On 2005-04-01, at 23:17, Richard Guenther wrote:
On Apr 1, 2005 11:07 PM, Mark Mitchell <[EMAIL PROTECTED]> wrote:Dale Johannesen wrote:Agree. (And documentation will be written.)
Yay. It sounds like we're definitely on the same page. I think that as
long as we keep the semantics clear, this will be useful functionality.
That's what I assumed. Anything finer than that is insane. :-)
Actually there are cases where it makes sense: you could ask that a particular call be inlined, or a particular loop be unrolled N times.
True. Consider my remark regarding insanity qualified to whole-function
optimizations. :-)
But the question is, do we want all this sort of #pragmas? It would surely better to improve the compilers decisions on applying certain optimizations. As usual, in most of the cases the compiler will be smarter than the user trying to override it (and hereby maybe only working around bugs in a particular compiler release).
Compilers are good. But they still don't think. And they don't have a clue
about the input characteristics and thus affected runtime behavior of the code.
Sometimes you definitively want to switch the optimizers GOALS at the level of a single file. Or in other words: you want to provide additional information about the runtime of the code to the compiler for better optimization decisions.
Like for example optimizing the whole system for size but letting him optimize some well identified hot-spot functions for speed.
