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

[Farzon Lotfi via llvm-commits]

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@@ -0,0 +1,18 @@
+// RUN: %clang_cc1 %s -triple spirv-pc-vulkan-compute -verify
+
+typedef float float2 __attribute__((ext_vector_type(2)));
+
+float2 test_no_second_arg(float2 p0) {
+  return __builtin_spirv_smoothstep(p0);
+  // expected-error at -1 {{too few arguments to function call, expected 3, have 1}}
+}
+
+float2 test_no_third_arg(float2 p0) {
+  return __builtin_spirv_smoothstep(p0, p0);
+  // expected-error at -1 {{too few arguments to function call, expected 3, have 2}}
+}
+
+float2 test_too_many_arg(float2 p0) {
+  return __builtin_spirv_smoothstep(p0, p0, p0, p0);
+  // expected-error at -1 {{too many arguments to function call, expected 3, have 4}}
+}
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farzonl wrote:

you will want mixed type tests, and int tests to error on

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