1 /*
   2  * Copyright (c) 2001, 2026, 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 "asm/register.hpp"
  26 #include "ci/ciObjArray.hpp"
  27 #include "ci/ciUtilities.hpp"
  28 #include "classfile/javaClasses.hpp"
  29 #include "compiler/compileLog.hpp"
  30 #include "gc/shared/barrierSet.hpp"
  31 #include "gc/shared/c2/barrierSetC2.hpp"
  32 #include "interpreter/interpreter.hpp"
  33 #include "memory/resourceArea.hpp"
  34 #include "oops/trainingData.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/growableArray.hpp"
  52 #include "utilities/powerOfTwo.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_internal()) {
 344     return;  // dying anyway...
 345   }
 346   JVMState* ex_jvms = ex_map->_jvms;
 347   assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
 348   assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
 349   assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
 350   assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
 351   assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects");
 352   assert(ex_map->req() == phi_map->req(), "matching maps");
 353   uint tos = ex_jvms->stkoff() + ex_jvms->sp();
 354   Node*         hidden_merge_mark = root();
 355   Node*         region  = phi_map->control();
 356   MergeMemNode* phi_mem = phi_map->merged_memory();
 357   MergeMemNode* ex_mem  = ex_map->merged_memory();
 358   if (region->in(0) != hidden_merge_mark) {
 359     // The control input is not (yet) a specially-marked region in phi_map.
 360     // Make it so, and build some phis.
 361     region = new RegionNode(2);
 362     _gvn.set_type(region, Type::CONTROL);
 363     region->set_req(0, hidden_merge_mark);  // marks an internal ex-state
 364     region->init_req(1, phi_map->control());
 365     phi_map->set_control(region);
 366     Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
 367     record_for_igvn(io_phi);
 368     _gvn.set_type(io_phi, Type::ABIO);
 369     phi_map->set_i_o(io_phi);
 370     for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
 371       Node* m = mms.memory();
 372       Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
 373       record_for_igvn(m_phi);
 374       _gvn.set_type(m_phi, Type::MEMORY);
 375       mms.set_memory(m_phi);
 376     }
 377   }
 378 
 379   // Either or both of phi_map and ex_map might already be converted into phis.
 380   Node* ex_control = ex_map->control();
 381   // if there is special marking on ex_map also, we add multiple edges from src
 382   bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
 383   // how wide was the destination phi_map, originally?
 384   uint orig_width = region->req();
 385 
 386   if (add_multiple) {
 387     add_n_reqs(region, ex_control);
 388     add_n_reqs(phi_map->i_o(), ex_map->i_o());
 389   } else {
 390     // ex_map has no merges, so we just add single edges everywhere
 391     add_one_req(region, ex_control);
 392     add_one_req(phi_map->i_o(), ex_map->i_o());
 393   }
 394   for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
 395     if (mms.is_empty()) {
 396       // get a copy of the base memory, and patch some inputs into it
 397       const TypePtr* adr_type = mms.adr_type(C);
 398       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
 399       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
 400       mms.set_memory(phi);
 401       // Prepare to append interesting stuff onto the newly sliced phi:
 402       while (phi->req() > orig_width)  phi->del_req(phi->req()-1);
 403     }
 404     // Append stuff from ex_map:
 405     if (add_multiple) {
 406       add_n_reqs(mms.memory(), mms.memory2());
 407     } else {
 408       add_one_req(mms.memory(), mms.memory2());
 409     }
 410   }
 411   uint limit = ex_map->req();
 412   for (uint i = TypeFunc::Parms; i < limit; i++) {
 413     // Skip everything in the JVMS after tos.  (The ex_oop follows.)
 414     if (i == tos)  i = ex_jvms->monoff();
 415     Node* src = ex_map->in(i);
 416     Node* dst = phi_map->in(i);
 417     if (src != dst) {
 418       PhiNode* phi;
 419       if (dst->in(0) != region) {
 420         dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
 421         record_for_igvn(phi);
 422         _gvn.set_type(phi, phi->type());
 423         phi_map->set_req(i, dst);
 424         // Prepare to append interesting stuff onto the new phi:
 425         while (dst->req() > orig_width)  dst->del_req(dst->req()-1);
 426       } else {
 427         assert(dst->is_Phi(), "nobody else uses a hidden region");
 428         phi = dst->as_Phi();
 429       }
 430       if (add_multiple && src->in(0) == ex_control) {
 431         // Both are phis.
 432         add_n_reqs(dst, src);
 433       } else {
 434         while (dst->req() < region->req())  add_one_req(dst, src);
 435       }
 436       const Type* srctype = _gvn.type(src);
 437       if (phi->type() != srctype) {
 438         const Type* dsttype = phi->type()->meet_speculative(srctype);
 439         if (phi->type() != dsttype) {
 440           phi->set_type(dsttype);
 441           _gvn.set_type(phi, dsttype);
 442         }
 443       }
 444     }
 445   }
 446   phi_map->merge_replaced_nodes_with(ex_map);
 447 }
 448 
 449 //--------------------------use_exception_state--------------------------------
 450 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
 451   if (failing_internal()) { stop(); return top(); }
 452   Node* region = phi_map->control();
 453   Node* hidden_merge_mark = root();
 454   assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
 455   Node* ex_oop = clear_saved_ex_oop(phi_map);
 456   if (region->in(0) == hidden_merge_mark) {
 457     // Special marking for internal ex-states.  Process the phis now.
 458     region->set_req(0, region);  // now it's an ordinary region
 459     set_jvms(phi_map->jvms());   // ...so now we can use it as a map
 460     // Note: Setting the jvms also sets the bci and sp.
 461     set_control(_gvn.transform(region));
 462     uint tos = jvms()->stkoff() + sp();
 463     for (uint i = 1; i < tos; i++) {
 464       Node* x = phi_map->in(i);
 465       if (x->in(0) == region) {
 466         assert(x->is_Phi(), "expected a special phi");
 467         phi_map->set_req(i, _gvn.transform(x));
 468       }
 469     }
 470     for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
 471       Node* x = mms.memory();
 472       if (x->in(0) == region) {
 473         assert(x->is_Phi(), "nobody else uses a hidden region");
 474         mms.set_memory(_gvn.transform(x));
 475       }
 476     }
 477     if (ex_oop->in(0) == region) {
 478       assert(ex_oop->is_Phi(), "expected a special phi");
 479       ex_oop = _gvn.transform(ex_oop);
 480     }
 481   } else {
 482     set_jvms(phi_map->jvms());
 483   }
 484 
 485   assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
 486   assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
 487   return ex_oop;
 488 }
 489 
 490 //---------------------------------java_bc-------------------------------------
 491 Bytecodes::Code GraphKit::java_bc() const {
 492   ciMethod* method = this->method();
 493   int       bci    = this->bci();
 494   if (method != nullptr && bci != InvocationEntryBci)
 495     return method->java_code_at_bci(bci);
 496   else
 497     return Bytecodes::_illegal;
 498 }
 499 
 500 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
 501                                                           bool must_throw) {
 502     // if the exception capability is set, then we will generate code
 503     // to check the JavaThread.should_post_on_exceptions flag to see
 504     // if we actually need to report exception events (for this
 505     // thread).  If we don't need to report exception events, we will
 506     // take the normal fast path provided by add_exception_events.  If
 507     // exception event reporting is enabled for this thread, we will
 508     // take the uncommon_trap in the BuildCutout below.
 509 
 510     // first must access the should_post_on_exceptions_flag in this thread's JavaThread
 511     Node* jthread = _gvn.transform(new ThreadLocalNode());
 512     Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
 513     Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, MemNode::unordered);
 514 
 515     // Test the should_post_on_exceptions_flag vs. 0
 516     Node* chk = _gvn.transform( new CmpINode(should_post_flag, intcon(0)) );
 517     Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
 518 
 519     // Branch to slow_path if should_post_on_exceptions_flag was true
 520     { BuildCutout unless(this, tst, PROB_MAX);
 521       // Do not try anything fancy if we're notifying the VM on every throw.
 522       // Cf. case Bytecodes::_athrow in parse2.cpp.
 523       uncommon_trap(reason, Deoptimization::Action_none,
 524                     (ciKlass*)nullptr, (char*)nullptr, must_throw);
 525     }
 526 
 527 }
 528 
 529 //------------------------------builtin_throw----------------------------------
 530 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason) {
 531   builtin_throw(reason, builtin_throw_exception(reason), /*allow_too_many_traps*/ true);
 532 }
 533 
 534 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason,
 535                              ciInstance* ex_obj,
 536                              bool allow_too_many_traps) {
 537   // If this throw happens frequently, an uncommon trap might cause
 538   // a performance pothole.  If there is a local exception handler,
 539   // and if this particular bytecode appears to be deoptimizing often,
 540   // let us handle the throw inline, with a preconstructed instance.
 541   // Note:   If the deopt count has blown up, the uncommon trap
 542   // runtime is going to flush this nmethod, not matter what.
 543   if (is_builtin_throw_hot(reason)) {
 544     if (method()->can_omit_stack_trace() && ex_obj != nullptr) {
 545       // If the throw is local, we use a pre-existing instance and
 546       // punt on the backtrace.  This would lead to a missing backtrace
 547       // (a repeat of 4292742) if the backtrace object is ever asked
 548       // for its backtrace.
 549       // Fixing this remaining case of 4292742 requires some flavor of
 550       // escape analysis.  Leave that for the future.
 551       if (env()->jvmti_can_post_on_exceptions()) {
 552         // check if we must post exception events, take uncommon trap if so
 553         uncommon_trap_if_should_post_on_exceptions(reason, true /*must_throw*/);
 554         // here if should_post_on_exceptions is false
 555         // continue on with the normal codegen
 556       }
 557 
 558       // Cheat with a preallocated exception object.
 559       if (C->log() != nullptr)
 560         C->log()->elem("hot_throw preallocated='1' reason='%s'",
 561                        Deoptimization::trap_reason_name(reason));
 562       const TypeInstPtr* ex_con  = TypeInstPtr::make(ex_obj);
 563       Node*              ex_node = _gvn.transform(ConNode::make(ex_con));
 564 
 565       // Clear the detail message of the preallocated exception object.
 566       // Weblogic sometimes mutates the detail message of exceptions
 567       // using reflection.
 568       int offset = java_lang_Throwable::get_detailMessage_offset();
 569       const TypePtr* adr_typ = ex_con->add_offset(offset);
 570 
 571       Node *adr = basic_plus_adr(ex_node, ex_node, offset);
 572       const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
 573       Node *store = access_store_at(ex_node, adr, adr_typ, null(), val_type, T_OBJECT, IN_HEAP);
 574 
 575       if (!method()->has_exception_handlers()) {
 576         // We don't need to preserve the stack if there's no handler as the entire frame is going to be popped anyway.
 577         // This prevents issues with exception handling and late inlining.
 578         set_sp(0);
 579         clean_stack(0);
 580       }
 581 
 582       add_exception_state(make_exception_state(ex_node));
 583       return;
 584     } else if (builtin_throw_too_many_traps(reason, ex_obj)) {
 585       // We cannot afford to take too many traps here. Suffer in the interpreter instead.
 586       assert(allow_too_many_traps, "not allowed");
 587       if (C->log() != nullptr) {
 588         C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
 589                        Deoptimization::trap_reason_name(reason),
 590                        C->trap_count(reason));
 591       }
 592       uncommon_trap(reason, Deoptimization::Action_none,
 593                     (ciKlass*) nullptr, (char*) nullptr,
 594                     true /*must_throw*/);
 595       return;
 596     }
 597   }
 598 
 599   // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
 600   // It won't be much cheaper than bailing to the interp., since we'll
 601   // have to pass up all the debug-info, and the runtime will have to
 602   // create the stack trace.
 603 
 604   // Usual case:  Bail to interpreter.
 605   // Reserve the right to recompile if we haven't seen anything yet.
 606 
 607   // "must_throw" prunes the JVM state to include only the stack, if there
 608   // are no local exception handlers.  This should cut down on register
 609   // allocation time and code size, by drastically reducing the number
 610   // of in-edges on the call to the uncommon trap.
 611   uncommon_trap(reason, Deoptimization::Action_maybe_recompile,
 612                 (ciKlass*) nullptr, (char*) nullptr,
 613                 true /*must_throw*/);
 614 }
 615 
 616 bool GraphKit::is_builtin_throw_hot(Deoptimization::DeoptReason reason) {
 617   // If this particular condition has not yet happened at this
 618   // bytecode, then use the uncommon trap mechanism, and allow for
 619   // a future recompilation if several traps occur here.
 620   // If the throw is hot, try to use a more complicated inline mechanism
 621   // which keeps execution inside the compiled code.
 622   if (ProfileTraps) {
 623     if (too_many_traps(reason)) {
 624       return true;
 625     }
 626     // (If there is no MDO at all, assume it is early in
 627     // execution, and that any deopts are part of the
 628     // startup transient, and don't need to be remembered.)
 629 
 630     // Also, if there is a local exception handler, treat all throws
 631     // as hot if there has been at least one in this method.
 632     if (C->trap_count(reason) != 0 &&
 633         method()->method_data()->trap_count(reason) != 0 &&
 634         has_exception_handler()) {
 635       return true;
 636     }
 637   }
 638   return false;
 639 }
 640 
 641 bool GraphKit::builtin_throw_too_many_traps(Deoptimization::DeoptReason reason,
 642                                             ciInstance* ex_obj) {
 643   if (is_builtin_throw_hot(reason)) {
 644     if (method()->can_omit_stack_trace() && ex_obj != nullptr) {
 645       return false; // no traps; throws preallocated exception instead
 646     }
 647     ciMethod* m = Deoptimization::reason_is_speculate(reason) ? C->method() : nullptr;
 648     if (method()->method_data()->trap_recompiled_at(bci(), m) ||
 649         C->too_many_traps(reason)) {
 650       return true;
 651     }
 652   }
 653   return false;
 654 }
 655 
 656 ciInstance* GraphKit::builtin_throw_exception(Deoptimization::DeoptReason reason) const {
 657   // Preallocated exception objects to use when we don't need the backtrace.
 658   switch (reason) {
 659   case Deoptimization::Reason_null_check:
 660     return env()->NullPointerException_instance();
 661   case Deoptimization::Reason_div0_check:
 662     return env()->ArithmeticException_instance();
 663   case Deoptimization::Reason_range_check:
 664     return env()->ArrayIndexOutOfBoundsException_instance();
 665   case Deoptimization::Reason_class_check:
 666     return env()->ClassCastException_instance();
 667   case Deoptimization::Reason_array_check:
 668     return env()->ArrayStoreException_instance();
 669   default:
 670     return nullptr;
 671   }
 672 }
 673 
 674 GraphKit::SavedState::SavedState(GraphKit* kit) :
 675   _kit(kit),
 676   _sp(kit->sp()),
 677   _jvms(kit->jvms()),
 678   _map(kit->clone_map()),
 679   _discarded(false)
 680 {
 681   for (DUIterator_Fast imax, i = kit->control()->fast_outs(imax); i < imax; i++) {
 682     Node* out = kit->control()->fast_out(i);
 683     if (out->is_CFG()) {
 684       _ctrl_succ.push(out);
 685     }
 686   }
 687 }
 688 
 689 GraphKit::SavedState::~SavedState() {
 690   if (_discarded) {
 691     _kit->destruct_map_clone(_map);
 692     return;
 693   }
 694   _kit->jvms()->set_map(_map);
 695   _kit->jvms()->set_sp(_sp);
 696   _map->set_jvms(_kit->jvms());
 697   _kit->set_map(_map);
 698   _kit->set_sp(_sp);
 699   for (DUIterator_Fast imax, i = _kit->control()->fast_outs(imax); i < imax; i++) {
 700     Node* out = _kit->control()->fast_out(i);
 701     if (out->is_CFG() && out->in(0) == _kit->control() && out != _kit->map() && !_ctrl_succ.member(out)) {
 702       _kit->_gvn.hash_delete(out);
 703       out->set_req(0, _kit->C->top());
 704       _kit->C->record_for_igvn(out);
 705       --i; --imax;
 706       _kit->_gvn.hash_find_insert(out);
 707     }
 708   }
 709 }
 710 
 711 void GraphKit::SavedState::discard() {
 712   _discarded = true;
 713 }
 714 
 715 
 716 //----------------------------PreserveJVMState---------------------------------
 717 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
 718   DEBUG_ONLY(kit->verify_map());
 719   _kit    = kit;
 720   _map    = kit->map();   // preserve the map
 721   _sp     = kit->sp();
 722   kit->set_map(clone_map ? kit->clone_map() : nullptr);
 723 #ifdef ASSERT
 724   _bci    = kit->bci();
 725   Parse* parser = kit->is_Parse();
 726   int block = (parser == nullptr || parser->block() == nullptr) ? -1 : parser->block()->rpo();
 727   _block  = block;
 728 #endif
 729 }
 730 PreserveJVMState::~PreserveJVMState() {
 731   GraphKit* kit = _kit;
 732 #ifdef ASSERT
 733   assert(kit->bci() == _bci, "bci must not shift");
 734   Parse* parser = kit->is_Parse();
 735   int block = (parser == nullptr || parser->block() == nullptr) ? -1 : parser->block()->rpo();
 736   assert(block == _block,    "block must not shift");
 737 #endif
 738   kit->set_map(_map);
 739   kit->set_sp(_sp);
 740 }
 741 
 742 
 743 //-----------------------------BuildCutout-------------------------------------
 744 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
 745   : PreserveJVMState(kit)
 746 {
 747   assert(p->is_Con() || p->is_Bool(), "test must be a bool");
 748   SafePointNode* outer_map = _map;   // preserved map is caller's
 749   SafePointNode* inner_map = kit->map();
 750   IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
 751   outer_map->set_control(kit->gvn().transform( new IfTrueNode(iff) ));
 752   inner_map->set_control(kit->gvn().transform( new IfFalseNode(iff) ));
 753 }
 754 BuildCutout::~BuildCutout() {
 755   GraphKit* kit = _kit;
 756   assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
 757 }
 758 
 759 //---------------------------PreserveReexecuteState----------------------------
 760 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
 761   assert(!kit->stopped(), "must call stopped() before");
 762   _kit    =    kit;
 763   _sp     =    kit->sp();
 764   _reexecute = kit->jvms()->_reexecute;
 765 }
 766 PreserveReexecuteState::~PreserveReexecuteState() {
 767   if (_kit->stopped()) return;
 768   _kit->jvms()->_reexecute = _reexecute;
 769   _kit->set_sp(_sp);
 770 }
 771 
 772 //------------------------------clone_map--------------------------------------
 773 // Implementation of PreserveJVMState
 774 //
 775 // Only clone_map(...) here. If this function is only used in the
 776 // PreserveJVMState class we may want to get rid of this extra
 777 // function eventually and do it all there.
 778 
 779 SafePointNode* GraphKit::clone_map() {
 780   if (map() == nullptr)  return nullptr;
 781 
 782   // Clone the memory edge first
 783   Node* mem = MergeMemNode::make(map()->memory());
 784   gvn().set_type_bottom(mem);
 785 
 786   SafePointNode *clonemap = (SafePointNode*)map()->clone();
 787   JVMState* jvms = this->jvms();
 788   JVMState* clonejvms = jvms->clone_shallow(C);
 789   clonemap->set_memory(mem);
 790   clonemap->set_jvms(clonejvms);
 791   clonejvms->set_map(clonemap);
 792   record_for_igvn(clonemap);
 793   gvn().set_type_bottom(clonemap);
 794   return clonemap;
 795 }
 796 
 797 //-----------------------------destruct_map_clone------------------------------
 798 //
 799 // Order of destruct is important to increase the likelyhood that memory can be re-used. We need
 800 // to destruct/free/delete in the exact opposite order as clone_map().
 801 void GraphKit::destruct_map_clone(SafePointNode* sfp) {
 802   if (sfp == nullptr) return;
 803 
 804   Node* mem = sfp->memory();
 805   JVMState* jvms = sfp->jvms();
 806 
 807   if (jvms != nullptr) {
 808     delete jvms;
 809   }
 810 
 811   remove_for_igvn(sfp);
 812   gvn().clear_type(sfp);
 813   sfp->destruct(&_gvn);
 814 
 815   if (mem != nullptr) {
 816     gvn().clear_type(mem);
 817     mem->destruct(&_gvn);
 818   }
 819 }
 820 
 821 //-----------------------------set_map_clone-----------------------------------
 822 void GraphKit::set_map_clone(SafePointNode* m) {
 823   _map = m;
 824   _map = clone_map();
 825   _map->set_next_exception(nullptr);
 826   DEBUG_ONLY(verify_map());
 827 }
 828 
 829 
 830 //----------------------------kill_dead_locals---------------------------------
 831 // Detect any locals which are known to be dead, and force them to top.
 832 void GraphKit::kill_dead_locals() {
 833   // Consult the liveness information for the locals.  If any
 834   // of them are unused, then they can be replaced by top().  This
 835   // should help register allocation time and cut down on the size
 836   // of the deoptimization information.
 837 
 838   // This call is made from many of the bytecode handling
 839   // subroutines called from the Big Switch in do_one_bytecode.
 840   // Every bytecode which might include a slow path is responsible
 841   // for killing its dead locals.  The more consistent we
 842   // are about killing deads, the fewer useless phis will be
 843   // constructed for them at various merge points.
 844 
 845   // bci can be -1 (InvocationEntryBci).  We return the entry
 846   // liveness for the method.
 847 
 848   if (method() == nullptr || method()->code_size() == 0) {
 849     // We are building a graph for a call to a native method.
 850     // All locals are live.
 851     return;
 852   }
 853 
 854   ResourceMark rm;
 855 
 856   // Consult the liveness information for the locals.  If any
 857   // of them are unused, then they can be replaced by top().  This
 858   // should help register allocation time and cut down on the size
 859   // of the deoptimization information.
 860   MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
 861 
 862   int len = (int)live_locals.size();
 863   assert(len <= jvms()->loc_size(), "too many live locals");
 864   for (int local = 0; local < len; local++) {
 865     if (!live_locals.at(local)) {
 866       set_local(local, top());
 867     }
 868   }
 869 }
 870 
 871 #ifdef ASSERT
 872 //-------------------------dead_locals_are_killed------------------------------
 873 // Return true if all dead locals are set to top in the map.
 874 // Used to assert "clean" debug info at various points.
 875 bool GraphKit::dead_locals_are_killed() {
 876   if (method() == nullptr || method()->code_size() == 0) {
 877     // No locals need to be dead, so all is as it should be.
 878     return true;
 879   }
 880 
 881   // Make sure somebody called kill_dead_locals upstream.
 882   ResourceMark rm;
 883   for (JVMState* jvms = this->jvms(); jvms != nullptr; jvms = jvms->caller()) {
 884     if (jvms->loc_size() == 0)  continue;  // no locals to consult
 885     SafePointNode* map = jvms->map();
 886     ciMethod* method = jvms->method();
 887     int       bci    = jvms->bci();
 888     if (jvms == this->jvms()) {
 889       bci = this->bci();  // it might not yet be synched
 890     }
 891     MethodLivenessResult live_locals = method->liveness_at_bci(bci);
 892     int len = (int)live_locals.size();
 893     if (!live_locals.is_valid() || len == 0)
 894       // This method is trivial, or is poisoned by a breakpoint.
 895       return true;
 896     assert(len == jvms->loc_size(), "live map consistent with locals map");
 897     for (int local = 0; local < len; local++) {
 898       if (!live_locals.at(local) && map->local(jvms, local) != top()) {
 899         if (PrintMiscellaneous && (Verbose || WizardMode)) {
 900           tty->print_cr("Zombie local %d: ", local);
 901           jvms->dump();
 902         }
 903         return false;
 904       }
 905     }
 906   }
 907   return true;
 908 }
 909 
 910 #endif //ASSERT
 911 
 912 // Helper function for enforcing certain bytecodes to reexecute if deoptimization happens.
 913 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
 914   ciMethod* cur_method = jvms->method();
 915   int       cur_bci   = jvms->bci();
 916   if (cur_method != nullptr && cur_bci != InvocationEntryBci) {
 917     Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
 918     return Interpreter::bytecode_should_reexecute(code) ||
 919            (is_anewarray && code == Bytecodes::_multianewarray);
 920     // Reexecute _multianewarray bytecode which was replaced with
 921     // sequence of [a]newarray. See Parse::do_multianewarray().
 922     //
 923     // Note: interpreter should not have it set since this optimization
 924     // is limited by dimensions and guarded by flag so in some cases
 925     // multianewarray() runtime calls will be generated and
 926     // the bytecode should not be reexecutes (stack will not be reset).
 927   } else {
 928     return false;
 929   }
 930 }
 931 
 932 // Helper function for adding JVMState and debug information to node
 933 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
 934   // Add the safepoint edges to the call (or other safepoint).
 935 
 936   // Make sure dead locals are set to top.  This
 937   // should help register allocation time and cut down on the size
 938   // of the deoptimization information.
 939   assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
 940 
 941   // Walk the inline list to fill in the correct set of JVMState's
 942   // Also fill in the associated edges for each JVMState.
 943 
 944   // If the bytecode needs to be reexecuted we need to put
 945   // the arguments back on the stack.
 946   const bool should_reexecute = jvms()->should_reexecute();
 947   JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
 948 
 949   // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
 950   // undefined if the bci is different.  This is normal for Parse but it
 951   // should not happen for LibraryCallKit because only one bci is processed.
 952   assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
 953          "in LibraryCallKit the reexecute bit should not change");
 954 
 955   // If we are guaranteed to throw, we can prune everything but the
 956   // input to the current bytecode.
 957   bool can_prune_locals = false;
 958   uint stack_slots_not_pruned = 0;
 959   int inputs = 0, depth = 0;
 960   if (must_throw) {
 961     assert(method() == youngest_jvms->method(), "sanity");
 962     if (compute_stack_effects(inputs, depth)) {
 963       can_prune_locals = true;
 964       stack_slots_not_pruned = inputs;
 965     }
 966   }
 967 
 968   if (env()->should_retain_local_variables()) {
 969     // At any safepoint, this method can get breakpointed, which would
 970     // then require an immediate deoptimization.
 971     can_prune_locals = false;  // do not prune locals
 972     stack_slots_not_pruned = 0;
 973   }
 974 
 975   // do not scribble on the input jvms
 976   JVMState* out_jvms = youngest_jvms->clone_deep(C);
 977   call->set_jvms(out_jvms); // Start jvms list for call node
 978 
 979   // For a known set of bytecodes, the interpreter should reexecute them if
 980   // deoptimization happens. We set the reexecute state for them here
 981   if (out_jvms->is_reexecute_undefined() && //don't change if already specified
 982       should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
 983 #ifdef ASSERT
 984     int inputs = 0, not_used; // initialized by GraphKit::compute_stack_effects()
 985     assert(method() == youngest_jvms->method(), "sanity");
 986     assert(compute_stack_effects(inputs, not_used), "unknown bytecode: %s", Bytecodes::name(java_bc()));
 987     assert(out_jvms->sp() >= (uint)inputs, "not enough operands for reexecution");
 988 #endif // ASSERT
 989     out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
 990   }
 991 
 992   // Presize the call:
 993   DEBUG_ONLY(uint non_debug_edges = call->req());
 994   call->add_req_batch(top(), youngest_jvms->debug_depth());
 995   assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
 996 
 997   // Set up edges so that the call looks like this:
 998   //  Call [state:] ctl io mem fptr retadr
 999   //       [parms:] parm0 ... parmN
1000   //       [root:]  loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
1001   //    [...mid:]   loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
1002   //       [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
1003   // Note that caller debug info precedes callee debug info.
1004 
1005   // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
1006   uint debug_ptr = call->req();
1007 
1008   // Loop over the map input edges associated with jvms, add them
1009   // to the call node, & reset all offsets to match call node array.
1010   for (JVMState* in_jvms = youngest_jvms; in_jvms != nullptr; ) {
1011     uint debug_end   = debug_ptr;
1012     uint debug_start = debug_ptr - in_jvms->debug_size();
1013     debug_ptr = debug_start;  // back up the ptr
1014 
1015     uint p = debug_start;  // walks forward in [debug_start, debug_end)
1016     uint j, k, l;
1017     SafePointNode* in_map = in_jvms->map();
1018     out_jvms->set_map(call);
1019 
1020     if (can_prune_locals) {
1021       assert(in_jvms->method() == out_jvms->method(), "sanity");
1022       // If the current throw can reach an exception handler in this JVMS,
1023       // then we must keep everything live that can reach that handler.
1024       // As a quick and dirty approximation, we look for any handlers at all.
1025       if (in_jvms->method()->has_exception_handlers()) {
1026         can_prune_locals = false;
1027       }
1028     }
1029 
1030     // Add the Locals
1031     k = in_jvms->locoff();
1032     l = in_jvms->loc_size();
1033     out_jvms->set_locoff(p);
1034     if (!can_prune_locals) {
1035       for (j = 0; j < l; j++)
1036         call->set_req(p++, in_map->in(k+j));
1037     } else {
1038       p += l;  // already set to top above by add_req_batch
1039     }
1040 
1041     // Add the Expression Stack
1042     k = in_jvms->stkoff();
1043     l = in_jvms->sp();
1044     out_jvms->set_stkoff(p);
1045     if (!can_prune_locals) {
1046       for (j = 0; j < l; j++)
1047         call->set_req(p++, in_map->in(k+j));
1048     } else if (can_prune_locals && stack_slots_not_pruned != 0) {
1049       // Divide stack into {S0,...,S1}, where S0 is set to top.
1050       uint s1 = stack_slots_not_pruned;
1051       stack_slots_not_pruned = 0;  // for next iteration
1052       if (s1 > l)  s1 = l;
1053       uint s0 = l - s1;
1054       p += s0;  // skip the tops preinstalled by add_req_batch
1055       for (j = s0; j < l; j++)
1056         call->set_req(p++, in_map->in(k+j));
1057     } else {
1058       p += l;  // already set to top above by add_req_batch
1059     }
1060 
1061     // Add the Monitors
1062     k = in_jvms->monoff();
1063     l = in_jvms->mon_size();
1064     out_jvms->set_monoff(p);
1065     for (j = 0; j < l; j++)
1066       call->set_req(p++, in_map->in(k+j));
1067 
1068     // Copy any scalar object fields.
1069     k = in_jvms->scloff();
1070     l = in_jvms->scl_size();
1071     out_jvms->set_scloff(p);
1072     for (j = 0; j < l; j++)
1073       call->set_req(p++, in_map->in(k+j));
1074 
1075     // Finish the new jvms.
1076     out_jvms->set_endoff(p);
1077 
1078     assert(out_jvms->endoff()     == debug_end,             "fill ptr must match");
1079     assert(out_jvms->depth()      == in_jvms->depth(),      "depth must match");
1080     assert(out_jvms->loc_size()   == in_jvms->loc_size(),   "size must match");
1081     assert(out_jvms->mon_size()   == in_jvms->mon_size(),   "size must match");
1082     assert(out_jvms->scl_size()   == in_jvms->scl_size(),   "size must match");
1083     assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
1084 
1085     // Update the two tail pointers in parallel.
1086     out_jvms = out_jvms->caller();
1087     in_jvms  = in_jvms->caller();
1088   }
1089 
1090   assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
1091 
1092   // Test the correctness of JVMState::debug_xxx accessors:
1093   assert(call->jvms()->debug_start() == non_debug_edges, "");
1094   assert(call->jvms()->debug_end()   == call->req(), "");
1095   assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
1096 }
1097 
1098 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
1099   Bytecodes::Code code = java_bc();
1100   if (code == Bytecodes::_wide) {
1101     code = method()->java_code_at_bci(bci() + 1);
1102   }
1103 
1104   if (code != Bytecodes::_illegal) {
1105     depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1106   }
1107 
1108   auto rsize = [&]() {
1109     assert(code != Bytecodes::_illegal, "code is illegal!");
1110     BasicType rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1111     return (rtype < T_CONFLICT) ? type2size[rtype] : 0;
1112   };
1113 
1114   switch (code) {
1115   case Bytecodes::_illegal:
1116     return false;
1117 
1118   case Bytecodes::_ldc:
1119   case Bytecodes::_ldc_w:
1120   case Bytecodes::_ldc2_w:
1121     inputs = 0;
1122     break;
1123 
1124   case Bytecodes::_dup:         inputs = 1;  break;
1125   case Bytecodes::_dup_x1:      inputs = 2;  break;
1126   case Bytecodes::_dup_x2:      inputs = 3;  break;
1127   case Bytecodes::_dup2:        inputs = 2;  break;
1128   case Bytecodes::_dup2_x1:     inputs = 3;  break;
1129   case Bytecodes::_dup2_x2:     inputs = 4;  break;
1130   case Bytecodes::_swap:        inputs = 2;  break;
1131   case Bytecodes::_arraylength: inputs = 1;  break;
1132 
1133   case Bytecodes::_getstatic:
1134   case Bytecodes::_putstatic:
1135   case Bytecodes::_getfield:
1136   case Bytecodes::_putfield:
1137     {
1138       bool ignored_will_link;
1139       ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1140       int      size  = field->type()->size();
1141       bool is_get = (depth >= 0), is_static = (depth & 1);
1142       inputs = (is_static ? 0 : 1);
1143       if (is_get) {
1144         depth = size - inputs;
1145       } else {
1146         inputs += size;        // putxxx pops the value from the stack
1147         depth = - inputs;
1148       }
1149     }
1150     break;
1151 
1152   case Bytecodes::_invokevirtual:
1153   case Bytecodes::_invokespecial:
1154   case Bytecodes::_invokestatic:
1155   case Bytecodes::_invokedynamic:
1156   case Bytecodes::_invokeinterface:
1157     {
1158       bool ignored_will_link;
1159       ciSignature* declared_signature = nullptr;
1160       ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1161       assert(declared_signature != nullptr, "cannot be null");
1162       inputs   = declared_signature->arg_size_for_bc(code);
1163       int size = declared_signature->return_type()->size();
1164       depth = size - inputs;
1165     }
1166     break;
1167 
1168   case Bytecodes::_multianewarray:
1169     {
1170       ciBytecodeStream iter(method());
1171       iter.reset_to_bci(bci());
1172       iter.next();
1173       inputs = iter.get_dimensions();
1174       assert(rsize() == 1, "");
1175       depth = 1 - inputs;
1176     }
1177     break;
1178 
1179   case Bytecodes::_ireturn:
1180   case Bytecodes::_lreturn:
1181   case Bytecodes::_freturn:
1182   case Bytecodes::_dreturn:
1183   case Bytecodes::_areturn:
1184     assert(rsize() == -depth, "");
1185     inputs = -depth;
1186     break;
1187 
1188   case Bytecodes::_jsr:
1189   case Bytecodes::_jsr_w:
1190     inputs = 0;
1191     depth  = 1;                  // S.B. depth=1, not zero
1192     break;
1193 
1194   default:
1195     // bytecode produces a typed result
1196     inputs = rsize() - depth;
1197     assert(inputs >= 0, "");
1198     break;
1199   }
1200 
1201 #ifdef ASSERT
1202   // spot check
1203   int outputs = depth + inputs;
1204   assert(outputs >= 0, "sanity");
1205   switch (code) {
1206   case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1207   case Bytecodes::_athrow:    assert(inputs == 1 && outputs == 0, ""); break;
1208   case Bytecodes::_aload_0:   assert(inputs == 0 && outputs == 1, ""); break;
1209   case Bytecodes::_return:    assert(inputs == 0 && outputs == 0, ""); break;
1210   case Bytecodes::_drem:      assert(inputs == 4 && outputs == 2, ""); break;
1211   default:                    break;
1212   }
1213 #endif //ASSERT
1214 
1215   return true;
1216 }
1217 
1218 
1219 
1220 //------------------------------basic_plus_adr---------------------------------
1221 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1222   // short-circuit a common case
1223   if (offset == MakeConX(0)) {
1224     return ptr;
1225   }
1226 #ifdef ASSERT
1227   // Both 32-bit and 64-bit zeros should have been handled by the previous `if`
1228   // statement, so if we see either 32-bit or 64-bit zeros here, then we have a
1229   // problem.
1230   if (offset->is_Con()) {
1231     const Type* t = offset->bottom_type();
1232     bool is_zero_int = t->isa_int() && t->is_int()->get_con() == 0;
1233     bool is_zero_long = t->isa_long() && t->is_long()->get_con() == 0;
1234     assert(!is_zero_int && !is_zero_long,
1235            "Unexpected zero offset - should have matched MakeConX(0)");
1236   }
1237 #endif
1238   return _gvn.transform( new AddPNode(base, ptr, offset) );
1239 }
1240 
1241 Node* GraphKit::ConvI2L(Node* offset) {
1242   // short-circuit a common case
1243   jint offset_con = find_int_con(offset, Type::OffsetBot);
1244   if (offset_con != Type::OffsetBot) {
1245     return longcon((jlong) offset_con);
1246   }
1247   return _gvn.transform( new ConvI2LNode(offset));
1248 }
1249 
1250 Node* GraphKit::ConvI2UL(Node* offset) {
1251   juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1252   if (offset_con != (juint) Type::OffsetBot) {
1253     return longcon((julong) offset_con);
1254   }
1255   Node* conv = _gvn.transform( new ConvI2LNode(offset));
1256   Node* mask = _gvn.transform(ConLNode::make((julong) max_juint));
1257   return _gvn.transform( new AndLNode(conv, mask) );
1258 }
1259 
1260 Node* GraphKit::ConvL2I(Node* offset) {
1261   // short-circuit a common case
1262   jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1263   if (offset_con != (jlong)Type::OffsetBot) {
1264     return intcon((int) offset_con);
1265   }
1266   return _gvn.transform( new ConvL2INode(offset));
1267 }
1268 
1269 //-------------------------load_object_klass-----------------------------------
1270 Node* GraphKit::load_object_klass(Node* obj) {
1271   // Special-case a fresh allocation to avoid building nodes:
1272   Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1273   if (akls != nullptr)  return akls;
1274   Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1275   return _gvn.transform(LoadKlassNode::make(_gvn, immutable_memory(), k_adr, TypeInstPtr::KLASS));
1276 }
1277 
1278 //-------------------------load_array_length-----------------------------------
1279 Node* GraphKit::load_array_length(Node* array) {
1280   // Special-case a fresh allocation to avoid building nodes:
1281   AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array);
1282   Node *alen;
1283   if (alloc == nullptr) {
1284     Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1285     alen = _gvn.transform( new LoadRangeNode(nullptr, immutable_memory(), r_adr, TypeInt::POS));
1286   } else {
1287     alen = array_ideal_length(alloc, _gvn.type(array)->is_oopptr(), false);
1288   }
1289   return alen;
1290 }
1291 
1292 Node* GraphKit::array_ideal_length(AllocateArrayNode* alloc,
1293                                    const TypeOopPtr* oop_type,
1294                                    bool replace_length_in_map) {
1295   Node* length = alloc->Ideal_length();
1296   if (replace_length_in_map == false || map()->find_edge(length) >= 0) {
1297     Node* ccast = alloc->make_ideal_length(oop_type, &_gvn);
1298     if (ccast != length) {
1299       // do not transform ccast here, it might convert to top node for
1300       // negative array length and break assumptions in parsing stage.
1301       _gvn.set_type_bottom(ccast);
1302       record_for_igvn(ccast);
1303       if (replace_length_in_map) {
1304         replace_in_map(length, ccast);
1305       }
1306       return ccast;
1307     }
1308   }
1309   return length;
1310 }
1311 
1312 //------------------------------do_null_check----------------------------------
1313 // Helper function to do a null pointer check.  Returned value is
1314 // the incoming address with null casted away.  You are allowed to use the
1315 // not-null value only if you are control dependent on the test.
1316 #ifndef PRODUCT
1317 extern uint explicit_null_checks_inserted,
1318             explicit_null_checks_elided;
1319 #endif
1320 Node* GraphKit::null_check_common(Node* value, BasicType type,
1321                                   // optional arguments for variations:
1322                                   bool assert_null,
1323                                   Node* *null_control,
1324                                   bool speculative) {
1325   assert(!assert_null || null_control == nullptr, "not both at once");
1326   if (stopped())  return top();
1327   NOT_PRODUCT(explicit_null_checks_inserted++);
1328 
1329   // Construct null check
1330   Node *chk = nullptr;
1331   switch(type) {
1332     case T_LONG   : chk = new CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1333     case T_INT    : chk = new CmpINode(value, _gvn.intcon(0)); break;
1334     case T_ARRAY  : // fall through
1335       type = T_OBJECT;  // simplify further tests
1336     case T_OBJECT : {
1337       const Type *t = _gvn.type( value );
1338 
1339       const TypeOopPtr* tp = t->isa_oopptr();
1340       if (tp != nullptr && !tp->is_loaded()
1341           // Only for do_null_check, not any of its siblings:
1342           && !assert_null && null_control == nullptr) {
1343         // Usually, any field access or invocation on an unloaded oop type
1344         // will simply fail to link, since the statically linked class is
1345         // likely also to be unloaded.  However, in -Xcomp mode, sometimes
1346         // the static class is loaded but the sharper oop type is not.
1347         // Rather than checking for this obscure case in lots of places,
1348         // we simply observe that a null check on an unloaded class
1349         // will always be followed by a nonsense operation, so we
1350         // can just issue the uncommon trap here.
1351         // Our access to the unloaded class will only be correct
1352         // after it has been loaded and initialized, which requires
1353         // a trip through the interpreter.
1354         ciKlass* klass = tp->unloaded_klass();
1355 #ifndef PRODUCT
1356         if (WizardMode) { tty->print("Null check of unloaded "); klass->print(); tty->cr(); }
1357 #endif
1358         uncommon_trap(Deoptimization::Reason_unloaded,
1359                       Deoptimization::Action_reinterpret,
1360                       klass, "!loaded");
1361         return top();
1362       }
1363 
1364       if (assert_null) {
1365         // See if the type is contained in NULL_PTR.
1366         // If so, then the value is already null.
1367         if (t->higher_equal(TypePtr::NULL_PTR)) {
1368           NOT_PRODUCT(explicit_null_checks_elided++);
1369           return value;           // Elided null assert quickly!
1370         }
1371       } else {
1372         // See if mixing in the null pointer changes type.
1373         // If so, then the null pointer was not allowed in the original
1374         // type.  In other words, "value" was not-null.
1375         if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1376           // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1377           NOT_PRODUCT(explicit_null_checks_elided++);
1378           return value;           // Elided null check quickly!
1379         }
1380       }
1381       chk = new CmpPNode( value, null() );
1382       break;
1383     }
1384 
1385     default:
1386       fatal("unexpected type: %s", type2name(type));
1387   }
1388   assert(chk != nullptr, "sanity check");
1389   chk = _gvn.transform(chk);
1390 
1391   BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1392   BoolNode *btst = new BoolNode( chk, btest);
1393   Node   *tst = _gvn.transform( btst );
1394 
1395   //-----------
1396   // if peephole optimizations occurred, a prior test existed.
1397   // If a prior test existed, maybe it dominates as we can avoid this test.
1398   if (tst != btst && type == T_OBJECT) {
1399     // At this point we want to scan up the CFG to see if we can
1400     // find an identical test (and so avoid this test altogether).
1401     Node *cfg = control();
1402     int depth = 0;
1403     while( depth < 16 ) {       // Limit search depth for speed
1404       if( cfg->Opcode() == Op_IfTrue &&
1405           cfg->in(0)->in(1) == tst ) {
1406         // Found prior test.  Use "cast_not_null" to construct an identical
1407         // CastPP (and hence hash to) as already exists for the prior test.
1408         // Return that casted value.
1409         if (assert_null) {
1410           replace_in_map(value, null());
1411           return null();  // do not issue the redundant test
1412         }
1413         Node *oldcontrol = control();
1414         set_control(cfg);
1415         Node *res = cast_not_null(value);
1416         set_control(oldcontrol);
1417         NOT_PRODUCT(explicit_null_checks_elided++);
1418         return res;
1419       }
1420       cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1421       if (cfg == nullptr)  break;  // Quit at region nodes
1422       depth++;
1423     }
1424   }
1425 
1426   //-----------
1427   // Branch to failure if null
1428   float ok_prob = PROB_MAX;  // a priori estimate:  nulls never happen
1429   Deoptimization::DeoptReason reason;
1430   if (assert_null) {
1431     reason = Deoptimization::reason_null_assert(speculative);
1432   } else if (type == T_OBJECT) {
1433     reason = Deoptimization::reason_null_check(speculative);
1434   } else {
1435     reason = Deoptimization::Reason_div0_check;
1436   }
1437   // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1438   // ciMethodData::has_trap_at will return a conservative -1 if any
1439   // must-be-null assertion has failed.  This could cause performance
1440   // problems for a method after its first do_null_assert failure.
1441   // Consider using 'Reason_class_check' instead?
1442 
1443   // To cause an implicit null check, we set the not-null probability
1444   // to the maximum (PROB_MAX).  For an explicit check the probability
1445   // is set to a smaller value.
1446   if (null_control != nullptr || too_many_traps(reason)) {
1447     // probability is less likely
1448     ok_prob =  PROB_LIKELY_MAG(3);
1449   } else if (!assert_null &&
1450              (ImplicitNullCheckThreshold > 0) &&
1451              method() != nullptr &&
1452              (method()->method_data()->trap_count(reason)
1453               >= (uint)ImplicitNullCheckThreshold)) {
1454     ok_prob =  PROB_LIKELY_MAG(3);
1455   }
1456 
1457   if (null_control != nullptr) {
1458     IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1459     Node* null_true = _gvn.transform( new IfFalseNode(iff));
1460     set_control(      _gvn.transform( new IfTrueNode(iff)));
1461 #ifndef PRODUCT
1462     if (null_true == top()) {
1463       explicit_null_checks_elided++;
1464     }
1465 #endif
1466     (*null_control) = null_true;
1467   } else {
1468     BuildCutout unless(this, tst, ok_prob);
1469     // Check for optimizer eliding test at parse time
1470     if (stopped()) {
1471       // Failure not possible; do not bother making uncommon trap.
1472       NOT_PRODUCT(explicit_null_checks_elided++);
1473     } else if (assert_null) {
1474       uncommon_trap(reason,
1475                     Deoptimization::Action_make_not_entrant,
1476                     nullptr, "assert_null");
1477     } else {
1478       replace_in_map(value, zerocon(type));
1479       builtin_throw(reason);
1480     }
1481   }
1482 
1483   // Must throw exception, fall-thru not possible?
1484   if (stopped()) {
1485     return top();               // No result
1486   }
1487 
1488   if (assert_null) {
1489     // Cast obj to null on this path.
1490     replace_in_map(value, zerocon(type));
1491     return zerocon(type);
1492   }
1493 
1494   // Cast obj to not-null on this path, if there is no null_control.
1495   // (If there is a null_control, a non-null value may come back to haunt us.)
1496   if (type == T_OBJECT) {
1497     Node* cast = cast_not_null(value, false);
1498     if (null_control == nullptr || (*null_control) == top())
1499       replace_in_map(value, cast);
1500     value = cast;
1501   }
1502 
1503   return value;
1504 }
1505 
1506 
1507 //------------------------------cast_not_null----------------------------------
1508 // Cast obj to not-null on this path
1509 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1510   const Type *t = _gvn.type(obj);
1511   const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1512   // Object is already not-null?
1513   if( t == t_not_null ) return obj;
1514 
1515   Node* cast = new CastPPNode(control(), obj,t_not_null);
1516   cast = _gvn.transform( cast );
1517 
1518   // Scan for instances of 'obj' in the current JVM mapping.
1519   // These instances are known to be not-null after the test.
1520   if (do_replace_in_map)
1521     replace_in_map(obj, cast);
1522 
1523   return cast;                  // Return casted value
1524 }
1525 
1526 // Sometimes in intrinsics, we implicitly know an object is not null
1527 // (there's no actual null check) so we can cast it to not null. In
1528 // the course of optimizations, the input to the cast can become null.
1529 // In that case that data path will die and we need the control path
1530 // to become dead as well to keep the graph consistent. So we have to
1531 // add a check for null for which one branch can't be taken. It uses
1532 // an OpaqueConstantBool node that will cause the check to be removed after loop
1533 // opts so the test goes away and the compiled code doesn't execute a
1534 // useless check.
1535 Node* GraphKit::must_be_not_null(Node* value, bool do_replace_in_map) {
1536   if (!TypePtr::NULL_PTR->higher_equal(_gvn.type(value))) {
1537     return value;
1538   }
1539   Node* chk = _gvn.transform(new CmpPNode(value, null()));
1540   Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::ne));
1541   Node* opaq = _gvn.transform(new OpaqueConstantBoolNode(C, tst, true));
1542   IfNode* iff = new IfNode(control(), opaq, PROB_MAX, COUNT_UNKNOWN);
1543   _gvn.set_type(iff, iff->Value(&_gvn));
1544   if (!tst->is_Con()) {
1545     record_for_igvn(iff);
1546   }
1547   Node *if_f = _gvn.transform(new IfFalseNode(iff));
1548   Node *frame = _gvn.transform(new ParmNode(C->start(), TypeFunc::FramePtr));
1549   halt(if_f, frame, "unexpected null in intrinsic");
1550   Node *if_t = _gvn.transform(new IfTrueNode(iff));
1551   set_control(if_t);
1552   return cast_not_null(value, do_replace_in_map);
1553 }
1554 
1555 
1556 //--------------------------replace_in_map-------------------------------------
1557 void GraphKit::replace_in_map(Node* old, Node* neww) {
1558   if (old == neww) {
1559     return;
1560   }
1561 
1562   map()->replace_edge(old, neww);
1563 
1564   // Note: This operation potentially replaces any edge
1565   // on the map.  This includes locals, stack, and monitors
1566   // of the current (innermost) JVM state.
1567 
1568   // don't let inconsistent types from profiling escape this
1569   // method
1570 
1571   const Type* told = _gvn.type(old);
1572   const Type* tnew = _gvn.type(neww);
1573 
1574   if (!tnew->higher_equal(told)) {
1575     return;
1576   }
1577 
1578   map()->record_replaced_node(old, neww);
1579 }
1580 
1581 
1582 //=============================================================================
1583 //--------------------------------memory---------------------------------------
1584 Node* GraphKit::memory(uint alias_idx) {
1585   MergeMemNode* mem = merged_memory();
1586   Node* p = mem->memory_at(alias_idx);
1587   assert(p != mem->empty_memory(), "empty");
1588   _gvn.set_type(p, Type::MEMORY);  // must be mapped
1589   return p;
1590 }
1591 
1592 //-----------------------------reset_memory------------------------------------
1593 Node* GraphKit::reset_memory() {
1594   Node* mem = map()->memory();
1595   // do not use this node for any more parsing!
1596   DEBUG_ONLY( map()->set_memory((Node*)nullptr) );
1597   return _gvn.transform( mem );
1598 }
1599 
1600 //------------------------------set_all_memory---------------------------------
1601 void GraphKit::set_all_memory(Node* newmem) {
1602   Node* mergemem = MergeMemNode::make(newmem);
1603   gvn().set_type_bottom(mergemem);
1604   map()->set_memory(mergemem);
1605 }
1606 
1607 //------------------------------set_all_memory_call----------------------------
1608 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1609   Node* newmem = _gvn.transform( new ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1610   set_all_memory(newmem);
1611 }
1612 
1613 //=============================================================================
1614 //
1615 // parser factory methods for MemNodes
1616 //
1617 // These are layered on top of the factory methods in LoadNode and StoreNode,
1618 // and integrate with the parser's memory state and _gvn engine.
1619 //
1620 
1621 // factory methods in "int adr_idx"
1622 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1623                           MemNode::MemOrd mo,
1624                           LoadNode::ControlDependency control_dependency,
1625                           bool require_atomic_access,
1626                           bool unaligned,
1627                           bool mismatched,
1628                           bool unsafe,
1629                           uint8_t barrier_data) {
1630   int adr_idx = C->get_alias_index(_gvn.type(adr)->isa_ptr());
1631   assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1632   const TypePtr* adr_type = nullptr; // debug-mode-only argument
1633   DEBUG_ONLY(adr_type = C->get_adr_type(adr_idx));
1634   Node* mem = memory(adr_idx);
1635   Node* ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, require_atomic_access, unaligned, mismatched, unsafe, barrier_data);
1636   ld = _gvn.transform(ld);
1637   if (((bt == T_OBJECT) && C->do_escape_analysis()) || C->eliminate_boxing()) {
1638     // Improve graph before escape analysis and boxing elimination.
1639     record_for_igvn(ld);
1640     if (ld->is_DecodeN()) {
1641       // Also record the actual load (LoadN) in case ld is DecodeN. In some
1642       // rare corner cases, ld->in(1) can be something other than LoadN (e.g.,
1643       // a Phi). Recording such cases is still perfectly sound, but may be
1644       // unnecessary and result in some minor IGVN overhead.
1645       record_for_igvn(ld->in(1));
1646     }
1647   }
1648   return ld;
1649 }
1650 
1651 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1652                                 MemNode::MemOrd mo,
1653                                 bool require_atomic_access,
1654                                 bool unaligned,
1655                                 bool mismatched,
1656                                 bool unsafe,
1657                                 int barrier_data) {
1658   int adr_idx = C->get_alias_index(_gvn.type(adr)->isa_ptr());
1659   assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1660   const TypePtr* adr_type = nullptr;
1661   DEBUG_ONLY(adr_type = C->get_adr_type(adr_idx));
1662   Node *mem = memory(adr_idx);
1663   Node* st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo, require_atomic_access);
1664   if (unaligned) {
1665     st->as_Store()->set_unaligned_access();
1666   }
1667   if (mismatched) {
1668     st->as_Store()->set_mismatched_access();
1669   }
1670   if (unsafe) {
1671     st->as_Store()->set_unsafe_access();
1672   }
1673   st->as_Store()->set_barrier_data(barrier_data);
1674   st = _gvn.transform(st);
1675   set_memory(st, adr_idx);
1676   // Back-to-back stores can only remove intermediate store with DU info
1677   // so push on worklist for optimizer.
1678   if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1679     record_for_igvn(st);
1680 
1681   return st;
1682 }
1683 
1684 Node* GraphKit::access_store_at(Node* obj,
1685                                 Node* adr,
1686                                 const TypePtr* adr_type,
1687                                 Node* val,
1688                                 const Type* val_type,
1689                                 BasicType bt,
1690                                 DecoratorSet decorators) {
1691   // Transformation of a value which could be null pointer (CastPP #null)
1692   // could be delayed during Parse (for example, in adjust_map_after_if()).
1693   // Execute transformation here to avoid barrier generation in such case.
1694   if (_gvn.type(val) == TypePtr::NULL_PTR) {
1695     val = _gvn.makecon(TypePtr::NULL_PTR);
1696   }
1697 
1698   if (stopped()) {
1699     return top(); // Dead path ?
1700   }
1701 
1702   assert(val != nullptr, "not dead path");
1703 
1704   C2AccessValuePtr addr(adr, adr_type);
1705   C2AccessValue value(val, val_type);
1706   C2ParseAccess access(this, decorators | C2_WRITE_ACCESS, bt, obj, addr);
1707   if (access.is_raw()) {
1708     return _barrier_set->BarrierSetC2::store_at(access, value);
1709   } else {
1710     return _barrier_set->store_at(access, value);
1711   }
1712 }
1713 
1714 Node* GraphKit::access_load_at(Node* obj,   // containing obj
1715                                Node* adr,   // actual address to store val at
1716                                const TypePtr* adr_type,
1717                                const Type* val_type,
1718                                BasicType bt,
1719                                DecoratorSet decorators) {
1720   if (stopped()) {
1721     return top(); // Dead path ?
1722   }
1723 
1724   SavedState old_state(this);
1725   C2AccessValuePtr addr(adr, adr_type);
1726   C2ParseAccess access(this, decorators | C2_READ_ACCESS, bt, obj, addr);
1727   Node* load;
1728   if (access.is_raw()) {
1729     load = _barrier_set->BarrierSetC2::load_at(access, val_type);
1730   } else {
1731     load = _barrier_set->load_at(access, val_type);
1732   }
1733 
1734   // Restore the previous state only if the load got folded to a constant
1735   // and we can discard any barriers that might have been added.
1736   if (load == nullptr || !load->is_Con()) {
1737     old_state.discard();
1738   }
1739   return load;
1740 }
1741 
1742 Node* GraphKit::access_load(Node* adr,   // actual address to load val at
1743                             const Type* val_type,
1744                             BasicType bt,
1745                             DecoratorSet decorators) {
1746   if (stopped()) {
1747     return top(); // Dead path ?
1748   }
1749 
1750   SavedState old_state(this);
1751   C2AccessValuePtr addr(adr, adr->bottom_type()->is_ptr());
1752   C2ParseAccess access(this, decorators | C2_READ_ACCESS, bt, nullptr, addr);
1753   Node* load;
1754   if (access.is_raw()) {
1755     load = _barrier_set->BarrierSetC2::load_at(access, val_type);
1756   } else {
1757     load = _barrier_set->load_at(access, val_type);
1758   }
1759 
1760   // Restore the previous state only if the load got folded to a constant
1761   // and we can discard any barriers that might have been added.
1762   if (load == nullptr || !load->is_Con()) {
1763     old_state.discard();
1764   }
1765   return load;
1766 }
1767 
1768 Node* GraphKit::access_atomic_cmpxchg_val_at(Node* obj,
1769                                              Node* adr,
1770                                              const TypePtr* adr_type,
1771                                              int alias_idx,
1772                                              Node* expected_val,
1773                                              Node* new_val,
1774                                              const Type* value_type,
1775                                              BasicType bt,
1776                                              DecoratorSet decorators) {
1777   C2AccessValuePtr addr(adr, adr_type);
1778   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1779                         bt, obj, addr, alias_idx);
1780   if (access.is_raw()) {
1781     return _barrier_set->BarrierSetC2::atomic_cmpxchg_val_at(access, expected_val, new_val, value_type);
1782   } else {
1783     return _barrier_set->atomic_cmpxchg_val_at(access, expected_val, new_val, value_type);
1784   }
1785 }
1786 
1787 Node* GraphKit::access_atomic_cmpxchg_bool_at(Node* obj,
1788                                               Node* adr,
1789                                               const TypePtr* adr_type,
1790                                               int alias_idx,
1791                                               Node* expected_val,
1792                                               Node* new_val,
1793                                               const Type* value_type,
1794                                               BasicType bt,
1795                                               DecoratorSet decorators) {
1796   C2AccessValuePtr addr(adr, adr_type);
1797   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1798                         bt, obj, addr, alias_idx);
1799   if (access.is_raw()) {
1800     return _barrier_set->BarrierSetC2::atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type);
1801   } else {
1802     return _barrier_set->atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type);
1803   }
1804 }
1805 
1806 Node* GraphKit::access_atomic_xchg_at(Node* obj,
1807                                       Node* adr,
1808                                       const TypePtr* adr_type,
1809                                       int alias_idx,
1810                                       Node* new_val,
1811                                       const Type* value_type,
1812                                       BasicType bt,
1813                                       DecoratorSet decorators) {
1814   C2AccessValuePtr addr(adr, adr_type);
1815   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1816                         bt, obj, addr, alias_idx);
1817   if (access.is_raw()) {
1818     return _barrier_set->BarrierSetC2::atomic_xchg_at(access, new_val, value_type);
1819   } else {
1820     return _barrier_set->atomic_xchg_at(access, new_val, value_type);
1821   }
1822 }
1823 
1824 Node* GraphKit::access_atomic_add_at(Node* obj,
1825                                      Node* adr,
1826                                      const TypePtr* adr_type,
1827                                      int alias_idx,
1828                                      Node* new_val,
1829                                      const Type* value_type,
1830                                      BasicType bt,
1831                                      DecoratorSet decorators) {
1832   C2AccessValuePtr addr(adr, adr_type);
1833   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS, bt, obj, addr, alias_idx);
1834   if (access.is_raw()) {
1835     return _barrier_set->BarrierSetC2::atomic_add_at(access, new_val, value_type);
1836   } else {
1837     return _barrier_set->atomic_add_at(access, new_val, value_type);
1838   }
1839 }
1840 
1841 void GraphKit::access_clone(Node* src, Node* dst, Node* size, bool is_array) {
1842   return _barrier_set->clone(this, src, dst, size, is_array);
1843 }
1844 
1845 //-------------------------array_element_address-------------------------
1846 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1847                                       const TypeInt* sizetype, Node* ctrl) {
1848   uint shift  = exact_log2(type2aelembytes(elembt));
1849   uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1850 
1851   // short-circuit a common case (saves lots of confusing waste motion)
1852   jint idx_con = find_int_con(idx, -1);
1853   if (idx_con >= 0) {
1854     intptr_t offset = header + ((intptr_t)idx_con << shift);
1855     return basic_plus_adr(ary, offset);
1856   }
1857 
1858   // must be correct type for alignment purposes
1859   Node* base  = basic_plus_adr(ary, header);
1860   idx = Compile::conv_I2X_index(&_gvn, idx, sizetype, ctrl);
1861   Node* scale = _gvn.transform( new LShiftXNode(idx, intcon(shift)) );
1862   return basic_plus_adr(ary, base, scale);
1863 }
1864 
1865 //-------------------------load_array_element-------------------------
1866 Node* GraphKit::load_array_element(Node* ary, Node* idx, const TypeAryPtr* arytype, bool set_ctrl) {
1867   const Type* elemtype = arytype->elem();
1868   BasicType elembt = elemtype->array_element_basic_type();
1869   Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1870   if (elembt == T_NARROWOOP) {
1871     elembt = T_OBJECT; // To satisfy switch in LoadNode::make()
1872   }
1873   Node* ld = access_load_at(ary, adr, arytype, elemtype, elembt,
1874                             IN_HEAP | IS_ARRAY | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0));
1875   return ld;
1876 }
1877 
1878 //-------------------------set_arguments_for_java_call-------------------------
1879 // Arguments (pre-popped from the stack) are taken from the JVMS.
1880 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1881   // Add the call arguments:
1882   uint nargs = call->method()->arg_size();
1883   for (uint i = 0; i < nargs; i++) {
1884     Node* arg = argument(i);
1885     call->init_req(i + TypeFunc::Parms, arg);
1886   }
1887 }
1888 
1889 //---------------------------set_edges_for_java_call---------------------------
1890 // Connect a newly created call into the current JVMS.
1891 // A return value node (if any) is returned from set_edges_for_java_call.
1892 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1893 
1894   // Add the predefined inputs:
1895   call->init_req( TypeFunc::Control, control() );
1896   call->init_req( TypeFunc::I_O    , i_o() );
1897   call->init_req( TypeFunc::Memory , reset_memory() );
1898   call->init_req( TypeFunc::FramePtr, frameptr() );
1899   call->init_req( TypeFunc::ReturnAdr, top() );
1900 
1901   add_safepoint_edges(call, must_throw);
1902 
1903   Node* xcall = _gvn.transform(call);
1904 
1905   if (xcall == top()) {
1906     set_control(top());
1907     return;
1908   }
1909   assert(xcall == call, "call identity is stable");
1910 
1911   // Re-use the current map to produce the result.
1912 
1913   set_control(_gvn.transform(new ProjNode(call, TypeFunc::Control)));
1914   set_i_o(    _gvn.transform(new ProjNode(call, TypeFunc::I_O    , separate_io_proj)));
1915   set_all_memory_call(xcall, separate_io_proj);
1916 
1917   //return xcall;   // no need, caller already has it
1918 }
1919 
1920 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj, bool deoptimize) {
1921   if (stopped())  return top();  // maybe the call folded up?
1922 
1923   // Capture the return value, if any.
1924   Node* ret;
1925   if (call->method() == nullptr ||
1926       call->method()->return_type()->basic_type() == T_VOID)
1927         ret = top();
1928   else  ret = _gvn.transform(new ProjNode(call, TypeFunc::Parms));
1929 
1930   // Note:  Since any out-of-line call can produce an exception,
1931   // we always insert an I_O projection from the call into the result.
1932 
1933   make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj, deoptimize);
1934 
1935   if (separate_io_proj) {
1936     // The caller requested separate projections be used by the fall
1937     // through and exceptional paths, so replace the projections for
1938     // the fall through path.
1939     set_i_o(_gvn.transform( new ProjNode(call, TypeFunc::I_O) ));
1940     set_all_memory(_gvn.transform( new ProjNode(call, TypeFunc::Memory) ));
1941   }
1942   return ret;
1943 }
1944 
1945 //--------------------set_predefined_input_for_runtime_call--------------------
1946 // Reading and setting the memory state is way conservative here.
1947 // The real problem is that I am not doing real Type analysis on memory,
1948 // so I cannot distinguish card mark stores from other stores.  Across a GC
1949 // point the Store Barrier and the card mark memory has to agree.  I cannot
1950 // have a card mark store and its barrier split across the GC point from
1951 // either above or below.  Here I get that to happen by reading ALL of memory.
1952 // A better answer would be to separate out card marks from other memory.
1953 // For now, return the input memory state, so that it can be reused
1954 // after the call, if this call has restricted memory effects.
1955 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call, Node* narrow_mem) {
1956   // Set fixed predefined input arguments
1957   call->init_req(TypeFunc::Control, control());
1958   call->init_req(TypeFunc::I_O, top()); // does no i/o
1959   call->init_req(TypeFunc::ReturnAdr, top());
1960   if (call->is_CallLeafPure()) {
1961     call->init_req(TypeFunc::Memory, top());
1962     call->init_req(TypeFunc::FramePtr, top());
1963     return nullptr;
1964   } else {
1965     Node* memory = reset_memory();
1966     Node* m = narrow_mem == nullptr ? memory : narrow_mem;
1967     call->init_req(TypeFunc::Memory, m); // may gc ptrs
1968     call->init_req(TypeFunc::FramePtr, frameptr());
1969     return memory;
1970   }
1971 }
1972 
1973 //-------------------set_predefined_output_for_runtime_call--------------------
1974 // Set control and memory (not i_o) from the call.
1975 // If keep_mem is not null, use it for the output state,
1976 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1977 // If hook_mem is null, this call produces no memory effects at all.
1978 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1979 // then only that memory slice is taken from the call.
1980 // In the last case, we must put an appropriate memory barrier before
1981 // the call, so as to create the correct anti-dependencies on loads
1982 // preceding the call.
1983 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1984                                                       Node* keep_mem,
1985                                                       const TypePtr* hook_mem) {
1986   // no i/o
1987   set_control(_gvn.transform( new ProjNode(call,TypeFunc::Control) ));
1988   if (call->is_CallLeafPure()) {
1989     // Pure function have only control (for now) and data output, in particular
1990     // they don't touch the memory, so we don't want a memory proj that is set after.
1991     return;
1992   }
1993   if (keep_mem) {
1994     // First clone the existing memory state
1995     set_all_memory(keep_mem);
1996     if (hook_mem != nullptr) {
1997       // Make memory for the call
1998       Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
1999       // Set the RawPtr memory state only.  This covers all the heap top/GC stuff
2000       // We also use hook_mem to extract specific effects from arraycopy stubs.
2001       set_memory(mem, hook_mem);
2002     }
2003     // ...else the call has NO memory effects.
2004 
2005     // Make sure the call advertises its memory effects precisely.
2006     // This lets us build accurate anti-dependences in gcm.cpp.
2007     assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
2008            "call node must be constructed correctly");
2009   } else {
2010     assert(hook_mem == nullptr, "");
2011     // This is not a "slow path" call; all memory comes from the call.
2012     set_all_memory_call(call);
2013   }
2014 }
2015 
2016 // Keep track of MergeMems feeding into other MergeMems
2017 static void add_mergemem_users_to_worklist(Unique_Node_List& wl, Node* mem) {
2018   if (!mem->is_MergeMem()) {
2019     return;
2020   }
2021   for (SimpleDUIterator i(mem); i.has_next(); i.next()) {
2022     Node* use = i.get();
2023     if (use->is_MergeMem()) {
2024       wl.push(use);
2025     }
2026   }
2027 }
2028 
2029 // Replace the call with the current state of the kit.
2030 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes, bool do_asserts) {
2031   JVMState* ejvms = nullptr;
2032   if (has_exceptions()) {
2033     ejvms = transfer_exceptions_into_jvms();
2034   }
2035 
2036   ReplacedNodes replaced_nodes = map()->replaced_nodes();
2037   ReplacedNodes replaced_nodes_exception;
2038   Node* ex_ctl = top();
2039 
2040   SafePointNode* final_state = stop();
2041 
2042   // Find all the needed outputs of this call
2043   CallProjections callprojs;
2044   call->extract_projections(&callprojs, true, do_asserts);
2045 
2046   Unique_Node_List wl;
2047   Node* init_mem = call->in(TypeFunc::Memory);
2048   Node* final_mem = final_state->in(TypeFunc::Memory);
2049   Node* final_ctl = final_state->in(TypeFunc::Control);
2050   Node* final_io = final_state->in(TypeFunc::I_O);
2051 
2052   // Replace all the old call edges with the edges from the inlining result
2053   if (callprojs.fallthrough_catchproj != nullptr) {
2054     C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
2055   }
2056   if (callprojs.fallthrough_memproj != nullptr) {
2057     if (final_mem->is_MergeMem()) {
2058       // Parser's exits MergeMem was not transformed but may be optimized
2059       final_mem = _gvn.transform(final_mem);
2060     }
2061     C->gvn_replace_by(callprojs.fallthrough_memproj,   final_mem);
2062     add_mergemem_users_to_worklist(wl, final_mem);
2063   }
2064   if (callprojs.fallthrough_ioproj != nullptr) {
2065     C->gvn_replace_by(callprojs.fallthrough_ioproj,    final_io);
2066   }
2067 
2068   // Replace the result with the new result if it exists and is used
2069   if (callprojs.resproj != nullptr && result != nullptr) {
2070     C->gvn_replace_by(callprojs.resproj, result);
2071   }
2072 
2073   if (ejvms == nullptr) {
2074     // No exception edges to simply kill off those paths
2075     if (callprojs.catchall_catchproj != nullptr) {
2076       C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
2077     }
2078     if (callprojs.catchall_memproj != nullptr) {
2079       C->gvn_replace_by(callprojs.catchall_memproj,   C->top());
2080     }
2081     if (callprojs.catchall_ioproj != nullptr) {
2082       C->gvn_replace_by(callprojs.catchall_ioproj,    C->top());
2083     }
2084     // Replace the old exception object with top
2085     if (callprojs.exobj != nullptr) {
2086       C->gvn_replace_by(callprojs.exobj, C->top());
2087     }
2088   } else {
2089     GraphKit ekit(ejvms);
2090 
2091     // Load my combined exception state into the kit, with all phis transformed:
2092     SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
2093     replaced_nodes_exception = ex_map->replaced_nodes();
2094 
2095     Node* ex_oop = ekit.use_exception_state(ex_map);
2096 
2097     if (callprojs.catchall_catchproj != nullptr) {
2098       C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
2099       ex_ctl = ekit.control();
2100     }
2101     if (callprojs.catchall_memproj != nullptr) {
2102       Node* ex_mem = ekit.reset_memory();
2103       C->gvn_replace_by(callprojs.catchall_memproj,   ex_mem);
2104       add_mergemem_users_to_worklist(wl, ex_mem);
2105     }
2106     if (callprojs.catchall_ioproj != nullptr) {
2107       C->gvn_replace_by(callprojs.catchall_ioproj,    ekit.i_o());
2108     }
2109 
2110     // Replace the old exception object with the newly created one
2111     if (callprojs.exobj != nullptr) {
2112       C->gvn_replace_by(callprojs.exobj, ex_oop);
2113     }
2114   }
2115 
2116   // Disconnect the call from the graph
2117   call->disconnect_inputs(C);
2118   C->gvn_replace_by(call, C->top());
2119 
2120   // Clean up any MergeMems that feed other MergeMems since the
2121   // optimizer doesn't like that.
2122   while (wl.size() > 0) {
2123     _gvn.transform(wl.pop());
2124   }
2125 
2126   if (callprojs.fallthrough_catchproj != nullptr && !final_ctl->is_top() && do_replaced_nodes) {
2127     replaced_nodes.apply(C, final_ctl);
2128   }
2129   if (!ex_ctl->is_top() && do_replaced_nodes) {
2130     replaced_nodes_exception.apply(C, ex_ctl);
2131   }
2132 }
2133 
2134 
2135 //------------------------------increment_counter------------------------------
2136 // for statistics: increment a VM counter by 1
2137 
2138 void GraphKit::increment_counter(address counter_addr) {
2139   Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
2140   increment_counter(adr1);
2141 }
2142 
2143 void GraphKit::increment_counter(Node* counter_addr) {
2144   Node* ctrl = control();
2145   Node* cnt  = make_load(ctrl, counter_addr, TypeLong::LONG, T_LONG, MemNode::unordered);
2146   Node* incr = _gvn.transform(new AddLNode(cnt, _gvn.longcon(1)));
2147   store_to_memory(ctrl, counter_addr, incr, T_LONG, MemNode::unordered);
2148 }
2149 
2150 void GraphKit::halt(Node* ctrl, Node* frameptr, const char* reason, bool generate_code_in_product) {
2151   Node* halt = new HaltNode(ctrl, frameptr, reason
2152                             PRODUCT_ONLY(COMMA generate_code_in_product));
2153   halt = _gvn.transform(halt);
2154   root()->add_req(halt);
2155 }
2156 
2157 //------------------------------uncommon_trap----------------------------------
2158 // Bail out to the interpreter in mid-method.  Implemented by calling the
2159 // uncommon_trap blob.  This helper function inserts a runtime call with the
2160 // right debug info.
2161 Node* GraphKit::uncommon_trap(int trap_request,
2162                              ciKlass* klass, const char* comment,
2163                              bool must_throw,
2164                              bool keep_exact_action) {
2165   if (failing_internal()) {
2166     stop();
2167   }
2168   if (stopped())  return nullptr; // trap reachable?
2169 
2170   // Note:  If ProfileTraps is true, and if a deopt. actually
2171   // occurs here, the runtime will make sure an MDO exists.  There is
2172   // no need to call method()->ensure_method_data() at this point.
2173 
2174   // Set the stack pointer to the right value for reexecution:
2175   set_sp(reexecute_sp());
2176 
2177 #ifdef ASSERT
2178   if (!must_throw) {
2179     // Make sure the stack has at least enough depth to execute
2180     // the current bytecode.
2181     int inputs, ignored_depth;
2182     if (compute_stack_effects(inputs, ignored_depth)) {
2183       assert(sp() >= inputs, "must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
2184              Bytecodes::name(java_bc()), sp(), inputs);
2185     }
2186   }
2187 #endif
2188 
2189   Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
2190   Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
2191 
2192   switch (action) {
2193   case Deoptimization::Action_maybe_recompile:
2194   case Deoptimization::Action_reinterpret:
2195     // Temporary fix for 6529811 to allow virtual calls to be sure they
2196     // get the chance to go from mono->bi->mega
2197     if (!keep_exact_action &&
2198         Deoptimization::trap_request_index(trap_request) < 0 &&
2199         too_many_recompiles(reason)) {
2200       // This BCI is causing too many recompilations.
2201       if (C->log() != nullptr) {
2202         C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'",
2203                 Deoptimization::trap_reason_name(reason),
2204                 Deoptimization::trap_action_name(action));
2205       }
2206       action = Deoptimization::Action_none;
2207       trap_request = Deoptimization::make_trap_request(reason, action);
2208     } else {
2209       C->set_trap_can_recompile(true);
2210     }
2211     break;
2212   case Deoptimization::Action_make_not_entrant:
2213     C->set_trap_can_recompile(true);
2214     break;
2215   case Deoptimization::Action_none:
2216   case Deoptimization::Action_make_not_compilable:
2217     break;
2218   default:
2219 #ifdef ASSERT
2220     fatal("unknown action %d: %s", action, Deoptimization::trap_action_name(action));
2221 #endif
2222     break;
2223   }
2224 
2225   if (TraceOptoParse) {
2226     char buf[100];
2227     tty->print_cr("Uncommon trap %s at bci:%d",
2228                   Deoptimization::format_trap_request(buf, sizeof(buf),
2229                                                       trap_request), bci());
2230   }
2231 
2232   if (PreloadReduceTraps && Compile::current()->for_preload() &&
2233       (action != Deoptimization::Action_none)) {
2234     ResourceMark rm;
2235     ciMethod* cim = Compile::current()->method();
2236     log_debug(aot, codecache, deoptimization)("Uncommon trap in preload code: reason=%s action=%s method=%s::%s bci=%d, %s",
2237                   Deoptimization::trap_reason_name(reason), Deoptimization::trap_action_name(action),
2238                   cim->holder()->name()->as_klass_external_name(), cim->name()->as_klass_external_name(),
2239                   bci(), comment);
2240   }
2241 
2242   CompileLog* log = C->log();
2243   if (log != nullptr) {
2244     int kid = (klass == nullptr)? -1: log->identify(klass);
2245     log->begin_elem("uncommon_trap bci='%d'", bci());
2246     char buf[100];
2247     log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2248                                                           trap_request));
2249     if (kid >= 0)         log->print(" klass='%d'", kid);
2250     if (comment != nullptr)  log->print(" comment='%s'", comment);
2251     log->end_elem();
2252   }
2253 
2254   // Make sure any guarding test views this path as very unlikely
2255   Node *i0 = control()->in(0);
2256   if (i0 != nullptr && i0->is_If()) {        // Found a guarding if test?
2257     IfNode *iff = i0->as_If();
2258     float f = iff->_prob;   // Get prob
2259     if (control()->Opcode() == Op_IfTrue) {
2260       if (f > PROB_UNLIKELY_MAG(4))
2261         iff->_prob = PROB_MIN;
2262     } else {
2263       if (f < PROB_LIKELY_MAG(4))
2264         iff->_prob = PROB_MAX;
2265     }
2266   }
2267 
2268   // Clear out dead values from the debug info.
2269   kill_dead_locals();
2270 
2271   // Now insert the uncommon trap subroutine call
2272   address call_addr = OptoRuntime::uncommon_trap_blob()->entry_point();
2273   const TypePtr* no_memory_effects = nullptr;
2274   // Pass the index of the class to be loaded
2275   Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2276                                  (must_throw ? RC_MUST_THROW : 0),
2277                                  OptoRuntime::uncommon_trap_Type(),
2278                                  call_addr, "uncommon_trap", no_memory_effects,
2279                                  intcon(trap_request));
2280   assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2281          "must extract request correctly from the graph");
2282   assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2283 
2284   call->set_req(TypeFunc::ReturnAdr, returnadr());
2285   // The debug info is the only real input to this call.
2286 
2287   // Halt-and-catch fire here.  The above call should never return!
2288   // We only emit code for the HaltNode in debug, which is enough for
2289   // verifying correctness. In product, we don't want to emit it so
2290   // that we can save on code space. HaltNode often get folded because
2291   // the compiler can prove that the unreachable path is dead. But we
2292   // cannot generally expect that for uncommon traps, which are often
2293   // reachable and occasionally taken.
2294   halt(control(), frameptr(),
2295        "uncommon trap returned which should never happen",
2296        false /* don't emit code in product */);
2297   stop_and_kill_map();
2298   return call;
2299 }
2300 
2301 
2302 //--------------------------just_allocated_object------------------------------
2303 // Report the object that was just allocated.
2304 // It must be the case that there are no intervening safepoints.
2305 // We use this to determine if an object is so "fresh" that
2306 // it does not require card marks.
2307 Node* GraphKit::just_allocated_object(Node* current_control) {
2308   Node* ctrl = current_control;
2309   // Object::<init> is invoked after allocation, most of invoke nodes
2310   // will be reduced, but a region node is kept in parse time, we check
2311   // the pattern and skip the region node if it degraded to a copy.
2312   if (ctrl != nullptr && ctrl->is_Region() && ctrl->req() == 2 &&
2313       ctrl->as_Region()->is_copy()) {
2314     ctrl = ctrl->as_Region()->is_copy();
2315   }
2316   if (C->recent_alloc_ctl() == ctrl) {
2317    return C->recent_alloc_obj();
2318   }
2319   return nullptr;
2320 }
2321 
2322 
2323 /**
2324  * Record profiling data exact_kls for Node n with the type system so
2325  * that it can propagate it (speculation)
2326  *
2327  * @param n          node that the type applies to
2328  * @param exact_kls  type from profiling
2329  * @param maybe_null did profiling see null?
2330  *
2331  * @return           node with improved type
2332  */
2333 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind) {
2334   const Type* current_type = _gvn.type(n);
2335   assert(UseTypeSpeculation, "type speculation must be on");
2336 
2337   const TypePtr* speculative = current_type->speculative();
2338 
2339   // Should the klass from the profile be recorded in the speculative type?
2340   if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2341     const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls, Type::trust_interfaces);
2342     const TypeOopPtr* xtype = tklass->as_instance_type();
2343     assert(xtype->klass_is_exact(), "Should be exact");
2344     // Any reason to believe n is not null (from this profiling or a previous one)?
2345     assert(ptr_kind != ProfileAlwaysNull, "impossible here");
2346     const TypePtr* ptr = (ptr_kind == ProfileMaybeNull && current_type->speculative_maybe_null()) ? TypePtr::BOTTOM : TypePtr::NOTNULL;
2347     // record the new speculative type's depth
2348     speculative = xtype->cast_to_ptr_type(ptr->ptr())->is_ptr();
2349     speculative = speculative->with_inline_depth(jvms()->depth());
2350   } else if (current_type->would_improve_ptr(ptr_kind)) {
2351     // Profiling report that null was never seen so we can change the
2352     // speculative type to non null ptr.
2353     if (ptr_kind == ProfileAlwaysNull) {
2354       speculative = TypePtr::NULL_PTR;
2355     } else {
2356       assert(ptr_kind == ProfileNeverNull, "nothing else is an improvement");
2357       const TypePtr* ptr = TypePtr::NOTNULL;
2358       if (speculative != nullptr) {
2359         speculative = speculative->cast_to_ptr_type(ptr->ptr())->is_ptr();
2360       } else {
2361         speculative = ptr;
2362       }
2363     }
2364   }
2365 
2366   if (speculative != current_type->speculative()) {
2367     // Build a type with a speculative type (what we think we know
2368     // about the type but will need a guard when we use it)
2369     const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2370     // We're changing the type, we need a new CheckCast node to carry
2371     // the new type. The new type depends on the control: what
2372     // profiling tells us is only valid from here as far as we can
2373     // tell.
2374     Node* cast = new CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2375     cast = _gvn.transform(cast);
2376     replace_in_map(n, cast);
2377     n = cast;
2378   }
2379 
2380   return n;
2381 }
2382 
2383 /**
2384  * Record profiling data from receiver profiling at an invoke with the
2385  * type system so that it can propagate it (speculation)
2386  *
2387  * @param n  receiver node
2388  *
2389  * @return   node with improved type
2390  */
2391 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2392   if (!UseTypeSpeculation) {
2393     return n;
2394   }
2395   ciKlass* exact_kls = profile_has_unique_klass();
2396   ProfilePtrKind ptr_kind = ProfileMaybeNull;
2397   if ((java_bc() == Bytecodes::_checkcast ||
2398        java_bc() == Bytecodes::_instanceof ||
2399        java_bc() == Bytecodes::_aastore) &&
2400       method()->method_data()->is_mature()) {
2401     ciProfileData* data = method()->method_data()->bci_to_data(bci());
2402     if (data != nullptr) {
2403       if (!data->as_BitData()->null_seen()) {
2404         ptr_kind = ProfileNeverNull;
2405       } else {
2406         if (TypeProfileCasts) {
2407           assert(data->is_ReceiverTypeData(), "bad profile data type");
2408           ciReceiverTypeData* call = (ciReceiverTypeData*)data->as_ReceiverTypeData();
2409           uint i = 0;
2410           for (; i < call->row_limit(); i++) {
2411             ciKlass* receiver = call->receiver(i);
2412             if (receiver != nullptr) {
2413               break;
2414             }
2415           }
2416           ptr_kind = (i == call->row_limit()) ? ProfileAlwaysNull : ProfileMaybeNull;
2417         }
2418       }
2419     }
2420   }
2421   return record_profile_for_speculation(n, exact_kls, ptr_kind);
2422 }
2423 
2424 /**
2425  * Record profiling data from argument profiling at an invoke with the
2426  * type system so that it can propagate it (speculation)
2427  *
2428  * @param dest_method  target method for the call
2429  * @param bc           what invoke bytecode is this?
2430  */
2431 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2432   if (!UseTypeSpeculation) {
2433     return;
2434   }
2435   const TypeFunc* tf    = TypeFunc::make(dest_method);
2436   int             nargs = tf->domain()->cnt() - TypeFunc::Parms;
2437   int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2438   for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2439     const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2440     if (is_reference_type(targ->basic_type())) {
2441       ProfilePtrKind ptr_kind = ProfileMaybeNull;
2442       ciKlass* better_type = nullptr;
2443       if (method()->argument_profiled_type(bci(), i, better_type, ptr_kind)) {
2444         record_profile_for_speculation(argument(j), better_type, ptr_kind);
2445       }
2446       i++;
2447     }
2448   }
2449 }
2450 
2451 /**
2452  * Record profiling data from parameter profiling at an invoke with
2453  * the type system so that it can propagate it (speculation)
2454  */
2455 void GraphKit::record_profiled_parameters_for_speculation() {
2456   if (!UseTypeSpeculation) {
2457     return;
2458   }
2459   for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2460     if (_gvn.type(local(i))->isa_oopptr()) {
2461       ProfilePtrKind ptr_kind = ProfileMaybeNull;
2462       ciKlass* better_type = nullptr;
2463       if (method()->parameter_profiled_type(j, better_type, ptr_kind)) {
2464         record_profile_for_speculation(local(i), better_type, ptr_kind);
2465       }
2466       j++;
2467     }
2468   }
2469 }
2470 
2471 /**
2472  * Record profiling data from return value profiling at an invoke with
2473  * the type system so that it can propagate it (speculation)
2474  */
2475 void GraphKit::record_profiled_return_for_speculation() {
2476   if (!UseTypeSpeculation) {
2477     return;
2478   }
2479   ProfilePtrKind ptr_kind = ProfileMaybeNull;
2480   ciKlass* better_type = nullptr;
2481   if (method()->return_profiled_type(bci(), better_type, ptr_kind)) {
2482     // If profiling reports a single type for the return value,
2483     // feed it to the type system so it can propagate it as a
2484     // speculative type
2485     record_profile_for_speculation(stack(sp()-1), better_type, ptr_kind);
2486   }
2487 }
2488 
2489 
2490 //=============================================================================
2491 // Generate a fast path/slow path idiom.  Graph looks like:
2492 // [foo] indicates that 'foo' is a parameter
2493 //
2494 //              [in]     null
2495 //                 \    /
2496 //                  CmpP
2497 //                  Bool ne
2498 //                   If
2499 //                  /  \
2500 //              True    False-<2>
2501 //              / |
2502 //             /  cast_not_null
2503 //           Load  |    |   ^
2504 //        [fast_test]   |   |
2505 // gvn to   opt_test    |   |
2506 //          /    \      |  <1>
2507 //      True     False  |
2508 //        |         \\  |
2509 //   [slow_call]     \[fast_result]
2510 //    Ctl   Val       \      \
2511 //     |               \      \
2512 //    Catch       <1>   \      \
2513 //   /    \        ^     \      \
2514 //  Ex    No_Ex    |      \      \
2515 //  |       \   \  |       \ <2>  \
2516 //  ...      \  [slow_res] |  |    \   [null_result]
2517 //            \         \--+--+---  |  |
2518 //             \           | /    \ | /
2519 //              --------Region     Phi
2520 //
2521 //=============================================================================
2522 // Code is structured as a series of driver functions all called 'do_XXX' that
2523 // call a set of helper functions.  Helper functions first, then drivers.
2524 
2525 //------------------------------null_check_oop---------------------------------
2526 // Null check oop.  Set null-path control into Region in slot 3.
2527 // Make a cast-not-nullness use the other not-null control.  Return cast.
2528 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2529                                bool never_see_null,
2530                                bool safe_for_replace,
2531                                bool speculative) {
2532   // Initial null check taken path
2533   (*null_control) = top();
2534   Node* cast = null_check_common(value, T_OBJECT, false, null_control, speculative);
2535 
2536   // Generate uncommon_trap:
2537   if (never_see_null && (*null_control) != top()) {
2538     // If we see an unexpected null at a check-cast we record it and force a
2539     // recompile; the offending check-cast will be compiled to handle nulls.
2540     // If we see more than one offending BCI, then all checkcasts in the
2541     // method will be compiled to handle nulls.
2542     PreserveJVMState pjvms(this);
2543     set_control(*null_control);
2544     replace_in_map(value, null());
2545     Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculative);
2546     uncommon_trap(reason,
2547                   Deoptimization::Action_make_not_entrant);
2548     (*null_control) = top();    // null path is dead
2549   }
2550   if ((*null_control) == top() && safe_for_replace) {
2551     replace_in_map(value, cast);
2552   }
2553 
2554   // Cast away null-ness on the result
2555   return cast;
2556 }
2557 
2558 //------------------------------opt_iff----------------------------------------
2559 // Optimize the fast-check IfNode.  Set the fast-path region slot 2.
2560 // Return slow-path control.
2561 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2562   IfNode *opt_iff = _gvn.transform(iff)->as_If();
2563 
2564   // Fast path taken; set region slot 2
2565   Node *fast_taken = _gvn.transform( new IfFalseNode(opt_iff) );
2566   region->init_req(2,fast_taken); // Capture fast-control
2567 
2568   // Fast path not-taken, i.e. slow path
2569   Node *slow_taken = _gvn.transform( new IfTrueNode(opt_iff) );
2570   return slow_taken;
2571 }
2572 
2573 //-----------------------------make_runtime_call-------------------------------
2574 Node* GraphKit::make_runtime_call(int flags,
2575                                   const TypeFunc* call_type, address call_addr,
2576                                   const char* call_name,
2577                                   const TypePtr* adr_type,
2578                                   // The following parms are all optional.
2579                                   // The first null ends the list.
2580                                   Node* parm0, Node* parm1,
2581                                   Node* parm2, Node* parm3,
2582                                   Node* parm4, Node* parm5,
2583                                   Node* parm6, Node* parm7) {
2584   assert(call_addr != nullptr, "must not call null targets");
2585 
2586   // Slow-path call
2587   bool is_leaf = !(flags & RC_NO_LEAF);
2588   bool has_io  = (!is_leaf && !(flags & RC_NO_IO));
2589   if (call_name == nullptr) {
2590     assert(!is_leaf, "must supply name for leaf");
2591     call_name = OptoRuntime::stub_name(call_addr);
2592   }
2593   CallNode* call;
2594   if (!is_leaf) {
2595     call = new CallStaticJavaNode(call_type, call_addr, call_name, adr_type);
2596   } else if (flags & RC_NO_FP) {
2597     call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2598   } else  if (flags & RC_VECTOR){
2599     uint num_bits = call_type->range()->field_at(TypeFunc::Parms)->is_vect()->length_in_bytes() * BitsPerByte;
2600     call = new CallLeafVectorNode(call_type, call_addr, call_name, adr_type, num_bits);
2601   } else if (flags & RC_PURE) {
2602     assert(adr_type == nullptr, "pure call does not touch memory");
2603     call = new CallLeafPureNode(call_type, call_addr, call_name);
2604   } else {
2605     call = new CallLeafNode(call_type, call_addr, call_name, adr_type);
2606   }
2607 
2608   // The following is similar to set_edges_for_java_call,
2609   // except that the memory effects of the call are restricted to AliasIdxRaw.
2610 
2611   // Slow path call has no side-effects, uses few values
2612   bool wide_in  = !(flags & RC_NARROW_MEM);
2613   bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2614 
2615   Node* prev_mem = nullptr;
2616   if (wide_in) {
2617     prev_mem = set_predefined_input_for_runtime_call(call);
2618   } else {
2619     assert(!wide_out, "narrow in => narrow out");
2620     Node* narrow_mem = memory(adr_type);
2621     prev_mem = set_predefined_input_for_runtime_call(call, narrow_mem);
2622   }
2623 
2624   // Hook each parm in order.  Stop looking at the first null.
2625   if (parm0 != nullptr) { call->init_req(TypeFunc::Parms+0, parm0);
2626   if (parm1 != nullptr) { call->init_req(TypeFunc::Parms+1, parm1);
2627   if (parm2 != nullptr) { call->init_req(TypeFunc::Parms+2, parm2);
2628   if (parm3 != nullptr) { call->init_req(TypeFunc::Parms+3, parm3);
2629   if (parm4 != nullptr) { call->init_req(TypeFunc::Parms+4, parm4);
2630   if (parm5 != nullptr) { call->init_req(TypeFunc::Parms+5, parm5);
2631   if (parm6 != nullptr) { call->init_req(TypeFunc::Parms+6, parm6);
2632   if (parm7 != nullptr) { call->init_req(TypeFunc::Parms+7, parm7);
2633   /* close each nested if ===> */  } } } } } } } }
2634   assert(call->in(call->req()-1) != nullptr, "must initialize all parms");
2635 
2636   if (!is_leaf) {
2637     // Non-leaves can block and take safepoints:
2638     add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2639   }
2640   // Non-leaves can throw exceptions:
2641   if (has_io) {
2642     call->set_req(TypeFunc::I_O, i_o());
2643   }
2644 
2645   if (flags & RC_UNCOMMON) {
2646     // Set the count to a tiny probability.  Cf. Estimate_Block_Frequency.
2647     // (An "if" probability corresponds roughly to an unconditional count.
2648     // Sort of.)
2649     call->set_cnt(PROB_UNLIKELY_MAG(4));
2650   }
2651 
2652   Node* c = _gvn.transform(call);
2653   assert(c == call, "cannot disappear");
2654 
2655   if (wide_out) {
2656     // Slow path call has full side-effects.
2657     set_predefined_output_for_runtime_call(call);
2658   } else {
2659     // Slow path call has few side-effects, and/or sets few values.
2660     set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2661   }
2662 
2663   if (has_io) {
2664     set_i_o(_gvn.transform(new ProjNode(call, TypeFunc::I_O)));
2665   }
2666   return call;
2667 
2668 }
2669 
2670 // i2b
2671 Node* GraphKit::sign_extend_byte(Node* in) {
2672   Node* tmp = _gvn.transform(new LShiftINode(in, _gvn.intcon(24)));
2673   return _gvn.transform(new RShiftINode(tmp, _gvn.intcon(24)));
2674 }
2675 
2676 // i2s
2677 Node* GraphKit::sign_extend_short(Node* in) {
2678   Node* tmp = _gvn.transform(new LShiftINode(in, _gvn.intcon(16)));
2679   return _gvn.transform(new RShiftINode(tmp, _gvn.intcon(16)));
2680 }
2681 
2682 //------------------------------merge_memory-----------------------------------
2683 // Merge memory from one path into the current memory state.
2684 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2685   for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2686     Node* old_slice = mms.force_memory();
2687     Node* new_slice = mms.memory2();
2688     if (old_slice != new_slice) {
2689       PhiNode* phi;
2690       if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) {
2691         if (mms.is_empty()) {
2692           // clone base memory Phi's inputs for this memory slice
2693           assert(old_slice == mms.base_memory(), "sanity");
2694           phi = PhiNode::make(region, nullptr, Type::MEMORY, mms.adr_type(C));
2695           _gvn.set_type(phi, Type::MEMORY);
2696           for (uint i = 1; i < phi->req(); i++) {
2697             phi->init_req(i, old_slice->in(i));
2698           }
2699         } else {
2700           phi = old_slice->as_Phi(); // Phi was generated already
2701         }
2702       } else {
2703         phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2704         _gvn.set_type(phi, Type::MEMORY);
2705       }
2706       phi->set_req(new_path, new_slice);
2707       mms.set_memory(phi);
2708     }
2709   }
2710 }
2711 
2712 //------------------------------make_slow_call_ex------------------------------
2713 // Make the exception handler hookups for the slow call
2714 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) {
2715   if (stopped())  return;
2716 
2717   // Make a catch node with just two handlers:  fall-through and catch-all
2718   Node* i_o  = _gvn.transform( new ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2719   Node* catc = _gvn.transform( new CatchNode(control(), i_o, 2) );
2720   Node* norm = new CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci);
2721   _gvn.set_type_bottom(norm);
2722   C->record_for_igvn(norm);
2723   Node* excp = _gvn.transform( new CatchProjNode(catc, CatchProjNode::catch_all_index,    CatchProjNode::no_handler_bci) );
2724 
2725   { PreserveJVMState pjvms(this);
2726     set_control(excp);
2727     set_i_o(i_o);
2728 
2729     if (excp != top()) {
2730       if (deoptimize) {
2731         // Deoptimize if an exception is caught. Don't construct exception state in this case.
2732         uncommon_trap(Deoptimization::Reason_unhandled,
2733                       Deoptimization::Action_none);
2734       } else {
2735         // Create an exception state also.
2736         // Use an exact type if the caller has a specific exception.
2737         const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2738         Node*       ex_oop  = new CreateExNode(ex_type, control(), i_o);
2739         add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2740       }
2741     }
2742   }
2743 
2744   // Get the no-exception control from the CatchNode.
2745   set_control(norm);
2746 }
2747 
2748 static IfNode* gen_subtype_check_compare(Node* ctrl, Node* in1, Node* in2, BoolTest::mask test, float p, PhaseGVN& gvn, BasicType bt) {
2749   Node* cmp = nullptr;
2750   switch(bt) {
2751   case T_INT: cmp = new CmpINode(in1, in2); break;
2752   case T_ADDRESS: cmp = new CmpPNode(in1, in2); break;
2753   default: fatal("unexpected comparison type %s", type2name(bt));
2754   }
2755   cmp = gvn.transform(cmp);
2756   Node* bol = gvn.transform(new BoolNode(cmp, test));
2757   IfNode* iff = new IfNode(ctrl, bol, p, COUNT_UNKNOWN);
2758   gvn.transform(iff);
2759   if (!bol->is_Con()) gvn.record_for_igvn(iff);
2760   return iff;
2761 }
2762 
2763 //-------------------------------gen_subtype_check-----------------------------
2764 // Generate a subtyping check.  Takes as input the subtype and supertype.
2765 // Returns 2 values: sets the default control() to the true path and returns
2766 // the false path.  Only reads invariant memory; sets no (visible) memory.
2767 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2768 // but that's not exposed to the optimizer.  This call also doesn't take in an
2769 // Object; if you wish to check an Object you need to load the Object's class
2770 // prior to coming here.
2771 Node* Phase::gen_subtype_check(Node* subklass, Node* superklass, Node** ctrl, Node* mem, PhaseGVN& gvn,
2772                                ciMethod* method, int bci) {
2773   Compile* C = gvn.C;
2774   if ((*ctrl)->is_top()) {
2775     return C->top();
2776   }
2777 
2778   // Fast check for identical types, perhaps identical constants.
2779   // The types can even be identical non-constants, in cases
2780   // involving Array.newInstance, Object.clone, etc.
2781   if (subklass == superklass)
2782     return C->top();             // false path is dead; no test needed.
2783 
2784   if (gvn.type(superklass)->singleton()) {
2785     const TypeKlassPtr* superk = gvn.type(superklass)->is_klassptr();
2786     const TypeKlassPtr* subk   = gvn.type(subklass)->is_klassptr();
2787 
2788     // In the common case of an exact superklass, try to fold up the
2789     // test before generating code.  You may ask, why not just generate
2790     // the code and then let it fold up?  The answer is that the generated
2791     // code will necessarily include null checks, which do not always
2792     // completely fold away.  If they are also needless, then they turn
2793     // into a performance loss.  Example:
2794     //    Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2795     // Here, the type of 'fa' is often exact, so the store check
2796     // of fa[1]=x will fold up, without testing the nullness of x.
2797     //
2798     // At macro expansion, we would have already folded the SubTypeCheckNode
2799     // being expanded here because we always perform the static sub type
2800     // check in SubTypeCheckNode::sub() regardless of whether
2801     // StressReflectiveCode is set or not. We can therefore skip this
2802     // static check when StressReflectiveCode is on.
2803     switch (C->static_subtype_check(superk, subk)) {
2804     case Compile::SSC_always_false:
2805       {
2806         Node* always_fail = *ctrl;
2807         *ctrl = gvn.C->top();
2808         return always_fail;
2809       }
2810     case Compile::SSC_always_true:
2811       return C->top();
2812     case Compile::SSC_easy_test:
2813       {
2814         // Just do a direct pointer compare and be done.
2815         IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_STATIC_FREQUENT, gvn, T_ADDRESS);
2816         *ctrl = gvn.transform(new IfTrueNode(iff));
2817         return gvn.transform(new IfFalseNode(iff));
2818       }
2819     case Compile::SSC_full_test:
2820       break;
2821     default:
2822       ShouldNotReachHere();
2823     }
2824   }
2825 
2826   // %%% Possible further optimization:  Even if the superklass is not exact,
2827   // if the subklass is the unique subtype of the superklass, the check
2828   // will always succeed.  We could leave a dependency behind to ensure this.
2829 
2830   // First load the super-klass's check-offset
2831   Node *p1 = gvn.transform(new AddPNode(C->top(), superklass, gvn.MakeConX(in_bytes(Klass::super_check_offset_offset()))));
2832   Node* m = C->immutable_memory();
2833   Node *chk_off = gvn.transform(new LoadINode(nullptr, m, p1, gvn.type(p1)->is_ptr(), TypeInt::INT, MemNode::unordered));
2834   int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2835   const TypeInt* chk_off_t = chk_off->Value(&gvn)->isa_int();
2836   int chk_off_con = (chk_off_t != nullptr && chk_off_t->is_con()) ? chk_off_t->get_con() : cacheoff_con;
2837   bool might_be_cache = (chk_off_con == cacheoff_con);
2838 
2839   // Load from the sub-klass's super-class display list, or a 1-word cache of
2840   // the secondary superclass list, or a failing value with a sentinel offset
2841   // if the super-klass is an interface or exceptionally deep in the Java
2842   // hierarchy and we have to scan the secondary superclass list the hard way.
2843   // Worst-case type is a little odd: null is allowed as a result (usually
2844   // klass loads can never produce a null).
2845   Node *chk_off_X = chk_off;
2846 #ifdef _LP64
2847   chk_off_X = gvn.transform(new ConvI2LNode(chk_off_X));
2848 #endif
2849   Node* p2 = gvn.transform(new AddPNode(C->top(), subklass, chk_off_X));
2850   // For some types like interfaces the following loadKlass is from a 1-word
2851   // cache which is mutable so can't use immutable memory.  Other
2852   // types load from the super-class display table which is immutable.
2853   Node *kmem = C->immutable_memory();
2854   // secondary_super_cache is not immutable but can be treated as such because:
2855   // - no ideal node writes to it in a way that could cause an
2856   //   incorrect/missed optimization of the following Load.
2857   // - it's a cache so, worse case, not reading the latest value
2858   //   wouldn't cause incorrect execution
2859   if (might_be_cache && mem != nullptr) {
2860     kmem = mem->is_MergeMem() ? mem->as_MergeMem()->memory_at(C->get_alias_index(gvn.type(p2)->is_ptr())) : mem;
2861   }
2862   Node* nkls = gvn.transform(LoadKlassNode::make(gvn, kmem, p2, gvn.type(p2)->is_ptr(), TypeInstKlassPtr::OBJECT_OR_NULL));
2863 
2864   // Compile speed common case: ARE a subtype and we canNOT fail
2865   if (superklass == nkls) {
2866     return C->top();             // false path is dead; no test needed.
2867   }
2868 
2869   // Gather the various success & failures here
2870   RegionNode* r_not_subtype = new RegionNode(3);
2871   gvn.record_for_igvn(r_not_subtype);
2872   RegionNode* r_ok_subtype = new RegionNode(4);
2873   gvn.record_for_igvn(r_ok_subtype);
2874 
2875   // If we might perform an expensive check, first try to take advantage of profile data that was attached to the
2876   // SubTypeCheck node
2877   if (might_be_cache && method != nullptr && VM_Version::profile_all_receivers_at_type_check()) {
2878     ciCallProfile profile = method->call_profile_at_bci(bci);
2879     float total_prob = 0;
2880     for (int i = 0; profile.has_receiver(i); ++i) {
2881       float prob = profile.receiver_prob(i);
2882       total_prob += prob;
2883     }
2884     if (total_prob * 100. >= TypeProfileSubTypeCheckCommonThreshold) {
2885       const TypeKlassPtr* superk = gvn.type(superklass)->is_klassptr();
2886       for (int i = 0; profile.has_receiver(i); ++i) {
2887         ciKlass* klass = profile.receiver(i);
2888         const TypeKlassPtr* klass_t = TypeKlassPtr::make(klass);
2889         Compile::SubTypeCheckResult result = C->static_subtype_check(superk, klass_t);
2890         if (result != Compile::SSC_always_true && result != Compile::SSC_always_false) {
2891           continue;
2892         }
2893         float prob = profile.receiver_prob(i);
2894         ConNode* klass_node = gvn.makecon(klass_t);
2895         IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, klass_node, BoolTest::eq, prob, gvn, T_ADDRESS);
2896         Node* iftrue = gvn.transform(new IfTrueNode(iff));
2897 
2898         if (result == Compile::SSC_always_true) {
2899           r_ok_subtype->add_req(iftrue);
2900         } else {
2901           assert(result == Compile::SSC_always_false, "");
2902           r_not_subtype->add_req(iftrue);
2903         }
2904         *ctrl = gvn.transform(new IfFalseNode(iff));
2905       }
2906     }
2907   }
2908 
2909   // See if we get an immediate positive hit.  Happens roughly 83% of the
2910   // time.  Test to see if the value loaded just previously from the subklass
2911   // is exactly the superklass.
2912   IfNode *iff1 = gen_subtype_check_compare(*ctrl, superklass, nkls, BoolTest::eq, PROB_LIKELY(0.83f), gvn, T_ADDRESS);
2913   Node *iftrue1 = gvn.transform( new IfTrueNode (iff1));
2914   *ctrl = gvn.transform(new IfFalseNode(iff1));
2915 
2916   // Compile speed common case: Check for being deterministic right now.  If
2917   // chk_off is a constant and not equal to cacheoff then we are NOT a
2918   // subklass.  In this case we need exactly the 1 test above and we can
2919   // return those results immediately.
2920   if (!might_be_cache) {
2921     Node* not_subtype_ctrl = *ctrl;
2922     *ctrl = iftrue1; // We need exactly the 1 test above
2923     PhaseIterGVN* igvn = gvn.is_IterGVN();
2924     if (igvn != nullptr) {
2925       igvn->remove_globally_dead_node(r_ok_subtype);
2926       igvn->remove_globally_dead_node(r_not_subtype);
2927     }
2928     return not_subtype_ctrl;
2929   }
2930 
2931   r_ok_subtype->init_req(1, iftrue1);
2932 
2933   // Check for immediate negative hit.  Happens roughly 11% of the time (which
2934   // is roughly 63% of the remaining cases).  Test to see if the loaded
2935   // check-offset points into the subklass display list or the 1-element
2936   // cache.  If it points to the display (and NOT the cache) and the display
2937   // missed then it's not a subtype.
2938   Node *cacheoff = gvn.intcon(cacheoff_con);
2939   IfNode *iff2 = gen_subtype_check_compare(*ctrl, chk_off, cacheoff, BoolTest::ne, PROB_LIKELY(0.63f), gvn, T_INT);
2940   r_not_subtype->init_req(1, gvn.transform(new IfTrueNode (iff2)));
2941   *ctrl = gvn.transform(new IfFalseNode(iff2));
2942 
2943   // Check for self.  Very rare to get here, but it is taken 1/3 the time.
2944   // No performance impact (too rare) but allows sharing of secondary arrays
2945   // which has some footprint reduction.
2946   IfNode *iff3 = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_LIKELY(0.36f), gvn, T_ADDRESS);
2947   r_ok_subtype->init_req(2, gvn.transform(new IfTrueNode(iff3)));
2948   *ctrl = gvn.transform(new IfFalseNode(iff3));
2949 
2950   // -- Roads not taken here: --
2951   // We could also have chosen to perform the self-check at the beginning
2952   // of this code sequence, as the assembler does.  This would not pay off
2953   // the same way, since the optimizer, unlike the assembler, can perform
2954   // static type analysis to fold away many successful self-checks.
2955   // Non-foldable self checks work better here in second position, because
2956   // the initial primary superclass check subsumes a self-check for most
2957   // types.  An exception would be a secondary type like array-of-interface,
2958   // which does not appear in its own primary supertype display.
2959   // Finally, we could have chosen to move the self-check into the
2960   // PartialSubtypeCheckNode, and from there out-of-line in a platform
2961   // dependent manner.  But it is worthwhile to have the check here,
2962   // where it can be perhaps be optimized.  The cost in code space is
2963   // small (register compare, branch).
2964 
2965   // Now do a linear scan of the secondary super-klass array.  Again, no real
2966   // performance impact (too rare) but it's gotta be done.
2967   // Since the code is rarely used, there is no penalty for moving it
2968   // out of line, and it can only improve I-cache density.
2969   // The decision to inline or out-of-line this final check is platform
2970   // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2971   Node* psc = gvn.transform(
2972     new PartialSubtypeCheckNode(*ctrl, subklass, superklass));
2973 
2974   IfNode *iff4 = gen_subtype_check_compare(*ctrl, psc, gvn.zerocon(T_OBJECT), BoolTest::ne, PROB_FAIR, gvn, T_ADDRESS);
2975   r_not_subtype->init_req(2, gvn.transform(new IfTrueNode (iff4)));
2976   r_ok_subtype ->init_req(3, gvn.transform(new IfFalseNode(iff4)));
2977 
2978   // Return false path; set default control to true path.
2979   *ctrl = gvn.transform(r_ok_subtype);
2980   return gvn.transform(r_not_subtype);
2981 }
2982 
2983 Node* GraphKit::gen_subtype_check(Node* obj_or_subklass, Node* superklass) {
2984   bool expand_subtype_check = C->post_loop_opts_phase(); // macro node expansion is over
2985   if (expand_subtype_check) {
2986     MergeMemNode* mem = merged_memory();
2987     Node* ctrl = control();
2988     Node* subklass = obj_or_subklass;
2989     if (!_gvn.type(obj_or_subklass)->isa_klassptr()) {
2990       subklass = load_object_klass(obj_or_subklass);
2991     }
2992 
2993     Node* n = Phase::gen_subtype_check(subklass, superklass, &ctrl, mem, _gvn, method(), bci());
2994     set_control(ctrl);
2995     return n;
2996   }
2997 
2998   Node* check = _gvn.transform(new SubTypeCheckNode(C, obj_or_subklass, superklass, method(), bci()));
2999   Node* bol = _gvn.transform(new BoolNode(check, BoolTest::eq));
3000   IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN);
3001   set_control(_gvn.transform(new IfTrueNode(iff)));
3002   return _gvn.transform(new IfFalseNode(iff));
3003 }
3004 
3005 // Profile-driven exact type check:
3006 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
3007                                     float prob,
3008                                     Node* *casted_receiver) {
3009   assert(!klass->is_interface(), "no exact type check on interfaces");
3010 
3011   const TypeKlassPtr* tklass = TypeKlassPtr::make(klass, Type::trust_interfaces);
3012   Node* recv_klass = load_object_klass(receiver);
3013   Node* want_klass = makecon(tklass);
3014   Node* cmp = _gvn.transform(new CmpPNode(recv_klass, want_klass));
3015   Node* bol = _gvn.transform(new BoolNode(cmp, BoolTest::eq));
3016   IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
3017   set_control( _gvn.transform(new IfTrueNode (iff)));
3018   Node* fail = _gvn.transform(new IfFalseNode(iff));
3019 
3020   if (!stopped()) {
3021     const TypeOopPtr* receiver_type = _gvn.type(receiver)->isa_oopptr();
3022     const TypeOopPtr* recvx_type = tklass->as_instance_type();
3023     assert(recvx_type->klass_is_exact(), "");
3024 
3025     if (!receiver_type->higher_equal(recvx_type)) { // ignore redundant casts
3026       // Subsume downstream occurrences of receiver with a cast to
3027       // recv_xtype, since now we know what the type will be.
3028       Node* cast = new CheckCastPPNode(control(), receiver, recvx_type);
3029       (*casted_receiver) = _gvn.transform(cast);
3030       assert(!(*casted_receiver)->is_top(), "that path should be unreachable");
3031       // (User must make the replace_in_map call.)
3032     }
3033   }
3034 
3035   return fail;
3036 }
3037 
3038 //------------------------------subtype_check_receiver-------------------------
3039 Node* GraphKit::subtype_check_receiver(Node* receiver, ciKlass* klass,
3040                                        Node** casted_receiver) {
3041   const TypeKlassPtr* tklass = TypeKlassPtr::make(klass, Type::trust_interfaces)->try_improve();
3042   Node* want_klass = makecon(tklass);
3043 
3044   Node* slow_ctl = gen_subtype_check(receiver, want_klass);
3045 
3046   // Ignore interface type information until interface types are properly tracked.
3047   if (!stopped() && !klass->is_interface()) {
3048     const TypeOopPtr* receiver_type = _gvn.type(receiver)->isa_oopptr();
3049     const TypeOopPtr* recv_type = tklass->cast_to_exactness(false)->is_klassptr()->as_instance_type();
3050     if (!receiver_type->higher_equal(recv_type)) { // ignore redundant casts
3051       Node* cast = new CheckCastPPNode(control(), receiver, recv_type);
3052       (*casted_receiver) = _gvn.transform(cast);
3053     }
3054   }
3055 
3056   return slow_ctl;
3057 }
3058 
3059 //------------------------------seems_never_null-------------------------------
3060 // Use null_seen information if it is available from the profile.
3061 // If we see an unexpected null at a type check we record it and force a
3062 // recompile; the offending check will be recompiled to handle nulls.
3063 // If we see several offending BCIs, then all checks in the
3064 // method will be recompiled.
3065 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data, bool& speculating) {
3066   speculating = !_gvn.type(obj)->speculative_maybe_null();
3067   Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculating);
3068   if (UncommonNullCast               // Cutout for this technique
3069       && obj != null()               // And not the -Xcomp stupid case?
3070       && !too_many_traps(reason)
3071       ) {
3072     if (speculating) {
3073       return true;
3074     }
3075     if (data == nullptr)
3076       // Edge case:  no mature data.  Be optimistic here.
3077       return true;
3078     // If the profile has not seen a null, assume it won't happen.
3079     assert(java_bc() == Bytecodes::_checkcast ||
3080            java_bc() == Bytecodes::_instanceof ||
3081            java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
3082     return !data->as_BitData()->null_seen();
3083   }
3084   speculating = false;
3085   return false;
3086 }
3087 
3088 void GraphKit::guard_klass_is_initialized(Node* klass) {
3089   assert(C->do_clinit_barriers(), "should be called only for clinit barriers");
3090   int init_state_off = in_bytes(InstanceKlass::init_state_offset());
3091   Node* adr = basic_plus_adr(top(), klass, init_state_off);
3092   Node* init_state = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3093                                     adr->bottom_type()->is_ptr(), TypeInt::BYTE,
3094                                     T_BYTE, MemNode::unordered);
3095   init_state = _gvn.transform(init_state);
3096 
3097   Node* initialized_state = makecon(TypeInt::make(InstanceKlass::fully_initialized));
3098 
3099   Node* chk = _gvn.transform(new CmpINode(initialized_state, init_state));
3100   Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3101 
3102   switch (ClassInitBarrierMode) {
3103     case 1: { // uncommon trap on slow path
3104       BuildCutout unless(this, tst, PROB_MAX);
3105       // Do not deoptimize this nmethod. Go to Interpreter to initialize class.
3106       uncommon_trap(Deoptimization::Reason_uninitialized, Deoptimization::Action_none);
3107       break;
3108     }
3109     case 2: { // runtime call on slow path
3110       if (StressClassInitBarriers) {
3111         tst = makecon(TypeInt::ZERO); // always go through slow path
3112       }
3113       IfNode* iff = create_and_xform_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
3114 //    IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
3115 
3116       RegionNode* r = new RegionNode(3);
3117       r->init_req(1, _gvn.transform(new IfTrueNode(iff)));
3118 
3119       set_control(_gvn.transform(new IfFalseNode(iff)));
3120 
3121       if (!stopped()) {
3122         kill_dead_locals();
3123 
3124         Node* call = make_runtime_call(RC_NO_LEAF,
3125                                        OptoRuntime::class_init_barrier_Type(),
3126                                        OptoRuntime::class_init_barrier_Java(),
3127                                        nullptr, TypePtr::BOTTOM,
3128                                        klass);
3129         // Deoptimization during class init barrier execution should trigger current bytecode reexecution.
3130         call->jvms()->set_should_reexecute(true);
3131 
3132         // FIXME: deoptimize for now. deoptimize=false doesn't work with late inlining yet.
3133         // Parse::create_entry_map() introduces a barrier which uses distinct JVM state (*before* call).
3134         // Compilation fails when distinct exception states are combined.
3135         make_slow_call_ex(call, env()->Throwable_klass(), /*separate_io_proj=*/true, /*deoptimize=*/true);
3136 
3137         Node* fast_io  = call->in(TypeFunc::I_O);
3138         Node* fast_mem = call->in(TypeFunc::Memory);
3139         // These two phis are pre-filled with copies of of the fast IO and Memory
3140         Node* io_phi   = PhiNode::make(r, fast_io,  Type::ABIO);
3141         Node* mem_phi  = PhiNode::make(r, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
3142 
3143         r->init_req(2, control());
3144         io_phi->init_req(2, i_o());
3145         mem_phi->init_req(2, reset_memory());
3146 
3147         set_all_memory(_gvn.transform(mem_phi));
3148         set_i_o(_gvn.transform(io_phi));
3149       } else {
3150         r->init_req(2, top());
3151       }
3152       set_control(_gvn.transform(r));
3153       break;
3154     }
3155 
3156     default: fatal("unknown barrier mode: %d", ClassInitBarrierMode);
3157   }
3158   C->set_has_clinit_barriers(true);
3159 }
3160 
3161 void GraphKit::guard_klass_being_initialized(Node* klass) {
3162   int init_state_off = in_bytes(InstanceKlass::init_state_offset());
3163   Node* adr = basic_plus_adr(top(), klass, init_state_off);
3164   Node* init_state = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3165                                     adr->bottom_type()->is_ptr(), TypeInt::BYTE,
3166                                     T_BYTE, MemNode::acquire);
3167   init_state = _gvn.transform(init_state);
3168 
3169   Node* being_initialized_state = makecon(TypeInt::make(InstanceKlass::being_initialized));
3170 
3171   Node* chk = _gvn.transform(new CmpINode(being_initialized_state, init_state));
3172   Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3173 
3174   { BuildCutout unless(this, tst, PROB_MAX);
3175     uncommon_trap(Deoptimization::Reason_initialized, Deoptimization::Action_reinterpret);
3176   }
3177 }
3178 
3179 void GraphKit::guard_init_thread(Node* klass) {
3180   int init_thread_off = in_bytes(InstanceKlass::init_thread_offset());
3181   Node* adr = basic_plus_adr(top(), klass, init_thread_off);
3182 
3183   Node* init_thread = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3184                                      adr->bottom_type()->is_ptr(), TypePtr::NOTNULL,
3185                                      T_ADDRESS, MemNode::unordered);
3186   init_thread = _gvn.transform(init_thread);
3187 
3188   Node* cur_thread = _gvn.transform(new ThreadLocalNode());
3189 
3190   Node* chk = _gvn.transform(new CmpPNode(cur_thread, init_thread));
3191   Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3192 
3193   { BuildCutout unless(this, tst, PROB_MAX);
3194     uncommon_trap(Deoptimization::Reason_uninitialized, Deoptimization::Action_none);
3195   }
3196 }
3197 
3198 void GraphKit::clinit_barrier(ciInstanceKlass* ik, ciMethod* context) {
3199   if (C->do_clinit_barriers()) {
3200     Node* klass = makecon(TypeKlassPtr::make(ik, Type::trust_interfaces));
3201     guard_klass_is_initialized(klass);
3202     return;
3203   }
3204   if (ik->is_being_initialized()) {
3205     if (C->needs_clinit_barrier(ik, context)) {
3206       Node* klass = makecon(TypeKlassPtr::make(ik, Type::trust_interfaces));
3207       guard_klass_being_initialized(klass);
3208       guard_init_thread(klass);
3209       insert_mem_bar(Op_MemBarCPUOrder);
3210     }
3211   } else if (ik->is_initialized()) {
3212     return; // no barrier needed
3213   } else {
3214     if (C->env()->task()->is_aot_compile()) {
3215       ResourceMark rm;
3216       log_debug(aot, compilation)("Emitting uncommon trap (clinit barrier) in AOT code for %s", ik->name()->as_klass_external_name());
3217     }
3218     uncommon_trap(Deoptimization::Reason_uninitialized,
3219                   Deoptimization::Action_reinterpret,
3220                   nullptr);
3221   }
3222 }
3223 
3224 //------------------------maybe_cast_profiled_receiver-------------------------
3225 // If the profile has seen exactly one type, narrow to exactly that type.
3226 // Subsequent type checks will always fold up.
3227 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
3228                                              const TypeKlassPtr* require_klass,
3229                                              ciKlass* spec_klass,
3230                                              bool safe_for_replace) {
3231   if (!UseTypeProfile || !TypeProfileCasts) return nullptr;
3232 
3233   Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != nullptr);
3234 
3235   // Make sure we haven't already deoptimized from this tactic.
3236   if (too_many_traps_or_recompiles(reason))
3237     return nullptr;
3238 
3239   // (No, this isn't a call, but it's enough like a virtual call
3240   // to use the same ciMethod accessor to get the profile info...)
3241   // If we have a speculative type use it instead of profiling (which
3242   // may not help us)
3243   ciKlass* exact_kls = spec_klass == nullptr ? profile_has_unique_klass() : spec_klass;
3244   if (exact_kls != nullptr) {// no cast failures here
3245     if (require_klass == nullptr ||
3246         C->static_subtype_check(require_klass, TypeKlassPtr::make(exact_kls, Type::trust_interfaces)) == Compile::SSC_always_true) {
3247       // If we narrow the type to match what the type profile sees or
3248       // the speculative type, we can then remove the rest of the
3249       // cast.
3250       // This is a win, even if the exact_kls is very specific,
3251       // because downstream operations, such as method calls,
3252       // will often benefit from the sharper type.
3253       Node* exact_obj = not_null_obj; // will get updated in place...
3254       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
3255                                             &exact_obj);
3256       { PreserveJVMState pjvms(this);
3257         set_control(slow_ctl);
3258         uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile);
3259       }
3260       if (safe_for_replace) {
3261         replace_in_map(not_null_obj, exact_obj);
3262       }
3263       return exact_obj;
3264     }
3265     // assert(ssc == Compile::SSC_always_true)... except maybe the profile lied to us.
3266   }
3267 
3268   return nullptr;
3269 }
3270 
3271 /**
3272  * Cast obj to type and emit guard unless we had too many traps here
3273  * already
3274  *
3275  * @param obj       node being casted
3276  * @param type      type to cast the node to
3277  * @param not_null  true if we know node cannot be null
3278  */
3279 Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
3280                                         ciKlass* type,
3281                                         bool not_null) {
3282   if (stopped()) {
3283     return obj;
3284   }
3285 
3286   // type is null if profiling tells us this object is always null
3287   if (type != nullptr) {
3288     Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
3289     Deoptimization::DeoptReason null_reason = Deoptimization::Reason_speculate_null_check;
3290 
3291     if (!too_many_traps_or_recompiles(null_reason) &&
3292         !too_many_traps_or_recompiles(class_reason)) {
3293       Node* not_null_obj = nullptr;
3294       // not_null is true if we know the object is not null and
3295       // there's no need for a null check
3296       if (!not_null) {
3297         Node* null_ctl = top();
3298         not_null_obj = null_check_oop(obj, &null_ctl, true, true, true);
3299         assert(null_ctl->is_top(), "no null control here");
3300       } else {
3301         not_null_obj = obj;
3302       }
3303 
3304       Node* exact_obj = not_null_obj;
3305       ciKlass* exact_kls = type;
3306       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
3307                                             &exact_obj);
3308       {
3309         PreserveJVMState pjvms(this);
3310         set_control(slow_ctl);
3311         uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile);
3312       }
3313       replace_in_map(not_null_obj, exact_obj);
3314       obj = exact_obj;
3315     }
3316   } else {
3317     if (!too_many_traps_or_recompiles(Deoptimization::Reason_null_assert)) {
3318       Node* exact_obj = null_assert(obj);
3319       replace_in_map(obj, exact_obj);
3320       obj = exact_obj;
3321     }
3322   }
3323   return obj;
3324 }
3325 
3326 //-------------------------------gen_instanceof--------------------------------
3327 // Generate an instance-of idiom.  Used by both the instance-of bytecode
3328 // and the reflective instance-of call.
3329 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
3330   kill_dead_locals();           // Benefit all the uncommon traps
3331   assert( !stopped(), "dead parse path should be checked in callers" );
3332   assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
3333          "must check for not-null not-dead klass in callers");
3334 
3335   // Make the merge point
3336   enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
3337   RegionNode* region = new RegionNode(PATH_LIMIT);
3338   Node*       phi    = new PhiNode(region, TypeInt::BOOL);
3339   C->set_has_split_ifs(true); // Has chance for split-if optimization
3340 
3341   ciProfileData* data = nullptr;
3342   if (java_bc() == Bytecodes::_instanceof) {  // Only for the bytecode
3343     data = method()->method_data()->bci_to_data(bci());
3344   }
3345   bool speculative_not_null = false;
3346   bool never_see_null = (ProfileDynamicTypes  // aggressive use of profile
3347                          && seems_never_null(obj, data, speculative_not_null));
3348 
3349   // Null check; get casted pointer; set region slot 3
3350   Node* null_ctl = top();
3351   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3352 
3353   // If not_null_obj is dead, only null-path is taken
3354   if (stopped()) {              // Doing instance-of on a null?
3355     set_control(null_ctl);
3356     return intcon(0);
3357   }
3358   region->init_req(_null_path, null_ctl);
3359   phi   ->init_req(_null_path, intcon(0)); // Set null path value
3360   if (null_ctl == top()) {
3361     // Do this eagerly, so that pattern matches like is_diamond_phi
3362     // will work even during parsing.
3363     assert(_null_path == PATH_LIMIT-1, "delete last");
3364     region->del_req(_null_path);
3365     phi   ->del_req(_null_path);
3366   }
3367 
3368   // Do we know the type check always succeed?
3369   bool known_statically = false;
3370   if (_gvn.type(superklass)->singleton()) {
3371     const TypeKlassPtr* superk = _gvn.type(superklass)->is_klassptr();
3372     const TypeKlassPtr* subk = _gvn.type(obj)->is_oopptr()->as_klass_type();
3373     if (subk->is_loaded()) {
3374       int static_res = C->static_subtype_check(superk, subk);
3375       known_statically = (static_res == Compile::SSC_always_true || static_res == Compile::SSC_always_false);
3376     }
3377   }
3378 
3379   if (!known_statically) {
3380     const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3381     // We may not have profiling here or it may not help us. If we
3382     // have a speculative type use it to perform an exact cast.
3383     ciKlass* spec_obj_type = obj_type->speculative_type();
3384     if (spec_obj_type != nullptr || (ProfileDynamicTypes && data != nullptr)) {
3385       Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, nullptr, spec_obj_type, safe_for_replace);
3386       if (stopped()) {            // Profile disagrees with this path.
3387         set_control(null_ctl);    // Null is the only remaining possibility.
3388         return intcon(0);
3389       }
3390       if (cast_obj != nullptr) {
3391         not_null_obj = cast_obj;
3392       }
3393     }
3394   }
3395 
3396   // Generate the subtype check
3397   Node* not_subtype_ctrl = gen_subtype_check(not_null_obj, superklass);
3398 
3399   // Plug in the success path to the general merge in slot 1.
3400   region->init_req(_obj_path, control());
3401   phi   ->init_req(_obj_path, intcon(1));
3402 
3403   // Plug in the failing path to the general merge in slot 2.
3404   region->init_req(_fail_path, not_subtype_ctrl);
3405   phi   ->init_req(_fail_path, intcon(0));
3406 
3407   // Return final merged results
3408   set_control( _gvn.transform(region) );
3409   record_for_igvn(region);
3410 
3411   // If we know the type check always succeeds then we don't use the
3412   // profiling data at this bytecode. Don't lose it, feed it to the
3413   // type system as a speculative type.
3414   if (safe_for_replace) {
3415     Node* casted_obj = record_profiled_receiver_for_speculation(obj);
3416     replace_in_map(obj, casted_obj);
3417   }
3418 
3419   return _gvn.transform(phi);
3420 }
3421 
3422 //-------------------------------gen_checkcast---------------------------------
3423 // Generate a checkcast idiom.  Used by both the checkcast bytecode and the
3424 // array store bytecode.  Stack must be as-if BEFORE doing the bytecode so the
3425 // uncommon-trap paths work.  Adjust stack after this call.
3426 // If failure_control is supplied and not null, it is filled in with
3427 // the control edge for the cast failure.  Otherwise, an appropriate
3428 // uncommon trap or exception is thrown.
3429 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
3430                               Node* *failure_control) {
3431   kill_dead_locals();           // Benefit all the uncommon traps
3432   const TypeKlassPtr* klass_ptr_type = _gvn.type(superklass)->is_klassptr();
3433   const TypeKlassPtr* improved_klass_ptr_type = klass_ptr_type->try_improve();
3434   const TypeOopPtr* toop = improved_klass_ptr_type->cast_to_exactness(false)->as_instance_type();
3435 
3436   // Fast cutout:  Check the case that the cast is vacuously true.
3437   // This detects the common cases where the test will short-circuit
3438   // away completely.  We do this before we perform the null check,
3439   // because if the test is going to turn into zero code, we don't
3440   // want a residual null check left around.  (Causes a slowdown,
3441   // for example, in some objArray manipulations, such as a[i]=a[j].)
3442   if (improved_klass_ptr_type->singleton()) {
3443     const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
3444     if (objtp != nullptr) {
3445       switch (C->static_subtype_check(improved_klass_ptr_type, objtp->as_klass_type())) {
3446       case Compile::SSC_always_true:
3447         // If we know the type check always succeed then we don't use
3448         // the profiling data at this bytecode. Don't lose it, feed it
3449         // to the type system as a speculative type.
3450         return record_profiled_receiver_for_speculation(obj);
3451       case Compile::SSC_always_false:
3452         // It needs a null check because a null will *pass* the cast check.
3453         // A non-null value will always produce an exception.
3454         if (!objtp->maybe_null()) {
3455           bool is_aastore = (java_bc() == Bytecodes::_aastore);
3456           Deoptimization::DeoptReason reason = is_aastore ?
3457             Deoptimization::Reason_array_check : Deoptimization::Reason_class_check;
3458           builtin_throw(reason);
3459           return top();
3460         } else if (!too_many_traps_or_recompiles(Deoptimization::Reason_null_assert)) {
3461           return null_assert(obj);
3462         }
3463         break; // Fall through to full check
3464       default:
3465         break;
3466       }
3467     }
3468   }
3469 
3470   ciProfileData* data = nullptr;
3471   bool safe_for_replace = false;
3472   if (failure_control == nullptr) {        // use MDO in regular case only
3473     assert(java_bc() == Bytecodes::_aastore ||
3474            java_bc() == Bytecodes::_checkcast,
3475            "interpreter profiles type checks only for these BCs");
3476     data = method()->method_data()->bci_to_data(bci());
3477     safe_for_replace = true;
3478   }
3479 
3480   // Make the merge point
3481   enum { _obj_path = 1, _null_path, PATH_LIMIT };
3482   RegionNode* region = new RegionNode(PATH_LIMIT);
3483   Node*       phi    = new PhiNode(region, toop);
3484   C->set_has_split_ifs(true); // Has chance for split-if optimization
3485 
3486   // Use null-cast information if it is available
3487   bool speculative_not_null = false;
3488   bool never_see_null = ((failure_control == nullptr)  // regular case only
3489                          && seems_never_null(obj, data, speculative_not_null));
3490 
3491   // Null check; get casted pointer; set region slot 3
3492   Node* null_ctl = top();
3493   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3494 
3495   // If not_null_obj is dead, only null-path is taken
3496   if (stopped()) {              // Doing instance-of on a null?
3497     set_control(null_ctl);
3498     return null();
3499   }
3500   region->init_req(_null_path, null_ctl);
3501   phi   ->init_req(_null_path, null());  // Set null path value
3502   if (null_ctl == top()) {
3503     // Do this eagerly, so that pattern matches like is_diamond_phi
3504     // will work even during parsing.
3505     assert(_null_path == PATH_LIMIT-1, "delete last");
3506     region->del_req(_null_path);
3507     phi   ->del_req(_null_path);
3508   }
3509 
3510   Node* cast_obj = nullptr;
3511   if (improved_klass_ptr_type->klass_is_exact()) {
3512     // The following optimization tries to statically cast the speculative type of the object
3513     // (for example obtained during profiling) to the type of the superklass and then do a
3514     // dynamic check that the type of the object is what we expect. To work correctly
3515     // for checkcast and aastore the type of superklass should be exact.
3516     const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3517     // We may not have profiling here or it may not help us. If we have
3518     // a speculative type use it to perform an exact cast.
3519     ciKlass* spec_obj_type = obj_type->speculative_type();
3520     if (spec_obj_type != nullptr || data != nullptr) {
3521       cast_obj = maybe_cast_profiled_receiver(not_null_obj, improved_klass_ptr_type, spec_obj_type, safe_for_replace);
3522       if (cast_obj != nullptr) {
3523         if (failure_control != nullptr) // failure is now impossible
3524           (*failure_control) = top();
3525         // adjust the type of the phi to the exact klass:
3526         phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3527       }
3528     }
3529   }
3530 
3531   if (cast_obj == nullptr) {
3532     // Generate the subtype check
3533     Node* improved_superklass = superklass;
3534     if (improved_klass_ptr_type != klass_ptr_type && improved_klass_ptr_type->singleton()) {
3535       improved_superklass = makecon(improved_klass_ptr_type);
3536     }
3537     Node* not_subtype_ctrl = gen_subtype_check(not_null_obj, improved_superklass);
3538 
3539     // Plug in success path into the merge
3540     cast_obj = _gvn.transform(new CheckCastPPNode(control(), not_null_obj, toop));
3541     // Failure path ends in uncommon trap (or may be dead - failure impossible)
3542     if (failure_control == nullptr) {
3543       if (not_subtype_ctrl != top()) { // If failure is possible
3544         PreserveJVMState pjvms(this);
3545         set_control(not_subtype_ctrl);
3546         bool is_aastore = (java_bc() == Bytecodes::_aastore);
3547         Deoptimization::DeoptReason reason = is_aastore ?
3548           Deoptimization::Reason_array_check : Deoptimization::Reason_class_check;
3549         builtin_throw(reason);
3550       }
3551     } else {
3552       (*failure_control) = not_subtype_ctrl;
3553     }
3554   }
3555 
3556   region->init_req(_obj_path, control());
3557   phi   ->init_req(_obj_path, cast_obj);
3558 
3559   // A merge of null or Casted-NotNull obj
3560   Node* res = _gvn.transform(phi);
3561 
3562   // Note I do NOT always 'replace_in_map(obj,result)' here.
3563   //  if( tk->klass()->can_be_primary_super()  )
3564     // This means that if I successfully store an Object into an array-of-String
3565     // I 'forget' that the Object is really now known to be a String.  I have to
3566     // do this because we don't have true union types for interfaces - if I store
3567     // a Baz into an array-of-Interface and then tell the optimizer it's an
3568     // Interface, I forget that it's also a Baz and cannot do Baz-like field
3569     // references to it.  FIX THIS WHEN UNION TYPES APPEAR!
3570   //  replace_in_map( obj, res );
3571 
3572   // Return final merged results
3573   set_control( _gvn.transform(region) );
3574   record_for_igvn(region);
3575 
3576   return record_profiled_receiver_for_speculation(res);
3577 }
3578 
3579 //------------------------------next_monitor-----------------------------------
3580 // What number should be given to the next monitor?
3581 int GraphKit::next_monitor() {
3582   int current = jvms()->monitor_depth()* C->sync_stack_slots();
3583   int next = current + C->sync_stack_slots();
3584   // Keep the toplevel high water mark current:
3585   if (C->fixed_slots() < next)  C->set_fixed_slots(next);
3586   return current;
3587 }
3588 
3589 //------------------------------insert_mem_bar---------------------------------
3590 // Memory barrier to avoid floating things around
3591 // The membar serves as a pinch point between both control and all memory slices.
3592 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3593   MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3594   mb->init_req(TypeFunc::Control, control());
3595   mb->init_req(TypeFunc::Memory,  reset_memory());
3596   Node* membar = _gvn.transform(mb);
3597   record_for_igvn(membar);
3598   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3599   set_all_memory_call(membar);
3600   return membar;
3601 }
3602 
3603 //-------------------------insert_mem_bar_volatile----------------------------
3604 // Memory barrier to avoid floating things around
3605 // The membar serves as a pinch point between both control and memory(alias_idx).
3606 // If you want to make a pinch point on all memory slices, do not use this
3607 // function (even with AliasIdxBot); use insert_mem_bar() instead.
3608 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3609   // When Parse::do_put_xxx updates a volatile field, it appends a series
3610   // of MemBarVolatile nodes, one for *each* volatile field alias category.
3611   // The first membar is on the same memory slice as the field store opcode.
3612   // This forces the membar to follow the store.  (Bug 6500685 broke this.)
3613   // All the other membars (for other volatile slices, including AliasIdxBot,
3614   // which stands for all unknown volatile slices) are control-dependent
3615   // on the first membar.  This prevents later volatile loads or stores
3616   // from sliding up past the just-emitted store.
3617 
3618   MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3619   mb->set_req(TypeFunc::Control,control());
3620   if (alias_idx == Compile::AliasIdxBot) {
3621     mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3622   } else {
3623     assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3624     mb->set_req(TypeFunc::Memory, memory(alias_idx));
3625   }
3626   Node* membar = _gvn.transform(mb);
3627   record_for_igvn(membar);
3628   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3629   if (alias_idx == Compile::AliasIdxBot) {
3630     merged_memory()->set_base_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)));
3631   } else {
3632     set_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)),alias_idx);
3633   }
3634   return membar;
3635 }
3636 
3637 //------------------------------shared_lock------------------------------------
3638 // Emit locking code.
3639 FastLockNode* GraphKit::shared_lock(Node* obj) {
3640   // bci is either a monitorenter bc or InvocationEntryBci
3641   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3642   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3643 
3644   if (stopped())                // Dead monitor?
3645     return nullptr;
3646 
3647   assert(dead_locals_are_killed(), "should kill locals before sync. point");
3648 
3649   // Box the stack location
3650   Node* box = new BoxLockNode(next_monitor());
3651   // Check for bailout after new BoxLockNode
3652   if (failing()) { return nullptr; }
3653   box = _gvn.transform(box);
3654   Node* mem = reset_memory();
3655 
3656   FastLockNode * flock = _gvn.transform(new FastLockNode(nullptr, obj, box) )->as_FastLock();
3657 
3658   // Add monitor to debug info for the slow path.  If we block inside the
3659   // slow path and de-opt, we need the monitor hanging around
3660   map()->push_monitor( flock );
3661 
3662   const TypeFunc *tf = LockNode::lock_type();
3663   LockNode *lock = new LockNode(C, tf);
3664 
3665   lock->init_req( TypeFunc::Control, control() );
3666   lock->init_req( TypeFunc::Memory , mem );
3667   lock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
3668   lock->init_req( TypeFunc::FramePtr, frameptr() );
3669   lock->init_req( TypeFunc::ReturnAdr, top() );
3670 
3671   lock->init_req(TypeFunc::Parms + 0, obj);
3672   lock->init_req(TypeFunc::Parms + 1, box);
3673   lock->init_req(TypeFunc::Parms + 2, flock);
3674   add_safepoint_edges(lock);
3675 
3676   lock = _gvn.transform( lock )->as_Lock();
3677 
3678   // lock has no side-effects, sets few values
3679   set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3680 
3681   insert_mem_bar(Op_MemBarAcquireLock);
3682 
3683   // Add this to the worklist so that the lock can be eliminated
3684   record_for_igvn(lock);
3685 
3686 #ifndef PRODUCT
3687   if (PrintLockStatistics) {
3688     // Update the counter for this lock.  Don't bother using an atomic
3689     // operation since we don't require absolute accuracy.
3690     lock->create_lock_counter(map()->jvms());
3691     increment_counter(lock->counter()->addr());
3692   }
3693 #endif
3694 
3695   return flock;
3696 }
3697 
3698 
3699 //------------------------------shared_unlock----------------------------------
3700 // Emit unlocking code.
3701 void GraphKit::shared_unlock(Node* box, Node* obj) {
3702   // bci is either a monitorenter bc or InvocationEntryBci
3703   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3704   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3705 
3706   if (stopped()) {               // Dead monitor?
3707     map()->pop_monitor();        // Kill monitor from debug info
3708     return;
3709   }
3710 
3711   // Memory barrier to avoid floating things down past the locked region
3712   insert_mem_bar(Op_MemBarReleaseLock);
3713 
3714   const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3715   UnlockNode *unlock = new UnlockNode(C, tf);
3716 #ifdef ASSERT
3717   unlock->set_dbg_jvms(sync_jvms());
3718 #endif
3719   uint raw_idx = Compile::AliasIdxRaw;
3720   unlock->init_req( TypeFunc::Control, control() );
3721   unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3722   unlock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
3723   unlock->init_req( TypeFunc::FramePtr, frameptr() );
3724   unlock->init_req( TypeFunc::ReturnAdr, top() );
3725 
3726   unlock->init_req(TypeFunc::Parms + 0, obj);
3727   unlock->init_req(TypeFunc::Parms + 1, box);
3728   unlock = _gvn.transform(unlock)->as_Unlock();
3729 
3730   Node* mem = reset_memory();
3731 
3732   // unlock has no side-effects, sets few values
3733   set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3734 
3735   // Kill monitor from debug info
3736   map()->pop_monitor( );
3737 }
3738 
3739 //-------------------------------get_layout_helper-----------------------------
3740 // If the given klass is a constant or known to be an array,
3741 // fetch the constant layout helper value into constant_value
3742 // and return null.  Otherwise, load the non-constant
3743 // layout helper value, and return the node which represents it.
3744 // This two-faced routine is useful because allocation sites
3745 // almost always feature constant types.
3746 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3747   const TypeKlassPtr* klass_t = _gvn.type(klass_node)->isa_klassptr();
3748   if (!StressReflectiveCode && klass_t != nullptr) {
3749     bool xklass = klass_t->klass_is_exact();
3750     if (xklass || (klass_t->isa_aryklassptr() && klass_t->is_aryklassptr()->elem() != Type::BOTTOM)) {
3751       jint lhelper;
3752       if (klass_t->isa_aryklassptr()) {
3753         BasicType elem = klass_t->as_instance_type()->isa_aryptr()->elem()->array_element_basic_type();
3754         if (is_reference_type(elem, true)) {
3755           elem = T_OBJECT;
3756         }
3757         lhelper = Klass::array_layout_helper(elem);
3758       } else {
3759         lhelper = klass_t->is_instklassptr()->exact_klass()->layout_helper();
3760       }
3761       if (lhelper != Klass::_lh_neutral_value) {
3762         constant_value = lhelper;
3763         return (Node*) nullptr;
3764       }
3765     }
3766   }
3767   constant_value = Klass::_lh_neutral_value;  // put in a known value
3768   Node* lhp = basic_plus_adr(top(), klass_node, in_bytes(Klass::layout_helper_offset()));
3769   return make_load(nullptr, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3770 }
3771 
3772 // We just put in an allocate/initialize with a big raw-memory effect.
3773 // Hook selected additional alias categories on the initialization.
3774 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3775                                 MergeMemNode* init_in_merge,
3776                                 Node* init_out_raw) {
3777   DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3778   assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3779 
3780   Node* prevmem = kit.memory(alias_idx);
3781   init_in_merge->set_memory_at(alias_idx, prevmem);
3782   kit.set_memory(init_out_raw, alias_idx);
3783 }
3784 
3785 //---------------------------set_output_for_allocation-------------------------
3786 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3787                                           const TypeOopPtr* oop_type,
3788                                           bool deoptimize_on_exception) {
3789   int rawidx = Compile::AliasIdxRaw;
3790   alloc->set_req( TypeFunc::FramePtr, frameptr() );
3791   add_safepoint_edges(alloc);
3792   Node* allocx = _gvn.transform(alloc);
3793   set_control( _gvn.transform(new ProjNode(allocx, TypeFunc::Control) ) );
3794   // create memory projection for i_o
3795   set_memory ( _gvn.transform( new ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3796   make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception);
3797 
3798   // create a memory projection as for the normal control path
3799   Node* malloc = _gvn.transform(new ProjNode(allocx, TypeFunc::Memory));
3800   set_memory(malloc, rawidx);
3801 
3802   // a normal slow-call doesn't change i_o, but an allocation does
3803   // we create a separate i_o projection for the normal control path
3804   set_i_o(_gvn.transform( new ProjNode(allocx, TypeFunc::I_O, false) ) );
3805   Node* rawoop = _gvn.transform( new ProjNode(allocx, TypeFunc::Parms) );
3806 
3807   // put in an initialization barrier
3808   InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3809                                                  rawoop)->as_Initialize();
3810   assert(alloc->initialization() == init,  "2-way macro link must work");
3811   assert(init ->allocation()     == alloc, "2-way macro link must work");
3812   {
3813     // Extract memory strands which may participate in the new object's
3814     // initialization, and source them from the new InitializeNode.
3815     // This will allow us to observe initializations when they occur,
3816     // and link them properly (as a group) to the InitializeNode.
3817     assert(init->in(InitializeNode::Memory) == malloc, "");
3818     MergeMemNode* minit_in = MergeMemNode::make(malloc);
3819     init->set_req(InitializeNode::Memory, minit_in);
3820     record_for_igvn(minit_in); // fold it up later, if possible
3821     Node* minit_out = memory(rawidx);
3822     assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3823     int mark_idx = C->get_alias_index(oop_type->add_offset(oopDesc::mark_offset_in_bytes()));
3824     // Add an edge in the MergeMem for the header fields so an access to one of those has correct memory state.
3825     // Use one NarrowMemProjNode per slice to properly record the adr type of each slice. The Initialize node will have
3826     // multiple projections as a result.
3827     set_memory(_gvn.transform(new NarrowMemProjNode(init, C->get_adr_type(mark_idx))), mark_idx);
3828     int klass_idx = C->get_alias_index(oop_type->add_offset(oopDesc::klass_offset_in_bytes()));
3829     set_memory(_gvn.transform(new NarrowMemProjNode(init, C->get_adr_type(klass_idx))), klass_idx);
3830     if (oop_type->isa_aryptr()) {
3831       const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3832       int            elemidx  = C->get_alias_index(telemref);
3833       hook_memory_on_init(*this, elemidx, minit_in, _gvn.transform(new NarrowMemProjNode(init, C->get_adr_type(elemidx))));
3834     } else if (oop_type->isa_instptr()) {
3835       ciInstanceKlass* ik = oop_type->is_instptr()->instance_klass();
3836       for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3837         ciField* field = ik->nonstatic_field_at(i);
3838         if (field->offset_in_bytes() >= TrackedInitializationLimit * HeapWordSize)
3839           continue;  // do not bother to track really large numbers of fields
3840         // Find (or create) the alias category for this field:
3841         int fieldidx = C->alias_type(field)->index();
3842         hook_memory_on_init(*this, fieldidx, minit_in, _gvn.transform(new NarrowMemProjNode(init, C->get_adr_type(fieldidx))));
3843       }
3844     }
3845   }
3846 
3847   // Cast raw oop to the real thing...
3848   Node* javaoop = new CheckCastPPNode(control(), rawoop, oop_type);
3849   javaoop = _gvn.transform(javaoop);
3850   C->set_recent_alloc(control(), javaoop);
3851   assert(just_allocated_object(control()) == javaoop, "just allocated");
3852 
3853 #ifdef ASSERT
3854   { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3855     assert(AllocateNode::Ideal_allocation(rawoop) == alloc,
3856            "Ideal_allocation works");
3857     assert(AllocateNode::Ideal_allocation(javaoop) == alloc,
3858            "Ideal_allocation works");
3859     if (alloc->is_AllocateArray()) {
3860       assert(AllocateArrayNode::Ideal_array_allocation(rawoop) == alloc->as_AllocateArray(),
3861              "Ideal_allocation works");
3862       assert(AllocateArrayNode::Ideal_array_allocation(javaoop) == alloc->as_AllocateArray(),
3863              "Ideal_allocation works");
3864     } else {
3865       assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3866     }
3867   }
3868 #endif //ASSERT
3869 
3870   return javaoop;
3871 }
3872 
3873 //---------------------------new_instance--------------------------------------
3874 // This routine takes a klass_node which may be constant (for a static type)
3875 // or may be non-constant (for reflective code).  It will work equally well
3876 // for either, and the graph will fold nicely if the optimizer later reduces
3877 // the type to a constant.
3878 // The optional arguments are for specialized use by intrinsics:
3879 //  - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3880 //  - If 'return_size_val', report the total object size to the caller.
3881 //  - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3882 Node* GraphKit::new_instance(Node* klass_node,
3883                              Node* extra_slow_test,
3884                              Node* *return_size_val,
3885                              bool deoptimize_on_exception) {
3886   // Compute size in doublewords
3887   // The size is always an integral number of doublewords, represented
3888   // as a positive bytewise size stored in the klass's layout_helper.
3889   // The layout_helper also encodes (in a low bit) the need for a slow path.
3890   jint  layout_con = Klass::_lh_neutral_value;
3891   Node* layout_val = get_layout_helper(klass_node, layout_con);
3892   int   layout_is_con = (layout_val == nullptr);
3893 
3894   if (extra_slow_test == nullptr)  extra_slow_test = intcon(0);
3895   // Generate the initial go-slow test.  It's either ALWAYS (return a
3896   // Node for 1) or NEVER (return a null) or perhaps (in the reflective
3897   // case) a computed value derived from the layout_helper.
3898   Node* initial_slow_test = nullptr;
3899   if (layout_is_con) {
3900     assert(!StressReflectiveCode, "stress mode does not use these paths");
3901     bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3902     initial_slow_test = must_go_slow ? intcon(1) : extra_slow_test;
3903   } else {   // reflective case
3904     // This reflective path is used by Unsafe.allocateInstance.
3905     // (It may be stress-tested by specifying StressReflectiveCode.)
3906     // Basically, we want to get into the VM is there's an illegal argument.
3907     Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3908     initial_slow_test = _gvn.transform( new AndINode(layout_val, bit) );
3909     if (extra_slow_test != intcon(0)) {
3910       initial_slow_test = _gvn.transform( new OrINode(initial_slow_test, extra_slow_test) );
3911     }
3912     // (Macro-expander will further convert this to a Bool, if necessary.)
3913   }
3914 
3915   // Find the size in bytes.  This is easy; it's the layout_helper.
3916   // The size value must be valid even if the slow path is taken.
3917   Node* size = nullptr;
3918   if (layout_is_con) {
3919     size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3920   } else {   // reflective case
3921     // This reflective path is used by clone and Unsafe.allocateInstance.
3922     size = ConvI2X(layout_val);
3923 
3924     // Clear the low bits to extract layout_helper_size_in_bytes:
3925     assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3926     Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3927     size = _gvn.transform( new AndXNode(size, mask) );
3928   }
3929   if (return_size_val != nullptr) {
3930     (*return_size_val) = size;
3931   }
3932 
3933   // This is a precise notnull oop of the klass.
3934   // (Actually, it need not be precise if this is a reflective allocation.)
3935   // It's what we cast the result to.
3936   const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3937   if (!tklass)  tklass = TypeInstKlassPtr::OBJECT;
3938   const TypeOopPtr* oop_type = tklass->as_instance_type();
3939 
3940   // Now generate allocation code
3941 
3942   // The entire memory state is needed for slow path of the allocation
3943   // since GC and deoptimization can happened.
3944   Node *mem = reset_memory();
3945   set_all_memory(mem); // Create new memory state
3946 
3947   AllocateNode* alloc = new AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3948                                          control(), mem, i_o(),
3949                                          size, klass_node,
3950                                          initial_slow_test);
3951 
3952   return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception);
3953 }
3954 
3955 //-------------------------------new_array-------------------------------------
3956 // helper for both newarray and anewarray
3957 // The 'length' parameter is (obviously) the length of the array.
3958 // The optional arguments are for specialized use by intrinsics:
3959 //  - If 'return_size_val', report the non-padded array size (sum of header size
3960 //    and array body) to the caller.
3961 //  - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3962 Node* GraphKit::new_array(Node* klass_node,     // array klass (maybe variable)
3963                           Node* length,         // number of array elements
3964                           int   nargs,          // number of arguments to push back for uncommon trap
3965                           Node* *return_size_val,
3966                           bool deoptimize_on_exception) {
3967   jint  layout_con = Klass::_lh_neutral_value;
3968   Node* layout_val = get_layout_helper(klass_node, layout_con);
3969   int   layout_is_con = (layout_val == nullptr);
3970 
3971   if (!layout_is_con && !StressReflectiveCode &&
3972       !too_many_traps(Deoptimization::Reason_class_check)) {
3973     // This is a reflective array creation site.
3974     // Optimistically assume that it is a subtype of Object[],
3975     // so that we can fold up all the address arithmetic.
3976     layout_con = Klass::array_layout_helper(T_OBJECT);
3977     Node* cmp_lh = _gvn.transform( new CmpINode(layout_val, intcon(layout_con)) );
3978     Node* bol_lh = _gvn.transform( new BoolNode(cmp_lh, BoolTest::eq) );
3979     { BuildCutout unless(this, bol_lh, PROB_MAX);
3980       inc_sp(nargs);
3981       uncommon_trap(Deoptimization::Reason_class_check,
3982                     Deoptimization::Action_maybe_recompile);
3983     }
3984     layout_val = nullptr;
3985     layout_is_con = true;
3986   }
3987 
3988   // Generate the initial go-slow test.  Make sure we do not overflow
3989   // if length is huge (near 2Gig) or negative!  We do not need
3990   // exact double-words here, just a close approximation of needed
3991   // double-words.  We can't add any offset or rounding bits, lest we
3992   // take a size -1 of bytes and make it positive.  Use an unsigned
3993   // compare, so negative sizes look hugely positive.
3994   int fast_size_limit = FastAllocateSizeLimit;
3995   if (layout_is_con) {
3996     assert(!StressReflectiveCode, "stress mode does not use these paths");
3997     // Increase the size limit if we have exact knowledge of array type.
3998     int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3999     assert(fast_size_limit == 0 || count_leading_zeros(fast_size_limit) > static_cast<unsigned>(LogBytesPerLong - log2_esize),
4000            "fast_size_limit (%d) overflow when shifted left by %d", fast_size_limit, LogBytesPerLong - log2_esize);
4001     fast_size_limit <<= (LogBytesPerLong - log2_esize);
4002   }
4003 
4004   Node* initial_slow_cmp  = _gvn.transform( new CmpUNode( length, intcon( fast_size_limit ) ) );
4005   Node* initial_slow_test = _gvn.transform( new BoolNode( initial_slow_cmp, BoolTest::gt ) );
4006 
4007   // --- Size Computation ---
4008   // array_size = round_to_heap(array_header + (length << elem_shift));
4009   // where round_to_heap(x) == align_to(x, MinObjAlignmentInBytes)
4010   // and align_to(x, y) == ((x + y-1) & ~(y-1))
4011   // The rounding mask is strength-reduced, if possible.
4012   int round_mask = MinObjAlignmentInBytes - 1;
4013   Node* header_size = nullptr;
4014   // (T_BYTE has the weakest alignment and size restrictions...)
4015   if (layout_is_con) {
4016     int       hsize  = Klass::layout_helper_header_size(layout_con);
4017     int       eshift = Klass::layout_helper_log2_element_size(layout_con);
4018     if ((round_mask & ~right_n_bits(eshift)) == 0)
4019       round_mask = 0;  // strength-reduce it if it goes away completely
4020     assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
4021     int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
4022     assert(header_size_min <= hsize, "generic minimum is smallest");
4023     header_size = intcon(hsize);
4024   } else {
4025     Node* hss   = intcon(Klass::_lh_header_size_shift);
4026     Node* hsm   = intcon(Klass::_lh_header_size_mask);
4027     header_size = _gvn.transform(new URShiftINode(layout_val, hss));
4028     header_size = _gvn.transform(new AndINode(header_size, hsm));
4029   }
4030 
4031   Node* elem_shift = nullptr;
4032   if (layout_is_con) {
4033     int eshift = Klass::layout_helper_log2_element_size(layout_con);
4034     if (eshift != 0)
4035       elem_shift = intcon(eshift);
4036   } else {
4037     // There is no need to mask or shift this value.
4038     // The semantics of LShiftINode include an implicit mask to 0x1F.
4039     assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
4040     elem_shift = layout_val;
4041   }
4042 
4043   // Transition to native address size for all offset calculations:
4044   Node* lengthx = ConvI2X(length);
4045   Node* headerx = ConvI2X(header_size);
4046 #ifdef _LP64
4047   { const TypeInt* tilen = _gvn.find_int_type(length);
4048     if (tilen != nullptr && tilen->_lo < 0) {
4049       // Add a manual constraint to a positive range.  Cf. array_element_address.
4050       jint size_max = fast_size_limit;
4051       if (size_max > tilen->_hi && tilen->_hi >= 0) {
4052         size_max = tilen->_hi;
4053       }
4054       const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin);
4055 
4056       // Only do a narrow I2L conversion if the range check passed.
4057       IfNode* iff = new IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
4058       _gvn.transform(iff);
4059       RegionNode* region = new RegionNode(3);
4060       _gvn.set_type(region, Type::CONTROL);
4061       lengthx = new PhiNode(region, TypeLong::LONG);
4062       _gvn.set_type(lengthx, TypeLong::LONG);
4063 
4064       // Range check passed. Use ConvI2L node with narrow type.
4065       Node* passed = IfFalse(iff);
4066       region->init_req(1, passed);
4067       // Make I2L conversion control dependent to prevent it from
4068       // floating above the range check during loop optimizations.
4069       lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed));
4070 
4071       // Range check failed. Use ConvI2L with wide type because length may be invalid.
4072       region->init_req(2, IfTrue(iff));
4073       lengthx->init_req(2, ConvI2X(length));
4074 
4075       set_control(region);
4076       record_for_igvn(region);
4077       record_for_igvn(lengthx);
4078     }
4079   }
4080 #endif
4081 
4082   // Combine header size and body size for the array copy part, then align (if
4083   // necessary) for the allocation part. This computation cannot overflow,
4084   // because it is used only in two places, one where the length is sharply
4085   // limited, and the other after a successful allocation.
4086   Node* abody = lengthx;
4087   if (elem_shift != nullptr) {
4088     abody = _gvn.transform(new LShiftXNode(lengthx, elem_shift));
4089   }
4090   Node* non_rounded_size = _gvn.transform(new AddXNode(headerx, abody));
4091 
4092   if (return_size_val != nullptr) {
4093     // This is the size
4094     (*return_size_val) = non_rounded_size;
4095   }
4096 
4097   Node* size = non_rounded_size;
4098   if (round_mask != 0) {
4099     Node* mask1 = MakeConX(round_mask);
4100     size = _gvn.transform(new AddXNode(size, mask1));
4101     Node* mask2 = MakeConX(~round_mask);
4102     size = _gvn.transform(new AndXNode(size, mask2));
4103   }
4104   // else if round_mask == 0, the size computation is self-rounding
4105 
4106   // Now generate allocation code
4107 
4108   // The entire memory state is needed for slow path of the allocation
4109   // since GC and deoptimization can happened.
4110   Node *mem = reset_memory();
4111   set_all_memory(mem); // Create new memory state
4112 
4113   if (initial_slow_test->is_Bool()) {
4114     // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
4115     initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
4116   }
4117 
4118   const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
4119   Node* valid_length_test = _gvn.intcon(1);
4120   if (ary_type->isa_aryptr()) {
4121     BasicType bt = ary_type->isa_aryptr()->elem()->array_element_basic_type();
4122     jint max = TypeAryPtr::max_array_length(bt);
4123     Node* valid_length_cmp  = _gvn.transform(new CmpUNode(length, intcon(max)));
4124     valid_length_test = _gvn.transform(new BoolNode(valid_length_cmp, BoolTest::le));
4125   }
4126 
4127   // Create the AllocateArrayNode and its result projections
4128   AllocateArrayNode* alloc
4129     = new AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
4130                             control(), mem, i_o(),
4131                             size, klass_node,
4132                             initial_slow_test,
4133                             length, valid_length_test);
4134 
4135   // Cast to correct type.  Note that the klass_node may be constant or not,
4136   // and in the latter case the actual array type will be inexact also.
4137   // (This happens via a non-constant argument to inline_native_newArray.)
4138   // In any case, the value of klass_node provides the desired array type.
4139   const TypeInt* length_type = _gvn.find_int_type(length);
4140   if (ary_type->isa_aryptr() && length_type != nullptr) {
4141     // Try to get a better type than POS for the size
4142     ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
4143   }
4144 
4145   Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception);
4146 
4147   array_ideal_length(alloc, ary_type, true);
4148   return javaoop;
4149 }
4150 
4151 // The following "Ideal_foo" functions are placed here because they recognize
4152 // the graph shapes created by the functions immediately above.
4153 
4154 //---------------------------Ideal_allocation----------------------------------
4155 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
4156 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr) {
4157   if (ptr == nullptr) {     // reduce dumb test in callers
4158     return nullptr;
4159   }
4160 
4161   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
4162   ptr = bs->step_over_gc_barrier(ptr);
4163 
4164   if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
4165     ptr = ptr->in(1);
4166     if (ptr == nullptr) return nullptr;
4167   }
4168   // Return null for allocations with several casts:
4169   //   j.l.reflect.Array.newInstance(jobject, jint)
4170   //   Object.clone()
4171   // to keep more precise type from last cast.
4172   if (ptr->is_Proj()) {
4173     Node* allo = ptr->in(0);
4174     if (allo != nullptr && allo->is_Allocate()) {
4175       return allo->as_Allocate();
4176     }
4177   }
4178   // Report failure to match.
4179   return nullptr;
4180 }
4181 
4182 // Fancy version which also strips off an offset (and reports it to caller).
4183 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseValues* phase,
4184                                              intptr_t& offset) {
4185   Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
4186   if (base == nullptr)  return nullptr;
4187   return Ideal_allocation(base);
4188 }
4189 
4190 // Trace Initialize <- Proj[Parm] <- Allocate
4191 AllocateNode* InitializeNode::allocation() {
4192   Node* rawoop = in(InitializeNode::RawAddress);
4193   if (rawoop->is_Proj()) {
4194     Node* alloc = rawoop->in(0);
4195     if (alloc->is_Allocate()) {
4196       return alloc->as_Allocate();
4197     }
4198   }
4199   return nullptr;
4200 }
4201 
4202 // Trace Allocate -> Proj[Parm] -> Initialize
4203 InitializeNode* AllocateNode::initialization() {
4204   ProjNode* rawoop = proj_out_or_null(AllocateNode::RawAddress);
4205   if (rawoop == nullptr)  return nullptr;
4206   for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
4207     Node* init = rawoop->fast_out(i);
4208     if (init->is_Initialize()) {
4209       assert(init->as_Initialize()->allocation() == this, "2-way link");
4210       return init->as_Initialize();
4211     }
4212   }
4213   return nullptr;
4214 }
4215 
4216 // Add a Parse Predicate with an uncommon trap on the failing/false path. Normal control will continue on the true path.
4217 void GraphKit::add_parse_predicate(Deoptimization::DeoptReason reason, const int nargs) {
4218   // Too many traps seen?
4219   if (too_many_traps(reason)) {
4220 #ifdef ASSERT
4221     if (TraceLoopPredicate) {
4222       int tc = C->trap_count(reason);
4223       tty->print("too many traps=%s tcount=%d in ",
4224                     Deoptimization::trap_reason_name(reason), tc);
4225       method()->print(); // which method has too many predicate traps
4226       tty->cr();
4227     }
4228 #endif
4229     // We cannot afford to take more traps here,
4230     // do not generate Parse Predicate.
4231     return;
4232   }
4233 
4234   ParsePredicateNode* parse_predicate = new ParsePredicateNode(control(), reason, &_gvn);
4235   _gvn.set_type(parse_predicate, parse_predicate->Value(&_gvn));
4236   Node* if_false = _gvn.transform(new IfFalseNode(parse_predicate));
4237   {
4238     PreserveJVMState pjvms(this);
4239     set_control(if_false);
4240     inc_sp(nargs);
4241     uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
4242   }
4243   Node* if_true = _gvn.transform(new IfTrueNode(parse_predicate));
4244   set_control(if_true);
4245 }
4246 
4247 // Add Parse Predicates which serve as placeholders to create new Runtime Predicates above them. All
4248 // Runtime Predicates inside a Runtime Predicate block share the same uncommon trap as the Parse Predicate.
4249 void GraphKit::add_parse_predicates(int nargs) {
4250   if (ShortRunningLongLoop) {
4251     // Will narrow the limit down with a cast node. Predicates added later may depend on the cast so should be last when
4252     // walking up from the loop.
4253     add_parse_predicate(Deoptimization::Reason_short_running_long_loop, nargs);
4254   }
4255   if (UseLoopPredicate) {
4256     add_parse_predicate(Deoptimization::Reason_predicate, nargs);
4257     if (UseProfiledLoopPredicate) {
4258       add_parse_predicate(Deoptimization::Reason_profile_predicate, nargs);
4259     }
4260   }
4261   if (UseAutoVectorizationPredicate) {
4262     add_parse_predicate(Deoptimization::Reason_auto_vectorization_check, nargs);
4263   }
4264   // Loop Limit Check Predicate should be near the loop.
4265   add_parse_predicate(Deoptimization::Reason_loop_limit_check, nargs);
4266 }
4267 
4268 void GraphKit::sync_kit(IdealKit& ideal) {
4269   set_all_memory(ideal.merged_memory());
4270   set_i_o(ideal.i_o());
4271   set_control(ideal.ctrl());
4272 }
4273 
4274 void GraphKit::final_sync(IdealKit& ideal) {
4275   // Final sync IdealKit and graphKit.
4276   sync_kit(ideal);
4277 }
4278 
4279 Node* GraphKit::load_String_length(Node* str, bool set_ctrl) {
4280   Node* len = load_array_length(load_String_value(str, set_ctrl));
4281   Node* coder = load_String_coder(str, set_ctrl);
4282   // Divide length by 2 if coder is UTF16
4283   return _gvn.transform(new RShiftINode(len, coder));
4284 }
4285 
4286 Node* GraphKit::load_String_value(Node* str, bool set_ctrl) {
4287   int value_offset = java_lang_String::value_offset();
4288   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4289                                                      false, nullptr, 0);
4290   const TypePtr* value_field_type = string_type->add_offset(value_offset);
4291   const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
4292                                                   TypeAry::make(TypeInt::BYTE, TypeInt::POS),
4293                                                   ciTypeArrayKlass::make(T_BYTE), true, 0);
4294   Node* p = basic_plus_adr(str, str, value_offset);
4295   Node* load = access_load_at(str, p, value_field_type, value_type, T_OBJECT,
4296                               IN_HEAP | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0) | MO_UNORDERED);
4297   return load;
4298 }
4299 
4300 Node* GraphKit::load_String_coder(Node* str, bool set_ctrl) {
4301   if (!CompactStrings) {
4302     return intcon(java_lang_String::CODER_UTF16);
4303   }
4304   int coder_offset = java_lang_String::coder_offset();
4305   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4306                                                      false, nullptr, 0);
4307   const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4308 
4309   Node* p = basic_plus_adr(str, str, coder_offset);
4310   Node* load = access_load_at(str, p, coder_field_type, TypeInt::BYTE, T_BYTE,
4311                               IN_HEAP | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0) | MO_UNORDERED);
4312   return load;
4313 }
4314 
4315 void GraphKit::store_String_value(Node* str, Node* value) {
4316   int value_offset = java_lang_String::value_offset();
4317   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4318                                                      false, nullptr, 0);
4319   const TypePtr* value_field_type = string_type->add_offset(value_offset);
4320 
4321   access_store_at(str,  basic_plus_adr(str, value_offset), value_field_type,
4322                   value, TypeAryPtr::BYTES, T_OBJECT, IN_HEAP | MO_UNORDERED);
4323 }
4324 
4325 void GraphKit::store_String_coder(Node* str, Node* value) {
4326   int coder_offset = java_lang_String::coder_offset();
4327   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4328                                                      false, nullptr, 0);
4329   const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4330 
4331   access_store_at(str, basic_plus_adr(str, coder_offset), coder_field_type,
4332                   value, TypeInt::BYTE, T_BYTE, IN_HEAP | MO_UNORDERED);
4333 }
4334 
4335 // Capture src and dst memory state with a MergeMemNode
4336 Node* GraphKit::capture_memory(const TypePtr* src_type, const TypePtr* dst_type) {
4337   if (src_type == dst_type) {
4338     // Types are equal, we don't need a MergeMemNode
4339     return memory(src_type);
4340   }
4341   MergeMemNode* merge = MergeMemNode::make(map()->memory());
4342   record_for_igvn(merge); // fold it up later, if possible
4343   int src_idx = C->get_alias_index(src_type);
4344   int dst_idx = C->get_alias_index(dst_type);
4345   merge->set_memory_at(src_idx, memory(src_idx));
4346   merge->set_memory_at(dst_idx, memory(dst_idx));
4347   return merge;
4348 }
4349 
4350 Node* GraphKit::compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count) {
4351   assert(Matcher::match_rule_supported(Op_StrCompressedCopy), "Intrinsic not supported");
4352   assert(src_type == TypeAryPtr::BYTES || src_type == TypeAryPtr::CHARS, "invalid source type");
4353   // If input and output memory types differ, capture both states to preserve
4354   // the dependency between preceding and subsequent loads/stores.
4355   // For example, the following program:
4356   //  StoreB
4357   //  compress_string
4358   //  LoadB
4359   // has this memory graph (use->def):
4360   //  LoadB -> compress_string -> CharMem
4361   //             ... -> StoreB -> ByteMem
4362   // The intrinsic hides the dependency between LoadB and StoreB, causing
4363   // the load to read from memory not containing the result of the StoreB.
4364   // The correct memory graph should look like this:
4365   //  LoadB -> compress_string -> MergeMem(CharMem, StoreB(ByteMem))
4366   Node* mem = capture_memory(src_type, TypeAryPtr::BYTES);
4367   StrCompressedCopyNode* str = new StrCompressedCopyNode(control(), mem, src, dst, count);
4368   Node* res_mem = _gvn.transform(new SCMemProjNode(_gvn.transform(str)));
4369   set_memory(res_mem, TypeAryPtr::BYTES);
4370   return str;
4371 }
4372 
4373 void GraphKit::inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count) {
4374   assert(Matcher::match_rule_supported(Op_StrInflatedCopy), "Intrinsic not supported");
4375   assert(dst_type == TypeAryPtr::BYTES || dst_type == TypeAryPtr::CHARS, "invalid dest type");
4376   // Capture src and dst memory (see comment in 'compress_string').
4377   Node* mem = capture_memory(TypeAryPtr::BYTES, dst_type);
4378   StrInflatedCopyNode* str = new StrInflatedCopyNode(control(), mem, src, dst, count);
4379   set_memory(_gvn.transform(str), dst_type);
4380 }
4381 
4382 void GraphKit::inflate_string_slow(Node* src, Node* dst, Node* start, Node* count) {
4383   /**
4384    * int i_char = start;
4385    * for (int i_byte = 0; i_byte < count; i_byte++) {
4386    *   dst[i_char++] = (char)(src[i_byte] & 0xff);
4387    * }
4388    */
4389   add_parse_predicates();
4390   C->set_has_loops(true);
4391 
4392   RegionNode* head = new RegionNode(3);
4393   head->init_req(1, control());
4394   gvn().set_type(head, Type::CONTROL);
4395   record_for_igvn(head);
4396 
4397   Node* i_byte = new PhiNode(head, TypeInt::INT);
4398   i_byte->init_req(1, intcon(0));
4399   gvn().set_type(i_byte, TypeInt::INT);
4400   record_for_igvn(i_byte);
4401 
4402   Node* i_char = new PhiNode(head, TypeInt::INT);
4403   i_char->init_req(1, start);
4404   gvn().set_type(i_char, TypeInt::INT);
4405   record_for_igvn(i_char);
4406 
4407   Node* mem = PhiNode::make(head, memory(TypeAryPtr::BYTES), Type::MEMORY, TypeAryPtr::BYTES);
4408   gvn().set_type(mem, Type::MEMORY);
4409   record_for_igvn(mem);
4410   set_control(head);
4411   set_memory(mem, TypeAryPtr::BYTES);
4412   Node* ch = load_array_element(src, i_byte, TypeAryPtr::BYTES, /* set_ctrl */ true);
4413   Node* st = store_to_memory(control(), array_element_address(dst, i_char, T_BYTE),
4414                              AndI(ch, intcon(0xff)), T_CHAR, MemNode::unordered, false,
4415                              false, true /* mismatched */);
4416 
4417   IfNode* iff = create_and_map_if(head, Bool(CmpI(i_byte, count), BoolTest::lt), PROB_FAIR, COUNT_UNKNOWN);
4418   head->init_req(2, IfTrue(iff));
4419   mem->init_req(2, st);
4420   i_byte->init_req(2, AddI(i_byte, intcon(1)));
4421   i_char->init_req(2, AddI(i_char, intcon(2)));
4422 
4423   set_control(IfFalse(iff));
4424   set_memory(st, TypeAryPtr::BYTES);
4425 }
4426 
4427 Node* GraphKit::make_constant_from_field(ciField* field, Node* obj) {
4428   if (!field->is_constant()) {
4429     return nullptr; // Field not marked as constant.
4430   }
4431   ciInstance* holder = nullptr;
4432   if (!field->is_static()) {
4433     ciObject* const_oop = obj->bottom_type()->is_oopptr()->const_oop();
4434     if (const_oop != nullptr && const_oop->is_instance()) {
4435       holder = const_oop->as_instance();
4436     }
4437   }
4438   const Type* con_type = Type::make_constant_from_field(field, holder, field->layout_type(),
4439                                                         /*is_unsigned_load=*/false);
4440   if (con_type != nullptr) {
4441     return makecon(con_type);
4442   }
4443   return nullptr;
4444 }
4445 
4446 Node* GraphKit::maybe_narrow_object_type(Node* obj, ciKlass* type) {
4447   const TypeOopPtr* obj_type = obj->bottom_type()->isa_oopptr();
4448   const TypeOopPtr* sig_type = TypeOopPtr::make_from_klass(type);
4449   if (obj_type != nullptr && sig_type->is_loaded() && !obj_type->higher_equal(sig_type)) {
4450     const Type* narrow_obj_type = obj_type->filter_speculative(sig_type); // keep speculative part
4451     Node* casted_obj = gvn().transform(new CheckCastPPNode(control(), obj, narrow_obj_type));
4452     return casted_obj;
4453   }
4454   return obj;
4455 }