disabled problematic mux -> and/or transform

diff --git a/passes/opt/opt_const.cc b/passes/opt/opt_const.cc
index 2eaba15ce75aaf8c00827f6323ecbce16881872c..5d557b985770649a3bf946230683a7d91a9262d8 100644 (file)
--- a/passes/opt/opt_const.cc
+++ b/passes/opt/opt_const.cc
@@ -681,13 +681,17 @@ void replace_const_cells(RTLIL::Design *design, RTLIL::Module *module, bool cons
                        goto next_cell;
                }
 
+       #if 0
+               // disabled because replacing muxes with and/or gates sometimes causes probems with
+               // simulating undefs (e.g. lm32 from yosys-bigsim vs. icarus verilog init problems)
+
                if (consume_x && mux_bool && (cell->type == "$mux" || cell->type == "$_MUX_") && cell->getPort("\\A") == RTLIL::SigSpec(0, 1)) {
                        cover_list("opt.opt_const.mux_and", "$mux", "$_MUX_", cell->type.str());
                        log("Replacing %s cell `%s' in module `%s' with and-gate.\n", log_id(cell->type), log_id(cell), log_id(module));
                        cell->setPort("\\A", cell->getPort("\\S"));
                        cell->unsetPort("\\S");
                        if (cell->type == "$mux") {
-                               auto width = cell->parameters["\\WIDTH"];
+                               Const width = cell->parameters["\\WIDTH"];
                                cell->parameters["\\A_WIDTH"] = width;
                                cell->parameters["\\B_WIDTH"] = width;
                                cell->parameters["\\Y_WIDTH"] = width;
@@ -707,7 +711,7 @@ void replace_const_cells(RTLIL::Design *design, RTLIL::Module *module, bool cons
                        cell->setPort("\\B", cell->getPort("\\S"));
                        cell->unsetPort("\\S");
                        if (cell->type == "$mux") {
-                               auto width = cell->parameters["\\WIDTH"];
+                               Const width = cell->parameters["\\WIDTH"];
                                cell->parameters["\\A_WIDTH"] = width;
                                cell->parameters["\\B_WIDTH"] = width;
                                cell->parameters["\\Y_WIDTH"] = width;
@@ -720,6 +724,7 @@ void replace_const_cells(RTLIL::Design *design, RTLIL::Module *module, bool cons
                        did_something = true;
                        goto next_cell;
                }
+       #endif
 
                if (mux_undef && (cell->type == "$mux" || cell->type == "$pmux")) {
                        RTLIL::SigSpec new_a, new_b, new_s;