The hash-table uses a metadata table inspired by swisstable, so we should be able to benefit from SIMD probing. The difficulty is that atomic group loads must be aligned, causing us to lose some hash entropy. I ran some benchmarks previously and found a small regression from essentially copy-pasting the x86 SIMD implementation from hashbrown, so maybe there's not really much we can do here.
There's also questions about whether mixed-sized atomic accesses are sound on x86, but we should at least be able to benefit on other platforms.
The hash-table uses a metadata table inspired by swisstable, so we should be able to benefit from SIMD probing. The difficulty is that atomic group loads must be aligned, causing us to lose some hash entropy. I ran some benchmarks previously and found a small regression from essentially copy-pasting the x86 SIMD implementation from
hashbrown, so maybe there's not really much we can do here.There's also questions about whether mixed-sized atomic accesses are sound on x86, but we should at least be able to benefit on other platforms.