Chapter 4. The Processor Customization
54
Figure 4.7: The execution completion stage
After the initialization the processor starts execution and the whole process lasts another
44 cycles. Each load instruction lasts five cycles since the processor stalls to avoid
hazards. Eight load instructions makes up to 40 cycles plus another 4 for the register
write of the ”and” instruction. Figure
displays the completion of the whole process
at clock cycle 54 where the ”register input” module gives the correct result.
As expected the register file, after the execution, contains three values:
• ”0100101001010100110111111111111000101001010010011001001010010101”
is in the address ”00001”
• ”1101010101010111001010101011000001010101000000000010010101010100”
is contained in the address ”00010”
• ”0100000001010100000010101011000000000001000000000000000000010100”
the ”and” result is contained in address ”00011”. The address ”00000” was not
used since it is hardwired to zero.