[PostRASink] extend the live-in check for all aliased registers

Extend the live-in check for all aliased registers so that we can
allow sinking Copy instructions when only implicit def is in successor's
live-in.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331072 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed