[clang] [llvm] [HLSL] Implement elementwise popcount (PR #108121)

[Farzon Lotfi via cfe-commits]

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@@ -0,0 +1,27 @@
+// RUN: %clang_cc1 -finclude-default-header
+// -triple dxil-pc-shadermodel6.6-library %s -fnative-half-type -emit-llvm-only
+// -disable-llvm-passes -verify
+
+
+double test_int_builtin(double p0) {
+  return countbits(p0);
+  // expected-error at -1 {{call to 'countbits' is ambiguous}}
+  // expected-note at hlsl/hlsl_intrinsics.h:* {{candidate function}}
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farzonl wrote:

I don't know if these notes add any value. There are cases where `-verify-ignore-unexpected` is warranted. This might be one of those cases.

https://github.com/llvm/llvm-project/pull/108121