x86-emulator

Developing an x86 Processor Instruction Emulator

Goal

Goal of this programming assignment is to get a first-hand experience about the nature of real-world complex instruction set computers (CISC) and their instruction decoding process.

Task

Write a program (preferably in C/C++) that emulates the instruction decoding of an x86 processor.

Build

$ make

C++ 11 is required.

Run

$ ./emulator.out [path to input file]

eg:- $ ./emulator.out sample_inputs/instruction_sequence/p0.in

1. Run Example Programs

Sample input programs are in sample_inputs/instruction_sequence/

Input programs	Output programs
p0.in	p0.in.out
p1.in	p1.in.out
p2.in	p2.in.out
p3.in	p3.in.out
p4.in	p4.in.out
p5.in	p5.in.out
p6.in	p6.in.out

eg:- $ ./emulator.out sample_inputs/instruction_sequence/p0.in

2. Run Example Opcodes

Sample inputs for single opcodes are in sample_inputs/[opcode]/.in

Sample outputs for the corresponding single opcodes are in sample_inputs/[opcode]/.out.txt

eg:- $ ./emulator.out sample_inputs/add/add00.in

File and Folders

• Makefile - Scipts to build the program

• main.cpp - Main driver program

• memory.hpp - Declarations of the Memory module

• memory.cpp - Implementation of the memory moduel

• register.hpp - Declarations of the Register Bank

• register.cpp - Implementation of the Register Bank

• reader.hpp - Declarations of the Input Reader module

• reader.cpp - Implementation of the Input Reader moduel

• modmr.hpp - Declarations of the ModR/M decode module

• modmr.cpp - Implementation of the ModR/M docode moduel

• sib.hpp - Declarations of the SIB decode module

• sib.cpp - Implementation of the SIB decode moduel

• utility_flag_set.hpp - Declarations of the utility functions to set flags

• utility_flag_set.cpp - Implementation of the utility functions to set flags

• utility_functions.hpp - Declarations of the utility functions

• utility_functions.cpp - Implementation of the utility functions

• util.hpp - Declaration of utility data structures

• opcode_extension.hpp - Declarations of the opcode extension handling functions

• opcode_extension.cpp - Implementation of the opcode extension handling functions

• opcodes/opcodes.hpp - Header file include of supported opcodes

• opcodes/[ opcode ].hpp - Declaration of the decode and excution functions of the respective opcode

• opcodes/[ opcode ].cpp - Implementaion of the decode and excution functions of the respective opcode

• sample_inputs/[ opcode ]/ [ Input File Name ].in - Sample inputs for specific opcodes

• sample_inputs/[ opcode ]/ [ Input File Name ].out.txt - Corresponding outputs of the sample opcode inputs

• sample_inputs/instruction_sequence/ [ Input File Name ].in - Sample input programs

• sample_inputs/instruction_sequence/ [ Input File Name ].out.txt - Corresponding outputs of the sample input programs

Resources

• Intel® 64 and IA-32 Architectures Developer's Manual: Vol. 2

Contributers

• Damika Gamlath
• Gayal Dassanayake