My program was running faster using mcpu=440 but was not giving the awaited results (I should add a display sooner...). I was linking a program build with soft-float setting against libraries using hard-float setting. Sorry for the noise and thanks for your time. Patrice Le vendredi 23 février 2007 à 14:16 +0100, Segher Boessenkool a écrit : > > I'm having trouble trying to find the best > > compiling > > option for amcc440 with fpu. I'm using a genuine > > fedora core 6 ppc distro (gcc4.1.1). It seems that > > using mcpu=440 gives better results than -mcpu=440fp, > > even with floating point code ? What could be wrong on > > > > my platform to give such a result ? > > Dunno. You need to hunt down more details first: > > -- Run a profiler (oprofile, gprof) to pinpoint one > specific (preferably smallish) piece of code that has > a huge slowdown; > -- Look at the generated assembler code for that routine > to see what's up; > -- Try to figure out why that happened, or report back > here. > > > Segher >