NASM怎样定义局部数组？
MASM中可以用local定义局部变量，定义数组也很简单。。例如：
localaa:byte
mov byte ptr aa, 1
NASM中有个%local可以定义，但怎么定义数组，没说明。。有知道的吗？
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4.9.3 %local Directive
The %local directive is used to simplify the use of local temporary stack variables allocated in a stack frame. Automatic local variables in C are an example of this kind of variable. The %local directive is most useful when used with the %stacksize (see section 4.9.2 and is also compatible with the %arg directive (see section 4.9.1). It allows simplified reference to variables on the stack which have been allocated typically by using the ENTER instruction (see section B.4.65 for a description of that instruction). An example of its use is the following:
silly_swap:
%push mycontext ; save the current context
%stacksize small ; tell NASM to use bp
%assign %$localsize 0 ; see text for explanation
%local old_ax:word, old_dx:word
enter %$localsize,0 ; see text for explanation
mov ,ax ; swap ax & bx
mov ,dx ; and swap dx & cx
mov ax,bx
mov dx,cx
mov bx,
mov cx,
leave ; restore old bp
ret ;
%pop ; restore original context
The %$localsize variable is used internally by the %local directive and must be defined within the current context before the %local directive may be used. Failure to do so will result in one expression syntax error for each %local variable declared. It then may be used in the construction of an appropriately sized ENTER instruction as shown in the example.
从这段话里面看不出怎么定义数组？是不是和%$localsize有关？
[ 本帖最后由 gjl606 于 2007-12-5 17:53 编辑 ] 如果是：
enter %$localsize 5 ; 5个变量
那怎么访问呢？
第一个： ？
第二个： ？
。。。。。
例子中是:
mov , ax
那总不能是：
mov ] , ax ; 不对吧 如果不能定义数组的话
那就只能多定义几个变量了。
%local old_ax:word, old_dx:word
但不知这些变量在堆栈中怎么分布的？
| |
| old_ax |
|---------------|
| old_dx |
| |
| |
or
| |
| old_dx |
|---------------|
| old_ax |
| |
| |
[ 本帖最后由 gjl606 于 2007-12-5 18:18 编辑 ] 局部的数组就在栈上分配嘛. 移动esp嘛,足够的空间然后赋址,可以用ebp寻址.
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