[clang] [llvm] [HLSL] AST support for WaveSize attribute. (PR #101240)

[Chris B via cfe-commits]

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@@ -0,0 +1,20 @@
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.8-pixel -x hlsl %s  -verify
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.8-vertex -x hlsl %s  -verify
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.8-geometry -x hlsl %s  -verify
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.8-hull -x hlsl %s  -verify
+// RUN: %clang_cc1 -triple dxil-pc-shadermodel6.8-domain -x hlsl %s  -verify
+
+#if __SHADER_TARGET_STAGE == __SHADER_STAGE_PIXEL
+// expected-error at +10 {{attribute 'WaveSize' is unsupported in 'pixel' shaders, requires one of the following: compute, amplification, mesh}}
+#elif __SHADER_TARGET_STAGE == __SHADER_STAGE_VERTEX
+// expected-error at +8 {{attribute 'WaveSize' is unsupported in 'vertex' shaders, requires one of the following: compute, amplification, mesh}}
+#elif __SHADER_TARGET_STAGE == __SHADER_STAGE_GEOMETRY
+// expected-error at +6 {{attribute 'WaveSize' is unsupported in 'geometry' shaders, requires one of the following: compute, amplification, mesh}}
+#elif __SHADER_TARGET_STAGE == __SHADER_STAGE_HULL
+// expected-error at +4 {{attribute 'WaveSize' is unsupported in 'hull' shaders, requires one of the following: compute, amplification, mesh}}
+#elif __SHADER_TARGET_STAGE == __SHADER_STAGE_DOMAIN
+// expected-error at +2 {{attribute 'WaveSize' is unsupported in 'domain' shaders, requires one of the following: compute, amplification, mesh}}
+#endif
+[WaveSize(16)]
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llvm-beanz wrote:

If you put something like `// #WaveSize` at the end of the line here, the checks above can all be `@#WaveSize` instead of line offsets.

https://github.com/llvm/llvm-project/pull/101240