| 摘要 |
A data processing apparatus comprises a processing element having associated memory and one or more registers, the processing element being configured to perform processing activities in two or more security modes 200/300 so as to inhibit a processing activity performed in one of the security modes from accessing at least some information associated with a processing activity performed in another of the security modes. In response to a function call causing a branch 220 from a processing activity in a first security mode to a processing activity in a second security mode, the contents of the registers are stored/pushed to stack 232 in the memory storage and when a branch returns 330 to the first security mode, the register contents are retrieved/popped from stack 232. The trace apparatus is configured to generate items of trace data indicative of processing activities and data relating to the retrieval of the register contents from the memory storage. |
