[llvm] [AArch64] Replace uaddlv with addv for popcount operation (PR #121934)

[David Green via llvm-commits]

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@@ -243,6 +254,30 @@ define void @ctpop_i64() {
 }
 
 
+define i64 @popcnt(i64 %a, ptr %p) {
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davemgreen wrote:

The new test is nicer than one that goes through globals, if you wanted to remove the old one :)

https://github.com/llvm/llvm-project/pull/121934