Mercurial > hg > truffle
diff src/share/vm/oops/constantPool.hpp @ 6725:da91efe96a93
6964458: Reimplement class meta-data storage to use native memory
Summary: Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes
Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland
Contributed-by: jmasa <jon.masamitsu@oracle.com>, stefank <stefan.karlsson@oracle.com>, mgerdin <mikael.gerdin@oracle.com>, never <tom.rodriguez@oracle.com>
author | coleenp |
---|---|
date | Sat, 01 Sep 2012 13:25:18 -0400 |
parents | src/share/vm/oops/constantPoolOop.hpp@1d7922586cf6 |
children | fa6e618671d7 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/oops/constantPool.hpp Sat Sep 01 13:25:18 2012 -0400 @@ -0,0 +1,928 @@ +/* + * Copyright (c) 1997, 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_CONSTANTPOOLOOP_HPP +#define SHARE_VM_OOPS_CONSTANTPOOLOOP_HPP + +#include "oops/arrayOop.hpp" +#include "oops/cpCache.hpp" +#include "oops/objArrayOop.hpp" +#include "oops/symbol.hpp" +#include "oops/typeArrayOop.hpp" +#include "runtime/handles.hpp" +#include "utilities/constantTag.hpp" +#ifdef TARGET_ARCH_x86 +# include "bytes_x86.hpp" +#endif +#ifdef TARGET_ARCH_sparc +# include "bytes_sparc.hpp" +#endif +#ifdef TARGET_ARCH_zero +# include "bytes_zero.hpp" +#endif +#ifdef TARGET_ARCH_arm +# include "bytes_arm.hpp" +#endif +#ifdef TARGET_ARCH_ppc +# include "bytes_ppc.hpp" +#endif + +// 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 { + intptr_t _ptr; + public: + CPSlot(intptr_t ptr): _ptr(ptr) {} + CPSlot(Klass* ptr): _ptr((intptr_t)ptr) {} + CPSlot(Symbol* ptr): _ptr((intptr_t)ptr | 1) {} + + intptr_t value() { return _ptr; } + bool is_resolved() { return (_ptr & 1) == 0; } + bool is_unresolved() { return (_ptr & 1) == 1; } + + Symbol* get_symbol() { + assert(is_unresolved(), "bad call"); + return (Symbol*)(_ptr & ~1); + } + Klass* get_klass() { + assert(is_resolved(), "bad call"); + return (Klass*)_ptr; + } +}; + +class ConstantPool : public Metadata { + friend class VMStructs; + friend class BytecodeInterpreter; // Directly extracts an oop in the pool for fast instanceof/checkcast + friend class Universe; // For null constructor + private: + Array<u1>* _tags; // the tag array describing the constant pool's contents + ConstantPoolCache* _cache; // the cache holding interpreter runtime information + Klass* _pool_holder; // the corresponding class + Array<u2>* _operands; // for variable-sized (InvokeDynamic) nodes, usually empty + + // Array of resolved objects from the constant pool and map from resolved + // object index to original constant pool index + jobject _resolved_references; + Array<u2>* _reference_map; + + int _flags; // a few header bits to describe contents for GC + int _length; // number of elements in the array + + bool _on_stack; // Redefined method still executing refers to this constant pool. + + union { + // set for CDS to restore resolved references + int _resolved_reference_length; + // only set to non-zero if constant pool is merged by RedefineClasses + int _orig_length; + } _saved; + + Monitor* _lock; + + 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); } + + void set_operands(Array<u2>* operands) { _operands = operands; } + + enum FlagBit { + FB_has_invokedynamic = 1, + FB_has_pseudo_string = 2, + FB_has_preresolution = 3 + }; + + int flags() const { return _flags; } + void set_flags(int f) { _flags = f; } + bool flag_at(FlagBit fb) const { return (_flags & (1 << (int)fb)) != 0; } + void set_flag_at(FlagBit fb); + // no clear_flag_at function; they only increase + + private: + intptr_t* base() const { return (intptr_t*) (((char*) this) + sizeof(ConstantPool)); } + + CPSlot slot_at(int which) { + assert(is_within_bounds(which), "index out of bounds"); + // 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_pseudo_string() const { return flag_at(FB_has_pseudo_string); } + bool has_invokedynamic() const { return flag_at(FB_has_invokedynamic); } + bool has_preresolution() const { return flag_at(FB_has_preresolution); } + void set_pseudo_string() { set_flag_at(FB_has_pseudo_string); } + void set_invokedynamic() { set_flag_at(FB_has_invokedynamic); } + void set_preresolution() { set_flag_at(FB_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 _on_stack; } + void set_on_stack(const bool value); + + // Klass holding pool + Klass* pool_holder() const { return _pool_holder; } + void set_pool_holder(Klass* k) { _pool_holder = k; } + Klass** pool_holder_addr() { return &_pool_holder; } + + // Interpreter runtime support + ConstantPoolCache* cache() const { return _cache; } + void set_cache(ConstantPoolCache* cache){ _cache = cache; } + + // Create object cache in the constant pool + void initialize_resolved_references(ClassLoaderData* loader_data, + 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); + + // 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_references_offset_in_bytes() { return offset_of(ConstantPool, _resolved_references); } + static int reference_map_offset_in_bytes() { return offset_of(ConstantPool, _reference_map); } + + // Storing constants + + void klass_at_put(int which, Klass* k) { + assert(k != NULL, "resolved class shouldn't be null"); + assert(is_within_bounds(which), "index out of bounds"); + OrderAccess::release_store_ptr((Klass* volatile *)obj_at_addr_raw(which), k); + // The interpreter assumes when the tag is stored, the klass is resolved + // and the Klass* is a klass rather than a Symbol*, so we need + // hardware store ordering here. + release_tag_at_put(which, JVM_CONSTANT_Class); + } + + // 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; + } + + // Temporary until actual use + void unresolved_klass_at_put(int which, Symbol* s) { + release_tag_at_put(which, JVM_CONSTANT_UnresolvedClass); + slot_at_put(which, s); + } + + 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); + *symbol_at_addr(which) = 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) { + resolved_references()->obj_at_put(obj_index, str); + } + + void set_object_tag_at(int which) { + release_tag_at_put(which, JVM_CONSTANT_Object); + } + + void object_at_put(int which, oop obj) { + resolved_references()->obj_at_put(cp_to_object_index(which), obj); + } + + // 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, CHECK_NULL); + } + + Symbol* klass_name_at(int which); // Returns the name, w/o resolving. + + Klass* resolved_klass_at(int which) { // 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. + return CPSlot((Klass*)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which))).get_klass(); + } + + // This method should only be used with a cpool lock or during parsing or gc + Symbol* unresolved_klass_at(int which) { // Temporary until actual use + Symbol* s = CPSlot((Symbol*)OrderAccess::load_ptr_acquire(obj_at_addr_raw(which))).get_symbol(); + // check that the klass is still unresolved. + assert(tag_at(which).is_unresolved_klass(), "Corrupted constant pool"); + return s; + } + + // RedefineClasses() API support: + Symbol* klass_at_noresolve(int which) { return klass_name_at(which); } + + 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) { + 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); + + oop object_at(int which) { + assert(tag_at(which).is_object(), "Corrupted constant pool"); + int obj_index = cp_to_object_index(which); + return resolved_references()->obj_at(obj_index); + } + + // A "pseudo-string" is an non-string oop that has found is way into + // a String entry. + // Under EnableInvokeDynamic 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) { + // A pseudo string is a string that doesn't have a symbol in the cpSlot + return unresolved_string_at(which) == NULL; + } + + oop pseudo_string_at(int which, int obj_index) { + assert(tag_at(which).is_string(), "Corrupted constant pool"); + assert(unresolved_string_at(which) == NULL, "shouldn't have symbol"); + oop s = resolved_references()->obj_at(obj_index); + return s; + } + + void pseudo_string_at_put(int which, int obj_index, oop x) { + assert(EnableInvokeDynamic, ""); + set_pseudo_string(); // mark header + assert(tag_at(which).is_string(), "Corrupted constant pool"); + 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* s = *symbol_at_addr(which); + return s; + } + + // 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. + // Caller is responsible for checking for pseudo-strings. + 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(), "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(), "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(), "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] + }; + 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); } + + // 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); + + // 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 remove_unshareable_info(); + void restore_unshareable_info(TRAPS); + bool resolve_class_constants(TRAPS); + + 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(instanceKlassHandle 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(); + } + + static int header_size() { return sizeof(ConstantPool)/HeapWordSize; } + static int size(int length) { return align_object_size(header_size() + length); } + int size() const { return size(length()); } + + friend class ClassFileParser; + friend class SystemDictionary; + + // Used by compiler to prevent classloading. + static Method* method_at_if_loaded (constantPoolHandle this_oop, int which); + static bool has_appendix_at_if_loaded (constantPoolHandle this_oop, int which); + static oop appendix_at_if_loaded (constantPoolHandle this_oop, int which); + static Klass* klass_at_if_loaded (constantPoolHandle this_oop, int which); + static Klass* klass_ref_at_if_loaded (constantPoolHandle this_oop, int which); + // Same as above - but does LinkResolving. + static Klass* klass_ref_at_if_loaded_check(constantPoolHandle this_oop, int which, TRAPS); + + // 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(jobject s) { _resolved_references = s; } + Array<u2>* reference_map() const { return _reference_map; } + void set_reference_map(Array<u2>* o) { _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); + + int remap_instruction_operand_from_cache(int operand); // operand must be biased by CPCACHE_INDEX_TAG + + // 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(constantPoolHandle this_oop, KlassHandle 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(constantPoolHandle this_oop, int which, TRAPS); + static oop string_at_impl(constantPoolHandle this_oop, int which, int obj_index, TRAPS); + + // Resolve string constants (to prevent allocation during compilation) + static void resolve_string_constants_impl(constantPoolHandle this_oop, TRAPS); + + static oop resolve_constant_at_impl(constantPoolHandle this_oop, int index, int cache_index, TRAPS); + static void save_and_throw_exception(constantPoolHandle this_oop, int which, int tag_value, TRAPS); + static oop resolve_bootstrap_specifier_at_impl(constantPoolHandle this_oop, int index, TRAPS); + + public: + // Merging ConstantPool* support: + bool compare_entry_to(int index1, constantPoolHandle cp2, int index2, TRAPS); + void copy_cp_to(int start_i, int end_i, 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(constantPoolHandle from_cp, int start_i, int end_i, constantPoolHandle to_cp, int to_i, TRAPS); + static void copy_entry_to(constantPoolHandle from_cp, int from_i, constantPoolHandle to_cp, int to_i, TRAPS); + int find_matching_entry(int pattern_i, constantPoolHandle search_cp, TRAPS); + int orig_length() const { return _saved._orig_length; } + void set_orig_length(int orig_length) { _saved._orig_length = orig_length; } + + void set_resolved_reference_length(int length) { _saved._resolved_reference_length = length; } + int resolved_reference_length() const { return _saved._resolved_reference_length; } + void set_lock(Monitor* lock) { _lock = lock; } + Monitor* lock() { return _lock; } + + // 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