1 /*
   2  * Copyright (c) 2001, 2015, 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 "ci/ciValueKlass.hpp"
  28 #include "gc/g1/g1SATBCardTableModRefBS.hpp"
  29 #include "gc/g1/heapRegion.hpp"
  30 #include "gc/shared/barrierSet.hpp"
  31 #include "gc/shared/cardTableModRefBS.hpp"
  32 #include "gc/shared/collectedHeap.hpp"
  33 #include "opto/addnode.hpp"
  34 #include "opto/castnode.hpp"
  35 #include "opto/convertnode.hpp"
  36 #include "opto/graphKit.hpp"
  37 #include "opto/idealKit.hpp"
  38 #include "opto/intrinsicnode.hpp"
  39 #include "opto/locknode.hpp"
  40 #include "opto/machnode.hpp"
  41 #include "opto/opaquenode.hpp"
  42 #include "opto/parse.hpp"
  43 #include "opto/rootnode.hpp"
  44 #include "opto/runtime.hpp"
  45 #include "opto/valuetypenode.hpp"
  46 #include "runtime/deoptimization.hpp"
  47 #include "runtime/sharedRuntime.hpp"
  48 
  49 //----------------------------GraphKit-----------------------------------------
  50 // Main utility constructor.
  51 GraphKit::GraphKit(JVMState* jvms)
  52   : Phase(Phase::Parser),
  53     _env(C->env()),
  54     _gvn(*C->initial_gvn())
  55 {
  56   _exceptions = jvms->map()->next_exception();
  57   if (_exceptions != NULL)  jvms->map()->set_next_exception(NULL);
  58   set_jvms(jvms);
  59 }
  60 
  61 // Private constructor for parser.
  62 GraphKit::GraphKit()
  63   : Phase(Phase::Parser),
  64     _env(C->env()),
  65     _gvn(*C->initial_gvn())
  66 {
  67   _exceptions = NULL;
  68   set_map(NULL);
  69   debug_only(_sp = -99);
  70   debug_only(set_bci(-99));
  71 }
  72 
  73 
  74 
  75 //---------------------------clean_stack---------------------------------------
  76 // Clear away rubbish from the stack area of the JVM state.
  77 // This destroys any arguments that may be waiting on the stack.
  78 void GraphKit::clean_stack(int from_sp) {
  79   SafePointNode* map      = this->map();
  80   JVMState*      jvms     = this->jvms();
  81   int            stk_size = jvms->stk_size();
  82   int            stkoff   = jvms->stkoff();
  83   Node*          top      = this->top();
  84   for (int i = from_sp; i < stk_size; i++) {
  85     if (map->in(stkoff + i) != top) {
  86       map->set_req(stkoff + i, top);
  87     }
  88   }
  89 }
  90 
  91 
  92 //--------------------------------sync_jvms-----------------------------------
  93 // Make sure our current jvms agrees with our parse state.
  94 JVMState* GraphKit::sync_jvms() const {
  95   JVMState* jvms = this->jvms();
  96   jvms->set_bci(bci());       // Record the new bci in the JVMState
  97   jvms->set_sp(sp());         // Record the new sp in the JVMState
  98   assert(jvms_in_sync(), "jvms is now in sync");
  99   return jvms;
 100 }
 101 
 102 //--------------------------------sync_jvms_for_reexecute---------------------
 103 // Make sure our current jvms agrees with our parse state.  This version
 104 // uses the reexecute_sp for reexecuting bytecodes.
 105 JVMState* GraphKit::sync_jvms_for_reexecute() {
 106   JVMState* jvms = this->jvms();
 107   jvms->set_bci(bci());          // Record the new bci in the JVMState
 108   jvms->set_sp(reexecute_sp());  // Record the new sp in the JVMState
 109   return jvms;
 110 }
 111 
 112 #ifdef ASSERT
 113 bool GraphKit::jvms_in_sync() const {
 114   Parse* parse = is_Parse();
 115   if (parse == NULL) {
 116     if (bci() !=      jvms()->bci())          return false;
 117     if (sp()  != (int)jvms()->sp())           return false;
 118     return true;
 119   }
 120   if (jvms()->method() != parse->method())    return false;
 121   if (jvms()->bci()    != parse->bci())       return false;
 122   int jvms_sp = jvms()->sp();
 123   if (jvms_sp          != parse->sp())        return false;
 124   int jvms_depth = jvms()->depth();
 125   if (jvms_depth       != parse->depth())     return false;
 126   return true;
 127 }
 128 
 129 // Local helper checks for special internal merge points
 130 // used to accumulate and merge exception states.
 131 // They are marked by the region's in(0) edge being the map itself.
 132 // Such merge points must never "escape" into the parser at large,
 133 // until they have been handed to gvn.transform.
 134 static bool is_hidden_merge(Node* reg) {
 135   if (reg == NULL)  return false;
 136   if (reg->is_Phi()) {
 137     reg = reg->in(0);
 138     if (reg == NULL)  return false;
 139   }
 140   return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root();
 141 }
 142 
 143 void GraphKit::verify_map() const {
 144   if (map() == NULL)  return;  // null map is OK
 145   assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
 146   assert(!map()->has_exceptions(),    "call add_exception_states_from 1st");
 147   assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
 148 }
 149 
 150 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
 151   assert(ex_map->next_exception() == NULL, "not already part of a chain");
 152   assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
 153 }
 154 #endif
 155 
 156 //---------------------------stop_and_kill_map---------------------------------
 157 // Set _map to NULL, signalling a stop to further bytecode execution.
 158 // First smash the current map's control to a constant, to mark it dead.
 159 void GraphKit::stop_and_kill_map() {
 160   SafePointNode* dead_map = stop();
 161   if (dead_map != NULL) {
 162     dead_map->disconnect_inputs(NULL, C); // Mark the map as killed.
 163     assert(dead_map->is_killed(), "must be so marked");
 164   }
 165 }
 166 
 167 
 168 //--------------------------------stopped--------------------------------------
 169 // Tell if _map is NULL, or control is top.
 170 bool GraphKit::stopped() {
 171   if (map() == NULL)           return true;
 172   else if (control() == top()) return true;
 173   else                         return false;
 174 }
 175 
 176 
 177 //-----------------------------has_ex_handler----------------------------------
 178 // Tell if this method or any caller method has exception handlers.
 179 bool GraphKit::has_ex_handler() {
 180   for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) {
 181     if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
 182       return true;
 183     }
 184   }
 185   return false;
 186 }
 187 
 188 //------------------------------save_ex_oop------------------------------------
 189 // Save an exception without blowing stack contents or other JVM state.
 190 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
 191   assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
 192   ex_map->add_req(ex_oop);
 193   debug_only(verify_exception_state(ex_map));
 194 }
 195 
 196 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
 197   assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
 198   Node* ex_oop = ex_map->in(ex_map->req()-1);
 199   if (clear_it)  ex_map->del_req(ex_map->req()-1);
 200   return ex_oop;
 201 }
 202 
 203 //-----------------------------saved_ex_oop------------------------------------
 204 // Recover a saved exception from its map.
 205 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
 206   return common_saved_ex_oop(ex_map, false);
 207 }
 208 
 209 //--------------------------clear_saved_ex_oop---------------------------------
 210 // Erase a previously saved exception from its map.
 211 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
 212   return common_saved_ex_oop(ex_map, true);
 213 }
 214 
 215 #ifdef ASSERT
 216 //---------------------------has_saved_ex_oop----------------------------------
 217 // Erase a previously saved exception from its map.
 218 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
 219   return ex_map->req() == ex_map->jvms()->endoff()+1;
 220 }
 221 #endif
 222 
 223 //-------------------------make_exception_state--------------------------------
 224 // Turn the current JVM state into an exception state, appending the ex_oop.
 225 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
 226   sync_jvms();
 227   SafePointNode* ex_map = stop();  // do not manipulate this map any more
 228   set_saved_ex_oop(ex_map, ex_oop);
 229   return ex_map;
 230 }
 231 
 232 
 233 //--------------------------add_exception_state--------------------------------
 234 // Add an exception to my list of exceptions.
 235 void GraphKit::add_exception_state(SafePointNode* ex_map) {
 236   if (ex_map == NULL || ex_map->control() == top()) {
 237     return;
 238   }
 239 #ifdef ASSERT
 240   verify_exception_state(ex_map);
 241   if (has_exceptions()) {
 242     assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
 243   }
 244 #endif
 245 
 246   // If there is already an exception of exactly this type, merge with it.
 247   // In particular, null-checks and other low-level exceptions common up here.
 248   Node*       ex_oop  = saved_ex_oop(ex_map);
 249   const Type* ex_type = _gvn.type(ex_oop);
 250   if (ex_oop == top()) {
 251     // No action needed.
 252     return;
 253   }
 254   assert(ex_type->isa_instptr(), "exception must be an instance");
 255   for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) {
 256     const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
 257     // We check sp also because call bytecodes can generate exceptions
 258     // both before and after arguments are popped!
 259     if (ex_type2 == ex_type
 260         && e2->_jvms->sp() == ex_map->_jvms->sp()) {
 261       combine_exception_states(ex_map, e2);
 262       return;
 263     }
 264   }
 265 
 266   // No pre-existing exception of the same type.  Chain it on the list.
 267   push_exception_state(ex_map);
 268 }
 269 
 270 //-----------------------add_exception_states_from-----------------------------
 271 void GraphKit::add_exception_states_from(JVMState* jvms) {
 272   SafePointNode* ex_map = jvms->map()->next_exception();
 273   if (ex_map != NULL) {
 274     jvms->map()->set_next_exception(NULL);
 275     for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) {
 276       next_map = ex_map->next_exception();
 277       ex_map->set_next_exception(NULL);
 278       add_exception_state(ex_map);
 279     }
 280   }
 281 }
 282 
 283 //-----------------------transfer_exceptions_into_jvms-------------------------
 284 JVMState* GraphKit::transfer_exceptions_into_jvms() {
 285   if (map() == NULL) {
 286     // We need a JVMS to carry the exceptions, but the map has gone away.
 287     // Create a scratch JVMS, cloned from any of the exception states...
 288     if (has_exceptions()) {
 289       _map = _exceptions;
 290       _map = clone_map();
 291       _map->set_next_exception(NULL);
 292       clear_saved_ex_oop(_map);
 293       debug_only(verify_map());
 294     } else {
 295       // ...or created from scratch
 296       JVMState* jvms = new (C) JVMState(_method, NULL);
 297       jvms->set_bci(_bci);
 298       jvms->set_sp(_sp);
 299       jvms->set_map(new SafePointNode(TypeFunc::Parms, jvms));
 300       set_jvms(jvms);
 301       for (uint i = 0; i < map()->req(); i++)  map()->init_req(i, top());
 302       set_all_memory(top());
 303       while (map()->req() < jvms->endoff())  map()->add_req(top());
 304     }
 305     // (This is a kludge, in case you didn't notice.)
 306     set_control(top());
 307   }
 308   JVMState* jvms = sync_jvms();
 309   assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
 310   jvms->map()->set_next_exception(_exceptions);
 311   _exceptions = NULL;   // done with this set of exceptions
 312   return jvms;
 313 }
 314 
 315 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
 316   assert(is_hidden_merge(dstphi), "must be a special merge node");
 317   assert(is_hidden_merge(srcphi), "must be a special merge node");
 318   uint limit = srcphi->req();
 319   for (uint i = PhiNode::Input; i < limit; i++) {
 320     dstphi->add_req(srcphi->in(i));
 321   }
 322 }
 323 static inline void add_one_req(Node* dstphi, Node* src) {
 324   assert(is_hidden_merge(dstphi), "must be a special merge node");
 325   assert(!is_hidden_merge(src), "must not be a special merge node");
 326   dstphi->add_req(src);
 327 }
 328 
 329 //-----------------------combine_exception_states------------------------------
 330 // This helper function combines exception states by building phis on a
 331 // specially marked state-merging region.  These regions and phis are
 332 // untransformed, and can build up gradually.  The region is marked by
 333 // having a control input of its exception map, rather than NULL.  Such
 334 // regions do not appear except in this function, and in use_exception_state.
 335 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
 336   if (failing())  return;  // dying anyway...
 337   JVMState* ex_jvms = ex_map->_jvms;
 338   assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
 339   assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
 340   assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
 341   assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
 342   assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects");
 343   assert(ex_map->req() == phi_map->req(), "matching maps");
 344   uint tos = ex_jvms->stkoff() + ex_jvms->sp();
 345   Node*         hidden_merge_mark = root();
 346   Node*         region  = phi_map->control();
 347   MergeMemNode* phi_mem = phi_map->merged_memory();
 348   MergeMemNode* ex_mem  = ex_map->merged_memory();
 349   if (region->in(0) != hidden_merge_mark) {
 350     // The control input is not (yet) a specially-marked region in phi_map.
 351     // Make it so, and build some phis.
 352     region = new RegionNode(2);
 353     _gvn.set_type(region, Type::CONTROL);
 354     region->set_req(0, hidden_merge_mark);  // marks an internal ex-state
 355     region->init_req(1, phi_map->control());
 356     phi_map->set_control(region);
 357     Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
 358     record_for_igvn(io_phi);
 359     _gvn.set_type(io_phi, Type::ABIO);
 360     phi_map->set_i_o(io_phi);
 361     for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
 362       Node* m = mms.memory();
 363       Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
 364       record_for_igvn(m_phi);
 365       _gvn.set_type(m_phi, Type::MEMORY);
 366       mms.set_memory(m_phi);
 367     }
 368   }
 369 
 370   // Either or both of phi_map and ex_map might already be converted into phis.
 371   Node* ex_control = ex_map->control();
 372   // if there is special marking on ex_map also, we add multiple edges from src
 373   bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
 374   // how wide was the destination phi_map, originally?
 375   uint orig_width = region->req();
 376 
 377   if (add_multiple) {
 378     add_n_reqs(region, ex_control);
 379     add_n_reqs(phi_map->i_o(), ex_map->i_o());
 380   } else {
 381     // ex_map has no merges, so we just add single edges everywhere
 382     add_one_req(region, ex_control);
 383     add_one_req(phi_map->i_o(), ex_map->i_o());
 384   }
 385   for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
 386     if (mms.is_empty()) {
 387       // get a copy of the base memory, and patch some inputs into it
 388       const TypePtr* adr_type = mms.adr_type(C);
 389       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
 390       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
 391       mms.set_memory(phi);
 392       // Prepare to append interesting stuff onto the newly sliced phi:
 393       while (phi->req() > orig_width)  phi->del_req(phi->req()-1);
 394     }
 395     // Append stuff from ex_map:
 396     if (add_multiple) {
 397       add_n_reqs(mms.memory(), mms.memory2());
 398     } else {
 399       add_one_req(mms.memory(), mms.memory2());
 400     }
 401   }
 402   uint limit = ex_map->req();
 403   for (uint i = TypeFunc::Parms; i < limit; i++) {
 404     // Skip everything in the JVMS after tos.  (The ex_oop follows.)
 405     if (i == tos)  i = ex_jvms->monoff();
 406     Node* src = ex_map->in(i);
 407     Node* dst = phi_map->in(i);
 408     if (src != dst) {
 409       PhiNode* phi;
 410       if (dst->in(0) != region) {
 411         dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
 412         record_for_igvn(phi);
 413         _gvn.set_type(phi, phi->type());
 414         phi_map->set_req(i, dst);
 415         // Prepare to append interesting stuff onto the new phi:
 416         while (dst->req() > orig_width)  dst->del_req(dst->req()-1);
 417       } else {
 418         assert(dst->is_Phi(), "nobody else uses a hidden region");
 419         phi = dst->as_Phi();
 420       }
 421       if (add_multiple && src->in(0) == ex_control) {
 422         // Both are phis.
 423         add_n_reqs(dst, src);
 424       } else {
 425         while (dst->req() < region->req())  add_one_req(dst, src);
 426       }
 427       const Type* srctype = _gvn.type(src);
 428       if (phi->type() != srctype) {
 429         const Type* dsttype = phi->type()->meet_speculative(srctype);
 430         if (phi->type() != dsttype) {
 431           phi->set_type(dsttype);
 432           _gvn.set_type(phi, dsttype);
 433         }
 434       }
 435     }
 436   }
 437   phi_map->merge_replaced_nodes_with(ex_map);
 438 }
 439 
 440 //--------------------------use_exception_state--------------------------------
 441 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
 442   if (failing()) { stop(); return top(); }
 443   Node* region = phi_map->control();
 444   Node* hidden_merge_mark = root();
 445   assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
 446   Node* ex_oop = clear_saved_ex_oop(phi_map);
 447   if (region->in(0) == hidden_merge_mark) {
 448     // Special marking for internal ex-states.  Process the phis now.
 449     region->set_req(0, region);  // now it's an ordinary region
 450     set_jvms(phi_map->jvms());   // ...so now we can use it as a map
 451     // Note: Setting the jvms also sets the bci and sp.
 452     set_control(_gvn.transform(region));
 453     uint tos = jvms()->stkoff() + sp();
 454     for (uint i = 1; i < tos; i++) {
 455       Node* x = phi_map->in(i);
 456       if (x->in(0) == region) {
 457         assert(x->is_Phi(), "expected a special phi");
 458         phi_map->set_req(i, _gvn.transform(x));
 459       }
 460     }
 461     for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
 462       Node* x = mms.memory();
 463       if (x->in(0) == region) {
 464         assert(x->is_Phi(), "nobody else uses a hidden region");
 465         mms.set_memory(_gvn.transform(x));
 466       }
 467     }
 468     if (ex_oop->in(0) == region) {
 469       assert(ex_oop->is_Phi(), "expected a special phi");
 470       ex_oop = _gvn.transform(ex_oop);
 471     }
 472   } else {
 473     set_jvms(phi_map->jvms());
 474   }
 475 
 476   assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
 477   assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
 478   return ex_oop;
 479 }
 480 
 481 //---------------------------------java_bc-------------------------------------
 482 Bytecodes::Code GraphKit::java_bc() const {
 483   ciMethod* method = this->method();
 484   int       bci    = this->bci();
 485   if (method != NULL && bci != InvocationEntryBci)
 486     return method->java_code_at_bci(bci);
 487   else
 488     return Bytecodes::_illegal;
 489 }
 490 
 491 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
 492                                                           bool must_throw) {
 493     // if the exception capability is set, then we will generate code
 494     // to check the JavaThread.should_post_on_exceptions flag to see
 495     // if we actually need to report exception events (for this
 496     // thread).  If we don't need to report exception events, we will
 497     // take the normal fast path provided by add_exception_events.  If
 498     // exception event reporting is enabled for this thread, we will
 499     // take the uncommon_trap in the BuildCutout below.
 500 
 501     // first must access the should_post_on_exceptions_flag in this thread's JavaThread
 502     Node* jthread = _gvn.transform(new ThreadLocalNode());
 503     Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
 504     Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw, MemNode::unordered);
 505 
 506     // Test the should_post_on_exceptions_flag vs. 0
 507     Node* chk = _gvn.transform( new CmpINode(should_post_flag, intcon(0)) );
 508     Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
 509 
 510     // Branch to slow_path if should_post_on_exceptions_flag was true
 511     { BuildCutout unless(this, tst, PROB_MAX);
 512       // Do not try anything fancy if we're notifying the VM on every throw.
 513       // Cf. case Bytecodes::_athrow in parse2.cpp.
 514       uncommon_trap(reason, Deoptimization::Action_none,
 515                     (ciKlass*)NULL, (char*)NULL, must_throw);
 516     }
 517 
 518 }
 519 
 520 //------------------------------builtin_throw----------------------------------
 521 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) {
 522   bool must_throw = true;
 523 
 524   if (env()->jvmti_can_post_on_exceptions()) {
 525     // check if we must post exception events, take uncommon trap if so
 526     uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
 527     // here if should_post_on_exceptions is false
 528     // continue on with the normal codegen
 529   }
 530 
 531   // If this particular condition has not yet happened at this
 532   // bytecode, then use the uncommon trap mechanism, and allow for
 533   // a future recompilation if several traps occur here.
 534   // If the throw is hot, try to use a more complicated inline mechanism
 535   // which keeps execution inside the compiled code.
 536   bool treat_throw_as_hot = false;
 537   ciMethodData* md = method()->method_data();
 538 
 539   if (ProfileTraps) {
 540     if (too_many_traps(reason)) {
 541       treat_throw_as_hot = true;
 542     }
 543     // (If there is no MDO at all, assume it is early in
 544     // execution, and that any deopts are part of the
 545     // startup transient, and don't need to be remembered.)
 546 
 547     // Also, if there is a local exception handler, treat all throws
 548     // as hot if there has been at least one in this method.
 549     if (C->trap_count(reason) != 0
 550         && method()->method_data()->trap_count(reason) != 0
 551         && has_ex_handler()) {
 552         treat_throw_as_hot = true;
 553     }
 554   }
 555 
 556   // If this throw happens frequently, an uncommon trap might cause
 557   // a performance pothole.  If there is a local exception handler,
 558   // and if this particular bytecode appears to be deoptimizing often,
 559   // let us handle the throw inline, with a preconstructed instance.
 560   // Note:   If the deopt count has blown up, the uncommon trap
 561   // runtime is going to flush this nmethod, not matter what.
 562   if (treat_throw_as_hot
 563       && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) {
 564     // If the throw is local, we use a pre-existing instance and
 565     // punt on the backtrace.  This would lead to a missing backtrace
 566     // (a repeat of 4292742) if the backtrace object is ever asked
 567     // for its backtrace.
 568     // Fixing this remaining case of 4292742 requires some flavor of
 569     // escape analysis.  Leave that for the future.
 570     ciInstance* ex_obj = NULL;
 571     switch (reason) {
 572     case Deoptimization::Reason_null_check:
 573       ex_obj = env()->NullPointerException_instance();
 574       break;
 575     case Deoptimization::Reason_div0_check:
 576       ex_obj = env()->ArithmeticException_instance();
 577       break;
 578     case Deoptimization::Reason_range_check:
 579       ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
 580       break;
 581     case Deoptimization::Reason_class_check:
 582       if (java_bc() == Bytecodes::_aastore) {
 583         ex_obj = env()->ArrayStoreException_instance();
 584       } else {
 585         ex_obj = env()->ClassCastException_instance();
 586       }
 587       break;
 588     }
 589     if (failing()) { stop(); return; }  // exception allocation might fail
 590     if (ex_obj != NULL) {
 591       // Cheat with a preallocated exception object.
 592       if (C->log() != NULL)
 593         C->log()->elem("hot_throw preallocated='1' reason='%s'",
 594                        Deoptimization::trap_reason_name(reason));
 595       const TypeInstPtr* ex_con  = TypeInstPtr::make(ex_obj);
 596       Node*              ex_node = _gvn.transform(ConNode::make(ex_con));
 597 
 598       // Clear the detail message of the preallocated exception object.
 599       // Weblogic sometimes mutates the detail message of exceptions
 600       // using reflection.
 601       int offset = java_lang_Throwable::get_detailMessage_offset();
 602       const TypePtr* adr_typ = ex_con->add_offset(offset);
 603 
 604       Node *adr = basic_plus_adr(ex_node, ex_node, offset);
 605       const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
 606       // Conservatively release stores of object references.
 607       Node *store = store_oop_to_object(control(), ex_node, adr, adr_typ, null(), val_type, T_OBJECT, MemNode::release);
 608 
 609       add_exception_state(make_exception_state(ex_node));
 610       return;
 611     }
 612   }
 613 
 614   // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
 615   // It won't be much cheaper than bailing to the interp., since we'll
 616   // have to pass up all the debug-info, and the runtime will have to
 617   // create the stack trace.
 618 
 619   // Usual case:  Bail to interpreter.
 620   // Reserve the right to recompile if we haven't seen anything yet.
 621 
 622   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? C->method() : NULL;
 623   Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
 624   if (treat_throw_as_hot
 625       && (method()->method_data()->trap_recompiled_at(bci(), m)
 626           || C->too_many_traps(reason))) {
 627     // We cannot afford to take more traps here.  Suffer in the interpreter.
 628     if (C->log() != NULL)
 629       C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
 630                      Deoptimization::trap_reason_name(reason),
 631                      C->trap_count(reason));
 632     action = Deoptimization::Action_none;
 633   }
 634 
 635   // "must_throw" prunes the JVM state to include only the stack, if there
 636   // are no local exception handlers.  This should cut down on register
 637   // allocation time and code size, by drastically reducing the number
 638   // of in-edges on the call to the uncommon trap.
 639 
 640   uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw);
 641 }
 642 
 643 
 644 //----------------------------PreserveJVMState---------------------------------
 645 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
 646   debug_only(kit->verify_map());
 647   _kit    = kit;
 648   _map    = kit->map();   // preserve the map
 649   _sp     = kit->sp();
 650   kit->set_map(clone_map ? kit->clone_map() : NULL);
 651 #ifdef ASSERT
 652   _bci    = kit->bci();
 653   Parse* parser = kit->is_Parse();
 654   int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
 655   _block  = block;
 656 #endif
 657 }
 658 PreserveJVMState::~PreserveJVMState() {
 659   GraphKit* kit = _kit;
 660 #ifdef ASSERT
 661   assert(kit->bci() == _bci, "bci must not shift");
 662   Parse* parser = kit->is_Parse();
 663   int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
 664   assert(block == _block,    "block must not shift");
 665 #endif
 666   kit->set_map(_map);
 667   kit->set_sp(_sp);
 668 }
 669 
 670 
 671 //-----------------------------BuildCutout-------------------------------------
 672 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
 673   : PreserveJVMState(kit)
 674 {
 675   assert(p->is_Con() || p->is_Bool(), "test must be a bool");
 676   SafePointNode* outer_map = _map;   // preserved map is caller's
 677   SafePointNode* inner_map = kit->map();
 678   IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
 679   outer_map->set_control(kit->gvn().transform( new IfTrueNode(iff) ));
 680   inner_map->set_control(kit->gvn().transform( new IfFalseNode(iff) ));
 681 }
 682 BuildCutout::~BuildCutout() {
 683   GraphKit* kit = _kit;
 684   assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
 685 }
 686 
 687 //---------------------------PreserveReexecuteState----------------------------
 688 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
 689   assert(!kit->stopped(), "must call stopped() before");
 690   _kit    =    kit;
 691   _sp     =    kit->sp();
 692   _reexecute = kit->jvms()->_reexecute;
 693 }
 694 PreserveReexecuteState::~PreserveReexecuteState() {
 695   if (_kit->stopped()) return;
 696   _kit->jvms()->_reexecute = _reexecute;
 697   _kit->set_sp(_sp);
 698 }
 699 
 700 //------------------------------clone_map--------------------------------------
 701 // Implementation of PreserveJVMState
 702 //
 703 // Only clone_map(...) here. If this function is only used in the
 704 // PreserveJVMState class we may want to get rid of this extra
 705 // function eventually and do it all there.
 706 
 707 SafePointNode* GraphKit::clone_map() {
 708   if (map() == NULL)  return NULL;
 709 
 710   // Clone the memory edge first
 711   Node* mem = MergeMemNode::make(map()->memory());
 712   gvn().set_type_bottom(mem);
 713 
 714   SafePointNode *clonemap = (SafePointNode*)map()->clone();
 715   JVMState* jvms = this->jvms();
 716   JVMState* clonejvms = jvms->clone_shallow(C);
 717   clonemap->set_memory(mem);
 718   clonemap->set_jvms(clonejvms);
 719   clonejvms->set_map(clonemap);
 720   record_for_igvn(clonemap);
 721   gvn().set_type_bottom(clonemap);
 722   return clonemap;
 723 }
 724 
 725 
 726 //-----------------------------set_map_clone-----------------------------------
 727 void GraphKit::set_map_clone(SafePointNode* m) {
 728   _map = m;
 729   _map = clone_map();
 730   _map->set_next_exception(NULL);
 731   debug_only(verify_map());
 732 }
 733 
 734 
 735 //----------------------------kill_dead_locals---------------------------------
 736 // Detect any locals which are known to be dead, and force them to top.
 737 void GraphKit::kill_dead_locals() {
 738   // Consult the liveness information for the locals.  If any
 739   // of them are unused, then they can be replaced by top().  This
 740   // should help register allocation time and cut down on the size
 741   // of the deoptimization information.
 742 
 743   // This call is made from many of the bytecode handling
 744   // subroutines called from the Big Switch in do_one_bytecode.
 745   // Every bytecode which might include a slow path is responsible
 746   // for killing its dead locals.  The more consistent we
 747   // are about killing deads, the fewer useless phis will be
 748   // constructed for them at various merge points.
 749 
 750   // bci can be -1 (InvocationEntryBci).  We return the entry
 751   // liveness for the method.
 752 
 753   if (method() == NULL || method()->code_size() == 0) {
 754     // We are building a graph for a call to a native method.
 755     // All locals are live.
 756     return;
 757   }
 758 
 759   ResourceMark rm;
 760 
 761   // Consult the liveness information for the locals.  If any
 762   // of them are unused, then they can be replaced by top().  This
 763   // should help register allocation time and cut down on the size
 764   // of the deoptimization information.
 765   MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
 766 
 767   int len = (int)live_locals.size();
 768   assert(len <= jvms()->loc_size(), "too many live locals");
 769   for (int local = 0; local < len; local++) {
 770     if (!live_locals.at(local)) {
 771       set_local(local, top());
 772     }
 773   }
 774 }
 775 
 776 #ifdef ASSERT
 777 //-------------------------dead_locals_are_killed------------------------------
 778 // Return true if all dead locals are set to top in the map.
 779 // Used to assert "clean" debug info at various points.
 780 bool GraphKit::dead_locals_are_killed() {
 781   if (method() == NULL || method()->code_size() == 0) {
 782     // No locals need to be dead, so all is as it should be.
 783     return true;
 784   }
 785 
 786   // Make sure somebody called kill_dead_locals upstream.
 787   ResourceMark rm;
 788   for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
 789     if (jvms->loc_size() == 0)  continue;  // no locals to consult
 790     SafePointNode* map = jvms->map();
 791     ciMethod* method = jvms->method();
 792     int       bci    = jvms->bci();
 793     if (jvms == this->jvms()) {
 794       bci = this->bci();  // it might not yet be synched
 795     }
 796     MethodLivenessResult live_locals = method->liveness_at_bci(bci);
 797     int len = (int)live_locals.size();
 798     if (!live_locals.is_valid() || len == 0)
 799       // This method is trivial, or is poisoned by a breakpoint.
 800       return true;
 801     assert(len == jvms->loc_size(), "live map consistent with locals map");
 802     for (int local = 0; local < len; local++) {
 803       if (!live_locals.at(local) && map->local(jvms, local) != top()) {
 804         if (PrintMiscellaneous && (Verbose || WizardMode)) {
 805           tty->print_cr("Zombie local %d: ", local);
 806           jvms->dump();
 807         }
 808         return false;
 809       }
 810     }
 811   }
 812   return true;
 813 }
 814 
 815 #endif //ASSERT
 816 
 817 // Helper function for enforcing certain bytecodes to reexecute if
 818 // deoptimization happens
 819 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
 820   ciMethod* cur_method = jvms->method();
 821   int       cur_bci   = jvms->bci();
 822   if (cur_method != NULL && cur_bci != InvocationEntryBci) {
 823     Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
 824     return Interpreter::bytecode_should_reexecute(code) ||
 825            is_anewarray && code == Bytecodes::_multianewarray;
 826     // Reexecute _multianewarray bytecode which was replaced with
 827     // sequence of [a]newarray. See Parse::do_multianewarray().
 828     //
 829     // Note: interpreter should not have it set since this optimization
 830     // is limited by dimensions and guarded by flag so in some cases
 831     // multianewarray() runtime calls will be generated and
 832     // the bytecode should not be reexecutes (stack will not be reset).
 833   } else
 834     return false;
 835 }
 836 
 837 // Helper function for adding JVMState and debug information to node
 838 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
 839   // Add the safepoint edges to the call (or other safepoint).
 840 
 841   // Make sure dead locals are set to top.  This
 842   // should help register allocation time and cut down on the size
 843   // of the deoptimization information.
 844   assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
 845 
 846   // Walk the inline list to fill in the correct set of JVMState's
 847   // Also fill in the associated edges for each JVMState.
 848 
 849   // If the bytecode needs to be reexecuted we need to put
 850   // the arguments back on the stack.
 851   const bool should_reexecute = jvms()->should_reexecute();
 852   JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
 853 
 854   // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
 855   // undefined if the bci is different.  This is normal for Parse but it
 856   // should not happen for LibraryCallKit because only one bci is processed.
 857   assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
 858          "in LibraryCallKit the reexecute bit should not change");
 859 
 860   // If we are guaranteed to throw, we can prune everything but the
 861   // input to the current bytecode.
 862   bool can_prune_locals = false;
 863   uint stack_slots_not_pruned = 0;
 864   int inputs = 0, depth = 0;
 865   if (must_throw) {
 866     assert(method() == youngest_jvms->method(), "sanity");
 867     if (compute_stack_effects(inputs, depth)) {
 868       can_prune_locals = true;
 869       stack_slots_not_pruned = inputs;
 870     }
 871   }
 872 
 873   if (env()->should_retain_local_variables()) {
 874     // At any safepoint, this method can get breakpointed, which would
 875     // then require an immediate deoptimization.
 876     can_prune_locals = false;  // do not prune locals
 877     stack_slots_not_pruned = 0;
 878   }
 879 
 880   // do not scribble on the input jvms
 881   JVMState* out_jvms = youngest_jvms->clone_deep(C);
 882   call->set_jvms(out_jvms); // Start jvms list for call node
 883 
 884   // For a known set of bytecodes, the interpreter should reexecute them if
 885   // deoptimization happens. We set the reexecute state for them here
 886   if (out_jvms->is_reexecute_undefined() && //don't change if already specified
 887       should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
 888     out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
 889   }
 890 
 891   // Presize the call:
 892   DEBUG_ONLY(uint non_debug_edges = call->req());
 893   call->add_req_batch(top(), youngest_jvms->debug_depth());
 894   assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
 895 
 896   // Set up edges so that the call looks like this:
 897   //  Call [state:] ctl io mem fptr retadr
 898   //       [parms:] parm0 ... parmN
 899   //       [root:]  loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 900   //    [...mid:]   loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
 901   //       [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 902   // Note that caller debug info precedes callee debug info.
 903 
 904   // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
 905   uint debug_ptr = call->req();
 906 
 907   // Loop over the map input edges associated with jvms, add them
 908   // to the call node, & reset all offsets to match call node array.
 909   for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) {
 910     uint debug_end   = debug_ptr;
 911     uint debug_start = debug_ptr - in_jvms->debug_size();
 912     debug_ptr = debug_start;  // back up the ptr
 913 
 914     uint p = debug_start;  // walks forward in [debug_start, debug_end)
 915     uint j, k, l;
 916     SafePointNode* in_map = in_jvms->map();
 917     out_jvms->set_map(call);
 918 
 919     if (can_prune_locals) {
 920       assert(in_jvms->method() == out_jvms->method(), "sanity");
 921       // If the current throw can reach an exception handler in this JVMS,
 922       // then we must keep everything live that can reach that handler.
 923       // As a quick and dirty approximation, we look for any handlers at all.
 924       if (in_jvms->method()->has_exception_handlers()) {
 925         can_prune_locals = false;
 926       }
 927     }
 928 
 929     // Add the Locals
 930     k = in_jvms->locoff();
 931     l = in_jvms->loc_size();
 932     out_jvms->set_locoff(p);
 933     if (!can_prune_locals) {
 934       for (j = 0; j < l; j++)
 935         call->set_req(p++, in_map->in(k+j));
 936     } else {
 937       p += l;  // already set to top above by add_req_batch
 938     }
 939 
 940     // Add the Expression Stack
 941     k = in_jvms->stkoff();
 942     l = in_jvms->sp();
 943     out_jvms->set_stkoff(p);
 944     if (!can_prune_locals) {
 945       for (j = 0; j < l; j++)
 946         call->set_req(p++, in_map->in(k+j));
 947     } else if (can_prune_locals && stack_slots_not_pruned != 0) {
 948       // Divide stack into {S0,...,S1}, where S0 is set to top.
 949       uint s1 = stack_slots_not_pruned;
 950       stack_slots_not_pruned = 0;  // for next iteration
 951       if (s1 > l)  s1 = l;
 952       uint s0 = l - s1;
 953       p += s0;  // skip the tops preinstalled by add_req_batch
 954       for (j = s0; j < l; j++)
 955         call->set_req(p++, in_map->in(k+j));
 956     } else {
 957       p += l;  // already set to top above by add_req_batch
 958     }
 959 
 960     // Add the Monitors
 961     k = in_jvms->monoff();
 962     l = in_jvms->mon_size();
 963     out_jvms->set_monoff(p);
 964     for (j = 0; j < l; j++)
 965       call->set_req(p++, in_map->in(k+j));
 966 
 967     // Copy any scalar object fields.
 968     k = in_jvms->scloff();
 969     l = in_jvms->scl_size();
 970     out_jvms->set_scloff(p);
 971     for (j = 0; j < l; j++)
 972       call->set_req(p++, in_map->in(k+j));
 973 
 974     // Finish the new jvms.
 975     out_jvms->set_endoff(p);
 976 
 977     assert(out_jvms->endoff()     == debug_end,             "fill ptr must match");
 978     assert(out_jvms->depth()      == in_jvms->depth(),      "depth must match");
 979     assert(out_jvms->loc_size()   == in_jvms->loc_size(),   "size must match");
 980     assert(out_jvms->mon_size()   == in_jvms->mon_size(),   "size must match");
 981     assert(out_jvms->scl_size()   == in_jvms->scl_size(),   "size must match");
 982     assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
 983 
 984     // Update the two tail pointers in parallel.
 985     out_jvms = out_jvms->caller();
 986     in_jvms  = in_jvms->caller();
 987   }
 988 
 989   assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
 990 
 991   // Test the correctness of JVMState::debug_xxx accessors:
 992   assert(call->jvms()->debug_start() == non_debug_edges, "");
 993   assert(call->jvms()->debug_end()   == call->req(), "");
 994   assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
 995 }
 996 
 997 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
 998   Bytecodes::Code code = java_bc();
 999   if (code == Bytecodes::_wide) {
1000     code = method()->java_code_at_bci(bci() + 1);
1001   }
1002 
1003   BasicType rtype = T_ILLEGAL;
1004   int       rsize = 0;
1005 
1006   if (code != Bytecodes::_illegal) {
1007     depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1008     rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1009     if (rtype < T_CONFLICT)
1010       rsize = type2size[rtype];
1011   }
1012 
1013   switch (code) {
1014   case Bytecodes::_illegal:
1015     return false;
1016 
1017   case Bytecodes::_ldc:
1018   case Bytecodes::_ldc_w:
1019   case Bytecodes::_ldc2_w:
1020     inputs = 0;
1021     break;
1022 
1023   case Bytecodes::_dup:         inputs = 1;  break;
1024   case Bytecodes::_dup_x1:      inputs = 2;  break;
1025   case Bytecodes::_dup_x2:      inputs = 3;  break;
1026   case Bytecodes::_dup2:        inputs = 2;  break;
1027   case Bytecodes::_dup2_x1:     inputs = 3;  break;
1028   case Bytecodes::_dup2_x2:     inputs = 4;  break;
1029   case Bytecodes::_swap:        inputs = 2;  break;
1030   case Bytecodes::_arraylength: inputs = 1;  break;
1031 
1032   case Bytecodes::_getstatic:
1033   case Bytecodes::_putstatic:
1034   case Bytecodes::_getfield:
1035   case Bytecodes::_vgetfield:
1036   case Bytecodes::_putfield:
1037     {
1038       bool ignored_will_link;
1039       ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1040       int      size  = field->type()->size();
1041       bool is_get = (depth >= 0), is_static = (depth & 1);
1042       inputs = (is_static ? 0 : 1);
1043       if (is_get) {
1044         depth = size - inputs;
1045       } else {
1046         inputs += size;        // putxxx pops the value from the stack
1047         depth = - inputs;
1048       }
1049     }
1050     break;
1051 
1052   case Bytecodes::_invokevirtual:
1053   case Bytecodes::_invokedirect:
1054   case Bytecodes::_invokespecial:
1055   case Bytecodes::_invokestatic:
1056   case Bytecodes::_invokedynamic:
1057   case Bytecodes::_invokeinterface:
1058     {
1059       bool ignored_will_link;
1060       ciSignature* declared_signature = NULL;
1061       ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1062       assert(declared_signature != NULL, "cannot be null");
1063       inputs   = declared_signature->arg_size_for_bc(code);
1064       int size = declared_signature->return_type()->size();
1065       depth = size - inputs;
1066     }
1067     break;
1068 
1069   case Bytecodes::_multianewarray:
1070     {
1071       ciBytecodeStream iter(method());
1072       iter.reset_to_bci(bci());
1073       iter.next();
1074       inputs = iter.get_dimensions();
1075       assert(rsize == 1, "");
1076       depth = rsize - inputs;
1077     }
1078     break;
1079 
1080   case Bytecodes::_vnew: {
1081     // vnew pops the values from the stack
1082     ciValueKlass* vk = method()->holder()->as_value_klass();
1083     inputs = vk->field_size();
1084     depth = rsize - inputs;
1085     break;
1086   }
1087 
1088   case Bytecodes::_ireturn:
1089   case Bytecodes::_lreturn:
1090   case Bytecodes::_freturn:
1091   case Bytecodes::_dreturn:
1092   case Bytecodes::_areturn:
1093   case Bytecodes::_vreturn:
1094     assert(rsize = -depth, "");
1095     inputs = rsize;
1096     break;
1097 
1098   case Bytecodes::_jsr:
1099   case Bytecodes::_jsr_w:
1100     inputs = 0;
1101     depth  = 1;                  // S.B. depth=1, not zero
1102     break;
1103 
1104   default:
1105     // bytecode produces a typed result
1106     inputs = rsize - depth;
1107     assert(inputs >= 0, "");
1108     break;
1109   }
1110 
1111 #ifdef ASSERT
1112   // spot check
1113   int outputs = depth + inputs;
1114   assert(outputs >= 0, "sanity");
1115   switch (code) {
1116   case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1117   case Bytecodes::_athrow:    assert(inputs == 1 && outputs == 0, ""); break;
1118   case Bytecodes::_aload_0:   assert(inputs == 0 && outputs == 1, ""); break;
1119   case Bytecodes::_return:    assert(inputs == 0 && outputs == 0, ""); break;
1120   case Bytecodes::_drem:      assert(inputs == 4 && outputs == 2, ""); break;
1121   }
1122 #endif //ASSERT
1123 
1124   return true;
1125 }
1126 
1127 
1128 
1129 //------------------------------basic_plus_adr---------------------------------
1130 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1131   // short-circuit a common case
1132   if (offset == intcon(0))  return ptr;
1133   return _gvn.transform( new AddPNode(base, ptr, offset) );
1134 }
1135 
1136 Node* GraphKit::ConvI2L(Node* offset) {
1137   // short-circuit a common case
1138   jint offset_con = find_int_con(offset, Type::OffsetBot);
1139   if (offset_con != Type::OffsetBot) {
1140     return longcon((jlong) offset_con);
1141   }
1142   return _gvn.transform( new ConvI2LNode(offset));
1143 }
1144 
1145 Node* GraphKit::ConvI2UL(Node* offset) {
1146   juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1147   if (offset_con != (juint) Type::OffsetBot) {
1148     return longcon((julong) offset_con);
1149   }
1150   Node* conv = _gvn.transform( new ConvI2LNode(offset));
1151   Node* mask = _gvn.transform(ConLNode::make((julong) max_juint));
1152   return _gvn.transform( new AndLNode(conv, mask) );
1153 }
1154 
1155 Node* GraphKit::ConvL2I(Node* offset) {
1156   // short-circuit a common case
1157   jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1158   if (offset_con != (jlong)Type::OffsetBot) {
1159     return intcon((int) offset_con);
1160   }
1161   return _gvn.transform( new ConvL2INode(offset));
1162 }
1163 
1164 //-------------------------load_object_klass-----------------------------------
1165 Node* GraphKit::load_object_klass(Node* obj) {
1166   // Special-case a fresh allocation to avoid building nodes:
1167   Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1168   if (akls != NULL)  return akls;
1169   Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1170   return _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), k_adr, TypeInstPtr::KLASS));
1171 }
1172 
1173 //-------------------------load_array_length-----------------------------------
1174 Node* GraphKit::load_array_length(Node* array) {
1175   // Special-case a fresh allocation to avoid building nodes:
1176   AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn);
1177   Node *alen;
1178   if (alloc == NULL) {
1179     Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1180     alen = _gvn.transform( new LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1181   } else {
1182     alen = alloc->Ideal_length();
1183     Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn);
1184     if (ccast != alen) {
1185       alen = _gvn.transform(ccast);
1186     }
1187   }
1188   return alen;
1189 }
1190 
1191 //------------------------------do_null_check----------------------------------
1192 // Helper function to do a NULL pointer check.  Returned value is
1193 // the incoming address with NULL casted away.  You are allowed to use the
1194 // not-null value only if you are control dependent on the test.
1195 #ifndef PRODUCT
1196 extern int explicit_null_checks_inserted,
1197            explicit_null_checks_elided;
1198 #endif
1199 Node* GraphKit::null_check_common(Node* value, BasicType type,
1200                                   // optional arguments for variations:
1201                                   bool assert_null,
1202                                   Node* *null_control,
1203                                   bool speculative) {
1204   assert(!assert_null || null_control == NULL, "not both at once");
1205   if (stopped())  return top();
1206   if (!GenerateCompilerNullChecks && !assert_null && null_control == NULL) {
1207     // For some performance testing, we may wish to suppress null checking.
1208     value = cast_not_null(value);   // Make it appear to be non-null (4962416).
1209     return value;
1210   }
1211   NOT_PRODUCT(explicit_null_checks_inserted++);
1212 
1213   // Construct NULL check
1214   Node *chk = NULL;
1215   switch(type) {
1216     case T_LONG   : chk = new CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1217     case T_INT    : chk = new CmpINode(value, _gvn.intcon(0)); break;
1218     case T_ARRAY  : // fall through
1219       type = T_OBJECT;  // simplify further tests
1220     case T_OBJECT : {
1221       const Type *t = _gvn.type( value );
1222 
1223       const TypeOopPtr* tp = t->isa_oopptr();
1224       if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded()
1225           // Only for do_null_check, not any of its siblings:
1226           && !assert_null && null_control == NULL) {
1227         // Usually, any field access or invocation on an unloaded oop type
1228         // will simply fail to link, since the statically linked class is
1229         // likely also to be unloaded.  However, in -Xcomp mode, sometimes
1230         // the static class is loaded but the sharper oop type is not.
1231         // Rather than checking for this obscure case in lots of places,
1232         // we simply observe that a null check on an unloaded class
1233         // will always be followed by a nonsense operation, so we
1234         // can just issue the uncommon trap here.
1235         // Our access to the unloaded class will only be correct
1236         // after it has been loaded and initialized, which requires
1237         // a trip through the interpreter.
1238 #ifndef PRODUCT
1239         if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); }
1240 #endif
1241         uncommon_trap(Deoptimization::Reason_unloaded,
1242                       Deoptimization::Action_reinterpret,
1243                       tp->klass(), "!loaded");
1244         return top();
1245       }
1246 
1247       if (assert_null) {
1248         // See if the type is contained in NULL_PTR.
1249         // If so, then the value is already null.
1250         if (t->higher_equal(TypePtr::NULL_PTR)) {
1251           NOT_PRODUCT(explicit_null_checks_elided++);
1252           return value;           // Elided null assert quickly!
1253         }
1254       } else {
1255         // See if mixing in the NULL pointer changes type.
1256         // If so, then the NULL pointer was not allowed in the original
1257         // type.  In other words, "value" was not-null.
1258         if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1259           // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1260           NOT_PRODUCT(explicit_null_checks_elided++);
1261           return value;           // Elided null check quickly!
1262         }
1263       }
1264       chk = new CmpPNode( value, null() );
1265       break;
1266     }
1267 
1268     default:
1269       fatal("unexpected type: %s", type2name(type));
1270   }
1271   assert(chk != NULL, "sanity check");
1272   chk = _gvn.transform(chk);
1273 
1274   BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1275   BoolNode *btst = new BoolNode( chk, btest);
1276   Node   *tst = _gvn.transform( btst );
1277 
1278   //-----------
1279   // if peephole optimizations occurred, a prior test existed.
1280   // If a prior test existed, maybe it dominates as we can avoid this test.
1281   if (tst != btst && type == T_OBJECT) {
1282     // At this point we want to scan up the CFG to see if we can
1283     // find an identical test (and so avoid this test altogether).
1284     Node *cfg = control();
1285     int depth = 0;
1286     while( depth < 16 ) {       // Limit search depth for speed
1287       if( cfg->Opcode() == Op_IfTrue &&
1288           cfg->in(0)->in(1) == tst ) {
1289         // Found prior test.  Use "cast_not_null" to construct an identical
1290         // CastPP (and hence hash to) as already exists for the prior test.
1291         // Return that casted value.
1292         if (assert_null) {
1293           replace_in_map(value, null());
1294           return null();  // do not issue the redundant test
1295         }
1296         Node *oldcontrol = control();
1297         set_control(cfg);
1298         Node *res = cast_not_null(value);
1299         set_control(oldcontrol);
1300         NOT_PRODUCT(explicit_null_checks_elided++);
1301         return res;
1302       }
1303       cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1304       if (cfg == NULL)  break;  // Quit at region nodes
1305       depth++;
1306     }
1307   }
1308 
1309   //-----------
1310   // Branch to failure if null
1311   float ok_prob = PROB_MAX;  // a priori estimate:  nulls never happen
1312   Deoptimization::DeoptReason reason;
1313   if (assert_null) {
1314     reason = Deoptimization::Reason_null_assert;
1315   } else if (type == T_OBJECT) {
1316     reason = Deoptimization::reason_null_check(speculative);
1317   } else {
1318     reason = Deoptimization::Reason_div0_check;
1319   }
1320   // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1321   // ciMethodData::has_trap_at will return a conservative -1 if any
1322   // must-be-null assertion has failed.  This could cause performance
1323   // problems for a method after its first do_null_assert failure.
1324   // Consider using 'Reason_class_check' instead?
1325 
1326   // To cause an implicit null check, we set the not-null probability
1327   // to the maximum (PROB_MAX).  For an explicit check the probability
1328   // is set to a smaller value.
1329   if (null_control != NULL || too_many_traps(reason)) {
1330     // probability is less likely
1331     ok_prob =  PROB_LIKELY_MAG(3);
1332   } else if (!assert_null &&
1333              (ImplicitNullCheckThreshold > 0) &&
1334              method() != NULL &&
1335              (method()->method_data()->trap_count(reason)
1336               >= (uint)ImplicitNullCheckThreshold)) {
1337     ok_prob =  PROB_LIKELY_MAG(3);
1338   }
1339 
1340   if (null_control != NULL) {
1341     IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1342     Node* null_true = _gvn.transform( new IfFalseNode(iff));
1343     set_control(      _gvn.transform( new IfTrueNode(iff)));
1344 #ifndef PRODUCT
1345     if (null_true == top()) {
1346       explicit_null_checks_elided++;
1347     }
1348 #endif
1349     (*null_control) = null_true;
1350   } else {
1351     BuildCutout unless(this, tst, ok_prob);
1352     // Check for optimizer eliding test at parse time
1353     if (stopped()) {
1354       // Failure not possible; do not bother making uncommon trap.
1355       NOT_PRODUCT(explicit_null_checks_elided++);
1356     } else if (assert_null) {
1357       uncommon_trap(reason,
1358                     Deoptimization::Action_make_not_entrant,
1359                     NULL, "assert_null");
1360     } else {
1361       replace_in_map(value, zerocon(type));
1362       builtin_throw(reason);
1363     }
1364   }
1365 
1366   // Must throw exception, fall-thru not possible?
1367   if (stopped()) {
1368     return top();               // No result
1369   }
1370 
1371   if (assert_null) {
1372     // Cast obj to null on this path.
1373     replace_in_map(value, zerocon(type));
1374     return zerocon(type);
1375   }
1376 
1377   // Cast obj to not-null on this path, if there is no null_control.
1378   // (If there is a null_control, a non-null value may come back to haunt us.)
1379   if (type == T_OBJECT) {
1380     Node* cast = cast_not_null(value, false);
1381     if (null_control == NULL || (*null_control) == top())
1382       replace_in_map(value, cast);
1383     value = cast;
1384   }
1385 
1386   return value;
1387 }
1388 
1389 
1390 //------------------------------cast_not_null----------------------------------
1391 // Cast obj to not-null on this path
1392 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1393   const Type *t = _gvn.type(obj);
1394   const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1395   // Object is already not-null?
1396   if( t == t_not_null ) return obj;
1397 
1398   Node *cast = new CastPPNode(obj,t_not_null);
1399   cast->init_req(0, control());
1400   cast = _gvn.transform( cast );
1401 
1402   // Scan for instances of 'obj' in the current JVM mapping.
1403   // These instances are known to be not-null after the test.
1404   if (do_replace_in_map)
1405     replace_in_map(obj, cast);
1406 
1407   return cast;                  // Return casted value
1408 }
1409 
1410 
1411 //--------------------------replace_in_map-------------------------------------
1412 void GraphKit::replace_in_map(Node* old, Node* neww) {
1413   if (old == neww) {
1414     return;
1415   }
1416 
1417   map()->replace_edge(old, neww);
1418 
1419   // Note: This operation potentially replaces any edge
1420   // on the map.  This includes locals, stack, and monitors
1421   // of the current (innermost) JVM state.
1422 
1423   // don't let inconsistent types from profiling escape this
1424   // method
1425 
1426   const Type* told = _gvn.type(old);
1427   const Type* tnew = _gvn.type(neww);
1428 
1429   if (!tnew->higher_equal(told)) {
1430     return;
1431   }
1432 
1433   map()->record_replaced_node(old, neww);
1434 }
1435 
1436 
1437 //=============================================================================
1438 //--------------------------------memory---------------------------------------
1439 Node* GraphKit::memory(uint alias_idx) {
1440   MergeMemNode* mem = merged_memory();
1441   Node* p = mem->memory_at(alias_idx);
1442   _gvn.set_type(p, Type::MEMORY);  // must be mapped
1443   return p;
1444 }
1445 
1446 //-----------------------------reset_memory------------------------------------
1447 Node* GraphKit::reset_memory() {
1448   Node* mem = map()->memory();
1449   // do not use this node for any more parsing!
1450   debug_only( map()->set_memory((Node*)NULL) );
1451   return _gvn.transform( mem );
1452 }
1453 
1454 //------------------------------set_all_memory---------------------------------
1455 void GraphKit::set_all_memory(Node* newmem) {
1456   Node* mergemem = MergeMemNode::make(newmem);
1457   gvn().set_type_bottom(mergemem);
1458   map()->set_memory(mergemem);
1459 }
1460 
1461 //------------------------------set_all_memory_call----------------------------
1462 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1463   Node* newmem = _gvn.transform( new ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1464   set_all_memory(newmem);
1465 }
1466 
1467 //=============================================================================
1468 //
1469 // parser factory methods for MemNodes
1470 //
1471 // These are layered on top of the factory methods in LoadNode and StoreNode,
1472 // and integrate with the parser's memory state and _gvn engine.
1473 //
1474 
1475 // factory methods in "int adr_idx"
1476 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1477                           int adr_idx,
1478                           MemNode::MemOrd mo,
1479                           LoadNode::ControlDependency control_dependency,
1480                           bool require_atomic_access,
1481                           bool unaligned,
1482                           bool mismatched) {
1483   assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1484   const TypePtr* adr_type = NULL; // debug-mode-only argument
1485   debug_only(adr_type = C->get_adr_type(adr_idx));
1486   Node* mem = memory(adr_idx);
1487   Node* ld;
1488   if (require_atomic_access && bt == T_LONG) {
1489     ld = LoadLNode::make_atomic(ctl, mem, adr, adr_type, t, mo, control_dependency, unaligned, mismatched);
1490   } else if (require_atomic_access && bt == T_DOUBLE) {
1491     ld = LoadDNode::make_atomic(ctl, mem, adr, adr_type, t, mo, control_dependency, unaligned, mismatched);
1492   } else {
1493     ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, unaligned, mismatched);
1494   }
1495   ld = _gvn.transform(ld);
1496 
1497   if (bt == T_VALUETYPE) {
1498     // Load value type from oop
1499     ld = ValueTypeNode::make(gvn(), map()->memory(), ld);
1500   } else if ((bt == T_OBJECT) && C->do_escape_analysis() || C->eliminate_boxing()) {
1501     // Improve graph before escape analysis and boxing elimination.
1502     record_for_igvn(ld);
1503   }
1504   return ld;
1505 }
1506 
1507 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1508                                 int adr_idx,
1509                                 MemNode::MemOrd mo,
1510                                 bool require_atomic_access,
1511                                 bool unaligned,
1512                                 bool mismatched) {
1513   assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1514   const TypePtr* adr_type = NULL;
1515   debug_only(adr_type = C->get_adr_type(adr_idx));
1516   Node *mem = memory(adr_idx);
1517   Node* st;
1518   if (require_atomic_access && bt == T_LONG) {
1519     st = StoreLNode::make_atomic(ctl, mem, adr, adr_type, val, mo);
1520   } else if (require_atomic_access && bt == T_DOUBLE) {
1521     st = StoreDNode::make_atomic(ctl, mem, adr, adr_type, val, mo);
1522   } else {
1523     st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo);
1524   }
1525   if (unaligned) {
1526     st->as_Store()->set_unaligned_access();
1527   }
1528   if (mismatched) {
1529     st->as_Store()->set_mismatched_access();
1530   }
1531   st = _gvn.transform(st);
1532   set_memory(st, adr_idx);
1533   // Back-to-back stores can only remove intermediate store with DU info
1534   // so push on worklist for optimizer.
1535   if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1536     record_for_igvn(st);
1537 
1538   return st;
1539 }
1540 
1541 
1542 void GraphKit::pre_barrier(bool do_load,
1543                            Node* ctl,
1544                            Node* obj,
1545                            Node* adr,
1546                            uint  adr_idx,
1547                            Node* val,
1548                            const TypeOopPtr* val_type,
1549                            Node* pre_val,
1550                            BasicType bt) {
1551 
1552   BarrierSet* bs = Universe::heap()->barrier_set();
1553   set_control(ctl);
1554   switch (bs->kind()) {
1555     case BarrierSet::G1SATBCTLogging:
1556       g1_write_barrier_pre(do_load, obj, adr, adr_idx, val, val_type, pre_val, bt);
1557       break;
1558 
1559     case BarrierSet::CardTableForRS:
1560     case BarrierSet::CardTableExtension:
1561     case BarrierSet::ModRef:
1562       break;
1563 
1564     default      :
1565       ShouldNotReachHere();
1566 
1567   }
1568 }
1569 
1570 bool GraphKit::can_move_pre_barrier() const {
1571   BarrierSet* bs = Universe::heap()->barrier_set();
1572   switch (bs->kind()) {
1573     case BarrierSet::G1SATBCTLogging:
1574       return true; // Can move it if no safepoint
1575 
1576     case BarrierSet::CardTableForRS:
1577     case BarrierSet::CardTableExtension:
1578     case BarrierSet::ModRef:
1579       return true; // There is no pre-barrier
1580 
1581     default      :
1582       ShouldNotReachHere();
1583   }
1584   return false;
1585 }
1586 
1587 void GraphKit::post_barrier(Node* ctl,
1588                             Node* store,
1589                             Node* obj,
1590                             Node* adr,
1591                             uint  adr_idx,
1592                             Node* val,
1593                             BasicType bt,
1594                             bool use_precise) {
1595   BarrierSet* bs = Universe::heap()->barrier_set();
1596   set_control(ctl);
1597   switch (bs->kind()) {
1598     case BarrierSet::G1SATBCTLogging:
1599       g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise);
1600       break;
1601 
1602     case BarrierSet::CardTableForRS:
1603     case BarrierSet::CardTableExtension:
1604       write_barrier_post(store, obj, adr, adr_idx, val, use_precise);
1605       break;
1606 
1607     case BarrierSet::ModRef:
1608       break;
1609 
1610     default      :
1611       ShouldNotReachHere();
1612 
1613   }
1614 }
1615 
1616 Node* GraphKit::store_oop(Node* ctl,
1617                           Node* obj,
1618                           Node* adr,
1619                           const TypePtr* adr_type,
1620                           Node* val,
1621                           const TypeOopPtr* val_type,
1622                           BasicType bt,
1623                           bool use_precise,
1624                           MemNode::MemOrd mo,
1625                           bool mismatched) {
1626   // Transformation of a value which could be NULL pointer (CastPP #NULL)
1627   // could be delayed during Parse (for example, in adjust_map_after_if()).
1628   // Execute transformation here to avoid barrier generation in such case.
1629   if (_gvn.type(val) == TypePtr::NULL_PTR)
1630     val = _gvn.makecon(TypePtr::NULL_PTR);
1631 
1632   set_control(ctl);
1633   if (stopped()) return top(); // Dead path ?
1634 
1635   assert(bt == T_OBJECT || bt == T_VALUETYPE, "sanity");
1636   assert(val != NULL, "not dead path");
1637   uint adr_idx = C->get_alias_index(adr_type);
1638   assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1639 
1640   if (bt == T_VALUETYPE) {
1641     // Allocate value type and store oop
1642     val = val->as_ValueType()->store_to_memory(this);
1643   }
1644 
1645   pre_barrier(true /* do_load */,
1646               control(), obj, adr, adr_idx, val, val_type,
1647               NULL /* pre_val */,
1648               bt);
1649 
1650   Node* store = store_to_memory(control(), adr, val, bt, adr_idx, mo, mismatched);
1651   post_barrier(control(), store, obj, adr, adr_idx, val, bt, use_precise);
1652   return store;
1653 }
1654 
1655 // Could be an array or object we don't know at compile time (unsafe ref.)
1656 Node* GraphKit::store_oop_to_unknown(Node* ctl,
1657                              Node* obj,   // containing obj
1658                              Node* adr,  // actual adress to store val at
1659                              const TypePtr* adr_type,
1660                              Node* val,
1661                              BasicType bt,
1662                              MemNode::MemOrd mo,
1663                              bool mismatched) {
1664   Compile::AliasType* at = C->alias_type(adr_type);
1665   const TypeOopPtr* val_type = NULL;
1666   if (adr_type->isa_instptr()) {
1667     if (at->field() != NULL) {
1668       // known field.  This code is a copy of the do_put_xxx logic.
1669       ciField* field = at->field();
1670       if (!field->type()->is_loaded()) {
1671         val_type = TypeInstPtr::BOTTOM;
1672       } else {
1673         val_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
1674       }
1675     }
1676   } else if (adr_type->isa_aryptr()) {
1677     val_type = adr_type->is_aryptr()->elem()->make_oopptr();
1678   }
1679   if (val_type == NULL) {
1680     val_type = TypeInstPtr::BOTTOM;
1681   }
1682   return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true, mo, mismatched);
1683 }
1684 
1685 
1686 //-------------------------array_element_address-------------------------
1687 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1688                                       const TypeInt* sizetype, Node* ctrl) {
1689   uint shift  = exact_log2(type2aelembytes(elembt));
1690   ciKlass* arytype_klass = _gvn.type(ary)->is_aryptr()->klass();
1691   if (arytype_klass->is_value_array_klass()) {
1692     ciValueArrayKlass* vak = arytype_klass->as_value_array_klass();
1693     shift = vak->log2_element_size();
1694   }
1695   uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1696 
1697   // short-circuit a common case (saves lots of confusing waste motion)
1698   jint idx_con = find_int_con(idx, -1);
1699   if (idx_con >= 0) {
1700     intptr_t offset = header + ((intptr_t)idx_con << shift);
1701     return basic_plus_adr(ary, offset);
1702   }
1703 
1704   // must be correct type for alignment purposes
1705   Node* base  = basic_plus_adr(ary, header);
1706   idx = Compile::conv_I2X_index(&_gvn, idx, sizetype, ctrl);
1707   Node* scale = _gvn.transform( new LShiftXNode(idx, intcon(shift)) );
1708   return basic_plus_adr(ary, base, scale);
1709 }
1710 
1711 //-------------------------load_array_element-------------------------
1712 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) {
1713   const Type* elemtype = arytype->elem();
1714   BasicType elembt = elemtype->array_element_basic_type();
1715   assert(elembt != T_VALUETYPE, "value types are not supported by this method");
1716   Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1717   Node* ld = make_load(ctl, adr, elemtype, elembt, arytype, MemNode::unordered);
1718   return ld;
1719 }
1720 
1721 //-------------------------set_arguments_for_java_call-------------------------
1722 // Arguments (pre-popped from the stack) are taken from the JVMS.
1723 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1724   // Add the call arguments:
1725   uint nargs = call->method()->arg_size();
1726   for (uint i = 0, idx = 0; i < nargs; i++) {
1727     Node* arg = argument(i);
1728     if (ValueTypePassFieldsAsArgs) {
1729       if (arg->is_ValueType()) {
1730         ValueTypeNode* vt = arg->as_ValueType();
1731         // We don't pass value type arguments by reference but instead
1732         // pass each field of the value type
1733         idx += vt->set_arguments_for_java_call(call, idx + TypeFunc::Parms, *this);
1734       } else {
1735         call->init_req(idx + TypeFunc::Parms, arg);
1736         idx++;
1737       }
1738     } else {
1739       if (arg->is_ValueType()) {
1740         // Pass value type argument via oop to callee
1741         arg = arg->as_ValueType()->store_to_memory(this);
1742       }
1743       call->init_req(i + TypeFunc::Parms, arg);
1744     }
1745   }
1746 }
1747 
1748 //---------------------------set_edges_for_java_call---------------------------
1749 // Connect a newly created call into the current JVMS.
1750 // A return value node (if any) is returned from set_edges_for_java_call.
1751 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1752 
1753   // Add the predefined inputs:
1754   call->init_req( TypeFunc::Control, control() );
1755   call->init_req( TypeFunc::I_O    , i_o() );
1756   call->init_req( TypeFunc::Memory , reset_memory() );
1757   call->init_req( TypeFunc::FramePtr, frameptr() );
1758   call->init_req( TypeFunc::ReturnAdr, top() );
1759 
1760   add_safepoint_edges(call, must_throw);
1761 
1762   Node* xcall = _gvn.transform(call);
1763 
1764   if (xcall == top()) {
1765     set_control(top());
1766     return;
1767   }
1768   assert(xcall == call, "call identity is stable");
1769 
1770   // Re-use the current map to produce the result.
1771 
1772   set_control(_gvn.transform(new ProjNode(call, TypeFunc::Control)));
1773   set_i_o(    _gvn.transform(new ProjNode(call, TypeFunc::I_O    , separate_io_proj)));
1774   set_all_memory_call(xcall, separate_io_proj);
1775 
1776   //return xcall;   // no need, caller already has it
1777 }
1778 
1779 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) {
1780   if (stopped())  return top();  // maybe the call folded up?
1781 
1782   // Capture the return value, if any.
1783   Node* ret;
1784   if (call->method() == NULL ||
1785       call->method()->return_type()->basic_type() == T_VOID)
1786         ret = top();
1787   else  ret = _gvn.transform(new ProjNode(call, TypeFunc::Parms));
1788 
1789   // Note:  Since any out-of-line call can produce an exception,
1790   // we always insert an I_O projection from the call into the result.
1791 
1792   make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj);
1793 
1794   if (separate_io_proj) {
1795     // The caller requested separate projections be used by the fall
1796     // through and exceptional paths, so replace the projections for
1797     // the fall through path.
1798     set_i_o(_gvn.transform( new ProjNode(call, TypeFunc::I_O) ));
1799     set_all_memory(_gvn.transform( new ProjNode(call, TypeFunc::Memory) ));
1800   }
1801   return ret;
1802 }
1803 
1804 //--------------------set_predefined_input_for_runtime_call--------------------
1805 // Reading and setting the memory state is way conservative here.
1806 // The real problem is that I am not doing real Type analysis on memory,
1807 // so I cannot distinguish card mark stores from other stores.  Across a GC
1808 // point the Store Barrier and the card mark memory has to agree.  I cannot
1809 // have a card mark store and its barrier split across the GC point from
1810 // either above or below.  Here I get that to happen by reading ALL of memory.
1811 // A better answer would be to separate out card marks from other memory.
1812 // For now, return the input memory state, so that it can be reused
1813 // after the call, if this call has restricted memory effects.
1814 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) {
1815   // Set fixed predefined input arguments
1816   Node* memory = reset_memory();
1817   call->init_req( TypeFunc::Control,   control()  );
1818   call->init_req( TypeFunc::I_O,       top()      ); // does no i/o
1819   call->init_req( TypeFunc::Memory,    memory     ); // may gc ptrs
1820   call->init_req( TypeFunc::FramePtr,  frameptr() );
1821   call->init_req( TypeFunc::ReturnAdr, top()      );
1822   return memory;
1823 }
1824 
1825 //-------------------set_predefined_output_for_runtime_call--------------------
1826 // Set control and memory (not i_o) from the call.
1827 // If keep_mem is not NULL, use it for the output state,
1828 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1829 // If hook_mem is NULL, this call produces no memory effects at all.
1830 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1831 // then only that memory slice is taken from the call.
1832 // In the last case, we must put an appropriate memory barrier before
1833 // the call, so as to create the correct anti-dependencies on loads
1834 // preceding the call.
1835 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1836                                                       Node* keep_mem,
1837                                                       const TypePtr* hook_mem) {
1838   // no i/o
1839   set_control(_gvn.transform( new ProjNode(call,TypeFunc::Control) ));
1840   if (keep_mem) {
1841     // First clone the existing memory state
1842     set_all_memory(keep_mem);
1843     if (hook_mem != NULL) {
1844       // Make memory for the call
1845       Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
1846       // Set the RawPtr memory state only.  This covers all the heap top/GC stuff
1847       // We also use hook_mem to extract specific effects from arraycopy stubs.
1848       set_memory(mem, hook_mem);
1849     }
1850     // ...else the call has NO memory effects.
1851 
1852     // Make sure the call advertises its memory effects precisely.
1853     // This lets us build accurate anti-dependences in gcm.cpp.
1854     assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1855            "call node must be constructed correctly");
1856   } else {
1857     assert(hook_mem == NULL, "");
1858     // This is not a "slow path" call; all memory comes from the call.
1859     set_all_memory_call(call);
1860   }
1861 }
1862 
1863 
1864 // Replace the call with the current state of the kit.
1865 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes) {
1866   JVMState* ejvms = NULL;
1867   if (has_exceptions()) {
1868     ejvms = transfer_exceptions_into_jvms();
1869   }
1870 
1871   ReplacedNodes replaced_nodes = map()->replaced_nodes();
1872   ReplacedNodes replaced_nodes_exception;
1873   Node* ex_ctl = top();
1874 
1875   SafePointNode* final_state = stop();
1876 
1877   // Find all the needed outputs of this call
1878   CallProjections callprojs;
1879   call->extract_projections(&callprojs, true);
1880 
1881   Node* init_mem = call->in(TypeFunc::Memory);
1882   Node* final_mem = final_state->in(TypeFunc::Memory);
1883   Node* final_ctl = final_state->in(TypeFunc::Control);
1884   Node* final_io = final_state->in(TypeFunc::I_O);
1885 
1886   // Replace all the old call edges with the edges from the inlining result
1887   if (callprojs.fallthrough_catchproj != NULL) {
1888     C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
1889   }
1890   if (callprojs.fallthrough_memproj != NULL) {
1891     if (final_mem->is_MergeMem()) {
1892       // Parser's exits MergeMem was not transformed but may be optimized
1893       final_mem = _gvn.transform(final_mem);
1894     }
1895     C->gvn_replace_by(callprojs.fallthrough_memproj,   final_mem);
1896   }
1897   if (callprojs.fallthrough_ioproj != NULL) {
1898     C->gvn_replace_by(callprojs.fallthrough_ioproj,    final_io);
1899   }
1900 
1901   // Replace the result with the new result if it exists and is used
1902   if (callprojs.resproj != NULL && result != NULL) {
1903     C->gvn_replace_by(callprojs.resproj, result);
1904   }
1905 
1906   if (ejvms == NULL) {
1907     // No exception edges to simply kill off those paths
1908     if (callprojs.catchall_catchproj != NULL) {
1909       C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1910     }
1911     if (callprojs.catchall_memproj != NULL) {
1912       C->gvn_replace_by(callprojs.catchall_memproj,   C->top());
1913     }
1914     if (callprojs.catchall_ioproj != NULL) {
1915       C->gvn_replace_by(callprojs.catchall_ioproj,    C->top());
1916     }
1917     // Replace the old exception object with top
1918     if (callprojs.exobj != NULL) {
1919       C->gvn_replace_by(callprojs.exobj, C->top());
1920     }
1921   } else {
1922     GraphKit ekit(ejvms);
1923 
1924     // Load my combined exception state into the kit, with all phis transformed:
1925     SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1926     replaced_nodes_exception = ex_map->replaced_nodes();
1927 
1928     Node* ex_oop = ekit.use_exception_state(ex_map);
1929 
1930     if (callprojs.catchall_catchproj != NULL) {
1931       C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1932       ex_ctl = ekit.control();
1933     }
1934     if (callprojs.catchall_memproj != NULL) {
1935       C->gvn_replace_by(callprojs.catchall_memproj,   ekit.reset_memory());
1936     }
1937     if (callprojs.catchall_ioproj != NULL) {
1938       C->gvn_replace_by(callprojs.catchall_ioproj,    ekit.i_o());
1939     }
1940 
1941     // Replace the old exception object with the newly created one
1942     if (callprojs.exobj != NULL) {
1943       C->gvn_replace_by(callprojs.exobj, ex_oop);
1944     }
1945   }
1946 
1947   // Disconnect the call from the graph
1948   call->disconnect_inputs(NULL, C);
1949   C->gvn_replace_by(call, C->top());
1950 
1951   // Clean up any MergeMems that feed other MergeMems since the
1952   // optimizer doesn't like that.
1953   if (final_mem->is_MergeMem()) {
1954     Node_List wl;
1955     for (SimpleDUIterator i(final_mem); i.has_next(); i.next()) {
1956       Node* m = i.get();
1957       if (m->is_MergeMem() && !wl.contains(m)) {
1958         wl.push(m);
1959       }
1960     }
1961     while (wl.size()  > 0) {
1962       _gvn.transform(wl.pop());
1963     }
1964   }
1965 
1966   if (callprojs.fallthrough_catchproj != NULL && !final_ctl->is_top() && do_replaced_nodes) {
1967     replaced_nodes.apply(C, final_ctl);
1968   }
1969   if (!ex_ctl->is_top() && do_replaced_nodes) {
1970     replaced_nodes_exception.apply(C, ex_ctl);
1971   }
1972 }
1973 
1974 
1975 //------------------------------increment_counter------------------------------
1976 // for statistics: increment a VM counter by 1
1977 
1978 void GraphKit::increment_counter(address counter_addr) {
1979   Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
1980   increment_counter(adr1);
1981 }
1982 
1983 void GraphKit::increment_counter(Node* counter_addr) {
1984   int adr_type = Compile::AliasIdxRaw;
1985   Node* ctrl = control();
1986   Node* cnt  = make_load(ctrl, counter_addr, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
1987   Node* incr = _gvn.transform(new AddINode(cnt, _gvn.intcon(1)));
1988   store_to_memory(ctrl, counter_addr, incr, T_INT, adr_type, MemNode::unordered);
1989 }
1990 
1991 
1992 //------------------------------uncommon_trap----------------------------------
1993 // Bail out to the interpreter in mid-method.  Implemented by calling the
1994 // uncommon_trap blob.  This helper function inserts a runtime call with the
1995 // right debug info.
1996 void GraphKit::uncommon_trap(int trap_request,
1997                              ciKlass* klass, const char* comment,
1998                              bool must_throw,
1999                              bool keep_exact_action) {
2000   if (failing())  stop();
2001   if (stopped())  return; // trap reachable?
2002 
2003   // Note:  If ProfileTraps is true, and if a deopt. actually
2004   // occurs here, the runtime will make sure an MDO exists.  There is
2005   // no need to call method()->ensure_method_data() at this point.
2006 
2007   // Set the stack pointer to the right value for reexecution:
2008   set_sp(reexecute_sp());
2009 
2010 #ifdef ASSERT
2011   if (!must_throw) {
2012     // Make sure the stack has at least enough depth to execute
2013     // the current bytecode.
2014     int inputs, ignored_depth;
2015     if (compute_stack_effects(inputs, ignored_depth)) {
2016       assert(sp() >= inputs, "must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
2017              Bytecodes::name(java_bc()), sp(), inputs);
2018     }
2019   }
2020 #endif
2021 
2022   Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
2023   Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
2024 
2025   switch (action) {
2026   case Deoptimization::Action_maybe_recompile:
2027   case Deoptimization::Action_reinterpret:
2028     // Temporary fix for 6529811 to allow virtual calls to be sure they
2029     // get the chance to go from mono->bi->mega
2030     if (!keep_exact_action &&
2031         Deoptimization::trap_request_index(trap_request) < 0 &&
2032         too_many_recompiles(reason)) {
2033       // This BCI is causing too many recompilations.
2034       if (C->log() != NULL) {
2035         C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'",
2036                 Deoptimization::trap_reason_name(reason),
2037                 Deoptimization::trap_action_name(action));
2038       }
2039       action = Deoptimization::Action_none;
2040       trap_request = Deoptimization::make_trap_request(reason, action);
2041     } else {
2042       C->set_trap_can_recompile(true);
2043     }
2044     break;
2045   case Deoptimization::Action_make_not_entrant:
2046     C->set_trap_can_recompile(true);
2047     break;
2048 #ifdef ASSERT
2049   case Deoptimization::Action_none:
2050   case Deoptimization::Action_make_not_compilable:
2051     break;
2052   default:
2053     fatal("unknown action %d: %s", action, Deoptimization::trap_action_name(action));
2054     break;
2055 #endif
2056   }
2057 
2058   if (TraceOptoParse) {
2059     char buf[100];
2060     tty->print_cr("Uncommon trap %s at bci:%d",
2061                   Deoptimization::format_trap_request(buf, sizeof(buf),
2062                                                       trap_request), bci());
2063   }
2064 
2065   CompileLog* log = C->log();
2066   if (log != NULL) {
2067     int kid = (klass == NULL)? -1: log->identify(klass);
2068     log->begin_elem("uncommon_trap bci='%d'", bci());
2069     char buf[100];
2070     log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2071                                                           trap_request));
2072     if (kid >= 0)         log->print(" klass='%d'", kid);
2073     if (comment != NULL)  log->print(" comment='%s'", comment);
2074     log->end_elem();
2075   }
2076 
2077   // Make sure any guarding test views this path as very unlikely
2078   Node *i0 = control()->in(0);
2079   if (i0 != NULL && i0->is_If()) {        // Found a guarding if test?
2080     IfNode *iff = i0->as_If();
2081     float f = iff->_prob;   // Get prob
2082     if (control()->Opcode() == Op_IfTrue) {
2083       if (f > PROB_UNLIKELY_MAG(4))
2084         iff->_prob = PROB_MIN;
2085     } else {
2086       if (f < PROB_LIKELY_MAG(4))
2087         iff->_prob = PROB_MAX;
2088     }
2089   }
2090 
2091   // Clear out dead values from the debug info.
2092   kill_dead_locals();
2093 
2094   // Now insert the uncommon trap subroutine call
2095   address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point();
2096   const TypePtr* no_memory_effects = NULL;
2097   // Pass the index of the class to be loaded
2098   Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2099                                  (must_throw ? RC_MUST_THROW : 0),
2100                                  OptoRuntime::uncommon_trap_Type(),
2101                                  call_addr, "uncommon_trap", no_memory_effects,
2102                                  intcon(trap_request));
2103   assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2104          "must extract request correctly from the graph");
2105   assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2106 
2107   call->set_req(TypeFunc::ReturnAdr, returnadr());
2108   // The debug info is the only real input to this call.
2109 
2110   // Halt-and-catch fire here.  The above call should never return!
2111   HaltNode* halt = new HaltNode(control(), frameptr());
2112   _gvn.set_type_bottom(halt);
2113   root()->add_req(halt);
2114 
2115   stop_and_kill_map();
2116 }
2117 
2118 
2119 //--------------------------just_allocated_object------------------------------
2120 // Report the object that was just allocated.
2121 // It must be the case that there are no intervening safepoints.
2122 // We use this to determine if an object is so "fresh" that
2123 // it does not require card marks.
2124 Node* GraphKit::just_allocated_object(Node* current_control) {
2125   if (C->recent_alloc_ctl() == current_control)
2126     return C->recent_alloc_obj();
2127   return NULL;
2128 }
2129 
2130 
2131 void GraphKit::round_double_arguments(ciMethod* dest_method) {
2132   // (Note:  TypeFunc::make has a cache that makes this fast.)
2133   const TypeFunc* tf    = TypeFunc::make(dest_method);
2134   int             nargs = tf->domain_sig()->cnt() - TypeFunc::Parms;
2135   for (int j = 0; j < nargs; j++) {
2136     const Type *targ = tf->domain_sig()->field_at(j + TypeFunc::Parms);
2137     if( targ->basic_type() == T_DOUBLE ) {
2138       // If any parameters are doubles, they must be rounded before
2139       // the call, dstore_rounding does gvn.transform
2140       Node *arg = argument(j);
2141       arg = dstore_rounding(arg);
2142       set_argument(j, arg);
2143     }
2144   }
2145 }
2146 
2147 /**
2148  * Record profiling data exact_kls for Node n with the type system so
2149  * that it can propagate it (speculation)
2150  *
2151  * @param n          node that the type applies to
2152  * @param exact_kls  type from profiling
2153  * @param maybe_null did profiling see null?
2154  *
2155  * @return           node with improved type
2156  */
2157 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls, bool maybe_null) {
2158   const Type* current_type = _gvn.type(n);
2159   assert(UseTypeSpeculation, "type speculation must be on");
2160 
2161   const TypePtr* speculative = current_type->speculative();
2162 
2163   // Should the klass from the profile be recorded in the speculative type?
2164   if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2165     const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls);
2166     const TypeOopPtr* xtype = tklass->as_instance_type();
2167     assert(xtype->klass_is_exact(), "Should be exact");
2168     // Any reason to believe n is not null (from this profiling or a previous one)?
2169     const TypePtr* ptr = (maybe_null && current_type->speculative_maybe_null()) ? TypePtr::BOTTOM : TypePtr::NOTNULL;
2170     // record the new speculative type's depth
2171     speculative = xtype->cast_to_ptr_type(ptr->ptr())->is_ptr();
2172     speculative = speculative->with_inline_depth(jvms()->depth());
2173   } else if (current_type->would_improve_ptr(maybe_null)) {
2174     // Profiling report that null was never seen so we can change the
2175     // speculative type to non null ptr.
2176     assert(!maybe_null, "nothing to improve");
2177     if (speculative == NULL) {
2178       speculative = TypePtr::NOTNULL;
2179     } else {
2180       const TypePtr* ptr = TypePtr::NOTNULL;
2181       speculative = speculative->cast_to_ptr_type(ptr->ptr())->is_ptr();
2182     }
2183   }
2184 
2185   if (speculative != current_type->speculative()) {
2186     // Build a type with a speculative type (what we think we know
2187     // about the type but will need a guard when we use it)
2188     const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2189     // We're changing the type, we need a new CheckCast node to carry
2190     // the new type. The new type depends on the control: what
2191     // profiling tells us is only valid from here as far as we can
2192     // tell.
2193     Node* cast = new CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2194     cast = _gvn.transform(cast);
2195     replace_in_map(n, cast);
2196     n = cast;
2197   }
2198 
2199   return n;
2200 }
2201 
2202 /**
2203  * Record profiling data from receiver profiling at an invoke with the
2204  * type system so that it can propagate it (speculation)
2205  *
2206  * @param n  receiver node
2207  *
2208  * @return   node with improved type
2209  */
2210 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2211   if (!UseTypeSpeculation) {
2212     return n;
2213   }
2214   ciKlass* exact_kls = profile_has_unique_klass();
2215   bool maybe_null = true;
2216   if (java_bc() == Bytecodes::_checkcast ||
2217       java_bc() == Bytecodes::_instanceof ||
2218       java_bc() == Bytecodes::_aastore) {
2219     ciProfileData* data = method()->method_data()->bci_to_data(bci());
2220     bool maybe_null = data == NULL ? true : data->as_BitData()->null_seen();
2221   }
2222   return record_profile_for_speculation(n, exact_kls, maybe_null);
2223   return n;
2224 }
2225 
2226 /**
2227  * Record profiling data from argument profiling at an invoke with the
2228  * type system so that it can propagate it (speculation)
2229  *
2230  * @param dest_method  target method for the call
2231  * @param bc           what invoke bytecode is this?
2232  */
2233 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2234   if (!UseTypeSpeculation) {
2235     return;
2236   }
2237   const TypeFunc* tf    = TypeFunc::make(dest_method);
2238   int             nargs = tf->domain_sig()->cnt() - TypeFunc::Parms;
2239   int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2240   for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2241     const Type *targ = tf->domain_sig()->field_at(j + TypeFunc::Parms);
2242     if (targ->basic_type() == T_OBJECT || targ->basic_type() == T_ARRAY) {
2243       bool maybe_null = true;
2244       ciKlass* better_type = NULL;
2245       if (method()->argument_profiled_type(bci(), i, better_type, maybe_null)) {
2246         record_profile_for_speculation(argument(j), better_type, maybe_null);
2247       }
2248       i++;
2249     }
2250   }
2251 }
2252 
2253 /**
2254  * Record profiling data from parameter profiling at an invoke with
2255  * the type system so that it can propagate it (speculation)
2256  */
2257 void GraphKit::record_profiled_parameters_for_speculation() {
2258   if (!UseTypeSpeculation) {
2259     return;
2260   }
2261   for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2262     if (_gvn.type(local(i))->isa_oopptr()) {
2263       bool maybe_null = true;
2264       ciKlass* better_type = NULL;
2265       if (method()->parameter_profiled_type(j, better_type, maybe_null)) {
2266         record_profile_for_speculation(local(i), better_type, maybe_null);
2267       }
2268       j++;
2269     }
2270   }
2271 }
2272 
2273 /**
2274  * Record profiling data from return value profiling at an invoke with
2275  * the type system so that it can propagate it (speculation)
2276  */
2277 void GraphKit::record_profiled_return_for_speculation() {
2278   if (!UseTypeSpeculation) {
2279     return;
2280   }
2281   bool maybe_null = true;
2282   ciKlass* better_type = NULL;
2283   if (method()->return_profiled_type(bci(), better_type, maybe_null)) {
2284     // If profiling reports a single type for the return value,
2285     // feed it to the type system so it can propagate it as a
2286     // speculative type
2287     record_profile_for_speculation(stack(sp()-1), better_type, maybe_null);
2288   }
2289 }
2290 
2291 void GraphKit::round_double_result(ciMethod* dest_method) {
2292   // A non-strict method may return a double value which has an extended
2293   // exponent, but this must not be visible in a caller which is 'strict'
2294   // If a strict caller invokes a non-strict callee, round a double result
2295 
2296   BasicType result_type = dest_method->return_type()->basic_type();
2297   assert( method() != NULL, "must have caller context");
2298   if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) {
2299     // Destination method's return value is on top of stack
2300     // dstore_rounding() does gvn.transform
2301     Node *result = pop_pair();
2302     result = dstore_rounding(result);
2303     push_pair(result);
2304   }
2305 }
2306 
2307 // rounding for strict float precision conformance
2308 Node* GraphKit::precision_rounding(Node* n) {
2309   return UseStrictFP && _method->flags().is_strict()
2310     && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding
2311     ? _gvn.transform( new RoundFloatNode(0, n) )
2312     : n;
2313 }
2314 
2315 // rounding for strict double precision conformance
2316 Node* GraphKit::dprecision_rounding(Node *n) {
2317   return UseStrictFP && _method->flags().is_strict()
2318     && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding
2319     ? _gvn.transform( new RoundDoubleNode(0, n) )
2320     : n;
2321 }
2322 
2323 // rounding for non-strict double stores
2324 Node* GraphKit::dstore_rounding(Node* n) {
2325   return Matcher::strict_fp_requires_explicit_rounding
2326     && UseSSE <= 1
2327     ? _gvn.transform( new RoundDoubleNode(0, n) )
2328     : n;
2329 }
2330 
2331 //=============================================================================
2332 // Generate a fast path/slow path idiom.  Graph looks like:
2333 // [foo] indicates that 'foo' is a parameter
2334 //
2335 //              [in]     NULL
2336 //                 \    /
2337 //                  CmpP
2338 //                  Bool ne
2339 //                   If
2340 //                  /  \
2341 //              True    False-<2>
2342 //              / |
2343 //             /  cast_not_null
2344 //           Load  |    |   ^
2345 //        [fast_test]   |   |
2346 // gvn to   opt_test    |   |
2347 //          /    \      |  <1>
2348 //      True     False  |
2349 //        |         \\  |
2350 //   [slow_call]     \[fast_result]
2351 //    Ctl   Val       \      \
2352 //     |               \      \
2353 //    Catch       <1>   \      \
2354 //   /    \        ^     \      \
2355 //  Ex    No_Ex    |      \      \
2356 //  |       \   \  |       \ <2>  \
2357 //  ...      \  [slow_res] |  |    \   [null_result]
2358 //            \         \--+--+---  |  |
2359 //             \           | /    \ | /
2360 //              --------Region     Phi
2361 //
2362 //=============================================================================
2363 // Code is structured as a series of driver functions all called 'do_XXX' that
2364 // call a set of helper functions.  Helper functions first, then drivers.
2365 
2366 //------------------------------null_check_oop---------------------------------
2367 // Null check oop.  Set null-path control into Region in slot 3.
2368 // Make a cast-not-nullness use the other not-null control.  Return cast.
2369 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2370                                bool never_see_null,
2371                                bool safe_for_replace,
2372                                bool speculative) {
2373   // Initial NULL check taken path
2374   (*null_control) = top();
2375   Node* cast = null_check_common(value, T_OBJECT, false, null_control, speculative);
2376 
2377   // Generate uncommon_trap:
2378   if (never_see_null && (*null_control) != top()) {
2379     // If we see an unexpected null at a check-cast we record it and force a
2380     // recompile; the offending check-cast will be compiled to handle NULLs.
2381     // If we see more than one offending BCI, then all checkcasts in the
2382     // method will be compiled to handle NULLs.
2383     PreserveJVMState pjvms(this);
2384     set_control(*null_control);
2385     replace_in_map(value, null());
2386     Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculative);
2387     uncommon_trap(reason,
2388                   Deoptimization::Action_make_not_entrant);
2389     (*null_control) = top();    // NULL path is dead
2390   }
2391   if ((*null_control) == top() && safe_for_replace) {
2392     replace_in_map(value, cast);
2393   }
2394 
2395   // Cast away null-ness on the result
2396   return cast;
2397 }
2398 
2399 //------------------------------opt_iff----------------------------------------
2400 // Optimize the fast-check IfNode.  Set the fast-path region slot 2.
2401 // Return slow-path control.
2402 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2403   IfNode *opt_iff = _gvn.transform(iff)->as_If();
2404 
2405   // Fast path taken; set region slot 2
2406   Node *fast_taken = _gvn.transform( new IfFalseNode(opt_iff) );
2407   region->init_req(2,fast_taken); // Capture fast-control
2408 
2409   // Fast path not-taken, i.e. slow path
2410   Node *slow_taken = _gvn.transform( new IfTrueNode(opt_iff) );
2411   return slow_taken;
2412 }
2413 
2414 //-----------------------------make_runtime_call-------------------------------
2415 Node* GraphKit::make_runtime_call(int flags,
2416                                   const TypeFunc* call_type, address call_addr,
2417                                   const char* call_name,
2418                                   const TypePtr* adr_type,
2419                                   // The following parms are all optional.
2420                                   // The first NULL ends the list.
2421                                   Node* parm0, Node* parm1,
2422                                   Node* parm2, Node* parm3,
2423                                   Node* parm4, Node* parm5,
2424                                   Node* parm6, Node* parm7) {
2425   // Slow-path call
2426   bool is_leaf = !(flags & RC_NO_LEAF);
2427   bool has_io  = (!is_leaf && !(flags & RC_NO_IO));
2428   if (call_name == NULL) {
2429     assert(!is_leaf, "must supply name for leaf");
2430     call_name = OptoRuntime::stub_name(call_addr);
2431   }
2432   CallNode* call;
2433   if (!is_leaf) {
2434     call = new CallStaticJavaNode(call_type, call_addr, call_name,
2435                                            bci(), adr_type);
2436   } else if (flags & RC_NO_FP) {
2437     call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2438   } else {
2439     call = new CallLeafNode(call_type, call_addr, call_name, adr_type);
2440   }
2441 
2442   // The following is similar to set_edges_for_java_call,
2443   // except that the memory effects of the call are restricted to AliasIdxRaw.
2444 
2445   // Slow path call has no side-effects, uses few values
2446   bool wide_in  = !(flags & RC_NARROW_MEM);
2447   bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2448 
2449   Node* prev_mem = NULL;
2450   if (wide_in) {
2451     prev_mem = set_predefined_input_for_runtime_call(call);
2452   } else {
2453     assert(!wide_out, "narrow in => narrow out");
2454     Node* narrow_mem = memory(adr_type);
2455     prev_mem = reset_memory();
2456     map()->set_memory(narrow_mem);
2457     set_predefined_input_for_runtime_call(call);
2458   }
2459 
2460   // Hook each parm in order.  Stop looking at the first NULL.
2461   if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0);
2462   if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1);
2463   if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2);
2464   if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3);
2465   if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4);
2466   if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5);
2467   if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6);
2468   if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7);
2469     /* close each nested if ===> */  } } } } } } } }
2470   assert(call->in(call->req()-1) != NULL, "must initialize all parms");
2471 
2472   if (!is_leaf) {
2473     // Non-leaves can block and take safepoints:
2474     add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2475   }
2476   // Non-leaves can throw exceptions:
2477   if (has_io) {
2478     call->set_req(TypeFunc::I_O, i_o());
2479   }
2480 
2481   if (flags & RC_UNCOMMON) {
2482     // Set the count to a tiny probability.  Cf. Estimate_Block_Frequency.
2483     // (An "if" probability corresponds roughly to an unconditional count.
2484     // Sort of.)
2485     call->set_cnt(PROB_UNLIKELY_MAG(4));
2486   }
2487 
2488   Node* c = _gvn.transform(call);
2489   assert(c == call, "cannot disappear");
2490 
2491   if (wide_out) {
2492     // Slow path call has full side-effects.
2493     set_predefined_output_for_runtime_call(call);
2494   } else {
2495     // Slow path call has few side-effects, and/or sets few values.
2496     set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2497   }
2498 
2499   if (has_io) {
2500     set_i_o(_gvn.transform(new ProjNode(call, TypeFunc::I_O)));
2501   }
2502   return call;
2503 
2504 }
2505 
2506 //------------------------------merge_memory-----------------------------------
2507 // Merge memory from one path into the current memory state.
2508 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2509   for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2510     Node* old_slice = mms.force_memory();
2511     Node* new_slice = mms.memory2();
2512     if (old_slice != new_slice) {
2513       PhiNode* phi;
2514       if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) {
2515         if (mms.is_empty()) {
2516           // clone base memory Phi's inputs for this memory slice
2517           assert(old_slice == mms.base_memory(), "sanity");
2518           phi = PhiNode::make(region, NULL, Type::MEMORY, mms.adr_type(C));
2519           _gvn.set_type(phi, Type::MEMORY);
2520           for (uint i = 1; i < phi->req(); i++) {
2521             phi->init_req(i, old_slice->in(i));
2522           }
2523         } else {
2524           phi = old_slice->as_Phi(); // Phi was generated already
2525         }
2526       } else {
2527         phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2528         _gvn.set_type(phi, Type::MEMORY);
2529       }
2530       phi->set_req(new_path, new_slice);
2531       mms.set_memory(phi);
2532     }
2533   }
2534 }
2535 
2536 //------------------------------make_slow_call_ex------------------------------
2537 // Make the exception handler hookups for the slow call
2538 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) {
2539   if (stopped())  return;
2540 
2541   // Make a catch node with just two handlers:  fall-through and catch-all
2542   Node* i_o  = _gvn.transform( new ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2543   Node* catc = _gvn.transform( new CatchNode(control(), i_o, 2) );
2544   Node* norm = _gvn.transform( new CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) );
2545   Node* excp = _gvn.transform( new CatchProjNode(catc, CatchProjNode::catch_all_index,    CatchProjNode::no_handler_bci) );
2546 
2547   { PreserveJVMState pjvms(this);
2548     set_control(excp);
2549     set_i_o(i_o);
2550 
2551     if (excp != top()) {
2552       if (deoptimize) {
2553         // Deoptimize if an exception is caught. Don't construct exception state in this case.
2554         uncommon_trap(Deoptimization::Reason_unhandled,
2555                       Deoptimization::Action_none);
2556       } else {
2557         // Create an exception state also.
2558         // Use an exact type if the caller has specified a specific exception.
2559         const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2560         Node*       ex_oop  = new CreateExNode(ex_type, control(), i_o);
2561         add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2562       }
2563     }
2564   }
2565 
2566   // Get the no-exception control from the CatchNode.
2567   set_control(norm);
2568 }
2569 
2570 static IfNode* gen_subtype_check_compare(Node* ctrl, Node* in1, Node* in2, BoolTest::mask test, float p, PhaseGVN* gvn, BasicType bt) {
2571   Node* cmp = NULL;
2572   switch(bt) {
2573   case T_INT: cmp = new CmpINode(in1, in2); break;
2574   case T_ADDRESS: cmp = new CmpPNode(in1, in2); break;
2575   default: fatal("unexpected comparison type %s", type2name(bt));
2576   }
2577   gvn->transform(cmp);
2578   Node* bol = gvn->transform(new BoolNode(cmp, test));
2579   IfNode* iff = new IfNode(ctrl, bol, p, COUNT_UNKNOWN);
2580   gvn->transform(iff);
2581   if (!bol->is_Con()) gvn->record_for_igvn(iff);
2582   return iff;
2583 }
2584 
2585 
2586 //-------------------------------gen_subtype_check-----------------------------
2587 // Generate a subtyping check.  Takes as input the subtype and supertype.
2588 // Returns 2 values: sets the default control() to the true path and returns
2589 // the false path.  Only reads invariant memory; sets no (visible) memory.
2590 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2591 // but that's not exposed to the optimizer.  This call also doesn't take in an
2592 // Object; if you wish to check an Object you need to load the Object's class
2593 // prior to coming here.
2594 Node* Phase::gen_subtype_check(Node* subklass, Node* superklass, Node** ctrl, MergeMemNode* mem, PhaseGVN* gvn) {
2595   Compile* C = gvn->C;
2596 
2597   if ((*ctrl)->is_top()) {
2598     return C->top();
2599   }
2600 
2601   // Fast check for identical types, perhaps identical constants.
2602   // The types can even be identical non-constants, in cases
2603   // involving Array.newInstance, Object.clone, etc.
2604   if (subklass == superklass)
2605     return C->top();             // false path is dead; no test needed.
2606 
2607   if (gvn->type(superklass)->singleton()) {
2608     ciKlass* superk = gvn->type(superklass)->is_klassptr()->klass();
2609     ciKlass* subk   = gvn->type(subklass)->is_klassptr()->klass();
2610 
2611     // In the common case of an exact superklass, try to fold up the
2612     // test before generating code.  You may ask, why not just generate
2613     // the code and then let it fold up?  The answer is that the generated
2614     // code will necessarily include null checks, which do not always
2615     // completely fold away.  If they are also needless, then they turn
2616     // into a performance loss.  Example:
2617     //    Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2618     // Here, the type of 'fa' is often exact, so the store check
2619     // of fa[1]=x will fold up, without testing the nullness of x.
2620     switch (C->static_subtype_check(superk, subk)) {
2621     case Compile::SSC_always_false:
2622       {
2623         Node* always_fail = *ctrl;
2624         *ctrl = gvn->C->top();
2625         return always_fail;
2626       }
2627     case Compile::SSC_always_true:
2628       return C->top();
2629     case Compile::SSC_easy_test:
2630       {
2631         // Just do a direct pointer compare and be done.
2632         IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_STATIC_FREQUENT, gvn, T_ADDRESS);
2633         *ctrl = gvn->transform(new IfTrueNode(iff));
2634         return gvn->transform(new IfFalseNode(iff));
2635       }
2636     case Compile::SSC_full_test:
2637       break;
2638     default:
2639       ShouldNotReachHere();
2640     }
2641   }
2642 
2643   // %%% Possible further optimization:  Even if the superklass is not exact,
2644   // if the subklass is the unique subtype of the superklass, the check
2645   // will always succeed.  We could leave a dependency behind to ensure this.
2646 
2647   // First load the super-klass's check-offset
2648   Node *p1 = gvn->transform(new AddPNode(superklass, superklass, gvn->MakeConX(in_bytes(Klass::super_check_offset_offset()))));
2649   Node* m = mem->memory_at(C->get_alias_index(gvn->type(p1)->is_ptr()));
2650   Node *chk_off = gvn->transform(new LoadINode(NULL, m, p1, gvn->type(p1)->is_ptr(), TypeInt::INT, MemNode::unordered));
2651   int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2652   bool might_be_cache = (gvn->find_int_con(chk_off, cacheoff_con) == cacheoff_con);
2653 
2654   // Load from the sub-klass's super-class display list, or a 1-word cache of
2655   // the secondary superclass list, or a failing value with a sentinel offset
2656   // if the super-klass is an interface or exceptionally deep in the Java
2657   // hierarchy and we have to scan the secondary superclass list the hard way.
2658   // Worst-case type is a little odd: NULL is allowed as a result (usually
2659   // klass loads can never produce a NULL).
2660   Node *chk_off_X = chk_off;
2661 #ifdef _LP64
2662   chk_off_X = gvn->transform(new ConvI2LNode(chk_off_X));
2663 #endif
2664   Node *p2 = gvn->transform(new AddPNode(subklass,subklass,chk_off_X));
2665   // For some types like interfaces the following loadKlass is from a 1-word
2666   // cache which is mutable so can't use immutable memory.  Other
2667   // types load from the super-class display table which is immutable.
2668   m = mem->memory_at(C->get_alias_index(gvn->type(p2)->is_ptr()));
2669   Node *kmem = might_be_cache ? m : C->immutable_memory();
2670   Node *nkls = gvn->transform(LoadKlassNode::make(*gvn, NULL, kmem, p2, gvn->type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL));
2671 
2672   // Compile speed common case: ARE a subtype and we canNOT fail
2673   if( superklass == nkls )
2674     return C->top();             // false path is dead; no test needed.
2675 
2676   // See if we get an immediate positive hit.  Happens roughly 83% of the
2677   // time.  Test to see if the value loaded just previously from the subklass
2678   // is exactly the superklass.
2679   IfNode *iff1 = gen_subtype_check_compare(*ctrl, superklass, nkls, BoolTest::eq, PROB_LIKELY(0.83f), gvn, T_ADDRESS);
2680   Node *iftrue1 = gvn->transform( new IfTrueNode (iff1));
2681   *ctrl = gvn->transform(new IfFalseNode(iff1));
2682 
2683   // Compile speed common case: Check for being deterministic right now.  If
2684   // chk_off is a constant and not equal to cacheoff then we are NOT a
2685   // subklass.  In this case we need exactly the 1 test above and we can
2686   // return those results immediately.
2687   if (!might_be_cache) {
2688     Node* not_subtype_ctrl = *ctrl;
2689     *ctrl = iftrue1; // We need exactly the 1 test above
2690     return not_subtype_ctrl;
2691   }
2692 
2693   // Gather the various success & failures here
2694   RegionNode *r_ok_subtype = new RegionNode(4);
2695   gvn->record_for_igvn(r_ok_subtype);
2696   RegionNode *r_not_subtype = new RegionNode(3);
2697   gvn->record_for_igvn(r_not_subtype);
2698 
2699   r_ok_subtype->init_req(1, iftrue1);
2700 
2701   // Check for immediate negative hit.  Happens roughly 11% of the time (which
2702   // is roughly 63% of the remaining cases).  Test to see if the loaded
2703   // check-offset points into the subklass display list or the 1-element
2704   // cache.  If it points to the display (and NOT the cache) and the display
2705   // missed then it's not a subtype.
2706   Node *cacheoff = gvn->intcon(cacheoff_con);
2707   IfNode *iff2 = gen_subtype_check_compare(*ctrl, chk_off, cacheoff, BoolTest::ne, PROB_LIKELY(0.63f), gvn, T_INT);
2708   r_not_subtype->init_req(1, gvn->transform(new IfTrueNode (iff2)));
2709   *ctrl = gvn->transform(new IfFalseNode(iff2));
2710 
2711   // Check for self.  Very rare to get here, but it is taken 1/3 the time.
2712   // No performance impact (too rare) but allows sharing of secondary arrays
2713   // which has some footprint reduction.
2714   IfNode *iff3 = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_LIKELY(0.36f), gvn, T_ADDRESS);
2715   r_ok_subtype->init_req(2, gvn->transform(new IfTrueNode(iff3)));
2716   *ctrl = gvn->transform(new IfFalseNode(iff3));
2717 
2718   // -- Roads not taken here: --
2719   // We could also have chosen to perform the self-check at the beginning
2720   // of this code sequence, as the assembler does.  This would not pay off
2721   // the same way, since the optimizer, unlike the assembler, can perform
2722   // static type analysis to fold away many successful self-checks.
2723   // Non-foldable self checks work better here in second position, because
2724   // the initial primary superclass check subsumes a self-check for most
2725   // types.  An exception would be a secondary type like array-of-interface,
2726   // which does not appear in its own primary supertype display.
2727   // Finally, we could have chosen to move the self-check into the
2728   // PartialSubtypeCheckNode, and from there out-of-line in a platform
2729   // dependent manner.  But it is worthwhile to have the check here,
2730   // where it can be perhaps be optimized.  The cost in code space is
2731   // small (register compare, branch).
2732 
2733   // Now do a linear scan of the secondary super-klass array.  Again, no real
2734   // performance impact (too rare) but it's gotta be done.
2735   // Since the code is rarely used, there is no penalty for moving it
2736   // out of line, and it can only improve I-cache density.
2737   // The decision to inline or out-of-line this final check is platform
2738   // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2739   Node* psc = gvn->transform(
2740     new PartialSubtypeCheckNode(*ctrl, subklass, superklass));
2741 
2742   IfNode *iff4 = gen_subtype_check_compare(*ctrl, psc, gvn->zerocon(T_OBJECT), BoolTest::ne, PROB_FAIR, gvn, T_ADDRESS);
2743   r_not_subtype->init_req(2, gvn->transform(new IfTrueNode (iff4)));
2744   r_ok_subtype ->init_req(3, gvn->transform(new IfFalseNode(iff4)));
2745 
2746   // Return false path; set default control to true path.
2747   *ctrl = gvn->transform(r_ok_subtype);
2748   return gvn->transform(r_not_subtype);
2749 }
2750 
2751 // Profile-driven exact type check:
2752 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2753                                     float prob,
2754                                     Node* *casted_receiver) {
2755   const TypeKlassPtr* tklass = TypeKlassPtr::make(klass);
2756   Node* recv_klass = load_object_klass(receiver);
2757   Node* want_klass = makecon(tklass);
2758   Node* cmp = _gvn.transform( new CmpPNode(recv_klass, want_klass) );
2759   Node* bol = _gvn.transform( new BoolNode(cmp, BoolTest::eq) );
2760   IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2761   set_control( _gvn.transform( new IfTrueNode (iff) ));
2762   Node* fail = _gvn.transform( new IfFalseNode(iff) );
2763 
2764   const TypeOopPtr* recv_xtype = tklass->as_instance_type();
2765   assert(recv_xtype->klass_is_exact(), "");
2766 
2767   // Subsume downstream occurrences of receiver with a cast to
2768   // recv_xtype, since now we know what the type will be.
2769   Node* cast = new CheckCastPPNode(control(), receiver, recv_xtype);
2770   (*casted_receiver) = _gvn.transform(cast);
2771   // (User must make the replace_in_map call.)
2772 
2773   return fail;
2774 }
2775 
2776 
2777 //------------------------------seems_never_null-------------------------------
2778 // Use null_seen information if it is available from the profile.
2779 // If we see an unexpected null at a type check we record it and force a
2780 // recompile; the offending check will be recompiled to handle NULLs.
2781 // If we see several offending BCIs, then all checks in the
2782 // method will be recompiled.
2783 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data, bool& speculating) {
2784   speculating = !_gvn.type(obj)->speculative_maybe_null();
2785   Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculating);
2786   if (UncommonNullCast               // Cutout for this technique
2787       && obj != null()               // And not the -Xcomp stupid case?
2788       && !too_many_traps(reason)
2789       ) {
2790     if (speculating) {
2791       return true;
2792     }
2793     if (data == NULL)
2794       // Edge case:  no mature data.  Be optimistic here.
2795       return true;
2796     // If the profile has not seen a null, assume it won't happen.
2797     assert(java_bc() == Bytecodes::_checkcast ||
2798            java_bc() == Bytecodes::_instanceof ||
2799            java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
2800     return !data->as_BitData()->null_seen();
2801   }
2802   speculating = false;
2803   return false;
2804 }
2805 
2806 //------------------------maybe_cast_profiled_receiver-------------------------
2807 // If the profile has seen exactly one type, narrow to exactly that type.
2808 // Subsequent type checks will always fold up.
2809 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
2810                                              ciKlass* require_klass,
2811                                              ciKlass* spec_klass,
2812                                              bool safe_for_replace) {
2813   if (!UseTypeProfile || !TypeProfileCasts) return NULL;
2814 
2815   Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != NULL);
2816 
2817   // Make sure we haven't already deoptimized from this tactic.
2818   if (too_many_traps(reason) || too_many_recompiles(reason))
2819     return NULL;
2820 
2821   // (No, this isn't a call, but it's enough like a virtual call
2822   // to use the same ciMethod accessor to get the profile info...)
2823   // If we have a speculative type use it instead of profiling (which
2824   // may not help us)
2825   ciKlass* exact_kls = spec_klass == NULL ? profile_has_unique_klass() : spec_klass;
2826   if (exact_kls != NULL) {// no cast failures here
2827     if (require_klass == NULL ||
2828         C->static_subtype_check(require_klass, exact_kls) == Compile::SSC_always_true) {
2829       // If we narrow the type to match what the type profile sees or
2830       // the speculative type, we can then remove the rest of the
2831       // cast.
2832       // This is a win, even if the exact_kls is very specific,
2833       // because downstream operations, such as method calls,
2834       // will often benefit from the sharper type.
2835       Node* exact_obj = not_null_obj; // will get updated in place...
2836       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
2837                                             &exact_obj);
2838       { PreserveJVMState pjvms(this);
2839         set_control(slow_ctl);
2840         uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile);
2841       }
2842       if (safe_for_replace) {
2843         replace_in_map(not_null_obj, exact_obj);
2844       }
2845       return exact_obj;
2846     }
2847     // assert(ssc == Compile::SSC_always_true)... except maybe the profile lied to us.
2848   }
2849 
2850   return NULL;
2851 }
2852 
2853 /**
2854  * Cast obj to type and emit guard unless we had too many traps here
2855  * already
2856  *
2857  * @param obj       node being casted
2858  * @param type      type to cast the node to
2859  * @param not_null  true if we know node cannot be null
2860  */
2861 Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
2862                                         ciKlass* type,
2863                                         bool not_null) {
2864   if (stopped()) {
2865     return obj;
2866   }
2867 
2868   // type == NULL if profiling tells us this object is always null
2869   if (type != NULL) {
2870     Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
2871     Deoptimization::DeoptReason null_reason = Deoptimization::Reason_speculate_null_check;
2872 
2873     if (!too_many_traps(null_reason) && !too_many_recompiles(null_reason) &&
2874         !too_many_traps(class_reason) &&
2875         !too_many_recompiles(class_reason)) {
2876       Node* not_null_obj = NULL;
2877       // not_null is true if we know the object is not null and
2878       // there's no need for a null check
2879       if (!not_null) {
2880         Node* null_ctl = top();
2881         not_null_obj = null_check_oop(obj, &null_ctl, true, true, true);
2882         assert(null_ctl->is_top(), "no null control here");
2883       } else {
2884         not_null_obj = obj;
2885       }
2886 
2887       Node* exact_obj = not_null_obj;
2888       ciKlass* exact_kls = type;
2889       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
2890                                             &exact_obj);
2891       {
2892         PreserveJVMState pjvms(this);
2893         set_control(slow_ctl);
2894         uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile);
2895       }
2896       replace_in_map(not_null_obj, exact_obj);
2897       obj = exact_obj;
2898     }
2899   } else {
2900     if (!too_many_traps(Deoptimization::Reason_null_assert) &&
2901         !too_many_recompiles(Deoptimization::Reason_null_assert)) {
2902       Node* exact_obj = null_assert(obj);
2903       replace_in_map(obj, exact_obj);
2904       obj = exact_obj;
2905     }
2906   }
2907   return obj;
2908 }
2909 
2910 //-------------------------------gen_instanceof--------------------------------
2911 // Generate an instance-of idiom.  Used by both the instance-of bytecode
2912 // and the reflective instance-of call.
2913 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
2914   kill_dead_locals();           // Benefit all the uncommon traps
2915   assert( !stopped(), "dead parse path should be checked in callers" );
2916   assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
2917          "must check for not-null not-dead klass in callers");
2918 
2919   // Make the merge point
2920   enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
2921   RegionNode* region = new RegionNode(PATH_LIMIT);
2922   Node*       phi    = new PhiNode(region, TypeInt::BOOL);
2923   C->set_has_split_ifs(true); // Has chance for split-if optimization
2924 
2925   ciProfileData* data = NULL;
2926   if (java_bc() == Bytecodes::_instanceof) {  // Only for the bytecode
2927     data = method()->method_data()->bci_to_data(bci());
2928   }
2929   bool speculative_not_null = false;
2930   bool never_see_null = (ProfileDynamicTypes  // aggressive use of profile
2931                          && seems_never_null(obj, data, speculative_not_null));
2932 
2933   // Null check; get casted pointer; set region slot 3
2934   Node* null_ctl = top();
2935   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
2936 
2937   // If not_null_obj is dead, only null-path is taken
2938   if (stopped()) {              // Doing instance-of on a NULL?
2939     set_control(null_ctl);
2940     return intcon(0);
2941   }
2942   region->init_req(_null_path, null_ctl);
2943   phi   ->init_req(_null_path, intcon(0)); // Set null path value
2944   if (null_ctl == top()) {
2945     // Do this eagerly, so that pattern matches like is_diamond_phi
2946     // will work even during parsing.
2947     assert(_null_path == PATH_LIMIT-1, "delete last");
2948     region->del_req(_null_path);
2949     phi   ->del_req(_null_path);
2950   }
2951 
2952   // Do we know the type check always succeed?
2953   bool known_statically = false;
2954   if (_gvn.type(superklass)->singleton()) {
2955     ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2956     ciKlass* subk = _gvn.type(obj)->is_oopptr()->klass();
2957     if (subk != NULL && subk->is_loaded()) {
2958       int static_res = C->static_subtype_check(superk, subk);
2959       known_statically = (static_res == Compile::SSC_always_true || static_res == Compile::SSC_always_false);
2960     }
2961   }
2962 
2963   if (known_statically && UseTypeSpeculation) {
2964     // If we know the type check always succeeds then we don't use the
2965     // profiling data at this bytecode. Don't lose it, feed it to the
2966     // type system as a speculative type.
2967     not_null_obj = record_profiled_receiver_for_speculation(not_null_obj);
2968   } else {
2969     const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
2970     // We may not have profiling here or it may not help us. If we
2971     // have a speculative type use it to perform an exact cast.
2972     ciKlass* spec_obj_type = obj_type->speculative_type();
2973     if (spec_obj_type != NULL || (ProfileDynamicTypes && data != NULL)) {
2974       Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, NULL, spec_obj_type, safe_for_replace);
2975       if (stopped()) {            // Profile disagrees with this path.
2976         set_control(null_ctl);    // Null is the only remaining possibility.
2977         return intcon(0);
2978       }
2979       if (cast_obj != NULL) {
2980         not_null_obj = cast_obj;
2981       }
2982     }
2983   }
2984 
2985   // Load the object's klass
2986   Node* obj_klass = load_object_klass(not_null_obj);
2987 
2988   // Generate the subtype check
2989   Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass);
2990 
2991   // Plug in the success path to the general merge in slot 1.
2992   region->init_req(_obj_path, control());
2993   phi   ->init_req(_obj_path, intcon(1));
2994 
2995   // Plug in the failing path to the general merge in slot 2.
2996   region->init_req(_fail_path, not_subtype_ctrl);
2997   phi   ->init_req(_fail_path, intcon(0));
2998 
2999   // Return final merged results
3000   set_control( _gvn.transform(region) );
3001   record_for_igvn(region);
3002   return _gvn.transform(phi);
3003 }
3004 
3005 //-------------------------------gen_checkcast---------------------------------
3006 // Generate a checkcast idiom.  Used by both the checkcast bytecode and the
3007 // array store bytecode.  Stack must be as-if BEFORE doing the bytecode so the
3008 // uncommon-trap paths work.  Adjust stack after this call.
3009 // If failure_control is supplied and not null, it is filled in with
3010 // the control edge for the cast failure.  Otherwise, an appropriate
3011 // uncommon trap or exception is thrown.
3012 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
3013                               Node* *failure_control) {
3014   kill_dead_locals();           // Benefit all the uncommon traps
3015   const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr();
3016   const Type *toop = TypeOopPtr::make_from_klass(tk->klass());
3017 
3018   // Fast cutout:  Check the case that the cast is vacuously true.
3019   // This detects the common cases where the test will short-circuit
3020   // away completely.  We do this before we perform the null check,
3021   // because if the test is going to turn into zero code, we don't
3022   // want a residual null check left around.  (Causes a slowdown,
3023   // for example, in some objArray manipulations, such as a[i]=a[j].)
3024   if (tk->singleton()) {
3025     const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
3026     if (objtp != NULL && objtp->klass() != NULL) {
3027       switch (C->static_subtype_check(tk->klass(), objtp->klass())) {
3028       case Compile::SSC_always_true:
3029         // If we know the type check always succeed then we don't use
3030         // the profiling data at this bytecode. Don't lose it, feed it
3031         // to the type system as a speculative type.
3032         return record_profiled_receiver_for_speculation(obj);
3033       case Compile::SSC_always_false:
3034         // It needs a null check because a null will *pass* the cast check.
3035         // A non-null value will always produce an exception.
3036         return null_assert(obj);
3037       }
3038     }
3039   }
3040 
3041   ciProfileData* data = NULL;
3042   bool safe_for_replace = false;
3043   if (failure_control == NULL) {        // use MDO in regular case only
3044     assert(java_bc() == Bytecodes::_aastore ||
3045            java_bc() == Bytecodes::_checkcast,
3046            "interpreter profiles type checks only for these BCs");
3047     data = method()->method_data()->bci_to_data(bci());
3048     safe_for_replace = true;
3049   }
3050 
3051   // Make the merge point
3052   enum { _obj_path = 1, _null_path, PATH_LIMIT };
3053   RegionNode* region = new RegionNode(PATH_LIMIT);
3054   Node*       phi    = new PhiNode(region, toop);
3055   C->set_has_split_ifs(true); // Has chance for split-if optimization
3056 
3057   // Use null-cast information if it is available
3058   bool speculative_not_null = false;
3059   bool never_see_null = ((failure_control == NULL)  // regular case only
3060                          && seems_never_null(obj, data, speculative_not_null));
3061 
3062   // Null check; get casted pointer; set region slot 3
3063   Node* null_ctl = top();
3064   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3065 
3066   // If not_null_obj is dead, only null-path is taken
3067   if (stopped()) {              // Doing instance-of on a NULL?
3068     set_control(null_ctl);
3069     return null();
3070   }
3071   region->init_req(_null_path, null_ctl);
3072   phi   ->init_req(_null_path, null());  // Set null path value
3073   if (null_ctl == top()) {
3074     // Do this eagerly, so that pattern matches like is_diamond_phi
3075     // will work even during parsing.
3076     assert(_null_path == PATH_LIMIT-1, "delete last");
3077     region->del_req(_null_path);
3078     phi   ->del_req(_null_path);
3079   }
3080 
3081   Node* cast_obj = NULL;
3082   if (tk->klass_is_exact()) {
3083     // The following optimization tries to statically cast the speculative type of the object
3084     // (for example obtained during profiling) to the type of the superklass and then do a
3085     // dynamic check that the type of the object is what we expect. To work correctly
3086     // for checkcast and aastore the type of superklass should be exact.
3087     const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3088     // We may not have profiling here or it may not help us. If we have
3089     // a speculative type use it to perform an exact cast.
3090     ciKlass* spec_obj_type = obj_type->speculative_type();
3091     if (spec_obj_type != NULL || data != NULL) {
3092       cast_obj = maybe_cast_profiled_receiver(not_null_obj, tk->klass(), spec_obj_type, safe_for_replace);
3093       if (cast_obj != NULL) {
3094         if (failure_control != NULL) // failure is now impossible
3095           (*failure_control) = top();
3096         // adjust the type of the phi to the exact klass:
3097         phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3098       }
3099     }
3100   }
3101 
3102   if (cast_obj == NULL) {
3103     // Load the object's klass
3104     Node* obj_klass = load_object_klass(not_null_obj);
3105 
3106     // Generate the subtype check
3107     Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass );
3108 
3109     // Plug in success path into the merge
3110     cast_obj = _gvn.transform(new CheckCastPPNode(control(), not_null_obj, toop));
3111     // Failure path ends in uncommon trap (or may be dead - failure impossible)
3112     if (failure_control == NULL) {
3113       if (not_subtype_ctrl != top()) { // If failure is possible
3114         PreserveJVMState pjvms(this);
3115         set_control(not_subtype_ctrl);
3116         builtin_throw(Deoptimization::Reason_class_check, obj_klass);
3117       }
3118     } else {
3119       (*failure_control) = not_subtype_ctrl;
3120     }
3121   }
3122 
3123   region->init_req(_obj_path, control());
3124   phi   ->init_req(_obj_path, cast_obj);
3125 
3126   // A merge of NULL or Casted-NotNull obj
3127   Node* res = _gvn.transform(phi);
3128 
3129   // Note I do NOT always 'replace_in_map(obj,result)' here.
3130   //  if( tk->klass()->can_be_primary_super()  )
3131     // This means that if I successfully store an Object into an array-of-String
3132     // I 'forget' that the Object is really now known to be a String.  I have to
3133     // do this because we don't have true union types for interfaces - if I store
3134     // a Baz into an array-of-Interface and then tell the optimizer it's an
3135     // Interface, I forget that it's also a Baz and cannot do Baz-like field
3136     // references to it.  FIX THIS WHEN UNION TYPES APPEAR!
3137   //  replace_in_map( obj, res );
3138 
3139   // Return final merged results
3140   set_control( _gvn.transform(region) );
3141   record_for_igvn(region);
3142   return res;
3143 }
3144 
3145 //------------------------------next_monitor-----------------------------------
3146 // What number should be given to the next monitor?
3147 int GraphKit::next_monitor() {
3148   int current = jvms()->monitor_depth()* C->sync_stack_slots();
3149   int next = current + C->sync_stack_slots();
3150   // Keep the toplevel high water mark current:
3151   if (C->fixed_slots() < next)  C->set_fixed_slots(next);
3152   return current;
3153 }
3154 
3155 //------------------------------insert_mem_bar---------------------------------
3156 // Memory barrier to avoid floating things around
3157 // The membar serves as a pinch point between both control and all memory slices.
3158 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3159   MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3160   mb->init_req(TypeFunc::Control, control());
3161   mb->init_req(TypeFunc::Memory,  reset_memory());
3162   Node* membar = _gvn.transform(mb);
3163   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3164   set_all_memory_call(membar);
3165   return membar;
3166 }
3167 
3168 //-------------------------insert_mem_bar_volatile----------------------------
3169 // Memory barrier to avoid floating things around
3170 // The membar serves as a pinch point between both control and memory(alias_idx).
3171 // If you want to make a pinch point on all memory slices, do not use this
3172 // function (even with AliasIdxBot); use insert_mem_bar() instead.
3173 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3174   // When Parse::do_put_xxx updates a volatile field, it appends a series
3175   // of MemBarVolatile nodes, one for *each* volatile field alias category.
3176   // The first membar is on the same memory slice as the field store opcode.
3177   // This forces the membar to follow the store.  (Bug 6500685 broke this.)
3178   // All the other membars (for other volatile slices, including AliasIdxBot,
3179   // which stands for all unknown volatile slices) are control-dependent
3180   // on the first membar.  This prevents later volatile loads or stores
3181   // from sliding up past the just-emitted store.
3182 
3183   MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3184   mb->set_req(TypeFunc::Control,control());
3185   if (alias_idx == Compile::AliasIdxBot) {
3186     mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3187   } else {
3188     assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3189     mb->set_req(TypeFunc::Memory, memory(alias_idx));
3190   }
3191   Node* membar = _gvn.transform(mb);
3192   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3193   if (alias_idx == Compile::AliasIdxBot) {
3194     merged_memory()->set_base_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)));
3195   } else {
3196     set_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)),alias_idx);
3197   }
3198   return membar;
3199 }
3200 
3201 void GraphKit::insert_store_load_for_barrier() {
3202   Node* mem = reset_memory();
3203   MemBarNode* mb = MemBarNode::make(C, Op_MemBarVolatile, Compile::AliasIdxBot);
3204   mb->init_req(TypeFunc::Control, control());
3205   mb->init_req(TypeFunc::Memory, mem);
3206   Node* membar = _gvn.transform(mb);
3207   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3208   Node* newmem = _gvn.transform(new ProjNode(membar, TypeFunc::Memory));
3209   set_all_memory(mem);
3210   set_memory(newmem, Compile::AliasIdxRaw);
3211 }
3212 
3213 
3214 //------------------------------shared_lock------------------------------------
3215 // Emit locking code.
3216 FastLockNode* GraphKit::shared_lock(Node* obj) {
3217   // bci is either a monitorenter bc or InvocationEntryBci
3218   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3219   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3220 
3221   if( !GenerateSynchronizationCode )
3222     return NULL;                // Not locking things?
3223   if (stopped())                // Dead monitor?
3224     return NULL;
3225 
3226   assert(dead_locals_are_killed(), "should kill locals before sync. point");
3227 
3228   // Box the stack location
3229   Node* box = _gvn.transform(new BoxLockNode(next_monitor()));
3230   Node* mem = reset_memory();
3231 
3232   FastLockNode * flock = _gvn.transform(new FastLockNode(0, obj, box) )->as_FastLock();
3233   if (UseBiasedLocking && PrintPreciseBiasedLockingStatistics) {
3234     // Create the counters for this fast lock.
3235     flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3236   }
3237 
3238   // Create the rtm counters for this fast lock if needed.
3239   flock->create_rtm_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3240 
3241   // Add monitor to debug info for the slow path.  If we block inside the
3242   // slow path and de-opt, we need the monitor hanging around
3243   map()->push_monitor( flock );
3244 
3245   const TypeFunc *tf = LockNode::lock_type();
3246   LockNode *lock = new LockNode(C, tf);
3247 
3248   lock->init_req( TypeFunc::Control, control() );
3249   lock->init_req( TypeFunc::Memory , mem );
3250   lock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
3251   lock->init_req( TypeFunc::FramePtr, frameptr() );
3252   lock->init_req( TypeFunc::ReturnAdr, top() );
3253 
3254   lock->init_req(TypeFunc::Parms + 0, obj);
3255   lock->init_req(TypeFunc::Parms + 1, box);
3256   lock->init_req(TypeFunc::Parms + 2, flock);
3257   add_safepoint_edges(lock);
3258 
3259   lock = _gvn.transform( lock )->as_Lock();
3260 
3261   // lock has no side-effects, sets few values
3262   set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3263 
3264   insert_mem_bar(Op_MemBarAcquireLock);
3265 
3266   // Add this to the worklist so that the lock can be eliminated
3267   record_for_igvn(lock);
3268 
3269 #ifndef PRODUCT
3270   if (PrintLockStatistics) {
3271     // Update the counter for this lock.  Don't bother using an atomic
3272     // operation since we don't require absolute accuracy.
3273     lock->create_lock_counter(map()->jvms());
3274     increment_counter(lock->counter()->addr());
3275   }
3276 #endif
3277 
3278   return flock;
3279 }
3280 
3281 
3282 //------------------------------shared_unlock----------------------------------
3283 // Emit unlocking code.
3284 void GraphKit::shared_unlock(Node* box, Node* obj) {
3285   // bci is either a monitorenter bc or InvocationEntryBci
3286   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3287   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3288 
3289   if( !GenerateSynchronizationCode )
3290     return;
3291   if (stopped()) {               // Dead monitor?
3292     map()->pop_monitor();        // Kill monitor from debug info
3293     return;
3294   }
3295 
3296   // Memory barrier to avoid floating things down past the locked region
3297   insert_mem_bar(Op_MemBarReleaseLock);
3298 
3299   const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3300   UnlockNode *unlock = new UnlockNode(C, tf);
3301 #ifdef ASSERT
3302   unlock->set_dbg_jvms(sync_jvms());
3303 #endif
3304   uint raw_idx = Compile::AliasIdxRaw;
3305   unlock->init_req( TypeFunc::Control, control() );
3306   unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3307   unlock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
3308   unlock->init_req( TypeFunc::FramePtr, frameptr() );
3309   unlock->init_req( TypeFunc::ReturnAdr, top() );
3310 
3311   unlock->init_req(TypeFunc::Parms + 0, obj);
3312   unlock->init_req(TypeFunc::Parms + 1, box);
3313   unlock = _gvn.transform(unlock)->as_Unlock();
3314 
3315   Node* mem = reset_memory();
3316 
3317   // unlock has no side-effects, sets few values
3318   set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3319 
3320   // Kill monitor from debug info
3321   map()->pop_monitor( );
3322 }
3323 
3324 //-------------------------------get_layout_helper-----------------------------
3325 // If the given klass is a constant or known to be an array,
3326 // fetch the constant layout helper value into constant_value
3327 // and return (Node*)NULL.  Otherwise, load the non-constant
3328 // layout helper value, and return the node which represents it.
3329 // This two-faced routine is useful because allocation sites
3330 // almost always feature constant types.
3331 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3332   const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr();
3333   if (!StressReflectiveCode && inst_klass != NULL) {
3334     ciKlass* klass = inst_klass->klass();
3335     bool    xklass = inst_klass->klass_is_exact();
3336     if (xklass || klass->is_array_klass()) {
3337       jint lhelper = klass->layout_helper();
3338       if (lhelper != Klass::_lh_neutral_value) {
3339         constant_value = lhelper;
3340         return (Node*) NULL;
3341       }
3342     }
3343   }
3344   constant_value = Klass::_lh_neutral_value;  // put in a known value
3345   Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
3346   return make_load(NULL, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3347 }
3348 
3349 // We just put in an allocate/initialize with a big raw-memory effect.
3350 // Hook selected additional alias categories on the initialization.
3351 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3352                                 MergeMemNode* init_in_merge,
3353                                 Node* init_out_raw) {
3354   DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3355   assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3356 
3357   Node* prevmem = kit.memory(alias_idx);
3358   init_in_merge->set_memory_at(alias_idx, prevmem);
3359   kit.set_memory(init_out_raw, alias_idx);
3360 }
3361 
3362 //---------------------------set_output_for_allocation-------------------------
3363 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3364                                           const TypeOopPtr* oop_type,
3365                                           bool deoptimize_on_exception) {
3366   int rawidx = Compile::AliasIdxRaw;
3367   alloc->set_req( TypeFunc::FramePtr, frameptr() );
3368   add_safepoint_edges(alloc);
3369   Node* allocx = _gvn.transform(alloc);
3370   set_control( _gvn.transform(new ProjNode(allocx, TypeFunc::Control) ) );
3371   // create memory projection for i_o
3372   set_memory ( _gvn.transform( new ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3373   make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception);
3374 
3375   // create a memory projection as for the normal control path
3376   Node* malloc = _gvn.transform(new ProjNode(allocx, TypeFunc::Memory));
3377   set_memory(malloc, rawidx);
3378 
3379   // a normal slow-call doesn't change i_o, but an allocation does
3380   // we create a separate i_o projection for the normal control path
3381   set_i_o(_gvn.transform( new ProjNode(allocx, TypeFunc::I_O, false) ) );
3382   Node* rawoop = _gvn.transform( new ProjNode(allocx, TypeFunc::Parms) );
3383 
3384   // put in an initialization barrier
3385   InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3386                                                  rawoop)->as_Initialize();
3387   assert(alloc->initialization() == init,  "2-way macro link must work");
3388   assert(init ->allocation()     == alloc, "2-way macro link must work");
3389   {
3390     // Extract memory strands which may participate in the new object's
3391     // initialization, and source them from the new InitializeNode.
3392     // This will allow us to observe initializations when they occur,
3393     // and link them properly (as a group) to the InitializeNode.
3394     assert(init->in(InitializeNode::Memory) == malloc, "");
3395     MergeMemNode* minit_in = MergeMemNode::make(malloc);
3396     init->set_req(InitializeNode::Memory, minit_in);
3397     record_for_igvn(minit_in); // fold it up later, if possible
3398     Node* minit_out = memory(rawidx);
3399     assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3400     if (oop_type->isa_aryptr()) {
3401       const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3402       int            elemidx  = C->get_alias_index(telemref);
3403       hook_memory_on_init(*this, elemidx, minit_in, minit_out);
3404     } else if (oop_type->isa_instptr() || oop_type->isa_valuetypeptr()) {
3405       ciInstanceKlass* ik = oop_type->klass()->as_instance_klass();
3406       for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3407         ciField* field = ik->nonstatic_field_at(i);
3408         if (field->offset() >= TrackedInitializationLimit * HeapWordSize)
3409           continue;  // do not bother to track really large numbers of fields
3410         // Find (or create) the alias category for this field:
3411         int fieldidx = C->alias_type(field)->index();
3412         hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3413       }
3414     }
3415   }
3416 
3417   // Cast raw oop to the real thing...
3418   Node* javaoop = new CheckCastPPNode(control(), rawoop, oop_type);
3419   javaoop = _gvn.transform(javaoop);
3420   C->set_recent_alloc(control(), javaoop);
3421   assert(just_allocated_object(control()) == javaoop, "just allocated");
3422 
3423 #ifdef ASSERT
3424   { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3425     assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc,
3426            "Ideal_allocation works");
3427     assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc,
3428            "Ideal_allocation works");
3429     if (alloc->is_AllocateArray()) {
3430       assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(),
3431              "Ideal_allocation works");
3432       assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(),
3433              "Ideal_allocation works");
3434     } else {
3435       assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3436     }
3437   }
3438 #endif //ASSERT
3439 
3440   return javaoop;
3441 }
3442 
3443 //---------------------------new_instance--------------------------------------
3444 // This routine takes a klass_node which may be constant (for a static type)
3445 // or may be non-constant (for reflective code).  It will work equally well
3446 // for either, and the graph will fold nicely if the optimizer later reduces
3447 // the type to a constant.
3448 // The optional arguments are for specialized use by intrinsics:
3449 //  - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3450 //  - If 'return_size_val', report the the total object size to the caller.
3451 //  - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3452 Node* GraphKit::new_instance(Node* klass_node,
3453                              Node* extra_slow_test,
3454                              Node* *return_size_val,
3455                              bool deoptimize_on_exception) {
3456   // Compute size in doublewords
3457   // The size is always an integral number of doublewords, represented
3458   // as a positive bytewise size stored in the klass's layout_helper.
3459   // The layout_helper also encodes (in a low bit) the need for a slow path.
3460   jint  layout_con = Klass::_lh_neutral_value;
3461   Node* layout_val = get_layout_helper(klass_node, layout_con);
3462   int   layout_is_con = (layout_val == NULL);
3463 
3464   if (extra_slow_test == NULL)  extra_slow_test = intcon(0);
3465   // Generate the initial go-slow test.  It's either ALWAYS (return a
3466   // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective
3467   // case) a computed value derived from the layout_helper.
3468   Node* initial_slow_test = NULL;
3469   if (layout_is_con) {
3470     assert(!StressReflectiveCode, "stress mode does not use these paths");
3471     bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3472     initial_slow_test = must_go_slow ? intcon(1) : extra_slow_test;
3473   } else {   // reflective case
3474     // This reflective path is used by Unsafe.allocateInstance.
3475     // (It may be stress-tested by specifying StressReflectiveCode.)
3476     // Basically, we want to get into the VM is there's an illegal argument.
3477     Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3478     initial_slow_test = _gvn.transform( new AndINode(layout_val, bit) );
3479     if (extra_slow_test != intcon(0)) {
3480       initial_slow_test = _gvn.transform( new OrINode(initial_slow_test, extra_slow_test) );
3481     }
3482     // (Macro-expander will further convert this to a Bool, if necessary.)
3483   }
3484 
3485   // Find the size in bytes.  This is easy; it's the layout_helper.
3486   // The size value must be valid even if the slow path is taken.
3487   Node* size = NULL;
3488   if (layout_is_con) {
3489     size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3490   } else {   // reflective case
3491     // This reflective path is used by clone and Unsafe.allocateInstance.
3492     size = ConvI2X(layout_val);
3493 
3494     // Clear the low bits to extract layout_helper_size_in_bytes:
3495     assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3496     Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3497     size = _gvn.transform( new AndXNode(size, mask) );
3498   }
3499   if (return_size_val != NULL) {
3500     (*return_size_val) = size;
3501   }
3502 
3503   // This is a precise notnull oop of the klass.
3504   // (Actually, it need not be precise if this is a reflective allocation.)
3505   // It's what we cast the result to.
3506   const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3507   if (!tklass)  tklass = TypeKlassPtr::OBJECT;
3508   const TypeOopPtr* oop_type = tklass->as_instance_type();
3509 
3510   // Now generate allocation code
3511 
3512   // The entire memory state is needed for slow path of the allocation
3513   // since GC and deoptimization can happen.
3514   Node *mem = reset_memory();
3515   set_all_memory(mem); // Create new memory state
3516 
3517   AllocateNode* alloc = new AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3518                                          control(), mem, i_o(),
3519                                          size, klass_node,
3520                                          initial_slow_test);
3521 
3522   return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception);
3523 }
3524 
3525 //-------------------------------new_array-------------------------------------
3526 // helper for newarray, anewarray and vnewarray
3527 // The 'length' parameter is (obviously) the length of the array.
3528 // See comments on new_instance for the meaning of the other arguments.
3529 Node* GraphKit::new_array(Node* klass_node,     // array klass (maybe variable)
3530                           Node* length,         // number of array elements
3531                           int   nargs,          // number of arguments to push back for uncommon trap
3532                           Node* *return_size_val,
3533                           bool deoptimize_on_exception) {
3534   jint  layout_con = Klass::_lh_neutral_value;
3535   Node* layout_val = get_layout_helper(klass_node, layout_con);
3536   int   layout_is_con = (layout_val == NULL);
3537 
3538   if (!layout_is_con && !StressReflectiveCode &&
3539       !too_many_traps(Deoptimization::Reason_class_check)) {
3540     // This is a reflective array creation site.
3541     // Optimistically assume that it is a subtype of Object[],
3542     // so that we can fold up all the address arithmetic.
3543     layout_con = Klass::array_layout_helper(T_OBJECT);
3544     Node* cmp_lh = _gvn.transform( new CmpINode(layout_val, intcon(layout_con)) );
3545     Node* bol_lh = _gvn.transform( new BoolNode(cmp_lh, BoolTest::eq) );
3546     { BuildCutout unless(this, bol_lh, PROB_MAX);
3547       inc_sp(nargs);
3548       uncommon_trap(Deoptimization::Reason_class_check,
3549                     Deoptimization::Action_maybe_recompile);
3550     }
3551     layout_val = NULL;
3552     layout_is_con = true;
3553   }
3554 
3555   // Generate the initial go-slow test.  Make sure we do not overflow
3556   // if length is huge (near 2Gig) or negative!  We do not need
3557   // exact double-words here, just a close approximation of needed
3558   // double-words.  We can't add any offset or rounding bits, lest we
3559   // take a size -1 of bytes and make it positive.  Use an unsigned
3560   // compare, so negative sizes look hugely positive.
3561   int fast_size_limit = FastAllocateSizeLimit;
3562   if (layout_is_con) {
3563     assert(!StressReflectiveCode, "stress mode does not use these paths");
3564     // Increase the size limit if we have exact knowledge of array type.
3565     int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3566     fast_size_limit <<= (LogBytesPerLong - log2_esize);
3567   }
3568 
3569   Node* initial_slow_cmp  = _gvn.transform( new CmpUNode( length, intcon( fast_size_limit ) ) );
3570   Node* initial_slow_test = _gvn.transform( new BoolNode( initial_slow_cmp, BoolTest::gt ) );
3571 
3572   // --- Size Computation ---
3573   // array_size = round_to_heap(array_header + (length << elem_shift));
3574   // where round_to_heap(x) == round_to(x, MinObjAlignmentInBytes)
3575   // and round_to(x, y) == ((x + y-1) & ~(y-1))
3576   // The rounding mask is strength-reduced, if possible.
3577   int round_mask = MinObjAlignmentInBytes - 1;
3578   Node* header_size = NULL;
3579   int   header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3580   // (T_BYTE has the weakest alignment and size restrictions...)
3581   if (layout_is_con) {
3582     int       hsize  = Klass::layout_helper_header_size(layout_con);
3583     int       eshift = Klass::layout_helper_log2_element_size(layout_con);
3584     BasicType etype  = Klass::layout_helper_element_type(layout_con);
3585     if ((round_mask & ~right_n_bits(eshift)) == 0)
3586       round_mask = 0;  // strength-reduce it if it goes away completely
3587     // TODO re-enabled assert
3588   //  assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3589     assert(header_size_min <= hsize, "generic minimum is smallest");
3590     header_size_min = hsize;
3591     header_size = intcon(hsize + round_mask);
3592   } else {
3593     Node* hss   = intcon(Klass::_lh_header_size_shift);
3594     Node* hsm   = intcon(Klass::_lh_header_size_mask);
3595     Node* hsize = _gvn.transform( new URShiftINode(layout_val, hss) );
3596     hsize       = _gvn.transform( new AndINode(hsize, hsm) );
3597     Node* mask  = intcon(round_mask);
3598     header_size = _gvn.transform( new AddINode(hsize, mask) );
3599   }
3600 
3601   Node* elem_shift = NULL;
3602   if (layout_is_con) {
3603     int eshift = Klass::layout_helper_log2_element_size(layout_con);
3604     if (eshift != 0)
3605       elem_shift = intcon(eshift);
3606   } else {
3607     // There is no need to mask or shift this value.
3608     // The semantics of LShiftINode include an implicit mask to 0x1F.
3609     assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3610     elem_shift = layout_val;
3611   }
3612 
3613   // Transition to native address size for all offset calculations:
3614   Node* lengthx = ConvI2X(length);
3615   Node* headerx = ConvI2X(header_size);
3616 #ifdef _LP64
3617   { const TypeInt* tilen = _gvn.find_int_type(length);
3618     if (tilen != NULL && tilen->_lo < 0) {
3619       // Add a manual constraint to a positive range.  Cf. array_element_address.
3620       jint size_max = fast_size_limit;
3621       if (size_max > tilen->_hi)  size_max = tilen->_hi;
3622       const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin);
3623 
3624       // Only do a narrow I2L conversion if the range check passed.
3625       IfNode* iff = new IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
3626       _gvn.transform(iff);
3627       RegionNode* region = new RegionNode(3);
3628       _gvn.set_type(region, Type::CONTROL);
3629       lengthx = new PhiNode(region, TypeLong::LONG);
3630       _gvn.set_type(lengthx, TypeLong::LONG);
3631 
3632       // Range check passed. Use ConvI2L node with narrow type.
3633       Node* passed = IfFalse(iff);
3634       region->init_req(1, passed);
3635       // Make I2L conversion control dependent to prevent it from
3636       // floating above the range check during loop optimizations.
3637       lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed));
3638 
3639       // Range check failed. Use ConvI2L with wide type because length may be invalid.
3640       region->init_req(2, IfTrue(iff));
3641       lengthx->init_req(2, ConvI2X(length));
3642 
3643       set_control(region);
3644       record_for_igvn(region);
3645       record_for_igvn(lengthx);
3646     }
3647   }
3648 #endif
3649 
3650   // Combine header size (plus rounding) and body size.  Then round down.
3651   // This computation cannot overflow, because it is used only in two
3652   // places, one where the length is sharply limited, and the other
3653   // after a successful allocation.
3654   Node* abody = lengthx;
3655   if (elem_shift != NULL)
3656     abody     = _gvn.transform( new LShiftXNode(lengthx, elem_shift) );
3657   Node* size  = _gvn.transform( new AddXNode(headerx, abody) );
3658   if (round_mask != 0) {
3659     Node* mask = MakeConX(~round_mask);
3660     size       = _gvn.transform( new AndXNode(size, mask) );
3661   }
3662   // else if round_mask == 0, the size computation is self-rounding
3663 
3664   if (return_size_val != NULL) {
3665     // This is the size
3666     (*return_size_val) = size;
3667   }
3668 
3669   // Now generate allocation code
3670 
3671   // The entire memory state is needed for slow path of the allocation
3672   // since GC and deoptimization can happen.
3673   Node *mem = reset_memory();
3674   set_all_memory(mem); // Create new memory state
3675 
3676   if (initial_slow_test->is_Bool()) {
3677     // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3678     initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3679   }
3680 
3681   // Create the AllocateArrayNode and its result projections
3682   AllocateArrayNode* alloc
3683     = new AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
3684                             control(), mem, i_o(),
3685                             size, klass_node,
3686                             initial_slow_test,
3687                             length);
3688 
3689   // Cast to correct type.  Note that the klass_node may be constant or not,
3690   // and in the latter case the actual array type will be inexact also.
3691   // (This happens via a non-constant argument to inline_native_newArray.)
3692   // In any case, the value of klass_node provides the desired array type.
3693   const TypeInt* length_type = _gvn.find_int_type(length);
3694   const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3695   if (ary_type->isa_aryptr() && length_type != NULL) {
3696     // Try to get a better type than POS for the size
3697     ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3698   }
3699 
3700   Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception);
3701 
3702   // Cast length on remaining path to be as narrow as possible
3703   if (map()->find_edge(length) >= 0) {
3704     Node* ccast = alloc->make_ideal_length(ary_type, &_gvn);
3705     if (ccast != length) {
3706       _gvn.set_type_bottom(ccast);
3707       record_for_igvn(ccast);
3708       replace_in_map(length, ccast);
3709     }
3710   }
3711 
3712   const TypeAryPtr* ary_ptr = ary_type->isa_aryptr();
3713   ciKlass* elem_klass = ary_ptr != NULL ? ary_ptr->klass()->as_array_klass()->element_klass() : NULL;
3714   //if (layout_is_con && Klass::layout_helper_element_type(layout_con) == T_VALUETYPE) {
3715   if (elem_klass != NULL && elem_klass->is_valuetype()) {
3716     ciValueKlass* vk = elem_klass->as_value_klass();
3717     if (vk->flatten_array()) {
3718       // TODO
3719     } else {
3720       // TODO explain this and add asserts
3721       initialize_value_type_array(javaoop, length, elem_klass->as_value_klass(), nargs);
3722       InitializeNode* init = alloc->initialization();
3723       init->set_complete_with_arraycopy();
3724     }
3725   }
3726 
3727   return javaoop;
3728 }
3729 
3730 void GraphKit::initialize_value_type_array(Node* array, Node* length, ciValueKlass* vk, int nargs) {
3731   // Check for zero length
3732   Node* null_ctl = top();
3733   null_check_common(length, T_INT, false, &null_ctl, false);
3734   if (stopped()) {
3735     set_control(null_ctl); // Always zero
3736     return;
3737   }
3738 
3739   // Prepare for merging control and IO
3740   RegionNode* res_ctl = new RegionNode(3);
3741   res_ctl->init_req(1, null_ctl);
3742   gvn().set_type(res_ctl, Type::CONTROL);
3743   record_for_igvn(res_ctl);
3744   Node* res_io = PhiNode::make(res_ctl, i_o(), Type::ABIO);
3745   gvn().set_type(res_io, Type::ABIO);
3746   record_for_igvn(res_io);
3747 
3748   // TODO comment
3749   SafePointNode* loop_map = NULL;
3750   {
3751     PreserveJVMState pjvms(this);
3752     // Create default value type and store it to memory
3753     Node* oop = ValueTypeNode::make_default(gvn(), vk);
3754     oop = oop->as_ValueType()->store_to_memory(this);
3755 
3756     length = SubI(length, intcon(1));
3757     add_predicate(nargs);
3758     RegionNode* loop = new RegionNode(3);
3759     loop->init_req(1, control());
3760     gvn().set_type(loop, Type::CONTROL);
3761     record_for_igvn(loop);
3762 
3763     Node* index = new PhiNode(loop, TypeInt::INT);
3764     index->init_req(1, intcon(0));
3765     gvn().set_type(index, TypeInt::INT);
3766     record_for_igvn(index);
3767 
3768     // TODO explain why we need to capture all memory
3769     PhiNode* mem = new PhiNode(loop, Type::MEMORY, TypePtr::BOTTOM);
3770     mem->init_req(1, reset_memory());
3771     gvn().set_type(mem, Type::MEMORY);
3772     record_for_igvn(mem);
3773     set_control(loop);
3774     set_all_memory(mem);
3775     // Initialize array element
3776     Node* adr = array_element_address(array, index, T_OBJECT);
3777     const TypeOopPtr* elemtype = TypeValueTypePtr::make(TypePtr::NotNull, vk); // ary_type->is_aryptr()->elem()->make_oopptr();
3778     Node* store = store_oop_to_array(control(), array, adr, TypeAryPtr::OOPS, oop, elemtype, T_OBJECT, MemNode::release);
3779 
3780     IfNode* iff = create_and_map_if(control(), Bool(CmpI(index, length), BoolTest::lt), PROB_FAIR, COUNT_UNKNOWN);
3781     loop->init_req(2, IfTrue(iff));
3782     mem->init_req(2, merged_memory());
3783     index->init_req(2, AddI(index, intcon(1)));
3784 
3785     res_ctl->init_req(2, IfFalse(iff));
3786     res_io->set_req(2, i_o());
3787     loop_map = stop();
3788   }
3789   // Set merged control, IO and memory
3790   set_control(res_ctl);
3791   set_i_o(res_io);
3792   merge_memory(loop_map->merged_memory(), res_ctl, 2);
3793 }
3794 
3795 // The following "Ideal_foo" functions are placed here because they recognize
3796 // the graph shapes created by the functions immediately above.
3797 
3798 //---------------------------Ideal_allocation----------------------------------
3799 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3800 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) {
3801   if (ptr == NULL) {     // reduce dumb test in callers
3802     return NULL;
3803   }
3804   if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
3805     ptr = ptr->in(1);
3806     if (ptr == NULL) return NULL;
3807   }
3808   // Return NULL for allocations with several casts:
3809   //   j.l.reflect.Array.newInstance(jobject, jint)
3810   //   Object.clone()
3811   // to keep more precise type from last cast.
3812   if (ptr->is_Proj()) {
3813     Node* allo = ptr->in(0);
3814     if (allo != NULL && allo->is_Allocate()) {
3815       return allo->as_Allocate();
3816     }
3817   }
3818   // Report failure to match.
3819   return NULL;
3820 }
3821 
3822 // Fancy version which also strips off an offset (and reports it to caller).
3823 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase,
3824                                              intptr_t& offset) {
3825   Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
3826   if (base == NULL)  return NULL;
3827   return Ideal_allocation(base, phase);
3828 }
3829 
3830 // Trace Initialize <- Proj[Parm] <- Allocate
3831 AllocateNode* InitializeNode::allocation() {
3832   Node* rawoop = in(InitializeNode::RawAddress);
3833   if (rawoop->is_Proj()) {
3834     Node* alloc = rawoop->in(0);
3835     if (alloc->is_Allocate()) {
3836       return alloc->as_Allocate();
3837     }
3838   }
3839   return NULL;
3840 }
3841 
3842 // Trace Allocate -> Proj[Parm] -> Initialize
3843 InitializeNode* AllocateNode::initialization() {
3844   ProjNode* rawoop = proj_out(AllocateNode::RawAddress);
3845   if (rawoop == NULL)  return NULL;
3846   for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3847     Node* init = rawoop->fast_out(i);
3848     if (init->is_Initialize()) {
3849       assert(init->as_Initialize()->allocation() == this, "2-way link");
3850       return init->as_Initialize();
3851     }
3852   }
3853   return NULL;
3854 }
3855 
3856 //----------------------------- loop predicates ---------------------------
3857 
3858 //------------------------------add_predicate_impl----------------------------
3859 void GraphKit::add_predicate_impl(Deoptimization::DeoptReason reason, int nargs) {
3860   // Too many traps seen?
3861   if (too_many_traps(reason)) {
3862 #ifdef ASSERT
3863     if (TraceLoopPredicate) {
3864       int tc = C->trap_count(reason);
3865       tty->print("too many traps=%s tcount=%d in ",
3866                     Deoptimization::trap_reason_name(reason), tc);
3867       method()->print(); // which method has too many predicate traps
3868       tty->cr();
3869     }
3870 #endif
3871     // We cannot afford to take more traps here,
3872     // do not generate predicate.
3873     return;
3874   }
3875 
3876   Node *cont    = _gvn.intcon(1);
3877   Node* opq     = _gvn.transform(new Opaque1Node(C, cont));
3878   Node *bol     = _gvn.transform(new Conv2BNode(opq));
3879   IfNode* iff   = create_and_map_if(control(), bol, PROB_MAX, COUNT_UNKNOWN);
3880   Node* iffalse = _gvn.transform(new IfFalseNode(iff));
3881   C->add_predicate_opaq(opq);
3882   {
3883     PreserveJVMState pjvms(this);
3884     set_control(iffalse);
3885     inc_sp(nargs);
3886     uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
3887   }
3888   Node* iftrue = _gvn.transform(new IfTrueNode(iff));
3889   set_control(iftrue);
3890 }
3891 
3892 //------------------------------add_predicate---------------------------------
3893 void GraphKit::add_predicate(int nargs) {
3894   if (UseLoopPredicate) {
3895     add_predicate_impl(Deoptimization::Reason_predicate, nargs);
3896   }
3897   // loop's limit check predicate should be near the loop.
3898   if (LoopLimitCheck) {
3899     add_predicate_impl(Deoptimization::Reason_loop_limit_check, nargs);
3900   }
3901 }
3902 
3903 //----------------------------- store barriers ----------------------------
3904 #define __ ideal.
3905 
3906 void GraphKit::sync_kit(IdealKit& ideal) {
3907   set_all_memory(__ merged_memory());
3908   set_i_o(__ i_o());
3909   set_control(__ ctrl());
3910 }
3911 
3912 void GraphKit::final_sync(IdealKit& ideal) {
3913   // Final sync IdealKit and graphKit.
3914   sync_kit(ideal);
3915 }
3916 
3917 Node* GraphKit::byte_map_base_node() {
3918   // Get base of card map
3919   CardTableModRefBS* ct =
3920     barrier_set_cast<CardTableModRefBS>(Universe::heap()->barrier_set());
3921   assert(sizeof(*ct->byte_map_base) == sizeof(jbyte), "adjust users of this code");
3922   if (ct->byte_map_base != NULL) {
3923     return makecon(TypeRawPtr::make((address)ct->byte_map_base));
3924   } else {
3925     return null();
3926   }
3927 }
3928 
3929 // vanilla/CMS post barrier
3930 // Insert a write-barrier store.  This is to let generational GC work; we have
3931 // to flag all oop-stores before the next GC point.
3932 void GraphKit::write_barrier_post(Node* oop_store,
3933                                   Node* obj,
3934                                   Node* adr,
3935                                   uint  adr_idx,
3936                                   Node* val,
3937                                   bool use_precise) {
3938   // No store check needed if we're storing a NULL or an old object
3939   // (latter case is probably a string constant). The concurrent
3940   // mark sweep garbage collector, however, needs to have all nonNull
3941   // oop updates flagged via card-marks.
3942   if (val != NULL && val->is_Con()) {
3943     // must be either an oop or NULL
3944     const Type* t = val->bottom_type();
3945     if (t == TypePtr::NULL_PTR || t == Type::TOP)
3946       // stores of null never (?) need barriers
3947       return;
3948   }
3949 
3950   if (use_ReduceInitialCardMarks()
3951       && obj == just_allocated_object(control())) {
3952     // We can skip marks on a freshly-allocated object in Eden.
3953     // Keep this code in sync with new_store_pre_barrier() in runtime.cpp.
3954     // That routine informs GC to take appropriate compensating steps,
3955     // upon a slow-path allocation, so as to make this card-mark
3956     // elision safe.
3957     return;
3958   }
3959 
3960   if (!use_precise) {
3961     // All card marks for a (non-array) instance are in one place:
3962     adr = obj;
3963   }
3964   // (Else it's an array (or unknown), and we want more precise card marks.)
3965   assert(adr != NULL, "");
3966 
3967   IdealKit ideal(this, true);
3968 
3969   // Convert the pointer to an int prior to doing math on it
3970   Node* cast = __ CastPX(__ ctrl(), adr);
3971 
3972   // Divide by card size
3973   assert(Universe::heap()->barrier_set()->is_a(BarrierSet::CardTableModRef),
3974          "Only one we handle so far.");
3975   Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3976 
3977   // Combine card table base and card offset
3978   Node* card_adr = __ AddP(__ top(), byte_map_base_node(), card_offset );
3979 
3980   // Get the alias_index for raw card-mark memory
3981   int adr_type = Compile::AliasIdxRaw;
3982   Node*   zero = __ ConI(0); // Dirty card value
3983   BasicType bt = T_BYTE;
3984 
3985   if (UseConcMarkSweepGC && UseCondCardMark) {
3986     insert_store_load_for_barrier();
3987     __ sync_kit(this);
3988   }
3989 
3990   if (UseCondCardMark) {
3991     // The classic GC reference write barrier is typically implemented
3992     // as a store into the global card mark table.  Unfortunately
3993     // unconditional stores can result in false sharing and excessive
3994     // coherence traffic as well as false transactional aborts.
3995     // UseCondCardMark enables MP "polite" conditional card mark
3996     // stores.  In theory we could relax the load from ctrl() to
3997     // no_ctrl, but that doesn't buy much latitude.
3998     Node* card_val = __ load( __ ctrl(), card_adr, TypeInt::BYTE, bt, adr_type);
3999     __ if_then(card_val, BoolTest::ne, zero);
4000   }
4001 
4002   // Smash zero into card
4003   if( !UseConcMarkSweepGC ) {
4004     __ store(__ ctrl(), card_adr, zero, bt, adr_type, MemNode::unordered);
4005   } else {
4006     // Specialized path for CM store barrier
4007     __ storeCM(__ ctrl(), card_adr, zero, oop_store, adr_idx, bt, adr_type);
4008   }
4009 
4010   if (UseCondCardMark) {
4011     __ end_if();
4012   }
4013 
4014   // Final sync IdealKit and GraphKit.
4015   final_sync(ideal);
4016 }
4017 /*
4018  * Determine if the G1 pre-barrier can be removed. The pre-barrier is
4019  * required by SATB to make sure all objects live at the start of the
4020  * marking are kept alive, all reference updates need to any previous
4021  * reference stored before writing.
4022  *
4023  * If the previous value is NULL there is no need to save the old value.
4024  * References that are NULL are filtered during runtime by the barrier
4025  * code to avoid unnecessary queuing.
4026  *
4027  * However in the case of newly allocated objects it might be possible to
4028  * prove that the reference about to be overwritten is NULL during compile
4029  * time and avoid adding the barrier code completely.
4030  *
4031  * The compiler needs to determine that the object in which a field is about
4032  * to be written is newly allocated, and that no prior store to the same field
4033  * has happened since the allocation.
4034  *
4035  * Returns true if the pre-barrier can be removed
4036  */
4037 bool GraphKit::g1_can_remove_pre_barrier(PhaseTransform* phase, Node* adr,
4038                                          BasicType bt, uint adr_idx) {
4039   intptr_t offset = 0;
4040   Node* base = AddPNode::Ideal_base_and_offset(adr, phase, offset);
4041   AllocateNode* alloc = AllocateNode::Ideal_allocation(base, phase);
4042 
4043   if (offset == Type::OffsetBot) {
4044     return false; // cannot unalias unless there are precise offsets
4045   }
4046 
4047   if (alloc == NULL) {
4048     return false; // No allocation found
4049   }
4050 
4051   intptr_t size_in_bytes = type2aelembytes(bt);
4052 
4053   Node* mem = memory(adr_idx); // start searching here...
4054 
4055   for (int cnt = 0; cnt < 50; cnt++) {
4056 
4057     if (mem->is_Store()) {
4058 
4059       Node* st_adr = mem->in(MemNode::Address);
4060       intptr_t st_offset = 0;
4061       Node* st_base = AddPNode::Ideal_base_and_offset(st_adr, phase, st_offset);
4062 
4063       if (st_base == NULL) {
4064         break; // inscrutable pointer
4065       }
4066 
4067       // Break we have found a store with same base and offset as ours so break
4068       if (st_base == base && st_offset == offset) {
4069         break;
4070       }
4071 
4072       if (st_offset != offset && st_offset != Type::OffsetBot) {
4073         const int MAX_STORE = BytesPerLong;
4074         if (st_offset >= offset + size_in_bytes ||
4075             st_offset <= offset - MAX_STORE ||
4076             st_offset <= offset - mem->as_Store()->memory_size()) {
4077           // Success:  The offsets are provably independent.
4078           // (You may ask, why not just test st_offset != offset and be done?
4079           // The answer is that stores of different sizes can co-exist
4080           // in the same sequence of RawMem effects.  We sometimes initialize
4081           // a whole 'tile' of array elements with a single jint or jlong.)
4082           mem = mem->in(MemNode::Memory);
4083           continue; // advance through independent store memory
4084         }
4085       }
4086 
4087       if (st_base != base
4088           && MemNode::detect_ptr_independence(base, alloc, st_base,
4089                                               AllocateNode::Ideal_allocation(st_base, phase),
4090                                               phase)) {
4091         // Success:  The bases are provably independent.
4092         mem = mem->in(MemNode::Memory);
4093         continue; // advance through independent store memory
4094       }
4095     } else if (mem->is_Proj() && mem->in(0)->is_Initialize()) {
4096 
4097       InitializeNode* st_init = mem->in(0)->as_Initialize();
4098       AllocateNode* st_alloc = st_init->allocation();
4099 
4100       // Make sure that we are looking at the same allocation site.
4101       // The alloc variable is guaranteed to not be null here from earlier check.
4102       if (alloc == st_alloc) {
4103         // Check that the initialization is storing NULL so that no previous store
4104         // has been moved up and directly write a reference
4105         Node* captured_store = st_init->find_captured_store(offset,
4106                                                             type2aelembytes(T_OBJECT),
4107                                                             phase);
4108         if (captured_store == NULL || captured_store == st_init->zero_memory()) {
4109           return true;
4110         }
4111       }
4112     }
4113 
4114     // Unless there is an explicit 'continue', we must bail out here,
4115     // because 'mem' is an inscrutable memory state (e.g., a call).
4116     break;
4117   }
4118 
4119   return false;
4120 }
4121 
4122 // G1 pre/post barriers
4123 void GraphKit::g1_write_barrier_pre(bool do_load,
4124                                     Node* obj,
4125                                     Node* adr,
4126                                     uint alias_idx,
4127                                     Node* val,
4128                                     const TypeOopPtr* val_type,
4129                                     Node* pre_val,
4130                                     BasicType bt) {
4131 
4132   // Some sanity checks
4133   // Note: val is unused in this routine.
4134 
4135   if (do_load) {
4136     // We need to generate the load of the previous value
4137     assert(obj != NULL, "must have a base");
4138     assert(adr != NULL, "where are loading from?");
4139     assert(pre_val == NULL, "loaded already?");
4140     assert(val_type != NULL, "need a type");
4141 
4142     if (use_ReduceInitialCardMarks()
4143         && g1_can_remove_pre_barrier(&_gvn, adr, bt, alias_idx)) {
4144       return;
4145     }
4146 
4147   } else {
4148     // In this case both val_type and alias_idx are unused.
4149     assert(pre_val != NULL, "must be loaded already");
4150     // Nothing to be done if pre_val is null.
4151     if (pre_val->bottom_type() == TypePtr::NULL_PTR) return;
4152     assert(pre_val->bottom_type()->basic_type() == T_OBJECT, "or we shouldn't be here");
4153   }
4154   assert(bt == T_OBJECT || bt == T_VALUETYPE, "or we shouldn't be here");
4155 
4156   IdealKit ideal(this, true);
4157 
4158   Node* tls = __ thread(); // ThreadLocalStorage
4159 
4160   Node* no_ctrl = NULL;
4161   Node* no_base = __ top();
4162   Node* zero  = __ ConI(0);
4163   Node* zeroX = __ ConX(0);
4164 
4165   float likely  = PROB_LIKELY(0.999);
4166   float unlikely  = PROB_UNLIKELY(0.999);
4167 
4168   BasicType active_type = in_bytes(SATBMarkQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE;
4169   assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 4 || in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "flag width");
4170 
4171   // Offsets into the thread
4172   const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() +  // 648
4173                                           SATBMarkQueue::byte_offset_of_active());
4174   const int index_offset   = in_bytes(JavaThread::satb_mark_queue_offset() +  // 656
4175                                           SATBMarkQueue::byte_offset_of_index());
4176   const int buffer_offset  = in_bytes(JavaThread::satb_mark_queue_offset() +  // 652
4177                                           SATBMarkQueue::byte_offset_of_buf());
4178 
4179   // Now the actual pointers into the thread
4180   Node* marking_adr = __ AddP(no_base, tls, __ ConX(marking_offset));
4181   Node* buffer_adr  = __ AddP(no_base, tls, __ ConX(buffer_offset));
4182   Node* index_adr   = __ AddP(no_base, tls, __ ConX(index_offset));
4183 
4184   // Now some of the values
4185   Node* marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw);
4186 
4187   // if (!marking)
4188   __ if_then(marking, BoolTest::ne, zero, unlikely); {
4189     BasicType index_bt = TypeX_X->basic_type();
4190     assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading G1 SATBMarkQueue::_index with wrong size.");
4191     Node* index   = __ load(__ ctrl(), index_adr, TypeX_X, index_bt, Compile::AliasIdxRaw);
4192 
4193     if (do_load) {
4194       // load original value
4195       // alias_idx correct??
4196       pre_val = __ load(__ ctrl(), adr, val_type, bt, alias_idx);
4197     }
4198 
4199     // if (pre_val != NULL)
4200     __ if_then(pre_val, BoolTest::ne, null()); {
4201       Node* buffer  = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
4202 
4203       // is the queue for this thread full?
4204       __ if_then(index, BoolTest::ne, zeroX, likely); {
4205 
4206         // decrement the index
4207         Node* next_index = _gvn.transform(new SubXNode(index, __ ConX(sizeof(intptr_t))));
4208 
4209         // Now get the buffer location we will log the previous value into and store it
4210         Node *log_addr = __ AddP(no_base, buffer, next_index);
4211         __ store(__ ctrl(), log_addr, pre_val, T_OBJECT, Compile::AliasIdxRaw, MemNode::unordered);
4212         // update the index
4213         __ store(__ ctrl(), index_adr, next_index, index_bt, Compile::AliasIdxRaw, MemNode::unordered);
4214 
4215       } __ else_(); {
4216 
4217         // logging buffer is full, call the runtime
4218         const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type();
4219         __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", pre_val, tls);
4220       } __ end_if();  // (!index)
4221     } __ end_if();  // (pre_val != NULL)
4222   } __ end_if();  // (!marking)
4223 
4224   // Final sync IdealKit and GraphKit.
4225   final_sync(ideal);
4226 }
4227 
4228 /*
4229  * G1 similar to any GC with a Young Generation requires a way to keep track of
4230  * references from Old Generation to Young Generation to make sure all live
4231  * objects are found. G1 also requires to keep track of object references
4232  * between different regions to enable evacuation of old regions, which is done
4233  * as part of mixed collections. References are tracked in remembered sets and
4234  * is continuously updated as reference are written to with the help of the
4235  * post-barrier.
4236  *
4237  * To reduce the number of updates to the remembered set the post-barrier
4238  * filters updates to fields in objects located in the Young Generation,
4239  * the same region as the reference, when the NULL is being written or
4240  * if the card is already marked as dirty by an earlier write.
4241  *
4242  * Under certain circumstances it is possible to avoid generating the
4243  * post-barrier completely if it is possible during compile time to prove
4244  * the object is newly allocated and that no safepoint exists between the
4245  * allocation and the store.
4246  *
4247  * In the case of slow allocation the allocation code must handle the barrier
4248  * as part of the allocation in the case the allocated object is not located
4249  * in the nursery, this would happen for humongous objects. This is similar to
4250  * how CMS is required to handle this case, see the comments for the method
4251  * CollectedHeap::new_store_pre_barrier and OptoRuntime::new_store_pre_barrier.
4252  * A deferred card mark is required for these objects and handled in the above
4253  * mentioned methods.
4254  *
4255  * Returns true if the post barrier can be removed
4256  */
4257 bool GraphKit::g1_can_remove_post_barrier(PhaseTransform* phase, Node* store,
4258                                           Node* adr) {
4259   intptr_t      offset = 0;
4260   Node*         base   = AddPNode::Ideal_base_and_offset(adr, phase, offset);
4261   AllocateNode* alloc  = AllocateNode::Ideal_allocation(base, phase);
4262 
4263   if (offset == Type::OffsetBot) {
4264     return false; // cannot unalias unless there are precise offsets
4265   }
4266 
4267   if (alloc == NULL) {
4268      return false; // No allocation found
4269   }
4270 
4271   // Start search from Store node
4272   Node* mem = store->in(MemNode::Control);
4273   if (mem->is_Proj() && mem->in(0)->is_Initialize()) {
4274 
4275     InitializeNode* st_init = mem->in(0)->as_Initialize();
4276     AllocateNode*  st_alloc = st_init->allocation();
4277 
4278     // Make sure we are looking at the same allocation
4279     if (alloc == st_alloc) {
4280       return true;
4281     }
4282   }
4283 
4284   return false;
4285 }
4286 
4287 //
4288 // Update the card table and add card address to the queue
4289 //
4290 void GraphKit::g1_mark_card(IdealKit& ideal,
4291                             Node* card_adr,
4292                             Node* oop_store,
4293                             uint oop_alias_idx,
4294                             Node* index,
4295                             Node* index_adr,
4296                             Node* buffer,
4297                             const TypeFunc* tf) {
4298 
4299   Node* zero  = __ ConI(0);
4300   Node* zeroX = __ ConX(0);
4301   Node* no_base = __ top();
4302   BasicType card_bt = T_BYTE;
4303   // Smash zero into card. MUST BE ORDERED WRT TO STORE
4304   __ storeCM(__ ctrl(), card_adr, zero, oop_store, oop_alias_idx, card_bt, Compile::AliasIdxRaw);
4305 
4306   //  Now do the queue work
4307   __ if_then(index, BoolTest::ne, zeroX); {
4308 
4309     Node* next_index = _gvn.transform(new SubXNode(index, __ ConX(sizeof(intptr_t))));
4310     Node* log_addr = __ AddP(no_base, buffer, next_index);
4311 
4312     // Order, see storeCM.
4313     __ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
4314     __ store(__ ctrl(), index_adr, next_index, TypeX_X->basic_type(), Compile::AliasIdxRaw, MemNode::unordered);
4315 
4316   } __ else_(); {
4317     __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread());
4318   } __ end_if();
4319 
4320 }
4321 
4322 void GraphKit::g1_write_barrier_post(Node* oop_store,
4323                                      Node* obj,
4324                                      Node* adr,
4325                                      uint alias_idx,
4326                                      Node* val,
4327                                      BasicType bt,
4328                                      bool use_precise) {
4329   // If we are writing a NULL then we need no post barrier
4330 
4331   if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) {
4332     // Must be NULL
4333     const Type* t = val->bottom_type();
4334     assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL");
4335     // No post barrier if writing NULLx
4336     return;
4337   }
4338 
4339   if (use_ReduceInitialCardMarks() && obj == just_allocated_object(control())) {
4340     // We can skip marks on a freshly-allocated object in Eden.
4341     // Keep this code in sync with new_store_pre_barrier() in runtime.cpp.
4342     // That routine informs GC to take appropriate compensating steps,
4343     // upon a slow-path allocation, so as to make this card-mark
4344     // elision safe.
4345     return;
4346   }
4347 
4348   if (use_ReduceInitialCardMarks()
4349       && g1_can_remove_post_barrier(&_gvn, oop_store, adr)) {
4350     return;
4351   }
4352 
4353   if (!use_precise) {
4354     // All card marks for a (non-array) instance are in one place:
4355     adr = obj;
4356   }
4357   // (Else it's an array (or unknown), and we want more precise card marks.)
4358   assert(adr != NULL, "");
4359 
4360   IdealKit ideal(this, true);
4361 
4362   Node* tls = __ thread(); // ThreadLocalStorage
4363 
4364   Node* no_base = __ top();
4365   float likely  = PROB_LIKELY(0.999);
4366   float unlikely  = PROB_UNLIKELY(0.999);
4367   Node* young_card = __ ConI((jint)G1SATBCardTableModRefBS::g1_young_card_val());
4368   Node* dirty_card = __ ConI((jint)CardTableModRefBS::dirty_card_val());
4369   Node* zeroX = __ ConX(0);
4370 
4371   // Get the alias_index for raw card-mark memory
4372   const TypePtr* card_type = TypeRawPtr::BOTTOM;
4373 
4374   const TypeFunc *tf = OptoRuntime::g1_wb_post_Type();
4375 
4376   // Offsets into the thread
4377   const int index_offset  = in_bytes(JavaThread::dirty_card_queue_offset() +
4378                                      DirtyCardQueue::byte_offset_of_index());
4379   const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
4380                                      DirtyCardQueue::byte_offset_of_buf());
4381 
4382   // Pointers into the thread
4383 
4384   Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
4385   Node* index_adr =  __ AddP(no_base, tls, __ ConX(index_offset));
4386 
4387   // Now some values
4388   // Use ctrl to avoid hoisting these values past a safepoint, which could
4389   // potentially reset these fields in the JavaThread.
4390   Node* index  = __ load(__ ctrl(), index_adr, TypeX_X, TypeX_X->basic_type(), Compile::AliasIdxRaw);
4391   Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
4392 
4393   // Convert the store obj pointer to an int prior to doing math on it
4394   // Must use ctrl to prevent "integerized oop" existing across safepoint
4395   Node* cast =  __ CastPX(__ ctrl(), adr);
4396 
4397   // Divide pointer by card size
4398   Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
4399 
4400   // Combine card table base and card offset
4401   Node* card_adr = __ AddP(no_base, byte_map_base_node(), card_offset );
4402 
4403   // If we know the value being stored does it cross regions?
4404 
4405   if (val != NULL) {
4406     // Does the store cause us to cross regions?
4407 
4408     // Should be able to do an unsigned compare of region_size instead of
4409     // and extra shift. Do we have an unsigned compare??
4410     // Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes);
4411     Node* xor_res =  __ URShiftX ( __ XorX( cast,  __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes));
4412 
4413     // if (xor_res == 0) same region so skip
4414     __ if_then(xor_res, BoolTest::ne, zeroX); {
4415 
4416       // No barrier if we are storing a NULL
4417       __ if_then(val, BoolTest::ne, null(), unlikely); {
4418 
4419         // Ok must mark the card if not already dirty
4420 
4421         // load the original value of the card
4422         Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4423 
4424         __ if_then(card_val, BoolTest::ne, young_card); {
4425           sync_kit(ideal);
4426           insert_store_load_for_barrier();
4427           __ sync_kit(this);
4428 
4429           Node* card_val_reload = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4430           __ if_then(card_val_reload, BoolTest::ne, dirty_card); {
4431             g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4432           } __ end_if();
4433         } __ end_if();
4434       } __ end_if();
4435     } __ end_if();
4436   } else {
4437     // Object.clone() instrinsic uses this path.
4438     g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4439   }
4440 
4441   // Final sync IdealKit and GraphKit.
4442   final_sync(ideal);
4443 }
4444 #undef __
4445 
4446 
4447 Node* GraphKit::load_String_length(Node* ctrl, Node* str) {
4448   Node* len = load_array_length(load_String_value(ctrl, str));
4449   Node* coder = load_String_coder(ctrl, str);
4450   // Divide length by 2 if coder is UTF16
4451   return _gvn.transform(new RShiftINode(len, coder));
4452 }
4453 
4454 Node* GraphKit::load_String_value(Node* ctrl, Node* str) {
4455   int value_offset = java_lang_String::value_offset_in_bytes();
4456   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4457                                                      false, NULL, 0);
4458   const TypePtr* value_field_type = string_type->add_offset(value_offset);
4459   const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
4460                                                   TypeAry::make(TypeInt::BYTE, TypeInt::POS),
4461                                                   ciTypeArrayKlass::make(T_BYTE), true, 0);
4462   int value_field_idx = C->get_alias_index(value_field_type);
4463   Node* load = make_load(ctrl, basic_plus_adr(str, str, value_offset),
4464                          value_type, T_OBJECT, value_field_idx, MemNode::unordered);
4465   // String.value field is known to be @Stable.
4466   if (UseImplicitStableValues) {
4467     load = cast_array_to_stable(load, value_type);
4468   }
4469   return load;
4470 }
4471 
4472 Node* GraphKit::load_String_coder(Node* ctrl, Node* str) {
4473   if (java_lang_String::has_coder_field()) {
4474     if (!CompactStrings) {
4475       return intcon(java_lang_String::CODER_UTF16);
4476     }
4477     int coder_offset = java_lang_String::coder_offset_in_bytes();
4478     const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4479                                                        false, NULL, 0);
4480     const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4481     int coder_field_idx = C->get_alias_index(coder_field_type);
4482     return make_load(ctrl, basic_plus_adr(str, str, coder_offset),
4483                      TypeInt::BYTE, T_BYTE, coder_field_idx, MemNode::unordered);
4484   } else {
4485     return intcon(0); // false
4486   }
4487 }
4488 
4489 void GraphKit::store_String_value(Node* ctrl, Node* str, Node* value) {
4490   int value_offset = java_lang_String::value_offset_in_bytes();
4491   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4492                                                      false, NULL, 0);
4493   const TypePtr* value_field_type = string_type->add_offset(value_offset);
4494   store_oop_to_object(ctrl, str,  basic_plus_adr(str, value_offset), value_field_type,
4495       value, TypeAryPtr::BYTES, T_OBJECT, MemNode::unordered);
4496 }
4497 
4498 void GraphKit::store_String_coder(Node* ctrl, Node* str, Node* value) {
4499   int coder_offset = java_lang_String::coder_offset_in_bytes();
4500   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4501                                                      false, NULL, 0);
4502   const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4503   int coder_field_idx = C->get_alias_index(coder_field_type);
4504   store_to_memory(ctrl, basic_plus_adr(str, coder_offset),
4505                   value, T_BYTE, coder_field_idx, MemNode::unordered);
4506 }
4507 
4508 // Capture src and dst memory state with a MergeMemNode
4509 Node* GraphKit::capture_memory(const TypePtr* src_type, const TypePtr* dst_type) {
4510   if (src_type == dst_type) {
4511     // Types are equal, we don't need a MergeMemNode
4512     return memory(src_type);
4513   }
4514   MergeMemNode* merge = MergeMemNode::make(map()->memory());
4515   record_for_igvn(merge); // fold it up later, if possible
4516   int src_idx = C->get_alias_index(src_type);
4517   int dst_idx = C->get_alias_index(dst_type);
4518   merge->set_memory_at(src_idx, memory(src_idx));
4519   merge->set_memory_at(dst_idx, memory(dst_idx));
4520   return merge;
4521 }
4522 
4523 Node* GraphKit::compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count) {
4524   assert(Matcher::match_rule_supported(Op_StrCompressedCopy), "Intrinsic not supported");
4525   assert(src_type == TypeAryPtr::BYTES || src_type == TypeAryPtr::CHARS, "invalid source type");
4526   // If input and output memory types differ, capture both states to preserve
4527   // the dependency between preceding and subsequent loads/stores.
4528   // For example, the following program:
4529   //  StoreB
4530   //  compress_string
4531   //  LoadB
4532   // has this memory graph (use->def):
4533   //  LoadB -> compress_string -> CharMem
4534   //             ... -> StoreB -> ByteMem
4535   // The intrinsic hides the dependency between LoadB and StoreB, causing
4536   // the load to read from memory not containing the result of the StoreB.
4537   // The correct memory graph should look like this:
4538   //  LoadB -> compress_string -> MergeMem(CharMem, StoreB(ByteMem))
4539   Node* mem = capture_memory(src_type, TypeAryPtr::BYTES);
4540   StrCompressedCopyNode* str = new StrCompressedCopyNode(control(), mem, src, dst, count);
4541   Node* res_mem = _gvn.transform(new SCMemProjNode(str));
4542   set_memory(res_mem, TypeAryPtr::BYTES);
4543   return str;
4544 }
4545 
4546 void GraphKit::inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count) {
4547   assert(Matcher::match_rule_supported(Op_StrInflatedCopy), "Intrinsic not supported");
4548   assert(dst_type == TypeAryPtr::BYTES || dst_type == TypeAryPtr::CHARS, "invalid dest type");
4549   // Capture src and dst memory (see comment in 'compress_string').
4550   Node* mem = capture_memory(TypeAryPtr::BYTES, dst_type);
4551   StrInflatedCopyNode* str = new StrInflatedCopyNode(control(), mem, src, dst, count);
4552   set_memory(_gvn.transform(str), dst_type);
4553 }
4554 
4555 void GraphKit::inflate_string_slow(Node* src, Node* dst, Node* start, Node* count) {
4556   /**
4557    * int i_char = start;
4558    * for (int i_byte = 0; i_byte < count; i_byte++) {
4559    *   dst[i_char++] = (char)(src[i_byte] & 0xff);
4560    * }
4561    */
4562   add_predicate();
4563   RegionNode* head = new RegionNode(3);
4564   head->init_req(1, control());
4565   gvn().set_type(head, Type::CONTROL);
4566   record_for_igvn(head);
4567 
4568   Node* i_byte = new PhiNode(head, TypeInt::INT);
4569   i_byte->init_req(1, intcon(0));
4570   gvn().set_type(i_byte, TypeInt::INT);
4571   record_for_igvn(i_byte);
4572 
4573   Node* i_char = new PhiNode(head, TypeInt::INT);
4574   i_char->init_req(1, start);
4575   gvn().set_type(i_char, TypeInt::INT);
4576   record_for_igvn(i_char);
4577 
4578   Node* mem = PhiNode::make(head, memory(TypeAryPtr::BYTES), Type::MEMORY, TypeAryPtr::BYTES);
4579   gvn().set_type(mem, Type::MEMORY);
4580   record_for_igvn(mem);
4581   set_control(head);
4582   set_memory(mem, TypeAryPtr::BYTES);
4583   Node* ch = load_array_element(control(), src, i_byte, TypeAryPtr::BYTES);
4584   Node* st = store_to_memory(control(), array_element_address(dst, i_char, T_BYTE),
4585                              AndI(ch, intcon(0xff)), T_CHAR, TypeAryPtr::BYTES, MemNode::unordered,
4586                              false, false, true /* mismatched */);
4587 
4588   IfNode* iff = create_and_map_if(head, Bool(CmpI(i_byte, count), BoolTest::lt), PROB_FAIR, COUNT_UNKNOWN);
4589   head->init_req(2, IfTrue(iff));
4590   mem->init_req(2, st);
4591   i_byte->init_req(2, AddI(i_byte, intcon(1)));
4592   i_char->init_req(2, AddI(i_char, intcon(2)));
4593 
4594   set_control(IfFalse(iff));
4595   set_memory(st, TypeAryPtr::BYTES);
4596 }
4597 
4598 Node* GraphKit::cast_array_to_stable(Node* ary, const TypeAryPtr* ary_type) {
4599   // Reify the property as a CastPP node in Ideal graph to comply with monotonicity
4600   // assumption of CCP analysis.
4601   return _gvn.transform(new CastPPNode(ary, ary_type->cast_to_stable(true)));
4602 }