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Hi,
We use Cortex R5 & R52 in our product in which a special scenario with MPU disabled is needed.
When MPU disabled, there is a concern that speculative access caused by branch prediction is out
of control.
Can we use BPI (branch predictor invalidate) intsruction to avoid unexpected speculative
access?
For unexcpected speculative access, I mean speculative access to memory byond the program
memory layout.
Condsider branch perdiction, my intention is that,
if BPI executed, branch history is cleared, so branch predictor is forced to re-trained.
Thus only branch target which actually reached ever may be speculatively accessed to.