This is the mail archive of the libc-alpha@sourceware.org mailing list for the glibc project.

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]
Other format:	[Raw text]

[PATCH] hppa: Optimize atomic_compare_and_exchange_val_acq

From: John David Anglin <dave dot anglin at bell dot net>
To: GNU C Library <libc-alpha at sourceware dot org>
Cc: deller at kernel dot org, Carlos O'Donell <carlos at redhat dot com>, Mike Frysinger <vapier at gentoo dot org>, Aurelien Jarno <aurelien at aurel32 dot net>
Date: Thu, 22 Sep 2016 10:14:11 -0400
Subject: [PATCH] hppa: Optimize atomic_compare_and_exchange_val_acq
Authentication-results: sourceware.org; auth=none

The attached patch replaces the conditional branch tests in atomic_compare_and_exchange_val_acq with
conditional instruction nullification.  This avoids the stalls associated with conditional branches and the resulting
code is shorter.  There are no branches in the fast path when the operation is successful.

The change was intended as an optimization but tst-stack4 now passes.

Please install.

Thanks,
Dave
--
John David Anglin	dave.anglin@bell.net

Attachment: submitted-atomic-machine.diff.txt
Description: Text document

Follow-Ups:
- Re: [PATCH] hppa: Optimize atomic_compare_and_exchange_val_acq
  - From: Carlos O'Donell

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]