[llvm] [llvm][CodeGen] Add a new software pipeliner 'Window Scheduler' (PR #84443)

[Matt Arsenault via llvm-commits]

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@@ -300,13 +300,13 @@ void WindowScheduler::generateTripleMBB() {
   // are updated accordingly.
   for (size_t Cnt = 1; Cnt < DuplicateNum; ++Cnt) {
     for (auto *MI : OriMIs) {
-      if (MI->isPHI() || MI->isDebugInstr() ||
+      if (MI->isPHI() || MI->isMetaInstruction() ||
           (MI->isTerminator() && Cnt < DuplicateNum - 1))
         continue;
       auto *NewMI = MF->CloneMachineInstr(MI);
       DenseMap<Register, Register> NewDefs;
       // New defines are updated.
-      for (auto MO : NewMI->defs())
+      for (auto MO : NewMI->all_defs())
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arsenm wrote:

All these type of changes should have tests to go with them 

https://github.com/llvm/llvm-project/pull/84443