1 /*
2 * Copyright (c) 2000, 2016, 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.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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23 */
24
25 #ifndef SHARE_VM_RUNTIME_VMSTRUCTS_HPP
26 #define SHARE_VM_RUNTIME_VMSTRUCTS_HPP
27
28 #include "utilities/debug.hpp"
29 #ifdef COMPILER1
30 #include "c1/c1_Runtime1.hpp"
31 #endif
32
33 // This table encapsulates the debugging information required by the
34 // serviceability agent in order to run. Specifically, we need to
35 // understand the layout of certain C data structures (offsets, in
36 // bytes, of their fields.)
37 //
38 // There are alternatives for the design of this mechanism, including
39 // parsing platform-specific debugging symbols from a debug build into
40 // a program database. While this current mechanism can be considered
41 // to be a workaround for the inability to debug arbitrary C and C++
42 // programs at the present time, it does have certain advantages.
43 // First, it is platform-independent, which will vastly simplify the
44 // initial bringup of the system both now and on future platforms.
45 // Second, it is embedded within the VM, as opposed to being in a
46 // separate program database; experience has shown that whenever
47 // portions of a system are decoupled, version skew is problematic.
48 // Third, generating a program database, for example for a product
49 // build, would probably require two builds to be done: the desired
50 // product build as well as an intermediary build with the PRODUCT
51 // flag turned on but also compiled with -g, leading to a doubling of
52 // the time required to get a serviceability agent-debuggable product
53 // build. Fourth, and very significantly, this table probably
54 // preserves more information about field types than stabs do; for
55 // example, it preserves the fact that a field is a "jlong" rather
56 // than transforming the type according to the typedef in jni_md.h,
57 // which allows the Java-side code to identify "Java-sized" fields in
58 // C++ data structures. If the symbol parsing mechanism was redone
59 // using stabs, it might still be necessary to have a table somewhere
60 // containing this information.
61 //
62 // Do not change the sizes or signedness of the integer values in
63 // these data structures; they are fixed over in the serviceability
64 // agent's Java code (for bootstrapping).
65
66 typedef struct {
67 const char* typeName; // The type name containing the given field (example: "Klass")
68 const char* fieldName; // The field name within the type (example: "_name")
69 const char* typeString; // Quoted name of the type of this field (example: "Symbol*";
70 // parsed in Java to ensure type correctness
71 int32_t isStatic; // Indicates whether following field is an offset or an address
72 uint64_t offset; // Offset of field within structure; only used for nonstatic fields
73 void* address; // Address of field; only used for static fields
74 // ("offset" can not be reused because of apparent SparcWorks compiler bug
75 // in generation of initializer data)
76 } VMStructEntry;
77
78 typedef struct {
79 const char* typeName; // Type name (example: "Method")
80 const char* superclassName; // Superclass name, or null if none (example: "oopDesc")
81 int32_t isOopType; // Does this type represent an oop typedef? (i.e., "Method*" or
82 // "Klass*", but NOT "Method")
83 int32_t isIntegerType; // Does this type represent an integer type (of arbitrary size)?
84 int32_t isUnsigned; // If so, is it unsigned?
85 uint64_t size; // Size, in bytes, of the type
86 } VMTypeEntry;
87
88 typedef struct {
89 const char* name; // Name of constant (example: "_thread_in_native")
90 int32_t value; // Value of constant
91 } VMIntConstantEntry;
92
93 typedef struct {
94 const char* name; // Name of constant (example: "_thread_in_native")
95 uint64_t value; // Value of constant
96 } VMLongConstantEntry;
97
98 typedef struct {
99 const char* name; // Name of address (example: "SharedRuntime::register_finalizer")
100 void* value; // Value of address
101 } VMAddressEntry;
102
103 // This class is a friend of most classes, to be able to access
104 // private fields
105 class VMStructs {
106 public:
107 // The last entry is identified over in the serviceability agent by
108 // the fact that it has a NULL fieldName
109 static VMStructEntry localHotSpotVMStructs[];
110 // The function to get localHotSpotVMStructs length
111 static size_t localHotSpotVMStructsLength();
112
113 // The last entry is identified over in the serviceability agent by
114 // the fact that it has a NULL typeName
115 static VMTypeEntry localHotSpotVMTypes[];
116 // The function to get localHotSpotVMTypes length
117 static size_t localHotSpotVMTypesLength();
118
119 // Table of integer constants required by the serviceability agent.
120 // The last entry is identified over in the serviceability agent by
121 // the fact that it has a NULL typeName
122 static VMIntConstantEntry localHotSpotVMIntConstants[];
123 // The function to get localHotSpotVMIntConstants length
124 static size_t localHotSpotVMIntConstantsLength();
125
126 // Table of long constants required by the serviceability agent.
127 // The last entry is identified over in the serviceability agent by
128 // the fact that it has a NULL typeName
129 static VMLongConstantEntry localHotSpotVMLongConstants[];
130 // The function to get localHotSpotVMIntConstants length
131 static size_t localHotSpotVMLongConstantsLength();
132
133 /**
134 * Table of addresses.
135 */
136 static VMAddressEntry localHotSpotVMAddresses[];
137
138 // This is used to run any checking code necessary for validation of
139 // the data structure (debug build only)
140 static void init();
141
142 #ifndef PRODUCT
143 // Execute unit tests
144 static void test();
145 #endif
146
147 private:
148 // Look up a type in localHotSpotVMTypes using strcmp() (debug build only).
149 // Returns 1 if found, 0 if not.
150 // debug_only(static int findType(const char* typeName);)
151 static int findType(const char* typeName);
152 };
153
154 // This utility macro quotes the passed string
155 #define QUOTE(x) #x
156
157 //--------------------------------------------------------------------------------
158 // VMStructEntry macros
159 //
160
161 // This macro generates a VMStructEntry line for a nonstatic field
162 #define GENERATE_NONSTATIC_VM_STRUCT_ENTRY(typeName, fieldName, type) \
163 { QUOTE(typeName), QUOTE(fieldName), QUOTE(type), 0, offset_of(typeName, fieldName), NULL },
164
165 // This macro generates a VMStructEntry line for a static field
166 #define GENERATE_STATIC_VM_STRUCT_ENTRY(typeName, fieldName, type) \
167 { QUOTE(typeName), QUOTE(fieldName), QUOTE(type), 1, 0, &typeName::fieldName },
168
169 // This macro generates a VMStructEntry line for a static pointer volatile field,
170 // e.g.: "static ObjectMonitor * volatile gBlockList;"
171 #define GENERATE_STATIC_PTR_VOLATILE_VM_STRUCT_ENTRY(typeName, fieldName, type) \
172 { QUOTE(typeName), QUOTE(fieldName), QUOTE(type), 1, 0, (void *)&typeName::fieldName },
173
174 // This macro generates a VMStructEntry line for an unchecked
175 // nonstatic field, in which the size of the type is also specified.
176 // The type string is given as NULL, indicating an "opaque" type.
177 #define GENERATE_UNCHECKED_NONSTATIC_VM_STRUCT_ENTRY(typeName, fieldName, size) \
178 { QUOTE(typeName), QUOTE(fieldName), NULL, 0, offset_of(typeName, fieldName), NULL },
179
180 // This macro generates a VMStructEntry line for an unchecked
181 // static field, in which the size of the type is also specified.
182 // The type string is given as NULL, indicating an "opaque" type.
183 #define GENERATE_UNCHECKED_STATIC_VM_STRUCT_ENTRY(typeName, fieldName, size) \
184 { QUOTE(typeName), QUOTE(fieldName), NULL, 1, 0, (void*) &typeName::fieldName },
185
186 // This macro generates the sentinel value indicating the end of the list
187 #define GENERATE_VM_STRUCT_LAST_ENTRY() \
188 { NULL, NULL, NULL, 0, 0, NULL }
189
190 // This macro checks the type of a VMStructEntry by comparing pointer types
191 #define CHECK_NONSTATIC_VM_STRUCT_ENTRY(typeName, fieldName, type) \
192 {typeName *dummyObj = NULL; type* dummy = &dummyObj->fieldName; \
193 assert(offset_of(typeName, fieldName) < sizeof(typeName), "Illegal nonstatic struct entry, field offset too large"); }
194
195 // This macro checks the type of a volatile VMStructEntry by comparing pointer types
196 #define CHECK_VOLATILE_NONSTATIC_VM_STRUCT_ENTRY(typeName, fieldName, type) \
197 {typedef type dummyvtype; typeName *dummyObj = NULL; volatile dummyvtype* dummy = &dummyObj->fieldName; }
198
199 // This macro checks the type of a static VMStructEntry by comparing pointer types
200 #define CHECK_STATIC_VM_STRUCT_ENTRY(typeName, fieldName, type) \
201 {type* dummy = &typeName::fieldName; }
202
203 // This macro checks the type of a static pointer volatile VMStructEntry by comparing pointer types,
204 // e.g.: "static ObjectMonitor * volatile gBlockList;"
205 #define CHECK_STATIC_PTR_VOLATILE_VM_STRUCT_ENTRY(typeName, fieldName, type) \
206 {type volatile * dummy = &typeName::fieldName; }
207
208 // This macro ensures the type of a field and its containing type are
209 // present in the type table. The assertion string is shorter than
210 // preferable because (incredibly) of a bug in Solstice NFS client
211 // which seems to prevent very long lines from compiling. This assertion
212 // means that an entry in VMStructs::localHotSpotVMStructs[] was not
213 // found in VMStructs::localHotSpotVMTypes[].
214 #define ENSURE_FIELD_TYPE_PRESENT(typeName, fieldName, type) \
215 { assert(findType(QUOTE(typeName)) != 0, "type \"" QUOTE(typeName) "\" not found in type table"); \
216 assert(findType(QUOTE(type)) != 0, "type \"" QUOTE(type) "\" not found in type table"); }
217
218 // This is a no-op macro for unchecked fields
219 #define CHECK_NO_OP(a, b, c)
220
221
222 //--------------------------------------------------------------------------------
223 // VMTypeEntry macros
224 //
225
226 #define GENERATE_VM_TYPE_ENTRY(type, superclass) \
227 { QUOTE(type), QUOTE(superclass), 0, 0, 0, sizeof(type) },
228
229 #define GENERATE_TOPLEVEL_VM_TYPE_ENTRY(type) \
230 { QUOTE(type), NULL, 0, 0, 0, sizeof(type) },
231
232 #define GENERATE_OOP_VM_TYPE_ENTRY(type) \
233 { QUOTE(type), NULL, 1, 0, 0, sizeof(type) },
234
235 #define GENERATE_INTEGER_VM_TYPE_ENTRY(type) \
236 { QUOTE(type), NULL, 0, 1, 0, sizeof(type) },
237
238 #define GENERATE_UNSIGNED_INTEGER_VM_TYPE_ENTRY(type) \
239 { QUOTE(type), NULL, 0, 1, 1, sizeof(type) },
240
241 #define GENERATE_VM_TYPE_LAST_ENTRY() \
242 { NULL, NULL, 0, 0, 0, 0 }
243
244 #define CHECK_VM_TYPE_ENTRY(type, superclass) \
245 { type* dummyObj = NULL; superclass* dummySuperObj = dummyObj; }
246
247 #define CHECK_VM_TYPE_NO_OP(a)
248 #define CHECK_SINGLE_ARG_VM_TYPE_NO_OP(a)
249
250
251 //--------------------------------------------------------------------------------
252 // VMIntConstantEntry macros
253 //
254
255 #define GENERATE_VM_INT_CONSTANT_ENTRY(name) \
256 { QUOTE(name), (int32_t) name },
257
258 #define GENERATE_VM_INT_CONSTANT_WITH_VALUE_ENTRY(name, value) \
259 { (name), (int32_t)(value) },
260
261 #define GENERATE_PREPROCESSOR_VM_INT_CONSTANT_ENTRY(name, value) \
262 { name, (int32_t) value },
263
264 // This macro generates the sentinel value indicating the end of the list
265 #define GENERATE_VM_INT_CONSTANT_LAST_ENTRY() \
266 { NULL, 0 }
267
268
269 //--------------------------------------------------------------------------------
270 // VMLongConstantEntry macros
271 //
272
273 #define GENERATE_VM_LONG_CONSTANT_ENTRY(name) \
274 { QUOTE(name), name },
275
276 #define GENERATE_PREPROCESSOR_VM_LONG_CONSTANT_ENTRY(name, value) \
277 { name, value },
278
279 // This macro generates the sentinel value indicating the end of the list
280 #define GENERATE_VM_LONG_CONSTANT_LAST_ENTRY() \
281 { NULL, 0 }
282
283
284 //--------------------------------------------------------------------------------
285 // VMAddressEntry macros
286 //
287
288 #define GENERATE_VM_ADDRESS_ENTRY(name) \
289 { QUOTE(name), (void*) (name) },
290
291 #define GENERATE_PREPROCESSOR_VM_ADDRESS_ENTRY(name, value) \
292 { name, (void*) (value) },
293
294 #define GENERATE_VM_FUNCTION_ENTRY(name) \
295 { QUOTE(name), CAST_FROM_FN_PTR(void*, &(name)) },
296
297 // This macro generates the sentinel value indicating the end of the list
298 #define GENERATE_VM_ADDRESS_LAST_ENTRY() \
299 { NULL, NULL }
300
301 #endif // SHARE_VM_RUNTIME_VMSTRUCTS_HPP