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Add cmp_rm32_r32(0x39) instruction

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tuz358
2018-03-06 11:39:30 +09:00
parent 812a585e9a
commit e38ea011d0
2 changed files with 55 additions and 0 deletions
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1
include/instructions.h
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@@ -42,6 +42,7 @@ public:
void xor_rm32_r32(); // 0x31 void xor_rm32_r32(); // 0x31
void xor_r32_rm32(); // 0x33 void xor_r32_rm32(); // 0x33
void xor_eax_imm32(); // 0x35 void xor_eax_imm32(); // 0x35
void cmp_rm32_r32(); // 0x39
void inc_eax(); // 0x40 void inc_eax(); // 0x40
void inc_ecx(); // 0x41 void inc_ecx(); // 0x41
void inc_edx(); // 0x42 void inc_edx(); // 0x42

54
instructions.cpp
View File

@@ -35,6 +35,7 @@ void Instructions::init_instructions(){
this->instructions[0x31] = &Instructions::xor_rm32_r32; this->instructions[0x31] = &Instructions::xor_rm32_r32;
this->instructions[0x33] = &Instructions::xor_r32_rm32; this->instructions[0x33] = &Instructions::xor_r32_rm32;
this->instructions[0x35] = &Instructions::xor_eax_imm32; this->instructions[0x35] = &Instructions::xor_eax_imm32;
this->instructions[0x39] = &Instructions::cmp_rm32_r32;
this->instructions[0x40] = &Instructions::inc_eax; this->instructions[0x40] = &Instructions::inc_eax;
this->instructions[0x41] = &Instructions::inc_ecx; this->instructions[0x41] = &Instructions::inc_ecx;
this->instructions[0x42] = &Instructions::inc_edx; this->instructions[0x42] = &Instructions::inc_edx;
@@ -640,6 +641,59 @@ void Instructions::xor_eax_imm32(){
this->registers[0] ^= imm32; this->registers[0] ^= imm32;
} }
void Instructions::cmp_rm32_r32(){
//printf("cmp_rm32_r32 called.\n");
uint32_t addr, dst, imm32, result;
uint8_t imm8;
this->modrm = memory.read_uint8(this->eip);
this->calc_modrm();
switch (this->mod) {
case 0:
// cmp [M], R
// addr : M
this->eip++;
addr = this->registers[this->M];
// dst : data of [M]
dst = memory.read_uint32(addr);
result = dst - this->registers[this->R];
set_flag(!result, ZF);
break;
case 1:
// cmp [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);
result = dst - this->registers[this->R];
set_flag(!result, ZF);
break;
case 2:
// cmp [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);
result = dst - this->registers[this->R];
set_flag(!result, ZF);
this->eip += 4;
break;
default:
// case mod == 3
// cmp M, R
this->eip++;
result = this->registers[this->M] - this->registers[this->R];
set_flag(!result, ZF);
break;
}
}
void Instructions::inc_eax(){ void Instructions::inc_eax(){
//printf("inc_eax called.\n"); //printf("inc_eax called.\n");
this->registers[0]++; this->registers[0]++;