On Thu, 28 Jul 2005, Steven Rostedt wrote: > I've been playing with different approaches, (still all hot cache > though), and inspecting the generated code. It's not that the gcc > generated code is always better for the normal case. But since it sees > more and everything is not hidden in asm, it can optimise what is being > used, and how it's used. Since you're considering GCC-generated code for ffs(), ffz() and friends, how about trying __builtin_ffs(), __builtin_clz() and __builtin_ctz() as apropriate? Reasonably recent GCC may actually be good enough to use the fastest code depending on the processor submodel selected. Maciej - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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