[llvm] [SPIR-V] Add definitions and fix implementation for atomic builtins (PR #106107)

[Vyacheslav Levytskyy via llvm-commits]

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@@ -0,0 +1,16 @@
+; RUN: llc -O0 -mtriple=spirv64-unknown-unknown %s -o - | FileCheck %s
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VyacheslavLevytskyy wrote:

Let's add `-verify-machineinstrs` for each new test?

https://github.com/llvm/llvm-project/pull/106107