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

[Farzon Lotfi via llvm-commits]

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@@ -0,0 +1,44 @@
+// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py UTC_ARGS: --version 5
+
+// RUN: %clang_cc1 -O1 -triple spirv-pc-vulkan-compute %s -emit-llvm -o - | FileCheck %s
+
+typedef float float2 __attribute__((ext_vector_type(2)));
+typedef float float3 __attribute__((ext_vector_type(3)));
+typedef float float4 __attribute__((ext_vector_type(4)));
+
+// CHECK-LABEL: define spir_func float @test_smoothstep_float(
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farzonl wrote:

> Yes. It also supports int types so will add both to the tests.

If thats true then you need to remove the `hasFloatingRepresentation()` checks for all the SPIRV parts of the code and only keep them for the HLSL parts.

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