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forked from Rativel/BurritOS
Files
BurritOS/src/machine.rs
2022-11-21 13:21:48 +01:00

275 lines
9.1 KiB
Rust

use crate::decode::*;
use crate::print::*;
// doit disparaitre
const MEM_SIZE : usize= 4096;
pub struct Machine {
pub pc : u32,
pub int_reg : [u32 ; 32],
pub instructions : [u32 ; 100],
pub main_memory : [u8 ; MEM_SIZE],
pub shiftmask : [u32 ; 32]
// 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 : [u32 ; 32] = [0 ; 32];
let mut value : u32 = 0xffff;
value = (value << 16) + value;
for i in 0..32 {
shiftmask[i] = value;
value = value >> 1;
}
Machine {
pc : 0,
instructions : [0 ; 100],
int_reg : [0 ; 32],
main_memory : [0 ; MEM_SIZE],
shiftmask : shiftmask
}
}
/*
execute the instructions table of a machine putted in param
@param machine which contains a table of instructions
*/
pub fn run(machine : Machine){
let mut m = machine;
loop{
Machine::one_instruction(&mut m);
}
}
/*
execute the current instruction
@param machine which contains a table of instructions and a pc to the actual instruction
*/
pub fn one_instruction(machine :&mut Machine) {
let mut unsigned_reg1 : u64 = 0;
let mut unsigned_reg2 : u64 = 0;
let mut long_result : i128 = 0;
/*__int128 longResult;
int32_t localDataa, localDatab;
int64_t localLongResult;
uint32_t localDataaUnsigned, localDatabUnsigned;
int32_t localResult;
float localFloat;
uint64_t value;*/
if machine.instructions.len() <= machine.pc as usize {
println!("ERROR : number max of instructions rushed");
return ;
}
let inst : Instruction = decode(machine.instructions[machine.pc as usize]);
machine.pc += 4;
match inst.opcode {
RISCV_LUI => {
machine.int_reg[inst.rd as usize] = inst.imm31_12;
},
//******************************************************************************************
// Treatment for: OPI INSTRUCTIONS
RISCV_OPI => {
match inst.funct3 {
RISCV_OPI_ADDI => {
machine.int_reg[inst.rd as usize] = machine.int_reg[inst.rs1 as usize] + inst.imm12_I_signed as u32;
},
RISCV_OPI_SLTI => {
machine.int_reg[inst.rd as usize] =
if machine.int_reg[inst.rs1 as usize] < inst.imm12_I_signed as u32 { 1 } else { 0 };
},
RISCV_OPI_XORI => {
machine.int_reg[inst.rd as usize] = machine.int_reg[inst.rs1 as usize] ^ inst.imm12_I_signed as u32;
},
RISCV_OPI_ORI => {
machine.int_reg[inst.rd as usize] = machine.int_reg[inst.rs1 as usize] | inst.imm12_I_signed as u32;
},
RISCV_OPI_ANDI => {
machine.int_reg[inst.rd as usize] = machine.int_reg[inst.rs1 as usize] & inst.imm12_I_signed as u32;
},
RISCV_OPI_SLLI => {
machine.int_reg[inst.rd as usize] = machine.int_reg[inst.rs1 as usize] << inst.shamt;
},
RISCV_OPI_SRI => {
if inst.funct7_smaller == RISCV_OPI_SRI_SRLI {
machine.int_reg[inst.rd as usize] = (machine.int_reg[inst.rs1 as usize] >> inst.shamt) & machine.shiftmask[inst.shamt as usize];
} else { // SRAI
machine.int_reg[inst.rd as usize] = (machine.int_reg[inst.rs1 as usize] >> inst.shamt);
}
}
_ => { println!("{} inconnu", inst.funct3); }
}
},
RISCV_JAL => {
machine.int_reg[inst.rd as usize] = machine.pc;
machine.pc = machine.pc - 4 + (inst.imm21_1_signed as u32);
},
RISCV_OP => {
if(inst.funct7 == 1){
match inst.funct3 {
RISCV_OP_M_MUL => {
long_result = (machine.int_reg[inst.rs1 as usize] * machine.int_reg[inst.rs2 as usize]) as i128;
machine.int_reg[inst.rd as usize] = (long_result & 0xffffffffffffffff) as u32;
},
RISCV_OP_M_MULH => {
long_result = (machine.int_reg[inst.rs1 as usize] * machine.int_reg[inst.rs2 as usize]) as i128;
},
RISCV_OP_M_MULHSU => {
unsigned_reg2 = machine.int_reg[inst.rs2 as usize] as u64;
long_result = (machine.int_reg[inst.rs1 as usize] as u64 * unsigned_reg2) as i128;
machine.int_reg[inst.rd as usize] = ((long_result >> 64) & 0xffffffffffffffff) as u32;
},
// 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[inst.rs1 as usize] as u64;
unsigned_reg2 = machine.int_reg[inst.rs2 as usize] as u64;
long_result = (unsigned_reg1 * unsigned_reg2) as i128;
machine.int_reg[inst.rd as usize] = ((long_result >> 64) & 0xffffffffffffffff) as u32;
},
RISCV_OP_M_DIV => {
machine.int_reg[inst.rd as usize] = (machine.int_reg[inst.rs1 as usize] / machine.int_reg[inst.rs2 as usize]);
}
_ => {
println!("RISCV_OP : funct7 = 1 (Multiplication) :: Error\n");
}
}
} else {
match inst.funct3 {
RISCV_OP_ADD => {
// RISCV_OP_ADD_ADD inaccessible
/*if (inst.funct7 == RISCV_OP_ADD_ADD) {
machine.int_reg[inst.rd as usize] = machine.int_reg[inst.rs1 as usize] + machine.int_reg[inst.rs2 as usize];*/
machine.int_reg[inst.rd as usize] = machine.int_reg[inst.rs1 as usize] - machine.int_reg[inst.rs2 as usize];
//}
},
RISCV_OP_SLL => {
machine.int_reg[inst.rd as usize] = machine.int_reg[inst.rs1 as usize] << (machine.int_reg[inst.rs2 as usize] & 0x3f);
},
RISCV_OP_SLT => {
if machine.int_reg[inst.rs1 as usize] < machine.int_reg[inst.rs2 as usize] {
machine.int_reg[inst.rd as usize] = 1;
} else {
machine.int_reg[inst.rd as usize] = 0;
}
},
RISCV_OP_SLTU => {
unsigned_reg1 = machine.int_reg[inst.rs1 as usize] as u64;
unsigned_reg2 = machine.int_reg[inst.rs2 as usize] as u64;
if unsigned_reg1 < unsigned_reg2 {
machine.int_reg[inst.rd as usize] = 1;
} else {
machine.int_reg[inst.rd as usize] = 0;
}
},
RISCV_OP_XOR => {
machine.int_reg[inst.rd as usize] = machine.int_reg[inst.rs1 as usize] ^ machine.int_reg[inst.rs2 as usize];
},
RISCV_OP_SR => {
// RISCV_OP_SR_SRL inaccessible
machine.int_reg[inst.rd as usize] = machine.int_reg[inst.rs1 as usize] >> (machine.int_reg[inst.rs2 as usize] & 0x3f);
},
RISCV_OP_OR => {
machine.int_reg[inst.rd as usize] = machine.int_reg[inst.rs1 as usize] | machine.int_reg[inst.rs2 as usize];
},
RISCV_OP_AND => {
machine.int_reg[inst.rd as usize] = machine.int_reg[inst.rs1 as usize] & machine.int_reg[inst.rs2 as usize];
},
_ => {
println!("RISCV_OP undefined case\n");
}
}//LA
}
},
//******************************************************************************************
// Treatment for: OPW INSTRUCTIONS
RISCV_OPW => {
if inst.funct7 == 1 {
let localDataa = machine.int_reg[inst.rs1 as usize] & 0xffffffff;
let localDatab = machine.int_reg[inst.rs2 as usize] & 0xffffffff;
let localDataaUnsigned = machine.int_reg[inst.rs1 as usize] & 0xffffffff;
let localDatabUnsigned = machine.int_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[inst.rd as usize] = localDataa * localDatab;
},
RISCV_OPW_M_DIVW => {
machine.int_reg[inst.rd as usize] = localDataa / localDatab;
},
RISCV_OPW_M_DIVUW => {
machine.int_reg[inst.rd as usize] = localDataaUnsigned / localDatabUnsigned;
},
RISCV_OPW_M_REMW => {
machine.int_reg[inst.rd as usize] = localDataa % localDatab;
},
RISCV_OPW_M_REMUW => {
machine.int_reg[inst.rd as usize] = localDataaUnsigned % localDatabUnsigned;
},
_ => {
println!("this instruction ({}) doesn't exists", inst.value);
}
}
} else {
let localDataa = machine.int_reg[inst.rs1 as usize] & 0xffffffff;
let localDatab = machine.int_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[inst.rd as usize] = localDataa + localDatab;
} else { // SUBW
machine.int_reg[inst.rd as usize] = localDataa - localDatab;
}
},
RISCV_OPW_SLLW => {
machine.int_reg[inst.rd as usize] = localDataa << (localDatab & 0x1f);
},
RISCV_OPW_SRW => {
if inst.funct7 == RISCV_OPW_SRW_SRLW {
machine.int_reg[inst.rd as usize] = localDataa >> (localDatab & 0x1f) & machine.shiftmask[32 + localDatab as usize];
} else { // SRAW
machine.int_reg[inst.rd as usize] = localDataa >> (localDatab & 0x1f);
}
},
_ => {
println!("this instruction ({}) doesn't exists", inst.value);
}
}
}
}
_ => { println!("{} opcode non géré", inst.opcode)},
}
}
}
#[cfg(test)]
mod test {
use super::Machine;
}