1 /*
  2  * Copyright (c) 2005, 2025, Oracle and/or its affiliates. All rights reserved.
  3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  4  *
  5  * This code is free software; you can redistribute it and/or modify it
  6  * under the terms of the GNU General Public License version 2 only, as
  7  * published by the Free Software Foundation.
  8  *
  9  * This code is distributed in the hope that it will be useful, but WITHOUT
 10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 12  * version 2 for more details (a copy is included in the LICENSE file that
 13  * accompanied this code).
 14  *
 15  * You should have received a copy of the GNU General Public License version
 16  * 2 along with this work; if not, write to the Free Software Foundation,
 17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 18  *
 19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 20  * or visit www.oracle.com if you need additional information or have any
 21  * questions.
 22  *
 23  */
 24 
 25 #ifndef SHARE_C1_C1_LIRGENERATOR_HPP
 26 #define SHARE_C1_C1_LIRGENERATOR_HPP
 27 
 28 #include "c1/c1_Decorators.hpp"
 29 #include "c1/c1_Instruction.hpp"
 30 #include "c1/c1_LIR.hpp"
 31 #include "gc/shared/barrierSet.hpp"
 32 #include "utilities/macros.hpp"
 33 #include "utilities/sizes.hpp"
 34 
 35 class BarrierSetC1;
 36 
 37 // The classes responsible for code emission and register allocation
 38 
 39 
 40 class LIRGenerator;
 41 class LIREmitter;
 42 class Invoke;
 43 class LIRItem;
 44 
 45 typedef GrowableArray<LIRItem*> LIRItemList;
 46 
 47 class C1SwitchRange: public CompilationResourceObj {
 48  private:
 49   int _low_key;
 50   int _high_key;
 51   BlockBegin* _sux;
 52  public:
 53   C1SwitchRange(int start_key, BlockBegin* sux): _low_key(start_key), _high_key(start_key), _sux(sux) {}
 54   void set_high_key(int key) { _high_key = key; }
 55 
 56   int high_key() const { return _high_key; }
 57   int low_key() const { return _low_key; }
 58   BlockBegin* sux() const { return _sux; }
 59 };
 60 
 61 typedef GrowableArray<C1SwitchRange*> SwitchRangeArray;
 62 typedef GrowableArray<C1SwitchRange*> SwitchRangeList;
 63 
 64 class ResolveNode;
 65 
 66 typedef GrowableArray<ResolveNode*> NodeList;
 67 
 68 // Node objects form a directed graph of LIR_Opr
 69 // Edges between Nodes represent moves from one Node to its destinations
 70 class ResolveNode: public CompilationResourceObj {
 71  private:
 72   LIR_Opr    _operand;       // the source or destinaton
 73   NodeList   _destinations;  // for the operand
 74   bool       _assigned;      // Value assigned to this Node?
 75   bool       _visited;       // Node already visited?
 76   bool       _start_node;    // Start node already visited?
 77 
 78  public:
 79   ResolveNode(LIR_Opr operand)
 80     : _operand(operand)
 81     , _assigned(false)
 82     , _visited(false)
 83     , _start_node(false) {};
 84 
 85   // accessors
 86   LIR_Opr operand() const           { return _operand; }
 87   int no_of_destinations() const    { return _destinations.length(); }
 88   ResolveNode* destination_at(int i)     { return _destinations.at(i); }
 89   bool assigned() const             { return _assigned; }
 90   bool visited() const              { return _visited; }
 91   bool start_node() const           { return _start_node; }
 92 
 93   // modifiers
 94   void append(ResolveNode* dest)         { _destinations.append(dest); }
 95   void set_assigned()               { _assigned = true; }
 96   void set_visited()                { _visited = true; }
 97   void set_start_node()             { _start_node = true; }
 98 };
 99 
100 
101 // This is shared state to be used by the PhiResolver so the operand
102 // arrays don't have to be reallocated for each resolution.
103 class PhiResolverState: public CompilationResourceObj {
104   friend class PhiResolver;
105 
106  private:
107   NodeList _virtual_operands; // Nodes where the operand is a virtual register
108   NodeList _other_operands;   // Nodes where the operand is not a virtual register
109   NodeList _vreg_table;       // Mapping from virtual register to Node
110 
111  public:
112   PhiResolverState() {}
113 
114   void reset();
115 };
116 
117 
118 // class used to move value of phi operand to phi function
119 class PhiResolver: public CompilationResourceObj {
120  private:
121   LIRGenerator*     _gen;
122   PhiResolverState& _state; // temporary state cached by LIRGenerator
123 
124   ResolveNode*   _loop;
125   LIR_Opr _temp;
126 
127   // access to shared state arrays
128   NodeList& virtual_operands() { return _state._virtual_operands; }
129   NodeList& other_operands()   { return _state._other_operands;   }
130   NodeList& vreg_table()       { return _state._vreg_table;       }
131 
132   ResolveNode* create_node(LIR_Opr opr, bool source);
133   ResolveNode* source_node(LIR_Opr opr)      { return create_node(opr, true); }
134   ResolveNode* destination_node(LIR_Opr opr) { return create_node(opr, false); }
135 
136   void emit_move(LIR_Opr src, LIR_Opr dest);
137   void move_to_temp(LIR_Opr src);
138   void move_temp_to(LIR_Opr dest);
139   void move(ResolveNode* src, ResolveNode* dest);
140 
141   LIRGenerator* gen() {
142     return _gen;
143   }
144 
145  public:
146   PhiResolver(LIRGenerator* _lir_gen);
147   ~PhiResolver();
148 
149   void move(LIR_Opr src, LIR_Opr dest);
150 };
151 
152 
153 // only the classes below belong in the same file
154 class LIRGenerator: public InstructionVisitor, public BlockClosure {
155  // LIRGenerator should never get instatiated on the heap.
156  private:
157   void* operator new(size_t size) throw();
158   void* operator new[](size_t size) throw();
159   void operator delete(void* p) { ShouldNotReachHere(); }
160   void operator delete[](void* p) { ShouldNotReachHere(); }
161 
162   Compilation*  _compilation;
163   ciMethod*     _method;    // method that we are compiling
164   PhiResolverState  _resolver_state;
165   BlockBegin*   _block;
166   int           _virtual_register_number;
167 #ifdef ASSERT
168   Values        _instruction_for_operand;
169 #endif
170   BitMap2D      _vreg_flags; // flags which can be set on a per-vreg basis
171   LIR_List*     _lir;
172 
173   LIRGenerator* gen() {
174     return this;
175   }
176 
177   void print_if_not_loaded(const NewInstance* new_instance) PRODUCT_RETURN;
178 
179  public:
180 #ifdef ASSERT
181   LIR_List* lir(const char * file, int line) const {
182     _lir->set_file_and_line(file, line);
183     return _lir;
184   }
185 #endif
186   LIR_List* lir() const {
187     return _lir;
188   }
189 
190  private:
191   // a simple cache of constants used within a block
192   GrowableArray<LIR_Const*>       _constants;
193   LIR_OprList                     _reg_for_constants;
194   Values                          _unpinned_constants;
195 
196   friend class PhiResolver;
197 
198  public:
199   // unified bailout support
200   void bailout(const char* msg) const            { compilation()->bailout(msg); }
201   bool bailed_out() const                        { return compilation()->bailed_out(); }
202 
203   void block_do_prolog(BlockBegin* block);
204   void block_do_epilog(BlockBegin* block);
205 
206   // register allocation
207   LIR_Opr rlock(Value instr);                      // lock a free register
208   LIR_Opr rlock_result(Value instr);
209   LIR_Opr rlock_result(Value instr, BasicType type);
210   LIR_Opr rlock_byte(BasicType type);
211   LIR_Opr rlock_callee_saved(BasicType type);
212 
213   // get a constant into a register and get track of what register was used
214   LIR_Opr load_constant(Constant* x);
215   LIR_Opr load_constant(LIR_Const* constant);
216 
217   // Given an immediate value, return an operand usable in logical ops.
218   LIR_Opr load_immediate(jlong x, BasicType type);
219 
220   void  set_result(Value x, LIR_Opr opr)           {
221     assert(opr->is_valid(), "must set to valid value");
222     assert(x->operand()->is_illegal(), "operand should never change");
223     assert(!opr->is_register() || opr->is_virtual(), "should never set result to a physical register");
224     x->set_operand(opr);
225     assert(opr == x->operand(), "must be");
226 #ifdef ASSERT
227     if (opr->is_virtual()) {
228       _instruction_for_operand.at_put_grow(opr->vreg_number(), x, nullptr);
229     }
230 #endif
231   }
232   void  set_no_result(Value x)                     { assert(!x->has_uses(), "can't have use"); x->clear_operand(); }
233 
234   friend class LIRItem;
235 
236   LIR_Opr force_to_spill(LIR_Opr value, BasicType t);
237 
238   PhiResolverState& resolver_state() { return _resolver_state; }
239 
240   void  move_to_phi(PhiResolver* resolver, Value cur_val, Value sux_val);
241   void  move_to_phi(ValueStack* cur_state);
242 
243   void load_klass(LIR_Opr obj, LIR_Opr klass, CodeEmitInfo* null_check_info);
244 
245   // platform dependent
246   LIR_Opr getThreadPointer();
247 
248  private:
249   // code emission
250   void do_ArithmeticOp_Long(ArithmeticOp* x);
251   void do_ArithmeticOp_Int (ArithmeticOp* x);
252   void do_ArithmeticOp_FPU (ArithmeticOp* x);
253 
254   void do_RegisterFinalizer(Intrinsic* x);
255   void do_isInstance(Intrinsic* x);
256   void do_getClass(Intrinsic* x);
257   void do_getObjectSize(Intrinsic* x);
258   void do_currentCarrierThread(Intrinsic* x);
259   void do_scopedValueCache(Intrinsic* x);
260   void do_vthread(Intrinsic* x);
261   void do_JavaThreadField(Intrinsic* x, ByteSize offset);
262   void do_sizeOf(Intrinsic* x);
263   void do_addressOf(Intrinsic* x);
264   void do_FmaIntrinsic(Intrinsic* x);
265   void do_MathIntrinsic(Intrinsic* x);
266   void do_LibmIntrinsic(Intrinsic* x);
267   void do_ArrayCopy(Intrinsic* x);
268   void do_CompareAndSwap(Intrinsic* x, ValueType* type);
269   void do_PreconditionsCheckIndex(Intrinsic* x, BasicType type);
270   void do_FPIntrinsics(Intrinsic* x);
271   void do_Reference_get0(Intrinsic* x);
272   void do_update_CRC32(Intrinsic* x);
273   void do_update_CRC32C(Intrinsic* x);
274   void do_vectorizedMismatch(Intrinsic* x);
275   void do_blackhole(Intrinsic* x);
276 
277  public:
278   LIR_Opr call_runtime(BasicTypeArray* signature, LIRItemList* args, address entry, ValueType* result_type, CodeEmitInfo* info);
279   LIR_Opr call_runtime(BasicTypeArray* signature, LIR_OprList* args, address entry, ValueType* result_type, CodeEmitInfo* info);
280 
281   // convenience functions
282   LIR_Opr call_runtime(Value arg1, address entry, ValueType* result_type, CodeEmitInfo* info);
283   LIR_Opr call_runtime(Value arg1, Value arg2, address entry, ValueType* result_type, CodeEmitInfo* info);
284 
285   // Access API
286 
287  private:
288   BarrierSetC1 *_barrier_set;
289 
290  public:
291   void access_store_at(DecoratorSet decorators, BasicType type,
292                        LIRItem& base, LIR_Opr offset, LIR_Opr value,
293                        CodeEmitInfo* patch_info = nullptr, CodeEmitInfo* store_emit_info = nullptr);
294 
295   void access_load_at(DecoratorSet decorators, BasicType type,
296                       LIRItem& base, LIR_Opr offset, LIR_Opr result,
297                       CodeEmitInfo* patch_info = nullptr, CodeEmitInfo* load_emit_info = nullptr);
298 
299   void access_load(DecoratorSet decorators, BasicType type,
300                    LIR_Opr addr, LIR_Opr result);
301 
302   LIR_Opr access_atomic_cmpxchg_at(DecoratorSet decorators, BasicType type,
303                                    LIRItem& base, LIRItem& offset, LIRItem& cmp_value, LIRItem& new_value);
304 
305   LIR_Opr access_atomic_xchg_at(DecoratorSet decorators, BasicType type,
306                                 LIRItem& base, LIRItem& offset, LIRItem& value);
307 
308   LIR_Opr access_atomic_add_at(DecoratorSet decorators, BasicType type,
309                                LIRItem& base, LIRItem& offset, LIRItem& value);
310 
311   // These need to guarantee JMM volatile semantics are preserved on each platform
312   // and requires one implementation per architecture.
313   LIR_Opr atomic_cmpxchg(BasicType type, LIR_Opr addr, LIRItem& cmp_value, LIRItem& new_value);
314   LIR_Opr atomic_xchg(BasicType type, LIR_Opr addr, LIRItem& new_value);
315   LIR_Opr atomic_add(BasicType type, LIR_Opr addr, LIRItem& new_value);
316 
317 #ifdef CARDTABLEBARRIERSET_POST_BARRIER_HELPER
318   virtual void CardTableBarrierSet_post_barrier_helper(LIR_Opr addr, LIR_Const* card_table_base);
319 #endif
320 
321   // specific implementations
322   void array_store_check(LIR_Opr value, LIR_Opr array, CodeEmitInfo* store_check_info, ciMethod* profiled_method, int profiled_bci);
323 
324   static LIR_Opr result_register_for(ValueType* type, bool callee = false);
325 
326   ciObject* get_jobject_constant(Value value);
327 
328   LIRItemList* invoke_visit_arguments(Invoke* x);
329   void invoke_load_arguments(Invoke* x, LIRItemList* args, const LIR_OprList* arg_list);
330 
331   void trace_block_entry(BlockBegin* block);
332 
333   // volatile field operations are never patchable because a klass
334   // must be loaded to know it's volatile which means that the offset
335   // it always known as well.
336   void volatile_field_store(LIR_Opr value, LIR_Address* address, CodeEmitInfo* info);
337   void volatile_field_load(LIR_Address* address, LIR_Opr result, CodeEmitInfo* info);
338 
339   void put_Object_unsafe(LIR_Opr src, LIR_Opr offset, LIR_Opr data, BasicType type, bool is_volatile);
340   void get_Object_unsafe(LIR_Opr dest, LIR_Opr src, LIR_Opr offset, BasicType type, bool is_volatile);
341 
342   void arithmetic_call_op (Bytecodes::Code code, LIR_Opr result, LIR_OprList* args);
343 
344   void increment_counter(address counter, BasicType type, int step = 1);
345   void increment_counter(LIR_Address* addr, int step = 1);
346 
347   void arithmetic_op(Bytecodes::Code code, LIR_Opr result, LIR_Opr left, LIR_Opr right, LIR_Opr tmp, CodeEmitInfo* info = nullptr);
348   // machine dependent.  returns true if it emitted code for the multiply
349   bool strength_reduce_multiply(LIR_Opr left, jint constant, LIR_Opr result, LIR_Opr tmp);
350 
351   void store_stack_parameter (LIR_Opr opr, ByteSize offset_from_sp_in_bytes);
352 
353   void klass2reg_with_patching(LIR_Opr r, ciMetadata* obj, CodeEmitInfo* info, bool need_resolve = false);
354 
355   // this loads the length and compares against the index
356   void array_range_check          (LIR_Opr array, LIR_Opr index, CodeEmitInfo* null_check_info, CodeEmitInfo* range_check_info);
357 
358   void arithmetic_op_int  (Bytecodes::Code code, LIR_Opr result, LIR_Opr left, LIR_Opr right, LIR_Opr tmp);
359   void arithmetic_op_long (Bytecodes::Code code, LIR_Opr result, LIR_Opr left, LIR_Opr right, CodeEmitInfo* info = nullptr);
360   void arithmetic_op_fpu  (Bytecodes::Code code, LIR_Opr result, LIR_Opr left, LIR_Opr right, LIR_Opr tmp = LIR_OprFact::illegalOpr);
361 
362   void shift_op   (Bytecodes::Code code, LIR_Opr dst_reg, LIR_Opr value, LIR_Opr count, LIR_Opr tmp);
363 
364   void logic_op   (Bytecodes::Code code, LIR_Opr dst_reg, LIR_Opr left, LIR_Opr right);
365 
366   void monitor_enter (LIR_Opr object, LIR_Opr lock, LIR_Opr hdr, LIR_Opr scratch, int monitor_no, CodeEmitInfo* info_for_exception, CodeEmitInfo* info);
367   void monitor_exit  (LIR_Opr object, LIR_Opr lock, LIR_Opr hdr, LIR_Opr scratch, int monitor_no);
368 
369   void new_instance    (LIR_Opr  dst, ciInstanceKlass* klass, bool is_unresolved, LIR_Opr  scratch1, LIR_Opr  scratch2, LIR_Opr  scratch3,  LIR_Opr scratch4, LIR_Opr  klass_reg, CodeEmitInfo* info);
370 
371   // machine dependent
372   void cmp_mem_int(LIR_Condition condition, LIR_Opr base, int disp, int c, CodeEmitInfo* info);
373   void cmp_reg_mem(LIR_Condition condition, LIR_Opr reg, LIR_Opr base, int disp, BasicType type, CodeEmitInfo* info);
374 
375   void arraycopy_helper(Intrinsic* x, int* flags, ciArrayKlass** expected_type);
376 
377   // returns a LIR_Address to address an array location.  May also
378   // emit some code as part of address calculation.  If
379   // needs_card_mark is true then compute the full address for use by
380   // both the store and the card mark.
381   LIR_Address* generate_address(LIR_Opr base,
382                                 LIR_Opr index, int shift,
383                                 int disp,
384                                 BasicType type);
385   LIR_Address* generate_address(LIR_Opr base, int disp, BasicType type) {
386     return generate_address(base, LIR_OprFact::illegalOpr, 0, disp, type);
387   }
388   LIR_Address* emit_array_address(LIR_Opr array_opr, LIR_Opr index_opr, BasicType type);
389 
390   // the helper for generate_address
391   void add_large_constant(LIR_Opr src, int c, LIR_Opr dest);
392 
393   // machine preferences and characteristics
394   bool can_inline_as_constant(Value i S390_ONLY(COMMA int bits = 20)) const;
395   bool can_inline_as_constant(LIR_Const* c) const;
396   bool can_store_as_constant(Value i, BasicType type) const;
397 
398   LIR_Opr safepoint_poll_register();
399 
400   void profile_branch(If* if_instr, If::Condition cond);
401   void increment_event_counter_impl(CodeEmitInfo* info,
402                                     ciMethod *method, LIR_Opr step, int frequency,
403                                     int bci, bool backedge, bool notify);
404   void increment_event_counter(CodeEmitInfo* info, LIR_Opr step, int bci, bool backedge);
405   void increment_invocation_counter(CodeEmitInfo *info) {
406     if (compilation()->is_profiling()) {
407       increment_event_counter(info, LIR_OprFact::intConst(InvocationCounter::count_increment), InvocationEntryBci, false);
408     }
409   }
410   void increment_backedge_counter(CodeEmitInfo* info, int bci) {
411     if (compilation()->is_profiling()) {
412       increment_event_counter(info, LIR_OprFact::intConst(InvocationCounter::count_increment), bci, true);
413     }
414   }
415   void increment_backedge_counter_conditionally(LIR_Condition cond, LIR_Opr left, LIR_Opr right, CodeEmitInfo* info, int left_bci, int right_bci, int bci);
416   void increment_backedge_counter(CodeEmitInfo* info, LIR_Opr step, int bci) {
417     if (compilation()->is_profiling()) {
418       increment_event_counter(info, step, bci, true);
419     }
420   }
421   CodeEmitInfo* state_for(Instruction* x, ValueStack* state, bool ignore_xhandler = false);
422   CodeEmitInfo* state_for(Instruction* x);
423 
424   // allocates a virtual register for this instruction if
425   // one isn't already allocated.  Only for Phi and Local.
426   LIR_Opr operand_for_instruction(Instruction *x);
427 
428   void set_block(BlockBegin* block)              { _block = block; }
429 
430   void block_prolog(BlockBegin* block);
431   void block_epilog(BlockBegin* block);
432 
433   void do_root (Instruction* instr);
434   void walk    (Instruction* instr);
435 
436   LIR_Opr new_register(BasicType type);
437   LIR_Opr new_register(Value value)              { return new_register(as_BasicType(value->type())); }
438   LIR_Opr new_register(ValueType* type)          { return new_register(as_BasicType(type)); }
439 
440   // returns a register suitable for doing pointer math
441   LIR_Opr new_pointer_register() {
442 #ifdef _LP64
443     return new_register(T_LONG);
444 #else
445     return new_register(T_INT);
446 #endif
447   }
448 
449   static LIR_Condition lir_cond(If::Condition cond) {
450     LIR_Condition l = lir_cond_unknown;
451     switch (cond) {
452     case If::eql: l = lir_cond_equal;        break;
453     case If::neq: l = lir_cond_notEqual;     break;
454     case If::lss: l = lir_cond_less;         break;
455     case If::leq: l = lir_cond_lessEqual;    break;
456     case If::geq: l = lir_cond_greaterEqual; break;
457     case If::gtr: l = lir_cond_greater;      break;
458     case If::aeq: l = lir_cond_aboveEqual;   break;
459     case If::beq: l = lir_cond_belowEqual;   break;
460     default: fatal("You must pass valid If::Condition");
461     };
462     return l;
463   }
464 
465 #ifdef __SOFTFP__
466   void do_soft_float_compare(If *x);
467 #endif // __SOFTFP__
468 
469   SwitchRangeArray* create_lookup_ranges(TableSwitch* x);
470   SwitchRangeArray* create_lookup_ranges(LookupSwitch* x);
471   void do_SwitchRanges(SwitchRangeArray* x, LIR_Opr value, BlockBegin* default_sux);
472 
473   void do_RuntimeCall(address routine, Intrinsic* x);
474 
475   ciKlass* profile_type(ciMethodData* md, int md_first_offset, int md_offset, intptr_t profiled_k,
476                         Value arg, LIR_Opr& mdp, bool not_null, ciKlass* signature_at_call_k,
477                         ciKlass* callee_signature_k);
478   void profile_arguments(ProfileCall* x);
479   void profile_parameters(Base* x);
480   void profile_parameters_at_call(ProfileCall* x);
481   LIR_Opr mask_boolean(LIR_Opr array, LIR_Opr value, CodeEmitInfo*& null_check_info);
482 
483   void do_sizeOf_impl(Intrinsic* x, int arg_idx);
484 
485  public:
486   Compilation*  compilation() const              { return _compilation; }
487   FrameMap*     frame_map() const                { return _compilation->frame_map(); }
488   ciMethod*     method() const                   { return _method; }
489   BlockBegin*   block() const                    { return _block; }
490   IRScope*      scope() const                    { return block()->scope(); }
491 
492   int max_virtual_register_number() const        { return _virtual_register_number; }
493 
494   void block_do(BlockBegin* block);
495 
496   // Flags that can be set on vregs
497   enum VregFlag {
498       must_start_in_memory = 0  // needs to be assigned a memory location at beginning, but may then be loaded in a register
499     , callee_saved     = 1    // must be in a callee saved register
500     , byte_reg         = 2    // must be in a byte register
501     , num_vreg_flags
502 
503   };
504 
505   LIRGenerator(Compilation* compilation, ciMethod* method)
506     : _compilation(compilation)
507     , _method(method)
508     , _virtual_register_number(LIR_Opr::vreg_base)
509     , _vreg_flags(num_vreg_flags)
510     , _barrier_set(BarrierSet::barrier_set()->barrier_set_c1()) {
511   }
512 
513 #ifdef ASSERT
514   // for virtual registers, maps them back to Phi's or Local's
515   Instruction* instruction_for_vreg(int reg_num);
516 #endif
517 
518   void set_vreg_flag   (int vreg_num, VregFlag f);
519   bool is_vreg_flag_set(int vreg_num, VregFlag f);
520   void set_vreg_flag   (LIR_Opr opr,  VregFlag f) { set_vreg_flag(opr->vreg_number(), f); }
521   bool is_vreg_flag_set(LIR_Opr opr,  VregFlag f) { return is_vreg_flag_set(opr->vreg_number(), f); }
522 
523   // statics
524   static LIR_Opr exceptionOopOpr();
525   static LIR_Opr exceptionPcOpr();
526   static LIR_Opr divInOpr();
527   static LIR_Opr divOutOpr();
528   static LIR_Opr remOutOpr();
529 #ifdef S390
530   // On S390 we can do ldiv, lrem without RT call.
531   static LIR_Opr ldivInOpr();
532   static LIR_Opr ldivOutOpr();
533   static LIR_Opr lremOutOpr();
534 #endif
535   static LIR_Opr shiftCountOpr();
536   LIR_Opr syncLockOpr();
537   LIR_Opr syncTempOpr();
538   LIR_Opr atomicLockOpr();
539 
540   // Intrinsic for Class::isInstance
541   address isInstance_entry();
542 
543   // returns a register suitable for saving the thread in a
544   // call_runtime_leaf if one is needed.
545   LIR_Opr getThreadTemp();
546 
547   // visitor functionality
548   virtual void do_Phi            (Phi*             x);
549   virtual void do_Local          (Local*           x);
550   virtual void do_Constant       (Constant*        x);
551   virtual void do_LoadField      (LoadField*       x);
552   virtual void do_StoreField     (StoreField*      x);
553   virtual void do_ArrayLength    (ArrayLength*     x);
554   virtual void do_LoadIndexed    (LoadIndexed*     x);
555   virtual void do_StoreIndexed   (StoreIndexed*    x);
556   virtual void do_NegateOp       (NegateOp*        x);
557   virtual void do_ArithmeticOp   (ArithmeticOp*    x);
558   virtual void do_ShiftOp        (ShiftOp*         x);
559   virtual void do_LogicOp        (LogicOp*         x);
560   virtual void do_CompareOp      (CompareOp*       x);
561   virtual void do_IfOp           (IfOp*            x);
562   virtual void do_Convert        (Convert*         x);
563   virtual void do_NullCheck      (NullCheck*       x);
564   virtual void do_TypeCast       (TypeCast*        x);
565   virtual void do_Invoke         (Invoke*          x);
566   virtual void do_NewInstance    (NewInstance*     x);
567   virtual void do_NewTypeArray   (NewTypeArray*    x);
568   virtual void do_NewObjectArray (NewObjectArray*  x);
569   virtual void do_NewMultiArray  (NewMultiArray*   x);
570   virtual void do_CheckCast      (CheckCast*       x);
571   virtual void do_InstanceOf     (InstanceOf*      x);
572   virtual void do_MonitorEnter   (MonitorEnter*    x);
573   virtual void do_MonitorExit    (MonitorExit*     x);
574   virtual void do_Intrinsic      (Intrinsic*       x);
575   virtual void do_BlockBegin     (BlockBegin*      x);
576   virtual void do_Goto           (Goto*            x);
577   virtual void do_If             (If*              x);
578   virtual void do_TableSwitch    (TableSwitch*     x);
579   virtual void do_LookupSwitch   (LookupSwitch*    x);
580   virtual void do_Return         (Return*          x);
581   virtual void do_Throw          (Throw*           x);
582   virtual void do_Base           (Base*            x);
583   virtual void do_OsrEntry       (OsrEntry*        x);
584   virtual void do_ExceptionObject(ExceptionObject* x);
585   virtual void do_UnsafeGet      (UnsafeGet*       x);
586   virtual void do_UnsafePut      (UnsafePut*       x);
587   virtual void do_UnsafeGetAndSet(UnsafeGetAndSet* x);
588   virtual void do_ProfileCall    (ProfileCall*     x);
589   virtual void do_ProfileReturnType (ProfileReturnType* x);
590   virtual void do_ProfileInvoke  (ProfileInvoke*   x);
591   virtual void do_RuntimeCall    (RuntimeCall*     x);
592   virtual void do_MemBar         (MemBar*          x);
593   virtual void do_RangeCheckPredicate(RangeCheckPredicate* x);
594 #ifdef ASSERT
595   virtual void do_Assert         (Assert*          x);
596 #endif
597 
598 #ifdef C1_LIRGENERATOR_MD_HPP
599 #include C1_LIRGENERATOR_MD_HPP
600 #endif
601 };
602 
603 
604 class LIRItem: public CompilationResourceObj {
605  private:
606   Value         _value;
607   LIRGenerator* _gen;
608   LIR_Opr       _result;
609   bool          _destroys_register;
610   LIR_Opr       _new_result;
611 
612   LIRGenerator* gen() const { return _gen; }
613 
614  public:
615   LIRItem(Value value, LIRGenerator* gen) {
616     _destroys_register = false;
617     _gen = gen;
618     set_instruction(value);
619   }
620 
621   LIRItem(LIRGenerator* gen) {
622     _destroys_register = false;
623     _gen = gen;
624     _result = LIR_OprFact::illegalOpr;
625     set_instruction(nullptr);
626   }
627 
628   void set_instruction(Value value) {
629     _value = value;
630     _result = LIR_OprFact::illegalOpr;
631     if (_value != nullptr) {
632       _gen->walk(_value);
633       _result = _value->operand();
634     }
635     _new_result = LIR_OprFact::illegalOpr;
636   }
637 
638   Value value() const          { return _value;          }
639   ValueType* type() const      { return value()->type(); }
640   LIR_Opr result()             {
641     assert(!_destroys_register || (!_result->is_register() || _result->is_virtual()),
642            "shouldn't use set_destroys_register with physical registers");
643     if (_destroys_register && _result->is_register()) {
644       if (_new_result->is_illegal()) {
645         _new_result = _gen->new_register(type());
646         gen()->lir()->move(_result, _new_result);
647       }
648       return _new_result;
649     } else {
650       return _result;
651     }
652   }
653 
654   void set_result(LIR_Opr opr);
655 
656   void load_item();
657   void load_byte_item();
658   void load_nonconstant(S390_ONLY(int bits = 20));
659   // load any values which can't be expressed as part of a single store instruction
660   void load_for_store(BasicType store_type);
661   void load_item_force(LIR_Opr reg);
662 
663   void dont_load_item() {
664     // do nothing
665   }
666 
667   void set_destroys_register() {
668     _destroys_register = true;
669   }
670 
671   bool is_constant() const { return value()->as_Constant() != nullptr; }
672   bool is_stack()          { return result()->is_stack(); }
673   bool is_register()       { return result()->is_register(); }
674 
675   ciObject* get_jobject_constant() const;
676   jint      get_jint_constant() const;
677   jlong     get_jlong_constant() const;
678   jfloat    get_jfloat_constant() const;
679   jdouble   get_jdouble_constant() const;
680   jint      get_address_constant() const;
681 };
682 
683 #endif // SHARE_C1_C1_LIRGENERATOR_HPP