src/share/vm/opto/parse.hpp

Fri, 08 Jan 2010 13:58:49 -0800

author
jrose
date
Fri, 08 Jan 2010 13:58:49 -0800
changeset 1592
c3b315a0d58a
parent 1424
148e5441d916
child 1607
b2b6a9bf6238
permissions
-rw-r--r--

6912063: inlining parameters need to be adjusted for some uses of the JVM
Summary: Put all inline-related switches into product mode, to allow tuning by dynamic language implementors.
Reviewed-by: twisti, kvn

     1 /*
     2  * Copyright 1997-2009 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  */
    25 class BytecodeParseHistogram;
    26 class InlineTree;
    27 class Parse;
    28 class SwitchRange;
    31 //------------------------------InlineTree-------------------------------------
    32 class InlineTree : public ResourceObj {
    33   Compile*    C;                  // cache
    34   JVMState*   _caller_jvms;       // state of caller
    35   ciMethod*   _method;            // method being called by the caller_jvms
    36   InlineTree* _caller_tree;
    37   uint        _count_inline_bcs;  // Accumulated count of inlined bytecodes
    38   // Call-site count / interpreter invocation count, scaled recursively.
    39   // Always between 0.0 and 1.0.  Represents the percentage of the method's
    40   // total execution time used at this call site.
    41   const float _site_invoke_ratio;
    42   const int   _site_depth_adjust;
    43   float compute_callee_frequency( int caller_bci ) const;
    45   GrowableArray<InlineTree*> _subtrees;
    46   friend class Compile;
    48 protected:
    49   InlineTree(Compile* C,
    50              const InlineTree* caller_tree,
    51              ciMethod* callee_method,
    52              JVMState* caller_jvms,
    53              int caller_bci,
    54              float site_invoke_ratio,
    55              int site_depth_adjust);
    56   InlineTree *build_inline_tree_for_callee(ciMethod* callee_method,
    57                                            JVMState* caller_jvms,
    58                                            int caller_bci);
    59   const char* try_to_inline(ciMethod* callee_method, ciMethod* caller_method, int caller_bci, ciCallProfile& profile, WarmCallInfo* wci_result);
    60   const char* shouldInline(ciMethod* callee_method, ciMethod* caller_method, int caller_bci, ciCallProfile& profile, WarmCallInfo* wci_result) const;
    61   const char* shouldNotInline(ciMethod* callee_method, ciMethod* caller_method, WarmCallInfo* wci_result) const;
    62   void        print_inlining(ciMethod *callee_method, int caller_bci, const char *failure_msg) const PRODUCT_RETURN;
    64   InlineTree *caller_tree()       const { return _caller_tree;  }
    65   InlineTree* callee_at(int bci, ciMethod* m) const;
    66   int         inline_depth()      const { return stack_depth() + _site_depth_adjust; }
    67   int         stack_depth()       const { return _caller_jvms ? _caller_jvms->depth() : 0; }
    69 public:
    70   static InlineTree* build_inline_tree_root();
    71   static InlineTree* find_subtree_from_root(InlineTree* root, JVMState* jvms, ciMethod* callee, bool create_if_not_found = false);
    73   // For temporary (stack-allocated, stateless) ilts:
    74   InlineTree(Compile* c, ciMethod* callee_method, JVMState* caller_jvms, float site_invoke_ratio, int site_depth_adjust);
    76   // InlineTree enum
    77   enum InlineStyle {
    78     Inline_do_not_inline             =   0, //
    79     Inline_cha_is_monomorphic        =   1, //
    80     Inline_type_profile_monomorphic  =   2  //
    81   };
    83   // See if it is OK to inline.
    84   // The receiver is the inline tree for the caller.
    85   //
    86   // The result is a temperature indication.  If it is hot or cold,
    87   // inlining is immediate or undesirable.  Otherwise, the info block
    88   // returned is newly allocated and may be enqueued.
    89   //
    90   // If the method is inlinable, a new inline subtree is created on the fly,
    91   // and may be accessed by find_subtree_from_root.
    92   // The call_method is the dest_method for a special or static invocation.
    93   // The call_method is an optimized virtual method candidate otherwise.
    94   WarmCallInfo* ok_to_inline(ciMethod *call_method, JVMState* caller_jvms, ciCallProfile& profile, WarmCallInfo* wci);
    96   // Information about inlined method
    97   JVMState*   caller_jvms()       const { return _caller_jvms; }
    98   ciMethod   *method()            const { return _method; }
    99   int         caller_bci()        const { return _caller_jvms ? _caller_jvms->bci() : InvocationEntryBci; }
   100   uint        count_inline_bcs()  const { return _count_inline_bcs; }
   101   float       site_invoke_ratio() const { return _site_invoke_ratio; };
   103 #ifndef PRODUCT
   104 private:
   105   uint        _count_inlines;     // Count of inlined methods
   106 public:
   107   // Debug information collected during parse
   108   uint        count_inlines()     const { return _count_inlines; };
   109 #endif
   110   GrowableArray<InlineTree*> subtrees() { return _subtrees; }
   111 };
   114 //-----------------------------------------------------------------------------
   115 //------------------------------Parse------------------------------------------
   116 // Parse bytecodes, build a Graph
   117 class Parse : public GraphKit {
   118  public:
   119   // Per-block information needed by the parser:
   120   class Block {
   121    private:
   122     ciTypeFlow::Block* _flow;
   123     int                _pred_count;     // how many predecessors in CFG?
   124     int                _preds_parsed;   // how many of these have been parsed?
   125     uint               _count;          // how many times executed?  Currently only set by _goto's
   126     bool               _is_parsed;      // has this block been parsed yet?
   127     bool               _is_handler;     // is this block an exception handler?
   128     SafePointNode*     _start_map;      // all values flowing into this block
   129     MethodLivenessResult _live_locals;  // lazily initialized liveness bitmap
   131     int                _num_successors; // Includes only normal control flow.
   132     int                _all_successors; // Include exception paths also.
   133     Block**            _successors;
   135     // Use init_node/init_graph to initialize Blocks.
   136     // Block() : _live_locals((uintptr_t*)NULL,0) { ShouldNotReachHere(); }
   137     Block() : _live_locals(NULL,0) { ShouldNotReachHere(); }
   139    public:
   141     // Set up the block data structure itself.
   142     void init_node(Parse* outer, int po);
   143     // Set up the block's relations to other blocks.
   144     void init_graph(Parse* outer);
   146     ciTypeFlow::Block* flow() const        { return _flow; }
   147     int pred_count() const                 { return _pred_count; }
   148     int preds_parsed() const               { return _preds_parsed; }
   149     bool is_parsed() const                 { return _is_parsed; }
   150     bool is_handler() const                { return _is_handler; }
   151     void set_count( uint x )               { _count = x; }
   152     uint count() const                     { return _count; }
   154     SafePointNode* start_map() const       { assert(is_merged(),"");   return _start_map; }
   155     void set_start_map(SafePointNode* m)   { assert(!is_merged(), ""); _start_map = m; }
   157     // True after any predecessor flows control into this block
   158     bool is_merged() const                 { return _start_map != NULL; }
   160     // True when all non-exception predecessors have been parsed.
   161     bool is_ready() const                  { return preds_parsed() == pred_count(); }
   163     int num_successors() const             { return _num_successors; }
   164     int all_successors() const             { return _all_successors; }
   165     Block* successor_at(int i) const {
   166       assert((uint)i < (uint)all_successors(), "");
   167       return _successors[i];
   168     }
   169     Block* successor_for_bci(int bci);
   171     int start() const                      { return flow()->start(); }
   172     int limit() const                      { return flow()->limit(); }
   173     int rpo() const                        { return flow()->rpo(); }
   174     int start_sp() const                   { return flow()->stack_size(); }
   176     bool is_loop_head() const              { return flow()->is_loop_head(); }
   177     bool is_SEL_head() const               { return flow()->is_single_entry_loop_head(); }
   178     bool is_SEL_backedge(Block* pred) const{ return is_SEL_head() && pred->rpo() >= rpo(); }
   179     bool is_invariant_local(uint i) const  {
   180       const JVMState* jvms = start_map()->jvms();
   181       if (!jvms->is_loc(i) || flow()->outer()->has_irreducible_entry()) return false;
   182       return flow()->is_invariant_local(i - jvms->locoff());
   183     }
   184     bool can_elide_SEL_phi(uint i) const  { assert(is_SEL_head(),""); return is_invariant_local(i); }
   186     const Type* peek(int off=0) const      { return stack_type_at(start_sp() - (off+1)); }
   188     const Type* stack_type_at(int i) const;
   189     const Type* local_type_at(int i) const;
   190     static const Type* get_type(ciType* t) { return Type::get_typeflow_type(t); }
   192     bool has_trap_at(int bci) const        { return flow()->has_trap() && flow()->trap_bci() == bci; }
   194     // Call this just before parsing a block.
   195     void mark_parsed() {
   196       assert(!_is_parsed, "must parse each block exactly once");
   197       _is_parsed = true;
   198     }
   200     // Return the phi/region input index for the "current" pred,
   201     // and bump the pred number.  For historical reasons these index
   202     // numbers are handed out in descending order.  The last index is
   203     // always PhiNode::Input (i.e., 1).  The value returned is known
   204     // as a "path number" because it distinguishes by which path we are
   205     // entering the block.
   206     int next_path_num() {
   207       assert(preds_parsed() < pred_count(), "too many preds?");
   208       return pred_count() - _preds_parsed++;
   209     }
   211     // Add a previously unaccounted predecessor to this block.
   212     // This operates by increasing the size of the block's region
   213     // and all its phi nodes (if any).  The value returned is a
   214     // path number ("pnum").
   215     int add_new_path();
   217     // Initialize me by recording the parser's map.  My own map must be NULL.
   218     void record_state(Parse* outer);
   219   };
   221 #ifndef PRODUCT
   222   // BytecodeParseHistogram collects number of bytecodes parsed, nodes constructed, and transformations.
   223   class BytecodeParseHistogram : public ResourceObj {
   224    private:
   225     enum BPHType {
   226       BPH_transforms,
   227       BPH_values
   228     };
   229     static bool _initialized;
   230     static uint _bytecodes_parsed [Bytecodes::number_of_codes];
   231     static uint _nodes_constructed[Bytecodes::number_of_codes];
   232     static uint _nodes_transformed[Bytecodes::number_of_codes];
   233     static uint _new_values       [Bytecodes::number_of_codes];
   235     Bytecodes::Code _initial_bytecode;
   236     int             _initial_node_count;
   237     int             _initial_transforms;
   238     int             _initial_values;
   240     Parse     *_parser;
   241     Compile   *_compiler;
   243     // Initialization
   244     static void reset();
   246     // Return info being collected, select with global flag 'BytecodeParseInfo'
   247     int current_count(BPHType info_selector);
   249    public:
   250     BytecodeParseHistogram(Parse *p, Compile *c);
   251     static bool initialized();
   253     // Record info when starting to parse one bytecode
   254     void set_initial_state( Bytecodes::Code bc );
   255     // Record results of parsing one bytecode
   256     void record_change();
   258     // Profile printing
   259     static void print(float cutoff = 0.01F); // cutoff in percent
   260   };
   262   public:
   263     // Record work done during parsing
   264     BytecodeParseHistogram* _parse_histogram;
   265     void set_parse_histogram(BytecodeParseHistogram *bph) { _parse_histogram = bph; }
   266     BytecodeParseHistogram* parse_histogram()      { return _parse_histogram; }
   267 #endif
   269  private:
   270   friend class Block;
   272   // Variables which characterize this compilation as a whole:
   274   JVMState*     _caller;        // JVMS which carries incoming args & state.
   275   float         _expected_uses; // expected number of calls to this code
   276   float         _prof_factor;   // discount applied to my profile counts
   277   int           _depth;         // Inline tree depth, for debug printouts
   278   const TypeFunc*_tf;           // My kind of function type
   279   int           _entry_bci;     // the osr bci or InvocationEntryBci
   281   ciTypeFlow*   _flow;          // Results of previous flow pass.
   282   Block*        _blocks;        // Array of basic-block structs.
   283   int           _block_count;   // Number of elements in _blocks.
   285   GraphKit      _exits;         // Record all normal returns and throws here.
   286   bool          _wrote_final;   // Did we write a final field?
   287   bool          _count_invocations; // update and test invocation counter
   288   bool          _method_data_update; // update method data oop
   290   // Variables which track Java semantics during bytecode parsing:
   292   Block*            _block;     // block currently getting parsed
   293   ciBytecodeStream  _iter;      // stream of this method's bytecodes
   295   int           _blocks_merged; // Progress meter: state merges from BB preds
   296   int           _blocks_parsed; // Progress meter: BBs actually parsed
   298   const FastLockNode* _synch_lock; // FastLockNode for synchronized method
   300 #ifndef PRODUCT
   301   int _max_switch_depth;        // Debugging SwitchRanges.
   302   int _est_switch_depth;        // Debugging SwitchRanges.
   303 #endif
   305  public:
   306   // Constructor
   307   Parse(JVMState* caller, ciMethod* parse_method, float expected_uses);
   309   virtual Parse* is_Parse() const { return (Parse*)this; }
   311  public:
   312   // Accessors.
   313   JVMState*     caller()        const { return _caller; }
   314   float         expected_uses() const { return _expected_uses; }
   315   float         prof_factor()   const { return _prof_factor; }
   316   int           depth()         const { return _depth; }
   317   const TypeFunc* tf()          const { return _tf; }
   318   //            entry_bci()     -- see osr_bci, etc.
   320   ciTypeFlow*   flow()          const { return _flow; }
   321   //            blocks()        -- see rpo_at, start_block, etc.
   322   int           block_count()   const { return _block_count; }
   324   GraphKit&     exits()               { return _exits; }
   325   bool          wrote_final() const   { return _wrote_final; }
   326   void      set_wrote_final(bool z)   { _wrote_final = z; }
   327   bool          count_invocations() const  { return _count_invocations; }
   328   bool          method_data_update() const { return _method_data_update; }
   330   Block*             block()    const { return _block; }
   331   ciBytecodeStream&  iter()           { return _iter; }
   332   Bytecodes::Code    bc()       const { return _iter.cur_bc(); }
   334   void set_block(Block* b)            { _block = b; }
   336   // Derived accessors:
   337   bool is_normal_parse() const  { return _entry_bci == InvocationEntryBci; }
   338   bool is_osr_parse() const     { return _entry_bci != InvocationEntryBci; }
   339   int osr_bci() const           { assert(is_osr_parse(),""); return _entry_bci; }
   341   void set_parse_bci(int bci);
   343   // Must this parse be aborted?
   344   bool failing()                { return C->failing(); }
   346   Block* rpo_at(int rpo) {
   347     assert(0 <= rpo && rpo < _block_count, "oob");
   348     return &_blocks[rpo];
   349   }
   350   Block* start_block() {
   351     return rpo_at(flow()->start_block()->rpo());
   352   }
   353   // Can return NULL if the flow pass did not complete a block.
   354   Block* successor_for_bci(int bci) {
   355     return block()->successor_for_bci(bci);
   356   }
   358  private:
   359   // Create a JVMS & map for the initial state of this method.
   360   SafePointNode* create_entry_map();
   362   // OSR helpers
   363   Node *fetch_interpreter_state(int index, BasicType bt, Node *local_addrs, Node *local_addrs_base);
   364   Node* check_interpreter_type(Node* l, const Type* type, SafePointNode* &bad_type_exit);
   365   void  load_interpreter_state(Node* osr_buf);
   367   // Functions for managing basic blocks:
   368   void init_blocks();
   369   void load_state_from(Block* b);
   370   void store_state_to(Block* b) { b->record_state(this); }
   372   // Parse all the basic blocks.
   373   void do_all_blocks();
   375   // Parse the current basic block
   376   void do_one_block();
   378   // Raise an error if we get a bad ciTypeFlow CFG.
   379   void handle_missing_successor(int bci);
   381   // first actions (before BCI 0)
   382   void do_method_entry();
   384   // implementation of monitorenter/monitorexit
   385   void do_monitor_enter();
   386   void do_monitor_exit();
   388   // Eagerly create phie throughout the state, to cope with back edges.
   389   void ensure_phis_everywhere();
   391   // Merge the current mapping into the basic block starting at bci
   392   void merge(          int target_bci);
   393   // Same as plain merge, except that it allocates a new path number.
   394   void merge_new_path( int target_bci);
   395   // Merge the current mapping into an exception handler.
   396   void merge_exception(int target_bci);
   397   // Helper: Merge the current mapping into the given basic block
   398   void merge_common(Block* target, int pnum);
   399   // Helper functions for merging individual cells.
   400   PhiNode *ensure_phi(       int idx, bool nocreate = false);
   401   PhiNode *ensure_memory_phi(int idx, bool nocreate = false);
   402   // Helper to merge the current memory state into the given basic block
   403   void merge_memory_edges(MergeMemNode* n, int pnum, bool nophi);
   405   // Parse this bytecode, and alter the Parsers JVM->Node mapping
   406   void do_one_bytecode();
   408   // helper function to generate array store check
   409   void array_store_check();
   410   // Helper function to generate array load
   411   void array_load(BasicType etype);
   412   // Helper function to generate array store
   413   void array_store(BasicType etype);
   414   // Helper function to compute array addressing
   415   Node* array_addressing(BasicType type, int vals, const Type* *result2=NULL);
   417   // Pass current map to exits
   418   void return_current(Node* value);
   420   // Register finalizers on return from Object.<init>
   421   void call_register_finalizer();
   423   // Insert a compiler safepoint into the graph
   424   void add_safepoint();
   426   // Insert a compiler safepoint into the graph, if there is a back-branch.
   427   void maybe_add_safepoint(int target_bci) {
   428     if (UseLoopSafepoints && target_bci <= bci()) {
   429       add_safepoint();
   430     }
   431   }
   433   // Note:  Intrinsic generation routines may be found in library_call.cpp.
   435   // Helper function to setup Ideal Call nodes
   436   void do_call();
   438   // Helper function to uncommon-trap or bailout for non-compilable call-sites
   439   bool can_not_compile_call_site(ciMethod *dest_method, ciInstanceKlass *klass);
   441   // Helper function to identify inlining potential at call-site
   442   ciMethod* optimize_inlining(ciMethod* caller, int bci, ciInstanceKlass* klass,
   443                               ciMethod *dest_method, const TypeOopPtr* receiver_type);
   445   // Helper function to setup for type-profile based inlining
   446   bool prepare_type_profile_inline(ciInstanceKlass* prof_klass, ciMethod* prof_method);
   448   // Helper functions for type checking bytecodes:
   449   void  do_checkcast();
   450   void  do_instanceof();
   452   // Helper functions for shifting & arithmetic
   453   void modf();
   454   void modd();
   455   void l2f();
   457   void do_irem();
   459   // implementation of _get* and _put* bytecodes
   460   void do_getstatic() { do_field_access(true,  false); }
   461   void do_getfield () { do_field_access(true,  true); }
   462   void do_putstatic() { do_field_access(false, false); }
   463   void do_putfield () { do_field_access(false, true); }
   465   // common code for making initial checks and forming addresses
   466   void do_field_access(bool is_get, bool is_field);
   467   bool static_field_ok_in_clinit(ciField *field, ciMethod *method);
   469   // common code for actually performing the load or store
   470   void do_get_xxx(const TypePtr* obj_type, Node* obj, ciField* field, bool is_field);
   471   void do_put_xxx(const TypePtr* obj_type, Node* obj, ciField* field, bool is_field);
   473   // loading from a constant field or the constant pool
   474   // returns false if push failed (non-perm field constants only, not ldcs)
   475   bool push_constant(ciConstant con, bool require_constant = false);
   477   // implementation of object creation bytecodes
   478   void do_new();
   479   void do_newarray(BasicType elemtype);
   480   void do_anewarray();
   481   void do_multianewarray();
   482   Node* expand_multianewarray(ciArrayKlass* array_klass, Node* *lengths, int ndimensions, int nargs);
   484   // implementation of jsr/ret
   485   void do_jsr();
   486   void do_ret();
   488   float   dynamic_branch_prediction(float &cnt);
   489   float   branch_prediction(float &cnt, BoolTest::mask btest, int target_bci);
   490   bool    seems_never_taken(float prob);
   492   void    do_ifnull(BoolTest::mask btest, Node* c);
   493   void    do_if(BoolTest::mask btest, Node* c);
   494   void    repush_if_args();
   495   void    adjust_map_after_if(BoolTest::mask btest, Node* c, float prob,
   496                               Block* path, Block* other_path);
   497   IfNode* jump_if_fork_int(Node* a, Node* b, BoolTest::mask mask);
   498   Node*   jump_if_join(Node* iffalse, Node* iftrue);
   499   void    jump_if_true_fork(IfNode *ifNode, int dest_bci_if_true, int prof_table_index);
   500   void    jump_if_false_fork(IfNode *ifNode, int dest_bci_if_false, int prof_table_index);
   501   void    jump_if_always_fork(int dest_bci_if_true, int prof_table_index);
   503   friend class SwitchRange;
   504   void    do_tableswitch();
   505   void    do_lookupswitch();
   506   void    jump_switch_ranges(Node* a, SwitchRange* lo, SwitchRange* hi, int depth = 0);
   507   bool    create_jump_tables(Node* a, SwitchRange* lo, SwitchRange* hi);
   509   // helper functions for methodData style profiling
   510   void test_counter_against_threshold(Node* cnt, int limit);
   511   void increment_and_test_invocation_counter(int limit);
   512   void test_for_osr_md_counter_at(ciMethodData* md, ciProfileData* data, ByteSize offset, int limit);
   513   Node* method_data_addressing(ciMethodData* md, ciProfileData* data, ByteSize offset, Node* idx = NULL, uint stride = 0);
   514   void increment_md_counter_at(ciMethodData* md, ciProfileData* data, ByteSize offset, Node* idx = NULL, uint stride = 0);
   515   void set_md_flag_at(ciMethodData* md, ciProfileData* data, int flag_constant);
   517   void profile_method_entry();
   518   void profile_taken_branch(int target_bci, bool force_update = false);
   519   void profile_not_taken_branch(bool force_update = false);
   520   void profile_call(Node* receiver);
   521   void profile_generic_call();
   522   void profile_receiver_type(Node* receiver);
   523   void profile_ret(int target_bci);
   524   void profile_null_checkcast();
   525   void profile_switch_case(int table_index);
   527   // helper function for call statistics
   528   void count_compiled_calls(bool at_method_entry, bool is_inline) PRODUCT_RETURN;
   530   Node_Notes* make_node_notes(Node_Notes* caller_nn);
   532   // Helper functions for handling normal and abnormal exits.
   533   void build_exits();
   535   // Fix up all exceptional control flow exiting a single bytecode.
   536   void do_exceptions();
   538   // Fix up all exiting control flow at the end of the parse.
   539   void do_exits();
   541   // Add Catch/CatchProjs
   542   // The call is either a Java call or the VM's rethrow stub
   543   void catch_call_exceptions(ciExceptionHandlerStream&);
   545   // Handle all exceptions thrown by the inlined method.
   546   // Also handles exceptions for individual bytecodes.
   547   void catch_inline_exceptions(SafePointNode* ex_map);
   549   // Bytecode classifier, helps decide to use uncommon_trap vs. rethrow_C.
   550   bool can_rerun_bytecode();
   552   // Merge the given map into correct exceptional exit state.
   553   // Assumes that there is no applicable local handler.
   554   void throw_to_exit(SafePointNode* ex_map);
   556  public:
   557 #ifndef PRODUCT
   558   // Handle PrintOpto, etc.
   559   void show_parse_info();
   560   void dump_map_adr_mem() const;
   561   static void print_statistics(); // Print some performance counters
   562   void dump();
   563   void dump_bci(int bci);
   564 #endif
   565 };

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