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Java example source code file (parse1.cpp)

This example Java source code file (parse1.cpp) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

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Java - Java tags/keywords

block, c\-, jvmstate, node, null, osr, phinode, product, regionnode, safepointnode, typefunc\:\:parms, typerawptr\:\:bottom

The parse1.cpp Java example source code

/*
 * Copyright (c) 1997, 2013, 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/compileLog.hpp"
#include "interpreter/linkResolver.hpp"
#include "oops/method.hpp"
#include "opto/addnode.hpp"
#include "opto/idealGraphPrinter.hpp"
#include "opto/locknode.hpp"
#include "opto/memnode.hpp"
#include "opto/parse.hpp"
#include "opto/rootnode.hpp"
#include "opto/runtime.hpp"
#include "runtime/arguments.hpp"
#include "runtime/handles.inline.hpp"
#include "runtime/sharedRuntime.hpp"
#include "utilities/copy.hpp"

// Static array so we can figure out which bytecodes stop us from compiling
// the most. Some of the non-static variables are needed in bytecodeInfo.cpp
// and eventually should be encapsulated in a proper class (gri 8/18/98).

int nodes_created              = 0;
int methods_parsed             = 0;
int methods_seen               = 0;
int blocks_parsed              = 0;
int blocks_seen                = 0;

int explicit_null_checks_inserted = 0;
int explicit_null_checks_elided   = 0;
int all_null_checks_found         = 0, implicit_null_checks              = 0;
int implicit_null_throws          = 0;

int reclaim_idx  = 0;
int reclaim_in   = 0;
int reclaim_node = 0;

#ifndef PRODUCT
bool Parse::BytecodeParseHistogram::_initialized = false;
uint Parse::BytecodeParseHistogram::_bytecodes_parsed [Bytecodes::number_of_codes];
uint Parse::BytecodeParseHistogram::_nodes_constructed[Bytecodes::number_of_codes];
uint Parse::BytecodeParseHistogram::_nodes_transformed[Bytecodes::number_of_codes];
uint Parse::BytecodeParseHistogram::_new_values       [Bytecodes::number_of_codes];
#endif

//------------------------------print_statistics-------------------------------
#ifndef PRODUCT
void Parse::print_statistics() {
  tty->print_cr("--- Compiler Statistics ---");
  tty->print("Methods seen: %d  Methods parsed: %d", methods_seen, methods_parsed);
  tty->print("  Nodes created: %d", nodes_created);
  tty->cr();
  if (methods_seen != methods_parsed)
    tty->print_cr("Reasons for parse failures (NOT cumulative):");
  tty->print_cr("Blocks parsed: %d  Blocks seen: %d", blocks_parsed, blocks_seen);

  if( explicit_null_checks_inserted )
    tty->print_cr("%d original NULL checks - %d elided (%2d%%); optimizer leaves %d,", explicit_null_checks_inserted, explicit_null_checks_elided, (100*explicit_null_checks_elided)/explicit_null_checks_inserted, all_null_checks_found);
  if( all_null_checks_found )
    tty->print_cr("%d made implicit (%2d%%)", implicit_null_checks,
                  (100*implicit_null_checks)/all_null_checks_found);
  if( implicit_null_throws )
    tty->print_cr("%d implicit null exceptions at runtime",
                  implicit_null_throws);

  if( PrintParseStatistics && BytecodeParseHistogram::initialized() ) {
    BytecodeParseHistogram::print();
  }
}
#endif

//------------------------------ON STACK REPLACEMENT---------------------------

// Construct a node which can be used to get incoming state for
// on stack replacement.
Node *Parse::fetch_interpreter_state(int index,
                                     BasicType bt,
                                     Node *local_addrs,
                                     Node *local_addrs_base) {
  Node *mem = memory(Compile::AliasIdxRaw);
  Node *adr = basic_plus_adr( local_addrs_base, local_addrs, -index*wordSize );
  Node *ctl = control();

  // Very similar to LoadNode::make, except we handle un-aligned longs and
  // doubles on Sparc.  Intel can handle them just fine directly.
  Node *l;
  switch( bt ) {                // Signature is flattened
  case T_INT:     l = new (C) LoadINode( ctl, mem, adr, TypeRawPtr::BOTTOM ); break;
  case T_FLOAT:   l = new (C) LoadFNode( ctl, mem, adr, TypeRawPtr::BOTTOM ); break;
  case T_ADDRESS: l = new (C) LoadPNode( ctl, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM  ); break;
  case T_OBJECT:  l = new (C) LoadPNode( ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInstPtr::BOTTOM ); break;
  case T_LONG:
  case T_DOUBLE: {
    // Since arguments are in reverse order, the argument address 'adr'
    // refers to the back half of the long/double.  Recompute adr.
    adr = basic_plus_adr( local_addrs_base, local_addrs, -(index+1)*wordSize );
    if( Matcher::misaligned_doubles_ok ) {
      l = (bt == T_DOUBLE)
        ? (Node*)new (C) LoadDNode( ctl, mem, adr, TypeRawPtr::BOTTOM )
        : (Node*)new (C) LoadLNode( ctl, mem, adr, TypeRawPtr::BOTTOM );
    } else {
      l = (bt == T_DOUBLE)
        ? (Node*)new (C) LoadD_unalignedNode( ctl, mem, adr, TypeRawPtr::BOTTOM )
        : (Node*)new (C) LoadL_unalignedNode( ctl, mem, adr, TypeRawPtr::BOTTOM );
    }
    break;
  }
  default: ShouldNotReachHere();
  }
  return _gvn.transform(l);
}

// Helper routine to prevent the interpreter from handing
// unexpected typestate to an OSR method.
// The Node l is a value newly dug out of the interpreter frame.
// The type is the type predicted by ciTypeFlow.  Note that it is
// not a general type, but can only come from Type::get_typeflow_type.
// The safepoint is a map which will feed an uncommon trap.
Node* Parse::check_interpreter_type(Node* l, const Type* type,
                                    SafePointNode* &bad_type_exit) {

  const TypeOopPtr* tp = type->isa_oopptr();

  // TypeFlow may assert null-ness if a type appears unloaded.
  if (type == TypePtr::NULL_PTR ||
      (tp != NULL && !tp->klass()->is_loaded())) {
    // Value must be null, not a real oop.
    Node* chk = _gvn.transform( new (C) CmpPNode(l, null()) );
    Node* tst = _gvn.transform( new (C) BoolNode(chk, BoolTest::eq) );
    IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
    set_control(_gvn.transform( new (C) IfTrueNode(iff) ));
    Node* bad_type = _gvn.transform( new (C) IfFalseNode(iff) );
    bad_type_exit->control()->add_req(bad_type);
    l = null();
  }

  // Typeflow can also cut off paths from the CFG, based on
  // types which appear unloaded, or call sites which appear unlinked.
  // When paths are cut off, values at later merge points can rise
  // toward more specific classes.  Make sure these specific classes
  // are still in effect.
  if (tp != NULL && tp->klass() != C->env()->Object_klass()) {
    // TypeFlow asserted a specific object type.  Value must have that type.
    Node* bad_type_ctrl = NULL;
    l = gen_checkcast(l, makecon(TypeKlassPtr::make(tp->klass())), &bad_type_ctrl);
    bad_type_exit->control()->add_req(bad_type_ctrl);
  }

  BasicType bt_l = _gvn.type(l)->basic_type();
  BasicType bt_t = type->basic_type();
  assert(_gvn.type(l)->higher_equal(type), "must constrain OSR typestate");
  return l;
}

// Helper routine which sets up elements of the initial parser map when
// performing a parse for on stack replacement.  Add values into map.
// The only parameter contains the address of a interpreter arguments.
void Parse::load_interpreter_state(Node* osr_buf) {
  int index;
  int max_locals = jvms()->loc_size();
  int max_stack  = jvms()->stk_size();


  // Mismatch between method and jvms can occur since map briefly held
  // an OSR entry state (which takes up one RawPtr word).
  assert(max_locals == method()->max_locals(), "sanity");
  assert(max_stack  >= method()->max_stack(),  "sanity");
  assert((int)jvms()->endoff() == TypeFunc::Parms + max_locals + max_stack, "sanity");
  assert((int)jvms()->endoff() == (int)map()->req(), "sanity");

  // Find the start block.
  Block* osr_block = start_block();
  assert(osr_block->start() == osr_bci(), "sanity");

  // Set initial BCI.
  set_parse_bci(osr_block->start());

  // Set initial stack depth.
  set_sp(osr_block->start_sp());

  // Check bailouts.  We currently do not perform on stack replacement
  // of loops in catch blocks or loops which branch with a non-empty stack.
  if (sp() != 0) {
    C->record_method_not_compilable("OSR starts with non-empty stack");
    return;
  }
  // Do not OSR inside finally clauses:
  if (osr_block->has_trap_at(osr_block->start())) {
    C->record_method_not_compilable("OSR starts with an immediate trap");
    return;
  }

  // Commute monitors from interpreter frame to compiler frame.
  assert(jvms()->monitor_depth() == 0, "should be no active locks at beginning of osr");
  int mcnt = osr_block->flow()->monitor_count();
  Node *monitors_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals+mcnt*2-1)*wordSize);
  for (index = 0; index < mcnt; index++) {
    // Make a BoxLockNode for the monitor.
    Node *box = _gvn.transform(new (C) BoxLockNode(next_monitor()));


    // Displaced headers and locked objects are interleaved in the
    // temp OSR buffer.  We only copy the locked objects out here.
    // Fetch the locked object from the OSR temp buffer and copy to our fastlock node.
    Node *lock_object = fetch_interpreter_state(index*2, T_OBJECT, monitors_addr, osr_buf);
    // Try and copy the displaced header to the BoxNode
    Node *displaced_hdr = fetch_interpreter_state((index*2) + 1, T_ADDRESS, monitors_addr, osr_buf);


    store_to_memory(control(), box, displaced_hdr, T_ADDRESS, Compile::AliasIdxRaw);

    // Build a bogus FastLockNode (no code will be generated) and push the
    // monitor into our debug info.
    const FastLockNode *flock = _gvn.transform(new (C) FastLockNode( 0, lock_object, box ))->as_FastLock();
    map()->push_monitor(flock);

    // If the lock is our method synchronization lock, tuck it away in
    // _sync_lock for return and rethrow exit paths.
    if (index == 0 && method()->is_synchronized()) {
      _synch_lock = flock;
    }
  }

  // Use the raw liveness computation to make sure that unexpected
  // values don't propagate into the OSR frame.
  MethodLivenessResult live_locals = method()->liveness_at_bci(osr_bci());
  if (!live_locals.is_valid()) {
    // Degenerate or breakpointed method.
    C->record_method_not_compilable("OSR in empty or breakpointed method");
    return;
  }

  // Extract the needed locals from the interpreter frame.
  Node *locals_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals-1)*wordSize);

  // find all the locals that the interpreter thinks contain live oops
  const BitMap live_oops = method()->live_local_oops_at_bci(osr_bci());
  for (index = 0; index < max_locals; index++) {

    if (!live_locals.at(index)) {
      continue;
    }

    const Type *type = osr_block->local_type_at(index);

    if (type->isa_oopptr() != NULL) {

      // 6403625: Verify that the interpreter oopMap thinks that the oop is live
      // else we might load a stale oop if the MethodLiveness disagrees with the
      // result of the interpreter. If the interpreter says it is dead we agree
      // by making the value go to top.
      //

      if (!live_oops.at(index)) {
        if (C->log() != NULL) {
          C->log()->elem("OSR_mismatch local_index='%d'",index);
        }
        set_local(index, null());
        // and ignore it for the loads
        continue;
      }
    }

    // Filter out TOP, HALF, and BOTTOM.  (Cf. ensure_phi.)
    if (type == Type::TOP || type == Type::HALF) {
      continue;
    }
    // If the type falls to bottom, then this must be a local that
    // is mixing ints and oops or some such.  Forcing it to top
    // makes it go dead.
    if (type == Type::BOTTOM) {
      continue;
    }
    // Construct code to access the appropriate local.
    BasicType bt = type->basic_type();
    if (type == TypePtr::NULL_PTR) {
      // Ptr types are mixed together with T_ADDRESS but NULL is
      // really for T_OBJECT types so correct it.
      bt = T_OBJECT;
    }
    Node *value = fetch_interpreter_state(index, bt, locals_addr, osr_buf);
    set_local(index, value);
  }

  // Extract the needed stack entries from the interpreter frame.
  for (index = 0; index < sp(); index++) {
    const Type *type = osr_block->stack_type_at(index);
    if (type != Type::TOP) {
      // Currently the compiler bails out when attempting to on stack replace
      // at a bci with a non-empty stack.  We should not reach here.
      ShouldNotReachHere();
    }
  }

  // End the OSR migration
  make_runtime_call(RC_LEAF, OptoRuntime::osr_end_Type(),
                    CAST_FROM_FN_PTR(address, SharedRuntime::OSR_migration_end),
                    "OSR_migration_end", TypeRawPtr::BOTTOM,
                    osr_buf);

  // Now that the interpreter state is loaded, make sure it will match
  // at execution time what the compiler is expecting now:
  SafePointNode* bad_type_exit = clone_map();
  bad_type_exit->set_control(new (C) RegionNode(1));

  assert(osr_block->flow()->jsrs()->size() == 0, "should be no jsrs live at osr point");
  for (index = 0; index < max_locals; index++) {
    if (stopped())  break;
    Node* l = local(index);
    if (l->is_top())  continue;  // nothing here
    const Type *type = osr_block->local_type_at(index);
    if (type->isa_oopptr() != NULL) {
      if (!live_oops.at(index)) {
        // skip type check for dead oops
        continue;
      }
    }
    if (osr_block->flow()->local_type_at(index)->is_return_address()) {
      // In our current system it's illegal for jsr addresses to be
      // live into an OSR entry point because the compiler performs
      // inlining of jsrs.  ciTypeFlow has a bailout that detect this
      // case and aborts the compile if addresses are live into an OSR
      // entry point.  Because of that we can assume that any address
      // locals at the OSR entry point are dead.  Method liveness
      // isn't precise enought to figure out that they are dead in all
      // cases so simply skip checking address locals all
      // together. Any type check is guaranteed to fail since the
      // interpreter type is the result of a load which might have any
      // value and the expected type is a constant.
      continue;
    }
    set_local(index, check_interpreter_type(l, type, bad_type_exit));
  }

  for (index = 0; index < sp(); index++) {
    if (stopped())  break;
    Node* l = stack(index);
    if (l->is_top())  continue;  // nothing here
    const Type *type = osr_block->stack_type_at(index);
    set_stack(index, check_interpreter_type(l, type, bad_type_exit));
  }

  if (bad_type_exit->control()->req() > 1) {
    // Build an uncommon trap here, if any inputs can be unexpected.
    bad_type_exit->set_control(_gvn.transform( bad_type_exit->control() ));
    record_for_igvn(bad_type_exit->control());
    SafePointNode* types_are_good = map();
    set_map(bad_type_exit);
    // The unexpected type happens because a new edge is active
    // in the CFG, which typeflow had previously ignored.
    // E.g., Object x = coldAtFirst() && notReached()? "str": new Integer(123).
    // This x will be typed as Integer if notReached is not yet linked.
    // It could also happen due to a problem in ciTypeFlow analysis.
    uncommon_trap(Deoptimization::Reason_constraint,
                  Deoptimization::Action_reinterpret);
    set_map(types_are_good);
  }
}

//------------------------------Parse------------------------------------------
// Main parser constructor.
Parse::Parse(JVMState* caller, ciMethod* parse_method, float expected_uses, Parse* parent)
  : _exits(caller), _parent(parent)
{
  // Init some variables
  _caller = caller;
  _method = parse_method;
  _expected_uses = expected_uses;
  _depth = 1 + (caller->has_method() ? caller->depth() : 0);
  _wrote_final = false;
  _alloc_with_final = NULL;
  _entry_bci = InvocationEntryBci;
  _tf = NULL;
  _block = NULL;
  debug_only(_block_count = -1);
  debug_only(_blocks = (Block*)-1);
#ifndef PRODUCT
  if (PrintCompilation || PrintOpto) {
    // Make sure I have an inline tree, so I can print messages about it.
    JVMState* ilt_caller = is_osr_parse() ? caller->caller() : caller;
    InlineTree::find_subtree_from_root(C->ilt(), ilt_caller, parse_method);
  }
  _max_switch_depth = 0;
  _est_switch_depth = 0;
#endif

  _tf = TypeFunc::make(method());
  _iter.reset_to_method(method());
  _flow = method()->get_flow_analysis();
  if (_flow->failing()) {
    C->record_method_not_compilable_all_tiers(_flow->failure_reason());
  }

#ifndef PRODUCT
  if (_flow->has_irreducible_entry()) {
    C->set_parsed_irreducible_loop(true);
  }
#endif

  if (_expected_uses <= 0) {
    _prof_factor = 1;
  } else {
    float prof_total = parse_method->interpreter_invocation_count();
    if (prof_total <= _expected_uses) {
      _prof_factor = 1;
    } else {
      _prof_factor = _expected_uses / prof_total;
    }
  }

  CompileLog* log = C->log();
  if (log != NULL) {
    log->begin_head("parse method='%d' uses='%g'",
                    log->identify(parse_method), expected_uses);
    if (depth() == 1 && C->is_osr_compilation()) {
      log->print(" osr_bci='%d'", C->entry_bci());
    }
    log->stamp();
    log->end_head();
  }

  // Accumulate deoptimization counts.
  // (The range_check and store_check counts are checked elsewhere.)
  ciMethodData* md = method()->method_data();
  for (uint reason = 0; reason < md->trap_reason_limit(); reason++) {
    uint md_count = md->trap_count(reason);
    if (md_count != 0) {
      if (md_count == md->trap_count_limit())
        md_count += md->overflow_trap_count();
      uint total_count = C->trap_count(reason);
      uint old_count   = total_count;
      total_count += md_count;
      // Saturate the add if it overflows.
      if (total_count < old_count || total_count < md_count)
        total_count = (uint)-1;
      C->set_trap_count(reason, total_count);
      if (log != NULL)
        log->elem("observe trap='%s' count='%d' total='%d'",
                  Deoptimization::trap_reason_name(reason),
                  md_count, total_count);
    }
  }
  // Accumulate total sum of decompilations, also.
  C->set_decompile_count(C->decompile_count() + md->decompile_count());

  _count_invocations = C->do_count_invocations();
  _method_data_update = C->do_method_data_update();

  if (log != NULL && method()->has_exception_handlers()) {
    log->elem("observe that='has_exception_handlers'");
  }

  assert(method()->can_be_compiled(),       "Can not parse this method, cutout earlier");
  assert(method()->has_balanced_monitors(), "Can not parse unbalanced monitors, cutout earlier");

  // Always register dependence if JVMTI is enabled, because
  // either breakpoint setting or hotswapping of methods may
  // cause deoptimization.
  if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
    C->dependencies()->assert_evol_method(method());
  }

  methods_seen++;

  // Do some special top-level things.
  if (depth() == 1 && C->is_osr_compilation()) {
    _entry_bci = C->entry_bci();
    _flow = method()->get_osr_flow_analysis(osr_bci());
    if (_flow->failing()) {
      C->record_method_not_compilable(_flow->failure_reason());
#ifndef PRODUCT
      if (PrintOpto && (Verbose || WizardMode)) {
        tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
        if (Verbose) {
          method()->print();
          method()->print_codes();
          _flow->print();
        }
      }
#endif
    }
    _tf = C->tf();     // the OSR entry type is different
  }

#ifdef ASSERT
  if (depth() == 1) {
    assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");
    if (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");
    }
  } else {
    assert(!this->is_osr_parse(), "no recursive OSR");
  }
#endif

  methods_parsed++;
#ifndef PRODUCT
  // add method size here to guarantee that inlined methods are added too
  if (TimeCompiler)
    _total_bytes_compiled += method()->code_size();

  show_parse_info();
#endif

  if (failing()) {
    if (log)  log->done("parse");
    return;
  }

  gvn().set_type(root(), root()->bottom_type());
  gvn().transform(top());

  // Import the results of the ciTypeFlow.
  init_blocks();

  // Merge point for all normal exits
  build_exits();

  // Setup the initial JVM state map.
  SafePointNode* entry_map = create_entry_map();

  // Check for bailouts during map initialization
  if (failing() || entry_map == NULL) {
    if (log)  log->done("parse");
    return;
  }

  Node_Notes* caller_nn = C->default_node_notes();
  // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
  if (DebugInlinedCalls || depth() == 1) {
    C->set_default_node_notes(make_node_notes(caller_nn));
  }

  if (is_osr_parse()) {
    Node* osr_buf = entry_map->in(TypeFunc::Parms+0);
    entry_map->set_req(TypeFunc::Parms+0, top());
    set_map(entry_map);
    load_interpreter_state(osr_buf);
  } else {
    set_map(entry_map);
    do_method_entry();
  }

  // Check for bailouts during method entry.
  if (failing()) {
    if (log)  log->done("parse");
    C->set_default_node_notes(caller_nn);
    return;
  }

  entry_map = map();  // capture any changes performed by method setup code
  assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");

  // We begin parsing as if we have just encountered a jump to the
  // method entry.
  Block* entry_block = start_block();
  assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
  set_map_clone(entry_map);
  merge_common(entry_block, entry_block->next_path_num());

#ifndef PRODUCT
  BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
  set_parse_histogram( parse_histogram_obj );
#endif

  // Parse all the basic blocks.
  do_all_blocks();

  C->set_default_node_notes(caller_nn);

  // Check for bailouts during conversion to graph
  if (failing()) {
    if (log)  log->done("parse");
    return;
  }

  // Fix up all exiting control flow.
  set_map(entry_map);
  do_exits();

  if (log)  log->done("parse nodes='%d' live='%d' memory='%d'",
                      C->unique(), C->live_nodes(), C->node_arena()->used());
}

//---------------------------do_all_blocks-------------------------------------
void Parse::do_all_blocks() {
  bool has_irreducible = flow()->has_irreducible_entry();

  // Walk over all blocks in Reverse Post-Order.
  while (true) {
    bool progress = false;
    for (int rpo = 0; rpo < block_count(); rpo++) {
      Block* block = rpo_at(rpo);

      if (block->is_parsed()) continue;

      if (!block->is_merged()) {
        // Dead block, no state reaches this block
        continue;
      }

      // Prepare to parse this block.
      load_state_from(block);

      if (stopped()) {
        // Block is dead.
        continue;
      }

      blocks_parsed++;

      progress = true;
      if (block->is_loop_head() || block->is_handler() || has_irreducible && !block->is_ready()) {
        // Not all preds have been parsed.  We must build phis everywhere.
        // (Note that dead locals do not get phis built, ever.)
        ensure_phis_everywhere();

        if (block->is_SEL_head() &&
            (UseLoopPredicate || LoopLimitCheck)) {
          // Add predicate to single entry (not irreducible) loop head.
          assert(!block->has_merged_backedge(), "only entry paths should be merged for now");
          // Need correct bci for predicate.
          // It is fine to set it here since do_one_block() will set it anyway.
          set_parse_bci(block->start());
          add_predicate();
          // Add new region for back branches.
          int edges = block->pred_count() - block->preds_parsed() + 1; // +1 for original region
          RegionNode *r = new (C) RegionNode(edges+1);
          _gvn.set_type(r, Type::CONTROL);
          record_for_igvn(r);
          r->init_req(edges, control());
          set_control(r);
          // Add new phis.
          ensure_phis_everywhere();
        }

        // Leave behind an undisturbed copy of the map, for future merges.
        set_map(clone_map());
      }

      if (control()->is_Region() && !block->is_loop_head() && !has_irreducible && !block->is_handler()) {
        // In the absence of irreducible loops, the Region and Phis
        // associated with a merge that doesn't involve a backedge can
        // be simplified now since the RPO parsing order guarantees
        // that any path which was supposed to reach here has already
        // been parsed or must be dead.
        Node* c = control();
        Node* result = _gvn.transform_no_reclaim(control());
        if (c != result && TraceOptoParse) {
          tty->print_cr("Block #%d replace %d with %d", block->rpo(), c->_idx, result->_idx);
        }
        if (result != top()) {
          record_for_igvn(result);
        }
      }

      // Parse the block.
      do_one_block();

      // Check for bailouts.
      if (failing())  return;
    }

    // with irreducible loops multiple passes might be necessary to parse everything
    if (!has_irreducible || !progress) {
      break;
    }
  }

  blocks_seen += block_count();

#ifndef PRODUCT
  // Make sure there are no half-processed blocks remaining.
  // Every remaining unprocessed block is dead and may be ignored now.
  for (int rpo = 0; rpo < block_count(); rpo++) {
    Block* block = rpo_at(rpo);
    if (!block->is_parsed()) {
      if (TraceOptoParse) {
        tty->print_cr("Skipped dead block %d at bci:%d", rpo, block->start());
      }
      assert(!block->is_merged(), "no half-processed blocks");
    }
  }
#endif
}

//-------------------------------build_exits----------------------------------
// Build normal and exceptional exit merge points.
void Parse::build_exits() {
  // make a clone of caller to prevent sharing of side-effects
  _exits.set_map(_exits.clone_map());
  _exits.clean_stack(_exits.sp());
  _exits.sync_jvms();

  RegionNode* region = new (C) RegionNode(1);
  record_for_igvn(region);
  gvn().set_type_bottom(region);
  _exits.set_control(region);

  // Note:  iophi and memphi are not transformed until do_exits.
  Node* iophi  = new (C) PhiNode(region, Type::ABIO);
  Node* memphi = new (C) PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
  gvn().set_type_bottom(iophi);
  gvn().set_type_bottom(memphi);
  _exits.set_i_o(iophi);
  _exits.set_all_memory(memphi);

  // Add a return value to the exit state.  (Do not push it yet.)
  if (tf()->range()->cnt() > TypeFunc::Parms) {
    const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
    // Don't "bind" an unloaded return klass to the ret_phi. If the klass
    // becomes loaded during the subsequent parsing, the loaded and unloaded
    // types will not join when we transform and push in do_exits().
    const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
    if (ret_oop_type && !ret_oop_type->klass()->is_loaded()) {
      ret_type = TypeOopPtr::BOTTOM;
    }
    int         ret_size = type2size[ret_type->basic_type()];
    Node*       ret_phi  = new (C) PhiNode(region, ret_type);
    gvn().set_type_bottom(ret_phi);
    _exits.ensure_stack(ret_size);
    assert((int)(tf()->range()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
    assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
    _exits.set_argument(0, ret_phi);  // here is where the parser finds it
    // Note:  ret_phi is not yet pushed, until do_exits.
  }
}


//----------------------------build_start_state-------------------------------
// Construct a state which contains only the incoming arguments from an
// unknown caller.  The method & bci will be NULL & InvocationEntryBci.
JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
  int        arg_size = tf->domain()->cnt();
  int        max_size = MAX2(arg_size, (int)tf->range()->cnt());
  JVMState*  jvms     = new (this) JVMState(max_size - TypeFunc::Parms);
  SafePointNode* map  = new (this) SafePointNode(max_size, NULL);
  record_for_igvn(map);
  assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
  Node_Notes* old_nn = default_node_notes();
  if (old_nn != NULL && has_method()) {
    Node_Notes* entry_nn = old_nn->clone(this);
    JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
    entry_jvms->set_offsets(0);
    entry_jvms->set_bci(entry_bci());
    entry_nn->set_jvms(entry_jvms);
    set_default_node_notes(entry_nn);
  }
  uint i;
  for (i = 0; i < (uint)arg_size; i++) {
    Node* parm = initial_gvn()->transform(new (this) ParmNode(start, i));
    map->init_req(i, parm);
    // Record all these guys for later GVN.
    record_for_igvn(parm);
  }
  for (; i < map->req(); i++) {
    map->init_req(i, top());
  }
  assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
  set_default_node_notes(old_nn);
  map->set_jvms(jvms);
  jvms->set_map(map);
  return jvms;
}

//-----------------------------make_node_notes---------------------------------
Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
  if (caller_nn == NULL)  return NULL;
  Node_Notes* nn = caller_nn->clone(C);
  JVMState* caller_jvms = nn->jvms();
  JVMState* jvms = new (C) JVMState(method(), caller_jvms);
  jvms->set_offsets(0);
  jvms->set_bci(_entry_bci);
  nn->set_jvms(jvms);
  return nn;
}


//--------------------------return_values--------------------------------------
void Compile::return_values(JVMState* jvms) {
  GraphKit kit(jvms);
  Node* ret = new (this) ReturnNode(TypeFunc::Parms,
                             kit.control(),
                             kit.i_o(),
                             kit.reset_memory(),
                             kit.frameptr(),
                             kit.returnadr());
  // Add zero or 1 return values
  int ret_size = tf()->range()->cnt() - TypeFunc::Parms;
  if (ret_size > 0) {
    kit.inc_sp(-ret_size);  // pop the return value(s)
    kit.sync_jvms();
    ret->add_req(kit.argument(0));
    // Note:  The second dummy edge is not needed by a ReturnNode.
  }
  // bind it to root
  root()->add_req(ret);
  record_for_igvn(ret);
  initial_gvn()->transform_no_reclaim(ret);
}

//------------------------rethrow_exceptions-----------------------------------
// Bind all exception states in the list into a single RethrowNode.
void Compile::rethrow_exceptions(JVMState* jvms) {
  GraphKit kit(jvms);
  if (!kit.has_exceptions())  return;  // nothing to generate
  // Load my combined exception state into the kit, with all phis transformed:
  SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
  Node* ex_oop = kit.use_exception_state(ex_map);
  RethrowNode* exit = new (this) RethrowNode(kit.control(),
                                      kit.i_o(), kit.reset_memory(),
                                      kit.frameptr(), kit.returnadr(),
                                      // like a return but with exception input
                                      ex_oop);
  // bind to root
  root()->add_req(exit);
  record_for_igvn(exit);
  initial_gvn()->transform_no_reclaim(exit);
}

//---------------------------do_exceptions-------------------------------------
// Process exceptions arising from the current bytecode.
// Send caught exceptions to the proper handler within this method.
// Unhandled exceptions feed into _exit.
void Parse::do_exceptions() {
  if (!has_exceptions())  return;

  if (failing()) {
    // Pop them all off and throw them away.
    while (pop_exception_state() != NULL) ;
    return;
  }

  PreserveJVMState pjvms(this, false);

  SafePointNode* ex_map;
  while ((ex_map = pop_exception_state()) != NULL) {
    if (!method()->has_exception_handlers()) {
      // Common case:  Transfer control outward.
      // Doing it this early allows the exceptions to common up
      // even between adjacent method calls.
      throw_to_exit(ex_map);
    } else {
      // Have to look at the exception first.
      assert(stopped(), "catch_inline_exceptions trashes the map");
      catch_inline_exceptions(ex_map);
      stop_and_kill_map();      // we used up this exception state; kill it
    }
  }

  // We now return to our regularly scheduled program:
}

//---------------------------throw_to_exit-------------------------------------
// Merge the given map into an exception exit from this method.
// The exception exit will handle any unlocking of receiver.
// The ex_oop must be saved within the ex_map, unlike merge_exception.
void Parse::throw_to_exit(SafePointNode* ex_map) {
  // Pop the JVMS to (a copy of) the caller.
  GraphKit caller;
  caller.set_map_clone(_caller->map());
  caller.set_bci(_caller->bci());
  caller.set_sp(_caller->sp());
  // Copy out the standard machine state:
  for (uint i = 0; i < TypeFunc::Parms; i++) {
    caller.map()->set_req(i, ex_map->in(i));
  }
  // ...and the exception:
  Node*          ex_oop        = saved_ex_oop(ex_map);
  SafePointNode* caller_ex_map = caller.make_exception_state(ex_oop);
  // Finally, collect the new exception state in my exits:
  _exits.add_exception_state(caller_ex_map);
}

//------------------------------do_exits---------------------------------------
void Parse::do_exits() {
  set_parse_bci(InvocationEntryBci);

  // Now peephole on the return bits
  Node* region = _exits.control();
  _exits.set_control(gvn().transform(region));

  Node* iophi = _exits.i_o();
  _exits.set_i_o(gvn().transform(iophi));

  if (wrote_final()) {
    // This method (which must be a constructor by the rules of Java)
    // wrote a final.  The effects of all initializations must be
    // committed to memory before any code after the constructor
    // publishes the reference to the newly constructor object.
    // Rather than wait for the publication, we simply block the
    // writes here.  Rather than put a barrier on only those writes
    // which are required to complete, we force all writes to complete.
    //
    // "All bets are off" unless the first publication occurs after a
    // normal return from the constructor.  We do not attempt to detect
    // such unusual early publications.  But no barrier is needed on
    // exceptional returns, since they cannot publish normally.
    //
    _exits.insert_mem_bar(Op_MemBarRelease, alloc_with_final());
#ifndef PRODUCT
    if (PrintOpto && (Verbose || WizardMode)) {
      method()->print_name();
      tty->print_cr(" writes finals and needs a memory barrier");
    }
#endif
  }

  for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
    // transform each slice of the original memphi:
    mms.set_memory(_gvn.transform(mms.memory()));
  }

  if (tf()->range()->cnt() > TypeFunc::Parms) {
    const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
    Node*       ret_phi  = _gvn.transform( _exits.argument(0) );
    assert(_exits.control()->is_top() || !_gvn.type(ret_phi)->empty(), "return value must be well defined");
    _exits.push_node(ret_type->basic_type(), ret_phi);
  }

  // Note:  Logic for creating and optimizing the ReturnNode is in Compile.

  // Unlock along the exceptional paths.
  // This is done late so that we can common up equivalent exceptions
  // (e.g., null checks) arising from multiple points within this method.
  // See GraphKit::add_exception_state, which performs the commoning.
  bool do_synch = method()->is_synchronized() && GenerateSynchronizationCode;

  // record exit from a method if compiled while Dtrace is turned on.
  if (do_synch || C->env()->dtrace_method_probes()) {
    // First move the exception list out of _exits:
    GraphKit kit(_exits.transfer_exceptions_into_jvms());
    SafePointNode* normal_map = kit.map();  // keep this guy safe
    // Now re-collect the exceptions into _exits:
    SafePointNode* ex_map;
    while ((ex_map = kit.pop_exception_state()) != NULL) {
      Node* ex_oop = kit.use_exception_state(ex_map);
      // Force the exiting JVM state to have this method at InvocationEntryBci.
      // The exiting JVM state is otherwise a copy of the calling JVMS.
      JVMState* caller = kit.jvms();
      JVMState* ex_jvms = caller->clone_shallow(C);
      ex_jvms->set_map(kit.clone_map());
      ex_jvms->map()->set_jvms(ex_jvms);
      ex_jvms->set_bci(   InvocationEntryBci);
      kit.set_jvms(ex_jvms);
      if (do_synch) {
        // Add on the synchronized-method box/object combo
        kit.map()->push_monitor(_synch_lock);
        // Unlock!
        kit.shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
      }
      if (C->env()->dtrace_method_probes()) {
        kit.make_dtrace_method_exit(method());
      }
      // Done with exception-path processing.
      ex_map = kit.make_exception_state(ex_oop);
      assert(ex_jvms->same_calls_as(ex_map->jvms()), "sanity");
      // Pop the last vestige of this method:
      ex_map->set_jvms(caller->clone_shallow(C));
      ex_map->jvms()->set_map(ex_map);
      _exits.push_exception_state(ex_map);
    }
    assert(_exits.map() == normal_map, "keep the same return state");
  }

  {
    // Capture very early exceptions (receiver null checks) from caller JVMS
    GraphKit caller(_caller);
    SafePointNode* ex_map;
    while ((ex_map = caller.pop_exception_state()) != NULL) {
      _exits.add_exception_state(ex_map);
    }
  }
}

//-----------------------------create_entry_map-------------------------------
// Initialize our parser map to contain the types at method entry.
// For OSR, the map contains a single RawPtr parameter.
// Initial monitor locking for sync. methods is performed by do_method_entry.
SafePointNode* Parse::create_entry_map() {
  // Check for really stupid bail-out cases.
  uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
  if (len >= 32760) {
    C->record_method_not_compilable_all_tiers("too many local variables");
    return NULL;
  }

  // If this is an inlined method, we may have to do a receiver null check.
  if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
    GraphKit kit(_caller);
    kit.null_check_receiver_before_call(method());
    _caller = kit.transfer_exceptions_into_jvms();
    if (kit.stopped()) {
      _exits.add_exception_states_from(_caller);
      _exits.set_jvms(_caller);
      return NULL;
    }
  }

  assert(method() != NULL, "parser must have a method");

  // Create an initial safepoint to hold JVM state during parsing
  JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : NULL);
  set_map(new (C) SafePointNode(len, jvms));
  jvms->set_map(map());
  record_for_igvn(map());
  assert(jvms->endoff() == len, "correct jvms sizing");

  SafePointNode* inmap = _caller->map();
  assert(inmap != NULL, "must have inmap");

  uint i;

  // Pass thru the predefined input parameters.
  for (i = 0; i < TypeFunc::Parms; i++) {
    map()->init_req(i, inmap->in(i));
  }

  if (depth() == 1) {
    assert(map()->memory()->Opcode() == Op_Parm, "");
    // Insert the memory aliasing node
    set_all_memory(reset_memory());
  }
  assert(merged_memory(), "");

  // Now add the locals which are initially bound to arguments:
  uint arg_size = tf()->domain()->cnt();
  ensure_stack(arg_size - TypeFunc::Parms);  // OSR methods have funny args
  for (i = TypeFunc::Parms; i < arg_size; i++) {
    map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
  }

  // Clear out the rest of the map (locals and stack)
  for (i = arg_size; i < len; i++) {
    map()->init_req(i, top());
  }

  SafePointNode* entry_map = stop();
  return entry_map;
}

//-----------------------------do_method_entry--------------------------------
// Emit any code needed in the pseudo-block before BCI zero.
// The main thing to do is lock the receiver of a synchronized method.
void Parse::do_method_entry() {
  set_parse_bci(InvocationEntryBci); // Pseudo-BCP
  set_sp(0);                      // Java Stack Pointer

  NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )

  if (C->env()->dtrace_method_probes()) {
    make_dtrace_method_entry(method());
  }

  // If the method is synchronized, we need to construct a lock node, attach
  // it to the Start node, and pin it there.
  if (method()->is_synchronized()) {
    // Insert a FastLockNode right after the Start which takes as arguments
    // the current thread pointer, the "this" pointer & the address of the
    // stack slot pair used for the lock.  The "this" pointer is a projection
    // off the start node, but the locking spot has to be constructed by
    // creating a ConLNode of 0, and boxing it with a BoxLockNode.  The BoxLockNode
    // becomes the second argument to the FastLockNode call.  The
    // FastLockNode becomes the new control parent to pin it to the start.

    // Setup Object Pointer
    Node *lock_obj = NULL;
    if(method()->is_static()) {
      ciInstance* mirror = _method->holder()->java_mirror();
      const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
      lock_obj = makecon(t_lock);
    } else {                  // Else pass the "this" pointer,
      lock_obj = local(0);    // which is Parm0 from StartNode
    }
    // Clear out dead values from the debug info.
    kill_dead_locals();
    // Build the FastLockNode
    _synch_lock = shared_lock(lock_obj);
  }

  // Feed profiling data for parameters to the type system so it can
  // propagate it as speculative types
  record_profiled_parameters_for_speculation();

  if (depth() == 1) {
    increment_and_test_invocation_counter(Tier2CompileThreshold);
  }
}

//------------------------------init_blocks------------------------------------
// Initialize our parser map to contain the types/monitors at method entry.
void Parse::init_blocks() {
  // Create the blocks.
  _block_count = flow()->block_count();
  _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);
  Copy::zero_to_bytes(_blocks, sizeof(Block)*_block_count);

  int rpo;

  // Initialize the structs.
  for (rpo = 0; rpo < block_count(); rpo++) {
    Block* block = rpo_at(rpo);
    block->init_node(this, rpo);
  }

  // Collect predecessor and successor information.
  for (rpo = 0; rpo < block_count(); rpo++) {
    Block* block = rpo_at(rpo);
    block->init_graph(this);
  }
}

//-------------------------------init_node-------------------------------------
void Parse::Block::init_node(Parse* outer, int rpo) {
  _flow = outer->flow()->rpo_at(rpo);
  _pred_count = 0;
  _preds_parsed = 0;
  _count = 0;
  assert(pred_count() == 0 && preds_parsed() == 0, "sanity");
  assert(!(is_merged() || is_parsed() || is_handler() || has_merged_backedge()), "sanity");
  assert(_live_locals.size() == 0, "sanity");

  // entry point has additional predecessor
  if (flow()->is_start())  _pred_count++;
  assert(flow()->is_start() == (this == outer->start_block()), "");
}

//-------------------------------init_graph------------------------------------
void Parse::Block::init_graph(Parse* outer) {
  // Create the successor list for this parser block.
  GrowableArray<ciTypeFlow::Block*>* tfs = flow()->successors();
  GrowableArray<ciTypeFlow::Block*>* tfe = flow()->exceptions();
  int ns = tfs->length();
  int ne = tfe->length();
  _num_successors = ns;
  _all_successors = ns+ne;
  _successors = (ns+ne == 0) ? NULL : NEW_RESOURCE_ARRAY(Block*, ns+ne);
  int p = 0;
  for (int i = 0; i < ns+ne; i++) {
    ciTypeFlow::Block* tf2 = (i < ns) ? tfs->at(i) : tfe->at(i-ns);
    Block* block2 = outer->rpo_at(tf2->rpo());
    _successors[i] = block2;

    // Accumulate pred info for the other block, too.
    if (i < ns) {
      block2->_pred_count++;
    } else {
      block2->_is_handler = true;
    }

    #ifdef ASSERT
    // A block's successors must be distinguishable by BCI.
    // That is, no bytecode is allowed to branch to two different
    // clones of the same code location.
    for (int j = 0; j < i; j++) {
      Block* block1 = _successors[j];
      if (block1 == block2)  continue;  // duplicates are OK
      assert(block1->start() != block2->start(), "successors have unique bcis");
    }
    #endif
  }

  // Note: We never call next_path_num along exception paths, so they
  // never get processed as "ready".  Also, the input phis of exception
  // handlers get specially processed, so that
}

//---------------------------successor_for_bci---------------------------------
Parse::Block* Parse::Block::successor_for_bci(int bci) {
  for (int i = 0; i < all_successors(); i++) {
    Block* block2 = successor_at(i);
    if (block2->start() == bci)  return block2;
  }
  // We can actually reach here if ciTypeFlow traps out a block
  // due to an unloaded class, and concurrently with compilation the
  // class is then loaded, so that a later phase of the parser is
  // able to see more of the bytecode CFG.  Or, the flow pass and
  // the parser can have a minor difference of opinion about executability
  // of bytecodes.  For example, "obj.field = null" is executable even
  // if the field's type is an unloaded class; the flow pass used to
  // make a trap for such code.
  return NULL;
}


//-----------------------------stack_type_at-----------------------------------
const Type* Parse::Block::stack_type_at(int i) const {
  return get_type(flow()->stack_type_at(i));
}


//-----------------------------local_type_at-----------------------------------
const Type* Parse::Block::local_type_at(int i) const {
  // Make dead locals fall to bottom.
  if (_live_locals.size() == 0) {
    MethodLivenessResult live_locals = flow()->outer()->method()->liveness_at_bci(start());
    // This bitmap can be zero length if we saw a breakpoint.
    // In such cases, pretend they are all live.
    ((Block*)this)->_live_locals = live_locals;
  }
  if (_live_locals.size() > 0 && !_live_locals.at(i))
    return Type::BOTTOM;

  return get_type(flow()->local_type_at(i));
}


#ifndef PRODUCT

//----------------------------name_for_bc--------------------------------------
// helper method for BytecodeParseHistogram
static const char* name_for_bc(int i) {
  return Bytecodes::is_defined(i) ? Bytecodes::name(Bytecodes::cast(i)) : "xxxunusedxxx";
}

//----------------------------BytecodeParseHistogram------------------------------------
Parse::BytecodeParseHistogram::BytecodeParseHistogram(Parse *p, Compile *c) {
  _parser   = p;
  _compiler = c;
  if( ! _initialized ) { _initialized = true; reset(); }
}

//----------------------------current_count------------------------------------
int Parse::BytecodeParseHistogram::current_count(BPHType bph_type) {
  switch( bph_type ) {
  case BPH_transforms: { return _parser->gvn().made_progress(); }
  case BPH_values:     { return _parser->gvn().made_new_values(); }
  default: { ShouldNotReachHere(); return 0; }
  }
}

//----------------------------initialized--------------------------------------
bool Parse::BytecodeParseHistogram::initialized() { return _initialized; }

//----------------------------reset--------------------------------------------
void Parse::BytecodeParseHistogram::reset() {
  int i = Bytecodes::number_of_codes;
  while (i-- > 0) { _bytecodes_parsed[i] = 0; _nodes_constructed[i] = 0; _nodes_transformed[i] = 0; _new_values[i] = 0; }
}

//----------------------------set_initial_state--------------------------------
// Record info when starting to parse one bytecode
void Parse::BytecodeParseHistogram::set_initial_state( Bytecodes::Code bc ) {
  if( PrintParseStatistics && !_parser->is_osr_parse() ) {
    _initial_bytecode    = bc;
    _initial_node_count  = _compiler->unique();
    _initial_transforms  = current_count(BPH_transforms);
    _initial_values      = current_count(BPH_values);
  }
}

//----------------------------record_change--------------------------------
// Record results of parsing one bytecode
void Parse::BytecodeParseHistogram::record_change() {
  if( PrintParseStatistics && !_parser->is_osr_parse() ) {
    ++_bytecodes_parsed[_initial_bytecode];
    _nodes_constructed [_initial_bytecode] += (_compiler->unique() - _initial_node_count);
    _nodes_transformed [_initial_bytecode] += (current_count(BPH_transforms) - _initial_transforms);
    _new_values        [_initial_bytecode] += (current_count(BPH_values)     - _initial_values);
  }
}


//----------------------------print--------------------------------------------
void Parse::BytecodeParseHistogram::print(float cutoff) {
  ResourceMark rm;
  // print profile
  int total  = 0;
  int i      = 0;
  for( i = 0; i < Bytecodes::number_of_codes; ++i ) { total += _bytecodes_parsed[i]; }
  int abs_sum = 0;
  tty->cr();   //0123456789012345678901234567890123456789012345678901234567890123456789
  tty->print_cr("Histogram of %d parsed bytecodes:", total);
  if( total == 0 ) { return; }
  tty->cr();
  tty->print_cr("absolute:  count of compiled bytecodes of this type");
  tty->print_cr("relative:  percentage contribution to compiled nodes");
  tty->print_cr("nodes   :  Average number of nodes constructed per bytecode");
  tty->print_cr("rnodes  :  Significance towards total nodes constructed, (nodes*relative)");
  tty->print_cr("transforms: Average amount of tranform progress per bytecode compiled");
  tty->print_cr("values  :  Average number of node values improved per bytecode");
  tty->print_cr("name    :  Bytecode name");
  tty->cr();
  tty->print_cr("  absolute  relative   nodes  rnodes  transforms  values   name");
  tty->print_cr("----------------------------------------------------------------------");
  while (--i > 0) {
    int       abs = _bytecodes_parsed[i];
    float     rel = abs * 100.0F / total;
    float   nodes = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_constructed[i])/_bytecodes_parsed[i];
    float  rnodes = _bytecodes_parsed[i] == 0 ? 0 :  rel * nodes;
    float  xforms = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_transformed[i])/_bytecodes_parsed[i];
    float  values = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _new_values       [i])/_bytecodes_parsed[i];
    if (cutoff <= rel) {
      tty->print_cr("%10d  %7.2f%%  %6.1f  %6.2f   %6.1f   %6.1f     %s", abs, rel, nodes, rnodes, xforms, values, name_for_bc(i));
      abs_sum += abs;
    }
  }
  tty->print_cr("----------------------------------------------------------------------");
  float rel_sum = abs_sum * 100.0F / total;
  tty->print_cr("%10d  %7.2f%%    (cutoff = %.2f%%)", abs_sum, rel_sum, cutoff);
  tty->print_cr("----------------------------------------------------------------------");
  tty->cr();
}
#endif

//----------------------------load_state_from----------------------------------
// Load block/map/sp.  But not do not touch iter/bci.
void Parse::load_state_from(Block* block) {
  set_block(block);
  // load the block's JVM state:
  set_map(block->start_map());
  set_sp( block->start_sp());
}


//-----------------------------record_state------------------------------------
void Parse::Block::record_state(Parse* p) {
  assert(!is_merged(), "can only record state once, on 1st inflow");
  assert(start_sp() == p->sp(), "stack pointer must agree with ciTypeFlow");
  set_start_map(p->stop());
}


//------------------------------do_one_block-----------------------------------
void Parse::do_one_block() {
  if (TraceOptoParse) {
    Block *b = block();
    int ns = b->num_successors();
    int nt = b->all_successors();

    tty->print("Parsing block #%d at bci [%d,%d), successors: ",
                  block()->rpo(), block()->start(), block()->limit());
    for (int i = 0; i < nt; i++) {
      tty->print((( i < ns) ? " %d" : " %d(e)"), b->successor_at(i)->rpo());
    }
    if (b->is_loop_head()) tty->print("  lphd");
    tty->print_cr("");
  }

  assert(block()->is_merged(), "must be merged before being parsed");
  block()->mark_parsed();
  ++_blocks_parsed;

  // Set iterator to start of block.
  iter().reset_to_bci(block()->start());

  CompileLog* log = C->log();

  // Parse bytecodes
  while (!stopped() && !failing()) {
    iter().next();

    // Learn the current bci from the iterator:
    set_parse_bci(iter().cur_bci());

    if (bci() == block()->limit()) {
      // Do not walk into the next block until directed by do_all_blocks.
      merge(bci());
      break;
    }
    assert(bci() < block()->limit(), "bci still in block");

    if (log != NULL) {
      // Output an optional context marker, to help place actions
      // that occur during parsing of this BC.  If there is no log
      // output until the next context string, this context string
      // will be silently ignored.
      log->set_context("bc code='%d' bci='%d'", (int)bc(), bci());
    }

    if (block()->has_trap_at(bci())) {
      // We must respect the flow pass's traps, because it will refuse
      // to produce successors for trapping blocks.
      int trap_index = block()->flow()->trap_index();
      assert(trap_index != 0, "trap index must be valid");
      uncommon_trap(trap_index);
      break;
    }

    NOT_PRODUCT( parse_histogram()->set_initial_state(bc()); );

#ifdef ASSERT
    int pre_bc_sp = sp();
    int inputs, depth;
    bool have_se = !stopped() && compute_stack_effects(inputs, depth);
    assert(!have_se || pre_bc_sp >= inputs, err_msg_res("have enough stack to execute this BC: pre_bc_sp=%d, inputs=%d", pre_bc_sp, inputs));
#endif //ASSERT

    do_one_bytecode();

    assert(!have_se || stopped() || failing() || (sp() - pre_bc_sp) == depth,
           err_msg_res("incorrect depth prediction: sp=%d, pre_bc_sp=%d, depth=%d", sp(), pre_bc_sp, depth));

    do_exceptions();

    NOT_PRODUCT( parse_histogram()->record_change(); );

    if (log != NULL)
      log->clear_context();  // skip marker if nothing was printed

    // Fall into next bytecode.  Each bytecode normally has 1 sequential
    // successor which is typically made ready by visiting this bytecode.
    // If the successor has several predecessors, then it is a merge
    // point, starts a new basic block, and is handled like other basic blocks.
  }
}


//------------------------------merge------------------------------------------
void Parse::set_parse_bci(int bci) {
  set_bci(bci);
  Node_Notes* nn = C->default_node_notes();
  if (nn == NULL)  return;

  // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
  if (!DebugInlinedCalls && depth() > 1) {
    return;
  }

  // Update the JVMS annotation, if present.
  JVMState* jvms = nn->jvms();
  if (jvms != NULL && jvms->bci() != bci) {
    // Update the JVMS.
    jvms = jvms->clone_shallow(C);
    jvms->set_bci(bci);
    nn->set_jvms(jvms);
  }
}

//------------------------------merge------------------------------------------
// Merge the current mapping into the basic block starting at bci
void Parse::merge(int target_bci) {
  Block* target = successor_for_bci(target_bci);
  if (target == NULL) { handle_missing_successor(target_bci); return; }
  assert(!target->is_ready(), "our arrival must be expected");
  int pnum = target->next_path_num();
  merge_common(target, pnum);
}

//-------------------------merge_new_path--------------------------------------
// Merge the current mapping into the basic block, using a new path
void Parse::merge_new_path(int target_bci) {
  Block* target = successor_for_bci(target_bci);
  if (target == NULL) { handle_missing_successor(target_bci); return; }
  assert(!target->is_ready(), "new path into frozen graph");
  int pnum = target->add_new_path();
  merge_common(target, pnum);
}

//-------------------------merge_exception-------------------------------------
// Merge the current mapping into the basic block starting at bci
// The ex_oop must be pushed on the stack, unlike throw_to_exit.
void Parse::merge_exception(int target_bci) {
  assert(sp() == 1, "must have only the throw exception on the stack");
  Block* target = successor_for_bci(target_bci);
  if (target == NULL) { handle_missing_successor(target_bci); return; }
  assert(target->is_handler(), "exceptions are handled by special blocks");
  int pnum = target->add_new_path();
  merge_common(target, pnum);
}

//--------------------handle_missing_successor---------------------------------
void Parse::handle_missing_successor(int target_bci) {
#ifndef PRODUCT
  Block* b = block();
  int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
  tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
#endif
  ShouldNotReachHere();
}

//--------------------------merge_common---------------------------------------
void Parse::merge_common(Parse::Block* target, int pnum) {
  if (TraceOptoParse) {
    tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
  }

  // Zap extra stack slots to top
  assert(sp() == target->start_sp(), "");
  clean_stack(sp());

  if (!target->is_merged()) {   // No prior mapping at this bci
    if (TraceOptoParse) { tty->print(" with empty state");  }

    // If this path is dead, do not bother capturing it as a merge.
    // It is "as if" we had 1 fewer predecessors from the beginning.
    if (stopped()) {
      if (TraceOptoParse)  tty->print_cr(", but path is dead and doesn't count");
      return;
    }

    // Record that a new block has been merged.
    ++_blocks_merged;

    // Make a region if we know there are multiple or unpredictable inputs.
    // (Also, if this is a plain fall-through, we might see another region,
    // which must not be allowed into this block's map.)
    if (pnum > PhiNode::Input         // Known multiple inputs.
        || target->is_handler()       // These have unpredictable inputs.
        || target->is_loop_head()     // Known multiple inputs
        || control()->is_Region()) {  // We must hide this guy.

      int current_bci = bci();
      set_parse_bci(target->start()); // Set target bci
      if (target->is_SEL_head()) {
        DEBUG_ONLY( target->mark_merged_backedge(block()); )
        if (target->start() == 0) {
          // Add loop predicate for the special case when
          // there are backbranches to the method entry.
          add_predicate();
        }
      }
      // Add a Region to start the new basic block.  Phis will be added
      // later lazily.
      int edges = target->pred_count();
      if (edges < pnum)  edges = pnum;  // might be a new path!
      RegionNode *r = new (C) RegionNode(edges+1);
      gvn().set_type(r, Type::CONTROL);
      record_for_igvn(r);
      // zap all inputs to NULL for debugging (done in Node(uint) constructor)
      // for (int j = 1; j < edges+1; j++) { r->init_req(j, NULL); }
      r->init_req(pnum, control());
      set_control(r);
      set_parse_bci(current_bci); // Restore bci
    }

    // Convert the existing Parser mapping into a mapping at this bci.
    store_state_to(target);
    assert(target->is_merged(), "do not come here twice");

  } else {                      // Prior mapping at this bci
    if (TraceOptoParse) {  tty->print(" with previous state"); }
#ifdef ASSERT
    if (target->is_SEL_head()) {
      target->mark_merged_backedge(block());
    }
#endif
    // We must not manufacture more phis if the target is already parsed.
    bool nophi = target->is_parsed();

    SafePointNode* newin = map();// Hang on to incoming mapping
    Block* save_block = block(); // Hang on to incoming block;
    load_state_from(target);    // Get prior mapping

    assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
    assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
    assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
    assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");

    // Iterate over my current mapping and the old mapping.
    // Where different, insert Phi functions.
    // Use any existing Phi functions.
    assert(control()->is_Region(), "must be merging to a region");
    RegionNode* r = control()->as_Region();

    // Compute where to merge into
    // Merge incoming control path
    r->init_req(pnum, newin->control());

    if (pnum == 1) {            // Last merge for this Region?
      if (!block()->flow()->is_irreducible_entry()) {
        Node* result = _gvn.transform_no_reclaim(r);
        if (r != result && TraceOptoParse) {
          tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
        }
      }
      record_for_igvn(r);
    }

    // Update all the non-control inputs to map:
    assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
    bool check_elide_phi = target->is_SEL_backedge(save_block);
    for (uint j = 1; j < newin->req(); j++) {
      Node* m = map()->in(j);   // Current state of target.
      Node* n = newin->in(j);   // Incoming change to target state.
      PhiNode* phi;
      if (m->is_Phi() && m->as_Phi()->region() == r)
        phi = m->as_Phi();
      else
        phi = NULL;
      if (m != n) {             // Different; must merge
        switch (j) {
        // Frame pointer and Return Address never changes
        case TypeFunc::FramePtr:// Drop m, use the original value
        case TypeFunc::ReturnAdr:
          break;
        case TypeFunc::Memory:  // Merge inputs to the MergeMem node
          assert(phi == NULL, "the merge contains phis, not vice versa");
          merge_memory_edges(n->as_MergeMem(), pnum, nophi);
          continue;
        default:                // All normal stuff
          if (phi == NULL) {
            const JVMState* jvms = map()->jvms();
            if (EliminateNestedLocks &&
                jvms->is_mon(j) && jvms->is_monitor_box(j)) {
              // BoxLock nodes are not commoning.
              // Use old BoxLock node as merged box.
              assert(newin->jvms()->is_monitor_box(j), "sanity");
              // This assert also tests that nodes are BoxLock.
              assert(BoxLockNode::same_slot(n, m), "sanity");
              C->gvn_replace_by(n, m);
            } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
              phi = ensure_phi(j, nophi);
            }
          }
          break;
        }
      }
      // At this point, n might be top if:
      //  - there is no phi (because TypeFlow detected a conflict), or
      //  - the corresponding control edges is top (a dead incoming path)
      // It is a bug if we create a phi which sees a garbage value on a live path.

      if (phi != NULL) {
        assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
        assert(phi->region() == r, "");
        phi->set_req(pnum, n);  // Then add 'n' to the merge
        if (pnum == PhiNode::Input) {
          // Last merge for this Phi.
          // So far, Phis have had a reasonable type from ciTypeFlow.
          // Now _gvn will join that with the meet of current inputs.
          // BOTTOM is never permissible here, 'cause pessimistically
          // Phis of pointers cannot lose the basic pointer type.
          debug_only(const Type* bt1 = phi->bottom_type());
          assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
          map()->set_req(j, _gvn.transform_no_reclaim(phi));
          debug_only(const Type* bt2 = phi->bottom_type());
          assert(bt2->higher_equal(bt1), "must be consistent with type-flow");
          record_for_igvn(phi);
        }
      }
    } // End of for all values to be merged

    if (pnum == PhiNode::Input &&
        !r->in(0)) {         // The occasional useless Region
      assert(control() == r, "");
      set_control(r->nonnull_req());
    }

    // newin has been subsumed into the lazy merge, and is now dead.
    set_block(save_block);

    stop();                     // done with this guy, for now
  }

  if (TraceOptoParse) {
    tty->print_cr(" on path %d", pnum);
  }

  // Done with this parser state.
  assert(stopped(), "");
}


//--------------------------merge_memory_edges---------------------------------
void Parse::merge_memory_edges(MergeMemNode* n, int pnum, bool nophi) {
  // (nophi means we must not create phis, because we already parsed here)
  assert(n != NULL, "");
  // Merge the inputs to the MergeMems
  MergeMemNode* m = merged_memory();

  assert(control()->is_Region(), "must be merging to a region");
  RegionNode* r = control()->as_Region();

  PhiNode* base = NULL;
  MergeMemNode* remerge = NULL;
  for (MergeMemStream mms(m, n); mms.next_non_empty2(); ) {
    Node *p = mms.force_memory();
    Node *q = mms.memory2();
    if (mms.is_empty() && nophi) {
      // Trouble:  No new splits allowed after a loop body is parsed.
      // Instead, wire the new split into a MergeMem on the backedge.
      // The optimizer will sort it out, slicing the phi.
      if (remerge == NULL) {
        assert(base != NULL, "");
        assert(base->in(0) != NULL, "should not be xformed away");
        remerge = MergeMemNode::make(C, base->in(pnum));
        gvn().set_type(remerge, Type::MEMORY);
        base->set_req(pnum, remerge);
      }
      remerge->set_memory_at(mms.alias_idx(), q);
      continue;
    }
    assert(!q->is_MergeMem(), "");
    PhiNode* phi;
    if (p != q) {
      phi = ensure_memory_phi(mms.alias_idx(), nophi);
    } else {
      if (p->is_Phi() && p->as_Phi()->region() == r)
        phi = p->as_Phi();
      else
        phi = NULL;
    }
    // Insert q into local phi
    if (phi != NULL) {
      assert(phi->region() == r, "");
      p = phi;
      phi->set_req(pnum, q);
      if (mms.at_base_memory()) {
        base = phi;  // delay transforming it
      } else if (pnum == 1) {
        record_for_igvn(phi);
        p = _gvn.transform_no_reclaim(phi);
      }
      mms.set_memory(p);// store back through the iterator
    }
  }
  // Transform base last, in case we must fiddle with remerging.
  if (base != NULL && pnum == 1) {
    record_for_igvn(base);
    m->set_base_memory( _gvn.transform_no_reclaim(base) );
  }
}


//------------------------ensure_phis_everywhere-------------------------------
void Parse::ensure_phis_everywhere() {
  ensure_phi(TypeFunc::I_O);

  // Ensure a phi on all currently known memories.
  for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
    ensure_memory_phi(mms.alias_idx());
    debug_only(mms.set_memory());  // keep the iterator happy
  }

  // Note:  This is our only chance to create phis for memory slices.
  // If we miss a slice that crops up later, it will have to be
  // merged into the base-memory phi that we are building here.
  // Later, the optimizer will comb out the knot, and build separate
  // phi-loops for each memory slice that matters.

  // Monitors must nest nicely and not get confused amongst themselves.
  // Phi-ify everything up to the monitors, though.
  uint monoff = map()->jvms()->monoff();
  uint nof_monitors = map()->jvms()->nof_monitors();

  assert(TypeFunc::Parms == map()->jvms()->locoff(), "parser map should contain only youngest jvms");
  bool check_elide_phi = block()->is_SEL_head();
  for (uint i = TypeFunc::Parms; i < monoff; i++) {
    if (!check_elide_phi || !block()->can_elide_SEL_phi(i)) {
      ensure_phi(i);
    }
  }

  // Even monitors need Phis, though they are well-structured.
  // This is true for OSR methods, and also for the rare cases where
  // a monitor object is the subject of a replace_in_map operation.
  // See bugs 4426707 and 5043395.
  for (uint m = 0; m < nof_monitors; m++) {
    ensure_phi(map()->jvms()->monitor_obj_offset(m));
  }
}


//-----------------------------add_new_path------------------------------------
// Add a previously unaccounted predecessor to this block.
int Parse::Block::add_new_path() {
  // If there is no map, return the lowest unused path number.
  if (!is_merged())  return pred_count()+1;  // there will be a map shortly

  SafePointNode* map = start_map();
  if (!map->control()->is_Region())
    return pred_count()+1;  // there may be a region some day
  RegionNode* r = map->control()->as_Region();

  // Add new path to the region.
  uint pnum = r->req();
  r->add_req(NULL);

  for (uint i = 1; i < map->req(); i++) {
    Node* n = map->in(i);
    if (i == TypeFunc::Memory) {
      // Ensure a phi on all currently known memories.
      for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
        Node* phi = mms.memory();
        if (phi->is_Phi() && phi->as_Phi()->region() == r) {
          assert(phi->req() == pnum, "must be same size as region");
          phi->add_req(NULL);
        }
      }
    } else {
      if (n->is_Phi() && n->as_Phi()->region() == r) {
        assert(n->req() == pnum, "must be same size as region");
        n->add_req(NULL);
      }
    }
  }

  return pnum;
}

//------------------------------ensure_phi-------------------------------------
// Turn the idx'th entry of the current map into a Phi
PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
  SafePointNode* map = this->map();
  Node* region = map->control();
  assert(region->is_Region(), "");

  Node* o = map->in(idx);
  assert(o != NULL, "");

  if (o == top())  return NULL; // TOP always merges into TOP

  if (o->is_Phi() && o->as_Phi()->region() == region) {
    return o->as_Phi();
  }

  // Now use a Phi here for merging
  assert(!nocreate, "Cannot build a phi for a block already parsed.");
  const JVMState* jvms = map->jvms();
  const Type* t;
  if (jvms->is_loc(idx)) {
    t = block()->local_type_at(idx - jvms->locoff());
  } else if (jvms->is_stk(idx)) {
    t = block()->stack_type_at(idx - jvms->stkoff());
  } else if (jvms->is_mon(idx)) {
    assert(!jvms->is_monitor_box(idx), "no phis for boxes");
    t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
  } else if ((uint)idx < TypeFunc::Parms) {
    t = o->bottom_type();  // Type::RETURN_ADDRESS or such-like.
  } else {
    assert(false, "no type information for this phi");
  }

  // If the type falls to bottom, then this must be a local that
  // is mixing ints and oops or some such.  Forcing it to top
  // makes it go dead.
  if (t == Type::BOTTOM) {
    map->set_req(idx, top());
    return NULL;
  }

  // Do not create phis for top either.
  // A top on a non-null control flow must be an unused even after the.phi.
  if (t == Type::TOP || t == Type::HALF) {
    map->set_req(idx, top());
    return NULL;
  }

  PhiNode* phi = PhiNode::make(region, o, t);
  gvn().set_type(phi, t);
  if (C->do_escape_analysis()) record_for_igvn(phi);
  map->set_req(idx, phi);
  return phi;
}

//--------------------------ensure_memory_phi----------------------------------
// Turn the idx'th slice of the current memory into a Phi
PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
  MergeMemNode* mem = merged_memory();
  Node* region = control();
  assert(region->is_Region(), "");

  Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
  assert(o != NULL && o != top(), "");

  PhiNode* phi;
  if (o->is_Phi() && o->as_Phi()->region() == region) {
    phi = o->as_Phi();
    if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
      // clone the shared base memory phi to make a new memory split
      assert(!nocreate, "Cannot build a phi for a block already parsed.");
      const Type* t = phi->bottom_type();
      const TypePtr* adr_type = C->get_adr_type(idx);
      phi = phi->slice_memory(adr_type);
      gvn().set_type(phi, t);
    }
    return phi;
  }

  // Now use a Phi here for merging
  assert(!nocreate, "Cannot build a phi for a block already parsed.");
  const Type* t = o->bottom_type();
  const TypePtr* adr_type = C->get_adr_type(idx);
  phi = PhiNode::make(region, o, t, adr_type);
  gvn().set_type(phi, t);
  if (idx == Compile::AliasIdxBot)
    mem->set_base_memory(phi);
  else
    mem->set_memory_at(idx, phi);
  return phi;
}

//------------------------------call_register_finalizer-----------------------
// Check the klass of the receiver and call register_finalizer if the
// class need finalization.
void Parse::call_register_finalizer() {
  Node* receiver = local(0);
  assert(receiver != NULL && receiver->bottom_type()->isa_instptr() != NULL,
         "must have non-null instance type");

  const TypeInstPtr *tinst = receiver->bottom_type()->isa_instptr();
  if (tinst != NULL && tinst->klass()->is_loaded() && !tinst->klass_is_exact()) {
    // The type isn't known exactly so see if CHA tells us anything.
    ciInstanceKlass* ik = tinst->klass()->as_instance_klass();
    if (!Dependencies::has_finalizable_subclass(ik)) {
      // No finalizable subclasses so skip the dynamic check.
      C->dependencies()->assert_has_no_finalizable_subclasses(ik);
      return;
    }
  }

  // Insert a dynamic test for whether the instance needs
  // finalization.  In general this will fold up since the concrete
  // class is often visible so the access flags are constant.
  Node* klass_addr = basic_plus_adr( receiver, receiver, oopDesc::klass_offset_in_bytes() );
  Node* klass = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), klass_addr, TypeInstPtr::KLASS) );

  Node* access_flags_addr = basic_plus_adr(klass, klass, in_bytes(Klass::access_flags_offset()));
  Node* access_flags = make_load(NULL, access_flags_addr, TypeInt::INT, T_INT);

  Node* mask  = _gvn.transform(new (C) AndINode(access_flags, intcon(JVM_ACC_HAS_FINALIZER)));
  Node* check = _gvn.transform(new (C) CmpINode(mask, intcon(0)));
  Node* test  = _gvn.transform(new (C) BoolNode(check, BoolTest::ne));

  IfNode* iff = create_and_map_if(control(), test, PROB_MAX, COUNT_UNKNOWN);

  RegionNode* result_rgn = new (C) RegionNode(3);
  record_for_igvn(result_rgn);

  Node *skip_register = _gvn.transform(new (C) IfFalseNode(iff));
  result_rgn->init_req(1, skip_register);

  Node *needs_register = _gvn.transform(new (C) IfTrueNode(iff));
  set_control(needs_register);
  if (stopped()) {
    // There is no slow path.
    result_rgn->init_req(2, top());
  } else {
    Node *call = make_runtime_call(RC_NO_LEAF,
                                   OptoRuntime::register_finalizer_Type(),
                                   OptoRuntime::register_finalizer_Java(),
                                   NULL, TypePtr::BOTTOM,
                                   receiver);
    make_slow_call_ex(call, env()->Throwable_klass(), true);

    Node* fast_io  = call->in(TypeFunc::I_O);
    Node* fast_mem = call->in(TypeFunc::Memory);
    // These two phis are pre-filled with copies of of the fast IO and Memory
    Node* io_phi   = PhiNode::make(result_rgn, fast_io,  Type::ABIO);
    Node* mem_phi  = PhiNode::make(result_rgn, fast_mem, Type::MEMORY, TypePtr::BOTTOM);

    result_rgn->init_req(2, control());
    io_phi    ->init_req(2, i_o());
    mem_phi   ->init_req(2, reset_memory());

    set_all_memory( _gvn.transform(mem_phi) );
    set_i_o(        _gvn.transform(io_phi) );
  }

  set_control( _gvn.transform(result_rgn) );
}

//------------------------------return_current---------------------------------
// Append current _map to _exit_return
void Parse::return_current(Node* value) {
  if (RegisterFinalizersAtInit &&
      method()->intrinsic_id() == vmIntrinsics::_Object_init) {
    call_register_finalizer();
  }

  // Do not set_parse_bci, so that return goo is credited to the return insn.
  set_bci(InvocationEntryBci);
  if (method()->is_synchronized() && GenerateSynchronizationCode) {
    shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
  }
  if (C->env()->dtrace_method_probes()) {
    make_dtrace_method_exit(method());
  }
  SafePointNode* exit_return = _exits.map();
  exit_return->in( TypeFunc::Control  )->add_req( control() );
  exit_return->in( TypeFunc::I_O      )->add_req( i_o    () );
  Node *mem = exit_return->in( TypeFunc::Memory   );
  for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
    if (mms.is_empty()) {
      // get a copy of the base memory, and patch just this one input
      const TypePtr* adr_type = mms.adr_type(C);
      Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
      assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
      gvn().set_type_bottom(phi);
      phi->del_req(phi->req()-1);  // prepare to re-patch
      mms.set_memory(phi);
    }
    mms.memory()->add_req(mms.memory2());
  }

  // frame pointer is always same, already captured
  if (value != NULL) {
    // If returning oops to an interface-return, there is a silent free
    // cast from oop to interface allowed by the Verifier.  Make it explicit
    // here.
    Node* phi = _exits.argument(0);
    const TypeInstPtr *tr = phi->bottom_type()->isa_instptr();
    if( tr && tr->klass()->is_loaded() &&
        tr->klass()->is_interface() ) {
      const TypeInstPtr *tp = value->bottom_type()->isa_instptr();
      if (tp && tp->klass()->is_loaded() &&
          !tp->klass()->is_interface()) {
        // sharpen the type eagerly; this eases certain assert checking
        if (tp->higher_equal(TypeInstPtr::NOTNULL))
          tr = tr->join(TypeInstPtr::NOTNULL)->is_instptr();
        value = _gvn.transform(new (C) CheckCastPPNode(0,value,tr));
      }
    }
    phi->add_req(value);
  }

  stop_and_kill_map();          // This CFG path dies here
}


//------------------------------add_safepoint----------------------------------
void Parse::add_safepoint() {
  // See if we can avoid this safepoint.  No need for a SafePoint immediately
  // after a Call (except Leaf Call) or another SafePoint.
  Node *proj = control();
  bool add_poll_param = SafePointNode::needs_polling_address_input();
  uint parms = add_poll_param ? TypeFunc::Parms+1 : TypeFunc::Parms;
  if( proj->is_Proj() ) {
    Node *n0 = proj->in(0);
    if( n0->is_Catch() ) {
      n0 = n0->in(0)->in(0);
      assert( n0->is_Call(), "expect a call here" );
    }
    if( n0->is_Call() ) {
      if( n0->as_Call()->guaranteed_safepoint() )
        return;
    } else if( n0->is_SafePoint() && n0->req() >= parms ) {
      return;
    }
  }

  // Clear out dead values from the debug info.
  kill_dead_locals();

  // Clone the JVM State
  SafePointNode *sfpnt = new (C) SafePointNode(parms, NULL);

  // Capture memory state BEFORE a SafePoint.  Since we can block at a
  // SafePoint we need our GC state to be safe; i.e. we need all our current
  // write barriers (card marks) to not float down after the SafePoint so we
  // must read raw memory.  Likewise we need all oop stores to match the card
  // marks.  If deopt can happen, we need ALL stores (we need the correct JVM
  // state on a deopt).

  // We do not need to WRITE the memory state after a SafePoint.  The control
  // edge will keep card-marks and oop-stores from floating up from below a
  // SafePoint and our true dependency added here will keep them from floating
  // down below a SafePoint.

  // Clone the current memory state
  Node* mem = MergeMemNode::make(C, map()->memory());

  mem = _gvn.transform(mem);

  // Pass control through the safepoint
  sfpnt->init_req(TypeFunc::Control  , control());
  // Fix edges normally used by a call
  sfpnt->init_req(TypeFunc::I_O      , top() );
  sfpnt->init_req(TypeFunc::Memory   , mem   );
  sfpnt->init_req(TypeFunc::ReturnAdr, top() );
  sfpnt->init_req(TypeFunc::FramePtr , top() );

  // Create a node for the polling address
  if( add_poll_param ) {
    Node *polladr = ConPNode::make(C, (address)os::get_polling_page());
    sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
  }

  // Fix up the JVM State edges
  add_safepoint_edges(sfpnt);
  Node *transformed_sfpnt = _gvn.transform(sfpnt);
  set_control(transformed_sfpnt);

  // Provide an edge from root to safepoint.  This makes the safepoint
  // appear useful until the parse has completed.
  if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
    assert(C->root() != NULL, "Expect parse is still valid");
    C->root()->add_prec(transformed_sfpnt);
  }
}

#ifndef PRODUCT
//------------------------show_parse_info--------------------------------------
void Parse::show_parse_info() {
  InlineTree* ilt = NULL;
  if (C->ilt() != NULL) {
    JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
    ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
  }
  if (PrintCompilation && Verbose) {
    if (depth() == 1) {
      if( ilt->count_inlines() ) {
        tty->print("    __inlined %d (%d bytes)", ilt->count_inlines(),
                     ilt->count_inline_bcs());
        tty->cr();
      }
    } else {
      if (method()->is_synchronized())         tty->print("s");
      if (method()->has_exception_handlers())  tty->print("!");
      // Check this is not the final compiled version
      if (C->trap_can_recompile()) {
        tty->print("-");
      } else {
        tty->print(" ");
      }
      method()->print_short_name();
      if (is_osr_parse()) {
        tty->print(" @ %d", osr_bci());
      }
      tty->print(" (%d bytes)",method()->code_size());
      if (ilt->count_inlines()) {
        tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
                   ilt->count_inline_bcs());
      }
      tty->cr();
    }
  }
  if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
    // Print that we succeeded; suppress this message on the first osr parse.

    if (method()->is_synchronized())         tty->print("s");
    if (method()->has_exception_handlers())  tty->print("!");
    // Check this is not the final compiled version
    if (C->trap_can_recompile() && depth() == 1) {
      tty->print("-");
    } else {
      tty->print(" ");
    }
    if( depth() != 1 ) { tty->print("   "); }  // missing compile count
    for (int i = 1; i < depth(); ++i) { tty->print("  "); }
    method()->print_short_name();
    if (is_osr_parse()) {
      tty->print(" @ %d", osr_bci());
    }
    if (ilt->caller_bci() != -1) {
      tty->print(" @ %d", ilt->caller_bci());
    }
    tty->print(" (%d bytes)",method()->code_size());
    if (ilt->count_inlines()) {
      tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
                 ilt->count_inline_bcs());
    }
    tty->cr();
  }
}


//------------------------------dump-------------------------------------------
// Dump information associated with the bytecodes of current _method
void Parse::dump() {
  if( method() != NULL ) {
    // Iterate over bytecodes
    ciBytecodeStream iter(method());
    for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
      dump_bci( iter.cur_bci() );
      tty->cr();
    }
  }
}

// Dump information associated with a byte code index, 'bci'
void Parse::dump_bci(int bci) {
  // Output info on merge-points, cloning, and within _jsr..._ret
  // NYI
  tty->print(" bci:%d", bci);
}

#endif

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