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 "ci/bcEscapeAnalyzer.hpp"
  28 #include "compiler/oopMap.hpp"
  29 #include "gc/shared/barrierSet.hpp"
  30 #include "gc/shared/c2/barrierSetC2.hpp"
  31 #include "interpreter/interpreter.hpp"
  32 #include "opto/callGenerator.hpp"
  33 #include "opto/callnode.hpp"
  34 #include "opto/castnode.hpp"
  35 #include "opto/convertnode.hpp"
  36 #include "opto/escape.hpp"
  37 #include "opto/locknode.hpp"
  38 #include "opto/machnode.hpp"
  39 #include "opto/matcher.hpp"
  40 #include "opto/parse.hpp"
  41 #include "opto/regalloc.hpp"
  42 #include "opto/regmask.hpp"
  43 #include "opto/rootnode.hpp"
  44 #include "opto/runtime.hpp"
  45 
  46 // Portions of code courtesy of Clifford Click
  47 
  48 // Optimization - Graph Style
  49 
  50 //=============================================================================
  51 uint StartNode::size_of() const { return sizeof(*this); }
  52 uint StartNode::cmp( const Node &n ) const
  53 { return _domain == ((StartNode&)n)._domain; }
  54 const Type *StartNode::bottom_type() const { return _domain; }
  55 const Type* StartNode::Value(PhaseGVN* phase) const { return _domain; }
  56 #ifndef PRODUCT
  57 void StartNode::dump_spec(outputStream *st) const { st->print(" #"); _domain->dump_on(st);}
  58 void StartNode::dump_compact_spec(outputStream *st) const { /* empty */ }
  59 #endif
  60 
  61 //------------------------------Ideal------------------------------------------
  62 Node *StartNode::Ideal(PhaseGVN *phase, bool can_reshape){
  63   return remove_dead_region(phase, can_reshape) ? this : NULL;
  64 }
  65 
  66 //------------------------------calling_convention-----------------------------
  67 void StartNode::calling_convention( BasicType* sig_bt, VMRegPair *parm_regs, uint argcnt ) const {
  68   Matcher::calling_convention( sig_bt, parm_regs, argcnt, false );
  69 }
  70 
  71 //------------------------------Registers--------------------------------------
  72 const RegMask &StartNode::in_RegMask(uint) const {
  73   return RegMask::Empty;
  74 }
  75 
  76 //------------------------------match------------------------------------------
  77 // Construct projections for incoming parameters, and their RegMask info
  78 Node *StartNode::match( const ProjNode *proj, const Matcher *match ) {
  79   switch (proj->_con) {
  80   case TypeFunc::Control:
  81   case TypeFunc::I_O:
  82   case TypeFunc::Memory:
  83     return new MachProjNode(this,proj->_con,RegMask::Empty,MachProjNode::unmatched_proj);
  84   case TypeFunc::FramePtr:
  85     return new MachProjNode(this,proj->_con,Matcher::c_frame_ptr_mask, Op_RegP);
  86   case TypeFunc::ReturnAdr:
  87     return new MachProjNode(this,proj->_con,match->_return_addr_mask,Op_RegP);
  88   case TypeFunc::Parms:
  89   default: {
  90       uint parm_num = proj->_con - TypeFunc::Parms;
  91       const Type *t = _domain->field_at(proj->_con);
  92       if (t->base() == Type::Half)  // 2nd half of Longs and Doubles
  93         return new ConNode(Type::TOP);
  94       uint ideal_reg = t->ideal_reg();
  95       RegMask &rm = match->_calling_convention_mask[parm_num];
  96       return new MachProjNode(this,proj->_con,rm,ideal_reg);
  97     }
  98   }
  99   return NULL;
 100 }
 101 
 102 //------------------------------StartOSRNode----------------------------------
 103 // The method start node for an on stack replacement adapter
 104 
 105 //------------------------------osr_domain-----------------------------
 106 const TypeTuple *StartOSRNode::osr_domain() {
 107   const Type **fields = TypeTuple::fields(2);
 108   fields[TypeFunc::Parms+0] = TypeRawPtr::BOTTOM;  // address of osr buffer
 109 
 110   return TypeTuple::make(TypeFunc::Parms+1, fields);
 111 }
 112 
 113 //=============================================================================
 114 const char * const ParmNode::names[TypeFunc::Parms+1] = {
 115   "Control", "I_O", "Memory", "FramePtr", "ReturnAdr", "Parms"
 116 };
 117 
 118 #ifndef PRODUCT
 119 void ParmNode::dump_spec(outputStream *st) const {
 120   if( _con < TypeFunc::Parms ) {
 121     st->print("%s", names[_con]);
 122   } else {
 123     st->print("Parm%d: ",_con-TypeFunc::Parms);
 124     // Verbose and WizardMode dump bottom_type for all nodes
 125     if( !Verbose && !WizardMode )   bottom_type()->dump_on(st);
 126   }
 127 }
 128 
 129 void ParmNode::dump_compact_spec(outputStream *st) const {
 130   if (_con < TypeFunc::Parms) {
 131     st->print("%s", names[_con]);
 132   } else {
 133     st->print("%d:", _con-TypeFunc::Parms);
 134     // unconditionally dump bottom_type
 135     bottom_type()->dump_on(st);
 136   }
 137 }
 138 
 139 // For a ParmNode, all immediate inputs and outputs are considered relevant
 140 // both in compact and standard representation.
 141 void ParmNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
 142   this->collect_nodes(in_rel, 1, false, false);
 143   this->collect_nodes(out_rel, -1, false, false);
 144 }
 145 #endif
 146 
 147 uint ParmNode::ideal_reg() const {
 148   switch( _con ) {
 149   case TypeFunc::Control  : // fall through
 150   case TypeFunc::I_O      : // fall through
 151   case TypeFunc::Memory   : return 0;
 152   case TypeFunc::FramePtr : // fall through
 153   case TypeFunc::ReturnAdr: return Op_RegP;
 154   default                 : assert( _con > TypeFunc::Parms, "" );
 155     // fall through
 156   case TypeFunc::Parms    : {
 157     // Type of argument being passed
 158     const Type *t = in(0)->as_Start()->_domain->field_at(_con);
 159     return t->ideal_reg();
 160   }
 161   }
 162   ShouldNotReachHere();
 163   return 0;
 164 }
 165 
 166 //=============================================================================
 167 ReturnNode::ReturnNode(uint edges, Node *cntrl, Node *i_o, Node *memory, Node *frameptr, Node *retadr ) : Node(edges) {
 168   init_req(TypeFunc::Control,cntrl);
 169   init_req(TypeFunc::I_O,i_o);
 170   init_req(TypeFunc::Memory,memory);
 171   init_req(TypeFunc::FramePtr,frameptr);
 172   init_req(TypeFunc::ReturnAdr,retadr);
 173 }
 174 
 175 Node *ReturnNode::Ideal(PhaseGVN *phase, bool can_reshape){
 176   return remove_dead_region(phase, can_reshape) ? this : NULL;
 177 }
 178 
 179 const Type* ReturnNode::Value(PhaseGVN* phase) const {
 180   return ( phase->type(in(TypeFunc::Control)) == Type::TOP)
 181     ? Type::TOP
 182     : Type::BOTTOM;
 183 }
 184 
 185 // Do we Match on this edge index or not?  No edges on return nodes
 186 uint ReturnNode::match_edge(uint idx) const {
 187   return 0;
 188 }
 189 
 190 
 191 #ifndef PRODUCT
 192 void ReturnNode::dump_req(outputStream *st) const {
 193   // Dump the required inputs, enclosed in '(' and ')'
 194   uint i;                       // Exit value of loop
 195   for (i = 0; i < req(); i++) {    // For all required inputs
 196     if (i == TypeFunc::Parms) st->print("returns");
 197     if (in(i)) st->print("%c%d ", Compile::current()->node_arena()->contains(in(i)) ? ' ' : 'o', in(i)->_idx);
 198     else st->print("_ ");
 199   }
 200 }
 201 #endif
 202 
 203 //=============================================================================
 204 RethrowNode::RethrowNode(
 205   Node* cntrl,
 206   Node* i_o,
 207   Node* memory,
 208   Node* frameptr,
 209   Node* ret_adr,
 210   Node* exception
 211 ) : Node(TypeFunc::Parms + 1) {
 212   init_req(TypeFunc::Control  , cntrl    );
 213   init_req(TypeFunc::I_O      , i_o      );
 214   init_req(TypeFunc::Memory   , memory   );
 215   init_req(TypeFunc::FramePtr , frameptr );
 216   init_req(TypeFunc::ReturnAdr, ret_adr);
 217   init_req(TypeFunc::Parms    , exception);
 218 }
 219 
 220 Node *RethrowNode::Ideal(PhaseGVN *phase, bool can_reshape){
 221   return remove_dead_region(phase, can_reshape) ? this : NULL;
 222 }
 223 
 224 const Type* RethrowNode::Value(PhaseGVN* phase) const {
 225   return (phase->type(in(TypeFunc::Control)) == Type::TOP)
 226     ? Type::TOP
 227     : Type::BOTTOM;
 228 }
 229 
 230 uint RethrowNode::match_edge(uint idx) const {
 231   return 0;
 232 }
 233 
 234 #ifndef PRODUCT
 235 void RethrowNode::dump_req(outputStream *st) const {
 236   // Dump the required inputs, enclosed in '(' and ')'
 237   uint i;                       // Exit value of loop
 238   for (i = 0; i < req(); i++) {    // For all required inputs
 239     if (i == TypeFunc::Parms) st->print("exception");
 240     if (in(i)) st->print("%c%d ", Compile::current()->node_arena()->contains(in(i)) ? ' ' : 'o', in(i)->_idx);
 241     else st->print("_ ");
 242   }
 243 }
 244 #endif
 245 
 246 //=============================================================================
 247 // Do we Match on this edge index or not?  Match only target address & method
 248 uint TailCallNode::match_edge(uint idx) const {
 249   return TypeFunc::Parms <= idx  &&  idx <= TypeFunc::Parms+1;
 250 }
 251 
 252 //=============================================================================
 253 // Do we Match on this edge index or not?  Match only target address & oop
 254 uint TailJumpNode::match_edge(uint idx) const {
 255   return TypeFunc::Parms <= idx  &&  idx <= TypeFunc::Parms+1;
 256 }
 257 
 258 //=============================================================================
 259 JVMState::JVMState(ciMethod* method, JVMState* caller) :
 260   _method(method) {
 261   assert(method != NULL, "must be valid call site");
 262   _bci = InvocationEntryBci;
 263   _reexecute = Reexecute_Undefined;
 264   debug_only(_bci = -99);  // random garbage value
 265   debug_only(_map = (SafePointNode*)-1);
 266   _caller = caller;
 267   _depth  = 1 + (caller == NULL ? 0 : caller->depth());
 268   _locoff = TypeFunc::Parms;
 269   _stkoff = _locoff + _method->max_locals();
 270   _monoff = _stkoff + _method->max_stack();
 271   _scloff = _monoff;
 272   _endoff = _monoff;
 273   _sp = 0;
 274 }
 275 JVMState::JVMState(int stack_size) :
 276   _method(NULL) {
 277   _bci = InvocationEntryBci;
 278   _reexecute = Reexecute_Undefined;
 279   debug_only(_map = (SafePointNode*)-1);
 280   _caller = NULL;
 281   _depth  = 1;
 282   _locoff = TypeFunc::Parms;
 283   _stkoff = _locoff;
 284   _monoff = _stkoff + stack_size;
 285   _scloff = _monoff;
 286   _endoff = _monoff;
 287   _sp = 0;
 288 }
 289 
 290 //--------------------------------of_depth-------------------------------------
 291 JVMState* JVMState::of_depth(int d) const {
 292   const JVMState* jvmp = this;
 293   assert(0 < d && (uint)d <= depth(), "oob");
 294   for (int skip = depth() - d; skip > 0; skip--) {
 295     jvmp = jvmp->caller();
 296   }
 297   assert(jvmp->depth() == (uint)d, "found the right one");
 298   return (JVMState*)jvmp;
 299 }
 300 
 301 //-----------------------------same_calls_as-----------------------------------
 302 bool JVMState::same_calls_as(const JVMState* that) const {
 303   if (this == that)                    return true;
 304   if (this->depth() != that->depth())  return false;
 305   const JVMState* p = this;
 306   const JVMState* q = that;
 307   for (;;) {
 308     if (p->_method != q->_method)    return false;
 309     if (p->_method == NULL)          return true;   // bci is irrelevant
 310     if (p->_bci    != q->_bci)       return false;
 311     if (p->_reexecute != q->_reexecute)  return false;
 312     p = p->caller();
 313     q = q->caller();
 314     if (p == q)                      return true;
 315     assert(p != NULL && q != NULL, "depth check ensures we don't run off end");
 316   }
 317 }
 318 
 319 //------------------------------debug_start------------------------------------
 320 uint JVMState::debug_start()  const {
 321   debug_only(JVMState* jvmroot = of_depth(1));
 322   assert(jvmroot->locoff() <= this->locoff(), "youngest JVMState must be last");
 323   return of_depth(1)->locoff();
 324 }
 325 
 326 //-------------------------------debug_end-------------------------------------
 327 uint JVMState::debug_end() const {
 328   debug_only(JVMState* jvmroot = of_depth(1));
 329   assert(jvmroot->endoff() <= this->endoff(), "youngest JVMState must be last");
 330   return endoff();
 331 }
 332 
 333 //------------------------------debug_depth------------------------------------
 334 uint JVMState::debug_depth() const {
 335   uint total = 0;
 336   for (const JVMState* jvmp = this; jvmp != NULL; jvmp = jvmp->caller()) {
 337     total += jvmp->debug_size();
 338   }
 339   return total;
 340 }
 341 
 342 #ifndef PRODUCT
 343 
 344 //------------------------------format_helper----------------------------------
 345 // Given an allocation (a Chaitin object) and a Node decide if the Node carries
 346 // any defined value or not.  If it does, print out the register or constant.
 347 static void format_helper( PhaseRegAlloc *regalloc, outputStream* st, Node *n, const char *msg, uint i, GrowableArray<SafePointScalarObjectNode*> *scobjs ) {
 348   if (n == NULL) { st->print(" NULL"); return; }
 349   if (n->is_SafePointScalarObject()) {
 350     // Scalar replacement.
 351     SafePointScalarObjectNode* spobj = n->as_SafePointScalarObject();
 352     scobjs->append_if_missing(spobj);
 353     int sco_n = scobjs->find(spobj);
 354     assert(sco_n >= 0, "");
 355     st->print(" %s%d]=#ScObj" INT32_FORMAT, msg, i, sco_n);
 356     return;
 357   }
 358   if (regalloc->node_regs_max_index() > 0 &&
 359       OptoReg::is_valid(regalloc->get_reg_first(n))) { // Check for undefined
 360     char buf[50];
 361     regalloc->dump_register(n,buf);
 362     st->print(" %s%d]=%s",msg,i,buf);
 363   } else {                      // No register, but might be constant
 364     const Type *t = n->bottom_type();
 365     switch (t->base()) {
 366     case Type::Int:
 367       st->print(" %s%d]=#" INT32_FORMAT,msg,i,t->is_int()->get_con());
 368       break;
 369     case Type::AnyPtr:
 370       assert( t == TypePtr::NULL_PTR || n->in_dump(), "" );
 371       st->print(" %s%d]=#NULL",msg,i);
 372       break;
 373     case Type::AryPtr:
 374     case Type::InstPtr:
 375       st->print(" %s%d]=#Ptr" INTPTR_FORMAT,msg,i,p2i(t->isa_oopptr()->const_oop()));
 376       break;
 377     case Type::KlassPtr:
 378       st->print(" %s%d]=#Ptr" INTPTR_FORMAT,msg,i,p2i(t->make_ptr()->isa_klassptr()->klass()));
 379       break;
 380     case Type::MetadataPtr:
 381       st->print(" %s%d]=#Ptr" INTPTR_FORMAT,msg,i,p2i(t->make_ptr()->isa_metadataptr()->metadata()));
 382       break;
 383     case Type::NarrowOop:
 384       st->print(" %s%d]=#Ptr" INTPTR_FORMAT,msg,i,p2i(t->make_ptr()->isa_oopptr()->const_oop()));
 385       break;
 386     case Type::RawPtr:
 387       st->print(" %s%d]=#Raw" INTPTR_FORMAT,msg,i,p2i(t->is_rawptr()));
 388       break;
 389     case Type::DoubleCon:
 390       st->print(" %s%d]=#%fD",msg,i,t->is_double_constant()->_d);
 391       break;
 392     case Type::FloatCon:
 393       st->print(" %s%d]=#%fF",msg,i,t->is_float_constant()->_f);
 394       break;
 395     case Type::Long:
 396       st->print(" %s%d]=#" INT64_FORMAT,msg,i,(int64_t)(t->is_long()->get_con()));
 397       break;
 398     case Type::Half:
 399     case Type::Top:
 400       st->print(" %s%d]=_",msg,i);
 401       break;
 402     default: ShouldNotReachHere();
 403     }
 404   }
 405 }
 406 
 407 //------------------------------format-----------------------------------------
 408 void JVMState::format(PhaseRegAlloc *regalloc, const Node *n, outputStream* st) const {
 409   st->print("        #");
 410   if (_method) {
 411     _method->print_short_name(st);
 412     st->print(" @ bci:%d ",_bci);
 413   } else {
 414     st->print_cr(" runtime stub ");
 415     return;
 416   }
 417   if (n->is_MachSafePoint()) {
 418     GrowableArray<SafePointScalarObjectNode*> scobjs;
 419     MachSafePointNode *mcall = n->as_MachSafePoint();
 420     uint i;
 421     // Print locals
 422     for (i = 0; i < (uint)loc_size(); i++)
 423       format_helper(regalloc, st, mcall->local(this, i), "L[", i, &scobjs);
 424     // Print stack
 425     for (i = 0; i < (uint)stk_size(); i++) {
 426       if ((uint)(_stkoff + i) >= mcall->len())
 427         st->print(" oob ");
 428       else
 429        format_helper(regalloc, st, mcall->stack(this, i), "STK[", i, &scobjs);
 430     }
 431     for (i = 0; (int)i < nof_monitors(); i++) {
 432       Node *box = mcall->monitor_box(this, i);
 433       Node *obj = mcall->monitor_obj(this, i);
 434       if (regalloc->node_regs_max_index() > 0 &&
 435           OptoReg::is_valid(regalloc->get_reg_first(box))) {
 436         box = BoxLockNode::box_node(box);
 437         format_helper(regalloc, st, box, "MON-BOX[", i, &scobjs);
 438       } else {
 439         OptoReg::Name box_reg = BoxLockNode::reg(box);
 440         st->print(" MON-BOX%d=%s+%d",
 441                    i,
 442                    OptoReg::regname(OptoReg::c_frame_pointer),
 443                    regalloc->reg2offset(box_reg));
 444       }
 445       const char* obj_msg = "MON-OBJ[";
 446       if (EliminateLocks) {
 447         if (BoxLockNode::box_node(box)->is_eliminated())
 448           obj_msg = "MON-OBJ(LOCK ELIMINATED)[";
 449       }
 450       format_helper(regalloc, st, obj, obj_msg, i, &scobjs);
 451     }
 452 
 453     for (i = 0; i < (uint)scobjs.length(); i++) {
 454       // Scalar replaced objects.
 455       st->cr();
 456       st->print("        # ScObj" INT32_FORMAT " ", i);
 457       SafePointScalarObjectNode* spobj = scobjs.at(i);
 458       ciKlass* cik = spobj->bottom_type()->is_oopptr()->klass();
 459       assert(cik->is_instance_klass() ||
 460              cik->is_array_klass(), "Not supported allocation.");
 461       ciInstanceKlass *iklass = NULL;
 462       if (cik->is_instance_klass()) {
 463         cik->print_name_on(st);
 464         iklass = cik->as_instance_klass();
 465       } else if (cik->is_type_array_klass()) {
 466         cik->as_array_klass()->base_element_type()->print_name_on(st);
 467         st->print("[%d]", spobj->n_fields());
 468       } else if (cik->is_obj_array_klass()) {
 469         ciKlass* cie = cik->as_obj_array_klass()->base_element_klass();
 470         if (cie->is_instance_klass()) {
 471           cie->print_name_on(st);
 472         } else if (cie->is_type_array_klass()) {
 473           cie->as_array_klass()->base_element_type()->print_name_on(st);
 474         } else {
 475           ShouldNotReachHere();
 476         }
 477         st->print("[%d]", spobj->n_fields());
 478         int ndim = cik->as_array_klass()->dimension() - 1;
 479         while (ndim-- > 0) {
 480           st->print("[]");
 481         }
 482       }
 483       st->print("={");
 484       uint nf = spobj->n_fields();
 485       if (nf > 0) {
 486         uint first_ind = spobj->first_index(mcall->jvms());
 487         Node* fld_node = mcall->in(first_ind);
 488         ciField* cifield;
 489         if (iklass != NULL) {
 490           st->print(" [");
 491           cifield = iklass->nonstatic_field_at(0);
 492           cifield->print_name_on(st);
 493           format_helper(regalloc, st, fld_node, ":", 0, &scobjs);
 494         } else {
 495           format_helper(regalloc, st, fld_node, "[", 0, &scobjs);
 496         }
 497         for (uint j = 1; j < nf; j++) {
 498           fld_node = mcall->in(first_ind+j);
 499           if (iklass != NULL) {
 500             st->print(", [");
 501             cifield = iklass->nonstatic_field_at(j);
 502             cifield->print_name_on(st);
 503             format_helper(regalloc, st, fld_node, ":", j, &scobjs);
 504           } else {
 505             format_helper(regalloc, st, fld_node, ", [", j, &scobjs);
 506           }
 507         }
 508       }
 509       st->print(" }");
 510     }
 511   }
 512   st->cr();
 513   if (caller() != NULL) caller()->format(regalloc, n, st);
 514 }
 515 
 516 
 517 void JVMState::dump_spec(outputStream *st) const {
 518   if (_method != NULL) {
 519     bool printed = false;
 520     if (!Verbose) {
 521       // The JVMS dumps make really, really long lines.
 522       // Take out the most boring parts, which are the package prefixes.
 523       char buf[500];
 524       stringStream namest(buf, sizeof(buf));
 525       _method->print_short_name(&namest);
 526       if (namest.count() < sizeof(buf)) {
 527         const char* name = namest.base();
 528         if (name[0] == ' ')  ++name;
 529         const char* endcn = strchr(name, ':');  // end of class name
 530         if (endcn == NULL)  endcn = strchr(name, '(');
 531         if (endcn == NULL)  endcn = name + strlen(name);
 532         while (endcn > name && endcn[-1] != '.' && endcn[-1] != '/')
 533           --endcn;
 534         st->print(" %s", endcn);
 535         printed = true;
 536       }
 537     }
 538     if (!printed)
 539       _method->print_short_name(st);
 540     st->print(" @ bci:%d",_bci);
 541     if(_reexecute == Reexecute_True)
 542       st->print(" reexecute");
 543   } else {
 544     st->print(" runtime stub");
 545   }
 546   if (caller() != NULL)  caller()->dump_spec(st);
 547 }
 548 
 549 
 550 void JVMState::dump_on(outputStream* st) const {
 551   bool print_map = _map && !((uintptr_t)_map & 1) &&
 552                   ((caller() == NULL) || (caller()->map() != _map));
 553   if (print_map) {
 554     if (_map->len() > _map->req()) {  // _map->has_exceptions()
 555       Node* ex = _map->in(_map->req());  // _map->next_exception()
 556       // skip the first one; it's already being printed
 557       while (ex != NULL && ex->len() > ex->req()) {
 558         ex = ex->in(ex->req());  // ex->next_exception()
 559         ex->dump(1);
 560       }
 561     }
 562     _map->dump(Verbose ? 2 : 1);
 563   }
 564   if (caller() != NULL) {
 565     caller()->dump_on(st);
 566   }
 567   st->print("JVMS depth=%d loc=%d stk=%d arg=%d mon=%d scalar=%d end=%d mondepth=%d sp=%d bci=%d reexecute=%s method=",
 568              depth(), locoff(), stkoff(), argoff(), monoff(), scloff(), endoff(), monitor_depth(), sp(), bci(), should_reexecute()?"true":"false");
 569   if (_method == NULL) {
 570     st->print_cr("(none)");
 571   } else {
 572     _method->print_name(st);
 573     st->cr();
 574     if (bci() >= 0 && bci() < _method->code_size()) {
 575       st->print("    bc: ");
 576       _method->print_codes_on(bci(), bci()+1, st);
 577     }
 578   }
 579 }
 580 
 581 // Extra way to dump a jvms from the debugger,
 582 // to avoid a bug with C++ member function calls.
 583 void dump_jvms(JVMState* jvms) {
 584   jvms->dump();
 585 }
 586 #endif
 587 
 588 //--------------------------clone_shallow--------------------------------------
 589 JVMState* JVMState::clone_shallow(Compile* C) const {
 590   JVMState* n = has_method() ? new (C) JVMState(_method, _caller) : new (C) JVMState(0);
 591   n->set_bci(_bci);
 592   n->_reexecute = _reexecute;
 593   n->set_locoff(_locoff);
 594   n->set_stkoff(_stkoff);
 595   n->set_monoff(_monoff);
 596   n->set_scloff(_scloff);
 597   n->set_endoff(_endoff);
 598   n->set_sp(_sp);
 599   n->set_map(_map);
 600   return n;
 601 }
 602 
 603 //---------------------------clone_deep----------------------------------------
 604 JVMState* JVMState::clone_deep(Compile* C) const {
 605   JVMState* n = clone_shallow(C);
 606   for (JVMState* p = n; p->_caller != NULL; p = p->_caller) {
 607     p->_caller = p->_caller->clone_shallow(C);
 608   }
 609   assert(n->depth() == depth(), "sanity");
 610   assert(n->debug_depth() == debug_depth(), "sanity");
 611   return n;
 612 }
 613 
 614 /**
 615  * Reset map for all callers
 616  */
 617 void JVMState::set_map_deep(SafePointNode* map) {
 618   for (JVMState* p = this; p->_caller != NULL; p = p->_caller) {
 619     p->set_map(map);
 620   }
 621 }
 622 
 623 // Adapt offsets in in-array after adding or removing an edge.
 624 // Prerequisite is that the JVMState is used by only one node.
 625 void JVMState::adapt_position(int delta) {
 626   for (JVMState* jvms = this; jvms != NULL; jvms = jvms->caller()) {
 627     jvms->set_locoff(jvms->locoff() + delta);
 628     jvms->set_stkoff(jvms->stkoff() + delta);
 629     jvms->set_monoff(jvms->monoff() + delta);
 630     jvms->set_scloff(jvms->scloff() + delta);
 631     jvms->set_endoff(jvms->endoff() + delta);
 632   }
 633 }
 634 
 635 // Mirror the stack size calculation in the deopt code
 636 // How much stack space would we need at this point in the program in
 637 // case of deoptimization?
 638 int JVMState::interpreter_frame_size() const {
 639   const JVMState* jvms = this;
 640   int size = 0;
 641   int callee_parameters = 0;
 642   int callee_locals = 0;
 643   int extra_args = method()->max_stack() - stk_size();
 644 
 645   while (jvms != NULL) {
 646     int locks = jvms->nof_monitors();
 647     int temps = jvms->stk_size();
 648     bool is_top_frame = (jvms == this);
 649     ciMethod* method = jvms->method();
 650 
 651     int frame_size = BytesPerWord * Interpreter::size_activation(method->max_stack(),
 652                                                                  temps + callee_parameters,
 653                                                                  extra_args,
 654                                                                  locks,
 655                                                                  callee_parameters,
 656                                                                  callee_locals,
 657                                                                  is_top_frame);
 658     size += frame_size;
 659 
 660     callee_parameters = method->size_of_parameters();
 661     callee_locals = method->max_locals();
 662     extra_args = 0;
 663     jvms = jvms->caller();
 664   }
 665   return size + Deoptimization::last_frame_adjust(0, callee_locals) * BytesPerWord;
 666 }
 667 
 668 //=============================================================================
 669 uint CallNode::cmp( const Node &n ) const
 670 { return _tf == ((CallNode&)n)._tf && _jvms == ((CallNode&)n)._jvms; }
 671 #ifndef PRODUCT
 672 void CallNode::dump_req(outputStream *st) const {
 673   // Dump the required inputs, enclosed in '(' and ')'
 674   uint i;                       // Exit value of loop
 675   for (i = 0; i < req(); i++) {    // For all required inputs
 676     if (i == TypeFunc::Parms) st->print("(");
 677     if (in(i)) st->print("%c%d ", Compile::current()->node_arena()->contains(in(i)) ? ' ' : 'o', in(i)->_idx);
 678     else st->print("_ ");
 679   }
 680   st->print(")");
 681 }
 682 
 683 void CallNode::dump_spec(outputStream *st) const {
 684   st->print(" ");
 685   if (tf() != NULL)  tf()->dump_on(st);
 686   if (_cnt != COUNT_UNKNOWN)  st->print(" C=%f",_cnt);
 687   if (jvms() != NULL)  jvms()->dump_spec(st);
 688 }
 689 #endif
 690 
 691 const Type *CallNode::bottom_type() const { return tf()->range(); }
 692 const Type* CallNode::Value(PhaseGVN* phase) const {
 693   if (phase->type(in(0)) == Type::TOP)  return Type::TOP;
 694   return tf()->range();
 695 }
 696 
 697 //------------------------------calling_convention-----------------------------
 698 void CallNode::calling_convention( BasicType* sig_bt, VMRegPair *parm_regs, uint argcnt ) const {
 699   // Use the standard compiler calling convention
 700   Matcher::calling_convention( sig_bt, parm_regs, argcnt, true );
 701 }
 702 
 703 
 704 //------------------------------match------------------------------------------
 705 // Construct projections for control, I/O, memory-fields, ..., and
 706 // return result(s) along with their RegMask info
 707 Node *CallNode::match( const ProjNode *proj, const Matcher *match ) {
 708   switch (proj->_con) {
 709   case TypeFunc::Control:
 710   case TypeFunc::I_O:
 711   case TypeFunc::Memory:
 712     return new MachProjNode(this,proj->_con,RegMask::Empty,MachProjNode::unmatched_proj);
 713 
 714   case TypeFunc::Parms+1:       // For LONG & DOUBLE returns
 715     assert(tf()->range()->field_at(TypeFunc::Parms+1) == Type::HALF, "");
 716     // 2nd half of doubles and longs
 717     return new MachProjNode(this,proj->_con, RegMask::Empty, (uint)OptoReg::Bad);
 718 
 719   case TypeFunc::Parms: {       // Normal returns
 720     uint ideal_reg = tf()->range()->field_at(TypeFunc::Parms)->ideal_reg();
 721     OptoRegPair regs = is_CallRuntime()
 722       ? match->c_return_value(ideal_reg,true)  // Calls into C runtime
 723       : match->  return_value(ideal_reg,true); // Calls into compiled Java code
 724     RegMask rm = RegMask(regs.first());
 725     if( OptoReg::is_valid(regs.second()) )
 726       rm.Insert( regs.second() );
 727     return new MachProjNode(this,proj->_con,rm,ideal_reg);
 728   }
 729 
 730   case TypeFunc::ReturnAdr:
 731   case TypeFunc::FramePtr:
 732   default:
 733     ShouldNotReachHere();
 734   }
 735   return NULL;
 736 }
 737 
 738 // Do we Match on this edge index or not?  Match no edges
 739 uint CallNode::match_edge(uint idx) const {
 740   return 0;
 741 }
 742 
 743 //
 744 // Determine whether the call could modify the field of the specified
 745 // instance at the specified offset.
 746 //
 747 bool CallNode::may_modify(const TypeOopPtr *t_oop, PhaseTransform *phase) {
 748   assert((t_oop != NULL), "sanity");
 749   if (is_call_to_arraycopystub() && strcmp(_name, "unsafe_arraycopy") != 0) {
 750     const TypeTuple* args = _tf->domain();
 751     Node* dest = NULL;
 752     // Stubs that can be called once an ArrayCopyNode is expanded have
 753     // different signatures. Look for the second pointer argument,
 754     // that is the destination of the copy.
 755     for (uint i = TypeFunc::Parms, j = 0; i < args->cnt(); i++) {
 756       if (args->field_at(i)->isa_ptr()) {
 757         j++;
 758         if (j == 2) {
 759           dest = in(i);
 760           break;
 761         }
 762       }
 763     }
 764     guarantee(dest != NULL, "Call had only one ptr in, broken IR!");
 765     if (!dest->is_top() && may_modify_arraycopy_helper(phase->type(dest)->is_oopptr(), t_oop, phase)) {
 766       return true;
 767     }
 768     return false;
 769   }
 770   if (t_oop->is_known_instance()) {
 771     // The instance_id is set only for scalar-replaceable allocations which
 772     // are not passed as arguments according to Escape Analysis.
 773     return false;
 774   }
 775   if (t_oop->is_ptr_to_boxed_value()) {
 776     ciKlass* boxing_klass = t_oop->klass();
 777     if (is_CallStaticJava() && as_CallStaticJava()->is_boxing_method()) {
 778       // Skip unrelated boxing methods.
 779       Node* proj = proj_out_or_null(TypeFunc::Parms);
 780       if ((proj == NULL) || (phase->type(proj)->is_instptr()->klass() != boxing_klass)) {
 781         return false;
 782       }
 783     }
 784     if (is_CallJava() && as_CallJava()->method() != NULL) {
 785       ciMethod* meth = as_CallJava()->method();
 786       if (meth->is_getter()) {
 787         return false;
 788       }
 789       // May modify (by reflection) if an boxing object is passed
 790       // as argument or returned.
 791       Node* proj = returns_pointer() ? proj_out_or_null(TypeFunc::Parms) : NULL;
 792       if (proj != NULL) {
 793         const TypeInstPtr* inst_t = phase->type(proj)->isa_instptr();
 794         if ((inst_t != NULL) && (!inst_t->klass_is_exact() ||
 795                                  (inst_t->klass() == boxing_klass))) {
 796           return true;
 797         }
 798       }
 799       const TypeTuple* d = tf()->domain();
 800       for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
 801         const TypeInstPtr* inst_t = d->field_at(i)->isa_instptr();
 802         if ((inst_t != NULL) && (!inst_t->klass_is_exact() ||
 803                                  (inst_t->klass() == boxing_klass))) {
 804           return true;
 805         }
 806       }
 807       return false;
 808     }
 809   }
 810   return true;
 811 }
 812 
 813 // Does this call have a direct reference to n other than debug information?
 814 bool CallNode::has_non_debug_use(Node *n) {
 815   const TypeTuple * d = tf()->domain();
 816   for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
 817     Node *arg = in(i);
 818     if (arg == n) {
 819       return true;
 820     }
 821   }
 822   return false;
 823 }
 824 
 825 // Returns the unique CheckCastPP of a call
 826 // or 'this' if there are several CheckCastPP or unexpected uses
 827 // or returns NULL if there is no one.
 828 Node *CallNode::result_cast() {
 829   Node *cast = NULL;
 830 
 831   Node *p = proj_out_or_null(TypeFunc::Parms);
 832   if (p == NULL)
 833     return NULL;
 834 
 835   for (DUIterator_Fast imax, i = p->fast_outs(imax); i < imax; i++) {
 836     Node *use = p->fast_out(i);
 837     if (use->is_CheckCastPP()) {
 838       if (cast != NULL) {
 839         return this;  // more than 1 CheckCastPP
 840       }
 841       cast = use;
 842     } else if (!use->is_Initialize() &&
 843                !use->is_AddP() &&
 844                use->Opcode() != Op_MemBarStoreStore) {
 845       // Expected uses are restricted to a CheckCastPP, an Initialize
 846       // node, a MemBarStoreStore (clone) and AddP nodes. If we
 847       // encounter any other use (a Phi node can be seen in rare
 848       // cases) return this to prevent incorrect optimizations.
 849       return this;
 850     }
 851   }
 852   return cast;
 853 }
 854 
 855 
 856 void CallNode::extract_projections(CallProjections* projs, bool separate_io_proj, bool do_asserts) {
 857   projs->fallthrough_proj      = NULL;
 858   projs->fallthrough_catchproj = NULL;
 859   projs->fallthrough_ioproj    = NULL;
 860   projs->catchall_ioproj       = NULL;
 861   projs->catchall_catchproj    = NULL;
 862   projs->fallthrough_memproj   = NULL;
 863   projs->catchall_memproj      = NULL;
 864   projs->resproj               = NULL;
 865   projs->exobj                 = NULL;
 866 
 867   for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
 868     ProjNode *pn = fast_out(i)->as_Proj();
 869     if (pn->outcnt() == 0) continue;
 870     switch (pn->_con) {
 871     case TypeFunc::Control:
 872       {
 873         // For Control (fallthrough) and I_O (catch_all_index) we have CatchProj -> Catch -> Proj
 874         projs->fallthrough_proj = pn;
 875         DUIterator_Fast jmax, j = pn->fast_outs(jmax);
 876         const Node *cn = pn->fast_out(j);
 877         if (cn->is_Catch()) {
 878           ProjNode *cpn = NULL;
 879           for (DUIterator_Fast kmax, k = cn->fast_outs(kmax); k < kmax; k++) {
 880             cpn = cn->fast_out(k)->as_Proj();
 881             assert(cpn->is_CatchProj(), "must be a CatchProjNode");
 882             if (cpn->_con == CatchProjNode::fall_through_index)
 883               projs->fallthrough_catchproj = cpn;
 884             else {
 885               assert(cpn->_con == CatchProjNode::catch_all_index, "must be correct index.");
 886               projs->catchall_catchproj = cpn;
 887             }
 888           }
 889         }
 890         break;
 891       }
 892     case TypeFunc::I_O:
 893       if (pn->_is_io_use)
 894         projs->catchall_ioproj = pn;
 895       else
 896         projs->fallthrough_ioproj = pn;
 897       for (DUIterator j = pn->outs(); pn->has_out(j); j++) {
 898         Node* e = pn->out(j);
 899         if (e->Opcode() == Op_CreateEx && e->in(0)->is_CatchProj() && e->outcnt() > 0) {
 900           assert(projs->exobj == NULL, "only one");
 901           projs->exobj = e;
 902         }
 903       }
 904       break;
 905     case TypeFunc::Memory:
 906       if (pn->_is_io_use)
 907         projs->catchall_memproj = pn;
 908       else
 909         projs->fallthrough_memproj = pn;
 910       break;
 911     case TypeFunc::Parms:
 912       projs->resproj = pn;
 913       break;
 914     default:
 915       assert(false, "unexpected projection from allocation node.");
 916     }
 917   }
 918 
 919   // The resproj may not exist because the result could be ignored
 920   // and the exception object may not exist if an exception handler
 921   // swallows the exception but all the other must exist and be found.
 922   assert(projs->fallthrough_proj      != NULL, "must be found");
 923   do_asserts = do_asserts && !Compile::current()->inlining_incrementally();
 924   assert(!do_asserts || projs->fallthrough_catchproj != NULL, "must be found");
 925   assert(!do_asserts || projs->fallthrough_memproj   != NULL, "must be found");
 926   assert(!do_asserts || projs->fallthrough_ioproj    != NULL, "must be found");
 927   assert(!do_asserts || projs->catchall_catchproj    != NULL, "must be found");
 928   if (separate_io_proj) {
 929     assert(!do_asserts || projs->catchall_memproj    != NULL, "must be found");
 930     assert(!do_asserts || projs->catchall_ioproj     != NULL, "must be found");
 931   }
 932 }
 933 
 934 Node *CallNode::Ideal(PhaseGVN *phase, bool can_reshape) {
 935   CallGenerator* cg = generator();
 936   if (can_reshape && cg != NULL && cg->is_mh_late_inline() && !cg->already_attempted()) {
 937     // Check whether this MH handle call becomes a candidate for inlining
 938     ciMethod* callee = cg->method();
 939     vmIntrinsics::ID iid = callee->intrinsic_id();
 940     if (iid == vmIntrinsics::_invokeBasic) {
 941       if (in(TypeFunc::Parms)->Opcode() == Op_ConP) {
 942         phase->C->prepend_late_inline(cg);
 943         set_generator(NULL);
 944       }
 945     } else {
 946       assert(callee->has_member_arg(), "wrong type of call?");
 947       if (in(TypeFunc::Parms + callee->arg_size() - 1)->Opcode() == Op_ConP) {
 948         phase->C->prepend_late_inline(cg);
 949         set_generator(NULL);
 950       }
 951     }
 952   }
 953   return SafePointNode::Ideal(phase, can_reshape);
 954 }
 955 
 956 bool CallNode::is_call_to_arraycopystub() const {
 957   if (_name != NULL && strstr(_name, "arraycopy") != 0) {
 958     return true;
 959   }
 960   return false;
 961 }
 962 
 963 //=============================================================================
 964 uint CallJavaNode::size_of() const { return sizeof(*this); }
 965 uint CallJavaNode::cmp( const Node &n ) const {
 966   CallJavaNode &call = (CallJavaNode&)n;
 967   return CallNode::cmp(call) && _method == call._method &&
 968          _override_symbolic_info == call._override_symbolic_info;
 969 }
 970 #ifdef ASSERT
 971 bool CallJavaNode::validate_symbolic_info() const {
 972   if (method() == NULL) {
 973     return true; // call into runtime or uncommon trap
 974   }
 975   ciMethod* symbolic_info = jvms()->method()->get_method_at_bci(_bci);
 976   ciMethod* callee = method();
 977   if (symbolic_info->is_method_handle_intrinsic() && !callee->is_method_handle_intrinsic()) {
 978     assert(override_symbolic_info(), "should be set");
 979   }
 980   assert(ciMethod::is_consistent_info(symbolic_info, callee), "inconsistent info");
 981   return true;
 982 }
 983 #endif
 984 
 985 #ifndef PRODUCT
 986 void CallJavaNode::dump_spec(outputStream *st) const {
 987   if( _method ) _method->print_short_name(st);
 988   CallNode::dump_spec(st);
 989 }
 990 
 991 void CallJavaNode::dump_compact_spec(outputStream* st) const {
 992   if (_method) {
 993     _method->print_short_name(st);
 994   } else {
 995     st->print("<?>");
 996   }
 997 }
 998 #endif
 999 
1000 //=============================================================================
1001 uint CallStaticJavaNode::size_of() const { return sizeof(*this); }
1002 uint CallStaticJavaNode::cmp( const Node &n ) const {
1003   CallStaticJavaNode &call = (CallStaticJavaNode&)n;
1004   return CallJavaNode::cmp(call);
1005 }
1006 
1007 //----------------------------uncommon_trap_request----------------------------
1008 // If this is an uncommon trap, return the request code, else zero.
1009 int CallStaticJavaNode::uncommon_trap_request() const {
1010   if (_name != NULL && !strcmp(_name, "uncommon_trap")) {
1011     return extract_uncommon_trap_request(this);
1012   }
1013   return 0;
1014 }
1015 int CallStaticJavaNode::extract_uncommon_trap_request(const Node* call) {
1016 #ifndef PRODUCT
1017   if (!(call->req() > TypeFunc::Parms &&
1018         call->in(TypeFunc::Parms) != NULL &&
1019         call->in(TypeFunc::Parms)->is_Con() &&
1020         call->in(TypeFunc::Parms)->bottom_type()->isa_int())) {
1021     assert(in_dump() != 0, "OK if dumping");
1022     tty->print("[bad uncommon trap]");
1023     return 0;
1024   }
1025 #endif
1026   return call->in(TypeFunc::Parms)->bottom_type()->is_int()->get_con();
1027 }
1028 
1029 #ifndef PRODUCT
1030 void CallStaticJavaNode::dump_spec(outputStream *st) const {
1031   st->print("# Static ");
1032   if (_name != NULL) {
1033     st->print("%s", _name);
1034     int trap_req = uncommon_trap_request();
1035     if (trap_req != 0) {
1036       char buf[100];
1037       st->print("(%s)",
1038                  Deoptimization::format_trap_request(buf, sizeof(buf),
1039                                                      trap_req));
1040     }
1041     st->print(" ");
1042   }
1043   CallJavaNode::dump_spec(st);
1044 }
1045 
1046 void CallStaticJavaNode::dump_compact_spec(outputStream* st) const {
1047   if (_method) {
1048     _method->print_short_name(st);
1049   } else if (_name) {
1050     st->print("%s", _name);
1051   } else {
1052     st->print("<?>");
1053   }
1054 }
1055 #endif
1056 
1057 //=============================================================================
1058 uint CallDynamicJavaNode::size_of() const { return sizeof(*this); }
1059 uint CallDynamicJavaNode::cmp( const Node &n ) const {
1060   CallDynamicJavaNode &call = (CallDynamicJavaNode&)n;
1061   return CallJavaNode::cmp(call);
1062 }
1063 #ifndef PRODUCT
1064 void CallDynamicJavaNode::dump_spec(outputStream *st) const {
1065   st->print("# Dynamic ");
1066   CallJavaNode::dump_spec(st);
1067 }
1068 #endif
1069 
1070 //=============================================================================
1071 uint CallRuntimeNode::size_of() const { return sizeof(*this); }
1072 uint CallRuntimeNode::cmp( const Node &n ) const {
1073   CallRuntimeNode &call = (CallRuntimeNode&)n;
1074   return CallNode::cmp(call) && !strcmp(_name,call._name);
1075 }
1076 #ifndef PRODUCT
1077 void CallRuntimeNode::dump_spec(outputStream *st) const {
1078   st->print("# ");
1079   st->print("%s", _name);
1080   CallNode::dump_spec(st);
1081 }
1082 #endif
1083 
1084 //------------------------------calling_convention-----------------------------
1085 void CallRuntimeNode::calling_convention( BasicType* sig_bt, VMRegPair *parm_regs, uint argcnt ) const {
1086   Matcher::c_calling_convention( sig_bt, parm_regs, argcnt );
1087 }
1088 
1089 //=============================================================================
1090 //------------------------------calling_convention-----------------------------
1091 
1092 
1093 //=============================================================================
1094 #ifndef PRODUCT
1095 void CallLeafNode::dump_spec(outputStream *st) const {
1096   st->print("# ");
1097   st->print("%s", _name);
1098   CallNode::dump_spec(st);
1099 }
1100 #endif
1101 
1102 //=============================================================================
1103 
1104 void SafePointNode::set_local(JVMState* jvms, uint idx, Node *c) {
1105   assert(verify_jvms(jvms), "jvms must match");
1106   int loc = jvms->locoff() + idx;
1107   if (in(loc)->is_top() && idx > 0 && !c->is_top() ) {
1108     // If current local idx is top then local idx - 1 could
1109     // be a long/double that needs to be killed since top could
1110     // represent the 2nd half ofthe long/double.
1111     uint ideal = in(loc -1)->ideal_reg();
1112     if (ideal == Op_RegD || ideal == Op_RegL) {
1113       // set other (low index) half to top
1114       set_req(loc - 1, in(loc));
1115     }
1116   }
1117   set_req(loc, c);
1118 }
1119 
1120 uint SafePointNode::size_of() const { return sizeof(*this); }
1121 uint SafePointNode::cmp( const Node &n ) const {
1122   return (&n == this);          // Always fail except on self
1123 }
1124 
1125 //-------------------------set_next_exception----------------------------------
1126 void SafePointNode::set_next_exception(SafePointNode* n) {
1127   assert(n == NULL || n->Opcode() == Op_SafePoint, "correct value for next_exception");
1128   if (len() == req()) {
1129     if (n != NULL)  add_prec(n);
1130   } else {
1131     set_prec(req(), n);
1132   }
1133 }
1134 
1135 
1136 //----------------------------next_exception-----------------------------------
1137 SafePointNode* SafePointNode::next_exception() const {
1138   if (len() == req()) {
1139     return NULL;
1140   } else {
1141     Node* n = in(req());
1142     assert(n == NULL || n->Opcode() == Op_SafePoint, "no other uses of prec edges");
1143     return (SafePointNode*) n;
1144   }
1145 }
1146 
1147 
1148 //------------------------------Ideal------------------------------------------
1149 // Skip over any collapsed Regions
1150 Node *SafePointNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1151   return remove_dead_region(phase, can_reshape) ? this : NULL;
1152 }
1153 
1154 //------------------------------Identity---------------------------------------
1155 // Remove obviously duplicate safepoints
1156 Node* SafePointNode::Identity(PhaseGVN* phase) {
1157 
1158   // If you have back to back safepoints, remove one
1159   if( in(TypeFunc::Control)->is_SafePoint() )
1160     return in(TypeFunc::Control);
1161 
1162   if( in(0)->is_Proj() ) {
1163     Node *n0 = in(0)->in(0);
1164     // Check if he is a call projection (except Leaf Call)
1165     if( n0->is_Catch() ) {
1166       n0 = n0->in(0)->in(0);
1167       assert( n0->is_Call(), "expect a call here" );
1168     }
1169     if( n0->is_Call() && n0->as_Call()->guaranteed_safepoint() ) {
1170       // Don't remove a safepoint belonging to an OuterStripMinedLoopEndNode.
1171       // If the loop dies, they will be removed together.
1172       if (has_out_with(Op_OuterStripMinedLoopEnd)) {
1173         return this;
1174       }
1175       // Useless Safepoint, so remove it
1176       return in(TypeFunc::Control);
1177     }
1178   }
1179 
1180   return this;
1181 }
1182 
1183 //------------------------------Value------------------------------------------
1184 const Type* SafePointNode::Value(PhaseGVN* phase) const {
1185   if( phase->type(in(0)) == Type::TOP ) return Type::TOP;
1186   if( phase->eqv( in(0), this ) ) return Type::TOP; // Dead infinite loop
1187   return Type::CONTROL;
1188 }
1189 
1190 #ifndef PRODUCT
1191 void SafePointNode::dump_spec(outputStream *st) const {
1192   st->print(" SafePoint ");
1193   _replaced_nodes.dump(st);
1194 }
1195 
1196 // The related nodes of a SafepointNode are all data inputs, excluding the
1197 // control boundary, as well as all outputs till level 2 (to include projection
1198 // nodes and targets). In compact mode, just include inputs till level 1 and
1199 // outputs as before.
1200 void SafePointNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
1201   if (compact) {
1202     this->collect_nodes(in_rel, 1, false, false);
1203   } else {
1204     this->collect_nodes_in_all_data(in_rel, false);
1205   }
1206   this->collect_nodes(out_rel, -2, false, false);
1207 }
1208 #endif
1209 
1210 const RegMask &SafePointNode::in_RegMask(uint idx) const {
1211   if( idx < TypeFunc::Parms ) return RegMask::Empty;
1212   // Values outside the domain represent debug info
1213   return *(Compile::current()->matcher()->idealreg2debugmask[in(idx)->ideal_reg()]);
1214 }
1215 const RegMask &SafePointNode::out_RegMask() const {
1216   return RegMask::Empty;
1217 }
1218 
1219 
1220 void SafePointNode::grow_stack(JVMState* jvms, uint grow_by) {
1221   assert((int)grow_by > 0, "sanity");
1222   int monoff = jvms->monoff();
1223   int scloff = jvms->scloff();
1224   int endoff = jvms->endoff();
1225   assert(endoff == (int)req(), "no other states or debug info after me");
1226   Node* top = Compile::current()->top();
1227   for (uint i = 0; i < grow_by; i++) {
1228     ins_req(monoff, top);
1229   }
1230   jvms->set_monoff(monoff + grow_by);
1231   jvms->set_scloff(scloff + grow_by);
1232   jvms->set_endoff(endoff + grow_by);
1233 }
1234 
1235 void SafePointNode::push_monitor(const FastLockNode *lock) {
1236   // Add a LockNode, which points to both the original BoxLockNode (the
1237   // stack space for the monitor) and the Object being locked.
1238   const int MonitorEdges = 2;
1239   assert(JVMState::logMonitorEdges == exact_log2(MonitorEdges), "correct MonitorEdges");
1240   assert(req() == jvms()->endoff(), "correct sizing");
1241   int nextmon = jvms()->scloff();
1242   if (GenerateSynchronizationCode) {
1243     ins_req(nextmon,   lock->box_node());
1244     ins_req(nextmon+1, lock->obj_node());
1245   } else {
1246     Node* top = Compile::current()->top();
1247     ins_req(nextmon, top);
1248     ins_req(nextmon, top);
1249   }
1250   jvms()->set_scloff(nextmon + MonitorEdges);
1251   jvms()->set_endoff(req());
1252 }
1253 
1254 void SafePointNode::pop_monitor() {
1255   // Delete last monitor from debug info
1256   debug_only(int num_before_pop = jvms()->nof_monitors());
1257   const int MonitorEdges = 2;
1258   assert(JVMState::logMonitorEdges == exact_log2(MonitorEdges), "correct MonitorEdges");
1259   int scloff = jvms()->scloff();
1260   int endoff = jvms()->endoff();
1261   int new_scloff = scloff - MonitorEdges;
1262   int new_endoff = endoff - MonitorEdges;
1263   jvms()->set_scloff(new_scloff);
1264   jvms()->set_endoff(new_endoff);
1265   while (scloff > new_scloff)  del_req_ordered(--scloff);
1266   assert(jvms()->nof_monitors() == num_before_pop-1, "");
1267 }
1268 
1269 Node *SafePointNode::peek_monitor_box() const {
1270   int mon = jvms()->nof_monitors() - 1;
1271   assert(mon >= 0, "must have a monitor");
1272   return monitor_box(jvms(), mon);
1273 }
1274 
1275 Node *SafePointNode::peek_monitor_obj() const {
1276   int mon = jvms()->nof_monitors() - 1;
1277   assert(mon >= 0, "must have a monitor");
1278   return monitor_obj(jvms(), mon);
1279 }
1280 
1281 // Do we Match on this edge index or not?  Match no edges
1282 uint SafePointNode::match_edge(uint idx) const {
1283   if( !needs_polling_address_input() )
1284     return 0;
1285 
1286   return (TypeFunc::Parms == idx);
1287 }
1288 
1289 //==============  SafePointScalarObjectNode  ==============
1290 
1291 SafePointScalarObjectNode::SafePointScalarObjectNode(const TypeOopPtr* tp,
1292 #ifdef ASSERT
1293                                                      AllocateNode* alloc,
1294 #endif
1295                                                      uint first_index,
1296                                                      uint n_fields) :
1297   TypeNode(tp, 1), // 1 control input -- seems required.  Get from root.
1298 #ifdef ASSERT
1299   _alloc(alloc),
1300 #endif
1301   _first_index(first_index),
1302   _n_fields(n_fields)
1303 {
1304   init_class_id(Class_SafePointScalarObject);
1305 }
1306 
1307 // Do not allow value-numbering for SafePointScalarObject node.
1308 uint SafePointScalarObjectNode::hash() const { return NO_HASH; }
1309 uint SafePointScalarObjectNode::cmp( const Node &n ) const {
1310   return (&n == this); // Always fail except on self
1311 }
1312 
1313 uint SafePointScalarObjectNode::ideal_reg() const {
1314   return 0; // No matching to machine instruction
1315 }
1316 
1317 const RegMask &SafePointScalarObjectNode::in_RegMask(uint idx) const {
1318   return *(Compile::current()->matcher()->idealreg2debugmask[in(idx)->ideal_reg()]);
1319 }
1320 
1321 const RegMask &SafePointScalarObjectNode::out_RegMask() const {
1322   return RegMask::Empty;
1323 }
1324 
1325 uint SafePointScalarObjectNode::match_edge(uint idx) const {
1326   return 0;
1327 }
1328 
1329 SafePointScalarObjectNode*
1330 SafePointScalarObjectNode::clone(Dict* sosn_map) const {
1331   void* cached = (*sosn_map)[(void*)this];
1332   if (cached != NULL) {
1333     return (SafePointScalarObjectNode*)cached;
1334   }
1335   SafePointScalarObjectNode* res = (SafePointScalarObjectNode*)Node::clone();
1336   sosn_map->Insert((void*)this, (void*)res);
1337   return res;
1338 }
1339 
1340 
1341 #ifndef PRODUCT
1342 void SafePointScalarObjectNode::dump_spec(outputStream *st) const {
1343   st->print(" # fields@[%d..%d]", first_index(),
1344              first_index() + n_fields() - 1);
1345 }
1346 
1347 #endif
1348 
1349 //=============================================================================
1350 uint AllocateNode::size_of() const { return sizeof(*this); }
1351 
1352 AllocateNode::AllocateNode(Compile* C, const TypeFunc *atype,
1353                            Node *ctrl, Node *mem, Node *abio,
1354                            Node *size, Node *klass_node, Node *initial_test)
1355   : CallNode(atype, NULL, TypeRawPtr::BOTTOM)
1356 {
1357   init_class_id(Class_Allocate);
1358   init_flags(Flag_is_macro);
1359   _is_scalar_replaceable = false;
1360   _is_non_escaping = false;
1361   _is_allocation_MemBar_redundant = false;
1362   Node *topnode = C->top();
1363 
1364   init_req( TypeFunc::Control  , ctrl );
1365   init_req( TypeFunc::I_O      , abio );
1366   init_req( TypeFunc::Memory   , mem );
1367   init_req( TypeFunc::ReturnAdr, topnode );
1368   init_req( TypeFunc::FramePtr , topnode );
1369   init_req( AllocSize          , size);
1370   init_req( KlassNode          , klass_node);
1371   init_req( InitialTest        , initial_test);
1372   init_req( ALength            , topnode);
1373   C->add_macro_node(this);
1374 }
1375 
1376 void AllocateNode::compute_MemBar_redundancy(ciMethod* initializer)
1377 {
1378   assert(initializer != NULL &&
1379          initializer->is_initializer() &&
1380          !initializer->is_static(),
1381              "unexpected initializer method");
1382   BCEscapeAnalyzer* analyzer = initializer->get_bcea();
1383   if (analyzer == NULL) {
1384     return;
1385   }
1386 
1387   // Allocation node is first parameter in its initializer
1388   if (analyzer->is_arg_stack(0) || analyzer->is_arg_local(0)) {
1389     _is_allocation_MemBar_redundant = true;
1390   }
1391 }
1392 
1393 //=============================================================================
1394 Node* AllocateArrayNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1395   if (remove_dead_region(phase, can_reshape))  return this;
1396   // Don't bother trying to transform a dead node
1397   if (in(0) && in(0)->is_top())  return NULL;
1398 
1399   const Type* type = phase->type(Ideal_length());
1400   if (type->isa_int() && type->is_int()->_hi < 0) {
1401     if (can_reshape) {
1402       PhaseIterGVN *igvn = phase->is_IterGVN();
1403       // Unreachable fall through path (negative array length),
1404       // the allocation can only throw so disconnect it.
1405       Node* proj = proj_out_or_null(TypeFunc::Control);
1406       Node* catchproj = NULL;
1407       if (proj != NULL) {
1408         for (DUIterator_Fast imax, i = proj->fast_outs(imax); i < imax; i++) {
1409           Node *cn = proj->fast_out(i);
1410           if (cn->is_Catch()) {
1411             catchproj = cn->as_Multi()->proj_out_or_null(CatchProjNode::fall_through_index);
1412             break;
1413           }
1414         }
1415       }
1416       if (catchproj != NULL && catchproj->outcnt() > 0 &&
1417           (catchproj->outcnt() > 1 ||
1418            catchproj->unique_out()->Opcode() != Op_Halt)) {
1419         assert(catchproj->is_CatchProj(), "must be a CatchProjNode");
1420         Node* nproj = catchproj->clone();
1421         igvn->register_new_node_with_optimizer(nproj);
1422 
1423         Node *frame = new ParmNode( phase->C->start(), TypeFunc::FramePtr );
1424         frame = phase->transform(frame);
1425         // Halt & Catch Fire
1426         Node *halt = new HaltNode( nproj, frame );
1427         phase->C->root()->add_req(halt);
1428         phase->transform(halt);
1429 
1430         igvn->replace_node(catchproj, phase->C->top());
1431         return this;
1432       }
1433     } else {
1434       // Can't correct it during regular GVN so register for IGVN
1435       phase->C->record_for_igvn(this);
1436     }
1437   }
1438   return NULL;
1439 }
1440 
1441 // Retrieve the length from the AllocateArrayNode. Narrow the type with a
1442 // CastII, if appropriate.  If we are not allowed to create new nodes, and
1443 // a CastII is appropriate, return NULL.
1444 Node *AllocateArrayNode::make_ideal_length(const TypeOopPtr* oop_type, PhaseTransform *phase, bool allow_new_nodes) {
1445   Node *length = in(AllocateNode::ALength);
1446   assert(length != NULL, "length is not null");
1447 
1448   const TypeInt* length_type = phase->find_int_type(length);
1449   const TypeAryPtr* ary_type = oop_type->isa_aryptr();
1450 
1451   if (ary_type != NULL && length_type != NULL) {
1452     const TypeInt* narrow_length_type = ary_type->narrow_size_type(length_type);
1453     if (narrow_length_type != length_type) {
1454       // Assert one of:
1455       //   - the narrow_length is 0
1456       //   - the narrow_length is not wider than length
1457       assert(narrow_length_type == TypeInt::ZERO ||
1458              length_type->is_con() && narrow_length_type->is_con() &&
1459                 (narrow_length_type->_hi <= length_type->_lo) ||
1460              (narrow_length_type->_hi <= length_type->_hi &&
1461               narrow_length_type->_lo >= length_type->_lo),
1462              "narrow type must be narrower than length type");
1463 
1464       // Return NULL if new nodes are not allowed
1465       if (!allow_new_nodes) return NULL;
1466       // Create a cast which is control dependent on the initialization to
1467       // propagate the fact that the array length must be positive.
1468       InitializeNode* init = initialization();
1469       assert(init != NULL, "initialization not found");
1470       length = new CastIINode(length, narrow_length_type);
1471       length->set_req(0, init->proj_out_or_null(0));
1472     }
1473   }
1474 
1475   return length;
1476 }
1477 
1478 //=============================================================================
1479 uint LockNode::size_of() const { return sizeof(*this); }
1480 
1481 // Redundant lock elimination
1482 //
1483 // There are various patterns of locking where we release and
1484 // immediately reacquire a lock in a piece of code where no operations
1485 // occur in between that would be observable.  In those cases we can
1486 // skip releasing and reacquiring the lock without violating any
1487 // fairness requirements.  Doing this around a loop could cause a lock
1488 // to be held for a very long time so we concentrate on non-looping
1489 // control flow.  We also require that the operations are fully
1490 // redundant meaning that we don't introduce new lock operations on
1491 // some paths so to be able to eliminate it on others ala PRE.  This
1492 // would probably require some more extensive graph manipulation to
1493 // guarantee that the memory edges were all handled correctly.
1494 //
1495 // Assuming p is a simple predicate which can't trap in any way and s
1496 // is a synchronized method consider this code:
1497 //
1498 //   s();
1499 //   if (p)
1500 //     s();
1501 //   else
1502 //     s();
1503 //   s();
1504 //
1505 // 1. The unlocks of the first call to s can be eliminated if the
1506 // locks inside the then and else branches are eliminated.
1507 //
1508 // 2. The unlocks of the then and else branches can be eliminated if
1509 // the lock of the final call to s is eliminated.
1510 //
1511 // Either of these cases subsumes the simple case of sequential control flow
1512 //
1513 // Addtionally we can eliminate versions without the else case:
1514 //
1515 //   s();
1516 //   if (p)
1517 //     s();
1518 //   s();
1519 //
1520 // 3. In this case we eliminate the unlock of the first s, the lock
1521 // and unlock in the then case and the lock in the final s.
1522 //
1523 // Note also that in all these cases the then/else pieces don't have
1524 // to be trivial as long as they begin and end with synchronization
1525 // operations.
1526 //
1527 //   s();
1528 //   if (p)
1529 //     s();
1530 //     f();
1531 //     s();
1532 //   s();
1533 //
1534 // The code will work properly for this case, leaving in the unlock
1535 // before the call to f and the relock after it.
1536 //
1537 // A potentially interesting case which isn't handled here is when the
1538 // locking is partially redundant.
1539 //
1540 //   s();
1541 //   if (p)
1542 //     s();
1543 //
1544 // This could be eliminated putting unlocking on the else case and
1545 // eliminating the first unlock and the lock in the then side.
1546 // Alternatively the unlock could be moved out of the then side so it
1547 // was after the merge and the first unlock and second lock
1548 // eliminated.  This might require less manipulation of the memory
1549 // state to get correct.
1550 //
1551 // Additionally we might allow work between a unlock and lock before
1552 // giving up eliminating the locks.  The current code disallows any
1553 // conditional control flow between these operations.  A formulation
1554 // similar to partial redundancy elimination computing the
1555 // availability of unlocking and the anticipatability of locking at a
1556 // program point would allow detection of fully redundant locking with
1557 // some amount of work in between.  I'm not sure how often I really
1558 // think that would occur though.  Most of the cases I've seen
1559 // indicate it's likely non-trivial work would occur in between.
1560 // There may be other more complicated constructs where we could
1561 // eliminate locking but I haven't seen any others appear as hot or
1562 // interesting.
1563 //
1564 // Locking and unlocking have a canonical form in ideal that looks
1565 // roughly like this:
1566 //
1567 //              <obj>
1568 //                | \\------+
1569 //                |  \       \
1570 //                | BoxLock   \
1571 //                |  |   |     \
1572 //                |  |    \     \
1573 //                |  |   FastLock
1574 //                |  |   /
1575 //                |  |  /
1576 //                |  |  |
1577 //
1578 //               Lock
1579 //                |
1580 //            Proj #0
1581 //                |
1582 //            MembarAcquire
1583 //                |
1584 //            Proj #0
1585 //
1586 //            MembarRelease
1587 //                |
1588 //            Proj #0
1589 //                |
1590 //              Unlock
1591 //                |
1592 //            Proj #0
1593 //
1594 //
1595 // This code proceeds by processing Lock nodes during PhaseIterGVN
1596 // and searching back through its control for the proper code
1597 // patterns.  Once it finds a set of lock and unlock operations to
1598 // eliminate they are marked as eliminatable which causes the
1599 // expansion of the Lock and Unlock macro nodes to make the operation a NOP
1600 //
1601 //=============================================================================
1602 
1603 //
1604 // Utility function to skip over uninteresting control nodes.  Nodes skipped are:
1605 //   - copy regions.  (These may not have been optimized away yet.)
1606 //   - eliminated locking nodes
1607 //
1608 static Node *next_control(Node *ctrl) {
1609   if (ctrl == NULL)
1610     return NULL;
1611   while (1) {
1612     if (ctrl->is_Region()) {
1613       RegionNode *r = ctrl->as_Region();
1614       Node *n = r->is_copy();
1615       if (n == NULL)
1616         break;  // hit a region, return it
1617       else
1618         ctrl = n;
1619     } else if (ctrl->is_Proj()) {
1620       Node *in0 = ctrl->in(0);
1621       if (in0->is_AbstractLock() && in0->as_AbstractLock()->is_eliminated()) {
1622         ctrl = in0->in(0);
1623       } else {
1624         break;
1625       }
1626     } else {
1627       break; // found an interesting control
1628     }
1629   }
1630   return ctrl;
1631 }
1632 //
1633 // Given a control, see if it's the control projection of an Unlock which
1634 // operating on the same object as lock.
1635 //
1636 bool AbstractLockNode::find_matching_unlock(const Node* ctrl, LockNode* lock,
1637                                             GrowableArray<AbstractLockNode*> &lock_ops) {
1638   ProjNode *ctrl_proj = (ctrl->is_Proj()) ? ctrl->as_Proj() : NULL;
1639   if (ctrl_proj != NULL && ctrl_proj->_con == TypeFunc::Control) {
1640     Node *n = ctrl_proj->in(0);
1641     if (n != NULL && n->is_Unlock()) {
1642       UnlockNode *unlock = n->as_Unlock();
1643       BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1644       Node* lock_obj = bs->step_over_gc_barrier(lock->obj_node());
1645       Node* unlock_obj = bs->step_over_gc_barrier(unlock->obj_node());
1646       if (lock_obj->eqv_uncast(unlock_obj) &&
1647           BoxLockNode::same_slot(lock->box_node(), unlock->box_node()) &&
1648           !unlock->is_eliminated()) {
1649         lock_ops.append(unlock);
1650         return true;
1651       }
1652     }
1653   }
1654   return false;
1655 }
1656 
1657 //
1658 // Find the lock matching an unlock.  Returns null if a safepoint
1659 // or complicated control is encountered first.
1660 LockNode *AbstractLockNode::find_matching_lock(UnlockNode* unlock) {
1661   LockNode *lock_result = NULL;
1662   // find the matching lock, or an intervening safepoint
1663   Node *ctrl = next_control(unlock->in(0));
1664   while (1) {
1665     assert(ctrl != NULL, "invalid control graph");
1666     assert(!ctrl->is_Start(), "missing lock for unlock");
1667     if (ctrl->is_top()) break;  // dead control path
1668     if (ctrl->is_Proj()) ctrl = ctrl->in(0);
1669     if (ctrl->is_SafePoint()) {
1670         break;  // found a safepoint (may be the lock we are searching for)
1671     } else if (ctrl->is_Region()) {
1672       // Check for a simple diamond pattern.  Punt on anything more complicated
1673       if (ctrl->req() == 3 && ctrl->in(1) != NULL && ctrl->in(2) != NULL) {
1674         Node *in1 = next_control(ctrl->in(1));
1675         Node *in2 = next_control(ctrl->in(2));
1676         if (((in1->is_IfTrue() && in2->is_IfFalse()) ||
1677              (in2->is_IfTrue() && in1->is_IfFalse())) && (in1->in(0) == in2->in(0))) {
1678           ctrl = next_control(in1->in(0)->in(0));
1679         } else {
1680           break;
1681         }
1682       } else {
1683         break;
1684       }
1685     } else {
1686       ctrl = next_control(ctrl->in(0));  // keep searching
1687     }
1688   }
1689   if (ctrl->is_Lock()) {
1690     LockNode *lock = ctrl->as_Lock();
1691     BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1692     Node* lock_obj = bs->step_over_gc_barrier(lock->obj_node());
1693     Node* unlock_obj = bs->step_over_gc_barrier(unlock->obj_node());
1694     if (lock_obj->eqv_uncast(unlock_obj) &&
1695         BoxLockNode::same_slot(lock->box_node(), unlock->box_node())) {
1696       lock_result = lock;
1697     }
1698   }
1699   return lock_result;
1700 }
1701 
1702 // This code corresponds to case 3 above.
1703 
1704 bool AbstractLockNode::find_lock_and_unlock_through_if(Node* node, LockNode* lock,
1705                                                        GrowableArray<AbstractLockNode*> &lock_ops) {
1706   Node* if_node = node->in(0);
1707   bool  if_true = node->is_IfTrue();
1708 
1709   if (if_node->is_If() && if_node->outcnt() == 2 && (if_true || node->is_IfFalse())) {
1710     Node *lock_ctrl = next_control(if_node->in(0));
1711     if (find_matching_unlock(lock_ctrl, lock, lock_ops)) {
1712       Node* lock1_node = NULL;
1713       ProjNode* proj = if_node->as_If()->proj_out(!if_true);
1714       if (if_true) {
1715         if (proj->is_IfFalse() && proj->outcnt() == 1) {
1716           lock1_node = proj->unique_out();
1717         }
1718       } else {
1719         if (proj->is_IfTrue() && proj->outcnt() == 1) {
1720           lock1_node = proj->unique_out();
1721         }
1722       }
1723       if (lock1_node != NULL && lock1_node->is_Lock()) {
1724         LockNode *lock1 = lock1_node->as_Lock();
1725         BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1726         Node* lock_obj = bs->step_over_gc_barrier(lock->obj_node());
1727         Node* lock1_obj = bs->step_over_gc_barrier(lock1->obj_node());
1728         if (lock_obj->eqv_uncast(lock1_obj) &&
1729             BoxLockNode::same_slot(lock->box_node(), lock1->box_node()) &&
1730             !lock1->is_eliminated()) {
1731           lock_ops.append(lock1);
1732           return true;
1733         }
1734       }
1735     }
1736   }
1737 
1738   lock_ops.trunc_to(0);
1739   return false;
1740 }
1741 
1742 bool AbstractLockNode::find_unlocks_for_region(const RegionNode* region, LockNode* lock,
1743                                GrowableArray<AbstractLockNode*> &lock_ops) {
1744   // check each control merging at this point for a matching unlock.
1745   // in(0) should be self edge so skip it.
1746   for (int i = 1; i < (int)region->req(); i++) {
1747     Node *in_node = next_control(region->in(i));
1748     if (in_node != NULL) {
1749       if (find_matching_unlock(in_node, lock, lock_ops)) {
1750         // found a match so keep on checking.
1751         continue;
1752       } else if (find_lock_and_unlock_through_if(in_node, lock, lock_ops)) {
1753         continue;
1754       }
1755 
1756       // If we fall through to here then it was some kind of node we
1757       // don't understand or there wasn't a matching unlock, so give
1758       // up trying to merge locks.
1759       lock_ops.trunc_to(0);
1760       return false;
1761     }
1762   }
1763   return true;
1764 
1765 }
1766 
1767 #ifndef PRODUCT
1768 //
1769 // Create a counter which counts the number of times this lock is acquired
1770 //
1771 void AbstractLockNode::create_lock_counter(JVMState* state) {
1772   _counter = OptoRuntime::new_named_counter(state, NamedCounter::LockCounter);
1773 }
1774 
1775 void AbstractLockNode::set_eliminated_lock_counter() {
1776   if (_counter) {
1777     // Update the counter to indicate that this lock was eliminated.
1778     // The counter update code will stay around even though the
1779     // optimizer will eliminate the lock operation itself.
1780     _counter->set_tag(NamedCounter::EliminatedLockCounter);
1781   }
1782 }
1783 
1784 const char* AbstractLockNode::_kind_names[] = {"Regular", "NonEscObj", "Coarsened", "Nested"};
1785 
1786 void AbstractLockNode::dump_spec(outputStream* st) const {
1787   st->print("%s ", _kind_names[_kind]);
1788   CallNode::dump_spec(st);
1789 }
1790 
1791 void AbstractLockNode::dump_compact_spec(outputStream* st) const {
1792   st->print("%s", _kind_names[_kind]);
1793 }
1794 
1795 // The related set of lock nodes includes the control boundary.
1796 void AbstractLockNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
1797   if (compact) {
1798       this->collect_nodes(in_rel, 1, false, false);
1799     } else {
1800       this->collect_nodes_in_all_data(in_rel, true);
1801     }
1802     this->collect_nodes(out_rel, -2, false, false);
1803 }
1804 #endif
1805 
1806 //=============================================================================
1807 Node *LockNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1808 
1809   // perform any generic optimizations first (returns 'this' or NULL)
1810   Node *result = SafePointNode::Ideal(phase, can_reshape);
1811   if (result != NULL)  return result;
1812   // Don't bother trying to transform a dead node
1813   if (in(0) && in(0)->is_top())  return NULL;
1814 
1815   // Now see if we can optimize away this lock.  We don't actually
1816   // remove the locking here, we simply set the _eliminate flag which
1817   // prevents macro expansion from expanding the lock.  Since we don't
1818   // modify the graph, the value returned from this function is the
1819   // one computed above.
1820   if (can_reshape && EliminateLocks && !is_non_esc_obj()) {
1821     //
1822     // If we are locking an unescaped object, the lock/unlock is unnecessary
1823     //
1824     ConnectionGraph *cgr = phase->C->congraph();
1825     if (cgr != NULL && cgr->not_global_escape(obj_node())) {
1826       assert(!is_eliminated() || is_coarsened(), "sanity");
1827       // The lock could be marked eliminated by lock coarsening
1828       // code during first IGVN before EA. Replace coarsened flag
1829       // to eliminate all associated locks/unlocks.
1830 #ifdef ASSERT
1831       this->log_lock_optimization(phase->C,"eliminate_lock_set_non_esc1");
1832 #endif
1833       this->set_non_esc_obj();
1834       return result;
1835     }
1836 
1837     //
1838     // Try lock coarsening
1839     //
1840     PhaseIterGVN* iter = phase->is_IterGVN();
1841     if (iter != NULL && !is_eliminated()) {
1842 
1843       GrowableArray<AbstractLockNode*>   lock_ops;
1844 
1845       Node *ctrl = next_control(in(0));
1846 
1847       // now search back for a matching Unlock
1848       if (find_matching_unlock(ctrl, this, lock_ops)) {
1849         // found an unlock directly preceding this lock.  This is the
1850         // case of single unlock directly control dependent on a
1851         // single lock which is the trivial version of case 1 or 2.
1852       } else if (ctrl->is_Region() ) {
1853         if (find_unlocks_for_region(ctrl->as_Region(), this, lock_ops)) {
1854         // found lock preceded by multiple unlocks along all paths
1855         // joining at this point which is case 3 in description above.
1856         }
1857       } else {
1858         // see if this lock comes from either half of an if and the
1859         // predecessors merges unlocks and the other half of the if
1860         // performs a lock.
1861         if (find_lock_and_unlock_through_if(ctrl, this, lock_ops)) {
1862           // found unlock splitting to an if with locks on both branches.
1863         }
1864       }
1865 
1866       if (lock_ops.length() > 0) {
1867         // add ourselves to the list of locks to be eliminated.
1868         lock_ops.append(this);
1869 
1870   #ifndef PRODUCT
1871         if (PrintEliminateLocks) {
1872           int locks = 0;
1873           int unlocks = 0;
1874           for (int i = 0; i < lock_ops.length(); i++) {
1875             AbstractLockNode* lock = lock_ops.at(i);
1876             if (lock->Opcode() == Op_Lock)
1877               locks++;
1878             else
1879               unlocks++;
1880             if (Verbose) {
1881               lock->dump(1);
1882             }
1883           }
1884           tty->print_cr("***Eliminated %d unlocks and %d locks", unlocks, locks);
1885         }
1886   #endif
1887 
1888         // for each of the identified locks, mark them
1889         // as eliminatable
1890         for (int i = 0; i < lock_ops.length(); i++) {
1891           AbstractLockNode* lock = lock_ops.at(i);
1892 
1893           // Mark it eliminated by coarsening and update any counters
1894 #ifdef ASSERT
1895           lock->log_lock_optimization(phase->C, "eliminate_lock_set_coarsened");
1896 #endif
1897           lock->set_coarsened();
1898         }
1899       } else if (ctrl->is_Region() &&
1900                  iter->_worklist.member(ctrl)) {
1901         // We weren't able to find any opportunities but the region this
1902         // lock is control dependent on hasn't been processed yet so put
1903         // this lock back on the worklist so we can check again once any
1904         // region simplification has occurred.
1905         iter->_worklist.push(this);
1906       }
1907     }
1908   }
1909 
1910   return result;
1911 }
1912 
1913 //=============================================================================
1914 bool LockNode::is_nested_lock_region() {
1915   return is_nested_lock_region(NULL);
1916 }
1917 
1918 // p is used for access to compilation log; no logging if NULL
1919 bool LockNode::is_nested_lock_region(Compile * c) {
1920   BoxLockNode* box = box_node()->as_BoxLock();
1921   int stk_slot = box->stack_slot();
1922   if (stk_slot <= 0) {
1923 #ifdef ASSERT
1924     this->log_lock_optimization(c, "eliminate_lock_INLR_1");
1925 #endif
1926     return false; // External lock or it is not Box (Phi node).
1927   }
1928 
1929   // Ignore complex cases: merged locks or multiple locks.
1930   Node* obj = obj_node();
1931   LockNode* unique_lock = NULL;
1932   if (!box->is_simple_lock_region(&unique_lock, obj)) {
1933 #ifdef ASSERT
1934     this->log_lock_optimization(c, "eliminate_lock_INLR_2a");
1935 #endif
1936     return false;
1937   }
1938   if (unique_lock != this) {
1939 #ifdef ASSERT
1940     this->log_lock_optimization(c, "eliminate_lock_INLR_2b");
1941 #endif
1942     return false;
1943   }
1944 
1945   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1946   obj = bs->step_over_gc_barrier(obj);
1947   // Look for external lock for the same object.
1948   SafePointNode* sfn = this->as_SafePoint();
1949   JVMState* youngest_jvms = sfn->jvms();
1950   int max_depth = youngest_jvms->depth();
1951   for (int depth = 1; depth <= max_depth; depth++) {
1952     JVMState* jvms = youngest_jvms->of_depth(depth);
1953     int num_mon  = jvms->nof_monitors();
1954     // Loop over monitors
1955     for (int idx = 0; idx < num_mon; idx++) {
1956       Node* obj_node = sfn->monitor_obj(jvms, idx);
1957       obj_node = bs->step_over_gc_barrier(obj_node);
1958       BoxLockNode* box_node = sfn->monitor_box(jvms, idx)->as_BoxLock();
1959       if ((box_node->stack_slot() < stk_slot) && obj_node->eqv_uncast(obj)) {
1960         return true;
1961       }
1962     }
1963   }
1964 #ifdef ASSERT
1965   this->log_lock_optimization(c, "eliminate_lock_INLR_3");
1966 #endif
1967   return false;
1968 }
1969 
1970 //=============================================================================
1971 uint UnlockNode::size_of() const { return sizeof(*this); }
1972 
1973 //=============================================================================
1974 Node *UnlockNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1975 
1976   // perform any generic optimizations first (returns 'this' or NULL)
1977   Node *result = SafePointNode::Ideal(phase, can_reshape);
1978   if (result != NULL)  return result;
1979   // Don't bother trying to transform a dead node
1980   if (in(0) && in(0)->is_top())  return NULL;
1981 
1982   // Now see if we can optimize away this unlock.  We don't actually
1983   // remove the unlocking here, we simply set the _eliminate flag which
1984   // prevents macro expansion from expanding the unlock.  Since we don't
1985   // modify the graph, the value returned from this function is the
1986   // one computed above.
1987   // Escape state is defined after Parse phase.
1988   if (can_reshape && EliminateLocks && !is_non_esc_obj()) {
1989     //
1990     // If we are unlocking an unescaped object, the lock/unlock is unnecessary.
1991     //
1992     ConnectionGraph *cgr = phase->C->congraph();
1993     if (cgr != NULL && cgr->not_global_escape(obj_node())) {
1994       assert(!is_eliminated() || is_coarsened(), "sanity");
1995       // The lock could be marked eliminated by lock coarsening
1996       // code during first IGVN before EA. Replace coarsened flag
1997       // to eliminate all associated locks/unlocks.
1998 #ifdef ASSERT
1999       this->log_lock_optimization(phase->C, "eliminate_lock_set_non_esc2");
2000 #endif
2001       this->set_non_esc_obj();
2002     }
2003   }
2004   return result;
2005 }
2006 
2007 const char * AbstractLockNode::kind_as_string() const {
2008   return is_coarsened()   ? "coarsened" :
2009          is_nested()      ? "nested" :
2010          is_non_esc_obj() ? "non_escaping" :
2011          "?";
2012 }
2013 
2014 void AbstractLockNode::log_lock_optimization(Compile *C, const char * tag)  const {
2015   if (C == NULL) {
2016     return;
2017   }
2018   CompileLog* log = C->log();
2019   if (log != NULL) {
2020     log->begin_head("%s lock='%d' compile_id='%d' class_id='%s' kind='%s'",
2021           tag, is_Lock(), C->compile_id(),
2022           is_Unlock() ? "unlock" : is_Lock() ? "lock" : "?",
2023           kind_as_string());
2024     log->stamp();
2025     log->end_head();
2026     JVMState* p = is_Unlock() ? (as_Unlock()->dbg_jvms()) : jvms();
2027     while (p != NULL) {
2028       log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method()));
2029       p = p->caller();
2030     }
2031     log->tail(tag);
2032   }
2033 }
2034 
2035 bool CallNode::may_modify_arraycopy_helper(const TypeOopPtr* dest_t, const TypeOopPtr *t_oop, PhaseTransform *phase) {
2036   if (dest_t->is_known_instance() && t_oop->is_known_instance()) {
2037     return dest_t->instance_id() == t_oop->instance_id();
2038   }
2039 
2040   if (dest_t->isa_instptr() && !dest_t->klass()->equals(phase->C->env()->Object_klass())) {
2041     // clone
2042     if (t_oop->isa_aryptr()) {
2043       return false;
2044     }
2045     if (!t_oop->isa_instptr()) {
2046       return true;
2047     }
2048     if (dest_t->klass()->is_subtype_of(t_oop->klass()) || t_oop->klass()->is_subtype_of(dest_t->klass())) {
2049       return true;
2050     }
2051     // unrelated
2052     return false;
2053   }
2054 
2055   if (dest_t->isa_aryptr()) {
2056     // arraycopy or array clone
2057     if (t_oop->isa_instptr()) {
2058       return false;
2059     }
2060     if (!t_oop->isa_aryptr()) {
2061       return true;
2062     }
2063 
2064     const Type* elem = dest_t->is_aryptr()->elem();
2065     if (elem == Type::BOTTOM) {
2066       // An array but we don't know what elements are
2067       return true;
2068     }
2069 
2070     dest_t = dest_t->add_offset(Type::OffsetBot)->is_oopptr();
2071     uint dest_alias = phase->C->get_alias_index(dest_t);
2072     uint t_oop_alias = phase->C->get_alias_index(t_oop);
2073 
2074     return dest_alias == t_oop_alias;
2075   }
2076 
2077   return true;
2078 }
2079