[llvm] [NVPTX] simplified atomics-sm90.ll test (PR #125968)

[Justin Fargnoli via llvm-commits]

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@@ -1,142 +1,127 @@
 ; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
-; RUN: llc < %s -mtriple=nvptx -mcpu=sm_90 -mattr=+ptx78 | FileCheck %s --check-prefixes=CHECK
-; RUN: llc < %s -mtriple=nvptx64 -mcpu=sm_90 -mattr=+ptx78 | FileCheck %s --check-prefixes=CHECK64
-; RUN: llc < %s -mtriple=nvptx -mcpu=sm_86 -mattr=+ptx71 | FileCheck %s --check-prefixes=CHECKPTX71
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justinfargnoli wrote:

How do we know that `sm_86` doesn't support 32-bit compilation? 

https://github.com/llvm/llvm-project/pull/125968