[clang] [HLSL] Implement the `lit` intrinsic (PR #134171)

[Deric C. via cfe-commits]

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@@ -0,0 +1,37 @@
+// RUN: %clang_cc1 -std=hlsl202y -finclude-default-header -x hlsl -triple dxil-pc-shadermodel6.6-library %s -fnative-half-type -emit-llvm-only -disable-llvm-passes -verify
+
+double4 test_double_inputs(double p0, double p1, double p2) {
+  return lit(p0, p1, p2);
+  // expected-error at -1 {{call to deleted function 'lit'}}
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Icohedron wrote:

I think these should be ambiguity errors rather than call to deleted function errors, but I'm not sure of an easy way to do this without also allowing implicit vector truncation.

https://github.com/llvm/llvm-project/pull/134171