[clang] [llvm] [HLSL] Adding HLSL `clip` function. (PR #114588)

[Farzon Lotfi via cfe-commits]

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@@ -0,0 +1,22 @@
+// RUN: %clang_cc1 -finclude-default-header -triple dxil-pc-shadermodel6.6-library %s -fnative-half-type -verify
+
+
+void test_arg_missing() {
+  __builtin_hlsl_elementwise_clip();
+ // expected-error at -1 {{too few arguments to function call, expected 1, have 0}} 
+}
+
+void test_too_many_args(float p1, float p2) {
+  __builtin_hlsl_elementwise_clip(p1, p2);
+ // expected-error at -1 {{too many arguments to function call, expected 1, have 2}} 
+}
+
+void test_first_arg_type_mismatch(bool p) {
+  __builtin_hlsl_elementwise_clip(p);
+ // expected-error at -1 {{invalid operand of type 'bool' where 'float' or a vector of such type is required}} 
+}
+
+void test_first_arg_type_mismatch_2(half p) {
+  __builtin_hlsl_elementwise_clip(p);
+ // expected-error at -1 {{invalid operand of type 'double' where 'float' or a vector of such type is required}} 
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farzonl wrote:

So this is a problem with our variadic builtin def. Could you add a version of this function that does a vector half instead. Also do a scalar `double`. So two tests in total.

https://github.com/llvm/llvm-project/pull/114588