[SystemZ] Use RXSBG

Extend the previous R.SBG patches to handle XORs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186570 91177308-0d34-0410-b5e6-96231b3b80d8
[SystemZ] Generalize RxSBG SRA case

The original code only folded SRA into ROTATE ... SELECTED BITS
if there was no outer shift.  This patch splits out that check
and generalises it slightly.  The extra cases aren't really that
interesting, but this is paving the way for RNSBG support.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186571 91177308-0d34-0410-b5e6-96231b3b80d8
Add Thumb tests for the ARMv8 FP instructions that I recently added.

Also, fix the namespace for two instructions that I missed previously.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186572 91177308-0d34-0410-b5e6-96231b3b80d8
[SystemZ] Use RNSBG

This should be the last of the R.SBG patches for now.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186573 91177308-0d34-0410-b5e6-96231b3b80d8