SAM4S Target Trace Divergence

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SAM4S Target Trace Divergence #456

Closed alex-dewar closed 1 year ago

alex-dewar commented 1 year ago

The SAM4S seems to sometimes generate traces that look very different for a small portion of the AES algorithm. It's unclear if this is caused by the data that's being processed or some other reason. This doesn't seem to happen with the STM32F3 target with Husky.

alex-dewar commented 1 year ago

Was caused by loop optimizations in the SAM4S. Disabling this fixes the issue. Will close when a fix is pushed

alex-dewar commented 1 year ago

Fixed by 8b46fbd69867c1885066e4176e24f13ee6698db0

colinoflynn commented 1 year ago

Nice catch! Had seen that for a while and never investigated, interesting there is still some flash/cache stuff hidden away a bit. For reference for anyone else, this is the SAM4S feature: