SPIR-V: Geometry shader passthrough support

Ryujinx.Graphics.Shader/CodeGen/Spirv/Declarations.cs

@@ -385,6 +385,11 @@ namespace Ryujinx.Graphics.Shader.CodeGen.Spirv
                         var spvType = context.TypePointer(StorageClass.Input, attrType);
                         var spvVar = context.Variable(spvType, StorageClass.Input);
 
+                        if (context.Config.PassthroughAttributes != 0)
+                        {
+                            context.Decorate(spvVar, Decoration.PassthroughNV);
+                        }
+
                         context.Decorate(spvVar, Decoration.Location, (LiteralInteger)0);
 
                         context.AddGlobalVariable(spvVar);
@@ -483,10 +488,16 @@ namespace Ryujinx.Graphics.Shader.CodeGen.Spirv
 
             var storageClass = isOutAttr ? StorageClass.Output : StorageClass.Input;
             var attrType = context.GetType(attrInfo.Type, attrInfo.Length);
+            bool builtInPassthrough = false;
 
             if (context.Config.Stage == ShaderStage.Geometry && !isOutAttr && (!attrInfo.IsBuiltin || AttributeInfo.IsArrayBuiltIn(attr)))
             {
                 attrType = context.TypeArray(attrType, context.Constant(context.TypeU32(), (LiteralInteger)context.InputVertices));
+
+                if (context.Config.GpPassthrough)
+                {
+                    builtInPassthrough = true;
+                }
             }
 
             var spvType = context.TypePointer(storageClass, attrType);
@@ -497,6 +508,11 @@ namespace Ryujinx.Graphics.Shader.CodeGen.Spirv
                 context.Decorate(spvVar, Decoration.Patch);
             }
 
+            if (builtInPassthrough)
+            {
+                context.Decorate(spvVar, Decoration.PassthroughNV);
+            }
+
             if (attrInfo.IsBuiltin)
             {
                 context.Decorate(spvVar, Decoration.BuiltIn, (LiteralInteger)GetBuiltIn(context, attrInfo.BaseValue));
@@ -525,6 +541,11 @@ namespace Ryujinx.Graphics.Shader.CodeGen.Spirv
 
                 if (!isOutAttr)
                 {
+                    if (!perPatch && (context.Config.PassthroughAttributes & (1 << location)) != 0)
+                    {
+                        context.Decorate(spvVar, Decoration.PassthroughNV);
+                    }
+
                     switch (iq)
                     {
                         case PixelImap.Constant:
@@ -585,6 +606,11 @@ namespace Ryujinx.Graphics.Shader.CodeGen.Spirv
             }
             else
             {
+                if ((context.Config.PassthroughAttributes & (1 << location)) != 0)
+                {
+                    context.Decorate(spvVar, Decoration.PassthroughNV);
+                }
+
                 switch (iq)
                 {
                     case PixelImap.Constant:

Ryujinx.Graphics.Shader/CodeGen/Spirv/SpirvGenerator.cs

@@ -69,6 +69,12 @@ namespace Ryujinx.Graphics.Shader.CodeGen.Spirv
             else if (config.Stage == ShaderStage.Geometry)
             {
                 context.AddCapability(Capability.Geometry);
+
+                if (config.GpPassthrough)
+                {
+                    context.AddExtension("SPV_NV_geometry_shader_passthrough");
+                    context.AddCapability(Capability.GeometryShaderPassthroughNV);
+                }
             }
             else if (config.Stage == ShaderStage.TessellationControl || config.Stage == ShaderStage.TessellationEvaluation)
             {

Ryujinx.Graphics.Shader/StructuredIr/StructuredProgramContext.cs

@@ -2,6 +2,7 @@ using Ryujinx.Graphics.Shader.IntermediateRepresentation;
 using Ryujinx.Graphics.Shader.Translation;
 using System.Collections.Generic;
 using System.Linq;
+using System.Numerics;
 
 using static Ryujinx.Graphics.Shader.StructuredIr.AstHelper;
 
@@ -35,6 +36,34 @@ namespace Ryujinx.Graphics.Shader.StructuredIr
             Info = new StructuredProgramInfo();
 
             Config = config;
+
+            if (config.GpPassthrough)
+            {
+                int passthroughAttributes = config.PassthroughAttributes;
+                while (passthroughAttributes != 0)
+                {
+                    int index = BitOperations.TrailingZeroCount(passthroughAttributes);
+
+                    int attrBase = AttributeConsts.UserAttributeBase + index * 16;
+                    Info.Inputs.Add(attrBase);
+                    Info.Inputs.Add(attrBase + 4);
+                    Info.Inputs.Add(attrBase + 8);
+                    Info.Inputs.Add(attrBase + 12);
+
+                    passthroughAttributes &= ~(1 << index);
+                }
+
+                Info.Inputs.Add(AttributeConsts.PositionX);
+                Info.Inputs.Add(AttributeConsts.PositionY);
+                Info.Inputs.Add(AttributeConsts.PositionZ);
+                Info.Inputs.Add(AttributeConsts.PositionW);
+                Info.Inputs.Add(AttributeConsts.PointSize);
+
+                for (int i = 0; i < 8; i++)
+                {
+                    Info.Inputs.Add(AttributeConsts.ClipDistance0 + i * 4);
+                }
+            }
         }
 
         public void EnterFunction(

Ryujinx.Graphics.Vulkan/VulkanInitialization.cs

@@ -32,7 +32,8 @@ namespace Ryujinx.Graphics.Vulkan
             "VK_EXT_fragment_shader_interlock",
             "VK_EXT_index_type_uint8",
             "VK_EXT_robustness2",
-            "VK_EXT_shader_subgroup_ballot"
+            "VK_EXT_shader_subgroup_ballot",
+            "VK_NV_geometry_shader_passthrough"
         };
 
         private static readonly string[] _excludedMessages = new string[]