[clang] [HLSL] Implement the `ldexp` intrinsic (PR #138182)

[Sarah Spall via cfe-commits]

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@@ -0,0 +1,39 @@
+// 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_double_inputs(double p0, double p1) {
+  return ldexp(p0, p1);
+  // expected-error at -1  {{no matching function for call to 'ldexp'}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate template ignored}}
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spall wrote:

is it worth including these notes in these tests? They don't seem valuable to me, and can be excluded with -verify-ignore-unexpected=note

https://github.com/llvm/llvm-project/pull/138182