* Optimize `TryAllocateRegWithtoutSpill` a bit
* Add a fast path for when all registers are live.
* Do not query `GetOverlapPosition` if the register is already in use
(i.e: free position is 0).
* Do not allocate child split list if not parent
* Turn `LiveRange` into a reference struct
`LiveRange` is now a reference wrapping struct like `Operand` and
`Operation`.
It has also been changed into a singly linked-list. In micro-benchmarks
traversing the linked-list was faster than binary search on `List<T>`.
Even for quite large input sizes (e.g: 1,000,000), surprisingly.
Could be because the code gen for traversing the linked-list is much
much cleaner and there is no virtual dispatch happening when checking if
intervals overlaps.
* Turn `LiveInterval` into an iterator
The LSRA allocates in forward order and never inspect previous
`LiveInterval` once they are expired. Something similar can be done for
the `LiveRange`s within the `LiveInterval`s themselves.
The `LiveInterval` is turned into a iterator which expires `LiveRange`
within it. The iterator is moved forward along with interval walking
code, i.e: AllocateInterval(context, interval, cIndex).
* Remove `LinearScanAllocator.Sources`
Local methods are less susceptible to do allocations than lambdas.
* Optimize `GetOverlapPosition(interval)` a bit
Time complexity should be in O(n+m) instead of O(nm) now.
* Optimize `NumberLocals` a bit
Use the same idea as in `HybridAllocator` to store the visited state
in the MSB of the Operand's value instead of using a `HashSet<T>`.
* Optimize `InsertSplitCopies` a bit
Avoid allocating a redundant `CopyResolver`.
* Optimize `InsertSplitCopiesAtEdges` a bit
Avoid redundant allocations of `CopyResolver`.
* Use stack allocation for `freePositions`
Avoid redundant computations.
* Add `UseList`
Replace `SortedIntegerList` with an even more specialized data
structure. It allocates memory on the arena allocators and does not
require copying use positions when splitting it.
* Turn `LiveInterval` into a reference struct
`LiveInterval` is now a reference wrapping struct like `Operand` and
`Operation`.
The rationale behind turning this in a reference wrapping struct is
because a `LiveInterval` is associated with each local variable, and
these intervals may themselves be split further. I've seen translations
having up to 8000 local variables.
To make the `LiveInterval` unmanaged, a new data structure called
`LiveIntervalList` was added to store child splits. This differs from
`SortedList<,>` because it can contain intervals with the same start
position.
Really wished we got some more of C++ template in C#. :^(
* Optimize `GetChildSplit` a bit
No need to inspect the remaining ranges if we've reached a range which
starts after position, since the split list is ordered.
* Optimize `CopyResolver` a bit
Lazily allocate the fill, spill and parallel copy structures since most
of the time only one of them is needed.
* Optimize `BitMap.Enumerator` a bit
Marking `MoveNext` as `AggressiveInlining` allows RyuJIT to promote the
`Enumerator` struct into registers completely, reducing load/store code
a lot since it does not have to store the struct on the stack for ABI
purposes.
* Use stack allocation for `use/blockedPositions`
* Optimize `AllocateWithSpill` a bit
* Address feedback
* Make `LiveInterval.AddRange(,)` more conservative
Produces no diff against master, but just for good measure.
* Turn `MemoryOperand` into a struct
* Remove `IntrinsicOperation`
* Remove `PhiNode`
* Remove `Node`
* Turn `Operand` into a struct
* Turn `Operation` into a struct
* Clean up pool management methods
* Add `Arena` allocator
* Move `OperationHelper` to `Operation.Factory`
* Move `OperandHelper` to `Operand.Factory`
* Optimize `Operation` a bit
* Fix `Arena` initialization
* Rename `NativeList<T>` to `ArenaList<T>`
* Reduce `Operand` size from 88 to 56 bytes
* Reduce `Operation` size from 56 to 40 bytes
* Add optimistic interning of Register & Constant operands
* Optimize `RegisterUsage` pass a bit
* Optimize `RemoveUnusedNodes` pass a bit
Iterating in reverse-order allows killing dependency chains in a single
pass.
* Fix PPTC symbols
* Optimize `BasicBlock` a bit
Reduce allocations from `_successor` & `DominanceFrontiers`
* Fix `Operation` resize
* Make `Arena` expandable
Change the arena allocator to be expandable by allocating in pages, with
some of them being pooled. Currently 32 pages are pooled. An LRU removal
mechanism should probably be added to it.
Apparently MHR can allocate bitmaps large enough to exceed the 16MB
limit for the type.
* Move `Arena` & `ArenaList` to `Common`
* Remove `ThreadStaticPool` & co
* Add `PhiOperation`
* Reduce `Operand` size from 56 from 48 bytes
* Add linear-probing to `Operand` intern table
* Optimize `HybridAllocator` a bit
*
FICTURE7