BurritOS/src/simulator/machine.rs

use std::{ops::{Add, Sub}, io::Write};

use crate::simulator::print;

use super::{decode::{Instruction, decode}, interrupt::Interrupt};
use super::global::*;
use std::fs::File;

pub const STACK_REG: usize = 2;

pub const NUM_INT_REGS: usize = 32;
pub const NUM_FP_REGS: usize = 32;

/// doit disparaitre
const MEM_SIZE : usize = 0x500000;

pub trait RegisterNum: Add<Output=Self> + Sub<Output=Self> + PartialEq + Copy {}

impl RegisterNum for i64 {}

impl RegisterNum for f32 {}


#[derive(PartialEq)]
pub struct Register<U: RegisterNum> {
	register: [U; 32]
}

impl<U: RegisterNum> Register<U> {

	pub fn get_reg(&self, position: usize) -> U {
		self.register[position]
	}

}

impl Register<i64> {

	pub fn init() -> Register<i64> {
		Register { 
			register: [0i64; 32]
		}
	}

	pub fn set_reg(&mut self, position: usize, value: i64) {
		if position != 0 {
			self.register[position] = value;
		} else {
			// Panic ou rien ? (dans le doute pour le moment panic)
			// unreachable!("You can't write to zero register")
		}
	}

}

impl Register<f32> {

	pub fn init() -> Register<f32> {
		Register { 
			register: [0f32; 32]
		}
	}

	pub fn set_reg(&mut self, position: usize, value: f32) {
		self.register[position] = value;
	}

}

#[derive(PartialEq)]
pub struct Machine {
	pub pc : u64,
	pub sp: usize,
	pub int_reg : Register<i64>,
	pub fp_reg : Register<f32>,
	pub main_memory : Vec<u8>,
	pub shiftmask : [u64 ; 64],
	pub registers_trace : String, // for tests
	pub interrupt: Interrupt
	// futur taille à calculer int memSize = g_cfg->NumPhysPages * g_cfg->PageSize;
	//creer une struct cfg(configuration) qui s'initialise avec valeur dans un fichier cfg
}


impl Machine {

	pub fn init_machine() -> Machine {	
		let mut shiftmask : [u64 ; 64] = [0 ; 64];
		let mut value : u64 = 0xffffffff;

		value = (value << 32) + value;
		for item in &mut shiftmask {
			*item = value;
			value >>= 1;
		}

		let mut ret = Machine {
			pc : 0,
			sp: 0,
			int_reg : Register::<i64>::init(),
			fp_reg : Register::<f32>::init(),
			main_memory : vec![0_u8; MEM_SIZE],
			shiftmask,
			interrupt: Interrupt::new(),
			registers_trace : String::from("")
		};

		ret.int_reg.set_reg(10, -1);
		ret
	}

	/// Read from main memory of the machine
	///
	/// `panic!` when size is not 1, 2, 4 or 8
	/// 
	/// ### Parameters
	///
	/// - **machine** which contains the main memory
	/// - **size** the number of bytes to read (1, 2, 4, 8)
	/// - **address** in the memory to read
	pub fn read_memory(machine : &mut Machine, size : i32, address : usize) -> u64 {
		if ![1, 2, 4, 8].contains(&size) {
			panic!("ERROR read_memory : wrong size parameter {size}, must be (1, 2, 4 or 8)");
		}

		let mut ret: u64 = 0;
		for i in 0..size {
			ret <<= 8;
			ret += machine.main_memory[address + i as usize] as u64;
		}
		ret
	}

	/// Write to the main memory of the machine
	/// 
	/// `panic!` when size is not 1, 2, 4 or 8
	/// 
	/// ### Parameters
	/// 
	/// - **machine** contains the memory
	/// - **size** the number of bytes to write (1, 2, 4 or 8)
	/// - **address** the address to write to
	/// - **value** data to be written
	pub fn write_memory(machine: &mut Machine, size: i32, address: usize, value: u64) {
		if ![1, 2, 4, 8].contains(&size) {
			panic!("ERROR write_memory: WRONG `size` PARAMETER ({size}), must be 1, 2, 4 or 8")
		}
		for i in 0..size as usize {
			let inv_i = size as usize - i - 1;
			machine.main_memory[address + i] = ((value & 0xff << (8 * inv_i)) >> (inv_i * 8)) as u8;
		}
	}

	/// Write the contains of the main memory of the machine
	/// in a file called burritos_memory.txt
	/// 
	/// ### Parameters
	/// 
	///  - **machine** contains the memory
	pub fn _extract_memory(machine: &mut Machine){
		let file_path = "burritos_memory.txt";
		let write_to_file = |path| -> std::io::Result<File> {
			let mut file = File::create(path)?;
			file.write_all(&machine.main_memory)?;
			Ok(file)
		};
		match write_to_file(file_path) {
			Err(e) => eprintln!("Failed to write memory to file: {}", e),
			Ok(_) => println!("Memory extracted to {}", file_path)
		};
	}

	pub fn print_machine_status(machine: &mut Machine) {
		println!("######### Machine status #########");
		for i in (0..32).step_by(3) {
			print!(">{0: <4} : {1:<16x} ", print::REG_X[i], machine.int_reg.get_reg(i));
			print!(">{0: <4} : {1:<16x} ", print::REG_X[i+1], machine.int_reg.get_reg(i+1));
			if i+2 < 32 {
				print!(">{0: <4} : {1:<16x} ", print::REG_X[i+2], machine.int_reg.get_reg(i+2));
			}
			println!();
		}
		println!("________________SP________________");
		let sp_index = machine.int_reg.get_reg(2);
		for i in 0..5 {
			println!("SP+{:<2} : {:16x}", i*8, Self::read_memory(machine, 8, (sp_index + i*8) as usize));
		}		
		println!("##################################");
	}

	pub fn string_registers(machine: &mut Machine) -> String {
		let mut s = String::from("");
		for i in 0..32 {
			s.push_str(format!("{} ", machine.int_reg.get_reg(i)).as_str());
		}
		s
	}

	/// Execute the instructions table of a machine putted in param
	/// 
	/// ### Parameters
	/// 
	/// - **machine** which contains a table of instructions
	pub fn run(machine : &mut Machine){
		while Machine::one_instruction(machine) == 0 {}
		println!("trace : \n{}", machine.registers_trace);
	}

	/// execute the current instruction
	/// 
	/// ### Parameters
	/// 
	/// - **machine** which contains a table of instructions and a pc to the actual instruction
	pub fn one_instruction(machine :&mut Machine) -> i32 {
	
		let unsigned_reg1 : u64;
		let unsigned_reg2 : u64;
		let long_result : i128;
		 
		 /*__int128 longResult;
  		int32_t local_data_a, local_data_b;
  		int64_t localLongResult;
  		uint32_t local_data_aUnsigned, local_data_bUnsigned;
  		int32_t localResult;
  		float localFloat;
  		uint64_t value;*/
	
		if machine.main_memory.len() <= machine.pc as usize {
			panic!("ERROR : number max of instructions rushed");
		}
		let mut val: [u8; 4] = [0; 4];
		for (i, mut _item) in val.iter_mut().enumerate() {
			_item = &mut machine.main_memory[machine.pc as usize + i];
		}

		let val = u32::from_be_bytes(val) as u64;
		let inst : Instruction = decode(val);
		Self::print_machine_status(machine);
		println!("executing instruction : {:016x} at pc {:x}", val, machine.pc);
		println!("{}", print::print(decode(val), machine.pc as i32));
		let trace = Self::string_registers(machine);
		machine.registers_trace.push_str(format!("{}\n", trace).as_str());
		
		machine.pc += 4;
		
		match inst.opcode {
			RISCV_LUI => {
				machine.int_reg.set_reg(inst.rd as usize, inst.imm31_12 as i64);
			},
			RISCV_AUIPC => {
				machine.int_reg.set_reg(inst.rd as usize,machine.pc as i64 - 4 + inst.imm31_12 as i64);
			},
			RISCV_JAL => {
				machine.int_reg.set_reg(inst.rd as usize, machine.pc as i64);
				machine.pc = (machine.pc as i64 + inst.imm21_1_signed as i64 - 4) as u64;
			},
			RISCV_JALR => {
				let tmp = machine.pc;
				machine.pc = (machine.int_reg.get_reg(inst.rs1 as usize) + inst.imm12_I_signed as i64) as u64 & 0xfffffffe;
				machine.int_reg.set_reg(inst.rd as usize, tmp as i64);
			},

			//******************************************************************************************
  			// Treatment for: BRANCH INSTRUCTIONS
			RISCV_BR => {
				match inst.funct3 {
					RISCV_BR_BEQ => {
						if machine.int_reg.get_reg(inst.rs1 as usize) == machine.int_reg.get_reg(inst.rs2 as usize) {
							machine.pc = (machine.pc as i64 + inst.imm13_signed as i64 - 4) as u64;
						}
					},
					RISCV_BR_BNE => {
						if machine.int_reg.get_reg(inst.rs1 as usize) != machine.int_reg.get_reg(inst.rs2 as usize) {
							machine.pc = (machine.pc as i64 + inst.imm13_signed as i64 - 4) as u64;
						}
					},
					RISCV_BR_BLT => {
						if machine.int_reg.get_reg(inst.rs1 as usize) < machine.int_reg.get_reg(inst.rs2 as usize) {
							machine.pc = (machine.pc as i64 + inst.imm13_signed as i64 - 4) as u64;
						}
					},
					RISCV_BR_BGE => {
						if machine.int_reg.get_reg(inst.rs1 as usize) >= machine.int_reg.get_reg(inst.rs2 as usize) {
							machine.pc = (machine.pc as i64 + inst.imm13_signed as i64 - 4) as u64;
						}
					},
					RISCV_BR_BLTU => {
						if machine.int_reg.get_reg(inst.rs1 as usize) < machine.int_reg.get_reg(inst.rs2 as usize) {
							machine.pc = (machine.pc as i64 + inst.imm13_signed as i64 - 4) as u64;
						}
					},
					RISCV_BR_BGEU => {
						if machine.int_reg.get_reg(inst.rs1 as usize) >= machine.int_reg.get_reg(inst.rs2 as usize) {
							machine.pc = (machine.pc as i64 + inst.imm13_signed as i64 - 4) as u64;
						}
					},
					_ => {
						panic!("In BR switch case, this should never happen... Instr was {}", inst.value);
					}
				}
			},

			//******************************************************************************************
    		// Treatment for: LOAD INSTRUCTIONS
			RISCV_LD => {
				match inst.funct3 {
					RISCV_LD_LB | RISCV_LD_LBU => {
						let tmp = Self::read_memory(machine, 1, (machine.int_reg.get_reg(inst.rs1 as usize) + inst.imm12_I_signed as i64) as usize) as i64;
						machine.int_reg.set_reg(inst.rd as usize, tmp);
					},
					RISCV_LD_LH | RISCV_LD_LHU => {
						let tmp = Self::read_memory(machine, 2, (machine.int_reg.get_reg(inst.rs1 as usize) + inst.imm12_I_signed as i64) as usize) as i64;
						machine.int_reg.set_reg(inst.rd as usize, tmp);
					},
					RISCV_LD_LW | RISCV_LD_LWU => {
						let tmp = Self::read_memory(machine, 4, (machine.int_reg.get_reg(inst.rs1 as usize) + inst.imm12_I_signed as i64) as usize) as i64;
						machine.int_reg.set_reg(inst.rd as usize, tmp);
					},
					RISCV_LD_LD => {
						let tmp = Self::read_memory(machine, 8, (machine.int_reg.get_reg(inst.rs1 as usize) + inst.imm12_I_signed as i64) as usize) as i64;
						machine.int_reg.set_reg(inst.rd as usize, tmp);
					},
					_ => {
						panic!("In LD switch case, this should never happen... Instr was {}", inst.value);
					}
				}
			},
			// store instructions
			RISCV_ST => {
				match inst.funct3 {
					RISCV_ST_STB => {
						Self::write_memory(machine, 1, (machine.int_reg.get_reg(inst.rs1 as usize) + inst.imm12_S_signed as i64) as usize, machine.int_reg.get_reg(inst.rs2 as usize) as u64);
					},
					RISCV_ST_STH => {
						Self::write_memory(machine, 2, (machine.int_reg.get_reg(inst.rs1 as usize) + inst.imm12_S_signed as i64) as usize, machine.int_reg.get_reg(inst.rs2 as usize) as u64);
					},
					RISCV_ST_STW => {
						Self::write_memory(machine, 4, (machine.int_reg.get_reg(inst.rs1 as usize) + inst.imm12_S_signed as i64) as usize, machine.int_reg.get_reg(inst.rs2 as usize) as u64);
					},
					RISCV_ST_STD => {
						Self::write_memory(machine, 8, (machine.int_reg.get_reg(inst.rs1 as usize) + inst.imm12_S_signed as i64) as usize, machine.int_reg.get_reg(inst.rs2 as usize) as u64);
					},
					_ => {
						panic!("In ST switch case, this should never happen... Instr was {}", inst.value);
					}
				}
			}
			//******************************************************************************************
    		// Treatment for: OPI INSTRUCTIONS
			RISCV_OPI => {
				match inst.funct3 {
					RISCV_OPI_ADDI => {
						machine.int_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) + inst.imm12_I_signed as i64);
					},
					RISCV_OPI_SLTI => {
						machine.int_reg.set_reg(inst.rd as usize, (machine.int_reg.get_reg(inst.rs1 as usize) < inst.imm12_I_signed as i64) as i64);
					},
					RISCV_OPI_XORI => {
						machine.int_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) ^ inst.imm12_I_signed as i64);
					},
					RISCV_OPI_ORI => {
						machine.int_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) | inst.imm12_I_signed as i64);
					},
					RISCV_OPI_ANDI => {
						machine.int_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) & inst.imm12_I_signed as i64);
					},
					RISCV_OPI_SLLI => {
						machine.int_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) << inst.shamt);
					},
					RISCV_OPI_SRI => {
						if inst.funct7_smaller == RISCV_OPI_SRI_SRLI {
							machine.int_reg.set_reg(inst.rd as usize, (machine.int_reg.get_reg(inst.rs1 as usize) >> inst.shamt) & machine.shiftmask[inst.shamt as usize] as i64);
						} else { // SRAI
							machine.int_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) >> inst.shamt);
						}
					}
					_ => { panic!("In OPI switch case, this should never happen... Instr was %x\n {}", inst.value); }
				}
			},
			
			RISCV_OP => {
				if inst.funct7 == 1 {
					match inst.funct3 {
						RISCV_OP_M_MUL => {
							long_result = (machine.int_reg.get_reg(inst.rs1 as usize) * machine.int_reg.get_reg(inst.rs2 as usize)) as i128;
							machine.int_reg.set_reg(inst.rd as usize, (long_result & 0xffffffffffffffff) as i64);
						},
						RISCV_OP_M_MULH => {
							long_result = (machine.int_reg.get_reg(inst.rs1 as usize) * machine.int_reg.get_reg(inst.rs2 as usize)) as i128;
							machine.int_reg.set_reg(inst.rd as usize, ((long_result >> 64) & 0xffffffffffffffff) as i64);
						},
						RISCV_OP_M_MULHSU => {
							unsigned_reg2 = machine.int_reg.get_reg(inst.rs2 as usize) as u64;
            				long_result   = (machine.int_reg.get_reg(inst.rs1 as usize) as u64 * unsigned_reg2) as i128;
            				machine.int_reg.set_reg(inst.rd as usize, ((long_result >> 64) & 0xffffffffffffffff) as i64);
						},
						// VOIR CE QUE FAIT EXACTEMENT CE TRUC , PK on converve
						/*
						* VOIR SI LES CAST machine.int_reg[....] = i128*u64 as u32 FAUSSE RESULTAT (suit pas la logique du code c++)
						* WHAT DA HECK
						*/
						RISCV_OP_M_MULHU => {
							unsigned_reg1 = machine.int_reg.get_reg(inst.rs1 as usize) as u64;
            						unsigned_reg2 = machine.int_reg.get_reg(inst.rs2 as usize) as u64;
            						long_result   = (unsigned_reg1 * unsigned_reg2) as i128;
	   						machine.int_reg.set_reg(inst.rd as usize, ((long_result >> 64) & 0xffffffffffffffff) as i64);
						},
						RISCV_OP_M_DIV => {
							machine.int_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) / machine.int_reg.get_reg(inst.rs2 as usize));
						}
						_ => {
							panic!("RISCV_OP : funct7 = 1 (Multiplication) :: Error\n");
						}
					}
				} else {
					match inst.funct3 {
						RISCV_OP_ADD => {
							if inst.funct7 == RISCV_OP_ADD_ADD {
								machine.int_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) + machine.int_reg.get_reg(inst.rs2 as usize));
							} else {
								machine.int_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) - machine.int_reg.get_reg(inst.rs2 as usize));
							}
						},
						RISCV_OP_SLL => {
							machine.int_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) << (machine.int_reg.get_reg(inst.rs2 as usize) & 0x3f));
						},
						RISCV_OP_SLT => {
							if machine.int_reg.get_reg(inst.rs1 as usize) < machine.int_reg.get_reg(inst.rs2 as usize) {
								machine.int_reg.set_reg(inst.rd as usize, 1);
							} else {
								machine.int_reg.set_reg(inst.rd as usize, 0);
							}
						},
						RISCV_OP_SLTU => {
							unsigned_reg1 = machine.int_reg.get_reg(inst.rs1 as usize) as u64;
							unsigned_reg2 = machine.int_reg.get_reg(inst.rs2 as usize) as u64;
							if unsigned_reg1 < unsigned_reg2 {
								machine.int_reg.set_reg(inst.rd as usize, 1);
							} else {
								machine.int_reg.set_reg(inst.rd as usize, 0);
							}
						},
						RISCV_OP_XOR => {
							machine.int_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) ^ machine.int_reg.get_reg(inst.rs2 as usize));
						},
						RISCV_OP_SR => {
						// RISCV_OP_SR_SRL inaccessible
							machine.int_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) >> machine.int_reg.get_reg(inst.rs2 as usize));
						},
						RISCV_OP_OR => {
							machine.int_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) | machine.int_reg.get_reg(inst.rs2 as usize));
						},
						RISCV_OP_AND => {
							machine.int_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) & machine.int_reg.get_reg(inst.rs2 as usize));
						},
						_ => {
							panic!("RISCV_OP undefined case\n");
						}
					}//LA
				}
			},
			//******************************************************************************************
			// Treatment for OPIW INSTRUCTIONS
			RISCV_OPIW => {
				let local_data = machine.int_reg.get_reg(inst.rs1 as usize);
				match inst.funct3 {
					RISCV_OPIW_ADDIW => {
						let result = local_data + inst.imm12_I_signed as i64;
						machine.int_reg.set_reg(inst.rd as usize, result);
					},
					RISCV_OPIW_SLLIW => {
						let result = local_data << inst.shamt;
						machine.int_reg.set_reg(inst.rd as usize, result);
					},
					RISCV_OPIW_SRW => {
						let result = if inst.funct7 == RISCV_OPIW_SRW_SRLIW {
							(local_data >> inst.shamt) & machine.shiftmask[32 + inst.shamt as usize] as i64
						} else { // SRAIW
							local_data >> inst.shamt
						};
						machine.int_reg.set_reg(inst.rd as usize, result);
					},
					_ => {
						panic!("In OPI switch case, this should never happen... Instr was {}\n", inst.value);
					}
				}
			},
			//******************************************************************************************
    		// Treatment for: OPW INSTRUCTIONS
			RISCV_OPW => {
				if inst.funct7 == 1 { // rv64m
					let local_data_a = machine.int_reg.get_reg(inst.rs1 as usize) & 0xffffffff;
					let local_data_b = machine.int_reg.get_reg(inst.rs2 as usize) & 0xffffffff;
					let local_data_a_unsigned = machine.int_reg.get_reg(inst.rs1 as usize) & 0xffffffff;
					let local_data_b_unsigned = machine.int_reg.get_reg(inst.rs2 as usize) & 0xffffffff;

					// Match case for multiplication operations (in standard extension RV32M)
					match inst.funct3 {
						RISCV_OPW_M_MULW => {
							machine.int_reg.set_reg(inst.rd as usize, local_data_a * local_data_b);
						},
						RISCV_OPW_M_DIVW => {
							machine.int_reg.set_reg(inst.rd as usize, local_data_a / local_data_b);
						},
						RISCV_OPW_M_DIVUW => {
							machine.int_reg.set_reg(inst.rd as usize, local_data_a_unsigned / local_data_b_unsigned);
						},
						RISCV_OPW_M_REMW => {
							machine.int_reg.set_reg(inst.rd as usize, local_data_a % local_data_b);
						},
						RISCV_OPW_M_REMUW => {
							machine.int_reg.set_reg(inst.rd as usize, local_data_a_unsigned % local_data_b_unsigned);
						},
						_ => {
							panic!("this instruction ({}) doesn't exists", inst.value);
						}
					}
				} else { // others rv64 OPW operations
					let local_dataa = machine.int_reg.get_reg(inst.rs1 as usize) & 0xffffffff;
					let local_datab = machine.int_reg.get_reg(inst.rs2 as usize) & 0xffffffff;

					// Match case for base OP operation
					match inst.funct3 {
						RISCV_OPW_ADDSUBW => {
							if inst.funct7 == RISCV_OPW_ADDSUBW_ADDW {
								machine.int_reg.set_reg(inst.rd as usize, local_dataa + local_datab);
							} else { // SUBW
								machine.int_reg.set_reg(inst.rd as usize, local_dataa - local_datab);
							}
						},
						RISCV_OPW_SLLW => {
							machine.int_reg.set_reg(inst.rd as usize, local_dataa << (local_datab & 0x1f));
						},
						RISCV_OPW_SRW => {
							if inst.funct7 == RISCV_OPW_SRW_SRLW {
								machine.int_reg.set_reg(inst.rd as usize, local_dataa >> (local_datab & 0x1f) & machine.shiftmask[32 + local_datab as usize] as i64);
							} else { // SRAW
								machine.int_reg.set_reg(inst.rd as usize, local_dataa >> (local_datab & 0x1f));
							}
						},
						_ => {
							panic!("this instruction ({}) doesn't exists", inst.value);
						}
					}
				}
			},
			//******************************************************************************************
    		// Treatment for: Simple floating point extension
			RISCV_FP => {
				match inst.funct7 {
					RISCV_FP_ADD => {
						machine.fp_reg.set_reg(inst.rd as usize, machine.fp_reg.get_reg(inst.rs1 as usize) + machine.fp_reg.get_reg(inst.rs2 as usize));
					},
					RISCV_FP_SUB => {
						machine.fp_reg.set_reg(inst.rd as usize, machine.fp_reg.get_reg(inst.rs1 as usize) - machine.fp_reg.get_reg(inst.rs2 as usize));
					},
					RISCV_FP_MUL => {
						machine.fp_reg.set_reg(inst.rd as usize, machine.fp_reg.get_reg(inst.rs1 as usize) * machine.fp_reg.get_reg(inst.rs2 as usize));
					},
					RISCV_FP_DIV => {
						machine.fp_reg.set_reg(inst.rd as usize, machine.fp_reg.get_reg(inst.rs1 as usize) / machine.fp_reg.get_reg(inst.rs2 as usize));
					},
					RISCV_FP_SQRT => {
						machine.fp_reg.set_reg(inst.rd as usize, machine.fp_reg.get_reg(inst.rs1 as usize).sqrt());
					},
					RISCV_FP_FSGN => {
						let local_float = machine.fp_reg.get_reg(inst.rs1 as usize);
						match inst.funct3 {
							RISCV_FP_FSGN_J => {
								if machine.fp_reg.get_reg(inst.rs2 as usize) < 0f32 {
									machine.fp_reg.set_reg(inst.rd as usize, -local_float);
								} else {
									machine.fp_reg.set_reg(inst.rd as usize, local_float);
								}
							}
							RISCV_FP_FSGN_JN => {
								if machine.fp_reg.get_reg(inst.rs2 as usize) < 0f32 {
									machine.fp_reg.set_reg(inst.rd as usize, local_float);
								} else {
									machine.fp_reg.set_reg(inst.rd as usize, -local_float);
								}
							}
							RISCV_FP_FSGN_JX => {
								if (machine.fp_reg.get_reg(inst.rs2 as usize) < 0.0 && machine.fp_reg.get_reg(inst.rs1 as usize) >= 0.0) || (machine.fp_reg.get_reg(inst.rs2 as usize) >= 0.0 && machine.fp_reg.get_reg(inst.rs1 as usize) < 0.0) {
									machine.fp_reg.set_reg(inst.rd as usize, -local_float);
								} else {
									machine.fp_reg.set_reg(inst.rd as usize, local_float);
								}
							}
							_ => {
								panic!("this instruction ({}) doesn't exists", inst.value);
							}
						}
					},
					RISCV_FP_MINMAX => {
						let r1 = machine.fp_reg.get_reg(inst.rs1 as usize);
						let r2 = machine.fp_reg.get_reg(inst.rs2 as usize);
						match inst.funct3 {
							RISCV_FP_MINMAX_MIN => {
								machine.fp_reg.set_reg(inst.rd as usize, if r1 < r2 {r1} else {r2});
							},
							RISCV_FP_MINMAX_MAX => {
								machine.fp_reg.set_reg(inst.rd as usize, if r1 > r2 {r1} else {r2});
							},
							_ => {
								panic!("this instruction ({}) doesn't exists", inst.value);
							}
						}
					},
					RISCV_FP_FCVTW => {
						if inst.rs2 == RISCV_FP_FCVTW_W {
							machine.int_reg.set_reg(inst.rd as usize, machine.fp_reg.get_reg(inst.rs1 as usize) as i64);
						} else {
							machine.int_reg.set_reg(inst.rd as usize, (machine.fp_reg.get_reg(inst.rs1 as usize) as u64) as i64);
						}
					},
					RISCV_FP_FCVTS => {
						if inst.rs2 == RISCV_FP_FCVTS_W {
							machine.fp_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) as f32);
						} else {
							machine.fp_reg.set_reg(inst.rd as usize, (machine.int_reg.get_reg(inst.rs1 as usize) as u32) as f32);
						}
					},
					RISCV_FP_FMVW => {
						machine.fp_reg.set_reg(inst.rd as usize, machine.int_reg.get_reg(inst.rs1 as usize) as f32);
					},
					RISCV_FP_FMVXFCLASS => {
						if inst.funct3 == RISCV_FP_FMVXFCLASS_FMVX {
							machine.int_reg.set_reg(inst.rd as usize, machine.fp_reg.get_reg(inst.rs1 as usize) as i64);
						} else {
							panic!("Fclass instruction is not handled in riscv simulator");
						}
					},
					RISCV_FP_FCMP => {
						match inst.funct3 {
							RISCV_FP_FCMP_FEQ => {
								machine.int_reg.set_reg(inst.rd as usize, (machine.fp_reg.get_reg(inst.rs1 as usize) == machine.fp_reg.get_reg(inst.rs2 as usize)) as i64);
							},
							RISCV_FP_FCMP_FLT => {
								machine.int_reg.set_reg(inst.rd as usize, (machine.fp_reg.get_reg(inst.rs1 as usize) < machine.fp_reg.get_reg(inst.rs2 as usize)) as i64);
							},
							RISCV_FP_FCMP_FLE => {
								machine.int_reg.set_reg(inst.rd as usize, (machine.fp_reg.get_reg(inst.rs1 as usize) <= machine.fp_reg.get_reg(inst.rs2 as usize)) as i64);
							},
							_ => {
								panic!("this instruction ({}) doesn't exists", inst.value);
							}
						}
					},
					_ => {
						panic!("this instruction ({}) doesn't exists", inst.value);
					}
				}
			}
			RISCV_SYSTEM => {
				// temporary return value to stop the loop of run 
				// before we can use system call 
				return 1;
			}
			_ => { panic!("{:x} opcode non géré pc : {:x}", inst.opcode, machine.pc)},
		}

		0

	}

	/// print memory FOR DEBUG
	/// 
	/// "@"adresse [16 bytes]
	pub fn _print_memory(machine : &mut Machine, from: usize, to: usize) {
		for i in from..to {
			if i%16 == 0 {
				print!("\n@{:04x} ", i);
			}
			print!("{:02x}", machine.main_memory[i]);
		}
		println!();
	}

	pub fn read_int_register(&self, index: usize) -> i64 {
		self.int_reg.get_reg(index)
	}

	pub fn read_fp_register(&self, index: usize) -> f32 {
		self.fp_reg.get_reg(index)
	}

	pub fn write_int_register(&mut self, index: usize, value: i64) {
		self.int_reg.set_reg(index, value);
	}
	
	pub fn write_fp_register(&mut self, index: usize, value: f32) {
		self.fp_reg.set_reg(index, value);
	}
}

#[cfg(test)]
mod test {
    use std::fs;

    use crate::simulator::{machine::Machine, mem_cmp};

	#[test]
	fn test_init_machine() {
		let _ = Machine::init_machine();
	}

	#[test]
	fn test_read_memory() {
		let mut m = Machine::init_machine();
    	m.main_memory[4] = 43;
    	m.main_memory[5] = 150;
		assert_eq!((43 << 8) + 150, Machine::read_memory(&mut m, 2, 4));
	}

	#[test]
	fn test_write_memory() {
		let mut m = Machine::init_machine();
		Machine::write_memory(&mut m, 2, 6, (43 << 8) + 150);
		assert_eq!(43, m.main_memory[6]);
		assert_eq!(150, m.main_memory[7]);
		Machine::write_memory(&mut m, 4, 8, (52 << 24) + (20 << 16) + (43 << 8) + 150);
		assert_eq!(52, m.main_memory[8]);
		assert_eq!(20, m.main_memory[9]);
		assert_eq!(43, m.main_memory[10]);
		assert_eq!(150, m.main_memory[11]);
	}

	#[test]
	fn test_comp() {
		let mut m = Machine::init_machine();
		let path_before = "memoryComp.txt".to_string();
		let path_after = "memoryCompEnd.txt".to_string();
		let memory_before = mem_cmp::MemChecker::from(&path_before).unwrap();
		let memory_after = mem_cmp::MemChecker::from(&path_after).unwrap();
		mem_cmp::MemChecker::fill_memory_from_mem_checker(&memory_before, &mut m);
		Machine::run(&mut m);

		let path_trace = "memoryCompTrace.txt".to_string();
		let expected_trace = fs::read_to_string(path_trace).unwrap();

		assert!(mem_cmp::MemChecker::compare_machine_memory(&memory_after, &m));
		assert!(expected_trace.contains(m.registers_trace.as_str()));
	}

	#[test]
	fn test_div() {
		let mut m = Machine::init_machine();
		let path_before = "memoryDiv.txt";
		let path_after = "memoryDivEnd.txt";
		let memory_before = mem_cmp::MemChecker::from(path_before).unwrap();
		let memory_after = mem_cmp::MemChecker::from(path_after).unwrap();
		mem_cmp::MemChecker::fill_memory_from_mem_checker(&memory_before, &mut m);
		Machine::run(&mut m);

		let path_trace = "memoryDivTrace.txt".to_string();
		let expected_trace = fs::read_to_string(path_trace).unwrap();

		assert!(mem_cmp::MemChecker::compare_machine_memory(&memory_after, &m));
		assert!(expected_trace.contains(m.registers_trace.as_str()));
	}

	#[test]
	fn test_if() {
		let mut m = Machine::init_machine();
		let path_before = "memoryIf.txt".to_string();
		let path_after = "memoryIfEnd.txt".to_string();
		let memory_before = mem_cmp::MemChecker::from(&path_before).unwrap();
		let memory_after = mem_cmp::MemChecker::from(&path_after).unwrap();
		mem_cmp::MemChecker::fill_memory_from_mem_checker(&memory_before, &mut m);
		Machine::run(&mut m);

		let path_trace = "memoryIfTrace.txt".to_string();
		let expected_trace = fs::read_to_string(path_trace).unwrap();

		assert!(mem_cmp::MemChecker::compare_machine_memory(&memory_after, &m));
		assert!(expected_trace.contains(m.registers_trace.as_str()));
	}

	#[test]
	fn test_jump() {
		let mut m = Machine::init_machine();
		let path_before = "memoryJump.txt".to_string();
		let path_after = "memoryJumpEnd.txt".to_string();
		let memory_before = mem_cmp::MemChecker::from(&path_before).unwrap();
		let memory_after = mem_cmp::MemChecker::from(&path_after).unwrap();
		mem_cmp::MemChecker::fill_memory_from_mem_checker(&memory_before, &mut m);
		Machine::run(&mut m);

		let path_trace = "memoryJumpTrace.txt".to_string();
		let expected_trace = fs::read_to_string(path_trace).unwrap();

		assert!(mem_cmp::MemChecker::compare_machine_memory(&memory_after, &m));
		assert!(expected_trace.contains(m.registers_trace.as_str()));
	}

	#[test]
	fn test_mul() {
		let mut m = Machine::init_machine();
		let path_before = "memoryMul.txt".to_string();
		let path_after = "memoryMulEnd.txt".to_string();
		let memory_before = mem_cmp::MemChecker::from(&path_before).unwrap();
		let memory_after = mem_cmp::MemChecker::from(&path_after).unwrap();
		mem_cmp::MemChecker::fill_memory_from_mem_checker(&memory_before, &mut m);
		Machine::run(&mut m);

		let path_trace = "memoryMulTrace.txt".to_string();
		let expected_trace = fs::read_to_string(path_trace).unwrap();

		assert!(mem_cmp::MemChecker::compare_machine_memory(&memory_after, &m));
		assert!(expected_trace.contains(m.registers_trace.as_str()));
	}

	#[test]
	fn test_ret() {
		let mut m = Machine::init_machine();
		let path_before = "memoryRet.txt".to_string();
		let path_after = "memoryRetEnd.txt".to_string();
		let memory_before = mem_cmp::MemChecker::from(&path_before).unwrap();
		let memory_after = mem_cmp::MemChecker::from(&path_after).unwrap();
		mem_cmp::MemChecker::fill_memory_from_mem_checker(&memory_before, &mut m);
		Machine::run(&mut m);

		let path_trace = "memoryRetTrace.txt".to_string();
		let expected_trace = fs::read_to_string(path_trace).unwrap();

		assert!(mem_cmp::MemChecker::compare_machine_memory(&memory_after, &m));
		assert!(expected_trace.contains(m.registers_trace.as_str()));
	}

	#[test]
	fn test_sub() {
		let mut m = Machine::init_machine();
		let path_before = "memorySub.txt".to_string();
		let path_after = "memorySubEnd.txt".to_string();
		let memory_before = mem_cmp::MemChecker::from(&path_before).unwrap();
		let memory_after = mem_cmp::MemChecker::from(&path_after).unwrap();
		mem_cmp::MemChecker::fill_memory_from_mem_checker(&memory_before, &mut m);
		Machine::run(&mut m);

		let path_trace = "memorySubTrace.txt".to_string();
		let expected_trace = fs::read_to_string(path_trace).unwrap();

		assert!(mem_cmp::MemChecker::compare_machine_memory(&memory_after, &m));
		assert!(expected_trace.contains(m.registers_trace.as_str()));
	}

	#[test]
	fn test_switch() {
		let mut m = Machine::init_machine();
		let path_before = "memorySwitch.txt".to_string();
		let path_after = "memorySwitchEnd.txt".to_string();
		let memory_before = mem_cmp::MemChecker::from(&path_before).unwrap();
		let memory_after = mem_cmp::MemChecker::from(&path_after).unwrap();
		mem_cmp::MemChecker::fill_memory_from_mem_checker(&memory_before, &mut m);
		Machine::run(&mut m);

		let path_trace = "memorySwitchTrace.txt".to_string();
		let expected_trace = fs::read_to_string(path_trace).unwrap();

		assert!(mem_cmp::MemChecker::compare_machine_memory(&memory_after, &m));
		assert!(expected_trace.contains(m.registers_trace.as_str()));
	}
}