diff --git a/src/cpu.rs b/src/cpu.rs
index fda80df..96287d9 100644
--- a/src/cpu.rs
+++ b/src/cpu.rs
@@ -401,8 +401,8 @@ impl I8080 {
                         self.update_arith_flags(ac, self.carry, res);
                         self.regs[src] = res;
                     }
-                    Opcode::Inx(dst) => self.set_pair(dst, self.get_pair(dst) + 1),
-                    Opcode::Dcx(dst) => self.set_pair(dst, self.get_pair(dst) + 2),
+                    Opcode::Inx(dst) => self.set_pair(dst, self.get_pair(dst).wrapping_add(1)),
+                    Opcode::Dcx(dst) => self.set_pair(dst, self.get_pair(dst).wrapping_sub(1)),
                     Opcode::Dad(src) => {
                         let a = u32::from(self.get_pair(RegisterPair::HL));
                         let b = u32::from(self.get_pair(src));