--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/oops/constMethod.hpp Sat Sep 01 13:25:18 2012 -0400
@@ -0,0 +1,331 @@
+/*
+ * Copyright (c) 2003, 2012, 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"
+
+// An ConstMethod* represents portions of a Java method which
+// do not vary.
+//
+// Memory layout (each line represents a word). Note that most
+// applications load thousands of methods, so keeping the size of this
+// structure small has a big impact on footprint.
+//
+// |------------------------------------------------------|
+// | header |
+// | klass |
+// |------------------------------------------------------|
+// | fingerprint 1 |
+// | fingerprint 2 |
+// | constants (oop) |
+// | stackmap_data (oop) |
+// | constMethod_size |
+// | interp_kind | flags | code_size |
+// | name index | signature index |
+// | method_idnum | generic_signature_index |
+// |------------------------------------------------------|
+// | |
+// | byte codes |
+// | |
+// |------------------------------------------------------|
+// | 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!) |
+// |------------------------------------------------------|
+// | 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*) |
+// |------------------------------------------------------|
+// | 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*) |
+// |------------------------------------------------------|
+// | 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*) |
+// |------------------------------------------------------|
+
+
+// Utitily class decribing elements in checked exceptions table inlined in Method*.
+class CheckedExceptionElement VALUE_OBJ_CLASS_SPEC {
+ public:
+ u2 class_cp_index;
+};
+
+
+// Utitily class decribing 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;
+};
+
+// Utitily 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;
+};
+
+
+class ConstMethod : public MetaspaceObj {
+ friend class VMStructs;
+private:
+ enum {
+ _has_linenumber_table = 1,
+ _has_checked_exceptions = 2,
+ _has_localvariable_table = 4,
+ _has_exception_table = 8
+ };
+
+ // 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;
+
+ ConstantPool* _constants; // Constant pool
+
+ // Raw stackmap data for the method
+ Array<u1>* _stackmap_data;
+
+ int _constMethod_size;
+ jbyte _interpreter_kind;
+ jbyte _flags;
+
+ // 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 _generic_signature_index; // Generic signature (index in constant pool, 0 if absent)
+
+
+ // Constructor
+ ConstMethod(int byte_code_size,
+ int compressed_line_number_size,
+ int localvariable_table_length,
+ int exception_table_length,
+ int checked_exceptions_length,
+ int size);
+public:
+ static ConstMethod* allocate(ClassLoaderData* loader_data,
+ int byte_code_size,
+ int compressed_line_number_size,
+ int localvariable_table_length,
+ int exception_table_length,
+ int checked_exceptions_length,
+ TRAPS);
+
+ bool is_constMethod() const { return true; }
+
+ // Inlined tables
+ void set_inlined_tables_length(int checked_exceptions_len,
+ int compressed_line_number_size,
+ int localvariable_table_len,
+ int exception_table_len);
+
+ 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; }
+
+ void set_interpreter_kind(int kind) { _interpreter_kind = kind; }
+ int interpreter_kind(void) const { return _interpreter_kind; }
+
+ // 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; }
+ bool has_stackmap_table() const { return _stackmap_data != NULL; }
+
+ void init_fingerprint() {
+ const uint64_t initval = CONST64(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 { return _generic_signature_index; }
+ void set_generic_signature_index(int index) { _generic_signature_index = index; }
+
+ // Sizing
+ static int header_size() {
+ return sizeof(ConstMethod)/HeapWordSize;
+ }
+
+ // Size needed
+ static int size(int code_size, int compressed_line_number_size,
+ int local_variable_table_length,
+ int exception_table_length,
+ int checked_exceptions_length);
+
+ int size() const { return _constMethod_size;}
+ void set_constMethod_size(int size) { _constMethod_size = size; }
+
+ // 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* checked_exceptions_length_addr() const;
+ u2* localvariable_table_length_addr() const;
+ u2* exception_table_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;
+
+ // 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); }
+
+ // 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; }
+
+ // Deallocation for RedefineClasses
+ void deallocate_contents(ClassLoaderData* loader_data);
+ bool is_klass() const { return false; }
+ DEBUG_ONLY(bool on_stack() { return false; })
+
+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)((oop*)this + _constMethod_size); }
+
+ // Last short in ConstMethod*
+ u2* last_u2_element() const
+ { return (u2*)constMethod_end() - 1; }
+
+ 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