1 /*
2 * Copyright (c) 1997, 2024, 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.
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23 */
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
43 public:
44 SimpleScopeDesc(nmethod* code, address pc) {
45 PcDesc* pc_desc = code->pc_desc_at(pc);
46 assert(pc_desc != nullptr, "Must be able to find matching PcDesc");
47 // save this here so we only have to look up the PcDesc once
48 DebugInfoReadStream buffer(code, pc_desc->scope_decode_offset());
49 int ignore_sender = buffer.read_int();
50 _method = buffer.read_method();
51 _bci = buffer.read_bci();
52 }
53
54 Method* method() { return _method; }
55 int bci() { return _bci; }
56 };
57
58 // ScopeDescs contain the information that makes source-level debugging of
59 // nmethods possible; each scopeDesc describes a method activation
60
61 class ScopeDesc : public ResourceObj {
62 public:
63 // Constructor
64 ScopeDesc(const nmethod* code, PcDesc* pd, bool ignore_objects = false);
65
66 // Direct access to scope
67 ScopeDesc* at_offset(int decode_offset) { return new ScopeDesc(this, decode_offset); }
68
69 // JVM state
70 Method* method() const { return _method; }
71 int bci() const { return _bci; }
72 bool should_reexecute() const { return _reexecute; }
73 bool rethrow_exception() const { return _rethrow_exception; }
74 bool return_oop() const { return _return_oop; }
75 // Returns true if one or more NoEscape or ArgEscape objects exist in
76 // any of the scopes at compiled pc.
77 bool has_ea_local_in_scope() const { return _has_ea_local_in_scope; }
78 bool arg_escape() const { return _arg_escape; }
79
80 GrowableArray<ScopeValue*>* locals();
81 GrowableArray<ScopeValue*>* expressions();
82 GrowableArray<MonitorValue*>* monitors();
83 GrowableArray<ScopeValue*>* objects();
84
85 // Stack walking, returns nullptr if this is the outer most scope.
86 ScopeDesc* sender() const;
87
88 // Returns where the scope was decoded
89 int decode_offset() const { return _decode_offset; }
90
91 int sender_decode_offset() const { return _sender_decode_offset; }
92
93 // Tells whether sender() returns nullptr
94 bool is_top() const;
95
96 private:
97 void initialize(const ScopeDesc* parent, int decode_offset);
98 // Alternative constructors
99 ScopeDesc(const ScopeDesc* parent);
100 ScopeDesc(const ScopeDesc* parent, int decode_offset);
101
102 // JVM state
103 Method* _method;
104 int _bci;
105 bool _reexecute;
106 bool _rethrow_exception;
107 bool _return_oop;
108 bool _has_ea_local_in_scope; // One or more NoEscape or ArgEscape objects exist in
109 // any of the scopes at compiled pc.
110 bool _arg_escape; // Compiled Java call in youngest scope passes ArgEscape
111
112 // Decoding offsets
113 int _decode_offset;
114 int _sender_decode_offset;
115 int _locals_decode_offset;
116 int _expressions_decode_offset;
117 int _monitors_decode_offset;
118
119 // Object pool
120 GrowableArray<ScopeValue*>* _objects;
121
122 // Nmethod information
123 const nmethod* _code;
124
125 // Decoding operations
126 void decode_body();
127 GrowableArray<ScopeValue*>* decode_scope_values(int decode_offset);
128 GrowableArray<MonitorValue*>* decode_monitor_values(int decode_offset);
129 GrowableArray<ScopeValue*>* decode_object_values(int decode_offset);
130
131 DebugInfoReadStream* stream_at(int decode_offset) const;
132
133
134 public:
135 // Verification
136 void verify();
137 GrowableArray<ScopeValue*>* objects_to_rematerialize(frame& frm, RegisterMap& map);
138
139 #ifndef PRODUCT
140 public:
141 // Printing support
142 void print_on(outputStream* st) const;
143 void print_on(outputStream* st, PcDesc* pd) const;
144 void print_value_on(outputStream* st) const;
145 #endif
146 };
147
148 #endif // SHARE_CODE_SCOPEDESC_HPP