CellSPU:

CellSPU:
- Fix v2[if]64 vector insertion code before IBM files a bug report.
- Ensure that zero (0) offsets relative to $sp don't trip an assert
  (add $sp, 0 gets legalized to $sp alone, tripping an assert)
- Shuffle masks passed to SPUISD::SHUFB are now v16i8 or v4i32

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60358 91177308-0d34-0410-b5e6-96231b3b80d8