/*

 * Copyright (c) 1999, 2010, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

class MemoryBuffer;

class GraphBuilder VALUE_OBJ_CLASS_SPEC {

 private:

  // Per-scope data. These are pushed and popped as we descend into

  // inlined methods. Currently in order to generate good code in the

  // inliner we have to attempt to inline methods directly into the

  // basic block we are parsing; this adds complexity.

  class ScopeData: public CompilationResourceObj {

   private:

    ScopeData*  _parent;

    // bci-to-block mapping

    BlockList*   _bci2block;

    // Scope

    IRScope*     _scope;

    // Whether this scope or any parent scope has exception handlers

    bool         _has_handler;

    // The bytecodes

    ciBytecodeStream* _stream;

    // Work list

    BlockList*   _work_list;

    // Maximum inline size for this scope

    intx         _max_inline_size;

    // Expression stack depth at point where inline occurred

    int          _caller_stack_size;

    // The continuation point for the inline. Currently only used in

    // multi-block inlines, but eventually would like to use this for

    // all inlines for uniformity and simplicity; in this case would

    // get the continuation point from the BlockList instead of

    // fabricating it anew because Invokes would be considered to be

    // BlockEnds.

    BlockBegin*  _continuation;

    // Was this ScopeData created only for the parsing and inlining of

    // a jsr?

    bool         _parsing_jsr;

    // We track the destination bci of the jsr only to determine

    // bailout conditions, since we only handle a subset of all of the

    // possible jsr-ret control structures. Recursive invocations of a

    // jsr are disallowed by the verifier.

    int          _jsr_entry_bci;

    // We need to track the local variable in which the return address

    // was stored to ensure we can handle inlining the jsr, because we

    // don't handle arbitrary jsr/ret constructs.

    int          _jsr_ret_addr_local;

    // If we are parsing a jsr, the continuation point for rets

    BlockBegin*  _jsr_continuation;

    // Cloned XHandlers for jsr-related ScopeDatas

    XHandlers*   _jsr_xhandlers;

    // Number of returns seen in this scope

    int          _num_returns;

    // In order to generate profitable code for inlining, we currently

    // have to perform an optimization for single-block inlined

    // methods where we continue parsing into the same block. This

    // allows us to perform CSE across inlined scopes and to avoid

    // storing parameters to the stack. Having a global register

    // allocator and being able to perform global CSE would allow this

    // code to be removed and thereby simplify the inliner.

    BlockBegin*  _cleanup_block;       // The block to which the return was added

    Instruction* _cleanup_return_prev; // Instruction before return instruction

    ValueStack*  _cleanup_state;       // State of that block (not yet pinned)

   public:

    ScopeData(ScopeData* parent);

    ScopeData* parent() const                      { return _parent;            }

    BlockList* bci2block() const                   { return _bci2block;         }

    void       set_bci2block(BlockList* bci2block) { _bci2block = bci2block;    }

    // NOTE: this has a different effect when parsing jsrs

    BlockBegin* block_at(int bci);

    IRScope* scope() const                         { return _scope;             }

    // Has side-effect of setting has_handler flag

    void set_scope(IRScope* scope);

    // Whether this or any parent scope has exception handlers

    bool has_handler() const                       { return _has_handler;       }

    void set_has_handler()                         { _has_handler = true;       }

    // Exception handlers list to be used for this scope

    XHandlers* xhandlers() const;

    // How to get a block to be parsed

    void add_to_work_list(BlockBegin* block);

    // How to remove the next block to be parsed; returns NULL if none left

    BlockBegin* remove_from_work_list();

    // Indicates parse is over

    bool is_work_list_empty() const;

    ciBytecodeStream* stream()                     { return _stream;            }

    void set_stream(ciBytecodeStream* stream)      { _stream = stream;          }

    intx max_inline_size() const                   { return _max_inline_size;   }

    BlockBegin* continuation() const               { return _continuation;      }

    void set_continuation(BlockBegin* cont)        { _continuation = cont;      }

    // Indicates whether this ScopeData was pushed only for the

    // parsing and inlining of a jsr

    bool parsing_jsr() const                       { return _parsing_jsr;       }

    void set_parsing_jsr()                         { _parsing_jsr = true;       }

    int  jsr_entry_bci() const                     { return _jsr_entry_bci;     }

    void set_jsr_entry_bci(int bci)                { _jsr_entry_bci = bci;      }

    void set_jsr_return_address_local(int local_no){ _jsr_ret_addr_local = local_no; }

    int  jsr_return_address_local() const          { return _jsr_ret_addr_local; }

    // Must be called after scope is set up for jsr ScopeData

    void setup_jsr_xhandlers();

    // The jsr continuation is only used when parsing_jsr is true, and

    // is different from the "normal" continuation since we can end up

    // doing a return (rather than a ret) from within a subroutine

    BlockBegin* jsr_continuation() const           { return _jsr_continuation;  }

    void set_jsr_continuation(BlockBegin* cont)    { _jsr_continuation = cont;  }

    int num_returns();

    void incr_num_returns();

    void set_inline_cleanup_info(BlockBegin* block,

                                 Instruction* return_prev,

                                 ValueStack* return_state);

    BlockBegin*  inline_cleanup_block() const      { return _cleanup_block; }

    Instruction* inline_cleanup_return_prev() const{ return _cleanup_return_prev; }

    ValueStack*  inline_cleanup_state() const      { return _cleanup_state; }

  };

  // for all GraphBuilders

  static bool       _can_trap[Bytecodes::number_of_java_codes];

  // for each instance of GraphBuilder

  ScopeData*        _scope_data;                 // Per-scope data; used for inlining

  Compilation*      _compilation;                // the current compilation

  ValueMap*         _vmap;                       // the map of values encountered (for CSE)

  MemoryBuffer*     _memory;

  const char*       _inline_bailout_msg;         // non-null if most recent inline attempt failed

  int               _instruction_count;          // for bailing out in pathological jsr/ret cases

  BlockBegin*       _start;                      // the start block

  BlockBegin*       _osr_entry;                  // the osr entry block block

  ValueStack*       _initial_state;              // The state for the start block

  // for each call to connect_to_end; can also be set by inliner

  BlockBegin*       _block;                      // the current block

  ValueStack*       _state;                      // the current execution state

  Instruction*      _last;                       // the last instruction added

  bool              _skip_block;                 // skip processing of the rest of this block

  // accessors

  ScopeData*        scope_data() const           { return _scope_data; }

  Compilation*      compilation() const          { return _compilation; }

  BlockList*        bci2block() const            { return scope_data()->bci2block(); }

  ValueMap*         vmap() const                 { assert(UseLocalValueNumbering, "should not access otherwise"); return _vmap; }

  bool              has_handler() const          { return scope_data()->has_handler(); }

  BlockBegin*       block() const                { return _block; }

  ValueStack*       state() const                { return _state; }

  void              set_state(ValueStack* state) { _state = state; }

  IRScope*          scope() const                { return scope_data()->scope(); }

  ciMethod*         method() const               { return scope()->method(); }

  ciBytecodeStream* stream() const               { return scope_data()->stream(); }

  Instruction*      last() const                 { return _last; }

  Bytecodes::Code   code() const                 { return stream()->cur_bc(); }

  int               bci() const                  { return stream()->cur_bci(); }

  int               next_bci() const             { return stream()->next_bci(); }

  // unified bailout support

  void bailout(const char* msg) const            { compilation()->bailout(msg); }

  bool bailed_out() const                        { return compilation()->bailed_out(); }

  // stack manipulation helpers

  void ipush(Value t) const                      { state()->ipush(t); }

  void lpush(Value t) const                      { state()->lpush(t); }

  void fpush(Value t) const                      { state()->fpush(t); }

  void dpush(Value t) const                      { state()->dpush(t); }

  void apush(Value t) const                      { state()->apush(t); }

  void  push(ValueType* type, Value t) const     { state()-> push(type, t); }

  Value ipop()                                   { return state()->ipop(); }

  Value lpop()                                   { return state()->lpop(); }

  Value fpop()                                   { return state()->fpop(); }

  Value dpop()                                   { return state()->dpop(); }

  Value apop()                                   { return state()->apop(); }

  Value  pop(ValueType* type)                    { return state()-> pop(type); }

  // instruction helpers

  void load_constant();

  void load_local(ValueType* type, int index);

  void store_local(ValueType* type, int index);

  void store_local(ValueStack* state, Value value, ValueType* type, int index);

  void load_indexed (BasicType type);

  void store_indexed(BasicType type);

  void stack_op(Bytecodes::Code code);

  void negate_op(ValueType* type);

  void shift_op(ValueType* type, Bytecodes::Code code);

  void logic_op(ValueType* type, Bytecodes::Code code);

  void compare_op(ValueType* type, Bytecodes::Code code);

  void convert(Bytecodes::Code op, BasicType from, BasicType to);

  void increment();

  void _goto(int from_bci, int to_bci);

  void if_node(Value x, If::Condition cond, Value y, ValueStack* stack_before);

  void if_zero(ValueType* type, If::Condition cond);

  void if_null(ValueType* type, If::Condition cond);

  void if_same(ValueType* type, If::Condition cond);

  void jsr(int dest);

  void ret(int local_index);

  void table_switch();

  void lookup_switch();

  void method_return(Value x);

  void call_register_finalizer();

  void access_field(Bytecodes::Code code);

  void invoke(Bytecodes::Code code);

  void new_instance(int klass_index);

  void new_type_array();

  void new_object_array();

  void check_cast(int klass_index);

  void instance_of(int klass_index);

  void monitorenter(Value x, int bci);

  void monitorexit(Value x, int bci);

  void new_multi_array(int dimensions);

  void throw_op(int bci);

  Value round_fp(Value fp_value);

  // stack/code manipulation helpers

  Instruction* append_with_bci(Instruction* instr, int bci);

  Instruction* append(Instruction* instr);

  Instruction* append_split(StateSplit* instr);

  // other helpers

  BlockBegin* block_at(int bci)                  { return scope_data()->block_at(bci); }

  void connect_to_end(BlockBegin* beg);

  void null_check(Value value);

  void eliminate_redundant_phis(BlockBegin* start);

  BlockEnd* iterate_bytecodes_for_block(int bci);

  void iterate_all_blocks(bool start_in_current_block_for_inlining = false);

  Dependencies* dependency_recorder() const; // = compilation()->dependencies()

  bool direct_compare(ciKlass* k);

  void kill_all();

  //

  // Inlining support

  //

  // accessors

  bool parsing_jsr() const                               { return scope_data()->parsing_jsr();           }

  BlockBegin* continuation() const                       { return scope_data()->continuation();          }

  BlockBegin* jsr_continuation() const                   { return scope_data()->jsr_continuation();      }

  void set_continuation(BlockBegin* continuation)        { scope_data()->set_continuation(continuation); }

  void set_inline_cleanup_info(BlockBegin* block,

                               Instruction* return_prev,

                               ValueStack* return_state) { scope_data()->set_inline_cleanup_info(block,

                                                                                                  return_prev,

                                                                                                  return_state); }

  BlockBegin*  inline_cleanup_block() const              { return scope_data()->inline_cleanup_block();  }

  Instruction* inline_cleanup_return_prev() const        { return scope_data()->inline_cleanup_return_prev(); }

  ValueStack*  inline_cleanup_state() const              { return scope_data()->inline_cleanup_state();  }

  void incr_num_returns()                                { scope_data()->incr_num_returns();             }

  int  num_returns() const                               { return scope_data()->num_returns();           }

  intx max_inline_size() const                           { return scope_data()->max_inline_size();       }

  int  inline_level() const                              { return scope()->level();                      }

  int  recursive_inline_level(ciMethod* callee) const;

  // inlining of synchronized methods

  void inline_sync_entry(Value lock, BlockBegin* sync_handler);

  void fill_sync_handler(Value lock, BlockBegin* sync_handler, bool default_handler = false);

  // inliners

  bool try_inline(ciMethod* callee, bool holder_known);

  bool try_inline_intrinsics(ciMethod* callee);

  bool try_inline_full      (ciMethod* callee, bool holder_known);

  bool try_inline_jsr(int jsr_dest_bci);

  // helpers

  void inline_bailout(const char* msg);

  BlockBegin* header_block(BlockBegin* entry, BlockBegin::Flag f, ValueStack* state);

  BlockBegin* setup_start_block(int osr_bci, BlockBegin* std_entry, BlockBegin* osr_entry, ValueStack* init_state);

  void setup_osr_entry_block();

  void clear_inline_bailout();

  ValueStack* state_at_entry();

  void push_root_scope(IRScope* scope, BlockList* bci2block, BlockBegin* start);

  void push_scope(ciMethod* callee, BlockBegin* continuation);

  void push_scope_for_jsr(BlockBegin* jsr_continuation, int jsr_dest_bci);

  void pop_scope();

  void pop_scope_for_jsr();

  bool append_unsafe_get_obj(ciMethod* callee, BasicType t, bool is_volatile);

  bool append_unsafe_put_obj(ciMethod* callee, BasicType t, bool is_volatile);

  bool append_unsafe_get_raw(ciMethod* callee, BasicType t);

  bool append_unsafe_put_raw(ciMethod* callee, BasicType t);

  bool append_unsafe_prefetch(ciMethod* callee, bool is_store, bool is_static);

  void append_unsafe_CAS(ciMethod* callee);

  NOT_PRODUCT(void print_inline_result(ciMethod* callee, bool res);)

  void profile_call(Value recv, ciKlass* predicted_holder);

  void profile_invocation(ciMethod* inlinee, ValueStack* state, int bci);

  // Shortcuts to profiling control.

  bool is_profiling()          { return _compilation->is_profiling();          }

  bool count_invocations()     { return _compilation->count_invocations();     }

  bool count_backedges()       { return _compilation->count_backedges();       }

  bool profile_branches()      { return _compilation->profile_branches();      }

  bool profile_calls()         { return _compilation->profile_calls();         }

  bool profile_inlined_calls() { return _compilation->profile_inlined_calls(); }

  bool profile_checkcasts()    { return _compilation->profile_checkcasts();    }

 public:

  NOT_PRODUCT(void print_stats();)

  // initialization

  static void initialize();

  // public

  static bool can_trap(ciMethod* method, Bytecodes::Code code) {

    assert(0 <= code && code < Bytecodes::number_of_java_codes, "illegal bytecode");

    if (_can_trap[code]) return true;

    // special handling for finalizer registration

    return code == Bytecodes::_return && method->intrinsic_id() == vmIntrinsics::_Object_init;

  }

  // creation

  GraphBuilder(Compilation* compilation, IRScope* scope);

  static void sort_top_into_worklist(BlockList* worklist, BlockBegin* top);

  BlockBegin* start() const                      { return _start; }

};