问一下看过ads文档的

wsm

由于要了解一下堆占溢出的检验 看了一下ads的文档
发现它里面对r12有这样的定意:
Register r12 is the intra-call scratch register, ip. It is used in this role in procedure linkage veneers, for example interworking veneers. Between procedure calls you can use it for any purpose. A called routine does not need to restore r12 before returning.
什么意思？不懂
以前看到的文档里都是把r12说明成一个通用寄存器的

Dragonfly

ads? what u mean?   , i do not know.

arm development suite?

wsm

yes

Dragonfly

i have a trial version but never use it.  

register4skyeye

这里的intra-call和interworking都是指ARM/Thumb的交互调用，而interworking veneers则是连接器自动添加的一段用于状态切换的连接程序。
假设有如下调用：
void func1(void)
{
      func2();
}
这里func1是ARM状态，func2是Thumb状态，则在指定编译器命令行选项-acps /interwork时，连接器会自动生成一小段代码veneers来切换状态。