Create two BlockInfo entries when a live range is discontinuous through a block.
Delete the Kill and Def markers in BlockInfo. They are no longer
necessary when BlockInfo describes a continuous live range.
This only affects the relatively rare kind of basic block where a live
range looks like this:
|---x o---|
Now live range splitting can pretend that it is looking at two blocks:
|---x
o---|
This allows the code to be simplified a bit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132245
91177308-0d34-0410-b5e6-
96231b3b80d8