We were calling llvm_unreachable() when failing to optimize the
branch into if case. However, it is still possible for us
to structurize the CFG by duplicating blocks even if this optimization
fails.
Reviewed-by: Vincent Lejeune<vljn at ovi.com>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192813 91177308-0d34-0410-b5e6-96231b3b80d8
