Added command-line option to output llvm-cov to file.

Added -o option to llvm-cov. If no output file is specified, it defaults
to STDOUT.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193899 91177308-0d34-0410-b5e6-96231b3b80d8
Fix PR17764

- When selecting BLEND from vselect, the operands need swapping as due to the
  difference between vselect and SSE/AVX's BLEND insn



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193900 91177308-0d34-0410-b5e6-96231b3b80d8