public inbox for glibc-cvs@sourceware.org
help / color / mirror / Atom feed
* [glibc/release/2.34/master] AArch64: Improve strchrnul
@ 2024-04-10 16:09 Wilco Dijkstra
  0 siblings, 0 replies; only message in thread
From: Wilco Dijkstra @ 2024-04-10 16:09 UTC (permalink / raw)
  To: glibc-cvs

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=b2cf48dd841ede7c57443a36d42405d39b041fa1

commit b2cf48dd841ede7c57443a36d42405d39b041fa1
Author: Wilco Dijkstra <wilco.dijkstra@arm.com>
Date:   Wed Jan 11 13:52:23 2023 +0000

    AArch64: Improve strchrnul
    
    Unroll the main loop, which improves performance slightly.
    
    Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
    (cherry picked from commit 09ebd8549b2ce5a3a6c0c7c5f3e62227faf50a99)

Diff:
---
 sysdeps/aarch64/strchrnul.S | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/sysdeps/aarch64/strchrnul.S b/sysdeps/aarch64/strchrnul.S
index 9de680b63e..9856fc5887 100644
--- a/sysdeps/aarch64/strchrnul.S
+++ b/sysdeps/aarch64/strchrnul.S
@@ -70,14 +70,22 @@ ENTRY (__strchrnul)
 
 	.p2align 4
 L(loop):
-	ldr	qdata, [src, 16]!
+	ldr	qdata, [src, 16]
+	cmeq	vhas_chr.16b, vdata.16b, vrepchr.16b
+	cmhs	vhas_chr.16b, vhas_chr.16b, vdata.16b
+	umaxp	vend.16b, vhas_chr.16b, vhas_chr.16b
+	fmov	tmp1, dend
+	cbnz	tmp1, L(end)
+	ldr	qdata, [src, 32]!
 	cmeq	vhas_chr.16b, vdata.16b, vrepchr.16b
 	cmhs	vhas_chr.16b, vhas_chr.16b, vdata.16b
 	umaxp	vend.16b, vhas_chr.16b, vhas_chr.16b
 	fmov	tmp1, dend
 	cbz	tmp1, L(loop)
-
+	sub	src, src, 16
+L(end):
 	shrn	vend.8b, vhas_chr.8h, 4		/* 128->64 */
+	add	src, src, 16
 	fmov	tmp1, dend
 #ifndef __AARCH64EB__
 	rbit	tmp1, tmp1

^ permalink raw reply	[flat|nested] only message in thread

only message in thread, other threads:[~2024-04-10 16:09 UTC | newest]

Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2024-04-10 16:09 [glibc/release/2.34/master] AArch64: Improve strchrnul Wilco Dijkstra

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).