[llvm] [AMDGPU] Measure MFMA hazard windows at their own producers (PR #225989)

[Michael Halkenhäuser via llvm-commits]

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@@ -176,6 +176,16 @@ class GCNHazardRecognizer final : public ScheduleHazardRecognizer {
   // used on a newly inserted instruction before returning from PreEmitNoops.
   void runOnInstruction(MachineInstr *MI);
 
+  /// Wait states required after \p MI, or nullopt if \p MI is not waited for.
+  /// Must return nullopt for terminators.
+  typedef function_ref<std::optional<int>(const MachineInstr &)> WindowForFn;
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mhalk wrote:

nvm: Addressed! :)

https://github.com/llvm/llvm-project/pull/225989