Mark i64 SETCC as expand so it is turned into a SELECT_CC.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182227 91177308-0d34-0410-b5e6-96231b3b80d8
Implement spill and fill of I64Regs.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182228 91177308-0d34-0410-b5e6-96231b3b80d8