[X86][SSE] Generalised lowerTruncate by PACKSS to work with any 'zero/all bits' result, not just comparisons.
[X86][SSE] Generalised lowerTruncate by PACKSS to work with any 'zero/all bits' result, not just comparisons.

Added vector compare opcodes to X86TargetLowering::ComputeNumSignBitsForTargetNode

Covered by existing tests added for D22814.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@298704 91177308-0d34-0410-b5e6-96231b3b80d8

apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,apple/swift-llvm,llvm-mirror/llvm,apple/swift-llvm,llvm-mirror/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,apple/swift-llvm,llvm-mirror/llvm,apple/swift-llvm,apple/swift-llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,llvm-mirror/llvm,apple/swift-llvm