diff --git a/src/execute.c b/src/execute.c
index dc0d4d8..cc5d0ba 100644
--- a/src/execute.c
+++ b/src/execute.c
@@ -169,7 +169,7 @@ static void executeDPImmediate(Machine *state, a64inst_instruction *inst) {
 
                 case(a64inst_MOVK):;
                     dword result = readRegister(state, dest, regType);
-                    result = (result & ~(((1 << DPI_WIDEMOV_SHIFT) - 1) << shiftScalar * DPI_WIDEMOV_SHIFT)) | wideMovImm;
+                    result = (result & ~(((1lu << DPI_WIDEMOV_SHIFT) - 1) << shiftScalar * DPI_WIDEMOV_SHIFT)) | wideMovImm;
                     writeRegister(state, dest, regType, result); 
                     break;