[clang] [llvm] Add length HLSL function to DirectX Backend (PR #101256)

[Farzon Lotfi via cfe-commits]

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@@ -0,0 +1,131 @@
+; RUN: opt -S  -dxil-intrinsic-expansion  < %s | FileCheck %s --check-prefixes=CHECK,EXPCHECK
+; RUN: opt -S  -dxil-op-lower -mtriple=dxil-pc-shadermodel6.3-library < %s | FileCheck %s --check-prefixes=CHECK,DOPCHECK
+
+declare half @llvm.fabs.f16(half)
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farzonl wrote:

We ussually add a comment at the top describing the test case. 
Like for clamp we said:
`; Make sure dxil operation function calls for clamp/uclamp are generated for half/float/double/i16/i32/i64.`



https://github.com/llvm/llvm-project/pull/101256