1 /*
   2  * Copyright (c) 1997, 2015, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_CODE_DEBUGINFO_HPP
  26 #define SHARE_VM_CODE_DEBUGINFO_HPP
  27 
  28 #include "code/compressedStream.hpp"
  29 #include "code/location.hpp"
  30 #include "code/nmethod.hpp"
  31 #include "code/oopRecorder.hpp"
  32 #include "runtime/stackValue.hpp"
  33 #include "utilities/growableArray.hpp"
  34 
  35 // Classes used for serializing debugging information.
  36 // These abstractions are introducted to provide symmetric
  37 // read and write operations.
  38 
  39 // ScopeValue        describes the value of a variable/expression in a scope
  40 // - LocationValue   describes a value in a given location (in frame or register)
  41 // - ConstantValue   describes a constant
  42 
  43 class ConstantOopReadValue;
  44 class ObjectValue;
  45 
  46 class ScopeValue: public ResourceObj {
  47  public:
  48   // Testers
  49   virtual bool is_location() const { return false; }
  50   virtual bool is_object() const { return false; }
  51   virtual bool is_constant_int() const { return false; }
  52   virtual bool is_constant_double() const { return false; }
  53   virtual bool is_constant_long() const { return false; }
  54   virtual bool is_constant_oop() const { return false; }
  55   virtual bool equals(ScopeValue* other) const { return false; }
  56 
  57   ConstantOopReadValue* as_ConstantOopReadValue() {
  58     assert(is_constant_oop(), "must be");
  59     return (ConstantOopReadValue*) this;
  60   }
  61 
  62   ObjectValue* as_ObjectValue() {
  63     assert(is_object(), "must be");
  64     return (ObjectValue*)this;
  65   }
  66 
  67   // Serialization of debugging information
  68   virtual void write_on(DebugInfoWriteStream* stream) = 0;
  69   static ScopeValue* read_from(DebugInfoReadStream* stream);
  70 };
  71 
  72 
  73 // A Location value describes a value in a given location; i.e. the corresponding
  74 // logical entity (e.g., a method temporary) lives in this location.
  75 
  76 class LocationValue: public ScopeValue {
  77  private:
  78   Location  _location;
  79  public:
  80   LocationValue(Location location)           { _location = location; }
  81   bool      is_location() const              { return true; }
  82   Location  location() const                 { return _location; }
  83 
  84   // Serialization of debugging information
  85   LocationValue(DebugInfoReadStream* stream);
  86   void write_on(DebugInfoWriteStream* stream);
  87 
  88   // Printing
  89   void print_on(outputStream* st) const;
  90 };
  91 
  92 
  93 // An ObjectValue describes an object eliminated by escape analysis.
  94 
  95 class ObjectValue: public ScopeValue {
  96  private:
  97   int                        _id;
  98   ScopeValue*                _klass;
  99   GrowableArray<ScopeValue*> _field_values;
 100   Handle                     _value;
 101   bool                       _visited;
 102 
 103  public:
 104   ObjectValue(int id, ScopeValue* klass)
 105      : _id(id)
 106      , _klass(klass)
 107      , _field_values()
 108      , _value()
 109      , _visited(false) {
 110     assert(klass->is_constant_oop(), "should be constant java mirror oop");
 111   }
 112 
 113   ObjectValue(int id)
 114      : _id(id)
 115      , _klass(NULL)
 116      , _field_values()
 117      , _value()
 118      , _visited(false) {}
 119 
 120   // Accessors
 121   bool                        is_object() const         { return true; }
 122   int                         id() const                { return _id; }
 123   ScopeValue*                 klass() const             { return _klass; }
 124   GrowableArray<ScopeValue*>* field_values()            { return &_field_values; }
 125   ScopeValue*                 field_at(int i) const     { return _field_values.at(i); }
 126   int                         field_size()              { return _field_values.length(); }
 127   Handle                      value() const             { return _value; }
 128   bool                        is_visited() const        { return _visited; }
 129 
 130   void                        set_value(oop value)      { _value = Handle(value); }
 131   void                        set_visited(bool visited) { _visited = false; }
 132 
 133   // Serialization of debugging information
 134   void read_object(DebugInfoReadStream* stream);
 135   void write_on(DebugInfoWriteStream* stream);
 136 
 137   // Printing
 138   void print_on(outputStream* st) const;
 139   void print_fields_on(outputStream* st) const;
 140 };
 141 
 142 
 143 // A ConstantIntValue describes a constant int; i.e., the corresponding logical entity
 144 // is either a source constant or its computation has been constant-folded.
 145 
 146 class ConstantIntValue: public ScopeValue {
 147  private:
 148   jint _value;
 149  public:
 150   ConstantIntValue(jint value)         { _value = value; }
 151   jint value() const                   { return _value;  }
 152   bool is_constant_int() const         { return true;    }
 153   bool equals(ScopeValue* other) const { return false;   }
 154 
 155   // Serialization of debugging information
 156   ConstantIntValue(DebugInfoReadStream* stream);
 157   void write_on(DebugInfoWriteStream* stream);
 158 
 159   // Printing
 160   void print_on(outputStream* st) const;
 161 };
 162 
 163 class ConstantLongValue: public ScopeValue {
 164  private:
 165   jlong _value;
 166  public:
 167   ConstantLongValue(jlong value)       { _value = value; }
 168   jlong value() const                  { return _value;  }
 169   bool is_constant_long() const        { return true;    }
 170   bool equals(ScopeValue* other) const { return false;   }
 171 
 172   // Serialization of debugging information
 173   ConstantLongValue(DebugInfoReadStream* stream);
 174   void write_on(DebugInfoWriteStream* stream);
 175 
 176   // Printing
 177   void print_on(outputStream* st) const;
 178 };
 179 
 180 class ConstantDoubleValue: public ScopeValue {
 181  private:
 182   jdouble _value;
 183  public:
 184   ConstantDoubleValue(jdouble value)   { _value = value; }
 185   jdouble value() const                { return _value;  }
 186   bool is_constant_double() const      { return true;    }
 187   bool equals(ScopeValue* other) const { return false;   }
 188 
 189   // Serialization of debugging information
 190   ConstantDoubleValue(DebugInfoReadStream* stream);
 191   void write_on(DebugInfoWriteStream* stream);
 192 
 193   // Printing
 194   void print_on(outputStream* st) const;
 195 };
 196 
 197 // A ConstantOopWriteValue is created by the compiler to
 198 // be written as debugging information.
 199 
 200 class ConstantOopWriteValue: public ScopeValue {
 201  private:
 202   jobject _value;
 203  public:
 204   ConstantOopWriteValue(jobject value) { _value = value; }
 205   jobject value() const                { return _value;  }
 206   bool is_constant_oop() const         { return true;    }
 207   bool equals(ScopeValue* other) const { return false;   }
 208 
 209   // Serialization of debugging information
 210   void write_on(DebugInfoWriteStream* stream);
 211 
 212   // Printing
 213   void print_on(outputStream* st) const;
 214 };
 215 
 216 // A ConstantOopReadValue is created by the VM when reading
 217 // debug information
 218 
 219 class ConstantOopReadValue: public ScopeValue {
 220  private:
 221   Handle _value;
 222  public:
 223   Handle value() const                 { return _value;  }
 224   bool is_constant_oop() const         { return true;    }
 225   bool equals(ScopeValue* other) const { return false;   }
 226 
 227   // Serialization of debugging information
 228   ConstantOopReadValue(DebugInfoReadStream* stream);
 229   void write_on(DebugInfoWriteStream* stream);
 230 
 231   // Printing
 232   void print_on(outputStream* st) const;
 233 };
 234 
 235 // MonitorValue describes the pair used for monitor_enter and monitor_exit.
 236 
 237 class MonitorValue: public ResourceObj {
 238  private:
 239   ScopeValue* _owner;
 240   Location    _basic_lock;
 241   bool        _eliminated;
 242  public:
 243   // Constructor
 244   MonitorValue(ScopeValue* owner, Location basic_lock, bool eliminated = false);
 245 
 246   // Accessors
 247   ScopeValue*  owner()      const { return _owner; }
 248   Location     basic_lock() const { return _basic_lock;  }
 249   bool         eliminated() const { return _eliminated; }
 250 
 251   // Serialization of debugging information
 252   MonitorValue(DebugInfoReadStream* stream);
 253   void write_on(DebugInfoWriteStream* stream);
 254 
 255   // Printing
 256   void print_on(outputStream* st) const;
 257 };
 258 
 259 // DebugInfoReadStream specializes CompressedReadStream for reading
 260 // debugging information. Used by ScopeDesc.
 261 
 262 class DebugInfoReadStream : public CompressedReadStream {
 263  private:
 264   const nmethod* _code;
 265   const nmethod* code() const { return _code; }
 266   GrowableArray<ScopeValue*>* _obj_pool;
 267  public:
 268   DebugInfoReadStream(const nmethod* code, int offset, GrowableArray<ScopeValue*>* obj_pool = NULL) :
 269     CompressedReadStream(code->scopes_data_begin(), offset) {
 270     _code = code;
 271     _obj_pool = obj_pool;
 272 
 273   } ;
 274 
 275   oop read_oop();
 276   Method* read_method() {
 277     Method* o = (Method*)(code()->metadata_at(read_int()));
 278     // is_metadata() is a faster check than is_metaspace_object()
 279     assert(o == NULL || o->is_metadata(), "meta data only");
 280     return o;
 281   }
 282   ScopeValue* read_object_value();
 283   ScopeValue* get_cached_object();
 284   // BCI encoding is mostly unsigned, but -1 is a distinguished value
 285   int read_bci() { return read_int() + InvocationEntryBci; }
 286 };
 287 
 288 // DebugInfoWriteStream specializes CompressedWriteStream for
 289 // writing debugging information. Used by ScopeDescRecorder.
 290 
 291 class DebugInfoWriteStream : public CompressedWriteStream {
 292  private:
 293   DebugInformationRecorder* _recorder;
 294   DebugInformationRecorder* recorder() const { return _recorder; }
 295  public:
 296   DebugInfoWriteStream(DebugInformationRecorder* recorder, int initial_size);
 297   void write_handle(jobject h);
 298   void write_bci(int bci) { write_int(bci - InvocationEntryBci); }
 299 
 300   void write_metadata(Metadata* m);
 301 };
 302 
 303 #endif // SHARE_VM_CODE_DEBUGINFO_HPP