[clang] [llvm] [NVPTX] Add NVVMUpgradeAnnotations pass to cleanup legacy annotations (PR #119261)

[Alex MacLean via llvm-commits]

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@@ -1270,77 +1270,21 @@ exit:
 ; MODULE: attributes #[[ATTR1:[0-9]+]] = { convergent nocallback nounwind }
 ; MODULE: attributes #[[ATTR2:[0-9]+]] = { convergent nocallback nofree nounwind willreturn }
 ; MODULE: attributes #[[ATTR3:[0-9]+]] = { nocallback nofree nosync nounwind willreturn memory(inaccessiblemem: write) }
-; MODULE: attributes #[[ATTR4]] = { "kernel" }
-; MODULE: attributes #[[ATTR5]] = { nosync memory(none) }
+; MODULE: attributes #[[ATTR4]] = { "kernel" "nvvm.kernel" }
+; MODULE: attributes #[[ATTR5]] = { "kernel" }
+; MODULE: attributes #[[ATTR6]] = { nosync memory(none) }
 ;.
 ; CGSCC: attributes #[[ATTR0]] = { "llvm.assume"="ompx_aligned_barrier" }
 ; CGSCC: attributes #[[ATTR1:[0-9]+]] = { convergent nocallback nounwind }
 ; CGSCC: attributes #[[ATTR2:[0-9]+]] = { convergent nocallback nofree nounwind willreturn }
 ; CGSCC: attributes #[[ATTR3:[0-9]+]] = { nocallback nofree nosync nounwind willreturn memory(inaccessiblemem: write) }
-; CGSCC: attributes #[[ATTR4]] = { "kernel" }
-; CGSCC: attributes #[[ATTR5]] = { nosync memory(none) }
+; CGSCC: attributes #[[ATTR4]] = { "kernel" "nvvm.kernel" }
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AlexMaclean wrote:

Unfortunately, I think we do. "kernel" is really more like "OpenMP kernel" and the semantics for this do not seem to be a perfect match for "nvvm.kernel". For example, `@multiple_blocks_functions_non_kernel_effects_2` in this test has "kernel" but is not an nvvm kernel. I'm vary unfamiliar with the OpenMP semantics so I thought keeping it separate would be the safest approach, it also may be clearest to have a common "nvvm.*" prefix for all attributes currently represented as nvvm.annotations. 

https://github.com/llvm/llvm-project/pull/119261