656b840e7f
It turns out floating-point operations set different flags than most instructions. We have to branch on them using unsigned jumps. https://stackoverflow.com/questions/7057501/x86-assembler-floating-point-compare/7057771#7057771
408 lines
11 KiB
C++
408 lines
11 KiB
C++
//: jump to 8-bit offset
|
|
|
|
//:: jump
|
|
|
|
:(before "End Initialize Op Names")
|
|
put_new(Name, "eb", "jump disp8 bytes away (jmp)");
|
|
|
|
:(code)
|
|
void test_jump_disp8() {
|
|
run(
|
|
"== code 0x1\n"
|
|
// op ModR/M SIB displacement immediate
|
|
" eb 05 \n" // skip 1 instruction
|
|
" 05 00 00 00 01 \n"
|
|
" 05 00 00 00 02 \n"
|
|
);
|
|
CHECK_TRACE_CONTENTS(
|
|
"run: 0x00000001 opcode: eb\n"
|
|
"run: jump 5\n"
|
|
"run: 0x00000008 opcode: 05\n"
|
|
);
|
|
CHECK_TRACE_DOESNT_CONTAIN("run: 0x00000003 opcode: 05");
|
|
}
|
|
|
|
:(before "End Single-Byte Opcodes")
|
|
case 0xeb: { // jump disp8
|
|
int8_t offset = static_cast<int>(next());
|
|
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
|
|
EIP += offset;
|
|
break;
|
|
}
|
|
|
|
//:: jump if equal/zero
|
|
|
|
:(before "End Initialize Op Names")
|
|
put_new(Name, "74", "jump disp8 bytes away if equal, if ZF is set (jcc/jz/je)");
|
|
|
|
:(code)
|
|
void test_je_disp8_success() {
|
|
ZF = true;
|
|
run(
|
|
"== code 0x1\n"
|
|
// op ModR/M SIB displacement immediate
|
|
" 74 05 \n" // skip 1 instruction
|
|
" 05 00 00 00 01 \n"
|
|
" 05 00 00 00 02 \n"
|
|
);
|
|
CHECK_TRACE_CONTENTS(
|
|
"run: 0x00000001 opcode: 74\n"
|
|
"run: jump 5\n"
|
|
"run: 0x00000008 opcode: 05\n"
|
|
);
|
|
CHECK_TRACE_DOESNT_CONTAIN("run: 0x00000003 opcode: 05");
|
|
}
|
|
|
|
:(before "End Single-Byte Opcodes")
|
|
case 0x74: { // jump disp8 if ZF
|
|
const int8_t offset = static_cast<int>(next());
|
|
if (ZF) {
|
|
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
|
|
EIP += offset;
|
|
}
|
|
break;
|
|
}
|
|
|
|
:(code)
|
|
void test_je_disp8_fail() {
|
|
ZF = false;
|
|
run(
|
|
"== code 0x1\n"
|
|
// op ModR/M SIB displacement immediate
|
|
" 74 05 \n" // skip 1 instruction
|
|
" 05 00 00 00 01 \n"
|
|
" 05 00 00 00 02 \n"
|
|
);
|
|
CHECK_TRACE_CONTENTS(
|
|
"run: 0x00000001 opcode: 74\n"
|
|
"run: 0x00000003 opcode: 05\n"
|
|
"run: 0x00000008 opcode: 05\n"
|
|
);
|
|
CHECK_TRACE_DOESNT_CONTAIN("run: jump 5");
|
|
}
|
|
|
|
//:: jump if not equal/not zero
|
|
|
|
:(before "End Initialize Op Names")
|
|
put_new(Name, "75", "jump disp8 bytes away if not equal, if ZF is not set (jcc/jnz/jne)");
|
|
|
|
:(code)
|
|
void test_jne_disp8_success() {
|
|
ZF = false;
|
|
run(
|
|
"== code 0x1\n"
|
|
// op ModR/M SIB displacement immediate
|
|
" 75 05 \n" // skip 1 instruction
|
|
" 05 00 00 00 01 \n"
|
|
" 05 00 00 00 02 \n"
|
|
);
|
|
CHECK_TRACE_CONTENTS(
|
|
"run: 0x00000001 opcode: 75\n"
|
|
"run: jump 5\n"
|
|
"run: 0x00000008 opcode: 05\n"
|
|
);
|
|
CHECK_TRACE_DOESNT_CONTAIN("run: 0x00000003 opcode: 05");
|
|
}
|
|
|
|
:(before "End Single-Byte Opcodes")
|
|
case 0x75: { // jump disp8 if !ZF
|
|
const int8_t offset = static_cast<int>(next());
|
|
if (!ZF) {
|
|
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
|
|
EIP += offset;
|
|
}
|
|
break;
|
|
}
|
|
|
|
:(code)
|
|
void test_jne_disp8_fail() {
|
|
ZF = true;
|
|
run(
|
|
"== code 0x1\n"
|
|
// op ModR/M SIB displacement immediate
|
|
" 75 05 \n" // skip 1 instruction
|
|
" 05 00 00 00 01 \n"
|
|
" 05 00 00 00 02 \n"
|
|
);
|
|
CHECK_TRACE_CONTENTS(
|
|
"run: 0x00000001 opcode: 75\n"
|
|
"run: 0x00000003 opcode: 05\n"
|
|
"run: 0x00000008 opcode: 05\n"
|
|
);
|
|
CHECK_TRACE_DOESNT_CONTAIN("run: jump 5");
|
|
}
|
|
|
|
//:: jump if greater
|
|
|
|
:(before "End Initialize Op Names")
|
|
put_new(Name, "7f", "jump disp8 bytes away if greater, if ZF is unset and SF == OF (jcc/jg/jnle)");
|
|
put_new(Name, "77", "jump disp8 bytes away if greater (addr, float), if ZF is unset and CF is unset (jcc/ja/jnbe)");
|
|
|
|
:(code)
|
|
void test_jg_disp8_success() {
|
|
ZF = false;
|
|
SF = false;
|
|
OF = false;
|
|
run(
|
|
"== code 0x1\n"
|
|
// op ModR/M SIB displacement immediate
|
|
" 7f 05 \n" // skip 1 instruction
|
|
" 05 00 00 00 01 \n"
|
|
" 05 00 00 00 02 \n"
|
|
);
|
|
CHECK_TRACE_CONTENTS(
|
|
"run: 0x00000001 opcode: 7f\n"
|
|
"run: jump 5\n"
|
|
"run: 0x00000008 opcode: 05\n"
|
|
);
|
|
CHECK_TRACE_DOESNT_CONTAIN("run: 0x00000003 opcode: 05");
|
|
}
|
|
|
|
:(before "End Single-Byte Opcodes")
|
|
case 0x7f: { // jump disp8 if SF == OF and !ZF
|
|
const int8_t offset = static_cast<int>(next());
|
|
if (SF == OF && !ZF) {
|
|
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
|
|
EIP += offset;
|
|
}
|
|
break;
|
|
}
|
|
case 0x77: { // jump disp8 if !CF and !ZF
|
|
const int8_t offset = static_cast<int>(next());
|
|
if (!CF && !ZF) {
|
|
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
|
|
EIP += offset;
|
|
}
|
|
break;
|
|
}
|
|
|
|
:(code)
|
|
void test_jg_disp8_fail() {
|
|
ZF = false;
|
|
SF = true;
|
|
OF = false;
|
|
run(
|
|
"== code 0x1\n"
|
|
// op ModR/M SIB displacement immediate
|
|
" 7f 05 \n" // skip 1 instruction
|
|
" 05 00 00 00 01 \n"
|
|
" 05 00 00 00 02 \n"
|
|
);
|
|
CHECK_TRACE_CONTENTS(
|
|
"run: 0x00000001 opcode: 7f\n"
|
|
"run: 0x00000003 opcode: 05\n"
|
|
"run: 0x00000008 opcode: 05\n"
|
|
);
|
|
CHECK_TRACE_DOESNT_CONTAIN("run: jump 5");
|
|
}
|
|
|
|
//:: jump if greater or equal
|
|
|
|
:(before "End Initialize Op Names")
|
|
put_new(Name, "7d", "jump disp8 bytes away if greater or equal, if SF == OF (jcc/jge/jnl)");
|
|
put_new(Name, "73", "jump disp8 bytes away if greater or equal (addr, float), if CF is unset (jcc/jae/jnb)");
|
|
|
|
:(code)
|
|
void test_jge_disp8_success() {
|
|
SF = false;
|
|
OF = false;
|
|
run(
|
|
"== code 0x1\n"
|
|
// op ModR/M SIB displacement immediate
|
|
" 7d 05 \n" // skip 1 instruction
|
|
" 05 00 00 00 01 \n"
|
|
" 05 00 00 00 02 \n"
|
|
);
|
|
CHECK_TRACE_CONTENTS(
|
|
"run: 0x00000001 opcode: 7d\n"
|
|
"run: jump 5\n"
|
|
"run: 0x00000008 opcode: 05\n"
|
|
);
|
|
CHECK_TRACE_DOESNT_CONTAIN("run: 0x00000003 opcode: 05");
|
|
}
|
|
|
|
:(before "End Single-Byte Opcodes")
|
|
case 0x7d: { // jump disp8 if SF == OF
|
|
const int8_t offset = static_cast<int>(next());
|
|
if (SF == OF) {
|
|
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
|
|
EIP += offset;
|
|
}
|
|
break;
|
|
}
|
|
case 0x73: { // jump disp8 if !CF
|
|
const int8_t offset = static_cast<int>(next());
|
|
if (!CF) {
|
|
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
|
|
EIP += offset;
|
|
}
|
|
break;
|
|
}
|
|
|
|
:(code)
|
|
void test_jge_disp8_fail() {
|
|
SF = true;
|
|
OF = false;
|
|
run(
|
|
"== code 0x1\n"
|
|
// op ModR/M SIB displacement immediate
|
|
" 7d 05 \n" // skip 1 instruction
|
|
" 05 00 00 00 01 \n"
|
|
" 05 00 00 00 02 \n"
|
|
);
|
|
CHECK_TRACE_CONTENTS(
|
|
"run: 0x00000001 opcode: 7d\n"
|
|
"run: 0x00000003 opcode: 05\n"
|
|
"run: 0x00000008 opcode: 05\n"
|
|
);
|
|
CHECK_TRACE_DOESNT_CONTAIN("run: jump 5");
|
|
}
|
|
|
|
//:: jump if lesser
|
|
|
|
:(before "End Initialize Op Names")
|
|
put_new(Name, "7c", "jump disp8 bytes away if lesser, if SF != OF (jcc/jl/jnge)");
|
|
put_new(Name, "72", "jump disp8 bytes away if lesser (addr, float), if CF is set (jcc/jb/jnae)");
|
|
|
|
:(code)
|
|
void test_jl_disp8_success() {
|
|
ZF = false;
|
|
SF = true;
|
|
OF = false;
|
|
run(
|
|
"== code 0x1\n"
|
|
// op ModR/M SIB displacement immediate
|
|
" 7c 05 \n" // skip 1 instruction
|
|
" 05 00 00 00 01 \n"
|
|
" 05 00 00 00 02 \n"
|
|
);
|
|
CHECK_TRACE_CONTENTS(
|
|
"run: 0x00000001 opcode: 7c\n"
|
|
"run: jump 5\n"
|
|
"run: 0x00000008 opcode: 05\n"
|
|
);
|
|
CHECK_TRACE_DOESNT_CONTAIN("run: 0x00000003 opcode: 05");
|
|
}
|
|
|
|
:(before "End Single-Byte Opcodes")
|
|
case 0x7c: { // jump disp8 if SF != OF
|
|
const int8_t offset = static_cast<int>(next());
|
|
if (SF != OF) {
|
|
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
|
|
EIP += offset;
|
|
}
|
|
break;
|
|
}
|
|
case 0x72: { // jump disp8 if CF
|
|
const int8_t offset = static_cast<int>(next());
|
|
if (CF) {
|
|
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
|
|
EIP += offset;
|
|
}
|
|
break;
|
|
}
|
|
|
|
:(code)
|
|
void test_jl_disp8_fail() {
|
|
ZF = false;
|
|
SF = false;
|
|
OF = false;
|
|
run(
|
|
"== code 0x1\n"
|
|
// op ModR/M SIB displacement immediate
|
|
" 7c 05 \n" // skip 1 instruction
|
|
" 05 00 00 00 01 \n"
|
|
" 05 00 00 00 02 \n"
|
|
);
|
|
CHECK_TRACE_CONTENTS(
|
|
"run: 0x00000001 opcode: 7c\n"
|
|
"run: 0x00000003 opcode: 05\n"
|
|
"run: 0x00000008 opcode: 05\n"
|
|
);
|
|
CHECK_TRACE_DOESNT_CONTAIN("run: jump 5");
|
|
}
|
|
|
|
//:: jump if lesser or equal
|
|
|
|
:(before "End Initialize Op Names")
|
|
put_new(Name, "7e", "jump disp8 bytes away if lesser or equal, if ZF is set or SF != OF (jcc/jle/jng)");
|
|
put_new(Name, "76", "jump disp8 bytes away if lesser or equal (addr, float), if ZF is set or CF is set (jcc/jbe/jna)");
|
|
|
|
:(code)
|
|
void test_jle_disp8_equal() {
|
|
ZF = true;
|
|
SF = false;
|
|
OF = false;
|
|
run(
|
|
"== code 0x1\n"
|
|
// op ModR/M SIB displacement immediate
|
|
" 7e 05 \n" // skip 1 instruction
|
|
" 05 00 00 00 01 \n"
|
|
" 05 00 00 00 02 \n"
|
|
);
|
|
CHECK_TRACE_CONTENTS(
|
|
"run: 0x00000001 opcode: 7e\n"
|
|
"run: jump 5\n"
|
|
"run: 0x00000008 opcode: 05\n"
|
|
);
|
|
CHECK_TRACE_DOESNT_CONTAIN("run: 0x00000003 opcode: 05");
|
|
}
|
|
|
|
:(code)
|
|
void test_jle_disp8_lesser() {
|
|
ZF = false;
|
|
SF = true;
|
|
OF = false;
|
|
run(
|
|
"== code 0x1\n"
|
|
// op ModR/M SIB displacement immediate
|
|
" 7e 05 \n" // skip 1 instruction
|
|
" 05 00 00 00 01 \n"
|
|
" 05 00 00 00 02 \n"
|
|
);
|
|
CHECK_TRACE_CONTENTS(
|
|
"run: 0x00000001 opcode: 7e\n"
|
|
"run: jump 5\n"
|
|
"run: 0x00000008 opcode: 05\n"
|
|
);
|
|
CHECK_TRACE_DOESNT_CONTAIN("run: 0x00000003 opcode: 05");
|
|
}
|
|
|
|
:(before "End Single-Byte Opcodes")
|
|
case 0x7e: { // jump disp8 if ZF or SF != OF
|
|
const int8_t offset = static_cast<int>(next());
|
|
if (ZF || SF != OF) {
|
|
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
|
|
EIP += offset;
|
|
}
|
|
break;
|
|
}
|
|
case 0x76: { // jump disp8 if ZF or CF
|
|
const int8_t offset = static_cast<int>(next());
|
|
if (ZF || CF) {
|
|
trace(Callstack_depth+1, "run") << "jump " << NUM(offset) << end();
|
|
EIP += offset;
|
|
}
|
|
break;
|
|
}
|
|
|
|
:(code)
|
|
void test_jle_disp8_greater() {
|
|
ZF = false;
|
|
SF = false;
|
|
OF = false;
|
|
run(
|
|
"== code 0x1\n"
|
|
// op ModR/M SIB displacement immediate
|
|
" 7e 05 \n" // skip 1 instruction
|
|
" 05 00 00 00 01 \n"
|
|
" 05 00 00 00 02 \n"
|
|
);
|
|
CHECK_TRACE_CONTENTS(
|
|
"run: 0x00000001 opcode: 7e\n"
|
|
"run: 0x00000003 opcode: 05\n"
|
|
"run: 0x00000008 opcode: 05\n"
|
|
);
|
|
CHECK_TRACE_DOESNT_CONTAIN("run: jump 5");
|
|
}
|