--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/oops/constantPool.hpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,1031 @@
+/*
+ * Copyright (c) 1997, 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_CONSTANTPOOLOOP_HPP
+#define SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP
+
+#include "oops/arrayOop.hpp"
+#include "oops/cpCache.hpp"
+#include "oops/objArrayOop.hpp"
+#include "oops/oopHandle.hpp"
+#include "oops/symbol.hpp"
+#include "oops/typeArrayOop.hpp"
+#include "runtime/handles.hpp"
+#include "utilities/align.hpp"
+#include "utilities/bytes.hpp"
+#include "utilities/constantTag.hpp"
+
+// A ConstantPool is an array containing class constants as described in the
+// class file.
+//
+// Most of the constant pool entries are written during class parsing, which
+// is safe. For klass types, the constant pool entry is
+// modified when the entry is resolved. If a klass constant pool
+// entry is read without a lock, only the resolved state guarantees that
+// the entry in the constant pool is a klass object and not a Symbol*.
+
+class SymbolHashMap;
+
+class CPSlot VALUE_OBJ_CLASS_SPEC {
+ friend class ConstantPool;
+ intptr_t _ptr;
+ enum TagBits {_pseudo_bit = 1};
+ public:
+
+ CPSlot(intptr_t ptr): _ptr(ptr) {}
+ CPSlot(Symbol* ptr, int tag_bits = 0): _ptr((intptr_t)ptr | tag_bits) {}
+
+ intptr_t value() { return _ptr; }
+ bool is_pseudo_string() { return (_ptr & _pseudo_bit) != 0; }
+
+ Symbol* get_symbol() {
+ return (Symbol*)(_ptr & ~_pseudo_bit);
+ }
+};
+
+// This represents a JVM_CONSTANT_Class, JVM_CONSTANT_UnresolvedClass, or
+// JVM_CONSTANT_UnresolvedClassInError slot in the constant pool.
+class CPKlassSlot VALUE_OBJ_CLASS_SPEC {
+ // cp->symbol_at(_name_index) gives the name of the class.
+ int _name_index;
+
+ // cp->_resolved_klasses->at(_resolved_klass_index) gives the Klass* for the class.
+ int _resolved_klass_index;
+public:
+ enum {
+ // This is used during constant pool merging where the resolved klass index is
+ // not yet known, and will be computed at a later stage (during a call to
+ // initialize_unresolved_klasses()).
+ _temp_resolved_klass_index = 0xffff
+ };
+ CPKlassSlot(int n, int rk) {
+ _name_index = n;
+ _resolved_klass_index = rk;
+ }
+ int name_index() const {
+ return _name_index;
+ }
+ int resolved_klass_index() const {
+ assert(_resolved_klass_index != _temp_resolved_klass_index, "constant pool merging was incomplete");
+ return _resolved_klass_index;
+ }
+};
+
+class KlassSizeStats;
+
+class ConstantPool : public Metadata {
+ friend class VMStructs;
+ friend class JVMCIVMStructs;
+ friend class BytecodeInterpreter; // Directly extracts a klass in the pool for fast instanceof/checkcast
+ friend class Universe; // For null constructor
+ private:
+ // If you add a new field that points to any metaspace object, you
+ // must add this field to ConstantPool::metaspace_pointers_do().
+ Array<u1>* _tags; // the tag array describing the constant pool's contents
+ ConstantPoolCache* _cache; // the cache holding interpreter runtime information
+ InstanceKlass* _pool_holder; // the corresponding class
+ Array<u2>* _operands; // for variable-sized (InvokeDynamic) nodes, usually empty
+
+ // Consider using an array of compressed klass pointers to
+ // save space on 64-bit platforms.
+ Array<Klass*>* _resolved_klasses;
+
+ enum {
+ _has_preresolution = 1, // Flags
+ _on_stack = 2,
+ _is_shared = 4
+ };
+
+ int _flags; // old fashioned bit twiddling
+ int _length; // number of elements in the array
+
+ union {
+ // set for CDS to restore resolved references
+ int _resolved_reference_length;
+ // keeps version number for redefined classes (used in backtrace)
+ int _version;
+ } _saved;
+
+ void set_tags(Array<u1>* tags) { _tags = tags; }
+ void tag_at_put(int which, jbyte t) { tags()->at_put(which, t); }
+ void release_tag_at_put(int which, jbyte t) { tags()->release_at_put(which, t); }
+
+ u1* tag_addr_at(int which) const { return tags()->adr_at(which); }
+
+ void set_operands(Array<u2>* operands) { _operands = operands; }
+
+ int flags() const { return _flags; }
+ void set_flags(int f) { _flags = f; }
+
+ private:
+ intptr_t* base() const { return (intptr_t*) (((char*) this) + sizeof(ConstantPool)); }
+
+ CPSlot slot_at(int which) const {
+ assert(is_within_bounds(which), "index out of bounds");
+ assert(!tag_at(which).is_unresolved_klass() && !tag_at(which).is_unresolved_klass_in_error(), "Corrupted constant pool");
+ // Uses volatile because the klass slot changes without a lock.
+ volatile intptr_t adr = (intptr_t)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which));
+ assert(adr != 0 || which == 0, "cp entry for klass should not be zero");
+ return CPSlot(adr);
+ }
+
+ void slot_at_put(int which, CPSlot s) const {
+ assert(is_within_bounds(which), "index out of bounds");
+ assert(s.value() != 0, "Caught something");
+ *(intptr_t*)&base()[which] = s.value();
+ }
+ intptr_t* obj_at_addr_raw(int which) const {
+ assert(is_within_bounds(which), "index out of bounds");
+ return (intptr_t*) &base()[which];
+ }
+
+ jint* int_at_addr(int which) const {
+ assert(is_within_bounds(which), "index out of bounds");
+ return (jint*) &base()[which];
+ }
+
+ jlong* long_at_addr(int which) const {
+ assert(is_within_bounds(which), "index out of bounds");
+ return (jlong*) &base()[which];
+ }
+
+ jfloat* float_at_addr(int which) const {
+ assert(is_within_bounds(which), "index out of bounds");
+ return (jfloat*) &base()[which];
+ }
+
+ jdouble* double_at_addr(int which) const {
+ assert(is_within_bounds(which), "index out of bounds");
+ return (jdouble*) &base()[which];
+ }
+
+ ConstantPool(Array<u1>* tags);
+ ConstantPool() { assert(DumpSharedSpaces || UseSharedSpaces, "only for CDS"); }
+ public:
+ static ConstantPool* allocate(ClassLoaderData* loader_data, int length, TRAPS);
+
+ bool is_constantPool() const volatile { return true; }
+
+ Array<u1>* tags() const { return _tags; }
+ Array<u2>* operands() const { return _operands; }
+
+ bool has_preresolution() const { return (_flags & _has_preresolution) != 0; }
+ void set_has_preresolution() {
+ assert(!is_shared(), "should never be called on shared ConstantPools");
+ _flags |= _has_preresolution;
+ }
+
+ // Redefine classes support. If a method refering to this constant pool
+ // is on the executing stack, or as a handle in vm code, this constant pool
+ // can't be removed from the set of previous versions saved in the instance
+ // class.
+ bool on_stack() const { return (_flags &_on_stack) != 0; }
+ void set_on_stack(const bool value);
+
+ // Faster than MetaspaceObj::is_shared() - used by set_on_stack()
+ bool is_shared() const { return (_flags & _is_shared) != 0; }
+
+ // Klass holding pool
+ InstanceKlass* pool_holder() const { return _pool_holder; }
+ void set_pool_holder(InstanceKlass* k) { _pool_holder = k; }
+ InstanceKlass** pool_holder_addr() { return &_pool_holder; }
+
+ // Interpreter runtime support
+ ConstantPoolCache* cache() const { return _cache; }
+ void set_cache(ConstantPoolCache* cache){ _cache = cache; }
+
+ virtual void metaspace_pointers_do(MetaspaceClosure* iter);
+ virtual MetaspaceObj::Type type() const { return ConstantPoolType; }
+
+ // Create object cache in the constant pool
+ void initialize_resolved_references(ClassLoaderData* loader_data,
+ const intStack& reference_map,
+ int constant_pool_map_length,
+ TRAPS);
+
+ // resolved strings, methodHandles and callsite objects from the constant pool
+ objArrayOop resolved_references() const;
+ // mapping resolved object array indexes to cp indexes and back.
+ int object_to_cp_index(int index) { return reference_map()->at(index); }
+ int cp_to_object_index(int index);
+
+ void set_resolved_klasses(Array<Klass*>* rk) { _resolved_klasses = rk; }
+ Array<Klass*>* resolved_klasses() const { return _resolved_klasses; }
+ void allocate_resolved_klasses(ClassLoaderData* loader_data, int num_klasses, TRAPS);
+ void initialize_unresolved_klasses(ClassLoaderData* loader_data, TRAPS);
+
+ // Invokedynamic indexes.
+ // They must look completely different from normal indexes.
+ // The main reason is that byte swapping is sometimes done on normal indexes.
+ // Finally, it is helpful for debugging to tell the two apart.
+ static bool is_invokedynamic_index(int i) { return (i < 0); }
+ static int decode_invokedynamic_index(int i) { assert(is_invokedynamic_index(i), ""); return ~i; }
+ static int encode_invokedynamic_index(int i) { assert(!is_invokedynamic_index(i), ""); return ~i; }
+
+
+ // The invokedynamic points at a CP cache entry. This entry points back
+ // at the original CP entry (CONSTANT_InvokeDynamic) and also (via f2) at an entry
+ // in the resolved_references array (which provides the appendix argument).
+ int invokedynamic_cp_cache_index(int index) const {
+ assert (is_invokedynamic_index(index), "should be a invokedynamic index");
+ int cache_index = decode_invokedynamic_index(index);
+ return cache_index;
+ }
+ ConstantPoolCacheEntry* invokedynamic_cp_cache_entry_at(int index) const {
+ // decode index that invokedynamic points to.
+ int cp_cache_index = invokedynamic_cp_cache_index(index);
+ return cache()->entry_at(cp_cache_index);
+ }
+
+ // Assembly code support
+ static int tags_offset_in_bytes() { return offset_of(ConstantPool, _tags); }
+ static int cache_offset_in_bytes() { return offset_of(ConstantPool, _cache); }
+ static int pool_holder_offset_in_bytes() { return offset_of(ConstantPool, _pool_holder); }
+ static int resolved_klasses_offset_in_bytes() { return offset_of(ConstantPool, _resolved_klasses); }
+
+ // Storing constants
+
+ // For temporary use while constructing constant pool
+ void klass_index_at_put(int which, int name_index) {
+ tag_at_put(which, JVM_CONSTANT_ClassIndex);
+ *int_at_addr(which) = name_index;
+ }
+
+ // Anonymous class support:
+ void klass_at_put(int class_index, int name_index, int resolved_klass_index, Klass* k, Symbol* name);
+ void klass_at_put(int class_index, Klass* k);
+
+ void unresolved_klass_at_put(int which, int name_index, int resolved_klass_index) {
+ release_tag_at_put(which, JVM_CONSTANT_UnresolvedClass);
+
+ assert((name_index & 0xffff0000) == 0, "must be");
+ assert((resolved_klass_index & 0xffff0000) == 0, "must be");
+ *int_at_addr(which) =
+ build_int_from_shorts((jushort)resolved_klass_index, (jushort)name_index);
+ }
+
+ void method_handle_index_at_put(int which, int ref_kind, int ref_index) {
+ tag_at_put(which, JVM_CONSTANT_MethodHandle);
+ *int_at_addr(which) = ((jint) ref_index<<16) | ref_kind;
+ }
+
+ void method_type_index_at_put(int which, int ref_index) {
+ tag_at_put(which, JVM_CONSTANT_MethodType);
+ *int_at_addr(which) = ref_index;
+ }
+
+ void invoke_dynamic_at_put(int which, int bootstrap_specifier_index, int name_and_type_index) {
+ tag_at_put(which, JVM_CONSTANT_InvokeDynamic);
+ *int_at_addr(which) = ((jint) name_and_type_index<<16) | bootstrap_specifier_index;
+ }
+
+ void unresolved_string_at_put(int which, Symbol* s) {
+ release_tag_at_put(which, JVM_CONSTANT_String);
+ slot_at_put(which, CPSlot(s));
+ }
+
+ void int_at_put(int which, jint i) {
+ tag_at_put(which, JVM_CONSTANT_Integer);
+ *int_at_addr(which) = i;
+ }
+
+ void long_at_put(int which, jlong l) {
+ tag_at_put(which, JVM_CONSTANT_Long);
+ // *long_at_addr(which) = l;
+ Bytes::put_native_u8((address)long_at_addr(which), *((u8*) &l));
+ }
+
+ void float_at_put(int which, jfloat f) {
+ tag_at_put(which, JVM_CONSTANT_Float);
+ *float_at_addr(which) = f;
+ }
+
+ void double_at_put(int which, jdouble d) {
+ tag_at_put(which, JVM_CONSTANT_Double);
+ // *double_at_addr(which) = d;
+ // u8 temp = *(u8*) &d;
+ Bytes::put_native_u8((address) double_at_addr(which), *((u8*) &d));
+ }
+
+ Symbol** symbol_at_addr(int which) const {
+ assert(is_within_bounds(which), "index out of bounds");
+ return (Symbol**) &base()[which];
+ }
+
+ void symbol_at_put(int which, Symbol* s) {
+ assert(s->refcount() != 0, "should have nonzero refcount");
+ tag_at_put(which, JVM_CONSTANT_Utf8);
+ *symbol_at_addr(which) = s;
+ }
+
+ void string_at_put(int which, int obj_index, oop str);
+
+ // For temporary use while constructing constant pool
+ void string_index_at_put(int which, int string_index) {
+ tag_at_put(which, JVM_CONSTANT_StringIndex);
+ *int_at_addr(which) = string_index;
+ }
+
+ void field_at_put(int which, int class_index, int name_and_type_index) {
+ tag_at_put(which, JVM_CONSTANT_Fieldref);
+ *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index;
+ }
+
+ void method_at_put(int which, int class_index, int name_and_type_index) {
+ tag_at_put(which, JVM_CONSTANT_Methodref);
+ *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index;
+ }
+
+ void interface_method_at_put(int which, int class_index, int name_and_type_index) {
+ tag_at_put(which, JVM_CONSTANT_InterfaceMethodref);
+ *int_at_addr(which) = ((jint) name_and_type_index<<16) | class_index; // Not so nice
+ }
+
+ void name_and_type_at_put(int which, int name_index, int signature_index) {
+ tag_at_put(which, JVM_CONSTANT_NameAndType);
+ *int_at_addr(which) = ((jint) signature_index<<16) | name_index; // Not so nice
+ }
+
+ // Tag query
+
+ constantTag tag_at(int which) const { return (constantTag)tags()->at_acquire(which); }
+
+ // Fetching constants
+
+ Klass* klass_at(int which, TRAPS) {
+ constantPoolHandle h_this(THREAD, this);
+ return klass_at_impl(h_this, which, true, THREAD);
+ }
+
+ // Version of klass_at that doesn't save the resolution error, called during deopt
+ Klass* klass_at_ignore_error(int which, TRAPS) {
+ constantPoolHandle h_this(THREAD, this);
+ return klass_at_impl(h_this, which, false, THREAD);
+ }
+
+ CPKlassSlot klass_slot_at(int which) const {
+ assert(tag_at(which).is_unresolved_klass() || tag_at(which).is_klass(),
+ "Corrupted constant pool");
+ int value = *int_at_addr(which);
+ int name_index = extract_high_short_from_int(value);
+ int resolved_klass_index = extract_low_short_from_int(value);
+ return CPKlassSlot(name_index, resolved_klass_index);
+ }
+
+ Symbol* klass_name_at(int which) const; // Returns the name, w/o resolving.
+ int klass_name_index_at(int which) const {
+ return klass_slot_at(which).name_index();
+ }
+
+ Klass* resolved_klass_at(int which) const { // Used by Compiler
+ guarantee(tag_at(which).is_klass(), "Corrupted constant pool");
+ // Must do an acquire here in case another thread resolved the klass
+ // behind our back, lest we later load stale values thru the oop.
+ CPKlassSlot kslot = klass_slot_at(which);
+ assert(tag_at(kslot.name_index()).is_symbol(), "sanity");
+
+ Klass** adr = resolved_klasses()->adr_at(kslot.resolved_klass_index());
+ return (Klass*)OrderAccess::load_ptr_acquire(adr);
+ }
+
+ // RedefineClasses() API support:
+ Symbol* klass_at_noresolve(int which) { return klass_name_at(which); }
+ void temp_unresolved_klass_at_put(int which, int name_index) {
+ // Used only during constant pool merging for class redefinition. The resolved klass index
+ // will be initialized later by a call to initialize_unresolved_klasses().
+ unresolved_klass_at_put(which, name_index, CPKlassSlot::_temp_resolved_klass_index);
+ }
+
+ jint int_at(int which) {
+ assert(tag_at(which).is_int(), "Corrupted constant pool");
+ return *int_at_addr(which);
+ }
+
+ jlong long_at(int which) {
+ assert(tag_at(which).is_long(), "Corrupted constant pool");
+ // return *long_at_addr(which);
+ u8 tmp = Bytes::get_native_u8((address)&base()[which]);
+ return *((jlong*)&tmp);
+ }
+
+ jfloat float_at(int which) {
+ assert(tag_at(which).is_float(), "Corrupted constant pool");
+ return *float_at_addr(which);
+ }
+
+ jdouble double_at(int which) {
+ assert(tag_at(which).is_double(), "Corrupted constant pool");
+ u8 tmp = Bytes::get_native_u8((address)&base()[which]);
+ return *((jdouble*)&tmp);
+ }
+
+ Symbol* symbol_at(int which) const {
+ assert(tag_at(which).is_utf8(), "Corrupted constant pool");
+ return *symbol_at_addr(which);
+ }
+
+ oop string_at(int which, int obj_index, TRAPS) {
+ constantPoolHandle h_this(THREAD, this);
+ return string_at_impl(h_this, which, obj_index, THREAD);
+ }
+ oop string_at(int which, TRAPS) {
+ int obj_index = cp_to_object_index(which);
+ return string_at(which, obj_index, THREAD);
+ }
+
+ // Version that can be used before string oop array is created.
+ oop uncached_string_at(int which, TRAPS);
+
+ // A "pseudo-string" is an non-string oop that has found its way into
+ // a String entry.
+ // This can happen if the user patches a live
+ // object into a CONSTANT_String entry of an anonymous class.
+ // Method oops internally created for method handles may also
+ // use pseudo-strings to link themselves to related metaobjects.
+
+ bool is_pseudo_string_at(int which) {
+ assert(tag_at(which).is_string(), "Corrupted constant pool");
+ return slot_at(which).is_pseudo_string();
+ }
+
+ oop pseudo_string_at(int which, int obj_index) {
+ assert(is_pseudo_string_at(which), "must be a pseudo-string");
+ oop s = resolved_references()->obj_at(obj_index);
+ return s;
+ }
+
+ oop pseudo_string_at(int which) {
+ assert(is_pseudo_string_at(which), "must be a pseudo-string");
+ int obj_index = cp_to_object_index(which);
+ oop s = resolved_references()->obj_at(obj_index);
+ return s;
+ }
+
+ void pseudo_string_at_put(int which, int obj_index, oop x) {
+ assert(tag_at(which).is_string(), "Corrupted constant pool");
+ Symbol* sym = unresolved_string_at(which);
+ slot_at_put(which, CPSlot(sym, CPSlot::_pseudo_bit));
+ string_at_put(which, obj_index, x); // this works just fine
+ }
+
+ // only called when we are sure a string entry is already resolved (via an
+ // earlier string_at call.
+ oop resolved_string_at(int which) {
+ assert(tag_at(which).is_string(), "Corrupted constant pool");
+ // Must do an acquire here in case another thread resolved the klass
+ // behind our back, lest we later load stale values thru the oop.
+ // we might want a volatile_obj_at in ObjArrayKlass.
+ int obj_index = cp_to_object_index(which);
+ return resolved_references()->obj_at(obj_index);
+ }
+
+ Symbol* unresolved_string_at(int which) {
+ assert(tag_at(which).is_string(), "Corrupted constant pool");
+ Symbol* sym = slot_at(which).get_symbol();
+ return sym;
+ }
+
+ // Returns an UTF8 for a CONSTANT_String entry at a given index.
+ // UTF8 char* representation was chosen to avoid conversion of
+ // java_lang_Strings at resolved entries into Symbol*s
+ // or vice versa.
+ char* string_at_noresolve(int which);
+
+ jint name_and_type_at(int which) {
+ assert(tag_at(which).is_name_and_type(), "Corrupted constant pool");
+ return *int_at_addr(which);
+ }
+
+ int method_handle_ref_kind_at(int which) {
+ assert(tag_at(which).is_method_handle() ||
+ tag_at(which).is_method_handle_in_error(), "Corrupted constant pool");
+ return extract_low_short_from_int(*int_at_addr(which)); // mask out unwanted ref_index bits
+ }
+ int method_handle_index_at(int which) {
+ assert(tag_at(which).is_method_handle() ||
+ tag_at(which).is_method_handle_in_error(), "Corrupted constant pool");
+ return extract_high_short_from_int(*int_at_addr(which)); // shift out unwanted ref_kind bits
+ }
+ int method_type_index_at(int which) {
+ assert(tag_at(which).is_method_type() ||
+ tag_at(which).is_method_type_in_error(), "Corrupted constant pool");
+ return *int_at_addr(which);
+ }
+
+ // Derived queries:
+ Symbol* method_handle_name_ref_at(int which) {
+ int member = method_handle_index_at(which);
+ return impl_name_ref_at(member, true);
+ }
+ Symbol* method_handle_signature_ref_at(int which) {
+ int member = method_handle_index_at(which);
+ return impl_signature_ref_at(member, true);
+ }
+ int method_handle_klass_index_at(int which) {
+ int member = method_handle_index_at(which);
+ return impl_klass_ref_index_at(member, true);
+ }
+ Symbol* method_type_signature_at(int which) {
+ int sym = method_type_index_at(which);
+ return symbol_at(sym);
+ }
+
+ int invoke_dynamic_name_and_type_ref_index_at(int which) {
+ assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool");
+ return extract_high_short_from_int(*int_at_addr(which));
+ }
+ int invoke_dynamic_bootstrap_specifier_index(int which) {
+ assert(tag_at(which).value() == JVM_CONSTANT_InvokeDynamic, "Corrupted constant pool");
+ return extract_low_short_from_int(*int_at_addr(which));
+ }
+ int invoke_dynamic_operand_base(int which) {
+ int bootstrap_specifier_index = invoke_dynamic_bootstrap_specifier_index(which);
+ return operand_offset_at(operands(), bootstrap_specifier_index);
+ }
+ // The first part of the operands array consists of an index into the second part.
+ // Extract a 32-bit index value from the first part.
+ static int operand_offset_at(Array<u2>* operands, int bootstrap_specifier_index) {
+ int n = (bootstrap_specifier_index * 2);
+ assert(n >= 0 && n+2 <= operands->length(), "oob");
+ // The first 32-bit index points to the beginning of the second part
+ // of the operands array. Make sure this index is in the first part.
+ DEBUG_ONLY(int second_part = build_int_from_shorts(operands->at(0),
+ operands->at(1)));
+ assert(second_part == 0 || n+2 <= second_part, "oob (2)");
+ int offset = build_int_from_shorts(operands->at(n+0),
+ operands->at(n+1));
+ // The offset itself must point into the second part of the array.
+ assert(offset == 0 || offset >= second_part && offset <= operands->length(), "oob (3)");
+ return offset;
+ }
+ static void operand_offset_at_put(Array<u2>* operands, int bootstrap_specifier_index, int offset) {
+ int n = bootstrap_specifier_index * 2;
+ assert(n >= 0 && n+2 <= operands->length(), "oob");
+ operands->at_put(n+0, extract_low_short_from_int(offset));
+ operands->at_put(n+1, extract_high_short_from_int(offset));
+ }
+ static int operand_array_length(Array<u2>* operands) {
+ if (operands == NULL || operands->length() == 0) return 0;
+ int second_part = operand_offset_at(operands, 0);
+ return (second_part / 2);
+ }
+
+#ifdef ASSERT
+ // operand tuples fit together exactly, end to end
+ static int operand_limit_at(Array<u2>* operands, int bootstrap_specifier_index) {
+ int nextidx = bootstrap_specifier_index + 1;
+ if (nextidx == operand_array_length(operands))
+ return operands->length();
+ else
+ return operand_offset_at(operands, nextidx);
+ }
+ int invoke_dynamic_operand_limit(int which) {
+ int bootstrap_specifier_index = invoke_dynamic_bootstrap_specifier_index(which);
+ return operand_limit_at(operands(), bootstrap_specifier_index);
+ }
+#endif //ASSERT
+
+ // layout of InvokeDynamic bootstrap method specifier (in second part of operands array):
+ enum {
+ _indy_bsm_offset = 0, // CONSTANT_MethodHandle bsm
+ _indy_argc_offset = 1, // u2 argc
+ _indy_argv_offset = 2 // u2 argv[argc]
+ };
+
+ // These functions are used in RedefineClasses for CP merge
+
+ int operand_offset_at(int bootstrap_specifier_index) {
+ assert(0 <= bootstrap_specifier_index &&
+ bootstrap_specifier_index < operand_array_length(operands()),
+ "Corrupted CP operands");
+ return operand_offset_at(operands(), bootstrap_specifier_index);
+ }
+ int operand_bootstrap_method_ref_index_at(int bootstrap_specifier_index) {
+ int offset = operand_offset_at(bootstrap_specifier_index);
+ return operands()->at(offset + _indy_bsm_offset);
+ }
+ int operand_argument_count_at(int bootstrap_specifier_index) {
+ int offset = operand_offset_at(bootstrap_specifier_index);
+ int argc = operands()->at(offset + _indy_argc_offset);
+ return argc;
+ }
+ int operand_argument_index_at(int bootstrap_specifier_index, int j) {
+ int offset = operand_offset_at(bootstrap_specifier_index);
+ return operands()->at(offset + _indy_argv_offset + j);
+ }
+ int operand_next_offset_at(int bootstrap_specifier_index) {
+ int offset = operand_offset_at(bootstrap_specifier_index) + _indy_argv_offset
+ + operand_argument_count_at(bootstrap_specifier_index);
+ return offset;
+ }
+ // Compare a bootsrap specifier in the operands arrays
+ bool compare_operand_to(int bootstrap_specifier_index1, const constantPoolHandle& cp2,
+ int bootstrap_specifier_index2, TRAPS);
+ // Find a bootsrap specifier in the operands array
+ int find_matching_operand(int bootstrap_specifier_index, const constantPoolHandle& search_cp,
+ int operands_cur_len, TRAPS);
+ // Resize the operands array with delta_len and delta_size
+ void resize_operands(int delta_len, int delta_size, TRAPS);
+ // Extend the operands array with the length and size of the ext_cp operands
+ void extend_operands(const constantPoolHandle& ext_cp, TRAPS);
+ // Shrink the operands array to a smaller array with new_len length
+ void shrink_operands(int new_len, TRAPS);
+
+
+ int invoke_dynamic_bootstrap_method_ref_index_at(int which) {
+ assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool");
+ int op_base = invoke_dynamic_operand_base(which);
+ return operands()->at(op_base + _indy_bsm_offset);
+ }
+ int invoke_dynamic_argument_count_at(int which) {
+ assert(tag_at(which).is_invoke_dynamic(), "Corrupted constant pool");
+ int op_base = invoke_dynamic_operand_base(which);
+ int argc = operands()->at(op_base + _indy_argc_offset);
+ DEBUG_ONLY(int end_offset = op_base + _indy_argv_offset + argc;
+ int next_offset = invoke_dynamic_operand_limit(which));
+ assert(end_offset == next_offset, "matched ending");
+ return argc;
+ }
+ int invoke_dynamic_argument_index_at(int which, int j) {
+ int op_base = invoke_dynamic_operand_base(which);
+ DEBUG_ONLY(int argc = operands()->at(op_base + _indy_argc_offset));
+ assert((uint)j < (uint)argc, "oob");
+ return operands()->at(op_base + _indy_argv_offset + j);
+ }
+
+ // The following methods (name/signature/klass_ref_at, klass_ref_at_noresolve,
+ // name_and_type_ref_index_at) all expect to be passed indices obtained
+ // directly from the bytecode.
+ // If the indices are meant to refer to fields or methods, they are
+ // actually rewritten constant pool cache indices.
+ // The routine remap_instruction_operand_from_cache manages the adjustment
+ // of these values back to constant pool indices.
+
+ // There are also "uncached" versions which do not adjust the operand index; see below.
+
+ // FIXME: Consider renaming these with a prefix "cached_" to make the distinction clear.
+ // In a few cases (the verifier) there are uses before a cpcache has been built,
+ // which are handled by a dynamic check in remap_instruction_operand_from_cache.
+ // FIXME: Remove the dynamic check, and adjust all callers to specify the correct mode.
+
+ // Lookup for entries consisting of (klass_index, name_and_type index)
+ Klass* klass_ref_at(int which, TRAPS);
+ Symbol* klass_ref_at_noresolve(int which);
+ Symbol* name_ref_at(int which) { return impl_name_ref_at(which, false); }
+ Symbol* signature_ref_at(int which) { return impl_signature_ref_at(which, false); }
+
+ int klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, false); }
+ int name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, false); }
+
+ int remap_instruction_operand_from_cache(int operand); // operand must be biased by CPCACHE_INDEX_TAG
+
+ constantTag tag_ref_at(int cp_cache_index) { return impl_tag_ref_at(cp_cache_index, false); }
+
+ // Lookup for entries consisting of (name_index, signature_index)
+ int name_ref_index_at(int which_nt); // == low-order jshort of name_and_type_at(which_nt)
+ int signature_ref_index_at(int which_nt); // == high-order jshort of name_and_type_at(which_nt)
+
+ BasicType basic_type_for_signature_at(int which) const;
+
+ // Resolve string constants (to prevent allocation during compilation)
+ void resolve_string_constants(TRAPS) {
+ constantPoolHandle h_this(THREAD, this);
+ resolve_string_constants_impl(h_this, CHECK);
+ }
+
+ // CDS support
+ void archive_resolved_references(Thread *THREAD) NOT_CDS_JAVA_HEAP_RETURN;
+ void remove_unshareable_info();
+ void restore_unshareable_info(TRAPS);
+ bool resolve_class_constants(TRAPS);
+ // The ConstantPool vtable is restored by this call when the ConstantPool is
+ // in the shared archive. See patch_klass_vtables() in metaspaceShared.cpp for
+ // all the gory details. SA, dtrace and pstack helpers distinguish metadata
+ // by their vtable.
+ void restore_vtable() { guarantee(is_constantPool(), "vtable restored by this call"); }
+
+ private:
+ enum { _no_index_sentinel = -1, _possible_index_sentinel = -2 };
+ public:
+
+ // Resolve late bound constants.
+ oop resolve_constant_at(int index, TRAPS) {
+ constantPoolHandle h_this(THREAD, this);
+ return resolve_constant_at_impl(h_this, index, _no_index_sentinel, THREAD);
+ }
+
+ oop resolve_cached_constant_at(int cache_index, TRAPS) {
+ constantPoolHandle h_this(THREAD, this);
+ return resolve_constant_at_impl(h_this, _no_index_sentinel, cache_index, THREAD);
+ }
+
+ oop resolve_possibly_cached_constant_at(int pool_index, TRAPS) {
+ constantPoolHandle h_this(THREAD, this);
+ return resolve_constant_at_impl(h_this, pool_index, _possible_index_sentinel, THREAD);
+ }
+
+ oop resolve_bootstrap_specifier_at(int index, TRAPS) {
+ constantPoolHandle h_this(THREAD, this);
+ return resolve_bootstrap_specifier_at_impl(h_this, index, THREAD);
+ }
+
+ // Klass name matches name at offset
+ bool klass_name_at_matches(const InstanceKlass* k, int which);
+
+ // Sizing
+ int length() const { return _length; }
+ void set_length(int length) { _length = length; }
+
+ // Tells whether index is within bounds.
+ bool is_within_bounds(int index) const {
+ return 0 <= index && index < length();
+ }
+
+ // Sizing (in words)
+ static int header_size() {
+ return align_up((int)sizeof(ConstantPool), wordSize) / wordSize;
+ }
+ static int size(int length) { return align_metadata_size(header_size() + length); }
+ int size() const { return size(length()); }
+#if INCLUDE_SERVICES
+ void collect_statistics(KlassSizeStats *sz) const;
+#endif
+
+ // ConstantPools should be stored in the read-only region of CDS archive.
+ static bool is_read_only_by_default() { return true; }
+
+ friend class ClassFileParser;
+ friend class SystemDictionary;
+
+ // Used by CDS. These classes need to access the private ConstantPool() constructor.
+ template <class T> friend class CppVtableTesterA;
+ template <class T> friend class CppVtableTesterB;
+ template <class T> friend class CppVtableCloner;
+
+ // Used by compiler to prevent classloading.
+ static Method* method_at_if_loaded (const constantPoolHandle& this_cp, int which);
+ static bool has_appendix_at_if_loaded (const constantPoolHandle& this_cp, int which);
+ static oop appendix_at_if_loaded (const constantPoolHandle& this_cp, int which);
+ static bool has_method_type_at_if_loaded (const constantPoolHandle& this_cp, int which);
+ static oop method_type_at_if_loaded (const constantPoolHandle& this_cp, int which);
+ static Klass* klass_at_if_loaded (const constantPoolHandle& this_cp, int which);
+ static Klass* klass_ref_at_if_loaded (const constantPoolHandle& this_cp, int which);
+
+ // Routines currently used for annotations (only called by jvm.cpp) but which might be used in the
+ // future by other Java code. These take constant pool indices rather than
+ // constant pool cache indices as do the peer methods above.
+ Symbol* uncached_klass_ref_at_noresolve(int which);
+ Symbol* uncached_name_ref_at(int which) { return impl_name_ref_at(which, true); }
+ Symbol* uncached_signature_ref_at(int which) { return impl_signature_ref_at(which, true); }
+ int uncached_klass_ref_index_at(int which) { return impl_klass_ref_index_at(which, true); }
+ int uncached_name_and_type_ref_index_at(int which) { return impl_name_and_type_ref_index_at(which, true); }
+
+ // Sharing
+ int pre_resolve_shared_klasses(TRAPS);
+
+ // Debugging
+ const char* printable_name_at(int which) PRODUCT_RETURN0;
+
+#ifdef ASSERT
+ enum { CPCACHE_INDEX_TAG = 0x10000 }; // helps keep CP cache indices distinct from CP indices
+#else
+ enum { CPCACHE_INDEX_TAG = 0 }; // in product mode, this zero value is a no-op
+#endif //ASSERT
+
+ static int decode_cpcache_index(int raw_index, bool invokedynamic_ok = false) {
+ if (invokedynamic_ok && is_invokedynamic_index(raw_index))
+ return decode_invokedynamic_index(raw_index);
+ else
+ return raw_index - CPCACHE_INDEX_TAG;
+ }
+
+ private:
+
+ void set_resolved_references(OopHandle s) { _cache->set_resolved_references(s); }
+ Array<u2>* reference_map() const { return (_cache == NULL) ? NULL : _cache->reference_map(); }
+ void set_reference_map(Array<u2>* o) { _cache->set_reference_map(o); }
+
+ // patch JSR 292 resolved references after the class is linked.
+ void patch_resolved_references(GrowableArray<Handle>* cp_patches);
+
+ Symbol* impl_name_ref_at(int which, bool uncached);
+ Symbol* impl_signature_ref_at(int which, bool uncached);
+ int impl_klass_ref_index_at(int which, bool uncached);
+ int impl_name_and_type_ref_index_at(int which, bool uncached);
+ constantTag impl_tag_ref_at(int which, bool uncached);
+
+ // Used while constructing constant pool (only by ClassFileParser)
+ jint klass_index_at(int which) {
+ assert(tag_at(which).is_klass_index(), "Corrupted constant pool");
+ return *int_at_addr(which);
+ }
+
+ jint string_index_at(int which) {
+ assert(tag_at(which).is_string_index(), "Corrupted constant pool");
+ return *int_at_addr(which);
+ }
+
+ // Performs the LinkResolver checks
+ static void verify_constant_pool_resolve(const constantPoolHandle& this_cp, Klass* klass, TRAPS);
+
+ // Implementation of methods that needs an exposed 'this' pointer, in order to
+ // handle GC while executing the method
+ static Klass* klass_at_impl(const constantPoolHandle& this_cp, int which,
+ bool save_resolution_error, TRAPS);
+ static oop string_at_impl(const constantPoolHandle& this_cp, int which, int obj_index, TRAPS);
+
+ static void trace_class_resolution(const constantPoolHandle& this_cp, Klass* k);
+
+ // Resolve string constants (to prevent allocation during compilation)
+ static void resolve_string_constants_impl(const constantPoolHandle& this_cp, TRAPS);
+
+ static oop resolve_constant_at_impl(const constantPoolHandle& this_cp, int index, int cache_index, TRAPS);
+ static oop resolve_bootstrap_specifier_at_impl(const constantPoolHandle& this_cp, int index, TRAPS);
+
+ // Exception handling
+ static void throw_resolution_error(const constantPoolHandle& this_cp, int which, TRAPS);
+ static Symbol* exception_message(const constantPoolHandle& this_cp, int which, constantTag tag, oop pending_exception);
+ static void save_and_throw_exception(const constantPoolHandle& this_cp, int which, constantTag tag, TRAPS);
+
+ public:
+ // Merging ConstantPool* support:
+ bool compare_entry_to(int index1, const constantPoolHandle& cp2, int index2, TRAPS);
+ void copy_cp_to(int start_i, int end_i, const constantPoolHandle& to_cp, int to_i, TRAPS) {
+ constantPoolHandle h_this(THREAD, this);
+ copy_cp_to_impl(h_this, start_i, end_i, to_cp, to_i, THREAD);
+ }
+ static void copy_cp_to_impl(const constantPoolHandle& from_cp, int start_i, int end_i, const constantPoolHandle& to_cp, int to_i, TRAPS);
+ static void copy_entry_to(const constantPoolHandle& from_cp, int from_i, const constantPoolHandle& to_cp, int to_i, TRAPS);
+ static void copy_operands(const constantPoolHandle& from_cp, const constantPoolHandle& to_cp, TRAPS);
+ int find_matching_entry(int pattern_i, const constantPoolHandle& search_cp, TRAPS);
+ int version() const { return _saved._version; }
+ void set_version(int version) { _saved._version = version; }
+ void increment_and_save_version(int version) {
+ _saved._version = version >= 0 ? (version + 1) : version; // keep overflow
+ }
+
+ void set_resolved_reference_length(int length) { _saved._resolved_reference_length = length; }
+ int resolved_reference_length() const { return _saved._resolved_reference_length; }
+
+ // Decrease ref counts of symbols that are in the constant pool
+ // when the holder class is unloaded
+ void unreference_symbols();
+
+ // Deallocate constant pool for RedefineClasses
+ void deallocate_contents(ClassLoaderData* loader_data);
+ void release_C_heap_structures();
+
+ // JVMTI accesss - GetConstantPool, RetransformClasses, ...
+ friend class JvmtiConstantPoolReconstituter;
+
+ private:
+ jint cpool_entry_size(jint idx);
+ jint hash_entries_to(SymbolHashMap *symmap, SymbolHashMap *classmap);
+
+ // Copy cpool bytes into byte array.
+ // Returns:
+ // int > 0, count of the raw cpool bytes that have been copied
+ // 0, OutOfMemory error
+ // -1, Internal error
+ int copy_cpool_bytes(int cpool_size,
+ SymbolHashMap* tbl,
+ unsigned char *bytes);
+
+ public:
+ // Verify
+ void verify_on(outputStream* st);
+
+ // Printing
+ void print_on(outputStream* st) const;
+ void print_value_on(outputStream* st) const;
+ void print_entry_on(int index, outputStream* st);
+
+ const char* internal_name() const { return "{constant pool}"; }
+
+#ifndef PRODUCT
+ // Compile the world support
+ static void preload_and_initialize_all_classes(ConstantPool* constant_pool, TRAPS);
+#endif
+};
+
+class SymbolHashMapEntry : public CHeapObj<mtSymbol> {
+ private:
+ unsigned int _hash; // 32-bit hash for item
+ SymbolHashMapEntry* _next; // Next element in the linked list for this bucket
+ Symbol* _symbol; // 1-st part of the mapping: symbol => value
+ u2 _value; // 2-nd part of the mapping: symbol => value
+
+ public:
+ unsigned int hash() const { return _hash; }
+ void set_hash(unsigned int hash) { _hash = hash; }
+
+ SymbolHashMapEntry* next() const { return _next; }
+ void set_next(SymbolHashMapEntry* next) { _next = next; }
+
+ Symbol* symbol() const { return _symbol; }
+ void set_symbol(Symbol* sym) { _symbol = sym; }
+
+ u2 value() const { return _value; }
+ void set_value(u2 value) { _value = value; }
+
+ SymbolHashMapEntry(unsigned int hash, Symbol* symbol, u2 value)
+ : _hash(hash), _symbol(symbol), _value(value), _next(NULL) {}
+
+}; // End SymbolHashMapEntry class
+
+
+class SymbolHashMapBucket : public CHeapObj<mtSymbol> {
+
+private:
+ SymbolHashMapEntry* _entry;
+
+public:
+ SymbolHashMapEntry* entry() const { return _entry; }
+ void set_entry(SymbolHashMapEntry* entry) { _entry = entry; }
+ void clear() { _entry = NULL; }
+
+}; // End SymbolHashMapBucket class
+
+
+class SymbolHashMap: public CHeapObj<mtSymbol> {
+
+ private:
+ // Default number of entries in the table
+ enum SymbolHashMap_Constants {
+ _Def_HashMap_Size = 256
+ };
+
+ int _table_size;
+ SymbolHashMapBucket* _buckets;
+
+ void initialize_table(int table_size) {
+ _table_size = table_size;
+ _buckets = NEW_C_HEAP_ARRAY(SymbolHashMapBucket, table_size, mtSymbol);
+ for (int index = 0; index < table_size; index++) {
+ _buckets[index].clear();
+ }
+ }
+
+ public:
+
+ int table_size() const { return _table_size; }
+
+ SymbolHashMap() { initialize_table(_Def_HashMap_Size); }
+ SymbolHashMap(int table_size) { initialize_table(table_size); }
+
+ // hash P(31) from Kernighan & Ritchie
+ static unsigned int compute_hash(const char* str, int len) {
+ unsigned int hash = 0;
+ while (len-- > 0) {
+ hash = 31*hash + (unsigned) *str;
+ str++;
+ }
+ return hash;
+ }
+
+ SymbolHashMapEntry* bucket(int i) {
+ return _buckets[i].entry();
+ }
+
+ void add_entry(Symbol* sym, u2 value);
+ SymbolHashMapEntry* find_entry(Symbol* sym);
+
+ u2 symbol_to_value(Symbol* sym) {
+ SymbolHashMapEntry *entry = find_entry(sym);
+ return (entry == NULL) ? 0 : entry->value();
+ }
+
+ ~SymbolHashMap() {
+ SymbolHashMapEntry* next;
+ for (int i = 0; i < _table_size; i++) {
+ for (SymbolHashMapEntry* cur = bucket(i); cur != NULL; cur = next) {
+ next = cur->next();
+ delete(cur);
+ }
+ }
+ delete _buckets;
+ }
+}; // End SymbolHashMap class
+
+#endif // SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP