1 /*
2 * Copyright (c) 1997, 2020, 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_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 bool return_scalarized() const { return _return_scalarized; }
79 // Returns true if one or more NoEscape or ArgEscape objects exist in
80 // any of the scopes at compiled pc.
81 bool has_ea_local_in_scope() const { return _has_ea_local_in_scope; }
82 bool arg_escape() const { return _arg_escape; }
83
84 GrowableArray<ScopeValue*>* locals();
85 GrowableArray<ScopeValue*>* expressions();
86 GrowableArray<MonitorValue*>* monitors();
87 GrowableArray<ScopeValue*>* objects();
88
89 // Stack walking, returns NULL if this is the outer most scope.
90 ScopeDesc* sender() const;
91
92 // Returns where the scope was decoded
93 int decode_offset() const { return _decode_offset; }
94
95 int sender_decode_offset() const { return _sender_decode_offset; }
96
97 // Tells whether sender() returns NULL
98 bool is_top() const;
99
100 private:
101 void initialize(const ScopeDesc* parent, int decode_offset);
102 // Alternative constructors
103 ScopeDesc(const ScopeDesc* parent);
104 ScopeDesc(const ScopeDesc* parent, int decode_offset);
105
106 // JVM state
107 Method* _method;
108 int _bci;
109 bool _reexecute;
110 bool _rethrow_exception;
111 bool _return_oop;
112 bool _return_scalarized;
113 bool _has_ea_local_in_scope; // One or more NoEscape or ArgEscape objects exist in
114 // any of the scopes at compiled pc.
115 bool _arg_escape; // Compiled Java call in youngest scope passes ArgEscape
116 // Decoding offsets
117 int _decode_offset;
118 int _sender_decode_offset;
119 int _locals_decode_offset;
120 int _expressions_decode_offset;
121 int _monitors_decode_offset;
122
123 // Object pool
124 GrowableArray<ScopeValue*>* _objects;
125
126 // Nmethod information
127 const CompiledMethod* _code;
128
129 // Decoding operations
130 void decode_body();
131 GrowableArray<ScopeValue*>* decode_scope_values(int decode_offset);
132 GrowableArray<MonitorValue*>* decode_monitor_values(int decode_offset);
133 GrowableArray<ScopeValue*>* decode_object_values(int decode_offset);
134
135 DebugInfoReadStream* stream_at(int decode_offset) const;
136
137
138 public:
139 // Verification
140 void verify();
141
142 #ifndef PRODUCT
143 public:
144 // Printing support
145 void print_on(outputStream* st) const;
146 void print_on(outputStream* st, PcDesc* pd) const;
147 void print_value_on(outputStream* st) const;
148 #endif
149 };
150
151 #endif // SHARE_CODE_SCOPEDESC_HPP