1 /*
   2  * Copyright (c) 2005, 2016, 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_VM_C1_C1_LIRGENERATOR_HPP
  26 #define SHARE_VM_C1_C1_LIRGENERATOR_HPP
  27 
  28 #include "c1/c1_Instruction.hpp"
  29 #include "c1/c1_LIR.hpp"
  30 #include "ci/ciMethodData.hpp"
  31 #include "utilities/macros.hpp"
  32 #include "utilities/sizes.hpp"
  33 
  34 // The classes responsible for code emission and register allocation
  35 
  36 
  37 class LIRGenerator;
  38 class LIREmitter;
  39 class Invoke;
  40 class SwitchRange;
  41 class LIRItem;
  42 
  43 typedef GrowableArray<LIRItem*> LIRItemList;
  44 
  45 class SwitchRange: public CompilationResourceObj {
  46  private:
  47   int _low_key;
  48   int _high_key;
  49   BlockBegin* _sux;
  50  public:
  51   SwitchRange(int start_key, BlockBegin* sux): _low_key(start_key), _high_key(start_key), _sux(sux) {}
  52   void set_high_key(int key) { _high_key = key; }
  53 
  54   int high_key() const { return _high_key; }
  55   int low_key() const { return _low_key; }
  56   BlockBegin* sux() const { return _sux; }
  57 };
  58 
  59 typedef GrowableArray<SwitchRange*> SwitchRangeArray;
  60 typedef GrowableArray<SwitchRange*> SwitchRangeList;
  61 
  62 class ResolveNode;
  63 
  64 typedef GrowableArray<ResolveNode*> NodeList;
  65 
  66 // Node objects form a directed graph of LIR_Opr
  67 // Edges between Nodes represent moves from one Node to its destinations
  68 class ResolveNode: public CompilationResourceObj {
  69  private:
  70   LIR_Opr    _operand;       // the source or destinaton
  71   NodeList   _destinations;  // for the operand
  72   bool       _assigned;      // Value assigned to this Node?
  73   bool       _visited;       // Node already visited?
  74   bool       _start_node;    // Start node already visited?
  75 
  76  public:
  77   ResolveNode(LIR_Opr operand)
  78     : _operand(operand)
  79     , _assigned(false)
  80     , _visited(false)
  81     , _start_node(false) {};
  82 
  83   // accessors
  84   LIR_Opr operand() const           { return _operand; }
  85   int no_of_destinations() const    { return _destinations.length(); }
  86   ResolveNode* destination_at(int i)     { return _destinations.at(i); }
  87   bool assigned() const             { return _assigned; }
  88   bool visited() const              { return _visited; }
  89   bool start_node() const           { return _start_node; }
  90 
  91   // modifiers
  92   void append(ResolveNode* dest)         { _destinations.append(dest); }
  93   void set_assigned()               { _assigned = true; }
  94   void set_visited()                { _visited = true; }
  95   void set_start_node()             { _start_node = true; }
  96 };
  97 
  98 
  99 // This is shared state to be used by the PhiResolver so the operand
 100 // arrays don't have to be reallocated for reach resolution.
 101 class PhiResolverState: public CompilationResourceObj {
 102   friend class PhiResolver;
 103 
 104  private:
 105   NodeList _virtual_operands; // Nodes where the operand is a virtual register
 106   NodeList _other_operands;   // Nodes where the operand is not a virtual register
 107   NodeList _vreg_table;       // Mapping from virtual register to Node
 108 
 109  public:
 110   PhiResolverState() {}
 111 
 112   void reset(int max_vregs);
 113 };
 114 
 115 
 116 // class used to move value of phi operand to phi function
 117 class PhiResolver: public CompilationResourceObj {
 118  private:
 119   LIRGenerator*     _gen;
 120   PhiResolverState& _state; // temporary state cached by LIRGenerator
 121 
 122   ResolveNode*   _loop;
 123   LIR_Opr _temp;
 124 
 125   // access to shared state arrays
 126   NodeList& virtual_operands() { return _state._virtual_operands; }
 127   NodeList& other_operands()   { return _state._other_operands;   }
 128   NodeList& vreg_table()       { return _state._vreg_table;       }
 129 
 130   ResolveNode* create_node(LIR_Opr opr, bool source);
 131   ResolveNode* source_node(LIR_Opr opr)      { return create_node(opr, true); }
 132   ResolveNode* destination_node(LIR_Opr opr) { return create_node(opr, false); }
 133 
 134   void emit_move(LIR_Opr src, LIR_Opr dest);
 135   void move_to_temp(LIR_Opr src);
 136   void move_temp_to(LIR_Opr dest);
 137   void move(ResolveNode* src, ResolveNode* dest);
 138 
 139   LIRGenerator* gen() {
 140     return _gen;
 141   }
 142 
 143  public:
 144   PhiResolver(LIRGenerator* _lir_gen, int max_vregs);
 145   ~PhiResolver();
 146 
 147   void move(LIR_Opr src, LIR_Opr dest);
 148 };
 149 
 150 
 151 // only the classes below belong in the same file
 152 class LIRGenerator: public InstructionVisitor, public BlockClosure {
 153  // LIRGenerator should never get instatiated on the heap.
 154  private:
 155   void* operator new(size_t size) throw();
 156   void* operator new[](size_t size) throw();
 157   void operator delete(void* p) { ShouldNotReachHere(); }
 158   void operator delete[](void* p) { ShouldNotReachHere(); }
 159 
 160   Compilation*  _compilation;
 161   ciMethod*     _method;    // method that we are compiling
 162   PhiResolverState  _resolver_state;
 163   BlockBegin*   _block;
 164   int           _virtual_register_number;
 165   Values        _instruction_for_operand;
 166   BitMap2D      _vreg_flags; // flags which can be set on a per-vreg basis
 167   LIR_List*     _lir;
 168   BarrierSet*   _bs;
 169 
 170   LIRGenerator* gen() {
 171     return this;
 172   }
 173 
 174   void print_if_not_loaded(const NewInstance* new_instance) PRODUCT_RETURN;
 175 
 176 #ifdef ASSERT
 177   LIR_List* lir(const char * file, int line) const {
 178     _lir->set_file_and_line(file, line);
 179     return _lir;
 180   }
 181 #endif
 182   LIR_List* lir() const {
 183     return _lir;
 184   }
 185 
 186   // a simple cache of constants used within a block
 187   GrowableArray<LIR_Const*>       _constants;
 188   LIR_OprList                     _reg_for_constants;
 189   Values                          _unpinned_constants;
 190 
 191   friend class PhiResolver;
 192 
 193   // unified bailout support
 194   void bailout(const char* msg) const            { compilation()->bailout(msg); }
 195   bool bailed_out() const                        { return compilation()->bailed_out(); }
 196 
 197   void block_do_prolog(BlockBegin* block);
 198   void block_do_epilog(BlockBegin* block);
 199 
 200   // register allocation
 201   LIR_Opr rlock(Value instr);                      // lock a free register
 202   LIR_Opr rlock_result(Value instr);
 203   LIR_Opr rlock_result(Value instr, BasicType type);
 204   LIR_Opr rlock_byte(BasicType type);
 205   LIR_Opr rlock_callee_saved(BasicType type);
 206 
 207   // get a constant into a register and get track of what register was used
 208   LIR_Opr load_constant(Constant* x);
 209   LIR_Opr load_constant(LIR_Const* constant);
 210 
 211   // Given an immediate value, return an operand usable in logical ops.
 212   LIR_Opr load_immediate(int x, BasicType type);
 213 
 214   void  set_result(Value x, LIR_Opr opr)           {
 215     assert(opr->is_valid(), "must set to valid value");
 216     assert(x->operand()->is_illegal(), "operand should never change");
 217     assert(!opr->is_register() || opr->is_virtual(), "should never set result to a physical register");
 218     x->set_operand(opr);
 219     assert(opr == x->operand(), "must be");
 220     if (opr->is_virtual()) {
 221       _instruction_for_operand.at_put_grow(opr->vreg_number(), x, NULL);
 222     }
 223   }
 224   void  set_no_result(Value x)                     { assert(!x->has_uses(), "can't have use"); x->clear_operand(); }
 225 
 226   friend class LIRItem;
 227 
 228   LIR_Opr round_item(LIR_Opr opr);
 229   LIR_Opr force_to_spill(LIR_Opr value, BasicType t);
 230 
 231   PhiResolverState& resolver_state() { return _resolver_state; }
 232 
 233   void  move_to_phi(PhiResolver* resolver, Value cur_val, Value sux_val);
 234   void  move_to_phi(ValueStack* cur_state);
 235 
 236   // code emission
 237   void do_ArithmeticOp_Long   (ArithmeticOp*    x);
 238   void do_ArithmeticOp_Int    (ArithmeticOp*    x);
 239   void do_ArithmeticOp_FPU    (ArithmeticOp*    x);
 240 
 241   // platform dependent
 242   LIR_Opr getThreadPointer();
 243 
 244   void do_RegisterFinalizer(Intrinsic* x);
 245   void do_isInstance(Intrinsic* x);
 246   void do_isPrimitive(Intrinsic* x);
 247   void do_getClass(Intrinsic* x);
 248   void do_currentThread(Intrinsic* x);
 249   void do_FmaIntrinsic(Intrinsic* x);
 250   void do_MathIntrinsic(Intrinsic* x);
 251   void do_LibmIntrinsic(Intrinsic* x);
 252   void do_ArrayCopy(Intrinsic* x);
 253   void do_CompareAndSwap(Intrinsic* x, ValueType* type);
 254   void do_NIOCheckIndex(Intrinsic* x);
 255   void do_FPIntrinsics(Intrinsic* x);
 256   void do_Reference_get(Intrinsic* x);
 257   void do_update_CRC32(Intrinsic* x);
 258   void do_update_CRC32C(Intrinsic* x);
 259   void do_vectorizedMismatch(Intrinsic* x);
 260 
 261   LIR_Opr call_runtime(BasicTypeArray* signature, LIRItemList* args, address entry, ValueType* result_type, CodeEmitInfo* info);
 262   LIR_Opr call_runtime(BasicTypeArray* signature, LIR_OprList* args, address entry, ValueType* result_type, CodeEmitInfo* info);
 263 
 264   // convenience functions
 265   LIR_Opr call_runtime(Value arg1, address entry, ValueType* result_type, CodeEmitInfo* info);
 266   LIR_Opr call_runtime(Value arg1, Value arg2, address entry, ValueType* result_type, CodeEmitInfo* info);
 267 
 268   // GC Barriers
 269 
 270   // generic interface
 271 
 272   void pre_barrier(LIR_Opr addr_opr, LIR_Opr pre_val, bool do_load, bool patch, CodeEmitInfo* info);
 273   void post_barrier(LIR_OprDesc* addr, LIR_OprDesc* new_val);
 274 
 275   // specific implementations
 276   // pre barriers
 277 
 278   void G1SATBCardTableModRef_pre_barrier(LIR_Opr addr_opr, LIR_Opr pre_val,
 279                                          bool do_load, bool patch, CodeEmitInfo* info);
 280 
 281   // post barriers
 282 
 283   void G1SATBCardTableModRef_post_barrier(LIR_OprDesc* addr, LIR_OprDesc* new_val);
 284   void CardTableModRef_post_barrier(LIR_OprDesc* addr, LIR_OprDesc* new_val);
 285 #ifdef CARDTABLEMODREF_POST_BARRIER_HELPER
 286   void CardTableModRef_post_barrier_helper(LIR_OprDesc* addr, LIR_Const* card_table_base);
 287 #endif
 288 
 289 
 290   static LIR_Opr result_register_for(ValueType* type, bool callee = false);
 291 
 292   ciObject* get_jobject_constant(Value value);
 293 
 294   LIRItemList* invoke_visit_arguments(Invoke* x);
 295   void invoke_load_arguments(Invoke* x, LIRItemList* args, const LIR_OprList* arg_list);
 296 
 297   void trace_block_entry(BlockBegin* block);
 298 
 299   // volatile field operations are never patchable because a klass
 300   // must be loaded to know it's volatile which means that the offset
 301   // it always known as well.
 302   void volatile_field_store(LIR_Opr value, LIR_Address* address, CodeEmitInfo* info);
 303   void volatile_field_load(LIR_Address* address, LIR_Opr result, CodeEmitInfo* info);
 304 
 305   void put_Object_unsafe(LIR_Opr src, LIR_Opr offset, LIR_Opr data, BasicType type, bool is_volatile);
 306   void get_Object_unsafe(LIR_Opr dest, LIR_Opr src, LIR_Opr offset, BasicType type, bool is_volatile);
 307 
 308   void arithmetic_call_op (Bytecodes::Code code, LIR_Opr result, LIR_OprList* args);
 309 
 310   void increment_counter(address counter, BasicType type, int step = 1);
 311   void increment_counter(LIR_Address* addr, int step = 1);
 312 
 313   // is_strictfp is only needed for mul and div (and only generates different code on i486)
 314   void arithmetic_op(Bytecodes::Code code, LIR_Opr result, LIR_Opr left, LIR_Opr right, bool is_strictfp, LIR_Opr tmp, CodeEmitInfo* info = NULL);
 315   // machine dependent.  returns true if it emitted code for the multiply
 316   bool strength_reduce_multiply(LIR_Opr left, jint constant, LIR_Opr result, LIR_Opr tmp);
 317 
 318   void store_stack_parameter (LIR_Opr opr, ByteSize offset_from_sp_in_bytes);
 319 
 320   void klass2reg_with_patching(LIR_Opr r, ciMetadata* obj, CodeEmitInfo* info, bool need_resolve = false);
 321 
 322   // this loads the length and compares against the index
 323   void array_range_check          (LIR_Opr array, LIR_Opr index, CodeEmitInfo* null_check_info, CodeEmitInfo* range_check_info);
 324   // For java.nio.Buffer.checkIndex
 325   void nio_range_check            (LIR_Opr buffer, LIR_Opr index, LIR_Opr result, CodeEmitInfo* info);
 326 
 327   void arithmetic_op_int  (Bytecodes::Code code, LIR_Opr result, LIR_Opr left, LIR_Opr right, LIR_Opr tmp);
 328   void arithmetic_op_long (Bytecodes::Code code, LIR_Opr result, LIR_Opr left, LIR_Opr right, CodeEmitInfo* info = NULL);
 329   void arithmetic_op_fpu  (Bytecodes::Code code, LIR_Opr result, LIR_Opr left, LIR_Opr right, bool is_strictfp, LIR_Opr tmp = LIR_OprFact::illegalOpr);
 330 
 331   void shift_op   (Bytecodes::Code code, LIR_Opr dst_reg, LIR_Opr value, LIR_Opr count, LIR_Opr tmp);
 332 
 333   void logic_op   (Bytecodes::Code code, LIR_Opr dst_reg, LIR_Opr left, LIR_Opr right);
 334 
 335   void monitor_enter (LIR_Opr object, LIR_Opr lock, LIR_Opr hdr, LIR_Opr scratch, int monitor_no, CodeEmitInfo* info_for_exception, CodeEmitInfo* info);
 336   void monitor_exit  (LIR_Opr object, LIR_Opr lock, LIR_Opr hdr, LIR_Opr scratch, int monitor_no);
 337 
 338   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);
 339 
 340   // machine dependent
 341   void cmp_mem_int(LIR_Condition condition, LIR_Opr base, int disp, int c, CodeEmitInfo* info);
 342   void cmp_reg_mem(LIR_Condition condition, LIR_Opr reg, LIR_Opr base, int disp, BasicType type, CodeEmitInfo* info);
 343 
 344   void arraycopy_helper(Intrinsic* x, int* flags, ciArrayKlass** expected_type);
 345 
 346   // returns a LIR_Address to address an array location.  May also
 347   // emit some code as part of address calculation.  If
 348   // needs_card_mark is true then compute the full address for use by
 349   // both the store and the card mark.
 350   LIR_Address* generate_address(LIR_Opr base,
 351                                 LIR_Opr index, int shift,
 352                                 int disp,
 353                                 BasicType type);
 354   LIR_Address* generate_address(LIR_Opr base, int disp, BasicType type) {
 355     return generate_address(base, LIR_OprFact::illegalOpr, 0, disp, type);
 356   }
 357   LIR_Address* emit_array_address(LIR_Opr array_opr, LIR_Opr index_opr, BasicType type, bool needs_card_mark);
 358 
 359   // the helper for generate_address
 360   void add_large_constant(LIR_Opr src, int c, LIR_Opr dest);
 361 
 362   // machine preferences and characteristics
 363   bool can_inline_as_constant(Value i S390_ONLY(COMMA int bits = 20)) const;
 364   bool can_inline_as_constant(LIR_Const* c) const;
 365   bool can_store_as_constant(Value i, BasicType type) const;
 366 
 367   LIR_Opr safepoint_poll_register();
 368 
 369   void profile_branch(If* if_instr, If::Condition cond);
 370   void increment_event_counter_impl(CodeEmitInfo* info,
 371                                     ciMethod *method, int frequency,
 372                                     int bci, bool backedge, bool notify);
 373   void increment_event_counter(CodeEmitInfo* info, int bci, bool backedge);
 374   void increment_invocation_counter(CodeEmitInfo *info) {
 375     if (compilation()->count_invocations()) {
 376       increment_event_counter(info, InvocationEntryBci, false);
 377     }
 378   }
 379   void increment_backedge_counter(CodeEmitInfo* info, int bci) {
 380     if (compilation()->count_backedges()) {
 381       increment_event_counter(info, bci, true);
 382     }
 383   }
 384   void decrement_age(CodeEmitInfo* info);
 385   CodeEmitInfo* state_for(Instruction* x, ValueStack* state, bool ignore_xhandler = false);
 386   CodeEmitInfo* state_for(Instruction* x);
 387 
 388   // allocates a virtual register for this instruction if
 389   // one isn't already allocated.  Only for Phi and Local.
 390   LIR_Opr operand_for_instruction(Instruction *x);
 391 
 392   void set_block(BlockBegin* block)              { _block = block; }
 393 
 394   void block_prolog(BlockBegin* block);
 395   void block_epilog(BlockBegin* block);
 396 
 397   void do_root (Instruction* instr);
 398   void walk    (Instruction* instr);
 399 
 400   void bind_block_entry(BlockBegin* block);
 401   void start_block(BlockBegin* block);
 402 
 403   LIR_Opr new_register(BasicType type);
 404   LIR_Opr new_register(Value value)              { return new_register(as_BasicType(value->type())); }
 405   LIR_Opr new_register(ValueType* type)          { return new_register(as_BasicType(type)); }
 406 
 407   // returns a register suitable for doing pointer math
 408   LIR_Opr new_pointer_register() {
 409 #ifdef _LP64
 410     return new_register(T_LONG);
 411 #else
 412     return new_register(T_INT);
 413 #endif
 414   }
 415 
 416   static LIR_Condition lir_cond(If::Condition cond) {
 417     LIR_Condition l = lir_cond_unknown;
 418     switch (cond) {
 419     case If::eql: l = lir_cond_equal;        break;
 420     case If::neq: l = lir_cond_notEqual;     break;
 421     case If::lss: l = lir_cond_less;         break;
 422     case If::leq: l = lir_cond_lessEqual;    break;
 423     case If::geq: l = lir_cond_greaterEqual; break;
 424     case If::gtr: l = lir_cond_greater;      break;
 425     case If::aeq: l = lir_cond_aboveEqual;   break;
 426     case If::beq: l = lir_cond_belowEqual;   break;
 427     default: fatal("You must pass valid If::Condition");
 428     };
 429     return l;
 430   }
 431 
 432 #ifdef __SOFTFP__
 433   void do_soft_float_compare(If *x);
 434 #endif // __SOFTFP__
 435 
 436   void init();
 437 
 438   SwitchRangeArray* create_lookup_ranges(TableSwitch* x);
 439   SwitchRangeArray* create_lookup_ranges(LookupSwitch* x);
 440   void do_SwitchRanges(SwitchRangeArray* x, LIR_Opr value, BlockBegin* default_sux);
 441 
 442 #ifdef TRACE_HAVE_INTRINSICS
 443   void do_ClassIDIntrinsic(Intrinsic* x);
 444   void do_getBufferWriter(Intrinsic* x);
 445 #endif
 446 
 447   void do_RuntimeCall(address routine, Intrinsic* x);
 448 
 449   ciKlass* profile_type(ciMethodData* md, int md_first_offset, int md_offset, intptr_t profiled_k,
 450                         Value arg, LIR_Opr& mdp, bool not_null, ciKlass* signature_at_call_k,
 451                         ciKlass* callee_signature_k);
 452   void profile_arguments(ProfileCall* x);
 453   void profile_parameters(Base* x);
 454   void profile_parameters_at_call(ProfileCall* x);
 455   LIR_Opr maybe_mask_boolean(StoreIndexed* x, LIR_Opr array, LIR_Opr value, CodeEmitInfo*& null_check_info);
 456 
 457  public:
 458   Compilation*  compilation() const              { return _compilation; }
 459   FrameMap*     frame_map() const                { return _compilation->frame_map(); }
 460   ciMethod*     method() const                   { return _method; }
 461   BlockBegin*   block() const                    { return _block; }
 462   IRScope*      scope() const                    { return block()->scope(); }
 463 
 464   int max_virtual_register_number() const        { return _virtual_register_number; }
 465 
 466   void block_do(BlockBegin* block);
 467 
 468   // Flags that can be set on vregs
 469   enum VregFlag {
 470       must_start_in_memory = 0  // needs to be assigned a memory location at beginning, but may then be loaded in a register
 471     , callee_saved     = 1    // must be in a callee saved register
 472     , byte_reg         = 2    // must be in a byte register
 473     , num_vreg_flags
 474 
 475   };
 476 
 477   LIRGenerator(Compilation* compilation, ciMethod* method)
 478     : _compilation(compilation)
 479     , _method(method)
 480     , _virtual_register_number(LIR_OprDesc::vreg_base)
 481     , _vreg_flags(num_vreg_flags) {
 482     init();
 483   }
 484 
 485   // for virtual registers, maps them back to Phi's or Local's
 486   Instruction* instruction_for_opr(LIR_Opr opr);
 487   Instruction* instruction_for_vreg(int reg_num);
 488 
 489   void set_vreg_flag   (int vreg_num, VregFlag f);
 490   bool is_vreg_flag_set(int vreg_num, VregFlag f);
 491   void set_vreg_flag   (LIR_Opr opr,  VregFlag f) { set_vreg_flag(opr->vreg_number(), f); }
 492   bool is_vreg_flag_set(LIR_Opr opr,  VregFlag f) { return is_vreg_flag_set(opr->vreg_number(), f); }
 493 
 494   // statics
 495   static LIR_Opr exceptionOopOpr();
 496   static LIR_Opr exceptionPcOpr();
 497   static LIR_Opr divInOpr();
 498   static LIR_Opr divOutOpr();
 499   static LIR_Opr remOutOpr();
 500 #ifdef S390
 501   // On S390 we can do ldiv, lrem without RT call.
 502   static LIR_Opr ldivInOpr();
 503   static LIR_Opr ldivOutOpr();
 504   static LIR_Opr lremOutOpr();
 505 #endif
 506   static LIR_Opr shiftCountOpr();
 507   LIR_Opr syncLockOpr();
 508   LIR_Opr syncTempOpr();
 509   LIR_Opr atomicLockOpr();
 510 
 511   // returns a register suitable for saving the thread in a
 512   // call_runtime_leaf if one is needed.
 513   LIR_Opr getThreadTemp();
 514 
 515   // visitor functionality
 516   virtual void do_Phi            (Phi*             x);
 517   virtual void do_Local          (Local*           x);
 518   virtual void do_Constant       (Constant*        x);
 519   virtual void do_LoadField      (LoadField*       x);
 520   virtual void do_StoreField     (StoreField*      x);
 521   virtual void do_ArrayLength    (ArrayLength*     x);
 522   virtual void do_LoadIndexed    (LoadIndexed*     x);
 523   virtual void do_StoreIndexed   (StoreIndexed*    x);
 524   virtual void do_NegateOp       (NegateOp*        x);
 525   virtual void do_ArithmeticOp   (ArithmeticOp*    x);
 526   virtual void do_ShiftOp        (ShiftOp*         x);
 527   virtual void do_LogicOp        (LogicOp*         x);
 528   virtual void do_CompareOp      (CompareOp*       x);
 529   virtual void do_IfOp           (IfOp*            x);
 530   virtual void do_Convert        (Convert*         x);
 531   virtual void do_NullCheck      (NullCheck*       x);
 532   virtual void do_TypeCast       (TypeCast*        x);
 533   virtual void do_Invoke         (Invoke*          x);
 534   virtual void do_NewInstance    (NewInstance*     x);
 535   virtual void do_NewTypeArray   (NewTypeArray*    x);
 536   virtual void do_NewObjectArray (NewObjectArray*  x);
 537   virtual void do_NewMultiArray  (NewMultiArray*   x);
 538   virtual void do_CheckCast      (CheckCast*       x);
 539   virtual void do_InstanceOf     (InstanceOf*      x);
 540   virtual void do_MonitorEnter   (MonitorEnter*    x);
 541   virtual void do_MonitorExit    (MonitorExit*     x);
 542   virtual void do_Intrinsic      (Intrinsic*       x);
 543   virtual void do_BlockBegin     (BlockBegin*      x);
 544   virtual void do_Goto           (Goto*            x);
 545   virtual void do_If             (If*              x);
 546   virtual void do_IfInstanceOf   (IfInstanceOf*    x);
 547   virtual void do_TableSwitch    (TableSwitch*     x);
 548   virtual void do_LookupSwitch   (LookupSwitch*    x);
 549   virtual void do_Return         (Return*          x);
 550   virtual void do_Throw          (Throw*           x);
 551   virtual void do_Base           (Base*            x);
 552   virtual void do_OsrEntry       (OsrEntry*        x);
 553   virtual void do_ExceptionObject(ExceptionObject* x);
 554   virtual void do_RoundFP        (RoundFP*         x);
 555   virtual void do_UnsafeGetRaw   (UnsafeGetRaw*    x);
 556   virtual void do_UnsafePutRaw   (UnsafePutRaw*    x);
 557   virtual void do_UnsafeGetObject(UnsafeGetObject* x);
 558   virtual void do_UnsafePutObject(UnsafePutObject* x);
 559   virtual void do_UnsafeGetAndSetObject(UnsafeGetAndSetObject* x);
 560   virtual void do_ProfileCall    (ProfileCall*     x);
 561   virtual void do_ProfileReturnType (ProfileReturnType* x);
 562   virtual void do_ProfileInvoke  (ProfileInvoke*   x);
 563   virtual void do_RuntimeCall    (RuntimeCall*     x);
 564   virtual void do_MemBar         (MemBar*          x);
 565   virtual void do_RangeCheckPredicate(RangeCheckPredicate* x);
 566 #ifdef ASSERT
 567   virtual void do_Assert         (Assert*          x);
 568 #endif
 569 
 570 #ifdef C1_LIRGENERATOR_MD_HPP
 571 #include C1_LIRGENERATOR_MD_HPP
 572 #endif
 573 };
 574 
 575 
 576 class LIRItem: public CompilationResourceObj {
 577  private:
 578   Value         _value;
 579   LIRGenerator* _gen;
 580   LIR_Opr       _result;
 581   bool          _destroys_register;
 582   LIR_Opr       _new_result;
 583 
 584   LIRGenerator* gen() const { return _gen; }
 585 
 586  public:
 587   LIRItem(Value value, LIRGenerator* gen) {
 588     _destroys_register = false;
 589     _gen = gen;
 590     set_instruction(value);
 591   }
 592 
 593   LIRItem(LIRGenerator* gen) {
 594     _destroys_register = false;
 595     _gen = gen;
 596     _result = LIR_OprFact::illegalOpr;
 597     set_instruction(NULL);
 598   }
 599 
 600   void set_instruction(Value value) {
 601     _value = value;
 602     _result = LIR_OprFact::illegalOpr;
 603     if (_value != NULL) {
 604       _gen->walk(_value);
 605       _result = _value->operand();
 606     }
 607     _new_result = LIR_OprFact::illegalOpr;
 608   }
 609 
 610   Value value() const          { return _value;          }
 611   ValueType* type() const      { return value()->type(); }
 612   LIR_Opr result()             {
 613     assert(!_destroys_register || (!_result->is_register() || _result->is_virtual()),
 614            "shouldn't use set_destroys_register with physical regsiters");
 615     if (_destroys_register && _result->is_register()) {
 616       if (_new_result->is_illegal()) {
 617         _new_result = _gen->new_register(type());
 618         gen()->lir()->move(_result, _new_result);
 619       }
 620       return _new_result;
 621     } else {
 622       return _result;
 623     }
 624     return _result;
 625   }
 626 
 627   void set_result(LIR_Opr opr);
 628 
 629   void load_item();
 630   void load_byte_item();
 631   void load_nonconstant(S390_ONLY(int bits = 20));
 632   // load any values which can't be expressed as part of a single store instruction
 633   void load_for_store(BasicType store_type);
 634   void load_item_force(LIR_Opr reg);
 635 
 636   void dont_load_item() {
 637     // do nothing
 638   }
 639 
 640   void set_destroys_register() {
 641     _destroys_register = true;
 642   }
 643 
 644   bool is_constant() const { return value()->as_Constant() != NULL; }
 645   bool is_stack()          { return result()->is_stack(); }
 646   bool is_register()       { return result()->is_register(); }
 647 
 648   ciObject* get_jobject_constant() const;
 649   jint      get_jint_constant() const;
 650   jlong     get_jlong_constant() const;
 651   jfloat    get_jfloat_constant() const;
 652   jdouble   get_jdouble_constant() const;
 653   jint      get_address_constant() const;
 654 };
 655 
 656 #endif // SHARE_VM_C1_C1_LIRGENERATOR_HPP