feat: shift operators

vyper/ast/nodes.py

@@ -1036,6 +1036,20 @@ class BitXor(VyperNode):
     _op = operator.xor
 
 
+class LShift(VyperNode):
+    __slots__ = ()
+    _description = "bitwise left shift"
+    _pretty = "<<"
+    _op = operator.lshift
+
+
+class RShift(VyperNode):
+    __slots__ = ()
+    _description = "bitwise right shift"
+    _pretty = ">>"
+    _op = operator.rshift
+
+
 class BoolOp(VyperNode):
     __slots__ = ("op", "values")
 

vyper/ast/nodes.pyi

@@ -150,6 +150,8 @@ class Mult(VyperNode): ...
 class Div(VyperNode): ...
 class Mod(VyperNode): ...
 class Pow(VyperNode): ...
+class LShift(VyperNode): ...
+class RShift(VyperNode): ...
 class BoolOp(VyperNode): ...
 class And(VyperNode): ...
 class Or(VyperNode): ...

vyper/builtin_functions/functions.py

@@ -1441,8 +1441,13 @@ class Shift(BuiltinFunction):
         ("x", (Uint256Definition(), Int256Definition())),
         ("shift_bits", SignedIntegerAbstractType()),
     ]
+    _warned = False
 
     def evaluate(self, node):
+        if not self.__class__._warned:
+            vyper_warn("`shift()` is deprecated! Please use the << or >> operator instead.")
+            self.__class__._warned = True
+
         validate_call_args(node, 2)
         if [i for i in node.args if not isinstance(i, vy_ast.Num)]:
             raise UnfoldableNode

vyper/codegen/expr.py

@@ -13,6 +13,9 @@
     getpos,
     make_setter,
     pop_dyn_array,
+    sar,
+    shl,
+    shr,
     unwrap_location,
 )
 from vyper.codegen.ir_node import IRnode
@@ -368,6 +371,15 @@ def parse_BinOp(self):
             new_typ = left.typ
             return IRnode.from_list(["xor", left, right], typ=new_typ)
 
+        if isinstance(self.expr.op, vy_ast.LShift):
+            new_typ = left.typ
+            return IRnode.from_list(shl(right, left), typ=new_typ)
+        if isinstance(self.expr.op, vy_ast.RShift):
+            new_typ = left.typ
+            op = shr if not left.typ._int_info.is_signed else sar
+            # note: sar NotImplementedError for pre-constantinople
+            return IRnode.from_list(op(right, left), typ=new_typ)
+
         out_typ = BaseType(ltyp)
 
         with left.cache_when_complex("x") as (b1, x), right.cache_when_complex("y") as (b2, y):

vyper/semantics/types/value/numeric.py

@@ -37,6 +37,11 @@ def validate_numeric_op(
         if self._invalid_op and isinstance(node.op, self._invalid_op):
             raise InvalidOperation(f"Cannot perform {node.op.description} on {self}", node)
 
+        if isinstance(node.op, (vy_ast.LShift, vy_ast.RShift)) and self._bits != 256:
+            raise InvalidOperation(
+                f"Cannot perform {node.op.description} on non-int256/uint256 type!", node
+            )
+
         if isinstance(node.op, vy_ast.Pow):
             if isinstance(node, vy_ast.BinOp):
                 left, right = node.left, node.right