Date: Tue, 9 Oct 2007 12:33:56 +1000 (EST) From: Bruce Evans <brde@optusnet.com.au> To: d@delphij.net Cc: freebsd-arch@freebsd.org Subject: Re: Why we optimize by time by default for < -O2 case? Message-ID: <20071009122751.X54949@besplex.bde.org> In-Reply-To: <470ACEA1.3030309@delphij.net> References: <470ACEA1.3030309@delphij.net>
next in thread | previous in thread | raw e-mail | index | archive | help
On Mon, 8 Oct 2007, LI Xin wrote: > I wonder why we want to optimize by time by default and not by space by > default for the system compiler, does the reasoning still hold true? -O means optimize for time if possible. > The commit log said: > > Modified files: > contrib/gcc toplev.c > Log: > Clarify revision 1.14: > Gcc 3.1's -O0 and -O1 actually optimized alignment for space, but we feel > it should optimize alignment for time like Gcc 2.95 used to. Optimization > for space should give 1-byte alignment on i386's, but doesn't quite. > > Revision Changes Path > 1.15 +0 -0 src/contrib/gcc/toplev.c Without this change, -O pessimizes for time. Bruce
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20071009122751.X54949>