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MIPS Operations/Operands
• “Operation” (instruction) – Produces a value from one or more input values
• “Operand” -Input or Output values for an operation
• MIPS operations
– Arithmetic operations (integer/floating-point) (add, sub,…)
– Logical operations (and, or,…)
– Shift operations (shift a certain number of bits to the left or right)
– Compare operations (do something if one operand is less than another,…)
– Load/stores to transfer data from/to memory
– Branch/jump operations
– System control operations/coprocessor operations
•Question: Check on the green card. What is the mnemonic for a shift
logical left instruction? ___sll_____
• MIPS operands
– General-purpose registers: Question: name 2 of these_____$t0, $s3_____
– Fixed registers, e.g., HI/LO registers
– Memory location
– Immediate value
–Question: we saw this instruction in lecture: addi $t3,$zero,4. $t3 is the
destination. addi is the mnemonic for the instruction. $zero is an operand,
and 4 is an operand. What type of operand is $zero? (pick from the above
list):__Fixed register, since it always contains 0_ What type of operand is
4?__immediate__ What do you think “i” stands for in “addi”?_immediate_
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MIPS Arithmetic
• Arithmetic Type Instruction:
– <op> <rdestination> <rsource1> <rsource2>
• All arithmetic instructions have 3 operands
– Operand order is fixed: destination first
– 32 registers (page 2 of green card)
–Question: What number is $t3?__11_ What number is $s3?__19___
• Examples
– add $t0, $s0, $s2 # $t0 = $s0 + $s2
– sub $s0, $t0, $t1 # $s0 = $t0 – $t1
–Question: In the sub instruction, which register is rd?_$s0_ Which
register is rs?__$t0___ Which register is rt?__$t1___
rd rs rt
rd rs rtrd rs rt
rd rs rt
Operands
