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
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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(!has_exceptions(), "user must call transfer_exceptions_into_jvms");
 86   }
 87 #endif
 88 
 89   virtual Parse*          is_Parse()          const { return nullptr; }
 90   virtual LibraryCallKit* is_LibraryCallKit() const { return nullptr; }
 91 
 92   ciEnv*        env()               const { return _env; }
 93   PhaseGVN&     gvn()               const { return _gvn; }
 94   void*         barrier_set_state() const { return C->barrier_set_state(); }
 95 
 96   void record_for_igvn(Node* n) const { C->record_for_igvn(n); }  // delegate to Compile
 97   void remove_for_igvn(Node* n) const { C->remove_for_igvn(n); }
 98 
 99   // Handy well-known nodes:
100   Node*         null()          const { return zerocon(T_OBJECT); }
101   Node*         top()           const { return C->top(); }
102   RootNode*     root()          const { return C->root(); }
103 
104   // Create or find a constant node
105   Node* intcon(jint con)        const { return _gvn.intcon(con); }
106   Node* longcon(jlong con)      const { return _gvn.longcon(con); }
107   Node* integercon(jlong con, BasicType bt)   const {
108     if (bt == T_INT) {
109       return intcon(checked_cast<jint>(con));
110     }
111     assert(bt == T_LONG, "basic type not an int or long");
112     return longcon(con);
113   }
114   Node* makecon(const Type *t)  const { return _gvn.makecon(t); }
115   Node* zerocon(BasicType bt)   const { return _gvn.zerocon(bt); }
116   // (See also macro MakeConX in type.hpp, which uses intcon or longcon.)
117 
118   jint  find_int_con(Node* n, jint value_if_unknown) {
119     return _gvn.find_int_con(n, value_if_unknown);
120   }
121   jlong find_long_con(Node* n, jlong value_if_unknown) {
122     return _gvn.find_long_con(n, value_if_unknown);
123   }
124   // (See also macro find_intptr_t_con in type.hpp, which uses one of these.)
125 
126   // JVM State accessors:
127   // Parser mapping from JVM indices into Nodes.
128   // Low slots are accessed by the StartNode::enum.
129   // Then come the locals at StartNode::Parms to StartNode::Parms+max_locals();
130   // Then come JVM stack slots.
131   // Finally come the monitors, if any.
132   // See layout accessors in class JVMState.
133 
134   SafePointNode*     map()      const { return _map; }
135   bool               has_exceptions() const { return _exceptions != nullptr; }
136   JVMState*          jvms()     const { return map_not_null()->_jvms; }
137   int                sp()       const { return _sp; }
138   int                bci()      const { return _bci; }
139   Bytecodes::Code    java_bc()  const;
140   ciMethod*          method()   const { return _method; }
141 
142   void set_jvms(JVMState* jvms)       { set_map(jvms->map());
143                                         assert(jvms == this->jvms(), "sanity");
144                                         _sp = jvms->sp();
145                                         _bci = jvms->bci();
146                                         _method = jvms->has_method() ? jvms->method() : nullptr; }
147   void set_map(SafePointNode* m)      { _map = m; debug_only(verify_map()); }
148   void set_sp(int sp)                 { assert(sp >= 0, "sp must be non-negative: %d", sp); _sp = sp; }
149   void clean_stack(int from_sp); // clear garbage beyond from_sp to top
150 
151   void inc_sp(int i)                  { set_sp(sp() + i); }
152   void dec_sp(int i)                  { set_sp(sp() - i); }
153   void set_bci(int bci)               { _bci = bci; }
154 
155   // Make sure jvms has current bci & sp.
156   JVMState* sync_jvms() const;
157   JVMState* sync_jvms_for_reexecute();
158 
159 #ifdef ASSERT
160   // Make sure JVMS has an updated copy of bci and sp.
161   // Also sanity-check method, depth, and monitor depth.
162   bool jvms_in_sync() const;
163 
164   // Make sure the map looks OK.
165   void verify_map() const;
166 
167   // Make sure a proposed exception state looks OK.
168   static void verify_exception_state(SafePointNode* ex_map);
169 #endif
170 
171   // Clone the existing map state.  (Implements PreserveJVMState.)
172   SafePointNode* clone_map();
173 
174   // Reverses the work done by clone_map(). Should only be used when the node returned by
175   // clone_map() is ultimately not used. Calling Node::destruct directly in the previously
176   // mentioned circumstance instead of this method may result in use-after-free.
177   void destruct_map_clone(SafePointNode* sfp);
178 
179   // Set the map to a clone of the given one.
180   void set_map_clone(SafePointNode* m);
181 
182   // Tell if the compilation is failing.
183   bool failing() const { return C->failing(); }
184 
185   // Set _map to null, signalling a stop to further bytecode execution.
186   // Preserve the map intact for future use, and return it back to the caller.
187   SafePointNode* stop() { SafePointNode* m = map(); set_map(nullptr); return m; }
188 
189   // Stop, but first smash the map's inputs to null, to mark it dead.
190   void stop_and_kill_map();
191 
192   // Tell if _map is null, or control is top.
193   bool stopped();
194 
195   // Tell if this method or any caller method has exception handlers.
196   bool has_ex_handler();
197 
198   // Save an exception without blowing stack contents or other JVM state.
199   // (The extra pointer is stuck with add_req on the map, beyond the JVMS.)
200   static void set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop);
201 
202   // Recover a saved exception from its map.
203   static Node* saved_ex_oop(SafePointNode* ex_map);
204 
205   // Recover a saved exception from its map, and remove it from the map.
206   static Node* clear_saved_ex_oop(SafePointNode* ex_map);
207 
208 #ifdef ASSERT
209   // Recover a saved exception from its map, and remove it from the map.
210   static bool has_saved_ex_oop(SafePointNode* ex_map);
211 #endif
212 
213   // Push an exception in the canonical position for handlers (stack(0)).
214   void push_ex_oop(Node* ex_oop) {
215     ensure_stack(1);  // ensure room to push the exception
216     set_stack(0, ex_oop);
217     set_sp(1);
218     clean_stack(1);
219   }
220 
221   // Detach and return an exception state.
222   SafePointNode* pop_exception_state() {
223     SafePointNode* ex_map = _exceptions;
224     if (ex_map != nullptr) {
225       _exceptions = ex_map->next_exception();
226       ex_map->set_next_exception(nullptr);
227       debug_only(verify_exception_state(ex_map));
228     }
229     return ex_map;
230   }
231 
232   // Add an exception, using the given JVM state, without commoning.
233   void push_exception_state(SafePointNode* ex_map) {
234     debug_only(verify_exception_state(ex_map));
235     ex_map->set_next_exception(_exceptions);
236     _exceptions = ex_map;
237   }
238 
239   // Turn the current JVM state into an exception state, appending the ex_oop.
240   SafePointNode* make_exception_state(Node* ex_oop);
241 
242   // Add an exception, using the given JVM state.
243   // Combine all exceptions with a common exception type into a single state.
244   // (This is done via combine_exception_states.)
245   void add_exception_state(SafePointNode* ex_map);
246 
247   // Combine all exceptions of any sort whatever into a single master state.
248   SafePointNode* combine_and_pop_all_exception_states() {
249     if (_exceptions == nullptr)  return nullptr;
250     SafePointNode* phi_map = pop_exception_state();
251     SafePointNode* ex_map;
252     while ((ex_map = pop_exception_state()) != nullptr) {
253       combine_exception_states(ex_map, phi_map);
254     }
255     return phi_map;
256   }
257 
258   // Combine the two exception states, building phis as necessary.
259   // The second argument is updated to include contributions from the first.
260   void combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map);
261 
262   // Reset the map to the given state.  If there are any half-finished phis
263   // in it (created by combine_exception_states), transform them now.
264   // Returns the exception oop.  (Caller must call push_ex_oop if required.)
265   Node* use_exception_state(SafePointNode* ex_map);
266 
267   // Collect exceptions from a given JVM state into my exception list.
268   void add_exception_states_from(JVMState* jvms);
269 
270   // Collect all raised exceptions into the current JVM state.
271   // Clear the current exception list and map, returns the combined states.
272   JVMState* transfer_exceptions_into_jvms();
273 
274   // Helper to throw a built-in exception.
275   // The JVMS must allow the bytecode to be re-executed via an uncommon trap.
276   void builtin_throw(Deoptimization::DeoptReason reason);
277 
278   // Helper to check the JavaThread::_should_post_on_exceptions flag
279   // and branch to an uncommon_trap if it is true (with the specified reason and must_throw)
280   void uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
281                                                   bool must_throw) ;
282 
283   // Helper Functions for adding debug information
284   void kill_dead_locals();
285 #ifdef ASSERT
286   bool dead_locals_are_killed();
287 #endif
288   // The call may deoptimize.  Supply required JVM state as debug info.
289   // If must_throw is true, the call is guaranteed not to return normally.
290   void add_safepoint_edges(SafePointNode* call,
291                            bool must_throw = false);
292 
293   // How many stack inputs does the current BC consume?
294   // And, how does the stack change after the bytecode?
295   // Returns false if unknown.
296   bool compute_stack_effects(int& inputs, int& depth);
297 
298   // Add a fixed offset to a pointer
299   Node* basic_plus_adr(Node* base, Node* ptr, intptr_t offset) {
300     return basic_plus_adr(base, ptr, MakeConX(offset));
301   }
302   Node* basic_plus_adr(Node* base, intptr_t offset) {
303     return basic_plus_adr(base, base, MakeConX(offset));
304   }
305   // Add a variable offset to a pointer
306   Node* basic_plus_adr(Node* base, Node* offset) {
307     return basic_plus_adr(base, base, offset);
308   }
309   Node* basic_plus_adr(Node* base, Node* ptr, Node* offset);
310 
311 
312   // Some convenient shortcuts for common nodes
313   Node* IfTrue(IfNode* iff)                   { return _gvn.transform(new IfTrueNode(iff));      }
314   Node* IfFalse(IfNode* iff)                  { return _gvn.transform(new IfFalseNode(iff));     }
315 
316   Node* AddI(Node* l, Node* r)                { return _gvn.transform(new AddINode(l, r));       }
317   Node* SubI(Node* l, Node* r)                { return _gvn.transform(new SubINode(l, r));       }
318   Node* MulI(Node* l, Node* r)                { return _gvn.transform(new MulINode(l, r));       }
319   Node* DivI(Node* ctl, Node* l, Node* r)     { return _gvn.transform(new DivINode(ctl, l, r));  }
320 
321   Node* AndI(Node* l, Node* r)                { return _gvn.transform(new AndINode(l, r));       }
322   Node* OrI(Node* l, Node* r)                 { return _gvn.transform(new OrINode(l, r));        }
323   Node* XorI(Node* l, Node* r)                { return _gvn.transform(new XorINode(l, r));       }
324 
325   Node* MaxI(Node* l, Node* r)                { return _gvn.transform(new MaxINode(l, r));       }
326   Node* MinI(Node* l, Node* r)                { return _gvn.transform(new MinINode(l, r));       }
327 
328   Node* LShiftI(Node* l, Node* r)             { return _gvn.transform(new LShiftINode(l, r));    }
329   Node* RShiftI(Node* l, Node* r)             { return _gvn.transform(new RShiftINode(l, r));    }
330   Node* URShiftI(Node* l, Node* r)            { return _gvn.transform(new URShiftINode(l, r));   }
331 
332   Node* CmpI(Node* l, Node* r)                { return _gvn.transform(new CmpINode(l, r));       }
333   Node* CmpL(Node* l, Node* r)                { return _gvn.transform(new CmpLNode(l, r));       }
334   Node* CmpP(Node* l, Node* r)                { return _gvn.transform(new CmpPNode(l, r));       }
335   Node* Bool(Node* cmp, BoolTest::mask relop) { return _gvn.transform(new BoolNode(cmp, relop)); }
336 
337   Node* AddP(Node* b, Node* a, Node* o)       { return _gvn.transform(new AddPNode(b, a, o));    }
338 
339   // Convert between int and long, and size_t.
340   // (See macros ConvI2X, etc., in type.hpp for ConvI2X, etc.)
341   Node* ConvI2L(Node* offset);
342   Node* ConvI2UL(Node* offset);
343   Node* ConvL2I(Node* offset);
344   // Find out the klass of an object.
345   Node* load_object_klass(Node* object);
346   // Find out the length of an array.
347   Node* load_array_length(Node* array);
348   // Cast array allocation's length as narrow as possible.
349   // If replace_length_in_map is true, replace length with CastIINode in map.
350   // This method is invoked after creating/moving ArrayAllocationNode or in load_array_length
351   Node* array_ideal_length(AllocateArrayNode* alloc,
352                            const TypeOopPtr* oop_type,
353                            bool replace_length_in_map);
354 
355 
356   // Helper function to do a null pointer check or ZERO check based on type.
357   // Throw an exception if a given value is null.
358   // Return the value cast to not-null.
359   // Be clever about equivalent dominating null checks.
360   Node* null_check_common(Node* value, BasicType type,
361                           bool assert_null = false,
362                           Node* *null_control = nullptr,
363                           bool speculative = false);
364   Node* null_check(Node* value, BasicType type = T_OBJECT) {
365     return null_check_common(value, type, false, nullptr, !_gvn.type(value)->speculative_maybe_null());
366   }
367   Node* null_check_receiver() {
368     assert(argument(0)->bottom_type()->isa_ptr(), "must be");
369     return null_check(argument(0));
370   }
371   Node* zero_check_int(Node* value) {
372     assert(value->bottom_type()->basic_type() == T_INT,
373            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
374     return null_check_common(value, T_INT);
375   }
376   Node* zero_check_long(Node* value) {
377     assert(value->bottom_type()->basic_type() == T_LONG,
378            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
379     return null_check_common(value, T_LONG);
380   }
381   // Throw an uncommon trap if a given value is __not__ null.
382   // Return the value cast to null, and be clever about dominating checks.
383   Node* null_assert(Node* value, BasicType type = T_OBJECT) {
384     return null_check_common(value, type, true, nullptr, _gvn.type(value)->speculative_always_null());
385   }
386 
387   // Check if value is null and abort if it is
388   Node* must_be_not_null(Node* value, bool do_replace_in_map);
389 
390   // Null check oop.  Return null-path control into (*null_control).
391   // Return a cast-not-null node which depends on the not-null control.
392   // If never_see_null, use an uncommon trap (*null_control sees a top).
393   // The cast is not valid along the null path; keep a copy of the original.
394   // If safe_for_replace, then we can replace the value with the cast
395   // in the parsing map (the cast is guaranteed to dominate the map)
396   Node* null_check_oop(Node* value, Node* *null_control,
397                        bool never_see_null = false,
398                        bool safe_for_replace = false,
399                        bool speculative = false);
400 
401   // Check the null_seen bit.
402   bool seems_never_null(Node* obj, ciProfileData* data, bool& speculating);
403 
404   void guard_klass_being_initialized(Node* klass);
405   void guard_init_thread(Node* klass);
406 
407   void clinit_barrier(ciInstanceKlass* ik, ciMethod* context);
408 
409   // Check for unique class for receiver at call
410   ciKlass* profile_has_unique_klass() {
411     ciCallProfile profile = method()->call_profile_at_bci(bci());
412     if (profile.count() >= 0 &&         // no cast failures here
413         profile.has_receiver(0) &&
414         profile.morphism() == 1) {
415       return profile.receiver(0);
416     }
417     return nullptr;
418   }
419 
420   // record type from profiling with the type system
421   Node* record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind);
422   void record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc);
423   void record_profiled_parameters_for_speculation();
424   void record_profiled_return_for_speculation();
425   Node* record_profiled_receiver_for_speculation(Node* n);
426 
427   // Use the type profile to narrow an object type.
428   Node* maybe_cast_profiled_receiver(Node* not_null_obj,
429                                      const TypeKlassPtr* require_klass,
430                                      ciKlass* spec,
431                                      bool safe_for_replace);
432 
433   // Cast obj to type and emit guard unless we had too many traps here already
434   Node* maybe_cast_profiled_obj(Node* obj,
435                                 ciKlass* type,
436                                 bool not_null = false);
437 
438   // Cast obj to not-null on this path
439   Node* cast_not_null(Node* obj, bool do_replace_in_map = true);
440   // Replace all occurrences of one node by another.
441   void replace_in_map(Node* old, Node* neww);
442 
443   void  push(Node* n)     { map_not_null();        _map->set_stack(_map->_jvms,   _sp++        , n); }
444   Node* pop()             { map_not_null(); return _map->stack(    _map->_jvms, --_sp             ); }
445   Node* peek(int off = 0) { map_not_null(); return _map->stack(    _map->_jvms,   _sp - off - 1   ); }
446 
447   void push_pair(Node* ldval) {
448     push(ldval);
449     push(top());  // the halfword is merely a placeholder
450   }
451   void push_pair_local(int i) {
452     // longs are stored in locals in "push" order
453     push(  local(i+0) );  // the real value
454     assert(local(i+1) == top(), "");
455     push(top());  // halfword placeholder
456   }
457   Node* pop_pair() {
458     // the second half is pushed last & popped first; it contains exactly nothing
459     Node* halfword = pop();
460     assert(halfword == top(), "");
461     // the long bits are pushed first & popped last:
462     return pop();
463   }
464   void set_pair_local(int i, Node* lval) {
465     // longs are stored in locals as a value/half pair (like doubles)
466     set_local(i+0, lval);
467     set_local(i+1, top());
468   }
469 
470   // Push the node, which may be zero, one, or two words.
471   void push_node(BasicType n_type, Node* n) {
472     int n_size = type2size[n_type];
473     if      (n_size == 1)  push(      n );  // T_INT, ...
474     else if (n_size == 2)  push_pair( n );  // T_DOUBLE, T_LONG
475     else                   { assert(n_size == 0, "must be T_VOID"); }
476   }
477 
478   Node* pop_node(BasicType n_type) {
479     int n_size = type2size[n_type];
480     if      (n_size == 1)  return pop();
481     else if (n_size == 2)  return pop_pair();
482     else                   return nullptr;
483   }
484 
485   Node* control()               const { return map_not_null()->control(); }
486   Node* i_o()                   const { return map_not_null()->i_o(); }
487   Node* returnadr()             const { return map_not_null()->returnadr(); }
488   Node* frameptr()              const { return map_not_null()->frameptr(); }
489   Node* local(uint idx)         const { map_not_null(); return _map->local(      _map->_jvms, idx); }
490   Node* stack(uint idx)         const { map_not_null(); return _map->stack(      _map->_jvms, idx); }
491   Node* argument(uint idx)      const { map_not_null(); return _map->argument(   _map->_jvms, idx); }
492   Node* monitor_box(uint idx)   const { map_not_null(); return _map->monitor_box(_map->_jvms, idx); }
493   Node* monitor_obj(uint idx)   const { map_not_null(); return _map->monitor_obj(_map->_jvms, idx); }
494 
495   void set_control  (Node* c)         { map_not_null()->set_control(c); }
496   void set_i_o      (Node* c)         { map_not_null()->set_i_o(c); }
497   void set_local(uint idx, Node* c)   { map_not_null(); _map->set_local(   _map->_jvms, idx, c); }
498   void set_stack(uint idx, Node* c)   { map_not_null(); _map->set_stack(   _map->_jvms, idx, c); }
499   void set_argument(uint idx, Node* c){ map_not_null(); _map->set_argument(_map->_jvms, idx, c); }
500   void ensure_stack(uint stk_size)    { map_not_null(); _map->ensure_stack(_map->_jvms, stk_size); }
501 
502   // Access unaliased memory
503   Node* memory(uint alias_idx);
504   Node* memory(const TypePtr *tp) { return memory(C->get_alias_index(tp)); }
505   Node* memory(Node* adr) { return memory(_gvn.type(adr)->is_ptr()); }
506 
507   // Access immutable memory
508   Node* immutable_memory() { return C->immutable_memory(); }
509 
510   // Set unaliased memory
511   void set_memory(Node* c, uint alias_idx) { merged_memory()->set_memory_at(alias_idx, c); }
512   void set_memory(Node* c, const TypePtr *tp) { set_memory(c,C->get_alias_index(tp)); }
513   void set_memory(Node* c, Node* adr) { set_memory(c,_gvn.type(adr)->is_ptr()); }
514 
515   // Get the entire memory state (probably a MergeMemNode), and reset it
516   // (The resetting prevents somebody from using the dangling Node pointer.)
517   Node* reset_memory();
518 
519   // Get the entire memory state, asserted to be a MergeMemNode.
520   MergeMemNode* merged_memory() {
521     Node* mem = map_not_null()->memory();
522     assert(mem->is_MergeMem(), "parse memory is always pre-split");
523     return mem->as_MergeMem();
524   }
525 
526   // Set the entire memory state; produce a new MergeMemNode.
527   void set_all_memory(Node* newmem);
528 
529   // Create a memory projection from the call, then set_all_memory.
530   void set_all_memory_call(Node* call, bool separate_io_proj = false);
531 
532   // Create a LoadNode, reading from the parser's memory state.
533   // (Note:  require_atomic_access is useful only with T_LONG.)
534   //
535   // We choose the unordered semantics by default because we have
536   // adapted the `do_put_xxx' and `do_get_xxx' procedures for the case
537   // of volatile fields.
538   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
539                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
540                   bool require_atomic_access = false, bool unaligned = false,
541                   bool mismatched = false, bool unsafe = false, uint8_t barrier_data = 0) {
542     // This version computes alias_index from bottom_type
543     return make_load(ctl, adr, t, bt, adr->bottom_type()->is_ptr(),
544                      mo, control_dependency, require_atomic_access,
545                      unaligned, mismatched, unsafe, barrier_data);
546   }
547   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, const TypePtr* adr_type,
548                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
549                   bool require_atomic_access = false, bool unaligned = false,
550                   bool mismatched = false, bool unsafe = false, uint8_t barrier_data = 0) {
551     // This version computes alias_index from an address type
552     assert(adr_type != nullptr, "use other make_load factory");
553     return make_load(ctl, adr, t, bt, C->get_alias_index(adr_type),
554                      mo, control_dependency, require_atomic_access,
555                      unaligned, mismatched, unsafe, barrier_data);
556   }
557   // This is the base version which is given an alias index.
558   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, int adr_idx,
559                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
560                   bool require_atomic_access = false, bool unaligned = false,
561                   bool mismatched = false, bool unsafe = false, uint8_t barrier_data = 0);
562 
563   // Create & transform a StoreNode and store the effect into the
564   // parser's memory state.
565   //
566   // We must ensure that stores of object references will be visible
567   // only after the object's initialization. So the clients of this
568   // procedure must indicate that the store requires `release'
569   // semantics, if the stored value is an object reference that might
570   // point to a new object and may become externally visible.
571   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
572                         const TypePtr* adr_type,
573                         MemNode::MemOrd mo,
574                         bool require_atomic_access = false,
575                         bool unaligned = false,
576                         bool mismatched = false,
577                         bool unsafe = false,
578                         int barrier_data = 0) {
579     // This version computes alias_index from an address type
580     assert(adr_type != nullptr, "use other store_to_memory factory");
581     return store_to_memory(ctl, adr, val, bt,
582                            C->get_alias_index(adr_type),
583                            mo, require_atomic_access,
584                            unaligned, mismatched, unsafe,
585                            barrier_data);
586   }
587   // This is the base version which is given alias index
588   // Return the new StoreXNode
589   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
590                         int adr_idx,
591                         MemNode::MemOrd,
592                         bool require_atomic_access = false,
593                         bool unaligned = false,
594                         bool mismatched = false,
595                         bool unsafe = false,
596                         int barrier_data = 0);
597 
598   // Perform decorated accesses
599 
600   Node* access_store_at(Node* obj,   // containing obj
601                         Node* adr,   // actual address to store val at
602                         const TypePtr* adr_type,
603                         Node* val,
604                         const Type* val_type,
605                         BasicType bt,
606                         DecoratorSet decorators);
607 
608   Node* access_load_at(Node* obj,   // containing obj
609                        Node* adr,   // actual address to load val at
610                        const TypePtr* adr_type,
611                        const Type* val_type,
612                        BasicType bt,
613                        DecoratorSet decorators);
614 
615   Node* access_load(Node* adr,   // actual address to load val at
616                     const Type* val_type,
617                     BasicType bt,
618                     DecoratorSet decorators);
619 
620   Node* access_atomic_cmpxchg_val_at(Node* obj,
621                                      Node* adr,
622                                      const TypePtr* adr_type,
623                                      int alias_idx,
624                                      Node* expected_val,
625                                      Node* new_val,
626                                      const Type* value_type,
627                                      BasicType bt,
628                                      DecoratorSet decorators);
629 
630   Node* access_atomic_cmpxchg_bool_at(Node* obj,
631                                       Node* adr,
632                                       const TypePtr* adr_type,
633                                       int alias_idx,
634                                       Node* expected_val,
635                                       Node* new_val,
636                                       const Type* value_type,
637                                       BasicType bt,
638                                       DecoratorSet decorators);
639 
640   Node* access_atomic_xchg_at(Node* obj,
641                               Node* adr,
642                               const TypePtr* adr_type,
643                               int alias_idx,
644                               Node* new_val,
645                               const Type* value_type,
646                               BasicType bt,
647                               DecoratorSet decorators);
648 
649   Node* access_atomic_add_at(Node* obj,
650                              Node* adr,
651                              const TypePtr* adr_type,
652                              int alias_idx,
653                              Node* new_val,
654                              const Type* value_type,
655                              BasicType bt,
656                              DecoratorSet decorators);
657 
658   void access_clone(Node* src, Node* dst, Node* size, bool is_array);
659 
660   // Return addressing for an array element.
661   Node* array_element_address(Node* ary, Node* idx, BasicType elembt,
662                               // Optional constraint on the array size:
663                               const TypeInt* sizetype = nullptr,
664                               // Optional control dependency (for example, on range check)
665                               Node* ctrl = nullptr);
666 
667   // Return a load of array element at idx.
668   Node* load_array_element(Node* ary, Node* idx, const TypeAryPtr* arytype, bool set_ctrl);
669 
670   //---------------- Dtrace support --------------------
671   void make_dtrace_method_entry_exit(ciMethod* method, bool is_entry);
672   void make_dtrace_method_entry(ciMethod* method) {
673     make_dtrace_method_entry_exit(method, true);
674   }
675   void make_dtrace_method_exit(ciMethod* method) {
676     make_dtrace_method_entry_exit(method, false);
677   }
678 
679   //--------------- stub generation -------------------
680  public:
681   void gen_stub(address C_function,
682                 const char *name,
683                 int is_fancy_jump,
684                 bool pass_tls,
685                 bool return_pc);
686 
687   //---------- help for generating calls --------------
688 
689   // Do a null check on the receiver as it would happen before the call to
690   // callee (with all arguments still on the stack).
691   Node* null_check_receiver_before_call(ciMethod* callee) {
692     assert(!callee->is_static(), "must be a virtual method");
693     // Callsite signature can be different from actual method being called (i.e _linkTo* sites).
694     // Use callsite signature always.
695     ciMethod* declared_method = method()->get_method_at_bci(bci());
696     const int nargs = declared_method->arg_size();
697     inc_sp(nargs);
698     Node* n = null_check_receiver();
699     dec_sp(nargs);
700     return n;
701   }
702 
703   // Fill in argument edges for the call from argument(0), argument(1), ...
704   // (The next step is to call set_edges_for_java_call.)
705   void  set_arguments_for_java_call(CallJavaNode* call);
706 
707   // Fill in non-argument edges for the call.
708   // Transform the call, and update the basics: control, i_o, memory.
709   // (The next step is usually to call set_results_for_java_call.)
710   void set_edges_for_java_call(CallJavaNode* call,
711                                bool must_throw = false, bool separate_io_proj = false);
712 
713   // Finish up a java call that was started by set_edges_for_java_call.
714   // Call add_exception on any throw arising from the call.
715   // Return the call result (transformed).
716   Node* set_results_for_java_call(CallJavaNode* call, bool separate_io_proj = false, bool deoptimize = false);
717 
718   // Similar to set_edges_for_java_call, but simplified for runtime calls.
719   void  set_predefined_output_for_runtime_call(Node* call) {
720     set_predefined_output_for_runtime_call(call, nullptr, nullptr);
721   }
722   void  set_predefined_output_for_runtime_call(Node* call,
723                                                Node* keep_mem,
724                                                const TypePtr* hook_mem);
725   Node* set_predefined_input_for_runtime_call(SafePointNode* call, Node* narrow_mem = nullptr);
726 
727   // Replace the call with the current state of the kit.  Requires
728   // that the call was generated with separate io_projs so that
729   // exceptional control flow can be handled properly.
730   void replace_call(CallNode* call, Node* result, bool do_replaced_nodes = false);
731 
732   // helper functions for statistics
733   void increment_counter(address counter_addr);   // increment a debug counter
734   void increment_counter(Node*   counter_addr);   // increment a debug counter
735 
736   // Bail out to the interpreter right now
737   // The optional klass is the one causing the trap.
738   // The optional reason is debug information written to the compile log.
739   // Optional must_throw is the same as with add_safepoint_edges.
740   Node* uncommon_trap(int trap_request,
741                      ciKlass* klass = nullptr, const char* reason_string = nullptr,
742                      bool must_throw = false, bool keep_exact_action = false);
743 
744   // Shorthand, to avoid saying "Deoptimization::" so many times.
745   Node* uncommon_trap(Deoptimization::DeoptReason reason,
746                      Deoptimization::DeoptAction action,
747                      ciKlass* klass = nullptr, const char* reason_string = nullptr,
748                      bool must_throw = false, bool keep_exact_action = false) {
749     return uncommon_trap(Deoptimization::make_trap_request(reason, action),
750                   klass, reason_string, must_throw, keep_exact_action);
751   }
752 
753   // Bail out to the interpreter and keep exact action (avoid switching to Action_none).
754   Node* uncommon_trap_exact(Deoptimization::DeoptReason reason,
755                            Deoptimization::DeoptAction action,
756                            ciKlass* klass = nullptr, const char* reason_string = nullptr,
757                            bool must_throw = false) {
758     return uncommon_trap(Deoptimization::make_trap_request(reason, action),
759                   klass, reason_string, must_throw, /*keep_exact_action=*/true);
760   }
761 
762   // SP when bytecode needs to be reexecuted.
763   virtual int reexecute_sp() { return sp(); }
764 
765   // Report if there were too many traps at the current method and bci.
766   // Report if a trap was recorded, and/or PerMethodTrapLimit was exceeded.
767   // If there is no MDO at all, report no trap unless told to assume it.
768   bool too_many_traps(Deoptimization::DeoptReason reason) {
769     return C->too_many_traps(method(), bci(), reason);
770   }
771 
772   // Report if there were too many recompiles at the current method and bci.
773   bool too_many_recompiles(Deoptimization::DeoptReason reason) {
774     return C->too_many_recompiles(method(), bci(), reason);
775   }
776 
777   bool too_many_traps_or_recompiles(Deoptimization::DeoptReason reason) {
778       return C->too_many_traps_or_recompiles(method(), bci(), reason);
779   }
780 
781   // Returns the object (if any) which was created the moment before.
782   Node* just_allocated_object(Node* current_control);
783 
784   // Sync Ideal and Graph kits.
785   void sync_kit(IdealKit& ideal);
786   void final_sync(IdealKit& ideal);
787 
788   public:
789   // Helper function to round double arguments before a call
790   void round_double_arguments(ciMethod* dest_method);
791 
792   // rounding for strict float precision conformance
793   Node* precision_rounding(Node* n);
794 
795   // rounding for strict double precision conformance
796   Node* dprecision_rounding(Node* n);
797 
798   // Helper functions for fast/slow path codes
799   Node* opt_iff(Node* region, Node* iff);
800   Node* make_runtime_call(int flags,
801                           const TypeFunc* call_type, address call_addr,
802                           const char* call_name,
803                           const TypePtr* adr_type, // null if no memory effects
804                           Node* parm0 = nullptr, Node* parm1 = nullptr,
805                           Node* parm2 = nullptr, Node* parm3 = nullptr,
806                           Node* parm4 = nullptr, Node* parm5 = nullptr,
807                           Node* parm6 = nullptr, Node* parm7 = nullptr);
808 
809   Node* sign_extend_byte(Node* in);
810   Node* sign_extend_short(Node* in);
811 
812   enum {  // flag values for make_runtime_call
813     RC_NO_FP = 1,               // CallLeafNoFPNode
814     RC_NO_IO = 2,               // do not hook IO edges
815     RC_NO_LEAF = 4,             // CallStaticJavaNode
816     RC_MUST_THROW = 8,          // flag passed to add_safepoint_edges
817     RC_NARROW_MEM = 16,         // input memory is same as output
818     RC_UNCOMMON = 32,           // freq. expected to be like uncommon trap
819     RC_VECTOR = 64,             // CallLeafVectorNode
820     RC_LEAF = 0                 // null value:  no flags set
821   };
822 
823   // merge in all memory slices from new_mem, along the given path
824   void merge_memory(Node* new_mem, Node* region, int new_path);
825   void make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize = false);
826 
827   // Helper functions to build synchronizations
828   int next_monitor();
829   Node* insert_mem_bar(int opcode, Node* precedent = nullptr);
830   Node* insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent = nullptr);
831   // Optional 'precedent' is appended as an extra edge, to force ordering.
832   FastLockNode* shared_lock(Node* obj);
833   void shared_unlock(Node* box, Node* obj);
834 
835   // helper functions for the fast path/slow path idioms
836   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);
837 
838   // Generate an instance-of idiom.  Used by both the instance-of bytecode
839   // and the reflective instance-of call.
840   Node* gen_instanceof(Node *subobj, Node* superkls, bool safe_for_replace = false);
841 
842   // Generate a check-cast idiom.  Used by both the check-cast bytecode
843   // and the array-store bytecode
844   Node* gen_checkcast( Node *subobj, Node* superkls,
845                        Node* *failure_control = nullptr );
846 
847   Node* gen_subtype_check(Node* obj, Node* superklass);
848 
849   // Exact type check used for predicted calls and casts.
850   // Rewrites (*casted_receiver) to be casted to the stronger type.
851   // (Caller is responsible for doing replace_in_map.)
852   Node* type_check_receiver(Node* receiver, ciKlass* klass, float prob,
853                             Node* *casted_receiver);
854 
855   // Inexact type check used for predicted calls.
856   Node* subtype_check_receiver(Node* receiver, ciKlass* klass,
857                                Node** casted_receiver);
858 
859   // implementation of object creation
860   Node* set_output_for_allocation(AllocateNode* alloc,
861                                   const TypeOopPtr* oop_type,
862                                   bool deoptimize_on_exception=false);
863   Node* get_layout_helper(Node* klass_node, jint& constant_value);
864   Node* new_instance(Node* klass_node,
865                      Node* slow_test = nullptr,
866                      Node* *return_size_val = nullptr,
867                      bool deoptimize_on_exception = false);
868   Node* new_array(Node* klass_node, Node* count_val, int nargs,
869                   Node* *return_size_val = nullptr,
870                   bool deoptimize_on_exception = false);
871 
872   // java.lang.String helpers
873   Node* load_String_length(Node* str, bool set_ctrl);
874   Node* load_String_value(Node* str, bool set_ctrl);
875   Node* load_String_coder(Node* str, bool set_ctrl);
876   void store_String_value(Node* str, Node* value);
877   void store_String_coder(Node* str, Node* value);
878   Node* capture_memory(const TypePtr* src_type, const TypePtr* dst_type);
879   Node* compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count);
880   void inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count);
881   void inflate_string_slow(Node* src, Node* dst, Node* start, Node* count);
882 
883   // Handy for making control flow
884   IfNode* create_and_map_if(Node* ctrl, Node* tst, float prob, float cnt) {
885     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
886     _gvn.set_type(iff, iff->Value(&_gvn)); // Value may be known at parse-time
887     // Place 'if' on worklist if it will be in graph
888     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
889     return iff;
890   }
891 
892   IfNode* create_and_xform_if(Node* ctrl, Node* tst, float prob, float cnt) {
893     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
894     _gvn.transform(iff);                           // Value may be known at parse-time
895     // Place 'if' on worklist if it will be in graph
896     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
897     return iff;
898   }
899 
900   void add_parse_predicates(int nargs = 0);
901   void add_parse_predicate(Deoptimization::DeoptReason reason, int nargs);
902 
903   Node* make_constant_from_field(ciField* field, Node* obj);
904 
905   // Vector API support (implemented in vectorIntrinsics.cpp)
906   Node* box_vector(Node* in, const TypeInstPtr* vbox_type, BasicType elem_bt, int num_elem, bool deoptimize_on_exception = false);
907   Node* unbox_vector(Node* in, const TypeInstPtr* vbox_type, BasicType elem_bt, int num_elem, bool shuffle_to_vector = false);
908   Node* vector_shift_count(Node* cnt, int shift_op, BasicType bt, int num_elem);
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