[clang] [llvm] [NVPTX] Add clang builtin for `__nvvm_reflect` intrinsic (PR #81277)

[Artem Belevich via cfe-commits]

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@@ -159,6 +159,7 @@ BUILTIN(__nvvm_read_ptx_sreg_pm3, "i", "n")
 
 BUILTIN(__nvvm_prmt, "UiUiUiUi", "")
 BUILTIN(__nvvm_exit, "v", "r")
+BUILTIN(__nvvm_reflect, "UicC*", "r")
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Artem-B wrote:

Now that we're exposing it to the end users. We should probably document what it does.
Probably somewhere in https://clang.llvm.org/docs/LanguageExtensions.html



https://github.com/llvm/llvm-project/pull/81277