[mono] Remove "old" sgen bridge (#67957)

We default to the tarjan bridge for quite a while now, so remove the "old" bridge. We decided to keep the "new" bridge since there are still a few usecases for it (some Xamarin.Android customers use it). If a user selects the "old" bridge we'll use the "new" bridge instead and print a warning.
dotnet · Apr 13, 2022 · c59e1c4 · c59e1c4
1 parent 12dd2ab
commit c59e1c4
Show file tree

Hide file tree

Showing 6 changed files with 3 additions and 948 deletions.
diff --git a/src/mono/mono/metadata/CMakeLists.txt b/src/mono/mono/metadata/CMakeLists.txt
@@ -181,7 +181,6 @@ if(MONO_GC STREQUAL "sgen")
     set(metadata_gc_sources
         sgen-bridge.c
         sgen-bridge-internals.h
-        sgen-old-bridge.c
         sgen-new-bridge.c
         sgen-tarjan-bridge.c
         sgen-toggleref.c

diff --git a/src/mono/mono/metadata/sgen-bridge-internals.h b/src/mono/mono/metadata/sgen-bridge-internals.h
@@ -69,7 +69,6 @@ typedef struct {
 	MonoGCBridgeXRef *api_xrefs;
 } SgenBridgeProcessor;
 
-void sgen_old_bridge_init (SgenBridgeProcessor *collector);
 void sgen_new_bridge_init (SgenBridgeProcessor *collector);
 void sgen_tarjan_bridge_init (SgenBridgeProcessor *collector);
 void sgen_set_bridge_implementation (const char *name);

diff --git a/src/mono/mono/metadata/sgen-bridge.c b/src/mono/mono/metadata/sgen-bridge.c
@@ -26,7 +26,6 @@
 
 typedef enum {
 	BRIDGE_PROCESSOR_INVALID,
-	BRIDGE_PROCESSOR_OLD,
 	BRIDGE_PROCESSOR_NEW,
 	BRIDGE_PROCESSOR_TARJAN,
 	BRIDGE_PROCESSOR_DEFAULT = BRIDGE_PROCESSOR_TARJAN
@@ -93,7 +92,8 @@ static BridgeProcessorSelection
 bridge_processor_name (const char *name)
 {
 	if (!strcmp ("old", name)) {
-		return BRIDGE_PROCESSOR_OLD;
+		g_warning ("The 'old' bridge processor implementation is no longer supported, falling back to the 'new' bridge.");
+		return BRIDGE_PROCESSOR_NEW;
 	} else if (!strcmp ("new", name)) {
 		return BRIDGE_PROCESSOR_NEW;
 	} else if (!strcmp ("tarjan", name)) {
@@ -116,9 +116,6 @@ init_bridge_processor (SgenBridgeProcessor *processor, BridgeProcessorSelection
 	memset (processor, 0, sizeof (SgenBridgeProcessor));
 
 	switch (selection) {
-		case BRIDGE_PROCESSOR_OLD:
-			sgen_old_bridge_init (processor);
-			break;
 		case BRIDGE_PROCESSOR_NEW:
 			sgen_new_bridge_init (processor);
 			break;
@@ -179,7 +176,7 @@ sgen_set_bridge_implementation (const char *name)
 	BridgeProcessorSelection selection = bridge_processor_name (name);
 
 	if (selection == BRIDGE_PROCESSOR_INVALID)
-		g_warning ("Invalid value for bridge processor implementation, valid values are: 'new', 'old' and 'tarjan'.");
+		g_warning ("Invalid value for bridge processor implementation, valid values are: 'new' or 'tarjan'.");
 	else if (bridge_processor_started ())
 		g_warning ("Cannot set bridge processor implementation once bridge has already started");
 	else