[LICM] update BlockColors after splitting predecessors

Update BlockColors after splitting predecessors. Do not allow splitting
EHPad for sinking when the BlockColors is not empty, so we can
simply assign predecessor's color to the new block.

Fixes PR36184

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@324916 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed