#------------------------------------------------------------------------------ # A simple diagnostic that will execute most instructions # at least once and them dump the register file so that you # can see it on the memory output bus #------------------------------------------------------------------------------ # Try modifying R0 main: addi $0, $0, 1 # R0 had better still be 0 #------------------------------------------------------------------------------ # misc ALU tests #------------------------------------------------------------------------------ # addsub sub $24, $0, $0 # r24 = 0 addi $2, $0, 1 # r2=1 addi $3, $0, -1 # r3=-1 add $4, $3, $2 # r4=0 (no exceptions) andi $5, $3, 255 # r5=255=0x000000FF addu $6, $5, $2 # r6=256=0x00000100 addiu $7, $6, 768 # r7=1024=0x00000400 subu $8, $7, $6 # r8=768=0x00000300 # logic ori $9, $0, 21845 # r9=21845=0x00005555 or $9, $9, $0 # r9=21845=0x00005555 =unchanged and $9, $9, $3 # r9=21845=0x00005555 =unchanged nor $10, $9, $0 # r10=-21846=0xFFFFAAAA xor $11, $10, $10 # r11=0 =0x00000000 xori $12, $9, 65522 # r12=0x0000AAA7 # shift sll $13, $9, 8 # r13=5592320=0x00555500 sllv $14, $2, $2 # r14=2 =0x00000002 srl $15, $10, 5 # r15=134217045=0x07fffD55 srlv $16, $9, $2 # r16=10922=0x00002AAA mult $15, $16 # {hi,lo} = 0x7fffd55 * 0x2aaa mfhi $15 # r15 = 0x00000155 mflo $16 # r16 = 0x4f8e2c72 div $16, $15 # hi = 0x4f8e2c72 mod 0x155, lo = 0x4f8e2c72 / 0x155 mfhi $15 # r15 = 0x000000f7 mflo $16 # r16 = 0x003bb98f mthi $5 # use hi and lo to swap registers r5 and r6 mtlo $6 mfhi $6 # r6 = =0x000000FF mflo $5 # r5 = 0x000000100 sra $17, $3, 4 # r17=-1=0xFFFFFFFF srav $18, $9, $14 # r18=5461=0x00001555 slt $19, $9, $9 # r19=0=0x00000000 slt $20, $5, $6 # r20=0=0x00000000 sltu $21, $4, $3 # r21=1=0x00000001 sltiu $22, $3, 0 # r22=0=0x00000000 #------------------------------------------------------------------------------ # test the jump instructions #------------------------------------------------------------------------------ addi $23,$0,0 # set register 23 to zero j jumpok addi $23,$0,-1 # -1 in r23 means jump failed jumpok: addi $24,$0,0 # initialize register 24 to zero jal jalok # this is taken w/$31 = PC addi $24,$24,1 # should not come here after jal, but will after jalr below j out# jalok: addi $24,$0,100 # re-init $24 to 100 jalr $31 # now jump back 3 instructions out: # will test jr below #------------------------------------------------------------------------------ # test branch instructions # for these test r2 = 1, r3 = -1 (see above) #------------------------------------------------------------------------------ beq $3,$3 taken # taken branch: PC moves ahead by 8 stuck: j stuck # don't execute this instruction taken: beq $3, $2, stuck # no take branch (failures get stuck) bne $3,$2 taken1 # taken branch: PC moves ahead by 8 stuck1: j stuck1 # don't execute this instruction taken1: bne $3, $3, stuck1 # no take branch (failures get stuck) bltz $3, taken2 # taken branch: PC moves ahead by 8 stuck2: j stuck2 # don't execute this instruction taken2: bltz $2, stuck1 # no take branch (failures get stuk) blez $0, taken3 # taken branch: PC moves ahead by 8 stuck3: j stuck3 # don't execute this instruction taken3: blez $2, stuck3 # no take branch (failures get stuck) blez $3, taken4 # taken branch: PC moves ahead by 8 stuck4: j stuck4 # don't execute this instruction taken4: blez $2, stuck4 # no take branch (failures get stuck) bltzal $3, taken5 # taken branch: PC moves ahead by 8 stuck5: j stuck6 # don't execute this instruction taken5: bltzal $2, stuck5 # no take branch (failures get stuck); add $25,$0,$31 # link address in r25 bgtz $2, taken6 # taken branch: PC moves ahead by 8 stuck6: j stuck6 # don't execute this instruction taken6: bgtz $3, stuck6 # no take branch (failures get stuck) bgez $0, taken7 # taken branch: PC moves ahead by 8 stuck7: j stuck7 # don't execute this instruction taken7: bgez $3, stuck7 # no take branch (failures get stuck) bgez $2, taken8 # taken branch: PC moves ahead by 8 stuck8: j stuck8 # don't execute this instruction taken8: bgez $3, stuck8 # no take branch (failures get stuck) bgezal $2, taken9 # taken branch: PC moves ahead by 8 stuck9: j stuck9 # don't execute this instruction taken9: bgezal $3, stuck9 # no take branch (failures get stuck); add $26,$0,$31 # link address in r26 #------------------------------------------------------------------------------ # test load/store #------------------------------------------------------------------------------ sw $17,4($0) sh $17,10($0) sb $17,11($0) lw $25,4($0) # r25 = 0xffffffff lhu $26,4($0) # r26 = 0x0000ffff lbu $27,4($0) # r27 = 0x000000ff lh $28,4($0) # r28 = 0xffffffff lb $29,4($0) # r29 = 0xffffffff sub $30,$0,$0 # r30 = 0 lui $1, 2 # r1 = 0x00020000 #------------------------------------------------------------------------------ # this is your output.. #------------------------------------------------------------------------------ sw $1, 0($30) addi $30,$30,4 sw $2, 0($30) addi $30,$30,4 sw $3, 0($30) addi $30,$30,4 sw $4, 0($30) addi $30,$30,4 sw $5, 0($30) addi $30,$30,4 sw $6, 0($30) addi $30,$30,4 sw $7, 0($30) addi $30,$30,4 sw $8, 0($30) addi $30,$30,4 sw $9, 0($30) addi $30,$30,4 sw $10, 0($30) addi $30,$30,4 sw $11, 0($30) addi $30,$30,4 sw $12, 0($30) addi $30,$30,4 sw $13, 0($30) addi $30,$30,4 sw $14, 0($30) addi $30,$30,4 sw $15, 0($30) addi $30,$30,4 sw $16, 0($30) addi $30,$30,4 sw $17, 0($30) addi $30,$30,4 sw $18, 0($30) addi $30,$30,4 sw $19, 0($30) addi $30,$30,4 sw $20, 0($30) addi $30,$30,4 sw $21, 0($30) addi $30,$30,4 sw $22, 0($30) addi $30,$30,4 sw $23, 0($30) addi $30,$30,4 sw $24, 0($30) addi $30,$30,4 sw $25, 0($30) addi $30,$30,4 sw $26, 0($30) addi $30,$30,4 sw $27, 0($30) addi $30,$30,4 sw $28, 0($30) addi $30,$30,4 sw $29, 0($30) addi $30,$30,4 add $31,$0,$0 jr $31 .data str: .asciiz "simple test\n" #------------------------------------------------------------------------------ # end of simple test #------------------------------------------------------------------------------