1 /*
  2  * Copyright (c) 2001, 2021, 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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 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/inlinetypenode.hpp"
 37 #include "opto/mulnode.hpp"
 38 #include "opto/phaseX.hpp"
 39 #include "opto/subnode.hpp"
 40 #include "opto/type.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* integercon(jlong con, BasicType bt)   const {
116     if (bt == T_INT) {
117       return intcon(checked_cast<jint>(con));
118     }
119     assert(bt == T_LONG, "basic type not an int or long");
120     return longcon(con);
121   }
122   Node* makecon(const Type *t)  const { return _gvn.makecon(t); }
123   Node* zerocon(BasicType bt)   const { return _gvn.zerocon(bt); }
124   // (See also macro MakeConX in type.hpp, which uses intcon or longcon.)
125 
126   jint  find_int_con(Node* n, jint value_if_unknown) {
127     return _gvn.find_int_con(n, value_if_unknown);
128   }
129   jlong find_long_con(Node* n, jlong value_if_unknown) {
130     return _gvn.find_long_con(n, value_if_unknown);
131   }
132   // (See also macro find_intptr_t_con in type.hpp, which uses one of these.)
133 
134   // JVM State accessors:
135   // Parser mapping from JVM indices into Nodes.
136   // Low slots are accessed by the StartNode::enum.
137   // Then come the locals at StartNode::Parms to StartNode::Parms+max_locals();
138   // Then come JVM stack slots.
139   // Finally come the monitors, if any.
140   // See layout accessors in class JVMState.
141 
142   SafePointNode*     map()      const { return _map; }
143   bool               has_exceptions() const { return _exceptions != NULL; }
144   JVMState*          jvms()     const { return map_not_null()->_jvms; }
145   int                sp()       const { return _sp; }
146   int                bci()      const { return _bci; }
147   Bytecodes::Code    java_bc()  const;
148   ciMethod*          method()   const { return _method; }
149 
150   void set_jvms(JVMState* jvms)       { set_map(jvms->map());
151                                         assert(jvms == this->jvms(), "sanity");
152                                         _sp = jvms->sp();
153                                         _bci = jvms->bci();
154                                         _method = jvms->has_method() ? jvms->method() : NULL; }
155   void set_map(SafePointNode* m)      { _map = m; debug_only(verify_map()); }
156   void set_sp(int sp)                 { assert(sp >= 0, "sp must be non-negative: %d", sp); _sp = sp; }
157   void clean_stack(int from_sp); // clear garbage beyond from_sp to top
158 
159   void inc_sp(int i)                  { set_sp(sp() + i); }
160   void dec_sp(int i)                  { set_sp(sp() - i); }
161   void set_bci(int bci)               { _bci = bci; }
162 
163   // Make sure jvms has current bci & sp.
164   JVMState* sync_jvms() const;
165   JVMState* sync_jvms_for_reexecute();
166 
167 #ifdef ASSERT
168   // Make sure JVMS has an updated copy of bci and sp.
169   // Also sanity-check method, depth, and monitor depth.
170   bool jvms_in_sync() const;
171 
172   // Make sure the map looks OK.
173   void verify_map() const;
174 
175   // Make sure a proposed exception state looks OK.
176   static void verify_exception_state(SafePointNode* ex_map);
177 #endif
178 
179   // Clone the existing map state.  (Implements PreserveJVMState.)
180   SafePointNode* clone_map();
181 
182   // Set the map to a clone of the given one.
183   void set_map_clone(SafePointNode* m);
184 
185   // Tell if the compilation is failing.
186   bool failing() const { return C->failing(); }
187 
188   // Set _map to NULL, signalling a stop to further bytecode execution.
189   // Preserve the map intact for future use, and return it back to the caller.
190   SafePointNode* stop() { SafePointNode* m = map(); set_map(NULL); return m; }
191 
192   // Stop, but first smash the map's inputs to NULL, to mark it dead.
193   void stop_and_kill_map();
194 
195   // Tell if _map is NULL, or control is top.
196   bool stopped();
197 
198   // Tell if this method or any caller method has exception handlers.
199   bool has_ex_handler();
200 
201   // Save an exception without blowing stack contents or other JVM state.
202   // (The extra pointer is stuck with add_req on the map, beyond the JVMS.)
203   static void set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop);
204 
205   // Recover a saved exception from its map.
206   static Node* saved_ex_oop(SafePointNode* ex_map);
207 
208   // Recover a saved exception from its map, and remove it from the map.
209   static Node* clear_saved_ex_oop(SafePointNode* ex_map);
210 
211 #ifdef ASSERT
212   // Recover a saved exception from its map, and remove it from the map.
213   static bool has_saved_ex_oop(SafePointNode* ex_map);
214 #endif
215 
216   // Push an exception in the canonical position for handlers (stack(0)).
217   void push_ex_oop(Node* ex_oop) {
218     ensure_stack(1);  // ensure room to push the exception
219     set_stack(0, ex_oop);
220     set_sp(1);
221     clean_stack(1);
222   }
223 
224   // Detach and return an exception state.
225   SafePointNode* pop_exception_state() {
226     SafePointNode* ex_map = _exceptions;
227     if (ex_map != NULL) {
228       _exceptions = ex_map->next_exception();
229       ex_map->set_next_exception(NULL);
230       debug_only(verify_exception_state(ex_map));
231     }
232     return ex_map;
233   }
234 
235   // Add an exception, using the given JVM state, without commoning.
236   void push_exception_state(SafePointNode* ex_map) {
237     debug_only(verify_exception_state(ex_map));
238     ex_map->set_next_exception(_exceptions);
239     _exceptions = ex_map;
240   }
241 
242   // Turn the current JVM state into an exception state, appending the ex_oop.
243   SafePointNode* make_exception_state(Node* ex_oop);
244 
245   // Add an exception, using the given JVM state.
246   // Combine all exceptions with a common exception type into a single state.
247   // (This is done via combine_exception_states.)
248   void add_exception_state(SafePointNode* ex_map);
249 
250   // Combine all exceptions of any sort whatever into a single master state.
251   SafePointNode* combine_and_pop_all_exception_states() {
252     if (_exceptions == NULL)  return NULL;
253     SafePointNode* phi_map = pop_exception_state();
254     SafePointNode* ex_map;
255     while ((ex_map = pop_exception_state()) != NULL) {
256       combine_exception_states(ex_map, phi_map);
257     }
258     return phi_map;
259   }
260 
261   // Combine the two exception states, building phis as necessary.
262   // The second argument is updated to include contributions from the first.
263   void combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map);
264 
265   // Reset the map to the given state.  If there are any half-finished phis
266   // in it (created by combine_exception_states), transform them now.
267   // Returns the exception oop.  (Caller must call push_ex_oop if required.)
268   Node* use_exception_state(SafePointNode* ex_map);
269 
270   // Collect exceptions from a given JVM state into my exception list.
271   void add_exception_states_from(JVMState* jvms);
272 
273   // Collect all raised exceptions into the current JVM state.
274   // Clear the current exception list and map, returns the combined states.
275   JVMState* transfer_exceptions_into_jvms();
276 
277   // Helper to throw a built-in exception.
278   // Range checks take the offending index.
279   // Cast and array store checks take the offending class.
280   // Others do not take the optional argument.
281   // The JVMS must allow the bytecode to be re-executed
282   // via an uncommon trap.
283   void builtin_throw(Deoptimization::DeoptReason reason, Node* arg = NULL);
284 
285   // Helper to check the JavaThread::_should_post_on_exceptions flag
286   // and branch to an uncommon_trap if it is true (with the specified reason and must_throw)
287   void uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
288                                                   bool must_throw) ;
289 
290   // Helper Functions for adding debug information
291   void kill_dead_locals();
292 #ifdef ASSERT
293   bool dead_locals_are_killed();
294 #endif
295   // The call may deoptimize.  Supply required JVM state as debug info.
296   // If must_throw is true, the call is guaranteed not to return normally.
297   void add_safepoint_edges(SafePointNode* call,
298                            bool must_throw = false);
299 
300   // How many stack inputs does the current BC consume?
301   // And, how does the stack change after the bytecode?
302   // Returns false if unknown.
303   bool compute_stack_effects(int& inputs, int& depth);
304 
305   // Add a fixed offset to a pointer
306   Node* basic_plus_adr(Node* base, Node* ptr, intptr_t offset) {
307     return basic_plus_adr(base, ptr, MakeConX(offset));
308   }
309   Node* basic_plus_adr(Node* base, intptr_t offset) {
310     return basic_plus_adr(base, base, MakeConX(offset));
311   }
312   // Add a variable offset to a pointer
313   Node* basic_plus_adr(Node* base, Node* offset) {
314     return basic_plus_adr(base, base, offset);
315   }
316   Node* basic_plus_adr(Node* base, Node* ptr, Node* offset);
317 
318 
319   // Some convenient shortcuts for common nodes
320   Node* IfTrue(IfNode* iff)                   { return _gvn.transform(new IfTrueNode(iff));      }
321   Node* IfFalse(IfNode* iff)                  { return _gvn.transform(new IfFalseNode(iff));     }
322 
323   Node* AddI(Node* l, Node* r)                { return _gvn.transform(new AddINode(l, r));       }
324   Node* SubI(Node* l, Node* r)                { return _gvn.transform(new SubINode(l, r));       }
325   Node* MulI(Node* l, Node* r)                { return _gvn.transform(new MulINode(l, r));       }
326   Node* DivI(Node* ctl, Node* l, Node* r)     { return _gvn.transform(new DivINode(ctl, l, r));  }
327 
328   Node* AndI(Node* l, Node* r)                { return _gvn.transform(new AndINode(l, r));       }
329   Node* OrI(Node* l, Node* r)                 { return _gvn.transform(new OrINode(l, r));        }
330   Node* XorI(Node* l, Node* r)                { return _gvn.transform(new XorINode(l, r));       }
331 
332   Node* MaxI(Node* l, Node* r)                { return _gvn.transform(new MaxINode(l, r));       }
333   Node* MinI(Node* l, Node* r)                { return _gvn.transform(new MinINode(l, r));       }
334 
335   Node* LShiftI(Node* l, Node* r)             { return _gvn.transform(new LShiftINode(l, r));    }
336   Node* RShiftI(Node* l, Node* r)             { return _gvn.transform(new RShiftINode(l, r));    }
337   Node* URShiftI(Node* l, Node* r)            { return _gvn.transform(new URShiftINode(l, r));   }
338 
339   Node* CmpI(Node* l, Node* r)                { return _gvn.transform(new CmpINode(l, r));       }
340   Node* CmpL(Node* l, Node* r)                { return _gvn.transform(new CmpLNode(l, r));       }
341   Node* CmpP(Node* l, Node* r)                { return _gvn.transform(new CmpPNode(l, r));       }
342   Node* Bool(Node* cmp, BoolTest::mask relop) { return _gvn.transform(new BoolNode(cmp, relop)); }
343 
344   Node* AddP(Node* b, Node* a, Node* o)       { return _gvn.transform(new AddPNode(b, a, o));    }
345 
346   // Convert between int and long, and size_t.
347   // (See macros ConvI2X, etc., in type.hpp for ConvI2X, etc.)
348   Node* ConvI2L(Node* offset);
349   Node* ConvI2UL(Node* offset);
350   Node* ConvL2I(Node* offset);
351   // Find out the klass of an object.
352   Node* load_object_klass(Node* object);
353   // Find out the length of an array.
354   Node* load_array_length(Node* array);
355   // Cast array allocation's length as narrow as possible.
356   // If replace_length_in_map is true, replace length with CastIINode in map.
357   // This method is invoked after creating/moving ArrayAllocationNode or in load_array_length
358   Node* array_ideal_length(AllocateArrayNode* alloc,
359                            const TypeOopPtr* oop_type,
360                            bool replace_length_in_map);
361 
362 
363   // Helper function to do a NULL pointer check or ZERO check based on type.
364   // Throw an exception if a given value is null.
365   // Return the value cast to not-null.
366   // Be clever about equivalent dominating null checks.
367   Node* null_check_common(Node* value, BasicType type,
368                           bool assert_null = false,
369                           Node* *null_control = NULL,
370                           bool speculative = false,
371                           bool is_init_check = false);
372   Node* null_check(Node* value, BasicType type = T_OBJECT) {
373     return null_check_common(value, type, false, NULL, !_gvn.type(value)->speculative_maybe_null());
374   }
375   Node* null_check_receiver() {
376     assert(argument(0)->bottom_type()->isa_ptr(), "must be");
377     return null_check(argument(0));
378   }
379   Node* zero_check_int(Node* value) {
380     assert(value->bottom_type()->basic_type() == T_INT,
381            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
382     return null_check_common(value, T_INT);
383   }
384   Node* zero_check_long(Node* value) {
385     assert(value->bottom_type()->basic_type() == T_LONG,
386            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
387     return null_check_common(value, T_LONG);
388   }
389   // Throw an uncommon trap if a given value is __not__ null.
390   // Return the value cast to null, and be clever about dominating checks.
391   Node* null_assert(Node* value, BasicType type = T_OBJECT) {
392     return null_check_common(value, type, true, NULL, _gvn.type(value)->speculative_always_null());
393   }
394 
395   // Check if value is null and abort if it is
396   Node* must_be_not_null(Node* value, bool do_replace_in_map);
397 
398   // Null check oop.  Return null-path control into (*null_control).
399   // Return a cast-not-null node which depends on the not-null control.
400   // If never_see_null, use an uncommon trap (*null_control sees a top).
401   // The cast is not valid along the null path; keep a copy of the original.
402   // If safe_for_replace, then we can replace the value with the cast
403   // in the parsing map (the cast is guaranteed to dominate the map)
404   Node* null_check_oop(Node* value, Node* *null_control,
405                        bool never_see_null = false,
406                        bool safe_for_replace = false,
407                        bool speculative = false);
408 
409   // Check the null_seen bit.
410   bool seems_never_null(Node* obj, ciProfileData* data, bool& speculating);
411 
412   void guard_klass_being_initialized(Node* klass);
413   void guard_init_thread(Node* klass);
414 
415   void clinit_barrier(ciInstanceKlass* ik, ciMethod* context);
416 
417   // Check for unique class for receiver at call
418   ciKlass* profile_has_unique_klass() {
419     ciCallProfile profile = method()->call_profile_at_bci(bci());
420     if (profile.count() >= 0 &&         // no cast failures here
421         profile.has_receiver(0) &&
422         profile.morphism() == 1) {
423       return profile.receiver(0);
424     }
425     return NULL;
426   }
427 
428   // record type from profiling with the type system
429   Node* record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind);
430   void record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc);
431   void record_profiled_parameters_for_speculation();
432   void record_profiled_return_for_speculation();
433   Node* record_profiled_receiver_for_speculation(Node* n);
434 
435   // Use the type profile to narrow an object type.
436   Node* maybe_cast_profiled_receiver(Node* not_null_obj,
437                                      ciKlass* require_klass,
438                                      ciKlass* spec,
439                                      bool safe_for_replace);
440 
441   // Cast obj to type and emit guard unless we had too many traps here already
442   Node* maybe_cast_profiled_obj(Node* obj,
443                                 ciKlass* type,
444                                 bool not_null = false);
445 
446   // Cast obj to not-null on this path
447   Node* cast_not_null(Node* obj, bool do_replace_in_map = true);
448   // Replace all occurrences of one node by another.
449   void replace_in_map(Node* old, Node* neww);
450 
451   void  push(Node* n)     { map_not_null();        _map->set_stack(_map->_jvms,   _sp++        , n); }
452   Node* pop()             { map_not_null(); return _map->stack(    _map->_jvms, --_sp             ); }
453   Node* peek(int off = 0) { map_not_null(); return _map->stack(    _map->_jvms,   _sp - off - 1   ); }
454 
455   void push_pair(Node* ldval) {
456     push(ldval);
457     push(top());  // the halfword is merely a placeholder
458   }
459   void push_pair_local(int i) {
460     // longs are stored in locals in "push" order
461     push(  local(i+0) );  // the real value
462     assert(local(i+1) == top(), "");
463     push(top());  // halfword placeholder
464   }
465   Node* pop_pair() {
466     // the second half is pushed last & popped first; it contains exactly nothing
467     Node* halfword = pop();
468     assert(halfword == top(), "");
469     // the long bits are pushed first & popped last:
470     return pop();
471   }
472   void set_pair_local(int i, Node* lval) {
473     // longs are stored in locals as a value/half pair (like doubles)
474     set_local(i+0, lval);
475     set_local(i+1, top());
476   }
477 
478   // Push the node, which may be zero, one, or two words.
479   void push_node(BasicType n_type, Node* n) {
480     int n_size = type2size[n_type];
481     if      (n_size == 1)  push(      n );  // T_INT, ...
482     else if (n_size == 2)  push_pair( n );  // T_DOUBLE, T_LONG
483     else                   { assert(n_size == 0, "must be T_VOID"); }
484   }
485 
486   Node* pop_node(BasicType n_type) {
487     int n_size = type2size[n_type];
488     if      (n_size == 1)  return pop();
489     else if (n_size == 2)  return pop_pair();
490     else                   return NULL;
491   }
492 
493   Node* control()               const { return map_not_null()->control(); }
494   Node* i_o()                   const { return map_not_null()->i_o(); }
495   Node* returnadr()             const { return map_not_null()->returnadr(); }
496   Node* frameptr()              const { return map_not_null()->frameptr(); }
497   Node* local(uint idx)         const { map_not_null(); return _map->local(      _map->_jvms, idx); }
498   Node* stack(uint idx)         const { map_not_null(); return _map->stack(      _map->_jvms, idx); }
499   Node* argument(uint idx)      const { map_not_null(); return _map->argument(   _map->_jvms, idx); }
500   Node* monitor_box(uint idx)   const { map_not_null(); return _map->monitor_box(_map->_jvms, idx); }
501   Node* monitor_obj(uint idx)   const { map_not_null(); return _map->monitor_obj(_map->_jvms, idx); }
502 
503   void set_control  (Node* c)         { map_not_null()->set_control(c); }
504   void set_i_o      (Node* c)         { map_not_null()->set_i_o(c); }
505   void set_local(uint idx, Node* c)   { map_not_null(); _map->set_local(   _map->_jvms, idx, c); }
506   void set_stack(uint idx, Node* c)   { map_not_null(); _map->set_stack(   _map->_jvms, idx, c); }
507   void set_argument(uint idx, Node* c){ map_not_null(); _map->set_argument(_map->_jvms, idx, c); }
508   void ensure_stack(uint stk_size)    { map_not_null(); _map->ensure_stack(_map->_jvms, stk_size); }
509 
510   // Access unaliased memory
511   Node* memory(uint alias_idx);
512   Node* memory(const TypePtr *tp) { return memory(C->get_alias_index(tp)); }
513   Node* memory(Node* adr) { return memory(_gvn.type(adr)->is_ptr()); }
514 
515   // Access immutable memory
516   Node* immutable_memory() { return C->immutable_memory(); }
517 
518   // Set unaliased memory
519   void set_memory(Node* c, uint alias_idx) { merged_memory()->set_memory_at(alias_idx, c); }
520   void set_memory(Node* c, const TypePtr *tp) { set_memory(c,C->get_alias_index(tp)); }
521   void set_memory(Node* c, Node* adr) { set_memory(c,_gvn.type(adr)->is_ptr()); }
522 
523   // Get the entire memory state (probably a MergeMemNode), and reset it
524   // (The resetting prevents somebody from using the dangling Node pointer.)
525   Node* reset_memory();
526 
527   // Get the entire memory state, asserted to be a MergeMemNode.
528   MergeMemNode* merged_memory() {
529     Node* mem = map_not_null()->memory();
530     assert(mem->is_MergeMem(), "parse memory is always pre-split");
531     return mem->as_MergeMem();
532   }
533 
534   // Set the entire memory state; produce a new MergeMemNode.
535   void set_all_memory(Node* newmem);
536 
537   // Create a memory projection from the call, then set_all_memory.
538   void set_all_memory_call(Node* call, bool separate_io_proj = false);
539 
540   // Create a LoadNode, reading from the parser's memory state.
541   // (Note:  require_atomic_access is useful only with T_LONG.)
542   //
543   // We choose the unordered semantics by default because we have
544   // adapted the `do_put_xxx' and `do_get_xxx' procedures for the case
545   // of volatile fields.
546   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
547                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
548                   bool require_atomic_access = false, bool unaligned = false,
549                   bool mismatched = false, bool unsafe = false, uint8_t barrier_data = 0) {
550     // This version computes alias_index from bottom_type
551     return make_load(ctl, adr, t, bt, adr->bottom_type()->is_ptr(),
552                      mo, control_dependency, require_atomic_access,
553                      unaligned, mismatched, unsafe, barrier_data);
554   }
555   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, const TypePtr* adr_type,
556                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
557                   bool require_atomic_access = false, bool unaligned = false,
558                   bool mismatched = false, bool unsafe = false, uint8_t barrier_data = 0) {
559     // This version computes alias_index from an address type
560     assert(adr_type != NULL, "use other make_load factory");
561     return make_load(ctl, adr, t, bt, C->get_alias_index(adr_type),
562                      mo, control_dependency, require_atomic_access,
563                      unaligned, mismatched, unsafe, barrier_data);
564   }
565   // This is the base version which is given an alias index.
566   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, int adr_idx,
567                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
568                   bool require_atomic_access = false, bool unaligned = false,
569                   bool mismatched = false, bool unsafe = false, uint8_t barrier_data = 0);
570 
571   // Create & transform a StoreNode and store the effect into the
572   // parser's memory state.
573   //
574   // We must ensure that stores of object references will be visible
575   // only after the object's initialization. So the clients of this
576   // procedure must indicate that the store requires `release'
577   // semantics, if the stored value is an object reference that might
578   // point to a new object and may become externally visible.
579   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
580                         const TypePtr* adr_type,
581                         MemNode::MemOrd mo,
582                         bool require_atomic_access = false,
583                         bool unaligned = false,
584                         bool mismatched = false,
585                         bool unsafe = false) {
586     // This version computes alias_index from an address type
587     assert(adr_type != NULL, "use other store_to_memory factory");
588     return store_to_memory(ctl, adr, val, bt,
589                            C->get_alias_index(adr_type),
590                            mo, require_atomic_access,
591                            unaligned, mismatched, unsafe);
592   }
593   // This is the base version which is given alias index
594   // Return the new StoreXNode
595   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
596                         int adr_idx,
597                         MemNode::MemOrd,
598                         bool require_atomic_access = false,
599                         bool unaligned = false,
600                         bool mismatched = false,
601                         bool unsafe = false);
602 
603   // Perform decorated accesses
604 
605   Node* access_store_at(Node* obj,   // containing obj
606                         Node* adr,   // actual adress to store val at
607                         const TypePtr* adr_type,
608                         Node* val,
609                         const Type* val_type,
610                         BasicType bt,
611                         DecoratorSet decorators,
612                         bool safe_for_replace = true);
613 
614   Node* access_load_at(Node* obj,   // containing obj
615                        Node* adr,   // actual adress to load val at
616                        const TypePtr* adr_type,
617                        const Type* val_type,
618                        BasicType bt,
619                        DecoratorSet decorators,
620                        Node* ctl = NULL);
621 
622   Node* access_load(Node* adr,   // actual adress to load val at
623                     const Type* val_type,
624                     BasicType bt,
625                     DecoratorSet decorators);
626 
627   Node* access_atomic_cmpxchg_val_at(Node* obj,
628                                      Node* adr,
629                                      const TypePtr* adr_type,
630                                      int alias_idx,
631                                      Node* expected_val,
632                                      Node* new_val,
633                                      const Type* value_type,
634                                      BasicType bt,
635                                      DecoratorSet decorators);
636 
637   Node* access_atomic_cmpxchg_bool_at(Node* obj,
638                                       Node* adr,
639                                       const TypePtr* adr_type,
640                                       int alias_idx,
641                                       Node* expected_val,
642                                       Node* new_val,
643                                       const Type* value_type,
644                                       BasicType bt,
645                                       DecoratorSet decorators);
646 
647   Node* access_atomic_xchg_at(Node* obj,
648                               Node* adr,
649                               const TypePtr* adr_type,
650                               int alias_idx,
651                               Node* new_val,
652                               const Type* value_type,
653                               BasicType bt,
654                               DecoratorSet decorators);
655 
656   Node* access_atomic_add_at(Node* obj,
657                              Node* adr,
658                              const TypePtr* adr_type,
659                              int alias_idx,
660                              Node* new_val,
661                              const Type* value_type,
662                              BasicType bt,
663                              DecoratorSet decorators);
664 
665   void access_clone(Node* src, Node* dst, Node* size, bool is_array);
666 
667   // Return addressing for an array element.
668   Node* array_element_address(Node* ary, Node* idx, BasicType elembt,
669                               // Optional constraint on the array size:
670                               const TypeInt* sizetype = NULL,
671                               // Optional control dependency (for example, on range check)
672                               Node* ctrl = NULL);
673 
674   // Return a load of array element at idx.
675   Node* load_array_element(Node* ary, Node* idx, const TypeAryPtr* arytype, bool set_ctrl);
676 
677   //---------------- Dtrace support --------------------
678   void make_dtrace_method_entry_exit(ciMethod* method, bool is_entry);
679   void make_dtrace_method_entry(ciMethod* method) {
680     make_dtrace_method_entry_exit(method, true);
681   }
682   void make_dtrace_method_exit(ciMethod* method) {
683     make_dtrace_method_entry_exit(method, false);
684   }
685 
686   //--------------- stub generation -------------------
687  public:
688   void gen_stub(address C_function,
689                 const char *name,
690                 int is_fancy_jump,
691                 bool pass_tls,
692                 bool return_pc);
693 
694   //---------- help for generating calls --------------
695 
696   // Do a null check on the receiver as it would happen before the call to
697   // callee (with all arguments still on the stack).
698   Node* null_check_receiver_before_call(ciMethod* callee, bool replace_value = true) {
699     assert(!callee->is_static(), "must be a virtual method");
700     if (argument(0)->is_InlineType()) {
701       return argument(0);
702     }
703     // Callsite signature can be different from actual method being called (i.e _linkTo* sites).
704     // Use callsite signature always.
705     ciMethod* declared_method = method()->get_method_at_bci(bci());
706     const int nargs = declared_method->arg_size();
707     inc_sp(nargs);
708     Node* n = null_check_receiver();
709     // TODO Remove this code once InlineTypeNodes are replaced by InlineTypePtrNodes
710     set_argument(0, n);
711     dec_sp(nargs);
712     // Scalarize inline type receiver
713     const Type* recv_type = gvn().type(n);
714     if (recv_type->is_inlinetypeptr()) {
715       assert(!recv_type->maybe_null(), "should never be null");
716       Node* vt = InlineTypeNode::make_from_oop(this, n, recv_type->inline_klass());
717       set_argument(0, vt);
718       if (replace_value && is_Parse()) {
719         // Only replace in map if we are not incrementally inlining because we
720         // share a map with the caller which might expect the inline type as oop.
721         assert(!Compile::current()->inlining_incrementally(), "sanity");
722         replace_in_map(n, vt);
723       }
724       n = vt;
725     }
726     return n;
727   }
728 
729   // Fill in argument edges for the call from argument(0), argument(1), ...
730   // (The next step is to call set_edges_for_java_call.)
731   void  set_arguments_for_java_call(CallJavaNode* call, bool is_late_inline = false);
732 
733   // Fill in non-argument edges for the call.
734   // Transform the call, and update the basics: control, i_o, memory.
735   // (The next step is usually to call set_results_for_java_call.)
736   void set_edges_for_java_call(CallJavaNode* call,
737                                bool must_throw = false, bool separate_io_proj = false);
738 
739   // Finish up a java call that was started by set_edges_for_java_call.
740   // Call add_exception on any throw arising from the call.
741   // Return the call result (transformed).
742   Node* set_results_for_java_call(CallJavaNode* call, bool separate_io_proj = false, bool deoptimize = false);
743 
744   // Similar to set_edges_for_java_call, but simplified for runtime calls.
745   void  set_predefined_output_for_runtime_call(Node* call) {
746     set_predefined_output_for_runtime_call(call, NULL, NULL);
747   }
748   void  set_predefined_output_for_runtime_call(Node* call,
749                                                Node* keep_mem,
750                                                const TypePtr* hook_mem);
751   Node* set_predefined_input_for_runtime_call(SafePointNode* call, Node* narrow_mem = NULL);
752 
753   // Replace the call with the current state of the kit.  Requires
754   // that the call was generated with separate io_projs so that
755   // exceptional control flow can be handled properly.
756   void replace_call(CallNode* call, Node* result, bool do_replaced_nodes = false);
757 
758   // helper functions for statistics
759   void increment_counter(address counter_addr);   // increment a debug counter
760   void increment_counter(Node*   counter_addr);   // increment a debug counter
761 
762   // Bail out to the interpreter right now
763   // The optional klass is the one causing the trap.
764   // The optional reason is debug information written to the compile log.
765   // Optional must_throw is the same as with add_safepoint_edges.
766   void uncommon_trap(int trap_request,
767                      ciKlass* klass = NULL, const char* reason_string = NULL,
768                      bool must_throw = false, bool keep_exact_action = false);
769 
770   // Shorthand, to avoid saying "Deoptimization::" so many times.
771   void uncommon_trap(Deoptimization::DeoptReason reason,
772                      Deoptimization::DeoptAction action,
773                      ciKlass* klass = NULL, const char* reason_string = NULL,
774                      bool must_throw = false, bool keep_exact_action = false) {
775     uncommon_trap(Deoptimization::make_trap_request(reason, action),
776                   klass, reason_string, must_throw, keep_exact_action);
777   }
778 
779   // Bail out to the interpreter and keep exact action (avoid switching to Action_none).
780   void uncommon_trap_exact(Deoptimization::DeoptReason reason,
781                            Deoptimization::DeoptAction action,
782                            ciKlass* klass = NULL, const char* reason_string = NULL,
783                            bool must_throw = false) {
784     uncommon_trap(Deoptimization::make_trap_request(reason, action),
785                   klass, reason_string, must_throw, /*keep_exact_action=*/true);
786   }
787 
788   // SP when bytecode needs to be reexecuted.
789   virtual int reexecute_sp() { return sp(); }
790 
791   // Report if there were too many traps at the current method and bci.
792   // Report if a trap was recorded, and/or PerMethodTrapLimit was exceeded.
793   // If there is no MDO at all, report no trap unless told to assume it.
794   bool too_many_traps(Deoptimization::DeoptReason reason) {
795     return C->too_many_traps(method(), bci(), reason);
796   }
797 
798   // Report if there were too many recompiles at the current method and bci.
799   bool too_many_recompiles(Deoptimization::DeoptReason reason) {
800     return C->too_many_recompiles(method(), bci(), reason);
801   }
802 
803   bool too_many_traps_or_recompiles(Deoptimization::DeoptReason reason) {
804       return C->too_many_traps_or_recompiles(method(), bci(), reason);
805   }
806 
807   // Returns the object (if any) which was created the moment before.
808   Node* just_allocated_object(Node* current_control);
809 
810   // Sync Ideal and Graph kits.
811   void sync_kit(IdealKit& ideal);
812   void final_sync(IdealKit& ideal);
813 
814   public:
815   // Helper function to round double arguments before a call
816   void round_double_arguments(ciMethod* dest_method);
817 
818   // rounding for strict float precision conformance
819   Node* precision_rounding(Node* n);
820 
821   // rounding for strict double precision conformance
822   Node* dprecision_rounding(Node* n);
823 
824   // rounding for non-strict double stores
825   Node* dstore_rounding(Node* n);
826 
827   // Helper functions for fast/slow path codes
828   Node* opt_iff(Node* region, Node* iff);
829   Node* make_runtime_call(int flags,
830                           const TypeFunc* call_type, address call_addr,
831                           const char* call_name,
832                           const TypePtr* adr_type, // NULL if no memory effects
833                           Node* parm0 = NULL, Node* parm1 = NULL,
834                           Node* parm2 = NULL, Node* parm3 = NULL,
835                           Node* parm4 = NULL, Node* parm5 = NULL,
836                           Node* parm6 = NULL, Node* parm7 = NULL,
837                           Node* parm8 = NULL);
838 
839   Node* sign_extend_byte(Node* in);
840   Node* sign_extend_short(Node* in);
841 
842   Node* make_native_call(address call_addr, const TypeFunc* call_type, uint nargs, ciNativeEntryPoint* nep);
843 
844   enum {  // flag values for make_runtime_call
845     RC_NO_FP = 1,               // CallLeafNoFPNode
846     RC_NO_IO = 2,               // do not hook IO edges
847     RC_NO_LEAF = 4,             // CallStaticJavaNode
848     RC_MUST_THROW = 8,          // flag passed to add_safepoint_edges
849     RC_NARROW_MEM = 16,         // input memory is same as output
850     RC_UNCOMMON = 32,           // freq. expected to be like uncommon trap
851     RC_VECTOR = 64,             // CallLeafVectorNode
852     RC_LEAF = 0                 // null value:  no flags set
853   };
854 
855   // merge in all memory slices from new_mem, along the given path
856   void merge_memory(Node* new_mem, Node* region, int new_path);
857   void make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize = false);
858 
859   // Helper functions to build synchronizations
860   int next_monitor();
861   Node* insert_mem_bar(int opcode, Node* precedent = NULL);
862   Node* insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent = NULL);
863   // Optional 'precedent' is appended as an extra edge, to force ordering.
864   FastLockNode* shared_lock(Node* obj);
865   void shared_unlock(Node* box, Node* obj);
866 
867   // helper functions for the fast path/slow path idioms
868   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);
869 
870   // Generate an instance-of idiom.  Used by both the instance-of bytecode
871   // and the reflective instance-of call.
872   Node* gen_instanceof(Node *subobj, Node* superkls, bool safe_for_replace = false);
873 
874   // Generate a check-cast idiom.  Used by both the check-cast bytecode
875   // and the array-store bytecode
876   Node* gen_checkcast(Node *subobj, Node* superkls, Node* *failure_control = NULL, bool null_free = false);
877 
878   // Inline types
879   Node* inline_type_test(Node* obj, bool is_inline = true);
880   Node* is_val_mirror(Node* mirror);
881   Node* array_lh_test(Node* kls, jint mask, jint val, bool eq = true);
882   Node* flat_array_test(Node* ary, bool flat = true);
883   Node* null_free_array_test(Node* klass, bool null_free = true);
884   Node* inline_array_null_guard(Node* ary, Node* val, int nargs, bool safe_for_replace = false);
885 
886   Node* gen_subtype_check(Node* obj, Node* superklass);
887 
888   // Exact type check used for predicted calls and casts.
889   // Rewrites (*casted_receiver) to be casted to the stronger type.
890   // (Caller is responsible for doing replace_in_map.)
891   Node* type_check_receiver(Node* receiver, ciKlass* klass, float prob,
892                             Node* *casted_receiver);
893   Node* type_check(Node* recv_klass, const TypeKlassPtr* tklass, float prob);
894 
895   // Inexact type check used for predicted calls.
896   Node* subtype_check_receiver(Node* receiver, ciKlass* klass,
897                                Node** casted_receiver);
898 
899   // implementation of object creation
900   Node* set_output_for_allocation(AllocateNode* alloc,
901                                   const TypeOopPtr* oop_type,
902                                   bool deoptimize_on_exception=false);
903   Node* get_layout_helper(Node* klass_node, jint& constant_value);
904   Node* new_instance(Node* klass_node,
905                      Node* slow_test = NULL,
906                      Node* *return_size_val = NULL,
907                      bool deoptimize_on_exception = false,
908                      InlineTypeBaseNode* inline_type_node = NULL);
909   Node* new_array(Node* klass_node, Node* count_val, int nargs,
910                   Node* *return_size_val = NULL,
911                   bool deoptimize_on_exception = false);
912 
913   // java.lang.String helpers
914   Node* load_String_length(Node* str, bool set_ctrl);
915   Node* load_String_value(Node* str, bool set_ctrl);
916   Node* load_String_coder(Node* str, bool set_ctrl);
917   void store_String_value(Node* str, Node* value);
918   void store_String_coder(Node* str, Node* value);
919   Node* capture_memory(const TypePtr* src_type, const TypePtr* dst_type);
920   Node* compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count);
921   void inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count);
922   void inflate_string_slow(Node* src, Node* dst, Node* start, Node* count);
923 
924   // Handy for making control flow
925   IfNode* create_and_map_if(Node* ctrl, Node* tst, float prob, float cnt) {
926     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
927     _gvn.set_type(iff, iff->Value(&_gvn)); // Value may be known at parse-time
928     // Place 'if' on worklist if it will be in graph
929     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
930     return iff;
931   }
932 
933   IfNode* create_and_xform_if(Node* ctrl, Node* tst, float prob, float cnt) {
934     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
935     _gvn.transform(iff);                           // Value may be known at parse-time
936     // Place 'if' on worklist if it will be in graph
937     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
938     return iff;
939   }
940 
941   void add_empty_predicates(int nargs = 0);
942   void add_empty_predicate_impl(Deoptimization::DeoptReason reason, int nargs);
943 
944   Node* make_constant_from_field(ciField* field, Node* obj);
945   Node* load_mirror_from_klass(Node* klass);
946 
947   // Vector API support (implemented in vectorIntrinsics.cpp)
948   Node* box_vector(Node* in, const TypeInstPtr* vbox_type, BasicType elem_bt, int num_elem, bool deoptimize_on_exception = false);
949   Node* unbox_vector(Node* in, const TypeInstPtr* vbox_type, BasicType elem_bt, int num_elem, bool shuffle_to_vector = false);
950   Node* vector_shift_count(Node* cnt, int shift_op, BasicType bt, int num_elem);
951 };
952 
953 // Helper class to support building of control flow branches. Upon
954 // creation the map and sp at bci are cloned and restored upon de-
955 // struction. Typical use:
956 //
957 // { PreserveJVMState pjvms(this);
958 //   // code of new branch
959 // }
960 // // here the JVM state at bci is established
961 
962 class PreserveJVMState: public StackObj {
963  protected:
964   GraphKit*      _kit;
965 #ifdef ASSERT
966   int            _block;  // PO of current block, if a Parse
967   int            _bci;
968 #endif
969   SafePointNode* _map;
970   uint           _sp;
971 
972  public:
973   PreserveJVMState(GraphKit* kit, bool clone_map = true);
974   ~PreserveJVMState();
975 };
976 
977 // Helper class to build cutouts of the form if (p) ; else {x...}.
978 // The code {x...} must not fall through.
979 // The kit's main flow of control is set to the "then" continuation of if(p).
980 class BuildCutout: public PreserveJVMState {
981  public:
982   BuildCutout(GraphKit* kit, Node* p, float prob, float cnt = COUNT_UNKNOWN);
983   ~BuildCutout();
984 };
985 
986 // Helper class to preserve the original _reexecute bit and _sp and restore
987 // them back
988 class PreserveReexecuteState: public StackObj {
989  protected:
990   GraphKit*                 _kit;
991   uint                      _sp;
992   JVMState::ReexecuteState  _reexecute;
993 
994  public:
995   PreserveReexecuteState(GraphKit* kit);
996   ~PreserveReexecuteState();
997 };
998 
999 #endif // SHARE_OPTO_GRAPHKIT_HPP