1 /*
   2  * Copyright (c) 1999, 2025, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "c1/c1_CFGPrinter.hpp"
  26 #include "c1/c1_Canonicalizer.hpp"
  27 #include "c1/c1_Compilation.hpp"
  28 #include "c1/c1_GraphBuilder.hpp"
  29 #include "c1/c1_InstructionPrinter.hpp"
  30 #include "ci/ciCallSite.hpp"
  31 #include "ci/ciField.hpp"
  32 #include "ci/ciFlatArrayKlass.hpp"
  33 #include "ci/ciInlineKlass.hpp"
  34 #include "ci/ciKlass.hpp"
  35 #include "ci/ciMemberName.hpp"
  36 #include "ci/ciSymbols.hpp"
  37 #include "ci/ciUtilities.inline.hpp"
  38 #include "classfile/javaClasses.hpp"
  39 #include "compiler/compilationPolicy.hpp"
  40 #include "compiler/compileBroker.hpp"
  41 #include "compiler/compilerEvent.hpp"
  42 #include "interpreter/bytecode.hpp"
  43 #include "jfr/jfrEvents.hpp"
  44 #include "memory/resourceArea.hpp"
  45 #include "runtime/sharedRuntime.hpp"
  46 #include "utilities/checkedCast.hpp"
  47 #include "utilities/macros.hpp"
  48 #if INCLUDE_JFR
  49 #include "jfr/jfr.hpp"
  50 #endif
  51 
  52 class BlockListBuilder {
  53  private:
  54   Compilation* _compilation;
  55   IRScope*     _scope;
  56 
  57   BlockList    _blocks;                // internal list of all blocks
  58   BlockList*   _bci2block;             // mapping from bci to blocks for GraphBuilder
  59   GrowableArray<BlockList> _bci2block_successors; // Mapping bcis to their blocks successors while we dont have a blockend
  60 
  61   // fields used by mark_loops
  62   ResourceBitMap _active;              // for iteration of control flow graph
  63   ResourceBitMap _visited;             // for iteration of control flow graph
  64   GrowableArray<ResourceBitMap> _loop_map; // caches the information if a block is contained in a loop
  65   int            _next_loop_index;     // next free loop number
  66   int            _next_block_number;   // for reverse postorder numbering of blocks
  67   int            _block_id_start;
  68 
  69   int           bit_number(int block_id) const   { return block_id - _block_id_start; }
  70   // accessors
  71   Compilation*  compilation() const              { return _compilation; }
  72   IRScope*      scope() const                    { return _scope; }
  73   ciMethod*     method() const                   { return scope()->method(); }
  74   XHandlers*    xhandlers() const                { return scope()->xhandlers(); }
  75 
  76   // unified bailout support
  77   void          bailout(const char* msg) const   { compilation()->bailout(msg); }
  78   bool          bailed_out() const               { return compilation()->bailed_out(); }
  79 
  80   // helper functions
  81   BlockBegin* make_block_at(int bci, BlockBegin* predecessor);
  82   void handle_exceptions(BlockBegin* current, int cur_bci);
  83   void handle_jsr(BlockBegin* current, int sr_bci, int next_bci);
  84   void store_one(BlockBegin* current, int local);
  85   void store_two(BlockBegin* current, int local);
  86   void set_entries(int osr_bci);
  87   void set_leaders();
  88 
  89   void make_loop_header(BlockBegin* block);
  90   void mark_loops();
  91   BitMap& mark_loops(BlockBegin* b, bool in_subroutine);
  92 
  93   // debugging
  94 #ifndef PRODUCT
  95   void print();
  96 #endif
  97 
  98   int number_of_successors(BlockBegin* block);
  99   BlockBegin* successor_at(BlockBegin* block, int i);
 100   void add_successor(BlockBegin* block, BlockBegin* sux);
 101   bool is_successor(BlockBegin* block, BlockBegin* sux);
 102 
 103  public:
 104   // creation
 105   BlockListBuilder(Compilation* compilation, IRScope* scope, int osr_bci);
 106 
 107   // accessors for GraphBuilder
 108   BlockList*    bci2block() const                { return _bci2block; }
 109 };
 110 
 111 
 112 // Implementation of BlockListBuilder
 113 
 114 BlockListBuilder::BlockListBuilder(Compilation* compilation, IRScope* scope, int osr_bci)
 115  : _compilation(compilation)
 116  , _scope(scope)
 117  , _blocks(16)
 118  , _bci2block(new BlockList(scope->method()->code_size(), nullptr))
 119  , _bci2block_successors(scope->method()->code_size())
 120  , _active()         // size not known yet
 121  , _visited()        // size not known yet
 122  , _loop_map() // size not known yet
 123  , _next_loop_index(0)
 124  , _next_block_number(0)
 125  , _block_id_start(0)
 126 {
 127   set_entries(osr_bci);
 128   set_leaders();
 129   CHECK_BAILOUT();
 130 
 131   mark_loops();
 132   NOT_PRODUCT(if (PrintInitialBlockList) print());
 133 
 134   // _bci2block still contains blocks with _end == null and > 0 sux in _bci2block_successors.
 135 
 136 #ifndef PRODUCT
 137   if (PrintCFGToFile) {
 138     stringStream title;
 139     title.print("BlockListBuilder ");
 140     scope->method()->print_name(&title);
 141     CFGPrinter::print_cfg(_bci2block, title.freeze(), false, false);
 142   }
 143 #endif
 144 }
 145 
 146 
 147 void BlockListBuilder::set_entries(int osr_bci) {
 148   // generate start blocks
 149   BlockBegin* std_entry = make_block_at(0, nullptr);
 150   if (scope()->caller() == nullptr) {
 151     std_entry->set(BlockBegin::std_entry_flag);
 152   }
 153   if (osr_bci != -1) {
 154     BlockBegin* osr_entry = make_block_at(osr_bci, nullptr);
 155     osr_entry->set(BlockBegin::osr_entry_flag);
 156   }
 157 
 158   // generate exception entry blocks
 159   XHandlers* list = xhandlers();
 160   const int n = list->length();
 161   for (int i = 0; i < n; i++) {
 162     XHandler* h = list->handler_at(i);
 163     BlockBegin* entry = make_block_at(h->handler_bci(), nullptr);
 164     entry->set(BlockBegin::exception_entry_flag);
 165     h->set_entry_block(entry);
 166   }
 167 }
 168 
 169 
 170 BlockBegin* BlockListBuilder::make_block_at(int cur_bci, BlockBegin* predecessor) {
 171   assert(method()->bci_block_start().at(cur_bci), "wrong block starts of MethodLivenessAnalyzer");
 172 
 173   BlockBegin* block = _bci2block->at(cur_bci);
 174   if (block == nullptr) {
 175     block = new BlockBegin(cur_bci);
 176     block->init_stores_to_locals(method()->max_locals());
 177     _bci2block->at_put(cur_bci, block);
 178     _bci2block_successors.at_put_grow(cur_bci, BlockList());
 179     _blocks.append(block);
 180 
 181     assert(predecessor == nullptr || predecessor->bci() < cur_bci, "targets for backward branches must already exist");
 182   }
 183 
 184   if (predecessor != nullptr) {
 185     if (block->is_set(BlockBegin::exception_entry_flag)) {
 186       BAILOUT_("Exception handler can be reached by both normal and exceptional control flow", block);
 187     }
 188 
 189     add_successor(predecessor, block);
 190     block->increment_total_preds();
 191   }
 192 
 193   return block;
 194 }
 195 
 196 
 197 inline void BlockListBuilder::store_one(BlockBegin* current, int local) {
 198   current->stores_to_locals().set_bit(local);
 199 }
 200 inline void BlockListBuilder::store_two(BlockBegin* current, int local) {
 201   store_one(current, local);
 202   store_one(current, local + 1);
 203 }
 204 
 205 
 206 void BlockListBuilder::handle_exceptions(BlockBegin* current, int cur_bci) {
 207   // Draws edges from a block to its exception handlers
 208   XHandlers* list = xhandlers();
 209   const int n = list->length();
 210 
 211   for (int i = 0; i < n; i++) {
 212     XHandler* h = list->handler_at(i);
 213 
 214     if (h->covers(cur_bci)) {
 215       BlockBegin* entry = h->entry_block();
 216       assert(entry != nullptr && entry == _bci2block->at(h->handler_bci()), "entry must be set");
 217       assert(entry->is_set(BlockBegin::exception_entry_flag), "flag must be set");
 218 
 219       // add each exception handler only once
 220       if(!is_successor(current, entry)) {
 221         add_successor(current, entry);
 222         entry->increment_total_preds();
 223       }
 224 
 225       // stop when reaching catchall
 226       if (h->catch_type() == 0) break;
 227     }
 228   }
 229 }
 230 
 231 void BlockListBuilder::handle_jsr(BlockBegin* current, int sr_bci, int next_bci) {
 232   if (next_bci < method()->code_size()) {
 233     // start a new block after jsr-bytecode and link this block into cfg
 234     make_block_at(next_bci, current);
 235   }
 236 
 237   // start a new block at the subroutine entry at mark it with special flag
 238   BlockBegin* sr_block = make_block_at(sr_bci, current);
 239   if (!sr_block->is_set(BlockBegin::subroutine_entry_flag)) {
 240     sr_block->set(BlockBegin::subroutine_entry_flag);
 241   }
 242 }
 243 
 244 
 245 void BlockListBuilder::set_leaders() {
 246   bool has_xhandlers = xhandlers()->has_handlers();
 247   BlockBegin* current = nullptr;
 248 
 249   // The information which bci starts a new block simplifies the analysis
 250   // Without it, backward branches could jump to a bci where no block was created
 251   // during bytecode iteration. This would require the creation of a new block at the
 252   // branch target and a modification of the successor lists.
 253   const BitMap& bci_block_start = method()->bci_block_start();
 254 
 255   int end_bci = method()->code_size();
 256 
 257   ciBytecodeStream s(method());
 258   while (s.next() != ciBytecodeStream::EOBC()) {
 259     int cur_bci = s.cur_bci();
 260 
 261     if (bci_block_start.at(cur_bci)) {
 262       current = make_block_at(cur_bci, current);
 263     }
 264     assert(current != nullptr, "must have current block");
 265 
 266     if (has_xhandlers && GraphBuilder::can_trap(method(), s.cur_bc())) {
 267       handle_exceptions(current, cur_bci);
 268     }
 269 
 270     switch (s.cur_bc()) {
 271       // track stores to local variables for selective creation of phi functions
 272       case Bytecodes::_iinc:     store_one(current, s.get_index()); break;
 273       case Bytecodes::_istore:   store_one(current, s.get_index()); break;
 274       case Bytecodes::_lstore:   store_two(current, s.get_index()); break;
 275       case Bytecodes::_fstore:   store_one(current, s.get_index()); break;
 276       case Bytecodes::_dstore:   store_two(current, s.get_index()); break;
 277       case Bytecodes::_astore:   store_one(current, s.get_index()); break;
 278       case Bytecodes::_istore_0: store_one(current, 0); break;
 279       case Bytecodes::_istore_1: store_one(current, 1); break;
 280       case Bytecodes::_istore_2: store_one(current, 2); break;
 281       case Bytecodes::_istore_3: store_one(current, 3); break;
 282       case Bytecodes::_lstore_0: store_two(current, 0); break;
 283       case Bytecodes::_lstore_1: store_two(current, 1); break;
 284       case Bytecodes::_lstore_2: store_two(current, 2); break;
 285       case Bytecodes::_lstore_3: store_two(current, 3); break;
 286       case Bytecodes::_fstore_0: store_one(current, 0); break;
 287       case Bytecodes::_fstore_1: store_one(current, 1); break;
 288       case Bytecodes::_fstore_2: store_one(current, 2); break;
 289       case Bytecodes::_fstore_3: store_one(current, 3); break;
 290       case Bytecodes::_dstore_0: store_two(current, 0); break;
 291       case Bytecodes::_dstore_1: store_two(current, 1); break;
 292       case Bytecodes::_dstore_2: store_two(current, 2); break;
 293       case Bytecodes::_dstore_3: store_two(current, 3); break;
 294       case Bytecodes::_astore_0: store_one(current, 0); break;
 295       case Bytecodes::_astore_1: store_one(current, 1); break;
 296       case Bytecodes::_astore_2: store_one(current, 2); break;
 297       case Bytecodes::_astore_3: store_one(current, 3); break;
 298 
 299       // track bytecodes that affect the control flow
 300       case Bytecodes::_athrow:  // fall through
 301       case Bytecodes::_ret:     // fall through
 302       case Bytecodes::_ireturn: // fall through
 303       case Bytecodes::_lreturn: // fall through
 304       case Bytecodes::_freturn: // fall through
 305       case Bytecodes::_dreturn: // fall through
 306       case Bytecodes::_areturn: // fall through
 307       case Bytecodes::_return:
 308         current = nullptr;
 309         break;
 310 
 311       case Bytecodes::_ifeq:      // fall through
 312       case Bytecodes::_ifne:      // fall through
 313       case Bytecodes::_iflt:      // fall through
 314       case Bytecodes::_ifge:      // fall through
 315       case Bytecodes::_ifgt:      // fall through
 316       case Bytecodes::_ifle:      // fall through
 317       case Bytecodes::_if_icmpeq: // fall through
 318       case Bytecodes::_if_icmpne: // fall through
 319       case Bytecodes::_if_icmplt: // fall through
 320       case Bytecodes::_if_icmpge: // fall through
 321       case Bytecodes::_if_icmpgt: // fall through
 322       case Bytecodes::_if_icmple: // fall through
 323       case Bytecodes::_if_acmpeq: // fall through
 324       case Bytecodes::_if_acmpne: // fall through
 325       case Bytecodes::_ifnull:    // fall through
 326       case Bytecodes::_ifnonnull:
 327         if (s.next_bci() < end_bci) {
 328           make_block_at(s.next_bci(), current);
 329         }
 330         make_block_at(s.get_dest(), current);
 331         current = nullptr;
 332         break;
 333 
 334       case Bytecodes::_goto:
 335         make_block_at(s.get_dest(), current);
 336         current = nullptr;
 337         break;
 338 
 339       case Bytecodes::_goto_w:
 340         make_block_at(s.get_far_dest(), current);
 341         current = nullptr;
 342         break;
 343 
 344       case Bytecodes::_jsr:
 345         handle_jsr(current, s.get_dest(), s.next_bci());
 346         current = nullptr;
 347         break;
 348 
 349       case Bytecodes::_jsr_w:
 350         handle_jsr(current, s.get_far_dest(), s.next_bci());
 351         current = nullptr;
 352         break;
 353 
 354       case Bytecodes::_tableswitch: {
 355         // set block for each case
 356         Bytecode_tableswitch sw(&s);
 357         int l = sw.length();
 358         for (int i = 0; i < l; i++) {
 359           make_block_at(cur_bci + sw.dest_offset_at(i), current);
 360         }
 361         make_block_at(cur_bci + sw.default_offset(), current);
 362         current = nullptr;
 363         break;
 364       }
 365 
 366       case Bytecodes::_lookupswitch: {
 367         // set block for each case
 368         Bytecode_lookupswitch sw(&s);
 369         int l = sw.number_of_pairs();
 370         for (int i = 0; i < l; i++) {
 371           make_block_at(cur_bci + sw.pair_at(i).offset(), current);
 372         }
 373         make_block_at(cur_bci + sw.default_offset(), current);
 374         current = nullptr;
 375         break;
 376       }
 377 
 378       default:
 379         break;
 380     }
 381   }
 382 }
 383 
 384 
 385 void BlockListBuilder::mark_loops() {
 386   ResourceMark rm;
 387 
 388   const int number_of_blocks = _blocks.length();
 389   _active.initialize(number_of_blocks);
 390   _visited.initialize(number_of_blocks);
 391   _loop_map = GrowableArray<ResourceBitMap>(number_of_blocks, number_of_blocks, ResourceBitMap());
 392   for (int i = 0; i < number_of_blocks; i++) {
 393     _loop_map.at(i).initialize(number_of_blocks);
 394   }
 395   _next_loop_index = 0;
 396   _next_block_number = _blocks.length();
 397 
 398   // The loop detection algorithm works as follows:
 399   // - We maintain the _loop_map, where for each block we have a bitmap indicating which loops contain this block.
 400   // - The CFG is recursively traversed (depth-first) and if we detect a loop, we assign the loop a unique number that is stored
 401   // in the bitmap associated with the loop header block. Until we return back through that loop header the bitmap contains
 402   // only a single bit corresponding to the loop number.
 403   // -  The bit is then propagated for all the blocks in the loop after we exit them (post-order). There could be multiple bits
 404   // of course in case of nested loops.
 405   // -  When we exit the loop header we remove that single bit and assign the real loop state for it.
 406   // -  Now, the tricky part here is how we detect irreducible loops. In the algorithm above the loop state bits
 407   // are propagated to the predecessors. If we encounter an irreducible loop (a loop with multiple heads) we would see
 408   // a node with some loop bit set that would then propagate back and be never cleared because we would
 409   // never go back through the original loop header. Therefore if there are any irreducible loops the bits in the states
 410   // for these loops are going to propagate back to the root.
 411   BlockBegin* start = _bci2block->at(0);
 412   _block_id_start = start->block_id();
 413   BitMap& loop_state = mark_loops(start, false);
 414   if (!loop_state.is_empty()) {
 415     compilation()->set_has_irreducible_loops(true);
 416   }
 417   assert(_next_block_number >= 0, "invalid block numbers");
 418 
 419   // Remove dangling Resource pointers before the ResourceMark goes out-of-scope.
 420   _active.resize(0);
 421   _visited.resize(0);
 422   _loop_map.clear();
 423 }
 424 
 425 void BlockListBuilder::make_loop_header(BlockBegin* block) {
 426   int block_id = block->block_id();
 427   int block_bit = bit_number(block_id);
 428   if (block->is_set(BlockBegin::exception_entry_flag)) {
 429     // exception edges may look like loops but don't mark them as such
 430     // since it screws up block ordering.
 431     return;
 432   }
 433   if (!block->is_set(BlockBegin::parser_loop_header_flag)) {
 434     block->set(BlockBegin::parser_loop_header_flag);
 435 
 436     assert(_loop_map.at(block_bit).is_empty(), "must not be set yet");
 437     assert(0 <= _next_loop_index && _next_loop_index < _loop_map.length(), "_next_loop_index is too large");
 438     _loop_map.at(block_bit).set_bit(_next_loop_index++);
 439   } else {
 440     // block already marked as loop header
 441     assert(_loop_map.at(block_bit).count_one_bits() == 1, "exactly one bit must be set");
 442   }
 443 }
 444 
 445 BitMap& BlockListBuilder::mark_loops(BlockBegin* block, bool in_subroutine) {
 446   int block_id = block->block_id();
 447   int block_bit = bit_number(block_id);
 448   if (_visited.at(block_bit)) {
 449     if (_active.at(block_bit)) {
 450       // reached block via backward branch
 451       make_loop_header(block);
 452     }
 453     // return cached loop information for this block
 454     return _loop_map.at(block_bit);
 455   }
 456 
 457   if (block->is_set(BlockBegin::subroutine_entry_flag)) {
 458     in_subroutine = true;
 459   }
 460 
 461   // set active and visited bits before successors are processed
 462   _visited.set_bit(block_bit);
 463   _active.set_bit(block_bit);
 464 
 465   ResourceMark rm;
 466   ResourceBitMap loop_state(_loop_map.length());
 467   for (int i = number_of_successors(block) - 1; i >= 0; i--) {
 468     BlockBegin* sux = successor_at(block, i);
 469     // recursively process all successors
 470     loop_state.set_union(mark_loops(sux, in_subroutine));
 471   }
 472 
 473   // clear active-bit after all successors are processed
 474   _active.clear_bit(block_bit);
 475 
 476   // reverse-post-order numbering of all blocks
 477   block->set_depth_first_number(_next_block_number);
 478   _next_block_number--;
 479 
 480   if (!loop_state.is_empty() || in_subroutine ) {
 481     // block is contained at least in one loop, so phi functions are necessary
 482     // phi functions are also necessary for all locals stored in a subroutine
 483     scope()->requires_phi_function().set_union(block->stores_to_locals());
 484   }
 485 
 486   if (block->is_set(BlockBegin::parser_loop_header_flag)) {
 487     BitMap& header_loop_state = _loop_map.at(block_bit);
 488     assert(header_loop_state.count_one_bits() == 1, "exactly one bit must be set");
 489     // remove the bit with the loop number for the state (header is outside of the loop)
 490     loop_state.set_difference(header_loop_state);
 491   }
 492 
 493   // cache and return loop information for this block
 494   _loop_map.at(block_bit).set_from(loop_state);
 495   return _loop_map.at(block_bit);
 496 }
 497 
 498 inline int BlockListBuilder::number_of_successors(BlockBegin* block)
 499 {
 500   assert(_bci2block_successors.length() > block->bci(), "sux must exist");
 501   return _bci2block_successors.at(block->bci()).length();
 502 }
 503 
 504 inline BlockBegin* BlockListBuilder::successor_at(BlockBegin* block, int i)
 505 {
 506   assert(_bci2block_successors.length() > block->bci(), "sux must exist");
 507   return _bci2block_successors.at(block->bci()).at(i);
 508 }
 509 
 510 inline void BlockListBuilder::add_successor(BlockBegin* block, BlockBegin* sux)
 511 {
 512   assert(_bci2block_successors.length() > block->bci(), "sux must exist");
 513   _bci2block_successors.at(block->bci()).append(sux);
 514 }
 515 
 516 inline bool BlockListBuilder::is_successor(BlockBegin* block, BlockBegin* sux) {
 517   assert(_bci2block_successors.length() > block->bci(), "sux must exist");
 518   return _bci2block_successors.at(block->bci()).contains(sux);
 519 }
 520 
 521 #ifndef PRODUCT
 522 
 523 static int compare_depth_first(BlockBegin** a, BlockBegin** b) {
 524   return (*a)->depth_first_number() - (*b)->depth_first_number();
 525 }
 526 
 527 void BlockListBuilder::print() {
 528   tty->print("----- initial block list of BlockListBuilder for method ");
 529   method()->print_short_name();
 530   tty->cr();
 531 
 532   // better readability if blocks are sorted in processing order
 533   _blocks.sort(compare_depth_first);
 534 
 535   for (int i = 0; i < _blocks.length(); i++) {
 536     BlockBegin* cur = _blocks.at(i);
 537     tty->print("%4d: B%-4d bci: %-4d  preds: %-4d ", cur->depth_first_number(), cur->block_id(), cur->bci(), cur->total_preds());
 538 
 539     tty->print(cur->is_set(BlockBegin::std_entry_flag)               ? " std" : "    ");
 540     tty->print(cur->is_set(BlockBegin::osr_entry_flag)               ? " osr" : "    ");
 541     tty->print(cur->is_set(BlockBegin::exception_entry_flag)         ? " ex" : "   ");
 542     tty->print(cur->is_set(BlockBegin::subroutine_entry_flag)        ? " sr" : "   ");
 543     tty->print(cur->is_set(BlockBegin::parser_loop_header_flag)      ? " lh" : "   ");
 544 
 545     if (number_of_successors(cur) > 0) {
 546       tty->print("    sux: ");
 547       for (int j = 0; j < number_of_successors(cur); j++) {
 548         BlockBegin* sux = successor_at(cur, j);
 549         tty->print("B%d ", sux->block_id());
 550       }
 551     }
 552     tty->cr();
 553   }
 554 }
 555 
 556 #endif
 557 
 558 
 559 // A simple growable array of Values indexed by ciFields
 560 class FieldBuffer: public CompilationResourceObj {
 561  private:
 562   GrowableArray<Value> _values;
 563 
 564  public:
 565   FieldBuffer() {}
 566 
 567   void kill() {
 568     _values.trunc_to(0);
 569   }
 570 
 571   Value at(ciField* field) {
 572     assert(field->holder()->is_loaded(), "must be a loaded field");
 573     int offset = field->offset_in_bytes();
 574     if (offset < _values.length()) {
 575       return _values.at(offset);
 576     } else {
 577       return nullptr;
 578     }
 579   }
 580 
 581   void at_put(ciField* field, Value value) {
 582     assert(field->holder()->is_loaded(), "must be a loaded field");
 583     int offset = field->offset_in_bytes();
 584     _values.at_put_grow(offset, value, nullptr);
 585   }
 586 
 587 };
 588 
 589 
 590 // MemoryBuffer is fairly simple model of the current state of memory.
 591 // It partitions memory into several pieces.  The first piece is
 592 // generic memory where little is known about the owner of the memory.
 593 // This is conceptually represented by the tuple <O, F, V> which says
 594 // that the field F of object O has value V.  This is flattened so
 595 // that F is represented by the offset of the field and the parallel
 596 // arrays _objects and _values are used for O and V.  Loads of O.F can
 597 // simply use V.  Newly allocated objects are kept in a separate list
 598 // along with a parallel array for each object which represents the
 599 // current value of its fields.  Stores of the default value to fields
 600 // which have never been stored to before are eliminated since they
 601 // are redundant.  Once newly allocated objects are stored into
 602 // another object or they are passed out of the current compile they
 603 // are treated like generic memory.
 604 
 605 class MemoryBuffer: public CompilationResourceObj {
 606  private:
 607   FieldBuffer                 _values;
 608   GrowableArray<Value>        _objects;
 609   GrowableArray<Value>        _newobjects;
 610   GrowableArray<FieldBuffer*> _fields;
 611 
 612  public:
 613   MemoryBuffer() {}
 614 
 615   StoreField* store(StoreField* st) {
 616     if (!EliminateFieldAccess) {
 617       return st;
 618     }
 619 
 620     Value object = st->obj();
 621     Value value = st->value();
 622     ciField* field = st->field();
 623     if (field->holder()->is_loaded()) {
 624       int offset = field->offset_in_bytes();
 625       int index = _newobjects.find(object);
 626       if (index != -1) {
 627         // newly allocated object with no other stores performed on this field
 628         FieldBuffer* buf = _fields.at(index);
 629         if (buf->at(field) == nullptr && is_default_value(value)) {
 630 #ifndef PRODUCT
 631           if (PrintIRDuringConstruction && Verbose) {
 632             tty->print_cr("Eliminated store for object %d:", index);
 633             st->print_line();
 634           }
 635 #endif
 636           return nullptr;
 637         } else {
 638           buf->at_put(field, value);
 639         }
 640       } else {
 641         _objects.at_put_grow(offset, object, nullptr);
 642         _values.at_put(field, value);
 643       }
 644 
 645       store_value(value);
 646     } else {
 647       // if we held onto field names we could alias based on names but
 648       // we don't know what's being stored to so kill it all.
 649       kill();
 650     }
 651     return st;
 652   }
 653 
 654 
 655   // return true if this value correspond to the default value of a field.
 656   bool is_default_value(Value value) {
 657     Constant* con = value->as_Constant();
 658     if (con) {
 659       switch (con->type()->tag()) {
 660         case intTag:    return con->type()->as_IntConstant()->value() == 0;
 661         case longTag:   return con->type()->as_LongConstant()->value() == 0;
 662         case floatTag:  return jint_cast(con->type()->as_FloatConstant()->value()) == 0;
 663         case doubleTag: return jlong_cast(con->type()->as_DoubleConstant()->value()) == jlong_cast(0);
 664         case objectTag: return con->type() == objectNull;
 665         default:  ShouldNotReachHere();
 666       }
 667     }
 668     return false;
 669   }
 670 
 671 
 672   // return either the actual value of a load or the load itself
 673   Value load(LoadField* load) {
 674     if (!EliminateFieldAccess) {
 675       return load;
 676     }
 677 
 678     if (strict_fp_requires_explicit_rounding && load->type()->is_float_kind()) {
 679 #ifdef IA32
 680       if (UseSSE < 2) {
 681         // can't skip load since value might get rounded as a side effect
 682         return load;
 683       }
 684 #else
 685       Unimplemented();
 686 #endif // IA32
 687     }
 688 
 689     ciField* field = load->field();
 690     Value object   = load->obj();
 691     if (field->holder()->is_loaded() && !field->is_volatile()) {
 692       int offset = field->offset_in_bytes();
 693       Value result = nullptr;
 694       int index = _newobjects.find(object);
 695       if (index != -1) {
 696         result = _fields.at(index)->at(field);
 697       } else if (_objects.at_grow(offset, nullptr) == object) {
 698         result = _values.at(field);
 699       }
 700       if (result != nullptr) {
 701 #ifndef PRODUCT
 702         if (PrintIRDuringConstruction && Verbose) {
 703           tty->print_cr("Eliminated load: ");
 704           load->print_line();
 705         }
 706 #endif
 707         assert(result->type()->tag() == load->type()->tag(), "wrong types");
 708         return result;
 709       }
 710     }
 711     return load;
 712   }
 713 
 714   // Record this newly allocated object
 715   void new_instance(NewInstance* object) {
 716     int index = _newobjects.length();
 717     _newobjects.append(object);
 718     if (_fields.at_grow(index, nullptr) == nullptr) {
 719       _fields.at_put(index, new FieldBuffer());
 720     } else {
 721       _fields.at(index)->kill();
 722     }
 723   }
 724 
 725   void store_value(Value value) {
 726     int index = _newobjects.find(value);
 727     if (index != -1) {
 728       // stored a newly allocated object into another object.
 729       // Assume we've lost track of it as separate slice of memory.
 730       // We could do better by keeping track of whether individual
 731       // fields could alias each other.
 732       _newobjects.remove_at(index);
 733       // pull out the field info and store it at the end up the list
 734       // of field info list to be reused later.
 735       _fields.append(_fields.at(index));
 736       _fields.remove_at(index);
 737     }
 738   }
 739 
 740   void kill() {
 741     _newobjects.trunc_to(0);
 742     _objects.trunc_to(0);
 743     _values.kill();
 744   }
 745 };
 746 
 747 
 748 // Implementation of GraphBuilder's ScopeData
 749 
 750 GraphBuilder::ScopeData::ScopeData(ScopeData* parent)
 751   : _parent(parent)
 752   , _bci2block(nullptr)
 753   , _scope(nullptr)
 754   , _has_handler(false)
 755   , _stream(nullptr)
 756   , _work_list(nullptr)
 757   , _caller_stack_size(-1)
 758   , _continuation(nullptr)
 759   , _parsing_jsr(false)
 760   , _jsr_xhandlers(nullptr)
 761   , _num_returns(0)
 762   , _cleanup_block(nullptr)
 763   , _cleanup_return_prev(nullptr)
 764   , _cleanup_state(nullptr)
 765   , _ignore_return(false)
 766 {
 767   if (parent != nullptr) {
 768     _max_inline_size = (intx) ((float) NestedInliningSizeRatio * (float) parent->max_inline_size() / 100.0f);
 769   } else {
 770     _max_inline_size = C1MaxInlineSize;
 771   }
 772   if (_max_inline_size < C1MaxTrivialSize) {
 773     _max_inline_size = C1MaxTrivialSize;
 774   }
 775 }
 776 
 777 
 778 void GraphBuilder::kill_all() {
 779   if (UseLocalValueNumbering) {
 780     vmap()->kill_all();
 781   }
 782   _memory->kill();
 783 }
 784 
 785 
 786 BlockBegin* GraphBuilder::ScopeData::block_at(int bci) {
 787   if (parsing_jsr()) {
 788     // It is necessary to clone all blocks associated with a
 789     // subroutine, including those for exception handlers in the scope
 790     // of the method containing the jsr (because those exception
 791     // handlers may contain ret instructions in some cases).
 792     BlockBegin* block = bci2block()->at(bci);
 793     if (block != nullptr && block == parent()->bci2block()->at(bci)) {
 794       BlockBegin* new_block = new BlockBegin(block->bci());
 795       if (PrintInitialBlockList) {
 796         tty->print_cr("CFG: cloned block %d (bci %d) as block %d for jsr",
 797                       block->block_id(), block->bci(), new_block->block_id());
 798       }
 799       // copy data from cloned blocked
 800       new_block->set_depth_first_number(block->depth_first_number());
 801       if (block->is_set(BlockBegin::parser_loop_header_flag)) new_block->set(BlockBegin::parser_loop_header_flag);
 802       // Preserve certain flags for assertion checking
 803       if (block->is_set(BlockBegin::subroutine_entry_flag)) new_block->set(BlockBegin::subroutine_entry_flag);
 804       if (block->is_set(BlockBegin::exception_entry_flag))  new_block->set(BlockBegin::exception_entry_flag);
 805 
 806       // copy was_visited_flag to allow early detection of bailouts
 807       // if a block that is used in a jsr has already been visited before,
 808       // it is shared between the normal control flow and a subroutine
 809       // BlockBegin::try_merge returns false when the flag is set, this leads
 810       // to a compilation bailout
 811       if (block->is_set(BlockBegin::was_visited_flag))  new_block->set(BlockBegin::was_visited_flag);
 812 
 813       bci2block()->at_put(bci, new_block);
 814       block = new_block;
 815     }
 816     return block;
 817   } else {
 818     return bci2block()->at(bci);
 819   }
 820 }
 821 
 822 
 823 XHandlers* GraphBuilder::ScopeData::xhandlers() const {
 824   if (_jsr_xhandlers == nullptr) {
 825     assert(!parsing_jsr(), "");
 826     return scope()->xhandlers();
 827   }
 828   assert(parsing_jsr(), "");
 829   return _jsr_xhandlers;
 830 }
 831 
 832 
 833 void GraphBuilder::ScopeData::set_scope(IRScope* scope) {
 834   _scope = scope;
 835   bool parent_has_handler = false;
 836   if (parent() != nullptr) {
 837     parent_has_handler = parent()->has_handler();
 838   }
 839   _has_handler = parent_has_handler || scope->xhandlers()->has_handlers();
 840 }
 841 
 842 
 843 void GraphBuilder::ScopeData::set_inline_cleanup_info(BlockBegin* block,
 844                                                       Instruction* return_prev,
 845                                                       ValueStack* return_state) {
 846   _cleanup_block       = block;
 847   _cleanup_return_prev = return_prev;
 848   _cleanup_state       = return_state;
 849 }
 850 
 851 
 852 void GraphBuilder::ScopeData::add_to_work_list(BlockBegin* block) {
 853   if (_work_list == nullptr) {
 854     _work_list = new BlockList();
 855   }
 856 
 857   if (!block->is_set(BlockBegin::is_on_work_list_flag)) {
 858     // Do not start parsing the continuation block while in a
 859     // sub-scope
 860     if (parsing_jsr()) {
 861       if (block == jsr_continuation()) {
 862         return;
 863       }
 864     } else {
 865       if (block == continuation()) {
 866         return;
 867       }
 868     }
 869     block->set(BlockBegin::is_on_work_list_flag);
 870     _work_list->push(block);
 871 
 872     sort_top_into_worklist(_work_list, block);
 873   }
 874 }
 875 
 876 
 877 void GraphBuilder::sort_top_into_worklist(BlockList* worklist, BlockBegin* top) {
 878   assert(worklist->top() == top, "");
 879   // sort block descending into work list
 880   const int dfn = top->depth_first_number();
 881   assert(dfn != -1, "unknown depth first number");
 882   int i = worklist->length()-2;
 883   while (i >= 0) {
 884     BlockBegin* b = worklist->at(i);
 885     if (b->depth_first_number() < dfn) {
 886       worklist->at_put(i+1, b);
 887     } else {
 888       break;
 889     }
 890     i --;
 891   }
 892   if (i >= -1) worklist->at_put(i + 1, top);
 893 }
 894 
 895 
 896 BlockBegin* GraphBuilder::ScopeData::remove_from_work_list() {
 897   if (is_work_list_empty()) {
 898     return nullptr;
 899   }
 900   return _work_list->pop();
 901 }
 902 
 903 
 904 bool GraphBuilder::ScopeData::is_work_list_empty() const {
 905   return (_work_list == nullptr || _work_list->length() == 0);
 906 }
 907 
 908 
 909 void GraphBuilder::ScopeData::setup_jsr_xhandlers() {
 910   assert(parsing_jsr(), "");
 911   // clone all the exception handlers from the scope
 912   XHandlers* handlers = new XHandlers(scope()->xhandlers());
 913   const int n = handlers->length();
 914   for (int i = 0; i < n; i++) {
 915     // The XHandlers need to be adjusted to dispatch to the cloned
 916     // handler block instead of the default one but the synthetic
 917     // unlocker needs to be handled specially.  The synthetic unlocker
 918     // should be left alone since there can be only one and all code
 919     // should dispatch to the same one.
 920     XHandler* h = handlers->handler_at(i);
 921     assert(h->handler_bci() != SynchronizationEntryBCI, "must be real");
 922     h->set_entry_block(block_at(h->handler_bci()));
 923   }
 924   _jsr_xhandlers = handlers;
 925 }
 926 
 927 
 928 int GraphBuilder::ScopeData::num_returns() {
 929   if (parsing_jsr()) {
 930     return parent()->num_returns();
 931   }
 932   return _num_returns;
 933 }
 934 
 935 
 936 void GraphBuilder::ScopeData::incr_num_returns() {
 937   if (parsing_jsr()) {
 938     parent()->incr_num_returns();
 939   } else {
 940     ++_num_returns;
 941   }
 942 }
 943 
 944 
 945 // Implementation of GraphBuilder
 946 
 947 #define INLINE_BAILOUT(msg)        { inline_bailout(msg); return false; }
 948 
 949 
 950 void GraphBuilder::load_constant() {
 951   ciConstant con = stream()->get_constant();
 952   if (con.is_valid()) {
 953     ValueType* t = illegalType;
 954     ValueStack* patch_state = nullptr;
 955     switch (con.basic_type()) {
 956       case T_BOOLEAN: t = new IntConstant   (con.as_boolean()); break;
 957       case T_BYTE   : t = new IntConstant   (con.as_byte   ()); break;
 958       case T_CHAR   : t = new IntConstant   (con.as_char   ()); break;
 959       case T_SHORT  : t = new IntConstant   (con.as_short  ()); break;
 960       case T_INT    : t = new IntConstant   (con.as_int    ()); break;
 961       case T_LONG   : t = new LongConstant  (con.as_long   ()); break;
 962       case T_FLOAT  : t = new FloatConstant (con.as_float  ()); break;
 963       case T_DOUBLE : t = new DoubleConstant(con.as_double ()); break;
 964       case T_ARRAY  : // fall-through
 965       case T_OBJECT : {
 966         ciObject* obj = con.as_object();
 967         if (!obj->is_loaded() || (PatchALot && !stream()->is_string_constant())) {
 968           // A Class, MethodType, MethodHandle, Dynamic, or String.
 969           patch_state = copy_state_before();
 970           t = new ObjectConstant(obj);
 971         } else {
 972           // Might be a Class, MethodType, MethodHandle, or Dynamic constant
 973           // result, which might turn out to be an array.
 974           if (obj->is_null_object()) {
 975             t = objectNull;
 976           } else if (obj->is_array()) {
 977             t = new ArrayConstant(obj->as_array());
 978           } else {
 979             t = new InstanceConstant(obj->as_instance());
 980           }
 981         }
 982         break;
 983       }
 984       default: ShouldNotReachHere();
 985     }
 986     Value x;
 987     if (patch_state != nullptr) {
 988       // Arbitrary memory effects from running BSM or class loading (using custom loader) during linkage.
 989       bool kills_memory = stream()->is_dynamic_constant() ||
 990                           (!stream()->is_string_constant() && !method()->holder()->has_trusted_loader());
 991       x = new Constant(t, patch_state, kills_memory);
 992     } else {
 993       x = new Constant(t);
 994     }
 995 
 996     // Unbox the value at runtime, if needed.
 997     // ConstantDynamic entry can be of a primitive type, but it is cached in boxed form.
 998     if (patch_state != nullptr) {
 999       int cp_index = stream()->get_constant_pool_index();
1000       BasicType type = stream()->get_basic_type_for_constant_at(cp_index);
1001       if (is_java_primitive(type)) {
1002         ciInstanceKlass* box_klass = ciEnv::current()->get_box_klass_for_primitive_type(type);
1003         assert(box_klass->is_loaded(), "sanity");
1004         int offset = java_lang_boxing_object::value_offset(type);
1005         ciField* value_field = box_klass->get_field_by_offset(offset, false /*is_static*/);
1006         x = new LoadField(append(x), offset, value_field, false /*is_static*/, patch_state, false /*needs_patching*/);
1007         t = as_ValueType(type);
1008       } else {
1009         assert(is_reference_type(type), "not a reference: %s", type2name(type));
1010       }
1011     }
1012 
1013     push(t, append(x));
1014   } else {
1015     BAILOUT("could not resolve a constant");
1016   }
1017 }
1018 
1019 
1020 void GraphBuilder::load_local(ValueType* type, int index) {
1021   Value x = state()->local_at(index);
1022   assert(x != nullptr && !x->type()->is_illegal(), "access of illegal local variable");
1023   push(type, x);
1024 }
1025 
1026 
1027 void GraphBuilder::store_local(ValueType* type, int index) {
1028   Value x = pop(type);
1029   store_local(state(), x, index);
1030 }
1031 
1032 
1033 void GraphBuilder::store_local(ValueStack* state, Value x, int index) {
1034   if (parsing_jsr()) {
1035     // We need to do additional tracking of the location of the return
1036     // address for jsrs since we don't handle arbitrary jsr/ret
1037     // constructs. Here we are figuring out in which circumstances we
1038     // need to bail out.
1039     if (x->type()->is_address()) {
1040       scope_data()->set_jsr_return_address_local(index);
1041 
1042       // Also check parent jsrs (if any) at this time to see whether
1043       // they are using this local. We don't handle skipping over a
1044       // ret.
1045       for (ScopeData* cur_scope_data = scope_data()->parent();
1046            cur_scope_data != nullptr && cur_scope_data->parsing_jsr() && cur_scope_data->scope() == scope();
1047            cur_scope_data = cur_scope_data->parent()) {
1048         if (cur_scope_data->jsr_return_address_local() == index) {
1049           BAILOUT("subroutine overwrites return address from previous subroutine");
1050         }
1051       }
1052     } else if (index == scope_data()->jsr_return_address_local()) {
1053       scope_data()->set_jsr_return_address_local(-1);
1054     }
1055   }
1056 
1057   state->store_local(index, round_fp(x));
1058 }
1059 
1060 
1061 void GraphBuilder::load_indexed(BasicType type) {
1062   // In case of in block code motion in range check elimination
1063   ValueStack* state_before = nullptr;
1064   int array_idx = state()->stack_size() - 2;
1065   if (type == T_OBJECT && state()->stack_at(array_idx)->maybe_flat_array()) {
1066     // Save the entire state and re-execute on deopt when accessing flat arrays
1067     state_before = copy_state_before();
1068     state_before->set_should_reexecute(true);
1069   } else {
1070     state_before = copy_state_indexed_access();
1071   }
1072   compilation()->set_has_access_indexed(true);
1073   Value index = ipop();
1074   Value array = apop();
1075   Value length = nullptr;
1076   if (CSEArrayLength ||
1077       (array->as_Constant() != nullptr) ||
1078       (array->as_AccessField() && array->as_AccessField()->field()->is_constant()) ||
1079       (array->as_NewArray() && array->as_NewArray()->length() && array->as_NewArray()->length()->type()->is_constant()) ||
1080       (array->as_NewMultiArray() && array->as_NewMultiArray()->dims()->at(0)->type()->is_constant())) {
1081     length = append(new ArrayLength(array, state_before));
1082   }
1083 
1084   bool need_membar = false;
1085   LoadIndexed* load_indexed = nullptr;
1086   Instruction* result = nullptr;
1087   if (array->is_loaded_flat_array()) {
1088     // TODO 8350865 This is currently dead code
1089     ciType* array_type = array->declared_type();
1090     ciInlineKlass* elem_klass = array_type->as_flat_array_klass()->element_klass()->as_inline_klass();
1091 
1092     bool can_delay_access = false;
1093     ciBytecodeStream s(method());
1094     s.force_bci(bci());
1095     s.next();
1096     if (s.cur_bc() == Bytecodes::_getfield) {
1097       bool will_link;
1098       ciField* next_field = s.get_field(will_link);
1099       bool next_needs_patching = !next_field->holder()->is_initialized() ||
1100                                  !next_field->will_link(method(), Bytecodes::_getfield) ||
1101                                  PatchALot;
1102       can_delay_access = C1UseDelayedFlattenedFieldReads && !next_needs_patching;
1103     }
1104     if (can_delay_access) {
1105       // potentially optimizable array access, storing information for delayed decision
1106       LoadIndexed* li = new LoadIndexed(array, index, length, type, state_before);
1107       DelayedLoadIndexed* dli = new DelayedLoadIndexed(li, state_before);
1108       li->set_delayed(dli);
1109       set_pending_load_indexed(dli);
1110       return; // Nothing else to do for now
1111     } else {
1112       if (elem_klass->is_empty()) {
1113         // No need to create a new instance, the default instance will be used instead
1114         load_indexed = new LoadIndexed(array, index, length, type, state_before);
1115         apush(append(load_indexed));
1116       } else {
1117         NewInstance* new_instance = new NewInstance(elem_klass, state_before, false, true);
1118         _memory->new_instance(new_instance);
1119         apush(append_split(new_instance));
1120         load_indexed = new LoadIndexed(array, index, length, type, state_before);
1121         load_indexed->set_vt(new_instance);
1122         // The LoadIndexed node will initialise this instance by copying from
1123         // the flat field.  Ensure these stores are visible before any
1124         // subsequent store that publishes this reference.
1125         need_membar = true;
1126       }
1127     }
1128   } else {
1129     load_indexed = new LoadIndexed(array, index, length, type, state_before);
1130     if (profile_array_accesses() && is_reference_type(type)) {
1131       compilation()->set_would_profile(true);
1132       load_indexed->set_should_profile(true);
1133       load_indexed->set_profiled_method(method());
1134       load_indexed->set_profiled_bci(bci());
1135     }
1136   }
1137   result = append(load_indexed);
1138   if (need_membar) {
1139     append(new MemBar(lir_membar_storestore));
1140   }
1141   assert(!load_indexed->should_profile() || load_indexed == result, "should not be optimized out");
1142   if (!array->is_loaded_flat_array()) {
1143     push(as_ValueType(type), result);
1144   }
1145 }
1146 
1147 
1148 void GraphBuilder::store_indexed(BasicType type) {
1149   // In case of in block code motion in range check elimination
1150   ValueStack* state_before = nullptr;
1151   int array_idx = state()->stack_size() - 3;
1152   if (type == T_OBJECT && state()->stack_at(array_idx)->maybe_flat_array()) {
1153     // Save the entire state and re-execute on deopt when accessing flat arrays
1154     state_before = copy_state_before();
1155     state_before->set_should_reexecute(true);
1156   } else {
1157     state_before = copy_state_indexed_access();
1158   }
1159   compilation()->set_has_access_indexed(true);
1160   Value value = pop(as_ValueType(type));
1161   Value index = ipop();
1162   Value array = apop();
1163   Value length = nullptr;
1164   if (CSEArrayLength ||
1165       (array->as_Constant() != nullptr) ||
1166       (array->as_AccessField() && array->as_AccessField()->field()->is_constant()) ||
1167       (array->as_NewArray() && array->as_NewArray()->length() && array->as_NewArray()->length()->type()->is_constant()) ||
1168       (array->as_NewMultiArray() && array->as_NewMultiArray()->dims()->at(0)->type()->is_constant())) {
1169     length = append(new ArrayLength(array, state_before));
1170   }
1171   ciType* array_type = array->declared_type();
1172   bool check_boolean = false;
1173   if (array_type != nullptr) {
1174     if (array_type->is_loaded() &&
1175       array_type->as_array_klass()->element_type()->basic_type() == T_BOOLEAN) {
1176       assert(type == T_BYTE, "boolean store uses bastore");
1177       Value mask = append(new Constant(new IntConstant(1)));
1178       value = append(new LogicOp(Bytecodes::_iand, value, mask));
1179     }
1180   } else if (type == T_BYTE) {
1181     check_boolean = true;
1182   }
1183 
1184   StoreIndexed* store_indexed = new StoreIndexed(array, index, length, type, value, state_before, check_boolean);
1185   if (profile_array_accesses() && is_reference_type(type) && !array->is_loaded_flat_array()) {
1186     compilation()->set_would_profile(true);
1187     store_indexed->set_should_profile(true);
1188     store_indexed->set_profiled_method(method());
1189     store_indexed->set_profiled_bci(bci());
1190   }
1191   Instruction* result = append(store_indexed);
1192   assert(!store_indexed->should_profile() || store_indexed == result, "should not be optimized out");
1193   _memory->store_value(value);
1194 }
1195 
1196 void GraphBuilder::stack_op(Bytecodes::Code code) {
1197   switch (code) {
1198     case Bytecodes::_pop:
1199       { Value w = state()->raw_pop();
1200       }
1201       break;
1202     case Bytecodes::_pop2:
1203       { Value w1 = state()->raw_pop();
1204         Value w2 = state()->raw_pop();
1205       }
1206       break;
1207     case Bytecodes::_dup:
1208       { Value w = state()->raw_pop();
1209         state()->raw_push(w);
1210         state()->raw_push(w);
1211       }
1212       break;
1213     case Bytecodes::_dup_x1:
1214       { Value w1 = state()->raw_pop();
1215         Value w2 = state()->raw_pop();
1216         state()->raw_push(w1);
1217         state()->raw_push(w2);
1218         state()->raw_push(w1);
1219       }
1220       break;
1221     case Bytecodes::_dup_x2:
1222       { Value w1 = state()->raw_pop();
1223         Value w2 = state()->raw_pop();
1224         Value w3 = state()->raw_pop();
1225         state()->raw_push(w1);
1226         state()->raw_push(w3);
1227         state()->raw_push(w2);
1228         state()->raw_push(w1);
1229       }
1230       break;
1231     case Bytecodes::_dup2:
1232       { Value w1 = state()->raw_pop();
1233         Value w2 = state()->raw_pop();
1234         state()->raw_push(w2);
1235         state()->raw_push(w1);
1236         state()->raw_push(w2);
1237         state()->raw_push(w1);
1238       }
1239       break;
1240     case Bytecodes::_dup2_x1:
1241       { Value w1 = state()->raw_pop();
1242         Value w2 = state()->raw_pop();
1243         Value w3 = state()->raw_pop();
1244         state()->raw_push(w2);
1245         state()->raw_push(w1);
1246         state()->raw_push(w3);
1247         state()->raw_push(w2);
1248         state()->raw_push(w1);
1249       }
1250       break;
1251     case Bytecodes::_dup2_x2:
1252       { Value w1 = state()->raw_pop();
1253         Value w2 = state()->raw_pop();
1254         Value w3 = state()->raw_pop();
1255         Value w4 = state()->raw_pop();
1256         state()->raw_push(w2);
1257         state()->raw_push(w1);
1258         state()->raw_push(w4);
1259         state()->raw_push(w3);
1260         state()->raw_push(w2);
1261         state()->raw_push(w1);
1262       }
1263       break;
1264     case Bytecodes::_swap:
1265       { Value w1 = state()->raw_pop();
1266         Value w2 = state()->raw_pop();
1267         state()->raw_push(w1);
1268         state()->raw_push(w2);
1269       }
1270       break;
1271     default:
1272       ShouldNotReachHere();
1273       break;
1274   }
1275 }
1276 
1277 
1278 void GraphBuilder::arithmetic_op(ValueType* type, Bytecodes::Code code, ValueStack* state_before) {
1279   Value y = pop(type);
1280   Value x = pop(type);
1281   Value res = new ArithmeticOp(code, x, y, state_before);
1282   // Note: currently single-precision floating-point rounding on Intel is handled at the LIRGenerator level
1283   res = append(res);
1284   res = round_fp(res);
1285   push(type, res);
1286 }
1287 
1288 
1289 void GraphBuilder::negate_op(ValueType* type) {
1290   push(type, append(new NegateOp(pop(type))));
1291 }
1292 
1293 
1294 void GraphBuilder::shift_op(ValueType* type, Bytecodes::Code code) {
1295   Value s = ipop();
1296   Value x = pop(type);
1297   // try to simplify
1298   // Note: This code should go into the canonicalizer as soon as it can
1299   //       can handle canonicalized forms that contain more than one node.
1300   if (CanonicalizeNodes && code == Bytecodes::_iushr) {
1301     // pattern: x >>> s
1302     IntConstant* s1 = s->type()->as_IntConstant();
1303     if (s1 != nullptr) {
1304       // pattern: x >>> s1, with s1 constant
1305       ShiftOp* l = x->as_ShiftOp();
1306       if (l != nullptr && l->op() == Bytecodes::_ishl) {
1307         // pattern: (a << b) >>> s1
1308         IntConstant* s0 = l->y()->type()->as_IntConstant();
1309         if (s0 != nullptr) {
1310           // pattern: (a << s0) >>> s1
1311           const int s0c = s0->value() & 0x1F; // only the low 5 bits are significant for shifts
1312           const int s1c = s1->value() & 0x1F; // only the low 5 bits are significant for shifts
1313           if (s0c == s1c) {
1314             if (s0c == 0) {
1315               // pattern: (a << 0) >>> 0 => simplify to: a
1316               ipush(l->x());
1317             } else {
1318               // pattern: (a << s0c) >>> s0c => simplify to: a & m, with m constant
1319               assert(0 < s0c && s0c < BitsPerInt, "adjust code below to handle corner cases");
1320               const int m = checked_cast<int>(right_n_bits(BitsPerInt - s0c));
1321               Value s = append(new Constant(new IntConstant(m)));
1322               ipush(append(new LogicOp(Bytecodes::_iand, l->x(), s)));
1323             }
1324             return;
1325           }
1326         }
1327       }
1328     }
1329   }
1330   // could not simplify
1331   push(type, append(new ShiftOp(code, x, s)));
1332 }
1333 
1334 
1335 void GraphBuilder::logic_op(ValueType* type, Bytecodes::Code code) {
1336   Value y = pop(type);
1337   Value x = pop(type);
1338   push(type, append(new LogicOp(code, x, y)));
1339 }
1340 
1341 
1342 void GraphBuilder::compare_op(ValueType* type, Bytecodes::Code code) {
1343   ValueStack* state_before = copy_state_before();
1344   Value y = pop(type);
1345   Value x = pop(type);
1346   ipush(append(new CompareOp(code, x, y, state_before)));
1347 }
1348 
1349 
1350 void GraphBuilder::convert(Bytecodes::Code op, BasicType from, BasicType to) {
1351   push(as_ValueType(to), append(new Convert(op, pop(as_ValueType(from)), as_ValueType(to))));
1352 }
1353 
1354 
1355 void GraphBuilder::increment() {
1356   int index = stream()->get_index();
1357   int delta = stream()->is_wide() ? (signed short)Bytes::get_Java_u2(stream()->cur_bcp() + 4) : (signed char)(stream()->cur_bcp()[2]);
1358   load_local(intType, index);
1359   ipush(append(new Constant(new IntConstant(delta))));
1360   arithmetic_op(intType, Bytecodes::_iadd);
1361   store_local(intType, index);
1362 }
1363 
1364 
1365 void GraphBuilder::_goto(int from_bci, int to_bci) {
1366   Goto *x = new Goto(block_at(to_bci), to_bci <= from_bci);
1367   if (is_profiling()) {
1368     compilation()->set_would_profile(true);
1369     x->set_profiled_bci(bci());
1370     if (profile_branches()) {
1371       x->set_profiled_method(method());
1372       x->set_should_profile(true);
1373     }
1374   }
1375   append(x);
1376 }
1377 
1378 
1379 void GraphBuilder::if_node(Value x, If::Condition cond, Value y, ValueStack* state_before) {
1380   BlockBegin* tsux = block_at(stream()->get_dest());
1381   BlockBegin* fsux = block_at(stream()->next_bci());
1382   bool is_bb = tsux->bci() < stream()->cur_bci() || fsux->bci() < stream()->cur_bci();
1383 
1384   bool subst_check = false;
1385   if (EnableValhalla && (stream()->cur_bc() == Bytecodes::_if_acmpeq || stream()->cur_bc() == Bytecodes::_if_acmpne)) {
1386     ValueType* left_vt = x->type();
1387     ValueType* right_vt = y->type();
1388     if (left_vt->is_object()) {
1389       assert(right_vt->is_object(), "must be");
1390       ciKlass* left_klass = x->as_loaded_klass_or_null();
1391       ciKlass* right_klass = y->as_loaded_klass_or_null();
1392 
1393       if (left_klass == nullptr || right_klass == nullptr) {
1394         // The klass is still unloaded, or came from a Phi node. Go slow case;
1395         subst_check = true;
1396       } else if (left_klass->can_be_inline_klass() || right_klass->can_be_inline_klass()) {
1397         // Either operand may be a value object, but we're not sure. Go slow case;
1398         subst_check = true;
1399       } else {
1400         // No need to do substitutability check
1401       }
1402     }
1403   }
1404   if ((stream()->cur_bc() == Bytecodes::_if_acmpeq || stream()->cur_bc() == Bytecodes::_if_acmpne) &&
1405       is_profiling() && profile_branches()) {
1406     compilation()->set_would_profile(true);
1407     append(new ProfileACmpTypes(method(), bci(), x, y));
1408   }
1409 
1410   // In case of loop invariant code motion or predicate insertion
1411   // before the body of a loop the state is needed
1412   Instruction *i = append(new If(x, cond, false, y, tsux, fsux, (is_bb || compilation()->is_optimistic() || subst_check) ? state_before : nullptr, is_bb, subst_check));
1413 
1414   assert(i->as_Goto() == nullptr ||
1415          (i->as_Goto()->sux_at(0) == tsux  && i->as_Goto()->is_safepoint() == (tsux->bci() < stream()->cur_bci())) ||
1416          (i->as_Goto()->sux_at(0) == fsux  && i->as_Goto()->is_safepoint() == (fsux->bci() < stream()->cur_bci())),
1417          "safepoint state of Goto returned by canonicalizer incorrect");
1418 
1419   if (is_profiling()) {
1420     If* if_node = i->as_If();
1421     if (if_node != nullptr) {
1422       // Note that we'd collect profile data in this method if we wanted it.
1423       compilation()->set_would_profile(true);
1424       // At level 2 we need the proper bci to count backedges
1425       if_node->set_profiled_bci(bci());
1426       if (profile_branches()) {
1427         // Successors can be rotated by the canonicalizer, check for this case.
1428         if_node->set_profiled_method(method());
1429         if_node->set_should_profile(true);
1430         if (if_node->tsux() == fsux) {
1431           if_node->set_swapped(true);
1432         }
1433       }
1434       return;
1435     }
1436 
1437     // Check if this If was reduced to Goto.
1438     Goto *goto_node = i->as_Goto();
1439     if (goto_node != nullptr) {
1440       compilation()->set_would_profile(true);
1441       goto_node->set_profiled_bci(bci());
1442       if (profile_branches()) {
1443         goto_node->set_profiled_method(method());
1444         goto_node->set_should_profile(true);
1445         // Find out which successor is used.
1446         if (goto_node->default_sux() == tsux) {
1447           goto_node->set_direction(Goto::taken);
1448         } else if (goto_node->default_sux() == fsux) {
1449           goto_node->set_direction(Goto::not_taken);
1450         } else {
1451           ShouldNotReachHere();
1452         }
1453       }
1454       return;
1455     }
1456   }
1457 }
1458 
1459 
1460 void GraphBuilder::if_zero(ValueType* type, If::Condition cond) {
1461   Value y = append(new Constant(intZero));
1462   ValueStack* state_before = copy_state_before();
1463   Value x = ipop();
1464   if_node(x, cond, y, state_before);
1465 }
1466 
1467 
1468 void GraphBuilder::if_null(ValueType* type, If::Condition cond) {
1469   Value y = append(new Constant(objectNull));
1470   ValueStack* state_before = copy_state_before();
1471   Value x = apop();
1472   if_node(x, cond, y, state_before);
1473 }
1474 
1475 
1476 void GraphBuilder::if_same(ValueType* type, If::Condition cond) {
1477   ValueStack* state_before = copy_state_before();
1478   Value y = pop(type);
1479   Value x = pop(type);
1480   if_node(x, cond, y, state_before);
1481 }
1482 
1483 
1484 void GraphBuilder::jsr(int dest) {
1485   // We only handle well-formed jsrs (those which are "block-structured").
1486   // If the bytecodes are strange (jumping out of a jsr block) then we
1487   // might end up trying to re-parse a block containing a jsr which
1488   // has already been activated. Watch for this case and bail out.
1489   if (next_bci() >= method()->code_size()) {
1490     // This can happen if the subroutine does not terminate with a ret,
1491     // effectively turning the jsr into a goto.
1492     BAILOUT("too-complicated jsr/ret structure");
1493   }
1494   for (ScopeData* cur_scope_data = scope_data();
1495        cur_scope_data != nullptr && cur_scope_data->parsing_jsr() && cur_scope_data->scope() == scope();
1496        cur_scope_data = cur_scope_data->parent()) {
1497     if (cur_scope_data->jsr_entry_bci() == dest) {
1498       BAILOUT("too-complicated jsr/ret structure");
1499     }
1500   }
1501 
1502   push(addressType, append(new Constant(new AddressConstant(next_bci()))));
1503   if (!try_inline_jsr(dest)) {
1504     return; // bailed out while parsing and inlining subroutine
1505   }
1506 }
1507 
1508 
1509 void GraphBuilder::ret(int local_index) {
1510   if (!parsing_jsr()) BAILOUT("ret encountered while not parsing subroutine");
1511 
1512   if (local_index != scope_data()->jsr_return_address_local()) {
1513     BAILOUT("can not handle complicated jsr/ret constructs");
1514   }
1515 
1516   // Rets simply become (NON-SAFEPOINT) gotos to the jsr continuation
1517   append(new Goto(scope_data()->jsr_continuation(), false));
1518 }
1519 
1520 
1521 void GraphBuilder::table_switch() {
1522   Bytecode_tableswitch sw(stream());
1523   const int l = sw.length();
1524   if (CanonicalizeNodes && l == 1 && compilation()->env()->comp_level() != CompLevel_full_profile) {
1525     // total of 2 successors => use If instead of switch
1526     // Note: This code should go into the canonicalizer as soon as it can
1527     //       can handle canonicalized forms that contain more than one node.
1528     Value key = append(new Constant(new IntConstant(sw.low_key())));
1529     BlockBegin* tsux = block_at(bci() + sw.dest_offset_at(0));
1530     BlockBegin* fsux = block_at(bci() + sw.default_offset());
1531     bool is_bb = tsux->bci() < bci() || fsux->bci() < bci();
1532     // In case of loop invariant code motion or predicate insertion
1533     // before the body of a loop the state is needed
1534     ValueStack* state_before = copy_state_if_bb(is_bb);
1535     append(new If(ipop(), If::eql, true, key, tsux, fsux, state_before, is_bb));
1536   } else {
1537     // collect successors
1538     BlockList* sux = new BlockList(l + 1, nullptr);
1539     int i;
1540     bool has_bb = false;
1541     for (i = 0; i < l; i++) {
1542       sux->at_put(i, block_at(bci() + sw.dest_offset_at(i)));
1543       if (sw.dest_offset_at(i) < 0) has_bb = true;
1544     }
1545     // add default successor
1546     if (sw.default_offset() < 0) has_bb = true;
1547     sux->at_put(i, block_at(bci() + sw.default_offset()));
1548     // In case of loop invariant code motion or predicate insertion
1549     // before the body of a loop the state is needed
1550     ValueStack* state_before = copy_state_if_bb(has_bb);
1551     Instruction* res = append(new TableSwitch(ipop(), sux, sw.low_key(), state_before, has_bb));
1552 #ifdef ASSERT
1553     if (res->as_Goto()) {
1554       for (i = 0; i < l; i++) {
1555         if (sux->at(i) == res->as_Goto()->sux_at(0)) {
1556           assert(res->as_Goto()->is_safepoint() == (sw.dest_offset_at(i) < 0), "safepoint state of Goto returned by canonicalizer incorrect");
1557         }
1558       }
1559     }
1560 #endif
1561   }
1562 }
1563 
1564 
1565 void GraphBuilder::lookup_switch() {
1566   Bytecode_lookupswitch sw(stream());
1567   const int l = sw.number_of_pairs();
1568   if (CanonicalizeNodes && l == 1 && compilation()->env()->comp_level() != CompLevel_full_profile) {
1569     // total of 2 successors => use If instead of switch
1570     // Note: This code should go into the canonicalizer as soon as it can
1571     //       can handle canonicalized forms that contain more than one node.
1572     // simplify to If
1573     LookupswitchPair pair = sw.pair_at(0);
1574     Value key = append(new Constant(new IntConstant(pair.match())));
1575     BlockBegin* tsux = block_at(bci() + pair.offset());
1576     BlockBegin* fsux = block_at(bci() + sw.default_offset());
1577     bool is_bb = tsux->bci() < bci() || fsux->bci() < bci();
1578     // In case of loop invariant code motion or predicate insertion
1579     // before the body of a loop the state is needed
1580     ValueStack* state_before = copy_state_if_bb(is_bb);;
1581     append(new If(ipop(), If::eql, true, key, tsux, fsux, state_before, is_bb));
1582   } else {
1583     // collect successors & keys
1584     BlockList* sux = new BlockList(l + 1, nullptr);
1585     intArray* keys = new intArray(l, l, 0);
1586     int i;
1587     bool has_bb = false;
1588     for (i = 0; i < l; i++) {
1589       LookupswitchPair pair = sw.pair_at(i);
1590       if (pair.offset() < 0) has_bb = true;
1591       sux->at_put(i, block_at(bci() + pair.offset()));
1592       keys->at_put(i, pair.match());
1593     }
1594     // add default successor
1595     if (sw.default_offset() < 0) has_bb = true;
1596     sux->at_put(i, block_at(bci() + sw.default_offset()));
1597     // In case of loop invariant code motion or predicate insertion
1598     // before the body of a loop the state is needed
1599     ValueStack* state_before = copy_state_if_bb(has_bb);
1600     Instruction* res = append(new LookupSwitch(ipop(), sux, keys, state_before, has_bb));
1601 #ifdef ASSERT
1602     if (res->as_Goto()) {
1603       for (i = 0; i < l; i++) {
1604         if (sux->at(i) == res->as_Goto()->sux_at(0)) {
1605           assert(res->as_Goto()->is_safepoint() == (sw.pair_at(i).offset() < 0), "safepoint state of Goto returned by canonicalizer incorrect");
1606         }
1607       }
1608     }
1609 #endif
1610   }
1611 }
1612 
1613 void GraphBuilder::call_register_finalizer() {
1614   // If the receiver requires finalization then emit code to perform
1615   // the registration on return.
1616 
1617   // Gather some type information about the receiver
1618   Value receiver = state()->local_at(0);
1619   assert(receiver != nullptr, "must have a receiver");
1620   ciType* declared_type = receiver->declared_type();
1621   ciType* exact_type = receiver->exact_type();
1622   if (exact_type == nullptr &&
1623       receiver->as_Local() &&
1624       receiver->as_Local()->java_index() == 0) {
1625     ciInstanceKlass* ik = compilation()->method()->holder();
1626     if (ik->is_final()) {
1627       exact_type = ik;
1628     } else if (UseCHA && !(ik->has_subklass() || ik->is_interface())) {
1629       // test class is leaf class
1630       compilation()->dependency_recorder()->assert_leaf_type(ik);
1631       exact_type = ik;
1632     } else {
1633       declared_type = ik;
1634     }
1635   }
1636 
1637   // see if we know statically that registration isn't required
1638   bool needs_check = true;
1639   if (exact_type != nullptr) {
1640     needs_check = exact_type->as_instance_klass()->has_finalizer();
1641   } else if (declared_type != nullptr) {
1642     ciInstanceKlass* ik = declared_type->as_instance_klass();
1643     if (!Dependencies::has_finalizable_subclass(ik)) {
1644       compilation()->dependency_recorder()->assert_has_no_finalizable_subclasses(ik);
1645       needs_check = false;
1646     }
1647   }
1648 
1649   if (needs_check) {
1650     // Perform the registration of finalizable objects.
1651     ValueStack* state_before = copy_state_for_exception();
1652     load_local(objectType, 0);
1653     append_split(new Intrinsic(voidType, vmIntrinsics::_Object_init,
1654                                state()->pop_arguments(1),
1655                                true, state_before, true));
1656   }
1657 }
1658 
1659 
1660 void GraphBuilder::method_return(Value x, bool ignore_return) {
1661   if (method()->intrinsic_id() == vmIntrinsics::_Object_init) {
1662     call_register_finalizer();
1663   }
1664 
1665   // The conditions for a memory barrier are described in Parse::do_exits().
1666   bool need_mem_bar = false;
1667   if (method()->is_object_constructor() &&
1668        (scope()->wrote_final() || scope()->wrote_stable() ||
1669          (AlwaysSafeConstructors && scope()->wrote_fields()) ||
1670          (support_IRIW_for_not_multiple_copy_atomic_cpu && scope()->wrote_volatile()))) {
1671     need_mem_bar = true;
1672   }
1673 
1674   BasicType bt = method()->return_type()->basic_type();
1675   switch (bt) {
1676     case T_BYTE:
1677     {
1678       Value shift = append(new Constant(new IntConstant(24)));
1679       x = append(new ShiftOp(Bytecodes::_ishl, x, shift));
1680       x = append(new ShiftOp(Bytecodes::_ishr, x, shift));
1681       break;
1682     }
1683     case T_SHORT:
1684     {
1685       Value shift = append(new Constant(new IntConstant(16)));
1686       x = append(new ShiftOp(Bytecodes::_ishl, x, shift));
1687       x = append(new ShiftOp(Bytecodes::_ishr, x, shift));
1688       break;
1689     }
1690     case T_CHAR:
1691     {
1692       Value mask = append(new Constant(new IntConstant(0xFFFF)));
1693       x = append(new LogicOp(Bytecodes::_iand, x, mask));
1694       break;
1695     }
1696     case T_BOOLEAN:
1697     {
1698       Value mask = append(new Constant(new IntConstant(1)));
1699       x = append(new LogicOp(Bytecodes::_iand, x, mask));
1700       break;
1701     }
1702     default:
1703       break;
1704   }
1705 
1706   // Check to see whether we are inlining. If so, Return
1707   // instructions become Gotos to the continuation point.
1708   if (continuation() != nullptr) {
1709 
1710     int invoke_bci = state()->caller_state()->bci();
1711 
1712     if (x != nullptr  && !ignore_return) {
1713       ciMethod* caller = state()->scope()->caller()->method();
1714       Bytecodes::Code invoke_raw_bc = caller->raw_code_at_bci(invoke_bci);
1715       if (invoke_raw_bc == Bytecodes::_invokehandle || invoke_raw_bc == Bytecodes::_invokedynamic) {
1716         ciType* declared_ret_type = caller->get_declared_signature_at_bci(invoke_bci)->return_type();
1717         if (declared_ret_type->is_klass() && x->exact_type() == nullptr &&
1718             x->declared_type() != declared_ret_type && declared_ret_type != compilation()->env()->Object_klass()) {
1719           x = append(new TypeCast(declared_ret_type->as_klass(), x, copy_state_before()));
1720         }
1721       }
1722     }
1723 
1724     assert(!method()->is_synchronized() || InlineSynchronizedMethods, "can not inline synchronized methods yet");
1725 
1726     if (compilation()->env()->dtrace_method_probes()) {
1727       // Report exit from inline methods
1728       Values* args = new Values(1);
1729       args->push(append(new Constant(new MethodConstant(method()))));
1730       append(new RuntimeCall(voidType, "dtrace_method_exit", CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_exit), args));
1731     }
1732 
1733     // If the inlined method is synchronized, the monitor must be
1734     // released before we jump to the continuation block.
1735     if (method()->is_synchronized()) {
1736       assert(state()->locks_size() == 1, "receiver must be locked here");
1737       monitorexit(state()->lock_at(0), SynchronizationEntryBCI);
1738     }
1739 
1740     if (need_mem_bar) {
1741       append(new MemBar(lir_membar_storestore));
1742     }
1743 
1744     // State at end of inlined method is the state of the caller
1745     // without the method parameters on stack, including the
1746     // return value, if any, of the inlined method on operand stack.
1747     set_state(state()->caller_state()->copy_for_parsing());
1748     if (x != nullptr) {
1749       if (!ignore_return) {
1750         state()->push(x->type(), x);
1751       }
1752       if (profile_return() && x->type()->is_object_kind()) {
1753         ciMethod* caller = state()->scope()->method();
1754         profile_return_type(x, method(), caller, invoke_bci);
1755       }
1756     }
1757     Goto* goto_callee = new Goto(continuation(), false);
1758 
1759     // See whether this is the first return; if so, store off some
1760     // of the state for later examination
1761     if (num_returns() == 0) {
1762       set_inline_cleanup_info();
1763     }
1764 
1765     // The current bci() is in the wrong scope, so use the bci() of
1766     // the continuation point.
1767     append_with_bci(goto_callee, scope_data()->continuation()->bci());
1768     incr_num_returns();
1769     return;
1770   }
1771 
1772   state()->truncate_stack(0);
1773   if (method()->is_synchronized()) {
1774     // perform the unlocking before exiting the method
1775     Value receiver;
1776     if (!method()->is_static()) {
1777       receiver = _initial_state->local_at(0);
1778     } else {
1779       receiver = append(new Constant(new ClassConstant(method()->holder())));
1780     }
1781     append_split(new MonitorExit(receiver, state()->unlock()));
1782   }
1783 
1784   if (need_mem_bar) {
1785       append(new MemBar(lir_membar_storestore));
1786   }
1787 
1788   assert(!ignore_return, "Ignoring return value works only for inlining");
1789   append(new Return(x));
1790 }
1791 
1792 Value GraphBuilder::make_constant(ciConstant field_value, ciField* field) {
1793   if (!field_value.is_valid())  return nullptr;
1794 
1795   BasicType field_type = field_value.basic_type();
1796   ValueType* value = as_ValueType(field_value);
1797 
1798   // Attach dimension info to stable arrays.
1799   if (FoldStableValues &&
1800       field->is_stable() && field_type == T_ARRAY && !field_value.is_null_or_zero()) {
1801     ciArray* array = field_value.as_object()->as_array();
1802     jint dimension = field->type()->as_array_klass()->dimension();
1803     value = new StableArrayConstant(array, dimension);
1804   }
1805 
1806   switch (field_type) {
1807     case T_ARRAY:
1808     case T_OBJECT:
1809       if (field_value.as_object()->should_be_constant()) {
1810         return new Constant(value);
1811       }
1812       return nullptr; // Not a constant.
1813     default:
1814       return new Constant(value);
1815   }
1816 }
1817 
1818 void GraphBuilder::copy_inline_content(ciInlineKlass* vk, Value src, int src_off, Value dest, int dest_off, ValueStack* state_before, ciField* enclosing_field) {
1819   for (int i = 0; i < vk->nof_declared_nonstatic_fields(); i++) {
1820     ciField* field = vk->declared_nonstatic_field_at(i);
1821     int offset = field->offset_in_bytes() - vk->payload_offset();
1822     if (field->is_flat()) {
1823       bool needs_atomic_access = !field->is_null_free() || field->is_volatile();
1824       assert(!needs_atomic_access, "Atomic access in non-atomic container");
1825       copy_inline_content(field->type()->as_inline_klass(), src, src_off + offset, dest, dest_off + offset, state_before, enclosing_field);
1826       if (!field->is_null_free()) {
1827         // Nullable, copy the null marker using Unsafe because null markers are no real fields
1828         int null_marker_offset = field->null_marker_offset() - vk->payload_offset();
1829         Value offset = append(new Constant(new LongConstant(src_off + null_marker_offset)));
1830         Value nm = append(new UnsafeGet(T_BOOLEAN, src, offset, false));
1831         offset = append(new Constant(new LongConstant(dest_off + null_marker_offset)));
1832         append(new UnsafePut(T_BOOLEAN, dest, offset, nm, false));
1833       }
1834     } else {
1835       Value value = append(new LoadField(src, src_off + offset, field, false, state_before, false));
1836       StoreField* store = new StoreField(dest, dest_off + offset, field, value, false, state_before, false);
1837       store->set_enclosing_field(enclosing_field);
1838       append(store);
1839     }
1840   }
1841 }
1842 
1843 void GraphBuilder::access_field(Bytecodes::Code code) {
1844   bool will_link;
1845   ciField* field = stream()->get_field(will_link);
1846   ciInstanceKlass* holder = field->holder();
1847   BasicType field_type = field->type()->basic_type();
1848   ValueType* type = as_ValueType(field_type);
1849 
1850   // call will_link again to determine if the field is valid.
1851   const bool needs_patching = !holder->is_loaded() ||
1852                               !field->will_link(method(), code) ||
1853                               (!field->is_flat() && PatchALot);
1854 
1855   ValueStack* state_before = nullptr;
1856   if (!holder->is_initialized() || needs_patching) {
1857     // save state before instruction for debug info when
1858     // deoptimization happens during patching
1859     state_before = copy_state_before();
1860   }
1861 
1862   Value obj = nullptr;
1863   if (code == Bytecodes::_getstatic || code == Bytecodes::_putstatic) {
1864     if (state_before != nullptr) {
1865       // build a patching constant
1866       obj = new Constant(new InstanceConstant(holder->java_mirror()), state_before);
1867     } else {
1868       obj = new Constant(new InstanceConstant(holder->java_mirror()));
1869     }
1870   }
1871 
1872   if (code == Bytecodes::_putfield) {
1873     scope()->set_wrote_fields();
1874     if (field->is_volatile()) {
1875       scope()->set_wrote_volatile();
1876     }
1877     if (field->is_final()) {
1878       scope()->set_wrote_final();
1879     }
1880     if (field->is_stable()) {
1881       scope()->set_wrote_stable();
1882     }
1883   }
1884 
1885   int offset = !needs_patching ? field->offset_in_bytes() : -1;
1886   switch (code) {
1887     case Bytecodes::_getstatic: {
1888       // check for compile-time constants, i.e., initialized static final fields
1889       Value constant = nullptr;
1890       if (field->is_static_constant() && !PatchALot) {
1891         ciConstant field_value = field->constant_value();
1892         assert(!field->is_stable() || !field_value.is_null_or_zero(),
1893                "stable static w/ default value shouldn't be a constant");
1894         constant = make_constant(field_value, field);
1895       } else if (field->is_null_free() && field->type()->as_instance_klass()->is_initialized() &&
1896                  field->type()->as_inline_klass()->is_empty()) {
1897         // Loading from a field of an empty, null-free inline type. Just return the default instance.
1898         constant = new Constant(new InstanceConstant(field->type()->as_inline_klass()->default_instance()));
1899       }
1900       if (constant != nullptr) {
1901         push(type, append(constant));
1902       } else {
1903         if (state_before == nullptr) {
1904           state_before = copy_state_for_exception();
1905         }
1906         LoadField* load_field = new LoadField(append(obj), offset, field, true,
1907                                         state_before, needs_patching);
1908         push(type, append(load_field));
1909       }
1910       break;
1911     }
1912     case Bytecodes::_putstatic: {
1913       Value val = pop(type);
1914       if (state_before == nullptr) {
1915         state_before = copy_state_for_exception();
1916       }
1917       if (field_type == T_BOOLEAN) {
1918         Value mask = append(new Constant(new IntConstant(1)));
1919         val = append(new LogicOp(Bytecodes::_iand, val, mask));
1920       }
1921       if (field->is_null_free()) {
1922         null_check(val);
1923       }
1924       if (field->is_null_free() && field->type()->is_loaded() && field->type()->as_inline_klass()->is_empty()) {
1925         // Storing to a field of an empty, null-free inline type. Ignore.
1926         break;
1927       }
1928       append(new StoreField(append(obj), offset, field, val, true, state_before, needs_patching));
1929       break;
1930     }
1931     case Bytecodes::_getfield: {
1932       // Check for compile-time constants, i.e., trusted final non-static fields.
1933       Value constant = nullptr;
1934       if (state_before == nullptr && field->is_flat()) {
1935         // Save the entire state and re-execute on deopt when accessing flat fields
1936         assert(Interpreter::bytecode_should_reexecute(code), "should reexecute");
1937         state_before = copy_state_before();
1938       }
1939       if (!has_pending_field_access() && !has_pending_load_indexed()) {
1940         obj = apop();
1941         ObjectType* obj_type = obj->type()->as_ObjectType();
1942         if (field->is_null_free() && field->type()->as_instance_klass()->is_initialized()
1943             && field->type()->as_inline_klass()->is_empty()) {
1944           // Loading from a field of an empty, null-free inline type. Just return the default instance.
1945           null_check(obj);
1946           constant = new Constant(new InstanceConstant(field->type()->as_inline_klass()->default_instance()));
1947         } else if (field->is_constant() && !field->is_flat() && obj_type->is_constant() && !PatchALot) {
1948           ciObject* const_oop = obj_type->constant_value();
1949           if (!const_oop->is_null_object() && const_oop->is_loaded()) {
1950             ciConstant field_value = field->constant_value_of(const_oop);
1951             if (field_value.is_valid()) {
1952               if (field->is_null_free() && field_value.is_null_or_zero()) {
1953                 // Non-flat inline type field. Replace null by the default value.
1954                 constant = new Constant(new InstanceConstant(field->type()->as_inline_klass()->default_instance()));
1955               } else {
1956                 constant = make_constant(field_value, field);
1957               }
1958               // For CallSite objects add a dependency for invalidation of the optimization.
1959               if (field->is_call_site_target()) {
1960                 ciCallSite* call_site = const_oop->as_call_site();
1961                 if (!call_site->is_fully_initialized_constant_call_site()) {
1962                   ciMethodHandle* target = field_value.as_object()->as_method_handle();
1963                   dependency_recorder()->assert_call_site_target_value(call_site, target);
1964                 }
1965               }
1966             }
1967           }
1968         }
1969       }
1970       if (constant != nullptr) {
1971         push(type, append(constant));
1972       } else {
1973         if (state_before == nullptr) {
1974           state_before = copy_state_for_exception();
1975         }
1976         if (!field->is_flat()) {
1977           if (has_pending_field_access()) {
1978             assert(!needs_patching, "Can't patch delayed field access");
1979             obj = pending_field_access()->obj();
1980             offset += pending_field_access()->offset() - field->holder()->as_inline_klass()->payload_offset();
1981             field = pending_field_access()->holder()->get_field_by_offset(offset, false);
1982             assert(field != nullptr, "field not found");
1983             set_pending_field_access(nullptr);
1984           } else if (has_pending_load_indexed()) {
1985             assert(!needs_patching, "Can't patch delayed field access");
1986             pending_load_indexed()->update(field, offset - field->holder()->as_inline_klass()->payload_offset());
1987             LoadIndexed* li = pending_load_indexed()->load_instr();
1988             li->set_type(type);
1989             push(type, append(li));
1990             set_pending_load_indexed(nullptr);
1991             break;
1992           }
1993           LoadField* load = new LoadField(obj, offset, field, false, state_before, needs_patching);
1994           Value replacement = !needs_patching ? _memory->load(load) : load;
1995           if (replacement != load) {
1996             assert(replacement->is_linked() || !replacement->can_be_linked(), "should already by linked");
1997             // Writing an (integer) value to a boolean, byte, char or short field includes an implicit narrowing
1998             // conversion. Emit an explicit conversion here to get the correct field value after the write.
1999             switch (field_type) {
2000             case T_BOOLEAN:
2001             case T_BYTE:
2002               replacement = append(new Convert(Bytecodes::_i2b, replacement, type));
2003               break;
2004             case T_CHAR:
2005               replacement = append(new Convert(Bytecodes::_i2c, replacement, type));
2006               break;
2007             case T_SHORT:
2008               replacement = append(new Convert(Bytecodes::_i2s, replacement, type));
2009               break;
2010             default:
2011               break;
2012             }
2013             push(type, replacement);
2014           } else {
2015             push(type, append(load));
2016           }
2017         } else {
2018           // Flat field
2019           assert(!needs_patching, "Can't patch flat inline type field access");
2020           ciInlineKlass* inline_klass = field->type()->as_inline_klass();
2021           bool is_naturally_atomic = inline_klass->nof_declared_nonstatic_fields() <= 1;
2022           bool needs_atomic_access = !field->is_null_free() || (field->is_volatile() && !is_naturally_atomic);
2023           if (needs_atomic_access) {
2024             assert(!has_pending_field_access(), "Pending field accesses are not supported");
2025             LoadField* load = new LoadField(obj, offset, field, false, state_before, needs_patching);
2026             push(type, append(load));
2027           } else {
2028             assert(field->is_null_free(), "must be null-free");
2029             // Look at the next bytecode to check if we can delay the field access
2030             bool can_delay_access = false;
2031             ciBytecodeStream s(method());
2032             s.force_bci(bci());
2033             s.next();
2034             if (s.cur_bc() == Bytecodes::_getfield && !needs_patching) {
2035               ciField* next_field = s.get_field(will_link);
2036               bool next_needs_patching = !next_field->holder()->is_loaded() ||
2037                                          !next_field->will_link(method(), Bytecodes::_getfield) ||
2038                                          PatchALot;
2039               // We can't update the offset for atomic accesses
2040               bool next_needs_atomic_access = !next_field->is_null_free() || next_field->is_volatile();
2041               can_delay_access = C1UseDelayedFlattenedFieldReads && !next_needs_patching && !next_needs_atomic_access;
2042             }
2043             if (can_delay_access) {
2044               if (has_pending_load_indexed()) {
2045                 pending_load_indexed()->update(field, offset - field->holder()->as_inline_klass()->payload_offset());
2046               } else if (has_pending_field_access()) {
2047                 pending_field_access()->inc_offset(offset - field->holder()->as_inline_klass()->payload_offset());
2048               } else {
2049                 null_check(obj);
2050                 DelayedFieldAccess* dfa = new DelayedFieldAccess(obj, field->holder(), field->offset_in_bytes(), state_before);
2051                 set_pending_field_access(dfa);
2052               }
2053             } else {
2054               scope()->set_wrote_final();
2055               scope()->set_wrote_fields();
2056               bool need_membar = false;
2057               if (field->is_null_free() && inline_klass->is_initialized() && inline_klass->is_empty()) {
2058                 apush(append(new Constant(new InstanceConstant(inline_klass->default_instance()))));
2059                 if (has_pending_field_access()) {
2060                   set_pending_field_access(nullptr);
2061                 } else if (has_pending_load_indexed()) {
2062                   set_pending_load_indexed(nullptr);
2063                 }
2064               } else if (has_pending_load_indexed()) {
2065                 assert(!needs_patching, "Can't patch delayed field access");
2066                 pending_load_indexed()->update(field, offset - field->holder()->as_inline_klass()->payload_offset());
2067                 NewInstance* vt = new NewInstance(inline_klass, pending_load_indexed()->state_before(), false, true);
2068                 _memory->new_instance(vt);
2069                 pending_load_indexed()->load_instr()->set_vt(vt);
2070                 apush(append_split(vt));
2071                 append(pending_load_indexed()->load_instr());
2072                 set_pending_load_indexed(nullptr);
2073                 need_membar = true;
2074               } else {
2075                 if (has_pending_field_access()) {
2076                   state_before = pending_field_access()->state_before();
2077                 }
2078                 NewInstance* new_instance = new NewInstance(inline_klass, state_before, false, true);
2079                 _memory->new_instance(new_instance);
2080                 apush(append_split(new_instance));
2081                 if (has_pending_field_access()) {
2082                   copy_inline_content(inline_klass, pending_field_access()->obj(),
2083                                       pending_field_access()->offset() + field->offset_in_bytes() - field->holder()->as_inline_klass()->payload_offset(),
2084                                       new_instance, inline_klass->payload_offset(), state_before);
2085                   set_pending_field_access(nullptr);
2086                 } else {
2087                   copy_inline_content(inline_klass, obj, field->offset_in_bytes(), new_instance, inline_klass->payload_offset(), state_before);
2088                 }
2089                 need_membar = true;
2090               }
2091               if (need_membar) {
2092                 // If we allocated a new instance ensure the stores to copy the
2093                 // field contents are visible before any subsequent store that
2094                 // publishes this reference.
2095                 append(new MemBar(lir_membar_storestore));
2096               }
2097             }
2098           }
2099         }
2100       }
2101       break;
2102     }
2103     case Bytecodes::_putfield: {
2104       Value val = pop(type);
2105       obj = apop();
2106       if (state_before == nullptr) {
2107         state_before = copy_state_for_exception();
2108       }
2109       if (field_type == T_BOOLEAN) {
2110         Value mask = append(new Constant(new IntConstant(1)));
2111         val = append(new LogicOp(Bytecodes::_iand, val, mask));
2112       }
2113       if (field->is_null_free() && field->type()->is_loaded() && field->type()->as_inline_klass()->is_empty()) {
2114         // Storing to a field of an empty, null-free inline type. Ignore.
2115         null_check(obj);
2116         null_check(val);
2117       } else if (!field->is_flat()) {
2118         if (field->is_null_free()) {
2119           null_check(val);
2120         }
2121         StoreField* store = new StoreField(obj, offset, field, val, false, state_before, needs_patching);
2122         if (!needs_patching) store = _memory->store(store);
2123         if (store != nullptr) {
2124           append(store);
2125         }
2126       } else {
2127         // Flat field
2128         assert(!needs_patching, "Can't patch flat inline type field access");
2129         ciInlineKlass* inline_klass = field->type()->as_inline_klass();
2130         bool is_naturally_atomic = inline_klass->nof_declared_nonstatic_fields() <= 1;
2131         bool needs_atomic_access = !field->is_null_free() || (field->is_volatile() && !is_naturally_atomic);
2132         if (needs_atomic_access) {
2133           if (field->is_null_free()) {
2134             null_check(val);
2135           }
2136           append(new StoreField(obj, offset, field, val, false, state_before, needs_patching));
2137         } else {
2138           assert(field->is_null_free(), "must be null-free");
2139           copy_inline_content(inline_klass, val, inline_klass->payload_offset(), obj, offset, state_before, field);
2140         }
2141       }
2142       break;
2143     }
2144     default:
2145       ShouldNotReachHere();
2146       break;
2147   }
2148 }
2149 
2150 Dependencies* GraphBuilder::dependency_recorder() const {
2151   assert(DeoptC1, "need debug information");
2152   return compilation()->dependency_recorder();
2153 }
2154 
2155 // How many arguments do we want to profile?
2156 Values* GraphBuilder::args_list_for_profiling(ciMethod* target, int& start, bool may_have_receiver) {
2157   int n = 0;
2158   bool has_receiver = may_have_receiver && Bytecodes::has_receiver(method()->java_code_at_bci(bci()));
2159   start = has_receiver ? 1 : 0;
2160   if (profile_arguments()) {
2161     ciProfileData* data = method()->method_data()->bci_to_data(bci());
2162     if (data != nullptr && (data->is_CallTypeData() || data->is_VirtualCallTypeData())) {
2163       n = data->is_CallTypeData() ? data->as_CallTypeData()->number_of_arguments() : data->as_VirtualCallTypeData()->number_of_arguments();
2164     }
2165   }
2166   // If we are inlining then we need to collect arguments to profile parameters for the target
2167   if (profile_parameters() && target != nullptr) {
2168     if (target->method_data() != nullptr && target->method_data()->parameters_type_data() != nullptr) {
2169       // The receiver is profiled on method entry so it's included in
2170       // the number of parameters but here we're only interested in
2171       // actual arguments.
2172       n = MAX2(n, target->method_data()->parameters_type_data()->number_of_parameters() - start);
2173     }
2174   }
2175   if (n > 0) {
2176     return new Values(n);
2177   }
2178   return nullptr;
2179 }
2180 
2181 void GraphBuilder::check_args_for_profiling(Values* obj_args, int expected) {
2182 #ifdef ASSERT
2183   bool ignored_will_link;
2184   ciSignature* declared_signature = nullptr;
2185   ciMethod* real_target = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
2186   assert(expected == obj_args->capacity() || real_target->is_method_handle_intrinsic(), "missed on arg?");
2187 #endif
2188 }
2189 
2190 // Collect arguments that we want to profile in a list
2191 Values* GraphBuilder::collect_args_for_profiling(Values* args, ciMethod* target, bool may_have_receiver) {
2192   int start = 0;
2193   Values* obj_args = args_list_for_profiling(target, start, may_have_receiver);
2194   if (obj_args == nullptr) {
2195     return nullptr;
2196   }
2197   int s = obj_args->capacity();
2198   // if called through method handle invoke, some arguments may have been popped
2199   for (int i = start, j = 0; j < s && i < args->length(); i++) {
2200     if (args->at(i)->type()->is_object_kind()) {
2201       obj_args->push(args->at(i));
2202       j++;
2203     }
2204   }
2205   check_args_for_profiling(obj_args, s);
2206   return obj_args;
2207 }
2208 
2209 void GraphBuilder::invoke(Bytecodes::Code code) {
2210   bool will_link;
2211   ciSignature* declared_signature = nullptr;
2212   ciMethod*             target = stream()->get_method(will_link, &declared_signature);
2213   ciKlass*              holder = stream()->get_declared_method_holder();
2214   const Bytecodes::Code bc_raw = stream()->cur_bc_raw();
2215   assert(declared_signature != nullptr, "cannot be null");
2216   assert(will_link == target->is_loaded(), "");
2217   JFR_ONLY(Jfr::on_resolution(this, holder, target); CHECK_BAILOUT();)
2218 
2219   ciInstanceKlass* klass = target->holder();
2220   assert(!target->is_loaded() || klass->is_loaded(), "loaded target must imply loaded klass");
2221 
2222   // check if CHA possible: if so, change the code to invoke_special
2223   ciInstanceKlass* calling_klass = method()->holder();
2224   ciInstanceKlass* callee_holder = ciEnv::get_instance_klass_for_declared_method_holder(holder);
2225   ciInstanceKlass* actual_recv = callee_holder;
2226 
2227   CompileLog* log = compilation()->log();
2228   if (log != nullptr)
2229       log->elem("call method='%d' instr='%s'",
2230                 log->identify(target),
2231                 Bytecodes::name(code));
2232 
2233   // Some methods are obviously bindable without any type checks so
2234   // convert them directly to an invokespecial or invokestatic.
2235   if (target->is_loaded() && !target->is_abstract() && target->can_be_statically_bound()) {
2236     switch (bc_raw) {
2237     case Bytecodes::_invokeinterface:
2238       // convert to invokespecial if the target is the private interface method.
2239       if (target->is_private()) {
2240         assert(holder->is_interface(), "How did we get a non-interface method here!");
2241         code = Bytecodes::_invokespecial;
2242       }
2243       break;
2244     case Bytecodes::_invokevirtual:
2245       code = Bytecodes::_invokespecial;
2246       break;
2247     case Bytecodes::_invokehandle:
2248       code = target->is_static() ? Bytecodes::_invokestatic : Bytecodes::_invokespecial;
2249       break;
2250     default:
2251       break;
2252     }
2253   } else {
2254     if (bc_raw == Bytecodes::_invokehandle) {
2255       assert(!will_link, "should come here only for unlinked call");
2256       code = Bytecodes::_invokespecial;
2257     }
2258   }
2259 
2260   if (code == Bytecodes::_invokespecial) {
2261     // Additional receiver subtype checks for interface calls via invokespecial or invokeinterface.
2262     ciKlass* receiver_constraint = nullptr;
2263 
2264     if (bc_raw == Bytecodes::_invokeinterface) {
2265       receiver_constraint = holder;
2266     } else if (bc_raw == Bytecodes::_invokespecial && !target->is_object_constructor() && calling_klass->is_interface()) {
2267       receiver_constraint = calling_klass;
2268     }
2269 
2270     if (receiver_constraint != nullptr) {
2271       int index = state()->stack_size() - (target->arg_size_no_receiver() + 1);
2272       Value receiver = state()->stack_at(index);
2273       CheckCast* c = new CheckCast(receiver_constraint, receiver, copy_state_before());
2274       // go to uncommon_trap when checkcast fails
2275       c->set_invokespecial_receiver_check();
2276       state()->stack_at_put(index, append_split(c));
2277     }
2278   }
2279 
2280   // Push appendix argument (MethodType, CallSite, etc.), if one.
2281   bool patch_for_appendix = false;
2282   int patching_appendix_arg = 0;
2283   if (Bytecodes::has_optional_appendix(bc_raw) && (!will_link || PatchALot)) {
2284     Value arg = append(new Constant(new ObjectConstant(compilation()->env()->unloaded_ciinstance()), copy_state_before()));
2285     apush(arg);
2286     patch_for_appendix = true;
2287     patching_appendix_arg = (will_link && stream()->has_appendix()) ? 0 : 1;
2288   } else if (stream()->has_appendix()) {
2289     ciObject* appendix = stream()->get_appendix();
2290     Value arg = append(new Constant(new ObjectConstant(appendix)));
2291     apush(arg);
2292   }
2293 
2294   ciMethod* cha_monomorphic_target = nullptr;
2295   ciMethod* exact_target = nullptr;
2296   Value better_receiver = nullptr;
2297   if (UseCHA && DeoptC1 && target->is_loaded() &&
2298       !(// %%% FIXME: Are both of these relevant?
2299         target->is_method_handle_intrinsic() ||
2300         target->is_compiled_lambda_form()) &&
2301       !patch_for_appendix) {
2302     Value receiver = nullptr;
2303     ciInstanceKlass* receiver_klass = nullptr;
2304     bool type_is_exact = false;
2305     // try to find a precise receiver type
2306     if (will_link && !target->is_static()) {
2307       int index = state()->stack_size() - (target->arg_size_no_receiver() + 1);
2308       receiver = state()->stack_at(index);
2309       ciType* type = receiver->exact_type();
2310       if (type != nullptr && type->is_loaded()) {
2311         assert(!type->is_instance_klass() || !type->as_instance_klass()->is_interface(), "Must not be an interface");
2312         // Detects non-interface instances, primitive arrays, and some object arrays.
2313         // Array receivers can only call Object methods, so we should be able to allow
2314         // all object arrays here too, even those with unloaded types.
2315         receiver_klass = (ciInstanceKlass*) type;
2316         type_is_exact = true;
2317       }
2318       if (type == nullptr) {
2319         type = receiver->declared_type();
2320         if (type != nullptr && type->is_loaded() &&
2321             type->is_instance_klass() && !type->as_instance_klass()->is_interface()) {
2322           receiver_klass = (ciInstanceKlass*) type;
2323           if (receiver_klass->is_leaf_type() && !receiver_klass->is_final()) {
2324             // Insert a dependency on this type since
2325             // find_monomorphic_target may assume it's already done.
2326             dependency_recorder()->assert_leaf_type(receiver_klass);
2327             type_is_exact = true;
2328           }
2329         }
2330       }
2331     }
2332     if (receiver_klass != nullptr && type_is_exact &&
2333         receiver_klass->is_loaded() && code != Bytecodes::_invokespecial) {
2334       // If we have the exact receiver type we can bind directly to
2335       // the method to call.
2336       exact_target = target->resolve_invoke(calling_klass, receiver_klass);
2337       if (exact_target != nullptr) {
2338         target = exact_target;
2339         code = Bytecodes::_invokespecial;
2340       }
2341     }
2342     if (receiver_klass != nullptr &&
2343         receiver_klass->is_subtype_of(actual_recv) &&
2344         actual_recv->is_initialized()) {
2345       actual_recv = receiver_klass;
2346     }
2347 
2348     if ((code == Bytecodes::_invokevirtual && callee_holder->is_initialized()) ||
2349         (code == Bytecodes::_invokeinterface && callee_holder->is_initialized() && !actual_recv->is_interface())) {
2350       // Use CHA on the receiver to select a more precise method.
2351       cha_monomorphic_target = target->find_monomorphic_target(calling_klass, callee_holder, actual_recv);
2352     } else if (code == Bytecodes::_invokeinterface && callee_holder->is_loaded() && receiver != nullptr) {
2353       assert(callee_holder->is_interface(), "invokeinterface to non interface?");
2354       // If there is only one implementor of this interface then we
2355       // may be able bind this invoke directly to the implementing
2356       // klass but we need both a dependence on the single interface
2357       // and on the method we bind to.  Additionally since all we know
2358       // about the receiver type is the it's supposed to implement the
2359       // interface we have to insert a check that it's the class we
2360       // expect.  Interface types are not checked by the verifier so
2361       // they are roughly equivalent to Object.
2362       // The number of implementors for declared_interface is less or
2363       // equal to the number of implementors for target->holder() so
2364       // if number of implementors of target->holder() == 1 then
2365       // number of implementors for decl_interface is 0 or 1. If
2366       // it's 0 then no class implements decl_interface and there's
2367       // no point in inlining.
2368       ciInstanceKlass* declared_interface = callee_holder;
2369       ciInstanceKlass* singleton = declared_interface->unique_implementor();
2370       if (singleton != nullptr) {
2371         assert(singleton != declared_interface, "not a unique implementor");
2372         cha_monomorphic_target = target->find_monomorphic_target(calling_klass, declared_interface, singleton);
2373         if (cha_monomorphic_target != nullptr) {
2374           ciInstanceKlass* holder = cha_monomorphic_target->holder();
2375           ciInstanceKlass* constraint = (holder->is_subtype_of(singleton) ? holder : singleton); // avoid upcasts
2376           if (holder != compilation()->env()->Object_klass() &&
2377               (!type_is_exact || receiver_klass->is_subtype_of(constraint))) {
2378             actual_recv = declared_interface;
2379 
2380             // insert a check it's really the expected class.
2381             CheckCast* c = new CheckCast(constraint, receiver, copy_state_for_exception());
2382             c->set_incompatible_class_change_check();
2383             c->set_direct_compare(constraint->is_final());
2384             // pass the result of the checkcast so that the compiler has
2385             // more accurate type info in the inlinee
2386             better_receiver = append_split(c);
2387 
2388             dependency_recorder()->assert_unique_implementor(declared_interface, singleton);
2389           } else {
2390             cha_monomorphic_target = nullptr;
2391           }
2392         }
2393       }
2394     }
2395   }
2396 
2397   if (cha_monomorphic_target != nullptr) {
2398     assert(!target->can_be_statically_bound() || target == cha_monomorphic_target, "");
2399     assert(!cha_monomorphic_target->is_abstract(), "");
2400     if (!cha_monomorphic_target->can_be_statically_bound(actual_recv)) {
2401       // If we inlined because CHA revealed only a single target method,
2402       // then we are dependent on that target method not getting overridden
2403       // by dynamic class loading.  Be sure to test the "static" receiver
2404       // dest_method here, as opposed to the actual receiver, which may
2405       // falsely lead us to believe that the receiver is final or private.
2406       dependency_recorder()->assert_unique_concrete_method(actual_recv, cha_monomorphic_target, callee_holder, target);
2407     }
2408     code = Bytecodes::_invokespecial;
2409   }
2410 
2411   // check if we could do inlining
2412   if (!PatchALot && Inline && target->is_loaded() && !patch_for_appendix &&
2413       callee_holder->is_loaded()) { // the effect of symbolic reference resolution
2414 
2415     // callee is known => check if we have static binding
2416     if ((code == Bytecodes::_invokestatic && klass->is_initialized()) || // invokestatic involves an initialization barrier on declaring class
2417         code == Bytecodes::_invokespecial ||
2418         (code == Bytecodes::_invokevirtual && target->is_final_method()) ||
2419         code == Bytecodes::_invokedynamic) {
2420       // static binding => check if callee is ok
2421       ciMethod* inline_target = (cha_monomorphic_target != nullptr) ? cha_monomorphic_target : target;
2422       bool holder_known = (cha_monomorphic_target != nullptr) || (exact_target != nullptr);
2423       bool success = try_inline(inline_target, holder_known, false /* ignore_return */, code, better_receiver);
2424 
2425       CHECK_BAILOUT();
2426       clear_inline_bailout();
2427 
2428       if (success) {
2429         // Register dependence if JVMTI has either breakpoint
2430         // setting or hotswapping of methods capabilities since they may
2431         // cause deoptimization.
2432         if (compilation()->env()->jvmti_can_hotswap_or_post_breakpoint()) {
2433           dependency_recorder()->assert_evol_method(inline_target);
2434         }
2435         return;
2436       }
2437     } else {
2438       print_inlining(target, "no static binding", /*success*/ false);
2439     }
2440   } else {
2441     print_inlining(target, "not inlineable", /*success*/ false);
2442   }
2443 
2444   // If we attempted an inline which did not succeed because of a
2445   // bailout during construction of the callee graph, the entire
2446   // compilation has to be aborted. This is fairly rare and currently
2447   // seems to only occur for jasm-generated classes which contain
2448   // jsr/ret pairs which are not associated with finally clauses and
2449   // do not have exception handlers in the containing method, and are
2450   // therefore not caught early enough to abort the inlining without
2451   // corrupting the graph. (We currently bail out with a non-empty
2452   // stack at a ret in these situations.)
2453   CHECK_BAILOUT();
2454 
2455   // inlining not successful => standard invoke
2456   ValueType* result_type = as_ValueType(declared_signature->return_type());
2457   ValueStack* state_before = copy_state_exhandling();
2458 
2459   // The bytecode (code) might change in this method so we are checking this very late.
2460   const bool has_receiver =
2461     code == Bytecodes::_invokespecial   ||
2462     code == Bytecodes::_invokevirtual   ||
2463     code == Bytecodes::_invokeinterface;
2464   Values* args = state()->pop_arguments(target->arg_size_no_receiver() + patching_appendix_arg);
2465   Value recv = has_receiver ? apop() : nullptr;
2466 
2467   // A null check is required here (when there is a receiver) for any of the following cases
2468   // - invokespecial, always need a null check.
2469   // - invokevirtual, when the target is final and loaded. Calls to final targets will become optimized
2470   //   and require null checking. If the target is loaded a null check is emitted here.
2471   //   If the target isn't loaded the null check must happen after the call resolution. We achieve that
2472   //   by using the target methods unverified entry point (see CompiledIC::compute_monomorphic_entry).
2473   //   (The JVM specification requires that LinkageError must be thrown before a NPE. An unloaded target may
2474   //   potentially fail, and can't have the null check before the resolution.)
2475   // - A call that will be profiled. (But we can't add a null check when the target is unloaded, by the same
2476   //   reason as above, so calls with a receiver to unloaded targets can't be profiled.)
2477   //
2478   // Normal invokevirtual will perform the null check during lookup
2479 
2480   bool need_null_check = (code == Bytecodes::_invokespecial) ||
2481       (target->is_loaded() && (target->is_final_method() || (is_profiling() && profile_calls())));
2482 
2483   if (need_null_check) {
2484     if (recv != nullptr) {
2485       null_check(recv);
2486     }
2487 
2488     if (is_profiling()) {
2489       // Note that we'd collect profile data in this method if we wanted it.
2490       compilation()->set_would_profile(true);
2491 
2492       if (profile_calls()) {
2493         assert(cha_monomorphic_target == nullptr || exact_target == nullptr, "both can not be set");
2494         ciKlass* target_klass = nullptr;
2495         if (cha_monomorphic_target != nullptr) {
2496           target_klass = cha_monomorphic_target->holder();
2497         } else if (exact_target != nullptr) {
2498           target_klass = exact_target->holder();
2499         }
2500         profile_call(target, recv, target_klass, collect_args_for_profiling(args, nullptr, false), false);
2501       }
2502     }
2503   }
2504 
2505   Invoke* result = new Invoke(code, result_type, recv, args, target, state_before);
2506   // push result
2507   append_split(result);
2508 
2509   if (result_type != voidType) {
2510     push(result_type, round_fp(result));
2511   }
2512   if (profile_return() && result_type->is_object_kind()) {
2513     profile_return_type(result, target);
2514   }
2515 }
2516 
2517 
2518 void GraphBuilder::new_instance(int klass_index) {
2519   ValueStack* state_before = copy_state_exhandling();
2520   ciKlass* klass = stream()->get_klass();
2521   assert(klass->is_instance_klass(), "must be an instance klass");
2522   if (!stream()->is_unresolved_klass() && klass->is_inlinetype() &&
2523       klass->as_inline_klass()->is_initialized() && klass->as_inline_klass()->is_empty()) {
2524     ciInlineKlass* vk = klass->as_inline_klass();
2525     apush(append(new Constant(new InstanceConstant(vk->default_instance()))));
2526   } else {
2527     NewInstance* new_instance = new NewInstance(klass->as_instance_klass(), state_before, stream()->is_unresolved_klass(), false);
2528     _memory->new_instance(new_instance);
2529     apush(append_split(new_instance));
2530   }
2531 }
2532 
2533 void GraphBuilder::new_type_array() {
2534   ValueStack* state_before = copy_state_exhandling();
2535   apush(append_split(new NewTypeArray(ipop(), (BasicType)stream()->get_index(), state_before, true)));
2536 }
2537 
2538 
2539 void GraphBuilder::new_object_array() {
2540   ciKlass* klass = stream()->get_klass();
2541   ValueStack* state_before = !klass->is_loaded() || PatchALot ? copy_state_before() : copy_state_exhandling();
2542   NewArray* n = new NewObjectArray(klass, ipop(), state_before);
2543   apush(append_split(n));
2544 }
2545 
2546 
2547 bool GraphBuilder::direct_compare(ciKlass* k) {
2548   if (k->is_loaded() && k->is_instance_klass() && !UseSlowPath) {
2549     ciInstanceKlass* ik = k->as_instance_klass();
2550     if (ik->is_final()) {
2551       return true;
2552     } else {
2553       if (DeoptC1 && UseCHA && !(ik->has_subklass() || ik->is_interface())) {
2554         // test class is leaf class
2555         dependency_recorder()->assert_leaf_type(ik);
2556         return true;
2557       }
2558     }
2559   }
2560   return false;
2561 }
2562 
2563 
2564 void GraphBuilder::check_cast(int klass_index) {
2565   ciKlass* klass = stream()->get_klass();
2566   ValueStack* state_before = !klass->is_loaded() || PatchALot ? copy_state_before() : copy_state_for_exception();
2567   CheckCast* c = new CheckCast(klass, apop(), state_before);
2568   apush(append_split(c));
2569   c->set_direct_compare(direct_compare(klass));
2570 
2571   if (is_profiling()) {
2572     // Note that we'd collect profile data in this method if we wanted it.
2573     compilation()->set_would_profile(true);
2574 
2575     if (profile_checkcasts()) {
2576       c->set_profiled_method(method());
2577       c->set_profiled_bci(bci());
2578       c->set_should_profile(true);
2579     }
2580   }
2581 }
2582 
2583 
2584 void GraphBuilder::instance_of(int klass_index) {
2585   ciKlass* klass = stream()->get_klass();
2586   ValueStack* state_before = !klass->is_loaded() || PatchALot ? copy_state_before() : copy_state_exhandling();
2587   InstanceOf* i = new InstanceOf(klass, apop(), state_before);
2588   ipush(append_split(i));
2589   i->set_direct_compare(direct_compare(klass));
2590 
2591   if (is_profiling()) {
2592     // Note that we'd collect profile data in this method if we wanted it.
2593     compilation()->set_would_profile(true);
2594 
2595     if (profile_checkcasts()) {
2596       i->set_profiled_method(method());
2597       i->set_profiled_bci(bci());
2598       i->set_should_profile(true);
2599     }
2600   }
2601 }
2602 
2603 
2604 void GraphBuilder::monitorenter(Value x, int bci) {
2605   bool maybe_inlinetype = false;
2606   if (bci == InvocationEntryBci) {
2607     // Called by GraphBuilder::inline_sync_entry.
2608 #ifdef ASSERT
2609     ciType* obj_type = x->declared_type();
2610     assert(obj_type == nullptr || !obj_type->is_inlinetype(), "inline types cannot have synchronized methods");
2611 #endif
2612   } else {
2613     // We are compiling a monitorenter bytecode
2614     if (EnableValhalla) {
2615       ciType* obj_type = x->declared_type();
2616       if (obj_type == nullptr || obj_type->as_klass()->can_be_inline_klass()) {
2617         // If we're (possibly) locking on an inline type, check for markWord::always_locked_pattern
2618         // and throw IMSE. (obj_type is null for Phi nodes, so let's just be conservative).
2619         maybe_inlinetype = true;
2620       }
2621     }
2622   }
2623 
2624   // save state before locking in case of deoptimization after a NullPointerException
2625   ValueStack* state_before = copy_state_for_exception_with_bci(bci);
2626   append_with_bci(new MonitorEnter(x, state()->lock(x), state_before, maybe_inlinetype), bci);
2627   kill_all();
2628 }
2629 
2630 
2631 void GraphBuilder::monitorexit(Value x, int bci) {
2632   append_with_bci(new MonitorExit(x, state()->unlock()), bci);
2633   kill_all();
2634 }
2635 
2636 
2637 void GraphBuilder::new_multi_array(int dimensions) {
2638   ciKlass* klass = stream()->get_klass();
2639   ValueStack* state_before = !klass->is_loaded() || PatchALot ? copy_state_before() : copy_state_exhandling();
2640 
2641   Values* dims = new Values(dimensions, dimensions, nullptr);
2642   // fill in all dimensions
2643   int i = dimensions;
2644   while (i-- > 0) dims->at_put(i, ipop());
2645   // create array
2646   NewArray* n = new NewMultiArray(klass, dims, state_before);
2647   apush(append_split(n));
2648 }
2649 
2650 
2651 void GraphBuilder::throw_op(int bci) {
2652   // We require that the debug info for a Throw be the "state before"
2653   // the Throw (i.e., exception oop is still on TOS)
2654   ValueStack* state_before = copy_state_before_with_bci(bci);
2655   Throw* t = new Throw(apop(), state_before);
2656   // operand stack not needed after a throw
2657   state()->truncate_stack(0);
2658   append_with_bci(t, bci);
2659 }
2660 
2661 
2662 Value GraphBuilder::round_fp(Value fp_value) {
2663   if (strict_fp_requires_explicit_rounding) {
2664 #ifdef IA32
2665     // no rounding needed if SSE2 is used
2666     if (UseSSE < 2) {
2667       // Must currently insert rounding node for doubleword values that
2668       // are results of expressions (i.e., not loads from memory or
2669       // constants)
2670       if (fp_value->type()->tag() == doubleTag &&
2671           fp_value->as_Constant() == nullptr &&
2672           fp_value->as_Local() == nullptr &&       // method parameters need no rounding
2673           fp_value->as_RoundFP() == nullptr) {
2674         return append(new RoundFP(fp_value));
2675       }
2676     }
2677 #else
2678     Unimplemented();
2679 #endif // IA32
2680   }
2681   return fp_value;
2682 }
2683 
2684 
2685 Instruction* GraphBuilder::append_with_bci(Instruction* instr, int bci) {
2686   Canonicalizer canon(compilation(), instr, bci);
2687   Instruction* i1 = canon.canonical();
2688   if (i1->is_linked() || !i1->can_be_linked()) {
2689     // Canonicalizer returned an instruction which was already
2690     // appended so simply return it.
2691     return i1;
2692   }
2693 
2694   if (UseLocalValueNumbering) {
2695     // Lookup the instruction in the ValueMap and add it to the map if
2696     // it's not found.
2697     Instruction* i2 = vmap()->find_insert(i1);
2698     if (i2 != i1) {
2699       // found an entry in the value map, so just return it.
2700       assert(i2->is_linked(), "should already be linked");
2701       return i2;
2702     }
2703     ValueNumberingEffects vne(vmap());
2704     i1->visit(&vne);
2705   }
2706 
2707   // i1 was not eliminated => append it
2708   assert(i1->next() == nullptr, "shouldn't already be linked");
2709   _last = _last->set_next(i1, canon.bci());
2710 
2711   if (++_instruction_count >= InstructionCountCutoff && !bailed_out()) {
2712     // set the bailout state but complete normal processing.  We
2713     // might do a little more work before noticing the bailout so we
2714     // want processing to continue normally until it's noticed.
2715     bailout("Method and/or inlining is too large");
2716   }
2717 
2718 #ifndef PRODUCT
2719   if (PrintIRDuringConstruction) {
2720     InstructionPrinter ip;
2721     ip.print_line(i1);
2722     if (Verbose) {
2723       state()->print();
2724     }
2725   }
2726 #endif
2727 
2728   // save state after modification of operand stack for StateSplit instructions
2729   StateSplit* s = i1->as_StateSplit();
2730   if (s != nullptr) {
2731     if (EliminateFieldAccess) {
2732       Intrinsic* intrinsic = s->as_Intrinsic();
2733       if (s->as_Invoke() != nullptr || (intrinsic && !intrinsic->preserves_state())) {
2734         _memory->kill();
2735       }
2736     }
2737     s->set_state(state()->copy(ValueStack::StateAfter, canon.bci()));
2738   }
2739 
2740   // set up exception handlers for this instruction if necessary
2741   if (i1->can_trap()) {
2742     i1->set_exception_handlers(handle_exception(i1));
2743     assert(i1->exception_state() != nullptr || !i1->needs_exception_state() || bailed_out(), "handle_exception must set exception state");
2744   }
2745   return i1;
2746 }
2747 
2748 
2749 Instruction* GraphBuilder::append(Instruction* instr) {
2750   assert(instr->as_StateSplit() == nullptr || instr->as_BlockEnd() != nullptr, "wrong append used");
2751   return append_with_bci(instr, bci());
2752 }
2753 
2754 
2755 Instruction* GraphBuilder::append_split(StateSplit* instr) {
2756   return append_with_bci(instr, bci());
2757 }
2758 
2759 
2760 void GraphBuilder::null_check(Value value) {
2761   if (value->as_NewArray() != nullptr || value->as_NewInstance() != nullptr) {
2762     return;
2763   } else {
2764     Constant* con = value->as_Constant();
2765     if (con) {
2766       ObjectType* c = con->type()->as_ObjectType();
2767       if (c && c->is_loaded()) {
2768         ObjectConstant* oc = c->as_ObjectConstant();
2769         if (!oc || !oc->value()->is_null_object()) {
2770           return;
2771         }
2772       }
2773     }
2774     if (value->is_null_free()) return;
2775   }
2776   append(new NullCheck(value, copy_state_for_exception()));
2777 }
2778 
2779 
2780 
2781 XHandlers* GraphBuilder::handle_exception(Instruction* instruction) {
2782   if (!has_handler() && (!instruction->needs_exception_state() || instruction->exception_state() != nullptr)) {
2783     assert(instruction->exception_state() == nullptr
2784            || instruction->exception_state()->kind() == ValueStack::EmptyExceptionState
2785            || (instruction->exception_state()->kind() == ValueStack::ExceptionState && _compilation->env()->should_retain_local_variables()),
2786            "exception_state should be of exception kind");
2787     return new XHandlers();
2788   }
2789 
2790   XHandlers*  exception_handlers = new XHandlers();
2791   ScopeData*  cur_scope_data = scope_data();
2792   ValueStack* cur_state = instruction->state_before();
2793   ValueStack* prev_state = nullptr;
2794   int scope_count = 0;
2795 
2796   assert(cur_state != nullptr, "state_before must be set");
2797   do {
2798     int cur_bci = cur_state->bci();
2799     assert(cur_scope_data->scope() == cur_state->scope(), "scopes do not match");
2800     assert(cur_bci == SynchronizationEntryBCI || cur_bci == cur_scope_data->stream()->cur_bci()
2801            || has_pending_field_access() || has_pending_load_indexed(), "invalid bci");
2802 
2803 
2804     // join with all potential exception handlers
2805     XHandlers* list = cur_scope_data->xhandlers();
2806     const int n = list->length();
2807     for (int i = 0; i < n; i++) {
2808       XHandler* h = list->handler_at(i);
2809       if (h->covers(cur_bci)) {
2810         // h is a potential exception handler => join it
2811         compilation()->set_has_exception_handlers(true);
2812 
2813         BlockBegin* entry = h->entry_block();
2814         if (entry == block()) {
2815           // It's acceptable for an exception handler to cover itself
2816           // but we don't handle that in the parser currently.  It's
2817           // very rare so we bailout instead of trying to handle it.
2818           BAILOUT_("exception handler covers itself", exception_handlers);
2819         }
2820         assert(entry->bci() == h->handler_bci(), "must match");
2821         assert(entry->bci() == -1 || entry == cur_scope_data->block_at(entry->bci()), "blocks must correspond");
2822 
2823         // previously this was a BAILOUT, but this is not necessary
2824         // now because asynchronous exceptions are not handled this way.
2825         assert(entry->state() == nullptr || cur_state->total_locks_size() == entry->state()->total_locks_size(), "locks do not match");
2826 
2827         // xhandler start with an empty expression stack
2828         if (cur_state->stack_size() != 0) {
2829           // locals are preserved
2830           // stack will be truncated
2831           cur_state = cur_state->copy(ValueStack::ExceptionState, cur_state->bci());
2832         }
2833         if (instruction->exception_state() == nullptr) {
2834           instruction->set_exception_state(cur_state);
2835         }
2836 
2837         // Note: Usually this join must work. However, very
2838         // complicated jsr-ret structures where we don't ret from
2839         // the subroutine can cause the objects on the monitor
2840         // stacks to not match because blocks can be parsed twice.
2841         // The only test case we've seen so far which exhibits this
2842         // problem is caught by the infinite recursion test in
2843         // GraphBuilder::jsr() if the join doesn't work.
2844         if (!entry->try_merge(cur_state, compilation()->has_irreducible_loops())) {
2845           BAILOUT_("error while joining with exception handler, prob. due to complicated jsr/rets", exception_handlers);
2846         }
2847 
2848         // add current state for correct handling of phi functions at begin of xhandler
2849         int phi_operand = entry->add_exception_state(cur_state);
2850 
2851         // add entry to the list of xhandlers of this block
2852         _block->add_exception_handler(entry);
2853 
2854         // add back-edge from xhandler entry to this block
2855         if (!entry->is_predecessor(_block)) {
2856           entry->add_predecessor(_block);
2857         }
2858 
2859         // clone XHandler because phi_operand and scope_count can not be shared
2860         XHandler* new_xhandler = new XHandler(h);
2861         new_xhandler->set_phi_operand(phi_operand);
2862         new_xhandler->set_scope_count(scope_count);
2863         exception_handlers->append(new_xhandler);
2864 
2865         // fill in exception handler subgraph lazily
2866         assert(!entry->is_set(BlockBegin::was_visited_flag), "entry must not be visited yet");
2867         cur_scope_data->add_to_work_list(entry);
2868 
2869         // stop when reaching catchall
2870         if (h->catch_type() == 0) {
2871           return exception_handlers;
2872         }
2873       }
2874     }
2875 
2876     if (exception_handlers->length() == 0) {
2877       // This scope and all callees do not handle exceptions, so the local
2878       // variables of this scope are not needed. However, the scope itself is
2879       // required for a correct exception stack trace -> clear out the locals.
2880       // Stack and locals are invalidated but not truncated in caller state.
2881       if (prev_state != nullptr) {
2882         assert(instruction->exception_state() != nullptr, "missed set?");
2883         ValueStack::Kind exc_kind = ValueStack::empty_exception_kind(true /* caller */);
2884         cur_state = cur_state->copy(exc_kind, cur_state->bci());
2885         // reset caller exception state
2886         prev_state->set_caller_state(cur_state);
2887       } else {
2888         assert(instruction->exception_state() == nullptr, "already set");
2889         // set instruction exception state
2890         // truncate stack
2891         ValueStack::Kind exc_kind = ValueStack::empty_exception_kind();
2892         cur_state = cur_state->copy(exc_kind, cur_state->bci());
2893         instruction->set_exception_state(cur_state);
2894       }
2895     }
2896 
2897     // Set up iteration for next time.
2898     // If parsing a jsr, do not grab exception handlers from the
2899     // parent scopes for this method (already got them, and they
2900     // needed to be cloned)
2901 
2902     while (cur_scope_data->parsing_jsr()) {
2903       cur_scope_data = cur_scope_data->parent();
2904     }
2905 
2906     assert(cur_scope_data->scope() == cur_state->scope(), "scopes do not match");
2907     assert(cur_state->locks_size() == 0 || cur_state->locks_size() == 1, "unlocking must be done in a catchall exception handler");
2908 
2909     prev_state = cur_state;
2910     cur_state = cur_state->caller_state();
2911     cur_scope_data = cur_scope_data->parent();
2912     scope_count++;
2913   } while (cur_scope_data != nullptr);
2914 
2915   return exception_handlers;
2916 }
2917 
2918 
2919 // Helper class for simplifying Phis.
2920 class PhiSimplifier : public BlockClosure {
2921  private:
2922   bool _has_substitutions;
2923   Value simplify(Value v);
2924 
2925  public:
2926   PhiSimplifier(BlockBegin* start) : _has_substitutions(false) {
2927     start->iterate_preorder(this);
2928     if (_has_substitutions) {
2929       SubstitutionResolver sr(start);
2930     }
2931   }
2932   void block_do(BlockBegin* b);
2933   bool has_substitutions() const { return _has_substitutions; }
2934 };
2935 
2936 
2937 Value PhiSimplifier::simplify(Value v) {
2938   Phi* phi = v->as_Phi();
2939 
2940   if (phi == nullptr) {
2941     // no phi function
2942     return v;
2943   } else if (v->has_subst()) {
2944     // already substituted; subst can be phi itself -> simplify
2945     return simplify(v->subst());
2946   } else if (phi->is_set(Phi::cannot_simplify)) {
2947     // already tried to simplify phi before
2948     return phi;
2949   } else if (phi->is_set(Phi::visited)) {
2950     // break cycles in phi functions
2951     return phi;
2952   } else if (phi->type()->is_illegal()) {
2953     // illegal phi functions are ignored anyway
2954     return phi;
2955 
2956   } else {
2957     // mark phi function as processed to break cycles in phi functions
2958     phi->set(Phi::visited);
2959 
2960     // simplify x = [y, x] and x = [y, y] to y
2961     Value subst = nullptr;
2962     int opd_count = phi->operand_count();
2963     for (int i = 0; i < opd_count; i++) {
2964       Value opd = phi->operand_at(i);
2965       assert(opd != nullptr, "Operand must exist!");
2966 
2967       if (opd->type()->is_illegal()) {
2968         // if one operand is illegal, the entire phi function is illegal
2969         phi->make_illegal();
2970         phi->clear(Phi::visited);
2971         return phi;
2972       }
2973 
2974       Value new_opd = simplify(opd);
2975       assert(new_opd != nullptr, "Simplified operand must exist!");
2976 
2977       if (new_opd != phi && new_opd != subst) {
2978         if (subst == nullptr) {
2979           subst = new_opd;
2980         } else {
2981           // no simplification possible
2982           phi->set(Phi::cannot_simplify);
2983           phi->clear(Phi::visited);
2984           return phi;
2985         }
2986       }
2987     }
2988 
2989     // successfully simplified phi function
2990     assert(subst != nullptr, "illegal phi function");
2991     _has_substitutions = true;
2992     phi->clear(Phi::visited);
2993     phi->set_subst(subst);
2994 
2995 #ifndef PRODUCT
2996     if (PrintPhiFunctions) {
2997       tty->print_cr("simplified phi function %c%d to %c%d (Block B%d)", phi->type()->tchar(), phi->id(), subst->type()->tchar(), subst->id(), phi->block()->block_id());
2998     }
2999 #endif
3000 
3001     return subst;
3002   }
3003 }
3004 
3005 
3006 void PhiSimplifier::block_do(BlockBegin* b) {
3007   for_each_phi_fun(b, phi,
3008     simplify(phi);
3009   );
3010 
3011 #ifdef ASSERT
3012   for_each_phi_fun(b, phi,
3013                    assert(phi->operand_count() != 1 || phi->subst() != phi || phi->is_illegal(), "missed trivial simplification");
3014   );
3015 
3016   ValueStack* state = b->state()->caller_state();
3017   for_each_state_value(state, value,
3018     Phi* phi = value->as_Phi();
3019     assert(phi == nullptr || phi->block() != b, "must not have phi function to simplify in caller state");
3020   );
3021 #endif
3022 }
3023 
3024 // This method is called after all blocks are filled with HIR instructions
3025 // It eliminates all Phi functions of the form x = [y, y] and x = [y, x]
3026 void GraphBuilder::eliminate_redundant_phis(BlockBegin* start) {
3027   PhiSimplifier simplifier(start);
3028 }
3029 
3030 
3031 void GraphBuilder::connect_to_end(BlockBegin* beg) {
3032   // setup iteration
3033   kill_all();
3034   _block = beg;
3035   _state = beg->state()->copy_for_parsing();
3036   _last  = beg;
3037   iterate_bytecodes_for_block(beg->bci());
3038 }
3039 
3040 
3041 BlockEnd* GraphBuilder::iterate_bytecodes_for_block(int bci) {
3042 #ifndef PRODUCT
3043   if (PrintIRDuringConstruction) {
3044     tty->cr();
3045     InstructionPrinter ip;
3046     ip.print_instr(_block); tty->cr();
3047     ip.print_stack(_block->state()); tty->cr();
3048     ip.print_inline_level(_block);
3049     ip.print_head();
3050     tty->print_cr("locals size: %d stack size: %d", state()->locals_size(), state()->stack_size());
3051   }
3052 #endif
3053   _skip_block = false;
3054   assert(state() != nullptr, "ValueStack missing!");
3055   CompileLog* log = compilation()->log();
3056   ciBytecodeStream s(method());
3057   s.reset_to_bci(bci);
3058   int prev_bci = bci;
3059   scope_data()->set_stream(&s);
3060   // iterate
3061   Bytecodes::Code code = Bytecodes::_illegal;
3062   bool push_exception = false;
3063 
3064   if (block()->is_set(BlockBegin::exception_entry_flag) && block()->next() == nullptr) {
3065     // first thing in the exception entry block should be the exception object.
3066     push_exception = true;
3067   }
3068 
3069   bool ignore_return = scope_data()->ignore_return();
3070 
3071   while (!bailed_out() && last()->as_BlockEnd() == nullptr &&
3072          (code = stream()->next()) != ciBytecodeStream::EOBC() &&
3073          (block_at(s.cur_bci()) == nullptr || block_at(s.cur_bci()) == block())) {
3074     assert(state()->kind() == ValueStack::Parsing, "invalid state kind");
3075 
3076     if (log != nullptr)
3077       log->set_context("bc code='%d' bci='%d'", (int)code, s.cur_bci());
3078 
3079     // Check for active jsr during OSR compilation
3080     if (compilation()->is_osr_compile()
3081         && scope()->is_top_scope()
3082         && parsing_jsr()
3083         && s.cur_bci() == compilation()->osr_bci()) {
3084       bailout("OSR not supported while a jsr is active");
3085     }
3086 
3087     if (push_exception) {
3088       apush(append(new ExceptionObject()));
3089       push_exception = false;
3090     }
3091 
3092     // handle bytecode
3093     switch (code) {
3094       case Bytecodes::_nop            : /* nothing to do */ break;
3095       case Bytecodes::_aconst_null    : apush(append(new Constant(objectNull            ))); break;
3096       case Bytecodes::_iconst_m1      : ipush(append(new Constant(new IntConstant   (-1)))); break;
3097       case Bytecodes::_iconst_0       : ipush(append(new Constant(intZero               ))); break;
3098       case Bytecodes::_iconst_1       : ipush(append(new Constant(intOne                ))); break;
3099       case Bytecodes::_iconst_2       : ipush(append(new Constant(new IntConstant   ( 2)))); break;
3100       case Bytecodes::_iconst_3       : ipush(append(new Constant(new IntConstant   ( 3)))); break;
3101       case Bytecodes::_iconst_4       : ipush(append(new Constant(new IntConstant   ( 4)))); break;
3102       case Bytecodes::_iconst_5       : ipush(append(new Constant(new IntConstant   ( 5)))); break;
3103       case Bytecodes::_lconst_0       : lpush(append(new Constant(new LongConstant  ( 0)))); break;
3104       case Bytecodes::_lconst_1       : lpush(append(new Constant(new LongConstant  ( 1)))); break;
3105       case Bytecodes::_fconst_0       : fpush(append(new Constant(new FloatConstant ( 0)))); break;
3106       case Bytecodes::_fconst_1       : fpush(append(new Constant(new FloatConstant ( 1)))); break;
3107       case Bytecodes::_fconst_2       : fpush(append(new Constant(new FloatConstant ( 2)))); break;
3108       case Bytecodes::_dconst_0       : dpush(append(new Constant(new DoubleConstant( 0)))); break;
3109       case Bytecodes::_dconst_1       : dpush(append(new Constant(new DoubleConstant( 1)))); break;
3110       case Bytecodes::_bipush         : ipush(append(new Constant(new IntConstant(((signed char*)s.cur_bcp())[1])))); break;
3111       case Bytecodes::_sipush         : ipush(append(new Constant(new IntConstant((short)Bytes::get_Java_u2(s.cur_bcp()+1))))); break;
3112       case Bytecodes::_ldc            : // fall through
3113       case Bytecodes::_ldc_w          : // fall through
3114       case Bytecodes::_ldc2_w         : load_constant(); break;
3115       case Bytecodes::_iload          : load_local(intType     , s.get_index()); break;
3116       case Bytecodes::_lload          : load_local(longType    , s.get_index()); break;
3117       case Bytecodes::_fload          : load_local(floatType   , s.get_index()); break;
3118       case Bytecodes::_dload          : load_local(doubleType  , s.get_index()); break;
3119       case Bytecodes::_aload          : load_local(instanceType, s.get_index()); break;
3120       case Bytecodes::_iload_0        : load_local(intType   , 0); break;
3121       case Bytecodes::_iload_1        : load_local(intType   , 1); break;
3122       case Bytecodes::_iload_2        : load_local(intType   , 2); break;
3123       case Bytecodes::_iload_3        : load_local(intType   , 3); break;
3124       case Bytecodes::_lload_0        : load_local(longType  , 0); break;
3125       case Bytecodes::_lload_1        : load_local(longType  , 1); break;
3126       case Bytecodes::_lload_2        : load_local(longType  , 2); break;
3127       case Bytecodes::_lload_3        : load_local(longType  , 3); break;
3128       case Bytecodes::_fload_0        : load_local(floatType , 0); break;
3129       case Bytecodes::_fload_1        : load_local(floatType , 1); break;
3130       case Bytecodes::_fload_2        : load_local(floatType , 2); break;
3131       case Bytecodes::_fload_3        : load_local(floatType , 3); break;
3132       case Bytecodes::_dload_0        : load_local(doubleType, 0); break;
3133       case Bytecodes::_dload_1        : load_local(doubleType, 1); break;
3134       case Bytecodes::_dload_2        : load_local(doubleType, 2); break;
3135       case Bytecodes::_dload_3        : load_local(doubleType, 3); break;
3136       case Bytecodes::_aload_0        : load_local(objectType, 0); break;
3137       case Bytecodes::_aload_1        : load_local(objectType, 1); break;
3138       case Bytecodes::_aload_2        : load_local(objectType, 2); break;
3139       case Bytecodes::_aload_3        : load_local(objectType, 3); break;
3140       case Bytecodes::_iaload         : load_indexed(T_INT   ); break;
3141       case Bytecodes::_laload         : load_indexed(T_LONG  ); break;
3142       case Bytecodes::_faload         : load_indexed(T_FLOAT ); break;
3143       case Bytecodes::_daload         : load_indexed(T_DOUBLE); break;
3144       case Bytecodes::_aaload         : load_indexed(T_OBJECT); break;
3145       case Bytecodes::_baload         : load_indexed(T_BYTE  ); break;
3146       case Bytecodes::_caload         : load_indexed(T_CHAR  ); break;
3147       case Bytecodes::_saload         : load_indexed(T_SHORT ); break;
3148       case Bytecodes::_istore         : store_local(intType   , s.get_index()); break;
3149       case Bytecodes::_lstore         : store_local(longType  , s.get_index()); break;
3150       case Bytecodes::_fstore         : store_local(floatType , s.get_index()); break;
3151       case Bytecodes::_dstore         : store_local(doubleType, s.get_index()); break;
3152       case Bytecodes::_astore         : store_local(objectType, s.get_index()); break;
3153       case Bytecodes::_istore_0       : store_local(intType   , 0); break;
3154       case Bytecodes::_istore_1       : store_local(intType   , 1); break;
3155       case Bytecodes::_istore_2       : store_local(intType   , 2); break;
3156       case Bytecodes::_istore_3       : store_local(intType   , 3); break;
3157       case Bytecodes::_lstore_0       : store_local(longType  , 0); break;
3158       case Bytecodes::_lstore_1       : store_local(longType  , 1); break;
3159       case Bytecodes::_lstore_2       : store_local(longType  , 2); break;
3160       case Bytecodes::_lstore_3       : store_local(longType  , 3); break;
3161       case Bytecodes::_fstore_0       : store_local(floatType , 0); break;
3162       case Bytecodes::_fstore_1       : store_local(floatType , 1); break;
3163       case Bytecodes::_fstore_2       : store_local(floatType , 2); break;
3164       case Bytecodes::_fstore_3       : store_local(floatType , 3); break;
3165       case Bytecodes::_dstore_0       : store_local(doubleType, 0); break;
3166       case Bytecodes::_dstore_1       : store_local(doubleType, 1); break;
3167       case Bytecodes::_dstore_2       : store_local(doubleType, 2); break;
3168       case Bytecodes::_dstore_3       : store_local(doubleType, 3); break;
3169       case Bytecodes::_astore_0       : store_local(objectType, 0); break;
3170       case Bytecodes::_astore_1       : store_local(objectType, 1); break;
3171       case Bytecodes::_astore_2       : store_local(objectType, 2); break;
3172       case Bytecodes::_astore_3       : store_local(objectType, 3); break;
3173       case Bytecodes::_iastore        : store_indexed(T_INT   ); break;
3174       case Bytecodes::_lastore        : store_indexed(T_LONG  ); break;
3175       case Bytecodes::_fastore        : store_indexed(T_FLOAT ); break;
3176       case Bytecodes::_dastore        : store_indexed(T_DOUBLE); break;
3177       case Bytecodes::_aastore        : store_indexed(T_OBJECT); break;
3178       case Bytecodes::_bastore        : store_indexed(T_BYTE  ); break;
3179       case Bytecodes::_castore        : store_indexed(T_CHAR  ); break;
3180       case Bytecodes::_sastore        : store_indexed(T_SHORT ); break;
3181       case Bytecodes::_pop            : // fall through
3182       case Bytecodes::_pop2           : // fall through
3183       case Bytecodes::_dup            : // fall through
3184       case Bytecodes::_dup_x1         : // fall through
3185       case Bytecodes::_dup_x2         : // fall through
3186       case Bytecodes::_dup2           : // fall through
3187       case Bytecodes::_dup2_x1        : // fall through
3188       case Bytecodes::_dup2_x2        : // fall through
3189       case Bytecodes::_swap           : stack_op(code); break;
3190       case Bytecodes::_iadd           : arithmetic_op(intType   , code); break;
3191       case Bytecodes::_ladd           : arithmetic_op(longType  , code); break;
3192       case Bytecodes::_fadd           : arithmetic_op(floatType , code); break;
3193       case Bytecodes::_dadd           : arithmetic_op(doubleType, code); break;
3194       case Bytecodes::_isub           : arithmetic_op(intType   , code); break;
3195       case Bytecodes::_lsub           : arithmetic_op(longType  , code); break;
3196       case Bytecodes::_fsub           : arithmetic_op(floatType , code); break;
3197       case Bytecodes::_dsub           : arithmetic_op(doubleType, code); break;
3198       case Bytecodes::_imul           : arithmetic_op(intType   , code); break;
3199       case Bytecodes::_lmul           : arithmetic_op(longType  , code); break;
3200       case Bytecodes::_fmul           : arithmetic_op(floatType , code); break;
3201       case Bytecodes::_dmul           : arithmetic_op(doubleType, code); break;
3202       case Bytecodes::_idiv           : arithmetic_op(intType   , code, copy_state_for_exception()); break;
3203       case Bytecodes::_ldiv           : arithmetic_op(longType  , code, copy_state_for_exception()); break;
3204       case Bytecodes::_fdiv           : arithmetic_op(floatType , code); break;
3205       case Bytecodes::_ddiv           : arithmetic_op(doubleType, code); break;
3206       case Bytecodes::_irem           : arithmetic_op(intType   , code, copy_state_for_exception()); break;
3207       case Bytecodes::_lrem           : arithmetic_op(longType  , code, copy_state_for_exception()); break;
3208       case Bytecodes::_frem           : arithmetic_op(floatType , code); break;
3209       case Bytecodes::_drem           : arithmetic_op(doubleType, code); break;
3210       case Bytecodes::_ineg           : negate_op(intType   ); break;
3211       case Bytecodes::_lneg           : negate_op(longType  ); break;
3212       case Bytecodes::_fneg           : negate_op(floatType ); break;
3213       case Bytecodes::_dneg           : negate_op(doubleType); break;
3214       case Bytecodes::_ishl           : shift_op(intType , code); break;
3215       case Bytecodes::_lshl           : shift_op(longType, code); break;
3216       case Bytecodes::_ishr           : shift_op(intType , code); break;
3217       case Bytecodes::_lshr           : shift_op(longType, code); break;
3218       case Bytecodes::_iushr          : shift_op(intType , code); break;
3219       case Bytecodes::_lushr          : shift_op(longType, code); break;
3220       case Bytecodes::_iand           : logic_op(intType , code); break;
3221       case Bytecodes::_land           : logic_op(longType, code); break;
3222       case Bytecodes::_ior            : logic_op(intType , code); break;
3223       case Bytecodes::_lor            : logic_op(longType, code); break;
3224       case Bytecodes::_ixor           : logic_op(intType , code); break;
3225       case Bytecodes::_lxor           : logic_op(longType, code); break;
3226       case Bytecodes::_iinc           : increment(); break;
3227       case Bytecodes::_i2l            : convert(code, T_INT   , T_LONG  ); break;
3228       case Bytecodes::_i2f            : convert(code, T_INT   , T_FLOAT ); break;
3229       case Bytecodes::_i2d            : convert(code, T_INT   , T_DOUBLE); break;
3230       case Bytecodes::_l2i            : convert(code, T_LONG  , T_INT   ); break;
3231       case Bytecodes::_l2f            : convert(code, T_LONG  , T_FLOAT ); break;
3232       case Bytecodes::_l2d            : convert(code, T_LONG  , T_DOUBLE); break;
3233       case Bytecodes::_f2i            : convert(code, T_FLOAT , T_INT   ); break;
3234       case Bytecodes::_f2l            : convert(code, T_FLOAT , T_LONG  ); break;
3235       case Bytecodes::_f2d            : convert(code, T_FLOAT , T_DOUBLE); break;
3236       case Bytecodes::_d2i            : convert(code, T_DOUBLE, T_INT   ); break;
3237       case Bytecodes::_d2l            : convert(code, T_DOUBLE, T_LONG  ); break;
3238       case Bytecodes::_d2f            : convert(code, T_DOUBLE, T_FLOAT ); break;
3239       case Bytecodes::_i2b            : convert(code, T_INT   , T_BYTE  ); break;
3240       case Bytecodes::_i2c            : convert(code, T_INT   , T_CHAR  ); break;
3241       case Bytecodes::_i2s            : convert(code, T_INT   , T_SHORT ); break;
3242       case Bytecodes::_lcmp           : compare_op(longType  , code); break;
3243       case Bytecodes::_fcmpl          : compare_op(floatType , code); break;
3244       case Bytecodes::_fcmpg          : compare_op(floatType , code); break;
3245       case Bytecodes::_dcmpl          : compare_op(doubleType, code); break;
3246       case Bytecodes::_dcmpg          : compare_op(doubleType, code); break;
3247       case Bytecodes::_ifeq           : if_zero(intType   , If::eql); break;
3248       case Bytecodes::_ifne           : if_zero(intType   , If::neq); break;
3249       case Bytecodes::_iflt           : if_zero(intType   , If::lss); break;
3250       case Bytecodes::_ifge           : if_zero(intType   , If::geq); break;
3251       case Bytecodes::_ifgt           : if_zero(intType   , If::gtr); break;
3252       case Bytecodes::_ifle           : if_zero(intType   , If::leq); break;
3253       case Bytecodes::_if_icmpeq      : if_same(intType   , If::eql); break;
3254       case Bytecodes::_if_icmpne      : if_same(intType   , If::neq); break;
3255       case Bytecodes::_if_icmplt      : if_same(intType   , If::lss); break;
3256       case Bytecodes::_if_icmpge      : if_same(intType   , If::geq); break;
3257       case Bytecodes::_if_icmpgt      : if_same(intType   , If::gtr); break;
3258       case Bytecodes::_if_icmple      : if_same(intType   , If::leq); break;
3259       case Bytecodes::_if_acmpeq      : if_same(objectType, If::eql); break;
3260       case Bytecodes::_if_acmpne      : if_same(objectType, If::neq); break;
3261       case Bytecodes::_goto           : _goto(s.cur_bci(), s.get_dest()); break;
3262       case Bytecodes::_jsr            : jsr(s.get_dest()); break;
3263       case Bytecodes::_ret            : ret(s.get_index()); break;
3264       case Bytecodes::_tableswitch    : table_switch(); break;
3265       case Bytecodes::_lookupswitch   : lookup_switch(); break;
3266       case Bytecodes::_ireturn        : method_return(ipop(), ignore_return); break;
3267       case Bytecodes::_lreturn        : method_return(lpop(), ignore_return); break;
3268       case Bytecodes::_freturn        : method_return(fpop(), ignore_return); break;
3269       case Bytecodes::_dreturn        : method_return(dpop(), ignore_return); break;
3270       case Bytecodes::_areturn        : method_return(apop(), ignore_return); break;
3271       case Bytecodes::_return         : method_return(nullptr, ignore_return); break;
3272       case Bytecodes::_getstatic      : // fall through
3273       case Bytecodes::_putstatic      : // fall through
3274       case Bytecodes::_getfield       : // fall through
3275       case Bytecodes::_putfield       : access_field(code); break;
3276       case Bytecodes::_invokevirtual  : // fall through
3277       case Bytecodes::_invokespecial  : // fall through
3278       case Bytecodes::_invokestatic   : // fall through
3279       case Bytecodes::_invokedynamic  : // fall through
3280       case Bytecodes::_invokeinterface: invoke(code); break;
3281       case Bytecodes::_new            : new_instance(s.get_index_u2()); break;
3282       case Bytecodes::_newarray       : new_type_array(); break;
3283       case Bytecodes::_anewarray      : new_object_array(); break;
3284       case Bytecodes::_arraylength    : { ValueStack* state_before = copy_state_for_exception(); ipush(append(new ArrayLength(apop(), state_before))); break; }
3285       case Bytecodes::_athrow         : throw_op(s.cur_bci()); break;
3286       case Bytecodes::_checkcast      : check_cast(s.get_index_u2()); break;
3287       case Bytecodes::_instanceof     : instance_of(s.get_index_u2()); break;
3288       case Bytecodes::_monitorenter   : monitorenter(apop(), s.cur_bci()); break;
3289       case Bytecodes::_monitorexit    : monitorexit (apop(), s.cur_bci()); break;
3290       case Bytecodes::_wide           : ShouldNotReachHere(); break;
3291       case Bytecodes::_multianewarray : new_multi_array(s.cur_bcp()[3]); break;
3292       case Bytecodes::_ifnull         : if_null(objectType, If::eql); break;
3293       case Bytecodes::_ifnonnull      : if_null(objectType, If::neq); break;
3294       case Bytecodes::_goto_w         : _goto(s.cur_bci(), s.get_far_dest()); break;
3295       case Bytecodes::_jsr_w          : jsr(s.get_far_dest()); break;
3296       case Bytecodes::_breakpoint     : BAILOUT_("concurrent setting of breakpoint", nullptr);
3297       default                         : ShouldNotReachHere(); break;
3298     }
3299 
3300     if (log != nullptr)
3301       log->clear_context(); // skip marker if nothing was printed
3302 
3303     // save current bci to setup Goto at the end
3304     prev_bci = s.cur_bci();
3305 
3306   }
3307   CHECK_BAILOUT_(nullptr);
3308   // stop processing of this block (see try_inline_full)
3309   if (_skip_block) {
3310     _skip_block = false;
3311     assert(_last && _last->as_BlockEnd(), "");
3312     return _last->as_BlockEnd();
3313   }
3314   // if there are any, check if last instruction is a BlockEnd instruction
3315   BlockEnd* end = last()->as_BlockEnd();
3316   if (end == nullptr) {
3317     // all blocks must end with a BlockEnd instruction => add a Goto
3318     end = new Goto(block_at(s.cur_bci()), false);
3319     append(end);
3320   }
3321   assert(end == last()->as_BlockEnd(), "inconsistency");
3322 
3323   assert(end->state() != nullptr, "state must already be present");
3324   assert(end->as_Return() == nullptr || end->as_Throw() == nullptr || end->state()->stack_size() == 0, "stack not needed for return and throw");
3325 
3326   // connect to begin & set state
3327   // NOTE that inlining may have changed the block we are parsing
3328   block()->set_end(end);
3329   // propagate state
3330   for (int i = end->number_of_sux() - 1; i >= 0; i--) {
3331     BlockBegin* sux = end->sux_at(i);
3332     assert(sux->is_predecessor(block()), "predecessor missing");
3333     // be careful, bailout if bytecodes are strange
3334     if (!sux->try_merge(end->state(), compilation()->has_irreducible_loops())) BAILOUT_("block join failed", nullptr);
3335     scope_data()->add_to_work_list(end->sux_at(i));
3336   }
3337 
3338   scope_data()->set_stream(nullptr);
3339 
3340   // done
3341   return end;
3342 }
3343 
3344 
3345 void GraphBuilder::iterate_all_blocks(bool start_in_current_block_for_inlining) {
3346   do {
3347     if (start_in_current_block_for_inlining && !bailed_out()) {
3348       iterate_bytecodes_for_block(0);
3349       start_in_current_block_for_inlining = false;
3350     } else {
3351       BlockBegin* b;
3352       while ((b = scope_data()->remove_from_work_list()) != nullptr) {
3353         if (!b->is_set(BlockBegin::was_visited_flag)) {
3354           if (b->is_set(BlockBegin::osr_entry_flag)) {
3355             // we're about to parse the osr entry block, so make sure
3356             // we setup the OSR edge leading into this block so that
3357             // Phis get setup correctly.
3358             setup_osr_entry_block();
3359             // this is no longer the osr entry block, so clear it.
3360             b->clear(BlockBegin::osr_entry_flag);
3361           }
3362           b->set(BlockBegin::was_visited_flag);
3363           connect_to_end(b);
3364         }
3365       }
3366     }
3367   } while (!bailed_out() && !scope_data()->is_work_list_empty());
3368 }
3369 
3370 
3371 bool GraphBuilder::_can_trap      [Bytecodes::number_of_java_codes];
3372 
3373 void GraphBuilder::initialize() {
3374   // the following bytecodes are assumed to potentially
3375   // throw exceptions in compiled code - note that e.g.
3376   // monitorexit & the return bytecodes do not throw
3377   // exceptions since monitor pairing proved that they
3378   // succeed (if monitor pairing succeeded)
3379   Bytecodes::Code can_trap_list[] =
3380     { Bytecodes::_ldc
3381     , Bytecodes::_ldc_w
3382     , Bytecodes::_ldc2_w
3383     , Bytecodes::_iaload
3384     , Bytecodes::_laload
3385     , Bytecodes::_faload
3386     , Bytecodes::_daload
3387     , Bytecodes::_aaload
3388     , Bytecodes::_baload
3389     , Bytecodes::_caload
3390     , Bytecodes::_saload
3391     , Bytecodes::_iastore
3392     , Bytecodes::_lastore
3393     , Bytecodes::_fastore
3394     , Bytecodes::_dastore
3395     , Bytecodes::_aastore
3396     , Bytecodes::_bastore
3397     , Bytecodes::_castore
3398     , Bytecodes::_sastore
3399     , Bytecodes::_idiv
3400     , Bytecodes::_ldiv
3401     , Bytecodes::_irem
3402     , Bytecodes::_lrem
3403     , Bytecodes::_getstatic
3404     , Bytecodes::_putstatic
3405     , Bytecodes::_getfield
3406     , Bytecodes::_putfield
3407     , Bytecodes::_invokevirtual
3408     , Bytecodes::_invokespecial
3409     , Bytecodes::_invokestatic
3410     , Bytecodes::_invokedynamic
3411     , Bytecodes::_invokeinterface
3412     , Bytecodes::_new
3413     , Bytecodes::_newarray
3414     , Bytecodes::_anewarray
3415     , Bytecodes::_arraylength
3416     , Bytecodes::_athrow
3417     , Bytecodes::_checkcast
3418     , Bytecodes::_instanceof
3419     , Bytecodes::_monitorenter
3420     , Bytecodes::_multianewarray
3421     };
3422 
3423   // inititialize trap tables
3424   for (int i = 0; i < Bytecodes::number_of_java_codes; i++) {
3425     _can_trap[i] = false;
3426   }
3427   // set standard trap info
3428   for (uint j = 0; j < ARRAY_SIZE(can_trap_list); j++) {
3429     _can_trap[can_trap_list[j]] = true;
3430   }
3431 }
3432 
3433 
3434 BlockBegin* GraphBuilder::header_block(BlockBegin* entry, BlockBegin::Flag f, ValueStack* state) {
3435   assert(entry->is_set(f), "entry/flag mismatch");
3436   // create header block
3437   BlockBegin* h = new BlockBegin(entry->bci());
3438   h->set_depth_first_number(0);
3439 
3440   Value l = h;
3441   BlockEnd* g = new Goto(entry, false);
3442   l->set_next(g, entry->bci());
3443   h->set_end(g);
3444   h->set(f);
3445   // setup header block end state
3446   ValueStack* s = state->copy(ValueStack::StateAfter, entry->bci()); // can use copy since stack is empty (=> no phis)
3447   assert(s->stack_is_empty(), "must have empty stack at entry point");
3448   g->set_state(s);
3449   return h;
3450 }
3451 
3452 
3453 
3454 BlockBegin* GraphBuilder::setup_start_block(int osr_bci, BlockBegin* std_entry, BlockBegin* osr_entry, ValueStack* state) {
3455   BlockBegin* start = new BlockBegin(0);
3456 
3457   // This code eliminates the empty start block at the beginning of
3458   // each method.  Previously, each method started with the
3459   // start-block created below, and this block was followed by the
3460   // header block that was always empty.  This header block is only
3461   // necessary if std_entry is also a backward branch target because
3462   // then phi functions may be necessary in the header block.  It's
3463   // also necessary when profiling so that there's a single block that
3464   // can increment the counters.
3465   // In addition, with range check elimination, we may need a valid block
3466   // that dominates all the rest to insert range predicates.
3467   BlockBegin* new_header_block;
3468   if (std_entry->number_of_preds() > 0 || is_profiling() || RangeCheckElimination) {
3469     new_header_block = header_block(std_entry, BlockBegin::std_entry_flag, state);
3470   } else {
3471     new_header_block = std_entry;
3472   }
3473 
3474   // setup start block (root for the IR graph)
3475   Base* base =
3476     new Base(
3477       new_header_block,
3478       osr_entry
3479     );
3480   start->set_next(base, 0);
3481   start->set_end(base);
3482   // create & setup state for start block
3483   start->set_state(state->copy(ValueStack::StateAfter, std_entry->bci()));
3484   base->set_state(state->copy(ValueStack::StateAfter, std_entry->bci()));
3485 
3486   if (base->std_entry()->state() == nullptr) {
3487     // setup states for header blocks
3488     base->std_entry()->merge(state, compilation()->has_irreducible_loops());
3489   }
3490 
3491   assert(base->std_entry()->state() != nullptr, "");
3492   return start;
3493 }
3494 
3495 
3496 void GraphBuilder::setup_osr_entry_block() {
3497   assert(compilation()->is_osr_compile(), "only for osrs");
3498 
3499   int osr_bci = compilation()->osr_bci();
3500   ciBytecodeStream s(method());
3501   s.reset_to_bci(osr_bci);
3502   s.next();
3503   scope_data()->set_stream(&s);
3504 
3505   // create a new block to be the osr setup code
3506   _osr_entry = new BlockBegin(osr_bci);
3507   _osr_entry->set(BlockBegin::osr_entry_flag);
3508   _osr_entry->set_depth_first_number(0);
3509   BlockBegin* target = bci2block()->at(osr_bci);
3510   assert(target != nullptr && target->is_set(BlockBegin::osr_entry_flag), "must be there");
3511   // the osr entry has no values for locals
3512   ValueStack* state = target->state()->copy();
3513   _osr_entry->set_state(state);
3514 
3515   kill_all();
3516   _block = _osr_entry;
3517   _state = _osr_entry->state()->copy();
3518   assert(_state->bci() == osr_bci, "mismatch");
3519   _last  = _osr_entry;
3520   Value e = append(new OsrEntry());
3521   e->set_needs_null_check(false);
3522 
3523   // OSR buffer is
3524   //
3525   // locals[nlocals-1..0]
3526   // monitors[number_of_locks-1..0]
3527   //
3528   // locals is a direct copy of the interpreter frame so in the osr buffer
3529   // so first slot in the local array is the last local from the interpreter
3530   // and last slot is local[0] (receiver) from the interpreter
3531   //
3532   // Similarly with locks. The first lock slot in the osr buffer is the nth lock
3533   // from the interpreter frame, the nth lock slot in the osr buffer is 0th lock
3534   // in the interpreter frame (the method lock if a sync method)
3535 
3536   // Initialize monitors in the compiled activation.
3537 
3538   int index;
3539   Value local;
3540 
3541   // find all the locals that the interpreter thinks contain live oops
3542   const ResourceBitMap live_oops = method()->live_local_oops_at_bci(osr_bci);
3543 
3544   // compute the offset into the locals so that we can treat the buffer
3545   // as if the locals were still in the interpreter frame
3546   int locals_offset = BytesPerWord * (method()->max_locals() - 1);
3547   for_each_local_value(state, index, local) {
3548     int offset = locals_offset - (index + local->type()->size() - 1) * BytesPerWord;
3549     Value get;
3550     if (local->type()->is_object_kind() && !live_oops.at(index)) {
3551       // The interpreter thinks this local is dead but the compiler
3552       // doesn't so pretend that the interpreter passed in null.
3553       get = append(new Constant(objectNull));
3554     } else {
3555       Value off_val = append(new Constant(new IntConstant(offset)));
3556       get = append(new UnsafeGet(as_BasicType(local->type()), e,
3557                                  off_val,
3558                                  false/*is_volatile*/,
3559                                  true/*is_raw*/));
3560     }
3561     _state->store_local(index, get);
3562   }
3563 
3564   // the storage for the OSR buffer is freed manually in the LIRGenerator.
3565 
3566   assert(state->caller_state() == nullptr, "should be top scope");
3567   state->clear_locals();
3568   Goto* g = new Goto(target, false);
3569   append(g);
3570   _osr_entry->set_end(g);
3571   target->merge(_osr_entry->end()->state(), compilation()->has_irreducible_loops());
3572 
3573   scope_data()->set_stream(nullptr);
3574 }
3575 
3576 
3577 ValueStack* GraphBuilder::state_at_entry() {
3578   ValueStack* state = new ValueStack(scope(), nullptr);
3579 
3580   // Set up locals for receiver
3581   int idx = 0;
3582   if (!method()->is_static()) {
3583     // we should always see the receiver
3584     state->store_local(idx, new Local(method()->holder(), objectType, idx,
3585              /*receiver*/ true, /*null_free*/ method()->holder()->is_flat_array_klass()));
3586     idx = 1;
3587   }
3588 
3589   // Set up locals for incoming arguments
3590   ciSignature* sig = method()->signature();
3591   for (int i = 0; i < sig->count(); i++) {
3592     ciType* type = sig->type_at(i);
3593     BasicType basic_type = type->basic_type();
3594     // don't allow T_ARRAY to propagate into locals types
3595     if (is_reference_type(basic_type)) basic_type = T_OBJECT;
3596     ValueType* vt = as_ValueType(basic_type);
3597     state->store_local(idx, new Local(type, vt, idx, false, false));
3598     idx += type->size();
3599   }
3600 
3601   // lock synchronized method
3602   if (method()->is_synchronized()) {
3603     state->lock(nullptr);
3604   }
3605 
3606   return state;
3607 }
3608 
3609 
3610 GraphBuilder::GraphBuilder(Compilation* compilation, IRScope* scope)
3611   : _scope_data(nullptr)
3612   , _compilation(compilation)
3613   , _memory(new MemoryBuffer())
3614   , _inline_bailout_msg(nullptr)
3615   , _instruction_count(0)
3616   , _osr_entry(nullptr)
3617   , _pending_field_access(nullptr)
3618   , _pending_load_indexed(nullptr)
3619 {
3620   int osr_bci = compilation->osr_bci();
3621 
3622   // determine entry points and bci2block mapping
3623   BlockListBuilder blm(compilation, scope, osr_bci);
3624   CHECK_BAILOUT();
3625 
3626   BlockList* bci2block = blm.bci2block();
3627   BlockBegin* start_block = bci2block->at(0);
3628 
3629   push_root_scope(scope, bci2block, start_block);
3630 
3631   // setup state for std entry
3632   _initial_state = state_at_entry();
3633   start_block->merge(_initial_state, compilation->has_irreducible_loops());
3634 
3635   // End nulls still exist here
3636 
3637   // complete graph
3638   _vmap        = new ValueMap();
3639   switch (scope->method()->intrinsic_id()) {
3640   case vmIntrinsics::_dabs          : // fall through
3641   case vmIntrinsics::_dsqrt         : // fall through
3642   case vmIntrinsics::_dsqrt_strict  : // fall through
3643   case vmIntrinsics::_dsin          : // fall through
3644   case vmIntrinsics::_dcos          : // fall through
3645   case vmIntrinsics::_dtan          : // fall through
3646   case vmIntrinsics::_dtanh         : // fall through
3647   case vmIntrinsics::_dlog          : // fall through
3648   case vmIntrinsics::_dlog10        : // fall through
3649   case vmIntrinsics::_dexp          : // fall through
3650   case vmIntrinsics::_dpow          : // fall through
3651     {
3652       // Compiles where the root method is an intrinsic need a special
3653       // compilation environment because the bytecodes for the method
3654       // shouldn't be parsed during the compilation, only the special
3655       // Intrinsic node should be emitted.  If this isn't done the
3656       // code for the inlined version will be different than the root
3657       // compiled version which could lead to monotonicity problems on
3658       // intel.
3659       if (CheckIntrinsics && !scope->method()->intrinsic_candidate()) {
3660         BAILOUT("failed to inline intrinsic, method not annotated");
3661       }
3662 
3663       // Set up a stream so that appending instructions works properly.
3664       ciBytecodeStream s(scope->method());
3665       s.reset_to_bci(0);
3666       scope_data()->set_stream(&s);
3667       s.next();
3668 
3669       // setup the initial block state
3670       _block = start_block;
3671       _state = start_block->state()->copy_for_parsing();
3672       _last  = start_block;
3673       load_local(doubleType, 0);
3674       if (scope->method()->intrinsic_id() == vmIntrinsics::_dpow) {
3675         load_local(doubleType, 2);
3676       }
3677 
3678       // Emit the intrinsic node.
3679       bool result = try_inline_intrinsics(scope->method());
3680       if (!result) BAILOUT("failed to inline intrinsic");
3681       method_return(dpop());
3682 
3683       // connect the begin and end blocks and we're all done.
3684       BlockEnd* end = last()->as_BlockEnd();
3685       block()->set_end(end);
3686       break;
3687     }
3688 
3689   case vmIntrinsics::_Reference_get:
3690     {
3691       {
3692         // With java.lang.ref.reference.get() we must go through the
3693         // intrinsic - when G1 is enabled - even when get() is the root
3694         // method of the compile so that, if necessary, the value in
3695         // the referent field of the reference object gets recorded by
3696         // the pre-barrier code.
3697         // Specifically, if G1 is enabled, the value in the referent
3698         // field is recorded by the G1 SATB pre barrier. This will
3699         // result in the referent being marked live and the reference
3700         // object removed from the list of discovered references during
3701         // reference processing.
3702         if (CheckIntrinsics && !scope->method()->intrinsic_candidate()) {
3703           BAILOUT("failed to inline intrinsic, method not annotated");
3704         }
3705 
3706         // Also we need intrinsic to prevent commoning reads from this field
3707         // across safepoint since GC can change its value.
3708 
3709         // Set up a stream so that appending instructions works properly.
3710         ciBytecodeStream s(scope->method());
3711         s.reset_to_bci(0);
3712         scope_data()->set_stream(&s);
3713         s.next();
3714 
3715         // setup the initial block state
3716         _block = start_block;
3717         _state = start_block->state()->copy_for_parsing();
3718         _last  = start_block;
3719         load_local(objectType, 0);
3720 
3721         // Emit the intrinsic node.
3722         bool result = try_inline_intrinsics(scope->method());
3723         if (!result) BAILOUT("failed to inline intrinsic");
3724         method_return(apop());
3725 
3726         // connect the begin and end blocks and we're all done.
3727         BlockEnd* end = last()->as_BlockEnd();
3728         block()->set_end(end);
3729         break;
3730       }
3731       // Otherwise, fall thru
3732     }
3733 
3734   default:
3735     scope_data()->add_to_work_list(start_block);
3736     iterate_all_blocks();
3737     break;
3738   }
3739   CHECK_BAILOUT();
3740 
3741 # ifdef ASSERT
3742   // For all blocks reachable from start_block: _end must be non-null
3743   {
3744     BlockList processed;
3745     BlockList to_go;
3746     to_go.append(start_block);
3747     while(to_go.length() > 0) {
3748       BlockBegin* current = to_go.pop();
3749       assert(current != nullptr, "Should not happen.");
3750       assert(current->end() != nullptr, "All blocks reachable from start_block should have end() != nullptr.");
3751       processed.append(current);
3752       for(int i = 0; i < current->number_of_sux(); i++) {
3753         BlockBegin* s = current->sux_at(i);
3754         if (!processed.contains(s)) {
3755           to_go.append(s);
3756         }
3757       }
3758     }
3759   }
3760 #endif // ASSERT
3761 
3762   _start = setup_start_block(osr_bci, start_block, _osr_entry, _initial_state);
3763 
3764   eliminate_redundant_phis(_start);
3765 
3766   NOT_PRODUCT(if (PrintValueNumbering && Verbose) print_stats());
3767   // for osr compile, bailout if some requirements are not fulfilled
3768   if (osr_bci != -1) {
3769     BlockBegin* osr_block = blm.bci2block()->at(osr_bci);
3770     if (!osr_block->is_set(BlockBegin::was_visited_flag)) {
3771       BAILOUT("osr entry must have been visited for osr compile");
3772     }
3773 
3774     // check if osr entry point has empty stack - we cannot handle non-empty stacks at osr entry points
3775     if (!osr_block->state()->stack_is_empty()) {
3776       BAILOUT("stack not empty at OSR entry point");
3777     }
3778   }
3779 #ifndef PRODUCT
3780   if (PrintCompilation && Verbose) tty->print_cr("Created %d Instructions", _instruction_count);
3781 #endif
3782 }
3783 
3784 
3785 ValueStack* GraphBuilder::copy_state_before() {
3786   return copy_state_before_with_bci(bci());
3787 }
3788 
3789 ValueStack* GraphBuilder::copy_state_exhandling() {
3790   return copy_state_exhandling_with_bci(bci());
3791 }
3792 
3793 ValueStack* GraphBuilder::copy_state_for_exception() {
3794   return copy_state_for_exception_with_bci(bci());
3795 }
3796 
3797 ValueStack* GraphBuilder::copy_state_before_with_bci(int bci) {
3798   return state()->copy(ValueStack::StateBefore, bci);
3799 }
3800 
3801 ValueStack* GraphBuilder::copy_state_exhandling_with_bci(int bci) {
3802   if (!has_handler()) return nullptr;
3803   return state()->copy(ValueStack::StateBefore, bci);
3804 }
3805 
3806 ValueStack* GraphBuilder::copy_state_for_exception_with_bci(int bci) {
3807   ValueStack* s = copy_state_exhandling_with_bci(bci);
3808   if (s == nullptr) {
3809     // no handler, no need to retain locals
3810     ValueStack::Kind exc_kind = ValueStack::empty_exception_kind();
3811     s = state()->copy(exc_kind, bci);
3812   }
3813   return s;
3814 }
3815 
3816 int GraphBuilder::recursive_inline_level(ciMethod* cur_callee) const {
3817   int recur_level = 0;
3818   for (IRScope* s = scope(); s != nullptr; s = s->caller()) {
3819     if (s->method() == cur_callee) {
3820       ++recur_level;
3821     }
3822   }
3823   return recur_level;
3824 }
3825 
3826 static void set_flags_for_inlined_callee(Compilation* compilation, ciMethod* callee) {
3827   if (callee->has_reserved_stack_access()) {
3828     compilation->set_has_reserved_stack_access(true);
3829   }
3830   if (callee->is_synchronized() || callee->has_monitor_bytecodes()) {
3831     compilation->set_has_monitors(true);
3832   }
3833   if (callee->is_scoped()) {
3834     compilation->set_has_scoped_access(true);
3835   }
3836 }
3837 
3838 bool GraphBuilder::try_inline(ciMethod* callee, bool holder_known, bool ignore_return, Bytecodes::Code bc, Value receiver) {
3839   const char* msg = nullptr;
3840 
3841   // clear out any existing inline bailout condition
3842   clear_inline_bailout();
3843 
3844   // exclude methods we don't want to inline
3845   msg = should_not_inline(callee);
3846   if (msg != nullptr) {
3847     print_inlining(callee, msg, /*success*/ false);
3848     return false;
3849   }
3850 
3851   // method handle invokes
3852   if (callee->is_method_handle_intrinsic()) {
3853     if (try_method_handle_inline(callee, ignore_return)) {
3854       set_flags_for_inlined_callee(compilation(), callee);
3855       return true;
3856     }
3857     return false;
3858   }
3859 
3860   // handle intrinsics
3861   if (callee->intrinsic_id() != vmIntrinsics::_none &&
3862       callee->check_intrinsic_candidate()) {
3863     if (try_inline_intrinsics(callee, ignore_return)) {
3864       print_inlining(callee, "intrinsic");
3865       set_flags_for_inlined_callee(compilation(), callee);
3866       return true;
3867     }
3868     // try normal inlining
3869   }
3870 
3871   // certain methods cannot be parsed at all
3872   msg = check_can_parse(callee);
3873   if (msg != nullptr) {
3874     print_inlining(callee, msg, /*success*/ false);
3875     return false;
3876   }
3877 
3878   // If bytecode not set use the current one.
3879   if (bc == Bytecodes::_illegal) {
3880     bc = code();
3881   }
3882   if (try_inline_full(callee, holder_known, ignore_return, bc, receiver)) {
3883     set_flags_for_inlined_callee(compilation(), callee);
3884     return true;
3885   }
3886 
3887   // Entire compilation could fail during try_inline_full call.
3888   // In that case printing inlining decision info is useless.
3889   if (!bailed_out())
3890     print_inlining(callee, _inline_bailout_msg, /*success*/ false);
3891 
3892   return false;
3893 }
3894 
3895 
3896 const char* GraphBuilder::check_can_parse(ciMethod* callee) const {
3897   // Certain methods cannot be parsed at all:
3898   if ( callee->is_native())            return "native method";
3899   if ( callee->is_abstract())          return "abstract method";
3900   if (!callee->can_be_parsed())        return "cannot be parsed";
3901   return nullptr;
3902 }
3903 
3904 // negative filter: should callee NOT be inlined?  returns null, ok to inline, or rejection msg
3905 const char* GraphBuilder::should_not_inline(ciMethod* callee) const {
3906   if ( compilation()->directive()->should_not_inline(callee)) return "disallowed by CompileCommand";
3907   if ( callee->dont_inline())          return "don't inline by annotation";
3908   return nullptr;
3909 }
3910 
3911 void GraphBuilder::build_graph_for_intrinsic(ciMethod* callee, bool ignore_return) {
3912   vmIntrinsics::ID id = callee->intrinsic_id();
3913   assert(id != vmIntrinsics::_none, "must be a VM intrinsic");
3914 
3915   // Some intrinsics need special IR nodes.
3916   switch(id) {
3917   case vmIntrinsics::_getReference           : append_unsafe_get(callee, T_OBJECT,  false); return;
3918   case vmIntrinsics::_getBoolean             : append_unsafe_get(callee, T_BOOLEAN, false); return;
3919   case vmIntrinsics::_getByte                : append_unsafe_get(callee, T_BYTE,    false); return;
3920   case vmIntrinsics::_getShort               : append_unsafe_get(callee, T_SHORT,   false); return;
3921   case vmIntrinsics::_getChar                : append_unsafe_get(callee, T_CHAR,    false); return;
3922   case vmIntrinsics::_getInt                 : append_unsafe_get(callee, T_INT,     false); return;
3923   case vmIntrinsics::_getLong                : append_unsafe_get(callee, T_LONG,    false); return;
3924   case vmIntrinsics::_getFloat               : append_unsafe_get(callee, T_FLOAT,   false); return;
3925   case vmIntrinsics::_getDouble              : append_unsafe_get(callee, T_DOUBLE,  false); return;
3926   case vmIntrinsics::_putReference           : append_unsafe_put(callee, T_OBJECT,  false); return;
3927   case vmIntrinsics::_putBoolean             : append_unsafe_put(callee, T_BOOLEAN, false); return;
3928   case vmIntrinsics::_putByte                : append_unsafe_put(callee, T_BYTE,    false); return;
3929   case vmIntrinsics::_putShort               : append_unsafe_put(callee, T_SHORT,   false); return;
3930   case vmIntrinsics::_putChar                : append_unsafe_put(callee, T_CHAR,    false); return;
3931   case vmIntrinsics::_putInt                 : append_unsafe_put(callee, T_INT,     false); return;
3932   case vmIntrinsics::_putLong                : append_unsafe_put(callee, T_LONG,    false); return;
3933   case vmIntrinsics::_putFloat               : append_unsafe_put(callee, T_FLOAT,   false); return;
3934   case vmIntrinsics::_putDouble              : append_unsafe_put(callee, T_DOUBLE,  false); return;
3935   case vmIntrinsics::_getShortUnaligned      : append_unsafe_get(callee, T_SHORT,   false); return;
3936   case vmIntrinsics::_getCharUnaligned       : append_unsafe_get(callee, T_CHAR,    false); return;
3937   case vmIntrinsics::_getIntUnaligned        : append_unsafe_get(callee, T_INT,     false); return;
3938   case vmIntrinsics::_getLongUnaligned       : append_unsafe_get(callee, T_LONG,    false); return;
3939   case vmIntrinsics::_putShortUnaligned      : append_unsafe_put(callee, T_SHORT,   false); return;
3940   case vmIntrinsics::_putCharUnaligned       : append_unsafe_put(callee, T_CHAR,    false); return;
3941   case vmIntrinsics::_putIntUnaligned        : append_unsafe_put(callee, T_INT,     false); return;
3942   case vmIntrinsics::_putLongUnaligned       : append_unsafe_put(callee, T_LONG,    false); return;
3943   case vmIntrinsics::_getReferenceVolatile   : append_unsafe_get(callee, T_OBJECT,  true); return;
3944   case vmIntrinsics::_getBooleanVolatile     : append_unsafe_get(callee, T_BOOLEAN, true); return;
3945   case vmIntrinsics::_getByteVolatile        : append_unsafe_get(callee, T_BYTE,    true); return;
3946   case vmIntrinsics::_getShortVolatile       : append_unsafe_get(callee, T_SHORT,   true); return;
3947   case vmIntrinsics::_getCharVolatile        : append_unsafe_get(callee, T_CHAR,    true); return;
3948   case vmIntrinsics::_getIntVolatile         : append_unsafe_get(callee, T_INT,     true); return;
3949   case vmIntrinsics::_getLongVolatile        : append_unsafe_get(callee, T_LONG,    true); return;
3950   case vmIntrinsics::_getFloatVolatile       : append_unsafe_get(callee, T_FLOAT,   true); return;
3951   case vmIntrinsics::_getDoubleVolatile      : append_unsafe_get(callee, T_DOUBLE,  true); return;
3952   case vmIntrinsics::_putReferenceVolatile   : append_unsafe_put(callee, T_OBJECT,  true); return;
3953   case vmIntrinsics::_putBooleanVolatile     : append_unsafe_put(callee, T_BOOLEAN, true); return;
3954   case vmIntrinsics::_putByteVolatile        : append_unsafe_put(callee, T_BYTE,    true); return;
3955   case vmIntrinsics::_putShortVolatile       : append_unsafe_put(callee, T_SHORT,   true); return;
3956   case vmIntrinsics::_putCharVolatile        : append_unsafe_put(callee, T_CHAR,    true); return;
3957   case vmIntrinsics::_putIntVolatile         : append_unsafe_put(callee, T_INT,     true); return;
3958   case vmIntrinsics::_putLongVolatile        : append_unsafe_put(callee, T_LONG,    true); return;
3959   case vmIntrinsics::_putFloatVolatile       : append_unsafe_put(callee, T_FLOAT,   true); return;
3960   case vmIntrinsics::_putDoubleVolatile      : append_unsafe_put(callee, T_DOUBLE,  true); return;
3961   case vmIntrinsics::_compareAndSetLong:
3962   case vmIntrinsics::_compareAndSetInt:
3963   case vmIntrinsics::_compareAndSetReference : append_unsafe_CAS(callee); return;
3964   case vmIntrinsics::_getAndAddInt:
3965   case vmIntrinsics::_getAndAddLong          : append_unsafe_get_and_set(callee, true); return;
3966   case vmIntrinsics::_getAndSetInt           :
3967   case vmIntrinsics::_getAndSetLong          :
3968   case vmIntrinsics::_getAndSetReference     : append_unsafe_get_and_set(callee, false); return;
3969   case vmIntrinsics::_getCharStringU         : append_char_access(callee, false); return;
3970   case vmIntrinsics::_putCharStringU         : append_char_access(callee, true); return;
3971   case vmIntrinsics::_clone                  : append_alloc_array_copy(callee); return;
3972   default:
3973     break;
3974   }
3975   if (_inline_bailout_msg != nullptr) {
3976     return;
3977   }
3978 
3979   // create intrinsic node
3980   const bool has_receiver = !callee->is_static();
3981   ValueType* result_type = as_ValueType(callee->return_type());
3982   ValueStack* state_before = copy_state_for_exception();
3983 
3984   Values* args = state()->pop_arguments(callee->arg_size());
3985 
3986   if (is_profiling()) {
3987     // Don't profile in the special case where the root method
3988     // is the intrinsic
3989     if (callee != method()) {
3990       // Note that we'd collect profile data in this method if we wanted it.
3991       compilation()->set_would_profile(true);
3992       if (profile_calls()) {
3993         Value recv = nullptr;
3994         if (has_receiver) {
3995           recv = args->at(0);
3996           null_check(recv);
3997         }
3998         profile_call(callee, recv, nullptr, collect_args_for_profiling(args, callee, true), true);
3999       }
4000     }
4001   }
4002 
4003   Intrinsic* result = new Intrinsic(result_type, callee->intrinsic_id(),
4004                                     args, has_receiver, state_before,
4005                                     vmIntrinsics::preserves_state(id),
4006                                     vmIntrinsics::can_trap(id));
4007   // append instruction & push result
4008   Value value = append_split(result);
4009   if (result_type != voidType && !ignore_return) {
4010     push(result_type, value);
4011   }
4012 
4013   if (callee != method() && profile_return() && result_type->is_object_kind()) {
4014     profile_return_type(result, callee);
4015   }
4016 }
4017 
4018 bool GraphBuilder::try_inline_intrinsics(ciMethod* callee, bool ignore_return) {
4019   // For calling is_intrinsic_available we need to transition to
4020   // the '_thread_in_vm' state because is_intrinsic_available()
4021   // accesses critical VM-internal data.
4022   bool is_available = false;
4023   {
4024     VM_ENTRY_MARK;
4025     methodHandle mh(THREAD, callee->get_Method());
4026     is_available = _compilation->compiler()->is_intrinsic_available(mh, _compilation->directive());
4027   }
4028 
4029   if (!is_available) {
4030     if (!InlineNatives) {
4031       // Return false and also set message that the inlining of
4032       // intrinsics has been disabled in general.
4033       INLINE_BAILOUT("intrinsic method inlining disabled");
4034     } else {
4035       return false;
4036     }
4037   }
4038   build_graph_for_intrinsic(callee, ignore_return);
4039   if (_inline_bailout_msg != nullptr) {
4040     return false;
4041   }
4042   return true;
4043 }
4044 
4045 
4046 bool GraphBuilder::try_inline_jsr(int jsr_dest_bci) {
4047   // Introduce a new callee continuation point - all Ret instructions
4048   // will be replaced with Gotos to this point.
4049   if (next_bci() >= method()->code_size()) {
4050     return false;
4051   }
4052   BlockBegin* cont = block_at(next_bci());
4053   assert(cont != nullptr, "continuation must exist (BlockListBuilder starts a new block after a jsr");
4054 
4055   // Note: can not assign state to continuation yet, as we have to
4056   // pick up the state from the Ret instructions.
4057 
4058   // Push callee scope
4059   push_scope_for_jsr(cont, jsr_dest_bci);
4060 
4061   // Temporarily set up bytecode stream so we can append instructions
4062   // (only using the bci of this stream)
4063   scope_data()->set_stream(scope_data()->parent()->stream());
4064 
4065   BlockBegin* jsr_start_block = block_at(jsr_dest_bci);
4066   assert(jsr_start_block != nullptr, "jsr start block must exist");
4067   assert(!jsr_start_block->is_set(BlockBegin::was_visited_flag), "should not have visited jsr yet");
4068   Goto* goto_sub = new Goto(jsr_start_block, false);
4069   // Must copy state to avoid wrong sharing when parsing bytecodes
4070   assert(jsr_start_block->state() == nullptr, "should have fresh jsr starting block");
4071   jsr_start_block->set_state(copy_state_before_with_bci(jsr_dest_bci));
4072   append(goto_sub);
4073   _block->set_end(goto_sub);
4074   _last = _block = jsr_start_block;
4075 
4076   // Clear out bytecode stream
4077   scope_data()->set_stream(nullptr);
4078 
4079   scope_data()->add_to_work_list(jsr_start_block);
4080 
4081   // Ready to resume parsing in subroutine
4082   iterate_all_blocks();
4083 
4084   // If we bailed out during parsing, return immediately (this is bad news)
4085   CHECK_BAILOUT_(false);
4086 
4087   // Detect whether the continuation can actually be reached. If not,
4088   // it has not had state set by the join() operations in
4089   // iterate_bytecodes_for_block()/ret() and we should not touch the
4090   // iteration state. The calling activation of
4091   // iterate_bytecodes_for_block will then complete normally.
4092   if (cont->state() != nullptr) {
4093     if (!cont->is_set(BlockBegin::was_visited_flag)) {
4094       // add continuation to work list instead of parsing it immediately
4095       scope_data()->parent()->add_to_work_list(cont);
4096     }
4097   }
4098 
4099   assert(jsr_continuation() == cont, "continuation must not have changed");
4100   assert(!jsr_continuation()->is_set(BlockBegin::was_visited_flag) ||
4101          jsr_continuation()->is_set(BlockBegin::parser_loop_header_flag),
4102          "continuation can only be visited in case of backward branches");
4103   assert(_last && _last->as_BlockEnd(), "block must have end");
4104 
4105   // continuation is in work list, so end iteration of current block
4106   _skip_block = true;
4107   pop_scope_for_jsr();
4108 
4109   return true;
4110 }
4111 
4112 
4113 // Inline the entry of a synchronized method as a monitor enter and
4114 // register the exception handler which releases the monitor if an
4115 // exception is thrown within the callee. Note that the monitor enter
4116 // cannot throw an exception itself, because the receiver is
4117 // guaranteed to be non-null by the explicit null check at the
4118 // beginning of inlining.
4119 void GraphBuilder::inline_sync_entry(Value lock, BlockBegin* sync_handler) {
4120   assert(lock != nullptr && sync_handler != nullptr, "lock or handler missing");
4121 
4122   monitorenter(lock, SynchronizationEntryBCI);
4123   assert(_last->as_MonitorEnter() != nullptr, "monitor enter expected");
4124   _last->set_needs_null_check(false);
4125 
4126   sync_handler->set(BlockBegin::exception_entry_flag);
4127   sync_handler->set(BlockBegin::is_on_work_list_flag);
4128 
4129   ciExceptionHandler* desc = new ciExceptionHandler(method()->holder(), 0, method()->code_size(), -1, 0);
4130   XHandler* h = new XHandler(desc);
4131   h->set_entry_block(sync_handler);
4132   scope_data()->xhandlers()->append(h);
4133   scope_data()->set_has_handler();
4134 }
4135 
4136 
4137 // If an exception is thrown and not handled within an inlined
4138 // synchronized method, the monitor must be released before the
4139 // exception is rethrown in the outer scope. Generate the appropriate
4140 // instructions here.
4141 void GraphBuilder::fill_sync_handler(Value lock, BlockBegin* sync_handler, bool default_handler) {
4142   BlockBegin* orig_block = _block;
4143   ValueStack* orig_state = _state;
4144   Instruction* orig_last = _last;
4145   _last = _block = sync_handler;
4146   _state = sync_handler->state()->copy();
4147 
4148   assert(sync_handler != nullptr, "handler missing");
4149   assert(!sync_handler->is_set(BlockBegin::was_visited_flag), "is visited here");
4150 
4151   assert(lock != nullptr || default_handler, "lock or handler missing");
4152 
4153   XHandler* h = scope_data()->xhandlers()->remove_last();
4154   assert(h->entry_block() == sync_handler, "corrupt list of handlers");
4155 
4156   block()->set(BlockBegin::was_visited_flag);
4157   Value exception = append_with_bci(new ExceptionObject(), SynchronizationEntryBCI);
4158   assert(exception->is_pinned(), "must be");
4159 
4160   int bci = SynchronizationEntryBCI;
4161   if (compilation()->env()->dtrace_method_probes()) {
4162     // Report exit from inline methods.  We don't have a stream here
4163     // so pass an explicit bci of SynchronizationEntryBCI.
4164     Values* args = new Values(1);
4165     args->push(append_with_bci(new Constant(new MethodConstant(method())), bci));
4166     append_with_bci(new RuntimeCall(voidType, "dtrace_method_exit", CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_exit), args), bci);
4167   }
4168 
4169   if (lock) {
4170     assert(state()->locks_size() > 0 && state()->lock_at(state()->locks_size() - 1) == lock, "lock is missing");
4171     if (!lock->is_linked()) {
4172       lock = append_with_bci(lock, bci);
4173     }
4174 
4175     // exit the monitor in the context of the synchronized method
4176     monitorexit(lock, bci);
4177 
4178     // exit the context of the synchronized method
4179     if (!default_handler) {
4180       pop_scope();
4181       bci = _state->caller_state()->bci();
4182       _state = _state->caller_state()->copy_for_parsing();
4183     }
4184   }
4185 
4186   // perform the throw as if at the call site
4187   apush(exception);
4188   throw_op(bci);
4189 
4190   BlockEnd* end = last()->as_BlockEnd();
4191   block()->set_end(end);
4192 
4193   _block = orig_block;
4194   _state = orig_state;
4195   _last = orig_last;
4196 }
4197 
4198 
4199 bool GraphBuilder::try_inline_full(ciMethod* callee, bool holder_known, bool ignore_return, Bytecodes::Code bc, Value receiver) {
4200   assert(!callee->is_native(), "callee must not be native");
4201   if (CompilationPolicy::should_not_inline(compilation()->env(), callee)) {
4202     INLINE_BAILOUT("inlining prohibited by policy");
4203   }
4204   // first perform tests of things it's not possible to inline
4205   if (callee->has_exception_handlers() &&
4206       !InlineMethodsWithExceptionHandlers) INLINE_BAILOUT("callee has exception handlers");
4207   if (callee->is_synchronized() &&
4208       !InlineSynchronizedMethods         ) INLINE_BAILOUT("callee is synchronized");
4209   if (!callee->holder()->is_linked())      INLINE_BAILOUT("callee's klass not linked yet");
4210   if (bc == Bytecodes::_invokestatic &&
4211       !callee->holder()->is_initialized()) INLINE_BAILOUT("callee's klass not initialized yet");
4212   if (!callee->has_balanced_monitors())    INLINE_BAILOUT("callee's monitors do not match");
4213 
4214   // Proper inlining of methods with jsrs requires a little more work.
4215   if (callee->has_jsrs()                 ) INLINE_BAILOUT("jsrs not handled properly by inliner yet");
4216 
4217   if (is_profiling() && !callee->ensure_method_data()) {
4218     INLINE_BAILOUT("mdo allocation failed");
4219   }
4220 
4221   const bool is_invokedynamic = (bc == Bytecodes::_invokedynamic);
4222   const bool has_receiver = (bc != Bytecodes::_invokestatic && !is_invokedynamic);
4223 
4224   const int args_base = state()->stack_size() - callee->arg_size();
4225   assert(args_base >= 0, "stack underflow during inlining");
4226 
4227   Value recv = nullptr;
4228   if (has_receiver) {
4229     assert(!callee->is_static(), "callee must not be static");
4230     assert(callee->arg_size() > 0, "must have at least a receiver");
4231 
4232     recv = state()->stack_at(args_base);
4233     if (recv->is_null_obj()) {
4234       INLINE_BAILOUT("receiver is always null");
4235     }
4236   }
4237 
4238   // now perform tests that are based on flag settings
4239   bool inlinee_by_directive = compilation()->directive()->should_inline(callee);
4240   if (callee->force_inline() || inlinee_by_directive) {
4241     if (inline_level() > MaxForceInlineLevel                      ) INLINE_BAILOUT("MaxForceInlineLevel");
4242     if (recursive_inline_level(callee) > C1MaxRecursiveInlineLevel) INLINE_BAILOUT("recursive inlining too deep");
4243 
4244     const char* msg = "";
4245     if (callee->force_inline())  msg = "force inline by annotation";
4246     if (inlinee_by_directive)    msg = "force inline by CompileCommand";
4247     print_inlining(callee, msg);
4248   } else {
4249     // use heuristic controls on inlining
4250     if (inline_level() > C1MaxInlineLevel                       ) INLINE_BAILOUT("inlining too deep");
4251     int callee_recursive_level = recursive_inline_level(callee);
4252     if (callee_recursive_level > C1MaxRecursiveInlineLevel      ) INLINE_BAILOUT("recursive inlining too deep");
4253     if (callee->code_size_for_inlining() > max_inline_size()    ) INLINE_BAILOUT("callee is too large");
4254     // Additional condition to limit stack usage for non-recursive calls.
4255     if ((callee_recursive_level == 0) &&
4256         (callee->max_stack() + callee->max_locals() - callee->size_of_parameters() > C1InlineStackLimit)) {
4257       INLINE_BAILOUT("callee uses too much stack");
4258     }
4259 
4260     // don't inline throwable methods unless the inlining tree is rooted in a throwable class
4261     if (callee->name() == ciSymbols::object_initializer_name() &&
4262         callee->holder()->is_subclass_of(ciEnv::current()->Throwable_klass())) {
4263       // Throwable constructor call
4264       IRScope* top = scope();
4265       while (top->caller() != nullptr) {
4266         top = top->caller();
4267       }
4268       if (!top->method()->holder()->is_subclass_of(ciEnv::current()->Throwable_klass())) {
4269         INLINE_BAILOUT("don't inline Throwable constructors");
4270       }
4271     }
4272 
4273     if (compilation()->env()->num_inlined_bytecodes() > DesiredMethodLimit) {
4274       INLINE_BAILOUT("total inlining greater than DesiredMethodLimit");
4275     }
4276     // printing
4277     print_inlining(callee, "inline", /*success*/ true);
4278   }
4279 
4280   assert(bc != Bytecodes::_invokestatic || callee->holder()->is_initialized(), "required");
4281 
4282   // NOTE: Bailouts from this point on, which occur at the
4283   // GraphBuilder level, do not cause bailout just of the inlining but
4284   // in fact of the entire compilation.
4285 
4286   BlockBegin* orig_block = block();
4287 
4288   // Insert null check if necessary
4289   if (has_receiver) {
4290     // note: null check must happen even if first instruction of callee does
4291     //       an implicit null check since the callee is in a different scope
4292     //       and we must make sure exception handling does the right thing
4293     null_check(recv);
4294   }
4295 
4296   if (is_profiling()) {
4297     // Note that we'd collect profile data in this method if we wanted it.
4298     // this may be redundant here...
4299     compilation()->set_would_profile(true);
4300 
4301     if (profile_calls()) {
4302       int start = 0;
4303       Values* obj_args = args_list_for_profiling(callee, start, has_receiver);
4304       if (obj_args != nullptr) {
4305         int s = obj_args->capacity();
4306         // if called through method handle invoke, some arguments may have been popped
4307         for (int i = args_base+start, j = 0; j < obj_args->capacity() && i < state()->stack_size(); ) {
4308           Value v = state()->stack_at_inc(i);
4309           if (v->type()->is_object_kind()) {
4310             obj_args->push(v);
4311             j++;
4312           }
4313         }
4314         check_args_for_profiling(obj_args, s);
4315       }
4316       profile_call(callee, recv, holder_known ? callee->holder() : nullptr, obj_args, true);
4317     }
4318   }
4319 
4320   // Introduce a new callee continuation point - if the callee has
4321   // more than one return instruction or the return does not allow
4322   // fall-through of control flow, all return instructions of the
4323   // callee will need to be replaced by Goto's pointing to this
4324   // continuation point.
4325   BlockBegin* cont = block_at(next_bci());
4326   bool continuation_existed = true;
4327   if (cont == nullptr) {
4328     cont = new BlockBegin(next_bci());
4329     // low number so that continuation gets parsed as early as possible
4330     cont->set_depth_first_number(0);
4331     if (PrintInitialBlockList) {
4332       tty->print_cr("CFG: created block %d (bci %d) as continuation for inline at bci %d",
4333                     cont->block_id(), cont->bci(), bci());
4334     }
4335     continuation_existed = false;
4336   }
4337   // Record number of predecessors of continuation block before
4338   // inlining, to detect if inlined method has edges to its
4339   // continuation after inlining.
4340   int continuation_preds = cont->number_of_preds();
4341 
4342   // Push callee scope
4343   push_scope(callee, cont);
4344 
4345   // the BlockListBuilder for the callee could have bailed out
4346   if (bailed_out())
4347       return false;
4348 
4349   // Temporarily set up bytecode stream so we can append instructions
4350   // (only using the bci of this stream)
4351   scope_data()->set_stream(scope_data()->parent()->stream());
4352 
4353   // Pass parameters into callee state: add assignments
4354   // note: this will also ensure that all arguments are computed before being passed
4355   ValueStack* callee_state = state();
4356   ValueStack* caller_state = state()->caller_state();
4357   for (int i = args_base; i < caller_state->stack_size(); ) {
4358     const int arg_no = i - args_base;
4359     Value arg = caller_state->stack_at_inc(i);
4360     store_local(callee_state, arg, arg_no);
4361   }
4362 
4363   // Remove args from stack.
4364   // Note that we preserve locals state in case we can use it later
4365   // (see use of pop_scope() below)
4366   caller_state->truncate_stack(args_base);
4367   assert(callee_state->stack_size() == 0, "callee stack must be empty");
4368 
4369   Value lock = nullptr;
4370   BlockBegin* sync_handler = nullptr;
4371 
4372   // Inline the locking of the receiver if the callee is synchronized
4373   if (callee->is_synchronized()) {
4374     lock = callee->is_static() ? append(new Constant(new InstanceConstant(callee->holder()->java_mirror())))
4375                                : state()->local_at(0);
4376     sync_handler = new BlockBegin(SynchronizationEntryBCI);
4377     inline_sync_entry(lock, sync_handler);
4378   }
4379 
4380   if (compilation()->env()->dtrace_method_probes()) {
4381     Values* args = new Values(1);
4382     args->push(append(new Constant(new MethodConstant(method()))));
4383     append(new RuntimeCall(voidType, "dtrace_method_entry", CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_entry), args));
4384   }
4385 
4386   if (profile_inlined_calls()) {
4387     profile_invocation(callee, copy_state_before_with_bci(SynchronizationEntryBCI));
4388   }
4389 
4390   BlockBegin* callee_start_block = block_at(0);
4391   if (callee_start_block != nullptr) {
4392     assert(callee_start_block->is_set(BlockBegin::parser_loop_header_flag), "must be loop header");
4393     Goto* goto_callee = new Goto(callee_start_block, false);
4394     // The state for this goto is in the scope of the callee, so use
4395     // the entry bci for the callee instead of the call site bci.
4396     append_with_bci(goto_callee, 0);
4397     _block->set_end(goto_callee);
4398     callee_start_block->merge(callee_state, compilation()->has_irreducible_loops());
4399 
4400     _last = _block = callee_start_block;
4401 
4402     scope_data()->add_to_work_list(callee_start_block);
4403   }
4404 
4405   // Clear out bytecode stream
4406   scope_data()->set_stream(nullptr);
4407   scope_data()->set_ignore_return(ignore_return);
4408 
4409   CompileLog* log = compilation()->log();
4410   if (log != nullptr) log->head("parse method='%d'", log->identify(callee));
4411 
4412   // Ready to resume parsing in callee (either in the same block we
4413   // were in before or in the callee's start block)
4414   iterate_all_blocks(callee_start_block == nullptr);
4415 
4416   if (log != nullptr) log->done("parse");
4417 
4418   // If we bailed out during parsing, return immediately (this is bad news)
4419   if (bailed_out())
4420       return false;
4421 
4422   // iterate_all_blocks theoretically traverses in random order; in
4423   // practice, we have only traversed the continuation if we are
4424   // inlining into a subroutine
4425   assert(continuation_existed ||
4426          !continuation()->is_set(BlockBegin::was_visited_flag),
4427          "continuation should not have been parsed yet if we created it");
4428 
4429   // At this point we are almost ready to return and resume parsing of
4430   // the caller back in the GraphBuilder. The only thing we want to do
4431   // first is an optimization: during parsing of the callee we
4432   // generated at least one Goto to the continuation block. If we
4433   // generated exactly one, and if the inlined method spanned exactly
4434   // one block (and we didn't have to Goto its entry), then we snip
4435   // off the Goto to the continuation, allowing control to fall
4436   // through back into the caller block and effectively performing
4437   // block merging. This allows load elimination and CSE to take place
4438   // across multiple callee scopes if they are relatively simple, and
4439   // is currently essential to making inlining profitable.
4440   if (num_returns() == 1
4441       && block() == orig_block
4442       && block() == inline_cleanup_block()) {
4443     _last  = inline_cleanup_return_prev();
4444     _state = inline_cleanup_state();
4445   } else if (continuation_preds == cont->number_of_preds()) {
4446     // Inlining caused that the instructions after the invoke in the
4447     // caller are not reachable any more. So skip filling this block
4448     // with instructions!
4449     assert(cont == continuation(), "");
4450     assert(_last && _last->as_BlockEnd(), "");
4451     _skip_block = true;
4452   } else {
4453     // Resume parsing in continuation block unless it was already parsed.
4454     // Note that if we don't change _last here, iteration in
4455     // iterate_bytecodes_for_block will stop when we return.
4456     if (!continuation()->is_set(BlockBegin::was_visited_flag)) {
4457       // add continuation to work list instead of parsing it immediately
4458       assert(_last && _last->as_BlockEnd(), "");
4459       scope_data()->parent()->add_to_work_list(continuation());
4460       _skip_block = true;
4461     }
4462   }
4463 
4464   // Fill the exception handler for synchronized methods with instructions
4465   if (callee->is_synchronized() && sync_handler->state() != nullptr) {
4466     fill_sync_handler(lock, sync_handler);
4467   } else {
4468     pop_scope();
4469   }
4470 
4471   compilation()->notice_inlined_method(callee);
4472 
4473   return true;
4474 }
4475 
4476 
4477 bool GraphBuilder::try_method_handle_inline(ciMethod* callee, bool ignore_return) {
4478   ValueStack* state_before = copy_state_before();
4479   vmIntrinsics::ID iid = callee->intrinsic_id();
4480   switch (iid) {
4481   case vmIntrinsics::_invokeBasic:
4482     {
4483       // get MethodHandle receiver
4484       const int args_base = state()->stack_size() - callee->arg_size();
4485       ValueType* type = state()->stack_at(args_base)->type();
4486       if (type->is_constant()) {
4487         ciObject* mh = type->as_ObjectType()->constant_value();
4488         if (mh->is_method_handle()) {
4489           ciMethod* target = mh->as_method_handle()->get_vmtarget();
4490 
4491           // We don't do CHA here so only inline static and statically bindable methods.
4492           if (target->is_static() || target->can_be_statically_bound()) {
4493             if (ciMethod::is_consistent_info(callee, target)) {
4494               Bytecodes::Code bc = target->is_static() ? Bytecodes::_invokestatic : Bytecodes::_invokevirtual;
4495               ignore_return = ignore_return || (callee->return_type()->is_void() && !target->return_type()->is_void());
4496               if (try_inline(target, /*holder_known*/ !callee->is_static(), ignore_return, bc)) {
4497                 return true;
4498               }
4499             } else {
4500               print_inlining(target, "signatures mismatch", /*success*/ false);
4501             }
4502           } else {
4503             assert(false, "no inlining through MH::invokeBasic"); // missing optimization opportunity due to suboptimal LF shape
4504             print_inlining(target, "not static or statically bindable", /*success*/ false);
4505           }
4506         } else {
4507           assert(mh->is_null_object(), "not a null");
4508           print_inlining(callee, "receiver is always null", /*success*/ false);
4509         }
4510       } else {
4511         print_inlining(callee, "receiver not constant", /*success*/ false);
4512       }
4513     }
4514     break;
4515 
4516   case vmIntrinsics::_linkToVirtual:
4517   case vmIntrinsics::_linkToStatic:
4518   case vmIntrinsics::_linkToSpecial:
4519   case vmIntrinsics::_linkToInterface:
4520     {
4521       // pop MemberName argument
4522       const int args_base = state()->stack_size() - callee->arg_size();
4523       ValueType* type = apop()->type();
4524       if (type->is_constant()) {
4525         ciMethod* target = type->as_ObjectType()->constant_value()->as_member_name()->get_vmtarget();
4526         ignore_return = ignore_return || (callee->return_type()->is_void() && !target->return_type()->is_void());
4527         // If the target is another method handle invoke, try to recursively get
4528         // a better target.
4529         if (target->is_method_handle_intrinsic()) {
4530           if (try_method_handle_inline(target, ignore_return)) {
4531             return true;
4532           }
4533         } else if (!ciMethod::is_consistent_info(callee, target)) {
4534           print_inlining(target, "signatures mismatch", /*success*/ false);
4535         } else {
4536           ciSignature* signature = target->signature();
4537           const int receiver_skip = target->is_static() ? 0 : 1;
4538           // Cast receiver to its type.
4539           if (!target->is_static()) {
4540             ciKlass* tk = signature->accessing_klass();
4541             Value obj = state()->stack_at(args_base);
4542             if (obj->exact_type() == nullptr &&
4543                 obj->declared_type() != tk && tk != compilation()->env()->Object_klass()) {
4544               TypeCast* c = new TypeCast(tk, obj, state_before);
4545               append(c);
4546               state()->stack_at_put(args_base, c);
4547             }
4548           }
4549           // Cast reference arguments to its type.
4550           for (int i = 0, j = 0; i < signature->count(); i++) {
4551             ciType* t = signature->type_at(i);
4552             if (t->is_klass()) {
4553               ciKlass* tk = t->as_klass();
4554               Value obj = state()->stack_at(args_base + receiver_skip + j);
4555               if (obj->exact_type() == nullptr &&
4556                   obj->declared_type() != tk && tk != compilation()->env()->Object_klass()) {
4557                 TypeCast* c = new TypeCast(t, obj, state_before);
4558                 append(c);
4559                 state()->stack_at_put(args_base + receiver_skip + j, c);
4560               }
4561             }
4562             j += t->size();  // long and double take two slots
4563           }
4564           // We don't do CHA here so only inline static and statically bindable methods.
4565           if (target->is_static() || target->can_be_statically_bound()) {
4566             Bytecodes::Code bc = target->is_static() ? Bytecodes::_invokestatic : Bytecodes::_invokevirtual;
4567             if (try_inline(target, /*holder_known*/ !callee->is_static(), ignore_return, bc)) {
4568               return true;
4569             }
4570           } else {
4571             print_inlining(target, "not static or statically bindable", /*success*/ false);
4572           }
4573         }
4574       } else {
4575         print_inlining(callee, "MemberName not constant", /*success*/ false);
4576       }
4577     }
4578     break;
4579 
4580   case vmIntrinsics::_linkToNative:
4581     print_inlining(callee, "native call", /*success*/ false);
4582     break;
4583 
4584   default:
4585     fatal("unexpected intrinsic %d: %s", vmIntrinsics::as_int(iid), vmIntrinsics::name_at(iid));
4586     break;
4587   }
4588   set_state(state_before->copy_for_parsing());
4589   return false;
4590 }
4591 
4592 
4593 void GraphBuilder::inline_bailout(const char* msg) {
4594   assert(msg != nullptr, "inline bailout msg must exist");
4595   _inline_bailout_msg = msg;
4596 }
4597 
4598 
4599 void GraphBuilder::clear_inline_bailout() {
4600   _inline_bailout_msg = nullptr;
4601 }
4602 
4603 
4604 void GraphBuilder::push_root_scope(IRScope* scope, BlockList* bci2block, BlockBegin* start) {
4605   ScopeData* data = new ScopeData(nullptr);
4606   data->set_scope(scope);
4607   data->set_bci2block(bci2block);
4608   _scope_data = data;
4609   _block = start;
4610 }
4611 
4612 
4613 void GraphBuilder::push_scope(ciMethod* callee, BlockBegin* continuation) {
4614   IRScope* callee_scope = new IRScope(compilation(), scope(), bci(), callee, -1, false);
4615   scope()->add_callee(callee_scope);
4616 
4617   BlockListBuilder blb(compilation(), callee_scope, -1);
4618   CHECK_BAILOUT();
4619 
4620   if (!blb.bci2block()->at(0)->is_set(BlockBegin::parser_loop_header_flag)) {
4621     // this scope can be inlined directly into the caller so remove
4622     // the block at bci 0.
4623     blb.bci2block()->at_put(0, nullptr);
4624   }
4625 
4626   set_state(new ValueStack(callee_scope, state()->copy(ValueStack::CallerState, bci())));
4627 
4628   ScopeData* data = new ScopeData(scope_data());
4629   data->set_scope(callee_scope);
4630   data->set_bci2block(blb.bci2block());
4631   data->set_continuation(continuation);
4632   _scope_data = data;
4633 }
4634 
4635 
4636 void GraphBuilder::push_scope_for_jsr(BlockBegin* jsr_continuation, int jsr_dest_bci) {
4637   ScopeData* data = new ScopeData(scope_data());
4638   data->set_parsing_jsr();
4639   data->set_jsr_entry_bci(jsr_dest_bci);
4640   data->set_jsr_return_address_local(-1);
4641   // Must clone bci2block list as we will be mutating it in order to
4642   // properly clone all blocks in jsr region as well as exception
4643   // handlers containing rets
4644   BlockList* new_bci2block = new BlockList(bci2block()->length());
4645   new_bci2block->appendAll(bci2block());
4646   data->set_bci2block(new_bci2block);
4647   data->set_scope(scope());
4648   data->setup_jsr_xhandlers();
4649   data->set_continuation(continuation());
4650   data->set_jsr_continuation(jsr_continuation);
4651   _scope_data = data;
4652 }
4653 
4654 
4655 void GraphBuilder::pop_scope() {
4656   int number_of_locks = scope()->number_of_locks();
4657   _scope_data = scope_data()->parent();
4658   // accumulate minimum number of monitor slots to be reserved
4659   scope()->set_min_number_of_locks(number_of_locks);
4660 }
4661 
4662 
4663 void GraphBuilder::pop_scope_for_jsr() {
4664   _scope_data = scope_data()->parent();
4665 }
4666 
4667 void GraphBuilder::append_unsafe_get(ciMethod* callee, BasicType t, bool is_volatile) {
4668   Values* args = state()->pop_arguments(callee->arg_size());
4669   null_check(args->at(0));
4670   Instruction* offset = args->at(2);
4671 #ifndef _LP64
4672   offset = append(new Convert(Bytecodes::_l2i, offset, as_ValueType(T_INT)));
4673 #endif
4674   Instruction* op = append(new UnsafeGet(t, args->at(1), offset, is_volatile));
4675   push(op->type(), op);
4676   compilation()->set_has_unsafe_access(true);
4677 }
4678 
4679 
4680 void GraphBuilder::append_unsafe_put(ciMethod* callee, BasicType t, bool is_volatile) {
4681   Values* args = state()->pop_arguments(callee->arg_size());
4682   null_check(args->at(0));
4683   Instruction* offset = args->at(2);
4684 #ifndef _LP64
4685   offset = append(new Convert(Bytecodes::_l2i, offset, as_ValueType(T_INT)));
4686 #endif
4687   Value val = args->at(3);
4688   if (t == T_BOOLEAN) {
4689     Value mask = append(new Constant(new IntConstant(1)));
4690     val = append(new LogicOp(Bytecodes::_iand, val, mask));
4691   }
4692   Instruction* op = append(new UnsafePut(t, args->at(1), offset, val, is_volatile));
4693   compilation()->set_has_unsafe_access(true);
4694   kill_all();
4695 }
4696 
4697 void GraphBuilder::append_unsafe_CAS(ciMethod* callee) {
4698   ValueStack* state_before = copy_state_for_exception();
4699   ValueType* result_type = as_ValueType(callee->return_type());
4700   assert(result_type->is_int(), "int result");
4701   Values* args = state()->pop_arguments(callee->arg_size());
4702 
4703   // Pop off some args to specially handle, then push back
4704   Value newval = args->pop();
4705   Value cmpval = args->pop();
4706   Value offset = args->pop();
4707   Value src = args->pop();
4708   Value unsafe_obj = args->pop();
4709 
4710   // Separately handle the unsafe arg. It is not needed for code
4711   // generation, but must be null checked
4712   null_check(unsafe_obj);
4713 
4714 #ifndef _LP64
4715   offset = append(new Convert(Bytecodes::_l2i, offset, as_ValueType(T_INT)));
4716 #endif
4717 
4718   args->push(src);
4719   args->push(offset);
4720   args->push(cmpval);
4721   args->push(newval);
4722 
4723   // An unsafe CAS can alias with other field accesses, but we don't
4724   // know which ones so mark the state as no preserved.  This will
4725   // cause CSE to invalidate memory across it.
4726   bool preserves_state = false;
4727   Intrinsic* result = new Intrinsic(result_type, callee->intrinsic_id(), args, false, state_before, preserves_state);
4728   append_split(result);
4729   push(result_type, result);
4730   compilation()->set_has_unsafe_access(true);
4731 }
4732 
4733 void GraphBuilder::append_char_access(ciMethod* callee, bool is_store) {
4734   // This intrinsic accesses byte[] array as char[] array. Computing the offsets
4735   // correctly requires matched array shapes.
4736   assert (arrayOopDesc::base_offset_in_bytes(T_CHAR) == arrayOopDesc::base_offset_in_bytes(T_BYTE),
4737           "sanity: byte[] and char[] bases agree");
4738   assert (type2aelembytes(T_CHAR) == type2aelembytes(T_BYTE)*2,
4739           "sanity: byte[] and char[] scales agree");
4740 
4741   ValueStack* state_before = copy_state_indexed_access();
4742   compilation()->set_has_access_indexed(true);
4743   Values* args = state()->pop_arguments(callee->arg_size());
4744   Value array = args->at(0);
4745   Value index = args->at(1);
4746   if (is_store) {
4747     Value value = args->at(2);
4748     Instruction* store = append(new StoreIndexed(array, index, nullptr, T_CHAR, value, state_before, false, true));
4749     store->set_flag(Instruction::NeedsRangeCheckFlag, false);
4750     _memory->store_value(value);
4751   } else {
4752     Instruction* load = append(new LoadIndexed(array, index, nullptr, T_CHAR, state_before, true));
4753     load->set_flag(Instruction::NeedsRangeCheckFlag, false);
4754     push(load->type(), load);
4755   }
4756 }
4757 
4758 void GraphBuilder::append_alloc_array_copy(ciMethod* callee) {
4759   const int args_base = state()->stack_size() - callee->arg_size();
4760   ciType* receiver_type = state()->stack_at(args_base)->exact_type();
4761   if (receiver_type == nullptr) {
4762     inline_bailout("must have a receiver");
4763     return;
4764   }
4765   if (!receiver_type->is_type_array_klass()) {
4766     inline_bailout("clone array not primitive");
4767     return;
4768   }
4769 
4770   ValueStack* state_before = copy_state_before();
4771   state_before->set_force_reexecute();
4772   Value src = apop();
4773   BasicType basic_type = src->exact_type()->as_array_klass()->element_type()->basic_type();
4774   Value length = append(new ArrayLength(src, state_before));
4775   Value new_array = append_split(new NewTypeArray(length, basic_type, state_before, false));
4776 
4777   ValueType* result_type = as_ValueType(callee->return_type());
4778   vmIntrinsics::ID id = vmIntrinsics::_arraycopy;
4779   Values* args = new Values(5);
4780   args->push(src);
4781   args->push(append(new Constant(new IntConstant(0))));
4782   args->push(new_array);
4783   args->push(append(new Constant(new IntConstant(0))));
4784   args->push(length);
4785   const bool has_receiver = true;
4786   Intrinsic* array_copy = new Intrinsic(result_type, id,
4787                                     args, has_receiver, state_before,
4788                                     vmIntrinsics::preserves_state(id),
4789                                     vmIntrinsics::can_trap(id));
4790   array_copy->set_flag(Instruction::OmitChecksFlag, true);
4791   append_split(array_copy);
4792   apush(new_array);
4793   append(new MemBar(lir_membar_storestore));
4794 }
4795 
4796 void GraphBuilder::print_inlining(ciMethod* callee, const char* msg, bool success) {
4797   CompileLog* log = compilation()->log();
4798   if (log != nullptr) {
4799     assert(msg != nullptr, "inlining msg should not be null!");
4800     if (success) {
4801       log->inline_success(msg);
4802     } else {
4803       log->inline_fail(msg);
4804     }
4805   }
4806   EventCompilerInlining event;
4807   if (event.should_commit()) {
4808     CompilerEvent::InlineEvent::post(event, compilation()->env()->task()->compile_id(), method()->get_Method(), callee, success, msg, bci());
4809   }
4810 
4811   CompileTask::print_inlining_ul(callee, scope()->level(), bci(), inlining_result_of(success), msg);
4812 
4813   if (!compilation()->directive()->PrintInliningOption) {
4814     return;
4815   }
4816   CompileTask::print_inlining_tty(callee, scope()->level(), bci(), inlining_result_of(success), msg);
4817   if (success && CIPrintMethodCodes) {
4818     callee->print_codes();
4819   }
4820 }
4821 
4822 void GraphBuilder::append_unsafe_get_and_set(ciMethod* callee, bool is_add) {
4823   Values* args = state()->pop_arguments(callee->arg_size());
4824   BasicType t = callee->return_type()->basic_type();
4825   null_check(args->at(0));
4826   Instruction* offset = args->at(2);
4827 #ifndef _LP64
4828   offset = append(new Convert(Bytecodes::_l2i, offset, as_ValueType(T_INT)));
4829 #endif
4830   Instruction* op = append(new UnsafeGetAndSet(t, args->at(1), offset, args->at(3), is_add));
4831   compilation()->set_has_unsafe_access(true);
4832   kill_all();
4833   push(op->type(), op);
4834 }
4835 
4836 #ifndef PRODUCT
4837 void GraphBuilder::print_stats() {
4838   if (UseLocalValueNumbering) {
4839     vmap()->print();
4840   }
4841 }
4842 #endif // PRODUCT
4843 
4844 void GraphBuilder::profile_call(ciMethod* callee, Value recv, ciKlass* known_holder, Values* obj_args, bool inlined) {
4845   assert(known_holder == nullptr || (known_holder->is_instance_klass() &&
4846                                   (!known_holder->is_interface() ||
4847                                    ((ciInstanceKlass*)known_holder)->has_nonstatic_concrete_methods())), "should be non-static concrete method");
4848   if (known_holder != nullptr) {
4849     if (known_holder->exact_klass() == nullptr) {
4850       known_holder = compilation()->cha_exact_type(known_holder);
4851     }
4852   }
4853 
4854   append(new ProfileCall(method(), bci(), callee, recv, known_holder, obj_args, inlined));
4855 }
4856 
4857 void GraphBuilder::profile_return_type(Value ret, ciMethod* callee, ciMethod* m, int invoke_bci) {
4858   assert((m == nullptr) == (invoke_bci < 0), "invalid method and invalid bci together");
4859   if (m == nullptr) {
4860     m = method();
4861   }
4862   if (invoke_bci < 0) {
4863     invoke_bci = bci();
4864   }
4865   ciMethodData* md = m->method_data_or_null();
4866   ciProfileData* data = md->bci_to_data(invoke_bci);
4867   if (data != nullptr && (data->is_CallTypeData() || data->is_VirtualCallTypeData())) {
4868     bool has_return = data->is_CallTypeData() ? ((ciCallTypeData*)data)->has_return() : ((ciVirtualCallTypeData*)data)->has_return();
4869     if (has_return) {
4870       append(new ProfileReturnType(m , invoke_bci, callee, ret));
4871     }
4872   }
4873 }
4874 
4875 void GraphBuilder::profile_invocation(ciMethod* callee, ValueStack* state) {
4876   append(new ProfileInvoke(callee, state));
4877 }