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Add xor_rm32_r32(0x31) instruction

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tuz358
2018-03-04 22:02:10 +09:00
parent bed4f79532
commit c2b568b443
2 changed files with 55 additions and 3 deletions
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6
include/instructions.h
View File

@@ -3,6 +3,7 @@
#include <stdlib.h> #include <stdlib.h>
#include <string.h> #include <string.h>
#include "memory.h" #include "memory.h"
#include "utils.h"
class Instructions{ class Instructions{
private: private:
@@ -22,6 +23,7 @@ public:
void calc_modrm(); void calc_modrm();
void execute_opcode(uint8_t opcode); void execute_opcode(uint8_t opcode);
void nop(); void xor_rm32_r32(); // 0x31
void hlt(); void nop(); // 0x90
void hlt(); // 0xf4
}; };

52
instructions.cpp
View File

@@ -20,6 +20,7 @@ void Instructions::init(uint32_t eip, uint32_t esp, Memory memory){
void Instructions::init_instructions(){ void Instructions::init_instructions(){
memset(this->instructions, 0, sizeof(this->instructions)); memset(this->instructions, 0, sizeof(this->instructions));
this->instructions[0x31] = &Instructions::xor_rm32_r32;
this->instructions[0x90] = &Instructions::nop; this->instructions[0x90] = &Instructions::nop;
this->instructions[0xf4] = &Instructions::hlt; this->instructions[0xf4] = &Instructions::hlt;
} }
@@ -34,13 +35,62 @@ void Instructions::init_modrm(){
void Instructions::calc_modrm(){ void Instructions::calc_modrm(){
this->mod = (this->modrm & 0xc0) >> 6; this->mod = (this->modrm & 0xc0) >> 6;
this->R = (this->modrm & 0x38) >> 3; this->R = (this->modrm & 0x38) >> 3;
this->M = this->modrm & 0x07; this->M = this->modrm & 0x07;
} }
void Instructions::execute_opcode(uint8_t opcode){ void Instructions::execute_opcode(uint8_t opcode){
(this->*instructions[opcode])(); (this->*instructions[opcode])();
} }
void Instructions::xor_rm32_r32(){
printf("xor_rm32_r32 called.\n");
uint32_t addr, dst, imm32;
uint8_t imm8;
this->modrm = memory.read_uint8(this->eip);
this->calc_modrm();
switch (this->mod) {
case 0:
// xor [M], R
// addr : M
this->eip++;
addr = this->registers[this->M];
// dst : data of [M]
dst = memory.read_uint32(addr);
memory.write_uint32(addr, dst ^ this->registers[this->R]);
break;
case 1:
// xor [M+imm8], R
this->eip++;
imm8 = memory.read_uint8(this->eip);
// addr : M
addr = this->registers[this->M];
// dst : data of [M+imm8]
dst = memory.read_uint32(addr + imm8);
memory.write_uint32(addr + imm8, dst ^ this->registers[this->R]);
break;
case 2:
// xor [M+imm32], R
this->eip++;
imm32 = memory.read_uint32(this->eip);
imm32 = swap_endian32(imm32);
// addr : M
addr = this->registers[this->M];
// dst : data of [M+imm32]
dst = memory.read_uint32(addr + imm32);
memory.write_uint32(addr, dst ^ this->registers[this->R]);
this->eip += 4;
break;
default:
// case mod == 3
// xor M, R
this->eip++;
this->registers[this->M] ^= this->registers[this->R];
break;
}
}
void Instructions::nop(){ void Instructions::nop(){
printf("nop called.\n"); printf("nop called.\n");
} }