size_t
RiscOperators::add_subdomain(const BaseSemantics::RiscOperatorsPtr &subdomain, const std::string &name, bool activate)
{
assert(subdomain!=NULL);
size_t idx = subdomains.size();
subdomains.push_back(subdomain);
active.push_back(activate);
if (idx>=formatter.subdomain_names.size())
formatter.subdomain_names.resize(idx+1, "");
formatter.subdomain_names[idx] = name;
SValue::promote(get_protoval())->set_subvalue(idx, subdomain->get_protoval());
return idx;
}
explicit State(const BaseSemantics::RiscOperatorsPtr &ops)
: BaseSemantics::RegisterStateGeneric(ops->get_protoval(),
ops->get_state()->get_register_state()->get_register_dictionary()),
ops_(ops) {}
// see base class
bool
SgAsmX86Instruction::isFunctionCallSlow(const std::vector<SgAsmInstruction*>& insns, rose_addr_t *target, rose_addr_t *return_va)
{
if (isFunctionCallFast(insns, target, return_va))
return true;
// The following stuff works only if we have a relatively complete AST.
static const size_t EXECUTION_LIMIT = 10; // max size of basic blocks for expensive analyses
if (insns.empty())
return false;
SgAsmX86Instruction *last = isSgAsmX86Instruction(insns.back());
if (!last)
return false;
SgAsmFunction *func = SageInterface::getEnclosingNode<SgAsmFunction>(last);
SgAsmInterpretation *interp = SageInterface::getEnclosingNode<SgAsmInterpretation>(func);
// Slow method: Emulate the instructions and then look at the EIP and stack. If the EIP points outside the current
// function and the top of the stack holds an address of an instruction within the current function, then this must be a
// function call. FIXME: The implementation here assumes a 32-bit machine. [Robb P. Matzke 2013-09-06]
if (interp && insns.size()<=EXECUTION_LIMIT) {
using namespace rose::BinaryAnalysis;
using namespace rose::BinaryAnalysis::InstructionSemantics2;
using namespace rose::BinaryAnalysis::InstructionSemantics2::SymbolicSemantics;
const InstructionMap &imap = interp->get_instruction_map();
const RegisterDictionary *regdict = RegisterDictionary::dictionary_for_isa(interp);
SMTSolver *solver = NULL; // using a solver would be more accurate, but slower
BaseSemantics::RiscOperatorsPtr ops = RiscOperators::instance(regdict, solver);
DispatcherX86Ptr dispatcher = DispatcherX86::instance(ops);
SValuePtr orig_esp = SValue::promote(ops->readRegister(dispatcher->REG_ESP));
try {
for (size_t i=0; i<insns.size(); ++i)
dispatcher->processInstruction(insns[i]);
} catch (const BaseSemantics::Exception &e) {
return false;
}
// If the next instruction address is concrete but does not point to a function entry point, then this is not a call.
SValuePtr eip = SValue::promote(ops->readRegister(dispatcher->REG_EIP));
if (eip->is_number()) {
rose_addr_t target_va = eip->get_number();
SgAsmFunction *target_func = SageInterface::getEnclosingNode<SgAsmFunction>(imap.get_value_or(target_va, NULL));
if (!target_func || target_va!=target_func->get_entry_va())
return false;
}
// If nothing was pushed onto the stack, then this isn't a function call.
SValuePtr esp = SValue::promote(ops->readRegister(dispatcher->REG_ESP));
SValuePtr stack_delta = SValue::promote(ops->add(esp, ops->negate(orig_esp)));
SValuePtr stack_delta_sign = SValue::promote(ops->extract(stack_delta, 31, 32));
if (stack_delta_sign->is_number() && 0==stack_delta_sign->get_number())
return false;
// If the top of the stack does not contain a concrete value or the top of the stack does not point to an instruction
// in this basic block's function, then this is not a function call.
SValuePtr top = SValue::promote(ops->readMemory(dispatcher->REG_SS, esp, esp->undefined_(32), esp->boolean_(true)));
if (top->is_number()) {
rose_addr_t va = top->get_number();
SgAsmFunction *return_func = SageInterface::getEnclosingNode<SgAsmFunction>(imap.get_value_or(va, NULL));
if (!return_func || return_func!=func) {
return false;
}
} else {
return false;
}
// Since EIP might point to a function entry address and since the top of the stack contains a pointer to an
// instruction in this function, we assume that this is a function call.
if (target && eip->is_number())
*target = eip->get_number();
if (return_va && top->is_number())
*return_va = top->get_number();
return true;
}
// Similar to the above method, but works when all we have is the basic block (e.g., this case gets hit quite a bit from
// the Partitioner). Returns true if, after executing the basic block, the top of the stack contains the fall-through
// address of the basic block. We depend on our caller to figure out if EIP is reasonably a function entry address.
if (!interp && insns.size()<=EXECUTION_LIMIT) {
using namespace rose::BinaryAnalysis;
using namespace rose::BinaryAnalysis::InstructionSemantics2;
using namespace rose::BinaryAnalysis::InstructionSemantics2::SymbolicSemantics;
const RegisterDictionary *regdict = RegisterDictionary::dictionary_pentium4();
SMTSolver *solver = NULL; // using a solver would be more accurate, but slower
BaseSemantics::RiscOperatorsPtr ops = RiscOperators::instance(regdict, solver);
DispatcherX86Ptr dispatcher = DispatcherX86::instance(ops);
try {
for (size_t i=0; i<insns.size(); ++i)
dispatcher->processInstruction(insns[i]);
} catch (const BaseSemantics::Exception &e) {
return false;
}
// Look at the top of the stack
SValuePtr top = SValue::promote(ops->readMemory(dispatcher->REG_SS, ops->readRegister(dispatcher->REG_ESP),
ops->get_protoval()->undefined_(32),
ops->get_protoval()->boolean_(true)));
if (top->is_number() && top->get_number() == last->get_address()+last->get_size()) {
if (target) {
SValuePtr eip = SValue::promote(ops->readRegister(dispatcher->REG_EIP));
if (eip->is_number())
*target = eip->get_number();
}
if (return_va)
*return_va = top->get_number();
return true;
}
}
return false;
}
