This is the mail archive of the
mailing list for the GCC project.
Re: gcc compile-time performance
- From: Richard Earnshaw <rearnsha at arm dot com>
- To: gcc at gcc dot gnu dot org
- Cc: Richard dot Earnshaw at arm dot com
- Date: Mon, 20 May 2002 14:56:00 +0100
- Subject: Re: gcc compile-time performance
- Organization: ARM Ltd.
- Reply-to: Richard dot Earnshaw at arm dot com
Here's another oddity.
Why is predict.c using the target floating-point emulation routines to do
its branch probability calculations? There must be a faster way of doing
this that is good enough for the level of estimation needed here -- the
probabilities are at best approximate.
When profiling a compilation of combine.c (a function with no floating
point code), I was amazed to find that we spend 2.5% of the total
compilation time in earith() and its children.
Surely either native floating-point code, or even some simple fixed-point
code, would be good enough here.