diff --git a/moo/kernel/test-001.moo b/moo/kernel/test-001.moo
index e0016fa..e854333 100644
--- a/moo/kernel/test-001.moo
+++ b/moo/kernel/test-001.moo
@@ -262,6 +262,27 @@ extend MyObject
 			[ (811306333091350399588761 div: 128) = 6338330727276174996787 ],
 			[ (811306333091350399588761 rem: 128) = 25 ],
 			[ (811306333091350399588761 mod: 128) = 25 ],
+			[ (-811306333091350399588761 div: -16) = 50706645818209399974297 ],
+
+			## 100-104
+			[ (-811306333091350399588761 rem: -16) = -9 ],
+			[ (-811306333091350399588761 mod: -16) = -9 ],
+			[ (-811306333091350399588761 div: -128) = 6338330727276174996787 ],
+			[ (-811306333091350399588761 rem: -128) = -25 ],
+			[ (-811306333091350399588761 mod: -128) = -25 ],
+
+			## 105-109
+			[ (-8113063330913503995887611892379812731289731289312898971231 div: -1024) = 7922913409095218745983995988652160870400128212219627901 ],
+			[ (-8113063330913503995887611892379812731289731289312898971231 rem: -1024) = -607 ],
+			[ (-8113063330913503995887611892379812731289731289312898971231 mod: -1024) = -607 ],
+			[ (-8113063330913503995887611892379812731289731289312898971231 div: -65535) = 123797411015693964994088836383303772507663558240831600 ],
+			[ (-8113063330913503995887611892379812731289731289312898971231 rem: -65535) = -65231 ],
+
+			## 110-114
+			[ (-8113063330913503995887611892379812731289731289312898971231 mod: -65535) = -65231 ],
+			[ (-8113063330913503995887611892379812731289731289312898971231 div: -65536) = 123795522017112792905999937322690013600002003315931685 ],
+			[ (-8113063330913503995887611892379812731289731289312898971231 rem: -65536) = -63071 ],
+			[ (-8113063330913503995887611892379812731289731289312898971231 mod: -65536) = -63071 ],
 
 			## =========================
 			[ 
diff --git a/moo/lib/bigint.c b/moo/lib/bigint.c
index a94e220..6a9040b 100644
--- a/moo/lib/bigint.c
+++ b/moo/lib/bigint.c
@@ -2192,47 +2192,91 @@ moo_oop_t moo_divints (moo_t* moo, moo_oop_t x, moo_oop_t y, int modulo, moo_oop
 					return z;
 
 				default:
-					/* TODO: do division by shifting if both x & y are negative here */
-					if (yv > 0 && IS_POW2(yv) && !MOO_POINTER_IS_NBIGINT(moo, x))
+					/* TODO: do division by shifting if both x & y are in different sign */
+					if (yv < 0)
 					{
-						moo_oow_t nshifts;
-
- 						/* 
-						2**x = v
-						x = log2(v)
-						x is the number of shift to make */
-						nshifts = LOG2_FOR_POW2(yv);
-
-						moo_pushvolat (moo, &x);
-						moo_pushvolat (moo, &y);
-						z = clone_bigint(moo, x, MOO_OBJ_GET_SIZE(x));
-						moo_popvolats (moo, 2);
-						if (!z) return MOO_NULL;
-
-						rshift_unsigned_array (MOO_OBJ_GET_LIWORD_SLOT(z), MOO_OBJ_GET_SIZE(z), nshifts);
-
-						moo_pushvolat (moo, &x);
-						moo_pushvolat (moo, &y);
-						z = normalize_bigint(moo, z);
-						moo_popvolats (moo, 2);
-						if (!z) return MOO_NULL;
-
-						if (rem) 
+						moo_oow_t yv_neg = -yv;
+						if (IS_POW2(yv_neg) && MOO_POINTER_IS_NBIGINT(moo, x))
 						{
+							moo_oow_t nshifts;
+
+							nshifts = LOG2_FOR_POW2(yv_neg);
+
 							moo_pushvolat (moo, &x);
-							moo_pushvolat (moo, &z);
-							r = moo_mulints(moo, y, z);
-							moo_popvolats (moo, 2);
-							if (!r) return MOO_NULL;
-
-							moo_pushvolat (moo, &z);
-							r = moo_subints(moo, x, r);
+							z = clone_bigint_negated(moo, x, MOO_OBJ_GET_SIZE(x));
 							moo_popvolat (moo);
-							if (!r) return MOO_NULL;
+							if (!z) return MOO_NULL;
 
-							*rem = r;
+							rshift_unsigned_array (MOO_OBJ_GET_LIWORD_SLOT(z), MOO_OBJ_GET_SIZE(z), nshifts);
+
+							moo_pushvolat (moo, &x);
+							z = normalize_bigint(moo, z);
+							moo_popvolat (moo);
+							if (!z) return MOO_NULL;
+
+							if (rem) 
+							{
+								moo_pushvolat (moo, &x);
+								moo_pushvolat (moo, &z);
+								r = moo_mulints(moo, MOO_SMOOI_TO_OOP(yv_neg), z);
+								moo_popvolats (moo, 2);
+								if (!r) return MOO_NULL;
+
+								moo_pushvolat (moo, &z);
+								r = moo_addints(moo, x, r);
+								moo_popvolat (moo);
+								if (!r) return MOO_NULL;
+
+								*rem = r;
+							}
+
+							return z;
+						}
+					}
+					else
+					{
+						/* yv > 0 */
+						if (IS_POW2(yv) && MOO_POINTER_IS_PBIGINT(moo, x))
+						{
+							moo_oow_t nshifts;
+
+							/* 
+							2**x = v
+							x = log2(v)
+							x is the number of shift to make */
+							nshifts = LOG2_FOR_POW2(yv);
+
+							/* no pushvolat() on y as y is SMOOI here */
+							moo_pushvolat (moo, &x);
+							z = clone_bigint(moo, x, MOO_OBJ_GET_SIZE(x));
+							moo_popvolat (moo);
+							if (!z) return MOO_NULL;
+
+							rshift_unsigned_array (MOO_OBJ_GET_LIWORD_SLOT(z), MOO_OBJ_GET_SIZE(z), nshifts);
+
+							moo_pushvolat (moo, &x);
+							z = normalize_bigint(moo, z);
+							moo_popvolat (moo);
+							if (!z) return MOO_NULL;
+
+							if (rem) 
+							{
+								moo_pushvolat (moo, &x);
+								moo_pushvolat (moo, &z);
+								r = moo_mulints(moo, y, z);
+								moo_popvolats (moo, 2);
+								if (!r) return MOO_NULL;
+
+								moo_pushvolat (moo, &z);
+								r = moo_subints(moo, x, r);
+								moo_popvolat (moo);
+								if (!r) return MOO_NULL;
+
+								*rem = r;
+							}
+
+							return z;
 						}
-						return z;
 					}
 					break;
 			}