Classes
struct	AllocatorStats
	Runtime statistics snapshot for PMR allocators. More...
class	ArcFromThis
	CRTP base class that embeds an atomic reference counter into the derived type. More...
class	ArenaAllocator
	PMR arena allocator with lock-free hot allocation path. More...
struct	ArenaOptions
	Configuration for ArenaAllocator. More...
class	AtomicRefCounted
	Thread-safe intrusive reference-counted smart pointer. More...
class	FixedArenaAllocator
	PMR arena with fixed runtime capacity. More...
class	FixedFreeListAllocator
	Fixed-capacity best-fit allocator with coalescing. More...
class	FixedPoolAllocator
	Fixed-capacity intrusive block pool. More...
struct	FixedPoolAllocatorOptions
	Configuration for FixedPoolAllocator. More...
class	FixedStackAllocator
	PMR stack allocator with fixed runtime capacity. More...
class	FrameAllocator
	N-buffered PMR frame allocator. More...
struct	FrameAllocatorOptions
	Configuration for FrameAllocator. More...
class	FreeListAllocator
	General-purpose PMR free-list allocator. More...
struct	FreeListAllocatorOptions
	Configuration for FreeListAllocator. More...
struct	GrowthPolicy
	Capacity growth configuration. More...
class	PoolAllocator
	Lock-free PMR pool allocator for fixed-size blocks. More...
struct	PoolAllocatorOptions
	Configuration for PoolAllocator. More...
class	RcFromThis
	CRTP base class that embeds a non-atomic reference counter into the derived type. More...
class	RefCounted
	Non-atomic intrusive reference-counted smart pointer. More...
class	StackAllocator
	PMR stack allocator with LIFO-aware deallocation. More...
struct	StackAllocatorOptions
	Configuration for StackAllocator. More...

Concepts
concept	PmrAllocator
	Concept for PMR resources used by the memory module.
concept	PmrAllocatorWithStats
	Concept for PMR resources that expose allocator statistics.
concept	ResettablePmrAllocator
	Concept for PMR resources that support reset.

Typedefs
template<typename T, typename Allocator = std::allocator<T>>
using	Rc = RefCounted<T, Allocator>
	Alias for RefCounted<T> — non-atomic intrusive reference-counted handle.
template<typename T, typename Allocator = std::allocator<T>>
using	Arc = AtomicRefCounted<T, Allocator>
	Alias for AtomicRefCounted<T> — thread-safe intrusive reference-counted handle.
template<typename T>
using	PmrRc = RefCounted<T, std::pmr::polymorphic_allocator<T>>
	Alias for RefCounted<T> using polymorphic memory allocator.
template<typename T>
using	PmrArc = AtomicRefCounted<T, std::pmr::polymorphic_allocator<T>>
	Alias for AtomicRefCounted<T> using polymorphic memory allocator.

Enumerations
enum class	GrowthMode : uint8_t { kLinear , kGeometric }
	Growth strategy used by growable allocators. More...
enum class	MemoryError : uint8_t { kOutOfMemory , kInvalidAlignment , kInvalidSize , kGrowthDisabled , kOwnershipMismatch }
	Error codes used for explicit non-fatal memory operations. More...

Functions
void *	AlignedAlloc (size_t alignment, size_t size, bool enable_profile=true) noexcept
	Allocates memory with the specified alignment.
void	AlignedFree (void *ptr, bool enable_profile=true) noexcept
	Frees memory allocated with AlignedAlloc.
template<typename T, PmrAllocator Alloc>
auto	TryAllocate (Alloc &allocator) noexcept -> std::expected< T *, MemoryError >
	Tries to allocate one object from a PMR allocator.
template<typename T, PmrAllocator Alloc>
auto	TryAllocateSpan (Alloc &allocator, size_t count) noexcept -> std::expected< std::span< T >, MemoryError >
	Tries to allocate an array of objects from a PMR allocator.
template<typename T, PmrAllocator Alloc>
void	Deallocate (Alloc &allocator, T *ptr) noexcept
	Deallocates an object allocated by TryAllocate.
template<typename T, PmrAllocator Alloc>
void	Deallocate (Alloc &allocator, std::span< T > span) noexcept
	Deallocates an array allocated by TryAllocateSpan.
template<PmrAllocator Alloc>
constexpr AllocatorStats	Stats (const Alloc &allocator) noexcept
	Adapts stats-aware PMR resources.
constexpr size_t	SaturatingAdd (size_t lhs, size_t rhs) noexcept
	Saturating add for size_t.
constexpr size_t	SaturatingMul (size_t lhs, size_t rhs) noexcept
	Saturating multiply for size_t.
constexpr std::string_view	MemoryErrorToString (MemoryError error) noexcept
	Converts MemoryError to a readable string.
constexpr bool	IsPowerOfTwo (size_t value) noexcept
	Checks if a value is a power of two.
constexpr size_t	AlignUp (size_t value, size_t alignment) noexcept
	Aligns value up to alignment.
void *	AlignUpPtr (void *ptr, size_t alignment) noexcept
	Aligns pointer up to alignment.
bool	IsAligned (const void *ptr, size_t alignment) noexcept
	Checks if pointer is aligned.
size_t	CalculatePadding (const void *ptr, size_t alignment) noexcept
	Computes padding required for pointer alignment.
size_t	CalculatePaddingWithHeader (const void *ptr, size_t alignment, size_t header_size) noexcept
	Computes padding for aligned storage with a prepended header.
template<typename T, typename... Args> requires std::derived_from<T, RcFromThis<T>> && std::constructible_from<T, Args...>
auto	MakeRc (Args &&... args) -> Rc< T >
	Allocates and constructs a T object, returning a Rc<T, std::allocator<T>> handle.
template<typename T, typename... Args> requires std::derived_from<T, ArcFromThis<T>> && std::constructible_from<T, Args...>
auto	MakeArc (Args &&... args) -> Arc< T >
	Allocates and constructs a T object, returning an Arc<T, std::allocator<T>> handle.
template<typename T, typename Allocator, typename... Args> requires std::derived_from<T, RcFromThis<T>> && std::constructible_from<T, Args...> && (!std::derived_from<std::remove_pointer_t <Allocator>, std::pmr::memory_resource>)
auto	MakeRcWith (Allocator alloc, Args &&... args) -> Rc< T, Allocator >
	Overload of MakeRc accepting a pre-constructed allocator instance.
template<typename T, typename... Args> requires std::derived_from<T, RcFromThis<T>> && std::constructible_from<T, Args...>
auto	MakeRcWith (std::pmr::memory_resource *resource, Args &&... args) -> PmrRc< T >
	Allocates and constructs a T object using PMR memory resource, returning a PmrRc<T> handle.
template<typename T, typename... Args>
auto	MakeRcWith (std::nullptr_t, Args &&...) -> PmrRc< T >=delete
template<typename T, typename Allocator, typename... Args> requires std::derived_from<T, ArcFromThis<T>> && std::constructible_from<T, Args...> && (!std::derived_from<std::remove_pointer_t <Allocator>, std::pmr::memory_resource>)
auto	MakeArcWith (Allocator alloc, Args &&... args) -> Arc< T, Allocator >
	Overload of MakeArc accepting a pre-constructed allocator instance.
template<typename T, typename... Args> requires std::derived_from<T, ArcFromThis<T>> && std::constructible_from<T, Args...>
auto	MakeArcWith (std::pmr::memory_resource *resource, Args &&... args) -> PmrArc< T >
	Allocates and constructs a T object using PMR memory resource, returning a PmrArc<T> handle.
template<typename T, typename... Args>
auto	MakeArcWith (std::nullptr_t, Args &&...) -> PmrArc< T >=delete

Variables
constexpr size_t	kDefaultAlignment = 64
	Default alignment used by memory resources.
constexpr size_t	kMinAlignment = alignof(std::max_align_t)
	Minimum alignment used by memory resources.

Typedef Documentation

◆ Arc

template<typename T, typename Allocator = std::allocator<T>>

using helios::mem::Arc = AtomicRefCounted<T, Allocator>

Alias for AtomicRefCounted<T> — thread-safe intrusive reference-counted handle.

Definition at line 1139 of file ref_counted.hpp.

◆ PmrArc

template<typename T>

using helios::mem::PmrArc = AtomicRefCounted<T, std::pmr::polymorphic_allocator<T>>

Alias for AtomicRefCounted<T> using polymorphic memory allocator.

Thread-safe intrusive reference-counted handle with PMR support.

Definition at line 1154 of file ref_counted.hpp.

◆ PmrRc

template<typename T>

using helios::mem::PmrRc = RefCounted<T, std::pmr::polymorphic_allocator<T>>

Alias for RefCounted<T> using polymorphic memory allocator.

Allows using std::pmr::memory_resource for dynamic allocator selection.

Definition at line 1147 of file ref_counted.hpp.

◆ Rc

template<typename T, typename Allocator = std::allocator<T>>

using helios::mem::Rc = RefCounted<T, Allocator>

Alias for RefCounted<T> — non-atomic intrusive reference-counted handle.

Definition at line 1134 of file ref_counted.hpp.

Enumeration Type Documentation

◆ GrowthMode

enum class helios::mem::GrowthMode : uint8_t

strong

Growth strategy used by growable allocators.

Enumerator
kLinear	Adds a fixed byte step on each growth request.
kGeometric	Multiplies capacity by a configured ratio on growth.

Definition at line 51 of file common.hpp.

◆ MemoryError

enum class helios::mem::MemoryError : uint8_t

strong

Error codes used for explicit non-fatal memory operations.

Enumerator
kOutOfMemory	Allocation request could not be satisfied.
kInvalidAlignment	Requested alignment is not supported.
kInvalidSize	Requested size is zero or overflows.
kGrowthDisabled	Growable allocator cannot expand further.
kOwnershipMismatch	Pointer does not belong to the allocator.

Definition at line 179 of file common.hpp.

Function Documentation

◆ AlignedAlloc()

void * helios::mem::AlignedAlloc	(	size_t	alignment,
		size_t	size,
		bool	enable_profile = true )

nodiscardnoexcept

Allocates memory with the specified alignment.

Uses mimalloc when enabled, _aligned_malloc on MSVC, and std::aligned_alloc on other platforms. On POSIX, std::aligned_alloc requires alignment >= sizeof(void*). Smaller alignments are satisfied via malloc, which provides at least alignof(std::max_align_t) alignment.

Warning: Triggers assertion when alignment is zero, alignment is not a power of two, or size is zero.

Parameters

alignment	The alignment in bytes (must be a power of two and non-zero)
size	The size of the memory block to allocate in bytes (must be non-zero)
enable_profile	When false, skips profiler memory events (for internal allocator backing storage that is tracked separately)

Returns: A pointer to the allocated memory block, or nullptr on failure

Definition at line 18 of file aligned_alloc.cpp.

◆ AlignedFree()

void helios::mem::AlignedFree	(	void *	ptr,
		bool	enable_profile = true )

noexcept

Frees memory allocated with AlignedAlloc.

Uses the allocation backend paired with AlignedAlloc. Passing nullptr is a no-op.

Parameters

ptr	The pointer to the memory block to free
enable_profile	When false, skips profiler memory events

Definition at line 45 of file aligned_alloc.cpp.

◆ AlignUp()

size_t helios::mem::AlignUp	(	size_t	value,
		size_t	alignment )

nodiscardconstexprnoexcept

Aligns value up to alignment.

Warning: Triggers assertion when alignment is not a power of two.

Parameters

value	Value to align
alignment	Alignment, must be a power of two

Returns: Aligned value

Definition at line 226 of file common.hpp.

◆ AlignUpPtr()

void * helios::mem::AlignUpPtr	(	void *	ptr,
		size_t	alignment )

inlinenodiscardnoexcept

Aligns pointer up to alignment.

Warning: Triggers assertion when alignment is not a power of two.

Parameters

ptr	Pointer to align
alignment	Alignment, must be a power of two

Returns: Aligned pointer

Definition at line 244 of file common.hpp.

◆ CalculatePadding()

size_t helios::mem::CalculatePadding	(	const void *	ptr,
		size_t	alignment )

inlinenodiscardnoexcept

Computes padding required for pointer alignment.

Parameters

ptr	Current pointer
alignment	Requested alignment

Returns: Padding in bytes

Definition at line 274 of file common.hpp.

◆ CalculatePaddingWithHeader()

size_t helios::mem::CalculatePaddingWithHeader	(	const void *	ptr,
		size_t	alignment,
		size_t	header_size )

inlinenodiscardnoexcept

Computes padding for aligned storage with a prepended header.

Parameters

ptr	Current pointer
alignment	Requested alignment
header_size	Header size stored before aligned user memory

Returns: Padding in bytes, including header space

Definition at line 288 of file common.hpp.

◆ Deallocate() [1/2]

template<typename T, PmrAllocator Alloc>

void helios::mem::Deallocate	(	Alloc &	allocator,
		std::span< T >	span )

inlinenoexcept

Deallocates an array allocated by TryAllocateSpan.

Template Parameters

T	Element type
Alloc	Allocator type

Parameters

allocator	Allocator reference
span	Span returned by TryAllocateSpan

Definition at line 124 of file allocator_traits.hpp.

◆ Deallocate() [2/2]

template<typename T, PmrAllocator Alloc>

void helios::mem::Deallocate	(	Alloc &	allocator,
		T *	ptr )

inlinenoexcept

Deallocates an object allocated by TryAllocate.

Template Parameters

T	Object type
Alloc	Allocator type

Parameters

allocator	Allocator reference
ptr	Pointer returned by TryAllocate

Definition at line 107 of file allocator_traits.hpp.

◆ IsAligned()

bool helios::mem::IsAligned	(	const void *	ptr,
		size_t	alignment )

inlinenodiscardnoexcept

Checks if pointer is aligned.

Warning: Triggers assertion when alignment is not a power of two.

Parameters

ptr	Pointer value
alignment	Alignment to check

Returns: True if pointer is aligned

Definition at line 260 of file common.hpp.

◆ IsPowerOfTwo()

bool helios::mem::IsPowerOfTwo ( size_t value )

nodiscardconstexprnoexcept

Checks if a value is a power of two.

Parameters

value Value to check

Returns: True if value is a power of two

Definition at line 215 of file common.hpp.

◆ MakeArc()

template<typename T, typename... Args>
requires std::derived_from<T, ArcFromThis<T>> && std::constructible_from<T, Args...>

auto helios::mem::MakeArc ( Args &&... args ) -> Arc< T >

inlinenodiscard

Allocates and constructs a T object, returning an Arc<T, std::allocator<T>> handle.

Preferred way to create AtomicRefCounted objects. The object is allocated via std::allocator<T> and owned by the returned handle.

Note: Only available when std::allocator<T> is default-constructible (it always is). For stateful allocators (e.g. arena, pool), use MakeArcWith instead.

Template Parameters

T	Type to construct; must inherit ArcFromThis<T>
Args	Constructor argument types

Parameters

args	Arguments forwarded to T's constructor

Returns: A new Arc<T> with ref count 1

auto tex = helios::mem::MakeArc<Texture>("diffuse");

helios::mem::MakeArc

auto MakeArc(Args &&... args) -> Arc< T >

Allocates and constructs a T object, returning an Arc<T, std::allocator<T>> handle.

Definition ref_counted.hpp:1204

Definition at line 1204 of file ref_counted.hpp.

◆ MakeArcWith() [1/3]

template<typename T, typename Allocator, typename... Args>
requires std::derived_from<T, ArcFromThis<T>> && std::constructible_from<T, Args...> && (!std::derived_from<std::remove_pointer_t
<Allocator>, std::pmr::memory_resource>)

auto helios::mem::MakeArcWith	(	Allocator	alloc,
		Args &&...	args ) -> Arc< T, Allocator >

inlinenodiscard

Overload of MakeArc accepting a pre-constructed allocator instance.

Use this when your allocator is stateful and must be initialised before the object is created (e.g. a PMR arena).

Template Parameters

T	Type to construct; must inherit ArcFromThis<T>
Allocator	Concrete allocator type (e.g. MyAllocator<T>)
Args	Constructor argument types

Parameters

alloc	Allocator instance to use
args	Arguments forwarded to T's constructor

Returns: A new Arc<T, Allocator> with ref count 1

Definition at line 1281 of file ref_counted.hpp.

◆ MakeArcWith() [2/3]

template<typename T, typename... Args>

auto helios::mem::MakeArcWith	(	std::nullptr_t	,
		Args &&	... ) -> PmrArc< T >=delete

delete

◆ MakeArcWith() [3/3]

template<typename T, typename... Args>
requires std::derived_from<T, ArcFromThis<T>> && std::constructible_from<T, Args...>

auto helios::mem::MakeArcWith	(	std::pmr::memory_resource *	resource,
		Args &&...	args ) -> PmrArc< T >

inlinenodiscard

Allocates and constructs a T object using PMR memory resource, returning a PmrArc<T> handle.

Convenience overload that wraps std::pmr::memory_resource* in a std::pmr::polymorphic_allocator<T>.

Template Parameters

T	Type to construct; must inherit ArcFromThis<T>
Args	Constructor argument types

Parameters

resource	PMR memory resource to use for allocation
args	Arguments forwarded to T's constructor

Returns: A new PmrArc<T> with ref count 1

auto tex = helios::mem::MakeArcWith<Texture>(pmr_resource, "diffuse");

helios::mem::MakeArcWith

auto MakeArcWith(Allocator alloc, Args &&... args) -> Arc< T, Allocator >

Overload of MakeArc accepting a pre-constructed allocator instance.

Definition ref_counted.hpp:1281

Definition at line 1307 of file ref_counted.hpp.

◆ MakeRc()

template<typename T, typename... Args>
requires std::derived_from<T, RcFromThis<T>> && std::constructible_from<T, Args...>

auto helios::mem::MakeRc ( Args &&... args ) -> Rc< T >

inlinenodiscard

Allocates and constructs a T object, returning a Rc<T, std::allocator<T>> handle.

Preferred way to create RefCounted objects. The object is allocated via std::allocator<T> and owned by the returned handle.

Template Parameters

T	Type to construct; must inherit RcFromThis<T>
Args	Constructor argument types

Parameters

args	Arguments forwarded to T's constructor

Returns: A new Rc<T> with ref count 1

auto mesh = helios::mem::MakeRc<Mesh>(42);

helios::mem::MakeRc

auto MakeRc(Args &&... args) -> Rc< T >

Allocates and constructs a T object, returning a Rc<T, std::allocator<T>> handle.

Definition ref_counted.hpp:1174

Definition at line 1174 of file ref_counted.hpp.

◆ MakeRcWith() [1/3]

template<typename T, typename Allocator, typename... Args>
requires std::derived_from<T, RcFromThis<T>> && std::constructible_from<T, Args...> && (!std::derived_from<std::remove_pointer_t
<Allocator>, std::pmr::memory_resource>)

auto helios::mem::MakeRcWith	(	Allocator	alloc,
		Args &&...	args ) -> Rc< T, Allocator >

inlinenodiscard

Overload of MakeRc accepting a pre-constructed allocator instance.

Use this when your allocator is stateful and must be initialised before the object is created (e.g. a PMR arena).

Template Parameters

T	Type to construct; must inherit RcFromThis<T>
Allocator	Concrete allocator type (e.g. MyAllocator<T>)
Args	Constructor argument types

Parameters

alloc	Allocator instance to use
args	Arguments forwarded to T's constructor

Returns: A new Rc<T, Allocator> with ref count 1

Definition at line 1229 of file ref_counted.hpp.

◆ MakeRcWith() [2/3]

template<typename T, typename... Args>

auto helios::mem::MakeRcWith	(	std::nullptr_t	,
		Args &&	... ) -> PmrRc< T >=delete

delete

◆ MakeRcWith() [3/3]

template<typename T, typename... Args>
requires std::derived_from<T, RcFromThis<T>> && std::constructible_from<T, Args...>

auto helios::mem::MakeRcWith	(	std::pmr::memory_resource *	resource,
		Args &&...	args ) -> PmrRc< T >

inlinenodiscard

Allocates and constructs a T object using PMR memory resource, returning a PmrRc<T> handle.

Convenience overload that wraps std::pmr::memory_resource* in a std::pmr::polymorphic_allocator<T>.

Template Parameters

T	Type to construct; must inherit RcFromThis<T>
Args	Constructor argument types

Parameters

resource	PMR memory resource to use for allocation
args	Arguments forwarded to T's constructor

Returns: A new PmrRc<T> with ref count 1

auto mesh = helios::mem::MakeRcWith<Mesh>(pmr_resource, 42);

helios::mem::MakeRcWith

auto MakeRcWith(Allocator alloc, Args &&... args) -> Rc< T, Allocator >

Overload of MakeRc accepting a pre-constructed allocator instance.

Definition ref_counted.hpp:1229

Definition at line 1255 of file ref_counted.hpp.

◆ MemoryErrorToString()

std::string_view helios::mem::MemoryErrorToString ( MemoryError error )

nodiscardconstexprnoexcept

Converts MemoryError to a readable string.

Parameters

error Error value

Returns: String view with the error description

Definition at line 192 of file common.hpp.

◆ SaturatingAdd()

size_t helios::mem::SaturatingAdd	(	size_t	lhs,
		size_t	rhs )

nodiscardconstexprnoexcept

Saturating add for size_t.

Parameters

lhs	Left operand
rhs	Right operand

Returns: lhs + rhs, clamped to size_t max on overflow

Definition at line 25 of file common.hpp.

◆ SaturatingMul()

size_t helios::mem::SaturatingMul	(	size_t	lhs,
		size_t	rhs )

nodiscardconstexprnoexcept

Saturating multiply for size_t.

Parameters

lhs	Left operand
rhs	Right operand

Returns: lhs * rhs, clamped to size_t max on overflow

Definition at line 39 of file common.hpp.

◆ Stats()

template<PmrAllocator Alloc>

AllocatorStats helios::mem::Stats ( const Alloc & allocator )

nodiscardconstexprnoexcept

Adapts stats-aware PMR resources.

Template Parameters

Alloc Allocator type

Parameters

allocator Allocator reference

Returns: Stats if available, otherwise zero-initialized stats

Definition at line 140 of file allocator_traits.hpp.

◆ TryAllocate()

template<typename T, PmrAllocator Alloc>

auto helios::mem::TryAllocate ( Alloc & allocator ) -> std::expected< T *, MemoryError >

inlinenodiscardnoexcept

Tries to allocate one object from a PMR allocator.

Template Parameters

T	Object type
Alloc	Allocator type

Parameters

allocator Allocator reference

Returns: Pointer to allocated object memory, or MemoryError

Definition at line 48 of file allocator_traits.hpp.

◆ TryAllocateSpan()

template<typename T, PmrAllocator Alloc>

auto helios::mem::TryAllocateSpan	(	Alloc &	allocator,
		size_t	count ) -> std::expected< std::span< T >, MemoryError >

inlinenodiscardnoexcept

Tries to allocate an array of objects from a PMR allocator.

Template Parameters

T	Element type
Alloc	Allocator type

Parameters

allocator	Allocator reference
count	Number of elements

Returns: Span over allocated memory, or MemoryError

Definition at line 76 of file allocator_traits.hpp.

Variable Documentation

◆ kDefaultAlignment

size_t helios::mem::kDefaultAlignment = 64

inlineconstexpr

Default alignment used by memory resources.

Definition at line 14 of file common.hpp.

◆ kMinAlignment

size_t helios::mem::kMinAlignment = alignof(std::max_align_t)

inlineconstexpr

Minimum alignment used by memory resources.

Definition at line 17 of file common.hpp.

Classes

Concepts

Typedefs

Enumerations

Functions

Variables

Typedef Documentation

◆ Arc

◆ PmrArc

◆ PmrRc

◆ Rc

Enumeration Type Documentation

◆ GrowthMode

◆ MemoryError

Function Documentation

◆ AlignedAlloc()

◆ AlignedFree()

◆ AlignUp()

◆ AlignUpPtr()

◆ CalculatePadding()

◆ CalculatePaddingWithHeader()

◆ Deallocate() [1/2]

◆ Deallocate() [2/2]

◆ IsAligned()

◆ IsPowerOfTwo()

◆ MakeArc()

◆ MakeArcWith() [1/3]

◆ MakeArcWith() [2/3]

◆ MakeArcWith() [3/3]

◆ MakeRc()

◆ MakeRcWith() [1/3]

◆ MakeRcWith() [2/3]

◆ MakeRcWith() [3/3]

◆ MemoryErrorToString()

◆ SaturatingAdd()

◆ SaturatingMul()

◆ Stats()

◆ TryAllocate()

◆ TryAllocateSpan()

Variable Documentation

◆ kDefaultAlignment

◆ kMinAlignment