Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright (c) 1998, 2012, Oracle and/or its affiliates. All rights reserved.

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

  *

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

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

  * published by the Free Software Foundation.

  *

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

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

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

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

  * accompanied this code).

  *

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

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

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

  *

  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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

  * questions.

  *

  */

 #include "precompiled.hpp"

 #include "ci/ciReplay.hpp"

 #include "classfile/systemDictionary.hpp"

 #include "classfile/vmSymbols.hpp"

 #include "compiler/compileBroker.hpp"

 #include "compiler/compileLog.hpp"

 #include "interpreter/linkResolver.hpp"

 #include "oops/objArrayKlass.hpp"

 #include "opto/callGenerator.hpp"

 #include "opto/parse.hpp"

 #include "runtime/handles.inline.hpp"

 //=============================================================================

 //------------------------------InlineTree-------------------------------------

 InlineTree::InlineTree(Compile* c,

                        const InlineTree *caller_tree, ciMethod* callee,

                        JVMState* caller_jvms, int caller_bci,

                        float site_invoke_ratio, int max_inline_level) :

   C(c),

   _caller_jvms(caller_jvms),

   _caller_tree((InlineTree*) caller_tree),

   _method(callee),

   _site_invoke_ratio(site_invoke_ratio),

   _max_inline_level(max_inline_level),

   _count_inline_bcs(method()->code_size_for_inlining()),

   _subtrees(c->comp_arena(), 2, 0, NULL),

   _msg(NULL)

 {

   NOT_PRODUCT(_count_inlines = 0;)

   if (_caller_jvms != NULL) {

     // Keep a private copy of the caller_jvms:

     _caller_jvms = new (C) JVMState(caller_jvms->method(), caller_tree->caller_jvms());

     _caller_jvms->set_bci(caller_jvms->bci());

     assert(!caller_jvms->should_reexecute(), "there should be no reexecute bytecode with inlining");

   }

   assert(_caller_jvms->same_calls_as(caller_jvms), "consistent JVMS");

   assert((caller_tree == NULL ? 0 : caller_tree->stack_depth() + 1) == stack_depth(), "correct (redundant) depth parameter");

   assert(caller_bci == this->caller_bci(), "correct (redundant) bci parameter");

   if (UseOldInlining) {

     // Update hierarchical counts, count_inline_bcs() and count_inlines()

     InlineTree *caller = (InlineTree *)caller_tree;

     for( ; caller != NULL; caller = ((InlineTree *)(caller->caller_tree())) ) {

       caller->_count_inline_bcs += count_inline_bcs();

       NOT_PRODUCT(caller->_count_inlines++;)

     }

   }

 }

 InlineTree::InlineTree(Compile* c, ciMethod* callee_method, JVMState* caller_jvms,

                        float site_invoke_ratio, int max_inline_level) :

   C(c),

   _caller_jvms(caller_jvms),

   _caller_tree(NULL),

   _method(callee_method),

   _site_invoke_ratio(site_invoke_ratio),

   _max_inline_level(max_inline_level),

   _count_inline_bcs(method()->code_size()),

   _msg(NULL)

 {

   NOT_PRODUCT(_count_inlines = 0;)

   assert(!UseOldInlining, "do not use for old stuff");

 }

 /**

  *  Return true when EA is ON and a java constructor is called or

  *  a super constructor is called from an inlined java constructor.

  *  Also return true for boxing methods.

  */

 static bool is_init_with_ea(ciMethod* callee_method,

                             ciMethod* caller_method, Compile* C) {

   if (!C->do_escape_analysis() || !EliminateAllocations) {

     return false; // EA is off

   }

   if (callee_method->is_initializer()) {

     return true; // constuctor

   }

   if (caller_method->is_initializer() &&

       caller_method != C->method() &&

       caller_method->holder()->is_subclass_of(callee_method->holder())) {

     return true; // super constructor is called from inlined constructor

   }

   if (C->eliminate_boxing() && callee_method->is_boxing_method()) {

     return true;

   }

   return false;

 }

 /**

  *  Force inlining unboxing accessor.

  */

 static bool is_unboxing_method(ciMethod* callee_method, Compile* C) {

   return C->eliminate_boxing() && callee_method->is_unboxing_method();

 }

 // positive filter: should callee be inlined?

 bool InlineTree::should_inline(ciMethod* callee_method, ciMethod* caller_method,

                                int caller_bci, ciCallProfile& profile,

                                WarmCallInfo* wci_result) {

   // Allows targeted inlining

   if(callee_method->should_inline()) {

     *wci_result = *(WarmCallInfo::always_hot());

     if (C->print_inlining() && Verbose) {

       CompileTask::print_inline_indent(inline_level());

       tty->print_cr("Inlined method is hot: ");

     }

     set_msg("force inline by CompilerOracle");

     return true;

   }

   int size = callee_method->code_size_for_inlining();

   // Check for too many throws (and not too huge)

   if(callee_method->interpreter_throwout_count() > InlineThrowCount &&

      size < InlineThrowMaxSize ) {

     wci_result->set_profit(wci_result->profit() * 100);

     if (C->print_inlining() && Verbose) {

       CompileTask::print_inline_indent(inline_level());

       tty->print_cr("Inlined method with many throws (throws=%d):", callee_method->interpreter_throwout_count());

     }

     set_msg("many throws");

     return true;

   }

   if (!UseOldInlining) {

     set_msg("!UseOldInlining");

     return true;  // size and frequency are represented in a new way

   }

   int default_max_inline_size = C->max_inline_size();

   int inline_small_code_size  = InlineSmallCode / 4;

   int max_inline_size         = default_max_inline_size;

   int call_site_count  = method()->scale_count(profile.count());

   int invoke_count     = method()->interpreter_invocation_count();

   assert(invoke_count != 0, "require invocation count greater than zero");

   int freq = call_site_count / invoke_count;

   // bump the max size if the call is frequent

   if ((freq >= InlineFrequencyRatio) ||

       (call_site_count >= InlineFrequencyCount) ||

       is_unboxing_method(callee_method, C) ||

       is_init_with_ea(callee_method, caller_method, C)) {

     max_inline_size = C->freq_inline_size();

     if (size <= max_inline_size && TraceFrequencyInlining) {

       CompileTask::print_inline_indent(inline_level());

       tty->print_cr("Inlined frequent method (freq=%d count=%d):", freq, call_site_count);

       CompileTask::print_inline_indent(inline_level());

       callee_method->print();

       tty->cr();

     }

   } else {

     // Not hot.  Check for medium-sized pre-existing nmethod at cold sites.

     if (callee_method->has_compiled_code() &&

         callee_method->instructions_size() > inline_small_code_size) {

       set_msg("already compiled into a medium method");

       return false;

     }

   }

   if (size > max_inline_size) {

     if (max_inline_size > default_max_inline_size) {

       set_msg("hot method too big");

     } else {

       set_msg("too big");

     }

     return false;

   }

   return true;

 }

 // negative filter: should callee NOT be inlined?

 bool InlineTree::should_not_inline(ciMethod *callee_method,

                                    ciMethod* caller_method,

                                    JVMState* jvms,

                                    WarmCallInfo* wci_result) {

   const char* fail_msg = NULL;

   // First check all inlining restrictions which are required for correctness

   if ( callee_method->is_abstract()) {

     fail_msg = "abstract method"; // // note: we allow ik->is_abstract()

   } else if (!callee_method->holder()->is_initialized()) {

     fail_msg = "method holder not initialized";

   } else if ( callee_method->is_native()) {

     fail_msg = "native method";

   } else if ( callee_method->dont_inline()) {

     fail_msg = "don't inline by annotation";

   }

   if (!UseOldInlining) {

     if (fail_msg != NULL) {

       *wci_result = *(WarmCallInfo::always_cold());

       set_msg(fail_msg);

       return true;

     }

     if (callee_method->has_unloaded_classes_in_signature()) {

       wci_result->set_profit(wci_result->profit() * 0.1);

     }

     // don't inline exception code unless the top method belongs to an

     // exception class

     if (callee_method->holder()->is_subclass_of(C->env()->Throwable_klass())) {

       ciMethod* top_method = jvms->caller() != NULL ? jvms->caller()->of_depth(1)->method() : method();

       if (!top_method->holder()->is_subclass_of(C->env()->Throwable_klass())) {

         wci_result->set_profit(wci_result->profit() * 0.1);

       }

     }

     if (callee_method->has_compiled_code() &&

         callee_method->instructions_size() > InlineSmallCode) {

       wci_result->set_profit(wci_result->profit() * 0.1);

       // %%% adjust wci_result->size()?

     }

     return false;

   }

   // one more inlining restriction

   if (fail_msg == NULL && callee_method->has_unloaded_classes_in_signature()) {

     fail_msg = "unloaded signature classes";

   }

   if (fail_msg != NULL) {

     set_msg(fail_msg);

     return true;

   }

   // ignore heuristic controls on inlining

   if (callee_method->should_inline()) {

     set_msg("force inline by CompilerOracle");

     return false;

   }

   if (callee_method->should_not_inline()) {

     set_msg("disallowed by CompilerOracle");

     return true;

   }

 #ifndef PRODUCT

   if (ciReplay::should_not_inline(callee_method)) {

     set_msg("disallowed by ciReplay");

     return true;

   }

 #endif

   // Now perform checks which are heuristic

   if (is_unboxing_method(callee_method, C)) {

     // Inline unboxing methods.

     return false;

   }

   if (!callee_method->force_inline()) {

     if (callee_method->has_compiled_code() &&

         callee_method->instructions_size() > InlineSmallCode) {

       set_msg("already compiled into a big method");

       return true;

     }

   }

   // don't inline exception code unless the top method belongs to an

   // exception class

   if (caller_tree() != NULL &&

       callee_method->holder()->is_subclass_of(C->env()->Throwable_klass())) {

     const InlineTree *top = this;

     while (top->caller_tree() != NULL) top = top->caller_tree();

     ciInstanceKlass* k = top->method()->holder();

     if (!k->is_subclass_of(C->env()->Throwable_klass())) {

       set_msg("exception method");

       return true;

     }

   }

   // use frequency-based objections only for non-trivial methods

   if (callee_method->code_size() <= MaxTrivialSize) {

     return false;

   }

   // don't use counts with -Xcomp or CTW

   if (UseInterpreter && !CompileTheWorld) {

     if (!callee_method->has_compiled_code() &&

         !callee_method->was_executed_more_than(0)) {

       set_msg("never executed");

       return true;

     }

     if (is_init_with_ea(callee_method, caller_method, C)) {

       // Escape Analysis: inline all executed constructors

       return false;

     } else if (!callee_method->was_executed_more_than(MIN2(MinInliningThreshold,

                                                            CompileThreshold >> 1))) {

       set_msg("executed < MinInliningThreshold times");

       return true;

     }

   }

   return false;

 }

 //-----------------------------try_to_inline-----------------------------------

 // return true if ok

 // Relocated from "InliningClosure::try_to_inline"

 bool InlineTree::try_to_inline(ciMethod* callee_method, ciMethod* caller_method,

                                int caller_bci, JVMState* jvms, ciCallProfile& profile,

                                WarmCallInfo* wci_result, bool& should_delay) {

    // Old algorithm had funny accumulating BC-size counters

   if (UseOldInlining && ClipInlining

       && (int)count_inline_bcs() >= DesiredMethodLimit) {

     if (!callee_method->force_inline() || !IncrementalInline) {

       set_msg("size > DesiredMethodLimit");

       return false;

     } else if (!C->inlining_incrementally()) {

       should_delay = true;

     }

   }

   if (!should_inline(callee_method, caller_method, caller_bci, profile,

                      wci_result)) {

     return false;

   }

   if (should_not_inline(callee_method, caller_method, jvms, wci_result)) {

     return false;

   }

   if (InlineAccessors && callee_method->is_accessor()) {

     // accessor methods are not subject to any of the following limits.

     set_msg("accessor");

     return true;

   }

   // suppress a few checks for accessors and trivial methods

   if (callee_method->code_size() > MaxTrivialSize) {

     // don't inline into giant methods

     if (C->over_inlining_cutoff()) {

       if ((!callee_method->force_inline() && !caller_method->is_compiled_lambda_form())

           || !IncrementalInline) {

         set_msg("NodeCountInliningCutoff");

         return false;

       } else {

         should_delay = true;

       }

     }

     if ((!UseInterpreter || CompileTheWorld) &&

         is_init_with_ea(callee_method, caller_method, C)) {

       // Escape Analysis stress testing when running Xcomp or CTW:

       // inline constructors even if they are not reached.

     } else if (profile.count() == 0) {

       // don't inline unreached call sites

        set_msg("call site not reached");

        return false;

     }

   }

   if (!C->do_inlining() && InlineAccessors) {

     set_msg("not an accessor");

     return false;

   }

   if (inline_level() > _max_inline_level) {

     if (callee_method->force_inline() && inline_level() > MaxForceInlineLevel) {

       set_msg("MaxForceInlineLevel");

       return false;

     }

     if (!callee_method->force_inline() || !IncrementalInline) {

       set_msg("inlining too deep");

       return false;

     } else if (!C->inlining_incrementally()) {

       should_delay = true;

     }

   }

   // detect direct and indirect recursive inlining

   {

     // count the current method and the callee

     const bool is_compiled_lambda_form = callee_method->is_compiled_lambda_form();

     int inline_level = 0;

     if (!is_compiled_lambda_form) {

       if (method() == callee_method) {

         inline_level++;

       }

     }

     // count callers of current method and callee

     Node* callee_argument0 = is_compiled_lambda_form ? jvms->map()->argument(jvms, 0)->uncast() : NULL;

     for (JVMState* j = jvms->caller(); j != NULL && j->has_method(); j = j->caller()) {

       if (j->method() == callee_method) {

         if (is_compiled_lambda_form) {

           // Since compiled lambda forms are heavily reused we allow recursive inlining.  If it is truly

           // a recursion (using the same "receiver") we limit inlining otherwise we can easily blow the

           // compiler stack.

           Node* caller_argument0 = j->map()->argument(j, 0)->uncast();

           if (caller_argument0 == callee_argument0) {

             inline_level++;

           }

         } else {

           inline_level++;

         }

       }

     }

     if (inline_level > MaxRecursiveInlineLevel) {

       set_msg("recursive inlining is too deep");

       return false;

     }

   }

   int size = callee_method->code_size_for_inlining();

   if (UseOldInlining && ClipInlining

       && (int)count_inline_bcs() + size >= DesiredMethodLimit) {

     if (!callee_method->force_inline() || !IncrementalInline) {

       set_msg("size > DesiredMethodLimit");

       return false;

     } else if (!C->inlining_incrementally()) {

       should_delay = true;

     }

   }

   // ok, inline this method

   return true;

 }

 //------------------------------pass_initial_checks----------------------------

 bool pass_initial_checks(ciMethod* caller_method, int caller_bci, ciMethod* callee_method) {

   ciInstanceKlass *callee_holder = callee_method ? callee_method->holder() : NULL;

   // Check if a callee_method was suggested

   if( callee_method == NULL )            return false;

   // Check if klass of callee_method is loaded

   if( !callee_holder->is_loaded() )      return false;

   if( !callee_holder->is_initialized() ) return false;

   if( !UseInterpreter || CompileTheWorld /* running Xcomp or CTW */ ) {

     // Checks that constant pool's call site has been visited

     // stricter than callee_holder->is_initialized()

     ciBytecodeStream iter(caller_method);

     iter.force_bci(caller_bci);

     Bytecodes::Code call_bc = iter.cur_bc();

     // An invokedynamic instruction does not have a klass.

     if (call_bc != Bytecodes::_invokedynamic) {

       int index = iter.get_index_u2_cpcache();

       if (!caller_method->is_klass_loaded(index, true)) {

         return false;

       }

       // Try to do constant pool resolution if running Xcomp

       if( !caller_method->check_call(index, call_bc == Bytecodes::_invokestatic) ) {

         return false;

       }

     }

   }

   // We will attempt to see if a class/field/etc got properly loaded.  If it

   // did not, it may attempt to throw an exception during our probing.  Catch

   // and ignore such exceptions and do not attempt to compile the method.

   if( callee_method->should_exclude() )  return false;

   return true;

 }

 //------------------------------check_can_parse--------------------------------

 const char* InlineTree::check_can_parse(ciMethod* callee) {

   // Certain methods cannot be parsed at all:

   if ( callee->is_native())                     return "native method";

   if ( callee->is_abstract())                   return "abstract method";

   if (!callee->can_be_compiled())               return "not compilable (disabled)";

   if (!callee->has_balanced_monitors())         return "not compilable (unbalanced monitors)";

   if ( callee->get_flow_analysis()->failing())  return "not compilable (flow analysis failed)";

   return NULL;

 }

 //------------------------------print_inlining---------------------------------

 void InlineTree::print_inlining(ciMethod* callee_method, int caller_bci,

                                 bool success) const {

   const char* inline_msg = msg();

   assert(inline_msg != NULL, "just checking");

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

     if (success) {

       C->log()->inline_success(inline_msg);

     } else {

       C->log()->inline_fail(inline_msg);

     }

   }

   if (C->print_inlining()) {

     C->print_inlining(callee_method, inline_level(), caller_bci, inline_msg);

     if (callee_method == NULL) tty->print(" callee not monotonic or profiled");

     if (Verbose && callee_method) {

       const InlineTree *top = this;

       while( top->caller_tree() != NULL ) { top = top->caller_tree(); }

       //tty->print("  bcs: %d+%d  invoked: %d", top->count_inline_bcs(), callee_method->code_size(), callee_method->interpreter_invocation_count());

     }

   }

 }

 //------------------------------ok_to_inline-----------------------------------

 WarmCallInfo* InlineTree::ok_to_inline(ciMethod* callee_method, JVMState* jvms, ciCallProfile& profile, WarmCallInfo* initial_wci, bool& should_delay) {

   assert(callee_method != NULL, "caller checks for optimized virtual!");

   assert(!should_delay, "should be initialized to false");

 #ifdef ASSERT

   // Make sure the incoming jvms has the same information content as me.

   // This means that we can eventually make this whole class AllStatic.

   if (jvms->caller() == NULL) {

     assert(_caller_jvms == NULL, "redundant instance state");

   } else {

     assert(_caller_jvms->same_calls_as(jvms->caller()), "redundant instance state");

   }

   assert(_method == jvms->method(), "redundant instance state");

 #endif

   int         caller_bci    = jvms->bci();

   ciMethod*   caller_method = jvms->method();

   // Do some initial checks.

   if (!pass_initial_checks(caller_method, caller_bci, callee_method)) {

     set_msg("failed initial checks");

     print_inlining(callee_method, caller_bci, false /* !success */);

     return NULL;

   }

   // Do some parse checks.

   set_msg(check_can_parse(callee_method));

   if (msg() != NULL) {

     print_inlining(callee_method, caller_bci, false /* !success */);

     return NULL;

   }

   // Check if inlining policy says no.

   WarmCallInfo wci = *(initial_wci);

   bool success = try_to_inline(callee_method, caller_method, caller_bci,

                                jvms, profile, &wci, should_delay);

 #ifndef PRODUCT

   if (UseOldInlining && InlineWarmCalls

       && (PrintOpto || C->print_inlining())) {

     bool cold = wci.is_cold();

     bool hot  = !cold && wci.is_hot();

     bool old_cold = !success;

     if (old_cold != cold || (Verbose || WizardMode)) {

       if (msg() == NULL) {

         set_msg("OK");

       }

       tty->print("   OldInlining= %4s : %s\n           WCI=",

                  old_cold ? "cold" : "hot", msg());

       wci.print();

     }

   }

 #endif

   if (UseOldInlining) {

     if (success) {

       wci = *(WarmCallInfo::always_hot());

     } else {

       wci = *(WarmCallInfo::always_cold());

     }

   }

   if (!InlineWarmCalls) {

     if (!wci.is_cold() && !wci.is_hot()) {

       // Do not inline the warm calls.

       wci = *(WarmCallInfo::always_cold());

     }

   }

   if (!wci.is_cold()) {

     // Inline!

     if (msg() == NULL) {

       set_msg("inline (hot)");

     }

     print_inlining(callee_method, caller_bci, true /* success */);

     if (UseOldInlining)

       build_inline_tree_for_callee(callee_method, jvms, caller_bci);

     if (InlineWarmCalls && !wci.is_hot())

       return new (C) WarmCallInfo(wci);  // copy to heap

     return WarmCallInfo::always_hot();

   }

   // Do not inline

   if (msg() == NULL) {

     set_msg("too cold to inline");

   }

   print_inlining(callee_method, caller_bci, false /* !success */ );

   return NULL;

 }

 //------------------------------compute_callee_frequency-----------------------

 float InlineTree::compute_callee_frequency( int caller_bci ) const {

   int count  = method()->interpreter_call_site_count(caller_bci);

   int invcnt = method()->interpreter_invocation_count();

   float freq = (float)count/(float)invcnt;

   // Call-site count / interpreter invocation count, scaled recursively.

   // Always between 0.0 and 1.0.  Represents the percentage of the method's

   // total execution time used at this call site.

   return freq;

 }

 //------------------------------build_inline_tree_for_callee-------------------

 InlineTree *InlineTree::build_inline_tree_for_callee( ciMethod* callee_method, JVMState* caller_jvms, int caller_bci) {

   float recur_frequency = _site_invoke_ratio * compute_callee_frequency(caller_bci);

   // Attempt inlining.

   InlineTree* old_ilt = callee_at(caller_bci, callee_method);

   if (old_ilt != NULL) {

     return old_ilt;

   }

   int max_inline_level_adjust = 0;

   if (caller_jvms->method() != NULL) {

     if (caller_jvms->method()->is_compiled_lambda_form())

       max_inline_level_adjust += 1;  // don't count actions in MH or indy adapter frames

     else if (callee_method->is_method_handle_intrinsic() ||

              callee_method->is_compiled_lambda_form()) {

       max_inline_level_adjust += 1;  // don't count method handle calls from java.lang.invoke implem

     }

     if (max_inline_level_adjust != 0 && C->print_inlining() && (Verbose || WizardMode)) {

       CompileTask::print_inline_indent(inline_level());

       tty->print_cr(" \\-> discounting inline depth");

     }

     if (max_inline_level_adjust != 0 && C->log()) {

       int id1 = C->log()->identify(caller_jvms->method());

       int id2 = C->log()->identify(callee_method);

       C->log()->elem("inline_level_discount caller='%d' callee='%d'", id1, id2);

     }

   }

   InlineTree* ilt = new InlineTree(C, this, callee_method, caller_jvms, caller_bci, recur_frequency, _max_inline_level + max_inline_level_adjust);

   _subtrees.append(ilt);

   NOT_PRODUCT( _count_inlines += 1; )

   return ilt;

 }

 //---------------------------------------callee_at-----------------------------

 InlineTree *InlineTree::callee_at(int bci, ciMethod* callee) const {

   for (int i = 0; i < _subtrees.length(); i++) {

     InlineTree* sub = _subtrees.at(i);

     if (sub->caller_bci() == bci && callee == sub->method()) {

       return sub;

     }

   }

   return NULL;

 }

 //------------------------------build_inline_tree_root-------------------------

 InlineTree *InlineTree::build_inline_tree_root() {

   Compile* C = Compile::current();

   // Root of inline tree

   InlineTree* ilt = new InlineTree(C, NULL, C->method(), NULL, -1, 1.0F, MaxInlineLevel);

   return ilt;

 }

 //-------------------------find_subtree_from_root-----------------------------

 // Given a jvms, which determines a call chain from the root method,

 // find the corresponding inline tree.

 // Note: This method will be removed or replaced as InlineTree goes away.

 InlineTree* InlineTree::find_subtree_from_root(InlineTree* root, JVMState* jvms, ciMethod* callee) {

   InlineTree* iltp = root;

   uint depth = jvms && jvms->has_method() ? jvms->depth() : 0;

   for (uint d = 1; d <= depth; d++) {

     JVMState* jvmsp  = jvms->of_depth(d);

     // Select the corresponding subtree for this bci.

     assert(jvmsp->method() == iltp->method(), "tree still in sync");

     ciMethod* d_callee = (d == depth) ? callee : jvms->of_depth(d+1)->method();

     InlineTree* sub = iltp->callee_at(jvmsp->bci(), d_callee);

     if (sub == NULL) {

       if (d == depth) {

         sub = iltp->build_inline_tree_for_callee(d_callee, jvmsp, jvmsp->bci());

       }

       guarantee(sub != NULL, "should be a sub-ilt here");

       return sub;

     }

     iltp = sub;

   }

   return iltp;

 }

 #ifndef PRODUCT

 void InlineTree::print_impl(outputStream* st, int indent) const {

   for (int i = 0; i < indent; i++) st->print(" ");

   st->print(" @ %d ", caller_bci());

   method()->print_short_name(st);

   st->cr();

   for (int i = 0 ; i < _subtrees.length(); i++) {

     _subtrees.at(i)->print_impl(st, indent + 2);

   }

 }

 void InlineTree::print_value_on(outputStream* st) const {

   print_impl(st, 2);

 }

 #endif