Ryujinx/Ryujinx.Graphics.Shader/Translation/ControlFlowGraph.cs
2020-01-09 02:13:00 +01:00

108 lines
3.1 KiB
C#

using Ryujinx.Graphics.Shader.IntermediateRepresentation;
using System.Collections.Generic;
namespace Ryujinx.Graphics.Shader.Translation
{
static class ControlFlowGraph
{
public static BasicBlock[] MakeCfg(Operation[] operations)
{
Dictionary<Operand, BasicBlock> labels = new Dictionary<Operand, BasicBlock>();
List<BasicBlock> blocks = new List<BasicBlock>();
BasicBlock currentBlock = null;
void NextBlock(BasicBlock nextBlock)
{
if (currentBlock != null && !EndsWithUnconditionalInst(currentBlock.GetLastOp()))
{
currentBlock.Next = nextBlock;
}
currentBlock = nextBlock;
}
void NewNextBlock()
{
BasicBlock block = new BasicBlock(blocks.Count);
blocks.Add(block);
NextBlock(block);
}
bool needsNewBlock = true;
for (int index = 0; index < operations.Length; index++)
{
Operation operation = operations[index];
if (operation.Inst == Instruction.MarkLabel)
{
Operand label = operation.Dest;
if (labels.TryGetValue(label, out BasicBlock nextBlock))
{
nextBlock.Index = blocks.Count;
blocks.Add(nextBlock);
NextBlock(nextBlock);
}
else
{
NewNextBlock();
labels.Add(label, currentBlock);
}
}
else
{
if (needsNewBlock)
{
NewNextBlock();
}
currentBlock.Operations.AddLast(operation);
}
needsNewBlock = operation.Inst == Instruction.Branch ||
operation.Inst == Instruction.BranchIfTrue ||
operation.Inst == Instruction.BranchIfFalse;
if (needsNewBlock)
{
Operand label = operation.Dest;
if (!labels.TryGetValue(label, out BasicBlock branchBlock))
{
branchBlock = new BasicBlock();
labels.Add(label, branchBlock);
}
currentBlock.Branch = branchBlock;
}
}
return blocks.ToArray();
}
private static bool EndsWithUnconditionalInst(INode node)
{
if (node is Operation operation)
{
switch (operation.Inst)
{
case Instruction.Branch:
case Instruction.Discard:
case Instruction.Return:
return true;
}
}
return false;
}
}
}