This is the mail archive of the gcc@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: LTO and the inlining of functions only called once.


Hi,

On Mon, 12 Oct 2009, Jeff Law wrote:

> To put things in perspective, the particular person I spoke with spent 
> many days trying to understand why a particular function wasn't being 
> inlined -- presumably they'd see "grep <ugly function> logfile" as a 
> huge improvement over the days and days of twiddling sources, tuning 
> options, etc, even if that presented them with a large amount of data to 
> analyze.

If we would listen to such requests by providing the requested 
information, nothing stops users from asking to have something like that 
also for other transformations.  Like "I've spent days and days with 
analyzing why this loop isn't unrolled, I'd like to have -Winfo-unroll to 
tell me exactly when a loop is unrolled, and when it isn't for which 
reason".  Make "loop is unrolled" be $TRANSFORMATION and it becomes silly.  
I don't think this is reductio ad absurdum.  We have dump files for 
exactly such information.  Maybe the latter could be molded (via an new 
flag) into something less detailed than now, but still containing the 
larger decisions.


Ciao,
Michael.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]