blender/intern/cycles/util/util_stack_allocator.h
Sergey Sharybin 42fd1b9abe Cycles: Fix issues with stack allocator in MSVC
Couple of issues here:

- Was a bug in heap memory allocation when run out
  of allowed stack memory.

- Debug MSVC was failing because it uses separate
  allocator for some sort of internal proxy thing,
  which seems to be unable to be using stack memory
  because allocator is being created in non-persistent
  stack location.
2016-04-25 13:50:27 +02:00

171 lines
3.2 KiB
C++

/*
* Copyright 2011-2016 Blender Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef __UTIL_STACK_ALLOCATOR_H__
#define __UTIL_STACK_ALLOCATOR_H__
#include <cstddef>
#include <memory>
#include "util_debug.h"
#include "util_types.h"
CCL_NAMESPACE_BEGIN
/* Stack allocator for the use with STL. */
template <int SIZE, typename T>
class ccl_try_align(16) StackAllocator {
public:
typedef size_t size_type;
typedef ptrdiff_t difference_type;
typedef T *pointer;
typedef const T *const_pointer;
typedef T& reference;
typedef const T& const_reference;
typedef T value_type;
/* Allocator construction/destruction. */
StackAllocator()
: pointer_(0),
use_stack_(true) {}
StackAllocator(const StackAllocator&)
: pointer_(0),
use_stack_(true) {}
template <class U>
StackAllocator(const StackAllocator<SIZE, U>&)
: pointer_(0),
use_stack_(false) {}
/* Memory allocation/deallocation. */
T *allocate(size_t n, const void *hint = 0)
{
(void)hint;
if(n == 0) {
return NULL;
}
if(pointer_ + n >= SIZE || use_stack_ == false) {
size_t size = n * sizeof(T);
util_guarded_mem_alloc(size);
T *mem;
#ifdef WITH_BLENDER_GUARDEDALLOC
mem = (T*)MEM_mallocN_aligned(size, 16, "Cycles Alloc");
#else
mem = (T*)malloc(size);
#endif
if(mem == NULL) {
throw std::bad_alloc();
}
return mem;
}
T *mem = &data_[pointer_];
pointer_ += n;
return mem;
}
void deallocate(T *p, size_t n)
{
if(p == NULL) {
return;
}
if(p < data_ || p >= data_ + SIZE) {
util_guarded_mem_free(n * sizeof(T));
#ifdef WITH_BLENDER_GUARDEDALLOC
MEM_freeN(p);
#else
free(p);
#endif
return;
}
/* We don't support memory free for the stack allocator. */
}
/* Address of an reference. */
T *address(T& x) const
{
return &x;
}
const T *address(const T& x) const
{
return &x;
}
/* Object construction/destruction. */
void construct(T *p, const T& val)
{
if(p != NULL) {
new ((T *)p) T(val);
}
}
void destroy(T *p)
{
p->~T();
}
/* Maximum allocation size. */
size_t max_size() const
{
return size_t(-1);
}
/* Rebind to other ype of allocator. */
template <class U>
struct rebind {
typedef StackAllocator<SIZE, U> other;
};
/* Operators */
template <class U>
inline StackAllocator& operator=(const StackAllocator<SIZE, U>&)
{
return *this;
}
StackAllocator<SIZE, T>& operator=(const StackAllocator&)
{
return *this;
}
inline bool operator==(StackAllocator const& /*other*/) const
{
return true;
}
inline bool operator!=(StackAllocator const& other) const
{
return !operator==(other);
}
private:
int pointer_;
bool use_stack_;
T data_[SIZE];
};
CCL_NAMESPACE_END
#endif /* __UTIL_GUARDED_ALLOCATOR_H__ */