> Yes, but you must be careful. These macros will be interpreted differently > depending on whether their arguments are signed or unsigned, so you must > ensure their assembly replacements are appropriate. Sorry to bother you again, but maybe you can try to create repleacements for C functions with use of umul_ppmm code? I'm afraid I'm not so skilled and only one mistake - you get noise or no sound in the output file. :P It looks for me that mp3 decoder uses only signed arguments. I will re-done the benchmark on the 68060 with all functions asm optimized. BTW. I compared the output wav files from original version and inlined of FFmpeg and everything is ok - files are identical. Regards