[clang] [llvm] [HLSL][DXIL] Implement `refract` intrinsic (PR #147342)

[via llvm-commits]

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@@ -0,0 +1,74 @@
+// RUN: %clang_cc1 -finclude-default-header -triple dxil-pc-shadermodel6.6-library %s -fnative-half-type -emit-llvm-only -disable-llvm-passes -verify
+
+float test_no_second_arg(float3 p0) {
+  return refract(p0);
+  // expected-error at -1 {{no matching function for call to 'refract'}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate function template not viable: requires 3 arguments, but 1 was provided}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate function template not viable: requires 3 arguments, but 1 was provided}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate function template not viable: requires 3 arguments, but 1 was provided}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate function template not viable: requires 3 arguments, but 1 was provided}}
+}
+
+float test_no_third_arg(float3 p0) {
+  return refract(p0, p0);
+  // expected-error at -1 {{no matching function for call to 'refract'}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate function template not viable: requires 3 arguments, but 2 were provided}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate function template not viable: requires 3 arguments, but 2 were provided}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate function template not viable: requires 3 arguments, but 2 were provided}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate function template not viable: requires 3 arguments, but 2 were provided}}
+}
+
+float test_too_many_arg(float2 p0) {
+  return refract(p0, p0, p0, p0);
+  // expected-error at -1 {{no matching function for call to 'refract'}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate function template not viable: requires 3 arguments, but 4 were provided}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate function template not viable: requires 3 arguments, but 4 were provided}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate function template not viable: requires 3 arguments, but 4 were provided}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate function template not viable: requires 3 arguments, but 4 were provided}}
+}
+
+float test_double_inputs(double p0, double p1, double p2) {
+  return refract(p0, p1, p2);
+  // expected-error at -1  {{no matching function for call to 'refract'}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate template ignored}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate template ignored}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate template ignored}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate template ignored}}
+}
+
+float test_int_inputs(int p0, int p1, int p2) {
+  return refract(p0, p1, p2);
+  // expected-error at -1  {{no matching function for call to 'refract'}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate template ignored}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate template ignored}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate template ignored}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate template ignored}}
+}
+
+float1 test_vec1_inputs(float1 p0, float1 p1, float1 p2) {
+  return refract(p0, p1, p2);
+  // expected-error at -1  {{no matching function for call to 'refract'}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate template ignored: substitution failure [with T = float1]: no type named 'Type' in 'hlsl::__detail::enable_if<false, vector<float, 1>>'}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate template ignored: substitution failure [with T = float1]: no type named 'Type' in 'hlsl::__detail::enable_if<false, vector<float, 1>>'}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate template ignored: substitution failure [with L = 1]: no type named 'Type' in 'hlsl::__detail::enable_if<false, half>'}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate template ignored: substitution failure [with L = 1]: no type named 'Type' in 'hlsl::__detail::enable_if<false, float>'}}
+}
+
+float3 test_mixed_datatype_inputs(float3 p0, float3 p1, half p2) {
+  return refract(p0, p1, p2);
----------------
raoanag wrote:

@spall we have to rely on `refract-error.c` for such cases, do you think that is enough?

https://github.com/llvm/llvm-project/pull/147342