1 /*
   2  * Copyright (c) 1997, 2026, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "asm/macroAssembler.hpp"
  26 #include "asm/macroAssembler.inline.hpp"
  27 #include "ci/ciReplay.hpp"
  28 #include "classfile/javaClasses.hpp"
  29 #include "code/aotCodeCache.hpp"
  30 #include "code/exceptionHandlerTable.hpp"
  31 #include "code/nmethod.hpp"
  32 #include "compiler/compilationFailureInfo.hpp"
  33 #include "compiler/compilationMemoryStatistic.hpp"
  34 #include "compiler/compileBroker.hpp"
  35 #include "compiler/compileLog.hpp"
  36 #include "compiler/compiler_globals.hpp"
  37 #include "compiler/compilerDefinitions.hpp"
  38 #include "compiler/compilerOracle.hpp"
  39 #include "compiler/disassembler.hpp"
  40 #include "compiler/oopMap.hpp"
  41 #include "gc/shared/barrierSet.hpp"
  42 #include "gc/shared/c2/barrierSetC2.hpp"
  43 #include "jfr/jfrEvents.hpp"
  44 #include "jvm_io.h"
  45 #include "memory/allocation.hpp"
  46 #include "memory/arena.hpp"
  47 #include "memory/resourceArea.hpp"
  48 #include "opto/addnode.hpp"
  49 #include "opto/block.hpp"
  50 #include "opto/c2compiler.hpp"
  51 #include "opto/callGenerator.hpp"
  52 #include "opto/callnode.hpp"
  53 #include "opto/castnode.hpp"
  54 #include "opto/cfgnode.hpp"
  55 #include "opto/chaitin.hpp"
  56 #include "opto/compile.hpp"
  57 #include "opto/connode.hpp"
  58 #include "opto/convertnode.hpp"
  59 #include "opto/divnode.hpp"
  60 #include "opto/escape.hpp"
  61 #include "opto/idealGraphPrinter.hpp"
  62 #include "opto/locknode.hpp"
  63 #include "opto/loopnode.hpp"
  64 #include "opto/machnode.hpp"
  65 #include "opto/macro.hpp"
  66 #include "opto/matcher.hpp"
  67 #include "opto/mathexactnode.hpp"
  68 #include "opto/memnode.hpp"
  69 #include "opto/mulnode.hpp"
  70 #include "opto/narrowptrnode.hpp"
  71 #include "opto/node.hpp"
  72 #include "opto/opaquenode.hpp"
  73 #include "opto/opcodes.hpp"
  74 #include "opto/output.hpp"
  75 #include "opto/parse.hpp"
  76 #include "opto/phaseX.hpp"
  77 #include "opto/reachability.hpp"
  78 #include "opto/rootnode.hpp"
  79 #include "opto/runtime.hpp"
  80 #include "opto/stringopts.hpp"
  81 #include "opto/type.hpp"
  82 #include "opto/vector.hpp"
  83 #include "opto/vectornode.hpp"
  84 #include "runtime/globals_extension.hpp"
  85 #include "runtime/sharedRuntime.hpp"
  86 #include "runtime/signature.hpp"
  87 #include "runtime/stubRoutines.hpp"
  88 #include "runtime/timer.hpp"
  89 #include "utilities/align.hpp"
  90 #include "utilities/copy.hpp"
  91 #include "utilities/hashTable.hpp"
  92 #include "utilities/macros.hpp"
  93 
  94 // -------------------- Compile::mach_constant_base_node -----------------------
  95 // Constant table base node singleton.
  96 MachConstantBaseNode* Compile::mach_constant_base_node() {
  97   if (_mach_constant_base_node == nullptr) {
  98     _mach_constant_base_node = new MachConstantBaseNode();
  99     _mach_constant_base_node->add_req(C->root());
 100   }
 101   return _mach_constant_base_node;
 102 }
 103 
 104 
 105 /// Support for intrinsics.
 106 
 107 // Return the index at which m must be inserted (or already exists).
 108 // The sort order is by the address of the ciMethod, with is_virtual as minor key.
 109 class IntrinsicDescPair {
 110  private:
 111   ciMethod* _m;
 112   bool _is_virtual;
 113  public:
 114   IntrinsicDescPair(ciMethod* m, bool is_virtual) : _m(m), _is_virtual(is_virtual) {}
 115   static int compare(IntrinsicDescPair* const& key, CallGenerator* const& elt) {
 116     ciMethod* m= elt->method();
 117     ciMethod* key_m = key->_m;
 118     if (key_m < m)      return -1;
 119     else if (key_m > m) return 1;
 120     else {
 121       bool is_virtual = elt->is_virtual();
 122       bool key_virtual = key->_is_virtual;
 123       if (key_virtual < is_virtual)      return -1;
 124       else if (key_virtual > is_virtual) return 1;
 125       else                               return 0;
 126     }
 127   }
 128 };
 129 int Compile::intrinsic_insertion_index(ciMethod* m, bool is_virtual, bool& found) {
 130 #ifdef ASSERT
 131   for (int i = 1; i < _intrinsics.length(); i++) {
 132     CallGenerator* cg1 = _intrinsics.at(i-1);
 133     CallGenerator* cg2 = _intrinsics.at(i);
 134     assert(cg1->method() != cg2->method()
 135            ? cg1->method()     < cg2->method()
 136            : cg1->is_virtual() < cg2->is_virtual(),
 137            "compiler intrinsics list must stay sorted");
 138   }
 139 #endif
 140   IntrinsicDescPair pair(m, is_virtual);
 141   return _intrinsics.find_sorted<IntrinsicDescPair*, IntrinsicDescPair::compare>(&pair, found);
 142 }
 143 
 144 void Compile::register_intrinsic(CallGenerator* cg) {
 145   bool found = false;
 146   int index = intrinsic_insertion_index(cg->method(), cg->is_virtual(), found);
 147   assert(!found, "registering twice");
 148   _intrinsics.insert_before(index, cg);
 149   assert(find_intrinsic(cg->method(), cg->is_virtual()) == cg, "registration worked");
 150 }
 151 
 152 CallGenerator* Compile::find_intrinsic(ciMethod* m, bool is_virtual) {
 153   assert(m->is_loaded(), "don't try this on unloaded methods");
 154   if (_intrinsics.length() > 0) {
 155     bool found = false;
 156     int index = intrinsic_insertion_index(m, is_virtual, found);
 157      if (found) {
 158       return _intrinsics.at(index);
 159     }
 160   }
 161   // Lazily create intrinsics for intrinsic IDs well-known in the runtime.
 162   if (m->intrinsic_id() != vmIntrinsics::_none &&
 163       m->intrinsic_id() <= vmIntrinsics::LAST_COMPILER_INLINE) {
 164     CallGenerator* cg = make_vm_intrinsic(m, is_virtual);
 165     if (cg != nullptr) {
 166       // Save it for next time:
 167       register_intrinsic(cg);
 168       return cg;
 169     } else {
 170       gather_intrinsic_statistics(m->intrinsic_id(), is_virtual, _intrinsic_disabled);
 171     }
 172   }
 173   return nullptr;
 174 }
 175 
 176 // Compile::make_vm_intrinsic is defined in library_call.cpp.
 177 
 178 #ifndef PRODUCT
 179 // statistics gathering...
 180 
 181 juint  Compile::_intrinsic_hist_count[vmIntrinsics::number_of_intrinsics()] = {0};
 182 jubyte Compile::_intrinsic_hist_flags[vmIntrinsics::number_of_intrinsics()] = {0};
 183 
 184 inline int as_int(vmIntrinsics::ID id) {
 185   return vmIntrinsics::as_int(id);
 186 }
 187 
 188 bool Compile::gather_intrinsic_statistics(vmIntrinsics::ID id, bool is_virtual, int flags) {
 189   assert(id > vmIntrinsics::_none && id < vmIntrinsics::ID_LIMIT, "oob");
 190   int oflags = _intrinsic_hist_flags[as_int(id)];
 191   assert(flags != 0, "what happened?");
 192   if (is_virtual) {
 193     flags |= _intrinsic_virtual;
 194   }
 195   bool changed = (flags != oflags);
 196   if ((flags & _intrinsic_worked) != 0) {
 197     juint count = (_intrinsic_hist_count[as_int(id)] += 1);
 198     if (count == 1) {
 199       changed = true;           // first time
 200     }
 201     // increment the overall count also:
 202     _intrinsic_hist_count[as_int(vmIntrinsics::_none)] += 1;
 203   }
 204   if (changed) {
 205     if (((oflags ^ flags) & _intrinsic_virtual) != 0) {
 206       // Something changed about the intrinsic's virtuality.
 207       if ((flags & _intrinsic_virtual) != 0) {
 208         // This is the first use of this intrinsic as a virtual call.
 209         if (oflags != 0) {
 210           // We already saw it as a non-virtual, so note both cases.
 211           flags |= _intrinsic_both;
 212         }
 213       } else if ((oflags & _intrinsic_both) == 0) {
 214         // This is the first use of this intrinsic as a non-virtual
 215         flags |= _intrinsic_both;
 216       }
 217     }
 218     _intrinsic_hist_flags[as_int(id)] = (jubyte) (oflags | flags);
 219   }
 220   // update the overall flags also:
 221   _intrinsic_hist_flags[as_int(vmIntrinsics::_none)] |= (jubyte) flags;
 222   return changed;
 223 }
 224 
 225 static char* format_flags(int flags, char* buf) {
 226   buf[0] = 0;
 227   if ((flags & Compile::_intrinsic_worked) != 0)    strcat(buf, ",worked");
 228   if ((flags & Compile::_intrinsic_failed) != 0)    strcat(buf, ",failed");
 229   if ((flags & Compile::_intrinsic_disabled) != 0)  strcat(buf, ",disabled");
 230   if ((flags & Compile::_intrinsic_virtual) != 0)   strcat(buf, ",virtual");
 231   if ((flags & Compile::_intrinsic_both) != 0)      strcat(buf, ",nonvirtual");
 232   if (buf[0] == 0)  strcat(buf, ",");
 233   assert(buf[0] == ',', "must be");
 234   return &buf[1];
 235 }
 236 
 237 void Compile::print_intrinsic_statistics() {
 238   char flagsbuf[100];
 239   ttyLocker ttyl;
 240   if (xtty != nullptr)  xtty->head("statistics type='intrinsic'");
 241   tty->print_cr("Compiler intrinsic usage:");
 242   juint total = _intrinsic_hist_count[as_int(vmIntrinsics::_none)];
 243   if (total == 0)  total = 1;  // avoid div0 in case of no successes
 244   #define PRINT_STAT_LINE(name, c, f) \
 245     tty->print_cr("  %4d (%4.1f%%) %s (%s)", (int)(c), ((c) * 100.0) / total, name, f);
 246   for (auto id : EnumRange<vmIntrinsicID>{}) {
 247     int   flags = _intrinsic_hist_flags[as_int(id)];
 248     juint count = _intrinsic_hist_count[as_int(id)];
 249     if ((flags | count) != 0) {
 250       PRINT_STAT_LINE(vmIntrinsics::name_at(id), count, format_flags(flags, flagsbuf));
 251     }
 252   }
 253   PRINT_STAT_LINE("total", total, format_flags(_intrinsic_hist_flags[as_int(vmIntrinsics::_none)], flagsbuf));
 254   if (xtty != nullptr)  xtty->tail("statistics");
 255 }
 256 
 257 void Compile::print_statistics() {
 258   { ttyLocker ttyl;
 259     if (xtty != nullptr)  xtty->head("statistics type='opto'");
 260     Parse::print_statistics();
 261     PhaseStringOpts::print_statistics();
 262     PhaseCCP::print_statistics();
 263     PhaseRegAlloc::print_statistics();
 264     PhaseOutput::print_statistics();
 265     PhasePeephole::print_statistics();
 266     PhaseIdealLoop::print_statistics();
 267     ConnectionGraph::print_statistics();
 268     PhaseMacroExpand::print_statistics();
 269     if (xtty != nullptr)  xtty->tail("statistics");
 270   }
 271   if (_intrinsic_hist_flags[as_int(vmIntrinsics::_none)] != 0) {
 272     // put this under its own <statistics> element.
 273     print_intrinsic_statistics();
 274   }
 275 }
 276 #endif //PRODUCT
 277 
 278 void Compile::gvn_replace_by(Node* n, Node* nn) {
 279   for (DUIterator_Last imin, i = n->last_outs(imin); i >= imin; ) {
 280     Node* use = n->last_out(i);
 281     bool is_in_table = initial_gvn()->hash_delete(use);
 282     uint uses_found = 0;
 283     for (uint j = 0; j < use->len(); j++) {
 284       if (use->in(j) == n) {
 285         if (j < use->req())
 286           use->set_req(j, nn);
 287         else
 288           use->set_prec(j, nn);
 289         uses_found++;
 290       }
 291     }
 292     if (is_in_table) {
 293       // reinsert into table
 294       initial_gvn()->hash_find_insert(use);
 295     }
 296     record_for_igvn(use);
 297     PhaseIterGVN::add_users_of_use_to_worklist(nn, use, *_igvn_worklist);
 298     i -= uses_found;    // we deleted 1 or more copies of this edge
 299   }
 300 }
 301 
 302 
 303 // Identify all nodes that are reachable from below, useful.
 304 // Use breadth-first pass that records state in a Unique_Node_List,
 305 // recursive traversal is slower.
 306 void Compile::identify_useful_nodes(Unique_Node_List &useful) {
 307   int estimated_worklist_size = live_nodes();
 308   useful.map( estimated_worklist_size, nullptr );  // preallocate space
 309 
 310   // Initialize worklist
 311   if (root() != nullptr)  { useful.push(root()); }
 312   // If 'top' is cached, declare it useful to preserve cached node
 313   if (cached_top_node())  { useful.push(cached_top_node()); }
 314 
 315   // Push all useful nodes onto the list, breadthfirst
 316   for( uint next = 0; next < useful.size(); ++next ) {
 317     assert( next < unique(), "Unique useful nodes < total nodes");
 318     Node *n  = useful.at(next);
 319     uint max = n->len();
 320     for( uint i = 0; i < max; ++i ) {
 321       Node *m = n->in(i);
 322       if (not_a_node(m))  continue;
 323       useful.push(m);
 324     }
 325   }
 326 }
 327 
 328 // Update dead_node_list with any missing dead nodes using useful
 329 // list. Consider all non-useful nodes to be useless i.e., dead nodes.
 330 void Compile::update_dead_node_list(Unique_Node_List &useful) {
 331   uint max_idx = unique();
 332   VectorSet& useful_node_set = useful.member_set();
 333 
 334   for (uint node_idx = 0; node_idx < max_idx; node_idx++) {
 335     // If node with index node_idx is not in useful set,
 336     // mark it as dead in dead node list.
 337     if (!useful_node_set.test(node_idx)) {
 338       record_dead_node(node_idx);
 339     }
 340   }
 341 }
 342 
 343 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Unique_Node_List &useful) {
 344   int shift = 0;
 345   for (int i = 0; i < inlines->length(); i++) {
 346     CallGenerator* cg = inlines->at(i);
 347     if (useful.member(cg->call_node())) {
 348       if (shift > 0) {
 349         inlines->at_put(i - shift, cg);
 350       }
 351     } else {
 352       shift++; // skip over the dead element
 353     }
 354   }
 355   if (shift > 0) {
 356     inlines->trunc_to(inlines->length() - shift); // remove last elements from compacted array
 357   }
 358 }
 359 
 360 void Compile::remove_useless_late_inlines(GrowableArray<CallGenerator*>* inlines, Node* dead) {
 361   assert(dead != nullptr && dead->is_Call(), "sanity");
 362   int found = 0;
 363   for (int i = 0; i < inlines->length(); i++) {
 364     if (inlines->at(i)->call_node() == dead) {
 365       inlines->remove_at(i);
 366       found++;
 367       NOT_DEBUG( break; ) // elements are unique, so exit early
 368     }
 369   }
 370   assert(found <= 1, "not unique");
 371 }
 372 
 373 template<typename N, ENABLE_IF_SDEFN(std::is_base_of<Node, N>::value)>
 374 void Compile::remove_useless_nodes(GrowableArray<N*>& node_list, Unique_Node_List& useful) {
 375   for (int i = node_list.length() - 1; i >= 0; i--) {
 376     N* node = node_list.at(i);
 377     if (!useful.member(node)) {
 378       node_list.delete_at(i); // replaces i-th with last element which is known to be useful (already processed)
 379     }
 380   }
 381 }
 382 
 383 void Compile::remove_useless_node(Node* dead) {
 384   remove_modified_node(dead);
 385 
 386   // Constant node that has no out-edges and has only one in-edge from
 387   // root is usually dead. However, sometimes reshaping walk makes
 388   // it reachable by adding use edges. So, we will NOT count Con nodes
 389   // as dead to be conservative about the dead node count at any
 390   // given time.
 391   if (!dead->is_Con()) {
 392     record_dead_node(dead->_idx);
 393   }
 394   if (dead->is_macro()) {
 395     remove_macro_node(dead);
 396   }
 397   if (dead->is_expensive()) {
 398     remove_expensive_node(dead);
 399   }
 400   if (dead->is_ReachabilityFence()) {
 401     remove_reachability_fence(dead->as_ReachabilityFence());
 402   }
 403   if (dead->is_OpaqueTemplateAssertionPredicate()) {
 404     remove_template_assertion_predicate_opaque(dead->as_OpaqueTemplateAssertionPredicate());
 405   }
 406   if (dead->is_ParsePredicate()) {
 407     remove_parse_predicate(dead->as_ParsePredicate());
 408   }
 409   if (dead->for_post_loop_opts_igvn()) {
 410     remove_from_post_loop_opts_igvn(dead);
 411   }
 412   if (dead->for_merge_stores_igvn()) {
 413     remove_from_merge_stores_igvn(dead);
 414   }
 415   if (dead->is_Call()) {
 416     remove_useless_late_inlines(                &_late_inlines, dead);
 417     remove_useless_late_inlines(         &_string_late_inlines, dead);
 418     remove_useless_late_inlines(         &_boxing_late_inlines, dead);
 419     remove_useless_late_inlines(&_vector_reboxing_late_inlines, dead);
 420 
 421     if (dead->is_CallStaticJava()) {
 422       remove_unstable_if_trap(dead->as_CallStaticJava(), false);
 423     }
 424   }
 425   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
 426   bs->unregister_potential_barrier_node(dead);
 427 }
 428 
 429 // Disconnect all useless nodes by disconnecting those at the boundary.
 430 void Compile::disconnect_useless_nodes(Unique_Node_List& useful, Unique_Node_List& worklist, const Unique_Node_List* root_and_safepoints) {
 431   uint next = 0;
 432   while (next < useful.size()) {
 433     Node *n = useful.at(next++);
 434     if (n->is_SafePoint()) {
 435       // We're done with a parsing phase. Replaced nodes are not valid
 436       // beyond that point.
 437       n->as_SafePoint()->delete_replaced_nodes();
 438     }
 439     // Use raw traversal of out edges since this code removes out edges
 440     int max = n->outcnt();
 441     for (int j = 0; j < max; ++j) {
 442       Node* child = n->raw_out(j);
 443       if (!useful.member(child)) {
 444         assert(!child->is_top() || child != top(),
 445                "If top is cached in Compile object it is in useful list");
 446         // Only need to remove this out-edge to the useless node
 447         n->raw_del_out(j);
 448         --j;
 449         --max;
 450         if (child->is_data_proj_of_pure_function(n)) {
 451           worklist.push(n);
 452         }
 453       }
 454     }
 455     if (n->outcnt() == 1 && n->has_special_unique_user()) {
 456       assert(useful.member(n->unique_out()), "do not push a useless node");
 457       worklist.push(n->unique_out());
 458     }
 459   }
 460 
 461   remove_useless_nodes(_macro_nodes,        useful); // remove useless macro nodes
 462   remove_useless_nodes(_parse_predicates,   useful); // remove useless Parse Predicate nodes
 463   // Remove useless Template Assertion Predicate opaque nodes
 464   remove_useless_nodes(_template_assertion_predicate_opaques, useful);
 465   remove_useless_nodes(_expensive_nodes,    useful); // remove useless expensive nodes
 466   remove_useless_nodes(_reachability_fences, useful); // remove useless node recorded for post loop opts IGVN pass
 467   remove_useless_nodes(_for_post_loop_igvn, useful); // remove useless node recorded for post loop opts IGVN pass
 468   remove_useless_nodes(_for_merge_stores_igvn, useful); // remove useless node recorded for merge stores IGVN pass
 469   remove_useless_unstable_if_traps(useful);          // remove useless unstable_if traps
 470   remove_useless_coarsened_locks(useful);            // remove useless coarsened locks nodes
 471 #ifdef ASSERT
 472   if (_modified_nodes != nullptr) {
 473     _modified_nodes->remove_useless_nodes(useful.member_set());
 474   }
 475 #endif
 476 
 477   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
 478   bs->eliminate_useless_gc_barriers(useful, this);
 479   // clean up the late inline lists
 480   remove_useless_late_inlines(                &_late_inlines, useful);
 481   remove_useless_late_inlines(         &_string_late_inlines, useful);
 482   remove_useless_late_inlines(         &_boxing_late_inlines, useful);
 483   remove_useless_late_inlines(&_vector_reboxing_late_inlines, useful);
 484   DEBUG_ONLY(verify_graph_edges(true /*check for no_dead_code*/, root_and_safepoints);)
 485 }
 486 
 487 // ============================================================================
 488 //------------------------------CompileWrapper---------------------------------
 489 class CompileWrapper : public StackObj {
 490   Compile *const _compile;
 491  public:
 492   CompileWrapper(Compile* compile);
 493 
 494   ~CompileWrapper();
 495 };
 496 
 497 CompileWrapper::CompileWrapper(Compile* compile) : _compile(compile) {
 498   // the Compile* pointer is stored in the current ciEnv:
 499   ciEnv* env = compile->env();
 500   assert(env == ciEnv::current(), "must already be a ciEnv active");
 501   assert(env->compiler_data() == nullptr, "compile already active?");
 502   env->set_compiler_data(compile);
 503   assert(compile == Compile::current(), "sanity");
 504 
 505   compile->set_type_dict(nullptr);
 506   compile->set_clone_map(new Dict(cmpkey, hashkey, _compile->comp_arena()));
 507   compile->clone_map().set_clone_idx(0);
 508   compile->set_type_last_size(0);
 509   compile->set_last_tf(nullptr, nullptr);
 510   compile->set_indexSet_arena(nullptr);
 511   compile->set_indexSet_free_block_list(nullptr);
 512   compile->init_type_arena();
 513   Type::Initialize(compile);
 514   _compile->begin_method();
 515   _compile->clone_map().set_debug(_compile->has_method() && _compile->directive()->CloneMapDebugOption);
 516 }
 517 CompileWrapper::~CompileWrapper() {
 518   // simulate crash during compilation
 519   assert(CICrashAt < 0 || _compile->compile_id() != CICrashAt, "just as planned");
 520 
 521   _compile->end_method();
 522   _compile->env()->set_compiler_data(nullptr);
 523 }
 524 
 525 
 526 //----------------------------print_compile_messages---------------------------
 527 void Compile::print_compile_messages() {
 528 #ifndef PRODUCT
 529   // Check if recompiling
 530   if (!subsume_loads() && PrintOpto) {
 531     // Recompiling without allowing machine instructions to subsume loads
 532     tty->print_cr("*********************************************************");
 533     tty->print_cr("** Bailout: Recompile without subsuming loads          **");
 534     tty->print_cr("*********************************************************");
 535   }
 536   if ((do_escape_analysis() != DoEscapeAnalysis) && PrintOpto) {
 537     // Recompiling without escape analysis
 538     tty->print_cr("*********************************************************");
 539     tty->print_cr("** Bailout: Recompile without escape analysis          **");
 540     tty->print_cr("*********************************************************");
 541   }
 542   if (do_iterative_escape_analysis() != DoEscapeAnalysis && PrintOpto) {
 543     // Recompiling without iterative escape analysis
 544     tty->print_cr("*********************************************************");
 545     tty->print_cr("** Bailout: Recompile without iterative escape analysis**");
 546     tty->print_cr("*********************************************************");
 547   }
 548   if (do_reduce_allocation_merges() != ReduceAllocationMerges && PrintOpto) {
 549     // Recompiling without reducing allocation merges
 550     tty->print_cr("*********************************************************");
 551     tty->print_cr("** Bailout: Recompile without reduce allocation merges **");
 552     tty->print_cr("*********************************************************");
 553   }
 554   if ((eliminate_boxing() != EliminateAutoBox) && PrintOpto) {
 555     // Recompiling without boxing elimination
 556     tty->print_cr("*********************************************************");
 557     tty->print_cr("** Bailout: Recompile without boxing elimination       **");
 558     tty->print_cr("*********************************************************");
 559   }
 560   if ((do_locks_coarsening() != EliminateLocks) && PrintOpto) {
 561     // Recompiling without locks coarsening
 562     tty->print_cr("*********************************************************");
 563     tty->print_cr("** Bailout: Recompile without locks coarsening         **");
 564     tty->print_cr("*********************************************************");
 565   }
 566   if (env()->break_at_compile()) {
 567     // Open the debugger when compiling this method.
 568     tty->print("### Breaking when compiling: ");
 569     method()->print_short_name();
 570     tty->cr();
 571     BREAKPOINT;
 572   }
 573 
 574   if( PrintOpto ) {
 575     if (is_osr_compilation()) {
 576       tty->print("[OSR]%3d", _compile_id);
 577     } else {
 578       tty->print("%3d", _compile_id);
 579     }
 580   }
 581 #endif
 582 }
 583 
 584 #ifndef PRODUCT
 585 void Compile::print_phase(const char* phase_name) {
 586   tty->print_cr("%u.\t%s", ++_phase_counter, phase_name);
 587 }
 588 
 589 void Compile::print_ideal_ir(const char* compile_phase_name) const {
 590   // keep the following output all in one block
 591   // This output goes directly to the tty, not the compiler log.
 592   // To enable tools to match it up with the compilation activity,
 593   // be sure to tag this tty output with the compile ID.
 594 
 595   // Node dumping can cause a safepoint, which can break the tty lock.
 596   // Buffer all node dumps, so that all safepoints happen before we lock.
 597   ResourceMark rm;
 598   stringStream ss;
 599 
 600   if (_output == nullptr) {
 601     ss.print_cr("AFTER: %s", compile_phase_name);
 602     // Print out all nodes in ascending order of index.
 603     // It is important that we traverse both inputs and outputs of nodes,
 604     // so that we reach all nodes that are connected to Root.
 605     root()->dump_bfs(MaxNodeLimit, nullptr, "-+S$", &ss);
 606   } else {
 607     // Dump the node blockwise if we have a scheduling
 608     _output->print_scheduling(&ss);
 609   }
 610 
 611   // Check that the lock is not broken by a safepoint.
 612   NoSafepointVerifier nsv;
 613   ttyLocker ttyl;
 614   if (xtty != nullptr) {
 615     xtty->head("ideal compile_id='%d'%s compile_phase='%s'",
 616                compile_id(),
 617                is_osr_compilation() ? " compile_kind='osr'" : "",
 618                compile_phase_name);
 619   }
 620 
 621   tty->print("%s", ss.as_string());
 622 
 623   if (xtty != nullptr) {
 624     xtty->tail("ideal");
 625   }
 626 }
 627 #endif
 628 
 629 // ============================================================================
 630 //------------------------------Compile standard-------------------------------
 631 
 632 // Compile a method.  entry_bci is -1 for normal compilations and indicates
 633 // the continuation bci for on stack replacement.
 634 
 635 
 636 Compile::Compile(ciEnv* ci_env, ciMethod* target, int osr_bci,
 637                  Options options, DirectiveSet* directive)
 638     : Phase(Compiler),
 639       _compile_id(ci_env->compile_id()),
 640       _options(options),
 641       _method(target),
 642       _entry_bci(osr_bci),
 643       _ilt(nullptr),
 644       _stub_function(nullptr),
 645       _stub_name(nullptr),
 646       _stub_id(StubId::NO_STUBID),
 647       _stub_entry_point(nullptr),
 648       _max_node_limit(MaxNodeLimit),
 649       _post_loop_opts_phase(false),
 650       _merge_stores_phase(false),
 651       _allow_macro_nodes(true),
 652       _inlining_progress(false),
 653       _inlining_incrementally(false),
 654       _do_cleanup(false),
 655       _has_reserved_stack_access(target->has_reserved_stack_access()),
 656 #ifndef PRODUCT
 657       _igv_idx(0),
 658       _trace_opto_output(directive->TraceOptoOutputOption),
 659 #endif
 660       _clinit_barrier_on_entry(false),
 661       _stress_seed(0),
 662       _comp_arena(mtCompiler, Arena::Tag::tag_comp),
 663       _barrier_set_state(BarrierSet::barrier_set()->barrier_set_c2()->create_barrier_state(comp_arena())),
 664       _env(ci_env),
 665       _directive(directive),
 666       _log(ci_env->log()),
 667       _first_failure_details(nullptr),
 668       _intrinsics(comp_arena(), 0, 0, nullptr),
 669       _macro_nodes(comp_arena(), 8, 0, nullptr),
 670       _parse_predicates(comp_arena(), 8, 0, nullptr),
 671       _template_assertion_predicate_opaques(comp_arena(), 8, 0, nullptr),
 672       _expensive_nodes(comp_arena(), 8, 0, nullptr),
 673       _reachability_fences(comp_arena(), 8, 0, nullptr),
 674       _for_post_loop_igvn(comp_arena(), 8, 0, nullptr),
 675       _for_merge_stores_igvn(comp_arena(), 8, 0, nullptr),
 676       _unstable_if_traps(comp_arena(), 8, 0, nullptr),
 677       _coarsened_locks(comp_arena(), 8, 0, nullptr),
 678       _congraph(nullptr),
 679       NOT_PRODUCT(_igv_printer(nullptr) COMMA)
 680       _unique(0),
 681       _dead_node_count(0),
 682       _dead_node_list(comp_arena()),
 683       _node_arena_one(mtCompiler, Arena::Tag::tag_node),
 684       _node_arena_two(mtCompiler, Arena::Tag::tag_node),
 685       _node_arena(&_node_arena_one),
 686       _mach_constant_base_node(nullptr),
 687       _Compile_types(mtCompiler, Arena::Tag::tag_type),
 688       _initial_gvn(nullptr),
 689       _igvn_worklist(nullptr),
 690       _types(nullptr),
 691       _node_hash(nullptr),
 692       _late_inlines(comp_arena(), 2, 0, nullptr),
 693       _string_late_inlines(comp_arena(), 2, 0, nullptr),
 694       _boxing_late_inlines(comp_arena(), 2, 0, nullptr),
 695       _vector_reboxing_late_inlines(comp_arena(), 2, 0, nullptr),
 696       _late_inlines_pos(0),
 697       _has_mh_late_inlines(false),
 698       _oom(false),
 699       _replay_inline_data(nullptr),
 700       _inline_printer(this),
 701       _java_calls(0),
 702       _inner_loops(0),
 703       _FIRST_STACK_mask(comp_arena()),
 704       _interpreter_frame_size(0),
 705       _regmask_arena(mtCompiler, Arena::Tag::tag_regmask),
 706       _output(nullptr)
 707 #ifndef PRODUCT
 708       ,
 709       _in_dump_cnt(0)
 710 #endif
 711 {
 712   C = this;
 713   CompileWrapper cw(this);
 714 
 715   TraceTime t1("Total compilation time", &_t_totalCompilation, CITime, CITimeVerbose);
 716   TraceTime t2(nullptr, &_t_methodCompilation, CITime, false);
 717 
 718 #if defined(SUPPORT_ASSEMBLY) || defined(SUPPORT_ABSTRACT_ASSEMBLY)
 719   bool print_opto_assembly = directive->PrintOptoAssemblyOption;
 720   // We can always print a disassembly, either abstract (hex dump) or
 721   // with the help of a suitable hsdis library. Thus, we should not
 722   // couple print_assembly and print_opto_assembly controls.
 723   // But: always print opto and regular assembly on compile command 'print'.
 724   bool print_assembly = directive->PrintAssemblyOption;
 725   set_print_assembly(print_opto_assembly || print_assembly);
 726 #else
 727   set_print_assembly(false); // must initialize.
 728 #endif
 729 
 730 #ifndef PRODUCT
 731   set_parsed_irreducible_loop(false);
 732 #endif
 733 
 734   if (directive->ReplayInlineOption) {
 735     _replay_inline_data = ciReplay::load_inline_data(method(), entry_bci(), ci_env->comp_level());
 736   }
 737   set_print_inlining(directive->PrintInliningOption || PrintOptoInlining);
 738   set_print_intrinsics(directive->PrintIntrinsicsOption);
 739   set_has_irreducible_loop(true); // conservative until build_loop_tree() reset it
 740 
 741   if (ProfileTraps) {
 742     // Make sure the method being compiled gets its own MDO,
 743     // so we can at least track the decompile_count().
 744     method()->ensure_method_data();
 745   }
 746 
 747   if (StressLCM || StressGCM || StressIGVN || StressCCP ||
 748       StressIncrementalInlining || StressMacroExpansion ||
 749       StressMacroElimination || StressUnstableIfTraps ||
 750       StressBailout || StressLoopPeeling || StressCountedLoop) {
 751     initialize_stress_seed(directive);
 752   }
 753 
 754   Init(/*do_aliasing=*/ true);
 755 
 756   print_compile_messages();
 757 
 758   _ilt = InlineTree::build_inline_tree_root();
 759 
 760   // Even if NO memory addresses are used, MergeMem nodes must have at least 1 slice
 761   assert(num_alias_types() >= AliasIdxRaw, "");
 762 
 763 #define MINIMUM_NODE_HASH  1023
 764 
 765   // GVN that will be run immediately on new nodes
 766   uint estimated_size = method()->code_size()*4+64;
 767   estimated_size = (estimated_size < MINIMUM_NODE_HASH ? MINIMUM_NODE_HASH : estimated_size);
 768   _igvn_worklist = new (comp_arena()) Unique_Node_List(comp_arena());
 769   _types = new (comp_arena()) Type_Array(comp_arena());
 770   _node_hash = new (comp_arena()) NodeHash(comp_arena(), estimated_size);
 771   PhaseGVN gvn;
 772   set_initial_gvn(&gvn);
 773 
 774   { // Scope for timing the parser
 775     TracePhase tp(_t_parser);
 776 
 777     // Put top into the hash table ASAP.
 778     initial_gvn()->transform(top());
 779 
 780     // Set up tf(), start(), and find a CallGenerator.
 781     CallGenerator* cg = nullptr;
 782     if (is_osr_compilation()) {
 783       const TypeTuple *domain = StartOSRNode::osr_domain();
 784       const TypeTuple *range = TypeTuple::make_range(method()->signature());
 785       init_tf(TypeFunc::make(domain, range));
 786       StartNode* s = new StartOSRNode(root(), domain);
 787       initial_gvn()->set_type_bottom(s);
 788       verify_start(s);
 789       cg = CallGenerator::for_osr(method(), entry_bci());
 790     } else {
 791       // Normal case.
 792       init_tf(TypeFunc::make(method()));
 793       StartNode* s = new StartNode(root(), tf()->domain());
 794       initial_gvn()->set_type_bottom(s);
 795       verify_start(s);
 796       float past_uses = method()->interpreter_invocation_count();
 797       float expected_uses = past_uses;
 798       cg = CallGenerator::for_inline(method(), expected_uses);
 799     }
 800     if (failing())  return;
 801     if (cg == nullptr) {
 802       const char* reason = InlineTree::check_can_parse(method());
 803       assert(reason != nullptr, "expect reason for parse failure");
 804       stringStream ss;
 805       ss.print("cannot parse method: %s", reason);
 806       record_method_not_compilable(ss.as_string());
 807       return;
 808     }
 809 
 810     gvn.set_type(root(), root()->bottom_type());
 811 
 812     JVMState* jvms = build_start_state(start(), tf());
 813     if ((jvms = cg->generate(jvms)) == nullptr) {
 814       assert(failure_reason() != nullptr, "expect reason for parse failure");
 815       stringStream ss;
 816       ss.print("method parse failed: %s", failure_reason());
 817       record_method_not_compilable(ss.as_string() DEBUG_ONLY(COMMA true));
 818       return;
 819     }
 820     GraphKit kit(jvms);
 821 
 822     if (!kit.stopped()) {
 823       // Accept return values, and transfer control we know not where.
 824       // This is done by a special, unique ReturnNode bound to root.
 825       return_values(kit.jvms());
 826     }
 827 
 828     if (kit.has_exceptions()) {
 829       // Any exceptions that escape from this call must be rethrown
 830       // to whatever caller is dynamically above us on the stack.
 831       // This is done by a special, unique RethrowNode bound to root.
 832       rethrow_exceptions(kit.transfer_exceptions_into_jvms());
 833     }
 834 
 835     assert(IncrementalInline || (_late_inlines.length() == 0 && !has_mh_late_inlines()), "incremental inlining is off");
 836 
 837     if (_late_inlines.length() == 0 && !has_mh_late_inlines() && !failing() && has_stringbuilder()) {
 838       inline_string_calls(true);
 839     }
 840 
 841     if (failing())  return;
 842 
 843     // Remove clutter produced by parsing.
 844     if (!failing()) {
 845       ResourceMark rm;
 846       PhaseRemoveUseless pru(initial_gvn(), *igvn_worklist());
 847     }
 848   }
 849 
 850   // Note:  Large methods are capped off in do_one_bytecode().
 851   if (failing())  return;
 852 
 853   // After parsing, node notes are no longer automagic.
 854   // They must be propagated by register_new_node_with_optimizer(),
 855   // clone(), or the like.
 856   set_default_node_notes(nullptr);
 857 
 858 #ifndef PRODUCT
 859   if (should_print_igv(1)) {
 860     _igv_printer->print_inlining();
 861   }
 862 #endif
 863 
 864   if (failing())  return;
 865   NOT_PRODUCT( verify_graph_edges(); )
 866 
 867   // Now optimize
 868   Optimize();
 869   if (failing())  return;
 870   NOT_PRODUCT( verify_graph_edges(); )
 871 
 872 #ifndef PRODUCT
 873   if (should_print_ideal()) {
 874     print_ideal_ir("PrintIdeal");
 875   }
 876 #endif
 877 
 878 #ifdef ASSERT
 879   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
 880   bs->verify_gc_barriers(this, BarrierSetC2::BeforeCodeGen);
 881 #endif
 882 
 883   // Dump compilation data to replay it.
 884   if (directive->DumpReplayOption) {
 885     env()->dump_replay_data(_compile_id);
 886   }
 887   if (directive->DumpInlineOption && (ilt() != nullptr)) {
 888     env()->dump_inline_data(_compile_id);
 889   }
 890 
 891   // Now that we know the size of all the monitors we can add a fixed slot
 892   // for the original deopt pc.
 893   int next_slot = fixed_slots() + (sizeof(address) / VMRegImpl::stack_slot_size);
 894   set_fixed_slots(next_slot);
 895 
 896   // Compute when to use implicit null checks. Used by matching trap based
 897   // nodes and NullCheck optimization.
 898   set_allowed_deopt_reasons();
 899 
 900   // Now generate code
 901   Code_Gen();
 902 }
 903 
 904 //------------------------------Compile----------------------------------------
 905 // Compile a runtime stub
 906 Compile::Compile(ciEnv* ci_env,
 907                  TypeFunc_generator generator,
 908                  address stub_function,
 909                  const char* stub_name,
 910                  StubId stub_id,
 911                  int is_fancy_jump,
 912                  bool pass_tls,
 913                  bool return_pc,
 914                  DirectiveSet* directive)
 915     : Phase(Compiler),
 916       _compile_id(0),
 917       _options(Options::for_runtime_stub()),
 918       _method(nullptr),
 919       _entry_bci(InvocationEntryBci),
 920       _stub_function(stub_function),
 921       _stub_name(stub_name),
 922       _stub_id(stub_id),
 923       _stub_entry_point(nullptr),
 924       _max_node_limit(MaxNodeLimit),
 925       _post_loop_opts_phase(false),
 926       _merge_stores_phase(false),
 927       _allow_macro_nodes(true),
 928       _inlining_progress(false),
 929       _inlining_incrementally(false),
 930       _has_reserved_stack_access(false),
 931 #ifndef PRODUCT
 932       _igv_idx(0),
 933       _trace_opto_output(directive->TraceOptoOutputOption),
 934 #endif
 935       _clinit_barrier_on_entry(false),
 936       _stress_seed(0),
 937       _comp_arena(mtCompiler, Arena::Tag::tag_comp),
 938       _barrier_set_state(BarrierSet::barrier_set()->barrier_set_c2()->create_barrier_state(comp_arena())),
 939       _env(ci_env),
 940       _directive(directive),
 941       _log(ci_env->log()),
 942       _first_failure_details(nullptr),
 943       _reachability_fences(comp_arena(), 8, 0, nullptr),
 944       _for_post_loop_igvn(comp_arena(), 8, 0, nullptr),
 945       _for_merge_stores_igvn(comp_arena(), 8, 0, nullptr),
 946       _congraph(nullptr),
 947       NOT_PRODUCT(_igv_printer(nullptr) COMMA)
 948       _unique(0),
 949       _dead_node_count(0),
 950       _dead_node_list(comp_arena()),
 951       _node_arena_one(mtCompiler, Arena::Tag::tag_node),
 952       _node_arena_two(mtCompiler, Arena::Tag::tag_node),
 953       _node_arena(&_node_arena_one),
 954       _mach_constant_base_node(nullptr),
 955       _Compile_types(mtCompiler, Arena::Tag::tag_type),
 956       _initial_gvn(nullptr),
 957       _igvn_worklist(nullptr),
 958       _types(nullptr),
 959       _node_hash(nullptr),
 960       _has_mh_late_inlines(false),
 961       _oom(false),
 962       _replay_inline_data(nullptr),
 963       _inline_printer(this),
 964       _java_calls(0),
 965       _inner_loops(0),
 966       _FIRST_STACK_mask(comp_arena()),
 967       _interpreter_frame_size(0),
 968       _regmask_arena(mtCompiler, Arena::Tag::tag_regmask),
 969       _output(nullptr),
 970 #ifndef PRODUCT
 971       _in_dump_cnt(0),
 972 #endif
 973       _allowed_reasons(0) {
 974   C = this;
 975 
 976   // try to reuse an existing stub
 977   {
 978     BlobId blob_id = StubInfo::blob(_stub_id);
 979     CodeBlob* blob = AOTCodeCache::load_code_blob(AOTCodeEntry::C2Blob, blob_id);
 980     if (blob != nullptr) {
 981       RuntimeStub* rs = blob->as_runtime_stub();
 982       _stub_entry_point = rs->entry_point();
 983       return;
 984     }
 985   }
 986 
 987   TraceTime t1(nullptr, &_t_totalCompilation, CITime, false);
 988   TraceTime t2(nullptr, &_t_stubCompilation, CITime, false);
 989 
 990 #ifndef PRODUCT
 991   set_print_assembly(PrintFrameConverterAssembly);
 992   set_parsed_irreducible_loop(false);
 993 #else
 994   set_print_assembly(false); // Must initialize.
 995 #endif
 996   set_has_irreducible_loop(false); // no loops
 997 
 998   CompileWrapper cw(this);
 999   Init(/*do_aliasing=*/ false);
1000   init_tf((*generator)());
1001 
1002   _igvn_worklist = new (comp_arena()) Unique_Node_List(comp_arena());
1003   _types = new (comp_arena()) Type_Array(comp_arena());
1004   _node_hash = new (comp_arena()) NodeHash(comp_arena(), 255);
1005 
1006   if (StressLCM || StressGCM || StressBailout) {
1007     initialize_stress_seed(directive);
1008   }
1009 
1010   {
1011     PhaseGVN gvn;
1012     set_initial_gvn(&gvn);    // not significant, but GraphKit guys use it pervasively
1013     gvn.transform(top());
1014 
1015     GraphKit kit;
1016     kit.gen_stub(stub_function, stub_name, is_fancy_jump, pass_tls, return_pc);
1017   }
1018 
1019   NOT_PRODUCT( verify_graph_edges(); )
1020 
1021   Code_Gen();
1022 }
1023 
1024 Compile::~Compile() {
1025   delete _first_failure_details;
1026 };
1027 
1028 //------------------------------Init-------------------------------------------
1029 // Prepare for a single compilation
1030 void Compile::Init(bool aliasing) {
1031   _do_aliasing = aliasing;
1032   _unique  = 0;
1033   _regalloc = nullptr;
1034 
1035   _tf      = nullptr;  // filled in later
1036   _top     = nullptr;  // cached later
1037   _matcher = nullptr;  // filled in later
1038   _cfg     = nullptr;  // filled in later
1039 
1040   _node_note_array = nullptr;
1041   _default_node_notes = nullptr;
1042   DEBUG_ONLY( _modified_nodes = nullptr; ) // Used in Optimize()
1043 
1044   _immutable_memory = nullptr; // filled in at first inquiry
1045 
1046 #ifdef ASSERT
1047   _phase_optimize_finished = false;
1048   _phase_verify_ideal_loop = false;
1049   _exception_backedge = false;
1050   _type_verify = nullptr;
1051 #endif
1052 
1053   // Globally visible Nodes
1054   // First set TOP to null to give safe behavior during creation of RootNode
1055   set_cached_top_node(nullptr);
1056   set_root(new RootNode());
1057   // Now that you have a Root to point to, create the real TOP
1058   set_cached_top_node( new ConNode(Type::TOP) );
1059   set_recent_alloc(nullptr, nullptr);
1060 
1061   // Create Debug Information Recorder to record scopes, oopmaps, etc.
1062   env()->set_oop_recorder(new OopRecorder(env()->arena()));
1063   env()->set_debug_info(new DebugInformationRecorder(env()->oop_recorder()));
1064   env()->set_dependencies(new Dependencies(env()));
1065 
1066   _fixed_slots = 0;
1067   set_has_split_ifs(false);
1068   set_has_loops(false); // first approximation
1069   set_has_stringbuilder(false);
1070   set_has_boxed_value(false);
1071   _trap_can_recompile = false;  // no traps emitted yet
1072   _major_progress = true; // start out assuming good things will happen
1073   set_has_unsafe_access(false);
1074   set_max_vector_size(0);
1075   set_clear_upper_avx(false);  //false as default for clear upper bits of ymm registers
1076   Copy::zero_to_bytes(_trap_hist, sizeof(_trap_hist));
1077   set_decompile_count(0);
1078 
1079 #ifndef PRODUCT
1080   _phase_counter = 0;
1081   Copy::zero_to_bytes(_igv_phase_iter, sizeof(_igv_phase_iter));
1082 #endif
1083 
1084   set_do_freq_based_layout(_directive->BlockLayoutByFrequencyOption);
1085   _loop_opts_cnt = LoopOptsCount;
1086   set_do_inlining(Inline);
1087   set_max_inline_size(MaxInlineSize);
1088   set_freq_inline_size(FreqInlineSize);
1089   set_do_scheduling(OptoScheduling);
1090 
1091   set_do_vector_loop(false);
1092   set_has_monitors(false);
1093   set_has_scoped_access(false);
1094 
1095   if (AllowVectorizeOnDemand) {
1096     if (has_method() && _directive->VectorizeOption) {
1097       set_do_vector_loop(true);
1098       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());})
1099     } else if (has_method() && method()->name() != nullptr &&
1100                method()->intrinsic_id() == vmIntrinsics::_forEachRemaining) {
1101       set_do_vector_loop(true);
1102     }
1103   }
1104   set_use_cmove(UseCMoveUnconditionally /* || do_vector_loop()*/); //TODO: consider do_vector_loop() mandate use_cmove unconditionally
1105   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());})
1106 
1107   _max_node_limit = _directive->MaxNodeLimitOption;
1108 
1109   if (VM_Version::supports_fast_class_init_checks() && has_method() && !is_osr_compilation() && method()->needs_clinit_barrier()) {
1110     set_clinit_barrier_on_entry(true);
1111   }
1112   if (debug_info()->recording_non_safepoints()) {
1113     set_node_note_array(new(comp_arena()) GrowableArray<Node_Notes*>
1114                         (comp_arena(), 8, 0, nullptr));
1115     set_default_node_notes(Node_Notes::make(this));
1116   }
1117 
1118   const int grow_ats = 16;
1119   _max_alias_types = grow_ats;
1120   _alias_types   = NEW_ARENA_ARRAY(comp_arena(), AliasType*, grow_ats);
1121   AliasType* ats = NEW_ARENA_ARRAY(comp_arena(), AliasType,  grow_ats);
1122   Copy::zero_to_bytes(ats, sizeof(AliasType)*grow_ats);
1123   {
1124     for (int i = 0; i < grow_ats; i++)  _alias_types[i] = &ats[i];
1125   }
1126   // Initialize the first few types.
1127   _alias_types[AliasIdxTop]->Init(AliasIdxTop, nullptr);
1128   _alias_types[AliasIdxBot]->Init(AliasIdxBot, TypePtr::BOTTOM);
1129   _alias_types[AliasIdxRaw]->Init(AliasIdxRaw, TypeRawPtr::BOTTOM);
1130   _num_alias_types = AliasIdxRaw+1;
1131   // Zero out the alias type cache.
1132   Copy::zero_to_bytes(_alias_cache, sizeof(_alias_cache));
1133   // A null adr_type hits in the cache right away.  Preload the right answer.
1134   probe_alias_cache(nullptr)->_index = AliasIdxTop;
1135 }
1136 
1137 #ifdef ASSERT
1138 // Verify that the current StartNode is valid.
1139 void Compile::verify_start(StartNode* s) const {
1140   assert(failing_internal() || s == start(), "should be StartNode");
1141 }
1142 #endif
1143 
1144 /**
1145  * Return the 'StartNode'. We must not have a pending failure, since the ideal graph
1146  * can be in an inconsistent state, i.e., we can get segmentation faults when traversing
1147  * the ideal graph.
1148  */
1149 StartNode* Compile::start() const {
1150   assert (!failing_internal() || C->failure_is_artificial(), "Must not have pending failure. Reason is: %s", failure_reason());
1151   for (DUIterator_Fast imax, i = root()->fast_outs(imax); i < imax; i++) {
1152     Node* start = root()->fast_out(i);
1153     if (start->is_Start()) {
1154       return start->as_Start();
1155     }
1156   }
1157   fatal("Did not find Start node!");
1158   return nullptr;
1159 }
1160 
1161 //-------------------------------immutable_memory-------------------------------------
1162 // Access immutable memory
1163 Node* Compile::immutable_memory() {
1164   if (_immutable_memory != nullptr) {
1165     return _immutable_memory;
1166   }
1167   StartNode* s = start();
1168   for (DUIterator_Fast imax, i = s->fast_outs(imax); true; i++) {
1169     Node *p = s->fast_out(i);
1170     if (p != s && p->as_Proj()->_con == TypeFunc::Memory) {
1171       _immutable_memory = p;
1172       return _immutable_memory;
1173     }
1174   }
1175   ShouldNotReachHere();
1176   return nullptr;
1177 }
1178 
1179 //----------------------set_cached_top_node------------------------------------
1180 // Install the cached top node, and make sure Node::is_top works correctly.
1181 void Compile::set_cached_top_node(Node* tn) {
1182   if (tn != nullptr)  verify_top(tn);
1183   Node* old_top = _top;
1184   _top = tn;
1185   // Calling Node::setup_is_top allows the nodes the chance to adjust
1186   // their _out arrays.
1187   if (_top != nullptr)     _top->setup_is_top();
1188   if (old_top != nullptr)  old_top->setup_is_top();
1189   assert(_top == nullptr || top()->is_top(), "");
1190 }
1191 
1192 #ifdef ASSERT
1193 uint Compile::count_live_nodes_by_graph_walk() {
1194   Unique_Node_List useful(comp_arena());
1195   // Get useful node list by walking the graph.
1196   identify_useful_nodes(useful);
1197   return useful.size();
1198 }
1199 
1200 void Compile::print_missing_nodes() {
1201 
1202   // Return if CompileLog is null and PrintIdealNodeCount is false.
1203   if ((_log == nullptr) && (! PrintIdealNodeCount)) {
1204     return;
1205   }
1206 
1207   // This is an expensive function. It is executed only when the user
1208   // specifies VerifyIdealNodeCount option or otherwise knows the
1209   // additional work that needs to be done to identify reachable nodes
1210   // by walking the flow graph and find the missing ones using
1211   // _dead_node_list.
1212 
1213   Unique_Node_List useful(comp_arena());
1214   // Get useful node list by walking the graph.
1215   identify_useful_nodes(useful);
1216 
1217   uint l_nodes = C->live_nodes();
1218   uint l_nodes_by_walk = useful.size();
1219 
1220   if (l_nodes != l_nodes_by_walk) {
1221     if (_log != nullptr) {
1222       _log->begin_head("mismatched_nodes count='%d'", abs((int) (l_nodes - l_nodes_by_walk)));
1223       _log->stamp();
1224       _log->end_head();
1225     }
1226     VectorSet& useful_member_set = useful.member_set();
1227     int last_idx = l_nodes_by_walk;
1228     for (int i = 0; i < last_idx; i++) {
1229       if (useful_member_set.test(i)) {
1230         if (_dead_node_list.test(i)) {
1231           if (_log != nullptr) {
1232             _log->elem("mismatched_node_info node_idx='%d' type='both live and dead'", i);
1233           }
1234           if (PrintIdealNodeCount) {
1235             // Print the log message to tty
1236               tty->print_cr("mismatched_node idx='%d' both live and dead'", i);
1237               useful.at(i)->dump();
1238           }
1239         }
1240       }
1241       else if (! _dead_node_list.test(i)) {
1242         if (_log != nullptr) {
1243           _log->elem("mismatched_node_info node_idx='%d' type='neither live nor dead'", i);
1244         }
1245         if (PrintIdealNodeCount) {
1246           // Print the log message to tty
1247           tty->print_cr("mismatched_node idx='%d' type='neither live nor dead'", i);
1248         }
1249       }
1250     }
1251     if (_log != nullptr) {
1252       _log->tail("mismatched_nodes");
1253     }
1254   }
1255 }
1256 void Compile::record_modified_node(Node* n) {
1257   if (_modified_nodes != nullptr && !_inlining_incrementally && !n->is_Con()) {
1258     _modified_nodes->push(n);
1259   }
1260 }
1261 
1262 void Compile::remove_modified_node(Node* n) {
1263   if (_modified_nodes != nullptr) {
1264     _modified_nodes->remove(n);
1265   }
1266 }
1267 #endif
1268 
1269 #ifndef PRODUCT
1270 void Compile::verify_top(Node* tn) const {
1271   if (tn != nullptr) {
1272     assert(tn->is_Con(), "top node must be a constant");
1273     assert(((ConNode*)tn)->type() == Type::TOP, "top node must have correct type");
1274     assert(tn->in(0) != nullptr, "must have live top node");
1275   }
1276 }
1277 #endif
1278 
1279 
1280 ///-------------------Managing Per-Node Debug & Profile Info-------------------
1281 
1282 void Compile::grow_node_notes(GrowableArray<Node_Notes*>* arr, int grow_by) {
1283   guarantee(arr != nullptr, "");
1284   int num_blocks = arr->length();
1285   if (grow_by < num_blocks)  grow_by = num_blocks;
1286   int num_notes = grow_by * _node_notes_block_size;
1287   Node_Notes* notes = NEW_ARENA_ARRAY(node_arena(), Node_Notes, num_notes);
1288   Copy::zero_to_bytes(notes, num_notes * sizeof(Node_Notes));
1289   while (num_notes > 0) {
1290     arr->append(notes);
1291     notes     += _node_notes_block_size;
1292     num_notes -= _node_notes_block_size;
1293   }
1294   assert(num_notes == 0, "exact multiple, please");
1295 }
1296 
1297 bool Compile::copy_node_notes_to(Node* dest, Node* source) {
1298   if (source == nullptr || dest == nullptr)  return false;
1299 
1300   if (dest->is_Con())
1301     return false;               // Do not push debug info onto constants.
1302 
1303 #ifdef ASSERT
1304   // Leave a bread crumb trail pointing to the original node:
1305   if (dest != nullptr && dest != source && dest->debug_orig() == nullptr) {
1306     dest->set_debug_orig(source);
1307   }
1308 #endif
1309 
1310   if (node_note_array() == nullptr)
1311     return false;               // Not collecting any notes now.
1312 
1313   // This is a copy onto a pre-existing node, which may already have notes.
1314   // If both nodes have notes, do not overwrite any pre-existing notes.
1315   Node_Notes* source_notes = node_notes_at(source->_idx);
1316   if (source_notes == nullptr || source_notes->is_clear())  return false;
1317   Node_Notes* dest_notes   = node_notes_at(dest->_idx);
1318   if (dest_notes == nullptr || dest_notes->is_clear()) {
1319     return set_node_notes_at(dest->_idx, source_notes);
1320   }
1321 
1322   Node_Notes merged_notes = (*source_notes);
1323   // The order of operations here ensures that dest notes will win...
1324   merged_notes.update_from(dest_notes);
1325   return set_node_notes_at(dest->_idx, &merged_notes);
1326 }
1327 
1328 
1329 //--------------------------allow_range_check_smearing-------------------------
1330 // Gating condition for coalescing similar range checks.
1331 // Sometimes we try 'speculatively' replacing a series of a range checks by a
1332 // single covering check that is at least as strong as any of them.
1333 // If the optimization succeeds, the simplified (strengthened) range check
1334 // will always succeed.  If it fails, we will deopt, and then give up
1335 // on the optimization.
1336 bool Compile::allow_range_check_smearing() const {
1337   // If this method has already thrown a range-check,
1338   // assume it was because we already tried range smearing
1339   // and it failed.
1340   uint already_trapped = trap_count(Deoptimization::Reason_range_check);
1341   return !already_trapped;
1342 }
1343 
1344 
1345 //------------------------------flatten_alias_type-----------------------------
1346 const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
1347   assert(do_aliasing(), "Aliasing should be enabled");
1348   int offset = tj->offset();
1349   TypePtr::PTR ptr = tj->ptr();
1350 
1351   // Known instance (scalarizable allocation) alias only with itself.
1352   bool is_known_inst = tj->isa_oopptr() != nullptr &&
1353                        tj->is_oopptr()->is_known_instance();
1354 
1355   // Process weird unsafe references.
1356   if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
1357     assert(InlineUnsafeOps || StressReflectiveCode, "indeterminate pointers come only from unsafe ops");
1358     assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
1359     tj = TypeOopPtr::BOTTOM;
1360     ptr = tj->ptr();
1361     offset = tj->offset();
1362   }
1363 
1364   // Array pointers need some flattening
1365   const TypeAryPtr* ta = tj->isa_aryptr();
1366   if (ta && ta->is_stable()) {
1367     // Erase stability property for alias analysis.
1368     tj = ta = ta->cast_to_stable(false);
1369   }
1370   if( ta && is_known_inst ) {
1371     if ( offset != Type::OffsetBot &&
1372          offset > arrayOopDesc::length_offset_in_bytes() ) {
1373       offset = Type::OffsetBot; // Flatten constant access into array body only
1374       tj = ta = ta->
1375               remove_speculative()->
1376               cast_to_ptr_type(ptr)->
1377               with_offset(offset);
1378     }
1379   } else if (ta != nullptr) {
1380     // Common slices
1381     if (offset == arrayOopDesc::length_offset_in_bytes()) {
1382       return TypeAryPtr::RANGE;
1383     } else if (offset == oopDesc::klass_offset_in_bytes()) {
1384       return TypeInstPtr::KLASS;
1385     } else if (offset == oopDesc::mark_offset_in_bytes()) {
1386       return TypeInstPtr::MARK;
1387     }
1388 
1389     // Remove size and stability
1390     const TypeAry* normalized_ary = TypeAry::make(ta->elem(), TypeInt::POS, false);
1391     // Remove ptr, const_oop, and offset
1392     if (ta->elem() == Type::BOTTOM) {
1393       // Bottom array (meet of int[] and byte[] for example), accesses to it will be done with
1394       // Unsafe. This should alias with all arrays. For now just leave it as it is (this is
1395       // incorrect, see JDK-8331133).
1396       tj = ta = TypeAryPtr::make(TypePtr::BotPTR, nullptr, normalized_ary, nullptr, false, Type::OffsetBot);
1397     } else if (ta->elem()->make_oopptr() != nullptr) {
1398       // Object arrays, all of them share the same slice
1399       const TypeAry* tary = TypeAry::make(TypeInstPtr::BOTTOM, TypeInt::POS, false);
1400       tj = ta = TypeAryPtr::make(TypePtr::BotPTR, nullptr, tary, nullptr, false, Type::OffsetBot);
1401     } else {
1402       // Primitive arrays
1403       tj = ta = TypeAryPtr::make(TypePtr::BotPTR, nullptr, normalized_ary, ta->exact_klass(), true, Type::OffsetBot);
1404     }
1405 
1406     // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
1407     // cannot be distinguished by bytecode alone.
1408     if (ta->elem() == TypeInt::BOOL) {
1409       tj = ta = TypeAryPtr::BYTES;
1410     }
1411   }
1412 
1413   // Oop pointers need some flattening
1414   const TypeInstPtr *to = tj->isa_instptr();
1415   if (to && to != TypeOopPtr::BOTTOM) {
1416     ciInstanceKlass* ik = to->instance_klass();
1417     if( ptr == TypePtr::Constant ) {
1418       if (ik != ciEnv::current()->Class_klass() ||
1419           offset < ik->layout_helper_size_in_bytes()) {
1420         // No constant oop pointers (such as Strings); they alias with
1421         // unknown strings.
1422         assert(!is_known_inst, "not scalarizable allocation");
1423         tj = to = to->
1424                 cast_to_instance_id(TypeOopPtr::InstanceBot)->
1425                 remove_speculative()->
1426                 cast_to_ptr_type(TypePtr::BotPTR)->
1427                 cast_to_exactness(false);
1428       }
1429     } else if( is_known_inst ) {
1430       tj = to; // Keep NotNull and klass_is_exact for instance type
1431     } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
1432       // During the 2nd round of IterGVN, NotNull castings are removed.
1433       // Make sure the Bottom and NotNull variants alias the same.
1434       // Also, make sure exact and non-exact variants alias the same.
1435       tj = to = to->
1436               remove_speculative()->
1437               cast_to_instance_id(TypeOopPtr::InstanceBot)->
1438               cast_to_ptr_type(TypePtr::BotPTR)->
1439               cast_to_exactness(false);
1440     }
1441     if (to->speculative() != nullptr) {
1442       tj = to = to->remove_speculative();
1443     }
1444     // Canonicalize the holder of this field
1445     if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
1446       // First handle header references such as a LoadKlassNode, even if the
1447       // object's klass is unloaded at compile time (4965979).
1448       if (!is_known_inst) { // Do it only for non-instance types
1449         tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, nullptr, offset);
1450       }
1451     } else if (offset < 0 || offset >= ik->layout_helper_size_in_bytes()) {
1452       // Static fields are in the space above the normal instance
1453       // fields in the java.lang.Class instance.
1454       if (ik != ciEnv::current()->Class_klass()) {
1455         to = nullptr;
1456         tj = TypeOopPtr::BOTTOM;
1457         offset = tj->offset();
1458       }
1459     } else {
1460       ciInstanceKlass *canonical_holder = ik->get_canonical_holder(offset);
1461       assert(offset < canonical_holder->layout_helper_size_in_bytes(), "");
1462       assert(tj->offset() == offset, "no change to offset expected");
1463       bool xk = to->klass_is_exact();
1464       int instance_id = to->instance_id();
1465 
1466       // If the input type's class is the holder: if exact, the type only includes interfaces implemented by the holder
1467       // but if not exact, it may include extra interfaces: build new type from the holder class to make sure only
1468       // its interfaces are included.
1469       if (xk && ik->equals(canonical_holder)) {
1470         assert(tj == TypeInstPtr::make(to->ptr(), canonical_holder, is_known_inst, nullptr, offset, instance_id), "exact type should be canonical type");
1471       } else {
1472         assert(xk || !is_known_inst, "Known instance should be exact type");
1473         tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, is_known_inst, nullptr, offset, instance_id);
1474       }
1475     }
1476   }
1477 
1478   // Klass pointers to object array klasses need some flattening
1479   const TypeKlassPtr *tk = tj->isa_klassptr();
1480   if( tk ) {
1481     // If we are referencing a field within a Klass, we need
1482     // to assume the worst case of an Object.  Both exact and
1483     // inexact types must flatten to the same alias class so
1484     // use NotNull as the PTR.
1485     if ( offset == Type::OffsetBot || (offset >= 0 && (size_t)offset < sizeof(Klass)) ) {
1486       tj = tk = TypeInstKlassPtr::make(TypePtr::NotNull,
1487                                        env()->Object_klass(),
1488                                        offset);
1489     }
1490 
1491     if (tk->isa_aryklassptr() && tk->is_aryklassptr()->elem()->isa_klassptr()) {
1492       ciKlass* k = ciObjArrayKlass::make(env()->Object_klass());
1493       if (!k || !k->is_loaded()) {                  // Only fails for some -Xcomp runs
1494         tj = tk = TypeInstKlassPtr::make(TypePtr::NotNull, env()->Object_klass(), offset);
1495       } else {
1496         tj = tk = TypeAryKlassPtr::make(TypePtr::NotNull, tk->is_aryklassptr()->elem(), k, offset);
1497       }
1498     }
1499 
1500     // Check for precise loads from the primary supertype array and force them
1501     // to the supertype cache alias index.  Check for generic array loads from
1502     // the primary supertype array and also force them to the supertype cache
1503     // alias index.  Since the same load can reach both, we need to merge
1504     // these 2 disparate memories into the same alias class.  Since the
1505     // primary supertype array is read-only, there's no chance of confusion
1506     // where we bypass an array load and an array store.
1507     int primary_supers_offset = in_bytes(Klass::primary_supers_offset());
1508     if (offset == Type::OffsetBot ||
1509         (offset >= primary_supers_offset &&
1510          offset < (int)(primary_supers_offset + Klass::primary_super_limit() * wordSize)) ||
1511         offset == (int)in_bytes(Klass::secondary_super_cache_offset())) {
1512       offset = in_bytes(Klass::secondary_super_cache_offset());
1513       tj = tk = tk->with_offset(offset);
1514     }
1515   }
1516 
1517   // Flatten all Raw pointers together.
1518   if (tj->base() == Type::RawPtr)
1519     tj = TypeRawPtr::BOTTOM;
1520 
1521   if (tj->base() == Type::AnyPtr)
1522     tj = TypePtr::BOTTOM;      // An error, which the caller must check for.
1523 
1524   offset = tj->offset();
1525   assert( offset != Type::OffsetTop, "Offset has fallen from constant" );
1526 
1527   assert( (offset != Type::OffsetBot && tj->base() != Type::AryPtr) ||
1528           (offset == Type::OffsetBot && tj->base() == Type::AryPtr) ||
1529           (offset == Type::OffsetBot && tj == TypeOopPtr::BOTTOM) ||
1530           (offset == Type::OffsetBot && tj == TypePtr::BOTTOM) ||
1531           (offset == oopDesc::mark_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1532           (offset == oopDesc::klass_offset_in_bytes() && tj->base() == Type::AryPtr) ||
1533           (offset == arrayOopDesc::length_offset_in_bytes() && tj->base() == Type::AryPtr),
1534           "For oops, klasses, raw offset must be constant; for arrays the offset is never known" );
1535   assert( tj->ptr() != TypePtr::TopPTR &&
1536           tj->ptr() != TypePtr::AnyNull &&
1537           tj->ptr() != TypePtr::Null, "No imprecise addresses" );
1538 //    assert( tj->ptr() != TypePtr::Constant ||
1539 //            tj->base() == Type::RawPtr ||
1540 //            tj->base() == Type::KlassPtr, "No constant oop addresses" );
1541 
1542   return tj;
1543 }
1544 
1545 void Compile::AliasType::Init(int i, const TypePtr* at) {
1546   assert(AliasIdxTop <= i && i < Compile::current()->_max_alias_types, "Invalid alias index");
1547   _index = i;
1548   _adr_type = at;
1549   _field = nullptr;
1550   _element = nullptr;
1551   _is_rewritable = true; // default
1552   const TypeOopPtr *atoop = (at != nullptr) ? at->isa_oopptr() : nullptr;
1553   if (atoop != nullptr && atoop->is_known_instance()) {
1554     const TypeOopPtr *gt = atoop->cast_to_instance_id(TypeOopPtr::InstanceBot);
1555     _general_index = Compile::current()->get_alias_index(gt);
1556   } else {
1557     _general_index = 0;
1558   }
1559 }
1560 
1561 BasicType Compile::AliasType::basic_type() const {
1562   if (element() != nullptr) {
1563     const Type* element = adr_type()->is_aryptr()->elem();
1564     return element->isa_narrowoop() ? T_OBJECT : element->array_element_basic_type();
1565   } if (field() != nullptr) {
1566     return field()->layout_type();
1567   } else {
1568     return T_ILLEGAL; // unknown
1569   }
1570 }
1571 
1572 //---------------------------------print_on------------------------------------
1573 #ifndef PRODUCT
1574 void Compile::AliasType::print_on(outputStream* st) {
1575   if (index() < 10)
1576         st->print("@ <%d> ", index());
1577   else  st->print("@ <%d>",  index());
1578   st->print(is_rewritable() ? "   " : " RO");
1579   int offset = adr_type()->offset();
1580   if (offset == Type::OffsetBot)
1581         st->print(" +any");
1582   else  st->print(" +%-3d", offset);
1583   st->print(" in ");
1584   adr_type()->dump_on(st);
1585   const TypeOopPtr* tjp = adr_type()->isa_oopptr();
1586   if (field() != nullptr && tjp) {
1587     if (tjp->is_instptr()->instance_klass()  != field()->holder() ||
1588         tjp->offset() != field()->offset_in_bytes()) {
1589       st->print(" != ");
1590       field()->print();
1591       st->print(" ***");
1592     }
1593   }
1594 }
1595 
1596 void print_alias_types() {
1597   Compile* C = Compile::current();
1598   tty->print_cr("--- Alias types, AliasIdxBot .. %d", C->num_alias_types()-1);
1599   for (int idx = Compile::AliasIdxBot; idx < C->num_alias_types(); idx++) {
1600     C->alias_type(idx)->print_on(tty);
1601     tty->cr();
1602   }
1603 }
1604 #endif
1605 
1606 
1607 //----------------------------probe_alias_cache--------------------------------
1608 Compile::AliasCacheEntry* Compile::probe_alias_cache(const TypePtr* adr_type) {
1609   intptr_t key = (intptr_t) adr_type;
1610   key ^= key >> logAliasCacheSize;
1611   return &_alias_cache[key & right_n_bits(logAliasCacheSize)];
1612 }
1613 
1614 
1615 //-----------------------------grow_alias_types--------------------------------
1616 void Compile::grow_alias_types() {
1617   const int old_ats  = _max_alias_types; // how many before?
1618   const int new_ats  = old_ats;          // how many more?
1619   const int grow_ats = old_ats+new_ats;  // how many now?
1620   _max_alias_types = grow_ats;
1621   _alias_types =  REALLOC_ARENA_ARRAY(comp_arena(), _alias_types, old_ats, grow_ats);
1622   AliasType* ats =    NEW_ARENA_ARRAY(comp_arena(), AliasType, new_ats);
1623   Copy::zero_to_bytes(ats, sizeof(AliasType)*new_ats);
1624   for (int i = 0; i < new_ats; i++)  _alias_types[old_ats+i] = &ats[i];
1625 }
1626 
1627 
1628 //--------------------------------find_alias_type------------------------------
1629 Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_create, ciField* original_field) {
1630   if (!do_aliasing()) {
1631     return alias_type(AliasIdxBot);
1632   }
1633 
1634   AliasCacheEntry* ace = probe_alias_cache(adr_type);
1635   if (ace->_adr_type == adr_type) {
1636     return alias_type(ace->_index);
1637   }
1638 
1639   // Handle special cases.
1640   if (adr_type == nullptr)          return alias_type(AliasIdxTop);
1641   if (adr_type == TypePtr::BOTTOM)  return alias_type(AliasIdxBot);
1642 
1643   // Do it the slow way.
1644   const TypePtr* flat = flatten_alias_type(adr_type);
1645 
1646 #ifdef ASSERT
1647   {
1648     ResourceMark rm;
1649     assert(flat == flatten_alias_type(flat), "not idempotent: adr_type = %s; flat = %s => %s",
1650            Type::str(adr_type), Type::str(flat), Type::str(flatten_alias_type(flat)));
1651     assert(flat != TypePtr::BOTTOM, "cannot alias-analyze an untyped ptr: adr_type = %s",
1652            Type::str(adr_type));
1653     if (flat->isa_oopptr() && !flat->isa_klassptr()) {
1654       const TypeOopPtr* foop = flat->is_oopptr();
1655       // Scalarizable allocations have exact klass always.
1656       bool exact = !foop->klass_is_exact() || foop->is_known_instance();
1657       const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
1658       assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type: foop = %s; xoop = %s",
1659              Type::str(foop), Type::str(xoop));
1660     }
1661   }
1662 #endif
1663 
1664   int idx = AliasIdxTop;
1665   for (int i = 0; i < num_alias_types(); i++) {
1666     if (alias_type(i)->adr_type() == flat) {
1667       idx = i;
1668       break;
1669     }
1670   }
1671 
1672   if (idx == AliasIdxTop) {
1673     if (no_create)  return nullptr;
1674     // Grow the array if necessary.
1675     if (_num_alias_types == _max_alias_types)  grow_alias_types();
1676     // Add a new alias type.
1677     idx = _num_alias_types++;
1678     _alias_types[idx]->Init(idx, flat);
1679     if (flat == TypeInstPtr::KLASS)  alias_type(idx)->set_rewritable(false);
1680     if (flat == TypeAryPtr::RANGE)   alias_type(idx)->set_rewritable(false);
1681     if (flat->isa_instptr()) {
1682       if (flat->offset() == java_lang_Class::klass_offset()
1683           && flat->is_instptr()->instance_klass() == env()->Class_klass())
1684         alias_type(idx)->set_rewritable(false);
1685     }
1686     if (flat->isa_aryptr()) {
1687 #ifdef ASSERT
1688       const int header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
1689       // (T_BYTE has the weakest alignment and size restrictions...)
1690       assert(flat->offset() < header_size_min, "array body reference must be OffsetBot");
1691 #endif
1692       if (flat->offset() == TypePtr::OffsetBot) {
1693         alias_type(idx)->set_element(flat->is_aryptr()->elem());
1694       }
1695     }
1696     if (flat->isa_klassptr()) {
1697       if (UseCompactObjectHeaders) {
1698         if (flat->offset() == in_bytes(Klass::prototype_header_offset()))
1699           alias_type(idx)->set_rewritable(false);
1700       }
1701       if (flat->offset() == in_bytes(Klass::super_check_offset_offset()))
1702         alias_type(idx)->set_rewritable(false);
1703       if (flat->offset() == in_bytes(Klass::misc_flags_offset()))
1704         alias_type(idx)->set_rewritable(false);
1705       if (flat->offset() == in_bytes(Klass::java_mirror_offset()))
1706         alias_type(idx)->set_rewritable(false);
1707       if (flat->offset() == in_bytes(Klass::secondary_super_cache_offset()))
1708         alias_type(idx)->set_rewritable(false);
1709     }
1710 
1711     if (flat->isa_instklassptr()) {
1712       if (flat->offset() == in_bytes(InstanceKlass::access_flags_offset())) {
1713         alias_type(idx)->set_rewritable(false);
1714       }
1715     }
1716     // %%% (We would like to finalize JavaThread::threadObj_offset(),
1717     // but the base pointer type is not distinctive enough to identify
1718     // references into JavaThread.)
1719 
1720     // Check for final fields.
1721     const TypeInstPtr* tinst = flat->isa_instptr();
1722     if (tinst && tinst->offset() >= instanceOopDesc::base_offset_in_bytes()) {
1723       ciField* field;
1724       if (tinst->const_oop() != nullptr &&
1725           tinst->instance_klass() == ciEnv::current()->Class_klass() &&
1726           tinst->offset() >= (tinst->instance_klass()->layout_helper_size_in_bytes())) {
1727         // static field
1728         ciInstanceKlass* k = tinst->const_oop()->as_instance()->java_lang_Class_klass()->as_instance_klass();
1729         field = k->get_field_by_offset(tinst->offset(), true);
1730       } else {
1731         ciInstanceKlass *k = tinst->instance_klass();
1732         field = k->get_field_by_offset(tinst->offset(), false);
1733       }
1734       assert(field == nullptr ||
1735              original_field == nullptr ||
1736              (field->holder() == original_field->holder() &&
1737               field->offset_in_bytes() == original_field->offset_in_bytes() &&
1738               field->is_static() == original_field->is_static()), "wrong field?");
1739       // Set field() and is_rewritable() attributes.
1740       if (field != nullptr)  alias_type(idx)->set_field(field);
1741     }
1742   }
1743 
1744   // Fill the cache for next time.
1745   ace->_adr_type = adr_type;
1746   ace->_index    = idx;
1747   assert(alias_type(adr_type) == alias_type(idx),  "type must be installed");
1748 
1749   // Might as well try to fill the cache for the flattened version, too.
1750   AliasCacheEntry* face = probe_alias_cache(flat);
1751   if (face->_adr_type == nullptr) {
1752     face->_adr_type = flat;
1753     face->_index    = idx;
1754     assert(alias_type(flat) == alias_type(idx), "flat type must work too");
1755   }
1756 
1757   return alias_type(idx);
1758 }
1759 
1760 
1761 Compile::AliasType* Compile::alias_type(ciField* field) {
1762   const TypeOopPtr* t;
1763   if (field->is_static())
1764     t = TypeInstPtr::make(field->holder()->java_mirror());
1765   else
1766     t = TypeOopPtr::make_from_klass_raw(field->holder());
1767   AliasType* atp = alias_type(t->add_offset(field->offset_in_bytes()), field);
1768   assert((field->is_final() || field->is_stable()) == !atp->is_rewritable(), "must get the rewritable bits correct");
1769   return atp;
1770 }
1771 
1772 
1773 //------------------------------have_alias_type--------------------------------
1774 bool Compile::have_alias_type(const TypePtr* adr_type) {
1775   AliasCacheEntry* ace = probe_alias_cache(adr_type);
1776   if (ace->_adr_type == adr_type) {
1777     return true;
1778   }
1779 
1780   // Handle special cases.
1781   if (adr_type == nullptr)             return true;
1782   if (adr_type == TypePtr::BOTTOM)  return true;
1783 
1784   return find_alias_type(adr_type, true, nullptr) != nullptr;
1785 }
1786 
1787 //-----------------------------must_alias--------------------------------------
1788 // True if all values of the given address type are in the given alias category.
1789 bool Compile::must_alias(const TypePtr* adr_type, int alias_idx) {
1790   if (alias_idx == AliasIdxBot)         return true;  // the universal category
1791   if (adr_type == nullptr)              return true;  // null serves as TypePtr::TOP
1792   if (alias_idx == AliasIdxTop)         return false; // the empty category
1793   if (adr_type->base() == Type::AnyPtr) return false; // TypePtr::BOTTOM or its twins
1794 
1795   // the only remaining possible overlap is identity
1796   int adr_idx = get_alias_index(adr_type);
1797   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1798   assert(adr_idx == alias_idx ||
1799          (alias_type(alias_idx)->adr_type() != TypeOopPtr::BOTTOM
1800           && adr_type                       != TypeOopPtr::BOTTOM),
1801          "should not be testing for overlap with an unsafe pointer");
1802   return adr_idx == alias_idx;
1803 }
1804 
1805 //------------------------------can_alias--------------------------------------
1806 // True if any values of the given address type are in the given alias category.
1807 bool Compile::can_alias(const TypePtr* adr_type, int alias_idx) {
1808   if (alias_idx == AliasIdxTop)         return false; // the empty category
1809   if (adr_type == nullptr)              return false; // null serves as TypePtr::TOP
1810   // Known instance doesn't alias with bottom memory
1811   if (alias_idx == AliasIdxBot)         return !adr_type->is_known_instance();                   // the universal category
1812   if (adr_type->base() == Type::AnyPtr) return !C->get_adr_type(alias_idx)->is_known_instance(); // TypePtr::BOTTOM or its twins
1813 
1814   // the only remaining possible overlap is identity
1815   int adr_idx = get_alias_index(adr_type);
1816   assert(adr_idx != AliasIdxBot && adr_idx != AliasIdxTop, "");
1817   return adr_idx == alias_idx;
1818 }
1819 
1820 // Mark all ParsePredicateNodes as useless. They will later be removed from the graph in IGVN together with their
1821 // uncommon traps if no Runtime Predicates were created from the Parse Predicates.
1822 void Compile::mark_parse_predicate_nodes_useless(PhaseIterGVN& igvn) {
1823   if (parse_predicate_count() == 0) {
1824     return;
1825   }
1826   for (int i = 0; i < parse_predicate_count(); i++) {
1827     ParsePredicateNode* parse_predicate = _parse_predicates.at(i);
1828     parse_predicate->mark_useless(igvn);
1829   }
1830   _parse_predicates.clear();
1831 }
1832 
1833 void Compile::record_for_post_loop_opts_igvn(Node* n) {
1834   if (!n->for_post_loop_opts_igvn()) {
1835     assert(!_for_post_loop_igvn.contains(n), "duplicate");
1836     n->add_flag(Node::NodeFlags::Flag_for_post_loop_opts_igvn);
1837     _for_post_loop_igvn.append(n);
1838   }
1839 }
1840 
1841 void Compile::remove_from_post_loop_opts_igvn(Node* n) {
1842   n->remove_flag(Node::NodeFlags::Flag_for_post_loop_opts_igvn);
1843   _for_post_loop_igvn.remove(n);
1844 }
1845 
1846 void Compile::process_for_post_loop_opts_igvn(PhaseIterGVN& igvn) {
1847   // Verify that all previous optimizations produced a valid graph
1848   // at least to this point, even if no loop optimizations were done.
1849   PhaseIdealLoop::verify(igvn);
1850 
1851   if (_print_phase_loop_opts) {
1852     print_method(PHASE_AFTER_LOOP_OPTS, 2);
1853   }
1854   C->set_post_loop_opts_phase(); // no more loop opts allowed
1855 
1856   assert(!C->major_progress(), "not cleared");
1857 
1858   if (_for_post_loop_igvn.length() > 0) {
1859     while (_for_post_loop_igvn.length() > 0) {
1860       Node* n = _for_post_loop_igvn.pop();
1861       n->remove_flag(Node::NodeFlags::Flag_for_post_loop_opts_igvn);
1862       igvn._worklist.push(n);
1863     }
1864     igvn.optimize();
1865     if (failing()) return;
1866     assert(_for_post_loop_igvn.length() == 0, "no more delayed nodes allowed");
1867     assert(C->parse_predicate_count() == 0, "all parse predicates should have been removed now");
1868 
1869     // Sometimes IGVN sets major progress (e.g., when processing loop nodes).
1870     if (C->major_progress()) {
1871       C->clear_major_progress(); // ensure that major progress is now clear
1872     }
1873   }
1874 }
1875 
1876 void Compile::record_for_merge_stores_igvn(Node* n) {
1877   if (!n->for_merge_stores_igvn()) {
1878     assert(!_for_merge_stores_igvn.contains(n), "duplicate");
1879     n->add_flag(Node::NodeFlags::Flag_for_merge_stores_igvn);
1880     _for_merge_stores_igvn.append(n);
1881   }
1882 }
1883 
1884 void Compile::remove_from_merge_stores_igvn(Node* n) {
1885   n->remove_flag(Node::NodeFlags::Flag_for_merge_stores_igvn);
1886   _for_merge_stores_igvn.remove(n);
1887 }
1888 
1889 // We need to wait with merging stores until RangeCheck smearing has removed the RangeChecks during
1890 // the post loops IGVN phase. If we do it earlier, then there may still be some RangeChecks between
1891 // the stores, and we merge the wrong sequence of stores.
1892 // Example:
1893 //   StoreI RangeCheck StoreI StoreI RangeCheck StoreI
1894 // Apply MergeStores:
1895 //   StoreI RangeCheck [   StoreL  ] RangeCheck StoreI
1896 // Remove more RangeChecks:
1897 //   StoreI            [   StoreL  ]            StoreI
1898 // But now it would have been better to do this instead:
1899 //   [         StoreL       ] [       StoreL         ]
1900 //
1901 // Note: we allow stores to merge in this dedicated IGVN round, and any later IGVN round,
1902 //       since we never unset _merge_stores_phase.
1903 void Compile::process_for_merge_stores_igvn(PhaseIterGVN& igvn) {
1904   C->set_merge_stores_phase();
1905 
1906   if (_for_merge_stores_igvn.length() > 0) {
1907     while (_for_merge_stores_igvn.length() > 0) {
1908       Node* n = _for_merge_stores_igvn.pop();
1909       n->remove_flag(Node::NodeFlags::Flag_for_merge_stores_igvn);
1910       igvn._worklist.push(n);
1911     }
1912     igvn.optimize();
1913     if (failing()) return;
1914     assert(_for_merge_stores_igvn.length() == 0, "no more delayed nodes allowed");
1915     print_method(PHASE_AFTER_MERGE_STORES, 3);
1916   }
1917 }
1918 
1919 void Compile::record_unstable_if_trap(UnstableIfTrap* trap) {
1920   if (OptimizeUnstableIf) {
1921     _unstable_if_traps.append(trap);
1922   }
1923 }
1924 
1925 void Compile::remove_useless_unstable_if_traps(Unique_Node_List& useful) {
1926   for (int i = _unstable_if_traps.length() - 1; i >= 0; i--) {
1927     UnstableIfTrap* trap = _unstable_if_traps.at(i);
1928     Node* n = trap->uncommon_trap();
1929     if (!useful.member(n)) {
1930       _unstable_if_traps.delete_at(i); // replaces i-th with last element which is known to be useful (already processed)
1931     }
1932   }
1933 }
1934 
1935 // Remove the unstable if trap associated with 'unc' from candidates. It is either dead
1936 // or fold-compares case. Return true if succeed or not found.
1937 //
1938 // In rare cases, the found trap has been processed. It is too late to delete it. Return
1939 // false and ask fold-compares to yield.
1940 //
1941 // 'fold-compares' may use the uncommon_trap of the dominating IfNode to cover the fused
1942 // IfNode. This breaks the unstable_if trap invariant: control takes the unstable path
1943 // when deoptimization does happen.
1944 bool Compile::remove_unstable_if_trap(CallStaticJavaNode* unc, bool yield) {
1945   for (int i = 0; i < _unstable_if_traps.length(); ++i) {
1946     UnstableIfTrap* trap = _unstable_if_traps.at(i);
1947     if (trap->uncommon_trap() == unc) {
1948       if (yield && trap->modified()) {
1949         return false;
1950       }
1951       _unstable_if_traps.delete_at(i);
1952       break;
1953     }
1954   }
1955   return true;
1956 }
1957 
1958 // Re-calculate unstable_if traps with the liveness of next_bci, which points to the unlikely path.
1959 // It needs to be done after igvn because fold-compares may fuse uncommon_traps and before renumbering.
1960 void Compile::process_for_unstable_if_traps(PhaseIterGVN& igvn) {
1961   for (int i = _unstable_if_traps.length() - 1; i >= 0; --i) {
1962     UnstableIfTrap* trap = _unstable_if_traps.at(i);
1963     CallStaticJavaNode* unc = trap->uncommon_trap();
1964     int next_bci = trap->next_bci();
1965     bool modified = trap->modified();
1966 
1967     if (next_bci != -1 && !modified) {
1968       assert(!_dead_node_list.test(unc->_idx), "changing a dead node!");
1969       JVMState* jvms = unc->jvms();
1970       ciMethod* method = jvms->method();
1971       ciBytecodeStream iter(method);
1972 
1973       iter.force_bci(jvms->bci());
1974       assert(next_bci == iter.next_bci() || next_bci == iter.get_dest(), "wrong next_bci at unstable_if");
1975       Bytecodes::Code c = iter.cur_bc();
1976       Node* lhs = nullptr;
1977       Node* rhs = nullptr;
1978       if (c == Bytecodes::_if_acmpeq || c == Bytecodes::_if_acmpne) {
1979         lhs = unc->peek_operand(0);
1980         rhs = unc->peek_operand(1);
1981       } else if (c == Bytecodes::_ifnull || c == Bytecodes::_ifnonnull) {
1982         lhs = unc->peek_operand(0);
1983       }
1984 
1985       ResourceMark rm;
1986       const MethodLivenessResult& live_locals = method->liveness_at_bci(next_bci);
1987       assert(live_locals.is_valid(), "broken liveness info");
1988       int len = (int)live_locals.size();
1989 
1990       for (int i = 0; i < len; i++) {
1991         Node* local = unc->local(jvms, i);
1992         // kill local using the liveness of next_bci.
1993         // give up when the local looks like an operand to secure reexecution.
1994         if (!live_locals.at(i) && !local->is_top() && local != lhs && local!= rhs) {
1995           uint idx = jvms->locoff() + i;
1996 #ifdef ASSERT
1997           if (PrintOpto && Verbose) {
1998             tty->print("[unstable_if] kill local#%d: ", idx);
1999             local->dump();
2000             tty->cr();
2001           }
2002 #endif
2003           igvn.replace_input_of(unc, idx, top());
2004           modified = true;
2005         }
2006       }
2007     }
2008 
2009     // keep the mondified trap for late query
2010     if (modified) {
2011       trap->set_modified();
2012     } else {
2013       _unstable_if_traps.delete_at(i);
2014     }
2015   }
2016   igvn.optimize();
2017 }
2018 
2019 // StringOpts and late inlining of string methods
2020 void Compile::inline_string_calls(bool parse_time) {
2021   {
2022     // remove useless nodes to make the usage analysis simpler
2023     ResourceMark rm;
2024     PhaseRemoveUseless pru(initial_gvn(), *igvn_worklist());
2025   }
2026 
2027   {
2028     ResourceMark rm;
2029     print_method(PHASE_BEFORE_STRINGOPTS, 3);
2030     PhaseStringOpts pso(initial_gvn());
2031     print_method(PHASE_AFTER_STRINGOPTS, 3);
2032   }
2033 
2034   // now inline anything that we skipped the first time around
2035   if (!parse_time) {
2036     _late_inlines_pos = _late_inlines.length();
2037   }
2038 
2039   while (_string_late_inlines.length() > 0) {
2040     CallGenerator* cg = _string_late_inlines.pop();
2041     cg->do_late_inline();
2042     if (failing())  return;
2043   }
2044   _string_late_inlines.trunc_to(0);
2045 }
2046 
2047 // Late inlining of boxing methods
2048 void Compile::inline_boxing_calls(PhaseIterGVN& igvn) {
2049   if (_boxing_late_inlines.length() > 0) {
2050     assert(has_boxed_value(), "inconsistent");
2051 
2052     set_inlining_incrementally(true);
2053 
2054     igvn_worklist()->ensure_empty(); // should be done with igvn
2055 
2056     _late_inlines_pos = _late_inlines.length();
2057 
2058     while (_boxing_late_inlines.length() > 0) {
2059       CallGenerator* cg = _boxing_late_inlines.pop();
2060       cg->do_late_inline();
2061       if (failing())  return;
2062     }
2063     _boxing_late_inlines.trunc_to(0);
2064 
2065     inline_incrementally_cleanup(igvn);
2066 
2067     set_inlining_incrementally(false);
2068   }
2069 }
2070 
2071 bool Compile::inline_incrementally_one() {
2072   assert(IncrementalInline, "incremental inlining should be on");
2073   assert(_late_inlines.length() > 0, "should have been checked by caller");
2074 
2075   TracePhase tp(_t_incrInline_inline);
2076 
2077   set_inlining_progress(false);
2078   set_do_cleanup(false);
2079 
2080   for (int i = 0; i < _late_inlines.length(); i++) {
2081     _late_inlines_pos = i+1;
2082     CallGenerator* cg = _late_inlines.at(i);
2083     bool is_scheduled_for_igvn_before = C->igvn_worklist()->member(cg->call_node());
2084     bool does_dispatch = cg->is_virtual_late_inline() || cg->is_mh_late_inline();
2085     if (inlining_incrementally() || does_dispatch) { // a call can be either inlined or strength-reduced to a direct call
2086       if (should_stress_inlining()) {
2087         // randomly add repeated inline attempt if stress-inlining
2088         cg->call_node()->set_generator(cg);
2089         C->igvn_worklist()->push(cg->call_node());
2090         continue;
2091       }
2092       cg->do_late_inline();
2093       assert(_late_inlines.at(i) == cg, "no insertions before current position allowed");
2094       if (failing()) {
2095         return false;
2096       } else if (inlining_progress()) {
2097         _late_inlines_pos = i+1; // restore the position in case new elements were inserted
2098         print_method(PHASE_INCREMENTAL_INLINE_STEP, 3, cg->call_node());
2099         break; // process one call site at a time
2100       } else {
2101         bool is_scheduled_for_igvn_after = C->igvn_worklist()->member(cg->call_node());
2102         if (!is_scheduled_for_igvn_before && is_scheduled_for_igvn_after) {
2103           // Avoid potential infinite loop if node already in the IGVN list
2104           assert(false, "scheduled for IGVN during inlining attempt");
2105         } else {
2106           // Ensure call node has not disappeared from IGVN worklist during a failed inlining attempt
2107           assert(!is_scheduled_for_igvn_before || is_scheduled_for_igvn_after, "call node removed from IGVN list during inlining pass");
2108           cg->call_node()->set_generator(cg);
2109         }
2110       }
2111     } else {
2112       // Ignore late inline direct calls when inlining is not allowed.
2113       // They are left in the late inline list when node budget is exhausted until the list is fully drained.
2114     }
2115   }
2116   // Remove processed elements.
2117   _late_inlines.remove_till(_late_inlines_pos);
2118   _late_inlines_pos = 0;
2119 
2120   assert(inlining_progress() || _late_inlines.length() == 0, "no progress");
2121 
2122   bool needs_cleanup = do_cleanup() || over_inlining_cutoff();
2123 
2124   set_inlining_progress(false);
2125   set_do_cleanup(false);
2126 
2127   bool force_cleanup = directive()->IncrementalInlineForceCleanupOption;
2128   return (_late_inlines.length() > 0) && !needs_cleanup && !force_cleanup;
2129 }
2130 
2131 void Compile::inline_incrementally_cleanup(PhaseIterGVN& igvn) {
2132   {
2133     TracePhase tp(_t_incrInline_pru);
2134     ResourceMark rm;
2135     PhaseRemoveUseless pru(initial_gvn(), *igvn_worklist());
2136   }
2137   {
2138     TracePhase tp(_t_incrInline_igvn);
2139     igvn.reset();
2140     igvn.optimize();
2141     if (failing()) return;
2142   }
2143   print_method(PHASE_INCREMENTAL_INLINE_CLEANUP, 3);
2144 }
2145 
2146 template<typename E>
2147 static void shuffle_array(Compile& C, GrowableArray<E>& array) {
2148   if (array.length() < 2) {
2149     return;
2150   }
2151   for (uint i = array.length() - 1; i >= 1; i--) {
2152     uint j = C.random() % (i + 1);
2153     swap(array.at(i), array.at(j));
2154   }
2155 }
2156 
2157 void Compile::shuffle_late_inlines() {
2158   shuffle_array(*C, _late_inlines);
2159 }
2160 
2161 // Perform incremental inlining until bound on number of live nodes is reached
2162 void Compile::inline_incrementally(PhaseIterGVN& igvn) {
2163   TracePhase tp(_t_incrInline);
2164 
2165   set_inlining_incrementally(true);
2166   uint low_live_nodes = 0;
2167 
2168   if (StressIncrementalInlining) {
2169     shuffle_late_inlines();
2170   }
2171 
2172   while (_late_inlines.length() > 0) {
2173     if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2174       if (low_live_nodes < (uint)LiveNodeCountInliningCutoff * 8 / 10) {
2175         TracePhase tp(_t_incrInline_ideal);
2176         // PhaseIdealLoop is expensive so we only try it once we are
2177         // out of live nodes and we only try it again if the previous
2178         // helped got the number of nodes down significantly
2179         PhaseIdealLoop::optimize(igvn, LoopOptsNone);
2180         if (failing())  return;
2181         low_live_nodes = live_nodes();
2182         _major_progress = true;
2183       }
2184 
2185       if (live_nodes() > (uint)LiveNodeCountInliningCutoff) {
2186         bool do_print_inlining = print_inlining() || print_intrinsics();
2187         if (do_print_inlining || log() != nullptr) {
2188           // Print inlining message for candidates that we couldn't inline for lack of space.
2189           for (int i = 0; i < _late_inlines.length(); i++) {
2190             CallGenerator* cg = _late_inlines.at(i);
2191             const char* msg = "live nodes > LiveNodeCountInliningCutoff";
2192             if (do_print_inlining) {
2193               inline_printer()->record(cg->method(), cg->call_node()->jvms(), InliningResult::FAILURE, msg);
2194             }
2195             log_late_inline_failure(cg, msg);
2196           }
2197         }
2198         break; // finish
2199       }
2200     }
2201 
2202     igvn_worklist()->ensure_empty(); // should be done with igvn
2203 
2204     if (_late_inlines.length() == 0) {
2205       break; // no more progress
2206     }
2207 
2208     while (inline_incrementally_one()) {
2209       assert(!failing_internal() || failure_is_artificial(), "inconsistent");
2210     }
2211     if (failing())  return;
2212 
2213     inline_incrementally_cleanup(igvn);
2214 
2215     print_method(PHASE_INCREMENTAL_INLINE_STEP, 3);
2216 
2217     if (failing())  return;
2218   }
2219 
2220   igvn_worklist()->ensure_empty(); // should be done with igvn
2221 
2222   if (_string_late_inlines.length() > 0) {
2223     assert(has_stringbuilder(), "inconsistent");
2224 
2225     inline_string_calls(false);
2226 
2227     if (failing())  return;
2228 
2229     inline_incrementally_cleanup(igvn);
2230   }
2231 
2232   set_inlining_incrementally(false);
2233 }
2234 
2235 void Compile::process_late_inline_calls_no_inline(PhaseIterGVN& igvn) {
2236   // "inlining_incrementally() == false" is used to signal that no inlining is allowed
2237   // (see LateInlineVirtualCallGenerator::do_late_inline_check() for details).
2238   // Tracking and verification of modified nodes is disabled by setting "_modified_nodes == nullptr"
2239   // as if "inlining_incrementally() == true" were set.
2240   assert(inlining_incrementally() == false, "not allowed");
2241   assert(_modified_nodes == nullptr, "not allowed");
2242   assert(_late_inlines.length() > 0, "sanity");
2243 
2244   if (StressIncrementalInlining) {
2245     shuffle_late_inlines();
2246   }
2247 
2248   while (_late_inlines.length() > 0) {
2249     igvn_worklist()->ensure_empty(); // should be done with igvn
2250 
2251     while (inline_incrementally_one()) {
2252       assert(!failing_internal() || failure_is_artificial(), "inconsistent");
2253     }
2254     if (failing())  return;
2255 
2256     inline_incrementally_cleanup(igvn);
2257   }
2258 }
2259 
2260 bool Compile::optimize_loops(PhaseIterGVN& igvn, LoopOptsMode mode) {
2261   if (_loop_opts_cnt > 0) {
2262     while (major_progress() && (_loop_opts_cnt > 0)) {
2263       TracePhase tp(_t_idealLoop);
2264       PhaseIdealLoop::optimize(igvn, mode);
2265       _loop_opts_cnt--;
2266       if (failing())  return false;
2267       if (major_progress()) {
2268         print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
2269       }
2270     }
2271   }
2272   return true;
2273 }
2274 
2275 // Remove edges from "root" to each SafePoint at a backward branch.
2276 // They were inserted during parsing (see add_safepoint()) to make
2277 // infinite loops without calls or exceptions visible to root, i.e.,
2278 // useful.
2279 void Compile::remove_root_to_sfpts_edges(PhaseIterGVN& igvn) {
2280   Node *r = root();
2281   if (r != nullptr) {
2282     for (uint i = r->req(); i < r->len(); ++i) {
2283       Node *n = r->in(i);
2284       if (n != nullptr && n->is_SafePoint()) {
2285         r->rm_prec(i);
2286         if (n->outcnt() == 0) {
2287           igvn.remove_dead_node(n, PhaseIterGVN::NodeOrigin::Graph);
2288         }
2289         --i;
2290       }
2291     }
2292     // Parsing may have added top inputs to the root node (Path
2293     // leading to the Halt node proven dead). Make sure we get a
2294     // chance to clean them up.
2295     igvn._worklist.push(r);
2296     igvn.optimize();
2297   }
2298 }
2299 
2300 //------------------------------Optimize---------------------------------------
2301 // Given a graph, optimize it.
2302 void Compile::Optimize() {
2303   TracePhase tp(_t_optimizer);
2304 
2305 #ifndef PRODUCT
2306   if (env()->break_at_compile()) {
2307     BREAKPOINT;
2308   }
2309 
2310 #endif
2311 
2312   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
2313 #ifdef ASSERT
2314   bs->verify_gc_barriers(this, BarrierSetC2::BeforeOptimize);
2315 #endif
2316 
2317   ResourceMark rm;
2318 
2319   NOT_PRODUCT( verify_graph_edges(); )
2320 
2321   print_method(PHASE_AFTER_PARSING, 1);
2322 
2323  {
2324   // Iterative Global Value Numbering, including ideal transforms
2325   PhaseIterGVN igvn;
2326 #ifdef ASSERT
2327   _modified_nodes = new (comp_arena()) Unique_Node_List(comp_arena());
2328 #endif
2329   {
2330     TracePhase tp(_t_iterGVN);
2331     igvn.optimize(true);
2332   }
2333 
2334   if (failing())  return;
2335 
2336   print_method(PHASE_ITER_GVN1, 2);
2337 
2338   process_for_unstable_if_traps(igvn);
2339 
2340   if (failing())  return;
2341 
2342   inline_incrementally(igvn);
2343 
2344   print_method(PHASE_INCREMENTAL_INLINE, 2);
2345 
2346   if (failing())  return;
2347 
2348   if (eliminate_boxing()) {
2349     // Inline valueOf() methods now.
2350     inline_boxing_calls(igvn);
2351 
2352     if (failing())  return;
2353 
2354     if (AlwaysIncrementalInline || StressIncrementalInlining) {
2355       inline_incrementally(igvn);
2356     }
2357 
2358     print_method(PHASE_INCREMENTAL_BOXING_INLINE, 2);
2359 
2360     if (failing())  return;
2361   }
2362 
2363   // Remove the speculative part of types and clean up the graph from
2364   // the extra CastPP nodes whose only purpose is to carry them. Do
2365   // that early so that optimizations are not disrupted by the extra
2366   // CastPP nodes.
2367   remove_speculative_types(igvn);
2368 
2369   if (failing())  return;
2370 
2371   // No more new expensive nodes will be added to the list from here
2372   // so keep only the actual candidates for optimizations.
2373   cleanup_expensive_nodes(igvn);
2374 
2375   if (failing())  return;
2376 
2377   assert(EnableVectorSupport || !has_vbox_nodes(), "sanity");
2378   if (EnableVectorSupport && has_vbox_nodes()) {
2379     TracePhase tp(_t_vector);
2380     PhaseVector pv(igvn);
2381     pv.optimize_vector_boxes();
2382     if (failing())  return;
2383     print_method(PHASE_ITER_GVN_AFTER_VECTOR, 2);
2384   }
2385   assert(!has_vbox_nodes(), "sanity");
2386 
2387   if (!failing() && RenumberLiveNodes && live_nodes() + NodeLimitFudgeFactor < unique()) {
2388     Compile::TracePhase tp(_t_renumberLive);
2389     igvn_worklist()->ensure_empty(); // should be done with igvn
2390     {
2391       ResourceMark rm;
2392       PhaseRenumberLive prl(initial_gvn(), *igvn_worklist());
2393     }
2394     igvn.reset();
2395     igvn.optimize(true);
2396     if (failing()) return;
2397   }
2398 
2399   // Now that all inlining is over and no PhaseRemoveUseless will run, cut edge from root to loop
2400   // safepoints
2401   remove_root_to_sfpts_edges(igvn);
2402 
2403   if (failing())  return;
2404 
2405   _print_phase_loop_opts = has_loops();
2406   if (_print_phase_loop_opts) {
2407     print_method(PHASE_BEFORE_LOOP_OPTS, 2);
2408   }
2409 
2410   // Perform escape analysis
2411   if (do_escape_analysis() && ConnectionGraph::has_candidates(this)) {
2412     if (has_loops()) {
2413       // Cleanup graph (remove dead nodes).
2414       TracePhase tp(_t_idealLoop);
2415       PhaseIdealLoop::optimize(igvn, LoopOptsMaxUnroll);
2416       if (failing())  return;
2417     }
2418     bool progress;
2419     print_method(PHASE_PHASEIDEAL_BEFORE_EA, 2);
2420     do {
2421       ConnectionGraph::do_analysis(this, &igvn);
2422 
2423       if (failing())  return;
2424 
2425       int mcount = macro_count(); // Record number of allocations and locks before IGVN
2426 
2427       // Optimize out fields loads from scalar replaceable allocations.
2428       igvn.optimize(true);
2429       print_method(PHASE_ITER_GVN_AFTER_EA, 2);
2430 
2431       if (failing()) return;
2432 
2433       if (congraph() != nullptr && macro_count() > 0) {
2434         TracePhase tp(_t_macroEliminate);
2435         PhaseMacroExpand mexp(igvn);
2436         mexp.eliminate_macro_nodes();
2437         if (failing()) return;
2438         print_method(PHASE_AFTER_MACRO_ELIMINATION, 2);
2439 
2440         igvn.set_delay_transform(false);
2441         igvn.optimize();
2442         if (failing()) return;
2443 
2444         print_method(PHASE_ITER_GVN_AFTER_ELIMINATION, 2);
2445       }
2446 
2447       ConnectionGraph::verify_ram_nodes(this, root());
2448       if (failing())  return;
2449 
2450       progress = do_iterative_escape_analysis() &&
2451                  (macro_count() < mcount) &&
2452                  ConnectionGraph::has_candidates(this);
2453       // Try again if candidates exist and made progress
2454       // by removing some allocations and/or locks.
2455     } while (progress);
2456   }
2457 
2458   // Loop transforms on the ideal graph.  Range Check Elimination,
2459   // peeling, unrolling, etc.
2460 
2461   // Set loop opts counter
2462   if((_loop_opts_cnt > 0) && (has_loops() || has_split_ifs())) {
2463     {
2464       TracePhase tp(_t_idealLoop);
2465       PhaseIdealLoop::optimize(igvn, LoopOptsDefault);
2466       _loop_opts_cnt--;
2467       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP1, 2);
2468       if (failing())  return;
2469     }
2470     // Loop opts pass if partial peeling occurred in previous pass
2471     if(PartialPeelLoop && major_progress() && (_loop_opts_cnt > 0)) {
2472       TracePhase tp(_t_idealLoop);
2473       PhaseIdealLoop::optimize(igvn, LoopOptsSkipSplitIf);
2474       _loop_opts_cnt--;
2475       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP2, 2);
2476       if (failing())  return;
2477     }
2478     // Loop opts pass for loop-unrolling before CCP
2479     if(major_progress() && (_loop_opts_cnt > 0)) {
2480       TracePhase tp(_t_idealLoop);
2481       PhaseIdealLoop::optimize(igvn, LoopOptsSkipSplitIf);
2482       _loop_opts_cnt--;
2483       if (major_progress()) print_method(PHASE_PHASEIDEALLOOP3, 2);
2484     }
2485     if (!failing()) {
2486       // Verify that last round of loop opts produced a valid graph
2487       PhaseIdealLoop::verify(igvn);
2488     }
2489   }
2490   if (failing())  return;
2491 
2492   // Conditional Constant Propagation;
2493   print_method(PHASE_BEFORE_CCP1, 2);
2494   PhaseCCP ccp( &igvn );
2495   assert( true, "Break here to ccp.dump_nodes_and_types(_root,999,1)");
2496   {
2497     TracePhase tp(_t_ccp);
2498     ccp.do_transform();
2499   }
2500   print_method(PHASE_CCP1, 2);
2501 
2502   assert( true, "Break here to ccp.dump_old2new_map()");
2503 
2504   // Iterative Global Value Numbering, including ideal transforms
2505   {
2506     TracePhase tp(_t_iterGVN2);
2507     igvn.reset_from_igvn(&ccp);
2508     igvn.optimize(true);
2509   }
2510   print_method(PHASE_ITER_GVN2, 2);
2511 
2512   if (failing())  return;
2513 
2514   // Loop transforms on the ideal graph.  Range Check Elimination,
2515   // peeling, unrolling, etc.
2516   if (!optimize_loops(igvn, LoopOptsDefault)) {
2517     return;
2518   }
2519 
2520   C->clear_major_progress(); // ensure that major progress is now clear
2521 
2522   process_for_post_loop_opts_igvn(igvn);
2523 
2524   if (failing())  return;
2525 
2526   // Once loop optimizations are over, it is safe to get rid of all reachability fence nodes and
2527   // migrate reachability edges to safepoints.
2528   if (OptimizeReachabilityFences && _reachability_fences.length() > 0) {
2529     TracePhase tp1(_t_idealLoop);
2530     TracePhase tp2(_t_reachability);
2531     PhaseIdealLoop::optimize(igvn, PostLoopOptsExpandReachabilityFences);
2532     print_method(PHASE_EXPAND_REACHABILITY_FENCES, 2);
2533     if (failing())  return;
2534     assert(_reachability_fences.length() == 0 || PreserveReachabilityFencesOnConstants, "no RF nodes allowed");
2535   }
2536 
2537   process_for_merge_stores_igvn(igvn);
2538 
2539   if (failing())  return;
2540 
2541 #ifdef ASSERT
2542   bs->verify_gc_barriers(this, BarrierSetC2::BeforeMacroExpand);
2543 #endif
2544 
2545   {
2546     TracePhase tp(_t_macroExpand);
2547     print_method(PHASE_BEFORE_MACRO_EXPANSION, 3);
2548     PhaseMacroExpand  mex(igvn);
2549     // Do not allow new macro nodes once we start to eliminate and expand
2550     C->reset_allow_macro_nodes();
2551     // Last attempt to eliminate macro nodes before expand
2552     mex.eliminate_macro_nodes();
2553     if (failing()) {
2554       return;
2555     }
2556     mex.eliminate_opaque_looplimit_macro_nodes();
2557     if (failing()) {
2558       return;
2559     }
2560     print_method(PHASE_AFTER_MACRO_ELIMINATION, 2);
2561     if (mex.expand_macro_nodes()) {
2562       assert(failing(), "must bail out w/ explicit message");
2563       return;
2564     }
2565     print_method(PHASE_AFTER_MACRO_EXPANSION, 2);
2566   }
2567 
2568   {
2569     TracePhase tp(_t_barrierExpand);
2570     if (bs->expand_barriers(this, igvn)) {
2571       assert(failing(), "must bail out w/ explicit message");
2572       return;
2573     }
2574     print_method(PHASE_BARRIER_EXPANSION, 2);
2575   }
2576 
2577   if (C->max_vector_size() > 0) {
2578     C->optimize_logic_cones(igvn);
2579     igvn.optimize();
2580     if (failing()) return;
2581   }
2582 
2583   DEBUG_ONLY( _modified_nodes = nullptr; )
2584 
2585   assert(igvn._worklist.size() == 0, "not empty");
2586 
2587   if (_late_inlines.length() > 0) {
2588     // More opportunities to optimize virtual and MH calls.
2589     // Though it's maybe too late to perform inlining, strength-reducing them to direct calls is still an option.
2590     process_late_inline_calls_no_inline(igvn);
2591     if (failing())  return;
2592   }
2593   assert(_late_inlines.length() == 0, "late inline queue must be drained");
2594  } // (End scope of igvn; run destructor if necessary for asserts.)
2595 
2596  check_no_dead_use();
2597 
2598  // We will never use the NodeHash table any more. Clear it so that final_graph_reshaping does not have
2599  // to remove hashes to unlock nodes for modifications.
2600  C->node_hash()->clear();
2601 
2602  // A method with only infinite loops has no edges entering loops from root
2603  {
2604    TracePhase tp(_t_graphReshaping);
2605    if (final_graph_reshaping()) {
2606      assert(failing(), "must bail out w/ explicit message");
2607      return;
2608    }
2609  }
2610 
2611  print_method(PHASE_OPTIMIZE_FINISHED, 2);
2612  DEBUG_ONLY(set_phase_optimize_finished();)
2613 }
2614 
2615 #ifdef ASSERT
2616 void Compile::check_no_dead_use() const {
2617   ResourceMark rm;
2618   Unique_Node_List wq;
2619   wq.push(root());
2620   for (uint i = 0; i < wq.size(); ++i) {
2621     Node* n = wq.at(i);
2622     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++) {
2623       Node* u = n->fast_out(j);
2624       if (u->outcnt() == 0 && !u->is_Con()) {
2625         u->dump();
2626         fatal("no reachable node should have no use");
2627       }
2628       wq.push(u);
2629     }
2630   }
2631 }
2632 #endif
2633 
2634 void Compile::inline_vector_reboxing_calls() {
2635   if (C->_vector_reboxing_late_inlines.length() > 0) {
2636     _late_inlines_pos = C->_late_inlines.length();
2637     while (_vector_reboxing_late_inlines.length() > 0) {
2638       CallGenerator* cg = _vector_reboxing_late_inlines.pop();
2639       cg->do_late_inline();
2640       if (failing())  return;
2641       print_method(PHASE_INLINE_VECTOR_REBOX, 3, cg->call_node());
2642     }
2643     _vector_reboxing_late_inlines.trunc_to(0);
2644   }
2645 }
2646 
2647 bool Compile::has_vbox_nodes() {
2648   if (C->_vector_reboxing_late_inlines.length() > 0) {
2649     return true;
2650   }
2651   for (int macro_idx = C->macro_count() - 1; macro_idx >= 0; macro_idx--) {
2652     Node * n = C->macro_node(macro_idx);
2653     assert(n->is_macro(), "only macro nodes expected here");
2654     if (n->Opcode() == Op_VectorUnbox || n->Opcode() == Op_VectorBox || n->Opcode() == Op_VectorBoxAllocate) {
2655       return true;
2656     }
2657   }
2658   return false;
2659 }
2660 
2661 //---------------------------- Bitwise operation packing optimization ---------------------------
2662 
2663 static bool is_vector_unary_bitwise_op(Node* n) {
2664   return n->Opcode() == Op_XorV &&
2665          VectorNode::is_vector_bitwise_not_pattern(n);
2666 }
2667 
2668 static bool is_vector_binary_bitwise_op(Node* n) {
2669   switch (n->Opcode()) {
2670     case Op_AndV:
2671     case Op_OrV:
2672       return true;
2673 
2674     case Op_XorV:
2675       return !is_vector_unary_bitwise_op(n);
2676 
2677     default:
2678       return false;
2679   }
2680 }
2681 
2682 static bool is_vector_ternary_bitwise_op(Node* n) {
2683   return n->Opcode() == Op_MacroLogicV;
2684 }
2685 
2686 static bool is_vector_bitwise_op(Node* n) {
2687   return is_vector_unary_bitwise_op(n)  ||
2688          is_vector_binary_bitwise_op(n) ||
2689          is_vector_ternary_bitwise_op(n);
2690 }
2691 
2692 static bool is_vector_bitwise_cone_root(Node* n) {
2693   if (n->bottom_type()->isa_vectmask() || !is_vector_bitwise_op(n)) {
2694     return false;
2695   }
2696   for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2697     if (is_vector_bitwise_op(n->fast_out(i))) {
2698       return false;
2699     }
2700   }
2701   return true;
2702 }
2703 
2704 static uint collect_unique_inputs(Node* n, Unique_Node_List& inputs) {
2705   uint cnt = 0;
2706   if (is_vector_bitwise_op(n)) {
2707     uint inp_cnt = n->is_predicated_vector() ? n->req()-1 : n->req();
2708     if (VectorNode::is_vector_bitwise_not_pattern(n)) {
2709       for (uint i = 1; i < inp_cnt; i++) {
2710         Node* in = n->in(i);
2711         bool skip = VectorNode::is_all_ones_vector(in);
2712         if (!skip && !inputs.member(in)) {
2713           inputs.push(in);
2714           cnt++;
2715         }
2716       }
2717       assert(cnt <= 1, "not unary");
2718     } else {
2719       uint last_req = inp_cnt;
2720       if (is_vector_ternary_bitwise_op(n)) {
2721         last_req = inp_cnt - 1; // skip last input
2722       }
2723       for (uint i = 1; i < last_req; i++) {
2724         Node* def = n->in(i);
2725         if (!inputs.member(def)) {
2726           inputs.push(def);
2727           cnt++;
2728         }
2729       }
2730     }
2731   } else { // not a bitwise operations
2732     if (!inputs.member(n)) {
2733       inputs.push(n);
2734       cnt++;
2735     }
2736   }
2737   return cnt;
2738 }
2739 
2740 void Compile::collect_logic_cone_roots(Unique_Node_List& list) {
2741   Unique_Node_List useful_nodes;
2742   C->identify_useful_nodes(useful_nodes);
2743 
2744   for (uint i = 0; i < useful_nodes.size(); i++) {
2745     Node* n = useful_nodes.at(i);
2746     if (is_vector_bitwise_cone_root(n)) {
2747       list.push(n);
2748     }
2749   }
2750 }
2751 
2752 Node* Compile::xform_to_MacroLogicV(PhaseIterGVN& igvn,
2753                                     const TypeVect* vt,
2754                                     Unique_Node_List& partition,
2755                                     Unique_Node_List& inputs) {
2756   assert(partition.size() == 2 || partition.size() == 3, "not supported");
2757   assert(inputs.size()    == 2 || inputs.size()    == 3, "not supported");
2758   assert(Matcher::match_rule_supported_vector(Op_MacroLogicV, vt->length(), vt->element_basic_type()), "not supported");
2759 
2760   Node* in1 = inputs.at(0);
2761   Node* in2 = inputs.at(1);
2762   Node* in3 = (inputs.size() == 3 ? inputs.at(2) : in2);
2763 
2764   uint func = compute_truth_table(partition, inputs);
2765 
2766   Node* pn = partition.at(partition.size() - 1);
2767   Node* mask = pn->is_predicated_vector() ? pn->in(pn->req()-1) : nullptr;
2768   return igvn.transform(MacroLogicVNode::make(igvn, in1, in2, in3, mask, func, vt));
2769 }
2770 
2771 static uint extract_bit(uint func, uint pos) {
2772   return (func & (1 << pos)) >> pos;
2773 }
2774 
2775 //
2776 //  A macro logic node represents a truth table. It has 4 inputs,
2777 //  First three inputs corresponds to 3 columns of a truth table
2778 //  and fourth input captures the logic function.
2779 //
2780 //  eg.  fn = (in1 AND in2) OR in3;
2781 //
2782 //      MacroNode(in1,in2,in3,fn)
2783 //
2784 //  -----------------
2785 //  in1 in2 in3  fn
2786 //  -----------------
2787 //  0    0   0    0
2788 //  0    0   1    1
2789 //  0    1   0    0
2790 //  0    1   1    1
2791 //  1    0   0    0
2792 //  1    0   1    1
2793 //  1    1   0    1
2794 //  1    1   1    1
2795 //
2796 
2797 uint Compile::eval_macro_logic_op(uint func, uint in1 , uint in2, uint in3) {
2798   int res = 0;
2799   for (int i = 0; i < 8; i++) {
2800     int bit1 = extract_bit(in1, i);
2801     int bit2 = extract_bit(in2, i);
2802     int bit3 = extract_bit(in3, i);
2803 
2804     int func_bit_pos = (bit1 << 2 | bit2 << 1 | bit3);
2805     int func_bit = extract_bit(func, func_bit_pos);
2806 
2807     res |= func_bit << i;
2808   }
2809   return res;
2810 }
2811 
2812 static uint eval_operand(Node* n, HashTable<Node*,uint>& eval_map) {
2813   assert(n != nullptr, "");
2814   assert(eval_map.contains(n), "absent");
2815   return *(eval_map.get(n));
2816 }
2817 
2818 static void eval_operands(Node* n,
2819                           uint& func1, uint& func2, uint& func3,
2820                           HashTable<Node*,uint>& eval_map) {
2821   assert(is_vector_bitwise_op(n), "");
2822 
2823   if (is_vector_unary_bitwise_op(n)) {
2824     Node* opnd = n->in(1);
2825     if (VectorNode::is_vector_bitwise_not_pattern(n) && VectorNode::is_all_ones_vector(opnd)) {
2826       opnd = n->in(2);
2827     }
2828     func1 = eval_operand(opnd, eval_map);
2829   } else if (is_vector_binary_bitwise_op(n)) {
2830     func1 = eval_operand(n->in(1), eval_map);
2831     func2 = eval_operand(n->in(2), eval_map);
2832   } else {
2833     assert(is_vector_ternary_bitwise_op(n), "unknown operation");
2834     func1 = eval_operand(n->in(1), eval_map);
2835     func2 = eval_operand(n->in(2), eval_map);
2836     func3 = eval_operand(n->in(3), eval_map);
2837   }
2838 }
2839 
2840 uint Compile::compute_truth_table(Unique_Node_List& partition, Unique_Node_List& inputs) {
2841   assert(inputs.size() <= 3, "sanity");
2842   ResourceMark rm;
2843   uint res = 0;
2844   HashTable<Node*,uint> eval_map;
2845 
2846   // Populate precomputed functions for inputs.
2847   // Each input corresponds to one column of 3 input truth-table.
2848   uint input_funcs[] = { 0xAA,   // (_, _, c) -> c
2849                          0xCC,   // (_, b, _) -> b
2850                          0xF0 }; // (a, _, _) -> a
2851   for (uint i = 0; i < inputs.size(); i++) {
2852     eval_map.put(inputs.at(i), input_funcs[2-i]);
2853   }
2854 
2855   for (uint i = 0; i < partition.size(); i++) {
2856     Node* n = partition.at(i);
2857 
2858     uint func1 = 0, func2 = 0, func3 = 0;
2859     eval_operands(n, func1, func2, func3, eval_map);
2860 
2861     switch (n->Opcode()) {
2862       case Op_OrV:
2863         assert(func3 == 0, "not binary");
2864         res = func1 | func2;
2865         break;
2866       case Op_AndV:
2867         assert(func3 == 0, "not binary");
2868         res = func1 & func2;
2869         break;
2870       case Op_XorV:
2871         if (VectorNode::is_vector_bitwise_not_pattern(n)) {
2872           assert(func2 == 0 && func3 == 0, "not unary");
2873           res = (~func1) & 0xFF;
2874         } else {
2875           assert(func3 == 0, "not binary");
2876           res = func1 ^ func2;
2877         }
2878         break;
2879       case Op_MacroLogicV:
2880         // Ordering of inputs may change during evaluation of sub-tree
2881         // containing MacroLogic node as a child node, thus a re-evaluation
2882         // makes sure that function is evaluated in context of current
2883         // inputs.
2884         res = eval_macro_logic_op(n->in(4)->get_int(), func1, func2, func3);
2885         break;
2886 
2887       default: assert(false, "not supported: %s", n->Name());
2888     }
2889     assert(res <= 0xFF, "invalid");
2890     eval_map.put(n, res);
2891   }
2892   return res;
2893 }
2894 
2895 // Criteria under which nodes gets packed into a macro logic node:-
2896 //  1) Parent and both child nodes are all unmasked or masked with
2897 //     same predicates.
2898 //  2) Masked parent can be packed with left child if it is predicated
2899 //     and both have same predicates.
2900 //  3) Masked parent can be packed with right child if its un-predicated
2901 //     or has matching predication condition.
2902 //  4) An unmasked parent can be packed with an unmasked child.
2903 bool Compile::compute_logic_cone(Node* n, Unique_Node_List& partition, Unique_Node_List& inputs) {
2904   assert(partition.size() == 0, "not empty");
2905   assert(inputs.size() == 0, "not empty");
2906   if (is_vector_ternary_bitwise_op(n)) {
2907     return false;
2908   }
2909 
2910   bool is_unary_op = is_vector_unary_bitwise_op(n);
2911   if (is_unary_op) {
2912     assert(collect_unique_inputs(n, inputs) == 1, "not unary");
2913     return false; // too few inputs
2914   }
2915 
2916   bool pack_left_child = true;
2917   bool pack_right_child = true;
2918 
2919   bool left_child_LOP = is_vector_bitwise_op(n->in(1));
2920   bool right_child_LOP = is_vector_bitwise_op(n->in(2));
2921 
2922   int left_child_input_cnt = 0;
2923   int right_child_input_cnt = 0;
2924 
2925   bool parent_is_predicated = n->is_predicated_vector();
2926   bool left_child_predicated = n->in(1)->is_predicated_vector();
2927   bool right_child_predicated = n->in(2)->is_predicated_vector();
2928 
2929   Node* parent_pred = parent_is_predicated ? n->in(n->req()-1) : nullptr;
2930   Node* left_child_pred = left_child_predicated ? n->in(1)->in(n->in(1)->req()-1) : nullptr;
2931   Node* right_child_pred = right_child_predicated ? n->in(1)->in(n->in(1)->req()-1) : nullptr;
2932 
2933   do {
2934     if (pack_left_child && left_child_LOP &&
2935         ((!parent_is_predicated && !left_child_predicated) ||
2936         ((parent_is_predicated && left_child_predicated &&
2937           parent_pred == left_child_pred)))) {
2938        partition.push(n->in(1));
2939        left_child_input_cnt = collect_unique_inputs(n->in(1), inputs);
2940     } else {
2941        inputs.push(n->in(1));
2942        left_child_input_cnt = 1;
2943     }
2944 
2945     if (pack_right_child && right_child_LOP &&
2946         (!right_child_predicated ||
2947          (right_child_predicated && parent_is_predicated &&
2948           parent_pred == right_child_pred))) {
2949        partition.push(n->in(2));
2950        right_child_input_cnt = collect_unique_inputs(n->in(2), inputs);
2951     } else {
2952        inputs.push(n->in(2));
2953        right_child_input_cnt = 1;
2954     }
2955 
2956     if (inputs.size() > 3) {
2957       assert(partition.size() > 0, "");
2958       inputs.clear();
2959       partition.clear();
2960       if (left_child_input_cnt > right_child_input_cnt) {
2961         pack_left_child = false;
2962       } else {
2963         pack_right_child = false;
2964       }
2965     } else {
2966       break;
2967     }
2968   } while(true);
2969 
2970   if(partition.size()) {
2971     partition.push(n);
2972   }
2973 
2974   return (partition.size() == 2 || partition.size() == 3) &&
2975          (inputs.size()    == 2 || inputs.size()    == 3);
2976 }
2977 
2978 void Compile::process_logic_cone_root(PhaseIterGVN &igvn, Node *n, VectorSet &visited) {
2979   assert(is_vector_bitwise_op(n), "not a root");
2980 
2981   visited.set(n->_idx);
2982 
2983   // 1) Do a DFS walk over the logic cone.
2984   for (uint i = 1; i < n->req(); i++) {
2985     Node* in = n->in(i);
2986     if (!visited.test(in->_idx) && is_vector_bitwise_op(in)) {
2987       process_logic_cone_root(igvn, in, visited);
2988     }
2989   }
2990 
2991   // 2) Bottom up traversal: Merge node[s] with
2992   // the parent to form macro logic node.
2993   Unique_Node_List partition;
2994   Unique_Node_List inputs;
2995   if (compute_logic_cone(n, partition, inputs)) {
2996     const TypeVect* vt = n->bottom_type()->is_vect();
2997     Node* pn = partition.at(partition.size() - 1);
2998     Node* mask = pn->is_predicated_vector() ? pn->in(pn->req()-1) : nullptr;
2999     if (mask == nullptr ||
3000         Matcher::match_rule_supported_vector_masked(Op_MacroLogicV, vt->length(), vt->element_basic_type())) {
3001       Node* macro_logic = xform_to_MacroLogicV(igvn, vt, partition, inputs);
3002       VectorNode::trace_new_vector(macro_logic, "MacroLogic");
3003       igvn.replace_node(n, macro_logic);
3004     }
3005   }
3006 }
3007 
3008 void Compile::optimize_logic_cones(PhaseIterGVN &igvn) {
3009   ResourceMark rm;
3010   if (Matcher::match_rule_supported(Op_MacroLogicV)) {
3011     Unique_Node_List list;
3012     collect_logic_cone_roots(list);
3013 
3014     while (list.size() > 0) {
3015       Node* n = list.pop();
3016       const TypeVect* vt = n->bottom_type()->is_vect();
3017       bool supported = Matcher::match_rule_supported_vector(Op_MacroLogicV, vt->length(), vt->element_basic_type());
3018       if (supported) {
3019         VectorSet visited(comp_arena());
3020         process_logic_cone_root(igvn, n, visited);
3021       }
3022     }
3023   }
3024 }
3025 
3026 //------------------------------Code_Gen---------------------------------------
3027 // Given a graph, generate code for it
3028 void Compile::Code_Gen() {
3029   if (failing()) {
3030     return;
3031   }
3032 
3033   // Perform instruction selection.  You might think we could reclaim Matcher
3034   // memory PDQ, but actually the Matcher is used in generating spill code.
3035   // Internals of the Matcher (including some VectorSets) must remain live
3036   // for awhile - thus I cannot reclaim Matcher memory lest a VectorSet usage
3037   // set a bit in reclaimed memory.
3038 
3039   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
3040   // nodes.  Mapping is only valid at the root of each matched subtree.
3041   NOT_PRODUCT( verify_graph_edges(); )
3042 
3043   Matcher matcher;
3044   _matcher = &matcher;
3045   {
3046     TracePhase tp(_t_matcher);
3047     matcher.match();
3048     if (failing()) {
3049       return;
3050     }
3051   }
3052   // In debug mode can dump m._nodes.dump() for mapping of ideal to machine
3053   // nodes.  Mapping is only valid at the root of each matched subtree.
3054   NOT_PRODUCT( verify_graph_edges(); )
3055 
3056   // If you have too many nodes, or if matching has failed, bail out
3057   check_node_count(0, "out of nodes matching instructions");
3058   if (failing()) {
3059     return;
3060   }
3061 
3062   print_method(PHASE_MATCHING, 2);
3063 
3064   // Build a proper-looking CFG
3065   PhaseCFG cfg(node_arena(), root(), matcher);
3066   if (failing()) {
3067     return;
3068   }
3069   _cfg = &cfg;
3070   {
3071     TracePhase tp(_t_scheduler);
3072     bool success = cfg.do_global_code_motion();
3073     if (!success) {
3074       return;
3075     }
3076 
3077     print_method(PHASE_GLOBAL_CODE_MOTION, 2);
3078     NOT_PRODUCT( verify_graph_edges(); )
3079     cfg.verify();
3080     if (failing()) {
3081       return;
3082     }
3083   }
3084 
3085   PhaseChaitin regalloc(unique(), cfg, matcher, false);
3086   _regalloc = &regalloc;
3087   {
3088     TracePhase tp(_t_registerAllocation);
3089     // Perform register allocation.  After Chaitin, use-def chains are
3090     // no longer accurate (at spill code) and so must be ignored.
3091     // Node->LRG->reg mappings are still accurate.
3092     _regalloc->Register_Allocate();
3093 
3094     // Bail out if the allocator builds too many nodes
3095     if (failing()) {
3096       return;
3097     }
3098 
3099     print_method(PHASE_REGISTER_ALLOCATION, 2);
3100   }
3101 
3102   // Prior to register allocation we kept empty basic blocks in case the
3103   // the allocator needed a place to spill.  After register allocation we
3104   // are not adding any new instructions.  If any basic block is empty, we
3105   // can now safely remove it.
3106   {
3107     TracePhase tp(_t_blockOrdering);
3108     cfg.remove_empty_blocks();
3109     if (do_freq_based_layout()) {
3110       PhaseBlockLayout layout(cfg);
3111     } else {
3112       cfg.set_loop_alignment();
3113     }
3114     cfg.fixup_flow();
3115     cfg.remove_unreachable_blocks();
3116     cfg.verify_dominator_tree();
3117     print_method(PHASE_BLOCK_ORDERING, 3);
3118   }
3119 
3120   // Apply peephole optimizations
3121   if( OptoPeephole ) {
3122     TracePhase tp(_t_peephole);
3123     PhasePeephole peep( _regalloc, cfg);
3124     peep.do_transform();
3125     print_method(PHASE_PEEPHOLE, 3);
3126   }
3127 
3128   // Do late expand if CPU requires this.
3129   if (Matcher::require_postalloc_expand) {
3130     TracePhase tp(_t_postalloc_expand);
3131     cfg.postalloc_expand(_regalloc);
3132     print_method(PHASE_POSTALLOC_EXPAND, 3);
3133   }
3134 
3135 #ifdef ASSERT
3136   {
3137     CompilationMemoryStatistic::do_test_allocations();
3138     if (failing()) return;
3139   }
3140 #endif
3141 
3142   // Convert Nodes to instruction bits in a buffer
3143   {
3144     TracePhase tp(_t_output);
3145     PhaseOutput output;
3146     output.Output();
3147     if (failing())  return;
3148     output.install();
3149     print_method(PHASE_FINAL_CODE, 1); // Compile::_output is not null here
3150   }
3151 
3152   // He's dead, Jim.
3153   _cfg     = (PhaseCFG*)((intptr_t)0xdeadbeef);
3154   _regalloc = (PhaseChaitin*)((intptr_t)0xdeadbeef);
3155 }
3156 
3157 //------------------------------Final_Reshape_Counts---------------------------
3158 // This class defines counters to help identify when a method
3159 // may/must be executed using hardware with only 24-bit precision.
3160 struct Final_Reshape_Counts : public StackObj {
3161   int  _call_count;             // count non-inlined 'common' calls
3162   int  _float_count;            // count float ops requiring 24-bit precision
3163   int  _double_count;           // count double ops requiring more precision
3164   int  _java_call_count;        // count non-inlined 'java' calls
3165   int  _inner_loop_count;       // count loops which need alignment
3166   VectorSet _visited;           // Visitation flags
3167   Node_List _tests;             // Set of IfNodes & PCTableNodes
3168 
3169   Final_Reshape_Counts() :
3170     _call_count(0), _float_count(0), _double_count(0),
3171     _java_call_count(0), _inner_loop_count(0) { }
3172 
3173   void inc_call_count  () { _call_count  ++; }
3174   void inc_float_count () { _float_count ++; }
3175   void inc_double_count() { _double_count++; }
3176   void inc_java_call_count() { _java_call_count++; }
3177   void inc_inner_loop_count() { _inner_loop_count++; }
3178 
3179   int  get_call_count  () const { return _call_count  ; }
3180   int  get_float_count () const { return _float_count ; }
3181   int  get_double_count() const { return _double_count; }
3182   int  get_java_call_count() const { return _java_call_count; }
3183   int  get_inner_loop_count() const { return _inner_loop_count; }
3184 };
3185 
3186 //------------------------------final_graph_reshaping_impl----------------------
3187 // Implement items 1-5 from final_graph_reshaping below.
3188 void Compile::final_graph_reshaping_impl(Node *n, Final_Reshape_Counts& frc, Unique_Node_List& dead_nodes) {
3189 
3190   if ( n->outcnt() == 0 ) return; // dead node
3191   uint nop = n->Opcode();
3192 
3193   // Check for 2-input instruction with "last use" on right input.
3194   // Swap to left input.  Implements item (2).
3195   if( n->req() == 3 &&          // two-input instruction
3196       n->in(1)->outcnt() > 1 && // left use is NOT a last use
3197       (!n->in(1)->is_Phi() || n->in(1)->in(2) != n) && // it is not data loop
3198       n->in(2)->outcnt() == 1 &&// right use IS a last use
3199       !n->in(2)->is_Con() ) {   // right use is not a constant
3200     // Check for commutative opcode
3201     switch( nop ) {
3202     case Op_AddI:  case Op_AddF:  case Op_AddD:  case Op_AddHF:  case Op_AddL:
3203     case Op_MaxI:  case Op_MaxL:  case Op_MaxF:  case Op_MaxD:
3204     case Op_MinI:  case Op_MinL:  case Op_MinF:  case Op_MinD:
3205     case Op_MulI:  case Op_MulF:  case Op_MulD:  case Op_MulHF:  case Op_MulL:
3206     case Op_AndL:  case Op_XorL:  case Op_OrL:
3207     case Op_AndI:  case Op_XorI:  case Op_OrI: {
3208       // Move "last use" input to left by swapping inputs
3209       n->swap_edges(1, 2);
3210       break;
3211     }
3212     default:
3213       break;
3214     }
3215   }
3216 
3217 #ifdef ASSERT
3218   if( n->is_Mem() ) {
3219     int alias_idx = get_alias_index(n->as_Mem()->adr_type());
3220     assert( n->in(0) != nullptr || alias_idx != Compile::AliasIdxRaw ||
3221             // oop will be recorded in oop map if load crosses safepoint
3222             (n->is_Load() && (n->as_Load()->bottom_type()->isa_oopptr() ||
3223                               LoadNode::is_immutable_value(n->in(MemNode::Address)))),
3224             "raw memory operations should have control edge");
3225   }
3226   if (n->is_MemBar()) {
3227     MemBarNode* mb = n->as_MemBar();
3228     if (mb->trailing_store() || mb->trailing_load_store()) {
3229       assert(mb->leading_membar()->trailing_membar() == mb, "bad membar pair");
3230       Node* mem = BarrierSet::barrier_set()->barrier_set_c2()->step_over_gc_barrier(mb->in(MemBarNode::Precedent));
3231       assert((mb->trailing_store() && mem->is_Store() && mem->as_Store()->is_release()) ||
3232              (mb->trailing_load_store() && mem->is_LoadStore()), "missing mem op");
3233     } else if (mb->leading()) {
3234       assert(mb->trailing_membar()->leading_membar() == mb, "bad membar pair");
3235     }
3236   }
3237 #endif
3238   // Count FPU ops and common calls, implements item (3)
3239   bool gc_handled = BarrierSet::barrier_set()->barrier_set_c2()->final_graph_reshaping(this, n, nop, dead_nodes);
3240   if (!gc_handled) {
3241     final_graph_reshaping_main_switch(n, frc, nop, dead_nodes);
3242   }
3243 
3244   // Collect CFG split points
3245   if (n->is_MultiBranch() && !n->is_RangeCheck()) {
3246     frc._tests.push(n);
3247   }
3248 }
3249 
3250 void Compile::handle_div_mod_op(Node* n, BasicType bt, bool is_unsigned) {
3251   if (!UseDivMod) {
3252     return;
3253   }
3254 
3255   // Check if "a % b" and "a / b" both exist
3256   Node* d = n->find_similar(Op_DivIL(bt, is_unsigned));
3257   if (d == nullptr) {
3258     return;
3259   }
3260 
3261   // Replace them with a fused divmod if supported
3262   if (Matcher::has_match_rule(Op_DivModIL(bt, is_unsigned))) {
3263     DivModNode* divmod = DivModNode::make(n, bt, is_unsigned);
3264     // If the divisor input for a Div (or Mod etc.) is not zero, then the control input of the Div is set to zero.
3265     // It could be that the divisor input is found not zero because its type is narrowed down by a CastII in the
3266     // subgraph for that input. Range check CastIIs are removed during final graph reshape. To preserve the dependency
3267     // carried by a CastII, precedence edges are added to the Div node. We need to transfer the precedence edges to the
3268     // DivMod node so the dependency is not lost.
3269     divmod->add_prec_from(n);
3270     divmod->add_prec_from(d);
3271     d->subsume_by(divmod->div_proj(), this);
3272     n->subsume_by(divmod->mod_proj(), this);
3273   } else {
3274     // Replace "a % b" with "a - ((a / b) * b)"
3275     Node* mult = MulNode::make(d, d->in(2), bt);
3276     Node* sub = SubNode::make(d->in(1), mult, bt);
3277     n->subsume_by(sub, this);
3278   }
3279 }
3280 
3281 void Compile::final_graph_reshaping_main_switch(Node* n, Final_Reshape_Counts& frc, uint nop, Unique_Node_List& dead_nodes) {
3282   switch( nop ) {
3283   // Count all float operations that may use FPU
3284   case Op_AddHF:
3285   case Op_MulHF:
3286   case Op_AddF:
3287   case Op_SubF:
3288   case Op_MulF:
3289   case Op_DivF:
3290   case Op_NegF:
3291   case Op_ModF:
3292   case Op_ConvI2F:
3293   case Op_ConF:
3294   case Op_CmpF:
3295   case Op_CmpF3:
3296   case Op_StoreF:
3297   case Op_LoadF:
3298   // case Op_ConvL2F: // longs are split into 32-bit halves
3299     frc.inc_float_count();
3300     break;
3301 
3302   case Op_ConvF2D:
3303   case Op_ConvD2F:
3304     frc.inc_float_count();
3305     frc.inc_double_count();
3306     break;
3307 
3308   // Count all double operations that may use FPU
3309   case Op_AddD:
3310   case Op_SubD:
3311   case Op_MulD:
3312   case Op_DivD:
3313   case Op_NegD:
3314   case Op_ModD:
3315   case Op_ConvI2D:
3316   case Op_ConvD2I:
3317   // case Op_ConvL2D: // handled by leaf call
3318   // case Op_ConvD2L: // handled by leaf call
3319   case Op_ConD:
3320   case Op_CmpD:
3321   case Op_CmpD3:
3322   case Op_StoreD:
3323   case Op_LoadD:
3324   case Op_LoadD_unaligned:
3325     frc.inc_double_count();
3326     break;
3327   case Op_Opaque1:              // Remove Opaque Nodes before matching
3328     n->subsume_by(n->in(1), this);
3329     break;
3330   case Op_CallLeafPure: {
3331     // If the pure call is not supported, then lower to a CallLeaf.
3332     if (!Matcher::match_rule_supported(Op_CallLeafPure)) {
3333       CallNode* call = n->as_Call();
3334       CallNode* new_call = new CallLeafNode(call->tf(), call->entry_point(),
3335                                             call->_name, TypeRawPtr::BOTTOM);
3336       new_call->init_req(TypeFunc::Control, call->in(TypeFunc::Control));
3337       new_call->init_req(TypeFunc::I_O, C->top());
3338       new_call->init_req(TypeFunc::Memory, C->top());
3339       new_call->init_req(TypeFunc::ReturnAdr, C->top());
3340       new_call->init_req(TypeFunc::FramePtr, C->top());
3341       for (unsigned int i = TypeFunc::Parms; i < call->tf()->domain()->cnt(); i++) {
3342         new_call->init_req(i, call->in(i));
3343       }
3344       n->subsume_by(new_call, this);
3345     }
3346     frc.inc_call_count();
3347     break;
3348   }
3349   case Op_CallStaticJava:
3350   case Op_CallJava:
3351   case Op_CallDynamicJava:
3352     frc.inc_java_call_count(); // Count java call site;
3353   case Op_CallRuntime:
3354   case Op_CallLeaf:
3355   case Op_CallLeafVector:
3356   case Op_CallLeafNoFP: {
3357     assert (n->is_Call(), "");
3358     CallNode *call = n->as_Call();
3359     // Count call sites where the FP mode bit would have to be flipped.
3360     // Do not count uncommon runtime calls:
3361     // uncommon_trap, _complete_monitor_locking, _complete_monitor_unlocking,
3362     // _new_Java, _new_typeArray, _new_objArray, _rethrow_Java, ...
3363     if (!call->is_CallStaticJava() || !call->as_CallStaticJava()->_name) {
3364       frc.inc_call_count();   // Count the call site
3365     } else {                  // See if uncommon argument is shared
3366       Node *n = call->in(TypeFunc::Parms);
3367       int nop = n->Opcode();
3368       // Clone shared simple arguments to uncommon calls, item (1).
3369       if (n->outcnt() > 1 &&
3370           !n->is_Proj() &&
3371           nop != Op_CreateEx &&
3372           nop != Op_CheckCastPP &&
3373           nop != Op_DecodeN &&
3374           nop != Op_DecodeNKlass &&
3375           !n->is_Mem() &&
3376           !n->is_Phi()) {
3377         Node *x = n->clone();
3378         call->set_req(TypeFunc::Parms, x);
3379       }
3380     }
3381     break;
3382   }
3383   case Op_StoreB:
3384   case Op_StoreC:
3385   case Op_StoreI:
3386   case Op_StoreL:
3387   case Op_CompareAndSwapB:
3388   case Op_CompareAndSwapS:
3389   case Op_CompareAndSwapI:
3390   case Op_CompareAndSwapL:
3391   case Op_CompareAndSwapP:
3392   case Op_CompareAndSwapN:
3393   case Op_WeakCompareAndSwapB:
3394   case Op_WeakCompareAndSwapS:
3395   case Op_WeakCompareAndSwapI:
3396   case Op_WeakCompareAndSwapL:
3397   case Op_WeakCompareAndSwapP:
3398   case Op_WeakCompareAndSwapN:
3399   case Op_CompareAndExchangeB:
3400   case Op_CompareAndExchangeS:
3401   case Op_CompareAndExchangeI:
3402   case Op_CompareAndExchangeL:
3403   case Op_CompareAndExchangeP:
3404   case Op_CompareAndExchangeN:
3405   case Op_GetAndAddS:
3406   case Op_GetAndAddB:
3407   case Op_GetAndAddI:
3408   case Op_GetAndAddL:
3409   case Op_GetAndSetS:
3410   case Op_GetAndSetB:
3411   case Op_GetAndSetI:
3412   case Op_GetAndSetL:
3413   case Op_GetAndSetP:
3414   case Op_GetAndSetN:
3415   case Op_StoreP:
3416   case Op_StoreN:
3417   case Op_StoreNKlass:
3418   case Op_LoadB:
3419   case Op_LoadUB:
3420   case Op_LoadUS:
3421   case Op_LoadI:
3422   case Op_LoadKlass:
3423   case Op_LoadNKlass:
3424   case Op_LoadL:
3425   case Op_LoadL_unaligned:
3426   case Op_LoadP:
3427   case Op_LoadN:
3428   case Op_LoadRange:
3429   case Op_LoadS:
3430     break;
3431 
3432   case Op_AddP: {               // Assert sane base pointers
3433     Node *addp = n->in(AddPNode::Address);
3434     assert(n->as_AddP()->address_input_has_same_base(), "Base pointers must match (addp %u)", addp->_idx );
3435 #ifdef _LP64
3436     if (addp->Opcode() == Op_ConP &&
3437         addp == n->in(AddPNode::Base) &&
3438         n->in(AddPNode::Offset)->is_Con()) {
3439       // If the transformation of ConP to ConN+DecodeN is beneficial depends
3440       // on the platform and on the compressed oops mode.
3441       // Use addressing with narrow klass to load with offset on x86.
3442       // Some platforms can use the constant pool to load ConP.
3443       // Do this transformation here since IGVN will convert ConN back to ConP.
3444       const Type* t = addp->bottom_type();
3445       bool is_oop   = t->isa_oopptr() != nullptr;
3446       bool is_klass = t->isa_klassptr() != nullptr;
3447 
3448       if ((is_oop   && UseCompressedOops          && Matcher::const_oop_prefer_decode()  ) ||
3449           (is_klass && Matcher::const_klass_prefer_decode() &&
3450            t->isa_klassptr()->exact_klass()->is_in_encoding_range())) {
3451         Node* nn = nullptr;
3452 
3453         int op = is_oop ? Op_ConN : Op_ConNKlass;
3454 
3455         // Look for existing ConN node of the same exact type.
3456         Node* r  = root();
3457         uint cnt = r->outcnt();
3458         for (uint i = 0; i < cnt; i++) {
3459           Node* m = r->raw_out(i);
3460           if (m!= nullptr && m->Opcode() == op &&
3461               m->bottom_type()->make_ptr() == t) {
3462             nn = m;
3463             break;
3464           }
3465         }
3466         if (nn != nullptr) {
3467           // Decode a narrow oop to match address
3468           // [R12 + narrow_oop_reg<<3 + offset]
3469           if (is_oop) {
3470             nn = new DecodeNNode(nn, t);
3471           } else {
3472             nn = new DecodeNKlassNode(nn, t);
3473           }
3474           // Check for succeeding AddP which uses the same Base.
3475           // Otherwise we will run into the assertion above when visiting that guy.
3476           for (uint i = 0; i < n->outcnt(); ++i) {
3477             Node *out_i = n->raw_out(i);
3478             if (out_i && out_i->is_AddP() && out_i->in(AddPNode::Base) == addp) {
3479               out_i->set_req(AddPNode::Base, nn);
3480 #ifdef ASSERT
3481               for (uint j = 0; j < out_i->outcnt(); ++j) {
3482                 Node *out_j = out_i->raw_out(j);
3483                 assert(out_j == nullptr || !out_j->is_AddP() || out_j->in(AddPNode::Base) != addp,
3484                        "more than 2 AddP nodes in a chain (out_j %u)", out_j->_idx);
3485               }
3486 #endif
3487             }
3488           }
3489           n->set_req(AddPNode::Base, nn);
3490           n->set_req(AddPNode::Address, nn);
3491           if (addp->outcnt() == 0) {
3492             addp->disconnect_inputs(this);
3493           }
3494         }
3495       }
3496     }
3497 #endif
3498     break;
3499   }
3500 
3501   case Op_CastPP: {
3502     // Remove CastPP nodes to gain more freedom during scheduling but
3503     // keep the dependency they encode as control or precedence edges
3504     // (if control is set already) on memory operations. Some CastPP
3505     // nodes don't have a control (don't carry a dependency): skip
3506     // those.
3507     if (n->in(0) != nullptr) {
3508       ResourceMark rm;
3509       Unique_Node_List wq;
3510       wq.push(n);
3511       for (uint next = 0; next < wq.size(); ++next) {
3512         Node *m = wq.at(next);
3513         for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
3514           Node* use = m->fast_out(i);
3515           if (use->is_Mem() || use->is_EncodeNarrowPtr()) {
3516             use->ensure_control_or_add_prec(n->in(0));
3517           } else {
3518             switch(use->Opcode()) {
3519             case Op_AddP:
3520             case Op_DecodeN:
3521             case Op_DecodeNKlass:
3522             case Op_CheckCastPP:
3523             case Op_CastPP:
3524               wq.push(use);
3525               break;
3526             }
3527           }
3528         }
3529       }
3530     }
3531     const bool is_LP64 = LP64_ONLY(true) NOT_LP64(false);
3532     if (is_LP64 && n->in(1)->is_DecodeN() && Matcher::gen_narrow_oop_implicit_null_checks()) {
3533       Node* in1 = n->in(1);
3534       const Type* t = n->bottom_type();
3535       Node* new_in1 = in1->clone();
3536       new_in1->as_DecodeN()->set_type(t);
3537 
3538       if (!Matcher::narrow_oop_use_complex_address()) {
3539         //
3540         // x86, ARM and friends can handle 2 adds in addressing mode
3541         // and Matcher can fold a DecodeN node into address by using
3542         // a narrow oop directly and do implicit null check in address:
3543         //
3544         // [R12 + narrow_oop_reg<<3 + offset]
3545         // NullCheck narrow_oop_reg
3546         //
3547         // On other platforms (Sparc) we have to keep new DecodeN node and
3548         // use it to do implicit null check in address:
3549         //
3550         // decode_not_null narrow_oop_reg, base_reg
3551         // [base_reg + offset]
3552         // NullCheck base_reg
3553         //
3554         // Pin the new DecodeN node to non-null path on these platform (Sparc)
3555         // to keep the information to which null check the new DecodeN node
3556         // corresponds to use it as value in implicit_null_check().
3557         //
3558         new_in1->set_req(0, n->in(0));
3559       }
3560 
3561       n->subsume_by(new_in1, this);
3562       if (in1->outcnt() == 0) {
3563         in1->disconnect_inputs(this);
3564       }
3565     } else {
3566       n->subsume_by(n->in(1), this);
3567       if (n->outcnt() == 0) {
3568         n->disconnect_inputs(this);
3569       }
3570     }
3571     break;
3572   }
3573   case Op_CastII: {
3574     n->as_CastII()->remove_range_check_cast(this);
3575     break;
3576   }
3577 #ifdef _LP64
3578   case Op_CmpP:
3579     // Do this transformation here to preserve CmpPNode::sub() and
3580     // other TypePtr related Ideal optimizations (for example, ptr nullness).
3581     if (n->in(1)->is_DecodeNarrowPtr() || n->in(2)->is_DecodeNarrowPtr()) {
3582       Node* in1 = n->in(1);
3583       Node* in2 = n->in(2);
3584       if (!in1->is_DecodeNarrowPtr()) {
3585         in2 = in1;
3586         in1 = n->in(2);
3587       }
3588       assert(in1->is_DecodeNarrowPtr(), "sanity");
3589 
3590       Node* new_in2 = nullptr;
3591       if (in2->is_DecodeNarrowPtr()) {
3592         assert(in2->Opcode() == in1->Opcode(), "must be same node type");
3593         new_in2 = in2->in(1);
3594       } else if (in2->Opcode() == Op_ConP) {
3595         const Type* t = in2->bottom_type();
3596         if (t == TypePtr::NULL_PTR) {
3597           assert(in1->is_DecodeN(), "compare klass to null?");
3598           // Don't convert CmpP null check into CmpN if compressed
3599           // oops implicit null check is not generated.
3600           // This will allow to generate normal oop implicit null check.
3601           if (Matcher::gen_narrow_oop_implicit_null_checks())
3602             new_in2 = ConNode::make(TypeNarrowOop::NULL_PTR);
3603           //
3604           // This transformation together with CastPP transformation above
3605           // will generated code for implicit null checks for compressed oops.
3606           //
3607           // The original code after Optimize()
3608           //
3609           //    LoadN memory, narrow_oop_reg
3610           //    decode narrow_oop_reg, base_reg
3611           //    CmpP base_reg, nullptr
3612           //    CastPP base_reg // NotNull
3613           //    Load [base_reg + offset], val_reg
3614           //
3615           // after these transformations will be
3616           //
3617           //    LoadN memory, narrow_oop_reg
3618           //    CmpN narrow_oop_reg, nullptr
3619           //    decode_not_null narrow_oop_reg, base_reg
3620           //    Load [base_reg + offset], val_reg
3621           //
3622           // and the uncommon path (== nullptr) will use narrow_oop_reg directly
3623           // since narrow oops can be used in debug info now (see the code in
3624           // final_graph_reshaping_walk()).
3625           //
3626           // At the end the code will be matched to
3627           // on x86:
3628           //
3629           //    Load_narrow_oop memory, narrow_oop_reg
3630           //    Load [R12 + narrow_oop_reg<<3 + offset], val_reg
3631           //    NullCheck narrow_oop_reg
3632           //
3633           // and on sparc:
3634           //
3635           //    Load_narrow_oop memory, narrow_oop_reg
3636           //    decode_not_null narrow_oop_reg, base_reg
3637           //    Load [base_reg + offset], val_reg
3638           //    NullCheck base_reg
3639           //
3640         } else if (t->isa_oopptr()) {
3641           new_in2 = ConNode::make(t->make_narrowoop());
3642         } else if (t->isa_klassptr()) {
3643           ciKlass* klass = t->is_klassptr()->exact_klass();
3644           if (klass->is_in_encoding_range()) {
3645             new_in2 = ConNode::make(t->make_narrowklass());
3646           }
3647         }
3648       }
3649       if (new_in2 != nullptr) {
3650         Node* cmpN = new CmpNNode(in1->in(1), new_in2);
3651         n->subsume_by(cmpN, this);
3652         if (in1->outcnt() == 0) {
3653           in1->disconnect_inputs(this);
3654         }
3655         if (in2->outcnt() == 0) {
3656           in2->disconnect_inputs(this);
3657         }
3658       }
3659     }
3660     break;
3661 
3662   case Op_DecodeN:
3663   case Op_DecodeNKlass:
3664     assert(!n->in(1)->is_EncodeNarrowPtr(), "should be optimized out");
3665     // DecodeN could be pinned when it can't be fold into
3666     // an address expression, see the code for Op_CastPP above.
3667     assert(n->in(0) == nullptr || (UseCompressedOops && !Matcher::narrow_oop_use_complex_address()), "no control");
3668     break;
3669 
3670   case Op_EncodeP:
3671   case Op_EncodePKlass: {
3672     Node* in1 = n->in(1);
3673     if (in1->is_DecodeNarrowPtr()) {
3674       n->subsume_by(in1->in(1), this);
3675     } else if (in1->Opcode() == Op_ConP) {
3676       const Type* t = in1->bottom_type();
3677       if (t == TypePtr::NULL_PTR) {
3678         assert(t->isa_oopptr(), "null klass?");
3679         n->subsume_by(ConNode::make(TypeNarrowOop::NULL_PTR), this);
3680       } else if (t->isa_oopptr()) {
3681         n->subsume_by(ConNode::make(t->make_narrowoop()), this);
3682       } else if (t->isa_klassptr()) {
3683         ciKlass* klass = t->is_klassptr()->exact_klass();
3684         if (klass->is_in_encoding_range()) {
3685           n->subsume_by(ConNode::make(t->make_narrowklass()), this);
3686         } else {
3687           assert(false, "unencodable klass in ConP -> EncodeP");
3688           C->record_failure("unencodable klass in ConP -> EncodeP");
3689         }
3690       }
3691     }
3692     if (in1->outcnt() == 0) {
3693       in1->disconnect_inputs(this);
3694     }
3695     break;
3696   }
3697 
3698   case Op_Proj: {
3699     if (OptimizeStringConcat || IncrementalInline) {
3700       ProjNode* proj = n->as_Proj();
3701       if (proj->_is_io_use) {
3702         assert(proj->_con == TypeFunc::I_O || proj->_con == TypeFunc::Memory, "");
3703         // Separate projections were used for the exception path which
3704         // are normally removed by a late inline.  If it wasn't inlined
3705         // then they will hang around and should just be replaced with
3706         // the original one. Merge them.
3707         Node* non_io_proj = proj->in(0)->as_Multi()->proj_out_or_null(proj->_con, false /*is_io_use*/);
3708         if (non_io_proj  != nullptr) {
3709           proj->subsume_by(non_io_proj , this);
3710         }
3711       }
3712     }
3713     break;
3714   }
3715 
3716   case Op_Phi:
3717     if (n->as_Phi()->bottom_type()->isa_narrowoop() || n->as_Phi()->bottom_type()->isa_narrowklass()) {
3718       // The EncodeP optimization may create Phi with the same edges
3719       // for all paths. It is not handled well by Register Allocator.
3720       Node* unique_in = n->in(1);
3721       assert(unique_in != nullptr, "");
3722       uint cnt = n->req();
3723       for (uint i = 2; i < cnt; i++) {
3724         Node* m = n->in(i);
3725         assert(m != nullptr, "");
3726         if (unique_in != m)
3727           unique_in = nullptr;
3728       }
3729       if (unique_in != nullptr) {
3730         n->subsume_by(unique_in, this);
3731       }
3732     }
3733     break;
3734 
3735 #endif
3736 
3737   case Op_ModI:
3738     handle_div_mod_op(n, T_INT, false);
3739     break;
3740 
3741   case Op_ModL:
3742     handle_div_mod_op(n, T_LONG, false);
3743     break;
3744 
3745   case Op_UModI:
3746     handle_div_mod_op(n, T_INT, true);
3747     break;
3748 
3749   case Op_UModL:
3750     handle_div_mod_op(n, T_LONG, true);
3751     break;
3752 
3753   case Op_LoadVector:
3754   case Op_StoreVector:
3755 #ifdef ASSERT
3756     // Add VerifyVectorAlignment node between adr and load / store.
3757     if (VerifyAlignVector && Matcher::has_match_rule(Op_VerifyVectorAlignment)) {
3758       bool must_verify_alignment = n->is_LoadVector() ? n->as_LoadVector()->must_verify_alignment() :
3759                                                         n->as_StoreVector()->must_verify_alignment();
3760       if (must_verify_alignment) {
3761         jlong vector_width = n->is_LoadVector() ? n->as_LoadVector()->memory_size() :
3762                                                   n->as_StoreVector()->memory_size();
3763         // The memory access should be aligned to the vector width in bytes.
3764         // However, the underlying array is possibly less well aligned, but at least
3765         // to ObjectAlignmentInBytes. Hence, even if multiple arrays are accessed in
3766         // a loop we can expect at least the following alignment:
3767         jlong guaranteed_alignment = MIN2(vector_width, (jlong)ObjectAlignmentInBytes);
3768         assert(2 <= guaranteed_alignment && guaranteed_alignment <= 64, "alignment must be in range");
3769         assert(is_power_of_2(guaranteed_alignment), "alignment must be power of 2");
3770         // Create mask from alignment. e.g. 0b1000 -> 0b0111
3771         jlong mask = guaranteed_alignment - 1;
3772         Node* mask_con = ConLNode::make(mask);
3773         VerifyVectorAlignmentNode* va = new VerifyVectorAlignmentNode(n->in(MemNode::Address), mask_con);
3774         n->set_req(MemNode::Address, va);
3775       }
3776     }
3777 #endif
3778     break;
3779 
3780   case Op_LoadVectorGather:
3781   case Op_StoreVectorScatter:
3782   case Op_LoadVectorGatherMasked:
3783   case Op_StoreVectorScatterMasked:
3784   case Op_VectorCmpMasked:
3785   case Op_VectorMaskGen:
3786   case Op_LoadVectorMasked:
3787   case Op_StoreVectorMasked:
3788     break;
3789 
3790   case Op_AddReductionVI:
3791   case Op_AddReductionVL:
3792   case Op_AddReductionVHF:
3793   case Op_AddReductionVF:
3794   case Op_AddReductionVD:
3795   case Op_MulReductionVI:
3796   case Op_MulReductionVL:
3797   case Op_MulReductionVHF:
3798   case Op_MulReductionVF:
3799   case Op_MulReductionVD:
3800   case Op_MinReductionV:
3801   case Op_MaxReductionV:
3802   case Op_UMinReductionV:
3803   case Op_UMaxReductionV:
3804   case Op_AndReductionV:
3805   case Op_OrReductionV:
3806   case Op_XorReductionV:
3807     break;
3808 
3809   case Op_PackB:
3810   case Op_PackS:
3811   case Op_PackI:
3812   case Op_PackF:
3813   case Op_PackL:
3814   case Op_PackD:
3815     if (n->req()-1 > 2) {
3816       // Replace many operand PackNodes with a binary tree for matching
3817       PackNode* p = (PackNode*) n;
3818       Node* btp = p->binary_tree_pack(1, n->req());
3819       n->subsume_by(btp, this);
3820     }
3821     break;
3822   case Op_Loop:
3823     // When StressCountedLoop is enabled, this loop may intentionally avoid a counted loop conversion.
3824     // This is expected behavior for the stress mode, which exercises alternative compilation paths.
3825     if (!StressCountedLoop) {
3826       assert(!n->as_Loop()->is_loop_nest_inner_loop() || _loop_opts_cnt == 0, "should have been turned into a counted loop");
3827     }
3828   case Op_CountedLoop:
3829   case Op_LongCountedLoop:
3830   case Op_OuterStripMinedLoop:
3831     if (n->as_Loop()->is_inner_loop()) {
3832       frc.inc_inner_loop_count();
3833     }
3834     n->as_Loop()->verify_strip_mined(0);
3835     break;
3836   case Op_LShiftI:
3837   case Op_RShiftI:
3838   case Op_URShiftI:
3839   case Op_LShiftL:
3840   case Op_RShiftL:
3841   case Op_URShiftL:
3842     if (Matcher::need_masked_shift_count) {
3843       // The cpu's shift instructions don't restrict the count to the
3844       // lower 5/6 bits. We need to do the masking ourselves.
3845       Node* in2 = n->in(2);
3846       juint mask = (n->bottom_type() == TypeInt::INT) ? (BitsPerInt - 1) : (BitsPerLong - 1);
3847       const TypeInt* t = in2->find_int_type();
3848       if (t != nullptr && t->is_con()) {
3849         juint shift = t->get_con();
3850         if (shift > mask) { // Unsigned cmp
3851           n->set_req(2, ConNode::make(TypeInt::make(shift & mask)));
3852         }
3853       } else {
3854         if (t == nullptr || t->_lo < 0 || t->_hi > (int)mask) {
3855           Node* shift = new AndINode(in2, ConNode::make(TypeInt::make(mask)));
3856           n->set_req(2, shift);
3857         }
3858       }
3859       if (in2->outcnt() == 0) { // Remove dead node
3860         in2->disconnect_inputs(this);
3861       }
3862     }
3863     break;
3864   case Op_MemBarStoreStore:
3865   case Op_MemBarRelease:
3866     // Break the link with AllocateNode: it is no longer useful and
3867     // confuses register allocation.
3868     if (n->req() > MemBarNode::Precedent) {
3869       n->set_req(MemBarNode::Precedent, top());
3870     }
3871     break;
3872   case Op_MemBarAcquire: {
3873     if (n->as_MemBar()->trailing_load() && n->req() > MemBarNode::Precedent) {
3874       // At parse time, the trailing MemBarAcquire for a volatile load
3875       // is created with an edge to the load. After optimizations,
3876       // that input may be a chain of Phis. If those phis have no
3877       // other use, then the MemBarAcquire keeps them alive and
3878       // register allocation can be confused.
3879       dead_nodes.push(n->in(MemBarNode::Precedent));
3880       n->set_req(MemBarNode::Precedent, top());
3881     }
3882     break;
3883   }
3884   case Op_Blackhole:
3885     break;
3886   case Op_RangeCheck: {
3887     RangeCheckNode* rc = n->as_RangeCheck();
3888     Node* iff = new IfNode(rc->in(0), rc->in(1), rc->_prob, rc->_fcnt);
3889     n->subsume_by(iff, this);
3890     frc._tests.push(iff);
3891     break;
3892   }
3893   case Op_ConvI2L: {
3894     if (!Matcher::convi2l_type_required) {
3895       // Code generation on some platforms doesn't need accurate
3896       // ConvI2L types. Widening the type can help remove redundant
3897       // address computations.
3898       n->as_Type()->set_type(TypeLong::INT);
3899       ResourceMark rm;
3900       Unique_Node_List wq;
3901       wq.push(n);
3902       for (uint next = 0; next < wq.size(); next++) {
3903         Node *m = wq.at(next);
3904 
3905         for(;;) {
3906           // Loop over all nodes with identical inputs edges as m
3907           Node* k = m->find_similar(m->Opcode());
3908           if (k == nullptr) {
3909             break;
3910           }
3911           // Push their uses so we get a chance to remove node made
3912           // redundant
3913           for (DUIterator_Fast imax, i = k->fast_outs(imax); i < imax; i++) {
3914             Node* u = k->fast_out(i);
3915             if (u->Opcode() == Op_LShiftL ||
3916                 u->Opcode() == Op_AddL ||
3917                 u->Opcode() == Op_SubL ||
3918                 u->Opcode() == Op_AddP) {
3919               wq.push(u);
3920             }
3921           }
3922           // Replace all nodes with identical edges as m with m
3923           k->subsume_by(m, this);
3924         }
3925       }
3926     }
3927     break;
3928   }
3929   case Op_CmpUL: {
3930     if (!Matcher::has_match_rule(Op_CmpUL)) {
3931       // No support for unsigned long comparisons
3932       ConINode* sign_pos = new ConINode(TypeInt::make(BitsPerLong - 1));
3933       Node* sign_bit_mask = new RShiftLNode(n->in(1), sign_pos);
3934       Node* orl = new OrLNode(n->in(1), sign_bit_mask);
3935       ConLNode* remove_sign_mask = new ConLNode(TypeLong::make(max_jlong));
3936       Node* andl = new AndLNode(orl, remove_sign_mask);
3937       Node* cmp = new CmpLNode(andl, n->in(2));
3938       n->subsume_by(cmp, this);
3939     }
3940     break;
3941   }
3942 #ifdef ASSERT
3943   case Op_ConNKlass: {
3944     const TypePtr* tp = n->as_Type()->type()->make_ptr();
3945     ciKlass* klass = tp->is_klassptr()->exact_klass();
3946     assert(klass->is_in_encoding_range(), "klass cannot be compressed");
3947     break;
3948   }
3949 #endif
3950   default:
3951     assert(!n->is_Call(), "");
3952     assert(!n->is_Mem(), "");
3953     assert(nop != Op_ProfileBoolean, "should be eliminated during IGVN");
3954     break;
3955   }
3956 }
3957 
3958 //------------------------------final_graph_reshaping_walk---------------------
3959 // Replacing Opaque nodes with their input in final_graph_reshaping_impl(),
3960 // requires that the walk visits a node's inputs before visiting the node.
3961 void Compile::final_graph_reshaping_walk(Node_Stack& nstack, Node* root, Final_Reshape_Counts& frc, Unique_Node_List& dead_nodes) {
3962   Unique_Node_List sfpt;
3963 
3964   frc._visited.set(root->_idx); // first, mark node as visited
3965   uint cnt = root->req();
3966   Node *n = root;
3967   uint  i = 0;
3968   while (true) {
3969     if (i < cnt) {
3970       // Place all non-visited non-null inputs onto stack
3971       Node* m = n->in(i);
3972       ++i;
3973       if (m != nullptr && !frc._visited.test_set(m->_idx)) {
3974         if (m->is_SafePoint() && m->as_SafePoint()->jvms() != nullptr) {
3975           // compute worst case interpreter size in case of a deoptimization
3976           update_interpreter_frame_size(m->as_SafePoint()->jvms()->interpreter_frame_size());
3977 
3978           sfpt.push(m);
3979         }
3980         cnt = m->req();
3981         nstack.push(n, i); // put on stack parent and next input's index
3982         n = m;
3983         i = 0;
3984       }
3985     } else {
3986       // Now do post-visit work
3987       final_graph_reshaping_impl(n, frc, dead_nodes);
3988       if (nstack.is_empty())
3989         break;             // finished
3990       n = nstack.node();   // Get node from stack
3991       cnt = n->req();
3992       i = nstack.index();
3993       nstack.pop();        // Shift to the next node on stack
3994     }
3995   }
3996 
3997   expand_reachability_edges(sfpt);
3998 
3999   // Skip next transformation if compressed oops are not used.
4000   if (UseCompressedOops && !Matcher::gen_narrow_oop_implicit_null_checks())
4001     return;
4002 
4003   // Go over ReachabilityFence nodes to skip DecodeN nodes for referents.
4004   // The sole purpose of RF node is to keep the referent oop alive and
4005   // decoding the oop for that is not needed.
4006   for (int i = 0; i < C->reachability_fences_count(); i++) {
4007     ReachabilityFenceNode* rf = C->reachability_fence(i);
4008     DecodeNNode* dn = rf->in(1)->isa_DecodeN();
4009     if (dn != nullptr) {
4010       if (!dn->has_non_debug_uses() || Matcher::narrow_oop_use_complex_address()) {
4011         rf->set_req(1, dn->in(1));
4012         if (dn->outcnt() == 0) {
4013           dn->disconnect_inputs(this);
4014         }
4015       }
4016     }
4017   }
4018 
4019   // Go over safepoints nodes to skip DecodeN/DecodeNKlass nodes for debug edges.
4020   // It could be done for an uncommon traps or any safepoints/calls
4021   // if the DecodeN/DecodeNKlass node is referenced only in a debug info.
4022   while (sfpt.size() > 0) {
4023     n = sfpt.pop();
4024     JVMState *jvms = n->as_SafePoint()->jvms();
4025     assert(jvms != nullptr, "sanity");
4026     int start = jvms->debug_start();
4027     int end   = n->req();
4028     bool is_uncommon = (n->is_CallStaticJava() &&
4029                         n->as_CallStaticJava()->uncommon_trap_request() != 0);
4030     for (int j = start; j < end; j++) {
4031       Node* in = n->in(j);
4032       if (in->is_DecodeNarrowPtr() && (is_uncommon || !in->has_non_debug_uses())) {
4033         n->set_req(j, in->in(1));
4034         if (in->outcnt() == 0) {
4035           in->disconnect_inputs(this);
4036         }
4037       }
4038     }
4039   }
4040 }
4041 
4042 //------------------------------final_graph_reshaping--------------------------
4043 // Final Graph Reshaping.
4044 //
4045 // (1) Clone simple inputs to uncommon calls, so they can be scheduled late
4046 //     and not commoned up and forced early.  Must come after regular
4047 //     optimizations to avoid GVN undoing the cloning.  Clone constant
4048 //     inputs to Loop Phis; these will be split by the allocator anyways.
4049 //     Remove Opaque nodes.
4050 // (2) Move last-uses by commutative operations to the left input to encourage
4051 //     Intel update-in-place two-address operations and better register usage
4052 //     on RISCs.  Must come after regular optimizations to avoid GVN Ideal
4053 //     calls canonicalizing them back.
4054 // (3) Count the number of double-precision FP ops, single-precision FP ops
4055 //     and call sites.  On Intel, we can get correct rounding either by
4056 //     forcing singles to memory (requires extra stores and loads after each
4057 //     FP bytecode) or we can set a rounding mode bit (requires setting and
4058 //     clearing the mode bit around call sites).  The mode bit is only used
4059 //     if the relative frequency of single FP ops to calls is low enough.
4060 //     This is a key transform for SPEC mpeg_audio.
4061 // (4) Detect infinite loops; blobs of code reachable from above but not
4062 //     below.  Several of the Code_Gen algorithms fail on such code shapes,
4063 //     so we simply bail out.  Happens a lot in ZKM.jar, but also happens
4064 //     from time to time in other codes (such as -Xcomp finalizer loops, etc).
4065 //     Detection is by looking for IfNodes where only 1 projection is
4066 //     reachable from below or CatchNodes missing some targets.
4067 // (5) Assert for insane oop offsets in debug mode.
4068 
4069 bool Compile::final_graph_reshaping() {
4070   // an infinite loop may have been eliminated by the optimizer,
4071   // in which case the graph will be empty.
4072   if (root()->req() == 1) {
4073     // Do not compile method that is only a trivial infinite loop,
4074     // since the content of the loop may have been eliminated.
4075     record_method_not_compilable("trivial infinite loop");
4076     return true;
4077   }
4078 
4079   // Expensive nodes have their control input set to prevent the GVN
4080   // from freely commoning them. There's no GVN beyond this point so
4081   // no need to keep the control input. We want the expensive nodes to
4082   // be freely moved to the least frequent code path by gcm.
4083   assert(OptimizeExpensiveOps || expensive_count() == 0, "optimization off but list non empty?");
4084   for (int i = 0; i < expensive_count(); i++) {
4085     _expensive_nodes.at(i)->set_req(0, nullptr);
4086   }
4087 
4088   Final_Reshape_Counts frc;
4089 
4090   // Visit everybody reachable!
4091   // Allocate stack of size C->live_nodes()/2 to avoid frequent realloc
4092   Node_Stack nstack(live_nodes() >> 1);
4093   Unique_Node_List dead_nodes;
4094   final_graph_reshaping_walk(nstack, root(), frc, dead_nodes);
4095 
4096   // Check for unreachable (from below) code (i.e., infinite loops).
4097   for( uint i = 0; i < frc._tests.size(); i++ ) {
4098     MultiBranchNode *n = frc._tests[i]->as_MultiBranch();
4099     // Get number of CFG targets.
4100     // Note that PCTables include exception targets after calls.
4101     uint required_outcnt = n->required_outcnt();
4102     if (n->outcnt() != required_outcnt) {
4103       // Check for a few special cases.  Rethrow Nodes never take the
4104       // 'fall-thru' path, so expected kids is 1 less.
4105       if (n->is_PCTable() && n->in(0) && n->in(0)->in(0)) {
4106         if (n->in(0)->in(0)->is_Call()) {
4107           CallNode* call = n->in(0)->in(0)->as_Call();
4108           if (call->entry_point() == OptoRuntime::rethrow_stub()) {
4109             required_outcnt--;      // Rethrow always has 1 less kid
4110           } else if (call->req() > TypeFunc::Parms &&
4111                      call->is_CallDynamicJava()) {
4112             // Check for null receiver. In such case, the optimizer has
4113             // detected that the virtual call will always result in a null
4114             // pointer exception. The fall-through projection of this CatchNode
4115             // will not be populated.
4116             Node* arg0 = call->in(TypeFunc::Parms);
4117             if (arg0->is_Type() &&
4118                 arg0->as_Type()->type()->higher_equal(TypePtr::NULL_PTR)) {
4119               required_outcnt--;
4120             }
4121           } else if (call->entry_point() == OptoRuntime::new_array_Java() ||
4122                      call->entry_point() == OptoRuntime::new_array_nozero_Java()) {
4123             // Check for illegal array length. In such case, the optimizer has
4124             // detected that the allocation attempt will always result in an
4125             // exception. There is no fall-through projection of this CatchNode .
4126             assert(call->is_CallStaticJava(), "static call expected");
4127             assert(call->req() == call->jvms()->endoff() + 1, "missing extra input");
4128             uint valid_length_test_input = call->req() - 1;
4129             Node* valid_length_test = call->in(valid_length_test_input);
4130             call->del_req(valid_length_test_input);
4131             if (valid_length_test->find_int_con(1) == 0) {
4132               required_outcnt--;
4133             }
4134             dead_nodes.push(valid_length_test);
4135             assert(n->outcnt() == required_outcnt, "malformed control flow");
4136             continue;
4137           }
4138         }
4139       }
4140 
4141       // Recheck with a better notion of 'required_outcnt'
4142       if (n->outcnt() != required_outcnt) {
4143         record_method_not_compilable("malformed control flow");
4144         return true;            // Not all targets reachable!
4145       }
4146     } else if (n->is_PCTable() && n->in(0) && n->in(0)->in(0) && n->in(0)->in(0)->is_Call()) {
4147       CallNode* call = n->in(0)->in(0)->as_Call();
4148       if (call->entry_point() == OptoRuntime::new_array_Java() ||
4149           call->entry_point() == OptoRuntime::new_array_nozero_Java()) {
4150         assert(call->is_CallStaticJava(), "static call expected");
4151         assert(call->req() == call->jvms()->endoff() + 1, "missing extra input");
4152         uint valid_length_test_input = call->req() - 1;
4153         dead_nodes.push(call->in(valid_length_test_input));
4154         call->del_req(valid_length_test_input); // valid length test useless now
4155       }
4156     }
4157     // Check that I actually visited all kids.  Unreached kids
4158     // must be infinite loops.
4159     for (DUIterator_Fast jmax, j = n->fast_outs(jmax); j < jmax; j++)
4160       if (!frc._visited.test(n->fast_out(j)->_idx)) {
4161         record_method_not_compilable("infinite loop");
4162         return true;            // Found unvisited kid; must be unreach
4163       }
4164 
4165     // Here so verification code in final_graph_reshaping_walk()
4166     // always see an OuterStripMinedLoopEnd
4167     if (n->is_OuterStripMinedLoopEnd() || n->is_LongCountedLoopEnd()) {
4168       IfNode* init_iff = n->as_If();
4169       Node* iff = new IfNode(init_iff->in(0), init_iff->in(1), init_iff->_prob, init_iff->_fcnt);
4170       n->subsume_by(iff, this);
4171     }
4172   }
4173 
4174   while (dead_nodes.size() > 0) {
4175     Node* m = dead_nodes.pop();
4176     if (m->outcnt() == 0 && m != top()) {
4177       for (uint j = 0; j < m->req(); j++) {
4178         Node* in = m->in(j);
4179         if (in != nullptr) {
4180           dead_nodes.push(in);
4181         }
4182       }
4183       m->disconnect_inputs(this);
4184     }
4185   }
4186 
4187   set_java_calls(frc.get_java_call_count());
4188   set_inner_loops(frc.get_inner_loop_count());
4189 
4190   // No infinite loops, no reason to bail out.
4191   return false;
4192 }
4193 
4194 //-----------------------------too_many_traps----------------------------------
4195 // Report if there are too many traps at the current method and bci.
4196 // Return true if there was a trap, and/or PerMethodTrapLimit is exceeded.
4197 bool Compile::too_many_traps(ciMethod* method,
4198                              int bci,
4199                              Deoptimization::DeoptReason reason) {
4200   ciMethodData* md = method->method_data();
4201   if (md->is_empty()) {
4202     // Assume the trap has not occurred, or that it occurred only
4203     // because of a transient condition during start-up in the interpreter.
4204     return false;
4205   }
4206   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : nullptr;
4207   if (md->has_trap_at(bci, m, reason) != 0) {
4208     // Assume PerBytecodeTrapLimit==0, for a more conservative heuristic.
4209     // Also, if there are multiple reasons, or if there is no per-BCI record,
4210     // assume the worst.
4211     if (log())
4212       log()->elem("observe trap='%s' count='%d'",
4213                   Deoptimization::trap_reason_name(reason),
4214                   md->trap_count(reason));
4215     return true;
4216   } else {
4217     // Ignore method/bci and see if there have been too many globally.
4218     return too_many_traps(reason, md);
4219   }
4220 }
4221 
4222 // Less-accurate variant which does not require a method and bci.
4223 bool Compile::too_many_traps(Deoptimization::DeoptReason reason,
4224                              ciMethodData* logmd) {
4225   if (trap_count(reason) >= Deoptimization::per_method_trap_limit(reason)) {
4226     // Too many traps globally.
4227     // Note that we use cumulative trap_count, not just md->trap_count.
4228     if (log()) {
4229       int mcount = (logmd == nullptr)? -1: (int)logmd->trap_count(reason);
4230       log()->elem("observe trap='%s' count='0' mcount='%d' ccount='%d'",
4231                   Deoptimization::trap_reason_name(reason),
4232                   mcount, trap_count(reason));
4233     }
4234     return true;
4235   } else {
4236     // The coast is clear.
4237     return false;
4238   }
4239 }
4240 
4241 //--------------------------too_many_recompiles--------------------------------
4242 // Report if there are too many recompiles at the current method and bci.
4243 // Consults PerBytecodeRecompilationCutoff and PerMethodRecompilationCutoff.
4244 // Is not eager to return true, since this will cause the compiler to use
4245 // Action_none for a trap point, to avoid too many recompilations.
4246 bool Compile::too_many_recompiles(ciMethod* method,
4247                                   int bci,
4248                                   Deoptimization::DeoptReason reason) {
4249   ciMethodData* md = method->method_data();
4250   if (md->is_empty()) {
4251     // Assume the trap has not occurred, or that it occurred only
4252     // because of a transient condition during start-up in the interpreter.
4253     return false;
4254   }
4255   // Pick a cutoff point well within PerBytecodeRecompilationCutoff.
4256   uint bc_cutoff = (uint) PerBytecodeRecompilationCutoff / 8;
4257   uint m_cutoff  = (uint) PerMethodRecompilationCutoff / 2 + 1;  // not zero
4258   Deoptimization::DeoptReason per_bc_reason
4259     = Deoptimization::reason_recorded_per_bytecode_if_any(reason);
4260   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? this->method() : nullptr;
4261   if ((per_bc_reason == Deoptimization::Reason_none
4262        || md->has_trap_at(bci, m, reason) != 0)
4263       // The trap frequency measure we care about is the recompile count:
4264       && md->trap_recompiled_at(bci, m)
4265       && md->overflow_recompile_count() >= bc_cutoff) {
4266     // Do not emit a trap here if it has already caused recompilations.
4267     // Also, if there are multiple reasons, or if there is no per-BCI record,
4268     // assume the worst.
4269     if (log())
4270       log()->elem("observe trap='%s recompiled' count='%d' recompiles2='%d'",
4271                   Deoptimization::trap_reason_name(reason),
4272                   md->trap_count(reason),
4273                   md->overflow_recompile_count());
4274     return true;
4275   } else if (trap_count(reason) != 0
4276              && decompile_count() >= m_cutoff) {
4277     // Too many recompiles globally, and we have seen this sort of trap.
4278     // Use cumulative decompile_count, not just md->decompile_count.
4279     if (log())
4280       log()->elem("observe trap='%s' count='%d' mcount='%d' decompiles='%d' mdecompiles='%d'",
4281                   Deoptimization::trap_reason_name(reason),
4282                   md->trap_count(reason), trap_count(reason),
4283                   md->decompile_count(), decompile_count());
4284     return true;
4285   } else {
4286     // The coast is clear.
4287     return false;
4288   }
4289 }
4290 
4291 // Compute when not to trap. Used by matching trap based nodes and
4292 // NullCheck optimization.
4293 void Compile::set_allowed_deopt_reasons() {
4294   _allowed_reasons = 0;
4295   if (is_method_compilation()) {
4296     for (int rs = (int)Deoptimization::Reason_none+1; rs < Compile::trapHistLength; rs++) {
4297       assert(rs < BitsPerInt, "recode bit map");
4298       if (!too_many_traps((Deoptimization::DeoptReason) rs)) {
4299         _allowed_reasons |= nth_bit(rs);
4300       }
4301     }
4302   }
4303 }
4304 
4305 bool Compile::needs_clinit_barrier(ciMethod* method, ciMethod* accessing_method) {
4306   return method->is_static() && needs_clinit_barrier(method->holder(), accessing_method);
4307 }
4308 
4309 bool Compile::needs_clinit_barrier(ciField* field, ciMethod* accessing_method) {
4310   return field->is_static() && needs_clinit_barrier(field->holder(), accessing_method);
4311 }
4312 
4313 bool Compile::needs_clinit_barrier(ciInstanceKlass* holder, ciMethod* accessing_method) {
4314   if (holder->is_initialized()) {
4315     return false;
4316   }
4317   if (holder->is_being_initialized()) {
4318     if (accessing_method->holder() == holder) {
4319       // Access inside a class. The barrier can be elided when access happens in <clinit>,
4320       // <init>, or a static method. In all those cases, there was an initialization
4321       // barrier on the holder klass passed.
4322       if (accessing_method->is_static_initializer() ||
4323           accessing_method->is_object_initializer() ||
4324           accessing_method->is_static()) {
4325         return false;
4326       }
4327     } else if (accessing_method->holder()->is_subclass_of(holder)) {
4328       // Access from a subclass. The barrier can be elided only when access happens in <clinit>.
4329       // In case of <init> or a static method, the barrier is on the subclass is not enough:
4330       // child class can become fully initialized while its parent class is still being initialized.
4331       if (accessing_method->is_static_initializer()) {
4332         return false;
4333       }
4334     }
4335     ciMethod* root = method(); // the root method of compilation
4336     if (root != accessing_method) {
4337       return needs_clinit_barrier(holder, root); // check access in the context of compilation root
4338     }
4339   }
4340   return true;
4341 }
4342 
4343 #ifndef PRODUCT
4344 //------------------------------verify_bidirectional_edges---------------------
4345 // For each input edge to a node (ie - for each Use-Def edge), verify that
4346 // there is a corresponding Def-Use edge.
4347 void Compile::verify_bidirectional_edges(Unique_Node_List& visited, const Unique_Node_List* root_and_safepoints) const {
4348   // Allocate stack of size C->live_nodes()/16 to avoid frequent realloc
4349   uint stack_size = live_nodes() >> 4;
4350   Node_List nstack(MAX2(stack_size, (uint) OptoNodeListSize));
4351   if (root_and_safepoints != nullptr) {
4352     assert(root_and_safepoints->member(_root), "root is not in root_and_safepoints");
4353     for (uint i = 0, limit = root_and_safepoints->size(); i < limit; i++) {
4354       Node* root_or_safepoint = root_and_safepoints->at(i);
4355       // If the node is a safepoint, let's check if it still has a control input
4356       // Lack of control input signifies that this node was killed by CCP or
4357       // recursively by remove_globally_dead_node and it shouldn't be a starting
4358       // point.
4359       if (!root_or_safepoint->is_SafePoint() || root_or_safepoint->in(0) != nullptr) {
4360         nstack.push(root_or_safepoint);
4361       }
4362     }
4363   } else {
4364     nstack.push(_root);
4365   }
4366 
4367   while (nstack.size() > 0) {
4368     Node* n = nstack.pop();
4369     if (visited.member(n)) {
4370       continue;
4371     }
4372     visited.push(n);
4373 
4374     // Walk over all input edges, checking for correspondence
4375     uint length = n->len();
4376     for (uint i = 0; i < length; i++) {
4377       Node* in = n->in(i);
4378       if (in != nullptr && !visited.member(in)) {
4379         nstack.push(in); // Put it on stack
4380       }
4381       if (in != nullptr && !in->is_top()) {
4382         // Count instances of `next`
4383         int cnt = 0;
4384         for (uint idx = 0; idx < in->_outcnt; idx++) {
4385           if (in->_out[idx] == n) {
4386             cnt++;
4387           }
4388         }
4389         assert(cnt > 0, "Failed to find Def-Use edge.");
4390         // Check for duplicate edges
4391         // walk the input array downcounting the input edges to n
4392         for (uint j = 0; j < length; j++) {
4393           if (n->in(j) == in) {
4394             cnt--;
4395           }
4396         }
4397         assert(cnt == 0, "Mismatched edge count.");
4398       } else if (in == nullptr) {
4399         assert(i == 0 || i >= n->req() ||
4400                n->is_Region() || n->is_Phi() || n->is_ArrayCopy() ||
4401                (n->is_Unlock() && i == (n->req() - 1)) ||
4402                (n->is_MemBar() && i == 5), // the precedence edge to a membar can be removed during macro node expansion
4403               "only region, phi, arraycopy, unlock or membar nodes have null data edges");
4404       } else {
4405         assert(in->is_top(), "sanity");
4406         // Nothing to check.
4407       }
4408     }
4409   }
4410 }
4411 
4412 //------------------------------verify_graph_edges---------------------------
4413 // Walk the Graph and verify that there is a one-to-one correspondence
4414 // between Use-Def edges and Def-Use edges in the graph.
4415 void Compile::verify_graph_edges(bool no_dead_code, const Unique_Node_List* root_and_safepoints) const {
4416   if (VerifyGraphEdges) {
4417     Unique_Node_List visited;
4418 
4419     // Call graph walk to check edges
4420     verify_bidirectional_edges(visited, root_and_safepoints);
4421     if (no_dead_code) {
4422       // Now make sure that no visited node is used by an unvisited node.
4423       bool dead_nodes = false;
4424       Unique_Node_List checked;
4425       while (visited.size() > 0) {
4426         Node* n = visited.pop();
4427         checked.push(n);
4428         for (uint i = 0; i < n->outcnt(); i++) {
4429           Node* use = n->raw_out(i);
4430           if (checked.member(use))  continue;  // already checked
4431           if (visited.member(use))  continue;  // already in the graph
4432           if (use->is_Con())        continue;  // a dead ConNode is OK
4433           // At this point, we have found a dead node which is DU-reachable.
4434           if (!dead_nodes) {
4435             tty->print_cr("*** Dead nodes reachable via DU edges:");
4436             dead_nodes = true;
4437           }
4438           use->dump(2);
4439           tty->print_cr("---");
4440           checked.push(use);  // No repeats; pretend it is now checked.
4441         }
4442       }
4443       assert(!dead_nodes, "using nodes must be reachable from root");
4444     }
4445   }
4446 }
4447 #endif
4448 
4449 // The Compile object keeps track of failure reasons separately from the ciEnv.
4450 // This is required because there is not quite a 1-1 relation between the
4451 // ciEnv and its compilation task and the Compile object.  Note that one
4452 // ciEnv might use two Compile objects, if C2Compiler::compile_method decides
4453 // to backtrack and retry without subsuming loads.  Other than this backtracking
4454 // behavior, the Compile's failure reason is quietly copied up to the ciEnv
4455 // by the logic in C2Compiler.
4456 void Compile::record_failure(const char* reason DEBUG_ONLY(COMMA bool allow_multiple_failures)) {
4457   if (log() != nullptr) {
4458     log()->elem("failure reason='%s' phase='compile'", reason);
4459   }
4460   if (_failure_reason.get() == nullptr) {
4461     // Record the first failure reason.
4462     _failure_reason.set(reason);
4463     if (CaptureBailoutInformation) {
4464       _first_failure_details = new CompilationFailureInfo(reason);
4465     }
4466   } else {
4467     assert(!StressBailout || allow_multiple_failures, "should have handled previous failure.");
4468   }
4469 
4470   if (!C->failure_reason_is(C2Compiler::retry_no_subsuming_loads())) {
4471     C->print_method(PHASE_FAILURE, 1);
4472   }
4473   _root = nullptr;  // flush the graph, too
4474 }
4475 
4476 Compile::TracePhase::TracePhase(const char* name, PhaseTraceId id)
4477   : TraceTime(name, &Phase::timers[id], CITime, CITimeVerbose),
4478     _compile(Compile::current()),
4479     _log(nullptr),
4480     _dolog(CITimeVerbose)
4481 {
4482   assert(_compile != nullptr, "sanity check");
4483   assert(id != PhaseTraceId::_t_none, "Don't use none");
4484   if (_dolog) {
4485     _log = _compile->log();
4486   }
4487   if (_log != nullptr) {
4488     _log->begin_head("phase name='%s' nodes='%d' live='%d'", phase_name(), _compile->unique(), _compile->live_nodes());
4489     _log->stamp();
4490     _log->end_head();
4491   }
4492 
4493   // Inform memory statistic, if enabled
4494   if (CompilationMemoryStatistic::enabled()) {
4495     CompilationMemoryStatistic::on_phase_start((int)id, name);
4496   }
4497 }
4498 
4499 Compile::TracePhase::TracePhase(PhaseTraceId id)
4500   : TracePhase(Phase::get_phase_trace_id_text(id), id) {}
4501 
4502 Compile::TracePhase::~TracePhase() {
4503 
4504   // Inform memory statistic, if enabled
4505   if (CompilationMemoryStatistic::enabled()) {
4506     CompilationMemoryStatistic::on_phase_end();
4507   }
4508 
4509   if (_compile->failing_internal()) {
4510     if (_log != nullptr) {
4511       _log->done("phase");
4512     }
4513     return; // timing code, not stressing bailouts.
4514   }
4515 #ifdef ASSERT
4516   if (PrintIdealNodeCount) {
4517     tty->print_cr("phase name='%s' nodes='%d' live='%d' live_graph_walk='%d'",
4518                   phase_name(), _compile->unique(), _compile->live_nodes(), _compile->count_live_nodes_by_graph_walk());
4519   }
4520 
4521   if (VerifyIdealNodeCount) {
4522     _compile->print_missing_nodes();
4523   }
4524 #endif
4525 
4526   if (_log != nullptr) {
4527     _log->done("phase name='%s' nodes='%d' live='%d'", phase_name(), _compile->unique(), _compile->live_nodes());
4528   }
4529 }
4530 
4531 //----------------------------static_subtype_check-----------------------------
4532 // Shortcut important common cases when superklass is exact:
4533 // (0) superklass is java.lang.Object (can occur in reflective code)
4534 // (1) subklass is already limited to a subtype of superklass => always ok
4535 // (2) subklass does not overlap with superklass => always fail
4536 // (3) superklass has NO subtypes and we can check with a simple compare.
4537 Compile::SubTypeCheckResult Compile::static_subtype_check(const TypeKlassPtr* superk, const TypeKlassPtr* subk, bool skip) {
4538   if (skip) {
4539     return SSC_full_test;       // Let caller generate the general case.
4540   }
4541 
4542   if (subk->is_java_subtype_of(superk)) {
4543     return SSC_always_true; // (0) and (1)  this test cannot fail
4544   }
4545 
4546   if (!subk->maybe_java_subtype_of(superk)) {
4547     return SSC_always_false; // (2) true path dead; no dynamic test needed
4548   }
4549 
4550   const Type* superelem = superk;
4551   if (superk->isa_aryklassptr()) {
4552     int ignored;
4553     superelem = superk->is_aryklassptr()->base_element_type(ignored);
4554   }
4555 
4556   if (superelem->isa_instklassptr()) {
4557     ciInstanceKlass* ik = superelem->is_instklassptr()->instance_klass();
4558     if (!ik->has_subklass()) {
4559       if (!ik->is_final()) {
4560         // Add a dependency if there is a chance of a later subclass.
4561         dependencies()->assert_leaf_type(ik);
4562       }
4563       if (!superk->maybe_java_subtype_of(subk)) {
4564         return SSC_always_false;
4565       }
4566       return SSC_easy_test;     // (3) caller can do a simple ptr comparison
4567     }
4568   } else {
4569     // A primitive array type has no subtypes.
4570     return SSC_easy_test;       // (3) caller can do a simple ptr comparison
4571   }
4572 
4573   return SSC_full_test;
4574 }
4575 
4576 Node* Compile::conv_I2X_index(PhaseGVN* phase, Node* idx, const TypeInt* sizetype, Node* ctrl) {
4577 #ifdef _LP64
4578   // The scaled index operand to AddP must be a clean 64-bit value.
4579   // Java allows a 32-bit int to be incremented to a negative
4580   // value, which appears in a 64-bit register as a large
4581   // positive number.  Using that large positive number as an
4582   // operand in pointer arithmetic has bad consequences.
4583   // On the other hand, 32-bit overflow is rare, and the possibility
4584   // can often be excluded, if we annotate the ConvI2L node with
4585   // a type assertion that its value is known to be a small positive
4586   // number.  (The prior range check has ensured this.)
4587   // This assertion is used by ConvI2LNode::Ideal.
4588   int index_max = max_jint - 1;  // array size is max_jint, index is one less
4589   if (sizetype != nullptr && sizetype->_hi > 0) {
4590     index_max = sizetype->_hi - 1;
4591   }
4592   const TypeInt* iidxtype = TypeInt::make(0, index_max, Type::WidenMax);
4593   idx = constrained_convI2L(phase, idx, iidxtype, ctrl);
4594 #endif
4595   return idx;
4596 }
4597 
4598 // Convert integer value to a narrowed long type dependent on ctrl (for example, a range check)
4599 Node* Compile::constrained_convI2L(PhaseGVN* phase, Node* value, const TypeInt* itype, Node* ctrl, bool carry_dependency) {
4600   if (ctrl != nullptr) {
4601     // Express control dependency by a CastII node with a narrow type.
4602     // Make the CastII node dependent on the control input to prevent the narrowed ConvI2L
4603     // node from floating above the range check during loop optimizations. Otherwise, the
4604     // ConvI2L node may be eliminated independently of the range check, causing the data path
4605     // to become TOP while the control path is still there (although it's unreachable).
4606     value = new CastIINode(ctrl, value, itype, carry_dependency ? ConstraintCastNode::DependencyType::NonFloatingNarrowing : ConstraintCastNode::DependencyType::FloatingNarrowing, true /* range check dependency */);
4607     value = phase->transform(value);
4608   }
4609   const TypeLong* ltype = TypeLong::make(itype->_lo, itype->_hi, itype->_widen);
4610   return phase->transform(new ConvI2LNode(value, ltype));
4611 }
4612 
4613 void Compile::dump_print_inlining() {
4614   inline_printer()->print_on(tty);
4615 }
4616 
4617 void Compile::log_late_inline(CallGenerator* cg) {
4618   if (log() != nullptr) {
4619     log()->head("late_inline method='%d' inline_id='" JLONG_FORMAT "'", log()->identify(cg->method()),
4620                 cg->unique_id());
4621     JVMState* p = cg->call_node()->jvms();
4622     while (p != nullptr) {
4623       log()->elem("jvms bci='%d' method='%d'", p->bci(), log()->identify(p->method()));
4624       p = p->caller();
4625     }
4626     log()->tail("late_inline");
4627   }
4628 }
4629 
4630 void Compile::log_late_inline_failure(CallGenerator* cg, const char* msg) {
4631   log_late_inline(cg);
4632   if (log() != nullptr) {
4633     log()->inline_fail(msg);
4634   }
4635 }
4636 
4637 void Compile::log_inline_id(CallGenerator* cg) {
4638   if (log() != nullptr) {
4639     // The LogCompilation tool needs a unique way to identify late
4640     // inline call sites. This id must be unique for this call site in
4641     // this compilation. Try to have it unique across compilations as
4642     // well because it can be convenient when grepping through the log
4643     // file.
4644     // Distinguish OSR compilations from others in case CICountOSR is
4645     // on.
4646     jlong id = ((jlong)unique()) + (((jlong)compile_id()) << 33) + (CICountOSR && is_osr_compilation() ? ((jlong)1) << 32 : 0);
4647     cg->set_unique_id(id);
4648     log()->elem("inline_id id='" JLONG_FORMAT "'", id);
4649   }
4650 }
4651 
4652 void Compile::log_inline_failure(const char* msg) {
4653   if (C->log() != nullptr) {
4654     C->log()->inline_fail(msg);
4655   }
4656 }
4657 
4658 
4659 // Dump inlining replay data to the stream.
4660 // Don't change thread state and acquire any locks.
4661 void Compile::dump_inline_data(outputStream* out) {
4662   InlineTree* inl_tree = ilt();
4663   if (inl_tree != nullptr) {
4664     out->print(" inline %d", inl_tree->count());
4665     inl_tree->dump_replay_data(out);
4666   }
4667 }
4668 
4669 void Compile::dump_inline_data_reduced(outputStream* out) {
4670   assert(ReplayReduce, "");
4671 
4672   InlineTree* inl_tree = ilt();
4673   if (inl_tree == nullptr) {
4674     return;
4675   }
4676   // Enable iterative replay file reduction
4677   // Output "compile" lines for depth 1 subtrees,
4678   // simulating that those trees were compiled
4679   // instead of inlined.
4680   for (int i = 0; i < inl_tree->subtrees().length(); ++i) {
4681     InlineTree* sub = inl_tree->subtrees().at(i);
4682     if (sub->inline_level() != 1) {
4683       continue;
4684     }
4685 
4686     ciMethod* method = sub->method();
4687     int entry_bci = -1;
4688     int comp_level = env()->task()->comp_level();
4689     out->print("compile ");
4690     method->dump_name_as_ascii(out);
4691     out->print(" %d %d", entry_bci, comp_level);
4692     out->print(" inline %d", sub->count());
4693     sub->dump_replay_data(out, -1);
4694     out->cr();
4695   }
4696 }
4697 
4698 int Compile::cmp_expensive_nodes(Node* n1, Node* n2) {
4699   if (n1->Opcode() < n2->Opcode())      return -1;
4700   else if (n1->Opcode() > n2->Opcode()) return 1;
4701 
4702   assert(n1->req() == n2->req(), "can't compare %s nodes: n1->req() = %d, n2->req() = %d", NodeClassNames[n1->Opcode()], n1->req(), n2->req());
4703   for (uint i = 1; i < n1->req(); i++) {
4704     if (n1->in(i) < n2->in(i))      return -1;
4705     else if (n1->in(i) > n2->in(i)) return 1;
4706   }
4707 
4708   return 0;
4709 }
4710 
4711 int Compile::cmp_expensive_nodes(Node** n1p, Node** n2p) {
4712   Node* n1 = *n1p;
4713   Node* n2 = *n2p;
4714 
4715   return cmp_expensive_nodes(n1, n2);
4716 }
4717 
4718 void Compile::sort_expensive_nodes() {
4719   if (!expensive_nodes_sorted()) {
4720     _expensive_nodes.sort(cmp_expensive_nodes);
4721   }
4722 }
4723 
4724 bool Compile::expensive_nodes_sorted() const {
4725   for (int i = 1; i < _expensive_nodes.length(); i++) {
4726     if (cmp_expensive_nodes(_expensive_nodes.adr_at(i), _expensive_nodes.adr_at(i-1)) < 0) {
4727       return false;
4728     }
4729   }
4730   return true;
4731 }
4732 
4733 bool Compile::should_optimize_expensive_nodes(PhaseIterGVN &igvn) {
4734   if (_expensive_nodes.length() == 0) {
4735     return false;
4736   }
4737 
4738   assert(OptimizeExpensiveOps, "optimization off?");
4739 
4740   // Take this opportunity to remove dead nodes from the list
4741   int j = 0;
4742   for (int i = 0; i < _expensive_nodes.length(); i++) {
4743     Node* n = _expensive_nodes.at(i);
4744     if (!n->is_unreachable(igvn)) {
4745       assert(n->is_expensive(), "should be expensive");
4746       _expensive_nodes.at_put(j, n);
4747       j++;
4748     }
4749   }
4750   _expensive_nodes.trunc_to(j);
4751 
4752   // Then sort the list so that similar nodes are next to each other
4753   // and check for at least two nodes of identical kind with same data
4754   // inputs.
4755   sort_expensive_nodes();
4756 
4757   for (int i = 0; i < _expensive_nodes.length()-1; i++) {
4758     if (cmp_expensive_nodes(_expensive_nodes.adr_at(i), _expensive_nodes.adr_at(i+1)) == 0) {
4759       return true;
4760     }
4761   }
4762 
4763   return false;
4764 }
4765 
4766 void Compile::cleanup_expensive_nodes(PhaseIterGVN &igvn) {
4767   if (_expensive_nodes.length() == 0) {
4768     return;
4769   }
4770 
4771   assert(OptimizeExpensiveOps, "optimization off?");
4772 
4773   // Sort to bring similar nodes next to each other and clear the
4774   // control input of nodes for which there's only a single copy.
4775   sort_expensive_nodes();
4776 
4777   int j = 0;
4778   int identical = 0;
4779   int i = 0;
4780   bool modified = false;
4781   for (; i < _expensive_nodes.length()-1; i++) {
4782     assert(j <= i, "can't write beyond current index");
4783     if (_expensive_nodes.at(i)->Opcode() == _expensive_nodes.at(i+1)->Opcode()) {
4784       identical++;
4785       _expensive_nodes.at_put(j++, _expensive_nodes.at(i));
4786       continue;
4787     }
4788     if (identical > 0) {
4789       _expensive_nodes.at_put(j++, _expensive_nodes.at(i));
4790       identical = 0;
4791     } else {
4792       Node* n = _expensive_nodes.at(i);
4793       igvn.replace_input_of(n, 0, nullptr);
4794       igvn.hash_insert(n);
4795       modified = true;
4796     }
4797   }
4798   if (identical > 0) {
4799     _expensive_nodes.at_put(j++, _expensive_nodes.at(i));
4800   } else if (_expensive_nodes.length() >= 1) {
4801     Node* n = _expensive_nodes.at(i);
4802     igvn.replace_input_of(n, 0, nullptr);
4803     igvn.hash_insert(n);
4804     modified = true;
4805   }
4806   _expensive_nodes.trunc_to(j);
4807   if (modified) {
4808     igvn.optimize();
4809   }
4810 }
4811 
4812 void Compile::add_expensive_node(Node * n) {
4813   assert(!_expensive_nodes.contains(n), "duplicate entry in expensive list");
4814   assert(n->is_expensive(), "expensive nodes with non-null control here only");
4815   assert(!n->is_CFG() && !n->is_Mem(), "no cfg or memory nodes here");
4816   if (OptimizeExpensiveOps) {
4817     _expensive_nodes.append(n);
4818   } else {
4819     // Clear control input and let IGVN optimize expensive nodes if
4820     // OptimizeExpensiveOps is off.
4821     n->set_req(0, nullptr);
4822   }
4823 }
4824 
4825 /**
4826  * Track coarsened Lock and Unlock nodes.
4827  */
4828 
4829 class Lock_List : public Node_List {
4830   uint _origin_cnt;
4831 public:
4832   Lock_List(Arena *a, uint cnt) : Node_List(a), _origin_cnt(cnt) {}
4833   uint origin_cnt() const { return _origin_cnt; }
4834 };
4835 
4836 void Compile::add_coarsened_locks(GrowableArray<AbstractLockNode*>& locks) {
4837   int length = locks.length();
4838   if (length > 0) {
4839     // Have to keep this list until locks elimination during Macro nodes elimination.
4840     Lock_List* locks_list = new (comp_arena()) Lock_List(comp_arena(), length);
4841     AbstractLockNode* alock = locks.at(0);
4842     BoxLockNode* box = alock->box_node()->as_BoxLock();
4843     for (int i = 0; i < length; i++) {
4844       AbstractLockNode* lock = locks.at(i);
4845       assert(lock->is_coarsened(), "expecting only coarsened AbstractLock nodes, but got '%s'[%d] node", lock->Name(), lock->_idx);
4846       locks_list->push(lock);
4847       BoxLockNode* this_box = lock->box_node()->as_BoxLock();
4848       if (this_box != box) {
4849         // Locking regions (BoxLock) could be Unbalanced here:
4850         //  - its coarsened locks were eliminated in earlier
4851         //    macro nodes elimination followed by loop unroll
4852         //  - it is OSR locking region (no Lock node)
4853         // Preserve Unbalanced status in such cases.
4854         if (!this_box->is_unbalanced()) {
4855           this_box->set_coarsened();
4856         }
4857         if (!box->is_unbalanced()) {
4858           box->set_coarsened();
4859         }
4860       }
4861     }
4862     _coarsened_locks.append(locks_list);
4863   }
4864 }
4865 
4866 void Compile::remove_useless_coarsened_locks(Unique_Node_List& useful) {
4867   int count = coarsened_count();
4868   for (int i = 0; i < count; i++) {
4869     Node_List* locks_list = _coarsened_locks.at(i);
4870     for (uint j = 0; j < locks_list->size(); j++) {
4871       Node* lock = locks_list->at(j);
4872       assert(lock->is_AbstractLock(), "sanity");
4873       if (!useful.member(lock)) {
4874         locks_list->yank(lock);
4875       }
4876     }
4877   }
4878 }
4879 
4880 void Compile::remove_coarsened_lock(Node* n) {
4881   if (n->is_AbstractLock()) {
4882     int count = coarsened_count();
4883     for (int i = 0; i < count; i++) {
4884       Node_List* locks_list = _coarsened_locks.at(i);
4885       locks_list->yank(n);
4886     }
4887   }
4888 }
4889 
4890 bool Compile::coarsened_locks_consistent() {
4891   int count = coarsened_count();
4892   for (int i = 0; i < count; i++) {
4893     bool unbalanced = false;
4894     bool modified = false; // track locks kind modifications
4895     Lock_List* locks_list = (Lock_List*)_coarsened_locks.at(i);
4896     uint size = locks_list->size();
4897     if (size == 0) {
4898       unbalanced = false; // All locks were eliminated - good
4899     } else if (size != locks_list->origin_cnt()) {
4900       unbalanced = true; // Some locks were removed from list
4901     } else {
4902       for (uint j = 0; j < size; j++) {
4903         Node* lock = locks_list->at(j);
4904         // All nodes in group should have the same state (modified or not)
4905         if (!lock->as_AbstractLock()->is_coarsened()) {
4906           if (j == 0) {
4907             // first on list was modified, the rest should be too for consistency
4908             modified = true;
4909           } else if (!modified) {
4910             // this lock was modified but previous locks on the list were not
4911             unbalanced = true;
4912             break;
4913           }
4914         } else if (modified) {
4915           // previous locks on list were modified but not this lock
4916           unbalanced = true;
4917           break;
4918         }
4919       }
4920     }
4921     if (unbalanced) {
4922       // unbalanced monitor enter/exit - only some [un]lock nodes were removed or modified
4923 #ifdef ASSERT
4924       if (PrintEliminateLocks) {
4925         tty->print_cr("=== unbalanced coarsened locks ===");
4926         for (uint l = 0; l < size; l++) {
4927           locks_list->at(l)->dump();
4928         }
4929       }
4930 #endif
4931       record_failure(C2Compiler::retry_no_locks_coarsening());
4932       return false;
4933     }
4934   }
4935   return true;
4936 }
4937 
4938 // Mark locking regions (identified by BoxLockNode) as unbalanced if
4939 // locks coarsening optimization removed Lock/Unlock nodes from them.
4940 // Such regions become unbalanced because coarsening only removes part
4941 // of Lock/Unlock nodes in region. As result we can't execute other
4942 // locks elimination optimizations which assume all code paths have
4943 // corresponding pair of Lock/Unlock nodes - they are balanced.
4944 void Compile::mark_unbalanced_boxes() const {
4945   int count = coarsened_count();
4946   for (int i = 0; i < count; i++) {
4947     Node_List* locks_list = _coarsened_locks.at(i);
4948     uint size = locks_list->size();
4949     if (size > 0) {
4950       AbstractLockNode* alock = locks_list->at(0)->as_AbstractLock();
4951       BoxLockNode* box = alock->box_node()->as_BoxLock();
4952       if (alock->is_coarsened()) {
4953         // coarsened_locks_consistent(), which is called before this method, verifies
4954         // that the rest of Lock/Unlock nodes on locks_list are also coarsened.
4955         assert(!box->is_eliminated(), "regions with coarsened locks should not be marked as eliminated");
4956         for (uint j = 1; j < size; j++) {
4957           assert(locks_list->at(j)->as_AbstractLock()->is_coarsened(), "only coarsened locks are expected here");
4958           BoxLockNode* this_box = locks_list->at(j)->as_AbstractLock()->box_node()->as_BoxLock();
4959           if (box != this_box) {
4960             assert(!this_box->is_eliminated(), "regions with coarsened locks should not be marked as eliminated");
4961             box->set_unbalanced();
4962             this_box->set_unbalanced();
4963           }
4964         }
4965       }
4966     }
4967   }
4968 }
4969 
4970 /**
4971  * Remove the speculative part of types and clean up the graph
4972  */
4973 void Compile::remove_speculative_types(PhaseIterGVN &igvn) {
4974   if (UseTypeSpeculation) {
4975     Unique_Node_List worklist;
4976     worklist.push(root());
4977     int modified = 0;
4978     // Go over all type nodes that carry a speculative type, drop the
4979     // speculative part of the type and enqueue the node for an igvn
4980     // which may optimize it out.
4981     for (uint next = 0; next < worklist.size(); ++next) {
4982       Node *n  = worklist.at(next);
4983       if (n->is_Type()) {
4984         TypeNode* tn = n->as_Type();
4985         const Type* t = tn->type();
4986         const Type* t_no_spec = t->remove_speculative();
4987         if (t_no_spec != t) {
4988           bool in_hash = igvn.hash_delete(n);
4989           assert(in_hash || n->hash() == Node::NO_HASH, "node should be in igvn hash table");
4990           tn->set_type(t_no_spec);
4991           igvn.hash_insert(n);
4992           igvn._worklist.push(n); // give it a chance to go away
4993           modified++;
4994         }
4995       }
4996       // Iterate over outs - endless loops is unreachable from below
4997       for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
4998         Node *m = n->fast_out(i);
4999         if (not_a_node(m)) {
5000           continue;
5001         }
5002         worklist.push(m);
5003       }
5004     }
5005     // Drop the speculative part of all types in the igvn's type table
5006     igvn.remove_speculative_types();
5007     if (modified > 0) {
5008       igvn.optimize();
5009       if (failing())  return;
5010     }
5011 #ifdef ASSERT
5012     // Verify that after the IGVN is over no speculative type has resurfaced
5013     worklist.clear();
5014     worklist.push(root());
5015     for (uint next = 0; next < worklist.size(); ++next) {
5016       Node *n  = worklist.at(next);
5017       const Type* t = igvn.type_or_null(n);
5018       assert((t == nullptr) || (t == t->remove_speculative()), "no more speculative types");
5019       if (n->is_Type()) {
5020         t = n->as_Type()->type();
5021         assert(t == t->remove_speculative(), "no more speculative types");
5022       }
5023       // Iterate over outs - endless loops is unreachable from below
5024       for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
5025         Node *m = n->fast_out(i);
5026         if (not_a_node(m)) {
5027           continue;
5028         }
5029         worklist.push(m);
5030       }
5031     }
5032     igvn.check_no_speculative_types();
5033 #endif
5034   }
5035 }
5036 
5037 // Auxiliary methods to support randomized stressing/fuzzing.
5038 
5039 void Compile::initialize_stress_seed(const DirectiveSet* directive) {
5040   if (FLAG_IS_DEFAULT(StressSeed) || (FLAG_IS_ERGO(StressSeed) && directive->RepeatCompilationOption)) {
5041     _stress_seed = static_cast<uint>(Ticks::now().nanoseconds());
5042     FLAG_SET_ERGO(StressSeed, _stress_seed);
5043   } else {
5044     _stress_seed = StressSeed;
5045   }
5046   if (_log != nullptr) {
5047     _log->elem("stress_test seed='%u'", _stress_seed);
5048   }
5049 }
5050 
5051 int Compile::random() {
5052   _stress_seed = os::next_random(_stress_seed);
5053   return static_cast<int>(_stress_seed);
5054 }
5055 
5056 // This method can be called the arbitrary number of times, with current count
5057 // as the argument. The logic allows selecting a single candidate from the
5058 // running list of candidates as follows:
5059 //    int count = 0;
5060 //    Cand* selected = null;
5061 //    while(cand = cand->next()) {
5062 //      if (randomized_select(++count)) {
5063 //        selected = cand;
5064 //      }
5065 //    }
5066 //
5067 // Including count equalizes the chances any candidate is "selected".
5068 // This is useful when we don't have the complete list of candidates to choose
5069 // from uniformly. In this case, we need to adjust the randomicity of the
5070 // selection, or else we will end up biasing the selection towards the latter
5071 // candidates.
5072 //
5073 // Quick back-envelope calculation shows that for the list of n candidates
5074 // the equal probability for the candidate to persist as "best" can be
5075 // achieved by replacing it with "next" k-th candidate with the probability
5076 // of 1/k. It can be easily shown that by the end of the run, the
5077 // probability for any candidate is converged to 1/n, thus giving the
5078 // uniform distribution among all the candidates.
5079 //
5080 // We don't care about the domain size as long as (RANDOMIZED_DOMAIN / count) is large.
5081 #define RANDOMIZED_DOMAIN_POW 29
5082 #define RANDOMIZED_DOMAIN (1 << RANDOMIZED_DOMAIN_POW)
5083 #define RANDOMIZED_DOMAIN_MASK ((1 << (RANDOMIZED_DOMAIN_POW + 1)) - 1)
5084 bool Compile::randomized_select(int count) {
5085   assert(count > 0, "only positive");
5086   return (random() & RANDOMIZED_DOMAIN_MASK) < (RANDOMIZED_DOMAIN / count);
5087 }
5088 
5089 #ifdef ASSERT
5090 // Failures are geometrically distributed with probability 1/StressBailoutMean.
5091 bool Compile::fail_randomly() {
5092   if ((random() % StressBailoutMean) != 0) {
5093     return false;
5094   }
5095   record_failure("StressBailout");
5096   return true;
5097 }
5098 
5099 bool Compile::failure_is_artificial() {
5100   return C->failure_reason_is("StressBailout");
5101 }
5102 #endif
5103 
5104 CloneMap&     Compile::clone_map()                 { return _clone_map; }
5105 void          Compile::set_clone_map(Dict* d)      { _clone_map._dict = d; }
5106 
5107 void NodeCloneInfo::dump_on(outputStream* st) const {
5108   st->print(" {%d:%d} ", idx(), gen());
5109 }
5110 
5111 void CloneMap::clone(Node* old, Node* nnn, int gen) {
5112   uint64_t val = value(old->_idx);
5113   NodeCloneInfo cio(val);
5114   assert(val != 0, "old node should be in the map");
5115   NodeCloneInfo cin(cio.idx(), gen + cio.gen());
5116   insert(nnn->_idx, cin.get());
5117 #ifndef PRODUCT
5118   if (is_debug()) {
5119     tty->print_cr("CloneMap::clone inserted node %d info {%d:%d} into CloneMap", nnn->_idx, cin.idx(), cin.gen());
5120   }
5121 #endif
5122 }
5123 
5124 void CloneMap::verify_insert_and_clone(Node* old, Node* nnn, int gen) {
5125   NodeCloneInfo cio(value(old->_idx));
5126   if (cio.get() == 0) {
5127     cio.set(old->_idx, 0);
5128     insert(old->_idx, cio.get());
5129 #ifndef PRODUCT
5130     if (is_debug()) {
5131       tty->print_cr("CloneMap::verify_insert_and_clone inserted node %d info {%d:%d} into CloneMap", old->_idx, cio.idx(), cio.gen());
5132     }
5133 #endif
5134   }
5135   clone(old, nnn, gen);
5136 }
5137 
5138 int CloneMap::max_gen() const {
5139   int g = 0;
5140   DictI di(_dict);
5141   for(; di.test(); ++di) {
5142     int t = gen(di._key);
5143     if (g < t) {
5144       g = t;
5145 #ifndef PRODUCT
5146       if (is_debug()) {
5147         tty->print_cr("CloneMap::max_gen() update max=%d from %d", g, _2_node_idx_t(di._key));
5148       }
5149 #endif
5150     }
5151   }
5152   return g;
5153 }
5154 
5155 void CloneMap::dump(node_idx_t key, outputStream* st) const {
5156   uint64_t val = value(key);
5157   if (val != 0) {
5158     NodeCloneInfo ni(val);
5159     ni.dump_on(st);
5160   }
5161 }
5162 
5163 void Compile::shuffle_macro_nodes() {
5164   shuffle_array(*C, _macro_nodes);
5165 }
5166 
5167 // Move Allocate nodes to the start of the list
5168 void Compile::sort_macro_nodes() {
5169   int count = macro_count();
5170   int allocates = 0;
5171   for (int i = 0; i < count; i++) {
5172     Node* n = macro_node(i);
5173     if (n->is_Allocate()) {
5174       if (i != allocates) {
5175         Node* tmp = macro_node(allocates);
5176         _macro_nodes.at_put(allocates, n);
5177         _macro_nodes.at_put(i, tmp);
5178       }
5179       allocates++;
5180     }
5181   }
5182 }
5183 
5184 void Compile::print_method(CompilerPhaseType compile_phase, int level, Node* n) {
5185   if (failing_internal()) { return; } // failing_internal to not stress bailouts from printing code.
5186   EventCompilerPhase event(UNTIMED);
5187   if (event.should_commit()) {
5188     CompilerEvent::PhaseEvent::post(event, C->_latest_stage_start_counter, compile_phase, C->_compile_id, level);
5189   }
5190 #ifndef PRODUCT
5191   ResourceMark rm;
5192   stringStream ss;
5193   ss.print_raw(CompilerPhaseTypeHelper::to_description(compile_phase));
5194   int iter = ++_igv_phase_iter[compile_phase];
5195   if (iter > 1) {
5196     ss.print(" %d", iter);
5197   }
5198   if (n != nullptr) {
5199     ss.print(": %d %s", n->_idx, NodeClassNames[n->Opcode()]);
5200     if (n->is_Call()) {
5201       CallNode* call = n->as_Call();
5202       if (call->_name != nullptr) {
5203         // E.g. uncommon traps etc.
5204         ss.print(" - %s", call->_name);
5205       } else if (call->is_CallJava()) {
5206         CallJavaNode* call_java = call->as_CallJava();
5207         if (call_java->method() != nullptr) {
5208           ss.print(" -");
5209           call_java->method()->print_short_name(&ss);
5210         }
5211       }
5212     }
5213   }
5214 
5215   const char* name = ss.as_string();
5216   if (should_print_igv(level)) {
5217     _igv_printer->print_graph(name);
5218   }
5219   if (should_print_phase(level)) {
5220     print_phase(name);
5221   }
5222   if (should_print_ideal_phase(compile_phase)) {
5223     print_ideal_ir(CompilerPhaseTypeHelper::to_name(compile_phase));
5224   }
5225 #endif
5226   C->_latest_stage_start_counter.stamp();
5227 }
5228 
5229 // Only used from CompileWrapper
5230 void Compile::begin_method() {
5231 #ifndef PRODUCT
5232   if (_method != nullptr && should_print_igv(1)) {
5233     _igv_printer->begin_method();
5234   }
5235 #endif
5236   C->_latest_stage_start_counter.stamp();
5237 }
5238 
5239 // Only used from CompileWrapper
5240 void Compile::end_method() {
5241   EventCompilerPhase event(UNTIMED);
5242   if (event.should_commit()) {
5243     CompilerEvent::PhaseEvent::post(event, C->_latest_stage_start_counter, PHASE_END, C->_compile_id, 1);
5244   }
5245 
5246 #ifndef PRODUCT
5247   if (_method != nullptr && should_print_igv(1)) {
5248     _igv_printer->end_method();
5249   }
5250 #endif
5251 }
5252 
5253 #ifndef PRODUCT
5254 bool Compile::should_print_phase(const int level) const {
5255   return PrintPhaseLevel >= 0 && directive()->PhasePrintLevelOption >= level &&
5256          _method != nullptr; // Do not print phases for stubs.
5257 }
5258 
5259 bool Compile::should_print_ideal_phase(CompilerPhaseType cpt) const {
5260   return _directive->should_print_ideal_phase(cpt);
5261 }
5262 
5263 void Compile::init_igv() {
5264   if (_igv_printer == nullptr) {
5265     _igv_printer = IdealGraphPrinter::printer();
5266     _igv_printer->set_compile(this);
5267   }
5268 }
5269 
5270 bool Compile::should_print_igv(const int level) {
5271   PRODUCT_RETURN_(return false;);
5272 
5273   if (PrintIdealGraphLevel < 0) { // disabled by the user
5274     return false;
5275   }
5276 
5277   bool need = directive()->IGVPrintLevelOption >= level;
5278   if (need) {
5279     Compile::init_igv();
5280   }
5281   return need;
5282 }
5283 
5284 IdealGraphPrinter* Compile::_debug_file_printer = nullptr;
5285 IdealGraphPrinter* Compile::_debug_network_printer = nullptr;
5286 
5287 // Called from debugger. Prints method to the default file with the default phase name.
5288 // This works regardless of any Ideal Graph Visualizer flags set or not.
5289 // Use in debugger (gdb/rr): p igv_print($sp, $fp, $pc).
5290 void igv_print(void* sp, void* fp, void* pc) {
5291   frame fr(sp, fp, pc);
5292   Compile::current()->igv_print_method_to_file(nullptr, false, &fr);
5293 }
5294 
5295 // Same as igv_print() above but with a specified phase name.
5296 void igv_print(const char* phase_name, void* sp, void* fp, void* pc) {
5297   frame fr(sp, fp, pc);
5298   Compile::current()->igv_print_method_to_file(phase_name, false, &fr);
5299 }
5300 
5301 // Called from debugger. Prints method with the default phase name to the default network or the one specified with
5302 // the network flags for the Ideal Graph Visualizer, or to the default file depending on the 'network' argument.
5303 // This works regardless of any Ideal Graph Visualizer flags set or not.
5304 // Use in debugger (gdb/rr): p igv_print(true, $sp, $fp, $pc).
5305 void igv_print(bool network, void* sp, void* fp, void* pc) {
5306   frame fr(sp, fp, pc);
5307   if (network) {
5308     Compile::current()->igv_print_method_to_network(nullptr, &fr);
5309   } else {
5310     Compile::current()->igv_print_method_to_file(nullptr, false, &fr);
5311   }
5312 }
5313 
5314 // Same as igv_print(bool network, ...) above but with a specified phase name.
5315 // Use in debugger (gdb/rr): p igv_print(true, "MyPhase", $sp, $fp, $pc).
5316 void igv_print(bool network, const char* phase_name, void* sp, void* fp, void* pc) {
5317   frame fr(sp, fp, pc);
5318   if (network) {
5319     Compile::current()->igv_print_method_to_network(phase_name, &fr);
5320   } else {
5321     Compile::current()->igv_print_method_to_file(phase_name, false, &fr);
5322   }
5323 }
5324 
5325 // Called from debugger. Normal write to the default _printer. Only works if Ideal Graph Visualizer printing flags are set.
5326 void igv_print_default() {
5327   Compile::current()->print_method(PHASE_DEBUG, 0);
5328 }
5329 
5330 // Called from debugger, especially when replaying a trace in which the program state cannot be altered like with rr replay.
5331 // A method is appended to an existing default file with the default phase name. This means that igv_append() must follow
5332 // an earlier igv_print(*) call which sets up the file. This works regardless of any Ideal Graph Visualizer flags set or not.
5333 // Use in debugger (gdb/rr): p igv_append($sp, $fp, $pc).
5334 void igv_append(void* sp, void* fp, void* pc) {
5335   frame fr(sp, fp, pc);
5336   Compile::current()->igv_print_method_to_file(nullptr, true, &fr);
5337 }
5338 
5339 // Same as igv_append(...) above but with a specified phase name.
5340 // Use in debugger (gdb/rr): p igv_append("MyPhase", $sp, $fp, $pc).
5341 void igv_append(const char* phase_name, void* sp, void* fp, void* pc) {
5342   frame fr(sp, fp, pc);
5343   Compile::current()->igv_print_method_to_file(phase_name, true, &fr);
5344 }
5345 
5346 void Compile::igv_print_method_to_file(const char* phase_name, bool append, const frame* fr) {
5347   const char* file_name = "custom_debug.xml";
5348   if (_debug_file_printer == nullptr) {
5349     _debug_file_printer = new IdealGraphPrinter(C, file_name, append);
5350   } else {
5351     _debug_file_printer->update_compiled_method(C->method());
5352   }
5353   tty->print_cr("Method %s to %s", append ? "appended" : "printed", file_name);
5354   _debug_file_printer->print_graph(phase_name, fr);
5355 }
5356 
5357 void Compile::igv_print_method_to_network(const char* phase_name, const frame* fr) {
5358   ResourceMark rm;
5359   GrowableArray<const Node*> empty_list;
5360   igv_print_graph_to_network(phase_name, empty_list, fr);
5361 }
5362 
5363 void Compile::igv_print_graph_to_network(const char* name, GrowableArray<const Node*>& visible_nodes, const frame* fr) {
5364   if (_debug_network_printer == nullptr) {
5365     _debug_network_printer = new IdealGraphPrinter(C);
5366   } else {
5367     _debug_network_printer->update_compiled_method(C->method());
5368   }
5369   tty->print_cr("Method printed over network stream to IGV");
5370   _debug_network_printer->print(name, C->root(), visible_nodes, fr);
5371 }
5372 #endif // !PRODUCT
5373 
5374 Node* Compile::narrow_value(BasicType bt, Node* value, const Type* type, PhaseGVN* phase, bool transform_res) {
5375   if (type != nullptr && phase->type(value)->higher_equal(type)) {
5376     return value;
5377   }
5378   Node* result = nullptr;
5379   if (bt == T_BYTE) {
5380     result = phase->transform(new LShiftINode(value, phase->intcon(24)));
5381     result = new RShiftINode(result, phase->intcon(24));
5382   } else if (bt == T_BOOLEAN) {
5383     result = new AndINode(value, phase->intcon(0xFF));
5384   } else if (bt == T_CHAR) {
5385     result = new AndINode(value,phase->intcon(0xFFFF));
5386   } else {
5387     assert(bt == T_SHORT, "unexpected narrow type");
5388     result = phase->transform(new LShiftINode(value, phase->intcon(16)));
5389     result = new RShiftINode(result, phase->intcon(16));
5390   }
5391   if (transform_res) {
5392     result = phase->transform(result);
5393   }
5394   return result;
5395 }
5396 
5397 void Compile::record_method_not_compilable_oom() {
5398   record_method_not_compilable(CompilationMemoryStatistic::failure_reason_memlimit());
5399 }
5400 
5401 #ifndef PRODUCT
5402 // Collects all the control inputs from nodes on the worklist and from their data dependencies
5403 static void find_candidate_control_inputs(Unique_Node_List& worklist, Unique_Node_List& candidates) {
5404   // Follow non-control edges until we reach CFG nodes
5405   for (uint i = 0; i < worklist.size(); i++) {
5406     const Node* n = worklist.at(i);
5407     for (uint j = 0; j < n->req(); j++) {
5408       Node* in = n->in(j);
5409       if (in == nullptr || in->is_Root()) {
5410         continue;
5411       }
5412       if (in->is_CFG()) {
5413         if (in->is_Call()) {
5414           // The return value of a call is only available if the call did not result in an exception
5415           Node* control_proj_use = in->as_Call()->proj_out(TypeFunc::Control)->unique_out();
5416           if (control_proj_use->is_Catch()) {
5417             Node* fall_through = control_proj_use->as_Catch()->proj_out(CatchProjNode::fall_through_index);
5418             candidates.push(fall_through);
5419             continue;
5420           }
5421         }
5422 
5423         if (in->is_Multi()) {
5424           // We got here by following data inputs so we should only have one control use
5425           // (no IfNode, etc)
5426           assert(!n->is_MultiBranch(), "unexpected node type: %s", n->Name());
5427           candidates.push(in->as_Multi()->proj_out(TypeFunc::Control));
5428         } else {
5429           candidates.push(in);
5430         }
5431       } else {
5432         worklist.push(in);
5433       }
5434     }
5435   }
5436 }
5437 
5438 // Returns the candidate node that is a descendant to all the other candidates
5439 static Node* pick_control(Unique_Node_List& candidates) {
5440   Unique_Node_List worklist;
5441   worklist.copy(candidates);
5442 
5443   // Traverse backwards through the CFG
5444   for (uint i = 0; i < worklist.size(); i++) {
5445     const Node* n = worklist.at(i);
5446     if (n->is_Root()) {
5447       continue;
5448     }
5449     for (uint j = 0; j < n->req(); j++) {
5450       // Skip backedge of loops to avoid cycles
5451       if (n->is_Loop() && j == LoopNode::LoopBackControl) {
5452         continue;
5453       }
5454 
5455       Node* pred = n->in(j);
5456       if (pred != nullptr && pred != n && pred->is_CFG()) {
5457         worklist.push(pred);
5458         // if pred is an ancestor of n, then pred is an ancestor to at least one candidate
5459         candidates.remove(pred);
5460       }
5461     }
5462   }
5463 
5464   assert(candidates.size() == 1, "unexpected control flow");
5465   return candidates.at(0);
5466 }
5467 
5468 // Initialize a parameter input for a debug print call, using a placeholder for jlong and jdouble
5469 static void debug_print_init_parm(Node* call, Node* parm, Node* half, int* pos) {
5470   call->init_req((*pos)++, parm);
5471   const BasicType bt = parm->bottom_type()->basic_type();
5472   if (bt == T_LONG || bt == T_DOUBLE) {
5473     call->init_req((*pos)++, half);
5474   }
5475 }
5476 
5477 Node* Compile::make_debug_print_call(const char* str, address call_addr, PhaseGVN* gvn,
5478                               Node* parm0, Node* parm1,
5479                               Node* parm2, Node* parm3,
5480                               Node* parm4, Node* parm5,
5481                               Node* parm6) const {
5482   Node* str_node = gvn->transform(new ConPNode(TypeRawPtr::make(((address) str))));
5483   const TypeFunc* type = OptoRuntime::debug_print_Type(parm0, parm1, parm2, parm3, parm4, parm5, parm6);
5484   Node* call = new CallLeafNode(type, call_addr, "debug_print", TypeRawPtr::BOTTOM);
5485 
5486   // find the most suitable control input
5487   Unique_Node_List worklist, candidates;
5488   if (parm0 != nullptr) { worklist.push(parm0);
5489   if (parm1 != nullptr) { worklist.push(parm1);
5490   if (parm2 != nullptr) { worklist.push(parm2);
5491   if (parm3 != nullptr) { worklist.push(parm3);
5492   if (parm4 != nullptr) { worklist.push(parm4);
5493   if (parm5 != nullptr) { worklist.push(parm5);
5494   if (parm6 != nullptr) { worklist.push(parm6);
5495   /* close each nested if ===> */  } } } } } } }
5496   find_candidate_control_inputs(worklist, candidates);
5497   Node* control = nullptr;
5498   if (candidates.size() == 0) {
5499     control = C->start()->proj_out(TypeFunc::Control);
5500   } else {
5501     control = pick_control(candidates);
5502   }
5503 
5504   // find all the previous users of the control we picked
5505   GrowableArray<Node*> users_of_control;
5506   for (DUIterator_Fast kmax, i = control->fast_outs(kmax); i < kmax; i++) {
5507     Node* use = control->fast_out(i);
5508     if (use->is_CFG() && use != control) {
5509       users_of_control.push(use);
5510     }
5511   }
5512 
5513   // we do not actually care about IO and memory as it uses neither
5514   call->init_req(TypeFunc::Control,   control);
5515   call->init_req(TypeFunc::I_O,       top());
5516   call->init_req(TypeFunc::Memory,    top());
5517   call->init_req(TypeFunc::FramePtr,  C->start()->proj_out(TypeFunc::FramePtr));
5518   call->init_req(TypeFunc::ReturnAdr, top());
5519 
5520   int pos = TypeFunc::Parms;
5521   call->init_req(pos++, str_node);
5522   if (parm0 != nullptr) { debug_print_init_parm(call, parm0, top(), &pos);
5523   if (parm1 != nullptr) { debug_print_init_parm(call, parm1, top(), &pos);
5524   if (parm2 != nullptr) { debug_print_init_parm(call, parm2, top(), &pos);
5525   if (parm3 != nullptr) { debug_print_init_parm(call, parm3, top(), &pos);
5526   if (parm4 != nullptr) { debug_print_init_parm(call, parm4, top(), &pos);
5527   if (parm5 != nullptr) { debug_print_init_parm(call, parm5, top(), &pos);
5528   if (parm6 != nullptr) { debug_print_init_parm(call, parm6, top(), &pos);
5529   /* close each nested if ===> */  } } } } } } }
5530   assert(call->in(call->req()-1) != nullptr, "must initialize all parms");
5531 
5532   call = gvn->transform(call);
5533   Node* call_control_proj = gvn->transform(new ProjNode(call, TypeFunc::Control));
5534 
5535   // rewire previous users to have the new call as control instead
5536   PhaseIterGVN* igvn = gvn->is_IterGVN();
5537   for (int i = 0; i < users_of_control.length(); i++) {
5538     Node* use = users_of_control.at(i);
5539     for (uint j = 0; j < use->req(); j++) {
5540       if (use->in(j) == control) {
5541         if (igvn != nullptr) {
5542           igvn->replace_input_of(use, j, call_control_proj);
5543         } else {
5544           gvn->hash_delete(use);
5545           use->set_req(j, call_control_proj);
5546           gvn->hash_insert(use);
5547         }
5548       }
5549     }
5550   }
5551 
5552   return call;
5553 }
5554 #endif // !PRODUCT