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Re: Having the -mfused-madd option honored
Just to be sure, have you compiled the program with optimization (such as -O,
-O2, or -O3)? The GCC combiner that builds up complex insns like multiply and
add is only run when optimizing. I happen to have a PowerPC cross compiler
built from a few weeks ago, and it generates fmadd and fmadds instructions if I
use -mcpu=power5 and -mfused-madd.
Yes, I tried again with -O -O2 and -O3. None worked. I had already
figured out that gcc would only trigger fmadd and fmasub as
optimizations. I also removed the options that enforce the C99
compliance, since fmad and fsub break the semantics of the operations
from the rounding point of view.
Thank four your help.