/*

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 * 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

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 */

#ifndef SHARE_RUNTIME_VMSTRUCTS_HPP

#define SHARE_RUNTIME_VMSTRUCTS_HPP

#include "utilities/debug.hpp"

#include "utilities/globalDefinitions.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 solstudio 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;

typedef struct {

  const char* name;                // Name of address (example: "SharedRuntime::register_finalizer")

  void* value;                     // Value of address

} VMAddressEntry;

// 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 function to get localHotSpotVMStructs length

  static size_t localHotSpotVMStructsLength();

  // The last entry is identified over in the serviceability agent by

  // the fact that it has a NULL typeName

  static VMTypeEntry   localHotSpotVMTypes[];

  // The function to get localHotSpotVMTypes length

  static size_t localHotSpotVMTypesLength();

  // 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[];

  // The function to get localHotSpotVMIntConstants length

  static size_t localHotSpotVMIntConstantsLength();

  // 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[];

  // The function to get localHotSpotVMIntConstants length

  static size_t localHotSpotVMLongConstantsLength();

  /**

   * Table of addresses.

   */

  static VMAddressEntry localHotSpotVMAddresses[];

  // 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);

};

// This utility macro quotes the passed string

#define QUOTE(x) #x

//--------------------------------------------------------------------------------

// VMStructEntry macros

//

// This macro generates a VMStructEntry line for a nonstatic field

#define GENERATE_NONSTATIC_VM_STRUCT_ENTRY(typeName, fieldName, type)              \

 { QUOTE(typeName), QUOTE(fieldName), QUOTE(type), 0, offset_of(typeName, fieldName), NULL },

// This macro generates a VMStructEntry line for a static field

#define GENERATE_STATIC_VM_STRUCT_ENTRY(typeName, fieldName, type)                 \

 { QUOTE(typeName), QUOTE(fieldName), QUOTE(type), 1, 0, &typeName::fieldName },

// This macro generates a VMStructEntry line for a static pointer volatile field,

// e.g.: "static ObjectMonitor * volatile g_block_list;"

#define GENERATE_STATIC_PTR_VOLATILE_VM_STRUCT_ENTRY(typeName, fieldName, type)    \

 { QUOTE(typeName), QUOTE(fieldName), QUOTE(type), 1, 0, (void *)&typeName::fieldName },

// This macro generates a VMStructEntry line for an unchecked

// nonstatic field, in which the size of the type is also specified.

// The type string is given as NULL, indicating an "opaque" type.

#define GENERATE_UNCHECKED_NONSTATIC_VM_STRUCT_ENTRY(typeName, fieldName, size)    \

  { QUOTE(typeName), QUOTE(fieldName), NULL, 0, offset_of(typeName, fieldName), NULL },

// This macro generates a VMStructEntry line for an unchecked

// static field, in which the size of the type is also specified.

// The type string is given as NULL, indicating an "opaque" type.

#define GENERATE_UNCHECKED_STATIC_VM_STRUCT_ENTRY(typeName, fieldName, size)       \

 { QUOTE(typeName), QUOTE(fieldName), NULL, 1, 0, (void*) &typeName::fieldName },

// This macro generates the sentinel value indicating the end of the list

#define GENERATE_VM_STRUCT_LAST_ENTRY() \

 { NULL, NULL, NULL, 0, 0, NULL }

// This macro checks the type of a VMStructEntry by comparing pointer types

#define CHECK_NONSTATIC_VM_STRUCT_ENTRY(typeName, fieldName, type)                 \

 {typeName *dummyObj = NULL; type* dummy = &dummyObj->fieldName;                   \

  assert(offset_of(typeName, fieldName) < sizeof(typeName), "Illegal nonstatic struct entry, field offset too large"); }

// This macro checks the type of a volatile VMStructEntry by comparing pointer types

#define CHECK_VOLATILE_NONSTATIC_VM_STRUCT_ENTRY(typeName, fieldName, type)        \

 {typedef type dummyvtype; typeName *dummyObj = NULL; volatile dummyvtype* dummy = &dummyObj->fieldName; }

// This macro checks the type of a static VMStructEntry by comparing pointer types

#define CHECK_STATIC_VM_STRUCT_ENTRY(typeName, fieldName, type)                    \

 {type* dummy = &typeName::fieldName; }

// This macro checks the type of a static pointer volatile VMStructEntry by comparing pointer types,

// e.g.: "static ObjectMonitor * volatile g_block_list;"

#define CHECK_STATIC_PTR_VOLATILE_VM_STRUCT_ENTRY(typeName, fieldName, type)       \

 {type volatile * dummy = &typeName::fieldName; }

// This macro ensures the type of a field and its containing type are

// present in the type table. The assertion string is shorter than

// preferable because (incredibly) of a bug in Solstice NFS client

// which seems to prevent very long lines from compiling. This assertion

// means that an entry in VMStructs::localHotSpotVMStructs[] was not

// found in VMStructs::localHotSpotVMTypes[].

#define ENSURE_FIELD_TYPE_PRESENT(typeName, fieldName, type)                       \

 { assert(findType(QUOTE(typeName)) != 0, "type \"" QUOTE(typeName) "\" not found in type table"); \

   assert(findType(QUOTE(type)) != 0, "type \"" QUOTE(type) "\" not found in type table"); }

// This is a no-op macro for unchecked fields

#define CHECK_NO_OP(a, b, c)

//--------------------------------------------------------------------------------

// VMTypeEntry macros

//

#define GENERATE_VM_TYPE_ENTRY(type, superclass) \

 { QUOTE(type), QUOTE(superclass), 0, 0, 0, sizeof(type) },

#define GENERATE_TOPLEVEL_VM_TYPE_ENTRY(type) \

 { QUOTE(type), NULL,              0, 0, 0, sizeof(type) },

#define GENERATE_OOP_VM_TYPE_ENTRY(type) \

 { QUOTE(type), NULL,              1, 0, 0, sizeof(type) },

#define GENERATE_INTEGER_VM_TYPE_ENTRY(type) \

 { QUOTE(type), NULL,              0, 1, 0, sizeof(type) },

#define GENERATE_UNSIGNED_INTEGER_VM_TYPE_ENTRY(type) \

 { QUOTE(type), NULL,              0, 1, 1, sizeof(type) },

#define GENERATE_VM_TYPE_LAST_ENTRY() \

 { NULL, NULL, 0, 0, 0, 0 }

#define CHECK_VM_TYPE_ENTRY(type, superclass) \

 { type* dummyObj = NULL; superclass* dummySuperObj = dummyObj; }

#define CHECK_VM_TYPE_NO_OP(a)

#define CHECK_SINGLE_ARG_VM_TYPE_NO_OP(a)

//--------------------------------------------------------------------------------

// VMIntConstantEntry macros

//

#define GENERATE_VM_INT_CONSTANT_ENTRY(name) \

 { QUOTE(name), (int32_t) name },

#define GENERATE_VM_INT_CONSTANT_WITH_VALUE_ENTRY(name, value) \

 { (name), (int32_t)(value) },

#define GENERATE_PREPROCESSOR_VM_INT_CONSTANT_ENTRY(name, value) \

 { name, (int32_t) value },

// This macro generates the sentinel value indicating the end of the list

#define GENERATE_VM_INT_CONSTANT_LAST_ENTRY() \

 { NULL, 0 }

//--------------------------------------------------------------------------------

// VMLongConstantEntry macros

//

#define GENERATE_VM_LONG_CONSTANT_ENTRY(name) \

  { QUOTE(name), name },

#define GENERATE_PREPROCESSOR_VM_LONG_CONSTANT_ENTRY(name, value) \

  { name, value },

// This macro generates the sentinel value indicating the end of the list

#define GENERATE_VM_LONG_CONSTANT_LAST_ENTRY() \

 { NULL, 0 }

//--------------------------------------------------------------------------------

// VMAddressEntry macros

//

#define GENERATE_VM_ADDRESS_ENTRY(name) \

  { QUOTE(name), (void*) (name) },

#define GENERATE_PREPROCESSOR_VM_ADDRESS_ENTRY(name, value) \

  { name, (void*) (value) },

#define GENERATE_VM_FUNCTION_ENTRY(name) \

  { QUOTE(name), CAST_FROM_FN_PTR(void*, &(name)) },

// This macro generates the sentinel value indicating the end of the list

#define GENERATE_VM_ADDRESS_LAST_ENTRY() \

 { NULL, NULL }

#endif // SHARE_RUNTIME_VMSTRUCTS_HPP