AuroraOpenALSoft/common/almalloc.h
2020-03-22 13:28:45 -07:00

310 lines
10 KiB
C++

#ifndef AL_MALLOC_H
#define AL_MALLOC_H
#include <algorithm>
#include <cstddef>
#include <iterator>
#include <limits>
#include <memory>
#include <new>
#include <type_traits>
#include <utility>
#include "pragmadefs.h"
void *al_malloc(size_t alignment, size_t size);
void *al_calloc(size_t alignment, size_t size);
void al_free(void *ptr) noexcept;
#define DEF_NEWDEL(T) \
void *operator new(size_t size) \
{ \
void *ret = al_malloc(alignof(T), size); \
if(!ret) throw std::bad_alloc(); \
return ret; \
} \
void *operator new[](size_t size) { return operator new(size); } \
void operator delete(void *block) noexcept { al_free(block); } \
void operator delete[](void *block) noexcept { operator delete(block); }
#define DEF_PLACE_NEWDEL() \
void *operator new(size_t /*size*/, void *ptr) noexcept { return ptr; } \
void *operator new[](size_t /*size*/, void *ptr) noexcept { return ptr; } \
void operator delete(void *block, void*) noexcept { al_free(block); } \
void operator delete(void *block) noexcept { al_free(block); } \
void operator delete[](void *block, void*) noexcept { al_free(block); } \
void operator delete[](void *block) noexcept { al_free(block); }
struct FamCount { size_t mCount; };
#define DEF_FAM_NEWDEL(T, FamMem) \
static constexpr size_t Sizeof(size_t count) noexcept \
{ return decltype(FamMem)::Sizeof(count, offsetof(T, FamMem)); } \
\
void *operator new(size_t /*size*/, FamCount fam) \
{ \
if(void *ret{al_malloc(alignof(T), T::Sizeof(fam.mCount))}) \
return ret; \
throw std::bad_alloc(); \
} \
void *operator new[](size_t /*size*/) = delete; \
void operator delete(void *block, FamCount) { al_free(block); } \
void operator delete(void *block) noexcept { al_free(block); } \
void operator delete[](void* /*block*/) = delete;
namespace al {
#define REQUIRES(...) typename std::enable_if<(__VA_ARGS__),int>::type = 0
template<typename T, std::size_t alignment=alignof(T)>
struct allocator {
using value_type = T;
using reference = T&;
using const_reference = const T&;
using pointer = T*;
using const_pointer = const T*;
using size_type = std::size_t;
using difference_type = std::ptrdiff_t;
using is_always_equal = std::true_type;
template<typename U>
struct rebind {
using other = allocator<U, (alignment<alignof(U))?alignof(U):alignment>;
};
allocator() = default;
template<typename U, std::size_t N>
constexpr allocator(const allocator<U,N>&) noexcept { }
T *allocate(std::size_t n)
{
if(n > std::numeric_limits<std::size_t>::max()/sizeof(T)) throw std::bad_alloc();
if(auto p = static_cast<T*>(al_malloc(alignment, n*sizeof(T)))) return p;
throw std::bad_alloc();
}
void deallocate(T *p, std::size_t) noexcept { al_free(p); }
};
template<typename T, std::size_t N, typename U, std::size_t M>
bool operator==(const allocator<T,N>&, const allocator<U,M>&) noexcept { return true; }
template<typename T, std::size_t N, typename U, std::size_t M>
bool operator!=(const allocator<T,N>&, const allocator<U,M>&) noexcept { return false; }
template<size_t alignment, typename T>
inline T* assume_aligned(T *ptr) noexcept
{
static_assert((alignment & (alignment-1)) == 0, "alignment must be a power of 2");
#ifdef __GNUC__
return static_cast<T*>(__builtin_assume_aligned(ptr, alignment));
#elif defined(_MSC_VER)
auto ptrval = reinterpret_cast<uintptr_t>(ptr);
if((ptrval&(alignment-1)) != 0) __assume(0);
return reinterpret_cast<T*>(ptrval);
#else
return ptr;
#endif
}
/* At least VS 2015 complains that 'ptr' is unused when the given type's
* destructor is trivial (a no-op). So disable that warning for this call.
*/
DIAGNOSTIC_PUSH
msc_pragma(warning(disable : 4100))
template<typename T>
inline void destroy_at(T *ptr) { ptr->~T(); }
DIAGNOSTIC_POP
template<typename T>
inline void destroy(T first, const T end)
{
while(first != end)
{
al::destroy_at(std::addressof(*first));
++first;
}
}
template<typename T, typename N, REQUIRES(std::is_integral<N>::value)>
inline T destroy_n(T first, N count)
{
if(count != 0)
{
do {
al::destroy_at(std::addressof(*first));
++first;
} while(--count);
}
return first;
}
template<typename T>
inline void uninitialized_default_construct(T first, const T last)
{
using ValueT = typename std::iterator_traits<T>::value_type;
T current{first};
try {
while(current != last)
{
::new (static_cast<void*>(std::addressof(*current))) ValueT;
++current;
}
}
catch(...) {
al::destroy(first, current);
throw;
}
}
template<typename T, typename N, REQUIRES(std::is_integral<N>::value)>
inline T uninitialized_default_construct_n(T first, N count)
{
using ValueT = typename std::iterator_traits<T>::value_type;
T current{first};
if(count != 0)
{
try {
do {
::new (static_cast<void*>(std::addressof(*current))) ValueT;
++current;
} while(--count);
}
catch(...) {
al::destroy(first, current);
throw;
}
}
return current;
}
template<typename T0, typename T1>
inline T1 uninitialized_move(T0 first, const T0 last, const T1 output)
{
using ValueT = typename std::iterator_traits<T1>::value_type;
T1 current{output};
try {
while(first != last)
{
::new (static_cast<void*>(std::addressof(*current))) ValueT{std::move(*first)};
++current;
++first;
}
}
catch(...) {
al::destroy(output, current);
throw;
}
return current;
}
template<typename T0, typename N, typename T1, REQUIRES(std::is_integral<N>::value)>
inline T1 uninitialized_move_n(T0 first, N count, const T1 output)
{
using ValueT = typename std::iterator_traits<T1>::value_type;
T1 current{output};
if(count != 0)
{
try {
do {
::new (static_cast<void*>(std::addressof(*current))) ValueT{std::move(*first)};
++current;
++first;
} while(--count);
}
catch(...) {
al::destroy(output, current);
throw;
}
}
return current;
}
/* A flexible array type. Used either standalone or at the end of a parent
* struct, with placement new, to have a run-time-sized array that's embedded
* with its size.
*/
template<typename T, size_t alignment=alignof(T)>
struct FlexArray {
using element_type = T;
using value_type = typename std::remove_cv<T>::type;
using index_type = size_t;
using difference_type = ptrdiff_t;
using pointer = T*;
using const_pointer = const T*;
using reference = T&;
using const_reference = const T&;
using iterator = pointer;
using const_iterator = const_pointer;
using reverse_iterator = std::reverse_iterator<iterator>;
using const_reverse_iterator = std::reverse_iterator<const_iterator>;
const index_type mSize;
DIAGNOSTIC_PUSH
std_pragma("GCC diagnostic ignored \"-Wpedantic\"")
msc_pragma(warning(disable : 4200))
alignas(alignment) element_type mArray[0];
DIAGNOSTIC_POP
static std::unique_ptr<FlexArray> Create(index_type count)
{
void *ptr{al_calloc(alignof(FlexArray), Sizeof(count))};
return std::unique_ptr<FlexArray>{new (ptr) FlexArray{count}};
}
static constexpr index_type Sizeof(index_type count, index_type base=0u) noexcept
{
return base +
std::max<index_type>(offsetof(FlexArray, mArray) + sizeof(T)*count, sizeof(FlexArray));
}
FlexArray(index_type size) : mSize{size}
{ al::uninitialized_default_construct_n(mArray, mSize); }
~FlexArray() { al::destroy_n(mArray, mSize); }
FlexArray(const FlexArray&) = delete;
FlexArray& operator=(const FlexArray&) = delete;
index_type size() const noexcept { return mSize; }
bool empty() const noexcept { return mSize == 0; }
pointer data() noexcept { return mArray; }
const_pointer data() const noexcept { return mArray; }
reference operator[](index_type i) noexcept { return mArray[i]; }
const_reference operator[](index_type i) const noexcept { return mArray[i]; }
reference front() noexcept { return mArray[0]; }
const_reference front() const noexcept { return mArray[0]; }
reference back() noexcept { return mArray[mSize-1]; }
const_reference back() const noexcept { return mArray[mSize-1]; }
iterator begin() noexcept { return mArray; }
const_iterator begin() const noexcept { return mArray; }
const_iterator cbegin() const noexcept { return mArray; }
iterator end() noexcept { return mArray + mSize; }
const_iterator end() const noexcept { return mArray + mSize; }
const_iterator cend() const noexcept { return mArray + mSize; }
reverse_iterator rbegin() noexcept { return end(); }
const_reverse_iterator rbegin() const noexcept { return end(); }
const_reverse_iterator crbegin() const noexcept { return cend(); }
reverse_iterator rend() noexcept { return begin(); }
const_reverse_iterator rend() const noexcept { return begin(); }
const_reverse_iterator crend() const noexcept { return cbegin(); }
DEF_PLACE_NEWDEL()
};
#undef REQUIRES
} // namespace al
#endif /* AL_MALLOC_H */