m68k: only extend the dest reg to tosize during reg-reg moves. this removes a large amount of unnecessary sign and zero extensions from the generated code. this was attempted before, but thanks to other fixes it no longer causes testsuite regressions

git-svn-id: trunk@33648 -

compiler/m68k/cgcpu.pas

@@ -822,7 +822,7 @@ unit cgcpu;
                 add_move_instruction(instr);
                 list.concat(instr);
               end;
-            sign_extend(list,fromsize,reg2);
+            sign_extend(list,fromsize,tosize,reg2);
           end;
       end;