drashna/ryujinx
1
0
Fork 0
Code Activity Actions

Reduce JIT GC allocations (#2515)

Browse source 
* 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

* Add `Allocators` class

* Tune `ArenaAllocator` sizes

* Add page removal mechanism to `ArenaAllocator`

Remove pages which have not been used for more than 5s after each reset.

I am on fence if this would be better using a Gen2 callback object like
the one in System.Buffers.ArrayPool<T>, to trim the pool. Because right
now if a large translation happens, the pages will be freed only after a
reset. This reset may not happen for a while because no new translation
is hit, but the arena base sizes are rather small.

* Fix `OOM` when allocating larger than page size in `ArenaAllocator`

Tweak resizing mechanism for Operand.Uses and Assignemnts.

* Optimize `Optimizer` a bit

* Optimize `Operand.Add<T>/Remove<T>` a bit

* Clean up `PreAllocator`

* Fix phi insertion order

Reduce codegen diffs.

* Fix code alignment

* Use new heuristics for degree of parallelism

* Suppress warnings

* Address gdkchan's feedback

Renamed `GetValue()` to `GetValueUnsafe()` to make it more clear that
`Operand.Value` should usually not be modified directly.

* Add fast path to `ArenaAllocator`

* Assembly for `ArenaAllocator.Allocate(ulong)`:

  .L0:
    mov rax, [rcx+0x18]
    lea r8, [rax+rdx]
    cmp r8, [rcx+0x10]
    ja short .L2
  .L1:
    mov rdx, [rcx+8]
    add rax, [rdx+8]
    mov [rcx+0x18], r8
    ret
  .L2:
    jmp ArenaAllocator.AllocateSlow(UInt64)

  A few variable/field had to be changed to ulong so that RyuJIT avoids
  emitting zero-extends.

* Implement a new heuristic to free pooled pages.

  If an arena is used often, it is more likely that its pages will be
  needed, so the pages are kept for longer (e.g: during PPTC rebuild or
  burst sof compilations). If is not used often, then it is more likely
  that its pages will not be needed (e.g: after PPTC rebuild or bursts
  of compilations).

* Address riperiperi's feedback

* Use `EqualityComparer<T>` in `IntrusiveList<T>`

Avoids a potential GC hole in `Equals(T, T)`.
This commit is contained in:
FICTURE7 2021-08-17 22:08:34 +04:00 • committed by GitHub
parent cd4530f29c
commit 22b2cb39af
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
91 changed files with 2354 additions and 2142 deletions
Download patch file Download diff file Expand all files Collapse all files

157
ARMeilleure/Common/BitMap.cs
View file

@ -1,57 +1,27 @@
using System;
using System.Collections;
using System.Collections.Generic;
using System.Numerics;
namespace ARMeilleure.Common
{
class BitMap : IEnumerator<int>, IEnumerable<int>
unsafe class BitMap : IEnumerable<int>, IDisposable
{
private const int IntSize = 64;
private const int IntMask = IntSize - 1;
private readonly List<long> _masks;
private int _count;
private long* _masks;
private readonly Allocator _allocator;
private int _enumIndex;
private long _enumMask;
private int _enumBit;
public int Current => _enumIndex * IntSize + _enumBit;
object IEnumerator.Current => Current;
public BitMap()
public BitMap(Allocator allocator)
{
_masks = new List<long>(0);
_allocator = allocator;
}
public BitMap(int initialCapacity)
public BitMap(Allocator allocator, int capacity) : this(allocator)
{
int count = (initialCapacity + IntMask) / IntSize;
_masks = new List<long>(count);
while (count-- > 0)
{
_masks.Add(0);
}
}
public BitMap Reset(int initialCapacity)
{
int count = (initialCapacity + IntMask) / IntSize;
if (count > _masks.Capacity)
{
_masks.Capacity = count;
}
_masks.Clear();
while (count-- > 0)
{
_masks.Add(0);
}
return this;
EnsureCapacity(capacity);
}
public bool Set(int bit)
@ -97,7 +67,7 @@ namespace ARMeilleure.Common
public int FindFirstUnset()
{
for (int index = 0; index < _masks.Count; index++)
for (int index = 0; index < _count; index++)
{
long mask = _masks[index];
@ -107,16 +77,16 @@ namespace ARMeilleure.Common
}
}
return _masks.Count * IntSize;
return _count * IntSize;
}
public bool Set(BitMap map)
{
EnsureCapacity(map._masks.Count * IntSize);
EnsureCapacity(map._count * IntSize);
bool modified = false;
for (int index = 0; index < _masks.Count; index++)
for (int index = 0; index < _count; index++)
{
long newValue = _masks[index] | map._masks[index];
@ -133,11 +103,11 @@ namespace ARMeilleure.Common
public bool Clear(BitMap map)
{
EnsureCapacity(map._masks.Count * IntSize);
EnsureCapacity(map._count * IntSize);
bool modified = false;
for (int index = 0; index < _masks.Count; index++)
for (int index = 0; index < _count; index++)
{
long newValue = _masks[index] & ~map._masks[index];
@ -152,15 +122,34 @@ namespace ARMeilleure.Common
return modified;
}
#region IEnumerable<long> Methods
// Note: The bit enumerator is embedded in this class to avoid creating garbage when enumerating.
private void EnsureCapacity(int size)
{
while (_masks.Count * IntSize < size)
int count = (size + IntMask) / IntSize;
if (count > _count)
{
_masks.Add(0);
var oldMask = _masks;
var oldSpan = new Span<long>(_masks, _count);
_masks = _allocator.Allocate<long>((uint)count);
_count = count;
var newSpan = new Span<long>(_masks, _count);
oldSpan.CopyTo(newSpan);
newSpan.Slice(oldSpan.Length).Clear();
_allocator.Free(oldMask);
}
}
public void Dispose()
{
if (_masks != null)
{
_allocator.Free(_masks);
_masks = null;
}
}
@ -169,39 +158,59 @@ namespace ARMeilleure.Common
return GetEnumerator();
}
public IEnumerator<int> GetEnumerator()
IEnumerator<int> IEnumerable<int>.GetEnumerator()
{
Reset();
return this;
return GetEnumerator();
}
public bool MoveNext()
public Enumerator GetEnumerator()
{
if (_enumMask != 0)
return new Enumerator(this);
}
public struct Enumerator : IEnumerator<int>
{
private int _index;
private long _mask;
private int _bit;
private readonly BitMap _map;
public int Current => _index * IntSize + _bit;
object IEnumerator.Current => Current;
public Enumerator(BitMap map)
{
_enumMask &= ~(1L << _enumBit);
_index = -1;
_mask = 0;
_bit = 0;
_map = map;
}
while (_enumMask == 0)
public bool MoveNext()
{
if (++_enumIndex >= _masks.Count)
if (_mask != 0)
{
return false;
_mask &= ~(1L << _bit);
}
_enumMask = _masks[_enumIndex];
while (_mask == 0)
{
if (++_index >= _map._count)
{
return false;
}
_mask = _map._masks[_index];
}
_bit = BitOperations.TrailingZeroCount(_mask);
return true;
}
_enumBit = BitOperations.TrailingZeroCount(_enumMask);
return true;
public void Reset() { }
public void Dispose() { }
}
public void Reset()
{
_enumIndex = -1;
_enumMask = 0;
_enumBit = 0;
}
public void Dispose() { }
#endregion
}
}