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

 /*

  * Copyright 2000-2008 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

  * CA 95054 USA or visit www.sun.com if you need additional information or

  * have any questions.

  *

  */

 #include "incls/_precompiled.incl"

 #include "incls/_callGenerator.cpp.incl"

 CallGenerator::CallGenerator(ciMethod* method) {

   _method = method;

 }

 // Utility function.

 const TypeFunc* CallGenerator::tf() const {

   return TypeFunc::make(method());

 }

 //-----------------------------ParseGenerator---------------------------------

 // Internal class which handles all direct bytecode traversal.

 class ParseGenerator : public InlineCallGenerator {

 private:

   bool  _is_osr;

   float _expected_uses;

 public:

   ParseGenerator(ciMethod* method, float expected_uses, bool is_osr = false)

     : InlineCallGenerator(method)

   {

     _is_osr        = is_osr;

     _expected_uses = expected_uses;

     assert(can_parse(method, is_osr), "parse must be possible");

   }

   // Can we build either an OSR or a regular parser for this method?

   static bool can_parse(ciMethod* method, int is_osr = false);

   virtual bool      is_parse() const           { return true; }

   virtual JVMState* generate(JVMState* jvms);

   int is_osr() { return _is_osr; }

 };

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

   Compile* C = Compile::current();

   if (is_osr()) {

     // The JVMS for a OSR has a single argument (see its TypeFunc).

     assert(jvms->depth() == 1, "no inline OSR");

   }

   if (C->failing()) {

     return NULL;  // bailing out of the compile; do not try to parse

   }

   Parse parser(jvms, method(), _expected_uses);

   // Grab signature for matching/allocation

 #ifdef ASSERT

   if (parser.tf() != (parser.depth() == 1 ? 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");

   }

 #endif

   GraphKit& exits = parser.exits();

   if (C->failing()) {

     while (exits.pop_exception_state() != NULL) ;

     return NULL;

   }

   assert(exits.jvms()->same_calls_as(jvms), "sanity");

   // Simply return the exit state of the parser,

   // augmented by any exceptional states.

   return exits.transfer_exceptions_into_jvms();

 }

 //---------------------------DirectCallGenerator------------------------------

 // Internal class which handles all out-of-line calls w/o receiver type checks.

 class DirectCallGenerator : public CallGenerator {

 public:

   DirectCallGenerator(ciMethod* method)

     : CallGenerator(method)

   {

   }

   virtual JVMState* generate(JVMState* jvms);

 };

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

   GraphKit kit(jvms);

   bool is_static = method()->is_static();

   address target = is_static ? SharedRuntime::get_resolve_static_call_stub()

                              : SharedRuntime::get_resolve_opt_virtual_call_stub();

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

     kit.C->log()->elem("direct_call bci='%d'", jvms->bci());

   }

   CallStaticJavaNode *call = new (kit.C, tf()->domain()->cnt()) CallStaticJavaNode(tf(), target, method(), kit.bci());

   if (!is_static) {

     // Make an explicit receiver null_check as part of this call.

     // Since we share a map with the caller, his JVMS gets adjusted.

     kit.null_check_receiver(method());

     if (kit.stopped()) {

       // And dump it back to the caller, decorated with any exceptions:

       return kit.transfer_exceptions_into_jvms();

     }

     // Mark the call node as virtual, sort of:

     call->set_optimized_virtual(true);

   }

   kit.set_arguments_for_java_call(call);

   kit.set_edges_for_java_call(call);

   Node* ret = kit.set_results_for_java_call(call);

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

   return kit.transfer_exceptions_into_jvms();

 }

 class VirtualCallGenerator : public CallGenerator {

 private:

   int _vtable_index;

 public:

   VirtualCallGenerator(ciMethod* method, int vtable_index)

     : CallGenerator(method), _vtable_index(vtable_index)

   {

     assert(vtable_index == methodOopDesc::invalid_vtable_index ||

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

   }

   virtual bool      is_virtual() const          { return true; }

   virtual JVMState* generate(JVMState* jvms);

 };

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

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

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

   GraphKit kit(jvms);

   Node* receiver = kit.argument(0);

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

     kit.C->log()->elem("virtual_call bci='%d'", jvms->bci());

   }

   // If the receiver is a constant null, do not torture the system

   // by attempting to call through it.  The compile will proceed

   // correctly, but may bail out in final_graph_reshaping, because

   // the call instruction will have a seemingly deficient out-count.

   // (The bailout says something misleading about an "infinite loop".)

   if (kit.gvn().type(receiver)->higher_equal(TypePtr::NULL_PTR)) {

     kit.inc_sp(method()->arg_size());  // restore arguments

     kit.uncommon_trap(Deoptimization::Reason_null_check,

                       Deoptimization::Action_none,

                       NULL, "null receiver");

     return kit.transfer_exceptions_into_jvms();

   }

   // Ideally we would unconditionally do a null check here and let it

   // be converted to an implicit check based on profile information.

   // However currently the conversion to implicit null checks in

   // Block::implicit_null_check() only looks for loads and stores, not calls.

   ciMethod *caller = kit.method();

   ciMethodData *caller_md = (caller == NULL) ? NULL : caller->method_data();

   if (!UseInlineCaches || !ImplicitNullChecks ||

        ((ImplicitNullCheckThreshold > 0) && caller_md &&

        (caller_md->trap_count(Deoptimization::Reason_null_check)

        >= (uint)ImplicitNullCheckThreshold))) {

     // Make an explicit receiver null_check as part of this call.

     // Since we share a map with the caller, his JVMS gets adjusted.

     receiver = kit.null_check_receiver(method());

     if (kit.stopped()) {

       // And dump it back to the caller, decorated with any exceptions:

       return kit.transfer_exceptions_into_jvms();

     }

   }

   assert(!method()->is_static(), "virtual call must not be to static");

   assert(!method()->is_final(), "virtual call should not be to final");

   assert(!method()->is_private(), "virtual call should not be to private");

   assert(_vtable_index == methodOopDesc::invalid_vtable_index || !UseInlineCaches,

          "no vtable calls if +UseInlineCaches ");

   address target = SharedRuntime::get_resolve_virtual_call_stub();

   // Normal inline cache used for call

   CallDynamicJavaNode *call = new (kit.C, tf()->domain()->cnt()) CallDynamicJavaNode(tf(), target, method(), _vtable_index, kit.bci());

   kit.set_arguments_for_java_call(call);

   kit.set_edges_for_java_call(call);

   Node* ret = kit.set_results_for_java_call(call);

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

   // Represent the effect of an implicit receiver null_check

   // as part of this call.  Since we share a map with the caller,

   // his JVMS gets adjusted.

   kit.cast_not_null(receiver);

   return kit.transfer_exceptions_into_jvms();

 }

 bool ParseGenerator::can_parse(ciMethod* m, int entry_bci) {

   // Certain methods cannot be parsed at all:

   if (!m->can_be_compiled())              return false;

   if (!m->has_balanced_monitors())        return false;

   if (m->get_flow_analysis()->failing())  return false;

   // (Methods may bail out for other reasons, after the parser is run.

   // We try to avoid this, but if forced, we must return (Node*)NULL.

   // The user of the CallGenerator must check for this condition.)

   return true;

 }

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

   if (!ParseGenerator::can_parse(m))  return NULL;

   return new ParseGenerator(m, expected_uses);

 }

 // As a special case, the JVMS passed to this CallGenerator is

 // for the method execution already in progress, not just the JVMS

 // of the caller.  Thus, this CallGenerator cannot be mixed with others!

 CallGenerator* CallGenerator::for_osr(ciMethod* m, int osr_bci) {

   if (!ParseGenerator::can_parse(m, true))  return NULL;

   float past_uses = m->interpreter_invocation_count();

   float expected_uses = past_uses;

   return new ParseGenerator(m, expected_uses, true);

 }

 CallGenerator* CallGenerator::for_direct_call(ciMethod* m) {

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

   return new DirectCallGenerator(m);

 }

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

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

   return new VirtualCallGenerator(m, vtable_index);

 }

 //---------------------------WarmCallGenerator--------------------------------

 // Internal class which handles initial deferral of inlining decisions.

 class WarmCallGenerator : public CallGenerator {

   WarmCallInfo*   _call_info;

   CallGenerator*  _if_cold;

   CallGenerator*  _if_hot;

   bool            _is_virtual;   // caches virtuality of if_cold

   bool            _is_inline;    // caches inline-ness of if_hot

 public:

   WarmCallGenerator(WarmCallInfo* ci,

                     CallGenerator* if_cold,

                     CallGenerator* if_hot)

     : CallGenerator(if_cold->method())

   {

     assert(method() == if_hot->method(), "consistent choices");

     _call_info  = ci;

     _if_cold    = if_cold;

     _if_hot     = if_hot;

     _is_virtual = if_cold->is_virtual();

     _is_inline  = if_hot->is_inline();

   }

   virtual bool      is_inline() const           { return _is_inline; }

   virtual bool      is_virtual() const          { return _is_virtual; }

   virtual bool      is_deferred() const         { return true; }

   virtual JVMState* generate(JVMState* jvms);

 };

 CallGenerator* CallGenerator::for_warm_call(WarmCallInfo* ci,

                                             CallGenerator* if_cold,

                                             CallGenerator* if_hot) {

   return new WarmCallGenerator(ci, if_cold, if_hot);

 }

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

   Compile* C = Compile::current();

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

     C->log()->elem("warm_call bci='%d'", jvms->bci());

   }

   jvms = _if_cold->generate(jvms);

   if (jvms != NULL) {

     Node* m = jvms->map()->control();

     if (m->is_CatchProj()) m = m->in(0);  else m = C->top();

     if (m->is_Catch())     m = m->in(0);  else m = C->top();

     if (m->is_Proj())      m = m->in(0);  else m = C->top();

     if (m->is_CallJava()) {

       _call_info->set_call(m->as_Call());

       _call_info->set_hot_cg(_if_hot);

 #ifndef PRODUCT

       if (PrintOpto || PrintOptoInlining) {

         tty->print_cr("Queueing for warm inlining at bci %d:", jvms->bci());

         tty->print("WCI: ");

         _call_info->print();

       }

 #endif

       _call_info->set_heat(_call_info->compute_heat());

       C->set_warm_calls(_call_info->insert_into(C->warm_calls()));

     }

   }

   return jvms;

 }

 void WarmCallInfo::make_hot() {

   Compile* C = Compile::current();

   // Replace the callnode with something better.

   CallJavaNode* call = this->call()->as_CallJava();

   ciMethod* method   = call->method();

   int       nargs    = method->arg_size();

   JVMState* jvms     = call->jvms()->clone_shallow(C);

   uint size = TypeFunc::Parms + MAX2(2, nargs);

   SafePointNode* map = new (C, size) SafePointNode(size, jvms);

   for (uint i1 = 0; i1 < (uint)(TypeFunc::Parms + nargs); i1++) {

     map->init_req(i1, call->in(i1));

   }

   jvms->set_map(map);

   jvms->set_offsets(map->req());

   jvms->set_locoff(TypeFunc::Parms);

   jvms->set_stkoff(TypeFunc::Parms);

   GraphKit kit(jvms);

   JVMState* new_jvms = _hot_cg->generate(kit.jvms());

   if (new_jvms == NULL)  return;  // no change

   if (C->failing())      return;

   kit.set_jvms(new_jvms);

   Node* res = C->top();

   int   res_size = method->return_type()->size();

   if (res_size != 0) {

     kit.inc_sp(-res_size);

     res = kit.argument(0);

   }

   GraphKit ekit(kit.combine_and_pop_all_exception_states()->jvms());

   // Replace the call:

   for (DUIterator i = call->outs(); call->has_out(i); i++) {

     Node* n = call->out(i);

     Node* nn = NULL;  // replacement

     if (n->is_Proj()) {

       ProjNode* nproj = n->as_Proj();

       assert(nproj->_con < (uint)(TypeFunc::Parms + (res_size ? 1 : 0)), "sane proj");

       if (nproj->_con == TypeFunc::Parms) {

         nn = res;

       } else {

         nn = kit.map()->in(nproj->_con);

       }

       if (nproj->_con == TypeFunc::I_O) {

         for (DUIterator j = nproj->outs(); nproj->has_out(j); j++) {

           Node* e = nproj->out(j);

           if (e->Opcode() == Op_CreateEx) {

             e->replace_by(ekit.argument(0));

           } else if (e->Opcode() == Op_Catch) {

             for (DUIterator k = e->outs(); e->has_out(k); k++) {

               CatchProjNode* p = e->out(j)->as_CatchProj();

               if (p->is_handler_proj()) {

                 p->replace_by(ekit.control());

               } else {

                 p->replace_by(kit.control());

               }

             }

           }

         }

       }

     }

     NOT_PRODUCT(if (!nn)  n->dump(2));

     assert(nn != NULL, "don't know what to do with this user");

     n->replace_by(nn);

   }

 }

 void WarmCallInfo::make_cold() {

   // No action:  Just dequeue.

 }

 //------------------------PredictedCallGenerator------------------------------

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

 class PredictedCallGenerator : public CallGenerator {

   ciKlass*       _predicted_receiver;

   CallGenerator* _if_missed;

   CallGenerator* _if_hit;

   float          _hit_prob;

 public:

   PredictedCallGenerator(ciKlass* predicted_receiver,

                          CallGenerator* if_missed,

                          CallGenerator* if_hit, float hit_prob)

     : CallGenerator(if_missed->method())

   {

     // The call profile data may predict the hit_prob as extreme as 0 or 1.

     // Remove the extremes values from the range.

     if (hit_prob > PROB_MAX)   hit_prob = PROB_MAX;

     if (hit_prob < PROB_MIN)   hit_prob = PROB_MIN;

     _predicted_receiver = predicted_receiver;

     _if_missed          = if_missed;

     _if_hit             = if_hit;

     _hit_prob           = hit_prob;

   }

   virtual bool      is_virtual()   const    { return true; }

   virtual bool      is_inline()    const    { return _if_hit->is_inline(); }

   virtual bool      is_deferred()  const    { return _if_hit->is_deferred(); }

   virtual JVMState* generate(JVMState* jvms);

 };

 CallGenerator* CallGenerator::for_predicted_call(ciKlass* predicted_receiver,

                                                  CallGenerator* if_missed,

                                                  CallGenerator* if_hit,

                                                  float hit_prob) {

   return new PredictedCallGenerator(predicted_receiver, if_missed, if_hit, hit_prob);

 }

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

   GraphKit kit(jvms);

   PhaseGVN& gvn = kit.gvn();

   // We need an explicit receiver null_check before checking its type.

   // We share a map with the caller, so his JVMS gets adjusted.

   Node* receiver = kit.argument(0);

   CompileLog* log = kit.C->log();

   if (log != NULL) {

     log->elem("predicted_call bci='%d' klass='%d'",

               jvms->bci(), log->identify(_predicted_receiver));

   }

   receiver = kit.null_check_receiver(method());

   if (kit.stopped()) {

     return kit.transfer_exceptions_into_jvms();

   }

   Node* exact_receiver = receiver;  // will get updated in place...

   Node* slow_ctl = kit.type_check_receiver(receiver,

                                            _predicted_receiver, _hit_prob,

                                            &exact_receiver);

   SafePointNode* slow_map = NULL;

   JVMState* slow_jvms;

   { PreserveJVMState pjvms(&kit);

     kit.set_control(slow_ctl);

     if (!kit.stopped()) {

       slow_jvms = _if_missed->generate(kit.sync_jvms());

       assert(slow_jvms != NULL, "miss path must not fail to generate");

       kit.add_exception_states_from(slow_jvms);

       kit.set_map(slow_jvms->map());

       if (!kit.stopped())

         slow_map = kit.stop();

     }

   }

   if (kit.stopped()) {

     // Instance exactly does not matches the desired type.

     kit.set_jvms(slow_jvms);

     return kit.transfer_exceptions_into_jvms();

   }

   // fall through if the instance exactly matches the desired type

   kit.replace_in_map(receiver, exact_receiver);

   // Make the hot call:

   JVMState* new_jvms = _if_hit->generate(kit.sync_jvms());

   if (new_jvms == NULL) {

     // Inline failed, so make a direct call.

     assert(_if_hit->is_inline(), "must have been a failed inline");

     CallGenerator* cg = CallGenerator::for_direct_call(_if_hit->method());

     new_jvms = cg->generate(kit.sync_jvms());

   }

   kit.add_exception_states_from(new_jvms);

   kit.set_jvms(new_jvms);

   // Need to merge slow and fast?

   if (slow_map == NULL) {

     // The fast path is the only path remaining.

     return kit.transfer_exceptions_into_jvms();

   }

   if (kit.stopped()) {

     // Inlined method threw an exception, so it's just the slow path after all.

     kit.set_jvms(slow_jvms);

     return kit.transfer_exceptions_into_jvms();

   }

   // Finish the diamond.

   kit.C->set_has_split_ifs(true); // Has chance for split-if optimization

   RegionNode* region = new (kit.C, 3) RegionNode(3);

   region->init_req(1, kit.control());

   region->init_req(2, slow_map->control());

   kit.set_control(gvn.transform(region));

   Node* iophi = PhiNode::make(region, kit.i_o(), Type::ABIO);

   iophi->set_req(2, slow_map->i_o());

   kit.set_i_o(gvn.transform(iophi));

   kit.merge_memory(slow_map->merged_memory(), region, 2);

   uint tos = kit.jvms()->stkoff() + kit.sp();

   uint limit = slow_map->req();

   for (uint i = TypeFunc::Parms; i < limit; i++) {

     // Skip unused stack slots; fast forward to monoff();

     if (i == tos) {

       i = kit.jvms()->monoff();

       if( i >= limit ) break;

     }

     Node* m = kit.map()->in(i);

     Node* n = slow_map->in(i);

     if (m != n) {

       const Type* t = gvn.type(m)->meet(gvn.type(n));

       Node* phi = PhiNode::make(region, m, t);

       phi->set_req(2, n);

       kit.map()->set_req(i, gvn.transform(phi));

     }

   }

   return kit.transfer_exceptions_into_jvms();

 }

 //-------------------------UncommonTrapCallGenerator-----------------------------

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

 class UncommonTrapCallGenerator : public CallGenerator {

   Deoptimization::DeoptReason _reason;

   Deoptimization::DeoptAction _action;

 public:

   UncommonTrapCallGenerator(ciMethod* m,

                             Deoptimization::DeoptReason reason,

                             Deoptimization::DeoptAction action)

     : CallGenerator(m)

   {

     _reason = reason;

     _action = action;

   }

   virtual bool      is_virtual() const          { ShouldNotReachHere(); return false; }

   virtual bool      is_trap() const             { return true; }

   virtual JVMState* generate(JVMState* jvms);

 };

 CallGenerator*

 CallGenerator::for_uncommon_trap(ciMethod* m,

                                  Deoptimization::DeoptReason reason,

                                  Deoptimization::DeoptAction action) {

   return new UncommonTrapCallGenerator(m, reason, action);

 }

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

   GraphKit kit(jvms);

   // Take the trap with arguments pushed on the stack.  (Cf. null_check_receiver).

   int nargs = method()->arg_size();

   kit.inc_sp(nargs);

   assert(nargs <= kit.sp() && kit.sp() <= jvms->stk_size(), "sane sp w/ args pushed");

   if (_reason == Deoptimization::Reason_class_check &&

       _action == Deoptimization::Action_maybe_recompile) {

     // Temp fix for 6529811

     // Don't allow uncommon_trap to override our decision to recompile in the event

     // of a class cast failure for a monomorphic call as it will never let us convert

     // the call to either bi-morphic or megamorphic and can lead to unc-trap loops

     bool keep_exact_action = true;

     kit.uncommon_trap(_reason, _action, NULL, "monomorphic vcall checkcast", false, keep_exact_action);

   } else {

     kit.uncommon_trap(_reason, _action);

   }

   return kit.transfer_exceptions_into_jvms();

 }

 // (Note:  Moved hook_up_call to GraphKit::set_edges_for_java_call.)

 // (Node:  Merged hook_up_exits into ParseGenerator::generate.)

 #define NODES_OVERHEAD_PER_METHOD (30.0)

 #define NODES_PER_BYTECODE (9.5)

 void WarmCallInfo::init(JVMState* call_site, ciMethod* call_method, ciCallProfile& profile, float prof_factor) {

   int call_count = profile.count();

   int code_size = call_method->code_size();

   // Expected execution count is based on the historical count:

   _count = call_count < 0 ? 1 : call_site->method()->scale_count(call_count, prof_factor);

   // Expected profit from inlining, in units of simple call-overheads.

   _profit = 1.0;

   // Expected work performed by the call in units of call-overheads.

   // %%% need an empirical curve fit for "work" (time in call)

   float bytecodes_per_call = 3;

   _work = 1.0 + code_size / bytecodes_per_call;

   // Expected size of compilation graph:

   // -XX:+PrintParseStatistics once reported:

   //  Methods seen: 9184  Methods parsed: 9184  Nodes created: 1582391

   //  Histogram of 144298 parsed bytecodes:

   // %%% Need an better predictor for graph size.

   _size = NODES_OVERHEAD_PER_METHOD + (NODES_PER_BYTECODE * code_size);

 }

 // is_cold:  Return true if the node should never be inlined.

 // This is true if any of the key metrics are extreme.

 bool WarmCallInfo::is_cold() const {

   if (count()  <  WarmCallMinCount)        return true;

   if (profit() <  WarmCallMinProfit)       return true;

   if (work()   >  WarmCallMaxWork)         return true;

   if (size()   >  WarmCallMaxSize)         return true;

   return false;

 }

 // is_hot:  Return true if the node should be inlined immediately.

 // This is true if any of the key metrics are extreme.

 bool WarmCallInfo::is_hot() const {

   assert(!is_cold(), "eliminate is_cold cases before testing is_hot");

   if (count()  >= HotCallCountThreshold)   return true;

   if (profit() >= HotCallProfitThreshold)  return true;

   if (work()   <= HotCallTrivialWork)      return true;

   if (size()   <= HotCallTrivialSize)      return true;

   return false;

 }

 // compute_heat:

 float WarmCallInfo::compute_heat() const {

   assert(!is_cold(), "compute heat only on warm nodes");

   assert(!is_hot(),  "compute heat only on warm nodes");

   int min_size = MAX2(0,   (int)HotCallTrivialSize);

   int max_size = MIN2(500, (int)WarmCallMaxSize);

   float method_size = (size() - min_size) / MAX2(1, max_size - min_size);

   float size_factor;

   if      (method_size < 0.05)  size_factor = 4;   // 2 sigmas better than avg.

   else if (method_size < 0.15)  size_factor = 2;   // 1 sigma better than avg.

   else if (method_size < 0.5)   size_factor = 1;   // better than avg.

   else                          size_factor = 0.5; // worse than avg.

   return (count() * profit() * size_factor);

 }

 bool WarmCallInfo::warmer_than(WarmCallInfo* that) {

   assert(this != that, "compare only different WCIs");

   assert(this->heat() != 0 && that->heat() != 0, "call compute_heat 1st");

   if (this->heat() > that->heat())   return true;

   if (this->heat() < that->heat())   return false;

   assert(this->heat() == that->heat(), "no NaN heat allowed");

   // Equal heat.  Break the tie some other way.

   if (!this->call() || !that->call())  return (address)this > (address)that;

   return this->call()->_idx > that->call()->_idx;

 }

 //#define UNINIT_NEXT ((WarmCallInfo*)badAddress)

 #define UNINIT_NEXT ((WarmCallInfo*)NULL)

 WarmCallInfo* WarmCallInfo::insert_into(WarmCallInfo* head) {

   assert(next() == UNINIT_NEXT, "not yet on any list");

   WarmCallInfo* prev_p = NULL;

   WarmCallInfo* next_p = head;

   while (next_p != NULL && next_p->warmer_than(this)) {

     prev_p = next_p;

     next_p = prev_p->next();

   }

   // Install this between prev_p and next_p.

   this->set_next(next_p);

   if (prev_p == NULL)

     head = this;

   else

     prev_p->set_next(this);

   return head;

 }

 WarmCallInfo* WarmCallInfo::remove_from(WarmCallInfo* head) {

   WarmCallInfo* prev_p = NULL;

   WarmCallInfo* next_p = head;

   while (next_p != this) {

     assert(next_p != NULL, "this must be in the list somewhere");

     prev_p = next_p;

     next_p = prev_p->next();

   }

   next_p = this->next();

   debug_only(this->set_next(UNINIT_NEXT));

   // Remove this from between prev_p and next_p.

   if (prev_p == NULL)

     head = next_p;

   else

     prev_p->set_next(next_p);

   return head;

 }

 WarmCallInfo* WarmCallInfo::_always_hot  = NULL;

 WarmCallInfo* WarmCallInfo::_always_cold = NULL;

 WarmCallInfo* WarmCallInfo::always_hot() {

   if (_always_hot == NULL) {

     static double bits[sizeof(WarmCallInfo) / sizeof(double) + 1] = {0};

     WarmCallInfo* ci = (WarmCallInfo*) bits;

     ci->_profit = ci->_count = MAX_VALUE();

     ci->_work   = ci->_size  = MIN_VALUE();

     _always_hot = ci;

   }

   assert(_always_hot->is_hot(), "must always be hot");

   return _always_hot;

 }

 WarmCallInfo* WarmCallInfo::always_cold() {

   if (_always_cold == NULL) {

     static double bits[sizeof(WarmCallInfo) / sizeof(double) + 1] = {0};

     WarmCallInfo* ci = (WarmCallInfo*) bits;

     ci->_profit = ci->_count = MIN_VALUE();

     ci->_work   = ci->_size  = MAX_VALUE();

     _always_cold = ci;

   }

   assert(_always_cold->is_cold(), "must always be cold");

   return _always_cold;

 }

 #ifndef PRODUCT

 void WarmCallInfo::print() const {

   tty->print("%s : C=%6.1f P=%6.1f W=%6.1f S=%6.1f H=%6.1f -> %p",

              is_cold() ? "cold" : is_hot() ? "hot " : "warm",

              count(), profit(), work(), size(), compute_heat(), next());

   tty->cr();

   if (call() != NULL)  call()->dump();

 }

 void print_wci(WarmCallInfo* ci) {

   ci->print();

 }

 void WarmCallInfo::print_all() const {

   for (const WarmCallInfo* p = this; p != NULL; p = p->next())

     p->print();

 }

 int WarmCallInfo::count_all() const {

   int cnt = 0;

   for (const WarmCallInfo* p = this; p != NULL; p = p->next())

     cnt++;

   return cnt;

 }

 #endif //PRODUCT