1 /*
  2  * Copyright (c) 2005, 2021, 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 "ci/ciMethodData.hpp"
 32 #include "gc/shared/barrierSet.hpp"
 33 #include "jfr/support/jfrIntrinsics.hpp"
 34 #include "utilities/macros.hpp"
 35 #include "utilities/sizes.hpp"
 36 
 37 class BarrierSetC1;
 38 
 39 // The classes responsible for code emission and register allocation
 40 
 41 
 42 class LIRGenerator;
 43 class LIREmitter;
 44 class Invoke;
 45 class LIRItem;
 46 
 47 typedef GrowableArray<LIRItem*> LIRItemList;
 48 
 49 class C1SwitchRange: public CompilationResourceObj {
 50  private:
 51   int _low_key;
 52   int _high_key;
 53   BlockBegin* _sux;
 54  public:
 55   C1SwitchRange(int start_key, BlockBegin* sux): _low_key(start_key), _high_key(start_key), _sux(sux) {}
 56   void set_high_key(int key) { _high_key = key; }
 57 
 58   int high_key() const { return _high_key; }
 59   int low_key() const { return _low_key; }
 60   BlockBegin* sux() const { return _sux; }
 61 };
 62 
 63 typedef GrowableArray<C1SwitchRange*> SwitchRangeArray;
 64 typedef GrowableArray<C1SwitchRange*> SwitchRangeList;
 65 
 66 class ResolveNode;
 67 
 68 typedef GrowableArray<ResolveNode*> NodeList;
 69 
 70 // Node objects form a directed graph of LIR_Opr
 71 // Edges between Nodes represent moves from one Node to its destinations
 72 class ResolveNode: public CompilationResourceObj {
 73  private:
 74   LIR_Opr    _operand;       // the source or destinaton
 75   NodeList   _destinations;  // for the operand
 76   bool       _assigned;      // Value assigned to this Node?
 77   bool       _visited;       // Node already visited?
 78   bool       _start_node;    // Start node already visited?
 79 
 80  public:
 81   ResolveNode(LIR_Opr operand)
 82     : _operand(operand)
 83     , _assigned(false)
 84     , _visited(false)
 85     , _start_node(false) {};
 86 
 87   // accessors
 88   LIR_Opr operand() const           { return _operand; }
 89   int no_of_destinations() const    { return _destinations.length(); }
 90   ResolveNode* destination_at(int i)     { return _destinations.at(i); }
 91   bool assigned() const             { return _assigned; }
 92   bool visited() const              { return _visited; }
 93   bool start_node() const           { return _start_node; }
 94 
 95   // modifiers
 96   void append(ResolveNode* dest)         { _destinations.append(dest); }
 97   void set_assigned()               { _assigned = true; }
 98   void set_visited()                { _visited = true; }
 99   void set_start_node()             { _start_node = true; }
100 };
101 
102 
103 // This is shared state to be used by the PhiResolver so the operand
104 // arrays don't have to be reallocated for each resolution.
105 class PhiResolverState: public CompilationResourceObj {
106   friend class PhiResolver;
107 
108  private:
109   NodeList _virtual_operands; // Nodes where the operand is a virtual register
110   NodeList _other_operands;   // Nodes where the operand is not a virtual register
111   NodeList _vreg_table;       // Mapping from virtual register to Node
112 
113  public:
114   PhiResolverState() {}
115 
116   void reset();
117 };
118 
119 
120 // class used to move value of phi operand to phi function
121 class PhiResolver: public CompilationResourceObj {
122  private:
123   LIRGenerator*     _gen;
124   PhiResolverState& _state; // temporary state cached by LIRGenerator
125 
126   ResolveNode*   _loop;
127   LIR_Opr _temp;
128 
129   // access to shared state arrays
130   NodeList& virtual_operands() { return _state._virtual_operands; }
131   NodeList& other_operands()   { return _state._other_operands;   }
132   NodeList& vreg_table()       { return _state._vreg_table;       }
133 
134   ResolveNode* create_node(LIR_Opr opr, bool source);
135   ResolveNode* source_node(LIR_Opr opr)      { return create_node(opr, true); }
136   ResolveNode* destination_node(LIR_Opr opr) { return create_node(opr, false); }
137 
138   void emit_move(LIR_Opr src, LIR_Opr dest);
139   void move_to_temp(LIR_Opr src);
140   void move_temp_to(LIR_Opr dest);
141   void move(ResolveNode* src, ResolveNode* dest);
142 
143   LIRGenerator* gen() {
144     return _gen;
145   }
146 
147  public:
148   PhiResolver(LIRGenerator* _lir_gen);
149   ~PhiResolver();
150 
151   void move(LIR_Opr src, LIR_Opr dest);
152 };
153 
154 
155 // only the classes below belong in the same file
156 class LIRGenerator: public InstructionVisitor, public BlockClosure {
157  // LIRGenerator should never get instatiated on the heap.
158  private:
159   void* operator new(size_t size) throw();
160   void* operator new[](size_t size) throw();
161   void operator delete(void* p) { ShouldNotReachHere(); }
162   void operator delete[](void* p) { ShouldNotReachHere(); }
163 
164   Compilation*  _compilation;
165   ciMethod*     _method;    // method that we are compiling
166   PhiResolverState  _resolver_state;
167   BlockBegin*   _block;
168   int           _virtual_register_number;
169   Values        _instruction_for_operand;
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(int 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     if (opr->is_virtual()) {
227       _instruction_for_operand.at_put_grow(opr->vreg_number(), x, NULL);
228     }
229   }
230   void  set_no_result(Value x)                     { assert(!x->has_uses(), "can't have use"); x->clear_operand(); }
231 
232   friend class LIRItem;
233 
234   LIR_Opr round_item(LIR_Opr opr);
235   LIR_Opr force_to_spill(LIR_Opr value, BasicType t);
236 
237   PhiResolverState& resolver_state() { return _resolver_state; }
238 
239   void  move_to_phi(PhiResolver* resolver, Value cur_val, Value sux_val);
240   void  move_to_phi(ValueStack* cur_state);
241 
242   void load_klass(LIR_Opr obj, LIR_Opr klass, CodeEmitInfo* null_check_info);
243 
244   // platform dependent
245   LIR_Opr getThreadPointer();
246 
247  private:
248   // code emission
249   void do_ArithmeticOp_Long(ArithmeticOp* x);
250   void do_ArithmeticOp_Int (ArithmeticOp* x);
251   void do_ArithmeticOp_FPU (ArithmeticOp* x);
252 
253   void do_RegisterFinalizer(Intrinsic* x);
254   void do_isInstance(Intrinsic* x);
255   void do_isPrimitive(Intrinsic* x);
256   void do_getModifiers(Intrinsic* x);
257   void do_getClass(Intrinsic* x);
258   void do_currentThread(Intrinsic* x);
259   void do_getObjectSize(Intrinsic* x);
260   void do_FmaIntrinsic(Intrinsic* x);
261   void do_MathIntrinsic(Intrinsic* x);
262   void do_LibmIntrinsic(Intrinsic* x);
263   void do_ArrayCopy(Intrinsic* x);
264   void do_CompareAndSwap(Intrinsic* x, ValueType* type);
265   void do_NIOCheckIndex(Intrinsic* x);
266   void do_FPIntrinsics(Intrinsic* x);
267   void do_Reference_get(Intrinsic* x);
268   void do_update_CRC32(Intrinsic* x);
269   void do_update_CRC32C(Intrinsic* x);
270   void do_vectorizedMismatch(Intrinsic* x);
271   void do_blackhole(Intrinsic* x);
272 
273  public:
274   LIR_Opr call_runtime(BasicTypeArray* signature, LIRItemList* args, address entry, ValueType* result_type, CodeEmitInfo* info);
275   LIR_Opr call_runtime(BasicTypeArray* signature, LIR_OprList* args, address entry, ValueType* result_type, CodeEmitInfo* info);
276 
277   // convenience functions
278   LIR_Opr call_runtime(Value arg1, address entry, ValueType* result_type, CodeEmitInfo* info);
279   LIR_Opr call_runtime(Value arg1, Value arg2, address entry, ValueType* result_type, CodeEmitInfo* info);
280 
281   // Access API
282 
283  private:
284   BarrierSetC1 *_barrier_set;
285 
286  public:
287   void access_store_at(DecoratorSet decorators, BasicType type,
288                        LIRItem& base, LIR_Opr offset, LIR_Opr value,
289                        CodeEmitInfo* patch_info = NULL, CodeEmitInfo* store_emit_info = NULL);
290 
291   void access_load_at(DecoratorSet decorators, BasicType type,
292                       LIRItem& base, LIR_Opr offset, LIR_Opr result,
293                       CodeEmitInfo* patch_info = NULL, CodeEmitInfo* load_emit_info = NULL);
294 
295   void access_load(DecoratorSet decorators, BasicType type,
296                    LIR_Opr addr, LIR_Opr result);
297 
298   LIR_Opr access_atomic_cmpxchg_at(DecoratorSet decorators, BasicType type,
299                                    LIRItem& base, LIRItem& offset, LIRItem& cmp_value, LIRItem& new_value);
300 
301   LIR_Opr access_atomic_xchg_at(DecoratorSet decorators, BasicType type,
302                                 LIRItem& base, LIRItem& offset, LIRItem& value);
303 
304   LIR_Opr access_atomic_add_at(DecoratorSet decorators, BasicType type,
305                                LIRItem& base, LIRItem& offset, LIRItem& value);
306 
307   // These need to guarantee JMM volatile semantics are preserved on each platform
308   // and requires one implementation per architecture.
309   LIR_Opr atomic_cmpxchg(BasicType type, LIR_Opr addr, LIRItem& cmp_value, LIRItem& new_value);
310   LIR_Opr atomic_xchg(BasicType type, LIR_Opr addr, LIRItem& new_value);
311   LIR_Opr atomic_add(BasicType type, LIR_Opr addr, LIRItem& new_value);
312 
313 #ifdef CARDTABLEBARRIERSET_POST_BARRIER_HELPER
314   virtual void CardTableBarrierSet_post_barrier_helper(LIR_OprDesc* addr, LIR_Const* card_table_base);
315 #endif
316 
317   // specific implementations
318   void array_store_check(LIR_Opr value, LIR_Opr array, CodeEmitInfo* store_check_info, ciMethod* profiled_method, int profiled_bci);
319 
320   static LIR_Opr result_register_for(ValueType* type, bool callee = false);
321 
322   ciObject* get_jobject_constant(Value value);
323 
324   LIRItemList* invoke_visit_arguments(Invoke* x);
325   void invoke_load_arguments(Invoke* x, LIRItemList* args, const LIR_OprList* arg_list);
326 
327   void trace_block_entry(BlockBegin* block);
328 
329   // volatile field operations are never patchable because a klass
330   // must be loaded to know it's volatile which means that the offset
331   // it always known as well.
332   void volatile_field_store(LIR_Opr value, LIR_Address* address, CodeEmitInfo* info);
333   void volatile_field_load(LIR_Address* address, LIR_Opr result, CodeEmitInfo* info);
334 
335   void put_Object_unsafe(LIR_Opr src, LIR_Opr offset, LIR_Opr data, BasicType type, bool is_volatile);
336   void get_Object_unsafe(LIR_Opr dest, LIR_Opr src, LIR_Opr offset, BasicType type, bool is_volatile);
337 
338   void arithmetic_call_op (Bytecodes::Code code, LIR_Opr result, LIR_OprList* args);
339 
340   void increment_counter(address counter, BasicType type, int step = 1);
341   void increment_counter(LIR_Address* addr, int step = 1);
342 
343   void arithmetic_op(Bytecodes::Code code, LIR_Opr result, LIR_Opr left, LIR_Opr right, LIR_Opr tmp, CodeEmitInfo* info = NULL);
344   // machine dependent.  returns true if it emitted code for the multiply
345   bool strength_reduce_multiply(LIR_Opr left, jint constant, LIR_Opr result, LIR_Opr tmp);
346 
347   void store_stack_parameter (LIR_Opr opr, ByteSize offset_from_sp_in_bytes);
348 
349   void klass2reg_with_patching(LIR_Opr r, ciMetadata* obj, CodeEmitInfo* info, bool need_resolve = false);
350 
351   // this loads the length and compares against the index
352   void array_range_check          (LIR_Opr array, LIR_Opr index, CodeEmitInfo* null_check_info, CodeEmitInfo* range_check_info);
353   // For java.nio.Buffer.checkIndex
354   void nio_range_check            (LIR_Opr buffer, LIR_Opr index, LIR_Opr result, CodeEmitInfo* info);
355 
356   void arithmetic_op_int  (Bytecodes::Code code, LIR_Opr result, LIR_Opr left, LIR_Opr right, LIR_Opr tmp);
357   void arithmetic_op_long (Bytecodes::Code code, LIR_Opr result, LIR_Opr left, LIR_Opr right, CodeEmitInfo* info = NULL);
358   void arithmetic_op_fpu  (Bytecodes::Code code, LIR_Opr result, LIR_Opr left, LIR_Opr right, LIR_Opr tmp = LIR_OprFact::illegalOpr);
359 
360   void shift_op   (Bytecodes::Code code, LIR_Opr dst_reg, LIR_Opr value, LIR_Opr count, LIR_Opr tmp);
361 
362   void logic_op   (Bytecodes::Code code, LIR_Opr dst_reg, LIR_Opr left, LIR_Opr right);
363 
364   void monitor_enter (LIR_Opr object, LIR_Opr lock, LIR_Opr hdr, LIR_Opr scratch, int monitor_no, CodeEmitInfo* info_for_exception, CodeEmitInfo* info);
365   void monitor_exit  (LIR_Opr object, LIR_Opr lock, LIR_Opr hdr, LIR_Opr scratch, int monitor_no);
366 
367   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);
368 
369   // machine dependent
370   void cmp_mem_int(LIR_Condition condition, LIR_Opr base, int disp, int c, CodeEmitInfo* info);
371   void cmp_reg_mem(LIR_Condition condition, LIR_Opr reg, LIR_Opr base, int disp, BasicType type, CodeEmitInfo* info);
372 
373   void arraycopy_helper(Intrinsic* x, int* flags, ciArrayKlass** expected_type);
374 
375   // returns a LIR_Address to address an array location.  May also
376   // emit some code as part of address calculation.  If
377   // needs_card_mark is true then compute the full address for use by
378   // both the store and the card mark.
379   LIR_Address* generate_address(LIR_Opr base,
380                                 LIR_Opr index, int shift,
381                                 int disp,
382                                 BasicType type);
383   LIR_Address* generate_address(LIR_Opr base, int disp, BasicType type) {
384     return generate_address(base, LIR_OprFact::illegalOpr, 0, disp, type);
385   }
386   LIR_Address* emit_array_address(LIR_Opr array_opr, LIR_Opr index_opr, BasicType type);
387 
388   // the helper for generate_address
389   void add_large_constant(LIR_Opr src, int c, LIR_Opr dest);
390 
391   // machine preferences and characteristics
392   bool can_inline_as_constant(Value i S390_ONLY(COMMA int bits = 20)) const;
393   bool can_inline_as_constant(LIR_Const* c) const;
394   bool can_store_as_constant(Value i, BasicType type) const;
395 
396   LIR_Opr safepoint_poll_register();
397 
398   void profile_branch(If* if_instr, If::Condition cond);
399   void increment_event_counter_impl(CodeEmitInfo* info,
400                                     ciMethod *method, LIR_Opr step, int frequency,
401                                     int bci, bool backedge, bool notify);
402   void increment_event_counter(CodeEmitInfo* info, LIR_Opr step, int bci, bool backedge);
403   void increment_invocation_counter(CodeEmitInfo *info) {
404     if (compilation()->count_invocations()) {
405       increment_event_counter(info, LIR_OprFact::intConst(InvocationCounter::count_increment), InvocationEntryBci, false);
406     }
407   }
408   void increment_backedge_counter(CodeEmitInfo* info, int bci) {
409     if (compilation()->count_backedges()) {
410       increment_event_counter(info, LIR_OprFact::intConst(InvocationCounter::count_increment), bci, true);
411     }
412   }
413   void increment_backedge_counter_conditionally(LIR_Condition cond, LIR_Opr left, LIR_Opr right, CodeEmitInfo* info, int left_bci, int right_bci, int bci);
414   void increment_backedge_counter(CodeEmitInfo* info, LIR_Opr step, int bci) {
415     if (compilation()->count_backedges()) {
416       increment_event_counter(info, step, bci, true);
417     }
418   }
419   void decrement_age(CodeEmitInfo* info);
420   CodeEmitInfo* state_for(Instruction* x, ValueStack* state, bool ignore_xhandler = false);
421   CodeEmitInfo* state_for(Instruction* x);
422 
423   // allocates a virtual register for this instruction if
424   // one isn't already allocated.  Only for Phi and Local.
425   LIR_Opr operand_for_instruction(Instruction *x);
426 
427   void set_block(BlockBegin* block)              { _block = block; }
428 
429   void block_prolog(BlockBegin* block);
430   void block_epilog(BlockBegin* block);
431 
432   void do_root (Instruction* instr);
433   void walk    (Instruction* instr);
434 
435   void bind_block_entry(BlockBegin* block);
436   void start_block(BlockBegin* block);
437 
438   LIR_Opr new_register(BasicType type);
439   LIR_Opr new_register(Value value)              { return new_register(as_BasicType(value->type())); }
440   LIR_Opr new_register(ValueType* type)          { return new_register(as_BasicType(type)); }
441 
442   // returns a register suitable for doing pointer math
443   LIR_Opr new_pointer_register() {
444 #ifdef _LP64
445     return new_register(T_LONG);
446 #else
447     return new_register(T_INT);
448 #endif
449   }
450 
451   static LIR_Condition lir_cond(If::Condition cond) {
452     LIR_Condition l = lir_cond_unknown;
453     switch (cond) {
454     case If::eql: l = lir_cond_equal;        break;
455     case If::neq: l = lir_cond_notEqual;     break;
456     case If::lss: l = lir_cond_less;         break;
457     case If::leq: l = lir_cond_lessEqual;    break;
458     case If::geq: l = lir_cond_greaterEqual; break;
459     case If::gtr: l = lir_cond_greater;      break;
460     case If::aeq: l = lir_cond_aboveEqual;   break;
461     case If::beq: l = lir_cond_belowEqual;   break;
462     default: fatal("You must pass valid If::Condition");
463     };
464     return l;
465   }
466 
467 #ifdef __SOFTFP__
468   void do_soft_float_compare(If *x);
469 #endif // __SOFTFP__
470 
471   SwitchRangeArray* create_lookup_ranges(TableSwitch* x);
472   SwitchRangeArray* create_lookup_ranges(LookupSwitch* x);
473   void do_SwitchRanges(SwitchRangeArray* x, LIR_Opr value, BlockBegin* default_sux);
474 
475 #ifdef JFR_HAVE_INTRINSICS
476   void do_ClassIDIntrinsic(Intrinsic* x);
477   void do_getEventWriter(Intrinsic* x);
478 #endif
479 
480   void do_RuntimeCall(address routine, Intrinsic* x);
481 
482   ciKlass* profile_type(ciMethodData* md, int md_first_offset, int md_offset, intptr_t profiled_k,
483                         Value arg, LIR_Opr& mdp, bool not_null, ciKlass* signature_at_call_k,
484                         ciKlass* callee_signature_k);
485   void profile_arguments(ProfileCall* x);
486   void profile_parameters(Base* x);
487   void profile_parameters_at_call(ProfileCall* x);
488   LIR_Opr mask_boolean(LIR_Opr array, LIR_Opr value, CodeEmitInfo*& null_check_info);
489   LIR_Opr maybe_mask_boolean(StoreIndexed* x, LIR_Opr array, LIR_Opr value, CodeEmitInfo*& null_check_info);
490 
491  public:
492   Compilation*  compilation() const              { return _compilation; }
493   FrameMap*     frame_map() const                { return _compilation->frame_map(); }
494   ciMethod*     method() const                   { return _method; }
495   BlockBegin*   block() const                    { return _block; }
496   IRScope*      scope() const                    { return block()->scope(); }
497 
498   int max_virtual_register_number() const        { return _virtual_register_number; }
499 
500   void block_do(BlockBegin* block);
501 
502   // Flags that can be set on vregs
503   enum VregFlag {
504       must_start_in_memory = 0  // needs to be assigned a memory location at beginning, but may then be loaded in a register
505     , callee_saved     = 1    // must be in a callee saved register
506     , byte_reg         = 2    // must be in a byte register
507     , num_vreg_flags
508 
509   };
510 
511   LIRGenerator(Compilation* compilation, ciMethod* method)
512     : _compilation(compilation)
513     , _method(method)
514     , _virtual_register_number(LIR_OprDesc::vreg_base)
515     , _vreg_flags(num_vreg_flags)
516     , _barrier_set(BarrierSet::barrier_set()->barrier_set_c1()) {
517   }
518 
519   // for virtual registers, maps them back to Phi's or Local's
520   Instruction* instruction_for_opr(LIR_Opr opr);
521   Instruction* instruction_for_vreg(int reg_num);
522 
523   void set_vreg_flag   (int vreg_num, VregFlag f);
524   bool is_vreg_flag_set(int vreg_num, VregFlag f);
525   void set_vreg_flag   (LIR_Opr opr,  VregFlag f) { set_vreg_flag(opr->vreg_number(), f); }
526   bool is_vreg_flag_set(LIR_Opr opr,  VregFlag f) { return is_vreg_flag_set(opr->vreg_number(), f); }
527 
528   // statics
529   static LIR_Opr exceptionOopOpr();
530   static LIR_Opr exceptionPcOpr();
531   static LIR_Opr divInOpr();
532   static LIR_Opr divOutOpr();
533   static LIR_Opr remOutOpr();
534 #ifdef S390
535   // On S390 we can do ldiv, lrem without RT call.
536   static LIR_Opr ldivInOpr();
537   static LIR_Opr ldivOutOpr();
538   static LIR_Opr lremOutOpr();
539 #endif
540   static LIR_Opr shiftCountOpr();
541   LIR_Opr syncLockOpr();
542   LIR_Opr syncTempOpr();
543   LIR_Opr atomicLockOpr();
544 
545   // returns a register suitable for saving the thread in a
546   // call_runtime_leaf if one is needed.
547   LIR_Opr getThreadTemp();
548 
549   // visitor functionality
550   virtual void do_Phi            (Phi*             x);
551   virtual void do_Local          (Local*           x);
552   virtual void do_Constant       (Constant*        x);
553   virtual void do_LoadField      (LoadField*       x);
554   virtual void do_StoreField     (StoreField*      x);
555   virtual void do_ArrayLength    (ArrayLength*     x);
556   virtual void do_LoadIndexed    (LoadIndexed*     x);
557   virtual void do_StoreIndexed   (StoreIndexed*    x);
558   virtual void do_NegateOp       (NegateOp*        x);
559   virtual void do_ArithmeticOp   (ArithmeticOp*    x);
560   virtual void do_ShiftOp        (ShiftOp*         x);
561   virtual void do_LogicOp        (LogicOp*         x);
562   virtual void do_CompareOp      (CompareOp*       x);
563   virtual void do_IfOp           (IfOp*            x);
564   virtual void do_Convert        (Convert*         x);
565   virtual void do_NullCheck      (NullCheck*       x);
566   virtual void do_TypeCast       (TypeCast*        x);
567   virtual void do_Invoke         (Invoke*          x);
568   virtual void do_NewInstance    (NewInstance*     x);
569   virtual void do_NewTypeArray   (NewTypeArray*    x);
570   virtual void do_NewObjectArray (NewObjectArray*  x);
571   virtual void do_NewMultiArray  (NewMultiArray*   x);
572   virtual void do_CheckCast      (CheckCast*       x);
573   virtual void do_InstanceOf     (InstanceOf*      x);
574   virtual void do_MonitorEnter   (MonitorEnter*    x);
575   virtual void do_MonitorExit    (MonitorExit*     x);
576   virtual void do_Intrinsic      (Intrinsic*       x);
577   virtual void do_BlockBegin     (BlockBegin*      x);
578   virtual void do_Goto           (Goto*            x);
579   virtual void do_If             (If*              x);
580   virtual void do_TableSwitch    (TableSwitch*     x);
581   virtual void do_LookupSwitch   (LookupSwitch*    x);
582   virtual void do_Return         (Return*          x);
583   virtual void do_Throw          (Throw*           x);
584   virtual void do_Base           (Base*            x);
585   virtual void do_OsrEntry       (OsrEntry*        x);
586   virtual void do_ExceptionObject(ExceptionObject* x);
587   virtual void do_RoundFP        (RoundFP*         x);
588   virtual void do_UnsafeGetRaw   (UnsafeGetRaw*    x);
589   virtual void do_UnsafePutRaw   (UnsafePutRaw*    x);
590   virtual void do_UnsafeGetObject(UnsafeGetObject* x);
591   virtual void do_UnsafePutObject(UnsafePutObject* x);
592   virtual void do_UnsafeGetAndSetObject(UnsafeGetAndSetObject* x);
593   virtual void do_ProfileCall    (ProfileCall*     x);
594   virtual void do_ProfileReturnType (ProfileReturnType* x);
595   virtual void do_ProfileInvoke  (ProfileInvoke*   x);
596   virtual void do_RuntimeCall    (RuntimeCall*     x);
597   virtual void do_MemBar         (MemBar*          x);
598   virtual void do_RangeCheckPredicate(RangeCheckPredicate* x);
599 #ifdef ASSERT
600   virtual void do_Assert         (Assert*          x);
601 #endif
602 
603 #ifdef C1_LIRGENERATOR_MD_HPP
604 #include C1_LIRGENERATOR_MD_HPP
605 #endif
606 };
607 
608 
609 class LIRItem: public CompilationResourceObj {
610  private:
611   Value         _value;
612   LIRGenerator* _gen;
613   LIR_Opr       _result;
614   bool          _destroys_register;
615   LIR_Opr       _new_result;
616 
617   LIRGenerator* gen() const { return _gen; }
618 
619  public:
620   LIRItem(Value value, LIRGenerator* gen) {
621     _destroys_register = false;
622     _gen = gen;
623     set_instruction(value);
624   }
625 
626   LIRItem(LIRGenerator* gen) {
627     _destroys_register = false;
628     _gen = gen;
629     _result = LIR_OprFact::illegalOpr;
630     set_instruction(NULL);
631   }
632 
633   void set_instruction(Value value) {
634     _value = value;
635     _result = LIR_OprFact::illegalOpr;
636     if (_value != NULL) {
637       _gen->walk(_value);
638       _result = _value->operand();
639     }
640     _new_result = LIR_OprFact::illegalOpr;
641   }
642 
643   Value value() const          { return _value;          }
644   ValueType* type() const      { return value()->type(); }
645   LIR_Opr result()             {
646     assert(!_destroys_register || (!_result->is_register() || _result->is_virtual()),
647            "shouldn't use set_destroys_register with physical regsiters");
648     if (_destroys_register && _result->is_register()) {
649       if (_new_result->is_illegal()) {
650         _new_result = _gen->new_register(type());
651         gen()->lir()->move(_result, _new_result);
652       }
653       return _new_result;
654     } else {
655       return _result;
656     }
657     return _result;
658   }
659 
660   void set_result(LIR_Opr opr);
661 
662   void load_item();
663   void load_byte_item();
664   void load_nonconstant(S390_ONLY(int bits = 20));
665   // load any values which can't be expressed as part of a single store instruction
666   void load_for_store(BasicType store_type);
667   void load_item_force(LIR_Opr reg);
668 
669   void dont_load_item() {
670     // do nothing
671   }
672 
673   void set_destroys_register() {
674     _destroys_register = true;
675   }
676 
677   bool is_constant() const { return value()->as_Constant() != NULL; }
678   bool is_stack()          { return result()->is_stack(); }
679   bool is_register()       { return result()->is_register(); }
680 
681   ciObject* get_jobject_constant() const;
682   jint      get_jint_constant() const;
683   jlong     get_jlong_constant() const;
684   jfloat    get_jfloat_constant() const;
685   jdouble   get_jdouble_constant() const;
686   jint      get_address_constant() const;
687 };
688 
689 #endif // SHARE_C1_C1_LIRGENERATOR_HPP