/*

 * Copyright (c) 2000, 2019, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "ci/bcEscapeAnalyzer.hpp"

#include "ci/ciCallSite.hpp"

#include "ci/ciObjArray.hpp"

#include "ci/ciMemberName.hpp"

#include "ci/ciMethodHandle.hpp"

#include "classfile/javaClasses.hpp"

#include "compiler/compileLog.hpp"

#include "opto/addnode.hpp"

#include "opto/callGenerator.hpp"

#include "opto/callnode.hpp"

#include "opto/castnode.hpp"

#include "opto/cfgnode.hpp"

#include "opto/parse.hpp"

#include "opto/rootnode.hpp"

#include "opto/runtime.hpp"

#include "opto/subnode.hpp"

#include "runtime/sharedRuntime.hpp"

// Utility function.

const TypeFunc* CallGenerator::tf() const {

  return TypeFunc::make(method());

}

bool CallGenerator::is_inlined_method_handle_intrinsic(JVMState* jvms, ciMethod* m) {

  return is_inlined_method_handle_intrinsic(jvms->method(), jvms->bci(), m);

}

bool CallGenerator::is_inlined_method_handle_intrinsic(ciMethod* caller, int bci, ciMethod* m) {

  ciMethod* symbolic_info = caller->get_method_at_bci(bci);

  return is_inlined_method_handle_intrinsic(symbolic_info, m);

}

bool CallGenerator::is_inlined_method_handle_intrinsic(ciMethod* symbolic_info, ciMethod* m) {

  return symbolic_info->is_method_handle_intrinsic() && !m->is_method_handle_intrinsic();

}

//-----------------------------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(InlineTree::check_can_parse(method) == NULL, "parse must be possible");

  }

  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();

  C->print_inlining_update(this);

  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

  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 {

 private:

  CallStaticJavaNode* _call_node;

  // Force separate memory and I/O projections for the exceptional

  // paths to facilitate late inlinig.

  bool                _separate_io_proj;

 public:

  DirectCallGenerator(ciMethod* method, bool separate_io_proj)

    : CallGenerator(method),

      _separate_io_proj(separate_io_proj)

  {

  }

  virtual JVMState* generate(JVMState* jvms);

  CallStaticJavaNode* call_node() const { return _call_node; }

};

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

  GraphKit kit(jvms);

  kit.C->print_inlining_update(this);

  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 CallStaticJavaNode(kit.C, tf(), target, method(), kit.bci());

  if (is_inlined_method_handle_intrinsic(jvms, method())) {

    // To be able to issue a direct call and skip a call to MH.linkTo*/invokeBasic adapter,

    // additional information about the method being invoked should be attached

    // to the call site to make resolution logic work

    // (see SharedRuntime::resolve_static_call_C).

    call->set_override_symbolic_info(true);

  }

  _call_node = call;  // Save the call node in case we need it later

  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_before_call(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);

    if (method()->is_method_handle_intrinsic() ||

        method()->is_compiled_lambda_form()) {

      call->set_method_handle_invoke(true);

    }

  }

  kit.set_arguments_for_java_call(call);

  kit.set_edges_for_java_call(call, false, _separate_io_proj);

  Node* ret = kit.set_results_for_java_call(call, _separate_io_proj);

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

  return kit.transfer_exceptions_into_jvms();

}

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

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

class VirtualCallGenerator : public CallGenerator {

private:

  int _vtable_index;

public:

  VirtualCallGenerator(ciMethod* method, int vtable_index)

    : CallGenerator(method), _vtable_index(vtable_index)

  {

    assert(vtable_index == Method::invalid_vtable_index ||

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

  }

  virtual bool      is_virtual() const          { return true; }

  virtual JVMState* generate(JVMState* jvms);

};

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

  GraphKit kit(jvms);

  Node* receiver = kit.argument(0);

  kit.C->print_inlining_update(this);

  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)) {

    assert(Bytecodes::is_invoke(kit.java_bc()), "%d: %s", kit.java_bc(), Bytecodes::name(kit.java_bc()));

    ciMethod* declared_method = kit.method()->get_method_at_bci(kit.bci());

    int arg_size = declared_method->signature()->arg_size_for_bc(kit.java_bc());

    kit.inc_sp(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 || !os::zero_page_read_protected() ||

       ((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_before_call(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 == Method::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 CallDynamicJavaNode(tf(), target, method(), _vtable_index, kit.bci());

  if (is_inlined_method_handle_intrinsic(jvms, method())) {

    // To be able to issue a direct call (optimized virtual or virtual)

    // and skip a call to MH.linkTo*/invokeBasic adapter, additional information

    // about the method being invoked should be attached to the call site to

    // make resolution logic work (see SharedRuntime::resolve_{virtual,opt_virtual}_call_C).

    call->set_override_symbolic_info(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);

  // 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();

}

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

  if (InlineTree::check_can_parse(m) != NULL)  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 (InlineTree::check_can_parse(m) != NULL)  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, bool separate_io_proj) {

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

  return new DirectCallGenerator(m, separate_io_proj);

}

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

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

  assert(!m->is_method_handle_intrinsic(), "should be a direct call");

  return new VirtualCallGenerator(m, vtable_index);

}

// Allow inlining decisions to be delayed

class LateInlineCallGenerator : public DirectCallGenerator {

 private:

  jlong _unique_id;   // unique id for log compilation

  bool _is_pure_call; // a hint that the call doesn't have important side effects to care about

 protected:

  CallGenerator* _inline_cg;

  virtual bool do_late_inline_check(JVMState* jvms) { return true; }

 public:

  LateInlineCallGenerator(ciMethod* method, CallGenerator* inline_cg, bool is_pure_call = false) :

    DirectCallGenerator(method, true), _unique_id(0), _is_pure_call(is_pure_call), _inline_cg(inline_cg) {}

  virtual bool is_late_inline() const { return true; }

  // Convert the CallStaticJava into an inline

  virtual void do_late_inline();

  virtual JVMState* generate(JVMState* jvms) {

    Compile *C = Compile::current();

    C->log_inline_id(this);

    // Record that this call site should be revisited once the main

    // parse is finished.

    if (!is_mh_late_inline()) {

      C->add_late_inline(this);

    }

    // Emit the CallStaticJava and request separate projections so

    // that the late inlining logic can distinguish between fall

    // through and exceptional uses of the memory and io projections

    // as is done for allocations and macro expansion.

    return DirectCallGenerator::generate(jvms);

  }

  virtual void print_inlining_late(const char* msg) {

    CallNode* call = call_node();

    Compile* C = Compile::current();

    C->print_inlining_assert_ready();

    C->print_inlining(method(), call->jvms()->depth()-1, call->jvms()->bci(), msg);

    C->print_inlining_move_to(this);

    C->print_inlining_update_delayed(this);

  }

  virtual void set_unique_id(jlong id) {

    _unique_id = id;

  }

  virtual jlong unique_id() const {

    return _unique_id;

  }

};

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;

  }

  // check for unreachable loop

  CallProjections callprojs;

  call->extract_projections(&callprojs, true);

  if (callprojs.fallthrough_catchproj == call->in(0) ||

      callprojs.catchall_catchproj == call->in(0) ||

      callprojs.fallthrough_memproj == call->in(TypeFunc::Memory) ||

      callprojs.catchall_memproj == call->in(TypeFunc::Memory) ||

      callprojs.fallthrough_ioproj == call->in(TypeFunc::I_O) ||

      callprojs.catchall_ioproj == call->in(TypeFunc::I_O) ||

      (callprojs.resproj != NULL && call->find_edge(callprojs.resproj) != -1) ||

      (callprojs.exobj != NULL && call->find_edge(callprojs.exobj) != -1)) {

    return;

  }

  Compile* C = Compile::current();

  // Remove inlined methods from Compiler's lists.

  if (call->is_macro()) {

    C->remove_macro_node(call);

  }

  bool result_not_used = (callprojs.resproj == NULL || callprojs.resproj->outcnt() == 0);

  if (_is_pure_call && result_not_used) {

    // The call is marked as pure (no important side effects), but result isn't used.

    // It's safe to remove the call.

    GraphKit kit(call->jvms());

    kit.replace_call(call, C->top(), true);

  } else {

    // 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 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(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));

    }

    C->print_inlining_assert_ready();

    C->print_inlining_move_to(this);

    C->log_late_inline(this);

    // 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;

    }

    // Setup default node notes to be picked up by the inlining

    Node_Notes* old_nn = C->node_notes_at(call->_idx);

    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 inlining 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();

    }

    C->set_has_loops(C->has_loops() || _inline_cg->method()->has_loops());

    C->env()->notice_inlined_method(_inline_cg->method());

    C->set_inlining_progress(true);

    C->set_do_cleanup(kit.stopped()); // path is dead; needs cleanup

    kit.replace_call(call, result, true);

  }

}

CallGenerator* CallGenerator::for_late_inline(ciMethod* method, CallGenerator* inline_cg) {

  return new LateInlineCallGenerator(method, inline_cg);

}

class LateInlineMHCallGenerator : public LateInlineCallGenerator {

  ciMethod* _caller;

  int _attempt;

  bool _input_not_const;

  virtual bool do_late_inline_check(JVMState* jvms);

  virtual bool already_attempted() const { return _attempt > 0; }

 public:

  LateInlineMHCallGenerator(ciMethod* caller, ciMethod* callee, bool input_not_const) :

    LateInlineCallGenerator(callee, NULL), _caller(caller), _attempt(0), _input_not_const(input_not_const) {}

  virtual bool is_mh_late_inline() const { return true; }

  virtual JVMState* generate(JVMState* jvms) {

    JVMState* new_jvms = LateInlineCallGenerator::generate(jvms);

    Compile* C = Compile::current();

    if (_input_not_const) {

      // inlining won't be possible so no need to enqueue right now.

      call_node()->set_generator(this);

    } else {

      C->add_late_inline(this);

    }

    return new_jvms;

  }

};