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| author | Siddhesh Poyarekar <siddhesh@sourceware.org> | 2017-12-13 18:50:27 +0530 |
|---|---|---|
| committer | Wilco Dijkstra <wdijkstr@arm.com> | 2019-09-06 16:56:45 +0100 |
| commit | 7f690fafad5013d1f21fd434a4b4f2482128b97c (patch) | |
| tree | c476b1032eaf0c81db3b6be5e0b6d7479b6849e1 | |
| parent | 40df047b3b3f53895c7f75267d7f57a643678da5 (diff) | |
| download | glibc-7f690fafad5013d1f21fd434a4b4f2482128b97c.tar.gz glibc-7f690fafad5013d1f21fd434a4b4f2482128b97c.tar.xz glibc-7f690fafad5013d1f21fd434a4b4f2482128b97c.zip | |
aarch64: Improve strcmp unaligned performance
Replace the simple byte-wise compare in the misaligned case with a dword compare with page boundary checks in place. For simplicity I've chosen a 4K page boundary so that we don't have to query the actual page size on the system. This results in up to 3x improvement in performance in the unaligned case on falkor and about 2.5x improvement on mustang as measured using bench-strcmp. * sysdeps/aarch64/strcmp.S (misaligned8): Compare dword at a time whenever possible. (cherry picked from commit 2bce01ebbaf8db52ba4a5635eb5744f989cdbf69)
| -rw-r--r-- | ChangeLog | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog index 20d98f0822..436aee29ea 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,10 @@ 2019-09-06 Siddhesh Poyarekar <siddhesh@sourceware.org> + * sysdeps/aarch64/strcmp.S (misaligned8): Compare dword at a + time whenever possible. + +2019-09-06 Siddhesh Poyarekar <siddhesh@sourceware.org> + * sysdeps/aarch64/memcmp.S: Widen comparison to 16 bytes at a time. |