finish 2_2

src/2_2.asm

@@ -1,3 +1,7 @@
+; Notes ---
+; RCX, RDX, R8, R9 are the registers specified in Windows ABI
+; for use as the first, second, third and fourth argument respectively
+; all of these are volatile
 
     option casemap:none
 
@@ -12,6 +16,7 @@ right_op2   dword       12345678h
 
 
 title_str   byte        "Listing 2-2", 0
+sep_str     byte        "--------------", nl, 0
 
 fmt_str1    byte        "%lx AND %lx = %lx", nl, 0
 fmt_str2    byte        "%lx OR %lx = %lx", nl, 0
@@ -32,11 +37,11 @@ asm_main PROC
     sub     rsp, 56
 
 ; AND operator
-    lea     rcx, fmt_str1       ; load fmt str address 
-    mov     edx, left_op
-    mov     r8d, right_op1
-    mov     r9d, edx
-    and     r9d, r8d
+    lea     rcx, fmt_str1       ; load address for fmt_str1 into the rcx register
+    mov     edx, left_op        ; move the left_op value into the edx register
+    mov     r8d, right_op1      ; move the right_op value into the r8d register
+    mov     r9d, edx            ; move the edx value into the r9d register, this one is a little confusing to me
+    and     r9d, r8d            ; r9d AND r8d, we also have all of our values into the correct register based on the ABI to call printf
     call    printf
 
     lea     rcx, fmt_str1
@@ -46,6 +51,19 @@ asm_main PROC
     and     r9d, edx
     call    printf
 
+    lea     rcx, sep_str
+    call    printf
+
+; OR operator
+    lea     rcx, fmt_str2       ; load address of fmt_str2 in rcx for use in the printf call
+    mov     edx, left_op
+    mov     r8d, right_op1
+    mov     r9d, edx 
+    or      r8d, r9d 
+    call    printf
+
+    add     rsp, 56
+    ret 
 asm_main ENDP
 
     END