Hi, I haven't figured out the signed multiply yet (maybe I'll get a chance to think about it at home tonight), but this *should* work for unsigned. It's untested as yet. Using MAC saves a couple of instructions compared to bare MPY.
r5:r4 * r8:r9, result in r15:r14:r13:r12 r15: r14: r13: r12 = r5:r4 * r8:r9 = 0 : 0 : r4 * r9 + 0 : r5 * r9 : 0 + 0 : r4 * r8 : 0 + r5 * r8 : 0 : 0 mov r4, &__MPY mov r9, &__OP2 mov &__RESLO, r12 mov &__RESHI, r13 mov r8, &__OP2 mov r5, &__MAC mov r9, &__OP2 add &__RESLO, r13 addc &__RESHI, r14 mov &__SUMEXT, r15 adc r15 mov r5, &__MPY mov r8, &__OP2 add &__RESLO, r14 addc &__RESHI, r15 mvh., David > Fellows, > can anybody send me a code which does multiplication of two longs (32bits) > with result of 64 bits for both signed and unsigned. The HW multiplier must > be used. > > Source arguments are in r5:r4, r8:r9, result in r15:r14:r13:r12 > > > Thanks in advance, > ~d > > > ------------------------------------------------------- > SF.Net email is Sponsored by the Better Software Conference & EXPO > September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices > Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA > Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf > _______________________________________________ > Mspgcc-users mailing list > Mspgcc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/mspgcc-users > > >
