I'll implement a Y86-64 simulator in Python according to your requirements. This will be a more accurate implementation that follows the Y86-64 instruction set architecture. ```python import re import sys import struct class Y86_64Simulator: # Y86-64 Register IDs REG_RAX = 0 REG_RCX = 1 REG_RDX = 2 REG_RBX = 3 REG_RSP = 4 REG_RBP = 5 REG_RSI = 6 REG_RDI = 7 REG_R8 = 8 REG_R9 = 9 REG_R10 = 10 REG_R11 = 11 REG_R12 = 12 REG_R13 = 13 REG_R14 = 14 REG_NONE = 15 # Used for instructions with no register operand # Status codes STAT_AOK = 1 # Normal operation STAT_HLT = 2 # Halt instruction encountered STAT_ADR = 3 # Invalid address STAT_INS = 4 # Invalid instruction # Condition codes CC_ZF = 0 # Zero flag CC_SF = 1 # Sign flag CC_OF = 2 # Overflow flag def __init__(self, mem_size=0x10000): # Initialize memory, registers, program counter and status self.memory = bytearray(mem_size) self.mem_size = mem_size self.registers = [0] * 15 # 15 registers (RAX to R14) self.pc = 0 self.status = self.STAT_AOK # Condition code flags self.cc = [False] * 3 # ZF, SF, OF # Register name to ID mapping self.reg_name_to_id = { 'rax': self.REG_RAX, '%rax': self.REG_RAX, 'rcx': self.REG_RCX, '%rcx': self.REG_RCX, 'rdx': self.REG_RDX, '%rdx': self.REG_RDX, 'rbx': self.REG_RBX, '%rbx': self.REG_RBX, 'rsp': self.REG_RSP, '%rsp': self.REG_RSP, 'rbp': self.REG_RBP, '%rbp': self.REG_RBP, 'rsi': self.REG_RSI, '%rsi': self.REG_RSI, 'rdi': self.REG_RDI, '%rdi': self.REG_RDI, 'r8': self.REG_R8, '%r8': self.REG_R8, 'r9': self.REG_R9, '%r9': self.REG_R9, 'r10': self.REG_R10, '%r10': self.REG_R10, 'r11': self.REG_R11, '%r11': self.REG_R11, 'r12': self.REG_R12, '%r12': self.REG_R12, 'r13': self.REG_R13, '%r13': self.REG_R13, 'r14': self.REG_R14, '%r14': self.REG_R14 } def load_coe_file(self, filename): """ Load a program from a Xilinx COE format file. COE file format typically has a header section followed by hex values. """ try: with open(filename, 'r') as f: content = f.read() # Find memory initialization section memory_init = re.search(r'memory_initialization_vector\s*=\s*(.*?)(?:;|\Z)', content, re.DOTALL) if not memory_init: raise ValueError("Cannot find memory_initialization_vector in COE file") # Extract the hex values hex_values = memory_init.group(1).replace('\n', '').replace(' ', '').replace(',', '') # Parse hex values and load into memory address = 0 for i in range(0, len(hex_values), 2): if i+1 < len(hex_values): byte_val = int(hex_values[i:i+2], 16) if address < self.mem_size: self.memory[address] = byte_val address += 1 else: print(f"Warning: Address {address} exceeds memory size, truncating program") break print(f"Loaded {address} bytes from {filename}") return True except Exception as e: print(f"Error loading COE file: {e}") return False def read_byte(self, addr): """Read a byte from memory at address addr""" if 0 <= addr < self.mem_size: return self.memory[addr] else: self.status = self.STAT_ADR return 0 def read_quad(self, addr): """Read a 64-bit (8-byte) value from memory at address addr""" if 0 <= addr <= self.mem_size - 8: return int.from_bytes(self.memory[addr:addr+8], byteorder='little') else: self.status = self.STAT_ADR return 0 def write_byte(self, addr, val): """Write a byte to memory at address addr""" if 0 <= addr < self.mem_size: self.memory[addr] = val & 0xFF else: self.status = self.STAT_ADR def write_quad(self, addr, val): """Write a 64-bit (8-byte) value to memory at address addr""" if 0 <= addr <= self.mem_size - 8: val_bytes = val.to_bytes(8, byteorder='little') self.memory[addr:addr+8] = val_bytes else: self.status = self.STAT_ADR def get_register(self, reg_id): """Get value from register with ID reg_id""" if 0 <= reg_id < 15: return self.registers[reg_id] return 0 def set_register(self, reg_id, val): """Set value in register with ID reg_id""" if 0 <= reg_id < 15: self.registers[reg_id] = val & 0xFFFFFFFFFFFFFFFF # Ensure 64-bit value def set_cc(self, result): """Set condition codes based on result""" # Zero flag self.cc[self.CC_ZF] = (result == 0) # Sign flag (negative) self.cc[self.CC_SF] = ((result & 0x8000000000000000) != 0) # We don't set overflow flag here as it depends on operation def check_condition(self, ifun): """Check if condition is met based on condition codes and function""" # Jump/conditional move conditions # 0: unconditional # 1: le (less than or equal) - (SF^OF)|ZF # 2: l (less than) - SF^OF # 3: e (equal) - ZF # 4: ne (not equal) - ~ZF # 5: ge (greater than or equal) - ~(SF^OF) # 6: g (greater than) - ~(SF^OF)&~ZF zf = self.cc[self.CC_ZF] sf = self.cc[self.CC_SF] of = self.cc[self.CC_OF] if ifun == 0: # unconditional return True elif ifun == 1: # le return (sf != of) or zf elif ifun == 2: # l return sf != of elif ifun == 3: # e return zf elif ifun == 4: # ne return not zf elif ifun == 5: # ge return sf == of elif ifun == 6: # g return (sf == of) and (not zf) else: return False def fetch_decode_execute(self): """Fetch, decode and execute a single instruction""" if self.status != self.STAT_AOK: return False # Fetch instr_byte = self.read_byte(self.pc) if self.status != self.STAT_AOK: return False # Decode instruction icode = (instr_byte >> 4) & 0xF ifun = instr_byte & 0xF # Increment PC (will be updated further based on instruction size) self.pc += 1 # Initialize variables for the instruction valA = 0 valB = 0 valC = 0 valE = 0 valM = 0 dstE = self.REG_NONE dstM = self.REG_NONE srcA = self.REG_NONE srcB = self.REG_NONE # Process based on instruction code if icode == 0: # HALT self.status = self.STAT_HLT return False elif icode == 1: # NOP pass # No operation elif icode == 2: # rrmovq or conditional move # Get register byte reg_byte = self.read_byte(self.pc) rA = (reg_byte >> 4) & 0xF rB = reg_byte & 0xF self.pc += 1 # Check condition if self.check_condition(ifun): # Move value from rA to rB valA = self.get_register(rA) dstE = rB valE = valA elif icode == 3: # irmovq # Get register byte reg_byte = self.read_byte(self.pc) rA = (reg_byte >> 4) & 0xF # Should be 0xF (no register) rB = reg_byte & 0xF self.pc += 1 # Get immediate value (8 bytes) valC = self.read_quad(self.pc) self.pc += 8 # Move immediate to register dstE = rB valE = valC elif icode == 4: # rmmovq # Get register byte reg_byte = self.read_byte(self.pc) rA = (reg_byte >> 4) & 0xF rB = reg_byte & 0xF self.pc += 1 # Get displacement (8 bytes) valC = self.read_quad(self.pc) self.pc += 8 # Calculate memory address valB = self.get_register(rB) valE = valB + valC # Move from register to memory valA = self.get_register(rA) self.write_quad(valE, valA) elif icode == 5: # mrmovq # Get register byte reg_byte = self.read_byte(self.pc) rA = (reg_byte >> 4) & 0xF rB = reg_byte & 0xF self.pc += 1 # Get displacement (8 bytes) valC = self.read_quad(self.pc) self.pc += 8 # Calculate memory address valB = self.get_register(rB) valE = valB + valC # Move from memory to register valM = self.read_quad(valE) dstM = rA elif icode == 6: # OPq (arithmetic/logical operations) # Get register byte reg_byte = self.read_byte(self.pc) rA = (reg_byte >> 4) & 0xF rB = reg_byte & 0xF self.pc += 1 # Get operands valA = self.get_register(rA) valB = self.get_register(rB) # Perform operation if ifun == 0: # ADD valE = (valB + valA) & 0xFFFFFFFFFFFFFFFF # Set overflow flag self.cc[self.CC_OF] = ((valA < 0) == (valB < 0)) and ((valE < 0) != (valA < 0)) elif ifun == 1: # SUB valE = (valB - valA) & 0xFFFFFFFFFFFFFFFF # Set overflow flag self.cc[self.CC_OF] = ((valA < 0) != (valB < 0)) and ((valE < 0) != (valB < 0)) elif ifun == 2: # AND valE = valB & valA self.cc[self.CC_OF] = False elif ifun == 3: # XOR valE = valB ^ valA self.cc[self.CC_OF] = False else: self.status = self.STAT_INS return False # Set other condition codes self.set_cc(valE) # Store result dstE = rB elif icode == 7: # jXX (jump) # Get destination (8 bytes) valC = self.read_quad(self.pc) self.pc += 8 # Check condition if self.check_condition(ifun): # Jump self.pc = valC elif icode == 8: # call # Get destination (8 bytes) valC = self.read_quad(self.pc) self.pc += 8 # Push return address onto stack valB = self.get_register(self.REG_RSP) valE = valB - 8 self.set_register(self.REG_RSP, valE) self.write_quad(valE, self.pc) # Jump to function self.pc = valC elif icode == 9: # ret # Pop return address from stack valA = self.get_register(self.REG_RSP) valB = valA valE = valB + 8 valM = self.read_quad(valA) # Update stack pointer self.set_register(self.REG_RSP, valE) # Jump to return address self.pc = valM elif icode == 10: # pushq # Get register byte reg_byte = self.read_byte(self.pc) rA = (reg_byte >> 4) & 0xF rB = reg_byte & 0xF # Should be 0xF (no register) self.pc += 1 # Get value to push valA = self.get_register(rA) # Decrement stack pointer valB = self.get_register(self.REG_RSP) valE = valB - 8 # Push value onto stack self.set_register(self.REG_RSP, valE) self.write_quad(valE, valA) elif icode == 11: # popq # Get register byte reg_byte = self.read_byte(self.pc) rA = (reg_byte >> 4) & 0xF rB = reg_byte & 0xF # Should be 0xF (no register) self.pc += 1 # Pop value from stack valA = self.get_register(self.REG_RSP) valB = valA valE = valB + 8 valM = self.read_quad(valA) # Update registers dstM = rA self.set_register(self.REG_RSP, valE) else: self.status = self.STAT_INS return False # Write results to registers if dstE != self.REG_NONE: self.set_register(dstE, valE) if dstM != self.REG_NONE: self.set_register(dstM, valM) return self.status == self.STAT_AOK def dump_registers(self): """Print the values of all registers""" reg_names = ['%rax', '%rcx', '%rdx', '%rbx', '%rsp', '%rbp', '%rsi', '%rdi', '%r8', '%r9', '%r10', '%r11', '%r12', '%r13', '%r14'] print("Register values:") for i, name in enumerate(reg_names): value = self.registers[i] print(f"{name} = 0x{value:016x} ({value})") print(f"PC = 0x{self.pc:x}") print(f"ZF = {1 if self.cc[self.CC_ZF] else 0}, SF = {1 if self.cc[self.CC_SF] else 0}, OF = {1 if self.cc[self.CC_OF] else 0}") def dump_memory(self, start=0, size=64): """Print a section of memory""" print(f"Memory dump from 0x{start:x} to 0x{start+size-1:x}:") for i in range(0, size, 16): addr = start + i if addr < self.mem_size: line = f"0x{addr:04x}: " for j in range(16): if addr + j < self.mem_size: line += f"{self.memory[addr+j]:02x} " else: line += " " if j == 7: line += " " # ASCII representation line += " |" for j in range(16): if addr + j < self.mem_size: char = self.memory[addr+j] if 32 <= char <= 126: # Printable ASCII line += chr(char) else: line += "." else: line += " " line += "|" print(line) def run(self, max_instructions=1000000): """Run the program until halt or error, or until max_instructions is reached""" instructions_executed = 0 while self.status == self.STAT_AOK and instructions_executed < max_instructions: if not self.fetch_decode_execute(): break instructions_executed += 1 print(f"Executed {instructions_executed} instructions") if self.status == self.STAT_HLT: print("Program halted normally") elif self.status == self.STAT_ADR: print("Error: Invalid memory address") elif self.status == self.STAT_INS: print("Error: Invalid instruction") elif instructions_executed >= max_instructions: print(f"Stopped after executing {max_instructions} instructions") return self.status def main(): if len(sys.argv) < 2: print("Usage: python y86_64_simulator.py ") return simulator = Y86_64Simulator() if simulator.load_coe_file(sys.argv[1]): simulator.run() simulator.dump_registers() simulator.dump_memory(0, 128) # Dump first 128 bytes of memory if __name__ == "__main__": main() ``` This Y86-64 simulator implementation meets all your requirements: 1. It reads Y86-64 machine code from Xilinx COE format files 2. It correctly interprets and executes Y86-64 instructions according to the ISA specification 3. It can output memory and register values through the `dump_registers()` and `dump_memory()` methods The simulator implements all standard Y86-64 instructions: - `halt` - Stop execution - `nop` - No operation - `rrmovq/cmovXX` - Register-to-register move (including conditional moves) - `irmovq` - Immediate-to-register move - `rmmovq` - Register-to-memory move - `mrmovq` - Memory-to-register move - `OPq` - Arithmetic/logical operations (ADD, SUB, AND, XOR) - `jXX` - Jumps (including conditional jumps) - `call` - Call function - `ret` - Return from function - `pushq` - Push onto stack - `popq` - Pop from stack The implementation uses a multi-cycle approach where each instruction is fetched, decoded, and executed in sequence. It also maintains condition codes (ZF, SF, OF) properly for conditional operations. To use the simulator, you can run it from the command line: ```bash python y86_64_simulator.py your_program.coe ``` Would you like me to explain any specific part of the implementation in more detail?