Liqian Chen

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We introduce a new numerical abstract domain, so-called interval polyhedra (itvPol), to infer and propagate interval linear constraints over program variables. itvPol, which allows to represent constraints of the form k [a k , b k ]x k ≤ c, is more expressive than the classic convex polyhedra domain and allows to express certain non-convex (even(More)
The polyhedra abstract domain is one of the most powerful and commonly used numerical abstract domains in the field of static program analysis based on abstract interpretation. In this paper, we present an implementation of the polyhedra domain using floating-point arithmetic without sacrificing sound-ness. Floating-point arithmetic allows a compact memory(More)
We introduce a new abstract domain, namely the domain of Interval Linear Equalities (itvLinEqs), which generalizes the affine equality domain with interval coefficients by leveraging results from interval linear algebra. The representation of itvLinEqs is based on a row echelon system of interval linear equalities , which natively allows expressing(More)
In Cyber-Physical Systems with interrupt mechanism, interrupts may cause unexpected interleaving executions and even wrong execution results. A kind of frequently occurred errors are caused by data race. We present an approach under the framework of bounded model checking (BMC) to detect data race for interrupt driven programs. The key idea is to(More)
Linear relation analysis (polyhedral analysis), devoted to discovering linear invariant relations among variables of a program, remains one of the most powerful abstract interpretations but is subject to convexity limitations. Absolute value enjoys piecewise linear expressiveness and thus natively fits to encode certain non-convex properties. Based on this(More)
While the definition of the revised widening for polyhedra is defined in terms of inequalities, most implementations use the double description method as a means to an efficient implementation. We show how standard widening can be implemented in a simple and efficient way using a normalized H-representation (constraint-only) which has become popular in(More)
The octagon abstract domain, devoted to discovering octagonal constraints (also called Unit Two Variable Per Inequality or UTVPI constraints) of a program, is one of the most commonly used numerical abstractions in practice, due to its quadratic memory complexity and cubic time complexity. However, the octagon domain itself is restricted to express convex(More)
Scavenger receptor A (SRA) is expressed predominantly in phagocytic cells playing an essential role in the host immune defense against invading microorganisms. Our previous study reported the presence of SRA in a soluble form in patients with infection of hepatitis B viruses (HBV). However, the association of soluble SRA with stages of HBV infection and the(More)
Embedded software often involves intensive numerical computations and thus can contain a number of numerical run-time errors. The technique of numerical static analysis is of practical importance for checking the correctness of embedded software. However, most of the existing approaches of numerical static analysis consider sequential programs, while(More)
OBJECTIVE Protective ventilation (PV) has been validated in patients with acute respiratory distress syndrome. However, the effect of PV in patients undergoing major surgery is controversial. The study aimed to explore the beneficial effect of PV on patients undergoing a major operation by systematic review and meta-analysis. SETTING Various levels of(More)