1 /*
   2  * Copyright (c) 2001, 2024, 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 "classfile/javaClasses.hpp"
  28 #include "ci/ciObjArray.hpp"
  29 #include "asm/register.hpp"
  30 #include "compiler/compileLog.hpp"
  31 #include "gc/shared/barrierSet.hpp"
  32 #include "gc/shared/c2/barrierSetC2.hpp"
  33 #include "interpreter/interpreter.hpp"
  34 #include "memory/resourceArea.hpp"
  35 #include "opto/addnode.hpp"
  36 #include "opto/castnode.hpp"
  37 #include "opto/convertnode.hpp"
  38 #include "opto/graphKit.hpp"
  39 #include "opto/idealKit.hpp"
  40 #include "opto/intrinsicnode.hpp"
  41 #include "opto/locknode.hpp"
  42 #include "opto/machnode.hpp"
  43 #include "opto/opaquenode.hpp"
  44 #include "opto/parse.hpp"
  45 #include "opto/rootnode.hpp"
  46 #include "opto/runtime.hpp"
  47 #include "opto/subtypenode.hpp"
  48 #include "runtime/deoptimization.hpp"
  49 #include "runtime/sharedRuntime.hpp"
  50 #include "utilities/bitMap.inline.hpp"
  51 #include "utilities/powerOfTwo.hpp"
  52 #include "utilities/growableArray.hpp"
  53 
  54 //----------------------------GraphKit-----------------------------------------
  55 // Main utility constructor.
  56 GraphKit::GraphKit(JVMState* jvms)
  57   : Phase(Phase::Parser),
  58     _env(C->env()),
  59     _gvn(*C->initial_gvn()),
  60     _barrier_set(BarrierSet::barrier_set()->barrier_set_c2())
  61 {
  62   _exceptions = jvms->map()->next_exception();
  63   if (_exceptions != nullptr)  jvms->map()->set_next_exception(nullptr);
  64   set_jvms(jvms);
  65 }
  66 
  67 // Private constructor for parser.
  68 GraphKit::GraphKit()
  69   : Phase(Phase::Parser),
  70     _env(C->env()),
  71     _gvn(*C->initial_gvn()),
  72     _barrier_set(BarrierSet::barrier_set()->barrier_set_c2())
  73 {
  74   _exceptions = nullptr;
  75   set_map(nullptr);
  76   debug_only(_sp = -99);
  77   debug_only(set_bci(-99));
  78 }
  79 
  80 
  81 
  82 //---------------------------clean_stack---------------------------------------
  83 // Clear away rubbish from the stack area of the JVM state.
  84 // This destroys any arguments that may be waiting on the stack.
  85 void GraphKit::clean_stack(int from_sp) {
  86   SafePointNode* map      = this->map();
  87   JVMState*      jvms     = this->jvms();
  88   int            stk_size = jvms->stk_size();
  89   int            stkoff   = jvms->stkoff();
  90   Node*          top      = this->top();
  91   for (int i = from_sp; i < stk_size; i++) {
  92     if (map->in(stkoff + i) != top) {
  93       map->set_req(stkoff + i, top);
  94     }
  95   }
  96 }
  97 
  98 
  99 //--------------------------------sync_jvms-----------------------------------
 100 // Make sure our current jvms agrees with our parse state.
 101 JVMState* GraphKit::sync_jvms() const {
 102   JVMState* jvms = this->jvms();
 103   jvms->set_bci(bci());       // Record the new bci in the JVMState
 104   jvms->set_sp(sp());         // Record the new sp in the JVMState
 105   assert(jvms_in_sync(), "jvms is now in sync");
 106   return jvms;
 107 }
 108 
 109 //--------------------------------sync_jvms_for_reexecute---------------------
 110 // Make sure our current jvms agrees with our parse state.  This version
 111 // uses the reexecute_sp for reexecuting bytecodes.
 112 JVMState* GraphKit::sync_jvms_for_reexecute() {
 113   JVMState* jvms = this->jvms();
 114   jvms->set_bci(bci());          // Record the new bci in the JVMState
 115   jvms->set_sp(reexecute_sp());  // Record the new sp in the JVMState
 116   return jvms;
 117 }
 118 
 119 #ifdef ASSERT
 120 bool GraphKit::jvms_in_sync() const {
 121   Parse* parse = is_Parse();
 122   if (parse == nullptr) {
 123     if (bci() !=      jvms()->bci())          return false;
 124     if (sp()  != (int)jvms()->sp())           return false;
 125     return true;
 126   }
 127   if (jvms()->method() != parse->method())    return false;
 128   if (jvms()->bci()    != parse->bci())       return false;
 129   int jvms_sp = jvms()->sp();
 130   if (jvms_sp          != parse->sp())        return false;
 131   int jvms_depth = jvms()->depth();
 132   if (jvms_depth       != parse->depth())     return false;
 133   return true;
 134 }
 135 
 136 // Local helper checks for special internal merge points
 137 // used to accumulate and merge exception states.
 138 // They are marked by the region's in(0) edge being the map itself.
 139 // Such merge points must never "escape" into the parser at large,
 140 // until they have been handed to gvn.transform.
 141 static bool is_hidden_merge(Node* reg) {
 142   if (reg == nullptr)  return false;
 143   if (reg->is_Phi()) {
 144     reg = reg->in(0);
 145     if (reg == nullptr)  return false;
 146   }
 147   return reg->is_Region() && reg->in(0) != nullptr && reg->in(0)->is_Root();
 148 }
 149 
 150 void GraphKit::verify_map() const {
 151   if (map() == nullptr)  return;  // null map is OK
 152   assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
 153   assert(!map()->has_exceptions(),    "call add_exception_states_from 1st");
 154   assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
 155 }
 156 
 157 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
 158   assert(ex_map->next_exception() == nullptr, "not already part of a chain");
 159   assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
 160 }
 161 #endif
 162 
 163 //---------------------------stop_and_kill_map---------------------------------
 164 // Set _map to null, signalling a stop to further bytecode execution.
 165 // First smash the current map's control to a constant, to mark it dead.
 166 void GraphKit::stop_and_kill_map() {
 167   SafePointNode* dead_map = stop();
 168   if (dead_map != nullptr) {
 169     dead_map->disconnect_inputs(C); // Mark the map as killed.
 170     assert(dead_map->is_killed(), "must be so marked");
 171   }
 172 }
 173 
 174 
 175 //--------------------------------stopped--------------------------------------
 176 // Tell if _map is null, or control is top.
 177 bool GraphKit::stopped() {
 178   if (map() == nullptr)        return true;
 179   else if (control() == top()) return true;
 180   else                         return false;
 181 }
 182 
 183 
 184 //-----------------------------has_exception_handler----------------------------------
 185 // Tell if this method or any caller method has exception handlers.
 186 bool GraphKit::has_exception_handler() {
 187   for (JVMState* jvmsp = jvms(); jvmsp != nullptr; jvmsp = jvmsp->caller()) {
 188     if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
 189       return true;
 190     }
 191   }
 192   return false;
 193 }
 194 
 195 //------------------------------save_ex_oop------------------------------------
 196 // Save an exception without blowing stack contents or other JVM state.
 197 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
 198   assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
 199   ex_map->add_req(ex_oop);
 200   debug_only(verify_exception_state(ex_map));
 201 }
 202 
 203 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
 204   assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
 205   Node* ex_oop = ex_map->in(ex_map->req()-1);
 206   if (clear_it)  ex_map->del_req(ex_map->req()-1);
 207   return ex_oop;
 208 }
 209 
 210 //-----------------------------saved_ex_oop------------------------------------
 211 // Recover a saved exception from its map.
 212 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
 213   return common_saved_ex_oop(ex_map, false);
 214 }
 215 
 216 //--------------------------clear_saved_ex_oop---------------------------------
 217 // Erase a previously saved exception from its map.
 218 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
 219   return common_saved_ex_oop(ex_map, true);
 220 }
 221 
 222 #ifdef ASSERT
 223 //---------------------------has_saved_ex_oop----------------------------------
 224 // Erase a previously saved exception from its map.
 225 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
 226   return ex_map->req() == ex_map->jvms()->endoff()+1;
 227 }
 228 #endif
 229 
 230 //-------------------------make_exception_state--------------------------------
 231 // Turn the current JVM state into an exception state, appending the ex_oop.
 232 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
 233   sync_jvms();
 234   SafePointNode* ex_map = stop();  // do not manipulate this map any more
 235   set_saved_ex_oop(ex_map, ex_oop);
 236   return ex_map;
 237 }
 238 
 239 
 240 //--------------------------add_exception_state--------------------------------
 241 // Add an exception to my list of exceptions.
 242 void GraphKit::add_exception_state(SafePointNode* ex_map) {
 243   if (ex_map == nullptr || ex_map->control() == top()) {
 244     return;
 245   }
 246 #ifdef ASSERT
 247   verify_exception_state(ex_map);
 248   if (has_exceptions()) {
 249     assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
 250   }
 251 #endif
 252 
 253   // If there is already an exception of exactly this type, merge with it.
 254   // In particular, null-checks and other low-level exceptions common up here.
 255   Node*       ex_oop  = saved_ex_oop(ex_map);
 256   const Type* ex_type = _gvn.type(ex_oop);
 257   if (ex_oop == top()) {
 258     // No action needed.
 259     return;
 260   }
 261   assert(ex_type->isa_instptr(), "exception must be an instance");
 262   for (SafePointNode* e2 = _exceptions; e2 != nullptr; e2 = e2->next_exception()) {
 263     const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
 264     // We check sp also because call bytecodes can generate exceptions
 265     // both before and after arguments are popped!
 266     if (ex_type2 == ex_type
 267         && e2->_jvms->sp() == ex_map->_jvms->sp()) {
 268       combine_exception_states(ex_map, e2);
 269       return;
 270     }
 271   }
 272 
 273   // No pre-existing exception of the same type.  Chain it on the list.
 274   push_exception_state(ex_map);
 275 }
 276 
 277 //-----------------------add_exception_states_from-----------------------------
 278 void GraphKit::add_exception_states_from(JVMState* jvms) {
 279   SafePointNode* ex_map = jvms->map()->next_exception();
 280   if (ex_map != nullptr) {
 281     jvms->map()->set_next_exception(nullptr);
 282     for (SafePointNode* next_map; ex_map != nullptr; ex_map = next_map) {
 283       next_map = ex_map->next_exception();
 284       ex_map->set_next_exception(nullptr);
 285       add_exception_state(ex_map);
 286     }
 287   }
 288 }
 289 
 290 //-----------------------transfer_exceptions_into_jvms-------------------------
 291 JVMState* GraphKit::transfer_exceptions_into_jvms() {
 292   if (map() == nullptr) {
 293     // We need a JVMS to carry the exceptions, but the map has gone away.
 294     // Create a scratch JVMS, cloned from any of the exception states...
 295     if (has_exceptions()) {
 296       _map = _exceptions;
 297       _map = clone_map();
 298       _map->set_next_exception(nullptr);
 299       clear_saved_ex_oop(_map);
 300       debug_only(verify_map());
 301     } else {
 302       // ...or created from scratch
 303       JVMState* jvms = new (C) JVMState(_method, nullptr);
 304       jvms->set_bci(_bci);
 305       jvms->set_sp(_sp);
 306       jvms->set_map(new SafePointNode(TypeFunc::Parms, jvms));
 307       set_jvms(jvms);
 308       for (uint i = 0; i < map()->req(); i++)  map()->init_req(i, top());
 309       set_all_memory(top());
 310       while (map()->req() < jvms->endoff())  map()->add_req(top());
 311     }
 312     // (This is a kludge, in case you didn't notice.)
 313     set_control(top());
 314   }
 315   JVMState* jvms = sync_jvms();
 316   assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
 317   jvms->map()->set_next_exception(_exceptions);
 318   _exceptions = nullptr;   // done with this set of exceptions
 319   return jvms;
 320 }
 321 
 322 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
 323   assert(is_hidden_merge(dstphi), "must be a special merge node");
 324   assert(is_hidden_merge(srcphi), "must be a special merge node");
 325   uint limit = srcphi->req();
 326   for (uint i = PhiNode::Input; i < limit; i++) {
 327     dstphi->add_req(srcphi->in(i));
 328   }
 329 }
 330 static inline void add_one_req(Node* dstphi, Node* src) {
 331   assert(is_hidden_merge(dstphi), "must be a special merge node");
 332   assert(!is_hidden_merge(src), "must not be a special merge node");
 333   dstphi->add_req(src);
 334 }
 335 
 336 //-----------------------combine_exception_states------------------------------
 337 // This helper function combines exception states by building phis on a
 338 // specially marked state-merging region.  These regions and phis are
 339 // untransformed, and can build up gradually.  The region is marked by
 340 // having a control input of its exception map, rather than null.  Such
 341 // regions do not appear except in this function, and in use_exception_state.
 342 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
 343   if (failing())  return;  // dying anyway...
 344   JVMState* ex_jvms = ex_map->_jvms;
 345   assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
 346   assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
 347   assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
 348   assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
 349   assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects");
 350   assert(ex_map->req() == phi_map->req(), "matching maps");
 351   uint tos = ex_jvms->stkoff() + ex_jvms->sp();
 352   Node*         hidden_merge_mark = root();
 353   Node*         region  = phi_map->control();
 354   MergeMemNode* phi_mem = phi_map->merged_memory();
 355   MergeMemNode* ex_mem  = ex_map->merged_memory();
 356   if (region->in(0) != hidden_merge_mark) {
 357     // The control input is not (yet) a specially-marked region in phi_map.
 358     // Make it so, and build some phis.
 359     region = new RegionNode(2);
 360     _gvn.set_type(region, Type::CONTROL);
 361     region->set_req(0, hidden_merge_mark);  // marks an internal ex-state
 362     region->init_req(1, phi_map->control());
 363     phi_map->set_control(region);
 364     Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
 365     record_for_igvn(io_phi);
 366     _gvn.set_type(io_phi, Type::ABIO);
 367     phi_map->set_i_o(io_phi);
 368     for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
 369       Node* m = mms.memory();
 370       Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
 371       record_for_igvn(m_phi);
 372       _gvn.set_type(m_phi, Type::MEMORY);
 373       mms.set_memory(m_phi);
 374     }
 375   }
 376 
 377   // Either or both of phi_map and ex_map might already be converted into phis.
 378   Node* ex_control = ex_map->control();
 379   // if there is special marking on ex_map also, we add multiple edges from src
 380   bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
 381   // how wide was the destination phi_map, originally?
 382   uint orig_width = region->req();
 383 
 384   if (add_multiple) {
 385     add_n_reqs(region, ex_control);
 386     add_n_reqs(phi_map->i_o(), ex_map->i_o());
 387   } else {
 388     // ex_map has no merges, so we just add single edges everywhere
 389     add_one_req(region, ex_control);
 390     add_one_req(phi_map->i_o(), ex_map->i_o());
 391   }
 392   for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
 393     if (mms.is_empty()) {
 394       // get a copy of the base memory, and patch some inputs into it
 395       const TypePtr* adr_type = mms.adr_type(C);
 396       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
 397       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
 398       mms.set_memory(phi);
 399       // Prepare to append interesting stuff onto the newly sliced phi:
 400       while (phi->req() > orig_width)  phi->del_req(phi->req()-1);
 401     }
 402     // Append stuff from ex_map:
 403     if (add_multiple) {
 404       add_n_reqs(mms.memory(), mms.memory2());
 405     } else {
 406       add_one_req(mms.memory(), mms.memory2());
 407     }
 408   }
 409   uint limit = ex_map->req();
 410   for (uint i = TypeFunc::Parms; i < limit; i++) {
 411     // Skip everything in the JVMS after tos.  (The ex_oop follows.)
 412     if (i == tos)  i = ex_jvms->monoff();
 413     Node* src = ex_map->in(i);
 414     Node* dst = phi_map->in(i);
 415     if (src != dst) {
 416       PhiNode* phi;
 417       if (dst->in(0) != region) {
 418         dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
 419         record_for_igvn(phi);
 420         _gvn.set_type(phi, phi->type());
 421         phi_map->set_req(i, dst);
 422         // Prepare to append interesting stuff onto the new phi:
 423         while (dst->req() > orig_width)  dst->del_req(dst->req()-1);
 424       } else {
 425         assert(dst->is_Phi(), "nobody else uses a hidden region");
 426         phi = dst->as_Phi();
 427       }
 428       if (add_multiple && src->in(0) == ex_control) {
 429         // Both are phis.
 430         add_n_reqs(dst, src);
 431       } else {
 432         while (dst->req() < region->req())  add_one_req(dst, src);
 433       }
 434       const Type* srctype = _gvn.type(src);
 435       if (phi->type() != srctype) {
 436         const Type* dsttype = phi->type()->meet_speculative(srctype);
 437         if (phi->type() != dsttype) {
 438           phi->set_type(dsttype);
 439           _gvn.set_type(phi, dsttype);
 440         }
 441       }
 442     }
 443   }
 444   phi_map->merge_replaced_nodes_with(ex_map);
 445 }
 446 
 447 //--------------------------use_exception_state--------------------------------
 448 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
 449   if (failing()) { stop(); return top(); }
 450   Node* region = phi_map->control();
 451   Node* hidden_merge_mark = root();
 452   assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
 453   Node* ex_oop = clear_saved_ex_oop(phi_map);
 454   if (region->in(0) == hidden_merge_mark) {
 455     // Special marking for internal ex-states.  Process the phis now.
 456     region->set_req(0, region);  // now it's an ordinary region
 457     set_jvms(phi_map->jvms());   // ...so now we can use it as a map
 458     // Note: Setting the jvms also sets the bci and sp.
 459     set_control(_gvn.transform(region));
 460     uint tos = jvms()->stkoff() + sp();
 461     for (uint i = 1; i < tos; i++) {
 462       Node* x = phi_map->in(i);
 463       if (x->in(0) == region) {
 464         assert(x->is_Phi(), "expected a special phi");
 465         phi_map->set_req(i, _gvn.transform(x));
 466       }
 467     }
 468     for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
 469       Node* x = mms.memory();
 470       if (x->in(0) == region) {
 471         assert(x->is_Phi(), "nobody else uses a hidden region");
 472         mms.set_memory(_gvn.transform(x));
 473       }
 474     }
 475     if (ex_oop->in(0) == region) {
 476       assert(ex_oop->is_Phi(), "expected a special phi");
 477       ex_oop = _gvn.transform(ex_oop);
 478     }
 479   } else {
 480     set_jvms(phi_map->jvms());
 481   }
 482 
 483   assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
 484   assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
 485   return ex_oop;
 486 }
 487 
 488 //---------------------------------java_bc-------------------------------------
 489 Bytecodes::Code GraphKit::java_bc() const {
 490   ciMethod* method = this->method();
 491   int       bci    = this->bci();
 492   if (method != nullptr && bci != InvocationEntryBci)
 493     return method->java_code_at_bci(bci);
 494   else
 495     return Bytecodes::_illegal;
 496 }
 497 
 498 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
 499                                                           bool must_throw) {
 500     // if the exception capability is set, then we will generate code
 501     // to check the JavaThread.should_post_on_exceptions flag to see
 502     // if we actually need to report exception events (for this
 503     // thread).  If we don't need to report exception events, we will
 504     // take the normal fast path provided by add_exception_events.  If
 505     // exception event reporting is enabled for this thread, we will
 506     // take the uncommon_trap in the BuildCutout below.
 507 
 508     // first must access the should_post_on_exceptions_flag in this thread's JavaThread
 509     Node* jthread = _gvn.transform(new ThreadLocalNode());
 510     Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
 511     Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw, MemNode::unordered);
 512 
 513     // Test the should_post_on_exceptions_flag vs. 0
 514     Node* chk = _gvn.transform( new CmpINode(should_post_flag, intcon(0)) );
 515     Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
 516 
 517     // Branch to slow_path if should_post_on_exceptions_flag was true
 518     { BuildCutout unless(this, tst, PROB_MAX);
 519       // Do not try anything fancy if we're notifying the VM on every throw.
 520       // Cf. case Bytecodes::_athrow in parse2.cpp.
 521       uncommon_trap(reason, Deoptimization::Action_none,
 522                     (ciKlass*)nullptr, (char*)nullptr, must_throw);
 523     }
 524 
 525 }
 526 
 527 //------------------------------builtin_throw----------------------------------
 528 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason) {
 529   bool must_throw = true;
 530 
 531   // If this particular condition has not yet happened at this
 532   // bytecode, then use the uncommon trap mechanism, and allow for
 533   // a future recompilation if several traps occur here.
 534   // If the throw is hot, try to use a more complicated inline mechanism
 535   // which keeps execution inside the compiled code.
 536   bool treat_throw_as_hot = false;
 537   ciMethodData* md = method()->method_data();
 538 
 539   if (ProfileTraps) {
 540     if (too_many_traps(reason)) {
 541       treat_throw_as_hot = true;
 542     }
 543     // (If there is no MDO at all, assume it is early in
 544     // execution, and that any deopts are part of the
 545     // startup transient, and don't need to be remembered.)
 546 
 547     // Also, if there is a local exception handler, treat all throws
 548     // as hot if there has been at least one in this method.
 549     if (C->trap_count(reason) != 0
 550         && method()->method_data()->trap_count(reason) != 0
 551         && has_exception_handler()) {
 552         treat_throw_as_hot = true;
 553     }
 554   }
 555 
 556   // If this throw happens frequently, an uncommon trap might cause
 557   // a performance pothole.  If there is a local exception handler,
 558   // and if this particular bytecode appears to be deoptimizing often,
 559   // let us handle the throw inline, with a preconstructed instance.
 560   // Note:   If the deopt count has blown up, the uncommon trap
 561   // runtime is going to flush this nmethod, not matter what.
 562   if (treat_throw_as_hot && method()->can_omit_stack_trace()) {
 563     // If the throw is local, we use a pre-existing instance and
 564     // punt on the backtrace.  This would lead to a missing backtrace
 565     // (a repeat of 4292742) if the backtrace object is ever asked
 566     // for its backtrace.
 567     // Fixing this remaining case of 4292742 requires some flavor of
 568     // escape analysis.  Leave that for the future.
 569     ciInstance* ex_obj = nullptr;
 570     switch (reason) {
 571     case Deoptimization::Reason_null_check:
 572       ex_obj = env()->NullPointerException_instance();
 573       break;
 574     case Deoptimization::Reason_div0_check:
 575       ex_obj = env()->ArithmeticException_instance();
 576       break;
 577     case Deoptimization::Reason_range_check:
 578       ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
 579       break;
 580     case Deoptimization::Reason_class_check:
 581       ex_obj = env()->ClassCastException_instance();
 582       break;
 583     case Deoptimization::Reason_array_check:
 584       ex_obj = env()->ArrayStoreException_instance();
 585       break;
 586     default:
 587       break;
 588     }
 589     if (failing()) { stop(); return; }  // exception allocation might fail
 590     if (ex_obj != nullptr) {
 591       if (env()->jvmti_can_post_on_exceptions()) {
 592         // check if we must post exception events, take uncommon trap if so
 593         uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
 594         // here if should_post_on_exceptions is false
 595         // continue on with the normal codegen
 596       }
 597 
 598       // Cheat with a preallocated exception object.
 599       if (C->log() != nullptr)
 600         C->log()->elem("hot_throw preallocated='1' reason='%s'",
 601                        Deoptimization::trap_reason_name(reason));
 602       const TypeInstPtr* ex_con  = TypeInstPtr::make(ex_obj);
 603       Node*              ex_node = _gvn.transform(ConNode::make(ex_con));
 604 
 605       // Clear the detail message of the preallocated exception object.
 606       // Weblogic sometimes mutates the detail message of exceptions
 607       // using reflection.
 608       int offset = java_lang_Throwable::get_detailMessage_offset();
 609       const TypePtr* adr_typ = ex_con->add_offset(offset);
 610 
 611       Node *adr = basic_plus_adr(ex_node, ex_node, offset);
 612       const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
 613       Node *store = access_store_at(ex_node, adr, adr_typ, null(), val_type, T_OBJECT, IN_HEAP);
 614 
 615       if (!method()->has_exception_handlers()) {
 616         // We don't need to preserve the stack if there's no handler as the entire frame is going to be popped anyway.
 617         // This prevents issues with exception handling and late inlining.
 618         set_sp(0);
 619         clean_stack(0);
 620       }
 621 
 622       add_exception_state(make_exception_state(ex_node));
 623       return;
 624     }
 625   }
 626 
 627   // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
 628   // It won't be much cheaper than bailing to the interp., since we'll
 629   // have to pass up all the debug-info, and the runtime will have to
 630   // create the stack trace.
 631 
 632   // Usual case:  Bail to interpreter.
 633   // Reserve the right to recompile if we haven't seen anything yet.
 634 
 635   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? C->method() : nullptr;
 636   Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
 637   if (treat_throw_as_hot
 638       && (method()->method_data()->trap_recompiled_at(bci(), m)
 639           || C->too_many_traps(reason))) {
 640     // We cannot afford to take more traps here.  Suffer in the interpreter.
 641     if (C->log() != nullptr)
 642       C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
 643                      Deoptimization::trap_reason_name(reason),
 644                      C->trap_count(reason));
 645     action = Deoptimization::Action_none;
 646   }
 647 
 648   // "must_throw" prunes the JVM state to include only the stack, if there
 649   // are no local exception handlers.  This should cut down on register
 650   // allocation time and code size, by drastically reducing the number
 651   // of in-edges on the call to the uncommon trap.
 652 
 653   uncommon_trap(reason, action, (ciKlass*)nullptr, (char*)nullptr, must_throw);
 654 }
 655 
 656 
 657 //----------------------------PreserveJVMState---------------------------------
 658 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
 659   debug_only(kit->verify_map());
 660   _kit    = kit;
 661   _map    = kit->map();   // preserve the map
 662   _sp     = kit->sp();
 663   kit->set_map(clone_map ? kit->clone_map() : nullptr);
 664 #ifdef ASSERT
 665   _bci    = kit->bci();
 666   Parse* parser = kit->is_Parse();
 667   int block = (parser == nullptr || parser->block() == nullptr) ? -1 : parser->block()->rpo();
 668   _block  = block;
 669 #endif
 670 }
 671 PreserveJVMState::~PreserveJVMState() {
 672   GraphKit* kit = _kit;
 673 #ifdef ASSERT
 674   assert(kit->bci() == _bci, "bci must not shift");
 675   Parse* parser = kit->is_Parse();
 676   int block = (parser == nullptr || parser->block() == nullptr) ? -1 : parser->block()->rpo();
 677   assert(block == _block,    "block must not shift");
 678 #endif
 679   kit->set_map(_map);
 680   kit->set_sp(_sp);
 681 }
 682 
 683 
 684 //-----------------------------BuildCutout-------------------------------------
 685 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
 686   : PreserveJVMState(kit)
 687 {
 688   assert(p->is_Con() || p->is_Bool(), "test must be a bool");
 689   SafePointNode* outer_map = _map;   // preserved map is caller's
 690   SafePointNode* inner_map = kit->map();
 691   IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
 692   outer_map->set_control(kit->gvn().transform( new IfTrueNode(iff) ));
 693   inner_map->set_control(kit->gvn().transform( new IfFalseNode(iff) ));
 694 }
 695 BuildCutout::~BuildCutout() {
 696   GraphKit* kit = _kit;
 697   assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
 698 }
 699 
 700 //---------------------------PreserveReexecuteState----------------------------
 701 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
 702   assert(!kit->stopped(), "must call stopped() before");
 703   _kit    =    kit;
 704   _sp     =    kit->sp();
 705   _reexecute = kit->jvms()->_reexecute;
 706 }
 707 PreserveReexecuteState::~PreserveReexecuteState() {
 708   if (_kit->stopped()) return;
 709   _kit->jvms()->_reexecute = _reexecute;
 710   _kit->set_sp(_sp);
 711 }
 712 
 713 //------------------------------clone_map--------------------------------------
 714 // Implementation of PreserveJVMState
 715 //
 716 // Only clone_map(...) here. If this function is only used in the
 717 // PreserveJVMState class we may want to get rid of this extra
 718 // function eventually and do it all there.
 719 
 720 SafePointNode* GraphKit::clone_map() {
 721   if (map() == nullptr)  return nullptr;
 722 
 723   // Clone the memory edge first
 724   Node* mem = MergeMemNode::make(map()->memory());
 725   gvn().set_type_bottom(mem);
 726 
 727   SafePointNode *clonemap = (SafePointNode*)map()->clone();
 728   JVMState* jvms = this->jvms();
 729   JVMState* clonejvms = jvms->clone_shallow(C);
 730   clonemap->set_memory(mem);
 731   clonemap->set_jvms(clonejvms);
 732   clonejvms->set_map(clonemap);
 733   record_for_igvn(clonemap);
 734   gvn().set_type_bottom(clonemap);
 735   return clonemap;
 736 }
 737 
 738 //-----------------------------destruct_map_clone------------------------------
 739 //
 740 // Order of destruct is important to increase the likelyhood that memory can be re-used. We need
 741 // to destruct/free/delete in the exact opposite order as clone_map().
 742 void GraphKit::destruct_map_clone(SafePointNode* sfp) {
 743   if (sfp == nullptr) return;
 744 
 745   Node* mem = sfp->memory();
 746   JVMState* jvms = sfp->jvms();
 747 
 748   if (jvms != nullptr) {
 749     delete jvms;
 750   }
 751 
 752   remove_for_igvn(sfp);
 753   gvn().clear_type(sfp);
 754   sfp->destruct(&_gvn);
 755 
 756   if (mem != nullptr) {
 757     gvn().clear_type(mem);
 758     mem->destruct(&_gvn);
 759   }
 760 }
 761 
 762 //-----------------------------set_map_clone-----------------------------------
 763 void GraphKit::set_map_clone(SafePointNode* m) {
 764   _map = m;
 765   _map = clone_map();
 766   _map->set_next_exception(nullptr);
 767   debug_only(verify_map());
 768 }
 769 
 770 
 771 //----------------------------kill_dead_locals---------------------------------
 772 // Detect any locals which are known to be dead, and force them to top.
 773 void GraphKit::kill_dead_locals() {
 774   // Consult the liveness information for the locals.  If any
 775   // of them are unused, then they can be replaced by top().  This
 776   // should help register allocation time and cut down on the size
 777   // of the deoptimization information.
 778 
 779   // This call is made from many of the bytecode handling
 780   // subroutines called from the Big Switch in do_one_bytecode.
 781   // Every bytecode which might include a slow path is responsible
 782   // for killing its dead locals.  The more consistent we
 783   // are about killing deads, the fewer useless phis will be
 784   // constructed for them at various merge points.
 785 
 786   // bci can be -1 (InvocationEntryBci).  We return the entry
 787   // liveness for the method.
 788 
 789   if (method() == nullptr || method()->code_size() == 0) {
 790     // We are building a graph for a call to a native method.
 791     // All locals are live.
 792     return;
 793   }
 794 
 795   ResourceMark rm;
 796 
 797   // Consult the liveness information for the locals.  If any
 798   // of them are unused, then they can be replaced by top().  This
 799   // should help register allocation time and cut down on the size
 800   // of the deoptimization information.
 801   MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
 802 
 803   int len = (int)live_locals.size();
 804   assert(len <= jvms()->loc_size(), "too many live locals");
 805   for (int local = 0; local < len; local++) {
 806     if (!live_locals.at(local)) {
 807       set_local(local, top());
 808     }
 809   }
 810 }
 811 
 812 #ifdef ASSERT
 813 //-------------------------dead_locals_are_killed------------------------------
 814 // Return true if all dead locals are set to top in the map.
 815 // Used to assert "clean" debug info at various points.
 816 bool GraphKit::dead_locals_are_killed() {
 817   if (method() == nullptr || method()->code_size() == 0) {
 818     // No locals need to be dead, so all is as it should be.
 819     return true;
 820   }
 821 
 822   // Make sure somebody called kill_dead_locals upstream.
 823   ResourceMark rm;
 824   for (JVMState* jvms = this->jvms(); jvms != nullptr; jvms = jvms->caller()) {
 825     if (jvms->loc_size() == 0)  continue;  // no locals to consult
 826     SafePointNode* map = jvms->map();
 827     ciMethod* method = jvms->method();
 828     int       bci    = jvms->bci();
 829     if (jvms == this->jvms()) {
 830       bci = this->bci();  // it might not yet be synched
 831     }
 832     MethodLivenessResult live_locals = method->liveness_at_bci(bci);
 833     int len = (int)live_locals.size();
 834     if (!live_locals.is_valid() || len == 0)
 835       // This method is trivial, or is poisoned by a breakpoint.
 836       return true;
 837     assert(len == jvms->loc_size(), "live map consistent with locals map");
 838     for (int local = 0; local < len; local++) {
 839       if (!live_locals.at(local) && map->local(jvms, local) != top()) {
 840         if (PrintMiscellaneous && (Verbose || WizardMode)) {
 841           tty->print_cr("Zombie local %d: ", local);
 842           jvms->dump();
 843         }
 844         return false;
 845       }
 846     }
 847   }
 848   return true;
 849 }
 850 
 851 #endif //ASSERT
 852 
 853 // Helper function for enforcing certain bytecodes to reexecute if deoptimization happens.
 854 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
 855   ciMethod* cur_method = jvms->method();
 856   int       cur_bci   = jvms->bci();
 857   if (cur_method != nullptr && cur_bci != InvocationEntryBci) {
 858     Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
 859     return Interpreter::bytecode_should_reexecute(code) ||
 860            (is_anewarray && code == Bytecodes::_multianewarray);
 861     // Reexecute _multianewarray bytecode which was replaced with
 862     // sequence of [a]newarray. See Parse::do_multianewarray().
 863     //
 864     // Note: interpreter should not have it set since this optimization
 865     // is limited by dimensions and guarded by flag so in some cases
 866     // multianewarray() runtime calls will be generated and
 867     // the bytecode should not be reexecutes (stack will not be reset).
 868   } else {
 869     return false;
 870   }
 871 }
 872 
 873 // Helper function for adding JVMState and debug information to node
 874 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
 875   // Add the safepoint edges to the call (or other safepoint).
 876 
 877   // Make sure dead locals are set to top.  This
 878   // should help register allocation time and cut down on the size
 879   // of the deoptimization information.
 880   assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
 881 
 882   // Walk the inline list to fill in the correct set of JVMState's
 883   // Also fill in the associated edges for each JVMState.
 884 
 885   // If the bytecode needs to be reexecuted we need to put
 886   // the arguments back on the stack.
 887   const bool should_reexecute = jvms()->should_reexecute();
 888   JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
 889 
 890   // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
 891   // undefined if the bci is different.  This is normal for Parse but it
 892   // should not happen for LibraryCallKit because only one bci is processed.
 893   assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
 894          "in LibraryCallKit the reexecute bit should not change");
 895 
 896   // If we are guaranteed to throw, we can prune everything but the
 897   // input to the current bytecode.
 898   bool can_prune_locals = false;
 899   uint stack_slots_not_pruned = 0;
 900   int inputs = 0, depth = 0;
 901   if (must_throw) {
 902     assert(method() == youngest_jvms->method(), "sanity");
 903     if (compute_stack_effects(inputs, depth)) {
 904       can_prune_locals = true;
 905       stack_slots_not_pruned = inputs;
 906     }
 907   }
 908 
 909   if (env()->should_retain_local_variables()) {
 910     // At any safepoint, this method can get breakpointed, which would
 911     // then require an immediate deoptimization.
 912     can_prune_locals = false;  // do not prune locals
 913     stack_slots_not_pruned = 0;
 914   }
 915 
 916   // do not scribble on the input jvms
 917   JVMState* out_jvms = youngest_jvms->clone_deep(C);
 918   call->set_jvms(out_jvms); // Start jvms list for call node
 919 
 920   // For a known set of bytecodes, the interpreter should reexecute them if
 921   // deoptimization happens. We set the reexecute state for them here
 922   if (out_jvms->is_reexecute_undefined() && //don't change if already specified
 923       should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
 924 #ifdef ASSERT
 925     int inputs = 0, not_used; // initialized by GraphKit::compute_stack_effects()
 926     assert(method() == youngest_jvms->method(), "sanity");
 927     assert(compute_stack_effects(inputs, not_used), "unknown bytecode: %s", Bytecodes::name(java_bc()));
 928     assert(out_jvms->sp() >= (uint)inputs, "not enough operands for reexecution");
 929 #endif // ASSERT
 930     out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
 931   }
 932 
 933   // Presize the call:
 934   DEBUG_ONLY(uint non_debug_edges = call->req());
 935   call->add_req_batch(top(), youngest_jvms->debug_depth());
 936   assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
 937 
 938   // Set up edges so that the call looks like this:
 939   //  Call [state:] ctl io mem fptr retadr
 940   //       [parms:] parm0 ... parmN
 941   //       [root:]  loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 942   //    [...mid:]   loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
 943   //       [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 944   // Note that caller debug info precedes callee debug info.
 945 
 946   // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
 947   uint debug_ptr = call->req();
 948 
 949   // Loop over the map input edges associated with jvms, add them
 950   // to the call node, & reset all offsets to match call node array.
 951   for (JVMState* in_jvms = youngest_jvms; in_jvms != nullptr; ) {
 952     uint debug_end   = debug_ptr;
 953     uint debug_start = debug_ptr - in_jvms->debug_size();
 954     debug_ptr = debug_start;  // back up the ptr
 955 
 956     uint p = debug_start;  // walks forward in [debug_start, debug_end)
 957     uint j, k, l;
 958     SafePointNode* in_map = in_jvms->map();
 959     out_jvms->set_map(call);
 960 
 961     if (can_prune_locals) {
 962       assert(in_jvms->method() == out_jvms->method(), "sanity");
 963       // If the current throw can reach an exception handler in this JVMS,
 964       // then we must keep everything live that can reach that handler.
 965       // As a quick and dirty approximation, we look for any handlers at all.
 966       if (in_jvms->method()->has_exception_handlers()) {
 967         can_prune_locals = false;
 968       }
 969     }
 970 
 971     // Add the Locals
 972     k = in_jvms->locoff();
 973     l = in_jvms->loc_size();
 974     out_jvms->set_locoff(p);
 975     if (!can_prune_locals) {
 976       for (j = 0; j < l; j++)
 977         call->set_req(p++, in_map->in(k+j));
 978     } else {
 979       p += l;  // already set to top above by add_req_batch
 980     }
 981 
 982     // Add the Expression Stack
 983     k = in_jvms->stkoff();
 984     l = in_jvms->sp();
 985     out_jvms->set_stkoff(p);
 986     if (!can_prune_locals) {
 987       for (j = 0; j < l; j++)
 988         call->set_req(p++, in_map->in(k+j));
 989     } else if (can_prune_locals && stack_slots_not_pruned != 0) {
 990       // Divide stack into {S0,...,S1}, where S0 is set to top.
 991       uint s1 = stack_slots_not_pruned;
 992       stack_slots_not_pruned = 0;  // for next iteration
 993       if (s1 > l)  s1 = l;
 994       uint s0 = l - s1;
 995       p += s0;  // skip the tops preinstalled by add_req_batch
 996       for (j = s0; j < l; j++)
 997         call->set_req(p++, in_map->in(k+j));
 998     } else {
 999       p += l;  // already set to top above by add_req_batch
1000     }
1001 
1002     // Add the Monitors
1003     k = in_jvms->monoff();
1004     l = in_jvms->mon_size();
1005     out_jvms->set_monoff(p);
1006     for (j = 0; j < l; j++)
1007       call->set_req(p++, in_map->in(k+j));
1008 
1009     // Copy any scalar object fields.
1010     k = in_jvms->scloff();
1011     l = in_jvms->scl_size();
1012     out_jvms->set_scloff(p);
1013     for (j = 0; j < l; j++)
1014       call->set_req(p++, in_map->in(k+j));
1015 
1016     // Finish the new jvms.
1017     out_jvms->set_endoff(p);
1018 
1019     assert(out_jvms->endoff()     == debug_end,             "fill ptr must match");
1020     assert(out_jvms->depth()      == in_jvms->depth(),      "depth must match");
1021     assert(out_jvms->loc_size()   == in_jvms->loc_size(),   "size must match");
1022     assert(out_jvms->mon_size()   == in_jvms->mon_size(),   "size must match");
1023     assert(out_jvms->scl_size()   == in_jvms->scl_size(),   "size must match");
1024     assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
1025 
1026     // Update the two tail pointers in parallel.
1027     out_jvms = out_jvms->caller();
1028     in_jvms  = in_jvms->caller();
1029   }
1030 
1031   assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
1032 
1033   // Test the correctness of JVMState::debug_xxx accessors:
1034   assert(call->jvms()->debug_start() == non_debug_edges, "");
1035   assert(call->jvms()->debug_end()   == call->req(), "");
1036   assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
1037 }
1038 
1039 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
1040   Bytecodes::Code code = java_bc();
1041   if (code == Bytecodes::_wide) {
1042     code = method()->java_code_at_bci(bci() + 1);
1043   }
1044 
1045   if (code != Bytecodes::_illegal) {
1046     depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1047   }
1048 
1049   auto rsize = [&]() {
1050     assert(code != Bytecodes::_illegal, "code is illegal!");
1051     BasicType rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1052     return (rtype < T_CONFLICT) ? type2size[rtype] : 0;
1053   };
1054 
1055   switch (code) {
1056   case Bytecodes::_illegal:
1057     return false;
1058 
1059   case Bytecodes::_ldc:
1060   case Bytecodes::_ldc_w:
1061   case Bytecodes::_ldc2_w:
1062     inputs = 0;
1063     break;
1064 
1065   case Bytecodes::_dup:         inputs = 1;  break;
1066   case Bytecodes::_dup_x1:      inputs = 2;  break;
1067   case Bytecodes::_dup_x2:      inputs = 3;  break;
1068   case Bytecodes::_dup2:        inputs = 2;  break;
1069   case Bytecodes::_dup2_x1:     inputs = 3;  break;
1070   case Bytecodes::_dup2_x2:     inputs = 4;  break;
1071   case Bytecodes::_swap:        inputs = 2;  break;
1072   case Bytecodes::_arraylength: inputs = 1;  break;
1073 
1074   case Bytecodes::_getstatic:
1075   case Bytecodes::_putstatic:
1076   case Bytecodes::_getfield:
1077   case Bytecodes::_putfield:
1078     {
1079       bool ignored_will_link;
1080       ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1081       int      size  = field->type()->size();
1082       bool is_get = (depth >= 0), is_static = (depth & 1);
1083       inputs = (is_static ? 0 : 1);
1084       if (is_get) {
1085         depth = size - inputs;
1086       } else {
1087         inputs += size;        // putxxx pops the value from the stack
1088         depth = - inputs;
1089       }
1090     }
1091     break;
1092 
1093   case Bytecodes::_invokevirtual:
1094   case Bytecodes::_invokespecial:
1095   case Bytecodes::_invokestatic:
1096   case Bytecodes::_invokedynamic:
1097   case Bytecodes::_invokeinterface:
1098     {
1099       bool ignored_will_link;
1100       ciSignature* declared_signature = nullptr;
1101       ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1102       assert(declared_signature != nullptr, "cannot be null");
1103       inputs   = declared_signature->arg_size_for_bc(code);
1104       int size = declared_signature->return_type()->size();
1105       depth = size - inputs;
1106     }
1107     break;
1108 
1109   case Bytecodes::_multianewarray:
1110     {
1111       ciBytecodeStream iter(method());
1112       iter.reset_to_bci(bci());
1113       iter.next();
1114       inputs = iter.get_dimensions();
1115       assert(rsize() == 1, "");
1116       depth = 1 - inputs;
1117     }
1118     break;
1119 
1120   case Bytecodes::_ireturn:
1121   case Bytecodes::_lreturn:
1122   case Bytecodes::_freturn:
1123   case Bytecodes::_dreturn:
1124   case Bytecodes::_areturn:
1125     assert(rsize() == -depth, "");
1126     inputs = -depth;
1127     break;
1128 
1129   case Bytecodes::_jsr:
1130   case Bytecodes::_jsr_w:
1131     inputs = 0;
1132     depth  = 1;                  // S.B. depth=1, not zero
1133     break;
1134 
1135   default:
1136     // bytecode produces a typed result
1137     inputs = rsize() - depth;
1138     assert(inputs >= 0, "");
1139     break;
1140   }
1141 
1142 #ifdef ASSERT
1143   // spot check
1144   int outputs = depth + inputs;
1145   assert(outputs >= 0, "sanity");
1146   switch (code) {
1147   case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1148   case Bytecodes::_athrow:    assert(inputs == 1 && outputs == 0, ""); break;
1149   case Bytecodes::_aload_0:   assert(inputs == 0 && outputs == 1, ""); break;
1150   case Bytecodes::_return:    assert(inputs == 0 && outputs == 0, ""); break;
1151   case Bytecodes::_drem:      assert(inputs == 4 && outputs == 2, ""); break;
1152   default:                    break;
1153   }
1154 #endif //ASSERT
1155 
1156   return true;
1157 }
1158 
1159 
1160 
1161 //------------------------------basic_plus_adr---------------------------------
1162 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1163   // short-circuit a common case
1164   if (offset == intcon(0))  return ptr;
1165   return _gvn.transform( new AddPNode(base, ptr, offset) );
1166 }
1167 
1168 Node* GraphKit::ConvI2L(Node* offset) {
1169   // short-circuit a common case
1170   jint offset_con = find_int_con(offset, Type::OffsetBot);
1171   if (offset_con != Type::OffsetBot) {
1172     return longcon((jlong) offset_con);
1173   }
1174   return _gvn.transform( new ConvI2LNode(offset));
1175 }
1176 
1177 Node* GraphKit::ConvI2UL(Node* offset) {
1178   juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1179   if (offset_con != (juint) Type::OffsetBot) {
1180     return longcon((julong) offset_con);
1181   }
1182   Node* conv = _gvn.transform( new ConvI2LNode(offset));
1183   Node* mask = _gvn.transform(ConLNode::make((julong) max_juint));
1184   return _gvn.transform( new AndLNode(conv, mask) );
1185 }
1186 
1187 Node* GraphKit::ConvL2I(Node* offset) {
1188   // short-circuit a common case
1189   jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1190   if (offset_con != (jlong)Type::OffsetBot) {
1191     return intcon((int) offset_con);
1192   }
1193   return _gvn.transform( new ConvL2INode(offset));
1194 }
1195 
1196 //-------------------------load_object_klass-----------------------------------
1197 Node* GraphKit::load_object_klass(Node* obj) {
1198   // Special-case a fresh allocation to avoid building nodes:
1199   Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1200   if (akls != nullptr)  return akls;
1201   Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1202   return _gvn.transform(LoadKlassNode::make(_gvn, nullptr, immutable_memory(), k_adr, TypeInstPtr::KLASS));
1203 }
1204 
1205 //-------------------------load_array_length-----------------------------------
1206 Node* GraphKit::load_array_length(Node* array) {
1207   // Special-case a fresh allocation to avoid building nodes:
1208   AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array);
1209   Node *alen;
1210   if (alloc == nullptr) {
1211     Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1212     alen = _gvn.transform( new LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1213   } else {
1214     alen = array_ideal_length(alloc, _gvn.type(array)->is_oopptr(), false);
1215   }
1216   return alen;
1217 }
1218 
1219 Node* GraphKit::array_ideal_length(AllocateArrayNode* alloc,
1220                                    const TypeOopPtr* oop_type,
1221                                    bool replace_length_in_map) {
1222   Node* length = alloc->Ideal_length();
1223   if (replace_length_in_map == false || map()->find_edge(length) >= 0) {
1224     Node* ccast = alloc->make_ideal_length(oop_type, &_gvn);
1225     if (ccast != length) {
1226       // do not transform ccast here, it might convert to top node for
1227       // negative array length and break assumptions in parsing stage.
1228       _gvn.set_type_bottom(ccast);
1229       record_for_igvn(ccast);
1230       if (replace_length_in_map) {
1231         replace_in_map(length, ccast);
1232       }
1233       return ccast;
1234     }
1235   }
1236   return length;
1237 }
1238 
1239 //------------------------------do_null_check----------------------------------
1240 // Helper function to do a null pointer check.  Returned value is
1241 // the incoming address with null casted away.  You are allowed to use the
1242 // not-null value only if you are control dependent on the test.
1243 #ifndef PRODUCT
1244 extern uint explicit_null_checks_inserted,
1245             explicit_null_checks_elided;
1246 #endif
1247 Node* GraphKit::null_check_common(Node* value, BasicType type,
1248                                   // optional arguments for variations:
1249                                   bool assert_null,
1250                                   Node* *null_control,
1251                                   bool speculative) {
1252   assert(!assert_null || null_control == nullptr, "not both at once");
1253   if (stopped())  return top();
1254   NOT_PRODUCT(explicit_null_checks_inserted++);
1255 
1256   // Construct null check
1257   Node *chk = nullptr;
1258   switch(type) {
1259     case T_LONG   : chk = new CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1260     case T_INT    : chk = new CmpINode(value, _gvn.intcon(0)); break;
1261     case T_ARRAY  : // fall through
1262       type = T_OBJECT;  // simplify further tests
1263     case T_OBJECT : {
1264       const Type *t = _gvn.type( value );
1265 
1266       const TypeOopPtr* tp = t->isa_oopptr();
1267       if (tp != nullptr && !tp->is_loaded()
1268           // Only for do_null_check, not any of its siblings:
1269           && !assert_null && null_control == nullptr) {
1270         // Usually, any field access or invocation on an unloaded oop type
1271         // will simply fail to link, since the statically linked class is
1272         // likely also to be unloaded.  However, in -Xcomp mode, sometimes
1273         // the static class is loaded but the sharper oop type is not.
1274         // Rather than checking for this obscure case in lots of places,
1275         // we simply observe that a null check on an unloaded class
1276         // will always be followed by a nonsense operation, so we
1277         // can just issue the uncommon trap here.
1278         // Our access to the unloaded class will only be correct
1279         // after it has been loaded and initialized, which requires
1280         // a trip through the interpreter.
1281         ciKlass* klass = tp->unloaded_klass();
1282 #ifndef PRODUCT
1283         if (WizardMode) { tty->print("Null check of unloaded "); klass->print(); tty->cr(); }
1284 #endif
1285         uncommon_trap(Deoptimization::Reason_unloaded,
1286                       Deoptimization::Action_reinterpret,
1287                       klass, "!loaded");
1288         return top();
1289       }
1290 
1291       if (assert_null) {
1292         // See if the type is contained in NULL_PTR.
1293         // If so, then the value is already null.
1294         if (t->higher_equal(TypePtr::NULL_PTR)) {
1295           NOT_PRODUCT(explicit_null_checks_elided++);
1296           return value;           // Elided null assert quickly!
1297         }
1298       } else {
1299         // See if mixing in the null pointer changes type.
1300         // If so, then the null pointer was not allowed in the original
1301         // type.  In other words, "value" was not-null.
1302         if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1303           // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1304           NOT_PRODUCT(explicit_null_checks_elided++);
1305           return value;           // Elided null check quickly!
1306         }
1307       }
1308       chk = new CmpPNode( value, null() );
1309       break;
1310     }
1311 
1312     default:
1313       fatal("unexpected type: %s", type2name(type));
1314   }
1315   assert(chk != nullptr, "sanity check");
1316   chk = _gvn.transform(chk);
1317 
1318   BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1319   BoolNode *btst = new BoolNode( chk, btest);
1320   Node   *tst = _gvn.transform( btst );
1321 
1322   //-----------
1323   // if peephole optimizations occurred, a prior test existed.
1324   // If a prior test existed, maybe it dominates as we can avoid this test.
1325   if (tst != btst && type == T_OBJECT) {
1326     // At this point we want to scan up the CFG to see if we can
1327     // find an identical test (and so avoid this test altogether).
1328     Node *cfg = control();
1329     int depth = 0;
1330     while( depth < 16 ) {       // Limit search depth for speed
1331       if( cfg->Opcode() == Op_IfTrue &&
1332           cfg->in(0)->in(1) == tst ) {
1333         // Found prior test.  Use "cast_not_null" to construct an identical
1334         // CastPP (and hence hash to) as already exists for the prior test.
1335         // Return that casted value.
1336         if (assert_null) {
1337           replace_in_map(value, null());
1338           return null();  // do not issue the redundant test
1339         }
1340         Node *oldcontrol = control();
1341         set_control(cfg);
1342         Node *res = cast_not_null(value);
1343         set_control(oldcontrol);
1344         NOT_PRODUCT(explicit_null_checks_elided++);
1345         return res;
1346       }
1347       cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1348       if (cfg == nullptr)  break;  // Quit at region nodes
1349       depth++;
1350     }
1351   }
1352 
1353   //-----------
1354   // Branch to failure if null
1355   float ok_prob = PROB_MAX;  // a priori estimate:  nulls never happen
1356   Deoptimization::DeoptReason reason;
1357   if (assert_null) {
1358     reason = Deoptimization::reason_null_assert(speculative);
1359   } else if (type == T_OBJECT) {
1360     reason = Deoptimization::reason_null_check(speculative);
1361   } else {
1362     reason = Deoptimization::Reason_div0_check;
1363   }
1364   // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1365   // ciMethodData::has_trap_at will return a conservative -1 if any
1366   // must-be-null assertion has failed.  This could cause performance
1367   // problems for a method after its first do_null_assert failure.
1368   // Consider using 'Reason_class_check' instead?
1369 
1370   // To cause an implicit null check, we set the not-null probability
1371   // to the maximum (PROB_MAX).  For an explicit check the probability
1372   // is set to a smaller value.
1373   if (null_control != nullptr || too_many_traps(reason)) {
1374     // probability is less likely
1375     ok_prob =  PROB_LIKELY_MAG(3);
1376   } else if (!assert_null &&
1377              (ImplicitNullCheckThreshold > 0) &&
1378              method() != nullptr &&
1379              (method()->method_data()->trap_count(reason)
1380               >= (uint)ImplicitNullCheckThreshold)) {
1381     ok_prob =  PROB_LIKELY_MAG(3);
1382   }
1383 
1384   if (null_control != nullptr) {
1385     IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1386     Node* null_true = _gvn.transform( new IfFalseNode(iff));
1387     set_control(      _gvn.transform( new IfTrueNode(iff)));
1388 #ifndef PRODUCT
1389     if (null_true == top()) {
1390       explicit_null_checks_elided++;
1391     }
1392 #endif
1393     (*null_control) = null_true;
1394   } else {
1395     BuildCutout unless(this, tst, ok_prob);
1396     // Check for optimizer eliding test at parse time
1397     if (stopped()) {
1398       // Failure not possible; do not bother making uncommon trap.
1399       NOT_PRODUCT(explicit_null_checks_elided++);
1400     } else if (assert_null) {
1401       uncommon_trap(reason,
1402                     Deoptimization::Action_make_not_entrant,
1403                     nullptr, "assert_null");
1404     } else {
1405       replace_in_map(value, zerocon(type));
1406       builtin_throw(reason);
1407     }
1408   }
1409 
1410   // Must throw exception, fall-thru not possible?
1411   if (stopped()) {
1412     return top();               // No result
1413   }
1414 
1415   if (assert_null) {
1416     // Cast obj to null on this path.
1417     replace_in_map(value, zerocon(type));
1418     return zerocon(type);
1419   }
1420 
1421   // Cast obj to not-null on this path, if there is no null_control.
1422   // (If there is a null_control, a non-null value may come back to haunt us.)
1423   if (type == T_OBJECT) {
1424     Node* cast = cast_not_null(value, false);
1425     if (null_control == nullptr || (*null_control) == top())
1426       replace_in_map(value, cast);
1427     value = cast;
1428   }
1429 
1430   return value;
1431 }
1432 
1433 
1434 //------------------------------cast_not_null----------------------------------
1435 // Cast obj to not-null on this path
1436 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1437   const Type *t = _gvn.type(obj);
1438   const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1439   // Object is already not-null?
1440   if( t == t_not_null ) return obj;
1441 
1442   Node* cast = new CastPPNode(control(), obj,t_not_null);
1443   cast = _gvn.transform( cast );
1444 
1445   // Scan for instances of 'obj' in the current JVM mapping.
1446   // These instances are known to be not-null after the test.
1447   if (do_replace_in_map)
1448     replace_in_map(obj, cast);
1449 
1450   return cast;                  // Return casted value
1451 }
1452 
1453 // Sometimes in intrinsics, we implicitly know an object is not null
1454 // (there's no actual null check) so we can cast it to not null. In
1455 // the course of optimizations, the input to the cast can become null.
1456 // In that case that data path will die and we need the control path
1457 // to become dead as well to keep the graph consistent. So we have to
1458 // add a check for null for which one branch can't be taken. It uses
1459 // an Opaque4 node that will cause the check to be removed after loop
1460 // opts so the test goes away and the compiled code doesn't execute a
1461 // useless check.
1462 Node* GraphKit::must_be_not_null(Node* value, bool do_replace_in_map) {
1463   if (!TypePtr::NULL_PTR->higher_equal(_gvn.type(value))) {
1464     return value;
1465   }
1466   Node* chk = _gvn.transform(new CmpPNode(value, null()));
1467   Node *tst = _gvn.transform(new BoolNode(chk, BoolTest::ne));
1468   Node* opaq = _gvn.transform(new Opaque4Node(C, tst, intcon(1)));
1469   IfNode *iff = new IfNode(control(), opaq, PROB_MAX, COUNT_UNKNOWN);
1470   _gvn.set_type(iff, iff->Value(&_gvn));
1471   Node *if_f = _gvn.transform(new IfFalseNode(iff));
1472   Node *frame = _gvn.transform(new ParmNode(C->start(), TypeFunc::FramePtr));
1473   Node* halt = _gvn.transform(new HaltNode(if_f, frame, "unexpected null in intrinsic"));
1474   C->root()->add_req(halt);
1475   Node *if_t = _gvn.transform(new IfTrueNode(iff));
1476   set_control(if_t);
1477   return cast_not_null(value, do_replace_in_map);
1478 }
1479 
1480 
1481 //--------------------------replace_in_map-------------------------------------
1482 void GraphKit::replace_in_map(Node* old, Node* neww) {
1483   if (old == neww) {
1484     return;
1485   }
1486 
1487   map()->replace_edge(old, neww);
1488 
1489   // Note: This operation potentially replaces any edge
1490   // on the map.  This includes locals, stack, and monitors
1491   // of the current (innermost) JVM state.
1492 
1493   // don't let inconsistent types from profiling escape this
1494   // method
1495 
1496   const Type* told = _gvn.type(old);
1497   const Type* tnew = _gvn.type(neww);
1498 
1499   if (!tnew->higher_equal(told)) {
1500     return;
1501   }
1502 
1503   map()->record_replaced_node(old, neww);
1504 }
1505 
1506 
1507 //=============================================================================
1508 //--------------------------------memory---------------------------------------
1509 Node* GraphKit::memory(uint alias_idx) {
1510   MergeMemNode* mem = merged_memory();
1511   Node* p = mem->memory_at(alias_idx);
1512   assert(p != mem->empty_memory(), "empty");
1513   _gvn.set_type(p, Type::MEMORY);  // must be mapped
1514   return p;
1515 }
1516 
1517 //-----------------------------reset_memory------------------------------------
1518 Node* GraphKit::reset_memory() {
1519   Node* mem = map()->memory();
1520   // do not use this node for any more parsing!
1521   debug_only( map()->set_memory((Node*)nullptr) );
1522   return _gvn.transform( mem );
1523 }
1524 
1525 //------------------------------set_all_memory---------------------------------
1526 void GraphKit::set_all_memory(Node* newmem) {
1527   Node* mergemem = MergeMemNode::make(newmem);
1528   gvn().set_type_bottom(mergemem);
1529   map()->set_memory(mergemem);
1530 }
1531 
1532 //------------------------------set_all_memory_call----------------------------
1533 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1534   Node* newmem = _gvn.transform( new ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1535   set_all_memory(newmem);
1536 }
1537 
1538 //=============================================================================
1539 //
1540 // parser factory methods for MemNodes
1541 //
1542 // These are layered on top of the factory methods in LoadNode and StoreNode,
1543 // and integrate with the parser's memory state and _gvn engine.
1544 //
1545 
1546 // factory methods in "int adr_idx"
1547 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1548                           int adr_idx,
1549                           MemNode::MemOrd mo,
1550                           LoadNode::ControlDependency control_dependency,
1551                           bool require_atomic_access,
1552                           bool unaligned,
1553                           bool mismatched,
1554                           bool unsafe,
1555                           uint8_t barrier_data) {
1556   assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1557   const TypePtr* adr_type = nullptr; // debug-mode-only argument
1558   debug_only(adr_type = C->get_adr_type(adr_idx));
1559   Node* mem = memory(adr_idx);
1560   Node* ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, require_atomic_access, unaligned, mismatched, unsafe, barrier_data);
1561   ld = _gvn.transform(ld);
1562   if (((bt == T_OBJECT) && C->do_escape_analysis()) || C->eliminate_boxing()) {
1563     // Improve graph before escape analysis and boxing elimination.
1564     record_for_igvn(ld);
1565     if (ld->is_DecodeN()) {
1566       // Also record the actual load (LoadN) in case ld is DecodeN
1567       assert(ld->in(1)->Opcode() == Op_LoadN, "Assumption invalid: input to DecodeN is not LoadN");
1568       record_for_igvn(ld->in(1));
1569     }
1570   }
1571   return ld;
1572 }
1573 
1574 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1575                                 int adr_idx,
1576                                 MemNode::MemOrd mo,
1577                                 bool require_atomic_access,
1578                                 bool unaligned,
1579                                 bool mismatched,
1580                                 bool unsafe,
1581                                 int barrier_data) {
1582   assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1583   const TypePtr* adr_type = nullptr;
1584   debug_only(adr_type = C->get_adr_type(adr_idx));
1585   Node *mem = memory(adr_idx);
1586   Node* st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo, require_atomic_access);
1587   if (unaligned) {
1588     st->as_Store()->set_unaligned_access();
1589   }
1590   if (mismatched) {
1591     st->as_Store()->set_mismatched_access();
1592   }
1593   if (unsafe) {
1594     st->as_Store()->set_unsafe_access();
1595   }
1596   st->as_Store()->set_barrier_data(barrier_data);
1597   st = _gvn.transform(st);
1598   set_memory(st, adr_idx);
1599   // Back-to-back stores can only remove intermediate store with DU info
1600   // so push on worklist for optimizer.
1601   if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1602     record_for_igvn(st);
1603 
1604   return st;
1605 }
1606 
1607 Node* GraphKit::access_store_at(Node* obj,
1608                                 Node* adr,
1609                                 const TypePtr* adr_type,
1610                                 Node* val,
1611                                 const Type* val_type,
1612                                 BasicType bt,
1613                                 DecoratorSet decorators) {
1614   // Transformation of a value which could be null pointer (CastPP #null)
1615   // could be delayed during Parse (for example, in adjust_map_after_if()).
1616   // Execute transformation here to avoid barrier generation in such case.
1617   if (_gvn.type(val) == TypePtr::NULL_PTR) {
1618     val = _gvn.makecon(TypePtr::NULL_PTR);
1619   }
1620 
1621   if (stopped()) {
1622     return top(); // Dead path ?
1623   }
1624 
1625   assert(val != nullptr, "not dead path");
1626 
1627   C2AccessValuePtr addr(adr, adr_type);
1628   C2AccessValue value(val, val_type);
1629   C2ParseAccess access(this, decorators | C2_WRITE_ACCESS, bt, obj, addr);
1630   if (access.is_raw()) {
1631     return _barrier_set->BarrierSetC2::store_at(access, value);
1632   } else {
1633     return _barrier_set->store_at(access, value);
1634   }
1635 }
1636 
1637 Node* GraphKit::access_load_at(Node* obj,   // containing obj
1638                                Node* adr,   // actual address to store val at
1639                                const TypePtr* adr_type,
1640                                const Type* val_type,
1641                                BasicType bt,
1642                                DecoratorSet decorators) {
1643   if (stopped()) {
1644     return top(); // Dead path ?
1645   }
1646 
1647   C2AccessValuePtr addr(adr, adr_type);
1648   C2ParseAccess access(this, decorators | C2_READ_ACCESS, bt, obj, addr);
1649   if (access.is_raw()) {
1650     return _barrier_set->BarrierSetC2::load_at(access, val_type);
1651   } else {
1652     return _barrier_set->load_at(access, val_type);
1653   }
1654 }
1655 
1656 Node* GraphKit::access_load(Node* adr,   // actual address to load val at
1657                             const Type* val_type,
1658                             BasicType bt,
1659                             DecoratorSet decorators) {
1660   if (stopped()) {
1661     return top(); // Dead path ?
1662   }
1663 
1664   C2AccessValuePtr addr(adr, adr->bottom_type()->is_ptr());
1665   C2ParseAccess access(this, decorators | C2_READ_ACCESS, bt, nullptr, addr);
1666   if (access.is_raw()) {
1667     return _barrier_set->BarrierSetC2::load_at(access, val_type);
1668   } else {
1669     return _barrier_set->load_at(access, val_type);
1670   }
1671 }
1672 
1673 Node* GraphKit::access_atomic_cmpxchg_val_at(Node* obj,
1674                                              Node* adr,
1675                                              const TypePtr* adr_type,
1676                                              int alias_idx,
1677                                              Node* expected_val,
1678                                              Node* new_val,
1679                                              const Type* value_type,
1680                                              BasicType bt,
1681                                              DecoratorSet decorators) {
1682   C2AccessValuePtr addr(adr, adr_type);
1683   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1684                         bt, obj, addr, alias_idx);
1685   if (access.is_raw()) {
1686     return _barrier_set->BarrierSetC2::atomic_cmpxchg_val_at(access, expected_val, new_val, value_type);
1687   } else {
1688     return _barrier_set->atomic_cmpxchg_val_at(access, expected_val, new_val, value_type);
1689   }
1690 }
1691 
1692 Node* GraphKit::access_atomic_cmpxchg_bool_at(Node* obj,
1693                                               Node* adr,
1694                                               const TypePtr* adr_type,
1695                                               int alias_idx,
1696                                               Node* expected_val,
1697                                               Node* new_val,
1698                                               const Type* value_type,
1699                                               BasicType bt,
1700                                               DecoratorSet decorators) {
1701   C2AccessValuePtr addr(adr, adr_type);
1702   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1703                         bt, obj, addr, alias_idx);
1704   if (access.is_raw()) {
1705     return _barrier_set->BarrierSetC2::atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type);
1706   } else {
1707     return _barrier_set->atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type);
1708   }
1709 }
1710 
1711 Node* GraphKit::access_atomic_xchg_at(Node* obj,
1712                                       Node* adr,
1713                                       const TypePtr* adr_type,
1714                                       int alias_idx,
1715                                       Node* new_val,
1716                                       const Type* value_type,
1717                                       BasicType bt,
1718                                       DecoratorSet decorators) {
1719   C2AccessValuePtr addr(adr, adr_type);
1720   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1721                         bt, obj, addr, alias_idx);
1722   if (access.is_raw()) {
1723     return _barrier_set->BarrierSetC2::atomic_xchg_at(access, new_val, value_type);
1724   } else {
1725     return _barrier_set->atomic_xchg_at(access, new_val, value_type);
1726   }
1727 }
1728 
1729 Node* GraphKit::access_atomic_add_at(Node* obj,
1730                                      Node* adr,
1731                                      const TypePtr* adr_type,
1732                                      int alias_idx,
1733                                      Node* new_val,
1734                                      const Type* value_type,
1735                                      BasicType bt,
1736                                      DecoratorSet decorators) {
1737   C2AccessValuePtr addr(adr, adr_type);
1738   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS, bt, obj, addr, alias_idx);
1739   if (access.is_raw()) {
1740     return _barrier_set->BarrierSetC2::atomic_add_at(access, new_val, value_type);
1741   } else {
1742     return _barrier_set->atomic_add_at(access, new_val, value_type);
1743   }
1744 }
1745 
1746 void GraphKit::access_clone(Node* src, Node* dst, Node* size, bool is_array) {
1747   return _barrier_set->clone(this, src, dst, size, is_array);
1748 }
1749 
1750 //-------------------------array_element_address-------------------------
1751 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1752                                       const TypeInt* sizetype, Node* ctrl) {
1753   uint shift  = exact_log2(type2aelembytes(elembt));
1754   uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1755 
1756   // short-circuit a common case (saves lots of confusing waste motion)
1757   jint idx_con = find_int_con(idx, -1);
1758   if (idx_con >= 0) {
1759     intptr_t offset = header + ((intptr_t)idx_con << shift);
1760     return basic_plus_adr(ary, offset);
1761   }
1762 
1763   // must be correct type for alignment purposes
1764   Node* base  = basic_plus_adr(ary, header);
1765   idx = Compile::conv_I2X_index(&_gvn, idx, sizetype, ctrl);
1766   Node* scale = _gvn.transform( new LShiftXNode(idx, intcon(shift)) );
1767   return basic_plus_adr(ary, base, scale);
1768 }
1769 
1770 //-------------------------load_array_element-------------------------
1771 Node* GraphKit::load_array_element(Node* ary, Node* idx, const TypeAryPtr* arytype, bool set_ctrl) {
1772   const Type* elemtype = arytype->elem();
1773   BasicType elembt = elemtype->array_element_basic_type();
1774   Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1775   if (elembt == T_NARROWOOP) {
1776     elembt = T_OBJECT; // To satisfy switch in LoadNode::make()
1777   }
1778   Node* ld = access_load_at(ary, adr, arytype, elemtype, elembt,
1779                             IN_HEAP | IS_ARRAY | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0));
1780   return ld;
1781 }
1782 
1783 //-------------------------set_arguments_for_java_call-------------------------
1784 // Arguments (pre-popped from the stack) are taken from the JVMS.
1785 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1786   // Add the call arguments:
1787   uint nargs = call->method()->arg_size();
1788   for (uint i = 0; i < nargs; i++) {
1789     Node* arg = argument(i);
1790     call->init_req(i + TypeFunc::Parms, arg);
1791   }
1792 }
1793 
1794 //---------------------------set_edges_for_java_call---------------------------
1795 // Connect a newly created call into the current JVMS.
1796 // A return value node (if any) is returned from set_edges_for_java_call.
1797 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1798 
1799   // Add the predefined inputs:
1800   call->init_req( TypeFunc::Control, control() );
1801   call->init_req( TypeFunc::I_O    , i_o() );
1802   call->init_req( TypeFunc::Memory , reset_memory() );
1803   call->init_req( TypeFunc::FramePtr, frameptr() );
1804   call->init_req( TypeFunc::ReturnAdr, top() );
1805 
1806   add_safepoint_edges(call, must_throw);
1807 
1808   Node* xcall = _gvn.transform(call);
1809 
1810   if (xcall == top()) {
1811     set_control(top());
1812     return;
1813   }
1814   assert(xcall == call, "call identity is stable");
1815 
1816   // Re-use the current map to produce the result.
1817 
1818   set_control(_gvn.transform(new ProjNode(call, TypeFunc::Control)));
1819   set_i_o(    _gvn.transform(new ProjNode(call, TypeFunc::I_O    , separate_io_proj)));
1820   set_all_memory_call(xcall, separate_io_proj);
1821 
1822   //return xcall;   // no need, caller already has it
1823 }
1824 
1825 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj, bool deoptimize) {
1826   if (stopped())  return top();  // maybe the call folded up?
1827 
1828   // Capture the return value, if any.
1829   Node* ret;
1830   if (call->method() == nullptr ||
1831       call->method()->return_type()->basic_type() == T_VOID)
1832         ret = top();
1833   else  ret = _gvn.transform(new ProjNode(call, TypeFunc::Parms));
1834 
1835   // Note:  Since any out-of-line call can produce an exception,
1836   // we always insert an I_O projection from the call into the result.
1837 
1838   make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj, deoptimize);
1839 
1840   if (separate_io_proj) {
1841     // The caller requested separate projections be used by the fall
1842     // through and exceptional paths, so replace the projections for
1843     // the fall through path.
1844     set_i_o(_gvn.transform( new ProjNode(call, TypeFunc::I_O) ));
1845     set_all_memory(_gvn.transform( new ProjNode(call, TypeFunc::Memory) ));
1846   }
1847   return ret;
1848 }
1849 
1850 //--------------------set_predefined_input_for_runtime_call--------------------
1851 // Reading and setting the memory state is way conservative here.
1852 // The real problem is that I am not doing real Type analysis on memory,
1853 // so I cannot distinguish card mark stores from other stores.  Across a GC
1854 // point the Store Barrier and the card mark memory has to agree.  I cannot
1855 // have a card mark store and its barrier split across the GC point from
1856 // either above or below.  Here I get that to happen by reading ALL of memory.
1857 // A better answer would be to separate out card marks from other memory.
1858 // For now, return the input memory state, so that it can be reused
1859 // after the call, if this call has restricted memory effects.
1860 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call, Node* narrow_mem) {
1861   // Set fixed predefined input arguments
1862   Node* memory = reset_memory();
1863   Node* m = narrow_mem == nullptr ? memory : narrow_mem;
1864   call->init_req( TypeFunc::Control,   control()  );
1865   call->init_req( TypeFunc::I_O,       top()      ); // does no i/o
1866   call->init_req( TypeFunc::Memory,    m          ); // may gc ptrs
1867   call->init_req( TypeFunc::FramePtr,  frameptr() );
1868   call->init_req( TypeFunc::ReturnAdr, top()      );
1869   return memory;
1870 }
1871 
1872 //-------------------set_predefined_output_for_runtime_call--------------------
1873 // Set control and memory (not i_o) from the call.
1874 // If keep_mem is not null, use it for the output state,
1875 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1876 // If hook_mem is null, this call produces no memory effects at all.
1877 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1878 // then only that memory slice is taken from the call.
1879 // In the last case, we must put an appropriate memory barrier before
1880 // the call, so as to create the correct anti-dependencies on loads
1881 // preceding the call.
1882 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1883                                                       Node* keep_mem,
1884                                                       const TypePtr* hook_mem) {
1885   // no i/o
1886   set_control(_gvn.transform( new ProjNode(call,TypeFunc::Control) ));
1887   if (keep_mem) {
1888     // First clone the existing memory state
1889     set_all_memory(keep_mem);
1890     if (hook_mem != nullptr) {
1891       // Make memory for the call
1892       Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
1893       // Set the RawPtr memory state only.  This covers all the heap top/GC stuff
1894       // We also use hook_mem to extract specific effects from arraycopy stubs.
1895       set_memory(mem, hook_mem);
1896     }
1897     // ...else the call has NO memory effects.
1898 
1899     // Make sure the call advertises its memory effects precisely.
1900     // This lets us build accurate anti-dependences in gcm.cpp.
1901     assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1902            "call node must be constructed correctly");
1903   } else {
1904     assert(hook_mem == nullptr, "");
1905     // This is not a "slow path" call; all memory comes from the call.
1906     set_all_memory_call(call);
1907   }
1908 }
1909 
1910 // Keep track of MergeMems feeding into other MergeMems
1911 static void add_mergemem_users_to_worklist(Unique_Node_List& wl, Node* mem) {
1912   if (!mem->is_MergeMem()) {
1913     return;
1914   }
1915   for (SimpleDUIterator i(mem); i.has_next(); i.next()) {
1916     Node* use = i.get();
1917     if (use->is_MergeMem()) {
1918       wl.push(use);
1919     }
1920   }
1921 }
1922 
1923 // Replace the call with the current state of the kit.
1924 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes) {
1925   JVMState* ejvms = nullptr;
1926   if (has_exceptions()) {
1927     ejvms = transfer_exceptions_into_jvms();
1928   }
1929 
1930   ReplacedNodes replaced_nodes = map()->replaced_nodes();
1931   ReplacedNodes replaced_nodes_exception;
1932   Node* ex_ctl = top();
1933 
1934   SafePointNode* final_state = stop();
1935 
1936   // Find all the needed outputs of this call
1937   CallProjections callprojs;
1938   call->extract_projections(&callprojs, true);
1939 
1940   Unique_Node_List wl;
1941   Node* init_mem = call->in(TypeFunc::Memory);
1942   Node* final_mem = final_state->in(TypeFunc::Memory);
1943   Node* final_ctl = final_state->in(TypeFunc::Control);
1944   Node* final_io = final_state->in(TypeFunc::I_O);
1945 
1946   // Replace all the old call edges with the edges from the inlining result
1947   if (callprojs.fallthrough_catchproj != nullptr) {
1948     C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
1949   }
1950   if (callprojs.fallthrough_memproj != nullptr) {
1951     if (final_mem->is_MergeMem()) {
1952       // Parser's exits MergeMem was not transformed but may be optimized
1953       final_mem = _gvn.transform(final_mem);
1954     }
1955     C->gvn_replace_by(callprojs.fallthrough_memproj,   final_mem);
1956     add_mergemem_users_to_worklist(wl, final_mem);
1957   }
1958   if (callprojs.fallthrough_ioproj != nullptr) {
1959     C->gvn_replace_by(callprojs.fallthrough_ioproj,    final_io);
1960   }
1961 
1962   // Replace the result with the new result if it exists and is used
1963   if (callprojs.resproj != nullptr && result != nullptr) {
1964     C->gvn_replace_by(callprojs.resproj, result);
1965   }
1966 
1967   if (ejvms == nullptr) {
1968     // No exception edges to simply kill off those paths
1969     if (callprojs.catchall_catchproj != nullptr) {
1970       C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1971     }
1972     if (callprojs.catchall_memproj != nullptr) {
1973       C->gvn_replace_by(callprojs.catchall_memproj,   C->top());
1974     }
1975     if (callprojs.catchall_ioproj != nullptr) {
1976       C->gvn_replace_by(callprojs.catchall_ioproj,    C->top());
1977     }
1978     // Replace the old exception object with top
1979     if (callprojs.exobj != nullptr) {
1980       C->gvn_replace_by(callprojs.exobj, C->top());
1981     }
1982   } else {
1983     GraphKit ekit(ejvms);
1984 
1985     // Load my combined exception state into the kit, with all phis transformed:
1986     SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1987     replaced_nodes_exception = ex_map->replaced_nodes();
1988 
1989     Node* ex_oop = ekit.use_exception_state(ex_map);
1990 
1991     if (callprojs.catchall_catchproj != nullptr) {
1992       C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1993       ex_ctl = ekit.control();
1994     }
1995     if (callprojs.catchall_memproj != nullptr) {
1996       Node* ex_mem = ekit.reset_memory();
1997       C->gvn_replace_by(callprojs.catchall_memproj,   ex_mem);
1998       add_mergemem_users_to_worklist(wl, ex_mem);
1999     }
2000     if (callprojs.catchall_ioproj != nullptr) {
2001       C->gvn_replace_by(callprojs.catchall_ioproj,    ekit.i_o());
2002     }
2003 
2004     // Replace the old exception object with the newly created one
2005     if (callprojs.exobj != nullptr) {
2006       C->gvn_replace_by(callprojs.exobj, ex_oop);
2007     }
2008   }
2009 
2010   // Disconnect the call from the graph
2011   call->disconnect_inputs(C);
2012   C->gvn_replace_by(call, C->top());
2013 
2014   // Clean up any MergeMems that feed other MergeMems since the
2015   // optimizer doesn't like that.
2016   while (wl.size() > 0) {
2017     _gvn.transform(wl.pop());
2018   }
2019 
2020   if (callprojs.fallthrough_catchproj != nullptr && !final_ctl->is_top() && do_replaced_nodes) {
2021     replaced_nodes.apply(C, final_ctl);
2022   }
2023   if (!ex_ctl->is_top() && do_replaced_nodes) {
2024     replaced_nodes_exception.apply(C, ex_ctl);
2025   }
2026 }
2027 
2028 
2029 //------------------------------increment_counter------------------------------
2030 // for statistics: increment a VM counter by 1
2031 
2032 void GraphKit::increment_counter(address counter_addr) {
2033   Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
2034   increment_counter(adr1);
2035 }
2036 
2037 void GraphKit::increment_counter(Node* counter_addr) {
2038   int adr_type = Compile::AliasIdxRaw;
2039   Node* ctrl = control();
2040   Node* cnt  = make_load(ctrl, counter_addr, TypeLong::LONG, T_LONG, adr_type, MemNode::unordered);
2041   Node* incr = _gvn.transform(new AddLNode(cnt, _gvn.longcon(1)));
2042   store_to_memory(ctrl, counter_addr, incr, T_LONG, adr_type, MemNode::unordered);
2043 }
2044 
2045 
2046 //------------------------------uncommon_trap----------------------------------
2047 // Bail out to the interpreter in mid-method.  Implemented by calling the
2048 // uncommon_trap blob.  This helper function inserts a runtime call with the
2049 // right debug info.
2050 Node* GraphKit::uncommon_trap(int trap_request,
2051                              ciKlass* klass, const char* comment,
2052                              bool must_throw,
2053                              bool keep_exact_action) {
2054   if (failing())  stop();
2055   if (stopped())  return nullptr; // trap reachable?
2056 
2057   // Note:  If ProfileTraps is true, and if a deopt. actually
2058   // occurs here, the runtime will make sure an MDO exists.  There is
2059   // no need to call method()->ensure_method_data() at this point.
2060 
2061   // Set the stack pointer to the right value for reexecution:
2062   set_sp(reexecute_sp());
2063 
2064 #ifdef ASSERT
2065   if (!must_throw) {
2066     // Make sure the stack has at least enough depth to execute
2067     // the current bytecode.
2068     int inputs, ignored_depth;
2069     if (compute_stack_effects(inputs, ignored_depth)) {
2070       assert(sp() >= inputs, "must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
2071              Bytecodes::name(java_bc()), sp(), inputs);
2072     }
2073   }
2074 #endif
2075 
2076   Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
2077   Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
2078 
2079   switch (action) {
2080   case Deoptimization::Action_maybe_recompile:
2081   case Deoptimization::Action_reinterpret:
2082     // Temporary fix for 6529811 to allow virtual calls to be sure they
2083     // get the chance to go from mono->bi->mega
2084     if (!keep_exact_action &&
2085         Deoptimization::trap_request_index(trap_request) < 0 &&
2086         too_many_recompiles(reason)) {
2087       // This BCI is causing too many recompilations.
2088       if (C->log() != nullptr) {
2089         C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'",
2090                 Deoptimization::trap_reason_name(reason),
2091                 Deoptimization::trap_action_name(action));
2092       }
2093       action = Deoptimization::Action_none;
2094       trap_request = Deoptimization::make_trap_request(reason, action);
2095     } else {
2096       C->set_trap_can_recompile(true);
2097     }
2098     break;
2099   case Deoptimization::Action_make_not_entrant:
2100     C->set_trap_can_recompile(true);
2101     break;
2102   case Deoptimization::Action_none:
2103   case Deoptimization::Action_make_not_compilable:
2104     break;
2105   default:
2106 #ifdef ASSERT
2107     fatal("unknown action %d: %s", action, Deoptimization::trap_action_name(action));
2108 #endif
2109     break;
2110   }
2111 
2112   if (TraceOptoParse) {
2113     char buf[100];
2114     tty->print_cr("Uncommon trap %s at bci:%d",
2115                   Deoptimization::format_trap_request(buf, sizeof(buf),
2116                                                       trap_request), bci());
2117   }
2118 
2119   CompileLog* log = C->log();
2120   if (log != nullptr) {
2121     int kid = (klass == nullptr)? -1: log->identify(klass);
2122     log->begin_elem("uncommon_trap bci='%d'", bci());
2123     char buf[100];
2124     log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2125                                                           trap_request));
2126     if (kid >= 0)         log->print(" klass='%d'", kid);
2127     if (comment != nullptr)  log->print(" comment='%s'", comment);
2128     log->end_elem();
2129   }
2130 
2131   // Make sure any guarding test views this path as very unlikely
2132   Node *i0 = control()->in(0);
2133   if (i0 != nullptr && i0->is_If()) {        // Found a guarding if test?
2134     IfNode *iff = i0->as_If();
2135     float f = iff->_prob;   // Get prob
2136     if (control()->Opcode() == Op_IfTrue) {
2137       if (f > PROB_UNLIKELY_MAG(4))
2138         iff->_prob = PROB_MIN;
2139     } else {
2140       if (f < PROB_LIKELY_MAG(4))
2141         iff->_prob = PROB_MAX;
2142     }
2143   }
2144 
2145   // Clear out dead values from the debug info.
2146   kill_dead_locals();
2147 
2148   // Now insert the uncommon trap subroutine call
2149   address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point();
2150   const TypePtr* no_memory_effects = nullptr;
2151   // Pass the index of the class to be loaded
2152   Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2153                                  (must_throw ? RC_MUST_THROW : 0),
2154                                  OptoRuntime::uncommon_trap_Type(),
2155                                  call_addr, "uncommon_trap", no_memory_effects,
2156                                  intcon(trap_request));
2157   assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2158          "must extract request correctly from the graph");
2159   assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2160 
2161   call->set_req(TypeFunc::ReturnAdr, returnadr());
2162   // The debug info is the only real input to this call.
2163 
2164   // Halt-and-catch fire here.  The above call should never return!
2165   HaltNode* halt = new HaltNode(control(), frameptr(), "uncommon trap returned which should never happen"
2166                                                        PRODUCT_ONLY(COMMA /*reachable*/false));
2167   _gvn.set_type_bottom(halt);
2168   root()->add_req(halt);
2169 
2170   stop_and_kill_map();
2171   return call;
2172 }
2173 
2174 
2175 //--------------------------just_allocated_object------------------------------
2176 // Report the object that was just allocated.
2177 // It must be the case that there are no intervening safepoints.
2178 // We use this to determine if an object is so "fresh" that
2179 // it does not require card marks.
2180 Node* GraphKit::just_allocated_object(Node* current_control) {
2181   Node* ctrl = current_control;
2182   // Object::<init> is invoked after allocation, most of invoke nodes
2183   // will be reduced, but a region node is kept in parse time, we check
2184   // the pattern and skip the region node if it degraded to a copy.
2185   if (ctrl != nullptr && ctrl->is_Region() && ctrl->req() == 2 &&
2186       ctrl->as_Region()->is_copy()) {
2187     ctrl = ctrl->as_Region()->is_copy();
2188   }
2189   if (C->recent_alloc_ctl() == ctrl) {
2190    return C->recent_alloc_obj();
2191   }
2192   return nullptr;
2193 }
2194 
2195 
2196 /**
2197  * Record profiling data exact_kls for Node n with the type system so
2198  * that it can propagate it (speculation)
2199  *
2200  * @param n          node that the type applies to
2201  * @param exact_kls  type from profiling
2202  * @param maybe_null did profiling see null?
2203  *
2204  * @return           node with improved type
2205  */
2206 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind) {
2207   const Type* current_type = _gvn.type(n);
2208   assert(UseTypeSpeculation, "type speculation must be on");
2209 
2210   const TypePtr* speculative = current_type->speculative();
2211 
2212   // Should the klass from the profile be recorded in the speculative type?
2213   if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2214     const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls, Type::trust_interfaces);
2215     const TypeOopPtr* xtype = tklass->as_instance_type();
2216     assert(xtype->klass_is_exact(), "Should be exact");
2217     // Any reason to believe n is not null (from this profiling or a previous one)?
2218     assert(ptr_kind != ProfileAlwaysNull, "impossible here");
2219     const TypePtr* ptr = (ptr_kind == ProfileMaybeNull && current_type->speculative_maybe_null()) ? TypePtr::BOTTOM : TypePtr::NOTNULL;
2220     // record the new speculative type's depth
2221     speculative = xtype->cast_to_ptr_type(ptr->ptr())->is_ptr();
2222     speculative = speculative->with_inline_depth(jvms()->depth());
2223   } else if (current_type->would_improve_ptr(ptr_kind)) {
2224     // Profiling report that null was never seen so we can change the
2225     // speculative type to non null ptr.
2226     if (ptr_kind == ProfileAlwaysNull) {
2227       speculative = TypePtr::NULL_PTR;
2228     } else {
2229       assert(ptr_kind == ProfileNeverNull, "nothing else is an improvement");
2230       const TypePtr* ptr = TypePtr::NOTNULL;
2231       if (speculative != nullptr) {
2232         speculative = speculative->cast_to_ptr_type(ptr->ptr())->is_ptr();
2233       } else {
2234         speculative = ptr;
2235       }
2236     }
2237   }
2238 
2239   if (speculative != current_type->speculative()) {
2240     // Build a type with a speculative type (what we think we know
2241     // about the type but will need a guard when we use it)
2242     const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2243     // We're changing the type, we need a new CheckCast node to carry
2244     // the new type. The new type depends on the control: what
2245     // profiling tells us is only valid from here as far as we can
2246     // tell.
2247     Node* cast = new CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2248     cast = _gvn.transform(cast);
2249     replace_in_map(n, cast);
2250     n = cast;
2251   }
2252 
2253   return n;
2254 }
2255 
2256 /**
2257  * Record profiling data from receiver profiling at an invoke with the
2258  * type system so that it can propagate it (speculation)
2259  *
2260  * @param n  receiver node
2261  *
2262  * @return   node with improved type
2263  */
2264 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2265   if (!UseTypeSpeculation) {
2266     return n;
2267   }
2268   ciKlass* exact_kls = profile_has_unique_klass();
2269   ProfilePtrKind ptr_kind = ProfileMaybeNull;
2270   if ((java_bc() == Bytecodes::_checkcast ||
2271        java_bc() == Bytecodes::_instanceof ||
2272        java_bc() == Bytecodes::_aastore) &&
2273       method()->method_data()->is_mature()) {
2274     ciProfileData* data = method()->method_data()->bci_to_data(bci());
2275     if (data != nullptr) {
2276       if (!data->as_BitData()->null_seen()) {
2277         ptr_kind = ProfileNeverNull;
2278       } else {
2279         assert(data->is_ReceiverTypeData(), "bad profile data type");
2280         ciReceiverTypeData* call = (ciReceiverTypeData*)data->as_ReceiverTypeData();
2281         uint i = 0;
2282         for (; i < call->row_limit(); i++) {
2283           ciKlass* receiver = call->receiver(i);
2284           if (receiver != nullptr) {
2285             break;
2286           }
2287         }
2288         ptr_kind = (i == call->row_limit()) ? ProfileAlwaysNull : ProfileMaybeNull;
2289       }
2290     }
2291   }
2292   return record_profile_for_speculation(n, exact_kls, ptr_kind);
2293 }
2294 
2295 /**
2296  * Record profiling data from argument profiling at an invoke with the
2297  * type system so that it can propagate it (speculation)
2298  *
2299  * @param dest_method  target method for the call
2300  * @param bc           what invoke bytecode is this?
2301  */
2302 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2303   if (!UseTypeSpeculation) {
2304     return;
2305   }
2306   const TypeFunc* tf    = TypeFunc::make(dest_method);
2307   int             nargs = tf->domain()->cnt() - TypeFunc::Parms;
2308   int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2309   for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2310     const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2311     if (is_reference_type(targ->basic_type())) {
2312       ProfilePtrKind ptr_kind = ProfileMaybeNull;
2313       ciKlass* better_type = nullptr;
2314       if (method()->argument_profiled_type(bci(), i, better_type, ptr_kind)) {
2315         record_profile_for_speculation(argument(j), better_type, ptr_kind);
2316       }
2317       i++;
2318     }
2319   }
2320 }
2321 
2322 /**
2323  * Record profiling data from parameter profiling at an invoke with
2324  * the type system so that it can propagate it (speculation)
2325  */
2326 void GraphKit::record_profiled_parameters_for_speculation() {
2327   if (!UseTypeSpeculation) {
2328     return;
2329   }
2330   for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2331     if (_gvn.type(local(i))->isa_oopptr()) {
2332       ProfilePtrKind ptr_kind = ProfileMaybeNull;
2333       ciKlass* better_type = nullptr;
2334       if (method()->parameter_profiled_type(j, better_type, ptr_kind)) {
2335         record_profile_for_speculation(local(i), better_type, ptr_kind);
2336       }
2337       j++;
2338     }
2339   }
2340 }
2341 
2342 /**
2343  * Record profiling data from return value profiling at an invoke with
2344  * the type system so that it can propagate it (speculation)
2345  */
2346 void GraphKit::record_profiled_return_for_speculation() {
2347   if (!UseTypeSpeculation) {
2348     return;
2349   }
2350   ProfilePtrKind ptr_kind = ProfileMaybeNull;
2351   ciKlass* better_type = nullptr;
2352   if (method()->return_profiled_type(bci(), better_type, ptr_kind)) {
2353     // If profiling reports a single type for the return value,
2354     // feed it to the type system so it can propagate it as a
2355     // speculative type
2356     record_profile_for_speculation(stack(sp()-1), better_type, ptr_kind);
2357   }
2358 }
2359 
2360 void GraphKit::round_double_arguments(ciMethod* dest_method) {
2361   if (Matcher::strict_fp_requires_explicit_rounding) {
2362     // (Note:  TypeFunc::make has a cache that makes this fast.)
2363     const TypeFunc* tf    = TypeFunc::make(dest_method);
2364     int             nargs = tf->domain()->cnt() - TypeFunc::Parms;
2365     for (int j = 0; j < nargs; j++) {
2366       const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2367       if (targ->basic_type() == T_DOUBLE) {
2368         // If any parameters are doubles, they must be rounded before
2369         // the call, dprecision_rounding does gvn.transform
2370         Node *arg = argument(j);
2371         arg = dprecision_rounding(arg);
2372         set_argument(j, arg);
2373       }
2374     }
2375   }
2376 }
2377 
2378 // rounding for strict float precision conformance
2379 Node* GraphKit::precision_rounding(Node* n) {
2380   if (Matcher::strict_fp_requires_explicit_rounding) {
2381 #ifdef IA32
2382     if (UseSSE == 0) {
2383       return _gvn.transform(new RoundFloatNode(0, n));
2384     }
2385 #else
2386     Unimplemented();
2387 #endif // IA32
2388   }
2389   return n;
2390 }
2391 
2392 // rounding for strict double precision conformance
2393 Node* GraphKit::dprecision_rounding(Node *n) {
2394   if (Matcher::strict_fp_requires_explicit_rounding) {
2395 #ifdef IA32
2396     if (UseSSE < 2) {
2397       return _gvn.transform(new RoundDoubleNode(0, n));
2398     }
2399 #else
2400     Unimplemented();
2401 #endif // IA32
2402   }
2403   return n;
2404 }
2405 
2406 //=============================================================================
2407 // Generate a fast path/slow path idiom.  Graph looks like:
2408 // [foo] indicates that 'foo' is a parameter
2409 //
2410 //              [in]     null
2411 //                 \    /
2412 //                  CmpP
2413 //                  Bool ne
2414 //                   If
2415 //                  /  \
2416 //              True    False-<2>
2417 //              / |
2418 //             /  cast_not_null
2419 //           Load  |    |   ^
2420 //        [fast_test]   |   |
2421 // gvn to   opt_test    |   |
2422 //          /    \      |  <1>
2423 //      True     False  |
2424 //        |         \\  |
2425 //   [slow_call]     \[fast_result]
2426 //    Ctl   Val       \      \
2427 //     |               \      \
2428 //    Catch       <1>   \      \
2429 //   /    \        ^     \      \
2430 //  Ex    No_Ex    |      \      \
2431 //  |       \   \  |       \ <2>  \
2432 //  ...      \  [slow_res] |  |    \   [null_result]
2433 //            \         \--+--+---  |  |
2434 //             \           | /    \ | /
2435 //              --------Region     Phi
2436 //
2437 //=============================================================================
2438 // Code is structured as a series of driver functions all called 'do_XXX' that
2439 // call a set of helper functions.  Helper functions first, then drivers.
2440 
2441 //------------------------------null_check_oop---------------------------------
2442 // Null check oop.  Set null-path control into Region in slot 3.
2443 // Make a cast-not-nullness use the other not-null control.  Return cast.
2444 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2445                                bool never_see_null,
2446                                bool safe_for_replace,
2447                                bool speculative) {
2448   // Initial null check taken path
2449   (*null_control) = top();
2450   Node* cast = null_check_common(value, T_OBJECT, false, null_control, speculative);
2451 
2452   // Generate uncommon_trap:
2453   if (never_see_null && (*null_control) != top()) {
2454     // If we see an unexpected null at a check-cast we record it and force a
2455     // recompile; the offending check-cast will be compiled to handle nulls.
2456     // If we see more than one offending BCI, then all checkcasts in the
2457     // method will be compiled to handle nulls.
2458     PreserveJVMState pjvms(this);
2459     set_control(*null_control);
2460     replace_in_map(value, null());
2461     Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculative);
2462     uncommon_trap(reason,
2463                   Deoptimization::Action_make_not_entrant);
2464     (*null_control) = top();    // null path is dead
2465   }
2466   if ((*null_control) == top() && safe_for_replace) {
2467     replace_in_map(value, cast);
2468   }
2469 
2470   // Cast away null-ness on the result
2471   return cast;
2472 }
2473 
2474 //------------------------------opt_iff----------------------------------------
2475 // Optimize the fast-check IfNode.  Set the fast-path region slot 2.
2476 // Return slow-path control.
2477 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2478   IfNode *opt_iff = _gvn.transform(iff)->as_If();
2479 
2480   // Fast path taken; set region slot 2
2481   Node *fast_taken = _gvn.transform( new IfFalseNode(opt_iff) );
2482   region->init_req(2,fast_taken); // Capture fast-control
2483 
2484   // Fast path not-taken, i.e. slow path
2485   Node *slow_taken = _gvn.transform( new IfTrueNode(opt_iff) );
2486   return slow_taken;
2487 }
2488 
2489 //-----------------------------make_runtime_call-------------------------------
2490 Node* GraphKit::make_runtime_call(int flags,
2491                                   const TypeFunc* call_type, address call_addr,
2492                                   const char* call_name,
2493                                   const TypePtr* adr_type,
2494                                   // The following parms are all optional.
2495                                   // The first null ends the list.
2496                                   Node* parm0, Node* parm1,
2497                                   Node* parm2, Node* parm3,
2498                                   Node* parm4, Node* parm5,
2499                                   Node* parm6, Node* parm7) {
2500   assert(call_addr != nullptr, "must not call null targets");
2501 
2502   // Slow-path call
2503   bool is_leaf = !(flags & RC_NO_LEAF);
2504   bool has_io  = (!is_leaf && !(flags & RC_NO_IO));
2505   if (call_name == nullptr) {
2506     assert(!is_leaf, "must supply name for leaf");
2507     call_name = OptoRuntime::stub_name(call_addr);
2508   }
2509   CallNode* call;
2510   if (!is_leaf) {
2511     call = new CallStaticJavaNode(call_type, call_addr, call_name, adr_type);
2512   } else if (flags & RC_NO_FP) {
2513     call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2514   } else  if (flags & RC_VECTOR){
2515     uint num_bits = call_type->range()->field_at(TypeFunc::Parms)->is_vect()->length_in_bytes() * BitsPerByte;
2516     call = new CallLeafVectorNode(call_type, call_addr, call_name, adr_type, num_bits);
2517   } else {
2518     call = new CallLeafNode(call_type, call_addr, call_name, adr_type);
2519   }
2520 
2521   // The following is similar to set_edges_for_java_call,
2522   // except that the memory effects of the call are restricted to AliasIdxRaw.
2523 
2524   // Slow path call has no side-effects, uses few values
2525   bool wide_in  = !(flags & RC_NARROW_MEM);
2526   bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2527 
2528   Node* prev_mem = nullptr;
2529   if (wide_in) {
2530     prev_mem = set_predefined_input_for_runtime_call(call);
2531   } else {
2532     assert(!wide_out, "narrow in => narrow out");
2533     Node* narrow_mem = memory(adr_type);
2534     prev_mem = set_predefined_input_for_runtime_call(call, narrow_mem);
2535   }
2536 
2537   // Hook each parm in order.  Stop looking at the first null.
2538   if (parm0 != nullptr) { call->init_req(TypeFunc::Parms+0, parm0);
2539   if (parm1 != nullptr) { call->init_req(TypeFunc::Parms+1, parm1);
2540   if (parm2 != nullptr) { call->init_req(TypeFunc::Parms+2, parm2);
2541   if (parm3 != nullptr) { call->init_req(TypeFunc::Parms+3, parm3);
2542   if (parm4 != nullptr) { call->init_req(TypeFunc::Parms+4, parm4);
2543   if (parm5 != nullptr) { call->init_req(TypeFunc::Parms+5, parm5);
2544   if (parm6 != nullptr) { call->init_req(TypeFunc::Parms+6, parm6);
2545   if (parm7 != nullptr) { call->init_req(TypeFunc::Parms+7, parm7);
2546   /* close each nested if ===> */  } } } } } } } }
2547   assert(call->in(call->req()-1) != nullptr, "must initialize all parms");
2548 
2549   if (!is_leaf) {
2550     // Non-leaves can block and take safepoints:
2551     add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2552   }
2553   // Non-leaves can throw exceptions:
2554   if (has_io) {
2555     call->set_req(TypeFunc::I_O, i_o());
2556   }
2557 
2558   if (flags & RC_UNCOMMON) {
2559     // Set the count to a tiny probability.  Cf. Estimate_Block_Frequency.
2560     // (An "if" probability corresponds roughly to an unconditional count.
2561     // Sort of.)
2562     call->set_cnt(PROB_UNLIKELY_MAG(4));
2563   }
2564 
2565   Node* c = _gvn.transform(call);
2566   assert(c == call, "cannot disappear");
2567 
2568   if (wide_out) {
2569     // Slow path call has full side-effects.
2570     set_predefined_output_for_runtime_call(call);
2571   } else {
2572     // Slow path call has few side-effects, and/or sets few values.
2573     set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2574   }
2575 
2576   if (has_io) {
2577     set_i_o(_gvn.transform(new ProjNode(call, TypeFunc::I_O)));
2578   }
2579   return call;
2580 
2581 }
2582 
2583 // i2b
2584 Node* GraphKit::sign_extend_byte(Node* in) {
2585   Node* tmp = _gvn.transform(new LShiftINode(in, _gvn.intcon(24)));
2586   return _gvn.transform(new RShiftINode(tmp, _gvn.intcon(24)));
2587 }
2588 
2589 // i2s
2590 Node* GraphKit::sign_extend_short(Node* in) {
2591   Node* tmp = _gvn.transform(new LShiftINode(in, _gvn.intcon(16)));
2592   return _gvn.transform(new RShiftINode(tmp, _gvn.intcon(16)));
2593 }
2594 
2595 //------------------------------merge_memory-----------------------------------
2596 // Merge memory from one path into the current memory state.
2597 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2598   for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2599     Node* old_slice = mms.force_memory();
2600     Node* new_slice = mms.memory2();
2601     if (old_slice != new_slice) {
2602       PhiNode* phi;
2603       if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) {
2604         if (mms.is_empty()) {
2605           // clone base memory Phi's inputs for this memory slice
2606           assert(old_slice == mms.base_memory(), "sanity");
2607           phi = PhiNode::make(region, nullptr, Type::MEMORY, mms.adr_type(C));
2608           _gvn.set_type(phi, Type::MEMORY);
2609           for (uint i = 1; i < phi->req(); i++) {
2610             phi->init_req(i, old_slice->in(i));
2611           }
2612         } else {
2613           phi = old_slice->as_Phi(); // Phi was generated already
2614         }
2615       } else {
2616         phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2617         _gvn.set_type(phi, Type::MEMORY);
2618       }
2619       phi->set_req(new_path, new_slice);
2620       mms.set_memory(phi);
2621     }
2622   }
2623 }
2624 
2625 //------------------------------make_slow_call_ex------------------------------
2626 // Make the exception handler hookups for the slow call
2627 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) {
2628   if (stopped())  return;
2629 
2630   // Make a catch node with just two handlers:  fall-through and catch-all
2631   Node* i_o  = _gvn.transform( new ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2632   Node* catc = _gvn.transform( new CatchNode(control(), i_o, 2) );
2633   Node* norm = new CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci);
2634   _gvn.set_type_bottom(norm);
2635   C->record_for_igvn(norm);
2636   Node* excp = _gvn.transform( new CatchProjNode(catc, CatchProjNode::catch_all_index,    CatchProjNode::no_handler_bci) );
2637 
2638   { PreserveJVMState pjvms(this);
2639     set_control(excp);
2640     set_i_o(i_o);
2641 
2642     if (excp != top()) {
2643       if (deoptimize) {
2644         // Deoptimize if an exception is caught. Don't construct exception state in this case.
2645         uncommon_trap(Deoptimization::Reason_unhandled,
2646                       Deoptimization::Action_none);
2647       } else {
2648         // Create an exception state also.
2649         // Use an exact type if the caller has a specific exception.
2650         const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2651         Node*       ex_oop  = new CreateExNode(ex_type, control(), i_o);
2652         add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2653       }
2654     }
2655   }
2656 
2657   // Get the no-exception control from the CatchNode.
2658   set_control(norm);
2659 }
2660 
2661 static IfNode* gen_subtype_check_compare(Node* ctrl, Node* in1, Node* in2, BoolTest::mask test, float p, PhaseGVN& gvn, BasicType bt) {
2662   Node* cmp = nullptr;
2663   switch(bt) {
2664   case T_INT: cmp = new CmpINode(in1, in2); break;
2665   case T_ADDRESS: cmp = new CmpPNode(in1, in2); break;
2666   default: fatal("unexpected comparison type %s", type2name(bt));
2667   }
2668   cmp = gvn.transform(cmp);
2669   Node* bol = gvn.transform(new BoolNode(cmp, test));
2670   IfNode* iff = new IfNode(ctrl, bol, p, COUNT_UNKNOWN);
2671   gvn.transform(iff);
2672   if (!bol->is_Con()) gvn.record_for_igvn(iff);
2673   return iff;
2674 }
2675 
2676 //-------------------------------gen_subtype_check-----------------------------
2677 // Generate a subtyping check.  Takes as input the subtype and supertype.
2678 // Returns 2 values: sets the default control() to the true path and returns
2679 // the false path.  Only reads invariant memory; sets no (visible) memory.
2680 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2681 // but that's not exposed to the optimizer.  This call also doesn't take in an
2682 // Object; if you wish to check an Object you need to load the Object's class
2683 // prior to coming here.
2684 Node* Phase::gen_subtype_check(Node* subklass, Node* superklass, Node** ctrl, Node* mem, PhaseGVN& gvn,
2685                                ciMethod* method, int bci) {
2686   Compile* C = gvn.C;
2687   if ((*ctrl)->is_top()) {
2688     return C->top();
2689   }
2690 
2691   // Fast check for identical types, perhaps identical constants.
2692   // The types can even be identical non-constants, in cases
2693   // involving Array.newInstance, Object.clone, etc.
2694   if (subklass == superklass)
2695     return C->top();             // false path is dead; no test needed.
2696 
2697   if (gvn.type(superklass)->singleton()) {
2698     const TypeKlassPtr* superk = gvn.type(superklass)->is_klassptr();
2699     const TypeKlassPtr* subk   = gvn.type(subklass)->is_klassptr();
2700 
2701     // In the common case of an exact superklass, try to fold up the
2702     // test before generating code.  You may ask, why not just generate
2703     // the code and then let it fold up?  The answer is that the generated
2704     // code will necessarily include null checks, which do not always
2705     // completely fold away.  If they are also needless, then they turn
2706     // into a performance loss.  Example:
2707     //    Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2708     // Here, the type of 'fa' is often exact, so the store check
2709     // of fa[1]=x will fold up, without testing the nullness of x.
2710     switch (C->static_subtype_check(superk, subk)) {
2711     case Compile::SSC_always_false:
2712       {
2713         Node* always_fail = *ctrl;
2714         *ctrl = gvn.C->top();
2715         return always_fail;
2716       }
2717     case Compile::SSC_always_true:
2718       return C->top();
2719     case Compile::SSC_easy_test:
2720       {
2721         // Just do a direct pointer compare and be done.
2722         IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_STATIC_FREQUENT, gvn, T_ADDRESS);
2723         *ctrl = gvn.transform(new IfTrueNode(iff));
2724         return gvn.transform(new IfFalseNode(iff));
2725       }
2726     case Compile::SSC_full_test:
2727       break;
2728     default:
2729       ShouldNotReachHere();
2730     }
2731   }
2732 
2733   // %%% Possible further optimization:  Even if the superklass is not exact,
2734   // if the subklass is the unique subtype of the superklass, the check
2735   // will always succeed.  We could leave a dependency behind to ensure this.
2736 
2737   // First load the super-klass's check-offset
2738   Node *p1 = gvn.transform(new AddPNode(superklass, superklass, gvn.MakeConX(in_bytes(Klass::super_check_offset_offset()))));
2739   Node* m = C->immutable_memory();
2740   Node *chk_off = gvn.transform(new LoadINode(nullptr, m, p1, gvn.type(p1)->is_ptr(), TypeInt::INT, MemNode::unordered));
2741   int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2742   const TypeInt* chk_off_t = chk_off->Value(&gvn)->isa_int();
2743   int chk_off_con = (chk_off_t != nullptr && chk_off_t->is_con()) ? chk_off_t->get_con() : cacheoff_con;
2744   bool might_be_cache = (chk_off_con == cacheoff_con);
2745 
2746   // Load from the sub-klass's super-class display list, or a 1-word cache of
2747   // the secondary superclass list, or a failing value with a sentinel offset
2748   // if the super-klass is an interface or exceptionally deep in the Java
2749   // hierarchy and we have to scan the secondary superclass list the hard way.
2750   // Worst-case type is a little odd: null is allowed as a result (usually
2751   // klass loads can never produce a null).
2752   Node *chk_off_X = chk_off;
2753 #ifdef _LP64
2754   chk_off_X = gvn.transform(new ConvI2LNode(chk_off_X));
2755 #endif
2756   Node *p2 = gvn.transform(new AddPNode(subklass,subklass,chk_off_X));
2757   // For some types like interfaces the following loadKlass is from a 1-word
2758   // cache which is mutable so can't use immutable memory.  Other
2759   // types load from the super-class display table which is immutable.
2760   Node *kmem = C->immutable_memory();
2761   // secondary_super_cache is not immutable but can be treated as such because:
2762   // - no ideal node writes to it in a way that could cause an
2763   //   incorrect/missed optimization of the following Load.
2764   // - it's a cache so, worse case, not reading the latest value
2765   //   wouldn't cause incorrect execution
2766   if (might_be_cache && mem != nullptr) {
2767     kmem = mem->is_MergeMem() ? mem->as_MergeMem()->memory_at(C->get_alias_index(gvn.type(p2)->is_ptr())) : mem;
2768   }
2769   Node *nkls = gvn.transform(LoadKlassNode::make(gvn, nullptr, kmem, p2, gvn.type(p2)->is_ptr(), TypeInstKlassPtr::OBJECT_OR_NULL));
2770 
2771   // Compile speed common case: ARE a subtype and we canNOT fail
2772   if (superklass == nkls) {
2773     return C->top();             // false path is dead; no test needed.
2774   }
2775 
2776   // Gather the various success & failures here
2777   RegionNode* r_not_subtype = new RegionNode(3);
2778   gvn.record_for_igvn(r_not_subtype);
2779   RegionNode* r_ok_subtype = new RegionNode(4);
2780   gvn.record_for_igvn(r_ok_subtype);
2781 
2782   // If we might perform an expensive check, first try to take advantage of profile data that was attached to the
2783   // SubTypeCheck node
2784   if (might_be_cache && method != nullptr && VM_Version::profile_all_receivers_at_type_check()) {
2785     ciCallProfile profile = method->call_profile_at_bci(bci);
2786     float total_prob = 0;
2787     for (int i = 0; profile.has_receiver(i); ++i) {
2788       float prob = profile.receiver_prob(i);
2789       total_prob += prob;
2790     }
2791     if (total_prob * 100. >= TypeProfileSubTypeCheckCommonThreshold) {
2792       const TypeKlassPtr* superk = gvn.type(superklass)->is_klassptr();
2793       for (int i = 0; profile.has_receiver(i); ++i) {
2794         ciKlass* klass = profile.receiver(i);
2795         const TypeKlassPtr* klass_t = TypeKlassPtr::make(klass);
2796         Compile::SubTypeCheckResult result = C->static_subtype_check(superk, klass_t);
2797         if (result != Compile::SSC_always_true && result != Compile::SSC_always_false) {
2798           continue;
2799         }
2800         float prob = profile.receiver_prob(i);
2801         ConNode* klass_node = gvn.makecon(klass_t);
2802         IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, klass_node, BoolTest::eq, prob, gvn, T_ADDRESS);
2803         Node* iftrue = gvn.transform(new IfTrueNode(iff));
2804 
2805         if (result == Compile::SSC_always_true) {
2806           r_ok_subtype->add_req(iftrue);
2807         } else {
2808           assert(result == Compile::SSC_always_false, "");
2809           r_not_subtype->add_req(iftrue);
2810         }
2811         *ctrl = gvn.transform(new IfFalseNode(iff));
2812       }
2813     }
2814   }
2815 
2816   // See if we get an immediate positive hit.  Happens roughly 83% of the
2817   // time.  Test to see if the value loaded just previously from the subklass
2818   // is exactly the superklass.
2819   IfNode *iff1 = gen_subtype_check_compare(*ctrl, superklass, nkls, BoolTest::eq, PROB_LIKELY(0.83f), gvn, T_ADDRESS);
2820   Node *iftrue1 = gvn.transform( new IfTrueNode (iff1));
2821   *ctrl = gvn.transform(new IfFalseNode(iff1));
2822 
2823   // Compile speed common case: Check for being deterministic right now.  If
2824   // chk_off is a constant and not equal to cacheoff then we are NOT a
2825   // subklass.  In this case we need exactly the 1 test above and we can
2826   // return those results immediately.
2827   if (!might_be_cache) {
2828     Node* not_subtype_ctrl = *ctrl;
2829     *ctrl = iftrue1; // We need exactly the 1 test above
2830     PhaseIterGVN* igvn = gvn.is_IterGVN();
2831     if (igvn != nullptr) {
2832       igvn->remove_globally_dead_node(r_ok_subtype);
2833       igvn->remove_globally_dead_node(r_not_subtype);
2834     }
2835     return not_subtype_ctrl;
2836   }
2837 
2838   r_ok_subtype->init_req(1, iftrue1);
2839 
2840   // Check for immediate negative hit.  Happens roughly 11% of the time (which
2841   // is roughly 63% of the remaining cases).  Test to see if the loaded
2842   // check-offset points into the subklass display list or the 1-element
2843   // cache.  If it points to the display (and NOT the cache) and the display
2844   // missed then it's not a subtype.
2845   Node *cacheoff = gvn.intcon(cacheoff_con);
2846   IfNode *iff2 = gen_subtype_check_compare(*ctrl, chk_off, cacheoff, BoolTest::ne, PROB_LIKELY(0.63f), gvn, T_INT);
2847   r_not_subtype->init_req(1, gvn.transform(new IfTrueNode (iff2)));
2848   *ctrl = gvn.transform(new IfFalseNode(iff2));
2849 
2850   // Check for self.  Very rare to get here, but it is taken 1/3 the time.
2851   // No performance impact (too rare) but allows sharing of secondary arrays
2852   // which has some footprint reduction.
2853   IfNode *iff3 = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_LIKELY(0.36f), gvn, T_ADDRESS);
2854   r_ok_subtype->init_req(2, gvn.transform(new IfTrueNode(iff3)));
2855   *ctrl = gvn.transform(new IfFalseNode(iff3));
2856 
2857   // -- Roads not taken here: --
2858   // We could also have chosen to perform the self-check at the beginning
2859   // of this code sequence, as the assembler does.  This would not pay off
2860   // the same way, since the optimizer, unlike the assembler, can perform
2861   // static type analysis to fold away many successful self-checks.
2862   // Non-foldable self checks work better here in second position, because
2863   // the initial primary superclass check subsumes a self-check for most
2864   // types.  An exception would be a secondary type like array-of-interface,
2865   // which does not appear in its own primary supertype display.
2866   // Finally, we could have chosen to move the self-check into the
2867   // PartialSubtypeCheckNode, and from there out-of-line in a platform
2868   // dependent manner.  But it is worthwhile to have the check here,
2869   // where it can be perhaps be optimized.  The cost in code space is
2870   // small (register compare, branch).
2871 
2872   // Now do a linear scan of the secondary super-klass array.  Again, no real
2873   // performance impact (too rare) but it's gotta be done.
2874   // Since the code is rarely used, there is no penalty for moving it
2875   // out of line, and it can only improve I-cache density.
2876   // The decision to inline or out-of-line this final check is platform
2877   // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2878   Node* psc = gvn.transform(
2879     new PartialSubtypeCheckNode(*ctrl, subklass, superklass));
2880 
2881   IfNode *iff4 = gen_subtype_check_compare(*ctrl, psc, gvn.zerocon(T_OBJECT), BoolTest::ne, PROB_FAIR, gvn, T_ADDRESS);
2882   r_not_subtype->init_req(2, gvn.transform(new IfTrueNode (iff4)));
2883   r_ok_subtype ->init_req(3, gvn.transform(new IfFalseNode(iff4)));
2884 
2885   // Return false path; set default control to true path.
2886   *ctrl = gvn.transform(r_ok_subtype);
2887   return gvn.transform(r_not_subtype);
2888 }
2889 
2890 Node* GraphKit::gen_subtype_check(Node* obj_or_subklass, Node* superklass) {
2891   bool expand_subtype_check = C->post_loop_opts_phase() ||   // macro node expansion is over
2892                               ExpandSubTypeCheckAtParseTime; // forced expansion
2893   if (expand_subtype_check) {
2894     MergeMemNode* mem = merged_memory();
2895     Node* ctrl = control();
2896     Node* subklass = obj_or_subklass;
2897     if (!_gvn.type(obj_or_subklass)->isa_klassptr()) {
2898       subklass = load_object_klass(obj_or_subklass);
2899     }
2900 
2901     Node* n = Phase::gen_subtype_check(subklass, superklass, &ctrl, mem, _gvn, method(), bci());
2902     set_control(ctrl);
2903     return n;
2904   }
2905 
2906   Node* check = _gvn.transform(new SubTypeCheckNode(C, obj_or_subklass, superklass, method(), bci()));
2907   Node* bol = _gvn.transform(new BoolNode(check, BoolTest::eq));
2908   IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN);
2909   set_control(_gvn.transform(new IfTrueNode(iff)));
2910   return _gvn.transform(new IfFalseNode(iff));
2911 }
2912 
2913 // Profile-driven exact type check:
2914 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2915                                     float prob,
2916                                     Node* *casted_receiver) {
2917   assert(!klass->is_interface(), "no exact type check on interfaces");
2918 
2919   const TypeKlassPtr* tklass = TypeKlassPtr::make(klass, Type::trust_interfaces);
2920   Node* recv_klass = load_object_klass(receiver);
2921   Node* want_klass = makecon(tklass);
2922   Node* cmp = _gvn.transform(new CmpPNode(recv_klass, want_klass));
2923   Node* bol = _gvn.transform(new BoolNode(cmp, BoolTest::eq));
2924   IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2925   set_control( _gvn.transform(new IfTrueNode (iff)));
2926   Node* fail = _gvn.transform(new IfFalseNode(iff));
2927 
2928   if (!stopped()) {
2929     const TypeOopPtr* receiver_type = _gvn.type(receiver)->isa_oopptr();
2930     const TypeOopPtr* recvx_type = tklass->as_instance_type();
2931     assert(recvx_type->klass_is_exact(), "");
2932 
2933     if (!receiver_type->higher_equal(recvx_type)) { // ignore redundant casts
2934       // Subsume downstream occurrences of receiver with a cast to
2935       // recv_xtype, since now we know what the type will be.
2936       Node* cast = new CheckCastPPNode(control(), receiver, recvx_type);
2937       (*casted_receiver) = _gvn.transform(cast);
2938       assert(!(*casted_receiver)->is_top(), "that path should be unreachable");
2939       // (User must make the replace_in_map call.)
2940     }
2941   }
2942 
2943   return fail;
2944 }
2945 
2946 //------------------------------subtype_check_receiver-------------------------
2947 Node* GraphKit::subtype_check_receiver(Node* receiver, ciKlass* klass,
2948                                        Node** casted_receiver) {
2949   const TypeKlassPtr* tklass = TypeKlassPtr::make(klass, Type::trust_interfaces)->try_improve();
2950   Node* want_klass = makecon(tklass);
2951 
2952   Node* slow_ctl = gen_subtype_check(receiver, want_klass);
2953 
2954   // Ignore interface type information until interface types are properly tracked.
2955   if (!stopped() && !klass->is_interface()) {
2956     const TypeOopPtr* receiver_type = _gvn.type(receiver)->isa_oopptr();
2957     const TypeOopPtr* recv_type = tklass->cast_to_exactness(false)->is_klassptr()->as_instance_type();
2958     if (!receiver_type->higher_equal(recv_type)) { // ignore redundant casts
2959       Node* cast = new CheckCastPPNode(control(), receiver, recv_type);
2960       (*casted_receiver) = _gvn.transform(cast);
2961     }
2962   }
2963 
2964   return slow_ctl;
2965 }
2966 
2967 //------------------------------seems_never_null-------------------------------
2968 // Use null_seen information if it is available from the profile.
2969 // If we see an unexpected null at a type check we record it and force a
2970 // recompile; the offending check will be recompiled to handle nulls.
2971 // If we see several offending BCIs, then all checks in the
2972 // method will be recompiled.
2973 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data, bool& speculating) {
2974   speculating = !_gvn.type(obj)->speculative_maybe_null();
2975   Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculating);
2976   if (UncommonNullCast               // Cutout for this technique
2977       && obj != null()               // And not the -Xcomp stupid case?
2978       && !too_many_traps(reason)
2979       ) {
2980     if (speculating) {
2981       return true;
2982     }
2983     if (data == nullptr)
2984       // Edge case:  no mature data.  Be optimistic here.
2985       return true;
2986     // If the profile has not seen a null, assume it won't happen.
2987     assert(java_bc() == Bytecodes::_checkcast ||
2988            java_bc() == Bytecodes::_instanceof ||
2989            java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
2990     return !data->as_BitData()->null_seen();
2991   }
2992   speculating = false;
2993   return false;
2994 }
2995 
2996 void GraphKit::guard_klass_being_initialized(Node* klass) {
2997   int init_state_off = in_bytes(InstanceKlass::init_state_offset());
2998   Node* adr = basic_plus_adr(top(), klass, init_state_off);
2999   Node* init_state = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3000                                     adr->bottom_type()->is_ptr(), TypeInt::BYTE,
3001                                     T_BYTE, MemNode::unordered);
3002   init_state = _gvn.transform(init_state);
3003 
3004   Node* being_initialized_state = makecon(TypeInt::make(InstanceKlass::being_initialized));
3005 
3006   Node* chk = _gvn.transform(new CmpINode(being_initialized_state, init_state));
3007   Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3008 
3009   { BuildCutout unless(this, tst, PROB_MAX);
3010     uncommon_trap(Deoptimization::Reason_initialized, Deoptimization::Action_reinterpret);
3011   }
3012 }
3013 
3014 void GraphKit::guard_init_thread(Node* klass) {
3015   int init_thread_off = in_bytes(InstanceKlass::init_thread_offset());
3016   Node* adr = basic_plus_adr(top(), klass, init_thread_off);
3017 
3018   Node* init_thread = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3019                                      adr->bottom_type()->is_ptr(), TypePtr::NOTNULL,
3020                                      T_ADDRESS, MemNode::unordered);
3021   init_thread = _gvn.transform(init_thread);
3022 
3023   Node* cur_thread = _gvn.transform(new ThreadLocalNode());
3024 
3025   Node* chk = _gvn.transform(new CmpPNode(cur_thread, init_thread));
3026   Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3027 
3028   { BuildCutout unless(this, tst, PROB_MAX);
3029     uncommon_trap(Deoptimization::Reason_uninitialized, Deoptimization::Action_none);
3030   }
3031 }
3032 
3033 void GraphKit::clinit_barrier(ciInstanceKlass* ik, ciMethod* context) {
3034   if (ik->is_being_initialized()) {
3035     if (C->needs_clinit_barrier(ik, context)) {
3036       Node* klass = makecon(TypeKlassPtr::make(ik));
3037       guard_klass_being_initialized(klass);
3038       guard_init_thread(klass);
3039       insert_mem_bar(Op_MemBarCPUOrder);
3040     }
3041   } else if (ik->is_initialized()) {
3042     return; // no barrier needed
3043   } else {
3044     uncommon_trap(Deoptimization::Reason_uninitialized,
3045                   Deoptimization::Action_reinterpret,
3046                   nullptr);
3047   }
3048 }
3049 
3050 //------------------------maybe_cast_profiled_receiver-------------------------
3051 // If the profile has seen exactly one type, narrow to exactly that type.
3052 // Subsequent type checks will always fold up.
3053 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
3054                                              const TypeKlassPtr* require_klass,
3055                                              ciKlass* spec_klass,
3056                                              bool safe_for_replace) {
3057   if (!UseTypeProfile || !TypeProfileCasts) return nullptr;
3058 
3059   Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != nullptr);
3060 
3061   // Make sure we haven't already deoptimized from this tactic.
3062   if (too_many_traps_or_recompiles(reason))
3063     return nullptr;
3064 
3065   // (No, this isn't a call, but it's enough like a virtual call
3066   // to use the same ciMethod accessor to get the profile info...)
3067   // If we have a speculative type use it instead of profiling (which
3068   // may not help us)
3069   ciKlass* exact_kls = spec_klass == nullptr ? profile_has_unique_klass() : spec_klass;
3070   if (exact_kls != nullptr) {// no cast failures here
3071     if (require_klass == nullptr ||
3072         C->static_subtype_check(require_klass, TypeKlassPtr::make(exact_kls, Type::trust_interfaces)) == Compile::SSC_always_true) {
3073       // If we narrow the type to match what the type profile sees or
3074       // the speculative type, we can then remove the rest of the
3075       // cast.
3076       // This is a win, even if the exact_kls is very specific,
3077       // because downstream operations, such as method calls,
3078       // will often benefit from the sharper type.
3079       Node* exact_obj = not_null_obj; // will get updated in place...
3080       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
3081                                             &exact_obj);
3082       { PreserveJVMState pjvms(this);
3083         set_control(slow_ctl);
3084         uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile);
3085       }
3086       if (safe_for_replace) {
3087         replace_in_map(not_null_obj, exact_obj);
3088       }
3089       return exact_obj;
3090     }
3091     // assert(ssc == Compile::SSC_always_true)... except maybe the profile lied to us.
3092   }
3093 
3094   return nullptr;
3095 }
3096 
3097 /**
3098  * Cast obj to type and emit guard unless we had too many traps here
3099  * already
3100  *
3101  * @param obj       node being casted
3102  * @param type      type to cast the node to
3103  * @param not_null  true if we know node cannot be null
3104  */
3105 Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
3106                                         ciKlass* type,
3107                                         bool not_null) {
3108   if (stopped()) {
3109     return obj;
3110   }
3111 
3112   // type is null if profiling tells us this object is always null
3113   if (type != nullptr) {
3114     Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
3115     Deoptimization::DeoptReason null_reason = Deoptimization::Reason_speculate_null_check;
3116 
3117     if (!too_many_traps_or_recompiles(null_reason) &&
3118         !too_many_traps_or_recompiles(class_reason)) {
3119       Node* not_null_obj = nullptr;
3120       // not_null is true if we know the object is not null and
3121       // there's no need for a null check
3122       if (!not_null) {
3123         Node* null_ctl = top();
3124         not_null_obj = null_check_oop(obj, &null_ctl, true, true, true);
3125         assert(null_ctl->is_top(), "no null control here");
3126       } else {
3127         not_null_obj = obj;
3128       }
3129 
3130       Node* exact_obj = not_null_obj;
3131       ciKlass* exact_kls = type;
3132       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
3133                                             &exact_obj);
3134       {
3135         PreserveJVMState pjvms(this);
3136         set_control(slow_ctl);
3137         uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile);
3138       }
3139       replace_in_map(not_null_obj, exact_obj);
3140       obj = exact_obj;
3141     }
3142   } else {
3143     if (!too_many_traps_or_recompiles(Deoptimization::Reason_null_assert)) {
3144       Node* exact_obj = null_assert(obj);
3145       replace_in_map(obj, exact_obj);
3146       obj = exact_obj;
3147     }
3148   }
3149   return obj;
3150 }
3151 
3152 //-------------------------------gen_instanceof--------------------------------
3153 // Generate an instance-of idiom.  Used by both the instance-of bytecode
3154 // and the reflective instance-of call.
3155 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
3156   kill_dead_locals();           // Benefit all the uncommon traps
3157   assert( !stopped(), "dead parse path should be checked in callers" );
3158   assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
3159          "must check for not-null not-dead klass in callers");
3160 
3161   // Make the merge point
3162   enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
3163   RegionNode* region = new RegionNode(PATH_LIMIT);
3164   Node*       phi    = new PhiNode(region, TypeInt::BOOL);
3165   C->set_has_split_ifs(true); // Has chance for split-if optimization
3166 
3167   ciProfileData* data = nullptr;
3168   if (java_bc() == Bytecodes::_instanceof) {  // Only for the bytecode
3169     data = method()->method_data()->bci_to_data(bci());
3170   }
3171   bool speculative_not_null = false;
3172   bool never_see_null = (ProfileDynamicTypes  // aggressive use of profile
3173                          && seems_never_null(obj, data, speculative_not_null));
3174 
3175   // Null check; get casted pointer; set region slot 3
3176   Node* null_ctl = top();
3177   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3178 
3179   // If not_null_obj is dead, only null-path is taken
3180   if (stopped()) {              // Doing instance-of on a null?
3181     set_control(null_ctl);
3182     return intcon(0);
3183   }
3184   region->init_req(_null_path, null_ctl);
3185   phi   ->init_req(_null_path, intcon(0)); // Set null path value
3186   if (null_ctl == top()) {
3187     // Do this eagerly, so that pattern matches like is_diamond_phi
3188     // will work even during parsing.
3189     assert(_null_path == PATH_LIMIT-1, "delete last");
3190     region->del_req(_null_path);
3191     phi   ->del_req(_null_path);
3192   }
3193 
3194   // Do we know the type check always succeed?
3195   bool known_statically = false;
3196   if (_gvn.type(superklass)->singleton()) {
3197     const TypeKlassPtr* superk = _gvn.type(superklass)->is_klassptr();
3198     const TypeKlassPtr* subk = _gvn.type(obj)->is_oopptr()->as_klass_type();
3199     if (subk->is_loaded()) {
3200       int static_res = C->static_subtype_check(superk, subk);
3201       known_statically = (static_res == Compile::SSC_always_true || static_res == Compile::SSC_always_false);
3202     }
3203   }
3204 
3205   if (!known_statically) {
3206     const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3207     // We may not have profiling here or it may not help us. If we
3208     // have a speculative type use it to perform an exact cast.
3209     ciKlass* spec_obj_type = obj_type->speculative_type();
3210     if (spec_obj_type != nullptr || (ProfileDynamicTypes && data != nullptr)) {
3211       Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, nullptr, spec_obj_type, safe_for_replace);
3212       if (stopped()) {            // Profile disagrees with this path.
3213         set_control(null_ctl);    // Null is the only remaining possibility.
3214         return intcon(0);
3215       }
3216       if (cast_obj != nullptr) {
3217         not_null_obj = cast_obj;
3218       }
3219     }
3220   }
3221 
3222   // Generate the subtype check
3223   Node* not_subtype_ctrl = gen_subtype_check(not_null_obj, superklass);
3224 
3225   // Plug in the success path to the general merge in slot 1.
3226   region->init_req(_obj_path, control());
3227   phi   ->init_req(_obj_path, intcon(1));
3228 
3229   // Plug in the failing path to the general merge in slot 2.
3230   region->init_req(_fail_path, not_subtype_ctrl);
3231   phi   ->init_req(_fail_path, intcon(0));
3232 
3233   // Return final merged results
3234   set_control( _gvn.transform(region) );
3235   record_for_igvn(region);
3236 
3237   // If we know the type check always succeeds then we don't use the
3238   // profiling data at this bytecode. Don't lose it, feed it to the
3239   // type system as a speculative type.
3240   if (safe_for_replace) {
3241     Node* casted_obj = record_profiled_receiver_for_speculation(obj);
3242     replace_in_map(obj, casted_obj);
3243   }
3244 
3245   return _gvn.transform(phi);
3246 }
3247 
3248 //-------------------------------gen_checkcast---------------------------------
3249 // Generate a checkcast idiom.  Used by both the checkcast bytecode and the
3250 // array store bytecode.  Stack must be as-if BEFORE doing the bytecode so the
3251 // uncommon-trap paths work.  Adjust stack after this call.
3252 // If failure_control is supplied and not null, it is filled in with
3253 // the control edge for the cast failure.  Otherwise, an appropriate
3254 // uncommon trap or exception is thrown.
3255 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
3256                               Node* *failure_control) {
3257   kill_dead_locals();           // Benefit all the uncommon traps
3258   const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr()->try_improve();
3259   const TypeOopPtr *toop = tk->cast_to_exactness(false)->as_instance_type();
3260 
3261   // Fast cutout:  Check the case that the cast is vacuously true.
3262   // This detects the common cases where the test will short-circuit
3263   // away completely.  We do this before we perform the null check,
3264   // because if the test is going to turn into zero code, we don't
3265   // want a residual null check left around.  (Causes a slowdown,
3266   // for example, in some objArray manipulations, such as a[i]=a[j].)
3267   if (tk->singleton()) {
3268     const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
3269     if (objtp != nullptr) {
3270       switch (C->static_subtype_check(tk, objtp->as_klass_type())) {
3271       case Compile::SSC_always_true:
3272         // If we know the type check always succeed then we don't use
3273         // the profiling data at this bytecode. Don't lose it, feed it
3274         // to the type system as a speculative type.
3275         return record_profiled_receiver_for_speculation(obj);
3276       case Compile::SSC_always_false:
3277         // It needs a null check because a null will *pass* the cast check.
3278         // A non-null value will always produce an exception.
3279         if (!objtp->maybe_null()) {
3280           bool is_aastore = (java_bc() == Bytecodes::_aastore);
3281           Deoptimization::DeoptReason reason = is_aastore ?
3282             Deoptimization::Reason_array_check : Deoptimization::Reason_class_check;
3283           builtin_throw(reason);
3284           return top();
3285         } else if (!too_many_traps_or_recompiles(Deoptimization::Reason_null_assert)) {
3286           return null_assert(obj);
3287         }
3288         break; // Fall through to full check
3289       default:
3290         break;
3291       }
3292     }
3293   }
3294 
3295   ciProfileData* data = nullptr;
3296   bool safe_for_replace = false;
3297   if (failure_control == nullptr) {        // use MDO in regular case only
3298     assert(java_bc() == Bytecodes::_aastore ||
3299            java_bc() == Bytecodes::_checkcast,
3300            "interpreter profiles type checks only for these BCs");
3301     data = method()->method_data()->bci_to_data(bci());
3302     safe_for_replace = true;
3303   }
3304 
3305   // Make the merge point
3306   enum { _obj_path = 1, _null_path, PATH_LIMIT };
3307   RegionNode* region = new RegionNode(PATH_LIMIT);
3308   Node*       phi    = new PhiNode(region, toop);
3309   C->set_has_split_ifs(true); // Has chance for split-if optimization
3310 
3311   // Use null-cast information if it is available
3312   bool speculative_not_null = false;
3313   bool never_see_null = ((failure_control == nullptr)  // regular case only
3314                          && seems_never_null(obj, data, speculative_not_null));
3315 
3316   // Null check; get casted pointer; set region slot 3
3317   Node* null_ctl = top();
3318   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3319 
3320   // If not_null_obj is dead, only null-path is taken
3321   if (stopped()) {              // Doing instance-of on a null?
3322     set_control(null_ctl);
3323     return null();
3324   }
3325   region->init_req(_null_path, null_ctl);
3326   phi   ->init_req(_null_path, null());  // Set null path value
3327   if (null_ctl == top()) {
3328     // Do this eagerly, so that pattern matches like is_diamond_phi
3329     // will work even during parsing.
3330     assert(_null_path == PATH_LIMIT-1, "delete last");
3331     region->del_req(_null_path);
3332     phi   ->del_req(_null_path);
3333   }
3334 
3335   Node* cast_obj = nullptr;
3336   if (tk->klass_is_exact()) {
3337     // The following optimization tries to statically cast the speculative type of the object
3338     // (for example obtained during profiling) to the type of the superklass and then do a
3339     // dynamic check that the type of the object is what we expect. To work correctly
3340     // for checkcast and aastore the type of superklass should be exact.
3341     const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3342     // We may not have profiling here or it may not help us. If we have
3343     // a speculative type use it to perform an exact cast.
3344     ciKlass* spec_obj_type = obj_type->speculative_type();
3345     if (spec_obj_type != nullptr || data != nullptr) {
3346       cast_obj = maybe_cast_profiled_receiver(not_null_obj, tk, spec_obj_type, safe_for_replace);
3347       if (cast_obj != nullptr) {
3348         if (failure_control != nullptr) // failure is now impossible
3349           (*failure_control) = top();
3350         // adjust the type of the phi to the exact klass:
3351         phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3352       }
3353     }
3354   }
3355 
3356   if (cast_obj == nullptr) {
3357     // Generate the subtype check
3358     Node* not_subtype_ctrl = gen_subtype_check(not_null_obj, superklass );
3359 
3360     // Plug in success path into the merge
3361     cast_obj = _gvn.transform(new CheckCastPPNode(control(), not_null_obj, toop));
3362     // Failure path ends in uncommon trap (or may be dead - failure impossible)
3363     if (failure_control == nullptr) {
3364       if (not_subtype_ctrl != top()) { // If failure is possible
3365         PreserveJVMState pjvms(this);
3366         set_control(not_subtype_ctrl);
3367         bool is_aastore = (java_bc() == Bytecodes::_aastore);
3368         Deoptimization::DeoptReason reason = is_aastore ?
3369           Deoptimization::Reason_array_check : Deoptimization::Reason_class_check;
3370         builtin_throw(reason);
3371       }
3372     } else {
3373       (*failure_control) = not_subtype_ctrl;
3374     }
3375   }
3376 
3377   region->init_req(_obj_path, control());
3378   phi   ->init_req(_obj_path, cast_obj);
3379 
3380   // A merge of null or Casted-NotNull obj
3381   Node* res = _gvn.transform(phi);
3382 
3383   // Note I do NOT always 'replace_in_map(obj,result)' here.
3384   //  if( tk->klass()->can_be_primary_super()  )
3385     // This means that if I successfully store an Object into an array-of-String
3386     // I 'forget' that the Object is really now known to be a String.  I have to
3387     // do this because we don't have true union types for interfaces - if I store
3388     // a Baz into an array-of-Interface and then tell the optimizer it's an
3389     // Interface, I forget that it's also a Baz and cannot do Baz-like field
3390     // references to it.  FIX THIS WHEN UNION TYPES APPEAR!
3391   //  replace_in_map( obj, res );
3392 
3393   // Return final merged results
3394   set_control( _gvn.transform(region) );
3395   record_for_igvn(region);
3396 
3397   return record_profiled_receiver_for_speculation(res);
3398 }
3399 
3400 //------------------------------next_monitor-----------------------------------
3401 // What number should be given to the next monitor?
3402 int GraphKit::next_monitor() {
3403   int current = jvms()->monitor_depth()* C->sync_stack_slots();
3404   int next = current + C->sync_stack_slots();
3405   // Keep the toplevel high water mark current:
3406   if (C->fixed_slots() < next)  C->set_fixed_slots(next);
3407   return current;
3408 }
3409 
3410 //------------------------------insert_mem_bar---------------------------------
3411 // Memory barrier to avoid floating things around
3412 // The membar serves as a pinch point between both control and all memory slices.
3413 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3414   MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3415   mb->init_req(TypeFunc::Control, control());
3416   mb->init_req(TypeFunc::Memory,  reset_memory());
3417   Node* membar = _gvn.transform(mb);
3418   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3419   set_all_memory_call(membar);
3420   return membar;
3421 }
3422 
3423 //-------------------------insert_mem_bar_volatile----------------------------
3424 // Memory barrier to avoid floating things around
3425 // The membar serves as a pinch point between both control and memory(alias_idx).
3426 // If you want to make a pinch point on all memory slices, do not use this
3427 // function (even with AliasIdxBot); use insert_mem_bar() instead.
3428 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3429   // When Parse::do_put_xxx updates a volatile field, it appends a series
3430   // of MemBarVolatile nodes, one for *each* volatile field alias category.
3431   // The first membar is on the same memory slice as the field store opcode.
3432   // This forces the membar to follow the store.  (Bug 6500685 broke this.)
3433   // All the other membars (for other volatile slices, including AliasIdxBot,
3434   // which stands for all unknown volatile slices) are control-dependent
3435   // on the first membar.  This prevents later volatile loads or stores
3436   // from sliding up past the just-emitted store.
3437 
3438   MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3439   mb->set_req(TypeFunc::Control,control());
3440   if (alias_idx == Compile::AliasIdxBot) {
3441     mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3442   } else {
3443     assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3444     mb->set_req(TypeFunc::Memory, memory(alias_idx));
3445   }
3446   Node* membar = _gvn.transform(mb);
3447   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3448   if (alias_idx == Compile::AliasIdxBot) {
3449     merged_memory()->set_base_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)));
3450   } else {
3451     set_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)),alias_idx);
3452   }
3453   return membar;
3454 }
3455 
3456 //------------------------------shared_lock------------------------------------
3457 // Emit locking code.
3458 FastLockNode* GraphKit::shared_lock(Node* obj) {
3459   // bci is either a monitorenter bc or InvocationEntryBci
3460   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3461   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3462 
3463   if( !GenerateSynchronizationCode )
3464     return nullptr;                // Not locking things?
3465   if (stopped())                // Dead monitor?
3466     return nullptr;
3467 
3468   assert(dead_locals_are_killed(), "should kill locals before sync. point");
3469 
3470   // Box the stack location
3471   Node* box = new BoxLockNode(next_monitor());
3472   // Check for bailout after new BoxLockNode
3473   if (failing()) { return nullptr; }
3474   box = _gvn.transform(box);
3475   Node* mem = reset_memory();
3476 
3477   FastLockNode * flock = _gvn.transform(new FastLockNode(0, obj, box) )->as_FastLock();
3478 
3479   // Create the rtm counters for this fast lock if needed.
3480   flock->create_rtm_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3481 
3482   // Add monitor to debug info for the slow path.  If we block inside the
3483   // slow path and de-opt, we need the monitor hanging around
3484   map()->push_monitor( flock );
3485 
3486   const TypeFunc *tf = LockNode::lock_type();
3487   LockNode *lock = new LockNode(C, tf);
3488 
3489   lock->init_req( TypeFunc::Control, control() );
3490   lock->init_req( TypeFunc::Memory , mem );
3491   lock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
3492   lock->init_req( TypeFunc::FramePtr, frameptr() );
3493   lock->init_req( TypeFunc::ReturnAdr, top() );
3494 
3495   lock->init_req(TypeFunc::Parms + 0, obj);
3496   lock->init_req(TypeFunc::Parms + 1, box);
3497   lock->init_req(TypeFunc::Parms + 2, flock);
3498   add_safepoint_edges(lock);
3499 
3500   lock = _gvn.transform( lock )->as_Lock();
3501 
3502   // lock has no side-effects, sets few values
3503   set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3504 
3505   insert_mem_bar(Op_MemBarAcquireLock);
3506 
3507   // Add this to the worklist so that the lock can be eliminated
3508   record_for_igvn(lock);
3509 
3510 #ifndef PRODUCT
3511   if (PrintLockStatistics) {
3512     // Update the counter for this lock.  Don't bother using an atomic
3513     // operation since we don't require absolute accuracy.
3514     lock->create_lock_counter(map()->jvms());
3515     increment_counter(lock->counter()->addr());
3516   }
3517 #endif
3518 
3519   return flock;
3520 }
3521 
3522 
3523 //------------------------------shared_unlock----------------------------------
3524 // Emit unlocking code.
3525 void GraphKit::shared_unlock(Node* box, Node* obj) {
3526   // bci is either a monitorenter bc or InvocationEntryBci
3527   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3528   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3529 
3530   if( !GenerateSynchronizationCode )
3531     return;
3532   if (stopped()) {               // Dead monitor?
3533     map()->pop_monitor();        // Kill monitor from debug info
3534     return;
3535   }
3536 
3537   // Memory barrier to avoid floating things down past the locked region
3538   insert_mem_bar(Op_MemBarReleaseLock);
3539 
3540   const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3541   UnlockNode *unlock = new UnlockNode(C, tf);
3542 #ifdef ASSERT
3543   unlock->set_dbg_jvms(sync_jvms());
3544 #endif
3545   uint raw_idx = Compile::AliasIdxRaw;
3546   unlock->init_req( TypeFunc::Control, control() );
3547   unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3548   unlock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
3549   unlock->init_req( TypeFunc::FramePtr, frameptr() );
3550   unlock->init_req( TypeFunc::ReturnAdr, top() );
3551 
3552   unlock->init_req(TypeFunc::Parms + 0, obj);
3553   unlock->init_req(TypeFunc::Parms + 1, box);
3554   unlock = _gvn.transform(unlock)->as_Unlock();
3555 
3556   Node* mem = reset_memory();
3557 
3558   // unlock has no side-effects, sets few values
3559   set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3560 
3561   // Kill monitor from debug info
3562   map()->pop_monitor( );
3563 }
3564 
3565 //-------------------------------get_layout_helper-----------------------------
3566 // If the given klass is a constant or known to be an array,
3567 // fetch the constant layout helper value into constant_value
3568 // and return null.  Otherwise, load the non-constant
3569 // layout helper value, and return the node which represents it.
3570 // This two-faced routine is useful because allocation sites
3571 // almost always feature constant types.
3572 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3573   const TypeKlassPtr* klass_t = _gvn.type(klass_node)->isa_klassptr();
3574   if (!StressReflectiveCode && klass_t != nullptr) {
3575     bool xklass = klass_t->klass_is_exact();
3576     if (xklass || (klass_t->isa_aryklassptr() && klass_t->is_aryklassptr()->elem() != Type::BOTTOM)) {
3577       jint lhelper;
3578       if (klass_t->isa_aryklassptr()) {
3579         BasicType elem = klass_t->as_instance_type()->isa_aryptr()->elem()->array_element_basic_type();
3580         if (is_reference_type(elem, true)) {
3581           elem = T_OBJECT;
3582         }
3583         lhelper = Klass::array_layout_helper(elem);
3584       } else {
3585         lhelper = klass_t->is_instklassptr()->exact_klass()->layout_helper();
3586       }
3587       if (lhelper != Klass::_lh_neutral_value) {
3588         constant_value = lhelper;
3589         return (Node*) nullptr;
3590       }
3591     }
3592   }
3593   constant_value = Klass::_lh_neutral_value;  // put in a known value
3594   Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
3595   return make_load(nullptr, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3596 }
3597 
3598 // We just put in an allocate/initialize with a big raw-memory effect.
3599 // Hook selected additional alias categories on the initialization.
3600 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3601                                 MergeMemNode* init_in_merge,
3602                                 Node* init_out_raw) {
3603   DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3604   assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3605 
3606   Node* prevmem = kit.memory(alias_idx);
3607   init_in_merge->set_memory_at(alias_idx, prevmem);
3608   kit.set_memory(init_out_raw, alias_idx);
3609 }
3610 
3611 //---------------------------set_output_for_allocation-------------------------
3612 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3613                                           const TypeOopPtr* oop_type,
3614                                           bool deoptimize_on_exception) {
3615   int rawidx = Compile::AliasIdxRaw;
3616   alloc->set_req( TypeFunc::FramePtr, frameptr() );
3617   add_safepoint_edges(alloc);
3618   Node* allocx = _gvn.transform(alloc);
3619   set_control( _gvn.transform(new ProjNode(allocx, TypeFunc::Control) ) );
3620   // create memory projection for i_o
3621   set_memory ( _gvn.transform( new ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3622   make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception);
3623 
3624   // create a memory projection as for the normal control path
3625   Node* malloc = _gvn.transform(new ProjNode(allocx, TypeFunc::Memory));
3626   set_memory(malloc, rawidx);
3627 
3628   // a normal slow-call doesn't change i_o, but an allocation does
3629   // we create a separate i_o projection for the normal control path
3630   set_i_o(_gvn.transform( new ProjNode(allocx, TypeFunc::I_O, false) ) );
3631   Node* rawoop = _gvn.transform( new ProjNode(allocx, TypeFunc::Parms) );
3632 
3633   // put in an initialization barrier
3634   InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3635                                                  rawoop)->as_Initialize();
3636   assert(alloc->initialization() == init,  "2-way macro link must work");
3637   assert(init ->allocation()     == alloc, "2-way macro link must work");
3638   {
3639     // Extract memory strands which may participate in the new object's
3640     // initialization, and source them from the new InitializeNode.
3641     // This will allow us to observe initializations when they occur,
3642     // and link them properly (as a group) to the InitializeNode.
3643     assert(init->in(InitializeNode::Memory) == malloc, "");
3644     MergeMemNode* minit_in = MergeMemNode::make(malloc);
3645     init->set_req(InitializeNode::Memory, minit_in);
3646     record_for_igvn(minit_in); // fold it up later, if possible
3647     Node* minit_out = memory(rawidx);
3648     assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3649     // Add an edge in the MergeMem for the header fields so an access
3650     // to one of those has correct memory state
3651     set_memory(minit_out, C->get_alias_index(oop_type->add_offset(oopDesc::mark_offset_in_bytes())));
3652     set_memory(minit_out, C->get_alias_index(oop_type->add_offset(oopDesc::klass_offset_in_bytes())));
3653     if (oop_type->isa_aryptr()) {
3654       const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3655       int            elemidx  = C->get_alias_index(telemref);
3656       hook_memory_on_init(*this, elemidx, minit_in, minit_out);
3657     } else if (oop_type->isa_instptr()) {
3658       ciInstanceKlass* ik = oop_type->is_instptr()->instance_klass();
3659       for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3660         ciField* field = ik->nonstatic_field_at(i);
3661         if (field->offset_in_bytes() >= TrackedInitializationLimit * HeapWordSize)
3662           continue;  // do not bother to track really large numbers of fields
3663         // Find (or create) the alias category for this field:
3664         int fieldidx = C->alias_type(field)->index();
3665         hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3666       }
3667     }
3668   }
3669 
3670   // Cast raw oop to the real thing...
3671   Node* javaoop = new CheckCastPPNode(control(), rawoop, oop_type);
3672   javaoop = _gvn.transform(javaoop);
3673   C->set_recent_alloc(control(), javaoop);
3674   assert(just_allocated_object(control()) == javaoop, "just allocated");
3675 
3676 #ifdef ASSERT
3677   { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3678     assert(AllocateNode::Ideal_allocation(rawoop) == alloc,
3679            "Ideal_allocation works");
3680     assert(AllocateNode::Ideal_allocation(javaoop) == alloc,
3681            "Ideal_allocation works");
3682     if (alloc->is_AllocateArray()) {
3683       assert(AllocateArrayNode::Ideal_array_allocation(rawoop) == alloc->as_AllocateArray(),
3684              "Ideal_allocation works");
3685       assert(AllocateArrayNode::Ideal_array_allocation(javaoop) == alloc->as_AllocateArray(),
3686              "Ideal_allocation works");
3687     } else {
3688       assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3689     }
3690   }
3691 #endif //ASSERT
3692 
3693   return javaoop;
3694 }
3695 
3696 //---------------------------new_instance--------------------------------------
3697 // This routine takes a klass_node which may be constant (for a static type)
3698 // or may be non-constant (for reflective code).  It will work equally well
3699 // for either, and the graph will fold nicely if the optimizer later reduces
3700 // the type to a constant.
3701 // The optional arguments are for specialized use by intrinsics:
3702 //  - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3703 //  - If 'return_size_val', report the total object size to the caller.
3704 //  - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3705 Node* GraphKit::new_instance(Node* klass_node,
3706                              Node* extra_slow_test,
3707                              Node* *return_size_val,
3708                              bool deoptimize_on_exception) {
3709   // Compute size in doublewords
3710   // The size is always an integral number of doublewords, represented
3711   // as a positive bytewise size stored in the klass's layout_helper.
3712   // The layout_helper also encodes (in a low bit) the need for a slow path.
3713   jint  layout_con = Klass::_lh_neutral_value;
3714   Node* layout_val = get_layout_helper(klass_node, layout_con);
3715   int   layout_is_con = (layout_val == nullptr);
3716 
3717   if (extra_slow_test == nullptr)  extra_slow_test = intcon(0);
3718   // Generate the initial go-slow test.  It's either ALWAYS (return a
3719   // Node for 1) or NEVER (return a null) or perhaps (in the reflective
3720   // case) a computed value derived from the layout_helper.
3721   Node* initial_slow_test = nullptr;
3722   if (layout_is_con) {
3723     assert(!StressReflectiveCode, "stress mode does not use these paths");
3724     bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3725     initial_slow_test = must_go_slow ? intcon(1) : extra_slow_test;
3726   } else {   // reflective case
3727     // This reflective path is used by Unsafe.allocateInstance.
3728     // (It may be stress-tested by specifying StressReflectiveCode.)
3729     // Basically, we want to get into the VM is there's an illegal argument.
3730     Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3731     initial_slow_test = _gvn.transform( new AndINode(layout_val, bit) );
3732     if (extra_slow_test != intcon(0)) {
3733       initial_slow_test = _gvn.transform( new OrINode(initial_slow_test, extra_slow_test) );
3734     }
3735     // (Macro-expander will further convert this to a Bool, if necessary.)
3736   }
3737 
3738   // Find the size in bytes.  This is easy; it's the layout_helper.
3739   // The size value must be valid even if the slow path is taken.
3740   Node* size = nullptr;
3741   if (layout_is_con) {
3742     size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3743   } else {   // reflective case
3744     // This reflective path is used by clone and Unsafe.allocateInstance.
3745     size = ConvI2X(layout_val);
3746 
3747     // Clear the low bits to extract layout_helper_size_in_bytes:
3748     assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3749     Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3750     size = _gvn.transform( new AndXNode(size, mask) );
3751   }
3752   if (return_size_val != nullptr) {
3753     (*return_size_val) = size;
3754   }
3755 
3756   // This is a precise notnull oop of the klass.
3757   // (Actually, it need not be precise if this is a reflective allocation.)
3758   // It's what we cast the result to.
3759   const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3760   if (!tklass)  tklass = TypeInstKlassPtr::OBJECT;
3761   const TypeOopPtr* oop_type = tklass->as_instance_type();
3762 
3763   // Now generate allocation code
3764 
3765   // The entire memory state is needed for slow path of the allocation
3766   // since GC and deoptimization can happened.
3767   Node *mem = reset_memory();
3768   set_all_memory(mem); // Create new memory state
3769 
3770   AllocateNode* alloc = new AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3771                                          control(), mem, i_o(),
3772                                          size, klass_node,
3773                                          initial_slow_test);
3774 
3775   return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception);
3776 }
3777 
3778 //-------------------------------new_array-------------------------------------
3779 // helper for both newarray and anewarray
3780 // The 'length' parameter is (obviously) the length of the array.
3781 // The optional arguments are for specialized use by intrinsics:
3782 //  - If 'return_size_val', report the non-padded array size (sum of header size
3783 //    and array body) to the caller.
3784 //  - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3785 Node* GraphKit::new_array(Node* klass_node,     // array klass (maybe variable)
3786                           Node* length,         // number of array elements
3787                           int   nargs,          // number of arguments to push back for uncommon trap
3788                           Node* *return_size_val,
3789                           bool deoptimize_on_exception) {
3790   jint  layout_con = Klass::_lh_neutral_value;
3791   Node* layout_val = get_layout_helper(klass_node, layout_con);
3792   int   layout_is_con = (layout_val == nullptr);
3793 
3794   if (!layout_is_con && !StressReflectiveCode &&
3795       !too_many_traps(Deoptimization::Reason_class_check)) {
3796     // This is a reflective array creation site.
3797     // Optimistically assume that it is a subtype of Object[],
3798     // so that we can fold up all the address arithmetic.
3799     layout_con = Klass::array_layout_helper(T_OBJECT);
3800     Node* cmp_lh = _gvn.transform( new CmpINode(layout_val, intcon(layout_con)) );
3801     Node* bol_lh = _gvn.transform( new BoolNode(cmp_lh, BoolTest::eq) );
3802     { BuildCutout unless(this, bol_lh, PROB_MAX);
3803       inc_sp(nargs);
3804       uncommon_trap(Deoptimization::Reason_class_check,
3805                     Deoptimization::Action_maybe_recompile);
3806     }
3807     layout_val = nullptr;
3808     layout_is_con = true;
3809   }
3810 
3811   // Generate the initial go-slow test.  Make sure we do not overflow
3812   // if length is huge (near 2Gig) or negative!  We do not need
3813   // exact double-words here, just a close approximation of needed
3814   // double-words.  We can't add any offset or rounding bits, lest we
3815   // take a size -1 of bytes and make it positive.  Use an unsigned
3816   // compare, so negative sizes look hugely positive.
3817   int fast_size_limit = FastAllocateSizeLimit;
3818   if (layout_is_con) {
3819     assert(!StressReflectiveCode, "stress mode does not use these paths");
3820     // Increase the size limit if we have exact knowledge of array type.
3821     int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3822     fast_size_limit <<= (LogBytesPerLong - log2_esize);
3823   }
3824 
3825   Node* initial_slow_cmp  = _gvn.transform( new CmpUNode( length, intcon( fast_size_limit ) ) );
3826   Node* initial_slow_test = _gvn.transform( new BoolNode( initial_slow_cmp, BoolTest::gt ) );
3827 
3828   // --- Size Computation ---
3829   // array_size = round_to_heap(array_header + (length << elem_shift));
3830   // where round_to_heap(x) == align_to(x, MinObjAlignmentInBytes)
3831   // and align_to(x, y) == ((x + y-1) & ~(y-1))
3832   // The rounding mask is strength-reduced, if possible.
3833   int round_mask = MinObjAlignmentInBytes - 1;
3834   Node* header_size = nullptr;
3835   // (T_BYTE has the weakest alignment and size restrictions...)
3836   if (layout_is_con) {
3837     int       hsize  = Klass::layout_helper_header_size(layout_con);
3838     int       eshift = Klass::layout_helper_log2_element_size(layout_con);
3839     if ((round_mask & ~right_n_bits(eshift)) == 0)
3840       round_mask = 0;  // strength-reduce it if it goes away completely
3841     assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3842     int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3843     assert(header_size_min <= hsize, "generic minimum is smallest");
3844     header_size = intcon(hsize);
3845   } else {
3846     Node* hss   = intcon(Klass::_lh_header_size_shift);
3847     Node* hsm   = intcon(Klass::_lh_header_size_mask);
3848     header_size = _gvn.transform(new URShiftINode(layout_val, hss));
3849     header_size = _gvn.transform(new AndINode(header_size, hsm));
3850   }
3851 
3852   Node* elem_shift = nullptr;
3853   if (layout_is_con) {
3854     int eshift = Klass::layout_helper_log2_element_size(layout_con);
3855     if (eshift != 0)
3856       elem_shift = intcon(eshift);
3857   } else {
3858     // There is no need to mask or shift this value.
3859     // The semantics of LShiftINode include an implicit mask to 0x1F.
3860     assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3861     elem_shift = layout_val;
3862   }
3863 
3864   // Transition to native address size for all offset calculations:
3865   Node* lengthx = ConvI2X(length);
3866   Node* headerx = ConvI2X(header_size);
3867 #ifdef _LP64
3868   { const TypeInt* tilen = _gvn.find_int_type(length);
3869     if (tilen != nullptr && tilen->_lo < 0) {
3870       // Add a manual constraint to a positive range.  Cf. array_element_address.
3871       jint size_max = fast_size_limit;
3872       if (size_max > tilen->_hi)  size_max = tilen->_hi;
3873       const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin);
3874 
3875       // Only do a narrow I2L conversion if the range check passed.
3876       IfNode* iff = new IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
3877       _gvn.transform(iff);
3878       RegionNode* region = new RegionNode(3);
3879       _gvn.set_type(region, Type::CONTROL);
3880       lengthx = new PhiNode(region, TypeLong::LONG);
3881       _gvn.set_type(lengthx, TypeLong::LONG);
3882 
3883       // Range check passed. Use ConvI2L node with narrow type.
3884       Node* passed = IfFalse(iff);
3885       region->init_req(1, passed);
3886       // Make I2L conversion control dependent to prevent it from
3887       // floating above the range check during loop optimizations.
3888       lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed));
3889 
3890       // Range check failed. Use ConvI2L with wide type because length may be invalid.
3891       region->init_req(2, IfTrue(iff));
3892       lengthx->init_req(2, ConvI2X(length));
3893 
3894       set_control(region);
3895       record_for_igvn(region);
3896       record_for_igvn(lengthx);
3897     }
3898   }
3899 #endif
3900 
3901   // Combine header size and body size for the array copy part, then align (if
3902   // necessary) for the allocation part. This computation cannot overflow,
3903   // because it is used only in two places, one where the length is sharply
3904   // limited, and the other after a successful allocation.
3905   Node* abody = lengthx;
3906   if (elem_shift != nullptr) {
3907     abody = _gvn.transform(new LShiftXNode(lengthx, elem_shift));
3908   }
3909   Node* non_rounded_size = _gvn.transform(new AddXNode(headerx, abody));
3910 
3911   if (return_size_val != nullptr) {
3912     // This is the size
3913     (*return_size_val) = non_rounded_size;
3914   }
3915 
3916   Node* size = non_rounded_size;
3917   if (round_mask != 0) {
3918     Node* mask1 = MakeConX(round_mask);
3919     size = _gvn.transform(new AddXNode(size, mask1));
3920     Node* mask2 = MakeConX(~round_mask);
3921     size = _gvn.transform(new AndXNode(size, mask2));
3922   }
3923   // else if round_mask == 0, the size computation is self-rounding
3924 
3925   // Now generate allocation code
3926 
3927   // The entire memory state is needed for slow path of the allocation
3928   // since GC and deoptimization can happened.
3929   Node *mem = reset_memory();
3930   set_all_memory(mem); // Create new memory state
3931 
3932   if (initial_slow_test->is_Bool()) {
3933     // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3934     initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3935   }
3936 
3937   const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3938   Node* valid_length_test = _gvn.intcon(1);
3939   if (ary_type->isa_aryptr()) {
3940     BasicType bt = ary_type->isa_aryptr()->elem()->array_element_basic_type();
3941     jint max = TypeAryPtr::max_array_length(bt);
3942     Node* valid_length_cmp  = _gvn.transform(new CmpUNode(length, intcon(max)));
3943     valid_length_test = _gvn.transform(new BoolNode(valid_length_cmp, BoolTest::le));
3944   }
3945 
3946   // Create the AllocateArrayNode and its result projections
3947   AllocateArrayNode* alloc
3948     = new AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
3949                             control(), mem, i_o(),
3950                             size, klass_node,
3951                             initial_slow_test,
3952                             length, valid_length_test);
3953 
3954   // Cast to correct type.  Note that the klass_node may be constant or not,
3955   // and in the latter case the actual array type will be inexact also.
3956   // (This happens via a non-constant argument to inline_native_newArray.)
3957   // In any case, the value of klass_node provides the desired array type.
3958   const TypeInt* length_type = _gvn.find_int_type(length);
3959   if (ary_type->isa_aryptr() && length_type != nullptr) {
3960     // Try to get a better type than POS for the size
3961     ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3962   }
3963 
3964   Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception);
3965 
3966   array_ideal_length(alloc, ary_type, true);
3967   return javaoop;
3968 }
3969 
3970 // The following "Ideal_foo" functions are placed here because they recognize
3971 // the graph shapes created by the functions immediately above.
3972 
3973 //---------------------------Ideal_allocation----------------------------------
3974 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3975 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr) {
3976   if (ptr == nullptr) {     // reduce dumb test in callers
3977     return nullptr;
3978   }
3979 
3980   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
3981   ptr = bs->step_over_gc_barrier(ptr);
3982 
3983   if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
3984     ptr = ptr->in(1);
3985     if (ptr == nullptr) return nullptr;
3986   }
3987   // Return null for allocations with several casts:
3988   //   j.l.reflect.Array.newInstance(jobject, jint)
3989   //   Object.clone()
3990   // to keep more precise type from last cast.
3991   if (ptr->is_Proj()) {
3992     Node* allo = ptr->in(0);
3993     if (allo != nullptr && allo->is_Allocate()) {
3994       return allo->as_Allocate();
3995     }
3996   }
3997   // Report failure to match.
3998   return nullptr;
3999 }
4000 
4001 // Fancy version which also strips off an offset (and reports it to caller).
4002 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseValues* phase,
4003                                              intptr_t& offset) {
4004   Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
4005   if (base == nullptr)  return nullptr;
4006   return Ideal_allocation(base);
4007 }
4008 
4009 // Trace Initialize <- Proj[Parm] <- Allocate
4010 AllocateNode* InitializeNode::allocation() {
4011   Node* rawoop = in(InitializeNode::RawAddress);
4012   if (rawoop->is_Proj()) {
4013     Node* alloc = rawoop->in(0);
4014     if (alloc->is_Allocate()) {
4015       return alloc->as_Allocate();
4016     }
4017   }
4018   return nullptr;
4019 }
4020 
4021 // Trace Allocate -> Proj[Parm] -> Initialize
4022 InitializeNode* AllocateNode::initialization() {
4023   ProjNode* rawoop = proj_out_or_null(AllocateNode::RawAddress);
4024   if (rawoop == nullptr)  return nullptr;
4025   for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
4026     Node* init = rawoop->fast_out(i);
4027     if (init->is_Initialize()) {
4028       assert(init->as_Initialize()->allocation() == this, "2-way link");
4029       return init->as_Initialize();
4030     }
4031   }
4032   return nullptr;
4033 }
4034 
4035 // Add a Parse Predicate with an uncommon trap on the failing/false path. Normal control will continue on the true path.
4036 void GraphKit::add_parse_predicate(Deoptimization::DeoptReason reason, const int nargs) {
4037   // Too many traps seen?
4038   if (too_many_traps(reason)) {
4039 #ifdef ASSERT
4040     if (TraceLoopPredicate) {
4041       int tc = C->trap_count(reason);
4042       tty->print("too many traps=%s tcount=%d in ",
4043                     Deoptimization::trap_reason_name(reason), tc);
4044       method()->print(); // which method has too many predicate traps
4045       tty->cr();
4046     }
4047 #endif
4048     // We cannot afford to take more traps here,
4049     // do not generate Parse Predicate.
4050     return;
4051   }
4052 
4053   ParsePredicateNode* parse_predicate = new ParsePredicateNode(control(), reason, &_gvn);
4054   _gvn.set_type(parse_predicate, parse_predicate->Value(&_gvn));
4055   Node* if_false = _gvn.transform(new IfFalseNode(parse_predicate));
4056   {
4057     PreserveJVMState pjvms(this);
4058     set_control(if_false);
4059     inc_sp(nargs);
4060     uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
4061   }
4062   Node* if_true = _gvn.transform(new IfTrueNode(parse_predicate));
4063   set_control(if_true);
4064 }
4065 
4066 // Add Parse Predicates which serve as placeholders to create new Runtime Predicates above them. All
4067 // Runtime Predicates inside a Runtime Predicate block share the same uncommon trap as the Parse Predicate.
4068 void GraphKit::add_parse_predicates(int nargs) {
4069   if (UseLoopPredicate) {
4070     add_parse_predicate(Deoptimization::Reason_predicate, nargs);
4071   }
4072   if (UseProfiledLoopPredicate) {
4073     add_parse_predicate(Deoptimization::Reason_profile_predicate, nargs);
4074   }
4075   // Loop Limit Check Predicate should be near the loop.
4076   add_parse_predicate(Deoptimization::Reason_loop_limit_check, nargs);
4077 }
4078 
4079 void GraphKit::sync_kit(IdealKit& ideal) {
4080   set_all_memory(ideal.merged_memory());
4081   set_i_o(ideal.i_o());
4082   set_control(ideal.ctrl());
4083 }
4084 
4085 void GraphKit::final_sync(IdealKit& ideal) {
4086   // Final sync IdealKit and graphKit.
4087   sync_kit(ideal);
4088 }
4089 
4090 Node* GraphKit::load_String_length(Node* str, bool set_ctrl) {
4091   Node* len = load_array_length(load_String_value(str, set_ctrl));
4092   Node* coder = load_String_coder(str, set_ctrl);
4093   // Divide length by 2 if coder is UTF16
4094   return _gvn.transform(new RShiftINode(len, coder));
4095 }
4096 
4097 Node* GraphKit::load_String_value(Node* str, bool set_ctrl) {
4098   int value_offset = java_lang_String::value_offset();
4099   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4100                                                      false, nullptr, 0);
4101   const TypePtr* value_field_type = string_type->add_offset(value_offset);
4102   const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
4103                                                   TypeAry::make(TypeInt::BYTE, TypeInt::POS),
4104                                                   ciTypeArrayKlass::make(T_BYTE), true, 0);
4105   Node* p = basic_plus_adr(str, str, value_offset);
4106   Node* load = access_load_at(str, p, value_field_type, value_type, T_OBJECT,
4107                               IN_HEAP | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0) | MO_UNORDERED);
4108   return load;
4109 }
4110 
4111 Node* GraphKit::load_String_coder(Node* str, bool set_ctrl) {
4112   if (!CompactStrings) {
4113     return intcon(java_lang_String::CODER_UTF16);
4114   }
4115   int coder_offset = java_lang_String::coder_offset();
4116   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4117                                                      false, nullptr, 0);
4118   const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4119 
4120   Node* p = basic_plus_adr(str, str, coder_offset);
4121   Node* load = access_load_at(str, p, coder_field_type, TypeInt::BYTE, T_BYTE,
4122                               IN_HEAP | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0) | MO_UNORDERED);
4123   return load;
4124 }
4125 
4126 void GraphKit::store_String_value(Node* str, Node* value) {
4127   int value_offset = java_lang_String::value_offset();
4128   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4129                                                      false, nullptr, 0);
4130   const TypePtr* value_field_type = string_type->add_offset(value_offset);
4131 
4132   access_store_at(str,  basic_plus_adr(str, value_offset), value_field_type,
4133                   value, TypeAryPtr::BYTES, T_OBJECT, IN_HEAP | MO_UNORDERED);
4134 }
4135 
4136 void GraphKit::store_String_coder(Node* str, Node* value) {
4137   int coder_offset = java_lang_String::coder_offset();
4138   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4139                                                      false, nullptr, 0);
4140   const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4141 
4142   access_store_at(str, basic_plus_adr(str, coder_offset), coder_field_type,
4143                   value, TypeInt::BYTE, T_BYTE, IN_HEAP | MO_UNORDERED);
4144 }
4145 
4146 // Capture src and dst memory state with a MergeMemNode
4147 Node* GraphKit::capture_memory(const TypePtr* src_type, const TypePtr* dst_type) {
4148   if (src_type == dst_type) {
4149     // Types are equal, we don't need a MergeMemNode
4150     return memory(src_type);
4151   }
4152   MergeMemNode* merge = MergeMemNode::make(map()->memory());
4153   record_for_igvn(merge); // fold it up later, if possible
4154   int src_idx = C->get_alias_index(src_type);
4155   int dst_idx = C->get_alias_index(dst_type);
4156   merge->set_memory_at(src_idx, memory(src_idx));
4157   merge->set_memory_at(dst_idx, memory(dst_idx));
4158   return merge;
4159 }
4160 
4161 Node* GraphKit::compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count) {
4162   assert(Matcher::match_rule_supported(Op_StrCompressedCopy), "Intrinsic not supported");
4163   assert(src_type == TypeAryPtr::BYTES || src_type == TypeAryPtr::CHARS, "invalid source type");
4164   // If input and output memory types differ, capture both states to preserve
4165   // the dependency between preceding and subsequent loads/stores.
4166   // For example, the following program:
4167   //  StoreB
4168   //  compress_string
4169   //  LoadB
4170   // has this memory graph (use->def):
4171   //  LoadB -> compress_string -> CharMem
4172   //             ... -> StoreB -> ByteMem
4173   // The intrinsic hides the dependency between LoadB and StoreB, causing
4174   // the load to read from memory not containing the result of the StoreB.
4175   // The correct memory graph should look like this:
4176   //  LoadB -> compress_string -> MergeMem(CharMem, StoreB(ByteMem))
4177   Node* mem = capture_memory(src_type, TypeAryPtr::BYTES);
4178   StrCompressedCopyNode* str = new StrCompressedCopyNode(control(), mem, src, dst, count);
4179   Node* res_mem = _gvn.transform(new SCMemProjNode(_gvn.transform(str)));
4180   set_memory(res_mem, TypeAryPtr::BYTES);
4181   return str;
4182 }
4183 
4184 void GraphKit::inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count) {
4185   assert(Matcher::match_rule_supported(Op_StrInflatedCopy), "Intrinsic not supported");
4186   assert(dst_type == TypeAryPtr::BYTES || dst_type == TypeAryPtr::CHARS, "invalid dest type");
4187   // Capture src and dst memory (see comment in 'compress_string').
4188   Node* mem = capture_memory(TypeAryPtr::BYTES, dst_type);
4189   StrInflatedCopyNode* str = new StrInflatedCopyNode(control(), mem, src, dst, count);
4190   set_memory(_gvn.transform(str), dst_type);
4191 }
4192 
4193 void GraphKit::inflate_string_slow(Node* src, Node* dst, Node* start, Node* count) {
4194   /**
4195    * int i_char = start;
4196    * for (int i_byte = 0; i_byte < count; i_byte++) {
4197    *   dst[i_char++] = (char)(src[i_byte] & 0xff);
4198    * }
4199    */
4200   add_parse_predicates();
4201   C->set_has_loops(true);
4202 
4203   RegionNode* head = new RegionNode(3);
4204   head->init_req(1, control());
4205   gvn().set_type(head, Type::CONTROL);
4206   record_for_igvn(head);
4207 
4208   Node* i_byte = new PhiNode(head, TypeInt::INT);
4209   i_byte->init_req(1, intcon(0));
4210   gvn().set_type(i_byte, TypeInt::INT);
4211   record_for_igvn(i_byte);
4212 
4213   Node* i_char = new PhiNode(head, TypeInt::INT);
4214   i_char->init_req(1, start);
4215   gvn().set_type(i_char, TypeInt::INT);
4216   record_for_igvn(i_char);
4217 
4218   Node* mem = PhiNode::make(head, memory(TypeAryPtr::BYTES), Type::MEMORY, TypeAryPtr::BYTES);
4219   gvn().set_type(mem, Type::MEMORY);
4220   record_for_igvn(mem);
4221   set_control(head);
4222   set_memory(mem, TypeAryPtr::BYTES);
4223   Node* ch = load_array_element(src, i_byte, TypeAryPtr::BYTES, /* set_ctrl */ true);
4224   Node* st = store_to_memory(control(), array_element_address(dst, i_char, T_BYTE),
4225                              AndI(ch, intcon(0xff)), T_CHAR, TypeAryPtr::BYTES, MemNode::unordered,
4226                              false, false, true /* mismatched */);
4227 
4228   IfNode* iff = create_and_map_if(head, Bool(CmpI(i_byte, count), BoolTest::lt), PROB_FAIR, COUNT_UNKNOWN);
4229   head->init_req(2, IfTrue(iff));
4230   mem->init_req(2, st);
4231   i_byte->init_req(2, AddI(i_byte, intcon(1)));
4232   i_char->init_req(2, AddI(i_char, intcon(2)));
4233 
4234   set_control(IfFalse(iff));
4235   set_memory(st, TypeAryPtr::BYTES);
4236 }
4237 
4238 Node* GraphKit::make_constant_from_field(ciField* field, Node* obj) {
4239   if (!field->is_constant()) {
4240     return nullptr; // Field not marked as constant.
4241   }
4242   ciInstance* holder = nullptr;
4243   if (!field->is_static()) {
4244     ciObject* const_oop = obj->bottom_type()->is_oopptr()->const_oop();
4245     if (const_oop != nullptr && const_oop->is_instance()) {
4246       holder = const_oop->as_instance();
4247     }
4248   }
4249   const Type* con_type = Type::make_constant_from_field(field, holder, field->layout_type(),
4250                                                         /*is_unsigned_load=*/false);
4251   if (con_type != nullptr) {
4252     return makecon(con_type);
4253   }
4254   return nullptr;
4255 }