ADT/Optional.h: Appease msvc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175626 91177308-0d34-0410-b5e6-96231b3b80d8
Whitespace.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175627 91177308-0d34-0410-b5e6-96231b3b80d8
Fix PR15155: lost vadd/vsplat optimization.

During lowering of a BUILD_VECTOR, we look for opportunities to use a
vector splat.  When the splatted value fits in 5 signed bits, a single
splat does the job.  When it doesn't fit in 5 bits but does fit in 6,
and is an even value, we can splat on half the value and add the result
to itself.

This last optimization hasn't been working recently because of improved
constant folding.  To circumvent this, create a pseudo VADD_SPLAT that
can be expanded during instruction selection.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175632 91177308-0d34-0410-b5e6-96231b3b80d8
Revert r175626, "ADT/Optional.h: Appease msvc."

Sorry, I didn't cover +Asserts, by accident. :(

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175633 91177308-0d34-0410-b5e6-96231b3b80d8