[mypyc] feat: specialize isinstance for tuple of primitive types

Author: BobTheBuidler

mypyc/irbuild/specialize.py

@@ -31,6 +31,7 @@
     RefExpr,
     StrExpr,
     SuperExpr,
+    SymbolNode,
     TupleExpr,
     Var,
 )
@@ -587,18 +588,66 @@ def translate_isinstance(builder: IRBuilder, expr: CallExpr, callee: RefExpr) ->
     if not (len(expr.args) == 2 and expr.arg_kinds == [ARG_POS, ARG_POS]):
         return None
 
-    if isinstance(expr.args[1], (RefExpr, TupleExpr)):
-        builder.types[expr.args[0]] = AnyType(TypeOfAny.from_error)
-
-        irs = builder.flatten_classes(expr.args[1])
+    obj_expr = expr.args[0]
+    type_expr = expr.args[1]
+    
+    if isinstance(type_expr, TupleExpr) and not type_expr.items:
+        # we can compile this case to a noop
+        return builder.false()
+    
+    if isinstance(type_expr, (RefExpr, TupleExpr)):
+        builder.types[obj_expr] = AnyType(TypeOfAny.from_error)
+
+        irs = builder.flatten_classes(type_expr)
         if irs is not None:
             can_borrow = all(
                 ir.is_ext_class and not ir.inherits_python and not ir.allow_interpreted_subclasses
                 for ir in irs
             )
-            obj = builder.accept(expr.args[0], can_borrow=can_borrow)
+            obj = builder.accept(obj_expr, can_borrow=can_borrow)
             return builder.builder.isinstance_helper(obj, irs, expr.line)
 
+    if isinstance(type_expr, TupleExpr):
+        nodes: list[SymbolNode | None] = []
+        for item in type_expr.items:
+            if not isinstance(item, RefExpr):
+                return None
+            if item.node is None:
+                return None
+            if item.node.fullname not in nodes:
+                nodes.append(item.node.fullname)
+
+        descs = [isinstance_primitives.get(fullname) for fullname in nodes]
+    
+        obj = builder.accept(expr.args[0])
+
+        retval = Register(bool_rprimitive)
+        pass_block = BasicBlock()
+        fail_block = BasicBlock()
+        exit_block = BasicBlock()
+
+        # Chain the checks: if any succeed, jump to pass_block; else, continue
+        for i, desc in enumerate(descs):
+            is_last = (i == len(descs) - 1)
+            next_block = fail_block if is_last else BasicBlock()
+            builder.add_bool_branch(builder.primitive_op(desc, [obj], expr.line), pass_block, next_block)
+            if not is_last:
+                builder.activate_block(next_block)
+
+        # If any check passed
+        builder.activate_block(pass_block)
+        builder.assign(retval, builder.true(), expr.line)
+        builder.goto(exit_block)
+
+        # If all checks failed
+        builder.activate_block(fail_block)
+        builder.assign(retval, builder.false(), expr.line)
+        builder.goto(exit_block)
+
+        # Return the result
+        builder.activate_block(exit_block)
+        return retval
+
     if isinstance(expr.args[1], RefExpr):
         node = expr.args[1].node
         if node: