1 /*
   2  * Copyright 2001-2009 Sun Microsystems, Inc.  All Rights Reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 #include "incls/_precompiled.incl"
  26 #include "incls/_graphKit.cpp.incl"
  27 
  28 //----------------------------GraphKit-----------------------------------------
  29 // Main utility constructor.
  30 GraphKit::GraphKit(JVMState* jvms)
  31   : Phase(Phase::Parser),
  32     _env(C->env()),
  33     _gvn(*C->initial_gvn())
  34 {
  35   _exceptions = jvms->map()->next_exception();
  36   if (_exceptions != NULL)  jvms->map()->set_next_exception(NULL);
  37   set_jvms(jvms);
  38 }
  39 
  40 // Private constructor for parser.
  41 GraphKit::GraphKit()
  42   : Phase(Phase::Parser),
  43     _env(C->env()),
  44     _gvn(*C->initial_gvn())
  45 {
  46   _exceptions = NULL;
  47   set_map(NULL);
  48   debug_only(_sp = -99);
  49   debug_only(set_bci(-99));
  50 }
  51 
  52 
  53 
  54 //---------------------------clean_stack---------------------------------------
  55 // Clear away rubbish from the stack area of the JVM state.
  56 // This destroys any arguments that may be waiting on the stack.
  57 void GraphKit::clean_stack(int from_sp) {
  58   SafePointNode* map      = this->map();
  59   JVMState*      jvms     = this->jvms();
  60   int            stk_size = jvms->stk_size();
  61   int            stkoff   = jvms->stkoff();
  62   Node*          top      = this->top();
  63   for (int i = from_sp; i < stk_size; i++) {
  64     if (map->in(stkoff + i) != top) {
  65       map->set_req(stkoff + i, top);
  66     }
  67   }
  68 }
  69 
  70 
  71 //--------------------------------sync_jvms-----------------------------------
  72 // Make sure our current jvms agrees with our parse state.
  73 JVMState* GraphKit::sync_jvms() const {
  74   JVMState* jvms = this->jvms();
  75   jvms->set_bci(bci());       // Record the new bci in the JVMState
  76   jvms->set_sp(sp());         // Record the new sp in the JVMState
  77   assert(jvms_in_sync(), "jvms is now in sync");
  78   return jvms;
  79 }
  80 
  81 #ifdef ASSERT
  82 bool GraphKit::jvms_in_sync() const {
  83   Parse* parse = is_Parse();
  84   if (parse == NULL) {
  85     if (bci() !=      jvms()->bci())          return false;
  86     if (sp()  != (int)jvms()->sp())           return false;
  87     return true;
  88   }
  89   if (jvms()->method() != parse->method())    return false;
  90   if (jvms()->bci()    != parse->bci())       return false;
  91   int jvms_sp = jvms()->sp();
  92   if (jvms_sp          != parse->sp())        return false;
  93   int jvms_depth = jvms()->depth();
  94   if (jvms_depth       != parse->depth())     return false;
  95   return true;
  96 }
  97 
  98 // Local helper checks for special internal merge points
  99 // used to accumulate and merge exception states.
 100 // They are marked by the region's in(0) edge being the map itself.
 101 // Such merge points must never "escape" into the parser at large,
 102 // until they have been handed to gvn.transform.
 103 static bool is_hidden_merge(Node* reg) {
 104   if (reg == NULL)  return false;
 105   if (reg->is_Phi()) {
 106     reg = reg->in(0);
 107     if (reg == NULL)  return false;
 108   }
 109   return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root();
 110 }
 111 
 112 void GraphKit::verify_map() const {
 113   if (map() == NULL)  return;  // null map is OK
 114   assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
 115   assert(!map()->has_exceptions(),    "call add_exception_states_from 1st");
 116   assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
 117 }
 118 
 119 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
 120   assert(ex_map->next_exception() == NULL, "not already part of a chain");
 121   assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
 122 }
 123 #endif
 124 
 125 //---------------------------stop_and_kill_map---------------------------------
 126 // Set _map to NULL, signalling a stop to further bytecode execution.
 127 // First smash the current map's control to a constant, to mark it dead.
 128 void GraphKit::stop_and_kill_map() {
 129   SafePointNode* dead_map = stop();
 130   if (dead_map != NULL) {
 131     dead_map->disconnect_inputs(NULL); // Mark the map as killed.
 132     assert(dead_map->is_killed(), "must be so marked");
 133   }
 134 }
 135 
 136 
 137 //--------------------------------stopped--------------------------------------
 138 // Tell if _map is NULL, or control is top.
 139 bool GraphKit::stopped() {
 140   if (map() == NULL)           return true;
 141   else if (control() == top()) return true;
 142   else                         return false;
 143 }
 144 
 145 
 146 //-----------------------------has_ex_handler----------------------------------
 147 // Tell if this method or any caller method has exception handlers.
 148 bool GraphKit::has_ex_handler() {
 149   for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) {
 150     if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
 151       return true;
 152     }
 153   }
 154   return false;
 155 }
 156 
 157 //------------------------------save_ex_oop------------------------------------
 158 // Save an exception without blowing stack contents or other JVM state.
 159 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
 160   assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
 161   ex_map->add_req(ex_oop);
 162   debug_only(verify_exception_state(ex_map));
 163 }
 164 
 165 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
 166   assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
 167   Node* ex_oop = ex_map->in(ex_map->req()-1);
 168   if (clear_it)  ex_map->del_req(ex_map->req()-1);
 169   return ex_oop;
 170 }
 171 
 172 //-----------------------------saved_ex_oop------------------------------------
 173 // Recover a saved exception from its map.
 174 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
 175   return common_saved_ex_oop(ex_map, false);
 176 }
 177 
 178 //--------------------------clear_saved_ex_oop---------------------------------
 179 // Erase a previously saved exception from its map.
 180 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
 181   return common_saved_ex_oop(ex_map, true);
 182 }
 183 
 184 #ifdef ASSERT
 185 //---------------------------has_saved_ex_oop----------------------------------
 186 // Erase a previously saved exception from its map.
 187 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
 188   return ex_map->req() == ex_map->jvms()->endoff()+1;
 189 }
 190 #endif
 191 
 192 //-------------------------make_exception_state--------------------------------
 193 // Turn the current JVM state into an exception state, appending the ex_oop.
 194 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
 195   sync_jvms();
 196   SafePointNode* ex_map = stop();  // do not manipulate this map any more
 197   set_saved_ex_oop(ex_map, ex_oop);
 198   return ex_map;
 199 }
 200 
 201 
 202 //--------------------------add_exception_state--------------------------------
 203 // Add an exception to my list of exceptions.
 204 void GraphKit::add_exception_state(SafePointNode* ex_map) {
 205   if (ex_map == NULL || ex_map->control() == top()) {
 206     return;
 207   }
 208 #ifdef ASSERT
 209   verify_exception_state(ex_map);
 210   if (has_exceptions()) {
 211     assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
 212   }
 213 #endif
 214 
 215   // If there is already an exception of exactly this type, merge with it.
 216   // In particular, null-checks and other low-level exceptions common up here.
 217   Node*       ex_oop  = saved_ex_oop(ex_map);
 218   const Type* ex_type = _gvn.type(ex_oop);
 219   if (ex_oop == top()) {
 220     // No action needed.
 221     return;
 222   }
 223   assert(ex_type->isa_instptr(), "exception must be an instance");
 224   for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) {
 225     const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
 226     // We check sp also because call bytecodes can generate exceptions
 227     // both before and after arguments are popped!
 228     if (ex_type2 == ex_type
 229         && e2->_jvms->sp() == ex_map->_jvms->sp()) {
 230       combine_exception_states(ex_map, e2);
 231       return;
 232     }
 233   }
 234 
 235   // No pre-existing exception of the same type.  Chain it on the list.
 236   push_exception_state(ex_map);
 237 }
 238 
 239 //-----------------------add_exception_states_from-----------------------------
 240 void GraphKit::add_exception_states_from(JVMState* jvms) {
 241   SafePointNode* ex_map = jvms->map()->next_exception();
 242   if (ex_map != NULL) {
 243     jvms->map()->set_next_exception(NULL);
 244     for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) {
 245       next_map = ex_map->next_exception();
 246       ex_map->set_next_exception(NULL);
 247       add_exception_state(ex_map);
 248     }
 249   }
 250 }
 251 
 252 //-----------------------transfer_exceptions_into_jvms-------------------------
 253 JVMState* GraphKit::transfer_exceptions_into_jvms() {
 254   if (map() == NULL) {
 255     // We need a JVMS to carry the exceptions, but the map has gone away.
 256     // Create a scratch JVMS, cloned from any of the exception states...
 257     if (has_exceptions()) {
 258       _map = _exceptions;
 259       _map = clone_map();
 260       _map->set_next_exception(NULL);
 261       clear_saved_ex_oop(_map);
 262       debug_only(verify_map());
 263     } else {
 264       // ...or created from scratch
 265       JVMState* jvms = new (C) JVMState(_method, NULL);
 266       jvms->set_bci(_bci);
 267       jvms->set_sp(_sp);
 268       jvms->set_map(new (C, TypeFunc::Parms) SafePointNode(TypeFunc::Parms, jvms));
 269       set_jvms(jvms);
 270       for (uint i = 0; i < map()->req(); i++)  map()->init_req(i, top());
 271       set_all_memory(top());
 272       while (map()->req() < jvms->endoff())  map()->add_req(top());
 273     }
 274     // (This is a kludge, in case you didn't notice.)
 275     set_control(top());
 276   }
 277   JVMState* jvms = sync_jvms();
 278   assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
 279   jvms->map()->set_next_exception(_exceptions);
 280   _exceptions = NULL;   // done with this set of exceptions
 281   return jvms;
 282 }
 283 
 284 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
 285   assert(is_hidden_merge(dstphi), "must be a special merge node");
 286   assert(is_hidden_merge(srcphi), "must be a special merge node");
 287   uint limit = srcphi->req();
 288   for (uint i = PhiNode::Input; i < limit; i++) {
 289     dstphi->add_req(srcphi->in(i));
 290   }
 291 }
 292 static inline void add_one_req(Node* dstphi, Node* src) {
 293   assert(is_hidden_merge(dstphi), "must be a special merge node");
 294   assert(!is_hidden_merge(src), "must not be a special merge node");
 295   dstphi->add_req(src);
 296 }
 297 
 298 //-----------------------combine_exception_states------------------------------
 299 // This helper function combines exception states by building phis on a
 300 // specially marked state-merging region.  These regions and phis are
 301 // untransformed, and can build up gradually.  The region is marked by
 302 // having a control input of its exception map, rather than NULL.  Such
 303 // regions do not appear except in this function, and in use_exception_state.
 304 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
 305   if (failing())  return;  // dying anyway...
 306   JVMState* ex_jvms = ex_map->_jvms;
 307   assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
 308   assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
 309   assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
 310   assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
 311   assert(ex_map->req() == phi_map->req(), "matching maps");
 312   uint tos = ex_jvms->stkoff() + ex_jvms->sp();
 313   Node*         hidden_merge_mark = root();
 314   Node*         region  = phi_map->control();
 315   MergeMemNode* phi_mem = phi_map->merged_memory();
 316   MergeMemNode* ex_mem  = ex_map->merged_memory();
 317   if (region->in(0) != hidden_merge_mark) {
 318     // The control input is not (yet) a specially-marked region in phi_map.
 319     // Make it so, and build some phis.
 320     region = new (C, 2) RegionNode(2);
 321     _gvn.set_type(region, Type::CONTROL);
 322     region->set_req(0, hidden_merge_mark);  // marks an internal ex-state
 323     region->init_req(1, phi_map->control());
 324     phi_map->set_control(region);
 325     Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
 326     record_for_igvn(io_phi);
 327     _gvn.set_type(io_phi, Type::ABIO);
 328     phi_map->set_i_o(io_phi);
 329     for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
 330       Node* m = mms.memory();
 331       Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
 332       record_for_igvn(m_phi);
 333       _gvn.set_type(m_phi, Type::MEMORY);
 334       mms.set_memory(m_phi);
 335     }
 336   }
 337 
 338   // Either or both of phi_map and ex_map might already be converted into phis.
 339   Node* ex_control = ex_map->control();
 340   // if there is special marking on ex_map also, we add multiple edges from src
 341   bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
 342   // how wide was the destination phi_map, originally?
 343   uint orig_width = region->req();
 344 
 345   if (add_multiple) {
 346     add_n_reqs(region, ex_control);
 347     add_n_reqs(phi_map->i_o(), ex_map->i_o());
 348   } else {
 349     // ex_map has no merges, so we just add single edges everywhere
 350     add_one_req(region, ex_control);
 351     add_one_req(phi_map->i_o(), ex_map->i_o());
 352   }
 353   for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
 354     if (mms.is_empty()) {
 355       // get a copy of the base memory, and patch some inputs into it
 356       const TypePtr* adr_type = mms.adr_type(C);
 357       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
 358       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
 359       mms.set_memory(phi);
 360       // Prepare to append interesting stuff onto the newly sliced phi:
 361       while (phi->req() > orig_width)  phi->del_req(phi->req()-1);
 362     }
 363     // Append stuff from ex_map:
 364     if (add_multiple) {
 365       add_n_reqs(mms.memory(), mms.memory2());
 366     } else {
 367       add_one_req(mms.memory(), mms.memory2());
 368     }
 369   }
 370   uint limit = ex_map->req();
 371   for (uint i = TypeFunc::Parms; i < limit; i++) {
 372     // Skip everything in the JVMS after tos.  (The ex_oop follows.)
 373     if (i == tos)  i = ex_jvms->monoff();
 374     Node* src = ex_map->in(i);
 375     Node* dst = phi_map->in(i);
 376     if (src != dst) {
 377       PhiNode* phi;
 378       if (dst->in(0) != region) {
 379         dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
 380         record_for_igvn(phi);
 381         _gvn.set_type(phi, phi->type());
 382         phi_map->set_req(i, dst);
 383         // Prepare to append interesting stuff onto the new phi:
 384         while (dst->req() > orig_width)  dst->del_req(dst->req()-1);
 385       } else {
 386         assert(dst->is_Phi(), "nobody else uses a hidden region");
 387         phi = (PhiNode*)dst;
 388       }
 389       if (add_multiple && src->in(0) == ex_control) {
 390         // Both are phis.
 391         add_n_reqs(dst, src);
 392       } else {
 393         while (dst->req() < region->req())  add_one_req(dst, src);
 394       }
 395       const Type* srctype = _gvn.type(src);
 396       if (phi->type() != srctype) {
 397         const Type* dsttype = phi->type()->meet(srctype);
 398         if (phi->type() != dsttype) {
 399           phi->set_type(dsttype);
 400           _gvn.set_type(phi, dsttype);
 401         }
 402       }
 403     }
 404   }
 405 }
 406 
 407 //--------------------------use_exception_state--------------------------------
 408 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
 409   if (failing()) { stop(); return top(); }
 410   Node* region = phi_map->control();
 411   Node* hidden_merge_mark = root();
 412   assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
 413   Node* ex_oop = clear_saved_ex_oop(phi_map);
 414   if (region->in(0) == hidden_merge_mark) {
 415     // Special marking for internal ex-states.  Process the phis now.
 416     region->set_req(0, region);  // now it's an ordinary region
 417     set_jvms(phi_map->jvms());   // ...so now we can use it as a map
 418     // Note: Setting the jvms also sets the bci and sp.
 419     set_control(_gvn.transform(region));
 420     uint tos = jvms()->stkoff() + sp();
 421     for (uint i = 1; i < tos; i++) {
 422       Node* x = phi_map->in(i);
 423       if (x->in(0) == region) {
 424         assert(x->is_Phi(), "expected a special phi");
 425         phi_map->set_req(i, _gvn.transform(x));
 426       }
 427     }
 428     for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
 429       Node* x = mms.memory();
 430       if (x->in(0) == region) {
 431         assert(x->is_Phi(), "nobody else uses a hidden region");
 432         mms.set_memory(_gvn.transform(x));
 433       }
 434     }
 435     if (ex_oop->in(0) == region) {
 436       assert(ex_oop->is_Phi(), "expected a special phi");
 437       ex_oop = _gvn.transform(ex_oop);
 438     }
 439   } else {
 440     set_jvms(phi_map->jvms());
 441   }
 442 
 443   assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
 444   assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
 445   return ex_oop;
 446 }
 447 
 448 //---------------------------------java_bc-------------------------------------
 449 Bytecodes::Code GraphKit::java_bc() const {
 450   ciMethod* method = this->method();
 451   int       bci    = this->bci();
 452   if (method != NULL && bci != InvocationEntryBci)
 453     return method->java_code_at_bci(bci);
 454   else
 455     return Bytecodes::_illegal;
 456 }
 457 
 458 //------------------------------builtin_throw----------------------------------
 459 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) {
 460   bool must_throw = true;
 461 
 462   if (env()->jvmti_can_post_exceptions()) {
 463     // Do not try anything fancy if we're notifying the VM on every throw.
 464     // Cf. case Bytecodes::_athrow in parse2.cpp.
 465     uncommon_trap(reason, Deoptimization::Action_none,
 466                   (ciKlass*)NULL, (char*)NULL, must_throw);
 467     return;
 468   }
 469 
 470   // If this particular condition has not yet happened at this
 471   // bytecode, then use the uncommon trap mechanism, and allow for
 472   // a future recompilation if several traps occur here.
 473   // If the throw is hot, try to use a more complicated inline mechanism
 474   // which keeps execution inside the compiled code.
 475   bool treat_throw_as_hot = false;
 476   ciMethodData* md = method()->method_data();
 477 
 478   if (ProfileTraps) {
 479     if (too_many_traps(reason)) {
 480       treat_throw_as_hot = true;
 481     }
 482     // (If there is no MDO at all, assume it is early in
 483     // execution, and that any deopts are part of the
 484     // startup transient, and don't need to be remembered.)
 485 
 486     // Also, if there is a local exception handler, treat all throws
 487     // as hot if there has been at least one in this method.
 488     if (C->trap_count(reason) != 0
 489         && method()->method_data()->trap_count(reason) != 0
 490         && has_ex_handler()) {
 491         treat_throw_as_hot = true;
 492     }
 493   }
 494 
 495   // If this throw happens frequently, an uncommon trap might cause
 496   // a performance pothole.  If there is a local exception handler,
 497   // and if this particular bytecode appears to be deoptimizing often,
 498   // let us handle the throw inline, with a preconstructed instance.
 499   // Note:   If the deopt count has blown up, the uncommon trap
 500   // runtime is going to flush this nmethod, not matter what.
 501   if (treat_throw_as_hot
 502       && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) {
 503     // If the throw is local, we use a pre-existing instance and
 504     // punt on the backtrace.  This would lead to a missing backtrace
 505     // (a repeat of 4292742) if the backtrace object is ever asked
 506     // for its backtrace.
 507     // Fixing this remaining case of 4292742 requires some flavor of
 508     // escape analysis.  Leave that for the future.
 509     ciInstance* ex_obj = NULL;
 510     switch (reason) {
 511     case Deoptimization::Reason_null_check:
 512       ex_obj = env()->NullPointerException_instance();
 513       break;
 514     case Deoptimization::Reason_div0_check:
 515       ex_obj = env()->ArithmeticException_instance();
 516       break;
 517     case Deoptimization::Reason_range_check:
 518       ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
 519       break;
 520     case Deoptimization::Reason_class_check:
 521       if (java_bc() == Bytecodes::_aastore) {
 522         ex_obj = env()->ArrayStoreException_instance();
 523       } else {
 524         ex_obj = env()->ClassCastException_instance();
 525       }
 526       break;
 527     }
 528     if (failing()) { stop(); return; }  // exception allocation might fail
 529     if (ex_obj != NULL) {
 530       // Cheat with a preallocated exception object.
 531       if (C->log() != NULL)
 532         C->log()->elem("hot_throw preallocated='1' reason='%s'",
 533                        Deoptimization::trap_reason_name(reason));
 534       const TypeInstPtr* ex_con  = TypeInstPtr::make(ex_obj);
 535       Node*              ex_node = _gvn.transform( ConNode::make(C, ex_con) );
 536 
 537       // Clear the detail message of the preallocated exception object.
 538       // Weblogic sometimes mutates the detail message of exceptions
 539       // using reflection.
 540       int offset = java_lang_Throwable::get_detailMessage_offset();
 541       const TypePtr* adr_typ = ex_con->add_offset(offset);
 542 
 543       Node *adr = basic_plus_adr(ex_node, ex_node, offset);
 544       Node *store = store_oop_to_object(control(), ex_node, adr, adr_typ, null(), ex_con, T_OBJECT);
 545 
 546       add_exception_state(make_exception_state(ex_node));
 547       return;
 548     }
 549   }
 550 
 551   // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
 552   // It won't be much cheaper than bailing to the interp., since we'll
 553   // have to pass up all the debug-info, and the runtime will have to
 554   // create the stack trace.
 555 
 556   // Usual case:  Bail to interpreter.
 557   // Reserve the right to recompile if we haven't seen anything yet.
 558 
 559   Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
 560   if (treat_throw_as_hot
 561       && (method()->method_data()->trap_recompiled_at(bci())
 562           || C->too_many_traps(reason))) {
 563     // We cannot afford to take more traps here.  Suffer in the interpreter.
 564     if (C->log() != NULL)
 565       C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
 566                      Deoptimization::trap_reason_name(reason),
 567                      C->trap_count(reason));
 568     action = Deoptimization::Action_none;
 569   }
 570 
 571   // "must_throw" prunes the JVM state to include only the stack, if there
 572   // are no local exception handlers.  This should cut down on register
 573   // allocation time and code size, by drastically reducing the number
 574   // of in-edges on the call to the uncommon trap.
 575 
 576   uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw);
 577 }
 578 
 579 
 580 //----------------------------PreserveJVMState---------------------------------
 581 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
 582   debug_only(kit->verify_map());
 583   _kit    = kit;
 584   _map    = kit->map();   // preserve the map
 585   _sp     = kit->sp();
 586   kit->set_map(clone_map ? kit->clone_map() : NULL);
 587 #ifdef ASSERT
 588   _bci    = kit->bci();
 589   Parse* parser = kit->is_Parse();
 590   int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
 591   _block  = block;
 592 #endif
 593 }
 594 PreserveJVMState::~PreserveJVMState() {
 595   GraphKit* kit = _kit;
 596 #ifdef ASSERT
 597   assert(kit->bci() == _bci, "bci must not shift");
 598   Parse* parser = kit->is_Parse();
 599   int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
 600   assert(block == _block,    "block must not shift");
 601 #endif
 602   kit->set_map(_map);
 603   kit->set_sp(_sp);
 604 }
 605 
 606 
 607 //-----------------------------BuildCutout-------------------------------------
 608 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
 609   : PreserveJVMState(kit)
 610 {
 611   assert(p->is_Con() || p->is_Bool(), "test must be a bool");
 612   SafePointNode* outer_map = _map;   // preserved map is caller's
 613   SafePointNode* inner_map = kit->map();
 614   IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
 615   outer_map->set_control(kit->gvn().transform( new (kit->C, 1) IfTrueNode(iff) ));
 616   inner_map->set_control(kit->gvn().transform( new (kit->C, 1) IfFalseNode(iff) ));
 617 }
 618 BuildCutout::~BuildCutout() {
 619   GraphKit* kit = _kit;
 620   assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
 621 }
 622 
 623 //---------------------------PreserveReexecuteState----------------------------
 624 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
 625   assert(!kit->stopped(), "must call stopped() before");
 626   _kit    =    kit;
 627   _sp     =    kit->sp();
 628   _reexecute = kit->jvms()->_reexecute;
 629 }
 630 PreserveReexecuteState::~PreserveReexecuteState() {
 631   if (_kit->stopped()) return;
 632   _kit->jvms()->_reexecute = _reexecute;
 633   _kit->set_sp(_sp);
 634 }
 635 
 636 //------------------------------clone_map--------------------------------------
 637 // Implementation of PreserveJVMState
 638 //
 639 // Only clone_map(...) here. If this function is only used in the
 640 // PreserveJVMState class we may want to get rid of this extra
 641 // function eventually and do it all there.
 642 
 643 SafePointNode* GraphKit::clone_map() {
 644   if (map() == NULL)  return NULL;
 645 
 646   // Clone the memory edge first
 647   Node* mem = MergeMemNode::make(C, map()->memory());
 648   gvn().set_type_bottom(mem);
 649 
 650   SafePointNode *clonemap = (SafePointNode*)map()->clone();
 651   JVMState* jvms = this->jvms();
 652   JVMState* clonejvms = jvms->clone_shallow(C);
 653   clonemap->set_memory(mem);
 654   clonemap->set_jvms(clonejvms);
 655   clonejvms->set_map(clonemap);
 656   record_for_igvn(clonemap);
 657   gvn().set_type_bottom(clonemap);
 658   return clonemap;
 659 }
 660 
 661 
 662 //-----------------------------set_map_clone-----------------------------------
 663 void GraphKit::set_map_clone(SafePointNode* m) {
 664   _map = m;
 665   _map = clone_map();
 666   _map->set_next_exception(NULL);
 667   debug_only(verify_map());
 668 }
 669 
 670 
 671 //----------------------------kill_dead_locals---------------------------------
 672 // Detect any locals which are known to be dead, and force them to top.
 673 void GraphKit::kill_dead_locals() {
 674   // Consult the liveness information for the locals.  If any
 675   // of them are unused, then they can be replaced by top().  This
 676   // should help register allocation time and cut down on the size
 677   // of the deoptimization information.
 678 
 679   // This call is made from many of the bytecode handling
 680   // subroutines called from the Big Switch in do_one_bytecode.
 681   // Every bytecode which might include a slow path is responsible
 682   // for killing its dead locals.  The more consistent we
 683   // are about killing deads, the fewer useless phis will be
 684   // constructed for them at various merge points.
 685 
 686   // bci can be -1 (InvocationEntryBci).  We return the entry
 687   // liveness for the method.
 688 
 689   if (method() == NULL || method()->code_size() == 0) {
 690     // We are building a graph for a call to a native method.
 691     // All locals are live.
 692     return;
 693   }
 694 
 695   ResourceMark rm;
 696 
 697   // Consult the liveness information for the locals.  If any
 698   // of them are unused, then they can be replaced by top().  This
 699   // should help register allocation time and cut down on the size
 700   // of the deoptimization information.
 701   MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
 702 
 703   int len = (int)live_locals.size();
 704   assert(len <= jvms()->loc_size(), "too many live locals");
 705   for (int local = 0; local < len; local++) {
 706     if (!live_locals.at(local)) {
 707       set_local(local, top());
 708     }
 709   }
 710 }
 711 
 712 #ifdef ASSERT
 713 //-------------------------dead_locals_are_killed------------------------------
 714 // Return true if all dead locals are set to top in the map.
 715 // Used to assert "clean" debug info at various points.
 716 bool GraphKit::dead_locals_are_killed() {
 717   if (method() == NULL || method()->code_size() == 0) {
 718     // No locals need to be dead, so all is as it should be.
 719     return true;
 720   }
 721 
 722   // Make sure somebody called kill_dead_locals upstream.
 723   ResourceMark rm;
 724   for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
 725     if (jvms->loc_size() == 0)  continue;  // no locals to consult
 726     SafePointNode* map = jvms->map();
 727     ciMethod* method = jvms->method();
 728     int       bci    = jvms->bci();
 729     if (jvms == this->jvms()) {
 730       bci = this->bci();  // it might not yet be synched
 731     }
 732     MethodLivenessResult live_locals = method->liveness_at_bci(bci);
 733     int len = (int)live_locals.size();
 734     if (!live_locals.is_valid() || len == 0)
 735       // This method is trivial, or is poisoned by a breakpoint.
 736       return true;
 737     assert(len == jvms->loc_size(), "live map consistent with locals map");
 738     for (int local = 0; local < len; local++) {
 739       if (!live_locals.at(local) && map->local(jvms, local) != top()) {
 740         if (PrintMiscellaneous && (Verbose || WizardMode)) {
 741           tty->print_cr("Zombie local %d: ", local);
 742           jvms->dump();
 743         }
 744         return false;
 745       }
 746     }
 747   }
 748   return true;
 749 }
 750 
 751 #endif //ASSERT
 752 
 753 // Helper function for enforcing certain bytecodes to reexecute if
 754 // deoptimization happens
 755 static bool should_reexecute_implied_by_bytecode(JVMState *jvms) {
 756   ciMethod* cur_method = jvms->method();
 757   int       cur_bci   = jvms->bci();
 758   if (cur_method != NULL && cur_bci != InvocationEntryBci) {
 759     Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
 760     return Interpreter::bytecode_should_reexecute(code);
 761   } else
 762     return false;
 763 }
 764 
 765 // Helper function for adding JVMState and debug information to node
 766 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
 767   // Add the safepoint edges to the call (or other safepoint).
 768 
 769   // Make sure dead locals are set to top.  This
 770   // should help register allocation time and cut down on the size
 771   // of the deoptimization information.
 772   assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
 773 
 774   // Walk the inline list to fill in the correct set of JVMState's
 775   // Also fill in the associated edges for each JVMState.
 776 
 777   JVMState* youngest_jvms = sync_jvms();
 778 
 779   // Do we need debug info here?  If it is a SafePoint and this method
 780   // cannot de-opt, then we do NOT need any debug info.
 781   bool full_info = (C->deopt_happens() || call->Opcode() != Op_SafePoint);
 782 
 783   // If we are guaranteed to throw, we can prune everything but the
 784   // input to the current bytecode.
 785   bool can_prune_locals = false;
 786   uint stack_slots_not_pruned = 0;
 787   int inputs = 0, depth = 0;
 788   if (must_throw) {
 789     assert(method() == youngest_jvms->method(), "sanity");
 790     if (compute_stack_effects(inputs, depth)) {
 791       can_prune_locals = true;
 792       stack_slots_not_pruned = inputs;
 793     }
 794   }
 795 
 796   if (env()->jvmti_can_examine_or_deopt_anywhere()) {
 797     // At any safepoint, this method can get breakpointed, which would
 798     // then require an immediate deoptimization.
 799     full_info = true;
 800     can_prune_locals = false;  // do not prune locals
 801     stack_slots_not_pruned = 0;
 802   }
 803 
 804   // do not scribble on the input jvms
 805   JVMState* out_jvms = youngest_jvms->clone_deep(C);
 806   call->set_jvms(out_jvms); // Start jvms list for call node
 807 
 808   // For a known set of bytecodes, the interpreter should reexecute them if
 809   // deoptimization happens. We set the reexecute state for them here
 810   if (out_jvms->is_reexecute_undefined() && //don't change if already specified
 811       should_reexecute_implied_by_bytecode(out_jvms)) {
 812     out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
 813   }
 814 
 815   // Presize the call:
 816   debug_only(uint non_debug_edges = call->req());
 817   call->add_req_batch(top(), youngest_jvms->debug_depth());
 818   assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
 819 
 820   // Set up edges so that the call looks like this:
 821   //  Call [state:] ctl io mem fptr retadr
 822   //       [parms:] parm0 ... parmN
 823   //       [root:]  loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 824   //    [...mid:]   loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
 825   //       [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 826   // Note that caller debug info precedes callee debug info.
 827 
 828   // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
 829   uint debug_ptr = call->req();
 830 
 831   // Loop over the map input edges associated with jvms, add them
 832   // to the call node, & reset all offsets to match call node array.
 833   for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) {
 834     uint debug_end   = debug_ptr;
 835     uint debug_start = debug_ptr - in_jvms->debug_size();
 836     debug_ptr = debug_start;  // back up the ptr
 837 
 838     uint p = debug_start;  // walks forward in [debug_start, debug_end)
 839     uint j, k, l;
 840     SafePointNode* in_map = in_jvms->map();
 841     out_jvms->set_map(call);
 842 
 843     if (can_prune_locals) {
 844       assert(in_jvms->method() == out_jvms->method(), "sanity");
 845       // If the current throw can reach an exception handler in this JVMS,
 846       // then we must keep everything live that can reach that handler.
 847       // As a quick and dirty approximation, we look for any handlers at all.
 848       if (in_jvms->method()->has_exception_handlers()) {
 849         can_prune_locals = false;
 850       }
 851     }
 852 
 853     // Add the Locals
 854     k = in_jvms->locoff();
 855     l = in_jvms->loc_size();
 856     out_jvms->set_locoff(p);
 857     if (full_info && !can_prune_locals) {
 858       for (j = 0; j < l; j++)
 859         call->set_req(p++, in_map->in(k+j));
 860     } else {
 861       p += l;  // already set to top above by add_req_batch
 862     }
 863 
 864     // Add the Expression Stack
 865     k = in_jvms->stkoff();
 866     l = in_jvms->sp();
 867     out_jvms->set_stkoff(p);
 868     if (full_info && !can_prune_locals) {
 869       for (j = 0; j < l; j++)
 870         call->set_req(p++, in_map->in(k+j));
 871     } else if (can_prune_locals && stack_slots_not_pruned != 0) {
 872       // Divide stack into {S0,...,S1}, where S0 is set to top.
 873       uint s1 = stack_slots_not_pruned;
 874       stack_slots_not_pruned = 0;  // for next iteration
 875       if (s1 > l)  s1 = l;
 876       uint s0 = l - s1;
 877       p += s0;  // skip the tops preinstalled by add_req_batch
 878       for (j = s0; j < l; j++)
 879         call->set_req(p++, in_map->in(k+j));
 880     } else {
 881       p += l;  // already set to top above by add_req_batch
 882     }
 883 
 884     // Add the Monitors
 885     k = in_jvms->monoff();
 886     l = in_jvms->mon_size();
 887     out_jvms->set_monoff(p);
 888     for (j = 0; j < l; j++)
 889       call->set_req(p++, in_map->in(k+j));
 890 
 891     // Copy any scalar object fields.
 892     k = in_jvms->scloff();
 893     l = in_jvms->scl_size();
 894     out_jvms->set_scloff(p);
 895     for (j = 0; j < l; j++)
 896       call->set_req(p++, in_map->in(k+j));
 897 
 898     // Finish the new jvms.
 899     out_jvms->set_endoff(p);
 900 
 901     assert(out_jvms->endoff()     == debug_end,             "fill ptr must match");
 902     assert(out_jvms->depth()      == in_jvms->depth(),      "depth must match");
 903     assert(out_jvms->loc_size()   == in_jvms->loc_size(),   "size must match");
 904     assert(out_jvms->mon_size()   == in_jvms->mon_size(),   "size must match");
 905     assert(out_jvms->scl_size()   == in_jvms->scl_size(),   "size must match");
 906     assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
 907 
 908     // Update the two tail pointers in parallel.
 909     out_jvms = out_jvms->caller();
 910     in_jvms  = in_jvms->caller();
 911   }
 912 
 913   assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
 914 
 915   // Test the correctness of JVMState::debug_xxx accessors:
 916   assert(call->jvms()->debug_start() == non_debug_edges, "");
 917   assert(call->jvms()->debug_end()   == call->req(), "");
 918   assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
 919 }
 920 
 921 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
 922   Bytecodes::Code code = java_bc();
 923   if (code == Bytecodes::_wide) {
 924     code = method()->java_code_at_bci(bci() + 1);
 925   }
 926 
 927   BasicType rtype = T_ILLEGAL;
 928   int       rsize = 0;
 929 
 930   if (code != Bytecodes::_illegal) {
 931     depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
 932     rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
 933     if (rtype < T_CONFLICT)
 934       rsize = type2size[rtype];
 935   }
 936 
 937   switch (code) {
 938   case Bytecodes::_illegal:
 939     return false;
 940 
 941   case Bytecodes::_ldc:
 942   case Bytecodes::_ldc_w:
 943   case Bytecodes::_ldc2_w:
 944     inputs = 0;
 945     break;
 946 
 947   case Bytecodes::_dup:         inputs = 1;  break;
 948   case Bytecodes::_dup_x1:      inputs = 2;  break;
 949   case Bytecodes::_dup_x2:      inputs = 3;  break;
 950   case Bytecodes::_dup2:        inputs = 2;  break;
 951   case Bytecodes::_dup2_x1:     inputs = 3;  break;
 952   case Bytecodes::_dup2_x2:     inputs = 4;  break;
 953   case Bytecodes::_swap:        inputs = 2;  break;
 954   case Bytecodes::_arraylength: inputs = 1;  break;
 955 
 956   case Bytecodes::_getstatic:
 957   case Bytecodes::_putstatic:
 958   case Bytecodes::_getfield:
 959   case Bytecodes::_putfield:
 960     {
 961       bool is_get = (depth >= 0), is_static = (depth & 1);
 962       bool ignore;
 963       ciBytecodeStream iter(method());
 964       iter.reset_to_bci(bci());
 965       iter.next();
 966       ciField* field = iter.get_field(ignore);
 967       int      size  = field->type()->size();
 968       inputs  = (is_static ? 0 : 1);
 969       if (is_get) {
 970         depth = size - inputs;
 971       } else {
 972         inputs += size;        // putxxx pops the value from the stack
 973         depth = - inputs;
 974       }
 975     }
 976     break;
 977 
 978   case Bytecodes::_invokevirtual:
 979   case Bytecodes::_invokespecial:
 980   case Bytecodes::_invokestatic:
 981   case Bytecodes::_invokedynamic:
 982   case Bytecodes::_invokeinterface:
 983     {
 984       bool is_static = (depth == 0);
 985       bool ignore;
 986       ciBytecodeStream iter(method());
 987       iter.reset_to_bci(bci());
 988       iter.next();
 989       ciMethod* method = iter.get_method(ignore);
 990       inputs = method->arg_size_no_receiver();
 991       if (!is_static)  inputs += 1;
 992       int size = method->return_type()->size();
 993       depth = size - inputs;
 994     }
 995     break;
 996 
 997   case Bytecodes::_multianewarray:
 998     {
 999       ciBytecodeStream iter(method());
1000       iter.reset_to_bci(bci());
1001       iter.next();
1002       inputs = iter.get_dimensions();
1003       assert(rsize == 1, "");
1004       depth = rsize - inputs;
1005     }
1006     break;
1007 
1008   case Bytecodes::_ireturn:
1009   case Bytecodes::_lreturn:
1010   case Bytecodes::_freturn:
1011   case Bytecodes::_dreturn:
1012   case Bytecodes::_areturn:
1013     assert(rsize = -depth, "");
1014     inputs = rsize;
1015     break;
1016 
1017   case Bytecodes::_jsr:
1018   case Bytecodes::_jsr_w:
1019     inputs = 0;
1020     depth  = 1;                  // S.B. depth=1, not zero
1021     break;
1022 
1023   default:
1024     // bytecode produces a typed result
1025     inputs = rsize - depth;
1026     assert(inputs >= 0, "");
1027     break;
1028   }
1029 
1030 #ifdef ASSERT
1031   // spot check
1032   int outputs = depth + inputs;
1033   assert(outputs >= 0, "sanity");
1034   switch (code) {
1035   case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1036   case Bytecodes::_athrow:    assert(inputs == 1 && outputs == 0, ""); break;
1037   case Bytecodes::_aload_0:   assert(inputs == 0 && outputs == 1, ""); break;
1038   case Bytecodes::_return:    assert(inputs == 0 && outputs == 0, ""); break;
1039   case Bytecodes::_drem:      assert(inputs == 4 && outputs == 2, ""); break;
1040   }
1041 #endif //ASSERT
1042 
1043   return true;
1044 }
1045 
1046 
1047 
1048 //------------------------------basic_plus_adr---------------------------------
1049 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1050   // short-circuit a common case
1051   if (offset == intcon(0))  return ptr;
1052   return _gvn.transform( new (C, 4) AddPNode(base, ptr, offset) );
1053 }
1054 
1055 Node* GraphKit::ConvI2L(Node* offset) {
1056   // short-circuit a common case
1057   jint offset_con = find_int_con(offset, Type::OffsetBot);
1058   if (offset_con != Type::OffsetBot) {
1059     return longcon((long) offset_con);
1060   }
1061   return _gvn.transform( new (C, 2) ConvI2LNode(offset));
1062 }
1063 Node* GraphKit::ConvL2I(Node* offset) {
1064   // short-circuit a common case
1065   jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1066   if (offset_con != (jlong)Type::OffsetBot) {
1067     return intcon((int) offset_con);
1068   }
1069   return _gvn.transform( new (C, 2) ConvL2INode(offset));
1070 }
1071 
1072 //-------------------------load_object_klass-----------------------------------
1073 Node* GraphKit::load_object_klass(Node* obj) {
1074   // Special-case a fresh allocation to avoid building nodes:
1075   Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1076   if (akls != NULL)  return akls;
1077   Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1078   return _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), k_adr, TypeInstPtr::KLASS) );
1079 }
1080 
1081 //-------------------------load_array_length-----------------------------------
1082 Node* GraphKit::load_array_length(Node* array) {
1083   // Special-case a fresh allocation to avoid building nodes:
1084   AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn);
1085   Node *alen;
1086   if (alloc == NULL) {
1087     Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1088     alen = _gvn.transform( new (C, 3) LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1089   } else {
1090     alen = alloc->Ideal_length();
1091     Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn);
1092     if (ccast != alen) {
1093       alen = _gvn.transform(ccast);
1094     }
1095   }
1096   return alen;
1097 }
1098 
1099 //------------------------------do_null_check----------------------------------
1100 // Helper function to do a NULL pointer check.  Returned value is
1101 // the incoming address with NULL casted away.  You are allowed to use the
1102 // not-null value only if you are control dependent on the test.
1103 extern int explicit_null_checks_inserted,
1104            explicit_null_checks_elided;
1105 Node* GraphKit::null_check_common(Node* value, BasicType type,
1106                                   // optional arguments for variations:
1107                                   bool assert_null,
1108                                   Node* *null_control) {
1109   assert(!assert_null || null_control == NULL, "not both at once");
1110   if (stopped())  return top();
1111   if (!GenerateCompilerNullChecks && !assert_null && null_control == NULL) {
1112     // For some performance testing, we may wish to suppress null checking.
1113     value = cast_not_null(value);   // Make it appear to be non-null (4962416).
1114     return value;
1115   }
1116   explicit_null_checks_inserted++;
1117 
1118   // Construct NULL check
1119   Node *chk = NULL;
1120   switch(type) {
1121     case T_LONG   : chk = new (C, 3) CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1122     case T_INT    : chk = new (C, 3) CmpINode( value, _gvn.intcon(0)); break;
1123     case T_ARRAY  : // fall through
1124       type = T_OBJECT;  // simplify further tests
1125     case T_OBJECT : {
1126       const Type *t = _gvn.type( value );
1127 
1128       const TypeOopPtr* tp = t->isa_oopptr();
1129       if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded()
1130           // Only for do_null_check, not any of its siblings:
1131           && !assert_null && null_control == NULL) {
1132         // Usually, any field access or invocation on an unloaded oop type
1133         // will simply fail to link, since the statically linked class is
1134         // likely also to be unloaded.  However, in -Xcomp mode, sometimes
1135         // the static class is loaded but the sharper oop type is not.
1136         // Rather than checking for this obscure case in lots of places,
1137         // we simply observe that a null check on an unloaded class
1138         // will always be followed by a nonsense operation, so we
1139         // can just issue the uncommon trap here.
1140         // Our access to the unloaded class will only be correct
1141         // after it has been loaded and initialized, which requires
1142         // a trip through the interpreter.
1143 #ifndef PRODUCT
1144         if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); }
1145 #endif
1146         uncommon_trap(Deoptimization::Reason_unloaded,
1147                       Deoptimization::Action_reinterpret,
1148                       tp->klass(), "!loaded");
1149         return top();
1150       }
1151 
1152       if (assert_null) {
1153         // See if the type is contained in NULL_PTR.
1154         // If so, then the value is already null.
1155         if (t->higher_equal(TypePtr::NULL_PTR)) {
1156           explicit_null_checks_elided++;
1157           return value;           // Elided null assert quickly!
1158         }
1159       } else {
1160         // See if mixing in the NULL pointer changes type.
1161         // If so, then the NULL pointer was not allowed in the original
1162         // type.  In other words, "value" was not-null.
1163         if (t->meet(TypePtr::NULL_PTR) != t) {
1164           // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1165           explicit_null_checks_elided++;
1166           return value;           // Elided null check quickly!
1167         }
1168       }
1169       chk = new (C, 3) CmpPNode( value, null() );
1170       break;
1171     }
1172 
1173     default      : ShouldNotReachHere();
1174   }
1175   assert(chk != NULL, "sanity check");
1176   chk = _gvn.transform(chk);
1177 
1178   BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1179   BoolNode *btst = new (C, 2) BoolNode( chk, btest);
1180   Node   *tst = _gvn.transform( btst );
1181 
1182   //-----------
1183   // if peephole optimizations occurred, a prior test existed.
1184   // If a prior test existed, maybe it dominates as we can avoid this test.
1185   if (tst != btst && type == T_OBJECT) {
1186     // At this point we want to scan up the CFG to see if we can
1187     // find an identical test (and so avoid this test altogether).
1188     Node *cfg = control();
1189     int depth = 0;
1190     while( depth < 16 ) {       // Limit search depth for speed
1191       if( cfg->Opcode() == Op_IfTrue &&
1192           cfg->in(0)->in(1) == tst ) {
1193         // Found prior test.  Use "cast_not_null" to construct an identical
1194         // CastPP (and hence hash to) as already exists for the prior test.
1195         // Return that casted value.
1196         if (assert_null) {
1197           replace_in_map(value, null());
1198           return null();  // do not issue the redundant test
1199         }
1200         Node *oldcontrol = control();
1201         set_control(cfg);
1202         Node *res = cast_not_null(value);
1203         set_control(oldcontrol);
1204         explicit_null_checks_elided++;
1205         return res;
1206       }
1207       cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1208       if (cfg == NULL)  break;  // Quit at region nodes
1209       depth++;
1210     }
1211   }
1212 
1213   //-----------
1214   // Branch to failure if null
1215   float ok_prob = PROB_MAX;  // a priori estimate:  nulls never happen
1216   Deoptimization::DeoptReason reason;
1217   if (assert_null)
1218     reason = Deoptimization::Reason_null_assert;
1219   else if (type == T_OBJECT)
1220     reason = Deoptimization::Reason_null_check;
1221   else
1222     reason = Deoptimization::Reason_div0_check;
1223 
1224   // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1225   // ciMethodData::has_trap_at will return a conservative -1 if any
1226   // must-be-null assertion has failed.  This could cause performance
1227   // problems for a method after its first do_null_assert failure.
1228   // Consider using 'Reason_class_check' instead?
1229 
1230   // To cause an implicit null check, we set the not-null probability
1231   // to the maximum (PROB_MAX).  For an explicit check the probability
1232   // is set to a smaller value.
1233   if (null_control != NULL || too_many_traps(reason)) {
1234     // probability is less likely
1235     ok_prob =  PROB_LIKELY_MAG(3);
1236   } else if (!assert_null &&
1237              (ImplicitNullCheckThreshold > 0) &&
1238              method() != NULL &&
1239              (method()->method_data()->trap_count(reason)
1240               >= (uint)ImplicitNullCheckThreshold)) {
1241     ok_prob =  PROB_LIKELY_MAG(3);
1242   }
1243 
1244   if (null_control != NULL) {
1245     IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1246     Node* null_true = _gvn.transform( new (C, 1) IfFalseNode(iff));
1247     set_control(      _gvn.transform( new (C, 1) IfTrueNode(iff)));
1248     if (null_true == top())
1249       explicit_null_checks_elided++;
1250     (*null_control) = null_true;
1251   } else {
1252     BuildCutout unless(this, tst, ok_prob);
1253     // Check for optimizer eliding test at parse time
1254     if (stopped()) {
1255       // Failure not possible; do not bother making uncommon trap.
1256       explicit_null_checks_elided++;
1257     } else if (assert_null) {
1258       uncommon_trap(reason,
1259                     Deoptimization::Action_make_not_entrant,
1260                     NULL, "assert_null");
1261     } else {
1262       replace_in_map(value, zerocon(type));
1263       builtin_throw(reason);
1264     }
1265   }
1266 
1267   // Must throw exception, fall-thru not possible?
1268   if (stopped()) {
1269     return top();               // No result
1270   }
1271 
1272   if (assert_null) {
1273     // Cast obj to null on this path.
1274     replace_in_map(value, zerocon(type));
1275     return zerocon(type);
1276   }
1277 
1278   // Cast obj to not-null on this path, if there is no null_control.
1279   // (If there is a null_control, a non-null value may come back to haunt us.)
1280   if (type == T_OBJECT) {
1281     Node* cast = cast_not_null(value, false);
1282     if (null_control == NULL || (*null_control) == top())
1283       replace_in_map(value, cast);
1284     value = cast;
1285   }
1286 
1287   return value;
1288 }
1289 
1290 
1291 //------------------------------cast_not_null----------------------------------
1292 // Cast obj to not-null on this path
1293 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1294   const Type *t = _gvn.type(obj);
1295   const Type *t_not_null = t->join(TypePtr::NOTNULL);
1296   // Object is already not-null?
1297   if( t == t_not_null ) return obj;
1298 
1299   Node *cast = new (C, 2) CastPPNode(obj,t_not_null);
1300   cast->init_req(0, control());
1301   cast = _gvn.transform( cast );
1302 
1303   // Scan for instances of 'obj' in the current JVM mapping.
1304   // These instances are known to be not-null after the test.
1305   if (do_replace_in_map)
1306     replace_in_map(obj, cast);
1307 
1308   return cast;                  // Return casted value
1309 }
1310 
1311 
1312 //--------------------------replace_in_map-------------------------------------
1313 void GraphKit::replace_in_map(Node* old, Node* neww) {
1314   this->map()->replace_edge(old, neww);
1315 
1316   // Note: This operation potentially replaces any edge
1317   // on the map.  This includes locals, stack, and monitors
1318   // of the current (innermost) JVM state.
1319 
1320   // We can consider replacing in caller maps.
1321   // The idea would be that an inlined function's null checks
1322   // can be shared with the entire inlining tree.
1323   // The expense of doing this is that the PreserveJVMState class
1324   // would have to preserve caller states too, with a deep copy.
1325 }
1326 
1327 
1328 
1329 //=============================================================================
1330 //--------------------------------memory---------------------------------------
1331 Node* GraphKit::memory(uint alias_idx) {
1332   MergeMemNode* mem = merged_memory();
1333   Node* p = mem->memory_at(alias_idx);
1334   _gvn.set_type(p, Type::MEMORY);  // must be mapped
1335   return p;
1336 }
1337 
1338 //-----------------------------reset_memory------------------------------------
1339 Node* GraphKit::reset_memory() {
1340   Node* mem = map()->memory();
1341   // do not use this node for any more parsing!
1342   debug_only( map()->set_memory((Node*)NULL) );
1343   return _gvn.transform( mem );
1344 }
1345 
1346 //------------------------------set_all_memory---------------------------------
1347 void GraphKit::set_all_memory(Node* newmem) {
1348   Node* mergemem = MergeMemNode::make(C, newmem);
1349   gvn().set_type_bottom(mergemem);
1350   map()->set_memory(mergemem);
1351 }
1352 
1353 //------------------------------set_all_memory_call----------------------------
1354 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1355   Node* newmem = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1356   set_all_memory(newmem);
1357 }
1358 
1359 //=============================================================================
1360 //
1361 // parser factory methods for MemNodes
1362 //
1363 // These are layered on top of the factory methods in LoadNode and StoreNode,
1364 // and integrate with the parser's memory state and _gvn engine.
1365 //
1366 
1367 // factory methods in "int adr_idx"
1368 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1369                           int adr_idx,
1370                           bool require_atomic_access) {
1371   assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1372   const TypePtr* adr_type = NULL; // debug-mode-only argument
1373   debug_only(adr_type = C->get_adr_type(adr_idx));
1374   Node* mem = memory(adr_idx);
1375   Node* ld;
1376   if (require_atomic_access && bt == T_LONG) {
1377     ld = LoadLNode::make_atomic(C, ctl, mem, adr, adr_type, t);
1378   } else {
1379     ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt);
1380   }
1381   return _gvn.transform(ld);
1382 }
1383 
1384 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1385                                 int adr_idx,
1386                                 bool require_atomic_access) {
1387   assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1388   const TypePtr* adr_type = NULL;
1389   debug_only(adr_type = C->get_adr_type(adr_idx));
1390   Node *mem = memory(adr_idx);
1391   Node* st;
1392   if (require_atomic_access && bt == T_LONG) {
1393     st = StoreLNode::make_atomic(C, ctl, mem, adr, adr_type, val);
1394   } else {
1395     st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt);
1396   }
1397   st = _gvn.transform(st);
1398   set_memory(st, adr_idx);
1399   // Back-to-back stores can only remove intermediate store with DU info
1400   // so push on worklist for optimizer.
1401   if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1402     record_for_igvn(st);
1403 
1404   return st;
1405 }
1406 
1407 
1408 void GraphKit::pre_barrier(Node* ctl,
1409                            Node* obj,
1410                            Node* adr,
1411                            uint  adr_idx,
1412                            Node* val,
1413                            const TypeOopPtr* val_type,
1414                            BasicType bt) {
1415   BarrierSet* bs = Universe::heap()->barrier_set();
1416   set_control(ctl);
1417   switch (bs->kind()) {
1418     case BarrierSet::G1SATBCT:
1419     case BarrierSet::G1SATBCTLogging:
1420       g1_write_barrier_pre(obj, adr, adr_idx, val, val_type, bt);
1421       break;
1422 
1423     case BarrierSet::CardTableModRef:
1424     case BarrierSet::CardTableExtension:
1425     case BarrierSet::ModRef:
1426       break;
1427 
1428     case BarrierSet::Other:
1429     default      :
1430       ShouldNotReachHere();
1431 
1432   }
1433 }
1434 
1435 void GraphKit::post_barrier(Node* ctl,
1436                             Node* store,
1437                             Node* obj,
1438                             Node* adr,
1439                             uint  adr_idx,
1440                             Node* val,
1441                             BasicType bt,
1442                             bool use_precise) {
1443   BarrierSet* bs = Universe::heap()->barrier_set();
1444   set_control(ctl);
1445   switch (bs->kind()) {
1446     case BarrierSet::G1SATBCT:
1447     case BarrierSet::G1SATBCTLogging:
1448       g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise);
1449       break;
1450 
1451     case BarrierSet::CardTableModRef:
1452     case BarrierSet::CardTableExtension:
1453       write_barrier_post(store, obj, adr, adr_idx, val, use_precise);
1454       break;
1455 
1456     case BarrierSet::ModRef:
1457       break;
1458 
1459     case BarrierSet::Other:
1460     default      :
1461       ShouldNotReachHere();
1462 
1463   }
1464 }
1465 
1466 Node* GraphKit::store_oop(Node* ctl,
1467                           Node* obj,
1468                           Node* adr,
1469                           const TypePtr* adr_type,
1470                           Node* val,
1471                           const TypeOopPtr* val_type,
1472                           BasicType bt,
1473                           bool use_precise) {
1474 
1475   set_control(ctl);
1476   if (stopped()) return top(); // Dead path ?
1477 
1478   assert(bt == T_OBJECT, "sanity");
1479   assert(val != NULL, "not dead path");
1480   uint adr_idx = C->get_alias_index(adr_type);
1481   assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1482 
1483   pre_barrier(control(), obj, adr, adr_idx, val, val_type, bt);
1484   Node* store = store_to_memory(control(), adr, val, bt, adr_idx);
1485   post_barrier(control(), store, obj, adr, adr_idx, val, bt, use_precise);
1486   return store;
1487 }
1488 
1489 // Could be an array or object we don't know at compile time (unsafe ref.)
1490 Node* GraphKit::store_oop_to_unknown(Node* ctl,
1491                              Node* obj,   // containing obj
1492                              Node* adr,  // actual adress to store val at
1493                              const TypePtr* adr_type,
1494                              Node* val,
1495                              BasicType bt) {
1496   Compile::AliasType* at = C->alias_type(adr_type);
1497   const TypeOopPtr* val_type = NULL;
1498   if (adr_type->isa_instptr()) {
1499     if (at->field() != NULL) {
1500       // known field.  This code is a copy of the do_put_xxx logic.
1501       ciField* field = at->field();
1502       if (!field->type()->is_loaded()) {
1503         val_type = TypeInstPtr::BOTTOM;
1504       } else {
1505         val_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
1506       }
1507     }
1508   } else if (adr_type->isa_aryptr()) {
1509     val_type = adr_type->is_aryptr()->elem()->make_oopptr();
1510   }
1511   if (val_type == NULL) {
1512     val_type = TypeInstPtr::BOTTOM;
1513   }
1514   return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true);
1515 }
1516 
1517 
1518 //-------------------------array_element_address-------------------------
1519 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1520                                       const TypeInt* sizetype) {
1521   uint shift  = exact_log2(type2aelembytes(elembt));
1522   uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1523 
1524   // short-circuit a common case (saves lots of confusing waste motion)
1525   jint idx_con = find_int_con(idx, -1);
1526   if (idx_con >= 0) {
1527     intptr_t offset = header + ((intptr_t)idx_con << shift);
1528     return basic_plus_adr(ary, offset);
1529   }
1530 
1531   // must be correct type for alignment purposes
1532   Node* base  = basic_plus_adr(ary, header);
1533 #ifdef _LP64
1534   // The scaled index operand to AddP must be a clean 64-bit value.
1535   // Java allows a 32-bit int to be incremented to a negative
1536   // value, which appears in a 64-bit register as a large
1537   // positive number.  Using that large positive number as an
1538   // operand in pointer arithmetic has bad consequences.
1539   // On the other hand, 32-bit overflow is rare, and the possibility
1540   // can often be excluded, if we annotate the ConvI2L node with
1541   // a type assertion that its value is known to be a small positive
1542   // number.  (The prior range check has ensured this.)
1543   // This assertion is used by ConvI2LNode::Ideal.
1544   int index_max = max_jint - 1;  // array size is max_jint, index is one less
1545   if (sizetype != NULL)  index_max = sizetype->_hi - 1;
1546   const TypeLong* lidxtype = TypeLong::make(CONST64(0), index_max, Type::WidenMax);
1547   idx = _gvn.transform( new (C, 2) ConvI2LNode(idx, lidxtype) );
1548 #endif
1549   Node* scale = _gvn.transform( new (C, 3) LShiftXNode(idx, intcon(shift)) );
1550   return basic_plus_adr(ary, base, scale);
1551 }
1552 
1553 //-------------------------load_array_element-------------------------
1554 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) {
1555   const Type* elemtype = arytype->elem();
1556   BasicType elembt = elemtype->array_element_basic_type();
1557   Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1558   Node* ld = make_load(ctl, adr, elemtype, elembt, arytype);
1559   return ld;
1560 }
1561 
1562 //-------------------------set_arguments_for_java_call-------------------------
1563 // Arguments (pre-popped from the stack) are taken from the JVMS.
1564 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1565   // Add the call arguments:
1566   uint nargs = call->method()->arg_size();
1567   for (uint i = 0; i < nargs; i++) {
1568     Node* arg = argument(i);
1569     call->init_req(i + TypeFunc::Parms, arg);
1570   }
1571 }
1572 
1573 //---------------------------set_edges_for_java_call---------------------------
1574 // Connect a newly created call into the current JVMS.
1575 // A return value node (if any) is returned from set_edges_for_java_call.
1576 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1577 
1578   // Add the predefined inputs:
1579   call->init_req( TypeFunc::Control, control() );
1580   call->init_req( TypeFunc::I_O    , i_o() );
1581   call->init_req( TypeFunc::Memory , reset_memory() );
1582   call->init_req( TypeFunc::FramePtr, frameptr() );
1583   call->init_req( TypeFunc::ReturnAdr, top() );
1584 
1585   add_safepoint_edges(call, must_throw);
1586 
1587   Node* xcall = _gvn.transform(call);
1588 
1589   if (xcall == top()) {
1590     set_control(top());
1591     return;
1592   }
1593   assert(xcall == call, "call identity is stable");
1594 
1595   // Re-use the current map to produce the result.
1596 
1597   set_control(_gvn.transform(new (C, 1) ProjNode(call, TypeFunc::Control)));
1598   set_i_o(    _gvn.transform(new (C, 1) ProjNode(call, TypeFunc::I_O    , separate_io_proj)));
1599   set_all_memory_call(xcall, separate_io_proj);
1600 
1601   //return xcall;   // no need, caller already has it
1602 }
1603 
1604 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) {
1605   if (stopped())  return top();  // maybe the call folded up?
1606 
1607   // Capture the return value, if any.
1608   Node* ret;
1609   if (call->method() == NULL ||
1610       call->method()->return_type()->basic_type() == T_VOID)
1611         ret = top();
1612   else  ret = _gvn.transform(new (C, 1) ProjNode(call, TypeFunc::Parms));
1613 
1614   // Note:  Since any out-of-line call can produce an exception,
1615   // we always insert an I_O projection from the call into the result.
1616 
1617   make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj);
1618 
1619   if (separate_io_proj) {
1620     // The caller requested separate projections be used by the fall
1621     // through and exceptional paths, so replace the projections for
1622     // the fall through path.
1623     set_i_o(_gvn.transform( new (C, 1) ProjNode(call, TypeFunc::I_O) ));
1624     set_all_memory(_gvn.transform( new (C, 1) ProjNode(call, TypeFunc::Memory) ));
1625   }
1626   return ret;
1627 }
1628 
1629 //--------------------set_predefined_input_for_runtime_call--------------------
1630 // Reading and setting the memory state is way conservative here.
1631 // The real problem is that I am not doing real Type analysis on memory,
1632 // so I cannot distinguish card mark stores from other stores.  Across a GC
1633 // point the Store Barrier and the card mark memory has to agree.  I cannot
1634 // have a card mark store and its barrier split across the GC point from
1635 // either above or below.  Here I get that to happen by reading ALL of memory.
1636 // A better answer would be to separate out card marks from other memory.
1637 // For now, return the input memory state, so that it can be reused
1638 // after the call, if this call has restricted memory effects.
1639 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) {
1640   // Set fixed predefined input arguments
1641   Node* memory = reset_memory();
1642   call->init_req( TypeFunc::Control,   control()  );
1643   call->init_req( TypeFunc::I_O,       top()      ); // does no i/o
1644   call->init_req( TypeFunc::Memory,    memory     ); // may gc ptrs
1645   call->init_req( TypeFunc::FramePtr,  frameptr() );
1646   call->init_req( TypeFunc::ReturnAdr, top()      );
1647   return memory;
1648 }
1649 
1650 //-------------------set_predefined_output_for_runtime_call--------------------
1651 // Set control and memory (not i_o) from the call.
1652 // If keep_mem is not NULL, use it for the output state,
1653 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1654 // If hook_mem is NULL, this call produces no memory effects at all.
1655 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1656 // then only that memory slice is taken from the call.
1657 // In the last case, we must put an appropriate memory barrier before
1658 // the call, so as to create the correct anti-dependencies on loads
1659 // preceding the call.
1660 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1661                                                       Node* keep_mem,
1662                                                       const TypePtr* hook_mem) {
1663   // no i/o
1664   set_control(_gvn.transform( new (C, 1) ProjNode(call,TypeFunc::Control) ));
1665   if (keep_mem) {
1666     // First clone the existing memory state
1667     set_all_memory(keep_mem);
1668     if (hook_mem != NULL) {
1669       // Make memory for the call
1670       Node* mem = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::Memory) );
1671       // Set the RawPtr memory state only.  This covers all the heap top/GC stuff
1672       // We also use hook_mem to extract specific effects from arraycopy stubs.
1673       set_memory(mem, hook_mem);
1674     }
1675     // ...else the call has NO memory effects.
1676 
1677     // Make sure the call advertises its memory effects precisely.
1678     // This lets us build accurate anti-dependences in gcm.cpp.
1679     assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1680            "call node must be constructed correctly");
1681   } else {
1682     assert(hook_mem == NULL, "");
1683     // This is not a "slow path" call; all memory comes from the call.
1684     set_all_memory_call(call);
1685   }
1686 }
1687 
1688 
1689 // Replace the call with the current state of the kit.
1690 void GraphKit::replace_call(CallNode* call, Node* result) {
1691   JVMState* ejvms = NULL;
1692   if (has_exceptions()) {
1693     ejvms = transfer_exceptions_into_jvms();
1694   }
1695 
1696   SafePointNode* final_state = stop();
1697 
1698   // Find all the needed outputs of this call
1699   CallProjections callprojs;
1700   call->extract_projections(&callprojs, true);
1701 
1702   // Replace all the old call edges with the edges from the inlining result
1703   C->gvn_replace_by(callprojs.fallthrough_catchproj, final_state->in(TypeFunc::Control));
1704   C->gvn_replace_by(callprojs.fallthrough_memproj,   final_state->in(TypeFunc::Memory));
1705   C->gvn_replace_by(callprojs.fallthrough_ioproj,    final_state->in(TypeFunc::I_O));
1706 
1707   // Replace the result with the new result if it exists and is used
1708   if (callprojs.resproj != NULL && result != NULL) {
1709     C->gvn_replace_by(callprojs.resproj, result);
1710   }
1711 
1712   if (ejvms == NULL) {
1713     // No exception edges to simply kill off those paths
1714     C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1715     C->gvn_replace_by(callprojs.catchall_memproj,   C->top());
1716     C->gvn_replace_by(callprojs.catchall_ioproj,    C->top());
1717   } else {
1718     GraphKit ekit(ejvms);
1719 
1720     // Load my combined exception state into the kit, with all phis transformed:
1721     SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1722 
1723     Node* ex_oop = ekit.use_exception_state(ex_map);
1724 
1725     C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1726     C->gvn_replace_by(callprojs.catchall_memproj,   ekit.reset_memory());
1727     C->gvn_replace_by(callprojs.catchall_ioproj,    ekit.i_o());
1728 
1729     // Replace the old exception object with the newly created one
1730     if (callprojs.exobj != NULL) {
1731       C->gvn_replace_by(callprojs.exobj, ex_oop);
1732     }
1733   }
1734 
1735   // Disconnect the call from the graph
1736   call->disconnect_inputs(NULL);
1737   C->gvn_replace_by(call, C->top());
1738 }
1739 
1740 
1741 //------------------------------increment_counter------------------------------
1742 // for statistics: increment a VM counter by 1
1743 
1744 void GraphKit::increment_counter(address counter_addr) {
1745   Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
1746   increment_counter(adr1);
1747 }
1748 
1749 void GraphKit::increment_counter(Node* counter_addr) {
1750   int adr_type = Compile::AliasIdxRaw;
1751   Node* cnt  = make_load(NULL, counter_addr, TypeInt::INT, T_INT, adr_type);
1752   Node* incr = _gvn.transform(new (C, 3) AddINode(cnt, _gvn.intcon(1)));
1753   store_to_memory( NULL, counter_addr, incr, T_INT, adr_type );
1754 }
1755 
1756 
1757 //------------------------------uncommon_trap----------------------------------
1758 // Bail out to the interpreter in mid-method.  Implemented by calling the
1759 // uncommon_trap blob.  This helper function inserts a runtime call with the
1760 // right debug info.
1761 void GraphKit::uncommon_trap(int trap_request,
1762                              ciKlass* klass, const char* comment,
1763                              bool must_throw,
1764                              bool keep_exact_action) {
1765   if (failing())  stop();
1766   if (stopped())  return; // trap reachable?
1767 
1768   // Note:  If ProfileTraps is true, and if a deopt. actually
1769   // occurs here, the runtime will make sure an MDO exists.  There is
1770   // no need to call method()->build_method_data() at this point.
1771 
1772 #ifdef ASSERT
1773   if (!must_throw) {
1774     // Make sure the stack has at least enough depth to execute
1775     // the current bytecode.
1776     int inputs, ignore;
1777     if (compute_stack_effects(inputs, ignore)) {
1778       assert(sp() >= inputs, "must have enough JVMS stack to execute");
1779       // It is a frequent error in library_call.cpp to issue an
1780       // uncommon trap with the _sp value already popped.
1781     }
1782   }
1783 #endif
1784 
1785   Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
1786   Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
1787 
1788   switch (action) {
1789   case Deoptimization::Action_maybe_recompile:
1790   case Deoptimization::Action_reinterpret:
1791     // Temporary fix for 6529811 to allow virtual calls to be sure they
1792     // get the chance to go from mono->bi->mega
1793     if (!keep_exact_action &&
1794         Deoptimization::trap_request_index(trap_request) < 0 &&
1795         too_many_recompiles(reason)) {
1796       // This BCI is causing too many recompilations.
1797       action = Deoptimization::Action_none;
1798       trap_request = Deoptimization::make_trap_request(reason, action);
1799     } else {
1800       C->set_trap_can_recompile(true);
1801     }
1802     break;
1803   case Deoptimization::Action_make_not_entrant:
1804     C->set_trap_can_recompile(true);
1805     break;
1806 #ifdef ASSERT
1807   case Deoptimization::Action_none:
1808   case Deoptimization::Action_make_not_compilable:
1809     break;
1810   default:
1811     assert(false, "bad action");
1812 #endif
1813   }
1814 
1815   if (TraceOptoParse) {
1816     char buf[100];
1817     tty->print_cr("Uncommon trap %s at bci:%d",
1818                   Deoptimization::format_trap_request(buf, sizeof(buf),
1819                                                       trap_request), bci());
1820   }
1821 
1822   CompileLog* log = C->log();
1823   if (log != NULL) {
1824     int kid = (klass == NULL)? -1: log->identify(klass);
1825     log->begin_elem("uncommon_trap bci='%d'", bci());
1826     char buf[100];
1827     log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
1828                                                           trap_request));
1829     if (kid >= 0)         log->print(" klass='%d'", kid);
1830     if (comment != NULL)  log->print(" comment='%s'", comment);
1831     log->end_elem();
1832   }
1833 
1834   // Make sure any guarding test views this path as very unlikely
1835   Node *i0 = control()->in(0);
1836   if (i0 != NULL && i0->is_If()) {        // Found a guarding if test?
1837     IfNode *iff = i0->as_If();
1838     float f = iff->_prob;   // Get prob
1839     if (control()->Opcode() == Op_IfTrue) {
1840       if (f > PROB_UNLIKELY_MAG(4))
1841         iff->_prob = PROB_MIN;
1842     } else {
1843       if (f < PROB_LIKELY_MAG(4))
1844         iff->_prob = PROB_MAX;
1845     }
1846   }
1847 
1848   // Clear out dead values from the debug info.
1849   kill_dead_locals();
1850 
1851   // Now insert the uncommon trap subroutine call
1852   address call_addr = SharedRuntime::uncommon_trap_blob()->instructions_begin();
1853   const TypePtr* no_memory_effects = NULL;
1854   // Pass the index of the class to be loaded
1855   Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
1856                                  (must_throw ? RC_MUST_THROW : 0),
1857                                  OptoRuntime::uncommon_trap_Type(),
1858                                  call_addr, "uncommon_trap", no_memory_effects,
1859                                  intcon(trap_request));
1860   assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
1861          "must extract request correctly from the graph");
1862   assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
1863 
1864   call->set_req(TypeFunc::ReturnAdr, returnadr());
1865   // The debug info is the only real input to this call.
1866 
1867   // Halt-and-catch fire here.  The above call should never return!
1868   HaltNode* halt = new(C, TypeFunc::Parms) HaltNode(control(), frameptr());
1869   _gvn.set_type_bottom(halt);
1870   root()->add_req(halt);
1871 
1872   stop_and_kill_map();
1873 }
1874 
1875 
1876 //--------------------------just_allocated_object------------------------------
1877 // Report the object that was just allocated.
1878 // It must be the case that there are no intervening safepoints.
1879 // We use this to determine if an object is so "fresh" that
1880 // it does not require card marks.
1881 Node* GraphKit::just_allocated_object(Node* current_control) {
1882   if (C->recent_alloc_ctl() == current_control)
1883     return C->recent_alloc_obj();
1884   return NULL;
1885 }
1886 
1887 
1888 void GraphKit::round_double_arguments(ciMethod* dest_method) {
1889   // (Note:  TypeFunc::make has a cache that makes this fast.)
1890   const TypeFunc* tf    = TypeFunc::make(dest_method);
1891   int             nargs = tf->_domain->_cnt - TypeFunc::Parms;
1892   for (int j = 0; j < nargs; j++) {
1893     const Type *targ = tf->_domain->field_at(j + TypeFunc::Parms);
1894     if( targ->basic_type() == T_DOUBLE ) {
1895       // If any parameters are doubles, they must be rounded before
1896       // the call, dstore_rounding does gvn.transform
1897       Node *arg = argument(j);
1898       arg = dstore_rounding(arg);
1899       set_argument(j, arg);
1900     }
1901   }
1902 }
1903 
1904 void GraphKit::round_double_result(ciMethod* dest_method) {
1905   // A non-strict method may return a double value which has an extended
1906   // exponent, but this must not be visible in a caller which is 'strict'
1907   // If a strict caller invokes a non-strict callee, round a double result
1908 
1909   BasicType result_type = dest_method->return_type()->basic_type();
1910   assert( method() != NULL, "must have caller context");
1911   if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) {
1912     // Destination method's return value is on top of stack
1913     // dstore_rounding() does gvn.transform
1914     Node *result = pop_pair();
1915     result = dstore_rounding(result);
1916     push_pair(result);
1917   }
1918 }
1919 
1920 // rounding for strict float precision conformance
1921 Node* GraphKit::precision_rounding(Node* n) {
1922   return UseStrictFP && _method->flags().is_strict()
1923     && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding
1924     ? _gvn.transform( new (C, 2) RoundFloatNode(0, n) )
1925     : n;
1926 }
1927 
1928 // rounding for strict double precision conformance
1929 Node* GraphKit::dprecision_rounding(Node *n) {
1930   return UseStrictFP && _method->flags().is_strict()
1931     && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding
1932     ? _gvn.transform( new (C, 2) RoundDoubleNode(0, n) )
1933     : n;
1934 }
1935 
1936 // rounding for non-strict double stores
1937 Node* GraphKit::dstore_rounding(Node* n) {
1938   return Matcher::strict_fp_requires_explicit_rounding
1939     && UseSSE <= 1
1940     ? _gvn.transform( new (C, 2) RoundDoubleNode(0, n) )
1941     : n;
1942 }
1943 
1944 //=============================================================================
1945 // Generate a fast path/slow path idiom.  Graph looks like:
1946 // [foo] indicates that 'foo' is a parameter
1947 //
1948 //              [in]     NULL
1949 //                 \    /
1950 //                  CmpP
1951 //                  Bool ne
1952 //                   If
1953 //                  /  \
1954 //              True    False-<2>
1955 //              / |
1956 //             /  cast_not_null
1957 //           Load  |    |   ^
1958 //        [fast_test]   |   |
1959 // gvn to   opt_test    |   |
1960 //          /    \      |  <1>
1961 //      True     False  |
1962 //        |         \\  |
1963 //   [slow_call]     \[fast_result]
1964 //    Ctl   Val       \      \
1965 //     |               \      \
1966 //    Catch       <1>   \      \
1967 //   /    \        ^     \      \
1968 //  Ex    No_Ex    |      \      \
1969 //  |       \   \  |       \ <2>  \
1970 //  ...      \  [slow_res] |  |    \   [null_result]
1971 //            \         \--+--+---  |  |
1972 //             \           | /    \ | /
1973 //              --------Region     Phi
1974 //
1975 //=============================================================================
1976 // Code is structured as a series of driver functions all called 'do_XXX' that
1977 // call a set of helper functions.  Helper functions first, then drivers.
1978 
1979 //------------------------------null_check_oop---------------------------------
1980 // Null check oop.  Set null-path control into Region in slot 3.
1981 // Make a cast-not-nullness use the other not-null control.  Return cast.
1982 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
1983                                bool never_see_null) {
1984   // Initial NULL check taken path
1985   (*null_control) = top();
1986   Node* cast = null_check_common(value, T_OBJECT, false, null_control);
1987 
1988   // Generate uncommon_trap:
1989   if (never_see_null && (*null_control) != top()) {
1990     // If we see an unexpected null at a check-cast we record it and force a
1991     // recompile; the offending check-cast will be compiled to handle NULLs.
1992     // If we see more than one offending BCI, then all checkcasts in the
1993     // method will be compiled to handle NULLs.
1994     PreserveJVMState pjvms(this);
1995     set_control(*null_control);
1996     replace_in_map(value, null());
1997     uncommon_trap(Deoptimization::Reason_null_check,
1998                   Deoptimization::Action_make_not_entrant);
1999     (*null_control) = top();    // NULL path is dead
2000   }
2001 
2002   // Cast away null-ness on the result
2003   return cast;
2004 }
2005 
2006 //------------------------------opt_iff----------------------------------------
2007 // Optimize the fast-check IfNode.  Set the fast-path region slot 2.
2008 // Return slow-path control.
2009 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2010   IfNode *opt_iff = _gvn.transform(iff)->as_If();
2011 
2012   // Fast path taken; set region slot 2
2013   Node *fast_taken = _gvn.transform( new (C, 1) IfFalseNode(opt_iff) );
2014   region->init_req(2,fast_taken); // Capture fast-control
2015 
2016   // Fast path not-taken, i.e. slow path
2017   Node *slow_taken = _gvn.transform( new (C, 1) IfTrueNode(opt_iff) );
2018   return slow_taken;
2019 }
2020 
2021 //-----------------------------make_runtime_call-------------------------------
2022 Node* GraphKit::make_runtime_call(int flags,
2023                                   const TypeFunc* call_type, address call_addr,
2024                                   const char* call_name,
2025                                   const TypePtr* adr_type,
2026                                   // The following parms are all optional.
2027                                   // The first NULL ends the list.
2028                                   Node* parm0, Node* parm1,
2029                                   Node* parm2, Node* parm3,
2030                                   Node* parm4, Node* parm5,
2031                                   Node* parm6, Node* parm7) {
2032   // Slow-path call
2033   int size = call_type->domain()->cnt();
2034   bool is_leaf = !(flags & RC_NO_LEAF);
2035   bool has_io  = (!is_leaf && !(flags & RC_NO_IO));
2036   if (call_name == NULL) {
2037     assert(!is_leaf, "must supply name for leaf");
2038     call_name = OptoRuntime::stub_name(call_addr);
2039   }
2040   CallNode* call;
2041   if (!is_leaf) {
2042     call = new(C, size) CallStaticJavaNode(call_type, call_addr, call_name,
2043                                            bci(), adr_type);
2044   } else if (flags & RC_NO_FP) {
2045     call = new(C, size) CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2046   } else {
2047     call = new(C, size) CallLeafNode(call_type, call_addr, call_name, adr_type);
2048   }
2049 
2050   // The following is similar to set_edges_for_java_call,
2051   // except that the memory effects of the call are restricted to AliasIdxRaw.
2052 
2053   // Slow path call has no side-effects, uses few values
2054   bool wide_in  = !(flags & RC_NARROW_MEM);
2055   bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2056 
2057   Node* prev_mem = NULL;
2058   if (wide_in) {
2059     prev_mem = set_predefined_input_for_runtime_call(call);
2060   } else {
2061     assert(!wide_out, "narrow in => narrow out");
2062     Node* narrow_mem = memory(adr_type);
2063     prev_mem = reset_memory();
2064     map()->set_memory(narrow_mem);
2065     set_predefined_input_for_runtime_call(call);
2066   }
2067 
2068   // Hook each parm in order.  Stop looking at the first NULL.
2069   if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0);
2070   if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1);
2071   if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2);
2072   if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3);
2073   if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4);
2074   if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5);
2075   if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6);
2076   if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7);
2077     /* close each nested if ===> */  } } } } } } } }
2078   assert(call->in(call->req()-1) != NULL, "must initialize all parms");
2079 
2080   if (!is_leaf) {
2081     // Non-leaves can block and take safepoints:
2082     add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2083   }
2084   // Non-leaves can throw exceptions:
2085   if (has_io) {
2086     call->set_req(TypeFunc::I_O, i_o());
2087   }
2088 
2089   if (flags & RC_UNCOMMON) {
2090     // Set the count to a tiny probability.  Cf. Estimate_Block_Frequency.
2091     // (An "if" probability corresponds roughly to an unconditional count.
2092     // Sort of.)
2093     call->set_cnt(PROB_UNLIKELY_MAG(4));
2094   }
2095 
2096   Node* c = _gvn.transform(call);
2097   assert(c == call, "cannot disappear");
2098 
2099   if (wide_out) {
2100     // Slow path call has full side-effects.
2101     set_predefined_output_for_runtime_call(call);
2102   } else {
2103     // Slow path call has few side-effects, and/or sets few values.
2104     set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2105   }
2106 
2107   if (has_io) {
2108     set_i_o(_gvn.transform(new (C, 1) ProjNode(call, TypeFunc::I_O)));
2109   }
2110   return call;
2111 
2112 }
2113 
2114 //------------------------------merge_memory-----------------------------------
2115 // Merge memory from one path into the current memory state.
2116 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2117   for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2118     Node* old_slice = mms.force_memory();
2119     Node* new_slice = mms.memory2();
2120     if (old_slice != new_slice) {
2121       PhiNode* phi;
2122       if (new_slice->is_Phi() && new_slice->as_Phi()->region() == region) {
2123         phi = new_slice->as_Phi();
2124         #ifdef ASSERT
2125         if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region)
2126           old_slice = old_slice->in(new_path);
2127         // Caller is responsible for ensuring that any pre-existing
2128         // phis are already aware of old memory.
2129         int old_path = (new_path > 1) ? 1 : 2;  // choose old_path != new_path
2130         assert(phi->in(old_path) == old_slice, "pre-existing phis OK");
2131         #endif
2132         mms.set_memory(phi);
2133       } else {
2134         phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2135         _gvn.set_type(phi, Type::MEMORY);
2136         phi->set_req(new_path, new_slice);
2137         mms.set_memory(_gvn.transform(phi));  // assume it is complete
2138       }
2139     }
2140   }
2141 }
2142 
2143 //------------------------------make_slow_call_ex------------------------------
2144 // Make the exception handler hookups for the slow call
2145 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj) {
2146   if (stopped())  return;
2147 
2148   // Make a catch node with just two handlers:  fall-through and catch-all
2149   Node* i_o  = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2150   Node* catc = _gvn.transform( new (C, 2) CatchNode(control(), i_o, 2) );
2151   Node* norm = _gvn.transform( new (C, 1) CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) );
2152   Node* excp = _gvn.transform( new (C, 1) CatchProjNode(catc, CatchProjNode::catch_all_index,    CatchProjNode::no_handler_bci) );
2153 
2154   { PreserveJVMState pjvms(this);
2155     set_control(excp);
2156     set_i_o(i_o);
2157 
2158     if (excp != top()) {
2159       // Create an exception state also.
2160       // Use an exact type if the caller has specified a specific exception.
2161       const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2162       Node*       ex_oop  = new (C, 2) CreateExNode(ex_type, control(), i_o);
2163       add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2164     }
2165   }
2166 
2167   // Get the no-exception control from the CatchNode.
2168   set_control(norm);
2169 }
2170 
2171 
2172 //-------------------------------gen_subtype_check-----------------------------
2173 // Generate a subtyping check.  Takes as input the subtype and supertype.
2174 // Returns 2 values: sets the default control() to the true path and returns
2175 // the false path.  Only reads invariant memory; sets no (visible) memory.
2176 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2177 // but that's not exposed to the optimizer.  This call also doesn't take in an
2178 // Object; if you wish to check an Object you need to load the Object's class
2179 // prior to coming here.
2180 Node* GraphKit::gen_subtype_check(Node* subklass, Node* superklass) {
2181   // Fast check for identical types, perhaps identical constants.
2182   // The types can even be identical non-constants, in cases
2183   // involving Array.newInstance, Object.clone, etc.
2184   if (subklass == superklass)
2185     return top();             // false path is dead; no test needed.
2186 
2187   if (_gvn.type(superklass)->singleton()) {
2188     ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2189     ciKlass* subk   = _gvn.type(subklass)->is_klassptr()->klass();
2190 
2191     // In the common case of an exact superklass, try to fold up the
2192     // test before generating code.  You may ask, why not just generate
2193     // the code and then let it fold up?  The answer is that the generated
2194     // code will necessarily include null checks, which do not always
2195     // completely fold away.  If they are also needless, then they turn
2196     // into a performance loss.  Example:
2197     //    Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2198     // Here, the type of 'fa' is often exact, so the store check
2199     // of fa[1]=x will fold up, without testing the nullness of x.
2200     switch (static_subtype_check(superk, subk)) {
2201     case SSC_always_false:
2202       {
2203         Node* always_fail = control();
2204         set_control(top());
2205         return always_fail;
2206       }
2207     case SSC_always_true:
2208       return top();
2209     case SSC_easy_test:
2210       {
2211         // Just do a direct pointer compare and be done.
2212         Node* cmp = _gvn.transform( new(C, 3) CmpPNode(subklass, superklass) );
2213         Node* bol = _gvn.transform( new(C, 2) BoolNode(cmp, BoolTest::eq) );
2214         IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN);
2215         set_control( _gvn.transform( new(C, 1) IfTrueNode (iff) ) );
2216         return       _gvn.transform( new(C, 1) IfFalseNode(iff) );
2217       }
2218     case SSC_full_test:
2219       break;
2220     default:
2221       ShouldNotReachHere();
2222     }
2223   }
2224 
2225   // %%% Possible further optimization:  Even if the superklass is not exact,
2226   // if the subklass is the unique subtype of the superklass, the check
2227   // will always succeed.  We could leave a dependency behind to ensure this.
2228 
2229   // First load the super-klass's check-offset
2230   Node *p1 = basic_plus_adr( superklass, superklass, sizeof(oopDesc) + Klass::super_check_offset_offset_in_bytes() );
2231   Node *chk_off = _gvn.transform( new (C, 3) LoadINode( NULL, memory(p1), p1, _gvn.type(p1)->is_ptr() ) );
2232   int cacheoff_con = sizeof(oopDesc) + Klass::secondary_super_cache_offset_in_bytes();
2233   bool might_be_cache = (find_int_con(chk_off, cacheoff_con) == cacheoff_con);
2234 
2235   // Load from the sub-klass's super-class display list, or a 1-word cache of
2236   // the secondary superclass list, or a failing value with a sentinel offset
2237   // if the super-klass is an interface or exceptionally deep in the Java
2238   // hierarchy and we have to scan the secondary superclass list the hard way.
2239   // Worst-case type is a little odd: NULL is allowed as a result (usually
2240   // klass loads can never produce a NULL).
2241   Node *chk_off_X = ConvI2X(chk_off);
2242   Node *p2 = _gvn.transform( new (C, 4) AddPNode(subklass,subklass,chk_off_X) );
2243   // For some types like interfaces the following loadKlass is from a 1-word
2244   // cache which is mutable so can't use immutable memory.  Other
2245   // types load from the super-class display table which is immutable.
2246   Node *kmem = might_be_cache ? memory(p2) : immutable_memory();
2247   Node *nkls = _gvn.transform( LoadKlassNode::make( _gvn, kmem, p2, _gvn.type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL ) );
2248 
2249   // Compile speed common case: ARE a subtype and we canNOT fail
2250   if( superklass == nkls )
2251     return top();             // false path is dead; no test needed.
2252 
2253   // See if we get an immediate positive hit.  Happens roughly 83% of the
2254   // time.  Test to see if the value loaded just previously from the subklass
2255   // is exactly the superklass.
2256   Node *cmp1 = _gvn.transform( new (C, 3) CmpPNode( superklass, nkls ) );
2257   Node *bol1 = _gvn.transform( new (C, 2) BoolNode( cmp1, BoolTest::eq ) );
2258   IfNode *iff1 = create_and_xform_if( control(), bol1, PROB_LIKELY(0.83f), COUNT_UNKNOWN );
2259   Node *iftrue1 = _gvn.transform( new (C, 1) IfTrueNode ( iff1 ) );
2260   set_control(    _gvn.transform( new (C, 1) IfFalseNode( iff1 ) ) );
2261 
2262   // Compile speed common case: Check for being deterministic right now.  If
2263   // chk_off is a constant and not equal to cacheoff then we are NOT a
2264   // subklass.  In this case we need exactly the 1 test above and we can
2265   // return those results immediately.
2266   if (!might_be_cache) {
2267     Node* not_subtype_ctrl = control();
2268     set_control(iftrue1); // We need exactly the 1 test above
2269     return not_subtype_ctrl;
2270   }
2271 
2272   // Gather the various success & failures here
2273   RegionNode *r_ok_subtype = new (C, 4) RegionNode(4);
2274   record_for_igvn(r_ok_subtype);
2275   RegionNode *r_not_subtype = new (C, 3) RegionNode(3);
2276   record_for_igvn(r_not_subtype);
2277 
2278   r_ok_subtype->init_req(1, iftrue1);
2279 
2280   // Check for immediate negative hit.  Happens roughly 11% of the time (which
2281   // is roughly 63% of the remaining cases).  Test to see if the loaded
2282   // check-offset points into the subklass display list or the 1-element
2283   // cache.  If it points to the display (and NOT the cache) and the display
2284   // missed then it's not a subtype.
2285   Node *cacheoff = _gvn.intcon(cacheoff_con);
2286   Node *cmp2 = _gvn.transform( new (C, 3) CmpINode( chk_off, cacheoff ) );
2287   Node *bol2 = _gvn.transform( new (C, 2) BoolNode( cmp2, BoolTest::ne ) );
2288   IfNode *iff2 = create_and_xform_if( control(), bol2, PROB_LIKELY(0.63f), COUNT_UNKNOWN );
2289   r_not_subtype->init_req(1, _gvn.transform( new (C, 1) IfTrueNode (iff2) ) );
2290   set_control(                _gvn.transform( new (C, 1) IfFalseNode(iff2) ) );
2291 
2292   // Check for self.  Very rare to get here, but it is taken 1/3 the time.
2293   // No performance impact (too rare) but allows sharing of secondary arrays
2294   // which has some footprint reduction.
2295   Node *cmp3 = _gvn.transform( new (C, 3) CmpPNode( subklass, superklass ) );
2296   Node *bol3 = _gvn.transform( new (C, 2) BoolNode( cmp3, BoolTest::eq ) );
2297   IfNode *iff3 = create_and_xform_if( control(), bol3, PROB_LIKELY(0.36f), COUNT_UNKNOWN );
2298   r_ok_subtype->init_req(2, _gvn.transform( new (C, 1) IfTrueNode ( iff3 ) ) );
2299   set_control(               _gvn.transform( new (C, 1) IfFalseNode( iff3 ) ) );
2300 
2301   // -- Roads not taken here: --
2302   // We could also have chosen to perform the self-check at the beginning
2303   // of this code sequence, as the assembler does.  This would not pay off
2304   // the same way, since the optimizer, unlike the assembler, can perform
2305   // static type analysis to fold away many successful self-checks.
2306   // Non-foldable self checks work better here in second position, because
2307   // the initial primary superclass check subsumes a self-check for most
2308   // types.  An exception would be a secondary type like array-of-interface,
2309   // which does not appear in its own primary supertype display.
2310   // Finally, we could have chosen to move the self-check into the
2311   // PartialSubtypeCheckNode, and from there out-of-line in a platform
2312   // dependent manner.  But it is worthwhile to have the check here,
2313   // where it can be perhaps be optimized.  The cost in code space is
2314   // small (register compare, branch).
2315 
2316   // Now do a linear scan of the secondary super-klass array.  Again, no real
2317   // performance impact (too rare) but it's gotta be done.
2318   // Since the code is rarely used, there is no penalty for moving it
2319   // out of line, and it can only improve I-cache density.
2320   // The decision to inline or out-of-line this final check is platform
2321   // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2322   Node* psc = _gvn.transform(
2323     new (C, 3) PartialSubtypeCheckNode(control(), subklass, superklass) );
2324 
2325   Node *cmp4 = _gvn.transform( new (C, 3) CmpPNode( psc, null() ) );
2326   Node *bol4 = _gvn.transform( new (C, 2) BoolNode( cmp4, BoolTest::ne ) );
2327   IfNode *iff4 = create_and_xform_if( control(), bol4, PROB_FAIR, COUNT_UNKNOWN );
2328   r_not_subtype->init_req(2, _gvn.transform( new (C, 1) IfTrueNode (iff4) ) );
2329   r_ok_subtype ->init_req(3, _gvn.transform( new (C, 1) IfFalseNode(iff4) ) );
2330 
2331   // Return false path; set default control to true path.
2332   set_control( _gvn.transform(r_ok_subtype) );
2333   return _gvn.transform(r_not_subtype);
2334 }
2335 
2336 //----------------------------static_subtype_check-----------------------------
2337 // Shortcut important common cases when superklass is exact:
2338 // (0) superklass is java.lang.Object (can occur in reflective code)
2339 // (1) subklass is already limited to a subtype of superklass => always ok
2340 // (2) subklass does not overlap with superklass => always fail
2341 // (3) superklass has NO subtypes and we can check with a simple compare.
2342 int GraphKit::static_subtype_check(ciKlass* superk, ciKlass* subk) {
2343   if (StressReflectiveCode) {
2344     return SSC_full_test;       // Let caller generate the general case.
2345   }
2346 
2347   if (superk == env()->Object_klass()) {
2348     return SSC_always_true;     // (0) this test cannot fail
2349   }
2350 
2351   ciType* superelem = superk;
2352   if (superelem->is_array_klass())
2353     superelem = superelem->as_array_klass()->base_element_type();
2354 
2355   if (!subk->is_interface()) {  // cannot trust static interface types yet
2356     if (subk->is_subtype_of(superk)) {
2357       return SSC_always_true;   // (1) false path dead; no dynamic test needed
2358     }
2359     if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
2360         !superk->is_subtype_of(subk)) {
2361       return SSC_always_false;
2362     }
2363   }
2364 
2365   // If casting to an instance klass, it must have no subtypes
2366   if (superk->is_interface()) {
2367     // Cannot trust interfaces yet.
2368     // %%% S.B. superk->nof_implementors() == 1
2369   } else if (superelem->is_instance_klass()) {
2370     ciInstanceKlass* ik = superelem->as_instance_klass();
2371     if (!ik->has_subklass() && !ik->is_interface()) {
2372       if (!ik->is_final()) {
2373         // Add a dependency if there is a chance of a later subclass.
2374         C->dependencies()->assert_leaf_type(ik);
2375       }
2376       return SSC_easy_test;     // (3) caller can do a simple ptr comparison
2377     }
2378   } else {
2379     // A primitive array type has no subtypes.
2380     return SSC_easy_test;       // (3) caller can do a simple ptr comparison
2381   }
2382 
2383   return SSC_full_test;
2384 }
2385 
2386 // Profile-driven exact type check:
2387 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2388                                     float prob,
2389                                     Node* *casted_receiver) {
2390   const TypeKlassPtr* tklass = TypeKlassPtr::make(klass);
2391   Node* recv_klass = load_object_klass(receiver);
2392   Node* want_klass = makecon(tklass);
2393   Node* cmp = _gvn.transform( new(C, 3) CmpPNode(recv_klass, want_klass) );
2394   Node* bol = _gvn.transform( new(C, 2) BoolNode(cmp, BoolTest::eq) );
2395   IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2396   set_control( _gvn.transform( new(C, 1) IfTrueNode (iff) ));
2397   Node* fail = _gvn.transform( new(C, 1) IfFalseNode(iff) );
2398 
2399   const TypeOopPtr* recv_xtype = tklass->as_instance_type();
2400   assert(recv_xtype->klass_is_exact(), "");
2401 
2402   // Subsume downstream occurrences of receiver with a cast to
2403   // recv_xtype, since now we know what the type will be.
2404   Node* cast = new(C, 2) CheckCastPPNode(control(), receiver, recv_xtype);
2405   (*casted_receiver) = _gvn.transform(cast);
2406   // (User must make the replace_in_map call.)
2407 
2408   return fail;
2409 }
2410 
2411 
2412 //-------------------------------gen_instanceof--------------------------------
2413 // Generate an instance-of idiom.  Used by both the instance-of bytecode
2414 // and the reflective instance-of call.
2415 Node* GraphKit::gen_instanceof( Node *subobj, Node* superklass ) {
2416   C->set_has_split_ifs(true); // Has chance for split-if optimization
2417   assert( !stopped(), "dead parse path should be checked in callers" );
2418   assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
2419          "must check for not-null not-dead klass in callers");
2420 
2421   // Make the merge point
2422   enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
2423   RegionNode* region = new(C, PATH_LIMIT) RegionNode(PATH_LIMIT);
2424   Node*       phi    = new(C, PATH_LIMIT) PhiNode(region, TypeInt::BOOL);
2425   C->set_has_split_ifs(true); // Has chance for split-if optimization
2426 
2427   // Null check; get casted pointer; set region slot 3
2428   Node* null_ctl = top();
2429   Node* not_null_obj = null_check_oop(subobj, &null_ctl);
2430 
2431   // If not_null_obj is dead, only null-path is taken
2432   if (stopped()) {              // Doing instance-of on a NULL?
2433     set_control(null_ctl);
2434     return intcon(0);
2435   }
2436   region->init_req(_null_path, null_ctl);
2437   phi   ->init_req(_null_path, intcon(0)); // Set null path value
2438 
2439   // Load the object's klass
2440   Node* obj_klass = load_object_klass(not_null_obj);
2441 
2442   // Generate the subtype check
2443   Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass);
2444 
2445   // Plug in the success path to the general merge in slot 1.
2446   region->init_req(_obj_path, control());
2447   phi   ->init_req(_obj_path, intcon(1));
2448 
2449   // Plug in the failing path to the general merge in slot 2.
2450   region->init_req(_fail_path, not_subtype_ctrl);
2451   phi   ->init_req(_fail_path, intcon(0));
2452 
2453   // Return final merged results
2454   set_control( _gvn.transform(region) );
2455   record_for_igvn(region);
2456   return _gvn.transform(phi);
2457 }
2458 
2459 //-------------------------------gen_checkcast---------------------------------
2460 // Generate a checkcast idiom.  Used by both the checkcast bytecode and the
2461 // array store bytecode.  Stack must be as-if BEFORE doing the bytecode so the
2462 // uncommon-trap paths work.  Adjust stack after this call.
2463 // If failure_control is supplied and not null, it is filled in with
2464 // the control edge for the cast failure.  Otherwise, an appropriate
2465 // uncommon trap or exception is thrown.
2466 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
2467                               Node* *failure_control) {
2468   kill_dead_locals();           // Benefit all the uncommon traps
2469   const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr();
2470   const Type *toop = TypeOopPtr::make_from_klass(tk->klass());
2471 
2472   // Fast cutout:  Check the case that the cast is vacuously true.
2473   // This detects the common cases where the test will short-circuit
2474   // away completely.  We do this before we perform the null check,
2475   // because if the test is going to turn into zero code, we don't
2476   // want a residual null check left around.  (Causes a slowdown,
2477   // for example, in some objArray manipulations, such as a[i]=a[j].)
2478   if (tk->singleton()) {
2479     const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
2480     if (objtp != NULL && objtp->klass() != NULL) {
2481       switch (static_subtype_check(tk->klass(), objtp->klass())) {
2482       case SSC_always_true:
2483         return obj;
2484       case SSC_always_false:
2485         // It needs a null check because a null will *pass* the cast check.
2486         // A non-null value will always produce an exception.
2487         return do_null_assert(obj, T_OBJECT);
2488       }
2489     }
2490   }
2491 
2492   ciProfileData* data = NULL;
2493   if (failure_control == NULL) {        // use MDO in regular case only
2494     assert(java_bc() == Bytecodes::_aastore ||
2495            java_bc() == Bytecodes::_checkcast,
2496            "interpreter profiles type checks only for these BCs");
2497     data = method()->method_data()->bci_to_data(bci());
2498   }
2499 
2500   // Make the merge point
2501   enum { _obj_path = 1, _null_path, PATH_LIMIT };
2502   RegionNode* region = new (C, PATH_LIMIT) RegionNode(PATH_LIMIT);
2503   Node*       phi    = new (C, PATH_LIMIT) PhiNode(region, toop);
2504   C->set_has_split_ifs(true); // Has chance for split-if optimization
2505 
2506   // Use null-cast information if it is available
2507   bool never_see_null = false;
2508   // If we see an unexpected null at a check-cast we record it and force a
2509   // recompile; the offending check-cast will be compiled to handle NULLs.
2510   // If we see several offending BCIs, then all checkcasts in the
2511   // method will be compiled to handle NULLs.
2512   if (UncommonNullCast            // Cutout for this technique
2513       && failure_control == NULL  // regular case
2514       && obj != null()            // And not the -Xcomp stupid case?
2515       && !too_many_traps(Deoptimization::Reason_null_check)) {
2516     // Finally, check the "null_seen" bit from the interpreter.
2517     if (data == NULL || !data->as_BitData()->null_seen()) {
2518       never_see_null = true;
2519     }
2520   }
2521 
2522   // Null check; get casted pointer; set region slot 3
2523   Node* null_ctl = top();
2524   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null);
2525 
2526   // If not_null_obj is dead, only null-path is taken
2527   if (stopped()) {              // Doing instance-of on a NULL?
2528     set_control(null_ctl);
2529     return null();
2530   }
2531   region->init_req(_null_path, null_ctl);
2532   phi   ->init_req(_null_path, null());  // Set null path value
2533 
2534   Node* cast_obj = NULL;        // the casted version of the object
2535 
2536   // If the profile has seen exactly one type, narrow to that type.
2537   // (The subsequent subtype check will always fold up.)
2538   if (UseTypeProfile && TypeProfileCasts && data != NULL &&
2539       // Counter has never been decremented (due to cast failure).
2540       // ...This is a reasonable thing to expect.  It is true of
2541       // all casts inserted by javac to implement generic types.
2542       data->as_CounterData()->count() >= 0 &&
2543       !too_many_traps(Deoptimization::Reason_class_check)) {
2544     // (No, this isn't a call, but it's enough like a virtual call
2545     // to use the same ciMethod accessor to get the profile info...)
2546     ciCallProfile profile = method()->call_profile_at_bci(bci());
2547     if (profile.count() >= 0 &&         // no cast failures here
2548         profile.has_receiver(0) &&
2549         profile.morphism() == 1) {
2550       ciKlass* exact_kls = profile.receiver(0);
2551       int ssc = static_subtype_check(tk->klass(), exact_kls);
2552       if (ssc == SSC_always_true) {
2553         // If we narrow the type to match what the type profile sees,
2554         // we can then remove the rest of the cast.
2555         // This is a win, even if the exact_kls is very specific,
2556         // because downstream operations, such as method calls,
2557         // will often benefit from the sharper type.
2558         Node* exact_obj = not_null_obj; // will get updated in place...
2559         Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
2560                                               &exact_obj);
2561         { PreserveJVMState pjvms(this);
2562           set_control(slow_ctl);
2563           uncommon_trap(Deoptimization::Reason_class_check,
2564                         Deoptimization::Action_maybe_recompile);
2565         }
2566         if (failure_control != NULL) // failure is now impossible
2567           (*failure_control) = top();
2568         replace_in_map(not_null_obj, exact_obj);
2569         // adjust the type of the phi to the exact klass:
2570         phi->raise_bottom_type(_gvn.type(exact_obj)->meet(TypePtr::NULL_PTR));
2571         cast_obj = exact_obj;
2572       }
2573       // assert(cast_obj != NULL)... except maybe the profile lied to us.
2574     }
2575   }
2576 
2577   if (cast_obj == NULL) {
2578     // Load the object's klass
2579     Node* obj_klass = load_object_klass(not_null_obj);
2580 
2581     // Generate the subtype check
2582     Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass );
2583 
2584     // Plug in success path into the merge
2585     cast_obj = _gvn.transform(new (C, 2) CheckCastPPNode(control(),
2586                                                          not_null_obj, toop));
2587     // Failure path ends in uncommon trap (or may be dead - failure impossible)
2588     if (failure_control == NULL) {
2589       if (not_subtype_ctrl != top()) { // If failure is possible
2590         PreserveJVMState pjvms(this);
2591         set_control(not_subtype_ctrl);
2592         builtin_throw(Deoptimization::Reason_class_check, obj_klass);
2593       }
2594     } else {
2595       (*failure_control) = not_subtype_ctrl;
2596     }
2597   }
2598 
2599   region->init_req(_obj_path, control());
2600   phi   ->init_req(_obj_path, cast_obj);
2601 
2602   // A merge of NULL or Casted-NotNull obj
2603   Node* res = _gvn.transform(phi);
2604 
2605   // Note I do NOT always 'replace_in_map(obj,result)' here.
2606   //  if( tk->klass()->can_be_primary_super()  )
2607     // This means that if I successfully store an Object into an array-of-String
2608     // I 'forget' that the Object is really now known to be a String.  I have to
2609     // do this because we don't have true union types for interfaces - if I store
2610     // a Baz into an array-of-Interface and then tell the optimizer it's an
2611     // Interface, I forget that it's also a Baz and cannot do Baz-like field
2612     // references to it.  FIX THIS WHEN UNION TYPES APPEAR!
2613   //  replace_in_map( obj, res );
2614 
2615   // Return final merged results
2616   set_control( _gvn.transform(region) );
2617   record_for_igvn(region);
2618   return res;
2619 }
2620 
2621 //------------------------------next_monitor-----------------------------------
2622 // What number should be given to the next monitor?
2623 int GraphKit::next_monitor() {
2624   int current = jvms()->monitor_depth()* C->sync_stack_slots();
2625   int next = current + C->sync_stack_slots();
2626   // Keep the toplevel high water mark current:
2627   if (C->fixed_slots() < next)  C->set_fixed_slots(next);
2628   return current;
2629 }
2630 
2631 //------------------------------insert_mem_bar---------------------------------
2632 // Memory barrier to avoid floating things around
2633 // The membar serves as a pinch point between both control and all memory slices.
2634 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
2635   MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
2636   mb->init_req(TypeFunc::Control, control());
2637   mb->init_req(TypeFunc::Memory,  reset_memory());
2638   Node* membar = _gvn.transform(mb);
2639   set_control(_gvn.transform(new (C, 1) ProjNode(membar,TypeFunc::Control) ));
2640   set_all_memory_call(membar);
2641   return membar;
2642 }
2643 
2644 //-------------------------insert_mem_bar_volatile----------------------------
2645 // Memory barrier to avoid floating things around
2646 // The membar serves as a pinch point between both control and memory(alias_idx).
2647 // If you want to make a pinch point on all memory slices, do not use this
2648 // function (even with AliasIdxBot); use insert_mem_bar() instead.
2649 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
2650   // When Parse::do_put_xxx updates a volatile field, it appends a series
2651   // of MemBarVolatile nodes, one for *each* volatile field alias category.
2652   // The first membar is on the same memory slice as the field store opcode.
2653   // This forces the membar to follow the store.  (Bug 6500685 broke this.)
2654   // All the other membars (for other volatile slices, including AliasIdxBot,
2655   // which stands for all unknown volatile slices) are control-dependent
2656   // on the first membar.  This prevents later volatile loads or stores
2657   // from sliding up past the just-emitted store.
2658 
2659   MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
2660   mb->set_req(TypeFunc::Control,control());
2661   if (alias_idx == Compile::AliasIdxBot) {
2662     mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
2663   } else {
2664     assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
2665     mb->set_req(TypeFunc::Memory, memory(alias_idx));
2666   }
2667   Node* membar = _gvn.transform(mb);
2668   set_control(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Control)));
2669   if (alias_idx == Compile::AliasIdxBot) {
2670     merged_memory()->set_base_memory(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Memory)));
2671   } else {
2672     set_memory(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Memory)),alias_idx);
2673   }
2674   return membar;
2675 }
2676 
2677 //------------------------------shared_lock------------------------------------
2678 // Emit locking code.
2679 FastLockNode* GraphKit::shared_lock(Node* obj) {
2680   // bci is either a monitorenter bc or InvocationEntryBci
2681   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
2682   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
2683 
2684   if( !GenerateSynchronizationCode )
2685     return NULL;                // Not locking things?
2686   if (stopped())                // Dead monitor?
2687     return NULL;
2688 
2689   assert(dead_locals_are_killed(), "should kill locals before sync. point");
2690 
2691   // Box the stack location
2692   Node* box = _gvn.transform(new (C, 1) BoxLockNode(next_monitor()));
2693   Node* mem = reset_memory();
2694 
2695   FastLockNode * flock = _gvn.transform(new (C, 3) FastLockNode(0, obj, box) )->as_FastLock();
2696   if (PrintPreciseBiasedLockingStatistics) {
2697     // Create the counters for this fast lock.
2698     flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci
2699   }
2700   // Add monitor to debug info for the slow path.  If we block inside the
2701   // slow path and de-opt, we need the monitor hanging around
2702   map()->push_monitor( flock );
2703 
2704   const TypeFunc *tf = LockNode::lock_type();
2705   LockNode *lock = new (C, tf->domain()->cnt()) LockNode(C, tf);
2706 
2707   lock->init_req( TypeFunc::Control, control() );
2708   lock->init_req( TypeFunc::Memory , mem );
2709   lock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
2710   lock->init_req( TypeFunc::FramePtr, frameptr() );
2711   lock->init_req( TypeFunc::ReturnAdr, top() );
2712 
2713   lock->init_req(TypeFunc::Parms + 0, obj);
2714   lock->init_req(TypeFunc::Parms + 1, box);
2715   lock->init_req(TypeFunc::Parms + 2, flock);
2716   add_safepoint_edges(lock);
2717 
2718   lock = _gvn.transform( lock )->as_Lock();
2719 
2720   // lock has no side-effects, sets few values
2721   set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
2722 
2723   insert_mem_bar(Op_MemBarAcquire);
2724 
2725   // Add this to the worklist so that the lock can be eliminated
2726   record_for_igvn(lock);
2727 
2728 #ifndef PRODUCT
2729   if (PrintLockStatistics) {
2730     // Update the counter for this lock.  Don't bother using an atomic
2731     // operation since we don't require absolute accuracy.
2732     lock->create_lock_counter(map()->jvms());
2733     int adr_type = Compile::AliasIdxRaw;
2734     Node* counter_addr = makecon(TypeRawPtr::make(lock->counter()->addr()));
2735     Node* cnt  = make_load(NULL, counter_addr, TypeInt::INT, T_INT, adr_type);
2736     Node* incr = _gvn.transform(new (C, 3) AddINode(cnt, _gvn.intcon(1)));
2737     store_to_memory(control(), counter_addr, incr, T_INT, adr_type);
2738   }
2739 #endif
2740 
2741   return flock;
2742 }
2743 
2744 
2745 //------------------------------shared_unlock----------------------------------
2746 // Emit unlocking code.
2747 void GraphKit::shared_unlock(Node* box, Node* obj) {
2748   // bci is either a monitorenter bc or InvocationEntryBci
2749   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
2750   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
2751 
2752   if( !GenerateSynchronizationCode )
2753     return;
2754   if (stopped()) {               // Dead monitor?
2755     map()->pop_monitor();        // Kill monitor from debug info
2756     return;
2757   }
2758 
2759   // Memory barrier to avoid floating things down past the locked region
2760   insert_mem_bar(Op_MemBarRelease);
2761 
2762   const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
2763   UnlockNode *unlock = new (C, tf->domain()->cnt()) UnlockNode(C, tf);
2764   uint raw_idx = Compile::AliasIdxRaw;
2765   unlock->init_req( TypeFunc::Control, control() );
2766   unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
2767   unlock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
2768   unlock->init_req( TypeFunc::FramePtr, frameptr() );
2769   unlock->init_req( TypeFunc::ReturnAdr, top() );
2770 
2771   unlock->init_req(TypeFunc::Parms + 0, obj);
2772   unlock->init_req(TypeFunc::Parms + 1, box);
2773   unlock = _gvn.transform(unlock)->as_Unlock();
2774 
2775   Node* mem = reset_memory();
2776 
2777   // unlock has no side-effects, sets few values
2778   set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
2779 
2780   // Kill monitor from debug info
2781   map()->pop_monitor( );
2782 }
2783 
2784 //-------------------------------get_layout_helper-----------------------------
2785 // If the given klass is a constant or known to be an array,
2786 // fetch the constant layout helper value into constant_value
2787 // and return (Node*)NULL.  Otherwise, load the non-constant
2788 // layout helper value, and return the node which represents it.
2789 // This two-faced routine is useful because allocation sites
2790 // almost always feature constant types.
2791 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
2792   const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr();
2793   if (!StressReflectiveCode && inst_klass != NULL) {
2794     ciKlass* klass = inst_klass->klass();
2795     bool    xklass = inst_klass->klass_is_exact();
2796     if (xklass || klass->is_array_klass()) {
2797       jint lhelper = klass->layout_helper();
2798       if (lhelper != Klass::_lh_neutral_value) {
2799         constant_value = lhelper;
2800         return (Node*) NULL;
2801       }
2802     }
2803   }
2804   constant_value = Klass::_lh_neutral_value;  // put in a known value
2805   Node* lhp = basic_plus_adr(klass_node, klass_node, Klass::layout_helper_offset_in_bytes() + sizeof(oopDesc));
2806   return make_load(NULL, lhp, TypeInt::INT, T_INT);
2807 }
2808 
2809 // We just put in an allocate/initialize with a big raw-memory effect.
2810 // Hook selected additional alias categories on the initialization.
2811 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
2812                                 MergeMemNode* init_in_merge,
2813                                 Node* init_out_raw) {
2814   DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
2815   assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
2816 
2817   Node* prevmem = kit.memory(alias_idx);
2818   init_in_merge->set_memory_at(alias_idx, prevmem);
2819   kit.set_memory(init_out_raw, alias_idx);
2820 }
2821 
2822 //---------------------------set_output_for_allocation-------------------------
2823 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
2824                                           const TypeOopPtr* oop_type,
2825                                           bool raw_mem_only) {
2826   int rawidx = Compile::AliasIdxRaw;
2827   alloc->set_req( TypeFunc::FramePtr, frameptr() );
2828   add_safepoint_edges(alloc);
2829   Node* allocx = _gvn.transform(alloc);
2830   set_control( _gvn.transform(new (C, 1) ProjNode(allocx, TypeFunc::Control) ) );
2831   // create memory projection for i_o
2832   set_memory ( _gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
2833   make_slow_call_ex(allocx, env()->OutOfMemoryError_klass(), true);
2834 
2835   // create a memory projection as for the normal control path
2836   Node* malloc = _gvn.transform(new (C, 1) ProjNode(allocx, TypeFunc::Memory));
2837   set_memory(malloc, rawidx);
2838 
2839   // a normal slow-call doesn't change i_o, but an allocation does
2840   // we create a separate i_o projection for the normal control path
2841   set_i_o(_gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::I_O, false) ) );
2842   Node* rawoop = _gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::Parms) );
2843 
2844   // put in an initialization barrier
2845   InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
2846                                                  rawoop)->as_Initialize();
2847   assert(alloc->initialization() == init,  "2-way macro link must work");
2848   assert(init ->allocation()     == alloc, "2-way macro link must work");
2849   if (ReduceFieldZeroing && !raw_mem_only) {
2850     // Extract memory strands which may participate in the new object's
2851     // initialization, and source them from the new InitializeNode.
2852     // This will allow us to observe initializations when they occur,
2853     // and link them properly (as a group) to the InitializeNode.
2854     assert(init->in(InitializeNode::Memory) == malloc, "");
2855     MergeMemNode* minit_in = MergeMemNode::make(C, malloc);
2856     init->set_req(InitializeNode::Memory, minit_in);
2857     record_for_igvn(minit_in); // fold it up later, if possible
2858     Node* minit_out = memory(rawidx);
2859     assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
2860     if (oop_type->isa_aryptr()) {
2861       const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
2862       int            elemidx  = C->get_alias_index(telemref);
2863       hook_memory_on_init(*this, elemidx, minit_in, minit_out);
2864     } else if (oop_type->isa_instptr()) {
2865       ciInstanceKlass* ik = oop_type->klass()->as_instance_klass();
2866       for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
2867         ciField* field = ik->nonstatic_field_at(i);
2868         if (field->offset() >= TrackedInitializationLimit * HeapWordSize)
2869           continue;  // do not bother to track really large numbers of fields
2870         // Find (or create) the alias category for this field:
2871         int fieldidx = C->alias_type(field)->index();
2872         hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
2873       }
2874     }
2875   }
2876 
2877   // Cast raw oop to the real thing...
2878   Node* javaoop = new (C, 2) CheckCastPPNode(control(), rawoop, oop_type);
2879   javaoop = _gvn.transform(javaoop);
2880   C->set_recent_alloc(control(), javaoop);
2881   assert(just_allocated_object(control()) == javaoop, "just allocated");
2882 
2883 #ifdef ASSERT
2884   { // Verify that the AllocateNode::Ideal_allocation recognizers work:
2885     assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc,
2886            "Ideal_allocation works");
2887     assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc,
2888            "Ideal_allocation works");
2889     if (alloc->is_AllocateArray()) {
2890       assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(),
2891              "Ideal_allocation works");
2892       assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(),
2893              "Ideal_allocation works");
2894     } else {
2895       assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
2896     }
2897   }
2898 #endif //ASSERT
2899 
2900   return javaoop;
2901 }
2902 
2903 //---------------------------new_instance--------------------------------------
2904 // This routine takes a klass_node which may be constant (for a static type)
2905 // or may be non-constant (for reflective code).  It will work equally well
2906 // for either, and the graph will fold nicely if the optimizer later reduces
2907 // the type to a constant.
2908 // The optional arguments are for specialized use by intrinsics:
2909 //  - If 'extra_slow_test' if not null is an extra condition for the slow-path.
2910 //  - If 'raw_mem_only', do not cast the result to an oop.
2911 //  - If 'return_size_val', report the the total object size to the caller.
2912 Node* GraphKit::new_instance(Node* klass_node,
2913                              Node* extra_slow_test,
2914                              bool raw_mem_only, // affect only raw memory
2915                              Node* *return_size_val) {
2916   // Compute size in doublewords
2917   // The size is always an integral number of doublewords, represented
2918   // as a positive bytewise size stored in the klass's layout_helper.
2919   // The layout_helper also encodes (in a low bit) the need for a slow path.
2920   jint  layout_con = Klass::_lh_neutral_value;
2921   Node* layout_val = get_layout_helper(klass_node, layout_con);
2922   int   layout_is_con = (layout_val == NULL);
2923 
2924   if (extra_slow_test == NULL)  extra_slow_test = intcon(0);
2925   // Generate the initial go-slow test.  It's either ALWAYS (return a
2926   // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective
2927   // case) a computed value derived from the layout_helper.
2928   Node* initial_slow_test = NULL;
2929   if (layout_is_con) {
2930     assert(!StressReflectiveCode, "stress mode does not use these paths");
2931     bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
2932     initial_slow_test = must_go_slow? intcon(1): extra_slow_test;
2933 
2934   } else {   // reflective case
2935     // This reflective path is used by Unsafe.allocateInstance.
2936     // (It may be stress-tested by specifying StressReflectiveCode.)
2937     // Basically, we want to get into the VM is there's an illegal argument.
2938     Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
2939     initial_slow_test = _gvn.transform( new (C, 3) AndINode(layout_val, bit) );
2940     if (extra_slow_test != intcon(0)) {
2941       initial_slow_test = _gvn.transform( new (C, 3) OrINode(initial_slow_test, extra_slow_test) );
2942     }
2943     // (Macro-expander will further convert this to a Bool, if necessary.)
2944   }
2945 
2946   // Find the size in bytes.  This is easy; it's the layout_helper.
2947   // The size value must be valid even if the slow path is taken.
2948   Node* size = NULL;
2949   if (layout_is_con) {
2950     size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
2951   } else {   // reflective case
2952     // This reflective path is used by clone and Unsafe.allocateInstance.
2953     size = ConvI2X(layout_val);
2954 
2955     // Clear the low bits to extract layout_helper_size_in_bytes:
2956     assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
2957     Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
2958     size = _gvn.transform( new (C, 3) AndXNode(size, mask) );
2959   }
2960   if (return_size_val != NULL) {
2961     (*return_size_val) = size;
2962   }
2963 
2964   // This is a precise notnull oop of the klass.
2965   // (Actually, it need not be precise if this is a reflective allocation.)
2966   // It's what we cast the result to.
2967   const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
2968   if (!tklass)  tklass = TypeKlassPtr::OBJECT;
2969   const TypeOopPtr* oop_type = tklass->as_instance_type();
2970 
2971   // Now generate allocation code
2972 
2973   // The entire memory state is needed for slow path of the allocation
2974   // since GC and deoptimization can happened.
2975   Node *mem = reset_memory();
2976   set_all_memory(mem); // Create new memory state
2977 
2978   AllocateNode* alloc
2979     = new (C, AllocateNode::ParmLimit)
2980         AllocateNode(C, AllocateNode::alloc_type(),
2981                      control(), mem, i_o(),
2982                      size, klass_node,
2983                      initial_slow_test);
2984 
2985   return set_output_for_allocation(alloc, oop_type, raw_mem_only);
2986 }
2987 
2988 //-------------------------------new_array-------------------------------------
2989 // helper for both newarray and anewarray
2990 // The 'length' parameter is (obviously) the length of the array.
2991 // See comments on new_instance for the meaning of the other arguments.
2992 Node* GraphKit::new_array(Node* klass_node,     // array klass (maybe variable)
2993                           Node* length,         // number of array elements
2994                           int   nargs,          // number of arguments to push back for uncommon trap
2995                           bool raw_mem_only,    // affect only raw memory
2996                           Node* *return_size_val) {
2997   jint  layout_con = Klass::_lh_neutral_value;
2998   Node* layout_val = get_layout_helper(klass_node, layout_con);
2999   int   layout_is_con = (layout_val == NULL);
3000 
3001   if (!layout_is_con && !StressReflectiveCode &&
3002       !too_many_traps(Deoptimization::Reason_class_check)) {
3003     // This is a reflective array creation site.
3004     // Optimistically assume that it is a subtype of Object[],
3005     // so that we can fold up all the address arithmetic.
3006     layout_con = Klass::array_layout_helper(T_OBJECT);
3007     Node* cmp_lh = _gvn.transform( new(C, 3) CmpINode(layout_val, intcon(layout_con)) );
3008     Node* bol_lh = _gvn.transform( new(C, 2) BoolNode(cmp_lh, BoolTest::eq) );
3009     { BuildCutout unless(this, bol_lh, PROB_MAX);
3010       _sp += nargs;
3011       uncommon_trap(Deoptimization::Reason_class_check,
3012                     Deoptimization::Action_maybe_recompile);
3013     }
3014     layout_val = NULL;
3015     layout_is_con = true;
3016   }
3017 
3018   // Generate the initial go-slow test.  Make sure we do not overflow
3019   // if length is huge (near 2Gig) or negative!  We do not need
3020   // exact double-words here, just a close approximation of needed
3021   // double-words.  We can't add any offset or rounding bits, lest we
3022   // take a size -1 of bytes and make it positive.  Use an unsigned
3023   // compare, so negative sizes look hugely positive.
3024   int fast_size_limit = FastAllocateSizeLimit;
3025   if (layout_is_con) {
3026     assert(!StressReflectiveCode, "stress mode does not use these paths");
3027     // Increase the size limit if we have exact knowledge of array type.
3028     int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3029     fast_size_limit <<= (LogBytesPerLong - log2_esize);
3030   }
3031 
3032   Node* initial_slow_cmp  = _gvn.transform( new (C, 3) CmpUNode( length, intcon( fast_size_limit ) ) );
3033   Node* initial_slow_test = _gvn.transform( new (C, 2) BoolNode( initial_slow_cmp, BoolTest::gt ) );
3034   if (initial_slow_test->is_Bool()) {
3035     // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3036     initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3037   }
3038 
3039   // --- Size Computation ---
3040   // array_size = round_to_heap(array_header + (length << elem_shift));
3041   // where round_to_heap(x) == round_to(x, MinObjAlignmentInBytes)
3042   // and round_to(x, y) == ((x + y-1) & ~(y-1))
3043   // The rounding mask is strength-reduced, if possible.
3044   int round_mask = MinObjAlignmentInBytes - 1;
3045   Node* header_size = NULL;
3046   int   header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3047   // (T_BYTE has the weakest alignment and size restrictions...)
3048   if (layout_is_con) {
3049     int       hsize  = Klass::layout_helper_header_size(layout_con);
3050     int       eshift = Klass::layout_helper_log2_element_size(layout_con);
3051     BasicType etype  = Klass::layout_helper_element_type(layout_con);
3052     if ((round_mask & ~right_n_bits(eshift)) == 0)
3053       round_mask = 0;  // strength-reduce it if it goes away completely
3054     assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3055     assert(header_size_min <= hsize, "generic minimum is smallest");
3056     header_size_min = hsize;
3057     header_size = intcon(hsize + round_mask);
3058   } else {
3059     Node* hss   = intcon(Klass::_lh_header_size_shift);
3060     Node* hsm   = intcon(Klass::_lh_header_size_mask);
3061     Node* hsize = _gvn.transform( new(C, 3) URShiftINode(layout_val, hss) );
3062     hsize       = _gvn.transform( new(C, 3) AndINode(hsize, hsm) );
3063     Node* mask  = intcon(round_mask);
3064     header_size = _gvn.transform( new(C, 3) AddINode(hsize, mask) );
3065   }
3066 
3067   Node* elem_shift = NULL;
3068   if (layout_is_con) {
3069     int eshift = Klass::layout_helper_log2_element_size(layout_con);
3070     if (eshift != 0)
3071       elem_shift = intcon(eshift);
3072   } else {
3073     // There is no need to mask or shift this value.
3074     // The semantics of LShiftINode include an implicit mask to 0x1F.
3075     assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3076     elem_shift = layout_val;
3077   }
3078 
3079   // Transition to native address size for all offset calculations:
3080   Node* lengthx = ConvI2X(length);
3081   Node* headerx = ConvI2X(header_size);
3082 #ifdef _LP64
3083   { const TypeLong* tllen = _gvn.find_long_type(lengthx);
3084     if (tllen != NULL && tllen->_lo < 0) {
3085       // Add a manual constraint to a positive range.  Cf. array_element_address.
3086       jlong size_max = arrayOopDesc::max_array_length(T_BYTE);
3087       if (size_max > tllen->_hi)  size_max = tllen->_hi;
3088       const TypeLong* tlcon = TypeLong::make(CONST64(0), size_max, Type::WidenMin);
3089       lengthx = _gvn.transform( new (C, 2) ConvI2LNode(length, tlcon));
3090     }
3091   }
3092 #endif
3093 
3094   // Combine header size (plus rounding) and body size.  Then round down.
3095   // This computation cannot overflow, because it is used only in two
3096   // places, one where the length is sharply limited, and the other
3097   // after a successful allocation.
3098   Node* abody = lengthx;
3099   if (elem_shift != NULL)
3100     abody     = _gvn.transform( new(C, 3) LShiftXNode(lengthx, elem_shift) );
3101   Node* size  = _gvn.transform( new(C, 3) AddXNode(headerx, abody) );
3102   if (round_mask != 0) {
3103     Node* mask = MakeConX(~round_mask);
3104     size       = _gvn.transform( new(C, 3) AndXNode(size, mask) );
3105   }
3106   // else if round_mask == 0, the size computation is self-rounding
3107 
3108   if (return_size_val != NULL) {
3109     // This is the size
3110     (*return_size_val) = size;
3111   }
3112 
3113   // Now generate allocation code
3114 
3115   // The entire memory state is needed for slow path of the allocation
3116   // since GC and deoptimization can happened.
3117   Node *mem = reset_memory();
3118   set_all_memory(mem); // Create new memory state
3119 
3120   // Create the AllocateArrayNode and its result projections
3121   AllocateArrayNode* alloc
3122     = new (C, AllocateArrayNode::ParmLimit)
3123         AllocateArrayNode(C, AllocateArrayNode::alloc_type(),
3124                           control(), mem, i_o(),
3125                           size, klass_node,
3126                           initial_slow_test,
3127                           length);
3128 
3129   // Cast to correct type.  Note that the klass_node may be constant or not,
3130   // and in the latter case the actual array type will be inexact also.
3131   // (This happens via a non-constant argument to inline_native_newArray.)
3132   // In any case, the value of klass_node provides the desired array type.
3133   const TypeInt* length_type = _gvn.find_int_type(length);
3134   const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3135   if (ary_type->isa_aryptr() && length_type != NULL) {
3136     // Try to get a better type than POS for the size
3137     ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3138   }
3139 
3140   Node* javaoop = set_output_for_allocation(alloc, ary_type, raw_mem_only);
3141 
3142   // Cast length on remaining path to be as narrow as possible
3143   if (map()->find_edge(length) >= 0) {
3144     Node* ccast = alloc->make_ideal_length(ary_type, &_gvn);
3145     if (ccast != length) {
3146       _gvn.set_type_bottom(ccast);
3147       record_for_igvn(ccast);
3148       replace_in_map(length, ccast);
3149     }
3150   }
3151 
3152   return javaoop;
3153 }
3154 
3155 // The following "Ideal_foo" functions are placed here because they recognize
3156 // the graph shapes created by the functions immediately above.
3157 
3158 //---------------------------Ideal_allocation----------------------------------
3159 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3160 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) {
3161   if (ptr == NULL) {     // reduce dumb test in callers
3162     return NULL;
3163   }
3164   if (ptr->is_CheckCastPP()) {  // strip a raw-to-oop cast
3165     ptr = ptr->in(1);
3166     if (ptr == NULL)  return NULL;
3167   }
3168   if (ptr->is_Proj()) {
3169     Node* allo = ptr->in(0);
3170     if (allo != NULL && allo->is_Allocate()) {
3171       return allo->as_Allocate();
3172     }
3173   }
3174   // Report failure to match.
3175   return NULL;
3176 }
3177 
3178 // Fancy version which also strips off an offset (and reports it to caller).
3179 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase,
3180                                              intptr_t& offset) {
3181   Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
3182   if (base == NULL)  return NULL;
3183   return Ideal_allocation(base, phase);
3184 }
3185 
3186 // Trace Initialize <- Proj[Parm] <- Allocate
3187 AllocateNode* InitializeNode::allocation() {
3188   Node* rawoop = in(InitializeNode::RawAddress);
3189   if (rawoop->is_Proj()) {
3190     Node* alloc = rawoop->in(0);
3191     if (alloc->is_Allocate()) {
3192       return alloc->as_Allocate();
3193     }
3194   }
3195   return NULL;
3196 }
3197 
3198 // Trace Allocate -> Proj[Parm] -> Initialize
3199 InitializeNode* AllocateNode::initialization() {
3200   ProjNode* rawoop = proj_out(AllocateNode::RawAddress);
3201   if (rawoop == NULL)  return NULL;
3202   for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3203     Node* init = rawoop->fast_out(i);
3204     if (init->is_Initialize()) {
3205       assert(init->as_Initialize()->allocation() == this, "2-way link");
3206       return init->as_Initialize();
3207     }
3208   }
3209   return NULL;
3210 }
3211 
3212 //----------------------------- store barriers ----------------------------
3213 #define __ ideal.
3214 
3215 void GraphKit::sync_kit(IdealKit& ideal) {
3216   // Final sync IdealKit and graphKit.
3217   __ drain_delay_transform();
3218   set_all_memory(__ merged_memory());
3219   set_control(__ ctrl());
3220 }
3221 
3222 // vanilla/CMS post barrier
3223 // Insert a write-barrier store.  This is to let generational GC work; we have
3224 // to flag all oop-stores before the next GC point.
3225 void GraphKit::write_barrier_post(Node* oop_store,
3226                                   Node* obj,
3227                                   Node* adr,
3228                                   uint  adr_idx,
3229                                   Node* val,
3230                                   bool use_precise) {
3231   // No store check needed if we're storing a NULL or an old object
3232   // (latter case is probably a string constant). The concurrent
3233   // mark sweep garbage collector, however, needs to have all nonNull
3234   // oop updates flagged via card-marks.
3235   if (val != NULL && val->is_Con()) {
3236     // must be either an oop or NULL
3237     const Type* t = val->bottom_type();
3238     if (t == TypePtr::NULL_PTR || t == Type::TOP)
3239       // stores of null never (?) need barriers
3240       return;
3241     ciObject* con = t->is_oopptr()->const_oop();
3242     if (con != NULL
3243         && con->is_perm()
3244         && Universe::heap()->can_elide_permanent_oop_store_barriers())
3245       // no store barrier needed, because no old-to-new ref created
3246       return;
3247   }
3248 
3249   if (use_ReduceInitialCardMarks()
3250       && obj == just_allocated_object(control())) {
3251     // We can skip marks on a freshly-allocated object in Eden.
3252     // Keep this code in sync with maybe_defer_card_mark() in runtime.cpp.
3253     // That routine informs GC to take appropriate compensating steps
3254     // so as to make this card-mark elision safe.
3255     return;
3256   }
3257 
3258   if (!use_precise) {
3259     // All card marks for a (non-array) instance are in one place:
3260     adr = obj;
3261   }
3262   // (Else it's an array (or unknown), and we want more precise card marks.)
3263   assert(adr != NULL, "");
3264 
3265   IdealKit ideal(gvn(), control(), merged_memory(), true);
3266 
3267   // Convert the pointer to an int prior to doing math on it
3268   Node* cast = __ CastPX(__ ctrl(), adr);
3269 
3270   // Divide by card size
3271   assert(Universe::heap()->barrier_set()->kind() == BarrierSet::CardTableModRef,
3272          "Only one we handle so far.");
3273   Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3274 
3275   // Combine card table base and card offset
3276   Node* card_adr = __ AddP(__ top(), byte_map_base_node(), card_offset );
3277 
3278   // Get the alias_index for raw card-mark memory
3279   int adr_type = Compile::AliasIdxRaw;
3280   // Smash zero into card
3281   Node*   zero = __ ConI(0);
3282   BasicType bt = T_BYTE;
3283   if( !UseConcMarkSweepGC ) {
3284     __ store(__ ctrl(), card_adr, zero, bt, adr_type);
3285   } else {
3286     // Specialized path for CM store barrier
3287     __ storeCM(__ ctrl(), card_adr, zero, oop_store, adr_idx, bt, adr_type);
3288   }
3289 
3290   // Final sync IdealKit and GraphKit.
3291   sync_kit(ideal);
3292 }
3293 
3294 // G1 pre/post barriers
3295 void GraphKit::g1_write_barrier_pre(Node* obj,
3296                                     Node* adr,
3297                                     uint alias_idx,
3298                                     Node* val,
3299                                     const TypeOopPtr* val_type,
3300                                     BasicType bt) {
3301   IdealKit ideal(gvn(), control(), merged_memory(), true);
3302 
3303   Node* tls = __ thread(); // ThreadLocalStorage
3304 
3305   Node* no_ctrl = NULL;
3306   Node* no_base = __ top();
3307   Node* zero = __ ConI(0);
3308 
3309   float likely  = PROB_LIKELY(0.999);
3310   float unlikely  = PROB_UNLIKELY(0.999);
3311 
3312   BasicType active_type = in_bytes(PtrQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE;
3313   assert(in_bytes(PtrQueue::byte_width_of_active()) == 4 || in_bytes(PtrQueue::byte_width_of_active()) == 1, "flag width");
3314 
3315   // Offsets into the thread
3316   const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() +  // 648
3317                                           PtrQueue::byte_offset_of_active());
3318   const int index_offset   = in_bytes(JavaThread::satb_mark_queue_offset() +  // 656
3319                                           PtrQueue::byte_offset_of_index());
3320   const int buffer_offset  = in_bytes(JavaThread::satb_mark_queue_offset() +  // 652
3321                                           PtrQueue::byte_offset_of_buf());
3322   // Now the actual pointers into the thread
3323 
3324   // set_control( ctl);
3325 
3326   Node* marking_adr = __ AddP(no_base, tls, __ ConX(marking_offset));
3327   Node* buffer_adr  = __ AddP(no_base, tls, __ ConX(buffer_offset));
3328   Node* index_adr   = __ AddP(no_base, tls, __ ConX(index_offset));
3329 
3330   // Now some of the values
3331 
3332   Node* marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw);
3333 
3334   // if (!marking)
3335   __ if_then(marking, BoolTest::ne, zero); {
3336     Node* index   = __ load(__ ctrl(), index_adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw);
3337 
3338     const Type* t1 = adr->bottom_type();
3339     const Type* t2 = val->bottom_type();
3340 
3341     Node* orig = __ load(no_ctrl, adr, val_type, bt, alias_idx);
3342     // if (orig != NULL)
3343     __ if_then(orig, BoolTest::ne, null()); {
3344       Node* buffer  = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
3345 
3346       // load original value
3347       // alias_idx correct??
3348 
3349       // is the queue for this thread full?
3350       __ if_then(index, BoolTest::ne, zero, likely); {
3351 
3352         // decrement the index
3353         Node* next_index = __ SubI(index,  __ ConI(sizeof(intptr_t)));
3354         Node* next_indexX = next_index;
3355 #ifdef _LP64
3356         // We could refine the type for what it's worth
3357         // const TypeLong* lidxtype = TypeLong::make(CONST64(0), get_size_from_queue);
3358         next_indexX = _gvn.transform( new (C, 2) ConvI2LNode(next_index, TypeLong::make(0, max_jlong, Type::WidenMax)) );
3359 #endif
3360 
3361         // Now get the buffer location we will log the original value into and store it
3362         Node *log_addr = __ AddP(no_base, buffer, next_indexX);
3363         __ store(__ ctrl(), log_addr, orig, T_OBJECT, Compile::AliasIdxRaw);
3364 
3365         // update the index
3366         __ store(__ ctrl(), index_adr, next_index, T_INT, Compile::AliasIdxRaw);
3367 
3368       } __ else_(); {
3369 
3370         // logging buffer is full, call the runtime
3371         const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type();
3372         __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", orig, tls);
3373       } __ end_if();  // (!index)
3374     } __ end_if();  // (orig != NULL)
3375   } __ end_if();  // (!marking)
3376 
3377   // Final sync IdealKit and GraphKit.
3378   sync_kit(ideal);
3379 }
3380 
3381 //
3382 // Update the card table and add card address to the queue
3383 //
3384 void GraphKit::g1_mark_card(IdealKit& ideal,
3385                             Node* card_adr,
3386                             Node* oop_store,
3387                             uint oop_alias_idx,
3388                             Node* index,
3389                             Node* index_adr,
3390                             Node* buffer,
3391                             const TypeFunc* tf) {
3392 
3393   Node* zero = __ ConI(0);
3394   Node* no_base = __ top();
3395   BasicType card_bt = T_BYTE;
3396   // Smash zero into card. MUST BE ORDERED WRT TO STORE
3397   __ storeCM(__ ctrl(), card_adr, zero, oop_store, oop_alias_idx, card_bt, Compile::AliasIdxRaw);
3398 
3399   //  Now do the queue work
3400   __ if_then(index, BoolTest::ne, zero); {
3401 
3402     Node* next_index = __ SubI(index, __ ConI(sizeof(intptr_t)));
3403     Node* next_indexX = next_index;
3404 #ifdef _LP64
3405     // We could refine the type for what it's worth
3406     // const TypeLong* lidxtype = TypeLong::make(CONST64(0), get_size_from_queue);
3407     next_indexX = _gvn.transform( new (C, 2) ConvI2LNode(next_index, TypeLong::make(0, max_jlong, Type::WidenMax)) );
3408 #endif // _LP64
3409     Node* log_addr = __ AddP(no_base, buffer, next_indexX);
3410 
3411     __ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw);
3412     __ store(__ ctrl(), index_adr, next_index, T_INT, Compile::AliasIdxRaw);
3413 
3414   } __ else_(); {
3415     __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread());
3416   } __ end_if();
3417 
3418 }
3419 
3420 void GraphKit::g1_write_barrier_post(Node* oop_store,
3421                                      Node* obj,
3422                                      Node* adr,
3423                                      uint alias_idx,
3424                                      Node* val,
3425                                      BasicType bt,
3426                                      bool use_precise) {
3427   // If we are writing a NULL then we need no post barrier
3428 
3429   if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) {
3430     // Must be NULL
3431     const Type* t = val->bottom_type();
3432     assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL");
3433     // No post barrier if writing NULLx
3434     return;
3435   }
3436 
3437   if (!use_precise) {
3438     // All card marks for a (non-array) instance are in one place:
3439     adr = obj;
3440   }
3441   // (Else it's an array (or unknown), and we want more precise card marks.)
3442   assert(adr != NULL, "");
3443 
3444   IdealKit ideal(gvn(), control(), merged_memory(), true);
3445 
3446   Node* tls = __ thread(); // ThreadLocalStorage
3447 
3448   Node* no_ctrl = NULL;
3449   Node* no_base = __ top();
3450   float likely  = PROB_LIKELY(0.999);
3451   float unlikely  = PROB_UNLIKELY(0.999);
3452   Node* zero = __ ConI(0);
3453   Node* zeroX = __ ConX(0);
3454 
3455   // Get the alias_index for raw card-mark memory
3456   const TypePtr* card_type = TypeRawPtr::BOTTOM;
3457 
3458   const TypeFunc *tf = OptoRuntime::g1_wb_post_Type();
3459 
3460   // Offsets into the thread
3461   const int index_offset  = in_bytes(JavaThread::dirty_card_queue_offset() +
3462                                      PtrQueue::byte_offset_of_index());
3463   const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
3464                                      PtrQueue::byte_offset_of_buf());
3465 
3466   // Pointers into the thread
3467 
3468   Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
3469   Node* index_adr =  __ AddP(no_base, tls, __ ConX(index_offset));
3470 
3471   // Now some values
3472 
3473   Node* index  = __ load(no_ctrl, index_adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw);
3474   Node* buffer = __ load(no_ctrl, buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
3475 
3476 
3477   // Convert the store obj pointer to an int prior to doing math on it
3478   // Must use ctrl to prevent "integerized oop" existing across safepoint
3479   Node* cast =  __ CastPX(__ ctrl(), adr);
3480 
3481   // Divide pointer by card size
3482   Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3483 
3484   // Combine card table base and card offset
3485   Node* card_adr = __ AddP(no_base, byte_map_base_node(), card_offset );
3486 
3487   // If we know the value being stored does it cross regions?
3488 
3489   if (val != NULL) {
3490     // Does the store cause us to cross regions?
3491 
3492     // Should be able to do an unsigned compare of region_size instead of
3493     // and extra shift. Do we have an unsigned compare??
3494     // Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes);
3495     Node* xor_res =  __ URShiftX ( __ XorX( cast,  __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes));
3496 
3497     // if (xor_res == 0) same region so skip
3498     __ if_then(xor_res, BoolTest::ne, zeroX); {
3499 
3500       // No barrier if we are storing a NULL
3501       __ if_then(val, BoolTest::ne, null(), unlikely); {
3502 
3503         // Ok must mark the card if not already dirty
3504 
3505         // load the original value of the card
3506         Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
3507 
3508         __ if_then(card_val, BoolTest::ne, zero); {
3509           g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
3510         } __ end_if();
3511       } __ end_if();
3512     } __ end_if();
3513   } else {
3514     // Object.clone() instrinsic uses this path.
3515     g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
3516   }
3517 
3518   // Final sync IdealKit and GraphKit.
3519   sync_kit(ideal);
3520 }
3521 #undef __