[mypyc] Modify specializers and add int.__pow__ in test-data/fixture (#…

…10448)

* Move simple tuple and list creation to new functions. Each specializer only 
  focus on one situation now.
* Add int.__pow__ in test-data/fixture

mypyc/irbuild/specialize.py

@@ -97,19 +97,6 @@ def dict_methods_fast_path(
     if not (len(expr.args) == 1 and expr.arg_kinds == [ARG_POS]):
         return None
     arg = expr.args[0]
-
-    # Special case for simplest list comprehension, for example
-    #     list(x for x in tmp_list)
-    # TODO: The following code should be moved to a new function after
-    #       supporting multiple specialize functions
-    if not isinstance(callee, MemberExpr) and isinstance(arg, GeneratorExpr):
-        val = sequence_from_generator_preallocate_helper(
-            builder, arg,
-            empty_op_llbuilder=builder.builder.new_list_op_with_length,
-            set_item_op=new_list_set_item_op)
-        if val is not None:
-            return val
-
     if not (isinstance(arg, CallExpr) and not arg.args
             and isinstance(arg.callee, MemberExpr)):
         return None
@@ -130,6 +117,38 @@ def dict_methods_fast_path(
         return builder.call_c(dict_items_op, [obj], expr.line)
 
 
+@specialize_function('builtins.list')
+def translate_list_from_generator_call(
+        builder: IRBuilder, expr: CallExpr, callee: RefExpr) -> Optional[Value]:
+    # Special case for simplest list comprehension, for example
+    #     list(f(x) for x in other_list/other_tuple)
+    # translate_list_comprehension() would take care of other cases if this fails.
+    if (len(expr.args) == 1
+            and expr.arg_kinds[0] == ARG_POS
+            and isinstance(expr.args[0], GeneratorExpr)):
+        return sequence_from_generator_preallocate_helper(
+            builder, expr.args[0],
+            empty_op_llbuilder=builder.builder.new_list_op_with_length,
+            set_item_op=new_list_set_item_op)
+    return None
+
+
+@specialize_function('builtins.tuple')
+def translate_tuple_from_generator_call(
+        builder: IRBuilder, expr: CallExpr, callee: RefExpr) -> Optional[Value]:
+    # Special case for simplest tuple creation from a generator, for example
+    #     tuple(f(x) for x in other_list/other_tuple)
+    # translate_safe_generator_call() would take care of other cases if this fails.
+    if (len(expr.args) == 1
+            and expr.arg_kinds[0] == ARG_POS
+            and isinstance(expr.args[0], GeneratorExpr)):
+        return sequence_from_generator_preallocate_helper(
+            builder, expr.args[0],
+            empty_op_llbuilder=builder.builder.new_tuple_with_length,
+            set_item_op=new_tuple_set_item_op)
+    return None
+
+
 @specialize_function('builtins.set')
 def translate_set_from_generator_call(
         builder: IRBuilder, expr: CallExpr, callee: RefExpr) -> Optional[Value]:
@@ -168,14 +187,6 @@ def translate_safe_generator_call(
                     + [builder.accept(arg) for arg in expr.args[1:]]),
                 builder.node_type(expr), expr.line, expr.arg_kinds, expr.arg_names)
         else:
-            if len(expr.args) == 1 and callee.fullname == "builtins.tuple":
-                val = sequence_from_generator_preallocate_helper(
-                    builder, expr.args[0],
-                    empty_op_llbuilder=builder.builder.new_tuple_with_length,
-                    set_item_op=new_tuple_set_item_op)
-                if val is not None:
-                    return val
-
             return builder.call_refexpr_with_args(
                 expr, callee,
                 ([translate_list_comprehension(builder, expr.args[0])]

mypyc/test-data/fixtures/ir.py

@@ -34,6 +34,7 @@ def __init__(self, x: object, base: int = 10) -> None: pass
     def __add__(self, n: int) -> int: pass
     def __sub__(self, n: int) -> int: pass
     def __mul__(self, n: int) -> int: pass
+    def __pow__(self, n: int, modulo: Optional[int] = None) -> int: pass
     def __floordiv__(self, x: int) -> int: pass
     def __mod__(self, x: int) -> int: pass
     def __neg__(self) -> int: pass

mypyc/test-data/run-lists.test

@@ -354,3 +354,6 @@ def test() -> None:
     source_d = [True, False]
     d = [not x for x in source_d]
     assert d == [False, True]
+    source_e = [0, 1, 2]
+    e = list((x ** 2) for x in (y + 2 for y in source_e))
+    assert e == [4, 9, 16]