QUESTION 20:
Would this instruction have worked as well?
or $25,$0,$12 # move s into target register
sll $12,$12,21 # left shift s by 21 places or $25,$25,$12 # move s into target register
The low-order bit of the pattern for $s is in bit position
0 (of register $12). It must be moved to position 21 of
the instruction.
Next, the or copies it into the instruction
being assembled.
The or works like this:
| 31....26 | 25...21 | 20...16 | 15.............................0 | |||||||||||||||||||||||||||||
| Register $12 (before) | 000000 | 01001 | 00000 | 0000 0000 0000 0000 | ||||||||||||||||||||||||||||
| Register $25 (before) | 001101 | 00000 | 00000 | 0000 0000 0000 0000 | ||||||||||||||||||||||||||||
| Register $25 (after) | 001101 | 01001 | 00000 | 0000 0000 0000 0000 | ||||||||||||||||||||||||||||
Would this instruction have worked as well?
or $25,$0,$12 # move s into target register