From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Mon, 18 Feb 2008 18:40:27 -0800 From: Arjan van de Ven To: Nick Piggin Subject: Re: [PATCH 1/3] Fix Unlikely(x) == y Message-ID: <20080218184027.429cf47b@laptopd505.fenrus.org> In-Reply-To: <200802191333.53607.nickpiggin@yahoo.com.au> References: <47B70A61.9030306@tiscali.nl> <20080216094226.1e8eede1@laptopd505.fenrus.org> <200802191333.53607.nickpiggin@yahoo.com.au> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Cc: Roel Kluin <12o3l@tiscali.nl>, lkml , cbe-oss-dev@ozlabs.org, linuxppc-dev@ozlabs.org, Andi Kleen , Willy Tarreau List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, 19 Feb 2008 13:33:53 +1100 Nick Piggin wrote: > > Actually one thing I don't like about gcc is that I think it still > emits cmovs for likely/unlikely branches, which is silly (the gcc > developers seem to be in love with that instruction). If that goes > away, then branch hints may be even better. only for -Os and only if the result is smaller afaik. (cmov tends to be a performance loss most of the time so for -O2 and such it isn't used as far as I know.. it does make for nice small code however ;-) -- If you want to reach me at my work email, use arjan@linux.intel.com For development, discussion and tips for power savings, visit http://www.lesswatts.org