qbit/go
1
0
Fork 0
mirror of https://github.com/golang/go synced 2024-11-19 13:14:42 -07:00
Code Releases Activity

runtime: mask a bounded slice access in hashmap evacuate

Browse Source 
Shaves a few instructions off.

Change-Id: I39f1b01ae7e770d632d5e77a6aa4b5a1f123b41a
Reviewed-on: https://go-review.googlesource.com/55090
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
This commit is contained in:
Josh Bleecher Snyder 2017-08-11 08:21:31 -07:00
parent 4b38200bfd
commit c50a9718a6
1 changed files with 1 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
src/runtime/hashmap.go
View File

@ -1129,7 +1129,7 @@ func evacuate(t *maptype, h *hmap, oldbucket uintptr) {
dst.k = add(unsafe.Pointer(dst.b), dataOffset)
dst.v = add(dst.k, bucketCnt*uintptr(t.keysize))
}
dst.b.tophash[dst.i] = top
dst.b.tophash[dst.i&(bucketCnt-1)] = top // mask dst.i as an optimization, to avoid a bounds check
if t.indirectkey {
*(*unsafe.Pointer)(dst.k) = k2 // copy pointer
} else {