src/share/vm/opto/parse1.cpp

Fri, 16 Oct 2009 02:05:46 -0700

author
ysr
date
Fri, 16 Oct 2009 02:05:46 -0700
changeset 1462
39b01ab7035a
parent 1426
3a2aa26bdc58
child 1505
87b2fdd4bf98
permissions
-rw-r--r--

6888898: CMS: ReduceInitialCardMarks unsafe in the presence of cms precleaning
6889757: G1: enable card mark elision for initializing writes from compiled code (ReduceInitialCardMarks)
Summary: Defer the (compiler-elided) card-mark upon a slow-path allocation until after the store and before the next subsequent safepoint; G1 now answers yes to can_elide_tlab_write_barriers().
Reviewed-by: jcoomes, kvn, never

     1 /*
     2  * Copyright 1997-2009 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
    20  * CA 95054 USA or visit www.sun.com if you need additional information or
    21  * have any questions.
    22  *
    23  */
    25 #include "incls/_precompiled.incl"
    26 #include "incls/_parse1.cpp.incl"
    28 // Static array so we can figure out which bytecodes stop us from compiling
    29 // the most. Some of the non-static variables are needed in bytecodeInfo.cpp
    30 // and eventually should be encapsulated in a proper class (gri 8/18/98).
    32 int nodes_created              = 0;
    33 int methods_parsed             = 0;
    34 int methods_seen               = 0;
    35 int blocks_parsed              = 0;
    36 int blocks_seen                = 0;
    38 int explicit_null_checks_inserted = 0;
    39 int explicit_null_checks_elided   = 0;
    40 int all_null_checks_found         = 0, implicit_null_checks              = 0;
    41 int implicit_null_throws          = 0;
    43 int reclaim_idx  = 0;
    44 int reclaim_in   = 0;
    45 int reclaim_node = 0;
    47 #ifndef PRODUCT
    48 bool Parse::BytecodeParseHistogram::_initialized = false;
    49 uint Parse::BytecodeParseHistogram::_bytecodes_parsed [Bytecodes::number_of_codes];
    50 uint Parse::BytecodeParseHistogram::_nodes_constructed[Bytecodes::number_of_codes];
    51 uint Parse::BytecodeParseHistogram::_nodes_transformed[Bytecodes::number_of_codes];
    52 uint Parse::BytecodeParseHistogram::_new_values       [Bytecodes::number_of_codes];
    53 #endif
    55 //------------------------------print_statistics-------------------------------
    56 #ifndef PRODUCT
    57 void Parse::print_statistics() {
    58   tty->print_cr("--- Compiler Statistics ---");
    59   tty->print("Methods seen: %d  Methods parsed: %d", methods_seen, methods_parsed);
    60   tty->print("  Nodes created: %d", nodes_created);
    61   tty->cr();
    62   if (methods_seen != methods_parsed)
    63     tty->print_cr("Reasons for parse failures (NOT cumulative):");
    64   tty->print_cr("Blocks parsed: %d  Blocks seen: %d", blocks_parsed, blocks_seen);
    66   if( explicit_null_checks_inserted )
    67     tty->print_cr("%d original NULL checks - %d elided (%2d%%); optimizer leaves %d,", explicit_null_checks_inserted, explicit_null_checks_elided, (100*explicit_null_checks_elided)/explicit_null_checks_inserted, all_null_checks_found);
    68   if( all_null_checks_found )
    69     tty->print_cr("%d made implicit (%2d%%)", implicit_null_checks,
    70                   (100*implicit_null_checks)/all_null_checks_found);
    71   if( implicit_null_throws )
    72     tty->print_cr("%d implicit null exceptions at runtime",
    73                   implicit_null_throws);
    75   if( PrintParseStatistics && BytecodeParseHistogram::initialized() ) {
    76     BytecodeParseHistogram::print();
    77   }
    78 }
    79 #endif
    81 //------------------------------ON STACK REPLACEMENT---------------------------
    83 // Construct a node which can be used to get incoming state for
    84 // on stack replacement.
    85 Node *Parse::fetch_interpreter_state(int index,
    86                                      BasicType bt,
    87                                      Node *local_addrs,
    88                                      Node *local_addrs_base) {
    89   Node *mem = memory(Compile::AliasIdxRaw);
    90   Node *adr = basic_plus_adr( local_addrs_base, local_addrs, -index*wordSize );
    92   // Very similar to LoadNode::make, except we handle un-aligned longs and
    93   // doubles on Sparc.  Intel can handle them just fine directly.
    94   Node *l;
    95   switch( bt ) {                // Signature is flattened
    96   case T_INT:     l = new (C, 3) LoadINode( 0, mem, adr, TypeRawPtr::BOTTOM ); break;
    97   case T_FLOAT:   l = new (C, 3) LoadFNode( 0, mem, adr, TypeRawPtr::BOTTOM ); break;
    98   case T_ADDRESS: l = new (C, 3) LoadPNode( 0, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM  ); break;
    99   case T_OBJECT:  l = new (C, 3) LoadPNode( 0, mem, adr, TypeRawPtr::BOTTOM, TypeInstPtr::BOTTOM ); break;
   100   case T_LONG:
   101   case T_DOUBLE: {
   102     // Since arguments are in reverse order, the argument address 'adr'
   103     // refers to the back half of the long/double.  Recompute adr.
   104     adr = basic_plus_adr( local_addrs_base, local_addrs, -(index+1)*wordSize );
   105     if( Matcher::misaligned_doubles_ok ) {
   106       l = (bt == T_DOUBLE)
   107         ? (Node*)new (C, 3) LoadDNode( 0, mem, adr, TypeRawPtr::BOTTOM )
   108         : (Node*)new (C, 3) LoadLNode( 0, mem, adr, TypeRawPtr::BOTTOM );
   109     } else {
   110       l = (bt == T_DOUBLE)
   111         ? (Node*)new (C, 3) LoadD_unalignedNode( 0, mem, adr, TypeRawPtr::BOTTOM )
   112         : (Node*)new (C, 3) LoadL_unalignedNode( 0, mem, adr, TypeRawPtr::BOTTOM );
   113     }
   114     break;
   115   }
   116   default: ShouldNotReachHere();
   117   }
   118   return _gvn.transform(l);
   119 }
   121 // Helper routine to prevent the interpreter from handing
   122 // unexpected typestate to an OSR method.
   123 // The Node l is a value newly dug out of the interpreter frame.
   124 // The type is the type predicted by ciTypeFlow.  Note that it is
   125 // not a general type, but can only come from Type::get_typeflow_type.
   126 // The safepoint is a map which will feed an uncommon trap.
   127 Node* Parse::check_interpreter_type(Node* l, const Type* type,
   128                                     SafePointNode* &bad_type_exit) {
   130   const TypeOopPtr* tp = type->isa_oopptr();
   132   // TypeFlow may assert null-ness if a type appears unloaded.
   133   if (type == TypePtr::NULL_PTR ||
   134       (tp != NULL && !tp->klass()->is_loaded())) {
   135     // Value must be null, not a real oop.
   136     Node* chk = _gvn.transform( new (C, 3) CmpPNode(l, null()) );
   137     Node* tst = _gvn.transform( new (C, 2) BoolNode(chk, BoolTest::eq) );
   138     IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
   139     set_control(_gvn.transform( new (C, 1) IfTrueNode(iff) ));
   140     Node* bad_type = _gvn.transform( new (C, 1) IfFalseNode(iff) );
   141     bad_type_exit->control()->add_req(bad_type);
   142     l = null();
   143   }
   145   // Typeflow can also cut off paths from the CFG, based on
   146   // types which appear unloaded, or call sites which appear unlinked.
   147   // When paths are cut off, values at later merge points can rise
   148   // toward more specific classes.  Make sure these specific classes
   149   // are still in effect.
   150   if (tp != NULL && tp->klass() != C->env()->Object_klass()) {
   151     // TypeFlow asserted a specific object type.  Value must have that type.
   152     Node* bad_type_ctrl = NULL;
   153     l = gen_checkcast(l, makecon(TypeKlassPtr::make(tp->klass())), &bad_type_ctrl);
   154     bad_type_exit->control()->add_req(bad_type_ctrl);
   155   }
   157   BasicType bt_l = _gvn.type(l)->basic_type();
   158   BasicType bt_t = type->basic_type();
   159   assert(_gvn.type(l)->higher_equal(type), "must constrain OSR typestate");
   160   return l;
   161 }
   163 // Helper routine which sets up elements of the initial parser map when
   164 // performing a parse for on stack replacement.  Add values into map.
   165 // The only parameter contains the address of a interpreter arguments.
   166 void Parse::load_interpreter_state(Node* osr_buf) {
   167   int index;
   168   int max_locals = jvms()->loc_size();
   169   int max_stack  = jvms()->stk_size();
   172   // Mismatch between method and jvms can occur since map briefly held
   173   // an OSR entry state (which takes up one RawPtr word).
   174   assert(max_locals == method()->max_locals(), "sanity");
   175   assert(max_stack  >= method()->max_stack(),  "sanity");
   176   assert((int)jvms()->endoff() == TypeFunc::Parms + max_locals + max_stack, "sanity");
   177   assert((int)jvms()->endoff() == (int)map()->req(), "sanity");
   179   // Find the start block.
   180   Block* osr_block = start_block();
   181   assert(osr_block->start() == osr_bci(), "sanity");
   183   // Set initial BCI.
   184   set_parse_bci(osr_block->start());
   186   // Set initial stack depth.
   187   set_sp(osr_block->start_sp());
   189   // Check bailouts.  We currently do not perform on stack replacement
   190   // of loops in catch blocks or loops which branch with a non-empty stack.
   191   if (sp() != 0) {
   192     C->record_method_not_compilable("OSR starts with non-empty stack");
   193     return;
   194   }
   195   // Do not OSR inside finally clauses:
   196   if (osr_block->has_trap_at(osr_block->start())) {
   197     C->record_method_not_compilable("OSR starts with an immediate trap");
   198     return;
   199   }
   201   // Commute monitors from interpreter frame to compiler frame.
   202   assert(jvms()->monitor_depth() == 0, "should be no active locks at beginning of osr");
   203   int mcnt = osr_block->flow()->monitor_count();
   204   Node *monitors_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals+mcnt*2-1)*wordSize);
   205   for (index = 0; index < mcnt; index++) {
   206     // Make a BoxLockNode for the monitor.
   207     Node *box = _gvn.transform(new (C, 1) BoxLockNode(next_monitor()));
   210     // Displaced headers and locked objects are interleaved in the
   211     // temp OSR buffer.  We only copy the locked objects out here.
   212     // Fetch the locked object from the OSR temp buffer and copy to our fastlock node.
   213     Node *lock_object = fetch_interpreter_state(index*2, T_OBJECT, monitors_addr, osr_buf);
   214     // Try and copy the displaced header to the BoxNode
   215     Node *displaced_hdr = fetch_interpreter_state((index*2) + 1, T_ADDRESS, monitors_addr, osr_buf);
   218     store_to_memory(control(), box, displaced_hdr, T_ADDRESS, Compile::AliasIdxRaw);
   220     // Build a bogus FastLockNode (no code will be generated) and push the
   221     // monitor into our debug info.
   222     const FastLockNode *flock = _gvn.transform(new (C, 3) FastLockNode( 0, lock_object, box ))->as_FastLock();
   223     map()->push_monitor(flock);
   225     // If the lock is our method synchronization lock, tuck it away in
   226     // _sync_lock for return and rethrow exit paths.
   227     if (index == 0 && method()->is_synchronized()) {
   228       _synch_lock = flock;
   229     }
   230   }
   232   // Use the raw liveness computation to make sure that unexpected
   233   // values don't propagate into the OSR frame.
   234   MethodLivenessResult live_locals = method()->raw_liveness_at_bci(osr_bci());
   235   if (!live_locals.is_valid()) {
   236     // Degenerate or breakpointed method.
   237     C->record_method_not_compilable("OSR in empty or breakpointed method");
   238     return;
   239   }
   241   // Extract the needed locals from the interpreter frame.
   242   Node *locals_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals-1)*wordSize);
   244   // find all the locals that the interpreter thinks contain live oops
   245   const BitMap live_oops = method()->live_local_oops_at_bci(osr_bci());
   246   for (index = 0; index < max_locals; index++) {
   248     if (!live_locals.at(index)) {
   249       continue;
   250     }
   252     const Type *type = osr_block->local_type_at(index);
   254     if (type->isa_oopptr() != NULL) {
   256       // 6403625: Verify that the interpreter oopMap thinks that the oop is live
   257       // else we might load a stale oop if the MethodLiveness disagrees with the
   258       // result of the interpreter. If the interpreter says it is dead we agree
   259       // by making the value go to top.
   260       //
   262       if (!live_oops.at(index)) {
   263         if (C->log() != NULL) {
   264           C->log()->elem("OSR_mismatch local_index='%d'",index);
   265         }
   266         set_local(index, null());
   267         // and ignore it for the loads
   268         continue;
   269       }
   270     }
   272     // Filter out TOP, HALF, and BOTTOM.  (Cf. ensure_phi.)
   273     if (type == Type::TOP || type == Type::HALF) {
   274       continue;
   275     }
   276     // If the type falls to bottom, then this must be a local that
   277     // is mixing ints and oops or some such.  Forcing it to top
   278     // makes it go dead.
   279     if (type == Type::BOTTOM) {
   280       continue;
   281     }
   282     // Construct code to access the appropriate local.
   283     Node *value = fetch_interpreter_state(index, type->basic_type(), locals_addr, osr_buf);
   284     set_local(index, value);
   285   }
   287   // Extract the needed stack entries from the interpreter frame.
   288   for (index = 0; index < sp(); index++) {
   289     const Type *type = osr_block->stack_type_at(index);
   290     if (type != Type::TOP) {
   291       // Currently the compiler bails out when attempting to on stack replace
   292       // at a bci with a non-empty stack.  We should not reach here.
   293       ShouldNotReachHere();
   294     }
   295   }
   297   // End the OSR migration
   298   make_runtime_call(RC_LEAF, OptoRuntime::osr_end_Type(),
   299                     CAST_FROM_FN_PTR(address, SharedRuntime::OSR_migration_end),
   300                     "OSR_migration_end", TypeRawPtr::BOTTOM,
   301                     osr_buf);
   303   // Now that the interpreter state is loaded, make sure it will match
   304   // at execution time what the compiler is expecting now:
   305   SafePointNode* bad_type_exit = clone_map();
   306   bad_type_exit->set_control(new (C, 1) RegionNode(1));
   308   for (index = 0; index < max_locals; index++) {
   309     if (stopped())  break;
   310     Node* l = local(index);
   311     if (l->is_top())  continue;  // nothing here
   312     const Type *type = osr_block->local_type_at(index);
   313     if (type->isa_oopptr() != NULL) {
   314       if (!live_oops.at(index)) {
   315         // skip type check for dead oops
   316         continue;
   317       }
   318     }
   319     set_local(index, check_interpreter_type(l, type, bad_type_exit));
   320   }
   322   for (index = 0; index < sp(); index++) {
   323     if (stopped())  break;
   324     Node* l = stack(index);
   325     if (l->is_top())  continue;  // nothing here
   326     const Type *type = osr_block->stack_type_at(index);
   327     set_stack(index, check_interpreter_type(l, type, bad_type_exit));
   328   }
   330   if (bad_type_exit->control()->req() > 1) {
   331     // Build an uncommon trap here, if any inputs can be unexpected.
   332     bad_type_exit->set_control(_gvn.transform( bad_type_exit->control() ));
   333     record_for_igvn(bad_type_exit->control());
   334     SafePointNode* types_are_good = map();
   335     set_map(bad_type_exit);
   336     // The unexpected type happens because a new edge is active
   337     // in the CFG, which typeflow had previously ignored.
   338     // E.g., Object x = coldAtFirst() && notReached()? "str": new Integer(123).
   339     // This x will be typed as Integer if notReached is not yet linked.
   340     uncommon_trap(Deoptimization::Reason_unreached,
   341                   Deoptimization::Action_reinterpret);
   342     set_map(types_are_good);
   343   }
   344 }
   346 //------------------------------Parse------------------------------------------
   347 // Main parser constructor.
   348 Parse::Parse(JVMState* caller, ciMethod* parse_method, float expected_uses)
   349   : _exits(caller)
   350 {
   351   // Init some variables
   352   _caller = caller;
   353   _method = parse_method;
   354   _expected_uses = expected_uses;
   355   _depth = 1 + (caller->has_method() ? caller->depth() : 0);
   356   _wrote_final = false;
   357   _entry_bci = InvocationEntryBci;
   358   _tf = NULL;
   359   _block = NULL;
   360   debug_only(_block_count = -1);
   361   debug_only(_blocks = (Block*)-1);
   362 #ifndef PRODUCT
   363   if (PrintCompilation || PrintOpto) {
   364     // Make sure I have an inline tree, so I can print messages about it.
   365     JVMState* ilt_caller = is_osr_parse() ? caller->caller() : caller;
   366     InlineTree::find_subtree_from_root(C->ilt(), ilt_caller, parse_method, true);
   367   }
   368   _max_switch_depth = 0;
   369   _est_switch_depth = 0;
   370 #endif
   372   _tf = TypeFunc::make(method());
   373   _iter.reset_to_method(method());
   374   _flow = method()->get_flow_analysis();
   375   if (_flow->failing()) {
   376     C->record_method_not_compilable_all_tiers(_flow->failure_reason());
   377   }
   379 #ifndef PRODUCT
   380   if (_flow->has_irreducible_entry()) {
   381     C->set_parsed_irreducible_loop(true);
   382   }
   383 #endif
   385   if (_expected_uses <= 0) {
   386     _prof_factor = 1;
   387   } else {
   388     float prof_total = parse_method->interpreter_invocation_count();
   389     if (prof_total <= _expected_uses) {
   390       _prof_factor = 1;
   391     } else {
   392       _prof_factor = _expected_uses / prof_total;
   393     }
   394   }
   396   CompileLog* log = C->log();
   397   if (log != NULL) {
   398     log->begin_head("parse method='%d' uses='%g'",
   399                     log->identify(parse_method), expected_uses);
   400     if (depth() == 1 && C->is_osr_compilation()) {
   401       log->print(" osr_bci='%d'", C->entry_bci());
   402     }
   403     log->stamp();
   404     log->end_head();
   405   }
   407   // Accumulate deoptimization counts.
   408   // (The range_check and store_check counts are checked elsewhere.)
   409   ciMethodData* md = method()->method_data();
   410   for (uint reason = 0; reason < md->trap_reason_limit(); reason++) {
   411     uint md_count = md->trap_count(reason);
   412     if (md_count != 0) {
   413       if (md_count == md->trap_count_limit())
   414         md_count += md->overflow_trap_count();
   415       uint total_count = C->trap_count(reason);
   416       uint old_count   = total_count;
   417       total_count += md_count;
   418       // Saturate the add if it overflows.
   419       if (total_count < old_count || total_count < md_count)
   420         total_count = (uint)-1;
   421       C->set_trap_count(reason, total_count);
   422       if (log != NULL)
   423         log->elem("observe trap='%s' count='%d' total='%d'",
   424                   Deoptimization::trap_reason_name(reason),
   425                   md_count, total_count);
   426     }
   427   }
   428   // Accumulate total sum of decompilations, also.
   429   C->set_decompile_count(C->decompile_count() + md->decompile_count());
   431   _count_invocations = C->do_count_invocations();
   432   _method_data_update = C->do_method_data_update();
   434   if (log != NULL && method()->has_exception_handlers()) {
   435     log->elem("observe that='has_exception_handlers'");
   436   }
   438   assert(method()->can_be_compiled(),       "Can not parse this method, cutout earlier");
   439   assert(method()->has_balanced_monitors(), "Can not parse unbalanced monitors, cutout earlier");
   441   // Always register dependence if JVMTI is enabled, because
   442   // either breakpoint setting or hotswapping of methods may
   443   // cause deoptimization.
   444   if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
   445     C->dependencies()->assert_evol_method(method());
   446   }
   448   methods_seen++;
   450   // Do some special top-level things.
   451   if (depth() == 1 && C->is_osr_compilation()) {
   452     _entry_bci = C->entry_bci();
   453     _flow = method()->get_osr_flow_analysis(osr_bci());
   454     if (_flow->failing()) {
   455       C->record_method_not_compilable(_flow->failure_reason());
   456 #ifndef PRODUCT
   457       if (PrintOpto && (Verbose || WizardMode)) {
   458         tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
   459         if (Verbose) {
   460           method()->print_oop();
   461           method()->print_codes();
   462           _flow->print();
   463         }
   464       }
   465 #endif
   466     }
   467     _tf = C->tf();     // the OSR entry type is different
   468   }
   470 #ifdef ASSERT
   471   if (depth() == 1) {
   472     assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");
   473     if (C->tf() != tf()) {
   474       MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
   475       assert(C->env()->system_dictionary_modification_counter_changed(),
   476              "Must invalidate if TypeFuncs differ");
   477     }
   478   } else {
   479     assert(!this->is_osr_parse(), "no recursive OSR");
   480   }
   481 #endif
   483   methods_parsed++;
   484 #ifndef PRODUCT
   485   // add method size here to guarantee that inlined methods are added too
   486   if (TimeCompiler)
   487     _total_bytes_compiled += method()->code_size();
   489   show_parse_info();
   490 #endif
   492   if (failing()) {
   493     if (log)  log->done("parse");
   494     return;
   495   }
   497   gvn().set_type(root(), root()->bottom_type());
   498   gvn().transform(top());
   500   // Import the results of the ciTypeFlow.
   501   init_blocks();
   503   // Merge point for all normal exits
   504   build_exits();
   506   // Setup the initial JVM state map.
   507   SafePointNode* entry_map = create_entry_map();
   509   // Check for bailouts during map initialization
   510   if (failing() || entry_map == NULL) {
   511     if (log)  log->done("parse");
   512     return;
   513   }
   515   Node_Notes* caller_nn = C->default_node_notes();
   516   // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
   517   if (DebugInlinedCalls || depth() == 1) {
   518     C->set_default_node_notes(make_node_notes(caller_nn));
   519   }
   521   if (is_osr_parse()) {
   522     Node* osr_buf = entry_map->in(TypeFunc::Parms+0);
   523     entry_map->set_req(TypeFunc::Parms+0, top());
   524     set_map(entry_map);
   525     load_interpreter_state(osr_buf);
   526   } else {
   527     set_map(entry_map);
   528     do_method_entry();
   529   }
   531   // Check for bailouts during method entry.
   532   if (failing()) {
   533     if (log)  log->done("parse");
   534     C->set_default_node_notes(caller_nn);
   535     return;
   536   }
   538   entry_map = map();  // capture any changes performed by method setup code
   539   assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");
   541   // We begin parsing as if we have just encountered a jump to the
   542   // method entry.
   543   Block* entry_block = start_block();
   544   assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
   545   set_map_clone(entry_map);
   546   merge_common(entry_block, entry_block->next_path_num());
   548 #ifndef PRODUCT
   549   BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
   550   set_parse_histogram( parse_histogram_obj );
   551 #endif
   553   // Parse all the basic blocks.
   554   do_all_blocks();
   556   C->set_default_node_notes(caller_nn);
   558   // Check for bailouts during conversion to graph
   559   if (failing()) {
   560     if (log)  log->done("parse");
   561     return;
   562   }
   564   // Fix up all exiting control flow.
   565   set_map(entry_map);
   566   do_exits();
   568   if (log)  log->done("parse nodes='%d' memory='%d'",
   569                       C->unique(), C->node_arena()->used());
   570 }
   572 //---------------------------do_all_blocks-------------------------------------
   573 void Parse::do_all_blocks() {
   574   bool has_irreducible = flow()->has_irreducible_entry();
   576   // Walk over all blocks in Reverse Post-Order.
   577   while (true) {
   578     bool progress = false;
   579     for (int rpo = 0; rpo < block_count(); rpo++) {
   580       Block* block = rpo_at(rpo);
   582       if (block->is_parsed()) continue;
   584       if (!block->is_merged()) {
   585         // Dead block, no state reaches this block
   586         continue;
   587       }
   589       // Prepare to parse this block.
   590       load_state_from(block);
   592       if (stopped()) {
   593         // Block is dead.
   594         continue;
   595       }
   597       blocks_parsed++;
   599       progress = true;
   600       if (block->is_loop_head() || block->is_handler() || has_irreducible && !block->is_ready()) {
   601         // Not all preds have been parsed.  We must build phis everywhere.
   602         // (Note that dead locals do not get phis built, ever.)
   603         ensure_phis_everywhere();
   605         // Leave behind an undisturbed copy of the map, for future merges.
   606         set_map(clone_map());
   607       }
   609       if (control()->is_Region() && !block->is_loop_head() && !has_irreducible && !block->is_handler()) {
   610         // In the absence of irreducible loops, the Region and Phis
   611         // associated with a merge that doesn't involve a backedge can
   612         // be simplified now since the RPO parsing order guarantees
   613         // that any path which was supposed to reach here has already
   614         // been parsed or must be dead.
   615         Node* c = control();
   616         Node* result = _gvn.transform_no_reclaim(control());
   617         if (c != result && TraceOptoParse) {
   618           tty->print_cr("Block #%d replace %d with %d", block->rpo(), c->_idx, result->_idx);
   619         }
   620         if (result != top()) {
   621           record_for_igvn(result);
   622         }
   623       }
   625       // Parse the block.
   626       do_one_block();
   628       // Check for bailouts.
   629       if (failing())  return;
   630     }
   632     // with irreducible loops multiple passes might be necessary to parse everything
   633     if (!has_irreducible || !progress) {
   634       break;
   635     }
   636   }
   638   blocks_seen += block_count();
   640 #ifndef PRODUCT
   641   // Make sure there are no half-processed blocks remaining.
   642   // Every remaining unprocessed block is dead and may be ignored now.
   643   for (int rpo = 0; rpo < block_count(); rpo++) {
   644     Block* block = rpo_at(rpo);
   645     if (!block->is_parsed()) {
   646       if (TraceOptoParse) {
   647         tty->print_cr("Skipped dead block %d at bci:%d", rpo, block->start());
   648       }
   649       assert(!block->is_merged(), "no half-processed blocks");
   650     }
   651   }
   652 #endif
   653 }
   655 //-------------------------------build_exits----------------------------------
   656 // Build normal and exceptional exit merge points.
   657 void Parse::build_exits() {
   658   // make a clone of caller to prevent sharing of side-effects
   659   _exits.set_map(_exits.clone_map());
   660   _exits.clean_stack(_exits.sp());
   661   _exits.sync_jvms();
   663   RegionNode* region = new (C, 1) RegionNode(1);
   664   record_for_igvn(region);
   665   gvn().set_type_bottom(region);
   666   _exits.set_control(region);
   668   // Note:  iophi and memphi are not transformed until do_exits.
   669   Node* iophi  = new (C, region->req()) PhiNode(region, Type::ABIO);
   670   Node* memphi = new (C, region->req()) PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
   671   _exits.set_i_o(iophi);
   672   _exits.set_all_memory(memphi);
   674   // Add a return value to the exit state.  (Do not push it yet.)
   675   if (tf()->range()->cnt() > TypeFunc::Parms) {
   676     const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
   677     // Don't "bind" an unloaded return klass to the ret_phi. If the klass
   678     // becomes loaded during the subsequent parsing, the loaded and unloaded
   679     // types will not join when we transform and push in do_exits().
   680     const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
   681     if (ret_oop_type && !ret_oop_type->klass()->is_loaded()) {
   682       ret_type = TypeOopPtr::BOTTOM;
   683     }
   684     int         ret_size = type2size[ret_type->basic_type()];
   685     Node*       ret_phi  = new (C, region->req()) PhiNode(region, ret_type);
   686     _exits.ensure_stack(ret_size);
   687     assert((int)(tf()->range()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
   688     assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
   689     _exits.set_argument(0, ret_phi);  // here is where the parser finds it
   690     // Note:  ret_phi is not yet pushed, until do_exits.
   691   }
   692 }
   695 //----------------------------build_start_state-------------------------------
   696 // Construct a state which contains only the incoming arguments from an
   697 // unknown caller.  The method & bci will be NULL & InvocationEntryBci.
   698 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
   699   int        arg_size = tf->domain()->cnt();
   700   int        max_size = MAX2(arg_size, (int)tf->range()->cnt());
   701   JVMState*  jvms     = new (this) JVMState(max_size - TypeFunc::Parms);
   702   SafePointNode* map  = new (this, max_size) SafePointNode(max_size, NULL);
   703   record_for_igvn(map);
   704   assert(arg_size == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
   705   Node_Notes* old_nn = default_node_notes();
   706   if (old_nn != NULL && has_method()) {
   707     Node_Notes* entry_nn = old_nn->clone(this);
   708     JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
   709     entry_jvms->set_offsets(0);
   710     entry_jvms->set_bci(entry_bci());
   711     entry_nn->set_jvms(entry_jvms);
   712     set_default_node_notes(entry_nn);
   713   }
   714   uint i;
   715   for (i = 0; i < (uint)arg_size; i++) {
   716     Node* parm = initial_gvn()->transform(new (this, 1) ParmNode(start, i));
   717     map->init_req(i, parm);
   718     // Record all these guys for later GVN.
   719     record_for_igvn(parm);
   720   }
   721   for (; i < map->req(); i++) {
   722     map->init_req(i, top());
   723   }
   724   assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
   725   set_default_node_notes(old_nn);
   726   map->set_jvms(jvms);
   727   jvms->set_map(map);
   728   return jvms;
   729 }
   731 //-----------------------------make_node_notes---------------------------------
   732 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
   733   if (caller_nn == NULL)  return NULL;
   734   Node_Notes* nn = caller_nn->clone(C);
   735   JVMState* caller_jvms = nn->jvms();
   736   JVMState* jvms = new (C) JVMState(method(), caller_jvms);
   737   jvms->set_offsets(0);
   738   jvms->set_bci(_entry_bci);
   739   nn->set_jvms(jvms);
   740   return nn;
   741 }
   744 //--------------------------return_values--------------------------------------
   745 void Compile::return_values(JVMState* jvms) {
   746   GraphKit kit(jvms);
   747   Node* ret = new (this, TypeFunc::Parms) ReturnNode(TypeFunc::Parms,
   748                              kit.control(),
   749                              kit.i_o(),
   750                              kit.reset_memory(),
   751                              kit.frameptr(),
   752                              kit.returnadr());
   753   // Add zero or 1 return values
   754   int ret_size = tf()->range()->cnt() - TypeFunc::Parms;
   755   if (ret_size > 0) {
   756     kit.inc_sp(-ret_size);  // pop the return value(s)
   757     kit.sync_jvms();
   758     ret->add_req(kit.argument(0));
   759     // Note:  The second dummy edge is not needed by a ReturnNode.
   760   }
   761   // bind it to root
   762   root()->add_req(ret);
   763   record_for_igvn(ret);
   764   initial_gvn()->transform_no_reclaim(ret);
   765 }
   767 //------------------------rethrow_exceptions-----------------------------------
   768 // Bind all exception states in the list into a single RethrowNode.
   769 void Compile::rethrow_exceptions(JVMState* jvms) {
   770   GraphKit kit(jvms);
   771   if (!kit.has_exceptions())  return;  // nothing to generate
   772   // Load my combined exception state into the kit, with all phis transformed:
   773   SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
   774   Node* ex_oop = kit.use_exception_state(ex_map);
   775   RethrowNode* exit = new (this, TypeFunc::Parms + 1) RethrowNode(kit.control(),
   776                                       kit.i_o(), kit.reset_memory(),
   777                                       kit.frameptr(), kit.returnadr(),
   778                                       // like a return but with exception input
   779                                       ex_oop);
   780   // bind to root
   781   root()->add_req(exit);
   782   record_for_igvn(exit);
   783   initial_gvn()->transform_no_reclaim(exit);
   784 }
   786 bool Parse::can_rerun_bytecode() {
   787   switch (bc()) {
   788   case Bytecodes::_ldc:
   789   case Bytecodes::_ldc_w:
   790   case Bytecodes::_ldc2_w:
   791   case Bytecodes::_getfield:
   792   case Bytecodes::_putfield:
   793   case Bytecodes::_getstatic:
   794   case Bytecodes::_putstatic:
   795   case Bytecodes::_arraylength:
   796   case Bytecodes::_baload:
   797   case Bytecodes::_caload:
   798   case Bytecodes::_iaload:
   799   case Bytecodes::_saload:
   800   case Bytecodes::_faload:
   801   case Bytecodes::_aaload:
   802   case Bytecodes::_laload:
   803   case Bytecodes::_daload:
   804   case Bytecodes::_bastore:
   805   case Bytecodes::_castore:
   806   case Bytecodes::_iastore:
   807   case Bytecodes::_sastore:
   808   case Bytecodes::_fastore:
   809   case Bytecodes::_aastore:
   810   case Bytecodes::_lastore:
   811   case Bytecodes::_dastore:
   812   case Bytecodes::_irem:
   813   case Bytecodes::_idiv:
   814   case Bytecodes::_lrem:
   815   case Bytecodes::_ldiv:
   816   case Bytecodes::_frem:
   817   case Bytecodes::_fdiv:
   818   case Bytecodes::_drem:
   819   case Bytecodes::_ddiv:
   820   case Bytecodes::_checkcast:
   821   case Bytecodes::_instanceof:
   822   case Bytecodes::_athrow:
   823   case Bytecodes::_anewarray:
   824   case Bytecodes::_newarray:
   825   case Bytecodes::_multianewarray:
   826   case Bytecodes::_new:
   827   case Bytecodes::_monitorenter:  // can re-run initial null check, only
   828   case Bytecodes::_return:
   829     return true;
   830     break;
   832   case Bytecodes::_invokestatic:
   833   case Bytecodes::_invokedynamic:
   834   case Bytecodes::_invokespecial:
   835   case Bytecodes::_invokevirtual:
   836   case Bytecodes::_invokeinterface:
   837     return false;
   838     break;
   840   default:
   841     assert(false, "unexpected bytecode produced an exception");
   842     return true;
   843   }
   844 }
   846 //---------------------------do_exceptions-------------------------------------
   847 // Process exceptions arising from the current bytecode.
   848 // Send caught exceptions to the proper handler within this method.
   849 // Unhandled exceptions feed into _exit.
   850 void Parse::do_exceptions() {
   851   if (!has_exceptions())  return;
   853   if (failing()) {
   854     // Pop them all off and throw them away.
   855     while (pop_exception_state() != NULL) ;
   856     return;
   857   }
   859   // Make sure we can classify this bytecode if we need to.
   860   debug_only(can_rerun_bytecode());
   862   PreserveJVMState pjvms(this, false);
   864   SafePointNode* ex_map;
   865   while ((ex_map = pop_exception_state()) != NULL) {
   866     if (!method()->has_exception_handlers()) {
   867       // Common case:  Transfer control outward.
   868       // Doing it this early allows the exceptions to common up
   869       // even between adjacent method calls.
   870       throw_to_exit(ex_map);
   871     } else {
   872       // Have to look at the exception first.
   873       assert(stopped(), "catch_inline_exceptions trashes the map");
   874       catch_inline_exceptions(ex_map);
   875       stop_and_kill_map();      // we used up this exception state; kill it
   876     }
   877   }
   879   // We now return to our regularly scheduled program:
   880 }
   882 //---------------------------throw_to_exit-------------------------------------
   883 // Merge the given map into an exception exit from this method.
   884 // The exception exit will handle any unlocking of receiver.
   885 // The ex_oop must be saved within the ex_map, unlike merge_exception.
   886 void Parse::throw_to_exit(SafePointNode* ex_map) {
   887   // Pop the JVMS to (a copy of) the caller.
   888   GraphKit caller;
   889   caller.set_map_clone(_caller->map());
   890   caller.set_bci(_caller->bci());
   891   caller.set_sp(_caller->sp());
   892   // Copy out the standard machine state:
   893   for (uint i = 0; i < TypeFunc::Parms; i++) {
   894     caller.map()->set_req(i, ex_map->in(i));
   895   }
   896   // ...and the exception:
   897   Node*          ex_oop        = saved_ex_oop(ex_map);
   898   SafePointNode* caller_ex_map = caller.make_exception_state(ex_oop);
   899   // Finally, collect the new exception state in my exits:
   900   _exits.add_exception_state(caller_ex_map);
   901 }
   903 //------------------------------do_exits---------------------------------------
   904 void Parse::do_exits() {
   905   set_parse_bci(InvocationEntryBci);
   907   // Now peephole on the return bits
   908   Node* region = _exits.control();
   909   _exits.set_control(gvn().transform(region));
   911   Node* iophi = _exits.i_o();
   912   _exits.set_i_o(gvn().transform(iophi));
   914   if (wrote_final()) {
   915     // This method (which must be a constructor by the rules of Java)
   916     // wrote a final.  The effects of all initializations must be
   917     // committed to memory before any code after the constructor
   918     // publishes the reference to the newly constructor object.
   919     // Rather than wait for the publication, we simply block the
   920     // writes here.  Rather than put a barrier on only those writes
   921     // which are required to complete, we force all writes to complete.
   922     //
   923     // "All bets are off" unless the first publication occurs after a
   924     // normal return from the constructor.  We do not attempt to detect
   925     // such unusual early publications.  But no barrier is needed on
   926     // exceptional returns, since they cannot publish normally.
   927     //
   928     _exits.insert_mem_bar(Op_MemBarRelease);
   929 #ifndef PRODUCT
   930     if (PrintOpto && (Verbose || WizardMode)) {
   931       method()->print_name();
   932       tty->print_cr(" writes finals and needs a memory barrier");
   933     }
   934 #endif
   935   }
   937   for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
   938     // transform each slice of the original memphi:
   939     mms.set_memory(_gvn.transform(mms.memory()));
   940   }
   942   if (tf()->range()->cnt() > TypeFunc::Parms) {
   943     const Type* ret_type = tf()->range()->field_at(TypeFunc::Parms);
   944     Node*       ret_phi  = _gvn.transform( _exits.argument(0) );
   945     assert(_exits.control()->is_top() || !_gvn.type(ret_phi)->empty(), "return value must be well defined");
   946     _exits.push_node(ret_type->basic_type(), ret_phi);
   947   }
   949   // Note:  Logic for creating and optimizing the ReturnNode is in Compile.
   951   // Unlock along the exceptional paths.
   952   // This is done late so that we can common up equivalent exceptions
   953   // (e.g., null checks) arising from multiple points within this method.
   954   // See GraphKit::add_exception_state, which performs the commoning.
   955   bool do_synch = method()->is_synchronized() && GenerateSynchronizationCode;
   957   // record exit from a method if compiled while Dtrace is turned on.
   958   if (do_synch || C->env()->dtrace_method_probes()) {
   959     // First move the exception list out of _exits:
   960     GraphKit kit(_exits.transfer_exceptions_into_jvms());
   961     SafePointNode* normal_map = kit.map();  // keep this guy safe
   962     // Now re-collect the exceptions into _exits:
   963     SafePointNode* ex_map;
   964     while ((ex_map = kit.pop_exception_state()) != NULL) {
   965       Node* ex_oop = kit.use_exception_state(ex_map);
   966       // Force the exiting JVM state to have this method at InvocationEntryBci.
   967       // The exiting JVM state is otherwise a copy of the calling JVMS.
   968       JVMState* caller = kit.jvms();
   969       JVMState* ex_jvms = caller->clone_shallow(C);
   970       ex_jvms->set_map(kit.clone_map());
   971       ex_jvms->map()->set_jvms(ex_jvms);
   972       ex_jvms->set_bci(   InvocationEntryBci);
   973       kit.set_jvms(ex_jvms);
   974       if (do_synch) {
   975         // Add on the synchronized-method box/object combo
   976         kit.map()->push_monitor(_synch_lock);
   977         // Unlock!
   978         kit.shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
   979       }
   980       if (C->env()->dtrace_method_probes()) {
   981         kit.make_dtrace_method_exit(method());
   982       }
   983       // Done with exception-path processing.
   984       ex_map = kit.make_exception_state(ex_oop);
   985       assert(ex_jvms->same_calls_as(ex_map->jvms()), "sanity");
   986       // Pop the last vestige of this method:
   987       ex_map->set_jvms(caller->clone_shallow(C));
   988       ex_map->jvms()->set_map(ex_map);
   989       _exits.push_exception_state(ex_map);
   990     }
   991     assert(_exits.map() == normal_map, "keep the same return state");
   992   }
   994   {
   995     // Capture very early exceptions (receiver null checks) from caller JVMS
   996     GraphKit caller(_caller);
   997     SafePointNode* ex_map;
   998     while ((ex_map = caller.pop_exception_state()) != NULL) {
   999       _exits.add_exception_state(ex_map);
  1004 //-----------------------------create_entry_map-------------------------------
  1005 // Initialize our parser map to contain the types at method entry.
  1006 // For OSR, the map contains a single RawPtr parameter.
  1007 // Initial monitor locking for sync. methods is performed by do_method_entry.
  1008 SafePointNode* Parse::create_entry_map() {
  1009   // Check for really stupid bail-out cases.
  1010   uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
  1011   if (len >= 32760) {
  1012     C->record_method_not_compilable_all_tiers("too many local variables");
  1013     return NULL;
  1016   // If this is an inlined method, we may have to do a receiver null check.
  1017   if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
  1018     GraphKit kit(_caller);
  1019     kit.null_check_receiver(method());
  1020     _caller = kit.transfer_exceptions_into_jvms();
  1021     if (kit.stopped()) {
  1022       _exits.add_exception_states_from(_caller);
  1023       _exits.set_jvms(_caller);
  1024       return NULL;
  1028   assert(method() != NULL, "parser must have a method");
  1030   // Create an initial safepoint to hold JVM state during parsing
  1031   JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : NULL);
  1032   set_map(new (C, len) SafePointNode(len, jvms));
  1033   jvms->set_map(map());
  1034   record_for_igvn(map());
  1035   assert(jvms->endoff() == len, "correct jvms sizing");
  1037   SafePointNode* inmap = _caller->map();
  1038   assert(inmap != NULL, "must have inmap");
  1040   uint i;
  1042   // Pass thru the predefined input parameters.
  1043   for (i = 0; i < TypeFunc::Parms; i++) {
  1044     map()->init_req(i, inmap->in(i));
  1047   if (depth() == 1) {
  1048     assert(map()->memory()->Opcode() == Op_Parm, "");
  1049     // Insert the memory aliasing node
  1050     set_all_memory(reset_memory());
  1052   assert(merged_memory(), "");
  1054   // Now add the locals which are initially bound to arguments:
  1055   uint arg_size = tf()->domain()->cnt();
  1056   ensure_stack(arg_size - TypeFunc::Parms);  // OSR methods have funny args
  1057   for (i = TypeFunc::Parms; i < arg_size; i++) {
  1058     map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
  1061   // Clear out the rest of the map (locals and stack)
  1062   for (i = arg_size; i < len; i++) {
  1063     map()->init_req(i, top());
  1066   SafePointNode* entry_map = stop();
  1067   return entry_map;
  1070 //-----------------------------do_method_entry--------------------------------
  1071 // Emit any code needed in the pseudo-block before BCI zero.
  1072 // The main thing to do is lock the receiver of a synchronized method.
  1073 void Parse::do_method_entry() {
  1074   set_parse_bci(InvocationEntryBci); // Pseudo-BCP
  1075   set_sp(0);                      // Java Stack Pointer
  1077   NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
  1079   if (C->env()->dtrace_method_probes()) {
  1080     make_dtrace_method_entry(method());
  1083   // If the method is synchronized, we need to construct a lock node, attach
  1084   // it to the Start node, and pin it there.
  1085   if (method()->is_synchronized()) {
  1086     // Insert a FastLockNode right after the Start which takes as arguments
  1087     // the current thread pointer, the "this" pointer & the address of the
  1088     // stack slot pair used for the lock.  The "this" pointer is a projection
  1089     // off the start node, but the locking spot has to be constructed by
  1090     // creating a ConLNode of 0, and boxing it with a BoxLockNode.  The BoxLockNode
  1091     // becomes the second argument to the FastLockNode call.  The
  1092     // FastLockNode becomes the new control parent to pin it to the start.
  1094     // Setup Object Pointer
  1095     Node *lock_obj = NULL;
  1096     if(method()->is_static()) {
  1097       ciInstance* mirror = _method->holder()->java_mirror();
  1098       const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
  1099       lock_obj = makecon(t_lock);
  1100     } else {                  // Else pass the "this" pointer,
  1101       lock_obj = local(0);    // which is Parm0 from StartNode
  1103     // Clear out dead values from the debug info.
  1104     kill_dead_locals();
  1105     // Build the FastLockNode
  1106     _synch_lock = shared_lock(lock_obj);
  1109   if (depth() == 1) {
  1110     increment_and_test_invocation_counter(Tier2CompileThreshold);
  1114 //------------------------------init_blocks------------------------------------
  1115 // Initialize our parser map to contain the types/monitors at method entry.
  1116 void Parse::init_blocks() {
  1117   // Create the blocks.
  1118   _block_count = flow()->block_count();
  1119   _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);
  1120   Copy::zero_to_bytes(_blocks, sizeof(Block)*_block_count);
  1122   int rpo;
  1124   // Initialize the structs.
  1125   for (rpo = 0; rpo < block_count(); rpo++) {
  1126     Block* block = rpo_at(rpo);
  1127     block->init_node(this, rpo);
  1130   // Collect predecessor and successor information.
  1131   for (rpo = 0; rpo < block_count(); rpo++) {
  1132     Block* block = rpo_at(rpo);
  1133     block->init_graph(this);
  1137 //-------------------------------init_node-------------------------------------
  1138 void Parse::Block::init_node(Parse* outer, int rpo) {
  1139   _flow = outer->flow()->rpo_at(rpo);
  1140   _pred_count = 0;
  1141   _preds_parsed = 0;
  1142   _count = 0;
  1143   assert(pred_count() == 0 && preds_parsed() == 0, "sanity");
  1144   assert(!(is_merged() || is_parsed() || is_handler()), "sanity");
  1145   assert(_live_locals.size() == 0, "sanity");
  1147   // entry point has additional predecessor
  1148   if (flow()->is_start())  _pred_count++;
  1149   assert(flow()->is_start() == (this == outer->start_block()), "");
  1152 //-------------------------------init_graph------------------------------------
  1153 void Parse::Block::init_graph(Parse* outer) {
  1154   // Create the successor list for this parser block.
  1155   GrowableArray<ciTypeFlow::Block*>* tfs = flow()->successors();
  1156   GrowableArray<ciTypeFlow::Block*>* tfe = flow()->exceptions();
  1157   int ns = tfs->length();
  1158   int ne = tfe->length();
  1159   _num_successors = ns;
  1160   _all_successors = ns+ne;
  1161   _successors = (ns+ne == 0) ? NULL : NEW_RESOURCE_ARRAY(Block*, ns+ne);
  1162   int p = 0;
  1163   for (int i = 0; i < ns+ne; i++) {
  1164     ciTypeFlow::Block* tf2 = (i < ns) ? tfs->at(i) : tfe->at(i-ns);
  1165     Block* block2 = outer->rpo_at(tf2->rpo());
  1166     _successors[i] = block2;
  1168     // Accumulate pred info for the other block, too.
  1169     if (i < ns) {
  1170       block2->_pred_count++;
  1171     } else {
  1172       block2->_is_handler = true;
  1175     #ifdef ASSERT
  1176     // A block's successors must be distinguishable by BCI.
  1177     // That is, no bytecode is allowed to branch to two different
  1178     // clones of the same code location.
  1179     for (int j = 0; j < i; j++) {
  1180       Block* block1 = _successors[j];
  1181       if (block1 == block2)  continue;  // duplicates are OK
  1182       assert(block1->start() != block2->start(), "successors have unique bcis");
  1184     #endif
  1187   // Note: We never call next_path_num along exception paths, so they
  1188   // never get processed as "ready".  Also, the input phis of exception
  1189   // handlers get specially processed, so that
  1192 //---------------------------successor_for_bci---------------------------------
  1193 Parse::Block* Parse::Block::successor_for_bci(int bci) {
  1194   for (int i = 0; i < all_successors(); i++) {
  1195     Block* block2 = successor_at(i);
  1196     if (block2->start() == bci)  return block2;
  1198   // We can actually reach here if ciTypeFlow traps out a block
  1199   // due to an unloaded class, and concurrently with compilation the
  1200   // class is then loaded, so that a later phase of the parser is
  1201   // able to see more of the bytecode CFG.  Or, the flow pass and
  1202   // the parser can have a minor difference of opinion about executability
  1203   // of bytecodes.  For example, "obj.field = null" is executable even
  1204   // if the field's type is an unloaded class; the flow pass used to
  1205   // make a trap for such code.
  1206   return NULL;
  1210 //-----------------------------stack_type_at-----------------------------------
  1211 const Type* Parse::Block::stack_type_at(int i) const {
  1212   return get_type(flow()->stack_type_at(i));
  1216 //-----------------------------local_type_at-----------------------------------
  1217 const Type* Parse::Block::local_type_at(int i) const {
  1218   // Make dead locals fall to bottom.
  1219   if (_live_locals.size() == 0) {
  1220     MethodLivenessResult live_locals = flow()->outer()->method()->liveness_at_bci(start());
  1221     // This bitmap can be zero length if we saw a breakpoint.
  1222     // In such cases, pretend they are all live.
  1223     ((Block*)this)->_live_locals = live_locals;
  1225   if (_live_locals.size() > 0 && !_live_locals.at(i))
  1226     return Type::BOTTOM;
  1228   return get_type(flow()->local_type_at(i));
  1232 #ifndef PRODUCT
  1234 //----------------------------name_for_bc--------------------------------------
  1235 // helper method for BytecodeParseHistogram
  1236 static const char* name_for_bc(int i) {
  1237   return Bytecodes::is_defined(i) ? Bytecodes::name(Bytecodes::cast(i)) : "xxxunusedxxx";
  1240 //----------------------------BytecodeParseHistogram------------------------------------
  1241 Parse::BytecodeParseHistogram::BytecodeParseHistogram(Parse *p, Compile *c) {
  1242   _parser   = p;
  1243   _compiler = c;
  1244   if( ! _initialized ) { _initialized = true; reset(); }
  1247 //----------------------------current_count------------------------------------
  1248 int Parse::BytecodeParseHistogram::current_count(BPHType bph_type) {
  1249   switch( bph_type ) {
  1250   case BPH_transforms: { return _parser->gvn().made_progress(); }
  1251   case BPH_values:     { return _parser->gvn().made_new_values(); }
  1252   default: { ShouldNotReachHere(); return 0; }
  1256 //----------------------------initialized--------------------------------------
  1257 bool Parse::BytecodeParseHistogram::initialized() { return _initialized; }
  1259 //----------------------------reset--------------------------------------------
  1260 void Parse::BytecodeParseHistogram::reset() {
  1261   int i = Bytecodes::number_of_codes;
  1262   while (i-- > 0) { _bytecodes_parsed[i] = 0; _nodes_constructed[i] = 0; _nodes_transformed[i] = 0; _new_values[i] = 0; }
  1265 //----------------------------set_initial_state--------------------------------
  1266 // Record info when starting to parse one bytecode
  1267 void Parse::BytecodeParseHistogram::set_initial_state( Bytecodes::Code bc ) {
  1268   if( PrintParseStatistics && !_parser->is_osr_parse() ) {
  1269     _initial_bytecode    = bc;
  1270     _initial_node_count  = _compiler->unique();
  1271     _initial_transforms  = current_count(BPH_transforms);
  1272     _initial_values      = current_count(BPH_values);
  1276 //----------------------------record_change--------------------------------
  1277 // Record results of parsing one bytecode
  1278 void Parse::BytecodeParseHistogram::record_change() {
  1279   if( PrintParseStatistics && !_parser->is_osr_parse() ) {
  1280     ++_bytecodes_parsed[_initial_bytecode];
  1281     _nodes_constructed [_initial_bytecode] += (_compiler->unique() - _initial_node_count);
  1282     _nodes_transformed [_initial_bytecode] += (current_count(BPH_transforms) - _initial_transforms);
  1283     _new_values        [_initial_bytecode] += (current_count(BPH_values)     - _initial_values);
  1288 //----------------------------print--------------------------------------------
  1289 void Parse::BytecodeParseHistogram::print(float cutoff) {
  1290   ResourceMark rm;
  1291   // print profile
  1292   int total  = 0;
  1293   int i      = 0;
  1294   for( i = 0; i < Bytecodes::number_of_codes; ++i ) { total += _bytecodes_parsed[i]; }
  1295   int abs_sum = 0;
  1296   tty->cr();   //0123456789012345678901234567890123456789012345678901234567890123456789
  1297   tty->print_cr("Histogram of %d parsed bytecodes:", total);
  1298   if( total == 0 ) { return; }
  1299   tty->cr();
  1300   tty->print_cr("absolute:  count of compiled bytecodes of this type");
  1301   tty->print_cr("relative:  percentage contribution to compiled nodes");
  1302   tty->print_cr("nodes   :  Average number of nodes constructed per bytecode");
  1303   tty->print_cr("rnodes  :  Significance towards total nodes constructed, (nodes*relative)");
  1304   tty->print_cr("transforms: Average amount of tranform progress per bytecode compiled");
  1305   tty->print_cr("values  :  Average number of node values improved per bytecode");
  1306   tty->print_cr("name    :  Bytecode name");
  1307   tty->cr();
  1308   tty->print_cr("  absolute  relative   nodes  rnodes  transforms  values   name");
  1309   tty->print_cr("----------------------------------------------------------------------");
  1310   while (--i > 0) {
  1311     int       abs = _bytecodes_parsed[i];
  1312     float     rel = abs * 100.0F / total;
  1313     float   nodes = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_constructed[i])/_bytecodes_parsed[i];
  1314     float  rnodes = _bytecodes_parsed[i] == 0 ? 0 :  rel * nodes;
  1315     float  xforms = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_transformed[i])/_bytecodes_parsed[i];
  1316     float  values = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _new_values       [i])/_bytecodes_parsed[i];
  1317     if (cutoff <= rel) {
  1318       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));
  1319       abs_sum += abs;
  1322   tty->print_cr("----------------------------------------------------------------------");
  1323   float rel_sum = abs_sum * 100.0F / total;
  1324   tty->print_cr("%10d  %7.2f%%    (cutoff = %.2f%%)", abs_sum, rel_sum, cutoff);
  1325   tty->print_cr("----------------------------------------------------------------------");
  1326   tty->cr();
  1328 #endif
  1330 //----------------------------load_state_from----------------------------------
  1331 // Load block/map/sp.  But not do not touch iter/bci.
  1332 void Parse::load_state_from(Block* block) {
  1333   set_block(block);
  1334   // load the block's JVM state:
  1335   set_map(block->start_map());
  1336   set_sp( block->start_sp());
  1340 //-----------------------------record_state------------------------------------
  1341 void Parse::Block::record_state(Parse* p) {
  1342   assert(!is_merged(), "can only record state once, on 1st inflow");
  1343   assert(start_sp() == p->sp(), "stack pointer must agree with ciTypeFlow");
  1344   set_start_map(p->stop());
  1348 //------------------------------do_one_block-----------------------------------
  1349 void Parse::do_one_block() {
  1350   if (TraceOptoParse) {
  1351     Block *b = block();
  1352     int ns = b->num_successors();
  1353     int nt = b->all_successors();
  1355     tty->print("Parsing block #%d at bci [%d,%d), successors: ",
  1356                   block()->rpo(), block()->start(), block()->limit());
  1357     for (int i = 0; i < nt; i++) {
  1358       tty->print((( i < ns) ? " %d" : " %d(e)"), b->successor_at(i)->rpo());
  1360     if (b->is_loop_head()) tty->print("  lphd");
  1361     tty->print_cr("");
  1364   assert(block()->is_merged(), "must be merged before being parsed");
  1365   block()->mark_parsed();
  1366   ++_blocks_parsed;
  1368   // Set iterator to start of block.
  1369   iter().reset_to_bci(block()->start());
  1371   CompileLog* log = C->log();
  1373   // Parse bytecodes
  1374   while (!stopped() && !failing()) {
  1375     iter().next();
  1377     // Learn the current bci from the iterator:
  1378     set_parse_bci(iter().cur_bci());
  1380     if (bci() == block()->limit()) {
  1381       // Do not walk into the next block until directed by do_all_blocks.
  1382       merge(bci());
  1383       break;
  1385     assert(bci() < block()->limit(), "bci still in block");
  1387     if (log != NULL) {
  1388       // Output an optional context marker, to help place actions
  1389       // that occur during parsing of this BC.  If there is no log
  1390       // output until the next context string, this context string
  1391       // will be silently ignored.
  1392       log->context()->reset();
  1393       log->context()->print_cr("<bc code='%d' bci='%d'/>", (int)bc(), bci());
  1396     if (block()->has_trap_at(bci())) {
  1397       // We must respect the flow pass's traps, because it will refuse
  1398       // to produce successors for trapping blocks.
  1399       int trap_index = block()->flow()->trap_index();
  1400       assert(trap_index != 0, "trap index must be valid");
  1401       uncommon_trap(trap_index);
  1402       break;
  1405     NOT_PRODUCT( parse_histogram()->set_initial_state(bc()); );
  1407 #ifdef ASSERT
  1408     int pre_bc_sp = sp();
  1409     int inputs, depth;
  1410     bool have_se = !stopped() && compute_stack_effects(inputs, depth);
  1411     assert(!have_se || pre_bc_sp >= inputs, "have enough stack to execute this BC");
  1412 #endif //ASSERT
  1414     do_one_bytecode();
  1416     assert(!have_se || stopped() || failing() || (sp() - pre_bc_sp) == depth, "correct depth prediction");
  1418     do_exceptions();
  1420     NOT_PRODUCT( parse_histogram()->record_change(); );
  1422     if (log != NULL)  log->context()->reset();  // done w/ this one
  1424     // Fall into next bytecode.  Each bytecode normally has 1 sequential
  1425     // successor which is typically made ready by visiting this bytecode.
  1426     // If the successor has several predecessors, then it is a merge
  1427     // point, starts a new basic block, and is handled like other basic blocks.
  1432 //------------------------------merge------------------------------------------
  1433 void Parse::set_parse_bci(int bci) {
  1434   set_bci(bci);
  1435   Node_Notes* nn = C->default_node_notes();
  1436   if (nn == NULL)  return;
  1438   // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
  1439   if (!DebugInlinedCalls && depth() > 1) {
  1440     return;
  1443   // Update the JVMS annotation, if present.
  1444   JVMState* jvms = nn->jvms();
  1445   if (jvms != NULL && jvms->bci() != bci) {
  1446     // Update the JVMS.
  1447     jvms = jvms->clone_shallow(C);
  1448     jvms->set_bci(bci);
  1449     nn->set_jvms(jvms);
  1453 //------------------------------merge------------------------------------------
  1454 // Merge the current mapping into the basic block starting at bci
  1455 void Parse::merge(int target_bci) {
  1456   Block* target = successor_for_bci(target_bci);
  1457   if (target == NULL) { handle_missing_successor(target_bci); return; }
  1458   assert(!target->is_ready(), "our arrival must be expected");
  1459   int pnum = target->next_path_num();
  1460   merge_common(target, pnum);
  1463 //-------------------------merge_new_path--------------------------------------
  1464 // Merge the current mapping into the basic block, using a new path
  1465 void Parse::merge_new_path(int target_bci) {
  1466   Block* target = successor_for_bci(target_bci);
  1467   if (target == NULL) { handle_missing_successor(target_bci); return; }
  1468   assert(!target->is_ready(), "new path into frozen graph");
  1469   int pnum = target->add_new_path();
  1470   merge_common(target, pnum);
  1473 //-------------------------merge_exception-------------------------------------
  1474 // Merge the current mapping into the basic block starting at bci
  1475 // The ex_oop must be pushed on the stack, unlike throw_to_exit.
  1476 void Parse::merge_exception(int target_bci) {
  1477   assert(sp() == 1, "must have only the throw exception on the stack");
  1478   Block* target = successor_for_bci(target_bci);
  1479   if (target == NULL) { handle_missing_successor(target_bci); return; }
  1480   assert(target->is_handler(), "exceptions are handled by special blocks");
  1481   int pnum = target->add_new_path();
  1482   merge_common(target, pnum);
  1485 //--------------------handle_missing_successor---------------------------------
  1486 void Parse::handle_missing_successor(int target_bci) {
  1487 #ifndef PRODUCT
  1488   Block* b = block();
  1489   int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
  1490   tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
  1491 #endif
  1492   ShouldNotReachHere();
  1495 //--------------------------merge_common---------------------------------------
  1496 void Parse::merge_common(Parse::Block* target, int pnum) {
  1497   if (TraceOptoParse) {
  1498     tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
  1501   // Zap extra stack slots to top
  1502   assert(sp() == target->start_sp(), "");
  1503   clean_stack(sp());
  1505   if (!target->is_merged()) {   // No prior mapping at this bci
  1506     if (TraceOptoParse) { tty->print(" with empty state");  }
  1508     // If this path is dead, do not bother capturing it as a merge.
  1509     // It is "as if" we had 1 fewer predecessors from the beginning.
  1510     if (stopped()) {
  1511       if (TraceOptoParse)  tty->print_cr(", but path is dead and doesn't count");
  1512       return;
  1515     // Record that a new block has been merged.
  1516     ++_blocks_merged;
  1518     // Make a region if we know there are multiple or unpredictable inputs.
  1519     // (Also, if this is a plain fall-through, we might see another region,
  1520     // which must not be allowed into this block's map.)
  1521     if (pnum > PhiNode::Input         // Known multiple inputs.
  1522         || target->is_handler()       // These have unpredictable inputs.
  1523         || target->is_loop_head()     // Known multiple inputs
  1524         || control()->is_Region()) {  // We must hide this guy.
  1525       // Add a Region to start the new basic block.  Phis will be added
  1526       // later lazily.
  1527       int edges = target->pred_count();
  1528       if (edges < pnum)  edges = pnum;  // might be a new path!
  1529       Node *r = new (C, edges+1) RegionNode(edges+1);
  1530       gvn().set_type(r, Type::CONTROL);
  1531       record_for_igvn(r);
  1532       // zap all inputs to NULL for debugging (done in Node(uint) constructor)
  1533       // for (int j = 1; j < edges+1; j++) { r->init_req(j, NULL); }
  1534       r->init_req(pnum, control());
  1535       set_control(r);
  1538     // Convert the existing Parser mapping into a mapping at this bci.
  1539     store_state_to(target);
  1540     assert(target->is_merged(), "do not come here twice");
  1542   } else {                      // Prior mapping at this bci
  1543     if (TraceOptoParse) {  tty->print(" with previous state"); }
  1545     // We must not manufacture more phis if the target is already parsed.
  1546     bool nophi = target->is_parsed();
  1548     SafePointNode* newin = map();// Hang on to incoming mapping
  1549     Block* save_block = block(); // Hang on to incoming block;
  1550     load_state_from(target);    // Get prior mapping
  1552     assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
  1553     assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
  1554     assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
  1555     assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
  1557     // Iterate over my current mapping and the old mapping.
  1558     // Where different, insert Phi functions.
  1559     // Use any existing Phi functions.
  1560     assert(control()->is_Region(), "must be merging to a region");
  1561     RegionNode* r = control()->as_Region();
  1563     // Compute where to merge into
  1564     // Merge incoming control path
  1565     r->init_req(pnum, newin->control());
  1567     if (pnum == 1) {            // Last merge for this Region?
  1568       if (!block()->flow()->is_irreducible_entry()) {
  1569         Node* result = _gvn.transform_no_reclaim(r);
  1570         if (r != result && TraceOptoParse) {
  1571           tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
  1574       record_for_igvn(r);
  1577     // Update all the non-control inputs to map:
  1578     assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
  1579     bool check_elide_phi = target->is_SEL_backedge(save_block);
  1580     for (uint j = 1; j < newin->req(); j++) {
  1581       Node* m = map()->in(j);   // Current state of target.
  1582       Node* n = newin->in(j);   // Incoming change to target state.
  1583       PhiNode* phi;
  1584       if (m->is_Phi() && m->as_Phi()->region() == r)
  1585         phi = m->as_Phi();
  1586       else
  1587         phi = NULL;
  1588       if (m != n) {             // Different; must merge
  1589         switch (j) {
  1590         // Frame pointer and Return Address never changes
  1591         case TypeFunc::FramePtr:// Drop m, use the original value
  1592         case TypeFunc::ReturnAdr:
  1593           break;
  1594         case TypeFunc::Memory:  // Merge inputs to the MergeMem node
  1595           assert(phi == NULL, "the merge contains phis, not vice versa");
  1596           merge_memory_edges(n->as_MergeMem(), pnum, nophi);
  1597           continue;
  1598         default:                // All normal stuff
  1599           if (phi == NULL) {
  1600             if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
  1601               phi = ensure_phi(j, nophi);
  1604           break;
  1607       // At this point, n might be top if:
  1608       //  - there is no phi (because TypeFlow detected a conflict), or
  1609       //  - the corresponding control edges is top (a dead incoming path)
  1610       // It is a bug if we create a phi which sees a garbage value on a live path.
  1612       if (phi != NULL) {
  1613         assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
  1614         assert(phi->region() == r, "");
  1615         phi->set_req(pnum, n);  // Then add 'n' to the merge
  1616         if (pnum == PhiNode::Input) {
  1617           // Last merge for this Phi.
  1618           // So far, Phis have had a reasonable type from ciTypeFlow.
  1619           // Now _gvn will join that with the meet of current inputs.
  1620           // BOTTOM is never permissible here, 'cause pessimistically
  1621           // Phis of pointers cannot lose the basic pointer type.
  1622           debug_only(const Type* bt1 = phi->bottom_type());
  1623           assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
  1624           map()->set_req(j, _gvn.transform_no_reclaim(phi));
  1625           debug_only(const Type* bt2 = phi->bottom_type());
  1626           assert(bt2->higher_equal(bt1), "must be consistent with type-flow");
  1627           record_for_igvn(phi);
  1630     } // End of for all values to be merged
  1632     if (pnum == PhiNode::Input &&
  1633         !r->in(0)) {         // The occasional useless Region
  1634       assert(control() == r, "");
  1635       set_control(r->nonnull_req());
  1638     // newin has been subsumed into the lazy merge, and is now dead.
  1639     set_block(save_block);
  1641     stop();                     // done with this guy, for now
  1644   if (TraceOptoParse) {
  1645     tty->print_cr(" on path %d", pnum);
  1648   // Done with this parser state.
  1649   assert(stopped(), "");
  1653 //--------------------------merge_memory_edges---------------------------------
  1654 void Parse::merge_memory_edges(MergeMemNode* n, int pnum, bool nophi) {
  1655   // (nophi means we must not create phis, because we already parsed here)
  1656   assert(n != NULL, "");
  1657   // Merge the inputs to the MergeMems
  1658   MergeMemNode* m = merged_memory();
  1660   assert(control()->is_Region(), "must be merging to a region");
  1661   RegionNode* r = control()->as_Region();
  1663   PhiNode* base = NULL;
  1664   MergeMemNode* remerge = NULL;
  1665   for (MergeMemStream mms(m, n); mms.next_non_empty2(); ) {
  1666     Node *p = mms.force_memory();
  1667     Node *q = mms.memory2();
  1668     if (mms.is_empty() && nophi) {
  1669       // Trouble:  No new splits allowed after a loop body is parsed.
  1670       // Instead, wire the new split into a MergeMem on the backedge.
  1671       // The optimizer will sort it out, slicing the phi.
  1672       if (remerge == NULL) {
  1673         assert(base != NULL, "");
  1674         assert(base->in(0) != NULL, "should not be xformed away");
  1675         remerge = MergeMemNode::make(C, base->in(pnum));
  1676         gvn().set_type(remerge, Type::MEMORY);
  1677         base->set_req(pnum, remerge);
  1679       remerge->set_memory_at(mms.alias_idx(), q);
  1680       continue;
  1682     assert(!q->is_MergeMem(), "");
  1683     PhiNode* phi;
  1684     if (p != q) {
  1685       phi = ensure_memory_phi(mms.alias_idx(), nophi);
  1686     } else {
  1687       if (p->is_Phi() && p->as_Phi()->region() == r)
  1688         phi = p->as_Phi();
  1689       else
  1690         phi = NULL;
  1692     // Insert q into local phi
  1693     if (phi != NULL) {
  1694       assert(phi->region() == r, "");
  1695       p = phi;
  1696       phi->set_req(pnum, q);
  1697       if (mms.at_base_memory()) {
  1698         base = phi;  // delay transforming it
  1699       } else if (pnum == 1) {
  1700         record_for_igvn(phi);
  1701         p = _gvn.transform_no_reclaim(phi);
  1703       mms.set_memory(p);// store back through the iterator
  1706   // Transform base last, in case we must fiddle with remerging.
  1707   if (base != NULL && pnum == 1) {
  1708     record_for_igvn(base);
  1709     m->set_base_memory( _gvn.transform_no_reclaim(base) );
  1714 //------------------------ensure_phis_everywhere-------------------------------
  1715 void Parse::ensure_phis_everywhere() {
  1716   ensure_phi(TypeFunc::I_O);
  1718   // Ensure a phi on all currently known memories.
  1719   for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
  1720     ensure_memory_phi(mms.alias_idx());
  1721     debug_only(mms.set_memory());  // keep the iterator happy
  1724   // Note:  This is our only chance to create phis for memory slices.
  1725   // If we miss a slice that crops up later, it will have to be
  1726   // merged into the base-memory phi that we are building here.
  1727   // Later, the optimizer will comb out the knot, and build separate
  1728   // phi-loops for each memory slice that matters.
  1730   // Monitors must nest nicely and not get confused amongst themselves.
  1731   // Phi-ify everything up to the monitors, though.
  1732   uint monoff = map()->jvms()->monoff();
  1733   uint nof_monitors = map()->jvms()->nof_monitors();
  1735   assert(TypeFunc::Parms == map()->jvms()->locoff(), "parser map should contain only youngest jvms");
  1736   bool check_elide_phi = block()->is_SEL_head();
  1737   for (uint i = TypeFunc::Parms; i < monoff; i++) {
  1738     if (!check_elide_phi || !block()->can_elide_SEL_phi(i)) {
  1739       ensure_phi(i);
  1743   // Even monitors need Phis, though they are well-structured.
  1744   // This is true for OSR methods, and also for the rare cases where
  1745   // a monitor object is the subject of a replace_in_map operation.
  1746   // See bugs 4426707 and 5043395.
  1747   for (uint m = 0; m < nof_monitors; m++) {
  1748     ensure_phi(map()->jvms()->monitor_obj_offset(m));
  1753 //-----------------------------add_new_path------------------------------------
  1754 // Add a previously unaccounted predecessor to this block.
  1755 int Parse::Block::add_new_path() {
  1756   // If there is no map, return the lowest unused path number.
  1757   if (!is_merged())  return pred_count()+1;  // there will be a map shortly
  1759   SafePointNode* map = start_map();
  1760   if (!map->control()->is_Region())
  1761     return pred_count()+1;  // there may be a region some day
  1762   RegionNode* r = map->control()->as_Region();
  1764   // Add new path to the region.
  1765   uint pnum = r->req();
  1766   r->add_req(NULL);
  1768   for (uint i = 1; i < map->req(); i++) {
  1769     Node* n = map->in(i);
  1770     if (i == TypeFunc::Memory) {
  1771       // Ensure a phi on all currently known memories.
  1772       for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
  1773         Node* phi = mms.memory();
  1774         if (phi->is_Phi() && phi->as_Phi()->region() == r) {
  1775           assert(phi->req() == pnum, "must be same size as region");
  1776           phi->add_req(NULL);
  1779     } else {
  1780       if (n->is_Phi() && n->as_Phi()->region() == r) {
  1781         assert(n->req() == pnum, "must be same size as region");
  1782         n->add_req(NULL);
  1787   return pnum;
  1790 //------------------------------ensure_phi-------------------------------------
  1791 // Turn the idx'th entry of the current map into a Phi
  1792 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
  1793   SafePointNode* map = this->map();
  1794   Node* region = map->control();
  1795   assert(region->is_Region(), "");
  1797   Node* o = map->in(idx);
  1798   assert(o != NULL, "");
  1800   if (o == top())  return NULL; // TOP always merges into TOP
  1802   if (o->is_Phi() && o->as_Phi()->region() == region) {
  1803     return o->as_Phi();
  1806   // Now use a Phi here for merging
  1807   assert(!nocreate, "Cannot build a phi for a block already parsed.");
  1808   const JVMState* jvms = map->jvms();
  1809   const Type* t;
  1810   if (jvms->is_loc(idx)) {
  1811     t = block()->local_type_at(idx - jvms->locoff());
  1812   } else if (jvms->is_stk(idx)) {
  1813     t = block()->stack_type_at(idx - jvms->stkoff());
  1814   } else if (jvms->is_mon(idx)) {
  1815     assert(!jvms->is_monitor_box(idx), "no phis for boxes");
  1816     t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
  1817   } else if ((uint)idx < TypeFunc::Parms) {
  1818     t = o->bottom_type();  // Type::RETURN_ADDRESS or such-like.
  1819   } else {
  1820     assert(false, "no type information for this phi");
  1823   // If the type falls to bottom, then this must be a local that
  1824   // is mixing ints and oops or some such.  Forcing it to top
  1825   // makes it go dead.
  1826   if (t == Type::BOTTOM) {
  1827     map->set_req(idx, top());
  1828     return NULL;
  1831   // Do not create phis for top either.
  1832   // A top on a non-null control flow must be an unused even after the.phi.
  1833   if (t == Type::TOP || t == Type::HALF) {
  1834     map->set_req(idx, top());
  1835     return NULL;
  1838   PhiNode* phi = PhiNode::make(region, o, t);
  1839   gvn().set_type(phi, t);
  1840   if (C->do_escape_analysis()) record_for_igvn(phi);
  1841   map->set_req(idx, phi);
  1842   return phi;
  1845 //--------------------------ensure_memory_phi----------------------------------
  1846 // Turn the idx'th slice of the current memory into a Phi
  1847 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
  1848   MergeMemNode* mem = merged_memory();
  1849   Node* region = control();
  1850   assert(region->is_Region(), "");
  1852   Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
  1853   assert(o != NULL && o != top(), "");
  1855   PhiNode* phi;
  1856   if (o->is_Phi() && o->as_Phi()->region() == region) {
  1857     phi = o->as_Phi();
  1858     if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
  1859       // clone the shared base memory phi to make a new memory split
  1860       assert(!nocreate, "Cannot build a phi for a block already parsed.");
  1861       const Type* t = phi->bottom_type();
  1862       const TypePtr* adr_type = C->get_adr_type(idx);
  1863       phi = phi->slice_memory(adr_type);
  1864       gvn().set_type(phi, t);
  1866     return phi;
  1869   // Now use a Phi here for merging
  1870   assert(!nocreate, "Cannot build a phi for a block already parsed.");
  1871   const Type* t = o->bottom_type();
  1872   const TypePtr* adr_type = C->get_adr_type(idx);
  1873   phi = PhiNode::make(region, o, t, adr_type);
  1874   gvn().set_type(phi, t);
  1875   if (idx == Compile::AliasIdxBot)
  1876     mem->set_base_memory(phi);
  1877   else
  1878     mem->set_memory_at(idx, phi);
  1879   return phi;
  1882 //------------------------------call_register_finalizer-----------------------
  1883 // Check the klass of the receiver and call register_finalizer if the
  1884 // class need finalization.
  1885 void Parse::call_register_finalizer() {
  1886   Node* receiver = local(0);
  1887   assert(receiver != NULL && receiver->bottom_type()->isa_instptr() != NULL,
  1888          "must have non-null instance type");
  1890   const TypeInstPtr *tinst = receiver->bottom_type()->isa_instptr();
  1891   if (tinst != NULL && tinst->klass()->is_loaded() && !tinst->klass_is_exact()) {
  1892     // The type isn't known exactly so see if CHA tells us anything.
  1893     ciInstanceKlass* ik = tinst->klass()->as_instance_klass();
  1894     if (!Dependencies::has_finalizable_subclass(ik)) {
  1895       // No finalizable subclasses so skip the dynamic check.
  1896       C->dependencies()->assert_has_no_finalizable_subclasses(ik);
  1897       return;
  1901   // Insert a dynamic test for whether the instance needs
  1902   // finalization.  In general this will fold up since the concrete
  1903   // class is often visible so the access flags are constant.
  1904   Node* klass_addr = basic_plus_adr( receiver, receiver, oopDesc::klass_offset_in_bytes() );
  1905   Node* klass = _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), klass_addr, TypeInstPtr::KLASS) );
  1907   Node* access_flags_addr = basic_plus_adr(klass, klass, Klass::access_flags_offset_in_bytes() + sizeof(oopDesc));
  1908   Node* access_flags = make_load(NULL, access_flags_addr, TypeInt::INT, T_INT);
  1910   Node* mask  = _gvn.transform(new (C, 3) AndINode(access_flags, intcon(JVM_ACC_HAS_FINALIZER)));
  1911   Node* check = _gvn.transform(new (C, 3) CmpINode(mask, intcon(0)));
  1912   Node* test  = _gvn.transform(new (C, 2) BoolNode(check, BoolTest::ne));
  1914   IfNode* iff = create_and_map_if(control(), test, PROB_MAX, COUNT_UNKNOWN);
  1916   RegionNode* result_rgn = new (C, 3) RegionNode(3);
  1917   record_for_igvn(result_rgn);
  1919   Node *skip_register = _gvn.transform(new (C, 1) IfFalseNode(iff));
  1920   result_rgn->init_req(1, skip_register);
  1922   Node *needs_register = _gvn.transform(new (C, 1) IfTrueNode(iff));
  1923   set_control(needs_register);
  1924   if (stopped()) {
  1925     // There is no slow path.
  1926     result_rgn->init_req(2, top());
  1927   } else {
  1928     Node *call = make_runtime_call(RC_NO_LEAF,
  1929                                    OptoRuntime::register_finalizer_Type(),
  1930                                    OptoRuntime::register_finalizer_Java(),
  1931                                    NULL, TypePtr::BOTTOM,
  1932                                    receiver);
  1933     make_slow_call_ex(call, env()->Throwable_klass(), true);
  1935     Node* fast_io  = call->in(TypeFunc::I_O);
  1936     Node* fast_mem = call->in(TypeFunc::Memory);
  1937     // These two phis are pre-filled with copies of of the fast IO and Memory
  1938     Node* io_phi   = PhiNode::make(result_rgn, fast_io,  Type::ABIO);
  1939     Node* mem_phi  = PhiNode::make(result_rgn, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
  1941     result_rgn->init_req(2, control());
  1942     io_phi    ->init_req(2, i_o());
  1943     mem_phi   ->init_req(2, reset_memory());
  1945     set_all_memory( _gvn.transform(mem_phi) );
  1946     set_i_o(        _gvn.transform(io_phi) );
  1949   set_control( _gvn.transform(result_rgn) );
  1952 //------------------------------return_current---------------------------------
  1953 // Append current _map to _exit_return
  1954 void Parse::return_current(Node* value) {
  1955   if (RegisterFinalizersAtInit &&
  1956       method()->intrinsic_id() == vmIntrinsics::_Object_init) {
  1957     call_register_finalizer();
  1960   // Do not set_parse_bci, so that return goo is credited to the return insn.
  1961   set_bci(InvocationEntryBci);
  1962   if (method()->is_synchronized() && GenerateSynchronizationCode) {
  1963     shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
  1965   if (C->env()->dtrace_method_probes()) {
  1966     make_dtrace_method_exit(method());
  1968   SafePointNode* exit_return = _exits.map();
  1969   exit_return->in( TypeFunc::Control  )->add_req( control() );
  1970   exit_return->in( TypeFunc::I_O      )->add_req( i_o    () );
  1971   Node *mem = exit_return->in( TypeFunc::Memory   );
  1972   for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
  1973     if (mms.is_empty()) {
  1974       // get a copy of the base memory, and patch just this one input
  1975       const TypePtr* adr_type = mms.adr_type(C);
  1976       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
  1977       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
  1978       gvn().set_type_bottom(phi);
  1979       phi->del_req(phi->req()-1);  // prepare to re-patch
  1980       mms.set_memory(phi);
  1982     mms.memory()->add_req(mms.memory2());
  1985   // frame pointer is always same, already captured
  1986   if (value != NULL) {
  1987     // If returning oops to an interface-return, there is a silent free
  1988     // cast from oop to interface allowed by the Verifier.  Make it explicit
  1989     // here.
  1990     Node* phi = _exits.argument(0);
  1991     const TypeInstPtr *tr = phi->bottom_type()->isa_instptr();
  1992     if( tr && tr->klass()->is_loaded() &&
  1993         tr->klass()->is_interface() ) {
  1994       const TypeInstPtr *tp = value->bottom_type()->isa_instptr();
  1995       if (tp && tp->klass()->is_loaded() &&
  1996           !tp->klass()->is_interface()) {
  1997         // sharpen the type eagerly; this eases certain assert checking
  1998         if (tp->higher_equal(TypeInstPtr::NOTNULL))
  1999           tr = tr->join(TypeInstPtr::NOTNULL)->is_instptr();
  2000         value = _gvn.transform(new (C, 2) CheckCastPPNode(0,value,tr));
  2003     phi->add_req(value);
  2006   stop_and_kill_map();          // This CFG path dies here
  2010 //------------------------------add_safepoint----------------------------------
  2011 void Parse::add_safepoint() {
  2012   // See if we can avoid this safepoint.  No need for a SafePoint immediately
  2013   // after a Call (except Leaf Call) or another SafePoint.
  2014   Node *proj = control();
  2015   bool add_poll_param = SafePointNode::needs_polling_address_input();
  2016   uint parms = add_poll_param ? TypeFunc::Parms+1 : TypeFunc::Parms;
  2017   if( proj->is_Proj() ) {
  2018     Node *n0 = proj->in(0);
  2019     if( n0->is_Catch() ) {
  2020       n0 = n0->in(0)->in(0);
  2021       assert( n0->is_Call(), "expect a call here" );
  2023     if( n0->is_Call() ) {
  2024       if( n0->as_Call()->guaranteed_safepoint() )
  2025         return;
  2026     } else if( n0->is_SafePoint() && n0->req() >= parms ) {
  2027       return;
  2031   // Clear out dead values from the debug info.
  2032   kill_dead_locals();
  2034   // Clone the JVM State
  2035   SafePointNode *sfpnt = new (C, parms) SafePointNode(parms, NULL);
  2037   // Capture memory state BEFORE a SafePoint.  Since we can block at a
  2038   // SafePoint we need our GC state to be safe; i.e. we need all our current
  2039   // write barriers (card marks) to not float down after the SafePoint so we
  2040   // must read raw memory.  Likewise we need all oop stores to match the card
  2041   // marks.  If deopt can happen, we need ALL stores (we need the correct JVM
  2042   // state on a deopt).
  2044   // We do not need to WRITE the memory state after a SafePoint.  The control
  2045   // edge will keep card-marks and oop-stores from floating up from below a
  2046   // SafePoint and our true dependency added here will keep them from floating
  2047   // down below a SafePoint.
  2049   // Clone the current memory state
  2050   Node* mem = MergeMemNode::make(C, map()->memory());
  2052   mem = _gvn.transform(mem);
  2054   // Pass control through the safepoint
  2055   sfpnt->init_req(TypeFunc::Control  , control());
  2056   // Fix edges normally used by a call
  2057   sfpnt->init_req(TypeFunc::I_O      , top() );
  2058   sfpnt->init_req(TypeFunc::Memory   , mem   );
  2059   sfpnt->init_req(TypeFunc::ReturnAdr, top() );
  2060   sfpnt->init_req(TypeFunc::FramePtr , top() );
  2062   // Create a node for the polling address
  2063   if( add_poll_param ) {
  2064     Node *polladr = ConPNode::make(C, (address)os::get_polling_page());
  2065     sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
  2068   // Fix up the JVM State edges
  2069   add_safepoint_edges(sfpnt);
  2070   Node *transformed_sfpnt = _gvn.transform(sfpnt);
  2071   set_control(transformed_sfpnt);
  2073   // Provide an edge from root to safepoint.  This makes the safepoint
  2074   // appear useful until the parse has completed.
  2075   if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
  2076     assert(C->root() != NULL, "Expect parse is still valid");
  2077     C->root()->add_prec(transformed_sfpnt);
  2081 #ifndef PRODUCT
  2082 //------------------------show_parse_info--------------------------------------
  2083 void Parse::show_parse_info() {
  2084   InlineTree* ilt = NULL;
  2085   if (C->ilt() != NULL) {
  2086     JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
  2087     ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
  2089   if (PrintCompilation && Verbose) {
  2090     if (depth() == 1) {
  2091       if( ilt->count_inlines() ) {
  2092         tty->print("    __inlined %d (%d bytes)", ilt->count_inlines(),
  2093                      ilt->count_inline_bcs());
  2094         tty->cr();
  2096     } else {
  2097       if (method()->is_synchronized())         tty->print("s");
  2098       if (method()->has_exception_handlers())  tty->print("!");
  2099       // Check this is not the final compiled version
  2100       if (C->trap_can_recompile()) {
  2101         tty->print("-");
  2102       } else {
  2103         tty->print(" ");
  2105       method()->print_short_name();
  2106       if (is_osr_parse()) {
  2107         tty->print(" @ %d", osr_bci());
  2109       tty->print(" (%d bytes)",method()->code_size());
  2110       if (ilt->count_inlines()) {
  2111         tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
  2112                    ilt->count_inline_bcs());
  2114       tty->cr();
  2117   if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
  2118     // Print that we succeeded; suppress this message on the first osr parse.
  2120     if (method()->is_synchronized())         tty->print("s");
  2121     if (method()->has_exception_handlers())  tty->print("!");
  2122     // Check this is not the final compiled version
  2123     if (C->trap_can_recompile() && depth() == 1) {
  2124       tty->print("-");
  2125     } else {
  2126       tty->print(" ");
  2128     if( depth() != 1 ) { tty->print("   "); }  // missing compile count
  2129     for (int i = 1; i < depth(); ++i) { tty->print("  "); }
  2130     method()->print_short_name();
  2131     if (is_osr_parse()) {
  2132       tty->print(" @ %d", osr_bci());
  2134     if (ilt->caller_bci() != -1) {
  2135       tty->print(" @ %d", ilt->caller_bci());
  2137     tty->print(" (%d bytes)",method()->code_size());
  2138     if (ilt->count_inlines()) {
  2139       tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
  2140                  ilt->count_inline_bcs());
  2142     tty->cr();
  2147 //------------------------------dump-------------------------------------------
  2148 // Dump information associated with the bytecodes of current _method
  2149 void Parse::dump() {
  2150   if( method() != NULL ) {
  2151     // Iterate over bytecodes
  2152     ciBytecodeStream iter(method());
  2153     for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
  2154       dump_bci( iter.cur_bci() );
  2155       tty->cr();
  2160 // Dump information associated with a byte code index, 'bci'
  2161 void Parse::dump_bci(int bci) {
  2162   // Output info on merge-points, cloning, and within _jsr..._ret
  2163   // NYI
  2164   tty->print(" bci:%d", bci);
  2167 #endif

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