diff --git a/src/execute.c b/src/execute.c
index 7ad18da..1f37999 100644
--- a/src/execute.c
+++ b/src/execute.c
@@ -134,8 +134,8 @@ static void executeDPImmediate(Machine *state, a64inst_instruction *inst) {
                     writeRegister(state, dest, regType, result);
                     
                     updateCondNZ(state, result, regType);
-                    state->conditionCodes.Overflow = srcVal < result;
-                    state->conditionCodes.Carry = state->conditionCodes.Overflow;
+                    state->conditionCodes.Overflow = getMSB(srcVal, regType) != getMSB(arithmImm, regType) && getMSB(arithmImm, regType) == getMSB(result, regType);
+                    state->conditionCodes.Carry = srcVal >= arithmImm;
                     break;
                 
                 case(a64inst_SUB):
@@ -262,7 +262,7 @@ static void executeDPRegister(Machine *state, a64inst_instruction *inst) {
                             writeRegister(state, dest, regType, result);
                             
                             updateCondNZ(state, result, regType);
-                            state->conditionCodes.Overflow = getMSB(src1Val, regType) != getMSB(src2Val, regType) && getMSB(src1Val, regType) != getMSB(result, regType);
+                            state->conditionCodes.Overflow = getMSB(src1Val, regType) != getMSB(src2Val, regType) && getMSB(src2Val, regType) == getMSB(result, regType);
                             state->conditionCodes.Carry = src1Val >= src2Val;
                             break;