More bugfixes related to new RTLIL::IdString

[yosys.git] / passes / cmds / select.cc

/*
 *  yosys -- Yosys Open SYnthesis Suite
 *
 *  Copyright (C) 2012  Clifford Wolf <clifford@clifford.at>
 *  
 *  Permission to use, copy, modify, and/or distribute this software for any
 *  purpose with or without fee is hereby granted, provided that the above
 *  copyright notice and this permission notice appear in all copies.
 *  
 *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */

#include "kernel/register.h"
#include "kernel/celltypes.h"
#include "kernel/sigtools.h"
#include "kernel/log.h"
#include <string.h>
#include <fnmatch.h>
#include <errno.h>

using RTLIL::id2cstr;

static std::vector<RTLIL::Selection> work_stack;

static bool match_ids(RTLIL::IdString id, std::string pattern)
{
        if (id == pattern)
                return true;
        if (id.size() > 0 && id[0] == '\\' && id.substr(1) == pattern)
                return true;
        if (!fnmatch(pattern.c_str(), id.c_str(), 0))
                return true;
        if (id.size() > 0 && id[0] == '\\' && !fnmatch(pattern.c_str(), id.substr(1).c_str(), 0))
                return true;
        if (id.size() > 0 && id[0] == '$' && pattern.size() > 0 && pattern[0] == '$') {
                const char *p = id.c_str();
                const char *q = strrchr(p, '$');
                if (pattern == q)
                        return true;
        }
        return false;
}

static bool match_attr_val(const RTLIL::Const &value, std::string pattern, char match_op)
{
        if (match_op == 0)
                return true;

        if ((value.flags & RTLIL::CONST_FLAG_STRING) == 0)
        {
                RTLIL::SigSpec sig_value;

                if (!RTLIL::SigSpec::parse(sig_value, NULL, pattern))
                        return false;

                RTLIL::Const pattern_value = sig_value.as_const();

                if (match_op == '=')
                        return value == pattern_value;
                if (match_op == '!')
                        return value != pattern_value;
                if (match_op == '<')
                        return value.as_int() < pattern_value.as_int();
                if (match_op == '>')
                        return value.as_int() > pattern_value.as_int();
                if (match_op == '[')
                        return value.as_int() <= pattern_value.as_int();
                if (match_op == ']')
                        return value.as_int() >= pattern_value.as_int();
        }
        else
        {
                std::string value_str = value.decode_string();

                if (match_op == '=')
                        if (!fnmatch(pattern.c_str(), value.decode_string().c_str(), FNM_NOESCAPE))
                                return true;

                if (match_op == '=')
                        return value_str == pattern;
                if (match_op == '!')
                        return value_str != pattern;
                if (match_op == '<')
                        return value_str < pattern;
                if (match_op == '>')
                        return value_str > pattern;
                if (match_op == '[')
                        return value_str <= pattern;
                if (match_op == ']')
                        return value_str >= pattern;
        }

        log_abort();
}

static bool match_attr(const std::map<RTLIL::IdString, RTLIL::Const> &attributes, std::string name_pat, std::string value_pat, char match_op)
{
        if (name_pat.find('*') != std::string::npos || name_pat.find('?') != std::string::npos || name_pat.find('[') != std::string::npos) {
                for (auto &it : attributes) {
                        if (!fnmatch(name_pat.c_str(), it.first.c_str(), FNM_NOESCAPE) && match_attr_val(it.second, value_pat, match_op))
                                return true;
                        if (it.first.size() > 0 && it.first[0] == '\\' && !fnmatch(name_pat.c_str(), it.first.substr(1).c_str(), FNM_NOESCAPE) && match_attr_val(it.second, value_pat, match_op))
                                return true;
                }
        } else {
                if (name_pat.size() > 0 && (name_pat[0] == '\\' || name_pat[0] == '$') && attributes.count(name_pat) && match_attr_val(attributes.at(name_pat), value_pat, match_op))
                        return true;
                if (attributes.count("\\" + name_pat) && match_attr_val(attributes.at("\\" + name_pat), value_pat, match_op))
                        return true;
        }
        return false;
}

static bool match_attr(const std::map<RTLIL::IdString, RTLIL::Const> &attributes, std::string match_expr)
{
        size_t pos = match_expr.find_first_of("<!=>");

        if (pos != std::string::npos) {
                if (match_expr.substr(pos, 2) == "!=")
                        return match_attr(attributes, match_expr.substr(0, pos), match_expr.substr(pos+2), '!');
                if (match_expr.substr(pos, 2) == "<=")
                        return match_attr(attributes, match_expr.substr(0, pos), match_expr.substr(pos+2), '[');
                if (match_expr.substr(pos, 2) == ">=")
                        return match_attr(attributes, match_expr.substr(0, pos), match_expr.substr(pos+2), ']');
                return match_attr(attributes, match_expr.substr(0, pos), match_expr.substr(pos+1), match_expr[pos]);
        }

        return match_attr(attributes, match_expr, std::string(), 0);
}

static void select_op_neg(RTLIL::Design *design, RTLIL::Selection &lhs)
{
        if (lhs.full_selection) {
                lhs.full_selection = false;
                lhs.selected_modules.clear();
                lhs.selected_members.clear();
                return;
        }

        if (lhs.selected_modules.size() == 0 && lhs.selected_members.size() == 0) {
                lhs.full_selection = true;
                return;
        }

        RTLIL::Selection new_sel(false);

        for (auto &mod_it : design->modules_)
        {
                if (lhs.selected_whole_module(mod_it.first))
                        continue;
                if (!lhs.selected_module(mod_it.first)) {
                        new_sel.selected_modules.insert(mod_it.first);
                        continue;
                }

                RTLIL::Module *mod = mod_it.second;
                for (auto &it : mod->wires_)
                        if (!lhs.selected_member(mod_it.first, it.first))
                                new_sel.selected_members[mod->name].insert(it.first);
                for (auto &it : mod->memories)
                        if (!lhs.selected_member(mod_it.first, it.first))
                                new_sel.selected_members[mod->name].insert(it.first);
                for (auto &it : mod->cells_)
                        if (!lhs.selected_member(mod_it.first, it.first))
                                new_sel.selected_members[mod->name].insert(it.first);
                for (auto &it : mod->processes)
                        if (!lhs.selected_member(mod_it.first, it.first))
                                new_sel.selected_members[mod->name].insert(it.first);
        }

        lhs.selected_modules.swap(new_sel.selected_modules);
        lhs.selected_members.swap(new_sel.selected_members);
}

static void select_op_submod(RTLIL::Design *design, RTLIL::Selection &lhs)
{
        for (auto &mod_it : design->modules_)
        {
                if (lhs.selected_whole_module(mod_it.first))
                {
                        for (auto &cell_it : mod_it.second->cells_)
                        {
                                if (design->modules_.count(cell_it.second->type) == 0)
                                        continue;
                                lhs.selected_modules.insert(cell_it.second->type);
                        }
                }
        }
}

static void select_op_fullmod(RTLIL::Design *design, RTLIL::Selection &lhs)
{
        lhs.optimize(design);
        for (auto &it : lhs.selected_members)
                lhs.selected_modules.insert(it.first);
        lhs.selected_members.clear();
}

static void select_op_alias(RTLIL::Design *design, RTLIL::Selection &lhs)
{
        for (auto &mod_it : design->modules_)
        {
                if (lhs.selected_whole_module(mod_it.first))
                        continue;
                if (!lhs.selected_module(mod_it.first))
                        continue;

                SigMap sigmap(mod_it.second);
                SigPool selected_bits;

                for (auto &it : mod_it.second->wires_)
                        if (lhs.selected_member(mod_it.first, it.first))
                                selected_bits.add(sigmap(it.second));

                for (auto &it : mod_it.second->wires_)
                        if (!lhs.selected_member(mod_it.first, it.first) && selected_bits.check_any(sigmap(it.second)))
                                lhs.selected_members[mod_it.first].insert(it.first);
        }
}

static void select_op_union(RTLIL::Design*, RTLIL::Selection &lhs, const RTLIL::Selection &rhs)
{
        if (rhs.full_selection) {
                lhs.full_selection = true;
                lhs.selected_modules.clear();
                lhs.selected_members.clear();
                return;
        }

        if (lhs.full_selection)
                return;

        for (auto &it : rhs.selected_members)
                for (auto &it2 : it.second)
                        lhs.selected_members[it.first].insert(it2);

        for (auto &it : rhs.selected_modules) {
                lhs.selected_modules.insert(it);
                lhs.selected_members.erase(it);
        }
}

static void select_op_diff(RTLIL::Design *design, RTLIL::Selection &lhs, const RTLIL::Selection &rhs)
{
        if (rhs.full_selection) {
                lhs.full_selection = false;
                lhs.selected_modules.clear();
                lhs.selected_members.clear();
                return;
        }

        if (lhs.full_selection) {
                if (!rhs.full_selection && rhs.selected_modules.size() == 0 && rhs.selected_members.size() == 0)
                        return;
                lhs.full_selection = false;
                for (auto &it : design->modules_)
                        lhs.selected_modules.insert(it.first);
        }

        for (auto &it : rhs.selected_modules) {
                lhs.selected_modules.erase(it);
                lhs.selected_members.erase(it);
        }

        for (auto &it : rhs.selected_members)
        {
                if (design->modules_.count(it.first) == 0)
                        continue;

                RTLIL::Module *mod = design->modules_[it.first];

                if (lhs.selected_modules.count(mod->name) > 0)
                {
                        for (auto &it : mod->wires_)
                                lhs.selected_members[mod->name].insert(it.first);
                        for (auto &it : mod->memories)
                                lhs.selected_members[mod->name].insert(it.first);
                        for (auto &it : mod->cells_)
                                lhs.selected_members[mod->name].insert(it.first);
                        for (auto &it : mod->processes)
                                lhs.selected_members[mod->name].insert(it.first);
                        lhs.selected_modules.erase(mod->name);
                }

                if (lhs.selected_members.count(mod->name) == 0)
                        continue;

                for (auto &it2 : it.second)
                        lhs.selected_members[mod->name].erase(it2);
        }
}

static void select_op_intersect(RTLIL::Design *design, RTLIL::Selection &lhs, const RTLIL::Selection &rhs)
{
        if (rhs.full_selection)
                return;

        if (lhs.full_selection) {
                lhs.full_selection = false;
                for (auto &it : design->modules_)
                        lhs.selected_modules.insert(it.first);
        }

        std::vector<RTLIL::IdString> del_list;

        for (auto &it : lhs.selected_modules)
                if (rhs.selected_modules.count(it) == 0) {
                        if (rhs.selected_members.count(it) > 0)
                                for (auto &it2 : rhs.selected_members.at(it))
                                        lhs.selected_members[it].insert(it2);
                        del_list.push_back(it);
                }
        for (auto &it : del_list)
                lhs.selected_modules.erase(it);

        del_list.clear();
        for (auto &it : lhs.selected_members) {
                if (rhs.selected_modules.count(it.first) > 0)
                        continue;
                if (rhs.selected_members.count(it.first) == 0) {
                        del_list.push_back(it.first);
                        continue;
                }
                std::vector<RTLIL::IdString> del_list2;
                for (auto &it2 : it.second)
                        if (rhs.selected_members.at(it.first).count(it2) == 0)
                                del_list2.push_back(it2);
                for (auto &it2 : del_list2)
                        it.second.erase(it2);
                if (it.second.size() == 0)
                        del_list.push_back(it.first);
        }
        for (auto &it : del_list)
                lhs.selected_members.erase(it);
}

namespace {
        struct expand_rule_t {
                char mode;
                std::set<RTLIL::IdString> cell_types, port_names;
        };
}

static int parse_comma_list(std::set<RTLIL::IdString> &tokens, std::string str, size_t pos, std::string stopchar)
{
        stopchar += ',';
        while (1) {
                size_t endpos = str.find_first_of(stopchar, pos);
                if (endpos == std::string::npos)
                        endpos = str.size();
                if (endpos != pos)
                        tokens.insert(RTLIL::escape_id(str.substr(pos, endpos-pos)));
                pos = endpos;
                if (pos == str.size() || str[pos] != ',')
                        return pos;
                pos++;
        }
}

static int select_op_expand(RTLIL::Design *design, RTLIL::Selection &lhs, std::vector<expand_rule_t> &rules, std::set<RTLIL::IdString> &limits, int max_objects, char mode, CellTypes &ct)
{
        int sel_objects = 0;
        bool is_input, is_output;
        for (auto &mod_it : design->modules_)
        {
                if (lhs.selected_whole_module(mod_it.first) || !lhs.selected_module(mod_it.first))
                        continue;

                RTLIL::Module *mod = mod_it.second;
                std::set<RTLIL::Wire*> selected_wires;

                for (auto &it : mod->wires_)
                        if (lhs.selected_member(mod_it.first, it.first) && limits.count(it.first) == 0)
                                selected_wires.insert(it.second);

                for (auto &conn : mod->connections())
                {
                        std::vector<RTLIL::SigBit> conn_lhs = conn.first.to_sigbit_vector();
                        std::vector<RTLIL::SigBit> conn_rhs = conn.second.to_sigbit_vector();

                        for (size_t i = 0; i < conn_lhs.size(); i++) {
                                if (conn_lhs[i].wire == NULL || conn_rhs[i].wire == NULL)
                                        continue;
                                if (mode != 'i' && selected_wires.count(conn_rhs[i].wire) && lhs.selected_members[mod->name].count(conn_lhs[i].wire->name) == 0)
                                        lhs.selected_members[mod->name].insert(conn_lhs[i].wire->name), sel_objects++, max_objects--;
                                if (mode != 'o' && selected_wires.count(conn_lhs[i].wire) && lhs.selected_members[mod->name].count(conn_rhs[i].wire->name) == 0)
                                        lhs.selected_members[mod->name].insert(conn_rhs[i].wire->name), sel_objects++, max_objects--;
                        }
                }

                for (auto &cell : mod->cells_)
                for (auto &conn : cell.second->connections())
                {
                        char last_mode = '-';
                        for (auto &rule : rules) {
                                last_mode = rule.mode;
                                if (rule.cell_types.size() > 0 && rule.cell_types.count(cell.second->type) == 0)
                                        continue;
                                if (rule.port_names.size() > 0 && rule.port_names.count(conn.first) == 0)
                                        continue;
                                if (rule.mode == '+')
                                        goto include_match;
                                else
                                        goto exclude_match;
                        }
                        if (last_mode == '+')
                                goto exclude_match;
                include_match:
                        is_input = mode == 'x' || ct.cell_input(cell.second->type, conn.first);
                        is_output = mode == 'x' || ct.cell_output(cell.second->type, conn.first);
                        for (auto &chunk : conn.second.chunks())
                                if (chunk.wire != NULL) {
                                        if (max_objects != 0 && selected_wires.count(chunk.wire) > 0 && lhs.selected_members[mod->name].count(cell.first) == 0)
                                                if (mode == 'x' || (mode == 'i' && is_output) || (mode == 'o' && is_input))
                                                        lhs.selected_members[mod->name].insert(cell.first), sel_objects++, max_objects--;
                                        if (max_objects != 0 && lhs.selected_members[mod->name].count(cell.first) > 0 && limits.count(cell.first) == 0 && lhs.selected_members[mod->name].count(chunk.wire->name) == 0)
                                                if (mode == 'x' || (mode == 'i' && is_input) || (mode == 'o' && is_output))
                                                        lhs.selected_members[mod->name].insert(chunk.wire->name), sel_objects++, max_objects--;
                                }
                exclude_match:;
                }
        }

        return sel_objects;
}

static void select_op_expand(RTLIL::Design *design, std::string arg, char mode)
{
        int pos = mode == 'x' ? 2 : 3, levels = 1, rem_objects = -1;
        std::vector<expand_rule_t> rules;
        std::set<RTLIL::IdString> limits;

        CellTypes ct;

        if (mode != 'x')
                ct.setup(design);

        if (pos < int(arg.size()) && arg[pos] == '*') {
                levels = 1000000;
                pos++;
        } else
        if (pos < int(arg.size()) && '0' <= arg[pos] && arg[pos] <= '9') {
                size_t endpos = arg.find_first_not_of("0123456789", pos);
                if (endpos == std::string::npos)
                        endpos = arg.size();
                levels = atoi(arg.substr(pos, endpos-pos).c_str());
                pos = endpos;
        }

        if (pos < int(arg.size()) && arg[pos] == '.') {
                size_t endpos = arg.find_first_not_of("0123456789", ++pos);
                if (endpos == std::string::npos)
                        endpos = arg.size();
                if (int(endpos) > pos)
                        rem_objects = atoi(arg.substr(pos, endpos-pos).c_str());
                pos = endpos;
        }

        while (pos < int(arg.size())) {
                if (arg[pos] != ':' || pos+1 == int(arg.size()))
                        log_cmd_error("Syntax error in expand operator '%s'.\n", arg.c_str());
                pos++;
                if (arg[pos] == '+' || arg[pos] == '-') {
                        expand_rule_t rule;
                        rule.mode = arg[pos++];
                        pos = parse_comma_list(rule.cell_types, arg, pos, "[:");
                        if (pos < int(arg.size()) && arg[pos] == '[') {
                                pos = parse_comma_list(rule.port_names, arg, pos+1, "]:");
                                if (pos < int(arg.size()) && arg[pos] == ']')
                                        pos++;
                        }
                        rules.push_back(rule);
                } else {
                        size_t endpos = arg.find(':', pos);
                        if (endpos == std::string::npos)
                                endpos = arg.size();
                        if (int(endpos) > pos) {
                                std::string str = arg.substr(pos, endpos-pos);
                                if (str[0] == '@') {
                                        str = RTLIL::escape_id(str.substr(1));
                                        if (design->selection_vars.count(str) > 0) {
                                                for (auto i1 : design->selection_vars.at(str).selected_members)
                                                for (auto i2 : i1.second)
                                                        limits.insert(i2);
                                        } else
                                                log_cmd_error("Selection %s is not defined!\n", RTLIL::unescape_id(str).c_str());
                                } else
                                        limits.insert(RTLIL::escape_id(str));
                        }
                        pos = endpos;
                }
        }

#if 0
        log("expand by %d levels (max. %d objects):\n", levels, rem_objects);
        for (auto &rule : rules) {
                log("  rule (%c):\n", rule.mode);
                if (rule.cell_types.size() > 0) {
                        log("    cell types:");
                        for (auto &it : rule.cell_types)
                                log(" %s", it.c_str());
                        log("\n");
                }
                if (rule.port_names.size() > 0) {
                        log("    port names:");
                        for (auto &it : rule.port_names)
                                log(" %s", it.c_str());
                        log("\n");
                }
        }
        if (limits.size() > 0) {
                log("  limits:");
                for (auto &it : limits)
                        log(" %s", it.c_str());
                log("\n");
        }
#endif

        while (levels-- > 0 && rem_objects != 0) {
                int num_objects = select_op_expand(design, work_stack.back(), rules, limits, rem_objects, mode, ct);
                if (num_objects == 0)
                        break;
                rem_objects -= num_objects;
        }

        if (rem_objects == 0)
                log("Warning: reached configured limit at `%s'.\n", arg.c_str());
}

static void select_filter_active_mod(RTLIL::Design *design, RTLIL::Selection &sel)
{
        if (design->selected_active_module.empty())
                return;
        
        if (sel.full_selection) {
                sel.full_selection = false;
                sel.selected_modules.clear();
                sel.selected_members.clear();
                sel.selected_modules.insert(design->selected_active_module);
                return;
        }

        std::vector<RTLIL::IdString> del_list;
        for (auto mod_name : sel.selected_modules)
                if (mod_name != design->selected_active_module)
                        del_list.push_back(mod_name);
        for (auto &it : sel.selected_members)
                if (it.first != design->selected_active_module)
                        del_list.push_back(it.first);
        for (auto mod_name : del_list) {
                sel.selected_modules.erase(mod_name);
                sel.selected_members.erase(mod_name);
        }
}

static void select_stmt(RTLIL::Design *design, std::string arg)
{
        std::string arg_mod, arg_memb;

        if (arg.size() == 0)
                return;

        if (arg[0] == '%') {
                if (arg == "%") {
                        if (design->selection_stack.size() > 0)
                                work_stack.push_back(design->selection_stack.back());
                } else
                if (arg == "%%") {
                        while (work_stack.size() > 1) {
                                select_op_union(design, work_stack.front(), work_stack.back());
                                work_stack.pop_back();
                        }
                } else
                if (arg == "%n") {
                        if (work_stack.size() < 1)
                                log_cmd_error("Must have at least one element on the stack for operator %%n.\n");
                        select_op_neg(design, work_stack[work_stack.size()-1]);
                } else
                if (arg == "%u") {
                        if (work_stack.size() < 2)
                                log_cmd_error("Must have at least two elements on the stack for operator %%u.\n");
                        select_op_union(design, work_stack[work_stack.size()-2], work_stack[work_stack.size()-1]);
                        work_stack.pop_back();
                } else
                if (arg == "%d") {
                        if (work_stack.size() < 2)
                                log_cmd_error("Must have at least two elements on the stack for operator %%d.\n");
                        select_op_diff(design, work_stack[work_stack.size()-2], work_stack[work_stack.size()-1]);
                        work_stack.pop_back();
                } else
                if (arg == "%D") {
                        if (work_stack.size() < 2)
                                log_cmd_error("Must have at least two elements on the stack for operator %%d.\n");
                        select_op_diff(design, work_stack[work_stack.size()-1], work_stack[work_stack.size()-2]);
                        work_stack[work_stack.size()-2] = work_stack[work_stack.size()-1];
                        work_stack.pop_back();
                } else
                if (arg == "%i") {
                        if (work_stack.size() < 2)
                                log_cmd_error("Must have at least two elements on the stack for operator %%i.\n");
                        select_op_intersect(design, work_stack[work_stack.size()-2], work_stack[work_stack.size()-1]);
                        work_stack.pop_back();
                } else
                if (arg == "%s") {
                        if (work_stack.size() < 1)
                                log_cmd_error("Must have at least one element on the stack for operator %%s.\n");
                        select_op_submod(design, work_stack[work_stack.size()-1]);
                } else
                if (arg == "%c") {
                        if (work_stack.size() < 1)
                                log_cmd_error("Must have at least one element on the stack for operator %%c.\n");
                        work_stack.push_back(work_stack.back());
                } else
                if (arg == "%m") {
                        if (work_stack.size() < 1)
                                log_cmd_error("Must have at least one element on the stack for operator %%m.\n");
                        select_op_fullmod(design, work_stack[work_stack.size()-1]);
                } else
                if (arg == "%a") {
                        if (work_stack.size() < 1)
                                log_cmd_error("Must have at least one element on the stack for operator %%a.\n");
                        select_op_alias(design, work_stack[work_stack.size()-1]);
                } else
                if (arg == "%x" || (arg.size() > 2 && arg.substr(0, 2) == "%x" && (arg[2] == ':' || arg[2] == '*' || arg[2] == '.' || ('0' <= arg[2] && arg[2] <= '9')))) {
                        if (work_stack.size() < 1)
                                log_cmd_error("Must have at least one element on the stack for operator %%x.\n");
                        select_op_expand(design, arg, 'x');
                } else
                if (arg == "%ci" || (arg.size() > 3 && arg.substr(0, 3) == "%ci" && (arg[3] == ':' || arg[3] == '*' || arg[3] == '.' || ('0' <= arg[3] && arg[3] <= '9')))) {
                        if (work_stack.size() < 1)
                                log_cmd_error("Must have at least one element on the stack for operator %%ci.\n");
                        select_op_expand(design, arg, 'i');
                } else
                if (arg == "%co" || (arg.size() > 3 && arg.substr(0, 3) == "%co" && (arg[3] == ':' || arg[3] == '*' || arg[3] == '.' || ('0' <= arg[3] && arg[3] <= '9')))) {
                        if (work_stack.size() < 1)
                                log_cmd_error("Must have at least one element on the stack for operator %%co.\n");
                        select_op_expand(design, arg, 'o');
                } else
                        log_cmd_error("Unknown selection operator '%s'.\n", arg.c_str());
                if (work_stack.size() >= 1)
                        select_filter_active_mod(design, work_stack.back());
                return;
        }

        if (arg[0] == '@') {
                std::string set_name = RTLIL::escape_id(arg.substr(1));
                if (design->selection_vars.count(set_name) > 0)
                        work_stack.push_back(design->selection_vars[set_name]);
                else
                        log_cmd_error("Selection @%s is not defined!\n", RTLIL::unescape_id(set_name).c_str());
                select_filter_active_mod(design, work_stack.back());
                return;
        }

        if (!design->selected_active_module.empty()) {
                arg_mod = design->selected_active_module;
                arg_memb = arg;
        } else {
                size_t pos = arg.find('/');
                if (pos == std::string::npos) {
                        if (arg.find(':') == std::string::npos || arg.substr(0, 1) == "A")
                                arg_mod = arg;
                        else
                                arg_mod = "*", arg_memb = arg;
                } else {
                        arg_mod = arg.substr(0, pos);
                        arg_memb = arg.substr(pos+1);
                }
        }

        work_stack.push_back(RTLIL::Selection());
        RTLIL::Selection &sel = work_stack.back();

        if (arg == "*" && arg_mod == "*") {
                select_filter_active_mod(design, work_stack.back());
                return;
        }
        
        sel.full_selection = false;
        for (auto &mod_it : design->modules_)
        {
                if (arg_mod.substr(0, 2) == "A:") {
                        if (!match_attr(mod_it.second->attributes, arg_mod.substr(2)))
                                continue;
                } else
                if (!match_ids(mod_it.first, arg_mod))
                        continue;

                if (arg_memb == "") {
                        sel.selected_modules.insert(mod_it.first);
                        continue;
                }

                RTLIL::Module *mod = mod_it.second;
                if (arg_memb.substr(0, 2) == "w:") {
                        for (auto &it : mod->wires_)
                                if (match_ids(it.first, arg_memb.substr(2)))
                                        sel.selected_members[mod->name].insert(it.first);
                } else
                if (arg_memb.substr(0, 2) == "i:") {
                        for (auto &it : mod->wires_)
                                if (it.second->port_input && match_ids(it.first, arg_memb.substr(2)))
                                        sel.selected_members[mod->name].insert(it.first);
                } else
                if (arg_memb.substr(0, 2) == "o:") {
                        for (auto &it : mod->wires_)
                                if (it.second->port_output && match_ids(it.first, arg_memb.substr(2)))
                                        sel.selected_members[mod->name].insert(it.first);
                } else
                if (arg_memb.substr(0, 2) == "x:") {
                        for (auto &it : mod->wires_)
                                if ((it.second->port_input || it.second->port_output) && match_ids(it.first, arg_memb.substr(2)))
                                        sel.selected_members[mod->name].insert(it.first);
                } else
                if (arg_memb.substr(0, 2) == "s:") {
                        size_t delim = arg_memb.substr(2).find(':');
                        if (delim == std::string::npos) {
                                int width = atoi(arg_memb.substr(2).c_str());
                                for (auto &it : mod->wires_)
                                        if (it.second->width == width)
                                                sel.selected_members[mod->name].insert(it.first);
                        } else {
                                std::string min_str = arg_memb.substr(2, delim);
                                std::string max_str = arg_memb.substr(2+delim+1);
                                int min_width = min_str.empty() ? 0 : atoi(min_str.c_str());
                                int max_width = max_str.empty() ? -1 : atoi(max_str.c_str());
                                for (auto &it : mod->wires_)
                                        if (min_width <= it.second->width && (it.second->width <= max_width || max_width == -1))
                                                sel.selected_members[mod->name].insert(it.first);
                        }
                } else
                if (arg_memb.substr(0, 2) == "m:") {
                        for (auto &it : mod->memories)
                                if (match_ids(it.first, arg_memb.substr(2)))
                                        sel.selected_members[mod->name].insert(it.first);
                } else
                if (arg_memb.substr(0, 2) == "c:") {
                        for (auto &it : mod->cells_)
                                if (match_ids(it.first, arg_memb.substr(2)))
                                        sel.selected_members[mod->name].insert(it.first);
                } else
                if (arg_memb.substr(0, 2) == "t:") {
                        for (auto &it : mod->cells_)
                                if (match_ids(it.second->type, arg_memb.substr(2)))
                                        sel.selected_members[mod->name].insert(it.first);
                } else
                if (arg_memb.substr(0, 2) == "p:") {
                        for (auto &it : mod->processes)
                                if (match_ids(it.first, arg_memb.substr(2)))
                                        sel.selected_members[mod->name].insert(it.first);
                } else
                if (arg_memb.substr(0, 2) == "a:") {
                        for (auto &it : mod->wires_)
                                if (match_attr(it.second->attributes, arg_memb.substr(2)))
                                        sel.selected_members[mod->name].insert(it.first);
                        for (auto &it : mod->memories)
                                if (match_attr(it.second->attributes, arg_memb.substr(2)))
                                        sel.selected_members[mod->name].insert(it.first);
                        for (auto &it : mod->cells_)
                                if (match_attr(it.second->attributes, arg_memb.substr(2)))
                                        sel.selected_members[mod->name].insert(it.first);
                        for (auto &it : mod->processes)
                                if (match_attr(it.second->attributes, arg_memb.substr(2)))
                                        sel.selected_members[mod->name].insert(it.first);
                } else
                if (arg_memb.substr(0, 2) == "r:") {
                        for (auto &it : mod->cells_)
                                if (match_attr(it.second->parameters, arg_memb.substr(2)))
                                        sel.selected_members[mod->name].insert(it.first);
                } else {
                        if (arg_memb.substr(0, 2) == "n:")
                                arg_memb = arg_memb.substr(2);
                        for (auto &it : mod->wires_)
                                if (match_ids(it.first, arg_memb))
                                        sel.selected_members[mod->name].insert(it.first);
                        for (auto &it : mod->memories)
                                if (match_ids(it.first, arg_memb))
                                        sel.selected_members[mod->name].insert(it.first);
                        for (auto &it : mod->cells_)
                                if (match_ids(it.first, arg_memb))
                                        sel.selected_members[mod->name].insert(it.first);
                        for (auto &it : mod->processes)
                                if (match_ids(it.first, arg_memb))
                                        sel.selected_members[mod->name].insert(it.first);
                }
        }

        select_filter_active_mod(design, work_stack.back());
}

// used in kernel/register.cc and maybe other locations, extern decl. in register.h
void handle_extra_select_args(Pass *pass, std::vector<std::string> args, size_t argidx, size_t args_size, RTLIL::Design *design)
{
        work_stack.clear();
        for (; argidx < args_size; argidx++) {
                if (args[argidx].substr(0, 1) == "-") {
                        if (pass != NULL)
                                pass->cmd_error(args, argidx, "Unexpected option in selection arguments.");
                        else
                                log_cmd_error("Unexpected option in selection arguments.");
                }
                select_stmt(design, args[argidx]);
        }
        while (work_stack.size() > 1) {
                select_op_union(design, work_stack.front(), work_stack.back());
                work_stack.pop_back();
        }
        if (work_stack.size() > 0)
                design->selection_stack.push_back(work_stack.back());
        else
                design->selection_stack.push_back(RTLIL::Selection(false));
}

struct SelectPass : public Pass {
        SelectPass() : Pass("select", "modify and view the list of selected objects") { }
        virtual void help()
        {
                //   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
                log("\n");
                log("    select [ -add | -del | -set <name> ] <selection>\n");
                log("    select [ -assert-none | -assert-any ] <selection>\n");
                log("    select [ -list | -write <filename> | -count | -clear ]\n");
                log("    select -module <modname>\n");
                log("\n");
                log("Most commands use the list of currently selected objects to determine which part\n");
                log("of the design to operate on. This command can be used to modify and view this\n");
                log("list of selected objects.\n");
                log("\n");
                log("Note that many commands support an optional [selection] argument that can be\n");
                log("used to override the global selection for the command. The syntax of this\n");
                log("optional argument is identical to the syntax of the <selection> argument\n");
                log("described here.\n");
                log("\n");
                log("    -add, -del\n");
                log("        add or remove the given objects to the current selection.\n");
                log("        without this options the current selection is replaced.\n");
                log("\n");
                log("    -set <name>\n");
                log("        do not modify the current selection. instead save the new selection\n");
                log("        under the given name (see @<name> below). to save the current selection,\n");
                log("        use \"select -set <name> %%\"\n");
                log("\n");
                log("    -assert-none\n");
                log("        do not modify the current selection. instead assert that the given\n");
                log("        selection is empty. i.e. produce an error if any object matching the\n");
                log("        selection is found.\n");
                log("\n");
                log("    -assert-any\n");
                log("        do not modify the current selection. instead assert that the given\n");
                log("        selection is non-empty. i.e. produce an error if no object matching\n");
                log("        the selection is found.\n");
                log("\n");
                log("    -assert-count N\n");
                log("        do not modify the current selection. instead assert that the given\n");
                log("        selection contains exactly N objects.\n");
                log("\n");
                log("    -list\n");
                log("        list all objects in the current selection\n");
                log("\n");
                log("    -write <filename>\n");
                log("        like -list but write the output to the specified file\n");
                log("\n");
                log("    -count\n");
                log("        count all objects in the current selection\n");
                log("\n");
                log("    -clear\n");
                log("        clear the current selection. this effectively selects the whole\n");
                log("        design. it also resets the selected module (see -module). use the\n");
                log("        command 'select *' to select everything but stay in the current module.\n");
                log("\n");
                log("    -none\n");
                log("        create an empty selection. the current module is unchanged.\n");
                log("\n");
                log("    -module <modname>\n");
                log("        limit the current scope to the specified module.\n");
                log("        the difference between this and simply selecting the module\n");
                log("        is that all object names are interpreted relative to this\n");
                log("        module after this command until the selection is cleared again.\n");
                log("\n");
                log("When this command is called without an argument, the current selection\n");
                log("is displayed in a compact form (i.e. only the module name when a whole module\n");
                log("is selected).\n");
                log("\n");
                log("The <selection> argument itself is a series of commands for a simple stack\n");
                log("machine. Each element on the stack represents a set of selected objects.\n");
                log("After this commands have been executed, the union of all remaining sets\n");
                log("on the stack is computed and used as selection for the command.\n");
                log("\n");
                log("Pushing (selecting) object when not in -module mode:\n");
                log("\n");
                log("    <mod_pattern>\n");
                log("        select the specified module(s)\n");
                log("\n");
                log("    <mod_pattern>/<obj_pattern>\n");
                log("        select the specified object(s) from the module(s)\n");
                log("\n");
                log("Pushing (selecting) object when in -module mode:\n");
                log("\n");
                log("    <obj_pattern>\n");
                log("        select the specified object(s) from the current module\n");
                log("\n");
                log("A <mod_pattern> can be a module name, wildcard expression (*, ?, [..])\n");
                log("matching module names, or one of the following:\n");
                log("\n");
                log("    A:<pattern>, A:<pattern>=<pattern>\n");
                log("        all modules with an attribute matching the given pattern\n");
                log("        in addition to = also <, <=, >=, and > are supported\n");
                log("\n");
                log("An <obj_pattern> can be an object name, wildcard expression, or one of\n");
                log("the following:\n");
                log("\n");
                log("    w:<pattern>\n");
                log("        all wires with a name matching the given wildcard pattern\n");
                log("\n");
                log("    i:<pattern>, o:<pattern>, x:<pattern>\n");
                log("        all inputs (i:), outputs (o:) or any ports (x:) with matching names\n");
                log("\n");
                log("    s:<size>, s:<min>:<max>\n");
                log("        all wires with a matching width\n");
                log("\n");
                log("    m:<pattern>\n");
                log("        all memories with a name matching the given pattern\n");
                log("\n");
                log("    c:<pattern>\n");
                log("        all cells with a name matching the given pattern\n");
                log("\n");
                log("    t:<pattern>\n");
                log("        all cells with a type matching the given pattern\n");
                log("\n");
                log("    p:<pattern>\n");
                log("        all processes with a name matching the given pattern\n");
                log("\n");
                log("    a:<pattern>\n");
                log("        all objects with an attribute name matching the given pattern\n");
                log("\n");
                log("    a:<pattern>=<pattern>\n");
                log("        all objects with a matching attribute name-value-pair.\n");
                log("        in addition to = also <, <=, >=, and > are supported\n");
                log("\n");
                log("    r:<pattern>, r:<pattern>=<pattern>\n");
                log("        cells with matching parameters. also with <, <=, >= and >.\n");
                log("\n");
                log("    n:<pattern>\n");
                log("        all objects with a name matching the given pattern\n");
                log("        (i.e. 'n:' is optional as it is the default matching rule)\n");
                log("\n");
                log("    @<name>\n");
                log("        push the selection saved prior with 'select -set <name> ...'\n");
                log("\n");
                log("The following actions can be performed on the top sets on the stack:\n");
                log("\n");
                log("    %%\n");
                log("        push a copy of the current selection to the stack\n");
                log("\n");
                log("    %%%%\n");
                log("        replace the stack with a union of all elements on it\n");
                log("\n");
                log("    %%n\n");
                log("        replace top set with its invert\n");
                log("\n");
                log("    %%u\n");
                log("        replace the two top sets on the stack with their union\n");
                log("\n");
                log("    %%i\n");
                log("        replace the two top sets on the stack with their intersection\n");
                log("\n");
                log("    %%d\n");
                log("        pop the top set from the stack and subtract it from the new top\n");
                log("\n");
                log("    %%D\n");
                log("        like %%d but swap the roles of two top sets on the stack\n");
                log("\n");
                log("    %%c\n");
                log("        create a copy of the top set rom the stack and push it\n");
                log("\n");
                log("    %%x[<num1>|*][.<num2>][:<rule>[:<rule>..]]\n");
                log("        expand top set <num1> num times according to the specified rules.\n");
                log("        (i.e. select all cells connected to selected wires and select all\n");
                log("        wires connected to selected cells) The rules specify which cell\n");
                log("        ports to use for this. the syntax for a rule is a '-' for exclusion\n");
                log("        and a '+' for inclusion, followed by an optional comma seperated\n");
                log("        list of cell types followed by an optional comma separated list of\n");
                log("        cell ports in square brackets. a rule can also be just a cell or wire\n");
                log("        name that limits the expansion (is included but does not go beyond).\n");
                log("        select at most <num2> objects. a warning message is printed when this\n");
                log("        limit is reached. When '*' is used instead of <num1> then the process\n");
                log("        is repeated until no further object are selected.\n");
                log("\n");
                log("    %%ci[<num1>|*][.<num2>][:<rule>[:<rule>..]]\n");
                log("    %%co[<num1>|*][.<num2>][:<rule>[:<rule>..]]\n");
                log("        simmilar to %%x, but only select input (%%ci) or output cones (%%co)\n");
                log("\n");
                log("    %%a\n");
                log("        expand top set by selecting all wires that are (at least in part)\n");
                log("        aliases for selected wires.\n");
                log("\n");
                log("    %%s\n");
                log("        expand top set by adding all modules of instantiated cells in selected\n");
                log("        modules\n");
                log("\n");
                log("    %%m\n");
                log("        expand top set by selecting all modules that contain selected objects\n");
                log("\n");
                log("Example: the following command selects all wires that are connected to a\n");
                log("'GATE' input of a 'SWITCH' cell:\n");
                log("\n");
                log("    select */t:SWITCH %%x:+[GATE] */t:SWITCH %%d\n");
                log("\n");
        }
        virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
        {
                bool add_mode = false;
                bool del_mode = false;
                bool clear_mode = false;
                bool none_mode = false;
                bool list_mode = false;
                bool count_mode = false;
                bool got_module = false;
                bool assert_none = false;
                bool assert_any = false;
                int assert_count = -1;
                std::string write_file;
                std::string set_name;
                std::string sel_str;

                work_stack.clear();

                size_t argidx;
                for (argidx = 1; argidx < args.size(); argidx++)
                {
                        std::string arg = args[argidx];
                        if (arg == "-add") {
                                add_mode = true;
                                continue;
                        }
                        if (arg == "-del") {
                                del_mode = true;
                                continue;
                        }
                        if (arg == "-assert-none") {
                                assert_none = true;
                                continue;
                        }
                        if (arg == "-assert-any") {
                                assert_any = true;
                                continue;
                        }
                        if (arg == "-assert-count" && argidx+1 < args.size()) {
                                assert_count = atoi(args[++argidx].c_str());
                                continue;
                        }
                        if (arg == "-clear") {
                                clear_mode = true;
                                continue;
                        }
                        if (arg == "-none") {
                                none_mode = true;
                                continue;
                        }
                        if (arg == "-list") {
                                list_mode = true;
                                continue;
                        }
                        if (arg == "-write" && argidx+1 < args.size()) {
                                write_file = args[++argidx];
                                continue;
                        }
                        if (arg == "-count") {
                                count_mode = true;
                                continue;
                        }
                        if (arg == "-module" && argidx+1 < args.size()) {
                                RTLIL::IdString mod_name = RTLIL::escape_id(args[++argidx]);
                                if (design->modules_.count(mod_name) == 0)
                                        log_cmd_error("No such module: %s\n", id2cstr(mod_name));
                                design->selected_active_module = mod_name;
                                got_module = true;
                                continue;
                        }
                        if (arg == "-set" && argidx+1 < args.size()) {
                                set_name = RTLIL::escape_id(args[++argidx]);
                                continue;
                        }
                        if (arg.size() > 0 && arg[0] == '-')
                                log_cmd_error("Unkown option %s.\n", arg.c_str());
                        select_stmt(design, arg);
                        sel_str += " " + arg;
                }

                if (clear_mode && args.size() != 2)
                        log_cmd_error("Option -clear can not be combined with any other options.\n");

                if (none_mode && args.size() != 2)
                        log_cmd_error("Option -none can not be combined with any other options.\n");

                if (add_mode + del_mode + assert_none + assert_any + (assert_count >= 0) > 1)
                        log_cmd_error("Options -add, -del, -assert-none, -assert-any or -assert-count can not be combined.\n");

                if ((list_mode || !write_file.empty() || count_mode) && (add_mode || del_mode || assert_none || assert_any || assert_count >= 0))
                        log_cmd_error("Options -list, -write and -count can not be combined with -add, -del, -assert-none, -assert-any or -assert-count.\n");

                if (!set_name.empty() && (list_mode || !write_file.empty() || count_mode || add_mode || del_mode || assert_none || assert_any || assert_count >= 0))
                        log_cmd_error("Option -set can not be combined with -list, -write, -count, -add, -del, -assert-none, -assert-any or -assert-count.\n");

                if (work_stack.size() == 0 && got_module) {
                        RTLIL::Selection sel;
                        select_filter_active_mod(design, sel);
                        work_stack.push_back(sel);
                }

                while (work_stack.size() > 1) {
                        select_op_union(design, work_stack.front(), work_stack.back());
                        work_stack.pop_back();
                }

                log_assert(design->selection_stack.size() > 0);

                if (clear_mode) {
                        design->selection_stack.back() = RTLIL::Selection(true);
                        design->selected_active_module = std::string();
                        return;
                }

                if (none_mode) {
                        design->selection_stack.back() = RTLIL::Selection(false);
                        return;
                }

                if (list_mode || count_mode || !write_file.empty())
                {
                #define LOG_OBJECT(...) do { if (list_mode) log(__VA_ARGS__); if (f != NULL) fprintf(f, __VA_ARGS__); total_count++; } while (0)
                        int total_count = 0;
                        FILE *f = NULL;
                        if (!write_file.empty()) {
                                f = fopen(write_file.c_str(), "w");
                                if (f == NULL)
                                        log_error("Can't open '%s' for writing: %s\n", write_file.c_str(), strerror(errno));
                        }
                        RTLIL::Selection *sel = &design->selection_stack.back();
                        if (work_stack.size() > 0)
                                sel = &work_stack.back();
                        sel->optimize(design);
                        for (auto mod_it : design->modules_)
                        {
                                if (sel->selected_whole_module(mod_it.first) && list_mode)
                                        log("%s\n", id2cstr(mod_it.first));
                                if (sel->selected_module(mod_it.first)) {
                                        for (auto &it : mod_it.second->wires_)
                                                if (sel->selected_member(mod_it.first, it.first))
                                                        LOG_OBJECT("%s/%s\n", id2cstr(mod_it.first), id2cstr(it.first));
                                        for (auto &it : mod_it.second->memories)
                                                if (sel->selected_member(mod_it.first, it.first))
                                                        LOG_OBJECT("%s/%s\n", id2cstr(mod_it.first), id2cstr(it.first));
                                        for (auto &it : mod_it.second->cells_)
                                                if (sel->selected_member(mod_it.first, it.first))
                                                        LOG_OBJECT("%s/%s\n", id2cstr(mod_it.first), id2cstr(it.first));
                                        for (auto &it : mod_it.second->processes)
                                                if (sel->selected_member(mod_it.first, it.first))
                                                        LOG_OBJECT("%s/%s\n", id2cstr(mod_it.first), id2cstr(it.first));
                                }
                        }
                        if (count_mode)
                                log("%d objects.\n", total_count);
                        if (f != NULL)
                                fclose(f);
                #undef LOG_OBJECT
                        return;
                }

                if (add_mode)
                {
                        if (work_stack.size() == 0)
                                log_cmd_error("Nothing to add to selection.\n");
                        select_op_union(design, design->selection_stack.back(), work_stack.back());
                        design->selection_stack.back().optimize(design);
                        return;
                }

                if (del_mode)
                {
                        if (work_stack.size() == 0)
                                log_cmd_error("Nothing to delete from selection.\n");
                        select_op_diff(design, design->selection_stack.back(), work_stack.back());
                        design->selection_stack.back().optimize(design);
                        return;
                }

                if (assert_none)
                {
                        if (work_stack.size() == 0)
                                log_cmd_error("No selection to check.\n");
                        if (!work_stack.back().empty())
                                log_error("Assertation failed: selection is not empty:%s\n", sel_str.c_str());
                        return;
                }

                if (assert_any)
                {
                        if (work_stack.size() == 0)
                                log_cmd_error("No selection to check.\n");
                        if (work_stack.back().empty())
                                log_error("Assertation failed: selection is empty:%s\n", sel_str.c_str());
                        return;
                }

                if (assert_count >= 0)
                {
                        int total_count = 0;
                        if (work_stack.size() == 0)
                                log_cmd_error("No selection to check.\n");
                        RTLIL::Selection *sel = &work_stack.back();
                        sel->optimize(design);
                        for (auto mod_it : design->modules_)
                                if (sel->selected_module(mod_it.first)) {
                                        for (auto &it : mod_it.second->wires_)
                                                if (sel->selected_member(mod_it.first, it.first))
                                                        total_count++;
                                        for (auto &it : mod_it.second->memories)
                                                if (sel->selected_member(mod_it.first, it.first))
                                                        total_count++;
                                        for (auto &it : mod_it.second->cells_)
                                                if (sel->selected_member(mod_it.first, it.first))
                                                        total_count++;
                                        for (auto &it : mod_it.second->processes)
                                                if (sel->selected_member(mod_it.first, it.first))
                                                        total_count++;
                                }
                        if (assert_count != total_count)
                                log_error("Assertation failed: selection contains %d elements instead of the asserted %d:%s\n",
                                                total_count, assert_count, sel_str.c_str());
                        return;
                }

                if (!set_name.empty())
                {
                        if (work_stack.size() == 0)
                                design->selection_vars[set_name] = RTLIL::Selection(false);
                        else
                                design->selection_vars[set_name] = work_stack.back();
                        return;
                }

                if (work_stack.size() == 0) {
                        RTLIL::Selection &sel = design->selection_stack.back();
                        if (sel.full_selection)
                                log("*\n");
                        for (auto &it : sel.selected_modules)
                                log("%s\n", id2cstr(it));
                        for (auto &it : sel.selected_members)
                                for (auto &it2 : it.second)
                                        log("%s/%s\n", id2cstr(it.first), id2cstr(it2));
                        return;
                }

                design->selection_stack.back() = work_stack.back();
                design->selection_stack.back().optimize(design);
        }
} SelectPass;
 
struct CdPass : public Pass {
        CdPass() : Pass("cd", "a shortcut for 'select -module <name>'") { }
        virtual void help()
        {
                //   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
                log("\n");
                log("    cd <modname>\n");
                log("\n");
                log("This is just a shortcut for 'select -module <modname>'.\n");
                log("\n");
                log("\n");
                log("    cd <cellname>\n");
                log("\n");
                log("When no module with the specified name is found, but there is a cell\n");
                log("with the specified name in the current module, then this is equivialent\n");
                log("to 'cd <celltype>'.\n");
                log("\n");
                log("    cd ..\n");
                log("\n");
                log("This is just a shortcut for 'select -clear'.\n");
                log("\n");
        }
        virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
        {
                if (args.size() != 2)
                        log_cmd_error("Invalid number of arguments.\n");

                if (args[1] == "..") {
                        design->selection_stack.back() = RTLIL::Selection(true);
                        design->selected_active_module = std::string();
                        return;
                }

                std::string modname = RTLIL::escape_id(args[1]);

                if (design->modules_.count(modname) == 0 && !design->selected_active_module.empty()) {
                        RTLIL::Module *module = NULL;
                        if (design->modules_.count(design->selected_active_module) > 0)
                                module = design->modules_.at(design->selected_active_module);
                        if (module != NULL && module->cells_.count(modname) > 0)
                                modname = module->cells_.at(modname)->type;
                }

                if (design->modules_.count(modname) > 0) {
                        design->selected_active_module = modname;
                        design->selection_stack.back() = RTLIL::Selection();
                        select_filter_active_mod(design, design->selection_stack.back());
                        design->selection_stack.back().optimize(design);
                        return;
                }

                log_cmd_error("No such module `%s' found!\n", RTLIL::unescape_id(modname).c_str());
        }
} CdPass;

template<typename T>
static int log_matches(const char *title, std::string pattern, T list)
{
        std::vector<RTLIL::IdString> matches;

        for (auto &it : list)
                if (pattern.empty() || match_ids(it.first, pattern))
                        matches.push_back(it.first);

        if (matches.empty())
                return 0;

        log("\n%d %s:\n", int(matches.size()), title);
        for (auto &id : matches)
                log("  %s\n", RTLIL::id2cstr(id));
        return matches.size();
}
 
struct LsPass : public Pass {
        LsPass() : Pass("ls", "list modules or objects in modules") { }
        virtual void help()
        {
                //   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
                log("\n");
                log("    ls [pattern]\n");
                log("\n");
                log("When no active module is selected, this prints a list of all modules.\n");
                log("\n");
                log("When an active module is selected, this prints a list of objects in the module.\n");
                log("\n");
                log("If a pattern is given, the objects matching the pattern are printed\n");
                log("\n");
                log("Note that this command does not use the selection mechanism and always operates\n");
                log("on the whole design or whole active module. Use 'select -list' to show a list\n");
                log("of currently selected objects.\n");
                log("\n");
        }
        virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
        {
                std::string pattern;
                int counter = 0;

                if (args.size() != 1 && args.size() != 2)
                        log_cmd_error("Invalid number of arguments.\n");
                if (args.size() == 2)
                        pattern = args.at(1);

                if (design->selected_active_module.empty())
                {
                        counter += log_matches("modules", pattern, design->modules_);
                }
                else
                if (design->modules_.count(design->selected_active_module) > 0)
                {
                        RTLIL::Module *module = design->modules_.at(design->selected_active_module);
                        counter += log_matches("wires", pattern, module->wires_);
                        counter += log_matches("memories", pattern, module->memories);
                        counter += log_matches("cells", pattern, module->cells_);
                        counter += log_matches("processes", pattern, module->processes);
                }

                // log("\nfound %d item%s.\n", counter, counter == 1 ? "" : "s");
        }
} LsPass;