[SystemZ] Add sign-extending high-word loads (LBH and LHH)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191740 91177308-0d34-0410-b5e6-96231b3b80d8
SCEVExpander: Fix a regression I introduced by to eagerly adding RAII objects.

PR17425.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191741 91177308-0d34-0410-b5e6-96231b3b80d8
[SystemZ] Add zero-extending high-word loads (LLCH and LLHH)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191742 91177308-0d34-0410-b5e6-96231b3b80d8
[SystemZ] Add truncating high-word stores (STCH and STHH)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191743 91177308-0d34-0410-b5e6-96231b3b80d8
[ARM] Introduce the 'sevl' instruction in ARMv8.

This also removes the restriction on the immediate field of the 'hint'
instruction.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191744 91177308-0d34-0410-b5e6-96231b3b80d8
Remove empty directory.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191745 91177308-0d34-0410-b5e6-96231b3b80d8
[SystemZ] Add register zero extensions involving at least one high word


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191746 91177308-0d34-0410-b5e6-96231b3b80d8
Test commit. Updated comment.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191748 91177308-0d34-0410-b5e6-96231b3b80d8