diff --git a/asm/creole.py b/asm/creole.py
index 1d98051..4cb4b8c 100644
--- a/asm/creole.py
+++ b/asm/creole.py
@@ -92,9 +92,14 @@ class Instruction(Enum):
 	MUL = 4, ArgType.REG, ArgType.VAL, ArgType.VAL
 	DIV = 5, ArgType.REG, ArgType.VAL, ArgType.VAL
 	SDIV = 6, ArgType.REG, ArgType.VAL, ArgType.VAL
-	JL = 7, ArgType.LAB, ArgType.VAL, ArgType.VAL
+	SYS = 7, ArgType.VAL
 	CLB = 8, ArgType.LAB
-	SYS = 9, ArgType.VAL
+	JL = 9, ArgType.LAB, ArgType.VAL, ArgType.VAL
+	JLE = 10, ArgType.LAB, ArgType.VAL, ArgType.VAL
+	JG = 11, ArgType.LAB, ArgType.VAL, ArgType.VAL
+	JGE = 12, ArgType.LAB, ArgType.VAL, ArgType.VAL
+	JE = 13, ArgType.LAB, ArgType.VAL, ArgType.VAL
+	JNE = 13, ArgType.LAB, ArgType.VAL, ArgType.VAL
 
 	def __init__(self, opcode, *args):
 		if opcode > 0x7F or opcode < 0:
@@ -214,6 +219,10 @@ class Program:
 		args_w_type = ins.typecheck(line[1:])
 		self.asm_push_line(ins.opcode, args_w_type)
 
+	def parse_lines(self, lines):
+		for l in lines:
+			self.parse_asm_line(l)
+
 	def __call__(self):
 		b = bytes()
 		for line in self.asm:
diff --git a/asm/ffi.py b/asm/ffi.py
index 4c1ca15..ba327bf 100644
--- a/asm/ffi.py
+++ b/asm/ffi.py
@@ -120,13 +120,15 @@ class Environment:
 
 	def syscall(self, sc):
 		raise InvalidSyscallError(sc)
-	def __call__(self):
+	def __call__(self, debug=False):
 		sc = c_size_t()
 		ret = RunRet.CONTINUE
 		while not ret.is_halt():
 			ret = RunRet(dll.creole_step(byref(self.cenv), byref(sc)))
 			if ret == RunRet.SYSCALL:
 				self.syscall(sc)
+			if debug:
+				print(self.cenv.reg[0])
 		return ret
 
 class CParseLineException(Exception):
diff --git a/asm/test.py b/asm/test.py
index 4b6471c..00e9e5e 100644
--- a/asm/test.py
+++ b/asm/test.py
@@ -309,6 +309,22 @@ class DivTest(unittest.TestCase):
 		self.assertEqual(cm.exception.i, 2)
 		self.assertEqual(cm.exception.opcode, 5)
 
+class LabelTest(unittest.TestCase):
+	def test_simple_loop(self):
+		p = Program()
+		p.parse_lines([
+			"add r0 10 0",
+			"add r1 20 0",
+			"CLB l0",
+			"add r0 r0 -1",
+			"add r1 r1 1",
+			"jg l0 r0 0"
+		])
+		ex = ffi.Environment(p())
+		self.assertEqual(ex(), ffi.RunRet.STOP)
+		self.assertEqual(ex.getreg(0), 0)
+		self.assertEqual(ex.getreg(1), 30)
+
 class ProgramTest(unittest.TestCase):
 	def test_exec_simple_reg(self):
 		p = Program()
diff --git a/creole.c b/creole.c
index 135576f..6a1daa8 100644
--- a/creole.c
+++ b/creole.c
@@ -36,9 +36,14 @@ static const struct {
 	defop(MUL, 3, TYPE_REG, TYPE_VAL, TYPE_VAL),
 	defop(DIV, 3, TYPE_REG, TYPE_VAL, TYPE_VAL),
 	defop(SDIV, 3, TYPE_REG, TYPE_VAL, TYPE_VAL),
-	defop(JL, 3, TYPE_LAB, TYPE_VAL, TYPE_VAL),
+	defop(SYS, 1, TYPE_VAL, TYPE_NONE, TYPE_NONE),
 	defop(CLB, 1, TYPE_LAB, TYPE_NONE, TYPE_NONE),
-	defop(SYS, 1, TYPE_VAL, TYPE_NONE, TYPE_NONE)
+	defop(JL, 3, TYPE_LAB, TYPE_VAL, TYPE_VAL),
+	defop(JLE, 3, TYPE_LAB, TYPE_VAL, TYPE_VAL),
+	defop(JG, 3, TYPE_LAB, TYPE_VAL, TYPE_VAL),
+	defop(JGE, 3, TYPE_LAB, TYPE_VAL, TYPE_VAL),
+	defop(JE, 3, TYPE_LAB, TYPE_VAL, TYPE_VAL),
+	defop(JNE, 3, TYPE_LAB, TYPE_VAL, TYPE_VAL)
 };
 
 /*************************************************************************
@@ -518,6 +523,7 @@ enum creole_run_ret creole_step(struct creole_env *env, creole_word *sc)
 	struct creole_ins *ins = env->prg + env->prgptr;
 	creole_word a1, a2;
 	int rcode = CREOLE_STEP_CONTINUE;
+	int increase_pointer = 1;
 
 	if (env->prgptr == env->prgend)
 		return CREOLE_STEP_STOP;
@@ -556,22 +562,70 @@ enum creole_run_ret creole_step(struct creole_env *env, creole_word *sc)
 		check(creole_reg_write(env, ins->w[0],
 		      (creole_signed)a1 / (creole_signed)a2));
 		break;
+	case CREOLE_SYS:
+		check(read_val(env, ins, 0, sc));
+		rcode = CREOLE_STEP_SYSCALL;
+		break;
 	case CREOLE_JL:
 		check(read_val(env, ins, 1, &a1));
 		check(read_val(env, ins, 2, &a2));
 		check(check_label(env, ins->w[0]));
-		if (a1 < a2)
+		if (a1 < a2) {
 			env->prgptr = env->lab[ins->w[0]];
+			increase_pointer = 0;
+		}
 		break;
-	case CREOLE_SYS:
-		check(read_val(env, ins, 0, sc));
-		rcode = CREOLE_STEP_SYSCALL;
+	case CREOLE_JLE:
+		check(read_val(env, ins, 1, &a1));
+		check(read_val(env, ins, 2, &a2));
+		check(check_label(env, ins->w[0]));
+		if (a1 <= a2) {
+			env->prgptr = env->lab[ins->w[0]];
+			increase_pointer = 0;
+		}
+		break;
+	case CREOLE_JG:
+		check(read_val(env, ins, 1, &a1));
+		check(read_val(env, ins, 2, &a2));
+		check(check_label(env, ins->w[0]));
+		if (a1 > a2) {
+			env->prgptr = env->lab[ins->w[0]];
+			increase_pointer = 0;
+		}
+		break;
+	case CREOLE_JGE:
+		check(read_val(env, ins, 1, &a1));
+		check(read_val(env, ins, 2, &a2));
+		check(check_label(env, ins->w[0]));
+		if (a1 >= a2) {
+			env->prgptr = env->lab[ins->w[0]];
+			increase_pointer = 0;
+		}
+		break;
+	case CREOLE_JE:
+		check(read_val(env, ins, 1, &a1));
+		check(read_val(env, ins, 2, &a2));
+		check(check_label(env, ins->w[0]));
+		if (a1 == a2) {
+			env->prgptr = env->lab[ins->w[0]];
+			increase_pointer = 0;
+		}
+		break;
+	case CREOLE_JNE:
+		check(read_val(env, ins, 1, &a1));
+		check(read_val(env, ins, 2, &a2));
+		check(check_label(env, ins->w[0]));
+		if (a1 != a2) {
+			env->prgptr = env->lab[ins->w[0]];
+			increase_pointer = 0;
+		}
 		break;
 	default:
 		rcode = CREOLE_STEP_UNKNOWN_OPCODE;
 	}
 
-	env->prgptr++;
+	if (increase_pointer)
+		env->prgptr++;
 	return rcode;
 }
 
diff --git a/creole.h b/creole.h
index 452bc91..f5b118f 100644
--- a/creole.h
+++ b/creole.h
@@ -24,9 +24,14 @@ enum creole_opcode {
 	CREOLE_MUL = 4,
 	CREOLE_DIV = 5,
 	CREOLE_SDIV = 6,
-	CREOLE_JL = 7,
+	CREOLE_SYS = 7,
 	CREOLE_CLB = 8,
-	CREOLE_SYS = 9,
+	CREOLE_JL = 9,
+	CREOLE_JLE = 10,
+	CREOLE_JG = 11,
+	CREOLE_JGE = 12,
+	CREOLE_JE = 13,
+	CREOLE_JNE = 14,
 	CREOLE_OPCODE_LEN
 };