From a0e17df420ac0edf67368bc459275560d6470108 Mon Sep 17 00:00:00 2001
From: Kaushik Kulkarni <kaushikcfd@gmail.com>
Date: Thu, 14 Jul 2022 11:32:26 -0500
Subject: [PATCH] require targets to provide whether they are executable

---
 loopy/target/__init__.py   |  8 ++++++++
 loopy/target/c/__init__.py | 12 +++++++++++-
 loopy/target/cuda.py       |  4 ++++
 loopy/target/ispc.py       | 10 ++++++++--
 loopy/target/opencl.py     |  4 ++++
 loopy/target/pyopencl.py   |  4 ++++
 6 files changed, 39 insertions(+), 3 deletions(-)

diff --git a/loopy/target/__init__.py b/loopy/target/__init__.py
index 5bb1043b9..572c0e95f 100644
--- a/loopy/target/__init__.py
+++ b/loopy/target/__init__.py
@@ -49,6 +49,7 @@
 
 from typing import (Any, Tuple, Generic, TypeVar, Sequence, ClassVar, Optional,
         TYPE_CHECKING)
+import abc
 
 if TYPE_CHECKING:
     from loopy.typing import ExpressionT
@@ -159,6 +160,13 @@ def get_kernel_executor(self, kernel, *args, **kwargs):
         """
         raise NotImplementedError()
 
+    @abc.abstractproperty
+    def is_executable(self) -> bool:
+        """
+        Returns *True* only if the target allows executing loopy
+        translation units through :attr:`loopy.TranslationUnit.__call__`.
+        """
+
 
 class ASTBuilderBase(Generic[ASTType]):
     """An interface for generating (host or device) ASTs.
diff --git a/loopy/target/c/__init__.py b/loopy/target/c/__init__.py
index de6a32a68..7a3588373 100644
--- a/loopy/target/c/__init__.py
+++ b/loopy/target/c/__init__.py
@@ -841,7 +841,9 @@ def get_function_declaration(
             # subkernel launches occur only as part of entrypoint kernels for now
             from loopy.schedule.tools import get_subkernel_arg_info
             skai = get_subkernel_arg_info(kernel, subkernel_name)
-            passed_names = skai.passed_names
+            passed_names = (skai.passed_names
+                            if self.target.is_executable
+                            else [arg.name for arg in kernel.args])
             written_names = skai.written_names
         else:
             name = Value("static void", name)
@@ -1333,6 +1335,10 @@ def get_dtype_registry(self):
         fill_registry_with_c99_complex_types(result)
         return DTypeRegistryWrapper(result)
 
+    @property
+    def is_executable(self) -> bool:
+        return False
+
 
 class CASTBuilder(CFamilyASTBuilder):
     def preamble_generators(self):
@@ -1376,6 +1382,10 @@ def get_host_ast_builder(self):
         # enable host code generation
         return CFamilyASTBuilder(self)
 
+    @property
+    def is_executable(self) -> bool:
+        return True
+
 # }}}
 
 
diff --git a/loopy/target/cuda.py b/loopy/target/cuda.py
index 4a311f887..5254b08dc 100644
--- a/loopy/target/cuda.py
+++ b/loopy/target/cuda.py
@@ -255,6 +255,10 @@ def vector_dtype(self, base, count):
 
     # }}}
 
+    @property
+    def is_executable(self) -> bool:
+        return False
+
 # }}}
 
 
diff --git a/loopy/target/ispc.py b/loopy/target/ispc.py
index 2fbd6bcf8..385fcf9f8 100644
--- a/loopy/target/ispc.py
+++ b/loopy/target/ispc.py
@@ -198,6 +198,10 @@ def get_dtype_registry(self):
 
     # }}}
 
+    @property
+    def is_executable(self) -> bool:
+        return False
+
 
 class ISPCASTBuilder(CFamilyASTBuilder):
     # {{{ top-level codegen
@@ -222,7 +226,9 @@ def get_function_declaration(
             # subkernel launches occur only as part of entrypoint kernels for now
             from loopy.schedule.tools import get_subkernel_arg_info
             skai = get_subkernel_arg_info(codegen_state.kernel, subkernel_name)
-            passed_names = skai.passed_names
+            passed_names = (skai.passed_names
+                            if self.target.is_executable
+                            else [arg.name for arg in kernel.args])
             written_names = skai.written_names
         else:
             passed_names = [arg.name for arg in kernel.args]
@@ -263,7 +269,7 @@ def get_kernel_call(self, codegen_state: CodeGenerationState,
                         "assert(programCount == (%s))"
                         % ecm(lsize[0], PREC_NONE)))
 
-        if codegen_state.is_entrypoint:
+        if codegen_state.is_entrypoint and self.target.is_executable:
             # subkernel launches occur only as part of entrypoint kernels for now
             from loopy.schedule.tools import get_subkernel_arg_info
             skai = get_subkernel_arg_info(codegen_state.kernel, subkernel_name)
diff --git a/loopy/target/opencl.py b/loopy/target/opencl.py
index 6957d3f96..37bee3856 100644
--- a/loopy/target/opencl.py
+++ b/loopy/target/opencl.py
@@ -598,6 +598,10 @@ def is_vector_dtype(self, dtype):
     def vector_dtype(self, base, count):
         return NumpyType(vec.types[base.numpy_dtype, count])
 
+    @property
+    def is_executable(self) -> bool:
+        return False
+
 # }}}
 
 
diff --git a/loopy/target/pyopencl.py b/loopy/target/pyopencl.py
index cb78e571b..641a40bef 100644
--- a/loopy/target/pyopencl.py
+++ b/loopy/target/pyopencl.py
@@ -551,6 +551,10 @@ def with_device(self, device):
                 "stop working in 2022.", DeprecationWarning, stacklevel=2)
         return self
 
+    @property
+    def is_executable(self) -> bool:
+        return True
+
 # }}}