[clang] [HLSL] Implement the dst HLSL Function (PR #133828)

[Ashley Coleman via cfe-commits]

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@@ -0,0 +1,57 @@
+// RUN: %clang_cc1 -finclude-default-header -x hlsl -triple dxil-pc-shadermodel6.2-library %s -fnative-half-type -emit-llvm -disable-llvm-passes -o - | FileCheck %s
+
+
+// CHECK-LABEL: linkonce_odr noundef nofpclass(nan inf) <4 x float> @_ZN4hlsl8__detail8dst_implIfEEDv4_T_S3_S3_(
+// CHECK-SAME: <4 x float> noundef nofpclass(nan inf) [[P:%.*]], <4 x float> noundef nofpclass(nan inf) [[Q:%.*]]) #[[ATTR0:[0-9]+]] { 
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V-FEXrt wrote:

Same idea here. We don't care about `noundef nofpclass(nan inf)` stuff so the check shouldn't require them

https://github.com/llvm/llvm-project/pull/133828