1 /*
   2  * Copyright (c) 2001, 2024, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "ci/ciUtilities.hpp"
  27 #include "classfile/javaClasses.hpp"
  28 #include "ci/ciObjArray.hpp"
  29 #include "asm/register.hpp"
  30 #include "compiler/compileLog.hpp"
  31 #include "gc/shared/barrierSet.hpp"
  32 #include "gc/shared/c2/barrierSetC2.hpp"
  33 #include "interpreter/interpreter.hpp"
  34 #include "memory/resourceArea.hpp"
  35 #include "opto/addnode.hpp"
  36 #include "opto/castnode.hpp"
  37 #include "opto/convertnode.hpp"
  38 #include "opto/graphKit.hpp"
  39 #include "opto/idealKit.hpp"
  40 #include "opto/intrinsicnode.hpp"
  41 #include "opto/locknode.hpp"
  42 #include "opto/machnode.hpp"
  43 #include "opto/opaquenode.hpp"
  44 #include "opto/parse.hpp"
  45 #include "opto/rootnode.hpp"
  46 #include "opto/runtime.hpp"
  47 #include "opto/subtypenode.hpp"
  48 #include "runtime/deoptimization.hpp"
  49 #include "runtime/sharedRuntime.hpp"
  50 #include "utilities/bitMap.inline.hpp"
  51 #include "utilities/powerOfTwo.hpp"
  52 #include "utilities/growableArray.hpp"
  53 
  54 //----------------------------GraphKit-----------------------------------------
  55 // Main utility constructor.
  56 GraphKit::GraphKit(JVMState* jvms)
  57   : Phase(Phase::Parser),
  58     _env(C->env()),
  59     _gvn(*C->initial_gvn()),
  60     _barrier_set(BarrierSet::barrier_set()->barrier_set_c2())
  61 {
  62   _exceptions = jvms->map()->next_exception();
  63   if (_exceptions != nullptr)  jvms->map()->set_next_exception(nullptr);
  64   set_jvms(jvms);
  65 }
  66 
  67 // Private constructor for parser.
  68 GraphKit::GraphKit()
  69   : Phase(Phase::Parser),
  70     _env(C->env()),
  71     _gvn(*C->initial_gvn()),
  72     _barrier_set(BarrierSet::barrier_set()->barrier_set_c2())
  73 {
  74   _exceptions = nullptr;
  75   set_map(nullptr);
  76   debug_only(_sp = -99);
  77   debug_only(set_bci(-99));
  78 }
  79 
  80 
  81 
  82 //---------------------------clean_stack---------------------------------------
  83 // Clear away rubbish from the stack area of the JVM state.
  84 // This destroys any arguments that may be waiting on the stack.
  85 void GraphKit::clean_stack(int from_sp) {
  86   SafePointNode* map      = this->map();
  87   JVMState*      jvms     = this->jvms();
  88   int            stk_size = jvms->stk_size();
  89   int            stkoff   = jvms->stkoff();
  90   Node*          top      = this->top();
  91   for (int i = from_sp; i < stk_size; i++) {
  92     if (map->in(stkoff + i) != top) {
  93       map->set_req(stkoff + i, top);
  94     }
  95   }
  96 }
  97 
  98 
  99 //--------------------------------sync_jvms-----------------------------------
 100 // Make sure our current jvms agrees with our parse state.
 101 JVMState* GraphKit::sync_jvms() const {
 102   JVMState* jvms = this->jvms();
 103   jvms->set_bci(bci());       // Record the new bci in the JVMState
 104   jvms->set_sp(sp());         // Record the new sp in the JVMState
 105   assert(jvms_in_sync(), "jvms is now in sync");
 106   return jvms;
 107 }
 108 
 109 //--------------------------------sync_jvms_for_reexecute---------------------
 110 // Make sure our current jvms agrees with our parse state.  This version
 111 // uses the reexecute_sp for reexecuting bytecodes.
 112 JVMState* GraphKit::sync_jvms_for_reexecute() {
 113   JVMState* jvms = this->jvms();
 114   jvms->set_bci(bci());          // Record the new bci in the JVMState
 115   jvms->set_sp(reexecute_sp());  // Record the new sp in the JVMState
 116   return jvms;
 117 }
 118 
 119 #ifdef ASSERT
 120 bool GraphKit::jvms_in_sync() const {
 121   Parse* parse = is_Parse();
 122   if (parse == nullptr) {
 123     if (bci() !=      jvms()->bci())          return false;
 124     if (sp()  != (int)jvms()->sp())           return false;
 125     return true;
 126   }
 127   if (jvms()->method() != parse->method())    return false;
 128   if (jvms()->bci()    != parse->bci())       return false;
 129   int jvms_sp = jvms()->sp();
 130   if (jvms_sp          != parse->sp())        return false;
 131   int jvms_depth = jvms()->depth();
 132   if (jvms_depth       != parse->depth())     return false;
 133   return true;
 134 }
 135 
 136 // Local helper checks for special internal merge points
 137 // used to accumulate and merge exception states.
 138 // They are marked by the region's in(0) edge being the map itself.
 139 // Such merge points must never "escape" into the parser at large,
 140 // until they have been handed to gvn.transform.
 141 static bool is_hidden_merge(Node* reg) {
 142   if (reg == nullptr)  return false;
 143   if (reg->is_Phi()) {
 144     reg = reg->in(0);
 145     if (reg == nullptr)  return false;
 146   }
 147   return reg->is_Region() && reg->in(0) != nullptr && reg->in(0)->is_Root();
 148 }
 149 
 150 void GraphKit::verify_map() const {
 151   if (map() == nullptr)  return;  // null map is OK
 152   assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
 153   assert(!map()->has_exceptions(),    "call add_exception_states_from 1st");
 154   assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
 155 }
 156 
 157 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
 158   assert(ex_map->next_exception() == nullptr, "not already part of a chain");
 159   assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
 160 }
 161 #endif
 162 
 163 //---------------------------stop_and_kill_map---------------------------------
 164 // Set _map to null, signalling a stop to further bytecode execution.
 165 // First smash the current map's control to a constant, to mark it dead.
 166 void GraphKit::stop_and_kill_map() {
 167   SafePointNode* dead_map = stop();
 168   if (dead_map != nullptr) {
 169     dead_map->disconnect_inputs(C); // Mark the map as killed.
 170     assert(dead_map->is_killed(), "must be so marked");
 171   }
 172 }
 173 
 174 
 175 //--------------------------------stopped--------------------------------------
 176 // Tell if _map is null, or control is top.
 177 bool GraphKit::stopped() {
 178   if (map() == nullptr)        return true;
 179   else if (control() == top()) return true;
 180   else                         return false;
 181 }
 182 
 183 
 184 //-----------------------------has_exception_handler----------------------------------
 185 // Tell if this method or any caller method has exception handlers.
 186 bool GraphKit::has_exception_handler() {
 187   for (JVMState* jvmsp = jvms(); jvmsp != nullptr; jvmsp = jvmsp->caller()) {
 188     if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
 189       return true;
 190     }
 191   }
 192   return false;
 193 }
 194 
 195 //------------------------------save_ex_oop------------------------------------
 196 // Save an exception without blowing stack contents or other JVM state.
 197 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
 198   assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
 199   ex_map->add_req(ex_oop);
 200   debug_only(verify_exception_state(ex_map));
 201 }
 202 
 203 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
 204   assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
 205   Node* ex_oop = ex_map->in(ex_map->req()-1);
 206   if (clear_it)  ex_map->del_req(ex_map->req()-1);
 207   return ex_oop;
 208 }
 209 
 210 //-----------------------------saved_ex_oop------------------------------------
 211 // Recover a saved exception from its map.
 212 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
 213   return common_saved_ex_oop(ex_map, false);
 214 }
 215 
 216 //--------------------------clear_saved_ex_oop---------------------------------
 217 // Erase a previously saved exception from its map.
 218 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
 219   return common_saved_ex_oop(ex_map, true);
 220 }
 221 
 222 #ifdef ASSERT
 223 //---------------------------has_saved_ex_oop----------------------------------
 224 // Erase a previously saved exception from its map.
 225 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
 226   return ex_map->req() == ex_map->jvms()->endoff()+1;
 227 }
 228 #endif
 229 
 230 //-------------------------make_exception_state--------------------------------
 231 // Turn the current JVM state into an exception state, appending the ex_oop.
 232 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
 233   sync_jvms();
 234   SafePointNode* ex_map = stop();  // do not manipulate this map any more
 235   set_saved_ex_oop(ex_map, ex_oop);
 236   return ex_map;
 237 }
 238 
 239 
 240 //--------------------------add_exception_state--------------------------------
 241 // Add an exception to my list of exceptions.
 242 void GraphKit::add_exception_state(SafePointNode* ex_map) {
 243   if (ex_map == nullptr || ex_map->control() == top()) {
 244     return;
 245   }
 246 #ifdef ASSERT
 247   verify_exception_state(ex_map);
 248   if (has_exceptions()) {
 249     assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
 250   }
 251 #endif
 252 
 253   // If there is already an exception of exactly this type, merge with it.
 254   // In particular, null-checks and other low-level exceptions common up here.
 255   Node*       ex_oop  = saved_ex_oop(ex_map);
 256   const Type* ex_type = _gvn.type(ex_oop);
 257   if (ex_oop == top()) {
 258     // No action needed.
 259     return;
 260   }
 261   assert(ex_type->isa_instptr(), "exception must be an instance");
 262   for (SafePointNode* e2 = _exceptions; e2 != nullptr; e2 = e2->next_exception()) {
 263     const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
 264     // We check sp also because call bytecodes can generate exceptions
 265     // both before and after arguments are popped!
 266     if (ex_type2 == ex_type
 267         && e2->_jvms->sp() == ex_map->_jvms->sp()) {
 268       combine_exception_states(ex_map, e2);
 269       return;
 270     }
 271   }
 272 
 273   // No pre-existing exception of the same type.  Chain it on the list.
 274   push_exception_state(ex_map);
 275 }
 276 
 277 //-----------------------add_exception_states_from-----------------------------
 278 void GraphKit::add_exception_states_from(JVMState* jvms) {
 279   SafePointNode* ex_map = jvms->map()->next_exception();
 280   if (ex_map != nullptr) {
 281     jvms->map()->set_next_exception(nullptr);
 282     for (SafePointNode* next_map; ex_map != nullptr; ex_map = next_map) {
 283       next_map = ex_map->next_exception();
 284       ex_map->set_next_exception(nullptr);
 285       add_exception_state(ex_map);
 286     }
 287   }
 288 }
 289 
 290 //-----------------------transfer_exceptions_into_jvms-------------------------
 291 JVMState* GraphKit::transfer_exceptions_into_jvms() {
 292   if (map() == nullptr) {
 293     // We need a JVMS to carry the exceptions, but the map has gone away.
 294     // Create a scratch JVMS, cloned from any of the exception states...
 295     if (has_exceptions()) {
 296       _map = _exceptions;
 297       _map = clone_map();
 298       _map->set_next_exception(nullptr);
 299       clear_saved_ex_oop(_map);
 300       debug_only(verify_map());
 301     } else {
 302       // ...or created from scratch
 303       JVMState* jvms = new (C) JVMState(_method, nullptr);
 304       jvms->set_bci(_bci);
 305       jvms->set_sp(_sp);
 306       jvms->set_map(new SafePointNode(TypeFunc::Parms, jvms));
 307       set_jvms(jvms);
 308       for (uint i = 0; i < map()->req(); i++)  map()->init_req(i, top());
 309       set_all_memory(top());
 310       while (map()->req() < jvms->endoff())  map()->add_req(top());
 311     }
 312     // (This is a kludge, in case you didn't notice.)
 313     set_control(top());
 314   }
 315   JVMState* jvms = sync_jvms();
 316   assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
 317   jvms->map()->set_next_exception(_exceptions);
 318   _exceptions = nullptr;   // done with this set of exceptions
 319   return jvms;
 320 }
 321 
 322 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
 323   assert(is_hidden_merge(dstphi), "must be a special merge node");
 324   assert(is_hidden_merge(srcphi), "must be a special merge node");
 325   uint limit = srcphi->req();
 326   for (uint i = PhiNode::Input; i < limit; i++) {
 327     dstphi->add_req(srcphi->in(i));
 328   }
 329 }
 330 static inline void add_one_req(Node* dstphi, Node* src) {
 331   assert(is_hidden_merge(dstphi), "must be a special merge node");
 332   assert(!is_hidden_merge(src), "must not be a special merge node");
 333   dstphi->add_req(src);
 334 }
 335 
 336 //-----------------------combine_exception_states------------------------------
 337 // This helper function combines exception states by building phis on a
 338 // specially marked state-merging region.  These regions and phis are
 339 // untransformed, and can build up gradually.  The region is marked by
 340 // having a control input of its exception map, rather than null.  Such
 341 // regions do not appear except in this function, and in use_exception_state.
 342 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
 343   if (failing_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, Compile::AliasIdxRaw, 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   bool must_throw = true;
 532 
 533   // If this particular condition has not yet happened at this
 534   // bytecode, then use the uncommon trap mechanism, and allow for
 535   // a future recompilation if several traps occur here.
 536   // If the throw is hot, try to use a more complicated inline mechanism
 537   // which keeps execution inside the compiled code.
 538   bool treat_throw_as_hot = false;
 539   ciMethodData* md = method()->method_data();
 540 
 541   if (ProfileTraps) {
 542     if (too_many_traps(reason)) {
 543       treat_throw_as_hot = true;
 544     }
 545     // (If there is no MDO at all, assume it is early in
 546     // execution, and that any deopts are part of the
 547     // startup transient, and don't need to be remembered.)
 548 
 549     // Also, if there is a local exception handler, treat all throws
 550     // as hot if there has been at least one in this method.
 551     if (C->trap_count(reason) != 0
 552         && method()->method_data()->trap_count(reason) != 0
 553         && has_exception_handler()) {
 554         treat_throw_as_hot = true;
 555     }
 556   }
 557 
 558   // If this throw happens frequently, an uncommon trap might cause
 559   // a performance pothole.  If there is a local exception handler,
 560   // and if this particular bytecode appears to be deoptimizing often,
 561   // let us handle the throw inline, with a preconstructed instance.
 562   // Note:   If the deopt count has blown up, the uncommon trap
 563   // runtime is going to flush this nmethod, not matter what.
 564   if (treat_throw_as_hot && method()->can_omit_stack_trace()) {
 565     // If the throw is local, we use a pre-existing instance and
 566     // punt on the backtrace.  This would lead to a missing backtrace
 567     // (a repeat of 4292742) if the backtrace object is ever asked
 568     // for its backtrace.
 569     // Fixing this remaining case of 4292742 requires some flavor of
 570     // escape analysis.  Leave that for the future.
 571     ciInstance* ex_obj = nullptr;
 572     switch (reason) {
 573     case Deoptimization::Reason_null_check:
 574       ex_obj = env()->NullPointerException_instance();
 575       break;
 576     case Deoptimization::Reason_div0_check:
 577       ex_obj = env()->ArithmeticException_instance();
 578       break;
 579     case Deoptimization::Reason_range_check:
 580       ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
 581       break;
 582     case Deoptimization::Reason_class_check:
 583       ex_obj = env()->ClassCastException_instance();
 584       break;
 585     case Deoptimization::Reason_array_check:
 586       ex_obj = env()->ArrayStoreException_instance();
 587       break;
 588     default:
 589       break;
 590     }
 591     if (failing()) { stop(); return; }  // exception allocation might fail
 592     if (ex_obj != nullptr) {
 593       if (env()->jvmti_can_post_on_exceptions()) {
 594         // check if we must post exception events, take uncommon trap if so
 595         uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
 596         // here if should_post_on_exceptions is false
 597         // continue on with the normal codegen
 598       }
 599 
 600       // Cheat with a preallocated exception object.
 601       if (C->log() != nullptr)
 602         C->log()->elem("hot_throw preallocated='1' reason='%s'",
 603                        Deoptimization::trap_reason_name(reason));
 604       const TypeInstPtr* ex_con  = TypeInstPtr::make(ex_obj);
 605       Node*              ex_node = _gvn.transform(ConNode::make(ex_con));
 606 
 607       // Clear the detail message of the preallocated exception object.
 608       // Weblogic sometimes mutates the detail message of exceptions
 609       // using reflection.
 610       int offset = java_lang_Throwable::get_detailMessage_offset();
 611       const TypePtr* adr_typ = ex_con->add_offset(offset);
 612 
 613       Node *adr = basic_plus_adr(ex_node, ex_node, offset);
 614       const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
 615       Node *store = access_store_at(ex_node, adr, adr_typ, null(), val_type, T_OBJECT, IN_HEAP);
 616 
 617       if (!method()->has_exception_handlers()) {
 618         // We don't need to preserve the stack if there's no handler as the entire frame is going to be popped anyway.
 619         // This prevents issues with exception handling and late inlining.
 620         set_sp(0);
 621         clean_stack(0);
 622       }
 623 
 624       add_exception_state(make_exception_state(ex_node));
 625       return;
 626     }
 627   }
 628 
 629   // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
 630   // It won't be much cheaper than bailing to the interp., since we'll
 631   // have to pass up all the debug-info, and the runtime will have to
 632   // create the stack trace.
 633 
 634   // Usual case:  Bail to interpreter.
 635   // Reserve the right to recompile if we haven't seen anything yet.
 636 
 637   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? C->method() : nullptr;
 638   Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
 639   if (treat_throw_as_hot
 640       && (method()->method_data()->trap_recompiled_at(bci(), m)
 641           || C->too_many_traps(reason))) {
 642     // We cannot afford to take more traps here.  Suffer in the interpreter.
 643     if (C->log() != nullptr)
 644       C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
 645                      Deoptimization::trap_reason_name(reason),
 646                      C->trap_count(reason));
 647     action = Deoptimization::Action_none;
 648   }
 649 
 650   // "must_throw" prunes the JVM state to include only the stack, if there
 651   // are no local exception handlers.  This should cut down on register
 652   // allocation time and code size, by drastically reducing the number
 653   // of in-edges on the call to the uncommon trap.
 654 
 655   uncommon_trap(reason, action, (ciKlass*)nullptr, (char*)nullptr, must_throw);
 656 }
 657 
 658 
 659 //----------------------------PreserveJVMState---------------------------------
 660 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
 661   debug_only(kit->verify_map());
 662   _kit    = kit;
 663   _map    = kit->map();   // preserve the map
 664   _sp     = kit->sp();
 665   kit->set_map(clone_map ? kit->clone_map() : nullptr);
 666 #ifdef ASSERT
 667   _bci    = kit->bci();
 668   Parse* parser = kit->is_Parse();
 669   int block = (parser == nullptr || parser->block() == nullptr) ? -1 : parser->block()->rpo();
 670   _block  = block;
 671 #endif
 672 }
 673 PreserveJVMState::~PreserveJVMState() {
 674   GraphKit* kit = _kit;
 675 #ifdef ASSERT
 676   assert(kit->bci() == _bci, "bci must not shift");
 677   Parse* parser = kit->is_Parse();
 678   int block = (parser == nullptr || parser->block() == nullptr) ? -1 : parser->block()->rpo();
 679   assert(block == _block,    "block must not shift");
 680 #endif
 681   kit->set_map(_map);
 682   kit->set_sp(_sp);
 683 }
 684 
 685 
 686 //-----------------------------BuildCutout-------------------------------------
 687 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
 688   : PreserveJVMState(kit)
 689 {
 690   assert(p->is_Con() || p->is_Bool(), "test must be a bool");
 691   SafePointNode* outer_map = _map;   // preserved map is caller's
 692   SafePointNode* inner_map = kit->map();
 693   IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
 694   outer_map->set_control(kit->gvn().transform( new IfTrueNode(iff) ));
 695   inner_map->set_control(kit->gvn().transform( new IfFalseNode(iff) ));
 696 }
 697 BuildCutout::~BuildCutout() {
 698   GraphKit* kit = _kit;
 699   assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
 700 }
 701 
 702 //---------------------------PreserveReexecuteState----------------------------
 703 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
 704   assert(!kit->stopped(), "must call stopped() before");
 705   _kit    =    kit;
 706   _sp     =    kit->sp();
 707   _reexecute = kit->jvms()->_reexecute;
 708 }
 709 PreserveReexecuteState::~PreserveReexecuteState() {
 710   if (_kit->stopped()) return;
 711   _kit->jvms()->_reexecute = _reexecute;
 712   _kit->set_sp(_sp);
 713 }
 714 
 715 //------------------------------clone_map--------------------------------------
 716 // Implementation of PreserveJVMState
 717 //
 718 // Only clone_map(...) here. If this function is only used in the
 719 // PreserveJVMState class we may want to get rid of this extra
 720 // function eventually and do it all there.
 721 
 722 SafePointNode* GraphKit::clone_map() {
 723   if (map() == nullptr)  return nullptr;
 724 
 725   // Clone the memory edge first
 726   Node* mem = MergeMemNode::make(map()->memory());
 727   gvn().set_type_bottom(mem);
 728 
 729   SafePointNode *clonemap = (SafePointNode*)map()->clone();
 730   JVMState* jvms = this->jvms();
 731   JVMState* clonejvms = jvms->clone_shallow(C);
 732   clonemap->set_memory(mem);
 733   clonemap->set_jvms(clonejvms);
 734   clonejvms->set_map(clonemap);
 735   record_for_igvn(clonemap);
 736   gvn().set_type_bottom(clonemap);
 737   return clonemap;
 738 }
 739 
 740 //-----------------------------destruct_map_clone------------------------------
 741 //
 742 // Order of destruct is important to increase the likelyhood that memory can be re-used. We need
 743 // to destruct/free/delete in the exact opposite order as clone_map().
 744 void GraphKit::destruct_map_clone(SafePointNode* sfp) {
 745   if (sfp == nullptr) return;
 746 
 747   Node* mem = sfp->memory();
 748   JVMState* jvms = sfp->jvms();
 749 
 750   if (jvms != nullptr) {
 751     delete jvms;
 752   }
 753 
 754   remove_for_igvn(sfp);
 755   gvn().clear_type(sfp);
 756   sfp->destruct(&_gvn);
 757 
 758   if (mem != nullptr) {
 759     gvn().clear_type(mem);
 760     mem->destruct(&_gvn);
 761   }
 762 }
 763 
 764 //-----------------------------set_map_clone-----------------------------------
 765 void GraphKit::set_map_clone(SafePointNode* m) {
 766   _map = m;
 767   _map = clone_map();
 768   _map->set_next_exception(nullptr);
 769   debug_only(verify_map());
 770 }
 771 
 772 
 773 //----------------------------kill_dead_locals---------------------------------
 774 // Detect any locals which are known to be dead, and force them to top.
 775 void GraphKit::kill_dead_locals() {
 776   // Consult the liveness information for the locals.  If any
 777   // of them are unused, then they can be replaced by top().  This
 778   // should help register allocation time and cut down on the size
 779   // of the deoptimization information.
 780 
 781   // This call is made from many of the bytecode handling
 782   // subroutines called from the Big Switch in do_one_bytecode.
 783   // Every bytecode which might include a slow path is responsible
 784   // for killing its dead locals.  The more consistent we
 785   // are about killing deads, the fewer useless phis will be
 786   // constructed for them at various merge points.
 787 
 788   // bci can be -1 (InvocationEntryBci).  We return the entry
 789   // liveness for the method.
 790 
 791   if (method() == nullptr || method()->code_size() == 0) {
 792     // We are building a graph for a call to a native method.
 793     // All locals are live.
 794     return;
 795   }
 796 
 797   ResourceMark rm;
 798 
 799   // Consult the liveness information for the locals.  If any
 800   // of them are unused, then they can be replaced by top().  This
 801   // should help register allocation time and cut down on the size
 802   // of the deoptimization information.
 803   MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
 804 
 805   int len = (int)live_locals.size();
 806   assert(len <= jvms()->loc_size(), "too many live locals");
 807   for (int local = 0; local < len; local++) {
 808     if (!live_locals.at(local)) {
 809       set_local(local, top());
 810     }
 811   }
 812 }
 813 
 814 #ifdef ASSERT
 815 //-------------------------dead_locals_are_killed------------------------------
 816 // Return true if all dead locals are set to top in the map.
 817 // Used to assert "clean" debug info at various points.
 818 bool GraphKit::dead_locals_are_killed() {
 819   if (method() == nullptr || method()->code_size() == 0) {
 820     // No locals need to be dead, so all is as it should be.
 821     return true;
 822   }
 823 
 824   // Make sure somebody called kill_dead_locals upstream.
 825   ResourceMark rm;
 826   for (JVMState* jvms = this->jvms(); jvms != nullptr; jvms = jvms->caller()) {
 827     if (jvms->loc_size() == 0)  continue;  // no locals to consult
 828     SafePointNode* map = jvms->map();
 829     ciMethod* method = jvms->method();
 830     int       bci    = jvms->bci();
 831     if (jvms == this->jvms()) {
 832       bci = this->bci();  // it might not yet be synched
 833     }
 834     MethodLivenessResult live_locals = method->liveness_at_bci(bci);
 835     int len = (int)live_locals.size();
 836     if (!live_locals.is_valid() || len == 0)
 837       // This method is trivial, or is poisoned by a breakpoint.
 838       return true;
 839     assert(len == jvms->loc_size(), "live map consistent with locals map");
 840     for (int local = 0; local < len; local++) {
 841       if (!live_locals.at(local) && map->local(jvms, local) != top()) {
 842         if (PrintMiscellaneous && (Verbose || WizardMode)) {
 843           tty->print_cr("Zombie local %d: ", local);
 844           jvms->dump();
 845         }
 846         return false;
 847       }
 848     }
 849   }
 850   return true;
 851 }
 852 
 853 #endif //ASSERT
 854 
 855 // Helper function for enforcing certain bytecodes to reexecute if deoptimization happens.
 856 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
 857   ciMethod* cur_method = jvms->method();
 858   int       cur_bci   = jvms->bci();
 859   if (cur_method != nullptr && cur_bci != InvocationEntryBci) {
 860     Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
 861     return Interpreter::bytecode_should_reexecute(code) ||
 862            (is_anewarray && code == Bytecodes::_multianewarray);
 863     // Reexecute _multianewarray bytecode which was replaced with
 864     // sequence of [a]newarray. See Parse::do_multianewarray().
 865     //
 866     // Note: interpreter should not have it set since this optimization
 867     // is limited by dimensions and guarded by flag so in some cases
 868     // multianewarray() runtime calls will be generated and
 869     // the bytecode should not be reexecutes (stack will not be reset).
 870   } else {
 871     return false;
 872   }
 873 }
 874 
 875 // Helper function for adding JVMState and debug information to node
 876 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
 877   // Add the safepoint edges to the call (or other safepoint).
 878 
 879   // Make sure dead locals are set to top.  This
 880   // should help register allocation time and cut down on the size
 881   // of the deoptimization information.
 882   assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
 883 
 884   // Walk the inline list to fill in the correct set of JVMState's
 885   // Also fill in the associated edges for each JVMState.
 886 
 887   // If the bytecode needs to be reexecuted we need to put
 888   // the arguments back on the stack.
 889   const bool should_reexecute = jvms()->should_reexecute();
 890   JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
 891 
 892   // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
 893   // undefined if the bci is different.  This is normal for Parse but it
 894   // should not happen for LibraryCallKit because only one bci is processed.
 895   assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
 896          "in LibraryCallKit the reexecute bit should not change");
 897 
 898   // If we are guaranteed to throw, we can prune everything but the
 899   // input to the current bytecode.
 900   bool can_prune_locals = false;
 901   uint stack_slots_not_pruned = 0;
 902   int inputs = 0, depth = 0;
 903   if (must_throw) {
 904     assert(method() == youngest_jvms->method(), "sanity");
 905     if (compute_stack_effects(inputs, depth)) {
 906       can_prune_locals = true;
 907       stack_slots_not_pruned = inputs;
 908     }
 909   }
 910 
 911   if (env()->should_retain_local_variables()) {
 912     // At any safepoint, this method can get breakpointed, which would
 913     // then require an immediate deoptimization.
 914     can_prune_locals = false;  // do not prune locals
 915     stack_slots_not_pruned = 0;
 916   }
 917 
 918   // do not scribble on the input jvms
 919   JVMState* out_jvms = youngest_jvms->clone_deep(C);
 920   call->set_jvms(out_jvms); // Start jvms list for call node
 921 
 922   // For a known set of bytecodes, the interpreter should reexecute them if
 923   // deoptimization happens. We set the reexecute state for them here
 924   if (out_jvms->is_reexecute_undefined() && //don't change if already specified
 925       should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
 926 #ifdef ASSERT
 927     int inputs = 0, not_used; // initialized by GraphKit::compute_stack_effects()
 928     assert(method() == youngest_jvms->method(), "sanity");
 929     assert(compute_stack_effects(inputs, not_used), "unknown bytecode: %s", Bytecodes::name(java_bc()));
 930     assert(out_jvms->sp() >= (uint)inputs, "not enough operands for reexecution");
 931 #endif // ASSERT
 932     out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
 933   }
 934 
 935   // Presize the call:
 936   DEBUG_ONLY(uint non_debug_edges = call->req());
 937   call->add_req_batch(top(), youngest_jvms->debug_depth());
 938   assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
 939 
 940   // Set up edges so that the call looks like this:
 941   //  Call [state:] ctl io mem fptr retadr
 942   //       [parms:] parm0 ... parmN
 943   //       [root:]  loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 944   //    [...mid:]   loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
 945   //       [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 946   // Note that caller debug info precedes callee debug info.
 947 
 948   // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
 949   uint debug_ptr = call->req();
 950 
 951   // Loop over the map input edges associated with jvms, add them
 952   // to the call node, & reset all offsets to match call node array.
 953   for (JVMState* in_jvms = youngest_jvms; in_jvms != nullptr; ) {
 954     uint debug_end   = debug_ptr;
 955     uint debug_start = debug_ptr - in_jvms->debug_size();
 956     debug_ptr = debug_start;  // back up the ptr
 957 
 958     uint p = debug_start;  // walks forward in [debug_start, debug_end)
 959     uint j, k, l;
 960     SafePointNode* in_map = in_jvms->map();
 961     out_jvms->set_map(call);
 962 
 963     if (can_prune_locals) {
 964       assert(in_jvms->method() == out_jvms->method(), "sanity");
 965       // If the current throw can reach an exception handler in this JVMS,
 966       // then we must keep everything live that can reach that handler.
 967       // As a quick and dirty approximation, we look for any handlers at all.
 968       if (in_jvms->method()->has_exception_handlers()) {
 969         can_prune_locals = false;
 970       }
 971     }
 972 
 973     // Add the Locals
 974     k = in_jvms->locoff();
 975     l = in_jvms->loc_size();
 976     out_jvms->set_locoff(p);
 977     if (!can_prune_locals) {
 978       for (j = 0; j < l; j++)
 979         call->set_req(p++, in_map->in(k+j));
 980     } else {
 981       p += l;  // already set to top above by add_req_batch
 982     }
 983 
 984     // Add the Expression Stack
 985     k = in_jvms->stkoff();
 986     l = in_jvms->sp();
 987     out_jvms->set_stkoff(p);
 988     if (!can_prune_locals) {
 989       for (j = 0; j < l; j++)
 990         call->set_req(p++, in_map->in(k+j));
 991     } else if (can_prune_locals && stack_slots_not_pruned != 0) {
 992       // Divide stack into {S0,...,S1}, where S0 is set to top.
 993       uint s1 = stack_slots_not_pruned;
 994       stack_slots_not_pruned = 0;  // for next iteration
 995       if (s1 > l)  s1 = l;
 996       uint s0 = l - s1;
 997       p += s0;  // skip the tops preinstalled by add_req_batch
 998       for (j = s0; j < l; j++)
 999         call->set_req(p++, in_map->in(k+j));
1000     } else {
1001       p += l;  // already set to top above by add_req_batch
1002     }
1003 
1004     // Add the Monitors
1005     k = in_jvms->monoff();
1006     l = in_jvms->mon_size();
1007     out_jvms->set_monoff(p);
1008     for (j = 0; j < l; j++)
1009       call->set_req(p++, in_map->in(k+j));
1010 
1011     // Copy any scalar object fields.
1012     k = in_jvms->scloff();
1013     l = in_jvms->scl_size();
1014     out_jvms->set_scloff(p);
1015     for (j = 0; j < l; j++)
1016       call->set_req(p++, in_map->in(k+j));
1017 
1018     // Finish the new jvms.
1019     out_jvms->set_endoff(p);
1020 
1021     assert(out_jvms->endoff()     == debug_end,             "fill ptr must match");
1022     assert(out_jvms->depth()      == in_jvms->depth(),      "depth must match");
1023     assert(out_jvms->loc_size()   == in_jvms->loc_size(),   "size must match");
1024     assert(out_jvms->mon_size()   == in_jvms->mon_size(),   "size must match");
1025     assert(out_jvms->scl_size()   == in_jvms->scl_size(),   "size must match");
1026     assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
1027 
1028     // Update the two tail pointers in parallel.
1029     out_jvms = out_jvms->caller();
1030     in_jvms  = in_jvms->caller();
1031   }
1032 
1033   assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
1034 
1035   // Test the correctness of JVMState::debug_xxx accessors:
1036   assert(call->jvms()->debug_start() == non_debug_edges, "");
1037   assert(call->jvms()->debug_end()   == call->req(), "");
1038   assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
1039 }
1040 
1041 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
1042   Bytecodes::Code code = java_bc();
1043   if (code == Bytecodes::_wide) {
1044     code = method()->java_code_at_bci(bci() + 1);
1045   }
1046 
1047   if (code != Bytecodes::_illegal) {
1048     depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1049   }
1050 
1051   auto rsize = [&]() {
1052     assert(code != Bytecodes::_illegal, "code is illegal!");
1053     BasicType rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1054     return (rtype < T_CONFLICT) ? type2size[rtype] : 0;
1055   };
1056 
1057   switch (code) {
1058   case Bytecodes::_illegal:
1059     return false;
1060 
1061   case Bytecodes::_ldc:
1062   case Bytecodes::_ldc_w:
1063   case Bytecodes::_ldc2_w:
1064     inputs = 0;
1065     break;
1066 
1067   case Bytecodes::_dup:         inputs = 1;  break;
1068   case Bytecodes::_dup_x1:      inputs = 2;  break;
1069   case Bytecodes::_dup_x2:      inputs = 3;  break;
1070   case Bytecodes::_dup2:        inputs = 2;  break;
1071   case Bytecodes::_dup2_x1:     inputs = 3;  break;
1072   case Bytecodes::_dup2_x2:     inputs = 4;  break;
1073   case Bytecodes::_swap:        inputs = 2;  break;
1074   case Bytecodes::_arraylength: inputs = 1;  break;
1075 
1076   case Bytecodes::_getstatic:
1077   case Bytecodes::_putstatic:
1078   case Bytecodes::_getfield:
1079   case Bytecodes::_putfield:
1080     {
1081       bool ignored_will_link;
1082       ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1083       int      size  = field->type()->size();
1084       bool is_get = (depth >= 0), is_static = (depth & 1);
1085       inputs = (is_static ? 0 : 1);
1086       if (is_get) {
1087         depth = size - inputs;
1088       } else {
1089         inputs += size;        // putxxx pops the value from the stack
1090         depth = - inputs;
1091       }
1092     }
1093     break;
1094 
1095   case Bytecodes::_invokevirtual:
1096   case Bytecodes::_invokespecial:
1097   case Bytecodes::_invokestatic:
1098   case Bytecodes::_invokedynamic:
1099   case Bytecodes::_invokeinterface:
1100     {
1101       bool ignored_will_link;
1102       ciSignature* declared_signature = nullptr;
1103       ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1104       assert(declared_signature != nullptr, "cannot be null");
1105       inputs   = declared_signature->arg_size_for_bc(code);
1106       int size = declared_signature->return_type()->size();
1107       depth = size - inputs;
1108     }
1109     break;
1110 
1111   case Bytecodes::_multianewarray:
1112     {
1113       ciBytecodeStream iter(method());
1114       iter.reset_to_bci(bci());
1115       iter.next();
1116       inputs = iter.get_dimensions();
1117       assert(rsize() == 1, "");
1118       depth = 1 - inputs;
1119     }
1120     break;
1121 
1122   case Bytecodes::_ireturn:
1123   case Bytecodes::_lreturn:
1124   case Bytecodes::_freturn:
1125   case Bytecodes::_dreturn:
1126   case Bytecodes::_areturn:
1127     assert(rsize() == -depth, "");
1128     inputs = -depth;
1129     break;
1130 
1131   case Bytecodes::_jsr:
1132   case Bytecodes::_jsr_w:
1133     inputs = 0;
1134     depth  = 1;                  // S.B. depth=1, not zero
1135     break;
1136 
1137   default:
1138     // bytecode produces a typed result
1139     inputs = rsize() - depth;
1140     assert(inputs >= 0, "");
1141     break;
1142   }
1143 
1144 #ifdef ASSERT
1145   // spot check
1146   int outputs = depth + inputs;
1147   assert(outputs >= 0, "sanity");
1148   switch (code) {
1149   case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1150   case Bytecodes::_athrow:    assert(inputs == 1 && outputs == 0, ""); break;
1151   case Bytecodes::_aload_0:   assert(inputs == 0 && outputs == 1, ""); break;
1152   case Bytecodes::_return:    assert(inputs == 0 && outputs == 0, ""); break;
1153   case Bytecodes::_drem:      assert(inputs == 4 && outputs == 2, ""); break;
1154   default:                    break;
1155   }
1156 #endif //ASSERT
1157 
1158   return true;
1159 }
1160 
1161 
1162 
1163 //------------------------------basic_plus_adr---------------------------------
1164 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1165   // short-circuit a common case
1166   if (offset == intcon(0))  return ptr;
1167   return _gvn.transform( new AddPNode(base, ptr, offset) );
1168 }
1169 
1170 Node* GraphKit::ConvI2L(Node* offset) {
1171   // short-circuit a common case
1172   jint offset_con = find_int_con(offset, Type::OffsetBot);
1173   if (offset_con != Type::OffsetBot) {
1174     return longcon((jlong) offset_con);
1175   }
1176   return _gvn.transform( new ConvI2LNode(offset));
1177 }
1178 
1179 Node* GraphKit::ConvI2UL(Node* offset) {
1180   juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1181   if (offset_con != (juint) Type::OffsetBot) {
1182     return longcon((julong) offset_con);
1183   }
1184   Node* conv = _gvn.transform( new ConvI2LNode(offset));
1185   Node* mask = _gvn.transform(ConLNode::make((julong) max_juint));
1186   return _gvn.transform( new AndLNode(conv, mask) );
1187 }
1188 
1189 Node* GraphKit::ConvL2I(Node* offset) {
1190   // short-circuit a common case
1191   jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1192   if (offset_con != (jlong)Type::OffsetBot) {
1193     return intcon((int) offset_con);
1194   }
1195   return _gvn.transform( new ConvL2INode(offset));
1196 }
1197 
1198 //-------------------------load_object_klass-----------------------------------
1199 Node* GraphKit::load_object_klass(Node* obj) {
1200   // Special-case a fresh allocation to avoid building nodes:
1201   Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1202   if (akls != nullptr)  return akls;
1203   Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1204   return _gvn.transform(LoadKlassNode::make(_gvn, nullptr, immutable_memory(), k_adr, TypeInstPtr::KLASS));
1205 }
1206 
1207 //-------------------------load_array_length-----------------------------------
1208 Node* GraphKit::load_array_length(Node* array) {
1209   // Special-case a fresh allocation to avoid building nodes:
1210   AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array);
1211   Node *alen;
1212   if (alloc == nullptr) {
1213     Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1214     alen = _gvn.transform( new LoadRangeNode(nullptr, immutable_memory(), r_adr, TypeInt::POS));
1215   } else {
1216     alen = array_ideal_length(alloc, _gvn.type(array)->is_oopptr(), false);
1217   }
1218   return alen;
1219 }
1220 
1221 Node* GraphKit::array_ideal_length(AllocateArrayNode* alloc,
1222                                    const TypeOopPtr* oop_type,
1223                                    bool replace_length_in_map) {
1224   Node* length = alloc->Ideal_length();
1225   if (replace_length_in_map == false || map()->find_edge(length) >= 0) {
1226     Node* ccast = alloc->make_ideal_length(oop_type, &_gvn);
1227     if (ccast != length) {
1228       // do not transform ccast here, it might convert to top node for
1229       // negative array length and break assumptions in parsing stage.
1230       _gvn.set_type_bottom(ccast);
1231       record_for_igvn(ccast);
1232       if (replace_length_in_map) {
1233         replace_in_map(length, ccast);
1234       }
1235       return ccast;
1236     }
1237   }
1238   return length;
1239 }
1240 
1241 //------------------------------do_null_check----------------------------------
1242 // Helper function to do a null pointer check.  Returned value is
1243 // the incoming address with null casted away.  You are allowed to use the
1244 // not-null value only if you are control dependent on the test.
1245 #ifndef PRODUCT
1246 extern uint explicit_null_checks_inserted,
1247             explicit_null_checks_elided;
1248 #endif
1249 Node* GraphKit::null_check_common(Node* value, BasicType type,
1250                                   // optional arguments for variations:
1251                                   bool assert_null,
1252                                   Node* *null_control,
1253                                   bool speculative) {
1254   assert(!assert_null || null_control == nullptr, "not both at once");
1255   if (stopped())  return top();
1256   NOT_PRODUCT(explicit_null_checks_inserted++);
1257 
1258   // Construct null check
1259   Node *chk = nullptr;
1260   switch(type) {
1261     case T_LONG   : chk = new CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1262     case T_INT    : chk = new CmpINode(value, _gvn.intcon(0)); break;
1263     case T_ARRAY  : // fall through
1264       type = T_OBJECT;  // simplify further tests
1265     case T_OBJECT : {
1266       const Type *t = _gvn.type( value );
1267 
1268       const TypeOopPtr* tp = t->isa_oopptr();
1269       if (tp != nullptr && !tp->is_loaded()
1270           // Only for do_null_check, not any of its siblings:
1271           && !assert_null && null_control == nullptr) {
1272         // Usually, any field access or invocation on an unloaded oop type
1273         // will simply fail to link, since the statically linked class is
1274         // likely also to be unloaded.  However, in -Xcomp mode, sometimes
1275         // the static class is loaded but the sharper oop type is not.
1276         // Rather than checking for this obscure case in lots of places,
1277         // we simply observe that a null check on an unloaded class
1278         // will always be followed by a nonsense operation, so we
1279         // can just issue the uncommon trap here.
1280         // Our access to the unloaded class will only be correct
1281         // after it has been loaded and initialized, which requires
1282         // a trip through the interpreter.
1283         ciKlass* klass = tp->unloaded_klass();
1284 #ifndef PRODUCT
1285         if (WizardMode) { tty->print("Null check of unloaded "); klass->print(); tty->cr(); }
1286 #endif
1287         uncommon_trap(Deoptimization::Reason_unloaded,
1288                       Deoptimization::Action_reinterpret,
1289                       klass, "!loaded");
1290         return top();
1291       }
1292 
1293       if (assert_null) {
1294         // See if the type is contained in NULL_PTR.
1295         // If so, then the value is already null.
1296         if (t->higher_equal(TypePtr::NULL_PTR)) {
1297           NOT_PRODUCT(explicit_null_checks_elided++);
1298           return value;           // Elided null assert quickly!
1299         }
1300       } else {
1301         // See if mixing in the null pointer changes type.
1302         // If so, then the null pointer was not allowed in the original
1303         // type.  In other words, "value" was not-null.
1304         if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1305           // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1306           NOT_PRODUCT(explicit_null_checks_elided++);
1307           return value;           // Elided null check quickly!
1308         }
1309       }
1310       chk = new CmpPNode( value, null() );
1311       break;
1312     }
1313 
1314     default:
1315       fatal("unexpected type: %s", type2name(type));
1316   }
1317   assert(chk != nullptr, "sanity check");
1318   chk = _gvn.transform(chk);
1319 
1320   BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1321   BoolNode *btst = new BoolNode( chk, btest);
1322   Node   *tst = _gvn.transform( btst );
1323 
1324   //-----------
1325   // if peephole optimizations occurred, a prior test existed.
1326   // If a prior test existed, maybe it dominates as we can avoid this test.
1327   if (tst != btst && type == T_OBJECT) {
1328     // At this point we want to scan up the CFG to see if we can
1329     // find an identical test (and so avoid this test altogether).
1330     Node *cfg = control();
1331     int depth = 0;
1332     while( depth < 16 ) {       // Limit search depth for speed
1333       if( cfg->Opcode() == Op_IfTrue &&
1334           cfg->in(0)->in(1) == tst ) {
1335         // Found prior test.  Use "cast_not_null" to construct an identical
1336         // CastPP (and hence hash to) as already exists for the prior test.
1337         // Return that casted value.
1338         if (assert_null) {
1339           replace_in_map(value, null());
1340           return null();  // do not issue the redundant test
1341         }
1342         Node *oldcontrol = control();
1343         set_control(cfg);
1344         Node *res = cast_not_null(value);
1345         set_control(oldcontrol);
1346         NOT_PRODUCT(explicit_null_checks_elided++);
1347         return res;
1348       }
1349       cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1350       if (cfg == nullptr)  break;  // Quit at region nodes
1351       depth++;
1352     }
1353   }
1354 
1355   //-----------
1356   // Branch to failure if null
1357   float ok_prob = PROB_MAX;  // a priori estimate:  nulls never happen
1358   Deoptimization::DeoptReason reason;
1359   if (assert_null) {
1360     reason = Deoptimization::reason_null_assert(speculative);
1361   } else if (type == T_OBJECT) {
1362     reason = Deoptimization::reason_null_check(speculative);
1363   } else {
1364     reason = Deoptimization::Reason_div0_check;
1365   }
1366   // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1367   // ciMethodData::has_trap_at will return a conservative -1 if any
1368   // must-be-null assertion has failed.  This could cause performance
1369   // problems for a method after its first do_null_assert failure.
1370   // Consider using 'Reason_class_check' instead?
1371 
1372   // To cause an implicit null check, we set the not-null probability
1373   // to the maximum (PROB_MAX).  For an explicit check the probability
1374   // is set to a smaller value.
1375   if (null_control != nullptr || too_many_traps(reason)) {
1376     // probability is less likely
1377     ok_prob =  PROB_LIKELY_MAG(3);
1378   } else if (!assert_null &&
1379              (ImplicitNullCheckThreshold > 0) &&
1380              method() != nullptr &&
1381              (method()->method_data()->trap_count(reason)
1382               >= (uint)ImplicitNullCheckThreshold)) {
1383     ok_prob =  PROB_LIKELY_MAG(3);
1384   }
1385 
1386   if (null_control != nullptr) {
1387     IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1388     Node* null_true = _gvn.transform( new IfFalseNode(iff));
1389     set_control(      _gvn.transform( new IfTrueNode(iff)));
1390 #ifndef PRODUCT
1391     if (null_true == top()) {
1392       explicit_null_checks_elided++;
1393     }
1394 #endif
1395     (*null_control) = null_true;
1396   } else {
1397     BuildCutout unless(this, tst, ok_prob);
1398     // Check for optimizer eliding test at parse time
1399     if (stopped()) {
1400       // Failure not possible; do not bother making uncommon trap.
1401       NOT_PRODUCT(explicit_null_checks_elided++);
1402     } else if (assert_null) {
1403       uncommon_trap(reason,
1404                     Deoptimization::Action_make_not_entrant,
1405                     nullptr, "assert_null");
1406     } else {
1407       replace_in_map(value, zerocon(type));
1408       builtin_throw(reason);
1409     }
1410   }
1411 
1412   // Must throw exception, fall-thru not possible?
1413   if (stopped()) {
1414     return top();               // No result
1415   }
1416 
1417   if (assert_null) {
1418     // Cast obj to null on this path.
1419     replace_in_map(value, zerocon(type));
1420     return zerocon(type);
1421   }
1422 
1423   // Cast obj to not-null on this path, if there is no null_control.
1424   // (If there is a null_control, a non-null value may come back to haunt us.)
1425   if (type == T_OBJECT) {
1426     Node* cast = cast_not_null(value, false);
1427     if (null_control == nullptr || (*null_control) == top())
1428       replace_in_map(value, cast);
1429     value = cast;
1430   }
1431 
1432   return value;
1433 }
1434 
1435 
1436 //------------------------------cast_not_null----------------------------------
1437 // Cast obj to not-null on this path
1438 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1439   const Type *t = _gvn.type(obj);
1440   const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1441   // Object is already not-null?
1442   if( t == t_not_null ) return obj;
1443 
1444   Node* cast = new CastPPNode(control(), obj,t_not_null);
1445   cast = _gvn.transform( cast );
1446 
1447   // Scan for instances of 'obj' in the current JVM mapping.
1448   // These instances are known to be not-null after the test.
1449   if (do_replace_in_map)
1450     replace_in_map(obj, cast);
1451 
1452   return cast;                  // Return casted value
1453 }
1454 
1455 // Sometimes in intrinsics, we implicitly know an object is not null
1456 // (there's no actual null check) so we can cast it to not null. In
1457 // the course of optimizations, the input to the cast can become null.
1458 // In that case that data path will die and we need the control path
1459 // to become dead as well to keep the graph consistent. So we have to
1460 // add a check for null for which one branch can't be taken. It uses
1461 // an Opaque4 node that will cause the check to be removed after loop
1462 // opts so the test goes away and the compiled code doesn't execute a
1463 // useless check.
1464 Node* GraphKit::must_be_not_null(Node* value, bool do_replace_in_map) {
1465   if (!TypePtr::NULL_PTR->higher_equal(_gvn.type(value))) {
1466     return value;
1467   }
1468   Node* chk = _gvn.transform(new CmpPNode(value, null()));
1469   Node *tst = _gvn.transform(new BoolNode(chk, BoolTest::ne));
1470   Node* opaq = _gvn.transform(new Opaque4Node(C, tst, intcon(1)));
1471   IfNode *iff = new IfNode(control(), opaq, PROB_MAX, COUNT_UNKNOWN);
1472   _gvn.set_type(iff, iff->Value(&_gvn));
1473   if (!tst->is_Con()) {
1474     record_for_igvn(iff);
1475   }
1476   Node *if_f = _gvn.transform(new IfFalseNode(iff));
1477   Node *frame = _gvn.transform(new ParmNode(C->start(), TypeFunc::FramePtr));
1478   Node* halt = _gvn.transform(new HaltNode(if_f, frame, "unexpected null in intrinsic"));
1479   C->root()->add_req(halt);
1480   Node *if_t = _gvn.transform(new IfTrueNode(iff));
1481   set_control(if_t);
1482   return cast_not_null(value, do_replace_in_map);
1483 }
1484 
1485 
1486 //--------------------------replace_in_map-------------------------------------
1487 void GraphKit::replace_in_map(Node* old, Node* neww) {
1488   if (old == neww) {
1489     return;
1490   }
1491 
1492   map()->replace_edge(old, neww);
1493 
1494   // Note: This operation potentially replaces any edge
1495   // on the map.  This includes locals, stack, and monitors
1496   // of the current (innermost) JVM state.
1497 
1498   // don't let inconsistent types from profiling escape this
1499   // method
1500 
1501   const Type* told = _gvn.type(old);
1502   const Type* tnew = _gvn.type(neww);
1503 
1504   if (!tnew->higher_equal(told)) {
1505     return;
1506   }
1507 
1508   map()->record_replaced_node(old, neww);
1509 }
1510 
1511 
1512 //=============================================================================
1513 //--------------------------------memory---------------------------------------
1514 Node* GraphKit::memory(uint alias_idx) {
1515   MergeMemNode* mem = merged_memory();
1516   Node* p = mem->memory_at(alias_idx);
1517   assert(p != mem->empty_memory(), "empty");
1518   _gvn.set_type(p, Type::MEMORY);  // must be mapped
1519   return p;
1520 }
1521 
1522 //-----------------------------reset_memory------------------------------------
1523 Node* GraphKit::reset_memory() {
1524   Node* mem = map()->memory();
1525   // do not use this node for any more parsing!
1526   debug_only( map()->set_memory((Node*)nullptr) );
1527   return _gvn.transform( mem );
1528 }
1529 
1530 //------------------------------set_all_memory---------------------------------
1531 void GraphKit::set_all_memory(Node* newmem) {
1532   Node* mergemem = MergeMemNode::make(newmem);
1533   gvn().set_type_bottom(mergemem);
1534   map()->set_memory(mergemem);
1535 }
1536 
1537 //------------------------------set_all_memory_call----------------------------
1538 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1539   Node* newmem = _gvn.transform( new ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1540   set_all_memory(newmem);
1541 }
1542 
1543 //=============================================================================
1544 //
1545 // parser factory methods for MemNodes
1546 //
1547 // These are layered on top of the factory methods in LoadNode and StoreNode,
1548 // and integrate with the parser's memory state and _gvn engine.
1549 //
1550 
1551 // factory methods in "int adr_idx"
1552 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1553                           int adr_idx,
1554                           MemNode::MemOrd mo,
1555                           LoadNode::ControlDependency control_dependency,
1556                           bool require_atomic_access,
1557                           bool unaligned,
1558                           bool mismatched,
1559                           bool unsafe,
1560                           uint8_t barrier_data) {
1561   assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1562   const TypePtr* adr_type = nullptr; // debug-mode-only argument
1563   debug_only(adr_type = C->get_adr_type(adr_idx));
1564   Node* mem = memory(adr_idx);
1565   Node* ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, require_atomic_access, unaligned, mismatched, unsafe, barrier_data);
1566   ld = _gvn.transform(ld);
1567   if (((bt == T_OBJECT) && C->do_escape_analysis()) || C->eliminate_boxing()) {
1568     // Improve graph before escape analysis and boxing elimination.
1569     record_for_igvn(ld);
1570     if (ld->is_DecodeN()) {
1571       // Also record the actual load (LoadN) in case ld is DecodeN. In some
1572       // rare corner cases, ld->in(1) can be something other than LoadN (e.g.,
1573       // a Phi). Recording such cases is still perfectly sound, but may be
1574       // unnecessary and result in some minor IGVN overhead.
1575       record_for_igvn(ld->in(1));
1576     }
1577   }
1578   return ld;
1579 }
1580 
1581 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1582                                 int adr_idx,
1583                                 MemNode::MemOrd mo,
1584                                 bool require_atomic_access,
1585                                 bool unaligned,
1586                                 bool mismatched,
1587                                 bool unsafe,
1588                                 int barrier_data) {
1589   assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1590   const TypePtr* adr_type = nullptr;
1591   debug_only(adr_type = C->get_adr_type(adr_idx));
1592   Node *mem = memory(adr_idx);
1593   Node* st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo, require_atomic_access);
1594   if (unaligned) {
1595     st->as_Store()->set_unaligned_access();
1596   }
1597   if (mismatched) {
1598     st->as_Store()->set_mismatched_access();
1599   }
1600   if (unsafe) {
1601     st->as_Store()->set_unsafe_access();
1602   }
1603   st->as_Store()->set_barrier_data(barrier_data);
1604   st = _gvn.transform(st);
1605   set_memory(st, adr_idx);
1606   // Back-to-back stores can only remove intermediate store with DU info
1607   // so push on worklist for optimizer.
1608   if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1609     record_for_igvn(st);
1610 
1611   return st;
1612 }
1613 
1614 Node* GraphKit::access_store_at(Node* obj,
1615                                 Node* adr,
1616                                 const TypePtr* adr_type,
1617                                 Node* val,
1618                                 const Type* val_type,
1619                                 BasicType bt,
1620                                 DecoratorSet decorators) {
1621   // Transformation of a value which could be null pointer (CastPP #null)
1622   // could be delayed during Parse (for example, in adjust_map_after_if()).
1623   // Execute transformation here to avoid barrier generation in such case.
1624   if (_gvn.type(val) == TypePtr::NULL_PTR) {
1625     val = _gvn.makecon(TypePtr::NULL_PTR);
1626   }
1627 
1628   if (stopped()) {
1629     return top(); // Dead path ?
1630   }
1631 
1632   assert(val != nullptr, "not dead path");
1633 
1634   C2AccessValuePtr addr(adr, adr_type);
1635   C2AccessValue value(val, val_type);
1636   C2ParseAccess access(this, decorators | C2_WRITE_ACCESS, bt, obj, addr);
1637   if (access.is_raw()) {
1638     return _barrier_set->BarrierSetC2::store_at(access, value);
1639   } else {
1640     return _barrier_set->store_at(access, value);
1641   }
1642 }
1643 
1644 Node* GraphKit::access_load_at(Node* obj,   // containing obj
1645                                Node* adr,   // actual address to store val at
1646                                const TypePtr* adr_type,
1647                                const Type* val_type,
1648                                BasicType bt,
1649                                DecoratorSet decorators) {
1650   if (stopped()) {
1651     return top(); // Dead path ?
1652   }
1653 
1654   C2AccessValuePtr addr(adr, adr_type);
1655   C2ParseAccess access(this, decorators | C2_READ_ACCESS, bt, obj, addr);
1656   if (access.is_raw()) {
1657     return _barrier_set->BarrierSetC2::load_at(access, val_type);
1658   } else {
1659     return _barrier_set->load_at(access, val_type);
1660   }
1661 }
1662 
1663 Node* GraphKit::access_load(Node* adr,   // actual address to load val at
1664                             const Type* val_type,
1665                             BasicType bt,
1666                             DecoratorSet decorators) {
1667   if (stopped()) {
1668     return top(); // Dead path ?
1669   }
1670 
1671   C2AccessValuePtr addr(adr, adr->bottom_type()->is_ptr());
1672   C2ParseAccess access(this, decorators | C2_READ_ACCESS, bt, nullptr, addr);
1673   if (access.is_raw()) {
1674     return _barrier_set->BarrierSetC2::load_at(access, val_type);
1675   } else {
1676     return _barrier_set->load_at(access, val_type);
1677   }
1678 }
1679 
1680 Node* GraphKit::access_atomic_cmpxchg_val_at(Node* obj,
1681                                              Node* adr,
1682                                              const TypePtr* adr_type,
1683                                              int alias_idx,
1684                                              Node* expected_val,
1685                                              Node* new_val,
1686                                              const Type* value_type,
1687                                              BasicType bt,
1688                                              DecoratorSet decorators) {
1689   C2AccessValuePtr addr(adr, adr_type);
1690   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1691                         bt, obj, addr, alias_idx);
1692   if (access.is_raw()) {
1693     return _barrier_set->BarrierSetC2::atomic_cmpxchg_val_at(access, expected_val, new_val, value_type);
1694   } else {
1695     return _barrier_set->atomic_cmpxchg_val_at(access, expected_val, new_val, value_type);
1696   }
1697 }
1698 
1699 Node* GraphKit::access_atomic_cmpxchg_bool_at(Node* obj,
1700                                               Node* adr,
1701                                               const TypePtr* adr_type,
1702                                               int alias_idx,
1703                                               Node* expected_val,
1704                                               Node* new_val,
1705                                               const Type* value_type,
1706                                               BasicType bt,
1707                                               DecoratorSet decorators) {
1708   C2AccessValuePtr addr(adr, adr_type);
1709   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1710                         bt, obj, addr, alias_idx);
1711   if (access.is_raw()) {
1712     return _barrier_set->BarrierSetC2::atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type);
1713   } else {
1714     return _barrier_set->atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type);
1715   }
1716 }
1717 
1718 Node* GraphKit::access_atomic_xchg_at(Node* obj,
1719                                       Node* adr,
1720                                       const TypePtr* adr_type,
1721                                       int alias_idx,
1722                                       Node* new_val,
1723                                       const Type* value_type,
1724                                       BasicType bt,
1725                                       DecoratorSet decorators) {
1726   C2AccessValuePtr addr(adr, adr_type);
1727   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1728                         bt, obj, addr, alias_idx);
1729   if (access.is_raw()) {
1730     return _barrier_set->BarrierSetC2::atomic_xchg_at(access, new_val, value_type);
1731   } else {
1732     return _barrier_set->atomic_xchg_at(access, new_val, value_type);
1733   }
1734 }
1735 
1736 Node* GraphKit::access_atomic_add_at(Node* obj,
1737                                      Node* adr,
1738                                      const TypePtr* adr_type,
1739                                      int alias_idx,
1740                                      Node* new_val,
1741                                      const Type* value_type,
1742                                      BasicType bt,
1743                                      DecoratorSet decorators) {
1744   C2AccessValuePtr addr(adr, adr_type);
1745   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS, bt, obj, addr, alias_idx);
1746   if (access.is_raw()) {
1747     return _barrier_set->BarrierSetC2::atomic_add_at(access, new_val, value_type);
1748   } else {
1749     return _barrier_set->atomic_add_at(access, new_val, value_type);
1750   }
1751 }
1752 
1753 void GraphKit::access_clone(Node* src, Node* dst, Node* size, bool is_array) {
1754   return _barrier_set->clone(this, src, dst, size, is_array);
1755 }
1756 
1757 //-------------------------array_element_address-------------------------
1758 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1759                                       const TypeInt* sizetype, Node* ctrl) {
1760   uint shift  = exact_log2(type2aelembytes(elembt));
1761   uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1762 
1763   // short-circuit a common case (saves lots of confusing waste motion)
1764   jint idx_con = find_int_con(idx, -1);
1765   if (idx_con >= 0) {
1766     intptr_t offset = header + ((intptr_t)idx_con << shift);
1767     return basic_plus_adr(ary, offset);
1768   }
1769 
1770   // must be correct type for alignment purposes
1771   Node* base  = basic_plus_adr(ary, header);
1772   idx = Compile::conv_I2X_index(&_gvn, idx, sizetype, ctrl);
1773   Node* scale = _gvn.transform( new LShiftXNode(idx, intcon(shift)) );
1774   return basic_plus_adr(ary, base, scale);
1775 }
1776 
1777 //-------------------------load_array_element-------------------------
1778 Node* GraphKit::load_array_element(Node* ary, Node* idx, const TypeAryPtr* arytype, bool set_ctrl) {
1779   const Type* elemtype = arytype->elem();
1780   BasicType elembt = elemtype->array_element_basic_type();
1781   Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1782   if (elembt == T_NARROWOOP) {
1783     elembt = T_OBJECT; // To satisfy switch in LoadNode::make()
1784   }
1785   Node* ld = access_load_at(ary, adr, arytype, elemtype, elembt,
1786                             IN_HEAP | IS_ARRAY | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0));
1787   return ld;
1788 }
1789 
1790 //-------------------------set_arguments_for_java_call-------------------------
1791 // Arguments (pre-popped from the stack) are taken from the JVMS.
1792 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1793   // Add the call arguments:
1794   uint nargs = call->method()->arg_size();
1795   for (uint i = 0; i < nargs; i++) {
1796     Node* arg = argument(i);
1797     call->init_req(i + TypeFunc::Parms, arg);
1798   }
1799 }
1800 
1801 //---------------------------set_edges_for_java_call---------------------------
1802 // Connect a newly created call into the current JVMS.
1803 // A return value node (if any) is returned from set_edges_for_java_call.
1804 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1805 
1806   // Add the predefined inputs:
1807   call->init_req( TypeFunc::Control, control() );
1808   call->init_req( TypeFunc::I_O    , i_o() );
1809   call->init_req( TypeFunc::Memory , reset_memory() );
1810   call->init_req( TypeFunc::FramePtr, frameptr() );
1811   call->init_req( TypeFunc::ReturnAdr, top() );
1812 
1813   add_safepoint_edges(call, must_throw);
1814 
1815   Node* xcall = _gvn.transform(call);
1816 
1817   if (xcall == top()) {
1818     set_control(top());
1819     return;
1820   }
1821   assert(xcall == call, "call identity is stable");
1822 
1823   // Re-use the current map to produce the result.
1824 
1825   set_control(_gvn.transform(new ProjNode(call, TypeFunc::Control)));
1826   set_i_o(    _gvn.transform(new ProjNode(call, TypeFunc::I_O    , separate_io_proj)));
1827   set_all_memory_call(xcall, separate_io_proj);
1828 
1829   //return xcall;   // no need, caller already has it
1830 }
1831 
1832 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj, bool deoptimize) {
1833   if (stopped())  return top();  // maybe the call folded up?
1834 
1835   // Capture the return value, if any.
1836   Node* ret;
1837   if (call->method() == nullptr ||
1838       call->method()->return_type()->basic_type() == T_VOID)
1839         ret = top();
1840   else  ret = _gvn.transform(new ProjNode(call, TypeFunc::Parms));
1841 
1842   // Note:  Since any out-of-line call can produce an exception,
1843   // we always insert an I_O projection from the call into the result.
1844 
1845   make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj, deoptimize);
1846 
1847   if (separate_io_proj) {
1848     // The caller requested separate projections be used by the fall
1849     // through and exceptional paths, so replace the projections for
1850     // the fall through path.
1851     set_i_o(_gvn.transform( new ProjNode(call, TypeFunc::I_O) ));
1852     set_all_memory(_gvn.transform( new ProjNode(call, TypeFunc::Memory) ));
1853   }
1854   return ret;
1855 }
1856 
1857 //--------------------set_predefined_input_for_runtime_call--------------------
1858 // Reading and setting the memory state is way conservative here.
1859 // The real problem is that I am not doing real Type analysis on memory,
1860 // so I cannot distinguish card mark stores from other stores.  Across a GC
1861 // point the Store Barrier and the card mark memory has to agree.  I cannot
1862 // have a card mark store and its barrier split across the GC point from
1863 // either above or below.  Here I get that to happen by reading ALL of memory.
1864 // A better answer would be to separate out card marks from other memory.
1865 // For now, return the input memory state, so that it can be reused
1866 // after the call, if this call has restricted memory effects.
1867 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call, Node* narrow_mem) {
1868   // Set fixed predefined input arguments
1869   Node* memory = reset_memory();
1870   Node* m = narrow_mem == nullptr ? memory : narrow_mem;
1871   call->init_req( TypeFunc::Control,   control()  );
1872   call->init_req( TypeFunc::I_O,       top()      ); // does no i/o
1873   call->init_req( TypeFunc::Memory,    m          ); // may gc ptrs
1874   call->init_req( TypeFunc::FramePtr,  frameptr() );
1875   call->init_req( TypeFunc::ReturnAdr, top()      );
1876   return memory;
1877 }
1878 
1879 //-------------------set_predefined_output_for_runtime_call--------------------
1880 // Set control and memory (not i_o) from the call.
1881 // If keep_mem is not null, use it for the output state,
1882 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1883 // If hook_mem is null, this call produces no memory effects at all.
1884 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1885 // then only that memory slice is taken from the call.
1886 // In the last case, we must put an appropriate memory barrier before
1887 // the call, so as to create the correct anti-dependencies on loads
1888 // preceding the call.
1889 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1890                                                       Node* keep_mem,
1891                                                       const TypePtr* hook_mem) {
1892   // no i/o
1893   set_control(_gvn.transform( new ProjNode(call,TypeFunc::Control) ));
1894   if (keep_mem) {
1895     // First clone the existing memory state
1896     set_all_memory(keep_mem);
1897     if (hook_mem != nullptr) {
1898       // Make memory for the call
1899       Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
1900       // Set the RawPtr memory state only.  This covers all the heap top/GC stuff
1901       // We also use hook_mem to extract specific effects from arraycopy stubs.
1902       set_memory(mem, hook_mem);
1903     }
1904     // ...else the call has NO memory effects.
1905 
1906     // Make sure the call advertises its memory effects precisely.
1907     // This lets us build accurate anti-dependences in gcm.cpp.
1908     assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1909            "call node must be constructed correctly");
1910   } else {
1911     assert(hook_mem == nullptr, "");
1912     // This is not a "slow path" call; all memory comes from the call.
1913     set_all_memory_call(call);
1914   }
1915 }
1916 
1917 // Keep track of MergeMems feeding into other MergeMems
1918 static void add_mergemem_users_to_worklist(Unique_Node_List& wl, Node* mem) {
1919   if (!mem->is_MergeMem()) {
1920     return;
1921   }
1922   for (SimpleDUIterator i(mem); i.has_next(); i.next()) {
1923     Node* use = i.get();
1924     if (use->is_MergeMem()) {
1925       wl.push(use);
1926     }
1927   }
1928 }
1929 
1930 // Replace the call with the current state of the kit.
1931 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes) {
1932   JVMState* ejvms = nullptr;
1933   if (has_exceptions()) {
1934     ejvms = transfer_exceptions_into_jvms();
1935   }
1936 
1937   ReplacedNodes replaced_nodes = map()->replaced_nodes();
1938   ReplacedNodes replaced_nodes_exception;
1939   Node* ex_ctl = top();
1940 
1941   SafePointNode* final_state = stop();
1942 
1943   // Find all the needed outputs of this call
1944   CallProjections callprojs;
1945   call->extract_projections(&callprojs, true);
1946 
1947   Unique_Node_List wl;
1948   Node* init_mem = call->in(TypeFunc::Memory);
1949   Node* final_mem = final_state->in(TypeFunc::Memory);
1950   Node* final_ctl = final_state->in(TypeFunc::Control);
1951   Node* final_io = final_state->in(TypeFunc::I_O);
1952 
1953   // Replace all the old call edges with the edges from the inlining result
1954   if (callprojs.fallthrough_catchproj != nullptr) {
1955     C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
1956   }
1957   if (callprojs.fallthrough_memproj != nullptr) {
1958     if (final_mem->is_MergeMem()) {
1959       // Parser's exits MergeMem was not transformed but may be optimized
1960       final_mem = _gvn.transform(final_mem);
1961     }
1962     C->gvn_replace_by(callprojs.fallthrough_memproj,   final_mem);
1963     add_mergemem_users_to_worklist(wl, final_mem);
1964   }
1965   if (callprojs.fallthrough_ioproj != nullptr) {
1966     C->gvn_replace_by(callprojs.fallthrough_ioproj,    final_io);
1967   }
1968 
1969   // Replace the result with the new result if it exists and is used
1970   if (callprojs.resproj != nullptr && result != nullptr) {
1971     C->gvn_replace_by(callprojs.resproj, result);
1972   }
1973 
1974   if (ejvms == nullptr) {
1975     // No exception edges to simply kill off those paths
1976     if (callprojs.catchall_catchproj != nullptr) {
1977       C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1978     }
1979     if (callprojs.catchall_memproj != nullptr) {
1980       C->gvn_replace_by(callprojs.catchall_memproj,   C->top());
1981     }
1982     if (callprojs.catchall_ioproj != nullptr) {
1983       C->gvn_replace_by(callprojs.catchall_ioproj,    C->top());
1984     }
1985     // Replace the old exception object with top
1986     if (callprojs.exobj != nullptr) {
1987       C->gvn_replace_by(callprojs.exobj, C->top());
1988     }
1989   } else {
1990     GraphKit ekit(ejvms);
1991 
1992     // Load my combined exception state into the kit, with all phis transformed:
1993     SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1994     replaced_nodes_exception = ex_map->replaced_nodes();
1995 
1996     Node* ex_oop = ekit.use_exception_state(ex_map);
1997 
1998     if (callprojs.catchall_catchproj != nullptr) {
1999       C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
2000       ex_ctl = ekit.control();
2001     }
2002     if (callprojs.catchall_memproj != nullptr) {
2003       Node* ex_mem = ekit.reset_memory();
2004       C->gvn_replace_by(callprojs.catchall_memproj,   ex_mem);
2005       add_mergemem_users_to_worklist(wl, ex_mem);
2006     }
2007     if (callprojs.catchall_ioproj != nullptr) {
2008       C->gvn_replace_by(callprojs.catchall_ioproj,    ekit.i_o());
2009     }
2010 
2011     // Replace the old exception object with the newly created one
2012     if (callprojs.exobj != nullptr) {
2013       C->gvn_replace_by(callprojs.exobj, ex_oop);
2014     }
2015   }
2016 
2017   // Disconnect the call from the graph
2018   call->disconnect_inputs(C);
2019   C->gvn_replace_by(call, C->top());
2020 
2021   // Clean up any MergeMems that feed other MergeMems since the
2022   // optimizer doesn't like that.
2023   while (wl.size() > 0) {
2024     _gvn.transform(wl.pop());
2025   }
2026 
2027   if (callprojs.fallthrough_catchproj != nullptr && !final_ctl->is_top() && do_replaced_nodes) {
2028     replaced_nodes.apply(C, final_ctl);
2029   }
2030   if (!ex_ctl->is_top() && do_replaced_nodes) {
2031     replaced_nodes_exception.apply(C, ex_ctl);
2032   }
2033 }
2034 
2035 
2036 //------------------------------increment_counter------------------------------
2037 // for statistics: increment a VM counter by 1
2038 
2039 void GraphKit::increment_counter(address counter_addr) {
2040   Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
2041   increment_counter(adr1);
2042 }
2043 
2044 void GraphKit::increment_counter(Node* counter_addr) {
2045   int adr_type = Compile::AliasIdxRaw;
2046   Node* ctrl = control();
2047   Node* cnt  = make_load(ctrl, counter_addr, TypeLong::LONG, T_LONG, adr_type, MemNode::unordered);
2048   Node* incr = _gvn.transform(new AddLNode(cnt, _gvn.longcon(1)));
2049   store_to_memory(ctrl, counter_addr, incr, T_LONG, adr_type, MemNode::unordered);
2050 }
2051 
2052 
2053 //------------------------------uncommon_trap----------------------------------
2054 // Bail out to the interpreter in mid-method.  Implemented by calling the
2055 // uncommon_trap blob.  This helper function inserts a runtime call with the
2056 // right debug info.
2057 Node* GraphKit::uncommon_trap(int trap_request,
2058                              ciKlass* klass, const char* comment,
2059                              bool must_throw,
2060                              bool keep_exact_action) {
2061   if (failing_internal()) {
2062     stop();
2063   }
2064   if (stopped())  return nullptr; // trap reachable?
2065 
2066   // Note:  If ProfileTraps is true, and if a deopt. actually
2067   // occurs here, the runtime will make sure an MDO exists.  There is
2068   // no need to call method()->ensure_method_data() at this point.
2069 
2070   // Set the stack pointer to the right value for reexecution:
2071   set_sp(reexecute_sp());
2072 
2073 #ifdef ASSERT
2074   if (!must_throw) {
2075     // Make sure the stack has at least enough depth to execute
2076     // the current bytecode.
2077     int inputs, ignored_depth;
2078     if (compute_stack_effects(inputs, ignored_depth)) {
2079       assert(sp() >= inputs, "must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
2080              Bytecodes::name(java_bc()), sp(), inputs);
2081     }
2082   }
2083 #endif
2084 
2085   Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
2086   Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
2087 
2088   switch (action) {
2089   case Deoptimization::Action_maybe_recompile:
2090   case Deoptimization::Action_reinterpret:
2091     // Temporary fix for 6529811 to allow virtual calls to be sure they
2092     // get the chance to go from mono->bi->mega
2093     if (!keep_exact_action &&
2094         Deoptimization::trap_request_index(trap_request) < 0 &&
2095         too_many_recompiles(reason)) {
2096       // This BCI is causing too many recompilations.
2097       if (C->log() != nullptr) {
2098         C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'",
2099                 Deoptimization::trap_reason_name(reason),
2100                 Deoptimization::trap_action_name(action));
2101       }
2102       action = Deoptimization::Action_none;
2103       trap_request = Deoptimization::make_trap_request(reason, action);
2104     } else {
2105       C->set_trap_can_recompile(true);
2106     }
2107     break;
2108   case Deoptimization::Action_make_not_entrant:
2109     C->set_trap_can_recompile(true);
2110     break;
2111   case Deoptimization::Action_none:
2112   case Deoptimization::Action_make_not_compilable:
2113     break;
2114   default:
2115 #ifdef ASSERT
2116     fatal("unknown action %d: %s", action, Deoptimization::trap_action_name(action));
2117 #endif
2118     break;
2119   }
2120 
2121   if (TraceOptoParse) {
2122     char buf[100];
2123     tty->print_cr("Uncommon trap %s at bci:%d",
2124                   Deoptimization::format_trap_request(buf, sizeof(buf),
2125                                                       trap_request), bci());
2126   }
2127 
2128   CompileLog* log = C->log();
2129   if (log != nullptr) {
2130     int kid = (klass == nullptr)? -1: log->identify(klass);
2131     log->begin_elem("uncommon_trap bci='%d'", bci());
2132     char buf[100];
2133     log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2134                                                           trap_request));
2135     if (kid >= 0)         log->print(" klass='%d'", kid);
2136     if (comment != nullptr)  log->print(" comment='%s'", comment);
2137     log->end_elem();
2138   }
2139 
2140   // Make sure any guarding test views this path as very unlikely
2141   Node *i0 = control()->in(0);
2142   if (i0 != nullptr && i0->is_If()) {        // Found a guarding if test?
2143     IfNode *iff = i0->as_If();
2144     float f = iff->_prob;   // Get prob
2145     if (control()->Opcode() == Op_IfTrue) {
2146       if (f > PROB_UNLIKELY_MAG(4))
2147         iff->_prob = PROB_MIN;
2148     } else {
2149       if (f < PROB_LIKELY_MAG(4))
2150         iff->_prob = PROB_MAX;
2151     }
2152   }
2153 
2154   // Clear out dead values from the debug info.
2155   kill_dead_locals();
2156 
2157   // Now insert the uncommon trap subroutine call
2158   address call_addr = OptoRuntime::uncommon_trap_blob()->entry_point();
2159   const TypePtr* no_memory_effects = nullptr;
2160   // Pass the index of the class to be loaded
2161   Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2162                                  (must_throw ? RC_MUST_THROW : 0),
2163                                  OptoRuntime::uncommon_trap_Type(),
2164                                  call_addr, "uncommon_trap", no_memory_effects,
2165                                  intcon(trap_request));
2166   assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2167          "must extract request correctly from the graph");
2168   assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2169 
2170   call->set_req(TypeFunc::ReturnAdr, returnadr());
2171   // The debug info is the only real input to this call.
2172 
2173   // Halt-and-catch fire here.  The above call should never return!
2174   HaltNode* halt = new HaltNode(control(), frameptr(), "uncommon trap returned which should never happen"
2175                                                        PRODUCT_ONLY(COMMA /*reachable*/false));
2176   _gvn.set_type_bottom(halt);
2177   root()->add_req(halt);
2178 
2179   stop_and_kill_map();
2180   return call;
2181 }
2182 
2183 
2184 //--------------------------just_allocated_object------------------------------
2185 // Report the object that was just allocated.
2186 // It must be the case that there are no intervening safepoints.
2187 // We use this to determine if an object is so "fresh" that
2188 // it does not require card marks.
2189 Node* GraphKit::just_allocated_object(Node* current_control) {
2190   Node* ctrl = current_control;
2191   // Object::<init> is invoked after allocation, most of invoke nodes
2192   // will be reduced, but a region node is kept in parse time, we check
2193   // the pattern and skip the region node if it degraded to a copy.
2194   if (ctrl != nullptr && ctrl->is_Region() && ctrl->req() == 2 &&
2195       ctrl->as_Region()->is_copy()) {
2196     ctrl = ctrl->as_Region()->is_copy();
2197   }
2198   if (C->recent_alloc_ctl() == ctrl) {
2199    return C->recent_alloc_obj();
2200   }
2201   return nullptr;
2202 }
2203 
2204 
2205 /**
2206  * Record profiling data exact_kls for Node n with the type system so
2207  * that it can propagate it (speculation)
2208  *
2209  * @param n          node that the type applies to
2210  * @param exact_kls  type from profiling
2211  * @param maybe_null did profiling see null?
2212  *
2213  * @return           node with improved type
2214  */
2215 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind) {
2216   const Type* current_type = _gvn.type(n);
2217   assert(UseTypeSpeculation, "type speculation must be on");
2218 
2219   const TypePtr* speculative = current_type->speculative();
2220 
2221   // Should the klass from the profile be recorded in the speculative type?
2222   if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2223     const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls, Type::trust_interfaces);
2224     const TypeOopPtr* xtype = tklass->as_instance_type();
2225     assert(xtype->klass_is_exact(), "Should be exact");
2226     // Any reason to believe n is not null (from this profiling or a previous one)?
2227     assert(ptr_kind != ProfileAlwaysNull, "impossible here");
2228     const TypePtr* ptr = (ptr_kind == ProfileMaybeNull && current_type->speculative_maybe_null()) ? TypePtr::BOTTOM : TypePtr::NOTNULL;
2229     // record the new speculative type's depth
2230     speculative = xtype->cast_to_ptr_type(ptr->ptr())->is_ptr();
2231     speculative = speculative->with_inline_depth(jvms()->depth());
2232   } else if (current_type->would_improve_ptr(ptr_kind)) {
2233     // Profiling report that null was never seen so we can change the
2234     // speculative type to non null ptr.
2235     if (ptr_kind == ProfileAlwaysNull) {
2236       speculative = TypePtr::NULL_PTR;
2237     } else {
2238       assert(ptr_kind == ProfileNeverNull, "nothing else is an improvement");
2239       const TypePtr* ptr = TypePtr::NOTNULL;
2240       if (speculative != nullptr) {
2241         speculative = speculative->cast_to_ptr_type(ptr->ptr())->is_ptr();
2242       } else {
2243         speculative = ptr;
2244       }
2245     }
2246   }
2247 
2248   if (speculative != current_type->speculative()) {
2249     // Build a type with a speculative type (what we think we know
2250     // about the type but will need a guard when we use it)
2251     const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2252     // We're changing the type, we need a new CheckCast node to carry
2253     // the new type. The new type depends on the control: what
2254     // profiling tells us is only valid from here as far as we can
2255     // tell.
2256     Node* cast = new CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2257     cast = _gvn.transform(cast);
2258     replace_in_map(n, cast);
2259     n = cast;
2260   }
2261 
2262   return n;
2263 }
2264 
2265 /**
2266  * Record profiling data from receiver profiling at an invoke with the
2267  * type system so that it can propagate it (speculation)
2268  *
2269  * @param n  receiver node
2270  *
2271  * @return   node with improved type
2272  */
2273 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2274   if (!UseTypeSpeculation) {
2275     return n;
2276   }
2277   ciKlass* exact_kls = profile_has_unique_klass();
2278   ProfilePtrKind ptr_kind = ProfileMaybeNull;
2279   if ((java_bc() == Bytecodes::_checkcast ||
2280        java_bc() == Bytecodes::_instanceof ||
2281        java_bc() == Bytecodes::_aastore) &&
2282       method()->method_data()->is_mature()) {
2283     ciProfileData* data = method()->method_data()->bci_to_data(bci());
2284     if (data != nullptr) {
2285       if (!data->as_BitData()->null_seen()) {
2286         ptr_kind = ProfileNeverNull;
2287       } else {
2288         assert(data->is_ReceiverTypeData(), "bad profile data type");
2289         ciReceiverTypeData* call = (ciReceiverTypeData*)data->as_ReceiverTypeData();
2290         uint i = 0;
2291         for (; i < call->row_limit(); i++) {
2292           ciKlass* receiver = call->receiver(i);
2293           if (receiver != nullptr) {
2294             break;
2295           }
2296         }
2297         ptr_kind = (i == call->row_limit()) ? ProfileAlwaysNull : ProfileMaybeNull;
2298       }
2299     }
2300   }
2301   return record_profile_for_speculation(n, exact_kls, ptr_kind);
2302 }
2303 
2304 /**
2305  * Record profiling data from argument profiling at an invoke with the
2306  * type system so that it can propagate it (speculation)
2307  *
2308  * @param dest_method  target method for the call
2309  * @param bc           what invoke bytecode is this?
2310  */
2311 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2312   if (!UseTypeSpeculation) {
2313     return;
2314   }
2315   const TypeFunc* tf    = TypeFunc::make(dest_method);
2316   int             nargs = tf->domain()->cnt() - TypeFunc::Parms;
2317   int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2318   for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2319     const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2320     if (is_reference_type(targ->basic_type())) {
2321       ProfilePtrKind ptr_kind = ProfileMaybeNull;
2322       ciKlass* better_type = nullptr;
2323       if (method()->argument_profiled_type(bci(), i, better_type, ptr_kind)) {
2324         record_profile_for_speculation(argument(j), better_type, ptr_kind);
2325       }
2326       i++;
2327     }
2328   }
2329 }
2330 
2331 /**
2332  * Record profiling data from parameter profiling at an invoke with
2333  * the type system so that it can propagate it (speculation)
2334  */
2335 void GraphKit::record_profiled_parameters_for_speculation() {
2336   if (!UseTypeSpeculation) {
2337     return;
2338   }
2339   for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2340     if (_gvn.type(local(i))->isa_oopptr()) {
2341       ProfilePtrKind ptr_kind = ProfileMaybeNull;
2342       ciKlass* better_type = nullptr;
2343       if (method()->parameter_profiled_type(j, better_type, ptr_kind)) {
2344         record_profile_for_speculation(local(i), better_type, ptr_kind);
2345       }
2346       j++;
2347     }
2348   }
2349 }
2350 
2351 /**
2352  * Record profiling data from return value profiling at an invoke with
2353  * the type system so that it can propagate it (speculation)
2354  */
2355 void GraphKit::record_profiled_return_for_speculation() {
2356   if (!UseTypeSpeculation) {
2357     return;
2358   }
2359   ProfilePtrKind ptr_kind = ProfileMaybeNull;
2360   ciKlass* better_type = nullptr;
2361   if (method()->return_profiled_type(bci(), better_type, ptr_kind)) {
2362     // If profiling reports a single type for the return value,
2363     // feed it to the type system so it can propagate it as a
2364     // speculative type
2365     record_profile_for_speculation(stack(sp()-1), better_type, ptr_kind);
2366   }
2367 }
2368 
2369 void GraphKit::round_double_arguments(ciMethod* dest_method) {
2370   if (Matcher::strict_fp_requires_explicit_rounding) {
2371     // (Note:  TypeFunc::make has a cache that makes this fast.)
2372     const TypeFunc* tf    = TypeFunc::make(dest_method);
2373     int             nargs = tf->domain()->cnt() - TypeFunc::Parms;
2374     for (int j = 0; j < nargs; j++) {
2375       const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2376       if (targ->basic_type() == T_DOUBLE) {
2377         // If any parameters are doubles, they must be rounded before
2378         // the call, dprecision_rounding does gvn.transform
2379         Node *arg = argument(j);
2380         arg = dprecision_rounding(arg);
2381         set_argument(j, arg);
2382       }
2383     }
2384   }
2385 }
2386 
2387 // rounding for strict float precision conformance
2388 Node* GraphKit::precision_rounding(Node* n) {
2389   if (Matcher::strict_fp_requires_explicit_rounding) {
2390 #ifdef IA32
2391     if (UseSSE == 0) {
2392       return _gvn.transform(new RoundFloatNode(nullptr, n));
2393     }
2394 #else
2395     Unimplemented();
2396 #endif // IA32
2397   }
2398   return n;
2399 }
2400 
2401 // rounding for strict double precision conformance
2402 Node* GraphKit::dprecision_rounding(Node *n) {
2403   if (Matcher::strict_fp_requires_explicit_rounding) {
2404 #ifdef IA32
2405     if (UseSSE < 2) {
2406       return _gvn.transform(new RoundDoubleNode(nullptr, n));
2407     }
2408 #else
2409     Unimplemented();
2410 #endif // IA32
2411   }
2412   return n;
2413 }
2414 
2415 //=============================================================================
2416 // Generate a fast path/slow path idiom.  Graph looks like:
2417 // [foo] indicates that 'foo' is a parameter
2418 //
2419 //              [in]     null
2420 //                 \    /
2421 //                  CmpP
2422 //                  Bool ne
2423 //                   If
2424 //                  /  \
2425 //              True    False-<2>
2426 //              / |
2427 //             /  cast_not_null
2428 //           Load  |    |   ^
2429 //        [fast_test]   |   |
2430 // gvn to   opt_test    |   |
2431 //          /    \      |  <1>
2432 //      True     False  |
2433 //        |         \\  |
2434 //   [slow_call]     \[fast_result]
2435 //    Ctl   Val       \      \
2436 //     |               \      \
2437 //    Catch       <1>   \      \
2438 //   /    \        ^     \      \
2439 //  Ex    No_Ex    |      \      \
2440 //  |       \   \  |       \ <2>  \
2441 //  ...      \  [slow_res] |  |    \   [null_result]
2442 //            \         \--+--+---  |  |
2443 //             \           | /    \ | /
2444 //              --------Region     Phi
2445 //
2446 //=============================================================================
2447 // Code is structured as a series of driver functions all called 'do_XXX' that
2448 // call a set of helper functions.  Helper functions first, then drivers.
2449 
2450 //------------------------------null_check_oop---------------------------------
2451 // Null check oop.  Set null-path control into Region in slot 3.
2452 // Make a cast-not-nullness use the other not-null control.  Return cast.
2453 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2454                                bool never_see_null,
2455                                bool safe_for_replace,
2456                                bool speculative) {
2457   // Initial null check taken path
2458   (*null_control) = top();
2459   Node* cast = null_check_common(value, T_OBJECT, false, null_control, speculative);
2460 
2461   // Generate uncommon_trap:
2462   if (never_see_null && (*null_control) != top()) {
2463     // If we see an unexpected null at a check-cast we record it and force a
2464     // recompile; the offending check-cast will be compiled to handle nulls.
2465     // If we see more than one offending BCI, then all checkcasts in the
2466     // method will be compiled to handle nulls.
2467     PreserveJVMState pjvms(this);
2468     set_control(*null_control);
2469     replace_in_map(value, null());
2470     Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculative);
2471     uncommon_trap(reason,
2472                   Deoptimization::Action_make_not_entrant);
2473     (*null_control) = top();    // null path is dead
2474   }
2475   if ((*null_control) == top() && safe_for_replace) {
2476     replace_in_map(value, cast);
2477   }
2478 
2479   // Cast away null-ness on the result
2480   return cast;
2481 }
2482 
2483 //------------------------------opt_iff----------------------------------------
2484 // Optimize the fast-check IfNode.  Set the fast-path region slot 2.
2485 // Return slow-path control.
2486 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2487   IfNode *opt_iff = _gvn.transform(iff)->as_If();
2488 
2489   // Fast path taken; set region slot 2
2490   Node *fast_taken = _gvn.transform( new IfFalseNode(opt_iff) );
2491   region->init_req(2,fast_taken); // Capture fast-control
2492 
2493   // Fast path not-taken, i.e. slow path
2494   Node *slow_taken = _gvn.transform( new IfTrueNode(opt_iff) );
2495   return slow_taken;
2496 }
2497 
2498 //-----------------------------make_runtime_call-------------------------------
2499 Node* GraphKit::make_runtime_call(int flags,
2500                                   const TypeFunc* call_type, address call_addr,
2501                                   const char* call_name,
2502                                   const TypePtr* adr_type,
2503                                   // The following parms are all optional.
2504                                   // The first null ends the list.
2505                                   Node* parm0, Node* parm1,
2506                                   Node* parm2, Node* parm3,
2507                                   Node* parm4, Node* parm5,
2508                                   Node* parm6, Node* parm7) {
2509   assert(call_addr != nullptr, "must not call null targets");
2510 
2511   // Slow-path call
2512   bool is_leaf = !(flags & RC_NO_LEAF);
2513   bool has_io  = (!is_leaf && !(flags & RC_NO_IO));
2514   if (call_name == nullptr) {
2515     assert(!is_leaf, "must supply name for leaf");
2516     call_name = OptoRuntime::stub_name(call_addr);
2517   }
2518   CallNode* call;
2519   if (!is_leaf) {
2520     call = new CallStaticJavaNode(call_type, call_addr, call_name, adr_type);
2521   } else if (flags & RC_NO_FP) {
2522     call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2523   } else  if (flags & RC_VECTOR){
2524     uint num_bits = call_type->range()->field_at(TypeFunc::Parms)->is_vect()->length_in_bytes() * BitsPerByte;
2525     call = new CallLeafVectorNode(call_type, call_addr, call_name, adr_type, num_bits);
2526   } else {
2527     call = new CallLeafNode(call_type, call_addr, call_name, adr_type);
2528   }
2529 
2530   // The following is similar to set_edges_for_java_call,
2531   // except that the memory effects of the call are restricted to AliasIdxRaw.
2532 
2533   // Slow path call has no side-effects, uses few values
2534   bool wide_in  = !(flags & RC_NARROW_MEM);
2535   bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2536 
2537   Node* prev_mem = nullptr;
2538   if (wide_in) {
2539     prev_mem = set_predefined_input_for_runtime_call(call);
2540   } else {
2541     assert(!wide_out, "narrow in => narrow out");
2542     Node* narrow_mem = memory(adr_type);
2543     prev_mem = set_predefined_input_for_runtime_call(call, narrow_mem);
2544   }
2545 
2546   // Hook each parm in order.  Stop looking at the first null.
2547   if (parm0 != nullptr) { call->init_req(TypeFunc::Parms+0, parm0);
2548   if (parm1 != nullptr) { call->init_req(TypeFunc::Parms+1, parm1);
2549   if (parm2 != nullptr) { call->init_req(TypeFunc::Parms+2, parm2);
2550   if (parm3 != nullptr) { call->init_req(TypeFunc::Parms+3, parm3);
2551   if (parm4 != nullptr) { call->init_req(TypeFunc::Parms+4, parm4);
2552   if (parm5 != nullptr) { call->init_req(TypeFunc::Parms+5, parm5);
2553   if (parm6 != nullptr) { call->init_req(TypeFunc::Parms+6, parm6);
2554   if (parm7 != nullptr) { call->init_req(TypeFunc::Parms+7, parm7);
2555   /* close each nested if ===> */  } } } } } } } }
2556   assert(call->in(call->req()-1) != nullptr, "must initialize all parms");
2557 
2558   if (!is_leaf) {
2559     // Non-leaves can block and take safepoints:
2560     add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2561   }
2562   // Non-leaves can throw exceptions:
2563   if (has_io) {
2564     call->set_req(TypeFunc::I_O, i_o());
2565   }
2566 
2567   if (flags & RC_UNCOMMON) {
2568     // Set the count to a tiny probability.  Cf. Estimate_Block_Frequency.
2569     // (An "if" probability corresponds roughly to an unconditional count.
2570     // Sort of.)
2571     call->set_cnt(PROB_UNLIKELY_MAG(4));
2572   }
2573 
2574   Node* c = _gvn.transform(call);
2575   assert(c == call, "cannot disappear");
2576 
2577   if (wide_out) {
2578     // Slow path call has full side-effects.
2579     set_predefined_output_for_runtime_call(call);
2580   } else {
2581     // Slow path call has few side-effects, and/or sets few values.
2582     set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2583   }
2584 
2585   if (has_io) {
2586     set_i_o(_gvn.transform(new ProjNode(call, TypeFunc::I_O)));
2587   }
2588   return call;
2589 
2590 }
2591 
2592 // i2b
2593 Node* GraphKit::sign_extend_byte(Node* in) {
2594   Node* tmp = _gvn.transform(new LShiftINode(in, _gvn.intcon(24)));
2595   return _gvn.transform(new RShiftINode(tmp, _gvn.intcon(24)));
2596 }
2597 
2598 // i2s
2599 Node* GraphKit::sign_extend_short(Node* in) {
2600   Node* tmp = _gvn.transform(new LShiftINode(in, _gvn.intcon(16)));
2601   return _gvn.transform(new RShiftINode(tmp, _gvn.intcon(16)));
2602 }
2603 
2604 //------------------------------merge_memory-----------------------------------
2605 // Merge memory from one path into the current memory state.
2606 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2607   for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2608     Node* old_slice = mms.force_memory();
2609     Node* new_slice = mms.memory2();
2610     if (old_slice != new_slice) {
2611       PhiNode* phi;
2612       if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) {
2613         if (mms.is_empty()) {
2614           // clone base memory Phi's inputs for this memory slice
2615           assert(old_slice == mms.base_memory(), "sanity");
2616           phi = PhiNode::make(region, nullptr, Type::MEMORY, mms.adr_type(C));
2617           _gvn.set_type(phi, Type::MEMORY);
2618           for (uint i = 1; i < phi->req(); i++) {
2619             phi->init_req(i, old_slice->in(i));
2620           }
2621         } else {
2622           phi = old_slice->as_Phi(); // Phi was generated already
2623         }
2624       } else {
2625         phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2626         _gvn.set_type(phi, Type::MEMORY);
2627       }
2628       phi->set_req(new_path, new_slice);
2629       mms.set_memory(phi);
2630     }
2631   }
2632 }
2633 
2634 //------------------------------make_slow_call_ex------------------------------
2635 // Make the exception handler hookups for the slow call
2636 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) {
2637   if (stopped())  return;
2638 
2639   // Make a catch node with just two handlers:  fall-through and catch-all
2640   Node* i_o  = _gvn.transform( new ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2641   Node* catc = _gvn.transform( new CatchNode(control(), i_o, 2) );
2642   Node* norm = new CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci);
2643   _gvn.set_type_bottom(norm);
2644   C->record_for_igvn(norm);
2645   Node* excp = _gvn.transform( new CatchProjNode(catc, CatchProjNode::catch_all_index,    CatchProjNode::no_handler_bci) );
2646 
2647   { PreserveJVMState pjvms(this);
2648     set_control(excp);
2649     set_i_o(i_o);
2650 
2651     if (excp != top()) {
2652       if (deoptimize) {
2653         // Deoptimize if an exception is caught. Don't construct exception state in this case.
2654         uncommon_trap(Deoptimization::Reason_unhandled,
2655                       Deoptimization::Action_none);
2656       } else {
2657         // Create an exception state also.
2658         // Use an exact type if the caller has a specific exception.
2659         const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2660         Node*       ex_oop  = new CreateExNode(ex_type, control(), i_o);
2661         add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2662       }
2663     }
2664   }
2665 
2666   // Get the no-exception control from the CatchNode.
2667   set_control(norm);
2668 }
2669 
2670 static IfNode* gen_subtype_check_compare(Node* ctrl, Node* in1, Node* in2, BoolTest::mask test, float p, PhaseGVN& gvn, BasicType bt) {
2671   Node* cmp = nullptr;
2672   switch(bt) {
2673   case T_INT: cmp = new CmpINode(in1, in2); break;
2674   case T_ADDRESS: cmp = new CmpPNode(in1, in2); break;
2675   default: fatal("unexpected comparison type %s", type2name(bt));
2676   }
2677   cmp = gvn.transform(cmp);
2678   Node* bol = gvn.transform(new BoolNode(cmp, test));
2679   IfNode* iff = new IfNode(ctrl, bol, p, COUNT_UNKNOWN);
2680   gvn.transform(iff);
2681   if (!bol->is_Con()) gvn.record_for_igvn(iff);
2682   return iff;
2683 }
2684 
2685 //-------------------------------gen_subtype_check-----------------------------
2686 // Generate a subtyping check.  Takes as input the subtype and supertype.
2687 // Returns 2 values: sets the default control() to the true path and returns
2688 // the false path.  Only reads invariant memory; sets no (visible) memory.
2689 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2690 // but that's not exposed to the optimizer.  This call also doesn't take in an
2691 // Object; if you wish to check an Object you need to load the Object's class
2692 // prior to coming here.
2693 Node* Phase::gen_subtype_check(Node* subklass, Node* superklass, Node** ctrl, Node* mem, PhaseGVN& gvn,
2694                                ciMethod* method, int bci) {
2695   Compile* C = gvn.C;
2696   if ((*ctrl)->is_top()) {
2697     return C->top();
2698   }
2699 
2700   // Fast check for identical types, perhaps identical constants.
2701   // The types can even be identical non-constants, in cases
2702   // involving Array.newInstance, Object.clone, etc.
2703   if (subklass == superklass)
2704     return C->top();             // false path is dead; no test needed.
2705 
2706   if (gvn.type(superklass)->singleton()) {
2707     const TypeKlassPtr* superk = gvn.type(superklass)->is_klassptr();
2708     const TypeKlassPtr* subk   = gvn.type(subklass)->is_klassptr();
2709 
2710     // In the common case of an exact superklass, try to fold up the
2711     // test before generating code.  You may ask, why not just generate
2712     // the code and then let it fold up?  The answer is that the generated
2713     // code will necessarily include null checks, which do not always
2714     // completely fold away.  If they are also needless, then they turn
2715     // into a performance loss.  Example:
2716     //    Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2717     // Here, the type of 'fa' is often exact, so the store check
2718     // of fa[1]=x will fold up, without testing the nullness of x.
2719     //
2720     // At macro expansion, we would have already folded the SubTypeCheckNode
2721     // being expanded here because we always perform the static sub type
2722     // check in SubTypeCheckNode::sub() regardless of whether
2723     // StressReflectiveCode is set or not. We can therefore skip this
2724     // static check when StressReflectiveCode is on.
2725     switch (C->static_subtype_check(superk, subk)) {
2726     case Compile::SSC_always_false:
2727       {
2728         Node* always_fail = *ctrl;
2729         *ctrl = gvn.C->top();
2730         return always_fail;
2731       }
2732     case Compile::SSC_always_true:
2733       return C->top();
2734     case Compile::SSC_easy_test:
2735       {
2736         // Just do a direct pointer compare and be done.
2737         IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_STATIC_FREQUENT, gvn, T_ADDRESS);
2738         *ctrl = gvn.transform(new IfTrueNode(iff));
2739         return gvn.transform(new IfFalseNode(iff));
2740       }
2741     case Compile::SSC_full_test:
2742       break;
2743     default:
2744       ShouldNotReachHere();
2745     }
2746   }
2747 
2748   // %%% Possible further optimization:  Even if the superklass is not exact,
2749   // if the subklass is the unique subtype of the superklass, the check
2750   // will always succeed.  We could leave a dependency behind to ensure this.
2751 
2752   // First load the super-klass's check-offset
2753   Node *p1 = gvn.transform(new AddPNode(superklass, superklass, gvn.MakeConX(in_bytes(Klass::super_check_offset_offset()))));
2754   Node* m = C->immutable_memory();
2755   Node *chk_off = gvn.transform(new LoadINode(nullptr, m, p1, gvn.type(p1)->is_ptr(), TypeInt::INT, MemNode::unordered));
2756   int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2757   const TypeInt* chk_off_t = chk_off->Value(&gvn)->isa_int();
2758   int chk_off_con = (chk_off_t != nullptr && chk_off_t->is_con()) ? chk_off_t->get_con() : cacheoff_con;
2759   bool might_be_cache = (chk_off_con == cacheoff_con);
2760 
2761   // Load from the sub-klass's super-class display list, or a 1-word cache of
2762   // the secondary superclass list, or a failing value with a sentinel offset
2763   // if the super-klass is an interface or exceptionally deep in the Java
2764   // hierarchy and we have to scan the secondary superclass list the hard way.
2765   // Worst-case type is a little odd: null is allowed as a result (usually
2766   // klass loads can never produce a null).
2767   Node *chk_off_X = chk_off;
2768 #ifdef _LP64
2769   chk_off_X = gvn.transform(new ConvI2LNode(chk_off_X));
2770 #endif
2771   Node *p2 = gvn.transform(new AddPNode(subklass,subklass,chk_off_X));
2772   // For some types like interfaces the following loadKlass is from a 1-word
2773   // cache which is mutable so can't use immutable memory.  Other
2774   // types load from the super-class display table which is immutable.
2775   Node *kmem = C->immutable_memory();
2776   // secondary_super_cache is not immutable but can be treated as such because:
2777   // - no ideal node writes to it in a way that could cause an
2778   //   incorrect/missed optimization of the following Load.
2779   // - it's a cache so, worse case, not reading the latest value
2780   //   wouldn't cause incorrect execution
2781   if (might_be_cache && mem != nullptr) {
2782     kmem = mem->is_MergeMem() ? mem->as_MergeMem()->memory_at(C->get_alias_index(gvn.type(p2)->is_ptr())) : mem;
2783   }
2784   Node *nkls = gvn.transform(LoadKlassNode::make(gvn, nullptr, kmem, p2, gvn.type(p2)->is_ptr(), TypeInstKlassPtr::OBJECT_OR_NULL));
2785 
2786   // Compile speed common case: ARE a subtype and we canNOT fail
2787   if (superklass == nkls) {
2788     return C->top();             // false path is dead; no test needed.
2789   }
2790 
2791   // Gather the various success & failures here
2792   RegionNode* r_not_subtype = new RegionNode(3);
2793   gvn.record_for_igvn(r_not_subtype);
2794   RegionNode* r_ok_subtype = new RegionNode(4);
2795   gvn.record_for_igvn(r_ok_subtype);
2796 
2797   // If we might perform an expensive check, first try to take advantage of profile data that was attached to the
2798   // SubTypeCheck node
2799   if (might_be_cache && method != nullptr && VM_Version::profile_all_receivers_at_type_check()) {
2800     ciCallProfile profile = method->call_profile_at_bci(bci);
2801     float total_prob = 0;
2802     for (int i = 0; profile.has_receiver(i); ++i) {
2803       float prob = profile.receiver_prob(i);
2804       total_prob += prob;
2805     }
2806     if (total_prob * 100. >= TypeProfileSubTypeCheckCommonThreshold) {
2807       const TypeKlassPtr* superk = gvn.type(superklass)->is_klassptr();
2808       for (int i = 0; profile.has_receiver(i); ++i) {
2809         ciKlass* klass = profile.receiver(i);
2810         const TypeKlassPtr* klass_t = TypeKlassPtr::make(klass);
2811         Compile::SubTypeCheckResult result = C->static_subtype_check(superk, klass_t);
2812         if (result != Compile::SSC_always_true && result != Compile::SSC_always_false) {
2813           continue;
2814         }
2815         float prob = profile.receiver_prob(i);
2816         ConNode* klass_node = gvn.makecon(klass_t);
2817         IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, klass_node, BoolTest::eq, prob, gvn, T_ADDRESS);
2818         Node* iftrue = gvn.transform(new IfTrueNode(iff));
2819 
2820         if (result == Compile::SSC_always_true) {
2821           r_ok_subtype->add_req(iftrue);
2822         } else {
2823           assert(result == Compile::SSC_always_false, "");
2824           r_not_subtype->add_req(iftrue);
2825         }
2826         *ctrl = gvn.transform(new IfFalseNode(iff));
2827       }
2828     }
2829   }
2830 
2831   // See if we get an immediate positive hit.  Happens roughly 83% of the
2832   // time.  Test to see if the value loaded just previously from the subklass
2833   // is exactly the superklass.
2834   IfNode *iff1 = gen_subtype_check_compare(*ctrl, superklass, nkls, BoolTest::eq, PROB_LIKELY(0.83f), gvn, T_ADDRESS);
2835   Node *iftrue1 = gvn.transform( new IfTrueNode (iff1));
2836   *ctrl = gvn.transform(new IfFalseNode(iff1));
2837 
2838   // Compile speed common case: Check for being deterministic right now.  If
2839   // chk_off is a constant and not equal to cacheoff then we are NOT a
2840   // subklass.  In this case we need exactly the 1 test above and we can
2841   // return those results immediately.
2842   if (!might_be_cache) {
2843     Node* not_subtype_ctrl = *ctrl;
2844     *ctrl = iftrue1; // We need exactly the 1 test above
2845     PhaseIterGVN* igvn = gvn.is_IterGVN();
2846     if (igvn != nullptr) {
2847       igvn->remove_globally_dead_node(r_ok_subtype);
2848       igvn->remove_globally_dead_node(r_not_subtype);
2849     }
2850     return not_subtype_ctrl;
2851   }
2852 
2853   r_ok_subtype->init_req(1, iftrue1);
2854 
2855   // Check for immediate negative hit.  Happens roughly 11% of the time (which
2856   // is roughly 63% of the remaining cases).  Test to see if the loaded
2857   // check-offset points into the subklass display list or the 1-element
2858   // cache.  If it points to the display (and NOT the cache) and the display
2859   // missed then it's not a subtype.
2860   Node *cacheoff = gvn.intcon(cacheoff_con);
2861   IfNode *iff2 = gen_subtype_check_compare(*ctrl, chk_off, cacheoff, BoolTest::ne, PROB_LIKELY(0.63f), gvn, T_INT);
2862   r_not_subtype->init_req(1, gvn.transform(new IfTrueNode (iff2)));
2863   *ctrl = gvn.transform(new IfFalseNode(iff2));
2864 
2865   // Check for self.  Very rare to get here, but it is taken 1/3 the time.
2866   // No performance impact (too rare) but allows sharing of secondary arrays
2867   // which has some footprint reduction.
2868   IfNode *iff3 = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_LIKELY(0.36f), gvn, T_ADDRESS);
2869   r_ok_subtype->init_req(2, gvn.transform(new IfTrueNode(iff3)));
2870   *ctrl = gvn.transform(new IfFalseNode(iff3));
2871 
2872   // -- Roads not taken here: --
2873   // We could also have chosen to perform the self-check at the beginning
2874   // of this code sequence, as the assembler does.  This would not pay off
2875   // the same way, since the optimizer, unlike the assembler, can perform
2876   // static type analysis to fold away many successful self-checks.
2877   // Non-foldable self checks work better here in second position, because
2878   // the initial primary superclass check subsumes a self-check for most
2879   // types.  An exception would be a secondary type like array-of-interface,
2880   // which does not appear in its own primary supertype display.
2881   // Finally, we could have chosen to move the self-check into the
2882   // PartialSubtypeCheckNode, and from there out-of-line in a platform
2883   // dependent manner.  But it is worthwhile to have the check here,
2884   // where it can be perhaps be optimized.  The cost in code space is
2885   // small (register compare, branch).
2886 
2887   // Now do a linear scan of the secondary super-klass array.  Again, no real
2888   // performance impact (too rare) but it's gotta be done.
2889   // Since the code is rarely used, there is no penalty for moving it
2890   // out of line, and it can only improve I-cache density.
2891   // The decision to inline or out-of-line this final check is platform
2892   // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2893   Node* psc = gvn.transform(
2894     new PartialSubtypeCheckNode(*ctrl, subklass, superklass));
2895 
2896   IfNode *iff4 = gen_subtype_check_compare(*ctrl, psc, gvn.zerocon(T_OBJECT), BoolTest::ne, PROB_FAIR, gvn, T_ADDRESS);
2897   r_not_subtype->init_req(2, gvn.transform(new IfTrueNode (iff4)));
2898   r_ok_subtype ->init_req(3, gvn.transform(new IfFalseNode(iff4)));
2899 
2900   // Return false path; set default control to true path.
2901   *ctrl = gvn.transform(r_ok_subtype);
2902   return gvn.transform(r_not_subtype);
2903 }
2904 
2905 Node* GraphKit::gen_subtype_check(Node* obj_or_subklass, Node* superklass) {
2906   bool expand_subtype_check = C->post_loop_opts_phase(); // macro node expansion is over
2907   if (expand_subtype_check) {
2908     MergeMemNode* mem = merged_memory();
2909     Node* ctrl = control();
2910     Node* subklass = obj_or_subklass;
2911     if (!_gvn.type(obj_or_subklass)->isa_klassptr()) {
2912       subklass = load_object_klass(obj_or_subklass);
2913     }
2914 
2915     Node* n = Phase::gen_subtype_check(subklass, superklass, &ctrl, mem, _gvn, method(), bci());
2916     set_control(ctrl);
2917     return n;
2918   }
2919 
2920   Node* check = _gvn.transform(new SubTypeCheckNode(C, obj_or_subklass, superklass, method(), bci()));
2921   Node* bol = _gvn.transform(new BoolNode(check, BoolTest::eq));
2922   IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN);
2923   set_control(_gvn.transform(new IfTrueNode(iff)));
2924   return _gvn.transform(new IfFalseNode(iff));
2925 }
2926 
2927 // Profile-driven exact type check:
2928 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2929                                     float prob,
2930                                     Node* *casted_receiver) {
2931   assert(!klass->is_interface(), "no exact type check on interfaces");
2932 
2933   const TypeKlassPtr* tklass = TypeKlassPtr::make(klass, Type::trust_interfaces);
2934   Node* recv_klass = load_object_klass(receiver);
2935   Node* want_klass = makecon(tklass);
2936   Node* cmp = _gvn.transform(new CmpPNode(recv_klass, want_klass));
2937   Node* bol = _gvn.transform(new BoolNode(cmp, BoolTest::eq));
2938   IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2939   set_control( _gvn.transform(new IfTrueNode (iff)));
2940   Node* fail = _gvn.transform(new IfFalseNode(iff));
2941 
2942   if (!stopped()) {
2943     const TypeOopPtr* receiver_type = _gvn.type(receiver)->isa_oopptr();
2944     const TypeOopPtr* recvx_type = tklass->as_instance_type();
2945     assert(recvx_type->klass_is_exact(), "");
2946 
2947     if (!receiver_type->higher_equal(recvx_type)) { // ignore redundant casts
2948       // Subsume downstream occurrences of receiver with a cast to
2949       // recv_xtype, since now we know what the type will be.
2950       Node* cast = new CheckCastPPNode(control(), receiver, recvx_type);
2951       (*casted_receiver) = _gvn.transform(cast);
2952       assert(!(*casted_receiver)->is_top(), "that path should be unreachable");
2953       // (User must make the replace_in_map call.)
2954     }
2955   }
2956 
2957   return fail;
2958 }
2959 
2960 //------------------------------subtype_check_receiver-------------------------
2961 Node* GraphKit::subtype_check_receiver(Node* receiver, ciKlass* klass,
2962                                        Node** casted_receiver) {
2963   const TypeKlassPtr* tklass = TypeKlassPtr::make(klass, Type::trust_interfaces)->try_improve();
2964   Node* want_klass = makecon(tklass);
2965 
2966   Node* slow_ctl = gen_subtype_check(receiver, want_klass);
2967 
2968   // Ignore interface type information until interface types are properly tracked.
2969   if (!stopped() && !klass->is_interface()) {
2970     const TypeOopPtr* receiver_type = _gvn.type(receiver)->isa_oopptr();
2971     const TypeOopPtr* recv_type = tklass->cast_to_exactness(false)->is_klassptr()->as_instance_type();
2972     if (!receiver_type->higher_equal(recv_type)) { // ignore redundant casts
2973       Node* cast = new CheckCastPPNode(control(), receiver, recv_type);
2974       (*casted_receiver) = _gvn.transform(cast);
2975     }
2976   }
2977 
2978   return slow_ctl;
2979 }
2980 
2981 //------------------------------seems_never_null-------------------------------
2982 // Use null_seen information if it is available from the profile.
2983 // If we see an unexpected null at a type check we record it and force a
2984 // recompile; the offending check will be recompiled to handle nulls.
2985 // If we see several offending BCIs, then all checks in the
2986 // method will be recompiled.
2987 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data, bool& speculating) {
2988   speculating = !_gvn.type(obj)->speculative_maybe_null();
2989   Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculating);
2990   if (UncommonNullCast               // Cutout for this technique
2991       && obj != null()               // And not the -Xcomp stupid case?
2992       && !too_many_traps(reason)
2993       ) {
2994     if (speculating) {
2995       return true;
2996     }
2997     if (data == nullptr)
2998       // Edge case:  no mature data.  Be optimistic here.
2999       return true;
3000     // If the profile has not seen a null, assume it won't happen.
3001     assert(java_bc() == Bytecodes::_checkcast ||
3002            java_bc() == Bytecodes::_instanceof ||
3003            java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
3004     return !data->as_BitData()->null_seen();
3005   }
3006   speculating = false;
3007   return false;
3008 }
3009 
3010 void GraphKit::guard_klass_is_initialized(Node* klass) {
3011   assert(ClassInitBarrierMode > 0, "no barriers");
3012   int init_state_off = in_bytes(InstanceKlass::init_state_offset());
3013   Node* adr = basic_plus_adr(top(), klass, init_state_off);
3014   Node* init_state = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3015                                     adr->bottom_type()->is_ptr(), TypeInt::BYTE,
3016                                     T_BYTE, MemNode::unordered);
3017   init_state = _gvn.transform(init_state);
3018 
3019   Node* initialized_state = makecon(TypeInt::make(InstanceKlass::fully_initialized));
3020 
3021   Node* chk = _gvn.transform(new CmpINode(initialized_state, init_state));
3022   Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3023 
3024   switch (ClassInitBarrierMode) {
3025     case 1: { // uncommon trap on slow path
3026       BuildCutout unless(this, tst, PROB_MAX);
3027       // Do not deoptimize this nmethod. Go to Interpreter to initialize class.
3028       uncommon_trap(Deoptimization::Reason_uninitialized, Deoptimization::Action_none);
3029       break;
3030     }
3031     case 2: { // runtime call on slow path
3032       if (StressClassInitBarriers) {
3033         tst = makecon(TypeInt::ZERO); // always go through slow path
3034       }
3035       IfNode* iff = create_and_xform_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
3036 //    IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
3037 
3038       RegionNode* r = new RegionNode(3);
3039       r->init_req(1, _gvn.transform(new IfTrueNode(iff)));
3040 
3041       set_control(_gvn.transform(new IfFalseNode(iff)));
3042 
3043       if (!stopped()) {
3044         kill_dead_locals();
3045 
3046         Node* call = make_runtime_call(RC_NO_LEAF,
3047                                        OptoRuntime::class_init_barrier_Type(),
3048                                        OptoRuntime::class_init_barrier_Java(),
3049                                        nullptr, TypePtr::BOTTOM,
3050                                        klass);
3051         // Deoptimization during class init barrier execution should trigger current bytecode reexecution.
3052         call->jvms()->set_should_reexecute(true);
3053 
3054         // FIXME: deoptimize for now. deoptimize=false doesn't work with late inlining yet.
3055         // Parse::create_entry_map() introduces a barrier which uses distinct JVM state (*before* call).
3056         // Compilation fails when distinct exception states are combined.
3057         make_slow_call_ex(call, env()->Throwable_klass(), /*separate_io_proj=*/true, /*deoptimize=*/true);
3058 
3059         Node* fast_io  = call->in(TypeFunc::I_O);
3060         Node* fast_mem = call->in(TypeFunc::Memory);
3061         // These two phis are pre-filled with copies of of the fast IO and Memory
3062         Node* io_phi   = PhiNode::make(r, fast_io,  Type::ABIO);
3063         Node* mem_phi  = PhiNode::make(r, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
3064 
3065         r->init_req(2, control());
3066         io_phi->init_req(2, i_o());
3067         mem_phi->init_req(2, reset_memory());
3068 
3069         set_all_memory(_gvn.transform(mem_phi));
3070         set_i_o(_gvn.transform(io_phi));
3071       } else {
3072         r->init_req(2, top());
3073       }
3074       set_control(_gvn.transform(r));
3075       break;
3076     }
3077 
3078     default: fatal("unknown barrier mode: %d", ClassInitBarrierMode);
3079   }
3080   C->set_has_clinit_barriers(true);
3081 }
3082 
3083 void GraphKit::guard_klass_being_initialized(Node* klass) {
3084   int init_state_off = in_bytes(InstanceKlass::init_state_offset());
3085   Node* adr = basic_plus_adr(top(), klass, init_state_off);
3086   Node* init_state = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3087                                     adr->bottom_type()->is_ptr(), TypeInt::BYTE,
3088                                     T_BYTE, MemNode::acquire);
3089   init_state = _gvn.transform(init_state);
3090 
3091   Node* being_initialized_state = makecon(TypeInt::make(InstanceKlass::being_initialized));
3092 
3093   Node* chk = _gvn.transform(new CmpINode(being_initialized_state, init_state));
3094   Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3095 
3096   { BuildCutout unless(this, tst, PROB_MAX);
3097     uncommon_trap(Deoptimization::Reason_initialized, Deoptimization::Action_reinterpret);
3098   }
3099 }
3100 
3101 void GraphKit::guard_init_thread(Node* klass) {
3102   int init_thread_off = in_bytes(InstanceKlass::init_thread_offset());
3103   Node* adr = basic_plus_adr(top(), klass, init_thread_off);
3104 
3105   Node* init_thread = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3106                                      adr->bottom_type()->is_ptr(), TypePtr::NOTNULL,
3107                                      T_ADDRESS, MemNode::unordered);
3108   init_thread = _gvn.transform(init_thread);
3109 
3110   Node* cur_thread = _gvn.transform(new ThreadLocalNode());
3111 
3112   Node* chk = _gvn.transform(new CmpPNode(cur_thread, init_thread));
3113   Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3114 
3115   { BuildCutout unless(this, tst, PROB_MAX);
3116     uncommon_trap(Deoptimization::Reason_uninitialized, Deoptimization::Action_none);
3117   }
3118 }
3119 
3120 void GraphKit::clinit_barrier(ciInstanceKlass* ik, ciMethod* context) {
3121   if (C->do_clinit_barriers()) {
3122     Node* klass = makecon(TypeKlassPtr::make(ik, Type::trust_interfaces));
3123     guard_klass_is_initialized(klass);
3124     return;
3125   }
3126   if (ik->is_being_initialized()) {
3127     if (C->needs_clinit_barrier(ik, context)) {
3128       Node* klass = makecon(TypeKlassPtr::make(ik, Type::trust_interfaces));
3129       guard_klass_being_initialized(klass);
3130       guard_init_thread(klass);
3131       insert_mem_bar(Op_MemBarCPUOrder);
3132     }
3133   } else if (ik->is_initialized()) {
3134     return; // no barrier needed
3135   } else {
3136     uncommon_trap(Deoptimization::Reason_uninitialized,
3137                   Deoptimization::Action_reinterpret,
3138                   nullptr);
3139   }
3140 }
3141 
3142 //------------------------maybe_cast_profiled_receiver-------------------------
3143 // If the profile has seen exactly one type, narrow to exactly that type.
3144 // Subsequent type checks will always fold up.
3145 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
3146                                              const TypeKlassPtr* require_klass,
3147                                              ciKlass* spec_klass,
3148                                              bool safe_for_replace) {
3149   if (!UseTypeProfile || !TypeProfileCasts) return nullptr;
3150 
3151   Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != nullptr);
3152 
3153   // Make sure we haven't already deoptimized from this tactic.
3154   if (too_many_traps_or_recompiles(reason))
3155     return nullptr;
3156 
3157   // (No, this isn't a call, but it's enough like a virtual call
3158   // to use the same ciMethod accessor to get the profile info...)
3159   // If we have a speculative type use it instead of profiling (which
3160   // may not help us)
3161   ciKlass* exact_kls = spec_klass == nullptr ? profile_has_unique_klass() : spec_klass;
3162   if (exact_kls != nullptr) {// no cast failures here
3163     if (require_klass == nullptr ||
3164         C->static_subtype_check(require_klass, TypeKlassPtr::make(exact_kls, Type::trust_interfaces)) == Compile::SSC_always_true) {
3165       // If we narrow the type to match what the type profile sees or
3166       // the speculative type, we can then remove the rest of the
3167       // cast.
3168       // This is a win, even if the exact_kls is very specific,
3169       // because downstream operations, such as method calls,
3170       // will often benefit from the sharper type.
3171       Node* exact_obj = not_null_obj; // will get updated in place...
3172       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
3173                                             &exact_obj);
3174       { PreserveJVMState pjvms(this);
3175         set_control(slow_ctl);
3176         uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile);
3177       }
3178       if (safe_for_replace) {
3179         replace_in_map(not_null_obj, exact_obj);
3180       }
3181       return exact_obj;
3182     }
3183     // assert(ssc == Compile::SSC_always_true)... except maybe the profile lied to us.
3184   }
3185 
3186   return nullptr;
3187 }
3188 
3189 /**
3190  * Cast obj to type and emit guard unless we had too many traps here
3191  * already
3192  *
3193  * @param obj       node being casted
3194  * @param type      type to cast the node to
3195  * @param not_null  true if we know node cannot be null
3196  */
3197 Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
3198                                         ciKlass* type,
3199                                         bool not_null) {
3200   if (stopped()) {
3201     return obj;
3202   }
3203 
3204   // type is null if profiling tells us this object is always null
3205   if (type != nullptr) {
3206     Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
3207     Deoptimization::DeoptReason null_reason = Deoptimization::Reason_speculate_null_check;
3208 
3209     if (!too_many_traps_or_recompiles(null_reason) &&
3210         !too_many_traps_or_recompiles(class_reason)) {
3211       Node* not_null_obj = nullptr;
3212       // not_null is true if we know the object is not null and
3213       // there's no need for a null check
3214       if (!not_null) {
3215         Node* null_ctl = top();
3216         not_null_obj = null_check_oop(obj, &null_ctl, true, true, true);
3217         assert(null_ctl->is_top(), "no null control here");
3218       } else {
3219         not_null_obj = obj;
3220       }
3221 
3222       Node* exact_obj = not_null_obj;
3223       ciKlass* exact_kls = type;
3224       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
3225                                             &exact_obj);
3226       {
3227         PreserveJVMState pjvms(this);
3228         set_control(slow_ctl);
3229         uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile);
3230       }
3231       replace_in_map(not_null_obj, exact_obj);
3232       obj = exact_obj;
3233     }
3234   } else {
3235     if (!too_many_traps_or_recompiles(Deoptimization::Reason_null_assert)) {
3236       Node* exact_obj = null_assert(obj);
3237       replace_in_map(obj, exact_obj);
3238       obj = exact_obj;
3239     }
3240   }
3241   return obj;
3242 }
3243 
3244 //-------------------------------gen_instanceof--------------------------------
3245 // Generate an instance-of idiom.  Used by both the instance-of bytecode
3246 // and the reflective instance-of call.
3247 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
3248   kill_dead_locals();           // Benefit all the uncommon traps
3249   assert( !stopped(), "dead parse path should be checked in callers" );
3250   assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
3251          "must check for not-null not-dead klass in callers");
3252 
3253   // Make the merge point
3254   enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
3255   RegionNode* region = new RegionNode(PATH_LIMIT);
3256   Node*       phi    = new PhiNode(region, TypeInt::BOOL);
3257   C->set_has_split_ifs(true); // Has chance for split-if optimization
3258 
3259   ciProfileData* data = nullptr;
3260   if (java_bc() == Bytecodes::_instanceof) {  // Only for the bytecode
3261     data = method()->method_data()->bci_to_data(bci());
3262   }
3263   bool speculative_not_null = false;
3264   bool never_see_null = (ProfileDynamicTypes  // aggressive use of profile
3265                          && seems_never_null(obj, data, speculative_not_null));
3266 
3267   // Null check; get casted pointer; set region slot 3
3268   Node* null_ctl = top();
3269   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3270 
3271   // If not_null_obj is dead, only null-path is taken
3272   if (stopped()) {              // Doing instance-of on a null?
3273     set_control(null_ctl);
3274     return intcon(0);
3275   }
3276   region->init_req(_null_path, null_ctl);
3277   phi   ->init_req(_null_path, intcon(0)); // Set null path value
3278   if (null_ctl == top()) {
3279     // Do this eagerly, so that pattern matches like is_diamond_phi
3280     // will work even during parsing.
3281     assert(_null_path == PATH_LIMIT-1, "delete last");
3282     region->del_req(_null_path);
3283     phi   ->del_req(_null_path);
3284   }
3285 
3286   // Do we know the type check always succeed?
3287   bool known_statically = false;
3288   if (_gvn.type(superklass)->singleton()) {
3289     const TypeKlassPtr* superk = _gvn.type(superklass)->is_klassptr();
3290     const TypeKlassPtr* subk = _gvn.type(obj)->is_oopptr()->as_klass_type();
3291     if (subk->is_loaded()) {
3292       int static_res = C->static_subtype_check(superk, subk);
3293       known_statically = (static_res == Compile::SSC_always_true || static_res == Compile::SSC_always_false);
3294     }
3295   }
3296 
3297   if (!known_statically) {
3298     const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3299     // We may not have profiling here or it may not help us. If we
3300     // have a speculative type use it to perform an exact cast.
3301     ciKlass* spec_obj_type = obj_type->speculative_type();
3302     if (spec_obj_type != nullptr || (ProfileDynamicTypes && data != nullptr)) {
3303       Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, nullptr, spec_obj_type, safe_for_replace);
3304       if (stopped()) {            // Profile disagrees with this path.
3305         set_control(null_ctl);    // Null is the only remaining possibility.
3306         return intcon(0);
3307       }
3308       if (cast_obj != nullptr) {
3309         not_null_obj = cast_obj;
3310       }
3311     }
3312   }
3313 
3314   // Generate the subtype check
3315   Node* not_subtype_ctrl = gen_subtype_check(not_null_obj, superklass);
3316 
3317   // Plug in the success path to the general merge in slot 1.
3318   region->init_req(_obj_path, control());
3319   phi   ->init_req(_obj_path, intcon(1));
3320 
3321   // Plug in the failing path to the general merge in slot 2.
3322   region->init_req(_fail_path, not_subtype_ctrl);
3323   phi   ->init_req(_fail_path, intcon(0));
3324 
3325   // Return final merged results
3326   set_control( _gvn.transform(region) );
3327   record_for_igvn(region);
3328 
3329   // If we know the type check always succeeds then we don't use the
3330   // profiling data at this bytecode. Don't lose it, feed it to the
3331   // type system as a speculative type.
3332   if (safe_for_replace) {
3333     Node* casted_obj = record_profiled_receiver_for_speculation(obj);
3334     replace_in_map(obj, casted_obj);
3335   }
3336 
3337   return _gvn.transform(phi);
3338 }
3339 
3340 //-------------------------------gen_checkcast---------------------------------
3341 // Generate a checkcast idiom.  Used by both the checkcast bytecode and the
3342 // array store bytecode.  Stack must be as-if BEFORE doing the bytecode so the
3343 // uncommon-trap paths work.  Adjust stack after this call.
3344 // If failure_control is supplied and not null, it is filled in with
3345 // the control edge for the cast failure.  Otherwise, an appropriate
3346 // uncommon trap or exception is thrown.
3347 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
3348                               Node* *failure_control) {
3349   kill_dead_locals();           // Benefit all the uncommon traps
3350   const TypeKlassPtr* klass_ptr_type = _gvn.type(superklass)->is_klassptr();
3351   const TypeKlassPtr* improved_klass_ptr_type = klass_ptr_type->try_improve();
3352   const TypeOopPtr* toop = improved_klass_ptr_type->cast_to_exactness(false)->as_instance_type();
3353 
3354   // Fast cutout:  Check the case that the cast is vacuously true.
3355   // This detects the common cases where the test will short-circuit
3356   // away completely.  We do this before we perform the null check,
3357   // because if the test is going to turn into zero code, we don't
3358   // want a residual null check left around.  (Causes a slowdown,
3359   // for example, in some objArray manipulations, such as a[i]=a[j].)
3360   if (improved_klass_ptr_type->singleton()) {
3361     const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
3362     if (objtp != nullptr) {
3363       switch (C->static_subtype_check(improved_klass_ptr_type, objtp->as_klass_type())) {
3364       case Compile::SSC_always_true:
3365         // If we know the type check always succeed then we don't use
3366         // the profiling data at this bytecode. Don't lose it, feed it
3367         // to the type system as a speculative type.
3368         return record_profiled_receiver_for_speculation(obj);
3369       case Compile::SSC_always_false:
3370         // It needs a null check because a null will *pass* the cast check.
3371         // A non-null value will always produce an exception.
3372         if (!objtp->maybe_null()) {
3373           bool is_aastore = (java_bc() == Bytecodes::_aastore);
3374           Deoptimization::DeoptReason reason = is_aastore ?
3375             Deoptimization::Reason_array_check : Deoptimization::Reason_class_check;
3376           builtin_throw(reason);
3377           return top();
3378         } else if (!too_many_traps_or_recompiles(Deoptimization::Reason_null_assert)) {
3379           return null_assert(obj);
3380         }
3381         break; // Fall through to full check
3382       default:
3383         break;
3384       }
3385     }
3386   }
3387 
3388   ciProfileData* data = nullptr;
3389   bool safe_for_replace = false;
3390   if (failure_control == nullptr) {        // use MDO in regular case only
3391     assert(java_bc() == Bytecodes::_aastore ||
3392            java_bc() == Bytecodes::_checkcast,
3393            "interpreter profiles type checks only for these BCs");
3394     data = method()->method_data()->bci_to_data(bci());
3395     safe_for_replace = true;
3396   }
3397 
3398   // Make the merge point
3399   enum { _obj_path = 1, _null_path, PATH_LIMIT };
3400   RegionNode* region = new RegionNode(PATH_LIMIT);
3401   Node*       phi    = new PhiNode(region, toop);
3402   C->set_has_split_ifs(true); // Has chance for split-if optimization
3403 
3404   // Use null-cast information if it is available
3405   bool speculative_not_null = false;
3406   bool never_see_null = ((failure_control == nullptr)  // regular case only
3407                          && seems_never_null(obj, data, speculative_not_null));
3408 
3409   // Null check; get casted pointer; set region slot 3
3410   Node* null_ctl = top();
3411   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3412 
3413   // If not_null_obj is dead, only null-path is taken
3414   if (stopped()) {              // Doing instance-of on a null?
3415     set_control(null_ctl);
3416     return null();
3417   }
3418   region->init_req(_null_path, null_ctl);
3419   phi   ->init_req(_null_path, null());  // Set null path value
3420   if (null_ctl == top()) {
3421     // Do this eagerly, so that pattern matches like is_diamond_phi
3422     // will work even during parsing.
3423     assert(_null_path == PATH_LIMIT-1, "delete last");
3424     region->del_req(_null_path);
3425     phi   ->del_req(_null_path);
3426   }
3427 
3428   Node* cast_obj = nullptr;
3429   if (improved_klass_ptr_type->klass_is_exact()) {
3430     // The following optimization tries to statically cast the speculative type of the object
3431     // (for example obtained during profiling) to the type of the superklass and then do a
3432     // dynamic check that the type of the object is what we expect. To work correctly
3433     // for checkcast and aastore the type of superklass should be exact.
3434     const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3435     // We may not have profiling here or it may not help us. If we have
3436     // a speculative type use it to perform an exact cast.
3437     ciKlass* spec_obj_type = obj_type->speculative_type();
3438     if (spec_obj_type != nullptr || data != nullptr) {
3439       cast_obj = maybe_cast_profiled_receiver(not_null_obj, improved_klass_ptr_type, spec_obj_type, safe_for_replace);
3440       if (cast_obj != nullptr) {
3441         if (failure_control != nullptr) // failure is now impossible
3442           (*failure_control) = top();
3443         // adjust the type of the phi to the exact klass:
3444         phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3445       }
3446     }
3447   }
3448 
3449   if (cast_obj == nullptr) {
3450     // Generate the subtype check
3451     Node* improved_superklass = superklass;
3452     if (improved_klass_ptr_type != klass_ptr_type && improved_klass_ptr_type->singleton()) {
3453       improved_superklass = makecon(improved_klass_ptr_type);
3454     }
3455     Node* not_subtype_ctrl = gen_subtype_check(not_null_obj, improved_superklass);
3456 
3457     // Plug in success path into the merge
3458     cast_obj = _gvn.transform(new CheckCastPPNode(control(), not_null_obj, toop));
3459     // Failure path ends in uncommon trap (or may be dead - failure impossible)
3460     if (failure_control == nullptr) {
3461       if (not_subtype_ctrl != top()) { // If failure is possible
3462         PreserveJVMState pjvms(this);
3463         set_control(not_subtype_ctrl);
3464         bool is_aastore = (java_bc() == Bytecodes::_aastore);
3465         Deoptimization::DeoptReason reason = is_aastore ?
3466           Deoptimization::Reason_array_check : Deoptimization::Reason_class_check;
3467         builtin_throw(reason);
3468       }
3469     } else {
3470       (*failure_control) = not_subtype_ctrl;
3471     }
3472   }
3473 
3474   region->init_req(_obj_path, control());
3475   phi   ->init_req(_obj_path, cast_obj);
3476 
3477   // A merge of null or Casted-NotNull obj
3478   Node* res = _gvn.transform(phi);
3479 
3480   // Note I do NOT always 'replace_in_map(obj,result)' here.
3481   //  if( tk->klass()->can_be_primary_super()  )
3482     // This means that if I successfully store an Object into an array-of-String
3483     // I 'forget' that the Object is really now known to be a String.  I have to
3484     // do this because we don't have true union types for interfaces - if I store
3485     // a Baz into an array-of-Interface and then tell the optimizer it's an
3486     // Interface, I forget that it's also a Baz and cannot do Baz-like field
3487     // references to it.  FIX THIS WHEN UNION TYPES APPEAR!
3488   //  replace_in_map( obj, res );
3489 
3490   // Return final merged results
3491   set_control( _gvn.transform(region) );
3492   record_for_igvn(region);
3493 
3494   return record_profiled_receiver_for_speculation(res);
3495 }
3496 
3497 //------------------------------next_monitor-----------------------------------
3498 // What number should be given to the next monitor?
3499 int GraphKit::next_monitor() {
3500   int current = jvms()->monitor_depth()* C->sync_stack_slots();
3501   int next = current + C->sync_stack_slots();
3502   // Keep the toplevel high water mark current:
3503   if (C->fixed_slots() < next)  C->set_fixed_slots(next);
3504   return current;
3505 }
3506 
3507 //------------------------------insert_mem_bar---------------------------------
3508 // Memory barrier to avoid floating things around
3509 // The membar serves as a pinch point between both control and all memory slices.
3510 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3511   MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3512   mb->init_req(TypeFunc::Control, control());
3513   mb->init_req(TypeFunc::Memory,  reset_memory());
3514   Node* membar = _gvn.transform(mb);
3515   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3516   set_all_memory_call(membar);
3517   return membar;
3518 }
3519 
3520 //-------------------------insert_mem_bar_volatile----------------------------
3521 // Memory barrier to avoid floating things around
3522 // The membar serves as a pinch point between both control and memory(alias_idx).
3523 // If you want to make a pinch point on all memory slices, do not use this
3524 // function (even with AliasIdxBot); use insert_mem_bar() instead.
3525 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3526   // When Parse::do_put_xxx updates a volatile field, it appends a series
3527   // of MemBarVolatile nodes, one for *each* volatile field alias category.
3528   // The first membar is on the same memory slice as the field store opcode.
3529   // This forces the membar to follow the store.  (Bug 6500685 broke this.)
3530   // All the other membars (for other volatile slices, including AliasIdxBot,
3531   // which stands for all unknown volatile slices) are control-dependent
3532   // on the first membar.  This prevents later volatile loads or stores
3533   // from sliding up past the just-emitted store.
3534 
3535   MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3536   mb->set_req(TypeFunc::Control,control());
3537   if (alias_idx == Compile::AliasIdxBot) {
3538     mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3539   } else {
3540     assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3541     mb->set_req(TypeFunc::Memory, memory(alias_idx));
3542   }
3543   Node* membar = _gvn.transform(mb);
3544   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3545   if (alias_idx == Compile::AliasIdxBot) {
3546     merged_memory()->set_base_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)));
3547   } else {
3548     set_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)),alias_idx);
3549   }
3550   return membar;
3551 }
3552 
3553 //------------------------------shared_lock------------------------------------
3554 // Emit locking code.
3555 FastLockNode* GraphKit::shared_lock(Node* obj) {
3556   // bci is either a monitorenter bc or InvocationEntryBci
3557   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3558   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3559 
3560   if( !GenerateSynchronizationCode )
3561     return nullptr;                // Not locking things?
3562   if (stopped())                // Dead monitor?
3563     return nullptr;
3564 
3565   assert(dead_locals_are_killed(), "should kill locals before sync. point");
3566 
3567   // Box the stack location
3568   Node* box = new BoxLockNode(next_monitor());
3569   // Check for bailout after new BoxLockNode
3570   if (failing()) { return nullptr; }
3571   box = _gvn.transform(box);
3572   Node* mem = reset_memory();
3573 
3574   FastLockNode * flock = _gvn.transform(new FastLockNode(nullptr, obj, box) )->as_FastLock();
3575 
3576   // Add monitor to debug info for the slow path.  If we block inside the
3577   // slow path and de-opt, we need the monitor hanging around
3578   map()->push_monitor( flock );
3579 
3580   const TypeFunc *tf = LockNode::lock_type();
3581   LockNode *lock = new LockNode(C, tf);
3582 
3583   lock->init_req( TypeFunc::Control, control() );
3584   lock->init_req( TypeFunc::Memory , mem );
3585   lock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
3586   lock->init_req( TypeFunc::FramePtr, frameptr() );
3587   lock->init_req( TypeFunc::ReturnAdr, top() );
3588 
3589   lock->init_req(TypeFunc::Parms + 0, obj);
3590   lock->init_req(TypeFunc::Parms + 1, box);
3591   lock->init_req(TypeFunc::Parms + 2, flock);
3592   add_safepoint_edges(lock);
3593 
3594   lock = _gvn.transform( lock )->as_Lock();
3595 
3596   // lock has no side-effects, sets few values
3597   set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3598 
3599   insert_mem_bar(Op_MemBarAcquireLock);
3600 
3601   // Add this to the worklist so that the lock can be eliminated
3602   record_for_igvn(lock);
3603 
3604 #ifndef PRODUCT
3605   if (PrintLockStatistics) {
3606     // Update the counter for this lock.  Don't bother using an atomic
3607     // operation since we don't require absolute accuracy.
3608     lock->create_lock_counter(map()->jvms());
3609     increment_counter(lock->counter()->addr());
3610   }
3611 #endif
3612 
3613   return flock;
3614 }
3615 
3616 
3617 //------------------------------shared_unlock----------------------------------
3618 // Emit unlocking code.
3619 void GraphKit::shared_unlock(Node* box, Node* obj) {
3620   // bci is either a monitorenter bc or InvocationEntryBci
3621   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3622   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3623 
3624   if( !GenerateSynchronizationCode )
3625     return;
3626   if (stopped()) {               // Dead monitor?
3627     map()->pop_monitor();        // Kill monitor from debug info
3628     return;
3629   }
3630 
3631   // Memory barrier to avoid floating things down past the locked region
3632   insert_mem_bar(Op_MemBarReleaseLock);
3633 
3634   const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3635   UnlockNode *unlock = new UnlockNode(C, tf);
3636 #ifdef ASSERT
3637   unlock->set_dbg_jvms(sync_jvms());
3638 #endif
3639   uint raw_idx = Compile::AliasIdxRaw;
3640   unlock->init_req( TypeFunc::Control, control() );
3641   unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3642   unlock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
3643   unlock->init_req( TypeFunc::FramePtr, frameptr() );
3644   unlock->init_req( TypeFunc::ReturnAdr, top() );
3645 
3646   unlock->init_req(TypeFunc::Parms + 0, obj);
3647   unlock->init_req(TypeFunc::Parms + 1, box);
3648   unlock = _gvn.transform(unlock)->as_Unlock();
3649 
3650   Node* mem = reset_memory();
3651 
3652   // unlock has no side-effects, sets few values
3653   set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3654 
3655   // Kill monitor from debug info
3656   map()->pop_monitor( );
3657 }
3658 
3659 //-------------------------------get_layout_helper-----------------------------
3660 // If the given klass is a constant or known to be an array,
3661 // fetch the constant layout helper value into constant_value
3662 // and return null.  Otherwise, load the non-constant
3663 // layout helper value, and return the node which represents it.
3664 // This two-faced routine is useful because allocation sites
3665 // almost always feature constant types.
3666 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3667   const TypeKlassPtr* klass_t = _gvn.type(klass_node)->isa_klassptr();
3668   if (!StressReflectiveCode && klass_t != nullptr) {
3669     bool xklass = klass_t->klass_is_exact();
3670     if (xklass || (klass_t->isa_aryklassptr() && klass_t->is_aryklassptr()->elem() != Type::BOTTOM)) {
3671       jint lhelper;
3672       if (klass_t->isa_aryklassptr()) {
3673         BasicType elem = klass_t->as_instance_type()->isa_aryptr()->elem()->array_element_basic_type();
3674         if (is_reference_type(elem, true)) {
3675           elem = T_OBJECT;
3676         }
3677         lhelper = Klass::array_layout_helper(elem);
3678       } else {
3679         lhelper = klass_t->is_instklassptr()->exact_klass()->layout_helper();
3680       }
3681       if (lhelper != Klass::_lh_neutral_value) {
3682         constant_value = lhelper;
3683         return (Node*) nullptr;
3684       }
3685     }
3686   }
3687   constant_value = Klass::_lh_neutral_value;  // put in a known value
3688   Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
3689   return make_load(nullptr, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3690 }
3691 
3692 // We just put in an allocate/initialize with a big raw-memory effect.
3693 // Hook selected additional alias categories on the initialization.
3694 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3695                                 MergeMemNode* init_in_merge,
3696                                 Node* init_out_raw) {
3697   DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3698   assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3699 
3700   Node* prevmem = kit.memory(alias_idx);
3701   init_in_merge->set_memory_at(alias_idx, prevmem);
3702   kit.set_memory(init_out_raw, alias_idx);
3703 }
3704 
3705 //---------------------------set_output_for_allocation-------------------------
3706 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3707                                           const TypeOopPtr* oop_type,
3708                                           bool deoptimize_on_exception) {
3709   int rawidx = Compile::AliasIdxRaw;
3710   alloc->set_req( TypeFunc::FramePtr, frameptr() );
3711   add_safepoint_edges(alloc);
3712   Node* allocx = _gvn.transform(alloc);
3713   set_control( _gvn.transform(new ProjNode(allocx, TypeFunc::Control) ) );
3714   // create memory projection for i_o
3715   set_memory ( _gvn.transform( new ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3716   make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception);
3717 
3718   // create a memory projection as for the normal control path
3719   Node* malloc = _gvn.transform(new ProjNode(allocx, TypeFunc::Memory));
3720   set_memory(malloc, rawidx);
3721 
3722   // a normal slow-call doesn't change i_o, but an allocation does
3723   // we create a separate i_o projection for the normal control path
3724   set_i_o(_gvn.transform( new ProjNode(allocx, TypeFunc::I_O, false) ) );
3725   Node* rawoop = _gvn.transform( new ProjNode(allocx, TypeFunc::Parms) );
3726 
3727   // put in an initialization barrier
3728   InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3729                                                  rawoop)->as_Initialize();
3730   assert(alloc->initialization() == init,  "2-way macro link must work");
3731   assert(init ->allocation()     == alloc, "2-way macro link must work");
3732   {
3733     // Extract memory strands which may participate in the new object's
3734     // initialization, and source them from the new InitializeNode.
3735     // This will allow us to observe initializations when they occur,
3736     // and link them properly (as a group) to the InitializeNode.
3737     assert(init->in(InitializeNode::Memory) == malloc, "");
3738     MergeMemNode* minit_in = MergeMemNode::make(malloc);
3739     init->set_req(InitializeNode::Memory, minit_in);
3740     record_for_igvn(minit_in); // fold it up later, if possible
3741     Node* minit_out = memory(rawidx);
3742     assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3743     // Add an edge in the MergeMem for the header fields so an access
3744     // to one of those has correct memory state
3745     set_memory(minit_out, C->get_alias_index(oop_type->add_offset(oopDesc::mark_offset_in_bytes())));
3746     set_memory(minit_out, C->get_alias_index(oop_type->add_offset(oopDesc::klass_offset_in_bytes())));
3747     if (oop_type->isa_aryptr()) {
3748       const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3749       int            elemidx  = C->get_alias_index(telemref);
3750       hook_memory_on_init(*this, elemidx, minit_in, minit_out);
3751     } else if (oop_type->isa_instptr()) {
3752       ciInstanceKlass* ik = oop_type->is_instptr()->instance_klass();
3753       for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3754         ciField* field = ik->nonstatic_field_at(i);
3755         if (field->offset_in_bytes() >= TrackedInitializationLimit * HeapWordSize)
3756           continue;  // do not bother to track really large numbers of fields
3757         // Find (or create) the alias category for this field:
3758         int fieldidx = C->alias_type(field)->index();
3759         hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3760       }
3761     }
3762   }
3763 
3764   // Cast raw oop to the real thing...
3765   Node* javaoop = new CheckCastPPNode(control(), rawoop, oop_type);
3766   javaoop = _gvn.transform(javaoop);
3767   C->set_recent_alloc(control(), javaoop);
3768   assert(just_allocated_object(control()) == javaoop, "just allocated");
3769 
3770 #ifdef ASSERT
3771   { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3772     assert(AllocateNode::Ideal_allocation(rawoop) == alloc,
3773            "Ideal_allocation works");
3774     assert(AllocateNode::Ideal_allocation(javaoop) == alloc,
3775            "Ideal_allocation works");
3776     if (alloc->is_AllocateArray()) {
3777       assert(AllocateArrayNode::Ideal_array_allocation(rawoop) == alloc->as_AllocateArray(),
3778              "Ideal_allocation works");
3779       assert(AllocateArrayNode::Ideal_array_allocation(javaoop) == alloc->as_AllocateArray(),
3780              "Ideal_allocation works");
3781     } else {
3782       assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3783     }
3784   }
3785 #endif //ASSERT
3786 
3787   return javaoop;
3788 }
3789 
3790 //---------------------------new_instance--------------------------------------
3791 // This routine takes a klass_node which may be constant (for a static type)
3792 // or may be non-constant (for reflective code).  It will work equally well
3793 // for either, and the graph will fold nicely if the optimizer later reduces
3794 // the type to a constant.
3795 // The optional arguments are for specialized use by intrinsics:
3796 //  - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3797 //  - If 'return_size_val', report the total object size to the caller.
3798 //  - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3799 Node* GraphKit::new_instance(Node* klass_node,
3800                              Node* extra_slow_test,
3801                              Node* *return_size_val,
3802                              bool deoptimize_on_exception) {
3803   // Compute size in doublewords
3804   // The size is always an integral number of doublewords, represented
3805   // as a positive bytewise size stored in the klass's layout_helper.
3806   // The layout_helper also encodes (in a low bit) the need for a slow path.
3807   jint  layout_con = Klass::_lh_neutral_value;
3808   Node* layout_val = get_layout_helper(klass_node, layout_con);
3809   int   layout_is_con = (layout_val == nullptr);
3810 
3811   if (extra_slow_test == nullptr)  extra_slow_test = intcon(0);
3812   // Generate the initial go-slow test.  It's either ALWAYS (return a
3813   // Node for 1) or NEVER (return a null) or perhaps (in the reflective
3814   // case) a computed value derived from the layout_helper.
3815   Node* initial_slow_test = nullptr;
3816   if (layout_is_con) {
3817     assert(!StressReflectiveCode, "stress mode does not use these paths");
3818     bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3819     initial_slow_test = must_go_slow ? intcon(1) : extra_slow_test;
3820   } else {   // reflective case
3821     // This reflective path is used by Unsafe.allocateInstance.
3822     // (It may be stress-tested by specifying StressReflectiveCode.)
3823     // Basically, we want to get into the VM is there's an illegal argument.
3824     Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3825     initial_slow_test = _gvn.transform( new AndINode(layout_val, bit) );
3826     if (extra_slow_test != intcon(0)) {
3827       initial_slow_test = _gvn.transform( new OrINode(initial_slow_test, extra_slow_test) );
3828     }
3829     // (Macro-expander will further convert this to a Bool, if necessary.)
3830   }
3831 
3832   // Find the size in bytes.  This is easy; it's the layout_helper.
3833   // The size value must be valid even if the slow path is taken.
3834   Node* size = nullptr;
3835   if (layout_is_con) {
3836     size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3837   } else {   // reflective case
3838     // This reflective path is used by clone and Unsafe.allocateInstance.
3839     size = ConvI2X(layout_val);
3840 
3841     // Clear the low bits to extract layout_helper_size_in_bytes:
3842     assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3843     Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3844     size = _gvn.transform( new AndXNode(size, mask) );
3845   }
3846   if (return_size_val != nullptr) {
3847     (*return_size_val) = size;
3848   }
3849 
3850   // This is a precise notnull oop of the klass.
3851   // (Actually, it need not be precise if this is a reflective allocation.)
3852   // It's what we cast the result to.
3853   const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3854   if (!tklass)  tklass = TypeInstKlassPtr::OBJECT;
3855   const TypeOopPtr* oop_type = tklass->as_instance_type();
3856 
3857   // Now generate allocation code
3858 
3859   // The entire memory state is needed for slow path of the allocation
3860   // since GC and deoptimization can happened.
3861   Node *mem = reset_memory();
3862   set_all_memory(mem); // Create new memory state
3863 
3864   AllocateNode* alloc = new AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3865                                          control(), mem, i_o(),
3866                                          size, klass_node,
3867                                          initial_slow_test);
3868 
3869   return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception);
3870 }
3871 
3872 //-------------------------------new_array-------------------------------------
3873 // helper for both newarray and anewarray
3874 // The 'length' parameter is (obviously) the length of the array.
3875 // The optional arguments are for specialized use by intrinsics:
3876 //  - If 'return_size_val', report the non-padded array size (sum of header size
3877 //    and array body) to the caller.
3878 //  - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3879 Node* GraphKit::new_array(Node* klass_node,     // array klass (maybe variable)
3880                           Node* length,         // number of array elements
3881                           int   nargs,          // number of arguments to push back for uncommon trap
3882                           Node* *return_size_val,
3883                           bool deoptimize_on_exception) {
3884   jint  layout_con = Klass::_lh_neutral_value;
3885   Node* layout_val = get_layout_helper(klass_node, layout_con);
3886   int   layout_is_con = (layout_val == nullptr);
3887 
3888   if (!layout_is_con && !StressReflectiveCode &&
3889       !too_many_traps(Deoptimization::Reason_class_check)) {
3890     // This is a reflective array creation site.
3891     // Optimistically assume that it is a subtype of Object[],
3892     // so that we can fold up all the address arithmetic.
3893     layout_con = Klass::array_layout_helper(T_OBJECT);
3894     Node* cmp_lh = _gvn.transform( new CmpINode(layout_val, intcon(layout_con)) );
3895     Node* bol_lh = _gvn.transform( new BoolNode(cmp_lh, BoolTest::eq) );
3896     { BuildCutout unless(this, bol_lh, PROB_MAX);
3897       inc_sp(nargs);
3898       uncommon_trap(Deoptimization::Reason_class_check,
3899                     Deoptimization::Action_maybe_recompile);
3900     }
3901     layout_val = nullptr;
3902     layout_is_con = true;
3903   }
3904 
3905   // Generate the initial go-slow test.  Make sure we do not overflow
3906   // if length is huge (near 2Gig) or negative!  We do not need
3907   // exact double-words here, just a close approximation of needed
3908   // double-words.  We can't add any offset or rounding bits, lest we
3909   // take a size -1 of bytes and make it positive.  Use an unsigned
3910   // compare, so negative sizes look hugely positive.
3911   int fast_size_limit = FastAllocateSizeLimit;
3912   if (layout_is_con) {
3913     assert(!StressReflectiveCode, "stress mode does not use these paths");
3914     // Increase the size limit if we have exact knowledge of array type.
3915     int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3916     fast_size_limit <<= (LogBytesPerLong - log2_esize);
3917   }
3918 
3919   Node* initial_slow_cmp  = _gvn.transform( new CmpUNode( length, intcon( fast_size_limit ) ) );
3920   Node* initial_slow_test = _gvn.transform( new BoolNode( initial_slow_cmp, BoolTest::gt ) );
3921 
3922   // --- Size Computation ---
3923   // array_size = round_to_heap(array_header + (length << elem_shift));
3924   // where round_to_heap(x) == align_to(x, MinObjAlignmentInBytes)
3925   // and align_to(x, y) == ((x + y-1) & ~(y-1))
3926   // The rounding mask is strength-reduced, if possible.
3927   int round_mask = MinObjAlignmentInBytes - 1;
3928   Node* header_size = nullptr;
3929   // (T_BYTE has the weakest alignment and size restrictions...)
3930   if (layout_is_con) {
3931     int       hsize  = Klass::layout_helper_header_size(layout_con);
3932     int       eshift = Klass::layout_helper_log2_element_size(layout_con);
3933     if ((round_mask & ~right_n_bits(eshift)) == 0)
3934       round_mask = 0;  // strength-reduce it if it goes away completely
3935     assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3936     int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3937     assert(header_size_min <= hsize, "generic minimum is smallest");
3938     header_size = intcon(hsize);
3939   } else {
3940     Node* hss   = intcon(Klass::_lh_header_size_shift);
3941     Node* hsm   = intcon(Klass::_lh_header_size_mask);
3942     header_size = _gvn.transform(new URShiftINode(layout_val, hss));
3943     header_size = _gvn.transform(new AndINode(header_size, hsm));
3944   }
3945 
3946   Node* elem_shift = nullptr;
3947   if (layout_is_con) {
3948     int eshift = Klass::layout_helper_log2_element_size(layout_con);
3949     if (eshift != 0)
3950       elem_shift = intcon(eshift);
3951   } else {
3952     // There is no need to mask or shift this value.
3953     // The semantics of LShiftINode include an implicit mask to 0x1F.
3954     assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3955     elem_shift = layout_val;
3956   }
3957 
3958   // Transition to native address size for all offset calculations:
3959   Node* lengthx = ConvI2X(length);
3960   Node* headerx = ConvI2X(header_size);
3961 #ifdef _LP64
3962   { const TypeInt* tilen = _gvn.find_int_type(length);
3963     if (tilen != nullptr && tilen->_lo < 0) {
3964       // Add a manual constraint to a positive range.  Cf. array_element_address.
3965       jint size_max = fast_size_limit;
3966       if (size_max > tilen->_hi)  size_max = tilen->_hi;
3967       const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin);
3968 
3969       // Only do a narrow I2L conversion if the range check passed.
3970       IfNode* iff = new IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
3971       _gvn.transform(iff);
3972       RegionNode* region = new RegionNode(3);
3973       _gvn.set_type(region, Type::CONTROL);
3974       lengthx = new PhiNode(region, TypeLong::LONG);
3975       _gvn.set_type(lengthx, TypeLong::LONG);
3976 
3977       // Range check passed. Use ConvI2L node with narrow type.
3978       Node* passed = IfFalse(iff);
3979       region->init_req(1, passed);
3980       // Make I2L conversion control dependent to prevent it from
3981       // floating above the range check during loop optimizations.
3982       lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed));
3983 
3984       // Range check failed. Use ConvI2L with wide type because length may be invalid.
3985       region->init_req(2, IfTrue(iff));
3986       lengthx->init_req(2, ConvI2X(length));
3987 
3988       set_control(region);
3989       record_for_igvn(region);
3990       record_for_igvn(lengthx);
3991     }
3992   }
3993 #endif
3994 
3995   // Combine header size and body size for the array copy part, then align (if
3996   // necessary) for the allocation part. This computation cannot overflow,
3997   // because it is used only in two places, one where the length is sharply
3998   // limited, and the other after a successful allocation.
3999   Node* abody = lengthx;
4000   if (elem_shift != nullptr) {
4001     abody = _gvn.transform(new LShiftXNode(lengthx, elem_shift));
4002   }
4003   Node* non_rounded_size = _gvn.transform(new AddXNode(headerx, abody));
4004 
4005   if (return_size_val != nullptr) {
4006     // This is the size
4007     (*return_size_val) = non_rounded_size;
4008   }
4009 
4010   Node* size = non_rounded_size;
4011   if (round_mask != 0) {
4012     Node* mask1 = MakeConX(round_mask);
4013     size = _gvn.transform(new AddXNode(size, mask1));
4014     Node* mask2 = MakeConX(~round_mask);
4015     size = _gvn.transform(new AndXNode(size, mask2));
4016   }
4017   // else if round_mask == 0, the size computation is self-rounding
4018 
4019   // Now generate allocation code
4020 
4021   // The entire memory state is needed for slow path of the allocation
4022   // since GC and deoptimization can happened.
4023   Node *mem = reset_memory();
4024   set_all_memory(mem); // Create new memory state
4025 
4026   if (initial_slow_test->is_Bool()) {
4027     // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
4028     initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
4029   }
4030 
4031   const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
4032   Node* valid_length_test = _gvn.intcon(1);
4033   if (ary_type->isa_aryptr()) {
4034     BasicType bt = ary_type->isa_aryptr()->elem()->array_element_basic_type();
4035     jint max = TypeAryPtr::max_array_length(bt);
4036     Node* valid_length_cmp  = _gvn.transform(new CmpUNode(length, intcon(max)));
4037     valid_length_test = _gvn.transform(new BoolNode(valid_length_cmp, BoolTest::le));
4038   }
4039 
4040   // Create the AllocateArrayNode and its result projections
4041   AllocateArrayNode* alloc
4042     = new AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
4043                             control(), mem, i_o(),
4044                             size, klass_node,
4045                             initial_slow_test,
4046                             length, valid_length_test);
4047 
4048   // Cast to correct type.  Note that the klass_node may be constant or not,
4049   // and in the latter case the actual array type will be inexact also.
4050   // (This happens via a non-constant argument to inline_native_newArray.)
4051   // In any case, the value of klass_node provides the desired array type.
4052   const TypeInt* length_type = _gvn.find_int_type(length);
4053   if (ary_type->isa_aryptr() && length_type != nullptr) {
4054     // Try to get a better type than POS for the size
4055     ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
4056   }
4057 
4058   Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception);
4059 
4060   array_ideal_length(alloc, ary_type, true);
4061   return javaoop;
4062 }
4063 
4064 // The following "Ideal_foo" functions are placed here because they recognize
4065 // the graph shapes created by the functions immediately above.
4066 
4067 //---------------------------Ideal_allocation----------------------------------
4068 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
4069 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr) {
4070   if (ptr == nullptr) {     // reduce dumb test in callers
4071     return nullptr;
4072   }
4073 
4074   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
4075   ptr = bs->step_over_gc_barrier(ptr);
4076 
4077   if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
4078     ptr = ptr->in(1);
4079     if (ptr == nullptr) return nullptr;
4080   }
4081   // Return null for allocations with several casts:
4082   //   j.l.reflect.Array.newInstance(jobject, jint)
4083   //   Object.clone()
4084   // to keep more precise type from last cast.
4085   if (ptr->is_Proj()) {
4086     Node* allo = ptr->in(0);
4087     if (allo != nullptr && allo->is_Allocate()) {
4088       return allo->as_Allocate();
4089     }
4090   }
4091   // Report failure to match.
4092   return nullptr;
4093 }
4094 
4095 // Fancy version which also strips off an offset (and reports it to caller).
4096 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseValues* phase,
4097                                              intptr_t& offset) {
4098   Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
4099   if (base == nullptr)  return nullptr;
4100   return Ideal_allocation(base);
4101 }
4102 
4103 // Trace Initialize <- Proj[Parm] <- Allocate
4104 AllocateNode* InitializeNode::allocation() {
4105   Node* rawoop = in(InitializeNode::RawAddress);
4106   if (rawoop->is_Proj()) {
4107     Node* alloc = rawoop->in(0);
4108     if (alloc->is_Allocate()) {
4109       return alloc->as_Allocate();
4110     }
4111   }
4112   return nullptr;
4113 }
4114 
4115 // Trace Allocate -> Proj[Parm] -> Initialize
4116 InitializeNode* AllocateNode::initialization() {
4117   ProjNode* rawoop = proj_out_or_null(AllocateNode::RawAddress);
4118   if (rawoop == nullptr)  return nullptr;
4119   for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
4120     Node* init = rawoop->fast_out(i);
4121     if (init->is_Initialize()) {
4122       assert(init->as_Initialize()->allocation() == this, "2-way link");
4123       return init->as_Initialize();
4124     }
4125   }
4126   return nullptr;
4127 }
4128 
4129 // Add a Parse Predicate with an uncommon trap on the failing/false path. Normal control will continue on the true path.
4130 void GraphKit::add_parse_predicate(Deoptimization::DeoptReason reason, const int nargs) {
4131   // Too many traps seen?
4132   if (too_many_traps(reason)) {
4133 #ifdef ASSERT
4134     if (TraceLoopPredicate) {
4135       int tc = C->trap_count(reason);
4136       tty->print("too many traps=%s tcount=%d in ",
4137                     Deoptimization::trap_reason_name(reason), tc);
4138       method()->print(); // which method has too many predicate traps
4139       tty->cr();
4140     }
4141 #endif
4142     // We cannot afford to take more traps here,
4143     // do not generate Parse Predicate.
4144     return;
4145   }
4146 
4147   ParsePredicateNode* parse_predicate = new ParsePredicateNode(control(), reason, &_gvn);
4148   _gvn.set_type(parse_predicate, parse_predicate->Value(&_gvn));
4149   Node* if_false = _gvn.transform(new IfFalseNode(parse_predicate));
4150   {
4151     PreserveJVMState pjvms(this);
4152     set_control(if_false);
4153     inc_sp(nargs);
4154     uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
4155   }
4156   Node* if_true = _gvn.transform(new IfTrueNode(parse_predicate));
4157   set_control(if_true);
4158 }
4159 
4160 // Add Parse Predicates which serve as placeholders to create new Runtime Predicates above them. All
4161 // Runtime Predicates inside a Runtime Predicate block share the same uncommon trap as the Parse Predicate.
4162 void GraphKit::add_parse_predicates(int nargs) {
4163   if (UseLoopPredicate) {
4164     add_parse_predicate(Deoptimization::Reason_predicate, nargs);
4165   }
4166   if (UseProfiledLoopPredicate) {
4167     add_parse_predicate(Deoptimization::Reason_profile_predicate, nargs);
4168   }
4169   // Loop Limit Check Predicate should be near the loop.
4170   add_parse_predicate(Deoptimization::Reason_loop_limit_check, nargs);
4171 }
4172 
4173 void GraphKit::sync_kit(IdealKit& ideal) {
4174   set_all_memory(ideal.merged_memory());
4175   set_i_o(ideal.i_o());
4176   set_control(ideal.ctrl());
4177 }
4178 
4179 void GraphKit::final_sync(IdealKit& ideal) {
4180   // Final sync IdealKit and graphKit.
4181   sync_kit(ideal);
4182 }
4183 
4184 Node* GraphKit::load_String_length(Node* str, bool set_ctrl) {
4185   Node* len = load_array_length(load_String_value(str, set_ctrl));
4186   Node* coder = load_String_coder(str, set_ctrl);
4187   // Divide length by 2 if coder is UTF16
4188   return _gvn.transform(new RShiftINode(len, coder));
4189 }
4190 
4191 Node* GraphKit::load_String_value(Node* str, bool set_ctrl) {
4192   int value_offset = java_lang_String::value_offset();
4193   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4194                                                      false, nullptr, 0);
4195   const TypePtr* value_field_type = string_type->add_offset(value_offset);
4196   const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
4197                                                   TypeAry::make(TypeInt::BYTE, TypeInt::POS),
4198                                                   ciTypeArrayKlass::make(T_BYTE), true, 0);
4199   Node* p = basic_plus_adr(str, str, value_offset);
4200   Node* load = access_load_at(str, p, value_field_type, value_type, T_OBJECT,
4201                               IN_HEAP | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0) | MO_UNORDERED);
4202   return load;
4203 }
4204 
4205 Node* GraphKit::load_String_coder(Node* str, bool set_ctrl) {
4206   if (!CompactStrings) {
4207     return intcon(java_lang_String::CODER_UTF16);
4208   }
4209   int coder_offset = java_lang_String::coder_offset();
4210   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4211                                                      false, nullptr, 0);
4212   const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4213 
4214   Node* p = basic_plus_adr(str, str, coder_offset);
4215   Node* load = access_load_at(str, p, coder_field_type, TypeInt::BYTE, T_BYTE,
4216                               IN_HEAP | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0) | MO_UNORDERED);
4217   return load;
4218 }
4219 
4220 void GraphKit::store_String_value(Node* str, Node* value) {
4221   int value_offset = java_lang_String::value_offset();
4222   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4223                                                      false, nullptr, 0);
4224   const TypePtr* value_field_type = string_type->add_offset(value_offset);
4225 
4226   access_store_at(str,  basic_plus_adr(str, value_offset), value_field_type,
4227                   value, TypeAryPtr::BYTES, T_OBJECT, IN_HEAP | MO_UNORDERED);
4228 }
4229 
4230 void GraphKit::store_String_coder(Node* str, Node* value) {
4231   int coder_offset = java_lang_String::coder_offset();
4232   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4233                                                      false, nullptr, 0);
4234   const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4235 
4236   access_store_at(str, basic_plus_adr(str, coder_offset), coder_field_type,
4237                   value, TypeInt::BYTE, T_BYTE, IN_HEAP | MO_UNORDERED);
4238 }
4239 
4240 // Capture src and dst memory state with a MergeMemNode
4241 Node* GraphKit::capture_memory(const TypePtr* src_type, const TypePtr* dst_type) {
4242   if (src_type == dst_type) {
4243     // Types are equal, we don't need a MergeMemNode
4244     return memory(src_type);
4245   }
4246   MergeMemNode* merge = MergeMemNode::make(map()->memory());
4247   record_for_igvn(merge); // fold it up later, if possible
4248   int src_idx = C->get_alias_index(src_type);
4249   int dst_idx = C->get_alias_index(dst_type);
4250   merge->set_memory_at(src_idx, memory(src_idx));
4251   merge->set_memory_at(dst_idx, memory(dst_idx));
4252   return merge;
4253 }
4254 
4255 Node* GraphKit::compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count) {
4256   assert(Matcher::match_rule_supported(Op_StrCompressedCopy), "Intrinsic not supported");
4257   assert(src_type == TypeAryPtr::BYTES || src_type == TypeAryPtr::CHARS, "invalid source type");
4258   // If input and output memory types differ, capture both states to preserve
4259   // the dependency between preceding and subsequent loads/stores.
4260   // For example, the following program:
4261   //  StoreB
4262   //  compress_string
4263   //  LoadB
4264   // has this memory graph (use->def):
4265   //  LoadB -> compress_string -> CharMem
4266   //             ... -> StoreB -> ByteMem
4267   // The intrinsic hides the dependency between LoadB and StoreB, causing
4268   // the load to read from memory not containing the result of the StoreB.
4269   // The correct memory graph should look like this:
4270   //  LoadB -> compress_string -> MergeMem(CharMem, StoreB(ByteMem))
4271   Node* mem = capture_memory(src_type, TypeAryPtr::BYTES);
4272   StrCompressedCopyNode* str = new StrCompressedCopyNode(control(), mem, src, dst, count);
4273   Node* res_mem = _gvn.transform(new SCMemProjNode(_gvn.transform(str)));
4274   set_memory(res_mem, TypeAryPtr::BYTES);
4275   return str;
4276 }
4277 
4278 void GraphKit::inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count) {
4279   assert(Matcher::match_rule_supported(Op_StrInflatedCopy), "Intrinsic not supported");
4280   assert(dst_type == TypeAryPtr::BYTES || dst_type == TypeAryPtr::CHARS, "invalid dest type");
4281   // Capture src and dst memory (see comment in 'compress_string').
4282   Node* mem = capture_memory(TypeAryPtr::BYTES, dst_type);
4283   StrInflatedCopyNode* str = new StrInflatedCopyNode(control(), mem, src, dst, count);
4284   set_memory(_gvn.transform(str), dst_type);
4285 }
4286 
4287 void GraphKit::inflate_string_slow(Node* src, Node* dst, Node* start, Node* count) {
4288   /**
4289    * int i_char = start;
4290    * for (int i_byte = 0; i_byte < count; i_byte++) {
4291    *   dst[i_char++] = (char)(src[i_byte] & 0xff);
4292    * }
4293    */
4294   add_parse_predicates();
4295   C->set_has_loops(true);
4296 
4297   RegionNode* head = new RegionNode(3);
4298   head->init_req(1, control());
4299   gvn().set_type(head, Type::CONTROL);
4300   record_for_igvn(head);
4301 
4302   Node* i_byte = new PhiNode(head, TypeInt::INT);
4303   i_byte->init_req(1, intcon(0));
4304   gvn().set_type(i_byte, TypeInt::INT);
4305   record_for_igvn(i_byte);
4306 
4307   Node* i_char = new PhiNode(head, TypeInt::INT);
4308   i_char->init_req(1, start);
4309   gvn().set_type(i_char, TypeInt::INT);
4310   record_for_igvn(i_char);
4311 
4312   Node* mem = PhiNode::make(head, memory(TypeAryPtr::BYTES), Type::MEMORY, TypeAryPtr::BYTES);
4313   gvn().set_type(mem, Type::MEMORY);
4314   record_for_igvn(mem);
4315   set_control(head);
4316   set_memory(mem, TypeAryPtr::BYTES);
4317   Node* ch = load_array_element(src, i_byte, TypeAryPtr::BYTES, /* set_ctrl */ true);
4318   Node* st = store_to_memory(control(), array_element_address(dst, i_char, T_BYTE),
4319                              AndI(ch, intcon(0xff)), T_CHAR, TypeAryPtr::BYTES, MemNode::unordered,
4320                              false, false, true /* mismatched */);
4321 
4322   IfNode* iff = create_and_map_if(head, Bool(CmpI(i_byte, count), BoolTest::lt), PROB_FAIR, COUNT_UNKNOWN);
4323   head->init_req(2, IfTrue(iff));
4324   mem->init_req(2, st);
4325   i_byte->init_req(2, AddI(i_byte, intcon(1)));
4326   i_char->init_req(2, AddI(i_char, intcon(2)));
4327 
4328   set_control(IfFalse(iff));
4329   set_memory(st, TypeAryPtr::BYTES);
4330 }
4331 
4332 Node* GraphKit::make_constant_from_field(ciField* field, Node* obj) {
4333   if (!field->is_constant()) {
4334     return nullptr; // Field not marked as constant.
4335   }
4336   ciInstance* holder = nullptr;
4337   if (!field->is_static()) {
4338     ciObject* const_oop = obj->bottom_type()->is_oopptr()->const_oop();
4339     if (const_oop != nullptr && const_oop->is_instance()) {
4340       holder = const_oop->as_instance();
4341     }
4342   }
4343   const Type* con_type = Type::make_constant_from_field(field, holder, field->layout_type(),
4344                                                         /*is_unsigned_load=*/false);
4345   if (con_type != nullptr) {
4346     return makecon(con_type);
4347   }
4348   return nullptr;
4349 }
4350 
4351 Node* GraphKit::maybe_narrow_object_type(Node* obj, ciKlass* type) {
4352   const TypeOopPtr* obj_type = obj->bottom_type()->isa_oopptr();
4353   const TypeOopPtr* sig_type = TypeOopPtr::make_from_klass(type);
4354   if (obj_type != nullptr && sig_type->is_loaded() && !obj_type->higher_equal(sig_type)) {
4355     const Type* narrow_obj_type = obj_type->filter_speculative(sig_type); // keep speculative part
4356     Node* casted_obj = gvn().transform(new CheckCastPPNode(control(), obj, narrow_obj_type));
4357     return casted_obj;
4358   }
4359   return obj;
4360 }