Rework codegen of case ranges
 - Fix multiple issues with the way case ranges were emitted, see test
   cases details about the specific issues.

 - The root issue was not being careful about how basic blocks were
   emitted which led to them being chained together incorrectly,
   resulting in improper control flow.

 - Fixes <rdar://problem/6098585>


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@54006 91177308-0d34-0410-b5e6-96231b3b80d8
6 files changed