[clang] [llvm] [NVPTX] Add pm_event intrinsics (PR #141278)

[Artem Belevich via cfe-commits]

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@@ -177,6 +177,7 @@ let Attributes = [NoReturn] in {
 }
 let Attributes = [NoThrow] in {
   def __nvvm_nanosleep : NVPTXBuiltinSMAndPTX<"void(unsigned int)", SM_70, PTX63>;
+  def __nvvm_pm_event_mask : NVPTXBuiltin<"void(unsigned short)">;
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Artem-B wrote:

The argument must be `_Constant unsigned short` as we can't lower non-imediate values.
https://github.com/llvm/llvm-project/blob/66a2d4b1e7b54a906990d8cee6174c228604830b/clang/include/clang/Basic/Builtins.td#L83

https://github.com/llvm/llvm-project/pull/141278