[llvm] Handle IMPLICIT_DEF in TripleMBB for WindowScheduler (PR #179190)

[Matt Arsenault via llvm-commits]

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@@ -211,7 +211,7 @@ bool WindowScheduler::initialize() {
   };
   auto PLI = TII->analyzeLoopForPipelining(MBB);
   for (auto &MI : *MBB) {
-    if (MI.isMetaInstruction() || MI.isTerminator())
+    if ((MI.isMetaInstruction() && !MI.isImplicitDef()) || MI.isTerminator())
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arsenm wrote:

No, I don't think it's a good idea to start introducing a list of special cases here. This needs to be addressed 

https://github.com/llvm/llvm-project/pull/179190