Program Listing for File spirv_cross_containers.hpp
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/*
* Copyright 2019-2021 Hans-Kristian Arntzen
* SPDX-License-Identifier: Apache-2.0 OR MIT
*
* 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.
*/
/*
* At your option, you may choose to accept this material under either:
* 1. The Apache License, Version 2.0, found at <http://www.apache.org/licenses/LICENSE-2.0>, or
* 2. The MIT License, found at <http://opensource.org/licenses/MIT>.
*/
#ifndef SPIRV_CROSS_CONTAINERS_HPP
#define SPIRV_CROSS_CONTAINERS_HPP
#include "spirv_cross_error_handling.hpp"
#include <algorithm>
#include <exception>
#include <functional>
#include <iterator>
#include <limits>
#include <memory>
#include <stack>
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <type_traits>
#include <unordered_map>
#include <unordered_set>
#include <utility>
#include <vector>
#ifdef SPIRV_CROSS_NAMESPACE_OVERRIDE
#define SPIRV_CROSS_NAMESPACE SPIRV_CROSS_NAMESPACE_OVERRIDE
#else
#define SPIRV_CROSS_NAMESPACE spirv_cross
#endif
namespace SPIRV_CROSS_NAMESPACE
{
#ifndef SPIRV_CROSS_FORCE_STL_TYPES
// std::aligned_storage does not support size == 0, so roll our own.
template <typename T, size_t N>
class AlignedBuffer
{
public:
T *data()
{
#if defined(_MSC_VER) && _MSC_VER < 1900
// MSVC 2013 workarounds, sigh ...
// Only use this workaround on MSVC 2013 due to some confusion around default initialized unions.
// Spec seems to suggest the memory will be zero-initialized, which is *not* what we want.
return reinterpret_cast<T *>(u.aligned_char);
#else
return reinterpret_cast<T *>(aligned_char);
#endif
}
private:
#if defined(_MSC_VER) && _MSC_VER < 1900
// MSVC 2013 workarounds, sigh ...
union
{
char aligned_char[sizeof(T) * N];
double dummy_aligner;
} u;
#else
alignas(T) char aligned_char[sizeof(T) * N];
#endif
};
template <typename T>
class AlignedBuffer<T, 0>
{
public:
T *data()
{
return nullptr;
}
};
// An immutable version of SmallVector which erases type information about storage.
template <typename T>
class VectorView
{
public:
T &operator[](size_t i) SPIRV_CROSS_NOEXCEPT
{
return ptr[i];
}
const T &operator[](size_t i) const SPIRV_CROSS_NOEXCEPT
{
return ptr[i];
}
bool empty() const SPIRV_CROSS_NOEXCEPT
{
return buffer_size == 0;
}
size_t size() const SPIRV_CROSS_NOEXCEPT
{
return buffer_size;
}
T *data() SPIRV_CROSS_NOEXCEPT
{
return ptr;
}
const T *data() const SPIRV_CROSS_NOEXCEPT
{
return ptr;
}
T *begin() SPIRV_CROSS_NOEXCEPT
{
return ptr;
}
T *end() SPIRV_CROSS_NOEXCEPT
{
return ptr + buffer_size;
}
const T *begin() const SPIRV_CROSS_NOEXCEPT
{
return ptr;
}
const T *end() const SPIRV_CROSS_NOEXCEPT
{
return ptr + buffer_size;
}
T &front() SPIRV_CROSS_NOEXCEPT
{
return ptr[0];
}
const T &front() const SPIRV_CROSS_NOEXCEPT
{
return ptr[0];
}
T &back() SPIRV_CROSS_NOEXCEPT
{
return ptr[buffer_size - 1];
}
const T &back() const SPIRV_CROSS_NOEXCEPT
{
return ptr[buffer_size - 1];
}
// Makes it easier to consume SmallVector.
#if defined(_MSC_VER) && _MSC_VER < 1900
explicit operator std::vector<T>() const
{
// Another MSVC 2013 workaround. It does not understand lvalue/rvalue qualified operations.
return std::vector<T>(ptr, ptr + buffer_size);
}
#else
// Makes it easier to consume SmallVector.
explicit operator std::vector<T>() const &
{
return std::vector<T>(ptr, ptr + buffer_size);
}
// If we are converting as an r-value, we can pilfer our elements.
explicit operator std::vector<T>() &&
{
return std::vector<T>(std::make_move_iterator(ptr), std::make_move_iterator(ptr + buffer_size));
}
#endif
// Avoid sliced copies. Base class should only be read as a reference.
VectorView(const VectorView &) = delete;
void operator=(const VectorView &) = delete;
protected:
VectorView() = default;
T *ptr = nullptr;
size_t buffer_size = 0;
};
// Simple vector which supports up to N elements inline, without malloc/free.
// We use a lot of throwaway vectors all over the place which triggers allocations.
// This class only implements the subset of std::vector we need in SPIRV-Cross.
// It is *NOT* a drop-in replacement in general projects.
template <typename T, size_t N = 8>
class SmallVector : public VectorView<T>
{
public:
SmallVector() SPIRV_CROSS_NOEXCEPT
{
this->ptr = stack_storage.data();
buffer_capacity = N;
}
template <typename U>
SmallVector(const U *arg_list_begin, const U *arg_list_end) SPIRV_CROSS_NOEXCEPT : SmallVector()
{
auto count = size_t(arg_list_end - arg_list_begin);
reserve(count);
for (size_t i = 0; i < count; i++, arg_list_begin++)
new (&this->ptr[i]) T(*arg_list_begin);
this->buffer_size = count;
}
template <typename U>
SmallVector(std::initializer_list<U> init) SPIRV_CROSS_NOEXCEPT : SmallVector(init.begin(), init.end())
{
}
template <typename U, size_t M>
explicit SmallVector(const U (&init)[M]) SPIRV_CROSS_NOEXCEPT : SmallVector(init, init + M)
{
}
SmallVector(SmallVector &&other) SPIRV_CROSS_NOEXCEPT : SmallVector()
{
*this = std::move(other);
}
SmallVector &operator=(SmallVector &&other) SPIRV_CROSS_NOEXCEPT
{
clear();
if (other.ptr != other.stack_storage.data())
{
// Pilfer allocated pointer.
if (this->ptr != stack_storage.data())
free(this->ptr);
this->ptr = other.ptr;
this->buffer_size = other.buffer_size;
buffer_capacity = other.buffer_capacity;
other.ptr = nullptr;
other.buffer_size = 0;
other.buffer_capacity = 0;
}
else
{
// Need to move the stack contents individually.
reserve(other.buffer_size);
for (size_t i = 0; i < other.buffer_size; i++)
{
new (&this->ptr[i]) T(std::move(other.ptr[i]));
other.ptr[i].~T();
}
this->buffer_size = other.buffer_size;
other.buffer_size = 0;
}
return *this;
}
SmallVector(const SmallVector &other) SPIRV_CROSS_NOEXCEPT : SmallVector()
{
*this = other;
}
SmallVector &operator=(const SmallVector &other) SPIRV_CROSS_NOEXCEPT
{
if (this == &other)
return *this;
clear();
reserve(other.buffer_size);
for (size_t i = 0; i < other.buffer_size; i++)
new (&this->ptr[i]) T(other.ptr[i]);
this->buffer_size = other.buffer_size;
return *this;
}
explicit SmallVector(size_t count) SPIRV_CROSS_NOEXCEPT : SmallVector()
{
resize(count);
}
~SmallVector()
{
clear();
if (this->ptr != stack_storage.data())
free(this->ptr);
}
void clear() SPIRV_CROSS_NOEXCEPT
{
for (size_t i = 0; i < this->buffer_size; i++)
this->ptr[i].~T();
this->buffer_size = 0;
}
void push_back(const T &t) SPIRV_CROSS_NOEXCEPT
{
reserve(this->buffer_size + 1);
new (&this->ptr[this->buffer_size]) T(t);
this->buffer_size++;
}
void push_back(T &&t) SPIRV_CROSS_NOEXCEPT
{
reserve(this->buffer_size + 1);
new (&this->ptr[this->buffer_size]) T(std::move(t));
this->buffer_size++;
}
void pop_back() SPIRV_CROSS_NOEXCEPT
{
// Work around false positive warning on GCC 8.3.
// Calling pop_back on empty vector is undefined.
if (!this->empty())
resize(this->buffer_size - 1);
}
template <typename... Ts>
void emplace_back(Ts &&... ts) SPIRV_CROSS_NOEXCEPT
{
reserve(this->buffer_size + 1);
new (&this->ptr[this->buffer_size]) T(std::forward<Ts>(ts)...);
this->buffer_size++;
}
void reserve(size_t count) SPIRV_CROSS_NOEXCEPT
{
if ((count > (std::numeric_limits<size_t>::max)() / sizeof(T)) ||
(count > (std::numeric_limits<size_t>::max)() / 2))
{
// Only way this should ever happen is with garbage input, terminate.
std::terminate();
}
if (count > buffer_capacity)
{
size_t target_capacity = buffer_capacity;
if (target_capacity == 0)
target_capacity = 1;
// Weird parens works around macro issues on Windows if NOMINMAX is not used.
target_capacity = (std::max)(target_capacity, N);
// Need to ensure there is a POT value of target capacity which is larger than count,
// otherwise this will overflow.
while (target_capacity < count)
target_capacity <<= 1u;
T *new_buffer =
target_capacity > N ? static_cast<T *>(malloc(target_capacity * sizeof(T))) : stack_storage.data();
// If we actually fail this malloc, we are hosed anyways, there is no reason to attempt recovery.
if (!new_buffer)
std::terminate();
// In case for some reason two allocations both come from same stack.
if (new_buffer != this->ptr)
{
// We don't deal with types which can throw in move constructor.
for (size_t i = 0; i < this->buffer_size; i++)
{
new (&new_buffer[i]) T(std::move(this->ptr[i]));
this->ptr[i].~T();
}
}
if (this->ptr != stack_storage.data())
free(this->ptr);
this->ptr = new_buffer;
buffer_capacity = target_capacity;
}
}
void insert(T *itr, const T *insert_begin, const T *insert_end) SPIRV_CROSS_NOEXCEPT
{
auto count = size_t(insert_end - insert_begin);
if (itr == this->end())
{
reserve(this->buffer_size + count);
for (size_t i = 0; i < count; i++, insert_begin++)
new (&this->ptr[this->buffer_size + i]) T(*insert_begin);
this->buffer_size += count;
}
else
{
if (this->buffer_size + count > buffer_capacity)
{
auto target_capacity = this->buffer_size + count;
if (target_capacity == 0)
target_capacity = 1;
if (target_capacity < N)
target_capacity = N;
while (target_capacity < count)
target_capacity <<= 1u;
// Need to allocate new buffer. Move everything to a new buffer.
T *new_buffer =
target_capacity > N ? static_cast<T *>(malloc(target_capacity * sizeof(T))) : stack_storage.data();
// If we actually fail this malloc, we are hosed anyways, there is no reason to attempt recovery.
if (!new_buffer)
std::terminate();
// First, move elements from source buffer to new buffer.
// We don't deal with types which can throw in move constructor.
auto *target_itr = new_buffer;
auto *original_source_itr = this->begin();
if (new_buffer != this->ptr)
{
while (original_source_itr != itr)
{
new (target_itr) T(std::move(*original_source_itr));
original_source_itr->~T();
++original_source_itr;
++target_itr;
}
}
// Copy-construct new elements.
for (auto *source_itr = insert_begin; source_itr != insert_end; ++source_itr, ++target_itr)
new (target_itr) T(*source_itr);
// Move over the other half.
if (new_buffer != this->ptr || insert_begin != insert_end)
{
while (original_source_itr != this->end())
{
new (target_itr) T(std::move(*original_source_itr));
original_source_itr->~T();
++original_source_itr;
++target_itr;
}
}
if (this->ptr != stack_storage.data())
free(this->ptr);
this->ptr = new_buffer;
buffer_capacity = target_capacity;
}
else
{
// Move in place, need to be a bit careful about which elements are constructed and which are not.
// Move the end and construct the new elements.
auto *target_itr = this->end() + count;
auto *source_itr = this->end();
while (target_itr != this->end() && source_itr != itr)
{
--target_itr;
--source_itr;
new (target_itr) T(std::move(*source_itr));
}
// For already constructed elements we can move-assign.
std::move_backward(itr, source_itr, target_itr);
// For the inserts which go to already constructed elements, we can do a plain copy.
while (itr != this->end() && insert_begin != insert_end)
*itr++ = *insert_begin++;
// For inserts into newly allocated memory, we must copy-construct instead.
while (insert_begin != insert_end)
{
new (itr) T(*insert_begin);
++itr;
++insert_begin;
}
}
this->buffer_size += count;
}
}
void insert(T *itr, const T &value) SPIRV_CROSS_NOEXCEPT
{
insert(itr, &value, &value + 1);
}
T *erase(T *itr) SPIRV_CROSS_NOEXCEPT
{
std::move(itr + 1, this->end(), itr);
this->ptr[--this->buffer_size].~T();
return itr;
}
void erase(T *start_erase, T *end_erase) SPIRV_CROSS_NOEXCEPT
{
if (end_erase == this->end())
{
resize(size_t(start_erase - this->begin()));
}
else
{
auto new_size = this->buffer_size - (end_erase - start_erase);
std::move(end_erase, this->end(), start_erase);
resize(new_size);
}
}
void resize(size_t new_size) SPIRV_CROSS_NOEXCEPT
{
if (new_size < this->buffer_size)
{
for (size_t i = new_size; i < this->buffer_size; i++)
this->ptr[i].~T();
}
else if (new_size > this->buffer_size)
{
reserve(new_size);
for (size_t i = this->buffer_size; i < new_size; i++)
new (&this->ptr[i]) T();
}
this->buffer_size = new_size;
}
private:
size_t buffer_capacity = 0;
AlignedBuffer<T, N> stack_storage;
};
// A vector without stack storage.
// Could also be a typedef-ed to std::vector,
// but might as well use the one we have.
template <typename T>
using Vector = SmallVector<T, 0>;
#else // SPIRV_CROSS_FORCE_STL_TYPES
template <typename T, size_t N = 8>
using SmallVector = std::vector<T>;
template <typename T>
using Vector = std::vector<T>;
template <typename T>
using VectorView = std::vector<T>;
#endif // SPIRV_CROSS_FORCE_STL_TYPES
// An object pool which we use for allocating IVariant-derived objects.
// We know we are going to allocate a bunch of objects of each type,
// so amortize the mallocs.
class ObjectPoolBase
{
public:
virtual ~ObjectPoolBase() = default;
virtual void deallocate_opaque(void *ptr) = 0;
};
template <typename T>
class ObjectPool : public ObjectPoolBase
{
public:
explicit ObjectPool(unsigned start_object_count_ = 16)
: start_object_count(start_object_count_)
{
}
template <typename... P>
T *allocate(P &&... p)
{
if (vacants.empty())
{
unsigned num_objects = start_object_count << memory.size();
T *ptr = static_cast<T *>(malloc(num_objects * sizeof(T)));
if (!ptr)
return nullptr;
for (unsigned i = 0; i < num_objects; i++)
vacants.push_back(&ptr[i]);
memory.emplace_back(ptr);
}
T *ptr = vacants.back();
vacants.pop_back();
new (ptr) T(std::forward<P>(p)...);
return ptr;
}
void deallocate(T *ptr)
{
ptr->~T();
vacants.push_back(ptr);
}
void deallocate_opaque(void *ptr) override
{
deallocate(static_cast<T *>(ptr));
}
void clear()
{
vacants.clear();
memory.clear();
}
protected:
Vector<T *> vacants;
struct MallocDeleter
{
void operator()(T *ptr)
{
::free(ptr);
}
};
SmallVector<std::unique_ptr<T, MallocDeleter>> memory;
unsigned start_object_count;
};
template <size_t StackSize = 4096, size_t BlockSize = 4096>
class StringStream
{
public:
StringStream()
{
reset();
}
~StringStream()
{
reset();
}
// Disable copies and moves. Makes it easier to implement, and we don't need it.
StringStream(const StringStream &) = delete;
void operator=(const StringStream &) = delete;
template <typename T, typename std::enable_if<!std::is_floating_point<T>::value, int>::type = 0>
StringStream &operator<<(const T &t)
{
auto s = std::to_string(t);
append(s.data(), s.size());
return *this;
}
// Only overload this to make float/double conversions ambiguous.
StringStream &operator<<(uint32_t v)
{
auto s = std::to_string(v);
append(s.data(), s.size());
return *this;
}
StringStream &operator<<(char c)
{
append(&c, 1);
return *this;
}
StringStream &operator<<(const std::string &s)
{
append(s.data(), s.size());
return *this;
}
StringStream &operator<<(const char *s)
{
append(s, strlen(s));
return *this;
}
template <size_t N>
StringStream &operator<<(const char (&s)[N])
{
append(s, strlen(s));
return *this;
}
std::string str() const
{
std::string ret;
size_t target_size = 0;
for (auto &saved : saved_buffers)
target_size += saved.offset;
target_size += current_buffer.offset;
ret.reserve(target_size);
for (auto &saved : saved_buffers)
ret.insert(ret.end(), saved.buffer, saved.buffer + saved.offset);
ret.insert(ret.end(), current_buffer.buffer, current_buffer.buffer + current_buffer.offset);
return ret;
}
void reset()
{
for (auto &saved : saved_buffers)
if (saved.buffer != stack_buffer)
free(saved.buffer);
if (current_buffer.buffer != stack_buffer)
free(current_buffer.buffer);
saved_buffers.clear();
current_buffer.buffer = stack_buffer;
current_buffer.offset = 0;
current_buffer.size = sizeof(stack_buffer);
}
private:
struct Buffer
{
char *buffer = nullptr;
size_t offset = 0;
size_t size = 0;
};
Buffer current_buffer;
char stack_buffer[StackSize];
SmallVector<Buffer> saved_buffers;
void append(const char *s, size_t len)
{
size_t avail = current_buffer.size - current_buffer.offset;
if (avail < len)
{
if (avail > 0)
{
memcpy(current_buffer.buffer + current_buffer.offset, s, avail);
s += avail;
len -= avail;
current_buffer.offset += avail;
}
saved_buffers.push_back(current_buffer);
size_t target_size = len > BlockSize ? len : BlockSize;
current_buffer.buffer = static_cast<char *>(malloc(target_size));
if (!current_buffer.buffer)
SPIRV_CROSS_THROW("Out of memory.");
memcpy(current_buffer.buffer, s, len);
current_buffer.offset = len;
current_buffer.size = target_size;
}
else
{
memcpy(current_buffer.buffer + current_buffer.offset, s, len);
current_buffer.offset += len;
}
}
};
} // namespace SPIRV_CROSS_NAMESPACE
#endif