llvm-capstone/libcxx/include/__debug
Eric Fiselier 40492ba417 Fix undefined behavior in __hash_table
Summary:
This patch attempts to fix the undefined behavior in __hash_table by changing the node pointer types used throughout. The pointer types are changed for raw pointers in the current ABI and for fancy pointers in ABI V2 (since the fancy pointer types may not be ABI compatible).

The UB in `__hash_table` arises because tree downcasts the embedded end node and then deferences that pointer. Currently there are 2 node types in __hash_table:

* `__hash_node_base` which contains the `__next_` pointer.
* `__hash_node` which contains `__hash_` and `__value_`.

Currently the bucket list, iterators, and `__next_` pointers store pointers to `__hash_node` even though they all need to store `__hash_node_base` pointers.
This patch makes that change by introducing a `__next_pointer` typedef which is a pointer to `__hash_node` in the current ABI and `__hash_node_base` afterwards.

One notable change is to the type of `__bucket_list` which used to be defined as `unique_ptr<__node_pointer[], ...>` and is now `unique_ptr<__next_pointer[], ...>` meaning that we now allocate and deallocate different types using a different allocator. I'm going to give this part of the change more thought since it may introduce compatibility issues.

This change is similar to D20786.



Reviewers: mclow.lists, EricWF

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D20787

llvm-svn: 276533
2016-07-23 20:36:55 +00:00

236 lines
6.1 KiB
C++

// -*- C++ -*-
//===--------------------------- __debug ----------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is dual licensed under the MIT and the University of Illinois Open
// Source Licenses. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef _LIBCPP_DEBUG_H
#define _LIBCPP_DEBUG_H
#include <__config>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif
#if _LIBCPP_DEBUG_LEVEL >= 1
# include <cstdlib>
# include <cstdio>
# include <cstddef>
# ifndef _LIBCPP_ASSERT
# define _LIBCPP_ASSERT(x, m) ((x) ? (void)0 : (_VSTD::fprintf(stderr, "%s\n", m), _VSTD::abort()))
# endif
#endif
#if _LIBCPP_DEBUG_LEVEL >= 2
#ifndef _LIBCPP_DEBUG_ASSERT
#define _LIBCPP_DEBUG_ASSERT(x, m) _LIBCPP_ASSERT(x, m)
#endif
#define _LIBCPP_DEBUG_MODE(...) __VA_ARGS__
#endif
#ifndef _LIBCPP_ASSERT
# define _LIBCPP_ASSERT(x, m) ((void)0)
#endif
#ifndef _LIBCPP_DEBUG_ASSERT
# define _LIBCPP_DEBUG_ASSERT(x, m) ((void)0)
#endif
#ifndef _LIBCPP_DEBUG_MODE
#define _LIBCPP_DEBUG_MODE(...) ((void)0)
#endif
#if _LIBCPP_DEBUG_LEVEL >= 2
_LIBCPP_BEGIN_NAMESPACE_STD
struct _LIBCPP_TYPE_VIS __c_node;
struct _LIBCPP_TYPE_VIS __i_node
{
void* __i_;
__i_node* __next_;
__c_node* __c_;
#ifndef _LIBCPP_HAS_NO_DELETED_FUNCTIONS
__i_node(const __i_node&) = delete;
__i_node& operator=(const __i_node&) = delete;
#else
private:
__i_node(const __i_node&);
__i_node& operator=(const __i_node&);
public:
#endif
_LIBCPP_INLINE_VISIBILITY
__i_node(void* __i, __i_node* __next, __c_node* __c)
: __i_(__i), __next_(__next), __c_(__c) {}
~__i_node();
};
struct _LIBCPP_TYPE_VIS __c_node
{
void* __c_;
__c_node* __next_;
__i_node** beg_;
__i_node** end_;
__i_node** cap_;
#ifndef _LIBCPP_HAS_NO_DELETED_FUNCTIONS
__c_node(const __c_node&) = delete;
__c_node& operator=(const __c_node&) = delete;
#else
private:
__c_node(const __c_node&);
__c_node& operator=(const __c_node&);
public:
#endif
_LIBCPP_INLINE_VISIBILITY
__c_node(void* __c, __c_node* __next)
: __c_(__c), __next_(__next), beg_(nullptr), end_(nullptr), cap_(nullptr) {}
virtual ~__c_node();
virtual bool __dereferenceable(const void*) const = 0;
virtual bool __decrementable(const void*) const = 0;
virtual bool __addable(const void*, ptrdiff_t) const = 0;
virtual bool __subscriptable(const void*, ptrdiff_t) const = 0;
void __add(__i_node* __i);
_LIBCPP_HIDDEN void __remove(__i_node* __i);
};
template <class _Cont>
struct _C_node
: public __c_node
{
_C_node(void* __c, __c_node* __n)
: __c_node(__c, __n) {}
virtual bool __dereferenceable(const void*) const;
virtual bool __decrementable(const void*) const;
virtual bool __addable(const void*, ptrdiff_t) const;
virtual bool __subscriptable(const void*, ptrdiff_t) const;
};
template <class _Cont>
bool
_C_node<_Cont>::__dereferenceable(const void* __i) const
{
typedef typename _Cont::const_iterator iterator;
const iterator* __j = static_cast<const iterator*>(__i);
_Cont* _Cp = static_cast<_Cont*>(__c_);
return _Cp->__dereferenceable(__j);
}
template <class _Cont>
bool
_C_node<_Cont>::__decrementable(const void* __i) const
{
typedef typename _Cont::const_iterator iterator;
const iterator* __j = static_cast<const iterator*>(__i);
_Cont* _Cp = static_cast<_Cont*>(__c_);
return _Cp->__decrementable(__j);
}
template <class _Cont>
bool
_C_node<_Cont>::__addable(const void* __i, ptrdiff_t __n) const
{
typedef typename _Cont::const_iterator iterator;
const iterator* __j = static_cast<const iterator*>(__i);
_Cont* _Cp = static_cast<_Cont*>(__c_);
return _Cp->__addable(__j, __n);
}
template <class _Cont>
bool
_C_node<_Cont>::__subscriptable(const void* __i, ptrdiff_t __n) const
{
typedef typename _Cont::const_iterator iterator;
const iterator* __j = static_cast<const iterator*>(__i);
_Cont* _Cp = static_cast<_Cont*>(__c_);
return _Cp->__subscriptable(__j, __n);
}
class _LIBCPP_TYPE_VIS __libcpp_db
{
__c_node** __cbeg_;
__c_node** __cend_;
size_t __csz_;
__i_node** __ibeg_;
__i_node** __iend_;
size_t __isz_;
__libcpp_db();
public:
#ifndef _LIBCPP_HAS_NO_DELETED_FUNCTIONS
__libcpp_db(const __libcpp_db&) = delete;
__libcpp_db& operator=(const __libcpp_db&) = delete;
#else
private:
__libcpp_db(const __libcpp_db&);
__libcpp_db& operator=(const __libcpp_db&);
public:
#endif
~__libcpp_db();
class __db_c_iterator;
class __db_c_const_iterator;
class __db_i_iterator;
class __db_i_const_iterator;
__db_c_const_iterator __c_end() const;
__db_i_const_iterator __i_end() const;
template <class _Cont>
_LIBCPP_INLINE_VISIBILITY
void __insert_c(_Cont* __c)
{
__c_node* __n = __insert_c(static_cast<void*>(__c));
::new(__n) _C_node<_Cont>(__n->__c_, __n->__next_);
}
void __insert_i(void* __i);
__c_node* __insert_c(void* __c);
void __erase_c(void* __c);
void __insert_ic(void* __i, const void* __c);
void __iterator_copy(void* __i, const void* __i0);
void __erase_i(void* __i);
void* __find_c_from_i(void* __i) const;
void __invalidate_all(void* __c);
__c_node* __find_c_and_lock(void* __c) const;
__c_node* __find_c(void* __c) const;
void unlock() const;
void swap(void* __c1, void* __c2);
bool __dereferenceable(const void* __i) const;
bool __decrementable(const void* __i) const;
bool __addable(const void* __i, ptrdiff_t __n) const;
bool __subscriptable(const void* __i, ptrdiff_t __n) const;
bool __less_than_comparable(const void* __i, const void* __j) const;
private:
_LIBCPP_HIDDEN
__i_node* __insert_iterator(void* __i);
_LIBCPP_HIDDEN
__i_node* __find_iterator(const void* __i) const;
friend _LIBCPP_FUNC_VIS __libcpp_db* __get_db();
};
_LIBCPP_FUNC_VIS __libcpp_db* __get_db();
_LIBCPP_FUNC_VIS const __libcpp_db* __get_const_db();
_LIBCPP_END_NAMESPACE_STD
#endif
#endif // _LIBCPP_DEBUG_H