1 /*
   2  * Copyright 1998-2009 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 // CodeBlob - superclass for all entries in the CodeCache.
  26 //
  27 // Suptypes are:
  28 //   nmethod            : Compiled Java methods (include method that calls to native code)
  29 //   RuntimeStub        : Call to VM runtime methods
  30 //   DeoptimizationBlob : Used for deoptimizatation
  31 //   ExceptionBlob      : Used for stack unrolling
  32 //   SafepointBlob      : Used to handle illegal instruction exceptions
  33 //
  34 //
  35 // Layout:
  36 //   - header
  37 //   - relocation
  38 //   - instruction space
  39 //   - data space
  40 class DeoptimizationBlob;
  41 
  42 class CodeBlob VALUE_OBJ_CLASS_SPEC {
  43 
  44   friend class VMStructs;
  45 
  46  private:
  47   const char* _name;
  48   int        _size;                              // total size of CodeBlob in bytes
  49   int        _header_size;                       // size of header (depends on subclass)
  50   int        _relocation_size;                   // size of relocation
  51   int        _instructions_offset;               // offset to where instructions region begins
  52   int        _frame_complete_offset;             // instruction offsets in [0.._frame_complete_offset) have
  53                                                  // not finished setting up their frame. Beware of pc's in
  54                                                  // that range. There is a similar range(s) on returns
  55                                                  // which we don't detect.
  56   int        _data_offset;                       // offset to where data region begins
  57   int        _oops_offset;                       // offset to where embedded oop table begins (inside data)
  58   int        _oops_length;                       // number of embedded oops
  59   int        _frame_size;                        // size of stack frame
  60   OopMapSet* _oop_maps;                          // OopMap for this CodeBlob
  61   CodeComments _comments;
  62 
  63   friend class OopRecorder;
  64 
  65   void fix_oop_relocations(address begin, address end, bool initialize_immediates);
  66   inline void initialize_immediate_oop(oop* dest, jobject handle);
  67 
  68  public:
  69   // Returns the space needed for CodeBlob
  70   static unsigned int allocation_size(CodeBuffer* cb, int header_size);
  71 
  72   // Creation
  73   // a) simple CodeBlob
  74   // frame_complete is the offset from the beginning of the instructions
  75   // to where the frame setup (from stackwalk viewpoint) is complete.
  76   CodeBlob(const char* name, int header_size, int size, int frame_complete, int locs_size);
  77 
  78   // b) full CodeBlob
  79   CodeBlob(
  80     const char* name,
  81     CodeBuffer* cb,
  82     int         header_size,
  83     int         size,
  84     int         frame_complete,
  85     int         frame_size,
  86     OopMapSet*  oop_maps
  87   );
  88 
  89   // Deletion
  90   void flush();
  91 
  92   // Typing
  93   virtual bool is_buffer_blob() const            { return false; }
  94   virtual bool is_nmethod() const                { return false; }
  95   virtual bool is_runtime_stub() const           { return false; }
  96   virtual bool is_deoptimization_stub() const    { return false; }
  97   virtual bool is_uncommon_trap_stub() const     { return false; }
  98   virtual bool is_exception_stub() const         { return false; }
  99   virtual bool is_safepoint_stub() const         { return false; }
 100   virtual bool is_adapter_blob() const           { return false; }
 101 
 102   virtual bool is_compiled_by_c2() const         { return false; }
 103   virtual bool is_compiled_by_c1() const         { return false; }
 104 
 105   // Casting
 106   nmethod* as_nmethod_or_null()                  { return is_nmethod() ? (nmethod*) this : NULL; }
 107 
 108   // Boundaries
 109   address    header_begin() const                { return (address)    this; }
 110   address    header_end() const                  { return ((address)   this) + _header_size; };
 111   relocInfo* relocation_begin() const            { return (relocInfo*) header_end(); };
 112   relocInfo* relocation_end() const              { return (relocInfo*)(header_end()   + _relocation_size); }
 113   address    instructions_begin() const          { return (address)    header_begin() + _instructions_offset;  }
 114   address    instructions_end() const            { return (address)    header_begin() + _data_offset; }
 115   address    data_begin() const                  { return (address)    header_begin() + _data_offset; }
 116   address    data_end() const                    { return (address)    header_begin() + _size; }
 117   oop*       oops_begin() const                  { return (oop*)      (header_begin() + _oops_offset); }
 118   oop*       oops_end() const                    { return                oops_begin() + _oops_length; }
 119 
 120   // Offsets
 121   int relocation_offset() const                  { return _header_size; }
 122   int instructions_offset() const                { return _instructions_offset; }
 123   int data_offset() const                        { return _data_offset; }
 124   int oops_offset() const                        { return _oops_offset; }
 125 
 126   // Sizes
 127   int size() const                               { return _size; }
 128   int header_size() const                        { return _header_size; }
 129   int relocation_size() const                    { return (address) relocation_end() - (address) relocation_begin(); }
 130   int instructions_size() const                  { return instructions_end() - instructions_begin();  }
 131   int data_size() const                          { return data_end() - data_begin(); }
 132   int oops_size() const                          { return (address) oops_end() - (address) oops_begin(); }
 133 
 134   // Containment
 135   bool blob_contains(address addr) const         { return header_begin()       <= addr && addr < data_end(); }
 136   bool relocation_contains(relocInfo* addr) const{ return relocation_begin()   <= addr && addr < relocation_end(); }
 137   bool instructions_contains(address addr) const { return instructions_begin() <= addr && addr < instructions_end(); }
 138   bool data_contains(address addr) const         { return data_begin()         <= addr && addr < data_end(); }
 139   bool oops_contains(oop* addr) const            { return oops_begin()         <= addr && addr < oops_end(); }
 140   bool contains(address addr) const              { return instructions_contains(addr); }
 141   bool is_frame_complete_at(address addr) const  { return instructions_contains(addr) &&
 142                                                           addr >= instructions_begin() + _frame_complete_offset; }
 143 
 144   // Relocation support
 145   void fix_oop_relocations(address begin, address end) {
 146     fix_oop_relocations(begin, end, false);
 147   }
 148   void fix_oop_relocations() {
 149     fix_oop_relocations(NULL, NULL, false);
 150   }
 151   relocInfo::relocType reloc_type_for_address(address pc);
 152   bool is_at_poll_return(address pc);
 153   bool is_at_poll_or_poll_return(address pc);
 154 
 155   // Support for oops in scopes and relocs:
 156   // Note: index 0 is reserved for null.
 157   oop  oop_at(int index) const                   { return index == 0? (oop)NULL: *oop_addr_at(index); }
 158   oop* oop_addr_at(int index) const{             // for GC
 159     // relocation indexes are biased by 1 (because 0 is reserved)
 160     assert(index > 0 && index <= _oops_length, "must be a valid non-zero index");
 161     return &oops_begin()[index-1];
 162   }
 163 
 164   void copy_oops(GrowableArray<jobject>* oops);
 165 
 166   // CodeCache support: really only used by the nmethods, but in order to get
 167   // asserts and certain bookkeeping to work in the CodeCache they are defined
 168   // virtual here.
 169   virtual bool is_zombie() const                 { return false; }
 170   virtual bool is_locked_by_vm() const           { return false; }
 171 
 172   virtual bool is_unloaded() const               { return false; }
 173   virtual bool is_not_entrant() const            { return false; }
 174 
 175   // GC support
 176   virtual bool is_alive() const                  = 0;
 177   virtual void do_unloading(BoolObjectClosure* is_alive,
 178                             OopClosure* keep_alive,
 179                             bool unloading_occurred);
 180   virtual void oops_do(OopClosure* f) = 0;
 181   // (All CodeBlob subtypes other than NMethod currently have
 182   // an empty oops_do() method.
 183 
 184   // OopMap for frame
 185   OopMapSet* oop_maps() const                    { return _oop_maps; }
 186   void set_oop_maps(OopMapSet* p);
 187   OopMap* oop_map_for_return_address(address return_address);
 188   virtual void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f)  { ShouldNotReachHere(); }
 189 
 190   // Frame support
 191   int  frame_size() const                        { return _frame_size; }
 192   void set_frame_size(int size)                  { _frame_size = size; }
 193 
 194   // Returns true, if the next frame is responsible for GC'ing oops passed as arguments
 195   virtual bool caller_must_gc_arguments(JavaThread* thread) const { return false; }
 196 
 197   // Naming
 198   const char* name() const                       { return _name; }
 199   void set_name(const char* name)                { _name = name; }
 200 
 201   // Debugging
 202   virtual void verify();
 203   virtual void print() const                     PRODUCT_RETURN;
 204   virtual void print_value_on(outputStream* st) const PRODUCT_RETURN;
 205 
 206   // Print the comment associated with offset on stream, if there is one
 207   void print_block_comment(outputStream* stream, intptr_t offset) {
 208     _comments.print_block_comment(stream, offset);
 209   }
 210 
 211   // Transfer ownership of comments to this CodeBlob
 212   void set_comments(CodeComments& comments) {
 213     _comments.assign(comments);
 214   }
 215 };
 216 
 217 
 218 //----------------------------------------------------------------------------------------------------
 219 // BufferBlob: used to hold non-relocatable machine code such as the interpreter, stubroutines, etc.
 220 
 221 class BufferBlob: public CodeBlob {
 222   friend class VMStructs;
 223  private:
 224   // Creation support
 225   BufferBlob(const char* name, int size);
 226   BufferBlob(const char* name, int size, CodeBuffer* cb);
 227 
 228   void* operator new(size_t s, unsigned size);
 229 
 230  public:
 231   // Creation
 232   static BufferBlob* create(const char* name, int buffer_size);
 233   static BufferBlob* create(const char* name, CodeBuffer* cb);
 234 
 235   static void free(BufferBlob* buf);
 236 
 237   // Typing
 238   bool is_buffer_blob() const                    { return true; }
 239   bool is_adapter_blob() const;
 240 
 241   // GC/Verification support
 242   void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f)  { /* nothing to do */ }
 243   bool is_alive() const                          { return true; }
 244   void do_unloading(BoolObjectClosure* is_alive,
 245                     OopClosure* keep_alive,
 246                     bool unloading_occurred)     { /* do nothing */ }
 247 
 248   void oops_do(OopClosure* f)                    { /* do nothing*/ }
 249 
 250   void verify();
 251   void print() const                             PRODUCT_RETURN;
 252   void print_value_on(outputStream* st) const    PRODUCT_RETURN;
 253 };
 254 
 255 
 256 //----------------------------------------------------------------------------------------------------
 257 // RuntimeStub: describes stubs used by compiled code to call a (static) C++ runtime routine
 258 
 259 class RuntimeStub: public CodeBlob {
 260   friend class VMStructs;
 261  private:
 262   bool        _caller_must_gc_arguments;
 263 
 264   // Creation support
 265   RuntimeStub(
 266     const char* name,
 267     CodeBuffer* cb,
 268     int         size,
 269     int         frame_complete,
 270     int         frame_size,
 271     OopMapSet*  oop_maps,
 272     bool        caller_must_gc_arguments
 273   );
 274 
 275   void* operator new(size_t s, unsigned size);
 276 
 277  public:
 278   // Creation
 279   static RuntimeStub* new_runtime_stub(
 280     const char* stub_name,
 281     CodeBuffer* cb,
 282     int         frame_complete,
 283     int         frame_size,
 284     OopMapSet*  oop_maps,
 285     bool        caller_must_gc_arguments
 286   );
 287 
 288   // Typing
 289   bool is_runtime_stub() const                   { return true; }
 290 
 291   // GC support
 292   bool caller_must_gc_arguments(JavaThread* thread) const { return _caller_must_gc_arguments; }
 293 
 294   address entry_point()                          { return instructions_begin(); }
 295 
 296   // GC/Verification support
 297   void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f)  { /* nothing to do */ }
 298   bool is_alive() const                          { return true; }
 299   void do_unloading(BoolObjectClosure* is_alive,
 300                     OopClosure* keep_alive,
 301                     bool unloading_occurred)     { /* do nothing */ }
 302   void oops_do(OopClosure* f) { /* do-nothing*/ }
 303 
 304   void verify();
 305   void print() const                             PRODUCT_RETURN;
 306   void print_value_on(outputStream* st) const    PRODUCT_RETURN;
 307 };
 308 
 309 
 310 //----------------------------------------------------------------------------------------------------
 311 // Super-class for all blobs that exist in only one instance. Implements default behaviour.
 312 
 313 class SingletonBlob: public CodeBlob {
 314   friend class VMStructs;
 315   public:
 316    SingletonBlob(
 317      const char* name,
 318      CodeBuffer* cb,
 319      int         header_size,
 320      int         size,
 321      int         frame_size,
 322      OopMapSet*  oop_maps
 323    )
 324    : CodeBlob(name, cb, header_size, size, CodeOffsets::frame_never_safe, frame_size, oop_maps)
 325    {};
 326 
 327    bool is_alive() const                         { return true; }
 328    void do_unloading(BoolObjectClosure* is_alive,
 329                      OopClosure* keep_alive,
 330                      bool unloading_occurred)    { /* do-nothing*/ }
 331 
 332    void verify(); // does nothing
 333    void print() const                            PRODUCT_RETURN;
 334    void print_value_on(outputStream* st) const   PRODUCT_RETURN;
 335 };
 336 
 337 
 338 //----------------------------------------------------------------------------------------------------
 339 // DeoptimizationBlob
 340 
 341 class DeoptimizationBlob: public SingletonBlob {
 342   friend class VMStructs;
 343  private:
 344   int _unpack_offset;
 345   int _unpack_with_exception;
 346   int _unpack_with_reexecution;
 347 
 348   int _unpack_with_exception_in_tls;
 349 
 350   // Creation support
 351   DeoptimizationBlob(
 352     CodeBuffer* cb,
 353     int         size,
 354     OopMapSet*  oop_maps,
 355     int         unpack_offset,
 356     int         unpack_with_exception_offset,
 357     int         unpack_with_reexecution_offset,
 358     int         frame_size
 359   );
 360 
 361   void* operator new(size_t s, unsigned size);
 362 
 363  public:
 364   // Creation
 365   static DeoptimizationBlob* create(
 366     CodeBuffer* cb,
 367     OopMapSet*  oop_maps,
 368     int         unpack_offset,
 369     int         unpack_with_exception_offset,
 370     int         unpack_with_reexecution_offset,
 371     int         frame_size
 372   );
 373 
 374   // Typing
 375   bool is_deoptimization_stub() const { return true; }
 376   const DeoptimizationBlob *as_deoptimization_stub() const { return this; }
 377   bool exception_address_is_unpack_entry(address pc) const {
 378     address unpack_pc = unpack();
 379     return (pc == unpack_pc || (pc + frame::pc_return_offset) == unpack_pc);
 380   }
 381 
 382 
 383 
 384 
 385   // GC for args
 386   void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f) { /* Nothing to do */ }
 387 
 388   // Iteration
 389   void oops_do(OopClosure* f) {}
 390 
 391   // Printing
 392   void print_value_on(outputStream* st) const PRODUCT_RETURN;
 393 
 394   address unpack() const                         { return instructions_begin() + _unpack_offset;           }
 395   address unpack_with_exception() const          { return instructions_begin() + _unpack_with_exception;   }
 396   address unpack_with_reexecution() const        { return instructions_begin() + _unpack_with_reexecution; }
 397 
 398   // Alternate entry point for C1 where the exception and issuing pc
 399   // are in JavaThread::_exception_oop and JavaThread::_exception_pc
 400   // instead of being in registers.  This is needed because C1 doesn't
 401   // model exception paths in a way that keeps these registers free so
 402   // there may be live values in those registers during deopt.
 403   void set_unpack_with_exception_in_tls_offset(int offset) {
 404     _unpack_with_exception_in_tls = offset;
 405     assert(contains(instructions_begin() + _unpack_with_exception_in_tls), "must be PC inside codeblob");
 406   }
 407   address unpack_with_exception_in_tls() const   { return instructions_begin() + _unpack_with_exception_in_tls;   }
 408 };
 409 
 410 
 411 //----------------------------------------------------------------------------------------------------
 412 // UncommonTrapBlob (currently only used by Compiler 2)
 413 
 414 #ifdef COMPILER2
 415 
 416 class UncommonTrapBlob: public SingletonBlob {
 417   friend class VMStructs;
 418  private:
 419   // Creation support
 420   UncommonTrapBlob(
 421     CodeBuffer* cb,
 422     int         size,
 423     OopMapSet*  oop_maps,
 424     int         frame_size
 425   );
 426 
 427   void* operator new(size_t s, unsigned size);
 428 
 429  public:
 430   // Creation
 431   static UncommonTrapBlob* create(
 432     CodeBuffer* cb,
 433     OopMapSet*  oop_maps,
 434     int         frame_size
 435   );
 436 
 437   // GC for args
 438   void preserve_callee_argument_oops(frame fr, const RegisterMap *reg_map, OopClosure* f)  { /* nothing to do */ }
 439 
 440   // Typing
 441   bool is_uncommon_trap_stub() const             { return true; }
 442 
 443   // Iteration
 444   void oops_do(OopClosure* f) {}
 445 };
 446 
 447 
 448 //----------------------------------------------------------------------------------------------------
 449 // ExceptionBlob: used for exception unwinding in compiled code (currently only used by Compiler 2)
 450 
 451 class ExceptionBlob: public SingletonBlob {
 452   friend class VMStructs;
 453  private:
 454   // Creation support
 455   ExceptionBlob(
 456     CodeBuffer* cb,
 457     int         size,
 458     OopMapSet*  oop_maps,
 459     int         frame_size
 460   );
 461 
 462   void* operator new(size_t s, unsigned size);
 463 
 464  public:
 465   // Creation
 466   static ExceptionBlob* create(
 467     CodeBuffer* cb,
 468     OopMapSet*  oop_maps,
 469     int         frame_size
 470   );
 471 
 472   // GC for args
 473   void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f)  { /* nothing to do */ }
 474 
 475   // Typing
 476   bool is_exception_stub() const                 { return true; }
 477 
 478   // Iteration
 479   void oops_do(OopClosure* f) {}
 480 };
 481 #endif // COMPILER2
 482 
 483 
 484 //----------------------------------------------------------------------------------------------------
 485 // SafepointBlob: handles illegal_instruction exceptions during a safepoint
 486 
 487 class SafepointBlob: public SingletonBlob {
 488   friend class VMStructs;
 489  private:
 490   // Creation support
 491   SafepointBlob(
 492     CodeBuffer* cb,
 493     int         size,
 494     OopMapSet*  oop_maps,
 495     int         frame_size
 496   );
 497 
 498   void* operator new(size_t s, unsigned size);
 499 
 500  public:
 501   // Creation
 502   static SafepointBlob* create(
 503     CodeBuffer* cb,
 504     OopMapSet*  oop_maps,
 505     int         frame_size
 506   );
 507 
 508   // GC for args
 509   void preserve_callee_argument_oops(frame fr, const RegisterMap* reg_map, OopClosure* f)  { /* nothing to do */ }
 510 
 511   // Typing
 512   bool is_safepoint_stub() const                 { return true; }
 513 
 514   // Iteration
 515   void oops_do(OopClosure* f) {}
 516 };