mozilla/rust — pull request #13539 by Aatch (2014-04-15 23:48:14+00:00)
Title: Improve the copying code for slices and Vec

LLVM wasn't recognising the loops as memcpy loops and was therefore failing to optimise them properly. While improving LLVM is the "proper" way to fix this, I think that these cases are important enough to warrant a little low-level optimisation.

Fixes #13472