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

[Yingwei Zheng via llvm-commits]

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@@ -199,6 +199,9 @@ class TargetSubtargetInfo : public MCSubtargetInfo {
   /// True if the subtarget should run MachinePipeliner
   virtual bool enableMachinePipeliner() const { return true; };
 
+  /// True if the subtarget should run WindowScheduler.
+  virtual bool enableWindowScheduler() const { return true; }
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dtcxzyw wrote:

> On our own DSA, this window algorithm typically can achieve a performance
improvement of over 10%.

Could you please share some performance data (e.g., SPEC benchmarks) on other non-VLIW architectures? IIRC AArch64 and PowerPC also support `MachinePipeliner`.



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