[PATCH] D67645: [aarch64] add def-pats for dot product

[Sebastian Pop via Phabricator via llvm-commits]

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Comment at: llvm/lib/Target/AArch64/AArch64InstrInfo.td:7080
+             (i32 (ADDVv4i32v
+              (DOT (DUPv4i32gpr node:$Vo), node:$Vm, node:$Vn)))>;
+
----------------
I think there is an error in this case: as we duplicate the original value $Vo across the 4 lanes of the dot product, and then in the end we do the ADDV reduction across lanes, we end up with 4 times the original value.

I will prepare an updated patch to fix this.


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  https://reviews.llvm.org/D67645/new/

https://reviews.llvm.org/D67645