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Add sub_rm32_r32(0x29) instruction

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tuz358
2018-03-06 11:15:04 +09:00
parent 980902ad17
commit 5d317a3ae9
2 changed files with 51 additions and 0 deletions
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1
include/instructions.h
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@@ -36,6 +36,7 @@ public:
void and_rm32_r32(); // 0x21
void and_r32_rm32(); // 0x23
void and_eax_imm32(); // 0x25
void sub_rm32_r32(); // 0x29
void xor_rm32_r32(); // 0x31
void inc_eax(); // 0x40
void inc_ecx(); // 0x41

50
instructions.cpp
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@@ -29,6 +29,7 @@ void Instructions::init_instructions(){
this->instructions[0x21] = &Instructions::and_rm32_r32;
this->instructions[0x23] = &Instructions::and_r32_rm32;
this->instructions[0x25] = &Instructions::and_eax_imm32;
this->instructions[0x29] = &Instructions::sub_rm32_r32;
this->instructions[0x31] = &Instructions::xor_rm32_r32;
this->instructions[0x40] = &Instructions::inc_eax;
this->instructions[0x41] = &Instructions::inc_ecx;
@@ -423,6 +424,55 @@ void Instructions::and_eax_imm32(){
this->registers[0] &= imm32;
}
void Instructions::sub_rm32_r32(){
//printf("sub_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:
// sub [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:
// sub [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:
// sub [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
// sub M, R
this->eip++;
this->registers[this->M] -= this->registers[this->R];
break;
}
}
void Instructions::xor_rm32_r32(){
//printf("xor_rm32_r32 called.\n");
uint32_t addr, dst, imm32;