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Proper data alignment for allocator and lazy constructor

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This commit is contained in:
Pavel Kirienko 2014-03-28 13:47:21 +04:00
parent c54b3314e4
commit 4886e2194f
2 changed files with 29 additions and 17 deletions
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16
libuavcan/include/uavcan/dynamic_memory.hpp
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@ -117,7 +117,13 @@ class PoolAllocator : public IPoolAllocator, Noncopyable
};
Node* free_list_;
uint8_t pool_[PoolSize] __attribute__((aligned(16))); // TODO: compiler-independent alignment
union
{
uint8_t bytes[PoolSize];
long double _aligner1;
long long _aligner2;
Node _aligner3;
} pool_;
// Noncopyable
PoolAllocator(const PoolAllocator&);
@ -127,9 +133,9 @@ public:
static const int NumBlocks = int(PoolSize / BlockSize);
PoolAllocator()
: free_list_(reinterpret_cast<Node*>(pool_)) // TODO: alignment
: free_list_(reinterpret_cast<Node*>(pool_.bytes))
{
memset(pool_, 0, PoolSize);
memset(pool_.bytes, 0, PoolSize);
for (int i = 0; i < NumBlocks - 1; i++)
{
free_list_[i].next = free_list_ + i + 1;
@ -165,8 +171,8 @@ public:
bool isInPool(const void* ptr) const
{
return
ptr >= pool_ &&
ptr < (pool_ + PoolSize);
ptr >= pool_.bytes &&
ptr < (pool_.bytes + PoolSize);
}
std::size_t getBlockSize() const { return BlockSize; }

30
libuavcan/include/uavcan/util/lazy_constructor.hpp
View File

@ -18,7 +18,13 @@ namespace uavcan
template <typename T>
class LazyConstructor
{
unsigned char data_[sizeof(T)] __attribute__((aligned(16))); // TODO: compiler-independent alignment
union
{
unsigned char pool[sizeof(T)];
long double _aligner1;
long long _aligner2;
} data_;
T* ptr_;
void ensureConstructed() const
@ -47,13 +53,13 @@ public:
LazyConstructor()
: ptr_(NULL)
{
std::fill(data_, data_ + sizeof(T), 0);
std::fill(data_.pool, data_.pool + sizeof(T), 0);
}
LazyConstructor(const LazyConstructor<T>& rhs)
: ptr_(NULL)
{
std::fill(data_, data_ + sizeof(T), 0);
std::fill(data_.pool, data_.pool + sizeof(T), 0);
if (rhs)
{
construct<const T&>(*rhs); // Invoke copy constructor
@ -89,13 +95,13 @@ public:
ptr_->~T();
}
ptr_ = NULL;
std::fill(data_, data_ + sizeof(T), 0);
std::fill(data_.pool, data_.pool + sizeof(T), 0);
}
void construct()
{
ensureNotConstructed();
ptr_ = new (static_cast<void*>(data_)) T();
ptr_ = new (static_cast<void*>(data_.pool)) T();
}
// MAX_ARGS = 6
@ -104,7 +110,7 @@ public:
// void construct(%s)
// {
// ensureNotConstructed();
// ptr_ = new (static_cast<void*>(data_)) T(%s);
// ptr_ = new (static_cast<void*>(data_.pool)) T(%s);
// }'''
// for nargs in range(1, MAX_ARGS + 1):
// nums = [(x + 1) for x in range(nargs)]
@ -117,21 +123,21 @@ public:
void construct(typename ParamType<P1>::Type p1)
{
ensureNotConstructed();
ptr_ = new (static_cast<void*>(data_)) T(p1);
ptr_ = new (static_cast<void*>(data_.pool)) T(p1);
}
template <typename P1, typename P2>
void construct(typename ParamType<P1>::Type p1, typename ParamType<P2>::Type p2)
{
ensureNotConstructed();
ptr_ = new (static_cast<void*>(data_)) T(p1, p2);
ptr_ = new (static_cast<void*>(data_.pool)) T(p1, p2);
}
template <typename P1, typename P2, typename P3>
void construct(typename ParamType<P1>::Type p1, typename ParamType<P2>::Type p2, typename ParamType<P3>::Type p3)
{
ensureNotConstructed();
ptr_ = new (static_cast<void*>(data_)) T(p1, p2, p3);
ptr_ = new (static_cast<void*>(data_.pool)) T(p1, p2, p3);
}
template <typename P1, typename P2, typename P3, typename P4>
@ -139,7 +145,7 @@ public:
typename ParamType<P4>::Type p4)
{
ensureNotConstructed();
ptr_ = new (static_cast<void*>(data_)) T(p1, p2, p3, p4);
ptr_ = new (static_cast<void*>(data_.pool)) T(p1, p2, p3, p4);
}
template <typename P1, typename P2, typename P3, typename P4, typename P5>
@ -147,7 +153,7 @@ public:
typename ParamType<P4>::Type p4, typename ParamType<P5>::Type p5)
{
ensureNotConstructed();
ptr_ = new (static_cast<void*>(data_)) T(p1, p2, p3, p4, p5);
ptr_ = new (static_cast<void*>(data_.pool)) T(p1, p2, p3, p4, p5);
}
template <typename P1, typename P2, typename P3, typename P4, typename P5, typename P6>
@ -155,7 +161,7 @@ public:
typename ParamType<P4>::Type p4, typename ParamType<P5>::Type p5, typename ParamType<P6>::Type p6)
{
ensureNotConstructed();
ptr_ = new (static_cast<void*>(data_)) T(p1, p2, p3, p4, p5, p6);
ptr_ = new (static_cast<void*>(data_.pool)) T(p1, p2, p3, p4, p5, p6);
}
};