[llvm] [AMDGPU] Add eventMask function in WaitcntGenerator class (NFC) (PR #85210)

[Jay Foad via llvm-commits]

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@@ -485,6 +485,15 @@ class WaitcntGenerator {
   virtual AMDGPU::Waitcnt getAllZeroWaitcnt(bool IncludeVSCnt) const = 0;
 
   virtual ~WaitcntGenerator() = default;
+
+  // Create a mask value from the initializer list of wait event types.
+  unsigned eventMask(std::initializer_list<WaitEventType> Events) const {
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jayfoad wrote:

Doesn't this function need to be constexpr to let you use it in the initializer of static data? (I am not a C++ expert!)

https://github.com/llvm/llvm-project/pull/85210