[llvm] [CodeGen] Add widening support for ISD::CTTZ_ELTS (PR #205841)

[Luke Lau via llvm-commits]

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@@ -201,4 +201,64 @@ define i16 @ctz_v8i1_i16_ret(<8 x i1> %a) {
   ret i16 %res
 }
 
+define i32 @ctz_v3i32(<3 x i32> %a) {
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lukel97 wrote:

Agreed we can handle it in another patch, thanks for checking. By the way was an LLM used to assist in this PR? It's fine to use one but it should be disclosed as per the AI policy: https://llvm.org/docs/AIToolPolicy.html

https://github.com/llvm/llvm-project/pull/205841