1 /*
   2  * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "compiler/compileLog.hpp"
  27 #include "interpreter/linkResolver.hpp"
  28 #include "memory/resourceArea.hpp"
  29 #include "oops/method.hpp"
  30 #include "opto/addnode.hpp"
  31 #include "opto/c2compiler.hpp"
  32 #include "opto/castnode.hpp"
  33 #include "opto/idealGraphPrinter.hpp"
  34 #include "opto/locknode.hpp"
  35 #include "opto/memnode.hpp"
  36 #include "opto/opaquenode.hpp"
  37 #include "opto/parse.hpp"
  38 #include "opto/rootnode.hpp"
  39 #include "opto/runtime.hpp"
  40 #include "opto/valuetypenode.hpp"
  41 #include "runtime/arguments.hpp"
  42 #include "runtime/handles.inline.hpp"
  43 #include "runtime/safepointMechanism.hpp"
  44 #include "runtime/sharedRuntime.hpp"
  45 #include "utilities/copy.hpp"
  46 
  47 // Static array so we can figure out which bytecodes stop us from compiling
  48 // the most. Some of the non-static variables are needed in bytecodeInfo.cpp
  49 // and eventually should be encapsulated in a proper class (gri 8/18/98).
  50 
  51 #ifndef PRODUCT
  52 int nodes_created              = 0;
  53 int methods_parsed             = 0;
  54 int methods_seen               = 0;
  55 int blocks_parsed              = 0;
  56 int blocks_seen                = 0;
  57 
  58 int explicit_null_checks_inserted = 0;
  59 int explicit_null_checks_elided   = 0;
  60 int all_null_checks_found         = 0;
  61 int implicit_null_checks          = 0;
  62 
  63 bool Parse::BytecodeParseHistogram::_initialized = false;
  64 uint Parse::BytecodeParseHistogram::_bytecodes_parsed [Bytecodes::number_of_codes];
  65 uint Parse::BytecodeParseHistogram::_nodes_constructed[Bytecodes::number_of_codes];
  66 uint Parse::BytecodeParseHistogram::_nodes_transformed[Bytecodes::number_of_codes];
  67 uint Parse::BytecodeParseHistogram::_new_values       [Bytecodes::number_of_codes];
  68 
  69 //------------------------------print_statistics-------------------------------
  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   }
  78   tty->print_cr("Blocks parsed: %d  Blocks seen: %d", blocks_parsed, blocks_seen);
  79 
  80   if (explicit_null_checks_inserted) {
  81     tty->print_cr("%d original NULL checks - %d elided (%2d%%); optimizer leaves %d,",
  82                   explicit_null_checks_inserted, explicit_null_checks_elided,
  83                   (100*explicit_null_checks_elided)/explicit_null_checks_inserted,
  84                   all_null_checks_found);
  85   }
  86   if (all_null_checks_found) {
  87     tty->print_cr("%d made implicit (%2d%%)", implicit_null_checks,
  88                   (100*implicit_null_checks)/all_null_checks_found);
  89   }
  90   if (SharedRuntime::_implicit_null_throws) {
  91     tty->print_cr("%d implicit null exceptions at runtime",
  92                   SharedRuntime::_implicit_null_throws);
  93   }
  94 
  95   if (PrintParseStatistics && BytecodeParseHistogram::initialized()) {
  96     BytecodeParseHistogram::print();
  97   }
  98 }
  99 #endif
 100 
 101 //------------------------------ON STACK REPLACEMENT---------------------------
 102 
 103 // Construct a node which can be used to get incoming state for
 104 // on stack replacement.
 105 Node* Parse::fetch_interpreter_state(int index,
 106                                      const Type* type,
 107                                      Node* local_addrs,
 108                                      Node* local_addrs_base) {
 109   BasicType bt = type->basic_type();
 110   if (type == TypePtr::NULL_PTR) {
 111     // Ptr types are mixed together with T_ADDRESS but NULL is
 112     // really for T_OBJECT types so correct it.
 113     bt = T_OBJECT;
 114   }
 115   Node *mem = memory(Compile::AliasIdxRaw);
 116   Node *adr = basic_plus_adr( local_addrs_base, local_addrs, -index*wordSize );
 117   Node *ctl = control();
 118 
 119   // Very similar to LoadNode::make, except we handle un-aligned longs and
 120   // doubles on Sparc.  Intel can handle them just fine directly.
 121   Node *l = NULL;
 122   switch (bt) {                // Signature is flattened
 123   case T_INT:     l = new LoadINode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInt::INT,        MemNode::unordered); break;
 124   case T_FLOAT:   l = new LoadFNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::FLOAT,         MemNode::unordered); break;
 125   case T_ADDRESS: l = new LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM,  MemNode::unordered); break;
 126   case T_OBJECT:  l = new LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeInstPtr::BOTTOM, MemNode::unordered); break;
 127   case T_VALUETYPE: {
 128     // Load oop and create a new ValueTypeNode
 129     const TypeInstPtr* ptr_type = TypeInstPtr::make(TypePtr::BotPTR, type->is_valuetype()->value_klass());
 130     l = _gvn.transform(new LoadPNode(ctl, mem, adr, TypeRawPtr::BOTTOM, ptr_type, MemNode::unordered));
 131     l = ValueTypeNode::make_from_oop(this, l, type->is_valuetype()->value_klass(), /* buffer_check */ true, /* null2default */ false);
 132     break;
 133   }
 134   case T_LONG:
 135   case T_DOUBLE: {
 136     // Since arguments are in reverse order, the argument address 'adr'
 137     // refers to the back half of the long/double.  Recompute adr.
 138     adr = basic_plus_adr(local_addrs_base, local_addrs, -(index+1)*wordSize);
 139     if (Matcher::misaligned_doubles_ok) {
 140       l = (bt == T_DOUBLE)
 141         ? (Node*)new LoadDNode(ctl, mem, adr, TypeRawPtr::BOTTOM, Type::DOUBLE, MemNode::unordered)
 142         : (Node*)new LoadLNode(ctl, mem, adr, TypeRawPtr::BOTTOM, TypeLong::LONG, MemNode::unordered);
 143     } else {
 144       l = (bt == T_DOUBLE)
 145         ? (Node*)new LoadD_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered)
 146         : (Node*)new LoadL_unalignedNode(ctl, mem, adr, TypeRawPtr::BOTTOM, MemNode::unordered);
 147     }
 148     break;
 149   }
 150   default: ShouldNotReachHere();
 151   }
 152   return _gvn.transform(l);
 153 }
 154 
 155 // Helper routine to prevent the interpreter from handing
 156 // unexpected typestate to an OSR method.
 157 // The Node l is a value newly dug out of the interpreter frame.
 158 // The type is the type predicted by ciTypeFlow.  Note that it is
 159 // not a general type, but can only come from Type::get_typeflow_type.
 160 // The safepoint is a map which will feed an uncommon trap.
 161 Node* Parse::check_interpreter_type(Node* l, const Type* type,
 162                                     SafePointNode* &bad_type_exit) {
 163 
 164   const TypeOopPtr* tp = type->isa_oopptr();
 165 
 166   // TypeFlow may assert null-ness if a type appears unloaded.
 167   if (type == TypePtr::NULL_PTR ||
 168       (tp != NULL && !tp->klass()->is_loaded())) {
 169     // Value must be null, not a real oop.
 170     Node* chk = _gvn.transform( new CmpPNode(l, null()) );
 171     Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
 172     IfNode* iff = create_and_map_if(control(), tst, PROB_MAX, COUNT_UNKNOWN);
 173     set_control(_gvn.transform( new IfTrueNode(iff) ));
 174     Node* bad_type = _gvn.transform( new IfFalseNode(iff) );
 175     bad_type_exit->control()->add_req(bad_type);
 176     l = null();
 177   }
 178 
 179   // Typeflow can also cut off paths from the CFG, based on
 180   // types which appear unloaded, or call sites which appear unlinked.
 181   // When paths are cut off, values at later merge points can rise
 182   // toward more specific classes.  Make sure these specific classes
 183   // are still in effect.
 184   if (tp != NULL && tp->klass() != C->env()->Object_klass()) {
 185     // TypeFlow asserted a specific object type.  Value must have that type.
 186     Node* bad_type_ctrl = NULL;
 187     l = gen_checkcast(l, makecon(TypeKlassPtr::make(tp->klass())), &bad_type_ctrl);
 188     bad_type_exit->control()->add_req(bad_type_ctrl);
 189   }
 190 
 191   BasicType bt_l = _gvn.type(l)->basic_type();
 192   BasicType bt_t = type->basic_type();
 193   assert(_gvn.type(l)->higher_equal(type), "must constrain OSR typestate");
 194   return l;
 195 }
 196 
 197 // Helper routine which sets up elements of the initial parser map when
 198 // performing a parse for on stack replacement.  Add values into map.
 199 // The only parameter contains the address of a interpreter arguments.
 200 void Parse::load_interpreter_state(Node* osr_buf) {
 201   int index;
 202   int max_locals = jvms()->loc_size();
 203   int max_stack  = jvms()->stk_size();
 204 
 205   // Mismatch between method and jvms can occur since map briefly held
 206   // an OSR entry state (which takes up one RawPtr word).
 207   assert(max_locals == method()->max_locals(), "sanity");
 208   assert(max_stack  >= method()->max_stack(),  "sanity");
 209   assert((int)jvms()->endoff() == TypeFunc::Parms + max_locals + max_stack, "sanity");
 210   assert((int)jvms()->endoff() == (int)map()->req(), "sanity");
 211 
 212   // Find the start block.
 213   Block* osr_block = start_block();
 214   assert(osr_block->start() == osr_bci(), "sanity");
 215 
 216   // Set initial BCI.
 217   set_parse_bci(osr_block->start());
 218 
 219   // Set initial stack depth.
 220   set_sp(osr_block->start_sp());
 221 
 222   // Check bailouts.  We currently do not perform on stack replacement
 223   // of loops in catch blocks or loops which branch with a non-empty stack.
 224   if (sp() != 0) {
 225     C->record_method_not_compilable("OSR starts with non-empty stack");
 226     return;
 227   }
 228   // Do not OSR inside finally clauses:
 229   if (osr_block->has_trap_at(osr_block->start())) {
 230     C->record_method_not_compilable("OSR starts with an immediate trap");
 231     return;
 232   }
 233 
 234   // Commute monitors from interpreter frame to compiler frame.
 235   assert(jvms()->monitor_depth() == 0, "should be no active locks at beginning of osr");
 236   int mcnt = osr_block->flow()->monitor_count();
 237   Node *monitors_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals+mcnt*2-1)*wordSize);
 238   for (index = 0; index < mcnt; index++) {
 239     // Make a BoxLockNode for the monitor.
 240     Node *box = _gvn.transform(new BoxLockNode(next_monitor()));
 241 
 242     // Displaced headers and locked objects are interleaved in the
 243     // temp OSR buffer.  We only copy the locked objects out here.
 244     // Fetch the locked object from the OSR temp buffer and copy to our fastlock node.
 245     Node* lock_object = fetch_interpreter_state(index*2, Type::get_const_basic_type(T_OBJECT), monitors_addr, osr_buf);
 246     // Try and copy the displaced header to the BoxNode
 247     Node* displaced_hdr = fetch_interpreter_state((index*2) + 1, Type::get_const_basic_type(T_ADDRESS), monitors_addr, osr_buf);
 248 
 249     store_to_memory(control(), box, displaced_hdr, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
 250 
 251     // Build a bogus FastLockNode (no code will be generated) and push the
 252     // monitor into our debug info.
 253     const FastLockNode *flock = _gvn.transform(new FastLockNode( 0, lock_object, box ))->as_FastLock();
 254     map()->push_monitor(flock);
 255 
 256     // If the lock is our method synchronization lock, tuck it away in
 257     // _sync_lock for return and rethrow exit paths.
 258     if (index == 0 && method()->is_synchronized()) {
 259       _synch_lock = flock;
 260     }
 261   }
 262 
 263   // Use the raw liveness computation to make sure that unexpected
 264   // values don't propagate into the OSR frame.
 265   MethodLivenessResult live_locals = method()->liveness_at_bci(osr_bci());
 266   if (!live_locals.is_valid()) {
 267     // Degenerate or breakpointed method.
 268     C->record_method_not_compilable("OSR in empty or breakpointed method");
 269     return;
 270   }
 271 
 272   // Extract the needed locals from the interpreter frame.
 273   Node *locals_addr = basic_plus_adr(osr_buf, osr_buf, (max_locals-1)*wordSize);
 274 
 275   // find all the locals that the interpreter thinks contain live oops
 276   const ResourceBitMap live_oops = method()->live_local_oops_at_bci(osr_bci());
 277   for (index = 0; index < max_locals; index++) {
 278 
 279     if (!live_locals.at(index)) {
 280       continue;
 281     }
 282 
 283     const Type *type = osr_block->local_type_at(index);
 284 
 285     if (type->isa_oopptr() != NULL) {
 286 
 287       // 6403625: Verify that the interpreter oopMap thinks that the oop is live
 288       // else we might load a stale oop if the MethodLiveness disagrees with the
 289       // result of the interpreter. If the interpreter says it is dead we agree
 290       // by making the value go to top.
 291       //
 292 
 293       if (!live_oops.at(index)) {
 294         if (C->log() != NULL) {
 295           C->log()->elem("OSR_mismatch local_index='%d'",index);
 296         }
 297         set_local(index, null());
 298         // and ignore it for the loads
 299         continue;
 300       }
 301     }
 302 
 303     // Filter out TOP, HALF, and BOTTOM.  (Cf. ensure_phi.)
 304     if (type == Type::TOP || type == Type::HALF) {
 305       continue;
 306     }
 307     // If the type falls to bottom, then this must be a local that
 308     // is mixing ints and oops or some such.  Forcing it to top
 309     // makes it go dead.
 310     if (type == Type::BOTTOM) {
 311       continue;
 312     }
 313     // Construct code to access the appropriate local.
 314     Node* value = fetch_interpreter_state(index, type, locals_addr, osr_buf);
 315     set_local(index, value);
 316   }
 317 
 318   // Extract the needed stack entries from the interpreter frame.
 319   for (index = 0; index < sp(); index++) {
 320     const Type *type = osr_block->stack_type_at(index);
 321     if (type != Type::TOP) {
 322       // Currently the compiler bails out when attempting to on stack replace
 323       // at a bci with a non-empty stack.  We should not reach here.
 324       ShouldNotReachHere();
 325     }
 326   }
 327 
 328   // End the OSR migration
 329   make_runtime_call(RC_LEAF, OptoRuntime::osr_end_Type(),
 330                     CAST_FROM_FN_PTR(address, SharedRuntime::OSR_migration_end),
 331                     "OSR_migration_end", TypeRawPtr::BOTTOM,
 332                     osr_buf);
 333 
 334   // Now that the interpreter state is loaded, make sure it will match
 335   // at execution time what the compiler is expecting now:
 336   SafePointNode* bad_type_exit = clone_map();
 337   bad_type_exit->set_control(new RegionNode(1));
 338 
 339   assert(osr_block->flow()->jsrs()->size() == 0, "should be no jsrs live at osr point");
 340   for (index = 0; index < max_locals; index++) {
 341     if (stopped())  break;
 342     Node* l = local(index);
 343     if (l->is_top())  continue;  // nothing here
 344     const Type *type = osr_block->local_type_at(index);
 345     if (type->isa_oopptr() != NULL) {
 346       if (!live_oops.at(index)) {
 347         // skip type check for dead oops
 348         continue;
 349       }
 350     }
 351     if (osr_block->flow()->local_type_at(index)->is_return_address()) {
 352       // In our current system it's illegal for jsr addresses to be
 353       // live into an OSR entry point because the compiler performs
 354       // inlining of jsrs.  ciTypeFlow has a bailout that detect this
 355       // case and aborts the compile if addresses are live into an OSR
 356       // entry point.  Because of that we can assume that any address
 357       // locals at the OSR entry point are dead.  Method liveness
 358       // isn't precise enought to figure out that they are dead in all
 359       // cases so simply skip checking address locals all
 360       // together. Any type check is guaranteed to fail since the
 361       // interpreter type is the result of a load which might have any
 362       // value and the expected type is a constant.
 363       continue;
 364     }
 365     set_local(index, check_interpreter_type(l, type, bad_type_exit));
 366   }
 367 
 368   for (index = 0; index < sp(); index++) {
 369     if (stopped())  break;
 370     Node* l = stack(index);
 371     if (l->is_top())  continue;  // nothing here
 372     const Type *type = osr_block->stack_type_at(index);
 373     set_stack(index, check_interpreter_type(l, type, bad_type_exit));
 374   }
 375 
 376   if (bad_type_exit->control()->req() > 1) {
 377     // Build an uncommon trap here, if any inputs can be unexpected.
 378     bad_type_exit->set_control(_gvn.transform( bad_type_exit->control() ));
 379     record_for_igvn(bad_type_exit->control());
 380     SafePointNode* types_are_good = map();
 381     set_map(bad_type_exit);
 382     // The unexpected type happens because a new edge is active
 383     // in the CFG, which typeflow had previously ignored.
 384     // E.g., Object x = coldAtFirst() && notReached()? "str": new Integer(123).
 385     // This x will be typed as Integer if notReached is not yet linked.
 386     // It could also happen due to a problem in ciTypeFlow analysis.
 387     uncommon_trap(Deoptimization::Reason_constraint,
 388                   Deoptimization::Action_reinterpret);
 389     set_map(types_are_good);
 390   }
 391 }
 392 
 393 //------------------------------Parse------------------------------------------
 394 // Main parser constructor.
 395 Parse::Parse(JVMState* caller, ciMethod* parse_method, float expected_uses)
 396   : _exits(caller)
 397 {
 398   // Init some variables
 399   _caller = caller;
 400   _method = parse_method;
 401   _expected_uses = expected_uses;
 402   _depth = 1 + (caller->has_method() ? caller->depth() : 0);
 403   _wrote_final = false;
 404   _wrote_volatile = false;
 405   _wrote_stable = false;
 406   _wrote_fields = false;
 407   _alloc_with_final = NULL;
 408   _entry_bci = InvocationEntryBci;
 409   _tf = NULL;
 410   _block = NULL;
 411   _first_return = true;
 412   _replaced_nodes_for_exceptions = false;
 413   _new_idx = C->unique();
 414   debug_only(_block_count = -1);
 415   debug_only(_blocks = (Block*)-1);
 416 #ifndef PRODUCT
 417   if (PrintCompilation || PrintOpto) {
 418     // Make sure I have an inline tree, so I can print messages about it.
 419     JVMState* ilt_caller = is_osr_parse() ? caller->caller() : caller;
 420     InlineTree::find_subtree_from_root(C->ilt(), ilt_caller, parse_method);
 421   }
 422   _max_switch_depth = 0;
 423   _est_switch_depth = 0;
 424 #endif
 425 
 426   if (parse_method->has_reserved_stack_access()) {
 427     C->set_has_reserved_stack_access(true);
 428   }
 429 
 430   _tf = TypeFunc::make(method());
 431   _iter.reset_to_method(method());
 432   _flow = method()->get_flow_analysis();
 433   if (_flow->failing()) {
 434     C->record_method_not_compilable(_flow->failure_reason());
 435   }
 436 
 437 #ifndef PRODUCT
 438   if (_flow->has_irreducible_entry()) {
 439     C->set_parsed_irreducible_loop(true);
 440   }
 441 #endif
 442 
 443   if (_expected_uses <= 0) {
 444     _prof_factor = 1;
 445   } else {
 446     float prof_total = parse_method->interpreter_invocation_count();
 447     if (prof_total <= _expected_uses) {
 448       _prof_factor = 1;
 449     } else {
 450       _prof_factor = _expected_uses / prof_total;
 451     }
 452   }
 453 
 454   CompileLog* log = C->log();
 455   if (log != NULL) {
 456     log->begin_head("parse method='%d' uses='%f'",
 457                     log->identify(parse_method), expected_uses);
 458     if (depth() == 1 && C->is_osr_compilation()) {
 459       log->print(" osr_bci='%d'", C->entry_bci());
 460     }
 461     log->stamp();
 462     log->end_head();
 463   }
 464 
 465   // Accumulate deoptimization counts.
 466   // (The range_check and store_check counts are checked elsewhere.)
 467   ciMethodData* md = method()->method_data();
 468   for (uint reason = 0; reason < md->trap_reason_limit(); reason++) {
 469     uint md_count = md->trap_count(reason);
 470     if (md_count != 0) {
 471       if (md_count == md->trap_count_limit())
 472         md_count += md->overflow_trap_count();
 473       uint total_count = C->trap_count(reason);
 474       uint old_count   = total_count;
 475       total_count += md_count;
 476       // Saturate the add if it overflows.
 477       if (total_count < old_count || total_count < md_count)
 478         total_count = (uint)-1;
 479       C->set_trap_count(reason, total_count);
 480       if (log != NULL)
 481         log->elem("observe trap='%s' count='%d' total='%d'",
 482                   Deoptimization::trap_reason_name(reason),
 483                   md_count, total_count);
 484     }
 485   }
 486   // Accumulate total sum of decompilations, also.
 487   C->set_decompile_count(C->decompile_count() + md->decompile_count());
 488 
 489   _count_invocations = C->do_count_invocations();
 490   _method_data_update = C->do_method_data_update();
 491 
 492   if (log != NULL && method()->has_exception_handlers()) {
 493     log->elem("observe that='has_exception_handlers'");
 494   }
 495 
 496   assert(InlineTree::check_can_parse(method()) == NULL, "Can not parse this method, cutout earlier");
 497   assert(method()->has_balanced_monitors(), "Can not parse unbalanced monitors, cutout earlier");
 498 
 499   // Always register dependence if JVMTI is enabled, because
 500   // either breakpoint setting or hotswapping of methods may
 501   // cause deoptimization.
 502   if (C->env()->jvmti_can_hotswap_or_post_breakpoint()) {
 503     C->dependencies()->assert_evol_method(method());
 504   }
 505 
 506   NOT_PRODUCT(methods_seen++);
 507 
 508   // Do some special top-level things.
 509   if (depth() == 1 && C->is_osr_compilation()) {
 510     _entry_bci = C->entry_bci();
 511     _flow = method()->get_osr_flow_analysis(osr_bci());
 512     if (_flow->failing()) {
 513       C->record_method_not_compilable(_flow->failure_reason());
 514 #ifndef PRODUCT
 515       if (PrintOpto && (Verbose || WizardMode)) {
 516         tty->print_cr("OSR @%d type flow bailout: %s", _entry_bci, _flow->failure_reason());
 517         if (Verbose) {
 518           method()->print();
 519           method()->print_codes();
 520           _flow->print();
 521         }
 522       }
 523 #endif
 524     }
 525     _tf = C->tf();     // the OSR entry type is different
 526   }
 527 
 528 #ifdef ASSERT
 529   if (depth() == 1) {
 530     assert(C->is_osr_compilation() == this->is_osr_parse(), "OSR in sync");
 531     if (C->tf() != tf()) {
 532       MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
 533       assert(C->env()->system_dictionary_modification_counter_changed(),
 534              "Must invalidate if TypeFuncs differ");
 535     }
 536   } else {
 537     assert(!this->is_osr_parse(), "no recursive OSR");
 538   }
 539 #endif
 540 
 541 #ifndef PRODUCT
 542   methods_parsed++;
 543   // add method size here to guarantee that inlined methods are added too
 544   if (CITime)
 545     _total_bytes_compiled += method()->code_size();
 546 
 547   show_parse_info();
 548 #endif
 549 
 550   if (failing()) {
 551     if (log)  log->done("parse");
 552     return;
 553   }
 554 
 555   gvn().set_type(root(), root()->bottom_type());
 556   gvn().transform(top());
 557 
 558   // Import the results of the ciTypeFlow.
 559   init_blocks();
 560 
 561   // Merge point for all normal exits
 562   build_exits();
 563 
 564   // Setup the initial JVM state map.
 565   SafePointNode* entry_map = create_entry_map();
 566 
 567   // Check for bailouts during map initialization
 568   if (failing() || entry_map == NULL) {
 569     if (log)  log->done("parse");
 570     return;
 571   }
 572 
 573   Node_Notes* caller_nn = C->default_node_notes();
 574   // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
 575   if (DebugInlinedCalls || depth() == 1) {
 576     C->set_default_node_notes(make_node_notes(caller_nn));
 577   }
 578 
 579   if (is_osr_parse()) {
 580     Node* osr_buf = entry_map->in(TypeFunc::Parms+0);
 581     entry_map->set_req(TypeFunc::Parms+0, top());
 582     set_map(entry_map);
 583     load_interpreter_state(osr_buf);
 584   } else {
 585     set_map(entry_map);
 586     do_method_entry();
 587     if (depth() == 1 && C->age_code()) {
 588       decrement_age();
 589     }
 590   }
 591 
 592   if (depth() == 1 && !failing()) {
 593     // Add check to deoptimize the nmethod if RTM state was changed
 594     rtm_deopt();
 595   }
 596 
 597   // Check for bailouts during method entry or RTM state check setup.
 598   if (failing()) {
 599     if (log)  log->done("parse");
 600     C->set_default_node_notes(caller_nn);
 601     return;
 602   }
 603 
 604   // Handle value type arguments
 605   int arg_size_sig = tf()->domain_sig()->cnt();
 606   for (uint i = 0; i < (uint)arg_size_sig; i++) {
 607     Node* parm = map()->in(i);
 608     const Type* t = _gvn.type(parm);
 609     if (!ValueTypePassFieldsAsArgs) {
 610       if (t->is_valuetypeptr()) {
 611         // Create ValueTypeNode from the oop and replace the parameter
 612         assert(!t->is_ptr()->maybe_null(), "value type arguments should never be null");
 613         Node* vt = ValueTypeNode::make_from_oop(this, parm, t->value_klass(), /* buffer_check */ true, /* null2default */ false);
 614         map()->replace_edge(parm, vt);
 615       }
 616     } else {
 617       assert(false, "FIXME");
 618       // TODO move the code from build_start_state and do_late_inline here
 619     }
 620   }
 621 
 622   entry_map = map();  // capture any changes performed by method setup code
 623   assert(jvms()->endoff() == map()->req(), "map matches JVMS layout");
 624 
 625   // We begin parsing as if we have just encountered a jump to the
 626   // method entry.
 627   Block* entry_block = start_block();
 628   assert(entry_block->start() == (is_osr_parse() ? osr_bci() : 0), "");
 629   set_map_clone(entry_map);
 630   merge_common(entry_block, entry_block->next_path_num());
 631 
 632 #ifndef PRODUCT
 633   BytecodeParseHistogram *parse_histogram_obj = new (C->env()->arena()) BytecodeParseHistogram(this, C);
 634   set_parse_histogram( parse_histogram_obj );
 635 #endif
 636 
 637   // Parse all the basic blocks.
 638   do_all_blocks();
 639 
 640   C->set_default_node_notes(caller_nn);
 641 
 642   // Check for bailouts during conversion to graph
 643   if (failing()) {
 644     if (log)  log->done("parse");
 645     return;
 646   }
 647 
 648   // Fix up all exiting control flow.
 649   set_map(entry_map);
 650   do_exits();
 651 
 652   if (log)  log->done("parse nodes='%d' live='%d' memory='" SIZE_FORMAT "'",
 653                       C->unique(), C->live_nodes(), C->node_arena()->used());
 654 }
 655 
 656 //---------------------------do_all_blocks-------------------------------------
 657 void Parse::do_all_blocks() {
 658   bool has_irreducible = flow()->has_irreducible_entry();
 659 
 660   // Walk over all blocks in Reverse Post-Order.
 661   while (true) {
 662     bool progress = false;
 663     for (int rpo = 0; rpo < block_count(); rpo++) {
 664       Block* block = rpo_at(rpo);
 665 
 666       if (block->is_parsed()) continue;
 667 
 668       if (!block->is_merged()) {
 669         // Dead block, no state reaches this block
 670         continue;
 671       }
 672 
 673       // Prepare to parse this block.
 674       load_state_from(block);
 675 
 676       if (stopped()) {
 677         // Block is dead.
 678         continue;
 679       }
 680 
 681       NOT_PRODUCT(blocks_parsed++);
 682 
 683       progress = true;
 684       if (block->is_loop_head() || block->is_handler() || (has_irreducible && !block->is_ready())) {
 685         // Not all preds have been parsed.  We must build phis everywhere.
 686         // (Note that dead locals do not get phis built, ever.)
 687         ensure_phis_everywhere();
 688 
 689         if (block->is_SEL_head()) {
 690           // Add predicate to single entry (not irreducible) loop head.
 691           assert(!block->has_merged_backedge(), "only entry paths should be merged for now");
 692           // Predicates may have been added after a dominating if
 693           if (!block->has_predicates()) {
 694             // Need correct bci for predicate.
 695             // It is fine to set it here since do_one_block() will set it anyway.
 696             set_parse_bci(block->start());
 697             add_predicate();
 698           }
 699           // Add new region for back branches.
 700           int edges = block->pred_count() - block->preds_parsed() + 1; // +1 for original region
 701           RegionNode *r = new RegionNode(edges+1);
 702           _gvn.set_type(r, Type::CONTROL);
 703           record_for_igvn(r);
 704           r->init_req(edges, control());
 705           set_control(r);
 706           // Add new phis.
 707           ensure_phis_everywhere();
 708         }
 709 
 710         // Leave behind an undisturbed copy of the map, for future merges.
 711         set_map(clone_map());
 712       }
 713 
 714       if (control()->is_Region() && !block->is_loop_head() && !has_irreducible && !block->is_handler()) {
 715         // In the absence of irreducible loops, the Region and Phis
 716         // associated with a merge that doesn't involve a backedge can
 717         // be simplified now since the RPO parsing order guarantees
 718         // that any path which was supposed to reach here has already
 719         // been parsed or must be dead.
 720         Node* c = control();
 721         Node* result = _gvn.transform_no_reclaim(control());
 722         if (c != result && TraceOptoParse) {
 723           tty->print_cr("Block #%d replace %d with %d", block->rpo(), c->_idx, result->_idx);
 724         }
 725         if (result != top()) {
 726           record_for_igvn(result);
 727         }
 728       }
 729 
 730       // Parse the block.
 731       do_one_block();
 732 
 733       // Check for bailouts.
 734       if (failing())  return;
 735     }
 736 
 737     // with irreducible loops multiple passes might be necessary to parse everything
 738     if (!has_irreducible || !progress) {
 739       break;
 740     }
 741   }
 742 
 743 #ifndef PRODUCT
 744   blocks_seen += block_count();
 745 
 746   // Make sure there are no half-processed blocks remaining.
 747   // Every remaining unprocessed block is dead and may be ignored now.
 748   for (int rpo = 0; rpo < block_count(); rpo++) {
 749     Block* block = rpo_at(rpo);
 750     if (!block->is_parsed()) {
 751       if (TraceOptoParse) {
 752         tty->print_cr("Skipped dead block %d at bci:%d", rpo, block->start());
 753       }
 754       assert(!block->is_merged(), "no half-processed blocks");
 755     }
 756   }
 757 #endif
 758 }
 759 
 760 static Node* mask_int_value(Node* v, BasicType bt, PhaseGVN* gvn) {
 761   switch (bt) {
 762   case T_BYTE:
 763     v = gvn->transform(new LShiftINode(v, gvn->intcon(24)));
 764     v = gvn->transform(new RShiftINode(v, gvn->intcon(24)));
 765     break;
 766   case T_SHORT:
 767     v = gvn->transform(new LShiftINode(v, gvn->intcon(16)));
 768     v = gvn->transform(new RShiftINode(v, gvn->intcon(16)));
 769     break;
 770   case T_CHAR:
 771     v = gvn->transform(new AndINode(v, gvn->intcon(0xFFFF)));
 772     break;
 773   case T_BOOLEAN:
 774     v = gvn->transform(new AndINode(v, gvn->intcon(0x1)));
 775     break;
 776   default:
 777     break;
 778   }
 779   return v;
 780 }
 781 
 782 //-------------------------------build_exits----------------------------------
 783 // Build normal and exceptional exit merge points.
 784 void Parse::build_exits() {
 785   // make a clone of caller to prevent sharing of side-effects
 786   _exits.set_map(_exits.clone_map());
 787   _exits.clean_stack(_exits.sp());
 788   _exits.sync_jvms();
 789 
 790   RegionNode* region = new RegionNode(1);
 791   record_for_igvn(region);
 792   gvn().set_type_bottom(region);
 793   _exits.set_control(region);
 794 
 795   // Note:  iophi and memphi are not transformed until do_exits.
 796   Node* iophi  = new PhiNode(region, Type::ABIO);
 797   Node* memphi = new PhiNode(region, Type::MEMORY, TypePtr::BOTTOM);
 798   gvn().set_type_bottom(iophi);
 799   gvn().set_type_bottom(memphi);
 800   _exits.set_i_o(iophi);
 801   _exits.set_all_memory(memphi);
 802 
 803   // Add a return value to the exit state.  (Do not push it yet.)
 804   if (tf()->range_sig()->cnt() > TypeFunc::Parms) {
 805     const Type* ret_type = tf()->range_sig()->field_at(TypeFunc::Parms);
 806     if (ret_type->isa_int()) {
 807       BasicType ret_bt = method()->return_type()->basic_type();
 808       if (ret_bt == T_BOOLEAN ||
 809           ret_bt == T_CHAR ||
 810           ret_bt == T_BYTE ||
 811           ret_bt == T_SHORT) {
 812         ret_type = TypeInt::INT;
 813       }
 814     }
 815 
 816     // Don't "bind" an unloaded return klass to the ret_phi. If the klass
 817     // becomes loaded during the subsequent parsing, the loaded and unloaded
 818     // types will not join when we transform and push in do_exits().
 819     const TypeOopPtr* ret_oop_type = ret_type->isa_oopptr();
 820     if (ret_oop_type && !ret_oop_type->klass()->is_loaded()) {
 821       ret_type = TypeOopPtr::BOTTOM;
 822     }
 823     if ((_caller->has_method() || tf()->returns_value_type_as_fields()) && ret_type->is_valuetypeptr()) {
 824       // When inlining or with multiple return values: return value
 825       // type as ValueTypeNode not as oop
 826       ret_type = TypeValueType::make(ret_type->value_klass());
 827     }
 828     int         ret_size = type2size[ret_type->basic_type()];
 829     Node*       ret_phi  = new PhiNode(region, ret_type);
 830     gvn().set_type_bottom(ret_phi);
 831     _exits.ensure_stack(ret_size);
 832     assert((int)(tf()->range_sig()->cnt() - TypeFunc::Parms) == ret_size, "good tf range");
 833     assert(method()->return_type()->size() == ret_size, "tf agrees w/ method");
 834     _exits.set_argument(0, ret_phi);  // here is where the parser finds it
 835     // Note:  ret_phi is not yet pushed, until do_exits.
 836   }
 837 }
 838 
 839 //----------------------------build_start_state-------------------------------
 840 // Construct a state which contains only the incoming arguments from an
 841 // unknown caller.  The method & bci will be NULL & InvocationEntryBci.
 842 JVMState* Compile::build_start_state(StartNode* start, const TypeFunc* tf) {
 843   int        arg_size_sig = tf->domain_sig()->cnt();
 844   int        max_size = MAX2(arg_size_sig, (int)tf->range_cc()->cnt());
 845   JVMState*  jvms     = new (this) JVMState(max_size - TypeFunc::Parms);
 846   SafePointNode* map  = new SafePointNode(max_size, NULL);
 847   record_for_igvn(map);
 848   assert(arg_size_sig == TypeFunc::Parms + (is_osr_compilation() ? 1 : method()->arg_size()), "correct arg_size");
 849   Node_Notes* old_nn = default_node_notes();
 850   if (old_nn != NULL && has_method()) {
 851     Node_Notes* entry_nn = old_nn->clone(this);
 852     JVMState* entry_jvms = new(this) JVMState(method(), old_nn->jvms());
 853     entry_jvms->set_offsets(0);
 854     entry_jvms->set_bci(entry_bci());
 855     entry_nn->set_jvms(entry_jvms);
 856     set_default_node_notes(entry_nn);
 857   }
 858   PhaseGVN& gvn = *initial_gvn();
 859   uint j = 0;
 860   for (uint i = 0; i < (uint)arg_size_sig; i++) {
 861     assert(j >= i, "less actual arguments than in the signature?");
 862     if (ValueTypePassFieldsAsArgs) {
 863       assert(false, "FIXME");
 864       // TODO move this into Parse::Parse because we might need to deopt
 865       /*
 866       if (i < TypeFunc::Parms) {
 867         assert(i == j, "no change before the actual arguments");
 868         Node* parm = gvn.transform(new ParmNode(start, i));
 869         map->init_req(i, parm);
 870         // Record all these guys for later GVN.
 871         record_for_igvn(parm);
 872         j++;
 873       } else {
 874         // Value type arguments are not passed by reference: we get an
 875         // argument per field of the value type. Build ValueTypeNodes
 876         // from the value type arguments.
 877         const Type* t = tf->domain_sig()->field_at(i);
 878         if (t->is_valuetypeptr()) {
 879           ciValueKlass* vk = t->value_klass();
 880           GraphKit kit(jvms, &gvn);
 881           kit.set_control(map->control());
 882           ValueTypeNode* vt = ValueTypeNode::make_from_multi(&kit, start, vk, j, true);
 883           map->set_control(kit.control());
 884           map->init_req(i, vt);
 885           j += vk->value_arg_slots();
 886         } else {
 887           Node* parm = gvn.transform(new ParmNode(start, j));
 888           map->init_req(i, parm);
 889           // Record all these guys for later GVN.
 890           record_for_igvn(parm);
 891           j++;
 892         }
 893       }
 894       */
 895     } else {
 896       Node* parm = gvn.transform(new ParmNode(start, i));
 897       map->init_req(i, parm);
 898       // Record all these guys for later GVN.
 899       record_for_igvn(parm);
 900       j++;
 901     }
 902   }
 903   for (; j < map->req(); j++) {
 904     map->init_req(j, top());
 905   }
 906   assert(jvms->argoff() == TypeFunc::Parms, "parser gets arguments here");
 907   set_default_node_notes(old_nn);
 908   map->set_jvms(jvms);
 909   jvms->set_map(map);
 910   return jvms;
 911 }
 912 
 913 //-----------------------------make_node_notes---------------------------------
 914 Node_Notes* Parse::make_node_notes(Node_Notes* caller_nn) {
 915   if (caller_nn == NULL)  return NULL;
 916   Node_Notes* nn = caller_nn->clone(C);
 917   JVMState* caller_jvms = nn->jvms();
 918   JVMState* jvms = new (C) JVMState(method(), caller_jvms);
 919   jvms->set_offsets(0);
 920   jvms->set_bci(_entry_bci);
 921   nn->set_jvms(jvms);
 922   return nn;
 923 }
 924 
 925 
 926 //--------------------------return_values--------------------------------------
 927 void Compile::return_values(JVMState* jvms) {
 928   GraphKit kit(jvms);
 929   Node* ret = new ReturnNode(TypeFunc::Parms,
 930                              kit.control(),
 931                              kit.i_o(),
 932                              kit.reset_memory(),
 933                              kit.frameptr(),
 934                              kit.returnadr());
 935   // Add zero or 1 return values
 936   int ret_size = tf()->range_sig()->cnt() - TypeFunc::Parms;
 937   if (ret_size > 0) {
 938     kit.inc_sp(-ret_size);  // pop the return value(s)
 939     kit.sync_jvms();
 940     Node* res = kit.argument(0);
 941     if (tf()->returns_value_type_as_fields()) {
 942       // Multiple return values (value type fields): add as many edges
 943       // to the Return node as returned values.
 944       assert(res->is_ValueType(), "what else supports multi value return");
 945       ValueTypeNode* vt = res->as_ValueType();
 946       ret->add_req_batch(NULL, tf()->range_cc()->cnt() - TypeFunc::Parms);
 947       vt->pass_klass(ret, TypeFunc::Parms, kit);
 948       vt->pass_fields(ret, TypeFunc::Parms+1, kit, /* assert_allocated */ true);
 949     } else {
 950       ret->add_req(res);
 951       // Note:  The second dummy edge is not needed by a ReturnNode.
 952     }
 953   }
 954   // bind it to root
 955   root()->add_req(ret);
 956   record_for_igvn(ret);
 957   initial_gvn()->transform_no_reclaim(ret);
 958 }
 959 
 960 //------------------------rethrow_exceptions-----------------------------------
 961 // Bind all exception states in the list into a single RethrowNode.
 962 void Compile::rethrow_exceptions(JVMState* jvms) {
 963   GraphKit kit(jvms);
 964   if (!kit.has_exceptions())  return;  // nothing to generate
 965   // Load my combined exception state into the kit, with all phis transformed:
 966   SafePointNode* ex_map = kit.combine_and_pop_all_exception_states();
 967   Node* ex_oop = kit.use_exception_state(ex_map);
 968   RethrowNode* exit = new RethrowNode(kit.control(),
 969                                       kit.i_o(), kit.reset_memory(),
 970                                       kit.frameptr(), kit.returnadr(),
 971                                       // like a return but with exception input
 972                                       ex_oop);
 973   // bind to root
 974   root()->add_req(exit);
 975   record_for_igvn(exit);
 976   initial_gvn()->transform_no_reclaim(exit);
 977 }
 978 
 979 //---------------------------do_exceptions-------------------------------------
 980 // Process exceptions arising from the current bytecode.
 981 // Send caught exceptions to the proper handler within this method.
 982 // Unhandled exceptions feed into _exit.
 983 void Parse::do_exceptions() {
 984   if (!has_exceptions())  return;
 985 
 986   if (failing()) {
 987     // Pop them all off and throw them away.
 988     while (pop_exception_state() != NULL) ;
 989     return;
 990   }
 991 
 992   PreserveJVMState pjvms(this, false);
 993 
 994   SafePointNode* ex_map;
 995   while ((ex_map = pop_exception_state()) != NULL) {
 996     if (!method()->has_exception_handlers()) {
 997       // Common case:  Transfer control outward.
 998       // Doing it this early allows the exceptions to common up
 999       // even between adjacent method calls.
1000       throw_to_exit(ex_map);
1001     } else {
1002       // Have to look at the exception first.
1003       assert(stopped(), "catch_inline_exceptions trashes the map");
1004       catch_inline_exceptions(ex_map);
1005       stop_and_kill_map();      // we used up this exception state; kill it
1006     }
1007   }
1008 
1009   // We now return to our regularly scheduled program:
1010 }
1011 
1012 //---------------------------throw_to_exit-------------------------------------
1013 // Merge the given map into an exception exit from this method.
1014 // The exception exit will handle any unlocking of receiver.
1015 // The ex_oop must be saved within the ex_map, unlike merge_exception.
1016 void Parse::throw_to_exit(SafePointNode* ex_map) {
1017   // Pop the JVMS to (a copy of) the caller.
1018   GraphKit caller;
1019   caller.set_map_clone(_caller->map());
1020   caller.set_bci(_caller->bci());
1021   caller.set_sp(_caller->sp());
1022   // Copy out the standard machine state:
1023   for (uint i = 0; i < TypeFunc::Parms; i++) {
1024     caller.map()->set_req(i, ex_map->in(i));
1025   }
1026   if (ex_map->has_replaced_nodes()) {
1027     _replaced_nodes_for_exceptions = true;
1028   }
1029   caller.map()->transfer_replaced_nodes_from(ex_map, _new_idx);
1030   // ...and the exception:
1031   Node*          ex_oop        = saved_ex_oop(ex_map);
1032   SafePointNode* caller_ex_map = caller.make_exception_state(ex_oop);
1033   // Finally, collect the new exception state in my exits:
1034   _exits.add_exception_state(caller_ex_map);
1035 }
1036 
1037 //------------------------------do_exits---------------------------------------
1038 void Parse::do_exits() {
1039   set_parse_bci(InvocationEntryBci);
1040 
1041   // Now peephole on the return bits
1042   Node* region = _exits.control();
1043   _exits.set_control(gvn().transform(region));
1044 
1045   Node* iophi = _exits.i_o();
1046   _exits.set_i_o(gvn().transform(iophi));
1047 
1048   // Figure out if we need to emit the trailing barrier. The barrier is only
1049   // needed in the constructors, and only in three cases:
1050   //
1051   // 1. The constructor wrote a final. The effects of all initializations
1052   //    must be committed to memory before any code after the constructor
1053   //    publishes the reference to the newly constructed object. Rather
1054   //    than wait for the publication, we simply block the writes here.
1055   //    Rather than put a barrier on only those writes which are required
1056   //    to complete, we force all writes to complete.
1057   //
1058   // 2. On PPC64, also add MemBarRelease for constructors which write
1059   //    volatile fields. As support_IRIW_for_not_multiple_copy_atomic_cpu
1060   //    is set on PPC64, no sync instruction is issued after volatile
1061   //    stores. We want to guarantee the same behavior as on platforms
1062   //    with total store order, although this is not required by the Java
1063   //    memory model. So as with finals, we add a barrier here.
1064   //
1065   // 3. Experimental VM option is used to force the barrier if any field
1066   //    was written out in the constructor.
1067   //
1068   // "All bets are off" unless the first publication occurs after a
1069   // normal return from the constructor.  We do not attempt to detect
1070   // such unusual early publications.  But no barrier is needed on
1071   // exceptional returns, since they cannot publish normally.
1072   //
1073   if (method()->is_initializer() &&
1074         (wrote_final() ||
1075            PPC64_ONLY(wrote_volatile() ||)
1076            (AlwaysSafeConstructors && wrote_fields()))) {
1077     _exits.insert_mem_bar(Op_MemBarRelease, alloc_with_final());
1078 
1079     // If Memory barrier is created for final fields write
1080     // and allocation node does not escape the initialize method,
1081     // then barrier introduced by allocation node can be removed.
1082     if (DoEscapeAnalysis && alloc_with_final()) {
1083       AllocateNode *alloc = AllocateNode::Ideal_allocation(alloc_with_final(), &_gvn);
1084       alloc->compute_MemBar_redundancy(method());
1085     }
1086     if (PrintOpto && (Verbose || WizardMode)) {
1087       method()->print_name();
1088       tty->print_cr(" writes finals and needs a memory barrier");
1089     }
1090   }
1091 
1092   // Any method can write a @Stable field; insert memory barriers
1093   // after those also. Can't bind predecessor allocation node (if any)
1094   // with barrier because allocation doesn't always dominate
1095   // MemBarRelease.
1096   if (wrote_stable()) {
1097     _exits.insert_mem_bar(Op_MemBarRelease);
1098     if (PrintOpto && (Verbose || WizardMode)) {
1099       method()->print_name();
1100       tty->print_cr(" writes @Stable and needs a memory barrier");
1101     }
1102   }
1103 
1104   for (MergeMemStream mms(_exits.merged_memory()); mms.next_non_empty(); ) {
1105     // transform each slice of the original memphi:
1106     mms.set_memory(_gvn.transform(mms.memory()));
1107   }
1108 
1109   if (tf()->range_sig()->cnt() > TypeFunc::Parms) {
1110     const Type* ret_type = tf()->range_sig()->field_at(TypeFunc::Parms);
1111     Node*       ret_phi  = _gvn.transform( _exits.argument(0) );
1112     if (!_exits.control()->is_top() && _gvn.type(ret_phi)->empty()) {
1113       // In case of concurrent class loading, the type we set for the
1114       // ret_phi in build_exits() may have been too optimistic and the
1115       // ret_phi may be top now.
1116       // Otherwise, we've encountered an error and have to mark the method as
1117       // not compilable. Just using an assertion instead would be dangerous
1118       // as this could lead to an infinite compile loop in non-debug builds.
1119       {
1120         MutexLockerEx ml(Compile_lock, Mutex::_no_safepoint_check_flag);
1121         if (C->env()->system_dictionary_modification_counter_changed()) {
1122           C->record_failure(C2Compiler::retry_class_loading_during_parsing());
1123         } else {
1124           C->record_method_not_compilable("Can't determine return type.");
1125         }
1126       }
1127       return;
1128     }
1129     if (ret_type->isa_int()) {
1130       BasicType ret_bt = method()->return_type()->basic_type();
1131       ret_phi = mask_int_value(ret_phi, ret_bt, &_gvn);
1132     }
1133     if (_caller->has_method() && ret_type->is_valuetypeptr()) {
1134       // Inlined methods return a ValueTypeNode
1135       _exits.push_node(T_VALUETYPE, ret_phi);
1136     } else {
1137       _exits.push_node(ret_type->basic_type(), ret_phi);
1138     }
1139   }
1140 
1141   // Note:  Logic for creating and optimizing the ReturnNode is in Compile.
1142 
1143   // Unlock along the exceptional paths.
1144   // This is done late so that we can common up equivalent exceptions
1145   // (e.g., null checks) arising from multiple points within this method.
1146   // See GraphKit::add_exception_state, which performs the commoning.
1147   bool do_synch = method()->is_synchronized() && GenerateSynchronizationCode;
1148 
1149   // record exit from a method if compiled while Dtrace is turned on.
1150   if (do_synch || C->env()->dtrace_method_probes() || _replaced_nodes_for_exceptions) {
1151     // First move the exception list out of _exits:
1152     GraphKit kit(_exits.transfer_exceptions_into_jvms());
1153     SafePointNode* normal_map = kit.map();  // keep this guy safe
1154     // Now re-collect the exceptions into _exits:
1155     SafePointNode* ex_map;
1156     while ((ex_map = kit.pop_exception_state()) != NULL) {
1157       Node* ex_oop = kit.use_exception_state(ex_map);
1158       // Force the exiting JVM state to have this method at InvocationEntryBci.
1159       // The exiting JVM state is otherwise a copy of the calling JVMS.
1160       JVMState* caller = kit.jvms();
1161       JVMState* ex_jvms = caller->clone_shallow(C);
1162       ex_jvms->set_map(kit.clone_map());
1163       ex_jvms->map()->set_jvms(ex_jvms);
1164       ex_jvms->set_bci(   InvocationEntryBci);
1165       kit.set_jvms(ex_jvms);
1166       if (do_synch) {
1167         // Add on the synchronized-method box/object combo
1168         kit.map()->push_monitor(_synch_lock);
1169         // Unlock!
1170         kit.shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
1171       }
1172       if (C->env()->dtrace_method_probes()) {
1173         kit.make_dtrace_method_exit(method());
1174       }
1175       if (_replaced_nodes_for_exceptions) {
1176         kit.map()->apply_replaced_nodes(_new_idx);
1177       }
1178       // Done with exception-path processing.
1179       ex_map = kit.make_exception_state(ex_oop);
1180       assert(ex_jvms->same_calls_as(ex_map->jvms()), "sanity");
1181       // Pop the last vestige of this method:
1182       ex_map->set_jvms(caller->clone_shallow(C));
1183       ex_map->jvms()->set_map(ex_map);
1184       _exits.push_exception_state(ex_map);
1185     }
1186     assert(_exits.map() == normal_map, "keep the same return state");
1187   }
1188 
1189   {
1190     // Capture very early exceptions (receiver null checks) from caller JVMS
1191     GraphKit caller(_caller);
1192     SafePointNode* ex_map;
1193     while ((ex_map = caller.pop_exception_state()) != NULL) {
1194       _exits.add_exception_state(ex_map);
1195     }
1196   }
1197   _exits.map()->apply_replaced_nodes(_new_idx);
1198 }
1199 
1200 //-----------------------------create_entry_map-------------------------------
1201 // Initialize our parser map to contain the types at method entry.
1202 // For OSR, the map contains a single RawPtr parameter.
1203 // Initial monitor locking for sync. methods is performed by do_method_entry.
1204 SafePointNode* Parse::create_entry_map() {
1205   // Check for really stupid bail-out cases.
1206   uint len = TypeFunc::Parms + method()->max_locals() + method()->max_stack();
1207   if (len >= 32760) {
1208     C->record_method_not_compilable("too many local variables");
1209     return NULL;
1210   }
1211 
1212   // clear current replaced nodes that are of no use from here on (map was cloned in build_exits).
1213   _caller->map()->delete_replaced_nodes();
1214 
1215   // If this is an inlined method, we may have to do a receiver null check.
1216   if (_caller->has_method() && is_normal_parse() && !method()->is_static()) {
1217     GraphKit kit(_caller);
1218     if (!kit.argument(0)->is_ValueType()) {
1219       kit.null_check_receiver_before_call(method());
1220     }
1221     _caller = kit.transfer_exceptions_into_jvms();
1222     if (kit.stopped()) {
1223       _exits.add_exception_states_from(_caller);
1224       _exits.set_jvms(_caller);
1225       return NULL;
1226     }
1227   }
1228 
1229   assert(method() != NULL, "parser must have a method");
1230 
1231   // Create an initial safepoint to hold JVM state during parsing
1232   JVMState* jvms = new (C) JVMState(method(), _caller->has_method() ? _caller : NULL);
1233   set_map(new SafePointNode(len, jvms));
1234   jvms->set_map(map());
1235   record_for_igvn(map());
1236   assert(jvms->endoff() == len, "correct jvms sizing");
1237 
1238   SafePointNode* inmap = _caller->map();
1239   assert(inmap != NULL, "must have inmap");
1240   // In case of null check on receiver above
1241   map()->transfer_replaced_nodes_from(inmap, _new_idx);
1242 
1243   uint i;
1244 
1245   // Pass thru the predefined input parameters.
1246   for (i = 0; i < TypeFunc::Parms; i++) {
1247     map()->init_req(i, inmap->in(i));
1248   }
1249 
1250   if (depth() == 1) {
1251     assert(map()->memory()->Opcode() == Op_Parm, "");
1252     // Insert the memory aliasing node
1253     set_all_memory(reset_memory());
1254   }
1255   assert(merged_memory(), "");
1256 
1257   // Now add the locals which are initially bound to arguments:
1258   uint arg_size = tf()->domain_sig()->cnt();
1259   ensure_stack(arg_size - TypeFunc::Parms);  // OSR methods have funny args
1260   for (i = TypeFunc::Parms; i < arg_size; i++) {
1261     map()->init_req(i, inmap->argument(_caller, i - TypeFunc::Parms));
1262   }
1263 
1264   // Clear out the rest of the map (locals and stack)
1265   for (i = arg_size; i < len; i++) {
1266     map()->init_req(i, top());
1267   }
1268 
1269   SafePointNode* entry_map = stop();
1270   return entry_map;
1271 }
1272 
1273 //-----------------------------do_method_entry--------------------------------
1274 // Emit any code needed in the pseudo-block before BCI zero.
1275 // The main thing to do is lock the receiver of a synchronized method.
1276 void Parse::do_method_entry() {
1277   set_parse_bci(InvocationEntryBci); // Pseudo-BCP
1278   set_sp(0);                      // Java Stack Pointer
1279 
1280   NOT_PRODUCT( count_compiled_calls(true/*at_method_entry*/, false/*is_inline*/); )
1281 
1282   if (C->env()->dtrace_method_probes()) {
1283     make_dtrace_method_entry(method());
1284   }
1285 
1286   // If the method is synchronized, we need to construct a lock node, attach
1287   // it to the Start node, and pin it there.
1288   if (method()->is_synchronized()) {
1289     // Insert a FastLockNode right after the Start which takes as arguments
1290     // the current thread pointer, the "this" pointer & the address of the
1291     // stack slot pair used for the lock.  The "this" pointer is a projection
1292     // off the start node, but the locking spot has to be constructed by
1293     // creating a ConLNode of 0, and boxing it with a BoxLockNode.  The BoxLockNode
1294     // becomes the second argument to the FastLockNode call.  The
1295     // FastLockNode becomes the new control parent to pin it to the start.
1296 
1297     // Setup Object Pointer
1298     Node *lock_obj = NULL;
1299     if(method()->is_static()) {
1300       ciInstance* mirror = _method->holder()->java_mirror();
1301       const TypeInstPtr *t_lock = TypeInstPtr::make(mirror);
1302       lock_obj = makecon(t_lock);
1303     } else {                  // Else pass the "this" pointer,
1304       lock_obj = local(0);    // which is Parm0 from StartNode
1305     }
1306     // Clear out dead values from the debug info.
1307     kill_dead_locals();
1308     // Build the FastLockNode
1309     _synch_lock = shared_lock(lock_obj);
1310   }
1311 
1312   // Feed profiling data for parameters to the type system so it can
1313   // propagate it as speculative types
1314   record_profiled_parameters_for_speculation();
1315 
1316   if (depth() == 1) {
1317     increment_and_test_invocation_counter(Tier2CompileThreshold);
1318   }
1319 }
1320 
1321 //------------------------------init_blocks------------------------------------
1322 // Initialize our parser map to contain the types/monitors at method entry.
1323 void Parse::init_blocks() {
1324   // Create the blocks.
1325   _block_count = flow()->block_count();
1326   _blocks = NEW_RESOURCE_ARRAY(Block, _block_count);
1327 
1328   // Initialize the structs.
1329   for (int rpo = 0; rpo < block_count(); rpo++) {
1330     Block* block = rpo_at(rpo);
1331     new(block) Block(this, rpo);
1332   }
1333 
1334   // Collect predecessor and successor information.
1335   for (int rpo = 0; rpo < block_count(); rpo++) {
1336     Block* block = rpo_at(rpo);
1337     block->init_graph(this);
1338   }
1339 }
1340 
1341 //-------------------------------init_node-------------------------------------
1342 Parse::Block::Block(Parse* outer, int rpo) : _live_locals() {
1343   _flow = outer->flow()->rpo_at(rpo);
1344   _pred_count = 0;
1345   _preds_parsed = 0;
1346   _count = 0;
1347   _is_parsed = false;
1348   _is_handler = false;
1349   _has_merged_backedge = false;
1350   _start_map = NULL;
1351   _has_predicates = false;
1352   _num_successors = 0;
1353   _all_successors = 0;
1354   _successors = NULL;
1355   assert(pred_count() == 0 && preds_parsed() == 0, "sanity");
1356   assert(!(is_merged() || is_parsed() || is_handler() || has_merged_backedge()), "sanity");
1357   assert(_live_locals.size() == 0, "sanity");
1358 
1359   // entry point has additional predecessor
1360   if (flow()->is_start())  _pred_count++;
1361   assert(flow()->is_start() == (this == outer->start_block()), "");
1362 }
1363 
1364 //-------------------------------init_graph------------------------------------
1365 void Parse::Block::init_graph(Parse* outer) {
1366   // Create the successor list for this parser block.
1367   GrowableArray<ciTypeFlow::Block*>* tfs = flow()->successors();
1368   GrowableArray<ciTypeFlow::Block*>* tfe = flow()->exceptions();
1369   int ns = tfs->length();
1370   int ne = tfe->length();
1371   _num_successors = ns;
1372   _all_successors = ns+ne;
1373   _successors = (ns+ne == 0) ? NULL : NEW_RESOURCE_ARRAY(Block*, ns+ne);
1374   int p = 0;
1375   for (int i = 0; i < ns+ne; i++) {
1376     ciTypeFlow::Block* tf2 = (i < ns) ? tfs->at(i) : tfe->at(i-ns);
1377     Block* block2 = outer->rpo_at(tf2->rpo());
1378     _successors[i] = block2;
1379 
1380     // Accumulate pred info for the other block, too.
1381     if (i < ns) {
1382       block2->_pred_count++;
1383     } else {
1384       block2->_is_handler = true;
1385     }
1386 
1387     #ifdef ASSERT
1388     // A block's successors must be distinguishable by BCI.
1389     // That is, no bytecode is allowed to branch to two different
1390     // clones of the same code location.
1391     for (int j = 0; j < i; j++) {
1392       Block* block1 = _successors[j];
1393       if (block1 == block2)  continue;  // duplicates are OK
1394       assert(block1->start() != block2->start(), "successors have unique bcis");
1395     }
1396     #endif
1397   }
1398 
1399   // Note: We never call next_path_num along exception paths, so they
1400   // never get processed as "ready".  Also, the input phis of exception
1401   // handlers get specially processed, so that
1402 }
1403 
1404 //---------------------------successor_for_bci---------------------------------
1405 Parse::Block* Parse::Block::successor_for_bci(int bci) {
1406   for (int i = 0; i < all_successors(); i++) {
1407     Block* block2 = successor_at(i);
1408     if (block2->start() == bci)  return block2;
1409   }
1410   // We can actually reach here if ciTypeFlow traps out a block
1411   // due to an unloaded class, and concurrently with compilation the
1412   // class is then loaded, so that a later phase of the parser is
1413   // able to see more of the bytecode CFG.  Or, the flow pass and
1414   // the parser can have a minor difference of opinion about executability
1415   // of bytecodes.  For example, "obj.field = null" is executable even
1416   // if the field's type is an unloaded class; the flow pass used to
1417   // make a trap for such code.
1418   return NULL;
1419 }
1420 
1421 
1422 //-----------------------------stack_type_at-----------------------------------
1423 const Type* Parse::Block::stack_type_at(int i) const {
1424   return get_type(flow()->stack_type_at(i));
1425 }
1426 
1427 
1428 //-----------------------------local_type_at-----------------------------------
1429 const Type* Parse::Block::local_type_at(int i) const {
1430   // Make dead locals fall to bottom.
1431   if (_live_locals.size() == 0) {
1432     MethodLivenessResult live_locals = flow()->outer()->method()->liveness_at_bci(start());
1433     // This bitmap can be zero length if we saw a breakpoint.
1434     // In such cases, pretend they are all live.
1435     ((Block*)this)->_live_locals = live_locals;
1436   }
1437   if (_live_locals.size() > 0 && !_live_locals.at(i))
1438     return Type::BOTTOM;
1439 
1440   return get_type(flow()->local_type_at(i));
1441 }
1442 
1443 
1444 #ifndef PRODUCT
1445 
1446 //----------------------------name_for_bc--------------------------------------
1447 // helper method for BytecodeParseHistogram
1448 static const char* name_for_bc(int i) {
1449   return Bytecodes::is_defined(i) ? Bytecodes::name(Bytecodes::cast(i)) : "xxxunusedxxx";
1450 }
1451 
1452 //----------------------------BytecodeParseHistogram------------------------------------
1453 Parse::BytecodeParseHistogram::BytecodeParseHistogram(Parse *p, Compile *c) {
1454   _parser   = p;
1455   _compiler = c;
1456   if( ! _initialized ) { _initialized = true; reset(); }
1457 }
1458 
1459 //----------------------------current_count------------------------------------
1460 int Parse::BytecodeParseHistogram::current_count(BPHType bph_type) {
1461   switch( bph_type ) {
1462   case BPH_transforms: { return _parser->gvn().made_progress(); }
1463   case BPH_values:     { return _parser->gvn().made_new_values(); }
1464   default: { ShouldNotReachHere(); return 0; }
1465   }
1466 }
1467 
1468 //----------------------------initialized--------------------------------------
1469 bool Parse::BytecodeParseHistogram::initialized() { return _initialized; }
1470 
1471 //----------------------------reset--------------------------------------------
1472 void Parse::BytecodeParseHistogram::reset() {
1473   int i = Bytecodes::number_of_codes;
1474   while (i-- > 0) { _bytecodes_parsed[i] = 0; _nodes_constructed[i] = 0; _nodes_transformed[i] = 0; _new_values[i] = 0; }
1475 }
1476 
1477 //----------------------------set_initial_state--------------------------------
1478 // Record info when starting to parse one bytecode
1479 void Parse::BytecodeParseHistogram::set_initial_state( Bytecodes::Code bc ) {
1480   if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1481     _initial_bytecode    = bc;
1482     _initial_node_count  = _compiler->unique();
1483     _initial_transforms  = current_count(BPH_transforms);
1484     _initial_values      = current_count(BPH_values);
1485   }
1486 }
1487 
1488 //----------------------------record_change--------------------------------
1489 // Record results of parsing one bytecode
1490 void Parse::BytecodeParseHistogram::record_change() {
1491   if( PrintParseStatistics && !_parser->is_osr_parse() ) {
1492     ++_bytecodes_parsed[_initial_bytecode];
1493     _nodes_constructed [_initial_bytecode] += (_compiler->unique() - _initial_node_count);
1494     _nodes_transformed [_initial_bytecode] += (current_count(BPH_transforms) - _initial_transforms);
1495     _new_values        [_initial_bytecode] += (current_count(BPH_values)     - _initial_values);
1496   }
1497 }
1498 
1499 
1500 //----------------------------print--------------------------------------------
1501 void Parse::BytecodeParseHistogram::print(float cutoff) {
1502   ResourceMark rm;
1503   // print profile
1504   int total  = 0;
1505   int i      = 0;
1506   for( i = 0; i < Bytecodes::number_of_codes; ++i ) { total += _bytecodes_parsed[i]; }
1507   int abs_sum = 0;
1508   tty->cr();   //0123456789012345678901234567890123456789012345678901234567890123456789
1509   tty->print_cr("Histogram of %d parsed bytecodes:", total);
1510   if( total == 0 ) { return; }
1511   tty->cr();
1512   tty->print_cr("absolute:  count of compiled bytecodes of this type");
1513   tty->print_cr("relative:  percentage contribution to compiled nodes");
1514   tty->print_cr("nodes   :  Average number of nodes constructed per bytecode");
1515   tty->print_cr("rnodes  :  Significance towards total nodes constructed, (nodes*relative)");
1516   tty->print_cr("transforms: Average amount of tranform progress per bytecode compiled");
1517   tty->print_cr("values  :  Average number of node values improved per bytecode");
1518   tty->print_cr("name    :  Bytecode name");
1519   tty->cr();
1520   tty->print_cr("  absolute  relative   nodes  rnodes  transforms  values   name");
1521   tty->print_cr("----------------------------------------------------------------------");
1522   while (--i > 0) {
1523     int       abs = _bytecodes_parsed[i];
1524     float     rel = abs * 100.0F / total;
1525     float   nodes = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_constructed[i])/_bytecodes_parsed[i];
1526     float  rnodes = _bytecodes_parsed[i] == 0 ? 0 :  rel * nodes;
1527     float  xforms = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _nodes_transformed[i])/_bytecodes_parsed[i];
1528     float  values = _bytecodes_parsed[i] == 0 ? 0 : (1.0F * _new_values       [i])/_bytecodes_parsed[i];
1529     if (cutoff <= rel) {
1530       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));
1531       abs_sum += abs;
1532     }
1533   }
1534   tty->print_cr("----------------------------------------------------------------------");
1535   float rel_sum = abs_sum * 100.0F / total;
1536   tty->print_cr("%10d  %7.2f%%    (cutoff = %.2f%%)", abs_sum, rel_sum, cutoff);
1537   tty->print_cr("----------------------------------------------------------------------");
1538   tty->cr();
1539 }
1540 #endif
1541 
1542 //----------------------------load_state_from----------------------------------
1543 // Load block/map/sp.  But not do not touch iter/bci.
1544 void Parse::load_state_from(Block* block) {
1545   set_block(block);
1546   // load the block's JVM state:
1547   set_map(block->start_map());
1548   set_sp( block->start_sp());
1549 }
1550 
1551 
1552 //-----------------------------record_state------------------------------------
1553 void Parse::Block::record_state(Parse* p) {
1554   assert(!is_merged(), "can only record state once, on 1st inflow");
1555   assert(start_sp() == p->sp(), "stack pointer must agree with ciTypeFlow");
1556   set_start_map(p->stop());
1557 }
1558 
1559 
1560 //------------------------------do_one_block-----------------------------------
1561 void Parse::do_one_block() {
1562   if (TraceOptoParse) {
1563     Block *b = block();
1564     int ns = b->num_successors();
1565     int nt = b->all_successors();
1566 
1567     tty->print("Parsing block #%d at bci [%d,%d), successors: ",
1568                   block()->rpo(), block()->start(), block()->limit());
1569     for (int i = 0; i < nt; i++) {
1570       tty->print((( i < ns) ? " %d" : " %d(e)"), b->successor_at(i)->rpo());
1571     }
1572     if (b->is_loop_head()) tty->print("  lphd");
1573     tty->cr();
1574   }
1575 
1576   assert(block()->is_merged(), "must be merged before being parsed");
1577   block()->mark_parsed();
1578 
1579   // Set iterator to start of block.
1580   iter().reset_to_bci(block()->start());
1581 
1582   CompileLog* log = C->log();
1583 
1584   // Parse bytecodes
1585   while (!stopped() && !failing()) {
1586     iter().next();
1587 
1588     // Learn the current bci from the iterator:
1589     set_parse_bci(iter().cur_bci());
1590 
1591     if (bci() == block()->limit()) {
1592       // Do not walk into the next block until directed by do_all_blocks.
1593       merge(bci());
1594       break;
1595     }
1596     assert(bci() < block()->limit(), "bci still in block");
1597 
1598     if (log != NULL) {
1599       // Output an optional context marker, to help place actions
1600       // that occur during parsing of this BC.  If there is no log
1601       // output until the next context string, this context string
1602       // will be silently ignored.
1603       log->set_context("bc code='%d' bci='%d'", (int)bc(), bci());
1604     }
1605 
1606     if (block()->has_trap_at(bci())) {
1607       // We must respect the flow pass's traps, because it will refuse
1608       // to produce successors for trapping blocks.
1609       int trap_index = block()->flow()->trap_index();
1610       assert(trap_index != 0, "trap index must be valid");
1611       uncommon_trap(trap_index);
1612       break;
1613     }
1614 
1615     NOT_PRODUCT( parse_histogram()->set_initial_state(bc()); );
1616 
1617 #ifdef ASSERT
1618     int pre_bc_sp = sp();
1619     int inputs, depth;
1620     bool have_se = !stopped() && compute_stack_effects(inputs, depth);
1621     assert(!have_se || pre_bc_sp >= inputs, "have enough stack to execute this BC: pre_bc_sp=%d, inputs=%d", pre_bc_sp, inputs);
1622 #endif //ASSERT
1623 
1624     do_one_bytecode();
1625 
1626     assert(!have_se || stopped() || failing() || (sp() - pre_bc_sp) == depth,
1627            "incorrect depth prediction: sp=%d, pre_bc_sp=%d, depth=%d", sp(), pre_bc_sp, depth);
1628 
1629     do_exceptions();
1630 
1631     NOT_PRODUCT( parse_histogram()->record_change(); );
1632 
1633     if (log != NULL)
1634       log->clear_context();  // skip marker if nothing was printed
1635 
1636     // Fall into next bytecode.  Each bytecode normally has 1 sequential
1637     // successor which is typically made ready by visiting this bytecode.
1638     // If the successor has several predecessors, then it is a merge
1639     // point, starts a new basic block, and is handled like other basic blocks.
1640   }
1641 }
1642 
1643 
1644 //------------------------------merge------------------------------------------
1645 void Parse::set_parse_bci(int bci) {
1646   set_bci(bci);
1647   Node_Notes* nn = C->default_node_notes();
1648   if (nn == NULL)  return;
1649 
1650   // Collect debug info for inlined calls unless -XX:-DebugInlinedCalls.
1651   if (!DebugInlinedCalls && depth() > 1) {
1652     return;
1653   }
1654 
1655   // Update the JVMS annotation, if present.
1656   JVMState* jvms = nn->jvms();
1657   if (jvms != NULL && jvms->bci() != bci) {
1658     // Update the JVMS.
1659     jvms = jvms->clone_shallow(C);
1660     jvms->set_bci(bci);
1661     nn->set_jvms(jvms);
1662   }
1663 }
1664 
1665 //------------------------------merge------------------------------------------
1666 // Merge the current mapping into the basic block starting at bci
1667 void Parse::merge(int target_bci) {
1668   Block* target = successor_for_bci(target_bci);
1669   if (target == NULL) { handle_missing_successor(target_bci); return; }
1670   assert(!target->is_ready(), "our arrival must be expected");
1671   int pnum = target->next_path_num();
1672   merge_common(target, pnum);
1673 }
1674 
1675 //-------------------------merge_new_path--------------------------------------
1676 // Merge the current mapping into the basic block, using a new path
1677 void Parse::merge_new_path(int target_bci) {
1678   Block* target = successor_for_bci(target_bci);
1679   if (target == NULL) { handle_missing_successor(target_bci); return; }
1680   assert(!target->is_ready(), "new path into frozen graph");
1681   int pnum = target->add_new_path();
1682   merge_common(target, pnum);
1683 }
1684 
1685 //-------------------------merge_exception-------------------------------------
1686 // Merge the current mapping into the basic block starting at bci
1687 // The ex_oop must be pushed on the stack, unlike throw_to_exit.
1688 void Parse::merge_exception(int target_bci) {
1689   assert(sp() == 1, "must have only the throw exception on the stack");
1690   Block* target = successor_for_bci(target_bci);
1691   if (target == NULL) { handle_missing_successor(target_bci); return; }
1692   assert(target->is_handler(), "exceptions are handled by special blocks");
1693   int pnum = target->add_new_path();
1694   merge_common(target, pnum);
1695 }
1696 
1697 //--------------------handle_missing_successor---------------------------------
1698 void Parse::handle_missing_successor(int target_bci) {
1699 #ifndef PRODUCT
1700   Block* b = block();
1701   int trap_bci = b->flow()->has_trap()? b->flow()->trap_bci(): -1;
1702   tty->print_cr("### Missing successor at bci:%d for block #%d (trap_bci:%d)", target_bci, b->rpo(), trap_bci);
1703 #endif
1704   ShouldNotReachHere();
1705 }
1706 
1707 //--------------------------merge_common---------------------------------------
1708 void Parse::merge_common(Parse::Block* target, int pnum) {
1709   if (TraceOptoParse) {
1710     tty->print("Merging state at block #%d bci:%d", target->rpo(), target->start());
1711   }
1712 
1713   // Zap extra stack slots to top
1714   assert(sp() == target->start_sp(), "");
1715   clean_stack(sp());
1716 
1717   // Check for merge conflicts involving value types
1718   JVMState* old_jvms = map()->jvms();
1719   int old_bci = bci();
1720   JVMState* tmp_jvms = old_jvms->clone_shallow(C);
1721   tmp_jvms->set_should_reexecute(true);
1722   map()->set_jvms(tmp_jvms);
1723   // Execution needs to restart a the next bytecode (entry of next
1724   // block)
1725   if (target->is_merged() ||
1726       pnum > PhiNode::Input ||
1727       target->is_handler() ||
1728       target->is_loop_head()) {
1729     set_parse_bci(target->start());
1730     for (uint j = TypeFunc::Parms; j < map()->req(); j++) {
1731       Node* n = map()->in(j);                 // Incoming change to target state.
1732       const Type* t = NULL;
1733       if (tmp_jvms->is_loc(j)) {
1734         t = target->local_type_at(j - tmp_jvms->locoff());
1735       } else if (tmp_jvms->is_stk(j) && j < (uint)sp() + tmp_jvms->stkoff()) {
1736         t = target->stack_type_at(j - tmp_jvms->stkoff());
1737       }
1738       if (t != NULL && t != Type::BOTTOM) {
1739         if (n->is_ValueType() && !t->isa_valuetype()) {
1740           // Allocate value type in src block to be able to merge it with oop in target block
1741           ValueTypeBaseNode* vt = n->as_ValueType()->allocate(this, true);
1742           map()->set_req(j, ValueTypePtrNode::make_from_value_type(_gvn, vt->as_ValueType()));
1743         }
1744         if (t->isa_valuetype() && !n->is_ValueType()) {
1745           // check for a null constant
1746           assert(n->bottom_type()->remove_speculative() == TypePtr::NULL_PTR, "Anything other than null?");
1747           uncommon_trap(Deoptimization::Reason_null_check, Deoptimization::Action_none);
1748           assert(stopped(), "should be a dead path now");
1749           set_parse_bci(old_bci);
1750           return;
1751         }
1752       }
1753     }
1754   }
1755   map()->set_jvms(old_jvms);
1756   set_parse_bci(old_bci);
1757 
1758   if (!target->is_merged()) {   // No prior mapping at this bci
1759     if (TraceOptoParse) { tty->print(" with empty state");  }
1760 
1761     // If this path is dead, do not bother capturing it as a merge.
1762     // It is "as if" we had 1 fewer predecessors from the beginning.
1763     if (stopped()) {
1764       if (TraceOptoParse)  tty->print_cr(", but path is dead and doesn't count");
1765       return;
1766     }
1767 
1768     // Make a region if we know there are multiple or unpredictable inputs.
1769     // (Also, if this is a plain fall-through, we might see another region,
1770     // which must not be allowed into this block's map.)
1771     if (pnum > PhiNode::Input         // Known multiple inputs.
1772         || target->is_handler()       // These have unpredictable inputs.
1773         || target->is_loop_head()     // Known multiple inputs
1774         || control()->is_Region()) {  // We must hide this guy.
1775 
1776       int current_bci = bci();
1777       set_parse_bci(target->start()); // Set target bci
1778       if (target->is_SEL_head()) {
1779         DEBUG_ONLY( target->mark_merged_backedge(block()); )
1780         if (target->start() == 0) {
1781           // Add loop predicate for the special case when
1782           // there are backbranches to the method entry.
1783           add_predicate();
1784         }
1785       }
1786       // Add a Region to start the new basic block.  Phis will be added
1787       // later lazily.
1788       int edges = target->pred_count();
1789       if (edges < pnum)  edges = pnum;  // might be a new path!
1790       RegionNode *r = new RegionNode(edges+1);
1791       gvn().set_type(r, Type::CONTROL);
1792       record_for_igvn(r);
1793       // zap all inputs to NULL for debugging (done in Node(uint) constructor)
1794       // for (int j = 1; j < edges+1; j++) { r->init_req(j, NULL); }
1795       r->init_req(pnum, control());
1796       set_control(r);
1797       set_parse_bci(current_bci); // Restore bci
1798     }
1799 
1800     // Convert the existing Parser mapping into a mapping at this bci.
1801     store_state_to(target);
1802     assert(target->is_merged(), "do not come here twice");
1803 
1804   } else {                      // Prior mapping at this bci
1805     if (TraceOptoParse) {  tty->print(" with previous state"); }
1806 #ifdef ASSERT
1807     if (target->is_SEL_head()) {
1808       target->mark_merged_backedge(block());
1809     }
1810 #endif
1811 
1812     // We must not manufacture more phis if the target is already parsed.
1813     bool nophi = target->is_parsed();
1814 
1815     SafePointNode* newin = map();// Hang on to incoming mapping
1816     Block* save_block = block(); // Hang on to incoming block;
1817     load_state_from(target);    // Get prior mapping
1818 
1819     assert(newin->jvms()->locoff() == jvms()->locoff(), "JVMS layouts agree");
1820     assert(newin->jvms()->stkoff() == jvms()->stkoff(), "JVMS layouts agree");
1821     assert(newin->jvms()->monoff() == jvms()->monoff(), "JVMS layouts agree");
1822     assert(newin->jvms()->endoff() == jvms()->endoff(), "JVMS layouts agree");
1823 
1824     // Iterate over my current mapping and the old mapping.
1825     // Where different, insert Phi functions.
1826     // Use any existing Phi functions.
1827     assert(control()->is_Region(), "must be merging to a region");
1828     RegionNode* r = control()->as_Region();
1829 
1830     // Compute where to merge into
1831     // Merge incoming control path
1832     r->init_req(pnum, newin->control());
1833 
1834     if (pnum == 1) {            // Last merge for this Region?
1835       if (!block()->flow()->is_irreducible_entry()) {
1836         Node* result = _gvn.transform_no_reclaim(r);
1837         if (r != result && TraceOptoParse) {
1838           tty->print_cr("Block #%d replace %d with %d", block()->rpo(), r->_idx, result->_idx);
1839         }
1840       }
1841       record_for_igvn(r);
1842     }
1843 
1844     // Update all the non-control inputs to map:
1845     assert(TypeFunc::Parms == newin->jvms()->locoff(), "parser map should contain only youngest jvms");
1846     bool check_elide_phi = target->is_SEL_backedge(save_block);
1847     bool last_merge = (pnum == PhiNode::Input);
1848     for (uint j = 1; j < newin->req(); j++) {
1849       Node* m = map()->in(j);   // Current state of target.
1850       Node* n = newin->in(j);   // Incoming change to target state.
1851       PhiNode* phi;
1852       if (m->is_Phi() && m->as_Phi()->region() == r) {
1853         phi = m->as_Phi();
1854       } else if (m->is_ValueType() && m->as_ValueType()->has_phi_inputs(r)){
1855         phi = m->as_ValueType()->get_oop()->as_Phi();
1856       } else {
1857         phi = NULL;
1858       }
1859       if (m != n) {             // Different; must merge
1860         switch (j) {
1861         // Frame pointer and Return Address never changes
1862         case TypeFunc::FramePtr:// Drop m, use the original value
1863         case TypeFunc::ReturnAdr:
1864           break;
1865         case TypeFunc::Memory:  // Merge inputs to the MergeMem node
1866           assert(phi == NULL, "the merge contains phis, not vice versa");
1867           merge_memory_edges(n->as_MergeMem(), pnum, nophi);
1868           continue;
1869         default:                // All normal stuff
1870           if (phi == NULL) {
1871             const JVMState* jvms = map()->jvms();
1872             if (EliminateNestedLocks &&
1873                 jvms->is_mon(j) && jvms->is_monitor_box(j)) {
1874               // BoxLock nodes are not commoning.
1875               // Use old BoxLock node as merged box.
1876               assert(newin->jvms()->is_monitor_box(j), "sanity");
1877               // This assert also tests that nodes are BoxLock.
1878               assert(BoxLockNode::same_slot(n, m), "sanity");
1879               C->gvn_replace_by(n, m);
1880             } else if (!check_elide_phi || !target->can_elide_SEL_phi(j)) {
1881               phi = ensure_phi(j, nophi);
1882             }
1883           }
1884           break;
1885         }
1886       }
1887       // At this point, n might be top if:
1888       //  - there is no phi (because TypeFlow detected a conflict), or
1889       //  - the corresponding control edges is top (a dead incoming path)
1890       // It is a bug if we create a phi which sees a garbage value on a live path.
1891 
1892       // Merging two value types?
1893       if (phi != NULL && n->isa_ValueType()) {
1894         // Reload current state because it may have been updated by ensure_phi
1895         m = map()->in(j);
1896         ValueTypeNode* vtm = m->as_ValueType(); // Current value type
1897         ValueTypeNode* vtn = n->as_ValueType(); // Incoming value type
1898         assert(vtm->get_oop() == phi, "Value type should have Phi input");
1899         if (TraceOptoParse) {
1900 #ifdef ASSERT
1901           tty->print_cr("\nMerging value types");
1902           tty->print_cr("Current:");
1903           vtm->dump(2);
1904           tty->print_cr("Incoming:");
1905           vtn->dump(2);
1906           tty->cr();
1907 #endif
1908         }
1909         // Do the merge
1910         vtm->merge_with(&_gvn, vtn, pnum, last_merge);
1911         if (last_merge) {
1912           map()->set_req(j, _gvn.transform_no_reclaim(vtm));
1913           record_for_igvn(vtm);
1914         }
1915       } else if (phi != NULL) {
1916         assert(n != top() || r->in(pnum) == top(), "live value must not be garbage");
1917         assert(phi->region() == r, "");
1918         phi->set_req(pnum, n);  // Then add 'n' to the merge
1919         if (last_merge) {
1920           // Last merge for this Phi.
1921           // So far, Phis have had a reasonable type from ciTypeFlow.
1922           // Now _gvn will join that with the meet of current inputs.
1923           // BOTTOM is never permissible here, 'cause pessimistically
1924           // Phis of pointers cannot lose the basic pointer type.
1925           debug_only(const Type* bt1 = phi->bottom_type());
1926           assert(bt1 != Type::BOTTOM, "should not be building conflict phis");
1927           map()->set_req(j, _gvn.transform_no_reclaim(phi));
1928           debug_only(const Type* bt2 = phi->bottom_type());
1929           assert(bt2->higher_equal_speculative(bt1), "must be consistent with type-flow");
1930           record_for_igvn(phi);
1931         }
1932       }
1933     } // End of for all values to be merged
1934 
1935     if (last_merge && !r->in(0)) {         // The occasional useless Region
1936       assert(control() == r, "");
1937       set_control(r->nonnull_req());
1938     }
1939 
1940     map()->merge_replaced_nodes_with(newin);
1941 
1942     // newin has been subsumed into the lazy merge, and is now dead.
1943     set_block(save_block);
1944 
1945     stop();                     // done with this guy, for now
1946   }
1947 
1948   if (TraceOptoParse) {
1949     tty->print_cr(" on path %d", pnum);
1950   }
1951 
1952   // Done with this parser state.
1953   assert(stopped(), "");
1954 }
1955 
1956 
1957 //--------------------------merge_memory_edges---------------------------------
1958 void Parse::merge_memory_edges(MergeMemNode* n, int pnum, bool nophi) {
1959   // (nophi means we must not create phis, because we already parsed here)
1960   assert(n != NULL, "");
1961   // Merge the inputs to the MergeMems
1962   MergeMemNode* m = merged_memory();
1963 
1964   assert(control()->is_Region(), "must be merging to a region");
1965   RegionNode* r = control()->as_Region();
1966 
1967   PhiNode* base = NULL;
1968   MergeMemNode* remerge = NULL;
1969   for (MergeMemStream mms(m, n); mms.next_non_empty2(); ) {
1970     Node *p = mms.force_memory();
1971     Node *q = mms.memory2();
1972     if (mms.is_empty() && nophi) {
1973       // Trouble:  No new splits allowed after a loop body is parsed.
1974       // Instead, wire the new split into a MergeMem on the backedge.
1975       // The optimizer will sort it out, slicing the phi.
1976       if (remerge == NULL) {
1977         guarantee(base != NULL, "");
1978         assert(base->in(0) != NULL, "should not be xformed away");
1979         remerge = MergeMemNode::make(base->in(pnum));
1980         gvn().set_type(remerge, Type::MEMORY);
1981         base->set_req(pnum, remerge);
1982       }
1983       remerge->set_memory_at(mms.alias_idx(), q);
1984       continue;
1985     }
1986     assert(!q->is_MergeMem(), "");
1987     PhiNode* phi;
1988     if (p != q) {
1989       phi = ensure_memory_phi(mms.alias_idx(), nophi);
1990     } else {
1991       if (p->is_Phi() && p->as_Phi()->region() == r)
1992         phi = p->as_Phi();
1993       else
1994         phi = NULL;
1995     }
1996     // Insert q into local phi
1997     if (phi != NULL) {
1998       assert(phi->region() == r, "");
1999       p = phi;
2000       phi->set_req(pnum, q);
2001       if (mms.at_base_memory()) {
2002         base = phi;  // delay transforming it
2003       } else if (pnum == 1) {
2004         record_for_igvn(phi);
2005         p = _gvn.transform_no_reclaim(phi);
2006       }
2007       mms.set_memory(p);// store back through the iterator
2008     }
2009   }
2010   // Transform base last, in case we must fiddle with remerging.
2011   if (base != NULL && pnum == 1) {
2012     record_for_igvn(base);
2013     m->set_base_memory( _gvn.transform_no_reclaim(base) );
2014   }
2015 }
2016 
2017 
2018 //------------------------ensure_phis_everywhere-------------------------------
2019 void Parse::ensure_phis_everywhere() {
2020   ensure_phi(TypeFunc::I_O);
2021 
2022   // Ensure a phi on all currently known memories.
2023   for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
2024     ensure_memory_phi(mms.alias_idx());
2025     debug_only(mms.set_memory());  // keep the iterator happy
2026   }
2027 
2028   // Note:  This is our only chance to create phis for memory slices.
2029   // If we miss a slice that crops up later, it will have to be
2030   // merged into the base-memory phi that we are building here.
2031   // Later, the optimizer will comb out the knot, and build separate
2032   // phi-loops for each memory slice that matters.
2033 
2034   // Monitors must nest nicely and not get confused amongst themselves.
2035   // Phi-ify everything up to the monitors, though.
2036   uint monoff = map()->jvms()->monoff();
2037   uint nof_monitors = map()->jvms()->nof_monitors();
2038 
2039   assert(TypeFunc::Parms == map()->jvms()->locoff(), "parser map should contain only youngest jvms");
2040   bool check_elide_phi = block()->is_SEL_head();
2041   for (uint i = TypeFunc::Parms; i < monoff; i++) {
2042     if (!check_elide_phi || !block()->can_elide_SEL_phi(i)) {
2043       ensure_phi(i);
2044     }
2045   }
2046 
2047   // Even monitors need Phis, though they are well-structured.
2048   // This is true for OSR methods, and also for the rare cases where
2049   // a monitor object is the subject of a replace_in_map operation.
2050   // See bugs 4426707 and 5043395.
2051   for (uint m = 0; m < nof_monitors; m++) {
2052     ensure_phi(map()->jvms()->monitor_obj_offset(m));
2053   }
2054 }
2055 
2056 
2057 //-----------------------------add_new_path------------------------------------
2058 // Add a previously unaccounted predecessor to this block.
2059 int Parse::Block::add_new_path() {
2060   // If there is no map, return the lowest unused path number.
2061   if (!is_merged())  return pred_count()+1;  // there will be a map shortly
2062 
2063   SafePointNode* map = start_map();
2064   if (!map->control()->is_Region())
2065     return pred_count()+1;  // there may be a region some day
2066   RegionNode* r = map->control()->as_Region();
2067 
2068   // Add new path to the region.
2069   uint pnum = r->req();
2070   r->add_req(NULL);
2071 
2072   for (uint i = 1; i < map->req(); i++) {
2073     Node* n = map->in(i);
2074     if (i == TypeFunc::Memory) {
2075       // Ensure a phi on all currently known memories.
2076       for (MergeMemStream mms(n->as_MergeMem()); mms.next_non_empty(); ) {
2077         Node* phi = mms.memory();
2078         if (phi->is_Phi() && phi->as_Phi()->region() == r) {
2079           assert(phi->req() == pnum, "must be same size as region");
2080           phi->add_req(NULL);
2081         }
2082       }
2083     } else {
2084       if (n->is_Phi() && n->as_Phi()->region() == r) {
2085         assert(n->req() == pnum, "must be same size as region");
2086         n->add_req(NULL);
2087       } else if (n->is_ValueType() && n->as_ValueType()->has_phi_inputs(r)) {
2088         n->as_ValueType()->add_new_path(r);
2089       }
2090     }
2091   }
2092 
2093   return pnum;
2094 }
2095 
2096 //------------------------------ensure_phi-------------------------------------
2097 // Turn the idx'th entry of the current map into a Phi
2098 PhiNode *Parse::ensure_phi(int idx, bool nocreate) {
2099   SafePointNode* map = this->map();
2100   Node* region = map->control();
2101   assert(region->is_Region(), "");
2102 
2103   Node* o = map->in(idx);
2104   assert(o != NULL, "");
2105 
2106   if (o == top())  return NULL; // TOP always merges into TOP
2107 
2108   if (o->is_Phi() && o->as_Phi()->region() == region) {
2109     return o->as_Phi();
2110   }
2111   ValueTypeBaseNode* vt = o->isa_ValueType();
2112   if (vt != NULL && vt->has_phi_inputs(region)) {
2113     return vt->get_oop()->as_Phi();
2114   }
2115 
2116   // Now use a Phi here for merging
2117   assert(!nocreate, "Cannot build a phi for a block already parsed.");
2118   const JVMState* jvms = map->jvms();
2119   const Type* t = NULL;
2120   if (jvms->is_loc(idx)) {
2121     t = block()->local_type_at(idx - jvms->locoff());
2122   } else if (jvms->is_stk(idx)) {
2123     t = block()->stack_type_at(idx - jvms->stkoff());
2124   } else if (jvms->is_mon(idx)) {
2125     assert(!jvms->is_monitor_box(idx), "no phis for boxes");
2126     t = TypeInstPtr::BOTTOM; // this is sufficient for a lock object
2127   } else if ((uint)idx < TypeFunc::Parms) {
2128     t = o->bottom_type();  // Type::RETURN_ADDRESS or such-like.
2129   } else {
2130     assert(false, "no type information for this phi");
2131   }
2132 
2133   // If the type falls to bottom, then this must be a local that
2134   // is already dead or is mixing ints and oops or some such.
2135   // Forcing it to top makes it go dead.
2136   if (t == Type::BOTTOM) {
2137     map->set_req(idx, top());
2138     return NULL;
2139   }
2140 
2141   // Do not create phis for top either.
2142   // A top on a non-null control flow must be an unused even after the.phi.
2143   if (t == Type::TOP || t == Type::HALF) {
2144     map->set_req(idx, top());
2145     return NULL;
2146   }
2147 
2148   if (vt != NULL) {
2149     // Value types are merged by merging their field values.
2150     // Create a cloned ValueTypeNode with phi inputs that
2151     // represents the merged value type and update the map.
2152     vt = vt->clone_with_phis(&_gvn, region);
2153     map->set_req(idx, vt);
2154     return vt->get_oop()->as_Phi();
2155   } else {
2156     PhiNode* phi = PhiNode::make(region, o, t);
2157     gvn().set_type(phi, t);
2158     if (C->do_escape_analysis()) record_for_igvn(phi);
2159     map->set_req(idx, phi);
2160     return phi;
2161   }
2162 }
2163 
2164 //--------------------------ensure_memory_phi----------------------------------
2165 // Turn the idx'th slice of the current memory into a Phi
2166 PhiNode *Parse::ensure_memory_phi(int idx, bool nocreate) {
2167   MergeMemNode* mem = merged_memory();
2168   Node* region = control();
2169   assert(region->is_Region(), "");
2170 
2171   Node *o = (idx == Compile::AliasIdxBot)? mem->base_memory(): mem->memory_at(idx);
2172   assert(o != NULL && o != top(), "");
2173 
2174   PhiNode* phi;
2175   if (o->is_Phi() && o->as_Phi()->region() == region) {
2176     phi = o->as_Phi();
2177     if (phi == mem->base_memory() && idx >= Compile::AliasIdxRaw) {
2178       // clone the shared base memory phi to make a new memory split
2179       assert(!nocreate, "Cannot build a phi for a block already parsed.");
2180       const Type* t = phi->bottom_type();
2181       const TypePtr* adr_type = C->get_adr_type(idx);
2182       phi = phi->slice_memory(adr_type);
2183       gvn().set_type(phi, t);
2184     }
2185     return phi;
2186   }
2187 
2188   // Now use a Phi here for merging
2189   assert(!nocreate, "Cannot build a phi for a block already parsed.");
2190   const Type* t = o->bottom_type();
2191   const TypePtr* adr_type = C->get_adr_type(idx);
2192   phi = PhiNode::make(region, o, t, adr_type);
2193   gvn().set_type(phi, t);
2194   if (idx == Compile::AliasIdxBot)
2195     mem->set_base_memory(phi);
2196   else
2197     mem->set_memory_at(idx, phi);
2198   return phi;
2199 }
2200 
2201 //------------------------------call_register_finalizer-----------------------
2202 // Check the klass of the receiver and call register_finalizer if the
2203 // class need finalization.
2204 void Parse::call_register_finalizer() {
2205   Node* receiver = local(0);
2206   assert(receiver != NULL && receiver->bottom_type()->isa_instptr() != NULL,
2207          "must have non-null instance type");
2208 
2209   const TypeInstPtr *tinst = receiver->bottom_type()->isa_instptr();
2210   if (tinst != NULL && tinst->klass()->is_loaded() && !tinst->klass_is_exact()) {
2211     // The type isn't known exactly so see if CHA tells us anything.
2212     ciInstanceKlass* ik = tinst->klass()->as_instance_klass();
2213     if (!Dependencies::has_finalizable_subclass(ik)) {
2214       // No finalizable subclasses so skip the dynamic check.
2215       C->dependencies()->assert_has_no_finalizable_subclasses(ik);
2216       return;
2217     }
2218   }
2219 
2220   // Insert a dynamic test for whether the instance needs
2221   // finalization.  In general this will fold up since the concrete
2222   // class is often visible so the access flags are constant.
2223   Node* klass_addr = basic_plus_adr( receiver, receiver, oopDesc::klass_offset_in_bytes() );
2224   Node* klass = _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), klass_addr, TypeInstPtr::KLASS));
2225 
2226   Node* access_flags_addr = basic_plus_adr(klass, klass, in_bytes(Klass::access_flags_offset()));
2227   Node* access_flags = make_load(NULL, access_flags_addr, TypeInt::INT, T_INT, MemNode::unordered);
2228 
2229   Node* mask  = _gvn.transform(new AndINode(access_flags, intcon(JVM_ACC_HAS_FINALIZER)));
2230   Node* check = _gvn.transform(new CmpINode(mask, intcon(0)));
2231   Node* test  = _gvn.transform(new BoolNode(check, BoolTest::ne));
2232 
2233   IfNode* iff = create_and_map_if(control(), test, PROB_MAX, COUNT_UNKNOWN);
2234 
2235   RegionNode* result_rgn = new RegionNode(3);
2236   record_for_igvn(result_rgn);
2237 
2238   Node *skip_register = _gvn.transform(new IfFalseNode(iff));
2239   result_rgn->init_req(1, skip_register);
2240 
2241   Node *needs_register = _gvn.transform(new IfTrueNode(iff));
2242   set_control(needs_register);
2243   if (stopped()) {
2244     // There is no slow path.
2245     result_rgn->init_req(2, top());
2246   } else {
2247     Node *call = make_runtime_call(RC_NO_LEAF,
2248                                    OptoRuntime::register_finalizer_Type(),
2249                                    OptoRuntime::register_finalizer_Java(),
2250                                    NULL, TypePtr::BOTTOM,
2251                                    receiver);
2252     make_slow_call_ex(call, env()->Throwable_klass(), true);
2253 
2254     Node* fast_io  = call->in(TypeFunc::I_O);
2255     Node* fast_mem = call->in(TypeFunc::Memory);
2256     // These two phis are pre-filled with copies of of the fast IO and Memory
2257     Node* io_phi   = PhiNode::make(result_rgn, fast_io,  Type::ABIO);
2258     Node* mem_phi  = PhiNode::make(result_rgn, fast_mem, Type::MEMORY, TypePtr::BOTTOM);
2259 
2260     result_rgn->init_req(2, control());
2261     io_phi    ->init_req(2, i_o());
2262     mem_phi   ->init_req(2, reset_memory());
2263 
2264     set_all_memory( _gvn.transform(mem_phi) );
2265     set_i_o(        _gvn.transform(io_phi) );
2266   }
2267 
2268   set_control( _gvn.transform(result_rgn) );
2269 }
2270 
2271 // Add check to deoptimize if RTM state is not ProfileRTM
2272 void Parse::rtm_deopt() {
2273 #if INCLUDE_RTM_OPT
2274   if (C->profile_rtm()) {
2275     assert(C->method() != NULL, "only for normal compilations");
2276     assert(!C->method()->method_data()->is_empty(), "MDO is needed to record RTM state");
2277     assert(depth() == 1, "generate check only for main compiled method");
2278 
2279     // Set starting bci for uncommon trap.
2280     set_parse_bci(is_osr_parse() ? osr_bci() : 0);
2281 
2282     // Load the rtm_state from the MethodData.
2283     const TypePtr* adr_type = TypeMetadataPtr::make(C->method()->method_data());
2284     Node* mdo = makecon(adr_type);
2285     int offset = MethodData::rtm_state_offset_in_bytes();
2286     Node* adr_node = basic_plus_adr(mdo, mdo, offset);
2287     Node* rtm_state = make_load(control(), adr_node, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
2288 
2289     // Separate Load from Cmp by Opaque.
2290     // In expand_macro_nodes() it will be replaced either
2291     // with this load when there are locks in the code
2292     // or with ProfileRTM (cmp->in(2)) otherwise so that
2293     // the check will fold.
2294     Node* profile_state = makecon(TypeInt::make(ProfileRTM));
2295     Node* opq   = _gvn.transform( new Opaque3Node(C, rtm_state, Opaque3Node::RTM_OPT) );
2296     Node* chk   = _gvn.transform( new CmpINode(opq, profile_state) );
2297     Node* tst   = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
2298     // Branch to failure if state was changed
2299     { BuildCutout unless(this, tst, PROB_ALWAYS);
2300       uncommon_trap(Deoptimization::Reason_rtm_state_change,
2301                     Deoptimization::Action_make_not_entrant);
2302     }
2303   }
2304 #endif
2305 }
2306 
2307 void Parse::decrement_age() {
2308   MethodCounters* mc = method()->ensure_method_counters();
2309   if (mc == NULL) {
2310     C->record_failure("Must have MCs");
2311     return;
2312   }
2313   assert(!is_osr_parse(), "Not doing this for OSRs");
2314 
2315   // Set starting bci for uncommon trap.
2316   set_parse_bci(0);
2317 
2318   const TypePtr* adr_type = TypeRawPtr::make((address)mc);
2319   Node* mc_adr = makecon(adr_type);
2320   Node* cnt_adr = basic_plus_adr(mc_adr, mc_adr, in_bytes(MethodCounters::nmethod_age_offset()));
2321   Node* cnt = make_load(control(), cnt_adr, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
2322   Node* decr = _gvn.transform(new SubINode(cnt, makecon(TypeInt::ONE)));
2323   store_to_memory(control(), cnt_adr, decr, T_INT, adr_type, MemNode::unordered);
2324   Node *chk   = _gvn.transform(new CmpINode(decr, makecon(TypeInt::ZERO)));
2325   Node* tst   = _gvn.transform(new BoolNode(chk, BoolTest::gt));
2326   { BuildCutout unless(this, tst, PROB_ALWAYS);
2327     uncommon_trap(Deoptimization::Reason_tenured,
2328                   Deoptimization::Action_make_not_entrant);
2329   }
2330 }
2331 
2332 //------------------------------return_current---------------------------------
2333 // Append current _map to _exit_return
2334 void Parse::return_current(Node* value) {
2335   if (value != NULL && value->is_ValueType() && !_caller->has_method()) {
2336     // Returning a value type from root JVMState
2337     if (tf()->returns_value_type_as_fields()) {
2338       // Value type is returned as fields, make sure non-flattened value type fields are allocated
2339       value = value->as_ValueType()->allocate_fields(this);
2340     } else {
2341       // Value type is returned as oop, make sure it's allocated
2342       value = value->as_ValueType()->allocate(this)->get_oop();
2343     }
2344   }
2345 
2346   if (RegisterFinalizersAtInit &&
2347       method()->intrinsic_id() == vmIntrinsics::_Object_init) {
2348     call_register_finalizer();
2349   }
2350 
2351   // Do not set_parse_bci, so that return goo is credited to the return insn.
2352   // vreturn can trigger an allocation so vreturn can throw. Setting
2353   // the bci here breaks exception handling. Commenting this out
2354   // doesn't seem to break anything.
2355   //  set_bci(InvocationEntryBci);
2356   if (method()->is_synchronized() && GenerateSynchronizationCode) {
2357     shared_unlock(_synch_lock->box_node(), _synch_lock->obj_node());
2358   }
2359   if (C->env()->dtrace_method_probes()) {
2360     make_dtrace_method_exit(method());
2361   }
2362   // frame pointer is always same, already captured
2363   if (value != NULL) {
2364     Node* phi = _exits.argument(0);
2365     const TypeOopPtr* tr = phi->bottom_type()->isa_oopptr();
2366     if (tr && tr->isa_instptr() && tr->klass()->is_loaded() &&
2367         tr->klass()->is_interface()) {
2368       // If returning oops to an interface-return, there is a silent free
2369       // cast from oop to interface allowed by the Verifier. Make it explicit here.
2370       const TypeInstPtr* tp = value->bottom_type()->isa_instptr();
2371       if (tp && tp->klass()->is_loaded() && !tp->klass()->is_interface()) {
2372         // sharpen the type eagerly; this eases certain assert checking
2373         if (tp->higher_equal(TypeInstPtr::NOTNULL)) {
2374           tr = tr->join_speculative(TypeInstPtr::NOTNULL)->is_instptr();
2375         }
2376         value = _gvn.transform(new CheckCastPPNode(0, value, tr));
2377       }
2378     } else if (tr && tr->isa_instptr() && value->is_ValueType()) {
2379       // Value type to Object return
2380       assert(tr->isa_instptr()->klass()->is_java_lang_Object(), "must be java.lang.Object");
2381       assert(_caller->has_method(), "value type should be returned as oop");
2382     } else if (phi->bottom_type()->isa_valuetype() && !value->is_ValueType()) {
2383       assert(value->bottom_type()->remove_speculative() == TypePtr::NULL_PTR, "Anything other than null?");
2384       inc_sp(1);
2385       uncommon_trap(Deoptimization::Reason_null_check, Deoptimization::Action_none);
2386       dec_sp(1);
2387       return;
2388     } else {
2389       // Handle returns of oop-arrays to an arrays-of-interface return
2390       const TypeInstPtr* phi_tip;
2391       const TypeInstPtr* val_tip;
2392       Type::get_arrays_base_elements(phi->bottom_type(), value->bottom_type(), &phi_tip, &val_tip);
2393       if (phi_tip != NULL && phi_tip->is_loaded() && phi_tip->klass()->is_interface() &&
2394           val_tip != NULL && val_tip->is_loaded() && !val_tip->klass()->is_interface()) {
2395         value = _gvn.transform(new CheckCastPPNode(0, value, phi->bottom_type()));
2396       }
2397     }
2398     phi->add_req(value);
2399   }
2400 
2401   SafePointNode* exit_return = _exits.map();
2402   exit_return->in( TypeFunc::Control  )->add_req( control() );
2403   exit_return->in( TypeFunc::I_O      )->add_req( i_o    () );
2404   Node *mem = exit_return->in( TypeFunc::Memory   );
2405   for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
2406     if (mms.is_empty()) {
2407       // get a copy of the base memory, and patch just this one input
2408       const TypePtr* adr_type = mms.adr_type(C);
2409       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
2410       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
2411       gvn().set_type_bottom(phi);
2412       phi->del_req(phi->req()-1);  // prepare to re-patch
2413       mms.set_memory(phi);
2414     }
2415     mms.memory()->add_req(mms.memory2());
2416   }
2417 
2418   if (_first_return) {
2419     _exits.map()->transfer_replaced_nodes_from(map(), _new_idx);
2420     _first_return = false;
2421   } else {
2422     _exits.map()->merge_replaced_nodes_with(map());
2423   }
2424 
2425   stop_and_kill_map();          // This CFG path dies here
2426 }
2427 
2428 
2429 //------------------------------add_safepoint----------------------------------
2430 void Parse::add_safepoint() {
2431   // See if we can avoid this safepoint.  No need for a SafePoint immediately
2432   // after a Call (except Leaf Call) or another SafePoint.
2433   Node *proj = control();
2434   bool add_poll_param = SafePointNode::needs_polling_address_input();
2435   uint parms = add_poll_param ? TypeFunc::Parms+1 : TypeFunc::Parms;
2436   if( proj->is_Proj() ) {
2437     Node *n0 = proj->in(0);
2438     if( n0->is_Catch() ) {
2439       n0 = n0->in(0)->in(0);
2440       assert( n0->is_Call(), "expect a call here" );
2441     }
2442     if( n0->is_Call() ) {
2443       if( n0->as_Call()->guaranteed_safepoint() )
2444         return;
2445     } else if( n0->is_SafePoint() && n0->req() >= parms ) {
2446       return;
2447     }
2448   }
2449 
2450   // Clear out dead values from the debug info.
2451   kill_dead_locals();
2452 
2453   // Clone the JVM State
2454   SafePointNode *sfpnt = new SafePointNode(parms, NULL);
2455 
2456   // Capture memory state BEFORE a SafePoint.  Since we can block at a
2457   // SafePoint we need our GC state to be safe; i.e. we need all our current
2458   // write barriers (card marks) to not float down after the SafePoint so we
2459   // must read raw memory.  Likewise we need all oop stores to match the card
2460   // marks.  If deopt can happen, we need ALL stores (we need the correct JVM
2461   // state on a deopt).
2462 
2463   // We do not need to WRITE the memory state after a SafePoint.  The control
2464   // edge will keep card-marks and oop-stores from floating up from below a
2465   // SafePoint and our true dependency added here will keep them from floating
2466   // down below a SafePoint.
2467 
2468   // Clone the current memory state
2469   Node* mem = MergeMemNode::make(map()->memory());
2470 
2471   mem = _gvn.transform(mem);
2472 
2473   // Pass control through the safepoint
2474   sfpnt->init_req(TypeFunc::Control  , control());
2475   // Fix edges normally used by a call
2476   sfpnt->init_req(TypeFunc::I_O      , top() );
2477   sfpnt->init_req(TypeFunc::Memory   , mem   );
2478   sfpnt->init_req(TypeFunc::ReturnAdr, top() );
2479   sfpnt->init_req(TypeFunc::FramePtr , top() );
2480 
2481   // Create a node for the polling address
2482   if( add_poll_param ) {
2483     Node *polladr;
2484     if (SafepointMechanism::uses_thread_local_poll()) {
2485       Node *thread = _gvn.transform(new ThreadLocalNode());
2486       Node *polling_page_load_addr = _gvn.transform(basic_plus_adr(top(), thread, in_bytes(Thread::polling_page_offset())));
2487       polladr = make_load(control(), polling_page_load_addr, TypeRawPtr::BOTTOM, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
2488     } else {
2489       polladr = ConPNode::make((address)os::get_polling_page());
2490     }
2491     sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
2492   }
2493 
2494   // Fix up the JVM State edges
2495   add_safepoint_edges(sfpnt);
2496   Node *transformed_sfpnt = _gvn.transform(sfpnt);
2497   set_control(transformed_sfpnt);
2498 
2499   // Provide an edge from root to safepoint.  This makes the safepoint
2500   // appear useful until the parse has completed.
2501   if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
2502     assert(C->root() != NULL, "Expect parse is still valid");
2503     C->root()->add_prec(transformed_sfpnt);
2504   }
2505 }
2506 
2507 #ifndef PRODUCT
2508 //------------------------show_parse_info--------------------------------------
2509 void Parse::show_parse_info() {
2510   InlineTree* ilt = NULL;
2511   if (C->ilt() != NULL) {
2512     JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
2513     ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
2514   }
2515   if (PrintCompilation && Verbose) {
2516     if (depth() == 1) {
2517       if( ilt->count_inlines() ) {
2518         tty->print("    __inlined %d (%d bytes)", ilt->count_inlines(),
2519                      ilt->count_inline_bcs());
2520         tty->cr();
2521       }
2522     } else {
2523       if (method()->is_synchronized())         tty->print("s");
2524       if (method()->has_exception_handlers())  tty->print("!");
2525       // Check this is not the final compiled version
2526       if (C->trap_can_recompile()) {
2527         tty->print("-");
2528       } else {
2529         tty->print(" ");
2530       }
2531       method()->print_short_name();
2532       if (is_osr_parse()) {
2533         tty->print(" @ %d", osr_bci());
2534       }
2535       tty->print(" (%d bytes)",method()->code_size());
2536       if (ilt->count_inlines()) {
2537         tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2538                    ilt->count_inline_bcs());
2539       }
2540       tty->cr();
2541     }
2542   }
2543   if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
2544     // Print that we succeeded; suppress this message on the first osr parse.
2545 
2546     if (method()->is_synchronized())         tty->print("s");
2547     if (method()->has_exception_handlers())  tty->print("!");
2548     // Check this is not the final compiled version
2549     if (C->trap_can_recompile() && depth() == 1) {
2550       tty->print("-");
2551     } else {
2552       tty->print(" ");
2553     }
2554     if( depth() != 1 ) { tty->print("   "); }  // missing compile count
2555     for (int i = 1; i < depth(); ++i) { tty->print("  "); }
2556     method()->print_short_name();
2557     if (is_osr_parse()) {
2558       tty->print(" @ %d", osr_bci());
2559     }
2560     if (ilt->caller_bci() != -1) {
2561       tty->print(" @ %d", ilt->caller_bci());
2562     }
2563     tty->print(" (%d bytes)",method()->code_size());
2564     if (ilt->count_inlines()) {
2565       tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2566                  ilt->count_inline_bcs());
2567     }
2568     tty->cr();
2569   }
2570 }
2571 
2572 
2573 //------------------------------dump-------------------------------------------
2574 // Dump information associated with the bytecodes of current _method
2575 void Parse::dump() {
2576   if( method() != NULL ) {
2577     // Iterate over bytecodes
2578     ciBytecodeStream iter(method());
2579     for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
2580       dump_bci( iter.cur_bci() );
2581       tty->cr();
2582     }
2583   }
2584 }
2585 
2586 // Dump information associated with a byte code index, 'bci'
2587 void Parse::dump_bci(int bci) {
2588   // Output info on merge-points, cloning, and within _jsr..._ret
2589   // NYI
2590   tty->print(" bci:%d", bci);
2591 }
2592 
2593 #endif