[X86] Add test cases for suboptimal insertion of a vXi1 vector into a larger vector with zeros in the lower elements and undef upper elements.
[X86] Add test cases for suboptimal insertion of a vXi1 vector into a larger vector with zeros in the lower elements and undef upper elements.

Currently we generate kshifts to clear both the upper and lower
elements, but we only need one kshift.

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@369223 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,llvm-mirror/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,GPUOpen-Drivers/llvm,llvm-mirror/llvm