DwarfUnit: Factor out calling isUnsignedDIType into a utility function so each caller of emitConstantValue doesn't have to call it separately.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208496 91177308-0d34-0410-b5e6-96231b3b80d8
DwarfUnit: Pick a winner between isTypeSigned and isUnsignedDIType.

And the winner by a nose is isUnsignedDIType, for no particular reason.

These two functions were just complements of each other and used in very
related code, so refactor callers to just use one of them.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208500 91177308-0d34-0410-b5e6-96231b3b80d8
[PowerPC] On PPC32, 128-bit shifts might be runtime calls

The counter-loops formation pass needs to know what operations might be
function calls (because they can't appear in counter-based loops). On PPC32,
128-bit shifts might be runtime calls (even though you can't use __int128 on
PPC32, it seems that SROA might form them).

Fixes PR19709.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@208501 91177308-0d34-0410-b5e6-96231b3b80d8