/*

 * Copyright (c) 1998, 2011, 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/ciCPCache.hpp"

#include "ci/ciCallSite.hpp"

#include "ci/ciMethodHandle.hpp"

#include "classfile/vmSymbols.hpp"

#include "compiler/compileBroker.hpp"

#include "compiler/compileLog.hpp"

#include "interpreter/linkResolver.hpp"

#include "opto/addnode.hpp"

#include "opto/callGenerator.hpp"

#include "opto/cfgnode.hpp"

#include "opto/mulnode.hpp"

#include "opto/parse.hpp"

#include "opto/rootnode.hpp"

#include "opto/runtime.hpp"

#include "opto/subnode.hpp"

#include "prims/nativeLookup.hpp"

#include "runtime/sharedRuntime.hpp"

#ifndef PRODUCT

void trace_type_profile(ciMethod *method, int depth, int bci, ciMethod *prof_method, ciKlass *prof_klass, int site_count, int receiver_count) {

  if (TraceTypeProfile || PrintInlining || PrintOptoInlining) {

    if (!PrintInlining) {

      if (!PrintOpto && !PrintCompilation) {

        method->print_short_name();

        tty->cr();

      }

      CompileTask::print_inlining(prof_method, depth, bci);

    }

    CompileTask::print_inline_indent(depth);

    tty->print(" \\-> TypeProfile (%d/%d counts) = ", receiver_count, site_count);

    prof_klass->name()->print_symbol();

    tty->cr();

  }

}

#endif

CallGenerator* Compile::call_generator(ciMethod* call_method, int vtable_index, bool call_is_virtual,

                                       JVMState* jvms, bool allow_inline,

                                       float prof_factor) {

  ciMethod*       caller   = jvms->method();

  int             bci      = jvms->bci();

  Bytecodes::Code bytecode = caller->java_code_at_bci(bci);

  guarantee(call_method != NULL, "failed method resolution");

  // Dtrace currently doesn't work unless all calls are vanilla

  if (env()->dtrace_method_probes()) {

    allow_inline = false;

  }

  // Note: When we get profiling during stage-1 compiles, we want to pull

  // from more specific profile data which pertains to this inlining.

  // Right now, ignore the information in jvms->caller(), and do method[bci].

  ciCallProfile profile = caller->call_profile_at_bci(bci);

  // See how many times this site has been invoked.

  int site_count = profile.count();

  int receiver_count = -1;

  if (call_is_virtual && UseTypeProfile && profile.has_receiver(0)) {

    // Receivers in the profile structure are ordered by call counts

    // so that the most called (major) receiver is profile.receiver(0).

    receiver_count = profile.receiver_count(0);

  }

  CompileLog* log = this->log();

  if (log != NULL) {

    int rid = (receiver_count >= 0)? log->identify(profile.receiver(0)): -1;

    int r2id = (rid != -1 && profile.has_receiver(1))? log->identify(profile.receiver(1)):-1;

    log->begin_elem("call method='%d' count='%d' prof_factor='%g'",

                    log->identify(call_method), site_count, prof_factor);

    if (call_is_virtual)  log->print(" virtual='1'");

    if (allow_inline)     log->print(" inline='1'");

    if (receiver_count >= 0) {

      log->print(" receiver='%d' receiver_count='%d'", rid, receiver_count);

      if (profile.has_receiver(1)) {

        log->print(" receiver2='%d' receiver2_count='%d'", r2id, profile.receiver_count(1));

      }

    }

    log->end_elem();

  }

  // Special case the handling of certain common, profitable library

  // methods.  If these methods are replaced with specialized code,

  // then we return it as the inlined version of the call.

  // We do this before the strict f.p. check below because the

  // intrinsics handle strict f.p. correctly.

  if (allow_inline) {

    if (cg != NULL)  return cg;

  }

  // Do method handle calls.

  // NOTE: This must happen before normal inlining logic below since

  // MethodHandle.invoke* are native methods which obviously don't

  // have bytecodes and so normal inlining fails.

  if (call_method->is_method_handle_invoke()) {

    if (bytecode != Bytecodes::_invokedynamic) {

      GraphKit kit(jvms);

    }

    else {

    }

  }

  // Do not inline strict fp into non-strict code, or the reverse

    allow_inline = false;

  }

  // Attempt to inline...

  if (allow_inline) {

    // The profile data is only partly attributable to this caller,

    // scale back the call site information.

    float past_uses = jvms->method()->scale_count(site_count, prof_factor);

    // This is the number of times we expect the call code to be used.

    float expected_uses = past_uses;

    // Try inlining a bytecoded method:

    if (!call_is_virtual) {

      InlineTree* ilt;

      if (UseOldInlining) {

        ilt = InlineTree::find_subtree_from_root(this->ilt(), jvms->caller(), jvms->method());

      } else {

        // Make a disembodied, stateless ILT.

        // TO DO:  When UseOldInlining is removed, copy the ILT code elsewhere.

        float site_invoke_ratio = prof_factor;

        // Note:  ilt is for the root of this parse, not the present call site.

        ilt = new InlineTree(this, jvms->method(), jvms->caller(), site_invoke_ratio, MaxInlineLevel);

      }

      WarmCallInfo scratch_ci;

      if (!UseOldInlining)

        scratch_ci.init(jvms, call_method, profile, prof_factor);

      WarmCallInfo* ci = ilt->ok_to_inline(call_method, jvms, profile, &scratch_ci);

      assert(ci != &scratch_ci, "do not let this pointer escape");

      bool allow_inline   = (ci != NULL && !ci->is_cold());

      bool require_inline = (allow_inline && ci->is_hot());

      if (allow_inline) {

        CallGenerator* cg = CallGenerator::for_inline(call_method, expected_uses);

        if (require_inline && cg != NULL && should_delay_inlining(call_method, jvms)) {

          // Delay the inlining of this method to give us the

          // opportunity to perform some high level optimizations

          // first.

          return CallGenerator::for_late_inline(call_method, cg);

        }

        if (cg == NULL) {

          // Fall through.

        } else if (require_inline || !InlineWarmCalls) {

          return cg;

        } else {

          CallGenerator* cold_cg = call_generator(call_method, vtable_index, call_is_virtual, jvms, false, prof_factor);

          return CallGenerator::for_warm_call(ci, cold_cg, cg);

        }

      }

    }

    // Try using the type profile.

    if (call_is_virtual && site_count > 0 && receiver_count > 0) {

      // The major receiver's count >= TypeProfileMajorReceiverPercent of site_count.

      bool have_major_receiver = (100.*profile.receiver_prob(0) >= (float)TypeProfileMajorReceiverPercent);

      ciMethod* receiver_method = NULL;

      if (have_major_receiver || profile.morphism() == 1 ||

          (profile.morphism() == 2 && UseBimorphicInlining)) {

        // receiver_method = profile.method();

        // Profiles do not suggest methods now.  Look it up in the major receiver.

        receiver_method = call_method->resolve_invoke(jvms->method()->holder(),

                                                      profile.receiver(0));

      }

      if (receiver_method != NULL) {

        // The single majority receiver sufficiently outweighs the minority.

        CallGenerator* hit_cg = this->call_generator(receiver_method,

              vtable_index, !call_is_virtual, jvms, allow_inline, prof_factor);

        if (hit_cg != NULL) {

          // Look up second receiver.

          CallGenerator* next_hit_cg = NULL;

          ciMethod* next_receiver_method = NULL;

          if (profile.morphism() == 2 && UseBimorphicInlining) {

            next_receiver_method = call_method->resolve_invoke(jvms->method()->holder(),

                                                               profile.receiver(1));

            if (next_receiver_method != NULL) {

              next_hit_cg = this->call_generator(next_receiver_method,

                                  vtable_index, !call_is_virtual, jvms,

                                  allow_inline, prof_factor);

              if (next_hit_cg != NULL && !next_hit_cg->is_inline() &&

                  have_major_receiver && UseOnlyInlinedBimorphic) {

                  // Skip if we can't inline second receiver's method

                  next_hit_cg = NULL;

              }

            }

          }

          CallGenerator* miss_cg;

          Deoptimization::DeoptReason reason = (profile.morphism() == 2) ?

                                    Deoptimization::Reason_bimorphic :

                                    Deoptimization::Reason_class_check;

          if (( profile.morphism() == 1 ||

               (profile.morphism() == 2 && next_hit_cg != NULL) ) &&

              !too_many_traps(jvms->method(), jvms->bci(), reason)

             ) {

            // Generate uncommon trap for class check failure path

            // in case of monomorphic or bimorphic virtual call site.

            miss_cg = CallGenerator::for_uncommon_trap(call_method, reason,

                        Deoptimization::Action_maybe_recompile);

          } else {

            // Generate virtual call for class check failure path

            // in case of polymorphic virtual call site.

            miss_cg = CallGenerator::for_virtual_call(call_method, vtable_index);

          }

          if (miss_cg != NULL) {

            if (next_hit_cg != NULL) {

              NOT_PRODUCT(trace_type_profile(jvms->method(), jvms->depth() - 1, jvms->bci(), next_receiver_method, profile.receiver(1), site_count, profile.receiver_count(1)));

              // We don't need to record dependency on a receiver here and below.

              // Whenever we inline, the dependency is added by Parse::Parse().

              miss_cg = CallGenerator::for_predicted_call(profile.receiver(1), miss_cg, next_hit_cg, PROB_MAX);

            }

            if (miss_cg != NULL) {

              NOT_PRODUCT(trace_type_profile(jvms->method(), jvms->depth() - 1, jvms->bci(), receiver_method, profile.receiver(0), site_count, receiver_count));

              if (cg != NULL)  return cg;

            }

          }

        }

      }

    }

  }

  // There was no special inlining tactic, or it bailed out.

  // Use a more generic tactic, like a simple call.

  if (call_is_virtual) {

    return CallGenerator::for_virtual_call(call_method, vtable_index);

  } else {

    // Class Hierarchy Analysis or Type Profile reveals a unique target,

    // or it is a static or special call.

    return CallGenerator::for_direct_call(call_method, should_delay_inlining(call_method, jvms));

  }

}

// Return true for methods that shouldn't be inlined early so that

// they are easier to analyze and optimize as intrinsics.

bool Compile::should_delay_inlining(ciMethod* call_method, JVMState* jvms) {

  if (has_stringbuilder()) {

    if ((call_method->holder() == C->env()->StringBuilder_klass() ||

         call_method->holder() == C->env()->StringBuffer_klass()) &&

        (jvms->method()->holder() == C->env()->StringBuilder_klass() ||

         jvms->method()->holder() == C->env()->StringBuffer_klass())) {

      // Delay SB calls only when called from non-SB code

      return false;

    }

    switch (call_method->intrinsic_id()) {

      case vmIntrinsics::_StringBuilder_void:

      case vmIntrinsics::_StringBuilder_int:

      case vmIntrinsics::_StringBuilder_String:

      case vmIntrinsics::_StringBuilder_append_char:

      case vmIntrinsics::_StringBuilder_append_int:

      case vmIntrinsics::_StringBuilder_append_String:

      case vmIntrinsics::_StringBuilder_toString:

      case vmIntrinsics::_StringBuffer_void:

      case vmIntrinsics::_StringBuffer_int:

      case vmIntrinsics::_StringBuffer_String:

      case vmIntrinsics::_StringBuffer_append_char:

      case vmIntrinsics::_StringBuffer_append_int:

      case vmIntrinsics::_StringBuffer_append_String:

      case vmIntrinsics::_StringBuffer_toString:

      case vmIntrinsics::_Integer_toString:

        return true;

      case vmIntrinsics::_String_String:

        {

          Node* receiver = jvms->map()->in(jvms->argoff() + 1);

          if (receiver->is_Proj() && receiver->in(0)->is_CallStaticJava()) {

            CallStaticJavaNode* csj = receiver->in(0)->as_CallStaticJava();

            ciMethod* m = csj->method();

            if (m != NULL &&

                (m->intrinsic_id() == vmIntrinsics::_StringBuffer_toString ||

                 m->intrinsic_id() == vmIntrinsics::_StringBuilder_toString))

              // Delay String.<init>(new SB())

              return true;

          }

          return false;

        }

      default:

        return false;

    }

  }

  return false;

}

// uncommon-trap call-sites where callee is unloaded, uninitialized or will not link

bool Parse::can_not_compile_call_site(ciMethod *dest_method, ciInstanceKlass* klass) {

  // Additional inputs to consider...

  // bc      = bc()

  // caller  = method()

  // iter().get_method_holder_index()

  assert( dest_method->is_loaded(), "ciTypeFlow should not let us get here" );

  // Interface classes can be loaded & linked and never get around to

  // being initialized.  Uncommon-trap for not-initialized static or

  // v-calls.  Let interface calls happen.

  ciInstanceKlass* holder_klass = dest_method->holder();

  if (!holder_klass->is_being_initialized() &&

      !holder_klass->is_initialized() &&

      !holder_klass->is_interface()) {

    uncommon_trap(Deoptimization::Reason_uninitialized,

                  Deoptimization::Action_reinterpret,

                  holder_klass);

    return true;

  }

  assert(dest_method->will_link(method()->holder(), klass, bc()), "dest_method: typeflow responsibility");

  return false;

}

//------------------------------do_call----------------------------------------

// Handle your basic call.  Inline if we can & want to, else just setup call.

void Parse::do_call() {

  // It's likely we are going to add debug info soon.

  // Also, if we inline a guy who eventually needs debug info for this JVMS,

  // our contribution to it is cleaned up right here.

  kill_dead_locals();

  // Set frequently used booleans

  bool is_virtual = bc() == Bytecodes::_invokevirtual;

  bool is_virtual_or_interface = is_virtual || bc() == Bytecodes::_invokeinterface;

  bool has_receiver = is_virtual_or_interface || bc() == Bytecodes::_invokespecial;

  bool is_invokedynamic = bc() == Bytecodes::_invokedynamic;

  // Find target being called

  bool             will_link;

  ciMethod*        dest_method   = iter().get_method(will_link);

  ciInstanceKlass* holder_klass  = dest_method->holder();

  ciKlass* holder = iter().get_declared_method_holder();

  ciInstanceKlass* klass = ciEnv::get_instance_klass_for_declared_method_holder(holder);

  int nargs = dest_method->arg_size();

  if (is_invokedynamic)  nargs -= 1;

  // uncommon-trap when callee is unloaded, uninitialized or will not link

  // bailout when too many arguments for register representation

  if (!will_link || can_not_compile_call_site(dest_method, klass)) {

#ifndef PRODUCT

    if (PrintOpto && (Verbose || WizardMode)) {

      method()->print_name(); tty->print_cr(" can not compile call at bci %d to:", bci());

      dest_method->print_name(); tty->cr();

    }

#endif

    return;

  }

  assert(holder_klass->is_loaded(), "");

  assert((dest_method->is_static() || is_invokedynamic) == !has_receiver , "must match bc");

  // Note: this takes into account invokeinterface of methods declared in java/lang/Object,

  // which should be invokevirtuals but according to the VM spec may be invokeinterfaces

  assert(holder_klass->is_interface() || holder_klass->super() == NULL || (bc() != Bytecodes::_invokeinterface), "must match bc");

  // Note:  In the absence of miranda methods, an abstract class K can perform

  // an invokevirtual directly on an interface method I.m if K implements I.

  // ---------------------

  // Does Class Hierarchy Analysis reveal only a single target of a v-call?

  // Then we may inline or make a static call, but become dependent on there being only 1 target.

  // Does the call-site type profile reveal only one receiver?

  // Then we may introduce a run-time check and inline on the path where it succeeds.

  // The other path may uncommon_trap, check for another receiver, or do a v-call.

  // Choose call strategy.

  bool call_is_virtual = is_virtual_or_interface;

  int vtable_index = methodOopDesc::invalid_vtable_index;

  ciMethod* call_method = dest_method;

  // Try to get the most accurate receiver type

  if (is_virtual_or_interface) {

    Node*             receiver_node = stack(sp() - nargs);

    const TypeOopPtr* receiver_type = _gvn.type(receiver_node)->isa_oopptr();

    ciMethod* optimized_virtual_method = optimize_inlining(method(), bci(), klass, dest_method, receiver_type);

    // Have the call been sufficiently improved such that it is no longer a virtual?

    if (optimized_virtual_method != NULL) {

      call_method     = optimized_virtual_method;

      call_is_virtual = false;

    } else if (!UseInlineCaches && is_virtual && call_method->is_loaded()) {

      // We can make a vtable call at this site

      vtable_index = call_method->resolve_vtable_index(method()->holder(), klass);

    }

  }

  // Note:  It's OK to try to inline a virtual call.

  // The call generator will not attempt to inline a polymorphic call

  // unless it knows how to optimize the receiver dispatch.

  bool try_inline = (C->do_inlining() || InlineAccessors);

  // ---------------------

  inc_sp(- nargs);              // Temporarily pop args for JVM state of call

  JVMState* jvms = sync_jvms();

  // ---------------------

  // Decide call tactic.

  // This call checks with CHA, the interpreter profile, intrinsics table, etc.

  // It decides whether inlining is desirable or not.

  CallGenerator* cg = C->call_generator(call_method, vtable_index, call_is_virtual, jvms, try_inline, prof_factor());

  // ---------------------

  // Round double arguments before call

  round_double_arguments(dest_method);

#ifndef PRODUCT

  // bump global counters for calls

  count_compiled_calls(false/*at_method_entry*/, cg->is_inline());

  // Record first part of parsing work for this call

  parse_histogram()->record_change();

#endif // not PRODUCT

  assert(jvms == this->jvms(), "still operating on the right JVMS");

  assert(jvms_in_sync(),       "jvms must carry full info into CG");

  // save across call, for a subsequent cast_not_null.

  Node* receiver = has_receiver ? argument(0) : NULL;

  // Bump method data counters (We profile *before* the call is made

  // because exceptions don't return to the call site.)

  profile_call(receiver);

  JVMState* new_jvms;

  if ((new_jvms = cg->generate(jvms)) == NULL) {

    // When inlining attempt fails (e.g., too many arguments),

    // it may contaminate the current compile state, making it

    // impossible to pull back and try again.  Once we call

    // cg->generate(), we are committed.  If it fails, the whole

    // compilation task is compromised.

    if (failing())  return;

#ifndef PRODUCT

    if (PrintOpto || PrintOptoInlining || PrintInlining) {

      // Only one fall-back, so if an intrinsic fails, ignore any bytecodes.

      if (cg->is_intrinsic() && call_method->code_size() > 0) {

        tty->print("Bailed out of intrinsic, will not inline: ");

        call_method->print_name(); tty->cr();

      }

    }

#endif

    // This can happen if a library intrinsic is available, but refuses

    // the call site, perhaps because it did not match a pattern the

    // intrinsic was expecting to optimize.  The fallback position is

    // to call out-of-line.

    try_inline = false;  // Inline tactic bailed out.

    cg = C->call_generator(call_method, vtable_index, call_is_virtual, jvms, try_inline, prof_factor());

    if ((new_jvms = cg->generate(jvms)) == NULL) {

      guarantee(failing(), "call failed to generate:  calls should work");

      return;

    }

  }

  if (cg->is_inline()) {

    // Accumulate has_loops estimate

    C->set_has_loops(C->has_loops() || call_method->has_loops());

    C->env()->notice_inlined_method(call_method);

  }

  // Reset parser state from [new_]jvms, which now carries results of the call.

  // Return value (if any) is already pushed on the stack by the cg.

  add_exception_states_from(new_jvms);

  if (new_jvms->map()->control() == top()) {

    stop_and_kill_map();

  } else {

    assert(new_jvms->same_calls_as(jvms), "method/bci left unchanged");

    set_jvms(new_jvms);

  }

  if (!stopped()) {

    // This was some sort of virtual call, which did a null check for us.

    // Now we can assert receiver-not-null, on the normal return path.

    if (receiver != NULL && cg->is_virtual()) {

      Node* cast = cast_not_null(receiver);

      // %%% assert(receiver == cast, "should already have cast the receiver");

    }

    // Round double result after a call from strict to non-strict code

    round_double_result(dest_method);

    // If the return type of the method is not loaded, assert that the

    // value we got is a null.  Otherwise, we need to recompile.

    if (!dest_method->return_type()->is_loaded()) {

#ifndef PRODUCT

      if (PrintOpto && (Verbose || WizardMode)) {

        method()->print_name(); tty->print_cr(" asserting nullness of result at bci: %d", bci());

        dest_method->print_name(); tty->cr();

      }

#endif

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