From mboxrd@z Thu Jan 1 00:00:00 1970 From: Grant Grundler Date: Fri, 19 Sep 2003 17:29:41 +0000 Subject: Re: Inefficient ia64 system call implementation in glibc Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org On Fri, Sep 19, 2003 at 09:32:18AM -0700, H. J. Lu wrote: > The inline ia64 system call assumes all values passed to kernel are > signed 64bit. It does sign extension if the incoming arg is not signed > 64bit. AFAIK, All compilers do this. The HPUX performance team was on a rampage to replace signed variables with "unsigned" whereever possible just for this reason. See example 2 in section "4.5.1 Data Types" (page 16 of 17): http://devresource.hp.com/STK/partner/PA_PerfGuide_vs2.pdf BTW, don't dismiss this just because it talks about parisc. I'd guess +90% of this paper applies to ia64 as well. grant