added one more suggestion to optimize MUXes in pass "opt_const"

diff --git a/passes/opt/opt_const.cc b/passes/opt/opt_const.cc
index 909500967cf4bd089de4afd4b9a899b9c04ccb28..5b87aeaa2fb45ed1d384261271acf47eddffd5c6 100644 (file)
--- a/passes/opt/opt_const.cc
+++ b/passes/opt/opt_const.cc
@@ -125,6 +125,7 @@ void replace_const_cells(RTLIL::Design *design, RTLIL::Module *module)
                        if (input.match("  1")) ACTION_DO("\\Y", input.extract(1, 1));
 #ifdef MUX_UNDEF_SEL_TO_UNDEF_RESULTS
                        if (input.match("01 ")) ACTION_DO("\\Y", input.extract(0, 1));
+                       // TODO: "10 " -> replace with "!S" gate
                        // TODO: "0  " -> replace with "B AND S" gate
                        // TODO: " 1 " -> replace with "A OR S" gate
                        // TODO: "1  " -> replace with "B OR !S" gate