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.
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  23  */
  24 
  25 #ifndef SHARE_VM_OPTO_GRAPHKIT_HPP
  26 #define SHARE_VM_OPTO_GRAPHKIT_HPP
  27 
  28 #include "ci/ciEnv.hpp"
  29 #include "ci/ciMethodData.hpp"
  30 #include "gc/shared/c2/barrierSetC2.hpp"
  31 #include "opto/addnode.hpp"
  32 #include "opto/callnode.hpp"
  33 #include "opto/cfgnode.hpp"
  34 #include "opto/compile.hpp"
  35 #include "opto/divnode.hpp"
  36 #include "opto/mulnode.hpp"
  37 #include "opto/phaseX.hpp"
  38 #include "opto/subnode.hpp"
  39 #include "opto/type.hpp"
  40 #include "runtime/deoptimization.hpp"
  41 
  42 class BarrierSetC2;
  43 class FastLockNode;
  44 class FastUnlockNode;
  45 class IdealKit;
  46 class LibraryCallKit;
  47 class Parse;
  48 class RootNode;
  49 
  50 //-----------------------------------------------------------------------------
  51 //----------------------------GraphKit-----------------------------------------
  52 // Toolkit for building the common sorts of subgraphs.
  53 // Does not know about bytecode parsing or type-flow results.
  54 // It is able to create graphs implementing the semantics of most
  55 // or all bytecodes, so that it can expand intrinsics and calls.
  56 // It may depend on JVMState structure, but it must not depend
  57 // on specific bytecode streams.
  58 class GraphKit : public Phase {
  59   friend class PreserveJVMState;
  60 
  61  protected:
  62   ciEnv*            _env;       // Compilation environment
  63   PhaseGVN         &_gvn;       // Some optimizations while parsing
  64   SafePointNode*    _map;       // Parser map from JVM to Nodes
  65   SafePointNode*    _exceptions;// Parser map(s) for exception state(s)
  66   int               _bci;       // JVM Bytecode Pointer
  67   ciMethod*         _method;    // JVM Current Method
  68   BarrierSetC2*     _barrier_set;
  69 #ifdef ASSERT
  70   uint              _worklist_size;
  71 #endif
  72 
  73  private:
  74   int               _sp;        // JVM Expression Stack Pointer; don't modify directly!
  75 
  76  private:
  77   SafePointNode*     map_not_null() const {
  78     assert(_map != NULL, "must call stopped() to test for reset compiler map");
  79     return _map;
  80   }
  81 
  82  public:
  83   GraphKit();                   // empty constructor
  84   GraphKit(JVMState* jvms, PhaseGVN* gvn = NULL);     // the JVM state on which to operate
  85 
  86 #ifdef ASSERT
  87   ~GraphKit() {
  88     assert(!has_exceptions(), "user must call transfer_exceptions_into_jvms");
  89     // During incremental inlining, the Node_Array of the C->for_igvn() worklist and the IGVN
  90     // worklist are shared but the _in_worklist VectorSet is not. To avoid inconsistencies,
  91     // we should not add nodes to the _for_igvn worklist when using IGVN for the GraphKit.
  92     assert((_gvn.is_IterGVN() == NULL) || (_gvn.C->for_igvn()->size() == _worklist_size),
  93            "GraphKit should not modify _for_igvn worklist after parsing");
  94   }
  95 #endif
  96 
  97   virtual Parse*          is_Parse()          const { return NULL; }
  98   virtual LibraryCallKit* is_LibraryCallKit() const { return NULL; }
  99 
 100   ciEnv*        env()               const { return _env; }
 101   PhaseGVN&     gvn()               const { return _gvn; }
 102   void*         barrier_set_state() const { return C->barrier_set_state(); }
 103 
 104   void record_for_igvn(Node* n) const { _gvn.record_for_igvn(n); }
 105 
 106   // Handy well-known nodes:
 107   Node*         null()          const { return zerocon(T_OBJECT); }
 108   Node*         top()           const { return C->top(); }
 109   RootNode*     root()          const { return C->root(); }
 110 
 111   // Create or find a constant node
 112   Node* intcon(jint con)        const { return _gvn.intcon(con); }
 113   Node* longcon(jlong con)      const { return _gvn.longcon(con); }
 114   Node* makecon(const Type *t)  const { return _gvn.makecon(t); }
 115   Node* zerocon(BasicType bt)   const { return _gvn.zerocon(bt); }
 116   // (See also macro MakeConX in type.hpp, which uses intcon or longcon.)
 117 
 118   jint  find_int_con(Node* n, jint value_if_unknown) {
 119     return _gvn.find_int_con(n, value_if_unknown);
 120   }
 121   jlong find_long_con(Node* n, jlong value_if_unknown) {
 122     return _gvn.find_long_con(n, value_if_unknown);
 123   }
 124   // (See also macro find_intptr_t_con in type.hpp, which uses one of these.)
 125 
 126   // JVM State accessors:
 127   // Parser mapping from JVM indices into Nodes.
 128   // Low slots are accessed by the StartNode::enum.
 129   // Then come the locals at StartNode::Parms to StartNode::Parms+max_locals();
 130   // Then come JVM stack slots.
 131   // Finally come the monitors, if any.
 132   // See layout accessors in class JVMState.
 133 
 134   SafePointNode*     map()      const { return _map; }
 135   bool               has_exceptions() const { return _exceptions != NULL; }
 136   JVMState*          jvms()     const { return map_not_null()->_jvms; }
 137   int                sp()       const { return _sp; }
 138   int                bci()      const { return _bci; }
 139   Bytecodes::Code    java_bc()  const;
 140   ciMethod*          method()   const { return _method; }
 141 
 142   void set_jvms(JVMState* jvms)       { set_map(jvms->map());
 143                                         assert(jvms == this->jvms(), "sanity");
 144                                         _sp = jvms->sp();
 145                                         _bci = jvms->bci();
 146                                         _method = jvms->has_method() ? jvms->method() : NULL; }
 147   void set_map(SafePointNode* m)      { _map = m; debug_only(verify_map()); }
 148   void set_sp(int sp)                 { assert(sp >= 0, "sp must be non-negative: %d", sp); _sp = sp; }
 149   void clean_stack(int from_sp); // clear garbage beyond from_sp to top
 150 
 151   void inc_sp(int i)                  { set_sp(sp() + i); }
 152   void dec_sp(int i)                  { set_sp(sp() - i); }
 153   void set_bci(int bci)               { _bci = bci; }
 154 
 155   // Make sure jvms has current bci & sp.
 156   JVMState* sync_jvms() const;
 157   JVMState* sync_jvms_for_reexecute();
 158 
 159 #ifdef ASSERT
 160   // Make sure JVMS has an updated copy of bci and sp.
 161   // Also sanity-check method, depth, and monitor depth.
 162   bool jvms_in_sync() const;
 163 
 164   // Make sure the map looks OK.
 165   void verify_map() const;
 166 
 167   // Make sure a proposed exception state looks OK.
 168   static void verify_exception_state(SafePointNode* ex_map);
 169 #endif
 170 
 171   // Clone the existing map state.  (Implements PreserveJVMState.)
 172   SafePointNode* clone_map();
 173 
 174   // Set the map to a clone of the given one.
 175   void set_map_clone(SafePointNode* m);
 176 
 177   // Tell if the compilation is failing.
 178   bool failing() const { return C->failing(); }
 179 
 180   // Set _map to NULL, signalling a stop to further bytecode execution.
 181   // Preserve the map intact for future use, and return it back to the caller.
 182   SafePointNode* stop() { SafePointNode* m = map(); set_map(NULL); return m; }
 183 
 184   // Stop, but first smash the map's inputs to NULL, to mark it dead.
 185   void stop_and_kill_map();
 186 
 187   // Tell if _map is NULL, or control is top.
 188   bool stopped();
 189 
 190   // Tell if this method or any caller method has exception handlers.
 191   bool has_ex_handler();
 192 
 193   // Save an exception without blowing stack contents or other JVM state.
 194   // (The extra pointer is stuck with add_req on the map, beyond the JVMS.)
 195   static void set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop);
 196 
 197   // Recover a saved exception from its map.
 198   static Node* saved_ex_oop(SafePointNode* ex_map);
 199 
 200   // Recover a saved exception from its map, and remove it from the map.
 201   static Node* clear_saved_ex_oop(SafePointNode* ex_map);
 202 
 203 #ifdef ASSERT
 204   // Recover a saved exception from its map, and remove it from the map.
 205   static bool has_saved_ex_oop(SafePointNode* ex_map);
 206 #endif
 207 
 208   // Push an exception in the canonical position for handlers (stack(0)).
 209   void push_ex_oop(Node* ex_oop) {
 210     ensure_stack(1);  // ensure room to push the exception
 211     set_stack(0, ex_oop);
 212     set_sp(1);
 213     clean_stack(1);
 214   }
 215 
 216   // Detach and return an exception state.
 217   SafePointNode* pop_exception_state() {
 218     SafePointNode* ex_map = _exceptions;
 219     if (ex_map != NULL) {
 220       _exceptions = ex_map->next_exception();
 221       ex_map->set_next_exception(NULL);
 222       debug_only(verify_exception_state(ex_map));
 223     }
 224     return ex_map;
 225   }
 226 
 227   // Add an exception, using the given JVM state, without commoning.
 228   void push_exception_state(SafePointNode* ex_map) {
 229     debug_only(verify_exception_state(ex_map));
 230     ex_map->set_next_exception(_exceptions);
 231     _exceptions = ex_map;
 232   }
 233 
 234   // Turn the current JVM state into an exception state, appending the ex_oop.
 235   SafePointNode* make_exception_state(Node* ex_oop);
 236 
 237   // Add an exception, using the given JVM state.
 238   // Combine all exceptions with a common exception type into a single state.
 239   // (This is done via combine_exception_states.)
 240   void add_exception_state(SafePointNode* ex_map);
 241 
 242   // Combine all exceptions of any sort whatever into a single master state.
 243   SafePointNode* combine_and_pop_all_exception_states() {
 244     if (_exceptions == NULL)  return NULL;
 245     SafePointNode* phi_map = pop_exception_state();
 246     SafePointNode* ex_map;
 247     while ((ex_map = pop_exception_state()) != NULL) {
 248       combine_exception_states(ex_map, phi_map);
 249     }
 250     return phi_map;
 251   }
 252 
 253   // Combine the two exception states, building phis as necessary.
 254   // The second argument is updated to include contributions from the first.
 255   void combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map);
 256 
 257   // Reset the map to the given state.  If there are any half-finished phis
 258   // in it (created by combine_exception_states), transform them now.
 259   // Returns the exception oop.  (Caller must call push_ex_oop if required.)
 260   Node* use_exception_state(SafePointNode* ex_map);
 261 
 262   // Collect exceptions from a given JVM state into my exception list.
 263   void add_exception_states_from(JVMState* jvms);
 264 
 265   // Collect all raised exceptions into the current JVM state.
 266   // Clear the current exception list and map, returns the combined states.
 267   JVMState* transfer_exceptions_into_jvms();
 268 
 269   // Helper to throw a built-in exception.
 270   // Range checks take the offending index.
 271   // Cast and array store checks take the offending class.
 272   // Others do not take the optional argument.
 273   // The JVMS must allow the bytecode to be re-executed
 274   // via an uncommon trap.
 275   void builtin_throw(Deoptimization::DeoptReason reason, Node* arg = NULL);
 276 
 277   // Helper to check the JavaThread::_should_post_on_exceptions flag
 278   // and branch to an uncommon_trap if it is true (with the specified reason and must_throw)
 279   void uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
 280                                                   bool must_throw) ;
 281 
 282   // Helper Functions for adding debug information
 283   void kill_dead_locals();
 284 #ifdef ASSERT
 285   bool dead_locals_are_killed();
 286 #endif
 287   // The call may deoptimize.  Supply required JVM state as debug info.
 288   // If must_throw is true, the call is guaranteed not to return normally.
 289   void add_safepoint_edges(SafePointNode* call,
 290                            bool must_throw = false);
 291 
 292   // How many stack inputs does the current BC consume?
 293   // And, how does the stack change after the bytecode?
 294   // Returns false if unknown.
 295   bool compute_stack_effects(int& inputs, int& depth);
 296 
 297   // Add a fixed offset to a pointer
 298   Node* basic_plus_adr(Node* base, Node* ptr, intptr_t offset) {
 299     return basic_plus_adr(base, ptr, MakeConX(offset));
 300   }
 301   Node* basic_plus_adr(Node* base, intptr_t offset) {
 302     return basic_plus_adr(base, base, MakeConX(offset));
 303   }
 304   // Add a variable offset to a pointer
 305   Node* basic_plus_adr(Node* base, Node* offset) {
 306     return basic_plus_adr(base, base, offset);
 307   }
 308   Node* basic_plus_adr(Node* base, Node* ptr, Node* offset);
 309 
 310 
 311   // Some convenient shortcuts for common nodes
 312   Node* IfTrue(IfNode* iff)                   { return _gvn.transform(new IfTrueNode(iff));      }
 313   Node* IfFalse(IfNode* iff)                  { return _gvn.transform(new IfFalseNode(iff));     }
 314 
 315   Node* AddI(Node* l, Node* r)                { return _gvn.transform(new AddINode(l, r));       }
 316   Node* SubI(Node* l, Node* r)                { return _gvn.transform(new SubINode(l, r));       }
 317   Node* MulI(Node* l, Node* r)                { return _gvn.transform(new MulINode(l, r));       }
 318   Node* DivI(Node* ctl, Node* l, Node* r)     { return _gvn.transform(new DivINode(ctl, l, r));  }
 319 
 320   Node* AndI(Node* l, Node* r)                { return _gvn.transform(new AndINode(l, r));       }
 321   Node* OrI(Node* l, Node* r)                 { return _gvn.transform(new OrINode(l, r));        }
 322   Node* XorI(Node* l, Node* r)                { return _gvn.transform(new XorINode(l, r));       }
 323 
 324   Node* MaxI(Node* l, Node* r)                { return _gvn.transform(new MaxINode(l, r));       }
 325   Node* MinI(Node* l, Node* r)                { return _gvn.transform(new MinINode(l, r));       }
 326 
 327   Node* LShiftI(Node* l, Node* r)             { return _gvn.transform(new LShiftINode(l, r));    }
 328   Node* RShiftI(Node* l, Node* r)             { return _gvn.transform(new RShiftINode(l, r));    }
 329   Node* URShiftI(Node* l, Node* r)            { return _gvn.transform(new URShiftINode(l, r));   }
 330 
 331   Node* CmpI(Node* l, Node* r)                { return _gvn.transform(new CmpINode(l, r));       }
 332   Node* CmpL(Node* l, Node* r)                { return _gvn.transform(new CmpLNode(l, r));       }
 333   Node* CmpP(Node* l, Node* r)                { return _gvn.transform(new CmpPNode(l, r));       }
 334   Node* Bool(Node* cmp, BoolTest::mask relop) { return _gvn.transform(new BoolNode(cmp, relop)); }
 335 
 336   Node* AddP(Node* b, Node* a, Node* o)       { return _gvn.transform(new AddPNode(b, a, o));    }
 337 
 338   // Convert between int and long, and size_t.
 339   // (See macros ConvI2X, etc., in type.hpp for ConvI2X, etc.)
 340   Node* ConvI2L(Node* offset);
 341   Node* ConvI2UL(Node* offset);
 342   Node* ConvL2I(Node* offset);
 343   // Find out the klass of an object.
 344   Node* load_object_klass(Node* object);
 345   // Find out the length of an array.
 346   Node* load_array_length(Node* array);
 347 
 348 
 349   // Helper function to do a NULL pointer check or ZERO check based on type.
 350   // Throw an exception if a given value is null.
 351   // Return the value cast to not-null.
 352   // Be clever about equivalent dominating null checks.
 353   Node* null_check_common(Node* value, BasicType type,
 354                           bool assert_null = false,
 355                           Node* *null_control = NULL,
 356                           bool speculative = false);
 357   Node* null_check(Node* value, BasicType type = T_OBJECT) {
 358     return null_check_common(value, type, false, NULL, !_gvn.type(value)->speculative_maybe_null());
 359   }
 360   Node* null_check_receiver() {
 361     assert(argument(0)->bottom_type()->isa_ptr(), "must be");
 362     return null_check(argument(0));
 363   }
 364   Node* zero_check_int(Node* value) {
 365     assert(value->bottom_type()->basic_type() == T_INT,
 366            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
 367     return null_check_common(value, T_INT);
 368   }
 369   Node* zero_check_long(Node* value) {
 370     assert(value->bottom_type()->basic_type() == T_LONG,
 371            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
 372     return null_check_common(value, T_LONG);
 373   }
 374   // Throw an uncommon trap if a given value is __not__ null.
 375   // Return the value cast to null, and be clever about dominating checks.
 376   Node* null_assert(Node* value, BasicType type = T_OBJECT) {
 377     return null_check_common(value, type, true, NULL, _gvn.type(value)->speculative_always_null());
 378   }
 379 
 380   // Check if value is null and abort if it is
 381   Node* must_be_not_null(Node* value, bool do_replace_in_map);
 382 
 383   // Null check oop.  Return null-path control into (*null_control).
 384   // Return a cast-not-null node which depends on the not-null control.
 385   // If never_see_null, use an uncommon trap (*null_control sees a top).
 386   // The cast is not valid along the null path; keep a copy of the original.
 387   // If safe_for_replace, then we can replace the value with the cast
 388   // in the parsing map (the cast is guaranteed to dominate the map)
 389   Node* null_check_oop(Node* value, Node* *null_control,
 390                        bool never_see_null = false,
 391                        bool safe_for_replace = false,
 392                        bool speculative = false);
 393 
 394   // Check the null_seen bit.
 395   bool seems_never_null(Node* obj, ciProfileData* data, bool& speculating);
 396 
 397   // Check for unique class for receiver at call
 398   ciKlass* profile_has_unique_klass() {
 399     ciCallProfile profile = method()->call_profile_at_bci(bci());
 400     if (profile.count() >= 0 &&         // no cast failures here
 401         profile.has_receiver(0) &&
 402         profile.morphism() == 1) {
 403       return profile.receiver(0);
 404     }
 405     return NULL;
 406   }
 407 
 408   // record type from profiling with the type system
 409   Node* record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind);
 410   void record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc);
 411   void record_profiled_parameters_for_speculation();
 412   void record_profiled_return_for_speculation();
 413   Node* record_profiled_receiver_for_speculation(Node* n);
 414 
 415   // Use the type profile to narrow an object type.
 416   Node* maybe_cast_profiled_receiver(Node* not_null_obj,
 417                                      ciKlass* require_klass,
 418                                      ciKlass* spec,
 419                                      bool safe_for_replace);
 420 
 421   // Cast obj to type and emit guard unless we had too many traps here already
 422   Node* maybe_cast_profiled_obj(Node* obj,
 423                                 ciKlass* type,
 424                                 bool not_null = false);
 425 
 426   // Cast obj to not-null on this path
 427   Node* cast_not_null(Node* obj, bool do_replace_in_map = true);
 428   // Replace all occurrences of one node by another.
 429   void replace_in_map(Node* old, Node* neww);
 430 
 431   void  push(Node* n)     { map_not_null();        _map->set_stack(_map->_jvms,   _sp++        , n); }
 432   Node* pop()             { map_not_null(); return _map->stack(    _map->_jvms, --_sp             ); }
 433   Node* peek(int off = 0) { map_not_null(); return _map->stack(    _map->_jvms,   _sp - off - 1   ); }
 434 
 435   void push_pair(Node* ldval) {
 436     push(ldval);
 437     push(top());  // the halfword is merely a placeholder
 438   }
 439   void push_pair_local(int i) {
 440     // longs are stored in locals in "push" order
 441     push(  local(i+0) );  // the real value
 442     assert(local(i+1) == top(), "");
 443     push(top());  // halfword placeholder
 444   }
 445   Node* pop_pair() {
 446     // the second half is pushed last & popped first; it contains exactly nothing
 447     Node* halfword = pop();
 448     assert(halfword == top(), "");
 449     // the long bits are pushed first & popped last:
 450     return pop();
 451   }
 452   void set_pair_local(int i, Node* lval) {
 453     // longs are stored in locals as a value/half pair (like doubles)
 454     set_local(i+0, lval);
 455     set_local(i+1, top());
 456   }
 457 
 458   // Push the node, which may be zero, one, or two words.
 459   void push_node(BasicType n_type, Node* n) {
 460     int n_size = type2size[n_type];
 461     if      (n_size == 1)  push(      n );  // T_INT, ...
 462     else if (n_size == 2)  push_pair( n );  // T_DOUBLE, T_LONG
 463     else                   { assert(n_size == 0, "must be T_VOID"); }
 464   }
 465 
 466   Node* pop_node(BasicType n_type) {
 467     int n_size = type2size[n_type];
 468     if      (n_size == 1)  return pop();
 469     else if (n_size == 2)  return pop_pair();
 470     else                   return NULL;
 471   }
 472 
 473   Node* control()               const { return map_not_null()->control(); }
 474   Node* i_o()                   const { return map_not_null()->i_o(); }
 475   Node* returnadr()             const { return map_not_null()->returnadr(); }
 476   Node* frameptr()              const { return map_not_null()->frameptr(); }
 477   Node* local(uint idx)         const { map_not_null(); return _map->local(      _map->_jvms, idx); }
 478   Node* stack(uint idx)         const { map_not_null(); return _map->stack(      _map->_jvms, idx); }
 479   Node* argument(uint idx)      const { map_not_null(); return _map->argument(   _map->_jvms, idx); }
 480   Node* monitor_box(uint idx)   const { map_not_null(); return _map->monitor_box(_map->_jvms, idx); }
 481   Node* monitor_obj(uint idx)   const { map_not_null(); return _map->monitor_obj(_map->_jvms, idx); }
 482 
 483   void set_control  (Node* c)         { map_not_null()->set_control(c); }
 484   void set_i_o      (Node* c)         { map_not_null()->set_i_o(c); }
 485   void set_local(uint idx, Node* c)   { map_not_null(); _map->set_local(   _map->_jvms, idx, c); }
 486   void set_stack(uint idx, Node* c)   { map_not_null(); _map->set_stack(   _map->_jvms, idx, c); }
 487   void set_argument(uint idx, Node* c){ map_not_null(); _map->set_argument(_map->_jvms, idx, c); }
 488   void ensure_stack(uint stk_size)    { map_not_null(); _map->ensure_stack(_map->_jvms, stk_size); }
 489 
 490   // Access unaliased memory
 491   Node* memory(uint alias_idx);
 492   Node* memory(const TypePtr *tp) { return memory(C->get_alias_index(tp)); }
 493   Node* memory(Node* adr) { return memory(_gvn.type(adr)->is_ptr()); }
 494 
 495   // Access immutable memory
 496   Node* immutable_memory() { return C->immutable_memory(); }
 497 
 498   // Set unaliased memory
 499   void set_memory(Node* c, uint alias_idx) { merged_memory()->set_memory_at(alias_idx, c); }
 500   void set_memory(Node* c, const TypePtr *tp) { set_memory(c,C->get_alias_index(tp)); }
 501   void set_memory(Node* c, Node* adr) { set_memory(c,_gvn.type(adr)->is_ptr()); }
 502 
 503   // Get the entire memory state (probably a MergeMemNode), and reset it
 504   // (The resetting prevents somebody from using the dangling Node pointer.)
 505   Node* reset_memory();
 506 
 507   // Get the entire memory state, asserted to be a MergeMemNode.
 508   MergeMemNode* merged_memory() {
 509     Node* mem = map_not_null()->memory();
 510     assert(mem->is_MergeMem(), "parse memory is always pre-split");
 511     return mem->as_MergeMem();
 512   }
 513 
 514   // Set the entire memory state; produce a new MergeMemNode.
 515   void set_all_memory(Node* newmem);
 516 
 517   // Create a memory projection from the call, then set_all_memory.
 518   void set_all_memory_call(Node* call, bool separate_io_proj = false);
 519 
 520   // Create a LoadNode, reading from the parser's memory state.
 521   // (Note:  require_atomic_access is useful only with T_LONG.)
 522   //
 523   // We choose the unordered semantics by default because we have
 524   // adapted the `do_put_xxx' and `do_get_xxx' procedures for the case
 525   // of volatile fields.
 526   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
 527                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
 528                   bool require_atomic_access = false, bool unaligned = false,
 529                   bool mismatched = false) {
 530     // This version computes alias_index from bottom_type
 531     return make_load(ctl, adr, t, bt, adr->bottom_type()->is_ptr(),
 532                      mo, control_dependency, require_atomic_access,
 533                      unaligned, mismatched);
 534   }
 535   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, const TypePtr* adr_type,
 536                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
 537                   bool require_atomic_access = false, bool unaligned = false,
 538                   bool mismatched = false) {
 539     // This version computes alias_index from an address type
 540     assert(adr_type != NULL, "use other make_load factory");
 541     return make_load(ctl, adr, t, bt, C->get_alias_index(adr_type),
 542                      mo, control_dependency, require_atomic_access,
 543                      unaligned, mismatched);
 544   }
 545   // This is the base version which is given an alias index.
 546   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, int adr_idx,
 547                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
 548                   bool require_atomic_access = false, bool unaligned = false,
 549                   bool mismatched = false);
 550 
 551   // Create & transform a StoreNode and store the effect into the
 552   // parser's memory state.
 553   //
 554   // We must ensure that stores of object references will be visible
 555   // only after the object's initialization. So the clients of this
 556   // procedure must indicate that the store requires `release'
 557   // semantics, if the stored value is an object reference that might
 558   // point to a new object and may become externally visible.
 559   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
 560                         const TypePtr* adr_type,
 561                         MemNode::MemOrd mo,
 562                         bool require_atomic_access = false,
 563                         bool unaligned = false,
 564                         bool mismatched = false) {
 565     // This version computes alias_index from an address type
 566     assert(adr_type != NULL, "use other store_to_memory factory");
 567     return store_to_memory(ctl, adr, val, bt,
 568                            C->get_alias_index(adr_type),
 569                            mo, require_atomic_access,
 570                            unaligned, mismatched);
 571   }
 572   // This is the base version which is given alias index
 573   // Return the new StoreXNode
 574   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
 575                         int adr_idx,
 576                         MemNode::MemOrd,
 577                         bool require_atomic_access = false,
 578                         bool unaligned = false,
 579                         bool mismatched = false);
 580 
 581   // Perform decorated accesses
 582 
 583   Node* access_store_at(Node* ctl,
 584                         Node* obj,   // containing obj
 585                         Node* adr,   // actual adress to store val at
 586                         const TypePtr* adr_type,
 587                         Node* val,
 588                         const Type* val_type,
 589                         BasicType bt,
 590                         DecoratorSet decorators,
 591                         bool deoptimize_on_exception = false);
 592 
 593   Node* access_load_at(Node* obj,   // containing obj
 594                        Node* adr,   // actual adress to load val at
 595                        const TypePtr* adr_type,
 596                        const Type* val_type,
 597                        BasicType bt,
 598                        DecoratorSet decorators);
 599 
 600   Node* access_load(Node* adr,   // actual adress to load val at
 601                     const Type* val_type,
 602                     BasicType bt,
 603                     DecoratorSet decorators);
 604 
 605   Node* access_atomic_cmpxchg_val_at(Node* ctl,
 606                                      Node* obj,
 607                                      Node* adr,
 608                                      const TypePtr* adr_type,
 609                                      int alias_idx,
 610                                      Node* expected_val,
 611                                      Node* new_val,
 612                                      const Type* value_type,
 613                                      BasicType bt,
 614                                      DecoratorSet decorators);
 615 
 616   Node* access_atomic_cmpxchg_bool_at(Node* ctl,
 617                                       Node* obj,
 618                                       Node* adr,
 619                                       const TypePtr* adr_type,
 620                                       int alias_idx,
 621                                       Node* expected_val,
 622                                       Node* new_val,
 623                                       const Type* value_type,
 624                                       BasicType bt,
 625                                       DecoratorSet decorators);
 626 
 627   Node* access_atomic_xchg_at(Node* ctl,
 628                               Node* obj,
 629                               Node* adr,
 630                               const TypePtr* adr_type,
 631                               int alias_idx,
 632                               Node* new_val,
 633                               const Type* value_type,
 634                               BasicType bt,
 635                               DecoratorSet decorators);
 636 
 637   Node* access_atomic_add_at(Node* ctl,
 638                              Node* obj,
 639                              Node* adr,
 640                              const TypePtr* adr_type,
 641                              int alias_idx,
 642                              Node* new_val,
 643                              const Type* value_type,
 644                              BasicType bt,
 645                              DecoratorSet decorators);
 646 
 647   void access_clone(Node* ctl, Node* src_base, Node* dst_base, Node* countx, bool is_array);
 648 
 649   // Return addressing for an array element.
 650   Node* array_element_address(Node* ary, Node* idx, BasicType elembt,
 651                               // Optional constraint on the array size:
 652                               const TypeInt* sizetype = NULL,
 653                               // Optional control dependency (for example, on range check)
 654                               Node* ctrl = NULL);
 655 
 656   // Return a load of array element at idx.
 657   Node* load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype);
 658 
 659   //---------------- Dtrace support --------------------
 660   void make_dtrace_method_entry_exit(ciMethod* method, bool is_entry);
 661   void make_dtrace_method_entry(ciMethod* method) {
 662     make_dtrace_method_entry_exit(method, true);
 663   }
 664   void make_dtrace_method_exit(ciMethod* method) {
 665     make_dtrace_method_entry_exit(method, false);
 666   }
 667 
 668   //--------------- stub generation -------------------
 669  public:
 670   void gen_stub(address C_function,
 671                 const char *name,
 672                 int is_fancy_jump,
 673                 bool pass_tls,
 674                 bool return_pc);
 675 
 676   //---------- help for generating calls --------------
 677 
 678   // Do a null check on the receiver as it would happen before the call to
 679   // callee (with all arguments still on the stack).
 680   Node* null_check_receiver_before_call(ciMethod* callee) {
 681     assert(!callee->is_static(), "must be a virtual method");
 682     // Callsite signature can be different from actual method being called (i.e _linkTo* sites).
 683     // Use callsite signature always.
 684     ciMethod* declared_method = method()->get_method_at_bci(bci());
 685     const int nargs = declared_method->arg_size();
 686     inc_sp(nargs);
 687     Node* n = null_check_receiver();
 688     dec_sp(nargs);
 689     return n;
 690   }
 691 
 692   // Fill in argument edges for the call from argument(0), argument(1), ...
 693   // (The next step is to call set_edges_for_java_call.)
 694   void  set_arguments_for_java_call(CallJavaNode* call);
 695 
 696   // Fill in non-argument edges for the call.
 697   // Transform the call, and update the basics: control, i_o, memory.
 698   // (The next step is usually to call set_results_for_java_call.)
 699   void set_edges_for_java_call(CallJavaNode* call,
 700                                bool must_throw = false, bool separate_io_proj = false);
 701 
 702   // Finish up a java call that was started by set_edges_for_java_call.
 703   // Call add_exception on any throw arising from the call.
 704   // Return the call result (transformed).
 705   Node* set_results_for_java_call(CallJavaNode* call, bool separate_io_proj = false, bool deoptimize = false);
 706 
 707   // Similar to set_edges_for_java_call, but simplified for runtime calls.
 708   void  set_predefined_output_for_runtime_call(Node* call) {
 709     set_predefined_output_for_runtime_call(call, NULL, NULL);
 710   }
 711   void  set_predefined_output_for_runtime_call(Node* call,
 712                                                Node* keep_mem,
 713                                                const TypePtr* hook_mem);
 714   Node* set_predefined_input_for_runtime_call(SafePointNode* call);
 715 
 716   // Replace the call with the current state of the kit.  Requires
 717   // that the call was generated with separate io_projs so that
 718   // exceptional control flow can be handled properly.
 719   void replace_call(CallNode* call, Node* result, bool do_replaced_nodes = false);
 720 
 721   // helper functions for statistics
 722   void increment_counter(address counter_addr);   // increment a debug counter
 723   void increment_counter(Node*   counter_addr);   // increment a debug counter
 724 
 725   // Bail out to the interpreter right now
 726   // The optional klass is the one causing the trap.
 727   // The optional reason is debug information written to the compile log.
 728   // Optional must_throw is the same as with add_safepoint_edges.
 729   void uncommon_trap(int trap_request,
 730                      ciKlass* klass = NULL, const char* reason_string = NULL,
 731                      bool must_throw = false, bool keep_exact_action = false);
 732 
 733   // Shorthand, to avoid saying "Deoptimization::" so many times.
 734   void uncommon_trap(Deoptimization::DeoptReason reason,
 735                      Deoptimization::DeoptAction action,
 736                      ciKlass* klass = NULL, const char* reason_string = NULL,
 737                      bool must_throw = false, bool keep_exact_action = false) {
 738     uncommon_trap(Deoptimization::make_trap_request(reason, action),
 739                   klass, reason_string, must_throw, keep_exact_action);
 740   }
 741 
 742   // Bail out to the interpreter and keep exact action (avoid switching to Action_none).
 743   void uncommon_trap_exact(Deoptimization::DeoptReason reason,
 744                            Deoptimization::DeoptAction action,
 745                            ciKlass* klass = NULL, const char* reason_string = NULL,
 746                            bool must_throw = false) {
 747     uncommon_trap(Deoptimization::make_trap_request(reason, action),
 748                   klass, reason_string, must_throw, /*keep_exact_action=*/true);
 749   }
 750 
 751   // SP when bytecode needs to be reexecuted.
 752   virtual int reexecute_sp() { return sp(); }
 753 
 754   // Report if there were too many traps at the current method and bci.
 755   // Report if a trap was recorded, and/or PerMethodTrapLimit was exceeded.
 756   // If there is no MDO at all, report no trap unless told to assume it.
 757   bool too_many_traps(Deoptimization::DeoptReason reason) {
 758     return C->too_many_traps(method(), bci(), reason);
 759   }
 760 
 761   // Report if there were too many recompiles at the current method and bci.
 762   bool too_many_recompiles(Deoptimization::DeoptReason reason) {
 763     return C->too_many_recompiles(method(), bci(), reason);
 764   }
 765 
 766   // Returns the object (if any) which was created the moment before.
 767   Node* just_allocated_object(Node* current_control);
 768 
 769   // Sync Ideal and Graph kits.
 770   void sync_kit(IdealKit& ideal);
 771   void final_sync(IdealKit& ideal);
 772 
 773   public:
 774   // Helper function to round double arguments before a call
 775   void round_double_arguments(ciMethod* dest_method);
 776   void round_double_result(ciMethod* dest_method);
 777 
 778   // rounding for strict float precision conformance
 779   Node* precision_rounding(Node* n);
 780 
 781   // rounding for strict double precision conformance
 782   Node* dprecision_rounding(Node* n);
 783 
 784   // rounding for non-strict double stores
 785   Node* dstore_rounding(Node* n);
 786 
 787   // Helper functions for fast/slow path codes
 788   Node* opt_iff(Node* region, Node* iff);
 789   Node* make_runtime_call(int flags,
 790                           const TypeFunc* call_type, address call_addr,
 791                           const char* call_name,
 792                           const TypePtr* adr_type, // NULL if no memory effects
 793                           Node* parm0 = NULL, Node* parm1 = NULL,
 794                           Node* parm2 = NULL, Node* parm3 = NULL,
 795                           Node* parm4 = NULL, Node* parm5 = NULL,
 796                           Node* parm6 = NULL, Node* parm7 = NULL);
 797   enum {  // flag values for make_runtime_call
 798     RC_NO_FP = 1,               // CallLeafNoFPNode
 799     RC_NO_IO = 2,               // do not hook IO edges
 800     RC_NO_LEAF = 4,             // CallStaticJavaNode
 801     RC_MUST_THROW = 8,          // flag passed to add_safepoint_edges
 802     RC_NARROW_MEM = 16,         // input memory is same as output
 803     RC_UNCOMMON = 32,           // freq. expected to be like uncommon trap
 804     RC_LEAF = 0                 // null value:  no flags set
 805   };
 806 
 807   // merge in all memory slices from new_mem, along the given path
 808   void merge_memory(Node* new_mem, Node* region, int new_path);
 809   void make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize = false);
 810 
 811   // Helper functions to build synchronizations
 812   int next_monitor();
 813   Node* insert_mem_bar(int opcode, Node* precedent = NULL);
 814   Node* insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent = NULL);
 815   // Optional 'precedent' is appended as an extra edge, to force ordering.
 816   FastLockNode* shared_lock(Node* obj);
 817   void shared_unlock(Node* box, Node* obj);
 818 
 819   // helper functions for the fast path/slow path idioms
 820   Node* fast_and_slow(Node* in, const Type *result_type, Node* null_result, IfNode* fast_test, Node* fast_result, address slow_call, const TypeFunc *slow_call_type, Node* slow_arg, Klass* ex_klass, Node* slow_result);
 821 
 822   // Generate an instance-of idiom.  Used by both the instance-of bytecode
 823   // and the reflective instance-of call.
 824   Node* gen_instanceof(Node *subobj, Node* superkls, bool safe_for_replace = false);
 825 
 826   // Generate a check-cast idiom.  Used by both the check-cast bytecode
 827   // and the array-store bytecode
 828   Node* gen_checkcast( Node *subobj, Node* superkls,
 829                        Node* *failure_control = NULL );
 830 
 831   Node* is_always_locked(Node* obj);
 832   Node* gen_value_type_test(Node* kls);
 833   void gen_value_type_guard(Node* obj, int nargs = 0);
 834   void gen_value_type_array_guard(Node* ary, Node* obj, Node* elem_klass, int nargs);
 835   void gen_flattened_array_guard(Node* ary, int nargs = 0);
 836   Node* gen_lh_array_test(Node* kls, unsigned int lh_value);
 837 
 838   Node* gen_subtype_check(Node* subklass, Node* superklass) {
 839     MergeMemNode* mem = merged_memory();
 840     Node* ctrl = control();
 841     Node* n = Phase::gen_subtype_check(subklass, superklass, &ctrl, mem, &_gvn);
 842     set_control(ctrl);
 843     return n;
 844   }
 845 
 846   // Exact type check used for predicted calls and casts.
 847   // Rewrites (*casted_receiver) to be casted to the stronger type.
 848   // (Caller is responsible for doing replace_in_map.)
 849   Node* type_check_receiver(Node* receiver, ciKlass* klass, float prob,
 850                             Node* *casted_receiver);
 851   Node* type_check(Node* recv_klass, const TypeKlassPtr* tklass, float prob);
 852 
 853   // implementation of object creation
 854   Node* set_output_for_allocation(AllocateNode* alloc,
 855                                   const TypeOopPtr* oop_type,
 856                                   bool deoptimize_on_exception=false);
 857   Node* get_layout_helper(Node* klass_node, jint& constant_value);
 858   Node* new_instance(Node* klass_node,
 859                      Node* slow_test = NULL,
 860                      Node* *return_size_val = NULL,
 861                      bool deoptimize_on_exception = false,
 862                      ValueTypeBaseNode* value_node = NULL);
 863   Node* new_array(Node* klass_node, Node* count_val, int nargs,
 864                   Node* *return_size_val = NULL,
 865                   bool deoptimize_on_exception = false);
 866 
 867   // java.lang.String helpers
 868   Node* load_String_length(Node* ctrl, Node* str);
 869   Node* load_String_value(Node* ctrl, Node* str);
 870   Node* load_String_coder(Node* ctrl, Node* str);
 871   void store_String_value(Node* ctrl, Node* str, Node* value);
 872   void store_String_coder(Node* ctrl, Node* str, Node* value);
 873   Node* capture_memory(const TypePtr* src_type, const TypePtr* dst_type);
 874   Node* compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count);
 875   void inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count);
 876   void inflate_string_slow(Node* src, Node* dst, Node* start, Node* count);
 877 
 878   // Handy for making control flow
 879   IfNode* create_and_map_if(Node* ctrl, Node* tst, float prob, float cnt) {
 880     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
 881     _gvn.set_type(iff, iff->Value(&_gvn)); // Value may be known at parse-time
 882     // Place 'if' on worklist if it will be in graph
 883     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
 884     return iff;
 885   }
 886 
 887   IfNode* create_and_xform_if(Node* ctrl, Node* tst, float prob, float cnt) {
 888     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
 889     _gvn.transform(iff);                           // Value may be known at parse-time
 890     // Place 'if' on worklist if it will be in graph
 891     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
 892     return iff;
 893   }
 894 
 895   // Insert a loop predicate into the graph
 896   void add_predicate(int nargs = 0);
 897   void add_predicate_impl(Deoptimization::DeoptReason reason, int nargs);
 898 
 899   Node* make_constant_from_field(ciField* field, Node* obj);
 900 
 901   // Produce new array node of stable type
 902   Node* cast_array_to_stable(Node* ary, const TypeAryPtr* ary_type);
 903 
 904   Node* load_mirror_from_klass(Node* klass);
 905 };
 906 
 907 // Helper class to support building of control flow branches. Upon
 908 // creation the map and sp at bci are cloned and restored upon de-
 909 // struction. Typical use:
 910 //
 911 // { PreserveJVMState pjvms(this);
 912 //   // code of new branch
 913 // }
 914 // // here the JVM state at bci is established
 915 
 916 class PreserveJVMState: public StackObj {
 917  protected:
 918   GraphKit*      _kit;
 919 #ifdef ASSERT
 920   int            _block;  // PO of current block, if a Parse
 921   int            _bci;
 922 #endif
 923   SafePointNode* _map;
 924   uint           _sp;
 925 
 926  public:
 927   PreserveJVMState(GraphKit* kit, bool clone_map = true);
 928   ~PreserveJVMState();
 929 };
 930 
 931 // Helper class to build cutouts of the form if (p) ; else {x...}.
 932 // The code {x...} must not fall through.
 933 // The kit's main flow of control is set to the "then" continuation of if(p).
 934 class BuildCutout: public PreserveJVMState {
 935  public:
 936   BuildCutout(GraphKit* kit, Node* p, float prob, float cnt = COUNT_UNKNOWN);
 937   ~BuildCutout();
 938 };
 939 
 940 // Helper class to preserve the original _reexecute bit and _sp and restore
 941 // them back
 942 class PreserveReexecuteState: public StackObj {
 943  protected:
 944   GraphKit*                 _kit;
 945   uint                      _sp;
 946   JVMState::ReexecuteState  _reexecute;
 947 
 948  public:
 949   PreserveReexecuteState(GraphKit* kit);
 950   ~PreserveReexecuteState();
 951 };
 952 
 953 #endif // SHARE_VM_OPTO_GRAPHKIT_HPP