diff --git a/MiniC/TP04/AllInMemAllocator.py b/MiniC/TP04/AllInMemAllocator.py
index 7e73a27..7b08b30 100644
--- a/MiniC/TP04/AllInMemAllocator.py
+++ b/MiniC/TP04/AllInMemAllocator.py
@@ -18,15 +18,15 @@ class AllInMemAllocator(Allocator):
         s_index = 0
         for arg in old_instr.args():
             if isinstance(arg, Temporary):
-                # TODO: don't ld/sd when nothing changed (eg don't ld a destination only,
-                # TODO: don't sd a source only)
                 s_index += 1
-                before.append(RiscV.ld(
-                    S[s_index], arg.get_alloced_loc()
-                ))
-                after.append(RiscV.sd(
-                    S[s_index], arg.get_alloced_loc()
-                ))
+                if arg in old_instr.used(): # needs to be read first
+                    before.append(RiscV.ld(
+                        S[s_index], arg.get_alloced_loc()
+                    ))
+                if arg in old_instr.defined(): # needs to be stored after
+                    after.append(RiscV.sd(
+                        S[s_index], arg.get_alloced_loc()
+                    ))
                 new_args.append(S[s_index])
             else:
                 new_args.append(arg)