Instruction Sets: Characteristics and Functions thuộc "Bài giảng Computer Organization and Architecture: Chapter 10" sẽ đi sâu giới thiệu tới các bạn một số thông tin cơ bản về What is an instruction set; Elements of an Instruction; Where have all the Operands gone;. | William Stallings Computer Organization and Architecture 6th Edition Chapter 10 Instruction Sets: Characteristics and Functions What is an instruction set? The complete collection of instructions that are understood by a CPU Machine Code Binary Usually represented by assembly codes 2 Elements of an Instruction Operation code (Op code) Do this Source Operand reference To this Result Operand reference Put the answer here Next Instruction Reference When you have done that, do this. 3 Where have all the Operands gone? Long time passing . (If you don’t understand, you’re too young!) Main memory (or virtual memory or cache) CPU register I/O device 4 Instruction Cycle State Diagram Instruction Representation In machine code each instruction has a unique bit pattern For human consumption (well, programmers anyway) a symbolic representation is used . ADD, SUB, LOAD Operands can also be represented in this way ADD A,B 5 Simple Instruction Format Instruction Types Data processing Data . | William Stallings Computer Organization and Architecture 6th Edition Chapter 10 Instruction Sets: Characteristics and Functions What is an instruction set? The complete collection of instructions that are understood by a CPU Machine Code Binary Usually represented by assembly codes 2 Elements of an Instruction Operation code (Op code) Do this Source Operand reference To this Result Operand reference Put the answer here Next Instruction Reference When you have done that, do this. 3 Where have all the Operands gone? Long time passing . (If you don’t understand, you’re too young!) Main memory (or virtual memory or cache) CPU register I/O device 4 Instruction Cycle State Diagram Instruction Representation In machine code each instruction has a unique bit pattern For human consumption (well, programmers anyway) a symbolic representation is used . ADD, SUB, LOAD Operands can also be represented in this way ADD A,B 5 Simple Instruction Format Instruction Types Data processing Data storage (main memory) Data movement (I/O) Program flow control 6 Number of Addresses (a) 3 addresses Operand 1, Operand 2, Result a = b + c; May be a forth - next instruction (usually implicit) Not common Needs very long words to hold everything 7 Number of Addresses (b) 2 addresses One address doubles as operand and result a = a + b Reduces length of instruction Requires some extra work Temporary storage to hold some results 8 Number of Addresses (c) 1 address Implicit second address Usually a register (accumulator) Common on early machines 9 Number of Addresses (d) 0 (zero) addresses All addresses implicit Uses a stack . push a push b add pop c c = a + b 10 How Many Addresses More addresses More complex (powerful?) instructions More registers Inter-register operations are quicker Fewer instructions per program Fewer addresses Less complex (powerful?) instructions More instructions per program Faster fetch/execution of instructions 11 Design Decisions (1) Operation repertoire How many
