COMBINATION PC/LINE PREFETCH ADDRESS ADDER
Original Publication Date: 1991-Jul-01
Included in the Prior Art Database: 2001-Dec-11
The pc section of the 68040 integer unit calculates the instruction program counter (PC) and instruction prefetch address (PFA). The PC is a word address (31-bits) and the prefetch address is a quad-word address (29-bits). In each cycle, the pc unit calculates a new PC based on the length of the dispatched instruction and PFA based on length of the dispatched instruction and the number of words left in the 128- bit, 8-word prefetch buffer, (PB).