insert CSE after constant propagation and before CSE2

=> useful to have a nice generated code for || (and also probably &&)

tools/compiler_expand.ml

@@ -32,6 +32,7 @@ PARTIAL, Always, NoRequire, (Some "Unrolling the body of innermost loops"), "Unr
 TOTAL, Always, NoRequire, (Some "Renumbering pre constprop"), "Renumber";
 TOTAL, (Option "optim_constprop"), Require, (Some "Constant propagation"), "Constprop";
 TOTAL, Always, NoRequire, (Some "Renumbering pre CSE"), "Renumber";
+PARTIAL, (Option "optim_CSE"), Require, (Some "CSE"), "CSE";
 TOTAL, (Option "optim_CSE2"), Require, (Some "CSE2"), "CSE2";
 PARTIAL, (Option "optim_CSE3"), Require, (Some "CSE3"), "CSE3";
 TOTAL, (Option "optim_CSE3"), Require, (Some "Kill useless moves after CSE3"), "KillUselessMoves";