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xo-ordinaltree: expand unittest + debug logging

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This commit is contained in:
Roland Conybeare 2025-12-05 18:38:29 -05:00
commit 39a9dc725c
3 changed files with 92 additions and 30 deletions
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32
include/xo/allocutil/IAlloc.hpp
View file

@ -143,8 +143,8 @@ namespace xo {
/** check write barrier (if impl has write barrier)
* given an object @p parent that contains object pointer @p lhs.
**/
virtual bool check_write_barrier(IObject * /*parent*/,
IObject ** /*lhs*/,
virtual bool check_write_barrier(const void * /*parent*/,
const void * const * /*lhs*/,
bool /*may_throw*/) const { return true; };
/** write barrier for collector. perform assignment
* @code
@ -169,6 +169,16 @@ namespace xo {
}
};
/** for gc_allocator_traits, want an allocator pointer we can inherit from **/
struct IAllocPtr {
public:
inline bool check_write_barrier(const void * parent, const void * const * lhs, bool may_throw) const {
return mm_->check_write_barrier(parent, lhs, may_throw);
}
IAlloc * mm_ = nullptr;
};
/** allocator wrapper (in the style of std::allocator)
**/
template <typename T>
@ -183,10 +193,11 @@ namespace xo {
using difference_type = std::ptrdiff_t;
using gc_object_interface = IAlloc::gc_object_interface;
using gc_interface = IAllocPtr;
using has_incremental_gc_interface = IAlloc::has_incremental_gc_interface;
/** rebind is for typed allocators. since IAlloc is untyped,
* we want degenerate version
* rebind is almost trivial
**/
template <typename U>
struct rebind {
@ -194,16 +205,16 @@ namespace xo {
};
public:
explicit allocator(IAlloc * mm) : mm_{mm} {}
explicit allocator(IAlloc * mm) : impl_{mm} {}
allocator(const allocator &) = default;
allocator & operator=(const allocator &) = default;
template <typename U>
allocator(const allocator<U> & other) : mm_{other.mm_} {}
allocator(const allocator<U> & other) : impl_{other.impl_.mm_} {}
pointer allocate(size_type n) {
std::byte * raw = mm_->allocate(n * sizeof(T));
std::byte * raw = impl_.mm_->allocate(n * sizeof(T));
return reinterpret_cast<pointer>(raw);
}
@ -211,7 +222,7 @@ namespace xo {
void deallocate(pointer p, size_type n) {
std::byte * raw = reinterpret_cast<std::byte *>(p);
mm_->deallocate(raw, n * sizeof(T));
impl_.mm_->deallocate(raw, n * sizeof(T));
}
// optional construct, destroy (but allocator_traits provides defaults)
@ -221,11 +232,14 @@ namespace xo {
**/
template <typename U>
bool operator==(const allocator<U> & other) const noexcept {
return mm_ == other.mm_;
return impl_.mm_ == other.impl_.mm_;
}
/** gc_interface=IAlloc **/
operator gc_interface () const { return impl_; }
public:
IAlloc * mm_ = nullptr;
IAllocPtr impl_;
};
} /*namespace gc*/

4
include/xo/allocutil/IObject.hpp
View file

@ -29,6 +29,8 @@ namespace xo {
/** GC write barrier:
* assign value @p rhs to member @p *lhs of @p parent.
* Identifiy and remember cross-generational pointers.
*
* Expect Allocator is xo::gc::allocator<T> (see IAlloc.hpp)
**/
template <typename T, typename Allocator>
void _gc_assign_member(T ** lhs,
@ -37,7 +39,7 @@ namespace xo {
{
static_assert(std::is_convertible_v<decltype(*lhs), IObject*>);
alloc.mm_->assign_member(this, reinterpret_cast<IObject **>(lhs), rhs);
alloc.impl_.mm_->assign_member(this, reinterpret_cast<IObject **>(lhs), rhs);
}
/** true iff this object represents a forwarding pointer.

86
include/xo/allocutil/gc_allocator_traits.hpp
View file

@ -40,6 +40,19 @@ namespace xo {
virtual std::size_t _forward_children(gc::IAlloc *) { assert(false); return 0; }
};
/** dummy GC interface.
* non-empty intersection with IAlloc
**/
template <typename GcObjectInterface>
struct FallbackGcInterface {
template <typename Allocator>
FallbackGcInterface(Allocator & alloc) {}
bool check_write_barrier(const void * parent,
const void * const * lhs,
bool may_throw) { return true; };
};
/** Extended version of
* std::allocator_traits<Allocator>
* Introduces additional i/face methods
@ -136,6 +149,8 @@ namespace xo {
using super::allocate;
using super::deallocate;
// ----------------------------------------------------------------
// default: allocator A fallback to standard non-gc allocator behavior
template <typename A, typename = void>
struct has_incremental_gc_interface : std::false_type {};
@ -148,6 +163,19 @@ namespace xo {
struct has_incremental_gc_interface<A, std::void_t<typename A::has_incremental_gc_interface>> :
A::has_incremental_gc_interface {};
/** true iff this allocator advertises itself as an incremental collector.
* Allocator will include:
*
* struct IAlloc {
* using has_incremental_gc_interface = std::true_type;
* };
**/
static inline constexpr
bool
has_incremental_gc_interface_v = has_incremental_gc_interface<Allocator>::value;
// ----------------------------------------------------------------
// default: allocate A fallback to standard non-GC allocator behavior
template <typename A, typename = void>
struct has_trivial_deallocate : std::false_type {};
@ -160,6 +188,19 @@ namespace xo {
struct has_trivial_deallocate<A, std::void_t<typename A::has_trivial_deallocate>> :
A::has_trivial_deallocate {};
/** true iff this allocator advertises trivial deallocate
* Allocate will include:
*
* struct IAlloc {
* using has_trivial_deallocate = std::true_type;
* };
**/
static inline constexpr
bool
has_trivial_deallocate_v = has_trivial_deallocate<Allocator>::value;
// ----------------------------------------------------------------
// default: empty object interface.
//
// classes that want to conditionally support GC
@ -187,27 +228,32 @@ namespace xo {
//
using object_interface_type = object_interface<Allocator>;
/** true iff this allocator advertises itself as an incremental collector.
* Allocator will include:
*
* struct IAlloc {
* using has_incremental_gc_interface = std::true_type;
* };
**/
static inline constexpr
bool
has_incremental_gc_interface_v = has_incremental_gc_interface<Allocator>::value;
// ----------------------------------------------------------------
// default: minimal garbage collector interface.
//
// Use in allocator-aware components that need conditionally
// to engage with GC functionality.
// For example in RedBlackTree::verify_ok() want to check
// cross-generational pointers.
//
// gc_interface gc
// - gc_interface(A & alloc)
// - gc.check_write_barrier(const object_interface_type * p,
// const object_interface_type * const * lhs,
// bool may_throw)
//
template <typename A, typename = void>
struct gc_interface : public FallbackGcInterface<object_interface_type> {};
// allocator opt-in by providing a gc_interface type
template <typename A>
struct gc_interface<A, std::void_t<typename A::gc_interface>> : public A::gc_interface {};
// interface for (narrow) GC interaction.
// Construct from allocator
using gc_interface_type = gc_interface<Allocator>;
/** true iff this allocator advertises trivial deallocate
* Allocate will include:
*
* struct IAlloc {
* using has_trivial_deallocate = std::true_type;
* };
**/
static inline constexpr
bool
has_trivial_deallocate_v = has_trivial_deallocate<Allocator>::value;
};
} /*namespace gc*/
} /*namespace xo*/