1. 14 Feb, 2016 1 commit
  2. 13 Feb, 2016 2 commits
  3. 11 Feb, 2016 1 commit
  4. 16 Jan, 2016 1 commit
  5. 14 Jan, 2016 1 commit
  6. 12 Jan, 2016 1 commit
  7. 21 Dec, 2015 1 commit
  8. 15 Dec, 2015 2 commits
  9. 18 Nov, 2015 1 commit
  10. 16 Nov, 2015 1 commit
  11. 11 Nov, 2015 1 commit
  12. 03 Feb, 2017 1 commit
  13. 01 Feb, 2017 1 commit
  14. 04 Jun, 2015 1 commit
  15. 22 Apr, 2015 1 commit
  16. 25 Feb, 2015 1 commit
  17. 08 Feb, 2015 2 commits
    • Robbert Krebbers's avatar
      Update copyright headers. · 5a73c4ed
      Robbert Krebbers authored
      5a73c4ed
    • Robbert Krebbers's avatar
      Support function pointers and use a state monad in the frontend. · b2109c25
      Robbert Krebbers authored
      Important changes in the core semantics:
      * Types extended with function types. Since function types are a special kind
        of pointer types, types now have an additional mutual part called "ptr_type".
      * Pointers extended with function pointers. Theses are just names that refer
        to an actual function in the function environment.
      * Typing environments extended to assign argument and return types to function
        names. Before we used a separate environment for these, but since the
        argument and return types are already needed to type function pointers, this
        environment would appear in pretty much every typing judgment.
      
      As a side-effect, the frontend has been rewritten entirely. The important
      changes are:
      
      * Type checking of expressions is more involved: there is a special kind of
        expression type corresponding to a function designator.
      * To handle things like block scoped extern function, more state-fullness was
        needed. To prepare for future extensions, the entire frontend now uses a
        state monad.
      b2109c25
  18. 25 Jan, 2015 1 commit
  19. 15 Nov, 2014 1 commit
    • Robbert Krebbers's avatar
      More accurate formalization of integer ranks. · da7a14bb
      Robbert Krebbers authored
      Integers with the same size, are no longer supposed to have the same rank. As a
      result, the C integer types (char, short, int, long, long long) are different
      (and thus cannot alias) even if they have the same size. We now have to use a
      more involved definition of integer promotions and usual arithmetic conversions.
      However, this new definition follows the C standard literally.
      da7a14bb
  20. 10 Oct, 2014 1 commit
  21. 30 Sep, 2014 1 commit
  22. 06 Sep, 2014 1 commit
  23. 22 Aug, 2014 1 commit
    • Robbert Krebbers's avatar
      Modify typing judgments to depend on a description of the types of objects in · 7f9c5994
      Robbert Krebbers authored
      memory instead of the whole memory itself.
      
      This has the following advantages:
      * Avoid parametrization in {addresses,pointers,pointer_bits,bits}.v
      * Make {base_values,values}.v independent of the memory, this makes better
        parallelized compilation possible.
      * Allow small memories (e.g. singletons as used in separation logic) with
        addresses to objects in another part to be typed.
      * Some proofs become easier, because the memory environments are preserved
        under many operations (insert, force, lock, unlock).
      
      It also as the following disadvantages:
      * At all kinds of places we now have explicit casts from memories to memory
        environments. This is kind of ugly. Note, we cannot declare memenv_of as a
        Coercion because it is non-uniform.
      * It is a bit inefficient with respect to the interpreter, because memory
        environments are finite functions instead of proper functions, so calling
        memenv_of often (which we do) is not too good.
      7f9c5994
  24. 10 Jul, 2014 1 commit
  25. 16 Jun, 2014 1 commit
    • Robbert Krebbers's avatar
      Changes in preparation of the C type system and C front-end language · 3503a91f
      Robbert Krebbers authored
      Major changes:
      * Make void a base type, and include a proper void base value. This is necessary
        because expressions (free, functions without return value) can yield a void.
        We now also allow void casts conforming to the C standard.
      * Various missing lemmas about typing, weakening, decidability, ...
      * The operations "free" and "alloc" now operate on l-values instead of r-values.
        This removes some duplication.
      * Improve notations of expressions and statements. Change the presence of the
        operators conforming to the C standard.
      
      Small changes:
      * Use the classes "Typed" and "TypeCheck" for validity of indexes in memory.
        This gives more uniform notations.
      * New tactic "typed_inversion" performs inversion on an inductive predicate
        of type "Typed" and folds the premises.
      * Remove a horrible hack in the definitions of the classes "FMap", "MBind",
        "OMap", "Alter" that was used to let "simpl" behave better. Instead, we have
        defined a tactic "csimpl" that folds the results after performing an
        ordinary "simpl".
      * Fast operation to remove duplicates from lists using hashsets.
      * Make various type constructors (mainly finite map implementations) universe
        polymorphic by packing them into an inductive. This way, the whole C syntax
        can live in type, avoiding the need for (slow) universe checks.
      3503a91f
  26. 05 Jun, 2014 1 commit
    • Robbert Krebbers's avatar
      Preparation to port the master branch · d60affc0
      Robbert Krebbers authored
      Major changes:
      * A data structure to collect locked addresses in memory.
      * Operations to lock and unlock addresses.
      * Remove [ctree_Forall] and express it using [Forall] and [ctree_flatten]. This
        saves a lot of lines of code.
      * Add a [void] value. This value cannot be typed, but will be used as a dummy
        return value for functions with return type [void].
      
      Minor changes:
      * Various deciders in preparation of the executable semantics.
      * Improve naming and notations.
      * Remove obsolete stuff.
      d60affc0
  27. 22 May, 2014 1 commit
    • Robbert Krebbers's avatar
      Various changes. · bb9d75d9
      Robbert Krebbers authored
      * Parametrize refinements with memories. This way, refinements imply typing,
        for example [w1 ⊑{Γ,f@m1↦m2} w2 : τ → (Γ,m1) ⊢ w1 : τ]. This relieves us from
        various hacks.
      * Use addresses instead of index/references pairs for lookup and alter
        operations on memories.
      * Prove various disjointness properties.
      bb9d75d9
  28. 02 May, 2014 2 commits
  29. 12 Aug, 2013 1 commit
    • Robbert Krebbers's avatar
      Finite maps and sets using ordered association lists. · bc659ba4
      Robbert Krebbers authored
      This commit includes the following changes:
      * More theorems about pre-, partial and total orders.
      * Define the lexicographic order on various commonly used data types.
      * Mergesort and its correctness proof.
      * Implement finite maps and sets using ordered association lists.
      bc659ba4
  30. 17 Jun, 2013 1 commit
  31. 15 May, 2013 1 commit
  32. 07 May, 2013 1 commit
    • Robbert Krebbers's avatar
      Lots of refactoring. and new results on permutations and list containment. · 361308c7
      Robbert Krebbers authored
      The refactoring includes:
      * Use infix notations for the various list relations
      * More consistent naming
      * Put lemmas on one line whenever possible
      * Change proofs into one-liners when possible
      * Make better use of the "Implicit Types" command
      * Improve the order of the list module by placing all definitions at the start,
        then the proofs, and finally the tactics.
      
      Besides, there is some new machinery for proofs by reflection on lists. It is
      used for a decision procedure for permutations and list containment.
      361308c7
  33. 19 Feb, 2013 1 commit
    • Robbert Krebbers's avatar
      Support sequence point, add permissions, and update prelude. · 415a4f1c
      Robbert Krebbers authored
      Both the operational and axiomatic semantics are extended with sequence points
      and a permission system based on fractional permissions. In order to achieve
      this, the memory model has been completely revised, and is now built on top
      of an abstract interface for permissions.
      
      Apart from these changed, the library on lists and sets has been heavily
      extended, and minor changed have been made to other parts of the prelude.
      415a4f1c
  34. 09 Jan, 2013 1 commit
  35. 05 Jan, 2013 1 commit
    • Robbert Krebbers's avatar
      Various small changes. · 507a150a
      Robbert Krebbers authored
      * Define the standard strict order on pre orders.
      * Prove that this strict order is well founded for finite sets and finite maps.
        We also provide some utilities to compute with well founded recursion.
      * Improve the "simplify_option_equality" tactic to handle more cases.
      * Axiomatize finiteness of finite maps by translation to lists, instead of by
        them having a finite domain.
      * Prove many additional properties of finite maps.
      * Add many functions and theorems on lists, including: permutations, resize,
        filter, ...
      507a150a
  36. 12 Nov, 2012 1 commit
    • Robbert Krebbers's avatar
      Many relatively small changes. · 50dfc148
      Robbert Krebbers authored
      Most interestingly:
      * Use [lia] instead of [omega] everywhere
      * More many generic lemmas on the memory to the theory on finite maps.
      * Many additional list lemmas.
      * A new interface for a monad for collections, which is now also used by the
        collection tactics.
      * Provide an additional finite collection implementation using unordered lists
        without duplicates removed. This implementation forms a monad (just the list
        monad in disguise).
      50dfc148