This is the mail archive of the
mailing list for the GCC project.
Re: [PATCH] PR middle-end/18293: Fast-path expand_mult for 2^N
- From: Mike Stump <mrs at apple dot com>
- To: Roger Sayle <roger at eyesopen dot com>
- Cc: Zack Weinberg <zack at codesourcery dot com>, gcc-patches at gcc dot gnu dot org
- Date: Wed, 8 Dec 2004 10:03:18 -0800
- Subject: Re: [PATCH] PR middle-end/18293: Fast-path expand_mult for 2^N
On Tuesday, December 7, 2004, at 05:51 PM, Roger Sayle wrote:
[But perhaps my understanding of GCC's middle-end is unduly influencing
my preferred coding style].
Yes, I think so. The code should be targeted first, at humans. When
the profile proves that it is important to not do that, then we
deviate. I haven't seen the data for this one case, but, I can't
imagine that it blows up by more than 20%.
If you are worried about better turn around for developers, the first
think I would like to see is better dependancy tracking for tm.h files,
so that you can edit a single comment in a port file, and recompile,
and have nothing recompile, instead of half of the entire world.
I was thinking about doing something radical like saving every -E
during compilation, and doing a move if changed on them all to produce
the .o files in much the same spirit as one of the existing stamp
I'd expect the benefit would be better compile times for all port
maintainers, and the improvement would be large.