1 /*
   2  * Copyright (c) 2001, 2018, 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 "ci/ciUtilities.hpp"
  27 #include "compiler/compileLog.hpp"
  28 #include "gc/shared/barrierSet.hpp"
  29 #include "gc/shared/c2/barrierSetC2.hpp"
  30 #include "interpreter/interpreter.hpp"
  31 #include "memory/resourceArea.hpp"
  32 #include "opto/addnode.hpp"
  33 #include "opto/castnode.hpp"
  34 #include "opto/convertnode.hpp"
  35 #include "opto/graphKit.hpp"
  36 #include "opto/idealKit.hpp"
  37 #include "opto/intrinsicnode.hpp"
  38 #include "opto/locknode.hpp"
  39 #include "opto/machnode.hpp"
  40 #include "opto/opaquenode.hpp"
  41 #include "opto/parse.hpp"
  42 #include "opto/rootnode.hpp"
  43 #include "opto/runtime.hpp"
  44 #include "runtime/deoptimization.hpp"
  45 #include "runtime/sharedRuntime.hpp"
  46 #include "utilities/macros.hpp"
  47 #if INCLUDE_SHENANDOAHGC
  48 #include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
  49 #endif
  50 
  51 //----------------------------GraphKit-----------------------------------------
  52 // Main utility constructor.
  53 GraphKit::GraphKit(JVMState* jvms)
  54   : Phase(Phase::Parser),
  55     _env(C->env()),
  56     _gvn(*C->initial_gvn()),
  57     _barrier_set(BarrierSet::barrier_set()->barrier_set_c2())
  58 {
  59   _exceptions = jvms->map()->next_exception();
  60   if (_exceptions != NULL)  jvms->map()->set_next_exception(NULL);
  61   set_jvms(jvms);
  62 }
  63 
  64 // Private constructor for parser.
  65 GraphKit::GraphKit()
  66   : Phase(Phase::Parser),
  67     _env(C->env()),
  68     _gvn(*C->initial_gvn()),
  69     _barrier_set(BarrierSet::barrier_set()->barrier_set_c2())
  70 {
  71   _exceptions = NULL;
  72   set_map(NULL);
  73   debug_only(_sp = -99);
  74   debug_only(set_bci(-99));
  75 }
  76 
  77 
  78 
  79 //---------------------------clean_stack---------------------------------------
  80 // Clear away rubbish from the stack area of the JVM state.
  81 // This destroys any arguments that may be waiting on the stack.
  82 void GraphKit::clean_stack(int from_sp) {
  83   SafePointNode* map      = this->map();
  84   JVMState*      jvms     = this->jvms();
  85   int            stk_size = jvms->stk_size();
  86   int            stkoff   = jvms->stkoff();
  87   Node*          top      = this->top();
  88   for (int i = from_sp; i < stk_size; i++) {
  89     if (map->in(stkoff + i) != top) {
  90       map->set_req(stkoff + i, top);
  91     }
  92   }
  93 }
  94 
  95 
  96 //--------------------------------sync_jvms-----------------------------------
  97 // Make sure our current jvms agrees with our parse state.
  98 JVMState* GraphKit::sync_jvms() const {
  99   JVMState* jvms = this->jvms();
 100   jvms->set_bci(bci());       // Record the new bci in the JVMState
 101   jvms->set_sp(sp());         // Record the new sp in the JVMState
 102   assert(jvms_in_sync(), "jvms is now in sync");
 103   return jvms;
 104 }
 105 
 106 //--------------------------------sync_jvms_for_reexecute---------------------
 107 // Make sure our current jvms agrees with our parse state.  This version
 108 // uses the reexecute_sp for reexecuting bytecodes.
 109 JVMState* GraphKit::sync_jvms_for_reexecute() {
 110   JVMState* jvms = this->jvms();
 111   jvms->set_bci(bci());          // Record the new bci in the JVMState
 112   jvms->set_sp(reexecute_sp());  // Record the new sp in the JVMState
 113   return jvms;
 114 }
 115 
 116 #ifdef ASSERT
 117 bool GraphKit::jvms_in_sync() const {
 118   Parse* parse = is_Parse();
 119   if (parse == NULL) {
 120     if (bci() !=      jvms()->bci())          return false;
 121     if (sp()  != (int)jvms()->sp())           return false;
 122     return true;
 123   }
 124   if (jvms()->method() != parse->method())    return false;
 125   if (jvms()->bci()    != parse->bci())       return false;
 126   int jvms_sp = jvms()->sp();
 127   if (jvms_sp          != parse->sp())        return false;
 128   int jvms_depth = jvms()->depth();
 129   if (jvms_depth       != parse->depth())     return false;
 130   return true;
 131 }
 132 
 133 // Local helper checks for special internal merge points
 134 // used to accumulate and merge exception states.
 135 // They are marked by the region's in(0) edge being the map itself.
 136 // Such merge points must never "escape" into the parser at large,
 137 // until they have been handed to gvn.transform.
 138 static bool is_hidden_merge(Node* reg) {
 139   if (reg == NULL)  return false;
 140   if (reg->is_Phi()) {
 141     reg = reg->in(0);
 142     if (reg == NULL)  return false;
 143   }
 144   return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root();
 145 }
 146 
 147 void GraphKit::verify_map() const {
 148   if (map() == NULL)  return;  // null map is OK
 149   assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
 150   assert(!map()->has_exceptions(),    "call add_exception_states_from 1st");
 151   assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
 152 }
 153 
 154 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
 155   assert(ex_map->next_exception() == NULL, "not already part of a chain");
 156   assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
 157 }
 158 #endif
 159 
 160 //---------------------------stop_and_kill_map---------------------------------
 161 // Set _map to NULL, signalling a stop to further bytecode execution.
 162 // First smash the current map's control to a constant, to mark it dead.
 163 void GraphKit::stop_and_kill_map() {
 164   SafePointNode* dead_map = stop();
 165   if (dead_map != NULL) {
 166     dead_map->disconnect_inputs(NULL, C); // Mark the map as killed.
 167     assert(dead_map->is_killed(), "must be so marked");
 168   }
 169 }
 170 
 171 
 172 //--------------------------------stopped--------------------------------------
 173 // Tell if _map is NULL, or control is top.
 174 bool GraphKit::stopped() {
 175   if (map() == NULL)           return true;
 176   else if (control() == top()) return true;
 177   else                         return false;
 178 }
 179 
 180 
 181 //-----------------------------has_ex_handler----------------------------------
 182 // Tell if this method or any caller method has exception handlers.
 183 bool GraphKit::has_ex_handler() {
 184   for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) {
 185     if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
 186       return true;
 187     }
 188   }
 189   return false;
 190 }
 191 
 192 //------------------------------save_ex_oop------------------------------------
 193 // Save an exception without blowing stack contents or other JVM state.
 194 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
 195   assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
 196   ex_map->add_req(ex_oop);
 197   debug_only(verify_exception_state(ex_map));
 198 }
 199 
 200 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
 201   assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
 202   Node* ex_oop = ex_map->in(ex_map->req()-1);
 203   if (clear_it)  ex_map->del_req(ex_map->req()-1);
 204   return ex_oop;
 205 }
 206 
 207 //-----------------------------saved_ex_oop------------------------------------
 208 // Recover a saved exception from its map.
 209 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
 210   return common_saved_ex_oop(ex_map, false);
 211 }
 212 
 213 //--------------------------clear_saved_ex_oop---------------------------------
 214 // Erase a previously saved exception from its map.
 215 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
 216   return common_saved_ex_oop(ex_map, true);
 217 }
 218 
 219 #ifdef ASSERT
 220 //---------------------------has_saved_ex_oop----------------------------------
 221 // Erase a previously saved exception from its map.
 222 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
 223   return ex_map->req() == ex_map->jvms()->endoff()+1;
 224 }
 225 #endif
 226 
 227 //-------------------------make_exception_state--------------------------------
 228 // Turn the current JVM state into an exception state, appending the ex_oop.
 229 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
 230   sync_jvms();
 231   SafePointNode* ex_map = stop();  // do not manipulate this map any more
 232   set_saved_ex_oop(ex_map, ex_oop);
 233   return ex_map;
 234 }
 235 
 236 
 237 //--------------------------add_exception_state--------------------------------
 238 // Add an exception to my list of exceptions.
 239 void GraphKit::add_exception_state(SafePointNode* ex_map) {
 240   if (ex_map == NULL || ex_map->control() == top()) {
 241     return;
 242   }
 243 #ifdef ASSERT
 244   verify_exception_state(ex_map);
 245   if (has_exceptions()) {
 246     assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
 247   }
 248 #endif
 249 
 250   // If there is already an exception of exactly this type, merge with it.
 251   // In particular, null-checks and other low-level exceptions common up here.
 252   Node*       ex_oop  = saved_ex_oop(ex_map);
 253   const Type* ex_type = _gvn.type(ex_oop);
 254   if (ex_oop == top()) {
 255     // No action needed.
 256     return;
 257   }
 258   assert(ex_type->isa_instptr(), "exception must be an instance");
 259   for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) {
 260     const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
 261     // We check sp also because call bytecodes can generate exceptions
 262     // both before and after arguments are popped!
 263     if (ex_type2 == ex_type
 264         && e2->_jvms->sp() == ex_map->_jvms->sp()) {
 265       combine_exception_states(ex_map, e2);
 266       return;
 267     }
 268   }
 269 
 270   // No pre-existing exception of the same type.  Chain it on the list.
 271   push_exception_state(ex_map);
 272 }
 273 
 274 //-----------------------add_exception_states_from-----------------------------
 275 void GraphKit::add_exception_states_from(JVMState* jvms) {
 276   SafePointNode* ex_map = jvms->map()->next_exception();
 277   if (ex_map != NULL) {
 278     jvms->map()->set_next_exception(NULL);
 279     for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) {
 280       next_map = ex_map->next_exception();
 281       ex_map->set_next_exception(NULL);
 282       add_exception_state(ex_map);
 283     }
 284   }
 285 }
 286 
 287 //-----------------------transfer_exceptions_into_jvms-------------------------
 288 JVMState* GraphKit::transfer_exceptions_into_jvms() {
 289   if (map() == NULL) {
 290     // We need a JVMS to carry the exceptions, but the map has gone away.
 291     // Create a scratch JVMS, cloned from any of the exception states...
 292     if (has_exceptions()) {
 293       _map = _exceptions;
 294       _map = clone_map();
 295       _map->set_next_exception(NULL);
 296       clear_saved_ex_oop(_map);
 297       debug_only(verify_map());
 298     } else {
 299       // ...or created from scratch
 300       JVMState* jvms = new (C) JVMState(_method, NULL);
 301       jvms->set_bci(_bci);
 302       jvms->set_sp(_sp);
 303       jvms->set_map(new SafePointNode(TypeFunc::Parms, jvms));
 304       set_jvms(jvms);
 305       for (uint i = 0; i < map()->req(); i++)  map()->init_req(i, top());
 306       set_all_memory(top());
 307       while (map()->req() < jvms->endoff())  map()->add_req(top());
 308     }
 309     // (This is a kludge, in case you didn't notice.)
 310     set_control(top());
 311   }
 312   JVMState* jvms = sync_jvms();
 313   assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
 314   jvms->map()->set_next_exception(_exceptions);
 315   _exceptions = NULL;   // done with this set of exceptions
 316   return jvms;
 317 }
 318 
 319 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
 320   assert(is_hidden_merge(dstphi), "must be a special merge node");
 321   assert(is_hidden_merge(srcphi), "must be a special merge node");
 322   uint limit = srcphi->req();
 323   for (uint i = PhiNode::Input; i < limit; i++) {
 324     dstphi->add_req(srcphi->in(i));
 325   }
 326 }
 327 static inline void add_one_req(Node* dstphi, Node* src) {
 328   assert(is_hidden_merge(dstphi), "must be a special merge node");
 329   assert(!is_hidden_merge(src), "must not be a special merge node");
 330   dstphi->add_req(src);
 331 }
 332 
 333 //-----------------------combine_exception_states------------------------------
 334 // This helper function combines exception states by building phis on a
 335 // specially marked state-merging region.  These regions and phis are
 336 // untransformed, and can build up gradually.  The region is marked by
 337 // having a control input of its exception map, rather than NULL.  Such
 338 // regions do not appear except in this function, and in use_exception_state.
 339 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
 340   if (failing())  return;  // dying anyway...
 341   JVMState* ex_jvms = ex_map->_jvms;
 342   assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
 343   assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
 344   assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
 345   assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
 346   assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects");
 347   assert(ex_map->req() == phi_map->req(), "matching maps");
 348   uint tos = ex_jvms->stkoff() + ex_jvms->sp();
 349   Node*         hidden_merge_mark = root();
 350   Node*         region  = phi_map->control();
 351   MergeMemNode* phi_mem = phi_map->merged_memory();
 352   MergeMemNode* ex_mem  = ex_map->merged_memory();
 353   if (region->in(0) != hidden_merge_mark) {
 354     // The control input is not (yet) a specially-marked region in phi_map.
 355     // Make it so, and build some phis.
 356     region = new RegionNode(2);
 357     _gvn.set_type(region, Type::CONTROL);
 358     region->set_req(0, hidden_merge_mark);  // marks an internal ex-state
 359     region->init_req(1, phi_map->control());
 360     phi_map->set_control(region);
 361     Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
 362     record_for_igvn(io_phi);
 363     _gvn.set_type(io_phi, Type::ABIO);
 364     phi_map->set_i_o(io_phi);
 365     for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
 366       Node* m = mms.memory();
 367       Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
 368       record_for_igvn(m_phi);
 369       _gvn.set_type(m_phi, Type::MEMORY);
 370       mms.set_memory(m_phi);
 371     }
 372   }
 373 
 374   // Either or both of phi_map and ex_map might already be converted into phis.
 375   Node* ex_control = ex_map->control();
 376   // if there is special marking on ex_map also, we add multiple edges from src
 377   bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
 378   // how wide was the destination phi_map, originally?
 379   uint orig_width = region->req();
 380 
 381   if (add_multiple) {
 382     add_n_reqs(region, ex_control);
 383     add_n_reqs(phi_map->i_o(), ex_map->i_o());
 384   } else {
 385     // ex_map has no merges, so we just add single edges everywhere
 386     add_one_req(region, ex_control);
 387     add_one_req(phi_map->i_o(), ex_map->i_o());
 388   }
 389   for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
 390     if (mms.is_empty()) {
 391       // get a copy of the base memory, and patch some inputs into it
 392       const TypePtr* adr_type = mms.adr_type(C);
 393       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
 394       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
 395       mms.set_memory(phi);
 396       // Prepare to append interesting stuff onto the newly sliced phi:
 397       while (phi->req() > orig_width)  phi->del_req(phi->req()-1);
 398     }
 399     // Append stuff from ex_map:
 400     if (add_multiple) {
 401       add_n_reqs(mms.memory(), mms.memory2());
 402     } else {
 403       add_one_req(mms.memory(), mms.memory2());
 404     }
 405   }
 406   uint limit = ex_map->req();
 407   for (uint i = TypeFunc::Parms; i < limit; i++) {
 408     // Skip everything in the JVMS after tos.  (The ex_oop follows.)
 409     if (i == tos)  i = ex_jvms->monoff();
 410     Node* src = ex_map->in(i);
 411     Node* dst = phi_map->in(i);
 412     if (src != dst) {
 413       PhiNode* phi;
 414       if (dst->in(0) != region) {
 415         dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
 416         record_for_igvn(phi);
 417         _gvn.set_type(phi, phi->type());
 418         phi_map->set_req(i, dst);
 419         // Prepare to append interesting stuff onto the new phi:
 420         while (dst->req() > orig_width)  dst->del_req(dst->req()-1);
 421       } else {
 422         assert(dst->is_Phi(), "nobody else uses a hidden region");
 423         phi = dst->as_Phi();
 424       }
 425       if (add_multiple && src->in(0) == ex_control) {
 426         // Both are phis.
 427         add_n_reqs(dst, src);
 428       } else {
 429         while (dst->req() < region->req())  add_one_req(dst, src);
 430       }
 431       const Type* srctype = _gvn.type(src);
 432       if (phi->type() != srctype) {
 433         const Type* dsttype = phi->type()->meet_speculative(srctype);
 434         if (phi->type() != dsttype) {
 435           phi->set_type(dsttype);
 436           _gvn.set_type(phi, dsttype);
 437         }
 438       }
 439     }
 440   }
 441   phi_map->merge_replaced_nodes_with(ex_map);
 442 }
 443 
 444 //--------------------------use_exception_state--------------------------------
 445 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
 446   if (failing()) { stop(); return top(); }
 447   Node* region = phi_map->control();
 448   Node* hidden_merge_mark = root();
 449   assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
 450   Node* ex_oop = clear_saved_ex_oop(phi_map);
 451   if (region->in(0) == hidden_merge_mark) {
 452     // Special marking for internal ex-states.  Process the phis now.
 453     region->set_req(0, region);  // now it's an ordinary region
 454     set_jvms(phi_map->jvms());   // ...so now we can use it as a map
 455     // Note: Setting the jvms also sets the bci and sp.
 456     set_control(_gvn.transform(region));
 457     uint tos = jvms()->stkoff() + sp();
 458     for (uint i = 1; i < tos; i++) {
 459       Node* x = phi_map->in(i);
 460       if (x->in(0) == region) {
 461         assert(x->is_Phi(), "expected a special phi");
 462         phi_map->set_req(i, _gvn.transform(x));
 463       }
 464     }
 465     for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
 466       Node* x = mms.memory();
 467       if (x->in(0) == region) {
 468         assert(x->is_Phi(), "nobody else uses a hidden region");
 469         mms.set_memory(_gvn.transform(x));
 470       }
 471     }
 472     if (ex_oop->in(0) == region) {
 473       assert(ex_oop->is_Phi(), "expected a special phi");
 474       ex_oop = _gvn.transform(ex_oop);
 475     }
 476   } else {
 477     set_jvms(phi_map->jvms());
 478   }
 479 
 480   assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
 481   assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
 482   return ex_oop;
 483 }
 484 
 485 //---------------------------------java_bc-------------------------------------
 486 Bytecodes::Code GraphKit::java_bc() const {
 487   ciMethod* method = this->method();
 488   int       bci    = this->bci();
 489   if (method != NULL && bci != InvocationEntryBci)
 490     return method->java_code_at_bci(bci);
 491   else
 492     return Bytecodes::_illegal;
 493 }
 494 
 495 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
 496                                                           bool must_throw) {
 497     // if the exception capability is set, then we will generate code
 498     // to check the JavaThread.should_post_on_exceptions flag to see
 499     // if we actually need to report exception events (for this
 500     // thread).  If we don't need to report exception events, we will
 501     // take the normal fast path provided by add_exception_events.  If
 502     // exception event reporting is enabled for this thread, we will
 503     // take the uncommon_trap in the BuildCutout below.
 504 
 505     // first must access the should_post_on_exceptions_flag in this thread's JavaThread
 506     Node* jthread = _gvn.transform(new ThreadLocalNode());
 507     Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
 508     Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw, MemNode::unordered);
 509 
 510     // Test the should_post_on_exceptions_flag vs. 0
 511     Node* chk = _gvn.transform( new CmpINode(should_post_flag, intcon(0)) );
 512     Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
 513 
 514     // Branch to slow_path if should_post_on_exceptions_flag was true
 515     { BuildCutout unless(this, tst, PROB_MAX);
 516       // Do not try anything fancy if we're notifying the VM on every throw.
 517       // Cf. case Bytecodes::_athrow in parse2.cpp.
 518       uncommon_trap(reason, Deoptimization::Action_none,
 519                     (ciKlass*)NULL, (char*)NULL, must_throw);
 520     }
 521 
 522 }
 523 
 524 //------------------------------builtin_throw----------------------------------
 525 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) {
 526   bool must_throw = true;
 527 
 528   if (env()->jvmti_can_post_on_exceptions()) {
 529     // check if we must post exception events, take uncommon trap if so
 530     uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
 531     // here if should_post_on_exceptions is false
 532     // continue on with the normal codegen
 533   }
 534 
 535   // If this particular condition has not yet happened at this
 536   // bytecode, then use the uncommon trap mechanism, and allow for
 537   // a future recompilation if several traps occur here.
 538   // If the throw is hot, try to use a more complicated inline mechanism
 539   // which keeps execution inside the compiled code.
 540   bool treat_throw_as_hot = false;
 541   ciMethodData* md = method()->method_data();
 542 
 543   if (ProfileTraps) {
 544     if (too_many_traps(reason)) {
 545       treat_throw_as_hot = true;
 546     }
 547     // (If there is no MDO at all, assume it is early in
 548     // execution, and that any deopts are part of the
 549     // startup transient, and don't need to be remembered.)
 550 
 551     // Also, if there is a local exception handler, treat all throws
 552     // as hot if there has been at least one in this method.
 553     if (C->trap_count(reason) != 0
 554         && method()->method_data()->trap_count(reason) != 0
 555         && has_ex_handler()) {
 556         treat_throw_as_hot = true;
 557     }
 558   }
 559 
 560   // If this throw happens frequently, an uncommon trap might cause
 561   // a performance pothole.  If there is a local exception handler,
 562   // and if this particular bytecode appears to be deoptimizing often,
 563   // let us handle the throw inline, with a preconstructed instance.
 564   // Note:   If the deopt count has blown up, the uncommon trap
 565   // runtime is going to flush this nmethod, not matter what.
 566   if (treat_throw_as_hot
 567       && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) {
 568     // If the throw is local, we use a pre-existing instance and
 569     // punt on the backtrace.  This would lead to a missing backtrace
 570     // (a repeat of 4292742) if the backtrace object is ever asked
 571     // for its backtrace.
 572     // Fixing this remaining case of 4292742 requires some flavor of
 573     // escape analysis.  Leave that for the future.
 574     ciInstance* ex_obj = NULL;
 575     switch (reason) {
 576     case Deoptimization::Reason_null_check:
 577       ex_obj = env()->NullPointerException_instance();
 578       break;
 579     case Deoptimization::Reason_div0_check:
 580       ex_obj = env()->ArithmeticException_instance();
 581       break;
 582     case Deoptimization::Reason_range_check:
 583       ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
 584       break;
 585     case Deoptimization::Reason_class_check:
 586       if (java_bc() == Bytecodes::_aastore) {
 587         ex_obj = env()->ArrayStoreException_instance();
 588       } else {
 589         ex_obj = env()->ClassCastException_instance();
 590       }
 591       break;
 592     default:
 593       break;
 594     }
 595     if (failing()) { stop(); return; }  // exception allocation might fail
 596     if (ex_obj != NULL) {
 597       // Cheat with a preallocated exception object.
 598       if (C->log() != NULL)
 599         C->log()->elem("hot_throw preallocated='1' reason='%s'",
 600                        Deoptimization::trap_reason_name(reason));
 601       const TypeInstPtr* ex_con  = TypeInstPtr::make(ex_obj);
 602       Node*              ex_node = _gvn.transform(ConNode::make(ex_con));
 603 
 604       // Clear the detail message of the preallocated exception object.
 605       // Weblogic sometimes mutates the detail message of exceptions
 606       // using reflection.
 607       int offset = java_lang_Throwable::get_detailMessage_offset();
 608       const TypePtr* adr_typ = ex_con->add_offset(offset);
 609 
 610       Node *adr = basic_plus_adr(ex_node, ex_node, offset);
 611       const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
 612       Node *store = access_store_at(control(), ex_node, adr, adr_typ, null(), val_type, T_OBJECT, IN_HEAP);
 613 
 614       add_exception_state(make_exception_state(ex_node));
 615       return;
 616     }
 617   }
 618 
 619   // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
 620   // It won't be much cheaper than bailing to the interp., since we'll
 621   // have to pass up all the debug-info, and the runtime will have to
 622   // create the stack trace.
 623 
 624   // Usual case:  Bail to interpreter.
 625   // Reserve the right to recompile if we haven't seen anything yet.
 626 
 627   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? C->method() : NULL;
 628   Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
 629   if (treat_throw_as_hot
 630       && (method()->method_data()->trap_recompiled_at(bci(), m)
 631           || C->too_many_traps(reason))) {
 632     // We cannot afford to take more traps here.  Suffer in the interpreter.
 633     if (C->log() != NULL)
 634       C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
 635                      Deoptimization::trap_reason_name(reason),
 636                      C->trap_count(reason));
 637     action = Deoptimization::Action_none;
 638   }
 639 
 640   // "must_throw" prunes the JVM state to include only the stack, if there
 641   // are no local exception handlers.  This should cut down on register
 642   // allocation time and code size, by drastically reducing the number
 643   // of in-edges on the call to the uncommon trap.
 644 
 645   uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw);
 646 }
 647 
 648 
 649 //----------------------------PreserveJVMState---------------------------------
 650 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
 651   debug_only(kit->verify_map());
 652   _kit    = kit;
 653   _map    = kit->map();   // preserve the map
 654   _sp     = kit->sp();
 655   kit->set_map(clone_map ? kit->clone_map() : NULL);
 656 #ifdef ASSERT
 657   _bci    = kit->bci();
 658   Parse* parser = kit->is_Parse();
 659   int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
 660   _block  = block;
 661 #endif
 662 }
 663 PreserveJVMState::~PreserveJVMState() {
 664   GraphKit* kit = _kit;
 665 #ifdef ASSERT
 666   assert(kit->bci() == _bci, "bci must not shift");
 667   Parse* parser = kit->is_Parse();
 668   int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
 669   assert(block == _block,    "block must not shift");
 670 #endif
 671   kit->set_map(_map);
 672   kit->set_sp(_sp);
 673 }
 674 
 675 
 676 //-----------------------------BuildCutout-------------------------------------
 677 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
 678   : PreserveJVMState(kit)
 679 {
 680   assert(p->is_Con() || p->is_Bool(), "test must be a bool");
 681   SafePointNode* outer_map = _map;   // preserved map is caller's
 682   SafePointNode* inner_map = kit->map();
 683   IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
 684   outer_map->set_control(kit->gvn().transform( new IfTrueNode(iff) ));
 685   inner_map->set_control(kit->gvn().transform( new IfFalseNode(iff) ));
 686 }
 687 BuildCutout::~BuildCutout() {
 688   GraphKit* kit = _kit;
 689   assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
 690 }
 691 
 692 //---------------------------PreserveReexecuteState----------------------------
 693 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
 694   assert(!kit->stopped(), "must call stopped() before");
 695   _kit    =    kit;
 696   _sp     =    kit->sp();
 697   _reexecute = kit->jvms()->_reexecute;
 698 }
 699 PreserveReexecuteState::~PreserveReexecuteState() {
 700   if (_kit->stopped()) return;
 701   _kit->jvms()->_reexecute = _reexecute;
 702   _kit->set_sp(_sp);
 703 }
 704 
 705 //------------------------------clone_map--------------------------------------
 706 // Implementation of PreserveJVMState
 707 //
 708 // Only clone_map(...) here. If this function is only used in the
 709 // PreserveJVMState class we may want to get rid of this extra
 710 // function eventually and do it all there.
 711 
 712 SafePointNode* GraphKit::clone_map() {
 713   if (map() == NULL)  return NULL;
 714 
 715   // Clone the memory edge first
 716   Node* mem = MergeMemNode::make(map()->memory());
 717   gvn().set_type_bottom(mem);
 718 
 719   SafePointNode *clonemap = (SafePointNode*)map()->clone();
 720   JVMState* jvms = this->jvms();
 721   JVMState* clonejvms = jvms->clone_shallow(C);
 722   clonemap->set_memory(mem);
 723   clonemap->set_jvms(clonejvms);
 724   clonejvms->set_map(clonemap);
 725   record_for_igvn(clonemap);
 726   gvn().set_type_bottom(clonemap);
 727   return clonemap;
 728 }
 729 
 730 
 731 //-----------------------------set_map_clone-----------------------------------
 732 void GraphKit::set_map_clone(SafePointNode* m) {
 733   _map = m;
 734   _map = clone_map();
 735   _map->set_next_exception(NULL);
 736   debug_only(verify_map());
 737 }
 738 
 739 
 740 //----------------------------kill_dead_locals---------------------------------
 741 // Detect any locals which are known to be dead, and force them to top.
 742 void GraphKit::kill_dead_locals() {
 743   // Consult the liveness information for the locals.  If any
 744   // of them are unused, then they can be replaced by top().  This
 745   // should help register allocation time and cut down on the size
 746   // of the deoptimization information.
 747 
 748   // This call is made from many of the bytecode handling
 749   // subroutines called from the Big Switch in do_one_bytecode.
 750   // Every bytecode which might include a slow path is responsible
 751   // for killing its dead locals.  The more consistent we
 752   // are about killing deads, the fewer useless phis will be
 753   // constructed for them at various merge points.
 754 
 755   // bci can be -1 (InvocationEntryBci).  We return the entry
 756   // liveness for the method.
 757 
 758   if (method() == NULL || method()->code_size() == 0) {
 759     // We are building a graph for a call to a native method.
 760     // All locals are live.
 761     return;
 762   }
 763 
 764   ResourceMark rm;
 765 
 766   // Consult the liveness information for the locals.  If any
 767   // of them are unused, then they can be replaced by top().  This
 768   // should help register allocation time and cut down on the size
 769   // of the deoptimization information.
 770   MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
 771 
 772   int len = (int)live_locals.size();
 773   assert(len <= jvms()->loc_size(), "too many live locals");
 774   for (int local = 0; local < len; local++) {
 775     if (!live_locals.at(local)) {
 776       set_local(local, top());
 777     }
 778   }
 779 }
 780 
 781 #ifdef ASSERT
 782 //-------------------------dead_locals_are_killed------------------------------
 783 // Return true if all dead locals are set to top in the map.
 784 // Used to assert "clean" debug info at various points.
 785 bool GraphKit::dead_locals_are_killed() {
 786   if (method() == NULL || method()->code_size() == 0) {
 787     // No locals need to be dead, so all is as it should be.
 788     return true;
 789   }
 790 
 791   // Make sure somebody called kill_dead_locals upstream.
 792   ResourceMark rm;
 793   for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
 794     if (jvms->loc_size() == 0)  continue;  // no locals to consult
 795     SafePointNode* map = jvms->map();
 796     ciMethod* method = jvms->method();
 797     int       bci    = jvms->bci();
 798     if (jvms == this->jvms()) {
 799       bci = this->bci();  // it might not yet be synched
 800     }
 801     MethodLivenessResult live_locals = method->liveness_at_bci(bci);
 802     int len = (int)live_locals.size();
 803     if (!live_locals.is_valid() || len == 0)
 804       // This method is trivial, or is poisoned by a breakpoint.
 805       return true;
 806     assert(len == jvms->loc_size(), "live map consistent with locals map");
 807     for (int local = 0; local < len; local++) {
 808       if (!live_locals.at(local) && map->local(jvms, local) != top()) {
 809         if (PrintMiscellaneous && (Verbose || WizardMode)) {
 810           tty->print_cr("Zombie local %d: ", local);
 811           jvms->dump();
 812         }
 813         return false;
 814       }
 815     }
 816   }
 817   return true;
 818 }
 819 
 820 #endif //ASSERT
 821 
 822 // Helper function for enforcing certain bytecodes to reexecute if
 823 // deoptimization happens
 824 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
 825   ciMethod* cur_method = jvms->method();
 826   int       cur_bci   = jvms->bci();
 827   if (cur_method != NULL && cur_bci != InvocationEntryBci) {
 828     Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
 829     return Interpreter::bytecode_should_reexecute(code) ||
 830            (is_anewarray && code == Bytecodes::_multianewarray);
 831     // Reexecute _multianewarray bytecode which was replaced with
 832     // sequence of [a]newarray. See Parse::do_multianewarray().
 833     //
 834     // Note: interpreter should not have it set since this optimization
 835     // is limited by dimensions and guarded by flag so in some cases
 836     // multianewarray() runtime calls will be generated and
 837     // the bytecode should not be reexecutes (stack will not be reset).
 838   } else
 839     return false;
 840 }
 841 
 842 // Helper function for adding JVMState and debug information to node
 843 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
 844   // Add the safepoint edges to the call (or other safepoint).
 845 
 846   // Make sure dead locals are set to top.  This
 847   // should help register allocation time and cut down on the size
 848   // of the deoptimization information.
 849   assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
 850 
 851   // Walk the inline list to fill in the correct set of JVMState's
 852   // Also fill in the associated edges for each JVMState.
 853 
 854   // If the bytecode needs to be reexecuted we need to put
 855   // the arguments back on the stack.
 856   const bool should_reexecute = jvms()->should_reexecute();
 857   JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
 858 
 859   // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
 860   // undefined if the bci is different.  This is normal for Parse but it
 861   // should not happen for LibraryCallKit because only one bci is processed.
 862   assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
 863          "in LibraryCallKit the reexecute bit should not change");
 864 
 865   // If we are guaranteed to throw, we can prune everything but the
 866   // input to the current bytecode.
 867   bool can_prune_locals = false;
 868   uint stack_slots_not_pruned = 0;
 869   int inputs = 0, depth = 0;
 870   if (must_throw) {
 871     assert(method() == youngest_jvms->method(), "sanity");
 872     if (compute_stack_effects(inputs, depth)) {
 873       can_prune_locals = true;
 874       stack_slots_not_pruned = inputs;
 875     }
 876   }
 877 
 878   if (env()->should_retain_local_variables()) {
 879     // At any safepoint, this method can get breakpointed, which would
 880     // then require an immediate deoptimization.
 881     can_prune_locals = false;  // do not prune locals
 882     stack_slots_not_pruned = 0;
 883   }
 884 
 885   // do not scribble on the input jvms
 886   JVMState* out_jvms = youngest_jvms->clone_deep(C);
 887   call->set_jvms(out_jvms); // Start jvms list for call node
 888 
 889   // For a known set of bytecodes, the interpreter should reexecute them if
 890   // deoptimization happens. We set the reexecute state for them here
 891   if (out_jvms->is_reexecute_undefined() && //don't change if already specified
 892       should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
 893     out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
 894   }
 895 
 896   // Presize the call:
 897   DEBUG_ONLY(uint non_debug_edges = call->req());
 898   call->add_req_batch(top(), youngest_jvms->debug_depth());
 899   assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
 900 
 901   // Set up edges so that the call looks like this:
 902   //  Call [state:] ctl io mem fptr retadr
 903   //       [parms:] parm0 ... parmN
 904   //       [root:]  loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 905   //    [...mid:]   loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
 906   //       [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 907   // Note that caller debug info precedes callee debug info.
 908 
 909   // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
 910   uint debug_ptr = call->req();
 911 
 912   // Loop over the map input edges associated with jvms, add them
 913   // to the call node, & reset all offsets to match call node array.
 914   for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) {
 915     uint debug_end   = debug_ptr;
 916     uint debug_start = debug_ptr - in_jvms->debug_size();
 917     debug_ptr = debug_start;  // back up the ptr
 918 
 919     uint p = debug_start;  // walks forward in [debug_start, debug_end)
 920     uint j, k, l;
 921     SafePointNode* in_map = in_jvms->map();
 922     out_jvms->set_map(call);
 923 
 924     if (can_prune_locals) {
 925       assert(in_jvms->method() == out_jvms->method(), "sanity");
 926       // If the current throw can reach an exception handler in this JVMS,
 927       // then we must keep everything live that can reach that handler.
 928       // As a quick and dirty approximation, we look for any handlers at all.
 929       if (in_jvms->method()->has_exception_handlers()) {
 930         can_prune_locals = false;
 931       }
 932     }
 933 
 934     // Add the Locals
 935     k = in_jvms->locoff();
 936     l = in_jvms->loc_size();
 937     out_jvms->set_locoff(p);
 938     if (!can_prune_locals) {
 939       for (j = 0; j < l; j++)
 940         call->set_req(p++, in_map->in(k+j));
 941     } else {
 942       p += l;  // already set to top above by add_req_batch
 943     }
 944 
 945     // Add the Expression Stack
 946     k = in_jvms->stkoff();
 947     l = in_jvms->sp();
 948     out_jvms->set_stkoff(p);
 949     if (!can_prune_locals) {
 950       for (j = 0; j < l; j++)
 951         call->set_req(p++, in_map->in(k+j));
 952     } else if (can_prune_locals && stack_slots_not_pruned != 0) {
 953       // Divide stack into {S0,...,S1}, where S0 is set to top.
 954       uint s1 = stack_slots_not_pruned;
 955       stack_slots_not_pruned = 0;  // for next iteration
 956       if (s1 > l)  s1 = l;
 957       uint s0 = l - s1;
 958       p += s0;  // skip the tops preinstalled by add_req_batch
 959       for (j = s0; j < l; j++)
 960         call->set_req(p++, in_map->in(k+j));
 961     } else {
 962       p += l;  // already set to top above by add_req_batch
 963     }
 964 
 965     // Add the Monitors
 966     k = in_jvms->monoff();
 967     l = in_jvms->mon_size();
 968     out_jvms->set_monoff(p);
 969     for (j = 0; j < l; j++)
 970       call->set_req(p++, in_map->in(k+j));
 971 
 972     // Copy any scalar object fields.
 973     k = in_jvms->scloff();
 974     l = in_jvms->scl_size();
 975     out_jvms->set_scloff(p);
 976     for (j = 0; j < l; j++)
 977       call->set_req(p++, in_map->in(k+j));
 978 
 979     // Finish the new jvms.
 980     out_jvms->set_endoff(p);
 981 
 982     assert(out_jvms->endoff()     == debug_end,             "fill ptr must match");
 983     assert(out_jvms->depth()      == in_jvms->depth(),      "depth must match");
 984     assert(out_jvms->loc_size()   == in_jvms->loc_size(),   "size must match");
 985     assert(out_jvms->mon_size()   == in_jvms->mon_size(),   "size must match");
 986     assert(out_jvms->scl_size()   == in_jvms->scl_size(),   "size must match");
 987     assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
 988 
 989     // Update the two tail pointers in parallel.
 990     out_jvms = out_jvms->caller();
 991     in_jvms  = in_jvms->caller();
 992   }
 993 
 994   assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
 995 
 996   // Test the correctness of JVMState::debug_xxx accessors:
 997   assert(call->jvms()->debug_start() == non_debug_edges, "");
 998   assert(call->jvms()->debug_end()   == call->req(), "");
 999   assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
1000 }
1001 
1002 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
1003   Bytecodes::Code code = java_bc();
1004   if (code == Bytecodes::_wide) {
1005     code = method()->java_code_at_bci(bci() + 1);
1006   }
1007 
1008   BasicType rtype = T_ILLEGAL;
1009   int       rsize = 0;
1010 
1011   if (code != Bytecodes::_illegal) {
1012     depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1013     rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1014     if (rtype < T_CONFLICT)
1015       rsize = type2size[rtype];
1016   }
1017 
1018   switch (code) {
1019   case Bytecodes::_illegal:
1020     return false;
1021 
1022   case Bytecodes::_ldc:
1023   case Bytecodes::_ldc_w:
1024   case Bytecodes::_ldc2_w:
1025     inputs = 0;
1026     break;
1027 
1028   case Bytecodes::_dup:         inputs = 1;  break;
1029   case Bytecodes::_dup_x1:      inputs = 2;  break;
1030   case Bytecodes::_dup_x2:      inputs = 3;  break;
1031   case Bytecodes::_dup2:        inputs = 2;  break;
1032   case Bytecodes::_dup2_x1:     inputs = 3;  break;
1033   case Bytecodes::_dup2_x2:     inputs = 4;  break;
1034   case Bytecodes::_swap:        inputs = 2;  break;
1035   case Bytecodes::_arraylength: inputs = 1;  break;
1036 
1037   case Bytecodes::_getstatic:
1038   case Bytecodes::_putstatic:
1039   case Bytecodes::_getfield:
1040   case Bytecodes::_putfield:
1041     {
1042       bool ignored_will_link;
1043       ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1044       int      size  = field->type()->size();
1045       bool is_get = (depth >= 0), is_static = (depth & 1);
1046       inputs = (is_static ? 0 : 1);
1047       if (is_get) {
1048         depth = size - inputs;
1049       } else {
1050         inputs += size;        // putxxx pops the value from the stack
1051         depth = - inputs;
1052       }
1053     }
1054     break;
1055 
1056   case Bytecodes::_invokevirtual:
1057   case Bytecodes::_invokespecial:
1058   case Bytecodes::_invokestatic:
1059   case Bytecodes::_invokedynamic:
1060   case Bytecodes::_invokeinterface:
1061     {
1062       bool ignored_will_link;
1063       ciSignature* declared_signature = NULL;
1064       ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1065       assert(declared_signature != NULL, "cannot be null");
1066       inputs   = declared_signature->arg_size_for_bc(code);
1067       int size = declared_signature->return_type()->size();
1068       depth = size - inputs;
1069     }
1070     break;
1071 
1072   case Bytecodes::_multianewarray:
1073     {
1074       ciBytecodeStream iter(method());
1075       iter.reset_to_bci(bci());
1076       iter.next();
1077       inputs = iter.get_dimensions();
1078       assert(rsize == 1, "");
1079       depth = rsize - inputs;
1080     }
1081     break;
1082 
1083   case Bytecodes::_ireturn:
1084   case Bytecodes::_lreturn:
1085   case Bytecodes::_freturn:
1086   case Bytecodes::_dreturn:
1087   case Bytecodes::_areturn:
1088     assert(rsize == -depth, "");
1089     inputs = rsize;
1090     break;
1091 
1092   case Bytecodes::_jsr:
1093   case Bytecodes::_jsr_w:
1094     inputs = 0;
1095     depth  = 1;                  // S.B. depth=1, not zero
1096     break;
1097 
1098   default:
1099     // bytecode produces a typed result
1100     inputs = rsize - depth;
1101     assert(inputs >= 0, "");
1102     break;
1103   }
1104 
1105 #ifdef ASSERT
1106   // spot check
1107   int outputs = depth + inputs;
1108   assert(outputs >= 0, "sanity");
1109   switch (code) {
1110   case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1111   case Bytecodes::_athrow:    assert(inputs == 1 && outputs == 0, ""); break;
1112   case Bytecodes::_aload_0:   assert(inputs == 0 && outputs == 1, ""); break;
1113   case Bytecodes::_return:    assert(inputs == 0 && outputs == 0, ""); break;
1114   case Bytecodes::_drem:      assert(inputs == 4 && outputs == 2, ""); break;
1115   default:                    break;
1116   }
1117 #endif //ASSERT
1118 
1119   return true;
1120 }
1121 
1122 
1123 
1124 //------------------------------basic_plus_adr---------------------------------
1125 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1126   // short-circuit a common case
1127   if (offset == intcon(0))  return ptr;
1128   return _gvn.transform( new AddPNode(base, ptr, offset) );
1129 }
1130 
1131 Node* GraphKit::ConvI2L(Node* offset) {
1132   // short-circuit a common case
1133   jint offset_con = find_int_con(offset, Type::OffsetBot);
1134   if (offset_con != Type::OffsetBot) {
1135     return longcon((jlong) offset_con);
1136   }
1137   return _gvn.transform( new ConvI2LNode(offset));
1138 }
1139 
1140 Node* GraphKit::ConvI2UL(Node* offset) {
1141   juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1142   if (offset_con != (juint) Type::OffsetBot) {
1143     return longcon((julong) offset_con);
1144   }
1145   Node* conv = _gvn.transform( new ConvI2LNode(offset));
1146   Node* mask = _gvn.transform(ConLNode::make((julong) max_juint));
1147   return _gvn.transform( new AndLNode(conv, mask) );
1148 }
1149 
1150 Node* GraphKit::ConvL2I(Node* offset) {
1151   // short-circuit a common case
1152   jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1153   if (offset_con != (jlong)Type::OffsetBot) {
1154     return intcon((int) offset_con);
1155   }
1156   return _gvn.transform( new ConvL2INode(offset));
1157 }
1158 
1159 //-------------------------load_object_klass-----------------------------------
1160 Node* GraphKit::load_object_klass(Node* obj) {
1161   // Special-case a fresh allocation to avoid building nodes:
1162   Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1163   if (akls != NULL)  return akls;
1164   Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1165   return _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), k_adr, TypeInstPtr::KLASS));
1166 }
1167 
1168 //-------------------------load_array_length-----------------------------------
1169 Node* GraphKit::load_array_length(Node* array) {
1170   // Special-case a fresh allocation to avoid building nodes:
1171   AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn);
1172   Node *alen;
1173   if (alloc == NULL) {
1174     Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1175     alen = _gvn.transform( new LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1176   } else {
1177     alen = alloc->Ideal_length();
1178     Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn);
1179     if (ccast != alen) {
1180       alen = _gvn.transform(ccast);
1181     }
1182   }
1183   return alen;
1184 }
1185 
1186 //------------------------------do_null_check----------------------------------
1187 // Helper function to do a NULL pointer check.  Returned value is
1188 // the incoming address with NULL casted away.  You are allowed to use the
1189 // not-null value only if you are control dependent on the test.
1190 #ifndef PRODUCT
1191 extern int explicit_null_checks_inserted,
1192            explicit_null_checks_elided;
1193 #endif
1194 Node* GraphKit::null_check_common(Node* value, BasicType type,
1195                                   // optional arguments for variations:
1196                                   bool assert_null,
1197                                   Node* *null_control,
1198                                   bool speculative) {
1199   assert(!assert_null || null_control == NULL, "not both at once");
1200   if (stopped())  return top();
1201   NOT_PRODUCT(explicit_null_checks_inserted++);
1202 
1203   // Construct NULL check
1204   Node *chk = NULL;
1205   switch(type) {
1206     case T_LONG   : chk = new CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1207     case T_INT    : chk = new CmpINode(value, _gvn.intcon(0)); break;
1208     case T_ARRAY  : // fall through
1209       type = T_OBJECT;  // simplify further tests
1210     case T_OBJECT : {
1211       const Type *t = _gvn.type( value );
1212 
1213       const TypeOopPtr* tp = t->isa_oopptr();
1214       if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded()
1215           // Only for do_null_check, not any of its siblings:
1216           && !assert_null && null_control == NULL) {
1217         // Usually, any field access or invocation on an unloaded oop type
1218         // will simply fail to link, since the statically linked class is
1219         // likely also to be unloaded.  However, in -Xcomp mode, sometimes
1220         // the static class is loaded but the sharper oop type is not.
1221         // Rather than checking for this obscure case in lots of places,
1222         // we simply observe that a null check on an unloaded class
1223         // will always be followed by a nonsense operation, so we
1224         // can just issue the uncommon trap here.
1225         // Our access to the unloaded class will only be correct
1226         // after it has been loaded and initialized, which requires
1227         // a trip through the interpreter.
1228 #ifndef PRODUCT
1229         if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); }
1230 #endif
1231         uncommon_trap(Deoptimization::Reason_unloaded,
1232                       Deoptimization::Action_reinterpret,
1233                       tp->klass(), "!loaded");
1234         return top();
1235       }
1236 
1237       if (assert_null) {
1238         // See if the type is contained in NULL_PTR.
1239         // If so, then the value is already null.
1240         if (t->higher_equal(TypePtr::NULL_PTR)) {
1241           NOT_PRODUCT(explicit_null_checks_elided++);
1242           return value;           // Elided null assert quickly!
1243         }
1244       } else {
1245         // See if mixing in the NULL pointer changes type.
1246         // If so, then the NULL pointer was not allowed in the original
1247         // type.  In other words, "value" was not-null.
1248         if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1249           // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1250           NOT_PRODUCT(explicit_null_checks_elided++);
1251           return value;           // Elided null check quickly!
1252         }
1253       }
1254       chk = new CmpPNode( value, null() );
1255       break;
1256     }
1257 
1258     default:
1259       fatal("unexpected type: %s", type2name(type));
1260   }
1261   assert(chk != NULL, "sanity check");
1262   chk = _gvn.transform(chk);
1263 
1264   BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1265   BoolNode *btst = new BoolNode( chk, btest);
1266   Node   *tst = _gvn.transform( btst );
1267 
1268   //-----------
1269   // if peephole optimizations occurred, a prior test existed.
1270   // If a prior test existed, maybe it dominates as we can avoid this test.
1271   if (tst != btst && type == T_OBJECT) {
1272     // At this point we want to scan up the CFG to see if we can
1273     // find an identical test (and so avoid this test altogether).
1274     Node *cfg = control();
1275     int depth = 0;
1276     while( depth < 16 ) {       // Limit search depth for speed
1277       if( cfg->Opcode() == Op_IfTrue &&
1278           cfg->in(0)->in(1) == tst ) {
1279         // Found prior test.  Use "cast_not_null" to construct an identical
1280         // CastPP (and hence hash to) as already exists for the prior test.
1281         // Return that casted value.
1282         if (assert_null) {
1283           replace_in_map(value, null());
1284           return null();  // do not issue the redundant test
1285         }
1286         Node *oldcontrol = control();
1287         set_control(cfg);
1288         Node *res = cast_not_null(value);
1289         set_control(oldcontrol);
1290         NOT_PRODUCT(explicit_null_checks_elided++);
1291         return res;
1292       }
1293       cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1294       if (cfg == NULL)  break;  // Quit at region nodes
1295       depth++;
1296     }
1297   }
1298 
1299   //-----------
1300   // Branch to failure if null
1301   float ok_prob = PROB_MAX;  // a priori estimate:  nulls never happen
1302   Deoptimization::DeoptReason reason;
1303   if (assert_null) {
1304     reason = Deoptimization::reason_null_assert(speculative);
1305   } else if (type == T_OBJECT) {
1306     reason = Deoptimization::reason_null_check(speculative);
1307   } else {
1308     reason = Deoptimization::Reason_div0_check;
1309   }
1310   // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1311   // ciMethodData::has_trap_at will return a conservative -1 if any
1312   // must-be-null assertion has failed.  This could cause performance
1313   // problems for a method after its first do_null_assert failure.
1314   // Consider using 'Reason_class_check' instead?
1315 
1316   // To cause an implicit null check, we set the not-null probability
1317   // to the maximum (PROB_MAX).  For an explicit check the probability
1318   // is set to a smaller value.
1319   if (null_control != NULL || too_many_traps(reason)) {
1320     // probability is less likely
1321     ok_prob =  PROB_LIKELY_MAG(3);
1322   } else if (!assert_null &&
1323              (ImplicitNullCheckThreshold > 0) &&
1324              method() != NULL &&
1325              (method()->method_data()->trap_count(reason)
1326               >= (uint)ImplicitNullCheckThreshold)) {
1327     ok_prob =  PROB_LIKELY_MAG(3);
1328   }
1329 
1330   if (null_control != NULL) {
1331     IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1332     Node* null_true = _gvn.transform( new IfFalseNode(iff));
1333     set_control(      _gvn.transform( new IfTrueNode(iff)));
1334 #ifndef PRODUCT
1335     if (null_true == top()) {
1336       explicit_null_checks_elided++;
1337     }
1338 #endif
1339     (*null_control) = null_true;
1340   } else {
1341     BuildCutout unless(this, tst, ok_prob);
1342     // Check for optimizer eliding test at parse time
1343     if (stopped()) {
1344       // Failure not possible; do not bother making uncommon trap.
1345       NOT_PRODUCT(explicit_null_checks_elided++);
1346     } else if (assert_null) {
1347       uncommon_trap(reason,
1348                     Deoptimization::Action_make_not_entrant,
1349                     NULL, "assert_null");
1350     } else {
1351       replace_in_map(value, zerocon(type));
1352       builtin_throw(reason);
1353     }
1354   }
1355 
1356   // Must throw exception, fall-thru not possible?
1357   if (stopped()) {
1358     return top();               // No result
1359   }
1360 
1361   if (assert_null) {
1362     // Cast obj to null on this path.
1363     replace_in_map(value, zerocon(type));
1364     return zerocon(type);
1365   }
1366 
1367   // Cast obj to not-null on this path, if there is no null_control.
1368   // (If there is a null_control, a non-null value may come back to haunt us.)
1369   if (type == T_OBJECT) {
1370     Node* cast = cast_not_null(value, false);
1371     if (null_control == NULL || (*null_control) == top())
1372       replace_in_map(value, cast);
1373     value = cast;
1374   }
1375 
1376   return value;
1377 }
1378 
1379 
1380 //------------------------------cast_not_null----------------------------------
1381 // Cast obj to not-null on this path
1382 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1383   const Type *t = _gvn.type(obj);
1384   const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1385   // Object is already not-null?
1386   if( t == t_not_null ) return obj;
1387 
1388   Node *cast = new CastPPNode(obj,t_not_null);
1389   cast->init_req(0, control());
1390   cast = _gvn.transform( cast );
1391 
1392   // Scan for instances of 'obj' in the current JVM mapping.
1393   // These instances are known to be not-null after the test.
1394   if (do_replace_in_map)
1395     replace_in_map(obj, cast);
1396 
1397   return cast;                  // Return casted value
1398 }
1399 
1400 // Sometimes in intrinsics, we implicitly know an object is not null
1401 // (there's no actual null check) so we can cast it to not null. In
1402 // the course of optimizations, the input to the cast can become null.
1403 // In that case that data path will die and we need the control path
1404 // to become dead as well to keep the graph consistent. So we have to
1405 // add a check for null for which one branch can't be taken. It uses
1406 // an Opaque4 node that will cause the check to be removed after loop
1407 // opts so the test goes away and the compiled code doesn't execute a
1408 // useless check.
1409 Node* GraphKit::must_be_not_null(Node* value, bool do_replace_in_map) {
1410   Node* chk = _gvn.transform(new CmpPNode(value, null()));
1411   Node *tst = _gvn.transform(new BoolNode(chk, BoolTest::ne));
1412   Node* opaq = _gvn.transform(new Opaque4Node(C, tst, intcon(1)));
1413   IfNode *iff = new IfNode(control(), opaq, PROB_MAX, COUNT_UNKNOWN);
1414   _gvn.set_type(iff, iff->Value(&_gvn));
1415   Node *if_f = _gvn.transform(new IfFalseNode(iff));
1416   Node *frame = _gvn.transform(new ParmNode(C->start(), TypeFunc::FramePtr));
1417   Node *halt = _gvn.transform(new HaltNode(if_f, frame));
1418   C->root()->add_req(halt);
1419   Node *if_t = _gvn.transform(new IfTrueNode(iff));
1420   set_control(if_t);
1421   return cast_not_null(value, do_replace_in_map);
1422 }
1423 
1424 
1425 //--------------------------replace_in_map-------------------------------------
1426 void GraphKit::replace_in_map(Node* old, Node* neww) {
1427   if (old == neww) {
1428     return;
1429   }
1430 
1431   map()->replace_edge(old, neww);
1432 
1433   // Note: This operation potentially replaces any edge
1434   // on the map.  This includes locals, stack, and monitors
1435   // of the current (innermost) JVM state.
1436 
1437   // don't let inconsistent types from profiling escape this
1438   // method
1439 
1440   const Type* told = _gvn.type(old);
1441   const Type* tnew = _gvn.type(neww);
1442 
1443   if (!tnew->higher_equal(told)) {
1444     return;
1445   }
1446 
1447   map()->record_replaced_node(old, neww);
1448 }
1449 
1450 
1451 //=============================================================================
1452 //--------------------------------memory---------------------------------------
1453 Node* GraphKit::memory(uint alias_idx) {
1454   MergeMemNode* mem = merged_memory();
1455   Node* p = mem->memory_at(alias_idx);
1456   _gvn.set_type(p, Type::MEMORY);  // must be mapped
1457   return p;
1458 }
1459 
1460 //-----------------------------reset_memory------------------------------------
1461 Node* GraphKit::reset_memory() {
1462   Node* mem = map()->memory();
1463   // do not use this node for any more parsing!
1464   debug_only( map()->set_memory((Node*)NULL) );
1465   return _gvn.transform( mem );
1466 }
1467 
1468 //------------------------------set_all_memory---------------------------------
1469 void GraphKit::set_all_memory(Node* newmem) {
1470   Node* mergemem = MergeMemNode::make(newmem);
1471   gvn().set_type_bottom(mergemem);
1472   map()->set_memory(mergemem);
1473 }
1474 
1475 //------------------------------set_all_memory_call----------------------------
1476 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1477   Node* newmem = _gvn.transform( new ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1478   set_all_memory(newmem);
1479 }
1480 
1481 //=============================================================================
1482 //
1483 // parser factory methods for MemNodes
1484 //
1485 // These are layered on top of the factory methods in LoadNode and StoreNode,
1486 // and integrate with the parser's memory state and _gvn engine.
1487 //
1488 
1489 // factory methods in "int adr_idx"
1490 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1491                           int adr_idx,
1492                           MemNode::MemOrd mo,
1493                           LoadNode::ControlDependency control_dependency,
1494                           bool require_atomic_access,
1495                           bool unaligned,
1496                           bool mismatched,
1497                           bool unsafe) {
1498   assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1499   const TypePtr* adr_type = NULL; // debug-mode-only argument
1500   debug_only(adr_type = C->get_adr_type(adr_idx));
1501   Node* mem = memory(adr_idx);
1502   Node* ld;
1503   if (require_atomic_access && bt == T_LONG) {
1504     ld = LoadLNode::make_atomic(ctl, mem, adr, adr_type, t, mo, control_dependency, unaligned, mismatched, unsafe);
1505   } else if (require_atomic_access && bt == T_DOUBLE) {
1506     ld = LoadDNode::make_atomic(ctl, mem, adr, adr_type, t, mo, control_dependency, unaligned, mismatched, unsafe);
1507   } else {
1508     ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, unaligned, mismatched, unsafe);
1509   }
1510   ld = _gvn.transform(ld);
1511   if (((bt == T_OBJECT) && C->do_escape_analysis()) || C->eliminate_boxing()) {
1512     // Improve graph before escape analysis and boxing elimination.
1513     record_for_igvn(ld);
1514   }
1515   return ld;
1516 }
1517 
1518 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1519                                 int adr_idx,
1520                                 MemNode::MemOrd mo,
1521                                 bool require_atomic_access,
1522                                 bool unaligned,
1523                                 bool mismatched,
1524                                 bool unsafe) {
1525   assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1526   const TypePtr* adr_type = NULL;
1527   debug_only(adr_type = C->get_adr_type(adr_idx));
1528   Node *mem = memory(adr_idx);
1529   Node* st;
1530   if (require_atomic_access && bt == T_LONG) {
1531     st = StoreLNode::make_atomic(ctl, mem, adr, adr_type, val, mo);
1532   } else if (require_atomic_access && bt == T_DOUBLE) {
1533     st = StoreDNode::make_atomic(ctl, mem, adr, adr_type, val, mo);
1534   } else {
1535     st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo);
1536   }
1537   if (unaligned) {
1538     st->as_Store()->set_unaligned_access();
1539   }
1540   if (mismatched) {
1541     st->as_Store()->set_mismatched_access();
1542   }
1543   if (unsafe) {
1544     st->as_Store()->set_unsafe_access();
1545   }
1546   st = _gvn.transform(st);
1547   set_memory(st, adr_idx);
1548   // Back-to-back stores can only remove intermediate store with DU info
1549   // so push on worklist for optimizer.
1550   if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1551     record_for_igvn(st);
1552 
1553   return st;
1554 }
1555 
1556 Node* GraphKit::access_store_at(Node* ctl,
1557                                 Node* obj,
1558                                 Node* adr,
1559                                 const TypePtr* adr_type,
1560                                 Node* val,
1561                                 const Type* val_type,
1562                                 BasicType bt,
1563                                 DecoratorSet decorators) {
1564   // Transformation of a value which could be NULL pointer (CastPP #NULL)
1565   // could be delayed during Parse (for example, in adjust_map_after_if()).
1566   // Execute transformation here to avoid barrier generation in such case.
1567   if (_gvn.type(val) == TypePtr::NULL_PTR) {
1568     val = _gvn.makecon(TypePtr::NULL_PTR);
1569   }
1570 
1571   set_control(ctl);
1572   if (stopped()) {
1573     return top(); // Dead path ?
1574   }
1575 
1576   assert(val != NULL, "not dead path");
1577 
1578   C2AccessValuePtr addr(adr, adr_type);
1579   C2AccessValue value(val, val_type);
1580   C2Access access(this, decorators | C2_WRITE_ACCESS, bt, obj, addr);
1581   if (access.is_raw()) {
1582     return _barrier_set->BarrierSetC2::store_at(access, value);
1583   } else {
1584     return _barrier_set->store_at(access, value);
1585   }
1586 }
1587 
1588 Node* GraphKit::access_load_at(Node* obj,   // containing obj
1589                                Node* adr,   // actual adress to store val at
1590                                const TypePtr* adr_type,
1591                                const Type* val_type,
1592                                BasicType bt,
1593                                DecoratorSet decorators) {
1594   if (stopped()) {
1595     return top(); // Dead path ?
1596   }
1597 
1598   C2AccessValuePtr addr(adr, adr_type);
1599   C2Access access(this, decorators | C2_READ_ACCESS, bt, obj, addr);
1600   if (access.is_raw()) {
1601     return _barrier_set->BarrierSetC2::load_at(access, val_type);
1602   } else {
1603     return _barrier_set->load_at(access, val_type);
1604   }
1605 }
1606 
1607 Node* GraphKit::access_atomic_cmpxchg_val_at(Node* ctl,
1608                                              Node* obj,
1609                                              Node* adr,
1610                                              const TypePtr* adr_type,
1611                                              int alias_idx,
1612                                              Node* expected_val,
1613                                              Node* new_val,
1614                                              const Type* value_type,
1615                                              BasicType bt,
1616                                              DecoratorSet decorators) {
1617   set_control(ctl);
1618   C2AccessValuePtr addr(adr, adr_type);
1619   C2AtomicAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1620                         bt, obj, addr, alias_idx);
1621   if (access.is_raw()) {
1622     return _barrier_set->BarrierSetC2::atomic_cmpxchg_val_at(access, expected_val, new_val, value_type);
1623   } else {
1624     return _barrier_set->atomic_cmpxchg_val_at(access, expected_val, new_val, value_type);
1625   }
1626 }
1627 
1628 Node* GraphKit::access_atomic_cmpxchg_bool_at(Node* ctl,
1629                                               Node* obj,
1630                                               Node* adr,
1631                                               const TypePtr* adr_type,
1632                                               int alias_idx,
1633                                               Node* expected_val,
1634                                               Node* new_val,
1635                                               const Type* value_type,
1636                                               BasicType bt,
1637                                               DecoratorSet decorators) {
1638   set_control(ctl);
1639   C2AccessValuePtr addr(adr, adr_type);
1640   C2AtomicAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1641                         bt, obj, addr, alias_idx);
1642   if (access.is_raw()) {
1643     return _barrier_set->BarrierSetC2::atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type);
1644   } else {
1645     return _barrier_set->atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type);
1646   }
1647 }
1648 
1649 Node* GraphKit::access_atomic_xchg_at(Node* ctl,
1650                                       Node* obj,
1651                                       Node* adr,
1652                                       const TypePtr* adr_type,
1653                                       int alias_idx,
1654                                       Node* new_val,
1655                                       const Type* value_type,
1656                                       BasicType bt,
1657                                       DecoratorSet decorators) {
1658   set_control(ctl);
1659   C2AccessValuePtr addr(adr, adr_type);
1660   C2AtomicAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1661                         bt, obj, addr, alias_idx);
1662   if (access.is_raw()) {
1663     return _barrier_set->BarrierSetC2::atomic_xchg_at(access, new_val, value_type);
1664   } else {
1665     return _barrier_set->atomic_xchg_at(access, new_val, value_type);
1666   }
1667 }
1668 
1669 Node* GraphKit::access_atomic_add_at(Node* ctl,
1670                                      Node* obj,
1671                                      Node* adr,
1672                                      const TypePtr* adr_type,
1673                                      int alias_idx,
1674                                      Node* new_val,
1675                                      const Type* value_type,
1676                                      BasicType bt,
1677                                      DecoratorSet decorators) {
1678   set_control(ctl);
1679   C2AccessValuePtr addr(adr, adr_type);
1680   C2AtomicAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS, bt, obj, addr, alias_idx);
1681   if (access.is_raw()) {
1682     return _barrier_set->BarrierSetC2::atomic_add_at(access, new_val, value_type);
1683   } else {
1684     return _barrier_set->atomic_add_at(access, new_val, value_type);
1685   }
1686 }
1687 
1688 void GraphKit::access_clone(Node* ctl, Node* src, Node* dst, Node* size, bool is_array) {
1689   set_control(ctl);
1690   return _barrier_set->clone(this, src, dst, size, is_array);
1691 }
1692 
1693 //-------------------------array_element_address-------------------------
1694 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1695                                       const TypeInt* sizetype, Node* ctrl) {
1696   uint shift  = exact_log2(type2aelembytes(elembt));
1697   uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1698 
1699   // short-circuit a common case (saves lots of confusing waste motion)
1700   jint idx_con = find_int_con(idx, -1);
1701   if (idx_con >= 0) {
1702     intptr_t offset = header + ((intptr_t)idx_con << shift);
1703     return basic_plus_adr(ary, offset);
1704   }
1705 
1706   // must be correct type for alignment purposes
1707   Node* base  = basic_plus_adr(ary, header);
1708   idx = Compile::conv_I2X_index(&_gvn, idx, sizetype, ctrl);
1709   Node* scale = _gvn.transform( new LShiftXNode(idx, intcon(shift)) );
1710   return basic_plus_adr(ary, base, scale);
1711 }
1712 
1713 //-------------------------load_array_element-------------------------
1714 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) {
1715   const Type* elemtype = arytype->elem();
1716   BasicType elembt = elemtype->array_element_basic_type();
1717   Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1718   if (elembt == T_NARROWOOP) {
1719     elembt = T_OBJECT; // To satisfy switch in LoadNode::make()
1720   }
1721   Node* ld = make_load(ctl, adr, elemtype, elembt, arytype, MemNode::unordered);
1722   return ld;
1723 }
1724 
1725 //-------------------------set_arguments_for_java_call-------------------------
1726 // Arguments (pre-popped from the stack) are taken from the JVMS.
1727 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1728   // Add the call arguments:
1729   uint nargs = call->method()->arg_size();
1730   for (uint i = 0; i < nargs; i++) {
1731     Node* arg = argument(i);
1732     call->init_req(i + TypeFunc::Parms, arg);
1733   }
1734 }
1735 
1736 //---------------------------set_edges_for_java_call---------------------------
1737 // Connect a newly created call into the current JVMS.
1738 // A return value node (if any) is returned from set_edges_for_java_call.
1739 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1740 
1741   // Add the predefined inputs:
1742   call->init_req( TypeFunc::Control, control() );
1743   call->init_req( TypeFunc::I_O    , i_o() );
1744   call->init_req( TypeFunc::Memory , reset_memory() );
1745   call->init_req( TypeFunc::FramePtr, frameptr() );
1746   call->init_req( TypeFunc::ReturnAdr, top() );
1747 
1748   add_safepoint_edges(call, must_throw);
1749 
1750   Node* xcall = _gvn.transform(call);
1751 
1752   if (xcall == top()) {
1753     set_control(top());
1754     return;
1755   }
1756   assert(xcall == call, "call identity is stable");
1757 
1758   // Re-use the current map to produce the result.
1759 
1760   set_control(_gvn.transform(new ProjNode(call, TypeFunc::Control)));
1761   set_i_o(    _gvn.transform(new ProjNode(call, TypeFunc::I_O    , separate_io_proj)));
1762   set_all_memory_call(xcall, separate_io_proj);
1763 
1764   //return xcall;   // no need, caller already has it
1765 }
1766 
1767 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) {
1768   if (stopped())  return top();  // maybe the call folded up?
1769 
1770   // Capture the return value, if any.
1771   Node* ret;
1772   if (call->method() == NULL ||
1773       call->method()->return_type()->basic_type() == T_VOID)
1774         ret = top();
1775   else  ret = _gvn.transform(new ProjNode(call, TypeFunc::Parms));
1776 
1777   // Note:  Since any out-of-line call can produce an exception,
1778   // we always insert an I_O projection from the call into the result.
1779 
1780   make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj);
1781 
1782   if (separate_io_proj) {
1783     // The caller requested separate projections be used by the fall
1784     // through and exceptional paths, so replace the projections for
1785     // the fall through path.
1786     set_i_o(_gvn.transform( new ProjNode(call, TypeFunc::I_O) ));
1787     set_all_memory(_gvn.transform( new ProjNode(call, TypeFunc::Memory) ));
1788   }
1789   return ret;
1790 }
1791 
1792 //--------------------set_predefined_input_for_runtime_call--------------------
1793 // Reading and setting the memory state is way conservative here.
1794 // The real problem is that I am not doing real Type analysis on memory,
1795 // so I cannot distinguish card mark stores from other stores.  Across a GC
1796 // point the Store Barrier and the card mark memory has to agree.  I cannot
1797 // have a card mark store and its barrier split across the GC point from
1798 // either above or below.  Here I get that to happen by reading ALL of memory.
1799 // A better answer would be to separate out card marks from other memory.
1800 // For now, return the input memory state, so that it can be reused
1801 // after the call, if this call has restricted memory effects.
1802 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call, Node* narrow_mem) {
1803   // Set fixed predefined input arguments
1804   Node* memory = reset_memory();
1805   Node* m = narrow_mem == NULL ? memory : narrow_mem;
1806   call->init_req( TypeFunc::Control,   control()  );
1807   call->init_req( TypeFunc::I_O,       top()      ); // does no i/o
1808   call->init_req( TypeFunc::Memory,    m          ); // may gc ptrs
1809   call->init_req( TypeFunc::FramePtr,  frameptr() );
1810   call->init_req( TypeFunc::ReturnAdr, top()      );
1811   return memory;
1812 }
1813 
1814 //-------------------set_predefined_output_for_runtime_call--------------------
1815 // Set control and memory (not i_o) from the call.
1816 // If keep_mem is not NULL, use it for the output state,
1817 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1818 // If hook_mem is NULL, this call produces no memory effects at all.
1819 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1820 // then only that memory slice is taken from the call.
1821 // In the last case, we must put an appropriate memory barrier before
1822 // the call, so as to create the correct anti-dependencies on loads
1823 // preceding the call.
1824 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1825                                                       Node* keep_mem,
1826                                                       const TypePtr* hook_mem) {
1827   // no i/o
1828   set_control(_gvn.transform( new ProjNode(call,TypeFunc::Control) ));
1829   if (keep_mem) {
1830     // First clone the existing memory state
1831     set_all_memory(keep_mem);
1832     if (hook_mem != NULL) {
1833       // Make memory for the call
1834       Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
1835       // Set the RawPtr memory state only.  This covers all the heap top/GC stuff
1836       // We also use hook_mem to extract specific effects from arraycopy stubs.
1837       set_memory(mem, hook_mem);
1838     }
1839     // ...else the call has NO memory effects.
1840 
1841     // Make sure the call advertises its memory effects precisely.
1842     // This lets us build accurate anti-dependences in gcm.cpp.
1843     assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1844            "call node must be constructed correctly");
1845   } else {
1846     assert(hook_mem == NULL, "");
1847     // This is not a "slow path" call; all memory comes from the call.
1848     set_all_memory_call(call);
1849   }
1850 }
1851 
1852 
1853 // Replace the call with the current state of the kit.
1854 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes) {
1855   JVMState* ejvms = NULL;
1856   if (has_exceptions()) {
1857     ejvms = transfer_exceptions_into_jvms();
1858   }
1859 
1860   ReplacedNodes replaced_nodes = map()->replaced_nodes();
1861   ReplacedNodes replaced_nodes_exception;
1862   Node* ex_ctl = top();
1863 
1864   SafePointNode* final_state = stop();
1865 
1866   // Find all the needed outputs of this call
1867   CallProjections callprojs;
1868   call->extract_projections(&callprojs, true);
1869 
1870   Node* init_mem = call->in(TypeFunc::Memory);
1871   Node* final_mem = final_state->in(TypeFunc::Memory);
1872   Node* final_ctl = final_state->in(TypeFunc::Control);
1873   Node* final_io = final_state->in(TypeFunc::I_O);
1874 
1875   // Replace all the old call edges with the edges from the inlining result
1876   if (callprojs.fallthrough_catchproj != NULL) {
1877     C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
1878   }
1879   if (callprojs.fallthrough_memproj != NULL) {
1880     if (final_mem->is_MergeMem()) {
1881       // Parser's exits MergeMem was not transformed but may be optimized
1882       final_mem = _gvn.transform(final_mem);
1883     }
1884     C->gvn_replace_by(callprojs.fallthrough_memproj,   final_mem);
1885   }
1886   if (callprojs.fallthrough_ioproj != NULL) {
1887     C->gvn_replace_by(callprojs.fallthrough_ioproj,    final_io);
1888   }
1889 
1890   // Replace the result with the new result if it exists and is used
1891   if (callprojs.resproj != NULL && result != NULL) {
1892     C->gvn_replace_by(callprojs.resproj, result);
1893   }
1894 
1895   if (ejvms == NULL) {
1896     // No exception edges to simply kill off those paths
1897     if (callprojs.catchall_catchproj != NULL) {
1898       C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1899     }
1900     if (callprojs.catchall_memproj != NULL) {
1901       C->gvn_replace_by(callprojs.catchall_memproj,   C->top());
1902     }
1903     if (callprojs.catchall_ioproj != NULL) {
1904       C->gvn_replace_by(callprojs.catchall_ioproj,    C->top());
1905     }
1906     // Replace the old exception object with top
1907     if (callprojs.exobj != NULL) {
1908       C->gvn_replace_by(callprojs.exobj, C->top());
1909     }
1910   } else {
1911     GraphKit ekit(ejvms);
1912 
1913     // Load my combined exception state into the kit, with all phis transformed:
1914     SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1915     replaced_nodes_exception = ex_map->replaced_nodes();
1916 
1917     Node* ex_oop = ekit.use_exception_state(ex_map);
1918 
1919     if (callprojs.catchall_catchproj != NULL) {
1920       C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1921       ex_ctl = ekit.control();
1922     }
1923     if (callprojs.catchall_memproj != NULL) {
1924       C->gvn_replace_by(callprojs.catchall_memproj,   ekit.reset_memory());
1925     }
1926     if (callprojs.catchall_ioproj != NULL) {
1927       C->gvn_replace_by(callprojs.catchall_ioproj,    ekit.i_o());
1928     }
1929 
1930     // Replace the old exception object with the newly created one
1931     if (callprojs.exobj != NULL) {
1932       C->gvn_replace_by(callprojs.exobj, ex_oop);
1933     }
1934   }
1935 
1936   // Disconnect the call from the graph
1937   call->disconnect_inputs(NULL, C);
1938   C->gvn_replace_by(call, C->top());
1939 
1940   // Clean up any MergeMems that feed other MergeMems since the
1941   // optimizer doesn't like that.
1942   if (final_mem->is_MergeMem()) {
1943     Node_List wl;
1944     for (SimpleDUIterator i(final_mem); i.has_next(); i.next()) {
1945       Node* m = i.get();
1946       if (m->is_MergeMem() && !wl.contains(m)) {
1947         wl.push(m);
1948       }
1949     }
1950     while (wl.size()  > 0) {
1951       _gvn.transform(wl.pop());
1952     }
1953   }
1954 
1955   if (callprojs.fallthrough_catchproj != NULL && !final_ctl->is_top() && do_replaced_nodes) {
1956     replaced_nodes.apply(C, final_ctl);
1957   }
1958   if (!ex_ctl->is_top() && do_replaced_nodes) {
1959     replaced_nodes_exception.apply(C, ex_ctl);
1960   }
1961 }
1962 
1963 
1964 //------------------------------increment_counter------------------------------
1965 // for statistics: increment a VM counter by 1
1966 
1967 void GraphKit::increment_counter(address counter_addr) {
1968   Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
1969   increment_counter(adr1);
1970 }
1971 
1972 void GraphKit::increment_counter(Node* counter_addr) {
1973   int adr_type = Compile::AliasIdxRaw;
1974   Node* ctrl = control();
1975   Node* cnt  = make_load(ctrl, counter_addr, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
1976   Node* incr = _gvn.transform(new AddINode(cnt, _gvn.intcon(1)));
1977   store_to_memory(ctrl, counter_addr, incr, T_INT, adr_type, MemNode::unordered);
1978 }
1979 
1980 
1981 //------------------------------uncommon_trap----------------------------------
1982 // Bail out to the interpreter in mid-method.  Implemented by calling the
1983 // uncommon_trap blob.  This helper function inserts a runtime call with the
1984 // right debug info.
1985 void GraphKit::uncommon_trap(int trap_request,
1986                              ciKlass* klass, const char* comment,
1987                              bool must_throw,
1988                              bool keep_exact_action) {
1989   if (failing())  stop();
1990   if (stopped())  return; // trap reachable?
1991 
1992   // Note:  If ProfileTraps is true, and if a deopt. actually
1993   // occurs here, the runtime will make sure an MDO exists.  There is
1994   // no need to call method()->ensure_method_data() at this point.
1995 
1996   // Set the stack pointer to the right value for reexecution:
1997   set_sp(reexecute_sp());
1998 
1999 #ifdef ASSERT
2000   if (!must_throw) {
2001     // Make sure the stack has at least enough depth to execute
2002     // the current bytecode.
2003     int inputs, ignored_depth;
2004     if (compute_stack_effects(inputs, ignored_depth)) {
2005       assert(sp() >= inputs, "must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
2006              Bytecodes::name(java_bc()), sp(), inputs);
2007     }
2008   }
2009 #endif
2010 
2011   Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
2012   Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
2013 
2014   switch (action) {
2015   case Deoptimization::Action_maybe_recompile:
2016   case Deoptimization::Action_reinterpret:
2017     // Temporary fix for 6529811 to allow virtual calls to be sure they
2018     // get the chance to go from mono->bi->mega
2019     if (!keep_exact_action &&
2020         Deoptimization::trap_request_index(trap_request) < 0 &&
2021         too_many_recompiles(reason)) {
2022       // This BCI is causing too many recompilations.
2023       if (C->log() != NULL) {
2024         C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'",
2025                 Deoptimization::trap_reason_name(reason),
2026                 Deoptimization::trap_action_name(action));
2027       }
2028       action = Deoptimization::Action_none;
2029       trap_request = Deoptimization::make_trap_request(reason, action);
2030     } else {
2031       C->set_trap_can_recompile(true);
2032     }
2033     break;
2034   case Deoptimization::Action_make_not_entrant:
2035     C->set_trap_can_recompile(true);
2036     break;
2037   case Deoptimization::Action_none:
2038   case Deoptimization::Action_make_not_compilable:
2039     break;
2040   default:
2041 #ifdef ASSERT
2042     fatal("unknown action %d: %s", action, Deoptimization::trap_action_name(action));
2043 #endif
2044     break;
2045   }
2046 
2047   if (TraceOptoParse) {
2048     char buf[100];
2049     tty->print_cr("Uncommon trap %s at bci:%d",
2050                   Deoptimization::format_trap_request(buf, sizeof(buf),
2051                                                       trap_request), bci());
2052   }
2053 
2054   CompileLog* log = C->log();
2055   if (log != NULL) {
2056     int kid = (klass == NULL)? -1: log->identify(klass);
2057     log->begin_elem("uncommon_trap bci='%d'", bci());
2058     char buf[100];
2059     log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2060                                                           trap_request));
2061     if (kid >= 0)         log->print(" klass='%d'", kid);
2062     if (comment != NULL)  log->print(" comment='%s'", comment);
2063     log->end_elem();
2064   }
2065 
2066   // Make sure any guarding test views this path as very unlikely
2067   Node *i0 = control()->in(0);
2068   if (i0 != NULL && i0->is_If()) {        // Found a guarding if test?
2069     IfNode *iff = i0->as_If();
2070     float f = iff->_prob;   // Get prob
2071     if (control()->Opcode() == Op_IfTrue) {
2072       if (f > PROB_UNLIKELY_MAG(4))
2073         iff->_prob = PROB_MIN;
2074     } else {
2075       if (f < PROB_LIKELY_MAG(4))
2076         iff->_prob = PROB_MAX;
2077     }
2078   }
2079 
2080   // Clear out dead values from the debug info.
2081   kill_dead_locals();
2082 
2083   // Now insert the uncommon trap subroutine call
2084   address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point();
2085   const TypePtr* no_memory_effects = NULL;
2086   // Pass the index of the class to be loaded
2087   Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2088                                  (must_throw ? RC_MUST_THROW : 0),
2089                                  OptoRuntime::uncommon_trap_Type(),
2090                                  call_addr, "uncommon_trap", no_memory_effects,
2091                                  intcon(trap_request));
2092   assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2093          "must extract request correctly from the graph");
2094   assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2095 
2096   call->set_req(TypeFunc::ReturnAdr, returnadr());
2097   // The debug info is the only real input to this call.
2098 
2099   // Halt-and-catch fire here.  The above call should never return!
2100   HaltNode* halt = new HaltNode(control(), frameptr());
2101   _gvn.set_type_bottom(halt);
2102   root()->add_req(halt);
2103 
2104   stop_and_kill_map();
2105 }
2106 
2107 
2108 //--------------------------just_allocated_object------------------------------
2109 // Report the object that was just allocated.
2110 // It must be the case that there are no intervening safepoints.
2111 // We use this to determine if an object is so "fresh" that
2112 // it does not require card marks.
2113 Node* GraphKit::just_allocated_object(Node* current_control) {
2114   if (C->recent_alloc_ctl() == current_control)
2115     return C->recent_alloc_obj();
2116   return NULL;
2117 }
2118 
2119 
2120 void GraphKit::round_double_arguments(ciMethod* dest_method) {
2121   // (Note:  TypeFunc::make has a cache that makes this fast.)
2122   const TypeFunc* tf    = TypeFunc::make(dest_method);
2123   int             nargs = tf->domain()->cnt() - TypeFunc::Parms;
2124   for (int j = 0; j < nargs; j++) {
2125     const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2126     if( targ->basic_type() == T_DOUBLE ) {
2127       // If any parameters are doubles, they must be rounded before
2128       // the call, dstore_rounding does gvn.transform
2129       Node *arg = argument(j);
2130       arg = dstore_rounding(arg);
2131       set_argument(j, arg);
2132     }
2133   }
2134 }
2135 
2136 /**
2137  * Record profiling data exact_kls for Node n with the type system so
2138  * that it can propagate it (speculation)
2139  *
2140  * @param n          node that the type applies to
2141  * @param exact_kls  type from profiling
2142  * @param maybe_null did profiling see null?
2143  *
2144  * @return           node with improved type
2145  */
2146 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind) {
2147   const Type* current_type = _gvn.type(n);
2148   assert(UseTypeSpeculation, "type speculation must be on");
2149 
2150   const TypePtr* speculative = current_type->speculative();
2151 
2152   // Should the klass from the profile be recorded in the speculative type?
2153   if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2154     const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls);
2155     const TypeOopPtr* xtype = tklass->as_instance_type();
2156     assert(xtype->klass_is_exact(), "Should be exact");
2157     // Any reason to believe n is not null (from this profiling or a previous one)?
2158     assert(ptr_kind != ProfileAlwaysNull, "impossible here");
2159     const TypePtr* ptr = (ptr_kind == ProfileMaybeNull && current_type->speculative_maybe_null()) ? TypePtr::BOTTOM : TypePtr::NOTNULL;
2160     // record the new speculative type's depth
2161     speculative = xtype->cast_to_ptr_type(ptr->ptr())->is_ptr();
2162     speculative = speculative->with_inline_depth(jvms()->depth());
2163   } else if (current_type->would_improve_ptr(ptr_kind)) {
2164     // Profiling report that null was never seen so we can change the
2165     // speculative type to non null ptr.
2166     if (ptr_kind == ProfileAlwaysNull) {
2167       speculative = TypePtr::NULL_PTR;
2168     } else {
2169       assert(ptr_kind == ProfileNeverNull, "nothing else is an improvement");
2170       const TypePtr* ptr = TypePtr::NOTNULL;
2171       if (speculative != NULL) {
2172         speculative = speculative->cast_to_ptr_type(ptr->ptr())->is_ptr();
2173       } else {
2174         speculative = ptr;
2175       }
2176     }
2177   }
2178 
2179   if (speculative != current_type->speculative()) {
2180     // Build a type with a speculative type (what we think we know
2181     // about the type but will need a guard when we use it)
2182     const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2183     // We're changing the type, we need a new CheckCast node to carry
2184     // the new type. The new type depends on the control: what
2185     // profiling tells us is only valid from here as far as we can
2186     // tell.
2187     Node* cast = new CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2188     cast = _gvn.transform(cast);
2189     replace_in_map(n, cast);
2190     n = cast;
2191   }
2192 
2193   return n;
2194 }
2195 
2196 /**
2197  * Record profiling data from receiver profiling at an invoke with the
2198  * type system so that it can propagate it (speculation)
2199  *
2200  * @param n  receiver node
2201  *
2202  * @return   node with improved type
2203  */
2204 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2205   if (!UseTypeSpeculation) {
2206     return n;
2207   }
2208   ciKlass* exact_kls = profile_has_unique_klass();
2209   ProfilePtrKind ptr_kind = ProfileMaybeNull;
2210   if ((java_bc() == Bytecodes::_checkcast ||
2211        java_bc() == Bytecodes::_instanceof ||
2212        java_bc() == Bytecodes::_aastore) &&
2213       method()->method_data()->is_mature()) {
2214     ciProfileData* data = method()->method_data()->bci_to_data(bci());
2215     if (data != NULL) {
2216       if (!data->as_BitData()->null_seen()) {
2217         ptr_kind = ProfileNeverNull;
2218       } else {
2219         assert(data->is_ReceiverTypeData(), "bad profile data type");
2220         ciReceiverTypeData* call = (ciReceiverTypeData*)data->as_ReceiverTypeData();
2221         uint i = 0;
2222         for (; i < call->row_limit(); i++) {
2223           ciKlass* receiver = call->receiver(i);
2224           if (receiver != NULL) {
2225             break;
2226           }
2227         }
2228         ptr_kind = (i == call->row_limit()) ? ProfileAlwaysNull : ProfileMaybeNull;
2229       }
2230     }
2231   }
2232   return record_profile_for_speculation(n, exact_kls, ptr_kind);
2233 }
2234 
2235 /**
2236  * Record profiling data from argument profiling at an invoke with the
2237  * type system so that it can propagate it (speculation)
2238  *
2239  * @param dest_method  target method for the call
2240  * @param bc           what invoke bytecode is this?
2241  */
2242 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2243   if (!UseTypeSpeculation) {
2244     return;
2245   }
2246   const TypeFunc* tf    = TypeFunc::make(dest_method);
2247   int             nargs = tf->domain()->cnt() - TypeFunc::Parms;
2248   int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2249   for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2250     const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2251     if (targ->basic_type() == T_OBJECT || targ->basic_type() == T_ARRAY) {
2252       ProfilePtrKind ptr_kind = ProfileMaybeNull;
2253       ciKlass* better_type = NULL;
2254       if (method()->argument_profiled_type(bci(), i, better_type, ptr_kind)) {
2255         record_profile_for_speculation(argument(j), better_type, ptr_kind);
2256       }
2257       i++;
2258     }
2259   }
2260 }
2261 
2262 /**
2263  * Record profiling data from parameter profiling at an invoke with
2264  * the type system so that it can propagate it (speculation)
2265  */
2266 void GraphKit::record_profiled_parameters_for_speculation() {
2267   if (!UseTypeSpeculation) {
2268     return;
2269   }
2270   for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2271     if (_gvn.type(local(i))->isa_oopptr()) {
2272       ProfilePtrKind ptr_kind = ProfileMaybeNull;
2273       ciKlass* better_type = NULL;
2274       if (method()->parameter_profiled_type(j, better_type, ptr_kind)) {
2275         record_profile_for_speculation(local(i), better_type, ptr_kind);
2276       }
2277       j++;
2278     }
2279   }
2280 }
2281 
2282 /**
2283  * Record profiling data from return value profiling at an invoke with
2284  * the type system so that it can propagate it (speculation)
2285  */
2286 void GraphKit::record_profiled_return_for_speculation() {
2287   if (!UseTypeSpeculation) {
2288     return;
2289   }
2290   ProfilePtrKind ptr_kind = ProfileMaybeNull;
2291   ciKlass* better_type = NULL;
2292   if (method()->return_profiled_type(bci(), better_type, ptr_kind)) {
2293     // If profiling reports a single type for the return value,
2294     // feed it to the type system so it can propagate it as a
2295     // speculative type
2296     record_profile_for_speculation(stack(sp()-1), better_type, ptr_kind);
2297   }
2298 }
2299 
2300 void GraphKit::round_double_result(ciMethod* dest_method) {
2301   // A non-strict method may return a double value which has an extended
2302   // exponent, but this must not be visible in a caller which is 'strict'
2303   // If a strict caller invokes a non-strict callee, round a double result
2304 
2305   BasicType result_type = dest_method->return_type()->basic_type();
2306   assert( method() != NULL, "must have caller context");
2307   if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) {
2308     // Destination method's return value is on top of stack
2309     // dstore_rounding() does gvn.transform
2310     Node *result = pop_pair();
2311     result = dstore_rounding(result);
2312     push_pair(result);
2313   }
2314 }
2315 
2316 // rounding for strict float precision conformance
2317 Node* GraphKit::precision_rounding(Node* n) {
2318   return UseStrictFP && _method->flags().is_strict()
2319     && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding
2320     ? _gvn.transform( new RoundFloatNode(0, n) )
2321     : n;
2322 }
2323 
2324 // rounding for strict double precision conformance
2325 Node* GraphKit::dprecision_rounding(Node *n) {
2326   return UseStrictFP && _method->flags().is_strict()
2327     && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding
2328     ? _gvn.transform( new RoundDoubleNode(0, n) )
2329     : n;
2330 }
2331 
2332 // rounding for non-strict double stores
2333 Node* GraphKit::dstore_rounding(Node* n) {
2334   return Matcher::strict_fp_requires_explicit_rounding
2335     && UseSSE <= 1
2336     ? _gvn.transform( new RoundDoubleNode(0, n) )
2337     : n;
2338 }
2339 
2340 //=============================================================================
2341 // Generate a fast path/slow path idiom.  Graph looks like:
2342 // [foo] indicates that 'foo' is a parameter
2343 //
2344 //              [in]     NULL
2345 //                 \    /
2346 //                  CmpP
2347 //                  Bool ne
2348 //                   If
2349 //                  /  \
2350 //              True    False-<2>
2351 //              / |
2352 //             /  cast_not_null
2353 //           Load  |    |   ^
2354 //        [fast_test]   |   |
2355 // gvn to   opt_test    |   |
2356 //          /    \      |  <1>
2357 //      True     False  |
2358 //        |         \\  |
2359 //   [slow_call]     \[fast_result]
2360 //    Ctl   Val       \      \
2361 //     |               \      \
2362 //    Catch       <1>   \      \
2363 //   /    \        ^     \      \
2364 //  Ex    No_Ex    |      \      \
2365 //  |       \   \  |       \ <2>  \
2366 //  ...      \  [slow_res] |  |    \   [null_result]
2367 //            \         \--+--+---  |  |
2368 //             \           | /    \ | /
2369 //              --------Region     Phi
2370 //
2371 //=============================================================================
2372 // Code is structured as a series of driver functions all called 'do_XXX' that
2373 // call a set of helper functions.  Helper functions first, then drivers.
2374 
2375 //------------------------------null_check_oop---------------------------------
2376 // Null check oop.  Set null-path control into Region in slot 3.
2377 // Make a cast-not-nullness use the other not-null control.  Return cast.
2378 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2379                                bool never_see_null,
2380                                bool safe_for_replace,
2381                                bool speculative) {
2382   // Initial NULL check taken path
2383   (*null_control) = top();
2384   Node* cast = null_check_common(value, T_OBJECT, false, null_control, speculative);
2385 
2386   // Generate uncommon_trap:
2387   if (never_see_null && (*null_control) != top()) {
2388     // If we see an unexpected null at a check-cast we record it and force a
2389     // recompile; the offending check-cast will be compiled to handle NULLs.
2390     // If we see more than one offending BCI, then all checkcasts in the
2391     // method will be compiled to handle NULLs.
2392     PreserveJVMState pjvms(this);
2393     set_control(*null_control);
2394     replace_in_map(value, null());
2395     Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculative);
2396     uncommon_trap(reason,
2397                   Deoptimization::Action_make_not_entrant);
2398     (*null_control) = top();    // NULL path is dead
2399   }
2400   if ((*null_control) == top() && safe_for_replace) {
2401     replace_in_map(value, cast);
2402   }
2403 
2404   // Cast away null-ness on the result
2405   return cast;
2406 }
2407 
2408 //------------------------------opt_iff----------------------------------------
2409 // Optimize the fast-check IfNode.  Set the fast-path region slot 2.
2410 // Return slow-path control.
2411 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2412   IfNode *opt_iff = _gvn.transform(iff)->as_If();
2413 
2414   // Fast path taken; set region slot 2
2415   Node *fast_taken = _gvn.transform( new IfFalseNode(opt_iff) );
2416   region->init_req(2,fast_taken); // Capture fast-control
2417 
2418   // Fast path not-taken, i.e. slow path
2419   Node *slow_taken = _gvn.transform( new IfTrueNode(opt_iff) );
2420   return slow_taken;
2421 }
2422 
2423 //-----------------------------make_runtime_call-------------------------------
2424 Node* GraphKit::make_runtime_call(int flags,
2425                                   const TypeFunc* call_type, address call_addr,
2426                                   const char* call_name,
2427                                   const TypePtr* adr_type,
2428                                   // The following parms are all optional.
2429                                   // The first NULL ends the list.
2430                                   Node* parm0, Node* parm1,
2431                                   Node* parm2, Node* parm3,
2432                                   Node* parm4, Node* parm5,
2433                                   Node* parm6, Node* parm7) {
2434   assert(call_addr != NULL, "must not call NULL targets");
2435 
2436   // Slow-path call
2437   bool is_leaf = !(flags & RC_NO_LEAF);
2438   bool has_io  = (!is_leaf && !(flags & RC_NO_IO));
2439   if (call_name == NULL) {
2440     assert(!is_leaf, "must supply name for leaf");
2441     call_name = OptoRuntime::stub_name(call_addr);
2442   }
2443   CallNode* call;
2444   if (!is_leaf) {
2445     call = new CallStaticJavaNode(call_type, call_addr, call_name,
2446                                            bci(), adr_type);
2447   } else if (flags & RC_NO_FP) {
2448     call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2449   } else {
2450     call = new CallLeafNode(call_type, call_addr, call_name, adr_type);
2451   }
2452 
2453   // The following is similar to set_edges_for_java_call,
2454   // except that the memory effects of the call are restricted to AliasIdxRaw.
2455 
2456   // Slow path call has no side-effects, uses few values
2457   bool wide_in  = !(flags & RC_NARROW_MEM);
2458   bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2459 
2460   Node* prev_mem = NULL;
2461   if (wide_in) {
2462     prev_mem = set_predefined_input_for_runtime_call(call);
2463   } else {
2464     assert(!wide_out, "narrow in => narrow out");
2465     Node* narrow_mem = memory(adr_type);
2466     prev_mem = set_predefined_input_for_runtime_call(call, narrow_mem);
2467   }
2468 
2469   // Hook each parm in order.  Stop looking at the first NULL.
2470   if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0);
2471   if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1);
2472   if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2);
2473   if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3);
2474   if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4);
2475   if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5);
2476   if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6);
2477   if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7);
2478     /* close each nested if ===> */  } } } } } } } }
2479   assert(call->in(call->req()-1) != NULL, "must initialize all parms");
2480 
2481   if (!is_leaf) {
2482     // Non-leaves can block and take safepoints:
2483     add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2484   }
2485   // Non-leaves can throw exceptions:
2486   if (has_io) {
2487     call->set_req(TypeFunc::I_O, i_o());
2488   }
2489 
2490   if (flags & RC_UNCOMMON) {
2491     // Set the count to a tiny probability.  Cf. Estimate_Block_Frequency.
2492     // (An "if" probability corresponds roughly to an unconditional count.
2493     // Sort of.)
2494     call->set_cnt(PROB_UNLIKELY_MAG(4));
2495   }
2496 
2497   Node* c = _gvn.transform(call);
2498   assert(c == call, "cannot disappear");
2499 
2500   if (wide_out) {
2501     // Slow path call has full side-effects.
2502     set_predefined_output_for_runtime_call(call);
2503   } else {
2504     // Slow path call has few side-effects, and/or sets few values.
2505     set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2506   }
2507 
2508   if (has_io) {
2509     set_i_o(_gvn.transform(new ProjNode(call, TypeFunc::I_O)));
2510   }
2511   return call;
2512 
2513 }
2514 
2515 //------------------------------merge_memory-----------------------------------
2516 // Merge memory from one path into the current memory state.
2517 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2518   for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2519     Node* old_slice = mms.force_memory();
2520     Node* new_slice = mms.memory2();
2521     if (old_slice != new_slice) {
2522       PhiNode* phi;
2523       if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) {
2524         if (mms.is_empty()) {
2525           // clone base memory Phi's inputs for this memory slice
2526           assert(old_slice == mms.base_memory(), "sanity");
2527           phi = PhiNode::make(region, NULL, Type::MEMORY, mms.adr_type(C));
2528           _gvn.set_type(phi, Type::MEMORY);
2529           for (uint i = 1; i < phi->req(); i++) {
2530             phi->init_req(i, old_slice->in(i));
2531           }
2532         } else {
2533           phi = old_slice->as_Phi(); // Phi was generated already
2534         }
2535       } else {
2536         phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2537         _gvn.set_type(phi, Type::MEMORY);
2538       }
2539       phi->set_req(new_path, new_slice);
2540       mms.set_memory(phi);
2541     }
2542   }
2543 }
2544 
2545 //------------------------------make_slow_call_ex------------------------------
2546 // Make the exception handler hookups for the slow call
2547 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) {
2548   if (stopped())  return;
2549 
2550   // Make a catch node with just two handlers:  fall-through and catch-all
2551   Node* i_o  = _gvn.transform( new ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2552   Node* catc = _gvn.transform( new CatchNode(control(), i_o, 2) );
2553   Node* norm = _gvn.transform( new CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) );
2554   Node* excp = _gvn.transform( new CatchProjNode(catc, CatchProjNode::catch_all_index,    CatchProjNode::no_handler_bci) );
2555 
2556   { PreserveJVMState pjvms(this);
2557     set_control(excp);
2558     set_i_o(i_o);
2559 
2560     if (excp != top()) {
2561       if (deoptimize) {
2562         // Deoptimize if an exception is caught. Don't construct exception state in this case.
2563         uncommon_trap(Deoptimization::Reason_unhandled,
2564                       Deoptimization::Action_none);
2565       } else {
2566         // Create an exception state also.
2567         // Use an exact type if the caller has specified a specific exception.
2568         const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2569         Node*       ex_oop  = new CreateExNode(ex_type, control(), i_o);
2570         add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2571       }
2572     }
2573   }
2574 
2575   // Get the no-exception control from the CatchNode.
2576   set_control(norm);
2577 }
2578 
2579 static IfNode* gen_subtype_check_compare(Node* ctrl, Node* in1, Node* in2, BoolTest::mask test, float p, PhaseGVN* gvn, BasicType bt) {
2580   Node* cmp = NULL;
2581   switch(bt) {
2582   case T_INT: cmp = new CmpINode(in1, in2); break;
2583   case T_ADDRESS: cmp = new CmpPNode(in1, in2); break;
2584   default: fatal("unexpected comparison type %s", type2name(bt));
2585   }
2586   gvn->transform(cmp);
2587   Node* bol = gvn->transform(new BoolNode(cmp, test));
2588   IfNode* iff = new IfNode(ctrl, bol, p, COUNT_UNKNOWN);
2589   gvn->transform(iff);
2590   if (!bol->is_Con()) gvn->record_for_igvn(iff);
2591   return iff;
2592 }
2593 
2594 
2595 //-------------------------------gen_subtype_check-----------------------------
2596 // Generate a subtyping check.  Takes as input the subtype and supertype.
2597 // Returns 2 values: sets the default control() to the true path and returns
2598 // the false path.  Only reads invariant memory; sets no (visible) memory.
2599 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2600 // but that's not exposed to the optimizer.  This call also doesn't take in an
2601 // Object; if you wish to check an Object you need to load the Object's class
2602 // prior to coming here.
2603 Node* Phase::gen_subtype_check(Node* subklass, Node* superklass, Node** ctrl, MergeMemNode* mem, PhaseGVN* gvn) {
2604   Compile* C = gvn->C;
2605 
2606   if ((*ctrl)->is_top()) {
2607     return C->top();
2608   }
2609 
2610   // Fast check for identical types, perhaps identical constants.
2611   // The types can even be identical non-constants, in cases
2612   // involving Array.newInstance, Object.clone, etc.
2613   if (subklass == superklass)
2614     return C->top();             // false path is dead; no test needed.
2615 
2616   if (gvn->type(superklass)->singleton()) {
2617     ciKlass* superk = gvn->type(superklass)->is_klassptr()->klass();
2618     ciKlass* subk   = gvn->type(subklass)->is_klassptr()->klass();
2619 
2620     // In the common case of an exact superklass, try to fold up the
2621     // test before generating code.  You may ask, why not just generate
2622     // the code and then let it fold up?  The answer is that the generated
2623     // code will necessarily include null checks, which do not always
2624     // completely fold away.  If they are also needless, then they turn
2625     // into a performance loss.  Example:
2626     //    Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2627     // Here, the type of 'fa' is often exact, so the store check
2628     // of fa[1]=x will fold up, without testing the nullness of x.
2629     switch (C->static_subtype_check(superk, subk)) {
2630     case Compile::SSC_always_false:
2631       {
2632         Node* always_fail = *ctrl;
2633         *ctrl = gvn->C->top();
2634         return always_fail;
2635       }
2636     case Compile::SSC_always_true:
2637       return C->top();
2638     case Compile::SSC_easy_test:
2639       {
2640         // Just do a direct pointer compare and be done.
2641         IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_STATIC_FREQUENT, gvn, T_ADDRESS);
2642         *ctrl = gvn->transform(new IfTrueNode(iff));
2643         return gvn->transform(new IfFalseNode(iff));
2644       }
2645     case Compile::SSC_full_test:
2646       break;
2647     default:
2648       ShouldNotReachHere();
2649     }
2650   }
2651 
2652   // %%% Possible further optimization:  Even if the superklass is not exact,
2653   // if the subklass is the unique subtype of the superklass, the check
2654   // will always succeed.  We could leave a dependency behind to ensure this.
2655 
2656   // First load the super-klass's check-offset
2657   Node *p1 = gvn->transform(new AddPNode(superklass, superklass, gvn->MakeConX(in_bytes(Klass::super_check_offset_offset()))));
2658   Node* m = mem->memory_at(C->get_alias_index(gvn->type(p1)->is_ptr()));
2659   Node *chk_off = gvn->transform(new LoadINode(NULL, m, p1, gvn->type(p1)->is_ptr(), TypeInt::INT, MemNode::unordered));
2660   int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2661   bool might_be_cache = (gvn->find_int_con(chk_off, cacheoff_con) == cacheoff_con);
2662 
2663   // Load from the sub-klass's super-class display list, or a 1-word cache of
2664   // the secondary superclass list, or a failing value with a sentinel offset
2665   // if the super-klass is an interface or exceptionally deep in the Java
2666   // hierarchy and we have to scan the secondary superclass list the hard way.
2667   // Worst-case type is a little odd: NULL is allowed as a result (usually
2668   // klass loads can never produce a NULL).
2669   Node *chk_off_X = chk_off;
2670 #ifdef _LP64
2671   chk_off_X = gvn->transform(new ConvI2LNode(chk_off_X));
2672 #endif
2673   Node *p2 = gvn->transform(new AddPNode(subklass,subklass,chk_off_X));
2674   // For some types like interfaces the following loadKlass is from a 1-word
2675   // cache which is mutable so can't use immutable memory.  Other
2676   // types load from the super-class display table which is immutable.
2677   m = mem->memory_at(C->get_alias_index(gvn->type(p2)->is_ptr()));
2678   Node *kmem = might_be_cache ? m : C->immutable_memory();
2679   Node *nkls = gvn->transform(LoadKlassNode::make(*gvn, NULL, kmem, p2, gvn->type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL));
2680 
2681   // Compile speed common case: ARE a subtype and we canNOT fail
2682   if( superklass == nkls )
2683     return C->top();             // false path is dead; no test needed.
2684 
2685   // See if we get an immediate positive hit.  Happens roughly 83% of the
2686   // time.  Test to see if the value loaded just previously from the subklass
2687   // is exactly the superklass.
2688   IfNode *iff1 = gen_subtype_check_compare(*ctrl, superklass, nkls, BoolTest::eq, PROB_LIKELY(0.83f), gvn, T_ADDRESS);
2689   Node *iftrue1 = gvn->transform( new IfTrueNode (iff1));
2690   *ctrl = gvn->transform(new IfFalseNode(iff1));
2691 
2692   // Compile speed common case: Check for being deterministic right now.  If
2693   // chk_off is a constant and not equal to cacheoff then we are NOT a
2694   // subklass.  In this case we need exactly the 1 test above and we can
2695   // return those results immediately.
2696   if (!might_be_cache) {
2697     Node* not_subtype_ctrl = *ctrl;
2698     *ctrl = iftrue1; // We need exactly the 1 test above
2699     return not_subtype_ctrl;
2700   }
2701 
2702   // Gather the various success & failures here
2703   RegionNode *r_ok_subtype = new RegionNode(4);
2704   gvn->record_for_igvn(r_ok_subtype);
2705   RegionNode *r_not_subtype = new RegionNode(3);
2706   gvn->record_for_igvn(r_not_subtype);
2707 
2708   r_ok_subtype->init_req(1, iftrue1);
2709 
2710   // Check for immediate negative hit.  Happens roughly 11% of the time (which
2711   // is roughly 63% of the remaining cases).  Test to see if the loaded
2712   // check-offset points into the subklass display list or the 1-element
2713   // cache.  If it points to the display (and NOT the cache) and the display
2714   // missed then it's not a subtype.
2715   Node *cacheoff = gvn->intcon(cacheoff_con);
2716   IfNode *iff2 = gen_subtype_check_compare(*ctrl, chk_off, cacheoff, BoolTest::ne, PROB_LIKELY(0.63f), gvn, T_INT);
2717   r_not_subtype->init_req(1, gvn->transform(new IfTrueNode (iff2)));
2718   *ctrl = gvn->transform(new IfFalseNode(iff2));
2719 
2720   // Check for self.  Very rare to get here, but it is taken 1/3 the time.
2721   // No performance impact (too rare) but allows sharing of secondary arrays
2722   // which has some footprint reduction.
2723   IfNode *iff3 = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_LIKELY(0.36f), gvn, T_ADDRESS);
2724   r_ok_subtype->init_req(2, gvn->transform(new IfTrueNode(iff3)));
2725   *ctrl = gvn->transform(new IfFalseNode(iff3));
2726 
2727   // -- Roads not taken here: --
2728   // We could also have chosen to perform the self-check at the beginning
2729   // of this code sequence, as the assembler does.  This would not pay off
2730   // the same way, since the optimizer, unlike the assembler, can perform
2731   // static type analysis to fold away many successful self-checks.
2732   // Non-foldable self checks work better here in second position, because
2733   // the initial primary superclass check subsumes a self-check for most
2734   // types.  An exception would be a secondary type like array-of-interface,
2735   // which does not appear in its own primary supertype display.
2736   // Finally, we could have chosen to move the self-check into the
2737   // PartialSubtypeCheckNode, and from there out-of-line in a platform
2738   // dependent manner.  But it is worthwhile to have the check here,
2739   // where it can be perhaps be optimized.  The cost in code space is
2740   // small (register compare, branch).
2741 
2742   // Now do a linear scan of the secondary super-klass array.  Again, no real
2743   // performance impact (too rare) but it's gotta be done.
2744   // Since the code is rarely used, there is no penalty for moving it
2745   // out of line, and it can only improve I-cache density.
2746   // The decision to inline or out-of-line this final check is platform
2747   // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2748   Node* psc = gvn->transform(
2749     new PartialSubtypeCheckNode(*ctrl, subklass, superklass));
2750 
2751   IfNode *iff4 = gen_subtype_check_compare(*ctrl, psc, gvn->zerocon(T_OBJECT), BoolTest::ne, PROB_FAIR, gvn, T_ADDRESS);
2752   r_not_subtype->init_req(2, gvn->transform(new IfTrueNode (iff4)));
2753   r_ok_subtype ->init_req(3, gvn->transform(new IfFalseNode(iff4)));
2754 
2755   // Return false path; set default control to true path.
2756   *ctrl = gvn->transform(r_ok_subtype);
2757   return gvn->transform(r_not_subtype);
2758 }
2759 
2760 // Profile-driven exact type check:
2761 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2762                                     float prob,
2763                                     Node* *casted_receiver) {
2764   const TypeKlassPtr* tklass = TypeKlassPtr::make(klass);
2765   Node* recv_klass = load_object_klass(receiver);
2766   Node* want_klass = makecon(tklass);
2767   Node* cmp = _gvn.transform( new CmpPNode(recv_klass, want_klass) );
2768   Node* bol = _gvn.transform( new BoolNode(cmp, BoolTest::eq) );
2769   IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2770   set_control( _gvn.transform( new IfTrueNode (iff) ));
2771   Node* fail = _gvn.transform( new IfFalseNode(iff) );
2772 
2773   const TypeOopPtr* recv_xtype = tklass->as_instance_type();
2774   assert(recv_xtype->klass_is_exact(), "");
2775 
2776   // Subsume downstream occurrences of receiver with a cast to
2777   // recv_xtype, since now we know what the type will be.
2778   Node* cast = new CheckCastPPNode(control(), receiver, recv_xtype);
2779   (*casted_receiver) = _gvn.transform(cast);
2780   // (User must make the replace_in_map call.)
2781 
2782   return fail;
2783 }
2784 
2785 
2786 //------------------------------seems_never_null-------------------------------
2787 // Use null_seen information if it is available from the profile.
2788 // If we see an unexpected null at a type check we record it and force a
2789 // recompile; the offending check will be recompiled to handle NULLs.
2790 // If we see several offending BCIs, then all checks in the
2791 // method will be recompiled.
2792 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data, bool& speculating) {
2793   speculating = !_gvn.type(obj)->speculative_maybe_null();
2794   Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculating);
2795   if (UncommonNullCast               // Cutout for this technique
2796       && obj != null()               // And not the -Xcomp stupid case?
2797       && !too_many_traps(reason)
2798       ) {
2799     if (speculating) {
2800       return true;
2801     }
2802     if (data == NULL)
2803       // Edge case:  no mature data.  Be optimistic here.
2804       return true;
2805     // If the profile has not seen a null, assume it won't happen.
2806     assert(java_bc() == Bytecodes::_checkcast ||
2807            java_bc() == Bytecodes::_instanceof ||
2808            java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
2809     return !data->as_BitData()->null_seen();
2810   }
2811   speculating = false;
2812   return false;
2813 }
2814 
2815 //------------------------maybe_cast_profiled_receiver-------------------------
2816 // If the profile has seen exactly one type, narrow to exactly that type.
2817 // Subsequent type checks will always fold up.
2818 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
2819                                              ciKlass* require_klass,
2820                                              ciKlass* spec_klass,
2821                                              bool safe_for_replace) {
2822   if (!UseTypeProfile || !TypeProfileCasts) return NULL;
2823 
2824   Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != NULL);
2825 
2826   // Make sure we haven't already deoptimized from this tactic.
2827   if (too_many_traps_or_recompiles(reason))
2828     return NULL;
2829 
2830   // (No, this isn't a call, but it's enough like a virtual call
2831   // to use the same ciMethod accessor to get the profile info...)
2832   // If we have a speculative type use it instead of profiling (which
2833   // may not help us)
2834   ciKlass* exact_kls = spec_klass == NULL ? profile_has_unique_klass() : spec_klass;
2835   if (exact_kls != NULL) {// no cast failures here
2836     if (require_klass == NULL ||
2837         C->static_subtype_check(require_klass, exact_kls) == Compile::SSC_always_true) {
2838       // If we narrow the type to match what the type profile sees or
2839       // the speculative type, we can then remove the rest of the
2840       // cast.
2841       // This is a win, even if the exact_kls is very specific,
2842       // because downstream operations, such as method calls,
2843       // will often benefit from the sharper type.
2844       Node* exact_obj = not_null_obj; // will get updated in place...
2845       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
2846                                             &exact_obj);
2847       { PreserveJVMState pjvms(this);
2848         set_control(slow_ctl);
2849         uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile);
2850       }
2851       if (safe_for_replace) {
2852         replace_in_map(not_null_obj, exact_obj);
2853       }
2854       return exact_obj;
2855     }
2856     // assert(ssc == Compile::SSC_always_true)... except maybe the profile lied to us.
2857   }
2858 
2859   return NULL;
2860 }
2861 
2862 /**
2863  * Cast obj to type and emit guard unless we had too many traps here
2864  * already
2865  *
2866  * @param obj       node being casted
2867  * @param type      type to cast the node to
2868  * @param not_null  true if we know node cannot be null
2869  */
2870 Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
2871                                         ciKlass* type,
2872                                         bool not_null) {
2873   if (stopped()) {
2874     return obj;
2875   }
2876 
2877   // type == NULL if profiling tells us this object is always null
2878   if (type != NULL) {
2879     Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
2880     Deoptimization::DeoptReason null_reason = Deoptimization::Reason_speculate_null_check;
2881 
2882     if (!too_many_traps_or_recompiles(null_reason) &&
2883         !too_many_traps_or_recompiles(class_reason)) {
2884       Node* not_null_obj = NULL;
2885       // not_null is true if we know the object is not null and
2886       // there's no need for a null check
2887       if (!not_null) {
2888         Node* null_ctl = top();
2889         not_null_obj = null_check_oop(obj, &null_ctl, true, true, true);
2890         assert(null_ctl->is_top(), "no null control here");
2891       } else {
2892         not_null_obj = obj;
2893       }
2894 
2895       Node* exact_obj = not_null_obj;
2896       ciKlass* exact_kls = type;
2897       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
2898                                             &exact_obj);
2899       {
2900         PreserveJVMState pjvms(this);
2901         set_control(slow_ctl);
2902         uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile);
2903       }
2904       replace_in_map(not_null_obj, exact_obj);
2905       obj = exact_obj;
2906     }
2907   } else {
2908     if (!too_many_traps_or_recompiles(Deoptimization::Reason_null_assert)) {
2909       Node* exact_obj = null_assert(obj);
2910       replace_in_map(obj, exact_obj);
2911       obj = exact_obj;
2912     }
2913   }
2914   return obj;
2915 }
2916 
2917 //-------------------------------gen_instanceof--------------------------------
2918 // Generate an instance-of idiom.  Used by both the instance-of bytecode
2919 // and the reflective instance-of call.
2920 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
2921   kill_dead_locals();           // Benefit all the uncommon traps
2922   assert( !stopped(), "dead parse path should be checked in callers" );
2923   assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
2924          "must check for not-null not-dead klass in callers");
2925 
2926   // Make the merge point
2927   enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
2928   RegionNode* region = new RegionNode(PATH_LIMIT);
2929   Node*       phi    = new PhiNode(region, TypeInt::BOOL);
2930   C->set_has_split_ifs(true); // Has chance for split-if optimization
2931 
2932   ciProfileData* data = NULL;
2933   if (java_bc() == Bytecodes::_instanceof) {  // Only for the bytecode
2934     data = method()->method_data()->bci_to_data(bci());
2935   }
2936   bool speculative_not_null = false;
2937   bool never_see_null = (ProfileDynamicTypes  // aggressive use of profile
2938                          && seems_never_null(obj, data, speculative_not_null));
2939 
2940   // Null check; get casted pointer; set region slot 3
2941   Node* null_ctl = top();
2942   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
2943 
2944   // If not_null_obj is dead, only null-path is taken
2945   if (stopped()) {              // Doing instance-of on a NULL?
2946     set_control(null_ctl);
2947     return intcon(0);
2948   }
2949   region->init_req(_null_path, null_ctl);
2950   phi   ->init_req(_null_path, intcon(0)); // Set null path value
2951   if (null_ctl == top()) {
2952     // Do this eagerly, so that pattern matches like is_diamond_phi
2953     // will work even during parsing.
2954     assert(_null_path == PATH_LIMIT-1, "delete last");
2955     region->del_req(_null_path);
2956     phi   ->del_req(_null_path);
2957   }
2958 
2959   // Do we know the type check always succeed?
2960   bool known_statically = false;
2961   if (_gvn.type(superklass)->singleton()) {
2962     ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2963     ciKlass* subk = _gvn.type(obj)->is_oopptr()->klass();
2964     if (subk != NULL && subk->is_loaded()) {
2965       int static_res = C->static_subtype_check(superk, subk);
2966       known_statically = (static_res == Compile::SSC_always_true || static_res == Compile::SSC_always_false);
2967     }
2968   }
2969 
2970   if (!known_statically) {
2971     const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
2972     // We may not have profiling here or it may not help us. If we
2973     // have a speculative type use it to perform an exact cast.
2974     ciKlass* spec_obj_type = obj_type->speculative_type();
2975     if (spec_obj_type != NULL || (ProfileDynamicTypes && data != NULL)) {
2976       Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, NULL, spec_obj_type, safe_for_replace);
2977       if (stopped()) {            // Profile disagrees with this path.
2978         set_control(null_ctl);    // Null is the only remaining possibility.
2979         return intcon(0);
2980       }
2981       if (cast_obj != NULL) {
2982         not_null_obj = cast_obj;
2983       }
2984     }
2985   }
2986 
2987   // Load the object's klass
2988   Node* obj_klass = load_object_klass(not_null_obj);
2989 
2990   // Generate the subtype check
2991   Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass);
2992 
2993   // Plug in the success path to the general merge in slot 1.
2994   region->init_req(_obj_path, control());
2995   phi   ->init_req(_obj_path, intcon(1));
2996 
2997   // Plug in the failing path to the general merge in slot 2.
2998   region->init_req(_fail_path, not_subtype_ctrl);
2999   phi   ->init_req(_fail_path, intcon(0));
3000 
3001   // Return final merged results
3002   set_control( _gvn.transform(region) );
3003   record_for_igvn(region);
3004 
3005   // If we know the type check always succeeds then we don't use the
3006   // profiling data at this bytecode. Don't lose it, feed it to the
3007   // type system as a speculative type.
3008   if (safe_for_replace) {
3009     Node* casted_obj = record_profiled_receiver_for_speculation(obj);
3010     replace_in_map(obj, casted_obj);
3011   }
3012 
3013   return _gvn.transform(phi);
3014 }
3015 
3016 //-------------------------------gen_checkcast---------------------------------
3017 // Generate a checkcast idiom.  Used by both the checkcast bytecode and the
3018 // array store bytecode.  Stack must be as-if BEFORE doing the bytecode so the
3019 // uncommon-trap paths work.  Adjust stack after this call.
3020 // If failure_control is supplied and not null, it is filled in with
3021 // the control edge for the cast failure.  Otherwise, an appropriate
3022 // uncommon trap or exception is thrown.
3023 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
3024                               Node* *failure_control) {
3025   kill_dead_locals();           // Benefit all the uncommon traps
3026   const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr();
3027   const Type *toop = TypeOopPtr::make_from_klass(tk->klass());
3028 
3029   // Fast cutout:  Check the case that the cast is vacuously true.
3030   // This detects the common cases where the test will short-circuit
3031   // away completely.  We do this before we perform the null check,
3032   // because if the test is going to turn into zero code, we don't
3033   // want a residual null check left around.  (Causes a slowdown,
3034   // for example, in some objArray manipulations, such as a[i]=a[j].)
3035   if (tk->singleton()) {
3036     const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
3037     if (objtp != NULL && objtp->klass() != NULL) {
3038       switch (C->static_subtype_check(tk->klass(), objtp->klass())) {
3039       case Compile::SSC_always_true:
3040         // If we know the type check always succeed then we don't use
3041         // the profiling data at this bytecode. Don't lose it, feed it
3042         // to the type system as a speculative type.
3043         return record_profiled_receiver_for_speculation(obj);
3044       case Compile::SSC_always_false:
3045         // It needs a null check because a null will *pass* the cast check.
3046         // A non-null value will always produce an exception.
3047         return null_assert(obj);
3048       }
3049     }
3050   }
3051 
3052   ciProfileData* data = NULL;
3053   bool safe_for_replace = false;
3054   if (failure_control == NULL) {        // use MDO in regular case only
3055     assert(java_bc() == Bytecodes::_aastore ||
3056            java_bc() == Bytecodes::_checkcast,
3057            "interpreter profiles type checks only for these BCs");
3058     data = method()->method_data()->bci_to_data(bci());
3059     safe_for_replace = true;
3060   }
3061 
3062   // Make the merge point
3063   enum { _obj_path = 1, _null_path, PATH_LIMIT };
3064   RegionNode* region = new RegionNode(PATH_LIMIT);
3065   Node*       phi    = new PhiNode(region, toop);
3066   C->set_has_split_ifs(true); // Has chance for split-if optimization
3067 
3068   // Use null-cast information if it is available
3069   bool speculative_not_null = false;
3070   bool never_see_null = ((failure_control == NULL)  // regular case only
3071                          && seems_never_null(obj, data, speculative_not_null));
3072 
3073   // Null check; get casted pointer; set region slot 3
3074   Node* null_ctl = top();
3075   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3076 
3077   // If not_null_obj is dead, only null-path is taken
3078   if (stopped()) {              // Doing instance-of on a NULL?
3079     set_control(null_ctl);
3080     return null();
3081   }
3082   region->init_req(_null_path, null_ctl);
3083   phi   ->init_req(_null_path, null());  // Set null path value
3084   if (null_ctl == top()) {
3085     // Do this eagerly, so that pattern matches like is_diamond_phi
3086     // will work even during parsing.
3087     assert(_null_path == PATH_LIMIT-1, "delete last");
3088     region->del_req(_null_path);
3089     phi   ->del_req(_null_path);
3090   }
3091 
3092   Node* cast_obj = NULL;
3093   if (tk->klass_is_exact()) {
3094     // The following optimization tries to statically cast the speculative type of the object
3095     // (for example obtained during profiling) to the type of the superklass and then do a
3096     // dynamic check that the type of the object is what we expect. To work correctly
3097     // for checkcast and aastore the type of superklass should be exact.
3098     const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3099     // We may not have profiling here or it may not help us. If we have
3100     // a speculative type use it to perform an exact cast.
3101     ciKlass* spec_obj_type = obj_type->speculative_type();
3102     if (spec_obj_type != NULL || data != NULL) {
3103       cast_obj = maybe_cast_profiled_receiver(not_null_obj, tk->klass(), spec_obj_type, safe_for_replace);
3104       if (cast_obj != NULL) {
3105         if (failure_control != NULL) // failure is now impossible
3106           (*failure_control) = top();
3107         // adjust the type of the phi to the exact klass:
3108         phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3109       }
3110     }
3111   }
3112 
3113   if (cast_obj == NULL) {
3114     // Load the object's klass
3115     Node* obj_klass = load_object_klass(not_null_obj);
3116 
3117     // Generate the subtype check
3118     Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass );
3119 
3120     // Plug in success path into the merge
3121     cast_obj = _gvn.transform(new CheckCastPPNode(control(), not_null_obj, toop));
3122     // Failure path ends in uncommon trap (or may be dead - failure impossible)
3123     if (failure_control == NULL) {
3124       if (not_subtype_ctrl != top()) { // If failure is possible
3125         PreserveJVMState pjvms(this);
3126         set_control(not_subtype_ctrl);
3127         builtin_throw(Deoptimization::Reason_class_check, obj_klass);
3128       }
3129     } else {
3130       (*failure_control) = not_subtype_ctrl;
3131     }
3132   }
3133 
3134   region->init_req(_obj_path, control());
3135   phi   ->init_req(_obj_path, cast_obj);
3136 
3137   // A merge of NULL or Casted-NotNull obj
3138   Node* res = _gvn.transform(phi);
3139 
3140   // Note I do NOT always 'replace_in_map(obj,result)' here.
3141   //  if( tk->klass()->can_be_primary_super()  )
3142     // This means that if I successfully store an Object into an array-of-String
3143     // I 'forget' that the Object is really now known to be a String.  I have to
3144     // do this because we don't have true union types for interfaces - if I store
3145     // a Baz into an array-of-Interface and then tell the optimizer it's an
3146     // Interface, I forget that it's also a Baz and cannot do Baz-like field
3147     // references to it.  FIX THIS WHEN UNION TYPES APPEAR!
3148   //  replace_in_map( obj, res );
3149 
3150   // Return final merged results
3151   set_control( _gvn.transform(region) );
3152   record_for_igvn(region);
3153 
3154   return record_profiled_receiver_for_speculation(res);
3155 }
3156 
3157 //------------------------------next_monitor-----------------------------------
3158 // What number should be given to the next monitor?
3159 int GraphKit::next_monitor() {
3160   int current = jvms()->monitor_depth()* C->sync_stack_slots();
3161   int next = current + C->sync_stack_slots();
3162   // Keep the toplevel high water mark current:
3163   if (C->fixed_slots() < next)  C->set_fixed_slots(next);
3164   return current;
3165 }
3166 
3167 //------------------------------insert_mem_bar---------------------------------
3168 // Memory barrier to avoid floating things around
3169 // The membar serves as a pinch point between both control and all memory slices.
3170 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3171   MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3172   mb->init_req(TypeFunc::Control, control());
3173   mb->init_req(TypeFunc::Memory,  reset_memory());
3174   Node* membar = _gvn.transform(mb);
3175   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3176   set_all_memory_call(membar);
3177   return membar;
3178 }
3179 
3180 //-------------------------insert_mem_bar_volatile----------------------------
3181 // Memory barrier to avoid floating things around
3182 // The membar serves as a pinch point between both control and memory(alias_idx).
3183 // If you want to make a pinch point on all memory slices, do not use this
3184 // function (even with AliasIdxBot); use insert_mem_bar() instead.
3185 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3186   // When Parse::do_put_xxx updates a volatile field, it appends a series
3187   // of MemBarVolatile nodes, one for *each* volatile field alias category.
3188   // The first membar is on the same memory slice as the field store opcode.
3189   // This forces the membar to follow the store.  (Bug 6500685 broke this.)
3190   // All the other membars (for other volatile slices, including AliasIdxBot,
3191   // which stands for all unknown volatile slices) are control-dependent
3192   // on the first membar.  This prevents later volatile loads or stores
3193   // from sliding up past the just-emitted store.
3194 
3195   MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3196   mb->set_req(TypeFunc::Control,control());
3197   if (alias_idx == Compile::AliasIdxBot) {
3198     mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3199   } else {
3200     assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3201     mb->set_req(TypeFunc::Memory, memory(alias_idx));
3202   }
3203   Node* membar = _gvn.transform(mb);
3204   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3205   if (alias_idx == Compile::AliasIdxBot) {
3206     merged_memory()->set_base_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)));
3207   } else {
3208     set_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)),alias_idx);
3209   }
3210   return membar;
3211 }
3212 
3213 //------------------------------shared_lock------------------------------------
3214 // Emit locking code.
3215 FastLockNode* GraphKit::shared_lock(Node* obj) {
3216   // bci is either a monitorenter bc or InvocationEntryBci
3217   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3218   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3219 
3220   if( !GenerateSynchronizationCode )
3221     return NULL;                // Not locking things?
3222   if (stopped())                // Dead monitor?
3223     return NULL;
3224 
3225   assert(dead_locals_are_killed(), "should kill locals before sync. point");
3226 
3227   // Box the stack location
3228   Node* box = _gvn.transform(new BoxLockNode(next_monitor()));
3229   Node* mem = reset_memory();
3230 
3231   FastLockNode * flock = _gvn.transform(new FastLockNode(0, obj, box) )->as_FastLock();
3232   if (UseBiasedLocking && PrintPreciseBiasedLockingStatistics) {
3233     // Create the counters for this fast lock.
3234     flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3235   }
3236 
3237   // Create the rtm counters for this fast lock if needed.
3238   flock->create_rtm_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3239 
3240   // Add monitor to debug info for the slow path.  If we block inside the
3241   // slow path and de-opt, we need the monitor hanging around
3242   map()->push_monitor( flock );
3243 
3244   const TypeFunc *tf = LockNode::lock_type();
3245   LockNode *lock = new LockNode(C, tf);
3246 
3247   lock->init_req( TypeFunc::Control, control() );
3248   lock->init_req( TypeFunc::Memory , mem );
3249   lock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
3250   lock->init_req( TypeFunc::FramePtr, frameptr() );
3251   lock->init_req( TypeFunc::ReturnAdr, top() );
3252 
3253   lock->init_req(TypeFunc::Parms + 0, obj);
3254   lock->init_req(TypeFunc::Parms + 1, box);
3255   lock->init_req(TypeFunc::Parms + 2, flock);
3256   add_safepoint_edges(lock);
3257 
3258   lock = _gvn.transform( lock )->as_Lock();
3259 
3260   // lock has no side-effects, sets few values
3261   set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3262 
3263   insert_mem_bar(Op_MemBarAcquireLock);
3264 
3265   // Add this to the worklist so that the lock can be eliminated
3266   record_for_igvn(lock);
3267 
3268 #ifndef PRODUCT
3269   if (PrintLockStatistics) {
3270     // Update the counter for this lock.  Don't bother using an atomic
3271     // operation since we don't require absolute accuracy.
3272     lock->create_lock_counter(map()->jvms());
3273     increment_counter(lock->counter()->addr());
3274   }
3275 #endif
3276 
3277   return flock;
3278 }
3279 
3280 
3281 //------------------------------shared_unlock----------------------------------
3282 // Emit unlocking code.
3283 void GraphKit::shared_unlock(Node* box, Node* obj) {
3284   // bci is either a monitorenter bc or InvocationEntryBci
3285   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3286   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3287 
3288   if( !GenerateSynchronizationCode )
3289     return;
3290   if (stopped()) {               // Dead monitor?
3291     map()->pop_monitor();        // Kill monitor from debug info
3292     return;
3293   }
3294 
3295   // Memory barrier to avoid floating things down past the locked region
3296   insert_mem_bar(Op_MemBarReleaseLock);
3297 
3298   const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3299   UnlockNode *unlock = new UnlockNode(C, tf);
3300 #ifdef ASSERT
3301   unlock->set_dbg_jvms(sync_jvms());
3302 #endif
3303   uint raw_idx = Compile::AliasIdxRaw;
3304   unlock->init_req( TypeFunc::Control, control() );
3305   unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3306   unlock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
3307   unlock->init_req( TypeFunc::FramePtr, frameptr() );
3308   unlock->init_req( TypeFunc::ReturnAdr, top() );
3309 
3310   unlock->init_req(TypeFunc::Parms + 0, obj);
3311   unlock->init_req(TypeFunc::Parms + 1, box);
3312   unlock = _gvn.transform(unlock)->as_Unlock();
3313 
3314   Node* mem = reset_memory();
3315 
3316   // unlock has no side-effects, sets few values
3317   set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3318 
3319   // Kill monitor from debug info
3320   map()->pop_monitor( );
3321 }
3322 
3323 //-------------------------------get_layout_helper-----------------------------
3324 // If the given klass is a constant or known to be an array,
3325 // fetch the constant layout helper value into constant_value
3326 // and return (Node*)NULL.  Otherwise, load the non-constant
3327 // layout helper value, and return the node which represents it.
3328 // This two-faced routine is useful because allocation sites
3329 // almost always feature constant types.
3330 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3331   const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr();
3332   if (!StressReflectiveCode && inst_klass != NULL) {
3333     ciKlass* klass = inst_klass->klass();
3334     bool    xklass = inst_klass->klass_is_exact();
3335     if (xklass || klass->is_array_klass()) {
3336       jint lhelper = klass->layout_helper();
3337       if (lhelper != Klass::_lh_neutral_value) {
3338         constant_value = lhelper;
3339         return (Node*) NULL;
3340       }
3341     }
3342   }
3343   constant_value = Klass::_lh_neutral_value;  // put in a known value
3344   Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
3345   return make_load(NULL, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3346 }
3347 
3348 // We just put in an allocate/initialize with a big raw-memory effect.
3349 // Hook selected additional alias categories on the initialization.
3350 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3351                                 MergeMemNode* init_in_merge,
3352                                 Node* init_out_raw) {
3353   DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3354   assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3355 
3356   Node* prevmem = kit.memory(alias_idx);
3357   init_in_merge->set_memory_at(alias_idx, prevmem);
3358   kit.set_memory(init_out_raw, alias_idx);
3359 }
3360 
3361 //---------------------------set_output_for_allocation-------------------------
3362 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3363                                           const TypeOopPtr* oop_type,
3364                                           bool deoptimize_on_exception) {
3365   int rawidx = Compile::AliasIdxRaw;
3366   alloc->set_req( TypeFunc::FramePtr, frameptr() );
3367   add_safepoint_edges(alloc);
3368   Node* allocx = _gvn.transform(alloc);
3369   set_control( _gvn.transform(new ProjNode(allocx, TypeFunc::Control) ) );
3370   // create memory projection for i_o
3371   set_memory ( _gvn.transform( new ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3372   make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception);
3373 
3374   // create a memory projection as for the normal control path
3375   Node* malloc = _gvn.transform(new ProjNode(allocx, TypeFunc::Memory));
3376   set_memory(malloc, rawidx);
3377 
3378   // a normal slow-call doesn't change i_o, but an allocation does
3379   // we create a separate i_o projection for the normal control path
3380   set_i_o(_gvn.transform( new ProjNode(allocx, TypeFunc::I_O, false) ) );
3381   Node* rawoop = _gvn.transform( new ProjNode(allocx, TypeFunc::Parms) );
3382 
3383   // put in an initialization barrier
3384   InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3385                                                  rawoop)->as_Initialize();
3386   assert(alloc->initialization() == init,  "2-way macro link must work");
3387   assert(init ->allocation()     == alloc, "2-way macro link must work");
3388   {
3389     // Extract memory strands which may participate in the new object's
3390     // initialization, and source them from the new InitializeNode.
3391     // This will allow us to observe initializations when they occur,
3392     // and link them properly (as a group) to the InitializeNode.
3393     assert(init->in(InitializeNode::Memory) == malloc, "");
3394     MergeMemNode* minit_in = MergeMemNode::make(malloc);
3395     init->set_req(InitializeNode::Memory, minit_in);
3396     record_for_igvn(minit_in); // fold it up later, if possible
3397     Node* minit_out = memory(rawidx);
3398     assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3399     // Add an edge in the MergeMem for the header fields so an access
3400     // to one of those has correct memory state
3401     set_memory(minit_out, C->get_alias_index(oop_type->add_offset(oopDesc::mark_offset_in_bytes())));
3402     set_memory(minit_out, C->get_alias_index(oop_type->add_offset(oopDesc::klass_offset_in_bytes())));
3403     if (oop_type->isa_aryptr()) {
3404       const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3405       int            elemidx  = C->get_alias_index(telemref);
3406       hook_memory_on_init(*this, elemidx, minit_in, minit_out);
3407     } else if (oop_type->isa_instptr()) {
3408       ciInstanceKlass* ik = oop_type->klass()->as_instance_klass();
3409       for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3410         ciField* field = ik->nonstatic_field_at(i);
3411         if (field->offset() >= TrackedInitializationLimit * HeapWordSize)
3412           continue;  // do not bother to track really large numbers of fields
3413         // Find (or create) the alias category for this field:
3414         int fieldidx = C->alias_type(field)->index();
3415         hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3416       }
3417     }
3418   }
3419 
3420   // Cast raw oop to the real thing...
3421   Node* javaoop = new CheckCastPPNode(control(), rawoop, oop_type);
3422   javaoop = _gvn.transform(javaoop);
3423   C->set_recent_alloc(control(), javaoop);
3424   assert(just_allocated_object(control()) == javaoop, "just allocated");
3425 
3426 #ifdef ASSERT
3427   { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3428     assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc,
3429            "Ideal_allocation works");
3430     assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc,
3431            "Ideal_allocation works");
3432     if (alloc->is_AllocateArray()) {
3433       assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(),
3434              "Ideal_allocation works");
3435       assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(),
3436              "Ideal_allocation works");
3437     } else {
3438       assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3439     }
3440   }
3441 #endif //ASSERT
3442 
3443   return javaoop;
3444 }
3445 
3446 //---------------------------new_instance--------------------------------------
3447 // This routine takes a klass_node which may be constant (for a static type)
3448 // or may be non-constant (for reflective code).  It will work equally well
3449 // for either, and the graph will fold nicely if the optimizer later reduces
3450 // the type to a constant.
3451 // The optional arguments are for specialized use by intrinsics:
3452 //  - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3453 //  - If 'return_size_val', report the the total object size to the caller.
3454 //  - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3455 Node* GraphKit::new_instance(Node* klass_node,
3456                              Node* extra_slow_test,
3457                              Node* *return_size_val,
3458                              bool deoptimize_on_exception) {
3459   // Compute size in doublewords
3460   // The size is always an integral number of doublewords, represented
3461   // as a positive bytewise size stored in the klass's layout_helper.
3462   // The layout_helper also encodes (in a low bit) the need for a slow path.
3463   jint  layout_con = Klass::_lh_neutral_value;
3464   Node* layout_val = get_layout_helper(klass_node, layout_con);
3465   int   layout_is_con = (layout_val == NULL);
3466 
3467   if (extra_slow_test == NULL)  extra_slow_test = intcon(0);
3468   // Generate the initial go-slow test.  It's either ALWAYS (return a
3469   // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective
3470   // case) a computed value derived from the layout_helper.
3471   Node* initial_slow_test = NULL;
3472   if (layout_is_con) {
3473     assert(!StressReflectiveCode, "stress mode does not use these paths");
3474     bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3475     initial_slow_test = must_go_slow ? intcon(1) : extra_slow_test;
3476   } else {   // reflective case
3477     // This reflective path is used by Unsafe.allocateInstance.
3478     // (It may be stress-tested by specifying StressReflectiveCode.)
3479     // Basically, we want to get into the VM is there's an illegal argument.
3480     Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3481     initial_slow_test = _gvn.transform( new AndINode(layout_val, bit) );
3482     if (extra_slow_test != intcon(0)) {
3483       initial_slow_test = _gvn.transform( new OrINode(initial_slow_test, extra_slow_test) );
3484     }
3485     // (Macro-expander will further convert this to a Bool, if necessary.)
3486   }
3487 
3488   // Find the size in bytes.  This is easy; it's the layout_helper.
3489   // The size value must be valid even if the slow path is taken.
3490   Node* size = NULL;
3491   if (layout_is_con) {
3492     size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3493   } else {   // reflective case
3494     // This reflective path is used by clone and Unsafe.allocateInstance.
3495     size = ConvI2X(layout_val);
3496 
3497     // Clear the low bits to extract layout_helper_size_in_bytes:
3498     assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3499     Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3500     size = _gvn.transform( new AndXNode(size, mask) );
3501   }
3502   if (return_size_val != NULL) {
3503     (*return_size_val) = size;
3504   }
3505 
3506   // This is a precise notnull oop of the klass.
3507   // (Actually, it need not be precise if this is a reflective allocation.)
3508   // It's what we cast the result to.
3509   const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3510   if (!tklass)  tklass = TypeKlassPtr::OBJECT;
3511   const TypeOopPtr* oop_type = tklass->as_instance_type();
3512 
3513   // Now generate allocation code
3514 
3515   // The entire memory state is needed for slow path of the allocation
3516   // since GC and deoptimization can happened.
3517   Node *mem = reset_memory();
3518   set_all_memory(mem); // Create new memory state
3519 
3520   AllocateNode* alloc = new AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3521                                          control(), mem, i_o(),
3522                                          size, klass_node,
3523                                          initial_slow_test);
3524 
3525   return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception);
3526 }
3527 
3528 //-------------------------------new_array-------------------------------------
3529 // helper for both newarray and anewarray
3530 // The 'length' parameter is (obviously) the length of the array.
3531 // See comments on new_instance for the meaning of the other arguments.
3532 Node* GraphKit::new_array(Node* klass_node,     // array klass (maybe variable)
3533                           Node* length,         // number of array elements
3534                           int   nargs,          // number of arguments to push back for uncommon trap
3535                           Node* *return_size_val,
3536                           bool deoptimize_on_exception) {
3537   jint  layout_con = Klass::_lh_neutral_value;
3538   Node* layout_val = get_layout_helper(klass_node, layout_con);
3539   int   layout_is_con = (layout_val == NULL);
3540 
3541   if (!layout_is_con && !StressReflectiveCode &&
3542       !too_many_traps(Deoptimization::Reason_class_check)) {
3543     // This is a reflective array creation site.
3544     // Optimistically assume that it is a subtype of Object[],
3545     // so that we can fold up all the address arithmetic.
3546     layout_con = Klass::array_layout_helper(T_OBJECT);
3547     Node* cmp_lh = _gvn.transform( new CmpINode(layout_val, intcon(layout_con)) );
3548     Node* bol_lh = _gvn.transform( new BoolNode(cmp_lh, BoolTest::eq) );
3549     { BuildCutout unless(this, bol_lh, PROB_MAX);
3550       inc_sp(nargs);
3551       uncommon_trap(Deoptimization::Reason_class_check,
3552                     Deoptimization::Action_maybe_recompile);
3553     }
3554     layout_val = NULL;
3555     layout_is_con = true;
3556   }
3557 
3558   // Generate the initial go-slow test.  Make sure we do not overflow
3559   // if length is huge (near 2Gig) or negative!  We do not need
3560   // exact double-words here, just a close approximation of needed
3561   // double-words.  We can't add any offset or rounding bits, lest we
3562   // take a size -1 of bytes and make it positive.  Use an unsigned
3563   // compare, so negative sizes look hugely positive.
3564   int fast_size_limit = FastAllocateSizeLimit;
3565   if (layout_is_con) {
3566     assert(!StressReflectiveCode, "stress mode does not use these paths");
3567     // Increase the size limit if we have exact knowledge of array type.
3568     int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3569     fast_size_limit <<= (LogBytesPerLong - log2_esize);
3570   }
3571 
3572   Node* initial_slow_cmp  = _gvn.transform( new CmpUNode( length, intcon( fast_size_limit ) ) );
3573   Node* initial_slow_test = _gvn.transform( new BoolNode( initial_slow_cmp, BoolTest::gt ) );
3574 
3575   // --- Size Computation ---
3576   // array_size = round_to_heap(array_header + (length << elem_shift));
3577   // where round_to_heap(x) == align_to(x, MinObjAlignmentInBytes)
3578   // and align_to(x, y) == ((x + y-1) & ~(y-1))
3579   // The rounding mask is strength-reduced, if possible.
3580   int round_mask = MinObjAlignmentInBytes - 1;
3581   Node* header_size = NULL;
3582   int   header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3583   // (T_BYTE has the weakest alignment and size restrictions...)
3584   if (layout_is_con) {
3585     int       hsize  = Klass::layout_helper_header_size(layout_con);
3586     int       eshift = Klass::layout_helper_log2_element_size(layout_con);
3587     BasicType etype  = Klass::layout_helper_element_type(layout_con);
3588     if ((round_mask & ~right_n_bits(eshift)) == 0)
3589       round_mask = 0;  // strength-reduce it if it goes away completely
3590     assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3591     assert(header_size_min <= hsize, "generic minimum is smallest");
3592     header_size_min = hsize;
3593     header_size = intcon(hsize + round_mask);
3594   } else {
3595     Node* hss   = intcon(Klass::_lh_header_size_shift);
3596     Node* hsm   = intcon(Klass::_lh_header_size_mask);
3597     Node* hsize = _gvn.transform( new URShiftINode(layout_val, hss) );
3598     hsize       = _gvn.transform( new AndINode(hsize, hsm) );
3599     Node* mask  = intcon(round_mask);
3600     header_size = _gvn.transform( new AddINode(hsize, mask) );
3601   }
3602 
3603   Node* elem_shift = NULL;
3604   if (layout_is_con) {
3605     int eshift = Klass::layout_helper_log2_element_size(layout_con);
3606     if (eshift != 0)
3607       elem_shift = intcon(eshift);
3608   } else {
3609     // There is no need to mask or shift this value.
3610     // The semantics of LShiftINode include an implicit mask to 0x1F.
3611     assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3612     elem_shift = layout_val;
3613   }
3614 
3615   // Transition to native address size for all offset calculations:
3616   Node* lengthx = ConvI2X(length);
3617   Node* headerx = ConvI2X(header_size);
3618 #ifdef _LP64
3619   { const TypeInt* tilen = _gvn.find_int_type(length);
3620     if (tilen != NULL && tilen->_lo < 0) {
3621       // Add a manual constraint to a positive range.  Cf. array_element_address.
3622       jint size_max = fast_size_limit;
3623       if (size_max > tilen->_hi)  size_max = tilen->_hi;
3624       const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin);
3625 
3626       // Only do a narrow I2L conversion if the range check passed.
3627       IfNode* iff = new IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
3628       _gvn.transform(iff);
3629       RegionNode* region = new RegionNode(3);
3630       _gvn.set_type(region, Type::CONTROL);
3631       lengthx = new PhiNode(region, TypeLong::LONG);
3632       _gvn.set_type(lengthx, TypeLong::LONG);
3633 
3634       // Range check passed. Use ConvI2L node with narrow type.
3635       Node* passed = IfFalse(iff);
3636       region->init_req(1, passed);
3637       // Make I2L conversion control dependent to prevent it from
3638       // floating above the range check during loop optimizations.
3639       lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed));
3640 
3641       // Range check failed. Use ConvI2L with wide type because length may be invalid.
3642       region->init_req(2, IfTrue(iff));
3643       lengthx->init_req(2, ConvI2X(length));
3644 
3645       set_control(region);
3646       record_for_igvn(region);
3647       record_for_igvn(lengthx);
3648     }
3649   }
3650 #endif
3651 
3652   // Combine header size (plus rounding) and body size.  Then round down.
3653   // This computation cannot overflow, because it is used only in two
3654   // places, one where the length is sharply limited, and the other
3655   // after a successful allocation.
3656   Node* abody = lengthx;
3657   if (elem_shift != NULL)
3658     abody     = _gvn.transform( new LShiftXNode(lengthx, elem_shift) );
3659   Node* size  = _gvn.transform( new AddXNode(headerx, abody) );
3660   if (round_mask != 0) {
3661     Node* mask = MakeConX(~round_mask);
3662     size       = _gvn.transform( new AndXNode(size, mask) );
3663   }
3664   // else if round_mask == 0, the size computation is self-rounding
3665 
3666   if (return_size_val != NULL) {
3667     // This is the size
3668     (*return_size_val) = size;
3669   }
3670 
3671   // Now generate allocation code
3672 
3673   // The entire memory state is needed for slow path of the allocation
3674   // since GC and deoptimization can happened.
3675   Node *mem = reset_memory();
3676   set_all_memory(mem); // Create new memory state
3677 
3678   if (initial_slow_test->is_Bool()) {
3679     // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3680     initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3681   }
3682 
3683   // Create the AllocateArrayNode and its result projections
3684   AllocateArrayNode* alloc
3685     = new AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
3686                             control(), mem, i_o(),
3687                             size, klass_node,
3688                             initial_slow_test,
3689                             length);
3690 
3691   // Cast to correct type.  Note that the klass_node may be constant or not,
3692   // and in the latter case the actual array type will be inexact also.
3693   // (This happens via a non-constant argument to inline_native_newArray.)
3694   // In any case, the value of klass_node provides the desired array type.
3695   const TypeInt* length_type = _gvn.find_int_type(length);
3696   const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3697   if (ary_type->isa_aryptr() && length_type != NULL) {
3698     // Try to get a better type than POS for the size
3699     ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3700   }
3701 
3702   Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception);
3703 
3704   // Cast length on remaining path to be as narrow as possible
3705   if (map()->find_edge(length) >= 0) {
3706     Node* ccast = alloc->make_ideal_length(ary_type, &_gvn);
3707     if (ccast != length) {
3708       _gvn.set_type_bottom(ccast);
3709       record_for_igvn(ccast);
3710       replace_in_map(length, ccast);
3711     }
3712   }
3713 
3714   return javaoop;
3715 }
3716 
3717 // The following "Ideal_foo" functions are placed here because they recognize
3718 // the graph shapes created by the functions immediately above.
3719 
3720 //---------------------------Ideal_allocation----------------------------------
3721 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3722 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) {
3723   if (ptr == NULL) {     // reduce dumb test in callers
3724     return NULL;
3725   }
3726 
3727 #if INCLUDE_SHENANDOAHGC
3728   if (UseShenandoahGC) {
3729     BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
3730     ptr = bs->step_over_gc_barrier(ptr);
3731   }
3732 #endif
3733 
3734   if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
3735     ptr = ptr->in(1);
3736     if (ptr == NULL) return NULL;
3737   }
3738   // Return NULL for allocations with several casts:
3739   //   j.l.reflect.Array.newInstance(jobject, jint)
3740   //   Object.clone()
3741   // to keep more precise type from last cast.
3742   if (ptr->is_Proj()) {
3743     Node* allo = ptr->in(0);
3744     if (allo != NULL && allo->is_Allocate()) {
3745       return allo->as_Allocate();
3746     }
3747   }
3748   // Report failure to match.
3749   return NULL;
3750 }
3751 
3752 // Fancy version which also strips off an offset (and reports it to caller).
3753 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase,
3754                                              intptr_t& offset) {
3755   Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
3756   if (base == NULL)  return NULL;
3757   return Ideal_allocation(base, phase);
3758 }
3759 
3760 // Trace Initialize <- Proj[Parm] <- Allocate
3761 AllocateNode* InitializeNode::allocation() {
3762   Node* rawoop = in(InitializeNode::RawAddress);
3763   if (rawoop->is_Proj()) {
3764     Node* alloc = rawoop->in(0);
3765     if (alloc->is_Allocate()) {
3766       return alloc->as_Allocate();
3767     }
3768   }
3769   return NULL;
3770 }
3771 
3772 // Trace Allocate -> Proj[Parm] -> Initialize
3773 InitializeNode* AllocateNode::initialization() {
3774   ProjNode* rawoop = proj_out_or_null(AllocateNode::RawAddress);
3775   if (rawoop == NULL)  return NULL;
3776   for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3777     Node* init = rawoop->fast_out(i);
3778     if (init->is_Initialize()) {
3779       assert(init->as_Initialize()->allocation() == this, "2-way link");
3780       return init->as_Initialize();
3781     }
3782   }
3783   return NULL;
3784 }
3785 
3786 //----------------------------- loop predicates ---------------------------
3787 
3788 //------------------------------add_predicate_impl----------------------------
3789 void GraphKit::add_predicate_impl(Deoptimization::DeoptReason reason, int nargs) {
3790   // Too many traps seen?
3791   if (too_many_traps(reason)) {
3792 #ifdef ASSERT
3793     if (TraceLoopPredicate) {
3794       int tc = C->trap_count(reason);
3795       tty->print("too many traps=%s tcount=%d in ",
3796                     Deoptimization::trap_reason_name(reason), tc);
3797       method()->print(); // which method has too many predicate traps
3798       tty->cr();
3799     }
3800 #endif
3801     // We cannot afford to take more traps here,
3802     // do not generate predicate.
3803     return;
3804   }
3805 
3806   Node *cont    = _gvn.intcon(1);
3807   Node* opq     = _gvn.transform(new Opaque1Node(C, cont));
3808   Node *bol     = _gvn.transform(new Conv2BNode(opq));
3809   IfNode* iff   = create_and_map_if(control(), bol, PROB_MAX, COUNT_UNKNOWN);
3810   Node* iffalse = _gvn.transform(new IfFalseNode(iff));
3811   C->add_predicate_opaq(opq);
3812   {
3813     PreserveJVMState pjvms(this);
3814     set_control(iffalse);
3815     inc_sp(nargs);
3816     uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
3817   }
3818   Node* iftrue = _gvn.transform(new IfTrueNode(iff));
3819   set_control(iftrue);
3820 }
3821 
3822 //------------------------------add_predicate---------------------------------
3823 void GraphKit::add_predicate(int nargs) {
3824   if (UseLoopPredicate) {
3825     add_predicate_impl(Deoptimization::Reason_predicate, nargs);
3826   }
3827   if (UseProfiledLoopPredicate) {
3828     add_predicate_impl(Deoptimization::Reason_profile_predicate, nargs);
3829   }
3830   // loop's limit check predicate should be near the loop.
3831   add_predicate_impl(Deoptimization::Reason_loop_limit_check, nargs);
3832 }
3833 
3834 void GraphKit::sync_kit(IdealKit& ideal) {
3835   set_all_memory(ideal.merged_memory());
3836   set_i_o(ideal.i_o());
3837   set_control(ideal.ctrl());
3838 }
3839 
3840 void GraphKit::final_sync(IdealKit& ideal) {
3841   // Final sync IdealKit and graphKit.
3842   sync_kit(ideal);
3843 }
3844 
3845 Node* GraphKit::load_String_length(Node* ctrl, Node* str) {
3846   Node* len = load_array_length(load_String_value(ctrl, str));
3847   Node* coder = load_String_coder(ctrl, str);
3848   // Divide length by 2 if coder is UTF16
3849   return _gvn.transform(new RShiftINode(len, coder));
3850 }
3851 
3852 Node* GraphKit::load_String_value(Node* ctrl, Node* str) {
3853   int value_offset = java_lang_String::value_offset_in_bytes();
3854   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
3855                                                      false, NULL, 0);
3856   const TypePtr* value_field_type = string_type->add_offset(value_offset);
3857   const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
3858                                                   TypeAry::make(TypeInt::BYTE, TypeInt::POS),
3859                                                   ciTypeArrayKlass::make(T_BYTE), true, 0);
3860   Node* p = basic_plus_adr(str, str, value_offset);
3861   Node* load = access_load_at(str, p, value_field_type, value_type, T_OBJECT,
3862                               IN_HEAP | C2_CONTROL_DEPENDENT_LOAD);
3863   // String.value field is known to be @Stable.
3864   if (UseImplicitStableValues) {
3865     load = cast_array_to_stable(load, value_type);
3866   }
3867   return load;
3868 }
3869 
3870 Node* GraphKit::load_String_coder(Node* ctrl, Node* str) {
3871   if (!CompactStrings) {
3872     return intcon(java_lang_String::CODER_UTF16);
3873   }
3874   int coder_offset = java_lang_String::coder_offset_in_bytes();
3875   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
3876                                                      false, NULL, 0);
3877   const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
3878   int coder_field_idx = C->get_alias_index(coder_field_type);
3879   return make_load(ctrl, basic_plus_adr(str, str, coder_offset),
3880                    TypeInt::BYTE, T_BYTE, coder_field_idx, MemNode::unordered);
3881 }
3882 
3883 void GraphKit::store_String_value(Node* ctrl, Node* str, Node* value) {
3884   int value_offset = java_lang_String::value_offset_in_bytes();
3885   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
3886                                                      false, NULL, 0);
3887   const TypePtr* value_field_type = string_type->add_offset(value_offset);
3888   access_store_at(ctrl, str,  basic_plus_adr(str, value_offset), value_field_type,
3889                   value, TypeAryPtr::BYTES, T_OBJECT, IN_HEAP);
3890 }
3891 
3892 void GraphKit::store_String_coder(Node* ctrl, Node* str, Node* value) {
3893   int coder_offset = java_lang_String::coder_offset_in_bytes();
3894   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
3895                                                      false, NULL, 0);
3896   const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
3897   int coder_field_idx = C->get_alias_index(coder_field_type);
3898   store_to_memory(ctrl, basic_plus_adr(str, coder_offset),
3899                   value, T_BYTE, coder_field_idx, MemNode::unordered);
3900 }
3901 
3902 // Capture src and dst memory state with a MergeMemNode
3903 Node* GraphKit::capture_memory(const TypePtr* src_type, const TypePtr* dst_type) {
3904   if (src_type == dst_type) {
3905     // Types are equal, we don't need a MergeMemNode
3906     return memory(src_type);
3907   }
3908   MergeMemNode* merge = MergeMemNode::make(map()->memory());
3909   record_for_igvn(merge); // fold it up later, if possible
3910   int src_idx = C->get_alias_index(src_type);
3911   int dst_idx = C->get_alias_index(dst_type);
3912   merge->set_memory_at(src_idx, memory(src_idx));
3913   merge->set_memory_at(dst_idx, memory(dst_idx));
3914   return merge;
3915 }
3916 
3917 Node* GraphKit::compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count) {
3918   assert(Matcher::match_rule_supported(Op_StrCompressedCopy), "Intrinsic not supported");
3919   assert(src_type == TypeAryPtr::BYTES || src_type == TypeAryPtr::CHARS, "invalid source type");
3920   // If input and output memory types differ, capture both states to preserve
3921   // the dependency between preceding and subsequent loads/stores.
3922   // For example, the following program:
3923   //  StoreB
3924   //  compress_string
3925   //  LoadB
3926   // has this memory graph (use->def):
3927   //  LoadB -> compress_string -> CharMem
3928   //             ... -> StoreB -> ByteMem
3929   // The intrinsic hides the dependency between LoadB and StoreB, causing
3930   // the load to read from memory not containing the result of the StoreB.
3931   // The correct memory graph should look like this:
3932   //  LoadB -> compress_string -> MergeMem(CharMem, StoreB(ByteMem))
3933   Node* mem = capture_memory(src_type, TypeAryPtr::BYTES);
3934   StrCompressedCopyNode* str = new StrCompressedCopyNode(control(), mem, src, dst, count);
3935   Node* res_mem = _gvn.transform(new SCMemProjNode(str));
3936   set_memory(res_mem, TypeAryPtr::BYTES);
3937   return str;
3938 }
3939 
3940 void GraphKit::inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count) {
3941   assert(Matcher::match_rule_supported(Op_StrInflatedCopy), "Intrinsic not supported");
3942   assert(dst_type == TypeAryPtr::BYTES || dst_type == TypeAryPtr::CHARS, "invalid dest type");
3943   // Capture src and dst memory (see comment in 'compress_string').
3944   Node* mem = capture_memory(TypeAryPtr::BYTES, dst_type);
3945   StrInflatedCopyNode* str = new StrInflatedCopyNode(control(), mem, src, dst, count);
3946   set_memory(_gvn.transform(str), dst_type);
3947 }
3948 
3949 void GraphKit::inflate_string_slow(Node* src, Node* dst, Node* start, Node* count) {
3950   /**
3951    * int i_char = start;
3952    * for (int i_byte = 0; i_byte < count; i_byte++) {
3953    *   dst[i_char++] = (char)(src[i_byte] & 0xff);
3954    * }
3955    */
3956   add_predicate();
3957   RegionNode* head = new RegionNode(3);
3958   head->init_req(1, control());
3959   gvn().set_type(head, Type::CONTROL);
3960   record_for_igvn(head);
3961 
3962   Node* i_byte = new PhiNode(head, TypeInt::INT);
3963   i_byte->init_req(1, intcon(0));
3964   gvn().set_type(i_byte, TypeInt::INT);
3965   record_for_igvn(i_byte);
3966 
3967   Node* i_char = new PhiNode(head, TypeInt::INT);
3968   i_char->init_req(1, start);
3969   gvn().set_type(i_char, TypeInt::INT);
3970   record_for_igvn(i_char);
3971 
3972   Node* mem = PhiNode::make(head, memory(TypeAryPtr::BYTES), Type::MEMORY, TypeAryPtr::BYTES);
3973   gvn().set_type(mem, Type::MEMORY);
3974   record_for_igvn(mem);
3975   set_control(head);
3976   set_memory(mem, TypeAryPtr::BYTES);
3977   Node* ch = load_array_element(control(), src, i_byte, TypeAryPtr::BYTES);
3978   Node* st = store_to_memory(control(), array_element_address(dst, i_char, T_BYTE),
3979                              AndI(ch, intcon(0xff)), T_CHAR, TypeAryPtr::BYTES, MemNode::unordered,
3980                              false, false, true /* mismatched */);
3981 
3982   IfNode* iff = create_and_map_if(head, Bool(CmpI(i_byte, count), BoolTest::lt), PROB_FAIR, COUNT_UNKNOWN);
3983   head->init_req(2, IfTrue(iff));
3984   mem->init_req(2, st);
3985   i_byte->init_req(2, AddI(i_byte, intcon(1)));
3986   i_char->init_req(2, AddI(i_char, intcon(2)));
3987 
3988   set_control(IfFalse(iff));
3989   set_memory(st, TypeAryPtr::BYTES);
3990 }
3991 
3992 Node* GraphKit::make_constant_from_field(ciField* field, Node* obj) {
3993   if (!field->is_constant()) {
3994     return NULL; // Field not marked as constant.
3995   }
3996   ciInstance* holder = NULL;
3997   if (!field->is_static()) {
3998     ciObject* const_oop = obj->bottom_type()->is_oopptr()->const_oop();
3999     if (const_oop != NULL && const_oop->is_instance()) {
4000       holder = const_oop->as_instance();
4001     }
4002   }
4003   const Type* con_type = Type::make_constant_from_field(field, holder, field->layout_type(),
4004                                                         /*is_unsigned_load=*/false);
4005   if (con_type != NULL) {
4006     return makecon(con_type);
4007   }
4008   return NULL;
4009 }
4010 
4011 Node* GraphKit::cast_array_to_stable(Node* ary, const TypeAryPtr* ary_type) {
4012   // Reify the property as a CastPP node in Ideal graph to comply with monotonicity
4013   // assumption of CCP analysis.
4014   return _gvn.transform(new CastPPNode(ary, ary_type->cast_to_stable(true)));
4015 }