When breaking an anti-dependency, don't use a register which has seen

one of its aliases defined. This is conservative, but tricky subreg
corner cases are outside the primary aim of this pass.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61077 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/PostRASchedulerList.cpp

@@ -454,6 +454,7 @@ bool SchedulePostRATDList::BreakAntiDependencies() {
         assert(((KillIndices[NewReg] == -1u) != (DefIndices[NewReg] == -1u)) &&
                "Kill and Def maps aren't consistent for NewReg!");
         if (KillIndices[NewReg] == -1u &&
+            Classes[NewReg] != reinterpret_cast<TargetRegisterClass *>(-1) &&
             KillIndices[AntiDepReg] <= DefIndices[NewReg]) {
           DOUT << "Breaking anti-dependence edge on "
                << TRI->getName(AntiDepReg)