ryujinx/Ryujinx.Graphics.Shader/CodeGen/Glsl/GlslGenerator.cs
2020-01-09 02:13:00 +01:00

152 lines
5.5 KiB
C#

using Ryujinx.Graphics.Shader.CodeGen.Glsl.Instructions;
using Ryujinx.Graphics.Shader.IntermediateRepresentation;
using Ryujinx.Graphics.Shader.StructuredIr;
using Ryujinx.Graphics.Shader.Translation;
using System;
using static Ryujinx.Graphics.Shader.CodeGen.Glsl.TypeConversion;
namespace Ryujinx.Graphics.Shader.CodeGen.Glsl
{
static class GlslGenerator
{
public static GlslProgram Generate(StructuredProgramInfo info, ShaderConfig config)
{
CodeGenContext context = new CodeGenContext(config);
Declarations.Declare(context, info);
PrintMainBlock(context, info);
return new GlslProgram(
context.CBufferDescriptors.ToArray(),
context.SBufferDescriptors.ToArray(),
context.TextureDescriptors.ToArray(),
context.ImageDescriptors.ToArray(),
context.GetCode());
}
private static void PrintMainBlock(CodeGenContext context, StructuredProgramInfo info)
{
context.AppendLine("void main()");
context.EnterScope();
Declarations.DeclareLocals(context, info);
// Some games will leave some elements of gl_Position uninitialized,
// in those cases, the elements will contain undefined values according
// to the spec, but on NVIDIA they seems to be always initialized to (0, 0, 0, 1),
// so we do explicit initialization to avoid UB on non-NVIDIA gpus.
if (context.Config.Stage == ShaderStage.Vertex)
{
context.AppendLine("gl_Position = vec4(0.0, 0.0, 0.0, 1.0);");
}
// Ensure that unused attributes are set, otherwise the downstream
// compiler may eliminate them.
// (Not needed for fragment shader as it is the last stage).
if (context.Config.Stage != ShaderStage.Compute &&
context.Config.Stage != ShaderStage.Fragment)
{
for (int attr = 0; attr < Declarations.MaxAttributes; attr++)
{
if (info.OAttributes.Contains(attr))
{
continue;
}
context.AppendLine($"{DefaultNames.OAttributePrefix}{attr} = vec4(0);");
}
}
PrintBlock(context, info.MainBlock);
context.LeaveScope();
}
private static void PrintBlock(CodeGenContext context, AstBlock block)
{
AstBlockVisitor visitor = new AstBlockVisitor(block);
visitor.BlockEntered += (sender, e) =>
{
switch (e.Block.Type)
{
case AstBlockType.DoWhile:
context.AppendLine("do");
break;
case AstBlockType.Else:
context.AppendLine("else");
break;
case AstBlockType.ElseIf:
context.AppendLine($"else if ({GetCondExpr(context, e.Block.Condition)})");
break;
case AstBlockType.If:
context.AppendLine($"if ({GetCondExpr(context, e.Block.Condition)})");
break;
default: throw new InvalidOperationException($"Found unexpected block type \"{e.Block.Type}\".");
}
context.EnterScope();
};
visitor.BlockLeft += (sender, e) =>
{
context.LeaveScope();
if (e.Block.Type == AstBlockType.DoWhile)
{
context.AppendLine($"while ({GetCondExpr(context, e.Block.Condition)});");
}
};
foreach (IAstNode node in visitor.Visit())
{
if (node is AstOperation operation)
{
context.AppendLine(InstGen.GetExpression(context, operation) + ";");
}
else if (node is AstAssignment assignment)
{
VariableType srcType = OperandManager.GetNodeDestType(assignment.Source);
VariableType dstType = OperandManager.GetNodeDestType(assignment.Destination);
string dest;
if (assignment.Destination is AstOperand operand && operand.Type == OperandType.Attribute)
{
dest = OperandManager.GetOutAttributeName(operand, context.Config.Stage);
}
else
{
dest = InstGen.GetExpression(context, assignment.Destination);
}
string src = ReinterpretCast(context, assignment.Source, srcType, dstType);
context.AppendLine(dest + " = " + src + ";");
}
else if (node is AstComment comment)
{
context.AppendLine("// " + comment.Comment);
}
else
{
throw new InvalidOperationException($"Found unexpected node type \"{node?.GetType().Name ?? "null"}\".");
}
}
}
private static string GetCondExpr(CodeGenContext context, IAstNode cond)
{
VariableType srcType = OperandManager.GetNodeDestType(cond);
return ReinterpretCast(context, cond, srcType, VariableType.Bool);
}
}
}