Bug 434839: outparams state explosion on functions with many outparams, r+a=bsmedberg

  // Make sure return value and outparams are never dropped from state.

  for (let bb in cfg_bb_iterator(cfg)) {

    bb.keepVars.add(retvar);

    // retvar is undefined for functions that return void, and

    // adding an undefined to a variable set throws an exception.

    if (retvar != undefined) bb.keepVars.add(retvar);

    for each (let v in outparam_list) {

      bb.keepVars.add(v);

    }

  {

    let trace = TRACE_ESP;

    let fts = link_switches(cfg);

    let a = new OutparamCheck(cfg, psem_list, outparam_list, retvar, retvars, fts, trace);

    for (let i = 0; i < outparam_list.length; ++i) {

      let psem = [ psem_list[i] ];

      let outparam = [ outparam_list[i] ];

      let a = new OutparamCheck(cfg, psem, outparam, retvar, retvars, 

                                fts, trace);

      // This is annoying, but this field is only used for logging anyway.

      a.fndecl = func_decl;

      a.run();

      a.check(decl.resultType == 'void', func_decl);

    }

  }

  if (TRACE_PERF) timer_stop(fstring);

}

  // At this point we know v1 != v2.

  switch (v1) {

  case av.LOCKED:

  case av.UNLOCKED:

    return undefined;

  case av.ZERO:

    return av.intVal(v2) == 0 ? v2 : undefined;

  case av.NONZERO:

    return av.intVal(v2) != 0 ? v2 : undefined;

    // Return a nonempty meet only if the other value is an integer

    // and is nonzero.

    let iv2 = av.intVal(v2);

    return iv2 != undefined && iv2 != 0 ? v2 : undefined;

  default:

    let iv = av.intVal(v1);

    if (iv == 0) return v2 == av.ZERO ? v1 : undefined;