Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright 1998-2009 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.

  *

  */

 //** The DebugInformationRecorder collects debugging information

 //   for a compiled method.

 //   Debugging information is used for:

 //   - garbage collecting compiled frames

 //   - stack tracing across compiled frames

 //   - deoptimizating compiled frames

 //

 //   The implementation requires the compiler to use the recorder

 //   in the following order:

 //   1) Describe debug information for safepoints at increasing addresses.

 //      a) Add safepoint entry (use add_safepoint or add_non_safepoint)

 //      b) Describe scopes for that safepoint

 //         - create locals if needed (use create_scope_values)

 //         - create expressions if needed (use create_scope_values)

 //         - create monitor stack if needed (use create_monitor_values)

 //         - describe scope (use describe_scope)

 //         "repeat last four steps for all scopes"

 //         "outer most scope first and inner most scope last"

 //         NB: nodes from create_scope_values and create_locations

 //             can be reused for simple sharing.

 //         - mark the end of the scopes (end_safepoint or end_non_safepoint)

 //   2) Use oop_size, data_size, pcs_size to create the nmethod and

 //      finally migrate the debugging information into the nmethod

 //      by calling copy_to.

 class DebugToken; // Opaque datatype for stored:

                   //  - GrowableArray<ScopeValue*>

                   //  - GrowableArray<MonitorValue*>

 // Alias for InvocationEntryBci.

 // Both constants are used for a pseudo-BCI which refers

 // to the state just _before_ a method is entered.

 // SynchronizationEntryBCI is used where the emphasis

 // is on the implicit monitorenter of a synchronized method.

 const int SynchronizationEntryBCI = InvocationEntryBci;

 class DIR_Chunk; // private class, a nugget of collected information

 class DebugInformationRecorder: public ResourceObj {

  public:

   // constructor

   DebugInformationRecorder(OopRecorder* oop_recorder);

   // adds an oopmap at a specific offset

   void add_oopmap(int pc_offset, OopMap* map);

   // adds a jvm mapping at pc-offset, for a safepoint only

   void add_safepoint(int pc_offset, OopMap* map);

   // adds a jvm mapping at pc-offset, for a non-safepoint (profile point)

   void add_non_safepoint(int pc_offset);

   // Describes debugging information for a scope at the given pc_offset.

   // Calls must be in non-decreasing order of pc_offset.

   // If there are several calls at a single pc_offset,

   // then they occur in the same order as they were performed by the JVM,

   // with the most recent (innermost) call being described last.

   // For a safepoint, the pc_offset must have been mentioned

   // previously by add_safepoint.

   // Otherwise, the pc_offset must have been mentioned previously

   // by add_non_safepoint, and the locals, expressions, and monitors

   // must all be null.

   void describe_scope(int         pc_offset,

                       ciMethod*   method,

                       int         bci,

                       bool        reexecute,

                       bool        is_method_handle_invoke = false,

                       DebugToken* locals      = NULL,

                       DebugToken* expressions = NULL,

                       DebugToken* monitors    = NULL);

   void dump_object_pool(GrowableArray<ScopeValue*>* objects);

   // This call must follow every add_safepoint,

   // after any intervening describe_scope calls.

   void end_safepoint(int pc_offset)      { end_scopes(pc_offset, true); }

   void end_non_safepoint(int pc_offset)  { end_scopes(pc_offset, false); }

   // helper fuctions for describe_scope to enable sharing

   DebugToken* create_scope_values(GrowableArray<ScopeValue*>* values);

   DebugToken* create_monitor_values(GrowableArray<MonitorValue*>* monitors);

   // returns the size of the generated scopeDescs.

   int data_size();

   int pcs_size();

   int oop_size() { return oop_recorder()->oop_size(); }

   // copy the generated debugging information to nmethod

   void copy_to(nmethod* nm);

   // verifies the debug information

   void verify(const nmethod* code);

   static void print_statistics() PRODUCT_RETURN;

   // Method for setting oopmaps to temporarily preserve old handling of oopmaps

   OopMapSet *_oopmaps;

   void set_oopmaps(OopMapSet *oopmaps) { _oopmaps = oopmaps; }

   OopRecorder* oop_recorder() { return _oop_recorder; }

   int last_pc_offset() { return last_pc()->pc_offset(); }

   bool recording_non_safepoints() { return _recording_non_safepoints; }

  private:

   friend class ScopeDesc;

   friend class vframeStreamCommon;

   friend class DIR_Chunk;

   // True if we are recording non-safepoint scopes.

   // This flag is set if DebugNonSafepoints is true, or if

   // JVMTI post_compiled_method_load events are enabled.

   const bool _recording_non_safepoints;

   DebugInfoWriteStream* _stream;

   DebugInfoWriteStream* stream() const { return _stream; }

   OopRecorder* _oop_recorder;

   // Scopes that have been described so far.

   GrowableArray<DIR_Chunk*>* _all_chunks;

   GrowableArray<DIR_Chunk*>* _shared_chunks;

   DIR_Chunk* _next_chunk;

   DIR_Chunk* _next_chunk_limit;

 #ifdef ASSERT

   enum { rs_null, rs_safepoint, rs_non_safepoint };

   int _recording_state;

 #endif

   PcDesc* _pcs;

   int     _pcs_size;

   int     _pcs_length;

   // Note:  Would use GrowableArray<PcDesc>, but structs are not supported.

   // PC of most recent real safepoint before the current one,

   // updated after end_scopes.

   int _prev_safepoint_pc;

   PcDesc* last_pc() {

     guarantee(_pcs_length > 0, "a safepoint must be declared already");

     return &_pcs[_pcs_length-1];

   }

   PcDesc* prev_pc() {

     guarantee(_pcs_length > 1, "a safepoint must be declared already");

     return &_pcs[_pcs_length-2];

   }

   void add_new_pc_offset(int pc_offset);

   void end_scopes(int pc_offset, bool is_safepoint);

   int  serialize_monitor_values(GrowableArray<MonitorValue*>* monitors);

   int  serialize_scope_values(GrowableArray<ScopeValue*>* values);

   int  find_sharable_decode_offset(int stream_offset);

  public:

   enum { serialized_null = 0 };

 };