[llvm] [SelectionDAG] Preserve CTTZ_ELTS lane count during expansion (PR #217982)

[Oscar Priego via llvm-commits]

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@@ -101,5 +102,21 @@ define i8 @ctz_v8i16_poison(<8 x i16> %a) {
   ret i8 %res
 }
 
+define i32 @ctz_zero_v4i1() {
+; AVX512-LABEL: ctz_zero_v4i1:
+; AVX512:         addb $5, %al
+  %res = call i32 @llvm.experimental.cttz.elts.i32.v4i1(<4 x i1> zeroinitializer, i1 false)
+  ret i32 %res
+}
+
+define i32 @ctz_zero_v8i1() {
+; AVX512-LABEL: ctz_zero_v8i1:
+; AVX512:         addb $9, %al
+  %res = call i32 @llvm.experimental.cttz.elts.i32.v8i1(<8 x i1> zeroinitializer, i1 false)
+  ret i32 %res
+}
+
 declare i8 @llvm.experimental.cttz.elts.i8.v8i16(<8 x i16>, i1)
 declare i16 @llvm.experimental.cttz.elts.i16.v4i32(<4 x i32>, i1)
+declare i32 @llvm.experimental.cttz.elts.i32.v4i1(<4 x i1>, i1)
+declare i32 @llvm.experimental.cttz.elts.i32.v8i1(<8 x i1>, i1)
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Opriego wrote:

Addressed, thanks.

https://github.com/llvm/llvm-project/pull/217982