IBM PowerPC 604 User Manual page 262

These subunits handle all of
the
one-cycle arithmetic instructions. Only one subunit in each
SCIU can obtain and execute an instruction at a time.
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Figure &-14. SCIU Block Diagram
The MCIU, which handles all integer multiple-cycle integer insttuctions, consists of a 32-
bit integer multiplier/divider subunit The multiplier supports early exit on 32 x 16-bit
operations. In addition
the
MCIU executes all mfspr and mtspr insttuctions.
6-36
PowerPC 604 RISC Microproceaeor Ueer'e Manual