1 /*
   2  * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "compiler/compileLog.hpp"
  27 #include "interpreter/linkResolver.hpp"
  28 #include "memory/resourceArea.hpp"
  29 #include "oops/method.hpp"
  30 #include "opto/addnode.hpp"
  31 #include "opto/c2compiler.hpp"
  32 #include "opto/castnode.hpp"
  33 #include "opto/idealGraphPrinter.hpp"
  34 #include "opto/locknode.hpp"
  35 #include "opto/memnode.hpp"
  36 #include "opto/opaquenode.hpp"
  37 #include "opto/parse.hpp"
  38 #include "opto/rootnode.hpp"
  39 #include "opto/runtime.hpp"
  40 #include "runtime/arguments.hpp"
  41 #include "runtime/handles.inline.hpp"
  42 #include "runtime/sharedRuntime.hpp"
  43 #include "utilities/copy.hpp"
  44 
  45 // Static array so we can figure out which bytecodes stop us from compiling
  46 // the most. Some of the non-static variables are needed in bytecodeInfo.cpp
  47 // and eventually should be encapsulated in a proper class (gri 8/18/98).
  48 
  49 #ifndef PRODUCT
  50 int nodes_created              = 0;
  51 int methods_parsed             = 0;
  52 int methods_seen               = 0;
  53 int blocks_parsed              = 0;
  54 int blocks_seen                = 0;
  55 
  56 int explicit_null_checks_inserted = 0;
  57 int explicit_null_checks_elided   = 0;
  58 int all_null_checks_found         = 0;
  59 int implicit_null_checks          = 0;
  60 
  61 bool Parse::BytecodeParseHistogram::_initialized = false;
  62 uint Parse::BytecodeParseHistogram::_bytecodes_parsed [Bytecodes::number_of_codes];
  63 uint Parse::BytecodeParseHistogram::_nodes_constructed[Bytecodes::number_of_codes];
  64 uint Parse::BytecodeParseHistogram::_nodes_transformed[Bytecodes::number_of_codes];
  65 uint Parse::BytecodeParseHistogram::_new_values       [Bytecodes::number_of_codes];
  66 
  67 //------------------------------print_statistics-------------------------------
  68 void Parse::print_statistics() {
  69   tty->print_cr("--- Compiler Statistics ---");
  70   tty->print("Methods seen: %d  Methods parsed: %d", methods_seen, methods_parsed);
  71   tty->print("  Nodes created: %d", nodes_created);
  72   tty->cr();
  73   if (methods_seen != methods_parsed) {
  74     tty->print_cr("Reasons for parse failures (NOT cumulative):");
  75   }
  76   tty->print_cr("Blocks parsed: %d  Blocks seen: %d", blocks_parsed, blocks_seen);
  77 
  78   if (explicit_null_checks_inserted) {
  79     tty->print_cr("%d original NULL checks - %d elided (%2d%%); optimizer leaves %d,",
  80                   explicit_null_checks_inserted, explicit_null_checks_elided,
  81                   (100*explicit_null_checks_elided)/explicit_null_checks_inserted,
  82                   all_null_checks_found);
  83   }
  84   if (all_null_checks_found) {
  85     tty->print_cr("%d made implicit (%2d%%)", implicit_null_checks,
  86                   (100*implicit_null_checks)/all_null_checks_found);
  87   }
  88   if (SharedRuntime::_implicit_null_throws) {
  89     tty->print_cr("%d implicit null exceptions at runtime",
  90                   SharedRuntime::_implicit_null_throws);
  91   }
  92 
  93   if (PrintParseStatistics && BytecodeParseHistogram::initialized()) {
  94     BytecodeParseHistogram::print();
  95   }
  96 }
  97 #endif
  98 
  99 //------------------------------ON STACK REPLACEMENT---------------------------
 100 
 101 // Construct a node which can be used to get incoming state for
 102 // on stack replacement.
 103 Node *Parse::fetch_interpreter_state(int index,
 104                                      BasicType bt,
 105                                      Node *local_addrs,
 106                                      Node *local_addrs_base) {
 107   Node *mem = memory(Compile::AliasIdxRaw);
 108   Node *adr = basic_plus_adr( local_addrs_base, local_addrs, -index*wordSize );
 109   Node *ctl = control();
 110 
 111   // Very similar to LoadNode::make, except we handle un-aligned longs and
 112   // doubles on Sparc.  Intel can handle them just fine directly.
 113   Node *l = NULL;
 114   switch (bt) {                // Signature is flattened
 115   case T_INT:     l = new LoadINode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInt::INT,        MemNode::unordered); break;
 116   case T_FLOAT:   l = new LoadFNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::FLOAT,         MemNode::unordered); break;
 117   case T_ADDRESS: l = new LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM,  MemNode::unordered); break;
 118   case T_OBJECT:  l = new LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInstPtr::BOTTOM, MemNode::unordered); break;
 119   case T_LONG:
 120   case T_DOUBLE: {
 121     // Since arguments are in reverse order, the argument address 'adr'
 122     // refers to the back half of the long/double.  Recompute adr.
 123     adr = basic_plus_adr(local_addrs_base, local_addrs, -(index+1)*wordSize);
 124     if (Matcher::misaligned_doubles_ok) {
 125       l = (bt == T_DOUBLE)
 126         ? (Node*)new LoadDNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::DOUBLE, MemNode::unordered)
 127         : (Node*)new LoadLNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeLong::LONG, MemNode::unordered);
 128     } else {
 129       l = (bt == T_DOUBLE)
 130         ? (Node*)new LoadD_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered)
 131         : (Node*)new LoadL_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered);
 132     }
 133     break;
 134   }
 135   default: ShouldNotReachHere();
 136   }
 137   return _gvn.transform(l);
 138 }
 139 
 140 // Helper routine to prevent the interpreter from handing
 141 // unexpected typestate to an OSR method.
 142 // The Node l is a value newly dug out of the interpreter frame.
 143 // The type is the type predicted by ciTypeFlow.  Note that it is
 144 // not a general type, but can only come from Type::get_typeflow_type.
 145 // The safepoint is a map which will feed an uncommon trap.
 146 Node* Parse::check_interpreter_type(Node* l, const Type* type,
 147                                     SafePointNode* &bad_type_exit) {
 148 
 149   const TypeOopPtr* tp = type->isa_oopptr();
 150 
 151   // TypeFlow may assert null-ness if a type appears unloaded.
 152   if (type == TypePtr::NULL_PTR ||
 153       (tp != NULL && !tp->klass()->is_loaded())) {
 154     // Value must be null, not a real oop.
 155     Node* chk = _gvn.transform( new CmpPNode(l, null()) );
 156     Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
 157     IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
 158     set_control(_gvn.transform( new IfTrueNode(iff) ));
 159     Node* bad_type = _gvn.transform( new IfFalseNode(iff) );
 160     bad_type_exit->control()->add_req(bad_type);
 161     l = null();
 162   }
 163 
 164   // Typeflow can also cut off paths from the CFG, based on
 165   // types which appear unloaded, or call sites which appear unlinked.
 166   // When paths are cut off, values at later merge points can rise
 167   // toward more specific classes.  Make sure these specific classes
 168   // are still in effect.
 169   if (tp != NULL && tp->klass() != C->env()->Object_klass()) {
 170     // TypeFlow asserted a specific object type.  Value must have that type.
 171     Node* bad_type_ctrl = NULL;
 172     l = gen_checkcast(l, makecon(TypeKlassPtr::make(tp->klass())), &bad_type_ctrl);
 173     bad_type_exit->control()->add_req(bad_type_ctrl);
 174   }
 175 
 176   BasicType bt_l = _gvn.type(l)->basic_type();
 177   BasicType bt_t = type->basic_type();
 178   assert(_gvn.type(l)->higher_equal(type), "must constrain OSR typestate");
 179   return l;
 180 }
 181 
 182 // Helper routine which sets up elements of the initial parser map when
 183 // performing a parse for on stack replacement.  Add values into map.
 184 // The only parameter contains the address of a interpreter arguments.
 185 void Parse::load_interpreter_state(Node* osr_buf) {
 186   int index;
 187   int max_locals = jvms()->loc_size();
 188   int max_stack  = jvms()->stk_size();
 189 
 190 
 191   // Mismatch between method and jvms can occur since map briefly held
 192   // an OSR entry state (which takes up one RawPtr word).
 193   assert(max_locals == method()->max_locals(), "sanity");
 194   assert(max_stack  >= method()->max_stack(),  "sanity");
 195   assert((int)jvms()->endoff() == TypeFunc::Parms + max_locals + max_stack, "sanity");
 196   assert((int)jvms()->endoff() == (int)map()->req(), "sanity");
 197 
 198   // Find the start block.
 199   Block* osr_block = start_block();
 200   assert(osr_block->start() == osr_bci(), "sanity");
 201 
 202   // Set initial BCI.
 203   set_parse_bci(osr_block->start());
 204 
 205   // Set initial stack depth.
 206   set_sp(osr_block->start_sp());
 207 
 208   // Check bailouts.  We currently do not perform on stack replacement
 209   // of loops in catch blocks or loops which branch with a non-empty stack.
 210   if (sp() != 0) {
 211     C->record_method_not_compilable("OSR starts with non-empty stack");
 212     return;
 213   }
 214   // Do not OSR inside finally clauses:
 215   if (osr_block->has_trap_at(osr_block->start())) {
 216     C->record_method_not_compilable("OSR starts with an immediate trap");
 217     return;
 218   }
 219 
 220   // Commute monitors from interpreter frame to compiler frame.
 221   assert(jvms()->monitor_depth() == 0, "should be no active locks at beginning of osr");
 222   int mcnt = osr_block->flow()->monitor_count();
 223   Node *monitors_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals+mcnt*2-1)*wordSize);
 224   for (index = 0; index < mcnt; index++) {
 225     // Make a BoxLockNode for the monitor.
 226     Node *box = _gvn.transform(new BoxLockNode(next_monitor()));
 227 
 228 
 229     // Displaced headers and locked objects are interleaved in the
 230     // temp OSR buffer.  We only copy the locked objects out here.
 231     // Fetch the locked object from the OSR temp buffer and copy to our fastlock node.
 232     Node *lock_object = fetch_interpreter_state(index*2, T_OBJECT, monitors_addr, osr_buf);
 233     // Try and copy the displaced header to the BoxNode
 234     Node *displaced_hdr = fetch_interpreter_state((index*2) + 1, T_ADDRESS, monitors_addr, osr_buf);
 235 
 236 
 237     store_to_memory(control(), box, displaced_hdr, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
 238 
 239     // Build a bogus FastLockNode (no code will be generated) and push the
 240     // monitor into our debug info.
 241     const FastLockNode *flock = _gvn.transform(new FastLockNode( 0, lock_object, box ))->as_FastLock();
 242     map()->push_monitor(flock);
 243 
 244     // If the lock is our method synchronization lock, tuck it away in
 245     // _sync_lock for return and rethrow exit paths.
 246     if (index == 0 && method()->is_synchronized()) {
 247       _synch_lock = flock;
 248     }
 249   }
 250 
 251   // Use the raw liveness computation to make sure that unexpected
 252   // values don't propagate into the OSR frame.
 253   MethodLivenessResult live_locals = method()->liveness_at_bci(osr_bci());
 254   if (!live_locals.is_valid()) {
 255     // Degenerate or breakpointed method.
 256     C->record_method_not_compilable("OSR in empty or breakpointed method");
 257     return;
 258   }
 259 
 260   // Extract the needed locals from the interpreter frame.
 261   Node *locals_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals-1)*wordSize);
 262 
 263   // find all the locals that the interpreter thinks contain live oops
 264   const ResourceBitMap live_oops = method()->live_local_oops_at_bci(osr_bci());
 265   for (index = 0; index < max_locals; index++) {
 266 
 267     if (!live_locals.at(index)) {
 268       continue;
 269     }
 270 
 271     const Type *type = osr_block->local_type_at(index);
 272 
 273     if (type->isa_oopptr() != NULL) {
 274 
 275       // 6403625: Verify that the interpreter oopMap thinks that the oop is live
 276       // else we might load a stale oop if the MethodLiveness disagrees with the
 277       // result of the interpreter. If the interpreter says it is dead we agree
 278       // by making the value go to top.
 279       //
 280 
 281       if (!live_oops.at(index)) {
 282         if (C->log() != NULL) {
 283           C->log()->elem("OSR_mismatch local_index='%d'",index);
 284         }
 285         set_local(index, null());
 286         // and ignore it for the loads
 287         continue;
 288       }
 289     }
 290 
 291     // Filter out TOP, HALF, and BOTTOM.  (Cf. ensure_phi.)
 292     if (type == Type::TOP || type == Type::HALF) {
 293       continue;
 294     }
 295     // If the type falls to bottom, then this must be a local that
 296     // is mixing ints and oops or some such.  Forcing it to top
 297     // makes it go dead.
 298     if (type == Type::BOTTOM) {
 299       continue;
 300     }
 301     // Construct code to access the appropriate local.
 302     BasicType bt = type->basic_type();
 303     if (type == TypePtr::NULL_PTR) {
 304       // Ptr types are mixed together with T_ADDRESS but NULL is
 305       // really for T_OBJECT types so correct it.
 306       bt = T_OBJECT;
 307     }
 308     Node *value = fetch_interpreter_state(index, bt, locals_addr, osr_buf);
 309     set_local(index, value);
 310   }
 311 
 312   // Extract the needed stack entries from the interpreter frame.
 313   for (index = 0; index < sp(); index++) {
 314     const Type *type = osr_block->stack_type_at(index);
 315     if (type != Type::TOP) {
 316       // Currently the compiler bails out when attempting to on stack replace
 317       // at a bci with a non-empty stack.  We should not reach here.
 318       ShouldNotReachHere();
 319     }
 320   }
 321 
 322   // End the OSR migration
 323   make_runtime_call(RC_LEAF, OptoRuntime::osr_end_Type(),
 324                     CAST_FROM_FN_PTR(address, SharedRuntime::OSR_migration_end),
 325                     "OSR_migration_end", TypeRawPtr::BOTTOM,
 326                     osr_buf);
 327 
 328   // Now that the interpreter state is loaded, make sure it will match
 329   // at execution time what the compiler is expecting now:
 330   SafePointNode* bad_type_exit = clone_map();
 331   bad_type_exit->set_control(new RegionNode(1));
 332 
 333   assert(osr_block->flow()->jsrs()->size() == 0, "should be no jsrs live at osr point");
 334   for (index = 0; index < max_locals; index++) {
 335     if (stopped())  break;
 336     Node* l = local(index);
 337     if (l->is_top())  continue;  // nothing here
 338     const Type *type = osr_block->local_type_at(index);
 339     if (type->isa_oopptr() != NULL) {
 340       if (!live_oops.at(index)) {
 341         // skip type check for dead oops
 342         continue;
 343       }
 344     }
 345     if (osr_block->flow()->local_type_at(index)->is_return_address()) {
 346       // In our current system it's illegal for jsr addresses to be
 347       // live into an OSR entry point because the compiler performs
 348       // inlining of jsrs.  ciTypeFlow has a bailout that detect this
 349       // case and aborts the compile if addresses are live into an OSR
 350       // entry point.  Because of that we can assume that any address
 351       // locals at the OSR entry point are dead.  Method liveness
 352       // isn't precise enought to figure out that they are dead in all
 353       // cases so simply skip checking address locals all
 354       // together. Any type check is guaranteed to fail since the
 355       // interpreter type is the result of a load which might have any
 356       // value and the expected type is a constant.
 357       continue;
 358     }
 359     set_local(index, check_interpreter_type(l, type, bad_type_exit));
 360   }
 361 
 362   for (index = 0; index < sp(); index++) {
 363     if (stopped())  break;
 364     Node* l = stack(index);
 365     if (l->is_top())  continue;  // nothing here
 366     const Type *type = osr_block->stack_type_at(index);
 367     set_stack(index, check_interpreter_type(l, type, bad_type_exit));
 368   }
 369 
 370   if (bad_type_exit->control()->req() > 1) {
 371     // Build an uncommon trap here, if any inputs can be unexpected.
 372     bad_type_exit->set_control(_gvn.transform( bad_type_exit->control() ));
 373     record_for_igvn(bad_type_exit->control());
 374     SafePointNode* types_are_good = map();
 375     set_map(bad_type_exit);
 376     // The unexpected type happens because a new edge is active
 377     // in the CFG, which typeflow had previously ignored.
 378     // E.g., Object x = coldAtFirst() && notReached()? "str": new Integer(123).
 379     // This x will be typed as Integer if notReached is not yet linked.
 380     // It could also happen due to a problem in ciTypeFlow analysis.
 381     uncommon_trap(Deoptimization::Reason_constraint,
 382                   Deoptimization::Action_reinterpret);
 383     set_map(types_are_good);
 384   }
 385 }
 386 
 387 //------------------------------Parse------------------------------------------
 388 // Main parser constructor.
 389 Parse::Parse(JVMState* caller, ciMethod* parse_method, float expected_uses)
 390   : _exits(caller)
 391 {
 392   // Init some variables
 393   _caller = caller;
 394   _method = parse_method;
 395   _expected_uses = expected_uses;
 396   _depth = 1 + (caller->has_method() ? caller->depth() : 0);
 397   _wrote_final = false;
 398   _wrote_volatile = false;
 399   _wrote_stable = false;
 400   _wrote_fields = false;
 401   _alloc_with_final = NULL;
 402   _entry_bci = InvocationEntryBci;
 403   _tf = NULL;
 404   _block = NULL;
 405   _first_return = true;
 406   _replaced_nodes_for_exceptions = false;
 407   _new_idx = C->unique();
 408   debug_only(_block_count = -1);
 409   debug_only(_blocks = (Block*)-1);
 410 #ifndef PRODUCT
 411   if (PrintCompilation || PrintOpto) {
 412     // Make sure I have an inline tree, so I can print messages about it.
 413     JVMState* ilt_caller = is_osr_parse() ? caller->caller() : caller;
 414     InlineTree::find_subtree_from_root(C->ilt(), ilt_caller, parse_method);
 415   }
 416   _max_switch_depth = 0;
 417   _est_switch_depth = 0;
 418 #endif
 419 
 420   if (parse_method->has_reserved_stack_access()) {
 421     C->set_has_reserved_stack_access(true);
 422   }
 423 
 424   _tf = TypeFunc::make(method());
 425   _iter.reset_to_method(method());
 426   _flow = method()->get_flow_analysis();
 427   if (_flow->failing()) {
 428     C->record_method_not_compilable(_flow->failure_reason());
 429   }
 430 
 431 #ifndef PRODUCT
 432   if (_flow->has_irreducible_entry()) {
 433     C->set_parsed_irreducible_loop(true);
 434   }
 435 #endif
 436 
 437   if (_expected_uses <= 0) {
 438     _prof_factor = 1;
 439   } else {
 440     float prof_total = parse_method->interpreter_invocation_count();
 441     if (prof_total <= _expected_uses) {
 442       _prof_factor = 1;
 443     } else {
 444       _prof_factor = _expected_uses / prof_total;
 445     }
 446   }
 447 
 448   CompileLog* log = C->log();
 449   if (log != NULL) {
 450     log->begin_head("parse method='%d' uses='%f'",
 451                     log->identify(parse_method), expected_uses);
 452     if (depth() == 1 && C->is_osr_compilation()) {
 453       log->print(" osr_bci='%d'", C->entry_bci());
 454     }
 455     log->stamp();
 456     log->end_head();
 457   }
 458 
 459   // Accumulate deoptimization counts.
 460   // (The range_check and store_check counts are checked elsewhere.)
 461   ciMethodData* md = method()->method_data();
 462   for (uint reason = 0; reason < md->trap_reason_limit(); reason++) {
 463     uint md_count = md->trap_count(reason);
 464     if (md_count != 0) {
 465       if (md_count == md->trap_count_limit())
 466         md_count += md->overflow_trap_count();
 467       uint total_count = C->trap_count(reason);
 468       uint old_count   = total_count;
 469       total_count += md_count;
 470       // Saturate the add if it overflows.
 471       if (total_count < old_count || total_count < md_count)
 472         total_count = (uint)-1;
 473       C->set_trap_count(reason, total_count);
 474       if (log != NULL)
 475         log->elem("observe trap='%s' count='%d' total='%d'",
 476                   Deoptimization::trap_reason_name(reason),
 477                   md_count, total_count);
 478     }
 479   }
 480   // Accumulate total sum of decompilations, also.
 481   C->set_decompile_count(C->decompile_count() + md->decompile_count());
 482 
 483   _count_invocations = C->do_count_invocations();
 484   _method_data_update = C->do_method_data_update();
 485 
 486   if (log != NULL && method()->has_exception_handlers()) {
 487     log->elem("observe that='has_exception_handlers'");
 488   }
 489 
 490   assert(method()->can_be_compiled(),       "Can not parse this method, cutout earlier");
 491   assert(method()->has_balanced_monitors(), "Can not parse unbalanced monitors, cutout earlier");
 492 
 493   // Always register dependence if JVMTI is enabled, because
 494   // either breakpoint setting or hotswapping of methods may
 495   // cause deoptimization.
 496   if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
 497     C->dependencies()->assert_evol_method(method());
 498   }
 499 
 500   NOT_PRODUCT(methods_seen++);
 501 
 502   // Do some special top-level things.
 503   if (depth() == 1 && C->is_osr_compilation()) {
 504     _entry_bci = C->entry_bci();
 505     _flow = method()->get_osr_flow_analysis(osr_bci());
 506     if (_flow->failing()) {
 507       C->record_method_not_compilable(_flow->failure_reason());
 508 #ifndef PRODUCT
 509       if (PrintOpto && (Verbose || WizardMode)) {
 510         tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
 511         if (Verbose) {
 512           method()->print();
 513           method()->print_codes();
 514           _flow->print();
 515         }
 516       }
 517 #endif
 518     }
 519     _tf = C->tf();     // the OSR entry type is different
 520   }
 521 
 522 #ifdef ASSERT
 523   if (depth() == 1) {
 524     assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");
 525     if (C->tf() != tf()) {
 526       MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
 527       assert(C->env()->system_dictionary_modification_counter_changed(),
 528              "Must invalidate if TypeFuncs differ");
 529     }
 530   } else {
 531     assert(!this->is_osr_parse(), "no recursive OSR");
 532   }
 533 #endif
 534 
 535 #ifndef PRODUCT
 536   methods_parsed++;
 537   // add method size here to guarantee that inlined methods are added too
 538   if (CITime)
 539     _total_bytes_compiled += method()->code_size();
 540 
 541   show_parse_info();
 542 #endif
 543 
 544   if (failing()) {
 545     if (log)  log->done("parse");
 546     return;
 547   }
 548 
 549   gvn().set_type(root(), root()->bottom_type());
 550   gvn().transform(top());
 551 
 552   // Import the results of the ciTypeFlow.
 553   init_blocks();
 554 
 555   // Merge point for all normal exits
 556   build_exits();
 557 
 558   // Setup the initial JVM state map.
 559   SafePointNode* entry_map = create_entry_map();
 560 
 561   // Check for bailouts during map initialization
 562   if (failing() || entry_map == NULL) {
 563     if (log)  log->done("parse");
 564     return;
 565   }
 566 
 567   Node_Notes* caller_nn = C->default_node_notes();
 568   // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
 569   if (DebugInlinedCalls || depth() == 1) {
 570     C->set_default_node_notes(make_node_notes(caller_nn));
 571   }
 572 
 573   if (is_osr_parse()) {
 574     Node* osr_buf = entry_map->in(TypeFunc::Parms+0);
 575     entry_map->set_req(TypeFunc::Parms+0, top());
 576     set_map(entry_map);
 577     load_interpreter_state(osr_buf);
 578   } else {
 579     set_map(entry_map);
 580     do_method_entry();
 581     if (depth() == 1 && C->age_code()) {
 582       decrement_age();
 583     }
 584   }
 585 
 586   if (depth() == 1 && !failing()) {
 587     // Add check to deoptimize the nmethod if RTM state was changed
 588     rtm_deopt();
 589   }
 590 
 591   // Check for bailouts during method entry or RTM state check setup.
 592   if (failing()) {
 593     if (log)  log->done("parse");
 594     C->set_default_node_notes(caller_nn);
 595     return;
 596   }
 597 
 598   entry_map = map();  // capture any changes performed by method setup code
 599   assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");
 600 
 601   // We begin parsing as if we have just encountered a jump to the
 602   // method entry.
 603   Block* entry_block = start_block();
 604   assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
 605   set_map_clone(entry_map);
 606   merge_common(entry_block, entry_block->next_path_num());
 607 
 608 #ifndef PRODUCT
 609   BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
 610   set_parse_histogram( parse_histogram_obj );
 611 #endif
 612 
 613   // Parse all the basic blocks.
 614   do_all_blocks();
 615 
 616   C->set_default_node_notes(caller_nn);
 617 
 618   // Check for bailouts during conversion to graph
 619   if (failing()) {
 620     if (log)  log->done("parse");
 621     return;
 622   }
 623 
 624   // Fix up all exiting control flow.
 625   set_map(entry_map);
 626   do_exits();
 627 
 628   if (log)  log->done("parse nodes='%d' live='%d' memory='" SIZE_FORMAT "'",
 629                       C->unique(), C->live_nodes(), C->node_arena()->used());
 630 }
 631 
 632 //---------------------------do_all_blocks-------------------------------------
 633 void Parse::do_all_blocks() {
 634   bool has_irreducible = flow()->has_irreducible_entry();
 635 
 636   // Walk over all blocks in Reverse Post-Order.
 637   while (true) {
 638     bool progress = false;
 639     for (int rpo = 0; rpo < block_count(); rpo++) {
 640       Block* block = rpo_at(rpo);
 641 
 642       if (block->is_parsed()) continue;
 643 
 644       if (!block->is_merged()) {
 645         // Dead block, no state reaches this block
 646         continue;
 647       }
 648 
 649       // Prepare to parse this block.
 650       load_state_from(block);
 651 
 652       if (stopped()) {
 653         // Block is dead.
 654         continue;
 655       }
 656 
 657       NOT_PRODUCT(blocks_parsed++);
 658 
 659       progress = true;
 660       if (block->is_loop_head() || block->is_handler() || has_irreducible && !block->is_ready()) {
 661         // Not all preds have been parsed.  We must build phis everywhere.
 662         // (Note that dead locals do not get phis built, ever.)
 663         ensure_phis_everywhere();
 664 
 665         if (block->is_SEL_head()) {
 666           // Add predicate to single entry (not irreducible) loop head.
 667           assert(!block->has_merged_backedge(), "only entry paths should be merged for now");
 668           // Need correct bci for predicate.
 669           // It is fine to set it here since do_one_block() will set it anyway.
 670           set_parse_bci(block->start());
 671           add_predicate();
 672           // Add new region for back branches.
 673           int edges = block->pred_count() - block->preds_parsed() + 1; // +1 for original region
 674           RegionNode *r = new RegionNode(edges+1);
 675           _gvn.set_type(r, Type::CONTROL);
 676           record_for_igvn(r);
 677           r->init_req(edges, control());
 678           set_control(r);
 679           // Add new phis.
 680           ensure_phis_everywhere();
 681         }
 682 
 683         // Leave behind an undisturbed copy of the map, for future merges.
 684         set_map(clone_map());
 685       }
 686 
 687       if (control()->is_Region() && !block->is_loop_head() && !has_irreducible && !block->is_handler()) {
 688         // In the absence of irreducible loops, the Region and Phis
 689         // associated with a merge that doesn't involve a backedge can
 690         // be simplified now since the RPO parsing order guarantees
 691         // that any path which was supposed to reach here has already
 692         // been parsed or must be dead.
 693         Node* c = control();
 694         Node* result = _gvn.transform_no_reclaim(control());
 695         if (c != result && TraceOptoParse) {
 696           tty->print_cr("Block #%d replace %d with %d", block->rpo(), c->_idx, result->_idx);
 697         }
 698         if (result != top()) {
 699           record_for_igvn(result);
 700         }
 701       }
 702 
 703       // Parse the block.
 704       do_one_block();
 705 
 706       // Check for bailouts.
 707       if (failing())  return;
 708     }
 709 
 710     // with irreducible loops multiple passes might be necessary to parse everything
 711     if (!has_irreducible || !progress) {
 712       break;
 713     }
 714   }
 715 
 716 #ifndef PRODUCT
 717   blocks_seen += block_count();
 718 
 719   // Make sure there are no half-processed blocks remaining.
 720   // Every remaining unprocessed block is dead and may be ignored now.
 721   for (int rpo = 0; rpo < block_count(); rpo++) {
 722     Block* block = rpo_at(rpo);
 723     if (!block->is_parsed()) {
 724       if (TraceOptoParse) {
 725         tty->print_cr("Skipped dead block %d at bci:%d", rpo, block->start());
 726       }
 727       assert(!block->is_merged(), "no half-processed blocks");
 728     }
 729   }
 730 #endif
 731 }
 732 
 733 static Node* mask_int_value(Node* v, BasicType bt, PhaseGVN* gvn) {
 734   switch (bt) {
 735   case T_BYTE:
 736     v = gvn->transform(new LShiftINode(v, gvn->intcon(24)));
 737     v = gvn->transform(new RShiftINode(v, gvn->intcon(24)));
 738     break;
 739   case T_SHORT:
 740     v = gvn->transform(new LShiftINode(v, gvn->intcon(16)));
 741     v = gvn->transform(new RShiftINode(v, gvn->intcon(16)));
 742     break;
 743   case T_CHAR:
 744     v = gvn->transform(new AndINode(v, gvn->intcon(0xFFFF)));
 745     break;
 746   case T_BOOLEAN:
 747     v = gvn->transform(new AndINode(v, gvn->intcon(0x1)));
 748     break;
 749   }
 750   return v;
 751 }
 752 
 753 //-------------------------------build_exits----------------------------------
 754 // Build normal and exceptional exit merge points.
 755 void Parse::build_exits() {
 756   // make a clone of caller to prevent sharing of side-effects
 757   _exits.set_map(_exits.clone_map());
 758   _exits.clean_stack(_exits.sp());
 759   _exits.sync_jvms();
 760 
 761   RegionNode* region = new RegionNode(1);
 762   record_for_igvn(region);
 763   gvn().set_type_bottom(region);
 764   _exits.set_control(region);
 765 
 766   // Note:  iophi and memphi are not transformed until do_exits.
 767   Node* iophi  = new PhiNode(region, Type::ABIO);
 768   Node* memphi = new PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
 769   gvn().set_type_bottom(iophi);
 770   gvn().set_type_bottom(memphi);
 771   _exits.set_i_o(iophi);
 772   _exits.set_all_memory(memphi);
 773 
 774   // Add a return value to the exit state.  (Do not push it yet.)
 775   if (tf()->range()->cnt() > TypeFunc::Parms) {
 776     const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
 777     if (ret_type->isa_int()) {
 778       BasicType ret_bt = method()->return_type()->basic_type();
 779       if (ret_bt == T_BOOLEAN ||
 780           ret_bt == T_CHAR ||
 781           ret_bt == T_BYTE ||
 782           ret_bt == T_SHORT) {
 783         ret_type = TypeInt::INT;
 784       }
 785     }
 786 
 787     // Don't "bind" an unloaded return klass to the ret_phi. If the klass
 788     // becomes loaded during the subsequent parsing, the loaded and unloaded
 789     // types will not join when we transform and push in do_exits().
 790     const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
 791     if (ret_oop_type && !ret_oop_type->klass()->is_loaded()) {
 792       ret_type = TypeOopPtr::BOTTOM;
 793     }
 794     int         ret_size = type2size[ret_type->basic_type()];
 795     Node*       ret_phi  = new PhiNode(region, ret_type);
 796     gvn().set_type_bottom(ret_phi);
 797     _exits.ensure_stack(ret_size);
 798     assert((int)(tf()->range()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
 799     assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
 800     _exits.set_argument(0, ret_phi);  // here is where the parser finds it
 801     // Note:  ret_phi is not yet pushed, until do_exits.
 802   }
 803 }
 804 
 805 
 806 //----------------------------build_start_state-------------------------------
 807 // Construct a state which contains only the incoming arguments from an
 808 // unknown caller.  The method & bci will be NULL & InvocationEntryBci.
 809 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
 810   int        arg_size = tf->domain()->cnt();
 811   int        max_size = MAX2(arg_size, (int)tf->range()->cnt());
 812   JVMState*  jvms     = new (this) JVMState(max_size - TypeFunc::Parms);
 813   SafePointNode* map  = new SafePointNode(max_size, NULL);
 814   record_for_igvn(map);
 815   assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
 816   Node_Notes* old_nn = default_node_notes();
 817   if (old_nn != NULL && has_method()) {
 818     Node_Notes* entry_nn = old_nn->clone(this);
 819     JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
 820     entry_jvms->set_offsets(0);
 821     entry_jvms->set_bci(entry_bci());
 822     entry_nn->set_jvms(entry_jvms);
 823     set_default_node_notes(entry_nn);
 824   }
 825   uint i;
 826   for (i = 0; i < (uint)arg_size; i++) {
 827     Node* parm = initial_gvn()->transform(new ParmNode(start, i));
 828     map->init_req(i, parm);
 829     // Record all these guys for later GVN.
 830     record_for_igvn(parm);
 831   }
 832   for (; i < map->req(); i++) {
 833     map->init_req(i, top());
 834   }
 835   assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
 836   set_default_node_notes(old_nn);
 837   map->set_jvms(jvms);
 838   jvms->set_map(map);
 839   return jvms;
 840 }
 841 
 842 //-----------------------------make_node_notes---------------------------------
 843 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
 844   if (caller_nn == NULL)  return NULL;
 845   Node_Notes* nn = caller_nn->clone(C);
 846   JVMState* caller_jvms = nn->jvms();
 847   JVMState* jvms = new (C) JVMState(method(), caller_jvms);
 848   jvms->set_offsets(0);
 849   jvms->set_bci(_entry_bci);
 850   nn->set_jvms(jvms);
 851   return nn;
 852 }
 853 
 854 
 855 //--------------------------return_values--------------------------------------
 856 void Compile::return_values(JVMState* jvms) {
 857   GraphKit kit(jvms);
 858   Node* ret = new ReturnNode(TypeFunc::Parms,
 859                              kit.control(),
 860                              kit.i_o(),
 861                              kit.reset_memory(),
 862                              kit.frameptr(),
 863                              kit.returnadr());
 864   // Add zero or 1 return values
 865   int ret_size = tf()->range()->cnt() - TypeFunc::Parms;
 866   if (ret_size > 0) {
 867     kit.inc_sp(-ret_size);  // pop the return value(s)
 868     kit.sync_jvms();
 869     ret->add_req(kit.argument(0));
 870     // Note:  The second dummy edge is not needed by a ReturnNode.
 871   }
 872   // bind it to root
 873   root()->add_req(ret);
 874   record_for_igvn(ret);
 875   initial_gvn()->transform_no_reclaim(ret);
 876 }
 877 
 878 //------------------------rethrow_exceptions-----------------------------------
 879 // Bind all exception states in the list into a single RethrowNode.
 880 void Compile::rethrow_exceptions(JVMState* jvms) {
 881   GraphKit kit(jvms);
 882   if (!kit.has_exceptions())  return;  // nothing to generate
 883   // Load my combined exception state into the kit, with all phis transformed:
 884   SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
 885   Node* ex_oop = kit.use_exception_state(ex_map);
 886   RethrowNode* exit = new RethrowNode(kit.control(),
 887                                       kit.i_o(), kit.reset_memory(),
 888                                       kit.frameptr(), kit.returnadr(),
 889                                       // like a return but with exception input
 890                                       ex_oop);
 891   // bind to root
 892   root()->add_req(exit);
 893   record_for_igvn(exit);
 894   initial_gvn()->transform_no_reclaim(exit);
 895 }
 896 
 897 //---------------------------do_exceptions-------------------------------------
 898 // Process exceptions arising from the current bytecode.
 899 // Send caught exceptions to the proper handler within this method.
 900 // Unhandled exceptions feed into _exit.
 901 void Parse::do_exceptions() {
 902   if (!has_exceptions())  return;
 903 
 904   if (failing()) {
 905     // Pop them all off and throw them away.
 906     while (pop_exception_state() != NULL) ;
 907     return;
 908   }
 909 
 910   PreserveJVMState pjvms(this, false);
 911 
 912   SafePointNode* ex_map;
 913   while ((ex_map = pop_exception_state()) != NULL) {
 914     if (!method()->has_exception_handlers()) {
 915       // Common case:  Transfer control outward.
 916       // Doing it this early allows the exceptions to common up
 917       // even between adjacent method calls.
 918       throw_to_exit(ex_map);
 919     } else {
 920       // Have to look at the exception first.
 921       assert(stopped(), "catch_inline_exceptions trashes the map");
 922       catch_inline_exceptions(ex_map);
 923       stop_and_kill_map();      // we used up this exception state; kill it
 924     }
 925   }
 926 
 927   // We now return to our regularly scheduled program:
 928 }
 929 
 930 //---------------------------throw_to_exit-------------------------------------
 931 // Merge the given map into an exception exit from this method.
 932 // The exception exit will handle any unlocking of receiver.
 933 // The ex_oop must be saved within the ex_map, unlike merge_exception.
 934 void Parse::throw_to_exit(SafePointNode* ex_map) {
 935   // Pop the JVMS to (a copy of) the caller.
 936   GraphKit caller;
 937   caller.set_map_clone(_caller->map());
 938   caller.set_bci(_caller->bci());
 939   caller.set_sp(_caller->sp());
 940   // Copy out the standard machine state:
 941   for (uint i = 0; i < TypeFunc::Parms; i++) {
 942     caller.map()->set_req(i, ex_map->in(i));
 943   }
 944   if (ex_map->has_replaced_nodes()) {
 945     _replaced_nodes_for_exceptions = true;
 946   }
 947   caller.map()->transfer_replaced_nodes_from(ex_map, _new_idx);
 948   // ...and the exception:
 949   Node*          ex_oop        = saved_ex_oop(ex_map);
 950   SafePointNode* caller_ex_map = caller.make_exception_state(ex_oop);
 951   // Finally, collect the new exception state in my exits:
 952   _exits.add_exception_state(caller_ex_map);
 953 }
 954 
 955 //------------------------------do_exits---------------------------------------
 956 void Parse::do_exits() {
 957   set_parse_bci(InvocationEntryBci);
 958 
 959   // Now peephole on the return bits
 960   Node* region = _exits.control();
 961   _exits.set_control(gvn().transform(region));
 962 
 963   Node* iophi = _exits.i_o();
 964   _exits.set_i_o(gvn().transform(iophi));
 965 
 966   // Figure out if we need to emit the trailing barrier. The barrier is only
 967   // needed in the constructors, and only in three cases:
 968   //
 969   // 1. The constructor wrote a final. The effects of all initializations
 970   //    must be committed to memory before any code after the constructor
 971   //    publishes the reference to the newly constructed object. Rather
 972   //    than wait for the publication, we simply block the writes here.
 973   //    Rather than put a barrier on only those writes which are required
 974   //    to complete, we force all writes to complete.
 975   //
 976   // 2. On PPC64, also add MemBarRelease for constructors which write
 977   //    volatile fields. As support_IRIW_for_not_multiple_copy_atomic_cpu
 978   //    is set on PPC64, no sync instruction is issued after volatile
 979   //    stores. We want to guarantee the same behavior as on platforms
 980   //    with total store order, although this is not required by the Java
 981   //    memory model. So as with finals, we add a barrier here.
 982   //
 983   // 3. Experimental VM option is used to force the barrier if any field
 984   //    was written out in the constructor.
 985   //
 986   // "All bets are off" unless the first publication occurs after a
 987   // normal return from the constructor.  We do not attempt to detect
 988   // such unusual early publications.  But no barrier is needed on
 989   // exceptional returns, since they cannot publish normally.
 990   //
 991   if (method()->is_initializer() &&
 992         (wrote_final() ||
 993            PPC64_ONLY(wrote_volatile() ||)
 994            (AlwaysSafeConstructors && wrote_fields()))) {
 995     _exits.insert_mem_bar(Opcodes::Op_MemBarRelease, alloc_with_final());
 996 
 997     // If Memory barrier is created for final fields write
 998     // and allocation node does not escape the initialize method,
 999     // then barrier introduced by allocation node can be removed.
1000     if (DoEscapeAnalysis && alloc_with_final()) {
1001       AllocateNode *alloc = AllocateNode::Ideal_allocation(alloc_with_final(), &_gvn);
1002       alloc->compute_MemBar_redundancy(method());
1003     }
1004     if (PrintOpto && (Verbose || WizardMode)) {
1005       method()->print_name();
1006       tty->print_cr(" writes finals and needs a memory barrier");
1007     }
1008   }
1009 
1010   // Any method can write a @Stable field; insert memory barriers
1011   // after those also. Can't bind predecessor allocation node (if any)
1012   // with barrier because allocation doesn't always dominate
1013   // MemBarRelease.
1014   if (wrote_stable()) {
1015     _exits.insert_mem_bar(Opcodes::Op_MemBarRelease);
1016     if (PrintOpto && (Verbose || WizardMode)) {
1017       method()->print_name();
1018       tty->print_cr(" writes @Stable and needs a memory barrier");
1019     }
1020   }
1021 
1022   for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
1023     // transform each slice of the original memphi:
1024     mms.set_memory(_gvn.transform(mms.memory()));
1025   }
1026 
1027   if (tf()->range()->cnt() > TypeFunc::Parms) {
1028     const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
1029     Node*       ret_phi  = _gvn.transform( _exits.argument(0) );
1030     if (!_exits.control()->is_top() && _gvn.type(ret_phi)->empty()) {
1031       // In case of concurrent class loading, the type we set for the
1032       // ret_phi in build_exits() may have been too optimistic and the
1033       // ret_phi may be top now.
1034       // Otherwise, we've encountered an error and have to mark the method as
1035       // not compilable. Just using an assertion instead would be dangerous
1036       // as this could lead to an infinite compile loop in non-debug builds.
1037       {
1038         MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
1039         if (C->env()->system_dictionary_modification_counter_changed()) {
1040           C->record_failure(C2Compiler::retry_class_loading_during_parsing());
1041         } else {
1042           C->record_method_not_compilable("Can't determine return type.");
1043         }
1044       }
1045       return;
1046     }
1047     if (ret_type->isa_int()) {
1048       BasicType ret_bt = method()->return_type()->basic_type();
1049       ret_phi = mask_int_value(ret_phi, ret_bt, &_gvn);
1050     }
1051     _exits.push_node(ret_type->basic_type(), ret_phi);
1052   }
1053 
1054   // Note:  Logic for creating and optimizing the ReturnNode is in Compile.
1055 
1056   // Unlock along the exceptional paths.
1057   // This is done late so that we can common up equivalent exceptions
1058   // (e.g., null checks) arising from multiple points within this method.
1059   // See GraphKit::add_exception_state, which performs the commoning.
1060   bool do_synch = method()->is_synchronized() && GenerateSynchronizationCode;
1061 
1062   // record exit from a method if compiled while Dtrace is turned on.
1063   if (do_synch || C->env()->dtrace_method_probes() || _replaced_nodes_for_exceptions) {
1064     // First move the exception list out of _exits:
1065     GraphKit kit(_exits.transfer_exceptions_into_jvms());
1066     SafePointNode* normal_map = kit.map();  // keep this guy safe
1067     // Now re-collect the exceptions into _exits:
1068     SafePointNode* ex_map;
1069     while ((ex_map = kit.pop_exception_state()) != NULL) {
1070       Node* ex_oop = kit.use_exception_state(ex_map);
1071       // Force the exiting JVM state to have this method at InvocationEntryBci.
1072       // The exiting JVM state is otherwise a copy of the calling JVMS.
1073       JVMState* caller = kit.jvms();
1074       JVMState* ex_jvms = caller->clone_shallow(C);
1075       ex_jvms->set_map(kit.clone_map());
1076       ex_jvms->map()->set_jvms(ex_jvms);
1077       ex_jvms->set_bci(   InvocationEntryBci);
1078       kit.set_jvms(ex_jvms);
1079       if (do_synch) {
1080         // Add on the synchronized-method box/object combo
1081         kit.map()->push_monitor(_synch_lock);
1082         // Unlock!
1083         kit.shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
1084       }
1085       if (C->env()->dtrace_method_probes()) {
1086         kit.make_dtrace_method_exit(method());
1087       }
1088       if (_replaced_nodes_for_exceptions) {
1089         kit.map()->apply_replaced_nodes();
1090       }
1091       // Done with exception-path processing.
1092       ex_map = kit.make_exception_state(ex_oop);
1093       assert(ex_jvms->same_calls_as(ex_map->jvms()), "sanity");
1094       // Pop the last vestige of this method:
1095       ex_map->set_jvms(caller->clone_shallow(C));
1096       ex_map->jvms()->set_map(ex_map);
1097       _exits.push_exception_state(ex_map);
1098     }
1099     assert(_exits.map() == normal_map, "keep the same return state");
1100   }
1101 
1102   {
1103     // Capture very early exceptions (receiver null checks) from caller JVMS
1104     GraphKit caller(_caller);
1105     SafePointNode* ex_map;
1106     while ((ex_map = caller.pop_exception_state()) != NULL) {
1107       _exits.add_exception_state(ex_map);
1108     }
1109   }
1110   _exits.map()->apply_replaced_nodes();
1111 }
1112 
1113 //-----------------------------create_entry_map-------------------------------
1114 // Initialize our parser map to contain the types at method entry.
1115 // For OSR, the map contains a single RawPtr parameter.
1116 // Initial monitor locking for sync. methods is performed by do_method_entry.
1117 SafePointNode* Parse::create_entry_map() {
1118   // Check for really stupid bail-out cases.
1119   uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
1120   if (len >= 32760) {
1121     C->record_method_not_compilable("too many local variables");
1122     return NULL;
1123   }
1124 
1125   // clear current replaced nodes that are of no use from here on (map was cloned in build_exits).
1126   _caller->map()->delete_replaced_nodes();
1127 
1128   // If this is an inlined method, we may have to do a receiver null check.
1129   if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
1130     GraphKit kit(_caller);
1131     kit.null_check_receiver_before_call(method());
1132     _caller = kit.transfer_exceptions_into_jvms();
1133     if (kit.stopped()) {
1134       _exits.add_exception_states_from(_caller);
1135       _exits.set_jvms(_caller);
1136       return NULL;
1137     }
1138   }
1139 
1140   assert(method() != NULL, "parser must have a method");
1141 
1142   // Create an initial safepoint to hold JVM state during parsing
1143   JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : NULL);
1144   set_map(new SafePointNode(len, jvms));
1145   jvms->set_map(map());
1146   record_for_igvn(map());
1147   assert(jvms->endoff() == len, "correct jvms sizing");
1148 
1149   SafePointNode* inmap = _caller->map();
1150   assert(inmap != NULL, "must have inmap");
1151   // In case of null check on receiver above
1152   map()->transfer_replaced_nodes_from(inmap, _new_idx);
1153 
1154   uint i;
1155 
1156   // Pass thru the predefined input parameters.
1157   for (i = 0; i < TypeFunc::Parms; i++) {
1158     map()->init_req(i, inmap->in(i));
1159   }
1160 
1161   if (depth() == 1) {
1162     assert(map()->memory()->Opcode() == Opcodes::Op_Parm, "");
1163     // Insert the memory aliasing node
1164     set_all_memory(reset_memory());
1165   }
1166   assert(merged_memory(), "");
1167 
1168   // Now add the locals which are initially bound to arguments:
1169   uint arg_size = tf()->domain()->cnt();
1170   ensure_stack(arg_size - TypeFunc::Parms);  // OSR methods have funny args
1171   for (i = TypeFunc::Parms; i < arg_size; i++) {
1172     map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
1173   }
1174 
1175   // Clear out the rest of the map (locals and stack)
1176   for (i = arg_size; i < len; i++) {
1177     map()->init_req(i, top());
1178   }
1179 
1180   SafePointNode* entry_map = stop();
1181   return entry_map;
1182 }
1183 
1184 //-----------------------------do_method_entry--------------------------------
1185 // Emit any code needed in the pseudo-block before BCI zero.
1186 // The main thing to do is lock the receiver of a synchronized method.
1187 void Parse::do_method_entry() {
1188   set_parse_bci(InvocationEntryBci); // Pseudo-BCP
1189   set_sp(0);                      // Java Stack Pointer
1190 
1191   NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
1192 
1193   if (C->env()->dtrace_method_probes()) {
1194     make_dtrace_method_entry(method());
1195   }
1196 
1197   // If the method is synchronized, we need to construct a lock node, attach
1198   // it to the Start node, and pin it there.
1199   if (method()->is_synchronized()) {
1200     // Insert a FastLockNode right after the Start which takes as arguments
1201     // the current thread pointer, the "this" pointer & the address of the
1202     // stack slot pair used for the lock.  The "this" pointer is a projection
1203     // off the start node, but the locking spot has to be constructed by
1204     // creating a ConLNode of 0, and boxing it with a BoxLockNode.  The BoxLockNode
1205     // becomes the second argument to the FastLockNode call.  The
1206     // FastLockNode becomes the new control parent to pin it to the start.
1207 
1208     // Setup Object Pointer
1209     Node *lock_obj = NULL;
1210     if(method()->is_static()) {
1211       ciInstance* mirror = _method->holder()->java_mirror();
1212       const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1213       lock_obj = makecon(t_lock);
1214     } else {                  // Else pass the "this" pointer,
1215       lock_obj = local(0);    // which is Parm0 from StartNode
1216     }
1217     // Clear out dead values from the debug info.
1218     kill_dead_locals();
1219     // Build the FastLockNode
1220     _synch_lock = shared_lock(lock_obj);
1221   }
1222 
1223   // Feed profiling data for parameters to the type system so it can
1224   // propagate it as speculative types
1225   record_profiled_parameters_for_speculation();
1226 
1227   if (depth() == 1) {
1228     increment_and_test_invocation_counter(Tier2CompileThreshold);
1229   }
1230 }
1231 
1232 //------------------------------init_blocks------------------------------------
1233 // Initialize our parser map to contain the types/monitors at method entry.
1234 void Parse::init_blocks() {
1235   // Create the blocks.
1236   _block_count = flow()->block_count();
1237   _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);
1238 
1239   // Initialize the structs.
1240   for (int rpo = 0; rpo < block_count(); rpo++) {
1241     Block* block = rpo_at(rpo);
1242     new(block) Block(this, rpo);
1243   }
1244 
1245   // Collect predecessor and successor information.
1246   for (int rpo = 0; rpo < block_count(); rpo++) {
1247     Block* block = rpo_at(rpo);
1248     block->init_graph(this);
1249   }
1250 }
1251 
1252 //-------------------------------init_node-------------------------------------
1253 Parse::Block::Block(Parse* outer, int rpo) : _live_locals() {
1254   _flow = outer->flow()->rpo_at(rpo);
1255   _pred_count = 0;
1256   _preds_parsed = 0;
1257   _count = 0;
1258   _is_parsed = false;
1259   _is_handler = false;
1260   _has_merged_backedge = false;
1261   _start_map = NULL;
1262   _num_successors = 0;
1263   _all_successors = 0;
1264   _successors = NULL;
1265   assert(pred_count() == 0 && preds_parsed() == 0, "sanity");
1266   assert(!(is_merged() || is_parsed() || is_handler() || has_merged_backedge()), "sanity");
1267   assert(_live_locals.size() == 0, "sanity");
1268 
1269   // entry point has additional predecessor
1270   if (flow()->is_start())  _pred_count++;
1271   assert(flow()->is_start() == (this == outer->start_block()), "");
1272 }
1273 
1274 //-------------------------------init_graph------------------------------------
1275 void Parse::Block::init_graph(Parse* outer) {
1276   // Create the successor list for this parser block.
1277   GrowableArray<ciTypeFlow::Block*>* tfs = flow()->successors();
1278   GrowableArray<ciTypeFlow::Block*>* tfe = flow()->exceptions();
1279   int ns = tfs->length();
1280   int ne = tfe->length();
1281   _num_successors = ns;
1282   _all_successors = ns+ne;
1283   _successors = (ns+ne == 0) ? NULL : NEW_RESOURCE_ARRAY(Block*, ns+ne);
1284   int p = 0;
1285   for (int i = 0; i < ns+ne; i++) {
1286     ciTypeFlow::Block* tf2 = (i < ns) ? tfs->at(i) : tfe->at(i-ns);
1287     Block* block2 = outer->rpo_at(tf2->rpo());
1288     _successors[i] = block2;
1289 
1290     // Accumulate pred info for the other block, too.
1291     if (i < ns) {
1292       block2->_pred_count++;
1293     } else {
1294       block2->_is_handler = true;
1295     }
1296 
1297     #ifdef ASSERT
1298     // A block's successors must be distinguishable by BCI.
1299     // That is, no bytecode is allowed to branch to two different
1300     // clones of the same code location.
1301     for (int j = 0; j < i; j++) {
1302       Block* block1 = _successors[j];
1303       if (block1 == block2)  continue;  // duplicates are OK
1304       assert(block1->start() != block2->start(), "successors have unique bcis");
1305     }
1306     #endif
1307   }
1308 
1309   // Note: We never call next_path_num along exception paths, so they
1310   // never get processed as "ready".  Also, the input phis of exception
1311   // handlers get specially processed, so that
1312 }
1313 
1314 //---------------------------successor_for_bci---------------------------------
1315 Parse::Block* Parse::Block::successor_for_bci(int bci) {
1316   for (int i = 0; i < all_successors(); i++) {
1317     Block* block2 = successor_at(i);
1318     if (block2->start() == bci)  return block2;
1319   }
1320   // We can actually reach here if ciTypeFlow traps out a block
1321   // due to an unloaded class, and concurrently with compilation the
1322   // class is then loaded, so that a later phase of the parser is
1323   // able to see more of the bytecode CFG.  Or, the flow pass and
1324   // the parser can have a minor difference of opinion about executability
1325   // of bytecodes.  For example, "obj.field = null" is executable even
1326   // if the field's type is an unloaded class; the flow pass used to
1327   // make a trap for such code.
1328   return NULL;
1329 }
1330 
1331 
1332 //-----------------------------stack_type_at-----------------------------------
1333 const Type* Parse::Block::stack_type_at(int i) const {
1334   return get_type(flow()->stack_type_at(i));
1335 }
1336 
1337 
1338 //-----------------------------local_type_at-----------------------------------
1339 const Type* Parse::Block::local_type_at(int i) const {
1340   // Make dead locals fall to bottom.
1341   if (_live_locals.size() == 0) {
1342     MethodLivenessResult live_locals = flow()->outer()->method()->liveness_at_bci(start());
1343     // This bitmap can be zero length if we saw a breakpoint.
1344     // In such cases, pretend they are all live.
1345     ((Block*)this)->_live_locals = live_locals;
1346   }
1347   if (_live_locals.size() > 0 && !_live_locals.at(i))
1348     return Type::BOTTOM;
1349 
1350   return get_type(flow()->local_type_at(i));
1351 }
1352 
1353 
1354 #ifndef PRODUCT
1355 
1356 //----------------------------name_for_bc--------------------------------------
1357 // helper method for BytecodeParseHistogram
1358 static const char* name_for_bc(int i) {
1359   return Bytecodes::is_defined(i) ? Bytecodes::name(Bytecodes::cast(i)) : "xxxunusedxxx";
1360 }
1361 
1362 //----------------------------BytecodeParseHistogram------------------------------------
1363 Parse::BytecodeParseHistogram::BytecodeParseHistogram(Parse *p, Compile *c) {
1364   _parser   = p;
1365   _compiler = c;
1366   if( ! _initialized ) { _initialized = true; reset(); }
1367 }
1368 
1369 //----------------------------current_count------------------------------------
1370 int Parse::BytecodeParseHistogram::current_count(BPHType bph_type) {
1371   switch( bph_type ) {
1372   case BPH_transforms: { return _parser->gvn().made_progress(); }
1373   case BPH_values:     { return _parser->gvn().made_new_values(); }
1374   default: { ShouldNotReachHere(); return 0; }
1375   }
1376 }
1377 
1378 //----------------------------initialized--------------------------------------
1379 bool Parse::BytecodeParseHistogram::initialized() { return _initialized; }
1380 
1381 //----------------------------reset--------------------------------------------
1382 void Parse::BytecodeParseHistogram::reset() {
1383   int i = Bytecodes::number_of_codes;
1384   while (i-- > 0) { _bytecodes_parsed[i] = 0; _nodes_constructed[i] = 0; _nodes_transformed[i] = 0; _new_values[i] = 0; }
1385 }
1386 
1387 //----------------------------set_initial_state--------------------------------
1388 // Record info when starting to parse one bytecode
1389 void Parse::BytecodeParseHistogram::set_initial_state( Bytecodes::Code bc ) {
1390   if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1391     _initial_bytecode    = bc;
1392     _initial_node_count  = _compiler->unique();
1393     _initial_transforms  = current_count(BPH_transforms);
1394     _initial_values      = current_count(BPH_values);
1395   }
1396 }
1397 
1398 //----------------------------record_change--------------------------------
1399 // Record results of parsing one bytecode
1400 void Parse::BytecodeParseHistogram::record_change() {
1401   if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1402     ++_bytecodes_parsed[_initial_bytecode];
1403     _nodes_constructed [_initial_bytecode] += (_compiler->unique() - _initial_node_count);
1404     _nodes_transformed [_initial_bytecode] += (current_count(BPH_transforms) - _initial_transforms);
1405     _new_values        [_initial_bytecode] += (current_count(BPH_values)     - _initial_values);
1406   }
1407 }
1408 
1409 
1410 //----------------------------print--------------------------------------------
1411 void Parse::BytecodeParseHistogram::print(float cutoff) {
1412   ResourceMark rm;
1413   // print profile
1414   int total  = 0;
1415   int i      = 0;
1416   for( i = 0; i < Bytecodes::number_of_codes; ++i ) { total += _bytecodes_parsed[i]; }
1417   int abs_sum = 0;
1418   tty->cr();   //0123456789012345678901234567890123456789012345678901234567890123456789
1419   tty->print_cr("Histogram of %d parsed bytecodes:", total);
1420   if( total == 0 ) { return; }
1421   tty->cr();
1422   tty->print_cr("absolute:  count of compiled bytecodes of this type");
1423   tty->print_cr("relative:  percentage contribution to compiled nodes");
1424   tty->print_cr("nodes   :  Average number of nodes constructed per bytecode");
1425   tty->print_cr("rnodes  :  Significance towards total nodes constructed, (nodes*relative)");
1426   tty->print_cr("transforms: Average amount of tranform progress per bytecode compiled");
1427   tty->print_cr("values  :  Average number of node values improved per bytecode");
1428   tty->print_cr("name    :  Bytecode name");
1429   tty->cr();
1430   tty->print_cr("  absolute  relative   nodes  rnodes  transforms  values   name");
1431   tty->print_cr("----------------------------------------------------------------------");
1432   while (--i > 0) {
1433     int       abs = _bytecodes_parsed[i];
1434     float     rel = abs * 100.0F / total;
1435     float   nodes = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_constructed[i])/_bytecodes_parsed[i];
1436     float  rnodes = _bytecodes_parsed[i] == 0 ? 0 :  rel * nodes;
1437     float  xforms = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_transformed[i])/_bytecodes_parsed[i];
1438     float  values = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _new_values       [i])/_bytecodes_parsed[i];
1439     if (cutoff <= rel) {
1440       tty->print_cr("%10d  %7.2f%%  %6.1f  %6.2f   %6.1f   %6.1f     %s", abs, rel, nodes, rnodes, xforms, values, name_for_bc(i));
1441       abs_sum += abs;
1442     }
1443   }
1444   tty->print_cr("----------------------------------------------------------------------");
1445   float rel_sum = abs_sum * 100.0F / total;
1446   tty->print_cr("%10d  %7.2f%%    (cutoff = %.2f%%)", abs_sum, rel_sum, cutoff);
1447   tty->print_cr("----------------------------------------------------------------------");
1448   tty->cr();
1449 }
1450 #endif
1451 
1452 //----------------------------load_state_from----------------------------------
1453 // Load block/map/sp.  But not do not touch iter/bci.
1454 void Parse::load_state_from(Block* block) {
1455   set_block(block);
1456   // load the block's JVM state:
1457   set_map(block->start_map());
1458   set_sp( block->start_sp());
1459 }
1460 
1461 
1462 //-----------------------------record_state------------------------------------
1463 void Parse::Block::record_state(Parse* p) {
1464   assert(!is_merged(), "can only record state once, on 1st inflow");
1465   assert(start_sp() == p->sp(), "stack pointer must agree with ciTypeFlow");
1466   set_start_map(p->stop());
1467 }
1468 
1469 
1470 //------------------------------do_one_block-----------------------------------
1471 void Parse::do_one_block() {
1472   if (TraceOptoParse) {
1473     Block *b = block();
1474     int ns = b->num_successors();
1475     int nt = b->all_successors();
1476 
1477     tty->print("Parsing block #%d at bci [%d,%d), successors: ",
1478                   block()->rpo(), block()->start(), block()->limit());
1479     for (int i = 0; i < nt; i++) {
1480       tty->print((( i < ns) ? " %d" : " %d(e)"), b->successor_at(i)->rpo());
1481     }
1482     if (b->is_loop_head()) tty->print("  lphd");
1483     tty->cr();
1484   }
1485 
1486   assert(block()->is_merged(), "must be merged before being parsed");
1487   block()->mark_parsed();
1488 
1489   // Set iterator to start of block.
1490   iter().reset_to_bci(block()->start());
1491 
1492   CompileLog* log = C->log();
1493 
1494   // Parse bytecodes
1495   while (!stopped() && !failing()) {
1496     iter().next();
1497 
1498     // Learn the current bci from the iterator:
1499     set_parse_bci(iter().cur_bci());
1500 
1501     if (bci() == block()->limit()) {
1502       // Do not walk into the next block until directed by do_all_blocks.
1503       merge(bci());
1504       break;
1505     }
1506     assert(bci() < block()->limit(), "bci still in block");
1507 
1508     if (log != NULL) {
1509       // Output an optional context marker, to help place actions
1510       // that occur during parsing of this BC.  If there is no log
1511       // output until the next context string, this context string
1512       // will be silently ignored.
1513       log->set_context("bc code='%d' bci='%d'", (int)bc(), bci());
1514     }
1515 
1516     if (block()->has_trap_at(bci())) {
1517       // We must respect the flow pass's traps, because it will refuse
1518       // to produce successors for trapping blocks.
1519       int trap_index = block()->flow()->trap_index();
1520       assert(trap_index != 0, "trap index must be valid");
1521       uncommon_trap(trap_index);
1522       break;
1523     }
1524 
1525     NOT_PRODUCT( parse_histogram()->set_initial_state(bc()); );
1526 
1527 #ifdef ASSERT
1528     int pre_bc_sp = sp();
1529     int inputs, depth;
1530     bool have_se = !stopped() && compute_stack_effects(inputs, depth);
1531     assert(!have_se || pre_bc_sp >= inputs, "have enough stack to execute this BC: pre_bc_sp=%d, inputs=%d", pre_bc_sp, inputs);
1532 #endif //ASSERT
1533 
1534     do_one_bytecode();
1535 
1536     assert(!have_se || stopped() || failing() || (sp() - pre_bc_sp) == depth,
1537            "incorrect depth prediction: sp=%d, pre_bc_sp=%d, depth=%d", sp(), pre_bc_sp, depth);
1538 
1539     do_exceptions();
1540 
1541     NOT_PRODUCT( parse_histogram()->record_change(); );
1542 
1543     if (log != NULL)
1544       log->clear_context();  // skip marker if nothing was printed
1545 
1546     // Fall into next bytecode.  Each bytecode normally has 1 sequential
1547     // successor which is typically made ready by visiting this bytecode.
1548     // If the successor has several predecessors, then it is a merge
1549     // point, starts a new basic block, and is handled like other basic blocks.
1550   }
1551 }
1552 
1553 
1554 //------------------------------merge------------------------------------------
1555 void Parse::set_parse_bci(int bci) {
1556   set_bci(bci);
1557   Node_Notes* nn = C->default_node_notes();
1558   if (nn == NULL)  return;
1559 
1560   // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
1561   if (!DebugInlinedCalls && depth() > 1) {
1562     return;
1563   }
1564 
1565   // Update the JVMS annotation, if present.
1566   JVMState* jvms = nn->jvms();
1567   if (jvms != NULL && jvms->bci() != bci) {
1568     // Update the JVMS.
1569     jvms = jvms->clone_shallow(C);
1570     jvms->set_bci(bci);
1571     nn->set_jvms(jvms);
1572   }
1573 }
1574 
1575 //------------------------------merge------------------------------------------
1576 // Merge the current mapping into the basic block starting at bci
1577 void Parse::merge(int target_bci) {
1578   Block* target = successor_for_bci(target_bci);
1579   if (target == NULL) { handle_missing_successor(target_bci); return; }
1580   assert(!target->is_ready(), "our arrival must be expected");
1581   int pnum = target->next_path_num();
1582   merge_common(target, pnum);
1583 }
1584 
1585 //-------------------------merge_new_path--------------------------------------
1586 // Merge the current mapping into the basic block, using a new path
1587 void Parse::merge_new_path(int target_bci) {
1588   Block* target = successor_for_bci(target_bci);
1589   if (target == NULL) { handle_missing_successor(target_bci); return; }
1590   assert(!target->is_ready(), "new path into frozen graph");
1591   int pnum = target->add_new_path();
1592   merge_common(target, pnum);
1593 }
1594 
1595 //-------------------------merge_exception-------------------------------------
1596 // Merge the current mapping into the basic block starting at bci
1597 // The ex_oop must be pushed on the stack, unlike throw_to_exit.
1598 void Parse::merge_exception(int target_bci) {
1599   assert(sp() == 1, "must have only the throw exception on the stack");
1600   Block* target = successor_for_bci(target_bci);
1601   if (target == NULL) { handle_missing_successor(target_bci); return; }
1602   assert(target->is_handler(), "exceptions are handled by special blocks");
1603   int pnum = target->add_new_path();
1604   merge_common(target, pnum);
1605 }
1606 
1607 //--------------------handle_missing_successor---------------------------------
1608 void Parse::handle_missing_successor(int target_bci) {
1609 #ifndef PRODUCT
1610   Block* b = block();
1611   int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
1612   tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
1613 #endif
1614   ShouldNotReachHere();
1615 }
1616 
1617 //--------------------------merge_common---------------------------------------
1618 void Parse::merge_common(Parse::Block* target, int pnum) {
1619   if (TraceOptoParse) {
1620     tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
1621   }
1622 
1623   // Zap extra stack slots to top
1624   assert(sp() == target->start_sp(), "");
1625   clean_stack(sp());
1626 
1627   if (!target->is_merged()) {   // No prior mapping at this bci
1628     if (TraceOptoParse) { tty->print(" with empty state");  }
1629 
1630     // If this path is dead, do not bother capturing it as a merge.
1631     // It is "as if" we had 1 fewer predecessors from the beginning.
1632     if (stopped()) {
1633       if (TraceOptoParse)  tty->print_cr(", but path is dead and doesn't count");
1634       return;
1635     }
1636 
1637     // Make a region if we know there are multiple or unpredictable inputs.
1638     // (Also, if this is a plain fall-through, we might see another region,
1639     // which must not be allowed into this block's map.)
1640     if (pnum > PhiNode::Input         // Known multiple inputs.
1641         || target->is_handler()       // These have unpredictable inputs.
1642         || target->is_loop_head()     // Known multiple inputs
1643         || control()->is_Region()) {  // We must hide this guy.
1644 
1645       int current_bci = bci();
1646       set_parse_bci(target->start()); // Set target bci
1647       if (target->is_SEL_head()) {
1648         DEBUG_ONLY( target->mark_merged_backedge(block()); )
1649         if (target->start() == 0) {
1650           // Add loop predicate for the special case when
1651           // there are backbranches to the method entry.
1652           add_predicate();
1653         }
1654       }
1655       // Add a Region to start the new basic block.  Phis will be added
1656       // later lazily.
1657       int edges = target->pred_count();
1658       if (edges < pnum)  edges = pnum;  // might be a new path!
1659       RegionNode *r = new RegionNode(edges+1);
1660       gvn().set_type(r, Type::CONTROL);
1661       record_for_igvn(r);
1662       // zap all inputs to NULL for debugging (done in Node(uint) constructor)
1663       // for (int j = 1; j < edges+1; j++) { r->init_req(j, NULL); }
1664       r->init_req(pnum, control());
1665       set_control(r);
1666       set_parse_bci(current_bci); // Restore bci
1667     }
1668 
1669     // Convert the existing Parser mapping into a mapping at this bci.
1670     store_state_to(target);
1671     assert(target->is_merged(), "do not come here twice");
1672 
1673   } else {                      // Prior mapping at this bci
1674     if (TraceOptoParse) {  tty->print(" with previous state"); }
1675 #ifdef ASSERT
1676     if (target->is_SEL_head()) {
1677       target->mark_merged_backedge(block());
1678     }
1679 #endif
1680     // We must not manufacture more phis if the target is already parsed.
1681     bool nophi = target->is_parsed();
1682 
1683     SafePointNode* newin = map();// Hang on to incoming mapping
1684     Block* save_block = block(); // Hang on to incoming block;
1685     load_state_from(target);    // Get prior mapping
1686 
1687     assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1688     assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1689     assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1690     assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1691 
1692     // Iterate over my current mapping and the old mapping.
1693     // Where different, insert Phi functions.
1694     // Use any existing Phi functions.
1695     assert(control()->is_Region(), "must be merging to a region");
1696     RegionNode* r = control()->as_Region();
1697 
1698     // Compute where to merge into
1699     // Merge incoming control path
1700     r->init_req(pnum, newin->control());
1701 
1702     if (pnum == 1) {            // Last merge for this Region?
1703       if (!block()->flow()->is_irreducible_entry()) {
1704         Node* result = _gvn.transform_no_reclaim(r);
1705         if (r != result && TraceOptoParse) {
1706           tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1707         }
1708       }
1709       record_for_igvn(r);
1710     }
1711 
1712     // Update all the non-control inputs to map:
1713     assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1714     bool check_elide_phi = target->is_SEL_backedge(save_block);
1715     for (uint j = 1; j < newin->req(); j++) {
1716       Node* m = map()->in(j);   // Current state of target.
1717       Node* n = newin->in(j);   // Incoming change to target state.
1718       PhiNode* phi;
1719       if (m->is_Phi() && m->as_Phi()->region() == r)
1720         phi = m->as_Phi();
1721       else
1722         phi = NULL;
1723       if (m != n) {             // Different; must merge
1724         switch (j) {
1725         // Frame pointer and Return Address never changes
1726         case TypeFunc::FramePtr:// Drop m, use the original value
1727         case TypeFunc::ReturnAdr:
1728           break;
1729         case TypeFunc::Memory:  // Merge inputs to the MergeMem node
1730           assert(phi == NULL, "the merge contains phis, not vice versa");
1731           merge_memory_edges(n->as_MergeMem(), pnum, nophi);
1732           continue;
1733         default:                // All normal stuff
1734           if (phi == NULL) {
1735             const JVMState* jvms = map()->jvms();
1736             if (EliminateNestedLocks &&
1737                 jvms->is_mon(j) && jvms->is_monitor_box(j)) {
1738               // BoxLock nodes are not commoning.
1739               // Use old BoxLock node as merged box.
1740               assert(newin->jvms()->is_monitor_box(j), "sanity");
1741               // This assert also tests that nodes are BoxLock.
1742               assert(BoxLockNode::same_slot(n, m), "sanity");
1743               C->gvn_replace_by(n, m);
1744             } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
1745               phi = ensure_phi(j, nophi);
1746             }
1747           }
1748           break;
1749         }
1750       }
1751       // At this point, n might be top if:
1752       //  - there is no phi (because TypeFlow detected a conflict), or
1753       //  - the corresponding control edges is top (a dead incoming path)
1754       // It is a bug if we create a phi which sees a garbage value on a live path.
1755 
1756       if (phi != NULL) {
1757         assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
1758         assert(phi->region() == r, "");
1759         phi->set_req(pnum, n);  // Then add 'n' to the merge
1760         if (pnum == PhiNode::Input) {
1761           // Last merge for this Phi.
1762           // So far, Phis have had a reasonable type from ciTypeFlow.
1763           // Now _gvn will join that with the meet of current inputs.
1764           // BOTTOM is never permissible here, 'cause pessimistically
1765           // Phis of pointers cannot lose the basic pointer type.
1766           debug_only(const Type* bt1 = phi->bottom_type());
1767           assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
1768           map()->set_req(j, _gvn.transform_no_reclaim(phi));
1769           debug_only(const Type* bt2 = phi->bottom_type());
1770           assert(bt2->higher_equal_speculative(bt1), "must be consistent with type-flow");
1771           record_for_igvn(phi);
1772         }
1773       }
1774     } // End of for all values to be merged
1775 
1776     if (pnum == PhiNode::Input &&
1777         !r->in(0)) {         // The occasional useless Region
1778       assert(control() == r, "");
1779       set_control(r->nonnull_req());
1780     }
1781 
1782     map()->merge_replaced_nodes_with(newin);
1783 
1784     // newin has been subsumed into the lazy merge, and is now dead.
1785     set_block(save_block);
1786 
1787     stop();                     // done with this guy, for now
1788   }
1789 
1790   if (TraceOptoParse) {
1791     tty->print_cr(" on path %d", pnum);
1792   }
1793 
1794   // Done with this parser state.
1795   assert(stopped(), "");
1796 }
1797 
1798 
1799 //--------------------------merge_memory_edges---------------------------------
1800 void Parse::merge_memory_edges(MergeMemNode* n, int pnum, bool nophi) {
1801   // (nophi means we must not create phis, because we already parsed here)
1802   assert(n != NULL, "");
1803   // Merge the inputs to the MergeMems
1804   MergeMemNode* m = merged_memory();
1805 
1806   assert(control()->is_Region(), "must be merging to a region");
1807   RegionNode* r = control()->as_Region();
1808 
1809   PhiNode* base = NULL;
1810   MergeMemNode* remerge = NULL;
1811   for (MergeMemStream mms(m, n); mms.next_non_empty2(); ) {
1812     Node *p = mms.force_memory();
1813     Node *q = mms.memory2();
1814     if (mms.is_empty() && nophi) {
1815       // Trouble:  No new splits allowed after a loop body is parsed.
1816       // Instead, wire the new split into a MergeMem on the backedge.
1817       // The optimizer will sort it out, slicing the phi.
1818       if (remerge == NULL) {
1819         assert(base != NULL, "");
1820         assert(base->in(0) != NULL, "should not be xformed away");
1821         remerge = MergeMemNode::make(base->in(pnum));
1822         gvn().set_type(remerge, Type::MEMORY);
1823         base->set_req(pnum, remerge);
1824       }
1825       remerge->set_memory_at(mms.alias_idx(), q);
1826       continue;
1827     }
1828     assert(!q->is_MergeMem(), "");
1829     PhiNode* phi;
1830     if (p != q) {
1831       phi = ensure_memory_phi(mms.alias_idx(), nophi);
1832     } else {
1833       if (p->is_Phi() && p->as_Phi()->region() == r)
1834         phi = p->as_Phi();
1835       else
1836         phi = NULL;
1837     }
1838     // Insert q into local phi
1839     if (phi != NULL) {
1840       assert(phi->region() == r, "");
1841       p = phi;
1842       phi->set_req(pnum, q);
1843       if (mms.at_base_memory()) {
1844         base = phi;  // delay transforming it
1845       } else if (pnum == 1) {
1846         record_for_igvn(phi);
1847         p = _gvn.transform_no_reclaim(phi);
1848       }
1849       mms.set_memory(p);// store back through the iterator
1850     }
1851   }
1852   // Transform base last, in case we must fiddle with remerging.
1853   if (base != NULL && pnum == 1) {
1854     record_for_igvn(base);
1855     m->set_base_memory( _gvn.transform_no_reclaim(base) );
1856   }
1857 }
1858 
1859 
1860 //------------------------ensure_phis_everywhere-------------------------------
1861 void Parse::ensure_phis_everywhere() {
1862   ensure_phi(TypeFunc::I_O);
1863 
1864   // Ensure a phi on all currently known memories.
1865   for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
1866     ensure_memory_phi(mms.alias_idx());
1867     debug_only(mms.set_memory());  // keep the iterator happy
1868   }
1869 
1870   // Note:  This is our only chance to create phis for memory slices.
1871   // If we miss a slice that crops up later, it will have to be
1872   // merged into the base-memory phi that we are building here.
1873   // Later, the optimizer will comb out the knot, and build separate
1874   // phi-loops for each memory slice that matters.
1875 
1876   // Monitors must nest nicely and not get confused amongst themselves.
1877   // Phi-ify everything up to the monitors, though.
1878   uint monoff = map()->jvms()->monoff();
1879   uint nof_monitors = map()->jvms()->nof_monitors();
1880 
1881   assert(TypeFunc::Parms == map()->jvms()->locoff(), "parser map should contain only youngest jvms");
1882   bool check_elide_phi = block()->is_SEL_head();
1883   for (uint i = TypeFunc::Parms; i < monoff; i++) {
1884     if (!check_elide_phi || !block()->can_elide_SEL_phi(i)) {
1885       ensure_phi(i);
1886     }
1887   }
1888 
1889   // Even monitors need Phis, though they are well-structured.
1890   // This is true for OSR methods, and also for the rare cases where
1891   // a monitor object is the subject of a replace_in_map operation.
1892   // See bugs 4426707 and 5043395.
1893   for (uint m = 0; m < nof_monitors; m++) {
1894     ensure_phi(map()->jvms()->monitor_obj_offset(m));
1895   }
1896 }
1897 
1898 
1899 //-----------------------------add_new_path------------------------------------
1900 // Add a previously unaccounted predecessor to this block.
1901 int Parse::Block::add_new_path() {
1902   // If there is no map, return the lowest unused path number.
1903   if (!is_merged())  return pred_count()+1;  // there will be a map shortly
1904 
1905   SafePointNode* map = start_map();
1906   if (!map->control()->is_Region())
1907     return pred_count()+1;  // there may be a region some day
1908   RegionNode* r = map->control()->as_Region();
1909 
1910   // Add new path to the region.
1911   uint pnum = r->req();
1912   r->add_req(NULL);
1913 
1914   for (uint i = 1; i < map->req(); i++) {
1915     Node* n = map->in(i);
1916     if (i == TypeFunc::Memory) {
1917       // Ensure a phi on all currently known memories.
1918       for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
1919         Node* phi = mms.memory();
1920         if (phi->is_Phi() && phi->as_Phi()->region() == r) {
1921           assert(phi->req() == pnum, "must be same size as region");
1922           phi->add_req(NULL);
1923         }
1924       }
1925     } else {
1926       if (n->is_Phi() && n->as_Phi()->region() == r) {
1927         assert(n->req() == pnum, "must be same size as region");
1928         n->add_req(NULL);
1929       }
1930     }
1931   }
1932 
1933   return pnum;
1934 }
1935 
1936 //------------------------------ensure_phi-------------------------------------
1937 // Turn the idx'th entry of the current map into a Phi
1938 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
1939   SafePointNode* map = this->map();
1940   Node* region = map->control();
1941   assert(region->is_Region(), "");
1942 
1943   Node* o = map->in(idx);
1944   assert(o != NULL, "");
1945 
1946   if (o == top())  return NULL; // TOP always merges into TOP
1947 
1948   if (o->is_Phi() && o->as_Phi()->region() == region) {
1949     return o->as_Phi();
1950   }
1951 
1952   // Now use a Phi here for merging
1953   assert(!nocreate, "Cannot build a phi for a block already parsed.");
1954   const JVMState* jvms = map->jvms();
1955   const Type* t = NULL;
1956   if (jvms->is_loc(idx)) {
1957     t = block()->local_type_at(idx - jvms->locoff());
1958   } else if (jvms->is_stk(idx)) {
1959     t = block()->stack_type_at(idx - jvms->stkoff());
1960   } else if (jvms->is_mon(idx)) {
1961     assert(!jvms->is_monitor_box(idx), "no phis for boxes");
1962     t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
1963   } else if ((uint)idx < TypeFunc::Parms) {
1964     t = o->bottom_type();  // Type::RETURN_ADDRESS or such-like.
1965   } else {
1966     assert(false, "no type information for this phi");
1967   }
1968 
1969   // If the type falls to bottom, then this must be a local that
1970   // is mixing ints and oops or some such.  Forcing it to top
1971   // makes it go dead.
1972   if (t == Type::BOTTOM) {
1973     map->set_req(idx, top());
1974     return NULL;
1975   }
1976 
1977   // Do not create phis for top either.
1978   // A top on a non-null control flow must be an unused even after the.phi.
1979   if (t == Type::TOP || t == Type::HALF) {
1980     map->set_req(idx, top());
1981     return NULL;
1982   }
1983 
1984   PhiNode* phi = PhiNode::make(region, o, t);
1985   gvn().set_type(phi, t);
1986   if (C->do_escape_analysis()) record_for_igvn(phi);
1987   map->set_req(idx, phi);
1988   return phi;
1989 }
1990 
1991 //--------------------------ensure_memory_phi----------------------------------
1992 // Turn the idx'th slice of the current memory into a Phi
1993 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
1994   MergeMemNode* mem = merged_memory();
1995   Node* region = control();
1996   assert(region->is_Region(), "");
1997 
1998   Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
1999   assert(o != NULL && o != top(), "");
2000 
2001   PhiNode* phi;
2002   if (o->is_Phi() && o->as_Phi()->region() == region) {
2003     phi = o->as_Phi();
2004     if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
2005       // clone the shared base memory phi to make a new memory split
2006       assert(!nocreate, "Cannot build a phi for a block already parsed.");
2007       const Type* t = phi->bottom_type();
2008       const TypePtr* adr_type = C->get_adr_type(idx);
2009       phi = phi->slice_memory(adr_type);
2010       gvn().set_type(phi, t);
2011     }
2012     return phi;
2013   }
2014 
2015   // Now use a Phi here for merging
2016   assert(!nocreate, "Cannot build a phi for a block already parsed.");
2017   const Type* t = o->bottom_type();
2018   const TypePtr* adr_type = C->get_adr_type(idx);
2019   phi = PhiNode::make(region, o, t, adr_type);
2020   gvn().set_type(phi, t);
2021   if (idx == Compile::AliasIdxBot)
2022     mem->set_base_memory(phi);
2023   else
2024     mem->set_memory_at(idx, phi);
2025   return phi;
2026 }
2027 
2028 //------------------------------call_register_finalizer-----------------------
2029 // Check the klass of the receiver and call register_finalizer if the
2030 // class need finalization.
2031 void Parse::call_register_finalizer() {
2032   Node* receiver = local(0);
2033   assert(receiver != NULL && receiver->bottom_type()->isa_instptr() != NULL,
2034          "must have non-null instance type");
2035 
2036   const TypeInstPtr *tinst = receiver->bottom_type()->isa_instptr();
2037   if (tinst != NULL && tinst->klass()->is_loaded() && !tinst->klass_is_exact()) {
2038     // The type isn't known exactly so see if CHA tells us anything.
2039     ciInstanceKlass* ik = tinst->klass()->as_instance_klass();
2040     if (!Dependencies::has_finalizable_subclass(ik)) {
2041       // No finalizable subclasses so skip the dynamic check.
2042       C->dependencies()->assert_has_no_finalizable_subclasses(ik);
2043       return;
2044     }
2045   }
2046 
2047   // Insert a dynamic test for whether the instance needs
2048   // finalization.  In general this will fold up since the concrete
2049   // class is often visible so the access flags are constant.
2050   Node* klass_addr = basic_plus_adr( receiver, receiver, oopDesc::klass_offset_in_bytes() );
2051   Node* klass = _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), klass_addr, TypeInstPtr::KLASS));
2052 
2053   Node* access_flags_addr = basic_plus_adr(klass, klass, in_bytes(Klass::access_flags_offset()));
2054   Node* access_flags = make_load(NULL, access_flags_addr, TypeInt::INT, T_INT, MemNode::unordered);
2055 
2056   Node* mask  = _gvn.transform(new AndINode(access_flags, intcon(JVM_ACC_HAS_FINALIZER)));
2057   Node* check = _gvn.transform(new CmpINode(mask, intcon(0)));
2058   Node* test  = _gvn.transform(new BoolNode(check, BoolTest::ne));
2059 
2060   IfNode* iff = create_and_map_if(control(), test, PROB_MAX, COUNT_UNKNOWN);
2061 
2062   RegionNode* result_rgn = new RegionNode(3);
2063   record_for_igvn(result_rgn);
2064 
2065   Node *skip_register = _gvn.transform(new IfFalseNode(iff));
2066   result_rgn->init_req(1, skip_register);
2067 
2068   Node *needs_register = _gvn.transform(new IfTrueNode(iff));
2069   set_control(needs_register);
2070   if (stopped()) {
2071     // There is no slow path.
2072     result_rgn->init_req(2, top());
2073   } else {
2074     Node *call = make_runtime_call(RC_NO_LEAF,
2075                                    OptoRuntime::register_finalizer_Type(),
2076                                    OptoRuntime::register_finalizer_Java(),
2077                                    NULL, TypePtr::BOTTOM,
2078                                    receiver);
2079     make_slow_call_ex(call, env()->Throwable_klass(), true);
2080 
2081     Node* fast_io  = call->in(TypeFunc::I_O);
2082     Node* fast_mem = call->in(TypeFunc::Memory);
2083     // These two phis are pre-filled with copies of of the fast IO and Memory
2084     Node* io_phi   = PhiNode::make(result_rgn, fast_io,  Type::ABIO);
2085     Node* mem_phi  = PhiNode::make(result_rgn, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
2086 
2087     result_rgn->init_req(2, control());
2088     io_phi    ->init_req(2, i_o());
2089     mem_phi   ->init_req(2, reset_memory());
2090 
2091     set_all_memory( _gvn.transform(mem_phi) );
2092     set_i_o(        _gvn.transform(io_phi) );
2093   }
2094 
2095   set_control( _gvn.transform(result_rgn) );
2096 }
2097 
2098 // Add check to deoptimize if RTM state is not ProfileRTM
2099 void Parse::rtm_deopt() {
2100 #if INCLUDE_RTM_OPT
2101   if (C->profile_rtm()) {
2102     assert(C->method() != NULL, "only for normal compilations");
2103     assert(!C->method()->method_data()->is_empty(), "MDO is needed to record RTM state");
2104     assert(depth() == 1, "generate check only for main compiled method");
2105 
2106     // Set starting bci for uncommon trap.
2107     set_parse_bci(is_osr_parse() ? osr_bci() : 0);
2108 
2109     // Load the rtm_state from the MethodData.
2110     const TypePtr* adr_type = TypeMetadataPtr::make(C->method()->method_data());
2111     Node* mdo = makecon(adr_type);
2112     int offset = MethodData::rtm_state_offset_in_bytes();
2113     Node* adr_node = basic_plus_adr(mdo, mdo, offset);
2114     Node* rtm_state = make_load(control(), adr_node, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
2115 
2116     // Separate Load from Cmp by Opaque.
2117     // In expand_macro_nodes() it will be replaced either
2118     // with this load when there are locks in the code
2119     // or with ProfileRTM (cmp->in(2)) otherwise so that
2120     // the check will fold.
2121     Node* profile_state = makecon(TypeInt::make(ProfileRTM));
2122     Node* opq   = _gvn.transform( new Opaque3Node(C, rtm_state, Opaque3Node::RTM_OPT) );
2123     Node* chk   = _gvn.transform( new CmpINode(opq, profile_state) );
2124     Node* tst   = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
2125     // Branch to failure if state was changed
2126     { BuildCutout unless(this, tst, PROB_ALWAYS);
2127       uncommon_trap(Deoptimization::Reason_rtm_state_change,
2128                     Deoptimization::Action_make_not_entrant);
2129     }
2130   }
2131 #endif
2132 }
2133 
2134 void Parse::decrement_age() {
2135   MethodCounters* mc = method()->ensure_method_counters();
2136   if (mc == NULL) {
2137     C->record_failure("Must have MCs");
2138     return;
2139   }
2140   assert(!is_osr_parse(), "Not doing this for OSRs");
2141 
2142   // Set starting bci for uncommon trap.
2143   set_parse_bci(0);
2144 
2145   const TypePtr* adr_type = TypeRawPtr::make((address)mc);
2146   Node* mc_adr = makecon(adr_type);
2147   Node* cnt_adr = basic_plus_adr(mc_adr, mc_adr, in_bytes(MethodCounters::nmethod_age_offset()));
2148   Node* cnt = make_load(control(), cnt_adr, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
2149   Node* decr = _gvn.transform(new SubINode(cnt, makecon(TypeInt::ONE)));
2150   store_to_memory(control(), cnt_adr, decr, T_INT, adr_type, MemNode::unordered);
2151   Node *chk   = _gvn.transform(new CmpINode(decr, makecon(TypeInt::ZERO)));
2152   Node* tst   = _gvn.transform(new BoolNode(chk, BoolTest::gt));
2153   { BuildCutout unless(this, tst, PROB_ALWAYS);
2154     uncommon_trap(Deoptimization::Reason_tenured,
2155                   Deoptimization::Action_make_not_entrant);
2156   }
2157 }
2158 
2159 //------------------------------return_current---------------------------------
2160 // Append current _map to _exit_return
2161 void Parse::return_current(Node* value) {
2162   if (RegisterFinalizersAtInit &&
2163       method()->intrinsic_id() == vmIntrinsics::_Object_init) {
2164     call_register_finalizer();
2165   }
2166 
2167   // Do not set_parse_bci, so that return goo is credited to the return insn.
2168   set_bci(InvocationEntryBci);
2169   if (method()->is_synchronized() && GenerateSynchronizationCode) {
2170     shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
2171   }
2172   if (C->env()->dtrace_method_probes()) {
2173     make_dtrace_method_exit(method());
2174   }
2175   SafePointNode* exit_return = _exits.map();
2176   exit_return->in( TypeFunc::Control  )->add_req( control() );
2177   exit_return->in( TypeFunc::I_O      )->add_req( i_o    () );
2178   Node *mem = exit_return->in( TypeFunc::Memory   );
2179   for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
2180     if (mms.is_empty()) {
2181       // get a copy of the base memory, and patch just this one input
2182       const TypePtr* adr_type = mms.adr_type(C);
2183       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
2184       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
2185       gvn().set_type_bottom(phi);
2186       phi->del_req(phi->req()-1);  // prepare to re-patch
2187       mms.set_memory(phi);
2188     }
2189     mms.memory()->add_req(mms.memory2());
2190   }
2191 
2192   // frame pointer is always same, already captured
2193   if (value != NULL) {
2194     // If returning oops to an interface-return, there is a silent free
2195     // cast from oop to interface allowed by the Verifier.  Make it explicit
2196     // here.
2197     Node* phi = _exits.argument(0);
2198     const TypeInstPtr *tr = phi->bottom_type()->isa_instptr();
2199     if (tr && tr->klass()->is_loaded() &&
2200         tr->klass()->is_interface()) {
2201       const TypeInstPtr *tp = value->bottom_type()->isa_instptr();
2202       if (tp && tp->klass()->is_loaded() &&
2203           !tp->klass()->is_interface()) {
2204         // sharpen the type eagerly; this eases certain assert checking
2205         if (tp->higher_equal(TypeInstPtr::NOTNULL))
2206           tr = tr->join_speculative(TypeInstPtr::NOTNULL)->is_instptr();
2207         value = _gvn.transform(new CheckCastPPNode(0, value, tr));
2208       }
2209     } else {
2210       // Also handle returns of oop-arrays to an arrays-of-interface return
2211       const TypeInstPtr* phi_tip;
2212       const TypeInstPtr* val_tip;
2213       Type::get_arrays_base_elements(phi->bottom_type(), value->bottom_type(), &phi_tip, &val_tip);
2214       if (phi_tip != NULL && phi_tip->is_loaded() && phi_tip->klass()->is_interface() &&
2215           val_tip != NULL && val_tip->is_loaded() && !val_tip->klass()->is_interface()) {
2216         value = _gvn.transform(new CheckCastPPNode(0, value, phi->bottom_type()));
2217       }
2218     }
2219     phi->add_req(value);
2220   }
2221 
2222   if (_first_return) {
2223     _exits.map()->transfer_replaced_nodes_from(map(), _new_idx);
2224     _first_return = false;
2225   } else {
2226     _exits.map()->merge_replaced_nodes_with(map());
2227   }
2228 
2229   stop_and_kill_map();          // This CFG path dies here
2230 }
2231 
2232 
2233 //------------------------------add_safepoint----------------------------------
2234 void Parse::add_safepoint() {
2235   // See if we can avoid this safepoint.  No need for a SafePoint immediately
2236   // after a Call (except Leaf Call) or another SafePoint.
2237   Node *proj = control();
2238   bool add_poll_param = SafePointNode::needs_polling_address_input();
2239   uint parms = add_poll_param ? TypeFunc::Parms+1 : TypeFunc::Parms;
2240   if( proj->is_Proj() ) {
2241     Node *n0 = proj->in(0);
2242     if( n0->is_Catch() ) {
2243       n0 = n0->in(0)->in(0);
2244       assert( n0->is_Call(), "expect a call here" );
2245     }
2246     if( n0->is_Call() ) {
2247       if( n0->as_Call()->guaranteed_safepoint() )
2248         return;
2249     } else if( n0->is_SafePoint() && n0->req() >= parms ) {
2250       return;
2251     }
2252   }
2253 
2254   // Clear out dead values from the debug info.
2255   kill_dead_locals();
2256 
2257   // Clone the JVM State
2258   SafePointNode *sfpnt = new SafePointNode(parms, NULL);
2259 
2260   // Capture memory state BEFORE a SafePoint.  Since we can block at a
2261   // SafePoint we need our GC state to be safe; i.e. we need all our current
2262   // write barriers (card marks) to not float down after the SafePoint so we
2263   // must read raw memory.  Likewise we need all oop stores to match the card
2264   // marks.  If deopt can happen, we need ALL stores (we need the correct JVM
2265   // state on a deopt).
2266 
2267   // We do not need to WRITE the memory state after a SafePoint.  The control
2268   // edge will keep card-marks and oop-stores from floating up from below a
2269   // SafePoint and our true dependency added here will keep them from floating
2270   // down below a SafePoint.
2271 
2272   // Clone the current memory state
2273   Node* mem = MergeMemNode::make(map()->memory());
2274 
2275   mem = _gvn.transform(mem);
2276 
2277   // Pass control through the safepoint
2278   sfpnt->init_req(TypeFunc::Control  , control());
2279   // Fix edges normally used by a call
2280   sfpnt->init_req(TypeFunc::I_O      , top() );
2281   sfpnt->init_req(TypeFunc::Memory   , mem   );
2282   sfpnt->init_req(TypeFunc::ReturnAdr, top() );
2283   sfpnt->init_req(TypeFunc::FramePtr , top() );
2284 
2285   // Create a node for the polling address
2286   if( add_poll_param ) {
2287     Node *polladr = ConPNode::make((address)os::get_polling_page());
2288     sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
2289   }
2290 
2291   // Fix up the JVM State edges
2292   add_safepoint_edges(sfpnt);
2293   Node *transformed_sfpnt = _gvn.transform(sfpnt);
2294   set_control(transformed_sfpnt);
2295 
2296   // Provide an edge from root to safepoint.  This makes the safepoint
2297   // appear useful until the parse has completed.
2298   if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
2299     assert(C->root() != NULL, "Expect parse is still valid");
2300     C->root()->add_prec(transformed_sfpnt);
2301   }
2302 }
2303 
2304 #ifndef PRODUCT
2305 //------------------------show_parse_info--------------------------------------
2306 void Parse::show_parse_info() {
2307   InlineTree* ilt = NULL;
2308   if (C->ilt() != NULL) {
2309     JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
2310     ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
2311   }
2312   if (PrintCompilation && Verbose) {
2313     if (depth() == 1) {
2314       if( ilt->count_inlines() ) {
2315         tty->print("    __inlined %d (%d bytes)", ilt->count_inlines(),
2316                      ilt->count_inline_bcs());
2317         tty->cr();
2318       }
2319     } else {
2320       if (method()->is_synchronized())         tty->print("s");
2321       if (method()->has_exception_handlers())  tty->print("!");
2322       // Check this is not the final compiled version
2323       if (C->trap_can_recompile()) {
2324         tty->print("-");
2325       } else {
2326         tty->print(" ");
2327       }
2328       method()->print_short_name();
2329       if (is_osr_parse()) {
2330         tty->print(" @ %d", osr_bci());
2331       }
2332       tty->print(" (%d bytes)",method()->code_size());
2333       if (ilt->count_inlines()) {
2334         tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2335                    ilt->count_inline_bcs());
2336       }
2337       tty->cr();
2338     }
2339   }
2340   if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
2341     // Print that we succeeded; suppress this message on the first osr parse.
2342 
2343     if (method()->is_synchronized())         tty->print("s");
2344     if (method()->has_exception_handlers())  tty->print("!");
2345     // Check this is not the final compiled version
2346     if (C->trap_can_recompile() && depth() == 1) {
2347       tty->print("-");
2348     } else {
2349       tty->print(" ");
2350     }
2351     if( depth() != 1 ) { tty->print("   "); }  // missing compile count
2352     for (int i = 1; i < depth(); ++i) { tty->print("  "); }
2353     method()->print_short_name();
2354     if (is_osr_parse()) {
2355       tty->print(" @ %d", osr_bci());
2356     }
2357     if (ilt->caller_bci() != -1) {
2358       tty->print(" @ %d", ilt->caller_bci());
2359     }
2360     tty->print(" (%d bytes)",method()->code_size());
2361     if (ilt->count_inlines()) {
2362       tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2363                  ilt->count_inline_bcs());
2364     }
2365     tty->cr();
2366   }
2367 }
2368 
2369 
2370 //------------------------------dump-------------------------------------------
2371 // Dump information associated with the bytecodes of current _method
2372 void Parse::dump() {
2373   if( method() != NULL ) {
2374     // Iterate over bytecodes
2375     ciBytecodeStream iter(method());
2376     for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
2377       dump_bci( iter.cur_bci() );
2378       tty->cr();
2379     }
2380   }
2381 }
2382 
2383 // Dump information associated with a byte code index, 'bci'
2384 void Parse::dump_bci(int bci) {
2385   // Output info on merge-points, cloning, and within _jsr..._ret
2386   // NYI
2387   tty->print(" bci:%d", bci);
2388 }
2389 
2390 #endif