Compilation performance comparison of 3.5.0 and TreeSSA trees on MICO sources as requested in: [tree-ssa] Merge status 2004-05-03

[Joe Buck]

On Wed, May 05, 2004 at 08:09:26PM +0200, Laurent GUERBY wrote:
> A -Og flag that would do all optimizations that
> 
> - don't take too much time and memory ressources
> - still allow perfect debugability
> - tend to generate smalled code and debug information
> 
> Would be just perfect :). 

Make it the default.

> I would fix a rule to allow up to 5-10%
> more compile time and memory at -Og than -O0
> and zero gdb breakage.

NO!!!!

The purpose of doing some optimization is to make -O0 *faster*.  We've
already got a 20% speed degradation any you want to allow 5% *more*?

(Pardon the shouting).

Applying some low-cost optimizations for space will make the
compiler+assembler+linker run *faster*.