EE 3755 Homework 5 Due: TBA (After covering MIPS Note1 and Note2)

 

Estimated time to solve:

Prob.1 40 mins.

Prob.2 30 mins.

Prob.3 20 mins.

Prob.4 10 mins.

Prob.5 40 mins.

Prob.6 30 mins.

Prob.7 10 mins.

Total: 180 mins.

 

Problem 1: Answer the questions without looking anything.(this is practice, so do not use the simulator program although you may check the correctness of your answer)

 

LOOP:

0x400000 add r1,r2,r3

addi r1, r2,0x20

 

beq r0,r0, LOOP

 

(For the problem 1.1)

1.1)Write Machine code for the above 3 instructions.

(Hexadecimal format)

Hint :

opcode for add is 0 and func field is 0x20.

opcode for addi is 8 and think about rt and rs fields.

opcode for beq is 4

What will be the offset value for LOOP.

 

START:

0x400000 J LINE1

nop

LINE1 beq r0,r0,LINE2

add r1,r0,r0

LINE2 nop

(For the problem1.2)

 

1.2)Write Machine code for the above 5 instructions.

(Hexadecimal format)

 

Hint :

opcode for j is 2 .

What will be the offset value for LINE1 and LINE2.

 

 

1.3)Compute this branch target address:

 

0x400000 bne r1, r2,2

 

1.4)compute this branch target address

 

0x40000c bne r1,r2,-2

 

 

 

 

 

 

Problem 2: Briefly explain about three instruction formats for MIPS.

(Less than 20lines.

Your answer should contain at least these following information.

a)      How big is each field at each format?

b)      Field position.

 

 

 

 

 

Problem 3. write the register values after executing following instructions.

 

Loop:

0x1000

Addi r1, r0, 3;

R1=

 

 

 

 

 

Addi r2, r0, 5;

R1=

R2=

 

 

 

 

Sub r3, r1, r2;

R1=

R2=

R3=

 

 

 

Sub r4, r1, r2;

R1=

R2=

R3=

R4=

R31=

 

Beq r3, r0, loop;

 

 

 

 

R31=

 

ori r1, r2, 20;

R1=

R2=

R3=

 

R31=

 

Addi r4, r0, 0x2000;

R1=

R2=

R3=

R4=

R31=

 

jalr r4;

 

R1=

R2=

R3=

R4=

R31=

 

 

 

Problem 4: True(right) or False(wrong) instruction .

T F

4-1) addi $t0,0x1234,$t0

4-2) subi $t0,$t1,0x1234

4-3) jr $0x123456

4-4) j 0x123456789

 

 

Problem 5: Briefly explain about the register usage for procedure call.

(Less than 20 lines, please. your answer at least should contain explanation about v0, a0,t0,s0 registers)

 

 

 

Problem6: What is the MIPS assembly code for the following C code?

//c..

# Reg Usage: j, $8; sum, $9;

for(j = 0, j < 4;++j){

sum = sum + j;

}

 

 

Problem 7: Write real code for the following pseudo code.

 

7.1)li $2, 0x12345678

7.2)mul $2, $3, $4

7.3)nop

7.4)move $1, $2