[llvm] [DirectX] Add GlobalDCE pass after finalize linkage pass in DirectX backend (PR #151071)

[Kaitlin Peng via llvm-commits]

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@@ -1,4 +1,4 @@
-; RUN: llc %s -mtriple=dxil-pc-shadermodel6.3-library --filetype=asm -o - | FileCheck %s
+; RUN: opt -S -passes='dxil-data-scalarization,dxil-flatten-arrays' -mtriple=dxil-unknown-shadermodel6.5-compute %s | FileCheck %s
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kmpeng wrote:

I meant do you have thoughts on if it would be better to modify the linkages instead of changing to opt?

https://github.com/llvm/llvm-project/pull/151071