1 /*
   2  * Copyright (c) 2001, 2019, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
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  23  */
  24 
  25 #ifndef SHARE_OPTO_GRAPHKIT_HPP
  26 #define SHARE_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 
  70  private:
  71   int               _sp;        // JVM Expression Stack Pointer; don't modify directly!
  72 
  73  private:
  74   SafePointNode*     map_not_null() const {
  75     assert(_map != NULL, "must call stopped() to test for reset compiler map");
  76     return _map;
  77   }
  78 
  79  public:
  80   GraphKit();                   // empty constructor
  81   GraphKit(JVMState* jvms);     // the JVM state on which to operate
  82 
  83 #ifdef ASSERT
  84   ~GraphKit() {
  85     assert(!has_exceptions(), "user must call transfer_exceptions_into_jvms");
  86   }
  87 #endif
  88 
  89   virtual Parse*          is_Parse()          const { return NULL; }
  90   virtual LibraryCallKit* is_LibraryCallKit() const { return NULL; }
  91 
  92   ciEnv*        env()               const { return _env; }
  93   PhaseGVN&     gvn()               const { return _gvn; }
  94   void*         barrier_set_state() const { return C->barrier_set_state(); }
  95 
  96   void record_for_igvn(Node* n) const { C->record_for_igvn(n); }  // delegate to Compile
  97 
  98   // Handy well-known nodes:
  99   Node*         null()          const { return zerocon(T_OBJECT); }
 100   Node*         top()           const { return C->top(); }
 101   RootNode*     root()          const { return C->root(); }
 102 
 103   // Create or find a constant node
 104   Node* intcon(jint con)        const { return _gvn.intcon(con); }
 105   Node* longcon(jlong con)      const { return _gvn.longcon(con); }
 106   Node* makecon(const Type *t)  const { return _gvn.makecon(t); }
 107   Node* zerocon(BasicType bt)   const { return _gvn.zerocon(bt); }
 108   // (See also macro MakeConX in type.hpp, which uses intcon or longcon.)
 109 
 110   jint  find_int_con(Node* n, jint value_if_unknown) {
 111     return _gvn.find_int_con(n, value_if_unknown);
 112   }
 113   jlong find_long_con(Node* n, jlong value_if_unknown) {
 114     return _gvn.find_long_con(n, value_if_unknown);
 115   }
 116   // (See also macro find_intptr_t_con in type.hpp, which uses one of these.)
 117 
 118   // JVM State accessors:
 119   // Parser mapping from JVM indices into Nodes.
 120   // Low slots are accessed by the StartNode::enum.
 121   // Then come the locals at StartNode::Parms to StartNode::Parms+max_locals();
 122   // Then come JVM stack slots.
 123   // Finally come the monitors, if any.
 124   // See layout accessors in class JVMState.
 125 
 126   SafePointNode*     map()      const { return _map; }
 127   bool               has_exceptions() const { return _exceptions != NULL; }
 128   JVMState*          jvms()     const { return map_not_null()->_jvms; }
 129   int                sp()       const { return _sp; }
 130   int                bci()      const { return _bci; }
 131   Bytecodes::Code    java_bc()  const;
 132   ciMethod*          method()   const { return _method; }
 133 
 134   void set_jvms(JVMState* jvms)       { set_map(jvms->map());
 135                                         assert(jvms == this->jvms(), "sanity");
 136                                         _sp = jvms->sp();
 137                                         _bci = jvms->bci();
 138                                         _method = jvms->has_method() ? jvms->method() : NULL; }
 139   void set_map(SafePointNode* m)      { _map = m; debug_only(verify_map()); }
 140   void set_sp(int sp)                 { assert(sp >= 0, "sp must be non-negative: %d", sp); _sp = sp; }
 141   void clean_stack(int from_sp); // clear garbage beyond from_sp to top
 142 
 143   void inc_sp(int i)                  { set_sp(sp() + i); }
 144   void dec_sp(int i)                  { set_sp(sp() - i); }
 145   void set_bci(int bci)               { _bci = bci; }
 146 
 147   // Make sure jvms has current bci & sp.
 148   JVMState* sync_jvms() const;
 149   JVMState* sync_jvms_for_reexecute();
 150 
 151 #ifdef ASSERT
 152   // Make sure JVMS has an updated copy of bci and sp.
 153   // Also sanity-check method, depth, and monitor depth.
 154   bool jvms_in_sync() const;
 155 
 156   // Make sure the map looks OK.
 157   void verify_map() const;
 158 
 159   // Make sure a proposed exception state looks OK.
 160   static void verify_exception_state(SafePointNode* ex_map);
 161 #endif
 162 
 163   // Clone the existing map state.  (Implements PreserveJVMState.)
 164   SafePointNode* clone_map();
 165 
 166   // Set the map to a clone of the given one.
 167   void set_map_clone(SafePointNode* m);
 168 
 169   // Tell if the compilation is failing.
 170   bool failing() const { return C->failing(); }
 171 
 172   // Set _map to NULL, signalling a stop to further bytecode execution.
 173   // Preserve the map intact for future use, and return it back to the caller.
 174   SafePointNode* stop() { SafePointNode* m = map(); set_map(NULL); return m; }
 175 
 176   // Stop, but first smash the map's inputs to NULL, to mark it dead.
 177   void stop_and_kill_map();
 178 
 179   // Tell if _map is NULL, or control is top.
 180   bool stopped();
 181 
 182   // Tell if this method or any caller method has exception handlers.
 183   bool has_ex_handler();
 184 
 185   // Save an exception without blowing stack contents or other JVM state.
 186   // (The extra pointer is stuck with add_req on the map, beyond the JVMS.)
 187   static void set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop);
 188 
 189   // Recover a saved exception from its map.
 190   static Node* saved_ex_oop(SafePointNode* ex_map);
 191 
 192   // Recover a saved exception from its map, and remove it from the map.
 193   static Node* clear_saved_ex_oop(SafePointNode* ex_map);
 194 
 195 #ifdef ASSERT
 196   // Recover a saved exception from its map, and remove it from the map.
 197   static bool has_saved_ex_oop(SafePointNode* ex_map);
 198 #endif
 199 
 200   // Push an exception in the canonical position for handlers (stack(0)).
 201   void push_ex_oop(Node* ex_oop) {
 202     ensure_stack(1);  // ensure room to push the exception
 203     set_stack(0, ex_oop);
 204     set_sp(1);
 205     clean_stack(1);
 206   }
 207 
 208   // Detach and return an exception state.
 209   SafePointNode* pop_exception_state() {
 210     SafePointNode* ex_map = _exceptions;
 211     if (ex_map != NULL) {
 212       _exceptions = ex_map->next_exception();
 213       ex_map->set_next_exception(NULL);
 214       debug_only(verify_exception_state(ex_map));
 215     }
 216     return ex_map;
 217   }
 218 
 219   // Add an exception, using the given JVM state, without commoning.
 220   void push_exception_state(SafePointNode* ex_map) {
 221     debug_only(verify_exception_state(ex_map));
 222     ex_map->set_next_exception(_exceptions);
 223     _exceptions = ex_map;
 224   }
 225 
 226   // Turn the current JVM state into an exception state, appending the ex_oop.
 227   SafePointNode* make_exception_state(Node* ex_oop);
 228 
 229   // Add an exception, using the given JVM state.
 230   // Combine all exceptions with a common exception type into a single state.
 231   // (This is done via combine_exception_states.)
 232   void add_exception_state(SafePointNode* ex_map);
 233 
 234   // Combine all exceptions of any sort whatever into a single master state.
 235   SafePointNode* combine_and_pop_all_exception_states() {
 236     if (_exceptions == NULL)  return NULL;
 237     SafePointNode* phi_map = pop_exception_state();
 238     SafePointNode* ex_map;
 239     while ((ex_map = pop_exception_state()) != NULL) {
 240       combine_exception_states(ex_map, phi_map);
 241     }
 242     return phi_map;
 243   }
 244 
 245   // Combine the two exception states, building phis as necessary.
 246   // The second argument is updated to include contributions from the first.
 247   void combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map);
 248 
 249   // Reset the map to the given state.  If there are any half-finished phis
 250   // in it (created by combine_exception_states), transform them now.
 251   // Returns the exception oop.  (Caller must call push_ex_oop if required.)
 252   Node* use_exception_state(SafePointNode* ex_map);
 253 
 254   // Collect exceptions from a given JVM state into my exception list.
 255   void add_exception_states_from(JVMState* jvms);
 256 
 257   // Collect all raised exceptions into the current JVM state.
 258   // Clear the current exception list and map, returns the combined states.
 259   JVMState* transfer_exceptions_into_jvms();
 260 
 261   // Helper to throw a built-in exception.
 262   // Range checks take the offending index.
 263   // Cast and array store checks take the offending class.
 264   // Others do not take the optional argument.
 265   // The JVMS must allow the bytecode to be re-executed
 266   // via an uncommon trap.
 267   void builtin_throw(Deoptimization::DeoptReason reason, Node* arg = NULL);
 268 
 269   // Helper to check the JavaThread::_should_post_on_exceptions flag
 270   // and branch to an uncommon_trap if it is true (with the specified reason and must_throw)
 271   void uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
 272                                                   bool must_throw) ;
 273 
 274   // Helper Functions for adding debug information
 275   void kill_dead_locals();
 276 #ifdef ASSERT
 277   bool dead_locals_are_killed();
 278 #endif
 279   // The call may deoptimize.  Supply required JVM state as debug info.
 280   // If must_throw is true, the call is guaranteed not to return normally.
 281   void add_safepoint_edges(SafePointNode* call,
 282                            bool must_throw = false);
 283 
 284   // How many stack inputs does the current BC consume?
 285   // And, how does the stack change after the bytecode?
 286   // Returns false if unknown.
 287   bool compute_stack_effects(int& inputs, int& depth);
 288 
 289   // Add a fixed offset to a pointer
 290   Node* basic_plus_adr(Node* base, Node* ptr, intptr_t offset) {
 291     return basic_plus_adr(base, ptr, MakeConX(offset));
 292   }
 293   Node* basic_plus_adr(Node* base, intptr_t offset) {
 294     return basic_plus_adr(base, base, MakeConX(offset));
 295   }
 296   // Add a variable offset to a pointer
 297   Node* basic_plus_adr(Node* base, Node* offset) {
 298     return basic_plus_adr(base, base, offset);
 299   }
 300   Node* basic_plus_adr(Node* base, Node* ptr, Node* offset);
 301 
 302 
 303   // Some convenient shortcuts for common nodes
 304   Node* IfTrue(IfNode* iff)                   { return _gvn.transform(new IfTrueNode(iff));      }
 305   Node* IfFalse(IfNode* iff)                  { return _gvn.transform(new IfFalseNode(iff));     }
 306 
 307   Node* AddI(Node* l, Node* r)                { return _gvn.transform(new AddINode(l, r));       }
 308   Node* SubI(Node* l, Node* r)                { return _gvn.transform(new SubINode(l, r));       }
 309   Node* MulI(Node* l, Node* r)                { return _gvn.transform(new MulINode(l, r));       }
 310   Node* DivI(Node* ctl, Node* l, Node* r)     { return _gvn.transform(new DivINode(ctl, l, r));  }
 311 
 312   Node* AndI(Node* l, Node* r)                { return _gvn.transform(new AndINode(l, r));       }
 313   Node* OrI(Node* l, Node* r)                 { return _gvn.transform(new OrINode(l, r));        }
 314   Node* XorI(Node* l, Node* r)                { return _gvn.transform(new XorINode(l, r));       }
 315 
 316   Node* MaxI(Node* l, Node* r)                { return _gvn.transform(new MaxINode(l, r));       }
 317   Node* MinI(Node* l, Node* r)                { return _gvn.transform(new MinINode(l, r));       }
 318 
 319   Node* LShiftI(Node* l, Node* r)             { return _gvn.transform(new LShiftINode(l, r));    }
 320   Node* RShiftI(Node* l, Node* r)             { return _gvn.transform(new RShiftINode(l, r));    }
 321   Node* URShiftI(Node* l, Node* r)            { return _gvn.transform(new URShiftINode(l, r));   }
 322 
 323   Node* CmpI(Node* l, Node* r)                { return _gvn.transform(new CmpINode(l, r));       }
 324   Node* CmpL(Node* l, Node* r)                { return _gvn.transform(new CmpLNode(l, r));       }
 325   Node* CmpP(Node* l, Node* r)                { return _gvn.transform(new CmpPNode(l, r));       }
 326   Node* Bool(Node* cmp, BoolTest::mask relop) { return _gvn.transform(new BoolNode(cmp, relop)); }
 327 
 328   Node* AddP(Node* b, Node* a, Node* o)       { return _gvn.transform(new AddPNode(b, a, o));    }
 329 
 330   // Convert between int and long, and size_t.
 331   // (See macros ConvI2X, etc., in type.hpp for ConvI2X, etc.)
 332   Node* ConvI2L(Node* offset);
 333   Node* ConvI2UL(Node* offset);
 334   Node* ConvL2I(Node* offset);
 335   // Find out the klass of an object.
 336   Node* load_object_klass(Node* object);
 337   // Find out the length of an array.
 338   Node* load_array_length(Node* array);
 339 
 340 
 341   // Helper function to do a NULL pointer check or ZERO check based on type.
 342   // Throw an exception if a given value is null.
 343   // Return the value cast to not-null.
 344   // Be clever about equivalent dominating null checks.
 345   Node* null_check_common(Node* value, BasicType type,
 346                           bool assert_null = false,
 347                           Node* *null_control = NULL,
 348                           bool speculative = false);
 349   Node* null_check(Node* value, BasicType type = T_OBJECT) {
 350     return null_check_common(value, type, false, NULL, !_gvn.type(value)->speculative_maybe_null());
 351   }
 352   Node* null_check_receiver() {
 353     assert(argument(0)->bottom_type()->isa_ptr(), "must be");
 354     return null_check(argument(0));
 355   }
 356   Node* zero_check_int(Node* value) {
 357     assert(value->bottom_type()->basic_type() == T_INT,
 358            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
 359     return null_check_common(value, T_INT);
 360   }
 361   Node* zero_check_long(Node* value) {
 362     assert(value->bottom_type()->basic_type() == T_LONG,
 363            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
 364     return null_check_common(value, T_LONG);
 365   }
 366   // Throw an uncommon trap if a given value is __not__ null.
 367   // Return the value cast to null, and be clever about dominating checks.
 368   Node* null_assert(Node* value, BasicType type = T_OBJECT) {
 369     return null_check_common(value, type, true, NULL, _gvn.type(value)->speculative_always_null());
 370   }
 371 
 372   // Check if value is null and abort if it is
 373   Node* must_be_not_null(Node* value, bool do_replace_in_map);
 374 
 375   // Null check oop.  Return null-path control into (*null_control).
 376   // Return a cast-not-null node which depends on the not-null control.
 377   // If never_see_null, use an uncommon trap (*null_control sees a top).
 378   // The cast is not valid along the null path; keep a copy of the original.
 379   // If safe_for_replace, then we can replace the value with the cast
 380   // in the parsing map (the cast is guaranteed to dominate the map)
 381   Node* null_check_oop(Node* value, Node* *null_control,
 382                        bool never_see_null = false,
 383                        bool safe_for_replace = false,
 384                        bool speculative = false);
 385 
 386   // Check the null_seen bit.
 387   bool seems_never_null(Node* obj, ciProfileData* data, bool& speculating);
 388 
 389   // Check for unique class for receiver at call
 390   ciKlass* profile_has_unique_klass() {
 391     ciCallProfile profile = method()->call_profile_at_bci(bci());
 392     if (profile.count() >= 0 &&         // no cast failures here
 393         profile.has_receiver(0) &&
 394         profile.morphism() == 1) {
 395       return profile.receiver(0);
 396     }
 397     return NULL;
 398   }
 399 
 400   // record type from profiling with the type system
 401   Node* record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind);
 402   void record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc);
 403   void record_profiled_parameters_for_speculation();
 404   void record_profiled_return_for_speculation();
 405   Node* record_profiled_receiver_for_speculation(Node* n);
 406 
 407   // Use the type profile to narrow an object type.
 408   Node* maybe_cast_profiled_receiver(Node* not_null_obj,
 409                                      ciKlass* require_klass,
 410                                      ciKlass* spec,
 411                                      bool safe_for_replace);
 412 
 413   // Cast obj to type and emit guard unless we had too many traps here already
 414   Node* maybe_cast_profiled_obj(Node* obj,
 415                                 ciKlass* type,
 416                                 bool not_null = false);
 417 
 418   // Cast obj to not-null on this path
 419   Node* cast_not_null(Node* obj, bool do_replace_in_map = true);
 420   // Replace all occurrences of one node by another.
 421   void replace_in_map(Node* old, Node* neww);
 422 
 423   void  push(Node* n)     { map_not_null();        _map->set_stack(_map->_jvms,   _sp++        , n); }
 424   Node* pop()             { map_not_null(); return _map->stack(    _map->_jvms, --_sp             ); }
 425   Node* peek(int off = 0) { map_not_null(); return _map->stack(    _map->_jvms,   _sp - off - 1   ); }
 426 
 427   void push_pair(Node* ldval) {
 428     push(ldval);
 429     push(top());  // the halfword is merely a placeholder
 430   }
 431   void push_pair_local(int i) {
 432     // longs are stored in locals in "push" order
 433     push(  local(i+0) );  // the real value
 434     assert(local(i+1) == top(), "");
 435     push(top());  // halfword placeholder
 436   }
 437   Node* pop_pair() {
 438     // the second half is pushed last & popped first; it contains exactly nothing
 439     Node* halfword = pop();
 440     assert(halfword == top(), "");
 441     // the long bits are pushed first & popped last:
 442     return pop();
 443   }
 444   void set_pair_local(int i, Node* lval) {
 445     // longs are stored in locals as a value/half pair (like doubles)
 446     set_local(i+0, lval);
 447     set_local(i+1, top());
 448   }
 449 
 450   // Push the node, which may be zero, one, or two words.
 451   void push_node(BasicType n_type, Node* n) {
 452     int n_size = type2size[n_type];
 453     if      (n_size == 1)  push(      n );  // T_INT, ...
 454     else if (n_size == 2)  push_pair( n );  // T_DOUBLE, T_LONG
 455     else                   { assert(n_size == 0, "must be T_VOID"); }
 456   }
 457 
 458   Node* pop_node(BasicType n_type) {
 459     int n_size = type2size[n_type];
 460     if      (n_size == 1)  return pop();
 461     else if (n_size == 2)  return pop_pair();
 462     else                   return NULL;
 463   }
 464 
 465   Node* control()               const { return map_not_null()->control(); }
 466   Node* i_o()                   const { return map_not_null()->i_o(); }
 467   Node* returnadr()             const { return map_not_null()->returnadr(); }
 468   Node* frameptr()              const { return map_not_null()->frameptr(); }
 469   Node* local(uint idx)         const { map_not_null(); return _map->local(      _map->_jvms, idx); }
 470   Node* stack(uint idx)         const { map_not_null(); return _map->stack(      _map->_jvms, idx); }
 471   Node* argument(uint idx)      const { map_not_null(); return _map->argument(   _map->_jvms, idx); }
 472   Node* monitor_box(uint idx)   const { map_not_null(); return _map->monitor_box(_map->_jvms, idx); }
 473   Node* monitor_obj(uint idx)   const { map_not_null(); return _map->monitor_obj(_map->_jvms, idx); }
 474 
 475   void set_control  (Node* c)         { map_not_null()->set_control(c); }
 476   void set_i_o      (Node* c)         { map_not_null()->set_i_o(c); }
 477   void set_local(uint idx, Node* c)   { map_not_null(); _map->set_local(   _map->_jvms, idx, c); }
 478   void set_stack(uint idx, Node* c)   { map_not_null(); _map->set_stack(   _map->_jvms, idx, c); }
 479   void set_argument(uint idx, Node* c){ map_not_null(); _map->set_argument(_map->_jvms, idx, c); }
 480   void ensure_stack(uint stk_size)    { map_not_null(); _map->ensure_stack(_map->_jvms, stk_size); }
 481 
 482   // Access unaliased memory
 483   Node* memory(uint alias_idx);
 484   Node* memory(const TypePtr *tp) { return memory(C->get_alias_index(tp)); }
 485   Node* memory(Node* adr) { return memory(_gvn.type(adr)->is_ptr()); }
 486 
 487   // Access immutable memory
 488   Node* immutable_memory() { return C->immutable_memory(); }
 489 
 490   // Set unaliased memory
 491   void set_memory(Node* c, uint alias_idx) { merged_memory()->set_memory_at(alias_idx, c); }
 492   void set_memory(Node* c, const TypePtr *tp) { set_memory(c,C->get_alias_index(tp)); }
 493   void set_memory(Node* c, Node* adr) { set_memory(c,_gvn.type(adr)->is_ptr()); }
 494 
 495   // Get the entire memory state (probably a MergeMemNode), and reset it
 496   // (The resetting prevents somebody from using the dangling Node pointer.)
 497   Node* reset_memory();
 498 
 499   // Get the entire memory state, asserted to be a MergeMemNode.
 500   MergeMemNode* merged_memory() {
 501     Node* mem = map_not_null()->memory();
 502     assert(mem->is_MergeMem(), "parse memory is always pre-split");
 503     return mem->as_MergeMem();
 504   }
 505 
 506   // Set the entire memory state; produce a new MergeMemNode.
 507   void set_all_memory(Node* newmem);
 508 
 509   // Create a memory projection from the call, then set_all_memory.
 510   void set_all_memory_call(Node* call, bool separate_io_proj = false);
 511 
 512   // Create a LoadNode, reading from the parser's memory state.
 513   // (Note:  require_atomic_access is useful only with T_LONG.)
 514   //
 515   // We choose the unordered semantics by default because we have
 516   // adapted the `do_put_xxx' and `do_get_xxx' procedures for the case
 517   // of volatile fields.
 518   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
 519                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
 520                   bool require_atomic_access = false, bool unaligned = false,
 521                   bool mismatched = false, bool unsafe = false) {
 522     // This version computes alias_index from bottom_type
 523     return make_load(ctl, adr, t, bt, adr->bottom_type()->is_ptr(),
 524                      mo, control_dependency, require_atomic_access,
 525                      unaligned, mismatched, unsafe);
 526   }
 527   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, const TypePtr* adr_type,
 528                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
 529                   bool require_atomic_access = false, bool unaligned = false,
 530                   bool mismatched = false, bool unsafe = false) {
 531     // This version computes alias_index from an address type
 532     assert(adr_type != NULL, "use other make_load factory");
 533     return make_load(ctl, adr, t, bt, C->get_alias_index(adr_type),
 534                      mo, control_dependency, require_atomic_access,
 535                      unaligned, mismatched, unsafe);
 536   }
 537   // This is the base version which is given an alias index.
 538   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, int adr_idx,
 539                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
 540                   bool require_atomic_access = false, bool unaligned = false,
 541                   bool mismatched = false, bool unsafe = false);
 542 
 543   // Create & transform a StoreNode and store the effect into the
 544   // parser's memory state.
 545   //
 546   // We must ensure that stores of object references will be visible
 547   // only after the object's initialization. So the clients of this
 548   // procedure must indicate that the store requires `release'
 549   // semantics, if the stored value is an object reference that might
 550   // point to a new object and may become externally visible.
 551   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
 552                         const TypePtr* adr_type,
 553                         MemNode::MemOrd mo,
 554                         bool require_atomic_access = false,
 555                         bool unaligned = false,
 556                         bool mismatched = false,
 557                         bool unsafe = false) {
 558     // This version computes alias_index from an address type
 559     assert(adr_type != NULL, "use other store_to_memory factory");
 560     return store_to_memory(ctl, adr, val, bt,
 561                            C->get_alias_index(adr_type),
 562                            mo, require_atomic_access,
 563                            unaligned, mismatched);
 564   }
 565   // This is the base version which is given alias index
 566   // Return the new StoreXNode
 567   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
 568                         int adr_idx,
 569                         MemNode::MemOrd,
 570                         bool require_atomic_access = false,
 571                         bool unaligned = false,
 572                         bool mismatched = false,
 573                         bool unsafe = false);
 574 
 575   // Perform decorated accesses
 576 
 577   Node* access_store_at(Node* obj,   // containing obj
 578                         Node* adr,   // actual adress to store val at
 579                         const TypePtr* adr_type,
 580                         Node* val,
 581                         const Type* val_type,
 582                         BasicType bt,
 583                         DecoratorSet decorators);
 584 
 585   Node* access_load_at(Node* obj,   // containing obj
 586                        Node* adr,   // actual adress to load val at
 587                        const TypePtr* adr_type,
 588                        const Type* val_type,
 589                        BasicType bt,
 590                        DecoratorSet decorators);
 591 
 592   Node* access_load(Node* adr,   // actual adress to load val at
 593                     const Type* val_type,
 594                     BasicType bt,
 595                     DecoratorSet decorators);
 596 
 597   Node* access_atomic_cmpxchg_val_at(Node* obj,
 598                                      Node* adr,
 599                                      const TypePtr* adr_type,
 600                                      int alias_idx,
 601                                      Node* expected_val,
 602                                      Node* new_val,
 603                                      const Type* value_type,
 604                                      BasicType bt,
 605                                      DecoratorSet decorators);
 606 
 607   Node* access_atomic_cmpxchg_bool_at(Node* obj,
 608                                       Node* adr,
 609                                       const TypePtr* adr_type,
 610                                       int alias_idx,
 611                                       Node* expected_val,
 612                                       Node* new_val,
 613                                       const Type* value_type,
 614                                       BasicType bt,
 615                                       DecoratorSet decorators);
 616 
 617   Node* access_atomic_xchg_at(Node* obj,
 618                               Node* adr,
 619                               const TypePtr* adr_type,
 620                               int alias_idx,
 621                               Node* new_val,
 622                               const Type* value_type,
 623                               BasicType bt,
 624                               DecoratorSet decorators);
 625 
 626   Node* access_atomic_add_at(Node* obj,
 627                              Node* adr,
 628                              const TypePtr* adr_type,
 629                              int alias_idx,
 630                              Node* new_val,
 631                              const Type* value_type,
 632                              BasicType bt,
 633                              DecoratorSet decorators);
 634 
 635   void access_clone(Node* src, Node* dst, Node* size, bool is_array);
 636 
 637   Node* access_resolve(Node* n, DecoratorSet decorators);
 638 
 639   // Return addressing for an array element.
 640   Node* array_element_address(Node* ary, Node* idx, BasicType elembt,
 641                               // Optional constraint on the array size:
 642                               const TypeInt* sizetype = NULL,
 643                               // Optional control dependency (for example, on range check)
 644                               Node* ctrl = NULL);
 645 
 646   // Return a load of array element at idx.
 647   Node* load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype);
 648 
 649   //---------------- Dtrace support --------------------
 650   void make_dtrace_method_entry_exit(ciMethod* method, bool is_entry);
 651   void make_dtrace_method_entry(ciMethod* method) {
 652     make_dtrace_method_entry_exit(method, true);
 653   }
 654   void make_dtrace_method_exit(ciMethod* method) {
 655     make_dtrace_method_entry_exit(method, false);
 656   }
 657 
 658   //--------------- stub generation -------------------
 659  public:
 660   void gen_stub(address C_function,
 661                 const char *name,
 662                 int is_fancy_jump,
 663                 bool pass_tls,
 664                 bool return_pc);
 665 
 666   //---------- help for generating calls --------------
 667 
 668   // Do a null check on the receiver as it would happen before the call to
 669   // callee (with all arguments still on the stack).
 670   Node* null_check_receiver_before_call(ciMethod* callee) {
 671     assert(!callee->is_static(), "must be a virtual method");
 672     // Callsite signature can be different from actual method being called (i.e _linkTo* sites).
 673     // Use callsite signature always.
 674     ciMethod* declared_method = method()->get_method_at_bci(bci());
 675     const int nargs = declared_method->arg_size();
 676     inc_sp(nargs);
 677     Node* n = null_check_receiver();
 678     dec_sp(nargs);
 679     return n;
 680   }
 681 
 682   // Fill in argument edges for the call from argument(0), argument(1), ...
 683   // (The next step is to call set_edges_for_java_call.)
 684   void  set_arguments_for_java_call(CallJavaNode* call);
 685 
 686   // Fill in non-argument edges for the call.
 687   // Transform the call, and update the basics: control, i_o, memory.
 688   // (The next step is usually to call set_results_for_java_call.)
 689   void set_edges_for_java_call(CallJavaNode* call,
 690                                bool must_throw = false, bool separate_io_proj = false);
 691 
 692   // Finish up a java call that was started by set_edges_for_java_call.
 693   // Call add_exception on any throw arising from the call.
 694   // Return the call result (transformed).
 695   Node* set_results_for_java_call(CallJavaNode* call, bool separate_io_proj = false, bool deoptimize = false);
 696 
 697   // Similar to set_edges_for_java_call, but simplified for runtime calls.
 698   void  set_predefined_output_for_runtime_call(Node* call) {
 699     set_predefined_output_for_runtime_call(call, NULL, NULL);
 700   }
 701   void  set_predefined_output_for_runtime_call(Node* call,
 702                                                Node* keep_mem,
 703                                                const TypePtr* hook_mem);
 704   Node* set_predefined_input_for_runtime_call(SafePointNode* call, Node* narrow_mem = NULL);
 705 
 706   // Replace the call with the current state of the kit.  Requires
 707   // that the call was generated with separate io_projs so that
 708   // exceptional control flow can be handled properly.
 709   void replace_call(CallNode* call, Node* result, bool do_replaced_nodes = false);
 710 
 711   // helper functions for statistics
 712   void increment_counter(address counter_addr);   // increment a debug counter
 713   void increment_counter(Node*   counter_addr);   // increment a debug counter
 714 
 715   // Bail out to the interpreter right now
 716   // The optional klass is the one causing the trap.
 717   // The optional reason is debug information written to the compile log.
 718   // Optional must_throw is the same as with add_safepoint_edges.
 719   void uncommon_trap(int trap_request,
 720                      ciKlass* klass = NULL, const char* reason_string = NULL,
 721                      bool must_throw = false, bool keep_exact_action = false);
 722 
 723   // Shorthand, to avoid saying "Deoptimization::" so many times.
 724   void uncommon_trap(Deoptimization::DeoptReason reason,
 725                      Deoptimization::DeoptAction action,
 726                      ciKlass* klass = NULL, const char* reason_string = NULL,
 727                      bool must_throw = false, bool keep_exact_action = false) {
 728     uncommon_trap(Deoptimization::make_trap_request(reason, action),
 729                   klass, reason_string, must_throw, keep_exact_action);
 730   }
 731 
 732   // Bail out to the interpreter and keep exact action (avoid switching to Action_none).
 733   void uncommon_trap_exact(Deoptimization::DeoptReason reason,
 734                            Deoptimization::DeoptAction action,
 735                            ciKlass* klass = NULL, const char* reason_string = NULL,
 736                            bool must_throw = false) {
 737     uncommon_trap(Deoptimization::make_trap_request(reason, action),
 738                   klass, reason_string, must_throw, /*keep_exact_action=*/true);
 739   }
 740 
 741   // SP when bytecode needs to be reexecuted.
 742   virtual int reexecute_sp() { return sp(); }
 743 
 744   // Report if there were too many traps at the current method and bci.
 745   // Report if a trap was recorded, and/or PerMethodTrapLimit was exceeded.
 746   // If there is no MDO at all, report no trap unless told to assume it.
 747   bool too_many_traps(Deoptimization::DeoptReason reason) {
 748     return C->too_many_traps(method(), bci(), reason);
 749   }
 750 
 751   // Report if there were too many recompiles at the current method and bci.
 752   bool too_many_recompiles(Deoptimization::DeoptReason reason) {
 753     return C->too_many_recompiles(method(), bci(), reason);
 754   }
 755 
 756   bool too_many_traps_or_recompiles(Deoptimization::DeoptReason reason) {
 757       return C->too_many_traps_or_recompiles(method(), bci(), reason);
 758   }
 759 
 760   // Returns the object (if any) which was created the moment before.
 761   Node* just_allocated_object(Node* current_control);
 762 
 763   // Sync Ideal and Graph kits.
 764   void sync_kit(IdealKit& ideal);
 765   void final_sync(IdealKit& ideal);
 766 
 767   public:
 768   // Helper function to round double arguments before a call
 769   void round_double_arguments(ciMethod* dest_method);
 770   void round_double_result(ciMethod* dest_method);
 771 
 772   // rounding for strict float precision conformance
 773   Node* precision_rounding(Node* n);
 774 
 775   // rounding for strict double precision conformance
 776   Node* dprecision_rounding(Node* n);
 777 
 778   // rounding for non-strict double stores
 779   Node* dstore_rounding(Node* n);
 780 
 781   // Helper functions for fast/slow path codes
 782   Node* opt_iff(Node* region, Node* iff);
 783   Node* make_runtime_call(int flags,
 784                           const TypeFunc* call_type, address call_addr,
 785                           const char* call_name,
 786                           const TypePtr* adr_type, // NULL if no memory effects
 787                           Node* parm0 = NULL, Node* parm1 = NULL,
 788                           Node* parm2 = NULL, Node* parm3 = NULL,
 789                           Node* parm4 = NULL, Node* parm5 = NULL,
 790                           Node* parm6 = NULL, Node* parm7 = NULL);
 791   enum {  // flag values for make_runtime_call
 792     RC_NO_FP = 1,               // CallLeafNoFPNode
 793     RC_NO_IO = 2,               // do not hook IO edges
 794     RC_NO_LEAF = 4,             // CallStaticJavaNode
 795     RC_MUST_THROW = 8,          // flag passed to add_safepoint_edges
 796     RC_NARROW_MEM = 16,         // input memory is same as output
 797     RC_UNCOMMON = 32,           // freq. expected to be like uncommon trap
 798     RC_LEAF = 0                 // null value:  no flags set
 799   };
 800 
 801   // merge in all memory slices from new_mem, along the given path
 802   void merge_memory(Node* new_mem, Node* region, int new_path);
 803   void make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize = false);
 804 
 805   // Helper functions to build synchronizations
 806   int next_monitor();
 807   Node* insert_mem_bar(int opcode, Node* precedent = NULL);
 808   Node* insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent = NULL);
 809   void insert_store_load_for_barrier();
 810   // Optional 'precedent' is appended as an extra edge, to force ordering.
 811   FastLockNode* shared_lock(Node* obj);
 812   void shared_unlock(Node* box, Node* obj);
 813 
 814   // helper functions for the fast path/slow path idioms
 815   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);
 816 
 817   // Generate an instance-of idiom.  Used by both the instance-of bytecode
 818   // and the reflective instance-of call.
 819   Node* gen_instanceof(Node *subobj, Node* superkls, bool safe_for_replace = false);
 820 
 821   // Generate a check-cast idiom.  Used by both the check-cast bytecode
 822   // and the array-store bytecode
 823   Node* gen_checkcast( Node *subobj, Node* superkls,
 824                        Node* *failure_control = NULL );
 825 
 826   Node* gen_subtype_check(Node* subklass, Node* superklass) {
 827     MergeMemNode* mem = merged_memory();
 828     Node* ctrl = control();
 829     Node* n = Phase::gen_subtype_check(subklass, superklass, &ctrl, mem, &_gvn);
 830     set_control(ctrl);
 831     return n;
 832   }
 833 
 834   // Exact type check used for predicted calls and casts.
 835   // Rewrites (*casted_receiver) to be casted to the stronger type.
 836   // (Caller is responsible for doing replace_in_map.)
 837   Node* type_check_receiver(Node* receiver, ciKlass* klass, float prob,
 838                             Node* *casted_receiver);
 839 
 840   // Inexact type check used for predicted calls.
 841   Node* subtype_check_receiver(Node* receiver, ciKlass* klass,
 842                                Node** casted_receiver);
 843 
 844   // implementation of object creation
 845   Node* set_output_for_allocation(AllocateNode* alloc,
 846                                   const TypeOopPtr* oop_type,
 847                                   bool deoptimize_on_exception=false);
 848   Node* get_layout_helper(Node* klass_node, jint& constant_value);
 849   Node* new_instance(Node* klass_node,
 850                      Node* slow_test = NULL,
 851                      Node* *return_size_val = NULL,
 852                      bool deoptimize_on_exception = false);
 853   Node* new_array(Node* klass_node, Node* count_val, int nargs,
 854                   Node* *return_size_val = NULL,
 855                   bool deoptimize_on_exception = false);
 856 
 857   // java.lang.String helpers
 858   Node* load_String_length(Node* str, bool set_ctrl);
 859   Node* load_String_value(Node* str, bool set_ctrl);
 860   Node* load_String_coder(Node* str, bool set_ctrl);
 861   void store_String_value(Node* str, Node* value);
 862   void store_String_coder(Node* str, Node* value);
 863   Node* capture_memory(const TypePtr* src_type, const TypePtr* dst_type);
 864   Node* compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count);
 865   void inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count);
 866   void inflate_string_slow(Node* src, Node* dst, Node* start, Node* count);
 867 
 868   // Handy for making control flow
 869   IfNode* create_and_map_if(Node* ctrl, Node* tst, float prob, float cnt) {
 870     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
 871     _gvn.set_type(iff, iff->Value(&_gvn)); // Value may be known at parse-time
 872     // Place 'if' on worklist if it will be in graph
 873     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
 874     return iff;
 875   }
 876 
 877   IfNode* create_and_xform_if(Node* ctrl, Node* tst, float prob, float cnt) {
 878     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
 879     _gvn.transform(iff);                           // Value may be known at parse-time
 880     // Place 'if' on worklist if it will be in graph
 881     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
 882     return iff;
 883   }
 884 
 885   // Insert a loop predicate into the graph
 886   void add_predicate(int nargs = 0);
 887   void add_predicate_impl(Deoptimization::DeoptReason reason, int nargs);
 888 
 889   Node* make_constant_from_field(ciField* field, Node* obj);
 890 };
 891 
 892 // Helper class to support building of control flow branches. Upon
 893 // creation the map and sp at bci are cloned and restored upon de-
 894 // struction. Typical use:
 895 //
 896 // { PreserveJVMState pjvms(this);
 897 //   // code of new branch
 898 // }
 899 // // here the JVM state at bci is established
 900 
 901 class PreserveJVMState: public StackObj {
 902  protected:
 903   GraphKit*      _kit;
 904 #ifdef ASSERT
 905   int            _block;  // PO of current block, if a Parse
 906   int            _bci;
 907 #endif
 908   SafePointNode* _map;
 909   uint           _sp;
 910 
 911  public:
 912   PreserveJVMState(GraphKit* kit, bool clone_map = true);
 913   ~PreserveJVMState();
 914 };
 915 
 916 // Helper class to build cutouts of the form if (p) ; else {x...}.
 917 // The code {x...} must not fall through.
 918 // The kit's main flow of control is set to the "then" continuation of if(p).
 919 class BuildCutout: public PreserveJVMState {
 920  public:
 921   BuildCutout(GraphKit* kit, Node* p, float prob, float cnt = COUNT_UNKNOWN);
 922   ~BuildCutout();
 923 };
 924 
 925 // Helper class to preserve the original _reexecute bit and _sp and restore
 926 // them back
 927 class PreserveReexecuteState: public StackObj {
 928  protected:
 929   GraphKit*                 _kit;
 930   uint                      _sp;
 931   JVMState::ReexecuteState  _reexecute;
 932 
 933  public:
 934   PreserveReexecuteState(GraphKit* kit);
 935   ~PreserveReexecuteState();
 936 };
 937 
 938 #endif // SHARE_OPTO_GRAPHKIT_HPP