[SystemZ] Reapply: Add definitions of LFH and STFH

Originally committed as r191661, but reverted because it changed the matching
order of comparisons on some hosts.  That should have been fixed by r191735.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191738 91177308-0d34-0410-b5e6-96231b3b80d8
[SystemZ] Use upper words of GR64s for codegen

This just adds the basics necessary for allocating the upper words to
virtual registers (move, load and store).  The move support is parameterised
in a way that makes it easy to handle zero extensions, but the associated
zero-extend patterns are added by a later patch.

The easiest way of testing this seemed to be add a new "h" register
constraint for high words.  I don't expect the constraint to be useful
in real inline asms, but it should work, so I didn't try to hide it
behind an option.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191739 91177308-0d34-0410-b5e6-96231b3b80d8
[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
[ARM] Remove an unused function from the disassembler.

Pointed out by Joerg.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191749 91177308-0d34-0410-b5e6-96231b3b80d8
[SystemZ] Add patterns to load a constant into a high word (IIHF)

Similar to low words, we can use the shorter LLIHL and LLIHH if it turns
out that the other half of the GR64 isn't live.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191750 91177308-0d34-0410-b5e6-96231b3b80d8
[SystemZ] Allow selects with a high-word destination


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191751 91177308-0d34-0410-b5e6-96231b3b80d8
Fix a typo in the documentation. Thanks to Diana Vasile for the patch

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191752 91177308-0d34-0410-b5e6-96231b3b80d8
[SystemZ] Allow integer insertions with a high-word destination


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191753 91177308-0d34-0410-b5e6-96231b3b80d8
[SystemZ] Allow integer OR involving high words


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191755 91177308-0d34-0410-b5e6-96231b3b80d8
Remove several unused variables.

Patch by Alp Toker.

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[SystemZ] Allow integer XOR involving high words


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191759 91177308-0d34-0410-b5e6-96231b3b80d8
[SystemZ] Allow integer AND involving high words


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191762 91177308-0d34-0410-b5e6-96231b3b80d8
Add non-blocking Wait() for launched processes

- New ProcessInfo class to encapsulate information about child processes.
- Generalized the Wait() to support non-blocking wait on child processes.
- ExecuteNoWait() now returns a ProcessInfo object with information about
  the launched child. Users will be able to use this object to
  perform non-blocking wait.
- ExecuteNoWait() now accepts an ExecutionFailed param that tells if execution
  failed or not.

These changes will allow users to implement basic process parallel
tools.

Differential Revision: http://llvm-reviews.chandlerc.com/D1728


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