Make store-local violations non-trapping. #26
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rmn30
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Looks fine. However I was planning to set up a change log in the ISA doc before merging any ISA changes and ideally would keep the doc in sync with sail with each commit. |
rmn30
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Jan 23, 2024
It's difficult to write defensive code if stores may trap depending on the copied value. Allowing store-local to trap makes it easy to force anything that copies on behalf of a caller able to trap by inserting a local capability into the source that it's copying from. This change is already made in CHERIoT Ibex, the spec is catching up. This also removes the associated exception codes. We may wish to reserve them for a debugging mode for finding places where the tag clearing occurs. Fixes #20.
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It's difficult to write defensive code if stores may trap depending on the copied value. Allowing store-local to trap makes it easy to force anything that copies on behalf of a caller able to trap by inserting a local capability into the source that it's copying from.
This change is already made in CHERIoT Ibex, the spec is catching up.
This also removes the associated exception codes. We may wish to reserve them for a debugging mode for finding places where the tag clearing occurs.
Fixes #20.