kazuyukitanimura commented on code in PR #727: URL: https://github.com/apache/datafusion-comet/pull/727#discussion_r1698869304
########## native/core/src/common/bit.rs: ########## @@ -145,7 +145,9 @@ macro_rules! read_num_be_bytes { #[inline] pub fn memcpy(source: &[u8], target: &mut [u8]) { debug_assert!(target.len() >= source.len(), "Copying from source to target is not possible. Source has {} bytes but target has {} bytes", source.len(), target.len()); - target[..source.len()].copy_from_slice(source) + // Originally `target[..source.len()].copy_from_slice(source)` + // We use the unsafe copy method to avoid some expensive bounds checking/ + unsafe { std::ptr::copy_nonoverlapping(source.as_ptr(), target.as_mut_ptr(), source.len()) } Review Comment: `copy_from_slice` is `copy_nonoverlapping` with the `if self.len() != src.len()` check. Do you have any benchmark results to show the difference by any chance? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: github-unsubscr...@datafusion.apache.org For additional commands, e-mail: github-h...@datafusion.apache.org