update sv int

src/peakrdl_busdecoder/sv_int.py

@@ -1,8 +1,15 @@
+from typing import Literal
+
+
 class SVInt:
     def __init__(self, value: int, width: int | None = None) -> None:
         self.value = value
         self.width = width
 
+        if width is not None:
+            self.width = max(width, self.value.bit_length())
+        # assert (width is None) or (self.value.bit_length() <= width), "Value does not fit in specified width"
+
     def __str__(self) -> str:
         if self.width is not None:
             # Explicit width
@@ -19,3 +26,27 @@ class SVInt:
             return SVInt(self.value + other.value, max(self.width, other.width))
         else:
             return SVInt(self.value + other.value, None)
+
+    def __sub__(self, other: "SVInt") -> "SVInt":
+        if self.width is not None and other.width is not None:
+            return SVInt(self.value - other.value, max(self.width, other.width))
+        else:
+            return SVInt(self.value - other.value, None)
+
+    def __len__(self) -> int:
+        if self.width is not None:
+            return self.width
+        else:
+            return self.value.bit_length()
+
+    def to_bytes(self, byteorder: Literal["little", "big"] = "little") -> bytes:
+        byte_length = (self.value.bit_length() + 7) // 8
+        return self.value.to_bytes(byte_length, byteorder)
+
+    def __eq__(self, other: object) -> bool:
+        if not isinstance(other, SVInt):
+            return NotImplemented
+        return self.value == other.value and self.width == other.width 
+    
+    def __hash__(self) -> int:
+        return hash((self.value, self.width))