1 files changed, 48 insertions, 7 deletions
diff --git a/Ryujinx.HLE/HOS/Tamper/CodeEmitters/EndConditionalBlock.cs b/Ryujinx.HLE/HOS/Tamper/CodeEmitters/EndConditionalBlock.cs
index 4a01992c..a25dddde 100644
--- a/Ryujinx.HLE/HOS/Tamper/CodeEmitters/EndConditionalBlock.cs
+++ b/Ryujinx.HLE/HOS/Tamper/CodeEmitters/EndConditionalBlock.cs
@@ -10,32 +10,73 @@ namespace Ryujinx.HLE.HOS.Tamper.CodeEmitters
     /// </summary>
     class EndConditionalBlock
     {
+        const int TerminationTypeIndex = 1;
+
+        private const byte End  = 0; // True end of the conditional.
+        private const byte Else = 1; // End of the 'then' block and beginning of 'else' block.
+
         public static void Emit(byte[] instruction, CompilationContext context)
         {
-            // 20000000
+            Emit(instruction, context, null);
+        }
+
+        private static void Emit(byte[] instruction, CompilationContext context, IEnumerable<IOperation> operationsElse)
+        {
+            // 2X000000
+            // X: End type (0 = End, 1 = Else).
+
+            byte terminationType = instruction[TerminationTypeIndex];
+
+            switch (terminationType)
+            {
+                case End:
+                    break;
+                case Else:
+                    // Start a new operation block with the 'else' instruction to signal that there is the 'then' block just above it.
+                    context.BlockStack.Push(new OperationBlock(instruction));
+                    return;
+                default:
+                    throw new TamperCompilationException($"Unknown conditional termination type {terminationType}");
+            }
 
             // Use the conditional begin instruction stored in the stack.
-            instruction = context.CurrentBlock.BaseInstruction;
-            CodeType codeType = InstructionHelper.GetCodeType(instruction);
+            var upperInstruction = context.CurrentBlock.BaseInstruction;
+            CodeType codeType = InstructionHelper.GetCodeType(upperInstruction);
 
             // Pop the current block of operations from the stack so control instructions
             // for the conditional can be emitted in the upper block.
             IEnumerable<IOperation> operations = context.CurrentOperations;
             context.BlockStack.Pop();
 
+            // If the else operations are already set, then the upper block must not be another end.
+            if (operationsElse != null && codeType == CodeType.EndConditionalBlock)
+            {
+                throw new TamperCompilationException($"Expected an upper 'if' conditional instead of 'end conditional'");
+            }
+
             ICondition condition;
 
             switch (codeType)
             {
                 case CodeType.BeginMemoryConditionalBlock:
-                    condition = MemoryConditional.Emit(instruction, context);
+                    condition = MemoryConditional.Emit(upperInstruction, context);
                     break;
                 case CodeType.BeginKeypressConditionalBlock:
-                    condition = KeyPressConditional.Emit(instruction, context);
+                    condition = KeyPressConditional.Emit(upperInstruction, context);
                     break;
                 case CodeType.BeginRegisterConditionalBlock:
-                    condition = RegisterConditional.Emit(instruction, context);
+                    condition = RegisterConditional.Emit(upperInstruction, context);
                     break;
+                case CodeType.EndConditionalBlock:
+                    terminationType = upperInstruction[TerminationTypeIndex];
+                    // If there is an end instruction above then it must be an else.
+                    if (terminationType != Else)
+                    {
+                        throw new TamperCompilationException($"Expected an upper 'else' conditional instead of {terminationType}");
+                    }
+                    // Re-run the Emit with the else operations set.
+                    Emit(instruction, context, operations);
+                    return;
                 default:
                     throw new TamperCompilationException($"Conditional end does not match code type {codeType} in Atmosphere cheat");
             }
@@ -43,7 +84,7 @@ namespace Ryujinx.HLE.HOS.Tamper.CodeEmitters
             // Create a conditional block with the current operations and nest it in the upper
             // block of the stack.
 
-            IfBlock block = new IfBlock(condition, operations);
+            IfBlock block = new IfBlock(condition, operations, operationsElse);
             context.CurrentOperations.Add(block);
         }
     }