[clang] [llvm] [HLSL] Implement the `faceforward` intrinsic (PR #135878)

[Farzon Lotfi via cfe-commits]

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@@ -0,0 +1,63 @@
+; RUN: llc -O0 -verify-machineinstrs -mtriple=spirv-unknown-unknown %s -o - | FileCheck %s
+; RUN: %if spirv-tools %{ llc -O0 -mtriple=spirv-unknown-unknown %s -o - -filetype=obj | spirv-val --target-env vulkan1.3 %}
+
+; TODO(#136344): This test currently fails when --target-env vulkan1.3 is specified.
+; XFAIL: spirv-tools
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farzonl wrote:

we can't xfail a new test

https://github.com/llvm/llvm-project/pull/135878