llvm /
scudo /
e513970d45f468575cd18192e1048804c0e13c55 [scudo][standalone] Small changes to the fastpath
There are a few things that I wanted to reorganize for a while:
- the loop that incrementally goes through classes on failure looked
horrible in assembly, mostly because of `LIKELY`/`UNLIKELY` within
the loop. So remove those, we are already in an unlikely scenario
- hooks are not used by default on Android/Fuchsia/etc so mark the
tests for the existence of the weak functions as unlikely
- mark of couple of conditions as likely/unlikely
- in `reallocate`, the old size was computed again while we already
have it in a variable. So just use the one we have.
- remove the bitwise AND trick and use a logical AND, that has one
less test by using a purposeful underflow when `Size` is 0 (I
actually looked at the assembly of the previous code to steal that
trick)
- move the read of the options closer to where they are used, mark them
as `const`
Overall this makes things a tiny bit faster, but cleaner.
Differential Revision: https://reviews.llvm.org/D92689
GitOrigin-RevId: 3f70987b352c44329db8f339d4c537a20cc98329
1 file changed