paul Walker.
Reviewers: fhahn, Gerolf, efriedma, MatzeB
Reviewed By: fhahn
Subscribers: aemerson, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D38734
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@315502 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed