[clang] [llvm] [DirectX] Implement UseNativeLowPrecision shader flag analysis (PR #134288)

[Farzon Lotfi via llvm-commits]

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@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -fnative-half-type -finclude-default-header -triple dxil-pc-shadermodel6.3-library -emit-llvm -disable-llvm-passes -o - %s | FileCheck %s --check-prefix=FLAG
+// RUN: %clang_cc1 -finclude-default-header -triple dxil-pc-shadermodel6.3-library -emit-llvm -disable-llvm-passes -o - %s | FileCheck %s --check-prefix=NOFLAG
+
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farzonl wrote:

Should we add a `// RUN: %clang_dxc` runline? We typically hve only used it to test the driver, but I kind of feel like your we need to confirm `-enable-16bit-types` and  `-fnative-half-type` do the same thing.

https://github.com/llvm/llvm-project/pull/134288