[clang] [llvm] [HLSL] Implement the `smoothstep` intrinsic (PR #132288)

[Farzon Lotfi via llvm-commits]

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@@ -0,0 +1,60 @@
+; 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 %}
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farzonl wrote:

This should be fine. I think Steven just wanted you to add a -target-env to the spirv validator. The question I would have is if the target env is older than what we are expecting do we need to support a backport of smoothstep for older vulkan versions. That question can probably be addressed in a seperate PR though.

https://github.com/llvm/llvm-project/pull/132288