diff options
Diffstat (limited to 'qtmips_machine/programmemory.cpp')
| -rw-r--r-- | qtmips_machine/programmemory.cpp | 236 |
1 files changed, 0 insertions, 236 deletions
diff --git a/qtmips_machine/programmemory.cpp b/qtmips_machine/programmemory.cpp deleted file mode 100644 index 2f0e19e..0000000 --- a/qtmips_machine/programmemory.cpp +++ /dev/null @@ -1,236 +0,0 @@ -#include "programmemory.h" -#include <sstream> -#include "qtmipsexception.h" -#include "instructions/arithmetic.h" -#include "instructions/loadstore.h" -#include "instructions/nop.h" -#include "instructions/shift.h" -#include <iostream> - -ProgramMemory::ProgramMemory(MemoryAccess *memory) { - this->memory = memory; -} - -void ProgramMemory::load(ProgramLoader *loader) { - // Load program to memory (just dump it byte by byte, decode is done on demand) - for (unsigned i = 0; i < loader->get_nsec(); i++) { - std::uint32_t base_address = loader->get_address(i); - QVector<std::uint8_t> data = loader->get_data(i); - for (auto it = data.begin(); it < data.end(); it++) { - memory->write_byte(base_address + i, *it); - } - } -} - -#define MASKSUB(VAR, LEN, OFFSET) (((VAR) >> (OFFSET)) & ((1 << (LEN)) - 1)) - -Instruction *ProgramMemory::at(std::uint32_t address) { - if (address % 4) - // TODO different exception (unaligned address) - throw std::exception(); - // Read instruction from memory - std::uint32_t dt = this->memory->read_word(address); - - // Decode instruction - if (dt == 0) - return new InstructionNop(); - std::uint8_t opcode = dt >> 26; // upper 6 bits - if (opcode == 0) { // Arithmetic and shift instructions - return this->decode_r(dt); - } else if (opcode == 2 || opcode == 3) { // Jump instructions - return decode_j(dt, opcode); - } else { - return decode_i(dt, opcode); - } -} - -#define I_UNKNOWN(DATA) throw QTMIPS_EXCEPTION(UnsupportedInstruction, "Unknown instruction, can't decode", QString::number(DATA, 16)) -#define I_UNSUPPORTED(INST) throw QTMIPS_EXCEPTION(UnsupportedInstruction, "Decoded unsupported unstruction", #INST) - -Instruction *ProgramMemory::decode_r(std::uint32_t dt) { - std::uint8_t func = MASKSUB(dt, 6, 0); - - std::uint8_t rs, rt, rd, sa; - rs = MASKSUB(dt, 5, 21); - rt = MASKSUB(dt, 5, 16); - rd = MASKSUB(dt, 5, 11); - sa = MASKSUB(dt, 5, 6); - - if (func < 8) { // Shift instructions - bool variable = false; - enum InstructionShiftT t; - switch (func) { - case 0: - t = IST_LL; - break; - case 2: - t = IST_RL; - break; - case 3: - t = IST_RA; - break; - case 4: - t = IST_LL; - variable = true; - break; - case 6: - t = IST_RL; - variable = true; - break; - case 7: - t = IST_RA; - variable = true; - break; - default: - I_UNKNOWN(dt); - } - if (variable) - return new InstructionShiftVariable(t, rs, rt, rd); - else - return new InstructionShift(t, rt, rd, sa); - } else if (func < 10) { // Jump instructions - // TODO - I_UNKNOWN(dt); - } else if (func > 31 && func < 44) { - enum InstructionArithmeticT type; - switch (func) { - case 32: - type = IAT_ADD; - break; - case 33: - type = IAT_ADDU; - break; - case 34: - type = IAT_SUB; - break; - case 35: - type = IAT_SUBU; - break; - case 36: - type = IAT_AND; - break; - case 37: - type = IAT_OR; - break; - case 38: - type = IAT_XOR; - break; - case 39: - type = IAT_NOR; - break; - case 42: - type = IAT_SLT; - break; - case 43: - type = IAT_SLTU; - break; - default: - I_UNKNOWN(dt); - } - return new InstructionArithmetic(type, rs, rd, rt); - } else { // TODO filter rest - I_UNKNOWN(dt); - } -} - -Instruction *ProgramMemory::decode_j(std::uint32_t dt, std::uint8_t opcode) { - std::uint32_t address = MASKSUB(dt, 26, 0); - // TODO - I_UNKNOWN(dt); -} - -Instruction *ProgramMemory::decode_i(std::uint32_t dt, std::uint8_t opcode) { - // InstructionI - std::uint8_t rs, rt; - rs = MASKSUB(dt, 5, 21); - rt = MASKSUB(dt, 5, 16); - std::uint16_t immediate = MASKSUB(dt, 16, 0); - - if (opcode > 7 && opcode < 16) { - enum InstructionArithmeticImmediateT type; - switch (opcode) { - case 8: - type = IAT_ADDI; - break; - case 9: - type = IAT_ADDIU; - break; - case 10: - type = IAT_SLTI; - break; - case 11: - type = IAT_SLTIU; - break; - case 12: - type = IAT_ANDI; - break; - case 13: - type = IAT_ORI; - break; - case 14: - type = IAT_XORI; - break; - case 15: - type = IAT_LUI; - break; - default: - I_UNKNOWN(dt); - } - return new InstructionArithmeticImmediate(type, rs, rt, immediate); - } else if (opcode > 31 && opcode < 47) { - enum InstructionLoadStoreT type; - bool isload = false; - switch (opcode) { - case 32: - type = ILST_B; - isload = true; - break; - case 33: - type = ILST_HW; - isload = true; - break; - case 34: - type = ILST_WL; - isload = true; - break; - case 35: - type = ILST_W; - isload = true; - break; - case 36: - type = ILST_BU; - isload = true; - break; - case 37: - type = ILST_HU; - isload = true; - break; - case 38: - type = ILST_WR; - isload = true; - break; - case 40: - type = ILST_B; - break; - case 41: - type = ILST_HW; - break; - case 42: - type = ILST_WL; - break; - case 43: - type = ILST_W; - break; - case 46: - type = ILST_WR; - break; - default: - I_UNKNOWN(dt); - } - if (isload) - return new InstructionLoad(type, rs, rt, immediate); - else - return new InstructionStore(type, rs, rt, immediate); - } else - I_UNKNOWN(dt); -} |