[clang] [llvm] [HLSL] Implement the `reflect` HLSL function (PR #122992)

[Farzon Lotfi via llvm-commits]

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@@ -0,0 +1,22 @@
+; RUN: not llc -verify-machineinstrs -O0 -mtriple=spirv64-unknown-unknown %s -o /dev/null 2>&1 | FileCheck %s
+; RUN: not llc -verify-machineinstrs -O0 -mtriple=spirv32-unknown-unknown %s -o /dev/null 2>&1 | FileCheck %s
+; RUN: not %if spirv-tools %{ llc -O0 -mtriple=spirv64-unknown-unknown %s -o /dev/null 2>&1 -filetype=obj %}
+; RUN: not %if spirv-tools %{ llc -O0 -mtriple=spirv32-unknown-unknown %s -o /dev/null 2>&1 -filetype=obj %}
+
+; CHECK: LLVM ERROR: Intrinsic selection not supported for this instruction set: %{{.*}} = G_INTRINSIC intrinsic(@llvm.spv.reflect), %{{.*}}, %{{.*}}
+
+define noundef <4 x half> @reflect_half4(<4 x half> noundef %a, <4 x half> noundef %b) {
+entry:
+  %spv.reflect = call <4 x half> @llvm.spv.reflect.f16(<4 x half> %a, <4 x half> %b)
+  ret <4 x half> %spv.reflect
+}
+
+define noundef <4 x float> @reflect_float4(<4 x float> noundef %a, <4 x float> noundef %b) {
+entry:
+  %spv.reflect = call <4 x float> @llvm.spv.reflect.f32(<4 x float> %a, <4 x float> %b)
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farzonl wrote:

This function will never be evaluated. The `report_fatal_error` means we stop codegen after line 10. Please delete.

https://github.com/llvm/llvm-project/pull/122992