------- Comment #6 from eric-gcc at omnifarious dot org 2006-03-02 20:25 ------- I'm pleased that I came up with such a difficult test case for the optimizer. I never thought it'd be that hard. :-)
I don't know anything about the internals, but... The compiler has to generate everything down to the fibconst<0> and fibconst<1> specializations anyway. So why can't it memoize and filter the optimization up? Say it generates fibconst<1> and fibconst<2> in order to generate fibconst<3>, then it discovers that fibconst<3> can be optimized to return plain old '3'. It can save that, and then when it comes down again needing fibconst<2> and fibconst<3> in order to generate fibconst<4>, it can see the already optimized version of fibconst<3> and generate an optimized version of fibconst<4> that just returns plain old '5'. Maybe I have things totally wrong and there's no way to do anything like that with the code. Or maybe it would turn out that that way of doing things is so special case that it's not worth bothering with. But, I just wonder if memoizing some sort of optimized version of a function would help with a lot of things. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=14703
