1 /*
2 * Copyright (c) 1998, 2025, 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
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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 *
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23 */
24
25 #ifndef SHARE_CODE_DEBUGINFOREC_HPP
26 #define SHARE_CODE_DEBUGINFOREC_HPP
27
28 #include "ci/ciClassList.hpp"
29 #include "ci/ciInstanceKlass.hpp"
30 #include "ci/ciMethod.hpp"
31 #include "code/debugInfo.hpp"
32 #include "code/location.hpp"
33 #include "code/pcDesc.hpp"
34 #include "oops/oop.hpp"
35 #include "utilities/growableArray.hpp"
36
37 class OopMap;
38 class OopMapSet;
39
40 //** The DebugInformationRecorder collects debugging information
41 // for a compiled method.
42 // Debugging information is used for:
43 // - garbage collecting compiled frames
44 // - stack tracing across compiled frames
45 // - deoptimizating compiled frames
46 //
47 // The implementation requires the compiler to use the recorder
48 // in the following order:
49 // 1) Describe debug information for safepoints at increasing addresses.
50 // a) Add safepoint entry (use add_safepoint or add_non_safepoint)
51 // b) Describe scopes for that safepoint
52 // - create locals if needed (use create_scope_values)
53 // - create expressions if needed (use create_scope_values)
54 // - create monitor stack if needed (use create_monitor_values)
55 // - describe scope (use describe_scope)
56 // "repeat last four steps for all scopes"
57 // "outer most scope first and inner most scope last"
58 // NB: nodes from create_scope_values and create_locations
59 // can be reused for simple sharing.
60 // - mark the end of the scopes (end_safepoint or end_non_safepoint)
61 // 2) Use oop_size, metadata_size, data_size, pcs_size to create the nmethod
62 // and finally migrate the debugging information into the nmethod
63 // by calling copy_to.
64
65 class DebugToken; // Opaque datatype for stored:
66 // - GrowableArray<ScopeValue*>
67 // - GrowableArray<MonitorValue*>
68
69 // Alias for InvocationEntryBci.
70 // Both constants are used for a pseudo-BCI which refers
71 // to the state just _before_ a method is entered.
72 // SynchronizationEntryBCI is used where the emphasis
73 // is on the implicit monitorenter of a synchronized method.
74 const int SynchronizationEntryBCI = InvocationEntryBci;
75
76 class DIR_Chunk; // private class, a nugget of collected information
77
78 class DebugInformationRecorder: public ResourceObj {
79 public:
80 // constructor
81 DebugInformationRecorder(OopRecorder* oop_recorder);
82 DebugInformationRecorder(OopRecorder* oop_recorder, int data_size, int pcs_length);
83
84 // adds an oopmap at a specific offset
85 void add_oopmap(int pc_offset, OopMap* map);
86
87 // adds a jvm mapping at pc-offset, for a safepoint only
88 void add_safepoint(int pc_offset, OopMap* map);
89
90 // adds a jvm mapping at pc-offset, for a non-safepoint (profile point)
91 void add_non_safepoint(int pc_offset);
92
93 // Describes debugging information for a scope at the given pc_offset.
94 // Calls must be in non-decreasing order of pc_offset.
95 // If there are several calls at a single pc_offset,
96 // then they occur in the same order as they were performed by the JVM,
97 // with the most recent (innermost) call being described last.
98 // For a safepoint, the pc_offset must have been mentioned
99 // previously by add_safepoint.
100 // Otherwise, the pc_offset must have been mentioned previously
101 // by add_non_safepoint, and the locals, expressions, and monitors
102 // must all be null.
103 void describe_scope(int pc_offset,
104 const methodHandle& methodH,
105 ciMethod* method,
106 int bci,
107 bool reexecute,
108 bool rethrow_exception = false,
109 bool return_oop = false,
110 bool has_ea_local_in_scope = false,
111 bool arg_escape = false,
112 DebugToken* locals = nullptr,
113 DebugToken* expressions = nullptr,
114 DebugToken* monitors = nullptr);
115
116
117 void dump_object_pool(GrowableArray<ScopeValue*>* objects);
118
119 // This call must follow every add_safepoint,
120 // after any intervening describe_scope calls.
121 void end_safepoint(int pc_offset) { end_scopes(pc_offset, true); }
122 void end_non_safepoint(int pc_offset) { end_scopes(pc_offset, false); }
123
124 // helper functions for describe_scope to enable sharing
125 DebugToken* create_scope_values(GrowableArray<ScopeValue*>* values);
126 DebugToken* create_monitor_values(GrowableArray<MonitorValue*>* monitors);
127
128 // returns the size of the generated scopeDescs.
129 int data_size();
130 int pcs_size();
131 int oop_size() { return oop_recorder()->oop_size(); }
132 int metadata_size() { return oop_recorder()->metadata_size(); }
133
134 // copy the generated debugging information to nmethod
135 void copy_to(nmethod* nm);
136
137 // verifies the debug information
138 void verify(const nmethod* code);
139
140 static void print_statistics() PRODUCT_RETURN;
141
142 // Method for setting oopmaps to temporarily preserve old handling of oopmaps
143 OopMapSet *_oopmaps;
144 void set_oopmaps(OopMapSet *oopmaps) { _oopmaps = oopmaps; }
145
146 OopRecorder* oop_recorder() { return _oop_recorder; }
147
148 int last_pc_offset() { return last_pc()->pc_offset(); }
149
150 bool recording_non_safepoints() { return _recording_non_safepoints; }
151
152 PcDesc* pcs() const { return _pcs; }
153 int pcs_length() const { return _pcs_length; }
154
155 DebugInfoWriteStream* stream() const { return _stream; }
156
157
158 private:
159 friend class ScopeDesc;
160 friend class vframeStreamCommon;
161 friend class DIR_Chunk;
162
163 // True if we are recording non-safepoint scopes.
164 // This flag is set if DebugNonSafepoints is true, or if
165 // JVMTI post_compiled_method_load events are enabled.
166 const bool _recording_non_safepoints;
167
168 DebugInfoWriteStream* _stream;
169
170 OopRecorder* _oop_recorder;
171
172 // Scopes that have been described so far.
173 GrowableArray<DIR_Chunk*>* _all_chunks;
174 DIR_Chunk* _next_chunk;
175 DIR_Chunk* _next_chunk_limit;
176
177 #ifdef ASSERT
178 enum { rs_null, rs_safepoint, rs_non_safepoint };
179 int _recording_state;
180 #endif
181
182 PcDesc* _pcs;
183 int _pcs_size;
184 int _pcs_length;
185 // Note: Would use GrowableArray<PcDesc>, but structs are not supported.
186
187 // PC of most recent real safepoint before the current one,
188 // updated after end_scopes.
189 int _prev_safepoint_pc;
190
191 PcDesc* last_pc() {
192 guarantee(_pcs_length > 0, "a safepoint must be declared already");
193 return &_pcs[_pcs_length-1];
194 }
195 PcDesc* prev_pc() {
196 guarantee(_pcs_length > 1, "a safepoint must be declared already");
197 return &_pcs[_pcs_length-2];
198 }
199 void add_new_pc_offset(int pc_offset);
200 void end_scopes(int pc_offset, bool is_safepoint);
201
202 int serialize_monitor_values(GrowableArray<MonitorValue*>* monitors);
203 int serialize_scope_values(GrowableArray<ScopeValue*>* values);
204 int find_sharable_decode_offset(int stream_offset);
205
206 #ifndef PRODUCT
207 bool recorders_frozen();
208 void mark_recorders_frozen();
209 #endif // PRODUCT
210
211 public:
212 enum { serialized_null = 0 };
213 };
214
215 #endif // SHARE_CODE_DEBUGINFOREC_HPP