[llvm] [AArch64] Improve scalar and Neon popcount with SVE CNT. (PR #143870)

[Paul Walker via llvm-commits]

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@@ -577,11 +670,25 @@ define <8 x i16> @popcount8x16(<8 x i16> %0) {
 ; CHECKO0-NEXT:    uaddlp v0.8h, v0.16b
 ; CHECKO0-NEXT:    ret
 ;
-; CHECK-LABEL: popcount8x16:
-; CHECK:       // %bb.0: // %Entry
-; CHECK-NEXT:    cnt v0.16b, v0.16b
-; CHECK-NEXT:    uaddlp v0.8h, v0.16b
-; CHECK-NEXT:    ret
+; NEON-LABEL: popcount8x16:
+; NEON:       // %bb.0: // %Entry
+; NEON-NEXT:    cnt v0.16b, v0.16b
+; NEON-NEXT:    uaddlp v0.8h, v0.16b
+; NEON-NEXT:    ret
+;
+; DOT-LABEL: popcount8x16:
+; DOT:       // %bb.0: // %Entry
+; DOT-NEXT:    cnt v0.16b, v0.16b
+; DOT-NEXT:    uaddlp v0.8h, v0.16b
+; DOT-NEXT:    ret
+;
+; SVE-LABEL: popcount8x16:
+; SVE:       // %bb.0: // %Entry
+; SVE-NEXT:    ptrue p0.h, vl8
+; SVE-NEXT:    // kill: def $q0 killed $q0 def $z0
+; SVE-NEXT:    cnt z0.h, p0/m, z0.h
+; SVE-NEXT:    // kill: def $q0 killed $q0 killed $z0
+; SVE-NEXT:    ret
----------------
paulwalker-arm wrote:

Thanks for the data.  There's nothing specific I'm worried about, I just wanted to double check based on the output.  This all looks good to me.  

https://github.com/llvm/llvm-project/pull/143870