Cleanup abc9, update doc for -keepff option

diff --git a/passes/techmap/abc9.cc b/passes/techmap/abc9.cc
index a02b8d73b286385a529ea5b0b3b17c2b4a372db3..c3c8e0dbc1ce89f89c71d727a7af7dd95d56b238 100644 (file)
--- a/passes/techmap/abc9.cc
+++ b/passes/techmap/abc9.cc
@@ -250,7 +250,7 @@ struct abc9_output_filter
 
 void abc9_module(RTLIL::Design *design, RTLIL::Module *module, std::string script_file, std::string exe_file,
                bool cleanup, vector<int> lut_costs, bool keepff, std::string delay_target, std::string /*lutin_shared*/, bool fast_mode,
-               const std::vector<RTLIL::Cell*> &/*cells*/, bool show_tempdir, std::string box_file, std::string lut_file,
+               bool show_tempdir, std::string box_file, std::string lut_file,
                std::string wire_delay, bool nomfs
 )
 {
@@ -796,8 +796,8 @@ struct Abc9Pass : public Pass {
                log("        2, 3, .. inputs.\n");
                log("\n");
                log("    -keepff\n");
-               log("        set the \"keep\" attribute on flip-flop output wires. (and thus preserve\n");
-               log("        them, for example for equivalence checking.)\n");
+               log("        do not represent (* abc9_flop *) modules as boxes (and thus do not perform\n");
+               log("        any form of sequential synthesis).\n");
                log("\n");
                log("    -nocleanup\n");
                log("        when this option is used, the temporary files created by this pass\n");
@@ -985,10 +985,9 @@ struct Abc9Pass : public Pass {
                        typedef SigSpec clkdomain_t;
                        dict<clkdomain_t, int> clk_to_mergeability;
 
-                       const std::vector<RTLIL::Cell*> all_cells = module->selected_cells();
 
                        if (!keepff)
-                               for (auto cell : all_cells) {
+                               for (auto cell : module->selected_cells()) {
                                        auto inst_module = design->module(cell->type);
                                        if (!inst_module || !inst_module->get_bool_attribute("\\abc9_flop"))
                                                continue;
@@ -1017,7 +1016,7 @@ struct Abc9Pass : public Pass {
 
                        design->selected_active_module = module->name.str();
                        abc9_module(design, module, script_file, exe_file, cleanup, lut_costs, keepff,
-                                       delay_target, lutin_shared, fast_mode, all_cells, show_tempdir,
+                                       delay_target, lutin_shared, fast_mode, show_tempdir,
                                        box_file, lut_file, wire_delay, nomfs);
                        design->selected_active_module.clear();
                }