[llvm] [DXIL] Add GroupMemoryBarrierWithGroupSync intrinsic (PR #111884)

[Finn Plummer via llvm-commits]

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@@ -0,0 +1,8 @@
+; RUN: opt -S -dxil-op-lower -mtriple=dxil-pc-shadermodel6.3-library < %s | FileCheck %s --check-prefix=CHECK
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inbelic wrote:

The `check-prefix` flag shouldn't be needed when using the default

https://github.com/llvm/llvm-project/pull/111884