ScheduleDAGInstrs: Fix fixupKills()

Rewrite fixupKills() to use the LivePhysRegs class. Simplifies the code
and fixes a bug where the CSR registers in return blocks where missed
leading to invalid kill flags. Also remove the unnecessary rule that we
wouldn't set kill flags on tied operands.

No tests as I have an upcoming commit improving MachineVerifier checks
to catch these cases in multiple existing lit tests.

llvm-svn: 304055

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/MachineScheduler.cpp b/llvm/lib/CodeGen/MachineScheduler.cpp
index dbc9d01d7d5..edc3783afa2 100644
--- a/llvm/lib/CodeGen/MachineScheduler.cpp
+++ b/llvm/lib/CodeGen/MachineScheduler.cpp
@@ -532,7 +532,7 @@ void MachineSchedulerBase::scheduleRegions(ScheduleDAGInstrs &Scheduler,
     // thumb2 size reduction is currently an exception, so the PostMIScheduler
     // needs to do this.
     if (FixKillFlags)
-        Scheduler.fixupKills(&*MBB);
+      Scheduler.fixupKills(*MBB);
   }
   Scheduler.finalizeSchedule();
 }