Added sat -set-init-zero support

diff --git a/passes/sat/sat.cc b/passes/sat/sat.cc
index f77897b068f9d41e84a93d9f97822b817041aef2..cfa97a345349af78d94f9869d074e33db21f95ab 100644 (file)
--- a/passes/sat/sat.cc
+++ b/passes/sat/sat.cc
@@ -50,7 +50,7 @@ struct SatHelper
        bool prove_asserts;
 
        // undef constraints
-       bool enable_undef, set_init_undef, ignore_unknown_cells;
+       bool enable_undef, set_init_undef, set_init_zero, ignore_unknown_cells;
        std::vector<std::string> sets_def, sets_any_undef, sets_all_undef;
        std::map<int, std::vector<std::string>> sets_def_at, sets_any_undef_at, sets_all_undef_at;
 
@@ -67,6 +67,7 @@ struct SatHelper
                this->enable_undef = enable_undef;
                satgen.model_undef = enable_undef;
                set_init_undef = false;
+               set_init_zero = false;
                ignore_unknown_cells = false;
                max_timestep = -1;
                timeout = 0;
@@ -139,6 +140,13 @@ struct SatHelper
                        big_rhs.append(RTLIL::SigSpec(RTLIL::State::Sx, rem.width));
                }
 
+               if (set_init_zero) {
+                       RTLIL::SigSpec rem = satgen.initial_state.export_all();
+                       rem.remove(big_lhs);
+                       big_lhs.append(rem);
+                       big_rhs.append(RTLIL::SigSpec(RTLIL::State::S0, rem.width));
+               }
+
                if (big_lhs.width == 0) {
                        log("No constraints for initial state found.\n\n");
                        return;
@@ -749,6 +757,9 @@ struct SatPass : public Pass {
                log("    -set-init-undef\n");
                log("        set all initial states (not set using -set-init) to undef\n");
                log("\n");
+               log("    -set-init-zero\n");
+               log("        set all initial states (not set using -set-init) to zero\n");
+               log("\n");
                log("The following additional options can be used to set up a proof. If also -seq\n");
                log("is passed, a temporal induction proof is performed.\n");
                log("\n");
@@ -794,7 +805,7 @@ struct SatPass : public Pass {
                std::vector<std::string> shows, sets_def, sets_any_undef, sets_all_undef;
                int loopcount = 0, seq_len = 0, maxsteps = 0, timeout = 0;
                bool verify = false, fail_on_timeout = false, enable_undef = false, set_def_inputs = false;
-               bool ignore_div_by_zero = false, set_init_undef = false, max_undef = false;
+               bool ignore_div_by_zero = false, set_init_undef = false, set_init_zero = false, max_undef = false;
                bool tempinduct = false, prove_asserts = false, show_inputs = false, show_outputs = false;
                bool ignore_unknown_cells = false, falsify = false;
 
@@ -941,6 +952,10 @@ struct SatPass : public Pass {
                                enable_undef = true;
                                continue;
                        }
+                       if (args[argidx] == "-set-init-zero") {
+                               set_init_zero = true;
+                               continue;
+                       }
                        if (args[argidx] == "-show" && argidx+1 < args.size()) {
                                shows.push_back(args[++argidx]);
                                continue;
@@ -975,6 +990,9 @@ struct SatPass : public Pass {
                if (!prove.size() && !prove_x.size() && !prove_asserts && tempinduct)
                        log_cmd_error("Got -tempinduct but nothing to prove!\n");
 
+               if (set_init_undef && set_init_zero)
+                       log_cmd_error("Got -set-init-undef and -set-init-zero!\n");
+
                if (set_def_inputs) {
                        for (auto &it : module->wires)
                                if (it.second->port_input)
@@ -1017,6 +1035,7 @@ struct SatPass : public Pass {
                        basecase.sets_all_undef_at = sets_all_undef_at;
                        basecase.sets_init = sets_init;
                        basecase.set_init_undef = set_init_undef;
+                       basecase.set_init_zero = set_init_zero;
                        basecase.satgen.ignore_div_by_zero = ignore_div_by_zero;
                        basecase.ignore_unknown_cells = ignore_unknown_cells;
 
@@ -1133,6 +1152,7 @@ struct SatPass : public Pass {
                        sathelper.sets_all_undef_at = sets_all_undef_at;
                        sathelper.sets_init = sets_init;
                        sathelper.set_init_undef = set_init_undef;
+                       sathelper.set_init_zero = set_init_zero;
                        sathelper.satgen.ignore_div_by_zero = ignore_div_by_zero;
                        sathelper.ignore_unknown_cells = ignore_unknown_cells;