Add safety check to generated kernels

codegen/gen.py

@@ -243,6 +243,10 @@ def __call__(
             argument_type_gen=argument_type_gen
         ).convert_arguments(arguments)
 
+        # +1 for the return value
+        num_boxed_args = len(binding_list) + 1
+        # This safety check does not account for optional args with default values. ET itself doesnt support default args, but when supported is added this check can be relaxed to >= # of non default arg.
+        safety_check = f"""ET_KERNEL_CHECK_MSG(context, stack.size() == {num_boxed_args}, InvalidProgram, /*void*/, \"Expected %\" ET_PRIsize_t \"args received %\" ET_PRIsize_t, (size_t){num_boxed_args}, stack.size());"""
         # for each C++ argument, generate the conversion code
         code_connector = "\n\t"
         arg_connector = ", "
@@ -292,12 +296,13 @@ def __call__(
 {indent}  context.fail(torch::executor::Error::Internal);
 {indent}}}"""
         newline = "\n    "
-        return "\n".join(
+        temp = "\n".join(
             [
                 f"""
 Kernel(
     "{f.namespace}::{f.func.name}",{newline + '"' + (k + '",') if k != "default" else ""}
     []({contextArg.defn()}, Span<EValue*> stack) {{
+        {safety_check}
         {code_connector.join(code_list)}
 
 {exception_boundary_begin}
@@ -313,6 +318,7 @@ def __call__(
                 for k in used_kernel_keys
             ]
         )
+        return temp
 
 
 def gen_unboxing(
@@ -534,6 +540,7 @@ def gen_headers(
         "headers": [
             "#include <executorch/runtime/core/exec_aten/exec_aten.h> // at::Tensor etc.",
             "#include <executorch/runtime/kernel/kernel_runtime_context.h>",
+            "#include <executorch/runtime/core/error.h>",
         ],
     }
     if use_aten_lib:

codegen/templates/RegisterCodegenUnboxedKernels.cpp

@@ -8,6 +8,7 @@
 
 #include <executorch/runtime/core/evalue.h>
 #include <executorch/runtime/core/exec_aten/exec_aten.h>
+#include <executorch/runtime/core/exec_aten/util/tensor_util.h>
 #include <executorch/runtime/core/span.h>
 #include <executorch/runtime/kernel/operator_registry.h>
 #include <executorch/runtime/platform/profiler.h>

codegen/templates/RegisterKernels.cpp

@@ -10,6 +10,7 @@
 // This implements register_all_kernels() API that is declared in
 // RegisterKernels.h
 #include "RegisterKernels.h"
+#include <executorch/runtime/core/exec_aten/util/tensor_util.h>
 #include "${fn_header}" // Generated Function import headers
 
 namespace torch {

codegen/test/test_executorch_gen.py

@@ -508,6 +508,7 @@ def test_codegen_unboxed_specialized(self) -> None:
     "custom_1::op_1",
     "v1/7;0,1,2,3|7;0,1,2,3|7;0,1,2,3",
     [](torch::executor::KernelRuntimeContext & context, Span<EValue*> stack) {
+        ET_KERNEL_CHECK_MSG(context, stack.size() == 1, InvalidProgram, /*void*/, \"Expected %\" ET_PRIsize_t \"args received %\" ET_PRIsize_t, (size_t)1, stack.size());
         """
             + """
 
@@ -606,6 +607,7 @@ def test_codegen_unboxed_default(self) -> None:
 Kernel(
     "custom_1::op_1",
     [](torch::executor::KernelRuntimeContext & context, Span<EValue*> stack) {
+        ET_KERNEL_CHECK_MSG(context, stack.size() == 1, InvalidProgram, /*void*/, \"Expected %\" ET_PRIsize_t \"args received %\" ET_PRIsize_t, (size_t)1, stack.size());
         """
             + """
 
@@ -621,7 +623,6 @@ def test_codegen_unboxed_default(self) -> None:
 ),
 """
         )
-
         self.assertEqual(expected_str, result)
 
         result = ComputeCodegenUnboxedKernels(
@@ -633,6 +634,7 @@ def test_codegen_unboxed_default(self) -> None:
 Kernel(
     "custom_1::op_1",
     [](torch::executor::KernelRuntimeContext & context, Span<EValue*> stack) {
+        ET_KERNEL_CHECK_MSG(context, stack.size() == 1, InvalidProgram, /*void*/, "Expected %" ET_PRIsize_t "args received %" ET_PRIsize_t, (size_t)1, stack.size());
         """
             + """
 
@@ -676,6 +678,7 @@ def test_codegen_unboxed_default_kernel_key_selected(self) -> None:
 Kernel(
     "custom_1::op_1",
     [](torch::executor::KernelRuntimeContext & context, Span<EValue*> stack) {
+        ET_KERNEL_CHECK_MSG(context, stack.size() == 1, InvalidProgram, /*void*/, "Expected %" ET_PRIsize_t "args received %" ET_PRIsize_t, (size_t)1, stack.size());
         """
             + """
 

shim_et/xplat/executorch/codegen/codegen.bzl

@@ -896,6 +896,7 @@ def executorch_generated_lib(
             exported_deps = [
                 "//executorch/codegen:macros",
                 "//executorch/runtime/kernel:kernel_runtime_context" + aten_suffix,
+                "//executorch/runtime/core/exec_aten/util:tensor_util" + aten_suffix,
             ],
             feature = feature,
         )
@@ -933,6 +934,7 @@ def executorch_generated_lib(
             exported_deps = [
                 "//executorch/runtime/core/exec_aten:lib" + aten_suffix,
                 "//executorch/runtime/kernel:kernel_runtime_context" + aten_suffix,
+                "//executorch/runtime/core/exec_aten/util:tensor_util" + aten_suffix,
             ],
             xplat_deps = xplat_deps,
             fbcode_deps = fbcode_deps,