jdk8-mips64-public/hotspot: src/share/vm/oops/constantPool.hpp@46f6f063b272 (annotated)

src/share/vm/oops/constantPool.hpp@46f6f063b272 (annotated)

src/share/vm/oops/constantPool.hpp

Thu, 21 Mar 2013 09:27:54 +0100

author: roland
date: Thu, 21 Mar 2013 09:27:54 +0100
changeset 4860: 46f6f063b272
parent 4643: f16e75e0cf11
child 4983: 15a99ca4ee34
permissions: -rw-r--r--

7153771: array bound check elimination for c1
Summary: when possible optimize out array bound checks, inserting predicates when needed.
Reviewed-by: never, kvn, twisti
Contributed-by: thomaswue <thomas.wuerthinger@oracle.com>

 /*
  * Copyright (c) 1997, 2013, 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 KlassSizeStats;
 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
   InstanceKlass*       _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;
   enum {
     _has_preresolution = 1,           // Flags
     _on_stack          = 2
   };
   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;
   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; }
   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) {
     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_preresolution() const            { return (_flags & _has_preresolution) != 0; }
   void set_has_preresolution()              { _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);
   // 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; }
   // 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);
   }
   // 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);
   // 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;
   }
   oop pseudo_string_at(int which) {
     assert(tag_at(which).is_string(), "Corrupted constant pool");
     assert(unresolved_string_at(which) == NULL, "shouldn't have symbol");
     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(EnableInvokeDynamic, "");
     assert(tag_at(which).is_string(), "Corrupted constant pool");
     unresolved_string_at_put(which, NULL); // indicates patched string
     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);
   // 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(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();
   }
   // Sizing (in words)
   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()); }
 #if INCLUDE_SERVICES
   void collect_statistics(KlassSizeStats *sz) const;
 #endif
   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 bool    has_method_type_at_if_loaded      (constantPoolHandle this_oop, int which);
   static oop         method_type_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);
   static void copy_operands(constantPoolHandle from_cp, constantPoolHandle to_cp, TRAPS);
   int  find_matching_entry(int pattern_i, 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; }
   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

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/oops/constantPool.hpp@46f6f063b272 (annotated)

src/share/vm/oops/constantPool.hpp