ios - iOS 上编译成功但执行汇编 MRC 指令失败？

Question

我尝试在 iOS (iPad/iPhone) 代码中检查 ARM 架构 ID，例如

"mrc p15,0,r1,c0,c0,0"

指令通过编译但无法执行，Xcode显示“EXC_BAD_INSTRUCTION”。有什么建议吗？

Answer 1

来自 ARMv7 架构引用手册:

MRC

Move to ARM core register from Coprocessor causes a coprocessor to transfer a value to an ARM core register or to the condition flags. If no coprocessor can execute the instruction, an Undefined Instruction exception is generated.

显然，只是没有从哪里读取值。