--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/oops/constMethod.hpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,564 @@
+/*
+ * Copyright (c) 2003, 2017, 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_OOPS_CONSTMETHODOOP_HPP
+#define SHARE_VM_OOPS_CONSTMETHODOOP_HPP
+
+#include "oops/oop.hpp"
+#include "utilities/align.hpp"
+
+// An ConstMethod represents portions of a Java method which are not written to after
+// the classfile is parsed(*see below). This part of the method can be shared across
+// processes in a read-only section with Class Data Sharing (CDS). It's important
+// that this class doesn't have virtual functions because the vptr cannot be shared
+// with CDS.
+//
+// Note that most applications load thousands of methods, so keeping the size of this
+// structure small has a big impact on footprint.
+
+// The actual bytecodes are inlined after the end of the ConstMethod struct.
+//
+// The line number table is compressed and inlined following the byte codes. It is
+// found as the first byte following the byte codes. Note that accessing the line
+// number and local variable tables is not performance critical at all.
+//
+// The checked exceptions table and the local variable table are inlined after the
+// line number table, and indexed from the end of the method. We do not compress the
+// checked exceptions table since the average length is less than 2, and it is used
+// by reflection so access should be fast. We do not bother to compress the local
+// variable table either since it is mostly absent.
+//
+//
+// ConstMethod embedded field layout (after declared fields):
+// [EMBEDDED byte codes]
+// [EMBEDDED compressed linenumber table]
+// (see class CompressedLineNumberReadStream)
+// (note that length is unknown until decompressed)
+// (access flags bit tells whether table is present)
+// (indexed from start of ConstMethod)
+// (elements not necessarily sorted!)
+// [EMBEDDED localvariable table elements + length (length last)]
+// (length is u2, elements are 6-tuples of u2)
+// (see class LocalVariableTableElement)
+// (access flags bit tells whether table is present)
+// (indexed from end of ConstMethod*)
+// [EMBEDDED exception table + length (length last)]
+// (length is u2, elements are 4-tuples of u2)
+// (see class ExceptionTableElement)
+// (access flags bit tells whether table is present)
+// (indexed from end of ConstMethod*)
+// [EMBEDDED checked exceptions elements + length (length last)]
+// (length is u2, elements are u2)
+// (see class CheckedExceptionElement)
+// (access flags bit tells whether table is present)
+// (indexed from end of ConstMethod*)
+// [EMBEDDED method parameters elements + length (length last)]
+// (length is u2, elements are u2, u4 structures)
+// (see class MethodParametersElement)
+// (access flags bit tells whether table is present)
+// (indexed from end of ConstMethod*)
+// [EMBEDDED generic signature index (u2)]
+// (indexed from end of constMethodOop)
+// [EMBEDDED annotations arrays - method, parameter, type, default]
+// pointer to Array<u1> if annotation is present
+//
+// IMPORTANT: If anything gets added here, there need to be changes to
+// ensure that ServicabilityAgent doesn't get broken as a result!
+
+
+// Utility class describing elements in checked exceptions table inlined in Method*.
+class CheckedExceptionElement VALUE_OBJ_CLASS_SPEC {
+ public:
+ u2 class_cp_index;
+};
+
+
+// Utility class describing elements in local variable table inlined in Method*.
+class LocalVariableTableElement VALUE_OBJ_CLASS_SPEC {
+ public:
+ u2 start_bci;
+ u2 length;
+ u2 name_cp_index;
+ u2 descriptor_cp_index;
+ u2 signature_cp_index;
+ u2 slot;
+};
+
+// Utility class describing elements in exception table
+class ExceptionTableElement VALUE_OBJ_CLASS_SPEC {
+ public:
+ u2 start_pc;
+ u2 end_pc;
+ u2 handler_pc;
+ u2 catch_type_index;
+};
+
+// Utility class describing elements in method parameters
+class MethodParametersElement VALUE_OBJ_CLASS_SPEC {
+ public:
+ u2 name_cp_index;
+ u2 flags;
+};
+
+class KlassSizeStats;
+class AdapterHandlerEntry;
+
+// Class to collect the sizes of ConstMethod inline tables
+#define INLINE_TABLES_DO(do_element) \
+ do_element(localvariable_table_length) \
+ do_element(compressed_linenumber_size) \
+ do_element(exception_table_length) \
+ do_element(checked_exceptions_length) \
+ do_element(method_parameters_length) \
+ do_element(generic_signature_index) \
+ do_element(method_annotations_length) \
+ do_element(parameter_annotations_length) \
+ do_element(type_annotations_length) \
+ do_element(default_annotations_length)
+
+#define INLINE_TABLE_DECLARE(sym) int _##sym;
+#define INLINE_TABLE_PARAM(sym) int sym,
+#define INLINE_TABLE_INIT(sym) _##sym(sym),
+#define INLINE_TABLE_NULL(sym) _##sym(0),
+#define INLINE_TABLE_ACCESSOR(sym) int sym() const { return _##sym; }
+
+class InlineTableSizes : StackObj {
+ // declarations
+ INLINE_TABLES_DO(INLINE_TABLE_DECLARE)
+ int _end;
+ public:
+ InlineTableSizes(
+ INLINE_TABLES_DO(INLINE_TABLE_PARAM)
+ int end) :
+ INLINE_TABLES_DO(INLINE_TABLE_INIT)
+ _end(end) {}
+
+ // Default constructor for no inlined tables
+ InlineTableSizes() :
+ INLINE_TABLES_DO(INLINE_TABLE_NULL)
+ _end(0) {}
+
+ // Accessors
+ INLINE_TABLES_DO(INLINE_TABLE_ACCESSOR)
+};
+#undef INLINE_TABLE_ACCESSOR
+#undef INLINE_TABLE_NULL
+#undef INLINE_TABLE_INIT
+#undef INLINE_TABLE_PARAM
+#undef INLINE_TABLE_DECLARE
+
+class ConstMethod : public MetaspaceObj {
+ friend class VMStructs;
+ friend class JVMCIVMStructs;
+
+public:
+ typedef enum { NORMAL, OVERPASS } MethodType;
+
+private:
+ enum {
+ _has_linenumber_table = 0x0001,
+ _has_checked_exceptions = 0x0002,
+ _has_localvariable_table = 0x0004,
+ _has_exception_table = 0x0008,
+ _has_generic_signature = 0x0010,
+ _has_method_parameters = 0x0020,
+ _is_overpass = 0x0040,
+ _has_method_annotations = 0x0080,
+ _has_parameter_annotations = 0x0100,
+ _has_type_annotations = 0x0200,
+ _has_default_annotations = 0x0400
+ };
+
+ // Bit vector of signature
+ // Callers interpret 0=not initialized yet and
+ // -1=too many args to fix, must parse the slow way.
+ // The real initial value is special to account for nonatomicity of 64 bit
+ // loads and stores. This value may updated and read without a lock by
+ // multiple threads, so is volatile.
+ volatile uint64_t _fingerprint;
+
+ // If you add a new field that points to any metaspace object, you
+ // must add this field to ConstMethod::metaspace_pointers_do().
+
+ ConstantPool* _constants; // Constant pool
+
+ // Raw stackmap data for the method
+ Array<u1>* _stackmap_data;
+
+ // Adapter blob (i2c/c2i) for this Method*. Set once when method is linked.
+ union {
+ AdapterHandlerEntry* _adapter;
+ AdapterHandlerEntry** _adapter_trampoline; // see comments around Method::link_method()
+ };
+
+ int _constMethod_size;
+ u2 _flags;
+ u1 _result_type; // BasicType of result
+
+ // Size of Java bytecodes allocated immediately after Method*.
+ u2 _code_size;
+ u2 _name_index; // Method name (index in constant pool)
+ u2 _signature_index; // Method signature (index in constant pool)
+ u2 _method_idnum; // unique identification number for the method within the class
+ // initially corresponds to the index into the methods array.
+ // but this may change with redefinition
+ u2 _max_stack; // Maximum number of entries on the expression stack
+ u2 _max_locals; // Number of local variables used by this method
+ u2 _size_of_parameters; // size of the parameter block (receiver + arguments) in words
+ u2 _orig_method_idnum; // Original unique identification number for the method
+
+ // Constructor
+ ConstMethod(int byte_code_size,
+ InlineTableSizes* sizes,
+ MethodType is_overpass,
+ int size);
+public:
+
+ static ConstMethod* allocate(ClassLoaderData* loader_data,
+ int byte_code_size,
+ InlineTableSizes* sizes,
+ MethodType mt,
+ TRAPS);
+
+ bool is_constMethod() const { return true; }
+
+ // Inlined tables
+ void set_inlined_tables_length(InlineTableSizes* sizes);
+
+ bool has_generic_signature() const
+ { return (_flags & _has_generic_signature) != 0; }
+
+ bool has_linenumber_table() const
+ { return (_flags & _has_linenumber_table) != 0; }
+
+ bool has_checked_exceptions() const
+ { return (_flags & _has_checked_exceptions) != 0; }
+
+ bool has_localvariable_table() const
+ { return (_flags & _has_localvariable_table) != 0; }
+
+ bool has_exception_handler() const
+ { return (_flags & _has_exception_table) != 0; }
+
+ bool has_method_parameters() const
+ { return (_flags & _has_method_parameters) != 0; }
+
+ MethodType method_type() const {
+ return ((_flags & _is_overpass) == 0) ? NORMAL : OVERPASS;
+ }
+
+ void set_method_type(MethodType mt) {
+ if (mt == NORMAL) {
+ _flags &= ~(_is_overpass);
+ } else {
+ _flags |= _is_overpass;
+ }
+ }
+
+ // constant pool
+ ConstantPool* constants() const { return _constants; }
+ void set_constants(ConstantPool* c) { _constants = c; }
+
+ Method* method() const;
+
+ // stackmap table data
+ Array<u1>* stackmap_data() const { return _stackmap_data; }
+ void set_stackmap_data(Array<u1>* sd) { _stackmap_data = sd; }
+ void copy_stackmap_data(ClassLoaderData* loader_data, u1* sd, int length, TRAPS);
+ bool has_stackmap_table() const { return _stackmap_data != NULL; }
+
+ // adapter
+ void set_adapter_entry(AdapterHandlerEntry* adapter) {
+ assert(!is_shared(), "shared methods have fixed adapter_trampoline");
+ _adapter = adapter;
+ }
+ void set_adapter_trampoline(AdapterHandlerEntry** trampoline) {
+ assert(DumpSharedSpaces, "must be");
+ assert(*trampoline == NULL, "must be NULL during dump time, to be initialized at run time");
+ _adapter_trampoline = trampoline;
+ }
+ void update_adapter_trampoline(AdapterHandlerEntry* adapter) {
+ assert(is_shared(), "must be");
+ *_adapter_trampoline = adapter;
+ assert(this->adapter() == adapter, "must be");
+ }
+ AdapterHandlerEntry* adapter() {
+ if (is_shared()) {
+ return *_adapter_trampoline;
+ } else {
+ return _adapter;
+ }
+ }
+
+ void init_fingerprint() {
+ const uint64_t initval = UCONST64(0x8000000000000000);
+ _fingerprint = initval;
+ }
+
+ uint64_t fingerprint() const {
+ // Since reads aren't atomic for 64 bits, if any of the high or low order
+ // word is the initial value, return 0. See init_fingerprint for initval.
+ uint high_fp = (uint)(_fingerprint >> 32);
+ if ((int) _fingerprint == 0 || high_fp == 0x80000000) {
+ return 0L;
+ } else {
+ return _fingerprint;
+ }
+ }
+
+ uint64_t set_fingerprint(uint64_t new_fingerprint) {
+#ifdef ASSERT
+ // Assert only valid if complete/valid 64 bit _fingerprint value is read.
+ uint64_t oldfp = fingerprint();
+#endif // ASSERT
+ _fingerprint = new_fingerprint;
+ assert(oldfp == 0L || new_fingerprint == oldfp,
+ "fingerprint cannot change");
+ assert(((new_fingerprint >> 32) != 0x80000000) && (int)new_fingerprint !=0,
+ "fingerprint should call init to set initial value");
+ return new_fingerprint;
+ }
+
+ // name
+ int name_index() const { return _name_index; }
+ void set_name_index(int index) { _name_index = index; }
+
+ // signature
+ int signature_index() const { return _signature_index; }
+ void set_signature_index(int index) { _signature_index = index; }
+
+ // generics support
+ int generic_signature_index() const {
+ if (has_generic_signature()) {
+ return *generic_signature_index_addr();
+ } else {
+ return 0;
+ }
+ }
+ void set_generic_signature_index(u2 index) {
+ assert(has_generic_signature(), "");
+ u2* addr = generic_signature_index_addr();
+ *addr = index;
+ }
+
+ // Sizing
+ static int header_size() {
+ return align_up((int)sizeof(ConstMethod), wordSize) / wordSize;
+ }
+
+ // Size needed
+ static int size(int code_size, InlineTableSizes* sizes);
+
+ int size() const { return _constMethod_size;}
+ void set_constMethod_size(int size) { _constMethod_size = size; }
+
+ // ConstMethods should be stored in the read-only region of CDS archive.
+ static bool is_read_only_by_default() { return true; }
+
+#if INCLUDE_SERVICES
+ void collect_statistics(KlassSizeStats *sz) const;
+#endif
+
+ // code size
+ int code_size() const { return _code_size; }
+ void set_code_size(int size) {
+ assert(max_method_code_size < (1 << 16),
+ "u2 is too small to hold method code size in general");
+ assert(0 <= size && size <= max_method_code_size, "invalid code size");
+ _code_size = size;
+ }
+
+ // linenumber table - note that length is unknown until decompression,
+ // see class CompressedLineNumberReadStream.
+ u_char* compressed_linenumber_table() const; // not preserved by gc
+ u2* generic_signature_index_addr() const;
+ u2* checked_exceptions_length_addr() const;
+ u2* localvariable_table_length_addr() const;
+ u2* exception_table_length_addr() const;
+ u2* method_parameters_length_addr() const;
+
+ // checked exceptions
+ int checked_exceptions_length() const;
+ CheckedExceptionElement* checked_exceptions_start() const;
+
+ // localvariable table
+ int localvariable_table_length() const;
+ LocalVariableTableElement* localvariable_table_start() const;
+
+ // exception table
+ int exception_table_length() const;
+ ExceptionTableElement* exception_table_start() const;
+
+ // method parameters table
+
+ // This returns -1 if no parameters are present, a non-negative
+ // value otherwise. Note: sometimes, there are 0-length parameters
+ // attributes that must be reported up to the reflection API all the
+ // same.
+ int method_parameters_length() const;
+ MethodParametersElement* method_parameters_start() const;
+
+ // method annotations
+ bool has_method_annotations() const
+ { return (_flags & _has_method_annotations) != 0; }
+
+ bool has_parameter_annotations() const
+ { return (_flags & _has_parameter_annotations) != 0; }
+
+ bool has_type_annotations() const
+ { return (_flags & _has_type_annotations) != 0; }
+
+ bool has_default_annotations() const
+ { return (_flags & _has_default_annotations) != 0; }
+
+
+ AnnotationArray** method_annotations_addr() const;
+ AnnotationArray* method_annotations() const {
+ return has_method_annotations() ? *(method_annotations_addr()) : NULL;
+ }
+ void set_method_annotations(AnnotationArray* anno) {
+ *(method_annotations_addr()) = anno;
+ }
+
+ AnnotationArray** parameter_annotations_addr() const;
+ AnnotationArray* parameter_annotations() const {
+ return has_parameter_annotations() ? *(parameter_annotations_addr()) : NULL;
+ }
+ void set_parameter_annotations(AnnotationArray* anno) {
+ *(parameter_annotations_addr()) = anno;
+ }
+
+ AnnotationArray** type_annotations_addr() const;
+ AnnotationArray* type_annotations() const {
+ return has_type_annotations() ? *(type_annotations_addr()) : NULL;
+ }
+ void set_type_annotations(AnnotationArray* anno) {
+ *(type_annotations_addr()) = anno;
+ }
+
+ AnnotationArray** default_annotations_addr() const;
+ AnnotationArray* default_annotations() const {
+ return has_default_annotations() ? *(default_annotations_addr()) : NULL;
+ }
+ void set_default_annotations(AnnotationArray* anno) {
+ *(default_annotations_addr()) = anno;
+ }
+
+ int method_annotations_length() const {
+ return has_method_annotations() ? method_annotations()->length() : 0;
+ }
+ int parameter_annotations_length() const {
+ return has_parameter_annotations() ? parameter_annotations()->length() : 0;
+ }
+ int type_annotations_length() const {
+ return has_type_annotations() ? type_annotations()->length() : 0;
+ }
+ int default_annotations_length() const {
+ return has_default_annotations() ? default_annotations()->length() : 0;
+ }
+
+ // Copy annotations from other ConstMethod
+ void copy_annotations_from(ClassLoaderData* loader_data, ConstMethod* cm, TRAPS);
+
+ // byte codes
+ void set_code(address code) {
+ if (code_size() > 0) {
+ memcpy(code_base(), code, code_size());
+ }
+ }
+ address code_base() const { return (address) (this+1); }
+ address code_end() const { return code_base() + code_size(); }
+ bool contains(address bcp) const { return code_base() <= bcp
+ && bcp < code_end(); }
+ // Offset to bytecodes
+ static ByteSize codes_offset()
+ { return in_ByteSize(sizeof(ConstMethod)); }
+
+ static ByteSize constants_offset()
+ { return byte_offset_of(ConstMethod, _constants); }
+
+ static ByteSize max_stack_offset()
+ { return byte_offset_of(ConstMethod, _max_stack); }
+ static ByteSize size_of_locals_offset()
+ { return byte_offset_of(ConstMethod, _max_locals); }
+ static ByteSize size_of_parameters_offset()
+ { return byte_offset_of(ConstMethod, _size_of_parameters); }
+
+ static ByteSize result_type_offset()
+ { return byte_offset_of(ConstMethod, _result_type); }
+
+ // Unique id for the method
+ static const u2 MAX_IDNUM;
+ static const u2 UNSET_IDNUM;
+ u2 method_idnum() const { return _method_idnum; }
+ void set_method_idnum(u2 idnum) { _method_idnum = idnum; }
+
+ u2 orig_method_idnum() const { return _orig_method_idnum; }
+ void set_orig_method_idnum(u2 idnum) { _orig_method_idnum = idnum; }
+
+ // max stack
+ int max_stack() const { return _max_stack; }
+ void set_max_stack(int size) { _max_stack = size; }
+
+ // max locals
+ int max_locals() const { return _max_locals; }
+ void set_max_locals(int size) { _max_locals = size; }
+
+ // size of parameters
+ int size_of_parameters() const { return _size_of_parameters; }
+ void set_size_of_parameters(int size) { _size_of_parameters = size; }
+
+ void set_result_type(BasicType rt) { assert(rt < 16, "result type too large");
+ _result_type = (u1)rt; }
+ // Deallocation for RedefineClasses
+ void deallocate_contents(ClassLoaderData* loader_data);
+ bool is_klass() const { return false; }
+ DEBUG_ONLY(bool on_stack() { return false; })
+
+ void metaspace_pointers_do(MetaspaceClosure* it);
+ MetaspaceObj::Type type() const { return ConstMethodType; }
+private:
+ // Since the size of the compressed line number table is unknown, the
+ // offsets of the other variable sized sections are computed backwards
+ // from the end of the ConstMethod*.
+
+ // First byte after ConstMethod*
+ address constMethod_end() const
+ { return (address)((intptr_t*)this + _constMethod_size); }
+
+ // Last short in ConstMethod*
+ u2* last_u2_element() const;
+
+ public:
+ // Printing
+ void print_on (outputStream* st) const;
+ void print_value_on(outputStream* st) const;
+
+ const char* internal_name() const { return "{constMethod}"; }
+
+ // Verify
+ void verify_on(outputStream* st);
+};
+
+#endif // SHARE_VM_OOPS_CONSTMETHODOOP_HPP