[ARM][NEON] Improve vector popcnt lowering with PADDL (PR39281)
As I suggested on PR39281, this patch uses PADDL pairwise addition to widen from the vXi8 CTPOP result to the target vector type.
This is a blocker for moving more x86 code to generic vector CTPOP expansion (P32655 + D53258) - ARM's vXi64 CTPOP currently expands, which would generate a vXi64 MUL but ARM's custom lowering expands the general MUL case and vectors aren't well handled in LegalizeDAG - improving the CTPOP lowering was a lot easier than fixing the MUL lowering for this one case......
Differential Revision: https://reviews.llvm.org/D53257
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@344512 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed