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