diff -r 000000000000 -r f90c822e73f8 src/share/vm/runtime/vmStructs.hpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/runtime/vmStructs.hpp Wed Apr 27 01:25:04 2016 +0800 @@ -0,0 +1,136 @@ +/* + * Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + * + */ + +#ifndef SHARE_VM_RUNTIME_VMSTRUCTS_HPP +#define SHARE_VM_RUNTIME_VMSTRUCTS_HPP + +#include "utilities/debug.hpp" +#ifdef COMPILER1 +#include "c1/c1_Runtime1.hpp" +#endif + +// This table encapsulates the debugging information required by the +// serviceability agent in order to run. Specifically, we need to +// understand the layout of certain C data structures (offsets, in +// bytes, of their fields.) +// +// There are alternatives for the design of this mechanism, including +// parsing platform-specific debugging symbols from a debug build into +// a program database. While this current mechanism can be considered +// to be a workaround for the inability to debug arbitrary C and C++ +// programs at the present time, it does have certain advantages. +// First, it is platform-independent, which will vastly simplify the +// initial bringup of the system both now and on future platforms. +// Second, it is embedded within the VM, as opposed to being in a +// separate program database; experience has shown that whenever +// portions of a system are decoupled, version skew is problematic. +// Third, generating a program database, for example for a product +// build, would probably require two builds to be done: the desired +// product build as well as an intermediary build with the PRODUCT +// flag turned on but also compiled with -g, leading to a doubling of +// the time required to get a serviceability agent-debuggable product +// build. Fourth, and very significantly, this table probably +// preserves more information about field types than stabs do; for +// example, it preserves the fact that a field is a "jlong" rather +// than transforming the type according to the typedef in jni_md.h, +// which allows the Java-side code to identify "Java-sized" fields in +// C++ data structures. If the symbol parsing mechanism was redone +// using stabs, it might still be necessary to have a table somewhere +// containing this information. +// +// Do not change the sizes or signedness of the integer values in +// these data structures; they are fixed over in the serviceability +// agent's Java code (for bootstrapping). + +typedef struct { + const char* typeName; // The type name containing the given field (example: "Klass") + const char* fieldName; // The field name within the type (example: "_name") + const char* typeString; // Quoted name of the type of this field (example: "Symbol*"; + // parsed in Java to ensure type correctness + int32_t isStatic; // Indicates whether following field is an offset or an address + uint64_t offset; // Offset of field within structure; only used for nonstatic fields + void* address; // Address of field; only used for static fields + // ("offset" can not be reused because of apparent SparcWorks compiler bug + // in generation of initializer data) +} VMStructEntry; + +typedef struct { + const char* typeName; // Type name (example: "Method") + const char* superclassName; // Superclass name, or null if none (example: "oopDesc") + int32_t isOopType; // Does this type represent an oop typedef? (i.e., "Method*" or + // "Klass*", but NOT "Method") + int32_t isIntegerType; // Does this type represent an integer type (of arbitrary size)? + int32_t isUnsigned; // If so, is it unsigned? + uint64_t size; // Size, in bytes, of the type +} VMTypeEntry; + +typedef struct { + const char* name; // Name of constant (example: "_thread_in_native") + int32_t value; // Value of constant +} VMIntConstantEntry; + +typedef struct { + const char* name; // Name of constant (example: "_thread_in_native") + uint64_t value; // Value of constant +} VMLongConstantEntry; + +// This class is a friend of most classes, to be able to access +// private fields +class VMStructs { +public: + // The last entry is identified over in the serviceability agent by + // the fact that it has a NULL fieldName + static VMStructEntry localHotSpotVMStructs[]; + + // The last entry is identified over in the serviceability agent by + // the fact that it has a NULL typeName + static VMTypeEntry localHotSpotVMTypes[]; + + // Table of integer constants required by the serviceability agent. + // The last entry is identified over in the serviceability agent by + // the fact that it has a NULL typeName + static VMIntConstantEntry localHotSpotVMIntConstants[]; + + // Table of long constants required by the serviceability agent. + // The last entry is identified over in the serviceability agent by + // the fact that it has a NULL typeName + static VMLongConstantEntry localHotSpotVMLongConstants[]; + + // This is used to run any checking code necessary for validation of + // the data structure (debug build only) + static void init(); + +#ifndef PRODUCT + // Execute unit tests + static void test(); +#endif + +private: + // Look up a type in localHotSpotVMTypes using strcmp() (debug build only). + // Returns 1 if found, 0 if not. + // debug_only(static int findType(const char* typeName);) + static int findType(const char* typeName); +}; + +#endif // SHARE_VM_RUNTIME_VMSTRUCTS_HPP