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 BitMap 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_all_tiers(_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             (UseLoopPredicate || LoopLimitCheck)) {
 667           // Add predicate to single entry (not irreducible) loop head.
 668           assert(!block->has_merged_backedge(), "only entry paths should be merged for now");
 669           // Need correct bci for predicate.
 670           // It is fine to set it here since do_one_block() will set it anyway.
 671           set_parse_bci(block->start());
 672           add_predicate();
 673           // Add new region for back branches.
 674           int edges = block->pred_count() - block->preds_parsed() + 1; // +1 for original region
 675           RegionNode *r = new RegionNode(edges+1);
 676           _gvn.set_type(r, Type::CONTROL);
 677           record_for_igvn(r);
 678           r->init_req(edges, control());
 679           set_control(r);
 680           // Add new phis.
 681           ensure_phis_everywhere();
 682         }
 683 
 684         // Leave behind an undisturbed copy of the map, for future merges.
 685         set_map(clone_map());
 686       }
 687 
 688       if (control()->is_Region() && !block->is_loop_head() && !has_irreducible && !block->is_handler()) {
 689         // In the absence of irreducible loops, the Region and Phis
 690         // associated with a merge that doesn't involve a backedge can
 691         // be simplified now since the RPO parsing order guarantees
 692         // that any path which was supposed to reach here has already
 693         // been parsed or must be dead.
 694         Node* c = control();
 695         Node* result = _gvn.transform_no_reclaim(control());
 696         if (c != result && TraceOptoParse) {
 697           tty->print_cr("Block #%d replace %d with %d", block->rpo(), c->_idx, result->_idx);
 698         }
 699         if (result != top()) {
 700           record_for_igvn(result);
 701         }
 702       }
 703 
 704       // Parse the block.
 705       do_one_block();
 706 
 707       // Check for bailouts.
 708       if (failing())  return;
 709     }
 710 
 711     // with irreducible loops multiple passes might be necessary to parse everything
 712     if (!has_irreducible || !progress) {
 713       break;
 714     }
 715   }
 716 
 717 #ifndef PRODUCT
 718   blocks_seen += block_count();
 719 
 720   // Make sure there are no half-processed blocks remaining.
 721   // Every remaining unprocessed block is dead and may be ignored now.
 722   for (int rpo = 0; rpo < block_count(); rpo++) {
 723     Block* block = rpo_at(rpo);
 724     if (!block->is_parsed()) {
 725       if (TraceOptoParse) {
 726         tty->print_cr("Skipped dead block %d at bci:%d", rpo, block->start());
 727       }
 728       assert(!block->is_merged(), "no half-processed blocks");
 729     }
 730   }
 731 #endif
 732 }
 733 
 734 //-------------------------------build_exits----------------------------------
 735 // Build normal and exceptional exit merge points.
 736 void Parse::build_exits() {
 737   // make a clone of caller to prevent sharing of side-effects
 738   _exits.set_map(_exits.clone_map());
 739   _exits.clean_stack(_exits.sp());
 740   _exits.sync_jvms();
 741 
 742   RegionNode* region = new RegionNode(1);
 743   record_for_igvn(region);
 744   gvn().set_type_bottom(region);
 745   _exits.set_control(region);
 746 
 747   // Note:  iophi and memphi are not transformed until do_exits.
 748   Node* iophi  = new PhiNode(region, Type::ABIO);
 749   Node* memphi = new PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
 750   gvn().set_type_bottom(iophi);
 751   gvn().set_type_bottom(memphi);
 752   _exits.set_i_o(iophi);
 753   _exits.set_all_memory(memphi);
 754 
 755   // Add a return value to the exit state.  (Do not push it yet.)
 756   if (tf()->range()->cnt() > TypeFunc::Parms) {
 757     const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
 758     // Don't "bind" an unloaded return klass to the ret_phi. If the klass
 759     // becomes loaded during the subsequent parsing, the loaded and unloaded
 760     // types will not join when we transform and push in do_exits().
 761     const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
 762     if (ret_oop_type && !ret_oop_type->klass()->is_loaded()) {
 763       ret_type = TypeOopPtr::BOTTOM;
 764     }
 765     int         ret_size = type2size[ret_type->basic_type()];
 766     Node*       ret_phi  = new PhiNode(region, ret_type);
 767     gvn().set_type_bottom(ret_phi);
 768     _exits.ensure_stack(ret_size);
 769     assert((int)(tf()->range()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
 770     assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
 771     _exits.set_argument(0, ret_phi);  // here is where the parser finds it
 772     // Note:  ret_phi is not yet pushed, until do_exits.
 773   }
 774 }
 775 
 776 
 777 //----------------------------build_start_state-------------------------------
 778 // Construct a state which contains only the incoming arguments from an
 779 // unknown caller.  The method & bci will be NULL & InvocationEntryBci.
 780 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
 781   int        arg_size = tf->domain()->cnt();
 782   int        max_size = MAX2(arg_size, (int)tf->range()->cnt());
 783   JVMState*  jvms     = new (this) JVMState(max_size - TypeFunc::Parms);
 784   SafePointNode* map  = new SafePointNode(max_size, NULL);
 785   record_for_igvn(map);
 786   assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
 787   Node_Notes* old_nn = default_node_notes();
 788   if (old_nn != NULL && has_method()) {
 789     Node_Notes* entry_nn = old_nn->clone(this);
 790     JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
 791     entry_jvms->set_offsets(0);
 792     entry_jvms->set_bci(entry_bci());
 793     entry_nn->set_jvms(entry_jvms);
 794     set_default_node_notes(entry_nn);
 795   }
 796   uint i;
 797   for (i = 0; i < (uint)arg_size; i++) {
 798     Node* parm = initial_gvn()->transform(new ParmNode(start, i));
 799     map->init_req(i, parm);
 800     // Record all these guys for later GVN.
 801     record_for_igvn(parm);
 802   }
 803   for (; i < map->req(); i++) {
 804     map->init_req(i, top());
 805   }
 806   assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
 807   set_default_node_notes(old_nn);
 808   map->set_jvms(jvms);
 809   jvms->set_map(map);
 810   return jvms;
 811 }
 812 
 813 //-----------------------------make_node_notes---------------------------------
 814 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
 815   if (caller_nn == NULL)  return NULL;
 816   Node_Notes* nn = caller_nn->clone(C);
 817   JVMState* caller_jvms = nn->jvms();
 818   JVMState* jvms = new (C) JVMState(method(), caller_jvms);
 819   jvms->set_offsets(0);
 820   jvms->set_bci(_entry_bci);
 821   nn->set_jvms(jvms);
 822   return nn;
 823 }
 824 
 825 
 826 //--------------------------return_values--------------------------------------
 827 void Compile::return_values(JVMState* jvms) {
 828   GraphKit kit(jvms);
 829   Node* ret = new ReturnNode(TypeFunc::Parms,
 830                              kit.control(),
 831                              kit.i_o(),
 832                              kit.reset_memory(),
 833                              kit.frameptr(),
 834                              kit.returnadr());
 835   // Add zero or 1 return values
 836   int ret_size = tf()->range()->cnt() - TypeFunc::Parms;
 837   if (ret_size > 0) {
 838     kit.inc_sp(-ret_size);  // pop the return value(s)
 839     kit.sync_jvms();
 840     ret->add_req(kit.argument(0));
 841     // Note:  The second dummy edge is not needed by a ReturnNode.
 842   }
 843   // bind it to root
 844   root()->add_req(ret);
 845   record_for_igvn(ret);
 846   initial_gvn()->transform_no_reclaim(ret);
 847 }
 848 
 849 //------------------------rethrow_exceptions-----------------------------------
 850 // Bind all exception states in the list into a single RethrowNode.
 851 void Compile::rethrow_exceptions(JVMState* jvms) {
 852   GraphKit kit(jvms);
 853   if (!kit.has_exceptions())  return;  // nothing to generate
 854   // Load my combined exception state into the kit, with all phis transformed:
 855   SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
 856   Node* ex_oop = kit.use_exception_state(ex_map);
 857   RethrowNode* exit = new RethrowNode(kit.control(),
 858                                       kit.i_o(), kit.reset_memory(),
 859                                       kit.frameptr(), kit.returnadr(),
 860                                       // like a return but with exception input
 861                                       ex_oop);
 862   // bind to root
 863   root()->add_req(exit);
 864   record_for_igvn(exit);
 865   initial_gvn()->transform_no_reclaim(exit);
 866 }
 867 
 868 //---------------------------do_exceptions-------------------------------------
 869 // Process exceptions arising from the current bytecode.
 870 // Send caught exceptions to the proper handler within this method.
 871 // Unhandled exceptions feed into _exit.
 872 void Parse::do_exceptions() {
 873   if (!has_exceptions())  return;
 874 
 875   if (failing()) {
 876     // Pop them all off and throw them away.
 877     while (pop_exception_state() != NULL) ;
 878     return;
 879   }
 880 
 881   PreserveJVMState pjvms(this, false);
 882 
 883   SafePointNode* ex_map;
 884   while ((ex_map = pop_exception_state()) != NULL) {
 885     if (!method()->has_exception_handlers()) {
 886       // Common case:  Transfer control outward.
 887       // Doing it this early allows the exceptions to common up
 888       // even between adjacent method calls.
 889       throw_to_exit(ex_map);
 890     } else {
 891       // Have to look at the exception first.
 892       assert(stopped(), "catch_inline_exceptions trashes the map");
 893       catch_inline_exceptions(ex_map);
 894       stop_and_kill_map();      // we used up this exception state; kill it
 895     }
 896   }
 897 
 898   // We now return to our regularly scheduled program:
 899 }
 900 
 901 //---------------------------throw_to_exit-------------------------------------
 902 // Merge the given map into an exception exit from this method.
 903 // The exception exit will handle any unlocking of receiver.
 904 // The ex_oop must be saved within the ex_map, unlike merge_exception.
 905 void Parse::throw_to_exit(SafePointNode* ex_map) {
 906   // Pop the JVMS to (a copy of) the caller.
 907   GraphKit caller;
 908   caller.set_map_clone(_caller->map());
 909   caller.set_bci(_caller->bci());
 910   caller.set_sp(_caller->sp());
 911   // Copy out the standard machine state:
 912   for (uint i = 0; i < TypeFunc::Parms; i++) {
 913     caller.map()->set_req(i, ex_map->in(i));
 914   }
 915   if (ex_map->has_replaced_nodes()) {
 916     _replaced_nodes_for_exceptions = true;
 917   }
 918   caller.map()->transfer_replaced_nodes_from(ex_map, _new_idx);
 919   // ...and the exception:
 920   Node*          ex_oop        = saved_ex_oop(ex_map);
 921   SafePointNode* caller_ex_map = caller.make_exception_state(ex_oop);
 922   // Finally, collect the new exception state in my exits:
 923   _exits.add_exception_state(caller_ex_map);
 924 }
 925 
 926 //------------------------------do_exits---------------------------------------
 927 void Parse::do_exits() {
 928   set_parse_bci(InvocationEntryBci);
 929 
 930   // Now peephole on the return bits
 931   Node* region = _exits.control();
 932   _exits.set_control(gvn().transform(region));
 933 
 934   Node* iophi = _exits.i_o();
 935   _exits.set_i_o(gvn().transform(iophi));
 936 
 937   // Figure out if we need to emit the trailing barrier. The barrier is only
 938   // needed in the constructors, and only in three cases:
 939   //
 940   // 1. The constructor wrote a final. The effects of all initializations
 941   //    must be committed to memory before any code after the constructor
 942   //    publishes the reference to the newly constructed object. Rather
 943   //    than wait for the publication, we simply block the writes here.
 944   //    Rather than put a barrier on only those writes which are required
 945   //    to complete, we force all writes to complete.
 946   //
 947   // 2. On PPC64, also add MemBarRelease for constructors which write
 948   //    volatile fields. As support_IRIW_for_not_multiple_copy_atomic_cpu
 949   //    is set on PPC64, no sync instruction is issued after volatile
 950   //    stores. We want to guarantee the same behavior as on platforms
 951   //    with total store order, although this is not required by the Java
 952   //    memory model. So as with finals, we add a barrier here.
 953   //
 954   // 3. Experimental VM option is used to force the barrier if any field
 955   //    was written out in the constructor.
 956   //
 957   // "All bets are off" unless the first publication occurs after a
 958   // normal return from the constructor.  We do not attempt to detect
 959   // such unusual early publications.  But no barrier is needed on
 960   // exceptional returns, since they cannot publish normally.
 961   //
 962   if (method()->is_initializer() &&
 963         (wrote_final() ||
 964            PPC64_ONLY(wrote_volatile() ||)
 965            (AlwaysSafeConstructors && wrote_fields()))) {
 966     _exits.insert_mem_bar(Op_MemBarRelease, alloc_with_final());
 967 
 968     // If Memory barrier is created for final fields write
 969     // and allocation node does not escape the initialize method,
 970     // then barrier introduced by allocation node can be removed.
 971     if (DoEscapeAnalysis && alloc_with_final()) {
 972       AllocateNode *alloc = AllocateNode::Ideal_allocation(alloc_with_final(), &_gvn);
 973       alloc->compute_MemBar_redundancy(method());
 974     }
 975     if (PrintOpto && (Verbose || WizardMode)) {
 976       method()->print_name();
 977       tty->print_cr(" writes finals and needs a memory barrier");
 978     }
 979   }
 980 
 981   // Any method can write a @Stable field; insert memory barriers
 982   // after those also. Can't bind predecessor allocation node (if any)
 983   // with barrier because allocation doesn't always dominate
 984   // MemBarRelease.
 985   if (wrote_stable()) {
 986     _exits.insert_mem_bar(Op_MemBarRelease);
 987     if (PrintOpto && (Verbose || WizardMode)) {
 988       method()->print_name();
 989       tty->print_cr(" writes @Stable and needs a memory barrier");
 990     }
 991   }
 992 
 993   for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
 994     // transform each slice of the original memphi:
 995     mms.set_memory(_gvn.transform(mms.memory()));
 996   }
 997 
 998   if (tf()->range()->cnt() > TypeFunc::Parms) {
 999     const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
1000     Node*       ret_phi  = _gvn.transform( _exits.argument(0) );
1001     if (!_exits.control()->is_top() && _gvn.type(ret_phi)->empty()) {
1002       // In case of concurrent class loading, the type we set for the
1003       // ret_phi in build_exits() may have been too optimistic and the
1004       // ret_phi may be top now.
1005       // Otherwise, we've encountered an error and have to mark the method as
1006       // not compilable. Just using an assertion instead would be dangerous
1007       // as this could lead to an infinite compile loop in non-debug builds.
1008       {
1009         MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
1010         if (C->env()->system_dictionary_modification_counter_changed()) {
1011           C->record_failure(C2Compiler::retry_class_loading_during_parsing());
1012         } else {
1013           C->record_method_not_compilable("Can't determine return type.");
1014         }
1015       }
1016       return;
1017     }
1018     _exits.push_node(ret_type->basic_type(), ret_phi);
1019   }
1020 
1021   // Note:  Logic for creating and optimizing the ReturnNode is in Compile.
1022 
1023   // Unlock along the exceptional paths.
1024   // This is done late so that we can common up equivalent exceptions
1025   // (e.g., null checks) arising from multiple points within this method.
1026   // See GraphKit::add_exception_state, which performs the commoning.
1027   bool do_synch = method()->is_synchronized() && GenerateSynchronizationCode;
1028 
1029   // record exit from a method if compiled while Dtrace is turned on.
1030   if (do_synch || C->env()->dtrace_method_probes() || _replaced_nodes_for_exceptions) {
1031     // First move the exception list out of _exits:
1032     GraphKit kit(_exits.transfer_exceptions_into_jvms());
1033     SafePointNode* normal_map = kit.map();  // keep this guy safe
1034     // Now re-collect the exceptions into _exits:
1035     SafePointNode* ex_map;
1036     while ((ex_map = kit.pop_exception_state()) != NULL) {
1037       Node* ex_oop = kit.use_exception_state(ex_map);
1038       // Force the exiting JVM state to have this method at InvocationEntryBci.
1039       // The exiting JVM state is otherwise a copy of the calling JVMS.
1040       JVMState* caller = kit.jvms();
1041       JVMState* ex_jvms = caller->clone_shallow(C);
1042       ex_jvms->set_map(kit.clone_map());
1043       ex_jvms->map()->set_jvms(ex_jvms);
1044       ex_jvms->set_bci(   InvocationEntryBci);
1045       kit.set_jvms(ex_jvms);
1046       if (do_synch) {
1047         // Add on the synchronized-method box/object combo
1048         kit.map()->push_monitor(_synch_lock);
1049         // Unlock!
1050         kit.shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
1051       }
1052       if (C->env()->dtrace_method_probes()) {
1053         kit.make_dtrace_method_exit(method());
1054       }
1055       if (_replaced_nodes_for_exceptions) {
1056         kit.map()->apply_replaced_nodes();
1057       }
1058       // Done with exception-path processing.
1059       ex_map = kit.make_exception_state(ex_oop);
1060       assert(ex_jvms->same_calls_as(ex_map->jvms()), "sanity");
1061       // Pop the last vestige of this method:
1062       ex_map->set_jvms(caller->clone_shallow(C));
1063       ex_map->jvms()->set_map(ex_map);
1064       _exits.push_exception_state(ex_map);
1065     }
1066     assert(_exits.map() == normal_map, "keep the same return state");
1067   }
1068 
1069   {
1070     // Capture very early exceptions (receiver null checks) from caller JVMS
1071     GraphKit caller(_caller);
1072     SafePointNode* ex_map;
1073     while ((ex_map = caller.pop_exception_state()) != NULL) {
1074       _exits.add_exception_state(ex_map);
1075     }
1076   }
1077   _exits.map()->apply_replaced_nodes();
1078 }
1079 
1080 //-----------------------------create_entry_map-------------------------------
1081 // Initialize our parser map to contain the types at method entry.
1082 // For OSR, the map contains a single RawPtr parameter.
1083 // Initial monitor locking for sync. methods is performed by do_method_entry.
1084 SafePointNode* Parse::create_entry_map() {
1085   // Check for really stupid bail-out cases.
1086   uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
1087   if (len >= 32760) {
1088     C->record_method_not_compilable_all_tiers("too many local variables");
1089     return NULL;
1090   }
1091 
1092   // clear current replaced nodes that are of no use from here on (map was cloned in build_exits).
1093   _caller->map()->delete_replaced_nodes();
1094 
1095   // If this is an inlined method, we may have to do a receiver null check.
1096   if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
1097     GraphKit kit(_caller);
1098     kit.null_check_receiver_before_call(method());
1099     _caller = kit.transfer_exceptions_into_jvms();
1100     if (kit.stopped()) {
1101       _exits.add_exception_states_from(_caller);
1102       _exits.set_jvms(_caller);
1103       return NULL;
1104     }
1105   }
1106 
1107   assert(method() != NULL, "parser must have a method");
1108 
1109   // Create an initial safepoint to hold JVM state during parsing
1110   JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : NULL);
1111   set_map(new SafePointNode(len, jvms));
1112   jvms->set_map(map());
1113   record_for_igvn(map());
1114   assert(jvms->endoff() == len, "correct jvms sizing");
1115 
1116   SafePointNode* inmap = _caller->map();
1117   assert(inmap != NULL, "must have inmap");
1118   // In case of null check on receiver above
1119   map()->transfer_replaced_nodes_from(inmap, _new_idx);
1120 
1121   uint i;
1122 
1123   // Pass thru the predefined input parameters.
1124   for (i = 0; i < TypeFunc::Parms; i++) {
1125     map()->init_req(i, inmap->in(i));
1126   }
1127 
1128   if (depth() == 1) {
1129     assert(map()->memory()->Opcode() == Op_Parm, "");
1130     // Insert the memory aliasing node
1131     set_all_memory(reset_memory());
1132   }
1133   assert(merged_memory(), "");
1134 
1135   // Now add the locals which are initially bound to arguments:
1136   uint arg_size = tf()->domain()->cnt();
1137   ensure_stack(arg_size - TypeFunc::Parms);  // OSR methods have funny args
1138   for (i = TypeFunc::Parms; i < arg_size; i++) {
1139     map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
1140   }
1141 
1142   // Clear out the rest of the map (locals and stack)
1143   for (i = arg_size; i < len; i++) {
1144     map()->init_req(i, top());
1145   }
1146 
1147   SafePointNode* entry_map = stop();
1148   return entry_map;
1149 }
1150 
1151 //-----------------------------do_method_entry--------------------------------
1152 // Emit any code needed in the pseudo-block before BCI zero.
1153 // The main thing to do is lock the receiver of a synchronized method.
1154 void Parse::do_method_entry() {
1155   set_parse_bci(InvocationEntryBci); // Pseudo-BCP
1156   set_sp(0);                      // Java Stack Pointer
1157 
1158   NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
1159 
1160   if (C->env()->dtrace_method_probes()) {
1161     make_dtrace_method_entry(method());
1162   }
1163 
1164   // If the method is synchronized, we need to construct a lock node, attach
1165   // it to the Start node, and pin it there.
1166   if (method()->is_synchronized()) {
1167     // Insert a FastLockNode right after the Start which takes as arguments
1168     // the current thread pointer, the "this" pointer & the address of the
1169     // stack slot pair used for the lock.  The "this" pointer is a projection
1170     // off the start node, but the locking spot has to be constructed by
1171     // creating a ConLNode of 0, and boxing it with a BoxLockNode.  The BoxLockNode
1172     // becomes the second argument to the FastLockNode call.  The
1173     // FastLockNode becomes the new control parent to pin it to the start.
1174 
1175     // Setup Object Pointer
1176     Node *lock_obj = NULL;
1177     if(method()->is_static()) {
1178       ciInstance* mirror = _method->holder()->java_mirror();
1179       const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1180       lock_obj = makecon(t_lock);
1181     } else {                  // Else pass the "this" pointer,
1182       lock_obj = local(0);    // which is Parm0 from StartNode
1183     }
1184     // Clear out dead values from the debug info.
1185     kill_dead_locals();
1186     // Build the FastLockNode
1187     _synch_lock = shared_lock(lock_obj);
1188   }
1189 
1190   // Feed profiling data for parameters to the type system so it can
1191   // propagate it as speculative types
1192   record_profiled_parameters_for_speculation();
1193 
1194   if (depth() == 1) {
1195     increment_and_test_invocation_counter(Tier2CompileThreshold);
1196   }
1197 }
1198 
1199 //------------------------------init_blocks------------------------------------
1200 // Initialize our parser map to contain the types/monitors at method entry.
1201 void Parse::init_blocks() {
1202   // Create the blocks.
1203   _block_count = flow()->block_count();
1204   _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);
1205   Copy::zero_to_bytes(_blocks, sizeof(Block)*_block_count);
1206 
1207   int rpo;
1208 
1209   // Initialize the structs.
1210   for (rpo = 0; rpo < block_count(); rpo++) {
1211     Block* block = rpo_at(rpo);
1212     block->init_node(this, rpo);
1213   }
1214 
1215   // Collect predecessor and successor information.
1216   for (rpo = 0; rpo < block_count(); rpo++) {
1217     Block* block = rpo_at(rpo);
1218     block->init_graph(this);
1219   }
1220 }
1221 
1222 //-------------------------------init_node-------------------------------------
1223 void Parse::Block::init_node(Parse* outer, int rpo) {
1224   _flow = outer->flow()->rpo_at(rpo);
1225   _pred_count = 0;
1226   _preds_parsed = 0;
1227   _count = 0;
1228   assert(pred_count() == 0 && preds_parsed() == 0, "sanity");
1229   assert(!(is_merged() || is_parsed() || is_handler() || has_merged_backedge()), "sanity");
1230   assert(_live_locals.size() == 0, "sanity");
1231 
1232   // entry point has additional predecessor
1233   if (flow()->is_start())  _pred_count++;
1234   assert(flow()->is_start() == (this == outer->start_block()), "");
1235 }
1236 
1237 //-------------------------------init_graph------------------------------------
1238 void Parse::Block::init_graph(Parse* outer) {
1239   // Create the successor list for this parser block.
1240   GrowableArray<ciTypeFlow::Block*>* tfs = flow()->successors();
1241   GrowableArray<ciTypeFlow::Block*>* tfe = flow()->exceptions();
1242   int ns = tfs->length();
1243   int ne = tfe->length();
1244   _num_successors = ns;
1245   _all_successors = ns+ne;
1246   _successors = (ns+ne == 0) ? NULL : NEW_RESOURCE_ARRAY(Block*, ns+ne);
1247   int p = 0;
1248   for (int i = 0; i < ns+ne; i++) {
1249     ciTypeFlow::Block* tf2 = (i < ns) ? tfs->at(i) : tfe->at(i-ns);
1250     Block* block2 = outer->rpo_at(tf2->rpo());
1251     _successors[i] = block2;
1252 
1253     // Accumulate pred info for the other block, too.
1254     if (i < ns) {
1255       block2->_pred_count++;
1256     } else {
1257       block2->_is_handler = true;
1258     }
1259 
1260     #ifdef ASSERT
1261     // A block's successors must be distinguishable by BCI.
1262     // That is, no bytecode is allowed to branch to two different
1263     // clones of the same code location.
1264     for (int j = 0; j < i; j++) {
1265       Block* block1 = _successors[j];
1266       if (block1 == block2)  continue;  // duplicates are OK
1267       assert(block1->start() != block2->start(), "successors have unique bcis");
1268     }
1269     #endif
1270   }
1271 
1272   // Note: We never call next_path_num along exception paths, so they
1273   // never get processed as "ready".  Also, the input phis of exception
1274   // handlers get specially processed, so that
1275 }
1276 
1277 //---------------------------successor_for_bci---------------------------------
1278 Parse::Block* Parse::Block::successor_for_bci(int bci) {
1279   for (int i = 0; i < all_successors(); i++) {
1280     Block* block2 = successor_at(i);
1281     if (block2->start() == bci)  return block2;
1282   }
1283   // We can actually reach here if ciTypeFlow traps out a block
1284   // due to an unloaded class, and concurrently with compilation the
1285   // class is then loaded, so that a later phase of the parser is
1286   // able to see more of the bytecode CFG.  Or, the flow pass and
1287   // the parser can have a minor difference of opinion about executability
1288   // of bytecodes.  For example, "obj.field = null" is executable even
1289   // if the field's type is an unloaded class; the flow pass used to
1290   // make a trap for such code.
1291   return NULL;
1292 }
1293 
1294 
1295 //-----------------------------stack_type_at-----------------------------------
1296 const Type* Parse::Block::stack_type_at(int i) const {
1297   return get_type(flow()->stack_type_at(i));
1298 }
1299 
1300 
1301 //-----------------------------local_type_at-----------------------------------
1302 const Type* Parse::Block::local_type_at(int i) const {
1303   // Make dead locals fall to bottom.
1304   if (_live_locals.size() == 0) {
1305     MethodLivenessResult live_locals = flow()->outer()->method()->liveness_at_bci(start());
1306     // This bitmap can be zero length if we saw a breakpoint.
1307     // In such cases, pretend they are all live.
1308     ((Block*)this)->_live_locals = live_locals;
1309   }
1310   if (_live_locals.size() > 0 && !_live_locals.at(i))
1311     return Type::BOTTOM;
1312 
1313   return get_type(flow()->local_type_at(i));
1314 }
1315 
1316 
1317 #ifndef PRODUCT
1318 
1319 //----------------------------name_for_bc--------------------------------------
1320 // helper method for BytecodeParseHistogram
1321 static const char* name_for_bc(int i) {
1322   return Bytecodes::is_defined(i) ? Bytecodes::name(Bytecodes::cast(i)) : "xxxunusedxxx";
1323 }
1324 
1325 //----------------------------BytecodeParseHistogram------------------------------------
1326 Parse::BytecodeParseHistogram::BytecodeParseHistogram(Parse *p, Compile *c) {
1327   _parser   = p;
1328   _compiler = c;
1329   if( ! _initialized ) { _initialized = true; reset(); }
1330 }
1331 
1332 //----------------------------current_count------------------------------------
1333 int Parse::BytecodeParseHistogram::current_count(BPHType bph_type) {
1334   switch( bph_type ) {
1335   case BPH_transforms: { return _parser->gvn().made_progress(); }
1336   case BPH_values:     { return _parser->gvn().made_new_values(); }
1337   default: { ShouldNotReachHere(); return 0; }
1338   }
1339 }
1340 
1341 //----------------------------initialized--------------------------------------
1342 bool Parse::BytecodeParseHistogram::initialized() { return _initialized; }
1343 
1344 //----------------------------reset--------------------------------------------
1345 void Parse::BytecodeParseHistogram::reset() {
1346   int i = Bytecodes::number_of_codes;
1347   while (i-- > 0) { _bytecodes_parsed[i] = 0; _nodes_constructed[i] = 0; _nodes_transformed[i] = 0; _new_values[i] = 0; }
1348 }
1349 
1350 //----------------------------set_initial_state--------------------------------
1351 // Record info when starting to parse one bytecode
1352 void Parse::BytecodeParseHistogram::set_initial_state( Bytecodes::Code bc ) {
1353   if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1354     _initial_bytecode    = bc;
1355     _initial_node_count  = _compiler->unique();
1356     _initial_transforms  = current_count(BPH_transforms);
1357     _initial_values      = current_count(BPH_values);
1358   }
1359 }
1360 
1361 //----------------------------record_change--------------------------------
1362 // Record results of parsing one bytecode
1363 void Parse::BytecodeParseHistogram::record_change() {
1364   if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1365     ++_bytecodes_parsed[_initial_bytecode];
1366     _nodes_constructed [_initial_bytecode] += (_compiler->unique() - _initial_node_count);
1367     _nodes_transformed [_initial_bytecode] += (current_count(BPH_transforms) - _initial_transforms);
1368     _new_values        [_initial_bytecode] += (current_count(BPH_values)     - _initial_values);
1369   }
1370 }
1371 
1372 
1373 //----------------------------print--------------------------------------------
1374 void Parse::BytecodeParseHistogram::print(float cutoff) {
1375   ResourceMark rm;
1376   // print profile
1377   int total  = 0;
1378   int i      = 0;
1379   for( i = 0; i < Bytecodes::number_of_codes; ++i ) { total += _bytecodes_parsed[i]; }
1380   int abs_sum = 0;
1381   tty->cr();   //0123456789012345678901234567890123456789012345678901234567890123456789
1382   tty->print_cr("Histogram of %d parsed bytecodes:", total);
1383   if( total == 0 ) { return; }
1384   tty->cr();
1385   tty->print_cr("absolute:  count of compiled bytecodes of this type");
1386   tty->print_cr("relative:  percentage contribution to compiled nodes");
1387   tty->print_cr("nodes   :  Average number of nodes constructed per bytecode");
1388   tty->print_cr("rnodes  :  Significance towards total nodes constructed, (nodes*relative)");
1389   tty->print_cr("transforms: Average amount of tranform progress per bytecode compiled");
1390   tty->print_cr("values  :  Average number of node values improved per bytecode");
1391   tty->print_cr("name    :  Bytecode name");
1392   tty->cr();
1393   tty->print_cr("  absolute  relative   nodes  rnodes  transforms  values   name");
1394   tty->print_cr("----------------------------------------------------------------------");
1395   while (--i > 0) {
1396     int       abs = _bytecodes_parsed[i];
1397     float     rel = abs * 100.0F / total;
1398     float   nodes = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_constructed[i])/_bytecodes_parsed[i];
1399     float  rnodes = _bytecodes_parsed[i] == 0 ? 0 :  rel * nodes;
1400     float  xforms = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_transformed[i])/_bytecodes_parsed[i];
1401     float  values = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _new_values       [i])/_bytecodes_parsed[i];
1402     if (cutoff <= rel) {
1403       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));
1404       abs_sum += abs;
1405     }
1406   }
1407   tty->print_cr("----------------------------------------------------------------------");
1408   float rel_sum = abs_sum * 100.0F / total;
1409   tty->print_cr("%10d  %7.2f%%    (cutoff = %.2f%%)", abs_sum, rel_sum, cutoff);
1410   tty->print_cr("----------------------------------------------------------------------");
1411   tty->cr();
1412 }
1413 #endif
1414 
1415 //----------------------------load_state_from----------------------------------
1416 // Load block/map/sp.  But not do not touch iter/bci.
1417 void Parse::load_state_from(Block* block) {
1418   set_block(block);
1419   // load the block's JVM state:
1420   set_map(block->start_map());
1421   set_sp( block->start_sp());
1422 }
1423 
1424 
1425 //-----------------------------record_state------------------------------------
1426 void Parse::Block::record_state(Parse* p) {
1427   assert(!is_merged(), "can only record state once, on 1st inflow");
1428   assert(start_sp() == p->sp(), "stack pointer must agree with ciTypeFlow");
1429   set_start_map(p->stop());
1430 }
1431 
1432 
1433 //------------------------------do_one_block-----------------------------------
1434 void Parse::do_one_block() {
1435   if (TraceOptoParse) {
1436     Block *b = block();
1437     int ns = b->num_successors();
1438     int nt = b->all_successors();
1439 
1440     tty->print("Parsing block #%d at bci [%d,%d), successors: ",
1441                   block()->rpo(), block()->start(), block()->limit());
1442     for (int i = 0; i < nt; i++) {
1443       tty->print((( i < ns) ? " %d" : " %d(e)"), b->successor_at(i)->rpo());
1444     }
1445     if (b->is_loop_head()) tty->print("  lphd");
1446     tty->cr();
1447   }
1448 
1449   assert(block()->is_merged(), "must be merged before being parsed");
1450   block()->mark_parsed();
1451 
1452   // Set iterator to start of block.
1453   iter().reset_to_bci(block()->start());
1454 
1455   CompileLog* log = C->log();
1456 
1457   // Parse bytecodes
1458   while (!stopped() && !failing()) {
1459     iter().next();
1460 
1461     // Learn the current bci from the iterator:
1462     set_parse_bci(iter().cur_bci());
1463 
1464     if (bci() == block()->limit()) {
1465       // Do not walk into the next block until directed by do_all_blocks.
1466       merge(bci());
1467       break;
1468     }
1469     assert(bci() < block()->limit(), "bci still in block");
1470 
1471     if (log != NULL) {
1472       // Output an optional context marker, to help place actions
1473       // that occur during parsing of this BC.  If there is no log
1474       // output until the next context string, this context string
1475       // will be silently ignored.
1476       log->set_context("bc code='%d' bci='%d'", (int)bc(), bci());
1477     }
1478 
1479     if (block()->has_trap_at(bci())) {
1480       // We must respect the flow pass's traps, because it will refuse
1481       // to produce successors for trapping blocks.
1482       int trap_index = block()->flow()->trap_index();
1483       assert(trap_index != 0, "trap index must be valid");
1484       uncommon_trap(trap_index);
1485       break;
1486     }
1487 
1488     NOT_PRODUCT( parse_histogram()->set_initial_state(bc()); );
1489 
1490 #ifdef ASSERT
1491     int pre_bc_sp = sp();
1492     int inputs, depth;
1493     bool have_se = !stopped() && compute_stack_effects(inputs, depth);
1494     assert(!have_se || pre_bc_sp >= inputs, "have enough stack to execute this BC: pre_bc_sp=%d, inputs=%d", pre_bc_sp, inputs);
1495 #endif //ASSERT
1496 
1497     do_one_bytecode();
1498 
1499     assert(!have_se || stopped() || failing() || (sp() - pre_bc_sp) == depth,
1500            "incorrect depth prediction: sp=%d, pre_bc_sp=%d, depth=%d", sp(), pre_bc_sp, depth);
1501 
1502     do_exceptions();
1503 
1504     NOT_PRODUCT( parse_histogram()->record_change(); );
1505 
1506     if (log != NULL)
1507       log->clear_context();  // skip marker if nothing was printed
1508 
1509     // Fall into next bytecode.  Each bytecode normally has 1 sequential
1510     // successor which is typically made ready by visiting this bytecode.
1511     // If the successor has several predecessors, then it is a merge
1512     // point, starts a new basic block, and is handled like other basic blocks.
1513   }
1514 }
1515 
1516 
1517 //------------------------------merge------------------------------------------
1518 void Parse::set_parse_bci(int bci) {
1519   set_bci(bci);
1520   Node_Notes* nn = C->default_node_notes();
1521   if (nn == NULL)  return;
1522 
1523   // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
1524   if (!DebugInlinedCalls && depth() > 1) {
1525     return;
1526   }
1527 
1528   // Update the JVMS annotation, if present.
1529   JVMState* jvms = nn->jvms();
1530   if (jvms != NULL && jvms->bci() != bci) {
1531     // Update the JVMS.
1532     jvms = jvms->clone_shallow(C);
1533     jvms->set_bci(bci);
1534     nn->set_jvms(jvms);
1535   }
1536 }
1537 
1538 //------------------------------merge------------------------------------------
1539 // Merge the current mapping into the basic block starting at bci
1540 void Parse::merge(int target_bci) {
1541   Block* target = successor_for_bci(target_bci);
1542   if (target == NULL) { handle_missing_successor(target_bci); return; }
1543   assert(!target->is_ready(), "our arrival must be expected");
1544   int pnum = target->next_path_num();
1545   merge_common(target, pnum);
1546 }
1547 
1548 //-------------------------merge_new_path--------------------------------------
1549 // Merge the current mapping into the basic block, using a new path
1550 void Parse::merge_new_path(int target_bci) {
1551   Block* target = successor_for_bci(target_bci);
1552   if (target == NULL) { handle_missing_successor(target_bci); return; }
1553   assert(!target->is_ready(), "new path into frozen graph");
1554   int pnum = target->add_new_path();
1555   merge_common(target, pnum);
1556 }
1557 
1558 //-------------------------merge_exception-------------------------------------
1559 // Merge the current mapping into the basic block starting at bci
1560 // The ex_oop must be pushed on the stack, unlike throw_to_exit.
1561 void Parse::merge_exception(int target_bci) {
1562   assert(sp() == 1, "must have only the throw exception on the stack");
1563   Block* target = successor_for_bci(target_bci);
1564   if (target == NULL) { handle_missing_successor(target_bci); return; }
1565   assert(target->is_handler(), "exceptions are handled by special blocks");
1566   int pnum = target->add_new_path();
1567   merge_common(target, pnum);
1568 }
1569 
1570 //--------------------handle_missing_successor---------------------------------
1571 void Parse::handle_missing_successor(int target_bci) {
1572 #ifndef PRODUCT
1573   Block* b = block();
1574   int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
1575   tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
1576 #endif
1577   ShouldNotReachHere();
1578 }
1579 
1580 //--------------------------merge_common---------------------------------------
1581 void Parse::merge_common(Parse::Block* target, int pnum) {
1582   if (TraceOptoParse) {
1583     tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
1584   }
1585 
1586   // Zap extra stack slots to top
1587   assert(sp() == target->start_sp(), "");
1588   clean_stack(sp());
1589 
1590   if (!target->is_merged()) {   // No prior mapping at this bci
1591     if (TraceOptoParse) { tty->print(" with empty state");  }
1592 
1593     // If this path is dead, do not bother capturing it as a merge.
1594     // It is "as if" we had 1 fewer predecessors from the beginning.
1595     if (stopped()) {
1596       if (TraceOptoParse)  tty->print_cr(", but path is dead and doesn't count");
1597       return;
1598     }
1599 
1600     // Make a region if we know there are multiple or unpredictable inputs.
1601     // (Also, if this is a plain fall-through, we might see another region,
1602     // which must not be allowed into this block's map.)
1603     if (pnum > PhiNode::Input         // Known multiple inputs.
1604         || target->is_handler()       // These have unpredictable inputs.
1605         || target->is_loop_head()     // Known multiple inputs
1606         || control()->is_Region()) {  // We must hide this guy.
1607 
1608       int current_bci = bci();
1609       set_parse_bci(target->start()); // Set target bci
1610       if (target->is_SEL_head()) {
1611         DEBUG_ONLY( target->mark_merged_backedge(block()); )
1612         if (target->start() == 0) {
1613           // Add loop predicate for the special case when
1614           // there are backbranches to the method entry.
1615           add_predicate();
1616         }
1617       }
1618       // Add a Region to start the new basic block.  Phis will be added
1619       // later lazily.
1620       int edges = target->pred_count();
1621       if (edges < pnum)  edges = pnum;  // might be a new path!
1622       RegionNode *r = new RegionNode(edges+1);
1623       gvn().set_type(r, Type::CONTROL);
1624       record_for_igvn(r);
1625       // zap all inputs to NULL for debugging (done in Node(uint) constructor)
1626       // for (int j = 1; j < edges+1; j++) { r->init_req(j, NULL); }
1627       r->init_req(pnum, control());
1628       set_control(r);
1629       set_parse_bci(current_bci); // Restore bci
1630     }
1631 
1632     // Convert the existing Parser mapping into a mapping at this bci.
1633     store_state_to(target);
1634     assert(target->is_merged(), "do not come here twice");
1635 
1636   } else {                      // Prior mapping at this bci
1637     if (TraceOptoParse) {  tty->print(" with previous state"); }
1638 #ifdef ASSERT
1639     if (target->is_SEL_head()) {
1640       target->mark_merged_backedge(block());
1641     }
1642 #endif
1643     // We must not manufacture more phis if the target is already parsed.
1644     bool nophi = target->is_parsed();
1645 
1646     SafePointNode* newin = map();// Hang on to incoming mapping
1647     Block* save_block = block(); // Hang on to incoming block;
1648     load_state_from(target);    // Get prior mapping
1649 
1650     assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1651     assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1652     assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1653     assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1654 
1655     // Iterate over my current mapping and the old mapping.
1656     // Where different, insert Phi functions.
1657     // Use any existing Phi functions.
1658     assert(control()->is_Region(), "must be merging to a region");
1659     RegionNode* r = control()->as_Region();
1660 
1661     // Compute where to merge into
1662     // Merge incoming control path
1663     r->init_req(pnum, newin->control());
1664 
1665     if (pnum == 1) {            // Last merge for this Region?
1666       if (!block()->flow()->is_irreducible_entry()) {
1667         Node* result = _gvn.transform_no_reclaim(r);
1668         if (r != result && TraceOptoParse) {
1669           tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1670         }
1671       }
1672       record_for_igvn(r);
1673     }
1674 
1675     // Update all the non-control inputs to map:
1676     assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1677     bool check_elide_phi = target->is_SEL_backedge(save_block);
1678     for (uint j = 1; j < newin->req(); j++) {
1679       Node* m = map()->in(j);   // Current state of target.
1680       Node* n = newin->in(j);   // Incoming change to target state.
1681       PhiNode* phi;
1682       if (m->is_Phi() && m->as_Phi()->region() == r)
1683         phi = m->as_Phi();
1684       else
1685         phi = NULL;
1686       if (m != n) {             // Different; must merge
1687         switch (j) {
1688         // Frame pointer and Return Address never changes
1689         case TypeFunc::FramePtr:// Drop m, use the original value
1690         case TypeFunc::ReturnAdr:
1691           break;
1692         case TypeFunc::Memory:  // Merge inputs to the MergeMem node
1693           assert(phi == NULL, "the merge contains phis, not vice versa");
1694           merge_memory_edges(n->as_MergeMem(), pnum, nophi);
1695           continue;
1696         default:                // All normal stuff
1697           if (phi == NULL) {
1698             const JVMState* jvms = map()->jvms();
1699             if (EliminateNestedLocks &&
1700                 jvms->is_mon(j) && jvms->is_monitor_box(j)) {
1701               // BoxLock nodes are not commoning.
1702               // Use old BoxLock node as merged box.
1703               assert(newin->jvms()->is_monitor_box(j), "sanity");
1704               // This assert also tests that nodes are BoxLock.
1705               assert(BoxLockNode::same_slot(n, m), "sanity");
1706               C->gvn_replace_by(n, m);
1707             } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
1708               phi = ensure_phi(j, nophi);
1709             }
1710           }
1711           break;
1712         }
1713       }
1714       // At this point, n might be top if:
1715       //  - there is no phi (because TypeFlow detected a conflict), or
1716       //  - the corresponding control edges is top (a dead incoming path)
1717       // It is a bug if we create a phi which sees a garbage value on a live path.
1718 
1719       if (phi != NULL) {
1720         assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
1721         assert(phi->region() == r, "");
1722         phi->set_req(pnum, n);  // Then add 'n' to the merge
1723         if (pnum == PhiNode::Input) {
1724           // Last merge for this Phi.
1725           // So far, Phis have had a reasonable type from ciTypeFlow.
1726           // Now _gvn will join that with the meet of current inputs.
1727           // BOTTOM is never permissible here, 'cause pessimistically
1728           // Phis of pointers cannot lose the basic pointer type.
1729           debug_only(const Type* bt1 = phi->bottom_type());
1730           assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
1731           map()->set_req(j, _gvn.transform_no_reclaim(phi));
1732           debug_only(const Type* bt2 = phi->bottom_type());
1733           assert(bt2->higher_equal_speculative(bt1), "must be consistent with type-flow");
1734           record_for_igvn(phi);
1735         }
1736       }
1737     } // End of for all values to be merged
1738 
1739     if (pnum == PhiNode::Input &&
1740         !r->in(0)) {         // The occasional useless Region
1741       assert(control() == r, "");
1742       set_control(r->nonnull_req());
1743     }
1744 
1745     map()->merge_replaced_nodes_with(newin);
1746 
1747     // newin has been subsumed into the lazy merge, and is now dead.
1748     set_block(save_block);
1749 
1750     stop();                     // done with this guy, for now
1751   }
1752 
1753   if (TraceOptoParse) {
1754     tty->print_cr(" on path %d", pnum);
1755   }
1756 
1757   // Done with this parser state.
1758   assert(stopped(), "");
1759 }
1760 
1761 
1762 //--------------------------merge_memory_edges---------------------------------
1763 void Parse::merge_memory_edges(MergeMemNode* n, int pnum, bool nophi) {
1764   // (nophi means we must not create phis, because we already parsed here)
1765   assert(n != NULL, "");
1766   // Merge the inputs to the MergeMems
1767   MergeMemNode* m = merged_memory();
1768 
1769   assert(control()->is_Region(), "must be merging to a region");
1770   RegionNode* r = control()->as_Region();
1771 
1772   PhiNode* base = NULL;
1773   MergeMemNode* remerge = NULL;
1774   for (MergeMemStream mms(m, n); mms.next_non_empty2(); ) {
1775     Node *p = mms.force_memory();
1776     Node *q = mms.memory2();
1777     if (mms.is_empty() && nophi) {
1778       // Trouble:  No new splits allowed after a loop body is parsed.
1779       // Instead, wire the new split into a MergeMem on the backedge.
1780       // The optimizer will sort it out, slicing the phi.
1781       if (remerge == NULL) {
1782         assert(base != NULL, "");
1783         assert(base->in(0) != NULL, "should not be xformed away");
1784         remerge = MergeMemNode::make(base->in(pnum));
1785         gvn().set_type(remerge, Type::MEMORY);
1786         base->set_req(pnum, remerge);
1787       }
1788       remerge->set_memory_at(mms.alias_idx(), q);
1789       continue;
1790     }
1791     assert(!q->is_MergeMem(), "");
1792     PhiNode* phi;
1793     if (p != q) {
1794       phi = ensure_memory_phi(mms.alias_idx(), nophi);
1795     } else {
1796       if (p->is_Phi() && p->as_Phi()->region() == r)
1797         phi = p->as_Phi();
1798       else
1799         phi = NULL;
1800     }
1801     // Insert q into local phi
1802     if (phi != NULL) {
1803       assert(phi->region() == r, "");
1804       p = phi;
1805       phi->set_req(pnum, q);
1806       if (mms.at_base_memory()) {
1807         base = phi;  // delay transforming it
1808       } else if (pnum == 1) {
1809         record_for_igvn(phi);
1810         p = _gvn.transform_no_reclaim(phi);
1811       }
1812       mms.set_memory(p);// store back through the iterator
1813     }
1814   }
1815   // Transform base last, in case we must fiddle with remerging.
1816   if (base != NULL && pnum == 1) {
1817     record_for_igvn(base);
1818     m->set_base_memory( _gvn.transform_no_reclaim(base) );
1819   }
1820 }
1821 
1822 
1823 //------------------------ensure_phis_everywhere-------------------------------
1824 void Parse::ensure_phis_everywhere() {
1825   ensure_phi(TypeFunc::I_O);
1826 
1827   // Ensure a phi on all currently known memories.
1828   for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
1829     ensure_memory_phi(mms.alias_idx());
1830     debug_only(mms.set_memory());  // keep the iterator happy
1831   }
1832 
1833   // Note:  This is our only chance to create phis for memory slices.
1834   // If we miss a slice that crops up later, it will have to be
1835   // merged into the base-memory phi that we are building here.
1836   // Later, the optimizer will comb out the knot, and build separate
1837   // phi-loops for each memory slice that matters.
1838 
1839   // Monitors must nest nicely and not get confused amongst themselves.
1840   // Phi-ify everything up to the monitors, though.
1841   uint monoff = map()->jvms()->monoff();
1842   uint nof_monitors = map()->jvms()->nof_monitors();
1843 
1844   assert(TypeFunc::Parms == map()->jvms()->locoff(), "parser map should contain only youngest jvms");
1845   bool check_elide_phi = block()->is_SEL_head();
1846   for (uint i = TypeFunc::Parms; i < monoff; i++) {
1847     if (!check_elide_phi || !block()->can_elide_SEL_phi(i)) {
1848       ensure_phi(i);
1849     }
1850   }
1851 
1852   // Even monitors need Phis, though they are well-structured.
1853   // This is true for OSR methods, and also for the rare cases where
1854   // a monitor object is the subject of a replace_in_map operation.
1855   // See bugs 4426707 and 5043395.
1856   for (uint m = 0; m < nof_monitors; m++) {
1857     ensure_phi(map()->jvms()->monitor_obj_offset(m));
1858   }
1859 }
1860 
1861 
1862 //-----------------------------add_new_path------------------------------------
1863 // Add a previously unaccounted predecessor to this block.
1864 int Parse::Block::add_new_path() {
1865   // If there is no map, return the lowest unused path number.
1866   if (!is_merged())  return pred_count()+1;  // there will be a map shortly
1867 
1868   SafePointNode* map = start_map();
1869   if (!map->control()->is_Region())
1870     return pred_count()+1;  // there may be a region some day
1871   RegionNode* r = map->control()->as_Region();
1872 
1873   // Add new path to the region.
1874   uint pnum = r->req();
1875   r->add_req(NULL);
1876 
1877   for (uint i = 1; i < map->req(); i++) {
1878     Node* n = map->in(i);
1879     if (i == TypeFunc::Memory) {
1880       // Ensure a phi on all currently known memories.
1881       for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
1882         Node* phi = mms.memory();
1883         if (phi->is_Phi() && phi->as_Phi()->region() == r) {
1884           assert(phi->req() == pnum, "must be same size as region");
1885           phi->add_req(NULL);
1886         }
1887       }
1888     } else {
1889       if (n->is_Phi() && n->as_Phi()->region() == r) {
1890         assert(n->req() == pnum, "must be same size as region");
1891         n->add_req(NULL);
1892       }
1893     }
1894   }
1895 
1896   return pnum;
1897 }
1898 
1899 //------------------------------ensure_phi-------------------------------------
1900 // Turn the idx'th entry of the current map into a Phi
1901 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
1902   SafePointNode* map = this->map();
1903   Node* region = map->control();
1904   assert(region->is_Region(), "");
1905 
1906   Node* o = map->in(idx);
1907   assert(o != NULL, "");
1908 
1909   if (o == top())  return NULL; // TOP always merges into TOP
1910 
1911   if (o->is_Phi() && o->as_Phi()->region() == region) {
1912     return o->as_Phi();
1913   }
1914 
1915   // Now use a Phi here for merging
1916   assert(!nocreate, "Cannot build a phi for a block already parsed.");
1917   const JVMState* jvms = map->jvms();
1918   const Type* t = NULL;
1919   if (jvms->is_loc(idx)) {
1920     t = block()->local_type_at(idx - jvms->locoff());
1921   } else if (jvms->is_stk(idx)) {
1922     t = block()->stack_type_at(idx - jvms->stkoff());
1923   } else if (jvms->is_mon(idx)) {
1924     assert(!jvms->is_monitor_box(idx), "no phis for boxes");
1925     t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
1926   } else if ((uint)idx < TypeFunc::Parms) {
1927     t = o->bottom_type();  // Type::RETURN_ADDRESS or such-like.
1928   } else {
1929     assert(false, "no type information for this phi");
1930   }
1931 
1932   // If the type falls to bottom, then this must be a local that
1933   // is mixing ints and oops or some such.  Forcing it to top
1934   // makes it go dead.
1935   if (t == Type::BOTTOM) {
1936     map->set_req(idx, top());
1937     return NULL;
1938   }
1939 
1940   // Do not create phis for top either.
1941   // A top on a non-null control flow must be an unused even after the.phi.
1942   if (t == Type::TOP || t == Type::HALF) {
1943     map->set_req(idx, top());
1944     return NULL;
1945   }
1946 
1947   PhiNode* phi = PhiNode::make(region, o, t);
1948   gvn().set_type(phi, t);
1949   if (C->do_escape_analysis()) record_for_igvn(phi);
1950   map->set_req(idx, phi);
1951   return phi;
1952 }
1953 
1954 //--------------------------ensure_memory_phi----------------------------------
1955 // Turn the idx'th slice of the current memory into a Phi
1956 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
1957   MergeMemNode* mem = merged_memory();
1958   Node* region = control();
1959   assert(region->is_Region(), "");
1960 
1961   Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
1962   assert(o != NULL && o != top(), "");
1963 
1964   PhiNode* phi;
1965   if (o->is_Phi() && o->as_Phi()->region() == region) {
1966     phi = o->as_Phi();
1967     if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
1968       // clone the shared base memory phi to make a new memory split
1969       assert(!nocreate, "Cannot build a phi for a block already parsed.");
1970       const Type* t = phi->bottom_type();
1971       const TypePtr* adr_type = C->get_adr_type(idx);
1972       phi = phi->slice_memory(adr_type);
1973       gvn().set_type(phi, t);
1974     }
1975     return phi;
1976   }
1977 
1978   // Now use a Phi here for merging
1979   assert(!nocreate, "Cannot build a phi for a block already parsed.");
1980   const Type* t = o->bottom_type();
1981   const TypePtr* adr_type = C->get_adr_type(idx);
1982   phi = PhiNode::make(region, o, t, adr_type);
1983   gvn().set_type(phi, t);
1984   if (idx == Compile::AliasIdxBot)
1985     mem->set_base_memory(phi);
1986   else
1987     mem->set_memory_at(idx, phi);
1988   return phi;
1989 }
1990 
1991 //------------------------------call_register_finalizer-----------------------
1992 // Check the klass of the receiver and call register_finalizer if the
1993 // class need finalization.
1994 void Parse::call_register_finalizer() {
1995   Node* receiver = local(0);
1996   assert(receiver != NULL && receiver->bottom_type()->isa_instptr() != NULL,
1997          "must have non-null instance type");
1998 
1999   const TypeInstPtr *tinst = receiver->bottom_type()->isa_instptr();
2000   if (tinst != NULL && tinst->klass()->is_loaded() && !tinst->klass_is_exact()) {
2001     // The type isn't known exactly so see if CHA tells us anything.
2002     ciInstanceKlass* ik = tinst->klass()->as_instance_klass();
2003     if (!Dependencies::has_finalizable_subclass(ik)) {
2004       // No finalizable subclasses so skip the dynamic check.
2005       C->dependencies()->assert_has_no_finalizable_subclasses(ik);
2006       return;
2007     }
2008   }
2009 
2010   // Insert a dynamic test for whether the instance needs
2011   // finalization.  In general this will fold up since the concrete
2012   // class is often visible so the access flags are constant.
2013   Node* klass_addr = basic_plus_adr( receiver, receiver, oopDesc::klass_offset_in_bytes() );
2014   Node* klass = _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), klass_addr, TypeInstPtr::KLASS));
2015 
2016   Node* access_flags_addr = basic_plus_adr(klass, klass, in_bytes(Klass::access_flags_offset()));
2017   Node* access_flags = make_load(NULL, access_flags_addr, TypeInt::INT, T_INT, MemNode::unordered);
2018 
2019   Node* mask  = _gvn.transform(new AndINode(access_flags, intcon(JVM_ACC_HAS_FINALIZER)));
2020   Node* check = _gvn.transform(new CmpINode(mask, intcon(0)));
2021   Node* test  = _gvn.transform(new BoolNode(check, BoolTest::ne));
2022 
2023   IfNode* iff = create_and_map_if(control(), test, PROB_MAX, COUNT_UNKNOWN);
2024 
2025   RegionNode* result_rgn = new RegionNode(3);
2026   record_for_igvn(result_rgn);
2027 
2028   Node *skip_register = _gvn.transform(new IfFalseNode(iff));
2029   result_rgn->init_req(1, skip_register);
2030 
2031   Node *needs_register = _gvn.transform(new IfTrueNode(iff));
2032   set_control(needs_register);
2033   if (stopped()) {
2034     // There is no slow path.
2035     result_rgn->init_req(2, top());
2036   } else {
2037     Node *call = make_runtime_call(RC_NO_LEAF,
2038                                    OptoRuntime::register_finalizer_Type(),
2039                                    OptoRuntime::register_finalizer_Java(),
2040                                    NULL, TypePtr::BOTTOM,
2041                                    receiver);
2042     make_slow_call_ex(call, env()->Throwable_klass(), true);
2043 
2044     Node* fast_io  = call->in(TypeFunc::I_O);
2045     Node* fast_mem = call->in(TypeFunc::Memory);
2046     // These two phis are pre-filled with copies of of the fast IO and Memory
2047     Node* io_phi   = PhiNode::make(result_rgn, fast_io,  Type::ABIO);
2048     Node* mem_phi  = PhiNode::make(result_rgn, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
2049 
2050     result_rgn->init_req(2, control());
2051     io_phi    ->init_req(2, i_o());
2052     mem_phi   ->init_req(2, reset_memory());
2053 
2054     set_all_memory( _gvn.transform(mem_phi) );
2055     set_i_o(        _gvn.transform(io_phi) );
2056   }
2057 
2058   set_control( _gvn.transform(result_rgn) );
2059 }
2060 
2061 // Add check to deoptimize if RTM state is not ProfileRTM
2062 void Parse::rtm_deopt() {
2063 #if INCLUDE_RTM_OPT
2064   if (C->profile_rtm()) {
2065     assert(C->method() != NULL, "only for normal compilations");
2066     assert(!C->method()->method_data()->is_empty(), "MDO is needed to record RTM state");
2067     assert(depth() == 1, "generate check only for main compiled method");
2068 
2069     // Set starting bci for uncommon trap.
2070     set_parse_bci(is_osr_parse() ? osr_bci() : 0);
2071 
2072     // Load the rtm_state from the MethodData.
2073     const TypePtr* adr_type = TypeMetadataPtr::make(C->method()->method_data());
2074     Node* mdo = makecon(adr_type);
2075     int offset = MethodData::rtm_state_offset_in_bytes();
2076     Node* adr_node = basic_plus_adr(mdo, mdo, offset);
2077     Node* rtm_state = make_load(control(), adr_node, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
2078 
2079     // Separate Load from Cmp by Opaque.
2080     // In expand_macro_nodes() it will be replaced either
2081     // with this load when there are locks in the code
2082     // or with ProfileRTM (cmp->in(2)) otherwise so that
2083     // the check will fold.
2084     Node* profile_state = makecon(TypeInt::make(ProfileRTM));
2085     Node* opq   = _gvn.transform( new Opaque3Node(C, rtm_state, Opaque3Node::RTM_OPT) );
2086     Node* chk   = _gvn.transform( new CmpINode(opq, profile_state) );
2087     Node* tst   = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
2088     // Branch to failure if state was changed
2089     { BuildCutout unless(this, tst, PROB_ALWAYS);
2090       uncommon_trap(Deoptimization::Reason_rtm_state_change,
2091                     Deoptimization::Action_make_not_entrant);
2092     }
2093   }
2094 #endif
2095 }
2096 
2097 void Parse::decrement_age() {
2098   MethodCounters* mc = method()->ensure_method_counters();
2099   if (mc == NULL) {
2100     C->record_failure("Must have MCs");
2101     return;
2102   }
2103   assert(!is_osr_parse(), "Not doing this for OSRs");
2104 
2105   // Set starting bci for uncommon trap.
2106   set_parse_bci(0);
2107 
2108   const TypePtr* adr_type = TypeRawPtr::make((address)mc);
2109   Node* mc_adr = makecon(adr_type);
2110   Node* cnt_adr = basic_plus_adr(mc_adr, mc_adr, in_bytes(MethodCounters::nmethod_age_offset()));
2111   Node* cnt = make_load(control(), cnt_adr, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
2112   Node* decr = _gvn.transform(new SubINode(cnt, makecon(TypeInt::ONE)));
2113   store_to_memory(control(), cnt_adr, decr, T_INT, adr_type, MemNode::unordered);
2114   Node *chk   = _gvn.transform(new CmpINode(decr, makecon(TypeInt::ZERO)));
2115   Node* tst   = _gvn.transform(new BoolNode(chk, BoolTest::gt));
2116   { BuildCutout unless(this, tst, PROB_ALWAYS);
2117     uncommon_trap(Deoptimization::Reason_tenured,
2118                   Deoptimization::Action_make_not_entrant);
2119   }
2120 }
2121 
2122 //------------------------------return_current---------------------------------
2123 // Append current _map to _exit_return
2124 void Parse::return_current(Node* value) {
2125   if (RegisterFinalizersAtInit &&
2126       method()->intrinsic_id() == vmIntrinsics::_Object_init) {
2127     call_register_finalizer();
2128   }
2129 
2130   // Do not set_parse_bci, so that return goo is credited to the return insn.
2131   set_bci(InvocationEntryBci);
2132   if (method()->is_synchronized() && GenerateSynchronizationCode) {
2133     shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
2134   }
2135   if (C->env()->dtrace_method_probes()) {
2136     make_dtrace_method_exit(method());
2137   }
2138   SafePointNode* exit_return = _exits.map();
2139   exit_return->in( TypeFunc::Control  )->add_req( control() );
2140   exit_return->in( TypeFunc::I_O      )->add_req( i_o    () );
2141   Node *mem = exit_return->in( TypeFunc::Memory   );
2142   for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
2143     if (mms.is_empty()) {
2144       // get a copy of the base memory, and patch just this one input
2145       const TypePtr* adr_type = mms.adr_type(C);
2146       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
2147       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
2148       gvn().set_type_bottom(phi);
2149       phi->del_req(phi->req()-1);  // prepare to re-patch
2150       mms.set_memory(phi);
2151     }
2152     mms.memory()->add_req(mms.memory2());
2153   }
2154 
2155   // frame pointer is always same, already captured
2156   if (value != NULL) {
2157     // If returning oops to an interface-return, there is a silent free
2158     // cast from oop to interface allowed by the Verifier.  Make it explicit
2159     // here.
2160     Node* phi = _exits.argument(0);
2161     const TypeInstPtr *tr = phi->bottom_type()->isa_instptr();
2162     if (tr && tr->klass()->is_loaded() &&
2163         tr->klass()->is_interface()) {
2164       const TypeInstPtr *tp = value->bottom_type()->isa_instptr();
2165       if (tp && tp->klass()->is_loaded() &&
2166           !tp->klass()->is_interface()) {
2167         // sharpen the type eagerly; this eases certain assert checking
2168         if (tp->higher_equal(TypeInstPtr::NOTNULL))
2169           tr = tr->join_speculative(TypeInstPtr::NOTNULL)->is_instptr();
2170         value = _gvn.transform(new CheckCastPPNode(0, value, tr));
2171       }
2172     } else {
2173       // Also handle returns of oop-arrays to an arrays-of-interface return
2174       const TypeInstPtr* phi_tip;
2175       const TypeInstPtr* val_tip;
2176       Type::get_arrays_base_elements(phi->bottom_type(), value->bottom_type(), &phi_tip, &val_tip);
2177       if (phi_tip != NULL && phi_tip->is_loaded() && phi_tip->klass()->is_interface() &&
2178           val_tip != NULL && val_tip->is_loaded() && !val_tip->klass()->is_interface()) {
2179         value = _gvn.transform(new CheckCastPPNode(0, value, phi->bottom_type()));
2180       }
2181     }
2182     phi->add_req(value);
2183   }
2184 
2185   if (_first_return) {
2186     _exits.map()->transfer_replaced_nodes_from(map(), _new_idx);
2187     _first_return = false;
2188   } else {
2189     _exits.map()->merge_replaced_nodes_with(map());
2190   }
2191 
2192   stop_and_kill_map();          // This CFG path dies here
2193 }
2194 
2195 
2196 //------------------------------add_safepoint----------------------------------
2197 void Parse::add_safepoint() {
2198   // See if we can avoid this safepoint.  No need for a SafePoint immediately
2199   // after a Call (except Leaf Call) or another SafePoint.
2200   Node *proj = control();
2201   bool add_poll_param = SafePointNode::needs_polling_address_input();
2202   uint parms = add_poll_param ? TypeFunc::Parms+1 : TypeFunc::Parms;
2203   if( proj->is_Proj() ) {
2204     Node *n0 = proj->in(0);
2205     if( n0->is_Catch() ) {
2206       n0 = n0->in(0)->in(0);
2207       assert( n0->is_Call(), "expect a call here" );
2208     }
2209     if( n0->is_Call() ) {
2210       if( n0->as_Call()->guaranteed_safepoint() )
2211         return;
2212     } else if( n0->is_SafePoint() && n0->req() >= parms ) {
2213       return;
2214     }
2215   }
2216 
2217   // Clear out dead values from the debug info.
2218   kill_dead_locals();
2219 
2220   // Clone the JVM State
2221   SafePointNode *sfpnt = new SafePointNode(parms, NULL);
2222 
2223   // Capture memory state BEFORE a SafePoint.  Since we can block at a
2224   // SafePoint we need our GC state to be safe; i.e. we need all our current
2225   // write barriers (card marks) to not float down after the SafePoint so we
2226   // must read raw memory.  Likewise we need all oop stores to match the card
2227   // marks.  If deopt can happen, we need ALL stores (we need the correct JVM
2228   // state on a deopt).
2229 
2230   // We do not need to WRITE the memory state after a SafePoint.  The control
2231   // edge will keep card-marks and oop-stores from floating up from below a
2232   // SafePoint and our true dependency added here will keep them from floating
2233   // down below a SafePoint.
2234 
2235   // Clone the current memory state
2236   Node* mem = MergeMemNode::make(map()->memory());
2237 
2238   mem = _gvn.transform(mem);
2239 
2240   // Pass control through the safepoint
2241   sfpnt->init_req(TypeFunc::Control  , control());
2242   // Fix edges normally used by a call
2243   sfpnt->init_req(TypeFunc::I_O      , top() );
2244   sfpnt->init_req(TypeFunc::Memory   , mem   );
2245   sfpnt->init_req(TypeFunc::ReturnAdr, top() );
2246   sfpnt->init_req(TypeFunc::FramePtr , top() );
2247 
2248   // Create a node for the polling address
2249   if( add_poll_param ) {
2250     Node *polladr = ConPNode::make((address)os::get_polling_page());
2251     sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
2252   }
2253 
2254   // Fix up the JVM State edges
2255   add_safepoint_edges(sfpnt);
2256   Node *transformed_sfpnt = _gvn.transform(sfpnt);
2257   set_control(transformed_sfpnt);
2258 
2259   // Provide an edge from root to safepoint.  This makes the safepoint
2260   // appear useful until the parse has completed.
2261   if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
2262     assert(C->root() != NULL, "Expect parse is still valid");
2263     C->root()->add_prec(transformed_sfpnt);
2264   }
2265 }
2266 
2267 #ifndef PRODUCT
2268 //------------------------show_parse_info--------------------------------------
2269 void Parse::show_parse_info() {
2270   InlineTree* ilt = NULL;
2271   if (C->ilt() != NULL) {
2272     JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
2273     ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
2274   }
2275   if (PrintCompilation && Verbose) {
2276     if (depth() == 1) {
2277       if( ilt->count_inlines() ) {
2278         tty->print("    __inlined %d (%d bytes)", ilt->count_inlines(),
2279                      ilt->count_inline_bcs());
2280         tty->cr();
2281       }
2282     } else {
2283       if (method()->is_synchronized())         tty->print("s");
2284       if (method()->has_exception_handlers())  tty->print("!");
2285       // Check this is not the final compiled version
2286       if (C->trap_can_recompile()) {
2287         tty->print("-");
2288       } else {
2289         tty->print(" ");
2290       }
2291       method()->print_short_name();
2292       if (is_osr_parse()) {
2293         tty->print(" @ %d", osr_bci());
2294       }
2295       tty->print(" (%d bytes)",method()->code_size());
2296       if (ilt->count_inlines()) {
2297         tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2298                    ilt->count_inline_bcs());
2299       }
2300       tty->cr();
2301     }
2302   }
2303   if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
2304     // Print that we succeeded; suppress this message on the first osr parse.
2305 
2306     if (method()->is_synchronized())         tty->print("s");
2307     if (method()->has_exception_handlers())  tty->print("!");
2308     // Check this is not the final compiled version
2309     if (C->trap_can_recompile() && depth() == 1) {
2310       tty->print("-");
2311     } else {
2312       tty->print(" ");
2313     }
2314     if( depth() != 1 ) { tty->print("   "); }  // missing compile count
2315     for (int i = 1; i < depth(); ++i) { tty->print("  "); }
2316     method()->print_short_name();
2317     if (is_osr_parse()) {
2318       tty->print(" @ %d", osr_bci());
2319     }
2320     if (ilt->caller_bci() != -1) {
2321       tty->print(" @ %d", ilt->caller_bci());
2322     }
2323     tty->print(" (%d bytes)",method()->code_size());
2324     if (ilt->count_inlines()) {
2325       tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2326                  ilt->count_inline_bcs());
2327     }
2328     tty->cr();
2329   }
2330 }
2331 
2332 
2333 //------------------------------dump-------------------------------------------
2334 // Dump information associated with the bytecodes of current _method
2335 void Parse::dump() {
2336   if( method() != NULL ) {
2337     // Iterate over bytecodes
2338     ciBytecodeStream iter(method());
2339     for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
2340       dump_bci( iter.cur_bci() );
2341       tty->cr();
2342     }
2343   }
2344 }
2345 
2346 // Dump information associated with a byte code index, 'bci'
2347 void Parse::dump_bci(int bci) {
2348   // Output info on merge-points, cloning, and within _jsr..._ret
2349   // NYI
2350   tty->print(" bci:%d", bci);
2351 }
2352 
2353 #endif