7 research outputs found
A semantic foundation for hidden state
We present the first complete soundness proof of the antiframe
rule, a recently proposed proof rule for capturing information hiding
in the presence of higher-order store. Our proof involves solving a
non-trivial recursive domain equation, and it helps identify some of the
key ingredients for soundness
Crowfoot: a verifier for higher-order store programs
We present Crowfoot, an automatic verification tool for imperative programs that manipulate procedures dynamically at runtime; these programs use a heap that can store not only data but also code (commands or procedures). Such heaps are often called higher-order store, and allow for instance the creation of new recursions on the fly. One can use higher-order store to model phenomena such as runtime loading and unloading of code, runtime update of code and runtime code generation. Crowfoot's assertion language, based on separation logic, features nested Hoare triples which describe the behaviour of procedures stored on the heap. The tool addresses complex issues like deep frame rules and recursion through the store, and is the first verification tool based on recent developments in the mathematical foundations of Hoare logics with nested triples
Semantics of Separation-Logic Typing and Higher-order Frame Rules for<br> Algol-like Languages
We show how to give a coherent semantics to programs that are well-specified
in a version of separation logic for a language with higher types: idealized
algol extended with heaps (but with immutable stack variables). In particular,
we provide simple sound rules for deriving higher-order frame rules, allowing
for local reasoning
Semantics of Separation-Logic Typing and Higher-order Frame Rules for Algol-like Languages
We show how to give a coherent semantics to programs that are well-specified
in a version of separation logic for a language with higher types: idealized
algol extended with heaps (but with immutable stack variables). In particular,
we provide simple sound rules for deriving higher-order frame rules, allowing
for local reasoning
Semantics of Separation-Logic Typing and Higher-order Frame Rules for Algol-like Languages
We show how to give a coherent semantics to programs that are well-specifiedin a version of separation logic for a language with higher types: idealizedalgol extended with heaps (but with immutable stack variables). In particular,we provide simple sound rules for deriving higher-order frame rules, allowingfor local reasoning
Nested Hoare Triples and Frame Rules for Higher-order Store
Separation logic is a Hoare-style logic for reasoning about programs with
heap-allocated mutable data structures. As a step toward extending separation
logic to high-level languages with ML-style general (higher-order) storage, we
investigate the compatibility of nested Hoare triples with several variations
of higher-order frame rules. The interaction of nested triples and frame rules
can be subtle, and the inclusion of certain frame rules is in fact unsound. A
particular combination of rules can be shown consistent by means of a Kripke
model where worlds live in a recursively defined ultrametric space. The
resulting logic allows us to elegantly prove programs involving stored code. In
particular, using recursively defined assertions, it leads to natural
specifications and proofs of invariants required for dealing with recursion
through the store.Comment: 42 page