Should -fcross-jumping be part of -O1?

[Scott A Crosby]

On Wed, 3 Dec 2003 11:29:15 +0100 (CET), Gerald Pfeifer <gp@suse.de> writes:

> On Tue, 2 Dec 2003, Gareth McCaughan wrote:
> > There are several different axes along which the kind
> > of code a compiler generates can vary:
> > [...]
> > So, for instance, you could say
> > 
> >     gcc ..... -Ospeed=3 -Ospace=1 -Odebug=0 -Ocompiletime=0
>  
> I'm afraid that would be a QA nightmare.

It could have an internal implementation that is simpler. Even though
the user-visible behavior appears to have many options, the
implementation may have a small number of cases.

The CMUCL Python compiler uses this information is things like:

' when 3 > speed > safety  use approximate type checking'
' when 3 = speed > safety  remove type checking on functions'
' when space >= speed .....'
' Behavior is undefined when more than one paramater is set to 3'
' when speed=3 and compiletime = 0 ......'


Scott