1 /*
   2  * Copyright (c) 2001, 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 "gc/g1/g1SATBCardTableModRefBS.hpp"
  28 #include "gc/g1/heapRegion.hpp"
  29 #include "gc/shared/barrierSet.hpp"
  30 #include "gc/shared/cardTableModRefBS.hpp"
  31 #include "gc/shared/collectedHeap.hpp"
  32 #include "memory/resourceArea.hpp"
  33 #include "opto/addnode.hpp"
  34 #include "opto/castnode.hpp"
  35 #include "opto/convertnode.hpp"
  36 #include "opto/graphKit.hpp"
  37 #include "opto/idealKit.hpp"
  38 #include "opto/intrinsicnode.hpp"
  39 #include "opto/locknode.hpp"
  40 #include "opto/machnode.hpp"

  41 #include "opto/opaquenode.hpp"
  42 #include "opto/parse.hpp"
  43 #include "opto/rootnode.hpp"
  44 #include "opto/runtime.hpp"
  45 #include "runtime/deoptimization.hpp"
  46 #include "runtime/sharedRuntime.hpp"
  47 
  48 //----------------------------GraphKit-----------------------------------------
  49 // Main utility constructor.
  50 GraphKit::GraphKit(JVMState* jvms)
  51   : Phase(Phase::Parser),
  52     _env(C->env()),
  53     _gvn(*C->initial_gvn())
  54 {
  55   _exceptions = jvms->map()->next_exception();
  56   if (_exceptions != NULL)  jvms->map()->set_next_exception(NULL);
  57   set_jvms(jvms);
  58 }
  59 
  60 // Private constructor for parser.
  61 GraphKit::GraphKit()
  62   : Phase(Phase::Parser),
  63     _env(C->env()),
  64     _gvn(*C->initial_gvn())
  65 {
  66   _exceptions = NULL;
  67   set_map(NULL);
  68   debug_only(_sp = -99);
  69   debug_only(set_bci(-99));
  70 }
  71 
  72 
  73 
  74 //---------------------------clean_stack---------------------------------------
  75 // Clear away rubbish from the stack area of the JVM state.
  76 // This destroys any arguments that may be waiting on the stack.
  77 void GraphKit::clean_stack(int from_sp) {
  78   SafePointNode* map      = this->map();
  79   JVMState*      jvms     = this->jvms();
  80   int            stk_size = jvms->stk_size();
  81   int            stkoff   = jvms->stkoff();
  82   Node*          top      = this->top();
  83   for (int i = from_sp; i < stk_size; i++) {
  84     if (map->in(stkoff + i) != top) {
  85       map->set_req(stkoff + i, top);
  86     }
  87   }
  88 }
  89 
  90 
  91 //--------------------------------sync_jvms-----------------------------------
  92 // Make sure our current jvms agrees with our parse state.
  93 JVMState* GraphKit::sync_jvms() const {
  94   JVMState* jvms = this->jvms();
  95   jvms->set_bci(bci());       // Record the new bci in the JVMState
  96   jvms->set_sp(sp());         // Record the new sp in the JVMState
  97   assert(jvms_in_sync(), "jvms is now in sync");
  98   return jvms;
  99 }
 100 
 101 //--------------------------------sync_jvms_for_reexecute---------------------
 102 // Make sure our current jvms agrees with our parse state.  This version
 103 // uses the reexecute_sp for reexecuting bytecodes.
 104 JVMState* GraphKit::sync_jvms_for_reexecute() {
 105   JVMState* jvms = this->jvms();
 106   jvms->set_bci(bci());          // Record the new bci in the JVMState
 107   jvms->set_sp(reexecute_sp());  // Record the new sp in the JVMState
 108   return jvms;
 109 }
 110 
 111 #ifdef ASSERT
 112 bool GraphKit::jvms_in_sync() const {
 113   Parse* parse = is_Parse();
 114   if (parse == NULL) {
 115     if (bci() !=      jvms()->bci())          return false;
 116     if (sp()  != (int)jvms()->sp())           return false;
 117     return true;
 118   }
 119   if (jvms()->method() != parse->method())    return false;
 120   if (jvms()->bci()    != parse->bci())       return false;
 121   int jvms_sp = jvms()->sp();
 122   if (jvms_sp          != parse->sp())        return false;
 123   int jvms_depth = jvms()->depth();
 124   if (jvms_depth       != parse->depth())     return false;
 125   return true;
 126 }
 127 
 128 // Local helper checks for special internal merge points
 129 // used to accumulate and merge exception states.
 130 // They are marked by the region's in(0) edge being the map itself.
 131 // Such merge points must never "escape" into the parser at large,
 132 // until they have been handed to gvn.transform.
 133 static bool is_hidden_merge(Node* reg) {
 134   if (reg == NULL)  return false;
 135   if (reg->is_Phi()) {
 136     reg = reg->in(0);
 137     if (reg == NULL)  return false;
 138   }
 139   return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root();
 140 }
 141 
 142 void GraphKit::verify_map() const {
 143   if (map() == NULL)  return;  // null map is OK
 144   assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
 145   assert(!map()->has_exceptions(),    "call add_exception_states_from 1st");
 146   assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
 147 }
 148 
 149 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
 150   assert(ex_map->next_exception() == NULL, "not already part of a chain");
 151   assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
 152 }
 153 #endif
 154 
 155 //---------------------------stop_and_kill_map---------------------------------
 156 // Set _map to NULL, signalling a stop to further bytecode execution.
 157 // First smash the current map's control to a constant, to mark it dead.
 158 void GraphKit::stop_and_kill_map() {
 159   SafePointNode* dead_map = stop();
 160   if (dead_map != NULL) {
 161     dead_map->disconnect_inputs(NULL, C); // Mark the map as killed.
 162     assert(dead_map->is_killed(), "must be so marked");
 163   }
 164 }
 165 
 166 
 167 //--------------------------------stopped--------------------------------------
 168 // Tell if _map is NULL, or control is top.
 169 bool GraphKit::stopped() {
 170   if (map() == NULL)           return true;
 171   else if (control() == top()) return true;
 172   else                         return false;
 173 }
 174 
 175 
 176 //-----------------------------has_ex_handler----------------------------------
 177 // Tell if this method or any caller method has exception handlers.
 178 bool GraphKit::has_ex_handler() {
 179   for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) {
 180     if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
 181       return true;
 182     }
 183   }
 184   return false;
 185 }
 186 
 187 //------------------------------save_ex_oop------------------------------------
 188 // Save an exception without blowing stack contents or other JVM state.
 189 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
 190   assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
 191   ex_map->add_req(ex_oop);
 192   debug_only(verify_exception_state(ex_map));
 193 }
 194 
 195 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
 196   assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
 197   Node* ex_oop = ex_map->in(ex_map->req()-1);
 198   if (clear_it)  ex_map->del_req(ex_map->req()-1);
 199   return ex_oop;
 200 }
 201 
 202 //-----------------------------saved_ex_oop------------------------------------
 203 // Recover a saved exception from its map.
 204 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
 205   return common_saved_ex_oop(ex_map, false);
 206 }
 207 
 208 //--------------------------clear_saved_ex_oop---------------------------------
 209 // Erase a previously saved exception from its map.
 210 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
 211   return common_saved_ex_oop(ex_map, true);
 212 }
 213 
 214 #ifdef ASSERT
 215 //---------------------------has_saved_ex_oop----------------------------------
 216 // Erase a previously saved exception from its map.
 217 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
 218   return ex_map->req() == ex_map->jvms()->endoff()+1;
 219 }
 220 #endif
 221 
 222 //-------------------------make_exception_state--------------------------------
 223 // Turn the current JVM state into an exception state, appending the ex_oop.
 224 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
 225   sync_jvms();
 226   SafePointNode* ex_map = stop();  // do not manipulate this map any more
 227   set_saved_ex_oop(ex_map, ex_oop);
 228   return ex_map;
 229 }
 230 
 231 
 232 //--------------------------add_exception_state--------------------------------
 233 // Add an exception to my list of exceptions.
 234 void GraphKit::add_exception_state(SafePointNode* ex_map) {
 235   if (ex_map == NULL || ex_map->control() == top()) {
 236     return;
 237   }
 238 #ifdef ASSERT
 239   verify_exception_state(ex_map);
 240   if (has_exceptions()) {
 241     assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
 242   }
 243 #endif
 244 
 245   // If there is already an exception of exactly this type, merge with it.
 246   // In particular, null-checks and other low-level exceptions common up here.
 247   Node*       ex_oop  = saved_ex_oop(ex_map);
 248   const Type* ex_type = _gvn.type(ex_oop);
 249   if (ex_oop == top()) {
 250     // No action needed.
 251     return;
 252   }
 253   assert(ex_type->isa_instptr(), "exception must be an instance");
 254   for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) {
 255     const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
 256     // We check sp also because call bytecodes can generate exceptions
 257     // both before and after arguments are popped!
 258     if (ex_type2 == ex_type
 259         && e2->_jvms->sp() == ex_map->_jvms->sp()) {
 260       combine_exception_states(ex_map, e2);
 261       return;
 262     }
 263   }
 264 
 265   // No pre-existing exception of the same type.  Chain it on the list.
 266   push_exception_state(ex_map);
 267 }
 268 
 269 //-----------------------add_exception_states_from-----------------------------
 270 void GraphKit::add_exception_states_from(JVMState* jvms) {
 271   SafePointNode* ex_map = jvms->map()->next_exception();
 272   if (ex_map != NULL) {
 273     jvms->map()->set_next_exception(NULL);
 274     for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) {
 275       next_map = ex_map->next_exception();
 276       ex_map->set_next_exception(NULL);
 277       add_exception_state(ex_map);
 278     }
 279   }
 280 }
 281 
 282 //-----------------------transfer_exceptions_into_jvms-------------------------
 283 JVMState* GraphKit::transfer_exceptions_into_jvms() {
 284   if (map() == NULL) {
 285     // We need a JVMS to carry the exceptions, but the map has gone away.
 286     // Create a scratch JVMS, cloned from any of the exception states...
 287     if (has_exceptions()) {
 288       _map = _exceptions;
 289       _map = clone_map();
 290       _map->set_next_exception(NULL);
 291       clear_saved_ex_oop(_map);
 292       debug_only(verify_map());
 293     } else {
 294       // ...or created from scratch
 295       JVMState* jvms = new (C) JVMState(_method, NULL);
 296       jvms->set_bci(_bci);
 297       jvms->set_sp(_sp);
 298       jvms->set_map(new SafePointNode(TypeFunc::Parms, jvms));
 299       set_jvms(jvms);
 300       for (uint i = 0; i < map()->req(); i++)  map()->init_req(i, top());
 301       set_all_memory(top());
 302       while (map()->req() < jvms->endoff())  map()->add_req(top());
 303     }
 304     // (This is a kludge, in case you didn't notice.)
 305     set_control(top());
 306   }
 307   JVMState* jvms = sync_jvms();
 308   assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
 309   jvms->map()->set_next_exception(_exceptions);
 310   _exceptions = NULL;   // done with this set of exceptions
 311   return jvms;
 312 }
 313 
 314 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
 315   assert(is_hidden_merge(dstphi), "must be a special merge node");
 316   assert(is_hidden_merge(srcphi), "must be a special merge node");
 317   uint limit = srcphi->req();
 318   for (uint i = PhiNode::Input; i < limit; i++) {
 319     dstphi->add_req(srcphi->in(i));
 320   }
 321 }
 322 static inline void add_one_req(Node* dstphi, Node* src) {
 323   assert(is_hidden_merge(dstphi), "must be a special merge node");
 324   assert(!is_hidden_merge(src), "must not be a special merge node");
 325   dstphi->add_req(src);
 326 }
 327 
 328 //-----------------------combine_exception_states------------------------------
 329 // This helper function combines exception states by building phis on a
 330 // specially marked state-merging region.  These regions and phis are
 331 // untransformed, and can build up gradually.  The region is marked by
 332 // having a control input of its exception map, rather than NULL.  Such
 333 // regions do not appear except in this function, and in use_exception_state.
 334 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
 335   if (failing())  return;  // dying anyway...
 336   JVMState* ex_jvms = ex_map->_jvms;
 337   assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
 338   assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
 339   assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
 340   assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
 341   assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects");
 342   assert(ex_map->req() == phi_map->req(), "matching maps");
 343   uint tos = ex_jvms->stkoff() + ex_jvms->sp();
 344   Node*         hidden_merge_mark = root();
 345   Node*         region  = phi_map->control();
 346   MergeMemNode* phi_mem = phi_map->merged_memory();
 347   MergeMemNode* ex_mem  = ex_map->merged_memory();
 348   if (region->in(0) != hidden_merge_mark) {
 349     // The control input is not (yet) a specially-marked region in phi_map.
 350     // Make it so, and build some phis.
 351     region = new RegionNode(2);
 352     _gvn.set_type(region, Type::CONTROL);
 353     region->set_req(0, hidden_merge_mark);  // marks an internal ex-state
 354     region->init_req(1, phi_map->control());
 355     phi_map->set_control(region);
 356     Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
 357     record_for_igvn(io_phi);
 358     _gvn.set_type(io_phi, Type::ABIO);
 359     phi_map->set_i_o(io_phi);
 360     for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
 361       Node* m = mms.memory();
 362       Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
 363       record_for_igvn(m_phi);
 364       _gvn.set_type(m_phi, Type::MEMORY);
 365       mms.set_memory(m_phi);
 366     }
 367   }
 368 
 369   // Either or both of phi_map and ex_map might already be converted into phis.
 370   Node* ex_control = ex_map->control();
 371   // if there is special marking on ex_map also, we add multiple edges from src
 372   bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
 373   // how wide was the destination phi_map, originally?
 374   uint orig_width = region->req();
 375 
 376   if (add_multiple) {
 377     add_n_reqs(region, ex_control);
 378     add_n_reqs(phi_map->i_o(), ex_map->i_o());
 379   } else {
 380     // ex_map has no merges, so we just add single edges everywhere
 381     add_one_req(region, ex_control);
 382     add_one_req(phi_map->i_o(), ex_map->i_o());
 383   }
 384   for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
 385     if (mms.is_empty()) {
 386       // get a copy of the base memory, and patch some inputs into it
 387       const TypePtr* adr_type = mms.adr_type(C);
 388       Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
 389       assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
 390       mms.set_memory(phi);
 391       // Prepare to append interesting stuff onto the newly sliced phi:
 392       while (phi->req() > orig_width)  phi->del_req(phi->req()-1);
 393     }
 394     // Append stuff from ex_map:
 395     if (add_multiple) {
 396       add_n_reqs(mms.memory(), mms.memory2());
 397     } else {
 398       add_one_req(mms.memory(), mms.memory2());
 399     }
 400   }
 401   uint limit = ex_map->req();
 402   for (uint i = TypeFunc::Parms; i < limit; i++) {
 403     // Skip everything in the JVMS after tos.  (The ex_oop follows.)
 404     if (i == tos)  i = ex_jvms->monoff();
 405     Node* src = ex_map->in(i);
 406     Node* dst = phi_map->in(i);
 407     if (src != dst) {
 408       PhiNode* phi;
 409       if (dst->in(0) != region) {
 410         dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
 411         record_for_igvn(phi);
 412         _gvn.set_type(phi, phi->type());
 413         phi_map->set_req(i, dst);
 414         // Prepare to append interesting stuff onto the new phi:
 415         while (dst->req() > orig_width)  dst->del_req(dst->req()-1);
 416       } else {
 417         assert(dst->is_Phi(), "nobody else uses a hidden region");
 418         phi = dst->as_Phi();
 419       }
 420       if (add_multiple && src->in(0) == ex_control) {
 421         // Both are phis.
 422         add_n_reqs(dst, src);
 423       } else {
 424         while (dst->req() < region->req())  add_one_req(dst, src);
 425       }
 426       const Type* srctype = _gvn.type(src);
 427       if (phi->type() != srctype) {
 428         const Type* dsttype = phi->type()->meet_speculative(srctype);
 429         if (phi->type() != dsttype) {
 430           phi->set_type(dsttype);
 431           _gvn.set_type(phi, dsttype);
 432         }
 433       }
 434     }
 435   }
 436   phi_map->merge_replaced_nodes_with(ex_map);
 437 }
 438 
 439 //--------------------------use_exception_state--------------------------------
 440 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
 441   if (failing()) { stop(); return top(); }
 442   Node* region = phi_map->control();
 443   Node* hidden_merge_mark = root();
 444   assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
 445   Node* ex_oop = clear_saved_ex_oop(phi_map);
 446   if (region->in(0) == hidden_merge_mark) {
 447     // Special marking for internal ex-states.  Process the phis now.
 448     region->set_req(0, region);  // now it's an ordinary region
 449     set_jvms(phi_map->jvms());   // ...so now we can use it as a map
 450     // Note: Setting the jvms also sets the bci and sp.
 451     set_control(_gvn.transform(region));
 452     uint tos = jvms()->stkoff() + sp();
 453     for (uint i = 1; i < tos; i++) {
 454       Node* x = phi_map->in(i);
 455       if (x->in(0) == region) {
 456         assert(x->is_Phi(), "expected a special phi");
 457         phi_map->set_req(i, _gvn.transform(x));
 458       }
 459     }
 460     for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
 461       Node* x = mms.memory();
 462       if (x->in(0) == region) {
 463         assert(x->is_Phi(), "nobody else uses a hidden region");
 464         mms.set_memory(_gvn.transform(x));
 465       }
 466     }
 467     if (ex_oop->in(0) == region) {
 468       assert(ex_oop->is_Phi(), "expected a special phi");
 469       ex_oop = _gvn.transform(ex_oop);
 470     }
 471   } else {
 472     set_jvms(phi_map->jvms());
 473   }
 474 
 475   assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
 476   assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
 477   return ex_oop;
 478 }
 479 
 480 //---------------------------------java_bc-------------------------------------
 481 Bytecodes::Code GraphKit::java_bc() const {
 482   ciMethod* method = this->method();
 483   int       bci    = this->bci();
 484   if (method != NULL && bci != InvocationEntryBci)
 485     return method->java_code_at_bci(bci);
 486   else
 487     return Bytecodes::_illegal;
 488 }
 489 
 490 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
 491                                                           bool must_throw) {
 492     // if the exception capability is set, then we will generate code
 493     // to check the JavaThread.should_post_on_exceptions flag to see
 494     // if we actually need to report exception events (for this
 495     // thread).  If we don't need to report exception events, we will
 496     // take the normal fast path provided by add_exception_events.  If
 497     // exception event reporting is enabled for this thread, we will
 498     // take the uncommon_trap in the BuildCutout below.
 499 
 500     // first must access the should_post_on_exceptions_flag in this thread's JavaThread
 501     Node* jthread = _gvn.transform(new ThreadLocalNode());
 502     Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
 503     Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw, MemNode::unordered);
 504 
 505     // Test the should_post_on_exceptions_flag vs. 0
 506     Node* chk = _gvn.transform( new CmpINode(should_post_flag, intcon(0)) );
 507     Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
 508 
 509     // Branch to slow_path if should_post_on_exceptions_flag was true
 510     { BuildCutout unless(this, tst, PROB_MAX);
 511       // Do not try anything fancy if we're notifying the VM on every throw.
 512       // Cf. case Bytecodes::_athrow in parse2.cpp.
 513       uncommon_trap(reason, Deoptimization::Action_none,
 514                     (ciKlass*)NULL, (char*)NULL, must_throw);
 515     }
 516 
 517 }
 518 
 519 //------------------------------builtin_throw----------------------------------
 520 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) {
 521   bool must_throw = true;
 522 
 523   if (env()->jvmti_can_post_on_exceptions()) {
 524     // check if we must post exception events, take uncommon trap if so
 525     uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
 526     // here if should_post_on_exceptions is false
 527     // continue on with the normal codegen
 528   }
 529 
 530   // If this particular condition has not yet happened at this
 531   // bytecode, then use the uncommon trap mechanism, and allow for
 532   // a future recompilation if several traps occur here.
 533   // If the throw is hot, try to use a more complicated inline mechanism
 534   // which keeps execution inside the compiled code.
 535   bool treat_throw_as_hot = false;
 536   ciMethodData* md = method()->method_data();
 537 
 538   if (ProfileTraps) {
 539     if (too_many_traps(reason)) {
 540       treat_throw_as_hot = true;
 541     }
 542     // (If there is no MDO at all, assume it is early in
 543     // execution, and that any deopts are part of the
 544     // startup transient, and don't need to be remembered.)
 545 
 546     // Also, if there is a local exception handler, treat all throws
 547     // as hot if there has been at least one in this method.
 548     if (C->trap_count(reason) != 0
 549         && method()->method_data()->trap_count(reason) != 0
 550         && has_ex_handler()) {
 551         treat_throw_as_hot = true;
 552     }
 553   }
 554 
 555   // If this throw happens frequently, an uncommon trap might cause
 556   // a performance pothole.  If there is a local exception handler,
 557   // and if this particular bytecode appears to be deoptimizing often,
 558   // let us handle the throw inline, with a preconstructed instance.
 559   // Note:   If the deopt count has blown up, the uncommon trap
 560   // runtime is going to flush this nmethod, not matter what.
 561   if (treat_throw_as_hot
 562       && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) {
 563     // If the throw is local, we use a pre-existing instance and
 564     // punt on the backtrace.  This would lead to a missing backtrace
 565     // (a repeat of 4292742) if the backtrace object is ever asked
 566     // for its backtrace.
 567     // Fixing this remaining case of 4292742 requires some flavor of
 568     // escape analysis.  Leave that for the future.
 569     ciInstance* ex_obj = NULL;
 570     switch (reason) {
 571     case Deoptimization::Reason_null_check:
 572       ex_obj = env()->NullPointerException_instance();
 573       break;
 574     case Deoptimization::Reason_div0_check:
 575       ex_obj = env()->ArithmeticException_instance();
 576       break;
 577     case Deoptimization::Reason_range_check:
 578       ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
 579       break;
 580     case Deoptimization::Reason_class_check:
 581       if (java_bc() == Bytecodes::_aastore) {
 582         ex_obj = env()->ArrayStoreException_instance();
 583       } else {
 584         ex_obj = env()->ClassCastException_instance();
 585       }
 586       break;
 587     default:
 588       break;
 589     }
 590     if (failing()) { stop(); return; }  // exception allocation might fail
 591     if (ex_obj != NULL) {
 592       // Cheat with a preallocated exception object.
 593       if (C->log() != NULL)
 594         C->log()->elem("hot_throw preallocated='1' reason='%s'",
 595                        Deoptimization::trap_reason_name(reason));
 596       const TypeInstPtr* ex_con  = TypeInstPtr::make(ex_obj);
 597       Node*              ex_node = _gvn.transform(ConNode::make(ex_con));
 598 
 599       // Clear the detail message of the preallocated exception object.
 600       // Weblogic sometimes mutates the detail message of exceptions
 601       // using reflection.
 602       int offset = java_lang_Throwable::get_detailMessage_offset();
 603       const TypePtr* adr_typ = ex_con->add_offset(offset);
 604 
 605       Node *adr = basic_plus_adr(ex_node, ex_node, offset);
 606       const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
 607       // Conservatively release stores of object references.
 608       Node *store = store_oop_to_object(control(), ex_node, adr, adr_typ, null(), val_type, T_OBJECT, MemNode::release);
 609 
 610       add_exception_state(make_exception_state(ex_node));
 611       return;
 612     }
 613   }
 614 
 615   // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
 616   // It won't be much cheaper than bailing to the interp., since we'll
 617   // have to pass up all the debug-info, and the runtime will have to
 618   // create the stack trace.
 619 
 620   // Usual case:  Bail to interpreter.
 621   // Reserve the right to recompile if we haven't seen anything yet.
 622 
 623   ciMethod* m = Deoptimization::reason_is_speculate(reason) ? C->method() : NULL;
 624   Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
 625   if (treat_throw_as_hot
 626       && (method()->method_data()->trap_recompiled_at(bci(), m)
 627           || C->too_many_traps(reason))) {
 628     // We cannot afford to take more traps here.  Suffer in the interpreter.
 629     if (C->log() != NULL)
 630       C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
 631                      Deoptimization::trap_reason_name(reason),
 632                      C->trap_count(reason));
 633     action = Deoptimization::Action_none;
 634   }
 635 
 636   // "must_throw" prunes the JVM state to include only the stack, if there
 637   // are no local exception handlers.  This should cut down on register
 638   // allocation time and code size, by drastically reducing the number
 639   // of in-edges on the call to the uncommon trap.
 640 
 641   uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw);
 642 }
 643 
 644 
 645 //----------------------------PreserveJVMState---------------------------------
 646 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
 647   debug_only(kit->verify_map());
 648   _kit    = kit;
 649   _map    = kit->map();   // preserve the map
 650   _sp     = kit->sp();
 651   kit->set_map(clone_map ? kit->clone_map() : NULL);
 652 #ifdef ASSERT
 653   _bci    = kit->bci();
 654   Parse* parser = kit->is_Parse();
 655   int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
 656   _block  = block;
 657 #endif
 658 }
 659 PreserveJVMState::~PreserveJVMState() {
 660   GraphKit* kit = _kit;
 661 #ifdef ASSERT
 662   assert(kit->bci() == _bci, "bci must not shift");
 663   Parse* parser = kit->is_Parse();
 664   int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
 665   assert(block == _block,    "block must not shift");
 666 #endif
 667   kit->set_map(_map);
 668   kit->set_sp(_sp);
 669 }
 670 
 671 
 672 //-----------------------------BuildCutout-------------------------------------
 673 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
 674   : PreserveJVMState(kit)
 675 {
 676   assert(p->is_Con() || p->is_Bool(), "test must be a bool");
 677   SafePointNode* outer_map = _map;   // preserved map is caller's
 678   SafePointNode* inner_map = kit->map();
 679   IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
 680   outer_map->set_control(kit->gvn().transform( new IfTrueNode(iff) ));
 681   inner_map->set_control(kit->gvn().transform( new IfFalseNode(iff) ));
 682 }
 683 BuildCutout::~BuildCutout() {
 684   GraphKit* kit = _kit;
 685   assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
 686 }
 687 
 688 //---------------------------PreserveReexecuteState----------------------------
 689 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
 690   assert(!kit->stopped(), "must call stopped() before");
 691   _kit    =    kit;
 692   _sp     =    kit->sp();
 693   _reexecute = kit->jvms()->_reexecute;
 694 }
 695 PreserveReexecuteState::~PreserveReexecuteState() {
 696   if (_kit->stopped()) return;
 697   _kit->jvms()->_reexecute = _reexecute;
 698   _kit->set_sp(_sp);
 699 }
 700 
 701 //------------------------------clone_map--------------------------------------
 702 // Implementation of PreserveJVMState
 703 //
 704 // Only clone_map(...) here. If this function is only used in the
 705 // PreserveJVMState class we may want to get rid of this extra
 706 // function eventually and do it all there.
 707 
 708 SafePointNode* GraphKit::clone_map() {
 709   if (map() == NULL)  return NULL;
 710 
 711   // Clone the memory edge first
 712   Node* mem = MergeMemNode::make(map()->memory());
 713   gvn().set_type_bottom(mem);
 714 
 715   SafePointNode *clonemap = (SafePointNode*)map()->clone();
 716   JVMState* jvms = this->jvms();
 717   JVMState* clonejvms = jvms->clone_shallow(C);
 718   clonemap->set_memory(mem);
 719   clonemap->set_jvms(clonejvms);
 720   clonejvms->set_map(clonemap);
 721   record_for_igvn(clonemap);
 722   gvn().set_type_bottom(clonemap);
 723   return clonemap;
 724 }
 725 
 726 
 727 //-----------------------------set_map_clone-----------------------------------
 728 void GraphKit::set_map_clone(SafePointNode* m) {
 729   _map = m;
 730   _map = clone_map();
 731   _map->set_next_exception(NULL);
 732   debug_only(verify_map());
 733 }
 734 
 735 
 736 //----------------------------kill_dead_locals---------------------------------
 737 // Detect any locals which are known to be dead, and force them to top.
 738 void GraphKit::kill_dead_locals() {
 739   // Consult the liveness information for the locals.  If any
 740   // of them are unused, then they can be replaced by top().  This
 741   // should help register allocation time and cut down on the size
 742   // of the deoptimization information.
 743 
 744   // This call is made from many of the bytecode handling
 745   // subroutines called from the Big Switch in do_one_bytecode.
 746   // Every bytecode which might include a slow path is responsible
 747   // for killing its dead locals.  The more consistent we
 748   // are about killing deads, the fewer useless phis will be
 749   // constructed for them at various merge points.
 750 
 751   // bci can be -1 (InvocationEntryBci).  We return the entry
 752   // liveness for the method.
 753 
 754   if (method() == NULL || method()->code_size() == 0) {
 755     // We are building a graph for a call to a native method.
 756     // All locals are live.
 757     return;
 758   }
 759 
 760   ResourceMark rm;
 761 
 762   // Consult the liveness information for the locals.  If any
 763   // of them are unused, then they can be replaced by top().  This
 764   // should help register allocation time and cut down on the size
 765   // of the deoptimization information.
 766   MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
 767 
 768   int len = (int)live_locals.size();
 769   assert(len <= jvms()->loc_size(), "too many live locals");
 770   for (int local = 0; local < len; local++) {
 771     if (!live_locals.at(local)) {
 772       set_local(local, top());
 773     }
 774   }
 775 }
 776 
 777 #ifdef ASSERT
 778 //-------------------------dead_locals_are_killed------------------------------
 779 // Return true if all dead locals are set to top in the map.
 780 // Used to assert "clean" debug info at various points.
 781 bool GraphKit::dead_locals_are_killed() {
 782   if (method() == NULL || method()->code_size() == 0) {
 783     // No locals need to be dead, so all is as it should be.
 784     return true;
 785   }
 786 
 787   // Make sure somebody called kill_dead_locals upstream.
 788   ResourceMark rm;
 789   for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
 790     if (jvms->loc_size() == 0)  continue;  // no locals to consult
 791     SafePointNode* map = jvms->map();
 792     ciMethod* method = jvms->method();
 793     int       bci    = jvms->bci();
 794     if (jvms == this->jvms()) {
 795       bci = this->bci();  // it might not yet be synched
 796     }
 797     MethodLivenessResult live_locals = method->liveness_at_bci(bci);
 798     int len = (int)live_locals.size();
 799     if (!live_locals.is_valid() || len == 0)
 800       // This method is trivial, or is poisoned by a breakpoint.
 801       return true;
 802     assert(len == jvms->loc_size(), "live map consistent with locals map");
 803     for (int local = 0; local < len; local++) {
 804       if (!live_locals.at(local) && map->local(jvms, local) != top()) {
 805         if (PrintMiscellaneous && (Verbose || WizardMode)) {
 806           tty->print_cr("Zombie local %d: ", local);
 807           jvms->dump();
 808         }
 809         return false;
 810       }
 811     }
 812   }
 813   return true;
 814 }
 815 
 816 #endif //ASSERT
 817 
 818 // Helper function for enforcing certain bytecodes to reexecute if
 819 // deoptimization happens
 820 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
 821   ciMethod* cur_method = jvms->method();
 822   int       cur_bci   = jvms->bci();
 823   if (cur_method != NULL && cur_bci != InvocationEntryBci) {
 824     Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
 825     return Interpreter::bytecode_should_reexecute(code) ||
 826            (is_anewarray && code == Bytecodes::_multianewarray);
 827     // Reexecute _multianewarray bytecode which was replaced with
 828     // sequence of [a]newarray. See Parse::do_multianewarray().
 829     //
 830     // Note: interpreter should not have it set since this optimization
 831     // is limited by dimensions and guarded by flag so in some cases
 832     // multianewarray() runtime calls will be generated and
 833     // the bytecode should not be reexecutes (stack will not be reset).
 834   } else
 835     return false;
 836 }
 837 
 838 // Helper function for adding JVMState and debug information to node
 839 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
 840   // Add the safepoint edges to the call (or other safepoint).
 841 
 842   // Make sure dead locals are set to top.  This
 843   // should help register allocation time and cut down on the size
 844   // of the deoptimization information.
 845   assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
 846 
 847   // Walk the inline list to fill in the correct set of JVMState's
 848   // Also fill in the associated edges for each JVMState.
 849 
 850   // If the bytecode needs to be reexecuted we need to put
 851   // the arguments back on the stack.
 852   const bool should_reexecute = jvms()->should_reexecute();
 853   JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
 854 
 855   // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
 856   // undefined if the bci is different.  This is normal for Parse but it
 857   // should not happen for LibraryCallKit because only one bci is processed.
 858   assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
 859          "in LibraryCallKit the reexecute bit should not change");
 860 
 861   // If we are guaranteed to throw, we can prune everything but the
 862   // input to the current bytecode.
 863   bool can_prune_locals = false;
 864   uint stack_slots_not_pruned = 0;
 865   int inputs = 0, depth = 0;
 866   if (must_throw) {
 867     assert(method() == youngest_jvms->method(), "sanity");
 868     if (compute_stack_effects(inputs, depth)) {
 869       can_prune_locals = true;
 870       stack_slots_not_pruned = inputs;
 871     }
 872   }
 873 
 874   if (env()->should_retain_local_variables()) {
 875     // At any safepoint, this method can get breakpointed, which would
 876     // then require an immediate deoptimization.
 877     can_prune_locals = false;  // do not prune locals
 878     stack_slots_not_pruned = 0;
 879   }
 880 
 881   // do not scribble on the input jvms
 882   JVMState* out_jvms = youngest_jvms->clone_deep(C);
 883   call->set_jvms(out_jvms); // Start jvms list for call node
 884 
 885   // For a known set of bytecodes, the interpreter should reexecute them if
 886   // deoptimization happens. We set the reexecute state for them here
 887   if (out_jvms->is_reexecute_undefined() && //don't change if already specified
 888       should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
 889     out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
 890   }
 891 
 892   // Presize the call:
 893   DEBUG_ONLY(uint non_debug_edges = call->req());
 894   call->add_req_batch(top(), youngest_jvms->debug_depth());
 895   assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
 896 
 897   // Set up edges so that the call looks like this:
 898   //  Call [state:] ctl io mem fptr retadr
 899   //       [parms:] parm0 ... parmN
 900   //       [root:]  loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 901   //    [...mid:]   loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
 902   //       [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
 903   // Note that caller debug info precedes callee debug info.
 904 
 905   // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
 906   uint debug_ptr = call->req();
 907 
 908   // Loop over the map input edges associated with jvms, add them
 909   // to the call node, & reset all offsets to match call node array.
 910   for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) {
 911     uint debug_end   = debug_ptr;
 912     uint debug_start = debug_ptr - in_jvms->debug_size();
 913     debug_ptr = debug_start;  // back up the ptr
 914 
 915     uint p = debug_start;  // walks forward in [debug_start, debug_end)
 916     uint j, k, l;
 917     SafePointNode* in_map = in_jvms->map();
 918     out_jvms->set_map(call);
 919 
 920     if (can_prune_locals) {
 921       assert(in_jvms->method() == out_jvms->method(), "sanity");
 922       // If the current throw can reach an exception handler in this JVMS,
 923       // then we must keep everything live that can reach that handler.
 924       // As a quick and dirty approximation, we look for any handlers at all.
 925       if (in_jvms->method()->has_exception_handlers()) {
 926         can_prune_locals = false;
 927       }
 928     }
 929 
 930     // Add the Locals
 931     k = in_jvms->locoff();
 932     l = in_jvms->loc_size();
 933     out_jvms->set_locoff(p);
 934     if (!can_prune_locals) {
 935       for (j = 0; j < l; j++)
 936         call->set_req(p++, in_map->in(k+j));
 937     } else {
 938       p += l;  // already set to top above by add_req_batch
 939     }
 940 
 941     // Add the Expression Stack
 942     k = in_jvms->stkoff();
 943     l = in_jvms->sp();
 944     out_jvms->set_stkoff(p);
 945     if (!can_prune_locals) {
 946       for (j = 0; j < l; j++)
 947         call->set_req(p++, in_map->in(k+j));
 948     } else if (can_prune_locals && stack_slots_not_pruned != 0) {
 949       // Divide stack into {S0,...,S1}, where S0 is set to top.
 950       uint s1 = stack_slots_not_pruned;
 951       stack_slots_not_pruned = 0;  // for next iteration
 952       if (s1 > l)  s1 = l;
 953       uint s0 = l - s1;
 954       p += s0;  // skip the tops preinstalled by add_req_batch
 955       for (j = s0; j < l; j++)
 956         call->set_req(p++, in_map->in(k+j));
 957     } else {
 958       p += l;  // already set to top above by add_req_batch
 959     }
 960 
 961     // Add the Monitors
 962     k = in_jvms->monoff();
 963     l = in_jvms->mon_size();
 964     out_jvms->set_monoff(p);
 965     for (j = 0; j < l; j++)
 966       call->set_req(p++, in_map->in(k+j));
 967 
 968     // Copy any scalar object fields.
 969     k = in_jvms->scloff();
 970     l = in_jvms->scl_size();
 971     out_jvms->set_scloff(p);
 972     for (j = 0; j < l; j++)
 973       call->set_req(p++, in_map->in(k+j));
 974 
 975     // Finish the new jvms.
 976     out_jvms->set_endoff(p);
 977 
 978     assert(out_jvms->endoff()     == debug_end,             "fill ptr must match");
 979     assert(out_jvms->depth()      == in_jvms->depth(),      "depth must match");
 980     assert(out_jvms->loc_size()   == in_jvms->loc_size(),   "size must match");
 981     assert(out_jvms->mon_size()   == in_jvms->mon_size(),   "size must match");
 982     assert(out_jvms->scl_size()   == in_jvms->scl_size(),   "size must match");
 983     assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
 984 
 985     // Update the two tail pointers in parallel.
 986     out_jvms = out_jvms->caller();
 987     in_jvms  = in_jvms->caller();
 988   }
 989 
 990   assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
 991 
 992   // Test the correctness of JVMState::debug_xxx accessors:
 993   assert(call->jvms()->debug_start() == non_debug_edges, "");
 994   assert(call->jvms()->debug_end()   == call->req(), "");
 995   assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
 996 }
 997 
 998 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
 999   Bytecodes::Code code = java_bc();
1000   if (code == Bytecodes::_wide) {
1001     code = method()->java_code_at_bci(bci() + 1);
1002   }
1003 
1004   BasicType rtype = T_ILLEGAL;
1005   int       rsize = 0;
1006 
1007   if (code != Bytecodes::_illegal) {
1008     depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1009     rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1010     if (rtype < T_CONFLICT)
1011       rsize = type2size[rtype];
1012   }
1013 
1014   switch (code) {
1015   case Bytecodes::_illegal:
1016     return false;
1017 
1018   case Bytecodes::_ldc:
1019   case Bytecodes::_ldc_w:
1020   case Bytecodes::_ldc2_w:
1021     inputs = 0;
1022     break;
1023 
1024   case Bytecodes::_dup:         inputs = 1;  break;
1025   case Bytecodes::_dup_x1:      inputs = 2;  break;
1026   case Bytecodes::_dup_x2:      inputs = 3;  break;
1027   case Bytecodes::_dup2:        inputs = 2;  break;
1028   case Bytecodes::_dup2_x1:     inputs = 3;  break;
1029   case Bytecodes::_dup2_x2:     inputs = 4;  break;
1030   case Bytecodes::_swap:        inputs = 2;  break;
1031   case Bytecodes::_arraylength: inputs = 1;  break;
1032 
1033   case Bytecodes::_getstatic:
1034   case Bytecodes::_putstatic:
1035   case Bytecodes::_getfield:
1036   case Bytecodes::_putfield:
1037     {
1038       bool ignored_will_link;
1039       ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1040       int      size  = field->type()->size();
1041       bool is_get = (depth >= 0), is_static = (depth & 1);
1042       inputs = (is_static ? 0 : 1);
1043       if (is_get) {
1044         depth = size - inputs;
1045       } else {
1046         inputs += size;        // putxxx pops the value from the stack
1047         depth = - inputs;
1048       }
1049     }
1050     break;
1051 
1052   case Bytecodes::_invokevirtual:
1053   case Bytecodes::_invokespecial:
1054   case Bytecodes::_invokestatic:
1055   case Bytecodes::_invokedynamic:
1056   case Bytecodes::_invokeinterface:
1057     {
1058       bool ignored_will_link;
1059       ciSignature* declared_signature = NULL;
1060       ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1061       assert(declared_signature != NULL, "cannot be null");
1062       inputs   = declared_signature->arg_size_for_bc(code);
1063       int size = declared_signature->return_type()->size();
1064       depth = size - inputs;
1065     }
1066     break;
1067 
1068   case Bytecodes::_multianewarray:
1069     {
1070       ciBytecodeStream iter(method());
1071       iter.reset_to_bci(bci());
1072       iter.next();
1073       inputs = iter.get_dimensions();
1074       assert(rsize == 1, "");
1075       depth = rsize - inputs;
1076     }
1077     break;
1078 
1079   case Bytecodes::_ireturn:
1080   case Bytecodes::_lreturn:
1081   case Bytecodes::_freturn:
1082   case Bytecodes::_dreturn:
1083   case Bytecodes::_areturn:
1084     assert(rsize == -depth, "");
1085     inputs = rsize;
1086     break;
1087 
1088   case Bytecodes::_jsr:
1089   case Bytecodes::_jsr_w:
1090     inputs = 0;
1091     depth  = 1;                  // S.B. depth=1, not zero
1092     break;
1093 
1094   default:
1095     // bytecode produces a typed result
1096     inputs = rsize - depth;
1097     assert(inputs >= 0, "");
1098     break;
1099   }
1100 
1101 #ifdef ASSERT
1102   // spot check
1103   int outputs = depth + inputs;
1104   assert(outputs >= 0, "sanity");
1105   switch (code) {
1106   case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1107   case Bytecodes::_athrow:    assert(inputs == 1 && outputs == 0, ""); break;
1108   case Bytecodes::_aload_0:   assert(inputs == 0 && outputs == 1, ""); break;
1109   case Bytecodes::_return:    assert(inputs == 0 && outputs == 0, ""); break;
1110   case Bytecodes::_drem:      assert(inputs == 4 && outputs == 2, ""); break;
1111   default:                    break;
1112   }
1113 #endif //ASSERT
1114 
1115   return true;
1116 }
1117 
1118 
1119 
1120 //------------------------------basic_plus_adr---------------------------------
1121 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1122   // short-circuit a common case
1123   if (offset == intcon(0))  return ptr;
1124   return _gvn.transform( new AddPNode(base, ptr, offset) );
1125 }
1126 
1127 Node* GraphKit::ConvI2L(Node* offset) {
1128   // short-circuit a common case
1129   jint offset_con = find_int_con(offset, Type::OffsetBot);
1130   if (offset_con != Type::OffsetBot) {
1131     return longcon((jlong) offset_con);
1132   }
1133   return _gvn.transform( new ConvI2LNode(offset));
1134 }
1135 
1136 Node* GraphKit::ConvI2UL(Node* offset) {
1137   juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1138   if (offset_con != (juint) Type::OffsetBot) {
1139     return longcon((julong) offset_con);
1140   }
1141   Node* conv = _gvn.transform( new ConvI2LNode(offset));
1142   Node* mask = _gvn.transform(ConLNode::make((julong) max_juint));
1143   return _gvn.transform( new AndLNode(conv, mask) );
1144 }
1145 
1146 Node* GraphKit::ConvL2I(Node* offset) {
1147   // short-circuit a common case
1148   jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1149   if (offset_con != (jlong)Type::OffsetBot) {
1150     return intcon((int) offset_con);
1151   }
1152   return _gvn.transform( new ConvL2INode(offset));
1153 }
1154 
1155 //-------------------------load_object_klass-----------------------------------
1156 Node* GraphKit::load_object_klass(Node* obj) {
1157   // Special-case a fresh allocation to avoid building nodes:
1158   Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1159   if (akls != NULL)  return akls;
1160   Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1161   return _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), k_adr, TypeInstPtr::KLASS));
1162 }
1163 
1164 //-------------------------load_array_length-----------------------------------
1165 Node* GraphKit::load_array_length(Node* array) {
1166   // Special-case a fresh allocation to avoid building nodes:
1167   AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn);
1168   Node *alen;
1169   if (alloc == NULL) {
1170     Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1171     alen = _gvn.transform( new LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1172   } else {
1173     alen = alloc->Ideal_length();
1174     Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn);
1175     if (ccast != alen) {
1176       alen = _gvn.transform(ccast);
1177     }
1178   }
1179   return alen;
1180 }
1181 
1182 //------------------------------do_null_check----------------------------------
1183 // Helper function to do a NULL pointer check.  Returned value is
1184 // the incoming address with NULL casted away.  You are allowed to use the
1185 // not-null value only if you are control dependent on the test.
1186 #ifndef PRODUCT
1187 extern int explicit_null_checks_inserted,
1188            explicit_null_checks_elided;
1189 #endif
1190 Node* GraphKit::null_check_common(Node* value, BasicType type,
1191                                   // optional arguments for variations:
1192                                   bool assert_null,
1193                                   Node* *null_control,
1194                                   bool speculative) {
1195   assert(!assert_null || null_control == NULL, "not both at once");
1196   if (stopped())  return top();
1197   NOT_PRODUCT(explicit_null_checks_inserted++);
1198 
1199   // Construct NULL check
1200   Node *chk = NULL;
1201   switch(type) {
1202     case T_LONG   : chk = new CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1203     case T_INT    : chk = new CmpINode(value, _gvn.intcon(0)); break;
1204     case T_ARRAY  : // fall through
1205       type = T_OBJECT;  // simplify further tests
1206     case T_OBJECT : {
1207       const Type *t = _gvn.type( value );
1208 
1209       const TypeOopPtr* tp = t->isa_oopptr();
1210       if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded()
1211           // Only for do_null_check, not any of its siblings:
1212           && !assert_null && null_control == NULL) {
1213         // Usually, any field access or invocation on an unloaded oop type
1214         // will simply fail to link, since the statically linked class is
1215         // likely also to be unloaded.  However, in -Xcomp mode, sometimes
1216         // the static class is loaded but the sharper oop type is not.
1217         // Rather than checking for this obscure case in lots of places,
1218         // we simply observe that a null check on an unloaded class
1219         // will always be followed by a nonsense operation, so we
1220         // can just issue the uncommon trap here.
1221         // Our access to the unloaded class will only be correct
1222         // after it has been loaded and initialized, which requires
1223         // a trip through the interpreter.
1224 #ifndef PRODUCT
1225         if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); }
1226 #endif
1227         uncommon_trap(Deoptimization::Reason_unloaded,
1228                       Deoptimization::Action_reinterpret,
1229                       tp->klass(), "!loaded");
1230         return top();
1231       }
1232 
1233       if (assert_null) {
1234         // See if the type is contained in NULL_PTR.
1235         // If so, then the value is already null.
1236         if (t->higher_equal(TypePtr::NULL_PTR)) {
1237           NOT_PRODUCT(explicit_null_checks_elided++);
1238           return value;           // Elided null assert quickly!
1239         }
1240       } else {
1241         // See if mixing in the NULL pointer changes type.
1242         // If so, then the NULL pointer was not allowed in the original
1243         // type.  In other words, "value" was not-null.
1244         if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1245           // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1246           NOT_PRODUCT(explicit_null_checks_elided++);
1247           return value;           // Elided null check quickly!
1248         }
1249       }
1250       chk = new CmpPNode( value, null() );
1251       break;
1252     }
1253 
1254     default:
1255       fatal("unexpected type: %s", type2name(type));
1256   }
1257   assert(chk != NULL, "sanity check");
1258   chk = _gvn.transform(chk);
1259 
1260   BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1261   BoolNode *btst = new BoolNode( chk, btest);
1262   Node   *tst = _gvn.transform( btst );
1263 
1264   //-----------
1265   // if peephole optimizations occurred, a prior test existed.
1266   // If a prior test existed, maybe it dominates as we can avoid this test.
1267   if (tst != btst && type == T_OBJECT) {
1268     // At this point we want to scan up the CFG to see if we can
1269     // find an identical test (and so avoid this test altogether).
1270     Node *cfg = control();
1271     int depth = 0;
1272     while( depth < 16 ) {       // Limit search depth for speed
1273       if( cfg->Opcode() == Op_IfTrue &&
1274           cfg->in(0)->in(1) == tst ) {
1275         // Found prior test.  Use "cast_not_null" to construct an identical
1276         // CastPP (and hence hash to) as already exists for the prior test.
1277         // Return that casted value.
1278         if (assert_null) {
1279           replace_in_map(value, null());
1280           return null();  // do not issue the redundant test
1281         }
1282         Node *oldcontrol = control();
1283         set_control(cfg);
1284         Node *res = cast_not_null(value);
1285         set_control(oldcontrol);
1286         NOT_PRODUCT(explicit_null_checks_elided++);
1287         return res;
1288       }
1289       cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1290       if (cfg == NULL)  break;  // Quit at region nodes
1291       depth++;
1292     }
1293   }
1294 
1295   //-----------
1296   // Branch to failure if null
1297   float ok_prob = PROB_MAX;  // a priori estimate:  nulls never happen
1298   Deoptimization::DeoptReason reason;
1299   if (assert_null) {
1300     reason = Deoptimization::reason_null_assert(speculative);
1301   } else if (type == T_OBJECT) {
1302     reason = Deoptimization::reason_null_check(speculative);
1303   } else {
1304     reason = Deoptimization::Reason_div0_check;
1305   }
1306   // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1307   // ciMethodData::has_trap_at will return a conservative -1 if any
1308   // must-be-null assertion has failed.  This could cause performance
1309   // problems for a method after its first do_null_assert failure.
1310   // Consider using 'Reason_class_check' instead?
1311 
1312   // To cause an implicit null check, we set the not-null probability
1313   // to the maximum (PROB_MAX).  For an explicit check the probability
1314   // is set to a smaller value.
1315   if (null_control != NULL || too_many_traps(reason)) {
1316     // probability is less likely
1317     ok_prob =  PROB_LIKELY_MAG(3);
1318   } else if (!assert_null &&
1319              (ImplicitNullCheckThreshold > 0) &&
1320              method() != NULL &&
1321              (method()->method_data()->trap_count(reason)
1322               >= (uint)ImplicitNullCheckThreshold)) {
1323     ok_prob =  PROB_LIKELY_MAG(3);
1324   }
1325 
1326   if (null_control != NULL) {
1327     IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1328     Node* null_true = _gvn.transform( new IfFalseNode(iff));
1329     set_control(      _gvn.transform( new IfTrueNode(iff)));
1330 #ifndef PRODUCT
1331     if (null_true == top()) {
1332       explicit_null_checks_elided++;
1333     }
1334 #endif
1335     (*null_control) = null_true;
1336   } else {
1337     BuildCutout unless(this, tst, ok_prob);
1338     // Check for optimizer eliding test at parse time
1339     if (stopped()) {
1340       // Failure not possible; do not bother making uncommon trap.
1341       NOT_PRODUCT(explicit_null_checks_elided++);
1342     } else if (assert_null) {
1343       uncommon_trap(reason,
1344                     Deoptimization::Action_make_not_entrant,
1345                     NULL, "assert_null");
1346     } else {
1347       replace_in_map(value, zerocon(type));
1348       builtin_throw(reason);
1349     }
1350   }
1351 
1352   // Must throw exception, fall-thru not possible?
1353   if (stopped()) {
1354     return top();               // No result
1355   }
1356 
1357   if (assert_null) {
1358     // Cast obj to null on this path.
1359     replace_in_map(value, zerocon(type));
1360     return zerocon(type);
1361   }
1362 
1363   // Cast obj to not-null on this path, if there is no null_control.
1364   // (If there is a null_control, a non-null value may come back to haunt us.)
1365   if (type == T_OBJECT) {
1366     Node* cast = cast_not_null(value, false);
1367     if (null_control == NULL || (*null_control) == top())
1368       replace_in_map(value, cast);
1369     value = cast;
1370   }
1371 
1372   return value;
1373 }
1374 
1375 
1376 //------------------------------cast_not_null----------------------------------
1377 // Cast obj to not-null on this path
1378 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1379   const Type *t = _gvn.type(obj);
1380   const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1381   // Object is already not-null?
1382   if( t == t_not_null ) return obj;
1383 
1384   Node *cast = new CastPPNode(obj,t_not_null);
1385   cast->init_req(0, control());
1386   cast = _gvn.transform( cast );
1387 
1388   // Scan for instances of 'obj' in the current JVM mapping.
1389   // These instances are known to be not-null after the test.
1390   if (do_replace_in_map)
1391     replace_in_map(obj, cast);
1392 
1393   return cast;                  // Return casted value
1394 }
1395 
1396 // Sometimes in intrinsics, we implicitly know an object is not null
1397 // (there's no actual null check) so we can cast it to not null. In
1398 // the course of optimizations, the input to the cast can become null.
1399 // In that case that data path will die and we need the control path
1400 // to become dead as well to keep the graph consistent. So we have to
1401 // add a check for null for which one branch can't be taken. It uses
1402 // an Opaque4 node that will cause the check to be removed after loop
1403 // opts so the test goes away and the compiled code doesn't execute a
1404 // useless check.
1405 Node* GraphKit::must_be_not_null(Node* value, bool do_replace_in_map) {
1406   Node* chk = _gvn.transform(new CmpPNode(value, null()));
1407   Node *tst = _gvn.transform(new BoolNode(chk, BoolTest::ne));
1408   Node* opaq = _gvn.transform(new Opaque4Node(C, tst, intcon(1)));
1409   IfNode *iff = new IfNode(control(), opaq, PROB_MAX, COUNT_UNKNOWN);
1410   _gvn.set_type(iff, iff->Value(&_gvn));
1411   Node *if_f = _gvn.transform(new IfFalseNode(iff));
1412   Node *frame = _gvn.transform(new ParmNode(C->start(), TypeFunc::FramePtr));
1413   Node *halt = _gvn.transform(new HaltNode(if_f, frame));
1414   C->root()->add_req(halt);
1415   Node *if_t = _gvn.transform(new IfTrueNode(iff));
1416   set_control(if_t);
1417   return cast_not_null(value, do_replace_in_map);
1418 }
1419 
1420 
1421 //--------------------------replace_in_map-------------------------------------
1422 void GraphKit::replace_in_map(Node* old, Node* neww) {
1423   if (old == neww) {
1424     return;
1425   }
1426 
1427   map()->replace_edge(old, neww);
1428 
1429   // Note: This operation potentially replaces any edge
1430   // on the map.  This includes locals, stack, and monitors
1431   // of the current (innermost) JVM state.
1432 
1433   // don't let inconsistent types from profiling escape this
1434   // method
1435 
1436   const Type* told = _gvn.type(old);
1437   const Type* tnew = _gvn.type(neww);
1438 
1439   if (!tnew->higher_equal(told)) {
1440     return;
1441   }
1442 
1443   map()->record_replaced_node(old, neww);
1444 }
1445 
1446 
1447 //=============================================================================
1448 //--------------------------------memory---------------------------------------
1449 Node* GraphKit::memory(uint alias_idx) {
1450   MergeMemNode* mem = merged_memory();
1451   Node* p = mem->memory_at(alias_idx);
1452   _gvn.set_type(p, Type::MEMORY);  // must be mapped
1453   return p;
1454 }
1455 
1456 //-----------------------------reset_memory------------------------------------
1457 Node* GraphKit::reset_memory() {
1458   Node* mem = map()->memory();
1459   // do not use this node for any more parsing!
1460   debug_only( map()->set_memory((Node*)NULL) );
1461   return _gvn.transform( mem );
1462 }
1463 
1464 //------------------------------set_all_memory---------------------------------
1465 void GraphKit::set_all_memory(Node* newmem) {
1466   Node* mergemem = MergeMemNode::make(newmem);
1467   gvn().set_type_bottom(mergemem);
1468   map()->set_memory(mergemem);
1469 }
1470 
1471 //------------------------------set_all_memory_call----------------------------
1472 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1473   Node* newmem = _gvn.transform( new ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1474   set_all_memory(newmem);
1475 }
1476 
1477 //=============================================================================
1478 //
1479 // parser factory methods for MemNodes
1480 //
1481 // These are layered on top of the factory methods in LoadNode and StoreNode,
1482 // and integrate with the parser's memory state and _gvn engine.
1483 //
1484 
1485 // factory methods in "int adr_idx"
1486 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1487                           int adr_idx,
1488                           MemNode::MemOrd mo,
1489                           LoadNode::ControlDependency control_dependency,
1490                           bool require_atomic_access,
1491                           bool unaligned,
1492                           bool mismatched) {
1493   assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1494   const TypePtr* adr_type = NULL; // debug-mode-only argument
1495   debug_only(adr_type = C->get_adr_type(adr_idx));
1496   Node* mem = memory(adr_idx);
1497   Node* ld;
1498   if (require_atomic_access && bt == T_LONG) {
1499     ld = LoadLNode::make_atomic(ctl, mem, adr, adr_type, t, mo, control_dependency, unaligned, mismatched);
1500   } else if (require_atomic_access && bt == T_DOUBLE) {
1501     ld = LoadDNode::make_atomic(ctl, mem, adr, adr_type, t, mo, control_dependency, unaligned, mismatched);
1502   } else {
1503     ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, unaligned, mismatched);
1504   }
1505   ld = _gvn.transform(ld);
1506   if (((bt == T_OBJECT) && C->do_escape_analysis()) || C->eliminate_boxing()) {
1507     // Improve graph before escape analysis and boxing elimination.
1508     record_for_igvn(ld);
1509   }
1510   return ld;
1511 }
1512 
1513 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1514                                 int adr_idx,
1515                                 MemNode::MemOrd mo,
1516                                 bool require_atomic_access,
1517                                 bool unaligned,
1518                                 bool mismatched) {
1519   assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1520   const TypePtr* adr_type = NULL;
1521   debug_only(adr_type = C->get_adr_type(adr_idx));
1522   Node *mem = memory(adr_idx);
1523   Node* st;
1524   if (require_atomic_access && bt == T_LONG) {
1525     st = StoreLNode::make_atomic(ctl, mem, adr, adr_type, val, mo);
1526   } else if (require_atomic_access && bt == T_DOUBLE) {
1527     st = StoreDNode::make_atomic(ctl, mem, adr, adr_type, val, mo);
1528   } else {
1529     st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo);
1530   }
1531   if (unaligned) {
1532     st->as_Store()->set_unaligned_access();
1533   }
1534   if (mismatched) {
1535     st->as_Store()->set_mismatched_access();
1536   }
1537   st = _gvn.transform(st);
1538   set_memory(st, adr_idx);
1539   // Back-to-back stores can only remove intermediate store with DU info
1540   // so push on worklist for optimizer.
1541   if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1542     record_for_igvn(st);
1543 
1544   return st;
1545 }
1546 
1547 
1548 void GraphKit::pre_barrier(bool do_load,
1549                            Node* ctl,
1550                            Node* obj,
1551                            Node* adr,
1552                            uint  adr_idx,
1553                            Node* val,
1554                            const TypeOopPtr* val_type,
1555                            Node* pre_val,
1556                            BasicType bt) {
1557 
1558   BarrierSet* bs = Universe::heap()->barrier_set();
1559   set_control(ctl);
1560   switch (bs->kind()) {
1561     case BarrierSet::G1SATBCTLogging:
1562       g1_write_barrier_pre(do_load, obj, adr, adr_idx, val, val_type, pre_val, bt);
1563       break;
1564 
1565     case BarrierSet::CardTableForRS:
1566     case BarrierSet::CardTableExtension:
1567     case BarrierSet::ModRef:
1568       break;
1569 
1570     default      :
1571       ShouldNotReachHere();
1572 
1573   }
1574 }
1575 
1576 bool GraphKit::can_move_pre_barrier() const {
1577   BarrierSet* bs = Universe::heap()->barrier_set();
1578   switch (bs->kind()) {
1579     case BarrierSet::G1SATBCTLogging:
1580       return true; // Can move it if no safepoint
1581 
1582     case BarrierSet::CardTableForRS:
1583     case BarrierSet::CardTableExtension:
1584     case BarrierSet::ModRef:
1585       return true; // There is no pre-barrier
1586 
1587     default      :
1588       ShouldNotReachHere();
1589   }
1590   return false;
1591 }
1592 
1593 void GraphKit::post_barrier(Node* ctl,
1594                             Node* store,
1595                             Node* obj,
1596                             Node* adr,
1597                             uint  adr_idx,
1598                             Node* val,
1599                             BasicType bt,
1600                             bool use_precise) {
1601   BarrierSet* bs = Universe::heap()->barrier_set();
1602   set_control(ctl);
1603   switch (bs->kind()) {
1604     case BarrierSet::G1SATBCTLogging:
1605       g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise);
1606       break;
1607 
1608     case BarrierSet::CardTableForRS:
1609     case BarrierSet::CardTableExtension:
1610       write_barrier_post(store, obj, adr, adr_idx, val, use_precise);
1611       break;
1612 
1613     case BarrierSet::ModRef:
1614       break;
1615 
1616     default      :
1617       ShouldNotReachHere();
1618 
1619   }
1620 }
1621 
1622 Node* GraphKit::store_oop(Node* ctl,
1623                           Node* obj,
1624                           Node* adr,
1625                           const TypePtr* adr_type,
1626                           Node* val,
1627                           const TypeOopPtr* val_type,
1628                           BasicType bt,
1629                           bool use_precise,
1630                           MemNode::MemOrd mo,
1631                           bool mismatched) {
1632   // Transformation of a value which could be NULL pointer (CastPP #NULL)
1633   // could be delayed during Parse (for example, in adjust_map_after_if()).
1634   // Execute transformation here to avoid barrier generation in such case.
1635   if (_gvn.type(val) == TypePtr::NULL_PTR)
1636     val = _gvn.makecon(TypePtr::NULL_PTR);
1637 
1638   set_control(ctl);
1639   if (stopped()) return top(); // Dead path ?
1640 
1641   assert(bt == T_OBJECT, "sanity");
1642   assert(val != NULL, "not dead path");
1643   uint adr_idx = C->get_alias_index(adr_type);
1644   assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1645 
1646   pre_barrier(true /* do_load */,
1647               control(), obj, adr, adr_idx, val, val_type,
1648               NULL /* pre_val */,
1649               bt);
1650 
1651   Node* store = store_to_memory(control(), adr, val, bt, adr_idx, mo, mismatched);
1652   post_barrier(control(), store, obj, adr, adr_idx, val, bt, use_precise);
1653   return store;
1654 }
1655 
1656 // Could be an array or object we don't know at compile time (unsafe ref.)
1657 Node* GraphKit::store_oop_to_unknown(Node* ctl,
1658                              Node* obj,   // containing obj
1659                              Node* adr,  // actual adress to store val at
1660                              const TypePtr* adr_type,
1661                              Node* val,
1662                              BasicType bt,
1663                              MemNode::MemOrd mo,
1664                              bool mismatched) {
1665   Compile::AliasType* at = C->alias_type(adr_type);
1666   const TypeOopPtr* val_type = NULL;
1667   if (adr_type->isa_instptr()) {
1668     if (at->field() != NULL) {
1669       // known field.  This code is a copy of the do_put_xxx logic.
1670       ciField* field = at->field();
1671       if (!field->type()->is_loaded()) {
1672         val_type = TypeInstPtr::BOTTOM;
1673       } else {
1674         val_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
1675       }
1676     }
1677   } else if (adr_type->isa_aryptr()) {
1678     val_type = adr_type->is_aryptr()->elem()->make_oopptr();
1679   }
1680   if (val_type == NULL) {
1681     val_type = TypeInstPtr::BOTTOM;
1682   }
1683   return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true, mo, mismatched);
1684 }
1685 
1686 
1687 //-------------------------array_element_address-------------------------
1688 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1689                                       const TypeInt* sizetype, Node* ctrl) {
1690   uint shift  = exact_log2(type2aelembytes(elembt));
1691   uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1692 
1693   // short-circuit a common case (saves lots of confusing waste motion)
1694   jint idx_con = find_int_con(idx, -1);
1695   if (idx_con >= 0) {
1696     intptr_t offset = header + ((intptr_t)idx_con << shift);
1697     return basic_plus_adr(ary, offset);
1698   }
1699 
1700   // must be correct type for alignment purposes
1701   Node* base  = basic_plus_adr(ary, header);
1702   idx = Compile::conv_I2X_index(&_gvn, idx, sizetype, ctrl);
1703   Node* scale = _gvn.transform( new LShiftXNode(idx, intcon(shift)) );
1704   return basic_plus_adr(ary, base, scale);
1705 }
1706 
1707 //-------------------------load_array_element-------------------------
1708 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) {
1709   const Type* elemtype = arytype->elem();
1710   BasicType elembt = elemtype->array_element_basic_type();
1711   Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1712   if (elembt == T_NARROWOOP) {
1713     elembt = T_OBJECT; // To satisfy switch in LoadNode::make()
1714   }
1715   Node* ld = make_load(ctl, adr, elemtype, elembt, arytype, MemNode::unordered);
1716   return ld;
1717 }
1718 
1719 //-------------------------set_arguments_for_java_call-------------------------
1720 // Arguments (pre-popped from the stack) are taken from the JVMS.
1721 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1722   // Add the call arguments:
1723   uint nargs = call->method()->arg_size();
1724   for (uint i = 0; i < nargs; i++) {
1725     Node* arg = argument(i);
1726     call->init_req(i + TypeFunc::Parms, arg);
1727   }
1728 }
1729 
1730 //---------------------------set_edges_for_java_call---------------------------
1731 // Connect a newly created call into the current JVMS.
1732 // A return value node (if any) is returned from set_edges_for_java_call.
1733 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1734 
1735   // Add the predefined inputs:
1736   call->init_req( TypeFunc::Control, control() );
1737   call->init_req( TypeFunc::I_O    , i_o() );
1738   call->init_req( TypeFunc::Memory , reset_memory() );
1739   call->init_req( TypeFunc::FramePtr, frameptr() );
1740   call->init_req( TypeFunc::ReturnAdr, top() );
1741 
1742   add_safepoint_edges(call, must_throw);
1743 
1744   Node* xcall = _gvn.transform(call);
1745 
1746   if (xcall == top()) {
1747     set_control(top());
1748     return;
1749   }
1750   assert(xcall == call, "call identity is stable");
1751 
1752   // Re-use the current map to produce the result.
1753 
1754   set_control(_gvn.transform(new ProjNode(call, TypeFunc::Control)));
1755   set_i_o(    _gvn.transform(new ProjNode(call, TypeFunc::I_O    , separate_io_proj)));
1756   set_all_memory_call(xcall, separate_io_proj);
1757 
1758   //return xcall;   // no need, caller already has it
1759 }
1760 
1761 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) {
1762   if (stopped())  return top();  // maybe the call folded up?
1763 
1764   // Capture the return value, if any.
1765   Node* ret;
1766   if (call->method() == NULL ||
1767       call->method()->return_type()->basic_type() == T_VOID)
1768         ret = top();
1769   else  ret = _gvn.transform(new ProjNode(call, TypeFunc::Parms));
1770 
1771   // Note:  Since any out-of-line call can produce an exception,
1772   // we always insert an I_O projection from the call into the result.
1773 
1774   make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj);
1775 
1776   if (separate_io_proj) {
1777     // The caller requested separate projections be used by the fall
1778     // through and exceptional paths, so replace the projections for
1779     // the fall through path.
1780     set_i_o(_gvn.transform( new ProjNode(call, TypeFunc::I_O) ));
1781     set_all_memory(_gvn.transform( new ProjNode(call, TypeFunc::Memory) ));
1782   }
1783   return ret;
1784 }
1785 
1786 //--------------------set_predefined_input_for_runtime_call--------------------
1787 // Reading and setting the memory state is way conservative here.
1788 // The real problem is that I am not doing real Type analysis on memory,
1789 // so I cannot distinguish card mark stores from other stores.  Across a GC
1790 // point the Store Barrier and the card mark memory has to agree.  I cannot
1791 // have a card mark store and its barrier split across the GC point from
1792 // either above or below.  Here I get that to happen by reading ALL of memory.
1793 // A better answer would be to separate out card marks from other memory.
1794 // For now, return the input memory state, so that it can be reused
1795 // after the call, if this call has restricted memory effects.
1796 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) {
1797   // Set fixed predefined input arguments
1798   Node* memory = reset_memory();
1799   call->init_req( TypeFunc::Control,   control()  );
1800   call->init_req( TypeFunc::I_O,       top()      ); // does no i/o
1801   call->init_req( TypeFunc::Memory,    memory     ); // may gc ptrs
1802   call->init_req( TypeFunc::FramePtr,  frameptr() );
1803   call->init_req( TypeFunc::ReturnAdr, top()      );
1804   return memory;
1805 }
1806 
1807 //-------------------set_predefined_output_for_runtime_call--------------------
1808 // Set control and memory (not i_o) from the call.
1809 // If keep_mem is not NULL, use it for the output state,
1810 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1811 // If hook_mem is NULL, this call produces no memory effects at all.
1812 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1813 // then only that memory slice is taken from the call.
1814 // In the last case, we must put an appropriate memory barrier before
1815 // the call, so as to create the correct anti-dependencies on loads
1816 // preceding the call.
1817 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1818                                                       Node* keep_mem,
1819                                                       const TypePtr* hook_mem) {
1820   // no i/o
1821   set_control(_gvn.transform( new ProjNode(call,TypeFunc::Control) ));
1822   if (keep_mem) {
1823     // First clone the existing memory state
1824     set_all_memory(keep_mem);
1825     if (hook_mem != NULL) {
1826       // Make memory for the call
1827       Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
1828       // Set the RawPtr memory state only.  This covers all the heap top/GC stuff
1829       // We also use hook_mem to extract specific effects from arraycopy stubs.
1830       set_memory(mem, hook_mem);
1831     }
1832     // ...else the call has NO memory effects.
1833 
1834     // Make sure the call advertises its memory effects precisely.
1835     // This lets us build accurate anti-dependences in gcm.cpp.
1836     assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1837            "call node must be constructed correctly");
1838   } else {
1839     assert(hook_mem == NULL, "");
1840     // This is not a "slow path" call; all memory comes from the call.
1841     set_all_memory_call(call);
1842   }
1843 }
1844 
1845 
1846 // Replace the call with the current state of the kit.
1847 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes) {
1848   JVMState* ejvms = NULL;
1849   if (has_exceptions()) {
1850     ejvms = transfer_exceptions_into_jvms();
1851   }
1852 
1853   ReplacedNodes replaced_nodes = map()->replaced_nodes();
1854   ReplacedNodes replaced_nodes_exception;
1855   Node* ex_ctl = top();
1856 
1857   SafePointNode* final_state = stop();
1858 
1859   // Find all the needed outputs of this call
1860   CallProjections callprojs;
1861   call->extract_projections(&callprojs, true);
1862 
1863   Node* init_mem = call->in(TypeFunc::Memory);
1864   Node* final_mem = final_state->in(TypeFunc::Memory);
1865   Node* final_ctl = final_state->in(TypeFunc::Control);
1866   Node* final_io = final_state->in(TypeFunc::I_O);
1867 
1868   // Replace all the old call edges with the edges from the inlining result
1869   if (callprojs.fallthrough_catchproj != NULL) {
1870     C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
1871   }
1872   if (callprojs.fallthrough_memproj != NULL) {
1873     if (final_mem->is_MergeMem()) {
1874       // Parser's exits MergeMem was not transformed but may be optimized
1875       final_mem = _gvn.transform(final_mem);
1876     }
1877     C->gvn_replace_by(callprojs.fallthrough_memproj,   final_mem);
1878   }
1879   if (callprojs.fallthrough_ioproj != NULL) {
1880     C->gvn_replace_by(callprojs.fallthrough_ioproj,    final_io);
1881   }
1882 
1883   // Replace the result with the new result if it exists and is used
1884   if (callprojs.resproj != NULL && result != NULL) {
1885     C->gvn_replace_by(callprojs.resproj, result);
1886   }
1887 
1888   if (ejvms == NULL) {
1889     // No exception edges to simply kill off those paths
1890     if (callprojs.catchall_catchproj != NULL) {
1891       C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1892     }
1893     if (callprojs.catchall_memproj != NULL) {
1894       C->gvn_replace_by(callprojs.catchall_memproj,   C->top());
1895     }
1896     if (callprojs.catchall_ioproj != NULL) {
1897       C->gvn_replace_by(callprojs.catchall_ioproj,    C->top());
1898     }
1899     // Replace the old exception object with top
1900     if (callprojs.exobj != NULL) {
1901       C->gvn_replace_by(callprojs.exobj, C->top());
1902     }
1903   } else {
1904     GraphKit ekit(ejvms);
1905 
1906     // Load my combined exception state into the kit, with all phis transformed:
1907     SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1908     replaced_nodes_exception = ex_map->replaced_nodes();
1909 
1910     Node* ex_oop = ekit.use_exception_state(ex_map);
1911 
1912     if (callprojs.catchall_catchproj != NULL) {
1913       C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1914       ex_ctl = ekit.control();
1915     }
1916     if (callprojs.catchall_memproj != NULL) {
1917       C->gvn_replace_by(callprojs.catchall_memproj,   ekit.reset_memory());
1918     }
1919     if (callprojs.catchall_ioproj != NULL) {
1920       C->gvn_replace_by(callprojs.catchall_ioproj,    ekit.i_o());
1921     }
1922 
1923     // Replace the old exception object with the newly created one
1924     if (callprojs.exobj != NULL) {
1925       C->gvn_replace_by(callprojs.exobj, ex_oop);
1926     }
1927   }
1928 
1929   // Disconnect the call from the graph
1930   call->disconnect_inputs(NULL, C);
1931   C->gvn_replace_by(call, C->top());
1932 
1933   // Clean up any MergeMems that feed other MergeMems since the
1934   // optimizer doesn't like that.
1935   if (final_mem->is_MergeMem()) {
1936     Node_List wl;
1937     for (SimpleDUIterator i(final_mem); i.has_next(); i.next()) {
1938       Node* m = i.get();
1939       if (m->is_MergeMem() && !wl.contains(m)) {
1940         wl.push(m);
1941       }
1942     }
1943     while (wl.size()  > 0) {
1944       _gvn.transform(wl.pop());
1945     }
1946   }
1947 
1948   if (callprojs.fallthrough_catchproj != NULL && !final_ctl->is_top() && do_replaced_nodes) {
1949     replaced_nodes.apply(C, final_ctl);
1950   }
1951   if (!ex_ctl->is_top() && do_replaced_nodes) {
1952     replaced_nodes_exception.apply(C, ex_ctl);
1953   }
1954 }
1955 
1956 
1957 //------------------------------increment_counter------------------------------
1958 // for statistics: increment a VM counter by 1
1959 
1960 void GraphKit::increment_counter(address counter_addr) {
1961   Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
1962   increment_counter(adr1);
1963 }
1964 
1965 void GraphKit::increment_counter(Node* counter_addr) {
1966   int adr_type = Compile::AliasIdxRaw;
1967   Node* ctrl = control();
1968   Node* cnt  = make_load(ctrl, counter_addr, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
1969   Node* incr = _gvn.transform(new AddINode(cnt, _gvn.intcon(1)));
1970   store_to_memory(ctrl, counter_addr, incr, T_INT, adr_type, MemNode::unordered);
1971 }
1972 
1973 
1974 //------------------------------uncommon_trap----------------------------------
1975 // Bail out to the interpreter in mid-method.  Implemented by calling the
1976 // uncommon_trap blob.  This helper function inserts a runtime call with the
1977 // right debug info.
1978 void GraphKit::uncommon_trap(int trap_request,
1979                              ciKlass* klass, const char* comment,
1980                              bool must_throw,
1981                              bool keep_exact_action) {
1982   if (failing())  stop();
1983   if (stopped())  return; // trap reachable?
1984 
1985   // Note:  If ProfileTraps is true, and if a deopt. actually
1986   // occurs here, the runtime will make sure an MDO exists.  There is
1987   // no need to call method()->ensure_method_data() at this point.
1988 
1989   // Set the stack pointer to the right value for reexecution:
1990   set_sp(reexecute_sp());
1991 
1992 #ifdef ASSERT
1993   if (!must_throw) {
1994     // Make sure the stack has at least enough depth to execute
1995     // the current bytecode.
1996     int inputs, ignored_depth;
1997     if (compute_stack_effects(inputs, ignored_depth)) {
1998       assert(sp() >= inputs, "must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
1999              Bytecodes::name(java_bc()), sp(), inputs);
2000     }
2001   }
2002 #endif
2003 
2004   Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
2005   Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
2006 
2007   switch (action) {
2008   case Deoptimization::Action_maybe_recompile:
2009   case Deoptimization::Action_reinterpret:
2010     // Temporary fix for 6529811 to allow virtual calls to be sure they
2011     // get the chance to go from mono->bi->mega
2012     if (!keep_exact_action &&
2013         Deoptimization::trap_request_index(trap_request) < 0 &&
2014         too_many_recompiles(reason)) {
2015       // This BCI is causing too many recompilations.
2016       if (C->log() != NULL) {
2017         C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'",
2018                 Deoptimization::trap_reason_name(reason),
2019                 Deoptimization::trap_action_name(action));
2020       }
2021       action = Deoptimization::Action_none;
2022       trap_request = Deoptimization::make_trap_request(reason, action);
2023     } else {
2024       C->set_trap_can_recompile(true);
2025     }
2026     break;
2027   case Deoptimization::Action_make_not_entrant:
2028     C->set_trap_can_recompile(true);
2029     break;
2030   case Deoptimization::Action_none:
2031   case Deoptimization::Action_make_not_compilable:
2032     break;
2033   default:
2034 #ifdef ASSERT
2035     fatal("unknown action %d: %s", action, Deoptimization::trap_action_name(action));
2036 #endif
2037     break;
2038   }
2039 
2040   if (TraceOptoParse) {
2041     char buf[100];
2042     tty->print_cr("Uncommon trap %s at bci:%d",
2043                   Deoptimization::format_trap_request(buf, sizeof(buf),
2044                                                       trap_request), bci());
2045   }
2046 
2047   CompileLog* log = C->log();
2048   if (log != NULL) {
2049     int kid = (klass == NULL)? -1: log->identify(klass);
2050     log->begin_elem("uncommon_trap bci='%d'", bci());
2051     char buf[100];
2052     log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2053                                                           trap_request));
2054     if (kid >= 0)         log->print(" klass='%d'", kid);
2055     if (comment != NULL)  log->print(" comment='%s'", comment);
2056     log->end_elem();
2057   }
2058 
2059   // Make sure any guarding test views this path as very unlikely
2060   Node *i0 = control()->in(0);
2061   if (i0 != NULL && i0->is_If()) {        // Found a guarding if test?
2062     IfNode *iff = i0->as_If();
2063     float f = iff->_prob;   // Get prob
2064     if (control()->Opcode() == Op_IfTrue) {
2065       if (f > PROB_UNLIKELY_MAG(4))
2066         iff->_prob = PROB_MIN;
2067     } else {
2068       if (f < PROB_LIKELY_MAG(4))
2069         iff->_prob = PROB_MAX;
2070     }
2071   }
2072 
2073   // Clear out dead values from the debug info.
2074   kill_dead_locals();
2075 
2076   // Now insert the uncommon trap subroutine call
2077   address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point();
2078   const TypePtr* no_memory_effects = NULL;
2079   // Pass the index of the class to be loaded
2080   Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2081                                  (must_throw ? RC_MUST_THROW : 0),
2082                                  OptoRuntime::uncommon_trap_Type(),
2083                                  call_addr, "uncommon_trap", no_memory_effects,
2084                                  intcon(trap_request));
2085   assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2086          "must extract request correctly from the graph");
2087   assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2088 
2089   call->set_req(TypeFunc::ReturnAdr, returnadr());
2090   // The debug info is the only real input to this call.
2091 
2092   // Halt-and-catch fire here.  The above call should never return!
2093   HaltNode* halt = new HaltNode(control(), frameptr());
2094   _gvn.set_type_bottom(halt);
2095   root()->add_req(halt);
2096 
2097   stop_and_kill_map();
2098 }
2099 
2100 
2101 //--------------------------just_allocated_object------------------------------
2102 // Report the object that was just allocated.
2103 // It must be the case that there are no intervening safepoints.
2104 // We use this to determine if an object is so "fresh" that
2105 // it does not require card marks.
2106 Node* GraphKit::just_allocated_object(Node* current_control) {
2107   if (C->recent_alloc_ctl() == current_control)
2108     return C->recent_alloc_obj();
2109   return NULL;
2110 }
2111 
2112 
2113 void GraphKit::round_double_arguments(ciMethod* dest_method) {
2114   // (Note:  TypeFunc::make has a cache that makes this fast.)
2115   const TypeFunc* tf    = TypeFunc::make(dest_method);
2116   int             nargs = tf->domain()->cnt() - TypeFunc::Parms;
2117   for (int j = 0; j < nargs; j++) {
2118     const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2119     if( targ->basic_type() == T_DOUBLE ) {
2120       // If any parameters are doubles, they must be rounded before
2121       // the call, dstore_rounding does gvn.transform
2122       Node *arg = argument(j);
2123       arg = dstore_rounding(arg);
2124       set_argument(j, arg);
2125     }
2126   }
2127 }
2128 
2129 /**
2130  * Record profiling data exact_kls for Node n with the type system so
2131  * that it can propagate it (speculation)
2132  *
2133  * @param n          node that the type applies to
2134  * @param exact_kls  type from profiling
2135  * @param maybe_null did profiling see null?
2136  *
2137  * @return           node with improved type
2138  */
2139 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind) {
2140   const Type* current_type = _gvn.type(n);
2141   assert(UseTypeSpeculation, "type speculation must be on");
2142 
2143   const TypePtr* speculative = current_type->speculative();
2144 
2145   // Should the klass from the profile be recorded in the speculative type?
2146   if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2147     const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls);
2148     const TypeOopPtr* xtype = tklass->as_instance_type();
2149     assert(xtype->klass_is_exact(), "Should be exact");
2150     // Any reason to believe n is not null (from this profiling or a previous one)?
2151     assert(ptr_kind != ProfileAlwaysNull, "impossible here");
2152     const TypePtr* ptr = (ptr_kind == ProfileMaybeNull && current_type->speculative_maybe_null()) ? TypePtr::BOTTOM : TypePtr::NOTNULL;
2153     // record the new speculative type's depth
2154     speculative = xtype->cast_to_ptr_type(ptr->ptr())->is_ptr();
2155     speculative = speculative->with_inline_depth(jvms()->depth());
2156   } else if (current_type->would_improve_ptr(ptr_kind)) {
2157     // Profiling report that null was never seen so we can change the
2158     // speculative type to non null ptr.
2159     if (ptr_kind == ProfileAlwaysNull) {
2160       speculative = TypePtr::NULL_PTR;
2161     } else {
2162       assert(ptr_kind == ProfileNeverNull, "nothing else is an improvement");
2163       const TypePtr* ptr = TypePtr::NOTNULL;
2164       if (speculative != NULL) {
2165         speculative = speculative->cast_to_ptr_type(ptr->ptr())->is_ptr();
2166       } else {
2167         speculative = ptr;
2168       }
2169     }
2170   }
2171 
2172   if (speculative != current_type->speculative()) {
2173     // Build a type with a speculative type (what we think we know
2174     // about the type but will need a guard when we use it)
2175     const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2176     // We're changing the type, we need a new CheckCast node to carry
2177     // the new type. The new type depends on the control: what
2178     // profiling tells us is only valid from here as far as we can
2179     // tell.
2180     Node* cast = new CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2181     cast = _gvn.transform(cast);
2182     replace_in_map(n, cast);
2183     n = cast;
2184   }
2185 
2186   return n;
2187 }
2188 
2189 /**
2190  * Record profiling data from receiver profiling at an invoke with the
2191  * type system so that it can propagate it (speculation)
2192  *
2193  * @param n  receiver node
2194  *
2195  * @return   node with improved type
2196  */
2197 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2198   if (!UseTypeSpeculation) {
2199     return n;
2200   }
2201   ciKlass* exact_kls = profile_has_unique_klass();
2202   ProfilePtrKind ptr_kind = ProfileMaybeNull;
2203   if ((java_bc() == Bytecodes::_checkcast ||
2204        java_bc() == Bytecodes::_instanceof ||
2205        java_bc() == Bytecodes::_aastore) &&
2206       method()->method_data()->is_mature()) {
2207     ciProfileData* data = method()->method_data()->bci_to_data(bci());
2208     if (data != NULL) {
2209       if (!data->as_BitData()->null_seen()) {
2210         ptr_kind = ProfileNeverNull;
2211       } else {
2212         assert(data->is_ReceiverTypeData(), "bad profile data type");
2213         ciReceiverTypeData* call = (ciReceiverTypeData*)data->as_ReceiverTypeData();
2214         uint i = 0;
2215         for (; i < call->row_limit(); i++) {
2216           ciKlass* receiver = call->receiver(i);
2217           if (receiver != NULL) {
2218             break;
2219           }
2220         }
2221         ptr_kind = (i == call->row_limit()) ? ProfileAlwaysNull : ProfileMaybeNull;
2222       }
2223     }
2224   }
2225   return record_profile_for_speculation(n, exact_kls, ptr_kind);
2226 }
2227 
2228 /**
2229  * Record profiling data from argument profiling at an invoke with the
2230  * type system so that it can propagate it (speculation)
2231  *
2232  * @param dest_method  target method for the call
2233  * @param bc           what invoke bytecode is this?
2234  */
2235 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2236   if (!UseTypeSpeculation) {
2237     return;
2238   }
2239   const TypeFunc* tf    = TypeFunc::make(dest_method);
2240   int             nargs = tf->domain()->cnt() - TypeFunc::Parms;
2241   int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2242   for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2243     const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2244     if (targ->basic_type() == T_OBJECT || targ->basic_type() == T_ARRAY) {
2245       ProfilePtrKind ptr_kind = ProfileMaybeNull;
2246       ciKlass* better_type = NULL;
2247       if (method()->argument_profiled_type(bci(), i, better_type, ptr_kind)) {
2248         record_profile_for_speculation(argument(j), better_type, ptr_kind);
2249       }
2250       i++;
2251     }
2252   }
2253 }
2254 
2255 /**
2256  * Record profiling data from parameter profiling at an invoke with
2257  * the type system so that it can propagate it (speculation)
2258  */
2259 void GraphKit::record_profiled_parameters_for_speculation() {
2260   if (!UseTypeSpeculation) {
2261     return;
2262   }
2263   for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2264     if (_gvn.type(local(i))->isa_oopptr()) {
2265       ProfilePtrKind ptr_kind = ProfileMaybeNull;
2266       ciKlass* better_type = NULL;
2267       if (method()->parameter_profiled_type(j, better_type, ptr_kind)) {
2268         record_profile_for_speculation(local(i), better_type, ptr_kind);
2269       }
2270       j++;
2271     }
2272   }
2273 }
2274 
2275 /**
2276  * Record profiling data from return value profiling at an invoke with
2277  * the type system so that it can propagate it (speculation)
2278  */
2279 void GraphKit::record_profiled_return_for_speculation() {
2280   if (!UseTypeSpeculation) {
2281     return;
2282   }
2283   ProfilePtrKind ptr_kind = ProfileMaybeNull;
2284   ciKlass* better_type = NULL;
2285   if (method()->return_profiled_type(bci(), better_type, ptr_kind)) {
2286     // If profiling reports a single type for the return value,
2287     // feed it to the type system so it can propagate it as a
2288     // speculative type
2289     record_profile_for_speculation(stack(sp()-1), better_type, ptr_kind);
2290   }
2291 }
2292 
2293 void GraphKit::round_double_result(ciMethod* dest_method) {
2294   // A non-strict method may return a double value which has an extended
2295   // exponent, but this must not be visible in a caller which is 'strict'
2296   // If a strict caller invokes a non-strict callee, round a double result
2297 
2298   BasicType result_type = dest_method->return_type()->basic_type();
2299   assert( method() != NULL, "must have caller context");
2300   if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) {
2301     // Destination method's return value is on top of stack
2302     // dstore_rounding() does gvn.transform
2303     Node *result = pop_pair();
2304     result = dstore_rounding(result);
2305     push_pair(result);
2306   }
2307 }
2308 
2309 // rounding for strict float precision conformance
2310 Node* GraphKit::precision_rounding(Node* n) {
2311   return UseStrictFP && _method->flags().is_strict()
2312     && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding
2313     ? _gvn.transform( new RoundFloatNode(0, n) )
2314     : n;
2315 }
2316 
2317 // rounding for strict double precision conformance
2318 Node* GraphKit::dprecision_rounding(Node *n) {
2319   return UseStrictFP && _method->flags().is_strict()
2320     && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding
2321     ? _gvn.transform( new RoundDoubleNode(0, n) )
2322     : n;
2323 }
2324 
2325 // rounding for non-strict double stores
2326 Node* GraphKit::dstore_rounding(Node* n) {
2327   return Matcher::strict_fp_requires_explicit_rounding
2328     && UseSSE <= 1
2329     ? _gvn.transform( new RoundDoubleNode(0, n) )
2330     : n;
2331 }
2332 
2333 //=============================================================================
2334 // Generate a fast path/slow path idiom.  Graph looks like:
2335 // [foo] indicates that 'foo' is a parameter
2336 //
2337 //              [in]     NULL
2338 //                 \    /
2339 //                  CmpP
2340 //                  Bool ne
2341 //                   If
2342 //                  /  \
2343 //              True    False-<2>
2344 //              / |
2345 //             /  cast_not_null
2346 //           Load  |    |   ^
2347 //        [fast_test]   |   |
2348 // gvn to   opt_test    |   |
2349 //          /    \      |  <1>
2350 //      True     False  |
2351 //        |         \\  |
2352 //   [slow_call]     \[fast_result]
2353 //    Ctl   Val       \      \
2354 //     |               \      \
2355 //    Catch       <1>   \      \
2356 //   /    \        ^     \      \
2357 //  Ex    No_Ex    |      \      \
2358 //  |       \   \  |       \ <2>  \
2359 //  ...      \  [slow_res] |  |    \   [null_result]
2360 //            \         \--+--+---  |  |
2361 //             \           | /    \ | /
2362 //              --------Region     Phi
2363 //
2364 //=============================================================================
2365 // Code is structured as a series of driver functions all called 'do_XXX' that
2366 // call a set of helper functions.  Helper functions first, then drivers.
2367 
2368 //------------------------------null_check_oop---------------------------------
2369 // Null check oop.  Set null-path control into Region in slot 3.
2370 // Make a cast-not-nullness use the other not-null control.  Return cast.
2371 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2372                                bool never_see_null,
2373                                bool safe_for_replace,
2374                                bool speculative) {
2375   // Initial NULL check taken path
2376   (*null_control) = top();
2377   Node* cast = null_check_common(value, T_OBJECT, false, null_control, speculative);
2378 
2379   // Generate uncommon_trap:
2380   if (never_see_null && (*null_control) != top()) {
2381     // If we see an unexpected null at a check-cast we record it and force a
2382     // recompile; the offending check-cast will be compiled to handle NULLs.
2383     // If we see more than one offending BCI, then all checkcasts in the
2384     // method will be compiled to handle NULLs.
2385     PreserveJVMState pjvms(this);
2386     set_control(*null_control);
2387     replace_in_map(value, null());
2388     Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculative);
2389     uncommon_trap(reason,
2390                   Deoptimization::Action_make_not_entrant);
2391     (*null_control) = top();    // NULL path is dead
2392   }
2393   if ((*null_control) == top() && safe_for_replace) {
2394     replace_in_map(value, cast);
2395   }
2396 
2397   // Cast away null-ness on the result
2398   return cast;
2399 }
2400 
2401 //------------------------------opt_iff----------------------------------------
2402 // Optimize the fast-check IfNode.  Set the fast-path region slot 2.
2403 // Return slow-path control.
2404 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2405   IfNode *opt_iff = _gvn.transform(iff)->as_If();
2406 
2407   // Fast path taken; set region slot 2
2408   Node *fast_taken = _gvn.transform( new IfFalseNode(opt_iff) );
2409   region->init_req(2,fast_taken); // Capture fast-control
2410 
2411   // Fast path not-taken, i.e. slow path
2412   Node *slow_taken = _gvn.transform( new IfTrueNode(opt_iff) );
2413   return slow_taken;
2414 }
2415 
2416 //-----------------------------make_runtime_call-------------------------------
2417 Node* GraphKit::make_runtime_call(int flags,
2418                                   const TypeFunc* call_type, address call_addr,
2419                                   const char* call_name,
2420                                   const TypePtr* adr_type,
2421                                   // The following parms are all optional.
2422                                   // The first NULL ends the list.
2423                                   Node* parm0, Node* parm1,
2424                                   Node* parm2, Node* parm3,
2425                                   Node* parm4, Node* parm5,
2426                                   Node* parm6, Node* parm7) {
2427   // Slow-path call
2428   bool is_leaf = !(flags & RC_NO_LEAF);
2429   bool has_io  = (!is_leaf && !(flags & RC_NO_IO));
2430   if (call_name == NULL) {
2431     assert(!is_leaf, "must supply name for leaf");
2432     call_name = OptoRuntime::stub_name(call_addr);
2433   }
2434   CallNode* call;
2435   if (!is_leaf) {
2436     call = new CallStaticJavaNode(call_type, call_addr, call_name,
2437                                            bci(), adr_type);
2438   } else if (flags & RC_NO_FP) {
2439     call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2440   } else {
2441     call = new CallLeafNode(call_type, call_addr, call_name, adr_type);
2442   }
2443 
2444   // The following is similar to set_edges_for_java_call,
2445   // except that the memory effects of the call are restricted to AliasIdxRaw.
2446 
2447   // Slow path call has no side-effects, uses few values
2448   bool wide_in  = !(flags & RC_NARROW_MEM);
2449   bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2450 
2451   Node* prev_mem = NULL;
2452   if (wide_in) {
2453     prev_mem = set_predefined_input_for_runtime_call(call);
2454   } else {
2455     assert(!wide_out, "narrow in => narrow out");
2456     Node* narrow_mem = memory(adr_type);
2457     prev_mem = reset_memory();
2458     map()->set_memory(narrow_mem);
2459     set_predefined_input_for_runtime_call(call);
2460   }
2461 
2462   // Hook each parm in order.  Stop looking at the first NULL.
2463   if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0);
2464   if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1);
2465   if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2);
2466   if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3);
2467   if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4);
2468   if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5);
2469   if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6);
2470   if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7);
2471     /* close each nested if ===> */  } } } } } } } }
2472   assert(call->in(call->req()-1) != NULL, "must initialize all parms");
2473 
2474   if (!is_leaf) {
2475     // Non-leaves can block and take safepoints:
2476     add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2477   }
2478   // Non-leaves can throw exceptions:
2479   if (has_io) {
2480     call->set_req(TypeFunc::I_O, i_o());
2481   }
2482 
2483   if (flags & RC_UNCOMMON) {
2484     // Set the count to a tiny probability.  Cf. Estimate_Block_Frequency.
2485     // (An "if" probability corresponds roughly to an unconditional count.
2486     // Sort of.)
2487     call->set_cnt(PROB_UNLIKELY_MAG(4));
2488   }
2489 
2490   Node* c = _gvn.transform(call);
2491   assert(c == call, "cannot disappear");
2492 
2493   if (wide_out) {
2494     // Slow path call has full side-effects.
2495     set_predefined_output_for_runtime_call(call);
2496   } else {
2497     // Slow path call has few side-effects, and/or sets few values.
2498     set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2499   }
2500 
2501   if (has_io) {
2502     set_i_o(_gvn.transform(new ProjNode(call, TypeFunc::I_O)));
2503   }
2504   return call;
2505 
2506 }
2507 
2508 //------------------------------merge_memory-----------------------------------
2509 // Merge memory from one path into the current memory state.
2510 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2511   for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2512     Node* old_slice = mms.force_memory();
2513     Node* new_slice = mms.memory2();
2514     if (old_slice != new_slice) {
2515       PhiNode* phi;
2516       if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) {
2517         if (mms.is_empty()) {
2518           // clone base memory Phi's inputs for this memory slice
2519           assert(old_slice == mms.base_memory(), "sanity");
2520           phi = PhiNode::make(region, NULL, Type::MEMORY, mms.adr_type(C));
2521           _gvn.set_type(phi, Type::MEMORY);
2522           for (uint i = 1; i < phi->req(); i++) {
2523             phi->init_req(i, old_slice->in(i));
2524           }
2525         } else {
2526           phi = old_slice->as_Phi(); // Phi was generated already
2527         }
2528       } else {
2529         phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2530         _gvn.set_type(phi, Type::MEMORY);
2531       }
2532       phi->set_req(new_path, new_slice);
2533       mms.set_memory(phi);
2534     }
2535   }
2536 }
2537 
2538 //------------------------------make_slow_call_ex------------------------------
2539 // Make the exception handler hookups for the slow call
2540 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) {
2541   if (stopped())  return;
2542 
2543   // Make a catch node with just two handlers:  fall-through and catch-all
2544   Node* i_o  = _gvn.transform( new ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2545   Node* catc = _gvn.transform( new CatchNode(control(), i_o, 2) );
2546   Node* norm = _gvn.transform( new CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) );
2547   Node* excp = _gvn.transform( new CatchProjNode(catc, CatchProjNode::catch_all_index,    CatchProjNode::no_handler_bci) );
2548 
2549   { PreserveJVMState pjvms(this);
2550     set_control(excp);
2551     set_i_o(i_o);
2552 
2553     if (excp != top()) {
2554       if (deoptimize) {
2555         // Deoptimize if an exception is caught. Don't construct exception state in this case.
2556         uncommon_trap(Deoptimization::Reason_unhandled,
2557                       Deoptimization::Action_none);
2558       } else {
2559         // Create an exception state also.
2560         // Use an exact type if the caller has specified a specific exception.
2561         const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2562         Node*       ex_oop  = new CreateExNode(ex_type, control(), i_o);
2563         add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2564       }
2565     }
2566   }
2567 
2568   // Get the no-exception control from the CatchNode.
2569   set_control(norm);
2570 }
2571 
2572 static IfNode* gen_subtype_check_compare(Node* ctrl, Node* in1, Node* in2, BoolTest::mask test, float p, PhaseGVN* gvn, BasicType bt) {
2573   Node* cmp = NULL;
2574   switch(bt) {
2575   case T_INT: cmp = new CmpINode(in1, in2); break;
2576   case T_ADDRESS: cmp = new CmpPNode(in1, in2); break;
2577   default: fatal("unexpected comparison type %s", type2name(bt));
2578   }
2579   gvn->transform(cmp);
2580   Node* bol = gvn->transform(new BoolNode(cmp, test));
2581   IfNode* iff = new IfNode(ctrl, bol, p, COUNT_UNKNOWN);
2582   gvn->transform(iff);
2583   if (!bol->is_Con()) gvn->record_for_igvn(iff);
2584   return iff;
2585 }
2586 
2587 
2588 //-------------------------------gen_subtype_check-----------------------------
2589 // Generate a subtyping check.  Takes as input the subtype and supertype.
2590 // Returns 2 values: sets the default control() to the true path and returns
2591 // the false path.  Only reads invariant memory; sets no (visible) memory.
2592 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2593 // but that's not exposed to the optimizer.  This call also doesn't take in an
2594 // Object; if you wish to check an Object you need to load the Object's class
2595 // prior to coming here.
2596 Node* Phase::gen_subtype_check(Node* subklass, Node* superklass, Node** ctrl, MergeMemNode* mem, PhaseGVN* gvn) {
2597   Compile* C = gvn->C;
2598 
2599   if ((*ctrl)->is_top()) {
2600     return C->top();
2601   }
2602 
2603   // Fast check for identical types, perhaps identical constants.
2604   // The types can even be identical non-constants, in cases
2605   // involving Array.newInstance, Object.clone, etc.
2606   if (subklass == superklass)
2607     return C->top();             // false path is dead; no test needed.
2608 
2609   if (gvn->type(superklass)->singleton()) {
2610     ciKlass* superk = gvn->type(superklass)->is_klassptr()->klass();
2611     ciKlass* subk   = gvn->type(subklass)->is_klassptr()->klass();
2612 
2613     // In the common case of an exact superklass, try to fold up the
2614     // test before generating code.  You may ask, why not just generate
2615     // the code and then let it fold up?  The answer is that the generated
2616     // code will necessarily include null checks, which do not always
2617     // completely fold away.  If they are also needless, then they turn
2618     // into a performance loss.  Example:
2619     //    Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2620     // Here, the type of 'fa' is often exact, so the store check
2621     // of fa[1]=x will fold up, without testing the nullness of x.
2622     switch (C->static_subtype_check(superk, subk)) {
2623     case Compile::SSC_always_false:
2624       {
2625         Node* always_fail = *ctrl;
2626         *ctrl = gvn->C->top();
2627         return always_fail;
2628       }
2629     case Compile::SSC_always_true:
2630       return C->top();
2631     case Compile::SSC_easy_test:
2632       {
2633         // Just do a direct pointer compare and be done.
2634         IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_STATIC_FREQUENT, gvn, T_ADDRESS);
2635         *ctrl = gvn->transform(new IfTrueNode(iff));
2636         return gvn->transform(new IfFalseNode(iff));
2637       }
2638     case Compile::SSC_full_test:
2639       break;
2640     default:
2641       ShouldNotReachHere();
2642     }
2643   }
2644 
2645   // %%% Possible further optimization:  Even if the superklass is not exact,
2646   // if the subklass is the unique subtype of the superklass, the check
2647   // will always succeed.  We could leave a dependency behind to ensure this.
2648 
2649   // First load the super-klass's check-offset
2650   Node *p1 = gvn->transform(new AddPNode(superklass, superklass, gvn->MakeConX(in_bytes(Klass::super_check_offset_offset()))));
2651   Node* m = mem->memory_at(C->get_alias_index(gvn->type(p1)->is_ptr()));
2652   Node *chk_off = gvn->transform(new LoadINode(NULL, m, p1, gvn->type(p1)->is_ptr(), TypeInt::INT, MemNode::unordered));
2653   int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2654   bool might_be_cache = (gvn->find_int_con(chk_off, cacheoff_con) == cacheoff_con);
2655 
2656   // Load from the sub-klass's super-class display list, or a 1-word cache of
2657   // the secondary superclass list, or a failing value with a sentinel offset
2658   // if the super-klass is an interface or exceptionally deep in the Java
2659   // hierarchy and we have to scan the secondary superclass list the hard way.
2660   // Worst-case type is a little odd: NULL is allowed as a result (usually
2661   // klass loads can never produce a NULL).
2662   Node *chk_off_X = chk_off;
2663 #ifdef _LP64
2664   chk_off_X = gvn->transform(new ConvI2LNode(chk_off_X));
2665 #endif
2666   Node *p2 = gvn->transform(new AddPNode(subklass,subklass,chk_off_X));
2667   // For some types like interfaces the following loadKlass is from a 1-word
2668   // cache which is mutable so can't use immutable memory.  Other
2669   // types load from the super-class display table which is immutable.
2670   m = mem->memory_at(C->get_alias_index(gvn->type(p2)->is_ptr()));
2671   Node *kmem = might_be_cache ? m : C->immutable_memory();
2672   Node *nkls = gvn->transform(LoadKlassNode::make(*gvn, NULL, kmem, p2, gvn->type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL));
2673 
2674   // Compile speed common case: ARE a subtype and we canNOT fail
2675   if( superklass == nkls )
2676     return C->top();             // false path is dead; no test needed.
2677 
2678   // See if we get an immediate positive hit.  Happens roughly 83% of the
2679   // time.  Test to see if the value loaded just previously from the subklass
2680   // is exactly the superklass.
2681   IfNode *iff1 = gen_subtype_check_compare(*ctrl, superklass, nkls, BoolTest::eq, PROB_LIKELY(0.83f), gvn, T_ADDRESS);
2682   Node *iftrue1 = gvn->transform( new IfTrueNode (iff1));
2683   *ctrl = gvn->transform(new IfFalseNode(iff1));
2684 
2685   // Compile speed common case: Check for being deterministic right now.  If
2686   // chk_off is a constant and not equal to cacheoff then we are NOT a
2687   // subklass.  In this case we need exactly the 1 test above and we can
2688   // return those results immediately.
2689   if (!might_be_cache) {
2690     Node* not_subtype_ctrl = *ctrl;
2691     *ctrl = iftrue1; // We need exactly the 1 test above
2692     return not_subtype_ctrl;
2693   }
2694 
2695   // Gather the various success & failures here
2696   RegionNode *r_ok_subtype = new RegionNode(4);
2697   gvn->record_for_igvn(r_ok_subtype);
2698   RegionNode *r_not_subtype = new RegionNode(3);
2699   gvn->record_for_igvn(r_not_subtype);
2700 
2701   r_ok_subtype->init_req(1, iftrue1);
2702 
2703   // Check for immediate negative hit.  Happens roughly 11% of the time (which
2704   // is roughly 63% of the remaining cases).  Test to see if the loaded
2705   // check-offset points into the subklass display list or the 1-element
2706   // cache.  If it points to the display (and NOT the cache) and the display
2707   // missed then it's not a subtype.
2708   Node *cacheoff = gvn->intcon(cacheoff_con);
2709   IfNode *iff2 = gen_subtype_check_compare(*ctrl, chk_off, cacheoff, BoolTest::ne, PROB_LIKELY(0.63f), gvn, T_INT);
2710   r_not_subtype->init_req(1, gvn->transform(new IfTrueNode (iff2)));
2711   *ctrl = gvn->transform(new IfFalseNode(iff2));
2712 
2713   // Check for self.  Very rare to get here, but it is taken 1/3 the time.
2714   // No performance impact (too rare) but allows sharing of secondary arrays
2715   // which has some footprint reduction.
2716   IfNode *iff3 = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_LIKELY(0.36f), gvn, T_ADDRESS);
2717   r_ok_subtype->init_req(2, gvn->transform(new IfTrueNode(iff3)));
2718   *ctrl = gvn->transform(new IfFalseNode(iff3));
2719 
2720   // -- Roads not taken here: --
2721   // We could also have chosen to perform the self-check at the beginning
2722   // of this code sequence, as the assembler does.  This would not pay off
2723   // the same way, since the optimizer, unlike the assembler, can perform
2724   // static type analysis to fold away many successful self-checks.
2725   // Non-foldable self checks work better here in second position, because
2726   // the initial primary superclass check subsumes a self-check for most
2727   // types.  An exception would be a secondary type like array-of-interface,
2728   // which does not appear in its own primary supertype display.
2729   // Finally, we could have chosen to move the self-check into the
2730   // PartialSubtypeCheckNode, and from there out-of-line in a platform
2731   // dependent manner.  But it is worthwhile to have the check here,
2732   // where it can be perhaps be optimized.  The cost in code space is
2733   // small (register compare, branch).
2734 
2735   // Now do a linear scan of the secondary super-klass array.  Again, no real
2736   // performance impact (too rare) but it's gotta be done.
2737   // Since the code is rarely used, there is no penalty for moving it
2738   // out of line, and it can only improve I-cache density.
2739   // The decision to inline or out-of-line this final check is platform
2740   // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2741   Node* psc = gvn->transform(
2742     new PartialSubtypeCheckNode(*ctrl, subklass, superklass));
2743 
2744   IfNode *iff4 = gen_subtype_check_compare(*ctrl, psc, gvn->zerocon(T_OBJECT), BoolTest::ne, PROB_FAIR, gvn, T_ADDRESS);
2745   r_not_subtype->init_req(2, gvn->transform(new IfTrueNode (iff4)));
2746   r_ok_subtype ->init_req(3, gvn->transform(new IfFalseNode(iff4)));
2747 
2748   // Return false path; set default control to true path.
2749   *ctrl = gvn->transform(r_ok_subtype);
2750   return gvn->transform(r_not_subtype);
2751 }
2752 
2753 // Profile-driven exact type check:
2754 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2755                                     float prob,
2756                                     Node* *casted_receiver) {
2757   const TypeKlassPtr* tklass = TypeKlassPtr::make(klass);
2758   Node* recv_klass = load_object_klass(receiver);
2759   Node* want_klass = makecon(tklass);
2760   Node* cmp = _gvn.transform( new CmpPNode(recv_klass, want_klass) );
2761   Node* bol = _gvn.transform( new BoolNode(cmp, BoolTest::eq) );
2762   IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2763   set_control( _gvn.transform( new IfTrueNode (iff) ));
2764   Node* fail = _gvn.transform( new IfFalseNode(iff) );
2765 
2766   const TypeOopPtr* recv_xtype = tklass->as_instance_type();
2767   assert(recv_xtype->klass_is_exact(), "");
2768 
2769   // Subsume downstream occurrences of receiver with a cast to
2770   // recv_xtype, since now we know what the type will be.
2771   Node* cast = new CheckCastPPNode(control(), receiver, recv_xtype);
2772   (*casted_receiver) = _gvn.transform(cast);
2773   // (User must make the replace_in_map call.)
2774 
2775   return fail;
2776 }
2777 
2778 
2779 //------------------------------seems_never_null-------------------------------
2780 // Use null_seen information if it is available from the profile.
2781 // If we see an unexpected null at a type check we record it and force a
2782 // recompile; the offending check will be recompiled to handle NULLs.
2783 // If we see several offending BCIs, then all checks in the
2784 // method will be recompiled.
2785 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data, bool& speculating) {
2786   speculating = !_gvn.type(obj)->speculative_maybe_null();
2787   Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculating);
2788   if (UncommonNullCast               // Cutout for this technique
2789       && obj != null()               // And not the -Xcomp stupid case?
2790       && !too_many_traps(reason)
2791       ) {
2792     if (speculating) {
2793       return true;
2794     }
2795     if (data == NULL)
2796       // Edge case:  no mature data.  Be optimistic here.
2797       return true;
2798     // If the profile has not seen a null, assume it won't happen.
2799     assert(java_bc() == Bytecodes::_checkcast ||
2800            java_bc() == Bytecodes::_instanceof ||
2801            java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
2802     return !data->as_BitData()->null_seen();
2803   }
2804   speculating = false;
2805   return false;
2806 }
2807 
2808 //------------------------maybe_cast_profiled_receiver-------------------------
2809 // If the profile has seen exactly one type, narrow to exactly that type.
2810 // Subsequent type checks will always fold up.
2811 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
2812                                              ciKlass* require_klass,
2813                                              ciKlass* spec_klass,
2814                                              bool safe_for_replace) {
2815   if (!UseTypeProfile || !TypeProfileCasts) return NULL;
2816 
2817   Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != NULL);
2818 
2819   // Make sure we haven't already deoptimized from this tactic.
2820   if (too_many_traps(reason) || too_many_recompiles(reason))
2821     return NULL;
2822 
2823   // (No, this isn't a call, but it's enough like a virtual call
2824   // to use the same ciMethod accessor to get the profile info...)
2825   // If we have a speculative type use it instead of profiling (which
2826   // may not help us)
2827   ciKlass* exact_kls = spec_klass == NULL ? profile_has_unique_klass() : spec_klass;
2828   if (exact_kls != NULL) {// no cast failures here
2829     if (require_klass == NULL ||
2830         C->static_subtype_check(require_klass, exact_kls) == Compile::SSC_always_true) {
2831       // If we narrow the type to match what the type profile sees or
2832       // the speculative type, we can then remove the rest of the
2833       // cast.
2834       // This is a win, even if the exact_kls is very specific,
2835       // because downstream operations, such as method calls,
2836       // will often benefit from the sharper type.
2837       Node* exact_obj = not_null_obj; // will get updated in place...
2838       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
2839                                             &exact_obj);
2840       { PreserveJVMState pjvms(this);
2841         set_control(slow_ctl);
2842         uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile);
2843       }
2844       if (safe_for_replace) {
2845         replace_in_map(not_null_obj, exact_obj);
2846       }
2847       return exact_obj;
2848     }
2849     // assert(ssc == Compile::SSC_always_true)... except maybe the profile lied to us.
2850   }
2851 
2852   return NULL;
2853 }
2854 
2855 /**
2856  * Cast obj to type and emit guard unless we had too many traps here
2857  * already
2858  *
2859  * @param obj       node being casted
2860  * @param type      type to cast the node to
2861  * @param not_null  true if we know node cannot be null
2862  */
2863 Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
2864                                         ciKlass* type,
2865                                         bool not_null) {
2866   if (stopped()) {
2867     return obj;
2868   }
2869 
2870   // type == NULL if profiling tells us this object is always null
2871   if (type != NULL) {
2872     Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
2873     Deoptimization::DeoptReason null_reason = Deoptimization::Reason_speculate_null_check;
2874 
2875     if (!too_many_traps(null_reason) && !too_many_recompiles(null_reason) &&
2876         !too_many_traps(class_reason) &&
2877         !too_many_recompiles(class_reason)) {
2878       Node* not_null_obj = NULL;
2879       // not_null is true if we know the object is not null and
2880       // there's no need for a null check
2881       if (!not_null) {
2882         Node* null_ctl = top();
2883         not_null_obj = null_check_oop(obj, &null_ctl, true, true, true);
2884         assert(null_ctl->is_top(), "no null control here");
2885       } else {
2886         not_null_obj = obj;
2887       }
2888 
2889       Node* exact_obj = not_null_obj;
2890       ciKlass* exact_kls = type;
2891       Node* slow_ctl  = type_check_receiver(exact_obj, exact_kls, 1.0,
2892                                             &exact_obj);
2893       {
2894         PreserveJVMState pjvms(this);
2895         set_control(slow_ctl);
2896         uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile);
2897       }
2898       replace_in_map(not_null_obj, exact_obj);
2899       obj = exact_obj;
2900     }
2901   } else {
2902     if (!too_many_traps(Deoptimization::Reason_null_assert) &&
2903         !too_many_recompiles(Deoptimization::Reason_null_assert)) {
2904       Node* exact_obj = null_assert(obj);
2905       replace_in_map(obj, exact_obj);
2906       obj = exact_obj;
2907     }
2908   }
2909   return obj;
2910 }
2911 
2912 //-------------------------------gen_instanceof--------------------------------
2913 // Generate an instance-of idiom.  Used by both the instance-of bytecode
2914 // and the reflective instance-of call.
2915 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
2916   kill_dead_locals();           // Benefit all the uncommon traps
2917   assert( !stopped(), "dead parse path should be checked in callers" );
2918   assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
2919          "must check for not-null not-dead klass in callers");
2920 
2921   // Make the merge point
2922   enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
2923   RegionNode* region = new RegionNode(PATH_LIMIT);
2924   Node*       phi    = new PhiNode(region, TypeInt::BOOL);
2925   C->set_has_split_ifs(true); // Has chance for split-if optimization
2926 
2927   ciProfileData* data = NULL;
2928   if (java_bc() == Bytecodes::_instanceof) {  // Only for the bytecode
2929     data = method()->method_data()->bci_to_data(bci());
2930   }
2931   bool speculative_not_null = false;
2932   bool never_see_null = (ProfileDynamicTypes  // aggressive use of profile
2933                          && seems_never_null(obj, data, speculative_not_null));
2934 
2935   // Null check; get casted pointer; set region slot 3
2936   Node* null_ctl = top();
2937   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
2938 
2939   // If not_null_obj is dead, only null-path is taken
2940   if (stopped()) {              // Doing instance-of on a NULL?
2941     set_control(null_ctl);
2942     return intcon(0);
2943   }
2944   region->init_req(_null_path, null_ctl);
2945   phi   ->init_req(_null_path, intcon(0)); // Set null path value
2946   if (null_ctl == top()) {
2947     // Do this eagerly, so that pattern matches like is_diamond_phi
2948     // will work even during parsing.
2949     assert(_null_path == PATH_LIMIT-1, "delete last");
2950     region->del_req(_null_path);
2951     phi   ->del_req(_null_path);
2952   }
2953 
2954   // Do we know the type check always succeed?
2955   bool known_statically = false;
2956   if (_gvn.type(superklass)->singleton()) {
2957     ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2958     ciKlass* subk = _gvn.type(obj)->is_oopptr()->klass();
2959     if (subk != NULL && subk->is_loaded()) {
2960       int static_res = C->static_subtype_check(superk, subk);
2961       known_statically = (static_res == Compile::SSC_always_true || static_res == Compile::SSC_always_false);
2962     }
2963   }
2964 
2965   if (!known_statically) {
2966     const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
2967     // We may not have profiling here or it may not help us. If we
2968     // have a speculative type use it to perform an exact cast.
2969     ciKlass* spec_obj_type = obj_type->speculative_type();
2970     if (spec_obj_type != NULL || (ProfileDynamicTypes && data != NULL)) {
2971       Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, NULL, spec_obj_type, safe_for_replace);
2972       if (stopped()) {            // Profile disagrees with this path.
2973         set_control(null_ctl);    // Null is the only remaining possibility.
2974         return intcon(0);
2975       }
2976       if (cast_obj != NULL) {
2977         not_null_obj = cast_obj;
2978       }
2979     }
2980   }
2981 
2982   // Load the object's klass
2983   Node* obj_klass = load_object_klass(not_null_obj);
2984 
2985   // Generate the subtype check
2986   Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass);
2987 
2988   // Plug in the success path to the general merge in slot 1.
2989   region->init_req(_obj_path, control());
2990   phi   ->init_req(_obj_path, intcon(1));
2991 
2992   // Plug in the failing path to the general merge in slot 2.
2993   region->init_req(_fail_path, not_subtype_ctrl);
2994   phi   ->init_req(_fail_path, intcon(0));
2995 
2996   // Return final merged results
2997   set_control( _gvn.transform(region) );
2998   record_for_igvn(region);
2999 
3000   // If we know the type check always succeeds then we don't use the
3001   // profiling data at this bytecode. Don't lose it, feed it to the
3002   // type system as a speculative type.
3003   if (safe_for_replace) {
3004     Node* casted_obj = record_profiled_receiver_for_speculation(obj);
3005     replace_in_map(obj, casted_obj);
3006   }
3007 
3008   return _gvn.transform(phi);
3009 }
3010 
3011 //-------------------------------gen_checkcast---------------------------------
3012 // Generate a checkcast idiom.  Used by both the checkcast bytecode and the
3013 // array store bytecode.  Stack must be as-if BEFORE doing the bytecode so the
3014 // uncommon-trap paths work.  Adjust stack after this call.
3015 // If failure_control is supplied and not null, it is filled in with
3016 // the control edge for the cast failure.  Otherwise, an appropriate
3017 // uncommon trap or exception is thrown.
3018 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
3019                               Node* *failure_control) {
3020   kill_dead_locals();           // Benefit all the uncommon traps
3021   const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr();
3022   const Type *toop = TypeOopPtr::make_from_klass(tk->klass());
3023 
3024   // Fast cutout:  Check the case that the cast is vacuously true.
3025   // This detects the common cases where the test will short-circuit
3026   // away completely.  We do this before we perform the null check,
3027   // because if the test is going to turn into zero code, we don't
3028   // want a residual null check left around.  (Causes a slowdown,
3029   // for example, in some objArray manipulations, such as a[i]=a[j].)
3030   if (tk->singleton()) {
3031     const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
3032     if (objtp != NULL && objtp->klass() != NULL) {
3033       switch (C->static_subtype_check(tk->klass(), objtp->klass())) {
3034       case Compile::SSC_always_true:
3035         // If we know the type check always succeed then we don't use
3036         // the profiling data at this bytecode. Don't lose it, feed it
3037         // to the type system as a speculative type.
3038         return record_profiled_receiver_for_speculation(obj);
3039       case Compile::SSC_always_false:
3040         // It needs a null check because a null will *pass* the cast check.
3041         // A non-null value will always produce an exception.
3042         return null_assert(obj);
3043       }
3044     }
3045   }
3046 
3047   ciProfileData* data = NULL;
3048   bool safe_for_replace = false;
3049   if (failure_control == NULL) {        // use MDO in regular case only
3050     assert(java_bc() == Bytecodes::_aastore ||
3051            java_bc() == Bytecodes::_checkcast,
3052            "interpreter profiles type checks only for these BCs");
3053     data = method()->method_data()->bci_to_data(bci());
3054     safe_for_replace = true;
3055   }
3056 
3057   // Make the merge point
3058   enum { _obj_path = 1, _null_path, PATH_LIMIT };
3059   RegionNode* region = new RegionNode(PATH_LIMIT);
3060   Node*       phi    = new PhiNode(region, toop);
3061   C->set_has_split_ifs(true); // Has chance for split-if optimization
3062 
3063   // Use null-cast information if it is available
3064   bool speculative_not_null = false;
3065   bool never_see_null = ((failure_control == NULL)  // regular case only
3066                          && seems_never_null(obj, data, speculative_not_null));
3067 
3068   // Null check; get casted pointer; set region slot 3
3069   Node* null_ctl = top();
3070   Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3071 
3072   // If not_null_obj is dead, only null-path is taken
3073   if (stopped()) {              // Doing instance-of on a NULL?
3074     set_control(null_ctl);
3075     return null();
3076   }
3077   region->init_req(_null_path, null_ctl);
3078   phi   ->init_req(_null_path, null());  // Set null path value
3079   if (null_ctl == top()) {
3080     // Do this eagerly, so that pattern matches like is_diamond_phi
3081     // will work even during parsing.
3082     assert(_null_path == PATH_LIMIT-1, "delete last");
3083     region->del_req(_null_path);
3084     phi   ->del_req(_null_path);
3085   }
3086 
3087   Node* cast_obj = NULL;
3088   if (tk->klass_is_exact()) {
3089     // The following optimization tries to statically cast the speculative type of the object
3090     // (for example obtained during profiling) to the type of the superklass and then do a
3091     // dynamic check that the type of the object is what we expect. To work correctly
3092     // for checkcast and aastore the type of superklass should be exact.
3093     const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3094     // We may not have profiling here or it may not help us. If we have
3095     // a speculative type use it to perform an exact cast.
3096     ciKlass* spec_obj_type = obj_type->speculative_type();
3097     if (spec_obj_type != NULL || data != NULL) {
3098       cast_obj = maybe_cast_profiled_receiver(not_null_obj, tk->klass(), spec_obj_type, safe_for_replace);
3099       if (cast_obj != NULL) {
3100         if (failure_control != NULL) // failure is now impossible
3101           (*failure_control) = top();
3102         // adjust the type of the phi to the exact klass:
3103         phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3104       }
3105     }
3106   }
3107 
3108   if (cast_obj == NULL) {
3109     // Load the object's klass
3110     Node* obj_klass = load_object_klass(not_null_obj);
3111 
3112     // Generate the subtype check
3113     Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass );
3114 
3115     // Plug in success path into the merge
3116     cast_obj = _gvn.transform(new CheckCastPPNode(control(), not_null_obj, toop));
3117     // Failure path ends in uncommon trap (or may be dead - failure impossible)
3118     if (failure_control == NULL) {
3119       if (not_subtype_ctrl != top()) { // If failure is possible
3120         PreserveJVMState pjvms(this);
3121         set_control(not_subtype_ctrl);
3122         builtin_throw(Deoptimization::Reason_class_check, obj_klass);
3123       }
3124     } else {
3125       (*failure_control) = not_subtype_ctrl;
3126     }
3127   }
3128 
3129   region->init_req(_obj_path, control());
3130   phi   ->init_req(_obj_path, cast_obj);
3131 
3132   // A merge of NULL or Casted-NotNull obj
3133   Node* res = _gvn.transform(phi);
3134 
3135   // Note I do NOT always 'replace_in_map(obj,result)' here.
3136   //  if( tk->klass()->can_be_primary_super()  )
3137     // This means that if I successfully store an Object into an array-of-String
3138     // I 'forget' that the Object is really now known to be a String.  I have to
3139     // do this because we don't have true union types for interfaces - if I store
3140     // a Baz into an array-of-Interface and then tell the optimizer it's an
3141     // Interface, I forget that it's also a Baz and cannot do Baz-like field
3142     // references to it.  FIX THIS WHEN UNION TYPES APPEAR!
3143   //  replace_in_map( obj, res );
3144 
3145   // Return final merged results
3146   set_control( _gvn.transform(region) );
3147   record_for_igvn(region);
3148 
3149   return record_profiled_receiver_for_speculation(res);
3150 }
3151 
3152 //------------------------------next_monitor-----------------------------------
3153 // What number should be given to the next monitor?
3154 int GraphKit::next_monitor() {
3155   int current = jvms()->monitor_depth()* C->sync_stack_slots();
3156   int next = current + C->sync_stack_slots();
3157   // Keep the toplevel high water mark current:
3158   if (C->fixed_slots() < next)  C->set_fixed_slots(next);
3159   return current;
3160 }
3161 
3162 //------------------------------insert_mem_bar---------------------------------
3163 // Memory barrier to avoid floating things around
3164 // The membar serves as a pinch point between both control and all memory slices.
3165 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3166   MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3167   mb->init_req(TypeFunc::Control, control());
3168   mb->init_req(TypeFunc::Memory,  reset_memory());
3169   Node* membar = _gvn.transform(mb);
3170   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3171   set_all_memory_call(membar);
3172   return membar;
3173 }
3174 
3175 //-------------------------insert_mem_bar_volatile----------------------------
3176 // Memory barrier to avoid floating things around
3177 // The membar serves as a pinch point between both control and memory(alias_idx).
3178 // If you want to make a pinch point on all memory slices, do not use this
3179 // function (even with AliasIdxBot); use insert_mem_bar() instead.
3180 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3181   // When Parse::do_put_xxx updates a volatile field, it appends a series
3182   // of MemBarVolatile nodes, one for *each* volatile field alias category.
3183   // The first membar is on the same memory slice as the field store opcode.
3184   // This forces the membar to follow the store.  (Bug 6500685 broke this.)
3185   // All the other membars (for other volatile slices, including AliasIdxBot,
3186   // which stands for all unknown volatile slices) are control-dependent
3187   // on the first membar.  This prevents later volatile loads or stores
3188   // from sliding up past the just-emitted store.
3189 
3190   MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3191   mb->set_req(TypeFunc::Control,control());
3192   if (alias_idx == Compile::AliasIdxBot) {
3193     mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3194   } else {
3195     assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3196     mb->set_req(TypeFunc::Memory, memory(alias_idx));
3197   }
3198   Node* membar = _gvn.transform(mb);
3199   set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3200   if (alias_idx == Compile::AliasIdxBot) {
3201     merged_memory()->set_base_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)));
3202   } else {
3203     set_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)),alias_idx);
3204   }
3205   return membar;
3206 }
3207 
3208 //------------------------------shared_lock------------------------------------
3209 // Emit locking code.
3210 FastLockNode* GraphKit::shared_lock(Node* obj) {
3211   // bci is either a monitorenter bc or InvocationEntryBci
3212   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3213   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3214 
3215   if( !GenerateSynchronizationCode )
3216     return NULL;                // Not locking things?
3217   if (stopped())                // Dead monitor?
3218     return NULL;
3219 
3220   assert(dead_locals_are_killed(), "should kill locals before sync. point");
3221 
3222   // Box the stack location
3223   Node* box = _gvn.transform(new BoxLockNode(next_monitor()));
3224   Node* mem = reset_memory();
3225 
3226   FastLockNode * flock = _gvn.transform(new FastLockNode(0, obj, box) )->as_FastLock();
3227   if (UseBiasedLocking && PrintPreciseBiasedLockingStatistics) {
3228     // Create the counters for this fast lock.
3229     flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3230   }
3231 
3232   // Create the rtm counters for this fast lock if needed.
3233   flock->create_rtm_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3234 
3235   // Add monitor to debug info for the slow path.  If we block inside the
3236   // slow path and de-opt, we need the monitor hanging around
3237   map()->push_monitor( flock );
3238 
3239   const TypeFunc *tf = LockNode::lock_type();
3240   LockNode *lock = new LockNode(C, tf);
3241 
3242   lock->init_req( TypeFunc::Control, control() );
3243   lock->init_req( TypeFunc::Memory , mem );
3244   lock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
3245   lock->init_req( TypeFunc::FramePtr, frameptr() );
3246   lock->init_req( TypeFunc::ReturnAdr, top() );
3247 
3248   lock->init_req(TypeFunc::Parms + 0, obj);
3249   lock->init_req(TypeFunc::Parms + 1, box);
3250   lock->init_req(TypeFunc::Parms + 2, flock);
3251   add_safepoint_edges(lock);
3252 
3253   lock = _gvn.transform( lock )->as_Lock();
3254 
3255   // lock has no side-effects, sets few values
3256   set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3257 
3258   insert_mem_bar(Op_MemBarAcquireLock);
3259 
3260   // Add this to the worklist so that the lock can be eliminated
3261   record_for_igvn(lock);
3262 
3263 #ifndef PRODUCT
3264   if (PrintLockStatistics) {
3265     // Update the counter for this lock.  Don't bother using an atomic
3266     // operation since we don't require absolute accuracy.
3267     lock->create_lock_counter(map()->jvms());
3268     increment_counter(lock->counter()->addr());
3269   }
3270 #endif
3271 
3272   return flock;
3273 }
3274 
3275 
3276 //------------------------------shared_unlock----------------------------------
3277 // Emit unlocking code.
3278 void GraphKit::shared_unlock(Node* box, Node* obj) {
3279   // bci is either a monitorenter bc or InvocationEntryBci
3280   // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3281   assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3282 
3283   if( !GenerateSynchronizationCode )
3284     return;
3285   if (stopped()) {               // Dead monitor?
3286     map()->pop_monitor();        // Kill monitor from debug info
3287     return;
3288   }
3289 
3290   // Memory barrier to avoid floating things down past the locked region
3291   insert_mem_bar(Op_MemBarReleaseLock);
3292 
3293   const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3294   UnlockNode *unlock = new UnlockNode(C, tf);
3295 #ifdef ASSERT
3296   unlock->set_dbg_jvms(sync_jvms());
3297 #endif
3298   uint raw_idx = Compile::AliasIdxRaw;
3299   unlock->init_req( TypeFunc::Control, control() );
3300   unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3301   unlock->init_req( TypeFunc::I_O    , top() )     ;   // does no i/o
3302   unlock->init_req( TypeFunc::FramePtr, frameptr() );
3303   unlock->init_req( TypeFunc::ReturnAdr, top() );
3304 
3305   unlock->init_req(TypeFunc::Parms + 0, obj);
3306   unlock->init_req(TypeFunc::Parms + 1, box);
3307   unlock = _gvn.transform(unlock)->as_Unlock();
3308 
3309   Node* mem = reset_memory();
3310 
3311   // unlock has no side-effects, sets few values
3312   set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3313 
3314   // Kill monitor from debug info
3315   map()->pop_monitor( );
3316 }
3317 
3318 //-------------------------------get_layout_helper-----------------------------
3319 // If the given klass is a constant or known to be an array,
3320 // fetch the constant layout helper value into constant_value
3321 // and return (Node*)NULL.  Otherwise, load the non-constant
3322 // layout helper value, and return the node which represents it.
3323 // This two-faced routine is useful because allocation sites
3324 // almost always feature constant types.
3325 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3326   const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr();
3327   if (!StressReflectiveCode && inst_klass != NULL) {
3328     ciKlass* klass = inst_klass->klass();
3329     bool    xklass = inst_klass->klass_is_exact();
3330     if (xklass || klass->is_array_klass()) {
3331       jint lhelper = klass->layout_helper();
3332       if (lhelper != Klass::_lh_neutral_value) {
3333         constant_value = lhelper;
3334         return (Node*) NULL;
3335       }
3336     }
3337   }
3338   constant_value = Klass::_lh_neutral_value;  // put in a known value
3339   Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
3340   return make_load(NULL, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3341 }
3342 
3343 // We just put in an allocate/initialize with a big raw-memory effect.
3344 // Hook selected additional alias categories on the initialization.
3345 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3346                                 MergeMemNode* init_in_merge,
3347                                 Node* init_out_raw) {
3348   DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3349   assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3350 
3351   Node* prevmem = kit.memory(alias_idx);
3352   init_in_merge->set_memory_at(alias_idx, prevmem);
3353   kit.set_memory(init_out_raw, alias_idx);
3354 }
3355 
3356 //---------------------------set_output_for_allocation-------------------------
3357 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3358                                           const TypeOopPtr* oop_type,
3359                                           bool deoptimize_on_exception) {
3360   int rawidx = Compile::AliasIdxRaw;
3361   alloc->set_req( TypeFunc::FramePtr, frameptr() );
3362   add_safepoint_edges(alloc);
3363   Node* allocx = _gvn.transform(alloc);
3364   set_control( _gvn.transform(new ProjNode(allocx, TypeFunc::Control) ) );
3365   // create memory projection for i_o
3366   set_memory ( _gvn.transform( new ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3367   make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception);
3368 
3369   // create a memory projection as for the normal control path
3370   Node* malloc = _gvn.transform(new ProjNode(allocx, TypeFunc::Memory));
3371   set_memory(malloc, rawidx);
3372 
3373   // a normal slow-call doesn't change i_o, but an allocation does
3374   // we create a separate i_o projection for the normal control path
3375   set_i_o(_gvn.transform( new ProjNode(allocx, TypeFunc::I_O, false) ) );
3376   Node* rawoop = _gvn.transform( new ProjNode(allocx, TypeFunc::Parms) );
3377 
3378   // put in an initialization barrier
3379   InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3380                                                  rawoop)->as_Initialize();
3381   assert(alloc->initialization() == init,  "2-way macro link must work");
3382   assert(init ->allocation()     == alloc, "2-way macro link must work");
3383   {
3384     // Extract memory strands which may participate in the new object's
3385     // initialization, and source them from the new InitializeNode.
3386     // This will allow us to observe initializations when they occur,
3387     // and link them properly (as a group) to the InitializeNode.
3388     assert(init->in(InitializeNode::Memory) == malloc, "");
3389     MergeMemNode* minit_in = MergeMemNode::make(malloc);
3390     init->set_req(InitializeNode::Memory, minit_in);
3391     record_for_igvn(minit_in); // fold it up later, if possible
3392     Node* minit_out = memory(rawidx);
3393     assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3394     if (oop_type->isa_aryptr()) {
3395       const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3396       int            elemidx  = C->get_alias_index(telemref);
3397       hook_memory_on_init(*this, elemidx, minit_in, minit_out);
3398     } else if (oop_type->isa_instptr()) {
3399       ciInstanceKlass* ik = oop_type->klass()->as_instance_klass();
3400       for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3401         ciField* field = ik->nonstatic_field_at(i);
3402         if (field->offset() >= TrackedInitializationLimit * HeapWordSize)
3403           continue;  // do not bother to track really large numbers of fields
3404         // Find (or create) the alias category for this field:
3405         int fieldidx = C->alias_type(field)->index();
3406         hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3407       }
3408     }
3409   }
3410 
3411   // Cast raw oop to the real thing...
3412   Node* javaoop = new CheckCastPPNode(control(), rawoop, oop_type);
3413   javaoop = _gvn.transform(javaoop);
3414   C->set_recent_alloc(control(), javaoop);
3415   assert(just_allocated_object(control()) == javaoop, "just allocated");
3416 
3417 #ifdef ASSERT
3418   { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3419     assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc,
3420            "Ideal_allocation works");
3421     assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc,
3422            "Ideal_allocation works");
3423     if (alloc->is_AllocateArray()) {
3424       assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(),
3425              "Ideal_allocation works");
3426       assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(),
3427              "Ideal_allocation works");
3428     } else {
3429       assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3430     }
3431   }
3432 #endif //ASSERT
3433 
3434   return javaoop;
3435 }
3436 
3437 //---------------------------new_instance--------------------------------------
3438 // This routine takes a klass_node which may be constant (for a static type)
3439 // or may be non-constant (for reflective code).  It will work equally well
3440 // for either, and the graph will fold nicely if the optimizer later reduces
3441 // the type to a constant.
3442 // The optional arguments are for specialized use by intrinsics:
3443 //  - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3444 //  - If 'return_size_val', report the the total object size to the caller.
3445 //  - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3446 Node* GraphKit::new_instance(Node* klass_node,
3447                              Node* extra_slow_test,
3448                              Node* *return_size_val,
3449                              bool deoptimize_on_exception) {
3450   // Compute size in doublewords
3451   // The size is always an integral number of doublewords, represented
3452   // as a positive bytewise size stored in the klass's layout_helper.
3453   // The layout_helper also encodes (in a low bit) the need for a slow path.
3454   jint  layout_con = Klass::_lh_neutral_value;
3455   Node* layout_val = get_layout_helper(klass_node, layout_con);
3456   int   layout_is_con = (layout_val == NULL);
3457 
3458   if (extra_slow_test == NULL)  extra_slow_test = intcon(0);
3459   // Generate the initial go-slow test.  It's either ALWAYS (return a
3460   // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective
3461   // case) a computed value derived from the layout_helper.
3462   Node* initial_slow_test = NULL;
3463   if (layout_is_con) {
3464     assert(!StressReflectiveCode, "stress mode does not use these paths");
3465     bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3466     initial_slow_test = must_go_slow ? intcon(1) : extra_slow_test;
3467   } else {   // reflective case
3468     // This reflective path is used by Unsafe.allocateInstance.
3469     // (It may be stress-tested by specifying StressReflectiveCode.)
3470     // Basically, we want to get into the VM is there's an illegal argument.
3471     Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3472     initial_slow_test = _gvn.transform( new AndINode(layout_val, bit) );
3473     if (extra_slow_test != intcon(0)) {
3474       initial_slow_test = _gvn.transform( new OrINode(initial_slow_test, extra_slow_test) );
3475     }
3476     // (Macro-expander will further convert this to a Bool, if necessary.)
3477   }
3478 
3479   // Find the size in bytes.  This is easy; it's the layout_helper.
3480   // The size value must be valid even if the slow path is taken.
3481   Node* size = NULL;
3482   if (layout_is_con) {
3483     size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3484   } else {   // reflective case
3485     // This reflective path is used by clone and Unsafe.allocateInstance.
3486     size = ConvI2X(layout_val);
3487 
3488     // Clear the low bits to extract layout_helper_size_in_bytes:
3489     assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3490     Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3491     size = _gvn.transform( new AndXNode(size, mask) );
3492   }
3493   if (return_size_val != NULL) {
3494     (*return_size_val) = size;
3495   }
3496 
3497   // This is a precise notnull oop of the klass.
3498   // (Actually, it need not be precise if this is a reflective allocation.)
3499   // It's what we cast the result to.
3500   const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3501   if (!tklass)  tklass = TypeKlassPtr::OBJECT;
3502   const TypeOopPtr* oop_type = tklass->as_instance_type();
3503 
3504   // Now generate allocation code
3505 
3506   // The entire memory state is needed for slow path of the allocation
3507   // since GC and deoptimization can happened.
3508   Node *mem = reset_memory();
3509   set_all_memory(mem); // Create new memory state
3510 
3511   AllocateNode* alloc = new AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3512                                          control(), mem, i_o(),
3513                                          size, klass_node,
3514                                          initial_slow_test);
3515 
3516   return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception);
3517 }
3518 
3519 //-------------------------------new_array-------------------------------------
3520 // helper for both newarray and anewarray
3521 // The 'length' parameter is (obviously) the length of the array.
3522 // See comments on new_instance for the meaning of the other arguments.
3523 Node* GraphKit::new_array(Node* klass_node,     // array klass (maybe variable)
3524                           Node* length,         // number of array elements
3525                           int   nargs,          // number of arguments to push back for uncommon trap
3526                           Node* *return_size_val,
3527                           bool deoptimize_on_exception) {
3528   jint  layout_con = Klass::_lh_neutral_value;
3529   Node* layout_val = get_layout_helper(klass_node, layout_con);
3530   int   layout_is_con = (layout_val == NULL);
3531 
3532   if (!layout_is_con && !StressReflectiveCode &&
3533       !too_many_traps(Deoptimization::Reason_class_check)) {
3534     // This is a reflective array creation site.
3535     // Optimistically assume that it is a subtype of Object[],
3536     // so that we can fold up all the address arithmetic.
3537     layout_con = Klass::array_layout_helper(T_OBJECT);
3538     Node* cmp_lh = _gvn.transform( new CmpINode(layout_val, intcon(layout_con)) );
3539     Node* bol_lh = _gvn.transform( new BoolNode(cmp_lh, BoolTest::eq) );
3540     { BuildCutout unless(this, bol_lh, PROB_MAX);
3541       inc_sp(nargs);
3542       uncommon_trap(Deoptimization::Reason_class_check,
3543                     Deoptimization::Action_maybe_recompile);
3544     }
3545     layout_val = NULL;
3546     layout_is_con = true;
3547   }
3548 
3549   // Generate the initial go-slow test.  Make sure we do not overflow
3550   // if length is huge (near 2Gig) or negative!  We do not need
3551   // exact double-words here, just a close approximation of needed
3552   // double-words.  We can't add any offset or rounding bits, lest we
3553   // take a size -1 of bytes and make it positive.  Use an unsigned
3554   // compare, so negative sizes look hugely positive.
3555   int fast_size_limit = FastAllocateSizeLimit;
3556   if (layout_is_con) {
3557     assert(!StressReflectiveCode, "stress mode does not use these paths");
3558     // Increase the size limit if we have exact knowledge of array type.
3559     int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3560     fast_size_limit <<= (LogBytesPerLong - log2_esize);
3561   }
3562 
3563   Node* initial_slow_cmp  = _gvn.transform( new CmpUNode( length, intcon( fast_size_limit ) ) );
3564   Node* initial_slow_test = _gvn.transform( new BoolNode( initial_slow_cmp, BoolTest::gt ) );
3565 
3566   // --- Size Computation ---
3567   // array_size = round_to_heap(array_header + (length << elem_shift));
3568   // where round_to_heap(x) == align_to(x, MinObjAlignmentInBytes)
3569   // and align_to(x, y) == ((x + y-1) & ~(y-1))
3570   // The rounding mask is strength-reduced, if possible.
3571   int round_mask = MinObjAlignmentInBytes - 1;
3572   Node* header_size = NULL;
3573   int   header_size_min  = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3574   // (T_BYTE has the weakest alignment and size restrictions...)
3575   if (layout_is_con) {
3576     int       hsize  = Klass::layout_helper_header_size(layout_con);
3577     int       eshift = Klass::layout_helper_log2_element_size(layout_con);
3578     BasicType etype  = Klass::layout_helper_element_type(layout_con);
3579     if ((round_mask & ~right_n_bits(eshift)) == 0)
3580       round_mask = 0;  // strength-reduce it if it goes away completely
3581     assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3582     assert(header_size_min <= hsize, "generic minimum is smallest");
3583     header_size_min = hsize;
3584     header_size = intcon(hsize + round_mask);
3585   } else {
3586     Node* hss   = intcon(Klass::_lh_header_size_shift);
3587     Node* hsm   = intcon(Klass::_lh_header_size_mask);
3588     Node* hsize = _gvn.transform( new URShiftINode(layout_val, hss) );
3589     hsize       = _gvn.transform( new AndINode(hsize, hsm) );
3590     Node* mask  = intcon(round_mask);
3591     header_size = _gvn.transform( new AddINode(hsize, mask) );
3592   }
3593 
3594   Node* elem_shift = NULL;
3595   if (layout_is_con) {
3596     int eshift = Klass::layout_helper_log2_element_size(layout_con);
3597     if (eshift != 0)
3598       elem_shift = intcon(eshift);
3599   } else {
3600     // There is no need to mask or shift this value.
3601     // The semantics of LShiftINode include an implicit mask to 0x1F.
3602     assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3603     elem_shift = layout_val;
3604   }
3605 
3606   // Transition to native address size for all offset calculations:
3607   Node* lengthx = ConvI2X(length);
3608   Node* headerx = ConvI2X(header_size);
3609 #ifdef _LP64
3610   { const TypeInt* tilen = _gvn.find_int_type(length);
3611     if (tilen != NULL && tilen->_lo < 0) {
3612       // Add a manual constraint to a positive range.  Cf. array_element_address.
3613       jint size_max = fast_size_limit;
3614       if (size_max > tilen->_hi)  size_max = tilen->_hi;
3615       const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin);
3616 
3617       // Only do a narrow I2L conversion if the range check passed.
3618       IfNode* iff = new IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
3619       _gvn.transform(iff);
3620       RegionNode* region = new RegionNode(3);
3621       _gvn.set_type(region, Type::CONTROL);
3622       lengthx = new PhiNode(region, TypeLong::LONG);
3623       _gvn.set_type(lengthx, TypeLong::LONG);
3624 
3625       // Range check passed. Use ConvI2L node with narrow type.
3626       Node* passed = IfFalse(iff);
3627       region->init_req(1, passed);
3628       // Make I2L conversion control dependent to prevent it from
3629       // floating above the range check during loop optimizations.
3630       lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed));
3631 
3632       // Range check failed. Use ConvI2L with wide type because length may be invalid.
3633       region->init_req(2, IfTrue(iff));
3634       lengthx->init_req(2, ConvI2X(length));
3635 
3636       set_control(region);
3637       record_for_igvn(region);
3638       record_for_igvn(lengthx);
3639     }
3640   }
3641 #endif
3642 
3643   // Combine header size (plus rounding) and body size.  Then round down.
3644   // This computation cannot overflow, because it is used only in two
3645   // places, one where the length is sharply limited, and the other
3646   // after a successful allocation.
3647   Node* abody = lengthx;
3648   if (elem_shift != NULL)
3649     abody     = _gvn.transform( new LShiftXNode(lengthx, elem_shift) );
3650   Node* size  = _gvn.transform( new AddXNode(headerx, abody) );
3651   if (round_mask != 0) {
3652     Node* mask = MakeConX(~round_mask);
3653     size       = _gvn.transform( new AndXNode(size, mask) );
3654   }
3655   // else if round_mask == 0, the size computation is self-rounding
3656 
3657   if (return_size_val != NULL) {
3658     // This is the size
3659     (*return_size_val) = size;
3660   }
3661 
3662   // Now generate allocation code
3663 
3664   // The entire memory state is needed for slow path of the allocation
3665   // since GC and deoptimization can happened.
3666   Node *mem = reset_memory();
3667   set_all_memory(mem); // Create new memory state
3668 
3669   if (initial_slow_test->is_Bool()) {
3670     // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3671     initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3672   }
3673 
3674   // Create the AllocateArrayNode and its result projections
3675   AllocateArrayNode* alloc
3676     = new AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
3677                             control(), mem, i_o(),
3678                             size, klass_node,
3679                             initial_slow_test,
3680                             length);
3681 
3682   // Cast to correct type.  Note that the klass_node may be constant or not,
3683   // and in the latter case the actual array type will be inexact also.
3684   // (This happens via a non-constant argument to inline_native_newArray.)
3685   // In any case, the value of klass_node provides the desired array type.
3686   const TypeInt* length_type = _gvn.find_int_type(length);
3687   const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3688   if (ary_type->isa_aryptr() && length_type != NULL) {
3689     // Try to get a better type than POS for the size
3690     ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3691   }
3692 
3693   Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception);
3694 
3695   // Cast length on remaining path to be as narrow as possible
3696   if (map()->find_edge(length) >= 0) {
3697     Node* ccast = alloc->make_ideal_length(ary_type, &_gvn);
3698     if (ccast != length) {
3699       _gvn.set_type_bottom(ccast);
3700       record_for_igvn(ccast);
3701       replace_in_map(length, ccast);
3702     }
3703   }
3704 
3705   return javaoop;
3706 }
3707 
3708 // The following "Ideal_foo" functions are placed here because they recognize
3709 // the graph shapes created by the functions immediately above.
3710 
3711 //---------------------------Ideal_allocation----------------------------------
3712 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3713 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) {
3714   if (ptr == NULL) {     // reduce dumb test in callers
3715     return NULL;
3716   }
3717   if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
3718     ptr = ptr->in(1);
3719     if (ptr == NULL) return NULL;
3720   }
3721   // Return NULL for allocations with several casts:
3722   //   j.l.reflect.Array.newInstance(jobject, jint)
3723   //   Object.clone()
3724   // to keep more precise type from last cast.
3725   if (ptr->is_Proj()) {
3726     Node* allo = ptr->in(0);
3727     if (allo != NULL && allo->is_Allocate()) {
3728       return allo->as_Allocate();
3729     }
3730   }
3731   // Report failure to match.
3732   return NULL;
3733 }
3734 
3735 // Fancy version which also strips off an offset (and reports it to caller).
3736 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase,
3737                                              intptr_t& offset) {
3738   Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
3739   if (base == NULL)  return NULL;
3740   return Ideal_allocation(base, phase);
3741 }
3742 
3743 // Trace Initialize <- Proj[Parm] <- Allocate
3744 AllocateNode* InitializeNode::allocation() {
3745   Node* rawoop = in(InitializeNode::RawAddress);
3746   if (rawoop->is_Proj()) {
3747     Node* alloc = rawoop->in(0);
3748     if (alloc->is_Allocate()) {
3749       return alloc->as_Allocate();
3750     }
3751   }
3752   return NULL;
3753 }
3754 
3755 // Trace Allocate -> Proj[Parm] -> Initialize
3756 InitializeNode* AllocateNode::initialization() {
3757   ProjNode* rawoop = proj_out_or_null(AllocateNode::RawAddress);
3758   if (rawoop == NULL)  return NULL;
3759   for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3760     Node* init = rawoop->fast_out(i);
3761     if (init->is_Initialize()) {
3762       assert(init->as_Initialize()->allocation() == this, "2-way link");
3763       return init->as_Initialize();
3764     }
3765   }
3766   return NULL;
3767 }
3768 
3769 //----------------------------- loop predicates ---------------------------
3770 
3771 //------------------------------add_predicate_impl----------------------------
3772 void GraphKit::add_predicate_impl(Deoptimization::DeoptReason reason, int nargs) {
3773   // Too many traps seen?
3774   if (too_many_traps(reason)) {
3775 #ifdef ASSERT
3776     if (TraceLoopPredicate) {
3777       int tc = C->trap_count(reason);
3778       tty->print("too many traps=%s tcount=%d in ",
3779                     Deoptimization::trap_reason_name(reason), tc);
3780       method()->print(); // which method has too many predicate traps
3781       tty->cr();
3782     }
3783 #endif
3784     // We cannot afford to take more traps here,
3785     // do not generate predicate.
3786     return;
3787   }
3788 
3789   Node *cont    = _gvn.intcon(1);
3790   Node* opq     = _gvn.transform(new Opaque1Node(C, cont));
3791   Node *bol     = _gvn.transform(new Conv2BNode(opq));
3792   IfNode* iff   = create_and_map_if(control(), bol, PROB_MAX, COUNT_UNKNOWN);
3793   Node* iffalse = _gvn.transform(new IfFalseNode(iff));
3794   C->add_predicate_opaq(opq);
3795   {
3796     PreserveJVMState pjvms(this);
3797     set_control(iffalse);
3798     inc_sp(nargs);
3799     uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
3800   }
3801   Node* iftrue = _gvn.transform(new IfTrueNode(iff));
3802   set_control(iftrue);
3803 }
3804 
3805 //------------------------------add_predicate---------------------------------
3806 void GraphKit::add_predicate(int nargs) {
3807   if (UseLoopPredicate) {
3808     add_predicate_impl(Deoptimization::Reason_predicate, nargs);
3809   }
3810   // loop's limit check predicate should be near the loop.
3811   add_predicate_impl(Deoptimization::Reason_loop_limit_check, nargs);
3812 }
3813 
3814 //----------------------------- store barriers ----------------------------
3815 #define __ ideal.
3816 
3817 void GraphKit::sync_kit(IdealKit& ideal) {
3818   set_all_memory(__ merged_memory());
3819   set_i_o(__ i_o());
3820   set_control(__ ctrl());
3821 }
3822 
3823 void GraphKit::final_sync(IdealKit& ideal) {
3824   // Final sync IdealKit and graphKit.
3825   sync_kit(ideal);
3826 }
3827 
3828 Node* GraphKit::byte_map_base_node() {
3829   // Get base of card map
3830   CardTableModRefBS* ct =
3831     barrier_set_cast<CardTableModRefBS>(Universe::heap()->barrier_set());
3832   assert(sizeof(*ct->byte_map_base) == sizeof(jbyte), "adjust users of this code");
3833   if (ct->byte_map_base != NULL) {
3834     return makecon(TypeRawPtr::make((address)ct->byte_map_base));
3835   } else {
3836     return null();
3837   }
3838 }
3839 
3840 // vanilla/CMS post barrier
3841 // Insert a write-barrier store.  This is to let generational GC work; we have
3842 // to flag all oop-stores before the next GC point.
3843 void GraphKit::write_barrier_post(Node* oop_store,
3844                                   Node* obj,
3845                                   Node* adr,
3846                                   uint  adr_idx,
3847                                   Node* val,
3848                                   bool use_precise) {
3849   // No store check needed if we're storing a NULL or an old object
3850   // (latter case is probably a string constant). The concurrent
3851   // mark sweep garbage collector, however, needs to have all nonNull
3852   // oop updates flagged via card-marks.
3853   if (val != NULL && val->is_Con()) {
3854     // must be either an oop or NULL
3855     const Type* t = val->bottom_type();
3856     if (t == TypePtr::NULL_PTR || t == Type::TOP)
3857       // stores of null never (?) need barriers
3858       return;
3859   }
3860 
3861   if (use_ReduceInitialCardMarks()
3862       && obj == just_allocated_object(control())) {
3863     // We can skip marks on a freshly-allocated object in Eden.
3864     // Keep this code in sync with new_store_pre_barrier() in runtime.cpp.
3865     // That routine informs GC to take appropriate compensating steps,
3866     // upon a slow-path allocation, so as to make this card-mark
3867     // elision safe.
3868     return;
3869   }
3870 
3871   if (!use_precise) {
3872     // All card marks for a (non-array) instance are in one place:
3873     adr = obj;
3874   }
3875   // (Else it's an array (or unknown), and we want more precise card marks.)
3876   assert(adr != NULL, "");
3877 
3878   IdealKit ideal(this, true);
3879 
3880   // Convert the pointer to an int prior to doing math on it
3881   Node* cast = __ CastPX(__ ctrl(), adr);
3882 
3883   // Divide by card size
3884   assert(Universe::heap()->barrier_set()->is_a(BarrierSet::CardTableModRef),
3885          "Only one we handle so far.");
3886   Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3887 
3888   // Combine card table base and card offset
3889   Node* card_adr = __ AddP(__ top(), byte_map_base_node(), card_offset );
3890 
3891   // Get the alias_index for raw card-mark memory
3892   int adr_type = Compile::AliasIdxRaw;
3893   Node*   zero = __ ConI(0); // Dirty card value
3894   BasicType bt = T_BYTE;
3895 
3896   if (UseConcMarkSweepGC && UseCondCardMark) {
3897     insert_mem_bar(Op_MemBarVolatile);   // StoreLoad barrier
3898     __ sync_kit(this);
3899   }
3900 
3901   if (UseCondCardMark) {
3902     // The classic GC reference write barrier is typically implemented
3903     // as a store into the global card mark table.  Unfortunately
3904     // unconditional stores can result in false sharing and excessive
3905     // coherence traffic as well as false transactional aborts.
3906     // UseCondCardMark enables MP "polite" conditional card mark
3907     // stores.  In theory we could relax the load from ctrl() to
3908     // no_ctrl, but that doesn't buy much latitude.
3909     Node* card_val = __ load( __ ctrl(), card_adr, TypeInt::BYTE, bt, adr_type);
3910     __ if_then(card_val, BoolTest::ne, zero);
3911   }
3912 
3913   // Smash zero into card
3914   if( !UseConcMarkSweepGC ) {
3915     __ store(__ ctrl(), card_adr, zero, bt, adr_type, MemNode::unordered);
3916   } else {
3917     // Specialized path for CM store barrier
3918     __ storeCM(__ ctrl(), card_adr, zero, oop_store, adr_idx, bt, adr_type);
3919   }
3920 
3921   if (UseCondCardMark) {
3922     __ end_if();
3923   }
3924 
3925   // Final sync IdealKit and GraphKit.
3926   final_sync(ideal);
3927 }
3928 /*
3929  * Determine if the G1 pre-barrier can be removed. The pre-barrier is
3930  * required by SATB to make sure all objects live at the start of the
3931  * marking are kept alive, all reference updates need to any previous
3932  * reference stored before writing.
3933  *
3934  * If the previous value is NULL there is no need to save the old value.
3935  * References that are NULL are filtered during runtime by the barrier
3936  * code to avoid unnecessary queuing.
3937  *
3938  * However in the case of newly allocated objects it might be possible to
3939  * prove that the reference about to be overwritten is NULL during compile
3940  * time and avoid adding the barrier code completely.
3941  *
3942  * The compiler needs to determine that the object in which a field is about
3943  * to be written is newly allocated, and that no prior store to the same field
3944  * has happened since the allocation.
3945  *
3946  * Returns true if the pre-barrier can be removed
3947  */
3948 bool GraphKit::g1_can_remove_pre_barrier(PhaseTransform* phase, Node* adr,
3949                                          BasicType bt, uint adr_idx) {
3950   intptr_t offset = 0;
3951   Node* base = AddPNode::Ideal_base_and_offset(adr, phase, offset);
3952   AllocateNode* alloc = AllocateNode::Ideal_allocation(base, phase);
3953 
3954   if (offset == Type::OffsetBot) {
3955     return false; // cannot unalias unless there are precise offsets
3956   }
3957 
3958   if (alloc == NULL) {
3959     return false; // No allocation found
3960   }
3961 
3962   intptr_t size_in_bytes = type2aelembytes(bt);
3963 
3964   Node* mem = memory(adr_idx); // start searching here...
3965 
3966   for (int cnt = 0; cnt < 50; cnt++) {
3967 
3968     if (mem->is_Store()) {
3969 
3970       Node* st_adr = mem->in(MemNode::Address);
3971       intptr_t st_offset = 0;
3972       Node* st_base = AddPNode::Ideal_base_and_offset(st_adr, phase, st_offset);
3973 
3974       if (st_base == NULL) {
3975         break; // inscrutable pointer
3976       }
3977 
3978       // Break we have found a store with same base and offset as ours so break
3979       if (st_base == base && st_offset == offset) {
3980         break;
3981       }
3982 
3983       if (st_offset != offset && st_offset != Type::OffsetBot) {
3984         const int MAX_STORE = BytesPerLong;
3985         if (st_offset >= offset + size_in_bytes ||
3986             st_offset <= offset - MAX_STORE ||
3987             st_offset <= offset - mem->as_Store()->memory_size()) {
3988           // Success:  The offsets are provably independent.
3989           // (You may ask, why not just test st_offset != offset and be done?
3990           // The answer is that stores of different sizes can co-exist
3991           // in the same sequence of RawMem effects.  We sometimes initialize
3992           // a whole 'tile' of array elements with a single jint or jlong.)
3993           mem = mem->in(MemNode::Memory);
3994           continue; // advance through independent store memory
3995         }
3996       }
3997 
3998       if (st_base != base
3999           && MemNode::detect_ptr_independence(base, alloc, st_base,
4000                                               AllocateNode::Ideal_allocation(st_base, phase),
4001                                               phase)) {
4002         // Success:  The bases are provably independent.
4003         mem = mem->in(MemNode::Memory);
4004         continue; // advance through independent store memory
4005       }
4006     } else if (mem->is_Proj() && mem->in(0)->is_Initialize()) {
4007 
4008       InitializeNode* st_init = mem->in(0)->as_Initialize();
4009       AllocateNode* st_alloc = st_init->allocation();
4010 
4011       // Make sure that we are looking at the same allocation site.
4012       // The alloc variable is guaranteed to not be null here from earlier check.
4013       if (alloc == st_alloc) {
4014         // Check that the initialization is storing NULL so that no previous store
4015         // has been moved up and directly write a reference
4016         Node* captured_store = st_init->find_captured_store(offset,
4017                                                             type2aelembytes(T_OBJECT),
4018                                                             phase);
4019         if (captured_store == NULL || captured_store == st_init->zero_memory()) {
4020           return true;
4021         }
4022       }
4023     }
4024 
4025     // Unless there is an explicit 'continue', we must bail out here,
4026     // because 'mem' is an inscrutable memory state (e.g., a call).
4027     break;
4028   }
4029 
4030   return false;
4031 }
4032 
4033 // G1 pre/post barriers
4034 void GraphKit::g1_write_barrier_pre(bool do_load,
4035                                     Node* obj,
4036                                     Node* adr,
4037                                     uint alias_idx,
4038                                     Node* val,
4039                                     const TypeOopPtr* val_type,
4040                                     Node* pre_val,
4041                                     BasicType bt) {
4042 
4043   // Some sanity checks
4044   // Note: val is unused in this routine.
4045 
4046   if (do_load) {
4047     // We need to generate the load of the previous value
4048     assert(obj != NULL, "must have a base");
4049     assert(adr != NULL, "where are loading from?");
4050     assert(pre_val == NULL, "loaded already?");
4051     assert(val_type != NULL, "need a type");
4052 
4053     if (use_ReduceInitialCardMarks()
4054         && g1_can_remove_pre_barrier(&_gvn, adr, bt, alias_idx)) {
4055       return;
4056     }
4057 
4058   } else {
4059     // In this case both val_type and alias_idx are unused.
4060     assert(pre_val != NULL, "must be loaded already");
4061     // Nothing to be done if pre_val is null.
4062     if (pre_val->bottom_type() == TypePtr::NULL_PTR) return;
4063     assert(pre_val->bottom_type()->basic_type() == T_OBJECT, "or we shouldn't be here");
4064   }
4065   assert(bt == T_OBJECT, "or we shouldn't be here");
4066 
4067   IdealKit ideal(this, true);
4068 
4069   Node* tls = __ thread(); // ThreadLocalStorage
4070 
4071   Node* no_ctrl = NULL;
4072   Node* no_base = __ top();
4073   Node* zero  = __ ConI(0);
4074   Node* zeroX = __ ConX(0);
4075 
4076   float likely  = PROB_LIKELY(0.999);
4077   float unlikely  = PROB_UNLIKELY(0.999);
4078 
4079   BasicType active_type = in_bytes(SATBMarkQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE;
4080   assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 4 || in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "flag width");
4081 
4082   // Offsets into the thread
4083   const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() +  // 648
4084                                           SATBMarkQueue::byte_offset_of_active());
4085   const int index_offset   = in_bytes(JavaThread::satb_mark_queue_offset() +  // 656
4086                                           SATBMarkQueue::byte_offset_of_index());
4087   const int buffer_offset  = in_bytes(JavaThread::satb_mark_queue_offset() +  // 652
4088                                           SATBMarkQueue::byte_offset_of_buf());
4089 
4090   // Now the actual pointers into the thread
4091   Node* marking_adr = __ AddP(no_base, tls, __ ConX(marking_offset));
4092   Node* buffer_adr  = __ AddP(no_base, tls, __ ConX(buffer_offset));
4093   Node* index_adr   = __ AddP(no_base, tls, __ ConX(index_offset));
4094 
4095   // Now some of the values
4096   Node* marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw);
4097 
4098   // if (!marking)
4099   __ if_then(marking, BoolTest::ne, zero, unlikely); {
4100     BasicType index_bt = TypeX_X->basic_type();
4101     assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading G1 SATBMarkQueue::_index with wrong size.");
4102     Node* index   = __ load(__ ctrl(), index_adr, TypeX_X, index_bt, Compile::AliasIdxRaw);
4103 
4104     if (do_load) {
4105       // load original value
4106       // alias_idx correct??
4107       pre_val = __ load(__ ctrl(), adr, val_type, bt, alias_idx);
4108     }
4109 
4110     // if (pre_val != NULL)
4111     __ if_then(pre_val, BoolTest::ne, null()); {
4112       Node* buffer  = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
4113 
4114       // is the queue for this thread full?
4115       __ if_then(index, BoolTest::ne, zeroX, likely); {
4116 
4117         // decrement the index
4118         Node* next_index = _gvn.transform(new SubXNode(index, __ ConX(sizeof(intptr_t))));
4119 
4120         // Now get the buffer location we will log the previous value into and store it
4121         Node *log_addr = __ AddP(no_base, buffer, next_index);
4122         __ store(__ ctrl(), log_addr, pre_val, T_OBJECT, Compile::AliasIdxRaw, MemNode::unordered);
4123         // update the index
4124         __ store(__ ctrl(), index_adr, next_index, index_bt, Compile::AliasIdxRaw, MemNode::unordered);
4125 
4126       } __ else_(); {
4127 
4128         // logging buffer is full, call the runtime
4129         const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type();
4130         __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", pre_val, tls);
4131       } __ end_if();  // (!index)
4132     } __ end_if();  // (pre_val != NULL)
4133   } __ end_if();  // (!marking)
4134 
4135   // Final sync IdealKit and GraphKit.
4136   final_sync(ideal);
4137 }
4138 
4139 /*
4140  * G1 similar to any GC with a Young Generation requires a way to keep track of
4141  * references from Old Generation to Young Generation to make sure all live
4142  * objects are found. G1 also requires to keep track of object references
4143  * between different regions to enable evacuation of old regions, which is done
4144  * as part of mixed collections. References are tracked in remembered sets and
4145  * is continuously updated as reference are written to with the help of the
4146  * post-barrier.
4147  *
4148  * To reduce the number of updates to the remembered set the post-barrier
4149  * filters updates to fields in objects located in the Young Generation,
4150  * the same region as the reference, when the NULL is being written or
4151  * if the card is already marked as dirty by an earlier write.
4152  *
4153  * Under certain circumstances it is possible to avoid generating the
4154  * post-barrier completely if it is possible during compile time to prove
4155  * the object is newly allocated and that no safepoint exists between the
4156  * allocation and the store.
4157  *
4158  * In the case of slow allocation the allocation code must handle the barrier
4159  * as part of the allocation in the case the allocated object is not located
4160  * in the nursery, this would happen for humongous objects. This is similar to
4161  * how CMS is required to handle this case, see the comments for the method
4162  * CollectedHeap::new_store_pre_barrier and OptoRuntime::new_store_pre_barrier.
4163  * A deferred card mark is required for these objects and handled in the above
4164  * mentioned methods.
4165  *
4166  * Returns true if the post barrier can be removed
4167  */
4168 bool GraphKit::g1_can_remove_post_barrier(PhaseTransform* phase, Node* store,
4169                                           Node* adr) {
4170   intptr_t      offset = 0;
4171   Node*         base   = AddPNode::Ideal_base_and_offset(adr, phase, offset);
4172   AllocateNode* alloc  = AllocateNode::Ideal_allocation(base, phase);
4173 
4174   if (offset == Type::OffsetBot) {
4175     return false; // cannot unalias unless there are precise offsets
4176   }
4177 
4178   if (alloc == NULL) {
4179      return false; // No allocation found
4180   }
4181 
4182   // Start search from Store node
4183   Node* mem = store->in(MemNode::Control);
4184   if (mem->is_Proj() && mem->in(0)->is_Initialize()) {
4185 
4186     InitializeNode* st_init = mem->in(0)->as_Initialize();
4187     AllocateNode*  st_alloc = st_init->allocation();
4188 
4189     // Make sure we are looking at the same allocation
4190     if (alloc == st_alloc) {
4191       return true;
4192     }
4193   }
4194 
4195   return false;
4196 }
4197 
4198 //
4199 // Update the card table and add card address to the queue
4200 //
4201 void GraphKit::g1_mark_card(IdealKit& ideal,
4202                             Node* card_adr,
4203                             Node* oop_store,
4204                             uint oop_alias_idx,
4205                             Node* index,
4206                             Node* index_adr,
4207                             Node* buffer,
4208                             const TypeFunc* tf) {
4209 
4210   Node* zero  = __ ConI(0);
4211   Node* zeroX = __ ConX(0);
4212   Node* no_base = __ top();
4213   BasicType card_bt = T_BYTE;
4214   // Smash zero into card. MUST BE ORDERED WRT TO STORE
4215   __ storeCM(__ ctrl(), card_adr, zero, oop_store, oop_alias_idx, card_bt, Compile::AliasIdxRaw);
4216 
4217   //  Now do the queue work
4218   __ if_then(index, BoolTest::ne, zeroX); {
4219 
4220     Node* next_index = _gvn.transform(new SubXNode(index, __ ConX(sizeof(intptr_t))));
4221     Node* log_addr = __ AddP(no_base, buffer, next_index);
4222 
4223     // Order, see storeCM.
4224     __ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
4225     __ store(__ ctrl(), index_adr, next_index, TypeX_X->basic_type(), Compile::AliasIdxRaw, MemNode::unordered);
4226 
4227   } __ else_(); {
4228     __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread());
4229   } __ end_if();
4230 
4231 }
4232 
4233 void GraphKit::g1_write_barrier_post(Node* oop_store,
4234                                      Node* obj,
4235                                      Node* adr,
4236                                      uint alias_idx,
4237                                      Node* val,
4238                                      BasicType bt,
4239                                      bool use_precise) {
4240   // If we are writing a NULL then we need no post barrier
4241 
4242   if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) {
4243     // Must be NULL
4244     const Type* t = val->bottom_type();
4245     assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL");
4246     // No post barrier if writing NULLx
4247     return;
4248   }
4249 
4250   if (use_ReduceInitialCardMarks() && obj == just_allocated_object(control())) {
4251     // We can skip marks on a freshly-allocated object in Eden.
4252     // Keep this code in sync with new_store_pre_barrier() in runtime.cpp.
4253     // That routine informs GC to take appropriate compensating steps,
4254     // upon a slow-path allocation, so as to make this card-mark
4255     // elision safe.
4256     return;
4257   }
4258 
4259   if (use_ReduceInitialCardMarks()
4260       && g1_can_remove_post_barrier(&_gvn, oop_store, adr)) {
4261     return;
4262   }
4263 
4264   if (!use_precise) {
4265     // All card marks for a (non-array) instance are in one place:
4266     adr = obj;
4267   }
4268   // (Else it's an array (or unknown), and we want more precise card marks.)
4269   assert(adr != NULL, "");
4270 
4271   IdealKit ideal(this, true);
4272 
4273   Node* tls = __ thread(); // ThreadLocalStorage
4274 
4275   Node* no_base = __ top();
4276   float likely  = PROB_LIKELY(0.999);
4277   float unlikely  = PROB_UNLIKELY(0.999);
4278   Node* young_card = __ ConI((jint)G1SATBCardTableModRefBS::g1_young_card_val());
4279   Node* dirty_card = __ ConI((jint)CardTableModRefBS::dirty_card_val());
4280   Node* zeroX = __ ConX(0);
4281 
4282   // Get the alias_index for raw card-mark memory
4283   const TypePtr* card_type = TypeRawPtr::BOTTOM;
4284 
4285   const TypeFunc *tf = OptoRuntime::g1_wb_post_Type();
4286 
4287   // Offsets into the thread
4288   const int index_offset  = in_bytes(JavaThread::dirty_card_queue_offset() +
4289                                      DirtyCardQueue::byte_offset_of_index());
4290   const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
4291                                      DirtyCardQueue::byte_offset_of_buf());
4292 
4293   // Pointers into the thread
4294 
4295   Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
4296   Node* index_adr =  __ AddP(no_base, tls, __ ConX(index_offset));
4297 
4298   // Now some values
4299   // Use ctrl to avoid hoisting these values past a safepoint, which could
4300   // potentially reset these fields in the JavaThread.
4301   Node* index  = __ load(__ ctrl(), index_adr, TypeX_X, TypeX_X->basic_type(), Compile::AliasIdxRaw);
4302   Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
4303 
4304   // Convert the store obj pointer to an int prior to doing math on it
4305   // Must use ctrl to prevent "integerized oop" existing across safepoint
4306   Node* cast =  __ CastPX(__ ctrl(), adr);
4307 
4308   // Divide pointer by card size
4309   Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
4310 
4311   // Combine card table base and card offset
4312   Node* card_adr = __ AddP(no_base, byte_map_base_node(), card_offset );
4313 
4314   // If we know the value being stored does it cross regions?
4315 
4316   if (val != NULL) {
4317     // Does the store cause us to cross regions?
4318 
4319     // Should be able to do an unsigned compare of region_size instead of
4320     // and extra shift. Do we have an unsigned compare??
4321     // Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes);
4322     Node* xor_res =  __ URShiftX ( __ XorX( cast,  __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes));
4323 
4324     // if (xor_res == 0) same region so skip
4325     __ if_then(xor_res, BoolTest::ne, zeroX); {
4326 
4327       // No barrier if we are storing a NULL
4328       __ if_then(val, BoolTest::ne, null(), unlikely); {
4329 
4330         // Ok must mark the card if not already dirty
4331 
4332         // load the original value of the card
4333         Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4334 
4335         __ if_then(card_val, BoolTest::ne, young_card); {
4336           sync_kit(ideal);
4337           // Use Op_MemBarVolatile to achieve the effect of a StoreLoad barrier.
4338           insert_mem_bar(Op_MemBarVolatile, oop_store);
4339           __ sync_kit(this);
4340 
4341           Node* card_val_reload = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4342           __ if_then(card_val_reload, BoolTest::ne, dirty_card); {
4343             g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4344           } __ end_if();
4345         } __ end_if();
4346       } __ end_if();
4347     } __ end_if();
4348   } else {
4349     // The Object.clone() intrinsic uses this path if !ReduceInitialCardMarks.
4350     // We don't need a barrier here if the destination is a newly allocated object
4351     // in Eden. Otherwise, GC verification breaks because we assume that cards in Eden
4352     // are set to 'g1_young_gen' (see G1SATBCardTableModRefBS::verify_g1_young_region()).
4353     assert(!use_ReduceInitialCardMarks(), "can only happen with card marking");
4354     Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4355     __ if_then(card_val, BoolTest::ne, young_card); {
4356       g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4357     } __ end_if();
4358   }
4359 
4360   // Final sync IdealKit and GraphKit.
4361   final_sync(ideal);
4362 }
4363 #undef __
4364 
4365 
4366 Node* GraphKit::load_String_length(Node* ctrl, Node* str) {
4367   Node* len = load_array_length(load_String_value(ctrl, str));
4368   Node* coder = load_String_coder(ctrl, str);
4369   // Divide length by 2 if coder is UTF16
4370   return _gvn.transform(new RShiftINode(len, coder));
4371 }
4372 
4373 Node* GraphKit::load_String_value(Node* ctrl, Node* str) {
4374   int value_offset = java_lang_String::value_offset_in_bytes();
4375   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4376                                                      false, NULL, 0);
4377   const TypePtr* value_field_type = string_type->add_offset(value_offset);
4378   const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
4379                                                   TypeAry::make(TypeInt::BYTE, TypeInt::POS),
4380                                                   ciTypeArrayKlass::make(T_BYTE), true, 0);
4381   int value_field_idx = C->get_alias_index(value_field_type);
4382   Node* load = make_load(ctrl, basic_plus_adr(str, str, value_offset),
4383                          value_type, T_OBJECT, value_field_idx, MemNode::unordered);
4384   // String.value field is known to be @Stable.
4385   if (UseImplicitStableValues) {
4386     load = cast_array_to_stable(load, value_type);
4387   }
4388   return load;
4389 }
4390 
4391 Node* GraphKit::load_String_coder(Node* ctrl, Node* str) {
4392   if (!CompactStrings) {
4393     return intcon(java_lang_String::CODER_UTF16);
4394   }
4395   int coder_offset = java_lang_String::coder_offset_in_bytes();
4396   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4397                                                      false, NULL, 0);
4398   const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4399   int coder_field_idx = C->get_alias_index(coder_field_type);
4400   return make_load(ctrl, basic_plus_adr(str, str, coder_offset),
4401                    TypeInt::BYTE, T_BYTE, coder_field_idx, MemNode::unordered);
4402 }
4403 
4404 void GraphKit::store_String_value(Node* ctrl, Node* str, Node* value) {
4405   int value_offset = java_lang_String::value_offset_in_bytes();
4406   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4407                                                      false, NULL, 0);
4408   const TypePtr* value_field_type = string_type->add_offset(value_offset);
4409   store_oop_to_object(ctrl, str,  basic_plus_adr(str, value_offset), value_field_type,
4410       value, TypeAryPtr::BYTES, T_OBJECT, MemNode::unordered);
4411 }
4412 
4413 void GraphKit::store_String_coder(Node* ctrl, Node* str, Node* value) {
4414   int coder_offset = java_lang_String::coder_offset_in_bytes();
4415   const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4416                                                      false, NULL, 0);
4417   const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4418   int coder_field_idx = C->get_alias_index(coder_field_type);
4419   store_to_memory(ctrl, basic_plus_adr(str, coder_offset),
4420                   value, T_BYTE, coder_field_idx, MemNode::unordered);
4421 }
4422 
4423 // Capture src and dst memory state with a MergeMemNode
4424 Node* GraphKit::capture_memory(const TypePtr* src_type, const TypePtr* dst_type) {
4425   if (src_type == dst_type) {
4426     // Types are equal, we don't need a MergeMemNode
4427     return memory(src_type);
4428   }
4429   MergeMemNode* merge = MergeMemNode::make(map()->memory());
4430   record_for_igvn(merge); // fold it up later, if possible
4431   int src_idx = C->get_alias_index(src_type);
4432   int dst_idx = C->get_alias_index(dst_type);
4433   merge->set_memory_at(src_idx, memory(src_idx));
4434   merge->set_memory_at(dst_idx, memory(dst_idx));
4435   return merge;
4436 }
4437 
4438 Node* GraphKit::compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count) {
4439   assert(Matcher::match_rule_supported(Op_StrCompressedCopy), "Intrinsic not supported");
4440   assert(src_type == TypeAryPtr::BYTES || src_type == TypeAryPtr::CHARS, "invalid source type");
4441   // If input and output memory types differ, capture both states to preserve
4442   // the dependency between preceding and subsequent loads/stores.
4443   // For example, the following program:
4444   //  StoreB
4445   //  compress_string
4446   //  LoadB
4447   // has this memory graph (use->def):
4448   //  LoadB -> compress_string -> CharMem
4449   //             ... -> StoreB -> ByteMem
4450   // The intrinsic hides the dependency between LoadB and StoreB, causing
4451   // the load to read from memory not containing the result of the StoreB.
4452   // The correct memory graph should look like this:
4453   //  LoadB -> compress_string -> MergeMem(CharMem, StoreB(ByteMem))
4454   Node* mem = capture_memory(src_type, TypeAryPtr::BYTES);
4455   StrCompressedCopyNode* str = new StrCompressedCopyNode(control(), mem, src, dst, count);
4456   Node* res_mem = _gvn.transform(new SCMemProjNode(str));
4457   set_memory(res_mem, TypeAryPtr::BYTES);
4458   return str;
4459 }
4460 
4461 void GraphKit::inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count) {
4462   assert(Matcher::match_rule_supported(Op_StrInflatedCopy), "Intrinsic not supported");
4463   assert(dst_type == TypeAryPtr::BYTES || dst_type == TypeAryPtr::CHARS, "invalid dest type");
4464   // Capture src and dst memory (see comment in 'compress_string').
4465   Node* mem = capture_memory(TypeAryPtr::BYTES, dst_type);
4466   StrInflatedCopyNode* str = new StrInflatedCopyNode(control(), mem, src, dst, count);
4467   set_memory(_gvn.transform(str), dst_type);
4468 }
4469 
4470 void GraphKit::inflate_string_slow(Node* src, Node* dst, Node* start, Node* count) {
4471   /**
4472    * int i_char = start;
4473    * for (int i_byte = 0; i_byte < count; i_byte++) {
4474    *   dst[i_char++] = (char)(src[i_byte] & 0xff);
4475    * }
4476    */
4477   add_predicate();
4478   RegionNode* head = new RegionNode(3);
4479   head->init_req(1, control());
4480   gvn().set_type(head, Type::CONTROL);
4481   record_for_igvn(head);
4482 
4483   Node* i_byte = new PhiNode(head, TypeInt::INT);
4484   i_byte->init_req(1, intcon(0));
4485   gvn().set_type(i_byte, TypeInt::INT);
4486   record_for_igvn(i_byte);
4487 
4488   Node* i_char = new PhiNode(head, TypeInt::INT);
4489   i_char->init_req(1, start);
4490   gvn().set_type(i_char, TypeInt::INT);
4491   record_for_igvn(i_char);
4492 
4493   Node* mem = PhiNode::make(head, memory(TypeAryPtr::BYTES), Type::MEMORY, TypeAryPtr::BYTES);
4494   gvn().set_type(mem, Type::MEMORY);
4495   record_for_igvn(mem);
4496   set_control(head);
4497   set_memory(mem, TypeAryPtr::BYTES);
4498   Node* ch = load_array_element(control(), src, i_byte, TypeAryPtr::BYTES);
4499   Node* st = store_to_memory(control(), array_element_address(dst, i_char, T_BYTE),
4500                              AndI(ch, intcon(0xff)), T_CHAR, TypeAryPtr::BYTES, MemNode::unordered,
4501                              false, false, true /* mismatched */);
4502 
4503   IfNode* iff = create_and_map_if(head, Bool(CmpI(i_byte, count), BoolTest::lt), PROB_FAIR, COUNT_UNKNOWN);
4504   head->init_req(2, IfTrue(iff));
4505   mem->init_req(2, st);
4506   i_byte->init_req(2, AddI(i_byte, intcon(1)));
4507   i_char->init_req(2, AddI(i_char, intcon(2)));
4508 
4509   set_control(IfFalse(iff));
4510   set_memory(st, TypeAryPtr::BYTES);
4511 }
4512 
4513 Node* GraphKit::make_constant_from_field(ciField* field, Node* obj) {
4514   if (!field->is_constant()) {
4515     return NULL; // Field not marked as constant.
4516   }
4517   ciInstance* holder = NULL;
4518   if (!field->is_static()) {
4519     ciObject* const_oop = obj->bottom_type()->is_oopptr()->const_oop();
4520     if (const_oop != NULL && const_oop->is_instance()) {
4521       holder = const_oop->as_instance();
4522     }
4523   }
4524   const Type* con_type = Type::make_constant_from_field(field, holder, field->layout_type(),
4525                                                         /*is_unsigned_load=*/false);
4526   if (con_type != NULL) {
4527     return makecon(con_type);
4528   }
4529   return NULL;
4530 }
4531 
4532 Node* GraphKit::cast_array_to_stable(Node* ary, const TypeAryPtr* ary_type) {
4533   // Reify the property as a CastPP node in Ideal graph to comply with monotonicity
4534   // assumption of CCP analysis.
4535   return _gvn.transform(new CastPPNode(ary, ary_type->cast_to_stable(true)));









































4536 }
--- EOF ---