misched: Don't consider artificial edges weak edges.

For now be more conservative in case other out-of-tree schedulers rely
on the old behavior of artificial edges.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167808 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/PostRASchedulerList.cpp b/lib/CodeGen/PostRASchedulerList.cpp
index 4284c42..f37fc82 100644
--- a/lib/CodeGen/PostRASchedulerList.cpp
+++ b/lib/CodeGen/PostRASchedulerList.cpp
@@ -581,7 +581,7 @@
 void SchedulePostRATDList::ReleaseSucc(SUnit *SU, SDep *SuccEdge) {
   SUnit *SuccSU = SuccEdge->getSUnit();
 
-  if (SuccEdge->isArtificial()) {
+  if (SuccEdge->isWeak()) {
     --SuccSU->WeakPredsLeft;
     return;
   }