[slimtensor] Add utility functions to common_shims_slim

backends/aoti/common_shims_slim.h

@@ -288,6 +288,65 @@ inline AOTITorchError aoti_torch_get_device_index(
   return Error::Ok;
 }
 
+// ============================================================
+// DType Constants - These return PyTorch ScalarType enum values
+// ============================================================
+
+inline int32_t aoti_torch_dtype_float32() {
+  return 6; // ScalarType::Float
+}
+
+inline int32_t aoti_torch_dtype_bfloat16() {
+  return 15; // ScalarType::BFloat16
+}
+
+inline int32_t aoti_torch_dtype_int64() {
+  return 4; // ScalarType::Long
+}
+
+inline int32_t aoti_torch_dtype_int32() {
+  return 3; // ScalarType::Int
+}
+
+inline int32_t aoti_torch_dtype_int16() {
+  return 2; // ScalarType::Short
+}
+
+inline int32_t aoti_torch_dtype_int8() {
+  return 1; // ScalarType::Char
+}
+
+inline int32_t aoti_torch_dtype_bool() {
+  return 11; // ScalarType::Bool
+}
+
+// ============================================================
+// Device Type Constants
+// ============================================================
+
+inline int32_t aoti_torch_device_type_cpu() {
+  return 0; // DeviceType::CPU
+}
+
+inline int32_t aoti_torch_device_type_cuda() {
+  return 1; // DeviceType::CUDA
+}
+
+// ============================================================
+// Grad Mode Functions (not supported in ExecuTorch)
+// ============================================================
+
+inline bool aoti_torch_grad_mode_is_enabled() {
+  return false; // ExecuTorch doesn't support autograd
+}
+
+inline AOTITorchError aoti_torch_grad_mode_set_enabled(bool enabled) {
+  if (enabled) {
+    return Error::NotSupported; // Grad mode not supported in ExecuTorch
+  }
+  return Error::Ok;
+}
+
 } // namespace aoti
 } // namespace backends
 } // namespace executorch

backends/aoti/tests/test_common_shims_slim.cpp

@@ -589,3 +589,44 @@ TEST_F(CommonShimsSlimTest, ConsistentPointerReturn) {
   EXPECT_EQ(aoti_torch_get_strides(tensor, &strides_ptr2), Error::Ok);
   EXPECT_EQ(strides_ptr1, strides_ptr2);
 }
+
+// ============================================================================
+// DType Constants Tests
+// ============================================================================
+
+TEST_F(CommonShimsSlimTest, DTypeConstants) {
+  // Verify dtype constants match expected PyTorch ScalarType values
+  EXPECT_EQ(aoti_torch_dtype_float32(), 6); // ScalarType::Float
+  EXPECT_EQ(aoti_torch_dtype_bfloat16(), 15); // ScalarType::BFloat16
+  EXPECT_EQ(aoti_torch_dtype_int64(), 4); // ScalarType::Long
+  EXPECT_EQ(aoti_torch_dtype_int32(), 3); // ScalarType::Int
+  EXPECT_EQ(aoti_torch_dtype_int16(), 2); // ScalarType::Short
+  EXPECT_EQ(aoti_torch_dtype_int8(), 1); // ScalarType::Char
+  EXPECT_EQ(aoti_torch_dtype_bool(), 11); // ScalarType::Bool
+}
+
+// ============================================================================
+// Device Type Constants Tests
+// ============================================================================
+
+TEST_F(CommonShimsSlimTest, DeviceTypeConstants) {
+  EXPECT_EQ(aoti_torch_device_type_cpu(), 0); // DeviceType::CPU
+  EXPECT_EQ(aoti_torch_device_type_cuda(), 1); // DeviceType::CUDA
+}
+
+// ============================================================================
+// Grad Mode Tests
+// ============================================================================
+
+TEST_F(CommonShimsSlimTest, GradModeIsEnabled) {
+  // ExecuTorch doesn't support autograd, so should always return false
+  EXPECT_EQ(aoti_torch_grad_mode_is_enabled(), false);
+}
+
+TEST_F(CommonShimsSlimTest, GradModeSetEnabled) {
+  // Setting to false should succeed
+  EXPECT_EQ(aoti_torch_grad_mode_set_enabled(false), Error::Ok);
+
+  // Setting to true should fail (not supported in ExecuTorch)
+  EXPECT_EQ(aoti_torch_grad_mode_set_enabled(true), Error::NotSupported);
+}