[llvm] [NVPTX] add support for 128-bit atomics (PR #154852)

[Artem Belevich via llvm-commits]

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@@ -2200,6 +2204,36 @@ defm INT_PTX_SATOM_MIN  : ATOM2_minmax_impl<"min">;
 defm INT_PTX_SATOM_OR   : ATOM2_bitwise_impl<"or">;
 defm INT_PTX_SATOM_XOR  : ATOM2_bitwise_impl<"xor">;
 
+// atom.*.b128
+
+let mayLoad = 1, mayStore = 1, hasSideEffects = 1 in {
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Artem-B wrote:

We may want to put PTX/SM constraints.

https://github.com/llvm/llvm-project/pull/154852