1 /*
  2  * Copyright (c) 2001, 2023, 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 != nullptr, "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 = nullptr);     // the JVM state on which to operate
 86 
 87 #ifdef ASSERT
 88   ~GraphKit() {
 89     assert(failing() || !has_exceptions(),
 90            "unless compilation failed, user must call transfer_exceptions_into_jvms");
 91 #if 0
 92     // During incremental inlining, the Node_Array of the C->for_igvn() worklist and the IGVN
 93     // worklist are shared but the _in_worklist VectorSet is not. To avoid inconsistencies,
 94     // we should not add nodes to the _for_igvn worklist when using IGVN for the GraphKit.
 95     assert((_gvn.is_IterGVN() == nullptr) || (_gvn.C->for_igvn()->size() == _worklist_size),
 96            "GraphKit should not modify _for_igvn worklist after parsing");
 97 #endif
 98   }
 99 #endif
100 
101   virtual Parse*          is_Parse()          const { return nullptr; }
102   virtual LibraryCallKit* is_LibraryCallKit() const { return nullptr; }
103 
104   ciEnv*        env()               const { return _env; }
105   PhaseGVN&     gvn()               const { return _gvn; }
106   void*         barrier_set_state() const { return C->barrier_set_state(); }
107 
108   void record_for_igvn(Node* n) const { _gvn.record_for_igvn(n); }
109   void remove_for_igvn(Node* n) const { C->remove_for_igvn(n); }
110 
111   // Handy well-known nodes:
112   Node*         null()          const { return zerocon(T_OBJECT); }
113   Node*         top()           const { return C->top(); }
114   RootNode*     root()          const { return C->root(); }
115 
116   // Create or find a constant node
117   Node* intcon(jint con)        const { return _gvn.intcon(con); }
118   Node* longcon(jlong con)      const { return _gvn.longcon(con); }
119   Node* integercon(jlong con, BasicType bt)   const {
120     if (bt == T_INT) {
121       return intcon(checked_cast<jint>(con));
122     }
123     assert(bt == T_LONG, "basic type not an int or long");
124     return longcon(con);
125   }
126   Node* makecon(const Type *t)  const { return _gvn.makecon(t); }
127   Node* zerocon(BasicType bt)   const { return _gvn.zerocon(bt); }
128   // (See also macro MakeConX in type.hpp, which uses intcon or longcon.)
129 
130   jint  find_int_con(Node* n, jint value_if_unknown) {
131     return _gvn.find_int_con(n, value_if_unknown);
132   }
133   jlong find_long_con(Node* n, jlong value_if_unknown) {
134     return _gvn.find_long_con(n, value_if_unknown);
135   }
136   // (See also macro find_intptr_t_con in type.hpp, which uses one of these.)
137 
138   // JVM State accessors:
139   // Parser mapping from JVM indices into Nodes.
140   // Low slots are accessed by the StartNode::enum.
141   // Then come the locals at StartNode::Parms to StartNode::Parms+max_locals();
142   // Then come JVM stack slots.
143   // Finally come the monitors, if any.
144   // See layout accessors in class JVMState.
145 
146   SafePointNode*     map()      const { return _map; }
147   bool               has_exceptions() const { return _exceptions != nullptr; }
148   JVMState*          jvms()     const { return map_not_null()->_jvms; }
149   int                sp()       const { return _sp; }
150   int                bci()      const { return _bci; }
151   Bytecodes::Code    java_bc()  const;
152   ciMethod*          method()   const { return _method; }
153 
154   void set_jvms(JVMState* jvms)       { set_map(jvms->map());
155                                         assert(jvms == this->jvms(), "sanity");
156                                         _sp = jvms->sp();
157                                         _bci = jvms->bci();
158                                         _method = jvms->has_method() ? jvms->method() : nullptr; }
159   void set_map(SafePointNode* m)      { _map = m; debug_only(verify_map()); }
160   void set_sp(int sp)                 { assert(sp >= 0, "sp must be non-negative: %d", sp); _sp = sp; }
161   void clean_stack(int from_sp); // clear garbage beyond from_sp to top
162 
163   void inc_sp(int i)                  { set_sp(sp() + i); }
164   void dec_sp(int i)                  { set_sp(sp() - i); }
165   void set_bci(int bci)               { _bci = bci; }
166 
167   // Make sure jvms has current bci & sp.
168   JVMState* sync_jvms() const;
169   JVMState* sync_jvms_for_reexecute();
170 
171 #ifdef ASSERT
172   // Make sure JVMS has an updated copy of bci and sp.
173   // Also sanity-check method, depth, and monitor depth.
174   bool jvms_in_sync() const;
175 
176   // Make sure the map looks OK.
177   void verify_map() const;
178 
179   // Make sure a proposed exception state looks OK.
180   static void verify_exception_state(SafePointNode* ex_map);
181 #endif
182 
183   // Clone the existing map state.  (Implements PreserveJVMState.)
184   SafePointNode* clone_map();
185 
186   // Reverses the work done by clone_map(). Should only be used when the node returned by
187   // clone_map() is ultimately not used. Calling Node::destruct directly in the previously
188   // mentioned circumstance instead of this method may result in use-after-free.
189   void destruct_map_clone(SafePointNode* sfp);
190 
191   // Set the map to a clone of the given one.
192   void set_map_clone(SafePointNode* m);
193 
194   // Tell if the compilation is failing.
195   bool failing() const { return C->failing(); }
196 
197   // Set _map to null, signalling a stop to further bytecode execution.
198   // Preserve the map intact for future use, and return it back to the caller.
199   SafePointNode* stop() { SafePointNode* m = map(); set_map(nullptr); return m; }
200 
201   // Stop, but first smash the map's inputs to null, to mark it dead.
202   void stop_and_kill_map();
203 
204   // Tell if _map is null, or control is top.
205   bool stopped();
206 
207   // Tell if this method or any caller method has exception handlers.
208   bool has_exception_handler();
209 
210   // Save an exception without blowing stack contents or other JVM state.
211   // (The extra pointer is stuck with add_req on the map, beyond the JVMS.)
212   static void set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop);
213 
214   // Recover a saved exception from its map.
215   static Node* saved_ex_oop(SafePointNode* ex_map);
216 
217   // Recover a saved exception from its map, and remove it from the map.
218   static Node* clear_saved_ex_oop(SafePointNode* ex_map);
219 
220 #ifdef ASSERT
221   // Recover a saved exception from its map, and remove it from the map.
222   static bool has_saved_ex_oop(SafePointNode* ex_map);
223 #endif
224 
225   // Push an exception in the canonical position for handlers (stack(0)).
226   void push_ex_oop(Node* ex_oop) {
227     ensure_stack(1);  // ensure room to push the exception
228     set_stack(0, ex_oop);
229     set_sp(1);
230     clean_stack(1);
231   }
232 
233   // Detach and return an exception state.
234   SafePointNode* pop_exception_state() {
235     SafePointNode* ex_map = _exceptions;
236     if (ex_map != nullptr) {
237       _exceptions = ex_map->next_exception();
238       ex_map->set_next_exception(nullptr);
239       debug_only(verify_exception_state(ex_map));
240     }
241     return ex_map;
242   }
243 
244   // Add an exception, using the given JVM state, without commoning.
245   void push_exception_state(SafePointNode* ex_map) {
246     debug_only(verify_exception_state(ex_map));
247     ex_map->set_next_exception(_exceptions);
248     _exceptions = ex_map;
249   }
250 
251   // Turn the current JVM state into an exception state, appending the ex_oop.
252   SafePointNode* make_exception_state(Node* ex_oop);
253 
254   // Add an exception, using the given JVM state.
255   // Combine all exceptions with a common exception type into a single state.
256   // (This is done via combine_exception_states.)
257   void add_exception_state(SafePointNode* ex_map);
258 
259   // Combine all exceptions of any sort whatever into a single master state.
260   SafePointNode* combine_and_pop_all_exception_states() {
261     if (_exceptions == nullptr)  return nullptr;
262     SafePointNode* phi_map = pop_exception_state();
263     SafePointNode* ex_map;
264     while ((ex_map = pop_exception_state()) != nullptr) {
265       combine_exception_states(ex_map, phi_map);
266     }
267     return phi_map;
268   }
269 
270   // Combine the two exception states, building phis as necessary.
271   // The second argument is updated to include contributions from the first.
272   void combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map);
273 
274   // Reset the map to the given state.  If there are any half-finished phis
275   // in it (created by combine_exception_states), transform them now.
276   // Returns the exception oop.  (Caller must call push_ex_oop if required.)
277   Node* use_exception_state(SafePointNode* ex_map);
278 
279   // Collect exceptions from a given JVM state into my exception list.
280   void add_exception_states_from(JVMState* jvms);
281 
282   // Collect all raised exceptions into the current JVM state.
283   // Clear the current exception list and map, returns the combined states.
284   JVMState* transfer_exceptions_into_jvms();
285 
286   // Helper to throw a built-in exception.
287   // The JVMS must allow the bytecode to be re-executed via an uncommon trap.
288   void builtin_throw(Deoptimization::DeoptReason reason);
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 
324   // Some convenient shortcuts for common nodes
325   Node* IfTrue(IfNode* iff)                   { return _gvn.transform(new IfTrueNode(iff));      }
326   Node* IfFalse(IfNode* iff)                  { return _gvn.transform(new IfFalseNode(iff));     }
327 
328   Node* AddI(Node* l, Node* r)                { return _gvn.transform(new AddINode(l, r));       }
329   Node* SubI(Node* l, Node* r)                { return _gvn.transform(new SubINode(l, r));       }
330   Node* MulI(Node* l, Node* r)                { return _gvn.transform(new MulINode(l, r));       }
331   Node* DivI(Node* ctl, Node* l, Node* r)     { return _gvn.transform(new DivINode(ctl, l, r));  }
332 
333   Node* AndI(Node* l, Node* r)                { return _gvn.transform(new AndINode(l, r));       }
334   Node* OrI(Node* l, Node* r)                 { return _gvn.transform(new OrINode(l, r));        }
335   Node* XorI(Node* l, Node* r)                { return _gvn.transform(new XorINode(l, r));       }
336 
337   Node* MaxI(Node* l, Node* r)                { return _gvn.transform(new MaxINode(l, r));       }
338   Node* MinI(Node* l, Node* r)                { return _gvn.transform(new MinINode(l, r));       }
339 
340   Node* LShiftI(Node* l, Node* r)             { return _gvn.transform(new LShiftINode(l, r));    }
341   Node* RShiftI(Node* l, Node* r)             { return _gvn.transform(new RShiftINode(l, r));    }
342   Node* URShiftI(Node* l, Node* r)            { return _gvn.transform(new URShiftINode(l, r));   }
343 
344   Node* CmpI(Node* l, Node* r)                { return _gvn.transform(new CmpINode(l, r));       }
345   Node* CmpL(Node* l, Node* r)                { return _gvn.transform(new CmpLNode(l, r));       }
346   Node* CmpP(Node* l, Node* r)                { return _gvn.transform(new CmpPNode(l, r));       }
347   Node* Bool(Node* cmp, BoolTest::mask relop) { return _gvn.transform(new BoolNode(cmp, relop)); }
348 
349   Node* AddP(Node* b, Node* a, Node* o)       { return _gvn.transform(new AddPNode(b, a, o));    }
350 
351   // Convert between int and long, and size_t.
352   // (See macros ConvI2X, etc., in type.hpp for ConvI2X, etc.)
353   Node* ConvI2L(Node* offset);
354   Node* ConvI2UL(Node* offset);
355   Node* ConvL2I(Node* offset);
356   // Find out the klass of an object.
357   Node* load_object_klass(Node* object);
358   // Find out the length of an array.
359   Node* load_array_length(Node* array);
360   // Cast array allocation's length as narrow as possible.
361   // If replace_length_in_map is true, replace length with CastIINode in map.
362   // This method is invoked after creating/moving ArrayAllocationNode or in load_array_length
363   Node* array_ideal_length(AllocateArrayNode* alloc,
364                            const TypeOopPtr* oop_type,
365                            bool replace_length_in_map);
366 
367 
368   // Helper function to do a null pointer check or ZERO check based on type.
369   // Throw an exception if a given value is null.
370   // Return the value cast to not-null.
371   // Be clever about equivalent dominating null checks.
372   Node* null_check_common(Node* value, BasicType type,
373                           bool assert_null = false,
374                           Node* *null_control = nullptr,
375                           bool speculative = false,
376                           bool is_init_check = false);
377   Node* null_check(Node* value, BasicType type = T_OBJECT) {
378     return null_check_common(value, type, false, nullptr, !_gvn.type(value)->speculative_maybe_null());
379   }
380   Node* null_check_receiver() {
381     return null_check(argument(0));
382   }
383   Node* zero_check_int(Node* value) {
384     assert(value->bottom_type()->basic_type() == T_INT,
385            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
386     return null_check_common(value, T_INT);
387   }
388   Node* zero_check_long(Node* value) {
389     assert(value->bottom_type()->basic_type() == T_LONG,
390            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
391     return null_check_common(value, T_LONG);
392   }
393   // Throw an uncommon trap if a given value is __not__ null.
394   // Return the value cast to null, and be clever about dominating checks.
395   Node* null_assert(Node* value, BasicType type = T_OBJECT) {
396     return null_check_common(value, type, true, nullptr, _gvn.type(value)->speculative_always_null());
397   }
398 
399   // Check if value is null and abort if it is
400   Node* must_be_not_null(Node* value, bool do_replace_in_map);
401 
402   // Null check oop.  Return null-path control into (*null_control).
403   // Return a cast-not-null node which depends on the not-null control.
404   // If never_see_null, use an uncommon trap (*null_control sees a top).
405   // The cast is not valid along the null path; keep a copy of the original.
406   // If safe_for_replace, then we can replace the value with the cast
407   // in the parsing map (the cast is guaranteed to dominate the map)
408   Node* null_check_oop(Node* value, Node* *null_control,
409                        bool never_see_null = false,
410                        bool safe_for_replace = false,
411                        bool speculative = false);
412 
413   // Check the null_seen bit.
414   bool seems_never_null(Node* obj, ciProfileData* data, bool& speculating);
415 
416   void guard_klass_being_initialized(Node* klass);
417   void guard_init_thread(Node* klass);
418 
419   void clinit_barrier(ciInstanceKlass* ik, ciMethod* context);
420 
421   // Check for unique class for receiver at call
422   ciKlass* profile_has_unique_klass() {
423     ciCallProfile profile = method()->call_profile_at_bci(bci());
424     if (profile.count() >= 0 &&         // no cast failures here
425         profile.has_receiver(0) &&
426         profile.morphism() == 1) {
427       return profile.receiver(0);
428     }
429     return nullptr;
430   }
431 
432   // record type from profiling with the type system
433   Node* record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind);
434   void record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc);
435   void record_profiled_parameters_for_speculation();
436   void record_profiled_return_for_speculation();
437   Node* record_profiled_receiver_for_speculation(Node* n);
438 
439   // Use the type profile to narrow an object type.
440   Node* maybe_cast_profiled_receiver(Node* not_null_obj,
441                                      const TypeKlassPtr* require_klass,
442                                      ciKlass* spec,
443                                      bool safe_for_replace);
444 
445   // Cast obj to type and emit guard unless we had too many traps here already
446   Node* maybe_cast_profiled_obj(Node* obj,
447                                 ciKlass* type,
448                                 bool not_null = false);
449 
450   // Cast obj to not-null on this path
451   Node* cast_not_null(Node* obj, bool do_replace_in_map = true);
452   // Replace all occurrences of one node by another.
453   void replace_in_map(Node* old, Node* neww);
454 
455   void  push(Node* n)     { map_not_null();        _map->set_stack(_map->_jvms,   _sp++        , n); }
456   Node* pop()             { map_not_null(); return _map->stack(    _map->_jvms, --_sp             ); }
457   Node* peek(int off = 0) { map_not_null(); return _map->stack(    _map->_jvms,   _sp - off - 1   ); }
458 
459   void push_pair(Node* ldval) {
460     push(ldval);
461     push(top());  // the halfword is merely a placeholder
462   }
463   void push_pair_local(int i) {
464     // longs are stored in locals in "push" order
465     push(  local(i+0) );  // the real value
466     assert(local(i+1) == top(), "");
467     push(top());  // halfword placeholder
468   }
469   Node* pop_pair() {
470     // the second half is pushed last & popped first; it contains exactly nothing
471     Node* halfword = pop();
472     assert(halfword == top(), "");
473     // the long bits are pushed first & popped last:
474     return pop();
475   }
476   void set_pair_local(int i, Node* lval) {
477     // longs are stored in locals as a value/half pair (like doubles)
478     set_local(i+0, lval);
479     set_local(i+1, top());
480   }
481 
482   // Push the node, which may be zero, one, or two words.
483   void push_node(BasicType n_type, Node* n) {
484     int n_size = type2size[n_type];
485     if      (n_size == 1)  push(      n );  // T_INT, ...
486     else if (n_size == 2)  push_pair( n );  // T_DOUBLE, T_LONG
487     else                   { assert(n_size == 0, "must be T_VOID"); }
488   }
489 
490   Node* pop_node(BasicType n_type) {
491     int n_size = type2size[n_type];
492     if      (n_size == 1)  return pop();
493     else if (n_size == 2)  return pop_pair();
494     else                   return nullptr;
495   }
496 
497   Node* control()               const { return map_not_null()->control(); }
498   Node* i_o()                   const { return map_not_null()->i_o(); }
499   Node* returnadr()             const { return map_not_null()->returnadr(); }
500   Node* frameptr()              const { return map_not_null()->frameptr(); }
501   Node* local(uint idx)         const { map_not_null(); return _map->local(      _map->_jvms, idx); }
502   Node* stack(uint idx)         const { map_not_null(); return _map->stack(      _map->_jvms, idx); }
503   Node* argument(uint idx)      const { map_not_null(); return _map->argument(   _map->_jvms, idx); }
504   Node* monitor_box(uint idx)   const { map_not_null(); return _map->monitor_box(_map->_jvms, idx); }
505   Node* monitor_obj(uint idx)   const { map_not_null(); return _map->monitor_obj(_map->_jvms, idx); }
506 
507   void set_control  (Node* c)         { map_not_null()->set_control(c); }
508   void set_i_o      (Node* c)         { map_not_null()->set_i_o(c); }
509   void set_local(uint idx, Node* c)   { map_not_null(); _map->set_local(   _map->_jvms, idx, c); }
510   void set_stack(uint idx, Node* c)   { map_not_null(); _map->set_stack(   _map->_jvms, idx, c); }
511   void set_argument(uint idx, Node* c){ map_not_null(); _map->set_argument(_map->_jvms, idx, c); }
512   void ensure_stack(uint stk_size)    { map_not_null(); _map->ensure_stack(_map->_jvms, stk_size); }
513 
514   // Access unaliased memory
515   Node* memory(uint alias_idx);
516   Node* memory(const TypePtr *tp) { return memory(C->get_alias_index(tp)); }
517   Node* memory(Node* adr) { return memory(_gvn.type(adr)->is_ptr()); }
518 
519   // Access immutable memory
520   Node* immutable_memory() { return C->immutable_memory(); }
521 
522   // Set unaliased memory
523   void set_memory(Node* c, uint alias_idx) { merged_memory()->set_memory_at(alias_idx, c); }
524   void set_memory(Node* c, const TypePtr *tp) { set_memory(c,C->get_alias_index(tp)); }
525   void set_memory(Node* c, Node* adr) { set_memory(c,_gvn.type(adr)->is_ptr()); }
526 
527   // Get the entire memory state (probably a MergeMemNode), and reset it
528   // (The resetting prevents somebody from using the dangling Node pointer.)
529   Node* reset_memory();
530 
531   // Get the entire memory state, asserted to be a MergeMemNode.
532   MergeMemNode* merged_memory() {
533     Node* mem = map_not_null()->memory();
534     assert(mem->is_MergeMem(), "parse memory is always pre-split");
535     return mem->as_MergeMem();
536   }
537 
538   // Set the entire memory state; produce a new MergeMemNode.
539   void set_all_memory(Node* newmem);
540 
541   // Create a memory projection from the call, then set_all_memory.
542   void set_all_memory_call(Node* call, bool separate_io_proj = false);
543 
544   // Create a LoadNode, reading from the parser's memory state.
545   // (Note:  require_atomic_access is useful only with T_LONG.)
546   //
547   // We choose the unordered semantics by default because we have
548   // adapted the `do_put_xxx' and `do_get_xxx' procedures for the case
549   // of volatile fields.
550   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
551                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
552                   bool require_atomic_access = false, bool unaligned = false,
553                   bool mismatched = false, bool unsafe = false, uint8_t barrier_data = 0) {
554     // This version computes alias_index from bottom_type
555     return make_load(ctl, adr, t, bt, adr->bottom_type()->is_ptr(),
556                      mo, control_dependency, require_atomic_access,
557                      unaligned, mismatched, unsafe, barrier_data);
558   }
559   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, const TypePtr* adr_type,
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     // This version computes alias_index from an address type
564     assert(adr_type != nullptr, "use other make_load factory");
565     return make_load(ctl, adr, t, bt, C->get_alias_index(adr_type),
566                      mo, control_dependency, require_atomic_access,
567                      unaligned, mismatched, unsafe, barrier_data);
568   }
569   // This is the base version which is given an alias index.
570   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, int adr_idx,
571                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
572                   bool require_atomic_access = false, bool unaligned = false,
573                   bool mismatched = false, bool unsafe = false, uint8_t barrier_data = 0);
574 
575   // Create & transform a StoreNode and store the effect into the
576   // parser's memory state.
577   //
578   // We must ensure that stores of object references will be visible
579   // only after the object's initialization. So the clients of this
580   // procedure must indicate that the store requires `release'
581   // semantics, if the stored value is an object reference that might
582   // point to a new object and may become externally visible.
583   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
584                         const TypePtr* adr_type,
585                         MemNode::MemOrd mo,
586                         bool require_atomic_access = false,
587                         bool unaligned = false,
588                         bool mismatched = false,
589                         bool unsafe = false,
590                         int barrier_data = 0) {
591     // This version computes alias_index from an address type
592     assert(adr_type != nullptr, "use other store_to_memory factory");
593     return store_to_memory(ctl, adr, val, bt,
594                            C->get_alias_index(adr_type),
595                            mo, require_atomic_access,
596                            unaligned, mismatched, unsafe,
597                            barrier_data);
598   }
599   // This is the base version which is given alias index
600   // Return the new StoreXNode
601   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
602                         int adr_idx,
603                         MemNode::MemOrd,
604                         bool require_atomic_access = false,
605                         bool unaligned = false,
606                         bool mismatched = false,
607                         bool unsafe = false,
608                         int barrier_data = 0);
609 
610   // Perform decorated accesses
611 
612   Node* access_store_at(Node* obj,   // containing obj
613                         Node* adr,   // actual address to store val at
614                         const TypePtr* adr_type,
615                         Node* val,
616                         const Type* val_type,
617                         BasicType bt,
618                         DecoratorSet decorators,
619                         bool safe_for_replace = true);
620 
621   Node* access_load_at(Node* obj,   // containing obj
622                        Node* adr,   // actual address to load val at
623                        const TypePtr* adr_type,
624                        const Type* val_type,
625                        BasicType bt,
626                        DecoratorSet decorators,
627                        Node* ctl = nullptr);
628 
629   Node* access_load(Node* adr,   // actual address to load val at
630                     const Type* val_type,
631                     BasicType bt,
632                     DecoratorSet decorators);
633 
634   Node* access_atomic_cmpxchg_val_at(Node* obj,
635                                      Node* adr,
636                                      const TypePtr* adr_type,
637                                      int alias_idx,
638                                      Node* expected_val,
639                                      Node* new_val,
640                                      const Type* value_type,
641                                      BasicType bt,
642                                      DecoratorSet decorators);
643 
644   Node* access_atomic_cmpxchg_bool_at(Node* obj,
645                                       Node* adr,
646                                       const TypePtr* adr_type,
647                                       int alias_idx,
648                                       Node* expected_val,
649                                       Node* new_val,
650                                       const Type* value_type,
651                                       BasicType bt,
652                                       DecoratorSet decorators);
653 
654   Node* access_atomic_xchg_at(Node* obj,
655                               Node* adr,
656                               const TypePtr* adr_type,
657                               int alias_idx,
658                               Node* new_val,
659                               const Type* value_type,
660                               BasicType bt,
661                               DecoratorSet decorators);
662 
663   Node* access_atomic_add_at(Node* obj,
664                              Node* adr,
665                              const TypePtr* adr_type,
666                              int alias_idx,
667                              Node* new_val,
668                              const Type* value_type,
669                              BasicType bt,
670                              DecoratorSet decorators);
671 
672   void access_clone(Node* src, Node* dst, Node* size, bool is_array);
673 
674   // Return addressing for an array element.
675   Node* array_element_address(Node* ary, Node* idx, BasicType elembt,
676                               // Optional constraint on the array size:
677                               const TypeInt* sizetype = nullptr,
678                               // Optional control dependency (for example, on range check)
679                               Node* ctrl = nullptr);
680 
681   // Return a load of array element at idx.
682   Node* load_array_element(Node* ary, Node* idx, const TypeAryPtr* arytype, bool set_ctrl);
683 
684   //---------------- Dtrace support --------------------
685   void make_dtrace_method_entry_exit(ciMethod* method, bool is_entry);
686   void make_dtrace_method_entry(ciMethod* method) {
687     make_dtrace_method_entry_exit(method, true);
688   }
689   void make_dtrace_method_exit(ciMethod* method) {
690     make_dtrace_method_entry_exit(method, false);
691   }
692 
693   //--------------- stub generation -------------------
694  public:
695   void gen_stub(address C_function,
696                 const char *name,
697                 int is_fancy_jump,
698                 bool pass_tls,
699                 bool return_pc);
700 
701   //---------- help for generating calls --------------
702 
703   // Do a null check on the receiver as it would happen before the call to
704   // callee (with all arguments still on the stack).
705   Node* null_check_receiver_before_call(ciMethod* callee) {
706     assert(!callee->is_static(), "must be a virtual method");
707     // Callsite signature can be different from actual method being called (i.e _linkTo* sites).
708     // Use callsite signature always.
709     ciMethod* declared_method = method()->get_method_at_bci(bci());
710     const int nargs = declared_method->arg_size();
711     inc_sp(nargs);
712     Node* n = null_check_receiver();
713     dec_sp(nargs);
714     return n;
715   }
716 
717   // Fill in argument edges for the call from argument(0), argument(1), ...
718   // (The next step is to call set_edges_for_java_call.)
719   void  set_arguments_for_java_call(CallJavaNode* call, bool is_late_inline = false);
720 
721   // Fill in non-argument edges for the call.
722   // Transform the call, and update the basics: control, i_o, memory.
723   // (The next step is usually to call set_results_for_java_call.)
724   void set_edges_for_java_call(CallJavaNode* call,
725                                bool must_throw = false, bool separate_io_proj = false);
726 
727   // Finish up a java call that was started by set_edges_for_java_call.
728   // Call add_exception on any throw arising from the call.
729   // Return the call result (transformed).
730   Node* set_results_for_java_call(CallJavaNode* call, bool separate_io_proj = false, bool deoptimize = false);
731 
732   // Similar to set_edges_for_java_call, but simplified for runtime calls.
733   void  set_predefined_output_for_runtime_call(Node* call) {
734     set_predefined_output_for_runtime_call(call, nullptr, nullptr);
735   }
736   void  set_predefined_output_for_runtime_call(Node* call,
737                                                Node* keep_mem,
738                                                const TypePtr* hook_mem);
739   Node* set_predefined_input_for_runtime_call(SafePointNode* call, Node* narrow_mem = nullptr);
740 
741   // Replace the call with the current state of the kit.  Requires
742   // that the call was generated with separate io_projs so that
743   // exceptional control flow can be handled properly.
744   void replace_call(CallNode* call, Node* result, bool do_replaced_nodes = false);
745 
746   // helper functions for statistics
747   void increment_counter(address counter_addr);   // increment a debug counter
748   void increment_counter(Node*   counter_addr);   // increment a debug counter
749 
750   // Bail out to the interpreter right now
751   // The optional klass is the one causing the trap.
752   // The optional reason is debug information written to the compile log.
753   // Optional must_throw is the same as with add_safepoint_edges.
754   Node* uncommon_trap(int trap_request,
755                      ciKlass* klass = nullptr, const char* reason_string = nullptr,
756                      bool must_throw = false, bool keep_exact_action = false);
757 
758   // Shorthand, to avoid saying "Deoptimization::" so many times.
759   Node* uncommon_trap(Deoptimization::DeoptReason reason,
760                      Deoptimization::DeoptAction action,
761                      ciKlass* klass = nullptr, const char* reason_string = nullptr,
762                      bool must_throw = false, bool keep_exact_action = false) {
763     return uncommon_trap(Deoptimization::make_trap_request(reason, action),
764                   klass, reason_string, must_throw, keep_exact_action);
765   }
766 
767   // Bail out to the interpreter and keep exact action (avoid switching to Action_none).
768   Node* uncommon_trap_exact(Deoptimization::DeoptReason reason,
769                            Deoptimization::DeoptAction action,
770                            ciKlass* klass = nullptr, const char* reason_string = nullptr,
771                            bool must_throw = false) {
772     return uncommon_trap(Deoptimization::make_trap_request(reason, action),
773                   klass, reason_string, must_throw, /*keep_exact_action=*/true);
774   }
775 
776   // SP when bytecode needs to be reexecuted.
777   virtual int reexecute_sp() { return sp(); }
778 
779   // Report if there were too many traps at the current method and bci.
780   // Report if a trap was recorded, and/or PerMethodTrapLimit was exceeded.
781   // If there is no MDO at all, report no trap unless told to assume it.
782   bool too_many_traps(Deoptimization::DeoptReason reason) {
783     return C->too_many_traps(method(), bci(), reason);
784   }
785 
786   // Report if there were too many recompiles at the current method and bci.
787   bool too_many_recompiles(Deoptimization::DeoptReason reason) {
788     return C->too_many_recompiles(method(), bci(), reason);
789   }
790 
791   bool too_many_traps_or_recompiles(Deoptimization::DeoptReason reason) {
792       return C->too_many_traps_or_recompiles(method(), bci(), reason);
793   }
794 
795   // Returns the object (if any) which was created the moment before.
796   Node* just_allocated_object(Node* current_control);
797 
798   // Sync Ideal and Graph kits.
799   void sync_kit(IdealKit& ideal);
800   void final_sync(IdealKit& ideal);
801 
802   public:
803   // Helper function to round double arguments before a call
804   void round_double_arguments(ciMethod* dest_method);
805 
806   // rounding for strict float precision conformance
807   Node* precision_rounding(Node* n);
808 
809   // rounding for strict double precision conformance
810   Node* dprecision_rounding(Node* n);
811 
812   // Helper functions for fast/slow path codes
813   Node* opt_iff(Node* region, Node* iff);
814   Node* make_runtime_call(int flags,
815                           const TypeFunc* call_type, address call_addr,
816                           const char* call_name,
817                           const TypePtr* adr_type, // null if no memory effects
818                           Node* parm0 = nullptr, Node* parm1 = nullptr,
819                           Node* parm2 = nullptr, Node* parm3 = nullptr,
820                           Node* parm4 = nullptr, Node* parm5 = nullptr,
821                           Node* parm6 = nullptr, Node* parm7 = nullptr);
822 
823   Node* sign_extend_byte(Node* in);
824   Node* sign_extend_short(Node* in);
825 
826   enum {  // flag values for make_runtime_call
827     RC_NO_FP = 1,               // CallLeafNoFPNode
828     RC_NO_IO = 2,               // do not hook IO edges
829     RC_NO_LEAF = 4,             // CallStaticJavaNode
830     RC_MUST_THROW = 8,          // flag passed to add_safepoint_edges
831     RC_NARROW_MEM = 16,         // input memory is same as output
832     RC_UNCOMMON = 32,           // freq. expected to be like uncommon trap
833     RC_VECTOR = 64,             // CallLeafVectorNode
834     RC_LEAF = 0                 // null value:  no flags set
835   };
836 
837   // merge in all memory slices from new_mem, along the given path
838   void merge_memory(Node* new_mem, Node* region, int new_path);
839   void make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize = false);
840 
841   // Helper functions to build synchronizations
842   int next_monitor();
843   Node* insert_mem_bar(int opcode, Node* precedent = nullptr);
844   Node* insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent = nullptr);
845   // Optional 'precedent' is appended as an extra edge, to force ordering.
846   FastLockNode* shared_lock(Node* obj);
847   void shared_unlock(Node* box, Node* obj);
848 
849   // helper functions for the fast path/slow path idioms
850   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);
851 
852   // Generate an instance-of idiom.  Used by both the instance-of bytecode
853   // and the reflective instance-of call.
854   Node* gen_instanceof(Node *subobj, Node* superkls, bool safe_for_replace = false);
855 
856   // Generate a check-cast idiom.  Used by both the check-cast bytecode
857   // and the array-store bytecode
858   Node* gen_checkcast(Node *subobj, Node* superkls, Node* *failure_control = nullptr, bool null_free = false);
859 
860   // Inline types
861   Node* mark_word_test(Node* obj, uintptr_t mask_val, bool eq, bool check_lock = true);
862   Node* inline_type_test(Node* obj, bool is_inline = true);
863   Node* flat_array_test(Node* array_or_klass, bool flat = true);
864   Node* null_free_array_test(Node* array, bool null_free = true);
865   Node* inline_array_null_guard(Node* ary, Node* val, int nargs, bool safe_for_replace = false);
866 
867   Node* gen_subtype_check(Node* obj, Node* superklass);
868 
869   // Exact type check used for predicted calls and casts.
870   // Rewrites (*casted_receiver) to be casted to the stronger type.
871   // (Caller is responsible for doing replace_in_map.)
872   Node* type_check_receiver(Node* receiver, ciKlass* klass, float prob,
873                             Node* *casted_receiver);
874   Node* type_check(Node* recv_klass, const TypeKlassPtr* tklass, float prob);
875 
876   // Inexact type check used for predicted calls.
877   Node* subtype_check_receiver(Node* receiver, ciKlass* klass,
878                                Node** casted_receiver);
879 
880   // implementation of object creation
881   Node* set_output_for_allocation(AllocateNode* alloc,
882                                   const TypeOopPtr* oop_type,
883                                   bool deoptimize_on_exception=false);
884   Node* get_layout_helper(Node* klass_node, jint& constant_value);
885   Node* new_instance(Node* klass_node,
886                      Node* slow_test = nullptr,
887                      Node* *return_size_val = nullptr,
888                      bool deoptimize_on_exception = false,
889                      InlineTypeNode* inline_type_node = nullptr);
890   Node* new_array(Node* klass_node, Node* count_val, int nargs,
891                   Node* *return_size_val = nullptr,
892                   bool deoptimize_on_exception = false);
893 
894   // java.lang.String helpers
895   Node* load_String_length(Node* str, bool set_ctrl);
896   Node* load_String_value(Node* str, bool set_ctrl);
897   Node* load_String_coder(Node* str, bool set_ctrl);
898   void store_String_value(Node* str, Node* value);
899   void store_String_coder(Node* str, Node* value);
900   Node* capture_memory(const TypePtr* src_type, const TypePtr* dst_type);
901   Node* compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count);
902   void inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count);
903   void inflate_string_slow(Node* src, Node* dst, Node* start, Node* count);
904 
905   // Handy for making control flow
906   IfNode* create_and_map_if(Node* ctrl, Node* tst, float prob, float cnt) {
907     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
908     _gvn.set_type(iff, iff->Value(&_gvn)); // Value may be known at parse-time
909     // Place 'if' on worklist if it will be in graph
910     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
911     return iff;
912   }
913 
914   IfNode* create_and_xform_if(Node* ctrl, Node* tst, float prob, float cnt) {
915     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
916     _gvn.transform(iff);                           // Value may be known at parse-time
917     // Place 'if' on worklist if it will be in graph
918     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
919     return iff;
920   }
921 
922   void add_parse_predicates(int nargs = 0);
923   void add_parse_predicate(Deoptimization::DeoptReason reason, int nargs);
924 
925   Node* make_constant_from_field(ciField* field, Node* obj);
926   Node* load_mirror_from_klass(Node* klass);
927 
928   // Vector API support (implemented in vectorIntrinsics.cpp)
929   Node* box_vector(Node* in, const TypeInstPtr* vbox_type, BasicType elem_bt, int num_elem, bool deoptimize_on_exception = false);
930   Node* unbox_vector(Node* in, const TypeInstPtr* vbox_type, BasicType elem_bt, int num_elem, bool shuffle_to_vector = false);
931   Node* vector_shift_count(Node* cnt, int shift_op, BasicType bt, int num_elem);
932 };
933 
934 // Helper class to support building of control flow branches. Upon
935 // creation the map and sp at bci are cloned and restored upon de-
936 // struction. Typical use:
937 //
938 // { PreserveJVMState pjvms(this);
939 //   // code of new branch
940 // }
941 // // here the JVM state at bci is established
942 
943 class PreserveJVMState: public StackObj {
944  protected:
945   GraphKit*      _kit;
946 #ifdef ASSERT
947   int            _block;  // PO of current block, if a Parse
948   int            _bci;
949 #endif
950   SafePointNode* _map;
951   uint           _sp;
952 
953  public:
954   PreserveJVMState(GraphKit* kit, bool clone_map = true);
955   ~PreserveJVMState();
956 };
957 
958 // Helper class to build cutouts of the form if (p) ; else {x...}.
959 // The code {x...} must not fall through.
960 // The kit's main flow of control is set to the "then" continuation of if(p).
961 class BuildCutout: public PreserveJVMState {
962  public:
963   BuildCutout(GraphKit* kit, Node* p, float prob, float cnt = COUNT_UNKNOWN);
964   ~BuildCutout();
965 };
966 
967 // Helper class to preserve the original _reexecute bit and _sp and restore
968 // them back
969 class PreserveReexecuteState: public StackObj {
970  protected:
971   GraphKit*                 _kit;
972   uint                      _sp;
973   JVMState::ReexecuteState  _reexecute;
974 
975  public:
976   PreserveReexecuteState(GraphKit* kit);
977   ~PreserveReexecuteState();
978 };
979 
980 #endif // SHARE_OPTO_GRAPHKIT_HPP