diff --git a/src/HexManiac.Core/Models/Code/ThumbParser.cs b/src/HexManiac.Core/Models/Code/ThumbParser.cs
index 801a1bac..3e1c2621 100644
--- a/src/HexManiac.Core/Models/Code/ThumbParser.cs
+++ b/src/HexManiac.Core/Models/Code/ThumbParser.cs
@@ -782,6 +782,7 @@ namespace HavenSoft.HexManiac.Core.Models.Code {
                   for (int index = 0; index < instructionParts.Count; index++) {
                      var instruction = instructionParts[index];
                      if (instruction.Name != name) continue;
+                     if (registerValues.ContainsKey(index) && registerValues[index] != value) return false;
                      registerValues[index] = value;
                   }
                }
diff --git a/src/HexManiac.Core/Models/Code/armReference.txt b/src/HexManiac.Core/Models/Code/armReference.txt
index 5cbbc3d6..44d2e206 100644
--- a/src/HexManiac.Core/Models/Code/armReference.txt
+++ b/src/HexManiac.Core/Models/Code/armReference.txt
@@ -42,6 +42,7 @@ nv=1111  @    never
 0001100 rm rn rd    |     add   rd, rn, rm    @ rd = rn + rm
 0001101 rm rn rd    |     sub   rd, rn, rm    @ rd = rn - rm
 0001110000 rn rd    |     mov   rd, rn        @ rd = rn
+00110 rd #          |     add   rd, rd, #     @ rd += # (alais)
 0001110 # rn rd     |     add   rd, rn, #     @ rd = rn + #
 0001111 # rn rd     |     sub   rd, rn, #     @ rd = rn - #
 00100 rd #          |     mov   rd, #         @ rd = #
diff --git a/src/HexManiac.Tests/Before_Baseclass/ToolTests.cs b/src/HexManiac.Tests/Before_Baseclass/ToolTests.cs
index eea4a0c7..ee198c10 100644
--- a/src/HexManiac.Tests/Before_Baseclass/ToolTests.cs
+++ b/src/HexManiac.Tests/Before_Baseclass/ToolTests.cs
@@ -375,6 +375,8 @@ namespace HavenSoft.HexManiac.Tests {
       [InlineData("add   r0, r1, r2", 0b0001100_010_001_000)]
       [InlineData("add   r0, r1",     0b0001100_001_000_000)]
       [InlineData("add   r8, r0",     0b1000100_1_0_000_000)]
+      [InlineData("add   r0, r1, #4", 0b0001110_100_001_000)]
+      [InlineData("add   r2, r2, #4", 0b00110_010_00000100)]
       [InlineData("lsl   r1, r2, #4", 0b00000_00100_010_001)]
       [InlineData("lsl   r1, #4",     0b00000_00100_001_001)]
       [InlineData("bls   <000120>", 0b1101_1001_00001110)]
diff --git a/src/HexManiac.Tests/CodeToolTests.cs b/src/HexManiac.Tests/CodeToolTests.cs
index 9053086d..ff1f735e 100644
--- a/src/HexManiac.Tests/CodeToolTests.cs
+++ b/src/HexManiac.Tests/CodeToolTests.cs
@@ -15,6 +15,9 @@ namespace HavenSoft.HexManiac.Tests {
          get => ";".Join(Tool.Contents[0].Content.SplitLines().Select(line => line.Trim()));
          set => Tool.Contents[0].Content = value.Replace(";", Environment.NewLine);
       }
+      private string ThumbScript {
+         set => Tool.Content = value.Replace(";", Environment.NewLine);
+      }
       private string GetContent(int index) => Tool.Contents[index].Content;
       private void SetContent(int index, string content) => Tool.Contents[index].Content = content.Replace(";", Environment.NewLine);
 
@@ -166,5 +169,11 @@ namespace HavenSoft.HexManiac.Tests {
          Assert.IsType<PointerRun>(Model.GetNextRun(5));
          Model.ResolveConflicts();
       }
+
+      [Fact]
+      public void AddWithTwoSameRegisters_AddWithOneRegister_SameCode() {
+         ThumbScript = "add r3,r3,#6; add r3, #6";
+         Assert.Equal(Model.ReadMultiByteValue(0, 2), Model.ReadMultiByteValue(2, 2));
+      }
    }
 }