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Add opcode_83(0x83) instruction

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tuz358
2018-03-05 11:37:10 +09:00
parent b161f2b85f
commit 5894c46d10
2 changed files with 21 additions and 4 deletions
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3
include/instructions.h
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@@ -29,6 +29,7 @@ public:
void add_rm32_r32(); // 0x01
void xor_rm32_r32(); // 0x31
void dec_ecx(); // 0x49
void opcode_83(); // 0x83
void mov_rm32_r32(); // 0x89
void nop(); // 0x90
void mov_ecx_imm32(); // 0xb9
@@ -37,5 +38,5 @@ public:
void hlt(); // 0xf4
void opcode_ff(); // 0xff
void cmp_rm32_imm8();
void cmp_rm32_imm8(); // called by opcode_83
};

22
instructions.cpp
View File

@@ -23,6 +23,7 @@ void Instructions::init_instructions(){
this->instructions[0x01] = &Instructions::add_rm32_r32;
this->instructions[0x31] = &Instructions::xor_rm32_r32;
this->instructions[0x49] = &Instructions::dec_ecx;
this->instructions[0x83] = &Instructions::opcode_83;
this->instructions[0x89] = &Instructions::mov_rm32_r32;
this->instructions[0x90] = &Instructions::nop;
this->instructions[0xb9] = &Instructions::mov_ecx_imm32;
@@ -153,6 +154,21 @@ void Instructions::dec_ecx(){
this->registers[1]--;
}
void Instructions::opcode_83(){
printf("opcode_83 called.\n");
this->modrm = memory.read_uint8(this->eip);
this->calc_modrm();
switch (this->R) {
case 7:
cmp_rm32_imm8();
break;
default:
break;
}
}
void Instructions::mov_rm32_r32(){
printf("mov_rm32_r32 called.\n");
uint32_t addr, imm32;
@@ -255,14 +271,14 @@ void Instructions::opcode_ff(){
void Instructions::cmp_rm32_imm8(){
printf("cmp_rm32_imm8 called.\n");
this->modrm = memory.read_uint8(this->eip);
this->calc_modrm();
this->eip++;
uint8_t imm8 = memory.read_uint8(this->eip);
printf("imm8: 0x%08x (%d)\n", imm8, imm8);
uint32_t result = this->registers[this->M] - imm8;
set_flag(!result, ZF);
this->eip++;
}
void Instructions::set_flag(int flag, uint32_t flag_type){