SPE configuration in GCC

[Mark Mitchell]

David Edelsohn wrote:

> 	The rs6000 port now includes a number of architectures and
> architectural features that cannot exist for some target configurations.
> With GCC's genconditions infrastructure, setting the options to constant
> zero allows the patterns to be omitted and the compiler to optimize out
> tests, speeding up the compiler.

I understand.  Certainly, if AIX or Darwin cannot support chip X, then 
there is not really much point in having a compiler for such a system 
support chip X.

But, for some configurations, such as a general-purpose PowerPC cross 
compiler, people would like to have the ability to use all of variants, 
even if that makes the compiler somewhat slower.  What I'm questioning 
is the decision to make the default (in rs6000.h) a limited 
configuration, rather than to move the optimization into appropriate OS 
configuration files.

-- 
Mark Mitchell
CodeSourcery, LLC
mark@codesourcery.com
(916) 791-8304