1. 05 Jan, 2017 1 commit
  2. 03 Jan, 2017 1 commit
  3. 09 Dec, 2016 3 commits
  4. 08 Dec, 2016 1 commit
  5. 06 Dec, 2016 2 commits
  6. 22 Nov, 2016 1 commit
  7. 17 Nov, 2016 1 commit
  8. 03 Nov, 2016 1 commit
    • Robbert Krebbers's avatar
      Use symbol ∗ for separating conjunction. · cc31476d
      Robbert Krebbers authored
      The old choice for ★ was a arbitrary: the precedence of the ASCII asterisk *
      was fixed at a wrong level in Coq, so we had to pick another symbol. The ★ was
      a random choice from a unicode chart.
      
      The new symbol ∗ (as proposed by David Swasey) corresponds better to
      conventional practise and matches the symbol we use on paper.
      cc31476d
  9. 01 Nov, 2016 4 commits
  10. 27 Oct, 2016 2 commits
  11. 25 Oct, 2016 2 commits
    • Robbert Krebbers's avatar
      Generalize update tactics into iMod and iModIntro for modalities. · fc30ca08
      Robbert Krebbers authored
      There are now two proof mode tactics for dealing with modalities:
      
      - `iModIntro` : introduction of a modality
      - `iMod pm_trm as (x1 ... xn) "ipat"` : eliminate a modality
      
      The behavior of these tactics can be controlled by instances of the `IntroModal`
      and `ElimModal` type class. We have declared instances for later, except 0,
      basic updates and fancy updates. The tactic `iMod` is flexible enough that it
      can also eliminate an updates around a weakest pre, and so forth.
      
      The corresponding introduction patterns of these tactics are `!>` and `>`.
      
      These tactics replace the tactics `iUpdIntro`, `iUpd` and `iTimeless`.
      
      Source of backwards incompatability: the introduction pattern `!>` is used for
      introduction of arbitrary modalities. It used to introduce laters by stripping
      of a later of each hypotheses.
      fc30ca08
    • Robbert Krebbers's avatar
      Rename rvs -> bupd (basic update), pvs -> fupd (fancy update). · 1b85d654
      Robbert Krebbers authored
      And also rename the corresponding proof mode tactics.
      1b85d654
  12. 06 Oct, 2016 1 commit
  13. 05 Oct, 2016 1 commit
  14. 09 Sep, 2016 1 commit
    • Robbert Krebbers's avatar
      Support for specialization of P₁ -★ .. -★ Pₙ -★ Q where Q is persistent. · 090aaea3
      Robbert Krebbers authored
      Before this commit, given "HP" : P and "H" : P -★ Q with Q persistent, one
      could write:
      
        iSpecialize ("H" with "#HP")
      
      to eliminate the wand in "H" while keeping the resource "HP". The lemma:
      
        own_valid : own γ x ⊢ ✓ x
      
      was the prototypical example where this pattern (using the #) was used.
      
      However, the pattern was too limited. For example, given "H" : P₁ -★ P₂ -★ Q",
      one could not write iSpecialize ("H" with "#HP₁") because P₂ -★ Q is not
      persistent, even when Q is.
      
      So, instead, this commit introduces the following tactic:
      
        iSpecialize pm_trm as #
      
      which allows one to eliminate implications and wands while being able to use
      all hypotheses to prove the premises, as well as being able to use all
      hypotheses to prove the resulting goal.
      
      In the case of iDestruct, we now check whether all branches of the introduction
      pattern start with an `#` (moving the hypothesis to the persistent context) or
      `%` (moving the hypothesis to the pure Coq context). If this is the case, we
      allow one to use all hypotheses for proving the premises, as well as for proving
      the resulting goal.
      090aaea3
  15. 06 Sep, 2016 3 commits
  16. 26 Aug, 2016 2 commits
  17. 25 Aug, 2016 1 commit
  18. 22 Aug, 2016 1 commit
    • Robbert Krebbers's avatar
      Generalize equality of heap_lang so it works on any value. · 8111cab0
      Robbert Krebbers authored
      This is more consistent with CAS, which also can be used on any value.
      Note that being able to (atomically) test for equality of any value and
      being able to CAS on any value is not realistic. See the discussion at
      https://gitlab.mpi-sws.org/FP/iris-coq/issues/26, and in particular JH
      Jourdan's observation:
      
        I think indeed for heap_lang this is just too complicated.
      
        Anyway, the role of heap_lang is not to model any actual
        programming language, but rather to show that we can do proofs
        about certain programs. The fact that you can write unrealistic
        programs is not a problem, IMHO. The only thing which is important
        is that the program that we write are realistic (i.e., faithfully
        represents the algorithm we want to p
      
      This commit is based on a commit by Zhen Zhang who generalized equality
      to work on any literal (and not just integers).
      8111cab0
  19. 09 Aug, 2016 2 commits
  20. 08 Aug, 2016 1 commit
  21. 05 Aug, 2016 3 commits
    • Robbert Krebbers's avatar
      Rename the wp_focus tactic into wp_bind. · 149d1ec6
      Robbert Krebbers authored
      This better reflects the name of the bind rule.
      
      I renamed an internal tactic that was previously called wp_bind into
      wp_bind_core.
      149d1ec6
    • 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
  22. 02 Aug, 2016 3 commits