1 /*
  2  * Copyright (c) 2001, 2018, 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_VM_OPTO_GRAPHKIT_HPP
 26 #define SHARE_VM_OPTO_GRAPHKIT_HPP
 27 
 28 #include "ci/ciEnv.hpp"
 29 #include "ci/ciMethodData.hpp"
 30 #include "opto/addnode.hpp"
 31 #include "opto/callnode.hpp"
 32 #include "opto/cfgnode.hpp"
 33 #include "opto/compile.hpp"
 34 #include "opto/divnode.hpp"
 35 #include "opto/mulnode.hpp"
 36 #include "opto/phaseX.hpp"
 37 #include "opto/subnode.hpp"
 38 #include "opto/type.hpp"
 39 #include "runtime/deoptimization.hpp"
 40 
 41 class FastLockNode;
 42 class FastUnlockNode;
 43 class IdealKit;
 44 class LibraryCallKit;
 45 class Parse;
 46 class RootNode;
 47 
 48 //-----------------------------------------------------------------------------
 49 //----------------------------GraphKit-----------------------------------------
 50 // Toolkit for building the common sorts of subgraphs.
 51 // Does not know about bytecode parsing or type-flow results.
 52 // It is able to create graphs implementing the semantics of most
 53 // or all bytecodes, so that it can expand intrinsics and calls.
 54 // It may depend on JVMState structure, but it must not depend
 55 // on specific bytecode streams.
 56 class GraphKit : public Phase {
 57   friend class PreserveJVMState;
 58 
 59  protected:
 60   ciEnv*            _env;       // Compilation environment
 61   PhaseGVN         &_gvn;       // Some optimizations while parsing
 62   SafePointNode*    _map;       // Parser map from JVM to Nodes
 63   SafePointNode*    _exceptions;// Parser map(s) for exception state(s)
 64   int               _bci;       // JVM Bytecode Pointer
 65   ciMethod*         _method;    // JVM Current Method
 66 
 67  private:
 68   int               _sp;        // JVM Expression Stack Pointer; don't modify directly!
 69 
 70  private:
 71   SafePointNode*     map_not_null() const {
 72     assert(_map != NULL, "must call stopped() to test for reset compiler map");
 73     return _map;
 74   }
 75 
 76  public:
 77   GraphKit();                   // empty constructor
 78   GraphKit(JVMState* jvms);     // the JVM state on which to operate
 79 
 80 #ifdef ASSERT
 81   ~GraphKit() {
 82     assert(!has_exceptions(), "user must call transfer_exceptions_into_jvms");
 83   }
 84 #endif
 85 
 86   virtual Parse*          is_Parse()          const { return NULL; }
 87   virtual LibraryCallKit* is_LibraryCallKit() const { return NULL; }
 88 
 89   ciEnv*        env()           const { return _env; }
 90   PhaseGVN&     gvn()           const { return _gvn; }
 91 
 92   void record_for_igvn(Node* n) const { C->record_for_igvn(n); }  // delegate to Compile
 93 
 94   // Handy well-known nodes:
 95   Node*         null()          const { return zerocon(T_OBJECT); }
 96   Node*         top()           const { return C->top(); }
 97   RootNode*     root()          const { return C->root(); }
 98 
 99   // Create or find a constant node
100   Node* intcon(jint con)        const { return _gvn.intcon(con); }
101   Node* longcon(jlong con)      const { return _gvn.longcon(con); }
102   Node* makecon(const Type *t)  const { return _gvn.makecon(t); }
103   Node* zerocon(BasicType bt)   const { return _gvn.zerocon(bt); }
104   // (See also macro MakeConX in type.hpp, which uses intcon or longcon.)
105 
106   // Helper for byte_map_base
107   Node* byte_map_base_node();
108 
109   jint  find_int_con(Node* n, jint value_if_unknown) {
110     return _gvn.find_int_con(n, value_if_unknown);
111   }
112   jlong find_long_con(Node* n, jlong value_if_unknown) {
113     return _gvn.find_long_con(n, value_if_unknown);
114   }
115   // (See also macro find_intptr_t_con in type.hpp, which uses one of these.)
116 
117   // JVM State accessors:
118   // Parser mapping from JVM indices into Nodes.
119   // Low slots are accessed by the StartNode::enum.
120   // Then come the locals at StartNode::Parms to StartNode::Parms+max_locals();
121   // Then come JVM stack slots.
122   // Finally come the monitors, if any.
123   // See layout accessors in class JVMState.
124 
125   SafePointNode*     map()      const { return _map; }
126   bool               has_exceptions() const { return _exceptions != NULL; }
127   JVMState*          jvms()     const { return map_not_null()->_jvms; }
128   int                sp()       const { return _sp; }
129   int                bci()      const { return _bci; }
130   Bytecodes::Code    java_bc()  const;
131   ciMethod*          method()   const { return _method; }
132 
133   void set_jvms(JVMState* jvms)       { set_map(jvms->map());
134                                         assert(jvms == this->jvms(), "sanity");
135                                         _sp = jvms->sp();
136                                         _bci = jvms->bci();
137                                         _method = jvms->has_method() ? jvms->method() : NULL; }
138   void set_map(SafePointNode* m)      { _map = m; debug_only(verify_map()); }
139   void set_sp(int sp)                 { assert(sp >= 0, "sp must be non-negative: %d", sp); _sp = sp; }
140   void clean_stack(int from_sp); // clear garbage beyond from_sp to top
141 
142   void inc_sp(int i)                  { set_sp(sp() + i); }
143   void dec_sp(int i)                  { set_sp(sp() - i); }
144   void set_bci(int bci)               { _bci = bci; }
145 
146   // Make sure jvms has current bci & sp.
147   JVMState* sync_jvms() const;
148   JVMState* sync_jvms_for_reexecute();
149 
150 #ifdef ASSERT
151   // Make sure JVMS has an updated copy of bci and sp.
152   // Also sanity-check method, depth, and monitor depth.
153   bool jvms_in_sync() const;
154 
155   // Make sure the map looks OK.
156   void verify_map() const;
157 
158   // Make sure a proposed exception state looks OK.
159   static void verify_exception_state(SafePointNode* ex_map);
160 #endif
161 
162   // Clone the existing map state.  (Implements PreserveJVMState.)
163   SafePointNode* clone_map();
164 
165   // Set the map to a clone of the given one.
166   void set_map_clone(SafePointNode* m);
167 
168   // Tell if the compilation is failing.
169   bool failing() const { return C->failing(); }
170 
171   // Set _map to NULL, signalling a stop to further bytecode execution.
172   // Preserve the map intact for future use, and return it back to the caller.
173   SafePointNode* stop() { SafePointNode* m = map(); set_map(NULL); return m; }
174 
175   // Stop, but first smash the map's inputs to NULL, to mark it dead.
176   void stop_and_kill_map();
177 
178   // Tell if _map is NULL, or control is top.
179   bool stopped();
180 
181   // Tell if this method or any caller method has exception handlers.
182   bool has_ex_handler();
183 
184   // Save an exception without blowing stack contents or other JVM state.
185   // (The extra pointer is stuck with add_req on the map, beyond the JVMS.)
186   static void set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop);
187 
188   // Recover a saved exception from its map.
189   static Node* saved_ex_oop(SafePointNode* ex_map);
190 
191   // Recover a saved exception from its map, and remove it from the map.
192   static Node* clear_saved_ex_oop(SafePointNode* ex_map);
193 
194 #ifdef ASSERT
195   // Recover a saved exception from its map, and remove it from the map.
196   static bool has_saved_ex_oop(SafePointNode* ex_map);
197 #endif
198 
199   // Push an exception in the canonical position for handlers (stack(0)).
200   void push_ex_oop(Node* ex_oop) {
201     ensure_stack(1);  // ensure room to push the exception
202     set_stack(0, ex_oop);
203     set_sp(1);
204     clean_stack(1);
205   }
206 
207   // Detach and return an exception state.
208   SafePointNode* pop_exception_state() {
209     SafePointNode* ex_map = _exceptions;
210     if (ex_map != NULL) {
211       _exceptions = ex_map->next_exception();
212       ex_map->set_next_exception(NULL);
213       debug_only(verify_exception_state(ex_map));
214     }
215     return ex_map;
216   }
217 
218   // Add an exception, using the given JVM state, without commoning.
219   void push_exception_state(SafePointNode* ex_map) {
220     debug_only(verify_exception_state(ex_map));
221     ex_map->set_next_exception(_exceptions);
222     _exceptions = ex_map;
223   }
224 
225   // Turn the current JVM state into an exception state, appending the ex_oop.
226   SafePointNode* make_exception_state(Node* ex_oop);
227 
228   // Add an exception, using the given JVM state.
229   // Combine all exceptions with a common exception type into a single state.
230   // (This is done via combine_exception_states.)
231   void add_exception_state(SafePointNode* ex_map);
232 
233   // Combine all exceptions of any sort whatever into a single master state.
234   SafePointNode* combine_and_pop_all_exception_states() {
235     if (_exceptions == NULL)  return NULL;
236     SafePointNode* phi_map = pop_exception_state();
237     SafePointNode* ex_map;
238     while ((ex_map = pop_exception_state()) != NULL) {
239       combine_exception_states(ex_map, phi_map);
240     }
241     return phi_map;
242   }
243 
244   // Combine the two exception states, building phis as necessary.
245   // The second argument is updated to include contributions from the first.
246   void combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map);
247 
248   // Reset the map to the given state.  If there are any half-finished phis
249   // in it (created by combine_exception_states), transform them now.
250   // Returns the exception oop.  (Caller must call push_ex_oop if required.)
251   Node* use_exception_state(SafePointNode* ex_map);
252 
253   // Collect exceptions from a given JVM state into my exception list.
254   void add_exception_states_from(JVMState* jvms);
255 
256   // Collect all raised exceptions into the current JVM state.
257   // Clear the current exception list and map, returns the combined states.
258   JVMState* transfer_exceptions_into_jvms();
259 
260   // Helper to throw a built-in exception.
261   // Range checks take the offending index.
262   // Cast and array store checks take the offending class.
263   // Others do not take the optional argument.
264   // The JVMS must allow the bytecode to be re-executed
265   // via an uncommon trap.
266   void builtin_throw(Deoptimization::DeoptReason reason, Node* arg = NULL);
267 
268   // Helper to check the JavaThread::_should_post_on_exceptions flag
269   // and branch to an uncommon_trap if it is true (with the specified reason and must_throw)
270   void uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
271                                                   bool must_throw) ;
272 
273   // Helper Functions for adding debug information
274   void kill_dead_locals();
275 #ifdef ASSERT
276   bool dead_locals_are_killed();
277 #endif
278   // The call may deoptimize.  Supply required JVM state as debug info.
279   // If must_throw is true, the call is guaranteed not to return normally.
280   void add_safepoint_edges(SafePointNode* call,
281                            bool must_throw = false);
282 
283   // How many stack inputs does the current BC consume?
284   // And, how does the stack change after the bytecode?
285   // Returns false if unknown.
286   bool compute_stack_effects(int& inputs, int& depth);
287 
288   // Add a fixed offset to a pointer
289   Node* basic_plus_adr(Node* base, Node* ptr, intptr_t offset) {
290     return basic_plus_adr(base, ptr, MakeConX(offset));
291   }
292   Node* basic_plus_adr(Node* base, intptr_t offset) {
293     return basic_plus_adr(base, base, MakeConX(offset));
294   }
295   // Add a variable offset to a pointer
296   Node* basic_plus_adr(Node* base, Node* offset) {
297     return basic_plus_adr(base, base, offset);
298   }
299   Node* basic_plus_adr(Node* base, Node* ptr, Node* offset);
300 
301 
302   // Some convenient shortcuts for common nodes
303   Node* IfTrue(IfNode* iff)                   { return _gvn.transform(new IfTrueNode(iff));      }
304   Node* IfFalse(IfNode* iff)                  { return _gvn.transform(new IfFalseNode(iff));     }
305 
306   Node* AddI(Node* l, Node* r)                { return _gvn.transform(new AddINode(l, r));       }
307   Node* SubI(Node* l, Node* r)                { return _gvn.transform(new SubINode(l, r));       }
308   Node* MulI(Node* l, Node* r)                { return _gvn.transform(new MulINode(l, r));       }
309   Node* DivI(Node* ctl, Node* l, Node* r)     { return _gvn.transform(new DivINode(ctl, l, r));  }
310 
311   Node* AndI(Node* l, Node* r)                { return _gvn.transform(new AndINode(l, r));       }
312   Node* OrI(Node* l, Node* r)                 { return _gvn.transform(new OrINode(l, r));        }
313   Node* XorI(Node* l, Node* r)                { return _gvn.transform(new XorINode(l, r));       }
314 
315   Node* MaxI(Node* l, Node* r)                { return _gvn.transform(new MaxINode(l, r));       }
316   Node* MinI(Node* l, Node* r)                { return _gvn.transform(new MinINode(l, r));       }
317 
318   Node* LShiftI(Node* l, Node* r)             { return _gvn.transform(new LShiftINode(l, r));    }
319   Node* RShiftI(Node* l, Node* r)             { return _gvn.transform(new RShiftINode(l, r));    }
320   Node* URShiftI(Node* l, Node* r)            { return _gvn.transform(new URShiftINode(l, r));   }
321 
322   Node* CmpI(Node* l, Node* r)                { return _gvn.transform(new CmpINode(l, r));       }
323   Node* CmpL(Node* l, Node* r)                { return _gvn.transform(new CmpLNode(l, r));       }
324   Node* CmpP(Node* l, Node* r)                { return _gvn.transform(new CmpPNode(l, r));       }
325   Node* Bool(Node* cmp, BoolTest::mask relop) { return _gvn.transform(new BoolNode(cmp, relop)); }
326 
327   Node* AddP(Node* b, Node* a, Node* o)       { return _gvn.transform(new AddPNode(b, a, o));    }
328 
329   // Convert between int and long, and size_t.
330   // (See macros ConvI2X, etc., in type.hpp for ConvI2X, etc.)
331   Node* ConvI2L(Node* offset);
332   Node* ConvI2UL(Node* offset);
333   Node* ConvL2I(Node* offset);
334   // Find out the klass of an object.
335   Node* load_object_klass(Node* object);
336   // Find out the length of an array.
337   Node* load_array_length(Node* array);
338 
339 
340   // Helper function to do a NULL pointer check or ZERO check based on type.
341   // Throw an exception if a given value is null.
342   // Return the value cast to not-null.
343   // Be clever about equivalent dominating null checks.
344   Node* null_check_common(Node* value, BasicType type,
345                           bool assert_null = false,
346                           Node* *null_control = NULL,
347                           bool speculative = false);
348   Node* null_check(Node* value, BasicType type = T_OBJECT) {
349     return null_check_common(value, type, false, NULL, !_gvn.type(value)->speculative_maybe_null());
350   }
351   Node* null_check_receiver() {
352     assert(argument(0)->bottom_type()->isa_ptr(), "must be");
353     return null_check(argument(0));
354   }
355   Node* zero_check_int(Node* value) {
356     assert(value->bottom_type()->basic_type() == T_INT,
357            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
358     return null_check_common(value, T_INT);
359   }
360   Node* zero_check_long(Node* value) {
361     assert(value->bottom_type()->basic_type() == T_LONG,
362            "wrong type: %s", type2name(value->bottom_type()->basic_type()));
363     return null_check_common(value, T_LONG);
364   }
365   // Throw an uncommon trap if a given value is __not__ null.
366   // Return the value cast to null, and be clever about dominating checks.
367   Node* null_assert(Node* value, BasicType type = T_OBJECT) {
368     return null_check_common(value, type, true, NULL, _gvn.type(value)->speculative_always_null());
369   }
370 
371   // Check if value is null and abort if it is
372   Node* must_be_not_null(Node* value, bool do_replace_in_map);
373 
374   // Null check oop.  Return null-path control into (*null_control).
375   // Return a cast-not-null node which depends on the not-null control.
376   // If never_see_null, use an uncommon trap (*null_control sees a top).
377   // The cast is not valid along the null path; keep a copy of the original.
378   // If safe_for_replace, then we can replace the value with the cast
379   // in the parsing map (the cast is guaranteed to dominate the map)
380   Node* null_check_oop(Node* value, Node* *null_control,
381                        bool never_see_null = false,
382                        bool safe_for_replace = false,
383                        bool speculative = false);
384 
385   // Check the null_seen bit.
386   bool seems_never_null(Node* obj, ciProfileData* data, bool& speculating);
387 
388   // Check for unique class for receiver at call
389   ciKlass* profile_has_unique_klass() {
390     ciCallProfile profile = method()->call_profile_at_bci(bci());
391     if (profile.count() >= 0 &&         // no cast failures here
392         profile.has_receiver(0) &&
393         profile.morphism() == 1) {
394       return profile.receiver(0);
395     }
396     return NULL;
397   }
398 
399   // record type from profiling with the type system
400   Node* record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind);
401   void record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc);
402   void record_profiled_parameters_for_speculation();
403   void record_profiled_return_for_speculation();
404   Node* record_profiled_receiver_for_speculation(Node* n);
405 
406   // Use the type profile to narrow an object type.
407   Node* maybe_cast_profiled_receiver(Node* not_null_obj,
408                                      ciKlass* require_klass,
409                                      ciKlass* spec,
410                                      bool safe_for_replace);
411 
412   // Cast obj to type and emit guard unless we had too many traps here already
413   Node* maybe_cast_profiled_obj(Node* obj,
414                                 ciKlass* type,
415                                 bool not_null = false);
416 
417   // Cast obj to not-null on this path
418   Node* cast_not_null(Node* obj, bool do_replace_in_map = true);
419   // Replace all occurrences of one node by another.
420   void replace_in_map(Node* old, Node* neww);
421 
422   void  push(Node* n)     { map_not_null();        _map->set_stack(_map->_jvms,   _sp++        , n); }
423   Node* pop()             { map_not_null(); return _map->stack(    _map->_jvms, --_sp             ); }
424   Node* peek(int off = 0) { map_not_null(); return _map->stack(    _map->_jvms,   _sp - off - 1   ); }
425 
426   void push_pair(Node* ldval) {
427     push(ldval);
428     push(top());  // the halfword is merely a placeholder
429   }
430   void push_pair_local(int i) {
431     // longs are stored in locals in "push" order
432     push(  local(i+0) );  // the real value
433     assert(local(i+1) == top(), "");
434     push(top());  // halfword placeholder
435   }
436   Node* pop_pair() {
437     // the second half is pushed last & popped first; it contains exactly nothing
438     Node* halfword = pop();
439     assert(halfword == top(), "");
440     // the long bits are pushed first & popped last:
441     return pop();
442   }
443   void set_pair_local(int i, Node* lval) {
444     // longs are stored in locals as a value/half pair (like doubles)
445     set_local(i+0, lval);
446     set_local(i+1, top());
447   }
448 
449   // Push the node, which may be zero, one, or two words.
450   void push_node(BasicType n_type, Node* n) {
451     int n_size = type2size[n_type];
452     if      (n_size == 1)  push(      n );  // T_INT, ...
453     else if (n_size == 2)  push_pair( n );  // T_DOUBLE, T_LONG
454     else                   { assert(n_size == 0, "must be T_VOID"); }
455   }
456 
457   Node* pop_node(BasicType n_type) {
458     int n_size = type2size[n_type];
459     if      (n_size == 1)  return pop();
460     else if (n_size == 2)  return pop_pair();
461     else                   return NULL;
462   }
463 
464   Node* control()               const { return map_not_null()->control(); }
465   Node* i_o()                   const { return map_not_null()->i_o(); }
466   Node* returnadr()             const { return map_not_null()->returnadr(); }
467   Node* frameptr()              const { return map_not_null()->frameptr(); }
468   Node* local(uint idx)         const { map_not_null(); return _map->local(      _map->_jvms, idx); }
469   Node* stack(uint idx)         const { map_not_null(); return _map->stack(      _map->_jvms, idx); }
470   Node* argument(uint idx)      const { map_not_null(); return _map->argument(   _map->_jvms, idx); }
471   Node* monitor_box(uint idx)   const { map_not_null(); return _map->monitor_box(_map->_jvms, idx); }
472   Node* monitor_obj(uint idx)   const { map_not_null(); return _map->monitor_obj(_map->_jvms, idx); }
473 
474   void set_control  (Node* c)         { map_not_null()->set_control(c); }
475   void set_i_o      (Node* c)         { map_not_null()->set_i_o(c); }
476   void set_local(uint idx, Node* c)   { map_not_null(); _map->set_local(   _map->_jvms, idx, c); }
477   void set_stack(uint idx, Node* c)   { map_not_null(); _map->set_stack(   _map->_jvms, idx, c); }
478   void set_argument(uint idx, Node* c){ map_not_null(); _map->set_argument(_map->_jvms, idx, c); }
479   void ensure_stack(uint stk_size)    { map_not_null(); _map->ensure_stack(_map->_jvms, stk_size); }
480 
481   // Access unaliased memory
482   Node* memory(uint alias_idx);
483   Node* memory(const TypePtr *tp) { return memory(C->get_alias_index(tp)); }
484   Node* memory(Node* adr) { return memory(_gvn.type(adr)->is_ptr()); }
485 
486   // Access immutable memory
487   Node* immutable_memory() { return C->immutable_memory(); }
488 
489   // Set unaliased memory
490   void set_memory(Node* c, uint alias_idx) { merged_memory()->set_memory_at(alias_idx, c); }
491   void set_memory(Node* c, const TypePtr *tp) { set_memory(c,C->get_alias_index(tp)); }
492   void set_memory(Node* c, Node* adr) { set_memory(c,_gvn.type(adr)->is_ptr()); }
493 
494   // Get the entire memory state (probably a MergeMemNode), and reset it
495   // (The resetting prevents somebody from using the dangling Node pointer.)
496   Node* reset_memory();
497 
498   // Get the entire memory state, asserted to be a MergeMemNode.
499   MergeMemNode* merged_memory() {
500     Node* mem = map_not_null()->memory();
501     assert(mem->is_MergeMem(), "parse memory is always pre-split");
502     return mem->as_MergeMem();
503   }
504 
505   // Set the entire memory state; produce a new MergeMemNode.
506   void set_all_memory(Node* newmem);
507 
508   // Create a memory projection from the call, then set_all_memory.
509   void set_all_memory_call(Node* call, bool separate_io_proj = false);
510 
511   // Create a LoadNode, reading from the parser's memory state.
512   // (Note:  require_atomic_access is useful only with T_LONG.)
513   //
514   // We choose the unordered semantics by default because we have
515   // adapted the `do_put_xxx' and `do_get_xxx' procedures for the case
516   // of volatile fields.
517   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
518                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
519                   bool require_atomic_access = false, bool unaligned = false,
520                   bool mismatched = false) {
521     // This version computes alias_index from bottom_type
522     return make_load(ctl, adr, t, bt, adr->bottom_type()->is_ptr(),
523                      mo, control_dependency, require_atomic_access,
524                      unaligned, mismatched);
525   }
526   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, const TypePtr* adr_type,
527                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
528                   bool require_atomic_access = false, bool unaligned = false,
529                   bool mismatched = false) {
530     // This version computes alias_index from an address type
531     assert(adr_type != NULL, "use other make_load factory");
532     return make_load(ctl, adr, t, bt, C->get_alias_index(adr_type),
533                      mo, control_dependency, require_atomic_access,
534                      unaligned, mismatched);
535   }
536   // This is the base version which is given an alias index.
537   Node* make_load(Node* ctl, Node* adr, const Type* t, BasicType bt, int adr_idx,
538                   MemNode::MemOrd mo, LoadNode::ControlDependency control_dependency = LoadNode::DependsOnlyOnTest,
539                   bool require_atomic_access = false, bool unaligned = false,
540                   bool mismatched = false);
541 
542   // Create & transform a StoreNode and store the effect into the
543   // parser's memory state.
544   //
545   // We must ensure that stores of object references will be visible
546   // only after the object's initialization. So the clients of this
547   // procedure must indicate that the store requires `release'
548   // semantics, if the stored value is an object reference that might
549   // point to a new object and may become externally visible.
550   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
551                         const TypePtr* adr_type,
552                         MemNode::MemOrd mo,
553                         bool require_atomic_access = false,
554                         bool unaligned = false,
555                         bool mismatched = false) {
556     // This version computes alias_index from an address type
557     assert(adr_type != NULL, "use other store_to_memory factory");
558     return store_to_memory(ctl, adr, val, bt,
559                            C->get_alias_index(adr_type),
560                            mo, require_atomic_access,
561                            unaligned, mismatched);
562   }
563   // This is the base version which is given alias index
564   // Return the new StoreXNode
565   Node* store_to_memory(Node* ctl, Node* adr, Node* val, BasicType bt,
566                         int adr_idx,
567                         MemNode::MemOrd,
568                         bool require_atomic_access = false,
569                         bool unaligned = false,
570                         bool mismatched = false);
571 
572 
573   // All in one pre-barrier, store, post_barrier
574   // Insert a write-barrier'd store.  This is to let generational GC
575   // work; we have to flag all oop-stores before the next GC point.
576   //
577   // It comes in 3 flavors of store to an object, array, or unknown.
578   // We use precise card marks for arrays to avoid scanning the entire
579   // array. We use imprecise for object. We use precise for unknown
580   // since we don't know if we have an array or and object or even
581   // where the object starts.
582   //
583   // If val==NULL, it is taken to be a completely unknown value. QQQ
584 
585   Node* store_oop(Node* ctl,
586                   Node* obj,   // containing obj
587                   Node* adr,   // actual adress to store val at
588                   const TypePtr* adr_type,
589                   Node* val,
590                   const TypeOopPtr* val_type,
591                   BasicType bt,
592                   bool use_precise,
593                   MemNode::MemOrd mo,
594                   bool mismatched = false);
595 
596   Node* store_oop_to_object(Node* ctl,
597                             Node* obj,   // containing obj
598                             Node* adr,   // actual adress to store val at
599                             const TypePtr* adr_type,
600                             Node* val,
601                             const TypeOopPtr* val_type,
602                             BasicType bt,
603                             MemNode::MemOrd mo) {
604     return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, false, mo);
605   }
606 
607   Node* store_oop_to_array(Node* ctl,
608                            Node* obj,   // containing obj
609                            Node* adr,   // actual adress to store val at
610                            const TypePtr* adr_type,
611                            Node* val,
612                            const TypeOopPtr* val_type,
613                            BasicType bt,
614                            MemNode::MemOrd mo) {
615     return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true, mo);
616   }
617 
618   // Could be an array or object we don't know at compile time (unsafe ref.)
619   Node* store_oop_to_unknown(Node* ctl,
620                              Node* obj,   // containing obj
621                              Node* adr,   // actual adress to store val at
622                              const TypePtr* adr_type,
623                              Node* val,
624                              BasicType bt,
625                              MemNode::MemOrd mo,
626                              bool mismatched = false);
627 
628   // For the few case where the barriers need special help
629   void pre_barrier(bool do_load, Node* ctl,
630                    Node* obj, Node* adr, uint adr_idx, Node* val, const TypeOopPtr* val_type,
631                    Node* pre_val,
632                    BasicType bt);
633 
634   void post_barrier(Node* ctl, Node* store, Node* obj, Node* adr, uint adr_idx,
635                     Node* val, BasicType bt, bool use_precise);
636 
637   // Return addressing for an array element.
638   Node* array_element_address(Node* ary, Node* idx, BasicType elembt,
639                               // Optional constraint on the array size:
640                               const TypeInt* sizetype = NULL,
641                               // Optional control dependency (for example, on range check)
642                               Node* ctrl = NULL);
643 
644   // Return a load of array element at idx.
645   Node* load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype);
646 
647   //---------------- Dtrace support --------------------
648   void make_dtrace_method_entry_exit(ciMethod* method, bool is_entry);
649   void make_dtrace_method_entry(ciMethod* method) {
650     make_dtrace_method_entry_exit(method, true);
651   }
652   void make_dtrace_method_exit(ciMethod* method) {
653     make_dtrace_method_entry_exit(method, false);
654   }
655 
656   //--------------- stub generation -------------------
657  public:
658   void gen_stub(address C_function,
659                 const char *name,
660                 int is_fancy_jump,
661                 bool pass_tls,
662                 bool return_pc);
663 
664   //---------- help for generating calls --------------
665 
666   // Do a null check on the receiver as it would happen before the call to
667   // callee (with all arguments still on the stack).
668   Node* null_check_receiver_before_call(ciMethod* callee) {
669     assert(!callee->is_static(), "must be a virtual method");
670     // Callsite signature can be different from actual method being called (i.e _linkTo* sites).
671     // Use callsite signature always.
672     ciMethod* declared_method = method()->get_method_at_bci(bci());
673     const int nargs = declared_method->arg_size();
674     inc_sp(nargs);
675     Node* n = null_check_receiver();
676     dec_sp(nargs);
677     return n;
678   }
679 
680   // Fill in argument edges for the call from argument(0), argument(1), ...
681   // (The next step is to call set_edges_for_java_call.)
682   void  set_arguments_for_java_call(CallJavaNode* call);
683 
684   // Fill in non-argument edges for the call.
685   // Transform the call, and update the basics: control, i_o, memory.
686   // (The next step is usually to call set_results_for_java_call.)
687   void set_edges_for_java_call(CallJavaNode* call,
688                                bool must_throw = false, bool separate_io_proj = false);
689 
690   // Finish up a java call that was started by set_edges_for_java_call.
691   // Call add_exception on any throw arising from the call.
692   // Return the call result (transformed).
693   Node* set_results_for_java_call(CallJavaNode* call, bool separate_io_proj = false);
694 
695   // Similar to set_edges_for_java_call, but simplified for runtime calls.
696   void  set_predefined_output_for_runtime_call(Node* call) {
697     set_predefined_output_for_runtime_call(call, NULL, NULL);
698   }
699   void  set_predefined_output_for_runtime_call(Node* call,
700                                                Node* keep_mem,
701                                                const TypePtr* hook_mem);
702   Node* set_predefined_input_for_runtime_call(SafePointNode* call);
703 
704   // Replace the call with the current state of the kit.  Requires
705   // that the call was generated with separate io_projs so that
706   // exceptional control flow can be handled properly.
707   void replace_call(CallNode* call, Node* result, bool do_replaced_nodes = false);
708 
709   // helper functions for statistics
710   void increment_counter(address counter_addr);   // increment a debug counter
711   void increment_counter(Node*   counter_addr);   // increment a debug counter
712 
713   // Bail out to the interpreter right now
714   // The optional klass is the one causing the trap.
715   // The optional reason is debug information written to the compile log.
716   // Optional must_throw is the same as with add_safepoint_edges.
717   void uncommon_trap(int trap_request,
718                      ciKlass* klass = NULL, const char* reason_string = NULL,
719                      bool must_throw = false, bool keep_exact_action = false);
720 
721   // Shorthand, to avoid saying "Deoptimization::" so many times.
722   void uncommon_trap(Deoptimization::DeoptReason reason,
723                      Deoptimization::DeoptAction action,
724                      ciKlass* klass = NULL, const char* reason_string = NULL,
725                      bool must_throw = false, bool keep_exact_action = false) {
726     uncommon_trap(Deoptimization::make_trap_request(reason, action),
727                   klass, reason_string, must_throw, keep_exact_action);
728   }
729 
730   // Bail out to the interpreter and keep exact action (avoid switching to Action_none).
731   void uncommon_trap_exact(Deoptimization::DeoptReason reason,
732                            Deoptimization::DeoptAction action,
733                            ciKlass* klass = NULL, const char* reason_string = NULL,
734                            bool must_throw = false) {
735     uncommon_trap(Deoptimization::make_trap_request(reason, action),
736                   klass, reason_string, must_throw, /*keep_exact_action=*/true);
737   }
738 
739   // SP when bytecode needs to be reexecuted.
740   virtual int reexecute_sp() { return sp(); }
741 
742   // Report if there were too many traps at the current method and bci.
743   // Report if a trap was recorded, and/or PerMethodTrapLimit was exceeded.
744   // If there is no MDO at all, report no trap unless told to assume it.
745   bool too_many_traps(Deoptimization::DeoptReason reason) {
746     return C->too_many_traps(method(), bci(), reason);
747   }
748 
749   // Report if there were too many recompiles at the current method and bci.
750   bool too_many_recompiles(Deoptimization::DeoptReason reason) {
751     return C->too_many_recompiles(method(), bci(), reason);
752   }
753 
754   // Returns the object (if any) which was created the moment before.
755   Node* just_allocated_object(Node* current_control);
756 
757   static bool use_ReduceInitialCardMarks() {
758     BarrierSet *bs = Universe::heap()->barrier_set();
759     return bs->is_a(BarrierSet::CardTableModRef)
760            && barrier_set_cast<CardTableModRefBS>(bs)->can_elide_tlab_store_barriers()
761            && ReduceInitialCardMarks;
762   }
763 
764   // Sync Ideal and Graph kits.
765   void sync_kit(IdealKit& ideal);
766   void final_sync(IdealKit& ideal);
767 
768   // vanilla/CMS post barrier
769   void write_barrier_post(Node *store, Node* obj,
770                           Node* adr,  uint adr_idx, Node* val, bool use_precise);
771 
772   // Allow reordering of pre-barrier with oop store and/or post-barrier.
773   // Used for load_store operations which loads old value.
774   bool can_move_pre_barrier() const;
775 
776   // G1 pre/post barriers
777   void g1_write_barrier_pre(bool do_load,
778                             Node* obj,
779                             Node* adr,
780                             uint alias_idx,
781                             Node* val,
782                             const TypeOopPtr* val_type,
783                             Node* pre_val,
784                             BasicType bt);
785 
786   void g1_write_barrier_post(Node* store,
787                              Node* obj,
788                              Node* adr,
789                              uint alias_idx,
790                              Node* val,
791                              BasicType bt,
792                              bool use_precise);
793   // Helper function for g1
794   private:
795   void g1_mark_card(IdealKit& ideal, Node* card_adr, Node* store, uint oop_alias_idx,
796                     Node* index, Node* index_adr,
797                     Node* buffer, const TypeFunc* tf);
798 
799   bool g1_can_remove_pre_barrier(PhaseTransform* phase, Node* adr, BasicType bt, uint adr_idx);
800 
801   bool g1_can_remove_post_barrier(PhaseTransform* phase, Node* store, Node* adr);
802 
803   public:
804   // Helper function to round double arguments before a call
805   void round_double_arguments(ciMethod* dest_method);
806   void round_double_result(ciMethod* dest_method);
807 
808   // rounding for strict float precision conformance
809   Node* precision_rounding(Node* n);
810 
811   // rounding for strict double precision conformance
812   Node* dprecision_rounding(Node* n);
813 
814   // rounding for non-strict double stores
815   Node* dstore_rounding(Node* n);
816 
817   // Helper functions for fast/slow path codes
818   Node* opt_iff(Node* region, Node* iff);
819   Node* make_runtime_call(int flags,
820                           const TypeFunc* call_type, address call_addr,
821                           const char* call_name,
822                           const TypePtr* adr_type, // NULL if no memory effects
823                           Node* parm0 = NULL, Node* parm1 = NULL,
824                           Node* parm2 = NULL, Node* parm3 = NULL,
825                           Node* parm4 = NULL, Node* parm5 = NULL,
826                           Node* parm6 = NULL, Node* parm7 = NULL);
827   enum {  // flag values for make_runtime_call
828     RC_NO_FP = 1,               // CallLeafNoFPNode
829     RC_NO_IO = 2,               // do not hook IO edges
830     RC_NO_LEAF = 4,             // CallStaticJavaNode
831     RC_MUST_THROW = 8,          // flag passed to add_safepoint_edges
832     RC_NARROW_MEM = 16,         // input memory is same as output
833     RC_UNCOMMON = 32,           // freq. expected to be like uncommon trap
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 = NULL);
844   Node* insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent = NULL);
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,
859                        Node* *failure_control = NULL );
860 
861   Node* gen_subtype_check(Node* subklass, Node* superklass) {
862     MergeMemNode* mem = merged_memory();
863     Node* ctrl = control();
864     Node* n = Phase::gen_subtype_check(subklass, superklass, &ctrl, mem, &_gvn);
865     set_control(ctrl);
866     return n;
867   }
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 
875   // implementation of object creation
876   Node* set_output_for_allocation(AllocateNode* alloc,
877                                   const TypeOopPtr* oop_type,
878                                   bool deoptimize_on_exception=false);
879   Node* get_layout_helper(Node* klass_node, jint& constant_value);
880   Node* new_instance(Node* klass_node,
881                      Node* slow_test = NULL,
882                      Node* *return_size_val = NULL,
883                      bool deoptimize_on_exception = false);
884   Node* new_array(Node* klass_node, Node* count_val, int nargs,
885                   Node* *return_size_val = NULL,
886                   bool deoptimize_on_exception = false);
887 
888   // java.lang.String helpers
889   Node* load_String_length(Node* ctrl, Node* str);
890   Node* load_String_value(Node* ctrl, Node* str);
891   Node* load_String_coder(Node* ctrl, Node* str);
892   void store_String_value(Node* ctrl, Node* str, Node* value);
893   void store_String_coder(Node* ctrl, Node* str, Node* value);
894   Node* capture_memory(const TypePtr* src_type, const TypePtr* dst_type);
895   Node* compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count);
896   void inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count);
897   void inflate_string_slow(Node* src, Node* dst, Node* start, Node* count);
898 
899   // Handy for making control flow
900   IfNode* create_and_map_if(Node* ctrl, Node* tst, float prob, float cnt) {
901     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
902     _gvn.set_type(iff, iff->Value(&_gvn)); // Value may be known at parse-time
903     // Place 'if' on worklist if it will be in graph
904     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
905     return iff;
906   }
907 
908   IfNode* create_and_xform_if(Node* ctrl, Node* tst, float prob, float cnt) {
909     IfNode* iff = new IfNode(ctrl, tst, prob, cnt);// New IfNode's
910     _gvn.transform(iff);                           // Value may be known at parse-time
911     // Place 'if' on worklist if it will be in graph
912     if (!tst->is_Con())  record_for_igvn(iff);     // Range-check and Null-check removal is later
913     return iff;
914   }
915 
916   // Insert a loop predicate into the graph
917   void add_predicate(int nargs = 0);
918   void add_predicate_impl(Deoptimization::DeoptReason reason, int nargs);
919 
920   Node* make_constant_from_field(ciField* field, Node* obj);
921 
922   // Produce new array node of stable type
923   Node* cast_array_to_stable(Node* ary, const TypeAryPtr* ary_type);
924 };
925 
926 // Helper class to support building of control flow branches. Upon
927 // creation the map and sp at bci are cloned and restored upon de-
928 // struction. Typical use:
929 //
930 // { PreserveJVMState pjvms(this);
931 //   // code of new branch
932 // }
933 // // here the JVM state at bci is established
934 
935 class PreserveJVMState: public StackObj {
936  protected:
937   GraphKit*      _kit;
938 #ifdef ASSERT
939   int            _block;  // PO of current block, if a Parse
940   int            _bci;
941 #endif
942   SafePointNode* _map;
943   uint           _sp;
944 
945  public:
946   PreserveJVMState(GraphKit* kit, bool clone_map = true);
947   ~PreserveJVMState();
948 };
949 
950 // Helper class to build cutouts of the form if (p) ; else {x...}.
951 // The code {x...} must not fall through.
952 // The kit's main flow of control is set to the "then" continuation of if(p).
953 class BuildCutout: public PreserveJVMState {
954  public:
955   BuildCutout(GraphKit* kit, Node* p, float prob, float cnt = COUNT_UNKNOWN);
956   ~BuildCutout();
957 };
958 
959 // Helper class to preserve the original _reexecute bit and _sp and restore
960 // them back
961 class PreserveReexecuteState: public StackObj {
962  protected:
963   GraphKit*                 _kit;
964   uint                      _sp;
965   JVMState::ReexecuteState  _reexecute;
966 
967  public:
968   PreserveReexecuteState(GraphKit* kit);
969   ~PreserveReexecuteState();
970 };
971 
972 #endif // SHARE_VM_OPTO_GRAPHKIT_HPP