/*

 * Copyright (c) 2010, 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 "compiler/compileBroker.hpp"

#include "compiler/compilerOracle.hpp"

#include "compiler/tieredThresholdPolicy.hpp"

#include "memory/resourceArea.hpp"

#include "runtime/arguments.hpp"

#include "runtime/frame.inline.hpp"

#include "runtime/handles.inline.hpp"

#include "runtime/safepoint.hpp"

#include "runtime/safepointVerifiers.hpp"

#include "code/scopeDesc.hpp"

#include "oops/method.inline.hpp"

#if INCLUDE_JVMCI

#include "jvmci/jvmci.hpp"

#endif

#ifdef TIERED

#include "c1/c1_Compiler.hpp"

#include "opto/c2compiler.hpp"

  double threshold_scaling;

  if (CompilerOracle::has_option_value(method, "CompileThresholdScaling", threshold_scaling)) {

    scale *= threshold_scaling;

  }

  switch(cur_level) {

  case CompLevel_aot:

    if (CompilationModeFlag::disable_intermediate()) {

      return (i >= Tier0AOTInvocationThreshold * scale) ||

             (i >= Tier0AOTMinInvocationThreshold * scale && i + b >= Tier0AOTCompileThreshold * scale);

    } else {

      return (i >= Tier3AOTInvocationThreshold * scale) ||

             (i >= Tier3AOTMinInvocationThreshold * scale && i + b >= Tier3AOTCompileThreshold * scale);

    }

  case CompLevel_none:

    if (CompilationModeFlag::disable_intermediate()) {

      return (i >= Tier40InvocationThreshold * scale) ||

             (i >= Tier40MinInvocationThreshold * scale && i + b >= Tier40CompileThreshold * scale);

    }

    // Fall through

  case CompLevel_limited_profile:

    return (i >= Tier3InvocationThreshold * scale) ||

           (i >= Tier3MinInvocationThreshold * scale && i + b >= Tier3CompileThreshold * scale);

  case CompLevel_full_profile:

   return (i >= Tier4InvocationThreshold * scale) ||

          (i >= Tier4MinInvocationThreshold * scale && i + b >= Tier4CompileThreshold * scale);

  default:

   return true;

  }

}

  double threshold_scaling;

  if (CompilerOracle::has_option_value(method, "CompileThresholdScaling", threshold_scaling)) {

    scale *= threshold_scaling;

  }

  switch(cur_level) {

  case CompLevel_aot:

    if (CompilationModeFlag::disable_intermediate()) {

      return b >= Tier0AOTBackEdgeThreshold * scale;

    } else {

      return b >= Tier3AOTBackEdgeThreshold * scale;

    }

  case CompLevel_none:

    if (CompilationModeFlag::disable_intermediate()) {

      return b >= Tier40BackEdgeThreshold * scale;

    }

    // Fall through

  case CompLevel_limited_profile:

    return b >= Tier3BackEdgeThreshold * scale;

  case CompLevel_full_profile:

    return b >= Tier4BackEdgeThreshold * scale;

  default:

    return true;

  }

}

// Simple methods are as good being compiled with C1 as C2.

// Determine if a given method is such a case.

bool TieredThresholdPolicy::is_trivial(Method* method) {

  if (method->is_accessor() ||

      method->is_constant_getter()) {

    return true;

  }

  return false;

}

  if (CompilationModeFlag::quick_internal()) {

#if INCLUDE_JVMCI

    if (UseJVMCICompiler) {

      AbstractCompiler* comp = CompileBroker::compiler(CompLevel_full_optimization);

      if (comp != NULL && comp->is_jvmci() && ((JVMCICompiler*) comp)->force_comp_at_level_simple(method)) {

        return true;

      }

    }

#endif

  }

  return false;

}

CompLevel TieredThresholdPolicy::comp_level(Method* method) {

  CompiledMethod *nm = method->code();

  if (nm != NULL && nm->is_in_use()) {

    return (CompLevel)nm->comp_level();

  }

  return CompLevel_none;

}

  int mdo_invocations = 0, mdo_backedges = 0;

  int mdo_invocations_start = 0, mdo_backedges_start = 0;

  if (mdh != NULL) {

    mdo_invocations = mdh->invocation_count();

    mdo_backedges = mdh->backedge_count();

    mdo_invocations_start = mdh->invocation_count_start();

    mdo_backedges_start = mdh->backedge_count_start();

  }

  tty->print(" %stotal=%d,%d %smdo=%d(%d),%d(%d)", prefix,

      invocation_count, backedge_count, prefix,

      mdo_invocations, mdo_invocations_start,

      mdo_backedges, mdo_backedges_start);

  tty->print(" %smax levels=%d,%d", prefix,

}

// Print an event.

                                        int bci, CompLevel level) {

  ttyLocker tty_lock;

  tty->print("%lf: [", os::elapsedTime());

  switch(type) {

  case CALL:

    tty->print("call");

    break;

  case LOOP:

    tty->print("loop");

    break;

  case COMPILE:

    tty->print("compile");

    break;

  case REMOVE_FROM_QUEUE:

    tty->print("remove-from-queue");

    break;

  case UPDATE_IN_QUEUE:

    tty->print("update-in-queue");

    break;

  case REPROFILE:

    tty->print("reprofile");

    break;

  case MAKE_NOT_ENTRANT:

    tty->print("make-not-entrant");

    break;

  default:

    tty->print("unknown");

  }

  tty->print(" level=%d ", level);

  ResourceMark rm;

  tty->print("[%s", method_name);

  if (inlinee_event) {

    tty->print(" [%s]] ", inlinee_name);

  }

  else tty->print("] ");

  tty->print("@%d queues=%d,%d", bci, CompileBroker::queue_size(CompLevel_full_profile),

                                      CompileBroker::queue_size(CompLevel_full_optimization));

  tty->print(" rate=");

  tty->print(" k=%.2lf,%.2lf", threshold_scale(CompLevel_full_profile, Tier3LoadFeedback),

                               threshold_scale(CompLevel_full_optimization, Tier4LoadFeedback));

  if (type != COMPILE) {

    if (inlinee_event) {

    }

    tty->print(" compilable=");

    bool need_comma = false;

      tty->print("c1");

      need_comma = true;

    }

      if (need_comma) tty->print(",");

      tty->print("c1-osr");

      need_comma = true;

    }

      if (need_comma) tty->print(",");

      tty->print("c2");

      need_comma = true;

    }

      if (need_comma) tty->print(",");

      tty->print("c2-osr");

    }

    tty->print(" status=");

      tty->print("in-queue");

    } else tty->print("idle");

  }

  tty->print_cr("]");

}

void TieredThresholdPolicy::initialize() {

  int count = CICompilerCount;

  bool c1_only = TieredStopAtLevel < CompLevel_full_optimization || CompilationModeFlag::quick_only();

  bool c2_only = CompilationModeFlag::high_only();

#ifdef _LP64

  // Turn on ergonomic compiler count selection

  if (FLAG_IS_DEFAULT(CICompilerCountPerCPU) && FLAG_IS_DEFAULT(CICompilerCount)) {

    FLAG_SET_DEFAULT(CICompilerCountPerCPU, true);

  }

  if (CICompilerCountPerCPU) {

    // Simple log n seems to grow too slowly for tiered, try something faster: log n * log log n

    int log_cpu = log2_int(os::active_processor_count());

    int loglog_cpu = log2_int(MAX2(log_cpu, 1));

    count = MAX2(log_cpu * loglog_cpu * 3 / 2, 2);

    // Make sure there is enough space in the code cache to hold all the compiler buffers

    size_t c1_size = Compiler::code_buffer_size();

    size_t c2_size = C2Compiler::initial_code_buffer_size();

    size_t buffer_size = c1_only ? c1_size : (c1_size/3 + 2*c2_size/3);

    int max_count = (ReservedCodeCacheSize - (CodeCacheMinimumUseSpace DEBUG_ONLY(* 3))) / (int)buffer_size;

    if (count > max_count) {

      // Lower the compiler count such that all buffers fit into the code cache

      count = MAX2(max_count, c1_only ? 1 : 2);

    }

    FLAG_SET_ERGO(CICompilerCount, count);

  }

#else

  // On 32-bit systems, the number of compiler threads is limited to 3.

  // On these systems, the virtual address space available to the JVM

  // is usually limited to 2-4 GB (the exact value depends on the platform).

  // As the compilers (especially C2) can consume a large amount of

  // memory, scaling the number of compiler threads with the number of

  // available cores can result in the exhaustion of the address space

  /// available to the VM and thus cause the VM to crash.

  if (FLAG_IS_DEFAULT(CICompilerCount)) {

    count = 3;

    FLAG_SET_ERGO(CICompilerCount, count);

  }

#endif

  if (c1_only) {

    // No C2 compiler thread required

    set_c1_count(count);

  } else if (c2_only) {

    set_c2_count(count);

  } else {

    set_c1_count(MAX2(count / 3, 1));

    set_c2_count(MAX2(count - c1_count(), 1));

  }

  assert(count == c1_count() + c2_count(), "inconsistent compiler thread count");

  // Some inlining tuning

#ifdef X86

  if (FLAG_IS_DEFAULT(InlineSmallCode)) {

    FLAG_SET_DEFAULT(InlineSmallCode, 2000);

  }

#endif

#if defined SPARC || defined AARCH64

  if (FLAG_IS_DEFAULT(InlineSmallCode)) {

    FLAG_SET_DEFAULT(InlineSmallCode, 2500);

  }

#endif

  set_increase_threshold_at_ratio();

  set_start_time(os::javaTimeMillis());

}

void TieredThresholdPolicy::set_carry_if_necessary(InvocationCounter *counter) {

  if (!counter->carry() && counter->count() > InvocationCounter::count_limit / 2) {

    counter->set_carry_flag();

  }

}

// Set carry flags on the counters if necessary

void TieredThresholdPolicy::handle_counter_overflow(Method* method) {

  MethodCounters *mcs = method->method_counters();

  if (mcs != NULL) {

    set_carry_if_necessary(mcs->invocation_counter());

    set_carry_if_necessary(mcs->backedge_counter());

  }

  MethodData* mdo = method->method_data();

  if (mdo != NULL) {

    set_carry_if_necessary(mdo->invocation_counter());

    set_carry_if_necessary(mdo->backedge_counter());

  }

}

// Called with the queue locked and with at least one element

CompileTask* TieredThresholdPolicy::select_task(CompileQueue* compile_queue) {

  CompileTask *max_blocking_task = NULL;

  CompileTask *max_task = NULL;

  Method* max_method = NULL;

  jlong t = os::javaTimeMillis();

  // Iterate through the queue and find a method with a maximum rate.

  for (CompileTask* task = compile_queue->first(); task != NULL;) {

    CompileTask* next_task = task->next();

    Method* method = task->method();

    // If a method was unloaded or has been stale for some time, remove it from the queue.

    // Blocking tasks and tasks submitted from whitebox API don't become stale

    if (task->is_unloaded() || (task->can_become_stale() && is_stale(t, TieredCompileTaskTimeout, method) && !is_old(method))) {

      if (!task->is_unloaded()) {

        if (PrintTieredEvents) {

          print_event(REMOVE_FROM_QUEUE, method, method, task->osr_bci(), (CompLevel) task->comp_level());

        }

        method->clear_queued_for_compilation();

      }

      compile_queue->remove_and_mark_stale(task);

      task = next_task;

      continue;

    }

    update_rate(t, method);

    if (max_task == NULL || compare_methods(method, max_method)) {

      // Select a method with the highest rate

      max_task = task;

      max_method = method;

    }

    if (task->is_blocking()) {

      if (max_blocking_task == NULL || compare_methods(method, max_blocking_task->method())) {

        max_blocking_task = task;

      }

    }

    task = next_task;

  }

  if (max_blocking_task != NULL) {

    // In blocking compilation mode, the CompileBroker will make

    // compilations submitted by a JVMCI compiler thread non-blocking. These

    // compilations should be scheduled after all blocking compilations

    // to service non-compiler related compilations sooner and reduce the

    // chance of such compilations timing out.

    max_task = max_blocking_task;

    max_method = max_task->method();

  }

  if (max_task != NULL && max_task->comp_level() == CompLevel_full_profile &&

      TieredStopAtLevel > CompLevel_full_profile &&

    max_task->set_comp_level(CompLevel_limited_profile);

      if (PrintTieredEvents) {

        print_event(REMOVE_FROM_QUEUE, max_method, max_method, max_task->osr_bci(), (CompLevel)max_task->comp_level());

      }

      compile_queue->remove_and_mark_stale(max_task);

      max_method->clear_queued_for_compilation();

      return NULL;

    }

    if (PrintTieredEvents) {

      print_event(UPDATE_IN_QUEUE, max_method, max_method, max_task->osr_bci(), (CompLevel)max_task->comp_level());

    }

  }

  return max_task;

}

void TieredThresholdPolicy::reprofile(ScopeDesc* trap_scope, bool is_osr) {

  for (ScopeDesc* sd = trap_scope;; sd = sd->sender()) {

    if (PrintTieredEvents) {

    }

    MethodData* mdo = sd->method()->method_data();

    if (mdo != NULL) {

      mdo->reset_start_counters();

    }

    if (sd->is_top()) break;

  }

}

nmethod* TieredThresholdPolicy::event(const methodHandle& method, const methodHandle& inlinee,

                                      int branch_bci, int bci, CompLevel comp_level, CompiledMethod* nm, JavaThread* thread) {

  if (comp_level == CompLevel_none &&

      JvmtiExport::can_post_interpreter_events() &&

      thread->is_interp_only_mode()) {

    return NULL;

  }

  if (ReplayCompiles) {

    // Don't trigger other compiles in testing mode

    return NULL;

  }

  handle_counter_overflow(method());

  if (method() != inlinee()) {

    handle_counter_overflow(inlinee());

  }

  if (PrintTieredEvents) {

  }

  if (bci == InvocationEntryBci) {

    method_invocation_event(method, inlinee, comp_level, nm, thread);

  } else {

    // method == inlinee if the event originated in the main method

    method_back_branch_event(method, inlinee, bci, comp_level, nm, thread);

    // Check if event led to a higher level OSR compilation

    CompLevel expected_comp_level = comp_level;

    if (!CompilationModeFlag::disable_intermediate() && inlinee->is_not_osr_compilable(expected_comp_level)) {

      // It's not possble to reach the expected level so fall back to simple.

      expected_comp_level = CompLevel_simple;

    }

    nmethod* osr_nm = inlinee->lookup_osr_nmethod_for(bci, expected_comp_level, false);

    assert(osr_nm == NULL || osr_nm->comp_level() >= expected_comp_level, "lookup_osr_nmethod_for is broken");

    if (osr_nm != NULL) {

      // Perform OSR with new nmethod

      return osr_nm;

    }

  }

  return NULL;

}

// Check if the method can be compiled, change level if necessary

void TieredThresholdPolicy::compile(const methodHandle& mh, int bci, CompLevel level, JavaThread* thread) {

  assert(level <= TieredStopAtLevel, "Invalid compilation level");

  if (CompilationModeFlag::quick_only()) {

    assert(level <= CompLevel_simple, "Invalid compilation level");

  } else if (CompilationModeFlag::disable_intermediate()) {

    assert(level != CompLevel_full_profile && level != CompLevel_limited_profile, "C1 profiling levels shouldn't be used with intermediate levels disabled");

  }

  if (level == CompLevel_none) {

    if (mh->has_compiled_code()) {

      // Happens when we switch from AOT to interpreter to profile.

      MutexLocker ml(Compile_lock);

      NoSafepointVerifier nsv;

      if (mh->has_compiled_code()) {

        mh->code()->make_not_used();

      }

      // Deoptimize immediately (we don't have to wait for a compile).

      RegisterMap map(thread, false);

      frame fr = thread->last_frame().sender(&map);

      Deoptimization::deoptimize_frame(thread, fr.id());

    }

    return;

  }

  if (level == CompLevel_aot) {

    if (mh->has_aot_code()) {

      if (PrintTieredEvents) {

      }

      MutexLocker ml(Compile_lock);

      NoSafepointVerifier nsv;

      if (mh->has_aot_code() && mh->code() != mh->aot_code()) {

        mh->aot_code()->make_entrant();

        if (mh->has_compiled_code()) {