[llvm] [AMDGPU][SIInsertWaitcnts][NFC] Introduce WaitEventSet container for events (PR #178511)

[via llvm-commits]

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@@ -321,10 +340,88 @@ unsigned getWait(AMDGPU::Waitcnt &Wait, InstCounterType T) {
   return getCounterRef(Wait, T);
 }
 
+/// A small set of events.
+class WaitEventSet {
+  unsigned Mask = 0;
+
+public:
+  WaitEventSet() = default;
+  explicit constexpr WaitEventSet(WaitEventType Event) {
+    assert((size_t)Event < sizeof(Mask) * 8 && "Not enough bits in mask!");
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vporpo wrote:

Yes, I prefer that too. Done.

https://github.com/llvm/llvm-project/pull/178511