From 367034373f2451778c0ec4df50467c28a7eb08bd Mon Sep 17 00:00:00 2001
From: Merlin <36685500+Merlin-san@users.noreply.github.com>
Date: Tue, 7 Apr 2020 16:26:07 -0700
Subject: [PATCH] More leniant handling on the binary expression copying

- Only create a new intermediate value when we captured a scope that hasn't already necessarily created a new intermediate variable
---
 .../UdonSharp/Editor/UdonSharpASTVisitor.cs   | 19 +++++++++++++------
 .../Editor/UdonSharpExpressionCapture.cs      |  5 +++++
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/Assets/UdonSharp/Editor/UdonSharpASTVisitor.cs b/Assets/UdonSharp/Editor/UdonSharpASTVisitor.cs
index 1bb7b7db..f432bbc5 100644
--- a/Assets/UdonSharp/Editor/UdonSharpASTVisitor.cs
+++ b/Assets/UdonSharp/Editor/UdonSharpASTVisitor.cs
@@ -1574,15 +1574,22 @@ public override void VisitBinaryExpression(BinaryExpressionSyntax node)
             {
                 Visit(node.Left);
 
-                // This needs to be copied because someone can do an in place assignment operator on the rhs that changes the lhs value
-                SymbolDefinition lhsCopy = visitorContext.topTable.CreateUnnamedSymbol(lhsCapture.GetReturnType(true), SymbolDeclTypeFlags.Internal);
-                using (ExpressionCaptureScope lhsCopySetter = new ExpressionCaptureScope(visitorContext, null))
+                if (lhsCapture.DoesReturnIntermediateSymbol())
                 {
-                    lhsCopySetter.SetToLocalSymbol(lhsCopy);
-                    lhsCopySetter.ExecuteSetDirect(lhsCapture);
+                    lhsValue = lhsCapture.ExecuteGet();
                 }
+                else
+                {
+                    // This needs to be copied because someone can do an in place assignment operator on the rhs that changes the lhs value
+                    SymbolDefinition lhsCopy = visitorContext.topTable.CreateUnnamedSymbol(lhsCapture.GetReturnType(true), SymbolDeclTypeFlags.Internal);
+                    using (ExpressionCaptureScope lhsCopySetter = new ExpressionCaptureScope(visitorContext, null))
+                    {
+                        lhsCopySetter.SetToLocalSymbol(lhsCopy);
+                        lhsCopySetter.ExecuteSetDirect(lhsCapture);
+                    }
 
-                lhsValue = lhsCopy;
+                    lhsValue = lhsCopy;
+                }
 
                 using (ExpressionCaptureScope rhsCapture = new ExpressionCaptureScope(visitorContext, null))
                 {
diff --git a/Assets/UdonSharp/Editor/UdonSharpExpressionCapture.cs b/Assets/UdonSharp/Editor/UdonSharpExpressionCapture.cs
index 33ab92b1..0b4b1b6c 100644
--- a/Assets/UdonSharp/Editor/UdonSharpExpressionCapture.cs
+++ b/Assets/UdonSharp/Editor/UdonSharpExpressionCapture.cs
@@ -1414,6 +1414,11 @@ public System.Type GetReturnType(bool getUserType = false)
             }
         }
 
+        public bool DoesReturnIntermediateSymbol()
+        {
+            return !IsLocalSymbol();
+        }
+
         public bool ResolveAccessToken(string accessToken)
         {
             bool resolvedToken = false;