Optimizing calls to GSL functions

[Brian Gough]

At Sat, 9 Jun 2007 04:25:55 +0200,
Tommy Nordgren wrote:
> Are there any way, when using the GNU Compiler Collection, to make
> the compiler optimize expressions where the same function call
> occurs more than once.  (Same function, same parameters) GCC does
> this for standard C functions such as cos and sin, when passed -O3
> or -Os -fgcse I'm interested in this, because most special functions
> computed by GSL are probably more expensive to compute than the
> basic transcendental functions, and in general you can get many
> common subexpressions when generating C code from symbol math
> programs.

__attribute__ ((pure), see "Function attributes" in the GCC manual for
details.

-- 
Brian Gough