1 files changed, 57 insertions, 0 deletions

diff --git a/src/sim/serialize.cc b/src/sim/serialize.cc
index 0904b1375..f9a945b95 100644
--- a/src/sim/serialize.cc
+++ b/src/sim/serialize.cc
@@ -496,16 +496,73 @@ class Globals : public Serializable
 /// The one and only instance of the Globals class.
 Globals globals;
 
+/// The version tags for this build of the simulator, to be stored in the
+/// Globals section during serialization and compared upon unserialization.
+extern std::set<std::string> version_tags;
+
 void
 Globals::serialize(CheckpointOut &cp) const
 {
     paramOut(cp, "curTick", curTick());
+    SERIALIZE_CONTAINER(version_tags);
 }
 
 void
 Globals::unserialize(CheckpointIn &cp)
 {
     paramIn(cp, "curTick", unserializedCurTick);
+
+    const std::string &section(Serializable::currentSection());
+    std::string str;
+    if (!cp.find(section, "version_tags", str)) {
+        warn("**********************************************************\n");
+        warn("!!!! Checkpoint uses an old versioning scheme.        !!!!\n");
+        warn("Run the checkpoint upgrader (util/cpt_upgrader.py) on your "
+             "checkpoint\n");
+        warn("**********************************************************\n");
+        return;
+    }
+
+    std::set<std::string> cpt_tags;
+    arrayParamIn(cp, "version_tags", cpt_tags); // UNSERIALIZE_CONTAINER
+
+    bool err = false;
+    for (const auto& t : version_tags) {
+        if (cpt_tags.find(t) == cpt_tags.end()) {
+            // checkpoint is missing tag that this binary has
+            if (!err) {
+                warn("*****************************************************\n");
+                warn("!!!! Checkpoint is missing the following version tags:\n");
+                err = true;
+            }
+            warn("  %s\n", t);
+        }
+    }
+    if (err) {
+        warn("You might experience some issues when restoring and should run "
+             "the checkpoint upgrader (util/cpt_upgrader.py) on your "
+             "checkpoint\n");
+        warn("**********************************************************\n");
+    }
+
+    err = false;
+    for (const auto& t : cpt_tags) {
+        if (version_tags.find(t) == version_tags.end()) {
+            // gem5 binary is missing tag that this checkpoint has
+            if (!err) {
+                warn("*****************************************************\n");
+                warn("!!!! gem5 is missing the following version tags:\n");
+                err = true;
+            }
+            warn("  %s\n", t);
+        }
+    }
+    if (err) {
+        warn("Running a checkpoint with incompatible version tags is not "
+             "supported. While it might work, you may experience incorrect "
+             "behavior or crashes.\n");
+        warn("**********************************************************\n");
+     }
 }
 
 Serializable::Serializable()