1 /*
   2  * Copyright (c) 2001, 2012, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
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  23  */
  24 
  25 #ifndef SHARE_VM_OPTO_GRAPHKIT_HPP
  26 #define SHARE_VM_OPTO_GRAPHKIT_HPP
  27 
  28 #include "ci/ciEnv.hpp"
  29 #include "ci/ciMethodData.hpp"
  30 #include "opto/addnode.hpp"
  31 #include "opto/callnode.hpp"
  32 #include "opto/cfgnode.hpp"
  33 #include "opto/compile.hpp"
  34 #include "opto/divnode.hpp"
  35 #include "opto/mulnode.hpp"
  36 #include "opto/phaseX.hpp"
  37 #include "opto/subnode.hpp"
  38 #include "opto/type.hpp"
  39 #include "runtime/deoptimization.hpp"
  40 
  41 class FastLockNode;
  42 class FastUnlockNode;
  43 class IdealKit;
  44 class LibraryCallKit;
  45 class Parse;
  46 class RootNode;
  47 
  48 //-----------------------------------------------------------------------------
  49 //----------------------------GraphKit-----------------------------------------
  50 // Toolkit for building the common sorts of subgraphs.
  51 // Does not know about bytecode parsing or type-flow results.
  52 // It is able to create graphs implementing the semantics of most
  53 // or all bytecodes, so that it can expand intrinsics and calls.
  54 // It may depend on JVMState structure, but it must not depend
  55 // on specific bytecode streams.
  56 class GraphKit : public Phase {
  57   friend class PreserveJVMState;
  58 
  59  protected:
  60   ciEnv*            _env;       // Compilation environment
  61   PhaseGVN         &_gvn;       // Some optimizations while parsing
  62   SafePointNode*    _map;       // Parser map from JVM to Nodes
  63   SafePointNode*    _exceptions;// Parser map(s) for exception state(s)
  64   int               _bci;       // JVM Bytecode Pointer
  65   ciMethod*         _method;    // JVM Current Method
  66 
  67  private:
  68   int               _sp;        // JVM Expression Stack Pointer; don't modify directly!
  69 
  70  private:
  71   SafePointNode*     map_not_null() const {
  72     assert(_map != NULL, "must call stopped() to test for reset compiler map");
  73     return _map;
  74   }
  75 
  76  public:
  77   GraphKit();                   // empty constructor
  78   GraphKit(JVMState* jvms);     // the JVM state on which to operate
  79 
  80 #ifdef ASSERT
  81   ~GraphKit() {
  82     assert(!has_exceptions(), "user must call transfer_exceptions_into_jvms");
  83   }
  84 #endif
  85 
  86   virtual Parse*          is_Parse()          const { return NULL; }
  87   virtual LibraryCallKit* is_LibraryCallKit() const { return NULL; }
  88 
  89   ciEnv*        env()           const { return _env; }
  90   PhaseGVN&     gvn()           const { return _gvn; }
  91 
  92   void record_for_igvn(Node* n) const { C->record_for_igvn(n); }  // delegate to Compile
  93 
  94   // Handy well-known nodes:
  95   Node*         null()          const { return zerocon(T_OBJECT); }
  96   Node*         top()           const { return C->top(); }
  97   RootNode*     root()          const { return C->root(); }
  98 
  99   // Create or find a constant node
 100   Node* intcon(jint con)        const { return _gvn.intcon(con); }
 101   Node* longcon(jlong con)      const { return _gvn.longcon(con); }
 102   Node* makecon(const Type *t)  const { return _gvn.makecon(t); }
 103   Node* zerocon(BasicType bt)   const { return _gvn.zerocon(bt); }
 104   // (See also macro MakeConX in type.hpp, which uses intcon or longcon.)
 105 
 106   // Helper for byte_map_base
 107   Node* byte_map_base_node() {
 108     // Get base of card map
 109     CardTableModRefBS* ct = (CardTableModRefBS*)(Universe::heap()->barrier_set());
 110     assert(sizeof(*ct->byte_map_base) == sizeof(jbyte), "adjust users of this code");
 111     if (ct->byte_map_base != NULL) {
 112       return makecon(TypeRawPtr::make((address)ct->byte_map_base));
 113     } else {
 114       return null();
 115     }
 116   }
 117 
 118   jint  find_int_con(Node* n, jint value_if_unknown) {
 119     return _gvn.find_int_con(n, value_if_unknown);
 120   }
 121   jlong find_long_con(Node* n, jlong value_if_unknown) {
 122     return _gvn.find_long_con(n, value_if_unknown);
 123   }
 124   // (See also macro find_intptr_t_con in type.hpp, which uses one of these.)
 125 
 126   // JVM State accessors:
 127   // Parser mapping from JVM indices into Nodes.
 128   // Low slots are accessed by the StartNode::enum.
 129   // Then come the locals at StartNode::Parms to StartNode::Parms+max_locals();
 130   // Then come JVM stack slots.
 131   // Finally come the monitors, if any.
 132   // See layout accessors in class JVMState.
 133 
 134   SafePointNode*     map()      const { return _map; }
 135   bool               has_exceptions() const { return _exceptions != NULL; }
 136   JVMState*          jvms()     const { return map_not_null()->_jvms; }
 137   int                sp()       const { return _sp; }
 138   int                bci()      const { return _bci; }
 139   Bytecodes::Code    java_bc()  const;
 140   ciMethod*          method()   const { return _method; }
 141 
 142   void set_jvms(JVMState* jvms)       { set_map(jvms->map());
 143                                         assert(jvms == this->jvms(), "sanity");
 144                                         _sp = jvms->sp();
 145                                         _bci = jvms->bci();
 146                                         _method = jvms->has_method() ? jvms->method() : NULL; }
 147   void set_map(SafePointNode* m)      { _map = m; debug_only(verify_map()); }
 148   void set_sp(int sp)                 { assert(sp >= 0, err_msg_res("sp must be non-negative: %d", sp)); _sp = sp; }
 149   void clean_stack(int from_sp); // clear garbage beyond from_sp to top
 150 
 151   void inc_sp(int i)                  { set_sp(sp() + i); }
 152   void dec_sp(int i)                  { set_sp(sp() - i); }
 153   void set_bci(int bci)               { _bci = bci; }
 154 
 155   // Make sure jvms has current bci & sp.
 156   JVMState* sync_jvms() const;
 157   JVMState* sync_jvms_for_reexecute();
 158 
 159 #ifdef ASSERT
 160   // Make sure JVMS has an updated copy of bci and sp.
 161   // Also sanity-check method, depth, and monitor depth.
 162   bool jvms_in_sync() const;
 163 
 164   // Make sure the map looks OK.
 165   void verify_map() const;
 166 
 167   // Make sure a proposed exception state looks OK.
 168   static void verify_exception_state(SafePointNode* ex_map);
 169 #endif
 170 
 171   // Clone the existing map state.  (Implements PreserveJVMState.)
 172   SafePointNode* clone_map();
 173 
 174   // Set the map to a clone of the given one.
 175   void set_map_clone(SafePointNode* m);
 176 
 177   // Tell if the compilation is failing.
 178   bool failing() const { return C->failing(); }
 179 
 180   // Set _map to NULL, signalling a stop to further bytecode execution.
 181   // Preserve the map intact for future use, and return it back to the caller.
 182   SafePointNode* stop() { SafePointNode* m = map(); set_map(NULL); return m; }
 183 
 184   // Stop, but first smash the map's inputs to NULL, to mark it dead.
 185   void stop_and_kill_map();
 186 
 187   // Tell if _map is NULL, or control is top.
 188   bool stopped();
 189 
 190   // Tell if this method or any caller method has exception handlers.
 191   bool has_ex_handler();
 192 
 193   // Save an exception without blowing stack contents or other JVM state.
 194   // (The extra pointer is stuck with add_req on the map, beyond the JVMS.)
 195   static void set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop);
 196 
 197   // Recover a saved exception from its map.
 198   static Node* saved_ex_oop(SafePointNode* ex_map);
 199 
 200   // Recover a saved exception from its map, and remove it from the map.
 201   static Node* clear_saved_ex_oop(SafePointNode* ex_map);
 202 
 203 #ifdef ASSERT
 204   // Recover a saved exception from its map, and remove it from the map.
 205   static bool has_saved_ex_oop(SafePointNode* ex_map);
 206 #endif
 207 
 208   // Push an exception in the canonical position for handlers (stack(0)).
 209   void push_ex_oop(Node* ex_oop) {
 210     ensure_stack(1);  // ensure room to push the exception
 211     set_stack(0, ex_oop);
 212     set_sp(1);
 213     clean_stack(1);
 214   }
 215 
 216   // Detach and return an exception state.
 217   SafePointNode* pop_exception_state() {
 218     SafePointNode* ex_map = _exceptions;
 219     if (ex_map != NULL) {
 220       _exceptions = ex_map->next_exception();
 221       ex_map->set_next_exception(NULL);
 222       debug_only(verify_exception_state(ex_map));
 223     }
 224     return ex_map;
 225   }
 226 
 227   // Add an exception, using the given JVM state, without commoning.
 228   void push_exception_state(SafePointNode* ex_map) {
 229     debug_only(verify_exception_state(ex_map));
 230     ex_map->set_next_exception(_exceptions);
 231     _exceptions = ex_map;
 232   }
 233 
 234   // Turn the current JVM state into an exception state, appending the ex_oop.
 235   SafePointNode* make_exception_state(Node* ex_oop);
 236 
 237   // Add an exception, using the given JVM state.
 238   // Combine all exceptions with a common exception type into a single state.
 239   // (This is done via combine_exception_states.)
 240   void add_exception_state(SafePointNode* ex_map);
 241 
 242   // Combine all exceptions of any sort whatever into a single master state.
 243   SafePointNode* combine_and_pop_all_exception_states() {
 244     if (_exceptions == NULL)  return NULL;
 245     SafePointNode* phi_map = pop_exception_state();
 246     SafePointNode* ex_map;
 247     while ((ex_map = pop_exception_state()) != NULL) {
 248       combine_exception_states(ex_map, phi_map);
 249     }
 250     return phi_map;
 251   }
 252 
 253   // Combine the two exception states, building phis as necessary.
 254   // The second argument is updated to include contributions from the first.
 255   void combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map);
 256 
 257   // Reset the map to the given state.  If there are any half-finished phis
 258   // in it (created by combine_exception_states), transform them now.
 259   // Returns the exception oop.  (Caller must call push_ex_oop if required.)
 260   Node* use_exception_state(SafePointNode* ex_map);
 261 
 262   // Collect exceptions from a given JVM state into my exception list.
 263   void add_exception_states_from(JVMState* jvms);
 264 
 265   // Collect all raised exceptions into the current JVM state.
 266   // Clear the current exception list and map, returns the combined states.
 267   JVMState* transfer_exceptions_into_jvms();
 268 
 269   // Helper to throw a built-in exception.
 270   // Range checks take the offending index.
 271   // Cast and array store checks take the offending class.
 272   // Others do not take the optional argument.
 273   // The JVMS must allow the bytecode to be re-executed
 274   // via an uncommon trap.
 275   void builtin_throw(Deoptimization::DeoptReason reason, Node* arg = NULL);
 276 
 277   // Helper to check the JavaThread::_should_post_on_exceptions flag
 278   // and branch to an uncommon_trap if it is true (with the specified reason and must_throw)
 279   void uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
 280                                                   bool must_throw) ;
 281 
 282   // Helper Functions for adding debug information
 283   void kill_dead_locals();
 284 #ifdef ASSERT
 285   bool dead_locals_are_killed();
 286 #endif
 287   // The call may deoptimize.  Supply required JVM state as debug info.
 288   // If must_throw is true, the call is guaranteed not to return normally.
 289   void add_safepoint_edges(SafePointNode* call,
 290                            bool must_throw = false);
 291 
 292   // How many stack inputs does the current BC consume?
 293   // And, how does the stack change after the bytecode?
 294   // Returns false if unknown.
 295   bool compute_stack_effects(int& inputs, int& depth);
 296 
 297   // Add a fixed offset to a pointer
 298   Node* basic_plus_adr(Node* base, Node* ptr, intptr_t offset) {
 299     return basic_plus_adr(base, ptr, MakeConX(offset));
 300   }
 301   Node* basic_plus_adr(Node* base, intptr_t offset) {
 302     return basic_plus_adr(base, base, MakeConX(offset));
 303   }
 304   // Add a variable offset to a pointer
 305   Node* basic_plus_adr(Node* base, Node* offset) {
 306     return basic_plus_adr(base, base, offset);
 307   }
 308   Node* basic_plus_adr(Node* base, Node* ptr, Node* offset);
 309 
 310 
 311   // Some convenient shortcuts for common nodes
 312   Node* IfTrue(IfNode* iff)                   { return _gvn.transform(new (C) IfTrueNode(iff));      }
 313   Node* IfFalse(IfNode* iff)                  { return _gvn.transform(new (C) IfFalseNode(iff));     }
 314 
 315   Node* AddI(Node* l, Node* r)                { return _gvn.transform(new (C) AddINode(l, r));       }
 316   Node* SubI(Node* l, Node* r)                { return _gvn.transform(new (C) SubINode(l, r));       }
 317   Node* MulI(Node* l, Node* r)                { return _gvn.transform(new (C) MulINode(l, r));       }
 318   Node* DivI(Node* ctl, Node* l, Node* r)     { return _gvn.transform(new (C) DivINode(ctl, l, r));  }
 319 
 320   Node* AndI(Node* l, Node* r)                { return _gvn.transform(new (C) AndINode(l, r));       }
 321   Node* OrI(Node* l, Node* r)                 { return _gvn.transform(new (C) OrINode(l, r));        }
 322   Node* XorI(Node* l, Node* r)                { return _gvn.transform(new (C) XorINode(l, r));       }
 323 
 324   Node* MaxI(Node* l, Node* r)                { return _gvn.transform(new (C) MaxINode(l, r));       }
 325   Node* MinI(Node* l, Node* r)                { return _gvn.transform(new (C) MinINode(l, r));       }
 326 
 327   Node* LShiftI(Node* l, Node* r)             { return _gvn.transform(new (C) LShiftINode(l, r));    }
 328   Node* RShiftI(Node* l, Node* r)             { return _gvn.transform(new (C) RShiftINode(l, r));    }
 329   Node* URShiftI(Node* l, Node* r)            { return _gvn.transform(new (C) URShiftINode(l, r));   }
 330 
 331   Node* CmpI(Node* l, Node* r)                { return _gvn.transform(new (C) CmpINode(l, r));       }
 332   Node* CmpL(Node* l, Node* r)                { return _gvn.transform(new (C) CmpLNode(l, r));       }
 333   Node* CmpP(Node* l, Node* r)                { return _gvn.transform(new (C) CmpPNode(l, r));       }
 334   Node* Bool(Node* cmp, BoolTest::mask relop) { return _gvn.transform(new (C) BoolNode(cmp, relop)); }
 335 
 336   Node* AddP(Node* b, Node* a, Node* o)       { return _gvn.transform(new (C) AddPNode(b, a, o));    }
 337 
 338   // Convert between int and long, and size_t.
 339   // (See macros ConvI2X, etc., in type.hpp for ConvI2X, etc.)
 340   Node* ConvI2L(Node* offset);
 341   Node* ConvL2I(Node* offset);
 342   // Find out the klass of an object.
 343   Node* load_object_klass(Node* object);
 344   // Find out the length of an array.
 345   Node* load_array_length(Node* array);
 346 
 347 
 348   // Helper function to do a NULL pointer check or ZERO check based on type.
 349   // Throw an exception if a given value is null.
 350   // Return the value cast to not-null.
 351   // Be clever about equivalent dominating null checks.
 352   Node* null_check_common(Node* value, BasicType type,
 353                           bool assert_null = false, Node* *null_control = NULL);
 354   Node* null_check(Node* value, BasicType type = T_OBJECT) {
 355     return null_check_common(value, type);
 356   }
 357   Node* null_check_receiver() {
 358     assert(argument(0)->bottom_type()->isa_ptr(), "must be");
 359     return null_check(argument(0));
 360   }
 361   Node* zero_check_int(Node* value) {
 362     assert(value->bottom_type()->basic_type() == T_INT,
 363         err_msg_res("wrong type: %s", type2name(value->bottom_type()->basic_type())));
 364     return null_check_common(value, T_INT);
 365   }
 366   Node* zero_check_long(Node* value) {
 367     assert(value->bottom_type()->basic_type() == T_LONG,
 368         err_msg_res("wrong type: %s", type2name(value->bottom_type()->basic_type())));
 369     return null_check_common(value, T_LONG);
 370   }
 371   // Throw an uncommon trap if a given value is __not__ null.
 372   // Return the value cast to null, and be clever about dominating checks.
 373   Node* null_assert(Node* value, BasicType type = T_OBJECT) {
 374     return null_check_common(value, type, true);
 375   }
 376 
 377   // Null check oop.  Return null-path control into (*null_control).
 378   // Return a cast-not-null node which depends on the not-null control.
 379   // If never_see_null, use an uncommon trap (*null_control sees a top).
 380   // The cast is not valid along the null path; keep a copy of the original.
 381   Node* null_check_oop(Node* value, Node* *null_control,
 382                        bool never_see_null = false);
 383 
 384   // Check the null_seen bit.
 385   bool seems_never_null(Node* obj, ciProfileData* data);
 386 
 387   // Use the type profile to narrow an object type.
 388   Node* maybe_cast_profiled_receiver(Node* not_null_obj,
 389                                      ciProfileData* data,
 390                                      ciKlass* require_klass);
 391 
 392   // Cast obj to not-null on this path
 393   Node* cast_not_null(Node* obj, bool do_replace_in_map = true);
 394   // Replace all occurrences of one node by another.
 395   void replace_in_map(Node* old, Node* neww);
 396 
 397   void  push(Node* n)     { map_not_null();        _map->set_stack(_map->_jvms,   _sp++        , n); }
 398   Node* pop()             { map_not_null(); return _map->stack(    _map->_jvms, --_sp             ); }
 399   Node* peek(int off = 0) { map_not_null(); return _map->stack(    _map->_jvms,   _sp - off - 1   ); }
 400 
 401   void push_pair(Node* ldval) {
 402     push(ldval);
 403     push(top());  // the halfword is merely a placeholder
 404   }
 405   void push_pair_local(int i) {
 406     // longs are stored in locals in "push" order
 407     push(  local(i+0) );  // the real value
 408     assert(local(i+1) == top(), "");
 409     push(top());  // halfword placeholder
 410   }
 411   Node* pop_pair() {
 412     // the second half is pushed last & popped first; it contains exactly nothing
 413     Node* halfword = pop();
 414     assert(halfword == top(), "");
 415     // the long bits are pushed first & popped last:
 416     return pop();
 417   }
 418   void set_pair_local(int i, Node* lval) {
 419     // longs are stored in locals as a value/half pair (like doubles)
 420     set_local(i+0, lval);
 421     set_local(i+1, top());
 422   }
 423 
 424   // Push the node, which may be zero, one, or two words.
 425   void push_node(BasicType n_type, Node* n) {
 426     int n_size = type2size[n_type];
 427     if      (n_size == 1)  push(      n );  // T_INT, ...
 428     else if (n_size == 2)  push_pair( n );  // T_DOUBLE, T_LONG
 429     else                   { assert(n_size == 0, "must be T_VOID"); }
 430   }
 431 
 432   Node* pop_node(BasicType n_type) {
 433     int n_size = type2size[n_type];
 434     if      (n_size == 1)  return pop();
 435     else if (n_size == 2)  return pop_pair();
 436     else                   return NULL;
 437   }
 438 
 439   Node* control()               const { return map_not_null()->control(); }
 440   Node* i_o()                   const { return map_not_null()->i_o(); }
 441   Node* returnadr()             const { return map_not_null()->returnadr(); }
 442   Node* frameptr()              const { return map_not_null()->frameptr(); }
 443   Node* local(uint idx)         const { map_not_null(); return _map->local(      _map->_jvms, idx); }
 444   Node* stack(uint idx)         const { map_not_null(); return _map->stack(      _map->_jvms, idx); }
 445   Node* argument(uint idx)      const { map_not_null(); return _map->argument(   _map->_jvms, idx); }
 446   Node* monitor_box(uint idx)   const { map_not_null(); return _map->monitor_box(_map->_jvms, idx); }
 447   Node* monitor_obj(uint idx)   const { map_not_null(); return _map->monitor_obj(_map->_jvms, idx); }
 448 
 449   void set_control  (Node* c)         { map_not_null()->set_control(c); }
 450   void set_i_o      (Node* c)         { map_not_null()->set_i_o(c); }
 451   void set_local(uint idx, Node* c)   { map_not_null(); _map->set_local(   _map->_jvms, idx, c); }
 452   void set_stack(uint idx, Node* c)   { map_not_null(); _map->set_stack(   _map->_jvms, idx, c); }
 453   void set_argument(uint idx, Node* c){ map_not_null(); _map->set_argument(_map->_jvms, idx, c); }
 454   void ensure_stack(uint stk_size)    { map_not_null(); _map->ensure_stack(_map->_jvms, stk_size); }
 455 
 456   // Access unaliased memory
 457   Node* memory(uint alias_idx);
 458   Node* memory(const TypePtr *tp) { return memory(C->get_alias_index(tp)); }
 459   Node* memory(Node* adr) { return memory(_gvn.type(adr)->is_ptr()); }
 460 
 461   // Access immutable memory
 462   Node* immutable_memory() { return C->immutable_memory(); }
 463 
 464   // Set unaliased memory
 465   void set_memory(Node* c, uint alias_idx) { merged_memory()->set_memory_at(alias_idx, c); }
 466   void set_memory(Node* c, const TypePtr *tp) { set_memory(c,C->get_alias_index(tp)); }
 467   void set_memory(Node* c, Node* adr) { set_memory(c,_gvn.type(adr)->is_ptr()); }
 468 
 469   // Get the entire memory state (probably a MergeMemNode), and reset it
 470   // (The resetting prevents somebody from using the dangling Node pointer.)
 471   Node* reset_memory();
 472 
 473   // Get the entire memory state, asserted to be a MergeMemNode.
 474   MergeMemNode* merged_memory() {
 475     Node* mem = map_not_null()->memory();
 476     assert(mem->is_MergeMem(), "parse memory is always pre-split");
 477     return mem->as_MergeMem();
 478   }
 479 
 480   // Set the entire memory state; produce a new MergeMemNode.
 481   void set_all_memory(Node* newmem);
 482 
 483   // Create a memory projection from the call, then set_all_memory.
 484   void set_all_memory_call(Node* call, bool separate_io_proj = false);
 485 
 486   // Create a LoadNode, reading from the parser's memory state.
 487   // (Note:  require_atomic_access is useful only with T_LONG.)
 488   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
 489                   bool require_atomic_access = false) {
 490     // This version computes alias_index from bottom_type
 491     return make_load(ctl, adr, t, bt, adr->bottom_type()->is_ptr(),
 492                      require_atomic_access);
 493   }
 494   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, const TypePtr* adr_type, bool require_atomic_access = false) {
 495     // This version computes alias_index from an address type
 496     assert(adr_type != NULL, "use other make_load factory");
 497     return make_load(ctl, adr, t, bt, C->get_alias_index(adr_type),
 498                      require_atomic_access);
 499   }
 500   // This is the base version which is given an alias index.
 501   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, int adr_idx, bool require_atomic_access = false);
 502 
 503   // Create & transform a StoreNode and store the effect into the
 504   // parser's memory state.
 505   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
 506                         const TypePtr* adr_type,
 507                         bool require_atomic_access = false) {
 508     // This version computes alias_index from an address type
 509     assert(adr_type != NULL, "use other store_to_memory factory");
 510     return store_to_memory(ctl, adr, val, bt,
 511                            C->get_alias_index(adr_type),
 512                            require_atomic_access);
 513   }
 514   // This is the base version which is given alias index
 515   // Return the new StoreXNode
 516   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
 517                         int adr_idx,
 518                         bool require_atomic_access = false);
 519 
 520 
 521   // All in one pre-barrier, store, post_barrier
 522   // Insert a write-barrier'd store.  This is to let generational GC
 523   // work; we have to flag all oop-stores before the next GC point.
 524   //
 525   // It comes in 3 flavors of store to an object, array, or unknown.
 526   // We use precise card marks for arrays to avoid scanning the entire
 527   // array. We use imprecise for object. We use precise for unknown
 528   // since we don't know if we have an array or and object or even
 529   // where the object starts.
 530   //
 531   // If val==NULL, it is taken to be a completely unknown value. QQQ
 532 
 533   Node* store_oop(Node* ctl,
 534                   Node* obj,   // containing obj
 535                   Node* adr,  // actual adress to store val at
 536                   const TypePtr* adr_type,
 537                   Node* val,
 538                   const TypeOopPtr* val_type,
 539                   BasicType bt,
 540                   bool use_precise);
 541 
 542   Node* store_oop_to_object(Node* ctl,
 543                             Node* obj,   // containing obj
 544                             Node* adr,  // actual adress to store val at
 545                             const TypePtr* adr_type,
 546                             Node* val,
 547                             const TypeOopPtr* val_type,
 548                             BasicType bt) {
 549     return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, false);
 550   }
 551 
 552   Node* store_oop_to_array(Node* ctl,
 553                            Node* obj,   // containing obj
 554                            Node* adr,  // actual adress to store val at
 555                            const TypePtr* adr_type,
 556                            Node* val,
 557                            const TypeOopPtr* val_type,
 558                            BasicType bt) {
 559     return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true);
 560   }
 561 
 562   // Could be an array or object we don't know at compile time (unsafe ref.)
 563   Node* store_oop_to_unknown(Node* ctl,
 564                              Node* obj,   // containing obj
 565                              Node* adr,  // actual adress to store val at
 566                              const TypePtr* adr_type,
 567                              Node* val,
 568                              BasicType bt);
 569 
 570   // For the few case where the barriers need special help
 571   void pre_barrier(bool do_load, Node* ctl,
 572                    Node* obj, Node* adr, uint adr_idx, Node* val, const TypeOopPtr* val_type,
 573                    Node* pre_val,
 574                    BasicType bt);
 575 
 576   void post_barrier(Node* ctl, Node* store, Node* obj, Node* adr, uint adr_idx,
 577                     Node* val, BasicType bt, bool use_precise);
 578 
 579   // Return addressing for an array element.
 580   Node* array_element_address(Node* ary, Node* idx, BasicType elembt,
 581                               // Optional constraint on the array size:
 582                               const TypeInt* sizetype = NULL);
 583 
 584   // Return a load of array element at idx.
 585   Node* load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype);
 586 
 587   //---------------- Dtrace support --------------------
 588   void make_dtrace_method_entry_exit(ciMethod* method, bool is_entry);
 589   void make_dtrace_method_entry(ciMethod* method) {
 590     make_dtrace_method_entry_exit(method, true);
 591   }
 592   void make_dtrace_method_exit(ciMethod* method) {
 593     make_dtrace_method_entry_exit(method, false);
 594   }
 595 
 596   //--------------- stub generation -------------------
 597  public:
 598   void gen_stub(address C_function,
 599                 const char *name,
 600                 int is_fancy_jump,
 601                 bool pass_tls,
 602                 bool return_pc);
 603 
 604   //---------- help for generating calls --------------
 605 
 606   // Do a null check on the receiver as it would happen before the call to
 607   // callee (with all arguments still on the stack).
 608   Node* null_check_receiver_before_call(ciMethod* callee) {
 609     assert(!callee->is_static(), "must be a virtual method");
 610     const int nargs = callee->arg_size();
 611     inc_sp(nargs);
 612     Node* n = null_check_receiver();
 613     dec_sp(nargs);
 614     return n;
 615   }
 616 
 617   // Fill in argument edges for the call from argument(0), argument(1), ...
 618   // (The next step is to call set_edges_for_java_call.)
 619   void  set_arguments_for_java_call(CallJavaNode* call);
 620 
 621   // Fill in non-argument edges for the call.
 622   // Transform the call, and update the basics: control, i_o, memory.
 623   // (The next step is usually to call set_results_for_java_call.)
 624   void set_edges_for_java_call(CallJavaNode* call,
 625                                bool must_throw = false, bool separate_io_proj = false);
 626 
 627   // Finish up a java call that was started by set_edges_for_java_call.
 628   // Call add_exception on any throw arising from the call.
 629   // Return the call result (transformed).
 630   Node* set_results_for_java_call(CallJavaNode* call, bool separate_io_proj = false);
 631 
 632   // Similar to set_edges_for_java_call, but simplified for runtime calls.
 633   void  set_predefined_output_for_runtime_call(Node* call) {
 634     set_predefined_output_for_runtime_call(call, NULL, NULL);
 635   }
 636   void  set_predefined_output_for_runtime_call(Node* call,
 637                                                Node* keep_mem,
 638                                                const TypePtr* hook_mem);
 639   Node* set_predefined_input_for_runtime_call(SafePointNode* call);
 640 
 641   // Replace the call with the current state of the kit.  Requires
 642   // that the call was generated with separate io_projs so that
 643   // exceptional control flow can be handled properly.
 644   void replace_call(CallNode* call, Node* result);
 645 
 646   // helper functions for statistics
 647   void increment_counter(address counter_addr);   // increment a debug counter
 648   void increment_counter(Node*   counter_addr);   // increment a debug counter
 649 
 650   // Bail out to the interpreter right now
 651   // The optional klass is the one causing the trap.
 652   // The optional reason is debug information written to the compile log.
 653   // Optional must_throw is the same as with add_safepoint_edges.
 654   void uncommon_trap(int trap_request,
 655                      ciKlass* klass = NULL, const char* reason_string = NULL,
 656                      bool must_throw = false, bool keep_exact_action = false);
 657 
 658   // Shorthand, to avoid saying "Deoptimization::" so many times.
 659   void uncommon_trap(Deoptimization::DeoptReason reason,
 660                      Deoptimization::DeoptAction action,
 661                      ciKlass* klass = NULL, const char* reason_string = NULL,
 662                      bool must_throw = false, bool keep_exact_action = false) {
 663     uncommon_trap(Deoptimization::make_trap_request(reason, action),
 664                   klass, reason_string, must_throw, keep_exact_action);
 665   }
 666 
 667   // SP when bytecode needs to be reexecuted.
 668   virtual int reexecute_sp() { return sp(); }
 669 
 670   // Report if there were too many traps at the current method and bci.
 671   // Report if a trap was recorded, and/or PerMethodTrapLimit was exceeded.
 672   // If there is no MDO at all, report no trap unless told to assume it.
 673   bool too_many_traps(Deoptimization::DeoptReason reason) {
 674     return C->too_many_traps(method(), bci(), reason);
 675   }
 676 
 677   // Report if there were too many recompiles at the current method and bci.
 678   bool too_many_recompiles(Deoptimization::DeoptReason reason) {
 679     return C->too_many_recompiles(method(), bci(), reason);
 680   }
 681 
 682   // Returns the object (if any) which was created the moment before.
 683   Node* just_allocated_object(Node* current_control);
 684 
 685   static bool use_ReduceInitialCardMarks() {
 686     return (ReduceInitialCardMarks
 687             && Universe::heap()->can_elide_tlab_store_barriers());
 688   }
 689 
 690   // Sync Ideal and Graph kits.
 691   void sync_kit(IdealKit& ideal);
 692   void final_sync(IdealKit& ideal);
 693 
 694   // vanilla/CMS post barrier
 695   void write_barrier_post(Node *store, Node* obj,
 696                           Node* adr,  uint adr_idx, Node* val, bool use_precise);
 697 
 698   // G1 pre/post barriers
 699   void g1_write_barrier_pre(bool do_load,
 700                             Node* obj,
 701                             Node* adr,
 702                             uint alias_idx,
 703                             Node* val,
 704                             const TypeOopPtr* val_type,
 705                             Node* pre_val,
 706                             BasicType bt);
 707 
 708   void g1_write_barrier_post(Node* store,
 709                              Node* obj,
 710                              Node* adr,
 711                              uint alias_idx,
 712                              Node* val,
 713                              BasicType bt,
 714                              bool use_precise);
 715   // Helper function for g1
 716   private:
 717   void g1_mark_card(IdealKit& ideal, Node* card_adr, Node* store, uint oop_alias_idx,
 718                     Node* index, Node* index_adr,
 719                     Node* buffer, const TypeFunc* tf);
 720 
 721   public:
 722   // Helper function to round double arguments before a call
 723   void round_double_arguments(ciMethod* dest_method);
 724   void round_double_result(ciMethod* dest_method);
 725 
 726   // rounding for strict float precision conformance
 727   Node* precision_rounding(Node* n);
 728 
 729   // rounding for strict double precision conformance
 730   Node* dprecision_rounding(Node* n);
 731 
 732   // rounding for non-strict double stores
 733   Node* dstore_rounding(Node* n);
 734 
 735   // Helper functions for fast/slow path codes
 736   Node* opt_iff(Node* region, Node* iff);
 737   Node* make_runtime_call(int flags,
 738                           const TypeFunc* call_type, address call_addr,
 739                           const char* call_name,
 740                           const TypePtr* adr_type, // NULL if no memory effects
 741                           Node* parm0 = NULL, Node* parm1 = NULL,
 742                           Node* parm2 = NULL, Node* parm3 = NULL,
 743                           Node* parm4 = NULL, Node* parm5 = NULL,
 744                           Node* parm6 = NULL, Node* parm7 = NULL);
 745   enum {  // flag values for make_runtime_call
 746     RC_NO_FP = 1,               // CallLeafNoFPNode
 747     RC_NO_IO = 2,               // do not hook IO edges
 748     RC_NO_LEAF = 4,             // CallStaticJavaNode
 749     RC_MUST_THROW = 8,          // flag passed to add_safepoint_edges
 750     RC_NARROW_MEM = 16,         // input memory is same as output
 751     RC_UNCOMMON = 32,           // freq. expected to be like uncommon trap
 752     RC_LEAF = 0                 // null value:  no flags set
 753   };
 754 
 755   // merge in all memory slices from new_mem, along the given path
 756   void merge_memory(Node* new_mem, Node* region, int new_path);
 757   void make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj);
 758 
 759   // Helper functions to build synchronizations
 760   int next_monitor();
 761   Node* insert_mem_bar(int opcode, Node* precedent = NULL);
 762   Node* insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent = NULL);
 763   // Optional 'precedent' is appended as an extra edge, to force ordering.
 764   FastLockNode* shared_lock(Node* obj);
 765   void shared_unlock(Node* box, Node* obj);
 766 
 767   // helper functions for the fast path/slow path idioms
 768   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);
 769 
 770   // Generate an instance-of idiom.  Used by both the instance-of bytecode
 771   // and the reflective instance-of call.
 772   Node* gen_instanceof( Node *subobj, Node* superkls );
 773 
 774   // Generate a check-cast idiom.  Used by both the check-cast bytecode
 775   // and the array-store bytecode
 776   Node* gen_checkcast( Node *subobj, Node* superkls,
 777                        Node* *failure_control = NULL );
 778 
 779   // Generate a subtyping check.  Takes as input the subtype and supertype.
 780   // Returns 2 values: sets the default control() to the true path and
 781   // returns the false path.  Only reads from constant memory taken from the
 782   // default memory; does not write anything.  It also doesn't take in an
 783   // Object; if you wish to check an Object you need to load the Object's
 784   // class prior to coming here.
 785   Node* gen_subtype_check(Node* subklass, Node* superklass);
 786 
 787   // Static parse-time type checking logic for gen_subtype_check:
 788   enum { SSC_always_false, SSC_always_true, SSC_easy_test, SSC_full_test };
 789   int static_subtype_check(ciKlass* superk, ciKlass* subk);
 790 
 791   // Exact type check used for predicted calls and casts.
 792   // Rewrites (*casted_receiver) to be casted to the stronger type.
 793   // (Caller is responsible for doing replace_in_map.)
 794   Node* type_check_receiver(Node* receiver, ciKlass* klass, float prob,
 795                             Node* *casted_receiver);
 796 
 797   // implementation of object creation
 798   Node* set_output_for_allocation(AllocateNode* alloc,
 799                                   const TypeOopPtr* oop_type);
 800   Node* get_layout_helper(Node* klass_node, jint& constant_value);
 801   Node* new_instance(Node* klass_node,
 802                      Node* slow_test = NULL,
 803                      Node* *return_size_val = NULL);
 804   Node* new_array(Node* klass_node, Node* count_val, int nargs,
 805                   Node* *return_size_val = NULL);
 806 
 807   // java.lang.String helpers
 808   Node* load_String_offset(Node* ctrl, Node* str);
 809   Node* load_String_length(Node* ctrl, Node* str);
 810   Node* load_String_value(Node* ctrl, Node* str);
 811   void store_String_offset(Node* ctrl, Node* str, Node* value);
 812   void store_String_length(Node* ctrl, Node* str, Node* value);
 813   void store_String_value(Node* ctrl, Node* str, Node* value);
 814 
 815   // Handy for making control flow
 816   IfNode* create_and_map_if(Node* ctrl, Node* tst, float prob, float cnt) {
 817     IfNode* iff = new (C) IfNode(ctrl, tst, prob, cnt);// New IfNode's
 818     _gvn.set_type(iff, iff->Value(&_gvn)); // Value may be known at parse-time
 819     // Place 'if' on worklist if it will be in graph
 820     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
 821     return iff;
 822   }
 823 
 824   IfNode* create_and_xform_if(Node* ctrl, Node* tst, float prob, float cnt) {
 825     IfNode* iff = new (C) IfNode(ctrl, tst, prob, cnt);// New IfNode's
 826     _gvn.transform(iff);                           // Value may be known at parse-time
 827     // Place 'if' on worklist if it will be in graph
 828     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
 829     return iff;
 830   }
 831 
 832   // Insert a loop predicate into the graph
 833   void add_predicate(int nargs = 0);
 834   void add_predicate_impl(Deoptimization::DeoptReason reason, int nargs);
 835 };
 836 
 837 // Helper class to support building of control flow branches. Upon
 838 // creation the map and sp at bci are cloned and restored upon de-
 839 // struction. Typical use:
 840 //
 841 // { PreserveJVMState pjvms(this);
 842 //   // code of new branch
 843 // }
 844 // // here the JVM state at bci is established
 845 
 846 class PreserveJVMState: public StackObj {
 847  protected:
 848   GraphKit*      _kit;
 849 #ifdef ASSERT
 850   int            _block;  // PO of current block, if a Parse
 851   int            _bci;
 852 #endif
 853   SafePointNode* _map;
 854   uint           _sp;
 855 
 856  public:
 857   PreserveJVMState(GraphKit* kit, bool clone_map = true);
 858   ~PreserveJVMState();
 859 };
 860 
 861 // Helper class to build cutouts of the form if (p) ; else {x...}.
 862 // The code {x...} must not fall through.
 863 // The kit's main flow of control is set to the "then" continuation of if(p).
 864 class BuildCutout: public PreserveJVMState {
 865  public:
 866   BuildCutout(GraphKit* kit, Node* p, float prob, float cnt = COUNT_UNKNOWN);
 867   ~BuildCutout();
 868 };
 869 
 870 // Helper class to preserve the original _reexecute bit and _sp and restore
 871 // them back
 872 class PreserveReexecuteState: public StackObj {
 873  protected:
 874   GraphKit*                 _kit;
 875   uint                      _sp;
 876   JVMState::ReexecuteState  _reexecute;
 877 
 878  public:
 879   PreserveReexecuteState(GraphKit* kit);
 880   ~PreserveReexecuteState();
 881 };
 882 
 883 #endif // SHARE_VM_OPTO_GRAPHKIT_HPP