1 /*
  2  * Copyright (c) 2001, 2026, 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
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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/mulnode.hpp"
 37 #include "opto/phaseX.hpp"
 38 #include "opto/subnode.hpp"
 39 #include "opto/type.hpp"
 40 #include "runtime/deoptimization.hpp"
 41 
 42 class BarrierSetC2;
 43 class FastLockNode;
 44 class FastUnlockNode;
 45 class IdealKit;
 46 class LibraryCallKit;
 47 class Parse;
 48 class RootNode;
 49 
 50 //-----------------------------------------------------------------------------
 51 //----------------------------GraphKit-----------------------------------------
 52 // Toolkit for building the common sorts of subgraphs.
 53 // Does not know about bytecode parsing or type-flow results.
 54 // It is able to create graphs implementing the semantics of most
 55 // or all bytecodes, so that it can expand intrinsics and calls.
 56 // It may depend on JVMState structure, but it must not depend
 57 // on specific bytecode streams.
 58 class GraphKit : public Phase {
 59   friend class PreserveJVMState;
 60 
 61  protected:
 62   ciEnv*            _env;       // Compilation environment
 63   PhaseGVN         &_gvn;       // Some optimizations while parsing
 64   SafePointNode*    _map;       // Parser map from JVM to Nodes
 65   SafePointNode*    _exceptions;// Parser map(s) for exception state(s)
 66   int               _bci;       // JVM Bytecode Pointer
 67   ciMethod*         _method;    // JVM Current Method
 68   BarrierSetC2*     _barrier_set;
 69 
 70  private:
 71   int               _sp;        // JVM Expression Stack Pointer; don't modify directly!
 72 
 73  private:
 74   SafePointNode*     map_not_null() const {
 75     assert(_map != nullptr, "must call stopped() to test for reset compiler map");
 76     return _map;
 77   }
 78 
 79  public:
 80   GraphKit();                   // empty constructor
 81   GraphKit(JVMState* jvms);     // the JVM state on which to operate
 82 
 83 #ifdef ASSERT
 84   ~GraphKit() {
 85     assert(failing_internal() || !has_exceptions(),
 86            "unless compilation failed, user must call transfer_exceptions_into_jvms");
 87   }
 88 #endif
 89 
 90   virtual Parse*          is_Parse()          const { return nullptr; }
 91   virtual LibraryCallKit* is_LibraryCallKit() const { return nullptr; }
 92 
 93   ciEnv*        env()               const { return _env; }
 94   PhaseGVN&     gvn()               const { return _gvn; }
 95   void*         barrier_set_state() const { return C->barrier_set_state(); }
 96 
 97   void record_for_igvn(Node* n) const { C->record_for_igvn(n); }  // delegate to Compile
 98   void remove_for_igvn(Node* n) const { C->remove_for_igvn(n); }
 99 
100   // Handy well-known nodes:
101   Node*         null()          const { return zerocon(T_OBJECT); }
102   Node*         top()           const { return C->top(); }
103   RootNode*     root()          const { return C->root(); }
104 
105   // Create or find a constant node
106   Node* intcon(jint con)        const { return _gvn.intcon(con); }
107   Node* longcon(jlong con)      const { return _gvn.longcon(con); }
108   Node* integercon(jlong con, BasicType bt)   const {
109     if (bt == T_INT) {
110       return intcon(checked_cast<jint>(con));
111     }
112     assert(bt == T_LONG, "basic type not an int or long");
113     return longcon(con);
114   }
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 != nullptr; }
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() : nullptr; }
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   // Reverses the work done by clone_map(). Should only be used when the node returned by
176   // clone_map() is ultimately not used. Calling Node::destruct directly in the previously
177   // mentioned circumstance instead of this method may result in use-after-free.
178   void destruct_map_clone(SafePointNode* sfp);
179 
180   // Set the map to a clone of the given one.
181   void set_map_clone(SafePointNode* m);
182 
183   // Tell if the compilation is failing.
184   bool failing() const { return C->failing(); }
185   bool failing_internal() const { return C->failing_internal(); }
186 
187   // Set _map to null, signalling a stop to further bytecode execution.
188   // Preserve the map intact for future use, and return it back to the caller.
189   SafePointNode* stop() { SafePointNode* m = map(); set_map(nullptr); return m; }
190 
191   // Stop, but first smash the map's inputs to null, to mark it dead.
192   void stop_and_kill_map();
193 
194   // Tell if _map is null, or control is top.
195   bool stopped();
196 
197   // Tell if this method or any caller method has exception handlers.
198   bool has_exception_handler();
199 
200   // Save an exception without blowing stack contents or other JVM state.
201   // (The extra pointer is stuck with add_req on the map, beyond the JVMS.)
202   static void set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop);
203 
204   // Recover a saved exception from its map.
205   static Node* saved_ex_oop(SafePointNode* ex_map);
206 
207   // Recover a saved exception from its map, and remove it from the map.
208   static Node* clear_saved_ex_oop(SafePointNode* ex_map);
209 
210 #ifdef ASSERT
211   // Recover a saved exception from its map, and remove it from the map.
212   static bool has_saved_ex_oop(SafePointNode* ex_map);
213 #endif
214 
215   // Push an exception in the canonical position for handlers (stack(0)).
216   void push_ex_oop(Node* ex_oop) {
217     ensure_stack(1);  // ensure room to push the exception
218     set_stack(0, ex_oop);
219     set_sp(1);
220     clean_stack(1);
221   }
222 
223   // Detach and return an exception state.
224   SafePointNode* pop_exception_state() {
225     SafePointNode* ex_map = _exceptions;
226     if (ex_map != nullptr) {
227       _exceptions = ex_map->next_exception();
228       ex_map->set_next_exception(nullptr);
229       DEBUG_ONLY(verify_exception_state(ex_map));
230     }
231     return ex_map;
232   }
233 
234   // Add an exception, using the given JVM state, without commoning.
235   void push_exception_state(SafePointNode* ex_map) {
236     DEBUG_ONLY(verify_exception_state(ex_map));
237     ex_map->set_next_exception(_exceptions);
238     _exceptions = ex_map;
239   }
240 
241   // Turn the current JVM state into an exception state, appending the ex_oop.
242   SafePointNode* make_exception_state(Node* ex_oop);
243 
244   // Add an exception, using the given JVM state.
245   // Combine all exceptions with a common exception type into a single state.
246   // (This is done via combine_exception_states.)
247   void add_exception_state(SafePointNode* ex_map);
248 
249   // Combine all exceptions of any sort whatever into a single master state.
250   SafePointNode* combine_and_pop_all_exception_states() {
251     if (_exceptions == nullptr)  return nullptr;
252     SafePointNode* phi_map = pop_exception_state();
253     SafePointNode* ex_map;
254     while ((ex_map = pop_exception_state()) != nullptr) {
255       combine_exception_states(ex_map, phi_map);
256     }
257     return phi_map;
258   }
259 
260   // Combine the two exception states, building phis as necessary.
261   // The second argument is updated to include contributions from the first.
262   void combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map);
263 
264   // Reset the map to the given state.  If there are any half-finished phis
265   // in it (created by combine_exception_states), transform them now.
266   // Returns the exception oop.  (Caller must call push_ex_oop if required.)
267   Node* use_exception_state(SafePointNode* ex_map);
268 
269   // Collect exceptions from a given JVM state into my exception list.
270   void add_exception_states_from(JVMState* jvms);
271 
272   // Collect all raised exceptions into the current JVM state.
273   // Clear the current exception list and map, returns the combined states.
274   JVMState* transfer_exceptions_into_jvms();
275 
276   // Helper to throw a built-in exception.
277   // The JVMS must allow the bytecode to be re-executed via an uncommon trap.
278   void builtin_throw(Deoptimization::DeoptReason reason);
279   void builtin_throw(Deoptimization::DeoptReason reason,
280                      ciInstance* exception_object,
281                      bool allow_too_many_traps);
282   bool builtin_throw_too_many_traps(Deoptimization::DeoptReason reason,
283                                     ciInstance* exception_object);
284  private:
285   bool is_builtin_throw_hot(Deoptimization::DeoptReason reason);
286   ciInstance* builtin_throw_exception(Deoptimization::DeoptReason reason) const;
287 
288  public:
289 
290   // Helper to check the JavaThread::_should_post_on_exceptions flag
291   // and branch to an uncommon_trap if it is true (with the specified reason and must_throw)
292   void uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
293                                                   bool must_throw) ;
294 
295   // Helper Functions for adding debug information
296   void kill_dead_locals();
297 #ifdef ASSERT
298   bool dead_locals_are_killed();
299 #endif
300   // The call may deoptimize.  Supply required JVM state as debug info.
301   // If must_throw is true, the call is guaranteed not to return normally.
302   void add_safepoint_edges(SafePointNode* call,
303                            bool must_throw = false);
304 
305   // How many stack inputs does the current BC consume?
306   // And, how does the stack change after the bytecode?
307   // Returns false if unknown.
308   bool compute_stack_effects(int& inputs, int& depth);
309 
310   // Add a fixed offset to a pointer
311   Node* basic_plus_adr(Node* base, Node* ptr, intptr_t offset) {
312     return basic_plus_adr(base, ptr, MakeConX(offset));
313   }
314   Node* basic_plus_adr(Node* base, intptr_t offset) {
315     return basic_plus_adr(base, base, MakeConX(offset));
316   }
317   // Add a variable offset to a pointer
318   Node* basic_plus_adr(Node* base, Node* offset) {
319     return basic_plus_adr(base, base, offset);
320   }
321   Node* basic_plus_adr(Node* base, Node* ptr, Node* offset);
322 
323   Node* off_heap_plus_addr(Node* ptr, intptr_t offset) {
324     return basic_plus_adr(top(), ptr, MakeConX(offset));
325   }
326 
327   Node* off_heap_plus_addr(Node* ptr, Node* offset) {
328     return basic_plus_adr(top(), ptr, offset);
329   }
330 
331   // Some convenient shortcuts for common nodes
332   Node* IfTrue(IfNode* iff)                   { return _gvn.transform(new IfTrueNode(iff));      }
333   Node* IfFalse(IfNode* iff)                  { return _gvn.transform(new IfFalseNode(iff));     }
334 
335   Node* AddI(Node* l, Node* r)                { return _gvn.transform(new AddINode(l, r));       }
336   Node* SubI(Node* l, Node* r)                { return _gvn.transform(new SubINode(l, r));       }
337   Node* MulI(Node* l, Node* r)                { return _gvn.transform(new MulINode(l, r));       }
338   Node* DivI(Node* ctl, Node* l, Node* r)     { return _gvn.transform(new DivINode(ctl, l, r));  }
339 
340   Node* AndI(Node* l, Node* r)                { return _gvn.transform(new AndINode(l, r));       }
341   Node* OrI(Node* l, Node* r)                 { return _gvn.transform(new OrINode(l, r));        }
342   Node* XorI(Node* l, Node* r)                { return _gvn.transform(new XorINode(l, r));       }
343 
344   Node* MaxI(Node* l, Node* r)                { return _gvn.transform(new MaxINode(l, r));       }
345   Node* MinI(Node* l, Node* r)                { return _gvn.transform(new MinINode(l, r));       }
346 
347   Node* LShiftI(Node* l, Node* r)             { return _gvn.transform(new LShiftINode(l, r));    }
348   Node* RShiftI(Node* l, Node* r)             { return _gvn.transform(new RShiftINode(l, r));    }
349   Node* URShiftI(Node* l, Node* r)            { return _gvn.transform(new URShiftINode(l, r));   }
350 
351   Node* CmpI(Node* l, Node* r)                { return _gvn.transform(new CmpINode(l, r));       }
352   Node* CmpL(Node* l, Node* r)                { return _gvn.transform(new CmpLNode(l, r));       }
353   Node* CmpP(Node* l, Node* r)                { return _gvn.transform(new CmpPNode(l, r));       }
354   Node* Bool(Node* cmp, BoolTest::mask relop) { return _gvn.transform(new BoolNode(cmp, relop)); }
355 
356   Node* AddP(Node* b, Node* a, Node* o)       { return _gvn.transform(AddPNode::make_with_base(b, a, o)); }
357 
358   // Convert between int and long, and size_t.
359   // (See macros ConvI2X, etc., in type.hpp for ConvI2X, etc.)
360   Node* ConvI2L(Node* offset);
361   Node* ConvI2UL(Node* offset);
362   Node* ConvL2I(Node* offset);
363   // Find out the klass of an object.
364   Node* load_object_klass(Node* object);
365   // Find out the length of an array.
366   Node* load_array_length(Node* array);
367   // Cast array allocation's length as narrow as possible.
368   // If replace_length_in_map is true, replace length with CastIINode in map.
369   // This method is invoked after creating/moving ArrayAllocationNode or in load_array_length
370   Node* array_ideal_length(AllocateArrayNode* alloc,
371                            const TypeOopPtr* oop_type,
372                            bool replace_length_in_map);
373 
374 
375   // Helper function to do a null pointer check or ZERO check based on type.
376   // Throw an exception if a given value is null.
377   // Return the value cast to not-null.
378   // Be clever about equivalent dominating null checks.
379   Node* null_check_common(Node* value, BasicType type,
380                           bool assert_null = false,
381                           Node* *null_control = nullptr,
382                           bool speculative = false);
383   Node* null_check(Node* value, BasicType type = T_OBJECT) {
384     return null_check_common(value, type, false, nullptr, !_gvn.type(value)->speculative_maybe_null());
385   }
386   Node* null_check_receiver() {
387     assert(argument(0)->bottom_type()->isa_ptr(), "must be");
388     return null_check(argument(0));
389   }
390   Node* zero_check_int(Node* value) {
391     assert(value->bottom_type()->basic_type() == T_INT,
392            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
393     return null_check_common(value, T_INT);
394   }
395   Node* zero_check_long(Node* value) {
396     assert(value->bottom_type()->basic_type() == T_LONG,
397            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
398     return null_check_common(value, T_LONG);
399   }
400   // Throw an uncommon trap if a given value is __not__ null.
401   // Return the value cast to null, and be clever about dominating checks.
402   Node* null_assert(Node* value, BasicType type = T_OBJECT) {
403     return null_check_common(value, type, true, nullptr, _gvn.type(value)->speculative_always_null());
404   }
405 
406   // Check if value is null and abort if it is
407   Node* must_be_not_null(Node* value, bool do_replace_in_map);
408 
409   // Null check oop.  Return null-path control into (*null_control).
410   // Return a cast-not-null node which depends on the not-null control.
411   // If never_see_null, use an uncommon trap (*null_control sees a top).
412   // The cast is not valid along the null path; keep a copy of the original.
413   // If safe_for_replace, then we can replace the value with the cast
414   // in the parsing map (the cast is guaranteed to dominate the map)
415   Node* null_check_oop(Node* value, Node* *null_control,
416                        bool never_see_null = false,
417                        bool safe_for_replace = false,
418                        bool speculative = false);
419 
420   // Check the null_seen bit.
421   bool seems_never_null(Node* obj, ciProfileData* data, bool& speculating);
422 
423   void guard_klass_being_initialized(Node* klass);
424   void guard_init_thread(Node* klass);
425 
426   void clinit_barrier(ciInstanceKlass* ik, ciMethod* context);
427 
428   // Check for unique class for receiver at call
429   ciKlass* profile_has_unique_klass() {
430     ciCallProfile profile = method()->call_profile_at_bci(bci());
431     if (profile.count() >= 0 &&         // no cast failures here
432         profile.has_receiver(0) &&
433         profile.morphism() == 1) {
434       return profile.receiver(0);
435     }
436     return nullptr;
437   }
438 
439   // record type from profiling with the type system
440   Node* record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind);
441   void record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc);
442   void record_profiled_parameters_for_speculation();
443   void record_profiled_return_for_speculation();
444   Node* record_profiled_receiver_for_speculation(Node* n);
445 
446   // Use the type profile to narrow an object type.
447   Node* maybe_cast_profiled_receiver(Node* not_null_obj,
448                                      const TypeKlassPtr* require_klass,
449                                      ciKlass* spec,
450                                      bool safe_for_replace);
451 
452   // Cast obj to type and emit guard unless we had too many traps here already
453   Node* maybe_cast_profiled_obj(Node* obj,
454                                 ciKlass* type,
455                                 bool not_null = false);
456 
457   // Cast obj to not-null on this path
458   Node* cast_not_null(Node* obj, bool do_replace_in_map = true);
459   // Replace all occurrences of one node by another.
460   void replace_in_map(Node* old, Node* neww);
461 
462   Node* maybe_narrow_object_type(Node* obj, ciKlass* type);
463 
464   void  push(Node* n)     { map_not_null();        _map->set_stack(_map->_jvms,   _sp++        , n); }
465   Node* pop()             { map_not_null(); return _map->stack(    _map->_jvms, --_sp             ); }
466   Node* peek(int off = 0) { map_not_null(); return _map->stack(    _map->_jvms,   _sp - off - 1   ); }
467 
468   void push_pair(Node* ldval) {
469     push(ldval);
470     push(top());  // the halfword is merely a placeholder
471   }
472   void push_pair_local(int i) {
473     // longs are stored in locals in "push" order
474     push(  local(i+0) );  // the real value
475     assert(local(i+1) == top(), "");
476     push(top());  // halfword placeholder
477   }
478   Node* pop_pair() {
479     // the second half is pushed last & popped first; it contains exactly nothing
480     Node* halfword = pop();
481     assert(halfword == top(), "");
482     // the long bits are pushed first & popped last:
483     return pop();
484   }
485   void set_pair_local(int i, Node* lval) {
486     // longs are stored in locals as a value/half pair (like doubles)
487     set_local(i+0, lval);
488     set_local(i+1, top());
489   }
490 
491   // Push the node, which may be zero, one, or two words.
492   void push_node(BasicType n_type, Node* n) {
493     int n_size = type2size[n_type];
494     if      (n_size == 1)  push(      n );  // T_INT, ...
495     else if (n_size == 2)  push_pair( n );  // T_DOUBLE, T_LONG
496     else                   { assert(n_size == 0, "must be T_VOID"); }
497   }
498 
499   Node* pop_node(BasicType n_type) {
500     int n_size = type2size[n_type];
501     if      (n_size == 1)  return pop();
502     else if (n_size == 2)  return pop_pair();
503     else                   return nullptr;
504   }
505 
506   Node* control()               const { return map_not_null()->control(); }
507   Node* i_o()                   const { return map_not_null()->i_o(); }
508   Node* returnadr()             const { return map_not_null()->returnadr(); }
509   Node* frameptr()              const { return map_not_null()->frameptr(); }
510   Node* local(uint idx)         const { map_not_null(); return _map->local(      _map->_jvms, idx); }
511   Node* stack(uint idx)         const { map_not_null(); return _map->stack(      _map->_jvms, idx); }
512   Node* argument(uint idx)      const { map_not_null(); return _map->argument(   _map->_jvms, idx); }
513   Node* monitor_box(uint idx)   const { map_not_null(); return _map->monitor_box(_map->_jvms, idx); }
514   Node* monitor_obj(uint idx)   const { map_not_null(); return _map->monitor_obj(_map->_jvms, idx); }
515 
516   void set_control  (Node* c)         { map_not_null()->set_control(c); }
517   void set_i_o      (Node* c)         { map_not_null()->set_i_o(c); }
518   void set_local(uint idx, Node* c)   { map_not_null(); _map->set_local(   _map->_jvms, idx, c); }
519   void set_stack(uint idx, Node* c)   { map_not_null(); _map->set_stack(   _map->_jvms, idx, c); }
520   void set_argument(uint idx, Node* c){ map_not_null(); _map->set_argument(_map->_jvms, idx, c); }
521   void ensure_stack(uint stk_size)    { map_not_null(); _map->ensure_stack(_map->_jvms, stk_size); }
522 
523   // Access unaliased memory
524   Node* memory(uint alias_idx);
525   Node* memory(const TypePtr *tp) { return memory(C->get_alias_index(tp)); }
526   Node* memory(Node* adr) { return memory(_gvn.type(adr)->is_ptr()); }
527 
528   // Access immutable memory
529   Node* immutable_memory() { return C->immutable_memory(); }
530 
531   // Set unaliased memory
532   void set_memory(Node* c, uint alias_idx) { merged_memory()->set_memory_at(alias_idx, c); }
533   void set_memory(Node* c, const TypePtr *tp) { set_memory(c,C->get_alias_index(tp)); }
534   void set_memory(Node* c, Node* adr) { set_memory(c,_gvn.type(adr)->is_ptr()); }
535 
536   // Get the entire memory state (probably a MergeMemNode), and reset it
537   // (The resetting prevents somebody from using the dangling Node pointer.)
538   Node* reset_memory();
539 
540   // Get the entire memory state, asserted to be a MergeMemNode.
541   MergeMemNode* merged_memory() {
542     Node* mem = map_not_null()->memory();
543     assert(mem->is_MergeMem(), "parse memory is always pre-split");
544     return mem->as_MergeMem();
545   }
546 
547   // Set the entire memory state; produce a new MergeMemNode.
548   void set_all_memory(Node* newmem);
549 
550   // Create a memory projection from the call, then set_all_memory.
551   void set_all_memory_call(Node* call, bool separate_io_proj = false);
552 
553   // Create a LoadNode, reading from the parser's memory state.
554   // (Note:  require_atomic_access is useful only with T_LONG.)
555   //
556   // We choose the unordered semantics by default because we have
557   // adapted the `do_put_xxx' and `do_get_xxx' procedures for the case
558   // of volatile fields.
559   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
560                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
561                   bool require_atomic_access = false, bool unaligned = false,
562                   bool mismatched = false, bool unsafe = false, uint8_t barrier_data = 0);
563 
564   // Create & transform a StoreNode and store the effect into the
565   // parser's memory state.
566   //
567   // We must ensure that stores of object references will be visible
568   // only after the object's initialization. So the clients of this
569   // procedure must indicate that the store requires `release'
570   // semantics, if the stored value is an object reference that might
571   // point to a new object and may become externally visible.
572   // Return the new StoreXNode
573   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
574                         MemNode::MemOrd,
575                         bool require_atomic_access = false,
576                         bool unaligned = false,
577                         bool mismatched = false,
578                         bool unsafe = false,
579                         int barrier_data = 0);
580 
581   // Perform decorated accesses
582 
583   Node* access_store_at(Node* obj,   // containing obj
584                         Node* adr,   // actual address to store val at
585                         const TypePtr* adr_type,
586                         Node* val,
587                         const Type* val_type,
588                         BasicType bt,
589                         DecoratorSet decorators);
590 
591   Node* access_load_at(Node* obj,   // containing obj
592                        Node* adr,   // actual address to load val at
593                        const TypePtr* adr_type,
594                        const Type* val_type,
595                        BasicType bt,
596                        DecoratorSet decorators);
597 
598   Node* access_load(Node* adr,   // actual address to load val at
599                     const Type* val_type,
600                     BasicType bt,
601                     DecoratorSet decorators);
602 
603   Node* access_atomic_cmpxchg_val_at(Node* obj,
604                                      Node* adr,
605                                      const TypePtr* adr_type,
606                                      int alias_idx,
607                                      Node* expected_val,
608                                      Node* new_val,
609                                      const Type* value_type,
610                                      BasicType bt,
611                                      DecoratorSet decorators);
612 
613   Node* access_atomic_cmpxchg_bool_at(Node* obj,
614                                       Node* adr,
615                                       const TypePtr* adr_type,
616                                       int alias_idx,
617                                       Node* expected_val,
618                                       Node* new_val,
619                                       const Type* value_type,
620                                       BasicType bt,
621                                       DecoratorSet decorators);
622 
623   Node* access_atomic_xchg_at(Node* obj,
624                               Node* adr,
625                               const TypePtr* adr_type,
626                               int alias_idx,
627                               Node* new_val,
628                               const Type* value_type,
629                               BasicType bt,
630                               DecoratorSet decorators);
631 
632   Node* access_atomic_add_at(Node* obj,
633                              Node* adr,
634                              const TypePtr* adr_type,
635                              int alias_idx,
636                              Node* new_val,
637                              const Type* value_type,
638                              BasicType bt,
639                              DecoratorSet decorators);
640 
641   void access_clone(Node* src, Node* dst, Node* size, bool is_array);
642 
643   // Return addressing for an array element.
644   Node* array_element_address(Node* ary, Node* idx, BasicType elembt,
645                               // Optional constraint on the array size:
646                               const TypeInt* sizetype = nullptr,
647                               // Optional control dependency (for example, on range check)
648                               Node* ctrl = nullptr);
649 
650   // Return a load of array element at idx.
651   Node* load_array_element(Node* ary, Node* idx, const TypeAryPtr* arytype, bool set_ctrl);
652 
653   //---------------- Dtrace support --------------------
654   void make_dtrace_method_entry_exit(ciMethod* method, bool is_entry);
655   void make_dtrace_method_entry(ciMethod* method) {
656     make_dtrace_method_entry_exit(method, true);
657   }
658   void make_dtrace_method_exit(ciMethod* method) {
659     make_dtrace_method_entry_exit(method, false);
660   }
661 
662   //--------------- stub generation -------------------
663  public:
664   void gen_stub(address C_function,
665                 const char *name,
666                 int is_fancy_jump,
667                 bool pass_tls,
668                 bool return_pc);
669 
670   //---------- help for generating calls --------------
671 
672   // Do a null check on the receiver as it would happen before the call to
673   // callee (with all arguments still on the stack).
674   Node* null_check_receiver_before_call(ciMethod* callee) {
675     assert(!callee->is_static(), "must be a virtual method");
676     // Callsite signature can be different from actual method being called (i.e _linkTo* sites).
677     // Use callsite signature always.
678     ciMethod* declared_method = method()->get_method_at_bci(bci());
679     const int nargs = declared_method->arg_size();
680     inc_sp(nargs);
681     Node* n = null_check_receiver();
682     dec_sp(nargs);
683     return n;
684   }
685 
686   // Fill in argument edges for the call from argument(0), argument(1), ...
687   // (The next step is to call set_edges_for_java_call.)
688   void  set_arguments_for_java_call(CallJavaNode* call);
689 
690   // Fill in non-argument edges for the call.
691   // Transform the call, and update the basics: control, i_o, memory.
692   // (The next step is usually to call set_results_for_java_call.)
693   void set_edges_for_java_call(CallJavaNode* call,
694                                bool must_throw = false, bool separate_io_proj = false);
695 
696   // Finish up a java call that was started by set_edges_for_java_call.
697   // Call add_exception on any throw arising from the call.
698   // Return the call result (transformed).
699   Node* set_results_for_java_call(CallJavaNode* call, bool separate_io_proj = false, bool deoptimize = false);
700 
701   // Similar to set_edges_for_java_call, but simplified for runtime calls.
702   void  set_predefined_output_for_runtime_call(Node* call) {
703     set_predefined_output_for_runtime_call(call, nullptr, nullptr);
704   }
705   void  set_predefined_output_for_runtime_call(Node* call,
706                                                Node* keep_mem,
707                                                const TypePtr* hook_mem);
708   Node* set_predefined_input_for_runtime_call(SafePointNode* call, Node* narrow_mem = nullptr);
709 
710   // Replace the call with the current state of the kit.  Requires
711   // that the call was generated with separate io_projs so that
712   // exceptional control flow can be handled properly.
713   void replace_call(CallNode* call, Node* result, bool do_replaced_nodes = false, bool do_asserts = true);
714 
715   // helper functions for statistics
716   void increment_counter(address counter_addr);   // increment a debug counter
717   void increment_counter(Node*   counter_addr);   // increment a debug counter
718 
719   void halt(Node* ctrl, Node* frameptr, const char* reason, bool generate_code_in_product = true);
720 
721   // Bail out to the interpreter right now
722   // The optional klass is the one causing the trap.
723   // The optional reason is debug information written to the compile log.
724   // Optional must_throw is the same as with add_safepoint_edges.
725   Node* uncommon_trap(int trap_request,
726                      ciKlass* klass = nullptr, const char* reason_string = nullptr,
727                      bool must_throw = false, bool keep_exact_action = false);
728 
729   // Shorthand, to avoid saying "Deoptimization::" so many times.
730   Node* uncommon_trap(Deoptimization::DeoptReason reason,
731                      Deoptimization::DeoptAction action,
732                      ciKlass* klass = nullptr, const char* reason_string = nullptr,
733                      bool must_throw = false, bool keep_exact_action = false) {
734     return uncommon_trap(Deoptimization::make_trap_request(reason, action),
735                   klass, reason_string, must_throw, keep_exact_action);
736   }
737 
738   // Bail out to the interpreter and keep exact action (avoid switching to Action_none).
739   Node* uncommon_trap_exact(Deoptimization::DeoptReason reason,
740                            Deoptimization::DeoptAction action,
741                            ciKlass* klass = nullptr, const char* reason_string = nullptr,
742                            bool must_throw = false) {
743     return uncommon_trap(Deoptimization::make_trap_request(reason, action),
744                   klass, reason_string, must_throw, /*keep_exact_action=*/true);
745   }
746 
747   // SP when bytecode needs to be reexecuted.
748   virtual int reexecute_sp() { return sp(); }
749 
750   // Report if there were too many traps at the current method and bci.
751   // Report if a trap was recorded, and/or PerMethodTrapLimit was exceeded.
752   // If there is no MDO at all, report no trap unless told to assume it.
753   bool too_many_traps(Deoptimization::DeoptReason reason) {
754     return C->too_many_traps(method(), bci(), reason);
755   }
756 
757   // Report if there were too many recompiles at the current method and bci.
758   bool too_many_recompiles(Deoptimization::DeoptReason reason) {
759     return C->too_many_recompiles(method(), bci(), reason);
760   }
761 
762   bool too_many_traps_or_recompiles(Deoptimization::DeoptReason reason) {
763       return C->too_many_traps_or_recompiles(method(), bci(), reason);
764   }
765 
766   // Returns the object (if any) which was created the moment before.
767   Node* just_allocated_object(Node* current_control);
768 
769   // Sync Ideal and Graph kits.
770   void sync_kit(IdealKit& ideal);
771   void final_sync(IdealKit& ideal);
772 
773   public:
774   // Helper functions for fast/slow path codes
775   Node* opt_iff(Node* region, Node* iff);
776   Node* make_runtime_call(int flags,
777                           const TypeFunc* call_type, address call_addr,
778                           const char* call_name,
779                           const TypePtr* adr_type, // null if no memory effects
780                           Node* parm0 = nullptr, Node* parm1 = nullptr,
781                           Node* parm2 = nullptr, Node* parm3 = nullptr,
782                           Node* parm4 = nullptr, Node* parm5 = nullptr,
783                           Node* parm6 = nullptr, Node* parm7 = nullptr);
784 
785   Node* sign_extend_byte(Node* in);
786   Node* sign_extend_short(Node* in);
787 
788   enum {  // flag values for make_runtime_call
789     RC_NO_FP = 1,               // CallLeafNoFPNode
790     RC_NO_IO = 2,               // do not hook IO edges
791     RC_NO_LEAF = 4,             // CallStaticJavaNode
792     RC_MUST_THROW = 8,          // flag passed to add_safepoint_edges
793     RC_NARROW_MEM = 16,         // input memory is same as output
794     RC_UNCOMMON = 32,           // freq. expected to be like uncommon trap
795     RC_VECTOR = 64,             // CallLeafVectorNode
796     RC_PURE = 128,              // CallLeaf is pure
797     RC_LEAF = 0                 // null value:  no flags set
798   };
799 
800   // merge in all memory slices from new_mem, along the given path
801   void merge_memory(Node* new_mem, Node* region, int new_path);
802   void make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize = false);
803 
804   // Helper functions to build synchronizations
805   int next_monitor();
806   Node* insert_mem_bar(int opcode, Node* precedent = nullptr);
807   Node* insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent = nullptr);
808   // Optional 'precedent' is appended as an extra edge, to force ordering.
809   FastLockNode* shared_lock(Node* obj);
810   void shared_unlock(Node* box, Node* obj);
811 
812   // helper functions for the fast path/slow path idioms
813   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);
814 
815   // Generate an instance-of idiom.  Used by both the instance-of bytecode
816   // and the reflective instance-of call.
817   Node* gen_instanceof(Node *subobj, Node* superkls, bool safe_for_replace = false);
818 
819   // Generate a check-cast idiom.  Used by both the check-cast bytecode
820   // and the array-store bytecode
821   Node* gen_checkcast( Node *subobj, Node* superkls,
822                        Node* *failure_control = nullptr );
823 
824   Node* gen_subtype_check(Node* obj, Node* superklass);
825 
826   // Exact type check used for predicted calls and casts.
827   // Rewrites (*casted_receiver) to be casted to the stronger type.
828   // (Caller is responsible for doing replace_in_map.)
829   Node* type_check_receiver(Node* receiver, ciKlass* klass, float prob,
830                             Node* *casted_receiver);
831 
832   // Inexact type check used for predicted calls.
833   Node* subtype_check_receiver(Node* receiver, ciKlass* klass,
834                                Node** casted_receiver);
835 
836   // implementation of object creation
837   Node* set_output_for_allocation(AllocateNode* alloc,
838                                   const TypeOopPtr* oop_type,
839                                   bool deoptimize_on_exception=false);
840   Node* get_layout_helper(Node* klass_node, jint& constant_value);
841   Node* new_instance(Node* klass_node,
842                      Node* slow_test = nullptr,
843                      Node* *return_size_val = nullptr,
844                      bool deoptimize_on_exception = false);
845   Node* new_array(Node* klass_node, Node* count_val, int nargs,
846                   Node* *return_size_val = nullptr,
847                   bool deoptimize_on_exception = false);
848 
849   // java.lang.String helpers
850   Node* load_String_length(Node* str, bool set_ctrl);
851   Node* load_String_value(Node* str, bool set_ctrl);
852   Node* load_String_coder(Node* str, bool set_ctrl);
853   void store_String_value(Node* str, Node* value);
854   void store_String_coder(Node* str, Node* value);
855   Node* capture_memory(const TypePtr* src_type, const TypePtr* dst_type);
856   Node* compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count);
857   void inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count);
858   void inflate_string_slow(Node* src, Node* dst, Node* start, Node* count);
859 
860   // Handy for making control flow
861   IfNode* create_and_map_if(Node* ctrl, Node* tst, float prob, float cnt) {
862     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
863     _gvn.set_type(iff, iff->Value(&_gvn)); // Value may be known at parse-time
864     // Place 'if' on worklist if it will be in graph
865     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
866     return iff;
867   }
868 
869   IfNode* create_and_xform_if(Node* ctrl, Node* tst, float prob, float cnt) {
870     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
871     _gvn.transform(iff);                           // Value may be known at parse-time
872     // Place 'if' on worklist if it will be in graph
873     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
874     return iff;
875   }
876 
877   void add_parse_predicates(int nargs = 0);
878   void add_parse_predicate(Deoptimization::DeoptReason reason, int nargs);
879 
880   Node* make_constant_from_field(ciField* field, Node* obj);
881 
882   // Vector API support (implemented in vectorIntrinsics.cpp)
883   Node* box_vector(Node* in, const TypeInstPtr* vbox_type, BasicType elem_bt, int num_elem, bool deoptimize_on_exception = false);
884   Node* unbox_vector(Node* in, const TypeInstPtr* vbox_type, BasicType elem_bt, int num_elem);
885   Node* vector_shift_count(Node* cnt, int shift_op, BasicType bt, int num_elem);
886 
887   // Helper class to support reverting to a previous parsing state.
888   // When an intrinsic makes changes before bailing out, it's necessary to restore the graph
889   // as it was. See JDK-8359344 for what can happen wrong. It's also not always possible to
890   // bailout before making changes because the bailing out decision might depend on new nodes
891   // (their types, for instance).
892   //
893   // So, if an intrinsic might cause this situation, one must start by saving the state in a
894   // SavedState by constructing it, and the state will be restored on destruction. If the
895   // intrinsic is not bailing out, one need to call discard to prevent restoring the old state.
896   class SavedState : public StackObj {
897     GraphKit* _kit;
898     int _sp;
899     JVMState* _jvms;
900     SafePointNode* _map;
901     Unique_Node_List _ctrl_succ;
902     bool _discarded;
903 
904   public:
905     SavedState(GraphKit*);
906     ~SavedState();
907     void discard();
908   };
909 };
910 
911 // Helper class to support building of control flow branches. Upon
912 // creation the map and sp at bci are cloned and restored upon de-
913 // struction. Typical use:
914 //
915 // { PreserveJVMState pjvms(this);
916 //   // code of new branch
917 // }
918 // // here the JVM state at bci is established
919 
920 class PreserveJVMState: public StackObj {
921  protected:
922   GraphKit*      _kit;
923 #ifdef ASSERT
924   int            _block;  // PO of current block, if a Parse
925   int            _bci;
926 #endif
927   SafePointNode* _map;
928   uint           _sp;
929 
930  public:
931   PreserveJVMState(GraphKit* kit, bool clone_map = true);
932   ~PreserveJVMState();
933 };
934 
935 // Helper class to build cutouts of the form if (p) ; else {x...}.
936 // The code {x...} must not fall through.
937 // The kit's main flow of control is set to the "then" continuation of if(p).
938 class BuildCutout: public PreserveJVMState {
939  public:
940   BuildCutout(GraphKit* kit, Node* p, float prob, float cnt = COUNT_UNKNOWN);
941   ~BuildCutout();
942 };
943 
944 // Helper class to preserve the original _reexecute bit and _sp and restore
945 // them back
946 class PreserveReexecuteState: public StackObj {
947  protected:
948   GraphKit*                 _kit;
949   uint                      _sp;
950   JVMState::ReexecuteState  _reexecute;
951 
952  public:
953   PreserveReexecuteState(GraphKit* kit);
954   ~PreserveReexecuteState();
955 };
956 
957 #endif // SHARE_OPTO_GRAPHKIT_HPP