C++ SafePointNode::init_req方法代码示例

void LateInlineCallGenerator::do_late_inline() {
  // Can't inline it
  CallStaticJavaNode* call = call_node();
  if (call == NULL || call->outcnt() == 0 ||
      call->in(0) == NULL || call->in(0)->is_top()) {
    return;
  }

  const TypeTuple *r = call->tf()->domain();
  for (int i1 = 0; i1 < method()->arg_size(); i1++) {
    if (call->in(TypeFunc::Parms + i1)->is_top() && r->field_at(TypeFunc::Parms + i1) != Type::HALF) {
      assert(Compile::current()->inlining_incrementally(), "shouldn't happen during parsing");
      return;
    }
  }

  if (call->in(TypeFunc::Memory)->is_top()) {
    assert(Compile::current()->inlining_incrementally(), "shouldn't happen during parsing");
    return;
  }

  Compile* C = Compile::current();
  // Remove inlined methods from Compiler's lists.
  if (call->is_macro()) {
    C->remove_macro_node(call);
  }

  // Make a clone of the JVMState that appropriate to use for driving a parse
  JVMState* old_jvms = call->jvms();
  JVMState* jvms = old_jvms->clone_shallow(C);
  uint size = call->req();
  SafePointNode* map = new (C) SafePointNode(size, jvms);
  for (uint i1 = 0; i1 < size; i1++) {
    map->init_req(i1, call->in(i1));
  }

  // Make sure the state is a MergeMem for parsing.
  if (!map->in(TypeFunc::Memory)->is_MergeMem()) {
    Node* mem = MergeMemNode::make(C, map->in(TypeFunc::Memory));
    C->initial_gvn()->set_type_bottom(mem);
    map->set_req(TypeFunc::Memory, mem);
  }

  uint nargs = method()->arg_size();
  // blow away old call arguments
  Node* top = C->top();
  for (uint i1 = 0; i1 < nargs; i1++) {
    map->set_req(TypeFunc::Parms + i1, top);
  }
  jvms->set_map(map);

  // Make enough space in the expression stack to transfer
  // the incoming arguments and return value.
  map->ensure_stack(jvms, jvms->method()->max_stack());
  for (uint i1 = 0; i1 < nargs; i1++) {
    map->set_argument(jvms, i1, call->in(TypeFunc::Parms + i1));
  }

  // This check is done here because for_method_handle_inline() method
  // needs jvms for inlined state.
  if (!do_late_inline_check(jvms)) {
    map->disconnect_inputs(NULL, C);
    return;
  }

  C->print_inlining_insert(this);

  CompileLog* log = C->log();
  if (log != NULL) {
    log->head("late_inline method='%d'", log->identify(method()));
    JVMState* p = jvms;
    while (p != NULL) {
      log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method()));
      p = p->caller();
    }
    log->tail("late_inline");
  }

  // Setup default node notes to be picked up by the inlining
  Node_Notes* old_nn = C->default_node_notes();
  if (old_nn != NULL) {
    Node_Notes* entry_nn = old_nn->clone(C);
    entry_nn->set_jvms(jvms);
    C->set_default_node_notes(entry_nn);
  }

  // Now perform the inling using the synthesized JVMState
  JVMState* new_jvms = _inline_cg->generate(jvms, NULL);
  if (new_jvms == NULL)  return;  // no change
  if (C->failing())      return;

  // Capture any exceptional control flow
  GraphKit kit(new_jvms);

  // Find the result object
  Node* result = C->top();
  int   result_size = method()->return_type()->size();
  if (result_size != 0 && !kit.stopped()) {
    result = (result_size == 1) ? kit.pop() : kit.pop_pair();
  }
//.........这里部分代码省略.........

void LateInlineCallGenerator::do_late_inline() {
  // Can't inline it
  if (call_node() == NULL || call_node()->outcnt() == 0 ||
      call_node()->in(0) == NULL || call_node()->in(0)->is_top())
    return;

  CallStaticJavaNode* call = call_node();

  // Make a clone of the JVMState that appropriate to use for driving a parse
  Compile* C = Compile::current();
  JVMState* jvms     = call->jvms()->clone_shallow(C);
  uint size = call->req();
  SafePointNode* map = new (C, size) SafePointNode(size, jvms);
  for (uint i1 = 0; i1 < size; i1++) {
    map->init_req(i1, call->in(i1));
  }

  // Make sure the state is a MergeMem for parsing.
  if (!map->in(TypeFunc::Memory)->is_MergeMem()) {
    map->set_req(TypeFunc::Memory, MergeMemNode::make(C, map->in(TypeFunc::Memory)));
  }

  // Make enough space for the expression stack and transfer the incoming arguments
  int nargs    = method()->arg_size();
  jvms->set_map(map);
  map->ensure_stack(jvms, jvms->method()->max_stack());
  if (nargs > 0) {
    for (int i1 = 0; i1 < nargs; i1++) {
      map->set_req(i1 + jvms->argoff(), call->in(TypeFunc::Parms + i1));
    }
  }

  CompileLog* log = C->log();
  if (log != NULL) {
    log->head("late_inline method='%d'", log->identify(method()));
    JVMState* p = jvms;
    while (p != NULL) {
      log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method()));
      p = p->caller();
    }
    log->tail("late_inline");
  }

  // Setup default node notes to be picked up by the inlining
  Node_Notes* old_nn = C->default_node_notes();
  if (old_nn != NULL) {
    Node_Notes* entry_nn = old_nn->clone(C);
    entry_nn->set_jvms(jvms);
    C->set_default_node_notes(entry_nn);
  }

  // Now perform the inling using the synthesized JVMState
  JVMState* new_jvms = _inline_cg->generate(jvms);
  if (new_jvms == NULL)  return;  // no change
  if (C->failing())      return;

  // Capture any exceptional control flow
  GraphKit kit(new_jvms);

  // Find the result object
  Node* result = C->top();
  int   result_size = method()->return_type()->size();
  if (result_size != 0 && !kit.stopped()) {
    result = (result_size == 1) ? kit.pop() : kit.pop_pair();
  }

  kit.replace_call(call, result);
}