1 /*
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  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
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 24 
 25 #ifndef SHARE_CODE_SCOPEDESC_HPP
 26 #define SHARE_CODE_SCOPEDESC_HPP
 27 
 28 #include "code/debugInfo.hpp"
 29 #include "code/pcDesc.hpp"
 30 #include "oops/method.hpp"
 31 #include "utilities/growableArray.hpp"
 32 
 33 // SimpleScopeDesc is used when all you need to extract from
 34 // a given pc,nmethod pair is a Method* and a bci. This is
 35 // quite a bit faster than allocating a full ScopeDesc, but
 36 // very limited in abilities.
 37 
 38 class SimpleScopeDesc : public StackObj {
 39  private:
 40   Method* _method;
 41   int _bci;
 42   bool _is_optimized_linkToNative;
 43 
 44  public:
 45   SimpleScopeDesc(CompiledMethod* code, address pc) {
 46     PcDesc* pc_desc = code->pc_desc_at(pc);
 47     assert(pc_desc != NULL, "Must be able to find matching PcDesc");
 48     // save this here so we only have to look up the PcDesc once
 49     _is_optimized_linkToNative = pc_desc->is_optimized_linkToNative();
 50     DebugInfoReadStream buffer(code, pc_desc->scope_decode_offset());
 51     int ignore_sender = buffer.read_int();
 52     _method           = buffer.read_method();
 53     _bci              = buffer.read_bci();
 54   }
 55 
 56   Method* method() { return _method; }
 57   int bci() { return _bci; }
 58   bool is_optimized_linkToNative() { return _is_optimized_linkToNative; }
 59 };
 60 
 61 // ScopeDescs contain the information that makes source-level debugging of
 62 // nmethods possible; each scopeDesc describes a method activation
 63 
 64 class ScopeDesc : public ResourceObj {
 65  public:
 66   // Constructor
 67   ScopeDesc(const CompiledMethod* code, PcDesc* pd, bool ignore_objects = false);
 68 
 69   // Direct access to scope
 70   ScopeDesc* at_offset(int decode_offset) { return new ScopeDesc(this, decode_offset); }
 71 
 72   // JVM state
 73   Method* method()      const { return _method; }
 74   int          bci()      const { return _bci;    }
 75   bool should_reexecute() const { return _reexecute; }
 76   bool rethrow_exception() const { return _rethrow_exception; }
 77   bool return_oop()       const { return _return_oop; }
 78   // Returns true if one or more NoEscape or ArgEscape objects exist in
 79   // any of the scopes at compiled pc.
 80   bool has_ea_local_in_scope() const { return _has_ea_local_in_scope; }
 81   bool arg_escape()       const { return _arg_escape; }
 82 
 83   GrowableArray<ScopeValue*>*   locals();
 84   GrowableArray<ScopeValue*>*   expressions();
 85   GrowableArray<MonitorValue*>* monitors();
 86   GrowableArray<ScopeValue*>*   objects();
 87 
 88   // Stack walking, returns NULL if this is the outer most scope.
 89   ScopeDesc* sender() const;
 90 
 91   // Returns where the scope was decoded
 92   int decode_offset() const { return _decode_offset; }
 93 
 94   int sender_decode_offset() const { return _sender_decode_offset; }
 95 
 96   // Tells whether sender() returns NULL
 97   bool is_top() const;
 98 
 99  private:
100   void initialize(const ScopeDesc* parent, int decode_offset);
101   // Alternative constructors
102   ScopeDesc(const ScopeDesc* parent);
103   ScopeDesc(const ScopeDesc* parent, int decode_offset);
104 
105   // JVM state
106   Method*       _method;
107   int           _bci;
108   bool          _reexecute;
109   bool          _rethrow_exception;
110   bool          _return_oop;
111   bool          _has_ea_local_in_scope;       // One or more NoEscape or ArgEscape objects exist in
112                                               // any of the scopes at compiled pc.
113   bool          _arg_escape;                  // Compiled Java call in youngest scope passes ArgEscape
114 
115   // Decoding offsets
116   int _decode_offset;
117   int _sender_decode_offset;
118   int _locals_decode_offset;
119   int _expressions_decode_offset;
120   int _monitors_decode_offset;
121 
122   // Object pool
123   GrowableArray<ScopeValue*>* _objects;
124 
125   // Nmethod information
126   const CompiledMethod* _code;
127 
128   // Decoding operations
129   void decode_body();
130   GrowableArray<ScopeValue*>* decode_scope_values(int decode_offset);
131   GrowableArray<MonitorValue*>* decode_monitor_values(int decode_offset);
132   GrowableArray<ScopeValue*>* decode_object_values(int decode_offset);
133 
134   DebugInfoReadStream* stream_at(int decode_offset) const;
135 
136 
137  public:
138   // Verification
139   void verify();
140 
141 #ifndef PRODUCT
142  public:
143   // Printing support
144   void print_on(outputStream* st) const;
145   void print_on(outputStream* st, PcDesc* pd) const;
146   void print_value_on(outputStream* st) const;
147 #endif
148 };
149 
150 #endif // SHARE_CODE_SCOPEDESC_HPP