Some lemmas that were specific instances of more general lemmas have
been removed from the library. In most cases, broken references could
simply be replaced with the more general fact.
* tcb_context rephrasing to (tcb_context o tcb_arch) and respectively
for set operations
* unfolding of reserved_irq for trivially solving most lemmas
* Changes to the inductive definition of integrity_obj to account for
tcb_arch and tcb_context new location
* Changes to the tcb examples in ExampleSystem to include tcb_arch
* Rephrasing of domain_sep_inv to accommodate the ReservedIRQ case
* Mostly rephrasing of tcb_context to (some form of) (tcb_context o tcb_arch)
* Trivial unfolding of handle_reserved_irq for hoare rules
* Examples in Example_Valid_State.thy were updated
* Nothing remarkable, mostly rephrasing of tcb_context and ReservedIRQ
handling
* Fun fact, some proofs are now shorter
tags: [VER-623][SELFOUR-413]
These changes to the automatons are required by:
SELFOUR-242: invert bitfield scheduler and optimise fast path
Details:
When we enter the kernel, the domain time left (ksDomainTime) is never zero.
If we entered on a timer interrupt, we may decrement it to zero before the
scheduler runs. If we do so, we set the scheduler state to choose_new_thread.
When choosing a new thread, the scheduler switches to a new domain if the
present one is required, and sets the new domain time left from domain_list
(ksDomSchedule).
When entering the kernel on a non-interrupt event, we never touch the domain
time left, which trivially preserves the new constraints.
To prove these, we had to ban a transition from kernel entry to kernel being
preempted when handling an interrupt event in InfoFlow. This is fine, as by
design handling interrupts is not meant to be preempted by interrupts.
To finish the proof of refinement to C, the specification for checkPrio
needed strengthening: the checkPrio spec now takes a machine word
argument. In the spec, priorities are still stored as 8-bit quantities,
however. Once the spec was strenthened, it was possible to remove some
redundant checks and mask operations from the C code.
A thread's maximum controlled priority (MCP) determines the maximum
thread priority or MCP it can assign to another thread (or itself).
* commit 'ecbb860532b4c576fc4726a805802f16bcf5302c': (29 commits)
autocorres-crefine: specialise corres_no_failI for compatibility with Refine
Add license tags for autocorres-crefine files
crefine: refactor AutoCorresTest a bit
autocorres-crefine: remove local debugging imports
Fix InfoFlowC to accommodate corres_underlying changes.
Fix DRefine to accommodate corres_underlying changes.
autocorres-crefine: experiment with manually translating a function (clzl).
autocorres-crefine: experiment with translating bitfield_gen specs.
autocorres-crefine: start a test case for function calls.
autocorres-crefine: update example proofs to work with no_c_termination, which does not require proving termination for the C spec.
autocorres: add user option "no_c_termination" for previous patch.
Making termination proof optional for AutoCorres.
WIP: autocorres: hacky proof of concept for incremental translation.
autocorres: add some missing WordAbstract rules.
autocorres-crefine: fix some comments in work theory.
autocorres-crefine: prove modifies and (simple) terminates specs.
autocorres-crefine: experiment with generating modifies proofs
autocorres-crefine: run autocorres in kernel_all_substitute locale
autocorres-crefine: update another corres_UL that snuck in before rebasing.
autocorres-crefine: working ccorres for handleYield (modulo some white lies).
...
This commit should at least remove merge conflict markers, and the idea
is that at least refine, crefine, drefine, and infoflow (with sorrys)
build. Subsequent commits may be required to fix build issues that I
have not picked up.
Matthew Brecknell
Alejandro Gomez-Londono
Xin,Gao
Miki Tanaka
Joel Beeren
Rafal Kolanski
Thomas Sewell
Matthew Brecknell
Japheth Lim
Gerwin Klein
Daniel Matichuk
Sophie Taylor
Ramana Kumar