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On Mon, Dec 02, 2002 at 10:49:57AM -0500, Peter Barada wrote: > >(Incidently, if you are compiling with -msoft-float, I don't > >expect that using doubles will "increase performance", as > >you'll double the amount of work the processor has to do...) > > It all depends on the hardware implementation of the FPU. If the FPU > can only operate in double precision, then to properly model single > precision operations requires rounding instructions to be added after > every operation to force the final result to appear as if it was > calculated in single precision. This can indeed slow it down. Interesting.. But that has to be expected every time you use hardware in a manner that it wasn't indended for (same story, it's not easier to play at 8KHz on a DSP that only supports 24KHz...). However, I was talking about code compiled with -msoft-float... where arguably all operations are performed with many cycles by the non-floating-point-enable CPU... Then it should always be slower to use double than single? (if double is indeed bigger than single, as pointed out in Kai's other posting on the subject). /Y ------ Want more information? See the CrossGCC FAQ, http://www.objsw.com/CrossGCC/ Want to unsubscribe? Send a note to crossgcc-unsubscribe@sources.redhat.com
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