On 05/22/2013 11:20 PM, Steven Bosscher wrote:
On Thu, May 23, 2013 at 4:07 AM, Jeff Law wrote:
On 05/22/2013 04:07 PM, Steven Bosscher wrote:
The problem here is two things:
1. Many GCC developers still don't fully grasp the difference between
cfglayout mode and the older cfgrtl mode.
Absolutely true. I'd actually love it if someone (you?) could write up the
basics of cfglayout mode. Why does it exist, what things should a developer
need to know about it, etc.
I did that already, way back in 2006, based on a presentation I gave
at the Moscow Gelato meeting (see attachment). I first posted it as a
patch for doc/cfg.texi (twice) but it never got reviewed, so I put it
on the GCC Wiki instead: http://gcc.gnu.org/wiki/cfglayout_mode
The change-over to MoinMoin mangled the page markup so it's a bit
messy right now. It's also 7 year old text that hasn't been updated to
reflect the current state of the compiler (with almost all pre
register allocator passes working in cfglayout mode).
I will clean it up again and create a new diff for cfg.texi.
Thanks. I wasn't aware of that wiki page. I'll be reading it today :-)
jeff
