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Trace decompressor: Are barrier instructions and synchronization primitives really waypoints?

Dear all,

System: Altera Cyclone V with ARM Cortex-A9 dual-core MPU. CoreSight PFT 1.0

I am currently developing a trace decompressor. I wrote a function that parses the program image in order to get the waypoint information of each instruction.

This article on waypoints tells me to treat barrier instructions like direct branches:

http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ihi0035b/BCGJHDID.html

if i do that, my decoded stream is out of sync at the next i-sync packet. If i treat barrier instructions like non-waypoint-instructions, my decoded stream remains in sync.

The same is true for synchronization primitives.

I am wondering whats going on here, because the arm documentation usually is very reliable and these would be quite big mistakes, so what am i missing here? Can i really regard my decoded stream as valid only because my decompressor calculated the same address as the i-sync packet tells me?

Thank you!

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