[llvm] [AMDGPU] Add support for GFX12 expert scheduling mode 2 (PR #170319)

[Nicolai Hähnle via llvm-commits]

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@@ -2741,7 +2979,14 @@ bool SIInsertWaitcnts::run(MachineFunction &MF) {
   AMDGPU::IsaVersion IV = AMDGPU::getIsaVersion(ST->getCPU());
 
   if (ST->hasExtendedWaitCounts()) {
-    MaxCounter = NUM_EXTENDED_INST_CNTS;
+    if (ST->hasSoftwareHazardMode() &&
+        (MF.getFunction()
+             .getFnAttribute("amdgpu-software-hazard-mode")
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nhaehnle wrote:

That almost makes it feel like it has to be a subtarget feature?

https://github.com/llvm/llvm-project/pull/170319