[llvm] [AMDGPU] Add stalls for DS FIFO buffer (PR #192323)

[Shilei Tian via llvm-commits]

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@@ -211,9 +253,12 @@ class HardwareUnitInfo {
   void reset() {
     AllSUs.clear();
     PrioritySUs.clear();
+    ScheduledSUs.clear();
     TotalCycles = 0;
     Type = AMDGPU::InstructionFlavor::Other;
     ProducesCoexecWindow = false;
+    BufferSize = 0;
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shiltian wrote:

Are we going to reuse _this_ HW unit for other purpose? If not, do we really need to reset this two?

https://github.com/llvm/llvm-project/pull/192323