diff options
Diffstat (limited to 'passes/fsm/fsm_detect.cc')
| -rw-r--r-- | passes/fsm/fsm_detect.cc | 54 |
1 files changed, 33 insertions, 21 deletions
diff --git a/passes/fsm/fsm_detect.cc b/passes/fsm/fsm_detect.cc index 9fb5446e7..a1c8067b4 100644 --- a/passes/fsm/fsm_detect.cc +++ b/passes/fsm/fsm_detect.cc @@ -34,13 +34,20 @@ static SigSet<sig2driver_entry_t> sig2driver, sig2user; static std::set<RTLIL::Cell*> muxtree_cells; static SigPool sig_at_port; -static bool check_state_mux_tree(RTLIL::SigSpec old_sig, RTLIL::SigSpec sig, pool<Cell*> &recursion_monitor) +static bool check_state_mux_tree(RTLIL::SigSpec old_sig, RTLIL::SigSpec sig, pool<Cell*> &recursion_monitor, dict<RTLIL::SigSpec, bool> &mux_tree_cache) { + if (mux_tree_cache.find(sig) != mux_tree_cache.end()) + return mux_tree_cache.at(sig); + if (sig.is_fully_const() || old_sig == sig) { +ret_true: + mux_tree_cache[sig] = true; return true; } if (sig_at_port.check_any(assign_map(sig))) { +ret_false: + mux_tree_cache[sig] = false; return false; } @@ -49,13 +56,13 @@ static bool check_state_mux_tree(RTLIL::SigSpec old_sig, RTLIL::SigSpec sig, poo for (auto &cellport : cellport_list) { if ((cellport.first->type != "$mux" && cellport.first->type != "$pmux") || cellport.second != "\\Y") { - return false; + goto ret_false; } if (recursion_monitor.count(cellport.first)) { log_warning("logic loop in mux tree at signal %s in module %s.\n", log_signal(sig), RTLIL::id2cstr(module->name)); - return false; + goto ret_false; } recursion_monitor.insert(cellport.first); @@ -63,22 +70,22 @@ static bool check_state_mux_tree(RTLIL::SigSpec old_sig, RTLIL::SigSpec sig, poo RTLIL::SigSpec sig_a = assign_map(cellport.first->getPort("\\A")); RTLIL::SigSpec sig_b = assign_map(cellport.first->getPort("\\B")); - if (!check_state_mux_tree(old_sig, sig_a, recursion_monitor)) { + if (!check_state_mux_tree(old_sig, sig_a, recursion_monitor, mux_tree_cache)) { recursion_monitor.erase(cellport.first); - return false; + goto ret_false; } for (int i = 0; i < sig_b.size(); i += sig_a.size()) - if (!check_state_mux_tree(old_sig, sig_b.extract(i, sig_a.size()), recursion_monitor)) { + if (!check_state_mux_tree(old_sig, sig_b.extract(i, sig_a.size()), recursion_monitor, mux_tree_cache)) { recursion_monitor.erase(cellport.first); - return false; + goto ret_false; } recursion_monitor.erase(cellport.first); muxtree_cells.insert(cellport.first); } - return true; + goto ret_true; } static bool check_state_users(RTLIL::SigSpec sig) @@ -143,11 +150,12 @@ static void detect_fsm(RTLIL::Wire *wire) pool<Cell*> recursion_monitor; RTLIL::SigSpec sig_q = assign_map(cellport.first->getPort("\\Q")); RTLIL::SigSpec sig_d = assign_map(cellport.first->getPort("\\D")); + dict<RTLIL::SigSpec, bool> mux_tree_cache; if (sig_q != assign_map(wire)) continue; - looks_like_state_reg = check_state_mux_tree(sig_q, sig_d, recursion_monitor); + looks_like_state_reg = check_state_mux_tree(sig_q, sig_d, recursion_monitor, mux_tree_cache); looks_like_good_state_reg = check_state_users(sig_q); if (!looks_like_state_reg) @@ -158,22 +166,25 @@ static void detect_fsm(RTLIL::Wire *wire) std::set<sig2driver_entry_t> cellport_list; sig2user.find(sig_q, cellport_list); + auto sig_q_bits = sig_q.to_sigbit_pool(); + for (auto &cellport : cellport_list) { RTLIL::Cell *cell = cellport.first; bool set_output = false, clr_output = false; - if (cell->type == "$ne") + if (cell->type.in("$ne", "$reduce_or", "$reduce_bool")) set_output = true; - if (cell->type == "$eq") + if (cell->type.in("$eq", "$logic_not", "$reduce_and")) clr_output = true; - if (!set_output && !clr_output) { - clr_output = true; + if (set_output || clr_output) { for (auto &port_it : cell->connections()) - if (port_it.first != "\\A" || port_it.first != "\\Y") - clr_output = false; + if (cell->input(port_it.first)) + for (auto bit : assign_map(port_it.second)) + if (bit.wire != nullptr && !sig_q_bits.count(bit)) + goto next_cellport; } if (set_output || clr_output) { @@ -184,6 +195,7 @@ static void detect_fsm(RTLIL::Wire *wire) ce.set(sig, val); } } + next_cellport:; } SigSpec sig_y = sig_d, sig_undef; @@ -196,13 +208,13 @@ static void detect_fsm(RTLIL::Wire *wire) vector<string> warnings; if (is_module_port) - warnings.push_back("Forcing fsm recoding on module port might result in larger circuit.\n"); + warnings.push_back("Forcing FSM recoding on module port might result in larger circuit.\n"); if (!looks_like_good_state_reg) - warnings.push_back("Users of state reg look like fsm recoding might result in larger circuit.\n"); + warnings.push_back("Users of state reg look like FSM recoding might result in larger circuit.\n"); if (has_init_attr) - warnings.push_back("Init value on fsm state registers are ignored. Possible simulation-synthesis mismatch!"); + warnings.push_back("Initialization value on FSM state register is ignored. Possible simulation-synthesis mismatch!\n"); if (!looks_like_state_reg) warnings.push_back("Doesn't look like a proper FSM. Possible simulation-synthesis mismatch!\n"); @@ -236,7 +248,7 @@ static void detect_fsm(RTLIL::Wire *wire) log(" Users of register don't seem to benefit from recoding.\n"); if (has_init_attr) - log(" Register has an initialization value."); + log(" Register has an initialization value.\n"); if (is_self_resetting) log(" Circuit seems to be self-resetting.\n"); @@ -245,7 +257,7 @@ static void detect_fsm(RTLIL::Wire *wire) struct FsmDetectPass : public Pass { FsmDetectPass() : Pass("fsm_detect", "finding FSMs in design") { } - virtual void help() + void help() YS_OVERRIDE { // |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---| log("\n"); @@ -261,7 +273,7 @@ struct FsmDetectPass : public Pass { log("'fsm_encoding' attribute to \"none\".\n"); log("\n"); } - virtual void execute(std::vector<std::string> args, RTLIL::Design *design) + void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE { log_header(design, "Executing FSM_DETECT pass (finding FSMs in design).\n"); extra_args(args, 1, design); |