From efac4c16ed7c020fc85215888b060b696dc15cca Mon Sep 17 00:00:00 2001
From: Vlad Brezae <brezaevlad@gmail.com>
Date: Wed, 30 Jan 2019 16:17:08 +0200
Subject: [PATCH] [sgen] Logging for objects kept alive from ephemerons
 (#12650)

---
 mono/metadata/sgen-client-mono.h | 5 +++++
 mono/metadata/sgen-mono.c        | 4 +++-
 mono/sgen/sgen-protocol-def.h    | 7 +++++++
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/mono/metadata/sgen-client-mono.h b/mono/metadata/sgen-client-mono.h
index b3773f8bb98..92d4e56c7c7 100644
--- a/mono/metadata/sgen-client-mono.h
+++ b/mono/metadata/sgen-client-mono.h
@@ -683,6 +683,11 @@ sgen_client_binary_protocol_collection_end_stats (long long major_scan, long lon
 {
 }
 
+static void G_GNUC_UNUSED
+sgen_client_binary_protocol_ephemeron_ref (gpointer list, gpointer key, gpointer val)
+{
+}
+
 #define TLAB_ACCESS_INIT	SgenThreadInfo *__thread_info__ = mono_tls_get_sgen_thread_info ()
 #define IN_CRITICAL_REGION (__thread_info__->client_info.in_critical_region)
 
diff --git a/mono/metadata/sgen-mono.c b/mono/metadata/sgen-mono.c
index 7476f7c78b1..4f078be119d 100644
--- a/mono/metadata/sgen-mono.c
+++ b/mono/metadata/sgen-mono.c
@@ -686,8 +686,10 @@ sgen_client_mark_ephemerons (ScanCopyContext ctx)
 
 				copy_func (&cur->key, queue);
 				if (value) {
-					if (!sgen_is_object_alive_for_current_gen (value))
+					if (!sgen_is_object_alive_for_current_gen (value)) {
 						nothing_marked = FALSE;
+						sgen_binary_protocol_ephemeron_ref (current, key, value);
+					}
 					copy_func (&cur->value, queue);
 				}
 			}
diff --git a/mono/sgen/sgen-protocol-def.h b/mono/sgen/sgen-protocol-def.h
index ecb12f857f2..cc1a860c25e 100644
--- a/mono/sgen/sgen-protocol-def.h
+++ b/mono/sgen/sgen-protocol-def.h
@@ -471,6 +471,13 @@ MATCH_INDEX (BINARY_PROTOCOL_MATCH)
 IS_VTABLE_MATCH (FALSE)
 END_PROTOCOL_ENTRY
 
+BEGIN_PROTOCOL_ENTRY_HEAVY3 (binary_protocol_ephemeron_ref, TYPE_POINTER, list, TYPE_POINTER, key, TYPE_POINTER, value)
+DEFAULT_PRINT ()
+IS_ALWAYS_MATCH (FALSE)
+MATCH_INDEX (ptr == entry->list ? 0 : ptr == entry->key ? 1 : ptr == entry->value ? 2 : BINARY_PROTOCOL_NO_MATCH)
+IS_VTABLE_MATCH (FALSE)
+END_PROTOCOL_ENTRY_HEAVY
+
 #undef BEGIN_PROTOCOL_ENTRY0
 #undef BEGIN_PROTOCOL_ENTRY1
 #undef BEGIN_PROTOCOL_ENTRY2
-- 
2.11.4.GIT