[clang] [llvm] [HLSL][SPIR-V] Add support for SV_Target semantic (PR #168743)

[Nathan Gauër via llvm-commits]

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@@ -2,6 +2,6 @@
 // RUN: %clang_cc1 -triple spirv-pc-vulkan1.3-pixel -finclude-default-header -x hlsl -verify -o - %s
 
 float4 main(float4 a : A) : SV_Position {
-// expected-error at -1 {{attribute 'SV_Position' is unsupported in 'pixel' shaders, requires one of the following: pixel, vertex}}
+// expected-error at -1 {{semantic 'SV_Position' is unsupported as output for stage pixel}}
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Keenuts wrote:

Ah right could be confusing, updating the language to `input/output`.

https://github.com/llvm/llvm-project/pull/168743