/*

 * Copyright 2000-2008 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 *

 */

#include "incls/_precompiled.incl"

#include "incls/_callGenerator.cpp.incl"

CallGenerator::CallGenerator(ciMethod* method) {

  _method = method;

}

// Utility function.

const TypeFunc* CallGenerator::tf() const {

  return TypeFunc::make(method());

}

//-----------------------------ParseGenerator---------------------------------

// Internal class which handles all direct bytecode traversal.

class ParseGenerator : public InlineCallGenerator {

private:

  bool  _is_osr;

  float _expected_uses;

public:

  ParseGenerator(ciMethod* method, float expected_uses, bool is_osr = false)

    : InlineCallGenerator(method)

  {

    _is_osr        = is_osr;

    _expected_uses = expected_uses;

    assert(can_parse(method, is_osr), "parse must be possible");

  }

  // Can we build either an OSR or a regular parser for this method?

  static bool can_parse(ciMethod* method, int is_osr = false);

  virtual bool      is_parse() const           { return true; }

  virtual JVMState* generate(JVMState* jvms);

  int is_osr() { return _is_osr; }

};

JVMState* ParseGenerator::generate(JVMState* jvms) {

  Compile* C = Compile::current();

  if (is_osr()) {

    // The JVMS for a OSR has a single argument (see its TypeFunc).

    assert(jvms->depth() == 1, "no inline OSR");

  }

  if (C->failing()) {

    return NULL;  // bailing out of the compile; do not try to parse

  }

  Parse parser(jvms, method(), _expected_uses);

  // Grab signature for matching/allocation

#ifdef ASSERT

  if (parser.tf() != (parser.depth() == 1 ? C->tf() : tf())) {

    MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);

    assert(C->env()->system_dictionary_modification_counter_changed(),

           "Must invalidate if TypeFuncs differ");

  }

#endif

  GraphKit& exits = parser.exits();

  if (C->failing()) {

    while (exits.pop_exception_state() != NULL) ;

    return NULL;

  }

  assert(exits.jvms()->same_calls_as(jvms), "sanity");

  // Simply return the exit state of the parser,

  // augmented by any exceptional states.

  return exits.transfer_exceptions_into_jvms();

}

//---------------------------DirectCallGenerator------------------------------

// Internal class which handles all out-of-line calls w/o receiver type checks.

class DirectCallGenerator : public CallGenerator {

public:

  DirectCallGenerator(ciMethod* method)

    : CallGenerator(method)

  {

  }

  virtual JVMState* generate(JVMState* jvms);

};

JVMState* DirectCallGenerator::generate(JVMState* jvms) {

  GraphKit kit(jvms);

  bool is_static = method()->is_static();

  address target = is_static ? SharedRuntime::get_resolve_static_call_stub()

                             : SharedRuntime::get_resolve_opt_virtual_call_stub();

  if (kit.C->log() != NULL) {

    kit.C->log()->elem("direct_call bci='%d'", jvms->bci());

  }

  CallStaticJavaNode *call = new (kit.C, tf()->domain()->cnt()) CallStaticJavaNode(tf(), target, method(), kit.bci());

  if (!is_static) {

    // Make an explicit receiver null_check as part of this call.

    // Since we share a map with the caller, his JVMS gets adjusted.

    kit.null_check_receiver(method());

    if (kit.stopped()) {

      // And dump it back to the caller, decorated with any exceptions:

      return kit.transfer_exceptions_into_jvms();

    }

    // Mark the call node as virtual, sort of:

    call->set_optimized_virtual(true);

  }

  kit.set_arguments_for_java_call(call);

  kit.set_edges_for_java_call(call);

  Node* ret = kit.set_results_for_java_call(call);

  kit.push_node(method()->return_type()->basic_type(), ret);

  return kit.transfer_exceptions_into_jvms();

}

class VirtualCallGenerator : public CallGenerator {

private:

  int _vtable_index;

public:

  VirtualCallGenerator(ciMethod* method, int vtable_index)

    : CallGenerator(method), _vtable_index(vtable_index)

  {

    assert(vtable_index == methodOopDesc::invalid_vtable_index ||

           vtable_index >= 0, "either invalid or usable");

  }

  virtual bool      is_virtual() const          { return true; }

  virtual JVMState* generate(JVMState* jvms);

};

//--------------------------VirtualCallGenerator------------------------------

// Internal class which handles all out-of-line calls checking receiver type.

JVMState* VirtualCallGenerator::generate(JVMState* jvms) {

  GraphKit kit(jvms);

  Node* receiver = kit.argument(0);

  if (kit.C->log() != NULL) {

    kit.C->log()->elem("virtual_call bci='%d'", jvms->bci());

  }

  // If the receiver is a constant null, do not torture the system

  // by attempting to call through it.  The compile will proceed

  // correctly, but may bail out in final_graph_reshaping, because

  // the call instruction will have a seemingly deficient out-count.

  // (The bailout says something misleading about an "infinite loop".)

  if (kit.gvn().type(receiver)->higher_equal(TypePtr::NULL_PTR)) {

    kit.inc_sp(method()->arg_size());  // restore arguments

    kit.uncommon_trap(Deoptimization::Reason_null_check,

                      Deoptimization::Action_none,

                      NULL, "null receiver");

    return kit.transfer_exceptions_into_jvms();

  }

  // Ideally we would unconditionally do a null check here and let it

  // be converted to an implicit check based on profile information.

  // However currently the conversion to implicit null checks in

  // Block::implicit_null_check() only looks for loads and stores, not calls.

  ciMethod *caller = kit.method();

  ciMethodData *caller_md = (caller == NULL) ? NULL : caller->method_data();

  if (!UseInlineCaches || !ImplicitNullChecks ||

       ((ImplicitNullCheckThreshold > 0) && caller_md &&

       (caller_md->trap_count(Deoptimization::Reason_null_check)

       >= (uint)ImplicitNullCheckThreshold))) {

    // Make an explicit receiver null_check as part of this call.

    // Since we share a map with the caller, his JVMS gets adjusted.

    receiver = kit.null_check_receiver(method());

    if (kit.stopped()) {

      // And dump it back to the caller, decorated with any exceptions:

      return kit.transfer_exceptions_into_jvms();

    }

  }

  assert(!method()->is_static(), "virtual call must not be to static");

  assert(!method()->is_final(), "virtual call should not be to final");

  assert(!method()->is_private(), "virtual call should not be to private");

  assert(_vtable_index == methodOopDesc::invalid_vtable_index || !UseInlineCaches,

         "no vtable calls if +UseInlineCaches ");

  address target = SharedRuntime::get_resolve_virtual_call_stub();

  // Normal inline cache used for call

  CallDynamicJavaNode *call = new (kit.C, tf()->domain()->cnt()) CallDynamicJavaNode(tf(), target, method(), _vtable_index, kit.bci());

  kit.set_arguments_for_java_call(call);

  kit.set_edges_for_java_call(call);

  Node* ret = kit.set_results_for_java_call(call);

  kit.push_node(method()->return_type()->basic_type(), ret);

  // Represent the effect of an implicit receiver null_check

  // as part of this call.  Since we share a map with the caller,

  // his JVMS gets adjusted.

  kit.cast_not_null(receiver);

  return kit.transfer_exceptions_into_jvms();

}

bool ParseGenerator::can_parse(ciMethod* m, int entry_bci) {

  // Certain methods cannot be parsed at all:

  if (!m->can_be_compiled())              return false;

  if (!m->has_balanced_monitors())        return false;

  if (m->get_flow_analysis()->failing())  return false;

  // (Methods may bail out for other reasons, after the parser is run.

  // We try to avoid this, but if forced, we must return (Node*)NULL.

  // The user of the CallGenerator must check for this condition.)

  return true;

}

CallGenerator* CallGenerator::for_inline(ciMethod* m, float expected_uses) {

  if (!ParseGenerator::can_parse(m))  return NULL;

  return new ParseGenerator(m, expected_uses);

}

// As a special case, the JVMS passed to this CallGenerator is

// for the method execution already in progress, not just the JVMS

// of the caller.  Thus, this CallGenerator cannot be mixed with others!

CallGenerator* CallGenerator::for_osr(ciMethod* m, int osr_bci) {

  if (!ParseGenerator::can_parse(m, true))  return NULL;

  float past_uses = m->interpreter_invocation_count();

  float expected_uses = past_uses;

  return new ParseGenerator(m, expected_uses, true);

}

CallGenerator* CallGenerator::for_direct_call(ciMethod* m) {

  assert(!m->is_abstract(), "for_direct_call mismatch");

  return new DirectCallGenerator(m);

}

CallGenerator* CallGenerator::for_virtual_call(ciMethod* m, int vtable_index) {

  assert(!m->is_static(), "for_virtual_call mismatch");

  return new VirtualCallGenerator(m, vtable_index);

}

//---------------------------WarmCallGenerator--------------------------------

// Internal class which handles initial deferral of inlining decisions.

class WarmCallGenerator : public CallGenerator {

  WarmCallInfo*   _call_info;

  CallGenerator*  _if_cold;

  CallGenerator*  _if_hot;

  bool            _is_virtual;   // caches virtuality of if_cold

  bool            _is_inline;    // caches inline-ness of if_hot

public:

  WarmCallGenerator(WarmCallInfo* ci,

                    CallGenerator* if_cold,

                    CallGenerator* if_hot)

    : CallGenerator(if_cold->method())

  {

    assert(method() == if_hot->method(), "consistent choices");

    _call_info  = ci;

    _if_cold    = if_cold;

    _if_hot     = if_hot;

    _is_virtual = if_cold->is_virtual();

    _is_inline  = if_hot->is_inline();

  }

  virtual bool      is_inline() const           { return _is_inline; }

  virtual bool      is_virtual() const          { return _is_virtual; }

  virtual bool      is_deferred() const         { return true; }

  virtual JVMState* generate(JVMState* jvms);

};

CallGenerator* CallGenerator::for_warm_call(WarmCallInfo* ci,

                                            CallGenerator* if_cold,

                                            CallGenerator* if_hot) {

  return new WarmCallGenerator(ci, if_cold, if_hot);

}

JVMState* WarmCallGenerator::generate(JVMState* jvms) {

  Compile* C = Compile::current();

  if (C->log() != NULL) {

    C->log()->elem("warm_call bci='%d'", jvms->bci());

  }

  jvms = _if_cold->generate(jvms);

  if (jvms != NULL) {

    Node* m = jvms->map()->control();

    if (m->is_CatchProj()) m = m->in(0);  else m = C->top();

    if (m->is_Catch())     m = m->in(0);  else m = C->top();

    if (m->is_Proj())      m = m->in(0);  else m = C->top();

    if (m->is_CallJava()) {

      _call_info->set_call(m->as_Call());

      _call_info->set_hot_cg(_if_hot);

#ifndef PRODUCT

      if (PrintOpto || PrintOptoInlining) {

        tty->print_cr("Queueing for warm inlining at bci %d:", jvms->bci());

        tty->print("WCI: ");

        _call_info->print();

      }

#endif

      _call_info->set_heat(_call_info->compute_heat());

      C->set_warm_calls(_call_info->insert_into(C->warm_calls()));

    }

  }

  return jvms;

}

void WarmCallInfo::make_hot() {

  Compile* C = Compile::current();

  // Replace the callnode with something better.

  CallJavaNode* call = this->call()->as_CallJava();

  ciMethod* method   = call->method();

  int       nargs    = method->arg_size();

  JVMState* jvms     = call->jvms()->clone_shallow(C);

  uint size = TypeFunc::Parms + MAX2(2, nargs);

  SafePointNode* map = new (C, size) SafePointNode(size, jvms);

  for (uint i1 = 0; i1 < (uint)(TypeFunc::Parms + nargs); i1++) {

    map->init_req(i1, call->in(i1));

  }

  jvms->set_map(map);

  jvms->set_offsets(map->req());

  jvms->set_locoff(TypeFunc::Parms);

  jvms->set_stkoff(TypeFunc::Parms);

  GraphKit kit(jvms);

  JVMState* new_jvms = _hot_cg->generate(kit.jvms());

  if (new_jvms == NULL)  return;  // no change

  if (C->failing())      return;

  kit.set_jvms(new_jvms);

  Node* res = C->top();

  int   res_size = method->return_type()->size();

  if (res_size != 0) {

    kit.inc_sp(-res_size);

    res = kit.argument(0);

  }

  GraphKit ekit(kit.combine_and_pop_all_exception_states()->jvms());

  // Replace the call:

  for (DUIterator i = call->outs(); call->has_out(i); i++) {

    Node* n = call->out(i);

    Node* nn = NULL;  // replacement

    if (n->is_Proj()) {

      ProjNode* nproj = n->as_Proj();

      assert(nproj->_con < (uint)(TypeFunc::Parms + (res_size ? 1 : 0)), "sane proj");

      if (nproj->_con == TypeFunc::Parms) {

        nn = res;

      } else {

        nn = kit.map()->in(nproj->_con);

      }

      if (nproj->_con == TypeFunc::I_O) {

        for (DUIterator j = nproj->outs(); nproj->has_out(j); j++) {

          Node* e = nproj->out(j);

          if (e->Opcode() == Op_CreateEx) {

            e->replace_by(ekit.argument(0));

          } else if (e->Opcode() == Op_Catch) {

            for (DUIterator k = e->outs(); e->has_out(k); k++) {

              CatchProjNode* p = e->out(j)->as_CatchProj();

              if (p->is_handler_proj()) {

                p->replace_by(ekit.control());

              } else {

                p->replace_by(kit.control());

              }

            }

          }

        }

      }

    }

    NOT_PRODUCT(if (!nn)  n->dump(2));

    assert(nn != NULL, "don't know what to do with this user");

    n->replace_by(nn);

  }

}

void WarmCallInfo::make_cold() {

  // No action:  Just dequeue.

}

//------------------------PredictedCallGenerator------------------------------

// Internal class which handles all out-of-line calls checking receiver type.

class PredictedCallGenerator : public CallGenerator {

  ciKlass*       _predicted_receiver;

  CallGenerator* _if_missed;

  CallGenerator* _if_hit;

  float          _hit_prob;

public:

  PredictedCallGenerator(ciKlass* predicted_receiver,

                         CallGenerator* if_missed,

                         CallGenerator* if_hit, float hit_prob)

    : CallGenerator(if_missed->method())

  {

    // The call profile data may predict the hit_prob as extreme as 0 or 1.

    // Remove the extremes values from the range.

    if (hit_prob > PROB_MAX)   hit_prob = PROB_MAX;

    if (hit_prob < PROB_MIN)   hit_prob = PROB_MIN;

    _predicted_receiver = predicted_receiver;

    _if_missed          = if_missed;

    _if_hit             = if_hit;

    _hit_prob           = hit_prob;

  }

  virtual bool      is_virtual()   const    { return true; }

  virtual bool      is_inline()    const    { return _if_hit->is_inline(); }

  virtual bool      is_deferred()  const    { return _if_hit->is_deferred(); }

  virtual JVMState* generate(JVMState* jvms);

};

CallGenerator* CallGenerator::for_predicted_call(ciKlass* predicted_receiver,

                                                 CallGenerator* if_missed,

                                                 CallGenerator* if_hit,

                                                 float hit_prob) {

  return new PredictedCallGenerator(predicted_receiver, if_missed, if_hit, hit_prob);

}

JVMState* PredictedCallGenerator::generate(JVMState* jvms) {

  GraphKit kit(jvms);

  PhaseGVN& gvn = kit.gvn();

  // We need an explicit receiver null_check before checking its type.

  // We share a map with the caller, so his JVMS gets adjusted.

  Node* receiver = kit.argument(0);

  CompileLog* log = kit.C->log();

  if (log != NULL) {

    log->elem("predicted_call bci='%d' klass='%d'",

              jvms->bci(), log->identify(_predicted_receiver));

  }

  receiver = kit.null_check_receiver(method());

  if (kit.stopped()) {

    return kit.transfer_exceptions_into_jvms();

  }

  Node* exact_receiver = receiver;  // will get updated in place...

  Node* slow_ctl = kit.type_check_receiver(receiver,

                                           _predicted_receiver, _hit_prob,

                                           &exact_receiver);

  SafePointNode* slow_map = NULL;

  JVMState* slow_jvms;

  { PreserveJVMState pjvms(&kit);

    kit.set_control(slow_ctl);

    if (!kit.stopped()) {

      slow_jvms = _if_missed->generate(kit.sync_jvms());

      assert(slow_jvms != NULL, "miss path must not fail to generate");

      kit.add_exception_states_from(slow_jvms);

      kit.set_map(slow_jvms->map());

      if (!kit.stopped())

        slow_map = kit.stop();

    }

  }

  if (kit.stopped()) {

    // Instance exactly does not matches the desired type.

    kit.set_jvms(slow_jvms);

    return kit.transfer_exceptions_into_jvms();

  }

  // fall through if the instance exactly matches the desired type

  kit.replace_in_map(receiver, exact_receiver);

  // Make the hot call:

  JVMState* new_jvms = _if_hit->generate(kit.sync_jvms());

  if (new_jvms == NULL) {

    // Inline failed, so make a direct call.

    assert(_if_hit->is_inline(), "must have been a failed inline");

    CallGenerator* cg = CallGenerator::for_direct_call(_if_hit->method());

    new_jvms = cg->generate(kit.sync_jvms());

  }

  kit.add_exception_states_from(new_jvms);

  kit.set_jvms(new_jvms);

  // Need to merge slow and fast?

  if (slow_map == NULL) {

    // The fast path is the only path remaining.

    return kit.transfer_exceptions_into_jvms();

  }

  if (kit.stopped()) {

    // Inlined method threw an exception, so it's just the slow path after all.

    kit.set_jvms(slow_jvms);

    return kit.transfer_exceptions_into_jvms();

  }

  // Finish the diamond.

  kit.C->set_has_split_ifs(true); // Has chance for split-if optimization

  RegionNode* region = new (kit.C, 3) RegionNode(3);

  region->init_req(1, kit.control());

  region->init_req(2, slow_map->control());

  kit.set_control(gvn.transform(region));

  Node* iophi = PhiNode::make(region, kit.i_o(), Type::ABIO);

  iophi->set_req(2, slow_map->i_o());

  kit.set_i_o(gvn.transform(iophi));

  kit.merge_memory(slow_map->merged_memory(), region, 2);

  uint tos = kit.jvms()->stkoff() + kit.sp();

  uint limit = slow_map->req();

  for (uint i = TypeFunc::Parms; i < limit; i++) {

    // Skip unused stack slots; fast forward to monoff();

    if (i == tos) {

      i = kit.jvms()->monoff();

      if( i >= limit ) break;

    }

    Node* m = kit.map()->in(i);

    Node* n = slow_map->in(i);

    if (m != n) {

      const Type* t = gvn.type(m)->meet(gvn.type(n));

      Node* phi = PhiNode::make(region, m, t);

      phi->set_req(2, n);

      kit.map()->set_req(i, gvn.transform(phi));

    }

  }

  return kit.transfer_exceptions_into_jvms();

}