/*

 * 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 ciMethodBlocks;

class MethodLiveness;

class BitMap;

class Arena;

class BCEscapeAnalyzer;

// ciMethod

//

// This class represents a methodOop in the HotSpot virtual

// machine.

class ciMethod : public ciObject {

  friend class CompileBroker;

  CI_PACKAGE_ACCESS

  friend class ciEnv;

  friend class ciExceptionHandlerStream;

  friend class ciBytecodeStream;

  friend class ciMethodHandle;

 private:

  // General method information.

  ciFlags          _flags;

  ciSymbol*        _name;

  ciInstanceKlass* _holder;

  ciSignature*     _signature;

  ciMethodData*    _method_data;

  ciMethodBlocks*   _method_blocks;

  // Code attributes.

  int _code_size;

  int _max_stack;

  int _max_locals;

  vmIntrinsics::ID _intrinsic_id;

  int _handler_count;

  int _interpreter_invocation_count;

  int _interpreter_throwout_count;

  bool _uses_monitors;

  bool _balanced_monitors;

  bool _can_be_statically_bound;

  // Lazy fields, filled in on demand

  address              _code;

  ciExceptionHandler** _exception_handlers;

  // Optional liveness analyzer.

  MethodLiveness* _liveness;

#if defined(COMPILER2) || defined(SHARK)

  ciTypeFlow*         _flow;

  BCEscapeAnalyzer*   _bcea;

#endif

  ciMethod(methodHandle h_m);

  ciMethod(ciInstanceKlass* holder, ciSymbol* name, ciSymbol* signature);

  methodOop get_methodOop() const {

    methodOop m = (methodOop)get_oop();

    assert(m != NULL, "illegal use of unloaded method");

    return m;

  }

  oop loader() const                             { return _holder->loader(); }

  const char* type_string()                      { return "ciMethod"; }

  void print_impl(outputStream* st);

  void load_code();

  void check_is_loaded() const                   { assert(is_loaded(), "not loaded"); }

  void build_method_data(methodHandle h_m);

  void code_at_put(int bci, Bytecodes::Code code) {

    Bytecodes::check(code);

    assert(0 <= bci && bci < code_size(), "valid bci");

    address bcp = _code + bci;

    *bcp = code;

  }

 public:

  // Basic method information.

  ciFlags flags() const                          { check_is_loaded(); return _flags; }

  ciSymbol* name() const                         { return _name; }

  ciInstanceKlass* holder() const                { return _holder; }

  ciMethodData* method_data();

  // Signature information.

  ciSignature* signature() const                 { return _signature; }

  ciType*      return_type() const               { return _signature->return_type(); }

  int          arg_size_no_receiver() const      { return _signature->size(); }

  int          arg_size() const                  { return _signature->size() + (_flags.is_static() ? 0 : 1); }

  // Method code and related information.

  address code()                                 { if (_code == NULL) load_code(); return _code; }

  int code_size() const                          { check_is_loaded(); return _code_size; }

  int max_stack() const                          { check_is_loaded(); return _max_stack; }

  int max_locals() const                         { check_is_loaded(); return _max_locals; }

  vmIntrinsics::ID intrinsic_id() const          { check_is_loaded(); return _intrinsic_id; }

  bool has_exception_handlers() const            { check_is_loaded(); return _handler_count > 0; }

  int exception_table_length() const             { check_is_loaded(); return _handler_count; }

  int interpreter_invocation_count() const       { check_is_loaded(); return _interpreter_invocation_count; }

  int interpreter_throwout_count() const         { check_is_loaded(); return _interpreter_throwout_count; }

  Bytecodes::Code java_code_at_bci(int bci) {

    address bcp = code() + bci;

    return Bytecodes::java_code_at(bcp);

  }

  BCEscapeAnalyzer  *get_bcea();

  ciMethodBlocks    *get_method_blocks();

  bool    has_linenumber_table() const;          // length unknown until decompression

  u_char* compressed_linenumber_table() const;   // not preserved by gc

  int line_number_from_bci(int bci) const;

  // Runtime information.

  int           vtable_index();

#ifdef SHARK

  int           itable_index();

#endif // SHARK

  address       native_entry();

  address       interpreter_entry();

  // Analysis and profiling.

  //

  // Usage note: liveness_at_bci and init_vars should be wrapped in ResourceMarks.

  bool          uses_monitors() const            { return _uses_monitors; } // this one should go away, it has a misleading name

  bool          has_monitor_bytecodes() const    { return _uses_monitors; }

  bool          has_balanced_monitors();

  // Returns a bitmap indicating which locals are required to be

  // maintained as live for deopt.  raw_liveness_at_bci is always the

  // direct output of the liveness computation while liveness_at_bci

  // may mark all locals as live to improve support for debugging Java

  // code by maintaining the state of as many locals as possible.

  MethodLivenessResult raw_liveness_at_bci(int bci);

  MethodLivenessResult liveness_at_bci(int bci);

  // Get the interpreters viewpoint on oop liveness.  MethodLiveness is

  // conservative in the sense that it may consider locals to be live which

  // cannot be live, like in the case where a local could contain an oop or

  // a primitive along different paths.  In that case the local must be

  // dead when those paths merge. Since the interpreter's viewpoint is

  // used when gc'ing an interpreter frame we need to use its viewpoint

  // during OSR when loading the locals.

  BitMap  live_local_oops_at_bci(int bci);

#ifdef COMPILER1

  const BitMap  bci_block_start();

#endif

  ciTypeFlow*   get_flow_analysis();

  ciTypeFlow*   get_osr_flow_analysis(int osr_bci);  // alternate entry point

  ciCallProfile call_profile_at_bci(int bci);

  int           interpreter_call_site_count(int bci);

  // Given a certain calling environment, find the monomorphic target

  // for the call.  Return NULL if the call is not monomorphic in

  // its calling environment.

  ciMethod* find_monomorphic_target(ciInstanceKlass* caller,

                                    ciInstanceKlass* callee_holder,

                                    ciInstanceKlass* actual_receiver);

  // Given a known receiver klass, find the target for the call.

  // Return NULL if the call has no target or is abstract.

  ciMethod* resolve_invoke(ciKlass* caller, ciKlass* exact_receiver);

  // Find the proper vtable index to invoke this method.

  int resolve_vtable_index(ciKlass* caller, ciKlass* receiver);

  // Compilation directives

  bool will_link(ciKlass* accessing_klass,

                 ciKlass* declared_method_holder,

                 Bytecodes::Code bc);

  bool should_exclude();

  bool should_inline();

  bool should_not_inline();

  bool should_print_assembly();

  bool break_at_execute();

  bool has_option(const char *option);

  bool can_be_compiled();

  bool can_be_osr_compiled(int entry_bci);

  void set_not_compilable();

  bool has_compiled_code();

  void log_nmethod_identity(xmlStream* log);

  bool is_not_reached(int bci);

  bool was_executed_more_than(int times);

  bool has_unloaded_classes_in_signature();

  bool is_klass_loaded(int refinfo_index, bool must_be_resolved) const;

  bool check_call(int refinfo_index, bool is_static) const;

  void build_method_data();  // make sure it exists in the VM also

  int scale_count(int count, float prof_factor = 1.);  // make MDO count commensurate with IIC

  // JSR 292 support

  bool is_method_handle_invoke()  const;

  bool is_method_handle_adapter() const;

  ciInstance* method_handle_type();

  // What kind of ciObject is this?

  bool is_method()                               { return true; }

  // Java access flags

  bool is_public      () const                   { return flags().is_public(); }

  bool is_private     () const                   { return flags().is_private(); }

  bool is_protected   () const                   { return flags().is_protected(); }

  bool is_static      () const                   { return flags().is_static(); }

  bool is_final       () const                   { return flags().is_final(); }

  bool is_synchronized() const                   { return flags().is_synchronized(); }

  bool is_native      () const                   { return flags().is_native(); }

  bool is_interface   () const                   { return flags().is_interface(); }

  bool is_abstract    () const                   { return flags().is_abstract(); }

  bool is_strict      () const                   { return flags().is_strict(); }

  // Other flags

  bool is_empty_method() const;

  bool is_vanilla_constructor() const;

  bool is_final_method() const                   { return is_final() || holder()->is_final(); }

  bool has_loops      () const;

  bool has_jsrs       () const;

  bool is_accessor    () const;

  bool is_initializer () const;

  bool can_be_statically_bound() const           { return _can_be_statically_bound; }

  // Print the bytecodes of this method.

  void print_codes_on(outputStream* st);

  void print_codes() {

    print_codes_on(tty);

  }

  void print_codes_on(int from, int to, outputStream* st);

  // Print the name of this method in various incarnations.

  void print_name(outputStream* st = tty);

  void print_short_name(outputStream* st = tty);

  methodOop get_method_handle_target() {

    klassOop receiver_limit_oop = NULL;

    int flags = 0;

    return MethodHandles::decode_method(get_oop(), receiver_limit_oop, flags);

  }

};