1 /*
   2  * Copyright (c) 2001, 2025, 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 "ci/ciUtilities.hpp"
  26 #include "classfile/javaClasses.hpp"
  27 #include "ci/ciObjArray.hpp"
  28 #include "asm/register.hpp"
  29 #include "compiler/compileLog.hpp"
  30 #include "gc/shared/barrierSet.hpp"
  31 #include "gc/shared/c2/barrierSetC2.hpp"
  32 #include "interpreter/interpreter.hpp"
  33 #include "memory/resourceArea.hpp"
  34 #include "opto/addnode.hpp"
  35 #include "opto/castnode.hpp"
  36 #include "opto/convertnode.hpp"
  37 #include "opto/graphKit.hpp"
  38 #include "opto/idealKit.hpp"
  39 #include "opto/intrinsicnode.hpp"
  40 #include "opto/locknode.hpp"
  41 #include "opto/machnode.hpp"
  42 #include "opto/opaquenode.hpp"
  43 #include "opto/parse.hpp"
  44 #include "opto/rootnode.hpp"
  45 #include "opto/runtime.hpp"
  46 #include "opto/subtypenode.hpp"
  47 #include "runtime/deoptimization.hpp"
  48 #include "runtime/sharedRuntime.hpp"
  49 #include "utilities/bitMap.inline.hpp"
  50 #include "utilities/powerOfTwo.hpp"
  51 #include "utilities/growableArray.hpp"
  52 
  53 //----------------------------GraphKit-----------------------------------------
  54 // Main utility constructor.
  55 GraphKit::GraphKit(JVMState* jvms)
  56   : Phase(Phase::Parser),
  57     _env(C->env()),
  58     _gvn(*C->initial_gvn()),
  59     _barrier_set(BarrierSet::barrier_set()->barrier_set_c2())
  60 {
  61   _exceptions = jvms->map()->next_exception();
  62   if (_exceptions != nullptr)  jvms->map()->set_next_exception(nullptr);
  63   set_jvms(jvms);
  64 }
  65 
  66 // Private constructor for parser.
  67 GraphKit::GraphKit()
  68   : Phase(Phase::Parser),
  69     _env(C->env()),
  70     _gvn(*C->initial_gvn()),
  71     _barrier_set(BarrierSet::barrier_set()->barrier_set_c2())
  72 {
  73   _exceptions = nullptr;
  74   set_map(nullptr);
  75   debug_only(_sp = -99);
  76   debug_only(set_bci(-99));
  77 }
  78 
  79 
  80 
  81 //---------------------------clean_stack---------------------------------------
  82 // Clear away rubbish from the stack area of the JVM state.
  83 // This destroys any arguments that may be waiting on the stack.
  84 void GraphKit::clean_stack(int from_sp) {
  85   SafePointNode* map      = this->map();
  86   JVMState*      jvms     = this->jvms();
  87   int            stk_size = jvms->stk_size();
  88   int            stkoff   = jvms->stkoff();
  89   Node*          top      = this->top();
  90   for (int i = from_sp; i < stk_size; i++) {
  91     if (map->in(stkoff + i) != top) {
  92       map->set_req(stkoff + i, top);
  93     }
  94   }
  95 }
  96 
  97 
  98 //--------------------------------sync_jvms-----------------------------------
  99 // Make sure our current jvms agrees with our parse state.
 100 JVMState* GraphKit::sync_jvms() const {
 101   JVMState* jvms = this->jvms();
 102   jvms->set_bci(bci());       // Record the new bci in the JVMState
 103   jvms->set_sp(sp());         // Record the new sp in the JVMState
 104   assert(jvms_in_sync(), "jvms is now in sync");
 105   return jvms;
 106 }
 107 
 108 //--------------------------------sync_jvms_for_reexecute---------------------
 109 // Make sure our current jvms agrees with our parse state.  This version
 110 // uses the reexecute_sp for reexecuting bytecodes.
 111 JVMState* GraphKit::sync_jvms_for_reexecute() {
 112   JVMState* jvms = this->jvms();
 113   jvms->set_bci(bci());          // Record the new bci in the JVMState
 114   jvms->set_sp(reexecute_sp());  // Record the new sp in the JVMState
 115   return jvms;
 116 }
 117 
 118 #ifdef ASSERT
 119 bool GraphKit::jvms_in_sync() const {
 120   Parse* parse = is_Parse();
 121   if (parse == nullptr) {
 122     if (bci() !=      jvms()->bci())          return false;
 123     if (sp()  != (int)jvms()->sp())           return false;
 124     return true;
 125   }
 126   if (jvms()->method() != parse->method())    return false;
 127   if (jvms()->bci()    != parse->bci())       return false;
 128   int jvms_sp = jvms()->sp();
 129   if (jvms_sp          != parse->sp())        return false;
 130   int jvms_depth = jvms()->depth();
 131   if (jvms_depth       != parse->depth())     return false;
 132   return true;
 133 }
 134 
 135 // Local helper checks for special internal merge points
 136 // used to accumulate and merge exception states.
 137 // They are marked by the region's in(0) edge being the map itself.
 138 // Such merge points must never "escape" into the parser at large,
 139 // until they have been handed to gvn.transform.
 140 static bool is_hidden_merge(Node* reg) {
 141   if (reg == nullptr)  return false;
 142   if (reg->is_Phi()) {
 143     reg = reg->in(0);
 144     if (reg == nullptr)  return false;
 145   }
 146   return reg->is_Region() && reg->in(0) != nullptr && reg->in(0)->is_Root();
 147 }
 148 
 149 void GraphKit::verify_map() const {
 150   if (map() == nullptr)  return;  // null map is OK
 151   assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
 152   assert(!map()->has_exceptions(),    "call add_exception_states_from 1st");
 153   assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
 154 }
 155 
 156 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
 157   assert(ex_map->next_exception() == nullptr, "not already part of a chain");
 158   assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
 159 }
 160 #endif
 161 
 162 //---------------------------stop_and_kill_map---------------------------------
 163 // Set _map to null, signalling a stop to further bytecode execution.
 164 // First smash the current map's control to a constant, to mark it dead.
 165 void GraphKit::stop_and_kill_map() {
 166   SafePointNode* dead_map = stop();
 167   if (dead_map != nullptr) {
 168     dead_map->disconnect_inputs(C); // Mark the map as killed.
 169     assert(dead_map->is_killed(), "must be so marked");
 170   }
 171 }
 172 
 173 
 174 //--------------------------------stopped--------------------------------------
 175 // Tell if _map is null, or control is top.
 176 bool GraphKit::stopped() {
 177   if (map() == nullptr)        return true;
 178   else if (control() == top()) return true;
 179   else                         return false;
 180 }
 181 
 182 
 183 //-----------------------------has_exception_handler----------------------------------
 184 // Tell if this method or any caller method has exception handlers.
 185 bool GraphKit::has_exception_handler() {
 186   for (JVMState* jvmsp = jvms(); jvmsp != nullptr; jvmsp = jvmsp->caller()) {
 187     if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
 188       return true;
 189     }
 190   }
 191   return false;
 192 }
 193 
 194 //------------------------------save_ex_oop------------------------------------
 195 // Save an exception without blowing stack contents or other JVM state.
 196 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
 197   assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
 198   ex_map->add_req(ex_oop);
 199   debug_only(verify_exception_state(ex_map));
 200 }
 201 
 202 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
 203   assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
 204   Node* ex_oop = ex_map->in(ex_map->req()-1);
 205   if (clear_it)  ex_map->del_req(ex_map->req()-1);
 206   return ex_oop;
 207 }
 208 
 209 //-----------------------------saved_ex_oop------------------------------------
 210 // Recover a saved exception from its map.
 211 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
 212   return common_saved_ex_oop(ex_map, false);
 213 }
 214 
 215 //--------------------------clear_saved_ex_oop---------------------------------
 216 // Erase a previously saved exception from its map.
 217 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
 218   return common_saved_ex_oop(ex_map, true);
 219 }
 220 
 221 #ifdef ASSERT
 222 //---------------------------has_saved_ex_oop----------------------------------
 223 // Erase a previously saved exception from its map.
 224 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
 225   return ex_map->req() == ex_map->jvms()->endoff()+1;
 226 }
 227 #endif
 228 
 229 //-------------------------make_exception_state--------------------------------
 230 // Turn the current JVM state into an exception state, appending the ex_oop.
 231 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
 232   sync_jvms();
 233   SafePointNode* ex_map = stop();  // do not manipulate this map any more
 234   set_saved_ex_oop(ex_map, ex_oop);
 235   return ex_map;
 236 }
 237 
 238 
 239 //--------------------------add_exception_state--------------------------------
 240 // Add an exception to my list of exceptions.
 241 void GraphKit::add_exception_state(SafePointNode* ex_map) {
 242   if (ex_map == nullptr || ex_map->control() == top()) {
 243     return;
 244   }
 245 #ifdef ASSERT
 246   verify_exception_state(ex_map);
 247   if (has_exceptions()) {
 248     assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
 249   }
 250 #endif
 251 
 252   // If there is already an exception of exactly this type, merge with it.
 253   // In particular, null-checks and other low-level exceptions common up here.
 254   Node*       ex_oop  = saved_ex_oop(ex_map);
 255   const Type* ex_type = _gvn.type(ex_oop);
 256   if (ex_oop == top()) {
 257     // No action needed.
 258     return;
 259   }
 260   assert(ex_type->isa_instptr(), "exception must be an instance");
 261   for (SafePointNode* e2 = _exceptions; e2 != nullptr; e2 = e2->next_exception()) {
 262     const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
 263     // We check sp also because call bytecodes can generate exceptions
 264     // both before and after arguments are popped!
 265     if (ex_type2 == ex_type
 266         && e2->_jvms->sp() == ex_map->_jvms->sp()) {
 267       combine_exception_states(ex_map, e2);
 268       return;
 269     }
 270   }
 271 
 272   // No pre-existing exception of the same type.  Chain it on the list.
 273   push_exception_state(ex_map);
 274 }
 275 
 276 //-----------------------add_exception_states_from-----------------------------
 277 void GraphKit::add_exception_states_from(JVMState* jvms) {
 278   SafePointNode* ex_map = jvms->map()->next_exception();
 279   if (ex_map != nullptr) {
 280     jvms->map()->set_next_exception(nullptr);
 281     for (SafePointNode* next_map; ex_map != nullptr; ex_map = next_map) {
 282       next_map = ex_map->next_exception();
 283       ex_map->set_next_exception(nullptr);
 284       add_exception_state(ex_map);
 285     }
 286   }
 287 }
 288 
 289 //-----------------------transfer_exceptions_into_jvms-------------------------
 290 JVMState* GraphKit::transfer_exceptions_into_jvms() {
 291   if (map() == nullptr) {
 292     // We need a JVMS to carry the exceptions, but the map has gone away.
 293     // Create a scratch JVMS, cloned from any of the exception states...
 294     if (has_exceptions()) {
 295       _map = _exceptions;
 296       _map = clone_map();
 297       _map->set_next_exception(nullptr);
 298       clear_saved_ex_oop(_map);
 299       debug_only(verify_map());
 300     } else {
 301       // ...or created from scratch
 302       JVMState* jvms = new (C) JVMState(_method, nullptr);
 303       jvms->set_bci(_bci);
 304       jvms->set_sp(_sp);
 305       jvms->set_map(new SafePointNode(TypeFunc::Parms, jvms));
 306       set_jvms(jvms);
 307       for (uint i = 0; i < map()->req(); i++)  map()->init_req(i, top());
 308       set_all_memory(top());
 309       while (map()->req() < jvms->endoff())  map()->add_req(top());
 310     }
 311     // (This is a kludge, in case you didn't notice.)
 312     set_control(top());
 313   }
 314   JVMState* jvms = sync_jvms();
 315   assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
 316   jvms->map()->set_next_exception(_exceptions);
 317   _exceptions = nullptr;   // done with this set of exceptions
 318   return jvms;
 319 }
 320 
 321 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
 322   assert(is_hidden_merge(dstphi), "must be a special merge node");
 323   assert(is_hidden_merge(srcphi), "must be a special merge node");
 324   uint limit = srcphi->req();
 325   for (uint i = PhiNode::Input; i < limit; i++) {
 326     dstphi->add_req(srcphi->in(i));
 327   }
 328 }
 329 static inline void add_one_req(Node* dstphi, Node* src) {
 330   assert(is_hidden_merge(dstphi), "must be a special merge node");
 331   assert(!is_hidden_merge(src), "must not be a special merge node");
 332   dstphi->add_req(src);
 333 }
 334 
 335 //-----------------------combine_exception_states------------------------------
 336 // This helper function combines exception states by building phis on a
 337 // specially marked state-merging region.  These regions and phis are
 338 // untransformed, and can build up gradually.  The region is marked by
 339 // having a control input of its exception map, rather than null.  Such
 340 // regions do not appear except in this function, and in use_exception_state.
 341 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
 342   if (failing_internal()) {
 343     return;  // dying anyway...
 344   }
 345   JVMState* ex_jvms = ex_map->_jvms;
 346   assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
 347   assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
 348   assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
 349   assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
 350   assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects");
 351   assert(ex_map->req() == phi_map->req(), "matching maps");
 352   uint tos = ex_jvms->stkoff() + ex_jvms->sp();
 353   Node*         hidden_merge_mark = root();
 354   Node*         region  = phi_map->control();
 355   MergeMemNode* phi_mem = phi_map->merged_memory();
 356   MergeMemNode* ex_mem  = ex_map->merged_memory();
 357   if (region->in(0) != hidden_merge_mark) {
 358     // The control input is not (yet) a specially-marked region in phi_map.
 359     // Make it so, and build some phis.
 360     region = new RegionNode(2);
 361     _gvn.set_type(region, Type::CONTROL);
 362     region->set_req(0, hidden_merge_mark);  // marks an internal ex-state
 363     region->init_req(1, phi_map->control());
 364     phi_map->set_control(region);
 365     Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
 366     record_for_igvn(io_phi);
 367     _gvn.set_type(io_phi, Type::ABIO);
 368     phi_map->set_i_o(io_phi);
 369     for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
 370       Node* m = mms.memory();
 371       Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
 372       record_for_igvn(m_phi);
 373       _gvn.set_type(m_phi, Type::MEMORY);
 374       mms.set_memory(m_phi);
 375     }
 376   }
 377 
 378   // Either or both of phi_map and ex_map might already be converted into phis.
 379   Node* ex_control = ex_map->control();
 380   // if there is special marking on ex_map also, we add multiple edges from src
 381   bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
 382   // how wide was the destination phi_map, originally?
 383   uint orig_width = region->req();
 384 
 385   if (add_multiple) {
 386     add_n_reqs(region, ex_control);
 387     add_n_reqs(phi_map->i_o(), ex_map->i_o());
 388   } else {
 389     // ex_map has no merges, so we just add single edges everywhere
 390     add_one_req(region, ex_control);
 391     add_one_req(phi_map->i_o(), ex_map->i_o());
 392   }
 393   for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
 394     if (mms.is_empty()) {
 395       // get a copy of the base memory, and patch some inputs into it
 396       const TypePtr* adr_type = mms.adr_type(C);
 397       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
 398       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
 399       mms.set_memory(phi);
 400       // Prepare to append interesting stuff onto the newly sliced phi:
 401       while (phi->req() > orig_width)  phi->del_req(phi->req()-1);
 402     }
 403     // Append stuff from ex_map:
 404     if (add_multiple) {
 405       add_n_reqs(mms.memory(), mms.memory2());
 406     } else {
 407       add_one_req(mms.memory(), mms.memory2());
 408     }
 409   }
 410   uint limit = ex_map->req();
 411   for (uint i = TypeFunc::Parms; i < limit; i++) {
 412     // Skip everything in the JVMS after tos.  (The ex_oop follows.)
 413     if (i == tos)  i = ex_jvms->monoff();
 414     Node* src = ex_map->in(i);
 415     Node* dst = phi_map->in(i);
 416     if (src != dst) {
 417       PhiNode* phi;
 418       if (dst->in(0) != region) {
 419         dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
 420         record_for_igvn(phi);
 421         _gvn.set_type(phi, phi->type());
 422         phi_map->set_req(i, dst);
 423         // Prepare to append interesting stuff onto the new phi:
 424         while (dst->req() > orig_width)  dst->del_req(dst->req()-1);
 425       } else {
 426         assert(dst->is_Phi(), "nobody else uses a hidden region");
 427         phi = dst->as_Phi();
 428       }
 429       if (add_multiple && src->in(0) == ex_control) {
 430         // Both are phis.
 431         add_n_reqs(dst, src);
 432       } else {
 433         while (dst->req() < region->req())  add_one_req(dst, src);
 434       }
 435       const Type* srctype = _gvn.type(src);
 436       if (phi->type() != srctype) {
 437         const Type* dsttype = phi->type()->meet_speculative(srctype);
 438         if (phi->type() != dsttype) {
 439           phi->set_type(dsttype);
 440           _gvn.set_type(phi, dsttype);
 441         }
 442       }
 443     }
 444   }
 445   phi_map->merge_replaced_nodes_with(ex_map);
 446 }
 447 
 448 //--------------------------use_exception_state--------------------------------
 449 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
 450   if (failing_internal()) { stop(); return top(); }
 451   Node* region = phi_map->control();
 452   Node* hidden_merge_mark = root();
 453   assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
 454   Node* ex_oop = clear_saved_ex_oop(phi_map);
 455   if (region->in(0) == hidden_merge_mark) {
 456     // Special marking for internal ex-states.  Process the phis now.
 457     region->set_req(0, region);  // now it's an ordinary region
 458     set_jvms(phi_map->jvms());   // ...so now we can use it as a map
 459     // Note: Setting the jvms also sets the bci and sp.
 460     set_control(_gvn.transform(region));
 461     uint tos = jvms()->stkoff() + sp();
 462     for (uint i = 1; i < tos; i++) {
 463       Node* x = phi_map->in(i);
 464       if (x->in(0) == region) {
 465         assert(x->is_Phi(), "expected a special phi");
 466         phi_map->set_req(i, _gvn.transform(x));
 467       }
 468     }
 469     for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
 470       Node* x = mms.memory();
 471       if (x->in(0) == region) {
 472         assert(x->is_Phi(), "nobody else uses a hidden region");
 473         mms.set_memory(_gvn.transform(x));
 474       }
 475     }
 476     if (ex_oop->in(0) == region) {
 477       assert(ex_oop->is_Phi(), "expected a special phi");
 478       ex_oop = _gvn.transform(ex_oop);
 479     }
 480   } else {
 481     set_jvms(phi_map->jvms());
 482   }
 483 
 484   assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
 485   assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
 486   return ex_oop;
 487 }
 488 
 489 //---------------------------------java_bc-------------------------------------
 490 Bytecodes::Code GraphKit::java_bc() const {
 491   ciMethod* method = this->method();
 492   int       bci    = this->bci();
 493   if (method != nullptr && bci != InvocationEntryBci)
 494     return method->java_code_at_bci(bci);
 495   else
 496     return Bytecodes::_illegal;
 497 }
 498 
 499 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
 500                                                           bool must_throw) {
 501     // if the exception capability is set, then we will generate code
 502     // to check the JavaThread.should_post_on_exceptions flag to see
 503     // if we actually need to report exception events (for this
 504     // thread).  If we don't need to report exception events, we will
 505     // take the normal fast path provided by add_exception_events.  If
 506     // exception event reporting is enabled for this thread, we will
 507     // take the uncommon_trap in the BuildCutout below.
 508 
 509     // first must access the should_post_on_exceptions_flag in this thread's JavaThread
 510     Node* jthread = _gvn.transform(new ThreadLocalNode());
 511     Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
 512     Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, MemNode::unordered);
 513 
 514     // Test the should_post_on_exceptions_flag vs. 0
 515     Node* chk = _gvn.transform( new CmpINode(should_post_flag, intcon(0)) );
 516     Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
 517 
 518     // Branch to slow_path if should_post_on_exceptions_flag was true
 519     { BuildCutout unless(this, tst, PROB_MAX);
 520       // Do not try anything fancy if we're notifying the VM on every throw.
 521       // Cf. case Bytecodes::_athrow in parse2.cpp.
 522       uncommon_trap(reason, Deoptimization::Action_none,
 523                     (ciKlass*)nullptr, (char*)nullptr, must_throw);
 524     }
 525 
 526 }
 527 
 528 //------------------------------builtin_throw----------------------------------
 529 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason) {
 530   bool must_throw = true;
 531 
 532   // If this particular condition has not yet happened at this
 533   // bytecode, then use the uncommon trap mechanism, and allow for
 534   // a future recompilation if several traps occur here.
 535   // If the throw is hot, try to use a more complicated inline mechanism
 536   // which keeps execution inside the compiled code.
 537   bool treat_throw_as_hot = false;
 538   ciMethodData* md = method()->method_data();
 539 
 540   if (ProfileTraps) {
 541     if (too_many_traps(reason)) {
 542       treat_throw_as_hot = true;
 543     }
 544     // (If there is no MDO at all, assume it is early in
 545     // execution, and that any deopts are part of the
 546     // startup transient, and don't need to be remembered.)
 547 
 548     // Also, if there is a local exception handler, treat all throws
 549     // as hot if there has been at least one in this method.
 550     if (C->trap_count(reason) != 0
 551         && method()->method_data()->trap_count(reason) != 0
 552         && has_exception_handler()) {
 553         treat_throw_as_hot = true;
 554     }
 555   }
 556 
 557   // If this throw happens frequently, an uncommon trap might cause
 558   // a performance pothole.  If there is a local exception handler,
 559   // and if this particular bytecode appears to be deoptimizing often,
 560   // let us handle the throw inline, with a preconstructed instance.
 561   // Note:   If the deopt count has blown up, the uncommon trap
 562   // runtime is going to flush this nmethod, not matter what.
 563   if (treat_throw_as_hot && method()->can_omit_stack_trace()) {
 564     // If the throw is local, we use a pre-existing instance and
 565     // punt on the backtrace.  This would lead to a missing backtrace
 566     // (a repeat of 4292742) if the backtrace object is ever asked
 567     // for its backtrace.
 568     // Fixing this remaining case of 4292742 requires some flavor of
 569     // escape analysis.  Leave that for the future.
 570     ciInstance* ex_obj = nullptr;
 571     switch (reason) {
 572     case Deoptimization::Reason_null_check:
 573       ex_obj = env()->NullPointerException_instance();
 574       break;
 575     case Deoptimization::Reason_div0_check:
 576       ex_obj = env()->ArithmeticException_instance();
 577       break;
 578     case Deoptimization::Reason_range_check:
 579       ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
 580       break;
 581     case Deoptimization::Reason_class_check:
 582       ex_obj = env()->ClassCastException_instance();
 583       break;
 584     case Deoptimization::Reason_array_check:
 585       ex_obj = env()->ArrayStoreException_instance();
 586       break;
 587     default:
 588       break;
 589     }
 590     if (failing()) { stop(); return; }  // exception allocation might fail
 591     if (ex_obj != nullptr) {
 592       if (env()->jvmti_can_post_on_exceptions()) {
 593         // check if we must post exception events, take uncommon trap if so
 594         uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
 595         // here if should_post_on_exceptions is false
 596         // continue on with the normal codegen
 597       }
 598 
 599       // Cheat with a preallocated exception object.
 600       if (C->log() != nullptr)
 601         C->log()->elem("hot_throw preallocated='1' reason='%s'",
 602                        Deoptimization::trap_reason_name(reason));
 603       const TypeInstPtr* ex_con  = TypeInstPtr::make(ex_obj);
 604       Node*              ex_node = _gvn.transform(ConNode::make(ex_con));
 605 
 606       // Clear the detail message of the preallocated exception object.
 607       // Weblogic sometimes mutates the detail message of exceptions
 608       // using reflection.
 609       int offset = java_lang_Throwable::get_detailMessage_offset();
 610       const TypePtr* adr_typ = ex_con->add_offset(offset);
 611 
 612       Node *adr = basic_plus_adr(ex_node, ex_node, offset);
 613       const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
 614       Node *store = access_store_at(ex_node, adr, adr_typ, null(), val_type, T_OBJECT, IN_HEAP);
 615 
 616       if (!method()->has_exception_handlers()) {
 617         // We don't need to preserve the stack if there's no handler as the entire frame is going to be popped anyway.
 618         // This prevents issues with exception handling and late inlining.
 619         set_sp(0);
 620         clean_stack(0);
 621       }
 622 
 623       add_exception_state(make_exception_state(ex_node));
 624       return;
 625     }
 626   }
 627 
 628   // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
 629   // It won't be much cheaper than bailing to the interp., since we'll
 630   // have to pass up all the debug-info, and the runtime will have to
 631   // create the stack trace.
 632 
 633   // Usual case:  Bail to interpreter.
 634   // Reserve the right to recompile if we haven't seen anything yet.
 635 
 636   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? C->method() : nullptr;
 637   Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
 638   if (treat_throw_as_hot
 639       && (method()->method_data()->trap_recompiled_at(bci(), m)
 640           || C->too_many_traps(reason))) {
 641     // We cannot afford to take more traps here.  Suffer in the interpreter.
 642     if (C->log() != nullptr)
 643       C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
 644                      Deoptimization::trap_reason_name(reason),
 645                      C->trap_count(reason));
 646     action = Deoptimization::Action_none;
 647   }
 648 
 649   // "must_throw" prunes the JVM state to include only the stack, if there
 650   // are no local exception handlers.  This should cut down on register
 651   // allocation time and code size, by drastically reducing the number
 652   // of in-edges on the call to the uncommon trap.
 653 
 654   uncommon_trap(reason, action, (ciKlass*)nullptr, (char*)nullptr, must_throw);
 655 }
 656 
 657 
 658 //----------------------------PreserveJVMState---------------------------------
 659 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
 660   debug_only(kit->verify_map());
 661   _kit    = kit;
 662   _map    = kit->map();   // preserve the map
 663   _sp     = kit->sp();
 664   kit->set_map(clone_map ? kit->clone_map() : nullptr);
 665 #ifdef ASSERT
 666   _bci    = kit->bci();
 667   Parse* parser = kit->is_Parse();
 668   int block = (parser == nullptr || parser->block() == nullptr) ? -1 : parser->block()->rpo();
 669   _block  = block;
 670 #endif
 671 }
 672 PreserveJVMState::~PreserveJVMState() {
 673   GraphKit* kit = _kit;
 674 #ifdef ASSERT
 675   assert(kit->bci() == _bci, "bci must not shift");
 676   Parse* parser = kit->is_Parse();
 677   int block = (parser == nullptr || parser->block() == nullptr) ? -1 : parser->block()->rpo();
 678   assert(block == _block,    "block must not shift");
 679 #endif
 680   kit->set_map(_map);
 681   kit->set_sp(_sp);
 682 }
 683 
 684 
 685 //-----------------------------BuildCutout-------------------------------------
 686 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
 687   : PreserveJVMState(kit)
 688 {
 689   assert(p->is_Con() || p->is_Bool(), "test must be a bool");
 690   SafePointNode* outer_map = _map;   // preserved map is caller's
 691   SafePointNode* inner_map = kit->map();
 692   IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
 693   outer_map->set_control(kit->gvn().transform( new IfTrueNode(iff) ));
 694   inner_map->set_control(kit->gvn().transform( new IfFalseNode(iff) ));
 695 }
 696 BuildCutout::~BuildCutout() {
 697   GraphKit* kit = _kit;
 698   assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
 699 }
 700 
 701 //---------------------------PreserveReexecuteState----------------------------
 702 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
 703   assert(!kit->stopped(), "must call stopped() before");
 704   _kit    =    kit;
 705   _sp     =    kit->sp();
 706   _reexecute = kit->jvms()->_reexecute;
 707 }
 708 PreserveReexecuteState::~PreserveReexecuteState() {
 709   if (_kit->stopped()) return;
 710   _kit->jvms()->_reexecute = _reexecute;
 711   _kit->set_sp(_sp);
 712 }
 713 
 714 //------------------------------clone_map--------------------------------------
 715 // Implementation of PreserveJVMState
 716 //
 717 // Only clone_map(...) here. If this function is only used in the
 718 // PreserveJVMState class we may want to get rid of this extra
 719 // function eventually and do it all there.
 720 
 721 SafePointNode* GraphKit::clone_map() {
 722   if (map() == nullptr)  return nullptr;
 723 
 724   // Clone the memory edge first
 725   Node* mem = MergeMemNode::make(map()->memory());
 726   gvn().set_type_bottom(mem);
 727 
 728   SafePointNode *clonemap = (SafePointNode*)map()->clone();
 729   JVMState* jvms = this->jvms();
 730   JVMState* clonejvms = jvms->clone_shallow(C);
 731   clonemap->set_memory(mem);
 732   clonemap->set_jvms(clonejvms);
 733   clonejvms->set_map(clonemap);
 734   record_for_igvn(clonemap);
 735   gvn().set_type_bottom(clonemap);
 736   return clonemap;
 737 }
 738 
 739 //-----------------------------destruct_map_clone------------------------------
 740 //
 741 // Order of destruct is important to increase the likelyhood that memory can be re-used. We need
 742 // to destruct/free/delete in the exact opposite order as clone_map().
 743 void GraphKit::destruct_map_clone(SafePointNode* sfp) {
 744   if (sfp == nullptr) return;
 745 
 746   Node* mem = sfp->memory();
 747   JVMState* jvms = sfp->jvms();
 748 
 749   if (jvms != nullptr) {
 750     delete jvms;
 751   }
 752 
 753   remove_for_igvn(sfp);
 754   gvn().clear_type(sfp);
 755   sfp->destruct(&_gvn);
 756 
 757   if (mem != nullptr) {
 758     gvn().clear_type(mem);
 759     mem->destruct(&_gvn);
 760   }
 761 }
 762 
 763 //-----------------------------set_map_clone-----------------------------------
 764 void GraphKit::set_map_clone(SafePointNode* m) {
 765   _map = m;
 766   _map = clone_map();
 767   _map->set_next_exception(nullptr);
 768   debug_only(verify_map());
 769 }
 770 
 771 
 772 //----------------------------kill_dead_locals---------------------------------
 773 // Detect any locals which are known to be dead, and force them to top.
 774 void GraphKit::kill_dead_locals() {
 775   // Consult the liveness information for the locals.  If any
 776   // of them are unused, then they can be replaced by top().  This
 777   // should help register allocation time and cut down on the size
 778   // of the deoptimization information.
 779 
 780   // This call is made from many of the bytecode handling
 781   // subroutines called from the Big Switch in do_one_bytecode.
 782   // Every bytecode which might include a slow path is responsible
 783   // for killing its dead locals.  The more consistent we
 784   // are about killing deads, the fewer useless phis will be
 785   // constructed for them at various merge points.
 786 
 787   // bci can be -1 (InvocationEntryBci).  We return the entry
 788   // liveness for the method.
 789 
 790   if (method() == nullptr || method()->code_size() == 0) {
 791     // We are building a graph for a call to a native method.
 792     // All locals are live.
 793     return;
 794   }
 795 
 796   ResourceMark rm;
 797 
 798   // Consult the liveness information for the locals.  If any
 799   // of them are unused, then they can be replaced by top().  This
 800   // should help register allocation time and cut down on the size
 801   // of the deoptimization information.
 802   MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
 803 
 804   int len = (int)live_locals.size();
 805   assert(len <= jvms()->loc_size(), "too many live locals");
 806   for (int local = 0; local < len; local++) {
 807     if (!live_locals.at(local)) {
 808       set_local(local, top());
 809     }
 810   }
 811 }
 812 
 813 #ifdef ASSERT
 814 //-------------------------dead_locals_are_killed------------------------------
 815 // Return true if all dead locals are set to top in the map.
 816 // Used to assert "clean" debug info at various points.
 817 bool GraphKit::dead_locals_are_killed() {
 818   if (method() == nullptr || method()->code_size() == 0) {
 819     // No locals need to be dead, so all is as it should be.
 820     return true;
 821   }
 822 
 823   // Make sure somebody called kill_dead_locals upstream.
 824   ResourceMark rm;
 825   for (JVMState* jvms = this->jvms(); jvms != nullptr; jvms = jvms->caller()) {
 826     if (jvms->loc_size() == 0)  continue;  // no locals to consult
 827     SafePointNode* map = jvms->map();
 828     ciMethod* method = jvms->method();
 829     int       bci    = jvms->bci();
 830     if (jvms == this->jvms()) {
 831       bci = this->bci();  // it might not yet be synched
 832     }
 833     MethodLivenessResult live_locals = method->liveness_at_bci(bci);
 834     int len = (int)live_locals.size();
 835     if (!live_locals.is_valid() || len == 0)
 836       // This method is trivial, or is poisoned by a breakpoint.
 837       return true;
 838     assert(len == jvms->loc_size(), "live map consistent with locals map");
 839     for (int local = 0; local < len; local++) {
 840       if (!live_locals.at(local) && map->local(jvms, local) != top()) {
 841         if (PrintMiscellaneous && (Verbose || WizardMode)) {
 842           tty->print_cr("Zombie local %d: ", local);
 843           jvms->dump();
 844         }
 845         return false;
 846       }
 847     }
 848   }
 849   return true;
 850 }
 851 
 852 #endif //ASSERT
 853 
 854 // Helper function for enforcing certain bytecodes to reexecute if deoptimization happens.
 855 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
 856   ciMethod* cur_method = jvms->method();
 857   int       cur_bci   = jvms->bci();
 858   if (cur_method != nullptr && cur_bci != InvocationEntryBci) {
 859     Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
 860     return Interpreter::bytecode_should_reexecute(code) ||
 861            (is_anewarray && code == Bytecodes::_multianewarray);
 862     // Reexecute _multianewarray bytecode which was replaced with
 863     // sequence of [a]newarray. See Parse::do_multianewarray().
 864     //
 865     // Note: interpreter should not have it set since this optimization
 866     // is limited by dimensions and guarded by flag so in some cases
 867     // multianewarray() runtime calls will be generated and
 868     // the bytecode should not be reexecutes (stack will not be reset).
 869   } else {
 870     return false;
 871   }
 872 }
 873 
 874 // Helper function for adding JVMState and debug information to node
 875 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
 876   // Add the safepoint edges to the call (or other safepoint).
 877 
 878   // Make sure dead locals are set to top.  This
 879   // should help register allocation time and cut down on the size
 880   // of the deoptimization information.
 881   assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
 882 
 883   // Walk the inline list to fill in the correct set of JVMState's
 884   // Also fill in the associated edges for each JVMState.
 885 
 886   // If the bytecode needs to be reexecuted we need to put
 887   // the arguments back on the stack.
 888   const bool should_reexecute = jvms()->should_reexecute();
 889   JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
 890 
 891   // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
 892   // undefined if the bci is different.  This is normal for Parse but it
 893   // should not happen for LibraryCallKit because only one bci is processed.
 894   assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
 895          "in LibraryCallKit the reexecute bit should not change");
 896 
 897   // If we are guaranteed to throw, we can prune everything but the
 898   // input to the current bytecode.
 899   bool can_prune_locals = false;
 900   uint stack_slots_not_pruned = 0;
 901   int inputs = 0, depth = 0;
 902   if (must_throw) {
 903     assert(method() == youngest_jvms->method(), "sanity");
 904     if (compute_stack_effects(inputs, depth)) {
 905       can_prune_locals = true;
 906       stack_slots_not_pruned = inputs;
 907     }
 908   }
 909 
 910   if (env()->should_retain_local_variables()) {
 911     // At any safepoint, this method can get breakpointed, which would
 912     // then require an immediate deoptimization.
 913     can_prune_locals = false;  // do not prune locals
 914     stack_slots_not_pruned = 0;
 915   }
 916 
 917   // do not scribble on the input jvms
 918   JVMState* out_jvms = youngest_jvms->clone_deep(C);
 919   call->set_jvms(out_jvms); // Start jvms list for call node
 920 
 921   // For a known set of bytecodes, the interpreter should reexecute them if
 922   // deoptimization happens. We set the reexecute state for them here
 923   if (out_jvms->is_reexecute_undefined() && //don't change if already specified
 924       should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
 925 #ifdef ASSERT
 926     int inputs = 0, not_used; // initialized by GraphKit::compute_stack_effects()
 927     assert(method() == youngest_jvms->method(), "sanity");
 928     assert(compute_stack_effects(inputs, not_used), "unknown bytecode: %s", Bytecodes::name(java_bc()));
 929     assert(out_jvms->sp() >= (uint)inputs, "not enough operands for reexecution");
 930 #endif // ASSERT
 931     out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
 932   }
 933 
 934   // Presize the call:
 935   DEBUG_ONLY(uint non_debug_edges = call->req());
 936   call->add_req_batch(top(), youngest_jvms->debug_depth());
 937   assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
 938 
 939   // Set up edges so that the call looks like this:
 940   //  Call [state:] ctl io mem fptr retadr
 941   //       [parms:] parm0 ... parmN
 942   //       [root:]  loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 943   //    [...mid:]   loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
 944   //       [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 945   // Note that caller debug info precedes callee debug info.
 946 
 947   // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
 948   uint debug_ptr = call->req();
 949 
 950   // Loop over the map input edges associated with jvms, add them
 951   // to the call node, & reset all offsets to match call node array.
 952   for (JVMState* in_jvms = youngest_jvms; in_jvms != nullptr; ) {
 953     uint debug_end   = debug_ptr;
 954     uint debug_start = debug_ptr - in_jvms->debug_size();
 955     debug_ptr = debug_start;  // back up the ptr
 956 
 957     uint p = debug_start;  // walks forward in [debug_start, debug_end)
 958     uint j, k, l;
 959     SafePointNode* in_map = in_jvms->map();
 960     out_jvms->set_map(call);
 961 
 962     if (can_prune_locals) {
 963       assert(in_jvms->method() == out_jvms->method(), "sanity");
 964       // If the current throw can reach an exception handler in this JVMS,
 965       // then we must keep everything live that can reach that handler.
 966       // As a quick and dirty approximation, we look for any handlers at all.
 967       if (in_jvms->method()->has_exception_handlers()) {
 968         can_prune_locals = false;
 969       }
 970     }
 971 
 972     // Add the Locals
 973     k = in_jvms->locoff();
 974     l = in_jvms->loc_size();
 975     out_jvms->set_locoff(p);
 976     if (!can_prune_locals) {
 977       for (j = 0; j < l; j++)
 978         call->set_req(p++, in_map->in(k+j));
 979     } else {
 980       p += l;  // already set to top above by add_req_batch
 981     }
 982 
 983     // Add the Expression Stack
 984     k = in_jvms->stkoff();
 985     l = in_jvms->sp();
 986     out_jvms->set_stkoff(p);
 987     if (!can_prune_locals) {
 988       for (j = 0; j < l; j++)
 989         call->set_req(p++, in_map->in(k+j));
 990     } else if (can_prune_locals && stack_slots_not_pruned != 0) {
 991       // Divide stack into {S0,...,S1}, where S0 is set to top.
 992       uint s1 = stack_slots_not_pruned;
 993       stack_slots_not_pruned = 0;  // for next iteration
 994       if (s1 > l)  s1 = l;
 995       uint s0 = l - s1;
 996       p += s0;  // skip the tops preinstalled by add_req_batch
 997       for (j = s0; j < l; j++)
 998         call->set_req(p++, in_map->in(k+j));
 999     } else {
1000       p += l;  // already set to top above by add_req_batch
1001     }
1002 
1003     // Add the Monitors
1004     k = in_jvms->monoff();
1005     l = in_jvms->mon_size();
1006     out_jvms->set_monoff(p);
1007     for (j = 0; j < l; j++)
1008       call->set_req(p++, in_map->in(k+j));
1009 
1010     // Copy any scalar object fields.
1011     k = in_jvms->scloff();
1012     l = in_jvms->scl_size();
1013     out_jvms->set_scloff(p);
1014     for (j = 0; j < l; j++)
1015       call->set_req(p++, in_map->in(k+j));
1016 
1017     // Finish the new jvms.
1018     out_jvms->set_endoff(p);
1019 
1020     assert(out_jvms->endoff()     == debug_end,             "fill ptr must match");
1021     assert(out_jvms->depth()      == in_jvms->depth(),      "depth must match");
1022     assert(out_jvms->loc_size()   == in_jvms->loc_size(),   "size must match");
1023     assert(out_jvms->mon_size()   == in_jvms->mon_size(),   "size must match");
1024     assert(out_jvms->scl_size()   == in_jvms->scl_size(),   "size must match");
1025     assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
1026 
1027     // Update the two tail pointers in parallel.
1028     out_jvms = out_jvms->caller();
1029     in_jvms  = in_jvms->caller();
1030   }
1031 
1032   assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
1033 
1034   // Test the correctness of JVMState::debug_xxx accessors:
1035   assert(call->jvms()->debug_start() == non_debug_edges, "");
1036   assert(call->jvms()->debug_end()   == call->req(), "");
1037   assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
1038 }
1039 
1040 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
1041   Bytecodes::Code code = java_bc();
1042   if (code == Bytecodes::_wide) {
1043     code = method()->java_code_at_bci(bci() + 1);
1044   }
1045 
1046   if (code != Bytecodes::_illegal) {
1047     depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1048   }
1049 
1050   auto rsize = [&]() {
1051     assert(code != Bytecodes::_illegal, "code is illegal!");
1052     BasicType rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1053     return (rtype < T_CONFLICT) ? type2size[rtype] : 0;
1054   };
1055 
1056   switch (code) {
1057   case Bytecodes::_illegal:
1058     return false;
1059 
1060   case Bytecodes::_ldc:
1061   case Bytecodes::_ldc_w:
1062   case Bytecodes::_ldc2_w:
1063     inputs = 0;
1064     break;
1065 
1066   case Bytecodes::_dup:         inputs = 1;  break;
1067   case Bytecodes::_dup_x1:      inputs = 2;  break;
1068   case Bytecodes::_dup_x2:      inputs = 3;  break;
1069   case Bytecodes::_dup2:        inputs = 2;  break;
1070   case Bytecodes::_dup2_x1:     inputs = 3;  break;
1071   case Bytecodes::_dup2_x2:     inputs = 4;  break;
1072   case Bytecodes::_swap:        inputs = 2;  break;
1073   case Bytecodes::_arraylength: inputs = 1;  break;
1074 
1075   case Bytecodes::_getstatic:
1076   case Bytecodes::_putstatic:
1077   case Bytecodes::_getfield:
1078   case Bytecodes::_putfield:
1079     {
1080       bool ignored_will_link;
1081       ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1082       int      size  = field->type()->size();
1083       bool is_get = (depth >= 0), is_static = (depth & 1);
1084       inputs = (is_static ? 0 : 1);
1085       if (is_get) {
1086         depth = size - inputs;
1087       } else {
1088         inputs += size;        // putxxx pops the value from the stack
1089         depth = - inputs;
1090       }
1091     }
1092     break;
1093 
1094   case Bytecodes::_invokevirtual:
1095   case Bytecodes::_invokespecial:
1096   case Bytecodes::_invokestatic:
1097   case Bytecodes::_invokedynamic:
1098   case Bytecodes::_invokeinterface:
1099     {
1100       bool ignored_will_link;
1101       ciSignature* declared_signature = nullptr;
1102       ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1103       assert(declared_signature != nullptr, "cannot be null");
1104       inputs   = declared_signature->arg_size_for_bc(code);
1105       int size = declared_signature->return_type()->size();
1106       depth = size - inputs;
1107     }
1108     break;
1109 
1110   case Bytecodes::_multianewarray:
1111     {
1112       ciBytecodeStream iter(method());
1113       iter.reset_to_bci(bci());
1114       iter.next();
1115       inputs = iter.get_dimensions();
1116       assert(rsize() == 1, "");
1117       depth = 1 - inputs;
1118     }
1119     break;
1120 
1121   case Bytecodes::_ireturn:
1122   case Bytecodes::_lreturn:
1123   case Bytecodes::_freturn:
1124   case Bytecodes::_dreturn:
1125   case Bytecodes::_areturn:
1126     assert(rsize() == -depth, "");
1127     inputs = -depth;
1128     break;
1129 
1130   case Bytecodes::_jsr:
1131   case Bytecodes::_jsr_w:
1132     inputs = 0;
1133     depth  = 1;                  // S.B. depth=1, not zero
1134     break;
1135 
1136   default:
1137     // bytecode produces a typed result
1138     inputs = rsize() - depth;
1139     assert(inputs >= 0, "");
1140     break;
1141   }
1142 
1143 #ifdef ASSERT
1144   // spot check
1145   int outputs = depth + inputs;
1146   assert(outputs >= 0, "sanity");
1147   switch (code) {
1148   case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1149   case Bytecodes::_athrow:    assert(inputs == 1 && outputs == 0, ""); break;
1150   case Bytecodes::_aload_0:   assert(inputs == 0 && outputs == 1, ""); break;
1151   case Bytecodes::_return:    assert(inputs == 0 && outputs == 0, ""); break;
1152   case Bytecodes::_drem:      assert(inputs == 4 && outputs == 2, ""); break;
1153   default:                    break;
1154   }
1155 #endif //ASSERT
1156 
1157   return true;
1158 }
1159 
1160 
1161 
1162 //------------------------------basic_plus_adr---------------------------------
1163 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1164   // short-circuit a common case
1165   if (offset == intcon(0))  return ptr;
1166   return _gvn.transform( new AddPNode(base, ptr, offset) );
1167 }
1168 
1169 Node* GraphKit::ConvI2L(Node* offset) {
1170   // short-circuit a common case
1171   jint offset_con = find_int_con(offset, Type::OffsetBot);
1172   if (offset_con != Type::OffsetBot) {
1173     return longcon((jlong) offset_con);
1174   }
1175   return _gvn.transform( new ConvI2LNode(offset));
1176 }
1177 
1178 Node* GraphKit::ConvI2UL(Node* offset) {
1179   juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1180   if (offset_con != (juint) Type::OffsetBot) {
1181     return longcon((julong) offset_con);
1182   }
1183   Node* conv = _gvn.transform( new ConvI2LNode(offset));
1184   Node* mask = _gvn.transform(ConLNode::make((julong) max_juint));
1185   return _gvn.transform( new AndLNode(conv, mask) );
1186 }
1187 
1188 Node* GraphKit::ConvL2I(Node* offset) {
1189   // short-circuit a common case
1190   jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1191   if (offset_con != (jlong)Type::OffsetBot) {
1192     return intcon((int) offset_con);
1193   }
1194   return _gvn.transform( new ConvL2INode(offset));
1195 }
1196 
1197 //-------------------------load_object_klass-----------------------------------
1198 Node* GraphKit::load_object_klass(Node* obj) {
1199   // Special-case a fresh allocation to avoid building nodes:
1200   Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1201   if (akls != nullptr)  return akls;
1202   Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1203   return _gvn.transform(LoadKlassNode::make(_gvn, immutable_memory(), k_adr, TypeInstPtr::KLASS));
1204 }
1205 
1206 //-------------------------load_array_length-----------------------------------
1207 Node* GraphKit::load_array_length(Node* array) {
1208   // Special-case a fresh allocation to avoid building nodes:
1209   AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array);
1210   Node *alen;
1211   if (alloc == nullptr) {
1212     Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1213     alen = _gvn.transform( new LoadRangeNode(nullptr, immutable_memory(), r_adr, TypeInt::POS));
1214   } else {
1215     alen = array_ideal_length(alloc, _gvn.type(array)->is_oopptr(), false);
1216   }
1217   return alen;
1218 }
1219 
1220 Node* GraphKit::array_ideal_length(AllocateArrayNode* alloc,
1221                                    const TypeOopPtr* oop_type,
1222                                    bool replace_length_in_map) {
1223   Node* length = alloc->Ideal_length();
1224   if (replace_length_in_map == false || map()->find_edge(length) >= 0) {
1225     Node* ccast = alloc->make_ideal_length(oop_type, &_gvn);
1226     if (ccast != length) {
1227       // do not transform ccast here, it might convert to top node for
1228       // negative array length and break assumptions in parsing stage.
1229       _gvn.set_type_bottom(ccast);
1230       record_for_igvn(ccast);
1231       if (replace_length_in_map) {
1232         replace_in_map(length, ccast);
1233       }
1234       return ccast;
1235     }
1236   }
1237   return length;
1238 }
1239 
1240 //------------------------------do_null_check----------------------------------
1241 // Helper function to do a null pointer check.  Returned value is
1242 // the incoming address with null casted away.  You are allowed to use the
1243 // not-null value only if you are control dependent on the test.
1244 #ifndef PRODUCT
1245 extern uint explicit_null_checks_inserted,
1246             explicit_null_checks_elided;
1247 #endif
1248 Node* GraphKit::null_check_common(Node* value, BasicType type,
1249                                   // optional arguments for variations:
1250                                   bool assert_null,
1251                                   Node* *null_control,
1252                                   bool speculative) {
1253   assert(!assert_null || null_control == nullptr, "not both at once");
1254   if (stopped())  return top();
1255   NOT_PRODUCT(explicit_null_checks_inserted++);
1256 
1257   // Construct null check
1258   Node *chk = nullptr;
1259   switch(type) {
1260     case T_LONG   : chk = new CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1261     case T_INT    : chk = new CmpINode(value, _gvn.intcon(0)); break;
1262     case T_ARRAY  : // fall through
1263       type = T_OBJECT;  // simplify further tests
1264     case T_OBJECT : {
1265       const Type *t = _gvn.type( value );
1266 
1267       const TypeOopPtr* tp = t->isa_oopptr();
1268       if (tp != nullptr && !tp->is_loaded()
1269           // Only for do_null_check, not any of its siblings:
1270           && !assert_null && null_control == nullptr) {
1271         // Usually, any field access or invocation on an unloaded oop type
1272         // will simply fail to link, since the statically linked class is
1273         // likely also to be unloaded.  However, in -Xcomp mode, sometimes
1274         // the static class is loaded but the sharper oop type is not.
1275         // Rather than checking for this obscure case in lots of places,
1276         // we simply observe that a null check on an unloaded class
1277         // will always be followed by a nonsense operation, so we
1278         // can just issue the uncommon trap here.
1279         // Our access to the unloaded class will only be correct
1280         // after it has been loaded and initialized, which requires
1281         // a trip through the interpreter.
1282         ciKlass* klass = tp->unloaded_klass();
1283 #ifndef PRODUCT
1284         if (WizardMode) { tty->print("Null check of unloaded "); klass->print(); tty->cr(); }
1285 #endif
1286         uncommon_trap(Deoptimization::Reason_unloaded,
1287                       Deoptimization::Action_reinterpret,
1288                       klass, "!loaded");
1289         return top();
1290       }
1291 
1292       if (assert_null) {
1293         // See if the type is contained in NULL_PTR.
1294         // If so, then the value is already null.
1295         if (t->higher_equal(TypePtr::NULL_PTR)) {
1296           NOT_PRODUCT(explicit_null_checks_elided++);
1297           return value;           // Elided null assert quickly!
1298         }
1299       } else {
1300         // See if mixing in the null pointer changes type.
1301         // If so, then the null pointer was not allowed in the original
1302         // type.  In other words, "value" was not-null.
1303         if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1304           // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1305           NOT_PRODUCT(explicit_null_checks_elided++);
1306           return value;           // Elided null check quickly!
1307         }
1308       }
1309       chk = new CmpPNode( value, null() );
1310       break;
1311     }
1312 
1313     default:
1314       fatal("unexpected type: %s", type2name(type));
1315   }
1316   assert(chk != nullptr, "sanity check");
1317   chk = _gvn.transform(chk);
1318 
1319   BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1320   BoolNode *btst = new BoolNode( chk, btest);
1321   Node   *tst = _gvn.transform( btst );
1322 
1323   //-----------
1324   // if peephole optimizations occurred, a prior test existed.
1325   // If a prior test existed, maybe it dominates as we can avoid this test.
1326   if (tst != btst && type == T_OBJECT) {
1327     // At this point we want to scan up the CFG to see if we can
1328     // find an identical test (and so avoid this test altogether).
1329     Node *cfg = control();
1330     int depth = 0;
1331     while( depth < 16 ) {       // Limit search depth for speed
1332       if( cfg->Opcode() == Op_IfTrue &&
1333           cfg->in(0)->in(1) == tst ) {
1334         // Found prior test.  Use "cast_not_null" to construct an identical
1335         // CastPP (and hence hash to) as already exists for the prior test.
1336         // Return that casted value.
1337         if (assert_null) {
1338           replace_in_map(value, null());
1339           return null();  // do not issue the redundant test
1340         }
1341         Node *oldcontrol = control();
1342         set_control(cfg);
1343         Node *res = cast_not_null(value);
1344         set_control(oldcontrol);
1345         NOT_PRODUCT(explicit_null_checks_elided++);
1346         return res;
1347       }
1348       cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1349       if (cfg == nullptr)  break;  // Quit at region nodes
1350       depth++;
1351     }
1352   }
1353 
1354   //-----------
1355   // Branch to failure if null
1356   float ok_prob = PROB_MAX;  // a priori estimate:  nulls never happen
1357   Deoptimization::DeoptReason reason;
1358   if (assert_null) {
1359     reason = Deoptimization::reason_null_assert(speculative);
1360   } else if (type == T_OBJECT) {
1361     reason = Deoptimization::reason_null_check(speculative);
1362   } else {
1363     reason = Deoptimization::Reason_div0_check;
1364   }
1365   // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1366   // ciMethodData::has_trap_at will return a conservative -1 if any
1367   // must-be-null assertion has failed.  This could cause performance
1368   // problems for a method after its first do_null_assert failure.
1369   // Consider using 'Reason_class_check' instead?
1370 
1371   // To cause an implicit null check, we set the not-null probability
1372   // to the maximum (PROB_MAX).  For an explicit check the probability
1373   // is set to a smaller value.
1374   if (null_control != nullptr || too_many_traps(reason)) {
1375     // probability is less likely
1376     ok_prob =  PROB_LIKELY_MAG(3);
1377   } else if (!assert_null &&
1378              (ImplicitNullCheckThreshold > 0) &&
1379              method() != nullptr &&
1380              (method()->method_data()->trap_count(reason)
1381               >= (uint)ImplicitNullCheckThreshold)) {
1382     ok_prob =  PROB_LIKELY_MAG(3);
1383   }
1384 
1385   if (null_control != nullptr) {
1386     IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1387     Node* null_true = _gvn.transform( new IfFalseNode(iff));
1388     set_control(      _gvn.transform( new IfTrueNode(iff)));
1389 #ifndef PRODUCT
1390     if (null_true == top()) {
1391       explicit_null_checks_elided++;
1392     }
1393 #endif
1394     (*null_control) = null_true;
1395   } else {
1396     BuildCutout unless(this, tst, ok_prob);
1397     // Check for optimizer eliding test at parse time
1398     if (stopped()) {
1399       // Failure not possible; do not bother making uncommon trap.
1400       NOT_PRODUCT(explicit_null_checks_elided++);
1401     } else if (assert_null) {
1402       uncommon_trap(reason,
1403                     Deoptimization::Action_make_not_entrant,
1404                     nullptr, "assert_null");
1405     } else {
1406       replace_in_map(value, zerocon(type));
1407       builtin_throw(reason);
1408     }
1409   }
1410 
1411   // Must throw exception, fall-thru not possible?
1412   if (stopped()) {
1413     return top();               // No result
1414   }
1415 
1416   if (assert_null) {
1417     // Cast obj to null on this path.
1418     replace_in_map(value, zerocon(type));
1419     return zerocon(type);
1420   }
1421 
1422   // Cast obj to not-null on this path, if there is no null_control.
1423   // (If there is a null_control, a non-null value may come back to haunt us.)
1424   if (type == T_OBJECT) {
1425     Node* cast = cast_not_null(value, false);
1426     if (null_control == nullptr || (*null_control) == top())
1427       replace_in_map(value, cast);
1428     value = cast;
1429   }
1430 
1431   return value;
1432 }
1433 
1434 
1435 //------------------------------cast_not_null----------------------------------
1436 // Cast obj to not-null on this path
1437 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1438   const Type *t = _gvn.type(obj);
1439   const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1440   // Object is already not-null?
1441   if( t == t_not_null ) return obj;
1442 
1443   Node* cast = new CastPPNode(control(), obj,t_not_null);
1444   cast = _gvn.transform( cast );
1445 
1446   // Scan for instances of 'obj' in the current JVM mapping.
1447   // These instances are known to be not-null after the test.
1448   if (do_replace_in_map)
1449     replace_in_map(obj, cast);
1450 
1451   return cast;                  // Return casted value
1452 }
1453 
1454 // Sometimes in intrinsics, we implicitly know an object is not null
1455 // (there's no actual null check) so we can cast it to not null. In
1456 // the course of optimizations, the input to the cast can become null.
1457 // In that case that data path will die and we need the control path
1458 // to become dead as well to keep the graph consistent. So we have to
1459 // add a check for null for which one branch can't be taken. It uses
1460 // an OpaqueNotNull node that will cause the check to be removed after loop
1461 // opts so the test goes away and the compiled code doesn't execute a
1462 // useless check.
1463 Node* GraphKit::must_be_not_null(Node* value, bool do_replace_in_map) {
1464   if (!TypePtr::NULL_PTR->higher_equal(_gvn.type(value))) {
1465     return value;
1466   }
1467   Node* chk = _gvn.transform(new CmpPNode(value, null()));
1468   Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::ne));
1469   Node* opaq = _gvn.transform(new OpaqueNotNullNode(C, tst));
1470   IfNode* iff = new IfNode(control(), opaq, PROB_MAX, COUNT_UNKNOWN);
1471   _gvn.set_type(iff, iff->Value(&_gvn));
1472   if (!tst->is_Con()) {
1473     record_for_igvn(iff);
1474   }
1475   Node *if_f = _gvn.transform(new IfFalseNode(iff));
1476   Node *frame = _gvn.transform(new ParmNode(C->start(), TypeFunc::FramePtr));
1477   Node* halt = _gvn.transform(new HaltNode(if_f, frame, "unexpected null in intrinsic"));
1478   C->root()->add_req(halt);
1479   Node *if_t = _gvn.transform(new IfTrueNode(iff));
1480   set_control(if_t);
1481   return cast_not_null(value, do_replace_in_map);
1482 }
1483 
1484 
1485 //--------------------------replace_in_map-------------------------------------
1486 void GraphKit::replace_in_map(Node* old, Node* neww) {
1487   if (old == neww) {
1488     return;
1489   }
1490 
1491   map()->replace_edge(old, neww);
1492 
1493   // Note: This operation potentially replaces any edge
1494   // on the map.  This includes locals, stack, and monitors
1495   // of the current (innermost) JVM state.
1496 
1497   // don't let inconsistent types from profiling escape this
1498   // method
1499 
1500   const Type* told = _gvn.type(old);
1501   const Type* tnew = _gvn.type(neww);
1502 
1503   if (!tnew->higher_equal(told)) {
1504     return;
1505   }
1506 
1507   map()->record_replaced_node(old, neww);
1508 }
1509 
1510 
1511 //=============================================================================
1512 //--------------------------------memory---------------------------------------
1513 Node* GraphKit::memory(uint alias_idx) {
1514   MergeMemNode* mem = merged_memory();
1515   Node* p = mem->memory_at(alias_idx);
1516   assert(p != mem->empty_memory(), "empty");
1517   _gvn.set_type(p, Type::MEMORY);  // must be mapped
1518   return p;
1519 }
1520 
1521 //-----------------------------reset_memory------------------------------------
1522 Node* GraphKit::reset_memory() {
1523   Node* mem = map()->memory();
1524   // do not use this node for any more parsing!
1525   debug_only( map()->set_memory((Node*)nullptr) );
1526   return _gvn.transform( mem );
1527 }
1528 
1529 //------------------------------set_all_memory---------------------------------
1530 void GraphKit::set_all_memory(Node* newmem) {
1531   Node* mergemem = MergeMemNode::make(newmem);
1532   gvn().set_type_bottom(mergemem);
1533   map()->set_memory(mergemem);
1534 }
1535 
1536 //------------------------------set_all_memory_call----------------------------
1537 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1538   Node* newmem = _gvn.transform( new ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1539   set_all_memory(newmem);
1540 }
1541 
1542 //=============================================================================
1543 //
1544 // parser factory methods for MemNodes
1545 //
1546 // These are layered on top of the factory methods in LoadNode and StoreNode,
1547 // and integrate with the parser's memory state and _gvn engine.
1548 //
1549 
1550 // factory methods in "int adr_idx"
1551 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1552                           MemNode::MemOrd mo,
1553                           LoadNode::ControlDependency control_dependency,
1554                           bool require_atomic_access,
1555                           bool unaligned,
1556                           bool mismatched,
1557                           bool unsafe,
1558                           uint8_t barrier_data) {
1559   int adr_idx = C->get_alias_index(_gvn.type(adr)->isa_ptr());
1560   assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1561   const TypePtr* adr_type = nullptr; // debug-mode-only argument
1562   debug_only(adr_type = C->get_adr_type(adr_idx));
1563   Node* mem = memory(adr_idx);
1564   Node* ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, require_atomic_access, unaligned, mismatched, unsafe, barrier_data);
1565   ld = _gvn.transform(ld);
1566   if (((bt == T_OBJECT) && C->do_escape_analysis()) || C->eliminate_boxing()) {
1567     // Improve graph before escape analysis and boxing elimination.
1568     record_for_igvn(ld);
1569     if (ld->is_DecodeN()) {
1570       // Also record the actual load (LoadN) in case ld is DecodeN. In some
1571       // rare corner cases, ld->in(1) can be something other than LoadN (e.g.,
1572       // a Phi). Recording such cases is still perfectly sound, but may be
1573       // unnecessary and result in some minor IGVN overhead.
1574       record_for_igvn(ld->in(1));
1575     }
1576   }
1577   return ld;
1578 }
1579 
1580 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1581                                 MemNode::MemOrd mo,
1582                                 bool require_atomic_access,
1583                                 bool unaligned,
1584                                 bool mismatched,
1585                                 bool unsafe,
1586                                 int barrier_data) {
1587   int adr_idx = C->get_alias_index(_gvn.type(adr)->isa_ptr());
1588   assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1589   const TypePtr* adr_type = nullptr;
1590   debug_only(adr_type = C->get_adr_type(adr_idx));
1591   Node *mem = memory(adr_idx);
1592   Node* st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo, require_atomic_access);
1593   if (unaligned) {
1594     st->as_Store()->set_unaligned_access();
1595   }
1596   if (mismatched) {
1597     st->as_Store()->set_mismatched_access();
1598   }
1599   if (unsafe) {
1600     st->as_Store()->set_unsafe_access();
1601   }
1602   st->as_Store()->set_barrier_data(barrier_data);
1603   st = _gvn.transform(st);
1604   set_memory(st, adr_idx);
1605   // Back-to-back stores can only remove intermediate store with DU info
1606   // so push on worklist for optimizer.
1607   if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1608     record_for_igvn(st);
1609 
1610   return st;
1611 }
1612 
1613 Node* GraphKit::access_store_at(Node* obj,
1614                                 Node* adr,
1615                                 const TypePtr* adr_type,
1616                                 Node* val,
1617                                 const Type* val_type,
1618                                 BasicType bt,
1619                                 DecoratorSet decorators) {
1620   // Transformation of a value which could be null pointer (CastPP #null)
1621   // could be delayed during Parse (for example, in adjust_map_after_if()).
1622   // Execute transformation here to avoid barrier generation in such case.
1623   if (_gvn.type(val) == TypePtr::NULL_PTR) {
1624     val = _gvn.makecon(TypePtr::NULL_PTR);
1625   }
1626 
1627   if (stopped()) {
1628     return top(); // Dead path ?
1629   }
1630 
1631   assert(val != nullptr, "not dead path");
1632 
1633   C2AccessValuePtr addr(adr, adr_type);
1634   C2AccessValue value(val, val_type);
1635   C2ParseAccess access(this, decorators | C2_WRITE_ACCESS, bt, obj, addr);
1636   if (access.is_raw()) {
1637     return _barrier_set->BarrierSetC2::store_at(access, value);
1638   } else {
1639     return _barrier_set->store_at(access, value);
1640   }
1641 }
1642 
1643 Node* GraphKit::access_load_at(Node* obj,   // containing obj
1644                                Node* adr,   // actual address to store val at
1645                                const TypePtr* adr_type,
1646                                const Type* val_type,
1647                                BasicType bt,
1648                                DecoratorSet decorators) {
1649   if (stopped()) {
1650     return top(); // Dead path ?
1651   }
1652 
1653   C2AccessValuePtr addr(adr, adr_type);
1654   C2ParseAccess access(this, decorators | C2_READ_ACCESS, bt, obj, addr);
1655   if (access.is_raw()) {
1656     return _barrier_set->BarrierSetC2::load_at(access, val_type);
1657   } else {
1658     return _barrier_set->load_at(access, val_type);
1659   }
1660 }
1661 
1662 Node* GraphKit::access_load(Node* adr,   // actual address to load val at
1663                             const Type* val_type,
1664                             BasicType bt,
1665                             DecoratorSet decorators) {
1666   if (stopped()) {
1667     return top(); // Dead path ?
1668   }
1669 
1670   C2AccessValuePtr addr(adr, adr->bottom_type()->is_ptr());
1671   C2ParseAccess access(this, decorators | C2_READ_ACCESS, bt, nullptr, addr);
1672   if (access.is_raw()) {
1673     return _barrier_set->BarrierSetC2::load_at(access, val_type);
1674   } else {
1675     return _barrier_set->load_at(access, val_type);
1676   }
1677 }
1678 
1679 Node* GraphKit::access_atomic_cmpxchg_val_at(Node* obj,
1680                                              Node* adr,
1681                                              const TypePtr* adr_type,
1682                                              int alias_idx,
1683                                              Node* expected_val,
1684                                              Node* new_val,
1685                                              const Type* value_type,
1686                                              BasicType bt,
1687                                              DecoratorSet decorators) {
1688   C2AccessValuePtr addr(adr, adr_type);
1689   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1690                         bt, obj, addr, alias_idx);
1691   if (access.is_raw()) {
1692     return _barrier_set->BarrierSetC2::atomic_cmpxchg_val_at(access, expected_val, new_val, value_type);
1693   } else {
1694     return _barrier_set->atomic_cmpxchg_val_at(access, expected_val, new_val, value_type);
1695   }
1696 }
1697 
1698 Node* GraphKit::access_atomic_cmpxchg_bool_at(Node* obj,
1699                                               Node* adr,
1700                                               const TypePtr* adr_type,
1701                                               int alias_idx,
1702                                               Node* expected_val,
1703                                               Node* new_val,
1704                                               const Type* value_type,
1705                                               BasicType bt,
1706                                               DecoratorSet decorators) {
1707   C2AccessValuePtr addr(adr, adr_type);
1708   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1709                         bt, obj, addr, alias_idx);
1710   if (access.is_raw()) {
1711     return _barrier_set->BarrierSetC2::atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type);
1712   } else {
1713     return _barrier_set->atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type);
1714   }
1715 }
1716 
1717 Node* GraphKit::access_atomic_xchg_at(Node* obj,
1718                                       Node* adr,
1719                                       const TypePtr* adr_type,
1720                                       int alias_idx,
1721                                       Node* new_val,
1722                                       const Type* value_type,
1723                                       BasicType bt,
1724                                       DecoratorSet decorators) {
1725   C2AccessValuePtr addr(adr, adr_type);
1726   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1727                         bt, obj, addr, alias_idx);
1728   if (access.is_raw()) {
1729     return _barrier_set->BarrierSetC2::atomic_xchg_at(access, new_val, value_type);
1730   } else {
1731     return _barrier_set->atomic_xchg_at(access, new_val, value_type);
1732   }
1733 }
1734 
1735 Node* GraphKit::access_atomic_add_at(Node* obj,
1736                                      Node* adr,
1737                                      const TypePtr* adr_type,
1738                                      int alias_idx,
1739                                      Node* new_val,
1740                                      const Type* value_type,
1741                                      BasicType bt,
1742                                      DecoratorSet decorators) {
1743   C2AccessValuePtr addr(adr, adr_type);
1744   C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS, bt, obj, addr, alias_idx);
1745   if (access.is_raw()) {
1746     return _barrier_set->BarrierSetC2::atomic_add_at(access, new_val, value_type);
1747   } else {
1748     return _barrier_set->atomic_add_at(access, new_val, value_type);
1749   }
1750 }
1751 
1752 void GraphKit::access_clone(Node* src, Node* dst, Node* size, bool is_array) {
1753   return _barrier_set->clone(this, src, dst, size, is_array);
1754 }
1755 
1756 //-------------------------array_element_address-------------------------
1757 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1758                                       const TypeInt* sizetype, Node* ctrl) {
1759   uint shift  = exact_log2(type2aelembytes(elembt));
1760   uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1761 
1762   // short-circuit a common case (saves lots of confusing waste motion)
1763   jint idx_con = find_int_con(idx, -1);
1764   if (idx_con >= 0) {
1765     intptr_t offset = header + ((intptr_t)idx_con << shift);
1766     return basic_plus_adr(ary, offset);
1767   }
1768 
1769   // must be correct type for alignment purposes
1770   Node* base  = basic_plus_adr(ary, header);
1771   idx = Compile::conv_I2X_index(&_gvn, idx, sizetype, ctrl);
1772   Node* scale = _gvn.transform( new LShiftXNode(idx, intcon(shift)) );
1773   return basic_plus_adr(ary, base, scale);
1774 }
1775 
1776 //-------------------------load_array_element-------------------------
1777 Node* GraphKit::load_array_element(Node* ary, Node* idx, const TypeAryPtr* arytype, bool set_ctrl) {
1778   const Type* elemtype = arytype->elem();
1779   BasicType elembt = elemtype->array_element_basic_type();
1780   Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1781   if (elembt == T_NARROWOOP) {
1782     elembt = T_OBJECT; // To satisfy switch in LoadNode::make()
1783   }
1784   Node* ld = access_load_at(ary, adr, arytype, elemtype, elembt,
1785                             IN_HEAP | IS_ARRAY | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0));
1786   return ld;
1787 }
1788 
1789 //-------------------------set_arguments_for_java_call-------------------------
1790 // Arguments (pre-popped from the stack) are taken from the JVMS.
1791 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1792   // Add the call arguments:
1793   uint nargs = call->method()->arg_size();
1794   for (uint i = 0; i < nargs; i++) {
1795     Node* arg = argument(i);
1796     call->init_req(i + TypeFunc::Parms, arg);
1797   }
1798 }
1799 
1800 //---------------------------set_edges_for_java_call---------------------------
1801 // Connect a newly created call into the current JVMS.
1802 // A return value node (if any) is returned from set_edges_for_java_call.
1803 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1804 
1805   // Add the predefined inputs:
1806   call->init_req( TypeFunc::Control, control() );
1807   call->init_req( TypeFunc::I_O    , i_o() );
1808   call->init_req( TypeFunc::Memory , reset_memory() );
1809   call->init_req( TypeFunc::FramePtr, frameptr() );
1810   call->init_req( TypeFunc::ReturnAdr, top() );
1811 
1812   add_safepoint_edges(call, must_throw);
1813 
1814   Node* xcall = _gvn.transform(call);
1815 
1816   if (xcall == top()) {
1817     set_control(top());
1818     return;
1819   }
1820   assert(xcall == call, "call identity is stable");
1821 
1822   // Re-use the current map to produce the result.
1823 
1824   set_control(_gvn.transform(new ProjNode(call, TypeFunc::Control)));
1825   set_i_o(    _gvn.transform(new ProjNode(call, TypeFunc::I_O    , separate_io_proj)));
1826   set_all_memory_call(xcall, separate_io_proj);
1827 
1828   //return xcall;   // no need, caller already has it
1829 }
1830 
1831 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj, bool deoptimize) {
1832   if (stopped())  return top();  // maybe the call folded up?
1833 
1834   // Capture the return value, if any.
1835   Node* ret;
1836   if (call->method() == nullptr ||
1837       call->method()->return_type()->basic_type() == T_VOID)
1838         ret = top();
1839   else  ret = _gvn.transform(new ProjNode(call, TypeFunc::Parms));
1840 
1841   // Note:  Since any out-of-line call can produce an exception,
1842   // we always insert an I_O projection from the call into the result.
1843 
1844   make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj, deoptimize);
1845 
1846   if (separate_io_proj) {
1847     // The caller requested separate projections be used by the fall
1848     // through and exceptional paths, so replace the projections for
1849     // the fall through path.
1850     set_i_o(_gvn.transform( new ProjNode(call, TypeFunc::I_O) ));
1851     set_all_memory(_gvn.transform( new ProjNode(call, TypeFunc::Memory) ));
1852   }
1853   return ret;
1854 }
1855 
1856 //--------------------set_predefined_input_for_runtime_call--------------------
1857 // Reading and setting the memory state is way conservative here.
1858 // The real problem is that I am not doing real Type analysis on memory,
1859 // so I cannot distinguish card mark stores from other stores.  Across a GC
1860 // point the Store Barrier and the card mark memory has to agree.  I cannot
1861 // have a card mark store and its barrier split across the GC point from
1862 // either above or below.  Here I get that to happen by reading ALL of memory.
1863 // A better answer would be to separate out card marks from other memory.
1864 // For now, return the input memory state, so that it can be reused
1865 // after the call, if this call has restricted memory effects.
1866 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call, Node* narrow_mem) {
1867   // Set fixed predefined input arguments
1868   Node* memory = reset_memory();
1869   Node* m = narrow_mem == nullptr ? memory : narrow_mem;
1870   call->init_req( TypeFunc::Control,   control()  );
1871   call->init_req( TypeFunc::I_O,       top()      ); // does no i/o
1872   call->init_req( TypeFunc::Memory,    m          ); // may gc ptrs
1873   call->init_req( TypeFunc::FramePtr,  frameptr() );
1874   call->init_req( TypeFunc::ReturnAdr, top()      );
1875   return memory;
1876 }
1877 
1878 //-------------------set_predefined_output_for_runtime_call--------------------
1879 // Set control and memory (not i_o) from the call.
1880 // If keep_mem is not null, use it for the output state,
1881 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1882 // If hook_mem is null, this call produces no memory effects at all.
1883 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1884 // then only that memory slice is taken from the call.
1885 // In the last case, we must put an appropriate memory barrier before
1886 // the call, so as to create the correct anti-dependencies on loads
1887 // preceding the call.
1888 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1889                                                       Node* keep_mem,
1890                                                       const TypePtr* hook_mem) {
1891   // no i/o
1892   set_control(_gvn.transform( new ProjNode(call,TypeFunc::Control) ));
1893   if (keep_mem) {
1894     // First clone the existing memory state
1895     set_all_memory(keep_mem);
1896     if (hook_mem != nullptr) {
1897       // Make memory for the call
1898       Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
1899       // Set the RawPtr memory state only.  This covers all the heap top/GC stuff
1900       // We also use hook_mem to extract specific effects from arraycopy stubs.
1901       set_memory(mem, hook_mem);
1902     }
1903     // ...else the call has NO memory effects.
1904 
1905     // Make sure the call advertises its memory effects precisely.
1906     // This lets us build accurate anti-dependences in gcm.cpp.
1907     assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1908            "call node must be constructed correctly");
1909   } else {
1910     assert(hook_mem == nullptr, "");
1911     // This is not a "slow path" call; all memory comes from the call.
1912     set_all_memory_call(call);
1913   }
1914 }
1915 
1916 // Keep track of MergeMems feeding into other MergeMems
1917 static void add_mergemem_users_to_worklist(Unique_Node_List& wl, Node* mem) {
1918   if (!mem->is_MergeMem()) {
1919     return;
1920   }
1921   for (SimpleDUIterator i(mem); i.has_next(); i.next()) {
1922     Node* use = i.get();
1923     if (use->is_MergeMem()) {
1924       wl.push(use);
1925     }
1926   }
1927 }
1928 
1929 // Replace the call with the current state of the kit.
1930 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes, bool do_asserts) {
1931   JVMState* ejvms = nullptr;
1932   if (has_exceptions()) {
1933     ejvms = transfer_exceptions_into_jvms();
1934   }
1935 
1936   ReplacedNodes replaced_nodes = map()->replaced_nodes();
1937   ReplacedNodes replaced_nodes_exception;
1938   Node* ex_ctl = top();
1939 
1940   SafePointNode* final_state = stop();
1941 
1942   // Find all the needed outputs of this call
1943   CallProjections callprojs;
1944   call->extract_projections(&callprojs, true, do_asserts);
1945 
1946   Unique_Node_List wl;
1947   Node* init_mem = call->in(TypeFunc::Memory);
1948   Node* final_mem = final_state->in(TypeFunc::Memory);
1949   Node* final_ctl = final_state->in(TypeFunc::Control);
1950   Node* final_io = final_state->in(TypeFunc::I_O);
1951 
1952   // Replace all the old call edges with the edges from the inlining result
1953   if (callprojs.fallthrough_catchproj != nullptr) {
1954     C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
1955   }
1956   if (callprojs.fallthrough_memproj != nullptr) {
1957     if (final_mem->is_MergeMem()) {
1958       // Parser's exits MergeMem was not transformed but may be optimized
1959       final_mem = _gvn.transform(final_mem);
1960     }
1961     C->gvn_replace_by(callprojs.fallthrough_memproj,   final_mem);
1962     add_mergemem_users_to_worklist(wl, final_mem);
1963   }
1964   if (callprojs.fallthrough_ioproj != nullptr) {
1965     C->gvn_replace_by(callprojs.fallthrough_ioproj,    final_io);
1966   }
1967 
1968   // Replace the result with the new result if it exists and is used
1969   if (callprojs.resproj != nullptr && result != nullptr) {
1970     C->gvn_replace_by(callprojs.resproj, result);
1971   }
1972 
1973   if (ejvms == nullptr) {
1974     // No exception edges to simply kill off those paths
1975     if (callprojs.catchall_catchproj != nullptr) {
1976       C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1977     }
1978     if (callprojs.catchall_memproj != nullptr) {
1979       C->gvn_replace_by(callprojs.catchall_memproj,   C->top());
1980     }
1981     if (callprojs.catchall_ioproj != nullptr) {
1982       C->gvn_replace_by(callprojs.catchall_ioproj,    C->top());
1983     }
1984     // Replace the old exception object with top
1985     if (callprojs.exobj != nullptr) {
1986       C->gvn_replace_by(callprojs.exobj, C->top());
1987     }
1988   } else {
1989     GraphKit ekit(ejvms);
1990 
1991     // Load my combined exception state into the kit, with all phis transformed:
1992     SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1993     replaced_nodes_exception = ex_map->replaced_nodes();
1994 
1995     Node* ex_oop = ekit.use_exception_state(ex_map);
1996 
1997     if (callprojs.catchall_catchproj != nullptr) {
1998       C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1999       ex_ctl = ekit.control();
2000     }
2001     if (callprojs.catchall_memproj != nullptr) {
2002       Node* ex_mem = ekit.reset_memory();
2003       C->gvn_replace_by(callprojs.catchall_memproj,   ex_mem);
2004       add_mergemem_users_to_worklist(wl, ex_mem);
2005     }
2006     if (callprojs.catchall_ioproj != nullptr) {
2007       C->gvn_replace_by(callprojs.catchall_ioproj,    ekit.i_o());
2008     }
2009 
2010     // Replace the old exception object with the newly created one
2011     if (callprojs.exobj != nullptr) {
2012       C->gvn_replace_by(callprojs.exobj, ex_oop);
2013     }
2014   }
2015 
2016   // Disconnect the call from the graph
2017   call->disconnect_inputs(C);
2018   C->gvn_replace_by(call, C->top());
2019 
2020   // Clean up any MergeMems that feed other MergeMems since the
2021   // optimizer doesn't like that.
2022   while (wl.size() > 0) {
2023     _gvn.transform(wl.pop());
2024   }
2025 
2026   if (callprojs.fallthrough_catchproj != nullptr && !final_ctl->is_top() && do_replaced_nodes) {
2027     replaced_nodes.apply(C, final_ctl);
2028   }
2029   if (!ex_ctl->is_top() && do_replaced_nodes) {
2030     replaced_nodes_exception.apply(C, ex_ctl);
2031   }
2032 }
2033 
2034 
2035 //------------------------------increment_counter------------------------------
2036 // for statistics: increment a VM counter by 1
2037 
2038 void GraphKit::increment_counter(address counter_addr) {
2039   Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
2040   increment_counter(adr1);
2041 }
2042 
2043 void GraphKit::increment_counter(Node* counter_addr) {
2044   Node* ctrl = control();
2045   Node* cnt  = make_load(ctrl, counter_addr, TypeLong::LONG, T_LONG, MemNode::unordered);
2046   Node* incr = _gvn.transform(new AddLNode(cnt, _gvn.longcon(1)));
2047   store_to_memory(ctrl, counter_addr, incr, T_LONG, MemNode::unordered);
2048 }
2049 
2050 
2051 //------------------------------uncommon_trap----------------------------------
2052 // Bail out to the interpreter in mid-method.  Implemented by calling the
2053 // uncommon_trap blob.  This helper function inserts a runtime call with the
2054 // right debug info.
2055 Node* GraphKit::uncommon_trap(int trap_request,
2056                              ciKlass* klass, const char* comment,
2057                              bool must_throw,
2058                              bool keep_exact_action) {
2059   if (failing_internal()) {
2060     stop();
2061   }
2062   if (stopped())  return nullptr; // trap reachable?
2063 
2064   // Note:  If ProfileTraps is true, and if a deopt. actually
2065   // occurs here, the runtime will make sure an MDO exists.  There is
2066   // no need to call method()->ensure_method_data() at this point.
2067 
2068   // Set the stack pointer to the right value for reexecution:
2069   set_sp(reexecute_sp());
2070 
2071 #ifdef ASSERT
2072   if (!must_throw) {
2073     // Make sure the stack has at least enough depth to execute
2074     // the current bytecode.
2075     int inputs, ignored_depth;
2076     if (compute_stack_effects(inputs, ignored_depth)) {
2077       assert(sp() >= inputs, "must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
2078              Bytecodes::name(java_bc()), sp(), inputs);
2079     }
2080   }
2081 #endif
2082 
2083   Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
2084   Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
2085 
2086   switch (action) {
2087   case Deoptimization::Action_maybe_recompile:
2088   case Deoptimization::Action_reinterpret:
2089     // Temporary fix for 6529811 to allow virtual calls to be sure they
2090     // get the chance to go from mono->bi->mega
2091     if (!keep_exact_action &&
2092         Deoptimization::trap_request_index(trap_request) < 0 &&
2093         too_many_recompiles(reason)) {
2094       // This BCI is causing too many recompilations.
2095       if (C->log() != nullptr) {
2096         C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'",
2097                 Deoptimization::trap_reason_name(reason),
2098                 Deoptimization::trap_action_name(action));
2099       }
2100       action = Deoptimization::Action_none;
2101       trap_request = Deoptimization::make_trap_request(reason, action);
2102     } else {
2103       C->set_trap_can_recompile(true);
2104     }
2105     break;
2106   case Deoptimization::Action_make_not_entrant:
2107     C->set_trap_can_recompile(true);
2108     break;
2109   case Deoptimization::Action_none:
2110   case Deoptimization::Action_make_not_compilable:
2111     break;
2112   default:
2113 #ifdef ASSERT
2114     fatal("unknown action %d: %s", action, Deoptimization::trap_action_name(action));
2115 #endif
2116     break;
2117   }
2118 
2119   if (TraceOptoParse) {
2120     char buf[100];
2121     tty->print_cr("Uncommon trap %s at bci:%d",
2122                   Deoptimization::format_trap_request(buf, sizeof(buf),
2123                                                       trap_request), bci());
2124   }
2125 
2126   CompileLog* log = C->log();
2127   if (log != nullptr) {
2128     int kid = (klass == nullptr)? -1: log->identify(klass);
2129     log->begin_elem("uncommon_trap bci='%d'", bci());
2130     char buf[100];
2131     log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2132                                                           trap_request));
2133     if (kid >= 0)         log->print(" klass='%d'", kid);
2134     if (comment != nullptr)  log->print(" comment='%s'", comment);
2135     log->end_elem();
2136   }
2137 
2138   // Make sure any guarding test views this path as very unlikely
2139   Node *i0 = control()->in(0);
2140   if (i0 != nullptr && i0->is_If()) {        // Found a guarding if test?
2141     IfNode *iff = i0->as_If();
2142     float f = iff->_prob;   // Get prob
2143     if (control()->Opcode() == Op_IfTrue) {
2144       if (f > PROB_UNLIKELY_MAG(4))
2145         iff->_prob = PROB_MIN;
2146     } else {
2147       if (f < PROB_LIKELY_MAG(4))
2148         iff->_prob = PROB_MAX;
2149     }
2150   }
2151 
2152   // Clear out dead values from the debug info.
2153   kill_dead_locals();
2154 
2155   // Now insert the uncommon trap subroutine call
2156   address call_addr = OptoRuntime::uncommon_trap_blob()->entry_point();
2157   const TypePtr* no_memory_effects = nullptr;
2158   // Pass the index of the class to be loaded
2159   Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2160                                  (must_throw ? RC_MUST_THROW : 0),
2161                                  OptoRuntime::uncommon_trap_Type(),
2162                                  call_addr, "uncommon_trap", no_memory_effects,
2163                                  intcon(trap_request));
2164   assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2165          "must extract request correctly from the graph");
2166   assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2167 
2168   call->set_req(TypeFunc::ReturnAdr, returnadr());
2169   // The debug info is the only real input to this call.
2170 
2171   // Halt-and-catch fire here.  The above call should never return!
2172   HaltNode* halt = new HaltNode(control(), frameptr(), "uncommon trap returned which should never happen"
2173                                                        PRODUCT_ONLY(COMMA /*reachable*/false));
2174   _gvn.set_type_bottom(halt);
2175   root()->add_req(halt);
2176 
2177   stop_and_kill_map();
2178   return call;
2179 }
2180 
2181 
2182 //--------------------------just_allocated_object------------------------------
2183 // Report the object that was just allocated.
2184 // It must be the case that there are no intervening safepoints.
2185 // We use this to determine if an object is so "fresh" that
2186 // it does not require card marks.
2187 Node* GraphKit::just_allocated_object(Node* current_control) {
2188   Node* ctrl = current_control;
2189   // Object::<init> is invoked after allocation, most of invoke nodes
2190   // will be reduced, but a region node is kept in parse time, we check
2191   // the pattern and skip the region node if it degraded to a copy.
2192   if (ctrl != nullptr && ctrl->is_Region() && ctrl->req() == 2 &&
2193       ctrl->as_Region()->is_copy()) {
2194     ctrl = ctrl->as_Region()->is_copy();
2195   }
2196   if (C->recent_alloc_ctl() == ctrl) {
2197    return C->recent_alloc_obj();
2198   }
2199   return nullptr;
2200 }
2201 
2202 
2203 /**
2204  * Record profiling data exact_kls for Node n with the type system so
2205  * that it can propagate it (speculation)
2206  *
2207  * @param n          node that the type applies to
2208  * @param exact_kls  type from profiling
2209  * @param maybe_null did profiling see null?
2210  *
2211  * @return           node with improved type
2212  */
2213 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind) {
2214   const Type* current_type = _gvn.type(n);
2215   assert(UseTypeSpeculation, "type speculation must be on");
2216 
2217   const TypePtr* speculative = current_type->speculative();
2218 
2219   // Should the klass from the profile be recorded in the speculative type?
2220   if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2221     const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls, Type::trust_interfaces);
2222     const TypeOopPtr* xtype = tklass->as_instance_type();
2223     assert(xtype->klass_is_exact(), "Should be exact");
2224     // Any reason to believe n is not null (from this profiling or a previous one)?
2225     assert(ptr_kind != ProfileAlwaysNull, "impossible here");
2226     const TypePtr* ptr = (ptr_kind == ProfileMaybeNull && current_type->speculative_maybe_null()) ? TypePtr::BOTTOM : TypePtr::NOTNULL;
2227     // record the new speculative type's depth
2228     speculative = xtype->cast_to_ptr_type(ptr->ptr())->is_ptr();
2229     speculative = speculative->with_inline_depth(jvms()->depth());
2230   } else if (current_type->would_improve_ptr(ptr_kind)) {
2231     // Profiling report that null was never seen so we can change the
2232     // speculative type to non null ptr.
2233     if (ptr_kind == ProfileAlwaysNull) {
2234       speculative = TypePtr::NULL_PTR;
2235     } else {
2236       assert(ptr_kind == ProfileNeverNull, "nothing else is an improvement");
2237       const TypePtr* ptr = TypePtr::NOTNULL;
2238       if (speculative != nullptr) {
2239         speculative = speculative->cast_to_ptr_type(ptr->ptr())->is_ptr();
2240       } else {
2241         speculative = ptr;
2242       }
2243     }
2244   }
2245 
2246   if (speculative != current_type->speculative()) {
2247     // Build a type with a speculative type (what we think we know
2248     // about the type but will need a guard when we use it)
2249     const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2250     // We're changing the type, we need a new CheckCast node to carry
2251     // the new type. The new type depends on the control: what
2252     // profiling tells us is only valid from here as far as we can
2253     // tell.
2254     Node* cast = new CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2255     cast = _gvn.transform(cast);
2256     replace_in_map(n, cast);
2257     n = cast;
2258   }
2259 
2260   return n;
2261 }
2262 
2263 /**
2264  * Record profiling data from receiver profiling at an invoke with the
2265  * type system so that it can propagate it (speculation)
2266  *
2267  * @param n  receiver node
2268  *
2269  * @return   node with improved type
2270  */
2271 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2272   if (!UseTypeSpeculation) {
2273     return n;
2274   }
2275   ciKlass* exact_kls = profile_has_unique_klass();
2276   ProfilePtrKind ptr_kind = ProfileMaybeNull;
2277   if ((java_bc() == Bytecodes::_checkcast ||
2278        java_bc() == Bytecodes::_instanceof ||
2279        java_bc() == Bytecodes::_aastore) &&
2280       method()->method_data()->is_mature()) {
2281     ciProfileData* data = method()->method_data()->bci_to_data(bci());
2282     if (data != nullptr) {
2283       if (!data->as_BitData()->null_seen()) {
2284         ptr_kind = ProfileNeverNull;
2285       } else {
2286         assert(data->is_ReceiverTypeData(), "bad profile data type");
2287         ciReceiverTypeData* call = (ciReceiverTypeData*)data->as_ReceiverTypeData();
2288         uint i = 0;
2289         for (; i < call->row_limit(); i++) {
2290           ciKlass* receiver = call->receiver(i);
2291           if (receiver != nullptr) {
2292             break;
2293           }
2294         }
2295         ptr_kind = (i == call->row_limit()) ? ProfileAlwaysNull : ProfileMaybeNull;
2296       }
2297     }
2298   }
2299   return record_profile_for_speculation(n, exact_kls, ptr_kind);
2300 }
2301 
2302 /**
2303  * Record profiling data from argument profiling at an invoke with the
2304  * type system so that it can propagate it (speculation)
2305  *
2306  * @param dest_method  target method for the call
2307  * @param bc           what invoke bytecode is this?
2308  */
2309 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2310   if (!UseTypeSpeculation) {
2311     return;
2312   }
2313   const TypeFunc* tf    = TypeFunc::make(dest_method);
2314   int             nargs = tf->domain()->cnt() - TypeFunc::Parms;
2315   int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2316   for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2317     const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2318     if (is_reference_type(targ->basic_type())) {
2319       ProfilePtrKind ptr_kind = ProfileMaybeNull;
2320       ciKlass* better_type = nullptr;
2321       if (method()->argument_profiled_type(bci(), i, better_type, ptr_kind)) {
2322         record_profile_for_speculation(argument(j), better_type, ptr_kind);
2323       }
2324       i++;
2325     }
2326   }
2327 }
2328 
2329 /**
2330  * Record profiling data from parameter profiling at an invoke with
2331  * the type system so that it can propagate it (speculation)
2332  */
2333 void GraphKit::record_profiled_parameters_for_speculation() {
2334   if (!UseTypeSpeculation) {
2335     return;
2336   }
2337   for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2338     if (_gvn.type(local(i))->isa_oopptr()) {
2339       ProfilePtrKind ptr_kind = ProfileMaybeNull;
2340       ciKlass* better_type = nullptr;
2341       if (method()->parameter_profiled_type(j, better_type, ptr_kind)) {
2342         record_profile_for_speculation(local(i), better_type, ptr_kind);
2343       }
2344       j++;
2345     }
2346   }
2347 }
2348 
2349 /**
2350  * Record profiling data from return value profiling at an invoke with
2351  * the type system so that it can propagate it (speculation)
2352  */
2353 void GraphKit::record_profiled_return_for_speculation() {
2354   if (!UseTypeSpeculation) {
2355     return;
2356   }
2357   ProfilePtrKind ptr_kind = ProfileMaybeNull;
2358   ciKlass* better_type = nullptr;
2359   if (method()->return_profiled_type(bci(), better_type, ptr_kind)) {
2360     // If profiling reports a single type for the return value,
2361     // feed it to the type system so it can propagate it as a
2362     // speculative type
2363     record_profile_for_speculation(stack(sp()-1), better_type, ptr_kind);
2364   }
2365 }
2366 
2367 void GraphKit::round_double_arguments(ciMethod* dest_method) {
2368   if (Matcher::strict_fp_requires_explicit_rounding) {
2369     // (Note:  TypeFunc::make has a cache that makes this fast.)
2370     const TypeFunc* tf    = TypeFunc::make(dest_method);
2371     int             nargs = tf->domain()->cnt() - TypeFunc::Parms;
2372     for (int j = 0; j < nargs; j++) {
2373       const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2374       if (targ->basic_type() == T_DOUBLE) {
2375         // If any parameters are doubles, they must be rounded before
2376         // the call, dprecision_rounding does gvn.transform
2377         Node *arg = argument(j);
2378         arg = dprecision_rounding(arg);
2379         set_argument(j, arg);
2380       }
2381     }
2382   }
2383 }
2384 
2385 // rounding for strict float precision conformance
2386 Node* GraphKit::precision_rounding(Node* n) {
2387   if (Matcher::strict_fp_requires_explicit_rounding) {
2388 #ifdef IA32
2389     if (UseSSE == 0) {
2390       return _gvn.transform(new RoundFloatNode(nullptr, n));
2391     }
2392 #else
2393     Unimplemented();
2394 #endif // IA32
2395   }
2396   return n;
2397 }
2398 
2399 // rounding for strict double precision conformance
2400 Node* GraphKit::dprecision_rounding(Node *n) {
2401   if (Matcher::strict_fp_requires_explicit_rounding) {
2402 #ifdef IA32
2403     if (UseSSE < 2) {
2404       return _gvn.transform(new RoundDoubleNode(nullptr, n));
2405     }
2406 #else
2407     Unimplemented();
2408 #endif // IA32
2409   }
2410   return n;
2411 }
2412 
2413 //=============================================================================
2414 // Generate a fast path/slow path idiom.  Graph looks like:
2415 // [foo] indicates that 'foo' is a parameter
2416 //
2417 //              [in]     null
2418 //                 \    /
2419 //                  CmpP
2420 //                  Bool ne
2421 //                   If
2422 //                  /  \
2423 //              True    False-<2>
2424 //              / |
2425 //             /  cast_not_null
2426 //           Load  |    |   ^
2427 //        [fast_test]   |   |
2428 // gvn to   opt_test    |   |
2429 //          /    \      |  <1>
2430 //      True     False  |
2431 //        |         \\  |
2432 //   [slow_call]     \[fast_result]
2433 //    Ctl   Val       \      \
2434 //     |               \      \
2435 //    Catch       <1>   \      \
2436 //   /    \        ^     \      \
2437 //  Ex    No_Ex    |      \      \
2438 //  |       \   \  |       \ <2>  \
2439 //  ...      \  [slow_res] |  |    \   [null_result]
2440 //            \         \--+--+---  |  |
2441 //             \           | /    \ | /
2442 //              --------Region     Phi
2443 //
2444 //=============================================================================
2445 // Code is structured as a series of driver functions all called 'do_XXX' that
2446 // call a set of helper functions.  Helper functions first, then drivers.
2447 
2448 //------------------------------null_check_oop---------------------------------
2449 // Null check oop.  Set null-path control into Region in slot 3.
2450 // Make a cast-not-nullness use the other not-null control.  Return cast.
2451 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2452                                bool never_see_null,
2453                                bool safe_for_replace,
2454                                bool speculative) {
2455   // Initial null check taken path
2456   (*null_control) = top();
2457   Node* cast = null_check_common(value, T_OBJECT, false, null_control, speculative);
2458 
2459   // Generate uncommon_trap:
2460   if (never_see_null && (*null_control) != top()) {
2461     // If we see an unexpected null at a check-cast we record it and force a
2462     // recompile; the offending check-cast will be compiled to handle nulls.
2463     // If we see more than one offending BCI, then all checkcasts in the
2464     // method will be compiled to handle nulls.
2465     PreserveJVMState pjvms(this);
2466     set_control(*null_control);
2467     replace_in_map(value, null());
2468     Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculative);
2469     uncommon_trap(reason,
2470                   Deoptimization::Action_make_not_entrant);
2471     (*null_control) = top();    // null path is dead
2472   }
2473   if ((*null_control) == top() && safe_for_replace) {
2474     replace_in_map(value, cast);
2475   }
2476 
2477   // Cast away null-ness on the result
2478   return cast;
2479 }
2480 
2481 //------------------------------opt_iff----------------------------------------
2482 // Optimize the fast-check IfNode.  Set the fast-path region slot 2.
2483 // Return slow-path control.
2484 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2485   IfNode *opt_iff = _gvn.transform(iff)->as_If();
2486 
2487   // Fast path taken; set region slot 2
2488   Node *fast_taken = _gvn.transform( new IfFalseNode(opt_iff) );
2489   region->init_req(2,fast_taken); // Capture fast-control
2490 
2491   // Fast path not-taken, i.e. slow path
2492   Node *slow_taken = _gvn.transform( new IfTrueNode(opt_iff) );
2493   return slow_taken;
2494 }
2495 
2496 //-----------------------------make_runtime_call-------------------------------
2497 Node* GraphKit::make_runtime_call(int flags,
2498                                   const TypeFunc* call_type, address call_addr,
2499                                   const char* call_name,
2500                                   const TypePtr* adr_type,
2501                                   // The following parms are all optional.
2502                                   // The first null ends the list.
2503                                   Node* parm0, Node* parm1,
2504                                   Node* parm2, Node* parm3,
2505                                   Node* parm4, Node* parm5,
2506                                   Node* parm6, Node* parm7) {
2507   assert(call_addr != nullptr, "must not call null targets");
2508 
2509   // Slow-path call
2510   bool is_leaf = !(flags & RC_NO_LEAF);
2511   bool has_io  = (!is_leaf && !(flags & RC_NO_IO));
2512   if (call_name == nullptr) {
2513     assert(!is_leaf, "must supply name for leaf");
2514     call_name = OptoRuntime::stub_name(call_addr);
2515   }
2516   CallNode* call;
2517   if (!is_leaf) {
2518     call = new CallStaticJavaNode(call_type, call_addr, call_name, adr_type);
2519   } else if (flags & RC_NO_FP) {
2520     call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2521   } else  if (flags & RC_VECTOR){
2522     uint num_bits = call_type->range()->field_at(TypeFunc::Parms)->is_vect()->length_in_bytes() * BitsPerByte;
2523     call = new CallLeafVectorNode(call_type, call_addr, call_name, adr_type, num_bits);
2524   } else {
2525     call = new CallLeafNode(call_type, call_addr, call_name, adr_type);
2526   }
2527 
2528   // The following is similar to set_edges_for_java_call,
2529   // except that the memory effects of the call are restricted to AliasIdxRaw.
2530 
2531   // Slow path call has no side-effects, uses few values
2532   bool wide_in  = !(flags & RC_NARROW_MEM);
2533   bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2534 
2535   Node* prev_mem = nullptr;
2536   if (wide_in) {
2537     prev_mem = set_predefined_input_for_runtime_call(call);
2538   } else {
2539     assert(!wide_out, "narrow in => narrow out");
2540     Node* narrow_mem = memory(adr_type);
2541     prev_mem = set_predefined_input_for_runtime_call(call, narrow_mem);
2542   }
2543 
2544   // Hook each parm in order.  Stop looking at the first null.
2545   if (parm0 != nullptr) { call->init_req(TypeFunc::Parms+0, parm0);
2546   if (parm1 != nullptr) { call->init_req(TypeFunc::Parms+1, parm1);
2547   if (parm2 != nullptr) { call->init_req(TypeFunc::Parms+2, parm2);
2548   if (parm3 != nullptr) { call->init_req(TypeFunc::Parms+3, parm3);
2549   if (parm4 != nullptr) { call->init_req(TypeFunc::Parms+4, parm4);
2550   if (parm5 != nullptr) { call->init_req(TypeFunc::Parms+5, parm5);
2551   if (parm6 != nullptr) { call->init_req(TypeFunc::Parms+6, parm6);
2552   if (parm7 != nullptr) { call->init_req(TypeFunc::Parms+7, parm7);
2553   /* close each nested if ===> */  } } } } } } } }
2554   assert(call->in(call->req()-1) != nullptr, "must initialize all parms");
2555 
2556   if (!is_leaf) {
2557     // Non-leaves can block and take safepoints:
2558     add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2559   }
2560   // Non-leaves can throw exceptions:
2561   if (has_io) {
2562     call->set_req(TypeFunc::I_O, i_o());
2563   }
2564 
2565   if (flags & RC_UNCOMMON) {
2566     // Set the count to a tiny probability.  Cf. Estimate_Block_Frequency.
2567     // (An "if" probability corresponds roughly to an unconditional count.
2568     // Sort of.)
2569     call->set_cnt(PROB_UNLIKELY_MAG(4));
2570   }
2571 
2572   Node* c = _gvn.transform(call);
2573   assert(c == call, "cannot disappear");
2574 
2575   if (wide_out) {
2576     // Slow path call has full side-effects.
2577     set_predefined_output_for_runtime_call(call);
2578   } else {
2579     // Slow path call has few side-effects, and/or sets few values.
2580     set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2581   }
2582 
2583   if (has_io) {
2584     set_i_o(_gvn.transform(new ProjNode(call, TypeFunc::I_O)));
2585   }
2586   return call;
2587 
2588 }
2589 
2590 // i2b
2591 Node* GraphKit::sign_extend_byte(Node* in) {
2592   Node* tmp = _gvn.transform(new LShiftINode(in, _gvn.intcon(24)));
2593   return _gvn.transform(new RShiftINode(tmp, _gvn.intcon(24)));
2594 }
2595 
2596 // i2s
2597 Node* GraphKit::sign_extend_short(Node* in) {
2598   Node* tmp = _gvn.transform(new LShiftINode(in, _gvn.intcon(16)));
2599   return _gvn.transform(new RShiftINode(tmp, _gvn.intcon(16)));
2600 }
2601 
2602 //------------------------------merge_memory-----------------------------------
2603 // Merge memory from one path into the current memory state.
2604 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2605   for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2606     Node* old_slice = mms.force_memory();
2607     Node* new_slice = mms.memory2();
2608     if (old_slice != new_slice) {
2609       PhiNode* phi;
2610       if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) {
2611         if (mms.is_empty()) {
2612           // clone base memory Phi's inputs for this memory slice
2613           assert(old_slice == mms.base_memory(), "sanity");
2614           phi = PhiNode::make(region, nullptr, Type::MEMORY, mms.adr_type(C));
2615           _gvn.set_type(phi, Type::MEMORY);
2616           for (uint i = 1; i < phi->req(); i++) {
2617             phi->init_req(i, old_slice->in(i));
2618           }
2619         } else {
2620           phi = old_slice->as_Phi(); // Phi was generated already
2621         }
2622       } else {
2623         phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2624         _gvn.set_type(phi, Type::MEMORY);
2625       }
2626       phi->set_req(new_path, new_slice);
2627       mms.set_memory(phi);
2628     }
2629   }
2630 }
2631 
2632 //------------------------------make_slow_call_ex------------------------------
2633 // Make the exception handler hookups for the slow call
2634 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) {
2635   if (stopped())  return;
2636 
2637   // Make a catch node with just two handlers:  fall-through and catch-all
2638   Node* i_o  = _gvn.transform( new ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2639   Node* catc = _gvn.transform( new CatchNode(control(), i_o, 2) );
2640   Node* norm = new CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci);
2641   _gvn.set_type_bottom(norm);
2642   C->record_for_igvn(norm);
2643   Node* excp = _gvn.transform( new CatchProjNode(catc, CatchProjNode::catch_all_index,    CatchProjNode::no_handler_bci) );
2644 
2645   { PreserveJVMState pjvms(this);
2646     set_control(excp);
2647     set_i_o(i_o);
2648 
2649     if (excp != top()) {
2650       if (deoptimize) {
2651         // Deoptimize if an exception is caught. Don't construct exception state in this case.
2652         uncommon_trap(Deoptimization::Reason_unhandled,
2653                       Deoptimization::Action_none);
2654       } else {
2655         // Create an exception state also.
2656         // Use an exact type if the caller has a specific exception.
2657         const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2658         Node*       ex_oop  = new CreateExNode(ex_type, control(), i_o);
2659         add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2660       }
2661     }
2662   }
2663 
2664   // Get the no-exception control from the CatchNode.
2665   set_control(norm);
2666 }
2667 
2668 static IfNode* gen_subtype_check_compare(Node* ctrl, Node* in1, Node* in2, BoolTest::mask test, float p, PhaseGVN& gvn, BasicType bt) {
2669   Node* cmp = nullptr;
2670   switch(bt) {
2671   case T_INT: cmp = new CmpINode(in1, in2); break;
2672   case T_ADDRESS: cmp = new CmpPNode(in1, in2); break;
2673   default: fatal("unexpected comparison type %s", type2name(bt));
2674   }
2675   cmp = gvn.transform(cmp);
2676   Node* bol = gvn.transform(new BoolNode(cmp, test));
2677   IfNode* iff = new IfNode(ctrl, bol, p, COUNT_UNKNOWN);
2678   gvn.transform(iff);
2679   if (!bol->is_Con()) gvn.record_for_igvn(iff);
2680   return iff;
2681 }
2682 
2683 //-------------------------------gen_subtype_check-----------------------------
2684 // Generate a subtyping check.  Takes as input the subtype and supertype.
2685 // Returns 2 values: sets the default control() to the true path and returns
2686 // the false path.  Only reads invariant memory; sets no (visible) memory.
2687 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2688 // but that's not exposed to the optimizer.  This call also doesn't take in an
2689 // Object; if you wish to check an Object you need to load the Object's class
2690 // prior to coming here.
2691 Node* Phase::gen_subtype_check(Node* subklass, Node* superklass, Node** ctrl, Node* mem, PhaseGVN& gvn,
2692                                ciMethod* method, int bci) {
2693   Compile* C = gvn.C;
2694   if ((*ctrl)->is_top()) {
2695     return C->top();
2696   }
2697 
2698   // Fast check for identical types, perhaps identical constants.
2699   // The types can even be identical non-constants, in cases
2700   // involving Array.newInstance, Object.clone, etc.
2701   if (subklass == superklass)
2702     return C->top();             // false path is dead; no test needed.
2703 
2704   if (gvn.type(superklass)->singleton()) {
2705     const TypeKlassPtr* superk = gvn.type(superklass)->is_klassptr();
2706     const TypeKlassPtr* subk   = gvn.type(subklass)->is_klassptr();
2707 
2708     // In the common case of an exact superklass, try to fold up the
2709     // test before generating code.  You may ask, why not just generate
2710     // the code and then let it fold up?  The answer is that the generated
2711     // code will necessarily include null checks, which do not always
2712     // completely fold away.  If they are also needless, then they turn
2713     // into a performance loss.  Example:
2714     //    Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2715     // Here, the type of 'fa' is often exact, so the store check
2716     // of fa[1]=x will fold up, without testing the nullness of x.
2717     //
2718     // At macro expansion, we would have already folded the SubTypeCheckNode
2719     // being expanded here because we always perform the static sub type
2720     // check in SubTypeCheckNode::sub() regardless of whether
2721     // StressReflectiveCode is set or not. We can therefore skip this
2722     // static check when StressReflectiveCode is on.
2723     switch (C->static_subtype_check(superk, subk)) {
2724     case Compile::SSC_always_false:
2725       {
2726         Node* always_fail = *ctrl;
2727         *ctrl = gvn.C->top();
2728         return always_fail;
2729       }
2730     case Compile::SSC_always_true:
2731       return C->top();
2732     case Compile::SSC_easy_test:
2733       {
2734         // Just do a direct pointer compare and be done.
2735         IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_STATIC_FREQUENT, gvn, T_ADDRESS);
2736         *ctrl = gvn.transform(new IfTrueNode(iff));
2737         return gvn.transform(new IfFalseNode(iff));
2738       }
2739     case Compile::SSC_full_test:
2740       break;
2741     default:
2742       ShouldNotReachHere();
2743     }
2744   }
2745 
2746   // %%% Possible further optimization:  Even if the superklass is not exact,
2747   // if the subklass is the unique subtype of the superklass, the check
2748   // will always succeed.  We could leave a dependency behind to ensure this.
2749 
2750   // First load the super-klass's check-offset
2751   Node *p1 = gvn.transform(new AddPNode(superklass, superklass, gvn.MakeConX(in_bytes(Klass::super_check_offset_offset()))));
2752   Node* m = C->immutable_memory();
2753   Node *chk_off = gvn.transform(new LoadINode(nullptr, m, p1, gvn.type(p1)->is_ptr(), TypeInt::INT, MemNode::unordered));
2754   int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2755   const TypeInt* chk_off_t = chk_off->Value(&gvn)->isa_int();
2756   int chk_off_con = (chk_off_t != nullptr && chk_off_t->is_con()) ? chk_off_t->get_con() : cacheoff_con;
2757   bool might_be_cache = (chk_off_con == cacheoff_con);
2758 
2759   // Load from the sub-klass's super-class display list, or a 1-word cache of
2760   // the secondary superclass list, or a failing value with a sentinel offset
2761   // if the super-klass is an interface or exceptionally deep in the Java
2762   // hierarchy and we have to scan the secondary superclass list the hard way.
2763   // Worst-case type is a little odd: null is allowed as a result (usually
2764   // klass loads can never produce a null).
2765   Node *chk_off_X = chk_off;
2766 #ifdef _LP64
2767   chk_off_X = gvn.transform(new ConvI2LNode(chk_off_X));
2768 #endif
2769   Node *p2 = gvn.transform(new AddPNode(subklass,subklass,chk_off_X));
2770   // For some types like interfaces the following loadKlass is from a 1-word
2771   // cache which is mutable so can't use immutable memory.  Other
2772   // types load from the super-class display table which is immutable.
2773   Node *kmem = C->immutable_memory();
2774   // secondary_super_cache is not immutable but can be treated as such because:
2775   // - no ideal node writes to it in a way that could cause an
2776   //   incorrect/missed optimization of the following Load.
2777   // - it's a cache so, worse case, not reading the latest value
2778   //   wouldn't cause incorrect execution
2779   if (might_be_cache && mem != nullptr) {
2780     kmem = mem->is_MergeMem() ? mem->as_MergeMem()->memory_at(C->get_alias_index(gvn.type(p2)->is_ptr())) : mem;
2781   }
2782   Node* nkls = gvn.transform(LoadKlassNode::make(gvn, kmem, p2, gvn.type(p2)->is_ptr(), TypeInstKlassPtr::OBJECT_OR_NULL));
2783 
2784   // Compile speed common case: ARE a subtype and we canNOT fail
2785   if (superklass == nkls) {
2786     return C->top();             // false path is dead; no test needed.
2787   }
2788 
2789   // Gather the various success & failures here
2790   RegionNode* r_not_subtype = new RegionNode(3);
2791   gvn.record_for_igvn(r_not_subtype);
2792   RegionNode* r_ok_subtype = new RegionNode(4);
2793   gvn.record_for_igvn(r_ok_subtype);
2794 
2795   // If we might perform an expensive check, first try to take advantage of profile data that was attached to the
2796   // SubTypeCheck node
2797   if (might_be_cache && method != nullptr && VM_Version::profile_all_receivers_at_type_check()) {
2798     ciCallProfile profile = method->call_profile_at_bci(bci);
2799     float total_prob = 0;
2800     for (int i = 0; profile.has_receiver(i); ++i) {
2801       float prob = profile.receiver_prob(i);
2802       total_prob += prob;
2803     }
2804     if (total_prob * 100. >= TypeProfileSubTypeCheckCommonThreshold) {
2805       const TypeKlassPtr* superk = gvn.type(superklass)->is_klassptr();
2806       for (int i = 0; profile.has_receiver(i); ++i) {
2807         ciKlass* klass = profile.receiver(i);
2808         const TypeKlassPtr* klass_t = TypeKlassPtr::make(klass);
2809         Compile::SubTypeCheckResult result = C->static_subtype_check(superk, klass_t);
2810         if (result != Compile::SSC_always_true && result != Compile::SSC_always_false) {
2811           continue;
2812         }
2813         float prob = profile.receiver_prob(i);
2814         ConNode* klass_node = gvn.makecon(klass_t);
2815         IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, klass_node, BoolTest::eq, prob, gvn, T_ADDRESS);
2816         Node* iftrue = gvn.transform(new IfTrueNode(iff));
2817 
2818         if (result == Compile::SSC_always_true) {
2819           r_ok_subtype->add_req(iftrue);
2820         } else {
2821           assert(result == Compile::SSC_always_false, "");
2822           r_not_subtype->add_req(iftrue);
2823         }
2824         *ctrl = gvn.transform(new IfFalseNode(iff));
2825       }
2826     }
2827   }
2828 
2829   // See if we get an immediate positive hit.  Happens roughly 83% of the
2830   // time.  Test to see if the value loaded just previously from the subklass
2831   // is exactly the superklass.
2832   IfNode *iff1 = gen_subtype_check_compare(*ctrl, superklass, nkls, BoolTest::eq, PROB_LIKELY(0.83f), gvn, T_ADDRESS);
2833   Node *iftrue1 = gvn.transform( new IfTrueNode (iff1));
2834   *ctrl = gvn.transform(new IfFalseNode(iff1));
2835 
2836   // Compile speed common case: Check for being deterministic right now.  If
2837   // chk_off is a constant and not equal to cacheoff then we are NOT a
2838   // subklass.  In this case we need exactly the 1 test above and we can
2839   // return those results immediately.
2840   if (!might_be_cache) {
2841     Node* not_subtype_ctrl = *ctrl;
2842     *ctrl = iftrue1; // We need exactly the 1 test above
2843     PhaseIterGVN* igvn = gvn.is_IterGVN();
2844     if (igvn != nullptr) {
2845       igvn->remove_globally_dead_node(r_ok_subtype);
2846       igvn->remove_globally_dead_node(r_not_subtype);
2847     }
2848     return not_subtype_ctrl;
2849   }
2850 
2851   r_ok_subtype->init_req(1, iftrue1);
2852 
2853   // Check for immediate negative hit.  Happens roughly 11% of the time (which
2854   // is roughly 63% of the remaining cases).  Test to see if the loaded
2855   // check-offset points into the subklass display list or the 1-element
2856   // cache.  If it points to the display (and NOT the cache) and the display
2857   // missed then it's not a subtype.
2858   Node *cacheoff = gvn.intcon(cacheoff_con);
2859   IfNode *iff2 = gen_subtype_check_compare(*ctrl, chk_off, cacheoff, BoolTest::ne, PROB_LIKELY(0.63f), gvn, T_INT);
2860   r_not_subtype->init_req(1, gvn.transform(new IfTrueNode (iff2)));
2861   *ctrl = gvn.transform(new IfFalseNode(iff2));
2862 
2863   // Check for self.  Very rare to get here, but it is taken 1/3 the time.
2864   // No performance impact (too rare) but allows sharing of secondary arrays
2865   // which has some footprint reduction.
2866   IfNode *iff3 = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_LIKELY(0.36f), gvn, T_ADDRESS);
2867   r_ok_subtype->init_req(2, gvn.transform(new IfTrueNode(iff3)));
2868   *ctrl = gvn.transform(new IfFalseNode(iff3));
2869 
2870   // -- Roads not taken here: --
2871   // We could also have chosen to perform the self-check at the beginning
2872   // of this code sequence, as the assembler does.  This would not pay off
2873   // the same way, since the optimizer, unlike the assembler, can perform
2874   // static type analysis to fold away many successful self-checks.
2875   // Non-foldable self checks work better here in second position, because
2876   // the initial primary superclass check subsumes a self-check for most
2877   // types.  An exception would be a secondary type like array-of-interface,
2878   // which does not appear in its own primary supertype display.
2879   // Finally, we could have chosen to move the self-check into the
2880   // PartialSubtypeCheckNode, and from there out-of-line in a platform
2881   // dependent manner.  But it is worthwhile to have the check here,
2882   // where it can be perhaps be optimized.  The cost in code space is
2883   // small (register compare, branch).
2884 
2885   // Now do a linear scan of the secondary super-klass array.  Again, no real
2886   // performance impact (too rare) but it's gotta be done.
2887   // Since the code is rarely used, there is no penalty for moving it
2888   // out of line, and it can only improve I-cache density.
2889   // The decision to inline or out-of-line this final check is platform
2890   // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2891   Node* psc = gvn.transform(
2892     new PartialSubtypeCheckNode(*ctrl, subklass, superklass));
2893 
2894   IfNode *iff4 = gen_subtype_check_compare(*ctrl, psc, gvn.zerocon(T_OBJECT), BoolTest::ne, PROB_FAIR, gvn, T_ADDRESS);
2895   r_not_subtype->init_req(2, gvn.transform(new IfTrueNode (iff4)));
2896   r_ok_subtype ->init_req(3, gvn.transform(new IfFalseNode(iff4)));
2897 
2898   // Return false path; set default control to true path.
2899   *ctrl = gvn.transform(r_ok_subtype);
2900   return gvn.transform(r_not_subtype);
2901 }
2902 
2903 Node* GraphKit::gen_subtype_check(Node* obj_or_subklass, Node* superklass) {
2904   bool expand_subtype_check = C->post_loop_opts_phase(); // macro node expansion is over
2905   if (expand_subtype_check) {
2906     MergeMemNode* mem = merged_memory();
2907     Node* ctrl = control();
2908     Node* subklass = obj_or_subklass;
2909     if (!_gvn.type(obj_or_subklass)->isa_klassptr()) {
2910       subklass = load_object_klass(obj_or_subklass);
2911     }
2912 
2913     Node* n = Phase::gen_subtype_check(subklass, superklass, &ctrl, mem, _gvn, method(), bci());
2914     set_control(ctrl);
2915     return n;
2916   }
2917 
2918   Node* check = _gvn.transform(new SubTypeCheckNode(C, obj_or_subklass, superklass, method(), bci()));
2919   Node* bol = _gvn.transform(new BoolNode(check, BoolTest::eq));
2920   IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN);
2921   set_control(_gvn.transform(new IfTrueNode(iff)));
2922   return _gvn.transform(new IfFalseNode(iff));
2923 }
2924 
2925 // Profile-driven exact type check:
2926 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2927                                     float prob,
2928                                     Node* *casted_receiver) {
2929   assert(!klass->is_interface(), "no exact type check on interfaces");
2930 
2931   const TypeKlassPtr* tklass = TypeKlassPtr::make(klass, Type::trust_interfaces);
2932   Node* recv_klass = load_object_klass(receiver);
2933   Node* want_klass = makecon(tklass);
2934   Node* cmp = _gvn.transform(new CmpPNode(recv_klass, want_klass));
2935   Node* bol = _gvn.transform(new BoolNode(cmp, BoolTest::eq));
2936   IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2937   set_control( _gvn.transform(new IfTrueNode (iff)));
2938   Node* fail = _gvn.transform(new IfFalseNode(iff));
2939 
2940   if (!stopped()) {
2941     const TypeOopPtr* receiver_type = _gvn.type(receiver)->isa_oopptr();
2942     const TypeOopPtr* recvx_type = tklass->as_instance_type();
2943     assert(recvx_type->klass_is_exact(), "");
2944 
2945     if (!receiver_type->higher_equal(recvx_type)) { // ignore redundant casts
2946       // Subsume downstream occurrences of receiver with a cast to
2947       // recv_xtype, since now we know what the type will be.
2948       Node* cast = new CheckCastPPNode(control(), receiver, recvx_type);
2949       (*casted_receiver) = _gvn.transform(cast);
2950       assert(!(*casted_receiver)->is_top(), "that path should be unreachable");
2951       // (User must make the replace_in_map call.)
2952     }
2953   }
2954 
2955   return fail;
2956 }
2957 
2958 //------------------------------subtype_check_receiver-------------------------
2959 Node* GraphKit::subtype_check_receiver(Node* receiver, ciKlass* klass,
2960                                        Node** casted_receiver) {
2961   const TypeKlassPtr* tklass = TypeKlassPtr::make(klass, Type::trust_interfaces)->try_improve();
2962   Node* want_klass = makecon(tklass);
2963 
2964   Node* slow_ctl = gen_subtype_check(receiver, want_klass);
2965 
2966   // Ignore interface type information until interface types are properly tracked.
2967   if (!stopped() && !klass->is_interface()) {
2968     const TypeOopPtr* receiver_type = _gvn.type(receiver)->isa_oopptr();
2969     const TypeOopPtr* recv_type = tklass->cast_to_exactness(false)->is_klassptr()->as_instance_type();
2970     if (!receiver_type->higher_equal(recv_type)) { // ignore redundant casts
2971       Node* cast = new CheckCastPPNode(control(), receiver, recv_type);
2972       (*casted_receiver) = _gvn.transform(cast);
2973     }
2974   }
2975 
2976   return slow_ctl;
2977 }
2978 
2979 //------------------------------seems_never_null-------------------------------
2980 // Use null_seen information if it is available from the profile.
2981 // If we see an unexpected null at a type check we record it and force a
2982 // recompile; the offending check will be recompiled to handle nulls.
2983 // If we see several offending BCIs, then all checks in the
2984 // method will be recompiled.
2985 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data, bool& speculating) {
2986   speculating = !_gvn.type(obj)->speculative_maybe_null();
2987   Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculating);
2988   if (UncommonNullCast               // Cutout for this technique
2989       && obj != null()               // And not the -Xcomp stupid case?
2990       && !too_many_traps(reason)
2991       ) {
2992     if (speculating) {
2993       return true;
2994     }
2995     if (data == nullptr)
2996       // Edge case:  no mature data.  Be optimistic here.
2997       return true;
2998     // If the profile has not seen a null, assume it won't happen.
2999     assert(java_bc() == Bytecodes::_checkcast ||
3000            java_bc() == Bytecodes::_instanceof ||
3001            java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
3002     return !data->as_BitData()->null_seen();
3003   }
3004   speculating = false;
3005   return false;
3006 }
3007 
3008 void GraphKit::guard_klass_is_initialized(Node* klass) {
3009   assert(ClassInitBarrierMode > 0, "no barriers");
3010   int init_state_off = in_bytes(InstanceKlass::init_state_offset());
3011   Node* adr = basic_plus_adr(top(), klass, init_state_off);
3012   Node* init_state = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3013                                     adr->bottom_type()->is_ptr(), TypeInt::BYTE,
3014                                     T_BYTE, MemNode::unordered);
3015   init_state = _gvn.transform(init_state);
3016 
3017   Node* initialized_state = makecon(TypeInt::make(InstanceKlass::fully_initialized));
3018 
3019   Node* chk = _gvn.transform(new CmpINode(initialized_state, init_state));
3020   Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3021 
3022   switch (ClassInitBarrierMode) {
3023     case 1: { // uncommon trap on slow path
3024       BuildCutout unless(this, tst, PROB_MAX);
3025       // Do not deoptimize this nmethod. Go to Interpreter to initialize class.
3026       uncommon_trap(Deoptimization::Reason_uninitialized, Deoptimization::Action_none);
3027       break;
3028     }
3029     case 2: { // runtime call on slow path
3030       if (StressClassInitBarriers) {
3031         tst = makecon(TypeInt::ZERO); // always go through slow path
3032       }
3033       IfNode* iff = create_and_xform_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
3034 //    IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
3035 
3036       RegionNode* r = new RegionNode(3);
3037       r->init_req(1, _gvn.transform(new IfTrueNode(iff)));
3038 
3039       set_control(_gvn.transform(new IfFalseNode(iff)));
3040 
3041       if (!stopped()) {
3042         kill_dead_locals();
3043 
3044         Node* call = make_runtime_call(RC_NO_LEAF,
3045                                        OptoRuntime::class_init_barrier_Type(),
3046                                        OptoRuntime::class_init_barrier_Java(),
3047                                        nullptr, TypePtr::BOTTOM,
3048                                        klass);
3049         // Deoptimization during class init barrier execution should trigger current bytecode reexecution.
3050         call->jvms()->set_should_reexecute(true);
3051 
3052         // FIXME: deoptimize for now. deoptimize=false doesn't work with late inlining yet.
3053         // Parse::create_entry_map() introduces a barrier which uses distinct JVM state (*before* call).
3054         // Compilation fails when distinct exception states are combined.
3055         make_slow_call_ex(call, env()->Throwable_klass(), /*separate_io_proj=*/true, /*deoptimize=*/true);
3056 
3057         Node* fast_io  = call->in(TypeFunc::I_O);
3058         Node* fast_mem = call->in(TypeFunc::Memory);
3059         // These two phis are pre-filled with copies of of the fast IO and Memory
3060         Node* io_phi   = PhiNode::make(r, fast_io,  Type::ABIO);
3061         Node* mem_phi  = PhiNode::make(r, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
3062 
3063         r->init_req(2, control());
3064         io_phi->init_req(2, i_o());
3065         mem_phi->init_req(2, reset_memory());
3066 
3067         set_all_memory(_gvn.transform(mem_phi));
3068         set_i_o(_gvn.transform(io_phi));
3069       } else {
3070         r->init_req(2, top());
3071       }
3072       set_control(_gvn.transform(r));
3073       break;
3074     }
3075 
3076     default: fatal("unknown barrier mode: %d", ClassInitBarrierMode);
3077   }
3078   C->set_has_clinit_barriers(true);
3079 }
3080 
3081 void GraphKit::guard_klass_being_initialized(Node* klass) {
3082   int init_state_off = in_bytes(InstanceKlass::init_state_offset());
3083   Node* adr = basic_plus_adr(top(), klass, init_state_off);
3084   Node* init_state = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3085                                     adr->bottom_type()->is_ptr(), TypeInt::BYTE,
3086                                     T_BYTE, MemNode::acquire);
3087   init_state = _gvn.transform(init_state);
3088 
3089   Node* being_initialized_state = makecon(TypeInt::make(InstanceKlass::being_initialized));
3090 
3091   Node* chk = _gvn.transform(new CmpINode(being_initialized_state, init_state));
3092   Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3093 
3094   { BuildCutout unless(this, tst, PROB_MAX);
3095     uncommon_trap(Deoptimization::Reason_initialized, Deoptimization::Action_reinterpret);
3096   }
3097 }
3098 
3099 void GraphKit::guard_init_thread(Node* klass) {
3100   int init_thread_off = in_bytes(InstanceKlass::init_thread_offset());
3101   Node* adr = basic_plus_adr(top(), klass, init_thread_off);
3102 
3103   Node* init_thread = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3104                                      adr->bottom_type()->is_ptr(), TypePtr::NOTNULL,
3105                                      T_ADDRESS, MemNode::unordered);
3106   init_thread = _gvn.transform(init_thread);
3107 
3108   Node* cur_thread = _gvn.transform(new ThreadLocalNode());
3109 
3110   Node* chk = _gvn.transform(new CmpPNode(cur_thread, init_thread));
3111   Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3112 
3113   { BuildCutout unless(this, tst, PROB_MAX);
3114     uncommon_trap(Deoptimization::Reason_uninitialized, Deoptimization::Action_none);
3115   }
3116 }
3117 
3118 void GraphKit::clinit_barrier(ciInstanceKlass* ik, ciMethod* context) {
3119   if (C->do_clinit_barriers()) {
3120     Node* klass = makecon(TypeKlassPtr::make(ik, Type::trust_interfaces));
3121     guard_klass_is_initialized(klass);
3122     return;
3123   }
3124   if (ik->is_being_initialized()) {
3125     if (C->needs_clinit_barrier(ik, context)) {
3126       Node* klass = makecon(TypeKlassPtr::make(ik, Type::trust_interfaces));
3127       guard_klass_being_initialized(klass);
3128       guard_init_thread(klass);
3129       insert_mem_bar(Op_MemBarCPUOrder);
3130     }
3131   } else if (ik->is_initialized()) {
3132     return; // no barrier needed
3133   } else {
3134     uncommon_trap(Deoptimization::Reason_uninitialized,
3135                   Deoptimization::Action_reinterpret,
3136                   nullptr);
3137   }
3138 }
3139 
3140 //------------------------maybe_cast_profiled_receiver-------------------------
3141 // If the profile has seen exactly one type, narrow to exactly that type.
3142 // Subsequent type checks will always fold up.
3143 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
3144                                              const TypeKlassPtr* require_klass,
3145                                              ciKlass* spec_klass,
3146                                              bool safe_for_replace) {
3147   if (!UseTypeProfile || !TypeProfileCasts) return nullptr;
3148 
3149   Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != nullptr);
3150 
3151   // Make sure we haven't already deoptimized from this tactic.
3152   if (too_many_traps_or_recompiles(reason))
3153     return nullptr;
3154 
3155   // (No, this isn't a call, but it's enough like a virtual call
3156   // to use the same ciMethod accessor to get the profile info...)
3157   // If we have a speculative type use it instead of profiling (which
3158   // may not help us)
3159   ciKlass* exact_kls = spec_klass == nullptr ? profile_has_unique_klass() : spec_klass;
3160   if (exact_kls != nullptr) {// no cast failures here
3161     if (require_klass == nullptr ||
3162         C->static_subtype_check(require_klass, TypeKlassPtr::make(exact_kls, Type::trust_interfaces)) == Compile::SSC_always_true) {
3163       // If we narrow the type to match what the type profile sees or
3164       // the speculative type, we can then remove the rest of the
3165       // cast.
3166       // This is a win, even if the exact_kls is very specific,
3167       // because downstream operations, such as method calls,
3168       // will often benefit from the sharper type.
3169       Node* exact_obj = not_null_obj; // will get updated in place...
3170       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
3171                                             &exact_obj);
3172       { PreserveJVMState pjvms(this);
3173         set_control(slow_ctl);
3174         uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile);
3175       }
3176       if (safe_for_replace) {
3177         replace_in_map(not_null_obj, exact_obj);
3178       }
3179       return exact_obj;
3180     }
3181     // assert(ssc == Compile::SSC_always_true)... except maybe the profile lied to us.
3182   }
3183 
3184   return nullptr;
3185 }
3186 
3187 /**
3188  * Cast obj to type and emit guard unless we had too many traps here
3189  * already
3190  *
3191  * @param obj       node being casted
3192  * @param type      type to cast the node to
3193  * @param not_null  true if we know node cannot be null
3194  */
3195 Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
3196                                         ciKlass* type,
3197                                         bool not_null) {
3198   if (stopped()) {
3199     return obj;
3200   }
3201 
3202   // type is null if profiling tells us this object is always null
3203   if (type != nullptr) {
3204     Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
3205     Deoptimization::DeoptReason null_reason = Deoptimization::Reason_speculate_null_check;
3206 
3207     if (!too_many_traps_or_recompiles(null_reason) &&
3208         !too_many_traps_or_recompiles(class_reason)) {
3209       Node* not_null_obj = nullptr;
3210       // not_null is true if we know the object is not null and
3211       // there's no need for a null check
3212       if (!not_null) {
3213         Node* null_ctl = top();
3214         not_null_obj = null_check_oop(obj, &null_ctl, true, true, true);
3215         assert(null_ctl->is_top(), "no null control here");
3216       } else {
3217         not_null_obj = obj;
3218       }
3219 
3220       Node* exact_obj = not_null_obj;
3221       ciKlass* exact_kls = type;
3222       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
3223                                             &exact_obj);
3224       {
3225         PreserveJVMState pjvms(this);
3226         set_control(slow_ctl);
3227         uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile);
3228       }
3229       replace_in_map(not_null_obj, exact_obj);
3230       obj = exact_obj;
3231     }
3232   } else {
3233     if (!too_many_traps_or_recompiles(Deoptimization::Reason_null_assert)) {
3234       Node* exact_obj = null_assert(obj);
3235       replace_in_map(obj, exact_obj);
3236       obj = exact_obj;
3237     }
3238   }
3239   return obj;
3240 }
3241 
3242 //-------------------------------gen_instanceof--------------------------------
3243 // Generate an instance-of idiom.  Used by both the instance-of bytecode
3244 // and the reflective instance-of call.
3245 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
3246   kill_dead_locals();           // Benefit all the uncommon traps
3247   assert( !stopped(), "dead parse path should be checked in callers" );
3248   assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
3249          "must check for not-null not-dead klass in callers");
3250 
3251   // Make the merge point
3252   enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
3253   RegionNode* region = new RegionNode(PATH_LIMIT);
3254   Node*       phi    = new PhiNode(region, TypeInt::BOOL);
3255   C->set_has_split_ifs(true); // Has chance for split-if optimization
3256 
3257   ciProfileData* data = nullptr;
3258   if (java_bc() == Bytecodes::_instanceof) {  // Only for the bytecode
3259     data = method()->method_data()->bci_to_data(bci());
3260   }
3261   bool speculative_not_null = false;
3262   bool never_see_null = (ProfileDynamicTypes  // aggressive use of profile
3263                          && seems_never_null(obj, data, speculative_not_null));
3264 
3265   // Null check; get casted pointer; set region slot 3
3266   Node* null_ctl = top();
3267   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3268 
3269   // If not_null_obj is dead, only null-path is taken
3270   if (stopped()) {              // Doing instance-of on a null?
3271     set_control(null_ctl);
3272     return intcon(0);
3273   }
3274   region->init_req(_null_path, null_ctl);
3275   phi   ->init_req(_null_path, intcon(0)); // Set null path value
3276   if (null_ctl == top()) {
3277     // Do this eagerly, so that pattern matches like is_diamond_phi
3278     // will work even during parsing.
3279     assert(_null_path == PATH_LIMIT-1, "delete last");
3280     region->del_req(_null_path);
3281     phi   ->del_req(_null_path);
3282   }
3283 
3284   // Do we know the type check always succeed?
3285   bool known_statically = false;
3286   if (_gvn.type(superklass)->singleton()) {
3287     const TypeKlassPtr* superk = _gvn.type(superklass)->is_klassptr();
3288     const TypeKlassPtr* subk = _gvn.type(obj)->is_oopptr()->as_klass_type();
3289     if (subk->is_loaded()) {
3290       int static_res = C->static_subtype_check(superk, subk);
3291       known_statically = (static_res == Compile::SSC_always_true || static_res == Compile::SSC_always_false);
3292     }
3293   }
3294 
3295   if (!known_statically) {
3296     const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3297     // We may not have profiling here or it may not help us. If we
3298     // have a speculative type use it to perform an exact cast.
3299     ciKlass* spec_obj_type = obj_type->speculative_type();
3300     if (spec_obj_type != nullptr || (ProfileDynamicTypes && data != nullptr)) {
3301       Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, nullptr, spec_obj_type, safe_for_replace);
3302       if (stopped()) {            // Profile disagrees with this path.
3303         set_control(null_ctl);    // Null is the only remaining possibility.
3304         return intcon(0);
3305       }
3306       if (cast_obj != nullptr) {
3307         not_null_obj = cast_obj;
3308       }
3309     }
3310   }
3311 
3312   // Generate the subtype check
3313   Node* not_subtype_ctrl = gen_subtype_check(not_null_obj, superklass);
3314 
3315   // Plug in the success path to the general merge in slot 1.
3316   region->init_req(_obj_path, control());
3317   phi   ->init_req(_obj_path, intcon(1));
3318 
3319   // Plug in the failing path to the general merge in slot 2.
3320   region->init_req(_fail_path, not_subtype_ctrl);
3321   phi   ->init_req(_fail_path, intcon(0));
3322 
3323   // Return final merged results
3324   set_control( _gvn.transform(region) );
3325   record_for_igvn(region);
3326 
3327   // If we know the type check always succeeds then we don't use the
3328   // profiling data at this bytecode. Don't lose it, feed it to the
3329   // type system as a speculative type.
3330   if (safe_for_replace) {
3331     Node* casted_obj = record_profiled_receiver_for_speculation(obj);
3332     replace_in_map(obj, casted_obj);
3333   }
3334 
3335   return _gvn.transform(phi);
3336 }
3337 
3338 //-------------------------------gen_checkcast---------------------------------
3339 // Generate a checkcast idiom.  Used by both the checkcast bytecode and the
3340 // array store bytecode.  Stack must be as-if BEFORE doing the bytecode so the
3341 // uncommon-trap paths work.  Adjust stack after this call.
3342 // If failure_control is supplied and not null, it is filled in with
3343 // the control edge for the cast failure.  Otherwise, an appropriate
3344 // uncommon trap or exception is thrown.
3345 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
3346                               Node* *failure_control) {
3347   kill_dead_locals();           // Benefit all the uncommon traps
3348   const TypeKlassPtr* klass_ptr_type = _gvn.type(superklass)->is_klassptr();
3349   const TypeKlassPtr* improved_klass_ptr_type = klass_ptr_type->try_improve();
3350   const TypeOopPtr* toop = improved_klass_ptr_type->cast_to_exactness(false)->as_instance_type();
3351 
3352   // Fast cutout:  Check the case that the cast is vacuously true.
3353   // This detects the common cases where the test will short-circuit
3354   // away completely.  We do this before we perform the null check,
3355   // because if the test is going to turn into zero code, we don't
3356   // want a residual null check left around.  (Causes a slowdown,
3357   // for example, in some objArray manipulations, such as a[i]=a[j].)
3358   if (improved_klass_ptr_type->singleton()) {
3359     const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
3360     if (objtp != nullptr) {
3361       switch (C->static_subtype_check(improved_klass_ptr_type, objtp->as_klass_type())) {
3362       case Compile::SSC_always_true:
3363         // If we know the type check always succeed then we don't use
3364         // the profiling data at this bytecode. Don't lose it, feed it
3365         // to the type system as a speculative type.
3366         return record_profiled_receiver_for_speculation(obj);
3367       case Compile::SSC_always_false:
3368         // It needs a null check because a null will *pass* the cast check.
3369         // A non-null value will always produce an exception.
3370         if (!objtp->maybe_null()) {
3371           bool is_aastore = (java_bc() == Bytecodes::_aastore);
3372           Deoptimization::DeoptReason reason = is_aastore ?
3373             Deoptimization::Reason_array_check : Deoptimization::Reason_class_check;
3374           builtin_throw(reason);
3375           return top();
3376         } else if (!too_many_traps_or_recompiles(Deoptimization::Reason_null_assert)) {
3377           return null_assert(obj);
3378         }
3379         break; // Fall through to full check
3380       default:
3381         break;
3382       }
3383     }
3384   }
3385 
3386   ciProfileData* data = nullptr;
3387   bool safe_for_replace = false;
3388   if (failure_control == nullptr) {        // use MDO in regular case only
3389     assert(java_bc() == Bytecodes::_aastore ||
3390            java_bc() == Bytecodes::_checkcast,
3391            "interpreter profiles type checks only for these BCs");
3392     data = method()->method_data()->bci_to_data(bci());
3393     safe_for_replace = true;
3394   }
3395 
3396   // Make the merge point
3397   enum { _obj_path = 1, _null_path, PATH_LIMIT };
3398   RegionNode* region = new RegionNode(PATH_LIMIT);
3399   Node*       phi    = new PhiNode(region, toop);
3400   C->set_has_split_ifs(true); // Has chance for split-if optimization
3401 
3402   // Use null-cast information if it is available
3403   bool speculative_not_null = false;
3404   bool never_see_null = ((failure_control == nullptr)  // regular case only
3405                          && seems_never_null(obj, data, speculative_not_null));
3406 
3407   // Null check; get casted pointer; set region slot 3
3408   Node* null_ctl = top();
3409   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3410 
3411   // If not_null_obj is dead, only null-path is taken
3412   if (stopped()) {              // Doing instance-of on a null?
3413     set_control(null_ctl);
3414     return null();
3415   }
3416   region->init_req(_null_path, null_ctl);
3417   phi   ->init_req(_null_path, null());  // Set null path value
3418   if (null_ctl == top()) {
3419     // Do this eagerly, so that pattern matches like is_diamond_phi
3420     // will work even during parsing.
3421     assert(_null_path == PATH_LIMIT-1, "delete last");
3422     region->del_req(_null_path);
3423     phi   ->del_req(_null_path);
3424   }
3425 
3426   Node* cast_obj = nullptr;
3427   if (improved_klass_ptr_type->klass_is_exact()) {
3428     // The following optimization tries to statically cast the speculative type of the object
3429     // (for example obtained during profiling) to the type of the superklass and then do a
3430     // dynamic check that the type of the object is what we expect. To work correctly
3431     // for checkcast and aastore the type of superklass should be exact.
3432     const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3433     // We may not have profiling here or it may not help us. If we have
3434     // a speculative type use it to perform an exact cast.
3435     ciKlass* spec_obj_type = obj_type->speculative_type();
3436     if (spec_obj_type != nullptr || data != nullptr) {
3437       cast_obj = maybe_cast_profiled_receiver(not_null_obj, improved_klass_ptr_type, spec_obj_type, safe_for_replace);
3438       if (cast_obj != nullptr) {
3439         if (failure_control != nullptr) // failure is now impossible
3440           (*failure_control) = top();
3441         // adjust the type of the phi to the exact klass:
3442         phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3443       }
3444     }
3445   }
3446 
3447   if (cast_obj == nullptr) {
3448     // Generate the subtype check
3449     Node* improved_superklass = superklass;
3450     if (improved_klass_ptr_type != klass_ptr_type && improved_klass_ptr_type->singleton()) {
3451       improved_superklass = makecon(improved_klass_ptr_type);
3452     }
3453     Node* not_subtype_ctrl = gen_subtype_check(not_null_obj, improved_superklass);
3454 
3455     // Plug in success path into the merge
3456     cast_obj = _gvn.transform(new CheckCastPPNode(control(), not_null_obj, toop));
3457     // Failure path ends in uncommon trap (or may be dead - failure impossible)
3458     if (failure_control == nullptr) {
3459       if (not_subtype_ctrl != top()) { // If failure is possible
3460         PreserveJVMState pjvms(this);
3461         set_control(not_subtype_ctrl);
3462         bool is_aastore = (java_bc() == Bytecodes::_aastore);
3463         Deoptimization::DeoptReason reason = is_aastore ?
3464           Deoptimization::Reason_array_check : Deoptimization::Reason_class_check;
3465         builtin_throw(reason);
3466       }
3467     } else {
3468       (*failure_control) = not_subtype_ctrl;
3469     }
3470   }
3471 
3472   region->init_req(_obj_path, control());
3473   phi   ->init_req(_obj_path, cast_obj);
3474 
3475   // A merge of null or Casted-NotNull obj
3476   Node* res = _gvn.transform(phi);
3477 
3478   // Note I do NOT always 'replace_in_map(obj,result)' here.
3479   //  if( tk->klass()->can_be_primary_super()  )
3480     // This means that if I successfully store an Object into an array-of-String
3481     // I 'forget' that the Object is really now known to be a String.  I have to
3482     // do this because we don't have true union types for interfaces - if I store
3483     // a Baz into an array-of-Interface and then tell the optimizer it's an
3484     // Interface, I forget that it's also a Baz and cannot do Baz-like field
3485     // references to it.  FIX THIS WHEN UNION TYPES APPEAR!
3486   //  replace_in_map( obj, res );
3487 
3488   // Return final merged results
3489   set_control( _gvn.transform(region) );
3490   record_for_igvn(region);
3491 
3492   return record_profiled_receiver_for_speculation(res);
3493 }
3494 
3495 //------------------------------next_monitor-----------------------------------
3496 // What number should be given to the next monitor?
3497 int GraphKit::next_monitor() {
3498   int current = jvms()->monitor_depth()* C->sync_stack_slots();
3499   int next = current + C->sync_stack_slots();
3500   // Keep the toplevel high water mark current:
3501   if (C->fixed_slots() < next)  C->set_fixed_slots(next);
3502   return current;
3503 }
3504 
3505 //------------------------------insert_mem_bar---------------------------------
3506 // Memory barrier to avoid floating things around
3507 // The membar serves as a pinch point between both control and all memory slices.
3508 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3509   MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3510   mb->init_req(TypeFunc::Control, control());
3511   mb->init_req(TypeFunc::Memory,  reset_memory());
3512   Node* membar = _gvn.transform(mb);
3513   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3514   set_all_memory_call(membar);
3515   return membar;
3516 }
3517 
3518 //-------------------------insert_mem_bar_volatile----------------------------
3519 // Memory barrier to avoid floating things around
3520 // The membar serves as a pinch point between both control and memory(alias_idx).
3521 // If you want to make a pinch point on all memory slices, do not use this
3522 // function (even with AliasIdxBot); use insert_mem_bar() instead.
3523 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3524   // When Parse::do_put_xxx updates a volatile field, it appends a series
3525   // of MemBarVolatile nodes, one for *each* volatile field alias category.
3526   // The first membar is on the same memory slice as the field store opcode.
3527   // This forces the membar to follow the store.  (Bug 6500685 broke this.)
3528   // All the other membars (for other volatile slices, including AliasIdxBot,
3529   // which stands for all unknown volatile slices) are control-dependent
3530   // on the first membar.  This prevents later volatile loads or stores
3531   // from sliding up past the just-emitted store.
3532 
3533   MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3534   mb->set_req(TypeFunc::Control,control());
3535   if (alias_idx == Compile::AliasIdxBot) {
3536     mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3537   } else {
3538     assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3539     mb->set_req(TypeFunc::Memory, memory(alias_idx));
3540   }
3541   Node* membar = _gvn.transform(mb);
3542   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3543   if (alias_idx == Compile::AliasIdxBot) {
3544     merged_memory()->set_base_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)));
3545   } else {
3546     set_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)),alias_idx);
3547   }
3548   return membar;
3549 }
3550 
3551 //------------------------------shared_lock------------------------------------
3552 // Emit locking code.
3553 FastLockNode* GraphKit::shared_lock(Node* obj) {
3554   // bci is either a monitorenter bc or InvocationEntryBci
3555   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3556   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3557 
3558   if( !GenerateSynchronizationCode )
3559     return nullptr;                // Not locking things?
3560   if (stopped())                // Dead monitor?
3561     return nullptr;
3562 
3563   assert(dead_locals_are_killed(), "should kill locals before sync. point");
3564 
3565   // Box the stack location
3566   Node* box = new BoxLockNode(next_monitor());
3567   // Check for bailout after new BoxLockNode
3568   if (failing()) { return nullptr; }
3569   box = _gvn.transform(box);
3570   Node* mem = reset_memory();
3571 
3572   FastLockNode * flock = _gvn.transform(new FastLockNode(nullptr, obj, box) )->as_FastLock();
3573 
3574   // Add monitor to debug info for the slow path.  If we block inside the
3575   // slow path and de-opt, we need the monitor hanging around
3576   map()->push_monitor( flock );
3577 
3578   const TypeFunc *tf = LockNode::lock_type();
3579   LockNode *lock = new LockNode(C, tf);
3580 
3581   lock->init_req( TypeFunc::Control, control() );
3582   lock->init_req( TypeFunc::Memory , mem );
3583   lock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
3584   lock->init_req( TypeFunc::FramePtr, frameptr() );
3585   lock->init_req( TypeFunc::ReturnAdr, top() );
3586 
3587   lock->init_req(TypeFunc::Parms + 0, obj);
3588   lock->init_req(TypeFunc::Parms + 1, box);
3589   lock->init_req(TypeFunc::Parms + 2, flock);
3590   add_safepoint_edges(lock);
3591 
3592   lock = _gvn.transform( lock )->as_Lock();
3593 
3594   // lock has no side-effects, sets few values
3595   set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3596 
3597   insert_mem_bar(Op_MemBarAcquireLock);
3598 
3599   // Add this to the worklist so that the lock can be eliminated
3600   record_for_igvn(lock);
3601 
3602 #ifndef PRODUCT
3603   if (PrintLockStatistics) {
3604     // Update the counter for this lock.  Don't bother using an atomic
3605     // operation since we don't require absolute accuracy.
3606     lock->create_lock_counter(map()->jvms());
3607     increment_counter(lock->counter()->addr());
3608   }
3609 #endif
3610 
3611   return flock;
3612 }
3613 
3614 
3615 //------------------------------shared_unlock----------------------------------
3616 // Emit unlocking code.
3617 void GraphKit::shared_unlock(Node* box, Node* obj) {
3618   // bci is either a monitorenter bc or InvocationEntryBci
3619   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3620   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3621 
3622   if( !GenerateSynchronizationCode )
3623     return;
3624   if (stopped()) {               // Dead monitor?
3625     map()->pop_monitor();        // Kill monitor from debug info
3626     return;
3627   }
3628 
3629   // Memory barrier to avoid floating things down past the locked region
3630   insert_mem_bar(Op_MemBarReleaseLock);
3631 
3632   const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3633   UnlockNode *unlock = new UnlockNode(C, tf);
3634 #ifdef ASSERT
3635   unlock->set_dbg_jvms(sync_jvms());
3636 #endif
3637   uint raw_idx = Compile::AliasIdxRaw;
3638   unlock->init_req( TypeFunc::Control, control() );
3639   unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3640   unlock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
3641   unlock->init_req( TypeFunc::FramePtr, frameptr() );
3642   unlock->init_req( TypeFunc::ReturnAdr, top() );
3643 
3644   unlock->init_req(TypeFunc::Parms + 0, obj);
3645   unlock->init_req(TypeFunc::Parms + 1, box);
3646   unlock = _gvn.transform(unlock)->as_Unlock();
3647 
3648   Node* mem = reset_memory();
3649 
3650   // unlock has no side-effects, sets few values
3651   set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3652 
3653   // Kill monitor from debug info
3654   map()->pop_monitor( );
3655 }
3656 
3657 //-------------------------------get_layout_helper-----------------------------
3658 // If the given klass is a constant or known to be an array,
3659 // fetch the constant layout helper value into constant_value
3660 // and return null.  Otherwise, load the non-constant
3661 // layout helper value, and return the node which represents it.
3662 // This two-faced routine is useful because allocation sites
3663 // almost always feature constant types.
3664 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3665   const TypeKlassPtr* klass_t = _gvn.type(klass_node)->isa_klassptr();
3666   if (!StressReflectiveCode && klass_t != nullptr) {
3667     bool xklass = klass_t->klass_is_exact();
3668     if (xklass || (klass_t->isa_aryklassptr() && klass_t->is_aryklassptr()->elem() != Type::BOTTOM)) {
3669       jint lhelper;
3670       if (klass_t->isa_aryklassptr()) {
3671         BasicType elem = klass_t->as_instance_type()->isa_aryptr()->elem()->array_element_basic_type();
3672         if (is_reference_type(elem, true)) {
3673           elem = T_OBJECT;
3674         }
3675         lhelper = Klass::array_layout_helper(elem);
3676       } else {
3677         lhelper = klass_t->is_instklassptr()->exact_klass()->layout_helper();
3678       }
3679       if (lhelper != Klass::_lh_neutral_value) {
3680         constant_value = lhelper;
3681         return (Node*) nullptr;
3682       }
3683     }
3684   }
3685   constant_value = Klass::_lh_neutral_value;  // put in a known value
3686   Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
3687   return make_load(nullptr, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3688 }
3689 
3690 // We just put in an allocate/initialize with a big raw-memory effect.
3691 // Hook selected additional alias categories on the initialization.
3692 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3693                                 MergeMemNode* init_in_merge,
3694                                 Node* init_out_raw) {
3695   DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3696   assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3697 
3698   Node* prevmem = kit.memory(alias_idx);
3699   init_in_merge->set_memory_at(alias_idx, prevmem);
3700   kit.set_memory(init_out_raw, alias_idx);
3701 }
3702 
3703 //---------------------------set_output_for_allocation-------------------------
3704 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3705                                           const TypeOopPtr* oop_type,
3706                                           bool deoptimize_on_exception) {
3707   int rawidx = Compile::AliasIdxRaw;
3708   alloc->set_req( TypeFunc::FramePtr, frameptr() );
3709   add_safepoint_edges(alloc);
3710   Node* allocx = _gvn.transform(alloc);
3711   set_control( _gvn.transform(new ProjNode(allocx, TypeFunc::Control) ) );
3712   // create memory projection for i_o
3713   set_memory ( _gvn.transform( new ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3714   make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception);
3715 
3716   // create a memory projection as for the normal control path
3717   Node* malloc = _gvn.transform(new ProjNode(allocx, TypeFunc::Memory));
3718   set_memory(malloc, rawidx);
3719 
3720   // a normal slow-call doesn't change i_o, but an allocation does
3721   // we create a separate i_o projection for the normal control path
3722   set_i_o(_gvn.transform( new ProjNode(allocx, TypeFunc::I_O, false) ) );
3723   Node* rawoop = _gvn.transform( new ProjNode(allocx, TypeFunc::Parms) );
3724 
3725   // put in an initialization barrier
3726   InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3727                                                  rawoop)->as_Initialize();
3728   assert(alloc->initialization() == init,  "2-way macro link must work");
3729   assert(init ->allocation()     == alloc, "2-way macro link must work");
3730   {
3731     // Extract memory strands which may participate in the new object's
3732     // initialization, and source them from the new InitializeNode.
3733     // This will allow us to observe initializations when they occur,
3734     // and link them properly (as a group) to the InitializeNode.
3735     assert(init->in(InitializeNode::Memory) == malloc, "");
3736     MergeMemNode* minit_in = MergeMemNode::make(malloc);
3737     init->set_req(InitializeNode::Memory, minit_in);
3738     record_for_igvn(minit_in); // fold it up later, if possible
3739     Node* minit_out = memory(rawidx);
3740     assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3741     // Add an edge in the MergeMem for the header fields so an access
3742     // to one of those has correct memory state
3743     set_memory(minit_out, C->get_alias_index(oop_type->add_offset(oopDesc::mark_offset_in_bytes())));
3744     set_memory(minit_out, C->get_alias_index(oop_type->add_offset(oopDesc::klass_offset_in_bytes())));
3745     if (oop_type->isa_aryptr()) {
3746       const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3747       int            elemidx  = C->get_alias_index(telemref);
3748       hook_memory_on_init(*this, elemidx, minit_in, minit_out);
3749     } else if (oop_type->isa_instptr()) {
3750       ciInstanceKlass* ik = oop_type->is_instptr()->instance_klass();
3751       for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3752         ciField* field = ik->nonstatic_field_at(i);
3753         if (field->offset_in_bytes() >= TrackedInitializationLimit * HeapWordSize)
3754           continue;  // do not bother to track really large numbers of fields
3755         // Find (or create) the alias category for this field:
3756         int fieldidx = C->alias_type(field)->index();
3757         hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3758       }
3759     }
3760   }
3761 
3762   // Cast raw oop to the real thing...
3763   Node* javaoop = new CheckCastPPNode(control(), rawoop, oop_type);
3764   javaoop = _gvn.transform(javaoop);
3765   C->set_recent_alloc(control(), javaoop);
3766   assert(just_allocated_object(control()) == javaoop, "just allocated");
3767 
3768 #ifdef ASSERT
3769   { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3770     assert(AllocateNode::Ideal_allocation(rawoop) == alloc,
3771            "Ideal_allocation works");
3772     assert(AllocateNode::Ideal_allocation(javaoop) == alloc,
3773            "Ideal_allocation works");
3774     if (alloc->is_AllocateArray()) {
3775       assert(AllocateArrayNode::Ideal_array_allocation(rawoop) == alloc->as_AllocateArray(),
3776              "Ideal_allocation works");
3777       assert(AllocateArrayNode::Ideal_array_allocation(javaoop) == alloc->as_AllocateArray(),
3778              "Ideal_allocation works");
3779     } else {
3780       assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3781     }
3782   }
3783 #endif //ASSERT
3784 
3785   return javaoop;
3786 }
3787 
3788 //---------------------------new_instance--------------------------------------
3789 // This routine takes a klass_node which may be constant (for a static type)
3790 // or may be non-constant (for reflective code).  It will work equally well
3791 // for either, and the graph will fold nicely if the optimizer later reduces
3792 // the type to a constant.
3793 // The optional arguments are for specialized use by intrinsics:
3794 //  - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3795 //  - If 'return_size_val', report the total object size to the caller.
3796 //  - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3797 Node* GraphKit::new_instance(Node* klass_node,
3798                              Node* extra_slow_test,
3799                              Node* *return_size_val,
3800                              bool deoptimize_on_exception) {
3801   // Compute size in doublewords
3802   // The size is always an integral number of doublewords, represented
3803   // as a positive bytewise size stored in the klass's layout_helper.
3804   // The layout_helper also encodes (in a low bit) the need for a slow path.
3805   jint  layout_con = Klass::_lh_neutral_value;
3806   Node* layout_val = get_layout_helper(klass_node, layout_con);
3807   int   layout_is_con = (layout_val == nullptr);
3808 
3809   if (extra_slow_test == nullptr)  extra_slow_test = intcon(0);
3810   // Generate the initial go-slow test.  It's either ALWAYS (return a
3811   // Node for 1) or NEVER (return a null) or perhaps (in the reflective
3812   // case) a computed value derived from the layout_helper.
3813   Node* initial_slow_test = nullptr;
3814   if (layout_is_con) {
3815     assert(!StressReflectiveCode, "stress mode does not use these paths");
3816     bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3817     initial_slow_test = must_go_slow ? intcon(1) : extra_slow_test;
3818   } else {   // reflective case
3819     // This reflective path is used by Unsafe.allocateInstance.
3820     // (It may be stress-tested by specifying StressReflectiveCode.)
3821     // Basically, we want to get into the VM is there's an illegal argument.
3822     Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3823     initial_slow_test = _gvn.transform( new AndINode(layout_val, bit) );
3824     if (extra_slow_test != intcon(0)) {
3825       initial_slow_test = _gvn.transform( new OrINode(initial_slow_test, extra_slow_test) );
3826     }
3827     // (Macro-expander will further convert this to a Bool, if necessary.)
3828   }
3829 
3830   // Find the size in bytes.  This is easy; it's the layout_helper.
3831   // The size value must be valid even if the slow path is taken.
3832   Node* size = nullptr;
3833   if (layout_is_con) {
3834     size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3835   } else {   // reflective case
3836     // This reflective path is used by clone and Unsafe.allocateInstance.
3837     size = ConvI2X(layout_val);
3838 
3839     // Clear the low bits to extract layout_helper_size_in_bytes:
3840     assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3841     Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3842     size = _gvn.transform( new AndXNode(size, mask) );
3843   }
3844   if (return_size_val != nullptr) {
3845     (*return_size_val) = size;
3846   }
3847 
3848   // This is a precise notnull oop of the klass.
3849   // (Actually, it need not be precise if this is a reflective allocation.)
3850   // It's what we cast the result to.
3851   const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3852   if (!tklass)  tklass = TypeInstKlassPtr::OBJECT;
3853   const TypeOopPtr* oop_type = tklass->as_instance_type();
3854 
3855   // Now generate allocation code
3856 
3857   // The entire memory state is needed for slow path of the allocation
3858   // since GC and deoptimization can happened.
3859   Node *mem = reset_memory();
3860   set_all_memory(mem); // Create new memory state
3861 
3862   AllocateNode* alloc = new AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3863                                          control(), mem, i_o(),
3864                                          size, klass_node,
3865                                          initial_slow_test);
3866 
3867   return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception);
3868 }
3869 
3870 //-------------------------------new_array-------------------------------------
3871 // helper for both newarray and anewarray
3872 // The 'length' parameter is (obviously) the length of the array.
3873 // The optional arguments are for specialized use by intrinsics:
3874 //  - If 'return_size_val', report the non-padded array size (sum of header size
3875 //    and array body) to the caller.
3876 //  - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3877 Node* GraphKit::new_array(Node* klass_node,     // array klass (maybe variable)
3878                           Node* length,         // number of array elements
3879                           int   nargs,          // number of arguments to push back for uncommon trap
3880                           Node* *return_size_val,
3881                           bool deoptimize_on_exception) {
3882   jint  layout_con = Klass::_lh_neutral_value;
3883   Node* layout_val = get_layout_helper(klass_node, layout_con);
3884   int   layout_is_con = (layout_val == nullptr);
3885 
3886   if (!layout_is_con && !StressReflectiveCode &&
3887       !too_many_traps(Deoptimization::Reason_class_check)) {
3888     // This is a reflective array creation site.
3889     // Optimistically assume that it is a subtype of Object[],
3890     // so that we can fold up all the address arithmetic.
3891     layout_con = Klass::array_layout_helper(T_OBJECT);
3892     Node* cmp_lh = _gvn.transform( new CmpINode(layout_val, intcon(layout_con)) );
3893     Node* bol_lh = _gvn.transform( new BoolNode(cmp_lh, BoolTest::eq) );
3894     { BuildCutout unless(this, bol_lh, PROB_MAX);
3895       inc_sp(nargs);
3896       uncommon_trap(Deoptimization::Reason_class_check,
3897                     Deoptimization::Action_maybe_recompile);
3898     }
3899     layout_val = nullptr;
3900     layout_is_con = true;
3901   }
3902 
3903   // Generate the initial go-slow test.  Make sure we do not overflow
3904   // if length is huge (near 2Gig) or negative!  We do not need
3905   // exact double-words here, just a close approximation of needed
3906   // double-words.  We can't add any offset or rounding bits, lest we
3907   // take a size -1 of bytes and make it positive.  Use an unsigned
3908   // compare, so negative sizes look hugely positive.
3909   int fast_size_limit = FastAllocateSizeLimit;
3910   if (layout_is_con) {
3911     assert(!StressReflectiveCode, "stress mode does not use these paths");
3912     // Increase the size limit if we have exact knowledge of array type.
3913     int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3914     fast_size_limit <<= (LogBytesPerLong - log2_esize);
3915   }
3916 
3917   Node* initial_slow_cmp  = _gvn.transform( new CmpUNode( length, intcon( fast_size_limit ) ) );
3918   Node* initial_slow_test = _gvn.transform( new BoolNode( initial_slow_cmp, BoolTest::gt ) );
3919 
3920   // --- Size Computation ---
3921   // array_size = round_to_heap(array_header + (length << elem_shift));
3922   // where round_to_heap(x) == align_to(x, MinObjAlignmentInBytes)
3923   // and align_to(x, y) == ((x + y-1) & ~(y-1))
3924   // The rounding mask is strength-reduced, if possible.
3925   int round_mask = MinObjAlignmentInBytes - 1;
3926   Node* header_size = nullptr;
3927   // (T_BYTE has the weakest alignment and size restrictions...)
3928   if (layout_is_con) {
3929     int       hsize  = Klass::layout_helper_header_size(layout_con);
3930     int       eshift = Klass::layout_helper_log2_element_size(layout_con);
3931     if ((round_mask & ~right_n_bits(eshift)) == 0)
3932       round_mask = 0;  // strength-reduce it if it goes away completely
3933     assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3934     int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3935     assert(header_size_min <= hsize, "generic minimum is smallest");
3936     header_size = intcon(hsize);
3937   } else {
3938     Node* hss   = intcon(Klass::_lh_header_size_shift);
3939     Node* hsm   = intcon(Klass::_lh_header_size_mask);
3940     header_size = _gvn.transform(new URShiftINode(layout_val, hss));
3941     header_size = _gvn.transform(new AndINode(header_size, hsm));
3942   }
3943 
3944   Node* elem_shift = nullptr;
3945   if (layout_is_con) {
3946     int eshift = Klass::layout_helper_log2_element_size(layout_con);
3947     if (eshift != 0)
3948       elem_shift = intcon(eshift);
3949   } else {
3950     // There is no need to mask or shift this value.
3951     // The semantics of LShiftINode include an implicit mask to 0x1F.
3952     assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3953     elem_shift = layout_val;
3954   }
3955 
3956   // Transition to native address size for all offset calculations:
3957   Node* lengthx = ConvI2X(length);
3958   Node* headerx = ConvI2X(header_size);
3959 #ifdef _LP64
3960   { const TypeInt* tilen = _gvn.find_int_type(length);
3961     if (tilen != nullptr && tilen->_lo < 0) {
3962       // Add a manual constraint to a positive range.  Cf. array_element_address.
3963       jint size_max = fast_size_limit;
3964       if (size_max > tilen->_hi)  size_max = tilen->_hi;
3965       const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin);
3966 
3967       // Only do a narrow I2L conversion if the range check passed.
3968       IfNode* iff = new IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
3969       _gvn.transform(iff);
3970       RegionNode* region = new RegionNode(3);
3971       _gvn.set_type(region, Type::CONTROL);
3972       lengthx = new PhiNode(region, TypeLong::LONG);
3973       _gvn.set_type(lengthx, TypeLong::LONG);
3974 
3975       // Range check passed. Use ConvI2L node with narrow type.
3976       Node* passed = IfFalse(iff);
3977       region->init_req(1, passed);
3978       // Make I2L conversion control dependent to prevent it from
3979       // floating above the range check during loop optimizations.
3980       lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed));
3981 
3982       // Range check failed. Use ConvI2L with wide type because length may be invalid.
3983       region->init_req(2, IfTrue(iff));
3984       lengthx->init_req(2, ConvI2X(length));
3985 
3986       set_control(region);
3987       record_for_igvn(region);
3988       record_for_igvn(lengthx);
3989     }
3990   }
3991 #endif
3992 
3993   // Combine header size and body size for the array copy part, then align (if
3994   // necessary) for the allocation part. This computation cannot overflow,
3995   // because it is used only in two places, one where the length is sharply
3996   // limited, and the other after a successful allocation.
3997   Node* abody = lengthx;
3998   if (elem_shift != nullptr) {
3999     abody = _gvn.transform(new LShiftXNode(lengthx, elem_shift));
4000   }
4001   Node* non_rounded_size = _gvn.transform(new AddXNode(headerx, abody));
4002 
4003   if (return_size_val != nullptr) {
4004     // This is the size
4005     (*return_size_val) = non_rounded_size;
4006   }
4007 
4008   Node* size = non_rounded_size;
4009   if (round_mask != 0) {
4010     Node* mask1 = MakeConX(round_mask);
4011     size = _gvn.transform(new AddXNode(size, mask1));
4012     Node* mask2 = MakeConX(~round_mask);
4013     size = _gvn.transform(new AndXNode(size, mask2));
4014   }
4015   // else if round_mask == 0, the size computation is self-rounding
4016 
4017   // Now generate allocation code
4018 
4019   // The entire memory state is needed for slow path of the allocation
4020   // since GC and deoptimization can happened.
4021   Node *mem = reset_memory();
4022   set_all_memory(mem); // Create new memory state
4023 
4024   if (initial_slow_test->is_Bool()) {
4025     // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
4026     initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
4027   }
4028 
4029   const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
4030   Node* valid_length_test = _gvn.intcon(1);
4031   if (ary_type->isa_aryptr()) {
4032     BasicType bt = ary_type->isa_aryptr()->elem()->array_element_basic_type();
4033     jint max = TypeAryPtr::max_array_length(bt);
4034     Node* valid_length_cmp  = _gvn.transform(new CmpUNode(length, intcon(max)));
4035     valid_length_test = _gvn.transform(new BoolNode(valid_length_cmp, BoolTest::le));
4036   }
4037 
4038   // Create the AllocateArrayNode and its result projections
4039   AllocateArrayNode* alloc
4040     = new AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
4041                             control(), mem, i_o(),
4042                             size, klass_node,
4043                             initial_slow_test,
4044                             length, valid_length_test);
4045 
4046   // Cast to correct type.  Note that the klass_node may be constant or not,
4047   // and in the latter case the actual array type will be inexact also.
4048   // (This happens via a non-constant argument to inline_native_newArray.)
4049   // In any case, the value of klass_node provides the desired array type.
4050   const TypeInt* length_type = _gvn.find_int_type(length);
4051   if (ary_type->isa_aryptr() && length_type != nullptr) {
4052     // Try to get a better type than POS for the size
4053     ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
4054   }
4055 
4056   Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception);
4057 
4058   array_ideal_length(alloc, ary_type, true);
4059   return javaoop;
4060 }
4061 
4062 // The following "Ideal_foo" functions are placed here because they recognize
4063 // the graph shapes created by the functions immediately above.
4064 
4065 //---------------------------Ideal_allocation----------------------------------
4066 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
4067 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr) {
4068   if (ptr == nullptr) {     // reduce dumb test in callers
4069     return nullptr;
4070   }
4071 
4072   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
4073   ptr = bs->step_over_gc_barrier(ptr);
4074 
4075   if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
4076     ptr = ptr->in(1);
4077     if (ptr == nullptr) return nullptr;
4078   }
4079   // Return null for allocations with several casts:
4080   //   j.l.reflect.Array.newInstance(jobject, jint)
4081   //   Object.clone()
4082   // to keep more precise type from last cast.
4083   if (ptr->is_Proj()) {
4084     Node* allo = ptr->in(0);
4085     if (allo != nullptr && allo->is_Allocate()) {
4086       return allo->as_Allocate();
4087     }
4088   }
4089   // Report failure to match.
4090   return nullptr;
4091 }
4092 
4093 // Fancy version which also strips off an offset (and reports it to caller).
4094 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseValues* phase,
4095                                              intptr_t& offset) {
4096   Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
4097   if (base == nullptr)  return nullptr;
4098   return Ideal_allocation(base);
4099 }
4100 
4101 // Trace Initialize <- Proj[Parm] <- Allocate
4102 AllocateNode* InitializeNode::allocation() {
4103   Node* rawoop = in(InitializeNode::RawAddress);
4104   if (rawoop->is_Proj()) {
4105     Node* alloc = rawoop->in(0);
4106     if (alloc->is_Allocate()) {
4107       return alloc->as_Allocate();
4108     }
4109   }
4110   return nullptr;
4111 }
4112 
4113 // Trace Allocate -> Proj[Parm] -> Initialize
4114 InitializeNode* AllocateNode::initialization() {
4115   ProjNode* rawoop = proj_out_or_null(AllocateNode::RawAddress);
4116   if (rawoop == nullptr)  return nullptr;
4117   for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
4118     Node* init = rawoop->fast_out(i);
4119     if (init->is_Initialize()) {
4120       assert(init->as_Initialize()->allocation() == this, "2-way link");
4121       return init->as_Initialize();
4122     }
4123   }
4124   return nullptr;
4125 }
4126 
4127 // Add a Parse Predicate with an uncommon trap on the failing/false path. Normal control will continue on the true path.
4128 void GraphKit::add_parse_predicate(Deoptimization::DeoptReason reason, const int nargs) {
4129   // Too many traps seen?
4130   if (too_many_traps(reason)) {
4131 #ifdef ASSERT
4132     if (TraceLoopPredicate) {
4133       int tc = C->trap_count(reason);
4134       tty->print("too many traps=%s tcount=%d in ",
4135                     Deoptimization::trap_reason_name(reason), tc);
4136       method()->print(); // which method has too many predicate traps
4137       tty->cr();
4138     }
4139 #endif
4140     // We cannot afford to take more traps here,
4141     // do not generate Parse Predicate.
4142     return;
4143   }
4144 
4145   ParsePredicateNode* parse_predicate = new ParsePredicateNode(control(), reason, &_gvn);
4146   _gvn.set_type(parse_predicate, parse_predicate->Value(&_gvn));
4147   Node* if_false = _gvn.transform(new IfFalseNode(parse_predicate));
4148   {
4149     PreserveJVMState pjvms(this);
4150     set_control(if_false);
4151     inc_sp(nargs);
4152     uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
4153   }
4154   Node* if_true = _gvn.transform(new IfTrueNode(parse_predicate));
4155   set_control(if_true);
4156 }
4157 
4158 // Add Parse Predicates which serve as placeholders to create new Runtime Predicates above them. All
4159 // Runtime Predicates inside a Runtime Predicate block share the same uncommon trap as the Parse Predicate.
4160 void GraphKit::add_parse_predicates(int nargs) {
4161   if (UseLoopPredicate) {
4162     add_parse_predicate(Deoptimization::Reason_predicate, nargs);
4163   }
4164   if (UseProfiledLoopPredicate) {
4165     add_parse_predicate(Deoptimization::Reason_profile_predicate, nargs);
4166   }
4167   // Loop Limit Check Predicate should be near the loop.
4168   add_parse_predicate(Deoptimization::Reason_loop_limit_check, nargs);
4169 }
4170 
4171 void GraphKit::sync_kit(IdealKit& ideal) {
4172   set_all_memory(ideal.merged_memory());
4173   set_i_o(ideal.i_o());
4174   set_control(ideal.ctrl());
4175 }
4176 
4177 void GraphKit::final_sync(IdealKit& ideal) {
4178   // Final sync IdealKit and graphKit.
4179   sync_kit(ideal);
4180 }
4181 
4182 Node* GraphKit::load_String_length(Node* str, bool set_ctrl) {
4183   Node* len = load_array_length(load_String_value(str, set_ctrl));
4184   Node* coder = load_String_coder(str, set_ctrl);
4185   // Divide length by 2 if coder is UTF16
4186   return _gvn.transform(new RShiftINode(len, coder));
4187 }
4188 
4189 Node* GraphKit::load_String_value(Node* str, bool set_ctrl) {
4190   int value_offset = java_lang_String::value_offset();
4191   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4192                                                      false, nullptr, 0);
4193   const TypePtr* value_field_type = string_type->add_offset(value_offset);
4194   const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
4195                                                   TypeAry::make(TypeInt::BYTE, TypeInt::POS),
4196                                                   ciTypeArrayKlass::make(T_BYTE), true, 0);
4197   Node* p = basic_plus_adr(str, str, value_offset);
4198   Node* load = access_load_at(str, p, value_field_type, value_type, T_OBJECT,
4199                               IN_HEAP | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0) | MO_UNORDERED);
4200   return load;
4201 }
4202 
4203 Node* GraphKit::load_String_coder(Node* str, bool set_ctrl) {
4204   if (!CompactStrings) {
4205     return intcon(java_lang_String::CODER_UTF16);
4206   }
4207   int coder_offset = java_lang_String::coder_offset();
4208   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4209                                                      false, nullptr, 0);
4210   const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4211 
4212   Node* p = basic_plus_adr(str, str, coder_offset);
4213   Node* load = access_load_at(str, p, coder_field_type, TypeInt::BYTE, T_BYTE,
4214                               IN_HEAP | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0) | MO_UNORDERED);
4215   return load;
4216 }
4217 
4218 void GraphKit::store_String_value(Node* str, Node* value) {
4219   int value_offset = java_lang_String::value_offset();
4220   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4221                                                      false, nullptr, 0);
4222   const TypePtr* value_field_type = string_type->add_offset(value_offset);
4223 
4224   access_store_at(str,  basic_plus_adr(str, value_offset), value_field_type,
4225                   value, TypeAryPtr::BYTES, T_OBJECT, IN_HEAP | MO_UNORDERED);
4226 }
4227 
4228 void GraphKit::store_String_coder(Node* str, Node* value) {
4229   int coder_offset = java_lang_String::coder_offset();
4230   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4231                                                      false, nullptr, 0);
4232   const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4233 
4234   access_store_at(str, basic_plus_adr(str, coder_offset), coder_field_type,
4235                   value, TypeInt::BYTE, T_BYTE, IN_HEAP | MO_UNORDERED);
4236 }
4237 
4238 // Capture src and dst memory state with a MergeMemNode
4239 Node* GraphKit::capture_memory(const TypePtr* src_type, const TypePtr* dst_type) {
4240   if (src_type == dst_type) {
4241     // Types are equal, we don't need a MergeMemNode
4242     return memory(src_type);
4243   }
4244   MergeMemNode* merge = MergeMemNode::make(map()->memory());
4245   record_for_igvn(merge); // fold it up later, if possible
4246   int src_idx = C->get_alias_index(src_type);
4247   int dst_idx = C->get_alias_index(dst_type);
4248   merge->set_memory_at(src_idx, memory(src_idx));
4249   merge->set_memory_at(dst_idx, memory(dst_idx));
4250   return merge;
4251 }
4252 
4253 Node* GraphKit::compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count) {
4254   assert(Matcher::match_rule_supported(Op_StrCompressedCopy), "Intrinsic not supported");
4255   assert(src_type == TypeAryPtr::BYTES || src_type == TypeAryPtr::CHARS, "invalid source type");
4256   // If input and output memory types differ, capture both states to preserve
4257   // the dependency between preceding and subsequent loads/stores.
4258   // For example, the following program:
4259   //  StoreB
4260   //  compress_string
4261   //  LoadB
4262   // has this memory graph (use->def):
4263   //  LoadB -> compress_string -> CharMem
4264   //             ... -> StoreB -> ByteMem
4265   // The intrinsic hides the dependency between LoadB and StoreB, causing
4266   // the load to read from memory not containing the result of the StoreB.
4267   // The correct memory graph should look like this:
4268   //  LoadB -> compress_string -> MergeMem(CharMem, StoreB(ByteMem))
4269   Node* mem = capture_memory(src_type, TypeAryPtr::BYTES);
4270   StrCompressedCopyNode* str = new StrCompressedCopyNode(control(), mem, src, dst, count);
4271   Node* res_mem = _gvn.transform(new SCMemProjNode(_gvn.transform(str)));
4272   set_memory(res_mem, TypeAryPtr::BYTES);
4273   return str;
4274 }
4275 
4276 void GraphKit::inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count) {
4277   assert(Matcher::match_rule_supported(Op_StrInflatedCopy), "Intrinsic not supported");
4278   assert(dst_type == TypeAryPtr::BYTES || dst_type == TypeAryPtr::CHARS, "invalid dest type");
4279   // Capture src and dst memory (see comment in 'compress_string').
4280   Node* mem = capture_memory(TypeAryPtr::BYTES, dst_type);
4281   StrInflatedCopyNode* str = new StrInflatedCopyNode(control(), mem, src, dst, count);
4282   set_memory(_gvn.transform(str), dst_type);
4283 }
4284 
4285 void GraphKit::inflate_string_slow(Node* src, Node* dst, Node* start, Node* count) {
4286   /**
4287    * int i_char = start;
4288    * for (int i_byte = 0; i_byte < count; i_byte++) {
4289    *   dst[i_char++] = (char)(src[i_byte] & 0xff);
4290    * }
4291    */
4292   add_parse_predicates();
4293   C->set_has_loops(true);
4294 
4295   RegionNode* head = new RegionNode(3);
4296   head->init_req(1, control());
4297   gvn().set_type(head, Type::CONTROL);
4298   record_for_igvn(head);
4299 
4300   Node* i_byte = new PhiNode(head, TypeInt::INT);
4301   i_byte->init_req(1, intcon(0));
4302   gvn().set_type(i_byte, TypeInt::INT);
4303   record_for_igvn(i_byte);
4304 
4305   Node* i_char = new PhiNode(head, TypeInt::INT);
4306   i_char->init_req(1, start);
4307   gvn().set_type(i_char, TypeInt::INT);
4308   record_for_igvn(i_char);
4309 
4310   Node* mem = PhiNode::make(head, memory(TypeAryPtr::BYTES), Type::MEMORY, TypeAryPtr::BYTES);
4311   gvn().set_type(mem, Type::MEMORY);
4312   record_for_igvn(mem);
4313   set_control(head);
4314   set_memory(mem, TypeAryPtr::BYTES);
4315   Node* ch = load_array_element(src, i_byte, TypeAryPtr::BYTES, /* set_ctrl */ true);
4316   Node* st = store_to_memory(control(), array_element_address(dst, i_char, T_BYTE),
4317                              AndI(ch, intcon(0xff)), T_CHAR, MemNode::unordered, false,
4318                              false, true /* mismatched */);
4319 
4320   IfNode* iff = create_and_map_if(head, Bool(CmpI(i_byte, count), BoolTest::lt), PROB_FAIR, COUNT_UNKNOWN);
4321   head->init_req(2, IfTrue(iff));
4322   mem->init_req(2, st);
4323   i_byte->init_req(2, AddI(i_byte, intcon(1)));
4324   i_char->init_req(2, AddI(i_char, intcon(2)));
4325 
4326   set_control(IfFalse(iff));
4327   set_memory(st, TypeAryPtr::BYTES);
4328 }
4329 
4330 Node* GraphKit::make_constant_from_field(ciField* field, Node* obj) {
4331   if (!field->is_constant()) {
4332     return nullptr; // Field not marked as constant.
4333   }
4334   ciInstance* holder = nullptr;
4335   if (!field->is_static()) {
4336     ciObject* const_oop = obj->bottom_type()->is_oopptr()->const_oop();
4337     if (const_oop != nullptr && const_oop->is_instance()) {
4338       holder = const_oop->as_instance();
4339     }
4340   }
4341   const Type* con_type = Type::make_constant_from_field(field, holder, field->layout_type(),
4342                                                         /*is_unsigned_load=*/false);
4343   if (con_type != nullptr) {
4344     return makecon(con_type);
4345   }
4346   return nullptr;
4347 }
4348 
4349 Node* GraphKit::maybe_narrow_object_type(Node* obj, ciKlass* type) {
4350   const TypeOopPtr* obj_type = obj->bottom_type()->isa_oopptr();
4351   const TypeOopPtr* sig_type = TypeOopPtr::make_from_klass(type);
4352   if (obj_type != nullptr && sig_type->is_loaded() && !obj_type->higher_equal(sig_type)) {
4353     const Type* narrow_obj_type = obj_type->filter_speculative(sig_type); // keep speculative part
4354     Node* casted_obj = gvn().transform(new CheckCastPPNode(control(), obj, narrow_obj_type));
4355     return casted_obj;
4356   }
4357   return obj;
4358 }