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 "interpreter/interpreter.hpp"
  30 #include "opto/callGenerator.hpp"
  31 #include "opto/callnode.hpp"
  32 #include "opto/castnode.hpp"
  33 #include "opto/convertnode.hpp"
  34 #include "opto/escape.hpp"
  35 #include "opto/locknode.hpp"
  36 #include "opto/machnode.hpp"
  37 #include "opto/matcher.hpp"
  38 #include "opto/parse.hpp"
  39 #include "opto/regalloc.hpp"
  40 #include "opto/regmask.hpp"
  41 #include "opto/rootnode.hpp"
  42 #include "opto/runtime.hpp"
  43 #include "opto/valuetypenode.hpp"
  44 #include "runtime/sharedRuntime.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, const RegMask* mask) {
  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       } else if (cik->is_value_array_klass()) {
 483         ciKlass* cie = cik->as_value_array_klass()->base_element_klass();
 484         cie->print_name_on(st);
 485         st->print("[%d]", spobj->n_fields());
 486         int ndim = cik->as_array_klass()->dimension() - 1;
 487         while (ndim-- > 0) {
 488           st->print("[]");
 489         }
 490       }
 491       st->print("={");
 492       uint nf = spobj->n_fields();
 493       if (nf > 0) {
 494         uint first_ind = spobj->first_index(mcall->jvms());
 495         Node* fld_node = mcall->in(first_ind);
 496         ciField* cifield;
 497         if (iklass != NULL) {
 498           st->print(" [");
 499           cifield = iklass->nonstatic_field_at(0);
 500           cifield->print_name_on(st);
 501           format_helper(regalloc, st, fld_node, ":", 0, &scobjs);
 502         } else {
 503           format_helper(regalloc, st, fld_node, "[", 0, &scobjs);
 504         }
 505         for (uint j = 1; j < nf; j++) {
 506           fld_node = mcall->in(first_ind+j);
 507           if (iklass != NULL) {
 508             st->print(", [");
 509             cifield = iklass->nonstatic_field_at(j);
 510             cifield->print_name_on(st);
 511             format_helper(regalloc, st, fld_node, ":", j, &scobjs);
 512           } else {
 513             format_helper(regalloc, st, fld_node, ", [", j, &scobjs);
 514           }
 515         }
 516       }
 517       st->print(" }");
 518     }
 519   }
 520   st->cr();
 521   if (caller() != NULL) caller()->format(regalloc, n, st);
 522 }
 523 
 524 
 525 void JVMState::dump_spec(outputStream *st) const {
 526   if (_method != NULL) {
 527     bool printed = false;
 528     if (!Verbose) {
 529       // The JVMS dumps make really, really long lines.
 530       // Take out the most boring parts, which are the package prefixes.
 531       char buf[500];
 532       stringStream namest(buf, sizeof(buf));
 533       _method->print_short_name(&namest);
 534       if (namest.count() < sizeof(buf)) {
 535         const char* name = namest.base();
 536         if (name[0] == ' ')  ++name;
 537         const char* endcn = strchr(name, ':');  // end of class name
 538         if (endcn == NULL)  endcn = strchr(name, '(');
 539         if (endcn == NULL)  endcn = name + strlen(name);
 540         while (endcn > name && endcn[-1] != '.' && endcn[-1] != '/')
 541           --endcn;
 542         st->print(" %s", endcn);
 543         printed = true;
 544       }
 545     }
 546     if (!printed)
 547       _method->print_short_name(st);
 548     st->print(" @ bci:%d",_bci);
 549     if(_reexecute == Reexecute_True)
 550       st->print(" reexecute");
 551   } else {
 552     st->print(" runtime stub");
 553   }
 554   if (caller() != NULL)  caller()->dump_spec(st);
 555 }
 556 
 557 
 558 void JVMState::dump_on(outputStream* st) const {
 559   bool print_map = _map && !((uintptr_t)_map & 1) &&
 560                   ((caller() == NULL) || (caller()->map() != _map));
 561   if (print_map) {
 562     if (_map->len() > _map->req()) {  // _map->has_exceptions()
 563       Node* ex = _map->in(_map->req());  // _map->next_exception()
 564       // skip the first one; it's already being printed
 565       while (ex != NULL && ex->len() > ex->req()) {
 566         ex = ex->in(ex->req());  // ex->next_exception()
 567         ex->dump(1);
 568       }
 569     }
 570     _map->dump(Verbose ? 2 : 1);
 571   }
 572   if (caller() != NULL) {
 573     caller()->dump_on(st);
 574   }
 575   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=",
 576              depth(), locoff(), stkoff(), argoff(), monoff(), scloff(), endoff(), monitor_depth(), sp(), bci(), should_reexecute()?"true":"false");
 577   if (_method == NULL) {
 578     st->print_cr("(none)");
 579   } else {
 580     _method->print_name(st);
 581     st->cr();
 582     if (bci() >= 0 && bci() < _method->code_size()) {
 583       st->print("    bc: ");
 584       _method->print_codes_on(bci(), bci()+1, st);
 585     }
 586   }
 587 }
 588 
 589 // Extra way to dump a jvms from the debugger,
 590 // to avoid a bug with C++ member function calls.
 591 void dump_jvms(JVMState* jvms) {
 592   jvms->dump();
 593 }
 594 #endif
 595 
 596 //--------------------------clone_shallow--------------------------------------
 597 JVMState* JVMState::clone_shallow(Compile* C) const {
 598   JVMState* n = has_method() ? new (C) JVMState(_method, _caller) : new (C) JVMState(0);
 599   n->set_bci(_bci);
 600   n->_reexecute = _reexecute;
 601   n->set_locoff(_locoff);
 602   n->set_stkoff(_stkoff);
 603   n->set_monoff(_monoff);
 604   n->set_scloff(_scloff);
 605   n->set_endoff(_endoff);
 606   n->set_sp(_sp);
 607   n->set_map(_map);
 608   return n;
 609 }
 610 
 611 //---------------------------clone_deep----------------------------------------
 612 JVMState* JVMState::clone_deep(Compile* C) const {
 613   JVMState* n = clone_shallow(C);
 614   for (JVMState* p = n; p->_caller != NULL; p = p->_caller) {
 615     p->_caller = p->_caller->clone_shallow(C);
 616   }
 617   assert(n->depth() == depth(), "sanity");
 618   assert(n->debug_depth() == debug_depth(), "sanity");
 619   return n;
 620 }
 621 
 622 /**
 623  * Reset map for all callers
 624  */
 625 void JVMState::set_map_deep(SafePointNode* map) {
 626   for (JVMState* p = this; p->_caller != NULL; p = p->_caller) {
 627     p->set_map(map);
 628   }
 629 }
 630 
 631 // Adapt offsets in in-array after adding or removing an edge.
 632 // Prerequisite is that the JVMState is used by only one node.
 633 void JVMState::adapt_position(int delta) {
 634   for (JVMState* jvms = this; jvms != NULL; jvms = jvms->caller()) {
 635     jvms->set_locoff(jvms->locoff() + delta);
 636     jvms->set_stkoff(jvms->stkoff() + delta);
 637     jvms->set_monoff(jvms->monoff() + delta);
 638     jvms->set_scloff(jvms->scloff() + delta);
 639     jvms->set_endoff(jvms->endoff() + delta);
 640   }
 641 }
 642 
 643 // Mirror the stack size calculation in the deopt code
 644 // How much stack space would we need at this point in the program in
 645 // case of deoptimization?
 646 int JVMState::interpreter_frame_size() const {
 647   const JVMState* jvms = this;
 648   int size = 0;
 649   int callee_parameters = 0;
 650   int callee_locals = 0;
 651   int extra_args = method()->max_stack() - stk_size();
 652 
 653   while (jvms != NULL) {
 654     int locks = jvms->nof_monitors();
 655     int temps = jvms->stk_size();
 656     bool is_top_frame = (jvms == this);
 657     ciMethod* method = jvms->method();
 658 
 659     int frame_size = BytesPerWord * Interpreter::size_activation(method->max_stack(),
 660                                                                  temps + callee_parameters,
 661                                                                  extra_args,
 662                                                                  locks,
 663                                                                  callee_parameters,
 664                                                                  callee_locals,
 665                                                                  is_top_frame);
 666     size += frame_size;
 667 
 668     callee_parameters = method->size_of_parameters();
 669     callee_locals = method->max_locals();
 670     extra_args = 0;
 671     jvms = jvms->caller();
 672   }
 673   return size + Deoptimization::last_frame_adjust(0, callee_locals) * BytesPerWord;
 674 }
 675 
 676 //=============================================================================
 677 uint CallNode::cmp( const Node &n ) const
 678 { return _tf == ((CallNode&)n)._tf && _jvms == ((CallNode&)n)._jvms; }
 679 #ifndef PRODUCT
 680 void CallNode::dump_req(outputStream *st) const {
 681   // Dump the required inputs, enclosed in '(' and ')'
 682   uint i;                       // Exit value of loop
 683   for (i = 0; i < req(); i++) {    // For all required inputs
 684     if (i == TypeFunc::Parms) st->print("(");
 685     if (in(i)) st->print("%c%d ", Compile::current()->node_arena()->contains(in(i)) ? ' ' : 'o', in(i)->_idx);
 686     else st->print("_ ");
 687   }
 688   st->print(")");
 689 }
 690 
 691 void CallNode::dump_spec(outputStream *st) const {
 692   st->print(" ");
 693   if (tf() != NULL)  tf()->dump_on(st);
 694   if (_cnt != COUNT_UNKNOWN)  st->print(" C=%f",_cnt);
 695   if (jvms() != NULL)  jvms()->dump_spec(st);
 696 }
 697 #endif
 698 
 699 const Type *CallNode::bottom_type() const { return tf()->range_cc(); }
 700 const Type* CallNode::Value(PhaseGVN* phase) const {
 701   if (!in(0) || phase->type(in(0)) == Type::TOP) {
 702     return Type::TOP;
 703   }
 704   return tf()->range_cc();
 705 }
 706 
 707 //------------------------------calling_convention-----------------------------
 708 void CallNode::calling_convention(BasicType* sig_bt, VMRegPair *parm_regs, uint argcnt) const {
 709   if (_entry_point == StubRoutines::store_value_type_fields_to_buf()) {
 710     // The call to that stub is a special case: its inputs are
 711     // multiple values returned from a call and so it should follow
 712     // the return convention.
 713     SharedRuntime::java_return_convention(sig_bt, parm_regs, argcnt);
 714     return;
 715   }
 716   // Use the standard compiler calling convention
 717   Matcher::calling_convention( sig_bt, parm_regs, argcnt, true );
 718 }
 719 
 720 
 721 //------------------------------match------------------------------------------
 722 // Construct projections for control, I/O, memory-fields, ..., and
 723 // return result(s) along with their RegMask info
 724 Node *CallNode::match(const ProjNode *proj, const Matcher *match, const RegMask* mask) {
 725   uint con = proj->_con;
 726   const TypeTuple *range_cc = tf()->range_cc();
 727   if (con >= TypeFunc::Parms) {
 728     if (is_CallRuntime()) {
 729       if (con == TypeFunc::Parms) {
 730         uint ideal_reg = range_cc->field_at(TypeFunc::Parms)->ideal_reg();
 731         OptoRegPair regs = match->c_return_value(ideal_reg,true);
 732         RegMask rm = RegMask(regs.first());
 733         if (OptoReg::is_valid(regs.second())) {
 734           rm.Insert(regs.second());
 735         }
 736         return new MachProjNode(this,con,rm,ideal_reg);
 737       } else {
 738         assert(con == TypeFunc::Parms+1, "only one return value");
 739         assert(range_cc->field_at(TypeFunc::Parms+1) == Type::HALF, "");
 740         return new MachProjNode(this,con, RegMask::Empty, (uint)OptoReg::Bad);
 741       }
 742     } else {
 743       // The Call may return multiple values (value type fields): we
 744       // create one projection per returned values.
 745       assert(con <= TypeFunc::Parms+1 || ValueTypeReturnedAsFields, "only for multi value return");
 746       uint ideal_reg = range_cc->field_at(con)->ideal_reg();
 747       return new MachProjNode(this, con, mask[con-TypeFunc::Parms], ideal_reg);
 748     }
 749   }
 750 
 751   switch (con) {
 752   case TypeFunc::Control:
 753   case TypeFunc::I_O:
 754   case TypeFunc::Memory:
 755     return new MachProjNode(this,proj->_con,RegMask::Empty,MachProjNode::unmatched_proj);
 756 
 757   case TypeFunc::ReturnAdr:
 758   case TypeFunc::FramePtr:
 759   default:
 760     ShouldNotReachHere();
 761   }
 762   return NULL;
 763 }
 764 
 765 // Do we Match on this edge index or not?  Match no edges
 766 uint CallNode::match_edge(uint idx) const {
 767   return 0;
 768 }
 769 
 770 //
 771 // Determine whether the call could modify the field of the specified
 772 // instance at the specified offset.
 773 //
 774 bool CallNode::may_modify(const TypeOopPtr *t_oop, PhaseTransform *phase) {
 775   assert((t_oop != NULL), "sanity");
 776   if (is_call_to_arraycopystub() && strcmp(_name, "unsafe_arraycopy") != 0) {
 777     const TypeTuple* args = _tf->domain_sig();
 778     Node* dest = NULL;
 779     // Stubs that can be called once an ArrayCopyNode is expanded have
 780     // different signatures. Look for the second pointer argument,
 781     // that is the destination of the copy.
 782     for (uint i = TypeFunc::Parms, j = 0; i < args->cnt(); i++) {
 783       if (args->field_at(i)->isa_ptr()) {
 784         j++;
 785         if (j == 2) {
 786           dest = in(i);
 787           break;
 788         }
 789       }
 790     }
 791     if (!dest->is_top() && may_modify_arraycopy_helper(phase->type(dest)->is_oopptr(), t_oop, phase)) {
 792       return true;
 793     }
 794     return false;
 795   }
 796   if (t_oop->is_known_instance()) {
 797     // The instance_id is set only for scalar-replaceable allocations which
 798     // are not passed as arguments according to Escape Analysis.
 799     return false;
 800   }
 801   if (t_oop->is_ptr_to_boxed_value()) {
 802     ciKlass* boxing_klass = t_oop->klass();
 803     if (is_CallStaticJava() && as_CallStaticJava()->is_boxing_method()) {
 804       // Skip unrelated boxing methods.
 805       Node* proj = proj_out_or_null(TypeFunc::Parms);
 806       if ((proj == NULL) || (phase->type(proj)->is_instptr()->klass() != boxing_klass)) {
 807         return false;
 808       }
 809     }
 810     if (is_CallJava() && as_CallJava()->method() != NULL) {
 811       ciMethod* meth = as_CallJava()->method();
 812       if (meth->is_getter()) {
 813         return false;
 814       }
 815       // May modify (by reflection) if an boxing object is passed
 816       // as argument or returned.
 817       Node* proj = returns_pointer() ? proj_out_or_null(TypeFunc::Parms) : NULL;
 818       if (proj != NULL) {
 819         const TypeInstPtr* inst_t = phase->type(proj)->isa_instptr();
 820         if ((inst_t != NULL) && (!inst_t->klass_is_exact() ||
 821                                  (inst_t->klass() == boxing_klass))) {
 822           return true;
 823         }
 824       }
 825       const TypeTuple* d = tf()->domain_cc();
 826       for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
 827         const TypeInstPtr* inst_t = d->field_at(i)->isa_instptr();
 828         if ((inst_t != NULL) && (!inst_t->klass_is_exact() ||
 829                                  (inst_t->klass() == boxing_klass))) {
 830           return true;
 831         }
 832       }
 833       return false;
 834     }
 835   }
 836   return true;
 837 }
 838 
 839 // Does this call have a direct reference to n other than debug information?
 840 bool CallNode::has_non_debug_use(Node *n) {
 841   const TypeTuple * d = tf()->domain_cc();
 842   for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
 843     Node *arg = in(i);
 844     if (arg == n) {
 845       return true;
 846     }
 847   }
 848   return false;
 849 }
 850 
 851 bool CallNode::has_debug_use(Node *n) {
 852   assert(jvms() != NULL, "jvms should not be null");
 853   for (uint i = jvms()->debug_start(); i < jvms()->debug_end(); i++) {
 854     Node *arg = in(i);
 855     if (arg == n) {
 856       return true;
 857     }
 858   }
 859   return false;
 860 }
 861 
 862 // Returns the unique CheckCastPP of a call
 863 // or 'this' if there are several CheckCastPP or unexpected uses
 864 // or returns NULL if there is no one.
 865 Node *CallNode::result_cast() {
 866   Node *cast = NULL;
 867 
 868   Node *p = proj_out_or_null(TypeFunc::Parms);
 869   if (p == NULL)
 870     return NULL;
 871 
 872   for (DUIterator_Fast imax, i = p->fast_outs(imax); i < imax; i++) {
 873     Node *use = p->fast_out(i);
 874     if (use->is_CheckCastPP()) {
 875       if (cast != NULL) {
 876         return this;  // more than 1 CheckCastPP
 877       }
 878       cast = use;
 879     } else if (!use->is_Initialize() &&
 880                !use->is_AddP() &&
 881                use->Opcode() != Op_MemBarStoreStore) {
 882       // Expected uses are restricted to a CheckCastPP, an Initialize
 883       // node, a MemBarStoreStore (clone) and AddP nodes. If we
 884       // encounter any other use (a Phi node can be seen in rare
 885       // cases) return this to prevent incorrect optimizations.
 886       return this;
 887     }
 888   }
 889   return cast;
 890 }
 891 
 892 
 893 CallProjections* CallNode::extract_projections(bool separate_io_proj, bool do_asserts) {
 894   uint max_res = TypeFunc::Parms-1;
 895   for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
 896     ProjNode *pn = fast_out(i)->as_Proj();
 897     max_res = MAX2(max_res, pn->_con);
 898   }
 899 
 900   assert(max_res < _tf->range_cc()->cnt(), "result out of bounds");
 901 
 902   uint projs_size = sizeof(CallProjections);
 903   if (max_res > TypeFunc::Parms) {
 904     projs_size += (max_res-TypeFunc::Parms)*sizeof(Node*);
 905   }
 906   char* projs_storage = resource_allocate_bytes(projs_size);
 907   CallProjections* projs = new(projs_storage)CallProjections(max_res - TypeFunc::Parms + 1);
 908 
 909   for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
 910     ProjNode *pn = fast_out(i)->as_Proj();
 911     if (pn->outcnt() == 0) continue;
 912     switch (pn->_con) {
 913     case TypeFunc::Control:
 914       {
 915         // For Control (fallthrough) and I_O (catch_all_index) we have CatchProj -> Catch -> Proj
 916         projs->fallthrough_proj = pn;
 917         DUIterator_Fast jmax, j = pn->fast_outs(jmax);
 918         const Node *cn = pn->fast_out(j);
 919         if (cn->is_Catch()) {
 920           ProjNode *cpn = NULL;
 921           for (DUIterator_Fast kmax, k = cn->fast_outs(kmax); k < kmax; k++) {
 922             cpn = cn->fast_out(k)->as_Proj();
 923             assert(cpn->is_CatchProj(), "must be a CatchProjNode");
 924             if (cpn->_con == CatchProjNode::fall_through_index)
 925               projs->fallthrough_catchproj = cpn;
 926             else {
 927               assert(cpn->_con == CatchProjNode::catch_all_index, "must be correct index.");
 928               projs->catchall_catchproj = cpn;
 929             }
 930           }
 931         }
 932         break;
 933       }
 934     case TypeFunc::I_O:
 935       if (pn->_is_io_use)
 936         projs->catchall_ioproj = pn;
 937       else
 938         projs->fallthrough_ioproj = pn;
 939       for (DUIterator j = pn->outs(); pn->has_out(j); j++) {
 940         Node* e = pn->out(j);
 941         if (e->Opcode() == Op_CreateEx && e->in(0)->is_CatchProj() && e->outcnt() > 0) {
 942           assert(projs->exobj == NULL, "only one");
 943           projs->exobj = e;
 944         }
 945       }
 946       break;
 947     case TypeFunc::Memory:
 948       if (pn->_is_io_use)
 949         projs->catchall_memproj = pn;
 950       else
 951         projs->fallthrough_memproj = pn;
 952       break;
 953     case TypeFunc::Parms:
 954       projs->resproj[0] = pn;
 955       break;
 956     default:
 957       assert(pn->_con <= max_res, "unexpected projection from allocation node.");
 958       projs->resproj[pn->_con-TypeFunc::Parms] = pn;
 959       break;
 960     }
 961   }
 962 
 963   // The resproj may not exist because the result could be ignored
 964   // and the exception object may not exist if an exception handler
 965   // swallows the exception but all the other must exist and be found.
 966   assert(projs->fallthrough_proj      != NULL, "must be found");
 967   do_asserts = do_asserts && !Compile::current()->inlining_incrementally();
 968   assert(!do_asserts || projs->fallthrough_catchproj != NULL, "must be found");
 969   assert(!do_asserts || projs->fallthrough_memproj   != NULL, "must be found");
 970   assert(!do_asserts || projs->fallthrough_ioproj    != NULL, "must be found");
 971   assert(!do_asserts || projs->catchall_catchproj    != NULL, "must be found");
 972   if (separate_io_proj) {
 973     assert(!do_asserts || projs->catchall_memproj    != NULL, "must be found");
 974     assert(!do_asserts || projs->catchall_ioproj     != NULL, "must be found");
 975   }
 976   return projs;
 977 }
 978 
 979 Node *CallNode::Ideal(PhaseGVN *phase, bool can_reshape) {
 980   CallGenerator* cg = generator();
 981   if (can_reshape && cg != NULL && cg->is_mh_late_inline() && !cg->already_attempted()) {
 982     // Check whether this MH handle call becomes a candidate for inlining
 983     ciMethod* callee = cg->method();
 984     vmIntrinsics::ID iid = callee->intrinsic_id();
 985     if (iid == vmIntrinsics::_invokeBasic) {
 986       if (in(TypeFunc::Parms)->Opcode() == Op_ConP) {
 987         phase->C->prepend_late_inline(cg);
 988         set_generator(NULL);
 989       }
 990     } else {
 991       assert(callee->has_member_arg(), "wrong type of call?");
 992       if (in(TypeFunc::Parms + callee->arg_size() - 1)->Opcode() == Op_ConP) {
 993         phase->C->prepend_late_inline(cg);
 994         set_generator(NULL);
 995       }
 996     }
 997   }
 998   return SafePointNode::Ideal(phase, can_reshape);
 999 }
1000 
1001 bool CallNode::is_call_to_arraycopystub() const {
1002   if (_name != NULL && strstr(_name, "arraycopy") != 0) {
1003     return true;
1004   }
1005   return false;
1006 }
1007 
1008 //=============================================================================
1009 uint CallJavaNode::size_of() const { return sizeof(*this); }
1010 uint CallJavaNode::cmp( const Node &n ) const {
1011   CallJavaNode &call = (CallJavaNode&)n;
1012   return CallNode::cmp(call) && _method == call._method &&
1013          _override_symbolic_info == call._override_symbolic_info;
1014 }
1015 #ifndef PRODUCT
1016 void CallJavaNode::dump_spec(outputStream *st) const {
1017   if( _method ) _method->print_short_name(st);
1018   CallNode::dump_spec(st);
1019 }
1020 
1021 void CallJavaNode::dump_compact_spec(outputStream* st) const {
1022   if (_method) {
1023     _method->print_short_name(st);
1024   } else {
1025     st->print("<?>");
1026   }
1027 }
1028 #endif
1029 
1030 //=============================================================================
1031 uint CallStaticJavaNode::size_of() const { return sizeof(*this); }
1032 uint CallStaticJavaNode::cmp( const Node &n ) const {
1033   CallStaticJavaNode &call = (CallStaticJavaNode&)n;
1034   return CallJavaNode::cmp(call);
1035 }
1036 
1037 //----------------------------uncommon_trap_request----------------------------
1038 // If this is an uncommon trap, return the request code, else zero.
1039 int CallStaticJavaNode::uncommon_trap_request() const {
1040   if (_name != NULL && !strcmp(_name, "uncommon_trap")) {
1041     return extract_uncommon_trap_request(this);
1042   }
1043   return 0;
1044 }
1045 int CallStaticJavaNode::extract_uncommon_trap_request(const Node* call) {
1046 #ifndef PRODUCT
1047   if (!(call->req() > TypeFunc::Parms &&
1048         call->in(TypeFunc::Parms) != NULL &&
1049         call->in(TypeFunc::Parms)->is_Con() &&
1050         call->in(TypeFunc::Parms)->bottom_type()->isa_int())) {
1051     assert(in_dump() != 0, "OK if dumping");
1052     tty->print("[bad uncommon trap]");
1053     return 0;
1054   }
1055 #endif
1056   return call->in(TypeFunc::Parms)->bottom_type()->is_int()->get_con();
1057 }
1058 
1059 #ifndef PRODUCT
1060 void CallStaticJavaNode::dump_spec(outputStream *st) const {
1061   st->print("# Static ");
1062   if (_name != NULL) {
1063     st->print("%s", _name);
1064     int trap_req = uncommon_trap_request();
1065     if (trap_req != 0) {
1066       char buf[100];
1067       st->print("(%s)",
1068                  Deoptimization::format_trap_request(buf, sizeof(buf),
1069                                                      trap_req));
1070     }
1071     st->print(" ");
1072   }
1073   CallJavaNode::dump_spec(st);
1074 }
1075 
1076 void CallStaticJavaNode::dump_compact_spec(outputStream* st) const {
1077   if (_method) {
1078     _method->print_short_name(st);
1079   } else if (_name) {
1080     st->print("%s", _name);
1081   } else {
1082     st->print("<?>");
1083   }
1084 }
1085 #endif
1086 
1087 //=============================================================================
1088 uint CallDynamicJavaNode::size_of() const { return sizeof(*this); }
1089 uint CallDynamicJavaNode::cmp( const Node &n ) const {
1090   CallDynamicJavaNode &call = (CallDynamicJavaNode&)n;
1091   return CallJavaNode::cmp(call);
1092 }
1093 #ifndef PRODUCT
1094 void CallDynamicJavaNode::dump_spec(outputStream *st) const {
1095   st->print("# Dynamic ");
1096   CallJavaNode::dump_spec(st);
1097 }
1098 #endif
1099 
1100 //=============================================================================
1101 uint CallRuntimeNode::size_of() const { return sizeof(*this); }
1102 uint CallRuntimeNode::cmp( const Node &n ) const {
1103   CallRuntimeNode &call = (CallRuntimeNode&)n;
1104   return CallNode::cmp(call) && !strcmp(_name,call._name);
1105 }
1106 #ifndef PRODUCT
1107 void CallRuntimeNode::dump_spec(outputStream *st) const {
1108   st->print("# ");
1109   st->print("%s", _name);
1110   CallNode::dump_spec(st);
1111 }
1112 #endif
1113 
1114 //------------------------------calling_convention-----------------------------
1115 void CallRuntimeNode::calling_convention( BasicType* sig_bt, VMRegPair *parm_regs, uint argcnt ) const {
1116   if (_entry_point == NULL) {
1117     // The call to that stub is a special case: its inputs are
1118     // multiple values returned from a call and so it should follow
1119     // the return convention.
1120     SharedRuntime::java_return_convention(sig_bt, parm_regs, argcnt);
1121     return;
1122   }
1123   Matcher::c_calling_convention( sig_bt, parm_regs, argcnt );
1124 }
1125 
1126 //=============================================================================
1127 //------------------------------calling_convention-----------------------------
1128 
1129 
1130 //=============================================================================
1131 #ifndef PRODUCT
1132 void CallLeafNode::dump_spec(outputStream *st) const {
1133   st->print("# ");
1134   st->print("%s", _name);
1135   CallNode::dump_spec(st);
1136 }
1137 #endif
1138 
1139 uint CallLeafNoFPNode::match_edge(uint idx) const {
1140   // Null entry point is a special case for which the target is in a
1141   // register. Need to match that edge.
1142   return entry_point() == NULL && idx == TypeFunc::Parms;
1143 }
1144 
1145 //=============================================================================
1146 
1147 void SafePointNode::set_local(JVMState* jvms, uint idx, Node *c) {
1148   assert(verify_jvms(jvms), "jvms must match");
1149   int loc = jvms->locoff() + idx;
1150   if (in(loc)->is_top() && idx > 0 && !c->is_top() ) {
1151     // If current local idx is top then local idx - 1 could
1152     // be a long/double that needs to be killed since top could
1153     // represent the 2nd half ofthe long/double.
1154     uint ideal = in(loc -1)->ideal_reg();
1155     if (ideal == Op_RegD || ideal == Op_RegL) {
1156       // set other (low index) half to top
1157       set_req(loc - 1, in(loc));
1158     }
1159   }
1160   set_req(loc, c);
1161 }
1162 
1163 uint SafePointNode::size_of() const { return sizeof(*this); }
1164 uint SafePointNode::cmp( const Node &n ) const {
1165   return (&n == this);          // Always fail except on self
1166 }
1167 
1168 //-------------------------set_next_exception----------------------------------
1169 void SafePointNode::set_next_exception(SafePointNode* n) {
1170   assert(n == NULL || n->Opcode() == Op_SafePoint, "correct value for next_exception");
1171   if (len() == req()) {
1172     if (n != NULL)  add_prec(n);
1173   } else {
1174     set_prec(req(), n);
1175   }
1176 }
1177 
1178 
1179 //----------------------------next_exception-----------------------------------
1180 SafePointNode* SafePointNode::next_exception() const {
1181   if (len() == req()) {
1182     return NULL;
1183   } else {
1184     Node* n = in(req());
1185     assert(n == NULL || n->Opcode() == Op_SafePoint, "no other uses of prec edges");
1186     return (SafePointNode*) n;
1187   }
1188 }
1189 
1190 
1191 //------------------------------Ideal------------------------------------------
1192 // Skip over any collapsed Regions
1193 Node *SafePointNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1194   if (remove_dead_region(phase, can_reshape)) {
1195     return this;
1196   }
1197   if (jvms() != NULL) {
1198     bool progress = false;
1199     // A ValueTypeNode that was already heap allocated in the debug
1200     // info?  Reference the object directly. Helps removal of useless
1201     // value type allocations with incremental inlining.
1202     for (uint i = jvms()->debug_start(); i < jvms()->debug_end(); i++) {
1203       Node *arg = in(i);
1204       if (arg->is_ValueType()) {
1205         ValueTypeNode* vt = arg->as_ValueType();
1206         Node* in_oop = vt->get_oop();
1207         const Type* oop_type = phase->type(in_oop);
1208         if (!TypePtr::NULL_PTR->higher_equal(oop_type)) {
1209           set_req(i, in_oop);
1210           progress = true;
1211         }
1212       }
1213     }
1214     if (progress) {
1215       return this;
1216     }
1217   }
1218   return NULL;
1219 }
1220 
1221 //------------------------------Identity---------------------------------------
1222 // Remove obviously duplicate safepoints
1223 Node* SafePointNode::Identity(PhaseGVN* phase) {
1224 
1225   // If you have back to back safepoints, remove one
1226   if( in(TypeFunc::Control)->is_SafePoint() )
1227     return in(TypeFunc::Control);
1228 
1229   if( in(0)->is_Proj() ) {
1230     Node *n0 = in(0)->in(0);
1231     // Check if he is a call projection (except Leaf Call)
1232     if( n0->is_Catch() ) {
1233       n0 = n0->in(0)->in(0);
1234       assert( n0->is_Call(), "expect a call here" );
1235     }
1236     if( n0->is_Call() && n0->as_Call()->guaranteed_safepoint() ) {
1237       // Useless Safepoint, so remove it
1238       return in(TypeFunc::Control);
1239     }
1240   }
1241 
1242   return this;
1243 }
1244 
1245 //------------------------------Value------------------------------------------
1246 const Type* SafePointNode::Value(PhaseGVN* phase) const {
1247   if( phase->type(in(0)) == Type::TOP ) return Type::TOP;
1248   if( phase->eqv( in(0), this ) ) return Type::TOP; // Dead infinite loop
1249   return Type::CONTROL;
1250 }
1251 
1252 #ifndef PRODUCT
1253 void SafePointNode::dump_spec(outputStream *st) const {
1254   st->print(" SafePoint ");
1255   _replaced_nodes.dump(st);
1256 }
1257 
1258 // The related nodes of a SafepointNode are all data inputs, excluding the
1259 // control boundary, as well as all outputs till level 2 (to include projection
1260 // nodes and targets). In compact mode, just include inputs till level 1 and
1261 // outputs as before.
1262 void SafePointNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
1263   if (compact) {
1264     this->collect_nodes(in_rel, 1, false, false);
1265   } else {
1266     this->collect_nodes_in_all_data(in_rel, false);
1267   }
1268   this->collect_nodes(out_rel, -2, false, false);
1269 }
1270 #endif
1271 
1272 const RegMask &SafePointNode::in_RegMask(uint idx) const {
1273   if( idx < TypeFunc::Parms ) return RegMask::Empty;
1274   // Values outside the domain represent debug info
1275   return *(Compile::current()->matcher()->idealreg2debugmask[in(idx)->ideal_reg()]);
1276 }
1277 const RegMask &SafePointNode::out_RegMask() const {
1278   return RegMask::Empty;
1279 }
1280 
1281 
1282 void SafePointNode::grow_stack(JVMState* jvms, uint grow_by) {
1283   assert((int)grow_by > 0, "sanity");
1284   int monoff = jvms->monoff();
1285   int scloff = jvms->scloff();
1286   int endoff = jvms->endoff();
1287   assert(endoff == (int)req(), "no other states or debug info after me");
1288   Node* top = Compile::current()->top();
1289   for (uint i = 0; i < grow_by; i++) {
1290     ins_req(monoff, top);
1291   }
1292   jvms->set_monoff(monoff + grow_by);
1293   jvms->set_scloff(scloff + grow_by);
1294   jvms->set_endoff(endoff + grow_by);
1295 }
1296 
1297 void SafePointNode::push_monitor(const FastLockNode *lock) {
1298   // Add a LockNode, which points to both the original BoxLockNode (the
1299   // stack space for the monitor) and the Object being locked.
1300   const int MonitorEdges = 2;
1301   assert(JVMState::logMonitorEdges == exact_log2(MonitorEdges), "correct MonitorEdges");
1302   assert(req() == jvms()->endoff(), "correct sizing");
1303   int nextmon = jvms()->scloff();
1304   if (GenerateSynchronizationCode) {
1305     ins_req(nextmon,   lock->box_node());
1306     ins_req(nextmon+1, lock->obj_node());
1307   } else {
1308     Node* top = Compile::current()->top();
1309     ins_req(nextmon, top);
1310     ins_req(nextmon, top);
1311   }
1312   jvms()->set_scloff(nextmon + MonitorEdges);
1313   jvms()->set_endoff(req());
1314 }
1315 
1316 void SafePointNode::pop_monitor() {
1317   // Delete last monitor from debug info
1318   debug_only(int num_before_pop = jvms()->nof_monitors());
1319   const int MonitorEdges = 2;
1320   assert(JVMState::logMonitorEdges == exact_log2(MonitorEdges), "correct MonitorEdges");
1321   int scloff = jvms()->scloff();
1322   int endoff = jvms()->endoff();
1323   int new_scloff = scloff - MonitorEdges;
1324   int new_endoff = endoff - MonitorEdges;
1325   jvms()->set_scloff(new_scloff);
1326   jvms()->set_endoff(new_endoff);
1327   while (scloff > new_scloff)  del_req_ordered(--scloff);
1328   assert(jvms()->nof_monitors() == num_before_pop-1, "");
1329 }
1330 
1331 Node *SafePointNode::peek_monitor_box() const {
1332   int mon = jvms()->nof_monitors() - 1;
1333   assert(mon >= 0, "must have a monitor");
1334   return monitor_box(jvms(), mon);
1335 }
1336 
1337 Node *SafePointNode::peek_monitor_obj() const {
1338   int mon = jvms()->nof_monitors() - 1;
1339   assert(mon >= 0, "must have a monitor");
1340   return monitor_obj(jvms(), mon);
1341 }
1342 
1343 // Do we Match on this edge index or not?  Match no edges
1344 uint SafePointNode::match_edge(uint idx) const {
1345   if( !needs_polling_address_input() )
1346     return 0;
1347 
1348   return (TypeFunc::Parms == idx);
1349 }
1350 
1351 //==============  SafePointScalarObjectNode  ==============
1352 
1353 SafePointScalarObjectNode::SafePointScalarObjectNode(const TypeOopPtr* tp,
1354 #ifdef ASSERT
1355                                                      AllocateNode* alloc,
1356 #endif
1357                                                      uint first_index,
1358                                                      uint n_fields) :
1359   TypeNode(tp, 1), // 1 control input -- seems required.  Get from root.
1360 #ifdef ASSERT
1361   _alloc(alloc),
1362 #endif
1363   _first_index(first_index),
1364   _n_fields(n_fields)
1365 {
1366   init_class_id(Class_SafePointScalarObject);
1367 }
1368 
1369 // Do not allow value-numbering for SafePointScalarObject node.
1370 uint SafePointScalarObjectNode::hash() const { return NO_HASH; }
1371 uint SafePointScalarObjectNode::cmp( const Node &n ) const {
1372   return (&n == this); // Always fail except on self
1373 }
1374 
1375 uint SafePointScalarObjectNode::ideal_reg() const {
1376   return 0; // No matching to machine instruction
1377 }
1378 
1379 const RegMask &SafePointScalarObjectNode::in_RegMask(uint idx) const {
1380   return *(Compile::current()->matcher()->idealreg2debugmask[in(idx)->ideal_reg()]);
1381 }
1382 
1383 const RegMask &SafePointScalarObjectNode::out_RegMask() const {
1384   return RegMask::Empty;
1385 }
1386 
1387 uint SafePointScalarObjectNode::match_edge(uint idx) const {
1388   return 0;
1389 }
1390 
1391 SafePointScalarObjectNode*
1392 SafePointScalarObjectNode::clone(Dict* sosn_map) const {
1393   void* cached = (*sosn_map)[(void*)this];
1394   if (cached != NULL) {
1395     return (SafePointScalarObjectNode*)cached;
1396   }
1397   SafePointScalarObjectNode* res = (SafePointScalarObjectNode*)Node::clone();
1398   sosn_map->Insert((void*)this, (void*)res);
1399   return res;
1400 }
1401 
1402 
1403 #ifndef PRODUCT
1404 void SafePointScalarObjectNode::dump_spec(outputStream *st) const {
1405   st->print(" # fields@[%d..%d]", first_index(),
1406              first_index() + n_fields() - 1);
1407 }
1408 
1409 #endif
1410 
1411 //=============================================================================
1412 uint AllocateNode::size_of() const { return sizeof(*this); }
1413 
1414 AllocateNode::AllocateNode(Compile* C, const TypeFunc *atype,
1415                            Node *ctrl, Node *mem, Node *abio,
1416                            Node *size, Node *klass_node,
1417                            Node* initial_test, ValueTypeBaseNode* value_node)
1418   : CallNode(atype, NULL, TypeRawPtr::BOTTOM)
1419 {
1420   init_class_id(Class_Allocate);
1421   init_flags(Flag_is_macro);
1422   _is_scalar_replaceable = false;
1423   _is_non_escaping = false;
1424   _is_allocation_MemBar_redundant = false;
1425   Node *topnode = C->top();
1426 
1427   init_req( TypeFunc::Control  , ctrl );
1428   init_req( TypeFunc::I_O      , abio );
1429   init_req( TypeFunc::Memory   , mem );
1430   init_req( TypeFunc::ReturnAdr, topnode );
1431   init_req( TypeFunc::FramePtr , topnode );
1432   init_req( AllocSize          , size);
1433   init_req( KlassNode          , klass_node);
1434   init_req( InitialTest        , initial_test);
1435   init_req( ALength            , topnode);
1436   init_req( ValueNode          , value_node);
1437   C->add_macro_node(this);
1438 }
1439 
1440 void AllocateNode::compute_MemBar_redundancy(ciMethod* initializer)
1441 {
1442   assert(initializer != NULL &&
1443          initializer->is_initializer() &&
1444          !initializer->is_static(),
1445              "unexpected initializer method");
1446   BCEscapeAnalyzer* analyzer = initializer->get_bcea();
1447   if (analyzer == NULL) {
1448     return;
1449   }
1450 
1451   // Allocation node is first parameter in its initializer
1452   if (analyzer->is_arg_stack(0) || analyzer->is_arg_local(0)) {
1453     _is_allocation_MemBar_redundant = true;
1454   }
1455 }
1456 
1457 Node* AllocateNode::Ideal(PhaseGVN* phase, bool can_reshape) {
1458   // Check for unused value type allocation
1459   if (can_reshape && in(AllocateNode::ValueNode) != NULL &&
1460       outcnt() != 0 && result_cast() == NULL) {
1461     // Remove allocation by replacing the projection nodes with its inputs
1462     PhaseIterGVN* igvn = phase->is_IterGVN();
1463     CallProjections* projs = extract_projections(true, false);
1464     assert(projs->nb_resproj <= 1, "unexpected number of results");
1465     if (projs->fallthrough_catchproj != NULL) {
1466       igvn->replace_node(projs->fallthrough_catchproj, in(TypeFunc::Control));
1467     }
1468     if (projs->fallthrough_memproj != NULL) {
1469       igvn->replace_node(projs->fallthrough_memproj, in(TypeFunc::Memory));
1470     }
1471     if (projs->catchall_memproj != NULL) {
1472       igvn->replace_node(projs->catchall_memproj, phase->C->top());
1473     }
1474     if (projs->fallthrough_ioproj != NULL) {
1475       igvn->replace_node(projs->fallthrough_ioproj, in(TypeFunc::I_O));
1476     }
1477     if (projs->catchall_ioproj != NULL) {
1478       igvn->replace_node(projs->catchall_ioproj, phase->C->top());
1479     }
1480     if (projs->catchall_catchproj != NULL) {
1481       igvn->replace_node(projs->catchall_catchproj, phase->C->top());
1482     }
1483     if (projs->resproj[0] != NULL) {
1484       igvn->replace_node(projs->resproj[0], phase->C->top());
1485     }
1486     igvn->replace_node(this, phase->C->top());
1487     return NULL;
1488   }
1489 
1490   return CallNode::Ideal(phase, can_reshape);
1491 }
1492 
1493 //=============================================================================
1494 Node* AllocateArrayNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1495   Node* res = SafePointNode::Ideal(phase, can_reshape);
1496   if (res != NULL) {
1497     return res;
1498   }
1499   // Don't bother trying to transform a dead node
1500   if (in(0) && in(0)->is_top())  return NULL;
1501 
1502   const Type* type = phase->type(Ideal_length());
1503   if (type->isa_int() && type->is_int()->_hi < 0) {
1504     if (can_reshape) {
1505       PhaseIterGVN *igvn = phase->is_IterGVN();
1506       // Unreachable fall through path (negative array length),
1507       // the allocation can only throw so disconnect it.
1508       Node* proj = proj_out_or_null(TypeFunc::Control);
1509       Node* catchproj = NULL;
1510       if (proj != NULL) {
1511         for (DUIterator_Fast imax, i = proj->fast_outs(imax); i < imax; i++) {
1512           Node *cn = proj->fast_out(i);
1513           if (cn->is_Catch()) {
1514             catchproj = cn->as_Multi()->proj_out_or_null(CatchProjNode::fall_through_index);
1515             break;
1516           }
1517         }
1518       }
1519       if (catchproj != NULL && catchproj->outcnt() > 0 &&
1520           (catchproj->outcnt() > 1 ||
1521            catchproj->unique_out()->Opcode() != Op_Halt)) {
1522         assert(catchproj->is_CatchProj(), "must be a CatchProjNode");
1523         Node* nproj = catchproj->clone();
1524         igvn->register_new_node_with_optimizer(nproj);
1525 
1526         Node *frame = new ParmNode( phase->C->start(), TypeFunc::FramePtr );
1527         frame = phase->transform(frame);
1528         // Halt & Catch Fire
1529         Node *halt = new HaltNode( nproj, frame );
1530         phase->C->root()->add_req(halt);
1531         phase->transform(halt);
1532 
1533         igvn->replace_node(catchproj, phase->C->top());
1534         return this;
1535       }
1536     } else {
1537       // Can't correct it during regular GVN so register for IGVN
1538       phase->C->record_for_igvn(this);
1539     }
1540   }
1541   return NULL;
1542 }
1543 
1544 // Retrieve the length from the AllocateArrayNode. Narrow the type with a
1545 // CastII, if appropriate.  If we are not allowed to create new nodes, and
1546 // a CastII is appropriate, return NULL.
1547 Node *AllocateArrayNode::make_ideal_length(const TypeOopPtr* oop_type, PhaseTransform *phase, bool allow_new_nodes) {
1548   Node *length = in(AllocateNode::ALength);
1549   assert(length != NULL, "length is not null");
1550 
1551   const TypeInt* length_type = phase->find_int_type(length);
1552   const TypeAryPtr* ary_type = oop_type->isa_aryptr();
1553 
1554   if (ary_type != NULL && length_type != NULL) {
1555     const TypeInt* narrow_length_type = ary_type->narrow_size_type(length_type);
1556     if (narrow_length_type != length_type) {
1557       // Assert one of:
1558       //   - the narrow_length is 0
1559       //   - the narrow_length is not wider than length
1560       assert(narrow_length_type == TypeInt::ZERO ||
1561              length_type->is_con() && narrow_length_type->is_con() &&
1562                 (narrow_length_type->_hi <= length_type->_lo) ||
1563              (narrow_length_type->_hi <= length_type->_hi &&
1564               narrow_length_type->_lo >= length_type->_lo),
1565              "narrow type must be narrower than length type");
1566 
1567       // Return NULL if new nodes are not allowed
1568       if (!allow_new_nodes) return NULL;
1569       // Create a cast which is control dependent on the initialization to
1570       // propagate the fact that the array length must be positive.
1571       InitializeNode* init = initialization();
1572       assert(init != NULL, "initialization not found");
1573       length = new CastIINode(length, narrow_length_type);
1574       length->set_req(0, init->proj_out_or_null(0));
1575     }
1576   }
1577 
1578   return length;
1579 }
1580 
1581 //=============================================================================
1582 uint LockNode::size_of() const { return sizeof(*this); }
1583 
1584 // Redundant lock elimination
1585 //
1586 // There are various patterns of locking where we release and
1587 // immediately reacquire a lock in a piece of code where no operations
1588 // occur in between that would be observable.  In those cases we can
1589 // skip releasing and reacquiring the lock without violating any
1590 // fairness requirements.  Doing this around a loop could cause a lock
1591 // to be held for a very long time so we concentrate on non-looping
1592 // control flow.  We also require that the operations are fully
1593 // redundant meaning that we don't introduce new lock operations on
1594 // some paths so to be able to eliminate it on others ala PRE.  This
1595 // would probably require some more extensive graph manipulation to
1596 // guarantee that the memory edges were all handled correctly.
1597 //
1598 // Assuming p is a simple predicate which can't trap in any way and s
1599 // is a synchronized method consider this code:
1600 //
1601 //   s();
1602 //   if (p)
1603 //     s();
1604 //   else
1605 //     s();
1606 //   s();
1607 //
1608 // 1. The unlocks of the first call to s can be eliminated if the
1609 // locks inside the then and else branches are eliminated.
1610 //
1611 // 2. The unlocks of the then and else branches can be eliminated if
1612 // the lock of the final call to s is eliminated.
1613 //
1614 // Either of these cases subsumes the simple case of sequential control flow
1615 //
1616 // Addtionally we can eliminate versions without the else case:
1617 //
1618 //   s();
1619 //   if (p)
1620 //     s();
1621 //   s();
1622 //
1623 // 3. In this case we eliminate the unlock of the first s, the lock
1624 // and unlock in the then case and the lock in the final s.
1625 //
1626 // Note also that in all these cases the then/else pieces don't have
1627 // to be trivial as long as they begin and end with synchronization
1628 // operations.
1629 //
1630 //   s();
1631 //   if (p)
1632 //     s();
1633 //     f();
1634 //     s();
1635 //   s();
1636 //
1637 // The code will work properly for this case, leaving in the unlock
1638 // before the call to f and the relock after it.
1639 //
1640 // A potentially interesting case which isn't handled here is when the
1641 // locking is partially redundant.
1642 //
1643 //   s();
1644 //   if (p)
1645 //     s();
1646 //
1647 // This could be eliminated putting unlocking on the else case and
1648 // eliminating the first unlock and the lock in the then side.
1649 // Alternatively the unlock could be moved out of the then side so it
1650 // was after the merge and the first unlock and second lock
1651 // eliminated.  This might require less manipulation of the memory
1652 // state to get correct.
1653 //
1654 // Additionally we might allow work between a unlock and lock before
1655 // giving up eliminating the locks.  The current code disallows any
1656 // conditional control flow between these operations.  A formulation
1657 // similar to partial redundancy elimination computing the
1658 // availability of unlocking and the anticipatability of locking at a
1659 // program point would allow detection of fully redundant locking with
1660 // some amount of work in between.  I'm not sure how often I really
1661 // think that would occur though.  Most of the cases I've seen
1662 // indicate it's likely non-trivial work would occur in between.
1663 // There may be other more complicated constructs where we could
1664 // eliminate locking but I haven't seen any others appear as hot or
1665 // interesting.
1666 //
1667 // Locking and unlocking have a canonical form in ideal that looks
1668 // roughly like this:
1669 //
1670 //              <obj>
1671 //                | \\------+
1672 //                |  \       \
1673 //                | BoxLock   \
1674 //                |  |   |     \
1675 //                |  |    \     \
1676 //                |  |   FastLock
1677 //                |  |   /
1678 //                |  |  /
1679 //                |  |  |
1680 //
1681 //               Lock
1682 //                |
1683 //            Proj #0
1684 //                |
1685 //            MembarAcquire
1686 //                |
1687 //            Proj #0
1688 //
1689 //            MembarRelease
1690 //                |
1691 //            Proj #0
1692 //                |
1693 //              Unlock
1694 //                |
1695 //            Proj #0
1696 //
1697 //
1698 // This code proceeds by processing Lock nodes during PhaseIterGVN
1699 // and searching back through its control for the proper code
1700 // patterns.  Once it finds a set of lock and unlock operations to
1701 // eliminate they are marked as eliminatable which causes the
1702 // expansion of the Lock and Unlock macro nodes to make the operation a NOP
1703 //
1704 //=============================================================================
1705 
1706 //
1707 // Utility function to skip over uninteresting control nodes.  Nodes skipped are:
1708 //   - copy regions.  (These may not have been optimized away yet.)
1709 //   - eliminated locking nodes
1710 //
1711 static Node *next_control(Node *ctrl) {
1712   if (ctrl == NULL)
1713     return NULL;
1714   while (1) {
1715     if (ctrl->is_Region()) {
1716       RegionNode *r = ctrl->as_Region();
1717       Node *n = r->is_copy();
1718       if (n == NULL)
1719         break;  // hit a region, return it
1720       else
1721         ctrl = n;
1722     } else if (ctrl->is_Proj()) {
1723       Node *in0 = ctrl->in(0);
1724       if (in0->is_AbstractLock() && in0->as_AbstractLock()->is_eliminated()) {
1725         ctrl = in0->in(0);
1726       } else {
1727         break;
1728       }
1729     } else {
1730       break; // found an interesting control
1731     }
1732   }
1733   return ctrl;
1734 }
1735 //
1736 // Given a control, see if it's the control projection of an Unlock which
1737 // operating on the same object as lock.
1738 //
1739 bool AbstractLockNode::find_matching_unlock(const Node* ctrl, LockNode* lock,
1740                                             GrowableArray<AbstractLockNode*> &lock_ops) {
1741   ProjNode *ctrl_proj = (ctrl->is_Proj()) ? ctrl->as_Proj() : NULL;
1742   if (ctrl_proj != NULL && ctrl_proj->_con == TypeFunc::Control) {
1743     Node *n = ctrl_proj->in(0);
1744     if (n != NULL && n->is_Unlock()) {
1745       UnlockNode *unlock = n->as_Unlock();
1746       if (lock->obj_node()->eqv_uncast(unlock->obj_node()) &&
1747           BoxLockNode::same_slot(lock->box_node(), unlock->box_node()) &&
1748           !unlock->is_eliminated()) {
1749         lock_ops.append(unlock);
1750         return true;
1751       }
1752     }
1753   }
1754   return false;
1755 }
1756 
1757 //
1758 // Find the lock matching an unlock.  Returns null if a safepoint
1759 // or complicated control is encountered first.
1760 LockNode *AbstractLockNode::find_matching_lock(UnlockNode* unlock) {
1761   LockNode *lock_result = NULL;
1762   // find the matching lock, or an intervening safepoint
1763   Node *ctrl = next_control(unlock->in(0));
1764   while (1) {
1765     assert(ctrl != NULL, "invalid control graph");
1766     assert(!ctrl->is_Start(), "missing lock for unlock");
1767     if (ctrl->is_top()) break;  // dead control path
1768     if (ctrl->is_Proj()) ctrl = ctrl->in(0);
1769     if (ctrl->is_SafePoint()) {
1770         break;  // found a safepoint (may be the lock we are searching for)
1771     } else if (ctrl->is_Region()) {
1772       // Check for a simple diamond pattern.  Punt on anything more complicated
1773       if (ctrl->req() == 3 && ctrl->in(1) != NULL && ctrl->in(2) != NULL) {
1774         Node *in1 = next_control(ctrl->in(1));
1775         Node *in2 = next_control(ctrl->in(2));
1776         if (((in1->is_IfTrue() && in2->is_IfFalse()) ||
1777              (in2->is_IfTrue() && in1->is_IfFalse())) && (in1->in(0) == in2->in(0))) {
1778           ctrl = next_control(in1->in(0)->in(0));
1779         } else {
1780           break;
1781         }
1782       } else {
1783         break;
1784       }
1785     } else {
1786       ctrl = next_control(ctrl->in(0));  // keep searching
1787     }
1788   }
1789   if (ctrl->is_Lock()) {
1790     LockNode *lock = ctrl->as_Lock();
1791     if (lock->obj_node()->eqv_uncast(unlock->obj_node()) &&
1792         BoxLockNode::same_slot(lock->box_node(), unlock->box_node())) {
1793       lock_result = lock;
1794     }
1795   }
1796   return lock_result;
1797 }
1798 
1799 // This code corresponds to case 3 above.
1800 
1801 bool AbstractLockNode::find_lock_and_unlock_through_if(Node* node, LockNode* lock,
1802                                                        GrowableArray<AbstractLockNode*> &lock_ops) {
1803   Node* if_node = node->in(0);
1804   bool  if_true = node->is_IfTrue();
1805 
1806   if (if_node->is_If() && if_node->outcnt() == 2 && (if_true || node->is_IfFalse())) {
1807     Node *lock_ctrl = next_control(if_node->in(0));
1808     if (find_matching_unlock(lock_ctrl, lock, lock_ops)) {
1809       Node* lock1_node = NULL;
1810       ProjNode* proj = if_node->as_If()->proj_out(!if_true);
1811       if (if_true) {
1812         if (proj->is_IfFalse() && proj->outcnt() == 1) {
1813           lock1_node = proj->unique_out();
1814         }
1815       } else {
1816         if (proj->is_IfTrue() && proj->outcnt() == 1) {
1817           lock1_node = proj->unique_out();
1818         }
1819       }
1820       if (lock1_node != NULL && lock1_node->is_Lock()) {
1821         LockNode *lock1 = lock1_node->as_Lock();
1822         if (lock->obj_node()->eqv_uncast(lock1->obj_node()) &&
1823             BoxLockNode::same_slot(lock->box_node(), lock1->box_node()) &&
1824             !lock1->is_eliminated()) {
1825           lock_ops.append(lock1);
1826           return true;
1827         }
1828       }
1829     }
1830   }
1831 
1832   lock_ops.trunc_to(0);
1833   return false;
1834 }
1835 
1836 bool AbstractLockNode::find_unlocks_for_region(const RegionNode* region, LockNode* lock,
1837                                GrowableArray<AbstractLockNode*> &lock_ops) {
1838   // check each control merging at this point for a matching unlock.
1839   // in(0) should be self edge so skip it.
1840   for (int i = 1; i < (int)region->req(); i++) {
1841     Node *in_node = next_control(region->in(i));
1842     if (in_node != NULL) {
1843       if (find_matching_unlock(in_node, lock, lock_ops)) {
1844         // found a match so keep on checking.
1845         continue;
1846       } else if (find_lock_and_unlock_through_if(in_node, lock, lock_ops)) {
1847         continue;
1848       }
1849 
1850       // If we fall through to here then it was some kind of node we
1851       // don't understand or there wasn't a matching unlock, so give
1852       // up trying to merge locks.
1853       lock_ops.trunc_to(0);
1854       return false;
1855     }
1856   }
1857   return true;
1858 
1859 }
1860 
1861 #ifndef PRODUCT
1862 //
1863 // Create a counter which counts the number of times this lock is acquired
1864 //
1865 void AbstractLockNode::create_lock_counter(JVMState* state) {
1866   _counter = OptoRuntime::new_named_counter(state, NamedCounter::LockCounter);
1867 }
1868 
1869 void AbstractLockNode::set_eliminated_lock_counter() {
1870   if (_counter) {
1871     // Update the counter to indicate that this lock was eliminated.
1872     // The counter update code will stay around even though the
1873     // optimizer will eliminate the lock operation itself.
1874     _counter->set_tag(NamedCounter::EliminatedLockCounter);
1875   }
1876 }
1877 
1878 const char* AbstractLockNode::_kind_names[] = {"Regular", "NonEscObj", "Coarsened", "Nested"};
1879 
1880 void AbstractLockNode::dump_spec(outputStream* st) const {
1881   st->print("%s ", _kind_names[_kind]);
1882   CallNode::dump_spec(st);
1883 }
1884 
1885 void AbstractLockNode::dump_compact_spec(outputStream* st) const {
1886   st->print("%s", _kind_names[_kind]);
1887 }
1888 
1889 // The related set of lock nodes includes the control boundary.
1890 void AbstractLockNode::related(GrowableArray<Node*> *in_rel, GrowableArray<Node*> *out_rel, bool compact) const {
1891   if (compact) {
1892       this->collect_nodes(in_rel, 1, false, false);
1893     } else {
1894       this->collect_nodes_in_all_data(in_rel, true);
1895     }
1896     this->collect_nodes(out_rel, -2, false, false);
1897 }
1898 #endif
1899 
1900 //=============================================================================
1901 Node *LockNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1902 
1903   // perform any generic optimizations first (returns 'this' or NULL)
1904   Node *result = SafePointNode::Ideal(phase, can_reshape);
1905   if (result != NULL)  return result;
1906   // Don't bother trying to transform a dead node
1907   if (in(0) && in(0)->is_top())  return NULL;
1908 
1909   // Now see if we can optimize away this lock.  We don't actually
1910   // remove the locking here, we simply set the _eliminate flag which
1911   // prevents macro expansion from expanding the lock.  Since we don't
1912   // modify the graph, the value returned from this function is the
1913   // one computed above.
1914   if (can_reshape && EliminateLocks && !is_non_esc_obj()) {
1915     //
1916     // If we are locking an unescaped object, the lock/unlock is unnecessary
1917     //
1918     ConnectionGraph *cgr = phase->C->congraph();
1919     if (cgr != NULL && cgr->not_global_escape(obj_node())) {
1920       assert(!is_eliminated() || is_coarsened(), "sanity");
1921       // The lock could be marked eliminated by lock coarsening
1922       // code during first IGVN before EA. Replace coarsened flag
1923       // to eliminate all associated locks/unlocks.
1924 #ifdef ASSERT
1925       this->log_lock_optimization(phase->C,"eliminate_lock_set_non_esc1");
1926 #endif
1927       this->set_non_esc_obj();
1928       return result;
1929     }
1930 
1931     //
1932     // Try lock coarsening
1933     //
1934     PhaseIterGVN* iter = phase->is_IterGVN();
1935     if (iter != NULL && !is_eliminated()) {
1936 
1937       GrowableArray<AbstractLockNode*>   lock_ops;
1938 
1939       Node *ctrl = next_control(in(0));
1940 
1941       // now search back for a matching Unlock
1942       if (find_matching_unlock(ctrl, this, lock_ops)) {
1943         // found an unlock directly preceding this lock.  This is the
1944         // case of single unlock directly control dependent on a
1945         // single lock which is the trivial version of case 1 or 2.
1946       } else if (ctrl->is_Region() ) {
1947         if (find_unlocks_for_region(ctrl->as_Region(), this, lock_ops)) {
1948         // found lock preceded by multiple unlocks along all paths
1949         // joining at this point which is case 3 in description above.
1950         }
1951       } else {
1952         // see if this lock comes from either half of an if and the
1953         // predecessors merges unlocks and the other half of the if
1954         // performs a lock.
1955         if (find_lock_and_unlock_through_if(ctrl, this, lock_ops)) {
1956           // found unlock splitting to an if with locks on both branches.
1957         }
1958       }
1959 
1960       if (lock_ops.length() > 0) {
1961         // add ourselves to the list of locks to be eliminated.
1962         lock_ops.append(this);
1963 
1964   #ifndef PRODUCT
1965         if (PrintEliminateLocks) {
1966           int locks = 0;
1967           int unlocks = 0;
1968           for (int i = 0; i < lock_ops.length(); i++) {
1969             AbstractLockNode* lock = lock_ops.at(i);
1970             if (lock->Opcode() == Op_Lock)
1971               locks++;
1972             else
1973               unlocks++;
1974             if (Verbose) {
1975               lock->dump(1);
1976             }
1977           }
1978           tty->print_cr("***Eliminated %d unlocks and %d locks", unlocks, locks);
1979         }
1980   #endif
1981 
1982         // for each of the identified locks, mark them
1983         // as eliminatable
1984         for (int i = 0; i < lock_ops.length(); i++) {
1985           AbstractLockNode* lock = lock_ops.at(i);
1986 
1987           // Mark it eliminated by coarsening and update any counters
1988 #ifdef ASSERT
1989           lock->log_lock_optimization(phase->C, "eliminate_lock_set_coarsened");
1990 #endif
1991           lock->set_coarsened();
1992         }
1993       } else if (ctrl->is_Region() &&
1994                  iter->_worklist.member(ctrl)) {
1995         // We weren't able to find any opportunities but the region this
1996         // lock is control dependent on hasn't been processed yet so put
1997         // this lock back on the worklist so we can check again once any
1998         // region simplification has occurred.
1999         iter->_worklist.push(this);
2000       }
2001     }
2002   }
2003 
2004   return result;
2005 }
2006 
2007 //=============================================================================
2008 bool LockNode::is_nested_lock_region() {
2009   return is_nested_lock_region(NULL);
2010 }
2011 
2012 // p is used for access to compilation log; no logging if NULL
2013 bool LockNode::is_nested_lock_region(Compile * c) {
2014   BoxLockNode* box = box_node()->as_BoxLock();
2015   int stk_slot = box->stack_slot();
2016   if (stk_slot <= 0) {
2017 #ifdef ASSERT
2018     this->log_lock_optimization(c, "eliminate_lock_INLR_1");
2019 #endif
2020     return false; // External lock or it is not Box (Phi node).
2021   }
2022 
2023   // Ignore complex cases: merged locks or multiple locks.
2024   Node* obj = obj_node();
2025   LockNode* unique_lock = NULL;
2026   if (!box->is_simple_lock_region(&unique_lock, obj)) {
2027 #ifdef ASSERT
2028     this->log_lock_optimization(c, "eliminate_lock_INLR_2a");
2029 #endif
2030     return false;
2031   }
2032   if (unique_lock != this) {
2033 #ifdef ASSERT
2034     this->log_lock_optimization(c, "eliminate_lock_INLR_2b");
2035 #endif
2036     return false;
2037   }
2038 
2039   // Look for external lock for the same object.
2040   SafePointNode* sfn = this->as_SafePoint();
2041   JVMState* youngest_jvms = sfn->jvms();
2042   int max_depth = youngest_jvms->depth();
2043   for (int depth = 1; depth <= max_depth; depth++) {
2044     JVMState* jvms = youngest_jvms->of_depth(depth);
2045     int num_mon  = jvms->nof_monitors();
2046     // Loop over monitors
2047     for (int idx = 0; idx < num_mon; idx++) {
2048       Node* obj_node = sfn->monitor_obj(jvms, idx);
2049       BoxLockNode* box_node = sfn->monitor_box(jvms, idx)->as_BoxLock();
2050       if ((box_node->stack_slot() < stk_slot) && obj_node->eqv_uncast(obj)) {
2051         return true;
2052       }
2053     }
2054   }
2055 #ifdef ASSERT
2056   this->log_lock_optimization(c, "eliminate_lock_INLR_3");
2057 #endif
2058   return false;
2059 }
2060 
2061 //=============================================================================
2062 uint UnlockNode::size_of() const { return sizeof(*this); }
2063 
2064 //=============================================================================
2065 Node *UnlockNode::Ideal(PhaseGVN *phase, bool can_reshape) {
2066 
2067   // perform any generic optimizations first (returns 'this' or NULL)
2068   Node *result = SafePointNode::Ideal(phase, can_reshape);
2069   if (result != NULL)  return result;
2070   // Don't bother trying to transform a dead node
2071   if (in(0) && in(0)->is_top())  return NULL;
2072 
2073   // Now see if we can optimize away this unlock.  We don't actually
2074   // remove the unlocking here, we simply set the _eliminate flag which
2075   // prevents macro expansion from expanding the unlock.  Since we don't
2076   // modify the graph, the value returned from this function is the
2077   // one computed above.
2078   // Escape state is defined after Parse phase.
2079   if (can_reshape && EliminateLocks && !is_non_esc_obj()) {
2080     //
2081     // If we are unlocking an unescaped object, the lock/unlock is unnecessary.
2082     //
2083     ConnectionGraph *cgr = phase->C->congraph();
2084     if (cgr != NULL && cgr->not_global_escape(obj_node())) {
2085       assert(!is_eliminated() || is_coarsened(), "sanity");
2086       // The lock could be marked eliminated by lock coarsening
2087       // code during first IGVN before EA. Replace coarsened flag
2088       // to eliminate all associated locks/unlocks.
2089 #ifdef ASSERT
2090       this->log_lock_optimization(phase->C, "eliminate_lock_set_non_esc2");
2091 #endif
2092       this->set_non_esc_obj();
2093     }
2094   }
2095   return result;
2096 }
2097 
2098 const char * AbstractLockNode::kind_as_string() const {
2099   return is_coarsened()   ? "coarsened" :
2100          is_nested()      ? "nested" :
2101          is_non_esc_obj() ? "non_escaping" :
2102          "?";
2103 }
2104 
2105 void AbstractLockNode::log_lock_optimization(Compile *C, const char * tag)  const {
2106   if (C == NULL) {
2107     return;
2108   }
2109   CompileLog* log = C->log();
2110   if (log != NULL) {
2111     log->begin_head("%s lock='%d' compile_id='%d' class_id='%s' kind='%s'",
2112           tag, is_Lock(), C->compile_id(),
2113           is_Unlock() ? "unlock" : is_Lock() ? "lock" : "?",
2114           kind_as_string());
2115     log->stamp();
2116     log->end_head();
2117     JVMState* p = is_Unlock() ? (as_Unlock()->dbg_jvms()) : jvms();
2118     while (p != NULL) {
2119       log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method()));
2120       p = p->caller();
2121     }
2122     log->tail(tag);
2123   }
2124 }
2125 
2126 bool CallNode::may_modify_arraycopy_helper(const TypeOopPtr* dest_t, const TypeOopPtr *t_oop, PhaseTransform *phase) {
2127   if (dest_t->is_known_instance() && t_oop->is_known_instance()) {
2128     return dest_t->instance_id() == t_oop->instance_id();
2129   }
2130 
2131   if (dest_t->isa_instptr() && !dest_t->klass()->equals(phase->C->env()->Object_klass())) {
2132     // clone
2133     if (t_oop->isa_aryptr()) {
2134       return false;
2135     }
2136     if (!t_oop->isa_instptr()) {
2137       return true;
2138     }
2139     if (dest_t->klass()->is_subtype_of(t_oop->klass()) || t_oop->klass()->is_subtype_of(dest_t->klass())) {
2140       return true;
2141     }
2142     // unrelated
2143     return false;
2144   }
2145 
2146   if (dest_t->isa_aryptr()) {
2147     // arraycopy or array clone
2148     if (t_oop->isa_instptr()) {
2149       return false;
2150     }
2151     if (!t_oop->isa_aryptr()) {
2152       return true;
2153     }
2154 
2155     const Type* elem = dest_t->is_aryptr()->elem();
2156     if (elem == Type::BOTTOM) {
2157       // An array but we don't know what elements are
2158       return true;
2159     }
2160 
2161     dest_t = dest_t->is_aryptr()->with_field_offset(Type::OffsetBot)->add_offset(Type::OffsetBot)->is_oopptr();
2162     t_oop = t_oop->is_aryptr()->with_field_offset(Type::OffsetBot);
2163     uint dest_alias = phase->C->get_alias_index(dest_t);
2164     uint t_oop_alias = phase->C->get_alias_index(t_oop);
2165 
2166     return dest_alias == t_oop_alias;
2167   }
2168 
2169   return true;
2170 }
2171