Added approach description

plan.txt

@@ -0,0 +1,9 @@
+General:
+- Use custom __builtin_offsetof definition to preserve the call until lower gimple
+
+Approach:
+- At the very last point of gimple (after gimple optimizations), recognize accesses
+	- Build a mapping of statement location (multiple statements share) to a semantic graph (or tree)
+- Right after expansion to RTL, pattern match set of RTL instructions with same location to graph
+	- Add notes (persistent over RTL transformations) to any RTL instruction that is relevant
+- After all RTL optimizations, add assembly labels before relevant RTL instructions (identified by notes)

plugin/main.cpp

@@ -349,8 +349,8 @@ int plugin_init(plugin_name_args *plugin_info, plugin_gcc_version *version)
 
     struct register_pass_info ginfo;
     ginfo.pass = new gimplabels_pass(nullptr);
-    ginfo.reference_pass_name = "cfg";
     ginfo.ref_pass_instance_number = 1;
+    ginfo.reference_pass_name = "optimized";
     ginfo.pos_op = PASS_POS_INSERT_AFTER;
     register_callback(plugin_info->base_name, PLUGIN_PASS_MANAGER_SETUP, nullptr, &ginfo);