https://github.com/akkartik/mu/blob/main/318counter.subx
 1 # A rudimentary counter that can be called from anywhere.
 2 
 3 == code
 4 
 5 count-event:
 6     # . prologue
 7     55/push-ebp
 8     89/<- %ebp 4/r32/esp
 9     #
10     ff 0/subop/increment *Foo
11 $count-event:end:
12     # . epilogue
13     89/<- %esp 5/r32/ebp
14     5d/pop-to-ebp
15     c3/return
16 
17 count-of-events:  # -> _/eax: int
18     # . prologue
19     55/push-ebp
20     89/<- %ebp 4/r32/esp
21     #
22     8b/-> *Foo 0/r32/eax
23 $count-of-events:end:
24     # . epilogue
25     89/<- %esp 5/r32/ebp
26     5d/pop-to-ebp
27     c3/return
28 
29 == data
30 Foo:
31   0/imm32