From a342d6db49b812efa1457f39dc9713bcda3d54ce Mon Sep 17 00:00:00 2001 From: whitequark Date: Mon, 7 Jan 2019 00:11:49 +0000 Subject: [PATCH] bugpoint: new pass. A typical use of `bugpoint` would involve a script with a pass under test, e.g.: flowmap -relax -optarea 100 and would be invoked as: bugpoint -yosys ./yosys -script flowmap.ys -clean -cells This replaces the current design with the minimal design that still crashes the `flowmap.ys` script. `bugpoint` can also be used to perform generic design minimization using `select`, e.g. the following script: select i:* %x t:$_MUX_ %i -assert-max 0 would remove all parts of the design except for an unbroken path from an input to an output port that goes through exactly one $_MUX_ cell. (The condition is inverted.) --- passes/cmds/Makefile.inc | 2 +- passes/cmds/bugpoint.cc | 369 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 370 insertions(+), 1 deletion(-) create mode 100644 passes/cmds/bugpoint.cc diff --git a/passes/cmds/Makefile.inc b/passes/cmds/Makefile.inc index 44a83b2b9..c8067a8be 100644 --- a/passes/cmds/Makefile.inc +++ b/passes/cmds/Makefile.inc @@ -29,4 +29,4 @@ OBJS += passes/cmds/chformal.o OBJS += passes/cmds/chtype.o OBJS += passes/cmds/blackbox.o OBJS += passes/cmds/ltp.o - +OBJS += passes/cmds/bugpoint.o diff --git a/passes/cmds/bugpoint.cc b/passes/cmds/bugpoint.cc new file mode 100644 index 000000000..736e94274 --- /dev/null +++ b/passes/cmds/bugpoint.cc @@ -0,0 +1,369 @@ +/* + * yosys -- Yosys Open SYnthesis Suite + * + * Copyright (C) 2018 whitequark + * + * 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/yosys.h" +#include "backends/ilang/ilang_backend.h" + +USING_YOSYS_NAMESPACE +using namespace ILANG_BACKEND; +PRIVATE_NAMESPACE_BEGIN + +struct BugpointPass : public Pass { + BugpointPass() : Pass("bugpoint", "minimize testcases") { } + void help() YS_OVERRIDE + { + // |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---| + log("\n"); + log(" bugpoint [options]\n"); + log("\n"); + log("This command minimizes testcases that crash Yosys. It removes an arbitrary part\n"); + log("of the design and recursively invokes Yosys with a given script, repeating these\n"); + log("steps while it can find a smaller design that still causes a crash. Once this\n"); + log("command finishes, it replaces the current design with the smallest testcase it\n"); + log("was able to produce.\n"); + log("\n"); + log("It is possible to specify the kinds of design part that will be removed. If none\n"); + log("are specified, all parts of design will be removed.\n"); + log("\n"); + log(" -yosys \n"); + log(" use this Yosys binary. if not specified, `yosys` is used.\n"); + log("\n"); + log(" -script \n"); + log(" use this script to crash Yosys. required.\n"); + log("\n"); + log(" -grep \n"); + log(" only consider crashes that place this string in the log file.\n"); + log("\n"); + log(" -fast\n"); + log(" run `clean -purge` after each minimization step. converges faster, but\n"); + log(" produces larger testcases, and may fail to produce any testcase at all if\n"); + log(" the crash is related to dangling wires.\n"); + log("\n"); + log(" -clean\n"); + log(" run `clean -purge` before checking testcase and after finishing. produces\n"); + log(" smaller and more useful testcases, but may fail to produce any testcase\n"); + log(" at all if the crash is related to dangling wires.\n"); + log("\n"); + log(" -modules\n"); + log(" try to remove modules.\n"); + log("\n"); + log(" -ports\n"); + log(" try to remove module ports.\n"); + log("\n"); + log(" -cells\n"); + log(" try to remove cells.\n"); + log("\n"); + log(" -connections\n"); + log(" try to reconnect ports to 'x.\n"); + log("\n"); + } + + bool run_yosys(RTLIL::Design *design, string yosys_cmd, string script) + { + design->sort(); + + std::ofstream f("bugpoint-case.il"); + ILANG_BACKEND::dump_design(f, design, /*only_selected=*/false, /*flag_m=*/true, /*flag_n=*/false); + f.close(); + + string yosys_cmdline = stringf("%s -qq -L bugpoint-case.log -s %s bugpoint-case.il", yosys_cmd.c_str(), script.c_str()); + return system(yosys_cmdline.c_str()) == 0; + } + + bool check_logfile(string grep) + { + if (grep.empty()) + return true; + + std::ifstream f("bugpoint-case.log"); + while (!f.eof()) + { + string line; + getline(f, line); + if (line.find(grep) != std::string::npos) + return true; + } + return false; + } + + RTLIL::Design *clean_design(RTLIL::Design *design, bool do_clean = true, bool do_delete = false) + { + if (!do_clean) + return design; + + RTLIL::Design *design_copy = new RTLIL::Design; + for (auto &it : design->modules_) + design_copy->add(it.second->clone()); + Pass::call(design_copy, "clean -purge"); + + if (do_delete) + delete design; + return design_copy; + } + + RTLIL::Design *simplify_something(RTLIL::Design *design, int &seed, bool stage2, bool modules, bool ports, bool cells, bool connections) + { + RTLIL::Design *design_copy = new RTLIL::Design; + for (auto &it : design->modules_) + design_copy->add(it.second->clone()); + + int index = 0; + if (modules) + { + for (auto &it : design_copy->modules_) + { + if (it.second->get_bool_attribute("\\blackbox")) + continue; + + if (index++ == seed) + { + log("Trying to remove module %s.\n", it.first.c_str()); + design_copy->remove(it.second); + return design_copy; + } + } + } + if (ports) + { + for (auto mod : design_copy->modules()) + { + if (mod->get_bool_attribute("\\blackbox")) + continue; + + for (auto wire : mod->wires()) + { + if (!stage2 && wire->get_bool_attribute("$bugpoint")) + continue; + + if (wire->port_input || wire->port_output) + { + if (index++ == seed) + { + log("Trying to remove module port %s.\n", log_signal(wire)); + wire->port_input = wire->port_output = false; + mod->fixup_ports(); + return design_copy; + } + } + } + } + } + if (cells) + { + for (auto mod : design_copy->modules()) + { + if (mod->get_bool_attribute("\\blackbox")) + continue; + + for (auto &it : mod->cells_) + { + if (index++ == seed) + { + log("Trying to remove cell %s.%s.\n", mod->name.c_str(), it.first.c_str()); + mod->remove(it.second); + return design_copy; + } + } + } + } + if (connections) + { + for (auto mod : design_copy->modules()) + { + if (mod->get_bool_attribute("\\blackbox")) + continue; + + for (auto cell : mod->cells()) + { + for (auto it : cell->connections_) + { + RTLIL::SigSpec port = cell->getPort(it.first); + bool is_undef = port.is_fully_undef(); + bool is_port = port.is_wire() && (port.as_wire()->port_input || port.as_wire()->port_output); + + if(is_undef || (!stage2 && is_port)) + continue; + + if (index++ == seed) + { + log("Trying to remove cell port %s.%s.%s.\n", mod->name.c_str(), cell->name.c_str(), it.first.c_str()); + RTLIL::SigSpec port_x(State::Sx, port.size()); + cell->unsetPort(it.first); + cell->setPort(it.first, port_x); + return design_copy; + } + + if (!stage2 && (cell->input(it.first) || cell->output(it.first)) && index++ == seed) + { + log("Trying to expose cell port %s.%s.%s as module port.\n", mod->name.c_str(), cell->name.c_str(), it.first.c_str()); + RTLIL::Wire *wire = mod->addWire(NEW_ID, port.size()); + wire->set_bool_attribute("$bugpoint"); + wire->port_input = cell->input(it.first); + wire->port_output = cell->output(it.first); + cell->unsetPort(it.first); + cell->setPort(it.first, wire); + mod->fixup_ports(); + return design_copy; + } + } + } + } + } + return NULL; + } + + void execute(std::vector args, RTLIL::Design *design) YS_OVERRIDE + { + string yosys_cmd = "yosys", script, grep; + bool fast = false, clean = false; + bool modules = false, ports = false, cells = false, connections = false, has_part = false; + + size_t argidx; + for (argidx = 1; argidx < args.size(); argidx++) + { + if (args[argidx] == "-yosys" && argidx + 1 < args.size()) { + yosys_cmd = args[++argidx]; + continue; + } + if (args[argidx] == "-script" && argidx + 1 < args.size()) { + script = args[++argidx]; + continue; + } + if (args[argidx] == "-grep" && argidx + 1 < args.size()) { + grep = args[++argidx]; + continue; + } + if (args[argidx] == "-fast") { + fast = true; + continue; + } + if (args[argidx] == "-clean") { + clean = true; + continue; + } + if (args[argidx] == "-modules") { + modules = true; + has_part = true; + continue; + } + if (args[argidx] == "-ports") { + ports = true; + has_part = true; + continue; + } + if (args[argidx] == "-cells") { + cells = true; + has_part = true; + continue; + } + if (args[argidx] == "-connections") { + connections = true; + has_part = true; + continue; + } + break; + } + extra_args(args, argidx, design); + + if (!has_part) + { + modules = true; + ports = true; + cells = true; + connections = true; + } + + if (!design->full_selection()) + log_cmd_error("This command only operates on fully selected designs!\n"); + + RTLIL::Design *crashing_design = clean_design(design, clean); + if (run_yosys(crashing_design, yosys_cmd, script)) + log_cmd_error("The provided script file and Yosys binary do not crash on this design!\n"); + if (!check_logfile(grep)) + log_cmd_error("The provided grep string is not found in the log file!\n"); + + int seed = 0, crashing_seed = seed; + bool found_something = false, stage2 = false; + while (true) + { + if (RTLIL::Design *simplified = simplify_something(crashing_design, seed, stage2, modules, ports, cells, connections)) + { + simplified = clean_design(simplified, fast, /*do_delete=*/true); + + bool crashes; + if (clean) + { + RTLIL::Design *testcase = clean_design(simplified); + crashes = !run_yosys(testcase, yosys_cmd, script); + delete testcase; + } + else + { + crashes = !run_yosys(simplified, yosys_cmd, script); + } + + if (crashes && check_logfile(grep)) + { + log("Testcase crashes.\n"); + if (crashing_design != design) + delete crashing_design; + crashing_design = simplified; + crashing_seed = seed; + found_something = true; + } + else + { + log("Testcase does not crash.\n"); + delete simplified; + seed++; + } + } + else + { + seed = 0; + if (found_something) + found_something = false; + else + { + if (!stage2) + { + log("Demoting introduced module ports.\n"); + stage2 = true; + } + else + { + log("Simplifications exhausted.\n"); + break; + } + } + } + } + + if (crashing_design != design) + { + Pass::call(design, "design -reset"); + crashing_design = clean_design(crashing_design, clean, /*do_delete=*/true); + for (auto &it : crashing_design->modules_) + design->add(it.second->clone()); + delete crashing_design; + } + } +} BugpointPass; + +PRIVATE_NAMESPACE_END -- 2.30.2