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


2341         value = value->as_ValueType()->allocate_fields(this);
2342       } else {
2343         // Make sure value type is allocated
2344         value = value->as_ValueType()->allocate(this)->get_oop();
2345       }




2346     } else if (tr && tr->isa_instptr() && tr->klass()->is_loaded() && tr->klass()->is_interface()) {
2347       // If returning oops to an interface-return, there is a silent free
2348       // cast from oop to interface allowed by the Verifier. Make it explicit here.
2349       const TypeInstPtr* tp = value->bottom_type()->isa_instptr();
2350       if (tp && tp->klass()->is_loaded() && !tp->klass()->is_interface()) {
2351         // sharpen the type eagerly; this eases certain assert checking
2352         if (tp->higher_equal(TypeInstPtr::NOTNULL)) {
2353           tr = tr->join_speculative(TypeInstPtr::NOTNULL)->is_instptr();
2354         }
2355         value = _gvn.transform(new CheckCastPPNode(0, value, tr));
2356       }
2357     } else {
2358       // Handle returns of oop-arrays to an arrays-of-interface return
2359       const TypeInstPtr* phi_tip;
2360       const TypeInstPtr* val_tip;
2361       Type::get_arrays_base_elements(phi->bottom_type(), value->bottom_type(), &phi_tip, &val_tip);
2362       if (phi_tip != NULL && phi_tip->is_loaded() && phi_tip->klass()->is_interface() &&
2363           val_tip != NULL && val_tip->is_loaded() && !val_tip->klass()->is_interface()) {
2364         value = _gvn.transform(new CheckCastPPNode(0, value, phi->bottom_type()));
2365       }
2366     }
2367     phi->add_req(value);
2368   }
2369 
2370   SafePointNode* exit_return = _exits.map();
2371   exit_return->in( TypeFunc::Control  )->add_req( control() );
2372   exit_return->in( TypeFunc::I_O      )->add_req( i_o    () );
2373   Node *mem = exit_return->in( TypeFunc::Memory   );
2374   for (MergeMemStream mms(mem->as_MergeMem(), merged_memory()); mms.next_non_empty2(); ) {
2375     if (mms.is_empty()) {
2376       // get a copy of the base memory, and patch just this one input
2377       const TypePtr* adr_type = mms.adr_type(C);
2378       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
2379       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
2380       gvn().set_type_bottom(phi);
2381       phi->del_req(phi->req()-1);  // prepare to re-patch
2382       mms.set_memory(phi);
2383     }
2384     mms.memory()->add_req(mms.memory2());
2385   }
2386 
2387   if (_first_return) {
2388     _exits.map()->transfer_replaced_nodes_from(map(), _new_idx);
2389     _first_return = false;
2390   } else {
2391     _exits.map()->merge_replaced_nodes_with(map());
2392   }
2393 
2394   stop_and_kill_map();          // This CFG path dies here
2395 }
2396 
2397 
2398 //------------------------------add_safepoint----------------------------------
2399 void Parse::add_safepoint() {
2400   // See if we can avoid this safepoint.  No need for a SafePoint immediately
2401   // after a Call (except Leaf Call) or another SafePoint.
2402   Node *proj = control();
2403   bool add_poll_param = SafePointNode::needs_polling_address_input();
2404   uint parms = add_poll_param ? TypeFunc::Parms+1 : TypeFunc::Parms;
2405   if( proj->is_Proj() ) {
2406     Node *n0 = proj->in(0);
2407     if( n0->is_Catch() ) {
2408       n0 = n0->in(0)->in(0);
2409       assert( n0->is_Call(), "expect a call here" );
2410     }
2411     if( n0->is_Call() ) {
2412       if( n0->as_Call()->guaranteed_safepoint() )
2413         return;
2414     } else if( n0->is_SafePoint() && n0->req() >= parms ) {
2415       return;
2416     }
2417   }
2418 
2419   // Clear out dead values from the debug info.
2420   kill_dead_locals();
2421 
2422   // Clone the JVM State
2423   SafePointNode *sfpnt = new SafePointNode(parms, NULL);
2424 
2425   // Capture memory state BEFORE a SafePoint.  Since we can block at a
2426   // SafePoint we need our GC state to be safe; i.e. we need all our current
2427   // write barriers (card marks) to not float down after the SafePoint so we
2428   // must read raw memory.  Likewise we need all oop stores to match the card
2429   // marks.  If deopt can happen, we need ALL stores (we need the correct JVM
2430   // state on a deopt).
2431 
2432   // We do not need to WRITE the memory state after a SafePoint.  The control
2433   // edge will keep card-marks and oop-stores from floating up from below a
2434   // SafePoint and our true dependency added here will keep them from floating
2435   // down below a SafePoint.
2436 
2437   // Clone the current memory state
2438   Node* mem = MergeMemNode::make(map()->memory());
2439 
2440   mem = _gvn.transform(mem);
2441 
2442   // Pass control through the safepoint
2443   sfpnt->init_req(TypeFunc::Control  , control());
2444   // Fix edges normally used by a call
2445   sfpnt->init_req(TypeFunc::I_O      , top() );
2446   sfpnt->init_req(TypeFunc::Memory   , mem   );
2447   sfpnt->init_req(TypeFunc::ReturnAdr, top() );
2448   sfpnt->init_req(TypeFunc::FramePtr , top() );
2449 
2450   // Create a node for the polling address
2451   if( add_poll_param ) {
2452     Node *polladr;
2453     if (SafepointMechanism::uses_thread_local_poll()) {
2454       Node *thread = _gvn.transform(new ThreadLocalNode());
2455       Node *polling_page_load_addr = _gvn.transform(basic_plus_adr(top(), thread, in_bytes(Thread::polling_page_offset())));
2456       polladr = make_load(control(), polling_page_load_addr, TypeRawPtr::BOTTOM, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
2457     } else {
2458       polladr = ConPNode::make((address)os::get_polling_page());
2459     }
2460     sfpnt->init_req(TypeFunc::Parms+0, _gvn.transform(polladr));
2461   }
2462 
2463   // Fix up the JVM State edges
2464   add_safepoint_edges(sfpnt);
2465   Node *transformed_sfpnt = _gvn.transform(sfpnt);
2466   set_control(transformed_sfpnt);
2467 
2468   // Provide an edge from root to safepoint.  This makes the safepoint
2469   // appear useful until the parse has completed.
2470   if( OptoRemoveUseless && transformed_sfpnt->is_SafePoint() ) {
2471     assert(C->root() != NULL, "Expect parse is still valid");
2472     C->root()->add_prec(transformed_sfpnt);
2473   }
2474 }
2475 
2476 #ifndef PRODUCT
2477 //------------------------show_parse_info--------------------------------------
2478 void Parse::show_parse_info() {
2479   InlineTree* ilt = NULL;
2480   if (C->ilt() != NULL) {
2481     JVMState* caller_jvms = is_osr_parse() ? caller()->caller() : caller();
2482     ilt = InlineTree::find_subtree_from_root(C->ilt(), caller_jvms, method());
2483   }
2484   if (PrintCompilation && Verbose) {
2485     if (depth() == 1) {
2486       if( ilt->count_inlines() ) {
2487         tty->print("    __inlined %d (%d bytes)", ilt->count_inlines(),
2488                      ilt->count_inline_bcs());
2489         tty->cr();
2490       }
2491     } else {
2492       if (method()->is_synchronized())         tty->print("s");
2493       if (method()->has_exception_handlers())  tty->print("!");
2494       // Check this is not the final compiled version
2495       if (C->trap_can_recompile()) {
2496         tty->print("-");
2497       } else {
2498         tty->print(" ");
2499       }
2500       method()->print_short_name();
2501       if (is_osr_parse()) {
2502         tty->print(" @ %d", osr_bci());
2503       }
2504       tty->print(" (%d bytes)",method()->code_size());
2505       if (ilt->count_inlines()) {
2506         tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2507                    ilt->count_inline_bcs());
2508       }
2509       tty->cr();
2510     }
2511   }
2512   if (PrintOpto && (depth() == 1 || PrintOptoInlining)) {
2513     // Print that we succeeded; suppress this message on the first osr parse.
2514 
2515     if (method()->is_synchronized())         tty->print("s");
2516     if (method()->has_exception_handlers())  tty->print("!");
2517     // Check this is not the final compiled version
2518     if (C->trap_can_recompile() && depth() == 1) {
2519       tty->print("-");
2520     } else {
2521       tty->print(" ");
2522     }
2523     if( depth() != 1 ) { tty->print("   "); }  // missing compile count
2524     for (int i = 1; i < depth(); ++i) { tty->print("  "); }
2525     method()->print_short_name();
2526     if (is_osr_parse()) {
2527       tty->print(" @ %d", osr_bci());
2528     }
2529     if (ilt->caller_bci() != -1) {
2530       tty->print(" @ %d", ilt->caller_bci());
2531     }
2532     tty->print(" (%d bytes)",method()->code_size());
2533     if (ilt->count_inlines()) {
2534       tty->print(" __inlined %d (%d bytes)", ilt->count_inlines(),
2535                  ilt->count_inline_bcs());
2536     }
2537     tty->cr();
2538   }
2539 }
2540 
2541 
2542 //------------------------------dump-------------------------------------------
2543 // Dump information associated with the bytecodes of current _method
2544 void Parse::dump() {
2545   if( method() != NULL ) {
2546     // Iterate over bytecodes
2547     ciBytecodeStream iter(method());
2548     for( Bytecodes::Code bc = iter.next(); bc != ciBytecodeStream::EOBC() ; bc = iter.next() ) {
2549       dump_bci( iter.cur_bci() );
2550       tty->cr();
2551     }
2552   }
2553 }
2554 
2555 // Dump information associated with a byte code index, 'bci'
2556 void Parse::dump_bci(int bci) {
2557   // Output info on merge-points, cloning, and within _jsr..._ret
2558   // NYI
2559   tty->print(" bci:%d", bci);
2560 }
2561 
2562 #endif
--- EOF ---