1 /*
   2  * Copyright (c) 1997, 2023, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "asm/macroAssembler.hpp"
  27 #include "asm/macroAssembler.inline.hpp"
  28 #include "ci/ciReplay.hpp"
  29 #include "classfile/javaClasses.hpp"
  30 #include "code/exceptionHandlerTable.hpp"
  31 #include "code/nmethod.hpp"
  32 #include "compiler/compileBroker.hpp"
  33 #include "compiler/compileLog.hpp"
  34 #include "compiler/disassembler.hpp"
  35 #include "compiler/oopMap.hpp"
  36 #include "gc/shared/barrierSet.hpp"
  37 #include "gc/shared/c2/barrierSetC2.hpp"
  38 #include "jfr/jfrEvents.hpp"
  39 #include "jvm_io.h"
  40 #include "memory/allocation.hpp"
  41 #include "memory/resourceArea.hpp"
  42 #include "opto/addnode.hpp"
  43 #include "opto/block.hpp"
  44 #include "opto/c2compiler.hpp"
  45 #include "opto/callGenerator.hpp"
  46 #include "opto/callnode.hpp"
  47 #include "opto/castnode.hpp"
  48 #include "opto/cfgnode.hpp"
  49 #include "opto/chaitin.hpp"
  50 #include "opto/compile.hpp"
  51 #include "opto/connode.hpp"
  52 #include "opto/convertnode.hpp"
  53 #include "opto/divnode.hpp"
  54 #include "opto/escape.hpp"
  55 #include "opto/idealGraphPrinter.hpp"
  56 #include "opto/locknode.hpp"
  57 #include "opto/loopnode.hpp"
  58 #include "opto/machnode.hpp"
  59 #include "opto/macro.hpp"
  60 #include "opto/matcher.hpp"
  61 #include "opto/mathexactnode.hpp"
  62 #include "opto/memnode.hpp"
  63 #include "opto/mulnode.hpp"
  64 #include "opto/narrowptrnode.hpp"
  65 #include "opto/node.hpp"
  66 #include "opto/opcodes.hpp"
  67 #include "opto/output.hpp"
  68 #include "opto/parse.hpp"
  69 #include "opto/phaseX.hpp"
  70 #include "opto/rootnode.hpp"
  71 #include "opto/runtime.hpp"
  72 #include "opto/stringopts.hpp"
  73 #include "opto/type.hpp"
  74 #include "opto/vector.hpp"
  75 #include "opto/vectornode.hpp"
  76 #include "runtime/globals_extension.hpp"
  77 #include "runtime/sharedRuntime.hpp"
  78 #include "runtime/signature.hpp"
  79 #include "runtime/stubRoutines.hpp"
  80 #include "runtime/timer.hpp"
  81 #include "utilities/align.hpp"
  82 #include "utilities/copy.hpp"
  83 #include "utilities/macros.hpp"
  84 #include "utilities/resourceHash.hpp"
  85 
  86 // -------------------- Compile::mach_constant_base_node -----------------------
  87 // Constant table base node singleton.
  88 MachConstantBaseNode* Compile::mach_constant_base_node() {
  89   if (_mach_constant_base_node == nullptr) {
  90     _mach_constant_base_node = new MachConstantBaseNode();
  91     _mach_constant_base_node->add_req(C->root());
  92   }
  93   return _mach_constant_base_node;
  94 }
  95 
  96 
  97 /// Support for intrinsics.
  98 
  99 // Return the index at which m must be inserted (or already exists).
 100 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
 101 class IntrinsicDescPair {
 102  private:
 103   ciMethod* _m;
 104   bool _is_virtual;
 105  public:
 106   IntrinsicDescPair(ciMethod* m, bool is_virtual) : _m(m), _is_virtual(is_virtual) {}
 107   static int compare(IntrinsicDescPair* const& key, CallGenerator* const& elt) {
 108     ciMethod* m= elt->method();
 109     ciMethod* key_m = key->_m;
 110     if (key_m < m)      return -1;
 111     else if (key_m > m) return 1;
 112     else {
 113       bool is_virtual = elt->is_virtual();
 114       bool key_virtual = key->_is_virtual;
 115       if (key_virtual < is_virtual)      return -1;
 116       else if (key_virtual > is_virtual) return 1;
 117       else                               return 0;
 118     }
 119   }
 120 };
 121 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual, bool& found) {
 122 #ifdef ASSERT
 123   for (int i = 1; i < _intrinsics.length(); i++) {
 124     CallGenerator* cg1 = _intrinsics.at(i-1);
 125     CallGenerator* cg2 = _intrinsics.at(i);
 126     assert(cg1->method() != cg2->method()
 127            ? cg1->method()     < cg2->method()
 128            : cg1->is_virtual() < cg2->is_virtual(),
 129            "compiler intrinsics list must stay sorted");
 130   }
 131 #endif
 132   IntrinsicDescPair pair(m, is_virtual);
 133   return _intrinsics.find_sorted<IntrinsicDescPair*, IntrinsicDescPair::compare>(&pair, found);
 134 }
 135 
 136 void Compile::register_intrinsic(CallGenerator* cg) {
 137   bool found = false;
 138   int index = intrinsic_insertion_index(cg->method(), cg->is_virtual(), found);
 139   assert(!found, "registering twice");
 140   _intrinsics.insert_before(index, cg);
 141   assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
 142 }
 143 
 144 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
 145   assert(m->is_loaded(), "don't try this on unloaded methods");
 146   if (_intrinsics.length() > 0) {
 147     bool found = false;
 148     int index = intrinsic_insertion_index(m, is_virtual, found);
 149      if (found) {
 150       return _intrinsics.at(index);
 151     }
 152   }
 153   // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
 154   if (m->intrinsic_id() != vmIntrinsics::_none &&
 155       m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
 156     CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
 157     if (cg != nullptr) {
 158       // Save it for next time:
 159       register_intrinsic(cg);
 160       return cg;
 161     } else {
 162       gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
 163     }
 164   }
 165   return nullptr;
 166 }
 167 
 168 // Compile::make_vm_intrinsic is defined in library_call.cpp.
 169 
 170 #ifndef PRODUCT
 171 // statistics gathering...
 172 
 173 juint  Compile::_intrinsic_hist_count[vmIntrinsics::number_of_intrinsics()] = {0};
 174 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::number_of_intrinsics()] = {0};
 175 
 176 inline int as_int(vmIntrinsics::ID id) {
 177   return vmIntrinsics::as_int(id);
 178 }
 179 
 180 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
 181   assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
 182   int oflags = _intrinsic_hist_flags[as_int(id)];
 183   assert(flags != 0, "what happened?");
 184   if (is_virtual) {
 185     flags |= _intrinsic_virtual;
 186   }
 187   bool changed = (flags != oflags);
 188   if ((flags & _intrinsic_worked) != 0) {
 189     juint count = (_intrinsic_hist_count[as_int(id)] += 1);
 190     if (count == 1) {
 191       changed = true;           // first time
 192     }
 193     // increment the overall count also:
 194     _intrinsic_hist_count[as_int(vmIntrinsics::_none)] += 1;
 195   }
 196   if (changed) {
 197     if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
 198       // Something changed about the intrinsic's virtuality.
 199       if ((flags & _intrinsic_virtual) != 0) {
 200         // This is the first use of this intrinsic as a virtual call.
 201         if (oflags != 0) {
 202           // We already saw it as a non-virtual, so note both cases.
 203           flags |= _intrinsic_both;
 204         }
 205       } else if ((oflags & _intrinsic_both) == 0) {
 206         // This is the first use of this intrinsic as a non-virtual
 207         flags |= _intrinsic_both;
 208       }
 209     }
 210     _intrinsic_hist_flags[as_int(id)] = (jubyte) (oflags | flags);
 211   }
 212   // update the overall flags also:
 213   _intrinsic_hist_flags[as_int(vmIntrinsics::_none)] |= (jubyte) flags;
 214   return changed;
 215 }
 216 
 217 static char* format_flags(int flags, char* buf) {
 218   buf[0] = 0;
 219   if ((flags & Compile::_intrinsic_worked) != 0)    strcat(buf, ",worked");
 220   if ((flags & Compile::_intrinsic_failed) != 0)    strcat(buf, ",failed");
 221   if ((flags & Compile::_intrinsic_disabled) != 0)  strcat(buf, ",disabled");
 222   if ((flags & Compile::_intrinsic_virtual) != 0)   strcat(buf, ",virtual");
 223   if ((flags & Compile::_intrinsic_both) != 0)      strcat(buf, ",nonvirtual");
 224   if (buf[0] == 0)  strcat(buf, ",");
 225   assert(buf[0] == ',', "must be");
 226   return &buf[1];
 227 }
 228 
 229 void Compile::print_intrinsic_statistics() {
 230   char flagsbuf[100];
 231   ttyLocker ttyl;
 232   if (xtty != nullptr)  xtty->head("statistics type='intrinsic'");
 233   tty->print_cr("Compiler intrinsic usage:");
 234   juint total = _intrinsic_hist_count[as_int(vmIntrinsics::_none)];
 235   if (total == 0)  total = 1;  // avoid div0 in case of no successes
 236   #define PRINT_STAT_LINE(name, c, f) \
 237     tty->print_cr("  %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
 238   for (auto id : EnumRange<vmIntrinsicID>{}) {
 239     int   flags = _intrinsic_hist_flags[as_int(id)];
 240     juint count = _intrinsic_hist_count[as_int(id)];
 241     if ((flags | count) != 0) {
 242       PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
 243     }
 244   }
 245   PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[as_int(vmIntrinsics::_none)], flagsbuf));
 246   if (xtty != nullptr)  xtty->tail("statistics");
 247 }
 248 
 249 void Compile::print_statistics() {
 250   { ttyLocker ttyl;
 251     if (xtty != nullptr)  xtty->head("statistics type='opto'");
 252     Parse::print_statistics();
 253     PhaseStringOpts::print_statistics();
 254     PhaseCCP::print_statistics();
 255     PhaseRegAlloc::print_statistics();
 256     PhaseOutput::print_statistics();
 257     PhasePeephole::print_statistics();
 258     PhaseIdealLoop::print_statistics();
 259     ConnectionGraph::print_statistics();
 260     PhaseMacroExpand::print_statistics();
 261     if (xtty != nullptr)  xtty->tail("statistics");
 262   }
 263   if (_intrinsic_hist_flags[as_int(vmIntrinsics::_none)] != 0) {
 264     // put this under its own <statistics> element.
 265     print_intrinsic_statistics();
 266   }
 267 }
 268 #endif //PRODUCT
 269 
 270 void Compile::gvn_replace_by(Node* n, Node* nn) {
 271   for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
 272     Node* use = n->last_out(i);
 273     bool is_in_table = initial_gvn()->hash_delete(use);
 274     uint uses_found = 0;
 275     for (uint j = 0; j < use->len(); j++) {
 276       if (use->in(j) == n) {
 277         if (j < use->req())
 278           use->set_req(j, nn);
 279         else
 280           use->set_prec(j, nn);
 281         uses_found++;
 282       }
 283     }
 284     if (is_in_table) {
 285       // reinsert into table
 286       initial_gvn()->hash_find_insert(use);
 287     }
 288     record_for_igvn(use);
 289     i -= uses_found;    // we deleted 1 or more copies of this edge
 290   }
 291 }
 292 
 293 
 294 // Identify all nodes that are reachable from below, useful.
 295 // Use breadth-first pass that records state in a Unique_Node_List,
 296 // recursive traversal is slower.
 297 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
 298   int estimated_worklist_size = live_nodes();
 299   useful.map( estimated_worklist_size, nullptr );  // preallocate space
 300 
 301   // Initialize worklist
 302   if (root() != nullptr)  { useful.push(root()); }
 303   // If 'top' is cached, declare it useful to preserve cached node
 304   if (cached_top_node())  { useful.push(cached_top_node()); }
 305 
 306   // Push all useful nodes onto the list, breadthfirst
 307   for( uint next = 0; next < useful.size(); ++next ) {
 308     assert( next < unique(), "Unique useful nodes < total nodes");
 309     Node *n  = useful.at(next);
 310     uint max = n->len();
 311     for( uint i = 0; i < max; ++i ) {
 312       Node *m = n->in(i);
 313       if (not_a_node(m))  continue;
 314       useful.push(m);
 315     }
 316   }
 317 }
 318 
 319 // Update dead_node_list with any missing dead nodes using useful
 320 // list. Consider all non-useful nodes to be useless i.e., dead nodes.
 321 void Compile::update_dead_node_list(Unique_Node_List &useful) {
 322   uint max_idx = unique();
 323   VectorSet& useful_node_set = useful.member_set();
 324 
 325   for (uint node_idx = 0; node_idx < max_idx; node_idx++) {
 326     // If node with index node_idx is not in useful set,
 327     // mark it as dead in dead node list.
 328     if (!useful_node_set.test(node_idx)) {
 329       record_dead_node(node_idx);
 330     }
 331   }
 332 }
 333 
 334 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Unique_Node_List &useful) {
 335   int shift = 0;
 336   for (int i = 0; i < inlines->length(); i++) {
 337     CallGenerator* cg = inlines->at(i);
 338     if (useful.member(cg->call_node())) {
 339       if (shift > 0) {
 340         inlines->at_put(i - shift, cg);
 341       }
 342     } else {
 343       shift++; // skip over the dead element
 344     }
 345   }
 346   if (shift > 0) {
 347     inlines->trunc_to(inlines->length() - shift); // remove last elements from compacted array
 348   }
 349 }
 350 
 351 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Node* dead) {
 352   assert(dead != nullptr && dead->is_Call(), "sanity");
 353   int found = 0;
 354   for (int i = 0; i < inlines->length(); i++) {
 355     if (inlines->at(i)->call_node() == dead) {
 356       inlines->remove_at(i);
 357       found++;
 358       NOT_DEBUG( break; ) // elements are unique, so exit early
 359     }
 360   }
 361   assert(found <= 1, "not unique");
 362 }
 363 
 364 void Compile::remove_useless_nodes(GrowableArray<Node*>& node_list, Unique_Node_List& useful) {
 365   for (int i = node_list.length() - 1; i >= 0; i--) {
 366     Node* n = node_list.at(i);
 367     if (!useful.member(n)) {
 368       node_list.delete_at(i); // replaces i-th with last element which is known to be useful (already processed)
 369     }
 370   }
 371 }
 372 
 373 void Compile::remove_useless_node(Node* dead) {
 374   remove_modified_node(dead);
 375 
 376   // Constant node that has no out-edges and has only one in-edge from
 377   // root is usually dead. However, sometimes reshaping walk makes
 378   // it reachable by adding use edges. So, we will NOT count Con nodes
 379   // as dead to be conservative about the dead node count at any
 380   // given time.
 381   if (!dead->is_Con()) {
 382     record_dead_node(dead->_idx);
 383   }
 384   if (dead->is_macro()) {
 385     remove_macro_node(dead);
 386   }
 387   if (dead->is_expensive()) {
 388     remove_expensive_node(dead);
 389   }
 390   if (dead->Opcode() == Op_Opaque4) {
 391     remove_template_assertion_predicate_opaq(dead);
 392   }
 393   if (dead->for_post_loop_opts_igvn()) {
 394     remove_from_post_loop_opts_igvn(dead);
 395   }
 396   if (dead->is_Call()) {
 397     remove_useless_late_inlines(                &_late_inlines, dead);
 398     remove_useless_late_inlines(         &_string_late_inlines, dead);
 399     remove_useless_late_inlines(         &_boxing_late_inlines, dead);
 400     remove_useless_late_inlines(&_vector_reboxing_late_inlines, dead);
 401 
 402     if (dead->is_CallStaticJava()) {
 403       remove_unstable_if_trap(dead->as_CallStaticJava(), false);
 404     }
 405   }
 406   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
 407   bs->unregister_potential_barrier_node(dead);
 408 }
 409 
 410 // Disconnect all useless nodes by disconnecting those at the boundary.
 411 void Compile::disconnect_useless_nodes(Unique_Node_List& useful, Unique_Node_List& worklist) {
 412   uint next = 0;
 413   while (next < useful.size()) {
 414     Node *n = useful.at(next++);
 415     if (n->is_SafePoint()) {
 416       // We're done with a parsing phase. Replaced nodes are not valid
 417       // beyond that point.
 418       n->as_SafePoint()->delete_replaced_nodes();
 419     }
 420     // Use raw traversal of out edges since this code removes out edges
 421     int max = n->outcnt();
 422     for (int j = 0; j < max; ++j) {
 423       Node* child = n->raw_out(j);
 424       if (!useful.member(child)) {
 425         assert(!child->is_top() || child != top(),
 426                "If top is cached in Compile object it is in useful list");
 427         // Only need to remove this out-edge to the useless node
 428         n->raw_del_out(j);
 429         --j;
 430         --max;
 431       }
 432     }
 433     if (n->outcnt() == 1 && n->has_special_unique_user()) {
 434       assert(useful.member(n->unique_out()), "do not push a useless node");
 435       worklist.push(n->unique_out());
 436     }
 437   }
 438 
 439   remove_useless_nodes(_macro_nodes,        useful); // remove useless macro nodes
 440   remove_useless_nodes(_parse_predicate_opaqs, useful); // remove useless Parse Predicate opaque nodes
 441   remove_useless_nodes(_template_assertion_predicate_opaqs, useful); // remove useless Assertion Predicate opaque nodes
 442   remove_useless_nodes(_expensive_nodes,    useful); // remove useless expensive nodes
 443   remove_useless_nodes(_for_post_loop_igvn, useful); // remove useless node recorded for post loop opts IGVN pass
 444   remove_useless_unstable_if_traps(useful);          // remove useless unstable_if traps
 445   remove_useless_coarsened_locks(useful);            // remove useless coarsened locks nodes
 446 #ifdef ASSERT
 447   if (_modified_nodes != nullptr) {
 448     _modified_nodes->remove_useless_nodes(useful.member_set());
 449   }
 450 #endif
 451 
 452   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
 453   bs->eliminate_useless_gc_barriers(useful, this);
 454   // clean up the late inline lists
 455   remove_useless_late_inlines(                &_late_inlines, useful);
 456   remove_useless_late_inlines(         &_string_late_inlines, useful);
 457   remove_useless_late_inlines(         &_boxing_late_inlines, useful);
 458   remove_useless_late_inlines(&_vector_reboxing_late_inlines, useful);
 459   debug_only(verify_graph_edges(true/*check for no_dead_code*/);)
 460 }
 461 
 462 // ============================================================================
 463 //------------------------------CompileWrapper---------------------------------
 464 class CompileWrapper : public StackObj {
 465   Compile *const _compile;
 466  public:
 467   CompileWrapper(Compile* compile);
 468 
 469   ~CompileWrapper();
 470 };
 471 
 472 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
 473   // the Compile* pointer is stored in the current ciEnv:
 474   ciEnv* env = compile->env();
 475   assert(env == ciEnv::current(), "must already be a ciEnv active");
 476   assert(env->compiler_data() == nullptr, "compile already active?");
 477   env->set_compiler_data(compile);
 478   assert(compile == Compile::current(), "sanity");
 479 
 480   compile->set_type_dict(nullptr);
 481   compile->set_clone_map(new Dict(cmpkey, hashkey, _compile->comp_arena()));
 482   compile->clone_map().set_clone_idx(0);
 483   compile->set_type_last_size(0);
 484   compile->set_last_tf(nullptr, nullptr);
 485   compile->set_indexSet_arena(nullptr);
 486   compile->set_indexSet_free_block_list(nullptr);
 487   compile->init_type_arena();
 488   Type::Initialize(compile);
 489   _compile->begin_method();
 490   _compile->clone_map().set_debug(_compile->has_method() && _compile->directive()->CloneMapDebugOption);
 491 }
 492 CompileWrapper::~CompileWrapper() {
 493   // simulate crash during compilation
 494   assert(CICrashAt < 0 || _compile->compile_id() != CICrashAt, "just as planned");
 495 
 496   _compile->end_method();
 497   _compile->env()->set_compiler_data(nullptr);
 498 }
 499 
 500 
 501 //----------------------------print_compile_messages---------------------------
 502 void Compile::print_compile_messages() {
 503 #ifndef PRODUCT
 504   // Check if recompiling
 505   if (!subsume_loads() && PrintOpto) {
 506     // Recompiling without allowing machine instructions to subsume loads
 507     tty->print_cr("*********************************************************");
 508     tty->print_cr("** Bailout: Recompile without subsuming loads          **");
 509     tty->print_cr("*********************************************************");
 510   }
 511   if ((do_escape_analysis() != DoEscapeAnalysis) && PrintOpto) {
 512     // Recompiling without escape analysis
 513     tty->print_cr("*********************************************************");
 514     tty->print_cr("** Bailout: Recompile without escape analysis          **");
 515     tty->print_cr("*********************************************************");
 516   }
 517   if (do_iterative_escape_analysis() != DoEscapeAnalysis && PrintOpto) {
 518     // Recompiling without iterative escape analysis
 519     tty->print_cr("*********************************************************");
 520     tty->print_cr("** Bailout: Recompile without iterative escape analysis**");
 521     tty->print_cr("*********************************************************");
 522   }
 523   if ((eliminate_boxing() != EliminateAutoBox) && PrintOpto) {
 524     // Recompiling without boxing elimination
 525     tty->print_cr("*********************************************************");
 526     tty->print_cr("** Bailout: Recompile without boxing elimination       **");
 527     tty->print_cr("*********************************************************");
 528   }
 529   if ((do_locks_coarsening() != EliminateLocks) && PrintOpto) {
 530     // Recompiling without locks coarsening
 531     tty->print_cr("*********************************************************");
 532     tty->print_cr("** Bailout: Recompile without locks coarsening         **");
 533     tty->print_cr("*********************************************************");
 534   }
 535   if (env()->break_at_compile()) {
 536     // Open the debugger when compiling this method.
 537     tty->print("### Breaking when compiling: ");
 538     method()->print_short_name();
 539     tty->cr();
 540     BREAKPOINT;
 541   }
 542 
 543   if( PrintOpto ) {
 544     if (is_osr_compilation()) {
 545       tty->print("[OSR]%3d", _compile_id);
 546     } else {
 547       tty->print("%3d", _compile_id);
 548     }
 549   }
 550 #endif
 551 }
 552 
 553 #ifndef PRODUCT
 554 void Compile::print_ideal_ir(const char* phase_name) {
 555   // keep the following output all in one block
 556   // This output goes directly to the tty, not the compiler log.
 557   // To enable tools to match it up with the compilation activity,
 558   // be sure to tag this tty output with the compile ID.
 559 
 560   // Node dumping can cause a safepoint, which can break the tty lock.
 561   // Buffer all node dumps, so that all safepoints happen before we lock.
 562   ResourceMark rm;
 563   stringStream ss;
 564 
 565   if (_output == nullptr) {
 566     ss.print_cr("AFTER: %s", phase_name);
 567     // Print out all nodes in ascending order of index.
 568     root()->dump_bfs(MaxNodeLimit, nullptr, "+S$", &ss);
 569   } else {
 570     // Dump the node blockwise if we have a scheduling
 571     _output->print_scheduling(&ss);
 572   }
 573 
 574   // Check that the lock is not broken by a safepoint.
 575   NoSafepointVerifier nsv;
 576   ttyLocker ttyl;
 577   if (xtty != nullptr) {
 578     xtty->head("ideal compile_id='%d'%s compile_phase='%s'",
 579                compile_id(),
 580                is_osr_compilation() ? " compile_kind='osr'" : "",
 581                phase_name);
 582     xtty->print("%s", ss.as_string()); // print to tty would use xml escape encoding
 583     xtty->tail("ideal");
 584   } else {
 585     tty->print("%s", ss.as_string());
 586   }
 587 }
 588 #endif
 589 
 590 // ============================================================================
 591 //------------------------------Compile standard-------------------------------
 592 
 593 // Compile a method.  entry_bci is -1 for normal compilations and indicates
 594 // the continuation bci for on stack replacement.
 595 
 596 
 597 Compile::Compile( ciEnv* ci_env, ciMethod* target, int osr_bci,
 598                   Options options, DirectiveSet* directive)
 599                 : Phase(Compiler),
 600                   _compile_id(ci_env->compile_id()),
 601                   _options(options),
 602                   _method(target),
 603                   _entry_bci(osr_bci),
 604                   _ilt(nullptr),
 605                   _stub_function(nullptr),
 606                   _stub_name(nullptr),
 607                   _stub_entry_point(nullptr),
 608                   _max_node_limit(MaxNodeLimit),
 609                   _post_loop_opts_phase(false),
 610                   _inlining_progress(false),
 611                   _inlining_incrementally(false),
 612                   _do_cleanup(false),
 613                   _has_reserved_stack_access(target->has_reserved_stack_access()),
 614 #ifndef PRODUCT
 615                   _igv_idx(0),
 616                   _trace_opto_output(directive->TraceOptoOutputOption),
 617 #endif
 618                   _has_method_handle_invokes(false),
 619                   _clinit_barrier_on_entry(false),
 620                   _stress_seed(0),
 621                   _comp_arena(mtCompiler),
 622                   _barrier_set_state(BarrierSet::barrier_set()->barrier_set_c2()->create_barrier_state(comp_arena())),
 623                   _env(ci_env),
 624                   _directive(directive),
 625                   _log(ci_env->log()),
 626                   _intrinsics        (comp_arena(), 0, 0, nullptr),
 627                   _macro_nodes       (comp_arena(), 8, 0, nullptr),
 628                   _parse_predicate_opaqs (comp_arena(), 8, 0, nullptr),
 629                   _template_assertion_predicate_opaqs (comp_arena(), 8, 0, nullptr),
 630                   _expensive_nodes   (comp_arena(), 8, 0, nullptr),
 631                   _for_post_loop_igvn(comp_arena(), 8, 0, nullptr),
 632                   _unstable_if_traps (comp_arena(), 8, 0, nullptr),
 633                   _coarsened_locks   (comp_arena(), 8, 0, nullptr),
 634                   _congraph(nullptr),
 635                   NOT_PRODUCT(_igv_printer(nullptr) COMMA)
 636                   _dead_node_list(comp_arena()),
 637                   _dead_node_count(0),
 638                   _node_arena(mtCompiler),
 639                   _old_arena(mtCompiler),
 640                   _mach_constant_base_node(nullptr),
 641                   _Compile_types(mtCompiler),
 642                   _initial_gvn(nullptr),
 643                   _igvn_worklist(nullptr),
 644                   _types(nullptr),
 645                   _node_hash(nullptr),
 646                   _late_inlines(comp_arena(), 2, 0, nullptr),
 647                   _string_late_inlines(comp_arena(), 2, 0, nullptr),
 648                   _boxing_late_inlines(comp_arena(), 2, 0, nullptr),
 649                   _vector_reboxing_late_inlines(comp_arena(), 2, 0, nullptr),
 650                   _late_inlines_pos(0),
 651                   _number_of_mh_late_inlines(0),
 652                   _print_inlining_stream(new (mtCompiler) stringStream()),
 653                   _print_inlining_list(nullptr),
 654                   _print_inlining_idx(0),
 655                   _print_inlining_output(nullptr),
 656                   _replay_inline_data(nullptr),
 657                   _java_calls(0),
 658                   _inner_loops(0),
 659                   _interpreter_frame_size(0),
 660                   _output(nullptr)
 661 #ifndef PRODUCT
 662                   , _in_dump_cnt(0)
 663 #endif
 664 {
 665   C = this;
 666   CompileWrapper cw(this);
 667 
 668   if (CITimeVerbose) {
 669     tty->print(" ");
 670     target->holder()->name()->print();
 671     tty->print(".");
 672     target->print_short_name();
 673     tty->print("  ");
 674   }
 675   TraceTime t1("Total compilation time", &_t_totalCompilation, CITime, CITimeVerbose);
 676   TraceTime t2(nullptr, &_t_methodCompilation, CITime, false);
 677 
 678 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
 679   bool print_opto_assembly = directive->PrintOptoAssemblyOption;
 680   // We can always print a disassembly, either abstract (hex dump) or
 681   // with the help of a suitable hsdis library. Thus, we should not
 682   // couple print_assembly and print_opto_assembly controls.
 683   // But: always print opto and regular assembly on compile command 'print'.
 684   bool print_assembly = directive->PrintAssemblyOption;
 685   set_print_assembly(print_opto_assembly || print_assembly);
 686 #else
 687   set_print_assembly(false); // must initialize.
 688 #endif
 689 
 690 #ifndef PRODUCT
 691   set_parsed_irreducible_loop(false);
 692 #endif
 693 
 694   if (directive->ReplayInlineOption) {
 695     _replay_inline_data = ciReplay::load_inline_data(method(), entry_bci(), ci_env->comp_level());
 696   }
 697   set_print_inlining(directive->PrintInliningOption || PrintOptoInlining);
 698   set_print_intrinsics(directive->PrintIntrinsicsOption);
 699   set_has_irreducible_loop(true); // conservative until build_loop_tree() reset it
 700 
 701   if (ProfileTraps RTM_OPT_ONLY( || UseRTMLocking )) {
 702     // Make sure the method being compiled gets its own MDO,
 703     // so we can at least track the decompile_count().
 704     // Need MDO to record RTM code generation state.
 705     method()->ensure_method_data();
 706   }
 707 
 708   Init(/*do_aliasing=*/ true);
 709 
 710   print_compile_messages();
 711 
 712   _ilt = InlineTree::build_inline_tree_root();
 713 
 714   // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
 715   assert(num_alias_types() >= AliasIdxRaw, "");
 716 
 717 #define MINIMUM_NODE_HASH  1023
 718 
 719   // GVN that will be run immediately on new nodes
 720   uint estimated_size = method()->code_size()*4+64;
 721   estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
 722   _igvn_worklist = new (comp_arena()) Unique_Node_List(comp_arena());
 723   _types = new (comp_arena()) Type_Array(comp_arena());
 724   _node_hash = new (comp_arena()) NodeHash(comp_arena(), estimated_size);
 725   PhaseGVN gvn;
 726   set_initial_gvn(&gvn);
 727 
 728   print_inlining_init();
 729   { // Scope for timing the parser
 730     TracePhase tp("parse", &timers[_t_parser]);
 731 
 732     // Put top into the hash table ASAP.
 733     initial_gvn()->transform_no_reclaim(top());
 734 
 735     // Set up tf(), start(), and find a CallGenerator.
 736     CallGenerator* cg = nullptr;
 737     if (is_osr_compilation()) {
 738       const TypeTuple *domain = StartOSRNode::osr_domain();
 739       const TypeTuple *range = TypeTuple::make_range(method()->signature());
 740       init_tf(TypeFunc::make(domain, range));
 741       StartNode* s = new StartOSRNode(root(), domain);
 742       initial_gvn()->set_type_bottom(s);
 743       init_start(s);
 744       cg = CallGenerator::for_osr(method(), entry_bci());
 745     } else {
 746       // Normal case.
 747       init_tf(TypeFunc::make(method()));
 748       StartNode* s = new StartNode(root(), tf()->domain());
 749       initial_gvn()->set_type_bottom(s);
 750       init_start(s);
 751       if (method()->intrinsic_id() == vmIntrinsics::_Reference_get) {
 752         // With java.lang.ref.reference.get() we must go through the
 753         // intrinsic - even when get() is the root
 754         // method of the compile - so that, if necessary, the value in
 755         // the referent field of the reference object gets recorded by
 756         // the pre-barrier code.
 757         cg = find_intrinsic(method(), false);
 758       }
 759       if (cg == nullptr) {
 760         float past_uses = method()->interpreter_invocation_count();
 761         float expected_uses = past_uses;
 762         cg = CallGenerator::for_inline(method(), expected_uses);
 763       }
 764     }
 765     if (failing())  return;
 766     if (cg == nullptr) {
 767       const char* reason = InlineTree::check_can_parse(method());
 768       assert(reason != nullptr, "expect reason for parse failure");
 769       stringStream ss;
 770       ss.print("cannot parse method: %s", reason);
 771       record_method_not_compilable(ss.as_string());
 772       return;
 773     }
 774 
 775     gvn.set_type(root(), root()->bottom_type());
 776 
 777     JVMState* jvms = build_start_state(start(), tf());
 778     if ((jvms = cg->generate(jvms)) == nullptr) {
 779       if (!failure_reason_is(C2Compiler::retry_class_loading_during_parsing())) {
 780         assert(failure_reason() != nullptr, "expect reason for parse failure");
 781         stringStream ss;
 782         ss.print("method parse failed: %s", failure_reason());
 783         record_method_not_compilable(ss.as_string());
 784       }
 785       return;
 786     }
 787     GraphKit kit(jvms);
 788 
 789     if (!kit.stopped()) {
 790       // Accept return values, and transfer control we know not where.
 791       // This is done by a special, unique ReturnNode bound to root.
 792       return_values(kit.jvms());
 793     }
 794 
 795     if (kit.has_exceptions()) {
 796       // Any exceptions that escape from this call must be rethrown
 797       // to whatever caller is dynamically above us on the stack.
 798       // This is done by a special, unique RethrowNode bound to root.
 799       rethrow_exceptions(kit.transfer_exceptions_into_jvms());
 800     }
 801 
 802     assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()), "incremental inlining is off");
 803 
 804     if (_late_inlines.length() == 0 && !has_mh_late_inlines() && !failing() && has_stringbuilder()) {
 805       inline_string_calls(true);
 806     }
 807 
 808     if (failing())  return;
 809 
 810     print_method(PHASE_BEFORE_REMOVEUSELESS, 3);
 811 
 812     // Remove clutter produced by parsing.
 813     if (!failing()) {
 814       ResourceMark rm;
 815       PhaseRemoveUseless pru(initial_gvn(), *igvn_worklist());
 816     }
 817   }
 818 
 819   // Note:  Large methods are capped off in do_one_bytecode().
 820   if (failing())  return;
 821 
 822   // After parsing, node notes are no longer automagic.
 823   // They must be propagated by register_new_node_with_optimizer(),
 824   // clone(), or the like.
 825   set_default_node_notes(nullptr);
 826 
 827 #ifndef PRODUCT
 828   if (should_print_igv(1)) {
 829     _igv_printer->print_inlining();
 830   }
 831 #endif
 832 
 833   if (failing())  return;
 834   NOT_PRODUCT( verify_graph_edges(); )
 835 
 836   // If any phase is randomized for stress testing, seed random number
 837   // generation and log the seed for repeatability.
 838   if (StressLCM || StressGCM || StressIGVN || StressCCP || StressIncrementalInlining) {
 839     if (FLAG_IS_DEFAULT(StressSeed) || (FLAG_IS_ERGO(StressSeed) && directive->RepeatCompilationOption)) {
 840       _stress_seed = static_cast<uint>(Ticks::now().nanoseconds());
 841       FLAG_SET_ERGO(StressSeed, _stress_seed);
 842     } else {
 843       _stress_seed = StressSeed;
 844     }
 845     if (_log != nullptr) {
 846       _log->elem("stress_test seed='%u'", _stress_seed);
 847     }
 848   }
 849 
 850   // Now optimize
 851   Optimize();
 852   if (failing())  return;
 853   NOT_PRODUCT( verify_graph_edges(); )
 854 
 855 #ifndef PRODUCT
 856   if (should_print_ideal()) {
 857     print_ideal_ir("print_ideal");
 858   }
 859 #endif
 860 
 861 #ifdef ASSERT
 862   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
 863   bs->verify_gc_barriers(this, BarrierSetC2::BeforeCodeGen);
 864 #endif
 865 
 866   // Dump compilation data to replay it.
 867   if (directive->DumpReplayOption) {
 868     env()->dump_replay_data(_compile_id);
 869   }
 870   if (directive->DumpInlineOption && (ilt() != nullptr)) {
 871     env()->dump_inline_data(_compile_id);
 872   }
 873 
 874   // Now that we know the size of all the monitors we can add a fixed slot
 875   // for the original deopt pc.
 876   int next_slot = fixed_slots() + (sizeof(address) / VMRegImpl::stack_slot_size);
 877   set_fixed_slots(next_slot);
 878 
 879   // Compute when to use implicit null checks. Used by matching trap based
 880   // nodes and NullCheck optimization.
 881   set_allowed_deopt_reasons();
 882 
 883   // Now generate code
 884   Code_Gen();
 885 }
 886 
 887 //------------------------------Compile----------------------------------------
 888 // Compile a runtime stub
 889 Compile::Compile( ciEnv* ci_env,
 890                   TypeFunc_generator generator,
 891                   address stub_function,
 892                   const char *stub_name,
 893                   int is_fancy_jump,
 894                   bool pass_tls,
 895                   bool return_pc,
 896                   DirectiveSet* directive)
 897   : Phase(Compiler),
 898     _compile_id(0),
 899     _options(Options::for_runtime_stub()),
 900     _method(nullptr),
 901     _entry_bci(InvocationEntryBci),
 902     _stub_function(stub_function),
 903     _stub_name(stub_name),
 904     _stub_entry_point(nullptr),
 905     _max_node_limit(MaxNodeLimit),
 906     _post_loop_opts_phase(false),
 907     _inlining_progress(false),
 908     _inlining_incrementally(false),
 909     _has_reserved_stack_access(false),
 910 #ifndef PRODUCT
 911     _igv_idx(0),
 912     _trace_opto_output(directive->TraceOptoOutputOption),
 913 #endif
 914     _has_method_handle_invokes(false),
 915     _clinit_barrier_on_entry(false),
 916     _stress_seed(0),
 917     _comp_arena(mtCompiler),
 918     _barrier_set_state(BarrierSet::barrier_set()->barrier_set_c2()->create_barrier_state(comp_arena())),
 919     _env(ci_env),
 920     _directive(directive),
 921     _log(ci_env->log()),
 922     _congraph(nullptr),
 923     NOT_PRODUCT(_igv_printer(nullptr) COMMA)
 924     _dead_node_list(comp_arena()),
 925     _dead_node_count(0),
 926     _node_arena(mtCompiler),
 927     _old_arena(mtCompiler),
 928     _mach_constant_base_node(nullptr),
 929     _Compile_types(mtCompiler),
 930     _initial_gvn(nullptr),
 931     _igvn_worklist(nullptr),
 932     _types(nullptr),
 933     _node_hash(nullptr),
 934     _number_of_mh_late_inlines(0),
 935     _print_inlining_stream(new (mtCompiler) stringStream()),
 936     _print_inlining_list(nullptr),
 937     _print_inlining_idx(0),
 938     _print_inlining_output(nullptr),
 939     _replay_inline_data(nullptr),
 940     _java_calls(0),
 941     _inner_loops(0),
 942     _interpreter_frame_size(0),
 943     _output(nullptr),
 944 #ifndef PRODUCT
 945     _in_dump_cnt(0),
 946 #endif
 947     _allowed_reasons(0) {
 948   C = this;
 949 
 950   TraceTime t1(nullptr, &_t_totalCompilation, CITime, false);
 951   TraceTime t2(nullptr, &_t_stubCompilation, CITime, false);
 952 
 953 #ifndef PRODUCT
 954   set_print_assembly(PrintFrameConverterAssembly);
 955   set_parsed_irreducible_loop(false);
 956 #else
 957   set_print_assembly(false); // Must initialize.
 958 #endif
 959   set_has_irreducible_loop(false); // no loops
 960 
 961   CompileWrapper cw(this);
 962   Init(/*do_aliasing=*/ false);
 963   init_tf((*generator)());
 964 
 965   _igvn_worklist = new (comp_arena()) Unique_Node_List(comp_arena());
 966   _types = new (comp_arena()) Type_Array(comp_arena());
 967   _node_hash = new (comp_arena()) NodeHash(comp_arena(), 255);
 968   {
 969     PhaseGVN gvn;
 970     set_initial_gvn(&gvn);    // not significant, but GraphKit guys use it pervasively
 971     gvn.transform_no_reclaim(top());
 972 
 973     GraphKit kit;
 974     kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
 975   }
 976 
 977   NOT_PRODUCT( verify_graph_edges(); )
 978 
 979   Code_Gen();
 980 }
 981 
 982 //------------------------------Init-------------------------------------------
 983 // Prepare for a single compilation
 984 void Compile::Init(bool aliasing) {
 985   _do_aliasing = aliasing;
 986   _unique  = 0;
 987   _regalloc = nullptr;
 988 
 989   _tf      = nullptr;  // filled in later
 990   _top     = nullptr;  // cached later
 991   _matcher = nullptr;  // filled in later
 992   _cfg     = nullptr;  // filled in later
 993 
 994   IA32_ONLY( set_24_bit_selection_and_mode(true, false); )
 995 
 996   _node_note_array = nullptr;
 997   _default_node_notes = nullptr;
 998   DEBUG_ONLY( _modified_nodes = nullptr; ) // Used in Optimize()
 999 
1000   _immutable_memory = nullptr; // filled in at first inquiry
1001 
1002 #ifdef ASSERT
1003   _phase_optimize_finished = false;
1004   _exception_backedge = false;
1005   _type_verify = nullptr;
1006 #endif
1007 
1008   // Globally visible Nodes
1009   // First set TOP to null to give safe behavior during creation of RootNode
1010   set_cached_top_node(nullptr);
1011   set_root(new RootNode());
1012   // Now that you have a Root to point to, create the real TOP
1013   set_cached_top_node( new ConNode(Type::TOP) );
1014   set_recent_alloc(nullptr, nullptr);
1015 
1016   // Create Debug Information Recorder to record scopes, oopmaps, etc.
1017   env()->set_oop_recorder(new OopRecorder(env()->arena()));
1018   env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
1019   env()->set_dependencies(new Dependencies(env()));
1020 
1021   _fixed_slots = 0;
1022   set_has_split_ifs(false);
1023   set_has_loops(false); // first approximation
1024   set_has_stringbuilder(false);
1025   set_has_boxed_value(false);
1026   _trap_can_recompile = false;  // no traps emitted yet
1027   _major_progress = true; // start out assuming good things will happen
1028   set_has_unsafe_access(false);
1029   set_max_vector_size(0);
1030   set_clear_upper_avx(false);  //false as default for clear upper bits of ymm registers
1031   Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
1032   set_decompile_count(0);
1033 
1034   set_do_freq_based_layout(_directive->BlockLayoutByFrequencyOption);
1035   _loop_opts_cnt = LoopOptsCount;
1036   set_do_inlining(Inline);
1037   set_max_inline_size(MaxInlineSize);
1038   set_freq_inline_size(FreqInlineSize);
1039   set_do_scheduling(OptoScheduling);
1040 
1041   set_do_vector_loop(false);
1042   set_has_monitors(false);
1043 
1044   if (AllowVectorizeOnDemand) {
1045     if (has_method() && (_directive->VectorizeOption || _directive->VectorizeDebugOption)) {
1046       set_do_vector_loop(true);
1047       NOT_PRODUCT(if (do_vector_loop() && Verbose) {tty->print("Compile::Init: do vectorized loops (SIMD like) for method %s\n",  method()->name()->as_quoted_ascii());})
1048     } else if (has_method() && method()->name() != 0 &&
1049                method()->intrinsic_id() == vmIntrinsics::_forEachRemaining) {
1050       set_do_vector_loop(true);
1051     }
1052   }
1053   set_use_cmove(UseCMoveUnconditionally /* || do_vector_loop()*/); //TODO: consider do_vector_loop() mandate use_cmove unconditionally
1054   NOT_PRODUCT(if (use_cmove() && Verbose && has_method()) {tty->print("Compile::Init: use CMove without profitability tests for method %s\n",  method()->name()->as_quoted_ascii());})
1055 
1056   set_rtm_state(NoRTM); // No RTM lock eliding by default
1057   _max_node_limit = _directive->MaxNodeLimitOption;
1058 
1059 #if INCLUDE_RTM_OPT
1060   if (UseRTMLocking && has_method() && (method()->method_data_or_null() != nullptr)) {
1061     int rtm_state = method()->method_data()->rtm_state();
1062     if (method_has_option(CompileCommand::NoRTMLockEliding) || ((rtm_state & NoRTM) != 0)) {
1063       // Don't generate RTM lock eliding code.
1064       set_rtm_state(NoRTM);
1065     } else if (method_has_option(CompileCommand::UseRTMLockEliding) || ((rtm_state & UseRTM) != 0) || !UseRTMDeopt) {
1066       // Generate RTM lock eliding code without abort ratio calculation code.
1067       set_rtm_state(UseRTM);
1068     } else if (UseRTMDeopt) {
1069       // Generate RTM lock eliding code and include abort ratio calculation
1070       // code if UseRTMDeopt is on.
1071       set_rtm_state(ProfileRTM);
1072     }
1073   }
1074 #endif
1075   if (VM_Version::supports_fast_class_init_checks() && has_method() && !is_osr_compilation() && method()->needs_clinit_barrier()) {
1076     set_clinit_barrier_on_entry(true);
1077   }
1078   if (debug_info()->recording_non_safepoints()) {
1079     set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
1080                         (comp_arena(), 8, 0, nullptr));
1081     set_default_node_notes(Node_Notes::make(this));
1082   }
1083 
1084   const int grow_ats = 16;
1085   _max_alias_types = grow_ats;
1086   _alias_types   = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
1087   AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType,  grow_ats);
1088   Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
1089   {
1090     for (int i = 0; i < grow_ats; i++)  _alias_types[i] = &ats[i];
1091   }
1092   // Initialize the first few types.
1093   _alias_types[AliasIdxTop]->Init(AliasIdxTop, nullptr);
1094   _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
1095   _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
1096   _num_alias_types = AliasIdxRaw+1;
1097   // Zero out the alias type cache.
1098   Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
1099   // A null adr_type hits in the cache right away.  Preload the right answer.
1100   probe_alias_cache(nullptr)->_index = AliasIdxTop;
1101 }
1102 
1103 //---------------------------init_start----------------------------------------
1104 // Install the StartNode on this compile object.
1105 void Compile::init_start(StartNode* s) {
1106   if (failing())
1107     return; // already failing
1108   assert(s == start(), "");
1109 }
1110 
1111 /**
1112  * Return the 'StartNode'. We must not have a pending failure, since the ideal graph
1113  * can be in an inconsistent state, i.e., we can get segmentation faults when traversing
1114  * the ideal graph.
1115  */
1116 StartNode* Compile::start() const {
1117   assert (!failing(), "Must not have pending failure. Reason is: %s", failure_reason());
1118   for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
1119     Node* start = root()->fast_out(i);
1120     if (start->is_Start()) {
1121       return start->as_Start();
1122     }
1123   }
1124   fatal("Did not find Start node!");
1125   return nullptr;
1126 }
1127 
1128 //-------------------------------immutable_memory-------------------------------------
1129 // Access immutable memory
1130 Node* Compile::immutable_memory() {
1131   if (_immutable_memory != nullptr) {
1132     return _immutable_memory;
1133   }
1134   StartNode* s = start();
1135   for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
1136     Node *p = s->fast_out(i);
1137     if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
1138       _immutable_memory = p;
1139       return _immutable_memory;
1140     }
1141   }
1142   ShouldNotReachHere();
1143   return nullptr;
1144 }
1145 
1146 //----------------------set_cached_top_node------------------------------------
1147 // Install the cached top node, and make sure Node::is_top works correctly.
1148 void Compile::set_cached_top_node(Node* tn) {
1149   if (tn != nullptr)  verify_top(tn);
1150   Node* old_top = _top;
1151   _top = tn;
1152   // Calling Node::setup_is_top allows the nodes the chance to adjust
1153   // their _out arrays.
1154   if (_top != nullptr)     _top->setup_is_top();
1155   if (old_top != nullptr)  old_top->setup_is_top();
1156   assert(_top == nullptr || top()->is_top(), "");
1157 }
1158 
1159 #ifdef ASSERT
1160 uint Compile::count_live_nodes_by_graph_walk() {
1161   Unique_Node_List useful(comp_arena());
1162   // Get useful node list by walking the graph.
1163   identify_useful_nodes(useful);
1164   return useful.size();
1165 }
1166 
1167 void Compile::print_missing_nodes() {
1168 
1169   // Return if CompileLog is null and PrintIdealNodeCount is false.
1170   if ((_log == nullptr) && (! PrintIdealNodeCount)) {
1171     return;
1172   }
1173 
1174   // This is an expensive function. It is executed only when the user
1175   // specifies VerifyIdealNodeCount option or otherwise knows the
1176   // additional work that needs to be done to identify reachable nodes
1177   // by walking the flow graph and find the missing ones using
1178   // _dead_node_list.
1179 
1180   Unique_Node_List useful(comp_arena());
1181   // Get useful node list by walking the graph.
1182   identify_useful_nodes(useful);
1183 
1184   uint l_nodes = C->live_nodes();
1185   uint l_nodes_by_walk = useful.size();
1186 
1187   if (l_nodes != l_nodes_by_walk) {
1188     if (_log != nullptr) {
1189       _log->begin_head("mismatched_nodes count='%d'", abs((int) (l_nodes - l_nodes_by_walk)));
1190       _log->stamp();
1191       _log->end_head();
1192     }
1193     VectorSet& useful_member_set = useful.member_set();
1194     int last_idx = l_nodes_by_walk;
1195     for (int i = 0; i < last_idx; i++) {
1196       if (useful_member_set.test(i)) {
1197         if (_dead_node_list.test(i)) {
1198           if (_log != nullptr) {
1199             _log->elem("mismatched_node_info node_idx='%d' type='both live and dead'", i);
1200           }
1201           if (PrintIdealNodeCount) {
1202             // Print the log message to tty
1203               tty->print_cr("mismatched_node idx='%d' both live and dead'", i);
1204               useful.at(i)->dump();
1205           }
1206         }
1207       }
1208       else if (! _dead_node_list.test(i)) {
1209         if (_log != nullptr) {
1210           _log->elem("mismatched_node_info node_idx='%d' type='neither live nor dead'", i);
1211         }
1212         if (PrintIdealNodeCount) {
1213           // Print the log message to tty
1214           tty->print_cr("mismatched_node idx='%d' type='neither live nor dead'", i);
1215         }
1216       }
1217     }
1218     if (_log != nullptr) {
1219       _log->tail("mismatched_nodes");
1220     }
1221   }
1222 }
1223 void Compile::record_modified_node(Node* n) {
1224   if (_modified_nodes != nullptr && !_inlining_incrementally && !n->is_Con()) {
1225     _modified_nodes->push(n);
1226   }
1227 }
1228 
1229 void Compile::remove_modified_node(Node* n) {
1230   if (_modified_nodes != nullptr) {
1231     _modified_nodes->remove(n);
1232   }
1233 }
1234 #endif
1235 
1236 #ifndef PRODUCT
1237 void Compile::verify_top(Node* tn) const {
1238   if (tn != nullptr) {
1239     assert(tn->is_Con(), "top node must be a constant");
1240     assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
1241     assert(tn->in(0) != nullptr, "must have live top node");
1242   }
1243 }
1244 #endif
1245 
1246 
1247 ///-------------------Managing Per-Node Debug & Profile Info-------------------
1248 
1249 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
1250   guarantee(arr != nullptr, "");
1251   int num_blocks = arr->length();
1252   if (grow_by < num_blocks)  grow_by = num_blocks;
1253   int num_notes = grow_by * _node_notes_block_size;
1254   Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
1255   Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
1256   while (num_notes > 0) {
1257     arr->append(notes);
1258     notes     += _node_notes_block_size;
1259     num_notes -= _node_notes_block_size;
1260   }
1261   assert(num_notes == 0, "exact multiple, please");
1262 }
1263 
1264 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
1265   if (source == nullptr || dest == nullptr)  return false;
1266 
1267   if (dest->is_Con())
1268     return false;               // Do not push debug info onto constants.
1269 
1270 #ifdef ASSERT
1271   // Leave a bread crumb trail pointing to the original node:
1272   if (dest != nullptr && dest != source && dest->debug_orig() == nullptr) {
1273     dest->set_debug_orig(source);
1274   }
1275 #endif
1276 
1277   if (node_note_array() == nullptr)
1278     return false;               // Not collecting any notes now.
1279 
1280   // This is a copy onto a pre-existing node, which may already have notes.
1281   // If both nodes have notes, do not overwrite any pre-existing notes.
1282   Node_Notes* source_notes = node_notes_at(source->_idx);
1283   if (source_notes == nullptr || source_notes->is_clear())  return false;
1284   Node_Notes* dest_notes   = node_notes_at(dest->_idx);
1285   if (dest_notes == nullptr || dest_notes->is_clear()) {
1286     return set_node_notes_at(dest->_idx, source_notes);
1287   }
1288 
1289   Node_Notes merged_notes = (*source_notes);
1290   // The order of operations here ensures that dest notes will win...
1291   merged_notes.update_from(dest_notes);
1292   return set_node_notes_at(dest->_idx, &merged_notes);
1293 }
1294 
1295 
1296 //--------------------------allow_range_check_smearing-------------------------
1297 // Gating condition for coalescing similar range checks.
1298 // Sometimes we try 'speculatively' replacing a series of a range checks by a
1299 // single covering check that is at least as strong as any of them.
1300 // If the optimization succeeds, the simplified (strengthened) range check
1301 // will always succeed.  If it fails, we will deopt, and then give up
1302 // on the optimization.
1303 bool Compile::allow_range_check_smearing() const {
1304   // If this method has already thrown a range-check,
1305   // assume it was because we already tried range smearing
1306   // and it failed.
1307   uint already_trapped = trap_count(Deoptimization::Reason_range_check);
1308   return !already_trapped;
1309 }
1310 
1311 
1312 //------------------------------flatten_alias_type-----------------------------
1313 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
1314   assert(do_aliasing(), "Aliasing should be enabled");
1315   int offset = tj->offset();
1316   TypePtr::PTR ptr = tj->ptr();
1317 
1318   // Known instance (scalarizable allocation) alias only with itself.
1319   bool is_known_inst = tj->isa_oopptr() != nullptr &&
1320                        tj->is_oopptr()->is_known_instance();
1321 
1322   // Process weird unsafe references.
1323   if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
1324     assert(InlineUnsafeOps || StressReflectiveCode, "indeterminate pointers come only from unsafe ops");
1325     assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
1326     tj = TypeOopPtr::BOTTOM;
1327     ptr = tj->ptr();
1328     offset = tj->offset();
1329   }
1330 
1331   // Array pointers need some flattening
1332   const TypeAryPtr* ta = tj->isa_aryptr();
1333   if (ta && ta->is_stable()) {
1334     // Erase stability property for alias analysis.
1335     tj = ta = ta->cast_to_stable(false);
1336   }
1337   if( ta && is_known_inst ) {
1338     if ( offset != Type::OffsetBot &&
1339          offset > arrayOopDesc::length_offset_in_bytes() ) {
1340       offset = Type::OffsetBot; // Flatten constant access into array body only
1341       tj = ta = ta->
1342               remove_speculative()->
1343               cast_to_ptr_type(ptr)->
1344               with_offset(offset);
1345     }
1346   } else if (ta) {
1347     // For arrays indexed by constant indices, we flatten the alias
1348     // space to include all of the array body.  Only the header, klass
1349     // and array length can be accessed un-aliased.
1350     if( offset != Type::OffsetBot ) {
1351       if( ta->const_oop() ) { // MethodData* or Method*
1352         offset = Type::OffsetBot;   // Flatten constant access into array body
1353         tj = ta = ta->
1354                 remove_speculative()->
1355                 cast_to_ptr_type(ptr)->
1356                 cast_to_exactness(false)->
1357                 with_offset(offset);
1358       } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
1359         // range is OK as-is.
1360         tj = ta = TypeAryPtr::RANGE;
1361       } else if( offset == oopDesc::klass_offset_in_bytes() ) {
1362         tj = TypeInstPtr::KLASS; // all klass loads look alike
1363         ta = TypeAryPtr::RANGE; // generic ignored junk
1364         ptr = TypePtr::BotPTR;
1365       } else if( offset == oopDesc::mark_offset_in_bytes() ) {
1366         tj = TypeInstPtr::MARK;
1367         ta = TypeAryPtr::RANGE; // generic ignored junk
1368         ptr = TypePtr::BotPTR;
1369       } else {                  // Random constant offset into array body
1370         offset = Type::OffsetBot;   // Flatten constant access into array body
1371         tj = ta = ta->
1372                 remove_speculative()->
1373                 cast_to_ptr_type(ptr)->
1374                 cast_to_exactness(false)->
1375                 with_offset(offset);
1376       }
1377     }
1378     // Arrays of fixed size alias with arrays of unknown size.
1379     if (ta->size() != TypeInt::POS) {
1380       const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
1381       tj = ta = ta->
1382               remove_speculative()->
1383               cast_to_ptr_type(ptr)->
1384               with_ary(tary)->
1385               cast_to_exactness(false);
1386     }
1387     // Arrays of known objects become arrays of unknown objects.
1388     if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
1389       const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
1390       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,nullptr,false,offset);
1391     }
1392     if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
1393       const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
1394       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,nullptr,false,offset);
1395     }
1396     // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
1397     // cannot be distinguished by bytecode alone.
1398     if (ta->elem() == TypeInt::BOOL) {
1399       const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
1400       ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
1401       tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
1402     }
1403     // During the 2nd round of IterGVN, NotNull castings are removed.
1404     // Make sure the Bottom and NotNull variants alias the same.
1405     // Also, make sure exact and non-exact variants alias the same.
1406     if (ptr == TypePtr::NotNull || ta->klass_is_exact() || ta->speculative() != nullptr) {
1407       tj = ta = ta->
1408               remove_speculative()->
1409               cast_to_ptr_type(TypePtr::BotPTR)->
1410               cast_to_exactness(false)->
1411               with_offset(offset);
1412     }
1413   }
1414 
1415   // Oop pointers need some flattening
1416   const TypeInstPtr *to = tj->isa_instptr();
1417   if (to && to != TypeOopPtr::BOTTOM) {
1418     ciInstanceKlass* ik = to->instance_klass();
1419     if( ptr == TypePtr::Constant ) {
1420       if (ik != ciEnv::current()->Class_klass() ||
1421           offset < ik->layout_helper_size_in_bytes()) {
1422         // No constant oop pointers (such as Strings); they alias with
1423         // unknown strings.
1424         assert(!is_known_inst, "not scalarizable allocation");
1425         tj = to = to->
1426                 cast_to_instance_id(TypeOopPtr::InstanceBot)->
1427                 remove_speculative()->
1428                 cast_to_ptr_type(TypePtr::BotPTR)->
1429                 cast_to_exactness(false);
1430       }
1431     } else if( is_known_inst ) {
1432       tj = to; // Keep NotNull and klass_is_exact for instance type
1433     } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
1434       // During the 2nd round of IterGVN, NotNull castings are removed.
1435       // Make sure the Bottom and NotNull variants alias the same.
1436       // Also, make sure exact and non-exact variants alias the same.
1437       tj = to = to->
1438               remove_speculative()->
1439               cast_to_instance_id(TypeOopPtr::InstanceBot)->
1440               cast_to_ptr_type(TypePtr::BotPTR)->
1441               cast_to_exactness(false);
1442     }
1443     if (to->speculative() != nullptr) {
1444       tj = to = to->remove_speculative();
1445     }
1446     // Canonicalize the holder of this field
1447     if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
1448       // First handle header references such as a LoadKlassNode, even if the
1449       // object's klass is unloaded at compile time (4965979).
1450       if (!is_known_inst) { // Do it only for non-instance types
1451         tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, nullptr, offset);
1452       }
1453     } else if (offset < 0 || offset >= ik->layout_helper_size_in_bytes()) {
1454       // Static fields are in the space above the normal instance
1455       // fields in the java.lang.Class instance.
1456       if (ik != ciEnv::current()->Class_klass()) {
1457         to = nullptr;
1458         tj = TypeOopPtr::BOTTOM;
1459         offset = tj->offset();
1460       }
1461     } else {
1462       ciInstanceKlass *canonical_holder = ik->get_canonical_holder(offset);
1463       assert(offset < canonical_holder->layout_helper_size_in_bytes(), "");
1464       if (!ik->equals(canonical_holder) || tj->offset() != offset) {
1465         if( is_known_inst ) {
1466           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, nullptr, offset, to->instance_id());
1467         } else {
1468           tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, nullptr, offset);
1469         }
1470       }
1471     }
1472   }
1473 
1474   // Klass pointers to object array klasses need some flattening
1475   const TypeKlassPtr *tk = tj->isa_klassptr();
1476   if( tk ) {
1477     // If we are referencing a field within a Klass, we need
1478     // to assume the worst case of an Object.  Both exact and
1479     // inexact types must flatten to the same alias class so
1480     // use NotNull as the PTR.
1481     if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
1482       tj = tk = TypeInstKlassPtr::make(TypePtr::NotNull,
1483                                        env()->Object_klass(),
1484                                        offset);
1485     }
1486 
1487     if (tk->isa_aryklassptr() && tk->is_aryklassptr()->elem()->isa_klassptr()) {
1488       ciKlass* k = ciObjArrayKlass::make(env()->Object_klass());
1489       if (!k || !k->is_loaded()) {                  // Only fails for some -Xcomp runs
1490         tj = tk = TypeInstKlassPtr::make(TypePtr::NotNull, env()->Object_klass(), offset);
1491       } else {
1492         tj = tk = TypeAryKlassPtr::make(TypePtr::NotNull, tk->is_aryklassptr()->elem(), k, offset);
1493       }
1494     }
1495 
1496     // Check for precise loads from the primary supertype array and force them
1497     // to the supertype cache alias index.  Check for generic array loads from
1498     // the primary supertype array and also force them to the supertype cache
1499     // alias index.  Since the same load can reach both, we need to merge
1500     // these 2 disparate memories into the same alias class.  Since the
1501     // primary supertype array is read-only, there's no chance of confusion
1502     // where we bypass an array load and an array store.
1503     int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
1504     if (offset == Type::OffsetBot ||
1505         (offset >= primary_supers_offset &&
1506          offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
1507         offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
1508       offset = in_bytes(Klass::secondary_super_cache_offset());
1509       tj = tk = tk->with_offset(offset);
1510     }
1511   }
1512 
1513   // Flatten all Raw pointers together.
1514   if (tj->base() == Type::RawPtr)
1515     tj = TypeRawPtr::BOTTOM;
1516 
1517   if (tj->base() == Type::AnyPtr)
1518     tj = TypePtr::BOTTOM;      // An error, which the caller must check for.
1519 
1520   offset = tj->offset();
1521   assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
1522 
1523   assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
1524           (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
1525           (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
1526           (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
1527           (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1528           (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1529           (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr),
1530           "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
1531   assert( tj->ptr() != TypePtr::TopPTR &&
1532           tj->ptr() != TypePtr::AnyNull &&
1533           tj->ptr() != TypePtr::Null, "No imprecise addresses" );
1534 //    assert( tj->ptr() != TypePtr::Constant ||
1535 //            tj->base() == Type::RawPtr ||
1536 //            tj->base() == Type::KlassPtr, "No constant oop addresses" );
1537 
1538   return tj;
1539 }
1540 
1541 void Compile::AliasType::Init(int i, const TypePtr* at) {
1542   assert(AliasIdxTop <= i && i < Compile::current()->_max_alias_types, "Invalid alias index");
1543   _index = i;
1544   _adr_type = at;
1545   _field = nullptr;
1546   _element = nullptr;
1547   _is_rewritable = true; // default
1548   const TypeOopPtr *atoop = (at != nullptr) ? at->isa_oopptr() : nullptr;
1549   if (atoop != nullptr && atoop->is_known_instance()) {
1550     const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
1551     _general_index = Compile::current()->get_alias_index(gt);
1552   } else {
1553     _general_index = 0;
1554   }
1555 }
1556 
1557 BasicType Compile::AliasType::basic_type() const {
1558   if (element() != nullptr) {
1559     const Type* element = adr_type()->is_aryptr()->elem();
1560     return element->isa_narrowoop() ? T_OBJECT : element->array_element_basic_type();
1561   } if (field() != nullptr) {
1562     return field()->layout_type();
1563   } else {
1564     return T_ILLEGAL; // unknown
1565   }
1566 }
1567 
1568 //---------------------------------print_on------------------------------------
1569 #ifndef PRODUCT
1570 void Compile::AliasType::print_on(outputStream* st) {
1571   if (index() < 10)
1572         st->print("@ <%d> ", index());
1573   else  st->print("@ <%d>",  index());
1574   st->print(is_rewritable() ? "   " : " RO");
1575   int offset = adr_type()->offset();
1576   if (offset == Type::OffsetBot)
1577         st->print(" +any");
1578   else  st->print(" +%-3d", offset);
1579   st->print(" in ");
1580   adr_type()->dump_on(st);
1581   const TypeOopPtr* tjp = adr_type()->isa_oopptr();
1582   if (field() != nullptr && tjp) {
1583     if (tjp->is_instptr()->instance_klass()  != field()->holder() ||
1584         tjp->offset() != field()->offset_in_bytes()) {
1585       st->print(" != ");
1586       field()->print();
1587       st->print(" ***");
1588     }
1589   }
1590 }
1591 
1592 void print_alias_types() {
1593   Compile* C = Compile::current();
1594   tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
1595   for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
1596     C->alias_type(idx)->print_on(tty);
1597     tty->cr();
1598   }
1599 }
1600 #endif
1601 
1602 
1603 //----------------------------probe_alias_cache--------------------------------
1604 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
1605   intptr_t key = (intptr_t) adr_type;
1606   key ^= key >> logAliasCacheSize;
1607   return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
1608 }
1609 
1610 
1611 //-----------------------------grow_alias_types--------------------------------
1612 void Compile::grow_alias_types() {
1613   const int old_ats  = _max_alias_types; // how many before?
1614   const int new_ats  = old_ats;          // how many more?
1615   const int grow_ats = old_ats+new_ats;  // how many now?
1616   _max_alias_types = grow_ats;
1617   _alias_types =  REALLOC_ARENA_ARRAY(comp_arena(), AliasType*, _alias_types, old_ats, grow_ats);
1618   AliasType* ats =    NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
1619   Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
1620   for (int i = 0; i < new_ats; i++)  _alias_types[old_ats+i] = &ats[i];
1621 }
1622 
1623 
1624 //--------------------------------find_alias_type------------------------------
1625 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
1626   if (!do_aliasing()) {
1627     return alias_type(AliasIdxBot);
1628   }
1629 
1630   AliasCacheEntry* ace = probe_alias_cache(adr_type);
1631   if (ace->_adr_type == adr_type) {
1632     return alias_type(ace->_index);
1633   }
1634 
1635   // Handle special cases.
1636   if (adr_type == nullptr)          return alias_type(AliasIdxTop);
1637   if (adr_type == TypePtr::BOTTOM)  return alias_type(AliasIdxBot);
1638 
1639   // Do it the slow way.
1640   const TypePtr* flat = flatten_alias_type(adr_type);
1641 
1642 #ifdef ASSERT
1643   {
1644     ResourceMark rm;
1645     assert(flat == flatten_alias_type(flat), "not idempotent: adr_type = %s; flat = %s => %s",
1646            Type::str(adr_type), Type::str(flat), Type::str(flatten_alias_type(flat)));
1647     assert(flat != TypePtr::BOTTOM, "cannot alias-analyze an untyped ptr: adr_type = %s",
1648            Type::str(adr_type));
1649     if (flat->isa_oopptr() && !flat->isa_klassptr()) {
1650       const TypeOopPtr* foop = flat->is_oopptr();
1651       // Scalarizable allocations have exact klass always.
1652       bool exact = !foop->klass_is_exact() || foop->is_known_instance();
1653       const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
1654       assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type: foop = %s; xoop = %s",
1655              Type::str(foop), Type::str(xoop));
1656     }
1657   }
1658 #endif
1659 
1660   int idx = AliasIdxTop;
1661   for (int i = 0; i < num_alias_types(); i++) {
1662     if (alias_type(i)->adr_type() == flat) {
1663       idx = i;
1664       break;
1665     }
1666   }
1667 
1668   if (idx == AliasIdxTop) {
1669     if (no_create)  return nullptr;
1670     // Grow the array if necessary.
1671     if (_num_alias_types == _max_alias_types)  grow_alias_types();
1672     // Add a new alias type.
1673     idx = _num_alias_types++;
1674     _alias_types[idx]->Init(idx, flat);
1675     if (flat == TypeInstPtr::KLASS)  alias_type(idx)->set_rewritable(false);
1676     if (flat == TypeAryPtr::RANGE)   alias_type(idx)->set_rewritable(false);
1677     if (flat->isa_instptr()) {
1678       if (flat->offset() == java_lang_Class::klass_offset()
1679           && flat->is_instptr()->instance_klass() == env()->Class_klass())
1680         alias_type(idx)->set_rewritable(false);
1681     }
1682     if (flat->isa_aryptr()) {
1683 #ifdef ASSERT
1684       const int header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
1685       // (T_BYTE has the weakest alignment and size restrictions...)
1686       assert(flat->offset() < header_size_min, "array body reference must be OffsetBot");
1687 #endif
1688       if (flat->offset() == TypePtr::OffsetBot) {
1689         alias_type(idx)->set_element(flat->is_aryptr()->elem());
1690       }
1691     }
1692     if (flat->isa_klassptr()) {
1693       if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
1694         alias_type(idx)->set_rewritable(false);
1695       if (flat->offset() == in_bytes(Klass::modifier_flags_offset()))
1696         alias_type(idx)->set_rewritable(false);
1697       if (flat->offset() == in_bytes(Klass::access_flags_offset()))
1698         alias_type(idx)->set_rewritable(false);
1699       if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
1700         alias_type(idx)->set_rewritable(false);
1701       if (flat->offset() == in_bytes(Klass::secondary_super_cache_offset()))
1702         alias_type(idx)->set_rewritable(false);
1703     }
1704     // %%% (We would like to finalize JavaThread::threadObj_offset(),
1705     // but the base pointer type is not distinctive enough to identify
1706     // references into JavaThread.)
1707 
1708     // Check for final fields.
1709     const TypeInstPtr* tinst = flat->isa_instptr();
1710     if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
1711       ciField* field;
1712       if (tinst->const_oop() != nullptr &&
1713           tinst->instance_klass() == ciEnv::current()->Class_klass() &&
1714           tinst->offset() >= (tinst->instance_klass()->layout_helper_size_in_bytes())) {
1715         // static field
1716         ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
1717         field = k->get_field_by_offset(tinst->offset(), true);
1718       } else {
1719         ciInstanceKlass *k = tinst->instance_klass();
1720         field = k->get_field_by_offset(tinst->offset(), false);
1721       }
1722       assert(field == nullptr ||
1723              original_field == nullptr ||
1724              (field->holder() == original_field->holder() &&
1725               field->offset_in_bytes() == original_field->offset_in_bytes() &&
1726               field->is_static() == original_field->is_static()), "wrong field?");
1727       // Set field() and is_rewritable() attributes.
1728       if (field != nullptr)  alias_type(idx)->set_field(field);
1729     }
1730   }
1731 
1732   // Fill the cache for next time.
1733   ace->_adr_type = adr_type;
1734   ace->_index    = idx;
1735   assert(alias_type(adr_type) == alias_type(idx),  "type must be installed");
1736 
1737   // Might as well try to fill the cache for the flattened version, too.
1738   AliasCacheEntry* face = probe_alias_cache(flat);
1739   if (face->_adr_type == nullptr) {
1740     face->_adr_type = flat;
1741     face->_index    = idx;
1742     assert(alias_type(flat) == alias_type(idx), "flat type must work too");
1743   }
1744 
1745   return alias_type(idx);
1746 }
1747 
1748 
1749 Compile::AliasType* Compile::alias_type(ciField* field) {
1750   const TypeOopPtr* t;
1751   if (field->is_static())
1752     t = TypeInstPtr::make(field->holder()->java_mirror());
1753   else
1754     t = TypeOopPtr::make_from_klass_raw(field->holder());
1755   AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
1756   assert((field->is_final() || field->is_stable()) == !atp->is_rewritable(), "must get the rewritable bits correct");
1757   return atp;
1758 }
1759 
1760 
1761 //------------------------------have_alias_type--------------------------------
1762 bool Compile::have_alias_type(const TypePtr* adr_type) {
1763   AliasCacheEntry* ace = probe_alias_cache(adr_type);
1764   if (ace->_adr_type == adr_type) {
1765     return true;
1766   }
1767 
1768   // Handle special cases.
1769   if (adr_type == nullptr)             return true;
1770   if (adr_type == TypePtr::BOTTOM)  return true;
1771 
1772   return find_alias_type(adr_type, true, nullptr) != nullptr;
1773 }
1774 
1775 //-----------------------------must_alias--------------------------------------
1776 // True if all values of the given address type are in the given alias category.
1777 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
1778   if (alias_idx == AliasIdxBot)         return true;  // the universal category
1779   if (adr_type == nullptr)              return true;  // null serves as TypePtr::TOP
1780   if (alias_idx == AliasIdxTop)         return false; // the empty category
1781   if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
1782 
1783   // the only remaining possible overlap is identity
1784   int adr_idx = get_alias_index(adr_type);
1785   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1786   assert(adr_idx == alias_idx ||
1787          (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
1788           && adr_type                       != TypeOopPtr::BOTTOM),
1789          "should not be testing for overlap with an unsafe pointer");
1790   return adr_idx == alias_idx;
1791 }
1792 
1793 //------------------------------can_alias--------------------------------------
1794 // True if any values of the given address type are in the given alias category.
1795 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
1796   if (alias_idx == AliasIdxTop)         return false; // the empty category
1797   if (adr_type == nullptr)              return false; // null serves as TypePtr::TOP
1798   // Known instance doesn't alias with bottom memory
1799   if (alias_idx == AliasIdxBot)         return !adr_type->is_known_instance();                   // the universal category
1800   if (adr_type->base() == Type::AnyPtr) return !C->get_adr_type(alias_idx)->is_known_instance(); // TypePtr::BOTTOM or its twins
1801 
1802   // the only remaining possible overlap is identity
1803   int adr_idx = get_alias_index(adr_type);
1804   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1805   return adr_idx == alias_idx;
1806 }
1807 
1808 // Remove the opaque nodes that protect the Parse Predicates so that all unused
1809 // checks and uncommon_traps will be eliminated from the ideal graph.
1810 void Compile::cleanup_parse_predicates(PhaseIterGVN& igvn) const {
1811   if (parse_predicate_count() == 0) {
1812     return;
1813   }
1814   for (int i = parse_predicate_count(); i > 0; i--) {
1815     Node* n = parse_predicate_opaque1_node(i - 1);
1816     assert(n->Opcode() == Op_Opaque1, "must be");
1817     igvn.replace_node(n, n->in(1));
1818   }
1819   assert(parse_predicate_count() == 0, "should be clean!");
1820 }
1821 
1822 void Compile::record_for_post_loop_opts_igvn(Node* n) {
1823   if (!n->for_post_loop_opts_igvn()) {
1824     assert(!_for_post_loop_igvn.contains(n), "duplicate");
1825     n->add_flag(Node::NodeFlags::Flag_for_post_loop_opts_igvn);
1826     _for_post_loop_igvn.append(n);
1827   }
1828 }
1829 
1830 void Compile::remove_from_post_loop_opts_igvn(Node* n) {
1831   n->remove_flag(Node::NodeFlags::Flag_for_post_loop_opts_igvn);
1832   _for_post_loop_igvn.remove(n);
1833 }
1834 
1835 void Compile::process_for_post_loop_opts_igvn(PhaseIterGVN& igvn) {
1836   // Verify that all previous optimizations produced a valid graph
1837   // at least to this point, even if no loop optimizations were done.
1838   PhaseIdealLoop::verify(igvn);
1839 
1840   C->set_post_loop_opts_phase(); // no more loop opts allowed
1841 
1842   assert(!C->major_progress(), "not cleared");
1843 
1844   if (_for_post_loop_igvn.length() > 0) {
1845     while (_for_post_loop_igvn.length() > 0) {
1846       Node* n = _for_post_loop_igvn.pop();
1847       n->remove_flag(Node::NodeFlags::Flag_for_post_loop_opts_igvn);
1848       igvn._worklist.push(n);
1849     }
1850     igvn.optimize();
1851     assert(_for_post_loop_igvn.length() == 0, "no more delayed nodes allowed");
1852 
1853     // Sometimes IGVN sets major progress (e.g., when processing loop nodes).
1854     if (C->major_progress()) {
1855       C->clear_major_progress(); // ensure that major progress is now clear
1856     }
1857   }
1858 }
1859 
1860 void Compile::record_unstable_if_trap(UnstableIfTrap* trap) {
1861   if (OptimizeUnstableIf) {
1862     _unstable_if_traps.append(trap);
1863   }
1864 }
1865 
1866 void Compile::remove_useless_unstable_if_traps(Unique_Node_List& useful) {
1867   for (int i = _unstable_if_traps.length() - 1; i >= 0; i--) {
1868     UnstableIfTrap* trap = _unstable_if_traps.at(i);
1869     Node* n = trap->uncommon_trap();
1870     if (!useful.member(n)) {
1871       _unstable_if_traps.delete_at(i); // replaces i-th with last element which is known to be useful (already processed)
1872     }
1873   }
1874 }
1875 
1876 // Remove the unstable if trap associated with 'unc' from candidates. It is either dead
1877 // or fold-compares case. Return true if succeed or not found.
1878 //
1879 // In rare cases, the found trap has been processed. It is too late to delete it. Return
1880 // false and ask fold-compares to yield.
1881 //
1882 // 'fold-compares' may use the uncommon_trap of the dominating IfNode to cover the fused
1883 // IfNode. This breaks the unstable_if trap invariant: control takes the unstable path
1884 // when deoptimization does happen.
1885 bool Compile::remove_unstable_if_trap(CallStaticJavaNode* unc, bool yield) {
1886   for (int i = 0; i < _unstable_if_traps.length(); ++i) {
1887     UnstableIfTrap* trap = _unstable_if_traps.at(i);
1888     if (trap->uncommon_trap() == unc) {
1889       if (yield && trap->modified()) {
1890         return false;
1891       }
1892       _unstable_if_traps.delete_at(i);
1893       break;
1894     }
1895   }
1896   return true;
1897 }
1898 
1899 // Re-calculate unstable_if traps with the liveness of next_bci, which points to the unlikely path.
1900 // It needs to be done after igvn because fold-compares may fuse uncommon_traps and before renumbering.
1901 void Compile::process_for_unstable_if_traps(PhaseIterGVN& igvn) {
1902   for (int i = _unstable_if_traps.length() - 1; i >= 0; --i) {
1903     UnstableIfTrap* trap = _unstable_if_traps.at(i);
1904     CallStaticJavaNode* unc = trap->uncommon_trap();
1905     int next_bci = trap->next_bci();
1906     bool modified = trap->modified();
1907 
1908     if (next_bci != -1 && !modified) {
1909       assert(!_dead_node_list.test(unc->_idx), "changing a dead node!");
1910       JVMState* jvms = unc->jvms();
1911       ciMethod* method = jvms->method();
1912       ciBytecodeStream iter(method);
1913 
1914       iter.force_bci(jvms->bci());
1915       assert(next_bci == iter.next_bci() || next_bci == iter.get_dest(), "wrong next_bci at unstable_if");
1916       Bytecodes::Code c = iter.cur_bc();
1917       Node* lhs = nullptr;
1918       Node* rhs = nullptr;
1919       if (c == Bytecodes::_if_acmpeq || c == Bytecodes::_if_acmpne) {
1920         lhs = unc->peek_operand(0);
1921         rhs = unc->peek_operand(1);
1922       } else if (c == Bytecodes::_ifnull || c == Bytecodes::_ifnonnull) {
1923         lhs = unc->peek_operand(0);
1924       }
1925 
1926       ResourceMark rm;
1927       const MethodLivenessResult& live_locals = method->liveness_at_bci(next_bci);
1928       assert(live_locals.is_valid(), "broken liveness info");
1929       int len = (int)live_locals.size();
1930 
1931       for (int i = 0; i < len; i++) {
1932         Node* local = unc->local(jvms, i);
1933         // kill local using the liveness of next_bci.
1934         // give up when the local looks like an operand to secure reexecution.
1935         if (!live_locals.at(i) && !local->is_top() && local != lhs && local!= rhs) {
1936           uint idx = jvms->locoff() + i;
1937 #ifdef ASSERT
1938           if (PrintOpto && Verbose) {
1939             tty->print("[unstable_if] kill local#%d: ", idx);
1940             local->dump();
1941             tty->cr();
1942           }
1943 #endif
1944           igvn.replace_input_of(unc, idx, top());
1945           modified = true;
1946         }
1947       }
1948     }
1949 
1950     // keep the mondified trap for late query
1951     if (modified) {
1952       trap->set_modified();
1953     } else {
1954       _unstable_if_traps.delete_at(i);
1955     }
1956   }
1957   igvn.optimize();
1958 }
1959 
1960 // StringOpts and late inlining of string methods
1961 void Compile::inline_string_calls(bool parse_time) {
1962   {
1963     // remove useless nodes to make the usage analysis simpler
1964     ResourceMark rm;
1965     PhaseRemoveUseless pru(initial_gvn(), *igvn_worklist());
1966   }
1967 
1968   {
1969     ResourceMark rm;
1970     print_method(PHASE_BEFORE_STRINGOPTS, 3);
1971     PhaseStringOpts pso(initial_gvn());
1972     print_method(PHASE_AFTER_STRINGOPTS, 3);
1973   }
1974 
1975   // now inline anything that we skipped the first time around
1976   if (!parse_time) {
1977     _late_inlines_pos = _late_inlines.length();
1978   }
1979 
1980   while (_string_late_inlines.length() > 0) {
1981     CallGenerator* cg = _string_late_inlines.pop();
1982     cg->do_late_inline();
1983     if (failing())  return;
1984   }
1985   _string_late_inlines.trunc_to(0);
1986 }
1987 
1988 // Late inlining of boxing methods
1989 void Compile::inline_boxing_calls(PhaseIterGVN& igvn) {
1990   if (_boxing_late_inlines.length() > 0) {
1991     assert(has_boxed_value(), "inconsistent");
1992 
1993     PhaseGVN* gvn = initial_gvn();
1994     set_inlining_incrementally(true);
1995 
1996     igvn_worklist()->ensure_empty(); // should be done with igvn
1997 
1998     _late_inlines_pos = _late_inlines.length();
1999 
2000     while (_boxing_late_inlines.length() > 0) {
2001       CallGenerator* cg = _boxing_late_inlines.pop();
2002       cg->do_late_inline();
2003       if (failing())  return;
2004     }
2005     _boxing_late_inlines.trunc_to(0);
2006 
2007     inline_incrementally_cleanup(igvn);
2008 
2009     set_inlining_incrementally(false);
2010   }
2011 }
2012 
2013 bool Compile::inline_incrementally_one() {
2014   assert(IncrementalInline, "incremental inlining should be on");
2015 
2016   TracePhase tp("incrementalInline_inline", &timers[_t_incrInline_inline]);
2017 
2018   set_inlining_progress(false);
2019   set_do_cleanup(false);
2020 
2021   for (int i = 0; i < _late_inlines.length(); i++) {
2022     _late_inlines_pos = i+1;
2023     CallGenerator* cg = _late_inlines.at(i);
2024     bool does_dispatch = cg->is_virtual_late_inline() || cg->is_mh_late_inline();
2025     if (inlining_incrementally() || does_dispatch) { // a call can be either inlined or strength-reduced to a direct call
2026       cg->do_late_inline();
2027       assert(_late_inlines.at(i) == cg, "no insertions before current position allowed");
2028       if (failing()) {
2029         return false;
2030       } else if (inlining_progress()) {
2031         _late_inlines_pos = i+1; // restore the position in case new elements were inserted
2032         print_method(PHASE_INCREMENTAL_INLINE_STEP, 3, cg->call_node());
2033         break; // process one call site at a time
2034       }
2035     } else {
2036       // Ignore late inline direct calls when inlining is not allowed.
2037       // They are left in the late inline list when node budget is exhausted until the list is fully drained.
2038     }
2039   }
2040   // Remove processed elements.
2041   _late_inlines.remove_till(_late_inlines_pos);
2042   _late_inlines_pos = 0;
2043 
2044   assert(inlining_progress() || _late_inlines.length() == 0, "no progress");
2045 
2046   bool needs_cleanup = do_cleanup() || over_inlining_cutoff();
2047 
2048   set_inlining_progress(false);
2049   set_do_cleanup(false);
2050 
2051   bool force_cleanup = directive()->IncrementalInlineForceCleanupOption;
2052   return (_late_inlines.length() > 0) && !needs_cleanup && !force_cleanup;
2053 }
2054 
2055 void Compile::inline_incrementally_cleanup(PhaseIterGVN& igvn) {
2056   {
2057     TracePhase tp("incrementalInline_pru", &timers[_t_incrInline_pru]);
2058     ResourceMark rm;
2059     PhaseRemoveUseless pru(initial_gvn(), *igvn_worklist());
2060   }
2061   {
2062     TracePhase tp("incrementalInline_igvn", &timers[_t_incrInline_igvn]);
2063     igvn.reset_from_gvn(initial_gvn());
2064     igvn.optimize();
2065   }
2066   print_method(PHASE_INCREMENTAL_INLINE_CLEANUP, 3);
2067 }
2068 
2069 // Perform incremental inlining until bound on number of live nodes is reached
2070 void Compile::inline_incrementally(PhaseIterGVN& igvn) {
2071   TracePhase tp("incrementalInline", &timers[_t_incrInline]);
2072 
2073   set_inlining_incrementally(true);
2074   uint low_live_nodes = 0;
2075 
2076   while (_late_inlines.length() > 0) {
2077     if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2078       if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
2079         TracePhase tp("incrementalInline_ideal", &timers[_t_incrInline_ideal]);
2080         // PhaseIdealLoop is expensive so we only try it once we are
2081         // out of live nodes and we only try it again if the previous
2082         // helped got the number of nodes down significantly
2083         PhaseIdealLoop::optimize(igvn, LoopOptsNone);
2084         if (failing())  return;
2085         low_live_nodes = live_nodes();
2086         _major_progress = true;
2087       }
2088 
2089       if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2090         bool do_print_inlining = print_inlining() || print_intrinsics();
2091         if (do_print_inlining || log() != nullptr) {
2092           // Print inlining message for candidates that we couldn't inline for lack of space.
2093           for (int i = 0; i < _late_inlines.length(); i++) {
2094             CallGenerator* cg = _late_inlines.at(i);
2095             const char* msg = "live nodes > LiveNodeCountInliningCutoff";
2096             if (do_print_inlining) {
2097               cg->print_inlining_late(msg);
2098             }
2099             log_late_inline_failure(cg, msg);
2100           }
2101         }
2102         break; // finish
2103       }
2104     }
2105 
2106     igvn_worklist()->ensure_empty(); // should be done with igvn
2107 
2108     while (inline_incrementally_one()) {
2109       assert(!failing(), "inconsistent");
2110     }
2111     if (failing())  return;
2112 
2113     inline_incrementally_cleanup(igvn);
2114 
2115     print_method(PHASE_INCREMENTAL_INLINE_STEP, 3);
2116 
2117     if (failing())  return;
2118 
2119     if (_late_inlines.length() == 0) {
2120       break; // no more progress
2121     }
2122   }
2123 
2124   igvn_worklist()->ensure_empty(); // should be done with igvn
2125 
2126   if (_string_late_inlines.length() > 0) {
2127     assert(has_stringbuilder(), "inconsistent");
2128 
2129     inline_string_calls(false);
2130 
2131     if (failing())  return;
2132 
2133     inline_incrementally_cleanup(igvn);
2134   }
2135 
2136   set_inlining_incrementally(false);
2137 }
2138 
2139 void Compile::process_late_inline_calls_no_inline(PhaseIterGVN& igvn) {
2140   // "inlining_incrementally() == false" is used to signal that no inlining is allowed
2141   // (see LateInlineVirtualCallGenerator::do_late_inline_check() for details).
2142   // Tracking and verification of modified nodes is disabled by setting "_modified_nodes == nullptr"
2143   // as if "inlining_incrementally() == true" were set.
2144   assert(inlining_incrementally() == false, "not allowed");
2145   assert(_modified_nodes == nullptr, "not allowed");
2146   assert(_late_inlines.length() > 0, "sanity");
2147 
2148   while (_late_inlines.length() > 0) {
2149     igvn_worklist()->ensure_empty(); // should be done with igvn
2150 
2151     while (inline_incrementally_one()) {
2152       assert(!failing(), "inconsistent");
2153     }
2154     if (failing())  return;
2155 
2156     inline_incrementally_cleanup(igvn);
2157   }
2158 }
2159 
2160 bool Compile::optimize_loops(PhaseIterGVN& igvn, LoopOptsMode mode) {
2161   if (_loop_opts_cnt > 0) {
2162     while (major_progress() && (_loop_opts_cnt > 0)) {
2163       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2164       PhaseIdealLoop::optimize(igvn, mode);
2165       _loop_opts_cnt--;
2166       if (failing())  return false;
2167       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
2168     }
2169   }
2170   return true;
2171 }
2172 
2173 // Remove edges from "root" to each SafePoint at a backward branch.
2174 // They were inserted during parsing (see add_safepoint()) to make
2175 // infinite loops without calls or exceptions visible to root, i.e.,
2176 // useful.
2177 void Compile::remove_root_to_sfpts_edges(PhaseIterGVN& igvn) {
2178   Node *r = root();
2179   if (r != nullptr) {
2180     for (uint i = r->req(); i < r->len(); ++i) {
2181       Node *n = r->in(i);
2182       if (n != nullptr && n->is_SafePoint()) {
2183         r->rm_prec(i);
2184         if (n->outcnt() == 0) {
2185           igvn.remove_dead_node(n);
2186         }
2187         --i;
2188       }
2189     }
2190     // Parsing may have added top inputs to the root node (Path
2191     // leading to the Halt node proven dead). Make sure we get a
2192     // chance to clean them up.
2193     igvn._worklist.push(r);
2194     igvn.optimize();
2195   }
2196 }
2197 
2198 //------------------------------Optimize---------------------------------------
2199 // Given a graph, optimize it.
2200 void Compile::Optimize() {
2201   TracePhase tp("optimizer", &timers[_t_optimizer]);
2202 
2203 #ifndef PRODUCT
2204   if (env()->break_at_compile()) {
2205     BREAKPOINT;
2206   }
2207 
2208 #endif
2209 
2210   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
2211 #ifdef ASSERT
2212   bs->verify_gc_barriers(this, BarrierSetC2::BeforeOptimize);
2213 #endif
2214 
2215   ResourceMark rm;
2216 
2217   print_inlining_reinit();
2218 
2219   NOT_PRODUCT( verify_graph_edges(); )
2220 
2221   print_method(PHASE_AFTER_PARSING, 1);
2222 
2223  {
2224   // Iterative Global Value Numbering, including ideal transforms
2225   // Initialize IterGVN with types and values from parse-time GVN
2226   PhaseIterGVN igvn(initial_gvn());
2227 #ifdef ASSERT
2228   _modified_nodes = new (comp_arena()) Unique_Node_List(comp_arena());
2229 #endif
2230   {
2231     TracePhase tp("iterGVN", &timers[_t_iterGVN]);
2232     igvn.optimize();
2233   }
2234 
2235   if (failing())  return;
2236 
2237   print_method(PHASE_ITER_GVN1, 2);
2238 
2239   process_for_unstable_if_traps(igvn);
2240 
2241   if (failing())  return;
2242 
2243   inline_incrementally(igvn);
2244 
2245   print_method(PHASE_INCREMENTAL_INLINE, 2);
2246 
2247   if (failing())  return;
2248 
2249   if (eliminate_boxing()) {
2250     // Inline valueOf() methods now.
2251     inline_boxing_calls(igvn);
2252 
2253     if (failing())  return;
2254 
2255     if (AlwaysIncrementalInline || StressIncrementalInlining) {
2256       inline_incrementally(igvn);
2257     }
2258 
2259     print_method(PHASE_INCREMENTAL_BOXING_INLINE, 2);
2260 
2261     if (failing())  return;
2262   }
2263 
2264   // Remove the speculative part of types and clean up the graph from
2265   // the extra CastPP nodes whose only purpose is to carry them. Do
2266   // that early so that optimizations are not disrupted by the extra
2267   // CastPP nodes.
2268   remove_speculative_types(igvn);
2269 
2270   if (failing())  return;
2271 
2272   // No more new expensive nodes will be added to the list from here
2273   // so keep only the actual candidates for optimizations.
2274   cleanup_expensive_nodes(igvn);
2275 
2276   if (failing())  return;
2277 
2278   assert(EnableVectorSupport || !has_vbox_nodes(), "sanity");
2279   if (EnableVectorSupport && has_vbox_nodes()) {
2280     TracePhase tp("", &timers[_t_vector]);
2281     PhaseVector pv(igvn);
2282     pv.optimize_vector_boxes();
2283     if (failing())  return;
2284     print_method(PHASE_ITER_GVN_AFTER_VECTOR, 2);
2285   }
2286   assert(!has_vbox_nodes(), "sanity");
2287 
2288   if (!failing() && RenumberLiveNodes && live_nodes() + NodeLimitFudgeFactor < unique()) {
2289     Compile::TracePhase tp("", &timers[_t_renumberLive]);
2290     igvn_worklist()->ensure_empty(); // should be done with igvn
2291     {
2292       ResourceMark rm;
2293       PhaseRenumberLive prl(initial_gvn(), *igvn_worklist());
2294     }
2295     igvn.reset_from_gvn(initial_gvn());
2296     igvn.optimize();
2297   }
2298 
2299   // Now that all inlining is over and no PhaseRemoveUseless will run, cut edge from root to loop
2300   // safepoints
2301   remove_root_to_sfpts_edges(igvn);
2302 
2303   if (failing())  return;
2304 
2305   // Perform escape analysis
2306   if (do_escape_analysis() && ConnectionGraph::has_candidates(this)) {
2307     if (has_loops()) {
2308       // Cleanup graph (remove dead nodes).
2309       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2310       PhaseIdealLoop::optimize(igvn, LoopOptsMaxUnroll);
2311       if (major_progress()) print_method(PHASE_PHASEIDEAL_BEFORE_EA, 2);
2312       if (failing())  return;
2313     }
2314     bool progress;
2315     do {
2316       ConnectionGraph::do_analysis(this, &igvn);
2317 
2318       if (failing())  return;
2319 
2320       int mcount = macro_count(); // Record number of allocations and locks before IGVN
2321 
2322       // Optimize out fields loads from scalar replaceable allocations.
2323       igvn.optimize();
2324       print_method(PHASE_ITER_GVN_AFTER_EA, 2);
2325 
2326       if (failing())  return;
2327 
2328       if (congraph() != nullptr && macro_count() > 0) {
2329         TracePhase tp("macroEliminate", &timers[_t_macroEliminate]);
2330         PhaseMacroExpand mexp(igvn);
2331         mexp.eliminate_macro_nodes();
2332         igvn.set_delay_transform(false);
2333 
2334         igvn.optimize();
2335         print_method(PHASE_ITER_GVN_AFTER_ELIMINATION, 2);
2336 
2337         if (failing())  return;
2338       }
2339       progress = do_iterative_escape_analysis() &&
2340                  (macro_count() < mcount) &&
2341                  ConnectionGraph::has_candidates(this);
2342       // Try again if candidates exist and made progress
2343       // by removing some allocations and/or locks.
2344     } while (progress);
2345   }
2346 
2347   // Loop transforms on the ideal graph.  Range Check Elimination,
2348   // peeling, unrolling, etc.
2349 
2350   // Set loop opts counter
2351   if((_loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
2352     {
2353       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2354       PhaseIdealLoop::optimize(igvn, LoopOptsDefault);
2355       _loop_opts_cnt--;
2356       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP1, 2);
2357       if (failing())  return;
2358     }
2359     // Loop opts pass if partial peeling occurred in previous pass
2360     if(PartialPeelLoop && major_progress() && (_loop_opts_cnt > 0)) {
2361       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2362       PhaseIdealLoop::optimize(igvn, LoopOptsSkipSplitIf);
2363       _loop_opts_cnt--;
2364       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP2, 2);
2365       if (failing())  return;
2366     }
2367     // Loop opts pass for loop-unrolling before CCP
2368     if(major_progress() && (_loop_opts_cnt > 0)) {
2369       TracePhase tp("idealLoop", &timers[_t_idealLoop]);
2370       PhaseIdealLoop::optimize(igvn, LoopOptsSkipSplitIf);
2371       _loop_opts_cnt--;
2372       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP3, 2);
2373     }
2374     if (!failing()) {
2375       // Verify that last round of loop opts produced a valid graph
2376       PhaseIdealLoop::verify(igvn);
2377     }
2378   }
2379   if (failing())  return;
2380 
2381   // Conditional Constant Propagation;
2382   PhaseCCP ccp( &igvn );
2383   assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
2384   {
2385     TracePhase tp("ccp", &timers[_t_ccp]);
2386     ccp.do_transform();
2387   }
2388   print_method(PHASE_CCP1, 2);
2389 
2390   assert( true, "Break here to ccp.dump_old2new_map()");
2391 
2392   // Iterative Global Value Numbering, including ideal transforms
2393   {
2394     TracePhase tp("iterGVN2", &timers[_t_iterGVN2]);
2395     igvn.reset_from_igvn(&ccp);
2396     igvn.optimize();
2397   }
2398   print_method(PHASE_ITER_GVN2, 2);
2399 
2400   if (failing())  return;
2401 
2402   // Loop transforms on the ideal graph.  Range Check Elimination,
2403   // peeling, unrolling, etc.
2404   if (!optimize_loops(igvn, LoopOptsDefault)) {
2405     return;
2406   }
2407 
2408   if (failing())  return;
2409 
2410   C->clear_major_progress(); // ensure that major progress is now clear
2411 
2412   process_for_post_loop_opts_igvn(igvn);
2413 
2414   if (failing())  return;
2415 
2416 #ifdef ASSERT
2417   bs->verify_gc_barriers(this, BarrierSetC2::BeforeMacroExpand);
2418 #endif
2419 
2420   {
2421     TracePhase tp("macroExpand", &timers[_t_macroExpand]);
2422     PhaseMacroExpand  mex(igvn);
2423     if (mex.expand_macro_nodes()) {
2424       assert(failing(), "must bail out w/ explicit message");
2425       return;
2426     }
2427     print_method(PHASE_MACRO_EXPANSION, 2);
2428   }
2429 
2430   {
2431     TracePhase tp("barrierExpand", &timers[_t_barrierExpand]);
2432     if (bs->expand_barriers(this, igvn)) {
2433       assert(failing(), "must bail out w/ explicit message");
2434       return;
2435     }
2436     print_method(PHASE_BARRIER_EXPANSION, 2);
2437   }
2438 
2439   if (C->max_vector_size() > 0) {
2440     C->optimize_logic_cones(igvn);
2441     igvn.optimize();
2442   }
2443 
2444   DEBUG_ONLY( _modified_nodes = nullptr; )
2445 
2446   assert(igvn._worklist.size() == 0, "not empty");
2447 
2448   assert(_late_inlines.length() == 0 || IncrementalInlineMH || IncrementalInlineVirtual, "not empty");
2449 
2450   if (_late_inlines.length() > 0) {
2451     // More opportunities to optimize virtual and MH calls.
2452     // Though it's maybe too late to perform inlining, strength-reducing them to direct calls is still an option.
2453     process_late_inline_calls_no_inline(igvn);
2454     if (failing())  return;
2455   }
2456  } // (End scope of igvn; run destructor if necessary for asserts.)
2457 
2458  check_no_dead_use();
2459 
2460  process_print_inlining();
2461 
2462  // We will never use the NodeHash table any more. Clear it so that final_graph_reshaping does not have
2463  // to remove hashes to unlock nodes for modifications.
2464  C->node_hash()->clear();
2465 
2466  // A method with only infinite loops has no edges entering loops from root
2467  {
2468    TracePhase tp("graphReshape", &timers[_t_graphReshaping]);
2469    if (final_graph_reshaping()) {
2470      assert(failing(), "must bail out w/ explicit message");
2471      return;
2472    }
2473  }
2474 
2475  print_method(PHASE_OPTIMIZE_FINISHED, 2);
2476  DEBUG_ONLY(set_phase_optimize_finished();)
2477 }
2478 
2479 #ifdef ASSERT
2480 void Compile::check_no_dead_use() const {
2481   ResourceMark rm;
2482   Unique_Node_List wq;
2483   wq.push(root());
2484   for (uint i = 0; i < wq.size(); ++i) {
2485     Node* n = wq.at(i);
2486     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
2487       Node* u = n->fast_out(j);
2488       if (u->outcnt() == 0 && !u->is_Con()) {
2489         u->dump();
2490         fatal("no reachable node should have no use");
2491       }
2492       wq.push(u);
2493     }
2494   }
2495 }
2496 #endif
2497 
2498 void Compile::inline_vector_reboxing_calls() {
2499   if (C->_vector_reboxing_late_inlines.length() > 0) {
2500     _late_inlines_pos = C->_late_inlines.length();
2501     while (_vector_reboxing_late_inlines.length() > 0) {
2502       CallGenerator* cg = _vector_reboxing_late_inlines.pop();
2503       cg->do_late_inline();
2504       if (failing())  return;
2505       print_method(PHASE_INLINE_VECTOR_REBOX, 3, cg->call_node());
2506     }
2507     _vector_reboxing_late_inlines.trunc_to(0);
2508   }
2509 }
2510 
2511 bool Compile::has_vbox_nodes() {
2512   if (C->_vector_reboxing_late_inlines.length() > 0) {
2513     return true;
2514   }
2515   for (int macro_idx = C->macro_count() - 1; macro_idx >= 0; macro_idx--) {
2516     Node * n = C->macro_node(macro_idx);
2517     assert(n->is_macro(), "only macro nodes expected here");
2518     if (n->Opcode() == Op_VectorUnbox || n->Opcode() == Op_VectorBox || n->Opcode() == Op_VectorBoxAllocate) {
2519       return true;
2520     }
2521   }
2522   return false;
2523 }
2524 
2525 //---------------------------- Bitwise operation packing optimization ---------------------------
2526 
2527 static bool is_vector_unary_bitwise_op(Node* n) {
2528   return n->Opcode() == Op_XorV &&
2529          VectorNode::is_vector_bitwise_not_pattern(n);
2530 }
2531 
2532 static bool is_vector_binary_bitwise_op(Node* n) {
2533   switch (n->Opcode()) {
2534     case Op_AndV:
2535     case Op_OrV:
2536       return true;
2537 
2538     case Op_XorV:
2539       return !is_vector_unary_bitwise_op(n);
2540 
2541     default:
2542       return false;
2543   }
2544 }
2545 
2546 static bool is_vector_ternary_bitwise_op(Node* n) {
2547   return n->Opcode() == Op_MacroLogicV;
2548 }
2549 
2550 static bool is_vector_bitwise_op(Node* n) {
2551   return is_vector_unary_bitwise_op(n)  ||
2552          is_vector_binary_bitwise_op(n) ||
2553          is_vector_ternary_bitwise_op(n);
2554 }
2555 
2556 static bool is_vector_bitwise_cone_root(Node* n) {
2557   if (n->bottom_type()->isa_vectmask() || !is_vector_bitwise_op(n)) {
2558     return false;
2559   }
2560   for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2561     if (is_vector_bitwise_op(n->fast_out(i))) {
2562       return false;
2563     }
2564   }
2565   return true;
2566 }
2567 
2568 static uint collect_unique_inputs(Node* n, Unique_Node_List& inputs) {
2569   uint cnt = 0;
2570   if (is_vector_bitwise_op(n)) {
2571     uint inp_cnt = n->is_predicated_vector() ? n->req()-1 : n->req();
2572     if (VectorNode::is_vector_bitwise_not_pattern(n)) {
2573       for (uint i = 1; i < inp_cnt; i++) {
2574         Node* in = n->in(i);
2575         bool skip = VectorNode::is_all_ones_vector(in);
2576         if (!skip && !inputs.member(in)) {
2577           inputs.push(in);
2578           cnt++;
2579         }
2580       }
2581       assert(cnt <= 1, "not unary");
2582     } else {
2583       uint last_req = inp_cnt;
2584       if (is_vector_ternary_bitwise_op(n)) {
2585         last_req = inp_cnt - 1; // skip last input
2586       }
2587       for (uint i = 1; i < last_req; i++) {
2588         Node* def = n->in(i);
2589         if (!inputs.member(def)) {
2590           inputs.push(def);
2591           cnt++;
2592         }
2593       }
2594     }
2595   } else { // not a bitwise operations
2596     if (!inputs.member(n)) {
2597       inputs.push(n);
2598       cnt++;
2599     }
2600   }
2601   return cnt;
2602 }
2603 
2604 void Compile::collect_logic_cone_roots(Unique_Node_List& list) {
2605   Unique_Node_List useful_nodes;
2606   C->identify_useful_nodes(useful_nodes);
2607 
2608   for (uint i = 0; i < useful_nodes.size(); i++) {
2609     Node* n = useful_nodes.at(i);
2610     if (is_vector_bitwise_cone_root(n)) {
2611       list.push(n);
2612     }
2613   }
2614 }
2615 
2616 Node* Compile::xform_to_MacroLogicV(PhaseIterGVN& igvn,
2617                                     const TypeVect* vt,
2618                                     Unique_Node_List& partition,
2619                                     Unique_Node_List& inputs) {
2620   assert(partition.size() == 2 || partition.size() == 3, "not supported");
2621   assert(inputs.size()    == 2 || inputs.size()    == 3, "not supported");
2622   assert(Matcher::match_rule_supported_vector(Op_MacroLogicV, vt->length(), vt->element_basic_type()), "not supported");
2623 
2624   Node* in1 = inputs.at(0);
2625   Node* in2 = inputs.at(1);
2626   Node* in3 = (inputs.size() == 3 ? inputs.at(2) : in2);
2627 
2628   uint func = compute_truth_table(partition, inputs);
2629 
2630   Node* pn = partition.at(partition.size() - 1);
2631   Node* mask = pn->is_predicated_vector() ? pn->in(pn->req()-1) : nullptr;
2632   return igvn.transform(MacroLogicVNode::make(igvn, in1, in2, in3, mask, func, vt));
2633 }
2634 
2635 static uint extract_bit(uint func, uint pos) {
2636   return (func & (1 << pos)) >> pos;
2637 }
2638 
2639 //
2640 //  A macro logic node represents a truth table. It has 4 inputs,
2641 //  First three inputs corresponds to 3 columns of a truth table
2642 //  and fourth input captures the logic function.
2643 //
2644 //  eg.  fn = (in1 AND in2) OR in3;
2645 //
2646 //      MacroNode(in1,in2,in3,fn)
2647 //
2648 //  -----------------
2649 //  in1 in2 in3  fn
2650 //  -----------------
2651 //  0    0   0    0
2652 //  0    0   1    1
2653 //  0    1   0    0
2654 //  0    1   1    1
2655 //  1    0   0    0
2656 //  1    0   1    1
2657 //  1    1   0    1
2658 //  1    1   1    1
2659 //
2660 
2661 uint Compile::eval_macro_logic_op(uint func, uint in1 , uint in2, uint in3) {
2662   int res = 0;
2663   for (int i = 0; i < 8; i++) {
2664     int bit1 = extract_bit(in1, i);
2665     int bit2 = extract_bit(in2, i);
2666     int bit3 = extract_bit(in3, i);
2667 
2668     int func_bit_pos = (bit1 << 2 | bit2 << 1 | bit3);
2669     int func_bit = extract_bit(func, func_bit_pos);
2670 
2671     res |= func_bit << i;
2672   }
2673   return res;
2674 }
2675 
2676 static uint eval_operand(Node* n, ResourceHashtable<Node*,uint>& eval_map) {
2677   assert(n != nullptr, "");
2678   assert(eval_map.contains(n), "absent");
2679   return *(eval_map.get(n));
2680 }
2681 
2682 static void eval_operands(Node* n,
2683                           uint& func1, uint& func2, uint& func3,
2684                           ResourceHashtable<Node*,uint>& eval_map) {
2685   assert(is_vector_bitwise_op(n), "");
2686 
2687   if (is_vector_unary_bitwise_op(n)) {
2688     Node* opnd = n->in(1);
2689     if (VectorNode::is_vector_bitwise_not_pattern(n) && VectorNode::is_all_ones_vector(opnd)) {
2690       opnd = n->in(2);
2691     }
2692     func1 = eval_operand(opnd, eval_map);
2693   } else if (is_vector_binary_bitwise_op(n)) {
2694     func1 = eval_operand(n->in(1), eval_map);
2695     func2 = eval_operand(n->in(2), eval_map);
2696   } else {
2697     assert(is_vector_ternary_bitwise_op(n), "unknown operation");
2698     func1 = eval_operand(n->in(1), eval_map);
2699     func2 = eval_operand(n->in(2), eval_map);
2700     func3 = eval_operand(n->in(3), eval_map);
2701   }
2702 }
2703 
2704 uint Compile::compute_truth_table(Unique_Node_List& partition, Unique_Node_List& inputs) {
2705   assert(inputs.size() <= 3, "sanity");
2706   ResourceMark rm;
2707   uint res = 0;
2708   ResourceHashtable<Node*,uint> eval_map;
2709 
2710   // Populate precomputed functions for inputs.
2711   // Each input corresponds to one column of 3 input truth-table.
2712   uint input_funcs[] = { 0xAA,   // (_, _, c) -> c
2713                          0xCC,   // (_, b, _) -> b
2714                          0xF0 }; // (a, _, _) -> a
2715   for (uint i = 0; i < inputs.size(); i++) {
2716     eval_map.put(inputs.at(i), input_funcs[2-i]);
2717   }
2718 
2719   for (uint i = 0; i < partition.size(); i++) {
2720     Node* n = partition.at(i);
2721 
2722     uint func1 = 0, func2 = 0, func3 = 0;
2723     eval_operands(n, func1, func2, func3, eval_map);
2724 
2725     switch (n->Opcode()) {
2726       case Op_OrV:
2727         assert(func3 == 0, "not binary");
2728         res = func1 | func2;
2729         break;
2730       case Op_AndV:
2731         assert(func3 == 0, "not binary");
2732         res = func1 & func2;
2733         break;
2734       case Op_XorV:
2735         if (VectorNode::is_vector_bitwise_not_pattern(n)) {
2736           assert(func2 == 0 && func3 == 0, "not unary");
2737           res = (~func1) & 0xFF;
2738         } else {
2739           assert(func3 == 0, "not binary");
2740           res = func1 ^ func2;
2741         }
2742         break;
2743       case Op_MacroLogicV:
2744         // Ordering of inputs may change during evaluation of sub-tree
2745         // containing MacroLogic node as a child node, thus a re-evaluation
2746         // makes sure that function is evaluated in context of current
2747         // inputs.
2748         res = eval_macro_logic_op(n->in(4)->get_int(), func1, func2, func3);
2749         break;
2750 
2751       default: assert(false, "not supported: %s", n->Name());
2752     }
2753     assert(res <= 0xFF, "invalid");
2754     eval_map.put(n, res);
2755   }
2756   return res;
2757 }
2758 
2759 // Criteria under which nodes gets packed into a macro logic node:-
2760 //  1) Parent and both child nodes are all unmasked or masked with
2761 //     same predicates.
2762 //  2) Masked parent can be packed with left child if it is predicated
2763 //     and both have same predicates.
2764 //  3) Masked parent can be packed with right child if its un-predicated
2765 //     or has matching predication condition.
2766 //  4) An unmasked parent can be packed with an unmasked child.
2767 bool Compile::compute_logic_cone(Node* n, Unique_Node_List& partition, Unique_Node_List& inputs) {
2768   assert(partition.size() == 0, "not empty");
2769   assert(inputs.size() == 0, "not empty");
2770   if (is_vector_ternary_bitwise_op(n)) {
2771     return false;
2772   }
2773 
2774   bool is_unary_op = is_vector_unary_bitwise_op(n);
2775   if (is_unary_op) {
2776     assert(collect_unique_inputs(n, inputs) == 1, "not unary");
2777     return false; // too few inputs
2778   }
2779 
2780   bool pack_left_child = true;
2781   bool pack_right_child = true;
2782 
2783   bool left_child_LOP = is_vector_bitwise_op(n->in(1));
2784   bool right_child_LOP = is_vector_bitwise_op(n->in(2));
2785 
2786   int left_child_input_cnt = 0;
2787   int right_child_input_cnt = 0;
2788 
2789   bool parent_is_predicated = n->is_predicated_vector();
2790   bool left_child_predicated = n->in(1)->is_predicated_vector();
2791   bool right_child_predicated = n->in(2)->is_predicated_vector();
2792 
2793   Node* parent_pred = parent_is_predicated ? n->in(n->req()-1) : nullptr;
2794   Node* left_child_pred = left_child_predicated ? n->in(1)->in(n->in(1)->req()-1) : nullptr;
2795   Node* right_child_pred = right_child_predicated ? n->in(1)->in(n->in(1)->req()-1) : nullptr;
2796 
2797   do {
2798     if (pack_left_child && left_child_LOP &&
2799         ((!parent_is_predicated && !left_child_predicated) ||
2800         ((parent_is_predicated && left_child_predicated &&
2801           parent_pred == left_child_pred)))) {
2802        partition.push(n->in(1));
2803        left_child_input_cnt = collect_unique_inputs(n->in(1), inputs);
2804     } else {
2805        inputs.push(n->in(1));
2806        left_child_input_cnt = 1;
2807     }
2808 
2809     if (pack_right_child && right_child_LOP &&
2810         (!right_child_predicated ||
2811          (right_child_predicated && parent_is_predicated &&
2812           parent_pred == right_child_pred))) {
2813        partition.push(n->in(2));
2814        right_child_input_cnt = collect_unique_inputs(n->in(2), inputs);
2815     } else {
2816        inputs.push(n->in(2));
2817        right_child_input_cnt = 1;
2818     }
2819 
2820     if (inputs.size() > 3) {
2821       assert(partition.size() > 0, "");
2822       inputs.clear();
2823       partition.clear();
2824       if (left_child_input_cnt > right_child_input_cnt) {
2825         pack_left_child = false;
2826       } else {
2827         pack_right_child = false;
2828       }
2829     } else {
2830       break;
2831     }
2832   } while(true);
2833 
2834   if(partition.size()) {
2835     partition.push(n);
2836   }
2837 
2838   return (partition.size() == 2 || partition.size() == 3) &&
2839          (inputs.size()    == 2 || inputs.size()    == 3);
2840 }
2841 
2842 void Compile::process_logic_cone_root(PhaseIterGVN &igvn, Node *n, VectorSet &visited) {
2843   assert(is_vector_bitwise_op(n), "not a root");
2844 
2845   visited.set(n->_idx);
2846 
2847   // 1) Do a DFS walk over the logic cone.
2848   for (uint i = 1; i < n->req(); i++) {
2849     Node* in = n->in(i);
2850     if (!visited.test(in->_idx) && is_vector_bitwise_op(in)) {
2851       process_logic_cone_root(igvn, in, visited);
2852     }
2853   }
2854 
2855   // 2) Bottom up traversal: Merge node[s] with
2856   // the parent to form macro logic node.
2857   Unique_Node_List partition;
2858   Unique_Node_List inputs;
2859   if (compute_logic_cone(n, partition, inputs)) {
2860     const TypeVect* vt = n->bottom_type()->is_vect();
2861     Node* pn = partition.at(partition.size() - 1);
2862     Node* mask = pn->is_predicated_vector() ? pn->in(pn->req()-1) : nullptr;
2863     if (mask == nullptr ||
2864         Matcher::match_rule_supported_vector_masked(Op_MacroLogicV, vt->length(), vt->element_basic_type())) {
2865       Node* macro_logic = xform_to_MacroLogicV(igvn, vt, partition, inputs);
2866       VectorNode::trace_new_vector(macro_logic, "MacroLogic");
2867       igvn.replace_node(n, macro_logic);
2868     }
2869   }
2870 }
2871 
2872 void Compile::optimize_logic_cones(PhaseIterGVN &igvn) {
2873   ResourceMark rm;
2874   if (Matcher::match_rule_supported(Op_MacroLogicV)) {
2875     Unique_Node_List list;
2876     collect_logic_cone_roots(list);
2877 
2878     while (list.size() > 0) {
2879       Node* n = list.pop();
2880       const TypeVect* vt = n->bottom_type()->is_vect();
2881       bool supported = Matcher::match_rule_supported_vector(Op_MacroLogicV, vt->length(), vt->element_basic_type());
2882       if (supported) {
2883         VectorSet visited(comp_arena());
2884         process_logic_cone_root(igvn, n, visited);
2885       }
2886     }
2887   }
2888 }
2889 
2890 //------------------------------Code_Gen---------------------------------------
2891 // Given a graph, generate code for it
2892 void Compile::Code_Gen() {
2893   if (failing()) {
2894     return;
2895   }
2896 
2897   // Perform instruction selection.  You might think we could reclaim Matcher
2898   // memory PDQ, but actually the Matcher is used in generating spill code.
2899   // Internals of the Matcher (including some VectorSets) must remain live
2900   // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
2901   // set a bit in reclaimed memory.
2902 
2903   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2904   // nodes.  Mapping is only valid at the root of each matched subtree.
2905   NOT_PRODUCT( verify_graph_edges(); )
2906 
2907   Matcher matcher;
2908   _matcher = &matcher;
2909   {
2910     TracePhase tp("matcher", &timers[_t_matcher]);
2911     matcher.match();
2912     if (failing()) {
2913       return;
2914     }
2915   }
2916   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
2917   // nodes.  Mapping is only valid at the root of each matched subtree.
2918   NOT_PRODUCT( verify_graph_edges(); )
2919 
2920   // If you have too many nodes, or if matching has failed, bail out
2921   check_node_count(0, "out of nodes matching instructions");
2922   if (failing()) {
2923     return;
2924   }
2925 
2926   print_method(PHASE_MATCHING, 2);
2927 
2928   // Build a proper-looking CFG
2929   PhaseCFG cfg(node_arena(), root(), matcher);
2930   _cfg = &cfg;
2931   {
2932     TracePhase tp("scheduler", &timers[_t_scheduler]);
2933     bool success = cfg.do_global_code_motion();
2934     if (!success) {
2935       return;
2936     }
2937 
2938     print_method(PHASE_GLOBAL_CODE_MOTION, 2);
2939     NOT_PRODUCT( verify_graph_edges(); )
2940     cfg.verify();
2941   }
2942 
2943   PhaseChaitin regalloc(unique(), cfg, matcher, false);
2944   _regalloc = &regalloc;
2945   {
2946     TracePhase tp("regalloc", &timers[_t_registerAllocation]);
2947     // Perform register allocation.  After Chaitin, use-def chains are
2948     // no longer accurate (at spill code) and so must be ignored.
2949     // Node->LRG->reg mappings are still accurate.
2950     _regalloc->Register_Allocate();
2951 
2952     // Bail out if the allocator builds too many nodes
2953     if (failing()) {
2954       return;
2955     }
2956   }
2957 
2958   // Prior to register allocation we kept empty basic blocks in case the
2959   // the allocator needed a place to spill.  After register allocation we
2960   // are not adding any new instructions.  If any basic block is empty, we
2961   // can now safely remove it.
2962   {
2963     TracePhase tp("blockOrdering", &timers[_t_blockOrdering]);
2964     cfg.remove_empty_blocks();
2965     if (do_freq_based_layout()) {
2966       PhaseBlockLayout layout(cfg);
2967     } else {
2968       cfg.set_loop_alignment();
2969     }
2970     cfg.fixup_flow();
2971     cfg.remove_unreachable_blocks();
2972     cfg.verify_dominator_tree();
2973   }
2974 
2975   // Apply peephole optimizations
2976   if( OptoPeephole ) {
2977     TracePhase tp("peephole", &timers[_t_peephole]);
2978     PhasePeephole peep( _regalloc, cfg);
2979     peep.do_transform();
2980   }
2981 
2982   // Do late expand if CPU requires this.
2983   if (Matcher::require_postalloc_expand) {
2984     TracePhase tp("postalloc_expand", &timers[_t_postalloc_expand]);
2985     cfg.postalloc_expand(_regalloc);
2986   }
2987 
2988   // Convert Nodes to instruction bits in a buffer
2989   {
2990     TracePhase tp("output", &timers[_t_output]);
2991     PhaseOutput output;
2992     output.Output();
2993     if (failing())  return;
2994     output.install();
2995   }
2996 
2997   print_method(PHASE_FINAL_CODE, 1);
2998 
2999   // He's dead, Jim.
3000   _cfg     = (PhaseCFG*)((intptr_t)0xdeadbeef);
3001   _regalloc = (PhaseChaitin*)((intptr_t)0xdeadbeef);
3002 }
3003 
3004 //------------------------------Final_Reshape_Counts---------------------------
3005 // This class defines counters to help identify when a method
3006 // may/must be executed using hardware with only 24-bit precision.
3007 struct Final_Reshape_Counts : public StackObj {
3008   int  _call_count;             // count non-inlined 'common' calls
3009   int  _float_count;            // count float ops requiring 24-bit precision
3010   int  _double_count;           // count double ops requiring more precision
3011   int  _java_call_count;        // count non-inlined 'java' calls
3012   int  _inner_loop_count;       // count loops which need alignment
3013   VectorSet _visited;           // Visitation flags
3014   Node_List _tests;             // Set of IfNodes & PCTableNodes
3015 
3016   Final_Reshape_Counts() :
3017     _call_count(0), _float_count(0), _double_count(0),
3018     _java_call_count(0), _inner_loop_count(0) { }
3019 
3020   void inc_call_count  () { _call_count  ++; }
3021   void inc_float_count () { _float_count ++; }
3022   void inc_double_count() { _double_count++; }
3023   void inc_java_call_count() { _java_call_count++; }
3024   void inc_inner_loop_count() { _inner_loop_count++; }
3025 
3026   int  get_call_count  () const { return _call_count  ; }
3027   int  get_float_count () const { return _float_count ; }
3028   int  get_double_count() const { return _double_count; }
3029   int  get_java_call_count() const { return _java_call_count; }
3030   int  get_inner_loop_count() const { return _inner_loop_count; }
3031 };
3032 
3033 // Eliminate trivially redundant StoreCMs and accumulate their
3034 // precedence edges.
3035 void Compile::eliminate_redundant_card_marks(Node* n) {
3036   assert(n->Opcode() == Op_StoreCM, "expected StoreCM");
3037   if (n->in(MemNode::Address)->outcnt() > 1) {
3038     // There are multiple users of the same address so it might be
3039     // possible to eliminate some of the StoreCMs
3040     Node* mem = n->in(MemNode::Memory);
3041     Node* adr = n->in(MemNode::Address);
3042     Node* val = n->in(MemNode::ValueIn);
3043     Node* prev = n;
3044     bool done = false;
3045     // Walk the chain of StoreCMs eliminating ones that match.  As
3046     // long as it's a chain of single users then the optimization is
3047     // safe.  Eliminating partially redundant StoreCMs would require
3048     // cloning copies down the other paths.
3049     while (mem->Opcode() == Op_StoreCM && mem->outcnt() == 1 && !done) {
3050       if (adr == mem->in(MemNode::Address) &&
3051           val == mem->in(MemNode::ValueIn)) {
3052         // redundant StoreCM
3053         if (mem->req() > MemNode::OopStore) {
3054           // Hasn't been processed by this code yet.
3055           n->add_prec(mem->in(MemNode::OopStore));
3056         } else {
3057           // Already converted to precedence edge
3058           for (uint i = mem->req(); i < mem->len(); i++) {
3059             // Accumulate any precedence edges
3060             if (mem->in(i) != nullptr) {
3061               n->add_prec(mem->in(i));
3062             }
3063           }
3064           // Everything above this point has been processed.
3065           done = true;
3066         }
3067         // Eliminate the previous StoreCM
3068         prev->set_req(MemNode::Memory, mem->in(MemNode::Memory));
3069         assert(mem->outcnt() == 0, "should be dead");
3070         mem->disconnect_inputs(this);
3071       } else {
3072         prev = mem;
3073       }
3074       mem = prev->in(MemNode::Memory);
3075     }
3076   }
3077 }
3078 
3079 //------------------------------final_graph_reshaping_impl----------------------
3080 // Implement items 1-5 from final_graph_reshaping below.
3081 void Compile::final_graph_reshaping_impl(Node *n, Final_Reshape_Counts& frc, Unique_Node_List& dead_nodes) {
3082 
3083   if ( n->outcnt() == 0 ) return; // dead node
3084   uint nop = n->Opcode();
3085 
3086   // Check for 2-input instruction with "last use" on right input.
3087   // Swap to left input.  Implements item (2).
3088   if( n->req() == 3 &&          // two-input instruction
3089       n->in(1)->outcnt() > 1 && // left use is NOT a last use
3090       (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
3091       n->in(2)->outcnt() == 1 &&// right use IS a last use
3092       !n->in(2)->is_Con() ) {   // right use is not a constant
3093     // Check for commutative opcode
3094     switch( nop ) {
3095     case Op_AddI:  case Op_AddF:  case Op_AddD:  case Op_AddL:
3096     case Op_MaxI:  case Op_MaxL:  case Op_MaxF:  case Op_MaxD:
3097     case Op_MinI:  case Op_MinL:  case Op_MinF:  case Op_MinD:
3098     case Op_MulI:  case Op_MulF:  case Op_MulD:  case Op_MulL:
3099     case Op_AndL:  case Op_XorL:  case Op_OrL:
3100     case Op_AndI:  case Op_XorI:  case Op_OrI: {
3101       // Move "last use" input to left by swapping inputs
3102       n->swap_edges(1, 2);
3103       break;
3104     }
3105     default:
3106       break;
3107     }
3108   }
3109 
3110 #ifdef ASSERT
3111   if( n->is_Mem() ) {
3112     int alias_idx = get_alias_index(n->as_Mem()->adr_type());
3113     assert( n->in(0) != nullptr || alias_idx != Compile::AliasIdxRaw ||
3114             // oop will be recorded in oop map if load crosses safepoint
3115             n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
3116                              LoadNode::is_immutable_value(n->in(MemNode::Address))),
3117             "raw memory operations should have control edge");
3118   }
3119   if (n->is_MemBar()) {
3120     MemBarNode* mb = n->as_MemBar();
3121     if (mb->trailing_store() || mb->trailing_load_store()) {
3122       assert(mb->leading_membar()->trailing_membar() == mb, "bad membar pair");
3123       Node* mem = BarrierSet::barrier_set()->barrier_set_c2()->step_over_gc_barrier(mb->in(MemBarNode::Precedent));
3124       assert((mb->trailing_store() && mem->is_Store() && mem->as_Store()->is_release()) ||
3125              (mb->trailing_load_store() && mem->is_LoadStore()), "missing mem op");
3126     } else if (mb->leading()) {
3127       assert(mb->trailing_membar()->leading_membar() == mb, "bad membar pair");
3128     }
3129   }
3130 #endif
3131   // Count FPU ops and common calls, implements item (3)
3132   bool gc_handled = BarrierSet::barrier_set()->barrier_set_c2()->final_graph_reshaping(this, n, nop, dead_nodes);
3133   if (!gc_handled) {
3134     final_graph_reshaping_main_switch(n, frc, nop, dead_nodes);
3135   }
3136 
3137   // Collect CFG split points
3138   if (n->is_MultiBranch() && !n->is_RangeCheck()) {
3139     frc._tests.push(n);
3140   }
3141 }
3142 
3143 void Compile::final_graph_reshaping_main_switch(Node* n, Final_Reshape_Counts& frc, uint nop, Unique_Node_List& dead_nodes) {
3144   switch( nop ) {
3145   // Count all float operations that may use FPU
3146   case Op_AddF:
3147   case Op_SubF:
3148   case Op_MulF:
3149   case Op_DivF:
3150   case Op_NegF:
3151   case Op_ModF:
3152   case Op_ConvI2F:
3153   case Op_ConF:
3154   case Op_CmpF:
3155   case Op_CmpF3:
3156   case Op_StoreF:
3157   case Op_LoadF:
3158   // case Op_ConvL2F: // longs are split into 32-bit halves
3159     frc.inc_float_count();
3160     break;
3161 
3162   case Op_ConvF2D:
3163   case Op_ConvD2F:
3164     frc.inc_float_count();
3165     frc.inc_double_count();
3166     break;
3167 
3168   // Count all double operations that may use FPU
3169   case Op_AddD:
3170   case Op_SubD:
3171   case Op_MulD:
3172   case Op_DivD:
3173   case Op_NegD:
3174   case Op_ModD:
3175   case Op_ConvI2D:
3176   case Op_ConvD2I:
3177   // case Op_ConvL2D: // handled by leaf call
3178   // case Op_ConvD2L: // handled by leaf call
3179   case Op_ConD:
3180   case Op_CmpD:
3181   case Op_CmpD3:
3182   case Op_StoreD:
3183   case Op_LoadD:
3184   case Op_LoadD_unaligned:
3185     frc.inc_double_count();
3186     break;
3187   case Op_Opaque1:              // Remove Opaque Nodes before matching
3188   case Op_Opaque3:
3189     n->subsume_by(n->in(1), this);
3190     break;
3191   case Op_CallStaticJava:
3192   case Op_CallJava:
3193   case Op_CallDynamicJava:
3194     frc.inc_java_call_count(); // Count java call site;
3195   case Op_CallRuntime:
3196   case Op_CallLeaf:
3197   case Op_CallLeafVector:
3198   case Op_CallLeafNoFP: {
3199     assert (n->is_Call(), "");
3200     CallNode *call = n->as_Call();
3201     // Count call sites where the FP mode bit would have to be flipped.
3202     // Do not count uncommon runtime calls:
3203     // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
3204     // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
3205     if (!call->is_CallStaticJava() || !call->as_CallStaticJava()->_name) {
3206       frc.inc_call_count();   // Count the call site
3207     } else {                  // See if uncommon argument is shared
3208       Node *n = call->in(TypeFunc::Parms);
3209       int nop = n->Opcode();
3210       // Clone shared simple arguments to uncommon calls, item (1).
3211       if (n->outcnt() > 1 &&
3212           !n->is_Proj() &&
3213           nop != Op_CreateEx &&
3214           nop != Op_CheckCastPP &&
3215           nop != Op_DecodeN &&
3216           nop != Op_DecodeNKlass &&
3217           !n->is_Mem() &&
3218           !n->is_Phi()) {
3219         Node *x = n->clone();
3220         call->set_req(TypeFunc::Parms, x);
3221       }
3222     }
3223     break;
3224   }
3225 
3226   case Op_StoreCM:
3227     {
3228       // Convert OopStore dependence into precedence edge
3229       Node* prec = n->in(MemNode::OopStore);
3230       n->del_req(MemNode::OopStore);
3231       n->add_prec(prec);
3232       eliminate_redundant_card_marks(n);
3233     }
3234 
3235     // fall through
3236 
3237   case Op_StoreB:
3238   case Op_StoreC:
3239   case Op_StoreI:
3240   case Op_StoreL:
3241   case Op_CompareAndSwapB:
3242   case Op_CompareAndSwapS:
3243   case Op_CompareAndSwapI:
3244   case Op_CompareAndSwapL:
3245   case Op_CompareAndSwapP:
3246   case Op_CompareAndSwapN:
3247   case Op_WeakCompareAndSwapB:
3248   case Op_WeakCompareAndSwapS:
3249   case Op_WeakCompareAndSwapI:
3250   case Op_WeakCompareAndSwapL:
3251   case Op_WeakCompareAndSwapP:
3252   case Op_WeakCompareAndSwapN:
3253   case Op_CompareAndExchangeB:
3254   case Op_CompareAndExchangeS:
3255   case Op_CompareAndExchangeI:
3256   case Op_CompareAndExchangeL:
3257   case Op_CompareAndExchangeP:
3258   case Op_CompareAndExchangeN:
3259   case Op_GetAndAddS:
3260   case Op_GetAndAddB:
3261   case Op_GetAndAddI:
3262   case Op_GetAndAddL:
3263   case Op_GetAndSetS:
3264   case Op_GetAndSetB:
3265   case Op_GetAndSetI:
3266   case Op_GetAndSetL:
3267   case Op_GetAndSetP:
3268   case Op_GetAndSetN:
3269   case Op_StoreP:
3270   case Op_StoreN:
3271   case Op_StoreNKlass:
3272   case Op_LoadB:
3273   case Op_LoadUB:
3274   case Op_LoadUS:
3275   case Op_LoadI:
3276   case Op_LoadKlass:
3277   case Op_LoadNKlass:
3278   case Op_LoadL:
3279   case Op_LoadL_unaligned:
3280   case Op_LoadP:
3281   case Op_LoadN:
3282   case Op_LoadRange:
3283   case Op_LoadS:
3284     break;
3285 
3286   case Op_AddP: {               // Assert sane base pointers
3287     Node *addp = n->in(AddPNode::Address);
3288     assert( !addp->is_AddP() ||
3289             addp->in(AddPNode::Base)->is_top() || // Top OK for allocation
3290             addp->in(AddPNode::Base) == n->in(AddPNode::Base),
3291             "Base pointers must match (addp %u)", addp->_idx );
3292 #ifdef _LP64
3293     if ((UseCompressedOops || UseCompressedClassPointers) &&
3294         addp->Opcode() == Op_ConP &&
3295         addp == n->in(AddPNode::Base) &&
3296         n->in(AddPNode::Offset)->is_Con()) {
3297       // If the transformation of ConP to ConN+DecodeN is beneficial depends
3298       // on the platform and on the compressed oops mode.
3299       // Use addressing with narrow klass to load with offset on x86.
3300       // Some platforms can use the constant pool to load ConP.
3301       // Do this transformation here since IGVN will convert ConN back to ConP.
3302       const Type* t = addp->bottom_type();
3303       bool is_oop   = t->isa_oopptr() != nullptr;
3304       bool is_klass = t->isa_klassptr() != nullptr;
3305 
3306       if ((is_oop   && Matcher::const_oop_prefer_decode()  ) ||
3307           (is_klass && Matcher::const_klass_prefer_decode())) {
3308         Node* nn = nullptr;
3309 
3310         int op = is_oop ? Op_ConN : Op_ConNKlass;
3311 
3312         // Look for existing ConN node of the same exact type.
3313         Node* r  = root();
3314         uint cnt = r->outcnt();
3315         for (uint i = 0; i < cnt; i++) {
3316           Node* m = r->raw_out(i);
3317           if (m!= nullptr && m->Opcode() == op &&
3318               m->bottom_type()->make_ptr() == t) {
3319             nn = m;
3320             break;
3321           }
3322         }
3323         if (nn != nullptr) {
3324           // Decode a narrow oop to match address
3325           // [R12 + narrow_oop_reg<<3 + offset]
3326           if (is_oop) {
3327             nn = new DecodeNNode(nn, t);
3328           } else {
3329             nn = new DecodeNKlassNode(nn, t);
3330           }
3331           // Check for succeeding AddP which uses the same Base.
3332           // Otherwise we will run into the assertion above when visiting that guy.
3333           for (uint i = 0; i < n->outcnt(); ++i) {
3334             Node *out_i = n->raw_out(i);
3335             if (out_i && out_i->is_AddP() && out_i->in(AddPNode::Base) == addp) {
3336               out_i->set_req(AddPNode::Base, nn);
3337 #ifdef ASSERT
3338               for (uint j = 0; j < out_i->outcnt(); ++j) {
3339                 Node *out_j = out_i->raw_out(j);
3340                 assert(out_j == nullptr || !out_j->is_AddP() || out_j->in(AddPNode::Base) != addp,
3341                        "more than 2 AddP nodes in a chain (out_j %u)", out_j->_idx);
3342               }
3343 #endif
3344             }
3345           }
3346           n->set_req(AddPNode::Base, nn);
3347           n->set_req(AddPNode::Address, nn);
3348           if (addp->outcnt() == 0) {
3349             addp->disconnect_inputs(this);
3350           }
3351         }
3352       }
3353     }
3354 #endif
3355     break;
3356   }
3357 
3358   case Op_CastPP: {
3359     // Remove CastPP nodes to gain more freedom during scheduling but
3360     // keep the dependency they encode as control or precedence edges
3361     // (if control is set already) on memory operations. Some CastPP
3362     // nodes don't have a control (don't carry a dependency): skip
3363     // those.
3364     if (n->in(0) != nullptr) {
3365       ResourceMark rm;
3366       Unique_Node_List wq;
3367       wq.push(n);
3368       for (uint next = 0; next < wq.size(); ++next) {
3369         Node *m = wq.at(next);
3370         for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
3371           Node* use = m->fast_out(i);
3372           if (use->is_Mem() || use->is_EncodeNarrowPtr()) {
3373             use->ensure_control_or_add_prec(n->in(0));
3374           } else {
3375             switch(use->Opcode()) {
3376             case Op_AddP:
3377             case Op_DecodeN:
3378             case Op_DecodeNKlass:
3379             case Op_CheckCastPP:
3380             case Op_CastPP:
3381               wq.push(use);
3382               break;
3383             }
3384           }
3385         }
3386       }
3387     }
3388     const bool is_LP64 = LP64_ONLY(true) NOT_LP64(false);
3389     if (is_LP64 && n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
3390       Node* in1 = n->in(1);
3391       const Type* t = n->bottom_type();
3392       Node* new_in1 = in1->clone();
3393       new_in1->as_DecodeN()->set_type(t);
3394 
3395       if (!Matcher::narrow_oop_use_complex_address()) {
3396         //
3397         // x86, ARM and friends can handle 2 adds in addressing mode
3398         // and Matcher can fold a DecodeN node into address by using
3399         // a narrow oop directly and do implicit null check in address:
3400         //
3401         // [R12 + narrow_oop_reg<<3 + offset]
3402         // NullCheck narrow_oop_reg
3403         //
3404         // On other platforms (Sparc) we have to keep new DecodeN node and
3405         // use it to do implicit null check in address:
3406         //
3407         // decode_not_null narrow_oop_reg, base_reg
3408         // [base_reg + offset]
3409         // NullCheck base_reg
3410         //
3411         // Pin the new DecodeN node to non-null path on these platform (Sparc)
3412         // to keep the information to which null check the new DecodeN node
3413         // corresponds to use it as value in implicit_null_check().
3414         //
3415         new_in1->set_req(0, n->in(0));
3416       }
3417 
3418       n->subsume_by(new_in1, this);
3419       if (in1->outcnt() == 0) {
3420         in1->disconnect_inputs(this);
3421       }
3422     } else {
3423       n->subsume_by(n->in(1), this);
3424       if (n->outcnt() == 0) {
3425         n->disconnect_inputs(this);
3426       }
3427     }
3428     break;
3429   }
3430 #ifdef _LP64
3431   case Op_CmpP:
3432     // Do this transformation here to preserve CmpPNode::sub() and
3433     // other TypePtr related Ideal optimizations (for example, ptr nullness).
3434     if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
3435       Node* in1 = n->in(1);
3436       Node* in2 = n->in(2);
3437       if (!in1->is_DecodeNarrowPtr()) {
3438         in2 = in1;
3439         in1 = n->in(2);
3440       }
3441       assert(in1->is_DecodeNarrowPtr(), "sanity");
3442 
3443       Node* new_in2 = nullptr;
3444       if (in2->is_DecodeNarrowPtr()) {
3445         assert(in2->Opcode() == in1->Opcode(), "must be same node type");
3446         new_in2 = in2->in(1);
3447       } else if (in2->Opcode() == Op_ConP) {
3448         const Type* t = in2->bottom_type();
3449         if (t == TypePtr::NULL_PTR) {
3450           assert(in1->is_DecodeN(), "compare klass to null?");
3451           // Don't convert CmpP null check into CmpN if compressed
3452           // oops implicit null check is not generated.
3453           // This will allow to generate normal oop implicit null check.
3454           if (Matcher::gen_narrow_oop_implicit_null_checks())
3455             new_in2 = ConNode::make(TypeNarrowOop::NULL_PTR);
3456           //
3457           // This transformation together with CastPP transformation above
3458           // will generated code for implicit null checks for compressed oops.
3459           //
3460           // The original code after Optimize()
3461           //
3462           //    LoadN memory, narrow_oop_reg
3463           //    decode narrow_oop_reg, base_reg
3464           //    CmpP base_reg, nullptr
3465           //    CastPP base_reg // NotNull
3466           //    Load [base_reg + offset], val_reg
3467           //
3468           // after these transformations will be
3469           //
3470           //    LoadN memory, narrow_oop_reg
3471           //    CmpN narrow_oop_reg, nullptr
3472           //    decode_not_null narrow_oop_reg, base_reg
3473           //    Load [base_reg + offset], val_reg
3474           //
3475           // and the uncommon path (== nullptr) will use narrow_oop_reg directly
3476           // since narrow oops can be used in debug info now (see the code in
3477           // final_graph_reshaping_walk()).
3478           //
3479           // At the end the code will be matched to
3480           // on x86:
3481           //
3482           //    Load_narrow_oop memory, narrow_oop_reg
3483           //    Load [R12 + narrow_oop_reg<<3 + offset], val_reg
3484           //    NullCheck narrow_oop_reg
3485           //
3486           // and on sparc:
3487           //
3488           //    Load_narrow_oop memory, narrow_oop_reg
3489           //    decode_not_null narrow_oop_reg, base_reg
3490           //    Load [base_reg + offset], val_reg
3491           //    NullCheck base_reg
3492           //
3493         } else if (t->isa_oopptr()) {
3494           new_in2 = ConNode::make(t->make_narrowoop());
3495         } else if (t->isa_klassptr()) {
3496           new_in2 = ConNode::make(t->make_narrowklass());
3497         }
3498       }
3499       if (new_in2 != nullptr) {
3500         Node* cmpN = new CmpNNode(in1->in(1), new_in2);
3501         n->subsume_by(cmpN, this);
3502         if (in1->outcnt() == 0) {
3503           in1->disconnect_inputs(this);
3504         }
3505         if (in2->outcnt() == 0) {
3506           in2->disconnect_inputs(this);
3507         }
3508       }
3509     }
3510     break;
3511 
3512   case Op_DecodeN:
3513   case Op_DecodeNKlass:
3514     assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
3515     // DecodeN could be pinned when it can't be fold into
3516     // an address expression, see the code for Op_CastPP above.
3517     assert(n->in(0) == nullptr || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
3518     break;
3519 
3520   case Op_EncodeP:
3521   case Op_EncodePKlass: {
3522     Node* in1 = n->in(1);
3523     if (in1->is_DecodeNarrowPtr()) {
3524       n->subsume_by(in1->in(1), this);
3525     } else if (in1->Opcode() == Op_ConP) {
3526       const Type* t = in1->bottom_type();
3527       if (t == TypePtr::NULL_PTR) {
3528         assert(t->isa_oopptr(), "null klass?");
3529         n->subsume_by(ConNode::make(TypeNarrowOop::NULL_PTR), this);
3530       } else if (t->isa_oopptr()) {
3531         n->subsume_by(ConNode::make(t->make_narrowoop()), this);
3532       } else if (t->isa_klassptr()) {
3533         n->subsume_by(ConNode::make(t->make_narrowklass()), this);
3534       }
3535     }
3536     if (in1->outcnt() == 0) {
3537       in1->disconnect_inputs(this);
3538     }
3539     break;
3540   }
3541 
3542   case Op_Proj: {
3543     if (OptimizeStringConcat || IncrementalInline) {
3544       ProjNode* proj = n->as_Proj();
3545       if (proj->_is_io_use) {
3546         assert(proj->_con == TypeFunc::I_O || proj->_con == TypeFunc::Memory, "");
3547         // Separate projections were used for the exception path which
3548         // are normally removed by a late inline.  If it wasn't inlined
3549         // then they will hang around and should just be replaced with
3550         // the original one. Merge them.
3551         Node* non_io_proj = proj->in(0)->as_Multi()->proj_out_or_null(proj->_con, false /*is_io_use*/);
3552         if (non_io_proj  != nullptr) {
3553           proj->subsume_by(non_io_proj , this);
3554         }
3555       }
3556     }
3557     break;
3558   }
3559 
3560   case Op_Phi:
3561     if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
3562       // The EncodeP optimization may create Phi with the same edges
3563       // for all paths. It is not handled well by Register Allocator.
3564       Node* unique_in = n->in(1);
3565       assert(unique_in != nullptr, "");
3566       uint cnt = n->req();
3567       for (uint i = 2; i < cnt; i++) {
3568         Node* m = n->in(i);
3569         assert(m != nullptr, "");
3570         if (unique_in != m)
3571           unique_in = nullptr;
3572       }
3573       if (unique_in != nullptr) {
3574         n->subsume_by(unique_in, this);
3575       }
3576     }
3577     break;
3578 
3579 #endif
3580 
3581 #ifdef ASSERT
3582   case Op_CastII:
3583     // Verify that all range check dependent CastII nodes were removed.
3584     if (n->isa_CastII()->has_range_check()) {
3585       n->dump(3);
3586       assert(false, "Range check dependent CastII node was not removed");
3587     }
3588     break;
3589 #endif
3590 
3591   case Op_ModI:
3592     if (UseDivMod) {
3593       // Check if a%b and a/b both exist
3594       Node* d = n->find_similar(Op_DivI);
3595       if (d) {
3596         // Replace them with a fused divmod if supported
3597         if (Matcher::has_match_rule(Op_DivModI)) {
3598           DivModINode* divmod = DivModINode::make(n);
3599           d->subsume_by(divmod->div_proj(), this);
3600           n->subsume_by(divmod->mod_proj(), this);
3601         } else {
3602           // replace a%b with a-((a/b)*b)
3603           Node* mult = new MulINode(d, d->in(2));
3604           Node* sub  = new SubINode(d->in(1), mult);
3605           n->subsume_by(sub, this);
3606         }
3607       }
3608     }
3609     break;
3610 
3611   case Op_ModL:
3612     if (UseDivMod) {
3613       // Check if a%b and a/b both exist
3614       Node* d = n->find_similar(Op_DivL);
3615       if (d) {
3616         // Replace them with a fused divmod if supported
3617         if (Matcher::has_match_rule(Op_DivModL)) {
3618           DivModLNode* divmod = DivModLNode::make(n);
3619           d->subsume_by(divmod->div_proj(), this);
3620           n->subsume_by(divmod->mod_proj(), this);
3621         } else {
3622           // replace a%b with a-((a/b)*b)
3623           Node* mult = new MulLNode(d, d->in(2));
3624           Node* sub  = new SubLNode(d->in(1), mult);
3625           n->subsume_by(sub, this);
3626         }
3627       }
3628     }
3629     break;
3630 
3631   case Op_UModI:
3632     if (UseDivMod) {
3633       // Check if a%b and a/b both exist
3634       Node* d = n->find_similar(Op_UDivI);
3635       if (d) {
3636         // Replace them with a fused unsigned divmod if supported
3637         if (Matcher::has_match_rule(Op_UDivModI)) {
3638           UDivModINode* divmod = UDivModINode::make(n);
3639           d->subsume_by(divmod->div_proj(), this);
3640           n->subsume_by(divmod->mod_proj(), this);
3641         } else {
3642           // replace a%b with a-((a/b)*b)
3643           Node* mult = new MulINode(d, d->in(2));
3644           Node* sub  = new SubINode(d->in(1), mult);
3645           n->subsume_by(sub, this);
3646         }
3647       }
3648     }
3649     break;
3650 
3651   case Op_UModL:
3652     if (UseDivMod) {
3653       // Check if a%b and a/b both exist
3654       Node* d = n->find_similar(Op_UDivL);
3655       if (d) {
3656         // Replace them with a fused unsigned divmod if supported
3657         if (Matcher::has_match_rule(Op_UDivModL)) {
3658           UDivModLNode* divmod = UDivModLNode::make(n);
3659           d->subsume_by(divmod->div_proj(), this);
3660           n->subsume_by(divmod->mod_proj(), this);
3661         } else {
3662           // replace a%b with a-((a/b)*b)
3663           Node* mult = new MulLNode(d, d->in(2));
3664           Node* sub  = new SubLNode(d->in(1), mult);
3665           n->subsume_by(sub, this);
3666         }
3667       }
3668     }
3669     break;
3670 
3671   case Op_LoadVector:
3672   case Op_StoreVector:
3673   case Op_LoadVectorGather:
3674   case Op_StoreVectorScatter:
3675   case Op_LoadVectorGatherMasked:
3676   case Op_StoreVectorScatterMasked:
3677   case Op_VectorCmpMasked:
3678   case Op_VectorMaskGen:
3679   case Op_LoadVectorMasked:
3680   case Op_StoreVectorMasked:
3681     break;
3682 
3683   case Op_AddReductionVI:
3684   case Op_AddReductionVL:
3685   case Op_AddReductionVF:
3686   case Op_AddReductionVD:
3687   case Op_MulReductionVI:
3688   case Op_MulReductionVL:
3689   case Op_MulReductionVF:
3690   case Op_MulReductionVD:
3691   case Op_MinReductionV:
3692   case Op_MaxReductionV:
3693   case Op_AndReductionV:
3694   case Op_OrReductionV:
3695   case Op_XorReductionV:
3696     break;
3697 
3698   case Op_PackB:
3699   case Op_PackS:
3700   case Op_PackI:
3701   case Op_PackF:
3702   case Op_PackL:
3703   case Op_PackD:
3704     if (n->req()-1 > 2) {
3705       // Replace many operand PackNodes with a binary tree for matching
3706       PackNode* p = (PackNode*) n;
3707       Node* btp = p->binary_tree_pack(1, n->req());
3708       n->subsume_by(btp, this);
3709     }
3710     break;
3711   case Op_Loop:
3712     assert(!n->as_Loop()->is_loop_nest_inner_loop() || _loop_opts_cnt == 0, "should have been turned into a counted loop");
3713   case Op_CountedLoop:
3714   case Op_LongCountedLoop:
3715   case Op_OuterStripMinedLoop:
3716     if (n->as_Loop()->is_inner_loop()) {
3717       frc.inc_inner_loop_count();
3718     }
3719     n->as_Loop()->verify_strip_mined(0);
3720     break;
3721   case Op_LShiftI:
3722   case Op_RShiftI:
3723   case Op_URShiftI:
3724   case Op_LShiftL:
3725   case Op_RShiftL:
3726   case Op_URShiftL:
3727     if (Matcher::need_masked_shift_count) {
3728       // The cpu's shift instructions don't restrict the count to the
3729       // lower 5/6 bits. We need to do the masking ourselves.
3730       Node* in2 = n->in(2);
3731       juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
3732       const TypeInt* t = in2->find_int_type();
3733       if (t != nullptr && t->is_con()) {
3734         juint shift = t->get_con();
3735         if (shift > mask) { // Unsigned cmp
3736           n->set_req(2, ConNode::make(TypeInt::make(shift & mask)));
3737         }
3738       } else {
3739         if (t == nullptr || t->_lo < 0 || t->_hi > (int)mask) {
3740           Node* shift = new AndINode(in2, ConNode::make(TypeInt::make(mask)));
3741           n->set_req(2, shift);
3742         }
3743       }
3744       if (in2->outcnt() == 0) { // Remove dead node
3745         in2->disconnect_inputs(this);
3746       }
3747     }
3748     break;
3749   case Op_MemBarStoreStore:
3750   case Op_MemBarRelease:
3751     // Break the link with AllocateNode: it is no longer useful and
3752     // confuses register allocation.
3753     if (n->req() > MemBarNode::Precedent) {
3754       n->set_req(MemBarNode::Precedent, top());
3755     }
3756     break;
3757   case Op_MemBarAcquire: {
3758     if (n->as_MemBar()->trailing_load() && n->req() > MemBarNode::Precedent) {
3759       // At parse time, the trailing MemBarAcquire for a volatile load
3760       // is created with an edge to the load. After optimizations,
3761       // that input may be a chain of Phis. If those phis have no
3762       // other use, then the MemBarAcquire keeps them alive and
3763       // register allocation can be confused.
3764       dead_nodes.push(n->in(MemBarNode::Precedent));
3765       n->set_req(MemBarNode::Precedent, top());
3766     }
3767     break;
3768   }
3769   case Op_Blackhole:
3770     break;
3771   case Op_RangeCheck: {
3772     RangeCheckNode* rc = n->as_RangeCheck();
3773     Node* iff = new IfNode(rc->in(0), rc->in(1), rc->_prob, rc->_fcnt);
3774     n->subsume_by(iff, this);
3775     frc._tests.push(iff);
3776     break;
3777   }
3778   case Op_ConvI2L: {
3779     if (!Matcher::convi2l_type_required) {
3780       // Code generation on some platforms doesn't need accurate
3781       // ConvI2L types. Widening the type can help remove redundant
3782       // address computations.
3783       n->as_Type()->set_type(TypeLong::INT);
3784       ResourceMark rm;
3785       Unique_Node_List wq;
3786       wq.push(n);
3787       for (uint next = 0; next < wq.size(); next++) {
3788         Node *m = wq.at(next);
3789 
3790         for(;;) {
3791           // Loop over all nodes with identical inputs edges as m
3792           Node* k = m->find_similar(m->Opcode());
3793           if (k == nullptr) {
3794             break;
3795           }
3796           // Push their uses so we get a chance to remove node made
3797           // redundant
3798           for (DUIterator_Fast imax, i = k->fast_outs(imax); i < imax; i++) {
3799             Node* u = k->fast_out(i);
3800             if (u->Opcode() == Op_LShiftL ||
3801                 u->Opcode() == Op_AddL ||
3802                 u->Opcode() == Op_SubL ||
3803                 u->Opcode() == Op_AddP) {
3804               wq.push(u);
3805             }
3806           }
3807           // Replace all nodes with identical edges as m with m
3808           k->subsume_by(m, this);
3809         }
3810       }
3811     }
3812     break;
3813   }
3814   case Op_CmpUL: {
3815     if (!Matcher::has_match_rule(Op_CmpUL)) {
3816       // No support for unsigned long comparisons
3817       ConINode* sign_pos = new ConINode(TypeInt::make(BitsPerLong - 1));
3818       Node* sign_bit_mask = new RShiftLNode(n->in(1), sign_pos);
3819       Node* orl = new OrLNode(n->in(1), sign_bit_mask);
3820       ConLNode* remove_sign_mask = new ConLNode(TypeLong::make(max_jlong));
3821       Node* andl = new AndLNode(orl, remove_sign_mask);
3822       Node* cmp = new CmpLNode(andl, n->in(2));
3823       n->subsume_by(cmp, this);
3824     }
3825     break;
3826   }
3827   default:
3828     assert(!n->is_Call(), "");
3829     assert(!n->is_Mem(), "");
3830     assert(nop != Op_ProfileBoolean, "should be eliminated during IGVN");
3831     break;
3832   }
3833 }
3834 
3835 //------------------------------final_graph_reshaping_walk---------------------
3836 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
3837 // requires that the walk visits a node's inputs before visiting the node.
3838 void Compile::final_graph_reshaping_walk(Node_Stack& nstack, Node* root, Final_Reshape_Counts& frc, Unique_Node_List& dead_nodes) {
3839   Unique_Node_List sfpt;
3840 
3841   frc._visited.set(root->_idx); // first, mark node as visited
3842   uint cnt = root->req();
3843   Node *n = root;
3844   uint  i = 0;
3845   while (true) {
3846     if (i < cnt) {
3847       // Place all non-visited non-null inputs onto stack
3848       Node* m = n->in(i);
3849       ++i;
3850       if (m != nullptr && !frc._visited.test_set(m->_idx)) {
3851         if (m->is_SafePoint() && m->as_SafePoint()->jvms() != nullptr) {
3852           // compute worst case interpreter size in case of a deoptimization
3853           update_interpreter_frame_size(m->as_SafePoint()->jvms()->interpreter_frame_size());
3854 
3855           sfpt.push(m);
3856         }
3857         cnt = m->req();
3858         nstack.push(n, i); // put on stack parent and next input's index
3859         n = m;
3860         i = 0;
3861       }
3862     } else {
3863       // Now do post-visit work
3864       final_graph_reshaping_impl(n, frc, dead_nodes);
3865       if (nstack.is_empty())
3866         break;             // finished
3867       n = nstack.node();   // Get node from stack
3868       cnt = n->req();
3869       i = nstack.index();
3870       nstack.pop();        // Shift to the next node on stack
3871     }
3872   }
3873 
3874   // Skip next transformation if compressed oops are not used.
3875   if ((UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks()) ||
3876       (!UseCompressedOops && !UseCompressedClassPointers))
3877     return;
3878 
3879   // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
3880   // It could be done for an uncommon traps or any safepoints/calls
3881   // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
3882   while (sfpt.size() > 0) {
3883     n = sfpt.pop();
3884     JVMState *jvms = n->as_SafePoint()->jvms();
3885     assert(jvms != nullptr, "sanity");
3886     int start = jvms->debug_start();
3887     int end   = n->req();
3888     bool is_uncommon = (n->is_CallStaticJava() &&
3889                         n->as_CallStaticJava()->uncommon_trap_request() != 0);
3890     for (int j = start; j < end; j++) {
3891       Node* in = n->in(j);
3892       if (in->is_DecodeNarrowPtr()) {
3893         bool safe_to_skip = true;
3894         if (!is_uncommon ) {
3895           // Is it safe to skip?
3896           for (uint i = 0; i < in->outcnt(); i++) {
3897             Node* u = in->raw_out(i);
3898             if (!u->is_SafePoint() ||
3899                 (u->is_Call() && u->as_Call()->has_non_debug_use(n))) {
3900               safe_to_skip = false;
3901             }
3902           }
3903         }
3904         if (safe_to_skip) {
3905           n->set_req(j, in->in(1));
3906         }
3907         if (in->outcnt() == 0) {
3908           in->disconnect_inputs(this);
3909         }
3910       }
3911     }
3912   }
3913 }
3914 
3915 //------------------------------final_graph_reshaping--------------------------
3916 // Final Graph Reshaping.
3917 //
3918 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
3919 //     and not commoned up and forced early.  Must come after regular
3920 //     optimizations to avoid GVN undoing the cloning.  Clone constant
3921 //     inputs to Loop Phis; these will be split by the allocator anyways.
3922 //     Remove Opaque nodes.
3923 // (2) Move last-uses by commutative operations to the left input to encourage
3924 //     Intel update-in-place two-address operations and better register usage
3925 //     on RISCs.  Must come after regular optimizations to avoid GVN Ideal
3926 //     calls canonicalizing them back.
3927 // (3) Count the number of double-precision FP ops, single-precision FP ops
3928 //     and call sites.  On Intel, we can get correct rounding either by
3929 //     forcing singles to memory (requires extra stores and loads after each
3930 //     FP bytecode) or we can set a rounding mode bit (requires setting and
3931 //     clearing the mode bit around call sites).  The mode bit is only used
3932 //     if the relative frequency of single FP ops to calls is low enough.
3933 //     This is a key transform for SPEC mpeg_audio.
3934 // (4) Detect infinite loops; blobs of code reachable from above but not
3935 //     below.  Several of the Code_Gen algorithms fail on such code shapes,
3936 //     so we simply bail out.  Happens a lot in ZKM.jar, but also happens
3937 //     from time to time in other codes (such as -Xcomp finalizer loops, etc).
3938 //     Detection is by looking for IfNodes where only 1 projection is
3939 //     reachable from below or CatchNodes missing some targets.
3940 // (5) Assert for insane oop offsets in debug mode.
3941 
3942 bool Compile::final_graph_reshaping() {
3943   // an infinite loop may have been eliminated by the optimizer,
3944   // in which case the graph will be empty.
3945   if (root()->req() == 1) {
3946     // Do not compile method that is only a trivial infinite loop,
3947     // since the content of the loop may have been eliminated.
3948     record_method_not_compilable("trivial infinite loop");
3949     return true;
3950   }
3951 
3952   // Expensive nodes have their control input set to prevent the GVN
3953   // from freely commoning them. There's no GVN beyond this point so
3954   // no need to keep the control input. We want the expensive nodes to
3955   // be freely moved to the least frequent code path by gcm.
3956   assert(OptimizeExpensiveOps || expensive_count() == 0, "optimization off but list non empty?");
3957   for (int i = 0; i < expensive_count(); i++) {
3958     _expensive_nodes.at(i)->set_req(0, nullptr);
3959   }
3960 
3961   Final_Reshape_Counts frc;
3962 
3963   // Visit everybody reachable!
3964   // Allocate stack of size C->live_nodes()/2 to avoid frequent realloc
3965   Node_Stack nstack(live_nodes() >> 1);
3966   Unique_Node_List dead_nodes;
3967   final_graph_reshaping_walk(nstack, root(), frc, dead_nodes);
3968 
3969   // Check for unreachable (from below) code (i.e., infinite loops).
3970   for( uint i = 0; i < frc._tests.size(); i++ ) {
3971     MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
3972     // Get number of CFG targets.
3973     // Note that PCTables include exception targets after calls.
3974     uint required_outcnt = n->required_outcnt();
3975     if (n->outcnt() != required_outcnt) {
3976       // Check for a few special cases.  Rethrow Nodes never take the
3977       // 'fall-thru' path, so expected kids is 1 less.
3978       if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
3979         if (n->in(0)->in(0)->is_Call()) {
3980           CallNode* call = n->in(0)->in(0)->as_Call();
3981           if (call->entry_point() == OptoRuntime::rethrow_stub()) {
3982             required_outcnt--;      // Rethrow always has 1 less kid
3983           } else if (call->req() > TypeFunc::Parms &&
3984                      call->is_CallDynamicJava()) {
3985             // Check for null receiver. In such case, the optimizer has
3986             // detected that the virtual call will always result in a null
3987             // pointer exception. The fall-through projection of this CatchNode
3988             // will not be populated.
3989             Node* arg0 = call->in(TypeFunc::Parms);
3990             if (arg0->is_Type() &&
3991                 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
3992               required_outcnt--;
3993             }
3994           } else if (call->entry_point() == OptoRuntime::new_array_Java() ||
3995                      call->entry_point() == OptoRuntime::new_array_nozero_Java()) {
3996             // Check for illegal array length. In such case, the optimizer has
3997             // detected that the allocation attempt will always result in an
3998             // exception. There is no fall-through projection of this CatchNode .
3999             assert(call->is_CallStaticJava(), "static call expected");
4000             assert(call->req() == call->jvms()->endoff() + 1, "missing extra input");
4001             uint valid_length_test_input = call->req() - 1;
4002             Node* valid_length_test = call->in(valid_length_test_input);
4003             call->del_req(valid_length_test_input);
4004             if (valid_length_test->find_int_con(1) == 0) {
4005               required_outcnt--;
4006             }
4007             dead_nodes.push(valid_length_test);
4008             assert(n->outcnt() == required_outcnt, "malformed control flow");
4009             continue;
4010           }
4011         }
4012       }
4013 
4014       // Recheck with a better notion of 'required_outcnt'
4015       if (n->outcnt() != required_outcnt) {
4016         record_method_not_compilable("malformed control flow");
4017         return true;            // Not all targets reachable!
4018       }
4019     } else if (n->is_PCTable() && n->in(0) && n->in(0)->in(0) && n->in(0)->in(0)->is_Call()) {
4020       CallNode* call = n->in(0)->in(0)->as_Call();
4021       if (call->entry_point() == OptoRuntime::new_array_Java() ||
4022           call->entry_point() == OptoRuntime::new_array_nozero_Java()) {
4023         assert(call->is_CallStaticJava(), "static call expected");
4024         assert(call->req() == call->jvms()->endoff() + 1, "missing extra input");
4025         uint valid_length_test_input = call->req() - 1;
4026         dead_nodes.push(call->in(valid_length_test_input));
4027         call->del_req(valid_length_test_input); // valid length test useless now
4028       }
4029     }
4030     // Check that I actually visited all kids.  Unreached kids
4031     // must be infinite loops.
4032     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
4033       if (!frc._visited.test(n->fast_out(j)->_idx)) {
4034         record_method_not_compilable("infinite loop");
4035         return true;            // Found unvisited kid; must be unreach
4036       }
4037 
4038     // Here so verification code in final_graph_reshaping_walk()
4039     // always see an OuterStripMinedLoopEnd
4040     if (n->is_OuterStripMinedLoopEnd() || n->is_LongCountedLoopEnd()) {
4041       IfNode* init_iff = n->as_If();
4042       Node* iff = new IfNode(init_iff->in(0), init_iff->in(1), init_iff->_prob, init_iff->_fcnt);
4043       n->subsume_by(iff, this);
4044     }
4045   }
4046 
4047   while (dead_nodes.size() > 0) {
4048     Node* m = dead_nodes.pop();
4049     if (m->outcnt() == 0 && m != top()) {
4050       for (uint j = 0; j < m->req(); j++) {
4051         Node* in = m->in(j);
4052         if (in != nullptr) {
4053           dead_nodes.push(in);
4054         }
4055       }
4056       m->disconnect_inputs(this);
4057     }
4058   }
4059 
4060 #ifdef IA32
4061   // If original bytecodes contained a mixture of floats and doubles
4062   // check if the optimizer has made it homogeneous, item (3).
4063   if (UseSSE == 0 &&
4064       frc.get_float_count() > 32 &&
4065       frc.get_double_count() == 0 &&
4066       (10 * frc.get_call_count() < frc.get_float_count()) ) {
4067     set_24_bit_selection_and_mode(false, true);
4068   }
4069 #endif // IA32
4070 
4071   set_java_calls(frc.get_java_call_count());
4072   set_inner_loops(frc.get_inner_loop_count());
4073 
4074   // No infinite loops, no reason to bail out.
4075   return false;
4076 }
4077 
4078 //-----------------------------too_many_traps----------------------------------
4079 // Report if there are too many traps at the current method and bci.
4080 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
4081 bool Compile::too_many_traps(ciMethod* method,
4082                              int bci,
4083                              Deoptimization::DeoptReason reason) {
4084   ciMethodData* md = method->method_data();
4085   if (md->is_empty()) {
4086     // Assume the trap has not occurred, or that it occurred only
4087     // because of a transient condition during start-up in the interpreter.
4088     return false;
4089   }
4090   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : nullptr;
4091   if (md->has_trap_at(bci, m, reason) != 0) {
4092     // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
4093     // Also, if there are multiple reasons, or if there is no per-BCI record,
4094     // assume the worst.
4095     if (log())
4096       log()->elem("observe trap='%s' count='%d'",
4097                   Deoptimization::trap_reason_name(reason),
4098                   md->trap_count(reason));
4099     return true;
4100   } else {
4101     // Ignore method/bci and see if there have been too many globally.
4102     return too_many_traps(reason, md);
4103   }
4104 }
4105 
4106 // Less-accurate variant which does not require a method and bci.
4107 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
4108                              ciMethodData* logmd) {
4109   if (trap_count(reason) >= Deoptimization::per_method_trap_limit(reason)) {
4110     // Too many traps globally.
4111     // Note that we use cumulative trap_count, not just md->trap_count.
4112     if (log()) {
4113       int mcount = (logmd == nullptr)? -1: (int)logmd->trap_count(reason);
4114       log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
4115                   Deoptimization::trap_reason_name(reason),
4116                   mcount, trap_count(reason));
4117     }
4118     return true;
4119   } else {
4120     // The coast is clear.
4121     return false;
4122   }
4123 }
4124 
4125 //--------------------------too_many_recompiles--------------------------------
4126 // Report if there are too many recompiles at the current method and bci.
4127 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
4128 // Is not eager to return true, since this will cause the compiler to use
4129 // Action_none for a trap point, to avoid too many recompilations.
4130 bool Compile::too_many_recompiles(ciMethod* method,
4131                                   int bci,
4132                                   Deoptimization::DeoptReason reason) {
4133   ciMethodData* md = method->method_data();
4134   if (md->is_empty()) {
4135     // Assume the trap has not occurred, or that it occurred only
4136     // because of a transient condition during start-up in the interpreter.
4137     return false;
4138   }
4139   // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
4140   uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
4141   uint m_cutoff  = (uint) PerMethodRecompilationCutoff / 2 + 1;  // not zero
4142   Deoptimization::DeoptReason per_bc_reason
4143     = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
4144   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : nullptr;
4145   if ((per_bc_reason == Deoptimization::Reason_none
4146        || md->has_trap_at(bci, m, reason) != 0)
4147       // The trap frequency measure we care about is the recompile count:
4148       && md->trap_recompiled_at(bci, m)
4149       && md->overflow_recompile_count() >= bc_cutoff) {
4150     // Do not emit a trap here if it has already caused recompilations.
4151     // Also, if there are multiple reasons, or if there is no per-BCI record,
4152     // assume the worst.
4153     if (log())
4154       log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
4155                   Deoptimization::trap_reason_name(reason),
4156                   md->trap_count(reason),
4157                   md->overflow_recompile_count());
4158     return true;
4159   } else if (trap_count(reason) != 0
4160              && decompile_count() >= m_cutoff) {
4161     // Too many recompiles globally, and we have seen this sort of trap.
4162     // Use cumulative decompile_count, not just md->decompile_count.
4163     if (log())
4164       log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
4165                   Deoptimization::trap_reason_name(reason),
4166                   md->trap_count(reason), trap_count(reason),
4167                   md->decompile_count(), decompile_count());
4168     return true;
4169   } else {
4170     // The coast is clear.
4171     return false;
4172   }
4173 }
4174 
4175 // Compute when not to trap. Used by matching trap based nodes and
4176 // NullCheck optimization.
4177 void Compile::set_allowed_deopt_reasons() {
4178   _allowed_reasons = 0;
4179   if (is_method_compilation()) {
4180     for (int rs = (int)Deoptimization::Reason_none+1; rs < Compile::trapHistLength; rs++) {
4181       assert(rs < BitsPerInt, "recode bit map");
4182       if (!too_many_traps((Deoptimization::DeoptReason) rs)) {
4183         _allowed_reasons |= nth_bit(rs);
4184       }
4185     }
4186   }
4187 }
4188 
4189 bool Compile::needs_clinit_barrier(ciMethod* method, ciMethod* accessing_method) {
4190   return method->is_static() && needs_clinit_barrier(method->holder(), accessing_method);
4191 }
4192 
4193 bool Compile::needs_clinit_barrier(ciField* field, ciMethod* accessing_method) {
4194   return field->is_static() && needs_clinit_barrier(field->holder(), accessing_method);
4195 }
4196 
4197 bool Compile::needs_clinit_barrier(ciInstanceKlass* holder, ciMethod* accessing_method) {
4198   if (holder->is_initialized()) {
4199     return false;
4200   }
4201   if (holder->is_being_initialized()) {
4202     if (accessing_method->holder() == holder) {
4203       // Access inside a class. The barrier can be elided when access happens in <clinit>,
4204       // <init>, or a static method. In all those cases, there was an initialization
4205       // barrier on the holder klass passed.
4206       if (accessing_method->is_static_initializer() ||
4207           accessing_method->is_object_initializer() ||
4208           accessing_method->is_static()) {
4209         return false;
4210       }
4211     } else if (accessing_method->holder()->is_subclass_of(holder)) {
4212       // Access from a subclass. The barrier can be elided only when access happens in <clinit>.
4213       // In case of <init> or a static method, the barrier is on the subclass is not enough:
4214       // child class can become fully initialized while its parent class is still being initialized.
4215       if (accessing_method->is_static_initializer()) {
4216         return false;
4217       }
4218     }
4219     ciMethod* root = method(); // the root method of compilation
4220     if (root != accessing_method) {
4221       return needs_clinit_barrier(holder, root); // check access in the context of compilation root
4222     }
4223   }
4224   return true;
4225 }
4226 
4227 #ifndef PRODUCT
4228 //------------------------------verify_bidirectional_edges---------------------
4229 // For each input edge to a node (ie - for each Use-Def edge), verify that
4230 // there is a corresponding Def-Use edge.
4231 void Compile::verify_bidirectional_edges(Unique_Node_List &visited) {
4232   // Allocate stack of size C->live_nodes()/16 to avoid frequent realloc
4233   uint stack_size = live_nodes() >> 4;
4234   Node_List nstack(MAX2(stack_size, (uint)OptoNodeListSize));
4235   nstack.push(_root);
4236 
4237   while (nstack.size() > 0) {
4238     Node* n = nstack.pop();
4239     if (visited.member(n)) {
4240       continue;
4241     }
4242     visited.push(n);
4243 
4244     // Walk over all input edges, checking for correspondence
4245     uint length = n->len();
4246     for (uint i = 0; i < length; i++) {
4247       Node* in = n->in(i);
4248       if (in != nullptr && !visited.member(in)) {
4249         nstack.push(in); // Put it on stack
4250       }
4251       if (in != nullptr && !in->is_top()) {
4252         // Count instances of `next`
4253         int cnt = 0;
4254         for (uint idx = 0; idx < in->_outcnt; idx++) {
4255           if (in->_out[idx] == n) {
4256             cnt++;
4257           }
4258         }
4259         assert(cnt > 0, "Failed to find Def-Use edge.");
4260         // Check for duplicate edges
4261         // walk the input array downcounting the input edges to n
4262         for (uint j = 0; j < length; j++) {
4263           if (n->in(j) == in) {
4264             cnt--;
4265           }
4266         }
4267         assert(cnt == 0, "Mismatched edge count.");
4268       } else if (in == nullptr) {
4269         assert(i == 0 || i >= n->req() ||
4270                n->is_Region() || n->is_Phi() || n->is_ArrayCopy() ||
4271                (n->is_Unlock() && i == (n->req() - 1)) ||
4272                (n->is_MemBar() && i == 5), // the precedence edge to a membar can be removed during macro node expansion
4273               "only region, phi, arraycopy, unlock or membar nodes have null data edges");
4274       } else {
4275         assert(in->is_top(), "sanity");
4276         // Nothing to check.
4277       }
4278     }
4279   }
4280 }
4281 
4282 //------------------------------verify_graph_edges---------------------------
4283 // Walk the Graph and verify that there is a one-to-one correspondence
4284 // between Use-Def edges and Def-Use edges in the graph.
4285 void Compile::verify_graph_edges(bool no_dead_code) {
4286   if (VerifyGraphEdges) {
4287     Unique_Node_List visited;
4288 
4289     // Call graph walk to check edges
4290     verify_bidirectional_edges(visited);
4291     if (no_dead_code) {
4292       // Now make sure that no visited node is used by an unvisited node.
4293       bool dead_nodes = false;
4294       Unique_Node_List checked;
4295       while (visited.size() > 0) {
4296         Node* n = visited.pop();
4297         checked.push(n);
4298         for (uint i = 0; i < n->outcnt(); i++) {
4299           Node* use = n->raw_out(i);
4300           if (checked.member(use))  continue;  // already checked
4301           if (visited.member(use))  continue;  // already in the graph
4302           if (use->is_Con())        continue;  // a dead ConNode is OK
4303           // At this point, we have found a dead node which is DU-reachable.
4304           if (!dead_nodes) {
4305             tty->print_cr("*** Dead nodes reachable via DU edges:");
4306             dead_nodes = true;
4307           }
4308           use->dump(2);
4309           tty->print_cr("---");
4310           checked.push(use);  // No repeats; pretend it is now checked.
4311         }
4312       }
4313       assert(!dead_nodes, "using nodes must be reachable from root");
4314     }
4315   }
4316 }
4317 #endif
4318 
4319 // The Compile object keeps track of failure reasons separately from the ciEnv.
4320 // This is required because there is not quite a 1-1 relation between the
4321 // ciEnv and its compilation task and the Compile object.  Note that one
4322 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
4323 // to backtrack and retry without subsuming loads.  Other than this backtracking
4324 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
4325 // by the logic in C2Compiler.
4326 void Compile::record_failure(const char* reason) {
4327   if (log() != nullptr) {
4328     log()->elem("failure reason='%s' phase='compile'", reason);
4329   }
4330   if (_failure_reason.get() == nullptr) {
4331     // Record the first failure reason.
4332     _failure_reason.set(reason);
4333   }
4334 
4335   if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
4336     C->print_method(PHASE_FAILURE, 1);
4337   }
4338   _root = nullptr;  // flush the graph, too
4339 }
4340 
4341 Compile::TracePhase::TracePhase(const char* name, elapsedTimer* accumulator)
4342   : TraceTime(name, accumulator, CITime, CITimeVerbose),
4343     _phase_name(name), _dolog(CITimeVerbose)
4344 {
4345   if (_dolog) {
4346     C = Compile::current();
4347     _log = C->log();
4348   } else {
4349     C = nullptr;
4350     _log = nullptr;
4351   }
4352   if (_log != nullptr) {
4353     _log->begin_head("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
4354     _log->stamp();
4355     _log->end_head();
4356   }
4357 }
4358 
4359 Compile::TracePhase::~TracePhase() {
4360 
4361   C = Compile::current();
4362   if (_dolog) {
4363     _log = C->log();
4364   } else {
4365     _log = nullptr;
4366   }
4367 
4368 #ifdef ASSERT
4369   if (PrintIdealNodeCount) {
4370     tty->print_cr("phase name='%s' nodes='%d' live='%d' live_graph_walk='%d'",
4371                   _phase_name, C->unique(), C->live_nodes(), C->count_live_nodes_by_graph_walk());
4372   }
4373 
4374   if (VerifyIdealNodeCount) {
4375     Compile::current()->print_missing_nodes();
4376   }
4377 #endif
4378 
4379   if (_log != nullptr) {
4380     _log->done("phase name='%s' nodes='%d' live='%d'", _phase_name, C->unique(), C->live_nodes());
4381   }
4382 }
4383 
4384 //----------------------------static_subtype_check-----------------------------
4385 // Shortcut important common cases when superklass is exact:
4386 // (0) superklass is java.lang.Object (can occur in reflective code)
4387 // (1) subklass is already limited to a subtype of superklass => always ok
4388 // (2) subklass does not overlap with superklass => always fail
4389 // (3) superklass has NO subtypes and we can check with a simple compare.
4390 Compile::SubTypeCheckResult Compile::static_subtype_check(const TypeKlassPtr* superk, const TypeKlassPtr* subk, bool skip) {
4391   if (skip) {
4392     return SSC_full_test;       // Let caller generate the general case.
4393   }
4394 
4395   if (subk->is_java_subtype_of(superk)) {
4396     return SSC_always_true; // (0) and (1)  this test cannot fail
4397   }
4398 
4399   if (!subk->maybe_java_subtype_of(superk)) {
4400     return SSC_always_false; // (2) true path dead; no dynamic test needed
4401   }
4402 
4403   const Type* superelem = superk;
4404   if (superk->isa_aryklassptr()) {
4405     int ignored;
4406     superelem = superk->is_aryklassptr()->base_element_type(ignored);
4407   }
4408 
4409   if (superelem->isa_instklassptr()) {
4410     ciInstanceKlass* ik = superelem->is_instklassptr()->instance_klass();
4411     if (!ik->has_subklass()) {
4412       if (!ik->is_final()) {
4413         // Add a dependency if there is a chance of a later subclass.
4414         dependencies()->assert_leaf_type(ik);
4415       }
4416       if (!superk->maybe_java_subtype_of(subk)) {
4417         return SSC_always_false;
4418       }
4419       return SSC_easy_test;     // (3) caller can do a simple ptr comparison
4420     }
4421   } else {
4422     // A primitive array type has no subtypes.
4423     return SSC_easy_test;       // (3) caller can do a simple ptr comparison
4424   }
4425 
4426   return SSC_full_test;
4427 }
4428 
4429 Node* Compile::conv_I2X_index(PhaseGVN* phase, Node* idx, const TypeInt* sizetype, Node* ctrl) {
4430 #ifdef _LP64
4431   // The scaled index operand to AddP must be a clean 64-bit value.
4432   // Java allows a 32-bit int to be incremented to a negative
4433   // value, which appears in a 64-bit register as a large
4434   // positive number.  Using that large positive number as an
4435   // operand in pointer arithmetic has bad consequences.
4436   // On the other hand, 32-bit overflow is rare, and the possibility
4437   // can often be excluded, if we annotate the ConvI2L node with
4438   // a type assertion that its value is known to be a small positive
4439   // number.  (The prior range check has ensured this.)
4440   // This assertion is used by ConvI2LNode::Ideal.
4441   int index_max = max_jint - 1;  // array size is max_jint, index is one less
4442   if (sizetype != nullptr) index_max = sizetype->_hi - 1;
4443   const TypeInt* iidxtype = TypeInt::make(0, index_max, Type::WidenMax);
4444   idx = constrained_convI2L(phase, idx, iidxtype, ctrl);
4445 #endif
4446   return idx;
4447 }
4448 
4449 // Convert integer value to a narrowed long type dependent on ctrl (for example, a range check)
4450 Node* Compile::constrained_convI2L(PhaseGVN* phase, Node* value, const TypeInt* itype, Node* ctrl, bool carry_dependency) {
4451   if (ctrl != nullptr) {
4452     // Express control dependency by a CastII node with a narrow type.
4453     value = new CastIINode(value, itype, carry_dependency ? ConstraintCastNode::StrongDependency : ConstraintCastNode::RegularDependency, true /* range check dependency */);
4454     // Make the CastII node dependent on the control input to prevent the narrowed ConvI2L
4455     // node from floating above the range check during loop optimizations. Otherwise, the
4456     // ConvI2L node may be eliminated independently of the range check, causing the data path
4457     // to become TOP while the control path is still there (although it's unreachable).
4458     value->set_req(0, ctrl);
4459     value = phase->transform(value);
4460   }
4461   const TypeLong* ltype = TypeLong::make(itype->_lo, itype->_hi, itype->_widen);
4462   return phase->transform(new ConvI2LNode(value, ltype));
4463 }
4464 
4465 // The message about the current inlining is accumulated in
4466 // _print_inlining_stream and transferred into the _print_inlining_list
4467 // once we know whether inlining succeeds or not. For regular
4468 // inlining, messages are appended to the buffer pointed by
4469 // _print_inlining_idx in the _print_inlining_list. For late inlining,
4470 // a new buffer is added after _print_inlining_idx in the list. This
4471 // way we can update the inlining message for late inlining call site
4472 // when the inlining is attempted again.
4473 void Compile::print_inlining_init() {
4474   if (print_inlining() || print_intrinsics()) {
4475     // print_inlining_init is actually called several times.
4476     print_inlining_reset();
4477     _print_inlining_list = new (comp_arena())GrowableArray<PrintInliningBuffer*>(comp_arena(), 1, 1, new PrintInliningBuffer());
4478   }
4479 }
4480 
4481 void Compile::print_inlining_reinit() {
4482   if (print_inlining() || print_intrinsics()) {
4483     print_inlining_reset();
4484   }
4485 }
4486 
4487 void Compile::print_inlining_reset() {
4488   _print_inlining_stream->reset();
4489 }
4490 
4491 void Compile::print_inlining_commit() {
4492   assert(print_inlining() || print_intrinsics(), "PrintInlining off?");
4493   // Transfer the message from _print_inlining_stream to the current
4494   // _print_inlining_list buffer and clear _print_inlining_stream.
4495   _print_inlining_list->at(_print_inlining_idx)->ss()->write(_print_inlining_stream->base(), _print_inlining_stream->size());
4496   print_inlining_reset();
4497 }
4498 
4499 void Compile::print_inlining_push() {
4500   // Add new buffer to the _print_inlining_list at current position
4501   _print_inlining_idx++;
4502   _print_inlining_list->insert_before(_print_inlining_idx, new PrintInliningBuffer());
4503 }
4504 
4505 Compile::PrintInliningBuffer* Compile::print_inlining_current() {
4506   return _print_inlining_list->at(_print_inlining_idx);
4507 }
4508 
4509 void Compile::print_inlining_update(CallGenerator* cg) {
4510   if (print_inlining() || print_intrinsics()) {
4511     if (cg->is_late_inline()) {
4512       if (print_inlining_current()->cg() != cg &&
4513           (print_inlining_current()->cg() != nullptr ||
4514            print_inlining_current()->ss()->size() != 0)) {
4515         print_inlining_push();
4516       }
4517       print_inlining_commit();
4518       print_inlining_current()->set_cg(cg);
4519     } else {
4520       if (print_inlining_current()->cg() != nullptr) {
4521         print_inlining_push();
4522       }
4523       print_inlining_commit();
4524     }
4525   }
4526 }
4527 
4528 void Compile::print_inlining_move_to(CallGenerator* cg) {
4529   // We resume inlining at a late inlining call site. Locate the
4530   // corresponding inlining buffer so that we can update it.
4531   if (print_inlining() || print_intrinsics()) {
4532     for (int i = 0; i < _print_inlining_list->length(); i++) {
4533       if (_print_inlining_list->at(i)->cg() == cg) {
4534         _print_inlining_idx = i;
4535         return;
4536       }
4537     }
4538     ShouldNotReachHere();
4539   }
4540 }
4541 
4542 void Compile::print_inlining_update_delayed(CallGenerator* cg) {
4543   if (print_inlining() || print_intrinsics()) {
4544     assert(_print_inlining_stream->size() > 0, "missing inlining msg");
4545     assert(print_inlining_current()->cg() == cg, "wrong entry");
4546     // replace message with new message
4547     _print_inlining_list->at_put(_print_inlining_idx, new PrintInliningBuffer());
4548     print_inlining_commit();
4549     print_inlining_current()->set_cg(cg);
4550   }
4551 }
4552 
4553 void Compile::print_inlining_assert_ready() {
4554   assert(!_print_inlining || _print_inlining_stream->size() == 0, "losing data");
4555 }
4556 
4557 void Compile::process_print_inlining() {
4558   assert(_late_inlines.length() == 0, "not drained yet");
4559   if (print_inlining() || print_intrinsics()) {
4560     ResourceMark rm;
4561     stringStream ss;
4562     assert(_print_inlining_list != nullptr, "process_print_inlining should be called only once.");
4563     for (int i = 0; i < _print_inlining_list->length(); i++) {
4564       PrintInliningBuffer* pib = _print_inlining_list->at(i);
4565       ss.print("%s", pib->ss()->freeze());
4566       delete pib;
4567       DEBUG_ONLY(_print_inlining_list->at_put(i, nullptr));
4568     }
4569     // Reset _print_inlining_list, it only contains destructed objects.
4570     // It is on the arena, so it will be freed when the arena is reset.
4571     _print_inlining_list = nullptr;
4572     // _print_inlining_stream won't be used anymore, either.
4573     print_inlining_reset();
4574     size_t end = ss.size();
4575     _print_inlining_output = NEW_ARENA_ARRAY(comp_arena(), char, end+1);
4576     strncpy(_print_inlining_output, ss.freeze(), end+1);
4577     _print_inlining_output[end] = 0;
4578   }
4579 }
4580 
4581 void Compile::dump_print_inlining() {
4582   if (_print_inlining_output != nullptr) {
4583     tty->print_raw(_print_inlining_output);
4584   }
4585 }
4586 
4587 void Compile::log_late_inline(CallGenerator* cg) {
4588   if (log() != nullptr) {
4589     log()->head("late_inline method='%d'  inline_id='" JLONG_FORMAT "'", log()->identify(cg->method()),
4590                 cg->unique_id());
4591     JVMState* p = cg->call_node()->jvms();
4592     while (p != nullptr) {
4593       log()->elem("jvms bci='%d' method='%d'", p->bci(), log()->identify(p->method()));
4594       p = p->caller();
4595     }
4596     log()->tail("late_inline");
4597   }
4598 }
4599 
4600 void Compile::log_late_inline_failure(CallGenerator* cg, const char* msg) {
4601   log_late_inline(cg);
4602   if (log() != nullptr) {
4603     log()->inline_fail(msg);
4604   }
4605 }
4606 
4607 void Compile::log_inline_id(CallGenerator* cg) {
4608   if (log() != nullptr) {
4609     // The LogCompilation tool needs a unique way to identify late
4610     // inline call sites. This id must be unique for this call site in
4611     // this compilation. Try to have it unique across compilations as
4612     // well because it can be convenient when grepping through the log
4613     // file.
4614     // Distinguish OSR compilations from others in case CICountOSR is
4615     // on.
4616     jlong id = ((jlong)unique()) + (((jlong)compile_id()) << 33) + (CICountOSR && is_osr_compilation() ? ((jlong)1) << 32 : 0);
4617     cg->set_unique_id(id);
4618     log()->elem("inline_id id='" JLONG_FORMAT "'", id);
4619   }
4620 }
4621 
4622 void Compile::log_inline_failure(const char* msg) {
4623   if (C->log() != nullptr) {
4624     C->log()->inline_fail(msg);
4625   }
4626 }
4627 
4628 
4629 // Dump inlining replay data to the stream.
4630 // Don't change thread state and acquire any locks.
4631 void Compile::dump_inline_data(outputStream* out) {
4632   InlineTree* inl_tree = ilt();
4633   if (inl_tree != nullptr) {
4634     out->print(" inline %d", inl_tree->count());
4635     inl_tree->dump_replay_data(out);
4636   }
4637 }
4638 
4639 void Compile::dump_inline_data_reduced(outputStream* out) {
4640   assert(ReplayReduce, "");
4641 
4642   InlineTree* inl_tree = ilt();
4643   if (inl_tree == nullptr) {
4644     return;
4645   }
4646   // Enable iterative replay file reduction
4647   // Output "compile" lines for depth 1 subtrees,
4648   // simulating that those trees were compiled
4649   // instead of inlined.
4650   for (int i = 0; i < inl_tree->subtrees().length(); ++i) {
4651     InlineTree* sub = inl_tree->subtrees().at(i);
4652     if (sub->inline_level() != 1) {
4653       continue;
4654     }
4655 
4656     ciMethod* method = sub->method();
4657     int entry_bci = -1;
4658     int comp_level = env()->task()->comp_level();
4659     out->print("compile ");
4660     method->dump_name_as_ascii(out);
4661     out->print(" %d %d", entry_bci, comp_level);
4662     out->print(" inline %d", sub->count());
4663     sub->dump_replay_data(out, -1);
4664     out->cr();
4665   }
4666 }
4667 
4668 int Compile::cmp_expensive_nodes(Node* n1, Node* n2) {
4669   if (n1->Opcode() < n2->Opcode())      return -1;
4670   else if (n1->Opcode() > n2->Opcode()) return 1;
4671 
4672   assert(n1->req() == n2->req(), "can't compare %s nodes: n1->req() = %d, n2->req() = %d", NodeClassNames[n1->Opcode()], n1->req(), n2->req());
4673   for (uint i = 1; i < n1->req(); i++) {
4674     if (n1->in(i) < n2->in(i))      return -1;
4675     else if (n1->in(i) > n2->in(i)) return 1;
4676   }
4677 
4678   return 0;
4679 }
4680 
4681 int Compile::cmp_expensive_nodes(Node** n1p, Node** n2p) {
4682   Node* n1 = *n1p;
4683   Node* n2 = *n2p;
4684 
4685   return cmp_expensive_nodes(n1, n2);
4686 }
4687 
4688 void Compile::sort_expensive_nodes() {
4689   if (!expensive_nodes_sorted()) {
4690     _expensive_nodes.sort(cmp_expensive_nodes);
4691   }
4692 }
4693 
4694 bool Compile::expensive_nodes_sorted() const {
4695   for (int i = 1; i < _expensive_nodes.length(); i++) {
4696     if (cmp_expensive_nodes(_expensive_nodes.adr_at(i), _expensive_nodes.adr_at(i-1)) < 0) {
4697       return false;
4698     }
4699   }
4700   return true;
4701 }
4702 
4703 bool Compile::should_optimize_expensive_nodes(PhaseIterGVN &igvn) {
4704   if (_expensive_nodes.length() == 0) {
4705     return false;
4706   }
4707 
4708   assert(OptimizeExpensiveOps, "optimization off?");
4709 
4710   // Take this opportunity to remove dead nodes from the list
4711   int j = 0;
4712   for (int i = 0; i < _expensive_nodes.length(); i++) {
4713     Node* n = _expensive_nodes.at(i);
4714     if (!n->is_unreachable(igvn)) {
4715       assert(n->is_expensive(), "should be expensive");
4716       _expensive_nodes.at_put(j, n);
4717       j++;
4718     }
4719   }
4720   _expensive_nodes.trunc_to(j);
4721 
4722   // Then sort the list so that similar nodes are next to each other
4723   // and check for at least two nodes of identical kind with same data
4724   // inputs.
4725   sort_expensive_nodes();
4726 
4727   for (int i = 0; i < _expensive_nodes.length()-1; i++) {
4728     if (cmp_expensive_nodes(_expensive_nodes.adr_at(i), _expensive_nodes.adr_at(i+1)) == 0) {
4729       return true;
4730     }
4731   }
4732 
4733   return false;
4734 }
4735 
4736 void Compile::cleanup_expensive_nodes(PhaseIterGVN &igvn) {
4737   if (_expensive_nodes.length() == 0) {
4738     return;
4739   }
4740 
4741   assert(OptimizeExpensiveOps, "optimization off?");
4742 
4743   // Sort to bring similar nodes next to each other and clear the
4744   // control input of nodes for which there's only a single copy.
4745   sort_expensive_nodes();
4746 
4747   int j = 0;
4748   int identical = 0;
4749   int i = 0;
4750   bool modified = false;
4751   for (; i < _expensive_nodes.length()-1; i++) {
4752     assert(j <= i, "can't write beyond current index");
4753     if (_expensive_nodes.at(i)->Opcode() == _expensive_nodes.at(i+1)->Opcode()) {
4754       identical++;
4755       _expensive_nodes.at_put(j++, _expensive_nodes.at(i));
4756       continue;
4757     }
4758     if (identical > 0) {
4759       _expensive_nodes.at_put(j++, _expensive_nodes.at(i));
4760       identical = 0;
4761     } else {
4762       Node* n = _expensive_nodes.at(i);
4763       igvn.replace_input_of(n, 0, nullptr);
4764       igvn.hash_insert(n);
4765       modified = true;
4766     }
4767   }
4768   if (identical > 0) {
4769     _expensive_nodes.at_put(j++, _expensive_nodes.at(i));
4770   } else if (_expensive_nodes.length() >= 1) {
4771     Node* n = _expensive_nodes.at(i);
4772     igvn.replace_input_of(n, 0, nullptr);
4773     igvn.hash_insert(n);
4774     modified = true;
4775   }
4776   _expensive_nodes.trunc_to(j);
4777   if (modified) {
4778     igvn.optimize();
4779   }
4780 }
4781 
4782 void Compile::add_expensive_node(Node * n) {
4783   assert(!_expensive_nodes.contains(n), "duplicate entry in expensive list");
4784   assert(n->is_expensive(), "expensive nodes with non-null control here only");
4785   assert(!n->is_CFG() && !n->is_Mem(), "no cfg or memory nodes here");
4786   if (OptimizeExpensiveOps) {
4787     _expensive_nodes.append(n);
4788   } else {
4789     // Clear control input and let IGVN optimize expensive nodes if
4790     // OptimizeExpensiveOps is off.
4791     n->set_req(0, nullptr);
4792   }
4793 }
4794 
4795 /**
4796  * Track coarsened Lock and Unlock nodes.
4797  */
4798 
4799 class Lock_List : public Node_List {
4800   uint _origin_cnt;
4801 public:
4802   Lock_List(Arena *a, uint cnt) : Node_List(a), _origin_cnt(cnt) {}
4803   uint origin_cnt() const { return _origin_cnt; }
4804 };
4805 
4806 void Compile::add_coarsened_locks(GrowableArray<AbstractLockNode*>& locks) {
4807   int length = locks.length();
4808   if (length > 0) {
4809     // Have to keep this list until locks elimination during Macro nodes elimination.
4810     Lock_List* locks_list = new (comp_arena()) Lock_List(comp_arena(), length);
4811     AbstractLockNode* alock = locks.at(0);
4812     BoxLockNode* box = alock->box_node()->as_BoxLock();
4813     for (int i = 0; i < length; i++) {
4814       AbstractLockNode* lock = locks.at(i);
4815       assert(lock->is_coarsened(), "expecting only coarsened AbstractLock nodes, but got '%s'[%d] node", lock->Name(), lock->_idx);
4816       locks_list->push(lock);
4817       BoxLockNode* this_box = lock->box_node()->as_BoxLock();
4818       if (this_box != box) {
4819         // Locking regions (BoxLock) could be Unbalanced here:
4820         //  - its coarsened locks were eliminated in earlier
4821         //    macro nodes elimination followed by loop unroll
4822         //  - it is OSR locking region (no Lock node)
4823         // Preserve Unbalanced status in such cases.
4824         if (!this_box->is_unbalanced()) {
4825           this_box->set_coarsened();
4826         }
4827         if (!box->is_unbalanced()) {
4828           box->set_coarsened();
4829         }
4830       }
4831     }
4832     _coarsened_locks.append(locks_list);
4833   }
4834 }
4835 
4836 void Compile::remove_useless_coarsened_locks(Unique_Node_List& useful) {
4837   int count = coarsened_count();
4838   for (int i = 0; i < count; i++) {
4839     Node_List* locks_list = _coarsened_locks.at(i);
4840     for (uint j = 0; j < locks_list->size(); j++) {
4841       Node* lock = locks_list->at(j);
4842       assert(lock->is_AbstractLock(), "sanity");
4843       if (!useful.member(lock)) {
4844         locks_list->yank(lock);
4845       }
4846     }
4847   }
4848 }
4849 
4850 void Compile::remove_coarsened_lock(Node* n) {
4851   if (n->is_AbstractLock()) {
4852     int count = coarsened_count();
4853     for (int i = 0; i < count; i++) {
4854       Node_List* locks_list = _coarsened_locks.at(i);
4855       locks_list->yank(n);
4856     }
4857   }
4858 }
4859 
4860 bool Compile::coarsened_locks_consistent() {
4861   int count = coarsened_count();
4862   for (int i = 0; i < count; i++) {
4863     bool unbalanced = false;
4864     bool modified = false; // track locks kind modifications
4865     Lock_List* locks_list = (Lock_List*)_coarsened_locks.at(i);
4866     uint size = locks_list->size();
4867     if (size == 0) {
4868       unbalanced = false; // All locks were eliminated - good
4869     } else if (size != locks_list->origin_cnt()) {
4870       unbalanced = true; // Some locks were removed from list
4871     } else {
4872       for (uint j = 0; j < size; j++) {
4873         Node* lock = locks_list->at(j);
4874         // All nodes in group should have the same state (modified or not)
4875         if (!lock->as_AbstractLock()->is_coarsened()) {
4876           if (j == 0) {
4877             // first on list was modified, the rest should be too for consistency
4878             modified = true;
4879           } else if (!modified) {
4880             // this lock was modified but previous locks on the list were not
4881             unbalanced = true;
4882             break;
4883           }
4884         } else if (modified) {
4885           // previous locks on list were modified but not this lock
4886           unbalanced = true;
4887           break;
4888         }
4889       }
4890     }
4891     if (unbalanced) {
4892       // unbalanced monitor enter/exit - only some [un]lock nodes were removed or modified
4893 #ifdef ASSERT
4894       if (PrintEliminateLocks) {
4895         tty->print_cr("=== unbalanced coarsened locks ===");
4896         for (uint l = 0; l < size; l++) {
4897           locks_list->at(l)->dump();
4898         }
4899       }
4900 #endif
4901       record_failure(C2Compiler::retry_no_locks_coarsening());
4902       return false;
4903     }
4904   }
4905   return true;
4906 }
4907 
4908 // Mark locking regions (identified by BoxLockNode) as unbalanced if
4909 // locks coarsening optimization removed Lock/Unlock nodes from them.
4910 // Such regions become unbalanced because coarsening only removes part
4911 // of Lock/Unlock nodes in region. As result we can't execute other
4912 // locks elimination optimizations which assume all code paths have
4913 // corresponding pair of Lock/Unlock nodes - they are balanced.
4914 void Compile::mark_unbalanced_boxes() const {
4915   int count = coarsened_count();
4916   for (int i = 0; i < count; i++) {
4917     Node_List* locks_list = _coarsened_locks.at(i);
4918     uint size = locks_list->size();
4919     if (size > 0) {
4920       AbstractLockNode* alock = locks_list->at(0)->as_AbstractLock();
4921       BoxLockNode* box = alock->box_node()->as_BoxLock();
4922       if (alock->is_coarsened()) {
4923         // coarsened_locks_consistent(), which is called before this method, verifies
4924         // that the rest of Lock/Unlock nodes on locks_list are also coarsened.
4925         assert(!box->is_eliminated(), "regions with coarsened locks should not be marked as eliminated");
4926         for (uint j = 1; j < size; j++) {
4927           assert(locks_list->at(j)->as_AbstractLock()->is_coarsened(), "only coarsened locks are expected here");
4928           BoxLockNode* this_box = locks_list->at(j)->as_AbstractLock()->box_node()->as_BoxLock();
4929           if (box != this_box) {
4930             assert(!this_box->is_eliminated(), "regions with coarsened locks should not be marked as eliminated");
4931             box->set_unbalanced();
4932             this_box->set_unbalanced();
4933           }
4934         }
4935       }
4936     }
4937   }
4938 }
4939 
4940 /**
4941  * Remove the speculative part of types and clean up the graph
4942  */
4943 void Compile::remove_speculative_types(PhaseIterGVN &igvn) {
4944   if (UseTypeSpeculation) {
4945     Unique_Node_List worklist;
4946     worklist.push(root());
4947     int modified = 0;
4948     // Go over all type nodes that carry a speculative type, drop the
4949     // speculative part of the type and enqueue the node for an igvn
4950     // which may optimize it out.
4951     for (uint next = 0; next < worklist.size(); ++next) {
4952       Node *n  = worklist.at(next);
4953       if (n->is_Type()) {
4954         TypeNode* tn = n->as_Type();
4955         const Type* t = tn->type();
4956         const Type* t_no_spec = t->remove_speculative();
4957         if (t_no_spec != t) {
4958           bool in_hash = igvn.hash_delete(n);
4959 #ifdef ASSERT
4960           if (!in_hash) {
4961             tty->print_cr("current graph:");
4962             n->dump_bfs(MaxNodeLimit, nullptr, "S$");
4963             tty->cr();
4964             tty->print_cr("erroneous node:");
4965             n->dump();
4966             assert(false, "node should be in igvn hash table");
4967           }
4968 #endif
4969           tn->set_type(t_no_spec);
4970           igvn.hash_insert(n);
4971           igvn._worklist.push(n); // give it a chance to go away
4972           modified++;
4973         }
4974       }
4975       // Iterate over outs - endless loops is unreachable from below
4976       for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
4977         Node *m = n->fast_out(i);
4978         if (not_a_node(m)) {
4979           continue;
4980         }
4981         worklist.push(m);
4982       }
4983     }
4984     // Drop the speculative part of all types in the igvn's type table
4985     igvn.remove_speculative_types();
4986     if (modified > 0) {
4987       igvn.optimize();
4988       if (failing())  return;
4989     }
4990 #ifdef ASSERT
4991     // Verify that after the IGVN is over no speculative type has resurfaced
4992     worklist.clear();
4993     worklist.push(root());
4994     for (uint next = 0; next < worklist.size(); ++next) {
4995       Node *n  = worklist.at(next);
4996       const Type* t = igvn.type_or_null(n);
4997       assert((t == nullptr) || (t == t->remove_speculative()), "no more speculative types");
4998       if (n->is_Type()) {
4999         t = n->as_Type()->type();
5000         assert(t == t->remove_speculative(), "no more speculative types");
5001       }
5002       // Iterate over outs - endless loops is unreachable from below
5003       for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
5004         Node *m = n->fast_out(i);
5005         if (not_a_node(m)) {
5006           continue;
5007         }
5008         worklist.push(m);
5009       }
5010     }
5011     igvn.check_no_speculative_types();
5012 #endif
5013   }
5014 }
5015 
5016 // Auxiliary methods to support randomized stressing/fuzzing.
5017 
5018 int Compile::random() {
5019   _stress_seed = os::next_random(_stress_seed);
5020   return static_cast<int>(_stress_seed);
5021 }
5022 
5023 // This method can be called the arbitrary number of times, with current count
5024 // as the argument. The logic allows selecting a single candidate from the
5025 // running list of candidates as follows:
5026 //    int count = 0;
5027 //    Cand* selected = null;
5028 //    while(cand = cand->next()) {
5029 //      if (randomized_select(++count)) {
5030 //        selected = cand;
5031 //      }
5032 //    }
5033 //
5034 // Including count equalizes the chances any candidate is "selected".
5035 // This is useful when we don't have the complete list of candidates to choose
5036 // from uniformly. In this case, we need to adjust the randomicity of the
5037 // selection, or else we will end up biasing the selection towards the latter
5038 // candidates.
5039 //
5040 // Quick back-envelope calculation shows that for the list of n candidates
5041 // the equal probability for the candidate to persist as "best" can be
5042 // achieved by replacing it with "next" k-th candidate with the probability
5043 // of 1/k. It can be easily shown that by the end of the run, the
5044 // probability for any candidate is converged to 1/n, thus giving the
5045 // uniform distribution among all the candidates.
5046 //
5047 // We don't care about the domain size as long as (RANDOMIZED_DOMAIN / count) is large.
5048 #define RANDOMIZED_DOMAIN_POW 29
5049 #define RANDOMIZED_DOMAIN (1 << RANDOMIZED_DOMAIN_POW)
5050 #define RANDOMIZED_DOMAIN_MASK ((1 << (RANDOMIZED_DOMAIN_POW + 1)) - 1)
5051 bool Compile::randomized_select(int count) {
5052   assert(count > 0, "only positive");
5053   return (random() & RANDOMIZED_DOMAIN_MASK) < (RANDOMIZED_DOMAIN / count);
5054 }
5055 
5056 CloneMap&     Compile::clone_map()                 { return _clone_map; }
5057 void          Compile::set_clone_map(Dict* d)      { _clone_map._dict = d; }
5058 
5059 void NodeCloneInfo::dump_on(outputStream* st) const {
5060   st->print(" {%d:%d} ", idx(), gen());
5061 }
5062 
5063 void CloneMap::clone(Node* old, Node* nnn, int gen) {
5064   uint64_t val = value(old->_idx);
5065   NodeCloneInfo cio(val);
5066   assert(val != 0, "old node should be in the map");
5067   NodeCloneInfo cin(cio.idx(), gen + cio.gen());
5068   insert(nnn->_idx, cin.get());
5069 #ifndef PRODUCT
5070   if (is_debug()) {
5071     tty->print_cr("CloneMap::clone inserted node %d info {%d:%d} into CloneMap", nnn->_idx, cin.idx(), cin.gen());
5072   }
5073 #endif
5074 }
5075 
5076 void CloneMap::verify_insert_and_clone(Node* old, Node* nnn, int gen) {
5077   NodeCloneInfo cio(value(old->_idx));
5078   if (cio.get() == 0) {
5079     cio.set(old->_idx, 0);
5080     insert(old->_idx, cio.get());
5081 #ifndef PRODUCT
5082     if (is_debug()) {
5083       tty->print_cr("CloneMap::verify_insert_and_clone inserted node %d info {%d:%d} into CloneMap", old->_idx, cio.idx(), cio.gen());
5084     }
5085 #endif
5086   }
5087   clone(old, nnn, gen);
5088 }
5089 
5090 int CloneMap::max_gen() const {
5091   int g = 0;
5092   DictI di(_dict);
5093   for(; di.test(); ++di) {
5094     int t = gen(di._key);
5095     if (g < t) {
5096       g = t;
5097 #ifndef PRODUCT
5098       if (is_debug()) {
5099         tty->print_cr("CloneMap::max_gen() update max=%d from %d", g, _2_node_idx_t(di._key));
5100       }
5101 #endif
5102     }
5103   }
5104   return g;
5105 }
5106 
5107 void CloneMap::dump(node_idx_t key, outputStream* st) const {
5108   uint64_t val = value(key);
5109   if (val != 0) {
5110     NodeCloneInfo ni(val);
5111     ni.dump_on(st);
5112   }
5113 }
5114 
5115 // Move Allocate nodes to the start of the list
5116 void Compile::sort_macro_nodes() {
5117   int count = macro_count();
5118   int allocates = 0;
5119   for (int i = 0; i < count; i++) {
5120     Node* n = macro_node(i);
5121     if (n->is_Allocate()) {
5122       if (i != allocates) {
5123         Node* tmp = macro_node(allocates);
5124         _macro_nodes.at_put(allocates, n);
5125         _macro_nodes.at_put(i, tmp);
5126       }
5127       allocates++;
5128     }
5129   }
5130 }
5131 
5132 void Compile::print_method(CompilerPhaseType cpt, int level, Node* n) {
5133   EventCompilerPhase event;
5134   if (event.should_commit()) {
5135     CompilerEvent::PhaseEvent::post(event, C->_latest_stage_start_counter, cpt, C->_compile_id, level);
5136   }
5137 #ifndef PRODUCT
5138   ResourceMark rm;
5139   stringStream ss;
5140   ss.print_raw(CompilerPhaseTypeHelper::to_description(cpt));
5141   if (n != nullptr) {
5142     ss.print(": %d %s ", n->_idx, NodeClassNames[n->Opcode()]);
5143   }
5144 
5145   const char* name = ss.as_string();
5146   if (should_print_igv(level)) {
5147     _igv_printer->print_method(name, level);
5148   }
5149   if (should_print_phase(cpt)) {
5150     print_ideal_ir(CompilerPhaseTypeHelper::to_name(cpt));
5151   }
5152 #endif
5153   C->_latest_stage_start_counter.stamp();
5154 }
5155 
5156 // Only used from CompileWrapper
5157 void Compile::begin_method() {
5158 #ifndef PRODUCT
5159   if (_method != nullptr && should_print_igv(1)) {
5160     _igv_printer->begin_method();
5161   }
5162 #endif
5163   C->_latest_stage_start_counter.stamp();
5164 }
5165 
5166 // Only used from CompileWrapper
5167 void Compile::end_method() {
5168   EventCompilerPhase event;
5169   if (event.should_commit()) {
5170     CompilerEvent::PhaseEvent::post(event, C->_latest_stage_start_counter, PHASE_END, C->_compile_id, 1);
5171   }
5172 
5173 #ifndef PRODUCT
5174   if (_method != nullptr && should_print_igv(1)) {
5175     _igv_printer->end_method();
5176   }
5177 #endif
5178 }
5179 
5180 bool Compile::should_print_phase(CompilerPhaseType cpt) {
5181 #ifndef PRODUCT
5182   if ((_directive->ideal_phase_mask() & CompilerPhaseTypeHelper::to_bitmask(cpt)) != 0) {
5183     return true;
5184   }
5185 #endif
5186   return false;
5187 }
5188 
5189 bool Compile::should_print_igv(int level) {
5190 #ifndef PRODUCT
5191   if (PrintIdealGraphLevel < 0) { // disabled by the user
5192     return false;
5193   }
5194 
5195   bool need = directive()->IGVPrintLevelOption >= level;
5196   if (need && !_igv_printer) {
5197     _igv_printer = IdealGraphPrinter::printer();
5198     _igv_printer->set_compile(this);
5199   }
5200   return need;
5201 #else
5202   return false;
5203 #endif
5204 }
5205 
5206 #ifndef PRODUCT
5207 IdealGraphPrinter* Compile::_debug_file_printer = nullptr;
5208 IdealGraphPrinter* Compile::_debug_network_printer = nullptr;
5209 
5210 // Called from debugger. Prints method to the default file with the default phase name.
5211 // This works regardless of any Ideal Graph Visualizer flags set or not.
5212 void igv_print() {
5213   Compile::current()->igv_print_method_to_file();
5214 }
5215 
5216 // Same as igv_print() above but with a specified phase name.
5217 void igv_print(const char* phase_name) {
5218   Compile::current()->igv_print_method_to_file(phase_name);
5219 }
5220 
5221 // Called from debugger. Prints method with the default phase name to the default network or the one specified with
5222 // the network flags for the Ideal Graph Visualizer, or to the default file depending on the 'network' argument.
5223 // This works regardless of any Ideal Graph Visualizer flags set or not.
5224 void igv_print(bool network) {
5225   if (network) {
5226     Compile::current()->igv_print_method_to_network();
5227   } else {
5228     Compile::current()->igv_print_method_to_file();
5229   }
5230 }
5231 
5232 // Same as igv_print(bool network) above but with a specified phase name.
5233 void igv_print(bool network, const char* phase_name) {
5234   if (network) {
5235     Compile::current()->igv_print_method_to_network(phase_name);
5236   } else {
5237     Compile::current()->igv_print_method_to_file(phase_name);
5238   }
5239 }
5240 
5241 // Called from debugger. Normal write to the default _printer. Only works if Ideal Graph Visualizer printing flags are set.
5242 void igv_print_default() {
5243   Compile::current()->print_method(PHASE_DEBUG, 0);
5244 }
5245 
5246 // Called from debugger, especially when replaying a trace in which the program state cannot be altered like with rr replay.
5247 // A method is appended to an existing default file with the default phase name. This means that igv_append() must follow
5248 // an earlier igv_print(*) call which sets up the file. This works regardless of any Ideal Graph Visualizer flags set or not.
5249 void igv_append() {
5250   Compile::current()->igv_print_method_to_file("Debug", true);
5251 }
5252 
5253 // Same as igv_append() above but with a specified phase name.
5254 void igv_append(const char* phase_name) {
5255   Compile::current()->igv_print_method_to_file(phase_name, true);
5256 }
5257 
5258 void Compile::igv_print_method_to_file(const char* phase_name, bool append) {
5259   const char* file_name = "custom_debug.xml";
5260   if (_debug_file_printer == nullptr) {
5261     _debug_file_printer = new IdealGraphPrinter(C, file_name, append);
5262   } else {
5263     _debug_file_printer->update_compiled_method(C->method());
5264   }
5265   tty->print_cr("Method %s to %s", append ? "appended" : "printed", file_name);
5266   _debug_file_printer->print(phase_name, (Node*)C->root());
5267 }
5268 
5269 void Compile::igv_print_method_to_network(const char* phase_name) {
5270   if (_debug_network_printer == nullptr) {
5271     _debug_network_printer = new IdealGraphPrinter(C);
5272   } else {
5273     _debug_network_printer->update_compiled_method(C->method());
5274   }
5275   tty->print_cr("Method printed over network stream to IGV");
5276   _debug_network_printer->print(phase_name, (Node*)C->root());
5277 }
5278 #endif
5279 
5280 Node* Compile::narrow_value(BasicType bt, Node* value, const Type* type, PhaseGVN* phase, bool transform_res) {
5281   if (type != nullptr && phase->type(value)->higher_equal(type)) {
5282     return value;
5283   }
5284   Node* result = nullptr;
5285   if (bt == T_BYTE) {
5286     result = phase->transform(new LShiftINode(value, phase->intcon(24)));
5287     result = new RShiftINode(result, phase->intcon(24));
5288   } else if (bt == T_BOOLEAN) {
5289     result = new AndINode(value, phase->intcon(0xFF));
5290   } else if (bt == T_CHAR) {
5291     result = new AndINode(value,phase->intcon(0xFFFF));
5292   } else {
5293     assert(bt == T_SHORT, "unexpected narrow type");
5294     result = phase->transform(new LShiftINode(value, phase->intcon(16)));
5295     result = new RShiftINode(result, phase->intcon(16));
5296   }
5297   if (transform_res) {
5298     result = phase->transform(result);
5299   }
5300   return result;
5301 }
5302