[llvm] [AArch64] Combine vector FNEG+FMA into `FNML[A|S]` (PR #167900)

[Benjamin Maxwell via llvm-commits]

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@@ -43,10 +48,11 @@ define <8 x double> @simple_symmetric_muladd4(<8 x double> %a, <8 x double> %b)
 ; CHECK-NEXT:    zip1 v17.2d, v5.2d, v7.2d
 ; CHECK-NEXT:    zip2 v5.2d, v5.2d, v7.2d
 ; CHECK-NEXT:    dup v6.2d, x8
-; CHECK-NEXT:    fmla v3.2d, v6.2d, v16.2d
-; CHECK-NEXT:    fmla v4.2d, v6.2d, v0.2d
-; CHECK-NEXT:    fmla v17.2d, v6.2d, v2.2d
-; CHECK-NEXT:    fmla v5.2d, v6.2d, v1.2d
+; CHECK-NEXT:    ptrue p0.d, vl2
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MacDue wrote:

Note: These test changes ago away with https://github.com/llvm/llvm-project/pull/167900#discussion_r2571407072

https://github.com/llvm/llvm-project/pull/167900