[llvm] [LV] Add support for extended fadd reductions (PR #178447)

[Sander de Smalen via llvm-commits]

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@@ -4062,11 +4062,10 @@ tryToMatchAndCreateExtendedReduction(VPReductionRecipe *Red, VPCostContext &Ctx,
             ExtRedCost = Ctx.TTI.getPartialReductionCost(
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sdesmalen-arm wrote:

Yes it did in #163975, e.g.
https://github.com/llvm/llvm-project/pull/163975/changes#diff-81471f2591e3d4702e41642c913fe48499be3c053fefb599ef96a2b61998854aR339-R341
(some of the other targets already had a check for `if (Opcode != Instruction::Add) return Invalid;`.

https://github.com/llvm/llvm-project/pull/178447