Index: lib/Target/AMDGPU/SIInsertWaitcnts.cpp
===================================================================
--- lib/Target/AMDGPU/SIInsertWaitcnts.cpp
+++ lib/Target/AMDGPU/SIInsertWaitcnts.cpp
@@ -1868,6 +1868,7 @@
   BlockVisitedSet.clear();
   VCCZBugHandledSet.clear();
   LoopWaitcntDataMap.clear();
+  BlockWaitcntProcessedSet.clear();
 
   // Walk over the blocks in reverse post-dominator order, inserting
   // s_waitcnt where needed.