SwizzleAdd (NOT TESTED)

src/Ryujinx.Graphics.Shader/CodeGen/Msl/Declarations.cs

@@ -65,11 +65,6 @@ namespace Ryujinx.Graphics.Shader.CodeGen.Msl
             context.AppendLine("using namespace metal;");
             context.AppendLine();
 
-            if ((info.HelperFunctionsMask & HelperFunctionsMask.SwizzleAdd) != 0)
-            {
-
-            }
-
             DeclareInputAttributes(context, info.IoDefinitions.Where(x => IsUserDefined(x, StorageKind.Input)));
             context.AppendLine();
             DeclareOutputAttributes(context, info.IoDefinitions.Where(x => x.StorageKind == StorageKind.Output));
@@ -93,6 +88,11 @@ namespace Ryujinx.Graphics.Shader.CodeGen.Msl
             {
                 AppendHelperFunction(context, "Ryujinx.Graphics.Shader/CodeGen/Msl/HelperFunctions/FindMSBU32.metal");
             }
+
+            if ((info.HelperFunctionsMask & HelperFunctionsMask.SwizzleAdd) != 0)
+            {
+                AppendHelperFunction(context, "Ryujinx.Graphics.Shader/CodeGen/Msl/HelperFunctions/SwizzleAdd.metal");
+            }
         }
 
         static bool IsUserDefined(IoDefinition ioDefinition, StorageKind storageKind)

src/Ryujinx.Graphics.Shader/CodeGen/Msl/HelperFunctions/HelperFunctionNames.cs

@@ -5,5 +5,6 @@ namespace Ryujinx.Graphics.Shader.CodeGen.Msl
         public static string FindLSB = "findLSB";
         public static string FindMSBS32 = "findMSBS32";
         public static string FindMSBU32 = "findMSBU32";
+        public static string SwizzleAdd = "swizzleAdd";
     }
 }

src/Ryujinx.Graphics.Shader/CodeGen/Msl/HelperFunctions/SwizzleAdd.metal

@@ -0,0 +1,7 @@
+float swizzleAdd(float x, float y, int mask, uint thread_index_in_simdgroup)
+{
+    float4 xLut = float4(1.0, -1.0, 1.0, 0.0);
+    float4 yLut = float4(1.0, 1.0, -1.0, 1.0);
+    int lutIdx = (mask >> (int(thread_index_in_simdgroup & 3u) * 2)) & 3;
+    return x * xLut[lutIdx] + y * yLut[lutIdx];
+}

src/Ryujinx.Graphics.Shader/CodeGen/Msl/Instructions/InstGen.cs

@@ -69,6 +69,12 @@ namespace Ryujinx.Graphics.Shader.CodeGen.Msl.Instructions
 
                         builder.Append(GetSourceExpr(context, operation.GetSource(argIndex), dstType));
                     }
+
+                    if ((operation.Inst & Instruction.Mask) == Instruction.SwizzleAdd)
+                    {
+                        // SwizzleAdd takes one last argument, the thread_index_in_simdgroup
+                        builder.Append(", thread_index_in_simdgroup");
+                    }
                 }
 
                 return $"{info.OpName}({builder})";
@@ -142,8 +148,6 @@ namespace Ryujinx.Graphics.Shader.CodeGen.Msl.Instructions
                         return Lod(context, operation);
                     case Instruction.Store:
                         return Store(context, operation);
-                    case Instruction.SwizzleAdd:
-                        return "|| SWIZZLE ADD ||";
                     case Instruction.TextureSample:
                         return TextureSample(context, operation);
                     case Instruction.TextureQuerySamples:

src/Ryujinx.Graphics.Shader/CodeGen/Msl/Instructions/InstGenHelper.cs

@@ -116,7 +116,7 @@ namespace Ryujinx.Graphics.Shader.CodeGen.Msl.Instructions
             Add(Instruction.SquareRoot,               InstType.CallUnary,      "sqrt");
             Add(Instruction.Store,                    InstType.Special);
             Add(Instruction.Subtract,                 InstType.OpBinary,       "-",  2);
-            Add(Instruction.SwizzleAdd,               InstType.Special);
+            Add(Instruction.SwizzleAdd,               InstType.CallTernary,    HelperFunctionNames.SwizzleAdd);
             Add(Instruction.TextureSample,            InstType.Special);
             Add(Instruction.TextureQuerySamples,      InstType.Special);
             Add(Instruction.TextureQuerySize,         InstType.Special);

src/Ryujinx.Graphics.Shader/Ryujinx.Graphics.Shader.csproj

@@ -19,5 +19,6 @@
     <EmbeddedResource Include="CodeGen\Msl\HelperFunctions\FindLSB.metal" />
     <EmbeddedResource Include="CodeGen\Msl\HelperFunctions\FindMSBS32.metal" />
     <EmbeddedResource Include="CodeGen\Msl\HelperFunctions\FindMSBU32.metal" />
+    <EmbeddedResource Include="CodeGen\Msl\HelperFunctions\SwizzleAdd.metal" />
   </ItemGroup>
 </Project>