[Sparc] Emit large negative adjustments to SP/FP with sethi+xor instead of sethi+or. This generates correct code for both sparc32 and sparc64.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@195576 91177308-0d34-0410-b5e6-96231b3b80d8