The document discusses ActionScript and the ActionScript Virtual Machine 2 (AVM2). It provides examples of ActionScript bytecode (ABC) and instructions. It compares AVM1 and AVM2, and explains how AVM2 improved performance through just-in-time compilation and garbage collection. Code examples demonstrate how to compile and disassemble ABC files using tools like Flex SDK and Tamarin.

1. 2011/04/23 ActionScript Flash
#1
ActionScriptVM2
mzp /
1

2. mzp /
SE
> ocaml-nagoya
> ProofCafe
> Scala
2

3. )
Rails 3 + HTML5
http://codefirst.github.com/AsakusaSatellite/
3

4. 2/26 Reject
PHP swf !
OCaml swf
Twitter
swf
! !!
4

5. 2/26 Reject
PHP swf !
OCaml swf
Twitter
swf
! !!
4

6. !
ActionScript Flash !!

7. ActionScript

8. ActionScript
!!

9. As1,2 As3
v.s. →
VM → !
> As1,As2 → AVM1 Flash
> As3 → AVM2
AVM2
7

10. AVM2
AVM1
> JIT !
AS3
> E4X
Flash9 AVM2
8

11. HappyABC
Flash9 Scheme( )
As3 →
OCaml
>
>
9

12. HelloWorld

13. Hello, World!
As3
> swf
> swf
trace("hello");
11

14. Flex SDK[1] asc.jar
> hello.abc
> abc = Actionscript Byte Code
$ java -jar asc.jar hello.as
hello.abc, 79 bytes written
[1]http://opensource.adobe.com/wiki/display/flexsdk/Flex+SDK
12

15. Tamarin[2]
Flash Player AVM2
> Adobe Mozilla
> Firefox
$ shell hello.abc
hello
[2]http://www.mozilla.org/projects/tamarin/
13

16. tamarin abcdump[3]
$ shell abcdump.abc -- hello.abc
// magic 2e0010
// Cpool numbers size 3 3 %
// Cpool strings count 5 size 25 31 %
// Cpool namespaces count 3 size 5 6 %
// Cpool nssets count 2 size 4 5 %
( )
[3]http://d.hatena.ne.jp/nitoyon/20090123/abcdump_build
14

17. function script0$init():*
{
// local_count=2 max_scope=1 max_stack=2
code_len=15
0 getlocal0
1 pushscope
2 findpropstrict trace
4 pushstring "hello"
6 callproperty trace (1)
9 coerce_a
10 setlocal1
11 getlocal1
12 returnvalue
13 kill 1
}
15

18. AVM2
push/pop
16

19. )
1+2
> pushbyte 1
pushbyte 2 ( )
add
17

20. )
1+2
> pushbyte 1: 1
pushbyte 1
> pushbyte 2
add
18

21. )
1+2
> pushbyte 1: 1
> pushbyte 2: 2
pushbyte 1
pushbyte 2
> add
19

22. )
1+2
> pushbyte 1: 1
> pushbyte 2: 2
pushbyte 1
pushbyte 2
add
>
20

23. +α
AVM2
2
21

24. ( )
function script0$init():*
{
// local_count=2 max_scope=1 max_stack=2
code_len=15
0 getlocal0
1 pushscope
2 findpropstrict trace
4 pushstring "hello"
6 callproperty trace (1)
9 coerce_a
10 setlocal1
11 getlocal1
12 returnvalue
13 kill 1
}
22

25. this
getlocal0 // 0 push
pushscope //
AVM2
>0 this
>1
this ” ” push
23

26. ) this
this 0 = this
//
addEventListener(MouseEvent.CLICK, function(e){
// this
});
24

27. ( )
function script0$init():*
{
// local_count=2 max_scope=1 max_stack=2
code_len=15
0 getlocal0
1 pushscope
2 findpropstrict trace
4 pushstring "hello"
6 callproperty trace (1)
9 coerce_a
10 setlocal1
11 getlocal1
12 returnvalue
13 kill 1
}
25

28. trace
// trace
findpropstrict trace
// push
pushstring "hello"
// trace
push
callproperty trace (1)
26

29. trace
findpropstrict trace
pushstring “hello”
callproperty trace(1)
27

30. trace
findpropstrict trace
AVM2
> findpropstrict trace
pushstring “hello”
callproperty trace(1)
28

31. trace
findpropstrict trace
AVM2
> findpropstrict trace
pushstring “hello”
callproperty trace(1)
28

32. trace
pushstring
findpropstrict trace
> pushstring “hello”
callproperty trace(1)
29

33. trace
pushstring
findpropstrict trace
> pushstring “hello”
callproperty trace(1)
29

34. trace
callpropery trace
<obj>.trace(“hello”)
findpropstrict trace
pushstring “hello”
> callproperty trace(1)
30

35. trace
callpropery trace
<obj>.trace(“hello”)
findpropstrict trace
pushstring “hello”
> callproperty trace(1)
30

36. ( )
function script0$init():*
{
// local_count=2 max_scope=1 max_stack=2
code_len=15
0 getlocal0
1 pushscope
2 findpropstrict trace
4 pushstring "hello"
6 callproperty trace (1)
9 coerce_a
10 setlocal1
11 getlocal1
12 returnvalue
13 kill 1
}
31

37. return
// *(any)
coerce_a
// 1
setlocal1
// 1 push
getlocal1
//
returnvalue
// 1
kill 1
32

38. ?
//
pop
//
returnvoid
33

40. ABC
s24 : 24 signed int
u8, u16: n unsigned int
u30, u32,s32 : (un)signed int
> 5
> 1
d64 : (double)
swf (u30 )
35

41. getlocal_0 ABC
opcode u8
36

42. function script0$init():*
{
// local_count=2 max_scope=1 max_stack=2
code_len=15
0 getlocal0
1 pushscope
2 findpropstrict trace
4 pushstring "hello"
6 callproperty trace (1)
9 coerce_a
10 setlocal1
11 getlocal1
12 returnvalue
13 kill 1
}
opcode
37

43. kill 1 1
> opcode 0x08
> u30
u30 7 u8
kill 1 => 0x08 0x01
38

44. function script0$init():*
{
// local_count=2 max_scope=1 max_stack=2
code_len=15
0 getlocal0
1 pushscope
2 findpropstrict trace
4 pushstring "hello"
6 callproperty trace (1)
9 coerce_a
10 setlocal1
11 getlocal1
12 returnvalue
13 kill 1
}
kill
39

45. pushstring
> opcode 0x2c
> u30
30 !
>
40

46. (constant pool; cpool)
int 1, 42, ... pushstring “hello”
string “foo”,
“hello”, ...
... ... 0x2c 0x02
41

47. ABC
> int, uint, string, double
> + (public )
=> As ?
> +
>
42

48. function script0$init():*
{
// local_count=2 max_scope=1 max_stack=2
code_len=15
0 getlocal0
1 pushscope
2 findpropstrict trace
4 pushstring "hello"
6 callproperty trace (1)
9 coerce_a
10 setlocal1
11 getlocal1
12 returnvalue
13 kill 1
}
43

49. AS1,2 AS3 VM →AVM2
ABC Tamarin
AVM2
> As3 1 1
> GC
swf
44

50. AVM2 Overview( )
> http://www.adobe.com/content/dam/Adobe/en/devnet/actionscript/articles/
avm2overview.pdf
swfmill(trunk)
> http://swfmill.org
> svn trunk ABC
tamarin
> verbose
45