Merge pull request #4986 from jix/faster-liberty-caching

Liberty file caching with new `libcache` command

frontends/liberty/liberty.cc

@@ -539,7 +539,7 @@ struct LibertyFrontend : public Frontend {
 
 		log_header(design, "Executing Liberty frontend: %s\n", filename.c_str());
 
-		LibertyParser parser(*f);
+		LibertyParser parser(*f, filename);
 		int cell_count = 0;
 
 		std::map<std::string, std::tuple<int, int, bool>> global_type_map;

passes/cmds/stat.cc

@@ -352,7 +352,7 @@ void read_liberty_cellarea(dict<IdString, cell_area_t> &cell_area, string libert
 	yosys_input_files.insert(liberty_file);
 	if (f->fail())
 		log_cmd_error("Can't open liberty file `%s': %s\n", liberty_file.c_str(), strerror(errno));
-	LibertyParser libparser(*f);
+	LibertyParser libparser(*f, liberty_file);
 	delete f;
 
 	for (auto cell : libparser.ast->children)

passes/techmap/Makefile.inc

@@ -6,6 +6,7 @@ OBJS += passes/techmap/dfflibmap.o
 OBJS += passes/techmap/maccmap.o
 OBJS += passes/techmap/booth.o
 OBJS += passes/techmap/libparse.o
+OBJS += passes/techmap/libcache.o
 
 ifeq ($(ENABLE_ABC),1)
 OBJS += passes/techmap/abc.o

passes/techmap/clockgate.cc

@@ -312,7 +312,7 @@ struct ClockgatePass : public Pass {
 				std::istream* f = uncompressed(path);
 				if (f->fail())
 					log_cmd_error("Can't open liberty file `%s': %s\n", path.c_str(), strerror(errno));
-				LibertyParser p(*f);
+				LibertyParser p(*f, path);
 				merged.merge(p);
 				delete f;
 			}

passes/techmap/dfflibmap.cc

@@ -634,7 +634,7 @@ struct DfflibmapPass : public Pass {
 			std::istream* f = uncompressed(path);
 			if (f->fail())
 				log_cmd_error("Can't open liberty file `%s': %s\n", path.c_str(), strerror(errno));
-			LibertyParser p(*f);
+			LibertyParser p(*f, path);
 			merged.merge(p);
 			delete f;
 		}

passes/techmap/libcache.cc

@@ -0,0 +1,130 @@
+/*
+ *  yosys -- Yosys Open SYnthesis Suite
+ *
+ *  Copyright (C) 2025  Jannis Harder <jix@yosyshq.com> <me@jix.one>
+ *
+ *  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 "passes/techmap/libparse.h"
+
+ USING_YOSYS_NAMESPACE
+ PRIVATE_NAMESPACE_BEGIN
+
+ struct LibcachePass : public Pass {
+	LibcachePass() : Pass("libcache", "control caching of technology library data parsed from liberty files") { }
+	void help() override
+	{
+		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+		log("\n");
+		log("    libcache {-enable|-disable|-purge} { -all | [path]... }\n");
+		log("\n");
+		log("Controls the default and per path caching of liberty file data.\n");
+		log("\n");
+		log("    -enable    Enable caching.\n");
+		log("    -disable   Disable caching.\n");
+		log("    -purge     Reset cache setting and forget cached data.\n");
+		log("\n");
+		log("This mode takes a list of paths as argument. If no paths are provided, this\n");
+		log("command does nothing. The -all option can be used to change the default cache\n");
+		log("setting for -enable/-disable or to reset and forget about all paths.\n");
+		log("\n");
+		log("By default caching is disabled.\n");
+		log("\n");
+		log("    libcache -list\n");
+		log("\n");
+		log("Displays the current cache settings and cached paths.\n");
+		log("\n");
+	}
+	void execute(std::vector<std::string> args, RTLIL::Design *) override
+	{
+		bool enable = false;
+		bool disable = false;
+		bool purge = false;
+		bool all = false;
+		bool list = false;
+		std::vector<std::string> paths;
+
+		size_t argidx;
+		for (argidx = 1; argidx < args.size(); argidx++) {
+			if (args[argidx] == "-enable") {
+				enable = true;
+				continue;
+			}
+			if (args[argidx] == "-disable") {
+				enable = true;
+				continue;
+			}
+			if (args[argidx] == "-purge") {
+				purge = true;
+				continue;
+			}
+			if (args[argidx] == "-all") {
+				all = true;
+				continue;
+			}
+			if (args[argidx] == "-list") {
+				list = true;
+				continue;
+			}
+			std::string fname = args[argidx];
+			rewrite_filename(fname);
+			paths.push_back(fname);
+			break;
+		}
+		int modes = enable + disable + purge + list;
+		if (modes == 0)
+			log_cmd_error("At least one of -enable, -disable, -purge or -list is required.\n");
+		if (modes > 1)
+			log_cmd_error("Only one of -enable, -disable, -purge or -list may be present.\n");
+
+		if (all && !paths.empty())
+			log_cmd_error("The -all option cannot be combined with a list of paths.\n");
+		if (list && (all || !paths.empty()))
+			log_cmd_error("The -list mode takes no further options.\n");
+		if (!list && !all && paths.empty())
+			log("No paths specified, use -all to %s\n", purge ? "purge all paths" : "change the default setting");
+
+		if (list) {
+			log("Caching is %s by default.\n", LibertyAstCache::instance.cache_by_default ? "enabled" : "disabled");
+			for (auto const &entry : LibertyAstCache::instance.cache_path)
+				log("Caching is %s for `%s'.\n", entry.second ? "enabled" : "disabled", entry.first.c_str());
+			for (auto const &entry : LibertyAstCache::instance.cached)
+				log("Data for `%s' is currently cached.\n", entry.first.c_str());
+		} else if (enable || disable) {
+			if (all) {
+				LibertyAstCache::instance.cache_by_default = enable;
+			} else {
+				for (auto const &path : paths) {
+					LibertyAstCache::instance.cache_path[path] = enable;
+				}
+			}
+		} else if (purge) {
+			if (all) {
+				LibertyAstCache::instance.cached.clear();
+				LibertyAstCache::instance.cache_path.clear();
+			} else {
+				for (auto const &path : paths) {
+					LibertyAstCache::instance.cached.erase(path);
+					LibertyAstCache::instance.cache_path.erase(path);
+				}
+			}
+		} else {
+			log_assert(false);
+		}
+	}
+} LibcachePass;
+
+PRIVATE_NAMESPACE_END

passes/techmap/libparse.cc

@@ -32,6 +32,31 @@
 
 using namespace Yosys;
 
+#ifndef FILTERLIB
+
+LibertyAstCache LibertyAstCache::instance;
+
+std::shared_ptr<const LibertyAst> LibertyAstCache::cached_ast(const std::string &fname)
+{
+	auto it = cached.find(fname);
+	if (it == cached.end())
+		return nullptr;
+	log("Using cached data for liberty file `%s'\n", fname.c_str());
+	return it->second;
+}
+
+void LibertyAstCache::parsed_ast(const std::string &fname, const std::shared_ptr<const LibertyAst> &ast)
+{
+	auto it = cache_path.find(fname);
+	bool should_cache = it == cache_path.end() ? cache_by_default : it->second;
+	if (!should_cache)
+		return;
+	log("Caching data for liberty file `%s'\n", fname.c_str());
+	cached.emplace(fname, ast);
+}
+
+#endif
+
 bool LibertyInputStream::extend_buffer_once()
 {
 	if (eof)

passes/techmap/libparse.h

@@ -132,6 +132,22 @@ namespace Yosys
 		}
 	};
 
+#ifndef FILTERLIB
+	class LibertyAstCache {
+		LibertyAstCache() {};
+		~LibertyAstCache() {};
+	public:
+		dict<std::string, std::shared_ptr<const LibertyAst>> cached;
+
+		bool cache_by_default = false;
+		dict<std::string, bool> cache_path;
+
+		std::shared_ptr<const LibertyAst> cached_ast(const std::string &fname);
+		void parsed_ast(const std::string &fname, const std::shared_ptr<const LibertyAst> &ast);
+		static LibertyAstCache instance;
+	};
+#endif
+
 	class LibertyMergedCells;
 	class LibertyParser
 	{
@@ -152,15 +168,29 @@ namespace Yosys
 		void error(const std::string &str) const;
 
 	public:
-		const LibertyAst *ast;
+		std::shared_ptr<const LibertyAst> shared_ast;
+		const LibertyAst *ast = nullptr;
 
-		LibertyParser(std::istream &f) : f(f), line(1), ast(parse()) {}
+		LibertyParser(std::istream &f) : f(f), line(1) {
-		~LibertyParser() { if (ast) delete ast; }
+			shared_ast.reset(parse());
+			ast = shared_ast.get();
+		}
+
+#ifndef FILTERLIB
+		LibertyParser(std::istream &f, const std::string &fname) : f(f), line(1) {
+			shared_ast = LibertyAstCache::instance.cached_ast(fname);
+			if (!shared_ast) {
+				shared_ast.reset(parse());
+				LibertyAstCache::instance.parsed_ast(fname, shared_ast);
+			}
+			ast = shared_ast.get();
+		}
+#endif
 	};
 
 	class LibertyMergedCells
 	{
-		std::vector<const LibertyAst *> asts;
+		std::vector<std::shared_ptr<const LibertyAst>> asts;
 
 	public:
 		std::vector<const LibertyAst *> cells;
@@ -168,10 +198,7 @@ namespace Yosys
 		{
 			if (parser.ast) {
 				const LibertyAst *ast = parser.ast;
-				asts.push_back(ast);
+				asts.push_back(parser.shared_ast);
-				// The parser no longer owns its top level ast, but we do.
-				// sketchy zone
-				parser.ast = nullptr;
 				if (ast->id != "library")
 					parser.error("Top level entity isn't \"library\".\n");
 				for (const LibertyAst *cell : ast->children)
@@ -179,11 +206,6 @@ namespace Yosys
 						cells.push_back(cell);
 			}
 		}
-		~LibertyMergedCells()
-		{
-			for (auto ast : asts)
-				delete ast;
-		}
 	};
 
 }

tests/liberty/libcache.ys

@@ -0,0 +1,58 @@
+libcache -enable busdef.lib
+
+logger -expect log "Caching is disabled by default." 1
+logger -expect log "Caching is enabled for `busdef.lib'." 1
+libcache -list
+logger -check-expected
+
+logger -expect log "Caching data" 1
+log Caching data
+read_liberty normal.lib; design -reset
+logger -check-expected
+
+logger -expect log "Caching data" 1
+read_liberty -lib busdef.lib; design -reset
+logger -check-expected
+
+logger -expect log "Using caching data" 1
+log Using caching data
+read_liberty normal.lib; design -reset
+logger -check-expected
+
+logger -expect log "Using cached data" 1
+read_liberty -lib busdef.lib; design -reset
+logger -check-expected
+
+libcache -purge busdef.lib
+
+logger -expect log "Caching is disabled by default." 1
+logger -expect log "Caching is enabled for `busdef.lib'." 1
+log Caching is enabled for `busdef.lib'.
+libcache -list
+logger -check-expected
+
+libcache -enable -all
+
+logger -expect log "Caching is enabled by default." 1
+libcache -list
+logger -check-expected
+
+logger -expect log "Caching data" 1
+read_liberty normal.lib; design -reset
+logger -check-expected
+
+logger -expect log "Caching data" 1
+read_liberty -lib busdef.lib; design -reset
+logger -check-expected
+
+logger -expect log "Using cached data" 1
+read_liberty -lib busdef.lib; design -reset
+logger -check-expected
+
+logger -expect log "Using cached data" 1
+read_liberty normal.lib; design -reset
+logger -check-expected
+
+logger -expect log "Using cached data" 1
+dfflibmap -liberty normal.lib
+logger -check-expected