diff --git a/Extra/x86/PROGRAM.ASM b/Extra/x86/PROGRAM.ASM
@@ -75,18 +75,22 @@ test_pair:
; S(a + b) = sums_cache[a + b]
mov si, offset sums_cache
add si, ax
+ add si, ax
+ add si, bx
add si, bx
mov ax, [si]
mov [bp - 6], ax
; S(a) = sums_cache[a]
sub si, bx
+ sub si, bx
mov ax, [si]
mov [bp - 4], ax
; S(b) = sums_cache[b]
mov si, offset sums_cache
add si, bx
+ add si, bx
mov ax, [si]
mov [bp - 2], ax