OSMOSE: automatic structural testing of executables

architecture and GAL program. An abstract architectureX is defined by a pairX = 〈R,M〉 where R is a finite set of variables ranging over m-words and M is a finite set of (disjoint) arrays of mwords, called memory regions (shortly, m-regions). Each m-region is indexed by non-negative integer values, called addresses. A memory location (m-loc) is defined as being either a register or the cell of a m-region. The size of m-words stored in each m-loc is fixed a priori for each m-loc. Intuitively, variables represent registers and m-regions represent different physical memories, for example RAM and ROM. A GAL programP is a tupleP = 〈R,M, A, I〉 where 〈R,M〉 is an abstract architecture,A is the set of addresses of valid instructions and I is a map fromA to GAL instructions. GAL instructions are composed of more primitive micro-instructions. Indeed, a GAL instruction is a sequence of data (micro-) instructions followed by a control (micro-) instruction. Data instructions (assign) are multiaffectations. Basic control instructions are static jumps (goto) and dynamic jumps (cgoto). Moreover, these jumps can be combined with a conditional statement (ite). Note that instruction goto is a special case of cgoto, however they are distinguished from each other in GAL since they are managed in very different ways by automatic analysers. GAL instructions obey the following grammar: GAL instr ::= (data) control control ::= jump | ite (cond,jump,jump) jump ::= goto addr | cgoto rhs data ::= assign (lhs1, . . . , lhsn) ← f(rhs1, . . . , rhsn) Copyright c © 2009 John Wiley & Sons, Ltd. Softw. Test. Verif. Reliab. 2009; 0:0–0 Prepared using stvrauth.cls DOI: 10.1002/stvr OSMOSE: AUTOMATIC TESTING OF EXECUTABLES 7