2 files changed, 64 insertions, 1 deletions

diff --git a/src/sim/process.cc b/src/sim/process.cc
index a01cfea91..db013aee0 100644
--- a/src/sim/process.cc
+++ b/src/sim/process.cc
@@ -75,6 +75,37 @@
 using namespace std;
 using namespace TheISA;
 
+namespace
+{
+
+typedef std::vector<Process::Loader *> LoaderList;
+
+LoaderList &
+process_loaders()
+{
+    static LoaderList loaders;
+    return loaders;
+}
+
+} // anonymous namespace
+
+Process::Loader::Loader()
+{
+    process_loaders().emplace_back(this);
+}
+
+Process *
+Process::tryLoaders(ProcessParams *params, ObjectFile *obj_file)
+{
+    for (auto &loader: process_loaders()) {
+        Process *p = loader->load(params, obj_file);
+        if (p)
+            return p;
+    }
+
+    return nullptr;
+}
+
 static std::string
 normalize(std::string& directory)
 {
@@ -554,7 +585,7 @@ ProcessParams::create()
     ObjectFile *obj_file = createObjectFile(executable);
     fatal_if(!obj_file, "Cannot load object file %s.", executable);
 
-    Process *process = ObjectFile::tryLoaders(this, obj_file);
+    Process *process = Process::tryLoaders(this, obj_file);
     fatal_if(!process, "Unknown error creating process object.");
 
     return process;
diff --git a/src/sim/process.hh b/src/sim/process.hh
index 8e353071c..a28d58e9a 100644
--- a/src/sim/process.hh
+++ b/src/sim/process.hh
@@ -183,6 +183,38 @@ class Process : public SimObject
 
     SETranslatingPortProxy initVirtMem; // memory proxy for initial image load
 
+    /**
+     * Each instance of a Loader subclass will have a chance to try to load
+     * an object file when tryLoaders is called. If they can't because they
+     * aren't compatible with it (wrong arch, wrong OS, etc), then they
+     * silently fail by returning nullptr so other loaders can try.
+     */
+    class Loader
+    {
+      public:
+        Loader();
+
+        /* Loader instances are singletons. */
+        Loader(const Loader &) = delete;
+        void operator=(const Loader &) = delete;
+
+        virtual ~Loader() {}
+
+        /**
+         * Each subclass needs to implement this method. If the loader is
+         * compatible with the passed in object file, it should return the
+         * created Process object corresponding to it. If not, it should fail
+         * silently and return nullptr. If there's a non-compatibliity related
+         * error like file IO errors, etc., those should fail non-silently
+         * with a panic or fail as normal.
+         */
+        virtual Process *load(ProcessParams *params, ObjectFile *obj_file) = 0;
+    };
+
+    // Try all the Loader instance's "load" methods one by one until one is
+    // successful. If none are, complain and fail.
+    static Process *tryLoaders(ProcessParams *params, ObjectFile *obj_file);
+
     ObjectFile *objFile;
     MemoryImage image;
     MemoryImage interpImage;