1 files changed, 34 insertions, 0 deletions
diff --git a/ARMeilleure/Decoders/OpCodeT16MemMult.cs b/ARMeilleure/Decoders/OpCodeT16MemMult.cs
new file mode 100644
index 00000000..f4185cfc
--- /dev/null
+++ b/ARMeilleure/Decoders/OpCodeT16MemMult.cs
@@ -0,0 +1,34 @@
+using ARMeilleure.Instructions;
+using System;
+using System.Numerics;
+
+namespace ARMeilleure.Decoders
+{
+    class OpCodeT16MemMult : OpCodeT16, IOpCode32MemMult
+    {
+        public int Rn { get; }
+        public int RegisterMask { get; }
+        public int PostOffset { get; }
+        public bool IsLoad { get; }
+        public int Offset { get; }
+
+        public new static OpCode Create(InstDescriptor inst, ulong address, int opCode) => new OpCodeT16MemMult(inst, address, opCode);
+
+        public OpCodeT16MemMult(InstDescriptor inst, ulong address, int opCode) : base(inst, address, opCode)
+        {
+            RegisterMask = opCode & 0xff;
+            Rn = (opCode >> 8) & 7;
+
+            int regCount = BitOperations.PopCount((uint)RegisterMask);
+
+            Offset = 0;
+            PostOffset = 4 * regCount;
+            IsLoad = inst.Name switch
+            {
+                InstName.Ldm => true,
+                InstName.Stm => false,
+                _ => throw new InvalidOperationException()
+            };
+        }
+    }
+}