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

[via llvm-commits]

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@@ -4,24 +4,24 @@
 ; CHECK: error: unsupported cmpxchg
 ; CHECK: error: unsupported cmpxchg
 ; CHECK: error: unsupported cmpxchg
-define void @bitwise_i128(ptr %0, i128 %1) {
+define void @bitwise_i256(ptr %0, i256 %1) {
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gonzalobg wrote:

I think we should have two tests, one for i128 and one for i256, and the i256 should always fail, but the i128 one should fail or pass depending on whether sm < 90 or not.

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