rjx-mirror/Ryujinx.Graphics/Gal/Shader/ShaderDecoder.cs

204 lines
No EOL
6.3 KiB
C#

using System.Collections.Generic;
namespace Ryujinx.Graphics.Gal.Shader
{
static class ShaderDecoder
{
private const bool AddDbgComments = true;
public static ShaderIrBlock[] Decode(IGalMemory Memory, long Start)
{
Dictionary<long, ShaderIrBlock> Visited = new Dictionary<long, ShaderIrBlock>();
Dictionary<long, ShaderIrBlock> VisitedEnd = new Dictionary<long, ShaderIrBlock>();
Queue<ShaderIrBlock> Blocks = new Queue<ShaderIrBlock>();
ShaderIrBlock Enqueue(long Position, ShaderIrBlock Source = null)
{
if (!Visited.TryGetValue(Position, out ShaderIrBlock Output))
{
Output = new ShaderIrBlock(Position);
Blocks.Enqueue(Output);
Visited.Add(Position, Output);
}
if (Source != null)
{
Output.Sources.Add(Source);
}
return Output;
}
ShaderIrBlock Entry = Enqueue(Start);
while (Blocks.Count > 0)
{
ShaderIrBlock Current = Blocks.Dequeue();
FillBlock(Memory, Current);
//Set child blocks. "Branch" is the block the branch instruction
//points to (when taken), "Next" is the block at the next address,
//executed when the branch is not taken. For Unconditional Branches
//or end of shader, Next is null.
if (Current.Nodes.Count > 0)
{
ShaderIrNode LastNode = Current.GetLastNode();
ShaderIrOp Op = GetInnermostOp(LastNode);
if (Op?.Inst == ShaderIrInst.Bra)
{
int Offset = ((ShaderIrOperImm)Op.OperandA).Value;
long Target = Current.EndPosition + Offset;
Current.Branch = Enqueue(Target, Current);
}
if (NodeHasNext(LastNode))
{
Current.Next = Enqueue(Current.EndPosition);
}
}
//If we have on the graph two blocks with the same end position,
//then we need to split the bigger block and have two small blocks,
//the end position of the bigger "Current" block should then be == to
//the position of the "Smaller" block.
while (VisitedEnd.TryGetValue(Current.EndPosition, out ShaderIrBlock Smaller))
{
if (Current.Position > Smaller.Position)
{
ShaderIrBlock Temp = Smaller;
Smaller = Current;
Current = Temp;
}
Current.EndPosition = Smaller.Position;
Current.Next = Smaller;
Current.Branch = null;
Current.Nodes.RemoveRange(
Current.Nodes.Count - Smaller.Nodes.Count,
Smaller.Nodes.Count);
VisitedEnd[Smaller.EndPosition] = Smaller;
}
VisitedEnd.Add(Current.EndPosition, Current);
}
//Make and sort Graph blocks array by position.
ShaderIrBlock[] Graph = new ShaderIrBlock[Visited.Count];
while (Visited.Count > 0)
{
ulong FirstPos = ulong.MaxValue;
foreach (ShaderIrBlock Block in Visited.Values)
{
if (FirstPos > (ulong)Block.Position)
FirstPos = (ulong)Block.Position;
}
ShaderIrBlock Current = Visited[(long)FirstPos];
do
{
Graph[Graph.Length - Visited.Count] = Current;
Visited.Remove(Current.Position);
Current = Current.Next;
}
while (Current != null);
}
return Graph;
}
private static void FillBlock(IGalMemory Memory, ShaderIrBlock Block)
{
long Position = Block.Position;
do
{
//Ignore scheduling instructions, which are written every 32 bytes.
if ((Position & 0x1f) == 0)
{
Position += 8;
continue;
}
uint Word0 = (uint)Memory.ReadInt32(Position + 0);
uint Word1 = (uint)Memory.ReadInt32(Position + 4);
Position += 8;
long OpCode = Word0 | (long)Word1 << 32;
ShaderDecodeFunc Decode = ShaderOpCodeTable.GetDecoder(OpCode);
if (AddDbgComments)
{
string DbgOpCode = $"0x{(Position - 8):x16}: 0x{OpCode:x16} ";
DbgOpCode += (Decode?.Method.Name ?? "???");
if (Decode == ShaderDecode.Bra)
{
int Offset = ((int)(OpCode >> 20) << 8) >> 8;
long Target = Position + Offset;
DbgOpCode += " (0x" + Target.ToString("x16") + ")";
}
Block.AddNode(new ShaderIrCmnt(DbgOpCode));
}
if (Decode == null)
{
continue;
}
Decode(Block, OpCode);
}
while (!IsFlowChange(Block.GetLastNode()));
Block.EndPosition = Position;
}
private static bool IsFlowChange(ShaderIrNode Node)
{
return !NodeHasNext(GetInnermostOp(Node));
}
private static ShaderIrOp GetInnermostOp(ShaderIrNode Node)
{
if (Node is ShaderIrCond Cond)
{
Node = Cond.Child;
}
return Node is ShaderIrOp Op ? Op : null;
}
private static bool NodeHasNext(ShaderIrNode Node)
{
if (!(Node is ShaderIrOp Op))
{
return true;
}
return Op.Inst != ShaderIrInst.Exit &&
Op.Inst != ShaderIrInst.Bra;
}
}
}