[llvm] [NVPTX] Support !"cluster_dim_{x,y,z}" metadata (PR #109548)

[Artem Belevich via llvm-commits]

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@@ -0,0 +1,15 @@
+; RUN: llc < %s -march=nvptx64 -mcpu=sm_90 | FileCheck %s
+; RUN: %if ptxas-12.0 %{ llc < %s -march=nvptx64 -mcpu=sm_90 | %ptxas-verify -arch=sm_90 %}
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Artem-B wrote:

I'd also add a run with pre-sm90 GPU, and switch to auto-generated checks, so it captures the "no-attributes here" case for older GPUs. 

https://github.com/llvm/llvm-project/pull/109548