diff --git a/src/parser.c b/src/parser.c
index 0f57bb7..037188f 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -16,22 +16,19 @@
 
 //calculate offsets from string
 void calcluateAddressFormat(a64inst_instruction *instr,  char *operandList[]){
-    if(strcmp(operandList[0][strlen(operandList[0])-1], "{") == 0) {
-        //unsigned immediate offset
-        instr->data.processOpData.addressingMode = a64inst_UNSIGNED_OFFSET;
+    
+    if(strcmp(operandList[1][strlen(operandList[1])-1], "!")==0){
+        instr->data.processOpData.addressingMode = a64inst_PRE_INDEXED;
     } else if(strcmp(operandList[0][strlen(operandList[0])-1], "]") == 0) {
         //post-indexed
         instr->data.processOpData.addressingMode = a64inst_POST_INDEXED;
+    } else if( (strcmp(operandList[1][strlen(operandList[1])-1], "x") == 0)
+                || (strcmp(operandList[1][strlen(operandList[1])-1], "w") == 0)){
+                    //register
+                    instr->data.processOpData.addressingMode = a64inst_REGISTER_OFFSET;
     } else {
-        //check second operand to distinguish between pre-indexed and register
-        if(strcmp(operandList[1][0], "#")==0){
-            //pre-indexed
-            instr->data.processOpData.addressingMode = a64inst_PRE_INDEXED;
-        } else {
-            //register
-            instr->data.processOpData.addressingMode = a64inst_REGISTER_OFFSET;
-        }
-    }
+        instr->data.processOpData.addressingMode = a64inst_UNSIGNED_OFFSET;
+    } 
 }
 
 void generateLoadStoreOperands(a64inst_instruction *instr, char *opcode, char *operandList[]){