Week 3 - Instruction Set Architectures (Part 1) Flashcards
What is an Instruction Set Architecture (ISA)?
The ISA is the part of a computer’s architecture that defines the set of instructions the processor can execute, including how instructions are formatted and how they operate on data.
What are the three types of instructions in MIPS architecture?
Operate instructions (e.g., arithmetic operations).
Data movement instructions (e.g., load and store).
Control flow instructions (e.g., branches and jumps).
What is the von Neumann model, and what are its five components?
The von Neumann model is a computer architecture that consists of:
Memory
Processing unit
Input
Output
Control unit
What is RISC and how does it differ from CISC?
RISC stands for Reduced Instruction Set Computer, which uses a small set of simple instructions. CISC (Complex Instruction Set Computer) has more complex instructions, such as the Intel x86 architecture.
What is a MIPS register file, and how many registers does it contain?
The MIPS register file contains 32 registers, each with 32 bits. Registers are used to store data temporarily during instruction execution.
How is an instruction represented in MIPS architecture?
MIPS instructions are represented as 32-bit binary words, which are encoded as machine code. The Instruction Set Architecture (ISA) defines the binary format and execution behavior.
What are the three instruction formats in MIPS?
R-format (register)
I-format (immediate)
J-format (jump)
What is an example of an operate instruction in MIPS, and how is it represented?
An example is the add instruction, which adds two registers and stores the result in a third register:
add $s0, $s1, $s2 # $s0 = $s1 + $s2
How are variables mapped to registers in MIPS assembly?
Variables in high-level programming languages are mapped to specific registers in MIPS, allowing for direct manipulation in assembly code.
What does the R-format in MIPS represent, and what are its components?
The R-format is used for register-to-register operations and includes:
op (opcode)
rs (source register 1)
rt (source register 2)
rd (destination register)
shamt (shift amount)
funct (function code)
What is the I-format in MIPS, and when is it used?
The I-format is used for instructions involving immediate values (constants), such as lw (load word) and addi (add immediate).
What is an example of a load word (lw) instruction in MIPS?
The lw instruction loads data from memory into a register. For example:
lw $s3, 8($s0) # $s3 = Memory[$s0 + 8]
How does MIPS branching work with conditional instructions?
MIPS uses instructions like beq (branch if equal) and bne (branch if not equal) to change control flow based on comparisons between registers.
How is an if-else statement implemented in MIPS assembly?
An if-else statement is implemented using conditional branch instructions and jumps:
bne $s3, $s4, else # if ($s3 != $s4) go to else add $s0, $s1, $s2 # if true, execute this j done # jump to done else: sub $s0, $s0, $s3 # if false, execute this done:
What is a for loop in MIPS assembly?
A for loop can be implemented using conditional branches and jumps. Example for summing numbers from 0 to 9:
addi $s1, $zero, 0 # sum = 0
addi $s0, $zero, 0 # i = 0
addi $t0, $zero, 10 # end condition
for: beq $s0, $t0, done # if i == 10, exit loop
add $s1, $s1, $s0 # sum = sum + i
addi $s0, $s0, 1 # i++
j for
done:
