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src/hotspot/share/opto/parse1.cpp

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   1 /*
   2  * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 


  25 #include "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;
  53 uint methods_seen              = 0;
  54 uint blocks_parsed             = 0;
  55 uint blocks_seen               = 0;
  56 
  57 uint explicit_null_checks_inserted = 0;
  58 uint explicit_null_checks_elided   = 0;
  59 uint all_null_checks_found         = 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 

1236 
1237   // If the method is synchronized, we need to construct a lock node, attach
1238   // it to the Start node, and pin it there.
1239   if (method()->is_synchronized()) {
1240     // Insert a FastLockNode right after the Start which takes as arguments
1241     // the current thread pointer, the "this" pointer & the address of the
1242     // stack slot pair used for the lock.  The "this" pointer is a projection
1243     // off the start node, but the locking spot has to be constructed by
1244     // creating a ConLNode of 0, and boxing it with a BoxLockNode.  The BoxLockNode
1245     // becomes the second argument to the FastLockNode call.  The
1246     // FastLockNode becomes the new control parent to pin it to the start.
1247 
1248     // Setup Object Pointer
1249     Node *lock_obj = nullptr;
1250     if (method()->is_static()) {
1251       ciInstance* mirror = _method->holder()->java_mirror();
1252       const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1253       lock_obj = makecon(t_lock);
1254     } else {                  // Else pass the "this" pointer,
1255       lock_obj = local(0);    // which is Parm0 from StartNode

1256     }
1257     // Clear out dead values from the debug info.
1258     kill_dead_locals();
1259     // Build the FastLockNode
1260     _synch_lock = shared_lock(lock_obj);
1261     // Check for bailout in shared_lock
1262     if (failing()) { return; }
1263   }
1264 
1265   // Feed profiling data for parameters to the type system so it can
1266   // propagate it as speculative types
1267   record_profiled_parameters_for_speculation();
1268 }
1269 
1270 //------------------------------init_blocks------------------------------------
1271 // Initialize our parser map to contain the types/monitors at method entry.
1272 void Parse::init_blocks() {
1273   // Create the blocks.
1274   _block_count = flow()->block_count();
1275   _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);

1671 //--------------------handle_missing_successor---------------------------------
1672 void Parse::handle_missing_successor(int target_bci) {
1673 #ifndef PRODUCT
1674   Block* b = block();
1675   int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
1676   tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
1677 #endif
1678   ShouldNotReachHere();
1679 }
1680 
1681 //--------------------------merge_common---------------------------------------
1682 void Parse::merge_common(Parse::Block* target, int pnum) {
1683   if (TraceOptoParse) {
1684     tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
1685   }
1686 
1687   // Zap extra stack slots to top
1688   assert(sp() == target->start_sp(), "");
1689   clean_stack(sp());
1690 


































































1691   if (!target->is_merged()) {   // No prior mapping at this bci
1692     if (TraceOptoParse) { tty->print(" with empty state");  }
1693 
1694     // If this path is dead, do not bother capturing it as a merge.
1695     // It is "as if" we had 1 fewer predecessors from the beginning.
1696     if (stopped()) {
1697       if (TraceOptoParse)  tty->print_cr(", but path is dead and doesn't count");
1698       return;
1699     }
1700 
1701     // Make a region if we know there are multiple or unpredictable inputs.
1702     // (Also, if this is a plain fall-through, we might see another region,
1703     // which must not be allowed into this block's map.)
1704     if (pnum > PhiNode::Input         // Known multiple inputs.
1705         || target->is_handler()       // These have unpredictable inputs.
1706         || target->is_loop_head()     // Known multiple inputs
1707         || control()->is_Region()) {  // We must hide this guy.
1708 
1709       int current_bci = bci();
1710       set_parse_bci(target->start()); // Set target bci

1725       record_for_igvn(r);
1726       // zap all inputs to null for debugging (done in Node(uint) constructor)
1727       // for (int j = 1; j < edges+1; j++) { r->init_req(j, nullptr); }
1728       r->init_req(pnum, control());
1729       set_control(r);
1730       target->copy_irreducible_status_to(r, jvms());
1731       set_parse_bci(current_bci); // Restore bci
1732     }
1733 
1734     // Convert the existing Parser mapping into a mapping at this bci.
1735     store_state_to(target);
1736     assert(target->is_merged(), "do not come here twice");
1737 
1738   } else {                      // Prior mapping at this bci
1739     if (TraceOptoParse) {  tty->print(" with previous state"); }
1740 #ifdef ASSERT
1741     if (target->is_SEL_head()) {
1742       target->mark_merged_backedge(block());
1743     }
1744 #endif

1745     // We must not manufacture more phis if the target is already parsed.
1746     bool nophi = target->is_parsed();
1747 
1748     SafePointNode* newin = map();// Hang on to incoming mapping
1749     Block* save_block = block(); // Hang on to incoming block;
1750     load_state_from(target);    // Get prior mapping
1751 
1752     assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1753     assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1754     assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1755     assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1756 
1757     // Iterate over my current mapping and the old mapping.
1758     // Where different, insert Phi functions.
1759     // Use any existing Phi functions.
1760     assert(control()->is_Region(), "must be merging to a region");
1761     RegionNode* r = control()->as_Region();
1762 
1763     // Compute where to merge into
1764     // Merge incoming control path
1765     r->init_req(pnum, newin->control());
1766 
1767     if (pnum == 1) {            // Last merge for this Region?
1768       if (!block()->flow()->is_irreducible_loop_secondary_entry()) {
1769         Node* result = _gvn.transform(r);
1770         if (r != result && TraceOptoParse) {
1771           tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1772         }
1773       }
1774       record_for_igvn(r);
1775     }
1776 
1777     // Update all the non-control inputs to map:
1778     assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1779     bool check_elide_phi = target->is_SEL_backedge(save_block);

1780     for (uint j = 1; j < newin->req(); j++) {
1781       Node* m = map()->in(j);   // Current state of target.
1782       Node* n = newin->in(j);   // Incoming change to target state.
1783       PhiNode* phi;
1784       if (m->is_Phi() && m->as_Phi()->region() == r)
1785         phi = m->as_Phi();
1786       else


1787         phi = nullptr;

1788       if (m != n) {             // Different; must merge
1789         switch (j) {
1790         // Frame pointer and Return Address never changes
1791         case TypeFunc::FramePtr:// Drop m, use the original value
1792         case TypeFunc::ReturnAdr:
1793           break;
1794         case TypeFunc::Memory:  // Merge inputs to the MergeMem node
1795           assert(phi == nullptr, "the merge contains phis, not vice versa");
1796           merge_memory_edges(n->as_MergeMem(), pnum, nophi);
1797           continue;
1798         default:                // All normal stuff
1799           if (phi == nullptr) {
1800             const JVMState* jvms = map()->jvms();
1801             if (EliminateNestedLocks &&
1802                 jvms->is_mon(j) && jvms->is_monitor_box(j)) {
1803               // BoxLock nodes are not commoning when EliminateNestedLocks is on.
1804               // Use old BoxLock node as merged box.
1805               assert(newin->jvms()->is_monitor_box(j), "sanity");
1806               // This assert also tests that nodes are BoxLock.
1807               assert(BoxLockNode::same_slot(n, m), "sanity");

1814                 // Incremental Inlining before EA and Macro nodes elimination.
1815                 //
1816                 // Incremental Inlining is executed after IGVN optimizations
1817                 // during which BoxLock can be marked as Coarsened.
1818                 old_box->set_coarsened(); // Verifies state
1819                 old_box->set_unbalanced();
1820               }
1821               C->gvn_replace_by(n, m);
1822             } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
1823               phi = ensure_phi(j, nophi);
1824             }
1825           }
1826           break;
1827         }
1828       }
1829       // At this point, n might be top if:
1830       //  - there is no phi (because TypeFlow detected a conflict), or
1831       //  - the corresponding control edges is top (a dead incoming path)
1832       // It is a bug if we create a phi which sees a garbage value on a live path.
1833 
1834       if (phi != nullptr) {

























1835         assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
1836         assert(phi->region() == r, "");
1837         phi->set_req(pnum, n);  // Then add 'n' to the merge
1838         if (pnum == PhiNode::Input) {
1839           // Last merge for this Phi.
1840           // So far, Phis have had a reasonable type from ciTypeFlow.
1841           // Now _gvn will join that with the meet of current inputs.
1842           // BOTTOM is never permissible here, 'cause pessimistically
1843           // Phis of pointers cannot lose the basic pointer type.
1844           DEBUG_ONLY(const Type* bt1 = phi->bottom_type());
1845           assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
1846           map()->set_req(j, _gvn.transform(phi));
1847           DEBUG_ONLY(const Type* bt2 = phi->bottom_type());
1848           assert(bt2->higher_equal_speculative(bt1), "must be consistent with type-flow");
1849           record_for_igvn(phi);
1850         }
1851       }
1852     } // End of for all values to be merged
1853 
1854     if (pnum == PhiNode::Input &&
1855         !r->in(0)) {         // The occasional useless Region
1856       assert(control() == r, "");
1857       set_control(r->nonnull_req());
1858     }
1859 
1860     map()->merge_replaced_nodes_with(newin);
1861 
1862     // newin has been subsumed into the lazy merge, and is now dead.
1863     set_block(save_block);
1864 
1865     stop();                     // done with this guy, for now
1866   }
1867 
1868   if (TraceOptoParse) {
1869     tty->print_cr(" on path %d", pnum);
1870   }
1871 
1872   // Done with this parser state.
1873   assert(stopped(), "");
1874 }
1875 

1987 
1988   // Add new path to the region.
1989   uint pnum = r->req();
1990   r->add_req(nullptr);
1991 
1992   for (uint i = 1; i < map->req(); i++) {
1993     Node* n = map->in(i);
1994     if (i == TypeFunc::Memory) {
1995       // Ensure a phi on all currently known memories.
1996       for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
1997         Node* phi = mms.memory();
1998         if (phi->is_Phi() && phi->as_Phi()->region() == r) {
1999           assert(phi->req() == pnum, "must be same size as region");
2000           phi->add_req(nullptr);
2001         }
2002       }
2003     } else {
2004       if (n->is_Phi() && n->as_Phi()->region() == r) {
2005         assert(n->req() == pnum, "must be same size as region");
2006         n->add_req(nullptr);


2007       }
2008     }
2009   }
2010 
2011   return pnum;
2012 }
2013 
2014 //------------------------------ensure_phi-------------------------------------
2015 // Turn the idx'th entry of the current map into a Phi
2016 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
2017   SafePointNode* map = this->map();
2018   Node* region = map->control();
2019   assert(region->is_Region(), "");
2020 
2021   Node* o = map->in(idx);
2022   assert(o != nullptr, "");
2023 
2024   if (o == top())  return nullptr; // TOP always merges into TOP
2025 
2026   if (o->is_Phi() && o->as_Phi()->region() == region) {
2027     return o->as_Phi();
2028   }




2029 
2030   // Now use a Phi here for merging
2031   assert(!nocreate, "Cannot build a phi for a block already parsed.");
2032   const JVMState* jvms = map->jvms();
2033   const Type* t = nullptr;
2034   if (jvms->is_loc(idx)) {
2035     t = block()->local_type_at(idx - jvms->locoff());
2036   } else if (jvms->is_stk(idx)) {
2037     t = block()->stack_type_at(idx - jvms->stkoff());
2038   } else if (jvms->is_mon(idx)) {
2039     assert(!jvms->is_monitor_box(idx), "no phis for boxes");
2040     t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
2041   } else if ((uint)idx < TypeFunc::Parms) {
2042     t = o->bottom_type();  // Type::RETURN_ADDRESS or such-like.
2043   } else {
2044     assert(false, "no type information for this phi");
2045   }
2046 
2047   // If the type falls to bottom, then this must be a local that
2048   // is mixing ints and oops or some such.  Forcing it to top
2049   // makes it go dead.
2050   if (t == Type::BOTTOM) {
2051     map->set_req(idx, top());
2052     return nullptr;
2053   }
2054 
2055   // Do not create phis for top either.
2056   // A top on a non-null control flow must be an unused even after the.phi.
2057   if (t == Type::TOP || t == Type::HALF) {
2058     map->set_req(idx, top());
2059     return nullptr;
2060   }
2061 
2062   PhiNode* phi = PhiNode::make(region, o, t);
2063   gvn().set_type(phi, t);
2064   if (C->do_escape_analysis()) record_for_igvn(phi);
2065   map->set_req(idx, phi);
2066   return phi;









2067 }
2068 
2069 //--------------------------ensure_memory_phi----------------------------------
2070 // Turn the idx'th slice of the current memory into a Phi
2071 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
2072   MergeMemNode* mem = merged_memory();
2073   Node* region = control();
2074   assert(region->is_Region(), "");
2075 
2076   Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
2077   assert(o != nullptr && o != top(), "");
2078 
2079   PhiNode* phi;
2080   if (o->is_Phi() && o->as_Phi()->region() == region) {
2081     phi = o->as_Phi();
2082     if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
2083       // clone the shared base memory phi to make a new memory split
2084       assert(!nocreate, "Cannot build a phi for a block already parsed.");
2085       const Type* t = phi->bottom_type();
2086       const TypePtr* adr_type = C->get_adr_type(idx);

2176 // Add check to deoptimize once holder klass is fully initialized.
2177 void Parse::clinit_deopt() {
2178   assert(C->has_method(), "only for normal compilations");
2179   assert(depth() == 1, "only for main compiled method");
2180   assert(is_normal_parse(), "no barrier needed on osr entry");
2181   assert(!method()->holder()->is_not_initialized(), "initialization should have been started");
2182 
2183   set_parse_bci(0);
2184 
2185   Node* holder = makecon(TypeKlassPtr::make(method()->holder(), Type::trust_interfaces));
2186   guard_klass_being_initialized(holder);
2187 }
2188 
2189 //------------------------------return_current---------------------------------
2190 // Append current _map to _exit_return
2191 void Parse::return_current(Node* value) {
2192   if (method()->intrinsic_id() == vmIntrinsics::_Object_init) {
2193     call_register_finalizer();
2194   }
2195 


































2196   // Do not set_parse_bci, so that return goo is credited to the return insn.
2197   set_bci(InvocationEntryBci);
2198   if (method()->is_synchronized()) {
2199     shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
2200   }
2201   if (C->env()->dtrace_method_probes()) {
2202     make_dtrace_method_exit(method());
2203   }

2204   SafePointNode* exit_return = _exits.map();
2205   exit_return->in( TypeFunc::Control  )->add_req( control() );
2206   exit_return->in( TypeFunc::I_O      )->add_req( i_o    () );
2207   Node *mem = exit_return->in( TypeFunc::Memory   );
2208   for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
2209     if (mms.is_empty()) {
2210       // get a copy of the base memory, and patch just this one input
2211       const TypePtr* adr_type = mms.adr_type(C);
2212       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
2213       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
2214       gvn().set_type_bottom(phi);
2215       phi->del_req(phi->req()-1);  // prepare to re-patch
2216       mms.set_memory(phi);
2217     }
2218     mms.memory()->add_req(mms.memory2());
2219   }
2220 
2221   // frame pointer is always same, already captured
2222   if (value != nullptr) {
2223     // If returning oops to an interface-return, there is a silent free
2224     // cast from oop to interface allowed by the Verifier.  Make it explicit
2225     // here.
2226     Node* phi = _exits.argument(0);
2227     phi->add_req(value);
2228   }
2229 
2230   if (_first_return) {
2231     _exits.map()->transfer_replaced_nodes_from(map(), _new_idx);
2232     _first_return = false;
2233   } else {
2234     _exits.map()->merge_replaced_nodes_with(map());
2235   }
2236 
2237   stop_and_kill_map();          // This CFG path dies here
2238 }
2239 
2240 
2241 //------------------------------add_safepoint----------------------------------
2242 void Parse::add_safepoint() {
2243   uint parms = TypeFunc::Parms+1;
2244 
2245   // Clear out dead values from the debug info.
2246   kill_dead_locals();
2247 
2248   // Clone the JVM State
2249   SafePointNode *sfpnt = new SafePointNode(parms, nullptr);

   1 /*
   2  * Copyright (c) 1997, 2026, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "ci/ciObjArrayKlass.hpp"
  26 #include "ci/ciSignature.hpp"
  27 #include "compiler/compileLog.hpp"
  28 #include "interpreter/linkResolver.hpp"
  29 #include "memory/resourceArea.hpp"
  30 #include "oops/method.hpp"
  31 #include "opto/addnode.hpp"
  32 #include "opto/c2compiler.hpp"
  33 #include "opto/castnode.hpp"
  34 #include "opto/convertnode.hpp"
  35 #include "opto/idealGraphPrinter.hpp"
  36 #include "opto/inlinetypenode.hpp"
  37 #include "opto/locknode.hpp"
  38 #include "opto/memnode.hpp"
  39 #include "opto/opaquenode.hpp"
  40 #include "opto/parse.hpp"
  41 #include "opto/rootnode.hpp"
  42 #include "opto/runtime.hpp"
  43 #include "opto/type.hpp"
  44 #include "runtime/arguments.hpp"
  45 #include "runtime/handles.inline.hpp"
  46 #include "runtime/safepointMechanism.hpp"
  47 #include "runtime/sharedRuntime.hpp"
  48 #include "utilities/bitMap.inline.hpp"
  49 #include "utilities/copy.hpp"
  50 
  51 // Static array so we can figure out which bytecodes stop us from compiling
  52 // the most. Some of the non-static variables are needed in bytecodeInfo.cpp
  53 // and eventually should be encapsulated in a proper class (gri 8/18/98).
  54 
  55 #ifndef PRODUCT
  56 uint nodes_created             = 0;
  57 uint methods_parsed            = 0;
  58 uint methods_seen              = 0;
  59 uint blocks_parsed             = 0;
  60 uint blocks_seen               = 0;
  61 
  62 uint explicit_null_checks_inserted = 0;
  63 uint explicit_null_checks_elided   = 0;
  64 uint all_null_checks_found         = 0;

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

 160   const TypeOopPtr* tp = type->isa_oopptr();
 161 
 162   // TypeFlow may assert null-ness if a type appears unloaded.
 163   if (type == TypePtr::NULL_PTR ||
 164       (tp != nullptr && !tp->is_loaded())) {
 165     // Value must be null, not a real oop.
 166     Node* chk = _gvn.transform( new CmpPNode(l, null()) );
 167     Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
 168     IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
 169     set_control(_gvn.transform( new IfTrueNode(iff) ));
 170     Node* bad_type = _gvn.transform( new IfFalseNode(iff) );
 171     bad_type_exit->control()->add_req(bad_type);
 172     l = null();
 173   }
 174 
 175   // Typeflow can also cut off paths from the CFG, based on
 176   // types which appear unloaded, or call sites which appear unlinked.
 177   // When paths are cut off, values at later merge points can rise
 178   // toward more specific classes.  Make sure these specific classes
 179   // are still in effect.
 180   if (tp != nullptr && !tp->is_same_java_type_as(TypeInstPtr::BOTTOM)) {
 181     // TypeFlow asserted a specific object type.  Value must have that type.
 182     Node* bad_type_ctrl = nullptr;
 183     if (tp->is_inlinetypeptr() && !tp->maybe_null()) {
 184       // Check inline types for null here to prevent checkcast from adding an
 185       // exception state before the bytecode entry (use 'bad_type_ctrl' instead).
 186       l = null_check_oop(l, &bad_type_ctrl);
 187       bad_type_exit->control()->add_req(bad_type_ctrl);
 188     }
 189 
 190     l = gen_checkcast(l, makecon(klass_type), &bad_type_ctrl, false, is_early_larval);
 191     bad_type_exit->control()->add_req(bad_type_ctrl);
 192   }
 193 
 194   assert(_gvn.type(l)->higher_equal(type), "must constrain OSR typestate");
 195   return l;
 196 }
 197 
 198 // Helper routine which sets up elements of the initial parser map when
 199 // performing a parse for on stack replacement.  Add values into map.
 200 // The only parameter contains the address of a interpreter arguments.
 201 void Parse::load_interpreter_state(Node* osr_buf) {
 202   int index;
 203   int max_locals = jvms()->loc_size();
 204   int max_stack  = jvms()->stk_size();
 205 

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

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

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

 310         if (C->log() != nullptr) {
 311           C->log()->elem("OSR_mismatch local_index='%d'",index);
 312         }
 313         set_local(index, null());
 314         // and ignore it for the loads
 315         continue;
 316       }
 317     }
 318 
 319     // Filter out TOP, HALF, and BOTTOM.  (Cf. ensure_phi.)
 320     if (type == Type::TOP || type == Type::HALF) {
 321       continue;
 322     }
 323     // If the type falls to bottom, then this must be a local that
 324     // is mixing ints and oops or some such.  Forcing it to top
 325     // makes it go dead.
 326     if (type == Type::BOTTOM) {
 327       continue;
 328     }
 329     // Construct code to access the appropriate local.
 330     Node* value = fetch_interpreter_state(index, type, locals_addr, osr_buf);






 331     set_local(index, value);
 332   }
 333 
 334   // Extract the needed stack entries from the interpreter frame.
 335   for (index = 0; index < sp(); index++) {
 336     const Type *type = osr_block->stack_type_at(index);
 337     if (type != Type::TOP) {
 338       // Currently the compiler bails out when attempting to on stack replace
 339       // at a bci with a non-empty stack.  We should not reach here.
 340       ShouldNotReachHere();
 341     }
 342   }
 343 
 344   // End the OSR migration
 345   make_runtime_call(RC_LEAF, OptoRuntime::osr_end_Type(),
 346                     CAST_FROM_FN_PTR(address, SharedRuntime::OSR_migration_end),
 347                     "OSR_migration_end", TypeRawPtr::BOTTOM,
 348                     osr_buf);
 349 
 350   // Now that the interpreter state is loaded, make sure it will match

 361     if (type->isa_oopptr() != nullptr) {
 362       if (!live_oops.at(index)) {
 363         // skip type check for dead oops
 364         continue;
 365       }
 366     }
 367     if (osr_block->flow()->local_type_at(index)->is_return_address()) {
 368       // In our current system it's illegal for jsr addresses to be
 369       // live into an OSR entry point because the compiler performs
 370       // inlining of jsrs.  ciTypeFlow has a bailout that detect this
 371       // case and aborts the compile if addresses are live into an OSR
 372       // entry point.  Because of that we can assume that any address
 373       // locals at the OSR entry point are dead.  Method liveness
 374       // isn't precise enough to figure out that they are dead in all
 375       // cases so simply skip checking address locals all
 376       // together. Any type check is guaranteed to fail since the
 377       // interpreter type is the result of a load which might have any
 378       // value and the expected type is a constant.
 379       continue;
 380     }
 381     const TypeKlassPtr* klass_type = nullptr;
 382     if (type->isa_oopptr()) {
 383       klass_type = TypeKlassPtr::make(osr_block->flow()->local_type_at(index)->unwrap()->as_klass(), Type::ignore_interfaces);
 384       klass_type = klass_type->try_improve();
 385     }
 386     bool is_early_larval = osr_block->flow()->local_type_at(index)->is_early_larval();
 387     set_local(index, check_interpreter_type(l, type, klass_type, bad_type_exit, is_early_larval));
 388   }
 389 
 390   for (index = 0; index < sp(); index++) {
 391     if (stopped())  break;
 392     Node* l = stack(index);
 393     if (l->is_top())  continue;  // nothing here
 394     const Type* type = osr_block->stack_type_at(index);
 395     const TypeKlassPtr* klass_type = nullptr;
 396     if (type->isa_oopptr()) {
 397       klass_type = TypeKlassPtr::make(osr_block->flow()->stack_type_at(index)->unwrap()->as_klass(), Type::ignore_interfaces);
 398       klass_type = klass_type->try_improve();
 399     }
 400     bool is_early_larval = osr_block->flow()->stack_type_at(index)->is_early_larval();
 401     set_stack(index, check_interpreter_type(l, type, klass_type, bad_type_exit, is_early_larval));
 402   }
 403 
 404   if (bad_type_exit->control()->req() > 1) {
 405     // Build an uncommon trap here, if any inputs can be unexpected.
 406     bad_type_exit->set_control(_gvn.transform( bad_type_exit->control() ));
 407     record_for_igvn(bad_type_exit->control());
 408     SafePointNode* types_are_good = map();
 409     set_map(bad_type_exit);
 410     // The unexpected type happens because a new edge is active
 411     // in the CFG, which typeflow had previously ignored.
 412     // E.g., Object x = coldAtFirst() && notReached()? "str": new Integer(123).
 413     // This x will be typed as Integer if notReached is not yet linked.
 414     // It could also happen due to a problem in ciTypeFlow analysis.
 415     uncommon_trap(Deoptimization::Reason_constraint,
 416                   Deoptimization::Action_reinterpret);
 417     set_map(types_are_good);
 418   }
 419 }
 420 
 421 //------------------------------Parse------------------------------------------

 522   // either breakpoint setting or hotswapping of methods may
 523   // cause deoptimization.
 524   if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
 525     C->dependencies()->assert_evol_method(method());
 526   }
 527 
 528   NOT_PRODUCT(methods_seen++);
 529 
 530   // Do some special top-level things.
 531   if (depth() == 1 && C->is_osr_compilation()) {
 532     _tf = C->tf();     // the OSR entry type is different
 533     _entry_bci = C->entry_bci();
 534     _flow = method()->get_osr_flow_analysis(osr_bci());
 535   } else {
 536     _tf = TypeFunc::make(method());
 537     _entry_bci = InvocationEntryBci;
 538     _flow = method()->get_flow_analysis();
 539   }
 540 
 541   if (_flow->failing()) {
 542     // TODO Adding a trap due to an unloaded return type in ciTypeFlow::StateVector::do_invoke
 543     // can lead to this. Re-enable once 8284443 is fixed.
 544     //assert(false, "type flow analysis failed during parsing");
 545     C->record_method_not_compilable(_flow->failure_reason());
 546 #ifndef PRODUCT
 547       if (PrintOpto && (Verbose || WizardMode)) {
 548         if (is_osr_parse()) {
 549           tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
 550         } else {
 551           tty->print_cr("type flow bailout: %s", _flow->failure_reason());
 552         }
 553         if (Verbose) {
 554           method()->print();
 555           method()->print_codes();
 556           _flow->print();
 557         }
 558       }
 559 #endif
 560   }
 561 
 562 #ifdef ASSERT
 563   if (depth() == 1) {
 564     assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");

 615     load_interpreter_state(osr_buf);
 616   } else {
 617     set_map(entry_map);
 618     do_method_entry();
 619   }
 620 
 621   if (depth() == 1 && !failing()) {
 622     if (C->clinit_barrier_on_entry()) {
 623       // Add check to deoptimize the nmethod once the holder class is fully initialized
 624       clinit_deopt();
 625     }
 626   }
 627 
 628   // Check for bailouts during method entry.
 629   if (failing()) {
 630     if (log)  log->done("parse");
 631     C->set_default_node_notes(caller_nn);
 632     return;
 633   }
 634 
 635   // Handle inline type arguments
 636   int arg_size = method()->arg_size();
 637   for (int i = 0; i < arg_size; i++) {
 638     Node* parm = local(i);
 639     const Type* t = _gvn.type(parm);
 640     if (t->is_inlinetypeptr()) {
 641       // If the parameter is a value object, try to scalarize it if we know that it is unrestricted (not early larval)
 642       // Parameters are non-larval except the receiver of a constructor, which must be an early larval object.
 643       if (!(method()->is_object_constructor() && i == 0)) {
 644         // Create InlineTypeNode from the oop and replace the parameter
 645         Node* vt = InlineTypeNode::make_from_oop(this, parm, t->inline_klass());
 646         replace_in_map(parm, vt);
 647       }
 648     } else if (UseTypeSpeculation && (i == (arg_size - 1)) && !is_osr_parse() && depth() == 1 && method()->has_vararg() && t->isa_aryptr()) {
 649       // Speculate on varargs Object array being the default array refined type. The assumption is
 650       // that a vararg method test(Object... o) is often called as test(o1, o2, o3). javac will
 651       // translate the call so that the caller will create a new default array of Object, put o1,
 652       // o2, o3 into the newly created array, then invoke the method test. This only makes sense if
 653       // the method we are parsing is the top-level method of the compilation unit. Otherwise, if
 654       // it is truly called according to our assumption, we must know the exact type of the
 655       // argument because the allocation happens inside the compilation unit.
 656       const TypePtr* spec_type = (t->speculative() != nullptr) ? t->speculative() : t->remove_speculative()->is_aryptr();
 657       ciSignature* method_signature = method()->signature();
 658       ciType* parm_citype = method_signature->type_at(method_signature->count() - 1);
 659       if (!parm_citype->is_obj_array_klass()) {
 660         continue;
 661       }
 662 
 663       ciObjArrayKlass* spec_citype = ciObjArrayKlass::make(parm_citype->as_obj_array_klass()->element_klass(), true);
 664       const Type* improved_spec_type = TypeKlassPtr::make(spec_citype, Type::trust_interfaces)->as_instance_type();
 665       improved_spec_type = improved_spec_type->join(spec_type)->join(TypePtr::NOTNULL);
 666       if (improved_spec_type->empty()) {
 667         continue;
 668       }
 669 
 670       const TypePtr* improved_type = TypeOopPtr::make(TypePtr::BotPTR, Type::Offset::bottom, TypeOopPtr::InstanceBot, improved_spec_type->is_ptr());
 671       improved_type = improved_type->join_speculative(t)->is_ptr();
 672       if (improved_type != t) {
 673         Node* cast = _gvn.transform(new CheckCastPPNode(control(), parm, improved_type, ConstraintCastNode::DependencyType::NonFloatingNarrowing));
 674         replace_in_map(parm, cast);
 675       }
 676     }
 677   }
 678 
 679   entry_map = map();  // capture any changes performed by method setup code
 680   assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");
 681 
 682   // We begin parsing as if we have just encountered a jump to the
 683   // method entry.
 684   Block* entry_block = start_block();
 685   assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
 686   set_map_clone(entry_map);
 687   merge_common(entry_block, entry_block->next_path_num());
 688 
 689 #ifndef PRODUCT
 690   BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
 691   set_parse_histogram( parse_histogram_obj );
 692 #endif
 693 
 694   // Parse all the basic blocks.
 695   do_all_blocks();
 696 
 697   // Check for bailouts during conversion to graph
 698   if (failing()) {

 844 void Parse::build_exits() {
 845   // make a clone of caller to prevent sharing of side-effects
 846   _exits.set_map(_exits.clone_map());
 847   _exits.clean_stack(_exits.sp());
 848   _exits.sync_jvms();
 849 
 850   RegionNode* region = new RegionNode(1);
 851   record_for_igvn(region);
 852   gvn().set_type_bottom(region);
 853   _exits.set_control(region);
 854 
 855   // Note:  iophi and memphi are not transformed until do_exits.
 856   Node* iophi  = new PhiNode(region, Type::ABIO);
 857   Node* memphi = new PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
 858   gvn().set_type_bottom(iophi);
 859   gvn().set_type_bottom(memphi);
 860   _exits.set_i_o(iophi);
 861   _exits.set_all_memory(memphi);
 862 
 863   // Add a return value to the exit state.  (Do not push it yet.)
 864   if (tf()->range_sig()->cnt() > TypeFunc::Parms) {
 865     const Type* ret_type = tf()->range_sig()->field_at(TypeFunc::Parms);
 866     if (ret_type->isa_int()) {
 867       BasicType ret_bt = method()->return_type()->basic_type();
 868       if (ret_bt == T_BOOLEAN ||
 869           ret_bt == T_CHAR ||
 870           ret_bt == T_BYTE ||
 871           ret_bt == T_SHORT) {
 872         ret_type = TypeInt::INT;
 873       }
 874     }
 875 
 876     // Don't "bind" an unloaded return klass to the ret_phi. If the klass
 877     // becomes loaded during the subsequent parsing, the loaded and unloaded
 878     // types will not join when we transform and push in do_exits().
 879     const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
 880     if (ret_oop_type && !ret_oop_type->is_loaded()) {
 881       ret_type = TypeOopPtr::BOTTOM;
 882     }
 883     int         ret_size = type2size[ret_type->basic_type()];
 884     Node*       ret_phi  = new PhiNode(region, ret_type);
 885     gvn().set_type_bottom(ret_phi);
 886     _exits.ensure_stack(ret_size);
 887     assert((int)(tf()->range_sig()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
 888     assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
 889     _exits.set_argument(0, ret_phi);  // here is where the parser finds it
 890     // Note:  ret_phi is not yet pushed, until do_exits.
 891   }
 892 }
 893 

 894 //----------------------------build_start_state-------------------------------
 895 // Construct a state which contains only the incoming arguments from an
 896 // unknown caller.  The method & bci will be null & InvocationEntryBci.
 897 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
 898   int        arg_size = tf->domain_sig()->cnt();
 899   int        max_size = MAX2(arg_size, (int)tf->range_cc()->cnt());
 900   JVMState*  jvms     = new (this) JVMState(max_size - TypeFunc::Parms);
 901   SafePointNode* map  = new SafePointNode(max_size, jvms);
 902   jvms->set_map(map);
 903   record_for_igvn(map);
 904   assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
 905   Node_Notes* old_nn = default_node_notes();
 906   if (old_nn != nullptr && has_method()) {
 907     Node_Notes* entry_nn = old_nn->clone(this);
 908     JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
 909     entry_jvms->set_offsets(0);
 910     entry_jvms->set_bci(entry_bci());
 911     entry_nn->set_jvms(entry_jvms);
 912     set_default_node_notes(entry_nn);
 913   }
 914   PhaseGVN& gvn = *initial_gvn();
 915   uint i = 0;
 916   int arg_num = 0;
 917   for (uint j = 0; i < (uint)arg_size; i++) {
 918     const Type* t = tf->domain_sig()->field_at(i);
 919     Node* parm = nullptr;
 920     if (t->is_inlinetypeptr() && method()->is_scalarized_arg(arg_num)) {
 921       // Inline type arguments are not passed by reference: we get an argument per
 922       // field of the inline type. Build InlineTypeNodes from the inline type arguments.
 923       GraphKit kit(jvms, &gvn);
 924       kit.set_control(map->control());
 925       Node* old_mem = map->memory();
 926       // Use immutable memory for inline type loads and restore it below
 927       kit.set_all_memory(C->immutable_memory());
 928       parm = InlineTypeNode::make_from_multi(&kit, start, t->inline_klass(), j, /* in= */ true, /* null_free= */ !t->maybe_null());
 929       map->set_control(kit.control());
 930       map->set_memory(old_mem);
 931     } else {
 932       parm = gvn.transform(new ParmNode(start, j++));
 933     }
 934     map->init_req(i, parm);
 935     // Record all these guys for later GVN.
 936     record_for_igvn(parm);
 937     if (i >= TypeFunc::Parms && t != Type::HALF) {
 938       arg_num++;
 939     }
 940   }
 941   for (; i < map->req(); i++) {
 942     map->init_req(i, top());
 943   }
 944   assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
 945   set_default_node_notes(old_nn);

 946   return jvms;
 947 }
 948 
 949 //-----------------------------make_node_notes---------------------------------
 950 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
 951   if (caller_nn == nullptr)  return nullptr;
 952   Node_Notes* nn = caller_nn->clone(C);
 953   JVMState* caller_jvms = nn->jvms();
 954   JVMState* jvms = new (C) JVMState(method(), caller_jvms);
 955   jvms->set_offsets(0);
 956   jvms->set_bci(_entry_bci);
 957   nn->set_jvms(jvms);
 958   return nn;
 959 }
 960 
 961 
 962 //--------------------------return_values--------------------------------------
 963 void Compile::return_values(JVMState* jvms) {
 964   GraphKit kit(jvms);
 965   Node* ret = new ReturnNode(TypeFunc::Parms,
 966                              kit.control(),
 967                              kit.i_o(),
 968                              kit.reset_memory(),
 969                              kit.frameptr(),
 970                              kit.returnadr());
 971   // Add zero or 1 return values
 972   int ret_size = tf()->range_sig()->cnt() - TypeFunc::Parms;
 973   if (ret_size > 0) {
 974     kit.inc_sp(-ret_size);  // pop the return value(s)
 975     kit.sync_jvms();
 976     Node* res = kit.argument(0);
 977     if (tf()->returns_inline_type_as_fields()) {
 978       // Multiple return values (inline type fields): add as many edges
 979       // to the Return node as returned values.
 980       InlineTypeNode* vt = res->as_InlineType();
 981       ret->add_req_batch(nullptr, tf()->range_cc()->cnt() - TypeFunc::Parms);
 982       if (vt->is_allocated(&kit.gvn()) && !StressCallingConvention) {
 983         ret->init_req(TypeFunc::Parms, vt);
 984       } else {
 985         // Return the tagged klass pointer to signal scalarization to the caller
 986         Node* tagged_klass = vt->tagged_klass(kit.gvn());
 987         // Return null if the inline type is null (null marker field is not set)
 988         Node* conv   = kit.gvn().transform(new ConvI2LNode(vt->get_null_marker()));
 989         Node* shl    = kit.gvn().transform(new LShiftLNode(conv, kit.intcon(63)));
 990         Node* shr    = kit.gvn().transform(new RShiftLNode(shl, kit.intcon(63)));
 991         tagged_klass = kit.gvn().transform(new AndLNode(tagged_klass, shr));
 992         ret->init_req(TypeFunc::Parms, tagged_klass);
 993       }
 994       uint idx = TypeFunc::Parms + 1;
 995       vt->pass_fields(&kit, ret, idx, false, false);
 996     } else {
 997       ret->add_req(res);
 998       // Note:  The second dummy edge is not needed by a ReturnNode.
 999     }
1000   }
1001   // bind it to root
1002   root()->add_req(ret);
1003   record_for_igvn(ret);
1004   initial_gvn()->transform(ret);
1005 }
1006 
1007 //------------------------rethrow_exceptions-----------------------------------
1008 // Bind all exception states in the list into a single RethrowNode.
1009 void Compile::rethrow_exceptions(JVMState* jvms) {
1010   GraphKit kit(jvms);
1011   if (!kit.has_exceptions())  return;  // nothing to generate
1012   // Load my combined exception state into the kit, with all phis transformed:
1013   SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
1014   Node* ex_oop = kit.use_exception_state(ex_map);
1015   RethrowNode* exit = new RethrowNode(kit.control(),
1016                                       kit.i_o(), kit.reset_memory(),
1017                                       kit.frameptr(), kit.returnadr(),
1018                                       // like a return but with exception input
1019                                       ex_oop);

1103   //    to complete, we force all writes to complete.
1104   //
1105   // 2. Experimental VM option is used to force the barrier if any field
1106   //    was written out in the constructor.
1107   //
1108   // 3. On processors which are not CPU_MULTI_COPY_ATOMIC (e.g. PPC64),
1109   //    support_IRIW_for_not_multiple_copy_atomic_cpu selects that
1110   //    MemBarVolatile is used before volatile load instead of after volatile
1111   //    store, so there's no barrier after the store.
1112   //    We want to guarantee the same behavior as on platforms with total store
1113   //    order, although this is not required by the Java memory model.
1114   //    In this case, we want to enforce visibility of volatile field
1115   //    initializations which are performed in constructors.
1116   //    So as with finals, we add a barrier here.
1117   //
1118   // "All bets are off" unless the first publication occurs after a
1119   // normal return from the constructor.  We do not attempt to detect
1120   // such unusual early publications.  But no barrier is needed on
1121   // exceptional returns, since they cannot publish normally.
1122   //
1123   if ((method()->is_object_constructor() || method()->is_class_initializer()) &&
1124        (wrote_final() || wrote_stable() ||
1125          (AlwaysSafeConstructors && wrote_fields()) ||
1126          (support_IRIW_for_not_multiple_copy_atomic_cpu && wrote_volatile()))) {
1127     Node* recorded_alloc = alloc_with_final_or_stable();
1128     _exits.insert_mem_bar(UseStoreStoreForCtor ? Op_MemBarStoreStore : Op_MemBarRelease,
1129                           recorded_alloc);
1130 
1131     // If Memory barrier is created for final fields write
1132     // and allocation node does not escape the initialize method,
1133     // then barrier introduced by allocation node can be removed.
1134     if (DoEscapeAnalysis && (recorded_alloc != nullptr)) {
1135       AllocateNode* alloc = AllocateNode::Ideal_allocation(recorded_alloc);
1136       alloc->compute_MemBar_redundancy(method());
1137     }
1138     if (PrintOpto && (Verbose || WizardMode)) {
1139       method()->print_name();
1140       tty->print_cr(" writes finals/@Stable and needs a memory barrier");
1141     }
1142   }
1143 
1144   for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
1145     // transform each slice of the original memphi:
1146     mms.set_memory(_gvn.transform(mms.memory()));
1147   }
1148   // Clean up input MergeMems created by transforming the slices
1149   _gvn.transform(_exits.merged_memory());
1150 
1151   if (tf()->range_sig()->cnt() > TypeFunc::Parms) {
1152     const Type* ret_type = tf()->range_sig()->field_at(TypeFunc::Parms);
1153     Node*       ret_phi  = _gvn.transform( _exits.argument(0) );
1154     if (!_exits.control()->is_top() && _gvn.type(ret_phi)->empty()) {
1155       // If the type we set for the ret_phi in build_exits() is too optimistic and
1156       // the ret_phi is top now, there's an extremely small chance that it may be due to class
1157       // loading.  It could also be due to an error, so mark this method as not compilable because
1158       // otherwise this could lead to an infinite compile loop.
1159       // In any case, this code path is rarely (and never in my testing) reached.
1160       C->record_method_not_compilable("Can't determine return type.");
1161       return;
1162     }
1163     if (ret_type->isa_int()) {
1164       BasicType ret_bt = method()->return_type()->basic_type();
1165       ret_phi = mask_int_value(ret_phi, ret_bt, &_gvn);
1166     }
1167     _exits.push_node(ret_type->basic_type(), ret_phi);
1168   }
1169 
1170   // Note:  Logic for creating and optimizing the ReturnNode is in Compile.
1171 
1172   // Unlock along the exceptional paths.

1226 
1227 //-----------------------------create_entry_map-------------------------------
1228 // Initialize our parser map to contain the types at method entry.
1229 // For OSR, the map contains a single RawPtr parameter.
1230 // Initial monitor locking for sync. methods is performed by do_method_entry.
1231 SafePointNode* Parse::create_entry_map() {
1232   // Check for really stupid bail-out cases.
1233   uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
1234   if (len >= 32760) {
1235     // Bailout expected, this is a very rare edge case.
1236     C->record_method_not_compilable("too many local variables");
1237     return nullptr;
1238   }
1239 
1240   // clear current replaced nodes that are of no use from here on (map was cloned in build_exits).
1241   _caller->map()->delete_replaced_nodes();
1242 
1243   // If this is an inlined method, we may have to do a receiver null check.
1244   if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
1245     GraphKit kit(_caller);
1246     Node* receiver = kit.argument(0);
1247     Node* null_free = kit.null_check_receiver_before_call(method());
1248     _caller = kit.transfer_exceptions_into_jvms();
1249 
1250     if (kit.stopped()) {
1251       _exits.add_exception_states_from(_caller);
1252       _exits.set_jvms(_caller);
1253       return nullptr;
1254     }
1255   }
1256 
1257   assert(method() != nullptr, "parser must have a method");
1258 
1259   // Create an initial safepoint to hold JVM state during parsing
1260   JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : nullptr);
1261   set_map(new SafePointNode(len, jvms));
1262 
1263   // Capture receiver info for compiled lambda forms.
1264   if (method()->is_compiled_lambda_form()) {
1265     ciInstance* recv_info = _caller->compute_receiver_info(method());
1266     jvms->set_receiver_info(recv_info);
1267   }
1268 
1269   jvms->set_map(map());

1273   SafePointNode* inmap = _caller->map();
1274   assert(inmap != nullptr, "must have inmap");
1275   // In case of null check on receiver above
1276   map()->transfer_replaced_nodes_from(inmap, _new_idx);
1277 
1278   uint i;
1279 
1280   // Pass thru the predefined input parameters.
1281   for (i = 0; i < TypeFunc::Parms; i++) {
1282     map()->init_req(i, inmap->in(i));
1283   }
1284 
1285   if (depth() == 1) {
1286     assert(map()->memory()->Opcode() == Op_Parm, "");
1287     // Insert the memory aliasing node
1288     set_all_memory(reset_memory());
1289   }
1290   assert(merged_memory(), "");
1291 
1292   // Now add the locals which are initially bound to arguments:
1293   uint arg_size = tf()->domain_sig()->cnt();
1294   ensure_stack(arg_size - TypeFunc::Parms);  // OSR methods have funny args
1295   for (i = TypeFunc::Parms; i < arg_size; i++) {
1296     map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
1297   }
1298 
1299   // Clear out the rest of the map (locals and stack)
1300   for (i = arg_size; i < len; i++) {
1301     map()->init_req(i, top());
1302   }
1303 
1304   SafePointNode* entry_map = stop();
1305   return entry_map;
1306 }
1307 
1308 //-----------------------------do_method_entry--------------------------------
1309 // Emit any code needed in the pseudo-block before BCI zero.
1310 // The main thing to do is lock the receiver of a synchronized method.
1311 void Parse::do_method_entry() {
1312   set_parse_bci(InvocationEntryBci); // Pseudo-BCP
1313   set_sp(0);                         // Java Stack Pointer
1314 
1315   NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
1316 
1317   // Check if we need a membar at the beginning of the java.lang.Object
1318   // constructor to satisfy the memory model for strict fields.
1319   if (Arguments::is_valhalla_enabled() && method()->intrinsic_id() == vmIntrinsics::_Object_init) {
1320     Node* receiver_obj = local(0);
1321     const TypeInstPtr* receiver_type = _gvn.type(receiver_obj)->isa_instptr();
1322     // If there's no exact type, check if the declared type has no implementors and add a dependency
1323     const TypeKlassPtr* klass_ptr = receiver_type->as_klass_type(/* try_for_exact= */ true);
1324     ciType* klass = klass_ptr->klass_is_exact() ? klass_ptr->exact_klass() : nullptr;
1325     if (klass != nullptr && klass->is_instance_klass()) {
1326       // Exact receiver type, check if there is a strict field
1327       ciInstanceKlass* holder = klass->as_instance_klass();
1328       for (int i = 0; i < holder->nof_nonstatic_fields(); i++) {
1329         ciField* field = holder->nonstatic_field_at(i);
1330         if (field->is_strict()) {
1331           // Found a strict field, a membar is needed
1332           AllocateNode* alloc = AllocateNode::Ideal_allocation(receiver_obj);
1333           insert_mem_bar(UseStoreStoreForCtor ? Op_MemBarStoreStore : Op_MemBarRelease, receiver_obj);
1334           if (DoEscapeAnalysis && (alloc != nullptr)) {
1335             alloc->compute_MemBar_redundancy(method());
1336           }
1337           break;
1338         }
1339       }
1340     } else if (klass == nullptr) {
1341       // We can't statically determine the type of the receiver and therefore need
1342       // to put a membar here because it could have a strict field.
1343       insert_mem_bar(UseStoreStoreForCtor ? Op_MemBarStoreStore : Op_MemBarRelease);
1344     }
1345   }
1346 
1347   if (C->env()->dtrace_method_probes()) {
1348     make_dtrace_method_entry(method());
1349   }
1350 
1351 #ifdef ASSERT
1352   // Narrow receiver type when it is too broad for the method being parsed.
1353   if (!method()->is_static()) {
1354     ciInstanceKlass* callee_holder = method()->holder();
1355     const Type* holder_type = TypeInstPtr::make(TypePtr::BotPTR, callee_holder, Type::trust_interfaces);
1356 
1357     Node* receiver_obj = local(0);
1358     const TypeInstPtr* receiver_type = _gvn.type(receiver_obj)->isa_instptr();
1359 
1360     if (receiver_type != nullptr && !receiver_type->higher_equal(holder_type)) {
1361       // Receiver should always be a subtype of callee holder.
1362       // But, since C2 type system doesn't properly track interfaces,
1363       // the invariant can't be expressed in the type system for default methods.
1364       // Example: for unrelated C <: I and D <: I, (C `meet` D) = Object </: I.
1365       assert(callee_holder->is_interface(), "missing subtype check");
1366 

1376 
1377   // If the method is synchronized, we need to construct a lock node, attach
1378   // it to the Start node, and pin it there.
1379   if (method()->is_synchronized()) {
1380     // Insert a FastLockNode right after the Start which takes as arguments
1381     // the current thread pointer, the "this" pointer & the address of the
1382     // stack slot pair used for the lock.  The "this" pointer is a projection
1383     // off the start node, but the locking spot has to be constructed by
1384     // creating a ConLNode of 0, and boxing it with a BoxLockNode.  The BoxLockNode
1385     // becomes the second argument to the FastLockNode call.  The
1386     // FastLockNode becomes the new control parent to pin it to the start.
1387 
1388     // Setup Object Pointer
1389     Node *lock_obj = nullptr;
1390     if (method()->is_static()) {
1391       ciInstance* mirror = _method->holder()->java_mirror();
1392       const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1393       lock_obj = makecon(t_lock);
1394     } else {                  // Else pass the "this" pointer,
1395       lock_obj = local(0);    // which is Parm0 from StartNode
1396       assert(!_gvn.type(lock_obj)->make_oopptr()->can_be_inline_type(), "can't be an inline type");
1397     }
1398     // Clear out dead values from the debug info.
1399     kill_dead_locals();
1400     // Build the FastLockNode
1401     _synch_lock = shared_lock(lock_obj);
1402     // Check for bailout in shared_lock
1403     if (failing()) { return; }
1404   }
1405 
1406   // Feed profiling data for parameters to the type system so it can
1407   // propagate it as speculative types
1408   record_profiled_parameters_for_speculation();
1409 }
1410 
1411 //------------------------------init_blocks------------------------------------
1412 // Initialize our parser map to contain the types/monitors at method entry.
1413 void Parse::init_blocks() {
1414   // Create the blocks.
1415   _block_count = flow()->block_count();
1416   _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);

1812 //--------------------handle_missing_successor---------------------------------
1813 void Parse::handle_missing_successor(int target_bci) {
1814 #ifndef PRODUCT
1815   Block* b = block();
1816   int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
1817   tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
1818 #endif
1819   ShouldNotReachHere();
1820 }
1821 
1822 //--------------------------merge_common---------------------------------------
1823 void Parse::merge_common(Parse::Block* target, int pnum) {
1824   if (TraceOptoParse) {
1825     tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
1826   }
1827 
1828   // Zap extra stack slots to top
1829   assert(sp() == target->start_sp(), "");
1830   clean_stack(sp());
1831 
1832   // Check for merge conflicts involving inline types
1833   JVMState* old_jvms = map()->jvms();
1834   int old_bci = bci();
1835   JVMState* tmp_jvms = old_jvms->clone_shallow(C);
1836   tmp_jvms->set_should_reexecute(true);
1837   tmp_jvms->bind_map(map());
1838   // Execution needs to restart a the next bytecode (entry of next
1839   // block)
1840   if (target->is_merged() ||
1841       pnum > PhiNode::Input ||
1842       target->is_handler() ||
1843       target->is_loop_head()) {
1844     set_parse_bci(target->start());
1845     for (uint j = TypeFunc::Parms; j < map()->req(); j++) {
1846       Node* n = map()->in(j);                 // Incoming change to target state.
1847       const Type* t = nullptr;
1848       if (tmp_jvms->is_loc(j)) {
1849         t = target->local_type_at(j - tmp_jvms->locoff());
1850       } else if (tmp_jvms->is_stk(j) && j < (uint)sp() + tmp_jvms->stkoff()) {
1851         t = target->stack_type_at(j - tmp_jvms->stkoff());
1852       }
1853       if (t != nullptr && t != Type::BOTTOM) {
1854         // An object can appear in the JVMS as either an oop or an InlineTypeNode. If the merge is
1855         // an InlineTypeNode, we need all the merge inputs to be InlineTypeNodes. Else, if the
1856         // merge is an oop, each merge input needs to be either an oop or an buffered
1857         // InlineTypeNode.
1858         if (!t->is_inlinetypeptr()) {
1859           // The merge cannot be an InlineTypeNode, ensure the input is buffered if it is an
1860           // InlineTypeNode
1861           if (n->is_InlineType()) {
1862             map()->set_req(j, n->as_InlineType()->buffer(this));
1863           }
1864         } else {
1865           // Since the merge is a value object, it can either be an oop or an InlineTypeNode
1866           if (!target->is_merged()) {
1867             // This is the first processed input of the merge. If it is an InlineTypeNode, the
1868             // merge will be an InlineTypeNode. Else, try to scalarize so the merge can be
1869             // scalarized as well. However, we cannot blindly scalarize an inline type oop here
1870             // since it may be larval
1871             if (!n->is_InlineType() && gvn().type(n)->is_zero_type()) {
1872               // Null constant implies that this is not a larval object
1873               map()->set_req(j, InlineTypeNode::make_null(gvn(), t->inline_klass()));
1874             }
1875           } else {
1876             Node* phi = target->start_map()->in(j);
1877             if (phi->is_InlineType()) {
1878               // Larval oops cannot be merged with non-larval ones, and since the merge point is
1879               // non-larval, n must be non-larval as well. As a result, we can scalarize n to merge
1880               // into phi
1881               if (!n->is_InlineType()) {
1882                 map()->set_req(j, InlineTypeNode::make_from_oop(this, n, t->inline_klass()));
1883               }
1884             } else {
1885               // The merge is an oop phi, ensure the input is buffered if it is an InlineTypeNode
1886               if (n->is_InlineType()) {
1887                 map()->set_req(j, n->as_InlineType()->buffer(this));
1888               }
1889             }
1890           }
1891         }
1892       }
1893     }
1894   }
1895   old_jvms->bind_map(map());
1896   set_parse_bci(old_bci);
1897 
1898   if (!target->is_merged()) {   // No prior mapping at this bci
1899     if (TraceOptoParse) { tty->print(" with empty state");  }
1900 
1901     // If this path is dead, do not bother capturing it as a merge.
1902     // It is "as if" we had 1 fewer predecessors from the beginning.
1903     if (stopped()) {
1904       if (TraceOptoParse)  tty->print_cr(", but path is dead and doesn't count");
1905       return;
1906     }
1907 
1908     // Make a region if we know there are multiple or unpredictable inputs.
1909     // (Also, if this is a plain fall-through, we might see another region,
1910     // which must not be allowed into this block's map.)
1911     if (pnum > PhiNode::Input         // Known multiple inputs.
1912         || target->is_handler()       // These have unpredictable inputs.
1913         || target->is_loop_head()     // Known multiple inputs
1914         || control()->is_Region()) {  // We must hide this guy.
1915 
1916       int current_bci = bci();
1917       set_parse_bci(target->start()); // Set target bci

1932       record_for_igvn(r);
1933       // zap all inputs to null for debugging (done in Node(uint) constructor)
1934       // for (int j = 1; j < edges+1; j++) { r->init_req(j, nullptr); }
1935       r->init_req(pnum, control());
1936       set_control(r);
1937       target->copy_irreducible_status_to(r, jvms());
1938       set_parse_bci(current_bci); // Restore bci
1939     }
1940 
1941     // Convert the existing Parser mapping into a mapping at this bci.
1942     store_state_to(target);
1943     assert(target->is_merged(), "do not come here twice");
1944 
1945   } else {                      // Prior mapping at this bci
1946     if (TraceOptoParse) {  tty->print(" with previous state"); }
1947 #ifdef ASSERT
1948     if (target->is_SEL_head()) {
1949       target->mark_merged_backedge(block());
1950     }
1951 #endif
1952 
1953     // We must not manufacture more phis if the target is already parsed.
1954     bool nophi = target->is_parsed();
1955 
1956     SafePointNode* newin = map();// Hang on to incoming mapping
1957     Block* save_block = block(); // Hang on to incoming block;
1958     load_state_from(target);    // Get prior mapping
1959 
1960     assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1961     assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1962     assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1963     assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1964 
1965     // Iterate over my current mapping and the old mapping.
1966     // Where different, insert Phi functions.
1967     // Use any existing Phi functions.
1968     assert(control()->is_Region(), "must be merging to a region");
1969     RegionNode* r = control()->as_Region();
1970 
1971     // Compute where to merge into
1972     // Merge incoming control path
1973     r->init_req(pnum, newin->control());
1974 
1975     if (pnum == 1) {            // Last merge for this Region?
1976       if (!block()->flow()->is_irreducible_loop_secondary_entry()) {
1977         Node* result = _gvn.transform(r);
1978         if (r != result && TraceOptoParse) {
1979           tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1980         }
1981       }
1982       record_for_igvn(r);
1983     }
1984 
1985     // Update all the non-control inputs to map:
1986     assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1987     bool check_elide_phi = target->is_SEL_backedge(save_block);
1988     bool last_merge = (pnum == PhiNode::Input);
1989     for (uint j = 1; j < newin->req(); j++) {
1990       Node* m = map()->in(j);   // Current state of target.
1991       Node* n = newin->in(j);   // Incoming change to target state.
1992       Node* phi;
1993       if (m->is_Phi() && m->as_Phi()->region() == r) {
1994         phi = m;
1995       } else if (m->is_InlineType() && m->as_InlineType()->has_phi_inputs(r)) {
1996         phi = m;
1997       } else {
1998         phi = nullptr;
1999       }
2000       if (m != n) {             // Different; must merge
2001         switch (j) {
2002         // Frame pointer and Return Address never changes
2003         case TypeFunc::FramePtr:// Drop m, use the original value
2004         case TypeFunc::ReturnAdr:
2005           break;
2006         case TypeFunc::Memory:  // Merge inputs to the MergeMem node
2007           assert(phi == nullptr, "the merge contains phis, not vice versa");
2008           merge_memory_edges(n->as_MergeMem(), pnum, nophi);
2009           continue;
2010         default:                // All normal stuff
2011           if (phi == nullptr) {
2012             const JVMState* jvms = map()->jvms();
2013             if (EliminateNestedLocks &&
2014                 jvms->is_mon(j) && jvms->is_monitor_box(j)) {
2015               // BoxLock nodes are not commoning when EliminateNestedLocks is on.
2016               // Use old BoxLock node as merged box.
2017               assert(newin->jvms()->is_monitor_box(j), "sanity");
2018               // This assert also tests that nodes are BoxLock.
2019               assert(BoxLockNode::same_slot(n, m), "sanity");

2026                 // Incremental Inlining before EA and Macro nodes elimination.
2027                 //
2028                 // Incremental Inlining is executed after IGVN optimizations
2029                 // during which BoxLock can be marked as Coarsened.
2030                 old_box->set_coarsened(); // Verifies state
2031                 old_box->set_unbalanced();
2032               }
2033               C->gvn_replace_by(n, m);
2034             } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
2035               phi = ensure_phi(j, nophi);
2036             }
2037           }
2038           break;
2039         }
2040       }
2041       // At this point, n might be top if:
2042       //  - there is no phi (because TypeFlow detected a conflict), or
2043       //  - the corresponding control edges is top (a dead incoming path)
2044       // It is a bug if we create a phi which sees a garbage value on a live path.
2045 
2046       // Merging two inline types?
2047       if (phi != nullptr && phi->is_InlineType()) {
2048         // Reload current state because it may have been updated by ensure_phi
2049         assert(phi == map()->in(j), "unexpected value in map");
2050         assert(phi->as_InlineType()->has_phi_inputs(r), "");
2051         InlineTypeNode* vtm = phi->as_InlineType(); // Current inline type
2052         InlineTypeNode* vtn = n->as_InlineType(); // Incoming inline type
2053         assert(vtm == phi, "Inline type should have Phi input");
2054 
2055 #ifdef ASSERT
2056         if (TraceOptoParse) {
2057           tty->print_cr("\nMerging inline types");
2058           tty->print_cr("Current:");
2059           vtm->dump(2);
2060           tty->print_cr("Incoming:");
2061           vtn->dump(2);
2062           tty->cr();
2063         }
2064 #endif
2065         // Do the merge
2066         vtm->merge_with(&_gvn, vtn, pnum, last_merge);
2067         if (last_merge) {
2068           map()->set_req(j, _gvn.transform(vtm));
2069           record_for_igvn(vtm);
2070         }
2071       } else if (phi != nullptr) {
2072         assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
2073         assert(phi->as_Phi()->region() == r, "");
2074         phi->set_req(pnum, n);  // Then add 'n' to the merge
2075         if (last_merge) {
2076           // Last merge for this Phi.
2077           // So far, Phis have had a reasonable type from ciTypeFlow.
2078           // Now _gvn will join that with the meet of current inputs.
2079           // BOTTOM is never permissible here, 'cause pessimistically
2080           // Phis of pointers cannot lose the basic pointer type.
2081           DEBUG_ONLY(const Type* bt1 = phi->bottom_type());
2082           assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
2083           map()->set_req(j, _gvn.transform(phi));
2084           DEBUG_ONLY(const Type* bt2 = phi->bottom_type());
2085           assert(bt2->higher_equal_speculative(bt1), "must be consistent with type-flow");
2086           record_for_igvn(phi);
2087         }
2088       }
2089     } // End of for all values to be merged
2090 
2091     if (last_merge && !r->in(0)) {         // The occasional useless Region

2092       assert(control() == r, "");
2093       set_control(r->nonnull_req());
2094     }
2095 
2096     map()->merge_replaced_nodes_with(newin);
2097 
2098     // newin has been subsumed into the lazy merge, and is now dead.
2099     set_block(save_block);
2100 
2101     stop();                     // done with this guy, for now
2102   }
2103 
2104   if (TraceOptoParse) {
2105     tty->print_cr(" on path %d", pnum);
2106   }
2107 
2108   // Done with this parser state.
2109   assert(stopped(), "");
2110 }
2111 

2223 
2224   // Add new path to the region.
2225   uint pnum = r->req();
2226   r->add_req(nullptr);
2227 
2228   for (uint i = 1; i < map->req(); i++) {
2229     Node* n = map->in(i);
2230     if (i == TypeFunc::Memory) {
2231       // Ensure a phi on all currently known memories.
2232       for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
2233         Node* phi = mms.memory();
2234         if (phi->is_Phi() && phi->as_Phi()->region() == r) {
2235           assert(phi->req() == pnum, "must be same size as region");
2236           phi->add_req(nullptr);
2237         }
2238       }
2239     } else {
2240       if (n->is_Phi() && n->as_Phi()->region() == r) {
2241         assert(n->req() == pnum, "must be same size as region");
2242         n->add_req(nullptr);
2243       } else if (n->is_InlineType() && n->as_InlineType()->has_phi_inputs(r)) {
2244         n->as_InlineType()->add_new_path(r);
2245       }
2246     }
2247   }
2248 
2249   return pnum;
2250 }
2251 
2252 //------------------------------ensure_phi-------------------------------------
2253 // Turn the idx'th entry of the current map into a Phi
2254 Node* Parse::ensure_phi(int idx, bool nocreate) {
2255   SafePointNode* map = this->map();
2256   Node* region = map->control();
2257   assert(region->is_Region(), "");
2258 
2259   Node* o = map->in(idx);
2260   assert(o != nullptr, "");
2261 
2262   if (o == top())  return nullptr; // TOP always merges into TOP
2263 
2264   if (o->is_Phi() && o->as_Phi()->region() == region) {
2265     return o->as_Phi();
2266   }
2267   InlineTypeNode* vt = o->isa_InlineType();
2268   if (vt != nullptr && vt->has_phi_inputs(region)) {
2269     return vt;
2270   }
2271 
2272   // Now use a Phi here for merging
2273   assert(!nocreate, "Cannot build a phi for a block already parsed.");
2274   const JVMState* jvms = map->jvms();
2275   const Type* t = nullptr;
2276   if (jvms->is_loc(idx)) {
2277     t = block()->local_type_at(idx - jvms->locoff());
2278   } else if (jvms->is_stk(idx)) {
2279     t = block()->stack_type_at(idx - jvms->stkoff());
2280   } else if (jvms->is_mon(idx)) {
2281     assert(!jvms->is_monitor_box(idx), "no phis for boxes");
2282     t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
2283   } else if ((uint)idx < TypeFunc::Parms) {
2284     t = o->bottom_type();  // Type::RETURN_ADDRESS or such-like.
2285   } else {
2286     assert(false, "no type information for this phi");
2287   }
2288 
2289   // If the type falls to bottom, then this must be a local that
2290   // is already dead or is mixing ints and oops or some such.
2291   // Forcing it to top makes it go dead.
2292   if (t == Type::BOTTOM) {
2293     map->set_req(idx, top());
2294     return nullptr;
2295   }
2296 
2297   // Do not create phis for top either.
2298   // A top on a non-null control flow must be an unused even after the.phi.
2299   if (t == Type::TOP || t == Type::HALF) {
2300     map->set_req(idx, top());
2301     return nullptr;
2302   }
2303 
2304   if (vt != nullptr && t->is_inlinetypeptr()) {
2305     // Inline types are merged by merging their field values.
2306     // Create a cloned InlineTypeNode with phi inputs that
2307     // represents the merged inline type and update the map.
2308     vt = vt->clone_with_phis(&_gvn, region);
2309     map->set_req(idx, vt);
2310     return vt;
2311   } else {
2312     PhiNode* phi = PhiNode::make(region, o, t);
2313     gvn().set_type(phi, t);
2314     if (C->do_escape_analysis()) record_for_igvn(phi);
2315     map->set_req(idx, phi);
2316     return phi;
2317   }
2318 }
2319 
2320 //--------------------------ensure_memory_phi----------------------------------
2321 // Turn the idx'th slice of the current memory into a Phi
2322 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
2323   MergeMemNode* mem = merged_memory();
2324   Node* region = control();
2325   assert(region->is_Region(), "");
2326 
2327   Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
2328   assert(o != nullptr && o != top(), "");
2329 
2330   PhiNode* phi;
2331   if (o->is_Phi() && o->as_Phi()->region() == region) {
2332     phi = o->as_Phi();
2333     if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
2334       // clone the shared base memory phi to make a new memory split
2335       assert(!nocreate, "Cannot build a phi for a block already parsed.");
2336       const Type* t = phi->bottom_type();
2337       const TypePtr* adr_type = C->get_adr_type(idx);

2427 // Add check to deoptimize once holder klass is fully initialized.
2428 void Parse::clinit_deopt() {
2429   assert(C->has_method(), "only for normal compilations");
2430   assert(depth() == 1, "only for main compiled method");
2431   assert(is_normal_parse(), "no barrier needed on osr entry");
2432   assert(!method()->holder()->is_not_initialized(), "initialization should have been started");
2433 
2434   set_parse_bci(0);
2435 
2436   Node* holder = makecon(TypeKlassPtr::make(method()->holder(), Type::trust_interfaces));
2437   guard_klass_being_initialized(holder);
2438 }
2439 
2440 //------------------------------return_current---------------------------------
2441 // Append current _map to _exit_return
2442 void Parse::return_current(Node* value) {
2443   if (method()->intrinsic_id() == vmIntrinsics::_Object_init) {
2444     call_register_finalizer();
2445   }
2446 
2447   // frame pointer is always same, already captured
2448   if (value != nullptr) {
2449     Node* phi = _exits.argument(0);
2450     const Type* return_type = phi->bottom_type();
2451     const TypeInstPtr* tr = return_type->isa_instptr();
2452     if ((tf()->returns_inline_type_as_fields() || (_caller->has_method() && !Compile::current()->inlining_incrementally())) &&
2453         return_type->is_inlinetypeptr()) {
2454       // Inline type is returned as fields, make sure it is scalarized
2455       if (!value->is_InlineType()) {
2456         value = InlineTypeNode::make_from_oop(this, value, return_type->inline_klass());
2457       }
2458       if (!_caller->has_method() || Compile::current()->inlining_incrementally()) {
2459         // Returning from root or an incrementally inlined method. Make sure all non-flat
2460         // fields are buffered and re-execute if allocation triggers deoptimization.
2461         PreserveReexecuteState preexecs(this);
2462         assert(tf()->returns_inline_type_as_fields(), "must be returned as fields");
2463         jvms()->set_should_reexecute(true);
2464         inc_sp(1);
2465         value = value->as_InlineType()->allocate_fields(this);
2466       }
2467     } else if (value->is_InlineType()) {
2468       // Inline type is returned as oop, make sure it is buffered and re-execute
2469       // if allocation triggers deoptimization.
2470       PreserveReexecuteState preexecs(this);
2471       jvms()->set_should_reexecute(true);
2472       inc_sp(1);
2473       value = value->as_InlineType()->buffer(this);
2474     }
2475     // ...else
2476     // If returning oops to an interface-return, there is a silent free
2477     // cast from oop to interface allowed by the Verifier. Make it explicit here.
2478     phi->add_req(value);
2479   }
2480 
2481   // Do not set_parse_bci, so that return goo is credited to the return insn.
2482   set_bci(InvocationEntryBci);
2483   if (method()->is_synchronized()) {
2484     shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
2485   }
2486   if (C->env()->dtrace_method_probes()) {
2487     make_dtrace_method_exit(method());
2488   }
2489 
2490   SafePointNode* exit_return = _exits.map();
2491   exit_return->in( TypeFunc::Control  )->add_req( control() );
2492   exit_return->in( TypeFunc::I_O      )->add_req( i_o    () );
2493   Node *mem = exit_return->in( TypeFunc::Memory   );
2494   for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
2495     if (mms.is_empty()) {
2496       // get a copy of the base memory, and patch just this one input
2497       const TypePtr* adr_type = mms.adr_type(C);
2498       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
2499       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
2500       gvn().set_type_bottom(phi);
2501       phi->del_req(phi->req()-1);  // prepare to re-patch
2502       mms.set_memory(phi);
2503     }
2504     mms.memory()->add_req(mms.memory2());
2505   }
2506 









2507   if (_first_return) {
2508     _exits.map()->transfer_replaced_nodes_from(map(), _new_idx);
2509     _first_return = false;
2510   } else {
2511     _exits.map()->merge_replaced_nodes_with(map());
2512   }
2513 
2514   stop_and_kill_map();          // This CFG path dies here
2515 }
2516 
2517 
2518 //------------------------------add_safepoint----------------------------------
2519 void Parse::add_safepoint() {
2520   uint parms = TypeFunc::Parms+1;
2521 
2522   // Clear out dead values from the debug info.
2523   kill_dead_locals();
2524 
2525   // Clone the JVM State
2526   SafePointNode *sfpnt = new SafePointNode(parms, nullptr);
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