src/share/vm/opto/parse1.cpp

Sat, 19 Oct 2013 12:16:43 +0200

author
roland
date
Sat, 19 Oct 2013 12:16:43 +0200
changeset 5981
3213ba4d3dff
parent 5110
6f3fd5150b67
child 5991
b2ee5dc63353
permissions
-rw-r--r--

8024069: replace_in_map() should operate on parent maps
Summary: type information gets lost because replace_in_map() doesn't update parent maps
Reviewed-by: kvn, twisti

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

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