Merge https://github.com/cliffordwolf/yosys

118 files changed, 497 insertions, 202 deletions

diff --git a/backends/blif/blif.cc b/backends/blif/blif.cc
index 14b8b372e..27f08ea1a 100644
--- a/backends/blif/blif.cc
+++ b/backends/blif/blif.cc
@@ -317,6 +317,18 @@ struct BlifDumper
 				continue;
 			}
 
+			if (!config->icells_mode && cell->type == "$_DLATCH_N_") {
+				f << stringf(".latch %s %s al %s%s\n", cstr(cell->getPort("\\D")), cstr(cell->getPort("\\Q")),
+						cstr(cell->getPort("\\E")), cstr_init(cell->getPort("\\Q")));
+				continue;
+			}
+
+			if (!config->icells_mode && cell->type == "$_DLATCH_P_") {
+				f << stringf(".latch %s %s ah %s%s\n", cstr(cell->getPort("\\D")), cstr(cell->getPort("\\Q")),
+						cstr(cell->getPort("\\E")), cstr_init(cell->getPort("\\Q")));
+				continue;
+			}
+
 			if (!config->icells_mode && cell->type == "$lut") {
 				f << stringf(".names");
 				auto &inputs = cell->getPort("\\A");
@@ -448,7 +460,7 @@ struct BlifBackend : public Backend {
 		std::string false_type, false_out;
 		BlifDumperConfig config;
 
-		log_header("Executing BLIF backend.\n");
+		log_header(design, "Executing BLIF backend.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/backends/btor/btor.cc b/backends/btor/btor.cc
index 465723f1a..bbe90e85f 100644
--- a/backends/btor/btor.cc
+++ b/backends/btor/btor.cc
@@ -1065,7 +1065,7 @@ struct BtorBackend : public Backend {
 		std::string false_type, false_out;
 		BtorDumperConfig config;
 
-		log_header("Executing BTOR backend.\n");
+		log_header(design, "Executing BTOR backend.\n");
 
 		size_t argidx=1;
 		extra_args(f, filename, args, argidx);
diff --git a/backends/edif/edif.cc b/backends/edif/edif.cc
index 72bf07f53..d16f18316 100644
--- a/backends/edif/edif.cc
+++ b/backends/edif/edif.cc
@@ -113,7 +113,7 @@ struct EdifBackend : public Backend {
 	}
 	virtual void execute(std::ostream *&f, std::string filename, std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing EDIF backend.\n");
+		log_header(design, "Executing EDIF backend.\n");
 
 		std::string top_module_name;
 		std::map<RTLIL::IdString, std::map<RTLIL::IdString, int>> lib_cell_ports;
diff --git a/backends/ilang/ilang_backend.cc b/backends/ilang/ilang_backend.cc
index adabf05ec..03e29c524 100644
--- a/backends/ilang/ilang_backend.cc
+++ b/backends/ilang/ilang_backend.cc
@@ -391,7 +391,7 @@ struct IlangBackend : public Backend {
 	{
 		bool selected = false;
 
-		log_header("Executing ILANG backend.\n");
+		log_header(design, "Executing ILANG backend.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/backends/intersynth/intersynth.cc b/backends/intersynth/intersynth.cc
index 72a70e380..34cb52fb4 100644
--- a/backends/intersynth/intersynth.cc
+++ b/backends/intersynth/intersynth.cc
@@ -73,7 +73,7 @@ struct IntersynthBackend : public Backend {
 	}
 	virtual void execute(std::ostream *&f, std::string filename, std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing INTERSYNTH backend.\n");
+		log_header(design, "Executing INTERSYNTH backend.\n");
 		log_push();
 
 		std::vector<std::string> libfiles;
@@ -113,7 +113,7 @@ struct IntersynthBackend : public Backend {
 		}
 
 		if (libs.size() > 0)
-			log_header("Continuing INTERSYNTH backend.\n");
+			log_header(design, "Continuing INTERSYNTH backend.\n");
 
 		std::set<std::string> conntypes_code, celltypes_code;
 		std::string netlists_code;
diff --git a/backends/json/json.cc b/backends/json/json.cc
index 7d5ee58e8..05530ee69 100644
--- a/backends/json/json.cc
+++ b/backends/json/json.cc
@@ -463,7 +463,7 @@ struct JsonBackend : public Backend {
 		}
 		extra_args(f, filename, args, argidx);
 
-		log_header("Executing JSON backend.\n");
+		log_header(design, "Executing JSON backend.\n");
 
 		JsonWriter json_writer(*f, false, aig_mode);
 		json_writer.write_design(design);
diff --git a/backends/smt2/smt2.cc b/backends/smt2/smt2.cc
index c852921ee..e869f78cd 100644
--- a/backends/smt2/smt2.cc
+++ b/backends/smt2/smt2.cc
@@ -758,7 +758,7 @@ struct Smt2Backend : public Backend {
 		std::ifstream template_f;
 		bool bvmode = false, memmode = false, regsmode = false, wiresmode = false, verbose = false;
 
-		log_header("Executing SMT2 backend.\n");
+		log_header(design, "Executing SMT2 backend.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/backends/smv/smv.cc b/backends/smv/smv.cc
index b29a88ac2..162ce4906 100644
--- a/backends/smv/smv.cc
+++ b/backends/smv/smv.cc
@@ -694,7 +694,7 @@ struct SmvBackend : public Backend {
 		std::ifstream template_f;
 		bool verbose = false;
 
-		log_header("Executing SMV backend.\n");
+		log_header(design, "Executing SMV backend.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/backends/spice/spice.cc b/backends/spice/spice.cc
index bd54f16b9..4b88a3909 100644
--- a/backends/spice/spice.cc
+++ b/backends/spice/spice.cc
@@ -168,7 +168,7 @@ struct SpiceBackend : public Backend {
 		bool big_endian = false, use_inames = false;
 		std::string neg = "Vss", pos = "Vdd", ncpf = "_NC";
 
-		log_header("Executing SPICE backend.\n");
+		log_header(design, "Executing SPICE backend.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/backends/verilog/verilog_backend.cc b/backends/verilog/verilog_backend.cc
index 2d2b4bcfa..c5c6b5a08 100644
--- a/backends/verilog/verilog_backend.cc
+++ b/backends/verilog/verilog_backend.cc
@@ -1363,7 +1363,7 @@ struct VerilogBackend : public Backend {
 	}
 	virtual void execute(std::ostream *&f, std::string filename, std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing Verilog backend.\n");
+		log_header(design, "Executing Verilog backend.\n");
 
 		norename = false;
 		noattr = false;
diff --git a/frontends/ast/ast.cc b/frontends/ast/ast.cc
index 834ee82ab..64fd0a49c 100644
--- a/frontends/ast/ast.cc
+++ b/frontends/ast/ast.cc
@@ -146,6 +146,8 @@ std::string AST::type2str(AstNodeType type)
 	X(AST_ASSIGN_LE)
 	X(AST_CASE)
 	X(AST_COND)
+	X(AST_CONDX)
+	X(AST_CONDZ)
 	X(AST_DEFAULT)
 	X(AST_FOR)
 	X(AST_WHILE)
@@ -501,7 +503,12 @@ void AstNode::dumpVlog(FILE *f, std::string indent)
 		break;
 
 	case AST_CASE:
-		fprintf(f, "%s" "case (", indent.c_str());
+		if (!children.empty() && children[0]->type == AST_CONDX)
+			fprintf(f, "%s" "casex (", indent.c_str());
+		else if (!children.empty() && children[0]->type == AST_CONDZ)
+			fprintf(f, "%s" "casez (", indent.c_str());
+		else
+			fprintf(f, "%s" "case (", indent.c_str());
 		children[0]->dumpVlog(f, "");
 		fprintf(f, ")\n");
 		for (size_t i = 1; i < children.size(); i++) {
@@ -512,6 +519,8 @@ void AstNode::dumpVlog(FILE *f, std::string indent)
 		break;
 
 	case AST_COND:
+	case AST_CONDX:
+	case AST_CONDZ:
 		for (auto child : children) {
 			if (child->type == AST_BLOCK) {
 				fprintf(f, ":\n");
@@ -1033,7 +1042,7 @@ RTLIL::IdString AstModule::derive(RTLIL::Design *design, dict<RTLIL::IdString, R
 	if (stripped_name.substr(0, 9) == "$abstract")
 		stripped_name = stripped_name.substr(9);
 
-	log_header("Executing AST frontend in derive mode using pre-parsed AST for module `%s'.\n", stripped_name.c_str());
+	log_header(design, "Executing AST frontend in derive mode using pre-parsed AST for module `%s'.\n", stripped_name.c_str());
 
 	current_ast = NULL;
 	flag_dump_ast1 = false;
diff --git a/frontends/ast/ast.h b/frontends/ast/ast.h
index b5349db5e..b4e58d79f 100644
--- a/frontends/ast/ast.h
+++ b/frontends/ast/ast.h
@@ -122,6 +122,8 @@ namespace AST
 		AST_ASSIGN_LE,
 		AST_CASE,
 		AST_COND,
+		AST_CONDX,
+		AST_CONDZ,
 		AST_DEFAULT,
 		AST_FOR,
 		AST_WHILE,
diff --git a/frontends/ast/genrtlil.cc b/frontends/ast/genrtlil.cc
index 9fc590376..173930a1b 100644
--- a/frontends/ast/genrtlil.cc
+++ b/frontends/ast/genrtlil.cc
@@ -338,12 +338,14 @@ struct AST_INTERNAL::ProcessGenerator
 		case AST_CASE:
 			for (auto child : ast->children)
 				if (child != ast->children[0]) {
-					log_assert(child->type == AST_COND);
+					log_assert(child->type == AST_COND || child->type == AST_CONDX || child->type == AST_CONDZ);
 					collect_lvalues(reg, child, type_eq, type_le, false);
 				}
 			break;
 
 		case AST_COND:
+		case AST_CONDX:
+		case AST_CONDZ:
 		case AST_ALWAYS:
 		case AST_INITIAL:
 			for (auto child : ast->children)
@@ -467,7 +469,7 @@ struct AST_INTERNAL::ProcessGenerator
 				{
 					if (child == ast->children[0])
 						continue;
-					log_assert(child->type == AST_COND);
+					log_assert(child->type == AST_COND || child->type == AST_CONDX || child->type == AST_CONDZ);
 
 					subst_lvalue_map.save();
 					subst_rvalue_map.save();
diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc
index c56ac7d5f..e00087280 100644
--- a/frontends/ast/simplify.cc
+++ b/frontends/ast/simplify.cc
@@ -540,6 +540,18 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 		}
 	}
 
+	if (type == AST_CONDX && children.size() > 0 && children.at(0)->type == AST_CONSTANT) {
+		for (auto &bit : children.at(0)->bits)
+			if (bit == State::Sz || bit == State::Sx)
+				bit = State::Sa;
+	}
+
+	if (type == AST_CONDZ && children.size() > 0 && children.at(0)->type == AST_CONSTANT) {
+		for (auto &bit : children.at(0)->bits)
+			if (bit == State::Sz)
+				bit = State::Sa;
+	}
+
 	if (const_fold && type == AST_CASE)
 	{
 		while (children[0]->simplify(const_fold, at_zero, in_lvalue, stage, width_hint, sign_hint, in_param)) { }
@@ -548,7 +560,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 			new_children.push_back(children[0]);
 			for (int i = 1; i < GetSize(children); i++) {
 				AstNode *child = children[i];
-				log_assert(child->type == AST_COND);
+				log_assert(child->type == AST_COND || child->type == AST_CONDX || child->type == AST_CONDZ);
 				for (auto v : child->children) {
 					if (v->type == AST_DEFAULT)
 						goto keep_const_cond;
@@ -1125,7 +1137,7 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 		AstNode *selected_case = NULL;
 		for (size_t i = 1; i < children.size(); i++)
 		{
-			log_assert(children.at(i)->type == AST_COND);
+			log_assert(children.at(i)->type == AST_COND || children.at(i)->type == AST_CONDX || children.at(i)->type == AST_CONDZ);
 
 			AstNode *this_genblock = NULL;
 			for (auto child : children.at(i)->children) {
@@ -2984,7 +2996,7 @@ AstNode *AstNode::eval_const_function(AstNode *fcall)
 			for (size_t i = 1; i < stmt->children.size(); i++)
 			{
 				bool found_match = false;
-				log_assert(stmt->children.at(i)->type == AST_COND);
+				log_assert(stmt->children.at(i)->type == AST_COND || stmt->children.at(i)->type == AST_CONDX || stmt->children.at(i)->type == AST_CONDZ);
 
 				if (stmt->children.at(i)->children.front()->type == AST_DEFAULT) {
 					sel_case = stmt->children.at(i)->children.back();
diff --git a/frontends/blif/blifparse.cc b/frontends/blif/blifparse.cc
index ee0e771e9..a901e55f9 100644
--- a/frontends/blif/blifparse.cc
+++ b/frontends/blif/blifparse.cc
@@ -244,6 +244,10 @@ void parse_blif(RTLIL::Design *design, std::istream &f, std::string dff_name, bo
 					cell = module->addDff(NEW_ID, blif_wire(clock), blif_wire(d), blif_wire(q));
 				else if (!strcmp(edge, "fe"))
 					cell = module->addDff(NEW_ID, blif_wire(clock), blif_wire(d), blif_wire(q), false);
+				else if (!strcmp(edge, "ah"))
+					cell = module->addDlatch(NEW_ID, blif_wire(clock), blif_wire(d), blif_wire(q));
+				else if (!strcmp(edge, "al"))
+					cell = module->addDlatch(NEW_ID, blif_wire(clock), blif_wire(d), blif_wire(q), false);
 				else {
 			no_latch_clock:
 					cell = module->addCell(NEW_ID, dff_name);
@@ -399,7 +403,7 @@ struct BlifFrontend : public Frontend {
 	}
 	virtual void execute(std::istream *&f, std::string filename, std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing BLIF frontend.\n");
+		log_header(design, "Executing BLIF frontend.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/frontends/ilang/ilang_frontend.cc b/frontends/ilang/ilang_frontend.cc
index 7361a254b..ed6789987 100644
--- a/frontends/ilang/ilang_frontend.cc
+++ b/frontends/ilang/ilang_frontend.cc
@@ -47,7 +47,7 @@ struct IlangFrontend : public Frontend {
 	}
 	virtual void execute(std::istream *&f, std::string filename, std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing ILANG frontend.\n");
+		log_header(design, "Executing ILANG frontend.\n");
 		extra_args(f, filename, args, 1);
 		log("Input filename: %s\n", filename.c_str());
 
diff --git a/frontends/liberty/liberty.cc b/frontends/liberty/liberty.cc
index f02a73230..0be58b6da 100644
--- a/frontends/liberty/liberty.cc
+++ b/frontends/liberty/liberty.cc
@@ -437,7 +437,7 @@ struct LibertyFrontend : public Frontend {
 		bool flag_ignore_miss_dir  = false;
 		std::vector<std::string> attributes;
 
-		log_header("Executing Liberty frontend.\n");
+		log_header(design, "Executing Liberty frontend.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/frontends/verific/verific.cc b/frontends/verific/verific.cc
index b0fdedccd..7dd36a747 100644
--- a/frontends/verific/verific.cc
+++ b/frontends/verific/verific.cc
@@ -850,7 +850,7 @@ struct VerificPass : public Pass {
 #ifdef YOSYS_ENABLE_VERIFIC
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing VERIFIC (loading Verilog and VHDL designs using Verific).\n");
+		log_header(design, "Executing VERIFIC (loading Verilog and VHDL designs using Verific).\n");
 
 		Message::SetConsoleOutput(0);
 		Message::RegisterCallBackMsg(msg_func);
diff --git a/frontends/verilog/verilog_frontend.cc b/frontends/verilog/verilog_frontend.cc
index 11c2824c3..f8ccda181 100644
--- a/frontends/verilog/verilog_frontend.cc
+++ b/frontends/verilog/verilog_frontend.cc
@@ -186,7 +186,7 @@ struct VerilogFrontend : public Frontend {
 		formal_mode = false;
 		default_nettype_wire = true;
 
-		log_header("Executing Verilog-2005 frontend.\n");
+		log_header(design, "Executing Verilog-2005 frontend.\n");
 
 		args.insert(args.begin()+1, verilog_defaults.begin(), verilog_defaults.end());
 
diff --git a/frontends/verilog/verilog_parser.y b/frontends/verilog/verilog_parser.y
index 568cadd94..f95849133 100644
--- a/frontends/verilog/verilog_parser.y
+++ b/frontends/verilog/verilog_parser.y
@@ -1094,7 +1094,9 @@ case_body:
 
 case_item:
 	{
-		AstNode *node = new AstNode(AST_COND);
+		AstNode *node = new AstNode(
+				case_type_stack.size() && case_type_stack.back() == 'x' ? AST_CONDX :
+				case_type_stack.size() && case_type_stack.back() == 'z' ? AST_CONDZ : AST_COND);
 		ast_stack.back()->children.push_back(node);
 		ast_stack.push_back(node);
 	} case_select {
@@ -1114,7 +1116,9 @@ gen_case_body:
 
 gen_case_item:
 	{
-		AstNode *node = new AstNode(AST_COND);
+		AstNode *node = new AstNode(
+				case_type_stack.size() && case_type_stack.back() == 'x' ? AST_CONDX :
+				case_type_stack.size() && case_type_stack.back() == 'z' ? AST_CONDZ : AST_COND);
 		ast_stack.back()->children.push_back(node);
 		ast_stack.push_back(node);
 	} case_select {
diff --git a/frontends/vhdl2verilog/vhdl2verilog.cc b/frontends/vhdl2verilog/vhdl2verilog.cc
index 80bf243f0..6f9c0e3f5 100644
--- a/frontends/vhdl2verilog/vhdl2verilog.cc
+++ b/frontends/vhdl2verilog/vhdl2verilog.cc
@@ -74,7 +74,7 @@ struct Vhdl2verilogPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing VHDL2VERILOG (importing VHDL designs using vhdl2verilog).\n");
+		log_header(design, "Executing VHDL2VERILOG (importing VHDL designs using vhdl2verilog).\n");
 		log_push();
 
 		std::string out_file, top_entity;
@@ -173,7 +173,7 @@ struct Vhdl2verilogPass : public Pass {
 			Frontend::frontend_call(design, &ff, stringf("%s/vhdl2verilog_output.v", tempdir_name.c_str()), "verilog");
 		}
 
-		log_header("Removing temp directory `%s':\n", tempdir_name.c_str());
+		log_header(design, "Removing temp directory `%s':\n", tempdir_name.c_str());
 		remove_directory(tempdir_name);
 		log_pop();
 	}
diff --git a/kernel/driver.cc b/kernel/driver.cc
index a41d0e8cb..0844eaa2e 100644
--- a/kernel/driver.cc
+++ b/kernel/driver.cc
@@ -213,6 +213,10 @@ int main(int argc, char **argv)
 		printf("    -A\n");
 		printf("        will call abort() at the end of the script. for debugging\n");
 		printf("\n");
+		printf("    -D <header_id>[:<filename>]\n");
+		printf("        dump the design when printing the specified log header to a file.\n");
+		printf("        yosys_dump_<header_id>.il is used as filename if none is specified.\n");
+		printf("\n");
 		printf("    -V\n");
 		printf("        print version information and exit\n");
 		printf("\n");
@@ -233,7 +237,7 @@ int main(int argc, char **argv)
 	}
 
 	int opt;
-	while ((opt = getopt(argc, argv, "MXAQTVSm:f:Hh:b:o:p:l:L:qv:tds:c:")) != -1)
+	while ((opt = getopt(argc, argv, "MXAQTVSm:f:Hh:b:o:p:l:L:qv:tds:c:D:")) != -1)
 	{
 		switch (opt)
 		{
@@ -315,6 +319,18 @@ int main(int argc, char **argv)
 			scriptfile = optarg;
 			scriptfile_tcl = true;
 			break;
+		case 'D':
+			{
+				auto args = split_tokens(optarg, ":");
+				if (GetSize(args) == 1)
+					args.push_back("yosys_dump_" + args[0] + ".il");
+				if (GetSize(args) != 2) {
+					fprintf(stderr, "Invalid number of tokens in -D.\n");
+					exit(1);
+				}
+				log_hdump[args[0]].insert(args[1]);
+			}
+			break;
 		default:
 			fprintf(stderr, "Run '%s -h' for help.\n", argv[0]);
 			exit(1);
diff --git a/kernel/log.cc b/kernel/log.cc
index 4f395c751..f2b343dff 100644
--- a/kernel/log.cc
+++ b/kernel/log.cc
@@ -40,6 +40,7 @@ YOSYS_NAMESPACE_BEGIN
 
 std::vector<FILE*> log_files;
 std::vector<std::ostream*> log_streams;
+std::map<std::string, std::set<std::string>> log_hdump;
 FILE *log_errfile = NULL;
 SHA1 *log_hasher = NULL;
 
@@ -136,7 +137,7 @@ void logv(const char *format, va_list ap)
 		*f << str;
 }
 
-void logv_header(const char *format, va_list ap)
+void logv_header(RTLIL::Design *design, const char *format, va_list ap)
 {
 	bool pop_errfile = false;
 
@@ -149,12 +150,21 @@ void logv_header(const char *format, va_list ap)
 		pop_errfile = true;
 	}
 
+	std::string header_id;
+
 	for (int c : header_count)
-		log("%d.", c);
-	log(" ");
+		header_id += stringf("%s%d", header_id.empty() ? "" : ".", c);
+
+	log("%s. ", header_id.c_str());
 	logv(format, ap);
 	log_flush();
 
+	if (log_hdump.count(header_id) && design != nullptr)
+		for (auto &filename : log_hdump.at(header_id)) {
+			log("Dumping current design to '%s'.\n", filename.c_str());
+			Pass::call(design, {"dump", "-o", filename});
+		}
+
 	if (pop_errfile)
 		log_files.pop_back();
 }
@@ -206,11 +216,11 @@ void log(const char *format, ...)
 	va_end(ap);
 }
 
-void log_header(const char *format, ...)
+void log_header(RTLIL::Design *design, const char *format, ...)
 {
 	va_list ap;
 	va_start(ap, format);
-	logv_header(format, ap);
+	logv_header(design, format, ap);
 	va_end(ap);
 }
 
diff --git a/kernel/log.h b/kernel/log.h
index c0be23b08..6090f8273 100644
--- a/kernel/log.h
+++ b/kernel/log.h
@@ -47,6 +47,7 @@ struct log_cmd_error_exception { };
 
 extern std::vector<FILE*> log_files;
 extern std::vector<std::ostream*> log_streams;
+extern std::map<std::string, std::set<std::string>> log_hdump;
 extern FILE *log_errfile;
 extern SHA1 *log_hasher;
 
@@ -58,12 +59,12 @@ extern int log_verbose_level;
 extern string log_last_error;
 
 void logv(const char *format, va_list ap);
-void logv_header(const char *format, va_list ap);
+void logv_header(RTLIL::Design *design, const char *format, va_list ap);
 void logv_warning(const char *format, va_list ap);
 YS_NORETURN void logv_error(const char *format, va_list ap) YS_ATTRIBUTE(noreturn);
 
 void log(const char *format, ...)  YS_ATTRIBUTE(format(printf, 1, 2));
-void log_header(const char *format, ...) YS_ATTRIBUTE(format(printf, 1, 2));
+void log_header(RTLIL::Design *design, const char *format, ...) YS_ATTRIBUTE(format(printf, 2, 3));
 void log_warning(const char *format, ...) YS_ATTRIBUTE(format(printf, 1, 2));
 YS_NORETURN void log_error(const char *format, ...) YS_ATTRIBUTE(format(printf, 1, 2), noreturn);
 YS_NORETURN void log_cmd_error(const char *format, ...) YS_ATTRIBUTE(format(printf, 1, 2), noreturn);
diff --git a/kernel/register.cc b/kernel/register.cc
index ebe3055ac..115880ed6 100644
--- a/kernel/register.cc
+++ b/kernel/register.cc
@@ -165,7 +165,7 @@ void Pass::call(RTLIL::Design *design, std::string command)
 		while (!cmd_buf.empty() && (cmd_buf.back() == ' ' || cmd_buf.back() == '\t' ||
 				cmd_buf.back() == '\r' || cmd_buf.back() == '\n'))
 			cmd_buf.resize(cmd_buf.size()-1);
-		log_header("Shell command: %s\n", cmd_buf.c_str());
+		log_header(design, "Shell command: %s\n", cmd_buf.c_str());
 		int retCode = run_command(cmd_buf);
 		if (retCode != 0)
 			log_cmd_error("Shell command returned error code %d.\n", retCode);
diff --git a/manual/CHAPTER_Prog/stubnets.cc b/manual/CHAPTER_Prog/stubnets.cc
index 976107fbf..eb77bd404 100644
--- a/manual/CHAPTER_Prog/stubnets.cc
+++ b/manual/CHAPTER_Prog/stubnets.cc
@@ -103,7 +103,7 @@ struct StubnetsPass : public Pass {
 		// variables to mirror information from passed options
 		bool report_bits = 0;
 
-		log_header("Executing STUBNETS pass (find stub nets).\n");
+		log_header(design, "Executing STUBNETS pass (find stub nets).\n");
 
 		// parse options
 		size_t argidx;
diff --git a/manual/PRESENTATION_Prog.tex b/manual/PRESENTATION_Prog.tex
index 6b105a701..73c2bf419 100644
--- a/manual/PRESENTATION_Prog.tex
+++ b/manual/PRESENTATION_Prog.tex
@@ -477,7 +477,7 @@ log("Name of this module: %s\n", log_id(module->name));
 \medskip
 Use {\tt log\_header()} and {\tt log\_push()}/{\tt log\_pop()} to structure log messages:
 \begin{lstlisting}[xleftmargin=1cm, basicstyle=\ttfamily\fontsize{8pt}{10pt}\selectfont, language=C++]
-log_header("Doing important stuff!\n");
+log_header(design, "Doing important stuff!\n");
 log_push();
 for (int i = 0; i < 10; i++)
     log("Log message #%d.\n", i);
diff --git a/manual/PRESENTATION_Prog/my_cmd.cc b/manual/PRESENTATION_Prog/my_cmd.cc
index 1d28ce974..d99bfe1e8 100644
--- a/manual/PRESENTATION_Prog/my_cmd.cc
+++ b/manual/PRESENTATION_Prog/my_cmd.cc
@@ -65,7 +65,7 @@ struct Test2Pass : public Pass {
 
         log("Mapped signal x: %s\n", log_signal(sigmap(x)));
 
-        log_header("Doing important stuff!\n");
+        log_header(design, "Doing important stuff!\n");
         log_push();
         for (int i = 0; i < 10; i++)
             log("Log message #%d.\n", i);
diff --git a/passes/cmds/check.cc b/passes/cmds/check.cc
index 2ad848386..b3622cb19 100644
--- a/passes/cmds/check.cc
+++ b/passes/cmds/check.cc
@@ -68,7 +68,7 @@ struct CheckPass : public Pass {
 		}
 		extra_args(args, argidx, design);
 
-		log_header("Executing CHECK pass (checking for obvious problems).\n");
+		log_header(design, "Executing CHECK pass (checking for obvious problems).\n");
 
 		for (auto module : design->selected_whole_modules_warn())
 		{
diff --git a/passes/cmds/connwrappers.cc b/passes/cmds/connwrappers.cc
index 7828dce1d..c9ab226d5 100644
--- a/passes/cmds/connwrappers.cc
+++ b/passes/cmds/connwrappers.cc
@@ -198,7 +198,7 @@ struct ConnwrappersPass : public Pass {
 		}
 		extra_args(args, argidx, design);
 
-		log_header("Executing CONNWRAPPERS pass (connect extended ports of wrapper cells).\n");
+		log_header(design, "Executing CONNWRAPPERS pass (connect extended ports of wrapper cells).\n");
 
 		for (auto &mod_it : design->modules_)
 			if (design->selected(mod_it.second))
diff --git a/passes/cmds/cover.cc b/passes/cmds/cover.cc
index 5644066af..1475475c3 100644
--- a/passes/cmds/cover.cc
+++ b/passes/cmds/cover.cc
@@ -124,7 +124,7 @@ struct CoverPass : public Pass {
 		extra_args(args, argidx, design);
 
 		if (do_log) {
-			log_header("Printing code coverage counters.\n");
+			log_header(design, "Printing code coverage counters.\n");
 			log("\n");
 		}
 
diff --git a/passes/cmds/qwp.cc b/passes/cmds/qwp.cc
index 8ec815a72..8deb262b2 100644
--- a/passes/cmds/qwp.cc
+++ b/passes/cmds/qwp.cc
@@ -787,7 +787,7 @@ struct QwpPass : public Pass {
 		QwpConfig config;
 		xorshift32_state = 123456789;
 
-		log_header("Executing QWP pass (quadratic wirelength placer).\n");
+		log_header(design, "Executing QWP pass (quadratic wirelength placer).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/cmds/scc.cc b/passes/cmds/scc.cc
index 532026f26..007172406 100644
--- a/passes/cmds/scc.cc
+++ b/passes/cmds/scc.cc
@@ -264,7 +264,7 @@ struct SccPass : public Pass {
 		int maxDepth = -1;
 		int expect = -1;
 
-		log_header("Executing SCC pass (detecting logic loops).\n");
+		log_header(design, "Executing SCC pass (detecting logic loops).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/cmds/show.cc b/passes/cmds/show.cc
index 3b03d6802..87504a33f 100644
--- a/passes/cmds/show.cc
+++ b/passes/cmds/show.cc
@@ -651,7 +651,7 @@ struct ShowPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Generating Graphviz representation of design.\n");
+		log_header(design, "Generating Graphviz representation of design.\n");
 		log_push();
 
 		std::vector<std::pair<std::string, RTLIL::Selection>> color_selections;
@@ -784,7 +784,7 @@ struct ShowPass : public Pass {
 		}
 
 		if (libs.size() > 0)
-			log_header("Continuing show pass.\n");
+			log_header(design, "Continuing show pass.\n");
 
 		std::string dot_file = stringf("%s.dot", prefix.c_str());
 		std::string out_file = stringf("%s.%s", prefix.c_str(), format.empty() ? "svg" : format.c_str());
diff --git a/passes/cmds/splice.cc b/passes/cmds/splice.cc
index 2556fb740..7418ec4d2 100644
--- a/passes/cmds/splice.cc
+++ b/passes/cmds/splice.cc
@@ -341,7 +341,7 @@ struct SplicePass : public Pass {
 		if (!ports.empty() && !no_ports.empty())
 			log_cmd_error("The options -port and -no_port are exclusive!\n");
 
-		log_header("Executing SPLICE pass (creating cells for signal splicing).\n");
+		log_header(design, "Executing SPLICE pass (creating cells for signal splicing).\n");
 
 		for (auto &mod_it : design->modules_)
 		{
diff --git a/passes/cmds/splitnets.cc b/passes/cmds/splitnets.cc
index 0d7892d71..14eeb066f 100644
--- a/passes/cmds/splitnets.cc
+++ b/passes/cmds/splitnets.cc
@@ -109,7 +109,7 @@ struct SplitnetsPass : public Pass {
 		bool flag_driver = false;
 		std::string format = "[]:";
 
-		log_header("Executing SPLITNETS pass (splitting up multi-bit signals).\n");
+		log_header(design, "Executing SPLITNETS pass (splitting up multi-bit signals).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/passes/cmds/stat.cc b/passes/cmds/stat.cc
index 048933fcd..362a0edfc 100644
--- a/passes/cmds/stat.cc
+++ b/passes/cmds/stat.cc
@@ -232,7 +232,7 @@ struct StatPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Printing statistics.\n");
+		log_header(design, "Printing statistics.\n");
 
 		bool width_mode = false;
 		RTLIL::Module *top_mod = NULL;
diff --git a/passes/cmds/torder.cc b/passes/cmds/torder.cc
index 50317c023..56223610d 100644
--- a/passes/cmds/torder.cc
+++ b/passes/cmds/torder.cc
@@ -48,7 +48,7 @@ struct TorderPass : public Pass {
 		bool noautostop = false;
 		dict<IdString, pool<IdString>> stop_db;
 
-		log_header("Executing TORDER pass (print cells in topological order).\n");
+		log_header(design, "Executing TORDER pass (print cells in topological order).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/equiv/equiv_induct.cc b/passes/equiv/equiv_induct.cc
index cdb951ec9..c958c3de4 100644
--- a/passes/equiv/equiv_induct.cc
+++ b/passes/equiv/equiv_induct.cc
@@ -198,7 +198,7 @@ struct EquivInductPass : public Pass {
 		bool model_undef = false;
 		int max_seq = 4;
 
-		log_header("Executing EQUIV_INDUCT pass.\n");
+		log_header(design, "Executing EQUIV_INDUCT pass.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/equiv/equiv_make.cc b/passes/equiv/equiv_make.cc
index 8b063c542..40ca42621 100644
--- a/passes/equiv/equiv_make.cc
+++ b/passes/equiv/equiv_make.cc
@@ -464,7 +464,7 @@ struct EquivMakePass : public Pass {
 		worker.read_blacklists();
 		worker.read_encfiles();
 
-		log_header("Executing EQUIV_MAKE pass (creating equiv checking module).\n");
+		log_header(design, "Executing EQUIV_MAKE pass (creating equiv checking module).\n");
 
 		worker.equiv_mod = design->addModule(RTLIL::escape_id(args[argidx+2]));
 		worker.run();
diff --git a/passes/equiv/equiv_mark.cc b/passes/equiv/equiv_mark.cc
index 3e9819d1a..22c501763 100644
--- a/passes/equiv/equiv_mark.cc
+++ b/passes/equiv/equiv_mark.cc
@@ -218,7 +218,7 @@ struct EquivMarkPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, Design *design)
 	{
-		log_header("Executing EQUIV_MARK pass.\n");
+		log_header(design, "Executing EQUIV_MARK pass.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/equiv/equiv_miter.cc b/passes/equiv/equiv_miter.cc
index 982176c44..eb2e5a171 100644
--- a/passes/equiv/equiv_miter.cc
+++ b/passes/equiv/equiv_miter.cc
@@ -333,7 +333,7 @@ struct EquivMiterPass : public Pass {
 	found_two_modules:
 			log_cmd_error("Exactly one module must be selected for 'equiv_miter'!\n");
 
-		log_header("Executing EQUIV_MITER pass.\n");
+		log_header(design, "Executing EQUIV_MITER pass.\n");
 
 		worker.miter_module = design->addModule(worker.miter_name);
 		worker.run();
diff --git a/passes/equiv/equiv_purge.cc b/passes/equiv/equiv_purge.cc
index f4141ad4d..163b1009b 100644
--- a/passes/equiv/equiv_purge.cc
+++ b/passes/equiv/equiv_purge.cc
@@ -189,7 +189,7 @@ struct EquivPurgePass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, Design *design)
 	{
-		log_header("Executing EQUIV_PURGE pass.\n");
+		log_header(design, "Executing EQUIV_PURGE pass.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/equiv/equiv_remove.cc b/passes/equiv/equiv_remove.cc
index b5c383b64..770497a51 100644
--- a/passes/equiv/equiv_remove.cc
+++ b/passes/equiv/equiv_remove.cc
@@ -46,7 +46,7 @@ struct EquivRemovePass : public Pass {
 		bool mode_gate = false;
 		int remove_count = 0;
 
-		log_header("Executing EQUIV_REMOVE pass.\n");
+		log_header(design, "Executing EQUIV_REMOVE pass.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/equiv/equiv_simple.cc b/passes/equiv/equiv_simple.cc
index fa22dc621..49963ed68 100644
--- a/passes/equiv/equiv_simple.cc
+++ b/passes/equiv/equiv_simple.cc
@@ -277,7 +277,7 @@ struct EquivSimplePass : public Pass {
 		int success_counter = 0;
 		int max_seq = 1;
 
-		log_header("Executing EQUIV_SIMPLE pass.\n");
+		log_header(design, "Executing EQUIV_SIMPLE pass.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/equiv/equiv_status.cc b/passes/equiv/equiv_status.cc
index 8a2f5e05c..7b9230b35 100644
--- a/passes/equiv/equiv_status.cc
+++ b/passes/equiv/equiv_status.cc
@@ -41,7 +41,7 @@ struct EquivStatusPass : public Pass {
 		bool assert_mode = false;
 		int unproven_count = 0;
 
-		log_header("Executing EQUIV_STATUS pass.\n");
+		log_header(design, "Executing EQUIV_STATUS pass.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/equiv/equiv_struct.cc b/passes/equiv/equiv_struct.cc
index 2c85d2d3c..c4ced6a71 100644
--- a/passes/equiv/equiv_struct.cc
+++ b/passes/equiv/equiv_struct.cc
@@ -321,7 +321,7 @@ struct EquivStructPass : public Pass {
 		bool mode_fwd = false;
 		int max_iter = -1;
 
-		log_header("Executing EQUIV_STRUCT pass.\n");
+		log_header(design, "Executing EQUIV_STRUCT pass.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/fsm/fsm.cc b/passes/fsm/fsm.cc
index 3f5564fc5..3b537ecd8 100644
--- a/passes/fsm/fsm.cc
+++ b/passes/fsm/fsm.cc
@@ -76,7 +76,7 @@ struct FsmPass : public Pass {
 		std::string encfile_opt;
 		std::string encoding_opt;
 
-		log_header("Executing FSM pass (extract and optimize FSM).\n");
+		log_header(design, "Executing FSM pass (extract and optimize FSM).\n");
 		log_push();
 
 		size_t argidx;
diff --git a/passes/fsm/fsm_detect.cc b/passes/fsm/fsm_detect.cc
index 740113e35..5a240ba60 100644
--- a/passes/fsm/fsm_detect.cc
+++ b/passes/fsm/fsm_detect.cc
@@ -154,7 +154,7 @@ struct FsmDetectPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing FSM_DETECT pass (finding FSMs in design).\n");
+		log_header(design, "Executing FSM_DETECT pass (finding FSMs in design).\n");
 		extra_args(args, 1, design);
 
 		CellTypes ct;
diff --git a/passes/fsm/fsm_expand.cc b/passes/fsm/fsm_expand.cc
index 43c9a792f..3ded3f377 100644
--- a/passes/fsm/fsm_expand.cc
+++ b/passes/fsm/fsm_expand.cc
@@ -258,7 +258,7 @@ struct FsmExpandPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing FSM_EXPAND pass (merging auxiliary logic into FSMs).\n");
+		log_header(design, "Executing FSM_EXPAND pass (merging auxiliary logic into FSMs).\n");
 		extra_args(args, 1, design);
 
 		for (auto &mod_it : design->modules_) {
diff --git a/passes/fsm/fsm_export.cc b/passes/fsm/fsm_export.cc
index 0eff28844..1cbfcfae8 100644
--- a/passes/fsm/fsm_export.cc
+++ b/passes/fsm/fsm_export.cc
@@ -152,7 +152,7 @@ struct FsmExportPass : public Pass {
 		bool flag_origenc = false;
 		size_t argidx;
 
-		log_header("Executing FSM_EXPORT pass (exporting FSMs in KISS2 file format).\n");
+		log_header(design, "Executing FSM_EXPORT pass (exporting FSMs in KISS2 file format).\n");
 
 		for (argidx = 1; argidx < args.size(); argidx++) {
 			arg = args[argidx];
diff --git a/passes/fsm/fsm_extract.cc b/passes/fsm/fsm_extract.cc
index d61ac568d..95cb498e3 100644
--- a/passes/fsm/fsm_extract.cc
+++ b/passes/fsm/fsm_extract.cc
@@ -416,7 +416,7 @@ struct FsmExtractPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing FSM_EXTRACT pass (extracting FSM from design).\n");
+		log_header(design, "Executing FSM_EXTRACT pass (extracting FSM from design).\n");
 		extra_args(args, 1, design);
 
 		CellTypes ct;
diff --git a/passes/fsm/fsm_info.cc b/passes/fsm/fsm_info.cc
index 20db82c1f..2cc1a7d53 100644
--- a/passes/fsm/fsm_info.cc
+++ b/passes/fsm/fsm_info.cc
@@ -43,7 +43,7 @@ struct FsmInfoPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing FSM_INFO pass (dumping all available information on FSM cells).\n");
+		log_header(design, "Executing FSM_INFO pass (dumping all available information on FSM cells).\n");
 		extra_args(args, 1, design);
 
 		for (auto &mod_it : design->modules_)
diff --git a/passes/fsm/fsm_map.cc b/passes/fsm/fsm_map.cc
index 574b9a201..5b32ed599 100644
--- a/passes/fsm/fsm_map.cc
+++ b/passes/fsm/fsm_map.cc
@@ -335,7 +335,7 @@ struct FsmMapPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing FSM_MAP pass (mapping FSMs to basic logic).\n");
+		log_header(design, "Executing FSM_MAP pass (mapping FSMs to basic logic).\n");
 		extra_args(args, 1, design);
 
 		for (auto &mod_it : design->modules_) {
diff --git a/passes/fsm/fsm_opt.cc b/passes/fsm/fsm_opt.cc
index a7cc95ffa..5b1da44fc 100644
--- a/passes/fsm/fsm_opt.cc
+++ b/passes/fsm/fsm_opt.cc
@@ -336,7 +336,7 @@ struct FsmOptPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing FSM_OPT pass (simple optimizations of FSMs).\n");
+		log_header(design, "Executing FSM_OPT pass (simple optimizations of FSMs).\n");
 		extra_args(args, 1, design);
 
 		for (auto &mod_it : design->modules_) {
diff --git a/passes/fsm/fsm_recode.cc b/passes/fsm/fsm_recode.cc
index a4b45295e..5102d8334 100644
--- a/passes/fsm/fsm_recode.cc
+++ b/passes/fsm/fsm_recode.cc
@@ -157,7 +157,7 @@ struct FsmRecodePass : public Pass {
 		FILE *encfile = NULL;
 		std::string default_encoding;
 
-		log_header("Executing FSM_RECODE pass (re-assigning FSM state encoding).\n");
+		log_header(design, "Executing FSM_RECODE pass (re-assigning FSM state encoding).\n");
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
 			std::string arg = args[argidx];
diff --git a/passes/hierarchy/hierarchy.cc b/passes/hierarchy/hierarchy.cc
index 129f48399..460b3c693 100644
--- a/passes/hierarchy/hierarchy.cc
+++ b/passes/hierarchy/hierarchy.cc
@@ -396,7 +396,7 @@ struct HierarchyPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing HIERARCHY pass (managing design hierarchy).\n");
+		log_header(design, "Executing HIERARCHY pass (managing design hierarchy).\n");
 
 		bool flag_check = false;
 		bool purge_lib = false;
@@ -506,7 +506,7 @@ struct HierarchyPass : public Pass {
 					top_mod = mod_it.second;
 
 		if (top_mod == nullptr && auto_top_mode) {
-			log_header("Finding top of design hierarchy..\n");
+			log_header(design, "Finding top of design hierarchy..\n");
 			dict<Module*, int> db;
 			for (Module *mod : design->selected_modules()) {
 				int score = find_top_mod_score(design, mod, db);
@@ -525,7 +525,7 @@ struct HierarchyPass : public Pass {
 
 			std::set<RTLIL::Module*> used_modules;
 			if (top_mod != NULL) {
-				log_header("Analyzing design hierarchy..\n");
+				log_header(design, "Analyzing design hierarchy..\n");
 				hierarchy_worker(design, used_modules, top_mod, 0);
 			} else {
 				for (auto mod : design->modules())
@@ -539,7 +539,7 @@ struct HierarchyPass : public Pass {
 		}
 
 		if (top_mod != NULL) {
-			log_header("Analyzing design hierarchy..\n");
+			log_header(design, "Analyzing design hierarchy..\n");
 			hierarchy_clean(design, top_mod, purge_lib);
 		}
 
diff --git a/passes/hierarchy/singleton.cc b/passes/hierarchy/singleton.cc
index 5715c0eb1..03c365fb5 100644
--- a/passes/hierarchy/singleton.cc
+++ b/passes/hierarchy/singleton.cc
@@ -43,7 +43,7 @@ struct SingletonPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing SINGLETON pass (creating singleton modules).\n");
+		log_header(design, "Executing SINGLETON pass (creating singleton modules).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/passes/hierarchy/submod.cc b/passes/hierarchy/submod.cc
index d4e8c96ca..9f312f82d 100644
--- a/passes/hierarchy/submod.cc
+++ b/passes/hierarchy/submod.cc
@@ -298,7 +298,7 @@ struct SubmodPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing SUBMOD pass (moving cells to submodules as requested).\n");
+		log_header(design, "Executing SUBMOD pass (moving cells to submodules as requested).\n");
 		log_push();
 
 		std::string opt_name;
@@ -321,7 +321,7 @@ struct SubmodPass : public Pass {
 		if (opt_name.empty())
 		{
 			Pass::call(design, "opt_clean");
-			log_header("Continuing SUBMOD pass.\n");
+			log_header(design, "Continuing SUBMOD pass.\n");
 
 			std::set<RTLIL::IdString> handled_modules;
 
@@ -356,7 +356,7 @@ struct SubmodPass : public Pass {
 				log("Nothing selected -> do nothing.\n");
 			else {
 				Pass::call_on_module(design, module, "opt_clean");
-				log_header("Continuing SUBMOD pass.\n");
+				log_header(design, "Continuing SUBMOD pass.\n");
 				SubmodWorker worker(design, module, copy_mode, opt_name);
 			}
 		}
diff --git a/passes/memory/memory.cc b/passes/memory/memory.cc
index 4e74d1a48..e3c627607 100644
--- a/passes/memory/memory.cc
+++ b/passes/memory/memory.cc
@@ -53,7 +53,7 @@ struct MemoryPass : public Pass {
 		bool flag_nordff = false;
 		string memory_bram_opts;
 
-		log_header("Executing MEMORY pass.\n");
+		log_header(design, "Executing MEMORY pass.\n");
 		log_push();
 
 		size_t argidx;
diff --git a/passes/memory/memory_bram.cc b/passes/memory/memory_bram.cc
index f2d9b5847..cd424fd68 100644
--- a/passes/memory/memory_bram.cc
+++ b/passes/memory/memory_bram.cc
@@ -1211,7 +1211,7 @@ struct MemoryBramPass : public Pass {
 	{
 		rules_t rules;
 
-		log_header("Executing MEMORY_BRAM pass (mapping $mem cells to block memories).\n");
+		log_header(design, "Executing MEMORY_BRAM pass (mapping $mem cells to block memories).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/memory/memory_collect.cc b/passes/memory/memory_collect.cc
index 5c0acb3e5..e068ef905 100644
--- a/passes/memory/memory_collect.cc
+++ b/passes/memory/memory_collect.cc
@@ -247,7 +247,7 @@ struct MemoryCollectPass : public Pass {
 		log("\n");
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design) {
-		log_header("Executing MEMORY_COLLECT pass (generating $mem cells).\n");
+		log_header(design, "Executing MEMORY_COLLECT pass (generating $mem cells).\n");
 		extra_args(args, 1, design);
 		for (auto &mod_it : design->modules_)
 			if (design->selected(mod_it.second))
diff --git a/passes/memory/memory_dff.cc b/passes/memory/memory_dff.cc
index beb2016a9..40691d160 100644
--- a/passes/memory/memory_dff.cc
+++ b/passes/memory/memory_dff.cc
@@ -283,7 +283,7 @@ struct MemoryDffPass : public Pass {
 	{
 		bool flag_wr_only = false;
 
-		log_header("Executing MEMORY_DFF pass (merging $dff cells to $memrd and $memwr).\n");
+		log_header(design, "Executing MEMORY_DFF pass (merging $dff cells to $memrd and $memwr).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/memory/memory_map.cc b/passes/memory/memory_map.cc
index 0b8ccb363..bffeec857 100644
--- a/passes/memory/memory_map.cc
+++ b/passes/memory/memory_map.cc
@@ -363,7 +363,7 @@ struct MemoryMapPass : public Pass {
 		log("\n");
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design) {
-		log_header("Executing MEMORY_MAP pass (converting $mem cells to logic and flip-flops).\n");
+		log_header(design, "Executing MEMORY_MAP pass (converting $mem cells to logic and flip-flops).\n");
 		extra_args(args, 1, design);
 		for (auto mod : design->selected_modules())
 			MemoryMapWorker(design, mod);
diff --git a/passes/memory/memory_share.cc b/passes/memory/memory_share.cc
index ab9edb6e7..f298169de 100644
--- a/passes/memory/memory_share.cc
+++ b/passes/memory/memory_share.cc
@@ -43,7 +43,7 @@ struct MemoryShareWorker
 	CellTypes cone_ct;
 
 	std::map<RTLIL::SigBit, std::pair<RTLIL::Cell*, int>> sig_to_mux;
-	std::map<std::set<std::map<RTLIL::SigBit, bool>>, RTLIL::SigBit> conditions_logic_cache;
+	std::map<pair<std::set<std::map<SigBit, bool>>, SigBit>, SigBit> conditions_logic_cache;
 
 
 	// -----------------------------------------------------------------
@@ -109,10 +109,12 @@ struct MemoryShareWorker
 		return false;
 	}
 
-	RTLIL::SigBit conditions_to_logic(std::set<std::map<RTLIL::SigBit, bool>> &conditions, int &created_conditions)
+	RTLIL::SigBit conditions_to_logic(std::set<std::map<RTLIL::SigBit, bool>> &conditions, SigBit olden, int &created_conditions)
 	{
-		if (conditions_logic_cache.count(conditions))
-			return conditions_logic_cache.at(conditions);
+		auto key = make_pair(conditions, olden);
+
+		if (conditions_logic_cache.count(key))
+			return conditions_logic_cache.at(key);
 
 		RTLIL::SigSpec terms;
 		for (auto &cond : conditions) {
@@ -125,13 +127,16 @@ struct MemoryShareWorker
 			created_conditions++;
 		}
 
-		if (terms.size() == 0)
+		if (olden.wire != nullptr || olden != State::S1)
+			terms.append(olden);
+
+		if (GetSize(terms) == 0)
 			terms = State::S1;
 
-		if (terms.size() > 1)
+		if (GetSize(terms) > 1)
 			terms = module->ReduceAnd(NEW_ID, terms);
 
-		return conditions_logic_cache[conditions] = terms;
+		return conditions_logic_cache[key] = terms;
 	}
 
 	void translate_rd_feedback_to_en(std::string memid, std::vector<RTLIL::Cell*> &rd_ports, std::vector<RTLIL::Cell*> &wr_ports)
@@ -140,15 +145,14 @@ struct MemoryShareWorker
 		std::map<RTLIL::SigBit, std::set<RTLIL::SigBit>> muxtree_upstream_map;
 		std::set<RTLIL::SigBit> non_feedback_nets;
 
-		for (auto wire_it : module->wires_)
-			if (wire_it.second->port_output) {
-				std::vector<RTLIL::SigBit> bits = RTLIL::SigSpec(wire_it.second);
+		for (auto wire : module->wires())
+			if (wire->port_output) {
+				std::vector<RTLIL::SigBit> bits = sigmap(wire);
 				non_feedback_nets.insert(bits.begin(), bits.end());
 			}
 
-		for (auto cell_it : module->cells_)
+		for (auto cell : module->cells())
 		{
-			RTLIL::Cell *cell = cell_it.second;
 			bool ignore_data_port = false;
 
 			if (cell->type == "$mux" || cell->type == "$pmux")
@@ -173,7 +177,7 @@ struct MemoryShareWorker
 					cell->parameters.at("\\MEMID").decode_string() == memid)
 				ignore_data_port = true;
 
-			for (auto conn : cell_it.second->connections())
+			for (auto conn : cell->connections())
 			{
 				if (ignore_data_port && conn.first == "\\DATA")
 					continue;
@@ -240,13 +244,8 @@ struct MemoryShareWorker
 					std::map<RTLIL::SigBit, bool> state;
 					std::set<std::map<RTLIL::SigBit, bool>> conditions;
 
-					if (cell_en[i].wire != NULL) {
-						state[cell_en[i]] = false;
-						conditions.insert(state);
-					}
-
 					find_data_feedback(async_rd_bits.at(sig_addr).at(i), cell_data[i], state, conditions);
-					cell_en[i] = conditions_to_logic(conditions, created_conditions);
+					cell_en[i] = conditions_to_logic(conditions, cell_en[i], created_conditions);
 				}
 
 			if (created_conditions) {
@@ -666,10 +665,8 @@ struct MemoryShareWorker
 		std::map<std::string, std::pair<std::vector<RTLIL::Cell*>, std::vector<RTLIL::Cell*>>> memindex;
 
 		sigmap_xmux = sigmap;
-		for (auto &it : module->cells_)
+		for (auto cell : module->cells())
 		{
-			RTLIL::Cell *cell = it.second;
-
 			if (cell->type == "$memrd")
 				memindex[cell->parameters.at("\\MEMID").decode_string()].first.push_back(cell);
 
@@ -750,7 +747,7 @@ struct MemorySharePass : public Pass {
 		log("\n");
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design) {
-		log_header("Executing MEMORY_SHARE pass (consolidating $memrc/$memwr cells).\n");
+		log_header(design, "Executing MEMORY_SHARE pass (consolidating $memrc/$memwr cells).\n");
 		extra_args(args, 1, design);
 		for (auto module : design->selected_modules())
 			MemoryShareWorker(design, module);
diff --git a/passes/memory/memory_unpack.cc b/passes/memory/memory_unpack.cc
index 60724da77..a0fc31b5e 100644
--- a/passes/memory/memory_unpack.cc
+++ b/passes/memory/memory_unpack.cc
@@ -138,7 +138,7 @@ struct MemoryUnpackPass : public Pass {
 		log("\n");
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design) {
-		log_header("Executing MEMORY_UNPACK pass (generating $memrd/$memwr cells form $mem cells).\n");
+		log_header(design, "Executing MEMORY_UNPACK pass (generating $memrd/$memwr cells form $mem cells).\n");
 		extra_args(args, 1, design);
 		for (auto &mod_it : design->modules_)
 			if (design->selected(mod_it.second))
diff --git a/passes/opt/opt.cc b/passes/opt/opt.cc
index c25adac97..13ea5469b 100644
--- a/passes/opt/opt.cc
+++ b/passes/opt/opt.cc
@@ -71,7 +71,7 @@ struct OptPass : public Pass {
 		std::string opt_merge_args;
 		bool fast_mode = false;
 
-		log_header("Executing OPT pass (performing simple optimizations).\n");
+		log_header(design, "Executing OPT pass (performing simple optimizations).\n");
 		log_push();
 
 		size_t argidx;
@@ -132,7 +132,7 @@ struct OptPass : public Pass {
 				if (design->scratchpad_get_bool("opt.did_something") == false)
 					break;
 				Pass::call(design, "opt_clean" + opt_clean_args);
-				log_header("Rerunning OPT passes. (Removed registers in this run.)\n");
+				log_header(design, "Rerunning OPT passes. (Removed registers in this run.)\n");
 			}
 			Pass::call(design, "opt_clean" + opt_clean_args);
 		}
@@ -150,7 +150,7 @@ struct OptPass : public Pass {
 				Pass::call(design, "opt_expr" + opt_expr_args);
 				if (design->scratchpad_get_bool("opt.did_something") == false)
 					break;
-				log_header("Rerunning OPT passes. (Maybe there is more to do..)\n");
+				log_header(design, "Rerunning OPT passes. (Maybe there is more to do..)\n");
 			}
 		}
 
@@ -158,7 +158,7 @@ struct OptPass : public Pass {
 		design->sort();
 		design->check();
 
-		log_header(fast_mode ? "Finished fast OPT passes.\n" : "Finished OPT passes. (There is nothing left to do.)\n");
+		log_header(design, fast_mode ? "Finished fast OPT passes.\n" : "Finished OPT passes. (There is nothing left to do.)\n");
 		log_pop();
 	}
 } OptPass;
diff --git a/passes/opt/opt_clean.cc b/passes/opt/opt_clean.cc
index 175e8e112..466808216 100644
--- a/passes/opt/opt_clean.cc
+++ b/passes/opt/opt_clean.cc
@@ -380,7 +380,7 @@ struct OptCleanPass : public Pass {
 	{
 		bool purge_mode = false;
 
-		log_header("Executing OPT_CLEAN pass (remove unused cells and wires).\n");
+		log_header(design, "Executing OPT_CLEAN pass (remove unused cells and wires).\n");
 		log_push();
 
 		size_t argidx;
diff --git a/passes/opt/opt_expr.cc b/passes/opt/opt_expr.cc
index 9e713935d..a18ebb901 100644
--- a/passes/opt/opt_expr.cc
+++ b/passes/opt/opt_expr.cc
@@ -342,6 +342,68 @@ void replace_const_cells(RTLIL::Design *design, RTLIL::Module *module, bool cons
 			handle_clkpol_celltype_swap(cell, "$_DLATCHSR_??N_", "$_DLATCHSR_??P_", "\\R", assign_map, invert_map);
 		}
 
+		bool detect_const_and = false;
+		bool detect_const_or = false;
+
+		if (cell->type.in("$reduce_and", "$_AND_"))
+			detect_const_and = true;
+
+		if (cell->type.in("$and", "$logic_and") && GetSize(cell->getPort("\\A")) == 1 && GetSize(cell->getPort("\\B")) == 1)
+			detect_const_and = true;
+
+		if (cell->type.in("$reduce_or", "$reduce_bool", "$_OR_"))
+			detect_const_or = true;
+
+		if (cell->type.in("$or", "$logic_or") && GetSize(cell->getPort("\\A")) == 1 && GetSize(cell->getPort("\\B")) == 1)
+			detect_const_or = true;
+
+		if (detect_const_and || detect_const_or)
+		{
+			pool<SigBit> input_bits = assign_map(cell->getPort("\\A")).to_sigbit_pool();
+			bool found_zero = false, found_one = false, found_inv = false;
+
+			if (cell->hasPort("\\B")) {
+				vector<SigBit> more_bits = assign_map(cell->getPort("\\B")).to_sigbit_vector();
+				input_bits.insert(more_bits.begin(), more_bits.end());
+			}
+
+			for (auto bit : input_bits) {
+				if (bit == State::S0)
+					found_zero = true;
+				if (bit == State::S1)
+					found_one = true;
+				if (invert_map.count(bit) && input_bits.count(invert_map.at(bit)))
+					found_inv = true;
+			}
+
+			if (detect_const_and && (found_zero || found_inv)) {
+				cover("opt.opt_expr.const_and");
+				replace_cell(assign_map, module, cell, "const_and", "\\Y", RTLIL::State::S0);
+				goto next_cell;
+			}
+
+			if (detect_const_or && (found_one || found_inv)) {
+				cover("opt.opt_expr.const_or");
+				replace_cell(assign_map, module, cell, "const_or", "\\Y", RTLIL::State::S1);
+				goto next_cell;
+			}
+		}
+
+		if (cell->type.in("$reduce_and", "$reduce_or", "$reduce_bool", "$reduce_xor", "$reduce_xnor", "$neg") &&
+				GetSize(cell->getPort("\\A")) == 1 && GetSize(cell->getPort("\\Y")) == 1)
+		{
+			if (cell->type == "$reduce_xnor") {
+				cover("opt.opt_expr.reduce_xnor_not");
+				log("Replacing %s cell `%s' in module `%s' with $not cell.\n",
+						log_id(cell->type), log_id(cell->name), log_id(module));
+				cell->type = "$not";
+			} else {
+				cover("opt.opt_expr.unary_buffer");
+				replace_cell(assign_map, module, cell, "unary_buffer", "\\Y", cell->getPort("\\A"));
+			}
+			goto next_cell;
+		}
+
 		if (do_fine)
 		{
 			if (cell->type == "$not" || cell->type == "$pos" ||
@@ -428,18 +490,6 @@ void replace_const_cells(RTLIL::Design *design, RTLIL::Module *module, bool cons
 			}
 		}
 
-		if (cell->type == "$logic_or" && (assign_map(cell->getPort("\\A")) == RTLIL::State::S1 || assign_map(cell->getPort("\\B")) == RTLIL::State::S1)) {
-			cover("opt.opt_expr.one_high");
-			replace_cell(assign_map, module, cell, "one high", "\\Y", RTLIL::State::S1);
-			goto next_cell;
-		}
-
-		if (cell->type == "$logic_and" && (assign_map(cell->getPort("\\A")) == RTLIL::State::S0 || assign_map(cell->getPort("\\B")) == RTLIL::State::S0)) {
-			cover("opt.opt_expr.one_low");
-			replace_cell(assign_map, module, cell, "one low", "\\Y", RTLIL::State::S0);
-			goto next_cell;
-		}
-
 		if (cell->type == "$reduce_xor" || cell->type == "$reduce_xnor" || cell->type == "$shift" || cell->type == "$shiftx" ||
 				cell->type == "$shl" || cell->type == "$shr" || cell->type == "$sshl" || cell->type == "$sshr" ||
 				cell->type == "$lt" || cell->type == "$le" || cell->type == "$ge" || cell->type == "$gt" ||
@@ -1101,7 +1151,7 @@ struct OptExprPass : public Pass {
 		bool do_fine = false;
 		bool keepdc = false;
 
-		log_header("Executing OPT_EXPR pass (perform const folding).\n");
+		log_header(design, "Executing OPT_EXPR pass (perform const folding).\n");
 		log_push();
 
 		size_t argidx;
diff --git a/passes/opt/opt_merge.cc b/passes/opt/opt_merge.cc
index 07019aac9..97989d271 100644
--- a/passes/opt/opt_merge.cc
+++ b/passes/opt/opt_merge.cc
@@ -348,7 +348,7 @@ struct OptMergePass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing OPT_MERGE pass (detect identical cells).\n");
+		log_header(design, "Executing OPT_MERGE pass (detect identical cells).\n");
 
 		bool mode_nomux = false;
 		bool mode_share_all = false;
diff --git a/passes/opt/opt_muxtree.cc b/passes/opt/opt_muxtree.cc
index f9da807d2..f5ddc2af9 100644
--- a/passes/opt/opt_muxtree.cc
+++ b/passes/opt/opt_muxtree.cc
@@ -464,7 +464,7 @@ struct OptMuxtreePass : public Pass {
 	}
 	virtual void execute(vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing OPT_MUXTREE pass (detect dead branches in mux trees).\n");
+		log_header(design, "Executing OPT_MUXTREE pass (detect dead branches in mux trees).\n");
 		extra_args(args, 1, design);
 
 		int total_count = 0;
diff --git a/passes/opt/opt_reduce.cc b/passes/opt/opt_reduce.cc
index 98b7b2e15..eb9d02ad5 100644
--- a/passes/opt/opt_reduce.cc
+++ b/passes/opt/opt_reduce.cc
@@ -354,7 +354,7 @@ struct OptReducePass : public Pass {
 	{
 		bool do_fine = false;
 
-		log_header("Executing OPT_REDUCE pass (consolidate $*mux and $reduce_* inputs).\n");
+		log_header(design, "Executing OPT_REDUCE pass (consolidate $*mux and $reduce_* inputs).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/opt/opt_rmdff.cc b/passes/opt/opt_rmdff.cc
index e1b184af3..1711d0f45 100644
--- a/passes/opt/opt_rmdff.cc
+++ b/passes/opt/opt_rmdff.cc
@@ -191,7 +191,7 @@ struct OptRmdffPass : public Pass {
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
 		int total_count = 0;
-		log_header("Executing OPT_RMDFF pass (remove dff with constant values).\n");
+		log_header(design, "Executing OPT_RMDFF pass (remove dff with constant values).\n");
 
 		extra_args(args, 1, design);
 
diff --git a/passes/opt/share.cc b/passes/opt/share.cc
index 1d9b1006e..22914eaa7 100644
--- a/passes/opt/share.cc
+++ b/passes/opt/share.cc
@@ -793,10 +793,59 @@ struct ShareWorker
 		return true;
 	}
 
-	void optimize_activation_patterns(pool<ssc_pair_t> & /* patterns */)
+	void optimize_activation_patterns(pool<ssc_pair_t> &patterns)
 	{
 		// TODO: Remove patterns that are contained in other patterns
-		// TODO: Consolidate pairs of patterns that only differ in the value for one signal bit
+
+		dict<SigSpec, pool<Const>> db;
+		bool did_something = false;
+
+		for (auto const &p : patterns)
+		{
+			auto &sig = p.first;
+			auto &val = p.second;
+			int len = GetSize(sig);
+
+			for (int i = 0; i < len; i++)
+			{
+				auto otherval = val;
+
+				if (otherval.bits[i] == State::S0)
+					otherval.bits[i] = State::S1;
+				else if (otherval.bits[i] == State::S1)
+					otherval.bits[i] = State::S0;
+				else
+					continue;
+
+				if (db[sig].count(otherval))
+				{
+					auto newsig = sig;
+					newsig.remove(i);
+
+					auto newval = val;
+					newval.bits.erase(newval.bits.begin() + i);
+
+					db[newsig].insert(newval);
+					db[sig].erase(otherval);
+
+					did_something = true;
+					goto next_pattern;
+				}
+			}
+
+			db[sig].insert(val);
+		next_pattern:;
+		}
+
+		if (!did_something)
+			return;
+
+		patterns.clear();
+		for (auto &it : db)
+		for (auto &val : it.second)
+			patterns.insert(make_pair(it.first, val));
+
+		optimize_activation_patterns(patterns);
 	}
 
 	const pool<ssc_pair_t> &find_cell_activation_patterns(RTLIL::Cell *cell, const char *indent)
@@ -1451,7 +1500,7 @@ struct SharePass : public Pass {
 		config.generic_other_ops.insert("$alu");
 		config.generic_other_ops.insert("$macc");
 
-		log_header("Executing SHARE pass (SAT-based resource sharing).\n");
+		log_header(design, "Executing SHARE pass (SAT-based resource sharing).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/opt/wreduce.cc b/passes/opt/wreduce.cc
index 4f08da675..333541eab 100644
--- a/passes/opt/wreduce.cc
+++ b/passes/opt/wreduce.cc
@@ -371,7 +371,7 @@ struct WreducePass : public Pass {
 	{
 		WreduceConfig config;
 
-		log_header("Executing WREDUCE pass (reducing word size of cells).\n");
+		log_header(design, "Executing WREDUCE pass (reducing word size of cells).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/proc/proc.cc b/passes/proc/proc.cc
index 577ff6bf5..6998cef7e 100644
--- a/passes/proc/proc.cc
+++ b/passes/proc/proc.cc
@@ -57,7 +57,7 @@ struct ProcPass : public Pass {
 	{
 		std::string global_arst;
 
-		log_header("Executing PROC pass (convert processes to netlists).\n");
+		log_header(design, "Executing PROC pass (convert processes to netlists).\n");
 		log_push();
 
 		size_t argidx;
diff --git a/passes/proc/proc_arst.cc b/passes/proc/proc_arst.cc
index 1da237283..216b00ddd 100644
--- a/passes/proc/proc_arst.cc
+++ b/passes/proc/proc_arst.cc
@@ -226,7 +226,7 @@ struct ProcArstPass : public Pass {
 		std::string global_arst;
 		bool global_arst_neg = false;
 
-		log_header("Executing PROC_ARST pass (detect async resets in processes).\n");
+		log_header(design, "Executing PROC_ARST pass (detect async resets in processes).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/passes/proc/proc_clean.cc b/passes/proc/proc_clean.cc
index 35801951a..7dbabc211 100644
--- a/passes/proc/proc_clean.cc
+++ b/passes/proc/proc_clean.cc
@@ -156,7 +156,7 @@ struct ProcCleanPass : public Pass {
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
 		int total_count = 0;
-		log_header("Executing PROC_CLEAN pass (remove empty switches from decision trees).\n");
+		log_header(design, "Executing PROC_CLEAN pass (remove empty switches from decision trees).\n");
 
 		extra_args(args, 1, design);
 
diff --git a/passes/proc/proc_dff.cc b/passes/proc/proc_dff.cc
index 637131399..f532990c2 100644
--- a/passes/proc/proc_dff.cc
+++ b/passes/proc/proc_dff.cc
@@ -369,7 +369,7 @@ struct ProcDffPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing PROC_DFF pass (convert process syncs to FFs).\n");
+		log_header(design, "Executing PROC_DFF pass (convert process syncs to FFs).\n");
 
 		extra_args(args, 1, design);
 
diff --git a/passes/proc/proc_dlatch.cc b/passes/proc/proc_dlatch.cc
index e37d81ddd..c339ac682 100644
--- a/passes/proc/proc_dlatch.cc
+++ b/passes/proc/proc_dlatch.cc
@@ -292,7 +292,7 @@ struct ProcDlatchPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing PROC_DLATCH pass (convert process syncs to latches).\n");
+		log_header(design, "Executing PROC_DLATCH pass (convert process syncs to latches).\n");
 
 		extra_args(args, 1, design);
 
diff --git a/passes/proc/proc_init.cc b/passes/proc/proc_init.cc
index 633d4e58a..0c8fb83dc 100644
--- a/passes/proc/proc_init.cc
+++ b/passes/proc/proc_init.cc
@@ -61,13 +61,28 @@ void proc_init(RTLIL::Module *mod, RTLIL::Process *proc)
 					log_cmd_error("Failed to get a constant init value for %s: %s\n", log_signal(lhs), log_signal(rhs));
 
 				int offset = 0;
-				for (auto &lhs_c : lhs.chunks()) {
-					if (lhs_c.wire != NULL) {
-						RTLIL::SigSpec value = rhs.extract(offset, lhs_c.width);
-						if (value.size() != lhs_c.wire->width)
-							log_cmd_error("Init value is not for the entire wire: %s = %s\n", log_signal(lhs_c), log_signal(value));
-						log("  Setting init value: %s = %s\n", log_signal(lhs_c.wire), log_signal(value));
-						lhs_c.wire->attributes["\\init"] = value.as_const();
+				for (auto &lhs_c : lhs.chunks())
+				{
+					if (lhs_c.wire != nullptr)
+					{
+						SigSpec valuesig = rhs.extract(offset, lhs_c.width);
+						if (!valuesig.is_fully_const())
+							log_cmd_error("Non-const initialization value: %s = %s\n", log_signal(lhs_c), log_signal(valuesig));
+
+						Const value = valuesig.as_const();
+						Const &wireinit = lhs_c.wire->attributes["\\init"];
+
+						while (GetSize(wireinit.bits) < lhs_c.wire->width)
+							wireinit.bits.push_back(State::Sx);
+
+						for (int i = 0; i < lhs_c.width; i++) {
+							auto &initbit = wireinit.bits[i + lhs_c.offset];
+							if (initbit != State::Sx && initbit != value[i])
+								log_cmd_error("Conflicting initialization values for %s.\n", log_signal(lhs_c));
+							initbit = value[i];
+						}
+
+						log("  Set init value: %s = %s\n", log_signal(lhs_c.wire), log_signal(wireinit));
 					}
 					offset += lhs_c.width;
 				}
@@ -100,7 +115,7 @@ struct ProcInitPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing PROC_INIT pass (extract init attributes).\n");
+		log_header(design, "Executing PROC_INIT pass (extract init attributes).\n");
 
 		extra_args(args, 1, design);
 
diff --git a/passes/proc/proc_mux.cc b/passes/proc/proc_mux.cc
index 943e8c562..dcfa212b5 100644
--- a/passes/proc/proc_mux.cc
+++ b/passes/proc/proc_mux.cc
@@ -391,7 +391,7 @@ struct ProcMuxPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing PROC_MUX pass (convert decision trees to multiplexers).\n");
+		log_header(design, "Executing PROC_MUX pass (convert decision trees to multiplexers).\n");
 
 		extra_args(args, 1, design);
 
diff --git a/passes/proc/proc_rmdead.cc b/passes/proc/proc_rmdead.cc
index af17e8d38..5672fb475 100644
--- a/passes/proc/proc_rmdead.cc
+++ b/passes/proc/proc_rmdead.cc
@@ -76,7 +76,7 @@ struct ProcRmdeadPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing PROC_RMDEAD pass (remove dead branches from decision trees).\n");
+		log_header(design, "Executing PROC_RMDEAD pass (remove dead branches from decision trees).\n");
 
 		extra_args(args, 1, design);
 
diff --git a/passes/sat/eval.cc b/passes/sat/eval.cc
index 614a1bd31..09f69cc5c 100644
--- a/passes/sat/eval.cc
+++ b/passes/sat/eval.cc
@@ -389,7 +389,7 @@ struct EvalPass : public Pass {
 		std::vector<std::string> shows, tables;
 		bool set_undef = false;
 
-		log_header("Executing EVAL pass (evaluate the circuit given an input).\n");
+		log_header(design, "Executing EVAL pass (evaluate the circuit given an input).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/sat/expose.cc b/passes/sat/expose.cc
index ebdf2ed5d..9427547f3 100644
--- a/passes/sat/expose.cc
+++ b/passes/sat/expose.cc
@@ -262,7 +262,7 @@ struct ExposePass : public Pass {
 		bool flag_evert_dff = false;
 		std::string sep = ".";
 
-		log_header("Executing EXPOSE pass (exposing internal signals as outputs).\n");
+		log_header(design, "Executing EXPOSE pass (exposing internal signals as outputs).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/passes/sat/freduce.cc b/passes/sat/freduce.cc
index 373b80488..77263f6a2 100644
--- a/passes/sat/freduce.cc
+++ b/passes/sat/freduce.cc
@@ -798,7 +798,7 @@ struct FreducePass : public Pass {
 		inv_mode = false;
 		dump_prefix = std::string();
 
-		log_header("Executing FREDUCE pass (perform functional reduction).\n");
+		log_header(design, "Executing FREDUCE pass (perform functional reduction).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/sat/miter.cc b/passes/sat/miter.cc
index e809425c8..4854e19bf 100644
--- a/passes/sat/miter.cc
+++ b/passes/sat/miter.cc
@@ -32,7 +32,7 @@ void create_miter_equiv(struct Pass *that, std::vector<std::string> args, RTLIL:
 	bool flag_make_assert = false;
 	bool flag_flatten = false;
 
-	log_header("Executing MITER pass (creating miter circuit).\n");
+	log_header(design, "Executing MITER pass (creating miter circuit).\n");
 
 	size_t argidx;
 	for (argidx = 2; argidx < args.size(); argidx++)
@@ -264,7 +264,7 @@ void create_miter_assert(struct Pass *that, std::vector<std::string> args, RTLIL
 	bool flag_make_outputs = false;
 	bool flag_flatten = false;
 
-	log_header("Executing MITER pass (creating miter circuit).\n");
+	log_header(design, "Executing MITER pass (creating miter circuit).\n");
 
 	size_t argidx;
 	for (argidx = 2; argidx < args.size(); argidx++)
diff --git a/passes/sat/sat.cc b/passes/sat/sat.cc
index a91f657bc..c3cb435d1 100644
--- a/passes/sat/sat.cc
+++ b/passes/sat/sat.cc
@@ -1073,7 +1073,7 @@ struct SatPass : public Pass {
 		int tempinduct_skip = 0, stepsize = 1;
 		std::string vcd_file_name, json_file_name, cnf_file_name;
 
-		log_header("Executing SAT pass (solving SAT problems in the circuit).\n");
+		log_header(design, "Executing SAT pass (solving SAT problems in the circuit).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/techmap/abc.cc b/passes/techmap/abc.cc
index cddc23661..67fef32a2 100644
--- a/passes/techmap/abc.cc
+++ b/passes/techmap/abc.cc
@@ -616,7 +616,7 @@ void abc_module(RTLIL::Design *design, RTLIL::Module *current_module, std::strin
 	if (!cleanup)
 		tempdir_name[0] = tempdir_name[4] = '_';
 	tempdir_name = make_temp_dir(tempdir_name);
-	log_header("Extracting gate netlist of module `%s' to `%s/input.blif'..\n",
+	log_header(design, "Extracting gate netlist of module `%s' to `%s/input.blif'..\n",
 			module->name.c_str(), replace_tempdir(tempdir_name, tempdir_name, show_tempdir).c_str());
 
 	std::string abc_script = stringf("read_blif %s/input.blif; ", tempdir_name.c_str());
@@ -834,7 +834,7 @@ void abc_module(RTLIL::Design *design, RTLIL::Module *current_module, std::strin
 
 	if (count_output > 0)
 	{
-		log_header("Executing ABC.\n");
+		log_header(design, "Executing ABC.\n");
 
 		buffer = stringf("%s/stdcells.genlib", tempdir_name.c_str());
 		f = fopen(buffer.c_str(), "wt");
@@ -904,7 +904,7 @@ void abc_module(RTLIL::Design *design, RTLIL::Module *current_module, std::strin
 
 		ifs.close();
 
-		log_header("Re-integrating ABC results.\n");
+		log_header(design, "Re-integrating ABC results.\n");
 		RTLIL::Module *mapped_mod = mapped_design->modules_["\\netlist"];
 		if (mapped_mod == NULL)
 			log_error("ABC output file does not contain a module `netlist'.\n");
@@ -1299,7 +1299,7 @@ struct AbcPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing ABC pass (technology mapping using ABC).\n");
+		log_header(design, "Executing ABC pass (technology mapping using ABC).\n");
 		log_push();
 
 #ifdef ABCEXTERNAL
@@ -1599,7 +1599,7 @@ struct AbcPass : public Pass {
 					assigned_cells_reverse[cell] = key;
 				}
 
-				log_header("Summary of detected clock domains:\n");
+				log_header(design, "Summary of detected clock domains:\n");
 				for (auto &it : assigned_cells)
 					log("  %d cells in clk=%s%s, en=%s%s\n", GetSize(it.second),
 							std::get<0>(it.first) ? "" : "!", log_signal(std::get<1>(it.first)),
diff --git a/passes/techmap/aigmap.cc b/passes/techmap/aigmap.cc
index db1c731e9..b9ac7aded 100644
--- a/passes/techmap/aigmap.cc
+++ b/passes/techmap/aigmap.cc
@@ -41,7 +41,7 @@ struct AigmapPass : public Pass {
 	{
 		bool nand_mode = false;
 
-		log_header("Executing AIGMAP pass (map logic to AIG).\n");
+		log_header(design, "Executing AIGMAP pass (map logic to AIG).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/passes/techmap/alumacc.cc b/passes/techmap/alumacc.cc
index 3c7ff4b92..9f6dd02d0 100644
--- a/passes/techmap/alumacc.cc
+++ b/passes/techmap/alumacc.cc
@@ -544,7 +544,7 @@ struct AlumaccPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing ALUMACC pass (create $alu and $macc cells).\n");
+		log_header(design, "Executing ALUMACC pass (create $alu and $macc cells).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/techmap/dff2dffe.cc b/passes/techmap/dff2dffe.cc
index 51bfaade3..1b8920bb7 100644
--- a/passes/techmap/dff2dffe.cc
+++ b/passes/techmap/dff2dffe.cc
@@ -285,7 +285,7 @@ struct Dff2dffePass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing DFF2DFFE pass (transform $dff to $dffe where applicable).\n");
+		log_header(design, "Executing DFF2DFFE pass (transform $dff to $dffe where applicable).\n");
 
 		bool unmap_mode = false;
 		dict<IdString, IdString> direct_dict;
diff --git a/passes/techmap/dffinit.cc b/passes/techmap/dffinit.cc
index e0273f439..d737b3424 100644
--- a/passes/techmap/dffinit.cc
+++ b/passes/techmap/dffinit.cc
@@ -41,7 +41,7 @@ struct DffinitPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing DFFINIT pass (set INIT param on FF cells).\n");
+		log_header(design, "Executing DFFINIT pass (set INIT param on FF cells).\n");
 
 		dict<IdString, dict<IdString, IdString>> ff_types;
 
diff --git a/passes/techmap/dfflibmap.cc b/passes/techmap/dfflibmap.cc
index 3195e5a78..c8104fb7e 100644
--- a/passes/techmap/dfflibmap.cc
+++ b/passes/techmap/dfflibmap.cc
@@ -547,7 +547,7 @@ struct DfflibmapPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing DFFLIBMAP pass (mapping DFF cells to sequential cells from liberty file).\n");
+		log_header(design, "Executing DFFLIBMAP pass (mapping DFF cells to sequential cells from liberty file).\n");
 
 		std::string liberty_file;
 		bool prepare_mode = false;
diff --git a/passes/techmap/dffsr2dff.cc b/passes/techmap/dffsr2dff.cc
index 8dcbb4ed2..0d4d53627 100644
--- a/passes/techmap/dffsr2dff.cc
+++ b/passes/techmap/dffsr2dff.cc
@@ -188,7 +188,7 @@ struct Dffsr2dffPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing DFFSR2DFF pass (mapping DFFSR cells to simpler FFs).\n");
+		log_header(design, "Executing DFFSR2DFF pass (mapping DFFSR cells to simpler FFs).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/passes/techmap/extract.cc b/passes/techmap/extract.cc
index fc73177ce..71e29c60b 100644
--- a/passes/techmap/extract.cc
+++ b/passes/techmap/extract.cc
@@ -442,7 +442,7 @@ struct ExtractPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing EXTRACT pass (map subcircuits to cells).\n");
+		log_header(design, "Executing EXTRACT pass (map subcircuits to cells).\n");
 		log_push();
 
 		SubCircuitSolver solver;
@@ -627,7 +627,7 @@ struct ExtractPass : public Pass {
 		std::map<std::string, RTLIL::Module*> needle_map, haystack_map;
 		std::vector<RTLIL::Module*> needle_list;
 
-		log_header("Creating graphs for SubCircuit library.\n");
+		log_header(design, "Creating graphs for SubCircuit library.\n");
 
 		if (!mine_mode)
 			for (auto &mod_it : map->modules_) {
@@ -654,7 +654,7 @@ struct ExtractPass : public Pass {
 		if (!mine_mode)
 		{
 			std::vector<SubCircuit::Solver::Result> results;
-			log_header("Running solver from SubCircuit library.\n");
+			log_header(design, "Running solver from SubCircuit library.\n");
 
 			std::sort(needle_list.begin(), needle_list.end(), compareSortNeedleList);
 
@@ -667,7 +667,7 @@ struct ExtractPass : public Pass {
 
 			if (results.size() > 0)
 			{
-				log_header("Substitute SubCircuits with cells.\n");
+				log_header(design, "Substitute SubCircuits with cells.\n");
 
 				for (int i = 0; i < int(results.size()); i++) {
 					auto &result = results[i];
@@ -688,7 +688,7 @@ struct ExtractPass : public Pass {
 		{
 			std::vector<SubCircuit::Solver::MineResult> results;
 
-			log_header("Running miner from SubCircuit library.\n");
+			log_header(design, "Running miner from SubCircuit library.\n");
 			solver.mine(results, mine_cells_min, mine_cells_max, mine_min_freq, mine_limit_mod);
 
 			map = new RTLIL::Design;
diff --git a/passes/techmap/hilomap.cc b/passes/techmap/hilomap.cc
index a0bd2f9ae..82cecac26 100644
--- a/passes/techmap/hilomap.cc
+++ b/passes/techmap/hilomap.cc
@@ -76,7 +76,7 @@ struct HilomapPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing HILOMAP pass (mapping to constant drivers).\n");
+		log_header(design, "Executing HILOMAP pass (mapping to constant drivers).\n");
 
 		hicell_celltype = std::string();
 		hicell_portname = std::string();
diff --git a/passes/techmap/iopadmap.cc b/passes/techmap/iopadmap.cc
index 9dab40ca8..a28121052 100644
--- a/passes/techmap/iopadmap.cc
+++ b/passes/techmap/iopadmap.cc
@@ -68,7 +68,7 @@ struct IopadmapPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing IOPADMAP pass (mapping inputs/outputs to IO-PAD cells).\n");
+		log_header(design, "Executing IOPADMAP pass (mapping inputs/outputs to IO-PAD cells).\n");
 
 		std::string inpad_celltype, inpad_portname, inpad_portname2;
 		std::string outpad_celltype, outpad_portname, outpad_portname2;
diff --git a/passes/techmap/lut2mux.cc b/passes/techmap/lut2mux.cc
index b2c4f31a8..2bb0bd8b4 100644
--- a/passes/techmap/lut2mux.cc
+++ b/passes/techmap/lut2mux.cc
@@ -67,7 +67,7 @@ struct Lut2muxPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing LUT2MUX pass (convert $lut to $_MUX_).\n");
+		log_header(design, "Executing LUT2MUX pass (convert $lut to $_MUX_).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/passes/techmap/maccmap.cc b/passes/techmap/maccmap.cc
index d5b8fe804..32569d076 100644
--- a/passes/techmap/maccmap.cc
+++ b/passes/techmap/maccmap.cc
@@ -379,7 +379,7 @@ struct MaccmapPass : public Pass {
 	{
 		bool unmap_mode = false;
 
-		log_header("Executing MACCMAP pass (map $macc cells).\n");
+		log_header(design, "Executing MACCMAP pass (map $macc cells).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/techmap/muxcover.cc b/passes/techmap/muxcover.cc
index 514c3365f..1dc649587 100644
--- a/passes/techmap/muxcover.cc
+++ b/passes/techmap/muxcover.cc
@@ -581,7 +581,7 @@ struct MuxcoverPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing MUXCOVER pass (mapping to wider MUXes).\n");
+		log_header(design, "Executing MUXCOVER pass (mapping to wider MUXes).\n");
 
 		bool use_mux4 = false;
 		bool use_mux8 = false;
diff --git a/passes/techmap/nlutmap.cc b/passes/techmap/nlutmap.cc
index f5e77722e..a6d4e1a2f 100644
--- a/passes/techmap/nlutmap.cc
+++ b/passes/techmap/nlutmap.cc
@@ -143,7 +143,7 @@ struct NlutmapPass : public Pass {
 	{
 		NlutmapConfig config;
 
-		log_header("Executing NLUTMAP pass (mapping to constant drivers).\n");
+		log_header(design, "Executing NLUTMAP pass (mapping to constant drivers).\n");
 		log_push();
 
 		size_t argidx;
diff --git a/passes/techmap/pmuxtree.cc b/passes/techmap/pmuxtree.cc
index 3c12bfd02..c626dbcc5 100644
--- a/passes/techmap/pmuxtree.cc
+++ b/passes/techmap/pmuxtree.cc
@@ -78,7 +78,7 @@ struct PmuxtreePass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing PMUXTREE pass.\n");
+		log_header(design, "Executing PMUXTREE pass.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/techmap/shregmap.cc b/passes/techmap/shregmap.cc
index cd7afec12..c8f69b389 100644
--- a/passes/techmap/shregmap.cc
+++ b/passes/techmap/shregmap.cc
@@ -23,12 +23,20 @@
 USING_YOSYS_NAMESPACE
 PRIVATE_NAMESPACE_BEGIN
 
+struct ShregmapTech
+{
+	virtual ~ShregmapTech() { }
+	virtual bool check_taps(const dict<int, SigBit> &taps) = 0;
+	virtual bool fixup_shreg(Cell *cell, dict<int, SigBit> &taps) = 0;
+};
+
 struct ShregmapOptions
 {
 	int minlen, maxlen;
 	int keep_before, keep_after;
 	bool zinit, init, params, ffe;
 	dict<IdString, pair<IdString, IdString>> ffcells;
+	ShregmapTech *tech;
 
 	ShregmapOptions()
 	{
@@ -40,6 +48,42 @@ struct ShregmapOptions
 		init = false;
 		params = false;
 		ffe = false;
+		tech = nullptr;
+	}
+};
+
+struct ShregmapTechGreenpak4 : ShregmapTech
+{
+	bool check_taps(const dict<int, SigBit> &taps)
+	{
+		if (GetSize(taps) > 2)
+			return false;
+
+		for (auto tap : taps)
+			if (tap.first > 16) return false;
+
+		return true;
+	}
+
+	bool fixup_shreg(Cell *cell, dict<int, SigBit> &taps)
+	{
+		auto D = cell->getPort("\\D");
+		auto C = cell->getPort("\\C");
+
+		auto newcell = cell->module->addCell(NEW_ID, "\\GP_SHREG");
+		newcell->setPort("\\nRST", State::S1);
+		newcell->setPort("\\CLK", C);
+		newcell->setPort("\\IN", D);
+
+		int i = 0;
+		for (auto tap : taps) {
+			newcell->setPort(i ? "\\OUTB" : "\\OUTA", tap.second);
+			newcell->setParam(i ? "\\OUTB_DELAY" : "\\OUTA_DELAY", tap.first + 1);
+			i++;
+		}
+
+		cell->setParam("\\OUTA_INVERT", 0);
+		return false;
 	}
 };
 
@@ -90,7 +134,8 @@ struct ShregmapWorker
 				SigBit d_bit = sigmap(cell->getPort(d_port).as_bit());
 				SigBit q_bit = sigmap(cell->getPort(q_port).as_bit());
 
-				if (opts.init || sigbit_init.count(q_bit) == 0) {
+				if (opts.init || sigbit_init.count(q_bit) == 0)
+				{
 					if (sigbit_chain_next.count(d_bit)) {
 						sigbit_with_non_chain_users.insert(d_bit);
 					} else
@@ -112,8 +157,8 @@ struct ShregmapWorker
 	{
 		for (auto it : sigbit_chain_next)
 		{
-			if (sigbit_with_non_chain_users.count(it.first))
-				continue;
+			if (opts.tech == nullptr && sigbit_with_non_chain_users.count(it.first))
+				goto start_cell;
 
 			if (sigbit_chain_prev.count(it.first) != 0)
 			{
@@ -185,11 +230,36 @@ struct ShregmapWorker
 			if (opts.maxlen > 0)
 				depth = std::min(opts.maxlen, depth);
 
-			Cell *first_cell = chain[cursor], *last_cell = chain[cursor+depth-1];
+			Cell *first_cell = chain[cursor];
+			IdString q_port = opts.ffcells.at(first_cell->type).second;
+			dict<int, SigBit> taps;
+
+			if (opts.tech)
+			{
+				for (int i = 0; i < depth; i++)
+				{
+					Cell *cell = chain[cursor+i];
+					auto qbit = sigmap(cell->getPort(q_port));
+
+					if (sigbit_with_non_chain_users.count(qbit))
+						taps[i] = qbit;
+				}
+
+				while (depth > 0)
+				{
+					Cell *last_cell = chain[cursor+depth-1];
+					taps[depth-1] = sigmap(last_cell->getPort(q_port));
+					if (opts.tech->check_taps(taps))
+						break;
+					taps.erase(--depth);
+				}
+			}
 
 			if (depth < 2)
 				return;
 
+			Cell *last_cell = chain[cursor+depth-1];
+
 			log("Converting %s.%s ... %s.%s to a shift register with depth %d.\n",
 				log_id(module), log_id(first_cell), log_id(module), log_id(last_cell), depth);
 
@@ -205,8 +275,6 @@ struct ShregmapWorker
 				shreg_cell_type_str += first_cell->type.substr(1);
 			}
 
-			IdString q_port = opts.ffcells.at(first_cell->type).second;
-
 			if (opts.init) {
 				vector<State> initval;
 				for (int i = depth-1; i >= 0; i--) {
@@ -250,6 +318,9 @@ struct ShregmapWorker
 			first_cell->setPort(q_port, last_cell->getPort(q_port));
 			first_cell->setParam("\\DEPTH", depth);
 
+			if (opts.tech != nullptr && !opts.tech->fixup_shreg(first_cell, taps))
+				remove_cells.insert(first_cell);
+
 			for (int i = 1; i < depth; i++)
 				remove_cells.insert(chain[cursor+i]);
 			cursor += depth;
@@ -354,13 +425,16 @@ struct ShregmapPass : public Pass {
 		log("        generated cells with the initialization value. (first bit to shift out\n");
 		log("        in LSB position)\n");
 		log("\n");
+		log("    -tech greenpak4\n");
+		log("        map to greenpak4 shift registers.\n");
+		log("\n");
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
 		ShregmapOptions opts;
 		string clkpol, enpol;
 
-		log_header("Executing SHREGMAP pass (map shift registers).\n");
+		log_header(design, "Executing SHREGMAP pass (map shift registers).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
@@ -401,6 +475,18 @@ struct ShregmapPass : public Pass {
 				opts.keep_after = atoi(args[++argidx].c_str());
 				continue;
 			}
+			if (args[argidx] == "-tech" && argidx+1 < args.size() && opts.tech == nullptr) {
+				string tech = args[++argidx];
+				if (tech == "greenpak4") {
+					clkpol = "pos";
+					opts.maxlen = 16;
+					opts.tech = new ShregmapTechGreenpak4;
+				} else {
+					argidx--;
+					break;
+				}
+				continue;
+			}
 			if (args[argidx] == "-zinit") {
 				opts.zinit = true;
 				continue;
@@ -467,6 +553,11 @@ struct ShregmapPass : public Pass {
 		}
 
 		log("Converted %d dff cells into %d shift registers.\n", dff_count, shreg_count);
+
+		if (opts.tech != nullptr) {
+			delete opts.tech;
+			opts.tech = nullptr;
+		}
 	}
 } ShregmapPass;
 
diff --git a/passes/techmap/simplemap.cc b/passes/techmap/simplemap.cc
index f6ac3964b..777e80142 100644
--- a/passes/techmap/simplemap.cc
+++ b/passes/techmap/simplemap.cc
@@ -543,7 +543,7 @@ struct SimplemapPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing SIMPLEMAP pass (map simple cells to gate primitives).\n");
+		log_header(design, "Executing SIMPLEMAP pass (map simple cells to gate primitives).\n");
 		extra_args(args, 1, design);
 
 		std::map<RTLIL::IdString, void(*)(RTLIL::Module*, RTLIL::Cell*)> mappers;
diff --git a/passes/techmap/techmap.cc b/passes/techmap/techmap.cc
index 5334ebfaf..8bbcc3dfe 100644
--- a/passes/techmap/techmap.cc
+++ b/passes/techmap/techmap.cc
@@ -779,7 +779,7 @@ struct TechmapWorker
 
 					if (recursive_mode) {
 						if (log_continue) {
-							log_header("Continuing TECHMAP pass.\n");
+							log_header(design, "Continuing TECHMAP pass.\n");
 							log_continue = false;
 						}
 						while (techmap_module(map, tpl, map, handled_cells, celltypeMap, true)) { }
@@ -790,7 +790,7 @@ struct TechmapWorker
 					continue;
 
 				if (log_continue) {
-					log_header("Continuing TECHMAP pass.\n");
+					log_header(design, "Continuing TECHMAP pass.\n");
 					log_continue = false;
 				}
 
@@ -833,7 +833,7 @@ struct TechmapWorker
 		}
 
 		if (log_continue) {
-			log_header("Continuing TECHMAP pass.\n");
+			log_header(design, "Continuing TECHMAP pass.\n");
 			log_continue = false;
 		}
 
@@ -976,7 +976,7 @@ struct TechmapPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing TECHMAP pass (map to technology primitives).\n");
+		log_header(design, "Executing TECHMAP pass (map to technology primitives).\n");
 		log_push();
 
 		TechmapWorker worker;
@@ -1108,7 +1108,7 @@ struct FlattenPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing FLATTEN pass (flatten design).\n");
+		log_header(design, "Executing FLATTEN pass (flatten design).\n");
 		log_push();
 
 		extra_args(args, 1, design);
diff --git a/passes/techmap/tribuf.cc b/passes/techmap/tribuf.cc
index d0564b4ea..03629082c 100644
--- a/passes/techmap/tribuf.cc
+++ b/passes/techmap/tribuf.cc
@@ -160,7 +160,7 @@ struct TribufPass : public Pass {
 	{
 		TribufConfig config;
 
-		log_header("Executing TRIBUF pass.\n");
+		log_header(design, "Executing TRIBUF pass.\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++) {
diff --git a/passes/tests/test_autotb.cc b/passes/tests/test_autotb.cc
index bb516fca9..f42a58af5 100644
--- a/passes/tests/test_autotb.cc
+++ b/passes/tests/test_autotb.cc
@@ -333,7 +333,7 @@ struct TestAutotbBackend : public Backend {
 	{
 		int num_iter = 1000;
 
-		log_header("Executing TEST_AUTOTB backend (auto-generate pseudo-random test benches).\n");
+		log_header(design, "Executing TEST_AUTOTB backend (auto-generate pseudo-random test benches).\n");
 
 		int argidx;
 		for (argidx = 1; argidx < GetSize(args); argidx++)
diff --git a/techlibs/common/prep.cc b/techlibs/common/prep.cc
index 911737947..255306488 100644
--- a/techlibs/common/prep.cc
+++ b/techlibs/common/prep.cc
@@ -120,7 +120,7 @@ struct PrepPass : public Pass {
 
 		bool active = run_from.empty();
 
-		log_header("Executing PREP pass.\n");
+		log_header(design, "Executing PREP pass.\n");
 		log_push();
 
 		if (check_label(active, run_from, run_to, "begin"))
diff --git a/techlibs/common/synth.cc b/techlibs/common/synth.cc
index 8eb1aeba4..acfe888d9 100644
--- a/techlibs/common/synth.cc
+++ b/techlibs/common/synth.cc
@@ -132,7 +132,7 @@ struct SynthPass : public ScriptPass
 		if (!design->full_selection())
 			log_cmd_error("This comannd only operates on fully selected designs!\n");
 
-		log_header("Executing SYNTH pass.\n");
+		log_header(design, "Executing SYNTH pass.\n");
 		log_push();
 
 		run_script(design, run_from, run_to);
diff --git a/techlibs/greenpak4/greenpak4_counters.cc b/techlibs/greenpak4/greenpak4_counters.cc
index 7b5646bf2..998bb73bd 100644
--- a/techlibs/greenpak4/greenpak4_counters.cc
+++ b/techlibs/greenpak4/greenpak4_counters.cc
@@ -408,7 +408,7 @@ struct Greenpak4CountersPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing GREENPAK4_COUNTERS pass (mapping counters to hard IP blocks).\n");
+		log_header(design, "Executing GREENPAK4_COUNTERS pass (mapping counters to hard IP blocks).\n");
 		
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/techlibs/greenpak4/synth_greenpak4.cc b/techlibs/greenpak4/synth_greenpak4.cc
index 8900d8d78..463971d41 100644
--- a/techlibs/greenpak4/synth_greenpak4.cc
+++ b/techlibs/greenpak4/synth_greenpak4.cc
@@ -169,7 +169,7 @@ struct SynthGreenPAK4Pass : public Pass {
 
 		bool active = run_from.empty();
 
-		log_header("Executing SYNTH_GREENPAK4 pass.\n");
+		log_header(design, "Executing SYNTH_GREENPAK4 pass.\n");
 		log_push();
 
 		if (check_label(active, run_from, run_to, "begin"))
diff --git a/techlibs/ice40/ice40_ffinit.cc b/techlibs/ice40/ice40_ffinit.cc
index 8c4b9a37d..db2100381 100644
--- a/techlibs/ice40/ice40_ffinit.cc
+++ b/techlibs/ice40/ice40_ffinit.cc
@@ -37,7 +37,7 @@ struct Ice40FfinitPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing ICE40_FFINIT pass (implement FF init values).\n");
+		log_header(design, "Executing ICE40_FFINIT pass (implement FF init values).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/techlibs/ice40/ice40_ffssr.cc b/techlibs/ice40/ice40_ffssr.cc
index 9ebc3c0d7..9a6d69df0 100644
--- a/techlibs/ice40/ice40_ffssr.cc
+++ b/techlibs/ice40/ice40_ffssr.cc
@@ -35,7 +35,7 @@ struct Ice40FfssrPass : public Pass {
 	}
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
-		log_header("Executing ICE40_FFSSR pass (merge synchronous set/reset into FF cells).\n");
+		log_header(design, "Executing ICE40_FFSSR pass (merge synchronous set/reset into FF cells).\n");
 
 		size_t argidx;
 		for (argidx = 1; argidx < args.size(); argidx++)
diff --git a/techlibs/ice40/ice40_opt.cc b/techlibs/ice40/ice40_opt.cc
index 5730847ce..8b6a23fb2 100644
--- a/techlibs/ice40/ice40_opt.cc
+++ b/techlibs/ice40/ice40_opt.cc
@@ -137,7 +137,7 @@ struct Ice40OptPass : public Pass {
 	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
 	{
 		string opt_expr_args = "-mux_undef -undriven";
-		log_header("Executing ICE40_OPT pass (performing simple optimizations).\n");
+		log_header(design, "Executing ICE40_OPT pass (performing simple optimizations).\n");
 		log_push();
 
 		size_t argidx;
@@ -154,7 +154,7 @@ struct Ice40OptPass : public Pass {
 		{
 			design->scratchpad_unset("opt.did_something");
 
-			log_header("Running ICE40 specific optimizations.\n");
+			log_header(design, "Running ICE40 specific optimizations.\n");
 			for (auto module : design->selected_modules())
 				run_ice40_opts(module);
 
@@ -166,14 +166,14 @@ struct Ice40OptPass : public Pass {
 			if (design->scratchpad_get_bool("opt.did_something") == false)
 				break;
 
-			log_header("Rerunning OPT passes. (Removed registers in this run.)\n");
+			log_header(design, "Rerunning OPT passes. (Removed registers in this run.)\n");
 		}
 
 		design->optimize();
 		design->sort();
 		design->check();
 
-		log_header("Finished OPT passes. (There is nothing left to do.)\n");
+		log_header(design, "Finished OPT passes. (There is nothing left to do.)\n");
 		log_pop();
 	}
 } Ice40OptPass;
diff --git a/techlibs/ice40/synth_ice40.cc b/techlibs/ice40/synth_ice40.cc
index 2ed7642ae..3dbdde3df 100644
--- a/techlibs/ice40/synth_ice40.cc
+++ b/techlibs/ice40/synth_ice40.cc
@@ -149,7 +149,7 @@ struct SynthIce40Pass : public ScriptPass
 		if (!design->full_selection())
 			log_cmd_error("This comannd only operates on fully selected designs!\n");
 
-		log_header("Executing SYNTH_ICE40 pass.\n");
+		log_header(design, "Executing SYNTH_ICE40 pass.\n");
 		log_push();
 
 		run_script(design, run_from, run_to);
diff --git a/techlibs/xilinx/synth_xilinx.cc b/techlibs/xilinx/synth_xilinx.cc
index 524fd1d4e..e7ec1e6e8 100644
--- a/techlibs/xilinx/synth_xilinx.cc
+++ b/techlibs/xilinx/synth_xilinx.cc
@@ -160,7 +160,7 @@ struct SynthXilinxPass : public Pass {
 
 		bool active = run_from.empty();
 
-		log_header("Executing SYNTH_XILINX pass.\n");
+		log_header(design, "Executing SYNTH_XILINX pass.\n");
 		log_push();
 
 		if (check_label(active, run_from, run_to, "begin"))
diff --git a/tests/simple/memory.v b/tests/simple/memory.v
index d58ed9d1a..9fddce26c 100644
--- a/tests/simple/memory.v
+++ b/tests/simple/memory.v
@@ -243,3 +243,24 @@ module memtest10(input clk, input [5:0] din, output [5:0] dout);
 
 	assign dout = queue[3];
 endmodule
+
+// ----------------------------------------------------------
+
+module memtest11(clk, wen, waddr, raddr, wdata, rdata);
+	input clk, wen;
+	input [1:0] waddr, raddr;
+	input [7:0] wdata;
+	output [7:0] rdata;
+
+	reg [7:0] mem [3:0];
+
+	assign rdata = mem[raddr];
+
+	always @(posedge clk) begin
+		if (wen)
+			mem[waddr] <= wdata;
+		else
+			mem[waddr] <= mem[waddr];
+	end
+endmodule
+