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

[Steven Perron 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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s-perron wrote:

I would like to start having the validation step to include the target environment. This will give more robust testing.
```suggestion
; RUN: %if spirv-tools %{ llc -O0 -mtriple=spirv-unknown-unknown %s -o - -filetype=obj | spirv-val --target-env vulkan1.2 %}

```

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