cxxrtl: allow customizing the root module path in the C API.

2 files changed, 20 insertions, 1 deletions

diff --git a/backends/cxxrtl/cxxrtl_capi.cc b/backends/cxxrtl/cxxrtl_capi.cc
index 1c3c63e3e..f92709b46 100644
--- a/backends/cxxrtl/cxxrtl_capi.cc
+++ b/backends/cxxrtl/cxxrtl_capi.cc
@@ -32,9 +32,22 @@ const cxxrtl::debug_items &cxxrtl_debug_items_from_handle(cxxrtl_handle handle)
 }
 
 cxxrtl_handle cxxrtl_create(cxxrtl_toplevel design) {
+	return cxxrtl_create_at(design, "");
+}
+
+cxxrtl_handle cxxrtl_create_at(cxxrtl_toplevel design, const char *root) {
+	std::string path = root;
+	if (!path.empty()) {
+		// module::debug_info() accepts either an empty path, or a path ending in space to simplify
+		// the logic in generated code. While this is sketchy at best to expose in the C++ API, this
+		// would be a lot worse in the C API, so don't expose it here.
+		assert(path.back() != ' ');
+		path += ' ';
+	}
+
 	cxxrtl_handle handle = new _cxxrtl_handle;
 	handle->module = std::move(design->module);
-	handle->module->debug_info(handle->objects);
+	handle->module->debug_info(handle->objects, path);
 	delete design;
 	return handle;
 }
diff --git a/backends/cxxrtl/cxxrtl_capi.h b/backends/cxxrtl/cxxrtl_capi.h
index 662bf2c20..d67c58f94 100644
--- a/backends/cxxrtl/cxxrtl_capi.h
+++ b/backends/cxxrtl/cxxrtl_capi.h
@@ -52,6 +52,12 @@ typedef struct _cxxrtl_handle *cxxrtl_handle;
 // The `design` is consumed by this operation and cannot be used afterwards.
 cxxrtl_handle cxxrtl_create(cxxrtl_toplevel design);
 
+// Create a design handle at a given hierarchy position from a design toplevel.
+//
+// This operation is similar to `cxxrtl_create`, except the full hierarchical name of every object
+// is prepended with `root`.
+cxxrtl_handle cxxrtl_create_at(cxxrtl_toplevel design, const char *root);
+
 // Release all resources used by a design and its handle.
 void cxxrtl_destroy(cxxrtl_handle handle);