1.1 --- a/src/share/vm/oops/symbol.hpp Thu Mar 15 13:37:13 2012 +0100
1.2 +++ b/src/share/vm/oops/symbol.hpp Fri Mar 23 11:16:05 2012 -0400
1.3 @@ -1,5 +1,5 @@
1.4 /*
1.5 - * Copyright (c) 1997, 2011, Oracle and/or its affiliates. All rights reserved.
1.6 + * Copyright (c) 1997, 2012, Oracle and/or its affiliates. All rights reserved.
1.7 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.8 *
1.9 * This code is free software; you can redistribute it and/or modify it
1.10 @@ -27,6 +27,7 @@
1.11
1.12 #include "utilities/utf8.hpp"
1.13 #include "memory/allocation.hpp"
1.14 +#include "runtime/atomic.hpp"
1.15
1.16 // A Symbol is a canonicalized string.
1.17 // All Symbols reside in global SymbolTable and are reference counted.
1.18 @@ -95,7 +96,7 @@
1.19 // TempNewSymbol (passed in as a parameter) so the reference count on its symbol
1.20 // will be decremented when it goes out of scope.
1.21
1.22 -class Symbol : public CHeapObj {
1.23 +class Symbol : public ResourceObj {
1.24 friend class VMStructs;
1.25 friend class SymbolTable;
1.26 friend class MoveSymbols;
1.27 @@ -111,7 +112,7 @@
1.28 };
1.29
1.30 static int object_size(int length) {
1.31 - size_t size = heap_word_size(sizeof(Symbol) + length);
1.32 + size_t size = heap_word_size(sizeof(Symbol) + (length > 0 ? length - 1 : 0));
1.33 return align_object_size(size);
1.34 }
1.35
1.36 @@ -120,28 +121,25 @@
1.37 _body[index] = value;
1.38 }
1.39
1.40 - Symbol(const u1* name, int length);
1.41 - void* operator new(size_t size, int len);
1.42 + Symbol(const u1* name, int length, int refcount);
1.43 + void* operator new(size_t size, int len, TRAPS);
1.44 + void* operator new(size_t size, int len, Arena* arena, TRAPS);
1.45
1.46 public:
1.47 // Low-level access (used with care, since not GC-safe)
1.48 const jbyte* base() const { return &_body[0]; }
1.49
1.50 - int object_size() { return object_size(utf8_length()); }
1.51 + int object_size() { return object_size(utf8_length()); }
1.52
1.53 // Returns the largest size symbol we can safely hold.
1.54 - static int max_length() {
1.55 - return max_symbol_length;
1.56 - }
1.57 + static int max_length() { return max_symbol_length; }
1.58
1.59 - int identity_hash() {
1.60 - return _identity_hash;
1.61 - }
1.62 + int identity_hash() { return _identity_hash; }
1.63
1.64 // Reference counting. See comments above this class for when to use.
1.65 - int refcount() const { return _refcount; }
1.66 - void increment_refcount();
1.67 - void decrement_refcount();
1.68 + int refcount() const { return _refcount; }
1.69 + inline void increment_refcount();
1.70 + inline void decrement_refcount();
1.71
1.72 int byte_at(int index) const {
1.73 assert(index >=0 && index < _length, "symbol index overflow");
1.74 @@ -220,4 +218,26 @@
1.75 return (((uintptr_t)this < (uintptr_t)other) ? -1
1.76 : ((uintptr_t)this == (uintptr_t) other) ? 0 : 1);
1.77 }
1.78 +
1.79 +inline void Symbol::increment_refcount() {
1.80 + // Only increment the refcount if positive. If negative either
1.81 + // overflow has occurred or it is a permanent symbol in a read only
1.82 + // shared archive.
1.83 + if (_refcount >= 0) {
1.84 + Atomic::inc(&_refcount);
1.85 + NOT_PRODUCT(Atomic::inc(&_total_count);)
1.86 + }
1.87 +}
1.88 +
1.89 +inline void Symbol::decrement_refcount() {
1.90 + if (_refcount >= 0) {
1.91 + Atomic::dec(&_refcount);
1.92 +#ifdef ASSERT
1.93 + if (_refcount < 0) {
1.94 + print();
1.95 + assert(false, "reference count underflow for symbol");
1.96 + }
1.97 +#endif
1.98 + }
1.99 +}
1.100 #endif // SHARE_VM_OOPS_SYMBOL_HPP
