Previously, a wide slab could be freed during this phase which could
trigger the superpage itself to be freed, resulting in iteration across
potentially invalid memory if the superpage was returned to the host and
not placed in the orphanage.
`heap_free_wide_slab` has had its responsibilities reduced to just
freeing the wide slab, and `heap_free_superpage_if_empty_and_unused` has
been added to better clarify what is happening where.
This should be more robust during merges that happen simultaneously with
remote frees.
Previously, we would preserve the cache entry, but there is an edge case
where a slab of a lower index could be remotely freed and missed during
a merge.
- Simplify the malloc-based allocator
- Correct the type signatures on malloc/calloc/realloc
- Make `heap_alloc/heap_free/heap_resize` API consistent across platforms
- Add the test bench for the allocator
- Move old allocator code to the test bench
- Fix `heap_resize` usage in `os2/env_linux.odin` to fit new API
requiring `old_size`
The new reduce_add/reduce_mul procs perform the corresponding arithmetic
reduction in different orders than sequential order. These alternative
orders can often offer better SIMD hardware utilization.
Two different orders are added: pair-wise (operating on pairs of
adjacent elements) or bisection-wise (operating element-wise on the
first and last N/2 elements of the vector).
allocators
This adds various bindings to the asan runtime which can be used
to poison/unpoison memory handed out by various allocators. This
means we can catch use after free memory bugs when using operations
such as free_all during runtime.
Asan poisoning are added for the follow allocators in mem:
Arena (including temporary arenas)
Scratch
Stack
Small_Stack
Additionally a bug in the stack allocator was fixed to disallow freeing
in the middle of the stack (caught by the asan!).
I plan on adding support for all the allocators in core. This is just
a good starting point and were some of the easiest ones to implement
asan for.
