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Old 29 October 2018, 17:00   #590
Megol
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Join Date: May 2014
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Quote:
Originally Posted by grond View Post
Well, ldm, stm, mul and divs all do well with microcode. Not much but not nothing either. Thanks God or rather Sophie Wilson that they did use microcode and not insist on the programmer using a bunch of primitive instructions to implement these instructions in macrocode...
DIVS? ARM added integer division after 2010 IIRC, don't think microcode is involved.

Quote:
I think MIPS and also the earlier SPARC required the programmer to use a sequence of shift-add/subtract instructions in order to make multiplications and divisions.
MIPS used an ugly hack for integer multiplication as it didn't fit into the ordinary pipeline but it was there. SPARC used the FPU IIRC which wasn't too unusual at the time or even now (for integer division).
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