add rd, rs, rt # signed addition of integers
# GPR[rd] <-- GPR[rs] + GPR[rt]
addi rt, rs, imm16 # signed addition with 16-bit immediate
# GPR[rt] <-- GPR[rs] + imm16
addiu rt, rs, imm16 # unsigned addition with 16-bit immediate
# GPR[rt] <-- GPR[rs] + imm16
and rd, rs, rt # bitwise logical AND
# GPR[rd] <-- GPR[rs] AND GPR[rt]
andi rt, rs, imm16 # bitwise logical AND with 16-bit immediate
# GPR[rd] <-- GPR[rs] AND imm16
mul rd, rs, rt # signed multiplication of integers
# GPR[rd] <-- GPR[rs] * GPR[rt]
nop # no operation
# executed as: sll $zero, $zero, 0
nor rd, rs, rt # bitwise logical NOR
# GPR[rd] <-- !(GPR[rs] OR GPR[rt])
or rd, rs, rt # bitwise logical OR
# GPR[rd] <-- GPR[rs] OR GPR[rt]
ori rt, rs, imm16 # bitwise logical OR with 16-bit immediate
# GPR[rd] <-- GPR[rs] OR imm16
sll rd, rt, sa # logical shift left a fixed number of bits
# GPR[rd] <-- GPR[rs] <<l sa
slt rd, rs, rt # set register to result of comparison
# GPR[rd] <-- (GPR[rs] < GPR[rt] ? 0 : 1)
CS 2506 Computer Organization II C Programming 5: Simple MIPS Assembler
Version 5.00 This is a purely individual assignment! 3
slti rs, rt, imm16 # set register to result of comparison
# GPR[rd] <-- (GPR[rs] < imm16 ? 0 : 1)
sra rd, rt, sa # arithmetic shift right a fixed number of bits
# GPR[rd] <-- GPR[rs] >>a sa
sub rd, rs, rt # signed subtraction of integers
# GPR[rd] <-- GPR[rs] - GPR[rt]
Your assembler must support the following basic control-of-flow instructions:
beq rs, rt, offset # conditional branch if rs == rt
# PC <-- (rs == rt ? PC + 4 + offset <<l 2)
# : PC + 4)
blez rs, offset # conditional branch if rs <= 0
# PC <-- (rs <= 0 ? PC + 4 + offset <<l 2)
# : PC + 4)
bltz rs, offset # conditional branch if rs < 0
# PC <-- (rs < 0 ? PC + 4 + offset <<l 2)
# : PC + 4)
bne rs, rt, offset # conditional branch if rs != rt
# PC <-- (rs != rt ? PC + 4 + offset <<l 2)
# : PC + 4)
j target # unconditional branch
# PC <-- ( (PC+4)(31:28) || (target <<l 2))
syscall # invoke exception handler, which examines $v0
# to determine appropriate action; if it returns,
# returns to the succeeding instruction; see the
# MIPS32 Instruction Reference for format