hotspot/src/share/vm/oops/generateOopMap.hpp
changeset 1 489c9b5090e2
child 1374 4c24294029a9
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/oops/generateOopMap.hpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,553 @@
+/*
+ * Copyright 1997-2005 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+// Forward definition
+class MethodOopMap;
+class GenerateOopMap;
+class BasicBlock;
+class CellTypeState;
+class StackMap;
+
+// These two should be removed. But requires som code to be cleaned up
+#define MAXARGSIZE      256      // This should be enough
+#define MAX_LOCAL_VARS  65536    // 16-bit entry
+
+typedef void (*jmpFct_t)(GenerateOopMap *c, int bcpDelta, int* data);
+
+
+//  RetTable
+//
+// Contains maping between jsr targets and there return addresses. One-to-many mapping
+//
+class RetTableEntry : public ResourceObj {
+ private:
+  static int _init_nof_jsrs;                      // Default size of jsrs list
+  int _target_bci;                                // Target PC address of jump (bytecode index)
+  GrowableArray<intptr_t> * _jsrs;                     // List of return addresses  (bytecode index)
+  RetTableEntry *_next;                           // Link to next entry
+ public:
+   RetTableEntry(int target, RetTableEntry *next)  { _target_bci=target; _jsrs = new GrowableArray<intptr_t>(_init_nof_jsrs); _next = next;  }
+
+  // Query
+  int target_bci() const                      { return _target_bci; }
+  int nof_jsrs() const                        { return _jsrs->length(); }
+  int jsrs(int i) const                       { assert(i>=0 && i<nof_jsrs(), "Index out of bounds"); return _jsrs->at(i); }
+
+  // Update entry
+  void add_jsr    (int return_bci)            { _jsrs->append(return_bci); }
+  void add_delta  (int bci, int delta);
+  RetTableEntry * next()  const               { return _next; }
+};
+
+
+class RetTable VALUE_OBJ_CLASS_SPEC {
+ private:
+  RetTableEntry *_first;
+  static int _init_nof_entries;
+
+  void add_jsr(int return_bci, int target_bci);   // Adds entry to list
+ public:
+  RetTable()                                                  { _first = NULL; }
+  void compute_ret_table(methodHandle method);
+  void update_ret_table(int bci, int delta);
+  RetTableEntry* find_jsrs_for_target(int targBci);
+};
+
+//
+// CellTypeState
+//
+class CellTypeState VALUE_OBJ_CLASS_SPEC {
+ private:
+  unsigned int _state;
+
+  // Masks for separating the BITS and INFO portions of a CellTypeState
+  enum { info_mask            = right_n_bits(28),
+         bits_mask            = (int)(~info_mask) };
+
+  // These constant are used for manipulating the BITS portion of a
+  // CellTypeState
+  enum { uninit_bit           = (int)(nth_bit(31)),
+         ref_bit              = nth_bit(30),
+         val_bit              = nth_bit(29),
+         addr_bit             = nth_bit(28),
+         live_bits_mask       = (int)(bits_mask & ~uninit_bit) };
+
+  // These constants are used for manipulating the INFO portion of a
+  // CellTypeState
+  enum { top_info_bit         = nth_bit(27),
+         not_bottom_info_bit  = nth_bit(26),
+         info_data_mask       = right_n_bits(26),
+         info_conflict        = info_mask };
+
+  // Within the INFO data, these values are used to distinguish different
+  // kinds of references.
+  enum { ref_not_lock_bit     = nth_bit(25),  // 0 if this reference is locked as a monitor
+         ref_slot_bit         = nth_bit(24),  // 1 if this reference is a "slot" reference,
+                                              // 0 if it is a "line" reference.
+         ref_data_mask        = right_n_bits(24) };
+
+
+  // These values are used to initialize commonly used CellTypeState
+  // constants.
+  enum { bottom_value         = 0,
+         uninit_value         = (int)(uninit_bit | info_conflict),
+         ref_value            = ref_bit,
+         ref_conflict         = ref_bit | info_conflict,
+         val_value            = val_bit | info_conflict,
+         addr_value           = addr_bit,
+         addr_conflict        = addr_bit | info_conflict };
+
+ public:
+
+  // Since some C++ constructors generate poor code for declarations of the
+  // form...
+  //
+  //   CellTypeState vector[length];
+  //
+  // ...we avoid making a constructor for this class.  CellTypeState values
+  // should be constructed using one of the make_* methods:
+
+  static CellTypeState make_any(int state) {
+    CellTypeState s;
+    s._state = state;
+    // Causes SS10 warning.
+    // assert(s.is_valid_state(), "check to see if CellTypeState is valid");
+    return s;
+  }
+
+  static CellTypeState make_bottom() {
+    return make_any(0);
+  }
+
+  static CellTypeState make_top() {
+    return make_any(AllBits);
+  }
+
+  static CellTypeState make_addr(int bci) {
+    assert((bci >= 0) && (bci < info_data_mask), "check to see if ret addr is valid");
+    return make_any(addr_bit | not_bottom_info_bit | (bci & info_data_mask));
+  }
+
+  static CellTypeState make_slot_ref(int slot_num) {
+    assert(slot_num >= 0 && slot_num < ref_data_mask, "slot out of range");
+    return make_any(ref_bit | not_bottom_info_bit | ref_not_lock_bit | ref_slot_bit |
+                    (slot_num & ref_data_mask));
+  }
+
+  static CellTypeState make_line_ref(int bci) {
+    assert(bci >= 0 && bci < ref_data_mask, "line out of range");
+    return make_any(ref_bit | not_bottom_info_bit | ref_not_lock_bit |
+                    (bci & ref_data_mask));
+  }
+
+  static CellTypeState make_lock_ref(int bci) {
+    assert(bci >= 0 && bci < ref_data_mask, "line out of range");
+    return make_any(ref_bit | not_bottom_info_bit | (bci & ref_data_mask));
+  }
+
+  // Query methods:
+  bool is_bottom() const                { return _state == 0; }
+  bool is_live() const                  { return ((_state & live_bits_mask) != 0); }
+  bool is_valid_state() const {
+    // Uninitialized and value cells must contain no data in their info field:
+    if ((can_be_uninit() || can_be_value()) && !is_info_top()) {
+      return false;
+    }
+    // The top bit is only set when all info bits are set:
+    if (is_info_top() && ((_state & info_mask) != info_mask)) {
+      return false;
+    }
+    // The not_bottom_bit must be set when any other info bit is set:
+    if (is_info_bottom() && ((_state & info_mask) != 0)) {
+      return false;
+    }
+    return true;
+  }
+
+  bool is_address() const               { return ((_state & bits_mask) == addr_bit); }
+  bool is_reference() const             { return ((_state & bits_mask) == ref_bit); }
+  bool is_value() const                 { return ((_state & bits_mask) == val_bit); }
+  bool is_uninit() const                { return ((_state & bits_mask) == (uint)uninit_bit); }
+
+  bool can_be_address() const           { return ((_state & addr_bit) != 0); }
+  bool can_be_reference() const         { return ((_state & ref_bit) != 0); }
+  bool can_be_value() const             { return ((_state & val_bit) != 0); }
+  bool can_be_uninit() const            { return ((_state & uninit_bit) != 0); }
+
+  bool is_info_bottom() const           { return ((_state & not_bottom_info_bit) == 0); }
+  bool is_info_top() const              { return ((_state & top_info_bit) != 0); }
+  int  get_info() const {
+    assert((!is_info_top() && !is_info_bottom()),
+           "check to make sure top/bottom info is not used");
+    return (_state & info_data_mask);
+  }
+
+  bool is_good_address() const          { return is_address() && !is_info_top(); }
+  bool is_lock_reference() const {
+    return ((_state & (bits_mask | top_info_bit | ref_not_lock_bit)) == ref_bit);
+  }
+  bool is_nonlock_reference() const {
+    return ((_state & (bits_mask | top_info_bit | ref_not_lock_bit)) == (ref_bit | ref_not_lock_bit));
+  }
+
+  bool equal(CellTypeState a) const     { return _state == a._state; }
+  bool equal_kind(CellTypeState a) const {
+    return (_state & bits_mask) == (a._state & bits_mask);
+  }
+
+  char to_char() const;
+
+  // Merge
+  CellTypeState merge (CellTypeState cts, int slot) const;
+
+  // Debugging output
+  void print(outputStream *os);
+
+  // Default values of common values
+  static CellTypeState bottom;
+  static CellTypeState uninit;
+  static CellTypeState ref;
+  static CellTypeState value;
+  static CellTypeState refUninit;
+  static CellTypeState varUninit;
+  static CellTypeState top;
+  static CellTypeState addr;
+};
+
+
+//
+// BasicBlockStruct
+//
+class BasicBlock: ResourceObj {
+ private:
+  bool            _changed;                 // Reached a fixpoint or not
+ public:
+  enum Constants {
+    _dead_basic_block = -2,
+    _unreached        = -1                  // Alive but not yet reached by analysis
+    // >=0                                  // Alive and has a merged state
+  };
+
+  int             _bci;                     // Start of basic block
+  int             _end_bci;                 // Bci of last instruction in basicblock
+  int             _max_locals;              // Determines split between vars and stack
+  int             _max_stack;               // Determines split between stack and monitors
+  CellTypeState*  _state;                   // State (vars, stack) at entry.
+  int             _stack_top;               // -1 indicates bottom stack value.
+  int             _monitor_top;             // -1 indicates bottom monitor stack value.
+
+  CellTypeState* vars()                     { return _state; }
+  CellTypeState* stack()                    { return _state + _max_locals; }
+
+  bool changed()                            { return _changed; }
+  void set_changed(bool s)                  { _changed = s; }
+
+  bool is_reachable() const                 { return _stack_top >= 0; }  // Analysis has reached this basicblock
+
+  // All basicblocks that are unreachable are going to have a _stack_top == _dead_basic_block.
+  // This info. is setup in a pre-parse before the real abstract interpretation starts.
+  bool is_dead() const                      { return _stack_top == _dead_basic_block; }
+  bool is_alive() const                     { return _stack_top != _dead_basic_block; }
+  void mark_as_alive()                      { assert(is_dead(), "must be dead"); _stack_top = _unreached; }
+};
+
+
+//
+//  GenerateOopMap
+//
+// Main class used to compute the pointer-maps in a MethodOop
+//
+class GenerateOopMap VALUE_OBJ_CLASS_SPEC {
+ protected:
+
+  // _monitor_top is set to this constant to indicate that a monitor matching
+  // problem was encountered prior to this point in control flow.
+  enum { bad_monitors = -1 };
+
+  // Main variables
+  methodHandle _method;                     // The method we are examine
+  RetTable     _rt;                         // Contains the return address mappings
+  int          _max_locals;                 // Cached value of no. of locals
+  int          _max_stack;                  // Cached value of max. stack depth
+  int          _max_monitors;               // Cached value of max. monitor stack depth
+  int          _has_exceptions;             // True, if exceptions exist for method
+  bool         _got_error;                  // True, if an error occured during interpretation.
+  Handle       _exception;                  // Exception if got_error is true.
+  bool         _did_rewriting;              // was bytecodes rewritten
+  bool         _did_relocation;             // was relocation neccessary
+  bool         _monitor_safe;               // The monitors in this method have been determined
+                                            // to be safe.
+
+  // Working Cell type state
+  int            _state_len;                // Size of states
+  CellTypeState *_state;                    // list of states
+  char          *_state_vec_buf;            // Buffer used to print a readable version of a state
+  int            _stack_top;
+  int            _monitor_top;
+
+  // Timing and statistics
+  static elapsedTimer _total_oopmap_time;   // Holds cumulative oopmap generation time
+  static long         _total_byte_count;    // Holds cumulative number of bytes inspected
+
+  // Cell type methods
+  void            init_state();
+  void            make_context_uninitialized ();
+  int             methodsig_to_effect        (symbolOop signature, bool isStatic, CellTypeState* effect);
+  bool            merge_local_state_vectors  (CellTypeState* cts, CellTypeState* bbts);
+  bool            merge_monitor_state_vectors(CellTypeState* cts, CellTypeState* bbts);
+  void            copy_state                 (CellTypeState *dst, CellTypeState *src);
+  void            merge_state_into_bb        (BasicBlock *bb);
+  static void     merge_state                (GenerateOopMap *gom, int bcidelta, int* data);
+  void            set_var                    (int localNo, CellTypeState cts);
+  CellTypeState   get_var                    (int localNo);
+  CellTypeState   pop                        ();
+  void            push                       (CellTypeState cts);
+  CellTypeState   monitor_pop                ();
+  void            monitor_push               (CellTypeState cts);
+  CellTypeState * vars                       ()                                             { return _state; }
+  CellTypeState * stack                      ()                                             { return _state+_max_locals; }
+  CellTypeState * monitors                   ()                                             { return _state+_max_locals+_max_stack; }
+
+  void            replace_all_CTS_matches    (CellTypeState match,
+                                              CellTypeState replace);
+  void            print_states               (outputStream *os, CellTypeState *vector, int num);
+  void            print_current_state        (outputStream   *os,
+                                              BytecodeStream *itr,
+                                              bool            detailed);
+  void            report_monitor_mismatch    (const char *msg);
+
+  // Basicblock info
+  BasicBlock *    _basic_blocks;             // Array of basicblock info
+  int             _gc_points;
+  int             _bb_count;
+  uintptr_t *     _bb_hdr_bits;
+
+  // Basicblocks methods
+  void          initialize_bb               ();
+  void          mark_bbheaders_and_count_gc_points();
+  bool          is_bb_header                (int bci) const   { return (_bb_hdr_bits[bci >> LogBitsPerWord] & ((uintptr_t)1 << (bci & (BitsPerWord-1)))) != 0; }
+  int           gc_points                   () const                          { return _gc_points; }
+  int           bb_count                    () const                          { return _bb_count; }
+  void          set_bbmark_bit              (int bci);
+  void          clear_bbmark_bit            (int bci);
+  BasicBlock *  get_basic_block_at          (int bci) const;
+  BasicBlock *  get_basic_block_containing  (int bci) const;
+  void          interp_bb                   (BasicBlock *bb);
+  void          restore_state               (BasicBlock *bb);
+  int           next_bb_start_pc            (BasicBlock *bb);
+  void          update_basic_blocks         (int bci, int delta, int new_method_size);
+  static void   bb_mark_fct                 (GenerateOopMap *c, int deltaBci, int *data);
+
+  // Dead code detection
+  void          mark_reachable_code();
+  static void   reachable_basicblock        (GenerateOopMap *c, int deltaBci, int *data);
+
+  // Interpretation methods (primary)
+  void  do_interpretation                   ();
+  void  init_basic_blocks                   ();
+  void  setup_method_entry_state            ();
+  void  interp_all                          ();
+
+  // Interpretation methods (secondary)
+  void  interp1                             (BytecodeStream *itr);
+  void  do_exception_edge                   (BytecodeStream *itr);
+  void  check_type                          (CellTypeState expected, CellTypeState actual);
+  void  ppstore                             (CellTypeState *in,  int loc_no);
+  void  ppload                              (CellTypeState *out, int loc_no);
+  void  ppush1                              (CellTypeState in);
+  void  ppush                               (CellTypeState *in);
+  void  ppop1                               (CellTypeState out);
+  void  ppop                                (CellTypeState *out);
+  void  ppop_any                            (int poplen);
+  void  pp                                  (CellTypeState *in, CellTypeState *out);
+  void  pp_new_ref                          (CellTypeState *in, int bci);
+  void  ppdupswap                           (int poplen, const char *out);
+  void  do_ldc                              (int idx, int bci);
+  void  do_astore                           (int idx);
+  void  do_jsr                              (int delta);
+  void  do_field                            (int is_get, int is_static, int idx, int bci);
+  void  do_method                           (int is_static, int is_interface, int idx, int bci);
+  void  do_multianewarray                   (int dims, int bci);
+  void  do_monitorenter                     (int bci);
+  void  do_monitorexit                      (int bci);
+  void  do_return_monitor_check             ();
+  void  do_checkcast                        ();
+  CellTypeState *sigchar_to_effect          (char sigch, int bci, CellTypeState *out);
+  int copy_cts                              (CellTypeState *dst, CellTypeState *src);
+
+  // Error handling
+  void  error_work                          (const char *format, va_list ap);
+  void  report_error                        (const char *format, ...);
+  void  verify_error                        (const char *format, ...);
+  bool  got_error()                         { return _got_error; }
+
+  // Create result set
+  bool  _report_result;
+  bool  _report_result_for_send;            // Unfortunatly, stackmaps for sends are special, so we need some extra
+  BytecodeStream *_itr_send;                // variables to handle them properly.
+
+  void  report_result                       ();
+
+  // Initvars
+  GrowableArray<intptr_t> * _init_vars;
+
+  void  initialize_vars                     ();
+  void  add_to_ref_init_set                 (int localNo);
+
+  // Conflicts rewrite logic
+  bool      _conflict;                      // True, if a conflict occured during interpretation
+  int       _nof_refval_conflicts;          // No. of conflicts that require rewrites
+  int *     _new_var_map;
+
+  void record_refval_conflict               (int varNo);
+  void rewrite_refval_conflicts             ();
+  void rewrite_refval_conflict              (int from, int to);
+  bool rewrite_refval_conflict_inst         (BytecodeStream *i, int from, int to);
+  bool rewrite_load_or_store                (BytecodeStream *i, Bytecodes::Code bc, Bytecodes::Code bc0, unsigned int varNo);
+
+  void expand_current_instr                 (int bci, int ilen, int newIlen, u_char inst_buffer[]);
+  bool is_astore                            (BytecodeStream *itr, int *index);
+  bool is_aload                             (BytecodeStream *itr, int *index);
+
+  // List of bci's where a return address is on top of the stack
+  GrowableArray<intptr_t> *_ret_adr_tos;
+
+  bool stack_top_holds_ret_addr             (int bci);
+  void compute_ret_adr_at_TOS               ();
+  void update_ret_adr_at_TOS                (int bci, int delta);
+
+  int  binsToHold                           (int no)                      { return  ((no+(BitsPerWord-1))/BitsPerWord); }
+  char *state_vec_to_string                 (CellTypeState* vec, int len);
+
+  // Helper method. Can be used in subclasses to fx. calculate gc_points. If the current instuction
+  // is a control transfer, then calls the jmpFct all possible destinations.
+  void  ret_jump_targets_do                 (BytecodeStream *bcs, jmpFct_t jmpFct, int varNo,int *data);
+  bool  jump_targets_do                     (BytecodeStream *bcs, jmpFct_t jmpFct, int *data);
+
+  friend class RelocCallback;
+ public:
+  GenerateOopMap(methodHandle method);
+
+  // Compute the map.
+  void compute_map(TRAPS);
+  void result_for_basicblock(int bci);    // Do a callback on fill_stackmap_for_opcodes for basicblock containing bci
+
+  // Query
+  int max_locals() const                           { return _max_locals; }
+  methodOop method() const                         { return _method(); }
+  methodHandle method_as_handle() const            { return _method; }
+
+  bool did_rewriting()                             { return _did_rewriting; }
+  bool did_relocation()                            { return _did_relocation; }
+
+  static void print_time();
+
+  // Monitor query
+  bool monitor_safe()                              { return _monitor_safe; }
+
+  // Specialization methods. Intended use:
+  // - possible_gc_point must return true for every bci for which the stackmaps must be returned
+  // - fill_stackmap_prolog is called just before the result is reported. The arguments tells the estimated
+  //   number of gc points
+  // - fill_stackmap_for_opcodes is called once for each bytecode index in order (0...code_length-1)
+  // - fill_stackmap_epilog is called after all results has been reported. Note: Since the algorithm does not report
+  //   stackmaps for deadcode, fewer gc_points might have been encounted than assumed during the epilog. It is the
+  //   responsibility of the subclass to count the correct number.
+  // - fill_init_vars are called once with the result of the init_vars computation
+  //
+  // All these methods are used during a call to: compute_map. Note: Non of the return results are valid
+  // after compute_map returns, since all values are allocated as resource objects.
+  //
+  // All virtual method must be implemented in subclasses
+  virtual bool allow_rewrites             () const                        { return false; }
+  virtual bool report_results             () const                        { return true;  }
+  virtual bool report_init_vars           () const                        { return true;  }
+  virtual bool possible_gc_point          (BytecodeStream *bcs)           { ShouldNotReachHere(); return false; }
+  virtual void fill_stackmap_prolog       (int nof_gc_points)             { ShouldNotReachHere(); }
+  virtual void fill_stackmap_epilog       ()                              { ShouldNotReachHere(); }
+  virtual void fill_stackmap_for_opcodes  (BytecodeStream *bcs,
+                                           CellTypeState* vars,
+                                           CellTypeState* stack,
+                                           int stackTop)                  { ShouldNotReachHere(); }
+  virtual void fill_init_vars             (GrowableArray<intptr_t> *init_vars) { ShouldNotReachHere();; }
+};
+
+//
+// Subclass of the GenerateOopMap Class that just do rewrites of the method, if needed.
+// It does not store any oopmaps.
+//
+class ResolveOopMapConflicts: public GenerateOopMap {
+ private:
+
+  bool _must_clear_locals;
+
+  virtual bool report_results() const     { return false; }
+  virtual bool report_init_vars() const   { return true;  }
+  virtual bool allow_rewrites() const     { return true;  }
+  virtual bool possible_gc_point          (BytecodeStream *bcs)           { return false; }
+  virtual void fill_stackmap_prolog       (int nof_gc_points)             {}
+  virtual void fill_stackmap_epilog       ()                              {}
+  virtual void fill_stackmap_for_opcodes  (BytecodeStream *bcs,
+                                           CellTypeState* vars,
+                                           CellTypeState* stack,
+                                           int stack_top)                 {}
+  virtual void fill_init_vars             (GrowableArray<intptr_t> *init_vars) { _must_clear_locals = init_vars->length() > 0; }
+
+#ifndef PRODUCT
+  // Statistics
+  static int _nof_invocations;
+  static int _nof_rewrites;
+  static int _nof_relocations;
+#endif
+
+ public:
+  ResolveOopMapConflicts(methodHandle method) : GenerateOopMap(method) { _must_clear_locals = false; };
+
+  methodHandle do_potential_rewrite(TRAPS);
+  bool must_clear_locals() const { return _must_clear_locals; }
+};
+
+
+//
+// Subclass used by the compiler to generate pairing infomation
+//
+class GeneratePairingInfo: public GenerateOopMap {
+ private:
+
+  virtual bool report_results() const     { return false; }
+  virtual bool report_init_vars() const   { return false; }
+  virtual bool allow_rewrites() const     { return false;  }
+  virtual bool possible_gc_point          (BytecodeStream *bcs)           { return false; }
+  virtual void fill_stackmap_prolog       (int nof_gc_points)             {}
+  virtual void fill_stackmap_epilog       ()                              {}
+  virtual void fill_stackmap_for_opcodes  (BytecodeStream *bcs,
+                                           CellTypeState* vars,
+                                           CellTypeState* stack,
+                                           int stack_top)                 {}
+  virtual void fill_init_vars             (GrowableArray<intptr_t> *init_vars) {}
+ public:
+  GeneratePairingInfo(methodHandle method) : GenerateOopMap(method)       {};
+
+  // Call compute_map(CHECK) to generate info.
+};