EBGeometry::PoolLocation Struct Reference

Where a pool-resident descriptor resolves its offsets, and the rules for moving it. More...

#include <EBGeometry_Pool.hpp>

Collaboration diagram for EBGeometry::PoolLocation:

Public Member Functions
void *	base () const noexcept
	The base address the descriptor's offsets resolve against.
bool	isAttachedTo (const Pool &a_pool) const noexcept
	Whether this location follows the given pool.
void	attach (const Pool &a_pool, const char *a_who) noexcept
	Start following a pool, as the descriptor's first reservation from it does.
PoolLocation	rebasedOnto (const Pool &a_pool, uint64_t a_endByte, const char *a_who) const noexcept
	The location of the same arrays in another pool of the same mirror chain.

Public Attributes
const PoolControl *	m_control = nullptr
	Control block of the pool the descriptor follows; null for a snapshot or when unset.
void *	m_base = nullptr
	Base address captured by a snapshot; null otherwise.
bool	m_hostAccessible = false
	Whether host code may dereference a snapshot's base (managed or mapped memory).

Detailed Description

Where a pool-resident descriptor resolves its offsets, and the rules for moving it.

Every pool-resident handle (EBGeometry::DCEL::MeshT, EBGeometry::BVH::PackedBVH, and the classes built on them) holds one PoolLocation through its PoolHandle base, and delegates attaching, resolving and rebasing to it. It is in one of three states, decided by its value:

• Unset: nothing has been reserved yet.
• Following a pool: m_control is set. base() reads the pool's current base through the control block on every call, so a pool that grows and moves its block is invisible to the descriptor. Only host code can follow a pool.
• Snapshot: m_control is null and m_base holds the base of a frozen, device-accessible pool, captured by rebasedOnto(). This is what a kernel receives. If that memory is also host-accessible (managed or mapped memory), m_hostAccessible is set and host code may use the snapshot too.

A descriptor changes location only through rebasedView(), which calls rebasedOnto(). Only handles hold a location (see PoolHandle): a descriptor stored inside another object's pool – a TriMeshSDF held in the primitive array of a EBGeometry::BVHUnion, for instance – is stored as its layout, and the outer handle pairs it with its own location.

Member Function Documentation

attach()

void EBGeometry::PoolLocation::attach ( const Pool &  a_pool, const char *  a_who  )

inlinenoexcept

Start following a pool, as the descriptor's first reservation from it does.

Aborts, in every build, if the location already follows a different pool: all of a descriptor's arrays resolve against one base, so they must come from one pool.

Parameters

[in]	a_pool	Pool to follow.
[in]	a_who	Name of the descriptor class, for the message.

base()

void * EBGeometry::PoolLocation::base ( ) const

inlinenoexcept

The base address the descriptor's offsets resolve against.

On the host, the followed pool's current base, or a snapshot's base if host code may use it. On a device, the snapshot's base: a location that still follows a host pool means a host descriptor was copied into a kernel without rebasedView(), which EBGEOMETRY_EXPECT catches.

Returns

The base address.

isAttachedTo()

bool EBGeometry::PoolLocation::isAttachedTo ( const Pool &  a_pool ) const

inlinenoexcept

Whether this location follows the given pool.

Parameters

[in]

a_pool

Pool to compare with.

Returns

True if the descriptor follows a_pool's control block.

rebasedOnto()

PoolLocation EBGeometry::PoolLocation::rebasedOnto ( const Pool &  a_pool, uint64_t  a_endByte, const char *  a_who  ) const

inlinenoexcept

The location of the same arrays in another pool of the same mirror chain.

The descriptor must follow a pool (not be a snapshot or unset), a_pool must belong to the same mirror chain – the pool itself, one of its mirrors, or a mirror of a mirror – and the descriptor's arrays must fit inside it. Each is checked in every build. A device-accessible a_pool, which must be frozen so its base cannot move, gives a snapshot; a host pool gives a location that follows it.

Parameters

[in]	a_pool	Pool to resolve against.
[in]	a_endByte	First byte past the descriptor's last array.
[in]	a_who	Name of the descriptor class, for the messages.

Returns

The new location.

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The documentation for this struct was generated from the following file:

• Source/EBGeometry_Pool.hpp