Reduces LUT needed by mul extension

src/main/scala/projet/Utils.scala

@@ -0,0 +1,15 @@
+package projet
+
+import chisel3._
+
+object Utils {
+    def two_complement(x: UInt, word_sized: Bool = false.B): UInt = {
+        val result = Wire(UInt(64.W))
+        when(word_sized) {
+            result := "xFFFFFFFF".U - x + 1.U
+        }.otherwise {
+            result := "xFFFFFFFFFFFFFFFF".U - x + 1.U
+        }
+        result
+    }
+}