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