1 /*
   2  * Copyright (c) 2015, 2019, 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 #include "precompiled.hpp"
  25 #include "opto/compile.hpp"
  26 #include "opto/castnode.hpp"
  27 #include "opto/graphKit.hpp"
  28 #include "opto/idealKit.hpp"
  29 #include "opto/loopnode.hpp"
  30 #include "opto/macro.hpp"
  31 #include "opto/node.hpp"
  32 #include "opto/type.hpp"
  33 #include "utilities/macros.hpp"
  34 #include "gc/z/zBarrierSet.hpp"
  35 #include "gc/z/c2/zBarrierSetC2.hpp"
  36 #include "gc/z/zThreadLocalData.hpp"
  37 #include "gc/z/zBarrierSetRuntime.hpp"
  38 
  39 ZBarrierSetC2State::ZBarrierSetC2State(Arena* comp_arena)
  40   : _load_barrier_nodes(new (comp_arena) GrowableArray<LoadBarrierNode*>(comp_arena, 8,  0, NULL)) {}
  41 
  42 int ZBarrierSetC2State::load_barrier_count() const {
  43   return _load_barrier_nodes->length();
  44 }
  45 
  46 void ZBarrierSetC2State::add_load_barrier_node(LoadBarrierNode * n) {
  47   assert(!_load_barrier_nodes->contains(n), " duplicate entry in expand list");
  48   _load_barrier_nodes->append(n);
  49 }
  50 
  51 void ZBarrierSetC2State::remove_load_barrier_node(LoadBarrierNode * n) {
  52   // this function may be called twice for a node so check
  53   // that the node is in the array before attempting to remove it
  54   if (_load_barrier_nodes->contains(n)) {
  55     _load_barrier_nodes->remove(n);
  56   }
  57 }
  58 
  59 LoadBarrierNode* ZBarrierSetC2State::load_barrier_node(int idx) const {
  60   return _load_barrier_nodes->at(idx);
  61 }
  62 
  63 void* ZBarrierSetC2::create_barrier_state(Arena* comp_arena) const {
  64   return new(comp_arena) ZBarrierSetC2State(comp_arena);
  65 }
  66 
  67 ZBarrierSetC2State* ZBarrierSetC2::state() const {
  68   return reinterpret_cast<ZBarrierSetC2State*>(Compile::current()->barrier_set_state());
  69 }
  70 
  71 bool ZBarrierSetC2::is_gc_barrier_node(Node* node) const {
  72   // 1. This step follows potential oop projections of a load barrier before expansion
  73   if (node->is_Proj()) {
  74     node = node->in(0);
  75   }
  76 
  77   // 2. This step checks for unexpanded load barriers
  78   if (node->is_LoadBarrier()) {
  79     return true;
  80   }
  81 
  82   // 3. This step checks for the phi corresponding to an optimized load barrier expansion
  83   if (node->is_Phi()) {
  84     PhiNode* phi = node->as_Phi();
  85     Node* n = phi->in(1);
  86     if (n != NULL && (n->is_LoadBarrierSlowReg() ||  n->is_LoadBarrierWeakSlowReg())) {
  87       return true;
  88     }
  89   }
  90 
  91   return false;
  92 }
  93 
  94 void ZBarrierSetC2::register_potential_barrier_node(Node* node) const {
  95   if (node->is_LoadBarrier()) {
  96     state()->add_load_barrier_node(node->as_LoadBarrier());
  97   }
  98 }
  99 
 100 void ZBarrierSetC2::unregister_potential_barrier_node(Node* node) const {
 101   if (node->is_LoadBarrier()) {
 102     state()->remove_load_barrier_node(node->as_LoadBarrier());
 103   }
 104 }
 105 
 106 void ZBarrierSetC2::eliminate_useless_gc_barriers(Unique_Node_List &useful) const {
 107   // Remove useless LoadBarrier nodes
 108   ZBarrierSetC2State* s = state();
 109   for (int i = s->load_barrier_count()-1; i >= 0; i--) {
 110     LoadBarrierNode* n = s->load_barrier_node(i);
 111     if (!useful.member(n)) {
 112       unregister_potential_barrier_node(n);
 113     }
 114   }
 115 }
 116 
 117 void ZBarrierSetC2::enqueue_useful_gc_barrier(Unique_Node_List &worklist, Node* node) const {
 118   if (node->is_LoadBarrier() && !node->as_LoadBarrier()->has_true_uses()) {
 119     worklist.push(node);
 120   }
 121 }
 122 
 123 void ZBarrierSetC2::find_dominating_barriers(PhaseIterGVN& igvn) {
 124   // Look for dominating barriers on the same address only once all
 125   // other loop opts are over: loop opts may cause a safepoint to be
 126   // inserted between a barrier and its dominating barrier.
 127   Compile* C = Compile::current();
 128   ZBarrierSetC2* bs = (ZBarrierSetC2*)BarrierSet::barrier_set()->barrier_set_c2();
 129   ZBarrierSetC2State* s = bs->state();
 130   if (s->load_barrier_count() >= 2) {
 131     Compile::TracePhase tp("idealLoop", &C->timers[Phase::_t_idealLoop]);
 132     PhaseIdealLoop ideal_loop(igvn, LoopOptsLastRound);
 133     if (C->major_progress()) C->print_method(PHASE_PHASEIDEALLOOP_ITERATIONS, 2);
 134   }
 135 }
 136 
 137 void ZBarrierSetC2::add_users_to_worklist(Unique_Node_List* worklist) const {
 138   // Permanent temporary workaround
 139   // Loadbarriers may have non-obvious dead uses keeping them alive during parsing. The use is
 140   // removed by RemoveUseless (after parsing, before optimize) but the barriers won't be added to
 141   // the worklist. Unless we add them explicitly they are not guaranteed to end up there.
 142   ZBarrierSetC2State* s = state();
 143 
 144   for (int i = 0; i < s->load_barrier_count(); i++) {
 145     LoadBarrierNode* n = s->load_barrier_node(i);
 146     worklist->push(n);
 147   }
 148 }
 149 
 150 const TypeFunc* ZBarrierSetC2::load_barrier_Type() const {
 151   const Type** fields;
 152 
 153   // Create input types (domain)
 154   fields = TypeTuple::fields(2);
 155   fields[TypeFunc::Parms+0] = TypeInstPtr::NOTNULL;
 156   fields[TypeFunc::Parms+1] = TypeOopPtr::BOTTOM;
 157   const TypeTuple *domain = TypeTuple::make(TypeFunc::Parms+2, fields);
 158 
 159   // Create result type (range)
 160   fields = TypeTuple::fields(1);
 161   fields[TypeFunc::Parms+0] = TypeInstPtr::BOTTOM;
 162   const TypeTuple *range = TypeTuple::make(TypeFunc::Parms+1, fields);
 163 
 164   return TypeFunc::make(domain, range);
 165 }
 166 
 167 // == LoadBarrierNode ==
 168 
 169 LoadBarrierNode::LoadBarrierNode(Compile* C,
 170                                  Node* c,
 171                                  Node* mem,
 172                                  Node* val,
 173                                  Node* adr,
 174                                  bool weak,
 175                                  bool writeback,
 176                                  bool oop_reload_allowed) :
 177     MultiNode(Number_of_Inputs),
 178     _weak(weak),
 179     _writeback(writeback),
 180     _oop_reload_allowed(oop_reload_allowed) {
 181   init_req(Control, c);
 182   init_req(Memory, mem);
 183   init_req(Oop, val);
 184   init_req(Address, adr);
 185   init_req(Similar, C->top());
 186 
 187   init_class_id(Class_LoadBarrier);
 188   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
 189   bs->register_potential_barrier_node(this);
 190 }
 191 
 192 uint LoadBarrierNode::size_of() const {
 193   return sizeof(*this);
 194 }
 195 
 196 uint LoadBarrierNode::cmp(const Node& n) const {
 197   ShouldNotReachHere();
 198   return 0;
 199 }
 200 
 201 const Type *LoadBarrierNode::bottom_type() const {
 202   const Type** floadbarrier = (const Type **)(Compile::current()->type_arena()->Amalloc_4((Number_of_Outputs)*sizeof(Type*)));
 203   Node* in_oop = in(Oop);
 204   floadbarrier[Control] = Type::CONTROL;
 205   floadbarrier[Memory] = Type::MEMORY;
 206   floadbarrier[Oop] = in_oop == NULL ? Type::TOP : in_oop->bottom_type();
 207   return TypeTuple::make(Number_of_Outputs, floadbarrier);
 208 }
 209 
 210 const TypePtr* LoadBarrierNode::adr_type() const {
 211   return TypeRawPtr::BOTTOM;
 212 }
 213 
 214 const Type *LoadBarrierNode::Value(PhaseGVN *phase) const {
 215   const Type** floadbarrier = (const Type **)(phase->C->type_arena()->Amalloc_4((Number_of_Outputs)*sizeof(Type*)));
 216   const Type* val_t = phase->type(in(Oop));
 217   floadbarrier[Control] = Type::CONTROL;
 218   floadbarrier[Memory] = Type::MEMORY;
 219   floadbarrier[Oop] = val_t;
 220   return TypeTuple::make(Number_of_Outputs, floadbarrier);
 221 }
 222 
 223 bool LoadBarrierNode::is_dominator(PhaseIdealLoop* phase, bool linear_only, Node *d, Node *n) {
 224   if (phase != NULL) {
 225     return phase->is_dominator(d, n);
 226   }
 227 
 228   for (int i = 0; i < 10 && n != NULL; i++) {
 229     n = IfNode::up_one_dom(n, linear_only);
 230     if (n == d) {
 231       return true;
 232     }
 233   }
 234 
 235   return false;
 236 }
 237 
 238 LoadBarrierNode* LoadBarrierNode::has_dominating_barrier(PhaseIdealLoop* phase, bool linear_only, bool look_for_similar) {
 239   Node* val = in(LoadBarrierNode::Oop);
 240   if (in(Similar)->is_Proj() && in(Similar)->in(0)->is_LoadBarrier()) {
 241     LoadBarrierNode* lb = in(Similar)->in(0)->as_LoadBarrier();
 242     assert(lb->in(Address) == in(Address), "");
 243     // Load barrier on Similar edge dominates so if it now has the Oop field it can replace this barrier.
 244     if (lb->in(Oop) == in(Oop)) {
 245       return lb;
 246     }
 247     // Follow chain of load barrier through Similar edges
 248     while (!lb->in(Similar)->is_top()) {
 249       lb = lb->in(Similar)->in(0)->as_LoadBarrier();
 250       assert(lb->in(Address) == in(Address), "");
 251     }
 252     if (lb != in(Similar)->in(0)) {
 253       return lb;
 254     }
 255   }
 256   for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
 257     Node* u = val->fast_out(i);
 258     if (u != this && u->is_LoadBarrier() && u->in(Oop) == val && u->as_LoadBarrier()->has_true_uses()) {
 259       Node* this_ctrl = in(LoadBarrierNode::Control);
 260       Node* other_ctrl = u->in(LoadBarrierNode::Control);
 261       if (is_dominator(phase, linear_only, other_ctrl, this_ctrl)) {
 262         return u->as_LoadBarrier();
 263       }
 264     }
 265   }
 266 
 267   if (ZVerifyLoadBarriers || can_be_eliminated()) {
 268     return NULL;
 269   }
 270 
 271   if (!look_for_similar) {
 272     return NULL;
 273   }
 274 
 275   Node* addr = in(LoadBarrierNode::Address);
 276   for (DUIterator_Fast imax, i = addr->fast_outs(imax); i < imax; i++) {
 277     Node* u = addr->fast_out(i);
 278     if (u != this && u->is_LoadBarrier() && u->as_LoadBarrier()->has_true_uses()) {
 279       Node* this_ctrl = in(LoadBarrierNode::Control);
 280       Node* other_ctrl = u->in(LoadBarrierNode::Control);
 281       if (is_dominator(phase, linear_only, other_ctrl, this_ctrl)) {
 282         ResourceMark rm;
 283         Unique_Node_List wq;
 284         wq.push(in(LoadBarrierNode::Control));
 285         bool ok = true;
 286         bool dom_found = false;
 287         for (uint next = 0; next < wq.size(); ++next) {
 288           Node *n = wq.at(next);
 289           if (n->is_top()) {
 290             return NULL;
 291           }
 292           assert(n->is_CFG(), "");
 293           if (n->is_SafePoint()) {
 294             ok = false;
 295             break;
 296           }
 297           if (n == u) {
 298             dom_found = true;
 299             continue;
 300           }
 301           if (n->is_Region()) {
 302             for (uint i = 1; i < n->req(); i++) {
 303               Node* m = n->in(i);
 304               if (m != NULL) {
 305                 wq.push(m);
 306               }
 307             }
 308           } else {
 309             Node* m = n->in(0);
 310             if (m != NULL) {
 311               wq.push(m);
 312             }
 313           }
 314         }
 315         if (ok) {
 316           assert(dom_found, "");
 317           return u->as_LoadBarrier();;
 318         }
 319         break;
 320       }
 321     }
 322   }
 323 
 324   return NULL;
 325 }
 326 
 327 void LoadBarrierNode::push_dominated_barriers(PhaseIterGVN* igvn) const {
 328   // Change to that barrier may affect a dominated barrier so re-push those
 329   Node* val = in(LoadBarrierNode::Oop);
 330 
 331   for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
 332     Node* u = val->fast_out(i);
 333     if (u != this && u->is_LoadBarrier() && u->in(Oop) == val) {
 334       Node* this_ctrl = in(Control);
 335       Node* other_ctrl = u->in(Control);
 336       if (is_dominator(NULL, false, this_ctrl, other_ctrl)) {
 337         igvn->_worklist.push(u);
 338       }
 339     }
 340 
 341     Node* addr = in(LoadBarrierNode::Address);
 342     for (DUIterator_Fast imax, i = addr->fast_outs(imax); i < imax; i++) {
 343       Node* u = addr->fast_out(i);
 344       if (u != this && u->is_LoadBarrier() && u->in(Similar)->is_top()) {
 345         Node* this_ctrl = in(Control);
 346         Node* other_ctrl = u->in(Control);
 347         if (is_dominator(NULL, false, this_ctrl, other_ctrl)) {
 348           igvn->_worklist.push(u);
 349         }
 350       }
 351     }
 352   }
 353 }
 354 
 355 Node *LoadBarrierNode::Identity(PhaseGVN *phase) {
 356   if (!phase->C->directive()->ZOptimizeLoadBarriersOption) {
 357     return this;
 358   }
 359 
 360   bool redundant_addr = false;
 361   LoadBarrierNode* dominating_barrier = has_dominating_barrier(NULL, true, false);
 362   if (dominating_barrier != NULL) {
 363     assert(dominating_barrier->in(Oop) == in(Oop), "");
 364     return dominating_barrier;
 365   }
 366 
 367   return this;
 368 }
 369 
 370 Node *LoadBarrierNode::Ideal(PhaseGVN *phase, bool can_reshape) {
 371   if (remove_dead_region(phase, can_reshape)) {
 372     return this;
 373   }
 374 
 375   Node* val = in(Oop);
 376   Node* mem = in(Memory);
 377   Node* ctrl = in(Control);
 378   Node* adr = in(Address);
 379   assert(val->Opcode() != Op_LoadN, "");
 380 
 381   if (mem->is_MergeMem()) {
 382     Node* new_mem = mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw);
 383     set_req(Memory, new_mem);
 384     if (mem->outcnt() == 0 && can_reshape) {
 385       phase->is_IterGVN()->_worklist.push(mem);
 386     }
 387 
 388     return this;
 389   }
 390 
 391   bool optimizeLoadBarriers = phase->C->directive()->ZOptimizeLoadBarriersOption;
 392   LoadBarrierNode* dominating_barrier = optimizeLoadBarriers ? has_dominating_barrier(NULL, !can_reshape, !phase->C->major_progress()) : NULL;
 393   if (dominating_barrier != NULL && dominating_barrier->in(Oop) != in(Oop)) {
 394     assert(in(Address) == dominating_barrier->in(Address), "");
 395     set_req(Similar, dominating_barrier->proj_out(Oop));
 396     return this;
 397   }
 398 
 399   bool eliminate = (optimizeLoadBarriers && !(val->is_Phi() || val->Opcode() == Op_LoadP || val->Opcode() == Op_GetAndSetP || val->is_DecodeN())) ||
 400                    (can_reshape && (dominating_barrier != NULL || !has_true_uses()));
 401 
 402   if (eliminate) {
 403     if (can_reshape) {
 404       PhaseIterGVN* igvn = phase->is_IterGVN();
 405       Node* out_ctrl = proj_out_or_null(Control);
 406       Node* out_res = proj_out_or_null(Oop);
 407 
 408       if (out_ctrl != NULL) {
 409         igvn->replace_node(out_ctrl, ctrl);
 410       }
 411 
 412       // That transformation may cause the Similar edge on the load barrier to be invalid
 413       fix_similar_in_uses(igvn);
 414       if (out_res != NULL) {
 415         if (dominating_barrier != NULL) {
 416           igvn->replace_node(out_res, dominating_barrier->proj_out(Oop));
 417         } else {
 418           igvn->replace_node(out_res, val);
 419         }
 420       }
 421     }
 422 
 423     return new ConINode(TypeInt::ZERO);
 424   }
 425 
 426   // If the Similar edge is no longer a load barrier, clear it
 427   Node* similar = in(Similar);
 428   if (!similar->is_top() && !(similar->is_Proj() && similar->in(0)->is_LoadBarrier())) {
 429     set_req(Similar, phase->C->top());
 430     return this;
 431   }
 432 
 433   if (can_reshape) {
 434     // If this barrier is linked through the Similar edge by a
 435     // dominated barrier and both barriers have the same Oop field,
 436     // the dominated barrier can go away, so push it for reprocessing.
 437     // We also want to avoid a barrier to depend on another dominating
 438     // barrier through its Similar edge that itself depend on another
 439     // barrier through its Similar edge and rather have the first
 440     // depend on the third.
 441     PhaseIterGVN* igvn = phase->is_IterGVN();
 442     Node* out_res = proj_out(Oop);
 443     for (DUIterator_Fast imax, i = out_res->fast_outs(imax); i < imax; i++) {
 444       Node* u = out_res->fast_out(i);
 445       if (u->is_LoadBarrier() && u->in(Similar) == out_res &&
 446           (u->in(Oop) == val || !u->in(Similar)->is_top())) {
 447         igvn->_worklist.push(u);
 448       }
 449     }
 450 
 451     push_dominated_barriers(igvn);
 452   }
 453 
 454   return NULL;
 455 }
 456 
 457 uint LoadBarrierNode::match_edge(uint idx) const {
 458   ShouldNotReachHere();
 459   return 0;
 460 }
 461 
 462 void LoadBarrierNode::fix_similar_in_uses(PhaseIterGVN* igvn) {
 463   Node* out_res = proj_out_or_null(Oop);
 464   if (out_res == NULL) {
 465     return;
 466   }
 467 
 468   for (DUIterator_Fast imax, i = out_res->fast_outs(imax); i < imax; i++) {
 469     Node* u = out_res->fast_out(i);
 470     if (u->is_LoadBarrier() && u->in(Similar) == out_res) {
 471       igvn->replace_input_of(u, Similar, igvn->C->top());
 472       --i;
 473       --imax;
 474     }
 475   }
 476 }
 477 
 478 bool LoadBarrierNode::has_true_uses() const {
 479   Node* out_res = proj_out_or_null(Oop);
 480   if (out_res == NULL) {
 481     return false;
 482   }
 483 
 484   for (DUIterator_Fast imax, i = out_res->fast_outs(imax); i < imax; i++) {
 485     Node* u = out_res->fast_out(i);
 486     if (!u->is_LoadBarrier() || u->in(Similar) != out_res) {
 487       return true;
 488     }
 489   }
 490 
 491   return false;
 492 }
 493 
 494 // == Accesses ==
 495 
 496 Node* ZBarrierSetC2::make_cas_loadbarrier(C2AtomicAccess& access) const {
 497   assert(!UseCompressedOops, "Not allowed");
 498   CompareAndSwapNode* cas = (CompareAndSwapNode*)access.raw_access();
 499   PhaseGVN& gvn = access.kit()->gvn();
 500   Compile* C = Compile::current();
 501   GraphKit* kit = access.kit();
 502 
 503   Node* in_ctrl     = cas->in(MemNode::Control);
 504   Node* in_mem      = cas->in(MemNode::Memory);
 505   Node* in_adr      = cas->in(MemNode::Address);
 506   Node* in_val      = cas->in(MemNode::ValueIn);
 507   Node* in_expected = cas->in(LoadStoreConditionalNode::ExpectedIn);
 508 
 509   float likely                   = PROB_LIKELY(0.999);
 510 
 511   const TypePtr *adr_type        = gvn.type(in_adr)->isa_ptr();
 512   Compile::AliasType* alias_type = C->alias_type(adr_type);
 513   int alias_idx                  = C->get_alias_index(adr_type);
 514 
 515   // Outer check - true: continue, false: load and check
 516   Node* region   = new RegionNode(3);
 517   Node* phi      = new PhiNode(region, TypeInt::BOOL);
 518   Node* phi_mem  = new PhiNode(region, Type::MEMORY, adr_type);
 519 
 520   // Inner check - is the healed ref equal to the expected
 521   Node* region2  = new RegionNode(3);
 522   Node* phi2     = new PhiNode(region2, TypeInt::BOOL);
 523   Node* phi_mem2 = new PhiNode(region2, Type::MEMORY, adr_type);
 524 
 525   // CAS node returns 0 or 1
 526   Node* cmp     = gvn.transform(new CmpINode(cas, kit->intcon(0)));
 527   Node* bol     = gvn.transform(new BoolNode(cmp, BoolTest::ne))->as_Bool();
 528   IfNode* iff   = gvn.transform(new IfNode(in_ctrl, bol, likely, COUNT_UNKNOWN))->as_If();
 529   Node* then    = gvn.transform(new IfTrueNode(iff));
 530   Node* elsen   = gvn.transform(new IfFalseNode(iff));
 531 
 532   Node* scmemproj1   = gvn.transform(new SCMemProjNode(cas));
 533 
 534   kit->set_memory(scmemproj1, alias_idx);
 535   phi_mem->init_req(1, scmemproj1);
 536   phi_mem2->init_req(2, scmemproj1);
 537 
 538   // CAS fail - reload and heal oop
 539   Node* reload      = kit->make_load(elsen, in_adr, TypeOopPtr::BOTTOM, T_OBJECT, MemNode::unordered);
 540   Node* barrier     = gvn.transform(new LoadBarrierNode(C, elsen, scmemproj1, reload, in_adr, false, true, false));
 541   Node* barrierctrl = gvn.transform(new ProjNode(barrier, LoadBarrierNode::Control));
 542   Node* barrierdata = gvn.transform(new ProjNode(barrier, LoadBarrierNode::Oop));
 543 
 544   // Check load
 545   Node* tmpX    = gvn.transform(new CastP2XNode(NULL, barrierdata));
 546   Node* in_expX = gvn.transform(new CastP2XNode(NULL, in_expected));
 547   Node* cmp2    = gvn.transform(new CmpXNode(tmpX, in_expX));
 548   Node *bol2    = gvn.transform(new BoolNode(cmp2, BoolTest::ne))->as_Bool();
 549   IfNode* iff2  = gvn.transform(new IfNode(barrierctrl, bol2, likely, COUNT_UNKNOWN))->as_If();
 550   Node* then2   = gvn.transform(new IfTrueNode(iff2));
 551   Node* elsen2  = gvn.transform(new IfFalseNode(iff2));
 552 
 553   // redo CAS
 554   Node* cas2       = gvn.transform(new CompareAndSwapPNode(elsen2, kit->memory(alias_idx), in_adr, in_val, in_expected, cas->order()));
 555   Node* scmemproj2 = gvn.transform(new SCMemProjNode(cas2));
 556   kit->set_control(elsen2);
 557   kit->set_memory(scmemproj2, alias_idx);
 558 
 559   // Merge inner flow - check if healed oop was equal too expected.
 560   region2->set_req(1, kit->control());
 561   region2->set_req(2, then2);
 562   phi2->set_req(1, cas2);
 563   phi2->set_req(2, kit->intcon(0));
 564   phi_mem2->init_req(1, scmemproj2);
 565   kit->set_memory(phi_mem2, alias_idx);
 566 
 567   // Merge outer flow - then check if first CAS succeeded
 568   region->set_req(1, then);
 569   region->set_req(2, region2);
 570   phi->set_req(1, kit->intcon(1));
 571   phi->set_req(2, phi2);
 572   phi_mem->init_req(2, phi_mem2);
 573   kit->set_memory(phi_mem, alias_idx);
 574 
 575   gvn.transform(region2);
 576   gvn.transform(phi2);
 577   gvn.transform(phi_mem2);
 578   gvn.transform(region);
 579   gvn.transform(phi);
 580   gvn.transform(phi_mem);
 581 
 582   kit->set_control(region);
 583   kit->insert_mem_bar(Op_MemBarCPUOrder);
 584 
 585   return phi;
 586 }
 587 
 588 Node* ZBarrierSetC2::make_cmpx_loadbarrier(C2AtomicAccess& access) const {
 589   CompareAndExchangePNode* cmpx = (CompareAndExchangePNode*)access.raw_access();
 590   GraphKit* kit = access.kit();
 591   PhaseGVN& gvn = kit->gvn();
 592   Compile* C = Compile::current();
 593 
 594   Node* in_ctrl     = cmpx->in(MemNode::Control);
 595   Node* in_mem      = cmpx->in(MemNode::Memory);
 596   Node* in_adr      = cmpx->in(MemNode::Address);
 597   Node* in_val      = cmpx->in(MemNode::ValueIn);
 598   Node* in_expected = cmpx->in(LoadStoreConditionalNode::ExpectedIn);
 599 
 600   float likely                   = PROB_LIKELY(0.999);
 601 
 602   const TypePtr *adr_type        = cmpx->get_ptr_type();
 603   Compile::AliasType* alias_type = C->alias_type(adr_type);
 604   int alias_idx                  = C->get_alias_index(adr_type);
 605 
 606   // Outer check - true: continue, false: load and check
 607   Node* region  = new RegionNode(3);
 608   Node* phi     = new PhiNode(region, adr_type);
 609 
 610   // Inner check - is the healed ref equal to the expected
 611   Node* region2 = new RegionNode(3);
 612   Node* phi2    = new PhiNode(region2, adr_type);
 613 
 614   // Check if cmpx succeeded
 615   Node* cmp     = gvn.transform(new CmpPNode(cmpx, in_expected));
 616   Node* bol     = gvn.transform(new BoolNode(cmp, BoolTest::eq))->as_Bool();
 617   IfNode* iff   = gvn.transform(new IfNode(in_ctrl, bol, likely, COUNT_UNKNOWN))->as_If();
 618   Node* then    = gvn.transform(new IfTrueNode(iff));
 619   Node* elsen   = gvn.transform(new IfFalseNode(iff));
 620 
 621   Node* scmemproj1  = gvn.transform(new SCMemProjNode(cmpx));
 622   kit->set_memory(scmemproj1, alias_idx);
 623 
 624   // CAS fail - reload and heal oop
 625   Node* reload      = kit->make_load(elsen, in_adr, TypeOopPtr::BOTTOM, T_OBJECT, MemNode::unordered);
 626   Node* barrier     = gvn.transform(new LoadBarrierNode(C, elsen, scmemproj1, reload, in_adr, false, true, false));
 627   Node* barrierctrl = gvn.transform(new ProjNode(barrier, LoadBarrierNode::Control));
 628   Node* barrierdata = gvn.transform(new ProjNode(barrier, LoadBarrierNode::Oop));
 629 
 630   // Check load
 631   Node* tmpX    = gvn.transform(new CastP2XNode(NULL, barrierdata));
 632   Node* in_expX = gvn.transform(new CastP2XNode(NULL, in_expected));
 633   Node* cmp2    = gvn.transform(new CmpXNode(tmpX, in_expX));
 634   Node *bol2    = gvn.transform(new BoolNode(cmp2, BoolTest::ne))->as_Bool();
 635   IfNode* iff2  = gvn.transform(new IfNode(barrierctrl, bol2, likely, COUNT_UNKNOWN))->as_If();
 636   Node* then2   = gvn.transform(new IfTrueNode(iff2));
 637   Node* elsen2  = gvn.transform(new IfFalseNode(iff2));
 638 
 639   // Redo CAS
 640   Node* cmpx2      = gvn.transform(new CompareAndExchangePNode(elsen2, kit->memory(alias_idx), in_adr, in_val, in_expected, adr_type, cmpx->get_ptr_type(), cmpx->order()));
 641   Node* scmemproj2 = gvn.transform(new SCMemProjNode(cmpx2));
 642   kit->set_control(elsen2);
 643   kit->set_memory(scmemproj2, alias_idx);
 644 
 645   // Merge inner flow - check if healed oop was equal too expected.
 646   region2->set_req(1, kit->control());
 647   region2->set_req(2, then2);
 648   phi2->set_req(1, cmpx2);
 649   phi2->set_req(2, barrierdata);
 650 
 651   // Merge outer flow - then check if first cas succeeded
 652   region->set_req(1, then);
 653   region->set_req(2, region2);
 654   phi->set_req(1, cmpx);
 655   phi->set_req(2, phi2);
 656 
 657   gvn.transform(region2);
 658   gvn.transform(phi2);
 659   gvn.transform(region);
 660   gvn.transform(phi);
 661 
 662   kit->set_control(region);
 663   kit->set_memory(in_mem, alias_idx);
 664   kit->insert_mem_bar(Op_MemBarCPUOrder);
 665 
 666   return phi;
 667 }
 668 
 669 Node* ZBarrierSetC2::load_barrier(GraphKit* kit, Node* val, Node* adr, bool weak, bool writeback, bool oop_reload_allowed) const {
 670   PhaseGVN& gvn = kit->gvn();
 671   Node* barrier = new LoadBarrierNode(Compile::current(), kit->control(), kit->memory(TypeRawPtr::BOTTOM), val, adr, weak, writeback, oop_reload_allowed);
 672   Node* transformed_barrier = gvn.transform(barrier);
 673 
 674   if (transformed_barrier->is_LoadBarrier()) {
 675     if (barrier == transformed_barrier) {
 676       kit->set_control(gvn.transform(new ProjNode(barrier, LoadBarrierNode::Control)));
 677     }
 678     Node* result = gvn.transform(new ProjNode(transformed_barrier, LoadBarrierNode::Oop));
 679     assert(is_gc_barrier_node(result), "sanity");
 680     assert(step_over_gc_barrier(result) == val, "sanity");
 681     return result;
 682   } else {
 683     return val;
 684   }
 685 }
 686 
 687 static bool barrier_needed(C2Access access) {
 688   return ZBarrierSet::barrier_needed(access.decorators(), access.type());
 689 }
 690 
 691 Node* ZBarrierSetC2::load_at_resolved(C2Access& access, const Type* val_type) const {
 692   Node* p = BarrierSetC2::load_at_resolved(access, val_type);
 693   if (!barrier_needed(access)) {
 694     return p;
 695   }
 696 
 697   bool weak = (access.decorators() & ON_WEAK_OOP_REF) != 0;
 698 
 699   GraphKit* kit = access.kit();
 700   PhaseGVN& gvn = kit->gvn();
 701   Node* adr = access.addr().node();
 702   Node* heap_base_oop = access.base();
 703   bool unsafe = (access.decorators() & C2_UNSAFE_ACCESS) != 0;
 704   if (unsafe) {
 705     if (!ZVerifyLoadBarriers) {
 706       p = load_barrier(kit, p, adr);
 707     } else {
 708       if (!TypePtr::NULL_PTR->higher_equal(gvn.type(heap_base_oop))) {
 709         p = load_barrier(kit, p, adr);
 710       } else {
 711         IdealKit ideal(kit);
 712         IdealVariable res(ideal);
 713 #define __ ideal.
 714         __ declarations_done();
 715         __ set(res, p);
 716         __ if_then(heap_base_oop, BoolTest::ne, kit->null(), PROB_UNLIKELY(0.999)); {
 717           kit->sync_kit(ideal);
 718           p = load_barrier(kit, p, adr);
 719           __ set(res, p);
 720           __ sync_kit(kit);
 721         } __ end_if();
 722         kit->final_sync(ideal);
 723         p = __ value(res);
 724 #undef __
 725       }
 726     }
 727     return p;
 728   } else {
 729     return load_barrier(access.kit(), p, access.addr().node(), weak, true, true);
 730   }
 731 }
 732 
 733 Node* ZBarrierSetC2::atomic_cmpxchg_val_at_resolved(C2AtomicAccess& access, Node* expected_val,
 734                                                     Node* new_val, const Type* val_type) const {
 735   Node* result = BarrierSetC2::atomic_cmpxchg_val_at_resolved(access, expected_val, new_val, val_type);
 736   if (!barrier_needed(access)) {
 737     return result;
 738   }
 739 
 740   access.set_needs_pinning(false);
 741   return make_cmpx_loadbarrier(access);
 742 }
 743 
 744 Node* ZBarrierSetC2::atomic_cmpxchg_bool_at_resolved(C2AtomicAccess& access, Node* expected_val,
 745                                                      Node* new_val, const Type* value_type) const {
 746   Node* result = BarrierSetC2::atomic_cmpxchg_bool_at_resolved(access, expected_val, new_val, value_type);
 747   if (!barrier_needed(access)) {
 748     return result;
 749   }
 750 
 751   Node* load_store = access.raw_access();
 752   bool weak_cas = (access.decorators() & C2_WEAK_CMPXCHG) != 0;
 753   bool expected_is_null = (expected_val->get_ptr_type() == TypePtr::NULL_PTR);
 754 
 755   if (!expected_is_null) {
 756     if (weak_cas) {
 757       access.set_needs_pinning(false);
 758       load_store = make_cas_loadbarrier(access);
 759     } else {
 760       access.set_needs_pinning(false);
 761       load_store = make_cas_loadbarrier(access);
 762     }
 763   }
 764 
 765   return load_store;
 766 }
 767 
 768 Node* ZBarrierSetC2::atomic_xchg_at_resolved(C2AtomicAccess& access, Node* new_val, const Type* val_type) const {
 769   Node* result = BarrierSetC2::atomic_xchg_at_resolved(access, new_val, val_type);
 770   if (!barrier_needed(access)) {
 771     return result;
 772   }
 773 
 774   Node* load_store = access.raw_access();
 775   Node* adr = access.addr().node();
 776 
 777   return load_barrier(access.kit(), load_store, adr, false, false, false);
 778 }
 779 
 780 // == Macro Expansion ==
 781 
 782 void ZBarrierSetC2::expand_loadbarrier_node(PhaseMacroExpand* phase, LoadBarrierNode* barrier) const {
 783   Node* in_ctrl = barrier->in(LoadBarrierNode::Control);
 784   Node* in_mem  = barrier->in(LoadBarrierNode::Memory);
 785   Node* in_val  = barrier->in(LoadBarrierNode::Oop);
 786   Node* in_adr  = barrier->in(LoadBarrierNode::Address);
 787 
 788   Node* out_ctrl = barrier->proj_out(LoadBarrierNode::Control);
 789   Node* out_res  = barrier->proj_out(LoadBarrierNode::Oop);
 790 
 791   PhaseIterGVN &igvn = phase->igvn();
 792 
 793   if (ZVerifyLoadBarriers) {
 794     igvn.replace_node(out_res, in_val);
 795     igvn.replace_node(out_ctrl, in_ctrl);
 796     return;
 797   }
 798 
 799   if (barrier->can_be_eliminated()) {
 800     // Clone and pin the load for this barrier below the dominating
 801     // barrier: the load cannot be allowed to float above the
 802     // dominating barrier
 803     Node* load = in_val;
 804 
 805     if (load->is_Load()) {
 806       Node* new_load = load->clone();
 807       Node* addp = new_load->in(MemNode::Address);
 808       assert(addp->is_AddP() || addp->is_Phi() || addp->is_Load(), "bad address");
 809       Node* cast = new CastPPNode(addp, igvn.type(addp), true);
 810       Node* ctrl = NULL;
 811       Node* similar = barrier->in(LoadBarrierNode::Similar);
 812       if (similar->is_Phi()) {
 813         // already expanded
 814         ctrl = similar->in(0);
 815       } else {
 816         assert(similar->is_Proj() && similar->in(0)->is_LoadBarrier(), "unexpected graph shape");
 817         ctrl = similar->in(0)->as_LoadBarrier()->proj_out(LoadBarrierNode::Control);
 818       }
 819       assert(ctrl != NULL, "bad control");
 820       cast->set_req(0, ctrl);
 821       igvn.transform(cast);
 822       new_load->set_req(MemNode::Address, cast);
 823       igvn.transform(new_load);
 824 
 825       igvn.replace_node(out_res, new_load);
 826       igvn.replace_node(out_ctrl, in_ctrl);
 827       return;
 828     }
 829     // cannot eliminate
 830   }
 831 
 832   // There are two cases that require the basic loadbarrier
 833   // 1) When the writeback of a healed oop must be avoided (swap)
 834   // 2) When we must guarantee that no reload of is done (swap, cas, cmpx)
 835   if (!barrier->is_writeback()) {
 836     assert(!barrier->oop_reload_allowed(), "writeback barriers should be marked as requires oop");
 837   }
 838 
 839   if (!barrier->oop_reload_allowed()) {
 840     expand_loadbarrier_basic(phase, barrier);
 841   } else {
 842     expand_loadbarrier_optimized(phase, barrier);
 843   }
 844 }
 845 
 846 // Basic loadbarrier using conventional argument passing
 847 void ZBarrierSetC2::expand_loadbarrier_basic(PhaseMacroExpand* phase, LoadBarrierNode *barrier) const {
 848   PhaseIterGVN &igvn = phase->igvn();
 849 
 850   Node* in_ctrl = barrier->in(LoadBarrierNode::Control);
 851   Node* in_mem  = barrier->in(LoadBarrierNode::Memory);
 852   Node* in_val  = barrier->in(LoadBarrierNode::Oop);
 853   Node* in_adr  = barrier->in(LoadBarrierNode::Address);
 854 
 855   Node* out_ctrl = barrier->proj_out(LoadBarrierNode::Control);
 856   Node* out_res  = barrier->proj_out(LoadBarrierNode::Oop);
 857 
 858   float unlikely  = PROB_UNLIKELY(0.999);
 859   const Type* in_val_maybe_null_t = igvn.type(in_val);
 860 
 861   Node* jthread = igvn.transform(new ThreadLocalNode());
 862   Node* adr = phase->basic_plus_adr(jthread, in_bytes(ZThreadLocalData::address_bad_mask_offset()));
 863   Node* bad_mask = igvn.transform(LoadNode::make(igvn, in_ctrl, in_mem, adr, TypeRawPtr::BOTTOM, TypeX_X, TypeX_X->basic_type(), MemNode::unordered));
 864   Node* cast = igvn.transform(new CastP2XNode(in_ctrl, in_val));
 865   Node* obj_masked = igvn.transform(new AndXNode(cast, bad_mask));
 866   Node* cmp = igvn.transform(new CmpXNode(obj_masked, igvn.zerocon(TypeX_X->basic_type())));
 867   Node *bol = igvn.transform(new BoolNode(cmp, BoolTest::ne))->as_Bool();
 868   IfNode* iff = igvn.transform(new IfNode(in_ctrl, bol, unlikely, COUNT_UNKNOWN))->as_If();
 869   Node* then = igvn.transform(new IfTrueNode(iff));
 870   Node* elsen = igvn.transform(new IfFalseNode(iff));
 871 
 872   Node* result_region;
 873   Node* result_val;
 874 
 875   result_region = new RegionNode(3);
 876   result_val = new PhiNode(result_region, TypeInstPtr::BOTTOM);
 877 
 878   result_region->set_req(1, elsen);
 879   Node* res = igvn.transform(new CastPPNode(in_val, in_val_maybe_null_t));
 880   res->init_req(0, elsen);
 881   result_val->set_req(1, res);
 882 
 883   const TypeFunc *tf = load_barrier_Type();
 884   Node* call;
 885   if (barrier->is_weak()) {
 886     call = new CallLeafNode(tf,
 887                             ZBarrierSetRuntime::load_barrier_on_weak_oop_field_preloaded_addr(),
 888                             "ZBarrierSetRuntime::load_barrier_on_weak_oop_field_preloaded",
 889                             TypeRawPtr::BOTTOM);
 890   } else {
 891     call = new CallLeafNode(tf,
 892                             ZBarrierSetRuntime::load_barrier_on_oop_field_preloaded_addr(),
 893                             "ZBarrierSetRuntime::load_barrier_on_oop_field_preloaded",
 894                             TypeRawPtr::BOTTOM);
 895   }
 896 
 897   call->init_req(TypeFunc::Control, then);
 898   call->init_req(TypeFunc::I_O    , phase->top());
 899   call->init_req(TypeFunc::Memory , in_mem);
 900   call->init_req(TypeFunc::FramePtr, phase->top());
 901   call->init_req(TypeFunc::ReturnAdr, phase->top());
 902   call->init_req(TypeFunc::Parms+0, in_val);
 903   if (barrier->is_writeback()) {
 904     call->init_req(TypeFunc::Parms+1, in_adr);
 905   } else {
 906     // When slow path is called with a null address, the healed oop will not be written back
 907     call->init_req(TypeFunc::Parms+1, igvn.zerocon(T_OBJECT));
 908   }
 909   call = igvn.transform(call);
 910 
 911   Node* ctrl = igvn.transform(new ProjNode(call, TypeFunc::Control));
 912   res = igvn.transform(new ProjNode(call, TypeFunc::Parms));
 913   res = igvn.transform(new CheckCastPPNode(ctrl, res, in_val_maybe_null_t));
 914 
 915   result_region->set_req(2, ctrl);
 916   result_val->set_req(2, res);
 917 
 918   result_region = igvn.transform(result_region);
 919   result_val = igvn.transform(result_val);
 920 
 921   if (out_ctrl != NULL) { // Added if cond
 922     igvn.replace_node(out_ctrl, result_region);
 923   }
 924   igvn.replace_node(out_res, result_val);
 925 }
 926 
 927 // Optimized, low spill, loadbarrier variant using stub specialized on register used
 928 void ZBarrierSetC2::expand_loadbarrier_optimized(PhaseMacroExpand* phase, LoadBarrierNode *barrier) const {
 929   PhaseIterGVN &igvn = phase->igvn();
 930 #ifdef PRINT_NODE_TRAVERSALS
 931   Node* preceding_barrier_node = barrier->in(LoadBarrierNode::Oop);
 932 #endif
 933 
 934   Node* in_ctrl = barrier->in(LoadBarrierNode::Control);
 935   Node* in_mem = barrier->in(LoadBarrierNode::Memory);
 936   Node* in_val = barrier->in(LoadBarrierNode::Oop);
 937   Node* in_adr = barrier->in(LoadBarrierNode::Address);
 938 
 939   Node* out_ctrl = barrier->proj_out(LoadBarrierNode::Control);
 940   Node* out_res = barrier->proj_out(LoadBarrierNode::Oop);
 941 
 942   assert(barrier->in(LoadBarrierNode::Oop) != NULL, "oop to loadbarrier node cannot be null");
 943 
 944 #ifdef PRINT_NODE_TRAVERSALS
 945   tty->print("\n\n\nBefore barrier optimization:\n");
 946   traverse(barrier, out_ctrl, out_res, -1);
 947 
 948   tty->print("\nBefore barrier optimization:  preceding_barrier_node\n");
 949   traverse(preceding_barrier_node, out_ctrl, out_res, -1);
 950 #endif
 951 
 952   float unlikely  = PROB_UNLIKELY(0.999);
 953 
 954   Node* jthread = igvn.transform(new ThreadLocalNode());
 955   Node* adr = phase->basic_plus_adr(jthread, in_bytes(ZThreadLocalData::address_bad_mask_offset()));
 956   Node* bad_mask = igvn.transform(LoadNode::make(igvn, in_ctrl, in_mem, adr,
 957                                                  TypeRawPtr::BOTTOM, TypeX_X, TypeX_X->basic_type(),
 958                                                  MemNode::unordered));
 959   Node* cast = igvn.transform(new CastP2XNode(in_ctrl, in_val));
 960   Node* obj_masked = igvn.transform(new AndXNode(cast, bad_mask));
 961   Node* cmp = igvn.transform(new CmpXNode(obj_masked, igvn.zerocon(TypeX_X->basic_type())));
 962   Node *bol = igvn.transform(new BoolNode(cmp, BoolTest::ne))->as_Bool();
 963   IfNode* iff = igvn.transform(new IfNode(in_ctrl, bol, unlikely, COUNT_UNKNOWN))->as_If();
 964   Node* then = igvn.transform(new IfTrueNode(iff));
 965   Node* elsen = igvn.transform(new IfFalseNode(iff));
 966 
 967   Node* slow_path_surrogate;
 968   if (!barrier->is_weak()) {
 969     slow_path_surrogate = igvn.transform(new LoadBarrierSlowRegNode(then, in_mem, in_adr, in_val->adr_type(),
 970                                                                     (const TypePtr*) in_val->bottom_type(), MemNode::unordered));
 971   } else {
 972     slow_path_surrogate = igvn.transform(new LoadBarrierWeakSlowRegNode(then, in_mem, in_adr, in_val->adr_type(),
 973                                                                         (const TypePtr*) in_val->bottom_type(), MemNode::unordered));
 974   }
 975 
 976   Node *new_loadp;
 977   new_loadp = slow_path_surrogate;
 978   // Create the final region/phi pair to converge cntl/data paths to downstream code
 979   Node* result_region = igvn.transform(new RegionNode(3));
 980   result_region->set_req(1, then);
 981   result_region->set_req(2, elsen);
 982 
 983   Node* result_phi = igvn.transform(new PhiNode(result_region, TypeInstPtr::BOTTOM));
 984   result_phi->set_req(1, new_loadp);
 985   result_phi->set_req(2, barrier->in(LoadBarrierNode::Oop));
 986 
 987   // Finally, connect the original outputs to the barrier region and phi to complete the expansion/substitution
 988   // igvn.replace_node(out_ctrl, result_region);
 989   if (out_ctrl != NULL) { // added if cond
 990     igvn.replace_node(out_ctrl, result_region);
 991   }
 992   igvn.replace_node(out_res, result_phi);
 993 
 994   assert(barrier->outcnt() == 0,"LoadBarrier macro node has non-null outputs after expansion!");
 995 
 996 #ifdef PRINT_NODE_TRAVERSALS
 997   tty->print("\nAfter barrier optimization:  old out_ctrl\n");
 998   traverse(out_ctrl, out_ctrl, out_res, -1);
 999   tty->print("\nAfter barrier optimization:  old out_res\n");
1000   traverse(out_res, out_ctrl, out_res, -1);
1001   tty->print("\nAfter barrier optimization:  old barrier\n");
1002   traverse(barrier, out_ctrl, out_res, -1);
1003   tty->print("\nAfter barrier optimization:  preceding_barrier_node\n");
1004   traverse(preceding_barrier_node, result_region, result_phi, -1);
1005 #endif
1006 
1007   assert(is_gc_barrier_node(result_phi), "sanity");
1008   assert(step_over_gc_barrier(result_phi) == in_val, "sanity");
1009 
1010   return;
1011 }
1012 
1013 bool ZBarrierSetC2::expand_macro_nodes(PhaseMacroExpand* macro) const {
1014   Compile* C = Compile::current();
1015   PhaseIterGVN &igvn = macro->igvn();
1016   ZBarrierSetC2State* s = state();
1017   if (s->load_barrier_count() > 0) {
1018 #ifdef ASSERT
1019     verify_gc_barriers(false);
1020 #endif
1021     igvn.set_delay_transform(true);
1022     int skipped = 0;
1023     while (s->load_barrier_count() > skipped) {
1024       int load_barrier_count = s->load_barrier_count();
1025       LoadBarrierNode * n = s->load_barrier_node(load_barrier_count-1-skipped);
1026       if (igvn.type(n) == Type::TOP || (n->in(0) != NULL && n->in(0)->is_top())) {
1027         // Node is unreachable, so don't try to expand it
1028         s->remove_load_barrier_node(n);
1029         continue;
1030       }
1031       if (!n->can_be_eliminated()) {
1032         skipped++;
1033         continue;
1034       }
1035       expand_loadbarrier_node(macro, n);
1036       assert(s->load_barrier_count() < load_barrier_count, "must have deleted a node from load barrier list");
1037       if (C->failing())  return true;
1038     }
1039     while (s->load_barrier_count() > 0) {
1040       int load_barrier_count = s->load_barrier_count();
1041       LoadBarrierNode* n = s->load_barrier_node(load_barrier_count - 1);
1042       assert(!(igvn.type(n) == Type::TOP || (n->in(0) != NULL && n->in(0)->is_top())), "should have been processed already");
1043       assert(!n->can_be_eliminated(), "should have been processed already");
1044       expand_loadbarrier_node(macro, n);
1045       assert(s->load_barrier_count() < load_barrier_count, "must have deleted a node from load barrier list");
1046       if (C->failing())  return true;
1047     }
1048     igvn.set_delay_transform(false);
1049     igvn.optimize();
1050     if (C->failing())  return true;
1051   }
1052   return false;
1053 }
1054 
1055 // == Loop optimization ==
1056 
1057 static bool replace_with_dominating_barrier(PhaseIdealLoop* phase, LoadBarrierNode* lb, bool last_round) {
1058   PhaseIterGVN &igvn = phase->igvn();
1059   Compile* C = Compile::current();
1060 
1061   LoadBarrierNode* lb2 = lb->has_dominating_barrier(phase, false, last_round);
1062   if (lb2 != NULL) {
1063     if (lb->in(LoadBarrierNode::Oop) != lb2->in(LoadBarrierNode::Oop)) {
1064       assert(lb->in(LoadBarrierNode::Address) == lb2->in(LoadBarrierNode::Address), "");
1065       igvn.replace_input_of(lb, LoadBarrierNode::Similar, lb2->proj_out(LoadBarrierNode::Oop));
1066       C->set_major_progress();
1067     } else  {
1068       // That transformation may cause the Similar edge on dominated load barriers to be invalid
1069       lb->fix_similar_in_uses(&igvn);
1070 
1071       Node* val = lb->proj_out(LoadBarrierNode::Oop);
1072       assert(lb2->has_true_uses(), "");
1073       assert(lb2->in(LoadBarrierNode::Oop) == lb->in(LoadBarrierNode::Oop), "");
1074 
1075       phase->lazy_update(lb, lb->in(LoadBarrierNode::Control));
1076       phase->lazy_replace(lb->proj_out(LoadBarrierNode::Control), lb->in(LoadBarrierNode::Control));
1077       igvn.replace_node(val, lb2->proj_out(LoadBarrierNode::Oop));
1078 
1079       return true;
1080     }
1081   }
1082   return false;
1083 }
1084 
1085 static Node* find_dominating_memory(PhaseIdealLoop* phase, Node* mem, Node* dom, int i) {
1086   assert(dom->is_Region() || i == -1, "");
1087   Node* m = mem;
1088   while(phase->is_dominator(dom, phase->has_ctrl(m) ? phase->get_ctrl(m) : m->in(0))) {
1089     if (m->is_Mem()) {
1090       assert(m->as_Mem()->adr_type() == TypeRawPtr::BOTTOM, "");
1091       m = m->in(MemNode::Memory);
1092     } else if (m->is_MergeMem()) {
1093       m = m->as_MergeMem()->memory_at(Compile::AliasIdxRaw);
1094     } else if (m->is_Phi()) {
1095       if (m->in(0) == dom && i != -1) {
1096         m = m->in(i);
1097         break;
1098       } else {
1099         m = m->in(LoopNode::EntryControl);
1100       }
1101     } else if (m->is_Proj()) {
1102       m = m->in(0);
1103     } else if (m->is_SafePoint() || m->is_MemBar()) {
1104       m = m->in(TypeFunc::Memory);
1105     } else {
1106 #ifdef ASSERT
1107       m->dump();
1108 #endif
1109       ShouldNotReachHere();
1110     }
1111   }
1112   return m;
1113 }
1114 
1115 static LoadBarrierNode* clone_load_barrier(PhaseIdealLoop* phase, LoadBarrierNode* lb, Node* ctl, Node* mem, Node* oop_in) {
1116   PhaseIterGVN &igvn = phase->igvn();
1117   Compile* C = Compile::current();
1118   Node* the_clone = lb->clone();
1119   the_clone->set_req(LoadBarrierNode::Control, ctl);
1120   the_clone->set_req(LoadBarrierNode::Memory, mem);
1121   if (oop_in != NULL) {
1122     the_clone->set_req(LoadBarrierNode::Oop, oop_in);
1123   }
1124 
1125   LoadBarrierNode* new_lb = the_clone->as_LoadBarrier();
1126   igvn.register_new_node_with_optimizer(new_lb);
1127   IdealLoopTree *loop = phase->get_loop(new_lb->in(0));
1128   phase->set_ctrl(new_lb, new_lb->in(0));
1129   phase->set_loop(new_lb, loop);
1130   phase->set_idom(new_lb, new_lb->in(0), phase->dom_depth(new_lb->in(0))+1);
1131   if (!loop->_child) {
1132     loop->_body.push(new_lb);
1133   }
1134 
1135   Node* proj_ctl = new ProjNode(new_lb, LoadBarrierNode::Control);
1136   igvn.register_new_node_with_optimizer(proj_ctl);
1137   phase->set_ctrl(proj_ctl, proj_ctl->in(0));
1138   phase->set_loop(proj_ctl, loop);
1139   phase->set_idom(proj_ctl, new_lb, phase->dom_depth(new_lb)+1);
1140   if (!loop->_child) {
1141     loop->_body.push(proj_ctl);
1142   }
1143 
1144   Node* proj_oop = new ProjNode(new_lb, LoadBarrierNode::Oop);
1145   phase->register_new_node(proj_oop, new_lb);
1146 
1147   if (!new_lb->in(LoadBarrierNode::Similar)->is_top()) {
1148     LoadBarrierNode* similar = new_lb->in(LoadBarrierNode::Similar)->in(0)->as_LoadBarrier();
1149     if (!phase->is_dominator(similar, ctl)) {
1150       igvn.replace_input_of(new_lb, LoadBarrierNode::Similar, C->top());
1151     }
1152   }
1153 
1154   return new_lb;
1155 }
1156 
1157 static void replace_barrier(PhaseIdealLoop* phase, LoadBarrierNode* lb, Node* new_val) {
1158   PhaseIterGVN &igvn = phase->igvn();
1159   Node* val = lb->proj_out(LoadBarrierNode::Oop);
1160   igvn.replace_node(val, new_val);
1161   phase->lazy_update(lb, lb->in(LoadBarrierNode::Control));
1162   phase->lazy_replace(lb->proj_out(LoadBarrierNode::Control), lb->in(LoadBarrierNode::Control));
1163 }
1164 
1165 static bool split_barrier_thru_phi(PhaseIdealLoop* phase, LoadBarrierNode* lb) {
1166   PhaseIterGVN &igvn = phase->igvn();
1167   Compile* C = Compile::current();
1168 
1169   if (lb->in(LoadBarrierNode::Oop)->is_Phi()) {
1170     Node* oop_phi = lb->in(LoadBarrierNode::Oop);
1171 
1172     if ((oop_phi->req() != 3) || (oop_phi->in(2) == oop_phi)) {
1173       // Ignore phis with only one input
1174       return false;
1175     }
1176 
1177     if (phase->is_dominator(phase->get_ctrl(lb->in(LoadBarrierNode::Address)),
1178                             oop_phi->in(0)) && phase->get_ctrl(lb->in(LoadBarrierNode::Address)) != oop_phi->in(0)) {
1179       // That transformation may cause the Similar edge on dominated load barriers to be invalid
1180       lb->fix_similar_in_uses(&igvn);
1181 
1182       RegionNode* region = oop_phi->in(0)->as_Region();
1183 
1184       int backedge = LoopNode::LoopBackControl;
1185       if (region->is_Loop() && region->in(backedge)->is_Proj() && region->in(backedge)->in(0)->is_If()) {
1186         Node* c = region->in(backedge)->in(0)->in(0);
1187         assert(c->unique_ctrl_out() == region->in(backedge)->in(0), "");
1188         Node* oop = lb->in(LoadBarrierNode::Oop)->in(backedge);
1189         Node* oop_c = phase->has_ctrl(oop) ? phase->get_ctrl(oop) : oop;
1190         if (!phase->is_dominator(oop_c, c)) {
1191           return false;
1192         }
1193       }
1194 
1195       // If the node on the backedge above the phi is the node itself - we have a self loop.
1196       // Don't clone - this will be folded later.
1197       if (oop_phi->in(LoopNode::LoopBackControl) == lb->proj_out(LoadBarrierNode::Oop)) {
1198         return false;
1199       }
1200 
1201       bool is_strip_mined = region->is_CountedLoop() && region->as_CountedLoop()->is_strip_mined();
1202       Node *phi = oop_phi->clone();
1203 
1204       for (uint i = 1; i < region->req(); i++) {
1205         Node* ctrl = region->in(i);
1206         if (ctrl != C->top()) {
1207           assert(!phase->is_dominator(ctrl, region) || region->is_Loop(), "");
1208 
1209           Node* mem = lb->in(LoadBarrierNode::Memory);
1210           Node* m = find_dominating_memory(phase, mem, region, i);
1211 
1212           if (region->is_Loop() && i == LoopNode::LoopBackControl && ctrl->is_Proj() && ctrl->in(0)->is_If()) {
1213             ctrl = ctrl->in(0)->in(0);
1214           } else if (region->is_Loop() && is_strip_mined) {
1215             // If this is a strip mined loop, control must move above OuterStripMinedLoop
1216             assert(i == LoopNode::EntryControl, "check");
1217             assert(ctrl->is_OuterStripMinedLoop(), "sanity");
1218             ctrl = ctrl->as_OuterStripMinedLoop()->in(LoopNode::EntryControl);
1219           }
1220 
1221           LoadBarrierNode* new_lb = clone_load_barrier(phase, lb, ctrl, m, lb->in(LoadBarrierNode::Oop)->in(i));
1222           Node* out_ctrl = new_lb->proj_out(LoadBarrierNode::Control);
1223 
1224           if (is_strip_mined && (i == LoopNode::EntryControl)) {
1225             assert(region->in(i)->is_OuterStripMinedLoop(), "");
1226             igvn.replace_input_of(region->in(i), i, out_ctrl);
1227             phase->set_idom(region->in(i), out_ctrl, phase->dom_depth(out_ctrl));
1228           } else if (ctrl == region->in(i)) {
1229             igvn.replace_input_of(region, i, out_ctrl);
1230             // Only update the idom if is the loop entry we are updating
1231             // - A loop backedge doesn't change the idom
1232             if (region->is_Loop() && i == LoopNode::EntryControl) {
1233               phase->set_idom(region, out_ctrl, phase->dom_depth(out_ctrl));
1234             }
1235           } else {
1236             Node* iff = region->in(i)->in(0);
1237             igvn.replace_input_of(iff, 0, out_ctrl);
1238             phase->set_idom(iff, out_ctrl, phase->dom_depth(out_ctrl)+1);
1239           }
1240           phi->set_req(i, new_lb->proj_out(LoadBarrierNode::Oop));
1241         }
1242       }
1243       phase->register_new_node(phi, region);
1244       replace_barrier(phase, lb, phi);
1245 
1246       if (region->is_Loop()) {
1247         // Load barrier moved to the back edge of the Loop may now
1248         // have a safepoint on the path to the barrier on the Similar
1249         // edge
1250         igvn.replace_input_of(phi->in(LoopNode::LoopBackControl)->in(0), LoadBarrierNode::Similar, C->top());
1251         Node* head = region->in(LoopNode::EntryControl);
1252         phase->set_idom(region, head, phase->dom_depth(head)+1);
1253         phase->recompute_dom_depth();
1254         if (head->is_CountedLoop() && head->as_CountedLoop()->is_main_loop()) {
1255           head->as_CountedLoop()->set_normal_loop();
1256         }
1257       }
1258 
1259       return true;
1260     }
1261   }
1262 
1263   return false;
1264 }
1265 
1266 static bool move_out_of_loop(PhaseIdealLoop* phase, LoadBarrierNode* lb) {
1267   PhaseIterGVN &igvn = phase->igvn();
1268   IdealLoopTree *lb_loop = phase->get_loop(lb->in(0));
1269   if (lb_loop != phase->ltree_root() && !lb_loop->_irreducible) {
1270     Node* oop_ctrl = phase->get_ctrl(lb->in(LoadBarrierNode::Oop));
1271     IdealLoopTree *oop_loop = phase->get_loop(oop_ctrl);
1272     IdealLoopTree* adr_loop = phase->get_loop(phase->get_ctrl(lb->in(LoadBarrierNode::Address)));
1273     if (!lb_loop->is_member(oop_loop) && !lb_loop->is_member(adr_loop)) {
1274       // That transformation may cause the Similar edge on dominated load barriers to be invalid
1275       lb->fix_similar_in_uses(&igvn);
1276 
1277       Node* head = lb_loop->_head;
1278       assert(head->is_Loop(), "");
1279 
1280       if (phase->is_dominator(head, oop_ctrl)) {
1281         assert(oop_ctrl->Opcode() == Op_CProj && oop_ctrl->in(0)->Opcode() == Op_NeverBranch, "");
1282         assert(lb_loop->is_member(phase->get_loop(oop_ctrl->in(0)->in(0))), "");
1283         return false;
1284       }
1285 
1286       if (head->is_CountedLoop()) {
1287         CountedLoopNode* cloop = head->as_CountedLoop();
1288         if (cloop->is_main_loop()) {
1289           cloop->set_normal_loop();
1290         }
1291         // When we are moving barrier out of a counted loop,
1292         // make sure we move it all the way out of the strip mined outer loop.
1293         if (cloop->is_strip_mined()) {
1294           head = cloop->outer_loop();
1295         }
1296       }
1297 
1298       Node* mem = lb->in(LoadBarrierNode::Memory);
1299       Node* m = find_dominating_memory(phase, mem, head, -1);
1300 
1301       LoadBarrierNode* new_lb = clone_load_barrier(phase, lb, head->in(LoopNode::EntryControl), m, NULL);
1302 
1303       assert(phase->idom(head) == head->in(LoopNode::EntryControl), "");
1304       Node* proj_ctl = new_lb->proj_out(LoadBarrierNode::Control);
1305       igvn.replace_input_of(head, LoopNode::EntryControl, proj_ctl);
1306       phase->set_idom(head, proj_ctl, phase->dom_depth(proj_ctl) + 1);
1307 
1308       replace_barrier(phase, lb, new_lb->proj_out(LoadBarrierNode::Oop));
1309 
1310       phase->recompute_dom_depth();
1311 
1312       return true;
1313     }
1314   }
1315 
1316   return false;
1317 }
1318 
1319 static bool common_barriers(PhaseIdealLoop* phase, LoadBarrierNode* lb) {
1320   PhaseIterGVN &igvn = phase->igvn();
1321   Node* in_val = lb->in(LoadBarrierNode::Oop);
1322   for (DUIterator_Fast imax, i = in_val->fast_outs(imax); i < imax; i++) {
1323     Node* u = in_val->fast_out(i);
1324     if (u != lb && u->is_LoadBarrier() && u->as_LoadBarrier()->has_true_uses()) {
1325       Node* this_ctrl = lb->in(LoadBarrierNode::Control);
1326       Node* other_ctrl = u->in(LoadBarrierNode::Control);
1327 
1328       Node* lca = phase->dom_lca(this_ctrl, other_ctrl);
1329       Node* proj1 = NULL;
1330       Node* proj2 = NULL;
1331       bool ok = (lb->in(LoadBarrierNode::Address) == u->in(LoadBarrierNode::Address));
1332 
1333       while (this_ctrl != lca && ok) {
1334         if (this_ctrl->in(0) != NULL &&
1335             this_ctrl->in(0)->is_MultiBranch()) {
1336           if (this_ctrl->in(0)->in(0) == lca) {
1337             assert(proj1 == NULL, "");
1338             assert(this_ctrl->is_Proj(), "");
1339             proj1 = this_ctrl;
1340           } else if (!(this_ctrl->in(0)->is_If() && this_ctrl->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none))) {
1341             ok = false;
1342           }
1343         }
1344         this_ctrl = phase->idom(this_ctrl);
1345       }
1346       while (other_ctrl != lca && ok) {
1347         if (other_ctrl->in(0) != NULL &&
1348             other_ctrl->in(0)->is_MultiBranch()) {
1349           if (other_ctrl->in(0)->in(0) == lca) {
1350             assert(other_ctrl->is_Proj(), "");
1351             assert(proj2 == NULL, "");
1352             proj2 = other_ctrl;
1353           } else if (!(other_ctrl->in(0)->is_If() && other_ctrl->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none))) {
1354             ok = false;
1355           }
1356         }
1357         other_ctrl = phase->idom(other_ctrl);
1358       }
1359       assert(proj1 == NULL || proj2 == NULL || proj1->in(0) == proj2->in(0), "");
1360       if (ok && proj1 && proj2 && proj1 != proj2 && proj1->in(0)->is_If()) {
1361         // That transformation may cause the Similar edge on dominated load barriers to be invalid
1362         lb->fix_similar_in_uses(&igvn);
1363         u->as_LoadBarrier()->fix_similar_in_uses(&igvn);
1364 
1365         Node* split = lca->unique_ctrl_out();
1366         assert(split->in(0) == lca, "");
1367 
1368         Node* mem = lb->in(LoadBarrierNode::Memory);
1369         Node* m = find_dominating_memory(phase, mem, split, -1);
1370         LoadBarrierNode* new_lb = clone_load_barrier(phase, lb, lca, m, NULL);
1371 
1372         Node* proj_ctl = new_lb->proj_out(LoadBarrierNode::Control);
1373         igvn.replace_input_of(split, 0, new_lb->proj_out(LoadBarrierNode::Control));
1374         phase->set_idom(split, proj_ctl, phase->dom_depth(proj_ctl)+1);
1375 
1376         Node* proj_oop = new_lb->proj_out(LoadBarrierNode::Oop);
1377         replace_barrier(phase, lb, proj_oop);
1378         replace_barrier(phase, u->as_LoadBarrier(), proj_oop);
1379 
1380         phase->recompute_dom_depth();
1381 
1382         return true;
1383       }
1384     }
1385   }
1386 
1387   return false;
1388 }
1389 
1390 static void optimize_load_barrier(PhaseIdealLoop* phase, LoadBarrierNode* lb, bool last_round) {
1391   Compile* C = Compile::current();
1392 
1393   if (!C->directive()->ZOptimizeLoadBarriersOption) {
1394     return;
1395   }
1396 
1397   if (lb->has_true_uses()) {
1398     if (replace_with_dominating_barrier(phase, lb, last_round)) {
1399       return;
1400     }
1401 
1402     if (split_barrier_thru_phi(phase, lb)) {
1403       return;
1404     }
1405 
1406     if (move_out_of_loop(phase, lb)) {
1407       return;
1408     }
1409 
1410     if (common_barriers(phase, lb)) {
1411       return;
1412     }
1413   }
1414 }
1415 
1416 void ZBarrierSetC2::loop_optimize_gc_barrier(PhaseIdealLoop* phase, Node* node, bool last_round) {
1417   if (node->is_LoadBarrier()) {
1418     optimize_load_barrier(phase, node->as_LoadBarrier(), last_round);
1419   }
1420 }
1421 
1422 Node* ZBarrierSetC2::step_over_gc_barrier(Node* c) const {
1423   Node* node = c;
1424 
1425   // 1. This step follows potential oop projections of a load barrier before expansion
1426   if (node->is_Proj()) {
1427     node = node->in(0);
1428   }
1429 
1430   // 2. This step checks for unexpanded load barriers
1431   if (node->is_LoadBarrier()) {
1432     return node->in(LoadBarrierNode::Oop);
1433   }
1434 
1435   // 3. This step checks for the phi corresponding to an optimized load barrier expansion
1436   if (node->is_Phi()) {
1437     PhiNode* phi = node->as_Phi();
1438     Node* n = phi->in(1);
1439     if (n != NULL && (n->is_LoadBarrierSlowReg() ||  n->is_LoadBarrierWeakSlowReg())) {
1440       assert(c == node, "projections from step 1 should only be seen before macro expansion");
1441       return phi->in(2);
1442     }
1443   }
1444 
1445   return c;
1446 }
1447 
1448 // == Verification ==
1449 
1450 #ifdef ASSERT
1451 
1452 static bool look_for_barrier(Node* n, bool post_parse, VectorSet& visited) {
1453   if (visited.test_set(n->_idx)) {
1454     return true;
1455   }
1456 
1457   for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
1458     Node* u = n->fast_out(i);
1459     if (u->is_LoadBarrier()) {
1460     } else if ((u->is_Phi() || u->is_CMove()) && !post_parse) {
1461       if (!look_for_barrier(u, post_parse, visited)) {
1462         return false;
1463       }
1464     } else if (u->Opcode() == Op_EncodeP || u->Opcode() == Op_DecodeN) {
1465       if (!look_for_barrier(u, post_parse, visited)) {
1466         return false;
1467       }
1468     } else if (u->Opcode() != Op_SCMemProj) {
1469       tty->print("bad use"); u->dump();
1470       return false;
1471     }
1472   }
1473 
1474   return true;
1475 }
1476 
1477 void ZBarrierSetC2::verify_gc_barriers(bool post_parse) const {
1478   ZBarrierSetC2State* s = state();
1479   Compile* C = Compile::current();
1480   ResourceMark rm;
1481   VectorSet visited(Thread::current()->resource_area());
1482   for (int i = 0; i < s->load_barrier_count(); i++) {
1483     LoadBarrierNode* n = s->load_barrier_node(i);
1484 
1485     // The dominating barrier on the same address if it exists and
1486     // this barrier must not be applied on the value from the same
1487     // load otherwise the value is not reloaded before it's used the
1488     // second time.
1489     assert(n->in(LoadBarrierNode::Similar)->is_top() ||
1490            (n->in(LoadBarrierNode::Similar)->in(0)->is_LoadBarrier() &&
1491             n->in(LoadBarrierNode::Similar)->in(0)->in(LoadBarrierNode::Address) == n->in(LoadBarrierNode::Address) &&
1492             n->in(LoadBarrierNode::Similar)->in(0)->in(LoadBarrierNode::Oop) != n->in(LoadBarrierNode::Oop)),
1493            "broken similar edge");
1494 
1495     assert(post_parse || n->as_LoadBarrier()->has_true_uses(),
1496            "found unneeded load barrier");
1497 
1498     // Several load barrier nodes chained through their Similar edge
1499     // break the code that remove the barriers in final graph reshape.
1500     assert(n->in(LoadBarrierNode::Similar)->is_top() ||
1501            (n->in(LoadBarrierNode::Similar)->in(0)->is_LoadBarrier() &&
1502             n->in(LoadBarrierNode::Similar)->in(0)->in(LoadBarrierNode::Similar)->is_top()),
1503            "chain of Similar load barriers");
1504 
1505     if (!n->in(LoadBarrierNode::Similar)->is_top()) {
1506       ResourceMark rm;
1507       Unique_Node_List wq;
1508       Node* other = n->in(LoadBarrierNode::Similar)->in(0);
1509       wq.push(n);
1510       bool ok = true;
1511       bool dom_found = false;
1512       for (uint next = 0; next < wq.size(); ++next) {
1513         Node *n = wq.at(next);
1514         assert(n->is_CFG(), "");
1515         assert(!n->is_SafePoint(), "");
1516 
1517         if (n == other) {
1518           continue;
1519         }
1520 
1521         if (n->is_Region()) {
1522           for (uint i = 1; i < n->req(); i++) {
1523             Node* m = n->in(i);
1524             if (m != NULL) {
1525               wq.push(m);
1526             }
1527           }
1528         } else {
1529           Node* m = n->in(0);
1530           if (m != NULL) {
1531             wq.push(m);
1532           }
1533         }
1534       }
1535     }
1536 
1537     if (ZVerifyLoadBarriers) {
1538       if ((n->is_Load() || n->is_LoadStore()) && n->bottom_type()->make_oopptr() != NULL) {
1539         visited.Clear();
1540         bool found = look_for_barrier(n, post_parse, visited);
1541         if (!found) {
1542           n->dump(1);
1543           n->dump(-3);
1544           stringStream ss;
1545           C->method()->print_short_name(&ss);
1546           tty->print_cr("-%s-", ss.as_string());
1547           assert(found, "");
1548         }
1549       }
1550     }
1551   }
1552 }
1553 
1554 #endif