Skip graph export for newly added TF MLIR functions if backend_compil…

…er is not specified.

All the needed function defs are already in the function library if no special backend_compiler is used. This reduces the memory usage.

PiperOrigin-RevId: 628740418

tensorflow/compiler/mlir/tfrt/transforms/mlrt/import_model.cc

@@ -59,37 +59,39 @@ absl::StatusOr<mlrt::bc::Buffer> ConvertTfMlirToBytecode(
   mlrt::bc::Buffer bytecode_buffer;
   TF_RETURN_IF_ERROR(ConvertTfMlirToRuntimeExecutable(
       options, module,
-      [&bytecode_buffer, &fallback_state, &model_context, module_with_op_keys](
-          mlir::PassManager& pm, mlir::ModuleOp module,
-          const TfrtPipelineOptions& options) {
-        if (auto* flib_def = model_context.function_library_definition()) {
-          // Copy the module before exporting as exporting to graph will
-          // transform the MLIR to TFG dialect.
-          mlir::OwningOpRef<mlir::ModuleOp> copy(module.clone());
-          TF_RETURN_IF_ERROR(
-              ExportFunctionDefs(*copy, [flib_def](FunctionDef function_def) {
-                VLOG(1) << absl::StrCat(
-                    "Exporting MLIR function as function_def: ",
-                    // clang-tidy off
-                    function_def.DebugString()
-                    // clang-tidy on
-                );
+      [&bytecode_buffer, &fallback_state, &model_context,
+       backend_compiler = options.backend_compiler,
+       module_with_op_keys](mlir::PassManager& pm, mlir::ModuleOp module,
+                            const TfrtPipelineOptions& options) {
+        if (backend_compiler) {
+          if (auto* flib_def = model_context.function_library_definition()) {
+            // Copy the module before exporting as exporting to graph will
+            // transform the MLIR to TFG dialect.
+            mlir::OwningOpRef<mlir::ModuleOp> copy(module.clone());
+            TF_RETURN_IF_ERROR(
+                ExportFunctionDefs(*copy, [flib_def](FunctionDef function_def) {
+                  VLOG(1) << absl::StrCat(
+                      "Exporting MLIR function as function_def: ",
+                      // NOLINTNEXTLINE
+                      function_def.DebugString());
 
-                // The TF MLIR compiler may change the function name. Then we
-                // need to retrieve the original name from the
-                // _original_func_name attribute.
-                auto iter = function_def.attr().find("_original_func_name");
-                if (iter != function_def.attr().end()) {
-                  function_def.mutable_signature()->set_name(iter->second.s());
-                }
+                  // The TF MLIR compiler may change the function name. Then we
+                  // need to retrieve the original name from the
+                  // _original_func_name attribute.
+                  auto iter = function_def.attr().find("_original_func_name");
+                  if (iter != function_def.attr().end()) {
+                    function_def.mutable_signature()->set_name(
+                        iter->second.s());
+                  }
 
-                const auto& name = function_def.signature().name();
-                if (flib_def->Contains(name)) {
-                  TF_RETURN_IF_ERROR(flib_def->RemoveFunction(name));
-                }
+                  const auto& name = function_def.signature().name();
+                  if (flib_def->Contains(name)) {
+                    TF_RETURN_IF_ERROR(flib_def->RemoveFunction(name));
+                  }
 
-                return flib_def->AddFunctionDef(function_def);
-              }));
+                  return flib_def->AddFunctionDef(function_def);
+                }));
+          }
         }
 
         mlir::StatusScopedDiagnosticHandler diag_handler(module.getContext());