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update PSEMU/CPU.cpp
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@Cherrytree56567
Cherrytree56567 committed Oct 4, 2023
1 parent 7fa6948 commit abffb54
Showing 1 changed file with 22 additions and 24 deletions.
46 changes: 22 additions & 24 deletions PSEMU/CPU.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -59,7 +59,7 @@
* /Add break 0b001101
*/


using uint = std::uint32_t;
// First Add rs and rt then store in rd (register)

void CPU::op_add(uint32_t instruction) {
Expand All @@ -84,7 +84,7 @@ void CPU::op_storebyte(uint32_t instruction) {
uint8_t rs = (instruction >> 21) & 0x1F; // Extract bits 25 to 21
uint8_t rt = (instruction >> 16) & 0x1F; // Extract bits 20 to 16
uint16_t imm = instruction & 0xFFFF; // Extract the immediate value
uint16_t imm_s = (unsigned int)(int16_t)imm; // Extract the immediate value
uint16_t imm_s = (uint)(int16_t)imm; // Extract the immediate value

// Store the value in memory
memory[registers.reg[rs] + imm_s] = registers.reg[rt];
Expand All @@ -106,7 +106,7 @@ void CPU::op_addi(uint32_t instruction) {
uint8_t rs = (instruction >> 21) & 0x1F; // Extract bits 25 to 21
uint8_t rt = (instruction >> 16) & 0x1F; // Extract bits 20 to 16
uint16_t imm = instruction & 0xFFFF; // Extract the immediate value
uint16_t imm_s = (unsigned int)(int16_t)imm; // Extract the immediate value
uint16_t imm_s = (uint)(int16_t)imm; // Extract the immediate value

if (rt > 32) {
Logging console;
Expand All @@ -132,7 +132,7 @@ void CPU::op_addiu(uint32_t instruction) {
uint8_t rs = (instruction >> 21) & 0x1F; // Extract bits 25 to 21
uint8_t rt = (instruction >> 16) & 0x1F; // Extract bits 20 to 16
uint16_t imm = instruction & 0xFFFF; // Extract the immediate value
uint16_t imm_s = (unsigned int)(int16_t)imm; // Extract the immediate value
uint16_t imm_s = (uint)(int16_t)imm; // Extract the immediate value

registers.reg[rt] = imm_s + registers.reg[rs];
}
Expand Down Expand Up @@ -179,7 +179,7 @@ void CPU::op_blez(uint32_t instruction) {
uint8_t rs = (instruction >> 21) & 0x1F; // Extract bits 25 to 21
uint8_t rt = (instruction >> 16) & 0x1F; // Extract bits 20 to 16
uint16_t imm = instruction & 0xFFFF; // Extract the immediate value
uint16_t imm_s = (unsigned int)(int16_t)imm; // Extract the immediate value
uint16_t imm_s = (uint)(int16_t)imm; // Extract the immediate value

if ((int)registers.reg[rs] <= 0) {
registers.pc = registers.pc + (imm_s << 2);
Expand All @@ -194,7 +194,7 @@ void CPU::op_bne(uint32_t instruction) {
uint8_t rs = (instruction >> 21) & 0x1F; // Extract bits 25 to 21
uint8_t rt = (instruction >> 16) & 0x1F; // Extract bits 20 to 16
uint16_t imm = instruction & 0xFFFF; // Extract the immediate value
uint16_t imm_s = (unsigned int)(int16_t)imm; // Extract the immediate value
uint16_t imm_s = (uint)(int16_t)imm; // Extract the immediate value

if (registers.reg[rs] != registers.reg[rt]) {
registers.pc = registers.pc + (imm_s << 2);
Expand All @@ -209,7 +209,7 @@ void CPU::op_bgtz(uint32_t instruction) {
uint8_t rs = (instruction >> 21) & 0x1F; // Extract bits 25 to 21
uint8_t rt = (instruction >> 16) & 0x1F; // Extract bits 20 to 16
uint16_t imm = instruction & 0xFFFF; // Extract the immediate value
uint16_t imm_s = (unsigned int)(int16_t)imm; // Extract the immediate value
uint16_t imm_s = (uint)(int16_t)imm; // Extract the immediate value

if ((int)registers.reg[rs] > 0) {
registers.pc = registers.pc + (imm_s << 2);
Expand All @@ -224,19 +224,19 @@ void CPU::op_div(uint32_t instruction) {
uint8_t rd = (instruction >> 11) & 0x1F; // Extract bits 15 to 11

if ((int)rt == 0){
registers.hi = (unsigned int)rs;
registers.hi = (uint)rs;
if ((int)rs >= 0) {
registers.lo = 0xFFFFFFFF;
}
else {
registers.lo = 1;
}
} else if ((unsigned int)rs == 0x80000000 && (int)rt == -1) {
} else if ((uint)rs == 0x80000000 && (int)rt == -1) {
registers.hi = 0;
registers.lo = 0x80000000;
} else {
registers.hi = (unsigned int)((int)rs % (int)rt);
registers.lo = (unsigned int)((int)rs / (int)rt);
registers.hi = (uint)((int)rs % (int)rt);
registers.lo = (uint)((int)rs / (int)rt);
}
}

Expand All @@ -246,24 +246,22 @@ void CPU::op_divu(uint32_t instruction) {
uint8_t rs = (instruction >> 21) & 0x1F; // Extract bits 25 to 21
uint8_t rt = (instruction >> 16) & 0x1F; // Extract bits 20 to 16
uint8_t rd = (instruction >> 11) & 0x1F; // Extract bits 15 to 11

uint n = registers.reg[rs];
uint d = registers.reg[rt];

uint32_t dividend = static_cast<uint32_t>(registers.reg[rs]); // Convert the register value to an unsigned integer
uint32_t divisor = static_cast<uint32_t>(registers.reg[rt]); // Convert the register value to an unsigned integer

if (divisor != 0) {
registers.lo = dividend / divisor; // Store the quotient in LO
registers.hi = dividend % divisor; // Store the remainder in HI
if (d == 0) {
registers.hi = n;
registers.lo = 0xFFFFFFFF;
} else {
registers.hi = n % d;
registers.lo = n / d;
}

std::cout << "DIVU: RS = " << std::to_string(rs) << ", RT = " << std::to_string(rt) << ", RD = " << std::to_string(rd) << std::endl;
}

void CPU::op_j(uint32_t instruction) {
uint32_t target = (instruction & 0x03FFFFFF) << 2; // Extract the target address and shift it left by 2 bits
uint32_t pc_upper = registers.pc & 0xF0000000; // Extract the upper 4 bits of the current PC value
registers.pc = pc_upper | target; // Set the PC to the target address

std::cout << "J: TARGET = " << std::to_string(target) << std::endl;
uint addr = instruction & 0x3FFFFFF;
next_pc = (next_pc & 0xF0000000) | (instr.addr() << 2);
}

void CPU::op_jal(uint32_t instruction) {
Expand Down

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