you are to write an emulator for the y86 instruction set using the C programming language. The y86 architecture is a very small subset of the x86 instruction set which performs many of the essential functions of x86 and which is useful for teaching and research purposes. I've included a number of documents about y86 which has all the essential details about the architecture, including a chapter from the textbook for which the instruction set was developed.
Your emulator should read in a text file that contains only the opcode bytes representing the program. The file will be plain ASCII text file representing the bytes in either lower or uppercase (expect to see "30f4b8" or "30F4B8"). You can assume the file contains no spaces or line breaks, only characters representing the program's bytes. Your emulator should verify the input from one of my test programs is valid. Use the test program in Chapter 4 of CS:APP (attached) to create a test program of your own. Some others can be found online (the authors of that book have a number of them). Load the program into memory starting from the first byte of memory (memory address 0). Your emulator should run the program completely and output the final state of the registers, the program counter, and the condition flags.
The y86 architecture contains a memory region containing 2000 bytes, 8 program registers, three condition codes (OF, ZF, and SF), a program counter. Each read and write to memory or to the registers writes out a full 4-byte word. The 8 registers, are the same as the 32-bit x86 architecture (see the register numbering in the attached slides). Programs that run on your emulator will typically implement their own stack to make function calls, which will be set up by pointing the stack pointer and base pointer (EBP and ESP) to the location where the stack should begin (somewhere in higher-addressed memory). The stack will be used for the pushl, popl, call, and ret instructions which implement procedure / function calls.
You will need to implement logic to fetch, decode, execute, update_memory, update_registers, and update_program_counter. All of the instructions you will need to be able to decode, fetch, and execute for are listed below. See the attached materials for the specific format and opcodes of each instruction. In cases in which there is a conflict between the specification in the attached materials (they have a few differences), use the CS:APP chapter 4 as the deciding reference. Opcodes for each instruction are variable-length from 1 to 6 bytes. Ensure you complete your own work and comment your code well. All other previous project submission instructions apply. Have fun!