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Re: [MiNT] MiNTLib for ColdFire : DONE !


Ok, tricky. MVS and MVZ could be trapped and emulated, but the MAC instructions screw things up.. Didier solved the latter by using an unused TRAP instruction. Is this something which could be added to the kernel as well? It does make it slightly easier to write code for both systems, since I woudn't have to check which CPU I'm running on.

-- PeP

4 jun 2009 kl. 16.21 skrev Vincent Rivière:

Yes, this is true.
But currently, GCC does generate MAC instructions, so the ColdFire executables will not be incompatible because of that.

For example, there is no add.b and add.w on ColdFire. The data must be fetched into a register, then add.l can be used. The new mvs and mvz instructions can be used to fetch a byte or a word, then fill the remaining part of the target register to be suitable for add.l.