C++ ExecutionState::prevPC方法代码示例

void StatsTracker::recordSolverQuery(uint64_t time_stamp, uint64_t solving_time,
    data::QueryReason reason, data::QueryOperation operation,
    bool shadow, const ExecutionState &state) {
  data::SolverQuery *query = currentQuerySet.add_solver_query();

  query->set_time_stamp(time_stamp);
  query->set_solving_time(solving_time);
  query->set_reason(reason);
  query->set_operation(operation);

  KInstruction *ki = state.prevPC();
  executor.kmodule->fillInstructionDebugInfo(
      ki->inst, *query->mutable_debug_info());

  query->set_shadow(shadow);

  data::ExecutionState *es_data = query->mutable_execution_state();
  recordStateUpdate(state, false, false, es_data);
}

void Executor::executeCall(ExecutionState &state,
                           KInstruction *ki,
                           Function *f,
                           std::vector< ref<Expr> > &arguments) {
  fireControlFlowEvent(&state, ::cloud9::worker::CALL);

  if (f && DebugCallHistory) {
    unsigned depth = state.stack().size();

    LOG(INFO) << "Call[" << &state << "]: " << std::string(depth, ' ') << f->getName().str();
  }

  Instruction *i = NULL;
  if (ki)
      i = ki->inst;

  if (ki && f && f->isDeclaration()) {
    switch(f->getIntrinsicID()) {
    case Intrinsic::not_intrinsic:
      // state may be destroyed by this call, cannot touch
      callExternalFunction(state, ki, f, arguments);
      break;

      // va_arg is handled by caller and intrinsic lowering, see comment for
      // ExecutionState::varargs
    case Intrinsic::vastart:  {
      StackFrame &sf = state.stack().back();
      assert(sf.varargs &&
             "vastart called in function with no vararg object");

      // FIXME: This is really specific to the architecture, not the pointer
      // size. This happens to work fir x86-32 and x86-64, however.
      Expr::Width WordSize = Context::get().getPointerWidth();
      if (WordSize == Expr::Int32) {
        executeMemoryOperation(state, true, arguments[0],
                               sf.varargs->getBaseExpr(), 0);
      } else {
        assert(WordSize == Expr::Int64 && "Unknown word size!");

        // X86-64 has quite complicated calling convention. However,
        // instead of implementing it, we can do a simple hack: just
        // make a function believe that all varargs are on stack.
        executeMemoryOperation(state, true, arguments[0],
                               ConstantExpr::create(48, 32), 0); // gp_offset
        executeMemoryOperation(state, true,
                               AddExpr::create(arguments[0],
                                               ConstantExpr::create(4, 64)),
                               ConstantExpr::create(304, 32), 0); // fp_offset
        executeMemoryOperation(state, true,
                               AddExpr::create(arguments[0],
                                               ConstantExpr::create(8, 64)),
                               sf.varargs->getBaseExpr(), 0); // overflow_arg_area
        executeMemoryOperation(state, true,
                               AddExpr::create(arguments[0],
                                               ConstantExpr::create(16, 64)),
                               ConstantExpr::create(0, 64), 0); // reg_save_area
      }
      break;
    }
    case Intrinsic::vaend:
      // va_end is a noop for the interpreter.
      //
      // FIXME: We should validate that the target didn't do something bad
      // with vaeend, however (like call it twice).
      break;

    case Intrinsic::vacopy:
      // va_copy should have been lowered.
      //
      // FIXME: It would be nice to check for errors in the usage of this as
      // well.
    default:
      LOG(FATAL) << "Unknown intrinsic: " << f->getName().data();
    }

    if (InvokeInst *ii = dyn_cast<InvokeInst>(i))
      transferToBasicBlock(ii->getNormalDest(), i->getParent(), state);
  } else {
    // FIXME: I'm not really happy about this reliance on prevPC but it is ok, I
    // guess. This just done to avoid having to pass KInstIterator everywhere
    // instead of the actual instruction, since we can't make a KInstIterator
    // from just an instruction (unlike LLVM).
    KFunction *kf = kmodule->functionMap[f];
    state.pushFrame(state.prevPC(), kf);
    state.pc() = kf->instructions;

    if (statsTracker)
      statsTracker->framePushed(state, &state.stack()[state.stack().size()-2]); //XXX TODO fix this ugly stuff

     // TODO: support "byval" parameter attribute
     // TODO: support zeroext, signext, sret attributes

    unsigned callingArgs = arguments.size();
    unsigned funcArgs = f->arg_size();
    if (!f->isVarArg()) {
      if (callingArgs > funcArgs) {
        LOG(WARNING) << "Calling " << f->getName().data() << " with extra arguments.";
      } else if (callingArgs < funcArgs) {
        terminateStateOnError(state, "calling function with too few arguments",
                              "user.err");
//.........这里部分代码省略.........