1. 13 Sep, 2019 28 commits
    • Jacques-Henri Jourdan's avatar
      Reorder Requires so that we do not depend of Export bugs. · 43a1a90f
      Jacques-Henri Jourdan authored
      The general idea is to first import/export modules which are further
      than the current one, and then import/export modules which are close
      dependencies.
      
      This commit tries to use the same order of imports for every file, and
      describes the convention in ProofGuide.md. There is one exception,
      where we do not follow said convention: in program_logic/weakestpre.v,
      using that order would break printing of texan triples (??).
      43a1a90f
  2. 14 Mar, 2019 28 commits
  3. 05 Mar, 2019 28 commits
  4. 29 Oct, 2018 28 commits
    • Jacques-Henri Jourdan's avatar
      wp_pures. · 2950fca6
      Jacques-Henri Jourdan authored
      2950fca6
    • Jacques-Henri Jourdan's avatar
      A specific constructor for injecting values in expressions · 9646293e
      Jacques-Henri Jourdan authored
      We add a specific constructor to the type of expressions for injecting
      values in expressions.
      
      The advantage are :
      - Values can be assumed to be always closed when performing
        substitutions (even though they could contain free variables, but it
        turns out it does not cause any problem in the proofs in
        practice). This means that we no longer need the `Closed` typeclass
        and everything that comes with it (all the reflection-based machinery
        contained in tactics.v is no longer necessary). I have not measured
        anything, but I guess this would have a significant performance
        impact.
      
      - There is only one constructor for values. As a result, the AsVal and
        IntoVal typeclasses are no longer necessary: an expression which is
        a value will always unify with `Val _`, and therefore lemmas can be
        stated using this constructor.
      
      Of course, this means that there are two ways of writing such a thing
      as "The pair of integers 1 and 2": Either by using the value
      constructor applied to the pair represented as a value, or by using
      the expression pair constructor. So we add reduction rules that
      transform reduced pair, injection and closure expressions into values.
      At first, this seems weird, because of the redundancy. But in fact,
      this has some meaning, since the machine migth actually be doing
      something to e.g., allocate the pair or the closure.
      
      These additional steps of computation show up in the proofs, and some
      additional wp_* tactics need to be called.
      9646293e
  5. 13 Jan, 2018 28 commits
  6. 25 Sep, 2017 28 commits
  7. 05 Jan, 2017 28 commits
  8. 03 Jan, 2017 28 commits
  9. 09 Dec, 2016 28 commits
  10. 08 Dec, 2016 28 commits
  11. 07 Dec, 2016 28 commits
  12. 06 Dec, 2016 28 commits
  13. 22 Nov, 2016 28 commits
  14. 09 Nov, 2016 28 commits
  15. 27 Oct, 2016 28 commits
  16. 05 Aug, 2016 28 commits
    • Robbert Krebbers's avatar
    • Robbert Krebbers's avatar
      Iris 3.0: invariants and weakest preconditions encoded in the logic. · 1f589858
      Robbert Krebbers authored
      This commit features:
      
      - A simpler model. The recursive domain equation no longer involves a triple
        containing invariants, physical state and ghost state, but just ghost state.
        Invariants and physical state are encoded using (higher-order) ghost state.
      
      - (Primitive) view shifts are formalized in the logic and all properties about
        it are proven in the logic instead of the model. Instead, the core logic
        features only a notion of raw view shifts which internalizing performing frame
        preserving updates.
      
      - A better behaved notion of mask changing view shifts. In particular, we no
        longer have side-conditions on transitivity of view shifts, and we have a
        rule for introduction of mask changing view shifts |={E1,E2}=> P with
        E2 ⊆ E1 which allows to postpone performing a view shift.
      
      - The weakest precondition connective is formalized in the logic using Banach's
        fixpoint. All properties about the connective are proven in the logic instead
        of directly in the model.
      
      - Adequacy is proven in the logic and uses a primitive form of adequacy for
        uPred that only involves raw views shifts and laters.
      
      Some remarks:
      
      - I have removed binary view shifts. I did not see a way to describe all rules
        of the new mask changing view shifts using those.
      - There is no longer the need for the notion of "frame shifting assertions" and
        these are thus removed. The rules for Hoare triples are thus also stated in
        terms of primitive view shifts.
      
      TODO:
      
      - Maybe rename primitive view shift into something more sensible
      - Figure out a way to deal with closed proofs (see the commented out stuff in
        tests/heap_lang and tests/barrier_client).
      1f589858
  17. 20 Jul, 2016 28 commits
  18. 19 Jul, 2016 28 commits
    • Robbert Krebbers's avatar
      Implement substitution by reification. · dd543f95
      Robbert Krebbers authored
      We reify to a representation of expressions that includes an explicit
      constructor for closed terms. Substitution can then be implemented as
      the identify, which enables us to perform it using computation.
      dd543f95
  19. 15 Jul, 2016 28 commits
  20. 23 Jun, 2016 28 commits
  21. 19 Apr, 2016 28 commits
  22. 20 Mar, 2016 28 commits
  23. 15 Mar, 2016 28 commits