Re:86 GB/s bitpacking with ARM SIMD (single thread)
by ashtonsix on Monday October 06, 2025 @10:44AM
(#45491986)
I'm assuming you're referring to BFM/EXTR? NEON absolutely improves here.
The core I developed on (Neoverse V2) has 4 SIMD ports and 6 scalar integer ports, however only 2 of those scalar ports support multicycle integer operations like the insert variant of BFM (essential for scalar packing).
More importantly, NEON progresses 16 elements per instruction instead of 1.
The core I developed on (Neoverse V2) has 4 SIMD ports and 6 scalar integer ports, however only 2 of those scalar ports support multicycle integer operations like the insert variant of BFM (essential for scalar packing).
More importantly, NEON progresses 16 elements per instruction instead of 1.