clean up types a bit

loopy/kernel/function_interface.py

@@ -348,8 +348,7 @@ def __init__(self,
         try:
             hash(arg_id_to_dtype)
         except TypeError:
-            if arg_id_to_dtype is None:
-                arg_id_to_dtype = {}
+            assert arg_id_to_dtype is not None
             arg_id_to_dtype = constantdict(arg_id_to_dtype)
             warn("arg_id_to_dtype passed to InKernelCallable was not hashable. "
                  "This usage is deprecated and will stop working in 2026.",
@@ -358,8 +357,7 @@ def __init__(self,
         try:
             hash(arg_id_to_descr)
         except TypeError:
-            if arg_id_to_descr is None:
-                arg_id_to_descr = {}
+            assert arg_id_to_descr is not None
             arg_id_to_descr = constantdict(arg_id_to_descr)
             warn("arg_id_to_descr passed to InKernelCallable was not hashable. "
                  "This usage is deprecated and will stop working in 2026.",

loopy/target/c/c_execution.py

@@ -31,6 +31,9 @@
 from typing import TYPE_CHECKING, Any, Callable, ClassVar, Sequence
 
 import numpy as np
+
+from constantdict import constantdict
+
 from codepy.jit import compile_from_string
 from codepy.toolchain import GCCToolchain, ToolchainGuessError, guess_toolchain
 
@@ -500,7 +503,7 @@ def get_wrapper_generator(self):
 
     @memoize_method
     def translation_unit_info(self,
-            arg_to_dtype: Mapping[str, LoopyType] | None = None) -> _KernelInfo:
+            arg_to_dtype: constantdict[str, LoopyType] | None = None) -> _KernelInfo:
         t_unit = self.get_typed_and_scheduled_translation_unit(arg_to_dtype)
 
         from loopy.codegen import generate_code_v2

loopy/target/execution.py

@@ -817,7 +817,7 @@ def check_for_required_array_arguments(self, input_args):
                 "your argument.")
 
     def get_typed_and_scheduled_translation_unit_uncached(
-            self, arg_to_dtype: Mapping[str, LoopyType] | None
+            self, arg_to_dtype: constantdict[str, LoopyType] | None
             ) -> TranslationUnit:
         t_unit = self.t_unit
 
@@ -827,15 +827,15 @@ def get_typed_and_scheduled_translation_unit_uncached(
             # FIXME: This is not so nice. This transfers types from the
             # subarrays of sep-tagged arrays to the 'main' array, because
             # type inference fails otherwise.
-            mm = dict(arg_to_dtype)
+            mm = arg_to_dtype.mutate()
             for name, sep_info in self.sep_info.items():
                 if entry_knl.arg_dict[name].dtype is None:
                     for sep_name in sep_info.subarray_names.values():
                         if sep_name in arg_to_dtype:
                             mm[name] = arg_to_dtype[sep_name]
                             del mm[sep_name]
 
-            arg_to_dtype = constantdict(mm)
+            arg_to_dtype = mm.finish()
 
             from loopy.kernel.tools import add_dtypes
             t_unit = t_unit.with_kernel(add_dtypes(entry_knl, arg_to_dtype))
@@ -854,7 +854,7 @@ def get_typed_and_scheduled_translation_unit_uncached(
         return t_unit
 
     def get_typed_and_scheduled_translation_unit(
-            self, arg_to_dtype: Mapping[str, LoopyType] | None
+            self, arg_to_dtype: constantdict[str, LoopyType] | None
             ) -> TranslationUnit:
         from loopy import CACHING_ENABLED
 
@@ -904,7 +904,7 @@ def get_highlighted_code(self, entrypoint, arg_to_dtype=None, code=None):
 
     def get_code(
             self, entrypoint: str,
-            arg_to_dtype: Mapping[str, LoopyType] | None = None) -> str:
+            arg_to_dtype: constantdict[str, LoopyType] | None = None) -> str:
         kernel = self.get_typed_and_scheduled_translation_unit(arg_to_dtype)
 
         from loopy.codegen import generate_code_v2

loopy/target/pyopencl_execution.py

@@ -30,6 +30,8 @@
 
 import numpy as np
 
+from constantdict import constantdict
+
 from pytools import memoize_method
 from pytools.codegen import CodeGenerator, Indentation
 
@@ -311,7 +313,7 @@ def get_wrapper_generator(self):
     @memoize_method
     def translation_unit_info(
             self,
-            arg_to_dtype: Mapping[str, LoopyType] | None = None) -> _KernelInfo:
+            arg_to_dtype: constantdict[str, LoopyType] | None = None) -> _KernelInfo:
         t_unit = self.get_typed_and_scheduled_translation_unit(arg_to_dtype)
 
         # FIXME: now just need to add the types to the arguments