Fix the updating of LiveIntervals after splitting a critical edge. PHI operand live ranges should always be extended, and the only successor that should be considered for extension of other ranges is the target of the split edge.
Fix the updating of LiveIntervals after splitting a critical edge. PHI operand
live ranges should always be extended, and the only successor that should be
considered for extension of other ranges is the target of the split edge.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@174935 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,chubbymaggie/asap,dslab-epfl/asap,apple/swift-llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,chubbymaggie/asap,apple/swift-llvm,chubbymaggie/asap,dslab-epfl/asap,llvm-mirror/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,dslab-epfl/asap,GPUOpen-Drivers/llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,chubbymaggie/asap,chubbymaggie/asap,apple/swift-llvm,dslab-epfl/asap,apple/swift-llvm,dslab-epfl/asap,llvm-mirror/llvm,GPUOpen-Drivers/llvm,dslab-epfl/asap,dslab-epfl/asap,apple/swift-llvm,llvm-mirror/llvm,apple/swift-llvm,chubbymaggie/asap