Mercurial > hg > graal-compiler
view src/share/vm/utilities/sizes.hpp @ 7172:bbc14465e7db
8003689: MemTracker::init_tracking_options() reads outside array if commandline argument is empty
Summary: Fixed potential buffer overrun when giving empty option to NativeMemoryTracking commandline option
Reviewed-by: ctornqvi, hseigel, kvn
author | zgu |
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date | Wed, 28 Nov 2012 09:19:38 -0500 |
parents | f95d63e2154a |
children |
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/* * Copyright (c) 2000, 2010, 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_UTILITIES_SIZES_HPP #define SHARE_VM_UTILITIES_SIZES_HPP #include "memory/allocation.hpp" #include "utilities/globalDefinitions.hpp" // The following two classes are used to represent 'sizes' and 'offsets' in the VM; // they serve as 'unit' types. ByteSize is used for sizes measured in bytes, while // WordSize is used for sizes measured in machine words (i.e., 32bit or 64bit words // depending on platform). // // The classes are defined with friend functions operating on them instead of member // functions so that they (the classes) can be re-#define'd to int types in optimized // mode. This allows full type checking and maximum safety in debug mode, and full // optimizations (constant folding) and zero overhead (time and space wise) in the // optimized build (some compilers do not optimize one-element value classes but // instead create an object in memory - thus the overhead may be significant). // // Note: 1) DO NOT add new overloaded friend functions that do not have a unique function // function name but require signature types for resolution. This will not work // in optimized mode as both, ByteSize and WordSize are mapped to the same type // and thus the distinction would not be possible anymore (=> compiler errors). // // 2) DO NOT add non-static member functions as they cannot be mapped so something // compilable in the optimized build. Static member functions could be added // but require a corresponding class definition in the optimized build. // // These classes should help doing a transition from (currently) word-size based offsets // to byte-size based offsets in the VM (this will be important if we desire to pack // objects more densely in the VM for 64bit machines). Such a transition should proceed // in two steps to minimize the risk of introducing hard-to-find bugs: // // a) first transition the whole VM into a form where all sizes are strongly typed // b) change all WordSize's to ByteSize's where desired and fix the compilation errors #ifdef ASSERT class ByteSize VALUE_OBJ_CLASS_SPEC { private: int _size; // Note: This constructor must be private to avoid implicit conversions! ByteSize(int size) { _size = size; } public: // constructors inline friend ByteSize in_ByteSize(int size); // accessors inline friend int in_bytes(ByteSize x); // operators friend ByteSize operator + (ByteSize x, ByteSize y) { return ByteSize(in_bytes(x) + in_bytes(y)); } friend ByteSize operator - (ByteSize x, ByteSize y) { return ByteSize(in_bytes(x) - in_bytes(y)); } friend ByteSize operator * (ByteSize x, int y) { return ByteSize(in_bytes(x) * y ); } // comparison friend bool operator == (ByteSize x, ByteSize y) { return in_bytes(x) == in_bytes(y); } friend bool operator != (ByteSize x, ByteSize y) { return in_bytes(x) != in_bytes(y); } friend bool operator < (ByteSize x, ByteSize y) { return in_bytes(x) < in_bytes(y); } friend bool operator <= (ByteSize x, ByteSize y) { return in_bytes(x) <= in_bytes(y); } friend bool operator > (ByteSize x, ByteSize y) { return in_bytes(x) > in_bytes(y); } friend bool operator >= (ByteSize x, ByteSize y) { return in_bytes(x) >= in_bytes(y); } }; inline ByteSize in_ByteSize(int size) { return ByteSize(size); } inline int in_bytes(ByteSize x) { return x._size; } class WordSize VALUE_OBJ_CLASS_SPEC { private: int _size; // Note: This constructor must be private to avoid implicit conversions! WordSize(int size) { _size = size; } public: // constructors inline friend WordSize in_WordSize(int size); // accessors inline friend int in_words(WordSize x); // operators friend WordSize operator + (WordSize x, WordSize y) { return WordSize(in_words(x) + in_words(y)); } friend WordSize operator - (WordSize x, WordSize y) { return WordSize(in_words(x) - in_words(y)); } friend WordSize operator * (WordSize x, int y) { return WordSize(in_words(x) * y ); } // comparison friend bool operator == (WordSize x, WordSize y) { return in_words(x) == in_words(y); } friend bool operator != (WordSize x, WordSize y) { return in_words(x) != in_words(y); } friend bool operator < (WordSize x, WordSize y) { return in_words(x) < in_words(y); } friend bool operator <= (WordSize x, WordSize y) { return in_words(x) <= in_words(y); } friend bool operator > (WordSize x, WordSize y) { return in_words(x) > in_words(y); } friend bool operator >= (WordSize x, WordSize y) { return in_words(x) >= in_words(y); } }; inline WordSize in_WordSize(int size) { return WordSize(size); } inline int in_words(WordSize x) { return x._size; } #else // ASSERT // The following definitions must match the corresponding friend declarations // in the Byte/WordSize classes if they are typedef'ed to be int. This will // be the case in optimized mode to ensure zero overhead for these types. // // Note: If a compiler does not inline these function calls away, one may // want to use #define's to make sure full optimization (constant // folding in particular) is possible. typedef int ByteSize; inline ByteSize in_ByteSize(int size) { return size; } inline int in_bytes (ByteSize x) { return x; } typedef int WordSize; inline WordSize in_WordSize(int size) { return size; } inline int in_words (WordSize x) { return x; } #endif // ASSERT // Use the following #define to get C++ field member offsets #define byte_offset_of(klass,field) in_ByteSize((int)offset_of(klass, field)) #endif // SHARE_VM_UTILITIES_SIZES_HPP