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014jump_relative.cc
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014jump_relative.cc
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//: jump to 8-bit offset
//:: jump
:(scenario jump_rel8)
# op ModRM 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(2, "run") << "jump " << NUM(offset) << end();
EIP += offset;
break;
}
//:: jump if equal/zero
:(scenario je_rel8_success)
% ZF = true;
# op ModRM 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
int8_t offset = static_cast<int>(next());
if (ZF) {
trace(2, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}
:(scenario je_rel8_fail)
% ZF = false;
# op ModRM 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
:(scenario jne_rel8_success)
% ZF = false;
# op ModRM 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
int8_t offset = static_cast<int>(next());
if (!ZF) {
trace(2, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}
:(scenario jne_rel8_fail)
% ZF = true;
# op ModRM 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
:(scenario jg_rel8_success)
% ZF = false;
% SF = false;
% OF = false;
# op ModRM 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
int8_t offset = static_cast<int>(next());
if (!ZF && SF == OF) {
trace(2, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}
:(scenario jg_rel8_fail)
% ZF = false;
% SF = true;
% OF = false;
# op ModRM 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
:(scenario jge_rel8_success)
% SF = false;
% OF = false;
# op ModRM 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
int8_t offset = static_cast<int>(next());
if (SF == OF) {
trace(2, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}
:(scenario jge_rel8_fail)
% SF = true;
% OF = false;
# op ModRM 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
:(scenario jl_rel8_success)
% ZF = false;
% SF = true;
% OF = false;
# op ModRM 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
int8_t offset = static_cast<int>(next());
if (SF != OF) {
trace(2, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}
:(scenario jl_rel8_fail)
% ZF = false;
% SF = false;
% OF = false;
# op ModRM 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
:(scenario jle_rel8_equal)
% ZF = true;
% SF = false;
% OF = false;
# op ModRM 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;
# op ModRM 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
int8_t offset = static_cast<int>(next());
if (ZF || SF != OF) {
trace(2, "run") << "jump " << NUM(offset) << end();
EIP += offset;
}
break;
}
:(scenario jle_rel8_greater)
% ZF = false;
% SF = false;
% OF = false;
# op ModRM 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