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src/hotspot/share/opto/parse1.cpp

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  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 "compiler/compileLog.hpp"
  26 #include "interpreter/linkResolver.hpp"
  27 #include "memory/resourceArea.hpp"
  28 #include "oops/method.hpp"
  29 #include "opto/addnode.hpp"
  30 #include "opto/c2compiler.hpp"
  31 #include "opto/castnode.hpp"

  32 #include "opto/idealGraphPrinter.hpp"

  33 #include "opto/locknode.hpp"
  34 #include "opto/memnode.hpp"
  35 #include "opto/opaquenode.hpp"
  36 #include "opto/parse.hpp"
  37 #include "opto/rootnode.hpp"
  38 #include "opto/runtime.hpp"
  39 #include "opto/type.hpp"
  40 #include "runtime/handles.inline.hpp"
  41 #include "runtime/safepointMechanism.hpp"
  42 #include "runtime/sharedRuntime.hpp"
  43 #include "utilities/bitMap.inline.hpp"
  44 #include "utilities/copy.hpp"
  45 
  46 // Static array so we can figure out which bytecodes stop us from compiling
  47 // the most. Some of the non-static variables are needed in bytecodeInfo.cpp
  48 // and eventually should be encapsulated in a proper class (gri 8/18/98).
  49 
  50 #ifndef PRODUCT
  51 uint nodes_created             = 0;
  52 uint methods_parsed            = 0;

  84   }
  85   if (all_null_checks_found) {
  86     tty->print_cr("%u made implicit (%2u%%)", implicit_null_checks,
  87                   (100*implicit_null_checks)/all_null_checks_found);
  88   }
  89   if (SharedRuntime::_implicit_null_throws) {
  90     tty->print_cr("%u implicit null exceptions at runtime",
  91                   SharedRuntime::_implicit_null_throws);
  92   }
  93 
  94   if (PrintParseStatistics && BytecodeParseHistogram::initialized()) {
  95     BytecodeParseHistogram::print();
  96   }
  97 }
  98 #endif
  99 
 100 //------------------------------ON STACK REPLACEMENT---------------------------
 101 
 102 // Construct a node which can be used to get incoming state for
 103 // on stack replacement.
 104 Node *Parse::fetch_interpreter_state(int index,
 105                                      BasicType bt,
 106                                      Node *local_addrs,
 107                                      Node *local_addrs_base) {






 108   Node *mem = memory(Compile::AliasIdxRaw);
 109   Node *adr = basic_plus_adr( local_addrs_base, local_addrs, -index*wordSize );
 110   Node *ctl = control();
 111 
 112   // Very similar to LoadNode::make, except we handle un-aligned longs and
 113   // doubles on Sparc.  Intel can handle them just fine directly.
 114   Node *l = nullptr;
 115   switch (bt) {                // Signature is flattened
 116   case T_INT:     l = new LoadINode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInt::INT,        MemNode::unordered); break;
 117   case T_FLOAT:   l = new LoadFNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::FLOAT,         MemNode::unordered); break;
 118   case T_ADDRESS: l = new LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM,  MemNode::unordered); break;
 119   case T_OBJECT:  l = new LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInstPtr::BOTTOM, MemNode::unordered); break;
 120   case T_LONG:
 121   case T_DOUBLE: {
 122     // Since arguments are in reverse order, the argument address 'adr'
 123     // refers to the back half of the long/double.  Recompute adr.
 124     adr = basic_plus_adr(local_addrs_base, local_addrs, -(index+1)*wordSize);
 125     if (Matcher::misaligned_doubles_ok) {
 126       l = (bt == T_DOUBLE)
 127         ? (Node*)new LoadDNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::DOUBLE, MemNode::unordered)
 128         : (Node*)new LoadLNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeLong::LONG, MemNode::unordered);
 129     } else {
 130       l = (bt == T_DOUBLE)
 131         ? (Node*)new LoadD_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered)
 132         : (Node*)new LoadL_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered);
 133     }
 134     break;
 135   }
 136   default: ShouldNotReachHere();
 137   }
 138   return _gvn.transform(l);
 139 }
 140 
 141 // Helper routine to prevent the interpreter from handing
 142 // unexpected typestate to an OSR method.
 143 // The Node l is a value newly dug out of the interpreter frame.
 144 // The type is the type predicted by ciTypeFlow.  Note that it is
 145 // not a general type, but can only come from Type::get_typeflow_type.
 146 // The safepoint is a map which will feed an uncommon trap.
 147 Node* Parse::check_interpreter_type(Node* l, const Type* type,
 148                                     SafePointNode* &bad_type_exit) {
 149 
 150   const TypeOopPtr* tp = type->isa_oopptr();
 151 
 152   // TypeFlow may assert null-ness if a type appears unloaded.
 153   if (type == TypePtr::NULL_PTR ||
 154       (tp != nullptr && !tp->is_loaded())) {
 155     // Value must be null, not a real oop.
 156     Node* chk = _gvn.transform( new CmpPNode(l, null()) );
 157     Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
 158     IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
 159     set_control(_gvn.transform( new IfTrueNode(iff) ));
 160     Node* bad_type = _gvn.transform( new IfFalseNode(iff) );
 161     bad_type_exit->control()->add_req(bad_type);
 162     l = null();
 163   }
 164 
 165   // Typeflow can also cut off paths from the CFG, based on
 166   // types which appear unloaded, or call sites which appear unlinked.
 167   // When paths are cut off, values at later merge points can rise
 168   // toward more specific classes.  Make sure these specific classes
 169   // are still in effect.
 170   if (tp != nullptr && !tp->is_same_java_type_as(TypeInstPtr::BOTTOM)) {
 171     // TypeFlow asserted a specific object type.  Value must have that type.
 172     Node* bad_type_ctrl = nullptr;
 173     l = gen_checkcast(l, makecon(tp->as_klass_type()->cast_to_exactness(true)), &bad_type_ctrl);







 174     bad_type_exit->control()->add_req(bad_type_ctrl);
 175   }
 176 
 177   assert(_gvn.type(l)->higher_equal(type), "must constrain OSR typestate");
 178   return l;
 179 }
 180 
 181 // Helper routine which sets up elements of the initial parser map when
 182 // performing a parse for on stack replacement.  Add values into map.
 183 // The only parameter contains the address of a interpreter arguments.
 184 void Parse::load_interpreter_state(Node* osr_buf) {
 185   int index;
 186   int max_locals = jvms()->loc_size();
 187   int max_stack  = jvms()->stk_size();
 188 
 189 
 190   // Mismatch between method and jvms can occur since map briefly held
 191   // an OSR entry state (which takes up one RawPtr word).
 192   assert(max_locals == method()->max_locals(), "sanity");
 193   assert(max_stack  >= method()->max_stack(),  "sanity");
 194   assert((int)jvms()->endoff() == TypeFunc::Parms + max_locals + max_stack, "sanity");
 195   assert((int)jvms()->endoff() == (int)map()->req(), "sanity");
 196 
 197   // Find the start block.
 198   Block* osr_block = start_block();
 199   assert(osr_block->start() == osr_bci(), "sanity");
 200 
 201   // Set initial BCI.
 202   set_parse_bci(osr_block->start());
 203 
 204   // Set initial stack depth.
 205   set_sp(osr_block->start_sp());
 206 
 207   // Check bailouts.  We currently do not perform on stack replacement
 208   // of loops in catch blocks or loops which branch with a non-empty stack.
 209   if (sp() != 0) {

 224   for (index = 0; index < mcnt; index++) {
 225     // Make a BoxLockNode for the monitor.
 226     BoxLockNode* osr_box = new BoxLockNode(next_monitor());
 227     // Check for bailout after new BoxLockNode
 228     if (failing()) { return; }
 229 
 230     // This OSR locking region is unbalanced because it does not have Lock node:
 231     // locking was done in Interpreter.
 232     // This is similar to Coarsened case when Lock node is eliminated
 233     // and as result the region is marked as Unbalanced.
 234 
 235     // Emulate Coarsened state transition from Regular to Unbalanced.
 236     osr_box->set_coarsened();
 237     osr_box->set_unbalanced();
 238 
 239     Node* box = _gvn.transform(osr_box);
 240 
 241     // Displaced headers and locked objects are interleaved in the
 242     // temp OSR buffer.  We only copy the locked objects out here.
 243     // Fetch the locked object from the OSR temp buffer and copy to our fastlock node.
 244     Node *lock_object = fetch_interpreter_state(index*2, T_OBJECT, monitors_addr, osr_buf);
 245     // Try and copy the displaced header to the BoxNode
 246     Node *displaced_hdr = fetch_interpreter_state((index*2) + 1, T_ADDRESS, monitors_addr, osr_buf);
 247 
 248 
 249     store_to_memory(control(), box, displaced_hdr, T_ADDRESS, MemNode::unordered);
 250 
 251     // Build a bogus FastLockNode (no code will be generated) and push the
 252     // monitor into our debug info.
 253     const FastLockNode *flock = _gvn.transform(new FastLockNode( nullptr, lock_object, box ))->as_FastLock();
 254     map()->push_monitor(flock);
 255 
 256     // If the lock is our method synchronization lock, tuck it away in
 257     // _sync_lock for return and rethrow exit paths.
 258     if (index == 0 && method()->is_synchronized()) {
 259       _synch_lock = flock;
 260     }
 261   }
 262 
 263   // Use the raw liveness computation to make sure that unexpected
 264   // values don't propagate into the OSR frame.
 265   MethodLivenessResult live_locals = method()->liveness_at_bci(osr_bci());
 266   if (!live_locals.is_valid()) {
 267     // Degenerate or breakpointed method.

 295         if (C->log() != nullptr) {
 296           C->log()->elem("OSR_mismatch local_index='%d'",index);
 297         }
 298         set_local(index, null());
 299         // and ignore it for the loads
 300         continue;
 301       }
 302     }
 303 
 304     // Filter out TOP, HALF, and BOTTOM.  (Cf. ensure_phi.)
 305     if (type == Type::TOP || type == Type::HALF) {
 306       continue;
 307     }
 308     // If the type falls to bottom, then this must be a local that
 309     // is mixing ints and oops or some such.  Forcing it to top
 310     // makes it go dead.
 311     if (type == Type::BOTTOM) {
 312       continue;
 313     }
 314     // Construct code to access the appropriate local.
 315     BasicType bt = type->basic_type();
 316     if (type == TypePtr::NULL_PTR) {
 317       // Ptr types are mixed together with T_ADDRESS but null is
 318       // really for T_OBJECT types so correct it.
 319       bt = T_OBJECT;
 320     }
 321     Node *value = fetch_interpreter_state(index, bt, locals_addr, osr_buf);
 322     set_local(index, value);
 323   }
 324 
 325   // Extract the needed stack entries from the interpreter frame.
 326   for (index = 0; index < sp(); index++) {
 327     const Type *type = osr_block->stack_type_at(index);
 328     if (type != Type::TOP) {
 329       // Currently the compiler bails out when attempting to on stack replace
 330       // at a bci with a non-empty stack.  We should not reach here.
 331       ShouldNotReachHere();
 332     }
 333   }
 334 
 335   // End the OSR migration
 336   make_runtime_call(RC_LEAF, OptoRuntime::osr_end_Type(),
 337                     CAST_FROM_FN_PTR(address, SharedRuntime::OSR_migration_end),
 338                     "OSR_migration_end", TypeRawPtr::BOTTOM,
 339                     osr_buf);
 340 
 341   // Now that the interpreter state is loaded, make sure it will match

 352     if (type->isa_oopptr() != nullptr) {
 353       if (!live_oops.at(index)) {
 354         // skip type check for dead oops
 355         continue;
 356       }
 357     }
 358     if (osr_block->flow()->local_type_at(index)->is_return_address()) {
 359       // In our current system it's illegal for jsr addresses to be
 360       // live into an OSR entry point because the compiler performs
 361       // inlining of jsrs.  ciTypeFlow has a bailout that detect this
 362       // case and aborts the compile if addresses are live into an OSR
 363       // entry point.  Because of that we can assume that any address
 364       // locals at the OSR entry point are dead.  Method liveness
 365       // isn't precise enough to figure out that they are dead in all
 366       // cases so simply skip checking address locals all
 367       // together. Any type check is guaranteed to fail since the
 368       // interpreter type is the result of a load which might have any
 369       // value and the expected type is a constant.
 370       continue;
 371     }
 372     set_local(index, check_interpreter_type(l, type, bad_type_exit));

 373   }
 374 
 375   for (index = 0; index < sp(); index++) {
 376     if (stopped())  break;
 377     Node* l = stack(index);
 378     if (l->is_top())  continue;  // nothing here
 379     const Type *type = osr_block->stack_type_at(index);
 380     set_stack(index, check_interpreter_type(l, type, bad_type_exit));

 381   }
 382 
 383   if (bad_type_exit->control()->req() > 1) {
 384     // Build an uncommon trap here, if any inputs can be unexpected.
 385     bad_type_exit->set_control(_gvn.transform( bad_type_exit->control() ));
 386     record_for_igvn(bad_type_exit->control());
 387     SafePointNode* types_are_good = map();
 388     set_map(bad_type_exit);
 389     // The unexpected type happens because a new edge is active
 390     // in the CFG, which typeflow had previously ignored.
 391     // E.g., Object x = coldAtFirst() && notReached()? "str": new Integer(123).
 392     // This x will be typed as Integer if notReached is not yet linked.
 393     // It could also happen due to a problem in ciTypeFlow analysis.
 394     uncommon_trap(Deoptimization::Reason_constraint,
 395                   Deoptimization::Action_reinterpret);
 396     set_map(types_are_good);
 397   }
 398 }
 399 
 400 //------------------------------Parse------------------------------------------

 501   // either breakpoint setting or hotswapping of methods may
 502   // cause deoptimization.
 503   if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
 504     C->dependencies()->assert_evol_method(method());
 505   }
 506 
 507   NOT_PRODUCT(methods_seen++);
 508 
 509   // Do some special top-level things.
 510   if (depth() == 1 && C->is_osr_compilation()) {
 511     _tf = C->tf();     // the OSR entry type is different
 512     _entry_bci = C->entry_bci();
 513     _flow = method()->get_osr_flow_analysis(osr_bci());
 514   } else {
 515     _tf = TypeFunc::make(method());
 516     _entry_bci = InvocationEntryBci;
 517     _flow = method()->get_flow_analysis();
 518   }
 519 
 520   if (_flow->failing()) {
 521     assert(false, "type flow analysis failed during parsing");


 522     C->record_method_not_compilable(_flow->failure_reason());
 523 #ifndef PRODUCT
 524       if (PrintOpto && (Verbose || WizardMode)) {
 525         if (is_osr_parse()) {
 526           tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
 527         } else {
 528           tty->print_cr("type flow bailout: %s", _flow->failure_reason());
 529         }
 530         if (Verbose) {
 531           method()->print();
 532           method()->print_codes();
 533           _flow->print();
 534         }
 535       }
 536 #endif
 537   }
 538 
 539 #ifdef ASSERT
 540   if (depth() == 1) {
 541     assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");

 592     load_interpreter_state(osr_buf);
 593   } else {
 594     set_map(entry_map);
 595     do_method_entry();
 596   }
 597 
 598   if (depth() == 1 && !failing()) {
 599     if (C->clinit_barrier_on_entry()) {
 600       // Add check to deoptimize the nmethod once the holder class is fully initialized
 601       clinit_deopt();
 602     }
 603   }
 604 
 605   // Check for bailouts during method entry.
 606   if (failing()) {
 607     if (log)  log->done("parse");
 608     C->set_default_node_notes(caller_nn);
 609     return;
 610   }
 611 


























 612   entry_map = map();  // capture any changes performed by method setup code
 613   assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");
 614 
 615   // We begin parsing as if we have just encountered a jump to the
 616   // method entry.
 617   Block* entry_block = start_block();
 618   assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
 619   set_map_clone(entry_map);
 620   merge_common(entry_block, entry_block->next_path_num());
 621 
 622 #ifndef PRODUCT
 623   BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
 624   set_parse_histogram( parse_histogram_obj );
 625 #endif
 626 
 627   // Parse all the basic blocks.
 628   do_all_blocks();
 629 
 630   // Check for bailouts during conversion to graph
 631   if (failing()) {

 777 void Parse::build_exits() {
 778   // make a clone of caller to prevent sharing of side-effects
 779   _exits.set_map(_exits.clone_map());
 780   _exits.clean_stack(_exits.sp());
 781   _exits.sync_jvms();
 782 
 783   RegionNode* region = new RegionNode(1);
 784   record_for_igvn(region);
 785   gvn().set_type_bottom(region);
 786   _exits.set_control(region);
 787 
 788   // Note:  iophi and memphi are not transformed until do_exits.
 789   Node* iophi  = new PhiNode(region, Type::ABIO);
 790   Node* memphi = new PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
 791   gvn().set_type_bottom(iophi);
 792   gvn().set_type_bottom(memphi);
 793   _exits.set_i_o(iophi);
 794   _exits.set_all_memory(memphi);
 795 
 796   // Add a return value to the exit state.  (Do not push it yet.)
 797   if (tf()->range()->cnt() > TypeFunc::Parms) {
 798     const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
 799     if (ret_type->isa_int()) {
 800       BasicType ret_bt = method()->return_type()->basic_type();
 801       if (ret_bt == T_BOOLEAN ||
 802           ret_bt == T_CHAR ||
 803           ret_bt == T_BYTE ||
 804           ret_bt == T_SHORT) {
 805         ret_type = TypeInt::INT;
 806       }
 807     }
 808 
 809     // Don't "bind" an unloaded return klass to the ret_phi. If the klass
 810     // becomes loaded during the subsequent parsing, the loaded and unloaded
 811     // types will not join when we transform and push in do_exits().
 812     const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
 813     if (ret_oop_type && !ret_oop_type->is_loaded()) {
 814       ret_type = TypeOopPtr::BOTTOM;
 815     }
 816     int         ret_size = type2size[ret_type->basic_type()];
 817     Node*       ret_phi  = new PhiNode(region, ret_type);
 818     gvn().set_type_bottom(ret_phi);
 819     _exits.ensure_stack(ret_size);
 820     assert((int)(tf()->range()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
 821     assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
 822     _exits.set_argument(0, ret_phi);  // here is where the parser finds it
 823     // Note:  ret_phi is not yet pushed, until do_exits.
 824   }
 825 }
 826 
 827 
 828 //----------------------------build_start_state-------------------------------
 829 // Construct a state which contains only the incoming arguments from an
 830 // unknown caller.  The method & bci will be null & InvocationEntryBci.
 831 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
 832   int        arg_size = tf->domain()->cnt();
 833   int        max_size = MAX2(arg_size, (int)tf->range()->cnt());
 834   JVMState*  jvms     = new (this) JVMState(max_size - TypeFunc::Parms);
 835   SafePointNode* map  = new SafePointNode(max_size, jvms);

 836   record_for_igvn(map);
 837   assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
 838   Node_Notes* old_nn = default_node_notes();
 839   if (old_nn != nullptr && has_method()) {
 840     Node_Notes* entry_nn = old_nn->clone(this);
 841     JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
 842     entry_jvms->set_offsets(0);
 843     entry_jvms->set_bci(entry_bci());
 844     entry_nn->set_jvms(entry_jvms);
 845     set_default_node_notes(entry_nn);
 846   }
 847   uint i;
 848   for (i = 0; i < (uint)arg_size; i++) {
 849     Node* parm = initial_gvn()->transform(new ParmNode(start, i));

















 850     map->init_req(i, parm);
 851     // Record all these guys for later GVN.
 852     record_for_igvn(parm);



 853   }
 854   for (; i < map->req(); i++) {
 855     map->init_req(i, top());
 856   }
 857   assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
 858   set_default_node_notes(old_nn);
 859   jvms->set_map(map);
 860   return jvms;
 861 }
 862 
 863 //-----------------------------make_node_notes---------------------------------
 864 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
 865   if (caller_nn == nullptr)  return nullptr;
 866   Node_Notes* nn = caller_nn->clone(C);
 867   JVMState* caller_jvms = nn->jvms();
 868   JVMState* jvms = new (C) JVMState(method(), caller_jvms);
 869   jvms->set_offsets(0);
 870   jvms->set_bci(_entry_bci);
 871   nn->set_jvms(jvms);
 872   return nn;
 873 }
 874 
 875 
 876 //--------------------------return_values--------------------------------------
 877 void Compile::return_values(JVMState* jvms) {
 878   GraphKit kit(jvms);
 879   Node* ret = new ReturnNode(TypeFunc::Parms,
 880                              kit.control(),
 881                              kit.i_o(),
 882                              kit.reset_memory(),
 883                              kit.frameptr(),
 884                              kit.returnadr());
 885   // Add zero or 1 return values
 886   int ret_size = tf()->range()->cnt() - TypeFunc::Parms;
 887   if (ret_size > 0) {
 888     kit.inc_sp(-ret_size);  // pop the return value(s)
 889     kit.sync_jvms();
 890     ret->add_req(kit.argument(0));
 891     // Note:  The second dummy edge is not needed by a ReturnNode.






















 892   }
 893   // bind it to root
 894   root()->add_req(ret);
 895   record_for_igvn(ret);
 896   initial_gvn()->transform(ret);
 897 }
 898 
 899 //------------------------rethrow_exceptions-----------------------------------
 900 // Bind all exception states in the list into a single RethrowNode.
 901 void Compile::rethrow_exceptions(JVMState* jvms) {
 902   GraphKit kit(jvms);
 903   if (!kit.has_exceptions())  return;  // nothing to generate
 904   // Load my combined exception state into the kit, with all phis transformed:
 905   SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
 906   Node* ex_oop = kit.use_exception_state(ex_map);
 907   RethrowNode* exit = new RethrowNode(kit.control(),
 908                                       kit.i_o(), kit.reset_memory(),
 909                                       kit.frameptr(), kit.returnadr(),
 910                                       // like a return but with exception input
 911                                       ex_oop);

 995   //    to complete, we force all writes to complete.
 996   //
 997   // 2. Experimental VM option is used to force the barrier if any field
 998   //    was written out in the constructor.
 999   //
1000   // 3. On processors which are not CPU_MULTI_COPY_ATOMIC (e.g. PPC64),
1001   //    support_IRIW_for_not_multiple_copy_atomic_cpu selects that
1002   //    MemBarVolatile is used before volatile load instead of after volatile
1003   //    store, so there's no barrier after the store.
1004   //    We want to guarantee the same behavior as on platforms with total store
1005   //    order, although this is not required by the Java memory model.
1006   //    In this case, we want to enforce visibility of volatile field
1007   //    initializations which are performed in constructors.
1008   //    So as with finals, we add a barrier here.
1009   //
1010   // "All bets are off" unless the first publication occurs after a
1011   // normal return from the constructor.  We do not attempt to detect
1012   // such unusual early publications.  But no barrier is needed on
1013   // exceptional returns, since they cannot publish normally.
1014   //
1015   if (method()->is_object_initializer() &&
1016        (wrote_final() || wrote_stable() ||
1017          (AlwaysSafeConstructors && wrote_fields()) ||
1018          (support_IRIW_for_not_multiple_copy_atomic_cpu && wrote_volatile()))) {
1019     Node* recorded_alloc = alloc_with_final_or_stable();
1020     _exits.insert_mem_bar(UseStoreStoreForCtor ? Op_MemBarStoreStore : Op_MemBarRelease,
1021                           recorded_alloc);
1022 
1023     // If Memory barrier is created for final fields write
1024     // and allocation node does not escape the initialize method,
1025     // then barrier introduced by allocation node can be removed.
1026     if (DoEscapeAnalysis && (recorded_alloc != nullptr)) {
1027       AllocateNode* alloc = AllocateNode::Ideal_allocation(recorded_alloc);
1028       alloc->compute_MemBar_redundancy(method());
1029     }
1030     if (PrintOpto && (Verbose || WizardMode)) {
1031       method()->print_name();
1032       tty->print_cr(" writes finals/@Stable and needs a memory barrier");
1033     }
1034   }
1035 
1036   for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
1037     // transform each slice of the original memphi:
1038     mms.set_memory(_gvn.transform(mms.memory()));
1039   }
1040   // Clean up input MergeMems created by transforming the slices
1041   _gvn.transform(_exits.merged_memory());
1042 
1043   if (tf()->range()->cnt() > TypeFunc::Parms) {
1044     const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
1045     Node*       ret_phi  = _gvn.transform( _exits.argument(0) );
1046     if (!_exits.control()->is_top() && _gvn.type(ret_phi)->empty()) {
1047       // If the type we set for the ret_phi in build_exits() is too optimistic and
1048       // the ret_phi is top now, there's an extremely small chance that it may be due to class
1049       // loading.  It could also be due to an error, so mark this method as not compilable because
1050       // otherwise this could lead to an infinite compile loop.
1051       // In any case, this code path is rarely (and never in my testing) reached.
1052       C->record_method_not_compilable("Can't determine return type.");
1053       return;
1054     }
1055     if (ret_type->isa_int()) {
1056       BasicType ret_bt = method()->return_type()->basic_type();
1057       ret_phi = mask_int_value(ret_phi, ret_bt, &_gvn);
1058     }
1059     _exits.push_node(ret_type->basic_type(), ret_phi);
1060   }
1061 
1062   // Note:  Logic for creating and optimizing the ReturnNode is in Compile.
1063 
1064   // Unlock along the exceptional paths.

1118 
1119 //-----------------------------create_entry_map-------------------------------
1120 // Initialize our parser map to contain the types at method entry.
1121 // For OSR, the map contains a single RawPtr parameter.
1122 // Initial monitor locking for sync. methods is performed by do_method_entry.
1123 SafePointNode* Parse::create_entry_map() {
1124   // Check for really stupid bail-out cases.
1125   uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
1126   if (len >= 32760) {
1127     // Bailout expected, this is a very rare edge case.
1128     C->record_method_not_compilable("too many local variables");
1129     return nullptr;
1130   }
1131 
1132   // clear current replaced nodes that are of no use from here on (map was cloned in build_exits).
1133   _caller->map()->delete_replaced_nodes();
1134 
1135   // If this is an inlined method, we may have to do a receiver null check.
1136   if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
1137     GraphKit kit(_caller);
1138     kit.null_check_receiver_before_call(method());

1139     _caller = kit.transfer_exceptions_into_jvms();

1140     if (kit.stopped()) {
1141       _exits.add_exception_states_from(_caller);
1142       _exits.set_jvms(_caller);
1143       return nullptr;
1144     }
1145   }
1146 
1147   assert(method() != nullptr, "parser must have a method");
1148 
1149   // Create an initial safepoint to hold JVM state during parsing
1150   JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : nullptr);
1151   set_map(new SafePointNode(len, jvms));
1152 
1153   // Capture receiver info for compiled lambda forms.
1154   if (method()->is_compiled_lambda_form()) {
1155     ciInstance* recv_info = _caller->compute_receiver_info(method());
1156     jvms->set_receiver_info(recv_info);
1157   }
1158 
1159   jvms->set_map(map());

1163   SafePointNode* inmap = _caller->map();
1164   assert(inmap != nullptr, "must have inmap");
1165   // In case of null check on receiver above
1166   map()->transfer_replaced_nodes_from(inmap, _new_idx);
1167 
1168   uint i;
1169 
1170   // Pass thru the predefined input parameters.
1171   for (i = 0; i < TypeFunc::Parms; i++) {
1172     map()->init_req(i, inmap->in(i));
1173   }
1174 
1175   if (depth() == 1) {
1176     assert(map()->memory()->Opcode() == Op_Parm, "");
1177     // Insert the memory aliasing node
1178     set_all_memory(reset_memory());
1179   }
1180   assert(merged_memory(), "");
1181 
1182   // Now add the locals which are initially bound to arguments:
1183   uint arg_size = tf()->domain()->cnt();
1184   ensure_stack(arg_size - TypeFunc::Parms);  // OSR methods have funny args
1185   for (i = TypeFunc::Parms; i < arg_size; i++) {
1186     map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
1187   }
1188 
1189   // Clear out the rest of the map (locals and stack)
1190   for (i = arg_size; i < len; i++) {
1191     map()->init_req(i, top());
1192   }
1193 
1194   SafePointNode* entry_map = stop();
1195   return entry_map;
1196 }
1197 
1198 //-----------------------------do_method_entry--------------------------------
1199 // Emit any code needed in the pseudo-block before BCI zero.
1200 // The main thing to do is lock the receiver of a synchronized method.
1201 void Parse::do_method_entry() {
1202   set_parse_bci(InvocationEntryBci); // Pseudo-BCP
1203   set_sp(0);                         // Java Stack Pointer
1204 
1205   NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
1206 






























1207   if (C->env()->dtrace_method_probes()) {
1208     make_dtrace_method_entry(method());
1209   }
1210 
1211 #ifdef ASSERT
1212   // Narrow receiver type when it is too broad for the method being parsed.
1213   if (!method()->is_static()) {
1214     ciInstanceKlass* callee_holder = method()->holder();
1215     const Type* holder_type = TypeInstPtr::make(TypePtr::BotPTR, callee_holder, Type::trust_interfaces);
1216 
1217     Node* receiver_obj = local(0);
1218     const TypeInstPtr* receiver_type = _gvn.type(receiver_obj)->isa_instptr();
1219 
1220     if (receiver_type != nullptr && !receiver_type->higher_equal(holder_type)) {
1221       // Receiver should always be a subtype of callee holder.
1222       // But, since C2 type system doesn't properly track interfaces,
1223       // the invariant can't be expressed in the type system for default methods.
1224       // Example: for unrelated C <: I and D <: I, (C `meet` D) = Object </: I.
1225       assert(callee_holder->is_interface(), "missing subtype check");
1226 

1237 
1238   // If the method is synchronized, we need to construct a lock node, attach
1239   // it to the Start node, and pin it there.
1240   if (method()->is_synchronized()) {
1241     // Insert a FastLockNode right after the Start which takes as arguments
1242     // the current thread pointer, the "this" pointer & the address of the
1243     // stack slot pair used for the lock.  The "this" pointer is a projection
1244     // off the start node, but the locking spot has to be constructed by
1245     // creating a ConLNode of 0, and boxing it with a BoxLockNode.  The BoxLockNode
1246     // becomes the second argument to the FastLockNode call.  The
1247     // FastLockNode becomes the new control parent to pin it to the start.
1248 
1249     // Setup Object Pointer
1250     Node *lock_obj = nullptr;
1251     if (method()->is_static()) {
1252       ciInstance* mirror = _method->holder()->java_mirror();
1253       const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1254       lock_obj = makecon(t_lock);
1255     } else {                  // Else pass the "this" pointer,
1256       lock_obj = local(0);    // which is Parm0 from StartNode

1257     }
1258     // Clear out dead values from the debug info.
1259     kill_dead_locals();
1260     // Build the FastLockNode
1261     _synch_lock = shared_lock(lock_obj);
1262     // Check for bailout in shared_lock
1263     if (failing()) { return; }
1264   }
1265 
1266   // Feed profiling data for parameters to the type system so it can
1267   // propagate it as speculative types
1268   record_profiled_parameters_for_speculation();
1269 }
1270 
1271 //------------------------------init_blocks------------------------------------
1272 // Initialize our parser map to contain the types/monitors at method entry.
1273 void Parse::init_blocks() {
1274   // Create the blocks.
1275   _block_count = flow()->block_count();
1276   _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);

1672 //--------------------handle_missing_successor---------------------------------
1673 void Parse::handle_missing_successor(int target_bci) {
1674 #ifndef PRODUCT
1675   Block* b = block();
1676   int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
1677   tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
1678 #endif
1679   ShouldNotReachHere();
1680 }
1681 
1682 //--------------------------merge_common---------------------------------------
1683 void Parse::merge_common(Parse::Block* target, int pnum) {
1684   if (TraceOptoParse) {
1685     tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
1686   }
1687 
1688   // Zap extra stack slots to top
1689   assert(sp() == target->start_sp(), "");
1690   clean_stack(sp());
1691 


































































1692   if (!target->is_merged()) {   // No prior mapping at this bci
1693     if (TraceOptoParse) { tty->print(" with empty state");  }
1694 
1695     // If this path is dead, do not bother capturing it as a merge.
1696     // It is "as if" we had 1 fewer predecessors from the beginning.
1697     if (stopped()) {
1698       if (TraceOptoParse)  tty->print_cr(", but path is dead and doesn't count");
1699       return;
1700     }
1701 
1702     // Make a region if we know there are multiple or unpredictable inputs.
1703     // (Also, if this is a plain fall-through, we might see another region,
1704     // which must not be allowed into this block's map.)
1705     if (pnum > PhiNode::Input         // Known multiple inputs.
1706         || target->is_handler()       // These have unpredictable inputs.
1707         || target->is_loop_head()     // Known multiple inputs
1708         || control()->is_Region()) {  // We must hide this guy.
1709 
1710       int current_bci = bci();
1711       set_parse_bci(target->start()); // Set target bci

1726       record_for_igvn(r);
1727       // zap all inputs to null for debugging (done in Node(uint) constructor)
1728       // for (int j = 1; j < edges+1; j++) { r->init_req(j, nullptr); }
1729       r->init_req(pnum, control());
1730       set_control(r);
1731       target->copy_irreducible_status_to(r, jvms());
1732       set_parse_bci(current_bci); // Restore bci
1733     }
1734 
1735     // Convert the existing Parser mapping into a mapping at this bci.
1736     store_state_to(target);
1737     assert(target->is_merged(), "do not come here twice");
1738 
1739   } else {                      // Prior mapping at this bci
1740     if (TraceOptoParse) {  tty->print(" with previous state"); }
1741 #ifdef ASSERT
1742     if (target->is_SEL_head()) {
1743       target->mark_merged_backedge(block());
1744     }
1745 #endif

1746     // We must not manufacture more phis if the target is already parsed.
1747     bool nophi = target->is_parsed();
1748 
1749     SafePointNode* newin = map();// Hang on to incoming mapping
1750     Block* save_block = block(); // Hang on to incoming block;
1751     load_state_from(target);    // Get prior mapping
1752 
1753     assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1754     assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1755     assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1756     assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1757 
1758     // Iterate over my current mapping and the old mapping.
1759     // Where different, insert Phi functions.
1760     // Use any existing Phi functions.
1761     assert(control()->is_Region(), "must be merging to a region");
1762     RegionNode* r = control()->as_Region();
1763 
1764     // Compute where to merge into
1765     // Merge incoming control path
1766     r->init_req(pnum, newin->control());
1767 
1768     if (pnum == 1) {            // Last merge for this Region?
1769       if (!block()->flow()->is_irreducible_loop_secondary_entry()) {
1770         Node* result = _gvn.transform(r);
1771         if (r != result && TraceOptoParse) {
1772           tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1773         }
1774       }
1775       record_for_igvn(r);
1776     }
1777 
1778     // Update all the non-control inputs to map:
1779     assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1780     bool check_elide_phi = target->is_SEL_backedge(save_block);

1781     for (uint j = 1; j < newin->req(); j++) {
1782       Node* m = map()->in(j);   // Current state of target.
1783       Node* n = newin->in(j);   // Incoming change to target state.
1784       PhiNode* phi;
1785       if (m->is_Phi() && m->as_Phi()->region() == r)
1786         phi = m->as_Phi();
1787       else


1788         phi = nullptr;

1789       if (m != n) {             // Different; must merge
1790         switch (j) {
1791         // Frame pointer and Return Address never changes
1792         case TypeFunc::FramePtr:// Drop m, use the original value
1793         case TypeFunc::ReturnAdr:
1794           break;
1795         case TypeFunc::Memory:  // Merge inputs to the MergeMem node
1796           assert(phi == nullptr, "the merge contains phis, not vice versa");
1797           merge_memory_edges(n->as_MergeMem(), pnum, nophi);
1798           continue;
1799         default:                // All normal stuff
1800           if (phi == nullptr) {
1801             const JVMState* jvms = map()->jvms();
1802             if (EliminateNestedLocks &&
1803                 jvms->is_mon(j) && jvms->is_monitor_box(j)) {
1804               // BoxLock nodes are not commoning when EliminateNestedLocks is on.
1805               // Use old BoxLock node as merged box.
1806               assert(newin->jvms()->is_monitor_box(j), "sanity");
1807               // This assert also tests that nodes are BoxLock.
1808               assert(BoxLockNode::same_slot(n, m), "sanity");

1815                 // Incremental Inlining before EA and Macro nodes elimination.
1816                 //
1817                 // Incremental Inlining is executed after IGVN optimizations
1818                 // during which BoxLock can be marked as Coarsened.
1819                 old_box->set_coarsened(); // Verifies state
1820                 old_box->set_unbalanced();
1821               }
1822               C->gvn_replace_by(n, m);
1823             } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
1824               phi = ensure_phi(j, nophi);
1825             }
1826           }
1827           break;
1828         }
1829       }
1830       // At this point, n might be top if:
1831       //  - there is no phi (because TypeFlow detected a conflict), or
1832       //  - the corresponding control edges is top (a dead incoming path)
1833       // It is a bug if we create a phi which sees a garbage value on a live path.
1834 
1835       if (phi != nullptr) {

























1836         assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
1837         assert(phi->region() == r, "");
1838         phi->set_req(pnum, n);  // Then add 'n' to the merge
1839         if (pnum == PhiNode::Input) {
1840           // Last merge for this Phi.
1841           // So far, Phis have had a reasonable type from ciTypeFlow.
1842           // Now _gvn will join that with the meet of current inputs.
1843           // BOTTOM is never permissible here, 'cause pessimistically
1844           // Phis of pointers cannot lose the basic pointer type.
1845           DEBUG_ONLY(const Type* bt1 = phi->bottom_type());
1846           assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
1847           map()->set_req(j, _gvn.transform(phi));
1848           DEBUG_ONLY(const Type* bt2 = phi->bottom_type());
1849           assert(bt2->higher_equal_speculative(bt1), "must be consistent with type-flow");
1850           record_for_igvn(phi);
1851         }
1852       }
1853     } // End of for all values to be merged
1854 
1855     if (pnum == PhiNode::Input &&
1856         !r->in(0)) {         // The occasional useless Region
1857       assert(control() == r, "");
1858       set_control(r->nonnull_req());
1859     }
1860 
1861     map()->merge_replaced_nodes_with(newin);
1862 
1863     // newin has been subsumed into the lazy merge, and is now dead.
1864     set_block(save_block);
1865 
1866     stop();                     // done with this guy, for now
1867   }
1868 
1869   if (TraceOptoParse) {
1870     tty->print_cr(" on path %d", pnum);
1871   }
1872 
1873   // Done with this parser state.
1874   assert(stopped(), "");
1875 }
1876 

1988 
1989   // Add new path to the region.
1990   uint pnum = r->req();
1991   r->add_req(nullptr);
1992 
1993   for (uint i = 1; i < map->req(); i++) {
1994     Node* n = map->in(i);
1995     if (i == TypeFunc::Memory) {
1996       // Ensure a phi on all currently known memories.
1997       for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
1998         Node* phi = mms.memory();
1999         if (phi->is_Phi() && phi->as_Phi()->region() == r) {
2000           assert(phi->req() == pnum, "must be same size as region");
2001           phi->add_req(nullptr);
2002         }
2003       }
2004     } else {
2005       if (n->is_Phi() && n->as_Phi()->region() == r) {
2006         assert(n->req() == pnum, "must be same size as region");
2007         n->add_req(nullptr);


2008       }
2009     }
2010   }
2011 
2012   return pnum;
2013 }
2014 
2015 //------------------------------ensure_phi-------------------------------------
2016 // Turn the idx'th entry of the current map into a Phi
2017 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
2018   SafePointNode* map = this->map();
2019   Node* region = map->control();
2020   assert(region->is_Region(), "");
2021 
2022   Node* o = map->in(idx);
2023   assert(o != nullptr, "");
2024 
2025   if (o == top())  return nullptr; // TOP always merges into TOP
2026 
2027   if (o->is_Phi() && o->as_Phi()->region() == region) {
2028     return o->as_Phi();
2029   }




2030 
2031   // Now use a Phi here for merging
2032   assert(!nocreate, "Cannot build a phi for a block already parsed.");
2033   const JVMState* jvms = map->jvms();
2034   const Type* t = nullptr;
2035   if (jvms->is_loc(idx)) {
2036     t = block()->local_type_at(idx - jvms->locoff());
2037   } else if (jvms->is_stk(idx)) {
2038     t = block()->stack_type_at(idx - jvms->stkoff());
2039   } else if (jvms->is_mon(idx)) {
2040     assert(!jvms->is_monitor_box(idx), "no phis for boxes");
2041     t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
2042   } else if ((uint)idx < TypeFunc::Parms) {
2043     t = o->bottom_type();  // Type::RETURN_ADDRESS or such-like.
2044   } else {
2045     assert(false, "no type information for this phi");
2046   }
2047 
2048   // If the type falls to bottom, then this must be a local that
2049   // is mixing ints and oops or some such.  Forcing it to top
2050   // makes it go dead.
2051   if (t == Type::BOTTOM) {
2052     map->set_req(idx, top());
2053     return nullptr;
2054   }
2055 
2056   // Do not create phis for top either.
2057   // A top on a non-null control flow must be an unused even after the.phi.
2058   if (t == Type::TOP || t == Type::HALF) {
2059     map->set_req(idx, top());
2060     return nullptr;
2061   }
2062 
2063   PhiNode* phi = PhiNode::make(region, o, t);
2064   gvn().set_type(phi, t);
2065   if (C->do_escape_analysis()) record_for_igvn(phi);
2066   map->set_req(idx, phi);
2067   return phi;









2068 }
2069 
2070 //--------------------------ensure_memory_phi----------------------------------
2071 // Turn the idx'th slice of the current memory into a Phi
2072 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
2073   MergeMemNode* mem = merged_memory();
2074   Node* region = control();
2075   assert(region->is_Region(), "");
2076 
2077   Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
2078   assert(o != nullptr && o != top(), "");
2079 
2080   PhiNode* phi;
2081   if (o->is_Phi() && o->as_Phi()->region() == region) {
2082     phi = o->as_Phi();
2083     if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
2084       // clone the shared base memory phi to make a new memory split
2085       assert(!nocreate, "Cannot build a phi for a block already parsed.");
2086       const Type* t = phi->bottom_type();
2087       const TypePtr* adr_type = C->get_adr_type(idx);

2177 // Add check to deoptimize once holder klass is fully initialized.
2178 void Parse::clinit_deopt() {
2179   assert(C->has_method(), "only for normal compilations");
2180   assert(depth() == 1, "only for main compiled method");
2181   assert(is_normal_parse(), "no barrier needed on osr entry");
2182   assert(!method()->holder()->is_not_initialized(), "initialization should have been started");
2183 
2184   set_parse_bci(0);
2185 
2186   Node* holder = makecon(TypeKlassPtr::make(method()->holder(), Type::trust_interfaces));
2187   guard_klass_being_initialized(holder);
2188 }
2189 
2190 //------------------------------return_current---------------------------------
2191 // Append current _map to _exit_return
2192 void Parse::return_current(Node* value) {
2193   if (method()->intrinsic_id() == vmIntrinsics::_Object_init) {
2194     call_register_finalizer();
2195   }
2196 


































2197   // Do not set_parse_bci, so that return goo is credited to the return insn.
2198   set_bci(InvocationEntryBci);
2199   if (method()->is_synchronized()) {
2200     shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
2201   }
2202   if (C->env()->dtrace_method_probes()) {
2203     make_dtrace_method_exit(method());
2204   }

2205   SafePointNode* exit_return = _exits.map();
2206   exit_return->in( TypeFunc::Control  )->add_req( control() );
2207   exit_return->in( TypeFunc::I_O      )->add_req( i_o    () );
2208   Node *mem = exit_return->in( TypeFunc::Memory   );
2209   for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
2210     if (mms.is_empty()) {
2211       // get a copy of the base memory, and patch just this one input
2212       const TypePtr* adr_type = mms.adr_type(C);
2213       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
2214       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
2215       gvn().set_type_bottom(phi);
2216       phi->del_req(phi->req()-1);  // prepare to re-patch
2217       mms.set_memory(phi);
2218     }
2219     mms.memory()->add_req(mms.memory2());
2220   }
2221 
2222   // frame pointer is always same, already captured
2223   if (value != nullptr) {
2224     // If returning oops to an interface-return, there is a silent free
2225     // cast from oop to interface allowed by the Verifier.  Make it explicit
2226     // here.
2227     Node* phi = _exits.argument(0);
2228     phi->add_req(value);
2229   }
2230 
2231   if (_first_return) {
2232     _exits.map()->transfer_replaced_nodes_from(map(), _new_idx);
2233     _first_return = false;
2234   } else {
2235     _exits.map()->merge_replaced_nodes_with(map());
2236   }
2237 
2238   stop_and_kill_map();          // This CFG path dies here
2239 }
2240 
2241 
2242 //------------------------------add_safepoint----------------------------------
2243 void Parse::add_safepoint() {
2244   uint parms = TypeFunc::Parms+1;
2245 
2246   // Clear out dead values from the debug info.
2247   kill_dead_locals();
2248 
2249   // Clone the JVM State
2250   SafePointNode *sfpnt = new SafePointNode(parms, nullptr);

  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 "compiler/compileLog.hpp"
  26 #include "interpreter/linkResolver.hpp"
  27 #include "memory/resourceArea.hpp"
  28 #include "oops/method.hpp"
  29 #include "opto/addnode.hpp"
  30 #include "opto/c2compiler.hpp"
  31 #include "opto/castnode.hpp"
  32 #include "opto/convertnode.hpp"
  33 #include "opto/idealGraphPrinter.hpp"
  34 #include "opto/inlinetypenode.hpp"
  35 #include "opto/locknode.hpp"
  36 #include "opto/memnode.hpp"
  37 #include "opto/opaquenode.hpp"
  38 #include "opto/parse.hpp"
  39 #include "opto/rootnode.hpp"
  40 #include "opto/runtime.hpp"
  41 #include "opto/type.hpp"
  42 #include "runtime/handles.inline.hpp"
  43 #include "runtime/safepointMechanism.hpp"
  44 #include "runtime/sharedRuntime.hpp"
  45 #include "utilities/bitMap.inline.hpp"
  46 #include "utilities/copy.hpp"
  47 
  48 // Static array so we can figure out which bytecodes stop us from compiling
  49 // the most. Some of the non-static variables are needed in bytecodeInfo.cpp
  50 // and eventually should be encapsulated in a proper class (gri 8/18/98).
  51 
  52 #ifndef PRODUCT
  53 uint nodes_created             = 0;
  54 uint methods_parsed            = 0;

  86   }
  87   if (all_null_checks_found) {
  88     tty->print_cr("%u made implicit (%2u%%)", implicit_null_checks,
  89                   (100*implicit_null_checks)/all_null_checks_found);
  90   }
  91   if (SharedRuntime::_implicit_null_throws) {
  92     tty->print_cr("%u implicit null exceptions at runtime",
  93                   SharedRuntime::_implicit_null_throws);
  94   }
  95 
  96   if (PrintParseStatistics && BytecodeParseHistogram::initialized()) {
  97     BytecodeParseHistogram::print();
  98   }
  99 }
 100 #endif
 101 
 102 //------------------------------ON STACK REPLACEMENT---------------------------
 103 
 104 // Construct a node which can be used to get incoming state for
 105 // on stack replacement.
 106 Node* Parse::fetch_interpreter_state(int index,
 107                                      const Type* type,
 108                                      Node* local_addrs,
 109                                      Node* local_addrs_base) {
 110   BasicType bt = type->basic_type();
 111   if (type == TypePtr::NULL_PTR) {
 112     // Ptr types are mixed together with T_ADDRESS but nullptr is
 113     // really for T_OBJECT types so correct it.
 114     bt = T_OBJECT;
 115   }
 116   Node *mem = memory(Compile::AliasIdxRaw);
 117   Node *adr = basic_plus_adr( local_addrs_base, local_addrs, -index*wordSize );
 118   Node *ctl = control();
 119 
 120   // Very similar to LoadNode::make, except we handle un-aligned longs and
 121   // doubles on Sparc.  Intel can handle them just fine directly.
 122   Node *l = nullptr;
 123   switch (bt) {                // Signature is flattened
 124   case T_INT:     l = new LoadINode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInt::INT,        MemNode::unordered); break;
 125   case T_FLOAT:   l = new LoadFNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::FLOAT,         MemNode::unordered); break;
 126   case T_ADDRESS: l = new LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM,  MemNode::unordered); break;
 127   case T_OBJECT:  l = new LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInstPtr::BOTTOM, MemNode::unordered); break;
 128   case T_LONG:
 129   case T_DOUBLE: {
 130     // Since arguments are in reverse order, the argument address 'adr'
 131     // refers to the back half of the long/double.  Recompute adr.
 132     adr = basic_plus_adr(local_addrs_base, local_addrs, -(index+1)*wordSize);
 133     if (Matcher::misaligned_doubles_ok) {
 134       l = (bt == T_DOUBLE)
 135         ? (Node*)new LoadDNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::DOUBLE, MemNode::unordered)
 136         : (Node*)new LoadLNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeLong::LONG, MemNode::unordered);
 137     } else {
 138       l = (bt == T_DOUBLE)
 139         ? (Node*)new LoadD_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered)
 140         : (Node*)new LoadL_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered);
 141     }
 142     break;
 143   }
 144   default: ShouldNotReachHere();
 145   }
 146   return _gvn.transform(l);
 147 }
 148 
 149 // Helper routine to prevent the interpreter from handing
 150 // unexpected typestate to an OSR method.
 151 // The Node l is a value newly dug out of the interpreter frame.
 152 // The type is the type predicted by ciTypeFlow.  Note that it is
 153 // not a general type, but can only come from Type::get_typeflow_type.
 154 // The safepoint is a map which will feed an uncommon trap.
 155 Node* Parse::check_interpreter_type(Node* l, const Type* type,
 156                                     SafePointNode* &bad_type_exit, bool is_early_larval) {

 157   const TypeOopPtr* tp = type->isa_oopptr();
 158 
 159   // TypeFlow may assert null-ness if a type appears unloaded.
 160   if (type == TypePtr::NULL_PTR ||
 161       (tp != nullptr && !tp->is_loaded())) {
 162     // Value must be null, not a real oop.
 163     Node* chk = _gvn.transform( new CmpPNode(l, null()) );
 164     Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
 165     IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
 166     set_control(_gvn.transform( new IfTrueNode(iff) ));
 167     Node* bad_type = _gvn.transform( new IfFalseNode(iff) );
 168     bad_type_exit->control()->add_req(bad_type);
 169     l = null();
 170   }
 171 
 172   // Typeflow can also cut off paths from the CFG, based on
 173   // types which appear unloaded, or call sites which appear unlinked.
 174   // When paths are cut off, values at later merge points can rise
 175   // toward more specific classes.  Make sure these specific classes
 176   // are still in effect.
 177   if (tp != nullptr && !tp->is_same_java_type_as(TypeInstPtr::BOTTOM)) {
 178     // TypeFlow asserted a specific object type.  Value must have that type.
 179     Node* bad_type_ctrl = nullptr;
 180     if (tp->is_inlinetypeptr() && !tp->maybe_null()) {
 181       // Check inline types for null here to prevent checkcast from adding an
 182       // exception state before the bytecode entry (use 'bad_type_ctrl' instead).
 183       l = null_check_oop(l, &bad_type_ctrl);
 184       bad_type_exit->control()->add_req(bad_type_ctrl);
 185     }
 186 
 187     l = gen_checkcast(l, makecon(tp->as_klass_type()->cast_to_exactness(true)), &bad_type_ctrl, false, is_early_larval);
 188     bad_type_exit->control()->add_req(bad_type_ctrl);
 189   }
 190 
 191   assert(_gvn.type(l)->higher_equal(type), "must constrain OSR typestate");
 192   return l;
 193 }
 194 
 195 // Helper routine which sets up elements of the initial parser map when
 196 // performing a parse for on stack replacement.  Add values into map.
 197 // The only parameter contains the address of a interpreter arguments.
 198 void Parse::load_interpreter_state(Node* osr_buf) {
 199   int index;
 200   int max_locals = jvms()->loc_size();
 201   int max_stack  = jvms()->stk_size();
 202 

 203   // Mismatch between method and jvms can occur since map briefly held
 204   // an OSR entry state (which takes up one RawPtr word).
 205   assert(max_locals == method()->max_locals(), "sanity");
 206   assert(max_stack  >= method()->max_stack(),  "sanity");
 207   assert((int)jvms()->endoff() == TypeFunc::Parms + max_locals + max_stack, "sanity");
 208   assert((int)jvms()->endoff() == (int)map()->req(), "sanity");
 209 
 210   // Find the start block.
 211   Block* osr_block = start_block();
 212   assert(osr_block->start() == osr_bci(), "sanity");
 213 
 214   // Set initial BCI.
 215   set_parse_bci(osr_block->start());
 216 
 217   // Set initial stack depth.
 218   set_sp(osr_block->start_sp());
 219 
 220   // Check bailouts.  We currently do not perform on stack replacement
 221   // of loops in catch blocks or loops which branch with a non-empty stack.
 222   if (sp() != 0) {

 237   for (index = 0; index < mcnt; index++) {
 238     // Make a BoxLockNode for the monitor.
 239     BoxLockNode* osr_box = new BoxLockNode(next_monitor());
 240     // Check for bailout after new BoxLockNode
 241     if (failing()) { return; }
 242 
 243     // This OSR locking region is unbalanced because it does not have Lock node:
 244     // locking was done in Interpreter.
 245     // This is similar to Coarsened case when Lock node is eliminated
 246     // and as result the region is marked as Unbalanced.
 247 
 248     // Emulate Coarsened state transition from Regular to Unbalanced.
 249     osr_box->set_coarsened();
 250     osr_box->set_unbalanced();
 251 
 252     Node* box = _gvn.transform(osr_box);
 253 
 254     // Displaced headers and locked objects are interleaved in the
 255     // temp OSR buffer.  We only copy the locked objects out here.
 256     // Fetch the locked object from the OSR temp buffer and copy to our fastlock node.
 257     Node* lock_object = fetch_interpreter_state(index*2, Type::get_const_basic_type(T_OBJECT), monitors_addr, osr_buf);
 258     // Try and copy the displaced header to the BoxNode
 259     Node* displaced_hdr = fetch_interpreter_state((index*2) + 1, Type::get_const_basic_type(T_ADDRESS), monitors_addr, osr_buf);

 260 
 261     store_to_memory(control(), box, displaced_hdr, T_ADDRESS, MemNode::unordered);
 262 
 263     // Build a bogus FastLockNode (no code will be generated) and push the
 264     // monitor into our debug info.
 265     const FastLockNode *flock = _gvn.transform(new FastLockNode( nullptr, lock_object, box ))->as_FastLock();
 266     map()->push_monitor(flock);
 267 
 268     // If the lock is our method synchronization lock, tuck it away in
 269     // _sync_lock for return and rethrow exit paths.
 270     if (index == 0 && method()->is_synchronized()) {
 271       _synch_lock = flock;
 272     }
 273   }
 274 
 275   // Use the raw liveness computation to make sure that unexpected
 276   // values don't propagate into the OSR frame.
 277   MethodLivenessResult live_locals = method()->liveness_at_bci(osr_bci());
 278   if (!live_locals.is_valid()) {
 279     // Degenerate or breakpointed method.

 307         if (C->log() != nullptr) {
 308           C->log()->elem("OSR_mismatch local_index='%d'",index);
 309         }
 310         set_local(index, null());
 311         // and ignore it for the loads
 312         continue;
 313       }
 314     }
 315 
 316     // Filter out TOP, HALF, and BOTTOM.  (Cf. ensure_phi.)
 317     if (type == Type::TOP || type == Type::HALF) {
 318       continue;
 319     }
 320     // If the type falls to bottom, then this must be a local that
 321     // is mixing ints and oops or some such.  Forcing it to top
 322     // makes it go dead.
 323     if (type == Type::BOTTOM) {
 324       continue;
 325     }
 326     // Construct code to access the appropriate local.
 327     Node* value = fetch_interpreter_state(index, type, locals_addr, osr_buf);






 328     set_local(index, value);
 329   }
 330 
 331   // Extract the needed stack entries from the interpreter frame.
 332   for (index = 0; index < sp(); index++) {
 333     const Type *type = osr_block->stack_type_at(index);
 334     if (type != Type::TOP) {
 335       // Currently the compiler bails out when attempting to on stack replace
 336       // at a bci with a non-empty stack.  We should not reach here.
 337       ShouldNotReachHere();
 338     }
 339   }
 340 
 341   // End the OSR migration
 342   make_runtime_call(RC_LEAF, OptoRuntime::osr_end_Type(),
 343                     CAST_FROM_FN_PTR(address, SharedRuntime::OSR_migration_end),
 344                     "OSR_migration_end", TypeRawPtr::BOTTOM,
 345                     osr_buf);
 346 
 347   // Now that the interpreter state is loaded, make sure it will match

 358     if (type->isa_oopptr() != nullptr) {
 359       if (!live_oops.at(index)) {
 360         // skip type check for dead oops
 361         continue;
 362       }
 363     }
 364     if (osr_block->flow()->local_type_at(index)->is_return_address()) {
 365       // In our current system it's illegal for jsr addresses to be
 366       // live into an OSR entry point because the compiler performs
 367       // inlining of jsrs.  ciTypeFlow has a bailout that detect this
 368       // case and aborts the compile if addresses are live into an OSR
 369       // entry point.  Because of that we can assume that any address
 370       // locals at the OSR entry point are dead.  Method liveness
 371       // isn't precise enough to figure out that they are dead in all
 372       // cases so simply skip checking address locals all
 373       // together. Any type check is guaranteed to fail since the
 374       // interpreter type is the result of a load which might have any
 375       // value and the expected type is a constant.
 376       continue;
 377     }
 378     bool is_early_larval = osr_block->flow()->local_type_at(index)->is_early_larval();
 379     set_local(index, check_interpreter_type(l, type, bad_type_exit, is_early_larval));
 380   }
 381 
 382   for (index = 0; index < sp(); index++) {
 383     if (stopped())  break;
 384     Node* l = stack(index);
 385     if (l->is_top())  continue;  // nothing here
 386     const Type *type = osr_block->stack_type_at(index);
 387     bool is_early_larval = osr_block->flow()->stack_type_at(index)->is_early_larval();
 388     set_stack(index, check_interpreter_type(l, type, bad_type_exit, is_early_larval));
 389   }
 390 
 391   if (bad_type_exit->control()->req() > 1) {
 392     // Build an uncommon trap here, if any inputs can be unexpected.
 393     bad_type_exit->set_control(_gvn.transform( bad_type_exit->control() ));
 394     record_for_igvn(bad_type_exit->control());
 395     SafePointNode* types_are_good = map();
 396     set_map(bad_type_exit);
 397     // The unexpected type happens because a new edge is active
 398     // in the CFG, which typeflow had previously ignored.
 399     // E.g., Object x = coldAtFirst() && notReached()? "str": new Integer(123).
 400     // This x will be typed as Integer if notReached is not yet linked.
 401     // It could also happen due to a problem in ciTypeFlow analysis.
 402     uncommon_trap(Deoptimization::Reason_constraint,
 403                   Deoptimization::Action_reinterpret);
 404     set_map(types_are_good);
 405   }
 406 }
 407 
 408 //------------------------------Parse------------------------------------------

 509   // either breakpoint setting or hotswapping of methods may
 510   // cause deoptimization.
 511   if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
 512     C->dependencies()->assert_evol_method(method());
 513   }
 514 
 515   NOT_PRODUCT(methods_seen++);
 516 
 517   // Do some special top-level things.
 518   if (depth() == 1 && C->is_osr_compilation()) {
 519     _tf = C->tf();     // the OSR entry type is different
 520     _entry_bci = C->entry_bci();
 521     _flow = method()->get_osr_flow_analysis(osr_bci());
 522   } else {
 523     _tf = TypeFunc::make(method());
 524     _entry_bci = InvocationEntryBci;
 525     _flow = method()->get_flow_analysis();
 526   }
 527 
 528   if (_flow->failing()) {
 529     // TODO Adding a trap due to an unloaded return type in ciTypeFlow::StateVector::do_invoke
 530     // can lead to this. Re-enable once 8284443 is fixed.
 531     //assert(false, "type flow analysis failed during parsing");
 532     C->record_method_not_compilable(_flow->failure_reason());
 533 #ifndef PRODUCT
 534       if (PrintOpto && (Verbose || WizardMode)) {
 535         if (is_osr_parse()) {
 536           tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
 537         } else {
 538           tty->print_cr("type flow bailout: %s", _flow->failure_reason());
 539         }
 540         if (Verbose) {
 541           method()->print();
 542           method()->print_codes();
 543           _flow->print();
 544         }
 545       }
 546 #endif
 547   }
 548 
 549 #ifdef ASSERT
 550   if (depth() == 1) {
 551     assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");

 602     load_interpreter_state(osr_buf);
 603   } else {
 604     set_map(entry_map);
 605     do_method_entry();
 606   }
 607 
 608   if (depth() == 1 && !failing()) {
 609     if (C->clinit_barrier_on_entry()) {
 610       // Add check to deoptimize the nmethod once the holder class is fully initialized
 611       clinit_deopt();
 612     }
 613   }
 614 
 615   // Check for bailouts during method entry.
 616   if (failing()) {
 617     if (log)  log->done("parse");
 618     C->set_default_node_notes(caller_nn);
 619     return;
 620   }
 621 
 622   // Handle inline type arguments
 623   int arg_size = method()->arg_size();
 624   for (int i = 0; i < arg_size; i++) {
 625     Node* parm = local(i);
 626     const Type* t = _gvn.type(parm);
 627     if (t->is_inlinetypeptr()) {
 628       // If the parameter is a value object, try to scalarize it if we know that it is unrestricted (not early larval)
 629       // Parameters are non-larval except the receiver of a constructor, which must be an early larval object.
 630       if (!(method()->is_object_constructor() && i == 0)) {
 631         // Create InlineTypeNode from the oop and replace the parameter
 632         Node* vt = InlineTypeNode::make_from_oop(this, parm, t->inline_klass());
 633         replace_in_map(parm, vt);
 634       }
 635     } else if (UseTypeSpeculation && (i == (arg_size - 1)) && !is_osr_parse() && method()->has_vararg() &&
 636                t->isa_aryptr() != nullptr && !t->is_aryptr()->is_null_free() && !t->is_aryptr()->is_flat() &&
 637                (!t->is_aryptr()->is_not_null_free() || !t->is_aryptr()->is_not_flat())) {
 638       // Speculate on varargs Object array being not null-free and not flat
 639       const TypePtr* spec_type = t->speculative();
 640       spec_type = (spec_type != nullptr && spec_type->isa_aryptr() != nullptr) ? spec_type : t->is_aryptr();
 641       spec_type = spec_type->remove_speculative()->is_aryptr()->cast_to_not_null_free()->cast_to_not_flat();
 642       spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::Offset::bottom, TypeOopPtr::InstanceBot, spec_type);
 643       Node* cast = _gvn.transform(new CheckCastPPNode(control(), parm, t->join_speculative(spec_type)));
 644       replace_in_map(parm, cast);
 645     }
 646   }
 647 
 648   entry_map = map();  // capture any changes performed by method setup code
 649   assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");
 650 
 651   // We begin parsing as if we have just encountered a jump to the
 652   // method entry.
 653   Block* entry_block = start_block();
 654   assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
 655   set_map_clone(entry_map);
 656   merge_common(entry_block, entry_block->next_path_num());
 657 
 658 #ifndef PRODUCT
 659   BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
 660   set_parse_histogram( parse_histogram_obj );
 661 #endif
 662 
 663   // Parse all the basic blocks.
 664   do_all_blocks();
 665 
 666   // Check for bailouts during conversion to graph
 667   if (failing()) {

 813 void Parse::build_exits() {
 814   // make a clone of caller to prevent sharing of side-effects
 815   _exits.set_map(_exits.clone_map());
 816   _exits.clean_stack(_exits.sp());
 817   _exits.sync_jvms();
 818 
 819   RegionNode* region = new RegionNode(1);
 820   record_for_igvn(region);
 821   gvn().set_type_bottom(region);
 822   _exits.set_control(region);
 823 
 824   // Note:  iophi and memphi are not transformed until do_exits.
 825   Node* iophi  = new PhiNode(region, Type::ABIO);
 826   Node* memphi = new PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
 827   gvn().set_type_bottom(iophi);
 828   gvn().set_type_bottom(memphi);
 829   _exits.set_i_o(iophi);
 830   _exits.set_all_memory(memphi);
 831 
 832   // Add a return value to the exit state.  (Do not push it yet.)
 833   if (tf()->range_sig()->cnt() > TypeFunc::Parms) {
 834     const Type* ret_type = tf()->range_sig()->field_at(TypeFunc::Parms);
 835     if (ret_type->isa_int()) {
 836       BasicType ret_bt = method()->return_type()->basic_type();
 837       if (ret_bt == T_BOOLEAN ||
 838           ret_bt == T_CHAR ||
 839           ret_bt == T_BYTE ||
 840           ret_bt == T_SHORT) {
 841         ret_type = TypeInt::INT;
 842       }
 843     }
 844 
 845     // Don't "bind" an unloaded return klass to the ret_phi. If the klass
 846     // becomes loaded during the subsequent parsing, the loaded and unloaded
 847     // types will not join when we transform and push in do_exits().
 848     const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
 849     if (ret_oop_type && !ret_oop_type->is_loaded()) {
 850       ret_type = TypeOopPtr::BOTTOM;
 851     }
 852     int         ret_size = type2size[ret_type->basic_type()];
 853     Node*       ret_phi  = new PhiNode(region, ret_type);
 854     gvn().set_type_bottom(ret_phi);
 855     _exits.ensure_stack(ret_size);
 856     assert((int)(tf()->range_sig()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
 857     assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
 858     _exits.set_argument(0, ret_phi);  // here is where the parser finds it
 859     // Note:  ret_phi is not yet pushed, until do_exits.
 860   }
 861 }
 862 

 863 //----------------------------build_start_state-------------------------------
 864 // Construct a state which contains only the incoming arguments from an
 865 // unknown caller.  The method & bci will be null & InvocationEntryBci.
 866 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
 867   int        arg_size = tf->domain_sig()->cnt();
 868   int        max_size = MAX2(arg_size, (int)tf->range_cc()->cnt());
 869   JVMState*  jvms     = new (this) JVMState(max_size - TypeFunc::Parms);
 870   SafePointNode* map  = new SafePointNode(max_size, jvms);
 871   jvms->set_map(map);
 872   record_for_igvn(map);
 873   assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
 874   Node_Notes* old_nn = default_node_notes();
 875   if (old_nn != nullptr && has_method()) {
 876     Node_Notes* entry_nn = old_nn->clone(this);
 877     JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
 878     entry_jvms->set_offsets(0);
 879     entry_jvms->set_bci(entry_bci());
 880     entry_nn->set_jvms(entry_jvms);
 881     set_default_node_notes(entry_nn);
 882   }
 883   PhaseGVN& gvn = *initial_gvn();
 884   uint i = 0;
 885   int arg_num = 0;
 886   for (uint j = 0; i < (uint)arg_size; i++) {
 887     const Type* t = tf->domain_sig()->field_at(i);
 888     Node* parm = nullptr;
 889     if (t->is_inlinetypeptr() && method()->is_scalarized_arg(arg_num)) {
 890       // Inline type arguments are not passed by reference: we get an argument per
 891       // field of the inline type. Build InlineTypeNodes from the inline type arguments.
 892       GraphKit kit(jvms, &gvn);
 893       kit.set_control(map->control());
 894       Node* old_mem = map->memory();
 895       // Use immutable memory for inline type loads and restore it below
 896       kit.set_all_memory(C->immutable_memory());
 897       parm = InlineTypeNode::make_from_multi(&kit, start, t->inline_klass(), j, /* in= */ true, /* null_free= */ !t->maybe_null());
 898       map->set_control(kit.control());
 899       map->set_memory(old_mem);
 900     } else {
 901       parm = gvn.transform(new ParmNode(start, j++));
 902     }
 903     map->init_req(i, parm);
 904     // Record all these guys for later GVN.
 905     record_for_igvn(parm);
 906     if (i >= TypeFunc::Parms && t != Type::HALF) {
 907       arg_num++;
 908     }
 909   }
 910   for (; i < map->req(); i++) {
 911     map->init_req(i, top());
 912   }
 913   assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
 914   set_default_node_notes(old_nn);

 915   return jvms;
 916 }
 917 
 918 //-----------------------------make_node_notes---------------------------------
 919 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
 920   if (caller_nn == nullptr)  return nullptr;
 921   Node_Notes* nn = caller_nn->clone(C);
 922   JVMState* caller_jvms = nn->jvms();
 923   JVMState* jvms = new (C) JVMState(method(), caller_jvms);
 924   jvms->set_offsets(0);
 925   jvms->set_bci(_entry_bci);
 926   nn->set_jvms(jvms);
 927   return nn;
 928 }
 929 
 930 
 931 //--------------------------return_values--------------------------------------
 932 void Compile::return_values(JVMState* jvms) {
 933   GraphKit kit(jvms);
 934   Node* ret = new ReturnNode(TypeFunc::Parms,
 935                              kit.control(),
 936                              kit.i_o(),
 937                              kit.reset_memory(),
 938                              kit.frameptr(),
 939                              kit.returnadr());
 940   // Add zero or 1 return values
 941   int ret_size = tf()->range_sig()->cnt() - TypeFunc::Parms;
 942   if (ret_size > 0) {
 943     kit.inc_sp(-ret_size);  // pop the return value(s)
 944     kit.sync_jvms();
 945     Node* res = kit.argument(0);
 946     if (tf()->returns_inline_type_as_fields()) {
 947       // Multiple return values (inline type fields): add as many edges
 948       // to the Return node as returned values.
 949       InlineTypeNode* vt = res->as_InlineType();
 950       ret->add_req_batch(nullptr, tf()->range_cc()->cnt() - TypeFunc::Parms);
 951       if (vt->is_allocated(&kit.gvn()) && !StressCallingConvention) {
 952         ret->init_req(TypeFunc::Parms, vt);
 953       } else {
 954         // Return the tagged klass pointer to signal scalarization to the caller
 955         Node* tagged_klass = vt->tagged_klass(kit.gvn());
 956         // Return null if the inline type is null (null marker field is not set)
 957         Node* conv   = kit.gvn().transform(new ConvI2LNode(vt->get_null_marker()));
 958         Node* shl    = kit.gvn().transform(new LShiftLNode(conv, kit.intcon(63)));
 959         Node* shr    = kit.gvn().transform(new RShiftLNode(shl, kit.intcon(63)));
 960         tagged_klass = kit.gvn().transform(new AndLNode(tagged_klass, shr));
 961         ret->init_req(TypeFunc::Parms, tagged_klass);
 962       }
 963       uint idx = TypeFunc::Parms + 1;
 964       vt->pass_fields(&kit, ret, idx, false, false);
 965     } else {
 966       ret->add_req(res);
 967       // Note:  The second dummy edge is not needed by a ReturnNode.
 968     }
 969   }
 970   // bind it to root
 971   root()->add_req(ret);
 972   record_for_igvn(ret);
 973   initial_gvn()->transform(ret);
 974 }
 975 
 976 //------------------------rethrow_exceptions-----------------------------------
 977 // Bind all exception states in the list into a single RethrowNode.
 978 void Compile::rethrow_exceptions(JVMState* jvms) {
 979   GraphKit kit(jvms);
 980   if (!kit.has_exceptions())  return;  // nothing to generate
 981   // Load my combined exception state into the kit, with all phis transformed:
 982   SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
 983   Node* ex_oop = kit.use_exception_state(ex_map);
 984   RethrowNode* exit = new RethrowNode(kit.control(),
 985                                       kit.i_o(), kit.reset_memory(),
 986                                       kit.frameptr(), kit.returnadr(),
 987                                       // like a return but with exception input
 988                                       ex_oop);

1072   //    to complete, we force all writes to complete.
1073   //
1074   // 2. Experimental VM option is used to force the barrier if any field
1075   //    was written out in the constructor.
1076   //
1077   // 3. On processors which are not CPU_MULTI_COPY_ATOMIC (e.g. PPC64),
1078   //    support_IRIW_for_not_multiple_copy_atomic_cpu selects that
1079   //    MemBarVolatile is used before volatile load instead of after volatile
1080   //    store, so there's no barrier after the store.
1081   //    We want to guarantee the same behavior as on platforms with total store
1082   //    order, although this is not required by the Java memory model.
1083   //    In this case, we want to enforce visibility of volatile field
1084   //    initializations which are performed in constructors.
1085   //    So as with finals, we add a barrier here.
1086   //
1087   // "All bets are off" unless the first publication occurs after a
1088   // normal return from the constructor.  We do not attempt to detect
1089   // such unusual early publications.  But no barrier is needed on
1090   // exceptional returns, since they cannot publish normally.
1091   //
1092   if ((method()->is_object_constructor() || method()->is_class_initializer()) &&
1093        (wrote_final() || wrote_stable() ||
1094          (AlwaysSafeConstructors && wrote_fields()) ||
1095          (support_IRIW_for_not_multiple_copy_atomic_cpu && wrote_volatile()))) {
1096     Node* recorded_alloc = alloc_with_final_or_stable();
1097     _exits.insert_mem_bar(UseStoreStoreForCtor ? Op_MemBarStoreStore : Op_MemBarRelease,
1098                           recorded_alloc);
1099 
1100     // If Memory barrier is created for final fields write
1101     // and allocation node does not escape the initialize method,
1102     // then barrier introduced by allocation node can be removed.
1103     if (DoEscapeAnalysis && (recorded_alloc != nullptr)) {
1104       AllocateNode* alloc = AllocateNode::Ideal_allocation(recorded_alloc);
1105       alloc->compute_MemBar_redundancy(method());
1106     }
1107     if (PrintOpto && (Verbose || WizardMode)) {
1108       method()->print_name();
1109       tty->print_cr(" writes finals/@Stable and needs a memory barrier");
1110     }
1111   }
1112 
1113   for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
1114     // transform each slice of the original memphi:
1115     mms.set_memory(_gvn.transform(mms.memory()));
1116   }
1117   // Clean up input MergeMems created by transforming the slices
1118   _gvn.transform(_exits.merged_memory());
1119 
1120   if (tf()->range_sig()->cnt() > TypeFunc::Parms) {
1121     const Type* ret_type = tf()->range_sig()->field_at(TypeFunc::Parms);
1122     Node*       ret_phi  = _gvn.transform( _exits.argument(0) );
1123     if (!_exits.control()->is_top() && _gvn.type(ret_phi)->empty()) {
1124       // If the type we set for the ret_phi in build_exits() is too optimistic and
1125       // the ret_phi is top now, there's an extremely small chance that it may be due to class
1126       // loading.  It could also be due to an error, so mark this method as not compilable because
1127       // otherwise this could lead to an infinite compile loop.
1128       // In any case, this code path is rarely (and never in my testing) reached.
1129       C->record_method_not_compilable("Can't determine return type.");
1130       return;
1131     }
1132     if (ret_type->isa_int()) {
1133       BasicType ret_bt = method()->return_type()->basic_type();
1134       ret_phi = mask_int_value(ret_phi, ret_bt, &_gvn);
1135     }
1136     _exits.push_node(ret_type->basic_type(), ret_phi);
1137   }
1138 
1139   // Note:  Logic for creating and optimizing the ReturnNode is in Compile.
1140 
1141   // Unlock along the exceptional paths.

1195 
1196 //-----------------------------create_entry_map-------------------------------
1197 // Initialize our parser map to contain the types at method entry.
1198 // For OSR, the map contains a single RawPtr parameter.
1199 // Initial monitor locking for sync. methods is performed by do_method_entry.
1200 SafePointNode* Parse::create_entry_map() {
1201   // Check for really stupid bail-out cases.
1202   uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
1203   if (len >= 32760) {
1204     // Bailout expected, this is a very rare edge case.
1205     C->record_method_not_compilable("too many local variables");
1206     return nullptr;
1207   }
1208 
1209   // clear current replaced nodes that are of no use from here on (map was cloned in build_exits).
1210   _caller->map()->delete_replaced_nodes();
1211 
1212   // If this is an inlined method, we may have to do a receiver null check.
1213   if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
1214     GraphKit kit(_caller);
1215     Node* receiver = kit.argument(0);
1216     Node* null_free = kit.null_check_receiver_before_call(method());
1217     _caller = kit.transfer_exceptions_into_jvms();
1218 
1219     if (kit.stopped()) {
1220       _exits.add_exception_states_from(_caller);
1221       _exits.set_jvms(_caller);
1222       return nullptr;
1223     }
1224   }
1225 
1226   assert(method() != nullptr, "parser must have a method");
1227 
1228   // Create an initial safepoint to hold JVM state during parsing
1229   JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : nullptr);
1230   set_map(new SafePointNode(len, jvms));
1231 
1232   // Capture receiver info for compiled lambda forms.
1233   if (method()->is_compiled_lambda_form()) {
1234     ciInstance* recv_info = _caller->compute_receiver_info(method());
1235     jvms->set_receiver_info(recv_info);
1236   }
1237 
1238   jvms->set_map(map());

1242   SafePointNode* inmap = _caller->map();
1243   assert(inmap != nullptr, "must have inmap");
1244   // In case of null check on receiver above
1245   map()->transfer_replaced_nodes_from(inmap, _new_idx);
1246 
1247   uint i;
1248 
1249   // Pass thru the predefined input parameters.
1250   for (i = 0; i < TypeFunc::Parms; i++) {
1251     map()->init_req(i, inmap->in(i));
1252   }
1253 
1254   if (depth() == 1) {
1255     assert(map()->memory()->Opcode() == Op_Parm, "");
1256     // Insert the memory aliasing node
1257     set_all_memory(reset_memory());
1258   }
1259   assert(merged_memory(), "");
1260 
1261   // Now add the locals which are initially bound to arguments:
1262   uint arg_size = tf()->domain_sig()->cnt();
1263   ensure_stack(arg_size - TypeFunc::Parms);  // OSR methods have funny args
1264   for (i = TypeFunc::Parms; i < arg_size; i++) {
1265     map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
1266   }
1267 
1268   // Clear out the rest of the map (locals and stack)
1269   for (i = arg_size; i < len; i++) {
1270     map()->init_req(i, top());
1271   }
1272 
1273   SafePointNode* entry_map = stop();
1274   return entry_map;
1275 }
1276 
1277 //-----------------------------do_method_entry--------------------------------
1278 // Emit any code needed in the pseudo-block before BCI zero.
1279 // The main thing to do is lock the receiver of a synchronized method.
1280 void Parse::do_method_entry() {
1281   set_parse_bci(InvocationEntryBci); // Pseudo-BCP
1282   set_sp(0);                         // Java Stack Pointer
1283 
1284   NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
1285 
1286   // Check if we need a membar at the beginning of the java.lang.Object
1287   // constructor to satisfy the memory model for strict fields.
1288   if (EnableValhalla && method()->intrinsic_id() == vmIntrinsics::_Object_init) {
1289     Node* receiver_obj = local(0);
1290     const TypeInstPtr* receiver_type = _gvn.type(receiver_obj)->isa_instptr();
1291     // If there's no exact type, check if the declared type has no implementors and add a dependency
1292     const TypeKlassPtr* klass_ptr = receiver_type->as_klass_type(/* try_for_exact= */ true);
1293     ciType* klass = klass_ptr->klass_is_exact() ? klass_ptr->exact_klass() : nullptr;
1294     if (klass != nullptr && klass->is_instance_klass()) {
1295       // Exact receiver type, check if there is a strict field
1296       ciInstanceKlass* holder = klass->as_instance_klass();
1297       for (int i = 0; i < holder->nof_nonstatic_fields(); i++) {
1298         ciField* field = holder->nonstatic_field_at(i);
1299         if (field->is_strict()) {
1300           // Found a strict field, a membar is needed
1301           AllocateNode* alloc = AllocateNode::Ideal_allocation(receiver_obj);
1302           insert_mem_bar(UseStoreStoreForCtor ? Op_MemBarStoreStore : Op_MemBarRelease, receiver_obj);
1303           if (DoEscapeAnalysis && (alloc != nullptr)) {
1304             alloc->compute_MemBar_redundancy(method());
1305           }
1306           break;
1307         }
1308       }
1309     } else if (klass == nullptr) {
1310       // We can't statically determine the type of the receiver and therefore need
1311       // to put a membar here because it could have a strict field.
1312       insert_mem_bar(UseStoreStoreForCtor ? Op_MemBarStoreStore : Op_MemBarRelease);
1313     }
1314   }
1315 
1316   if (C->env()->dtrace_method_probes()) {
1317     make_dtrace_method_entry(method());
1318   }
1319 
1320 #ifdef ASSERT
1321   // Narrow receiver type when it is too broad for the method being parsed.
1322   if (!method()->is_static()) {
1323     ciInstanceKlass* callee_holder = method()->holder();
1324     const Type* holder_type = TypeInstPtr::make(TypePtr::BotPTR, callee_holder, Type::trust_interfaces);
1325 
1326     Node* receiver_obj = local(0);
1327     const TypeInstPtr* receiver_type = _gvn.type(receiver_obj)->isa_instptr();
1328 
1329     if (receiver_type != nullptr && !receiver_type->higher_equal(holder_type)) {
1330       // Receiver should always be a subtype of callee holder.
1331       // But, since C2 type system doesn't properly track interfaces,
1332       // the invariant can't be expressed in the type system for default methods.
1333       // Example: for unrelated C <: I and D <: I, (C `meet` D) = Object </: I.
1334       assert(callee_holder->is_interface(), "missing subtype check");
1335 

1346 
1347   // If the method is synchronized, we need to construct a lock node, attach
1348   // it to the Start node, and pin it there.
1349   if (method()->is_synchronized()) {
1350     // Insert a FastLockNode right after the Start which takes as arguments
1351     // the current thread pointer, the "this" pointer & the address of the
1352     // stack slot pair used for the lock.  The "this" pointer is a projection
1353     // off the start node, but the locking spot has to be constructed by
1354     // creating a ConLNode of 0, and boxing it with a BoxLockNode.  The BoxLockNode
1355     // becomes the second argument to the FastLockNode call.  The
1356     // FastLockNode becomes the new control parent to pin it to the start.
1357 
1358     // Setup Object Pointer
1359     Node *lock_obj = nullptr;
1360     if (method()->is_static()) {
1361       ciInstance* mirror = _method->holder()->java_mirror();
1362       const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1363       lock_obj = makecon(t_lock);
1364     } else {                  // Else pass the "this" pointer,
1365       lock_obj = local(0);    // which is Parm0 from StartNode
1366       assert(!_gvn.type(lock_obj)->make_oopptr()->can_be_inline_type(), "can't be an inline type");
1367     }
1368     // Clear out dead values from the debug info.
1369     kill_dead_locals();
1370     // Build the FastLockNode
1371     _synch_lock = shared_lock(lock_obj);
1372     // Check for bailout in shared_lock
1373     if (failing()) { return; }
1374   }
1375 
1376   // Feed profiling data for parameters to the type system so it can
1377   // propagate it as speculative types
1378   record_profiled_parameters_for_speculation();
1379 }
1380 
1381 //------------------------------init_blocks------------------------------------
1382 // Initialize our parser map to contain the types/monitors at method entry.
1383 void Parse::init_blocks() {
1384   // Create the blocks.
1385   _block_count = flow()->block_count();
1386   _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);

1782 //--------------------handle_missing_successor---------------------------------
1783 void Parse::handle_missing_successor(int target_bci) {
1784 #ifndef PRODUCT
1785   Block* b = block();
1786   int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
1787   tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
1788 #endif
1789   ShouldNotReachHere();
1790 }
1791 
1792 //--------------------------merge_common---------------------------------------
1793 void Parse::merge_common(Parse::Block* target, int pnum) {
1794   if (TraceOptoParse) {
1795     tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
1796   }
1797 
1798   // Zap extra stack slots to top
1799   assert(sp() == target->start_sp(), "");
1800   clean_stack(sp());
1801 
1802   // Check for merge conflicts involving inline types
1803   JVMState* old_jvms = map()->jvms();
1804   int old_bci = bci();
1805   JVMState* tmp_jvms = old_jvms->clone_shallow(C);
1806   tmp_jvms->set_should_reexecute(true);
1807   tmp_jvms->bind_map(map());
1808   // Execution needs to restart a the next bytecode (entry of next
1809   // block)
1810   if (target->is_merged() ||
1811       pnum > PhiNode::Input ||
1812       target->is_handler() ||
1813       target->is_loop_head()) {
1814     set_parse_bci(target->start());
1815     for (uint j = TypeFunc::Parms; j < map()->req(); j++) {
1816       Node* n = map()->in(j);                 // Incoming change to target state.
1817       const Type* t = nullptr;
1818       if (tmp_jvms->is_loc(j)) {
1819         t = target->local_type_at(j - tmp_jvms->locoff());
1820       } else if (tmp_jvms->is_stk(j) && j < (uint)sp() + tmp_jvms->stkoff()) {
1821         t = target->stack_type_at(j - tmp_jvms->stkoff());
1822       }
1823       if (t != nullptr && t != Type::BOTTOM) {
1824         // An object can appear in the JVMS as either an oop or an InlineTypeNode. If the merge is
1825         // an InlineTypeNode, we need all the merge inputs to be InlineTypeNodes. Else, if the
1826         // merge is an oop, each merge input needs to be either an oop or an buffered
1827         // InlineTypeNode.
1828         if (!t->is_inlinetypeptr()) {
1829           // The merge cannot be an InlineTypeNode, ensure the input is buffered if it is an
1830           // InlineTypeNode
1831           if (n->is_InlineType()) {
1832             map()->set_req(j, n->as_InlineType()->buffer(this));
1833           }
1834         } else {
1835           // Since the merge is a value object, it can either be an oop or an InlineTypeNode
1836           if (!target->is_merged()) {
1837             // This is the first processed input of the merge. If it is an InlineTypeNode, the
1838             // merge will be an InlineTypeNode. Else, try to scalarize so the merge can be
1839             // scalarized as well. However, we cannot blindly scalarize an inline type oop here
1840             // since it may be larval
1841             if (!n->is_InlineType() && gvn().type(n)->is_zero_type()) {
1842               // Null constant implies that this is not a larval object
1843               map()->set_req(j, InlineTypeNode::make_null(gvn(), t->inline_klass()));
1844             }
1845           } else {
1846             Node* phi = target->start_map()->in(j);
1847             if (phi->is_InlineType()) {
1848               // Larval oops cannot be merged with non-larval ones, and since the merge point is
1849               // non-larval, n must be non-larval as well. As a result, we can scalarize n to merge
1850               // into phi
1851               if (!n->is_InlineType()) {
1852                 map()->set_req(j, InlineTypeNode::make_from_oop(this, n, t->inline_klass()));
1853               }
1854             } else {
1855               // The merge is an oop phi, ensure the input is buffered if it is an InlineTypeNode
1856               if (n->is_InlineType()) {
1857                 map()->set_req(j, n->as_InlineType()->buffer(this));
1858               }
1859             }
1860           }
1861         }
1862       }
1863     }
1864   }
1865   old_jvms->bind_map(map());
1866   set_parse_bci(old_bci);
1867 
1868   if (!target->is_merged()) {   // No prior mapping at this bci
1869     if (TraceOptoParse) { tty->print(" with empty state");  }
1870 
1871     // If this path is dead, do not bother capturing it as a merge.
1872     // It is "as if" we had 1 fewer predecessors from the beginning.
1873     if (stopped()) {
1874       if (TraceOptoParse)  tty->print_cr(", but path is dead and doesn't count");
1875       return;
1876     }
1877 
1878     // Make a region if we know there are multiple or unpredictable inputs.
1879     // (Also, if this is a plain fall-through, we might see another region,
1880     // which must not be allowed into this block's map.)
1881     if (pnum > PhiNode::Input         // Known multiple inputs.
1882         || target->is_handler()       // These have unpredictable inputs.
1883         || target->is_loop_head()     // Known multiple inputs
1884         || control()->is_Region()) {  // We must hide this guy.
1885 
1886       int current_bci = bci();
1887       set_parse_bci(target->start()); // Set target bci

1902       record_for_igvn(r);
1903       // zap all inputs to null for debugging (done in Node(uint) constructor)
1904       // for (int j = 1; j < edges+1; j++) { r->init_req(j, nullptr); }
1905       r->init_req(pnum, control());
1906       set_control(r);
1907       target->copy_irreducible_status_to(r, jvms());
1908       set_parse_bci(current_bci); // Restore bci
1909     }
1910 
1911     // Convert the existing Parser mapping into a mapping at this bci.
1912     store_state_to(target);
1913     assert(target->is_merged(), "do not come here twice");
1914 
1915   } else {                      // Prior mapping at this bci
1916     if (TraceOptoParse) {  tty->print(" with previous state"); }
1917 #ifdef ASSERT
1918     if (target->is_SEL_head()) {
1919       target->mark_merged_backedge(block());
1920     }
1921 #endif
1922 
1923     // We must not manufacture more phis if the target is already parsed.
1924     bool nophi = target->is_parsed();
1925 
1926     SafePointNode* newin = map();// Hang on to incoming mapping
1927     Block* save_block = block(); // Hang on to incoming block;
1928     load_state_from(target);    // Get prior mapping
1929 
1930     assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1931     assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1932     assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1933     assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1934 
1935     // Iterate over my current mapping and the old mapping.
1936     // Where different, insert Phi functions.
1937     // Use any existing Phi functions.
1938     assert(control()->is_Region(), "must be merging to a region");
1939     RegionNode* r = control()->as_Region();
1940 
1941     // Compute where to merge into
1942     // Merge incoming control path
1943     r->init_req(pnum, newin->control());
1944 
1945     if (pnum == 1) {            // Last merge for this Region?
1946       if (!block()->flow()->is_irreducible_loop_secondary_entry()) {
1947         Node* result = _gvn.transform(r);
1948         if (r != result && TraceOptoParse) {
1949           tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1950         }
1951       }
1952       record_for_igvn(r);
1953     }
1954 
1955     // Update all the non-control inputs to map:
1956     assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1957     bool check_elide_phi = target->is_SEL_backedge(save_block);
1958     bool last_merge = (pnum == PhiNode::Input);
1959     for (uint j = 1; j < newin->req(); j++) {
1960       Node* m = map()->in(j);   // Current state of target.
1961       Node* n = newin->in(j);   // Incoming change to target state.
1962       Node* phi;
1963       if (m->is_Phi() && m->as_Phi()->region() == r) {
1964         phi = m;
1965       } else if (m->is_InlineType() && m->as_InlineType()->has_phi_inputs(r)) {
1966         phi = m;
1967       } else {
1968         phi = nullptr;
1969       }
1970       if (m != n) {             // Different; must merge
1971         switch (j) {
1972         // Frame pointer and Return Address never changes
1973         case TypeFunc::FramePtr:// Drop m, use the original value
1974         case TypeFunc::ReturnAdr:
1975           break;
1976         case TypeFunc::Memory:  // Merge inputs to the MergeMem node
1977           assert(phi == nullptr, "the merge contains phis, not vice versa");
1978           merge_memory_edges(n->as_MergeMem(), pnum, nophi);
1979           continue;
1980         default:                // All normal stuff
1981           if (phi == nullptr) {
1982             const JVMState* jvms = map()->jvms();
1983             if (EliminateNestedLocks &&
1984                 jvms->is_mon(j) && jvms->is_monitor_box(j)) {
1985               // BoxLock nodes are not commoning when EliminateNestedLocks is on.
1986               // Use old BoxLock node as merged box.
1987               assert(newin->jvms()->is_monitor_box(j), "sanity");
1988               // This assert also tests that nodes are BoxLock.
1989               assert(BoxLockNode::same_slot(n, m), "sanity");

1996                 // Incremental Inlining before EA and Macro nodes elimination.
1997                 //
1998                 // Incremental Inlining is executed after IGVN optimizations
1999                 // during which BoxLock can be marked as Coarsened.
2000                 old_box->set_coarsened(); // Verifies state
2001                 old_box->set_unbalanced();
2002               }
2003               C->gvn_replace_by(n, m);
2004             } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
2005               phi = ensure_phi(j, nophi);
2006             }
2007           }
2008           break;
2009         }
2010       }
2011       // At this point, n might be top if:
2012       //  - there is no phi (because TypeFlow detected a conflict), or
2013       //  - the corresponding control edges is top (a dead incoming path)
2014       // It is a bug if we create a phi which sees a garbage value on a live path.
2015 
2016       // Merging two inline types?
2017       if (phi != nullptr && phi->is_InlineType()) {
2018         // Reload current state because it may have been updated by ensure_phi
2019         assert(phi == map()->in(j), "unexpected value in map");
2020         assert(phi->as_InlineType()->has_phi_inputs(r), "");
2021         InlineTypeNode* vtm = phi->as_InlineType(); // Current inline type
2022         InlineTypeNode* vtn = n->as_InlineType(); // Incoming inline type
2023         assert(vtm == phi, "Inline type should have Phi input");
2024 
2025 #ifdef ASSERT
2026         if (TraceOptoParse) {
2027           tty->print_cr("\nMerging inline types");
2028           tty->print_cr("Current:");
2029           vtm->dump(2);
2030           tty->print_cr("Incoming:");
2031           vtn->dump(2);
2032           tty->cr();
2033         }
2034 #endif
2035         // Do the merge
2036         vtm->merge_with(&_gvn, vtn, pnum, last_merge);
2037         if (last_merge) {
2038           map()->set_req(j, _gvn.transform(vtm));
2039           record_for_igvn(vtm);
2040         }
2041       } else if (phi != nullptr) {
2042         assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
2043         assert(phi->as_Phi()->region() == r, "");
2044         phi->set_req(pnum, n);  // Then add 'n' to the merge
2045         if (last_merge) {
2046           // Last merge for this Phi.
2047           // So far, Phis have had a reasonable type from ciTypeFlow.
2048           // Now _gvn will join that with the meet of current inputs.
2049           // BOTTOM is never permissible here, 'cause pessimistically
2050           // Phis of pointers cannot lose the basic pointer type.
2051           DEBUG_ONLY(const Type* bt1 = phi->bottom_type());
2052           assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
2053           map()->set_req(j, _gvn.transform(phi));
2054           DEBUG_ONLY(const Type* bt2 = phi->bottom_type());
2055           assert(bt2->higher_equal_speculative(bt1), "must be consistent with type-flow");
2056           record_for_igvn(phi);
2057         }
2058       }
2059     } // End of for all values to be merged
2060 
2061     if (last_merge && !r->in(0)) {         // The occasional useless Region

2062       assert(control() == r, "");
2063       set_control(r->nonnull_req());
2064     }
2065 
2066     map()->merge_replaced_nodes_with(newin);
2067 
2068     // newin has been subsumed into the lazy merge, and is now dead.
2069     set_block(save_block);
2070 
2071     stop();                     // done with this guy, for now
2072   }
2073 
2074   if (TraceOptoParse) {
2075     tty->print_cr(" on path %d", pnum);
2076   }
2077 
2078   // Done with this parser state.
2079   assert(stopped(), "");
2080 }
2081 

2193 
2194   // Add new path to the region.
2195   uint pnum = r->req();
2196   r->add_req(nullptr);
2197 
2198   for (uint i = 1; i < map->req(); i++) {
2199     Node* n = map->in(i);
2200     if (i == TypeFunc::Memory) {
2201       // Ensure a phi on all currently known memories.
2202       for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
2203         Node* phi = mms.memory();
2204         if (phi->is_Phi() && phi->as_Phi()->region() == r) {
2205           assert(phi->req() == pnum, "must be same size as region");
2206           phi->add_req(nullptr);
2207         }
2208       }
2209     } else {
2210       if (n->is_Phi() && n->as_Phi()->region() == r) {
2211         assert(n->req() == pnum, "must be same size as region");
2212         n->add_req(nullptr);
2213       } else if (n->is_InlineType() && n->as_InlineType()->has_phi_inputs(r)) {
2214         n->as_InlineType()->add_new_path(r);
2215       }
2216     }
2217   }
2218 
2219   return pnum;
2220 }
2221 
2222 //------------------------------ensure_phi-------------------------------------
2223 // Turn the idx'th entry of the current map into a Phi
2224 Node* Parse::ensure_phi(int idx, bool nocreate) {
2225   SafePointNode* map = this->map();
2226   Node* region = map->control();
2227   assert(region->is_Region(), "");
2228 
2229   Node* o = map->in(idx);
2230   assert(o != nullptr, "");
2231 
2232   if (o == top())  return nullptr; // TOP always merges into TOP
2233 
2234   if (o->is_Phi() && o->as_Phi()->region() == region) {
2235     return o->as_Phi();
2236   }
2237   InlineTypeNode* vt = o->isa_InlineType();
2238   if (vt != nullptr && vt->has_phi_inputs(region)) {
2239     return vt;
2240   }
2241 
2242   // Now use a Phi here for merging
2243   assert(!nocreate, "Cannot build a phi for a block already parsed.");
2244   const JVMState* jvms = map->jvms();
2245   const Type* t = nullptr;
2246   if (jvms->is_loc(idx)) {
2247     t = block()->local_type_at(idx - jvms->locoff());
2248   } else if (jvms->is_stk(idx)) {
2249     t = block()->stack_type_at(idx - jvms->stkoff());
2250   } else if (jvms->is_mon(idx)) {
2251     assert(!jvms->is_monitor_box(idx), "no phis for boxes");
2252     t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
2253   } else if ((uint)idx < TypeFunc::Parms) {
2254     t = o->bottom_type();  // Type::RETURN_ADDRESS or such-like.
2255   } else {
2256     assert(false, "no type information for this phi");
2257   }
2258 
2259   // If the type falls to bottom, then this must be a local that
2260   // is already dead or is mixing ints and oops or some such.
2261   // Forcing it to top makes it go dead.
2262   if (t == Type::BOTTOM) {
2263     map->set_req(idx, top());
2264     return nullptr;
2265   }
2266 
2267   // Do not create phis for top either.
2268   // A top on a non-null control flow must be an unused even after the.phi.
2269   if (t == Type::TOP || t == Type::HALF) {
2270     map->set_req(idx, top());
2271     return nullptr;
2272   }
2273 
2274   if (vt != nullptr && t->is_inlinetypeptr()) {
2275     // Inline types are merged by merging their field values.
2276     // Create a cloned InlineTypeNode with phi inputs that
2277     // represents the merged inline type and update the map.
2278     vt = vt->clone_with_phis(&_gvn, region);
2279     map->set_req(idx, vt);
2280     return vt;
2281   } else {
2282     PhiNode* phi = PhiNode::make(region, o, t);
2283     gvn().set_type(phi, t);
2284     if (C->do_escape_analysis()) record_for_igvn(phi);
2285     map->set_req(idx, phi);
2286     return phi;
2287   }
2288 }
2289 
2290 //--------------------------ensure_memory_phi----------------------------------
2291 // Turn the idx'th slice of the current memory into a Phi
2292 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
2293   MergeMemNode* mem = merged_memory();
2294   Node* region = control();
2295   assert(region->is_Region(), "");
2296 
2297   Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
2298   assert(o != nullptr && o != top(), "");
2299 
2300   PhiNode* phi;
2301   if (o->is_Phi() && o->as_Phi()->region() == region) {
2302     phi = o->as_Phi();
2303     if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
2304       // clone the shared base memory phi to make a new memory split
2305       assert(!nocreate, "Cannot build a phi for a block already parsed.");
2306       const Type* t = phi->bottom_type();
2307       const TypePtr* adr_type = C->get_adr_type(idx);

2397 // Add check to deoptimize once holder klass is fully initialized.
2398 void Parse::clinit_deopt() {
2399   assert(C->has_method(), "only for normal compilations");
2400   assert(depth() == 1, "only for main compiled method");
2401   assert(is_normal_parse(), "no barrier needed on osr entry");
2402   assert(!method()->holder()->is_not_initialized(), "initialization should have been started");
2403 
2404   set_parse_bci(0);
2405 
2406   Node* holder = makecon(TypeKlassPtr::make(method()->holder(), Type::trust_interfaces));
2407   guard_klass_being_initialized(holder);
2408 }
2409 
2410 //------------------------------return_current---------------------------------
2411 // Append current _map to _exit_return
2412 void Parse::return_current(Node* value) {
2413   if (method()->intrinsic_id() == vmIntrinsics::_Object_init) {
2414     call_register_finalizer();
2415   }
2416 
2417   // frame pointer is always same, already captured
2418   if (value != nullptr) {
2419     Node* phi = _exits.argument(0);
2420     const Type* return_type = phi->bottom_type();
2421     const TypeInstPtr* tr = return_type->isa_instptr();
2422     if ((tf()->returns_inline_type_as_fields() || (_caller->has_method() && !Compile::current()->inlining_incrementally())) &&
2423         return_type->is_inlinetypeptr()) {
2424       // Inline type is returned as fields, make sure it is scalarized
2425       if (!value->is_InlineType()) {
2426         value = InlineTypeNode::make_from_oop(this, value, return_type->inline_klass());
2427       }
2428       if (!_caller->has_method() || Compile::current()->inlining_incrementally()) {
2429         // Returning from root or an incrementally inlined method. Make sure all non-flat
2430         // fields are buffered and re-execute if allocation triggers deoptimization.
2431         PreserveReexecuteState preexecs(this);
2432         assert(tf()->returns_inline_type_as_fields(), "must be returned as fields");
2433         jvms()->set_should_reexecute(true);
2434         inc_sp(1);
2435         value = value->as_InlineType()->allocate_fields(this);
2436       }
2437     } else if (value->is_InlineType()) {
2438       // Inline type is returned as oop, make sure it is buffered and re-execute
2439       // if allocation triggers deoptimization.
2440       PreserveReexecuteState preexecs(this);
2441       jvms()->set_should_reexecute(true);
2442       inc_sp(1);
2443       value = value->as_InlineType()->buffer(this);
2444     }
2445     // ...else
2446     // If returning oops to an interface-return, there is a silent free
2447     // cast from oop to interface allowed by the Verifier. Make it explicit here.
2448     phi->add_req(value);
2449   }
2450 
2451   // Do not set_parse_bci, so that return goo is credited to the return insn.
2452   set_bci(InvocationEntryBci);
2453   if (method()->is_synchronized()) {
2454     shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
2455   }
2456   if (C->env()->dtrace_method_probes()) {
2457     make_dtrace_method_exit(method());
2458   }
2459 
2460   SafePointNode* exit_return = _exits.map();
2461   exit_return->in( TypeFunc::Control  )->add_req( control() );
2462   exit_return->in( TypeFunc::I_O      )->add_req( i_o    () );
2463   Node *mem = exit_return->in( TypeFunc::Memory   );
2464   for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
2465     if (mms.is_empty()) {
2466       // get a copy of the base memory, and patch just this one input
2467       const TypePtr* adr_type = mms.adr_type(C);
2468       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
2469       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
2470       gvn().set_type_bottom(phi);
2471       phi->del_req(phi->req()-1);  // prepare to re-patch
2472       mms.set_memory(phi);
2473     }
2474     mms.memory()->add_req(mms.memory2());
2475   }
2476 









2477   if (_first_return) {
2478     _exits.map()->transfer_replaced_nodes_from(map(), _new_idx);
2479     _first_return = false;
2480   } else {
2481     _exits.map()->merge_replaced_nodes_with(map());
2482   }
2483 
2484   stop_and_kill_map();          // This CFG path dies here
2485 }
2486 
2487 
2488 //------------------------------add_safepoint----------------------------------
2489 void Parse::add_safepoint() {
2490   uint parms = TypeFunc::Parms+1;
2491 
2492   // Clear out dead values from the debug info.
2493   kill_dead_locals();
2494 
2495   // Clone the JVM State
2496   SafePointNode *sfpnt = new SafePointNode(parms, nullptr);
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