perf(rust): optimize set_bytes with direct copy_nonoverlapping#3102
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borngraced wants to merge 1 commit intoapache:mainfrom
Open
perf(rust): optimize set_bytes with direct copy_nonoverlapping#3102borngraced wants to merge 1 commit intoapache:mainfrom
borngraced wants to merge 1 commit intoapache:mainfrom
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Why?
All
set_bytescallers follow the same pattern: savewriter.len()as offset, write placeholder bytes (viawrite_*/skip), then callset_bytesto back-fill. Since bounds are already guaranteed by this usage pattern, the runtime checks are redundant I guess. This allows us to optimize them away while keeping adebug_assert!for safety...What does this PR do?
Replace bounds-checked
get_mut().unwrap().copy_from_slice()with directptr::copy_nonoverlapping.Benchmark
No benchmarks yet, but the improvement should be noticeable: https://godbolt.org/z/75bhPWxfW