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.
  22  *
  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 "opto/valuetypenode.hpp"
  41 #include "runtime/deoptimization.hpp"
  42 
  43 class BarrierSetC2;
  44 class FastLockNode;
  45 class FastUnlockNode;
  46 class IdealKit;
  47 class LibraryCallKit;
  48 class Parse;
  49 class RootNode;
  50 
  51 //-----------------------------------------------------------------------------
  52 //----------------------------GraphKit-----------------------------------------
  53 // Toolkit for building the common sorts of subgraphs.
  54 // Does not know about bytecode parsing or type-flow results.
  55 // It is able to create graphs implementing the semantics of most
  56 // or all bytecodes, so that it can expand intrinsics and calls.
  57 // It may depend on JVMState structure, but it must not depend
  58 // on specific bytecode streams.
  59 class GraphKit : public Phase {
  60   friend class PreserveJVMState;
  61 
  62  protected:
  63   ciEnv*            _env;       // Compilation environment
  64   PhaseGVN         &_gvn;       // Some optimizations while parsing
  65   SafePointNode*    _map;       // Parser map from JVM to Nodes
  66   SafePointNode*    _exceptions;// Parser map(s) for exception state(s)
  67   int               _bci;       // JVM Bytecode Pointer
  68   ciMethod*         _method;    // JVM Current Method
  69   BarrierSetC2*     _barrier_set;
  70 #ifdef ASSERT
  71   uint              _worklist_size;
  72 #endif
  73 
  74  private:
  75   int               _sp;        // JVM Expression Stack Pointer; don't modify directly!
  76 
  77  private:
  78   SafePointNode*     map_not_null() const {
  79     assert(_map != NULL, "must call stopped() to test for reset compiler map");
  80     return _map;
  81   }
  82 
  83  public:
  84   GraphKit();                   // empty constructor
  85   GraphKit(JVMState* jvms, PhaseGVN* gvn = NULL);     // the JVM state on which to operate
  86 
  87 #ifdef ASSERT
  88   ~GraphKit() {
  89     assert(!has_exceptions(), "user must call transfer_exceptions_into_jvms");
  90     // During incremental inlining, the Node_Array of the C->for_igvn() worklist and the IGVN
  91     // worklist are shared but the _in_worklist VectorSet is not. To avoid inconsistencies,
  92     // we should not add nodes to the _for_igvn worklist when using IGVN for the GraphKit.
  93     assert((_gvn.is_IterGVN() == NULL) || (_gvn.C->for_igvn()->size() == _worklist_size),
  94            "GraphKit should not modify _for_igvn worklist after parsing");
  95   }
  96 #endif
  97 
  98   virtual Parse*          is_Parse()          const { return NULL; }
  99   virtual LibraryCallKit* is_LibraryCallKit() const { return NULL; }
 100 
 101   ciEnv*        env()               const { return _env; }
 102   PhaseGVN&     gvn()               const { return _gvn; }
 103   void*         barrier_set_state() const { return C->barrier_set_state(); }
 104 
 105   void record_for_igvn(Node* n) const { _gvn.record_for_igvn(n); }
 106 
 107   // Handy well-known nodes:
 108   Node*         null()          const { return zerocon(T_OBJECT); }
 109   Node*         top()           const { return C->top(); }
 110   RootNode*     root()          const { return C->root(); }
 111 
 112   // Create or find a constant node
 113   Node* intcon(jint con)        const { return _gvn.intcon(con); }
 114   Node* longcon(jlong con)      const { return _gvn.longcon(con); }
 115   Node* makecon(const Type *t)  const { return _gvn.makecon(t); }
 116   Node* zerocon(BasicType bt)   const { return _gvn.zerocon(bt); }
 117   // (See also macro MakeConX in type.hpp, which uses intcon or longcon.)
 118 
 119   jint  find_int_con(Node* n, jint value_if_unknown) {
 120     return _gvn.find_int_con(n, value_if_unknown);
 121   }
 122   jlong find_long_con(Node* n, jlong value_if_unknown) {
 123     return _gvn.find_long_con(n, value_if_unknown);
 124   }
 125   // (See also macro find_intptr_t_con in type.hpp, which uses one of these.)
 126 
 127   // JVM State accessors:
 128   // Parser mapping from JVM indices into Nodes.
 129   // Low slots are accessed by the StartNode::enum.
 130   // Then come the locals at StartNode::Parms to StartNode::Parms+max_locals();
 131   // Then come JVM stack slots.
 132   // Finally come the monitors, if any.
 133   // See layout accessors in class JVMState.
 134 
 135   SafePointNode*     map()      const { return _map; }
 136   bool               has_exceptions() const { return _exceptions != NULL; }
 137   JVMState*          jvms()     const { return map_not_null()->_jvms; }
 138   int                sp()       const { return _sp; }
 139   int                bci()      const { return _bci; }
 140   Bytecodes::Code    java_bc()  const;
 141   ciMethod*          method()   const { return _method; }
 142 
 143   void set_jvms(JVMState* jvms)       { set_map(jvms->map());
 144                                         assert(jvms == this->jvms(), "sanity");
 145                                         _sp = jvms->sp();
 146                                         _bci = jvms->bci();
 147                                         _method = jvms->has_method() ? jvms->method() : NULL; }
 148   void set_map(SafePointNode* m)      { _map = m; debug_only(verify_map()); }
 149   void set_sp(int sp)                 { assert(sp >= 0, "sp must be non-negative: %d", sp); _sp = sp; }
 150   void clean_stack(int from_sp); // clear garbage beyond from_sp to top
 151 
 152   void inc_sp(int i)                  { set_sp(sp() + i); }
 153   void dec_sp(int i)                  { set_sp(sp() - i); }
 154   void set_bci(int bci)               { _bci = bci; }
 155 
 156   // Make sure jvms has current bci & sp.
 157   JVMState* sync_jvms() const;
 158   JVMState* sync_jvms_for_reexecute();
 159 
 160 #ifdef ASSERT
 161   // Make sure JVMS has an updated copy of bci and sp.
 162   // Also sanity-check method, depth, and monitor depth.
 163   bool jvms_in_sync() const;
 164 
 165   // Make sure the map looks OK.
 166   void verify_map() const;
 167 
 168   // Make sure a proposed exception state looks OK.
 169   static void verify_exception_state(SafePointNode* ex_map);
 170 #endif
 171 
 172   // Clone the existing map state.  (Implements PreserveJVMState.)
 173   SafePointNode* clone_map();
 174 
 175   // Set the map to a clone of the given one.
 176   void set_map_clone(SafePointNode* m);
 177 
 178   // Tell if the compilation is failing.
 179   bool failing() const { return C->failing(); }
 180 
 181   // Set _map to NULL, signalling a stop to further bytecode execution.
 182   // Preserve the map intact for future use, and return it back to the caller.
 183   SafePointNode* stop() { SafePointNode* m = map(); set_map(NULL); return m; }
 184 
 185   // Stop, but first smash the map's inputs to NULL, to mark it dead.
 186   void stop_and_kill_map();
 187 
 188   // Tell if _map is NULL, or control is top.
 189   bool stopped();
 190 
 191   // Tell if this method or any caller method has exception handlers.
 192   bool has_ex_handler();
 193 
 194   // Save an exception without blowing stack contents or other JVM state.
 195   // (The extra pointer is stuck with add_req on the map, beyond the JVMS.)
 196   static void set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop);
 197 
 198   // Recover a saved exception from its map.
 199   static Node* saved_ex_oop(SafePointNode* ex_map);
 200 
 201   // Recover a saved exception from its map, and remove it from the map.
 202   static Node* clear_saved_ex_oop(SafePointNode* ex_map);
 203 
 204 #ifdef ASSERT
 205   // Recover a saved exception from its map, and remove it from the map.
 206   static bool has_saved_ex_oop(SafePointNode* ex_map);
 207 #endif
 208 
 209   // Push an exception in the canonical position for handlers (stack(0)).
 210   void push_ex_oop(Node* ex_oop) {
 211     ensure_stack(1);  // ensure room to push the exception
 212     set_stack(0, ex_oop);
 213     set_sp(1);
 214     clean_stack(1);
 215   }
 216 
 217   // Detach and return an exception state.
 218   SafePointNode* pop_exception_state() {
 219     SafePointNode* ex_map = _exceptions;
 220     if (ex_map != NULL) {
 221       _exceptions = ex_map->next_exception();
 222       ex_map->set_next_exception(NULL);
 223       debug_only(verify_exception_state(ex_map));
 224     }
 225     return ex_map;
 226   }
 227 
 228   // Add an exception, using the given JVM state, without commoning.
 229   void push_exception_state(SafePointNode* ex_map) {
 230     debug_only(verify_exception_state(ex_map));
 231     ex_map->set_next_exception(_exceptions);
 232     _exceptions = ex_map;
 233   }
 234 
 235   // Turn the current JVM state into an exception state, appending the ex_oop.
 236   SafePointNode* make_exception_state(Node* ex_oop);
 237 
 238   // Add an exception, using the given JVM state.
 239   // Combine all exceptions with a common exception type into a single state.
 240   // (This is done via combine_exception_states.)
 241   void add_exception_state(SafePointNode* ex_map);
 242 
 243   // Combine all exceptions of any sort whatever into a single master state.
 244   SafePointNode* combine_and_pop_all_exception_states() {
 245     if (_exceptions == NULL)  return NULL;
 246     SafePointNode* phi_map = pop_exception_state();
 247     SafePointNode* ex_map;
 248     while ((ex_map = pop_exception_state()) != NULL) {
 249       combine_exception_states(ex_map, phi_map);
 250     }
 251     return phi_map;
 252   }
 253 
 254   // Combine the two exception states, building phis as necessary.
 255   // The second argument is updated to include contributions from the first.
 256   void combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map);
 257 
 258   // Reset the map to the given state.  If there are any half-finished phis
 259   // in it (created by combine_exception_states), transform them now.
 260   // Returns the exception oop.  (Caller must call push_ex_oop if required.)
 261   Node* use_exception_state(SafePointNode* ex_map);
 262 
 263   // Collect exceptions from a given JVM state into my exception list.
 264   void add_exception_states_from(JVMState* jvms);
 265 
 266   // Collect all raised exceptions into the current JVM state.
 267   // Clear the current exception list and map, returns the combined states.
 268   JVMState* transfer_exceptions_into_jvms();
 269 
 270   // Helper to throw a built-in exception.
 271   // Range checks take the offending index.
 272   // Cast and array store checks take the offending class.
 273   // Others do not take the optional argument.
 274   // The JVMS must allow the bytecode to be re-executed
 275   // via an uncommon trap.
 276   void builtin_throw(Deoptimization::DeoptReason reason, Node* arg = NULL);
 277 
 278   // Helper to check the JavaThread::_should_post_on_exceptions flag
 279   // and branch to an uncommon_trap if it is true (with the specified reason and must_throw)
 280   void uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
 281                                                   bool must_throw) ;
 282 
 283   // Helper Functions for adding debug information
 284   void kill_dead_locals();
 285 #ifdef ASSERT
 286   bool dead_locals_are_killed();
 287 #endif
 288   // The call may deoptimize.  Supply required JVM state as debug info.
 289   // If must_throw is true, the call is guaranteed not to return normally.
 290   void add_safepoint_edges(SafePointNode* call,
 291                            bool must_throw = false);
 292 
 293   // How many stack inputs does the current BC consume?
 294   // And, how does the stack change after the bytecode?
 295   // Returns false if unknown.
 296   bool compute_stack_effects(int& inputs, int& depth);
 297 
 298   // Add a fixed offset to a pointer
 299   Node* basic_plus_adr(Node* base, Node* ptr, intptr_t offset) {
 300     return basic_plus_adr(base, ptr, MakeConX(offset));
 301   }
 302   Node* basic_plus_adr(Node* base, intptr_t offset) {
 303     return basic_plus_adr(base, base, MakeConX(offset));
 304   }
 305   // Add a variable offset to a pointer
 306   Node* basic_plus_adr(Node* base, Node* offset) {
 307     return basic_plus_adr(base, base, offset);
 308   }
 309   Node* basic_plus_adr(Node* base, Node* ptr, Node* offset);
 310 
 311 
 312   // Some convenient shortcuts for common nodes
 313   Node* IfTrue(IfNode* iff)                   { return _gvn.transform(new IfTrueNode(iff));      }
 314   Node* IfFalse(IfNode* iff)                  { return _gvn.transform(new IfFalseNode(iff));     }
 315 
 316   Node* AddI(Node* l, Node* r)                { return _gvn.transform(new AddINode(l, r));       }
 317   Node* SubI(Node* l, Node* r)                { return _gvn.transform(new SubINode(l, r));       }
 318   Node* MulI(Node* l, Node* r)                { return _gvn.transform(new MulINode(l, r));       }
 319   Node* DivI(Node* ctl, Node* l, Node* r)     { return _gvn.transform(new DivINode(ctl, l, r));  }
 320 
 321   Node* AndI(Node* l, Node* r)                { return _gvn.transform(new AndINode(l, r));       }
 322   Node* OrI(Node* l, Node* r)                 { return _gvn.transform(new OrINode(l, r));        }
 323   Node* XorI(Node* l, Node* r)                { return _gvn.transform(new XorINode(l, r));       }
 324 
 325   Node* MaxI(Node* l, Node* r)                { return _gvn.transform(new MaxINode(l, r));       }
 326   Node* MinI(Node* l, Node* r)                { return _gvn.transform(new MinINode(l, r));       }
 327 
 328   Node* LShiftI(Node* l, Node* r)             { return _gvn.transform(new LShiftINode(l, r));    }
 329   Node* RShiftI(Node* l, Node* r)             { return _gvn.transform(new RShiftINode(l, r));    }
 330   Node* URShiftI(Node* l, Node* r)            { return _gvn.transform(new URShiftINode(l, r));   }
 331 
 332   Node* CmpI(Node* l, Node* r)                { return _gvn.transform(new CmpINode(l, r));       }
 333   Node* CmpL(Node* l, Node* r)                { return _gvn.transform(new CmpLNode(l, r));       }
 334   Node* CmpP(Node* l, Node* r)                { return _gvn.transform(new CmpPNode(l, r));       }
 335   Node* Bool(Node* cmp, BoolTest::mask relop) { return _gvn.transform(new BoolNode(cmp, relop)); }
 336 
 337   Node* AddP(Node* b, Node* a, Node* o)       { return _gvn.transform(new AddPNode(b, a, o));    }
 338 
 339   // Convert between int and long, and size_t.
 340   // (See macros ConvI2X, etc., in type.hpp for ConvI2X, etc.)
 341   Node* ConvI2L(Node* offset);
 342   Node* ConvI2UL(Node* offset);
 343   Node* ConvL2I(Node* offset);
 344   // Find out the klass of an object.
 345   Node* load_object_klass(Node* object);
 346   // Find out the length of an array.
 347   Node* load_array_length(Node* array);
 348 
 349 
 350   // Helper function to do a NULL pointer check or ZERO check based on type.
 351   // Throw an exception if a given value is null.
 352   // Return the value cast to not-null.
 353   // Be clever about equivalent dominating null checks.
 354   Node* null_check_common(Node* value, BasicType type,
 355                           bool assert_null = false,
 356                           Node* *null_control = NULL,
 357                           bool speculative = false);
 358   Node* null_check(Node* value, BasicType type = T_OBJECT) {
 359     return null_check_common(value, type, false, NULL, !_gvn.type(value)->speculative_maybe_null());
 360   }
 361   Node* null_check_receiver() {
 362     assert(argument(0)->bottom_type()->isa_ptr(), "must be");
 363     return null_check(argument(0));
 364   }
 365   Node* zero_check_int(Node* value) {
 366     assert(value->bottom_type()->basic_type() == T_INT,
 367            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
 368     return null_check_common(value, T_INT);
 369   }
 370   Node* zero_check_long(Node* value) {
 371     assert(value->bottom_type()->basic_type() == T_LONG,
 372            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
 373     return null_check_common(value, T_LONG);
 374   }
 375   // Throw an uncommon trap if a given value is __not__ null.
 376   // Return the value cast to null, and be clever about dominating checks.
 377   Node* null_assert(Node* value, BasicType type = T_OBJECT) {
 378     return null_check_common(value, type, true, NULL, _gvn.type(value)->speculative_always_null());
 379   }
 380 
 381   Node* null2default(Node* value, ciValueKlass* vk = NULL);
 382 
 383   // Check if value is null and abort if it is
 384   Node* must_be_not_null(Node* value, bool do_replace_in_map);
 385 
 386   // Null check oop.  Return null-path control into (*null_control).
 387   // Return a cast-not-null node which depends on the not-null control.
 388   // If never_see_null, use an uncommon trap (*null_control sees a top).
 389   // The cast is not valid along the null path; keep a copy of the original.
 390   // If safe_for_replace, then we can replace the value with the cast
 391   // in the parsing map (the cast is guaranteed to dominate the map)
 392   Node* null_check_oop(Node* value, Node* *null_control,
 393                        bool never_see_null = false,
 394                        bool safe_for_replace = false,
 395                        bool speculative = false);
 396 
 397   // Check the null_seen bit.
 398   bool seems_never_null(Node* obj, ciProfileData* data, bool& speculating);
 399 
 400   void guard_klass_being_initialized(Node* klass);
 401   void guard_init_thread(Node* klass);
 402 
 403   void clinit_barrier(ciInstanceKlass* ik, ciMethod* context);
 404 
 405   // Check for unique class for receiver at call
 406   ciKlass* profile_has_unique_klass() {
 407     ciCallProfile profile = method()->call_profile_at_bci(bci());
 408     if (profile.count() >= 0 &&         // no cast failures here
 409         profile.has_receiver(0) &&
 410         profile.morphism() == 1) {
 411       return profile.receiver(0);
 412     }
 413     return NULL;
 414   }
 415 
 416   // record type from profiling with the type system
 417   Node* record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind);
 418   void record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc);
 419   void record_profiled_parameters_for_speculation();
 420   void record_profiled_return_for_speculation();
 421   Node* record_profiled_receiver_for_speculation(Node* n);
 422 
 423   // Use the type profile to narrow an object type.
 424   Node* maybe_cast_profiled_receiver(Node* not_null_obj,
 425                                      ciKlass* require_klass,
 426                                      ciKlass* spec,
 427                                      bool safe_for_replace);
 428 
 429   // Cast obj to type and emit guard unless we had too many traps here already
 430   Node* maybe_cast_profiled_obj(Node* obj,
 431                                 ciKlass* type,
 432                                 bool not_null = false);
 433 
 434   // Cast obj to not-null on this path
 435   Node* cast_not_null(Node* obj, bool do_replace_in_map = true);
 436   // Replace all occurrences of one node by another.
 437   void replace_in_map(Node* old, Node* neww);
 438 
 439   void  push(Node* n)     { map_not_null();        _map->set_stack(_map->_jvms,   _sp++        , n); }
 440   Node* pop()             { map_not_null(); return _map->stack(    _map->_jvms, --_sp             ); }
 441   Node* peek(int off = 0) { map_not_null(); return _map->stack(    _map->_jvms,   _sp - off - 1   ); }
 442 
 443   void push_pair(Node* ldval) {
 444     push(ldval);
 445     push(top());  // the halfword is merely a placeholder
 446   }
 447   void push_pair_local(int i) {
 448     // longs are stored in locals in "push" order
 449     push(  local(i+0) );  // the real value
 450     assert(local(i+1) == top(), "");
 451     push(top());  // halfword placeholder
 452   }
 453   Node* pop_pair() {
 454     // the second half is pushed last & popped first; it contains exactly nothing
 455     Node* halfword = pop();
 456     assert(halfword == top(), "");
 457     // the long bits are pushed first & popped last:
 458     return pop();
 459   }
 460   void set_pair_local(int i, Node* lval) {
 461     // longs are stored in locals as a value/half pair (like doubles)
 462     set_local(i+0, lval);
 463     set_local(i+1, top());
 464   }
 465 
 466   // Push the node, which may be zero, one, or two words.
 467   void push_node(BasicType n_type, Node* n) {
 468     int n_size = type2size[n_type];
 469     if      (n_size == 1)  push(      n );  // T_INT, ...
 470     else if (n_size == 2)  push_pair( n );  // T_DOUBLE, T_LONG
 471     else                   { assert(n_size == 0, "must be T_VOID"); }
 472   }
 473 
 474   Node* pop_node(BasicType n_type) {
 475     int n_size = type2size[n_type];
 476     if      (n_size == 1)  return pop();
 477     else if (n_size == 2)  return pop_pair();
 478     else                   return NULL;
 479   }
 480 
 481   Node* control()               const { return map_not_null()->control(); }
 482   Node* i_o()                   const { return map_not_null()->i_o(); }
 483   Node* returnadr()             const { return map_not_null()->returnadr(); }
 484   Node* frameptr()              const { return map_not_null()->frameptr(); }
 485   Node* local(uint idx)         const { map_not_null(); return _map->local(      _map->_jvms, idx); }
 486   Node* stack(uint idx)         const { map_not_null(); return _map->stack(      _map->_jvms, idx); }
 487   Node* argument(uint idx)      const { map_not_null(); return _map->argument(   _map->_jvms, idx); }
 488   Node* monitor_box(uint idx)   const { map_not_null(); return _map->monitor_box(_map->_jvms, idx); }
 489   Node* monitor_obj(uint idx)   const { map_not_null(); return _map->monitor_obj(_map->_jvms, idx); }
 490 
 491   void set_control  (Node* c)         { map_not_null()->set_control(c); }
 492   void set_i_o      (Node* c)         { map_not_null()->set_i_o(c); }
 493   void set_local(uint idx, Node* c)   { map_not_null(); _map->set_local(   _map->_jvms, idx, c); }
 494   void set_stack(uint idx, Node* c)   { map_not_null(); _map->set_stack(   _map->_jvms, idx, c); }
 495   void set_argument(uint idx, Node* c){ map_not_null(); _map->set_argument(_map->_jvms, idx, c); }
 496   void ensure_stack(uint stk_size)    { map_not_null(); _map->ensure_stack(_map->_jvms, stk_size); }
 497 
 498   // Access unaliased memory
 499   Node* memory(uint alias_idx);
 500   Node* memory(const TypePtr *tp) { return memory(C->get_alias_index(tp)); }
 501   Node* memory(Node* adr) { return memory(_gvn.type(adr)->is_ptr()); }
 502 
 503   // Access immutable memory
 504   Node* immutable_memory() { return C->immutable_memory(); }
 505 
 506   // Set unaliased memory
 507   void set_memory(Node* c, uint alias_idx) { merged_memory()->set_memory_at(alias_idx, c); }
 508   void set_memory(Node* c, const TypePtr *tp) { set_memory(c,C->get_alias_index(tp)); }
 509   void set_memory(Node* c, Node* adr) { set_memory(c,_gvn.type(adr)->is_ptr()); }
 510 
 511   // Get the entire memory state (probably a MergeMemNode), and reset it
 512   // (The resetting prevents somebody from using the dangling Node pointer.)
 513   Node* reset_memory();
 514 
 515   // Get the entire memory state, asserted to be a MergeMemNode.
 516   MergeMemNode* merged_memory() {
 517     Node* mem = map_not_null()->memory();
 518     assert(mem->is_MergeMem(), "parse memory is always pre-split");
 519     return mem->as_MergeMem();
 520   }
 521 
 522   // Set the entire memory state; produce a new MergeMemNode.
 523   void set_all_memory(Node* newmem);
 524 
 525   // Create a memory projection from the call, then set_all_memory.
 526   void set_all_memory_call(Node* call, bool separate_io_proj = false);
 527 
 528   // Create a LoadNode, reading from the parser's memory state.
 529   // (Note:  require_atomic_access is useful only with T_LONG.)
 530   //
 531   // We choose the unordered semantics by default because we have
 532   // adapted the `do_put_xxx' and `do_get_xxx' procedures for the case
 533   // of volatile fields.
 534   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
 535                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
 536                   bool require_atomic_access = false, bool unaligned = false,
 537                   bool mismatched = false, bool unsafe = false) {
 538     // This version computes alias_index from bottom_type
 539     return make_load(ctl, adr, t, bt, adr->bottom_type()->is_ptr(),
 540                      mo, control_dependency, require_atomic_access,
 541                      unaligned, mismatched, unsafe);
 542   }
 543   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, const TypePtr* adr_type,
 544                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
 545                   bool require_atomic_access = false, bool unaligned = false,
 546                   bool mismatched = false, bool unsafe = false) {
 547     // This version computes alias_index from an address type
 548     assert(adr_type != NULL, "use other make_load factory");
 549     return make_load(ctl, adr, t, bt, C->get_alias_index(adr_type),
 550                      mo, control_dependency, require_atomic_access,
 551                      unaligned, mismatched, unsafe);
 552   }
 553   // This is the base version which is given an alias index.
 554   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, int adr_idx,
 555                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
 556                   bool require_atomic_access = false, bool unaligned = false,
 557                   bool mismatched = false, bool unsafe = false);
 558 
 559   // Create & transform a StoreNode and store the effect into the
 560   // parser's memory state.
 561   //
 562   // We must ensure that stores of object references will be visible
 563   // only after the object's initialization. So the clients of this
 564   // procedure must indicate that the store requires `release'
 565   // semantics, if the stored value is an object reference that might
 566   // point to a new object and may become externally visible.
 567   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
 568                         const TypePtr* adr_type,
 569                         MemNode::MemOrd mo,
 570                         bool require_atomic_access = false,
 571                         bool unaligned = false,
 572                         bool mismatched = false,
 573                         bool unsafe = false) {
 574     // This version computes alias_index from an address type
 575     assert(adr_type != NULL, "use other store_to_memory factory");
 576     return store_to_memory(ctl, adr, val, bt,
 577                            C->get_alias_index(adr_type),
 578                            mo, require_atomic_access,
 579                            unaligned, mismatched, unsafe);
 580   }
 581   // This is the base version which is given alias index
 582   // Return the new StoreXNode
 583   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
 584                         int adr_idx,
 585                         MemNode::MemOrd,
 586                         bool require_atomic_access = false,
 587                         bool unaligned = false,
 588                         bool mismatched = false,
 589                         bool unsafe = false);
 590 
 591   // Perform decorated accesses
 592 
 593   Node* access_store_at(Node* obj,   // containing obj
 594                         Node* adr,   // actual adress to store val at
 595                         const TypePtr* adr_type,
 596                         Node* val,
 597                         const Type* val_type,
 598                         BasicType bt,
 599                         DecoratorSet decorators,
 600                         bool deoptimize_on_exception = false,
 601                         bool safe_for_replace = true);
 602 
 603   Node* access_load_at(Node* obj,   // containing obj
 604                        Node* adr,   // actual adress to load val at
 605                        const TypePtr* adr_type,
 606                        const Type* val_type,
 607                        BasicType bt,
 608                        DecoratorSet decorators,
 609                        Node* ctl = NULL);
 610 
 611   Node* access_load(Node* adr,   // actual adress to load val at
 612                     const Type* val_type,
 613                     BasicType bt,
 614                     DecoratorSet decorators);
 615 
 616   Node* access_atomic_cmpxchg_val_at(Node* obj,
 617                                      Node* adr,
 618                                      const TypePtr* adr_type,
 619                                      int alias_idx,
 620                                      Node* expected_val,
 621                                      Node* new_val,
 622                                      const Type* value_type,
 623                                      BasicType bt,
 624                                      DecoratorSet decorators);
 625 
 626   Node* access_atomic_cmpxchg_bool_at(Node* obj,
 627                                       Node* adr,
 628                                       const TypePtr* adr_type,
 629                                       int alias_idx,
 630                                       Node* expected_val,
 631                                       Node* new_val,
 632                                       const Type* value_type,
 633                                       BasicType bt,
 634                                       DecoratorSet decorators);
 635 
 636   Node* access_atomic_xchg_at(Node* obj,
 637                               Node* adr,
 638                               const TypePtr* adr_type,
 639                               int alias_idx,
 640                               Node* new_val,
 641                               const Type* value_type,
 642                               BasicType bt,
 643                               DecoratorSet decorators);
 644 
 645   Node* access_atomic_add_at(Node* obj,
 646                              Node* adr,
 647                              const TypePtr* adr_type,
 648                              int alias_idx,
 649                              Node* new_val,
 650                              const Type* value_type,
 651                              BasicType bt,
 652                              DecoratorSet decorators);
 653 
 654   void access_clone(Node* src_base, Node* dst_base, Node* countx, bool is_array);
 655 
 656   Node* access_resolve(Node* n, DecoratorSet decorators);
 657 
 658   // Return addressing for an array element.
 659   Node* array_element_address(Node* ary, Node* idx, BasicType elembt,
 660                               // Optional constraint on the array size:
 661                               const TypeInt* sizetype = NULL,
 662                               // Optional control dependency (for example, on range check)
 663                               Node* ctrl = NULL);
 664 
 665   // Return a load of array element at idx.
 666   Node* load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype);
 667 
 668   //---------------- Dtrace support --------------------
 669   void make_dtrace_method_entry_exit(ciMethod* method, bool is_entry);
 670   void make_dtrace_method_entry(ciMethod* method) {
 671     make_dtrace_method_entry_exit(method, true);
 672   }
 673   void make_dtrace_method_exit(ciMethod* method) {
 674     make_dtrace_method_entry_exit(method, false);
 675   }
 676 
 677   //--------------- stub generation -------------------
 678  public:
 679   void gen_stub(address C_function,
 680                 const char *name,
 681                 int is_fancy_jump,
 682                 bool pass_tls,
 683                 bool return_pc);
 684 
 685   //---------- help for generating calls --------------
 686 
 687   // Do a null check on the receiver as it would happen before the call to
 688   // callee (with all arguments still on the stack).
 689   Node* null_check_receiver_before_call(ciMethod* callee, bool replace_value = true) {
 690     assert(!callee->is_static(), "must be a virtual method");
 691     if (argument(0)->is_ValueType()) {
 692       return argument(0);
 693     }
 694     // Callsite signature can be different from actual method being called (i.e _linkTo* sites).
 695     // Use callsite signature always.
 696     ciMethod* declared_method = method()->get_method_at_bci(bci());
 697     const int nargs = declared_method->arg_size();
 698     inc_sp(nargs);
 699     Node* n = null_check_receiver();
 700     dec_sp(nargs);
 701     // Scalarize value type receiver
 702     const Type* recv_type = gvn().type(n);
 703     if (recv_type->is_valuetypeptr() && recv_type->value_klass()->is_scalarizable()) {
 704       assert(!recv_type->maybe_null(), "should never be null");
 705       ValueTypeNode* vt = ValueTypeNode::make_from_oop(this, n, recv_type->value_klass());
 706       set_argument(0, vt);
 707       if (replace_value && !Compile::current()->inlining_incrementally()) {
 708         // Only replace in map if we are not incrementally inlining because we
 709         // share a map with the caller which might expect the value type as oop.
 710         replace_in_map(n, vt);
 711       }
 712       n = vt;
 713     }
 714     return n;
 715   }
 716 
 717   // Fill in argument edges for the call from argument(0), argument(1), ...
 718   // (The next step is to call set_edges_for_java_call.)
 719   void  set_arguments_for_java_call(CallJavaNode* call, bool incremental_inlining = false);
 720 
 721   // Fill in non-argument edges for the call.
 722   // Transform the call, and update the basics: control, i_o, memory.
 723   // (The next step is usually to call set_results_for_java_call.)
 724   void set_edges_for_java_call(CallJavaNode* call,
 725                                bool must_throw = false, bool separate_io_proj = false);
 726 
 727   // Finish up a java call that was started by set_edges_for_java_call.
 728   // Call add_exception on any throw arising from the call.
 729   // Return the call result (transformed).
 730   Node* set_results_for_java_call(CallJavaNode* call, bool separate_io_proj = false, bool deoptimize = false);
 731 
 732   // Similar to set_edges_for_java_call, but simplified for runtime calls.
 733   void  set_predefined_output_for_runtime_call(Node* call) {
 734     set_predefined_output_for_runtime_call(call, NULL, NULL);
 735   }
 736   void  set_predefined_output_for_runtime_call(Node* call,
 737                                                Node* keep_mem,
 738                                                const TypePtr* hook_mem);
 739   Node* set_predefined_input_for_runtime_call(SafePointNode* call, Node* narrow_mem = NULL);
 740 
 741   // Replace the call with the current state of the kit.  Requires
 742   // that the call was generated with separate io_projs so that
 743   // exceptional control flow can be handled properly.
 744   void replace_call(CallNode* call, Node* result, bool do_replaced_nodes = false);
 745 
 746   // helper functions for statistics
 747   void increment_counter(address counter_addr);   // increment a debug counter
 748   void increment_counter(Node*   counter_addr);   // increment a debug counter
 749 
 750   // Bail out to the interpreter right now
 751   // The optional klass is the one causing the trap.
 752   // The optional reason is debug information written to the compile log.
 753   // Optional must_throw is the same as with add_safepoint_edges.
 754   void uncommon_trap(int trap_request,
 755                      ciKlass* klass = NULL, const char* reason_string = NULL,
 756                      bool must_throw = false, bool keep_exact_action = false);
 757 
 758   // Shorthand, to avoid saying "Deoptimization::" so many times.
 759   void uncommon_trap(Deoptimization::DeoptReason reason,
 760                      Deoptimization::DeoptAction action,
 761                      ciKlass* klass = NULL, const char* reason_string = NULL,
 762                      bool must_throw = false, bool keep_exact_action = false) {
 763     uncommon_trap(Deoptimization::make_trap_request(reason, action),
 764                   klass, reason_string, must_throw, keep_exact_action);
 765   }
 766 
 767   // Bail out to the interpreter and keep exact action (avoid switching to Action_none).
 768   void uncommon_trap_exact(Deoptimization::DeoptReason reason,
 769                            Deoptimization::DeoptAction action,
 770                            ciKlass* klass = NULL, const char* reason_string = NULL,
 771                            bool must_throw = false) {
 772     uncommon_trap(Deoptimization::make_trap_request(reason, action),
 773                   klass, reason_string, must_throw, /*keep_exact_action=*/true);
 774   }
 775 
 776   // SP when bytecode needs to be reexecuted.
 777   virtual int reexecute_sp() { return sp(); }
 778 
 779   // Report if there were too many traps at the current method and bci.
 780   // Report if a trap was recorded, and/or PerMethodTrapLimit was exceeded.
 781   // If there is no MDO at all, report no trap unless told to assume it.
 782   bool too_many_traps(Deoptimization::DeoptReason reason) {
 783     return C->too_many_traps(method(), bci(), reason);
 784   }
 785 
 786   // Report if there were too many recompiles at the current method and bci.
 787   bool too_many_recompiles(Deoptimization::DeoptReason reason) {
 788     return C->too_many_recompiles(method(), bci(), reason);
 789   }
 790 
 791   bool too_many_traps_or_recompiles(Deoptimization::DeoptReason reason) {
 792       return C->too_many_traps_or_recompiles(method(), bci(), reason);
 793   }
 794 
 795   // Returns the object (if any) which was created the moment before.
 796   Node* just_allocated_object(Node* current_control);
 797 
 798   // Sync Ideal and Graph kits.
 799   void sync_kit(IdealKit& ideal);
 800   void final_sync(IdealKit& ideal);
 801 
 802   public:
 803   // Helper function to round double arguments before a call
 804   void round_double_arguments(ciMethod* dest_method);
 805   void round_double_result(ciMethod* dest_method);
 806 
 807   // rounding for strict float precision conformance
 808   Node* precision_rounding(Node* n);
 809 
 810   // rounding for strict double precision conformance
 811   Node* dprecision_rounding(Node* n);
 812 
 813   // rounding for non-strict double stores
 814   Node* dstore_rounding(Node* n);
 815 
 816   // Helper functions for fast/slow path codes
 817   Node* opt_iff(Node* region, Node* iff);
 818   Node* make_runtime_call(int flags,
 819                           const TypeFunc* call_type, address call_addr,
 820                           const char* call_name,
 821                           const TypePtr* adr_type, // NULL if no memory effects
 822                           Node* parm0 = NULL, Node* parm1 = NULL,
 823                           Node* parm2 = NULL, Node* parm3 = NULL,
 824                           Node* parm4 = NULL, Node* parm5 = NULL,
 825                           Node* parm6 = NULL, Node* parm7 = NULL);
 826   enum {  // flag values for make_runtime_call
 827     RC_NO_FP = 1,               // CallLeafNoFPNode
 828     RC_NO_IO = 2,               // do not hook IO edges
 829     RC_NO_LEAF = 4,             // CallStaticJavaNode
 830     RC_MUST_THROW = 8,          // flag passed to add_safepoint_edges
 831     RC_NARROW_MEM = 16,         // input memory is same as output
 832     RC_UNCOMMON = 32,           // freq. expected to be like uncommon trap
 833     RC_LEAF = 0                 // null value:  no flags set
 834   };
 835 
 836   // merge in all memory slices from new_mem, along the given path
 837   void merge_memory(Node* new_mem, Node* region, int new_path);
 838   void make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize = false);
 839 
 840   // Helper functions to build synchronizations
 841   int next_monitor();
 842   Node* insert_mem_bar(int opcode, Node* precedent = NULL);
 843   Node* insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent = NULL);
 844   // Optional 'precedent' is appended as an extra edge, to force ordering.
 845   FastLockNode* shared_lock(Node* obj);
 846   void shared_unlock(Node* box, Node* obj);
 847 
 848   // helper functions for the fast path/slow path idioms
 849   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);
 850 
 851   // Generate an instance-of idiom.  Used by both the instance-of bytecode
 852   // and the reflective instance-of call.
 853   Node* gen_instanceof(Node *subobj, Node* superkls, bool safe_for_replace = false);
 854 
 855   // Generate a check-cast idiom.  Used by both the check-cast bytecode
 856   // and the array-store bytecode
 857   Node* gen_checkcast(Node *subobj, Node* superkls, Node* *failure_control = NULL, bool never_null = false);
 858 
 859   Node* is_always_locked(Node* obj);
 860   Node* is_value_mirror(Node* mirror);
 861   void gen_value_type_guard(Node* obj, int nargs = 0);
 862   Node* gen_null_free_array_check(Node* ary);
 863   Node* gen_flattened_array_test(Node* ary);
 864   Node* gen_value_array_null_guard(Node* ary, Node* val, int nargs, bool safe_for_replace = false);
 865   Node* load_lh_array_tag(Node* kls);
 866   Node* gen_lh_array_test(Node* kls, unsigned int lh_value);
 867 
 868   Node* gen_subtype_check(Node* subklass, Node* superklass) {
 869     MergeMemNode* mem = merged_memory();
 870     Node* ctrl = control();
 871     Node* n = Phase::gen_subtype_check(subklass, superklass, &ctrl, mem, &_gvn);
 872     set_control(ctrl);
 873     return n;
 874   }
 875 
 876   // Exact type check used for predicted calls and casts.
 877   // Rewrites (*casted_receiver) to be casted to the stronger type.
 878   // (Caller is responsible for doing replace_in_map.)
 879   Node* type_check_receiver(Node* receiver, ciKlass* klass, float prob,
 880                             Node* *casted_receiver);
 881   Node* type_check(Node* recv_klass, const TypeKlassPtr* tklass, float prob);
 882 
 883   // Inexact type check used for predicted calls.
 884   Node* subtype_check_receiver(Node* receiver, ciKlass* klass,
 885                                Node** casted_receiver);
 886 
 887   // implementation of object creation
 888   Node* set_output_for_allocation(AllocateNode* alloc,
 889                                   const TypeOopPtr* oop_type,
 890                                   bool deoptimize_on_exception=false);
 891   Node* get_layout_helper(Node* klass_node, jint& constant_value);
 892   Node* new_instance(Node* klass_node,
 893                      Node* slow_test = NULL,
 894                      Node* *return_size_val = NULL,
 895                      bool deoptimize_on_exception = false,
 896                      ValueTypeBaseNode* value_node = NULL);
 897   Node* new_array(Node* klass_node, Node* count_val, int nargs,
 898                   Node* *return_size_val = NULL,
 899                   bool deoptimize_on_exception = false,
 900                   Node* elem_mirror = NULL);
 901 
 902   // java.lang.String helpers
 903   Node* load_String_length(Node* str, bool set_ctrl);
 904   Node* load_String_value(Node* str, bool set_ctrl);
 905   Node* load_String_coder(Node* str, bool set_ctrl);
 906   void store_String_value(Node* str, Node* value);
 907   void store_String_coder(Node* str, Node* value);
 908   Node* capture_memory(const TypePtr* src_type, const TypePtr* dst_type);
 909   Node* compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count);
 910   void inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count);
 911   void inflate_string_slow(Node* src, Node* dst, Node* start, Node* count);
 912 
 913   // Handy for making control flow
 914   IfNode* create_and_map_if(Node* ctrl, Node* tst, float prob, float cnt) {
 915     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
 916     _gvn.set_type(iff, iff->Value(&_gvn)); // Value may be known at parse-time
 917     // Place 'if' on worklist if it will be in graph
 918     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
 919     return iff;
 920   }
 921 
 922   IfNode* create_and_xform_if(Node* ctrl, Node* tst, float prob, float cnt) {
 923     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
 924     _gvn.transform(iff);                           // Value may be known at parse-time
 925     // Place 'if' on worklist if it will be in graph
 926     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
 927     return iff;
 928   }
 929 
 930   // Insert a loop predicate into the graph
 931   void add_predicate(int nargs = 0);
 932   void add_predicate_impl(Deoptimization::DeoptReason reason, int nargs);
 933 
 934   Node* make_constant_from_field(ciField* field, Node* obj);
 935 
 936   Node* load_mirror_from_klass(Node* klass);
 937 };
 938 
 939 // Helper class to support building of control flow branches. Upon
 940 // creation the map and sp at bci are cloned and restored upon de-
 941 // struction. Typical use:
 942 //
 943 // { PreserveJVMState pjvms(this);
 944 //   // code of new branch
 945 // }
 946 // // here the JVM state at bci is established
 947 
 948 class PreserveJVMState: public StackObj {
 949  protected:
 950   GraphKit*      _kit;
 951 #ifdef ASSERT
 952   int            _block;  // PO of current block, if a Parse
 953   int            _bci;
 954 #endif
 955   SafePointNode* _map;
 956   uint           _sp;
 957 
 958  public:
 959   PreserveJVMState(GraphKit* kit, bool clone_map = true);
 960   ~PreserveJVMState();
 961 };
 962 
 963 // Helper class to build cutouts of the form if (p) ; else {x...}.
 964 // The code {x...} must not fall through.
 965 // The kit's main flow of control is set to the "then" continuation of if(p).
 966 class BuildCutout: public PreserveJVMState {
 967  public:
 968   BuildCutout(GraphKit* kit, Node* p, float prob, float cnt = COUNT_UNKNOWN);
 969   ~BuildCutout();
 970 };
 971 
 972 // Helper class to preserve the original _reexecute bit and _sp and restore
 973 // them back
 974 class PreserveReexecuteState: public StackObj {
 975  protected:
 976   GraphKit*                 _kit;
 977   uint                      _sp;
 978   JVMState::ReexecuteState  _reexecute;
 979 
 980  public:
 981   PreserveReexecuteState(GraphKit* kit);
 982   ~PreserveReexecuteState();
 983 };
 984 
 985 #endif // SHARE_OPTO_GRAPHKIT_HPP