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//: jump to 8-bit offset
//:: jump
:(before "End Initialize Op Names")
put_new(Name, "eb", "jump disp8 bytes away (jmp)");
:(scenario jump_rel8)
== 0x1
# op ModR/M SIB displacement immediate
eb 05 # skip 1 instruction
05 00 00 00 01
05 00 00 00 02
+run: inst: 0x00000001
+run: jump 5
+run: inst: 0x00000008
-run: inst: 0x00000003
:(before "End Single-Byte Opcodes")
case 0xeb: { // jump rel8
int8_t offset = static_cast<int>(next());
trace(90, "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)");
:(scenario je_rel8_success)
% ZF = true;
== 0x1
# op ModR/M SIB displacement immediate
74 05 # skip 1 instruction
05 00 00 00 01
05 00 00 00 02
+run: inst: 0x00000001
+run: jump 5
+run: inst: 0x00000008
-run: inst: 0x00000003
:(before "End Single-Byte Opcodes")
case 0x74: { // jump rel8 if ZF
const int8_t offset = static_cast<int>(next());
if (ZF) {
trace(90, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}
:(scenario je_rel8_fail)
% ZF = false;
== 0x1
# op ModR/M SIB displacement immediate
74 05 # skip 1 instruction
05 00 00 00 01
05 00 00 00 02
+run: inst: 0x00000001
+run: inst: 0x00000003
+run: inst: 0x00000008
-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)");
:(scenario jne_rel8_success)
% ZF = false;
== 0x1
# op ModR/M SIB displacement immediate
75 05 # skip 1 instruction
05 00 00 00 01
05 00 00 00 02
+run: inst: 0x00000001
+run: jump 5
+run: inst: 0x00000008
-run: inst: 0x00000003
:(before "End Single-Byte Opcodes")
case 0x75: { // jump rel8 unless ZF
const int8_t offset = static_cast<int>(next());
if (!ZF) {
trace(90, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}
:(scenario jne_rel8_fail)
% ZF = true;
== 0x1
# op ModR/M SIB displacement immediate
75 05 # skip 1 instruction
05 00 00 00 01
05 00 00 00 02
+run: inst: 0x00000001
+run: inst: 0x00000003
+run: inst: 0x00000008
-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)");
:(scenario jg_rel8_success)
% ZF = false;
% SF = false;
% OF = false;
== 0x1
# op ModR/M SIB displacement immediate
7f 05 # skip 1 instruction
05 00 00 00 01
05 00 00 00 02
+run: inst: 0x00000001
+run: jump 5
+run: inst: 0x00000008
-run: inst: 0x00000003
:(before "End Single-Byte Opcodes")
case 0x7f: { // jump rel8 if !SF and !ZF
const int8_t offset = static_cast<int>(next());
if (!ZF && SF == OF) {
trace(90, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}
:(scenario jg_rel8_fail)
% ZF = false;
% SF = true;
% OF = false;
== 0x1
# op ModR/M SIB displacement immediate
7f 05 # skip 1 instruction
05 00 00 00 01
05 00 00 00 02
+run: inst: 0x00000001
+run: inst: 0x00000003
+run: inst: 0x00000008
-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)");
:(scenario jge_rel8_success)
% SF = false;
% OF = false;
== 0x1
# op ModR/M SIB displacement immediate
7d 05 # skip 1 instruction
05 00 00 00 01
05 00 00 00 02
+run: inst: 0x00000001
+run: jump 5
+run: inst: 0x00000008
-run: inst: 0x00000003
:(before "End Single-Byte Opcodes")
case 0x7d: { // jump rel8 if !SF
const int8_t offset = static_cast<int>(next());
if (SF == OF) {
trace(90, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}
:(scenario jge_rel8_fail)
% SF = true;
% OF = false;
== 0x1
# op ModR/M SIB displacement immediate
7d 05 # skip 1 instruction
05 00 00 00 01
05 00 00 00 02
+run: inst: 0x00000001
+run: inst: 0x00000003
+run: inst: 0x00000008
-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)");
:(scenario jl_rel8_success)
% ZF = false;
% SF = true;
% OF = false;
== 0x1
# op ModR/M SIB displacement immediate
7c 05 # skip 1 instruction
05 00 00 00 01
05 00 00 00 02
+run: inst: 0x00000001
+run: jump 5
+run: inst: 0x00000008
-run: inst: 0x00000003
:(before "End Single-Byte Opcodes")
case 0x7c: { // jump rel8 if SF and !ZF
const int8_t offset = static_cast<int>(next());
if (SF != OF) {
trace(90, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}
:(scenario jl_rel8_fail)
% ZF = false;
% SF = false;
% OF = false;
== 0x1
# op ModR/M SIB displacement immediate
7c 05 # skip 1 instruction
05 00 00 00 01
05 00 00 00 02
+run: inst: 0x00000001
+run: inst: 0x00000003
+run: inst: 0x00000008
-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)");
:(scenario jle_rel8_equal)
% ZF = true;
% SF = false;
% OF = false;
== 0x1
# op ModR/M SIB displacement immediate
7e 05 # skip 1 instruction
05 00 00 00 01
05 00 00 00 02
+run: inst: 0x00000001
+run: jump 5
+run: inst: 0x00000008
-run: inst: 0x00000003
:(scenario jle_rel8_lesser)
% ZF = false;
% SF = true;
% OF = false;
== 0x1
# op ModR/M SIB displacement immediate
7e 05 # skip 1 instruction
05 00 00 00 01
05 00 00 00 02
+run: inst: 0x00000001
+run: jump 5
+run: inst: 0x00000008
-run: inst: 0x00000003
:(before "End Single-Byte Opcodes")
case 0x7e: { // jump rel8 if SF or ZF
const int8_t offset = static_cast<int>(next());
if (ZF || SF != OF) {
trace(90, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}
:(scenario jle_rel8_greater)
% ZF = false;
% SF = false;
% OF = false;
== 0x1
# op ModR/M SIB displacement immediate
7e 05 # skip 1 instruction
05 00 00 00 01
05 00 00 00 02
+run: inst: 0x00000001
+run: inst: 0x00000003
+run: inst: 0x00000008
-run: jump 5
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