[clang] [llvm] Add step builtins and step HLSL function to DirectX and SPIR-V backend (PR #106471)

[Farzon Lotfi via cfe-commits]

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@@ -0,0 +1,31 @@
+// RUN: %clang_cc1 -finclude-default-header -triple dxil-pc-shadermodel6.6-library %s -fnative-half-type -disable-llvm-passes -verify -verify-ignore-unexpected
+
+void test_too_few_arg()
+{
+  return __builtin_hlsl_step();
+  // expected-error at -1 {{too few arguments to function call, expected 2, have 0}}
+}
+
+void test_too_many_arg(float2 p0)
+{
+  return __builtin_hlsl_step(p0, p0, p0);
+  // expected-error at -1 {{too many arguments to function call, expected 2, have 3}}
+}
+
+bool builtin_bool_to_float_type_promotion(bool p1)
+{
+  return __builtin_hlsl_step(p1, p1);
+  // expected-error at -1 {passing 'bool' to parameter of incompatible type 'float'}}
+}
+
+bool builtin_step_int_to_float_promotion(int p1)
+{
+  return __builtin_hlsl_step(p1, p1);
+  // expected-error at -1 {{passing 'int' to parameter of incompatible type 'float'}}
+}
+
+bool2 builtin_step_int2_to_float2_promotion(int2 p1)
+{
+  return __builtin_hlsl_step(p1, p1);
+  // expected-error at -1 {{passing 'int2' (aka 'vector<int, 2>') to parameter of incompatible type '__attribute__((__vector_size__(2 * sizeof(float)))) float' (vector of 2 'float' values)}}
+}
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farzonl wrote:

add a new line

https://github.com/llvm/llvm-project/pull/106471