diff --git a/src/arm/Move.go b/src/arm/Move.go
index c687c2a..bda2948 100644
--- a/src/arm/Move.go
+++ b/src/arm/Move.go
@@ -16,11 +16,11 @@ func MoveRegisterRegister(destination cpu.Register, source cpu.Register) uint32
 
 // MoveRegisterNumber moves a number into the given register.
 func MoveRegisterNumber(destination cpu.Register, number int) (uint32, bool) {
-	if number < 0 {
-		return MoveInvertedWideImmediate(destination, ^number, 0), true
-	}
-
 	if sizeof.Signed(number) <= 2 {
+		if number < 0 {
+			return MoveInvertedWideImmediate(destination, ^number, 0), true
+		}
+
 		return MoveZero(destination, 0, uint16(number)), true
 	}
 
diff --git a/src/arm/Move_test.go b/src/arm/Move_test.go
index 6e02a4e..eebdfc7 100644
--- a/src/arm/Move_test.go
+++ b/src/arm/Move_test.go
@@ -30,7 +30,7 @@ func TestMoveRegisterRegister(t *testing.T) {
 func TestMoveRegisterNumber(t *testing.T) {
 	usagePatterns := []struct {
 		Register cpu.Register
-		Number   int
+		Number   uint64
 		Code     uint32
 	}{
 		// MOVZ
@@ -41,9 +41,10 @@ func TestMoveRegisterNumber(t *testing.T) {
 		{arm.X0, 0x1FFFF, 0xB24043E0},
 		{arm.X0, 0x7FFFFFFF, 0xB2407BE0},
 		{arm.X0, 0xFFFFFFFF, 0xB2407FE0},
+		{arm.X0, 0xC3FFFFFFC3FFFFFF, 0xB2026FE0},
 
 		// MOV (inverted wide immediate)
-		{arm.X0, -1, 0x92800000},
+		{arm.X0, 0xFFFFFFFFFFFFFFFF, 0x92800000},
 		{arm.X0, 0x7FFFFFFFFFFFFFFF, 0x92F00000},
 		{arm.X0, 0x2FFFFFFFF, 0x92DFFFA0}, // not encodable in the GNU assembler
 		{arm.X0, 0x2FFFF, 0x92BFFFA0},     // not encodable in the GNU assembler
@@ -55,7 +56,7 @@ func TestMoveRegisterNumber(t *testing.T) {
 
 	for _, pattern := range usagePatterns {
 		t.Logf("mov %s, %d", pattern.Register, pattern.Number)
-		code, encodable := arm.MoveRegisterNumber(pattern.Register, pattern.Number)
+		code, encodable := arm.MoveRegisterNumber(pattern.Register, int(pattern.Number))
 
 		if pattern.Code != 0 {
 			assert.True(t, encodable)