src/share/vm/asm/codeBuffer.hpp

Wed, 02 Jul 2008 12:55:16 -0700

author
xdono
date
Wed, 02 Jul 2008 12:55:16 -0700
changeset 631
d1605aabd0a1
parent 551
018d5b58dd4f
child 1635
ba263cfb7611
permissions
-rw-r--r--

6719955: Update copyright year
Summary: Update copyright year for files that have been modified in 2008
Reviewed-by: ohair, tbell

     1 /*
     2  * Copyright 1997-2008 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  */
    25 class  CodeComments;
    26 class  AbstractAssembler;
    27 class  MacroAssembler;
    28 class  PhaseCFG;
    29 class  Compile;
    30 class  BufferBlob;
    31 class  CodeBuffer;
    33 class CodeOffsets: public StackObj {
    34 public:
    35   enum Entries { Entry,
    36                  Verified_Entry,
    37                  Frame_Complete, // Offset in the code where the frame setup is (for forte stackwalks) is complete
    38                  OSR_Entry,
    39                  Dtrace_trap = OSR_Entry,  // dtrace probes can never have an OSR entry so reuse it
    40                  Exceptions,     // Offset where exception handler lives
    41                  Deopt,          // Offset where deopt handler lives
    42                  max_Entries };
    44   // special value to note codeBlobs where profile (forte) stack walking is
    45   // always dangerous and suspect.
    47   enum { frame_never_safe = -1 };
    49 private:
    50   int _values[max_Entries];
    52 public:
    53   CodeOffsets() {
    54     _values[Entry] = 0;
    55     _values[Verified_Entry] = 0;
    56     _values[Frame_Complete] = frame_never_safe;
    57     _values[OSR_Entry] = 0;
    58     _values[Exceptions] = -1;
    59     _values[Deopt] = -1;
    60   }
    62   int value(Entries e) { return _values[e]; }
    63   void set_value(Entries e, int val) { _values[e] = val; }
    64 };
    66 // This class represents a stream of code and associated relocations.
    67 // There are a few in each CodeBuffer.
    68 // They are filled concurrently, and concatenated at the end.
    69 class CodeSection VALUE_OBJ_CLASS_SPEC {
    70   friend class CodeBuffer;
    71  public:
    72   typedef int csize_t;  // code size type; would be size_t except for history
    74  private:
    75   address     _start;           // first byte of contents (instructions)
    76   address     _mark;            // user mark, usually an instruction beginning
    77   address     _end;             // current end address
    78   address     _limit;           // last possible (allocated) end address
    79   relocInfo*  _locs_start;      // first byte of relocation information
    80   relocInfo*  _locs_end;        // first byte after relocation information
    81   relocInfo*  _locs_limit;      // first byte after relocation information buf
    82   address     _locs_point;      // last relocated position (grows upward)
    83   bool        _locs_own;        // did I allocate the locs myself?
    84   bool        _frozen;          // no more expansion of this section
    85   char        _index;           // my section number (SECT_INST, etc.)
    86   CodeBuffer* _outer;           // enclosing CodeBuffer
    88   // (Note:  _locs_point used to be called _last_reloc_offset.)
    90   CodeSection() {
    91     _start         = NULL;
    92     _mark          = NULL;
    93     _end           = NULL;
    94     _limit         = NULL;
    95     _locs_start    = NULL;
    96     _locs_end      = NULL;
    97     _locs_limit    = NULL;
    98     _locs_point    = NULL;
    99     _locs_own      = false;
   100     _frozen        = false;
   101     debug_only(_index = -1);
   102     debug_only(_outer = (CodeBuffer*)badAddress);
   103   }
   105   void initialize_outer(CodeBuffer* outer, int index) {
   106     _outer = outer;
   107     _index = index;
   108   }
   110   void initialize(address start, csize_t size = 0) {
   111     assert(_start == NULL, "only one init step, please");
   112     _start         = start;
   113     _mark          = NULL;
   114     _end           = start;
   116     _limit         = start + size;
   117     _locs_point    = start;
   118   }
   120   void initialize_locs(int locs_capacity);
   121   void expand_locs(int new_capacity);
   122   void initialize_locs_from(const CodeSection* source_cs);
   124   // helper for CodeBuffer::expand()
   125   void take_over_code_from(CodeSection* cs) {
   126     _start      = cs->_start;
   127     _mark       = cs->_mark;
   128     _end        = cs->_end;
   129     _limit      = cs->_limit;
   130     _locs_point = cs->_locs_point;
   131   }
   133  public:
   134   address     start() const         { return _start; }
   135   address     mark() const          { return _mark; }
   136   address     end() const           { return _end; }
   137   address     limit() const         { return _limit; }
   138   csize_t     size() const          { return (csize_t)(_end - _start); }
   139   csize_t     mark_off() const      { assert(_mark != NULL, "not an offset");
   140                                       return (csize_t)(_mark - _start); }
   141   csize_t     capacity() const      { return (csize_t)(_limit - _start); }
   142   csize_t     remaining() const     { return (csize_t)(_limit - _end); }
   144   relocInfo*  locs_start() const    { return _locs_start; }
   145   relocInfo*  locs_end() const      { return _locs_end; }
   146   int         locs_count() const    { return (int)(_locs_end - _locs_start); }
   147   relocInfo*  locs_limit() const    { return _locs_limit; }
   148   address     locs_point() const    { return _locs_point; }
   149   csize_t     locs_point_off() const{ return (csize_t)(_locs_point - _start); }
   150   csize_t     locs_capacity() const { return (csize_t)(_locs_limit - _locs_start); }
   151   csize_t     locs_remaining()const { return (csize_t)(_locs_limit - _locs_end); }
   153   int         index() const         { return _index; }
   154   bool        is_allocated() const  { return _start != NULL; }
   155   bool        is_empty() const      { return _start == _end; }
   156   bool        is_frozen() const     { return _frozen; }
   157   bool        has_locs() const      { return _locs_end != NULL; }
   159   CodeBuffer* outer() const         { return _outer; }
   161   // is a given address in this section?  (2nd version is end-inclusive)
   162   bool contains(address pc) const   { return pc >= _start && pc <  _end; }
   163   bool contains2(address pc) const  { return pc >= _start && pc <= _end; }
   164   bool allocates(address pc) const  { return pc >= _start && pc <  _limit; }
   165   bool allocates2(address pc) const { return pc >= _start && pc <= _limit; }
   167   void    set_end(address pc)       { assert(allocates2(pc),""); _end = pc; }
   168   void    set_mark(address pc)      { assert(contains2(pc),"not in codeBuffer");
   169                                       _mark = pc; }
   170   void    set_mark_off(int offset)  { assert(contains2(offset+_start),"not in codeBuffer");
   171                                       _mark = offset + _start; }
   172   void    set_mark()                { _mark = _end; }
   173   void    clear_mark()              { _mark = NULL; }
   175   void    set_locs_end(relocInfo* p) {
   176     assert(p <= locs_limit(), "locs data fits in allocated buffer");
   177     _locs_end = p;
   178   }
   179   void    set_locs_point(address pc) {
   180     assert(pc >= locs_point(), "relocation addr may not decrease");
   181     assert(allocates2(pc),     "relocation addr must be in this section");
   182     _locs_point = pc;
   183   }
   185   // Share a scratch buffer for relocinfo.  (Hacky; saves a resource allocation.)
   186   void initialize_shared_locs(relocInfo* buf, int length);
   188   // Manage labels and their addresses.
   189   address target(Label& L, address branch_pc);
   191   // Emit a relocation.
   192   void relocate(address at, RelocationHolder const& rspec, int format = 0);
   193   void relocate(address at,    relocInfo::relocType rtype, int format = 0) {
   194     if (rtype != relocInfo::none)
   195       relocate(at, Relocation::spec_simple(rtype), format);
   196   }
   198   // alignment requirement for starting offset
   199   // Requirements are that the instruction area and the
   200   // stubs area must start on CodeEntryAlignment, and
   201   // the ctable on sizeof(jdouble)
   202   int alignment() const             { return MAX2((int)sizeof(jdouble), (int)CodeEntryAlignment); }
   204   // Slop between sections, used only when allocating temporary BufferBlob buffers.
   205   static csize_t end_slop()         { return MAX2((int)sizeof(jdouble), (int)CodeEntryAlignment); }
   207   csize_t align_at_start(csize_t off) const { return (csize_t) align_size_up(off, alignment()); }
   209   // Mark a section frozen.  Assign its remaining space to
   210   // the following section.  It will never expand after this point.
   211   inline void freeze();         //  { _outer->freeze_section(this); }
   213   // Ensure there's enough space left in the current section.
   214   // Return true if there was an expansion.
   215   bool maybe_expand_to_ensure_remaining(csize_t amount);
   217 #ifndef PRODUCT
   218   void decode();
   219   void dump();
   220   void print(const char* name);
   221 #endif //PRODUCT
   222 };
   224 class CodeComment;
   225 class CodeComments VALUE_OBJ_CLASS_SPEC {
   226 private:
   227 #ifndef PRODUCT
   228   CodeComment* _comments;
   229 #endif
   231 public:
   232   CodeComments() {
   233 #ifndef PRODUCT
   234     _comments = NULL;
   235 #endif
   236   }
   238   void add_comment(intptr_t offset, const char * comment) PRODUCT_RETURN;
   239   void print_block_comment(outputStream* stream, intptr_t offset)  PRODUCT_RETURN;
   240   void assign(CodeComments& other)  PRODUCT_RETURN;
   241   void free() PRODUCT_RETURN;
   242 };
   245 // A CodeBuffer describes a memory space into which assembly
   246 // code is generated.  This memory space usually occupies the
   247 // interior of a single BufferBlob, but in some cases it may be
   248 // an arbitrary span of memory, even outside the code cache.
   249 //
   250 // A code buffer comes in two variants:
   251 //
   252 // (1) A CodeBuffer referring to an already allocated piece of memory:
   253 //     This is used to direct 'static' code generation (e.g. for interpreter
   254 //     or stubroutine generation, etc.).  This code comes with NO relocation
   255 //     information.
   256 //
   257 // (2) A CodeBuffer referring to a piece of memory allocated when the
   258 //     CodeBuffer is allocated.  This is used for nmethod generation.
   259 //
   260 // The memory can be divided up into several parts called sections.
   261 // Each section independently accumulates code (or data) an relocations.
   262 // Sections can grow (at the expense of a reallocation of the BufferBlob
   263 // and recopying of all active sections).  When the buffered code is finally
   264 // written to an nmethod (or other CodeBlob), the contents (code, data,
   265 // and relocations) of the sections are padded to an alignment and concatenated.
   266 // Instructions and data in one section can contain relocatable references to
   267 // addresses in a sibling section.
   269 class CodeBuffer: public StackObj {
   270   friend class CodeSection;
   272  private:
   273   // CodeBuffers must be allocated on the stack except for a single
   274   // special case during expansion which is handled internally.  This
   275   // is done to guarantee proper cleanup of resources.
   276   void* operator new(size_t size) { return ResourceObj::operator new(size); }
   277   void  operator delete(void* p)  {        ResourceObj::operator delete(p); }
   279  public:
   280   typedef int csize_t;  // code size type; would be size_t except for history
   281   enum {
   282     // Here is the list of all possible sections, in order of ascending address.
   283     SECT_INSTS,               // Executable instructions.
   284     SECT_STUBS,               // Outbound trampolines for supporting call sites.
   285     SECT_CONSTS,              // Non-instruction data:  Floats, jump tables, etc.
   286     SECT_LIMIT, SECT_NONE = -1
   287   };
   289  private:
   290   enum {
   291     sect_bits = 2,      // assert (SECT_LIMIT <= (1<<sect_bits))
   292     sect_mask = (1<<sect_bits)-1
   293   };
   295   const char*  _name;
   297   CodeSection  _insts;              // instructions (the main section)
   298   CodeSection  _stubs;              // stubs (call site support), deopt, exception handling
   299   CodeSection  _consts;             // constants, jump tables
   301   CodeBuffer*  _before_expand;  // dead buffer, from before the last expansion
   303   BufferBlob*  _blob;           // optional buffer in CodeCache for generated code
   304   address      _total_start;    // first address of combined memory buffer
   305   csize_t      _total_size;     // size in bytes of combined memory buffer
   307   OopRecorder* _oop_recorder;
   308   CodeComments _comments;
   309   OopRecorder  _default_oop_recorder;  // override with initialize_oop_recorder
   310   Arena*       _overflow_arena;
   312   address      _decode_begin;   // start address for decode
   313   address      decode_begin();
   315   void initialize_misc(const char * name) {
   316     // all pointers other than code_start/end and those inside the sections
   317     assert(name != NULL, "must have a name");
   318     _name            = name;
   319     _before_expand   = NULL;
   320     _blob            = NULL;
   321     _oop_recorder    = NULL;
   322     _decode_begin    = NULL;
   323     _overflow_arena  = NULL;
   324   }
   326   void initialize(address code_start, csize_t code_size) {
   327     _insts.initialize_outer(this,   SECT_INSTS);
   328     _stubs.initialize_outer(this,   SECT_STUBS);
   329     _consts.initialize_outer(this,  SECT_CONSTS);
   330     _total_start = code_start;
   331     _total_size  = code_size;
   332     // Initialize the main section:
   333     _insts.initialize(code_start, code_size);
   334     assert(!_stubs.is_allocated(),  "no garbage here");
   335     assert(!_consts.is_allocated(), "no garbage here");
   336     _oop_recorder = &_default_oop_recorder;
   337   }
   339   void initialize_section_size(CodeSection* cs, csize_t size);
   341   void freeze_section(CodeSection* cs);
   343   // helper for CodeBuffer::expand()
   344   void take_over_code_from(CodeBuffer* cs);
   346 #ifdef ASSERT
   347   // ensure sections are disjoint, ordered, and contained in the blob
   348   bool verify_section_allocation();
   349 #endif
   351   // copies combined relocations to the blob, returns bytes copied
   352   // (if target is null, it is a dry run only, just for sizing)
   353   csize_t copy_relocations_to(CodeBlob* blob) const;
   355   // copies combined code to the blob (assumes relocs are already in there)
   356   void copy_code_to(CodeBlob* blob);
   358   // moves code sections to new buffer (assumes relocs are already in there)
   359   void relocate_code_to(CodeBuffer* cb) const;
   361   // set up a model of the final layout of my contents
   362   void compute_final_layout(CodeBuffer* dest) const;
   364   // Expand the given section so at least 'amount' is remaining.
   365   // Creates a new, larger BufferBlob, and rewrites the code & relocs.
   366   void expand(CodeSection* which_cs, csize_t amount);
   368   // Helper for expand.
   369   csize_t figure_expanded_capacities(CodeSection* which_cs, csize_t amount, csize_t* new_capacity);
   371  public:
   372   // (1) code buffer referring to pre-allocated instruction memory
   373   CodeBuffer(address code_start, csize_t code_size);
   375   // (2) code buffer allocating codeBlob memory for code & relocation
   376   // info but with lazy initialization.  The name must be something
   377   // informative.
   378   CodeBuffer(const char* name) {
   379     initialize_misc(name);
   380   }
   383   // (3) code buffer allocating codeBlob memory for code & relocation
   384   // info.  The name must be something informative and code_size must
   385   // include both code and stubs sizes.
   386   CodeBuffer(const char* name, csize_t code_size, csize_t locs_size) {
   387     initialize_misc(name);
   388     initialize(code_size, locs_size);
   389   }
   391   ~CodeBuffer();
   393   // Initialize a CodeBuffer constructed using constructor 2.  Using
   394   // constructor 3 is equivalent to calling constructor 2 and then
   395   // calling this method.  It's been factored out for convenience of
   396   // construction.
   397   void initialize(csize_t code_size, csize_t locs_size);
   399   CodeSection* insts()             { return &_insts; }
   400   CodeSection* stubs()             { return &_stubs; }
   401   CodeSection* consts()            { return &_consts; }
   403   // present sections in order; return NULL at end; insts is #0, etc.
   404   CodeSection* code_section(int n) {
   405     // This makes the slightly questionable but portable assumption that
   406     // the various members (_insts, _stubs, etc.) are adjacent in the
   407     // layout of CodeBuffer.
   408     CodeSection* cs = &_insts + n;
   409     assert(cs->index() == n || !cs->is_allocated(), "sanity");
   410     return cs;
   411   }
   412   const CodeSection* code_section(int n) const {  // yucky const stuff
   413     return ((CodeBuffer*)this)->code_section(n);
   414   }
   415   static const char* code_section_name(int n);
   416   int section_index_of(address addr) const;
   417   bool contains(address addr) const {
   418     // handy for debugging
   419     return section_index_of(addr) > SECT_NONE;
   420   }
   422   // A stable mapping between 'locators' (small ints) and addresses.
   423   static int locator_pos(int locator)   { return locator >> sect_bits; }
   424   static int locator_sect(int locator)  { return locator &  sect_mask; }
   425   static int locator(int pos, int sect) { return (pos << sect_bits) | sect; }
   426   int        locator(address addr) const;
   427   address    locator_address(int locator) const;
   429   // Properties
   430   const char* name() const                  { return _name; }
   431   CodeBuffer* before_expand() const         { return _before_expand; }
   432   BufferBlob* blob() const                  { return _blob; }
   433   void    set_blob(BufferBlob* blob);
   434   void   free_blob();                       // Free the blob, if we own one.
   436   // Properties relative to the insts section:
   437   address code_begin() const            { return _insts.start(); }
   438   address code_end() const              { return _insts.end();   }
   439   void set_code_end(address end)        { _insts.set_end(end); }
   440   address code_limit() const            { return _insts.limit(); }
   441   address inst_mark() const             { return _insts.mark(); }
   442   void set_inst_mark()                  { _insts.set_mark(); }
   443   void clear_inst_mark()                { _insts.clear_mark(); }
   445   // is there anything in the buffer other than the current section?
   446   bool    is_pure() const               { return code_size() == total_code_size(); }
   448   // size in bytes of output so far in the insts sections
   449   csize_t code_size() const             { return _insts.size(); }
   451   // same as code_size(), except that it asserts there is no non-code here
   452   csize_t pure_code_size() const        { assert(is_pure(), "no non-code");
   453                                           return code_size(); }
   454   // capacity in bytes of the insts sections
   455   csize_t code_capacity() const         { return _insts.capacity(); }
   457   // number of bytes remaining in the insts section
   458   csize_t code_remaining() const        { return _insts.remaining(); }
   460   // is a given address in the insts section?  (2nd version is end-inclusive)
   461   bool code_contains(address pc) const  { return _insts.contains(pc); }
   462   bool code_contains2(address pc) const { return _insts.contains2(pc); }
   464   // allocated size of code in all sections, when aligned and concatenated
   465   // (this is the eventual state of the code in its final CodeBlob)
   466   csize_t total_code_size() const;
   468   // combined offset (relative to start of insts) of given address,
   469   // as eventually found in the final CodeBlob
   470   csize_t total_offset_of(address addr) const;
   472   // allocated size of all relocation data, including index, rounded up
   473   csize_t total_relocation_size() const;
   475   // allocated size of any and all recorded oops
   476   csize_t total_oop_size() const {
   477     OopRecorder* recorder = oop_recorder();
   478     return (recorder == NULL)? 0: recorder->oop_size();
   479   }
   481   // Configuration functions, called immediately after the CB is constructed.
   482   // The section sizes are subtracted from the original insts section.
   483   // Note:  Call them in reverse section order, because each steals from insts.
   484   void initialize_consts_size(csize_t size)            { initialize_section_size(&_consts,  size); }
   485   void initialize_stubs_size(csize_t size)             { initialize_section_size(&_stubs,   size); }
   486   // Override default oop recorder.
   487   void initialize_oop_recorder(OopRecorder* r);
   489   OopRecorder* oop_recorder() const   { return _oop_recorder; }
   490   CodeComments& comments()            { return _comments; }
   492   // Code generation
   493   void relocate(address at, RelocationHolder const& rspec, int format = 0) {
   494     _insts.relocate(at, rspec, format);
   495   }
   496   void relocate(address at,    relocInfo::relocType rtype, int format = 0) {
   497     _insts.relocate(at, rtype, format);
   498   }
   500   // Management of overflow storage for binding of Labels.
   501   GrowableArray<int>* create_patch_overflow();
   503   // NMethod generation
   504   void copy_code_and_locs_to(CodeBlob* blob) {
   505     assert(blob != NULL, "sane");
   506     copy_relocations_to(blob);
   507     copy_code_to(blob);
   508   }
   509   void copy_oops_to(CodeBlob* blob) {
   510     if (!oop_recorder()->is_unused()) {
   511       oop_recorder()->copy_to(blob);
   512     }
   513   }
   515   // Transform an address from the code in this code buffer to a specified code buffer
   516   address transform_address(const CodeBuffer &cb, address addr) const;
   518   void block_comment(intptr_t offset, const char * comment) PRODUCT_RETURN;
   520 #ifndef PRODUCT
   521  public:
   522   // Printing / Decoding
   523   // decodes from decode_begin() to code_end() and sets decode_begin to end
   524   void    decode();
   525   void    decode_all();         // decodes all the code
   526   void    skip_decode();        // sets decode_begin to code_end();
   527   void    print();
   528 #endif
   531   // The following header contains architecture-specific implementations
   532   #include "incls/_codeBuffer_pd.hpp.incl"
   533 };
   536 inline void CodeSection::freeze() {
   537   _outer->freeze_section(this);
   538 }
   540 inline bool CodeSection::maybe_expand_to_ensure_remaining(csize_t amount) {
   541   if (remaining() < amount) { _outer->expand(this, amount); return true; }
   542   return false;
   543 }

mercurial