Flash 错误#1030:堆栈深度不平衡
我遇到了一个奇怪的问题，代码如下：Flash 错误#1030:堆栈深度不平衡,flash,actionscript-3,Flash,Actionscript 3,我遇到了一个奇怪的问题，代码如下： private function initLevel():void { var levelMap:Array = [ [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0], [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0] ]; for (va
private function initLevel():void {
var levelMap:Array =
[
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],
[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
];
for (var y:* in levelMap) {
for (var x:* in levelMap[y]) {
trace(y, x);
trace(levelMap[y, x]);
}
}
}
levelMap[y, x]
var levelMap:Array = [[0, 100],
[20, 21]];
var something:* = levelMap[levelMap[0], 1]; // 100 - The second element of the first array!
trace(something);
something = levelMap[levelMap[0], 'length']; // 2
trace(something);
var a:Object = {num:0, fun:function(num:uint):void{this.num = num;}};
var b:Object = {num:0};
b[a, 'fun'](10);
trace(a.num); //
trace(b.num); // 10
a.fun.call(b, 10);
90:getscopeobject 1
stack: StackTest
locals: StackTest StackTest *
92:getslot 2
stack: Object? (b)
locals: StackTest StackTest *
94:dup
stack: Object? (b) Object? (Copy of b)
locals: StackTest StackTest *
95:setlocal2
stack: Object? (b)
locals: StackTest StackTest Object? (Copy of b)
96:getscopeobject 1
stack: Object? (b) StackTest
locals: StackTest StackTest Object? (Copy of b)
98:getslot 1
stack: Object? (b) Object? (a)
locals: StackTest StackTest Object? (Copy of b)
100:pushstring "fun"
stack: Object? (b) Object? (a) String ("fun")
locals: StackTest StackTest Object? (Copy of b)
102:getproperty {StackTest...Object}::[]
stack: Object? (b) * (a.fun)
locals: StackTest StackTest Object? (Copy of b)
104:getlocal2
stack: Object? (b) * (a.fun) Object? (Copy of b)
locals: StackTest StackTest Object? (Copy of b)
105:pushbyte 10
stack: Object? (b) * (a.fun) Object? (Copy of b) int (10)
locals: StackTest StackTest Object? (Copy of b)
107:call 1 (Call a closure. 1 is the argument count. Stack: function (a.fun), receiver (Copy of b), arg (10). The result (void) is pushed on the stack.)
stack: Object? (b) * (void)
locals: StackTest StackTest Object? (Copy of b)
109:pop
stack: Object? (b)
locals: StackTest StackTest Object? (Copy of b)
110:kill 2
stack: Object? (b)
locals: StackTest StackTest *
b[1, true, a, 'fun'](10);
foo[foo,'length']
foo["length"]
var foo:Array = [];
foo[foo,'push'](1);
trace(foo);
var inner:Array = [10];
var outter:Array = [1,2,inner];
(inner[outter, 'pop']).call(null)[inner,'push'].call(null,20);
trace(inner);
trace(outter);
var inner:Array = [10];
var outter:Array = [1,2,inner];
outter.pop().push(20);
inner[outter, 'pop']
null[outter,'pop']
(void)[outter,'pop']
var arr:Array = [10];
null[arr,'length'];
function private::initLevel():void /* disp_id 0*/
{
// local_count=2 max_scope=1 max_stack=3 code_len=17
0 getlocal0
1 pushscope
2 pushbyte 10
4 newarray [1]
6 coerce Array
8 setlocal1
9 pushnull
10 getlocal1
11 pushstring "length"
13 getproperty null
15 pop
16 returnvoid
}
instr stack_state comments
-------------------------------------------------------------------------------------------
0 this "this" is always passed in local register 0 to instance methods
1 "this" is added to the scope chain and popped
2 10 now, we have 10 on the stack
4 [10] an array is created and initialized taking 1 element from the stack
6 [10] this is sort of like doing [10] as Array
8 the array is assigned to local variable 1
9 null null is pushed. That is the null in this line:
null[arr,'length']
HERE BEGINS THE PROBLEM!
10 null,local1 local 1 is pushed
11 null,local1,"length" the string constant "length" is pushed
13 null,local1["length"] getproperty null is used for dynamic lookup (object["prop"]). Both operands are popped from the stack
15 null in the previous step, the result of local1["lengtht"] was pushed. But we dind't use it, so it's discarded
16 null here the method returns. The stack should be empty, but it's not.
The generated code should have popped the null pushed at #9,
or it shouldn't have pushed it in the first place
VerifyError: Error #1030: Stack depth is unbalanced. 1 != 0.
var dummy:int = 1;
var arr:Array = [10];
if(dummy != 0) {
null[arr,'length'];
}
function private::initLevel():void /* disp_id 0*/
{
// local_count=3 max_scope=1 max_stack=3 code_len=27
0 getlocal0
1 pushscope
2 pushbyte 1
4 setlocal1
5 pushbyte 10
7 newarray [1]
9 coerce Array
11 setlocal2
12 getlocal1
13 pushbyte 0
15 ifeq L1
19 pushnull
20 getlocal2
21 pushstring "length"
23 getproperty null
25 pop
L1:
26 returnvoid
}
instr stack_state comments
-------------------------------------------------------------------------------------------
0 this "this" is always passed in local register 0 to instance methods
1 "this" is added to the scope chain and popped
2 1 now, we have 1 on the stack
4 1 is popped and assigned to the local variable 1 (the dummy var in the code)
5 10 10 is pushed
7 [10] an array is created and initialized taking 1 element from the stack
9 [10] this is sort of like doing [10] as Array
11 the array is assigned to local variable 2 (the arr var in the code)
12 local1 local1 (dummy) is pushed
13 local1,0 0 is pushed
15 this instruction consumes (pops) both local1 and 0 to compare them
If this condition is satisfied, it jumps to the label L1
If it is not, it falls-through to the next instruction
(the same as a case label in a switch statement that does not have a break, in Actionscript code)
19 null null is pushed. That is the null in this line:
null[arr,'length']
Again, HERE BEGINS THE PROBLEM!
20 null,local2 local2 is pushed
21 null,local2,"length" the string constant "length" is pushed
23 null,local2["length"] getproperty null is used for dynamic lookup (object["prop"]). Both operands are popped from the stack
25 null the value returned by local2["length"] is discarded
26 null the method returns, but null is not properly popped from the stack!
`[SWF]
Header:
Version: 10
FileLength: 623
FileLengthCompressed: 454
FrameSize: (180,160)
FrameRate: 8
FrameCount: 10
Tags:
[69:FileAttributes] AS3: true, HasMetadata: false, UseDirectBlit: false, UseGPU: false, UseNetwork: false
[09:SetBackgroundColor] Color: #666666
[86:DefineSceneAndFrameLabelData] Scenes: [0] Frame: 0, Name: Scene 1
[83:DefineShape4] ID: 1, ShapeBounds: (-100,1100,-100,1100), EdgeBounds: (0,1000,0,1000)
FillStyles:
[1] [SWFFillStyle] Type: 0 (solid), Color: FFFF0000
LineStyles:`(and so on)
[SWF]
Version: 10
FileLength: 21
FileLengthCompressed: 21
FrameSize: (14,14)
FrameRate: 50
FrameCount: 1
Tags:
SomeClass.staticMethod[var1,var2]
SomeClass.staticMethod(var1,var2)