InstCombine: Propagate exact for (sdiv -X, C) -> (sdiv X, -C)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222623 91177308-0d34-0410-b5e6-96231b3b80d8
InstCombine: Propagate exact for (sdiv X, Y) -> (udiv X, Y)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222624 91177308-0d34-0410-b5e6-96231b3b80d8
InstCombine: Propagate exact for (sdiv X, Pow2) -> (udiv X, Pow2)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222625 91177308-0d34-0410-b5e6-96231b3b80d8