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

[Farzon Lotfi via cfe-commits]

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@@ -0,0 +1,10 @@
+; RUN: not opt -S -dxil-op-lower -mtriple=dxil-pc-shadermodel6.3-library %s 2>&1 | FileCheck %s
+
+; DXIL operation ctpop does not support double overload type
+; CHECK: invalid intrinsic signature
+
+define noundef double @countbits_double(double noundef %a) {
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farzonl wrote:

should we test for `float`?

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