Download presentation

Presentation is loading. Please wait.

Published bySydni Grant Modified over 3 years ago

1
CPSC 330 Fall 1999 HW #1 Assigned September 1, 1999 Due September 8, 1999 Submit in class Use a word processor (although you may hand-draw answers to Problems 24 and 25) Chapter 2, Heuring and Jordan, Prob: 2, 3, 4, 5, 6, 9, 14, 23, 24, 25

2
2.3 T is a memory location used as a temporary 3-address 2-address 1-address 0-address ADD A,B,C LOAD A,B LDA D PUSH D ADD T,D,E ADD A,C ADD E PUSH E MPY A,A,T LOAD T,D STA T ADD ADD T,E LDA B PUSH C MPY A,T ADD C PUSH B MPY T ADD STA A MPY POP A

3
2.4 Assume that operands and results are stored in memory addresses can be accessed with direct addressing. Also assume that SRC has a multiply instruction, mpy, that uses format 6. ld r0, B ld r1, C add r0, r0, r1 ld r1, D ld r2, E add r1, r1, r2 mpy r0, r0, r1 st r0, A

4
2.5 Assume each instruction fetch requires one memory access Machine Instructions Opnds/Results Total 3-address 3 9 12 2-address 5 13* 18 1-address 7 7 14 0-address 8 5 13 SRC (gen reg) 8 5 13 *ADD A, C takes 3 data accesses: 2 to fetch A and C and one to store A

5
2.6. 3-address: Each instruction has one 8-bit opcode field and three 24-bit memory address fields, so one instruction needs 10 bytes. Three instructions = 30 bytes. 2-address: Each instruction has one 8-bit opcode field and two 24-bit memory address fields. One instruction needs 7 bytes, so five require 35 bytes. 1-address: Each instruction has one 8-bit opcode field and one 24-bit memory address field. One instruction needs 4 bytes, so eight require 32 bytes. 0-address: One arithmetic instruction only requires one 8-bit opcode field. One PUSH/POP instruction requires one 8-bit and one 24-bit memory address field, so three arithmetic instructions require 3 bytes and five PUSH/POP instructions require 20 bytes. Total 23 bytes. SRC: One load/store instruction requires 8-bit opcode field, one 5-bit register number field, and one 24-bit memory address field, so one load/store instruction requires 5 bytes. One arithmetic instruction requires one 8-bit opcode field and three 5-bit register number fields, so one arithmetic instruction requires 3 bytes. Therefore. five load/store instructions and three arithmetic instructions require 5 * 5 + 3 * 3 = 34 bytes.

6
2.9 In a stack machine, an arithmetic instruction only needs an opcode field, while a PUSH/POP instruction needs both opcode and a much longer address field. If all instructions were forced to be the same length, a considerable amount of memory space would be wasted in arithmetic instructions.

7
2.14 a) ld r0, a ; Get value of a la r1, 1 ; Gt constant +1 lar r2, plus ; Set branch target brzr r2, r0 ; Skip next if a=0 neg r1, r1 ; Convert constant to -1 plus: add r0, r0, r1 ; Form a+1 or a-1 st r0, a ; Update a b) la r4, 0 ; Constant 0 la r3, ndigit ; R[3] points to ndigit[i] lar r2, loop ; Branch target addi r1, r4, 0 ; Make R[1], =i, 0 loop: st r4, 0(r3) ; ndigit[i] = 0 addi r3, r3, 4 ; Advance array pointer addi r1, r1, 1 ; i++ addi r0, r1,-10 ; R[0]<0 iff i<10 brmi r2, r0 ; Repeat if i<10

8
2.23 Register Transfer Control signals ------------------ ------------------- a) W <- R[6]+1 R[6]out, Win Y <- W Wout, Yin Z <- R[4] + Y R[4]out, Zin R[3] <- Z Zout, R[3]in b) Y <- R[5] R[5]out, Yin Z <- R[4] + Y R[4], Zin Y <- Z Zout, Yin Z <- R[3] + Y R[3]out, Zin R[2] <- Z Zout, R[2]in

9
2.24 On whiteboard 2.25 On whiteboard

Similar presentations

OK

1 Chapter 10 - Structures, Unions, Bit Manipulations, and Enumerations Outline 10.1Introduction 10.2Structure Definitions 10.3Initializing Structures 10.4Accessing.

1 Chapter 10 - Structures, Unions, Bit Manipulations, and Enumerations Outline 10.1Introduction 10.2Structure Definitions 10.3Initializing Structures 10.4Accessing.

© 2018 SlidePlayer.com Inc.

All rights reserved.

Ads by Google

Ppt on thought leadership Download ppt on wind energy powerpoint Ppt on remote operated spy robot Skimming reading ppt on ipad Ppt on diffusion of solid in liquid Ppt on standing order medication Ppt on computer hardware troubleshooting Ppt on vegetarian and non vegetarian diet Ppt on ministry of corporate affairs Ppt on post abortion care