1 /*
   2  * Copyright (c) 2001, 2011, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "compiler/compileLog.hpp"
  27 #include "gc_implementation/g1/g1SATBCardTableModRefBS.hpp"
  28 #include "gc_implementation/g1/heapRegion.hpp"
  29 #include "gc_interface/collectedHeap.hpp"
  30 #include "memory/barrierSet.hpp"
  31 #include "memory/cardTableModRefBS.hpp"
  32 #include "opto/addnode.hpp"
  33 #include "opto/graphKit.hpp"
  34 #include "opto/idealKit.hpp"
  35 #include "opto/locknode.hpp"
  36 #include "opto/machnode.hpp"
  37 #include "opto/parse.hpp"
  38 #include "opto/rootnode.hpp"
  39 #include "opto/runtime.hpp"
  40 #include "runtime/deoptimization.hpp"
  41 #include "runtime/sharedRuntime.hpp"
  42 
  43 //----------------------------GraphKit-----------------------------------------
  44 // Main utility constructor.
  45 GraphKit::GraphKit(JVMState* jvms)
  46   : Phase(Phase::Parser),
  47     _env(C->env()),
  48     _gvn(*C->initial_gvn())
  49 {
  50   _exceptions = jvms->map()->next_exception();
  51   if (_exceptions != NULL)  jvms->map()->set_next_exception(NULL);
  52   set_jvms(jvms);
  53 }
  54 
  55 // Private constructor for parser.
  56 GraphKit::GraphKit()
  57   : Phase(Phase::Parser),
  58     _env(C->env()),
  59     _gvn(*C->initial_gvn())
  60 {
  61   _exceptions = NULL;
  62   set_map(NULL);
  63   debug_only(_sp = -99);
  64   debug_only(set_bci(-99));
  65 }
  66 
  67 
  68 
  69 //---------------------------clean_stack---------------------------------------
  70 // Clear away rubbish from the stack area of the JVM state.
  71 // This destroys any arguments that may be waiting on the stack.
  72 void GraphKit::clean_stack(int from_sp) {
  73   SafePointNode* map      = this->map();
  74   JVMState*      jvms     = this->jvms();
  75   int            stk_size = jvms->stk_size();
  76   int            stkoff   = jvms->stkoff();
  77   Node*          top      = this->top();
  78   for (int i = from_sp; i < stk_size; i++) {
  79     if (map->in(stkoff + i) != top) {
  80       map->set_req(stkoff + i, top);
  81     }
  82   }
  83 }
  84 
  85 
  86 //--------------------------------sync_jvms-----------------------------------
  87 // Make sure our current jvms agrees with our parse state.
  88 JVMState* GraphKit::sync_jvms() const {
  89   JVMState* jvms = this->jvms();
  90   jvms->set_bci(bci());       // Record the new bci in the JVMState
  91   jvms->set_sp(sp());         // Record the new sp in the JVMState
  92   assert(jvms_in_sync(), "jvms is now in sync");
  93   return jvms;
  94 }
  95 
  96 #ifdef ASSERT
  97 bool GraphKit::jvms_in_sync() const {
  98   Parse* parse = is_Parse();
  99   if (parse == NULL) {
 100     if (bci() !=      jvms()->bci())          return false;
 101     if (sp()  != (int)jvms()->sp())           return false;
 102     return true;
 103   }
 104   if (jvms()->method() != parse->method())    return false;
 105   if (jvms()->bci()    != parse->bci())       return false;
 106   int jvms_sp = jvms()->sp();
 107   if (jvms_sp          != parse->sp())        return false;
 108   int jvms_depth = jvms()->depth();
 109   if (jvms_depth       != parse->depth())     return false;
 110   return true;
 111 }
 112 
 113 // Local helper checks for special internal merge points
 114 // used to accumulate and merge exception states.
 115 // They are marked by the region's in(0) edge being the map itself.
 116 // Such merge points must never "escape" into the parser at large,
 117 // until they have been handed to gvn.transform.
 118 static bool is_hidden_merge(Node* reg) {
 119   if (reg == NULL)  return false;
 120   if (reg->is_Phi()) {
 121     reg = reg->in(0);
 122     if (reg == NULL)  return false;
 123   }
 124   return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root();
 125 }
 126 
 127 void GraphKit::verify_map() const {
 128   if (map() == NULL)  return;  // null map is OK
 129   assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
 130   assert(!map()->has_exceptions(),    "call add_exception_states_from 1st");
 131   assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
 132 }
 133 
 134 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
 135   assert(ex_map->next_exception() == NULL, "not already part of a chain");
 136   assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
 137 }
 138 #endif
 139 
 140 //---------------------------stop_and_kill_map---------------------------------
 141 // Set _map to NULL, signalling a stop to further bytecode execution.
 142 // First smash the current map's control to a constant, to mark it dead.
 143 void GraphKit::stop_and_kill_map() {
 144   SafePointNode* dead_map = stop();
 145   if (dead_map != NULL) {
 146     dead_map->disconnect_inputs(NULL); // Mark the map as killed.
 147     assert(dead_map->is_killed(), "must be so marked");
 148   }
 149 }
 150 
 151 
 152 //--------------------------------stopped--------------------------------------
 153 // Tell if _map is NULL, or control is top.
 154 bool GraphKit::stopped() {
 155   if (map() == NULL)           return true;
 156   else if (control() == top()) return true;
 157   else                         return false;
 158 }
 159 
 160 
 161 //-----------------------------has_ex_handler----------------------------------
 162 // Tell if this method or any caller method has exception handlers.
 163 bool GraphKit::has_ex_handler() {
 164   for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) {
 165     if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
 166       return true;
 167     }
 168   }
 169   return false;
 170 }
 171 
 172 //------------------------------save_ex_oop------------------------------------
 173 // Save an exception without blowing stack contents or other JVM state.
 174 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
 175   assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
 176   ex_map->add_req(ex_oop);
 177   debug_only(verify_exception_state(ex_map));
 178 }
 179 
 180 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
 181   assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
 182   Node* ex_oop = ex_map->in(ex_map->req()-1);
 183   if (clear_it)  ex_map->del_req(ex_map->req()-1);
 184   return ex_oop;
 185 }
 186 
 187 //-----------------------------saved_ex_oop------------------------------------
 188 // Recover a saved exception from its map.
 189 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
 190   return common_saved_ex_oop(ex_map, false);
 191 }
 192 
 193 //--------------------------clear_saved_ex_oop---------------------------------
 194 // Erase a previously saved exception from its map.
 195 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
 196   return common_saved_ex_oop(ex_map, true);
 197 }
 198 
 199 #ifdef ASSERT
 200 //---------------------------has_saved_ex_oop----------------------------------
 201 // Erase a previously saved exception from its map.
 202 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
 203   return ex_map->req() == ex_map->jvms()->endoff()+1;
 204 }
 205 #endif
 206 
 207 //-------------------------make_exception_state--------------------------------
 208 // Turn the current JVM state into an exception state, appending the ex_oop.
 209 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
 210   sync_jvms();
 211   SafePointNode* ex_map = stop();  // do not manipulate this map any more
 212   set_saved_ex_oop(ex_map, ex_oop);
 213   return ex_map;
 214 }
 215 
 216 
 217 //--------------------------add_exception_state--------------------------------
 218 // Add an exception to my list of exceptions.
 219 void GraphKit::add_exception_state(SafePointNode* ex_map) {
 220   if (ex_map == NULL || ex_map->control() == top()) {
 221     return;
 222   }
 223 #ifdef ASSERT
 224   verify_exception_state(ex_map);
 225   if (has_exceptions()) {
 226     assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
 227   }
 228 #endif
 229 
 230   // If there is already an exception of exactly this type, merge with it.
 231   // In particular, null-checks and other low-level exceptions common up here.
 232   Node*       ex_oop  = saved_ex_oop(ex_map);
 233   const Type* ex_type = _gvn.type(ex_oop);
 234   if (ex_oop == top()) {
 235     // No action needed.
 236     return;
 237   }
 238   assert(ex_type->isa_instptr(), "exception must be an instance");
 239   for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) {
 240     const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
 241     // We check sp also because call bytecodes can generate exceptions
 242     // both before and after arguments are popped!
 243     if (ex_type2 == ex_type
 244         && e2->_jvms->sp() == ex_map->_jvms->sp()) {
 245       combine_exception_states(ex_map, e2);
 246       return;
 247     }
 248   }
 249 
 250   // No pre-existing exception of the same type.  Chain it on the list.
 251   push_exception_state(ex_map);
 252 }
 253 
 254 //-----------------------add_exception_states_from-----------------------------
 255 void GraphKit::add_exception_states_from(JVMState* jvms) {
 256   SafePointNode* ex_map = jvms->map()->next_exception();
 257   if (ex_map != NULL) {
 258     jvms->map()->set_next_exception(NULL);
 259     for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) {
 260       next_map = ex_map->next_exception();
 261       ex_map->set_next_exception(NULL);
 262       add_exception_state(ex_map);
 263     }
 264   }
 265 }
 266 
 267 //-----------------------transfer_exceptions_into_jvms-------------------------
 268 JVMState* GraphKit::transfer_exceptions_into_jvms() {
 269   if (map() == NULL) {
 270     // We need a JVMS to carry the exceptions, but the map has gone away.
 271     // Create a scratch JVMS, cloned from any of the exception states...
 272     if (has_exceptions()) {
 273       _map = _exceptions;
 274       _map = clone_map();
 275       _map->set_next_exception(NULL);
 276       clear_saved_ex_oop(_map);
 277       debug_only(verify_map());
 278     } else {
 279       // ...or created from scratch
 280       JVMState* jvms = new (C) JVMState(_method, NULL);
 281       jvms->set_bci(_bci);
 282       jvms->set_sp(_sp);
 283       jvms->set_map(new (C, TypeFunc::Parms) SafePointNode(TypeFunc::Parms, jvms));
 284       set_jvms(jvms);
 285       for (uint i = 0; i < map()->req(); i++)  map()->init_req(i, top());
 286       set_all_memory(top());
 287       while (map()->req() < jvms->endoff())  map()->add_req(top());
 288     }
 289     // (This is a kludge, in case you didn't notice.)
 290     set_control(top());
 291   }
 292   JVMState* jvms = sync_jvms();
 293   assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
 294   jvms->map()->set_next_exception(_exceptions);
 295   _exceptions = NULL;   // done with this set of exceptions
 296   return jvms;
 297 }
 298 
 299 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
 300   assert(is_hidden_merge(dstphi), "must be a special merge node");
 301   assert(is_hidden_merge(srcphi), "must be a special merge node");
 302   uint limit = srcphi->req();
 303   for (uint i = PhiNode::Input; i < limit; i++) {
 304     dstphi->add_req(srcphi->in(i));
 305   }
 306 }
 307 static inline void add_one_req(Node* dstphi, Node* src) {
 308   assert(is_hidden_merge(dstphi), "must be a special merge node");
 309   assert(!is_hidden_merge(src), "must not be a special merge node");
 310   dstphi->add_req(src);
 311 }
 312 
 313 //-----------------------combine_exception_states------------------------------
 314 // This helper function combines exception states by building phis on a
 315 // specially marked state-merging region.  These regions and phis are
 316 // untransformed, and can build up gradually.  The region is marked by
 317 // having a control input of its exception map, rather than NULL.  Such
 318 // regions do not appear except in this function, and in use_exception_state.
 319 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
 320   if (failing())  return;  // dying anyway...
 321   JVMState* ex_jvms = ex_map->_jvms;
 322   assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
 323   assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
 324   assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
 325   assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
 326   assert(ex_map->req() == phi_map->req(), "matching maps");
 327   uint tos = ex_jvms->stkoff() + ex_jvms->sp();
 328   Node*         hidden_merge_mark = root();
 329   Node*         region  = phi_map->control();
 330   MergeMemNode* phi_mem = phi_map->merged_memory();
 331   MergeMemNode* ex_mem  = ex_map->merged_memory();
 332   if (region->in(0) != hidden_merge_mark) {
 333     // The control input is not (yet) a specially-marked region in phi_map.
 334     // Make it so, and build some phis.
 335     region = new (C, 2) RegionNode(2);
 336     _gvn.set_type(region, Type::CONTROL);
 337     region->set_req(0, hidden_merge_mark);  // marks an internal ex-state
 338     region->init_req(1, phi_map->control());
 339     phi_map->set_control(region);
 340     Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
 341     record_for_igvn(io_phi);
 342     _gvn.set_type(io_phi, Type::ABIO);
 343     phi_map->set_i_o(io_phi);
 344     for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
 345       Node* m = mms.memory();
 346       Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
 347       record_for_igvn(m_phi);
 348       _gvn.set_type(m_phi, Type::MEMORY);
 349       mms.set_memory(m_phi);
 350     }
 351   }
 352 
 353   // Either or both of phi_map and ex_map might already be converted into phis.
 354   Node* ex_control = ex_map->control();
 355   // if there is special marking on ex_map also, we add multiple edges from src
 356   bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
 357   // how wide was the destination phi_map, originally?
 358   uint orig_width = region->req();
 359 
 360   if (add_multiple) {
 361     add_n_reqs(region, ex_control);
 362     add_n_reqs(phi_map->i_o(), ex_map->i_o());
 363   } else {
 364     // ex_map has no merges, so we just add single edges everywhere
 365     add_one_req(region, ex_control);
 366     add_one_req(phi_map->i_o(), ex_map->i_o());
 367   }
 368   for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
 369     if (mms.is_empty()) {
 370       // get a copy of the base memory, and patch some inputs into it
 371       const TypePtr* adr_type = mms.adr_type(C);
 372       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
 373       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
 374       mms.set_memory(phi);
 375       // Prepare to append interesting stuff onto the newly sliced phi:
 376       while (phi->req() > orig_width)  phi->del_req(phi->req()-1);
 377     }
 378     // Append stuff from ex_map:
 379     if (add_multiple) {
 380       add_n_reqs(mms.memory(), mms.memory2());
 381     } else {
 382       add_one_req(mms.memory(), mms.memory2());
 383     }
 384   }
 385   uint limit = ex_map->req();
 386   for (uint i = TypeFunc::Parms; i < limit; i++) {
 387     // Skip everything in the JVMS after tos.  (The ex_oop follows.)
 388     if (i == tos)  i = ex_jvms->monoff();
 389     Node* src = ex_map->in(i);
 390     Node* dst = phi_map->in(i);
 391     if (src != dst) {
 392       PhiNode* phi;
 393       if (dst->in(0) != region) {
 394         dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
 395         record_for_igvn(phi);
 396         _gvn.set_type(phi, phi->type());
 397         phi_map->set_req(i, dst);
 398         // Prepare to append interesting stuff onto the new phi:
 399         while (dst->req() > orig_width)  dst->del_req(dst->req()-1);
 400       } else {
 401         assert(dst->is_Phi(), "nobody else uses a hidden region");
 402         phi = (PhiNode*)dst;
 403       }
 404       if (add_multiple && src->in(0) == ex_control) {
 405         // Both are phis.
 406         add_n_reqs(dst, src);
 407       } else {
 408         while (dst->req() < region->req())  add_one_req(dst, src);
 409       }
 410       const Type* srctype = _gvn.type(src);
 411       if (phi->type() != srctype) {
 412         const Type* dsttype = phi->type()->meet(srctype);
 413         if (phi->type() != dsttype) {
 414           phi->set_type(dsttype);
 415           _gvn.set_type(phi, dsttype);
 416         }
 417       }
 418     }
 419   }
 420 }
 421 
 422 //--------------------------use_exception_state--------------------------------
 423 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
 424   if (failing()) { stop(); return top(); }
 425   Node* region = phi_map->control();
 426   Node* hidden_merge_mark = root();
 427   assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
 428   Node* ex_oop = clear_saved_ex_oop(phi_map);
 429   if (region->in(0) == hidden_merge_mark) {
 430     // Special marking for internal ex-states.  Process the phis now.
 431     region->set_req(0, region);  // now it's an ordinary region
 432     set_jvms(phi_map->jvms());   // ...so now we can use it as a map
 433     // Note: Setting the jvms also sets the bci and sp.
 434     set_control(_gvn.transform(region));
 435     uint tos = jvms()->stkoff() + sp();
 436     for (uint i = 1; i < tos; i++) {
 437       Node* x = phi_map->in(i);
 438       if (x->in(0) == region) {
 439         assert(x->is_Phi(), "expected a special phi");
 440         phi_map->set_req(i, _gvn.transform(x));
 441       }
 442     }
 443     for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
 444       Node* x = mms.memory();
 445       if (x->in(0) == region) {
 446         assert(x->is_Phi(), "nobody else uses a hidden region");
 447         mms.set_memory(_gvn.transform(x));
 448       }
 449     }
 450     if (ex_oop->in(0) == region) {
 451       assert(ex_oop->is_Phi(), "expected a special phi");
 452       ex_oop = _gvn.transform(ex_oop);
 453     }
 454   } else {
 455     set_jvms(phi_map->jvms());
 456   }
 457 
 458   assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
 459   assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
 460   return ex_oop;
 461 }
 462 
 463 //---------------------------------java_bc-------------------------------------
 464 Bytecodes::Code GraphKit::java_bc() const {
 465   ciMethod* method = this->method();
 466   int       bci    = this->bci();
 467   if (method != NULL && bci != InvocationEntryBci)
 468     return method->java_code_at_bci(bci);
 469   else
 470     return Bytecodes::_illegal;
 471 }
 472 
 473 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
 474                                                           bool must_throw) {
 475     // if the exception capability is set, then we will generate code
 476     // to check the JavaThread.should_post_on_exceptions flag to see
 477     // if we actually need to report exception events (for this
 478     // thread).  If we don't need to report exception events, we will
 479     // take the normal fast path provided by add_exception_events.  If
 480     // exception event reporting is enabled for this thread, we will
 481     // take the uncommon_trap in the BuildCutout below.
 482 
 483     // first must access the should_post_on_exceptions_flag in this thread's JavaThread
 484     Node* jthread = _gvn.transform(new (C, 1) ThreadLocalNode());
 485     Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
 486     Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw, false);
 487 
 488     // Test the should_post_on_exceptions_flag vs. 0
 489     Node* chk = _gvn.transform( new (C, 3) CmpINode(should_post_flag, intcon(0)) );
 490     Node* tst = _gvn.transform( new (C, 2) BoolNode(chk, BoolTest::eq) );
 491 
 492     // Branch to slow_path if should_post_on_exceptions_flag was true
 493     { BuildCutout unless(this, tst, PROB_MAX);
 494       // Do not try anything fancy if we're notifying the VM on every throw.
 495       // Cf. case Bytecodes::_athrow in parse2.cpp.
 496       uncommon_trap(reason, Deoptimization::Action_none,
 497                     (ciKlass*)NULL, (char*)NULL, must_throw);
 498     }
 499 
 500 }
 501 
 502 //------------------------------builtin_throw----------------------------------
 503 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) {
 504   bool must_throw = true;
 505 
 506   if (env()->jvmti_can_post_on_exceptions()) {
 507     // check if we must post exception events, take uncommon trap if so
 508     uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
 509     // here if should_post_on_exceptions is false
 510     // continue on with the normal codegen
 511   }
 512 
 513   // If this particular condition has not yet happened at this
 514   // bytecode, then use the uncommon trap mechanism, and allow for
 515   // a future recompilation if several traps occur here.
 516   // If the throw is hot, try to use a more complicated inline mechanism
 517   // which keeps execution inside the compiled code.
 518   bool treat_throw_as_hot = false;
 519   ciMethodData* md = method()->method_data();
 520 
 521   if (ProfileTraps) {
 522     if (too_many_traps(reason)) {
 523       treat_throw_as_hot = true;
 524     }
 525     // (If there is no MDO at all, assume it is early in
 526     // execution, and that any deopts are part of the
 527     // startup transient, and don't need to be remembered.)
 528 
 529     // Also, if there is a local exception handler, treat all throws
 530     // as hot if there has been at least one in this method.
 531     if (C->trap_count(reason) != 0
 532         && method()->method_data()->trap_count(reason) != 0
 533         && has_ex_handler()) {
 534         treat_throw_as_hot = true;
 535     }
 536   }
 537 
 538   // If this throw happens frequently, an uncommon trap might cause
 539   // a performance pothole.  If there is a local exception handler,
 540   // and if this particular bytecode appears to be deoptimizing often,
 541   // let us handle the throw inline, with a preconstructed instance.
 542   // Note:   If the deopt count has blown up, the uncommon trap
 543   // runtime is going to flush this nmethod, not matter what.
 544   if (treat_throw_as_hot
 545       && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) {
 546     // If the throw is local, we use a pre-existing instance and
 547     // punt on the backtrace.  This would lead to a missing backtrace
 548     // (a repeat of 4292742) if the backtrace object is ever asked
 549     // for its backtrace.
 550     // Fixing this remaining case of 4292742 requires some flavor of
 551     // escape analysis.  Leave that for the future.
 552     ciInstance* ex_obj = NULL;
 553     switch (reason) {
 554     case Deoptimization::Reason_null_check:
 555       ex_obj = env()->NullPointerException_instance();
 556       break;
 557     case Deoptimization::Reason_div0_check:
 558       ex_obj = env()->ArithmeticException_instance();
 559       break;
 560     case Deoptimization::Reason_range_check:
 561       ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
 562       break;
 563     case Deoptimization::Reason_class_check:
 564       if (java_bc() == Bytecodes::_aastore) {
 565         ex_obj = env()->ArrayStoreException_instance();
 566       } else {
 567         ex_obj = env()->ClassCastException_instance();
 568       }
 569       break;
 570     }
 571     if (failing()) { stop(); return; }  // exception allocation might fail
 572     if (ex_obj != NULL) {
 573       // Cheat with a preallocated exception object.
 574       if (C->log() != NULL)
 575         C->log()->elem("hot_throw preallocated='1' reason='%s'",
 576                        Deoptimization::trap_reason_name(reason));
 577       const TypeInstPtr* ex_con  = TypeInstPtr::make(ex_obj);
 578       Node*              ex_node = _gvn.transform( ConNode::make(C, ex_con) );
 579 
 580       // Clear the detail message of the preallocated exception object.
 581       // Weblogic sometimes mutates the detail message of exceptions
 582       // using reflection.
 583       int offset = java_lang_Throwable::get_detailMessage_offset();
 584       const TypePtr* adr_typ = ex_con->add_offset(offset);
 585 
 586       Node *adr = basic_plus_adr(ex_node, ex_node, offset);
 587       const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
 588       Node *store = store_oop_to_object(control(), ex_node, adr, adr_typ, null(), val_type, T_OBJECT);
 589 
 590       add_exception_state(make_exception_state(ex_node));
 591       return;
 592     }
 593   }
 594 
 595   // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
 596   // It won't be much cheaper than bailing to the interp., since we'll
 597   // have to pass up all the debug-info, and the runtime will have to
 598   // create the stack trace.
 599 
 600   // Usual case:  Bail to interpreter.
 601   // Reserve the right to recompile if we haven't seen anything yet.
 602 
 603   Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
 604   if (treat_throw_as_hot
 605       && (method()->method_data()->trap_recompiled_at(bci())
 606           || C->too_many_traps(reason))) {
 607     // We cannot afford to take more traps here.  Suffer in the interpreter.
 608     if (C->log() != NULL)
 609       C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
 610                      Deoptimization::trap_reason_name(reason),
 611                      C->trap_count(reason));
 612     action = Deoptimization::Action_none;
 613   }
 614 
 615   // "must_throw" prunes the JVM state to include only the stack, if there
 616   // are no local exception handlers.  This should cut down on register
 617   // allocation time and code size, by drastically reducing the number
 618   // of in-edges on the call to the uncommon trap.
 619 
 620   uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw);
 621 }
 622 
 623 
 624 //----------------------------PreserveJVMState---------------------------------
 625 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
 626   debug_only(kit->verify_map());
 627   _kit    = kit;
 628   _map    = kit->map();   // preserve the map
 629   _sp     = kit->sp();
 630   kit->set_map(clone_map ? kit->clone_map() : NULL);
 631 #ifdef ASSERT
 632   _bci    = kit->bci();
 633   Parse* parser = kit->is_Parse();
 634   int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
 635   _block  = block;
 636 #endif
 637 }
 638 PreserveJVMState::~PreserveJVMState() {
 639   GraphKit* kit = _kit;
 640 #ifdef ASSERT
 641   assert(kit->bci() == _bci, "bci must not shift");
 642   Parse* parser = kit->is_Parse();
 643   int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
 644   assert(block == _block,    "block must not shift");
 645 #endif
 646   kit->set_map(_map);
 647   kit->set_sp(_sp);
 648 }
 649 
 650 
 651 //-----------------------------BuildCutout-------------------------------------
 652 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
 653   : PreserveJVMState(kit)
 654 {
 655   assert(p->is_Con() || p->is_Bool(), "test must be a bool");
 656   SafePointNode* outer_map = _map;   // preserved map is caller's
 657   SafePointNode* inner_map = kit->map();
 658   IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
 659   outer_map->set_control(kit->gvn().transform( new (kit->C, 1) IfTrueNode(iff) ));
 660   inner_map->set_control(kit->gvn().transform( new (kit->C, 1) IfFalseNode(iff) ));
 661 }
 662 BuildCutout::~BuildCutout() {
 663   GraphKit* kit = _kit;
 664   assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
 665 }
 666 
 667 //---------------------------PreserveReexecuteState----------------------------
 668 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
 669   assert(!kit->stopped(), "must call stopped() before");
 670   _kit    =    kit;
 671   _sp     =    kit->sp();
 672   _reexecute = kit->jvms()->_reexecute;
 673 }
 674 PreserveReexecuteState::~PreserveReexecuteState() {
 675   if (_kit->stopped()) return;
 676   _kit->jvms()->_reexecute = _reexecute;
 677   _kit->set_sp(_sp);
 678 }
 679 
 680 //------------------------------clone_map--------------------------------------
 681 // Implementation of PreserveJVMState
 682 //
 683 // Only clone_map(...) here. If this function is only used in the
 684 // PreserveJVMState class we may want to get rid of this extra
 685 // function eventually and do it all there.
 686 
 687 SafePointNode* GraphKit::clone_map() {
 688   if (map() == NULL)  return NULL;
 689 
 690   // Clone the memory edge first
 691   Node* mem = MergeMemNode::make(C, map()->memory());
 692   gvn().set_type_bottom(mem);
 693 
 694   SafePointNode *clonemap = (SafePointNode*)map()->clone();
 695   JVMState* jvms = this->jvms();
 696   JVMState* clonejvms = jvms->clone_shallow(C);
 697   clonemap->set_memory(mem);
 698   clonemap->set_jvms(clonejvms);
 699   clonejvms->set_map(clonemap);
 700   record_for_igvn(clonemap);
 701   gvn().set_type_bottom(clonemap);
 702   return clonemap;
 703 }
 704 
 705 
 706 //-----------------------------set_map_clone-----------------------------------
 707 void GraphKit::set_map_clone(SafePointNode* m) {
 708   _map = m;
 709   _map = clone_map();
 710   _map->set_next_exception(NULL);
 711   debug_only(verify_map());
 712 }
 713 
 714 
 715 //----------------------------kill_dead_locals---------------------------------
 716 // Detect any locals which are known to be dead, and force them to top.
 717 void GraphKit::kill_dead_locals() {
 718   // Consult the liveness information for the locals.  If any
 719   // of them are unused, then they can be replaced by top().  This
 720   // should help register allocation time and cut down on the size
 721   // of the deoptimization information.
 722 
 723   // This call is made from many of the bytecode handling
 724   // subroutines called from the Big Switch in do_one_bytecode.
 725   // Every bytecode which might include a slow path is responsible
 726   // for killing its dead locals.  The more consistent we
 727   // are about killing deads, the fewer useless phis will be
 728   // constructed for them at various merge points.
 729 
 730   // bci can be -1 (InvocationEntryBci).  We return the entry
 731   // liveness for the method.
 732 
 733   if (method() == NULL || method()->code_size() == 0) {
 734     // We are building a graph for a call to a native method.
 735     // All locals are live.
 736     return;
 737   }
 738 
 739   ResourceMark rm;
 740 
 741   // Consult the liveness information for the locals.  If any
 742   // of them are unused, then they can be replaced by top().  This
 743   // should help register allocation time and cut down on the size
 744   // of the deoptimization information.
 745   MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
 746 
 747   int len = (int)live_locals.size();
 748   assert(len <= jvms()->loc_size(), "too many live locals");
 749   for (int local = 0; local < len; local++) {
 750     if (!live_locals.at(local)) {
 751       set_local(local, top());
 752     }
 753   }
 754 }
 755 
 756 #ifdef ASSERT
 757 //-------------------------dead_locals_are_killed------------------------------
 758 // Return true if all dead locals are set to top in the map.
 759 // Used to assert "clean" debug info at various points.
 760 bool GraphKit::dead_locals_are_killed() {
 761   if (method() == NULL || method()->code_size() == 0) {
 762     // No locals need to be dead, so all is as it should be.
 763     return true;
 764   }
 765 
 766   // Make sure somebody called kill_dead_locals upstream.
 767   ResourceMark rm;
 768   for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
 769     if (jvms->loc_size() == 0)  continue;  // no locals to consult
 770     SafePointNode* map = jvms->map();
 771     ciMethod* method = jvms->method();
 772     int       bci    = jvms->bci();
 773     if (jvms == this->jvms()) {
 774       bci = this->bci();  // it might not yet be synched
 775     }
 776     MethodLivenessResult live_locals = method->liveness_at_bci(bci);
 777     int len = (int)live_locals.size();
 778     if (!live_locals.is_valid() || len == 0)
 779       // This method is trivial, or is poisoned by a breakpoint.
 780       return true;
 781     assert(len == jvms->loc_size(), "live map consistent with locals map");
 782     for (int local = 0; local < len; local++) {
 783       if (!live_locals.at(local) && map->local(jvms, local) != top()) {
 784         if (PrintMiscellaneous && (Verbose || WizardMode)) {
 785           tty->print_cr("Zombie local %d: ", local);
 786           jvms->dump();
 787         }
 788         return false;
 789       }
 790     }
 791   }
 792   return true;
 793 }
 794 
 795 #endif //ASSERT
 796 
 797 // Helper function for enforcing certain bytecodes to reexecute if
 798 // deoptimization happens
 799 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
 800   ciMethod* cur_method = jvms->method();
 801   int       cur_bci   = jvms->bci();
 802   if (cur_method != NULL && cur_bci != InvocationEntryBci) {
 803     Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
 804     return Interpreter::bytecode_should_reexecute(code) ||
 805            is_anewarray && code == Bytecodes::_multianewarray;
 806     // Reexecute _multianewarray bytecode which was replaced with
 807     // sequence of [a]newarray. See Parse::do_multianewarray().
 808     //
 809     // Note: interpreter should not have it set since this optimization
 810     // is limited by dimensions and guarded by flag so in some cases
 811     // multianewarray() runtime calls will be generated and
 812     // the bytecode should not be reexecutes (stack will not be reset).
 813   } else
 814     return false;
 815 }
 816 
 817 // Helper function for adding JVMState and debug information to node
 818 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
 819   // Add the safepoint edges to the call (or other safepoint).
 820 
 821   // Make sure dead locals are set to top.  This
 822   // should help register allocation time and cut down on the size
 823   // of the deoptimization information.
 824   assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
 825 
 826   // Walk the inline list to fill in the correct set of JVMState's
 827   // Also fill in the associated edges for each JVMState.
 828 
 829   JVMState* youngest_jvms = sync_jvms();
 830 
 831   // If we are guaranteed to throw, we can prune everything but the
 832   // input to the current bytecode.
 833   bool can_prune_locals = false;
 834   uint stack_slots_not_pruned = 0;
 835   int inputs = 0, depth = 0;
 836   if (must_throw) {
 837     assert(method() == youngest_jvms->method(), "sanity");
 838     if (compute_stack_effects(inputs, depth)) {
 839       can_prune_locals = true;
 840       stack_slots_not_pruned = inputs;
 841     }
 842   }
 843 
 844   if (env()->jvmti_can_access_local_variables()) {
 845     // At any safepoint, this method can get breakpointed, which would
 846     // then require an immediate deoptimization.
 847     can_prune_locals = false;  // do not prune locals
 848     stack_slots_not_pruned = 0;
 849   }
 850 
 851   // do not scribble on the input jvms
 852   JVMState* out_jvms = youngest_jvms->clone_deep(C);
 853   call->set_jvms(out_jvms); // Start jvms list for call node
 854 
 855   // For a known set of bytecodes, the interpreter should reexecute them if
 856   // deoptimization happens. We set the reexecute state for them here
 857   if (out_jvms->is_reexecute_undefined() && //don't change if already specified
 858       should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
 859     out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
 860   }
 861 
 862   // Presize the call:
 863   debug_only(uint non_debug_edges = call->req());
 864   call->add_req_batch(top(), youngest_jvms->debug_depth());
 865   assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
 866 
 867   // Set up edges so that the call looks like this:
 868   //  Call [state:] ctl io mem fptr retadr
 869   //       [parms:] parm0 ... parmN
 870   //       [root:]  loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 871   //    [...mid:]   loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
 872   //       [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 873   // Note that caller debug info precedes callee debug info.
 874 
 875   // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
 876   uint debug_ptr = call->req();
 877 
 878   // Loop over the map input edges associated with jvms, add them
 879   // to the call node, & reset all offsets to match call node array.
 880   for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) {
 881     uint debug_end   = debug_ptr;
 882     uint debug_start = debug_ptr - in_jvms->debug_size();
 883     debug_ptr = debug_start;  // back up the ptr
 884 
 885     uint p = debug_start;  // walks forward in [debug_start, debug_end)
 886     uint j, k, l;
 887     SafePointNode* in_map = in_jvms->map();
 888     out_jvms->set_map(call);
 889 
 890     if (can_prune_locals) {
 891       assert(in_jvms->method() == out_jvms->method(), "sanity");
 892       // If the current throw can reach an exception handler in this JVMS,
 893       // then we must keep everything live that can reach that handler.
 894       // As a quick and dirty approximation, we look for any handlers at all.
 895       if (in_jvms->method()->has_exception_handlers()) {
 896         can_prune_locals = false;
 897       }
 898     }
 899 
 900     // Add the Locals
 901     k = in_jvms->locoff();
 902     l = in_jvms->loc_size();
 903     out_jvms->set_locoff(p);
 904     if (!can_prune_locals) {
 905       for (j = 0; j < l; j++)
 906         call->set_req(p++, in_map->in(k+j));
 907     } else {
 908       p += l;  // already set to top above by add_req_batch
 909     }
 910 
 911     // Add the Expression Stack
 912     k = in_jvms->stkoff();
 913     l = in_jvms->sp();
 914     out_jvms->set_stkoff(p);
 915     if (!can_prune_locals) {
 916       for (j = 0; j < l; j++)
 917         call->set_req(p++, in_map->in(k+j));
 918     } else if (can_prune_locals && stack_slots_not_pruned != 0) {
 919       // Divide stack into {S0,...,S1}, where S0 is set to top.
 920       uint s1 = stack_slots_not_pruned;
 921       stack_slots_not_pruned = 0;  // for next iteration
 922       if (s1 > l)  s1 = l;
 923       uint s0 = l - s1;
 924       p += s0;  // skip the tops preinstalled by add_req_batch
 925       for (j = s0; j < l; j++)
 926         call->set_req(p++, in_map->in(k+j));
 927     } else {
 928       p += l;  // already set to top above by add_req_batch
 929     }
 930 
 931     // Add the Monitors
 932     k = in_jvms->monoff();
 933     l = in_jvms->mon_size();
 934     out_jvms->set_monoff(p);
 935     for (j = 0; j < l; j++)
 936       call->set_req(p++, in_map->in(k+j));
 937 
 938     // Copy any scalar object fields.
 939     k = in_jvms->scloff();
 940     l = in_jvms->scl_size();
 941     out_jvms->set_scloff(p);
 942     for (j = 0; j < l; j++)
 943       call->set_req(p++, in_map->in(k+j));
 944 
 945     // Finish the new jvms.
 946     out_jvms->set_endoff(p);
 947 
 948     assert(out_jvms->endoff()     == debug_end,             "fill ptr must match");
 949     assert(out_jvms->depth()      == in_jvms->depth(),      "depth must match");
 950     assert(out_jvms->loc_size()   == in_jvms->loc_size(),   "size must match");
 951     assert(out_jvms->mon_size()   == in_jvms->mon_size(),   "size must match");
 952     assert(out_jvms->scl_size()   == in_jvms->scl_size(),   "size must match");
 953     assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
 954 
 955     // Update the two tail pointers in parallel.
 956     out_jvms = out_jvms->caller();
 957     in_jvms  = in_jvms->caller();
 958   }
 959 
 960   assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
 961 
 962   // Test the correctness of JVMState::debug_xxx accessors:
 963   assert(call->jvms()->debug_start() == non_debug_edges, "");
 964   assert(call->jvms()->debug_end()   == call->req(), "");
 965   assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
 966 }
 967 
 968 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
 969   Bytecodes::Code code = java_bc();
 970   if (code == Bytecodes::_wide) {
 971     code = method()->java_code_at_bci(bci() + 1);
 972   }
 973 
 974   BasicType rtype = T_ILLEGAL;
 975   int       rsize = 0;
 976 
 977   if (code != Bytecodes::_illegal) {
 978     depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
 979     rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
 980     if (rtype < T_CONFLICT)
 981       rsize = type2size[rtype];
 982   }
 983 
 984   switch (code) {
 985   case Bytecodes::_illegal:
 986     return false;
 987 
 988   case Bytecodes::_ldc:
 989   case Bytecodes::_ldc_w:
 990   case Bytecodes::_ldc2_w:
 991     inputs = 0;
 992     break;
 993 
 994   case Bytecodes::_dup:         inputs = 1;  break;
 995   case Bytecodes::_dup_x1:      inputs = 2;  break;
 996   case Bytecodes::_dup_x2:      inputs = 3;  break;
 997   case Bytecodes::_dup2:        inputs = 2;  break;
 998   case Bytecodes::_dup2_x1:     inputs = 3;  break;
 999   case Bytecodes::_dup2_x2:     inputs = 4;  break;
1000   case Bytecodes::_swap:        inputs = 2;  break;
1001   case Bytecodes::_arraylength: inputs = 1;  break;
1002 
1003   case Bytecodes::_getstatic:
1004   case Bytecodes::_putstatic:
1005   case Bytecodes::_getfield:
1006   case Bytecodes::_putfield:
1007     {
1008       bool is_get = (depth >= 0), is_static = (depth & 1);
1009       bool ignore;
1010       ciBytecodeStream iter(method());
1011       iter.reset_to_bci(bci());
1012       iter.next();
1013       ciField* field = iter.get_field(ignore);
1014       int      size  = field->type()->size();
1015       inputs  = (is_static ? 0 : 1);
1016       if (is_get) {
1017         depth = size - inputs;
1018       } else {
1019         inputs += size;        // putxxx pops the value from the stack
1020         depth = - inputs;
1021       }
1022     }
1023     break;
1024 
1025   case Bytecodes::_invokevirtual:
1026   case Bytecodes::_invokespecial:
1027   case Bytecodes::_invokestatic:
1028   case Bytecodes::_invokedynamic:
1029   case Bytecodes::_invokeinterface:
1030     {
1031       bool ignore;
1032       ciBytecodeStream iter(method());
1033       iter.reset_to_bci(bci());
1034       iter.next();
1035       ciMethod* method = iter.get_method(ignore);
1036       // (Do not use ciMethod::arg_size(), because
1037       // it might be an unloaded method, which doesn't
1038       // know whether it is static or not.)
1039       inputs = method->invoke_arg_size(code);
1040       int size = method->return_type()->size();
1041       depth = size - inputs;
1042     }
1043     break;
1044 
1045   case Bytecodes::_multianewarray:
1046     {
1047       ciBytecodeStream iter(method());
1048       iter.reset_to_bci(bci());
1049       iter.next();
1050       inputs = iter.get_dimensions();
1051       assert(rsize == 1, "");
1052       depth = rsize - inputs;
1053     }
1054     break;
1055 
1056   case Bytecodes::_ireturn:
1057   case Bytecodes::_lreturn:
1058   case Bytecodes::_freturn:
1059   case Bytecodes::_dreturn:
1060   case Bytecodes::_areturn:
1061     assert(rsize = -depth, "");
1062     inputs = rsize;
1063     break;
1064 
1065   case Bytecodes::_jsr:
1066   case Bytecodes::_jsr_w:
1067     inputs = 0;
1068     depth  = 1;                  // S.B. depth=1, not zero
1069     break;
1070 
1071   default:
1072     // bytecode produces a typed result
1073     inputs = rsize - depth;
1074     assert(inputs >= 0, "");
1075     break;
1076   }
1077 
1078 #ifdef ASSERT
1079   // spot check
1080   int outputs = depth + inputs;
1081   assert(outputs >= 0, "sanity");
1082   switch (code) {
1083   case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1084   case Bytecodes::_athrow:    assert(inputs == 1 && outputs == 0, ""); break;
1085   case Bytecodes::_aload_0:   assert(inputs == 0 && outputs == 1, ""); break;
1086   case Bytecodes::_return:    assert(inputs == 0 && outputs == 0, ""); break;
1087   case Bytecodes::_drem:      assert(inputs == 4 && outputs == 2, ""); break;
1088   }
1089 #endif //ASSERT
1090 
1091   return true;
1092 }
1093 
1094 
1095 
1096 //------------------------------basic_plus_adr---------------------------------
1097 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1098   // short-circuit a common case
1099   if (offset == intcon(0))  return ptr;
1100   return _gvn.transform( new (C, 4) AddPNode(base, ptr, offset) );
1101 }
1102 
1103 Node* GraphKit::ConvI2L(Node* offset) {
1104   // short-circuit a common case
1105   jint offset_con = find_int_con(offset, Type::OffsetBot);
1106   if (offset_con != Type::OffsetBot) {
1107     return longcon((long) offset_con);
1108   }
1109   return _gvn.transform( new (C, 2) ConvI2LNode(offset));
1110 }
1111 Node* GraphKit::ConvL2I(Node* offset) {
1112   // short-circuit a common case
1113   jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1114   if (offset_con != (jlong)Type::OffsetBot) {
1115     return intcon((int) offset_con);
1116   }
1117   return _gvn.transform( new (C, 2) ConvL2INode(offset));
1118 }
1119 
1120 //-------------------------load_object_klass-----------------------------------
1121 Node* GraphKit::load_object_klass(Node* obj) {
1122   // Special-case a fresh allocation to avoid building nodes:
1123   Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1124   if (akls != NULL)  return akls;
1125   Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1126   return _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), k_adr, TypeInstPtr::KLASS) );
1127 }
1128 
1129 //-------------------------load_array_length-----------------------------------
1130 Node* GraphKit::load_array_length(Node* array) {
1131   // Special-case a fresh allocation to avoid building nodes:
1132   AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn);
1133   Node *alen;
1134   if (alloc == NULL) {
1135     Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1136     alen = _gvn.transform( new (C, 3) LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1137   } else {
1138     alen = alloc->Ideal_length();
1139     Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn);
1140     if (ccast != alen) {
1141       alen = _gvn.transform(ccast);
1142     }
1143   }
1144   return alen;
1145 }
1146 
1147 //------------------------------do_null_check----------------------------------
1148 // Helper function to do a NULL pointer check.  Returned value is
1149 // the incoming address with NULL casted away.  You are allowed to use the
1150 // not-null value only if you are control dependent on the test.
1151 extern int explicit_null_checks_inserted,
1152            explicit_null_checks_elided;
1153 Node* GraphKit::null_check_common(Node* value, BasicType type,
1154                                   // optional arguments for variations:
1155                                   bool assert_null,
1156                                   Node* *null_control) {
1157   assert(!assert_null || null_control == NULL, "not both at once");
1158   if (stopped())  return top();
1159   if (!GenerateCompilerNullChecks && !assert_null && null_control == NULL) {
1160     // For some performance testing, we may wish to suppress null checking.
1161     value = cast_not_null(value);   // Make it appear to be non-null (4962416).
1162     return value;
1163   }
1164   explicit_null_checks_inserted++;
1165 
1166   // Construct NULL check
1167   Node *chk = NULL;
1168   switch(type) {
1169     case T_LONG   : chk = new (C, 3) CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1170     case T_INT    : chk = new (C, 3) CmpINode( value, _gvn.intcon(0)); break;
1171     case T_ARRAY  : // fall through
1172       type = T_OBJECT;  // simplify further tests
1173     case T_OBJECT : {
1174       const Type *t = _gvn.type( value );
1175 
1176       const TypeOopPtr* tp = t->isa_oopptr();
1177       if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded()
1178           // Only for do_null_check, not any of its siblings:
1179           && !assert_null && null_control == NULL) {
1180         // Usually, any field access or invocation on an unloaded oop type
1181         // will simply fail to link, since the statically linked class is
1182         // likely also to be unloaded.  However, in -Xcomp mode, sometimes
1183         // the static class is loaded but the sharper oop type is not.
1184         // Rather than checking for this obscure case in lots of places,
1185         // we simply observe that a null check on an unloaded class
1186         // will always be followed by a nonsense operation, so we
1187         // can just issue the uncommon trap here.
1188         // Our access to the unloaded class will only be correct
1189         // after it has been loaded and initialized, which requires
1190         // a trip through the interpreter.
1191 #ifndef PRODUCT
1192         if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); }
1193 #endif
1194         uncommon_trap(Deoptimization::Reason_unloaded,
1195                       Deoptimization::Action_reinterpret,
1196                       tp->klass(), "!loaded");
1197         return top();
1198       }
1199 
1200       if (assert_null) {
1201         // See if the type is contained in NULL_PTR.
1202         // If so, then the value is already null.
1203         if (t->higher_equal(TypePtr::NULL_PTR)) {
1204           explicit_null_checks_elided++;
1205           return value;           // Elided null assert quickly!
1206         }
1207       } else {
1208         // See if mixing in the NULL pointer changes type.
1209         // If so, then the NULL pointer was not allowed in the original
1210         // type.  In other words, "value" was not-null.
1211         if (t->meet(TypePtr::NULL_PTR) != t) {
1212           // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1213           explicit_null_checks_elided++;
1214           return value;           // Elided null check quickly!
1215         }
1216       }
1217       chk = new (C, 3) CmpPNode( value, null() );
1218       break;
1219     }
1220 
1221     default      : ShouldNotReachHere();
1222   }
1223   assert(chk != NULL, "sanity check");
1224   chk = _gvn.transform(chk);
1225 
1226   BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1227   BoolNode *btst = new (C, 2) BoolNode( chk, btest);
1228   Node   *tst = _gvn.transform( btst );
1229 
1230   //-----------
1231   // if peephole optimizations occurred, a prior test existed.
1232   // If a prior test existed, maybe it dominates as we can avoid this test.
1233   if (tst != btst && type == T_OBJECT) {
1234     // At this point we want to scan up the CFG to see if we can
1235     // find an identical test (and so avoid this test altogether).
1236     Node *cfg = control();
1237     int depth = 0;
1238     while( depth < 16 ) {       // Limit search depth for speed
1239       if( cfg->Opcode() == Op_IfTrue &&
1240           cfg->in(0)->in(1) == tst ) {
1241         // Found prior test.  Use "cast_not_null" to construct an identical
1242         // CastPP (and hence hash to) as already exists for the prior test.
1243         // Return that casted value.
1244         if (assert_null) {
1245           replace_in_map(value, null());
1246           return null();  // do not issue the redundant test
1247         }
1248         Node *oldcontrol = control();
1249         set_control(cfg);
1250         Node *res = cast_not_null(value);
1251         set_control(oldcontrol);
1252         explicit_null_checks_elided++;
1253         return res;
1254       }
1255       cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1256       if (cfg == NULL)  break;  // Quit at region nodes
1257       depth++;
1258     }
1259   }
1260 
1261   //-----------
1262   // Branch to failure if null
1263   float ok_prob = PROB_MAX;  // a priori estimate:  nulls never happen
1264   Deoptimization::DeoptReason reason;
1265   if (assert_null)
1266     reason = Deoptimization::Reason_null_assert;
1267   else if (type == T_OBJECT)
1268     reason = Deoptimization::Reason_null_check;
1269   else
1270     reason = Deoptimization::Reason_div0_check;
1271 
1272   // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1273   // ciMethodData::has_trap_at will return a conservative -1 if any
1274   // must-be-null assertion has failed.  This could cause performance
1275   // problems for a method after its first do_null_assert failure.
1276   // Consider using 'Reason_class_check' instead?
1277 
1278   // To cause an implicit null check, we set the not-null probability
1279   // to the maximum (PROB_MAX).  For an explicit check the probability
1280   // is set to a smaller value.
1281   if (null_control != NULL || too_many_traps(reason)) {
1282     // probability is less likely
1283     ok_prob =  PROB_LIKELY_MAG(3);
1284   } else if (!assert_null &&
1285              (ImplicitNullCheckThreshold > 0) &&
1286              method() != NULL &&
1287              (method()->method_data()->trap_count(reason)
1288               >= (uint)ImplicitNullCheckThreshold)) {
1289     ok_prob =  PROB_LIKELY_MAG(3);
1290   }
1291 
1292   if (null_control != NULL) {
1293     IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1294     Node* null_true = _gvn.transform( new (C, 1) IfFalseNode(iff));
1295     set_control(      _gvn.transform( new (C, 1) IfTrueNode(iff)));
1296     if (null_true == top())
1297       explicit_null_checks_elided++;
1298     (*null_control) = null_true;
1299   } else {
1300     BuildCutout unless(this, tst, ok_prob);
1301     // Check for optimizer eliding test at parse time
1302     if (stopped()) {
1303       // Failure not possible; do not bother making uncommon trap.
1304       explicit_null_checks_elided++;
1305     } else if (assert_null) {
1306       uncommon_trap(reason,
1307                     Deoptimization::Action_make_not_entrant,
1308                     NULL, "assert_null");
1309     } else {
1310       replace_in_map(value, zerocon(type));
1311       builtin_throw(reason);
1312     }
1313   }
1314 
1315   // Must throw exception, fall-thru not possible?
1316   if (stopped()) {
1317     return top();               // No result
1318   }
1319 
1320   if (assert_null) {
1321     // Cast obj to null on this path.
1322     replace_in_map(value, zerocon(type));
1323     return zerocon(type);
1324   }
1325 
1326   // Cast obj to not-null on this path, if there is no null_control.
1327   // (If there is a null_control, a non-null value may come back to haunt us.)
1328   if (type == T_OBJECT) {
1329     Node* cast = cast_not_null(value, false);
1330     if (null_control == NULL || (*null_control) == top())
1331       replace_in_map(value, cast);
1332     value = cast;
1333   }
1334 
1335   return value;
1336 }
1337 
1338 
1339 //------------------------------cast_not_null----------------------------------
1340 // Cast obj to not-null on this path
1341 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1342   const Type *t = _gvn.type(obj);
1343   const Type *t_not_null = t->join(TypePtr::NOTNULL);
1344   // Object is already not-null?
1345   if( t == t_not_null ) return obj;
1346 
1347   Node *cast = new (C, 2) CastPPNode(obj,t_not_null);
1348   cast->init_req(0, control());
1349   cast = _gvn.transform( cast );
1350 
1351   // Scan for instances of 'obj' in the current JVM mapping.
1352   // These instances are known to be not-null after the test.
1353   if (do_replace_in_map)
1354     replace_in_map(obj, cast);
1355 
1356   return cast;                  // Return casted value
1357 }
1358 
1359 
1360 //--------------------------replace_in_map-------------------------------------
1361 void GraphKit::replace_in_map(Node* old, Node* neww) {
1362   this->map()->replace_edge(old, neww);
1363 
1364   // Note: This operation potentially replaces any edge
1365   // on the map.  This includes locals, stack, and monitors
1366   // of the current (innermost) JVM state.
1367 
1368   // We can consider replacing in caller maps.
1369   // The idea would be that an inlined function's null checks
1370   // can be shared with the entire inlining tree.
1371   // The expense of doing this is that the PreserveJVMState class
1372   // would have to preserve caller states too, with a deep copy.
1373 }
1374 
1375 
1376 
1377 //=============================================================================
1378 //--------------------------------memory---------------------------------------
1379 Node* GraphKit::memory(uint alias_idx) {
1380   MergeMemNode* mem = merged_memory();
1381   Node* p = mem->memory_at(alias_idx);
1382   _gvn.set_type(p, Type::MEMORY);  // must be mapped
1383   return p;
1384 }
1385 
1386 //-----------------------------reset_memory------------------------------------
1387 Node* GraphKit::reset_memory() {
1388   Node* mem = map()->memory();
1389   // do not use this node for any more parsing!
1390   debug_only( map()->set_memory((Node*)NULL) );
1391   return _gvn.transform( mem );
1392 }
1393 
1394 //------------------------------set_all_memory---------------------------------
1395 void GraphKit::set_all_memory(Node* newmem) {
1396   Node* mergemem = MergeMemNode::make(C, newmem);
1397   gvn().set_type_bottom(mergemem);
1398   map()->set_memory(mergemem);
1399 }
1400 
1401 //------------------------------set_all_memory_call----------------------------
1402 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1403   Node* newmem = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1404   set_all_memory(newmem);
1405 }
1406 
1407 //=============================================================================
1408 //
1409 // parser factory methods for MemNodes
1410 //
1411 // These are layered on top of the factory methods in LoadNode and StoreNode,
1412 // and integrate with the parser's memory state and _gvn engine.
1413 //
1414 
1415 // factory methods in "int adr_idx"
1416 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1417                           int adr_idx,
1418                           bool require_atomic_access) {
1419   assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1420   const TypePtr* adr_type = NULL; // debug-mode-only argument
1421   debug_only(adr_type = C->get_adr_type(adr_idx));
1422   Node* mem = memory(adr_idx);
1423   Node* ld;
1424   if (require_atomic_access && bt == T_LONG) {
1425     ld = LoadLNode::make_atomic(C, ctl, mem, adr, adr_type, t);
1426   } else {
1427     ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt);
1428   }
1429   return _gvn.transform(ld);
1430 }
1431 
1432 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1433                                 int adr_idx,
1434                                 bool require_atomic_access) {
1435   assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1436   const TypePtr* adr_type = NULL;
1437   debug_only(adr_type = C->get_adr_type(adr_idx));
1438   Node *mem = memory(adr_idx);
1439   Node* st;
1440   if (require_atomic_access && bt == T_LONG) {
1441     st = StoreLNode::make_atomic(C, ctl, mem, adr, adr_type, val);
1442   } else {
1443     st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt);
1444   }
1445   st = _gvn.transform(st);
1446   set_memory(st, adr_idx);
1447   // Back-to-back stores can only remove intermediate store with DU info
1448   // so push on worklist for optimizer.
1449   if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1450     record_for_igvn(st);
1451 
1452   return st;
1453 }
1454 
1455 
1456 void GraphKit::pre_barrier(bool do_load,
1457                            Node* ctl,
1458                            Node* obj,
1459                            Node* adr,
1460                            uint  adr_idx,
1461                            Node* val,
1462                            const TypeOopPtr* val_type,
1463                            Node* pre_val,
1464                            BasicType bt) {
1465 
1466   BarrierSet* bs = Universe::heap()->barrier_set();
1467   set_control(ctl);
1468   switch (bs->kind()) {
1469     case BarrierSet::G1SATBCT:
1470     case BarrierSet::G1SATBCTLogging:
1471       g1_write_barrier_pre(do_load, obj, adr, adr_idx, val, val_type, pre_val, bt);
1472       break;
1473 
1474     case BarrierSet::CardTableModRef:
1475     case BarrierSet::CardTableExtension:
1476     case BarrierSet::ModRef:
1477       break;
1478 
1479     case BarrierSet::Other:
1480     default      :
1481       ShouldNotReachHere();
1482 
1483   }
1484 }
1485 
1486 void GraphKit::post_barrier(Node* ctl,
1487                             Node* store,
1488                             Node* obj,
1489                             Node* adr,
1490                             uint  adr_idx,
1491                             Node* val,
1492                             BasicType bt,
1493                             bool use_precise) {
1494   BarrierSet* bs = Universe::heap()->barrier_set();
1495   set_control(ctl);
1496   switch (bs->kind()) {
1497     case BarrierSet::G1SATBCT:
1498     case BarrierSet::G1SATBCTLogging:
1499       g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise);
1500       break;
1501 
1502     case BarrierSet::CardTableModRef:
1503     case BarrierSet::CardTableExtension:
1504       write_barrier_post(store, obj, adr, adr_idx, val, use_precise);
1505       break;
1506 
1507     case BarrierSet::ModRef:
1508       break;
1509 
1510     case BarrierSet::Other:
1511     default      :
1512       ShouldNotReachHere();
1513 
1514   }
1515 }
1516 
1517 Node* GraphKit::store_oop(Node* ctl,
1518                           Node* obj,
1519                           Node* adr,
1520                           const TypePtr* adr_type,
1521                           Node* val,
1522                           const TypeOopPtr* val_type,
1523                           BasicType bt,
1524                           bool use_precise) {
1525 
1526   set_control(ctl);
1527   if (stopped()) return top(); // Dead path ?
1528 
1529   assert(bt == T_OBJECT, "sanity");
1530   assert(val != NULL, "not dead path");
1531   uint adr_idx = C->get_alias_index(adr_type);
1532   assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1533 
1534   pre_barrier(true /* do_load */,
1535               control(), obj, adr, adr_idx, val, val_type,
1536               NULL /* pre_val */,
1537               bt);
1538 
1539   Node* store = store_to_memory(control(), adr, val, bt, adr_idx);
1540   post_barrier(control(), store, obj, adr, adr_idx, val, bt, use_precise);
1541   return store;
1542 }
1543 
1544 // Could be an array or object we don't know at compile time (unsafe ref.)
1545 Node* GraphKit::store_oop_to_unknown(Node* ctl,
1546                              Node* obj,   // containing obj
1547                              Node* adr,  // actual adress to store val at
1548                              const TypePtr* adr_type,
1549                              Node* val,
1550                              BasicType bt) {
1551   Compile::AliasType* at = C->alias_type(adr_type);
1552   const TypeOopPtr* val_type = NULL;
1553   if (adr_type->isa_instptr()) {
1554     if (at->field() != NULL) {
1555       // known field.  This code is a copy of the do_put_xxx logic.
1556       ciField* field = at->field();
1557       if (!field->type()->is_loaded()) {
1558         val_type = TypeInstPtr::BOTTOM;
1559       } else {
1560         val_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
1561       }
1562     }
1563   } else if (adr_type->isa_aryptr()) {
1564     val_type = adr_type->is_aryptr()->elem()->make_oopptr();
1565   }
1566   if (val_type == NULL) {
1567     val_type = TypeInstPtr::BOTTOM;
1568   }
1569   return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true);
1570 }
1571 
1572 
1573 //-------------------------array_element_address-------------------------
1574 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1575                                       const TypeInt* sizetype) {
1576   uint shift  = exact_log2(type2aelembytes(elembt));
1577   uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1578 
1579   // short-circuit a common case (saves lots of confusing waste motion)
1580   jint idx_con = find_int_con(idx, -1);
1581   if (idx_con >= 0) {
1582     intptr_t offset = header + ((intptr_t)idx_con << shift);
1583     return basic_plus_adr(ary, offset);
1584   }
1585 
1586   // must be correct type for alignment purposes
1587   Node* base  = basic_plus_adr(ary, header);
1588 #ifdef _LP64
1589   // The scaled index operand to AddP must be a clean 64-bit value.
1590   // Java allows a 32-bit int to be incremented to a negative
1591   // value, which appears in a 64-bit register as a large
1592   // positive number.  Using that large positive number as an
1593   // operand in pointer arithmetic has bad consequences.
1594   // On the other hand, 32-bit overflow is rare, and the possibility
1595   // can often be excluded, if we annotate the ConvI2L node with
1596   // a type assertion that its value is known to be a small positive
1597   // number.  (The prior range check has ensured this.)
1598   // This assertion is used by ConvI2LNode::Ideal.
1599   int index_max = max_jint - 1;  // array size is max_jint, index is one less
1600   if (sizetype != NULL)  index_max = sizetype->_hi - 1;
1601   const TypeLong* lidxtype = TypeLong::make(CONST64(0), index_max, Type::WidenMax);
1602   idx = _gvn.transform( new (C, 2) ConvI2LNode(idx, lidxtype) );
1603 #endif
1604   Node* scale = _gvn.transform( new (C, 3) LShiftXNode(idx, intcon(shift)) );
1605   return basic_plus_adr(ary, base, scale);
1606 }
1607 
1608 //-------------------------load_array_element-------------------------
1609 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) {
1610   const Type* elemtype = arytype->elem();
1611   BasicType elembt = elemtype->array_element_basic_type();
1612   Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1613   Node* ld = make_load(ctl, adr, elemtype, elembt, arytype);
1614   return ld;
1615 }
1616 
1617 //-------------------------set_arguments_for_java_call-------------------------
1618 // Arguments (pre-popped from the stack) are taken from the JVMS.
1619 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1620   // Add the call arguments:
1621   uint nargs = call->method()->arg_size();
1622   for (uint i = 0; i < nargs; i++) {
1623     Node* arg = argument(i);
1624     call->init_req(i + TypeFunc::Parms, arg);
1625   }
1626 }
1627 
1628 //---------------------------set_edges_for_java_call---------------------------
1629 // Connect a newly created call into the current JVMS.
1630 // A return value node (if any) is returned from set_edges_for_java_call.
1631 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1632 
1633   // Add the predefined inputs:
1634   call->init_req( TypeFunc::Control, control() );
1635   call->init_req( TypeFunc::I_O    , i_o() );
1636   call->init_req( TypeFunc::Memory , reset_memory() );
1637   call->init_req( TypeFunc::FramePtr, frameptr() );
1638   call->init_req( TypeFunc::ReturnAdr, top() );
1639 
1640   add_safepoint_edges(call, must_throw);
1641 
1642   Node* xcall = _gvn.transform(call);
1643 
1644   if (xcall == top()) {
1645     set_control(top());
1646     return;
1647   }
1648   assert(xcall == call, "call identity is stable");
1649 
1650   // Re-use the current map to produce the result.
1651 
1652   set_control(_gvn.transform(new (C, 1) ProjNode(call, TypeFunc::Control)));
1653   set_i_o(    _gvn.transform(new (C, 1) ProjNode(call, TypeFunc::I_O    , separate_io_proj)));
1654   set_all_memory_call(xcall, separate_io_proj);
1655 
1656   //return xcall;   // no need, caller already has it
1657 }
1658 
1659 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) {
1660   if (stopped())  return top();  // maybe the call folded up?
1661 
1662   // Capture the return value, if any.
1663   Node* ret;
1664   if (call->method() == NULL ||
1665       call->method()->return_type()->basic_type() == T_VOID)
1666         ret = top();
1667   else  ret = _gvn.transform(new (C, 1) ProjNode(call, TypeFunc::Parms));
1668 
1669   // Note:  Since any out-of-line call can produce an exception,
1670   // we always insert an I_O projection from the call into the result.
1671 
1672   make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj);
1673 
1674   if (separate_io_proj) {
1675     // The caller requested separate projections be used by the fall
1676     // through and exceptional paths, so replace the projections for
1677     // the fall through path.
1678     set_i_o(_gvn.transform( new (C, 1) ProjNode(call, TypeFunc::I_O) ));
1679     set_all_memory(_gvn.transform( new (C, 1) ProjNode(call, TypeFunc::Memory) ));
1680   }
1681   return ret;
1682 }
1683 
1684 //--------------------set_predefined_input_for_runtime_call--------------------
1685 // Reading and setting the memory state is way conservative here.
1686 // The real problem is that I am not doing real Type analysis on memory,
1687 // so I cannot distinguish card mark stores from other stores.  Across a GC
1688 // point the Store Barrier and the card mark memory has to agree.  I cannot
1689 // have a card mark store and its barrier split across the GC point from
1690 // either above or below.  Here I get that to happen by reading ALL of memory.
1691 // A better answer would be to separate out card marks from other memory.
1692 // For now, return the input memory state, so that it can be reused
1693 // after the call, if this call has restricted memory effects.
1694 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) {
1695   // Set fixed predefined input arguments
1696   Node* memory = reset_memory();
1697   call->init_req( TypeFunc::Control,   control()  );
1698   call->init_req( TypeFunc::I_O,       top()      ); // does no i/o
1699   call->init_req( TypeFunc::Memory,    memory     ); // may gc ptrs
1700   call->init_req( TypeFunc::FramePtr,  frameptr() );
1701   call->init_req( TypeFunc::ReturnAdr, top()      );
1702   return memory;
1703 }
1704 
1705 //-------------------set_predefined_output_for_runtime_call--------------------
1706 // Set control and memory (not i_o) from the call.
1707 // If keep_mem is not NULL, use it for the output state,
1708 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1709 // If hook_mem is NULL, this call produces no memory effects at all.
1710 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1711 // then only that memory slice is taken from the call.
1712 // In the last case, we must put an appropriate memory barrier before
1713 // the call, so as to create the correct anti-dependencies on loads
1714 // preceding the call.
1715 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1716                                                       Node* keep_mem,
1717                                                       const TypePtr* hook_mem) {
1718   // no i/o
1719   set_control(_gvn.transform( new (C, 1) ProjNode(call,TypeFunc::Control) ));
1720   if (keep_mem) {
1721     // First clone the existing memory state
1722     set_all_memory(keep_mem);
1723     if (hook_mem != NULL) {
1724       // Make memory for the call
1725       Node* mem = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::Memory) );
1726       // Set the RawPtr memory state only.  This covers all the heap top/GC stuff
1727       // We also use hook_mem to extract specific effects from arraycopy stubs.
1728       set_memory(mem, hook_mem);
1729     }
1730     // ...else the call has NO memory effects.
1731 
1732     // Make sure the call advertises its memory effects precisely.
1733     // This lets us build accurate anti-dependences in gcm.cpp.
1734     assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1735            "call node must be constructed correctly");
1736   } else {
1737     assert(hook_mem == NULL, "");
1738     // This is not a "slow path" call; all memory comes from the call.
1739     set_all_memory_call(call);
1740   }
1741 }
1742 
1743 
1744 // Replace the call with the current state of the kit.
1745 void GraphKit::replace_call(CallNode* call, Node* result) {
1746   JVMState* ejvms = NULL;
1747   if (has_exceptions()) {
1748     ejvms = transfer_exceptions_into_jvms();
1749   }
1750 
1751   SafePointNode* final_state = stop();
1752 
1753   // Find all the needed outputs of this call
1754   CallProjections callprojs;
1755   call->extract_projections(&callprojs, true);
1756 
1757   // Replace all the old call edges with the edges from the inlining result
1758   C->gvn_replace_by(callprojs.fallthrough_catchproj, final_state->in(TypeFunc::Control));
1759   C->gvn_replace_by(callprojs.fallthrough_memproj,   final_state->in(TypeFunc::Memory));
1760   C->gvn_replace_by(callprojs.fallthrough_ioproj,    final_state->in(TypeFunc::I_O));
1761   Node* final_mem = final_state->in(TypeFunc::Memory);
1762 
1763   // Replace the result with the new result if it exists and is used
1764   if (callprojs.resproj != NULL && result != NULL) {
1765     C->gvn_replace_by(callprojs.resproj, result);
1766   }
1767 
1768   if (ejvms == NULL) {
1769     // No exception edges to simply kill off those paths
1770     C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1771     C->gvn_replace_by(callprojs.catchall_memproj,   C->top());
1772     C->gvn_replace_by(callprojs.catchall_ioproj,    C->top());
1773 
1774     // Replace the old exception object with top
1775     if (callprojs.exobj != NULL) {
1776       C->gvn_replace_by(callprojs.exobj, C->top());
1777     }
1778   } else {
1779     GraphKit ekit(ejvms);
1780 
1781     // Load my combined exception state into the kit, with all phis transformed:
1782     SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1783 
1784     Node* ex_oop = ekit.use_exception_state(ex_map);
1785 
1786     C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1787     C->gvn_replace_by(callprojs.catchall_memproj,   ekit.reset_memory());
1788     C->gvn_replace_by(callprojs.catchall_ioproj,    ekit.i_o());
1789 
1790     // Replace the old exception object with the newly created one
1791     if (callprojs.exobj != NULL) {
1792       C->gvn_replace_by(callprojs.exobj, ex_oop);
1793     }
1794   }
1795 
1796   // Disconnect the call from the graph
1797   call->disconnect_inputs(NULL);
1798   C->gvn_replace_by(call, C->top());
1799 
1800   // Clean up any MergeMems that feed other MergeMems since the
1801   // optimizer doesn't like that.
1802   if (final_mem->is_MergeMem()) {
1803     Node_List wl;
1804     for (SimpleDUIterator i(final_mem); i.has_next(); i.next()) {
1805       Node* m = i.get();
1806       if (m->is_MergeMem() && !wl.contains(m)) {
1807         wl.push(m);
1808       }
1809     }
1810     while (wl.size()  > 0) {
1811       _gvn.transform(wl.pop());
1812     }
1813   }
1814 }
1815 
1816 
1817 //------------------------------increment_counter------------------------------
1818 // for statistics: increment a VM counter by 1
1819 
1820 void GraphKit::increment_counter(address counter_addr) {
1821   Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
1822   increment_counter(adr1);
1823 }
1824 
1825 void GraphKit::increment_counter(Node* counter_addr) {
1826   int adr_type = Compile::AliasIdxRaw;
1827   Node* ctrl = control();
1828   Node* cnt  = make_load(ctrl, counter_addr, TypeInt::INT, T_INT, adr_type);
1829   Node* incr = _gvn.transform(new (C, 3) AddINode(cnt, _gvn.intcon(1)));
1830   store_to_memory( ctrl, counter_addr, incr, T_INT, adr_type );
1831 }
1832 
1833 
1834 //------------------------------uncommon_trap----------------------------------
1835 // Bail out to the interpreter in mid-method.  Implemented by calling the
1836 // uncommon_trap blob.  This helper function inserts a runtime call with the
1837 // right debug info.
1838 void GraphKit::uncommon_trap(int trap_request,
1839                              ciKlass* klass, const char* comment,
1840                              bool must_throw,
1841                              bool keep_exact_action) {
1842   if (failing())  stop();
1843   if (stopped())  return; // trap reachable?
1844 
1845   // Note:  If ProfileTraps is true, and if a deopt. actually
1846   // occurs here, the runtime will make sure an MDO exists.  There is
1847   // no need to call method()->ensure_method_data() at this point.
1848 
1849 #ifdef ASSERT
1850   if (!must_throw) {
1851     // Make sure the stack has at least enough depth to execute
1852     // the current bytecode.
1853     int inputs, ignore;
1854     if (compute_stack_effects(inputs, ignore)) {
1855       assert(sp() >= inputs, "must have enough JVMS stack to execute");
1856       // It is a frequent error in library_call.cpp to issue an
1857       // uncommon trap with the _sp value already popped.
1858     }
1859   }
1860 #endif
1861 
1862   Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
1863   Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
1864 
1865   switch (action) {
1866   case Deoptimization::Action_maybe_recompile:
1867   case Deoptimization::Action_reinterpret:
1868     // Temporary fix for 6529811 to allow virtual calls to be sure they
1869     // get the chance to go from mono->bi->mega
1870     if (!keep_exact_action &&
1871         Deoptimization::trap_request_index(trap_request) < 0 &&
1872         too_many_recompiles(reason)) {
1873       // This BCI is causing too many recompilations.
1874       action = Deoptimization::Action_none;
1875       trap_request = Deoptimization::make_trap_request(reason, action);
1876     } else {
1877       C->set_trap_can_recompile(true);
1878     }
1879     break;
1880   case Deoptimization::Action_make_not_entrant:
1881     C->set_trap_can_recompile(true);
1882     break;
1883 #ifdef ASSERT
1884   case Deoptimization::Action_none:
1885   case Deoptimization::Action_make_not_compilable:
1886     break;
1887   default:
1888     assert(false, "bad action");
1889 #endif
1890   }
1891 
1892   if (TraceOptoParse) {
1893     char buf[100];
1894     tty->print_cr("Uncommon trap %s at bci:%d",
1895                   Deoptimization::format_trap_request(buf, sizeof(buf),
1896                                                       trap_request), bci());
1897   }
1898 
1899   CompileLog* log = C->log();
1900   if (log != NULL) {
1901     int kid = (klass == NULL)? -1: log->identify(klass);
1902     log->begin_elem("uncommon_trap bci='%d'", bci());
1903     char buf[100];
1904     log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
1905                                                           trap_request));
1906     if (kid >= 0)         log->print(" klass='%d'", kid);
1907     if (comment != NULL)  log->print(" comment='%s'", comment);
1908     log->end_elem();
1909   }
1910 
1911   // Make sure any guarding test views this path as very unlikely
1912   Node *i0 = control()->in(0);
1913   if (i0 != NULL && i0->is_If()) {        // Found a guarding if test?
1914     IfNode *iff = i0->as_If();
1915     float f = iff->_prob;   // Get prob
1916     if (control()->Opcode() == Op_IfTrue) {
1917       if (f > PROB_UNLIKELY_MAG(4))
1918         iff->_prob = PROB_MIN;
1919     } else {
1920       if (f < PROB_LIKELY_MAG(4))
1921         iff->_prob = PROB_MAX;
1922     }
1923   }
1924 
1925   // Clear out dead values from the debug info.
1926   kill_dead_locals();
1927 
1928   // Now insert the uncommon trap subroutine call
1929   address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point();
1930   const TypePtr* no_memory_effects = NULL;
1931   // Pass the index of the class to be loaded
1932   Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
1933                                  (must_throw ? RC_MUST_THROW : 0),
1934                                  OptoRuntime::uncommon_trap_Type(),
1935                                  call_addr, "uncommon_trap", no_memory_effects,
1936                                  intcon(trap_request));
1937   assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
1938          "must extract request correctly from the graph");
1939   assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
1940 
1941   call->set_req(TypeFunc::ReturnAdr, returnadr());
1942   // The debug info is the only real input to this call.
1943 
1944   // Halt-and-catch fire here.  The above call should never return!
1945   HaltNode* halt = new(C, TypeFunc::Parms) HaltNode(control(), frameptr());
1946   _gvn.set_type_bottom(halt);
1947   root()->add_req(halt);
1948 
1949   stop_and_kill_map();
1950 }
1951 
1952 
1953 //--------------------------just_allocated_object------------------------------
1954 // Report the object that was just allocated.
1955 // It must be the case that there are no intervening safepoints.
1956 // We use this to determine if an object is so "fresh" that
1957 // it does not require card marks.
1958 Node* GraphKit::just_allocated_object(Node* current_control) {
1959   if (C->recent_alloc_ctl() == current_control)
1960     return C->recent_alloc_obj();
1961   return NULL;
1962 }
1963 
1964 
1965 void GraphKit::round_double_arguments(ciMethod* dest_method) {
1966   // (Note:  TypeFunc::make has a cache that makes this fast.)
1967   const TypeFunc* tf    = TypeFunc::make(dest_method);
1968   int             nargs = tf->_domain->_cnt - TypeFunc::Parms;
1969   for (int j = 0; j < nargs; j++) {
1970     const Type *targ = tf->_domain->field_at(j + TypeFunc::Parms);
1971     if( targ->basic_type() == T_DOUBLE ) {
1972       // If any parameters are doubles, they must be rounded before
1973       // the call, dstore_rounding does gvn.transform
1974       Node *arg = argument(j);
1975       arg = dstore_rounding(arg);
1976       set_argument(j, arg);
1977     }
1978   }
1979 }
1980 
1981 void GraphKit::round_double_result(ciMethod* dest_method) {
1982   // A non-strict method may return a double value which has an extended
1983   // exponent, but this must not be visible in a caller which is 'strict'
1984   // If a strict caller invokes a non-strict callee, round a double result
1985 
1986   BasicType result_type = dest_method->return_type()->basic_type();
1987   assert( method() != NULL, "must have caller context");
1988   if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) {
1989     // Destination method's return value is on top of stack
1990     // dstore_rounding() does gvn.transform
1991     Node *result = pop_pair();
1992     result = dstore_rounding(result);
1993     push_pair(result);
1994   }
1995 }
1996 
1997 // rounding for strict float precision conformance
1998 Node* GraphKit::precision_rounding(Node* n) {
1999   return UseStrictFP && _method->flags().is_strict()
2000     && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding
2001     ? _gvn.transform( new (C, 2) RoundFloatNode(0, n) )
2002     : n;
2003 }
2004 
2005 // rounding for strict double precision conformance
2006 Node* GraphKit::dprecision_rounding(Node *n) {
2007   return UseStrictFP && _method->flags().is_strict()
2008     && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding
2009     ? _gvn.transform( new (C, 2) RoundDoubleNode(0, n) )
2010     : n;
2011 }
2012 
2013 // rounding for non-strict double stores
2014 Node* GraphKit::dstore_rounding(Node* n) {
2015   return Matcher::strict_fp_requires_explicit_rounding
2016     && UseSSE <= 1
2017     ? _gvn.transform( new (C, 2) RoundDoubleNode(0, n) )
2018     : n;
2019 }
2020 
2021 //=============================================================================
2022 // Generate a fast path/slow path idiom.  Graph looks like:
2023 // [foo] indicates that 'foo' is a parameter
2024 //
2025 //              [in]     NULL
2026 //                 \    /
2027 //                  CmpP
2028 //                  Bool ne
2029 //                   If
2030 //                  /  \
2031 //              True    False-<2>
2032 //              / |
2033 //             /  cast_not_null
2034 //           Load  |    |   ^
2035 //        [fast_test]   |   |
2036 // gvn to   opt_test    |   |
2037 //          /    \      |  <1>
2038 //      True     False  |
2039 //        |         \\  |
2040 //   [slow_call]     \[fast_result]
2041 //    Ctl   Val       \      \
2042 //     |               \      \
2043 //    Catch       <1>   \      \
2044 //   /    \        ^     \      \
2045 //  Ex    No_Ex    |      \      \
2046 //  |       \   \  |       \ <2>  \
2047 //  ...      \  [slow_res] |  |    \   [null_result]
2048 //            \         \--+--+---  |  |
2049 //             \           | /    \ | /
2050 //              --------Region     Phi
2051 //
2052 //=============================================================================
2053 // Code is structured as a series of driver functions all called 'do_XXX' that
2054 // call a set of helper functions.  Helper functions first, then drivers.
2055 
2056 //------------------------------null_check_oop---------------------------------
2057 // Null check oop.  Set null-path control into Region in slot 3.
2058 // Make a cast-not-nullness use the other not-null control.  Return cast.
2059 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2060                                bool never_see_null) {
2061   // Initial NULL check taken path
2062   (*null_control) = top();
2063   Node* cast = null_check_common(value, T_OBJECT, false, null_control);
2064 
2065   // Generate uncommon_trap:
2066   if (never_see_null && (*null_control) != top()) {
2067     // If we see an unexpected null at a check-cast we record it and force a
2068     // recompile; the offending check-cast will be compiled to handle NULLs.
2069     // If we see more than one offending BCI, then all checkcasts in the
2070     // method will be compiled to handle NULLs.
2071     PreserveJVMState pjvms(this);
2072     set_control(*null_control);
2073     replace_in_map(value, null());
2074     uncommon_trap(Deoptimization::Reason_null_check,
2075                   Deoptimization::Action_make_not_entrant);
2076     (*null_control) = top();    // NULL path is dead
2077   }
2078 
2079   // Cast away null-ness on the result
2080   return cast;
2081 }
2082 
2083 //------------------------------opt_iff----------------------------------------
2084 // Optimize the fast-check IfNode.  Set the fast-path region slot 2.
2085 // Return slow-path control.
2086 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2087   IfNode *opt_iff = _gvn.transform(iff)->as_If();
2088 
2089   // Fast path taken; set region slot 2
2090   Node *fast_taken = _gvn.transform( new (C, 1) IfFalseNode(opt_iff) );
2091   region->init_req(2,fast_taken); // Capture fast-control
2092 
2093   // Fast path not-taken, i.e. slow path
2094   Node *slow_taken = _gvn.transform( new (C, 1) IfTrueNode(opt_iff) );
2095   return slow_taken;
2096 }
2097 
2098 //-----------------------------make_runtime_call-------------------------------
2099 Node* GraphKit::make_runtime_call(int flags,
2100                                   const TypeFunc* call_type, address call_addr,
2101                                   const char* call_name,
2102                                   const TypePtr* adr_type,
2103                                   // The following parms are all optional.
2104                                   // The first NULL ends the list.
2105                                   Node* parm0, Node* parm1,
2106                                   Node* parm2, Node* parm3,
2107                                   Node* parm4, Node* parm5,
2108                                   Node* parm6, Node* parm7) {
2109   // Slow-path call
2110   int size = call_type->domain()->cnt();
2111   bool is_leaf = !(flags & RC_NO_LEAF);
2112   bool has_io  = (!is_leaf && !(flags & RC_NO_IO));
2113   if (call_name == NULL) {
2114     assert(!is_leaf, "must supply name for leaf");
2115     call_name = OptoRuntime::stub_name(call_addr);
2116   }
2117   CallNode* call;
2118   if (!is_leaf) {
2119     call = new(C, size) CallStaticJavaNode(call_type, call_addr, call_name,
2120                                            bci(), adr_type);
2121   } else if (flags & RC_NO_FP) {
2122     call = new(C, size) CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2123   } else {
2124     call = new(C, size) CallLeafNode(call_type, call_addr, call_name, adr_type);
2125   }
2126 
2127   // The following is similar to set_edges_for_java_call,
2128   // except that the memory effects of the call are restricted to AliasIdxRaw.
2129 
2130   // Slow path call has no side-effects, uses few values
2131   bool wide_in  = !(flags & RC_NARROW_MEM);
2132   bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2133 
2134   Node* prev_mem = NULL;
2135   if (wide_in) {
2136     prev_mem = set_predefined_input_for_runtime_call(call);
2137   } else {
2138     assert(!wide_out, "narrow in => narrow out");
2139     Node* narrow_mem = memory(adr_type);
2140     prev_mem = reset_memory();
2141     map()->set_memory(narrow_mem);
2142     set_predefined_input_for_runtime_call(call);
2143   }
2144 
2145   // Hook each parm in order.  Stop looking at the first NULL.
2146   if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0);
2147   if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1);
2148   if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2);
2149   if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3);
2150   if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4);
2151   if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5);
2152   if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6);
2153   if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7);
2154     /* close each nested if ===> */  } } } } } } } }
2155   assert(call->in(call->req()-1) != NULL, "must initialize all parms");
2156 
2157   if (!is_leaf) {
2158     // Non-leaves can block and take safepoints:
2159     add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2160   }
2161   // Non-leaves can throw exceptions:
2162   if (has_io) {
2163     call->set_req(TypeFunc::I_O, i_o());
2164   }
2165 
2166   if (flags & RC_UNCOMMON) {
2167     // Set the count to a tiny probability.  Cf. Estimate_Block_Frequency.
2168     // (An "if" probability corresponds roughly to an unconditional count.
2169     // Sort of.)
2170     call->set_cnt(PROB_UNLIKELY_MAG(4));
2171   }
2172 
2173   Node* c = _gvn.transform(call);
2174   assert(c == call, "cannot disappear");
2175 
2176   if (wide_out) {
2177     // Slow path call has full side-effects.
2178     set_predefined_output_for_runtime_call(call);
2179   } else {
2180     // Slow path call has few side-effects, and/or sets few values.
2181     set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2182   }
2183 
2184   if (has_io) {
2185     set_i_o(_gvn.transform(new (C, 1) ProjNode(call, TypeFunc::I_O)));
2186   }
2187   return call;
2188 
2189 }
2190 
2191 //------------------------------merge_memory-----------------------------------
2192 // Merge memory from one path into the current memory state.
2193 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2194   for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2195     Node* old_slice = mms.force_memory();
2196     Node* new_slice = mms.memory2();
2197     if (old_slice != new_slice) {
2198       PhiNode* phi;
2199       if (new_slice->is_Phi() && new_slice->as_Phi()->region() == region) {
2200         phi = new_slice->as_Phi();
2201         #ifdef ASSERT
2202         if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region)
2203           old_slice = old_slice->in(new_path);
2204         // Caller is responsible for ensuring that any pre-existing
2205         // phis are already aware of old memory.
2206         int old_path = (new_path > 1) ? 1 : 2;  // choose old_path != new_path
2207         assert(phi->in(old_path) == old_slice, "pre-existing phis OK");
2208         #endif
2209         mms.set_memory(phi);
2210       } else {
2211         phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2212         _gvn.set_type(phi, Type::MEMORY);
2213         phi->set_req(new_path, new_slice);
2214         mms.set_memory(_gvn.transform(phi));  // assume it is complete
2215       }
2216     }
2217   }
2218 }
2219 
2220 //------------------------------make_slow_call_ex------------------------------
2221 // Make the exception handler hookups for the slow call
2222 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj) {
2223   if (stopped())  return;
2224 
2225   // Make a catch node with just two handlers:  fall-through and catch-all
2226   Node* i_o  = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2227   Node* catc = _gvn.transform( new (C, 2) CatchNode(control(), i_o, 2) );
2228   Node* norm = _gvn.transform( new (C, 1) CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) );
2229   Node* excp = _gvn.transform( new (C, 1) CatchProjNode(catc, CatchProjNode::catch_all_index,    CatchProjNode::no_handler_bci) );
2230 
2231   { PreserveJVMState pjvms(this);
2232     set_control(excp);
2233     set_i_o(i_o);
2234 
2235     if (excp != top()) {
2236       // Create an exception state also.
2237       // Use an exact type if the caller has specified a specific exception.
2238       const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2239       Node*       ex_oop  = new (C, 2) CreateExNode(ex_type, control(), i_o);
2240       add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2241     }
2242   }
2243 
2244   // Get the no-exception control from the CatchNode.
2245   set_control(norm);
2246 }
2247 
2248 
2249 //-------------------------------gen_subtype_check-----------------------------
2250 // Generate a subtyping check.  Takes as input the subtype and supertype.
2251 // Returns 2 values: sets the default control() to the true path and returns
2252 // the false path.  Only reads invariant memory; sets no (visible) memory.
2253 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2254 // but that's not exposed to the optimizer.  This call also doesn't take in an
2255 // Object; if you wish to check an Object you need to load the Object's class
2256 // prior to coming here.
2257 Node* GraphKit::gen_subtype_check(Node* subklass, Node* superklass) {
2258   // Fast check for identical types, perhaps identical constants.
2259   // The types can even be identical non-constants, in cases
2260   // involving Array.newInstance, Object.clone, etc.
2261   if (subklass == superklass)
2262     return top();             // false path is dead; no test needed.
2263 
2264   if (_gvn.type(superklass)->singleton()) {
2265     ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2266     ciKlass* subk   = _gvn.type(subklass)->is_klassptr()->klass();
2267 
2268     // In the common case of an exact superklass, try to fold up the
2269     // test before generating code.  You may ask, why not just generate
2270     // the code and then let it fold up?  The answer is that the generated
2271     // code will necessarily include null checks, which do not always
2272     // completely fold away.  If they are also needless, then they turn
2273     // into a performance loss.  Example:
2274     //    Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2275     // Here, the type of 'fa' is often exact, so the store check
2276     // of fa[1]=x will fold up, without testing the nullness of x.
2277     switch (static_subtype_check(superk, subk)) {
2278     case SSC_always_false:
2279       {
2280         Node* always_fail = control();
2281         set_control(top());
2282         return always_fail;
2283       }
2284     case SSC_always_true:
2285       return top();
2286     case SSC_easy_test:
2287       {
2288         // Just do a direct pointer compare and be done.
2289         Node* cmp = _gvn.transform( new(C, 3) CmpPNode(subklass, superklass) );
2290         Node* bol = _gvn.transform( new(C, 2) BoolNode(cmp, BoolTest::eq) );
2291         IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN);
2292         set_control( _gvn.transform( new(C, 1) IfTrueNode (iff) ) );
2293         return       _gvn.transform( new(C, 1) IfFalseNode(iff) );
2294       }
2295     case SSC_full_test:
2296       break;
2297     default:
2298       ShouldNotReachHere();
2299     }
2300   }
2301 
2302   // %%% Possible further optimization:  Even if the superklass is not exact,
2303   // if the subklass is the unique subtype of the superklass, the check
2304   // will always succeed.  We could leave a dependency behind to ensure this.
2305 
2306   // First load the super-klass's check-offset
2307   Node *p1 = basic_plus_adr( superklass, superklass, in_bytes(Klass::super_check_offset_offset()) );
2308   Node *chk_off = _gvn.transform( new (C, 3) LoadINode( NULL, memory(p1), p1, _gvn.type(p1)->is_ptr() ) );
2309   int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2310   bool might_be_cache = (find_int_con(chk_off, cacheoff_con) == cacheoff_con);
2311 
2312   // Load from the sub-klass's super-class display list, or a 1-word cache of
2313   // the secondary superclass list, or a failing value with a sentinel offset
2314   // if the super-klass is an interface or exceptionally deep in the Java
2315   // hierarchy and we have to scan the secondary superclass list the hard way.
2316   // Worst-case type is a little odd: NULL is allowed as a result (usually
2317   // klass loads can never produce a NULL).
2318   Node *chk_off_X = ConvI2X(chk_off);
2319   Node *p2 = _gvn.transform( new (C, 4) AddPNode(subklass,subklass,chk_off_X) );
2320   // For some types like interfaces the following loadKlass is from a 1-word
2321   // cache which is mutable so can't use immutable memory.  Other
2322   // types load from the super-class display table which is immutable.
2323   Node *kmem = might_be_cache ? memory(p2) : immutable_memory();
2324   Node *nkls = _gvn.transform( LoadKlassNode::make( _gvn, kmem, p2, _gvn.type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL ) );
2325 
2326   // Compile speed common case: ARE a subtype and we canNOT fail
2327   if( superklass == nkls )
2328     return top();             // false path is dead; no test needed.
2329 
2330   // See if we get an immediate positive hit.  Happens roughly 83% of the
2331   // time.  Test to see if the value loaded just previously from the subklass
2332   // is exactly the superklass.
2333   Node *cmp1 = _gvn.transform( new (C, 3) CmpPNode( superklass, nkls ) );
2334   Node *bol1 = _gvn.transform( new (C, 2) BoolNode( cmp1, BoolTest::eq ) );
2335   IfNode *iff1 = create_and_xform_if( control(), bol1, PROB_LIKELY(0.83f), COUNT_UNKNOWN );
2336   Node *iftrue1 = _gvn.transform( new (C, 1) IfTrueNode ( iff1 ) );
2337   set_control(    _gvn.transform( new (C, 1) IfFalseNode( iff1 ) ) );
2338 
2339   // Compile speed common case: Check for being deterministic right now.  If
2340   // chk_off is a constant and not equal to cacheoff then we are NOT a
2341   // subklass.  In this case we need exactly the 1 test above and we can
2342   // return those results immediately.
2343   if (!might_be_cache) {
2344     Node* not_subtype_ctrl = control();
2345     set_control(iftrue1); // We need exactly the 1 test above
2346     return not_subtype_ctrl;
2347   }
2348 
2349   // Gather the various success & failures here
2350   RegionNode *r_ok_subtype = new (C, 4) RegionNode(4);
2351   record_for_igvn(r_ok_subtype);
2352   RegionNode *r_not_subtype = new (C, 3) RegionNode(3);
2353   record_for_igvn(r_not_subtype);
2354 
2355   r_ok_subtype->init_req(1, iftrue1);
2356 
2357   // Check for immediate negative hit.  Happens roughly 11% of the time (which
2358   // is roughly 63% of the remaining cases).  Test to see if the loaded
2359   // check-offset points into the subklass display list or the 1-element
2360   // cache.  If it points to the display (and NOT the cache) and the display
2361   // missed then it's not a subtype.
2362   Node *cacheoff = _gvn.intcon(cacheoff_con);
2363   Node *cmp2 = _gvn.transform( new (C, 3) CmpINode( chk_off, cacheoff ) );
2364   Node *bol2 = _gvn.transform( new (C, 2) BoolNode( cmp2, BoolTest::ne ) );
2365   IfNode *iff2 = create_and_xform_if( control(), bol2, PROB_LIKELY(0.63f), COUNT_UNKNOWN );
2366   r_not_subtype->init_req(1, _gvn.transform( new (C, 1) IfTrueNode (iff2) ) );
2367   set_control(                _gvn.transform( new (C, 1) IfFalseNode(iff2) ) );
2368 
2369   // Check for self.  Very rare to get here, but it is taken 1/3 the time.
2370   // No performance impact (too rare) but allows sharing of secondary arrays
2371   // which has some footprint reduction.
2372   Node *cmp3 = _gvn.transform( new (C, 3) CmpPNode( subklass, superklass ) );
2373   Node *bol3 = _gvn.transform( new (C, 2) BoolNode( cmp3, BoolTest::eq ) );
2374   IfNode *iff3 = create_and_xform_if( control(), bol3, PROB_LIKELY(0.36f), COUNT_UNKNOWN );
2375   r_ok_subtype->init_req(2, _gvn.transform( new (C, 1) IfTrueNode ( iff3 ) ) );
2376   set_control(               _gvn.transform( new (C, 1) IfFalseNode( iff3 ) ) );
2377 
2378   // -- Roads not taken here: --
2379   // We could also have chosen to perform the self-check at the beginning
2380   // of this code sequence, as the assembler does.  This would not pay off
2381   // the same way, since the optimizer, unlike the assembler, can perform
2382   // static type analysis to fold away many successful self-checks.
2383   // Non-foldable self checks work better here in second position, because
2384   // the initial primary superclass check subsumes a self-check for most
2385   // types.  An exception would be a secondary type like array-of-interface,
2386   // which does not appear in its own primary supertype display.
2387   // Finally, we could have chosen to move the self-check into the
2388   // PartialSubtypeCheckNode, and from there out-of-line in a platform
2389   // dependent manner.  But it is worthwhile to have the check here,
2390   // where it can be perhaps be optimized.  The cost in code space is
2391   // small (register compare, branch).
2392 
2393   // Now do a linear scan of the secondary super-klass array.  Again, no real
2394   // performance impact (too rare) but it's gotta be done.
2395   // Since the code is rarely used, there is no penalty for moving it
2396   // out of line, and it can only improve I-cache density.
2397   // The decision to inline or out-of-line this final check is platform
2398   // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2399   Node* psc = _gvn.transform(
2400     new (C, 3) PartialSubtypeCheckNode(control(), subklass, superklass) );
2401 
2402   Node *cmp4 = _gvn.transform( new (C, 3) CmpPNode( psc, null() ) );
2403   Node *bol4 = _gvn.transform( new (C, 2) BoolNode( cmp4, BoolTest::ne ) );
2404   IfNode *iff4 = create_and_xform_if( control(), bol4, PROB_FAIR, COUNT_UNKNOWN );
2405   r_not_subtype->init_req(2, _gvn.transform( new (C, 1) IfTrueNode (iff4) ) );
2406   r_ok_subtype ->init_req(3, _gvn.transform( new (C, 1) IfFalseNode(iff4) ) );
2407 
2408   // Return false path; set default control to true path.
2409   set_control( _gvn.transform(r_ok_subtype) );
2410   return _gvn.transform(r_not_subtype);
2411 }
2412 
2413 //----------------------------static_subtype_check-----------------------------
2414 // Shortcut important common cases when superklass is exact:
2415 // (0) superklass is java.lang.Object (can occur in reflective code)
2416 // (1) subklass is already limited to a subtype of superklass => always ok
2417 // (2) subklass does not overlap with superklass => always fail
2418 // (3) superklass has NO subtypes and we can check with a simple compare.
2419 int GraphKit::static_subtype_check(ciKlass* superk, ciKlass* subk) {
2420   if (StressReflectiveCode) {
2421     return SSC_full_test;       // Let caller generate the general case.
2422   }
2423 
2424   if (superk == env()->Object_klass()) {
2425     return SSC_always_true;     // (0) this test cannot fail
2426   }
2427 
2428   ciType* superelem = superk;
2429   if (superelem->is_array_klass())
2430     superelem = superelem->as_array_klass()->base_element_type();
2431 
2432   if (!subk->is_interface()) {  // cannot trust static interface types yet
2433     if (subk->is_subtype_of(superk)) {
2434       return SSC_always_true;   // (1) false path dead; no dynamic test needed
2435     }
2436     if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
2437         !superk->is_subtype_of(subk)) {
2438       return SSC_always_false;
2439     }
2440   }
2441 
2442   // If casting to an instance klass, it must have no subtypes
2443   if (superk->is_interface()) {
2444     // Cannot trust interfaces yet.
2445     // %%% S.B. superk->nof_implementors() == 1
2446   } else if (superelem->is_instance_klass()) {
2447     ciInstanceKlass* ik = superelem->as_instance_klass();
2448     if (!ik->has_subklass() && !ik->is_interface()) {
2449       if (!ik->is_final()) {
2450         // Add a dependency if there is a chance of a later subclass.
2451         C->dependencies()->assert_leaf_type(ik);
2452       }
2453       return SSC_easy_test;     // (3) caller can do a simple ptr comparison
2454     }
2455   } else {
2456     // A primitive array type has no subtypes.
2457     return SSC_easy_test;       // (3) caller can do a simple ptr comparison
2458   }
2459 
2460   return SSC_full_test;
2461 }
2462 
2463 // Profile-driven exact type check:
2464 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2465                                     float prob,
2466                                     Node* *casted_receiver) {
2467   const TypeKlassPtr* tklass = TypeKlassPtr::make(klass);
2468   Node* recv_klass = load_object_klass(receiver);
2469   Node* want_klass = makecon(tklass);
2470   Node* cmp = _gvn.transform( new(C, 3) CmpPNode(recv_klass, want_klass) );
2471   Node* bol = _gvn.transform( new(C, 2) BoolNode(cmp, BoolTest::eq) );
2472   IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2473   set_control( _gvn.transform( new(C, 1) IfTrueNode (iff) ));
2474   Node* fail = _gvn.transform( new(C, 1) IfFalseNode(iff) );
2475 
2476   const TypeOopPtr* recv_xtype = tklass->as_instance_type();
2477   assert(recv_xtype->klass_is_exact(), "");
2478 
2479   // Subsume downstream occurrences of receiver with a cast to
2480   // recv_xtype, since now we know what the type will be.
2481   Node* cast = new(C, 2) CheckCastPPNode(control(), receiver, recv_xtype);
2482   (*casted_receiver) = _gvn.transform(cast);
2483   // (User must make the replace_in_map call.)
2484 
2485   return fail;
2486 }
2487 
2488 
2489 //------------------------------seems_never_null-------------------------------
2490 // Use null_seen information if it is available from the profile.
2491 // If we see an unexpected null at a type check we record it and force a
2492 // recompile; the offending check will be recompiled to handle NULLs.
2493 // If we see several offending BCIs, then all checks in the
2494 // method will be recompiled.
2495 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data) {
2496   if (UncommonNullCast               // Cutout for this technique
2497       && obj != null()               // And not the -Xcomp stupid case?
2498       && !too_many_traps(Deoptimization::Reason_null_check)
2499       ) {
2500     if (data == NULL)
2501       // Edge case:  no mature data.  Be optimistic here.
2502       return true;
2503     // If the profile has not seen a null, assume it won't happen.
2504     assert(java_bc() == Bytecodes::_checkcast ||
2505            java_bc() == Bytecodes::_instanceof ||
2506            java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
2507     return !data->as_BitData()->null_seen();
2508   }
2509   return false;
2510 }
2511 
2512 //------------------------maybe_cast_profiled_receiver-------------------------
2513 // If the profile has seen exactly one type, narrow to exactly that type.
2514 // Subsequent type checks will always fold up.
2515 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
2516                                              ciProfileData* data,
2517                                              ciKlass* require_klass) {
2518   if (!UseTypeProfile || !TypeProfileCasts) return NULL;
2519   if (data == NULL)  return NULL;
2520 
2521   // Make sure we haven't already deoptimized from this tactic.
2522   if (too_many_traps(Deoptimization::Reason_class_check))
2523     return NULL;
2524 
2525   // (No, this isn't a call, but it's enough like a virtual call
2526   // to use the same ciMethod accessor to get the profile info...)
2527   ciCallProfile profile = method()->call_profile_at_bci(bci());
2528   if (profile.count() >= 0 &&         // no cast failures here
2529       profile.has_receiver(0) &&
2530       profile.morphism() == 1) {
2531     ciKlass* exact_kls = profile.receiver(0);
2532     if (require_klass == NULL ||
2533         static_subtype_check(require_klass, exact_kls) == SSC_always_true) {
2534       // If we narrow the type to match what the type profile sees,
2535       // we can then remove the rest of the cast.
2536       // This is a win, even if the exact_kls is very specific,
2537       // because downstream operations, such as method calls,
2538       // will often benefit from the sharper type.
2539       Node* exact_obj = not_null_obj; // will get updated in place...
2540       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
2541                                             &exact_obj);
2542       { PreserveJVMState pjvms(this);
2543         set_control(slow_ctl);
2544         uncommon_trap(Deoptimization::Reason_class_check,
2545                       Deoptimization::Action_maybe_recompile);
2546       }
2547       replace_in_map(not_null_obj, exact_obj);
2548       return exact_obj;
2549     }
2550     // assert(ssc == SSC_always_true)... except maybe the profile lied to us.
2551   }
2552 
2553   return NULL;
2554 }
2555 
2556 
2557 //-------------------------------gen_instanceof--------------------------------
2558 // Generate an instance-of idiom.  Used by both the instance-of bytecode
2559 // and the reflective instance-of call.
2560 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass) {
2561   kill_dead_locals();           // Benefit all the uncommon traps
2562   assert( !stopped(), "dead parse path should be checked in callers" );
2563   assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
2564          "must check for not-null not-dead klass in callers");
2565 
2566   // Make the merge point
2567   enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
2568   RegionNode* region = new(C, PATH_LIMIT) RegionNode(PATH_LIMIT);
2569   Node*       phi    = new(C, PATH_LIMIT) PhiNode(region, TypeInt::BOOL);
2570   C->set_has_split_ifs(true); // Has chance for split-if optimization
2571 
2572   ciProfileData* data = NULL;
2573   if (java_bc() == Bytecodes::_instanceof) {  // Only for the bytecode
2574     data = method()->method_data()->bci_to_data(bci());
2575   }
2576   bool never_see_null = (ProfileDynamicTypes  // aggressive use of profile
2577                          && seems_never_null(obj, data));
2578 
2579   // Null check; get casted pointer; set region slot 3
2580   Node* null_ctl = top();
2581   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null);
2582 
2583   // If not_null_obj is dead, only null-path is taken
2584   if (stopped()) {              // Doing instance-of on a NULL?
2585     set_control(null_ctl);
2586     return intcon(0);
2587   }
2588   region->init_req(_null_path, null_ctl);
2589   phi   ->init_req(_null_path, intcon(0)); // Set null path value
2590   if (null_ctl == top()) {
2591     // Do this eagerly, so that pattern matches like is_diamond_phi
2592     // will work even during parsing.
2593     assert(_null_path == PATH_LIMIT-1, "delete last");
2594     region->del_req(_null_path);
2595     phi   ->del_req(_null_path);
2596   }
2597 
2598   if (ProfileDynamicTypes && data != NULL) {
2599     Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, data, NULL);
2600     if (stopped()) {            // Profile disagrees with this path.
2601       set_control(null_ctl);    // Null is the only remaining possibility.
2602       return intcon(0);
2603     }
2604     if (cast_obj != NULL)
2605       not_null_obj = cast_obj;
2606   }
2607 
2608   // Load the object's klass
2609   Node* obj_klass = load_object_klass(not_null_obj);
2610 
2611   // Generate the subtype check
2612   Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass);
2613 
2614   // Plug in the success path to the general merge in slot 1.
2615   region->init_req(_obj_path, control());
2616   phi   ->init_req(_obj_path, intcon(1));
2617 
2618   // Plug in the failing path to the general merge in slot 2.
2619   region->init_req(_fail_path, not_subtype_ctrl);
2620   phi   ->init_req(_fail_path, intcon(0));
2621 
2622   // Return final merged results
2623   set_control( _gvn.transform(region) );
2624   record_for_igvn(region);
2625   return _gvn.transform(phi);
2626 }
2627 
2628 //-------------------------------gen_checkcast---------------------------------
2629 // Generate a checkcast idiom.  Used by both the checkcast bytecode and the
2630 // array store bytecode.  Stack must be as-if BEFORE doing the bytecode so the
2631 // uncommon-trap paths work.  Adjust stack after this call.
2632 // If failure_control is supplied and not null, it is filled in with
2633 // the control edge for the cast failure.  Otherwise, an appropriate
2634 // uncommon trap or exception is thrown.
2635 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
2636                               Node* *failure_control) {
2637   kill_dead_locals();           // Benefit all the uncommon traps
2638   const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr();
2639   const Type *toop = TypeOopPtr::make_from_klass(tk->klass());
2640 
2641   // Fast cutout:  Check the case that the cast is vacuously true.
2642   // This detects the common cases where the test will short-circuit
2643   // away completely.  We do this before we perform the null check,
2644   // because if the test is going to turn into zero code, we don't
2645   // want a residual null check left around.  (Causes a slowdown,
2646   // for example, in some objArray manipulations, such as a[i]=a[j].)
2647   if (tk->singleton()) {
2648     const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
2649     if (objtp != NULL && objtp->klass() != NULL) {
2650       switch (static_subtype_check(tk->klass(), objtp->klass())) {
2651       case SSC_always_true:
2652         return obj;
2653       case SSC_always_false:
2654         // It needs a null check because a null will *pass* the cast check.
2655         // A non-null value will always produce an exception.
2656         return do_null_assert(obj, T_OBJECT);
2657       }
2658     }
2659   }
2660 
2661   ciProfileData* data = NULL;
2662   if (failure_control == NULL) {        // use MDO in regular case only
2663     assert(java_bc() == Bytecodes::_aastore ||
2664            java_bc() == Bytecodes::_checkcast,
2665            "interpreter profiles type checks only for these BCs");
2666     data = method()->method_data()->bci_to_data(bci());
2667   }
2668 
2669   // Make the merge point
2670   enum { _obj_path = 1, _null_path, PATH_LIMIT };
2671   RegionNode* region = new (C, PATH_LIMIT) RegionNode(PATH_LIMIT);
2672   Node*       phi    = new (C, PATH_LIMIT) PhiNode(region, toop);
2673   C->set_has_split_ifs(true); // Has chance for split-if optimization
2674 
2675   // Use null-cast information if it is available
2676   bool never_see_null = ((failure_control == NULL)  // regular case only
2677                          && seems_never_null(obj, data));
2678 
2679   // Null check; get casted pointer; set region slot 3
2680   Node* null_ctl = top();
2681   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null);
2682 
2683   // If not_null_obj is dead, only null-path is taken
2684   if (stopped()) {              // Doing instance-of on a NULL?
2685     set_control(null_ctl);
2686     return null();
2687   }
2688   region->init_req(_null_path, null_ctl);
2689   phi   ->init_req(_null_path, null());  // Set null path value
2690   if (null_ctl == top()) {
2691     // Do this eagerly, so that pattern matches like is_diamond_phi
2692     // will work even during parsing.
2693     assert(_null_path == PATH_LIMIT-1, "delete last");
2694     region->del_req(_null_path);
2695     phi   ->del_req(_null_path);
2696   }
2697 
2698   Node* cast_obj = NULL;
2699   if (data != NULL &&
2700       // Counter has never been decremented (due to cast failure).
2701       // ...This is a reasonable thing to expect.  It is true of
2702       // all casts inserted by javac to implement generic types.
2703       data->as_CounterData()->count() >= 0) {
2704     cast_obj = maybe_cast_profiled_receiver(not_null_obj, data, tk->klass());
2705     if (cast_obj != NULL) {
2706       if (failure_control != NULL) // failure is now impossible
2707         (*failure_control) = top();
2708       // adjust the type of the phi to the exact klass:
2709       phi->raise_bottom_type(_gvn.type(cast_obj)->meet(TypePtr::NULL_PTR));
2710     }
2711   }
2712 
2713   if (cast_obj == NULL) {
2714     // Load the object's klass
2715     Node* obj_klass = load_object_klass(not_null_obj);
2716 
2717     // Generate the subtype check
2718     Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass );
2719 
2720     // Plug in success path into the merge
2721     cast_obj = _gvn.transform(new (C, 2) CheckCastPPNode(control(),
2722                                                          not_null_obj, toop));
2723     // Failure path ends in uncommon trap (or may be dead - failure impossible)
2724     if (failure_control == NULL) {
2725       if (not_subtype_ctrl != top()) { // If failure is possible
2726         PreserveJVMState pjvms(this);
2727         set_control(not_subtype_ctrl);
2728         builtin_throw(Deoptimization::Reason_class_check, obj_klass);
2729       }
2730     } else {
2731       (*failure_control) = not_subtype_ctrl;
2732     }
2733   }
2734 
2735   region->init_req(_obj_path, control());
2736   phi   ->init_req(_obj_path, cast_obj);
2737 
2738   // A merge of NULL or Casted-NotNull obj
2739   Node* res = _gvn.transform(phi);
2740 
2741   // Note I do NOT always 'replace_in_map(obj,result)' here.
2742   //  if( tk->klass()->can_be_primary_super()  )
2743     // This means that if I successfully store an Object into an array-of-String
2744     // I 'forget' that the Object is really now known to be a String.  I have to
2745     // do this because we don't have true union types for interfaces - if I store
2746     // a Baz into an array-of-Interface and then tell the optimizer it's an
2747     // Interface, I forget that it's also a Baz and cannot do Baz-like field
2748     // references to it.  FIX THIS WHEN UNION TYPES APPEAR!
2749   //  replace_in_map( obj, res );
2750 
2751   // Return final merged results
2752   set_control( _gvn.transform(region) );
2753   record_for_igvn(region);
2754   return res;
2755 }
2756 
2757 //------------------------------next_monitor-----------------------------------
2758 // What number should be given to the next monitor?
2759 int GraphKit::next_monitor() {
2760   int current = jvms()->monitor_depth()* C->sync_stack_slots();
2761   int next = current + C->sync_stack_slots();
2762   // Keep the toplevel high water mark current:
2763   if (C->fixed_slots() < next)  C->set_fixed_slots(next);
2764   return current;
2765 }
2766 
2767 //------------------------------insert_mem_bar---------------------------------
2768 // Memory barrier to avoid floating things around
2769 // The membar serves as a pinch point between both control and all memory slices.
2770 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
2771   MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
2772   mb->init_req(TypeFunc::Control, control());
2773   mb->init_req(TypeFunc::Memory,  reset_memory());
2774   Node* membar = _gvn.transform(mb);
2775   set_control(_gvn.transform(new (C, 1) ProjNode(membar,TypeFunc::Control) ));
2776   set_all_memory_call(membar);
2777   return membar;
2778 }
2779 
2780 //-------------------------insert_mem_bar_volatile----------------------------
2781 // Memory barrier to avoid floating things around
2782 // The membar serves as a pinch point between both control and memory(alias_idx).
2783 // If you want to make a pinch point on all memory slices, do not use this
2784 // function (even with AliasIdxBot); use insert_mem_bar() instead.
2785 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
2786   // When Parse::do_put_xxx updates a volatile field, it appends a series
2787   // of MemBarVolatile nodes, one for *each* volatile field alias category.
2788   // The first membar is on the same memory slice as the field store opcode.
2789   // This forces the membar to follow the store.  (Bug 6500685 broke this.)
2790   // All the other membars (for other volatile slices, including AliasIdxBot,
2791   // which stands for all unknown volatile slices) are control-dependent
2792   // on the first membar.  This prevents later volatile loads or stores
2793   // from sliding up past the just-emitted store.
2794 
2795   MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
2796   mb->set_req(TypeFunc::Control,control());
2797   if (alias_idx == Compile::AliasIdxBot) {
2798     mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
2799   } else {
2800     assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
2801     mb->set_req(TypeFunc::Memory, memory(alias_idx));
2802   }
2803   Node* membar = _gvn.transform(mb);
2804   set_control(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Control)));
2805   if (alias_idx == Compile::AliasIdxBot) {
2806     merged_memory()->set_base_memory(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Memory)));
2807   } else {
2808     set_memory(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Memory)),alias_idx);
2809   }
2810   return membar;
2811 }
2812 
2813 //------------------------------shared_lock------------------------------------
2814 // Emit locking code.
2815 FastLockNode* GraphKit::shared_lock(Node* obj) {
2816   // bci is either a monitorenter bc or InvocationEntryBci
2817   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
2818   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
2819 
2820   if( !GenerateSynchronizationCode )
2821     return NULL;                // Not locking things?
2822   if (stopped())                // Dead monitor?
2823     return NULL;
2824 
2825   assert(dead_locals_are_killed(), "should kill locals before sync. point");
2826 
2827   // Box the stack location
2828   Node* box = _gvn.transform(new (C, 1) BoxLockNode(next_monitor()));
2829   Node* mem = reset_memory();
2830 
2831   FastLockNode * flock = _gvn.transform(new (C, 3) FastLockNode(0, obj, box) )->as_FastLock();
2832   if (PrintPreciseBiasedLockingStatistics) {
2833     // Create the counters for this fast lock.
2834     flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci
2835   }
2836   // Add monitor to debug info for the slow path.  If we block inside the
2837   // slow path and de-opt, we need the monitor hanging around
2838   map()->push_monitor( flock );
2839 
2840   const TypeFunc *tf = LockNode::lock_type();
2841   LockNode *lock = new (C, tf->domain()->cnt()) LockNode(C, tf);
2842 
2843   lock->init_req( TypeFunc::Control, control() );
2844   lock->init_req( TypeFunc::Memory , mem );
2845   lock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
2846   lock->init_req( TypeFunc::FramePtr, frameptr() );
2847   lock->init_req( TypeFunc::ReturnAdr, top() );
2848 
2849   lock->init_req(TypeFunc::Parms + 0, obj);
2850   lock->init_req(TypeFunc::Parms + 1, box);
2851   lock->init_req(TypeFunc::Parms + 2, flock);
2852   add_safepoint_edges(lock);
2853 
2854   lock = _gvn.transform( lock )->as_Lock();
2855 
2856   // lock has no side-effects, sets few values
2857   set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
2858 
2859   insert_mem_bar(Op_MemBarAcquireLock);
2860 
2861   // Add this to the worklist so that the lock can be eliminated
2862   record_for_igvn(lock);
2863 
2864 #ifndef PRODUCT
2865   if (PrintLockStatistics) {
2866     // Update the counter for this lock.  Don't bother using an atomic
2867     // operation since we don't require absolute accuracy.
2868     lock->create_lock_counter(map()->jvms());
2869     increment_counter(lock->counter()->addr());
2870   }
2871 #endif
2872 
2873   return flock;
2874 }
2875 
2876 
2877 //------------------------------shared_unlock----------------------------------
2878 // Emit unlocking code.
2879 void GraphKit::shared_unlock(Node* box, Node* obj) {
2880   // bci is either a monitorenter bc or InvocationEntryBci
2881   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
2882   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
2883 
2884   if( !GenerateSynchronizationCode )
2885     return;
2886   if (stopped()) {               // Dead monitor?
2887     map()->pop_monitor();        // Kill monitor from debug info
2888     return;
2889   }
2890 
2891   // Memory barrier to avoid floating things down past the locked region
2892   insert_mem_bar(Op_MemBarReleaseLock);
2893 
2894   const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
2895   UnlockNode *unlock = new (C, tf->domain()->cnt()) UnlockNode(C, tf);
2896   uint raw_idx = Compile::AliasIdxRaw;
2897   unlock->init_req( TypeFunc::Control, control() );
2898   unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
2899   unlock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
2900   unlock->init_req( TypeFunc::FramePtr, frameptr() );
2901   unlock->init_req( TypeFunc::ReturnAdr, top() );
2902 
2903   unlock->init_req(TypeFunc::Parms + 0, obj);
2904   unlock->init_req(TypeFunc::Parms + 1, box);
2905   unlock = _gvn.transform(unlock)->as_Unlock();
2906 
2907   Node* mem = reset_memory();
2908 
2909   // unlock has no side-effects, sets few values
2910   set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
2911 
2912   // Kill monitor from debug info
2913   map()->pop_monitor( );
2914 }
2915 
2916 //-------------------------------get_layout_helper-----------------------------
2917 // If the given klass is a constant or known to be an array,
2918 // fetch the constant layout helper value into constant_value
2919 // and return (Node*)NULL.  Otherwise, load the non-constant
2920 // layout helper value, and return the node which represents it.
2921 // This two-faced routine is useful because allocation sites
2922 // almost always feature constant types.
2923 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
2924   const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr();
2925   if (!StressReflectiveCode && inst_klass != NULL) {
2926     ciKlass* klass = inst_klass->klass();
2927     bool    xklass = inst_klass->klass_is_exact();
2928     if (xklass || klass->is_array_klass()) {
2929       jint lhelper = klass->layout_helper();
2930       if (lhelper != Klass::_lh_neutral_value) {
2931         constant_value = lhelper;
2932         return (Node*) NULL;
2933       }
2934     }
2935   }
2936   constant_value = Klass::_lh_neutral_value;  // put in a known value
2937   Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
2938   return make_load(NULL, lhp, TypeInt::INT, T_INT);
2939 }
2940 
2941 // We just put in an allocate/initialize with a big raw-memory effect.
2942 // Hook selected additional alias categories on the initialization.
2943 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
2944                                 MergeMemNode* init_in_merge,
2945                                 Node* init_out_raw) {
2946   DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
2947   assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
2948 
2949   Node* prevmem = kit.memory(alias_idx);
2950   init_in_merge->set_memory_at(alias_idx, prevmem);
2951   kit.set_memory(init_out_raw, alias_idx);
2952 }
2953 
2954 //---------------------------set_output_for_allocation-------------------------
2955 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
2956                                           const TypeOopPtr* oop_type) {
2957   int rawidx = Compile::AliasIdxRaw;
2958   alloc->set_req( TypeFunc::FramePtr, frameptr() );
2959   add_safepoint_edges(alloc);
2960   Node* allocx = _gvn.transform(alloc);
2961   set_control( _gvn.transform(new (C, 1) ProjNode(allocx, TypeFunc::Control) ) );
2962   // create memory projection for i_o
2963   set_memory ( _gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
2964   make_slow_call_ex(allocx, env()->OutOfMemoryError_klass(), true);
2965 
2966   // create a memory projection as for the normal control path
2967   Node* malloc = _gvn.transform(new (C, 1) ProjNode(allocx, TypeFunc::Memory));
2968   set_memory(malloc, rawidx);
2969 
2970   // a normal slow-call doesn't change i_o, but an allocation does
2971   // we create a separate i_o projection for the normal control path
2972   set_i_o(_gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::I_O, false) ) );
2973   Node* rawoop = _gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::Parms) );
2974 
2975   // put in an initialization barrier
2976   InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
2977                                                  rawoop)->as_Initialize();
2978   assert(alloc->initialization() == init,  "2-way macro link must work");
2979   assert(init ->allocation()     == alloc, "2-way macro link must work");
2980   {
2981     // Extract memory strands which may participate in the new object's
2982     // initialization, and source them from the new InitializeNode.
2983     // This will allow us to observe initializations when they occur,
2984     // and link them properly (as a group) to the InitializeNode.
2985     assert(init->in(InitializeNode::Memory) == malloc, "");
2986     MergeMemNode* minit_in = MergeMemNode::make(C, malloc);
2987     init->set_req(InitializeNode::Memory, minit_in);
2988     record_for_igvn(minit_in); // fold it up later, if possible
2989     Node* minit_out = memory(rawidx);
2990     assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
2991     if (oop_type->isa_aryptr()) {
2992       const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
2993       int            elemidx  = C->get_alias_index(telemref);
2994       hook_memory_on_init(*this, elemidx, minit_in, minit_out);
2995     } else if (oop_type->isa_instptr()) {
2996       ciInstanceKlass* ik = oop_type->klass()->as_instance_klass();
2997       for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
2998         ciField* field = ik->nonstatic_field_at(i);
2999         if (field->offset() >= TrackedInitializationLimit * HeapWordSize)
3000           continue;  // do not bother to track really large numbers of fields
3001         // Find (or create) the alias category for this field:
3002         int fieldidx = C->alias_type(field)->index();
3003         hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3004       }
3005     }
3006   }
3007 
3008   // Cast raw oop to the real thing...
3009   Node* javaoop = new (C, 2) CheckCastPPNode(control(), rawoop, oop_type);
3010   javaoop = _gvn.transform(javaoop);
3011   C->set_recent_alloc(control(), javaoop);
3012   assert(just_allocated_object(control()) == javaoop, "just allocated");
3013 
3014 #ifdef ASSERT
3015   { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3016     assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc,
3017            "Ideal_allocation works");
3018     assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc,
3019            "Ideal_allocation works");
3020     if (alloc->is_AllocateArray()) {
3021       assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(),
3022              "Ideal_allocation works");
3023       assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(),
3024              "Ideal_allocation works");
3025     } else {
3026       assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3027     }
3028   }
3029 #endif //ASSERT
3030 
3031   return javaoop;
3032 }
3033 
3034 //---------------------------new_instance--------------------------------------
3035 // This routine takes a klass_node which may be constant (for a static type)
3036 // or may be non-constant (for reflective code).  It will work equally well
3037 // for either, and the graph will fold nicely if the optimizer later reduces
3038 // the type to a constant.
3039 // The optional arguments are for specialized use by intrinsics:
3040 //  - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3041 //  - If 'return_size_val', report the the total object size to the caller.
3042 Node* GraphKit::new_instance(Node* klass_node,
3043                              Node* extra_slow_test,
3044                              Node* *return_size_val) {
3045   // Compute size in doublewords
3046   // The size is always an integral number of doublewords, represented
3047   // as a positive bytewise size stored in the klass's layout_helper.
3048   // The layout_helper also encodes (in a low bit) the need for a slow path.
3049   jint  layout_con = Klass::_lh_neutral_value;
3050   Node* layout_val = get_layout_helper(klass_node, layout_con);
3051   int   layout_is_con = (layout_val == NULL);
3052 
3053   if (extra_slow_test == NULL)  extra_slow_test = intcon(0);
3054   // Generate the initial go-slow test.  It's either ALWAYS (return a
3055   // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective
3056   // case) a computed value derived from the layout_helper.
3057   Node* initial_slow_test = NULL;
3058   if (layout_is_con) {
3059     assert(!StressReflectiveCode, "stress mode does not use these paths");
3060     bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3061     initial_slow_test = must_go_slow? intcon(1): extra_slow_test;
3062 
3063   } else {   // reflective case
3064     // This reflective path is used by Unsafe.allocateInstance.
3065     // (It may be stress-tested by specifying StressReflectiveCode.)
3066     // Basically, we want to get into the VM is there's an illegal argument.
3067     Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3068     initial_slow_test = _gvn.transform( new (C, 3) AndINode(layout_val, bit) );
3069     if (extra_slow_test != intcon(0)) {
3070       initial_slow_test = _gvn.transform( new (C, 3) OrINode(initial_slow_test, extra_slow_test) );
3071     }
3072     // (Macro-expander will further convert this to a Bool, if necessary.)
3073   }
3074 
3075   // Find the size in bytes.  This is easy; it's the layout_helper.
3076   // The size value must be valid even if the slow path is taken.
3077   Node* size = NULL;
3078   if (layout_is_con) {
3079     size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3080   } else {   // reflective case
3081     // This reflective path is used by clone and Unsafe.allocateInstance.
3082     size = ConvI2X(layout_val);
3083 
3084     // Clear the low bits to extract layout_helper_size_in_bytes:
3085     assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3086     Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3087     size = _gvn.transform( new (C, 3) AndXNode(size, mask) );
3088   }
3089   if (return_size_val != NULL) {
3090     (*return_size_val) = size;
3091   }
3092 
3093   // This is a precise notnull oop of the klass.
3094   // (Actually, it need not be precise if this is a reflective allocation.)
3095   // It's what we cast the result to.
3096   const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3097   if (!tklass)  tklass = TypeKlassPtr::OBJECT;
3098   const TypeOopPtr* oop_type = tklass->as_instance_type();
3099 
3100   // Now generate allocation code
3101 
3102   // The entire memory state is needed for slow path of the allocation
3103   // since GC and deoptimization can happened.
3104   Node *mem = reset_memory();
3105   set_all_memory(mem); // Create new memory state
3106 
3107   AllocateNode* alloc
3108     = new (C, AllocateNode::ParmLimit)
3109         AllocateNode(C, AllocateNode::alloc_type(),
3110                      control(), mem, i_o(),
3111                      size, klass_node,
3112                      initial_slow_test);
3113 
3114   return set_output_for_allocation(alloc, oop_type);
3115 }
3116 
3117 //-------------------------------new_array-------------------------------------
3118 // helper for both newarray and anewarray
3119 // The 'length' parameter is (obviously) the length of the array.
3120 // See comments on new_instance for the meaning of the other arguments.
3121 Node* GraphKit::new_array(Node* klass_node,     // array klass (maybe variable)
3122                           Node* length,         // number of array elements
3123                           int   nargs,          // number of arguments to push back for uncommon trap
3124                           Node* *return_size_val) {
3125   jint  layout_con = Klass::_lh_neutral_value;
3126   Node* layout_val = get_layout_helper(klass_node, layout_con);
3127   int   layout_is_con = (layout_val == NULL);
3128 
3129   if (!layout_is_con && !StressReflectiveCode &&
3130       !too_many_traps(Deoptimization::Reason_class_check)) {
3131     // This is a reflective array creation site.
3132     // Optimistically assume that it is a subtype of Object[],
3133     // so that we can fold up all the address arithmetic.
3134     layout_con = Klass::array_layout_helper(T_OBJECT);
3135     Node* cmp_lh = _gvn.transform( new(C, 3) CmpINode(layout_val, intcon(layout_con)) );
3136     Node* bol_lh = _gvn.transform( new(C, 2) BoolNode(cmp_lh, BoolTest::eq) );
3137     { BuildCutout unless(this, bol_lh, PROB_MAX);
3138       _sp += nargs;
3139       uncommon_trap(Deoptimization::Reason_class_check,
3140                     Deoptimization::Action_maybe_recompile);
3141     }
3142     layout_val = NULL;
3143     layout_is_con = true;
3144   }
3145 
3146   // Generate the initial go-slow test.  Make sure we do not overflow
3147   // if length is huge (near 2Gig) or negative!  We do not need
3148   // exact double-words here, just a close approximation of needed
3149   // double-words.  We can't add any offset or rounding bits, lest we
3150   // take a size -1 of bytes and make it positive.  Use an unsigned
3151   // compare, so negative sizes look hugely positive.
3152   int fast_size_limit = FastAllocateSizeLimit;
3153   if (layout_is_con) {
3154     assert(!StressReflectiveCode, "stress mode does not use these paths");
3155     // Increase the size limit if we have exact knowledge of array type.
3156     int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3157     fast_size_limit <<= (LogBytesPerLong - log2_esize);
3158   }
3159 
3160   Node* initial_slow_cmp  = _gvn.transform( new (C, 3) CmpUNode( length, intcon( fast_size_limit ) ) );
3161   Node* initial_slow_test = _gvn.transform( new (C, 2) BoolNode( initial_slow_cmp, BoolTest::gt ) );
3162   if (initial_slow_test->is_Bool()) {
3163     // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3164     initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3165   }
3166 
3167   // --- Size Computation ---
3168   // array_size = round_to_heap(array_header + (length << elem_shift));
3169   // where round_to_heap(x) == round_to(x, MinObjAlignmentInBytes)
3170   // and round_to(x, y) == ((x + y-1) & ~(y-1))
3171   // The rounding mask is strength-reduced, if possible.
3172   int round_mask = MinObjAlignmentInBytes - 1;
3173   Node* header_size = NULL;
3174   int   header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3175   // (T_BYTE has the weakest alignment and size restrictions...)
3176   if (layout_is_con) {
3177     int       hsize  = Klass::layout_helper_header_size(layout_con);
3178     int       eshift = Klass::layout_helper_log2_element_size(layout_con);
3179     BasicType etype  = Klass::layout_helper_element_type(layout_con);
3180     if ((round_mask & ~right_n_bits(eshift)) == 0)
3181       round_mask = 0;  // strength-reduce it if it goes away completely
3182     assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3183     assert(header_size_min <= hsize, "generic minimum is smallest");
3184     header_size_min = hsize;
3185     header_size = intcon(hsize + round_mask);
3186   } else {
3187     Node* hss   = intcon(Klass::_lh_header_size_shift);
3188     Node* hsm   = intcon(Klass::_lh_header_size_mask);
3189     Node* hsize = _gvn.transform( new(C, 3) URShiftINode(layout_val, hss) );
3190     hsize       = _gvn.transform( new(C, 3) AndINode(hsize, hsm) );
3191     Node* mask  = intcon(round_mask);
3192     header_size = _gvn.transform( new(C, 3) AddINode(hsize, mask) );
3193   }
3194 
3195   Node* elem_shift = NULL;
3196   if (layout_is_con) {
3197     int eshift = Klass::layout_helper_log2_element_size(layout_con);
3198     if (eshift != 0)
3199       elem_shift = intcon(eshift);
3200   } else {
3201     // There is no need to mask or shift this value.
3202     // The semantics of LShiftINode include an implicit mask to 0x1F.
3203     assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3204     elem_shift = layout_val;
3205   }
3206 
3207   // Transition to native address size for all offset calculations:
3208   Node* lengthx = ConvI2X(length);
3209   Node* headerx = ConvI2X(header_size);
3210 #ifdef _LP64
3211   { const TypeLong* tllen = _gvn.find_long_type(lengthx);
3212     if (tllen != NULL && tllen->_lo < 0) {
3213       // Add a manual constraint to a positive range.  Cf. array_element_address.
3214       jlong size_max = arrayOopDesc::max_array_length(T_BYTE);
3215       if (size_max > tllen->_hi)  size_max = tllen->_hi;
3216       const TypeLong* tlcon = TypeLong::make(CONST64(0), size_max, Type::WidenMin);
3217       lengthx = _gvn.transform( new (C, 2) ConvI2LNode(length, tlcon));
3218     }
3219   }
3220 #endif
3221 
3222   // Combine header size (plus rounding) and body size.  Then round down.
3223   // This computation cannot overflow, because it is used only in two
3224   // places, one where the length is sharply limited, and the other
3225   // after a successful allocation.
3226   Node* abody = lengthx;
3227   if (elem_shift != NULL)
3228     abody     = _gvn.transform( new(C, 3) LShiftXNode(lengthx, elem_shift) );
3229   Node* size  = _gvn.transform( new(C, 3) AddXNode(headerx, abody) );
3230   if (round_mask != 0) {
3231     Node* mask = MakeConX(~round_mask);
3232     size       = _gvn.transform( new(C, 3) AndXNode(size, mask) );
3233   }
3234   // else if round_mask == 0, the size computation is self-rounding
3235 
3236   if (return_size_val != NULL) {
3237     // This is the size
3238     (*return_size_val) = size;
3239   }
3240 
3241   // Now generate allocation code
3242 
3243   // The entire memory state is needed for slow path of the allocation
3244   // since GC and deoptimization can happened.
3245   Node *mem = reset_memory();
3246   set_all_memory(mem); // Create new memory state
3247 
3248   // Create the AllocateArrayNode and its result projections
3249   AllocateArrayNode* alloc
3250     = new (C, AllocateArrayNode::ParmLimit)
3251         AllocateArrayNode(C, AllocateArrayNode::alloc_type(),
3252                           control(), mem, i_o(),
3253                           size, klass_node,
3254                           initial_slow_test,
3255                           length);
3256 
3257   // Cast to correct type.  Note that the klass_node may be constant or not,
3258   // and in the latter case the actual array type will be inexact also.
3259   // (This happens via a non-constant argument to inline_native_newArray.)
3260   // In any case, the value of klass_node provides the desired array type.
3261   const TypeInt* length_type = _gvn.find_int_type(length);
3262   const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3263   if (ary_type->isa_aryptr() && length_type != NULL) {
3264     // Try to get a better type than POS for the size
3265     ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3266   }
3267 
3268   Node* javaoop = set_output_for_allocation(alloc, ary_type);
3269 
3270   // Cast length on remaining path to be as narrow as possible
3271   if (map()->find_edge(length) >= 0) {
3272     Node* ccast = alloc->make_ideal_length(ary_type, &_gvn);
3273     if (ccast != length) {
3274       _gvn.set_type_bottom(ccast);
3275       record_for_igvn(ccast);
3276       replace_in_map(length, ccast);
3277     }
3278   }
3279 
3280   return javaoop;
3281 }
3282 
3283 // The following "Ideal_foo" functions are placed here because they recognize
3284 // the graph shapes created by the functions immediately above.
3285 
3286 //---------------------------Ideal_allocation----------------------------------
3287 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3288 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) {
3289   if (ptr == NULL) {     // reduce dumb test in callers
3290     return NULL;
3291   }
3292   if (ptr->is_CheckCastPP()) {  // strip a raw-to-oop cast
3293     ptr = ptr->in(1);
3294     if (ptr == NULL)  return NULL;
3295   }
3296   if (ptr->is_Proj()) {
3297     Node* allo = ptr->in(0);
3298     if (allo != NULL && allo->is_Allocate()) {
3299       return allo->as_Allocate();
3300     }
3301   }
3302   // Report failure to match.
3303   return NULL;
3304 }
3305 
3306 // Fancy version which also strips off an offset (and reports it to caller).
3307 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase,
3308                                              intptr_t& offset) {
3309   Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
3310   if (base == NULL)  return NULL;
3311   return Ideal_allocation(base, phase);
3312 }
3313 
3314 // Trace Initialize <- Proj[Parm] <- Allocate
3315 AllocateNode* InitializeNode::allocation() {
3316   Node* rawoop = in(InitializeNode::RawAddress);
3317   if (rawoop->is_Proj()) {
3318     Node* alloc = rawoop->in(0);
3319     if (alloc->is_Allocate()) {
3320       return alloc->as_Allocate();
3321     }
3322   }
3323   return NULL;
3324 }
3325 
3326 // Trace Allocate -> Proj[Parm] -> Initialize
3327 InitializeNode* AllocateNode::initialization() {
3328   ProjNode* rawoop = proj_out(AllocateNode::RawAddress);
3329   if (rawoop == NULL)  return NULL;
3330   for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3331     Node* init = rawoop->fast_out(i);
3332     if (init->is_Initialize()) {
3333       assert(init->as_Initialize()->allocation() == this, "2-way link");
3334       return init->as_Initialize();
3335     }
3336   }
3337   return NULL;
3338 }
3339 
3340 // Trace Allocate -> Proj[Parm] -> MemBarStoreStore
3341 MemBarStoreStoreNode* AllocateNode::storestore() {
3342   ProjNode* rawoop = proj_out(AllocateNode::RawAddress);
3343   if (rawoop == NULL)  return NULL;
3344   for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3345     Node* storestore = rawoop->fast_out(i);
3346     if (storestore->is_MemBarStoreStore()) {
3347       return storestore->as_MemBarStoreStore();
3348     }
3349   }
3350   return NULL;
3351 }
3352 
3353 //----------------------------- loop predicates ---------------------------
3354 
3355 //------------------------------add_predicate_impl----------------------------
3356 void GraphKit::add_predicate_impl(Deoptimization::DeoptReason reason, int nargs) {
3357   // Too many traps seen?
3358   if (too_many_traps(reason)) {
3359 #ifdef ASSERT
3360     if (TraceLoopPredicate) {
3361       int tc = C->trap_count(reason);
3362       tty->print("too many traps=%s tcount=%d in ",
3363                     Deoptimization::trap_reason_name(reason), tc);
3364       method()->print(); // which method has too many predicate traps
3365       tty->cr();
3366     }
3367 #endif
3368     // We cannot afford to take more traps here,
3369     // do not generate predicate.
3370     return;
3371   }
3372 
3373   Node *cont    = _gvn.intcon(1);
3374   Node* opq     = _gvn.transform(new (C, 2) Opaque1Node(C, cont));
3375   Node *bol     = _gvn.transform(new (C, 2) Conv2BNode(opq));
3376   IfNode* iff   = create_and_map_if(control(), bol, PROB_MAX, COUNT_UNKNOWN);
3377   Node* iffalse = _gvn.transform(new (C, 1) IfFalseNode(iff));
3378   C->add_predicate_opaq(opq);
3379   {
3380     PreserveJVMState pjvms(this);
3381     set_control(iffalse);
3382     _sp += nargs;
3383     uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
3384   }
3385   Node* iftrue = _gvn.transform(new (C, 1) IfTrueNode(iff));
3386   set_control(iftrue);
3387 }
3388 
3389 //------------------------------add_predicate---------------------------------
3390 void GraphKit::add_predicate(int nargs) {
3391   if (UseLoopPredicate) {
3392     add_predicate_impl(Deoptimization::Reason_predicate, nargs);
3393   }
3394   // loop's limit check predicate should be near the loop.
3395   if (LoopLimitCheck) {
3396     add_predicate_impl(Deoptimization::Reason_loop_limit_check, nargs);
3397   }
3398 }
3399 
3400 //----------------------------- store barriers ----------------------------
3401 #define __ ideal.
3402 
3403 void GraphKit::sync_kit(IdealKit& ideal) {
3404   set_all_memory(__ merged_memory());
3405   set_i_o(__ i_o());
3406   set_control(__ ctrl());
3407 }
3408 
3409 void GraphKit::final_sync(IdealKit& ideal) {
3410   // Final sync IdealKit and graphKit.
3411   __ drain_delay_transform();
3412   sync_kit(ideal);
3413 }
3414 
3415 // vanilla/CMS post barrier
3416 // Insert a write-barrier store.  This is to let generational GC work; we have
3417 // to flag all oop-stores before the next GC point.
3418 void GraphKit::write_barrier_post(Node* oop_store,
3419                                   Node* obj,
3420                                   Node* adr,
3421                                   uint  adr_idx,
3422                                   Node* val,
3423                                   bool use_precise) {
3424   // No store check needed if we're storing a NULL or an old object
3425   // (latter case is probably a string constant). The concurrent
3426   // mark sweep garbage collector, however, needs to have all nonNull
3427   // oop updates flagged via card-marks.
3428   if (val != NULL && val->is_Con()) {
3429     // must be either an oop or NULL
3430     const Type* t = val->bottom_type();
3431     if (t == TypePtr::NULL_PTR || t == Type::TOP)
3432       // stores of null never (?) need barriers
3433       return;
3434     ciObject* con = t->is_oopptr()->const_oop();
3435     if (con != NULL
3436         && con->is_perm()
3437         && Universe::heap()->can_elide_permanent_oop_store_barriers())
3438       // no store barrier needed, because no old-to-new ref created
3439       return;
3440   }
3441 
3442   if (use_ReduceInitialCardMarks()
3443       && obj == just_allocated_object(control())) {
3444     // We can skip marks on a freshly-allocated object in Eden.
3445     // Keep this code in sync with new_store_pre_barrier() in runtime.cpp.
3446     // That routine informs GC to take appropriate compensating steps,
3447     // upon a slow-path allocation, so as to make this card-mark
3448     // elision safe.
3449     return;
3450   }
3451 
3452   if (!use_precise) {
3453     // All card marks for a (non-array) instance are in one place:
3454     adr = obj;
3455   }
3456   // (Else it's an array (or unknown), and we want more precise card marks.)
3457   assert(adr != NULL, "");
3458 
3459   IdealKit ideal(this, true);
3460 
3461   // Convert the pointer to an int prior to doing math on it
3462   Node* cast = __ CastPX(__ ctrl(), adr);
3463 
3464   // Divide by card size
3465   assert(Universe::heap()->barrier_set()->kind() == BarrierSet::CardTableModRef,
3466          "Only one we handle so far.");
3467   Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3468 
3469   // Combine card table base and card offset
3470   Node* card_adr = __ AddP(__ top(), byte_map_base_node(), card_offset );
3471 
3472   // Get the alias_index for raw card-mark memory
3473   int adr_type = Compile::AliasIdxRaw;
3474   Node*   zero = __ ConI(0); // Dirty card value
3475   BasicType bt = T_BYTE;
3476 
3477   if (UseCondCardMark) {
3478     // The classic GC reference write barrier is typically implemented
3479     // as a store into the global card mark table.  Unfortunately
3480     // unconditional stores can result in false sharing and excessive
3481     // coherence traffic as well as false transactional aborts.
3482     // UseCondCardMark enables MP "polite" conditional card mark
3483     // stores.  In theory we could relax the load from ctrl() to
3484     // no_ctrl, but that doesn't buy much latitude.
3485     Node* card_val = __ load( __ ctrl(), card_adr, TypeInt::BYTE, bt, adr_type);
3486     __ if_then(card_val, BoolTest::ne, zero);
3487   }
3488 
3489   // Smash zero into card
3490   if( !UseConcMarkSweepGC ) {
3491     __ store(__ ctrl(), card_adr, zero, bt, adr_type);
3492   } else {
3493     // Specialized path for CM store barrier
3494     __ storeCM(__ ctrl(), card_adr, zero, oop_store, adr_idx, bt, adr_type);
3495   }
3496 
3497   if (UseCondCardMark) {
3498     __ end_if();
3499   }
3500 
3501   // Final sync IdealKit and GraphKit.
3502   final_sync(ideal);
3503 }
3504 
3505 // G1 pre/post barriers
3506 void GraphKit::g1_write_barrier_pre(bool do_load,
3507                                     Node* obj,
3508                                     Node* adr,
3509                                     uint alias_idx,
3510                                     Node* val,
3511                                     const TypeOopPtr* val_type,
3512                                     Node* pre_val,
3513                                     BasicType bt) {
3514 
3515   // Some sanity checks
3516   // Note: val is unused in this routine.
3517 
3518   if (do_load) {
3519     // We need to generate the load of the previous value
3520     assert(obj != NULL, "must have a base");
3521     assert(adr != NULL, "where are loading from?");
3522     assert(pre_val == NULL, "loaded already?");
3523     assert(val_type != NULL, "need a type");
3524   } else {
3525     // In this case both val_type and alias_idx are unused.
3526     assert(pre_val != NULL, "must be loaded already");
3527     assert(pre_val->bottom_type()->basic_type() == T_OBJECT, "or we shouldn't be here");
3528   }
3529   assert(bt == T_OBJECT, "or we shouldn't be here");
3530 
3531   IdealKit ideal(this, true);
3532 
3533   Node* tls = __ thread(); // ThreadLocalStorage
3534 
3535   Node* no_ctrl = NULL;
3536   Node* no_base = __ top();
3537   Node* zero = __ ConI(0);
3538 
3539   float likely  = PROB_LIKELY(0.999);
3540   float unlikely  = PROB_UNLIKELY(0.999);
3541 
3542   BasicType active_type = in_bytes(PtrQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE;
3543   assert(in_bytes(PtrQueue::byte_width_of_active()) == 4 || in_bytes(PtrQueue::byte_width_of_active()) == 1, "flag width");
3544 
3545   // Offsets into the thread
3546   const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() +  // 648
3547                                           PtrQueue::byte_offset_of_active());
3548   const int index_offset   = in_bytes(JavaThread::satb_mark_queue_offset() +  // 656
3549                                           PtrQueue::byte_offset_of_index());
3550   const int buffer_offset  = in_bytes(JavaThread::satb_mark_queue_offset() +  // 652
3551                                           PtrQueue::byte_offset_of_buf());
3552 
3553   // Now the actual pointers into the thread
3554   Node* marking_adr = __ AddP(no_base, tls, __ ConX(marking_offset));
3555   Node* buffer_adr  = __ AddP(no_base, tls, __ ConX(buffer_offset));
3556   Node* index_adr   = __ AddP(no_base, tls, __ ConX(index_offset));
3557 
3558   // Now some of the values
3559   Node* marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw);
3560 
3561   // if (!marking)
3562   __ if_then(marking, BoolTest::ne, zero); {
3563     Node* index   = __ load(__ ctrl(), index_adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw);
3564 
3565     if (do_load) {
3566       // load original value
3567       // alias_idx correct??
3568       pre_val = __ load(no_ctrl, adr, val_type, bt, alias_idx);
3569     }
3570 
3571     // if (pre_val != NULL)
3572     __ if_then(pre_val, BoolTest::ne, null()); {
3573       Node* buffer  = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
3574 
3575       // is the queue for this thread full?
3576       __ if_then(index, BoolTest::ne, zero, likely); {
3577 
3578         // decrement the index
3579         Node* next_index = __ SubI(index,  __ ConI(sizeof(intptr_t)));
3580         Node* next_indexX = next_index;
3581 #ifdef _LP64
3582         // We could refine the type for what it's worth
3583         // const TypeLong* lidxtype = TypeLong::make(CONST64(0), get_size_from_queue);
3584         next_indexX = _gvn.transform( new (C, 2) ConvI2LNode(next_index, TypeLong::make(0, max_jlong, Type::WidenMax)) );
3585 #endif
3586 
3587         // Now get the buffer location we will log the previous value into and store it
3588         Node *log_addr = __ AddP(no_base, buffer, next_indexX);
3589         __ store(__ ctrl(), log_addr, pre_val, T_OBJECT, Compile::AliasIdxRaw);
3590         // update the index
3591         __ store(__ ctrl(), index_adr, next_index, T_INT, Compile::AliasIdxRaw);
3592 
3593       } __ else_(); {
3594 
3595         // logging buffer is full, call the runtime
3596         const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type();
3597         __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", pre_val, tls);
3598       } __ end_if();  // (!index)
3599     } __ end_if();  // (pre_val != NULL)
3600   } __ end_if();  // (!marking)
3601 
3602   // Final sync IdealKit and GraphKit.
3603   final_sync(ideal);
3604 }
3605 
3606 //
3607 // Update the card table and add card address to the queue
3608 //
3609 void GraphKit::g1_mark_card(IdealKit& ideal,
3610                             Node* card_adr,
3611                             Node* oop_store,
3612                             uint oop_alias_idx,
3613                             Node* index,
3614                             Node* index_adr,
3615                             Node* buffer,
3616                             const TypeFunc* tf) {
3617 
3618   Node* zero = __ ConI(0);
3619   Node* no_base = __ top();
3620   BasicType card_bt = T_BYTE;
3621   // Smash zero into card. MUST BE ORDERED WRT TO STORE
3622   __ storeCM(__ ctrl(), card_adr, zero, oop_store, oop_alias_idx, card_bt, Compile::AliasIdxRaw);
3623 
3624   //  Now do the queue work
3625   __ if_then(index, BoolTest::ne, zero); {
3626 
3627     Node* next_index = __ SubI(index, __ ConI(sizeof(intptr_t)));
3628     Node* next_indexX = next_index;
3629 #ifdef _LP64
3630     // We could refine the type for what it's worth
3631     // const TypeLong* lidxtype = TypeLong::make(CONST64(0), get_size_from_queue);
3632     next_indexX = _gvn.transform( new (C, 2) ConvI2LNode(next_index, TypeLong::make(0, max_jlong, Type::WidenMax)) );
3633 #endif // _LP64
3634     Node* log_addr = __ AddP(no_base, buffer, next_indexX);
3635 
3636     __ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw);
3637     __ store(__ ctrl(), index_adr, next_index, T_INT, Compile::AliasIdxRaw);
3638 
3639   } __ else_(); {
3640     __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread());
3641   } __ end_if();
3642 
3643 }
3644 
3645 void GraphKit::g1_write_barrier_post(Node* oop_store,
3646                                      Node* obj,
3647                                      Node* adr,
3648                                      uint alias_idx,
3649                                      Node* val,
3650                                      BasicType bt,
3651                                      bool use_precise) {
3652   // If we are writing a NULL then we need no post barrier
3653 
3654   if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) {
3655     // Must be NULL
3656     const Type* t = val->bottom_type();
3657     assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL");
3658     // No post barrier if writing NULLx
3659     return;
3660   }
3661 
3662   if (!use_precise) {
3663     // All card marks for a (non-array) instance are in one place:
3664     adr = obj;
3665   }
3666   // (Else it's an array (or unknown), and we want more precise card marks.)
3667   assert(adr != NULL, "");
3668 
3669   IdealKit ideal(this, true);
3670 
3671   Node* tls = __ thread(); // ThreadLocalStorage
3672 
3673   Node* no_base = __ top();
3674   float likely  = PROB_LIKELY(0.999);
3675   float unlikely  = PROB_UNLIKELY(0.999);
3676   Node* zero = __ ConI(0);
3677   Node* zeroX = __ ConX(0);
3678 
3679   // Get the alias_index for raw card-mark memory
3680   const TypePtr* card_type = TypeRawPtr::BOTTOM;
3681 
3682   const TypeFunc *tf = OptoRuntime::g1_wb_post_Type();
3683 
3684   // Offsets into the thread
3685   const int index_offset  = in_bytes(JavaThread::dirty_card_queue_offset() +
3686                                      PtrQueue::byte_offset_of_index());
3687   const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
3688                                      PtrQueue::byte_offset_of_buf());
3689 
3690   // Pointers into the thread
3691 
3692   Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
3693   Node* index_adr =  __ AddP(no_base, tls, __ ConX(index_offset));
3694 
3695   // Now some values
3696   // Use ctrl to avoid hoisting these values past a safepoint, which could
3697   // potentially reset these fields in the JavaThread.
3698   Node* index  = __ load(__ ctrl(), index_adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw);
3699   Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
3700 
3701   // Convert the store obj pointer to an int prior to doing math on it
3702   // Must use ctrl to prevent "integerized oop" existing across safepoint
3703   Node* cast =  __ CastPX(__ ctrl(), adr);
3704 
3705   // Divide pointer by card size
3706   Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3707 
3708   // Combine card table base and card offset
3709   Node* card_adr = __ AddP(no_base, byte_map_base_node(), card_offset );
3710 
3711   // If we know the value being stored does it cross regions?
3712 
3713   if (val != NULL) {
3714     // Does the store cause us to cross regions?
3715 
3716     // Should be able to do an unsigned compare of region_size instead of
3717     // and extra shift. Do we have an unsigned compare??
3718     // Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes);
3719     Node* xor_res =  __ URShiftX ( __ XorX( cast,  __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes));
3720 
3721     // if (xor_res == 0) same region so skip
3722     __ if_then(xor_res, BoolTest::ne, zeroX); {
3723 
3724       // No barrier if we are storing a NULL
3725       __ if_then(val, BoolTest::ne, null(), unlikely); {
3726 
3727         // Ok must mark the card if not already dirty
3728 
3729         // load the original value of the card
3730         Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
3731 
3732         __ if_then(card_val, BoolTest::ne, zero); {
3733           g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
3734         } __ end_if();
3735       } __ end_if();
3736     } __ end_if();
3737   } else {
3738     // Object.clone() instrinsic uses this path.
3739     g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
3740   }
3741 
3742   // Final sync IdealKit and GraphKit.
3743   final_sync(ideal);
3744 }
3745 #undef __