Merge remote-tracking branch 'origin/clifford/async2synclatch' into Sergey/tests_ice40

67 files changed, 3616 insertions, 586 deletions

diff --git a/Brewfile b/Brewfile
index 0c58ce161..4ffe50e86 100644
--- a/Brewfile
+++ b/Brewfile
@@ -6,3 +6,4 @@ brew "git"
 brew "graphviz"
 brew "pkg-config"
 brew "python3"
+brew "tcl-tk"
diff --git a/CHANGELOG b/CHANGELOG
index 291c8d249..f7774cb9e 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -12,43 +12,149 @@ Yosys 0.9 .. Yosys 0.9-dev
     - Added "synth_xilinx -abc9" (experimental)
     - Added "synth_ice40 -abc9" (experimental)
     - Added "synth -abc9" (experimental)
-    - Added "script -scriptwire
+    - Added "script -scriptwire"
+    - Added "synth_xilinx -nocarry"
+    - Added "synth_xilinx -nowidelut"
+    - Added "synth_ecp5 -nowidelut"
     - "synth_xilinx" to now infer wide multiplexers (-widemux <min> to enable)
+    - Renamed labels/options in synth_ice40 (e.g. dram -> map_lutram; -nodram -> -nolutram)
+    - Renamed labels/options in synth_ecp5 (e.g. dram -> map_lutram; -nodram -> -nolutram)
+    - Renamed labels in synth_intel (e.g. bram -> map_bram)
+    - Renamed labels/options in synth_xilinx (e.g. dram -> map_lutram; -nodram -> -nolutram)
     - Added automatic gzip decompression for frontends
     - Added $_NMUX_ cell type
     - Added automatic gzip compression (based on filename extension) for backends
     - Improve attribute and parameter encoding in JSON to avoid ambiguities between
       bit vectors and strings containing [01xz]*
+    - Added "clkbufmap" pass
+    - Added "synth_xilinx -family xc6s" for Spartan 6 support (experimental)
+    - Added "synth_xilinx -ise" (experimental)
+    - Added "synth_xilinx -iopad"
+    - "synth_xilinx" now automatically inserts clock buffers (add -noclkbuf to disable)
+    - Improvements in pmgen: subpattern and recursive matches
     - Added "opt_share" pass, run as part of "opt -full"
     - Added "ice40_wrapcarry" to encapsulate SB_LUT+SB_CARRY pairs for techmapping
     - Removed "ice40_unlut"
+    - Improvements in pmgen: slices, choices, define, generate
 
-Yosys 0.8 .. Yosys 0.8-dev
---------------------------
+Yosys 0.8 .. Yosys 0.9
+----------------------
 
  * Various
-    - Added $changed support to read_verilog
+    - Many bugfixes and small improvements
+    - Added support for SystemVerilog interfaces and modports
     - Added "write_edif -attrprop"
-    - Added "ice40_unlut" pass
     - Added "opt_lut" pass
-    - Added "synth_ice40 -relut"
-    - Added "synth_ice40 -noabc"
     - Added "gate2lut.v" techmap rule
     - Added "rename -src"
     - Added "equiv_opt" pass
-    - Added "shregmap -tech xilinx"
+    - Added "flowmap" LUT mapping pass
+    - Added "rename -wire" to rename cells based on the wires they drive
+    - Added "bugpoint" for creating minimised testcases
+    - Added "write_edif -gndvccy"
+    - "write_verilog" to escape Verilog keywords
+    - Fixed sign handling of real constants
+    - "write_verilog" to write initial statement for initial flop state
+    - Added pmgen pattern matcher generator
+    - Fixed opt_rmdff handling of $_DFFSR_???_ and $_DLATCHSR_???_
+    - Added "setundef -params" to replace undefined cell parameters
+    - Renamed "yosys -D" to "yosys -U", added "yosys -D" to set Verilog defines
+    - Fixed handling of defparam when default_nettype is none
+    - Fixed "wreduce" flipflop handling
+    - Fixed FIRRTL to Verilog process instance subfield assignment
+    - Added "write_verilog -siminit"
+    - Several fixes and improvements for mem2reg memories
+    - Fixed handling of task output ports in clocked always blocks
+    - Improved handling of and-with-1 and or-with-0 in "opt_expr"
     - Added "read_aiger" frontend
+    - Added "mutate" pass
+    - Added "hdlname" attribute
+    - Added "rename -output"
+    - Added "read_ilang -lib"
+    - Improved "proc" full_case detection and handling
+    - Added "whitebox" and "lib_whitebox" attributes
+    - Added "read_verilog -nowb", "flatten -wb" and "wbflip"
+    - Added Python bindings and support for Python plug-ins
+    - Added "pmux2shiftx"
+    - Added log_debug framework for reduced default verbosity
+    - Improved "opt_expr" and "opt_clean" handling of (partially) undriven and/or unused wires
+    - Added "peepopt" peephole optimisation pass using pmgen
+    - Added approximate support for SystemVerilog "var" keyword
+    - Added parsing of "specify" blocks into $specrule and $specify[23]
+    - Added support for attributes on parameters and localparams
+    - Added support for parsing attributes on port connections
+    - Added "wreduce -keepdc"
+    - Added support for optimising $dffe and $_DFFE_* cells in "opt_rmdff"
+    - Added Verilog wand/wor wire type support
+    - Added support for elaboration system tasks
     - Added "muxcover -mux{4,8,16}=<cost>"
     - Added "muxcover -dmux=<cost>"
     - Added "muxcover -nopartial"
     - Added "muxpack" pass
     - Added "pmux2shiftx -norange"
+    - Added support for "~" in filename parsing
+    - Added "read_verilog -pwires" feature to turn parameters into wires
+    - Fixed sign extension of unsized constants with 'bx and 'bz MSB
+    - Fixed genvar to be a signed type
+    - Added support for attributes on case rules
+    - Added "upto" and "offset" to JSON frontend and backend
+    - Several liberty file parser improvements
+    - Fixed handling of more complex BRAM patterns
+    - Add "write_aiger -I -O -B"
+
+ * Formal Verification
+    - Added $changed support to read_verilog
+    - Added "read_verilog -noassert -noassume -assert-assumes"
+    - Added btor ops for $mul, $div, $mod and $concat
+    - Added yosys-smtbmc support for btor witnesses
+    - Added "supercover" pass
+    - Fixed $global_clock handling vs autowire
+    - Added $dffsr support to "async2sync"
+    - Added "fmcombine" pass
+    - Added memory init support in "write_btor"
+    - Added "cutpoint" pass
+    - Changed "ne" to "neq" in btor2 output
+    - Added support for SVA "final" keyword
+    - Added "fmcombine -initeq -anyeq"
+    - Added timescale and generated-by header to yosys-smtbmc vcd output
+    - Improved BTOR2 handling of undriven wires
+
+ * Verific support
+    - Enabled Verific flags vhdl_support_variable_slice and veri_elaborate_top_level_modules_having_interface_ports
+    - Improved support for asymmetric memories
+    - Added "verific -chparam"
+    - Fixed "verific -extnets" for more complex situations
+    - Added "read -verific" and "read -noverific"
+    - Added "hierarchy -chparam"
+
+ * New back-ends
+    - Added initial Anlogic support
+    - Added initial SmartFusion2 and IGLOO2 support
+
+ * ECP5 support
+    - Added "synth_ecp5 -nowidelut"
+    - Added BRAM inference support to "synth_ecp5"
+    - Added support for transforming Diamond IO and flipflop primitives
+
+ * iCE40 support
+    - Added "ice40_unlut" pass
+    - Added "synth_ice40 -relut"
+    - Added "synth_ice40 -noabc"
+    - Added "synth_ice40 -dffe_min_ce_use"
+    - Added DSP inference support using pmgen
+    - Added support for initialising BRAM primitives from a file
+    - Added iCE40 Ultra RGB LED driver cells
+
+ * Xilinx support
+    - Use "write_edif -pvector bra" for Xilinx EDIF files
+    - Fixes for VPR place and route support with "synth_xilinx"
+    - Added more cell simulation models
+    - Added "synth_xilinx -family"
+    - Added "stat -tech xilinx" to estimate logic cell usage
     - Added "synth_xilinx -nocarry"
     - Added "synth_xilinx -nowidelut"
-    - Added "synth_ecp5 -nowidelut"
     - "synth_xilinx" to now infer hard shift registers (-nosrl to disable)
-    - Fixed sign extension of unsized constants with 'bx and 'bz MSB
-
+    - Added support for mapping RAM32X1D
 
 Yosys 0.7 .. Yosys 0.8
 ----------------------
diff --git a/COPYING b/COPYING
index a121cdfe9..0839088c3 100644
--- a/COPYING
+++ b/COPYING
@@ -1,4 +1,4 @@
-Copyright (C) 2012 - 2018  Clifford Wolf <clifford@clifford.at>
+Copyright (C) 2012 - 2019  Clifford Wolf <clifford@clifford.at>
 
 Permission to use, copy, modify, and/or distribute this software for any
 purpose with or without fee is hereby granted, provided that the above
diff --git a/CodingReadme b/CodingReadme
index b64e79178..8212436e5 100644
--- a/CodingReadme
+++ b/CodingReadme
@@ -390,6 +390,7 @@ Finally run all tests with "make config-{clang,gcc,gcc-4.8}":
 Release:
 
 	- set YOSYS_VER to x.y.z in Makefile
+	- remove "bumpversion" target from Makefile
 	- update version string in CHANGELOG
 	git commit -am "Yosys x.y.z"
 
diff --git a/Makefile b/Makefile
index 9cfa6a0de..2b473df6e 100644
--- a/Makefile
+++ b/Makefile
@@ -91,8 +91,10 @@ PLUGIN_LDFLAGS += -undefined dynamic_lookup
 ifneq ($(shell which brew),)
 BREW_PREFIX := $(shell brew --prefix)/opt
 $(info $$BREW_PREFIX is [${BREW_PREFIX}])
+ifeq ($(ENABLE_PYOSYS),1)
 CXXFLAGS += -I$(BREW_PREFIX)/boost/include/boost
 LDFLAGS += -L$(BREW_PREFIX)/boost/lib
+endif
 CXXFLAGS += -I$(BREW_PREFIX)/readline/include
 LDFLAGS += -L$(BREW_PREFIX)/readline/lib
 PKG_CONFIG_PATH := $(BREW_PREFIX)/libffi/lib/pkgconfig:$(PKG_CONFIG_PATH)
@@ -113,10 +115,13 @@ LDFLAGS += -rdynamic
 LDLIBS += -lrt
 endif
 
-YOSYS_VER := 0.8+$(shell cd $(YOSYS_SRC) && test -e .git && { git log --author=clifford@clifford.at --oneline 4d4665b.. 2> /dev/null | wc -l; })
+YOSYS_VER := 0.9+1
 GIT_REV := $(shell cd $(YOSYS_SRC) && git rev-parse --short HEAD 2> /dev/null || echo UNKNOWN)
 OBJS = kernel/version_$(GIT_REV).o
 
+bumpversion:
+	sed -i "/^YOSYS_VER := / s/+[0-9][0-9]*$$/+`git log --oneline 8a4c6e6.. | wc -l`/;" Makefile
+
 # set 'ABCREV = default' to use abc/ as it is
 #
 # Note: If you do ABC development, make sure that 'abc' in this directory
@@ -487,6 +492,11 @@ define add_include_file
 $(eval $(call add_share_file,$(dir share/include/$(1)),$(1)))
 endef
 
+define add_extra_objs
+EXTRA_OBJS += $(1)
+.SECONDARY: $(1)
+endef
+
 ifeq ($(PRETTY), 1)
 P_STATUS = 0
 P_OFFSET = 0
diff --git a/README.md b/README.md
index d9989eb29..38ca77862 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,7 @@
 ```
 yosys -- Yosys Open SYnthesis Suite
 
-Copyright (C) 2012 - 2018  Clifford Wolf <clifford@clifford.at>
+Copyright (C) 2012 - 2019  Clifford Wolf <clifford@clifford.at>
 
 Permission to use, copy, modify, and/or distribute this software for any
 purpose with or without fee is hereby granted, provided that the above
@@ -69,11 +69,14 @@ prerequisites for building yosys:
 		graphviz xdot pkg-config python3 libboost-system-dev \
 		libboost-python-dev libboost-filesystem-dev zlib1g-dev
 
-Similarily, on Mac OS X MacPorts or Homebrew can be used to install dependencies:
+Similarily, on Mac OS X Homebrew can be used to install dependencies:
 
 	$ brew tap Homebrew/bundle && brew bundle
+
+or MacPorts:
+
 	$ sudo port install bison flex readline gawk libffi \
-		git graphviz pkgconfig python36 boost zlib
+		git graphviz pkgconfig python36 boost zlib tcl
 
 On FreeBSD use the following command to install all prerequisites:
 
@@ -329,6 +332,21 @@ Verilog Attributes and non-standard features
   that represent module parameters or localparams (when the HDL front-end
   is run in -pwires mode).
 
+- The ``clkbuf_driver`` attribute can be set on an output port of a blackbox
+  module to mark it as a clock buffer output, and thus prevent ``clkbufmap``
+  from inserting another clock buffer on a net driven by such output.
+
+- The ``clkbuf_sink`` attribute can be set on an input port of a module to
+  request clock buffer insertion by the ``clkbufmap`` pass.
+
+- The ``clkbuf_inhibit`` is the default attribute to set on a wire to prevent
+  automatic clock buffer insertion by ``clkbufmap``. This behaviour can be
+  overridden by providing a custom selection to ``clkbufmap``.
+
+- The ``iopad_external_pin`` attribute on a blackbox module's port marks
+  it as the external-facing pin of an I/O pad, and prevents ``iopadmap``
+  from inserting another pad cell on it.
+
 - In addition to the ``(* ... *)`` attribute syntax, Yosys supports
   the non-standard ``{* ... *}`` attribute syntax to set default attributes
   for everything that comes after the ``{* ... *}`` statement. (Reset
@@ -405,6 +423,23 @@ Verilog Attributes and non-standard features
   blackboxes and whiteboxes. Use ``read_verilog -specify`` to enable this
   functionality. (By default specify .. endspecify blocks are ignored.)
 
+- The module attribute ``abc_box_id`` specifies a positive integer linking a
+  blackbox or whitebox definition to a corresponding entry in a `abc9`
+  box-file.
+
+- The port attribute ``abc_scc_break`` indicates a module input port that will
+  be treated as a primary output during `abc9` techmapping. Doing so eliminates
+  the possibility of a strongly-connected component (i.e. a combinatorial loop)
+  existing. Typically, this is specified for sequential inputs on otherwise
+  combinatorial boxes -- for example, applying ``abc_scc_break`` onto the `D`
+  port of a LUTRAM cell prevents `abc9` from interpreting any `Q` -> `D` paths
+  as a combinatorial loop.
+
+- The port attribute ``abc_carry`` marks the carry-in (if an input port) and
+  carry-out (if output port) ports of a box. This information is necessary for
+  `abc9` to preserve the integrity of carry-chains. Specifying this attribute
+  onto a bus port will affect only its most significant bit.
+
 
 Non-standard or SystemVerilog features for formal verification
 ==============================================================
diff --git a/backends/aiger/xaiger.cc b/backends/aiger/xaiger.cc
index 5e12e9a34..77d0e94c2 100644
--- a/backends/aiger/xaiger.cc
+++ b/backends/aiger/xaiger.cc
@@ -326,7 +326,6 @@ struct XAigerWriter
 #endif
 			log_assert(no_loops);
 
-			pool<IdString> seen_boxes;
 			for (auto cell_name : toposort.sorted) {
 				RTLIL::Cell *cell = module->cell(cell_name);
 				log_assert(cell);
@@ -335,47 +334,6 @@ struct XAigerWriter
 				if (!box_module || !box_module->attributes.count("\\abc_box_id"))
 					continue;
 
-				if (seen_boxes.insert(cell->type).second) {
-					auto it = box_module->attributes.find("\\abc_carry");
-					if (it != box_module->attributes.end()) {
-						RTLIL::Wire *carry_in = nullptr, *carry_out = nullptr;
-						auto carry_in_out = it->second.decode_string();
-						auto pos = carry_in_out.find(',');
-						if (pos == std::string::npos)
-							log_error("'abc_carry' attribute on module '%s' does not contain ','.\n", log_id(cell->type));
-						auto carry_in_name = RTLIL::escape_id(carry_in_out.substr(0, pos));
-						carry_in = box_module->wire(carry_in_name);
-						if (!carry_in || !carry_in->port_input)
-							log_error("'abc_carry' on module '%s' contains '%s' which does not exist or is not an input port.\n", log_id(cell->type), carry_in_name.c_str());
-
-						auto carry_out_name = RTLIL::escape_id(carry_in_out.substr(pos+1));
-						carry_out = box_module->wire(carry_out_name);
-						if (!carry_out || !carry_out->port_output)
-							log_error("'abc_carry' on module '%s' contains '%s' which does not exist or is not an output port.\n", log_id(cell->type), carry_out_name.c_str());
-
-						auto &ports = box_module->ports;
-						for (auto jt = ports.begin(); jt != ports.end(); ) {
-							RTLIL::Wire* w = box_module->wire(*jt);
-							log_assert(w);
-							if (w == carry_in || w == carry_out) {
-								jt = ports.erase(jt);
-								continue;
-							}
-							if (w->port_id > carry_in->port_id)
-								--w->port_id;
-							if (w->port_id > carry_out->port_id)
-								--w->port_id;
-							log_assert(w->port_input || w->port_output);
-							log_assert(ports[w->port_id-1] == w->name);
-							++jt;
-						}
-						ports.push_back(carry_in->name);
-						carry_in->port_id = ports.size();
-						ports.push_back(carry_out->name);
-						carry_out->port_id = ports.size();
-					}
-				}
-
 				// Fully pad all unused input connections of this box cell with S0
 				// Fully pad all undriven output connections of this box cell with anonymous wires
 				// NB: Assume box_module->ports are sorted alphabetically
diff --git a/examples/mimas2/run_yosys.ys b/examples/mimas2/run_yosys.ys
index b3204b1ca..b48877811 100644
--- a/examples/mimas2/run_yosys.ys
+++ b/examples/mimas2/run_yosys.ys
@@ -1,4 +1,3 @@
 read_verilog example.v
-synth_xilinx -top example -family xc6s
-iopadmap -bits -outpad OBUF I:O -inpad IBUF O:I
+synth_xilinx -top example -family xc6s -ise
 write_edif -pvector bra example.edif
diff --git a/frontends/ast/ast.cc b/frontends/ast/ast.cc
index 0d6626b19..82283fb5b 100644
--- a/frontends/ast/ast.cc
+++ b/frontends/ast/ast.cc
@@ -1502,7 +1502,10 @@ std::string AstModule::derive_common(RTLIL::Design *design, dict<RTLIL::IdString
 	rewrite_parameter:
 			para_info += stringf("%s=%s", child->str.c_str(), log_signal(RTLIL::SigSpec(parameters[para_id])));
 			delete child->children.at(0);
-			if ((parameters[para_id].flags & RTLIL::CONST_FLAG_STRING) != 0)
+			if ((parameters[para_id].flags & RTLIL::CONST_FLAG_REAL) != 0) {
+				child->children[0] = new AstNode(AST_REALVALUE);
+				child->children[0]->realvalue = std::stod(parameters[para_id].decode_string());
+			} else if ((parameters[para_id].flags & RTLIL::CONST_FLAG_STRING) != 0)
 				child->children[0] = AstNode::mkconst_str(parameters[para_id].decode_string());
 			else
 				child->children[0] = AstNode::mkconst_bits(parameters[para_id].bits, (parameters[para_id].flags & RTLIL::CONST_FLAG_SIGNED) != 0);
diff --git a/frontends/ast/simplify.cc b/frontends/ast/simplify.cc
index 54b9efaad..86dd80c65 100644
--- a/frontends/ast/simplify.cc
+++ b/frontends/ast/simplify.cc
@@ -150,6 +150,11 @@ bool AstNode::simplify(bool const_fold, bool at_zero, bool in_lvalue, int stage,
 					reg->str = stringf("%s[%d]", node->str.c_str(), i);
 					reg->is_reg = true;
 					reg->is_signed = node->is_signed;
+					for (auto &it : node->attributes)
+						if (it.first != ID(mem2reg))
+							reg->attributes.emplace(it.first, it.second->clone());
+					reg->filename = node->filename;
+					reg->linenum = node->linenum;
 					children.push_back(reg);
 					while (reg->simplify(true, false, false, 1, -1, false, false)) { }
 				}
diff --git a/kernel/yosys.cc b/kernel/yosys.cc
index 747f2d739..5018a4888 100644
--- a/kernel/yosys.cc
+++ b/kernel/yosys.cc
@@ -129,7 +129,7 @@ void yosys_banner()
 	log(" |                                                                            |\n");
 	log(" |  yosys -- Yosys Open SYnthesis Suite                                       |\n");
 	log(" |                                                                            |\n");
-	log(" |  Copyright (C) 2012 - 2018  Clifford Wolf <clifford@clifford.at>           |\n");
+	log(" |  Copyright (C) 2012 - 2019  Clifford Wolf <clifford@clifford.at>           |\n");
 	log(" |                                                                            |\n");
 	log(" |  Permission to use, copy, modify, and/or distribute this software for any  |\n");
 	log(" |  purpose with or without fee is hereby granted, provided that the above    |\n");
diff --git a/misc/py_wrap_generator.py b/misc/py_wrap_generator.py
index 66d661fa1..2bf364470 100644
--- a/misc/py_wrap_generator.py
+++ b/misc/py_wrap_generator.py
@@ -508,23 +508,17 @@ class TupleTranslator(PythonDictTranslator):
 	#Generate c++ code to translate to a boost::python::tuple
 	@classmethod
 	def translate_cpp(c, varname, types, prefix, ref):
-		text  = prefix + TupleTranslator.typename + " " + varname + "___tmp = boost::python::make_tuple(" + varname + ".first, " + varname + ".second);"
-		return text
-		tmp_name = "tmp_" + str(Translator.tmp_cntr)
-		Translator.tmp_cntr = Translator.tmp_cntr + 1
-		if ref:
-			text += prefix + "for(auto " + tmp_name + " : *" + varname + ")"
+		# if the tuple is a pair of SigSpecs (aka SigSig), then we need
+		# to call get_py_obj() on each item in the tuple
+		if types[0].name in classnames:
+			first_var = types[0].name + "::get_py_obj(" + varname + ".first)"
 		else:
-			text += prefix + "for(auto " + tmp_name + " : " + varname + ")"
-		text += prefix + "{"
-		if types[0].name.split(" ")[-1] in primitive_types or types[0].name in enum_names:
-			text += prefix + "\t" + varname + "___tmp.append(" + tmp_name + ");"
-		elif types[0].name in known_containers:
-			text += known_containers[types[0].name].translate_cpp(tmp_name, types[0].cont.args, prefix + "\t", types[1].attr_type == attr_types.star)
-			text += prefix + "\t" + varname + "___tmp.append(" + types[0].name + "::get_py_obj(" + tmp_name + "___tmp);"
-		elif types[0].name in classnames:
-			text += prefix + "\t" + varname + "___tmp.append(" + types[0].name + "::get_py_obj(" + tmp_name + "));"
-		text += prefix + "}"
+			first_var = varname + ".first"
+		if types[1].name in classnames:
+			second_var = types[1].name + "::get_py_obj(" + varname + ".second)"
+		else:
+			second_var = varname + ".second"
+		text  = prefix + TupleTranslator.typename + " " + varname + "___tmp = boost::python::make_tuple(" + first_var + ", " + second_var + ");"
 		return text
 
 #Associate the Translators with their c++ type
diff --git a/passes/opt/opt_expr.cc b/passes/opt/opt_expr.cc
index 858b3560c..00d7d6063 100644
--- a/passes/opt/opt_expr.cc
+++ b/passes/opt/opt_expr.cc
@@ -369,7 +369,7 @@ void replace_const_cells(RTLIL::Design *design, RTLIL::Module *module, bool cons
 	for (auto cell : module->cells())
 		if (design->selected(module, cell) && cell->type[0] == '$') {
 			if (cell->type.in(ID($_NOT_), ID($not), ID($logic_not)) &&
-					cell->getPort(ID::A).size() == 1 && cell->getPort(ID::Y).size() == 1)
+					GetSize(cell->getPort(ID::A)) == 1 && GetSize(cell->getPort(ID::Y)) == 1)
 				invert_map[assign_map(cell->getPort(ID::Y))] = assign_map(cell->getPort(ID::A));
 			if (cell->type.in(ID($mux), ID($_MUX_)) &&
 					cell->getPort(ID::A) == SigSpec(State::S1) && cell->getPort(ID::B) == SigSpec(State::S0))
@@ -740,12 +740,34 @@ void replace_const_cells(RTLIL::Design *design, RTLIL::Module *module, bool cons
 				if (cell->type.in(ID($reduce_xor), ID($reduce_xnor), ID($lt), ID($le), ID($ge), ID($gt)))
 					replace_cell(assign_map, module, cell, "x-bit in input", ID::Y, RTLIL::State::Sx);
 				else
-					replace_cell(assign_map, module, cell, "x-bit in input", ID::Y, RTLIL::SigSpec(RTLIL::State::Sx, cell->getPort(ID::Y).size()));
+					replace_cell(assign_map, module, cell, "x-bit in input", ID::Y, RTLIL::SigSpec(RTLIL::State::Sx, GetSize(cell->getPort(ID::Y))));
 				goto next_cell;
 			}
 		}
 
-		if (cell->type.in(ID($_NOT_), ID($not), ID($logic_not)) && cell->getPort(ID::Y).size() == 1 &&
+		if (cell->type.in(ID($shiftx), ID($shift))) {
+			SigSpec sig_a = assign_map(cell->getPort(ID::A));
+			int width;
+			bool trim_x = cell->type == ID($shiftx) || !keepdc;
+			bool trim_0 = cell->type == ID($shift);
+			for (width = GetSize(sig_a); width > 1; width--) {
+				if ((trim_x && sig_a[width-1] == State::Sx) ||
+					(trim_0 && sig_a[width-1] == State::S0))
+					continue;
+				break;
+			}
+
+			if (width < GetSize(sig_a)) {
+				cover_list("opt.opt_expr.trim", "$shiftx", "$shift", cell->type.str());
+				sig_a.remove(width, GetSize(sig_a)-width);
+				cell->setPort(ID::A, sig_a);
+				cell->setParam(ID(A_WIDTH), width);
+				did_something = true;
+				goto next_cell;
+			}
+		}
+
+		if (cell->type.in(ID($_NOT_), ID($not), ID($logic_not)) && GetSize(cell->getPort(ID::Y)) == 1 &&
 				invert_map.count(assign_map(cell->getPort(ID::A))) != 0) {
 			cover_list("opt.opt_expr.invert.double", "$_NOT_", "$not", "$logic_not", cell->type.str());
 			replace_cell(assign_map, module, cell, "double_invert", ID::Y, invert_map.at(assign_map(cell->getPort(ID::A))));
@@ -1142,7 +1164,7 @@ void replace_const_cells(RTLIL::Design *design, RTLIL::Module *module, bool cons
 
 		if (mux_undef && cell->type.in(ID($mux), ID($pmux))) {
 			RTLIL::SigSpec new_a, new_b, new_s;
-			int width = cell->getPort(ID::A).size();
+			int width = GetSize(cell->getPort(ID::A));
 			if ((cell->getPort(ID::A).is_fully_undef() && cell->getPort(ID::B).is_fully_undef()) ||
 					cell->getPort(ID(S)).is_fully_undef()) {
 				cover_list("opt.opt_expr.mux_undef", "$mux", "$pmux", cell->type.str());
diff --git a/passes/pmgen/.gitignore b/passes/pmgen/.gitignore
index e52f3282f..6b319b8c3 100644
--- a/passes/pmgen/.gitignore
+++ b/passes/pmgen/.gitignore
@@ -1 +1 @@
-/*_pm.h
+/*_pm.h
\ No newline at end of file
diff --git a/passes/pmgen/Makefile.inc b/passes/pmgen/Makefile.inc
index c03606152..8e0cbdca8 100644
--- a/passes/pmgen/Makefile.inc
+++ b/passes/pmgen/Makefile.inc
@@ -1,30 +1,29 @@
-OBJS += passes/pmgen/ice40_dsp.o
-OBJS += passes/pmgen/ice40_wrapcarry.o
-OBJS += passes/pmgen/peepopt.o
+%_pm.h: passes/pmgen/pmgen.py %.pmg
+	$(P) mkdir -p passes/pmgen && python3 $< -o $@ -p $(subst _pm.h,,$(notdir $@)) $(filter-out $<,$^)
 
 # --------------------------------------
 
-passes/pmgen/ice40_dsp.o: passes/pmgen/ice40_dsp_pm.h
-EXTRA_OBJS += passes/pmgen/ice40_dsp_pm.h
-.SECONDARY: passes/pmgen/ice40_dsp_pm.h
+OBJS += passes/pmgen/test_pmgen.o
+passes/pmgen/test_pmgen.o: passes/pmgen/test_pmgen_pm.h passes/pmgen/ice40_dsp_pm.h passes/pmgen/peepopt_pm.h
+$(eval $(call add_extra_objs,passes/pmgen/test_pmgen_pm.h))
 
-passes/pmgen/ice40_dsp_pm.h: passes/pmgen/pmgen.py passes/pmgen/ice40_dsp.pmg
-	$(P) mkdir -p passes/pmgen && python3 $< -o $@ -p ice40_dsp $(filter-out $<,$^)
+# --------------------------------------
+
+OBJS += passes/pmgen/ice40_dsp.o
+passes/pmgen/ice40_dsp.o: passes/pmgen/ice40_dsp_pm.h
+$(eval $(call add_extra_objs,passes/pmgen/ice40_dsp_pm.h))
 
 # --------------------------------------
 
+OBJS += passes/pmgen/ice40_wrapcarry.o
 passes/pmgen/ice40_wrapcarry.o: passes/pmgen/ice40_wrapcarry_pm.h
-EXTRA_OBJS += passes/pmgen/ice40_wrapcarry_pm.h
-.SECONDARY: passes/pmgen/ice40_wrapcarry_pm.h
-
-passes/pmgen/ice40_wrapcarry_pm.h: passes/pmgen/pmgen.py passes/pmgen/ice40_wrapcarry.pmg
-	$(P) mkdir -p passes/pmgen && python3 $< -o $@ -p ice40_wrapcarry $(filter-out $<,$^)
+$(eval $(call add_extra_objs,passes/pmgen/ice40_wrapcarry_pm.h))
 
 # --------------------------------------
 
+OBJS += passes/pmgen/peepopt.o
 passes/pmgen/peepopt.o: passes/pmgen/peepopt_pm.h
-EXTRA_OBJS += passes/pmgen/peepopt_pm.h
-.SECONDARY: passes/pmgen/peepopt_pm.h
+$(eval $(call add_extra_objs,passes/pmgen/peepopt_pm.h))
 
 PEEPOPT_PATTERN  = passes/pmgen/peepopt_shiftmul.pmg
 PEEPOPT_PATTERN += passes/pmgen/peepopt_muldiv.pmg
diff --git a/passes/pmgen/README.md b/passes/pmgen/README.md
index 2f0b1fd5a..0856c9ba3 100644
--- a/passes/pmgen/README.md
+++ b/passes/pmgen/README.md
@@ -45,9 +45,9 @@ of type `foobar_pm::state_<pattern_name>_t`.)
 Similarly the `.pmg` file declares user data variables that become members of
 `.ud_<pattern_name>`, a struct of type `foobar_pm::udata_<pattern_name>_t`.
 
-There are four versions of the `run_<pattern_name>()` method: Without callback,
-callback without arguments, callback with reference to `pm`, and callback with
-reference to `pm.st_<pattern_name>`.
+There are three versions of the `run_<pattern_name>()` method: Without callback,
+callback without arguments, and callback with reference to `pm`. All versions
+of the `run_<pattern_name>()` method return the number of found matches.
 
 
 The .pmg File Format
@@ -118,8 +118,8 @@ write matchers:
   connected to any of the given signal bits, plus one if any of the signal
   bits is also a primary input or primary output.
 
-- In `code..endcode` blocks there exist `accept`, `reject`, and `branch`
-  statements.
+- In `code..endcode` blocks there exist `accept`, `reject`, `branch`,
+  `finish`, and `subpattern` statements.
 
 - In `index` statements there is a special `===` operator for the index
   lookup.
@@ -175,6 +175,48 @@ explore the case where `mul` is set to `nullptr`. Without the `optional`
 statement a match may only be assigned nullptr when one of the `if` expressions
 evaluates to `false`.
 
+The `semioptional` statement marks matches that must match if at least one
+matching cell exists, but if no matching cell exists it is set to `nullptr`.
+
+Slices and choices
+------------------
+
+Cell matches can contain "slices" and "choices". Slices can be used to
+create matches for different sections of a cell. For example:
+
+    state <int> pmux_slice
+
+    match pmux
+        select pmux->type == $pmux
+        slice idx GetSize(port(pmux, \S))
+        index <SigBit> port(pmux, \S)[idx] === port(eq, \Y)
+	set pmux_slice idx
+    endmatch
+
+The first argument to `slice` is the local variable name used to identify the
+slice. The second argument is the number of slices that should be created for
+this cell. The `set` statement can be used to copy that index into a state
+variable so that later matches and/or code blocks can refer to it.
+
+A similar mechanism is "choices", where a list of options is given as
+second argument, and the matcher will iterate over those options:
+
+    state <SigSpec> foo bar
+    state <IdString> eq_ab eq_ba
+
+    match eq
+        select eq->type == $eq
+        choice <IdString> AB {\A, \B}
+        define <IdString> BA (AB == \A ? \B : \A)
+        index <SigSpec> port(eq, AB) === foo
+        index <SigSpec> port(eq, BA) === bar
+        set eq_ab AB
+        set eq_ba BA
+    generate
+
+Notice how `define` can be used to define additional local variables similar
+to the loop variables defined by `slice` and `choice`.
+
 Additional code
 ---------------
 
@@ -232,5 +274,111 @@ But in some cases it is more natural to utilize the implicit branch statement:
         portAB = \B;
     endcode
 
-There is an implicit `code..endcode` block at the end of each `.pmg` file
-that just accepts everything that gets all the way there.
+There is an implicit `code..endcode` block at the end of each (sub)pattern
+that just rejects.
+
+A `code..finally..endcode` block executes the code after `finally` during
+back-tracking. This is useful for maintaining user data state or printing
+debug messages. For example:
+
+    udata <vector<Cell*>> stack
+
+    code
+        stack.push_back(addAB);
+        ...
+    finally
+        stack.pop_back();
+    endcode
+
+`accept` and `finish` statements can be used inside the `finally` section,
+but not `reject`, `branch`, or `subpattern`.
+
+Declaring a subpattern
+----------------------
+
+A subpattern starts with a line containing the `subpattern` keyword followed
+by the name of the subpattern. Subpatterns can be called from a `code` block
+using a `subpattern(<subpattern_name>);` C statement.
+
+Arguments may be passed to subpattern via state variables. The `subpattern`
+line must be followed by a `arg <arg1> <arg2> ...` line that lists the
+state variables used to pass arguments.
+
+    state <IdString> foobar_type
+    state <bool> foobar_state
+
+    code foobar_type foobar_state
+        foobar_state = false;
+        foobar_type = $add;
+        subpattern(foo);
+        foobar_type = $sub;
+        subpattern(bar);
+    endcode
+
+    subpattern foo
+    arg foobar_type foobar_state
+
+    match addsub
+        index <IdString> addsub->type === foobar_type
+        ...
+    endmatch
+
+    code
+        if (foobar_state) {
+            subpattern(tail);
+        } else {
+            foobar_state = true;
+            subpattern(bar);
+        }
+    endcode
+
+    subpattern bar
+    arg foobar_type foobar_state
+
+    match addsub
+        index <IdString> addsub->type === foobar_type
+        ...
+    endmatch
+
+    code
+        if (foobar_state) {
+            subpattern(tail);
+        } else {
+            foobar_state = true;
+            subpattern(foo);
+        }
+    endcode
+
+    subpattern tail
+    ...
+
+Subpatterns cann be called recursively.
+
+If a `subpattern` statement is preceded by a `fallthrough` statement, this is
+equivalent to calling the subpattern at the end of the preceding block.
+
+Generate Blocks
+---------------
+
+Match blocks may contain an optional `generate` section that is used for automatic
+test-case generation. For example:
+
+    match mul
+        ...
+    generate 10 0
+        SigSpec Y = port(ff, \D);
+        SigSpec A = module->addWire(NEW_ID, GetSize(Y) - rng(GetSize(Y)/2));
+        SigSpec B = module->addWire(NEW_ID, GetSize(Y) - rng(GetSize(Y)/2));
+        module->addMul(NEW_ID, A, B, Y, rng(2));
+    endmatch
+
+The expression `rng(n)` returns a non-negative integer less than `n`.
+
+The first argument to `generate` is the chance of this generate block being
+executed when the match block did not match anything, in percent.
+
+The second argument to `generate` is the chance of this generate block being
+executed when the match block did match something, in percent.
+
+The special statement `finish` can be used within generate blocks to terminate
+the current pattern matcher run.
diff --git a/passes/pmgen/ice40_dsp.pmg b/passes/pmgen/ice40_dsp.pmg
index 1f3590d4e..7003092bb 100644
--- a/passes/pmgen/ice40_dsp.pmg
+++ b/passes/pmgen/ice40_dsp.pmg
@@ -159,4 +159,5 @@ code clock clock_pol clock_vld
 		clock_pol = cp;
 		clock_vld = true;
 	}
+	accept;
 endcode
diff --git a/passes/pmgen/peepopt_muldiv.pmg b/passes/pmgen/peepopt_muldiv.pmg
index 06c275834..7cad759d0 100644
--- a/passes/pmgen/peepopt_muldiv.pmg
+++ b/passes/pmgen/peepopt_muldiv.pmg
@@ -32,5 +32,5 @@ code
 	log("muldiv pattern in %s: mul=%s, div=%s\n", log_id(module), log_id(mul), log_id(div));
 	module->connect(div_y, val_y);
 	autoremove(div);
-	reject;
+	accept;
 endcode
diff --git a/passes/pmgen/peepopt_shiftmul.pmg b/passes/pmgen/peepopt_shiftmul.pmg
index 6adab4e5f..d4748ae19 100644
--- a/passes/pmgen/peepopt_shiftmul.pmg
+++ b/passes/pmgen/peepopt_shiftmul.pmg
@@ -34,6 +34,7 @@ match mul
 endmatch
 
 code
+{
 	IdString const_factor_port = port(mul, \A).is_fully_const() ? \A : \B;
 	IdString const_factor_signed = const_factor_port == \A ? \A_SIGNED : \B_SIGNED;
 	Const const_factor_cnst = port(mul, const_factor_port).as_const();
@@ -90,5 +91,6 @@ code
 	shift->setParam(\B_WIDTH, GetSize(new_b));
 
 	blacklist(shift);
-	reject;
+	accept;
+}
 endcode
diff --git a/passes/pmgen/pmgen.py b/passes/pmgen/pmgen.py
index 81052afce..573722d68 100644
--- a/passes/pmgen/pmgen.py
+++ b/passes/pmgen/pmgen.py
@@ -38,7 +38,10 @@ for a in args:
 assert prefix is not None
 
 current_pattern = None
+current_subpattern = None
 patterns = dict()
+subpatterns = dict()
+subpattern_args = dict()
 state_types = dict()
 udata_types = dict()
 blocks = list()
@@ -104,9 +107,12 @@ def rewrite_cpp(s):
 
     return "".join(t)
 
-def process_pmgfile(f):
+def process_pmgfile(f, filename):
+    linenr = 0
     global current_pattern
+    global current_subpattern
     while True:
+        linenr += 1
         line = f.readline()
         if line == "": break
         line = line.strip()
@@ -119,19 +125,52 @@ def process_pmgfile(f):
             if current_pattern is not None:
                 block = dict()
                 block["type"] = "final"
-                block["pattern"] = current_pattern
+                block["pattern"] = (current_pattern, current_subpattern)
                 blocks.append(block)
             line = line.split()
             assert len(line) == 2
             assert line[1] not in patterns
             current_pattern = line[1]
+            current_subpattern = ""
             patterns[current_pattern] = len(blocks)
+            subpatterns[(current_pattern, current_subpattern)] = len(blocks)
+            subpattern_args[(current_pattern, current_subpattern)] = list()
             state_types[current_pattern] = dict()
             udata_types[current_pattern] = dict()
             continue
 
         assert current_pattern is not None
 
+        if cmd == "fallthrough":
+            block = dict()
+            block["type"] = "fallthrough"
+            blocks.append(block)
+            line = line.split()
+            assert len(line) == 1
+            continue
+
+        if cmd == "subpattern":
+            if len(blocks) == 0 or blocks[-1]["type"] != "fallthrough":
+                block = dict()
+                block["type"] = "final"
+                block["pattern"] = (current_pattern, current_subpattern)
+                blocks.append(block)
+            elif len(blocks) and blocks[-1]["type"] == "fallthrough":
+                del blocks[-1]
+            line = line.split()
+            assert len(line) == 2
+            current_subpattern = line[1]
+            subpattern_args[(current_pattern, current_subpattern)] = list()
+            assert (current_pattern, current_subpattern) not in subpatterns
+            subpatterns[(current_pattern, current_subpattern)] = len(blocks)
+            continue
+
+        if cmd == "arg":
+            line = line.split()
+            assert len(line) > 1
+            subpattern_args[(current_pattern, current_subpattern)] += line[1:]
+            continue
+
         if cmd == "state":
             m = re.match(r"^state\s+<(.*?)>\s+(([A-Za-z_][A-Za-z_0-9]*\s+)*[A-Za-z_][A-Za-z_0-9]*)\s*$", line)
             assert m
@@ -155,21 +194,28 @@ def process_pmgfile(f):
         if cmd == "match":
             block = dict()
             block["type"] = "match"
-            block["pattern"] = current_pattern
+            block["src"] = "%s:%d" % (filename, linenr)
+            block["pattern"] = (current_pattern, current_subpattern)
+
+            block["genargs"] = None
+            block["gencode"] = None
 
             line = line.split()
             assert len(line) == 2
-            assert line[1] not in state_types[current_pattern]
+            assert (line[1] not in state_types[current_pattern]) or (state_types[current_pattern][line[1]] == "Cell*")
             block["cell"] = line[1]
             state_types[current_pattern][line[1]] = "Cell*";
 
             block["if"] = list()
-            block["select"] = list()
+            block["setup"] = list()
             block["index"] = list()
             block["filter"] = list()
+            block["sets"] = list()
             block["optional"] = False
+            block["semioptional"] = False
 
             while True:
+                linenr += 1
                 l = f.readline()
                 assert l != ""
                 a = l.split()
@@ -183,7 +229,22 @@ def process_pmgfile(f):
 
                 if a[0] == "select":
                     b = l.lstrip()[6:]
-                    block["select"].append(rewrite_cpp(b.strip()))
+                    block["setup"].append(("select", rewrite_cpp(b.strip())))
+                    continue
+
+                if a[0] == "slice":
+                    m = re.match(r"^\s*slice\s+(\S+)\s+(.*?)\s*$", l)
+                    block["setup"].append(("slice", m.group(1), rewrite_cpp(m.group(2))))
+                    continue
+
+                if a[0] == "choice":
+                    m = re.match(r"^\s*choice\s+<(.*?)>\s+(\S+)\s+(.*?)\s*$", l)
+                    block["setup"].append(("choice", m.group(1), m.group(2), rewrite_cpp(m.group(3))))
+                    continue
+
+                if a[0] == "define":
+                    m = re.match(r"^\s*define\s+<(.*?)>\s+(\S+)\s+(.*?)\s*$", l)
+                    block["setup"].append(("define", m.group(1), m.group(2), rewrite_cpp(m.group(3))))
                     continue
 
                 if a[0] == "index":
@@ -197,35 +258,71 @@ def process_pmgfile(f):
                     block["filter"].append(rewrite_cpp(b.strip()))
                     continue
 
+                if a[0] == "set":
+                    m = re.match(r"^\s*set\s+(\S+)\s+(.*?)\s*$", l)
+                    block["sets"].append((m.group(1), rewrite_cpp(m.group(2))))
+                    continue
+
                 if a[0] == "optional":
                     block["optional"] = True
                     continue
 
+                if a[0] == "semioptional":
+                    block["semioptional"] = True
+                    continue
+
+                if a[0] == "generate":
+                    block["genargs"] = list([int(s) for s in a[1:]])
+                    if len(block["genargs"]) == 0: block["genargs"].append(100)
+                    if len(block["genargs"]) == 1: block["genargs"].append(0)
+                    assert len(block["genargs"]) == 2
+                    block["gencode"] = list()
+                    while True:
+                        linenr += 1
+                        l = f.readline()
+                        assert l != ""
+                        a = l.split()
+                        if len(a) == 1 and a[0] == "endmatch": break
+                        block["gencode"].append(rewrite_cpp(l.rstrip()))
+                    break
+
                 assert False
 
+            if block["optional"]:
+                assert not block["semioptional"]
+
             blocks.append(block)
             continue
 
         if cmd == "code":
             block = dict()
             block["type"] = "code"
-            block["pattern"] = current_pattern
+            block["src"] = "%s:%d" % (filename, linenr)
+            block["pattern"] = (current_pattern, current_subpattern)
 
             block["code"] = list()
+            block["fcode"] = list()
             block["states"] = set()
 
             for s in line.split()[1:]:
                 assert s in state_types[current_pattern]
                 block["states"].add(s)
 
+            codetype = "code"
+
             while True:
+                linenr += 1
                 l = f.readline()
                 assert l != ""
                 a = l.split()
                 if len(a) == 0: continue
                 if a[0] == "endcode": break
 
-                block["code"].append(rewrite_cpp(l.rstrip()))
+                if a[0] == "finally":
+                    codetype = "fcode"
+                    continue
+
+                block[codetype].append(rewrite_cpp(l.rstrip()))
 
             blocks.append(block)
             continue
@@ -234,15 +331,16 @@ def process_pmgfile(f):
 
 for fn in pmgfiles:
     with open(fn, "r") as f:
-        process_pmgfile(f)
+        process_pmgfile(f, fn)
 
 if current_pattern is not None:
     block = dict()
     block["type"] = "final"
-    block["pattern"] = current_pattern
+    block["pattern"] = (current_pattern, current_subpattern)
     blocks.append(block)
 
 current_pattern = None
+current_subpattern = None
 
 if debug:
     pp.pprint(blocks)
@@ -262,7 +360,18 @@ with open(outfile, "w") as f:
     print("struct {}_pm {{".format(prefix), file=f)
     print("  Module *module;", file=f)
     print("  SigMap sigmap;", file=f)
-    print("  std::function<void()> on_accept;".format(prefix), file=f)
+    print("  std::function<void()> on_accept;", file=f)
+    print("  bool generate_mode;", file=f)
+    print("  int accept_cnt;", file=f)
+    print("", file=f)
+
+    print("  uint32_t rngseed;", file=f)
+    print("  int rng(unsigned int n) {", file=f)
+    print("    rngseed ^= rngseed << 13;", file=f)
+    print("    rngseed ^= rngseed >> 17;", file=f)
+    print("    rngseed ^= rngseed << 5;", file=f)
+    print("    return rngseed % n;", file=f)
+    print("  }", file=f)
     print("", file=f)
 
     for index in range(len(blocks)):
@@ -271,12 +380,21 @@ with open(outfile, "w") as f:
             index_types = list()
             for entry in block["index"]:
                 index_types.append(entry[0])
+            value_types = ["Cell*"]
+            for entry in block["setup"]:
+                if entry[0] == "slice":
+                    value_types.append("int")
+                if entry[0] == "choice":
+                    value_types.append(entry[1])
+                if entry[0] == "define":
+                    value_types.append(entry[1])
             print("  typedef std::tuple<{}> index_{}_key_type;".format(", ".join(index_types), index), file=f)
-            print("  dict<index_{}_key_type, vector<Cell*>> index_{};".format(index, index), file=f)
+            print("  typedef std::tuple<{}> index_{}_value_type;".format(", ".join(value_types), index), file=f)
+            print("  dict<index_{}_key_type, vector<index_{}_value_type>> index_{};".format(index, index, index), file=f)
     print("  dict<SigBit, pool<Cell*>> sigusers;", file=f)
     print("  pool<Cell*> blacklist_cells;", file=f)
     print("  pool<Cell*> autoremove_cells;", file=f)
-    print("  bool blacklist_dirty;", file=f)
+    print("  dict<Cell*,int> rollback_cache;", file=f)
     print("  int rollback;", file=f)
     print("", file=f)
 
@@ -304,47 +422,30 @@ with open(outfile, "w") as f:
     print("  void add_siguser(const SigSpec &sig, Cell *cell) {", file=f)
     print("    for (auto bit : sigmap(sig)) {", file=f)
     print("      if (bit.wire == nullptr) continue;", file=f)
-    print("      if (sigusers.count(bit) == 0 && bit.wire->port_id)", file=f)
-    print("        sigusers[bit].insert(nullptr);", file=f)
     print("      sigusers[bit].insert(cell);", file=f)
     print("    }", file=f)
     print("  }", file=f)
     print("", file=f)
 
     print("  void blacklist(Cell *cell) {", file=f)
-    print("    if (cell != nullptr) {", file=f)
-    print("      if (blacklist_cells.insert(cell).second)", file=f)
-    print("        blacklist_dirty = true;", file=f)
+    print("    if (cell != nullptr && blacklist_cells.insert(cell).second) {", file=f)
+    print("      auto ptr = rollback_cache.find(cell);", file=f)
+    print("      if (ptr == rollback_cache.end()) return;", file=f)
+    print("      int rb = ptr->second;", file=f)
+    print("      if (rollback == 0 || rollback > rb)", file=f)
+    print("        rollback = rb;", file=f)
     print("    }", file=f)
     print("  }", file=f)
     print("", file=f)
 
     print("  void autoremove(Cell *cell) {", file=f)
     print("    if (cell != nullptr) {", file=f)
-    print("      if (blacklist_cells.insert(cell).second)", file=f)
-    print("        blacklist_dirty = true;", file=f)
     print("      autoremove_cells.insert(cell);", file=f)
+    print("      blacklist(cell);", file=f)
     print("    }", file=f)
     print("  }", file=f)
     print("", file=f)
 
-    for current_pattern in sorted(patterns.keys()):
-        print("  void check_blacklist_{}() {{".format(current_pattern), file=f)
-        print("    if (!blacklist_dirty)", file=f)
-        print("      return;", file=f)
-        print("    blacklist_dirty = false;", file=f)
-        for index in range(len(blocks)):
-            block = blocks[index]
-            if block["pattern"] != current_pattern:
-                continue
-            if block["type"] == "match":
-                print("    if (st_{}.{} != nullptr && blacklist_cells.count(st_{}.{})) {{".format(current_pattern, block["cell"], current_pattern, block["cell"]), file=f)
-                print("      rollback = {};".format(index+1), file=f)
-                print("      return;", file=f)
-                print("    }", file=f)
-        print("    rollback = 0;", file=f)
-        print("  }", file=f)
-        print("", file=f)
     current_pattern = None
 
     print("  SigSpec port(Cell *cell, IdString portname) {", file=f)
@@ -367,7 +468,7 @@ with open(outfile, "w") as f:
     print("", file=f)
 
     print("  {}_pm(Module *module, const vector<Cell*> &cells) :".format(prefix), file=f)
-    print("      module(module), sigmap(module) {", file=f)
+    print("      module(module), sigmap(module), generate_mode(false), rngseed(12345678) {", file=f)
     for current_pattern in sorted(patterns.keys()):
         for s, t in sorted(udata_types[current_pattern].items()):
             if t.endswith("*"):
@@ -375,10 +476,11 @@ with open(outfile, "w") as f:
             else:
                 print("    ud_{}.{} = {}();".format(current_pattern, s, t), file=f)
     current_pattern = None
-    print("    for (auto cell : module->cells()) {", file=f)
+    print("    for (auto port : module->ports)", file=f)
+    print("      add_siguser(module->wire(port), nullptr);", file=f)
+    print("    for (auto cell : module->cells())", file=f)
     print("      for (auto &conn : cell->connections())", file=f)
     print("        add_siguser(conn.second, cell);", file=f)
-    print("    }", file=f)
     print("    for (auto cell : cells) {", file=f)
 
     for index in range(len(blocks)):
@@ -386,12 +488,34 @@ with open(outfile, "w") as f:
         if block["type"] == "match":
             print("      do {", file=f)
             print("        Cell *{} = cell;".format(block["cell"]), file=f)
-            for expr in block["select"]:
-                print("        if (!({})) break;".format(expr), file=f)
+            print("        index_{}_value_type value;".format(index), file=f)
+            print("        std::get<0>(value) = cell;", file=f)
+            loopcnt = 0
+            valueidx = 1
+            for item in block["setup"]:
+                if item[0] == "select":
+                    print("        if (!({})) continue;".format(item[1]), file=f)
+                if item[0] == "slice":
+                    print("        int &{} = std::get<{}>(value);".format(item[1], valueidx), file=f)
+                    print("        for ({} = 0; {} < {}; {}++) {{".format(item[1], item[1], item[2], item[1]), file=f)
+                    valueidx += 1
+                    loopcnt += 1
+                if item[0] == "choice":
+                    print("        vector<{}> _pmg_choices_{} = {};".format(item[1], item[2], item[3]), file=f)
+                    print("        for (const {} &{} : _pmg_choices_{}) {{".format(item[1], item[2], item[2]), file=f)
+                    print("        std::get<{}>(value) = {};".format(valueidx, item[2]), file=f)
+                    valueidx += 1
+                    loopcnt += 1
+                if item[0] == "define":
+                    print("        {} &{} = std::get<{}>(value);".format(item[1], item[2], valueidx), file=f)
+                    print("        {} = {};".format(item[2], item[3]), file=f)
+                    valueidx += 1
             print("        index_{}_key_type key;".format(index), file=f)
             for field, entry in enumerate(block["index"]):
                 print("        std::get<{}>(key) = {};".format(field, entry[1]), file=f)
-            print("        index_{}[key].push_back(cell);".format(index), file=f)
+            print("        index_{}[key].push_back(value);".format(index), file=f)
+            for i in range(loopcnt):
+                print("        }", file=f)
             print("      } while (0);", file=f)
 
     print("    }", file=f)
@@ -405,41 +529,47 @@ with open(outfile, "w") as f:
     print("", file=f)
 
     for current_pattern in sorted(patterns.keys()):
-        print("  void run_{}(std::function<void()> on_accept_f) {{".format(current_pattern), file=f)
+        print("  int run_{}(std::function<void()> on_accept_f) {{".format(current_pattern), file=f)
+        print("    accept_cnt = 0;", file=f)
         print("    on_accept = on_accept_f;", file=f)
         print("    rollback = 0;", file=f)
-        print("    blacklist_dirty = false;", file=f)
         for s, t in sorted(state_types[current_pattern].items()):
             if t.endswith("*"):
                 print("    st_{}.{} = nullptr;".format(current_pattern, s), file=f)
             else:
                 print("    st_{}.{} = {}();".format(current_pattern, s, t), file=f)
-        print("    block_{}();".format(patterns[current_pattern]), file=f)
+        print("    block_{}(1);".format(patterns[current_pattern]), file=f)
+        print("    log_assert(rollback_cache.empty());", file=f)
+        print("    return accept_cnt;", file=f)
         print("  }", file=f)
         print("", file=f)
-        print("  void run_{}(std::function<void({}_pm&)> on_accept_f) {{".format(current_pattern, prefix), file=f)
-        print("    run_{}([&](){{on_accept_f(*this);}});".format(current_pattern), file=f)
+        print("  int run_{}(std::function<void({}_pm&)> on_accept_f) {{".format(current_pattern, prefix), file=f)
+        print("    return run_{}([&](){{on_accept_f(*this);}});".format(current_pattern), file=f)
         print("  }", file=f)
         print("", file=f)
-        print("  void run_{}(std::function<void(state_{}_t&)> on_accept_f) {{".format(current_pattern, current_pattern), file=f)
-        print("    run_{}([&](){{on_accept_f(st_{});}});".format(current_pattern, current_pattern), file=f)
+        print("  int run_{}() {{".format(current_pattern), file=f)
+        print("    return run_{}([](){{}});".format(current_pattern, current_pattern), file=f)
         print("  }", file=f)
         print("", file=f)
-        print("  void run_{}() {{".format(current_pattern), file=f)
-        print("    run_{}([](){{}});".format(current_pattern, current_pattern), file=f)
-        print("  }", file=f)
+
+    if len(subpatterns):
+        for p, s in sorted(subpatterns.keys()):
+            print("  void block_subpattern_{}_{}(int recursion) {{ block_{}(recursion); }}".format(p, s, subpatterns[(p, s)]), file=f)
         print("", file=f)
+
     current_pattern = None
+    current_subpattern = None
 
     for index in range(len(blocks)):
         block = blocks[index]
 
-        print("  void block_{}() {{".format(index), file=f)
-        current_pattern = block["pattern"]
+        if block["type"] in ("match", "code"):
+            print("  // {}".format(block["src"]), file=f)
+
+        print("  void block_{}(int recursion YS_ATTRIBUTE(unused)) {{".format(index), file=f)
+        current_pattern, current_subpattern = block["pattern"]
 
         if block["type"] == "final":
-            print("    on_accept();", file=f)
-            print("    check_blacklist_{}();".format(current_pattern), file=f)
             print("  }", file=f)
             if index+1 != len(blocks):
                 print("", file=f)
@@ -449,12 +579,17 @@ with open(outfile, "w") as f:
         nonconst_st = set()
         restore_st = set()
 
-        for i in range(patterns[current_pattern], index):
+        for s in subpattern_args[(current_pattern, current_subpattern)]:
+            const_st.add(s)
+
+        for i in range(subpatterns[(current_pattern, current_subpattern)], index):
             if blocks[i]["type"] == "code":
                 for s in blocks[i]["states"]:
                     const_st.add(s)
             elif blocks[i]["type"] == "match":
                 const_st.add(blocks[i]["cell"])
+                for item in blocks[i]["sets"]:
+                    const_st.add(item[0])
             else:
                 assert False
 
@@ -468,6 +603,10 @@ with open(outfile, "w") as f:
             s = block["cell"]
             assert s not in const_st
             nonconst_st.add(s)
+            for item in block["sets"]:
+                if item[0] in const_st:
+                    const_st.remove(item[0])
+                nonconst_st.add(item[0])
         else:
             assert False
 
@@ -482,37 +621,55 @@ with open(outfile, "w") as f:
             t = state_types[current_pattern][s]
             print("    {} &{} YS_ATTRIBUTE(unused) = st_{}.{};".format(t, s, current_pattern, s), file=f)
 
+        for u in sorted(udata_types[current_pattern].keys()):
+            t = udata_types[current_pattern][u]
+            print("    {} &{} YS_ATTRIBUTE(unused) = ud_{}.{};".format(t, u, current_pattern, u), file=f)
+
         if len(restore_st):
             print("", file=f)
             for s in sorted(restore_st):
                 t = state_types[current_pattern][s]
-                print("    {} backup_{} = {};".format(t, s, s), file=f)
+                print("    {} _pmg_backup_{} = {};".format(t, s, s), file=f)
 
         if block["type"] == "code":
             print("", file=f)
-            print("    do {", file=f)
-            print("#define reject do {{ check_blacklist_{}(); goto rollback_label; }} while(0)".format(current_pattern), file=f)
-            print("#define accept do {{ on_accept(); check_blacklist_{}(); if (rollback) goto rollback_label; }} while(0)".format(current_pattern), file=f)
-            print("#define branch do {{ block_{}(); if (rollback) goto rollback_label; }} while(0)".format(index+1), file=f)
+            print("#define reject do { goto rollback_label; } while(0)", file=f)
+            print("#define accept do { accept_cnt++; on_accept(); if (rollback) goto rollback_label; } while(0)", file=f)
+            print("#define finish do { rollback = -1; goto rollback_label; } while(0)", file=f)
+            print("#define branch do {{ block_{}(recursion+1); if (rollback) goto rollback_label; }} while(0)".format(index+1), file=f)
+            print("#define subpattern(pattern_name) do {{ block_subpattern_{}_ ## pattern_name (recursion+1); if (rollback) goto rollback_label; }} while(0)".format(current_pattern), file=f)
 
             for line in block["code"]:
-                print("    " + line, file=f)
+                print("  " + line, file=f)
 
             print("", file=f)
-            print("      block_{}();".format(index+1), file=f)
+            print("    block_{}(recursion+1);".format(index+1), file=f)
+
             print("#undef reject", file=f)
             print("#undef accept", file=f)
+            print("#undef finish", file=f)
             print("#undef branch", file=f)
-            print("    } while (0);", file=f)
+            print("#undef subpattern", file=f)
+
             print("", file=f)
             print("rollback_label:", file=f)
             print("    YS_ATTRIBUTE(unused);", file=f)
 
+            if len(block["fcode"]):
+                print("#define accept do { accept_cnt++; on_accept(); } while(0)", file=f)
+                print("#define finish do { rollback = -1; goto finish_label; } while(0)", file=f)
+                for line in block["fcode"]:
+                    print("  " + line, file=f)
+                print("finish_label:", file=f)
+                print("    YS_ATTRIBUTE(unused);", file=f)
+                print("#undef accept", file=f)
+                print("#undef finish", file=f)
+
             if len(restore_st) or len(nonconst_st):
                 print("", file=f)
                 for s in sorted(restore_st):
                     t = state_types[current_pattern][s]
-                    print("    {} = backup_{};".format(s, s), file=f)
+                    print("    {} = _pmg_backup_{};".format(s, s), file=f)
                 for s in sorted(nonconst_st):
                     if s not in restore_st:
                         t = state_types[current_pattern][s]
@@ -524,12 +681,15 @@ with open(outfile, "w") as f:
         elif block["type"] == "match":
             assert len(restore_st) == 0
 
+            print("    Cell* _pmg_backup_{} = {};".format(block["cell"], block["cell"]), file=f)
+
             if len(block["if"]):
                 for expr in block["if"]:
                     print("", file=f)
                     print("    if (!({})) {{".format(expr), file=f)
                     print("      {} = nullptr;".format(block["cell"]), file=f)
-                    print("      block_{}();".format(index+1), file=f)
+                    print("      block_{}(recursion+1);".format(index+1), file=f)
+                    print("      {} = _pmg_backup_{};".format(block["cell"], block["cell"]), file=f)
                     print("      return;", file=f)
                     print("    }", file=f)
 
@@ -537,21 +697,48 @@ with open(outfile, "w") as f:
             print("    index_{}_key_type key;".format(index), file=f)
             for field, entry in enumerate(block["index"]):
                 print("    std::get<{}>(key) = {};".format(field, entry[2]), file=f)
-            print("    const vector<Cell*> &cells = index_{}[key];".format(index), file=f)
+            print("    auto cells_ptr = index_{}.find(key);".format(index), file=f)
+
+            if block["semioptional"] or block["genargs"] is not None:
+                print("    bool found_any_match = false;", file=f)
 
             print("", file=f)
-            print("    for (int idx = 0; idx < GetSize(cells); idx++) {", file=f)
-            print("      {} = cells[idx];".format(block["cell"]), file=f)
-            print("      if (blacklist_cells.count({})) continue;".format(block["cell"]), file=f)
+            print("    if (cells_ptr != index_{}.end()) {{".format(index), file=f)
+            print("      const vector<index_{}_value_type> &cells = cells_ptr->second;".format(index), file=f)
+            print("      for (int _pmg_idx = 0; _pmg_idx < GetSize(cells); _pmg_idx++) {", file=f)
+            print("        {} = std::get<0>(cells[_pmg_idx]);".format(block["cell"]), file=f)
+            valueidx = 1
+            for item in block["setup"]:
+                if item[0] == "slice":
+                    print("        const int &{} YS_ATTRIBUTE(unused) = std::get<{}>(cells[_pmg_idx]);".format(item[1], valueidx), file=f)
+                    valueidx += 1
+                if item[0] == "choice":
+                    print("        const {} &{} YS_ATTRIBUTE(unused) = std::get<{}>(cells[_pmg_idx]);".format(item[1], item[2], valueidx), file=f)
+                    valueidx += 1
+                if item[0] == "define":
+                    print("        const {} &{} YS_ATTRIBUTE(unused) = std::get<{}>(cells[_pmg_idx]);".format(item[1], item[2], valueidx), file=f)
+                    valueidx += 1
+            print("        if (blacklist_cells.count({})) continue;".format(block["cell"]), file=f)
             for expr in block["filter"]:
-                print("      if (!({})) continue;".format(expr), file=f)
-            print("      block_{}();".format(index+1), file=f)
-            print("      if (rollback) {", file=f)
-            print("        if (rollback != {}) {{".format(index+1), file=f)
-            print("          {} = nullptr;".format(block["cell"]), file=f)
-            print("          return;", file=f)
+                print("        if (!({})) continue;".format(expr), file=f)
+            if block["semioptional"] or block["genargs"] is not None:
+                print("        found_any_match = true;", file=f)
+            for item in block["sets"]:
+                print("        auto _pmg_backup_{} = {};".format(item[0], item[0]), file=f)
+                print("        {} = {};".format(item[0], item[1]), file=f)
+            print("        auto rollback_ptr = rollback_cache.insert(make_pair(std::get<0>(cells[_pmg_idx]), recursion));", file=f)
+            print("        block_{}(recursion+1);".format(index+1), file=f)
+            for item in block["sets"]:
+                print("        {} = _pmg_backup_{};".format(item[0], item[0]), file=f)
+            print("        if (rollback_ptr.second)", file=f)
+            print("          rollback_cache.erase(rollback_ptr.first);", file=f)
+            print("        if (rollback) {", file=f)
+            print("          if (rollback != recursion) {{".format(index+1), file=f)
+            print("            {} = _pmg_backup_{};".format(block["cell"], block["cell"]), file=f)
+            print("            return;", file=f)
+            print("          }", file=f)
+            print("          rollback = 0;", file=f)
             print("        }", file=f)
-            print("        rollback = 0;", file=f)
             print("      }", file=f)
             print("    }", file=f)
 
@@ -559,8 +746,20 @@ with open(outfile, "w") as f:
             print("    {} = nullptr;".format(block["cell"]), file=f)
 
             if block["optional"]:
-                print("    block_{}();".format(index+1), file=f)
+                print("    block_{}(recursion+1);".format(index+1), file=f)
 
+            if block["semioptional"]:
+                print("    if (!found_any_match) block_{}(recursion+1);".format(index+1), file=f)
+
+            print("    {} = _pmg_backup_{};".format(block["cell"], block["cell"]), file=f)
+
+            if block["genargs"] is not None:
+                print("#define finish do { rollback = -1; return; } while(0)", file=f)
+                print("    if (generate_mode && rng(100) < (found_any_match ? {} : {})) {{".format(block["genargs"][1], block["genargs"][0]), file=f)
+                for line in block["gencode"]:
+                    print("      " + line, file=f)
+                print("    }", file=f)
+                print("#undef finish", file=f)
         else:
             assert False
 
diff --git a/passes/pmgen/test_pmgen.cc b/passes/pmgen/test_pmgen.cc
new file mode 100644
index 000000000..0ad769dfd
--- /dev/null
+++ b/passes/pmgen/test_pmgen.cc
@@ -0,0 +1,379 @@
+/*
+ *  yosys -- Yosys Open SYnthesis Suite
+ *
+ *  Copyright (C) 2012  Clifford Wolf <clifford@clifford.at>
+ *
+ *  Permission to use, copy, modify, and/or distribute this software for any
+ *  purpose with or without fee is hereby granted, provided that the above
+ *  copyright notice and this permission notice appear in all copies.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#include "kernel/yosys.h"
+#include "kernel/sigtools.h"
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+// for peepopt_pm
+bool did_something;
+
+#include "passes/pmgen/test_pmgen_pm.h"
+#include "passes/pmgen/ice40_dsp_pm.h"
+#include "passes/pmgen/peepopt_pm.h"
+
+void reduce_chain(test_pmgen_pm &pm)
+{
+	auto &st = pm.st_reduce;
+	auto &ud = pm.ud_reduce;
+
+	if (ud.longest_chain.empty())
+		return;
+
+	log("Found chain of length %d (%s):\n", GetSize(ud.longest_chain), log_id(st.first->type));
+
+	SigSpec A;
+	SigSpec Y = ud.longest_chain.front().first->getPort(ID(Y));
+	auto last_cell = ud.longest_chain.back().first;
+
+	for (auto it : ud.longest_chain) {
+		auto cell = it.first;
+		if (cell == last_cell) {
+			A.append(cell->getPort(ID(A)));
+			A.append(cell->getPort(ID(B)));
+		} else {
+			A.append(cell->getPort(it.second == ID(A) ? ID(B) : ID(A)));
+		}
+		log("    %s\n", log_id(cell));
+		pm.autoremove(cell);
+	}
+
+	Cell *c;
+
+	if (last_cell->type == ID($_AND_))
+		c = pm.module->addReduceAnd(NEW_ID, A, Y);
+	else if (last_cell->type == ID($_OR_))
+		c = pm.module->addReduceOr(NEW_ID, A, Y);
+	else if (last_cell->type == ID($_XOR_))
+		c = pm.module->addReduceXor(NEW_ID, A, Y);
+	else
+		log_abort();
+
+	log("    -> %s (%s)\n", log_id(c), log_id(c->type));
+}
+
+void reduce_tree(test_pmgen_pm &pm)
+{
+	auto &st = pm.st_reduce;
+	auto &ud = pm.ud_reduce;
+
+	if (ud.longest_chain.empty())
+		return;
+
+	SigSpec A = ud.leaves;
+	SigSpec Y = st.first->getPort(ID(Y));
+	pm.autoremove(st.first);
+
+	log("Found %s tree with %d leaves for %s (%s).\n", log_id(st.first->type),
+			GetSize(A), log_signal(Y), log_id(st.first));
+
+	Cell *c;
+
+	if (st.first->type == ID($_AND_))
+		c = pm.module->addReduceAnd(NEW_ID, A, Y);
+	else if (st.first->type == ID($_OR_))
+		c = pm.module->addReduceOr(NEW_ID, A, Y);
+	else if (st.first->type == ID($_XOR_))
+		c = pm.module->addReduceXor(NEW_ID, A, Y);
+	else
+		log_abort();
+
+	log("    -> %s (%s)\n", log_id(c), log_id(c->type));
+}
+
+void opt_eqpmux(test_pmgen_pm &pm)
+{
+	auto &st = pm.st_eqpmux;
+
+	SigSpec Y = st.pmux->getPort(ID::Y);
+	int width = GetSize(Y);
+
+	SigSpec EQ = st.pmux->getPort(ID::B).extract(st.pmux_slice_eq*width, width);
+	SigSpec NE = st.pmux->getPort(ID::B).extract(st.pmux_slice_ne*width, width);
+
+	log("Found eqpmux circuit driving %s (eq=%s, ne=%s, pmux=%s).\n",
+			log_signal(Y), log_id(st.eq), log_id(st.ne), log_id(st.pmux));
+
+	pm.autoremove(st.pmux);
+	Cell *c = pm.module->addMux(NEW_ID, NE, EQ, st.eq->getPort(ID::Y), Y);
+	log("    -> %s (%s)\n", log_id(c), log_id(c->type));
+}
+
+#define GENERATE_PATTERN(pmclass, pattern) \
+	generate_pattern<pmclass>([](pmclass &pm, std::function<void()> f){ return pm.run_ ## pattern(f); }, #pmclass, #pattern, design)
+
+void pmtest_addports(Module *module)
+{
+	pool<SigBit> driven_bits, used_bits;
+	SigMap sigmap(module);
+	int icnt = 0, ocnt = 0;
+
+	for (auto cell : module->cells())
+	for (auto conn : cell->connections())
+	{
+		if (cell->input(conn.first))
+			for (auto bit : sigmap(conn.second))
+				used_bits.insert(bit);
+		if (cell->output(conn.first))
+			for (auto bit : sigmap(conn.second))
+				driven_bits.insert(bit);
+	}
+
+	for (auto wire : vector<Wire*>(module->wires()))
+	{
+		SigSpec ibits, obits;
+		for (auto bit : sigmap(wire)) {
+			if (!used_bits.count(bit))
+				obits.append(bit);
+			if (!driven_bits.count(bit))
+				ibits.append(bit);
+		}
+		if (!ibits.empty()) {
+			Wire *w = module->addWire(stringf("\\i%d", icnt++), GetSize(ibits));
+			w->port_input = true;
+			module->connect(ibits, w);
+		}
+		if (!obits.empty()) {
+			Wire *w = module->addWire(stringf("\\o%d", ocnt++), GetSize(obits));
+			w->port_output = true;
+			module->connect(w, obits);
+		}
+	}
+
+	module->fixup_ports();
+}
+
+template <class pm>
+void generate_pattern(std::function<void(pm&,std::function<void()>)> run, const char *pmclass, const char *pattern, Design *design)
+{
+	log("Generating \"%s\" patterns for pattern matcher \"%s\".\n", pattern, pmclass);
+
+	int modcnt = 0;
+	int maxmodcnt = 100;
+	int maxsubcnt = 4;
+	int timeout = 0;
+	vector<Module*> mods;
+
+	while (modcnt < maxmodcnt)
+	{
+		int submodcnt = 0, itercnt = 0, cellcnt = 0;
+		Module *mod = design->addModule(NEW_ID);
+
+		while (modcnt < maxmodcnt && submodcnt < maxsubcnt && itercnt++ < 1000)
+		{
+			if (timeout++ > 10000)
+				log_error("pmgen generator is stuck: 10000 iterations an no matching module generated.\n");
+
+			pm matcher(mod, mod->cells());
+
+			matcher.rng(1);
+			matcher.rngseed += modcnt;
+			matcher.rng(1);
+			matcher.rngseed += submodcnt;
+			matcher.rng(1);
+			matcher.rngseed += itercnt;
+			matcher.rng(1);
+			matcher.rngseed += cellcnt;
+			matcher.rng(1);
+
+			if (GetSize(mod->cells()) != cellcnt)
+			{
+				bool found_match = false;
+				run(matcher, [&](){ found_match = true; });
+				cellcnt = GetSize(mod->cells());
+
+				if (found_match) {
+					Module *m = design->addModule(stringf("\\pmtest_%s_%s_%05d",
+							pmclass, pattern, modcnt++));
+					log("Creating module %s with %d cells.\n", log_id(m), cellcnt);
+					mod->cloneInto(m);
+					pmtest_addports(m);
+					mods.push_back(m);
+					submodcnt++;
+					timeout = 0;
+				}
+			}
+
+			matcher.generate_mode = true;
+			run(matcher, [](){});
+		}
+
+		if (submodcnt)
+			maxsubcnt *= 2;
+
+		design->remove(mod);
+	}
+
+	Module *m = design->addModule(stringf("\\pmtest_%s_%s", pmclass, pattern));
+	log("Creating module %s with %d cells.\n", log_id(m), GetSize(mods));
+	for (auto mod : mods) {
+		Cell *c = m->addCell(mod->name, mod->name);
+		for (auto port : mod->ports) {
+			Wire *w = m->addWire(NEW_ID, GetSize(mod->wire(port)));
+			c->setPort(port, w);
+		}
+	}
+	pmtest_addports(m);
+}
+
+struct TestPmgenPass : public Pass {
+	TestPmgenPass() : Pass("test_pmgen", "test pass for pmgen") { }
+	void help() YS_OVERRIDE
+	{
+		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+		log("\n");
+		log("    test_pmgen -reduce_chain [options] [selection]\n");
+		log("\n");
+		log("Demo for recursive pmgen patterns. Map chains of AND/OR/XOR to $reduce_*.\n");
+		log("\n");
+
+		log("\n");
+		log("    test_pmgen -reduce_tree [options] [selection]\n");
+		log("\n");
+		log("Demo for recursive pmgen patterns. Map trees of AND/OR/XOR to $reduce_*.\n");
+		log("\n");
+
+		log("\n");
+		log("    test_pmgen -eqpmux [options] [selection]\n");
+		log("\n");
+		log("Demo for recursive pmgen patterns. Optimize EQ/NE/PMUX circuits.\n");
+		log("\n");
+
+		log("\n");
+		log("    test_pmgen -generate [options] <pattern_name>\n");
+		log("\n");
+		log("Create modules that match the specified pattern.\n");
+		log("\n");
+	}
+
+	void execute_reduce_chain(std::vector<std::string> args, RTLIL::Design *design)
+	{
+		log_header(design, "Executing TEST_PMGEN pass (-reduce_chain).\n");
+
+		size_t argidx;
+		for (argidx = 2; argidx < args.size(); argidx++)
+		{
+			// if (args[argidx] == "-singleton") {
+			// 	singleton_mode = true;
+			// 	continue;
+			// }
+			break;
+		}
+		extra_args(args, argidx, design);
+
+		for (auto module : design->selected_modules())
+			while (test_pmgen_pm(module, module->selected_cells()).run_reduce(reduce_chain)) {}
+	}
+
+	void execute_reduce_tree(std::vector<std::string> args, RTLIL::Design *design)
+	{
+		log_header(design, "Executing TEST_PMGEN pass (-reduce_tree).\n");
+
+		size_t argidx;
+		for (argidx = 2; argidx < args.size(); argidx++)
+		{
+			// if (args[argidx] == "-singleton") {
+			// 	singleton_mode = true;
+			// 	continue;
+			// }
+			break;
+		}
+		extra_args(args, argidx, design);
+
+		for (auto module : design->selected_modules())
+			test_pmgen_pm(module, module->selected_cells()).run_reduce(reduce_tree);
+	}
+
+	void execute_eqpmux(std::vector<std::string> args, RTLIL::Design *design)
+	{
+		log_header(design, "Executing TEST_PMGEN pass (-eqpmux).\n");
+
+		size_t argidx;
+		for (argidx = 2; argidx < args.size(); argidx++)
+		{
+			// if (args[argidx] == "-singleton") {
+			// 	singleton_mode = true;
+			// 	continue;
+			// }
+			break;
+		}
+		extra_args(args, argidx, design);
+
+		for (auto module : design->selected_modules())
+			test_pmgen_pm(module, module->selected_cells()).run_eqpmux(opt_eqpmux);
+	}
+
+	void execute_generate(std::vector<std::string> args, RTLIL::Design *design)
+	{
+		log_header(design, "Executing TEST_PMGEN pass (-generate).\n");
+
+		size_t argidx;
+		for (argidx = 2; argidx < args.size(); argidx++)
+		{
+			// if (args[argidx] == "-singleton") {
+			// 	singleton_mode = true;
+			// 	continue;
+			// }
+			break;
+		}
+
+		if (argidx+1 != args.size())
+			log_cmd_error("Expected exactly one pattern.\n");
+
+		string pattern = args[argidx];
+
+		if (pattern == "reduce")
+			return GENERATE_PATTERN(test_pmgen_pm, reduce);
+
+		if (pattern == "eqpmux")
+			return GENERATE_PATTERN(test_pmgen_pm, eqpmux);
+
+		if (pattern == "ice40_dsp")
+			return GENERATE_PATTERN(ice40_dsp_pm, ice40_dsp);
+
+		if (pattern == "peepopt-muldiv")
+			return GENERATE_PATTERN(peepopt_pm, muldiv);
+
+		if (pattern == "peepopt-shiftmul")
+			return GENERATE_PATTERN(peepopt_pm, shiftmul);
+
+		log_cmd_error("Unkown pattern: %s\n", pattern.c_str());
+	}
+
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
+	{
+		if (GetSize(args) > 1)
+		{
+			if (args[1] == "-reduce_chain")
+				return execute_reduce_chain(args, design);
+			if (args[1] == "-reduce_tree")
+				return execute_reduce_tree(args, design);
+			if (args[1] == "-eqpmux")
+				return execute_eqpmux(args, design);
+			if (args[1] == "-generate")
+				return execute_generate(args, design);
+		}
+		help();
+		log_cmd_error("Missing or unsupported mode parameter.\n");
+	}
+} TestPmgenPass;
+
+PRIVATE_NAMESPACE_END
diff --git a/passes/pmgen/test_pmgen.pmg b/passes/pmgen/test_pmgen.pmg
new file mode 100644
index 000000000..287ed97d8
--- /dev/null
+++ b/passes/pmgen/test_pmgen.pmg
@@ -0,0 +1,189 @@
+pattern reduce
+
+state <IdString> portname
+udata <vector<pair<Cell*, IdString>>> chain longest_chain
+udata <pool<Cell*>> non_first_cells
+udata <SigSpec> leaves
+
+code
+	non_first_cells.clear();
+	subpattern(setup);
+endcode
+
+match first
+	select first->type.in($_AND_, $_OR_, $_XOR_)
+	filter !non_first_cells.count(first)
+generate
+	SigSpec A = module->addWire(NEW_ID);
+	SigSpec B = module->addWire(NEW_ID);
+	SigSpec Y = module->addWire(NEW_ID);
+	switch (rng(3))
+	{
+	case 0:
+		module->addAndGate(NEW_ID, A, B, Y);
+		break;
+	case 1:
+		module->addOrGate(NEW_ID, A, B, Y);
+		break;
+	case 2:
+		module->addXorGate(NEW_ID, A, B, Y);
+		break;
+	}
+endmatch
+
+code
+	leaves = SigSpec();
+	longest_chain.clear();
+	chain.push_back(make_pair(first, \A));
+	subpattern(tail);
+	chain.back().second = \B;
+	subpattern(tail);
+finally
+	chain.pop_back();
+	log_assert(chain.empty());
+	if (GetSize(longest_chain) > 1)
+		accept;
+endcode
+
+// ------------------------------------------------------------------
+
+subpattern setup
+
+match first
+	select first->type.in($_AND_, $_OR_, $_XOR_)
+endmatch
+
+code portname
+	portname = \A;
+	branch;
+	portname = \B;
+endcode
+
+match next
+	select next->type.in($_AND_, $_OR_, $_XOR_)
+	select nusers(port(next, \Y)) == 2
+	index <IdString> next->type === first->type
+	index <SigSpec> port(next, \Y) === port(first, portname)
+endmatch
+
+code
+	non_first_cells.insert(next);
+endcode
+
+// ------------------------------------------------------------------
+
+subpattern tail
+arg first
+
+match next
+	semioptional
+	select next->type.in($_AND_, $_OR_, $_XOR_)
+	select nusers(port(next, \Y)) == 2
+	index <IdString> next->type === chain.back().first->type
+	index <SigSpec> port(next, \Y) === port(chain.back().first, chain.back().second)
+generate 10
+	SigSpec A = module->addWire(NEW_ID);
+	SigSpec B = module->addWire(NEW_ID);
+	SigSpec Y = port(chain.back().first, chain.back().second);
+	Cell *c = module->addAndGate(NEW_ID, A, B, Y);
+	c->type = chain.back().first->type;
+endmatch
+
+code
+	if (next) {
+		chain.push_back(make_pair(next, \A));
+		subpattern(tail);
+		chain.back().second = \B;
+		subpattern(tail);
+	} else {
+		if (GetSize(chain) > GetSize(longest_chain))
+			longest_chain = chain;
+		leaves.append(port(chain.back().first, chain.back().second));
+	}
+finally
+	if (next)
+		chain.pop_back();
+endcode
+
+// ==================================================================
+
+pattern eqpmux
+
+state <bool> eq_ne_signed
+state <SigSpec> eq_inA eq_inB
+state <int> pmux_slice_eq pmux_slice_ne
+
+match eq
+	select eq->type == $eq
+	choice <IdString> AB {\A, \B}
+	define <IdString> BA AB == \A ? \B : \A
+	set eq_inA port(eq, \A)
+	set eq_inB port(eq, \B)
+	set eq_ne_signed param(eq, \A_SIGNED).as_bool()
+generate 100 10
+	SigSpec A = module->addWire(NEW_ID, rng(7)+1);
+	SigSpec B = module->addWire(NEW_ID, rng(7)+1);
+	SigSpec Y = module->addWire(NEW_ID);
+	module->addEq(NEW_ID, A, B, Y, rng(2));
+endmatch
+
+match pmux
+	select pmux->type == $pmux
+	slice idx GetSize(port(pmux, \S))
+	index <SigBit> port(pmux, \S)[idx] === port(eq, \Y)
+	set pmux_slice_eq idx
+generate 100 10
+	int width = rng(7) + 1;
+	int numsel = rng(4) + 1;
+	int idx = rng(numsel);
+
+	SigSpec A = module->addWire(NEW_ID, width);
+	SigSpec Y = module->addWire(NEW_ID, width);
+
+	SigSpec B, S;
+	for (int i = 0; i < numsel; i++) {
+		B.append(module->addWire(NEW_ID, width));
+		S.append(i == idx ? port(eq, \Y) : module->addWire(NEW_ID));
+	}
+
+	module->addPmux(NEW_ID, A, B, S, Y);
+endmatch
+
+match ne
+	select ne->type == $ne
+	choice <IdString> AB {\A, \B}
+	define <IdString> BA (AB == \A ? \B : \A)
+	index <SigSpec> port(ne, AB) === eq_inA
+	index <SigSpec> port(ne, BA) === eq_inB
+	index <int> param(ne, \A_SIGNED).as_bool() === eq_ne_signed
+generate 100 10
+	SigSpec A = eq_inA, B = eq_inB, Y;
+	if (rng(2)) {
+		std::swap(A, B);
+	}
+	if (rng(2)) {
+		for (auto bit : port(pmux, \S)) {
+			if (nusers(bit) < 2)
+				Y.append(bit);
+		}
+		if (GetSize(Y))
+			Y = Y[rng(GetSize(Y))];
+		else
+			Y = module->addWire(NEW_ID);
+	} else {
+		Y = module->addWire(NEW_ID);
+	}
+	module->addNe(NEW_ID, A, B, Y, rng(2));
+endmatch
+
+match pmux2
+	select pmux2->type == $pmux
+	slice idx GetSize(port(pmux2, \S))
+	index <Cell*> pmux2 === pmux
+	index <SigBit> port(pmux2, \S)[idx] === port(ne, \Y)
+	set pmux_slice_ne idx
+endmatch
+
+code
+	accept;
+endcode
diff --git a/passes/sat/async2sync.cc b/passes/sat/async2sync.cc
index d045d0dcb..24ae6e448 100644
--- a/passes/sat/async2sync.cc
+++ b/passes/sat/async2sync.cc
@@ -39,7 +39,7 @@ struct Async2syncPass : public Pass {
 		log("reset value in the next cycle regardless of the data-in value at the time of\n");
 		log("the clock edge.\n");
 		log("\n");
-		log("Currently only $adff and $dffsr cells are supported by this pass.\n");
+		log("Currently only $adff, $dffsr, and $dlatch cells are supported by this pass.\n");
 		log("\n");
 	}
 	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
@@ -169,6 +169,41 @@ struct Async2syncPass : public Pass {
 					cell->type = "$dff";
 					continue;
 				}
+
+				if (cell->type.in("$dlatch"))
+				{
+					bool en_pol = cell->parameters["\\EN_POLARITY"].as_bool();
+
+					SigSpec sig_en = cell->getPort("\\EN");
+					SigSpec sig_d = cell->getPort("\\D");
+					SigSpec sig_q = cell->getPort("\\Q");
+
+					log("Replacing %s.%s (%s): EN=%s, D=%s, Q=%s\n",
+							log_id(module), log_id(cell), log_id(cell->type),
+							log_signal(sig_en), log_signal(sig_d), log_signal(sig_q));
+
+					Const init_val;
+					for (int i = 0; i < GetSize(sig_q); i++) {
+						SigBit bit = sigmap(sig_q[i]);
+						init_val.bits.push_back(initbits.count(bit) ? initbits.at(bit) : State::Sx);
+						del_initbits.insert(bit);
+					}
+
+					Wire *new_q = module->addWire(NEW_ID, GetSize(sig_q));
+					new_q->attributes["\\init"] = init_val;
+
+					if (en_pol) {
+						module->addMux(NEW_ID, new_q, sig_d, sig_en, sig_q);
+					} else {
+						module->addMux(NEW_ID, sig_d, new_q, sig_en, sig_q);
+					}
+
+					cell->setPort("\\Q", new_q);
+					cell->unsetPort("\\EN");
+					cell->unsetParam("\\EN_POLARITY");
+					cell->type = "$ff";
+					continue;
+				}
 			}
 
 			for (auto wire : module->wires())
diff --git a/passes/sat/sat.cc b/passes/sat/sat.cc
index dd56d8c71..430bba1e8 100644
--- a/passes/sat/sat.cc
+++ b/passes/sat/sat.cc
@@ -268,7 +268,7 @@ struct SatHelper
 				RTLIL::SigSpec removed_bits;
 				for (int i = 0; i < lhs.size(); i++) {
 					RTLIL::SigSpec bit = lhs.extract(i, 1);
-					if (!satgen.initial_state.check_all(bit)) {
+					if (rhs[i] == State::Sx || !satgen.initial_state.check_all(bit)) {
 						removed_bits.append(bit);
 						lhs.remove(i, 1);
 						rhs.remove(i, 1);
diff --git a/passes/techmap/Makefile.inc b/passes/techmap/Makefile.inc
index 56f05eca4..631a80aa5 100644
--- a/passes/techmap/Makefile.inc
+++ b/passes/techmap/Makefile.inc
@@ -16,6 +16,7 @@ endif
 
 ifneq ($(SMALL),1)
 OBJS += passes/techmap/iopadmap.o
+OBJS += passes/techmap/clkbufmap.o
 OBJS += passes/techmap/hilomap.o
 OBJS += passes/techmap/extract.o
 OBJS += passes/techmap/extract_fa.o
diff --git a/passes/techmap/abc9.cc b/passes/techmap/abc9.cc
index c1d4fff2d..84cb2c04f 100644
--- a/passes/techmap/abc9.cc
+++ b/passes/techmap/abc9.cc
@@ -76,12 +76,11 @@ inline std::string remap_name(RTLIL::IdString abc_name)
 	return stringf("$abc$%d$%s", map_autoidx, abc_name.c_str()+1);
 }
 
-void handle_loops(RTLIL::Design *design)
+void handle_loops(RTLIL::Design *design,
+		const dict<IdString,pool<IdString>> &scc_break_inputs)
 {
 	Pass::call(design, "scc -set_attr abc_scc_id {}");
 
-	dict<IdString, vector<IdString>> abc_scc_break;
-
 	// For every unique SCC found, (arbitrarily) find the first
 	// cell in the component, and select (and mark) all its output
 	// wires
@@ -116,44 +115,29 @@ void handle_loops(RTLIL::Design *design)
 			cell->attributes.erase(it);
 		}
 
-		auto jt = abc_scc_break.find(cell->type);
-		if (jt == abc_scc_break.end()) {
-			std::vector<IdString> ports;
-			RTLIL::Module* box_module = design->module(cell->type);
-			if (box_module) {
-				auto ports_csv = box_module->attributes.at(ID(abc_scc_break), RTLIL::Const::from_string("")).decode_string();
-				for (const auto &port_name : split_tokens(ports_csv, ",")) {
-					auto port_id = RTLIL::escape_id(port_name);
-					auto kt = cell->connections_.find(port_id);
-					if (kt == cell->connections_.end())
-						log_error("abc_scc_break attribute value '%s' does not exist as port on module '%s'\n", port_name.c_str(), log_id(box_module));
-					ports.push_back(port_id);
-				}
-			}
-			jt = abc_scc_break.insert(std::make_pair(cell->type, std::move(ports))).first;
-		}
-
-		for (auto port_name : jt->second) {
-			RTLIL::SigSpec sig;
-			auto &rhs = cell->connections_.at(port_name);
-			for (auto b : rhs) {
-				Wire *w = b.wire;
-				if (!w) continue;
-				w->port_output = true;
-				w->set_bool_attribute(ID(abc_scc_break));
-				w = module->wire(stringf("%s.abci", w->name.c_str()));
-				if (!w) {
-					w = module->addWire(stringf("%s.abci", b.wire->name.c_str()), GetSize(b.wire));
-					w->port_input = true;
-				}
-				else {
-					log_assert(b.offset < GetSize(w));
-					log_assert(w->port_input);
+		auto jt = scc_break_inputs.find(cell->type);
+		if (jt != scc_break_inputs.end())
+			for (auto port_name : jt->second) {
+				RTLIL::SigSpec sig;
+				auto &rhs = cell->connections_.at(port_name);
+				for (auto b : rhs) {
+					Wire *w = b.wire;
+					if (!w) continue;
+					w->port_output = true;
+					w->set_bool_attribute(ID(abc_scc_break));
+					w = module->wire(stringf("%s.abci", w->name.c_str()));
+					if (!w) {
+						w = module->addWire(stringf("%s.abci", b.wire->name.c_str()), GetSize(b.wire));
+						w->port_input = true;
+					}
+					else {
+						log_assert(b.offset < GetSize(w));
+						log_assert(w->port_input);
+					}
+					sig.append(RTLIL::SigBit(w, b.offset));
 				}
-				sig.append(RTLIL::SigBit(w, b.offset));
+				rhs = sig;
 			}
-			rhs = sig;
-		}
 	}
 
 	module->fixup_ports();
@@ -288,7 +272,9 @@ void abc9_module(RTLIL::Design *design, RTLIL::Module *current_module, std::stri
 		bool cleanup, vector<int> lut_costs, bool dff_mode, std::string clk_str,
 		bool /*keepff*/, std::string delay_target, std::string /*lutin_shared*/, bool fast_mode,
 		bool show_tempdir, std::string box_file, std::string lut_file,
-		std::string wire_delay, const dict<int,IdString> &box_lookup)
+		std::string wire_delay, const dict<int,IdString> &box_lookup,
+		const dict<IdString,pool<IdString>> &scc_break_inputs
+)
 {
 	module = current_module;
 	map_autoidx = autoidx++;
@@ -427,7 +413,7 @@ void abc9_module(RTLIL::Design *design, RTLIL::Module *current_module, std::stri
 		RTLIL::Selection& sel = design->selection_stack.back();
 		sel.select(module);
 
-		handle_loops(design);
+		handle_loops(design, scc_break_inputs);
 
 		Pass::call(design, "aigmap");
 
@@ -1081,6 +1067,7 @@ struct Abc9Pass : public Pass {
 		extra_args(args, argidx, design);
 
 		dict<int,IdString> box_lookup;
+		dict<IdString,pool<IdString>> scc_break_inputs;
 		for (auto m : design->modules()) {
 			auto it = m->attributes.find(ID(abc_box_id));
 			if (it == m->attributes.end())
@@ -1093,6 +1080,56 @@ struct Abc9Pass : public Pass {
 				log_error("Module '%s' has the same abc_box_id = %d value as '%s'.\n",
 						log_id(m), id, log_id(r.first->second));
 			log_assert(r.second);
+
+			RTLIL::Wire *carry_in = nullptr, *carry_out = nullptr;
+			for (auto p : m->ports) {
+				auto w = m->wire(p);
+				log_assert(w);
+				if (w->port_input) {
+					if (w->attributes.count(ID(abc_scc_break)))
+						scc_break_inputs[m->name].insert(p);
+					if (w->attributes.count(ID(abc_carry))) {
+						if (carry_in)
+							log_error("Module '%s' contains more than one 'abc_carry' input port.\n", log_id(m));
+						carry_in = w;
+					}
+				}
+				if (w->port_output) {
+					if (w->attributes.count(ID(abc_carry))) {
+						if (carry_out)
+							log_error("Module '%s' contains more than one 'abc_carry' input port.\n", log_id(m));
+						carry_out = w;
+					}
+				}
+			}
+			if (carry_in || carry_out) {
+				if (carry_in && !carry_out)
+					log_error("Module '%s' contains an 'abc_carry' input port but no output port.\n", log_id(m));
+				if (!carry_in && carry_out)
+					log_error("Module '%s' contains an 'abc_carry' output port but no input port.\n", log_id(m));
+				// Make carry_in the last PI, and carry_out the last PO
+				//   since ABC requires it this way
+				auto &ports = m->ports;
+				for (auto it = ports.begin(); it != ports.end(); ) {
+					RTLIL::Wire* w = m->wire(*it);
+					log_assert(w);
+					if (w == carry_in || w == carry_out) {
+						it = ports.erase(it);
+						continue;
+					}
+					if (w->port_id > carry_in->port_id)
+						--w->port_id;
+					if (w->port_id > carry_out->port_id)
+						--w->port_id;
+					log_assert(w->port_input || w->port_output);
+					log_assert(ports[w->port_id-1] == w->name);
+					++it;
+				}
+				ports.push_back(carry_in->name);
+				carry_in->port_id = ports.size();
+				ports.push_back(carry_out->name);
+				carry_out->port_id = ports.size();
+			}
 		}
 
 		for (auto mod : design->selected_modules())
@@ -1110,7 +1147,7 @@ struct Abc9Pass : public Pass {
 			if (!dff_mode || !clk_str.empty()) {
 				abc9_module(design, mod, script_file, exe_file, cleanup, lut_costs, dff_mode, clk_str, keepff,
 						delay_target, lutin_shared, fast_mode, show_tempdir,
-						box_file, lut_file, wire_delay, box_lookup);
+						box_file, lut_file, wire_delay, box_lookup, scc_break_inputs);
 				continue;
 			}
 
@@ -1256,7 +1293,7 @@ struct Abc9Pass : public Pass {
 				en_sig = assign_map(std::get<3>(it.first));
 				abc9_module(design, mod, script_file, exe_file, cleanup, lut_costs, !clk_sig.empty(), "$",
 						keepff, delay_target, lutin_shared, fast_mode, show_tempdir,
-						box_file, lut_file, wire_delay, box_lookup);
+						box_file, lut_file, wire_delay, box_lookup, scc_break_inputs);
 				assign_map.set(mod);
 			}
 		}
diff --git a/passes/techmap/clkbufmap.cc b/passes/techmap/clkbufmap.cc
new file mode 100644
index 000000000..246932d81
--- /dev/null
+++ b/passes/techmap/clkbufmap.cc
@@ -0,0 +1,298 @@
+/*
+ *  yosys -- Yosys Open SYnthesis Suite
+ *
+ *  Copyright (C) 2012  Clifford Wolf <clifford@clifford.at>
+ *  Copyright (C) 2019  Marcin Kościelnicki <mwk@0x04.net>
+ *
+ *  Permission to use, copy, modify, and/or distribute this software for any
+ *  purpose with or without fee is hereby granted, provided that the above
+ *  copyright notice and this permission notice appear in all copies.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#include "kernel/yosys.h"
+#include "kernel/sigtools.h"
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+void split_portname_pair(std::string &port1, std::string &port2)
+{
+	size_t pos = port1.find_first_of(':');
+	if (pos != std::string::npos) {
+		port2 = port1.substr(pos+1);
+		port1 = port1.substr(0, pos);
+	}
+}
+
+struct ClkbufmapPass : public Pass {
+	ClkbufmapPass() : Pass("clkbufmap", "insert global buffers on clock networks") { }
+	void help() YS_OVERRIDE
+	{
+		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+		log("\n");
+		log("    clkbufmap [options] [selection]\n");
+		log("\n");
+		log("Inserts global buffers between nets connected to clock inputs and their drivers.\n");
+		log("\n");
+		log("In the absence of any selection, all wires without the 'clkbuf_inhibit'\n");
+		log("attribute will be considered for global buffer insertion.\n");
+		log("Alternatively, to consider all wires without the 'buffer_type' attribute set to\n");
+		log("'none' or 'bufr' one would specify:\n");
+		log("  'w:* a:buffer_type=none a:buffer_type=bufr %%u %%d'\n");
+		log("as the selection.\n");
+		log("\n");
+		log("    -buf <celltype> <portname_out>:<portname_in>\n");
+		log("        Specifies the cell type to use for the global buffers\n");
+		log("        and its port names.  The first port will be connected to\n");
+		log("        the clock network sinks, and the second will be connected\n");
+		log("        to the actual clock source.  This option is required.\n");
+		log("\n");
+		log("    -inpad <celltype> <portname_out>:<portname_in>\n");
+		log("        If specified, a PAD cell of the given type is inserted on\n");
+		log("        clock nets that are also top module's inputs (in addition\n");
+		log("        to the global buffer).\n");
+		log("\n");
+	}
+
+	void module_queue(Design *design, Module *module, std::vector<Module *> &modules_sorted, pool<Module *> &modules_processed) {
+		if (modules_processed.count(module))
+			return;
+		for (auto cell : module->cells()) {
+			Module *submodule = design->module(cell->type);
+			if (!submodule)
+				continue;
+			module_queue(design, submodule, modules_sorted, modules_processed);
+		}
+		modules_sorted.push_back(module);
+		modules_processed.insert(module);
+	}
+
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
+	{
+		log_header(design, "Executing CLKBUFMAP pass (inserting global clock buffers).\n");
+
+		std::string buf_celltype, buf_portname, buf_portname2;
+		std::string inpad_celltype, inpad_portname, inpad_portname2;
+
+		size_t argidx;
+		for (argidx = 1; argidx < args.size(); argidx++)
+		{
+			std::string arg = args[argidx];
+			if (arg == "-buf" && argidx+2 < args.size()) {
+				buf_celltype = args[++argidx];
+				buf_portname = args[++argidx];
+				split_portname_pair(buf_portname, buf_portname2);
+				continue;
+			}
+			if (arg == "-inpad" && argidx+2 < args.size()) {
+				inpad_celltype = args[++argidx];
+				inpad_portname = args[++argidx];
+				split_portname_pair(inpad_portname, inpad_portname2);
+				continue;
+			}
+			break;
+		}
+
+		bool select = false;
+		if (argidx < args.size()) {
+			if (args[argidx].compare(0, 1, "-") != 0)
+				select = true;
+			extra_args(args, argidx, design);
+		}
+
+		if (buf_celltype.empty())
+			log_error("The -buf option is required.\n");
+
+		// Cell type, port name, bit index.
+		pool<pair<IdString, pair<IdString, int>>> sink_ports;
+		pool<pair<IdString, pair<IdString, int>>> buf_ports;
+
+		// Process submodules before module using them.
+		std::vector<Module *> modules_sorted;
+		pool<Module *> modules_processed;
+		for (auto module : design->selected_modules())
+			module_queue(design, module, modules_sorted, modules_processed);
+
+		for (auto module : modules_sorted)
+		{
+			if (module->get_blackbox_attribute()) {
+				for (auto port : module->ports) {
+					auto wire = module->wire(port);
+					if (wire->get_bool_attribute("\\clkbuf_driver"))
+						for (int i = 0; i < GetSize(wire); i++)
+							buf_ports.insert(make_pair(module->name, make_pair(wire->name, i)));
+					if (wire->get_bool_attribute("\\clkbuf_sink"))
+						for (int i = 0; i < GetSize(wire); i++)
+							sink_ports.insert(make_pair(module->name, make_pair(wire->name, i)));
+				}
+				continue;
+			}
+			pool<SigBit> sink_wire_bits;
+			pool<SigBit> buf_wire_bits;
+			pool<SigBit> driven_wire_bits;
+			SigMap sigmap(module);
+			// bit -> (buffer, buffer's input)
+			dict<SigBit, pair<Cell *, Wire *>> buffered_bits;
+
+			// First, collect nets that could use a clock buffer.
+			for (auto cell : module->cells())
+			for (auto port : cell->connections())
+			for (int i = 0; i < port.second.size(); i++)
+				if (sink_ports.count(make_pair(cell->type, make_pair(port.first, i))))
+					sink_wire_bits.insert(sigmap(port.second[i]));
+
+			// Second, collect ones that already have a clock buffer.
+			for (auto cell : module->cells())
+			for (auto port : cell->connections())
+			for (int i = 0; i < port.second.size(); i++)
+				if (buf_ports.count(make_pair(cell->type, make_pair(port.first, i))))
+					buf_wire_bits.insert(sigmap(port.second[i]));
+
+			// Collect all driven bits.
+			for (auto cell : module->cells())
+			for (auto port : cell->connections())
+				if (cell->output(port.first))
+					for (int i = 0; i < port.second.size(); i++)
+						driven_wire_bits.insert(port.second[i]);
+
+			// Insert buffers.
+			std::vector<pair<Wire *, Wire *>> input_queue;
+			// Copy current wire list, as we will be adding new ones during iteration.
+			std::vector<Wire *> wires(module->wires());
+			for (auto wire : wires)
+			{
+				// Should not happen.
+				if (wire->port_input && wire->port_output)
+					continue;
+				bool process_wire = module->selected(wire);
+				if (!select && wire->get_bool_attribute("\\clkbuf_inhibit"))
+					process_wire = false;
+				if (!process_wire) {
+					// This wire is supposed to be bypassed, so make sure we don't buffer it in
+					// some buffer higher up in the hierarchy.
+					if (wire->port_output)
+						for (int i = 0; i < GetSize(wire); i++)
+							buf_ports.insert(make_pair(module->name, make_pair(wire->name, i)));
+					continue;
+				}
+
+				pool<int> input_bits;
+
+				for (int i = 0; i < GetSize(wire); i++)
+				{
+					SigBit wire_bit(wire, i);
+					SigBit mapped_wire_bit = sigmap(wire_bit);
+					if (buf_wire_bits.count(mapped_wire_bit)) {
+						// Already buffered downstream.  If this is an output, mark it.
+						if (wire->port_output)
+							buf_ports.insert(make_pair(module->name, make_pair(wire->name, i)));
+					} else if (!sink_wire_bits.count(mapped_wire_bit)) {
+						// Nothing to do.
+					} else if (driven_wire_bits.count(wire_bit) || (wire->port_input && module->get_bool_attribute("\\top"))) {
+						// Clock network not yet buffered, driven by one of
+						// our cells or a top-level input -- buffer it.
+
+						log("Inserting %s on %s.%s[%d].\n", buf_celltype.c_str(), log_id(module), log_id(wire), i);
+						RTLIL::Cell *cell = module->addCell(NEW_ID, RTLIL::escape_id(buf_celltype));
+						Wire *iwire = module->addWire(NEW_ID);
+						cell->setPort(RTLIL::escape_id(buf_portname), mapped_wire_bit);
+						cell->setPort(RTLIL::escape_id(buf_portname2), iwire);
+						if (wire->port_input && !inpad_celltype.empty() && module->get_bool_attribute("\\top")) {
+							log("Inserting %s on %s.%s[%d].\n", inpad_celltype.c_str(), log_id(module), log_id(wire), i);
+							RTLIL::Cell *cell2 = module->addCell(NEW_ID, RTLIL::escape_id(inpad_celltype));
+							cell2->setPort(RTLIL::escape_id(inpad_portname), iwire);
+							iwire = module->addWire(NEW_ID);
+							cell2->setPort(RTLIL::escape_id(inpad_portname2), iwire);
+						}
+						buffered_bits[mapped_wire_bit] = make_pair(cell, iwire);
+
+						if (wire->port_input) {
+							input_bits.insert(i);
+						}
+					} else if (wire->port_input) {
+						// A clock input in a submodule -- mark it, let higher level
+						// worry about it.
+						if (wire->port_input)
+							sink_ports.insert(make_pair(module->name, make_pair(wire->name, i)));
+					}
+				}
+				if (!input_bits.empty()) {
+					// This is an input port and some buffers were inserted -- we need
+					// to create a new input wire and transfer attributes.
+					Wire *new_wire = module->addWire(NEW_ID, wire);
+
+					for (int i = 0; i < wire->width; i++) {
+						SigBit wire_bit(wire, i);
+						SigBit mapped_wire_bit = sigmap(wire_bit);
+						auto it = buffered_bits.find(mapped_wire_bit);
+						if (it != buffered_bits.end()) {
+
+							module->connect(it->second.second, SigSpec(new_wire, i));
+						} else {
+							module->connect(SigSpec(wire, i), SigSpec(new_wire, i));
+						}
+					}
+					input_queue.push_back(make_pair(wire, new_wire));
+				}
+			}
+
+			// Mark any newly-buffered output ports as such.
+			for (auto wire : module->selected_wires()) {
+				if (wire->port_input || !wire->port_output)
+					continue;
+				for (int i = 0; i < GetSize(wire); i++)
+				{
+					SigBit wire_bit(wire, i);
+					SigBit mapped_wire_bit = sigmap(wire_bit);
+					if (buffered_bits.count(mapped_wire_bit))
+						buf_ports.insert(make_pair(module->name, make_pair(wire->name, i)));
+				}
+			}
+
+			// Reconnect the drivers to buffer inputs.
+			for (auto cell : module->cells())
+			for (auto port : cell->connections()) {
+				if (!cell->output(port.first))
+					continue;
+				SigSpec sig = port.second;
+				bool newsig = false;
+				for (auto &bit : sig) {
+					const auto it = buffered_bits.find(sigmap(bit));
+					if (it == buffered_bits.end())
+						continue;
+					// Avoid substituting buffer's own output pin.
+					if (cell == it->second.first)
+						continue;
+					bit = it->second.second;
+					newsig = true;
+				}
+				if (newsig)
+					cell->setPort(port.first, sig);
+			}
+
+			// This has to be done last, to avoid upsetting sigmap before the port reconnections.
+			for (auto &it : input_queue) {
+				Wire *wire = it.first;
+				Wire *new_wire = it.second;
+				module->swap_names(new_wire, wire);
+				wire->attributes.clear();
+				wire->port_id = 0;
+				wire->port_input = false;
+				wire->port_output = false;
+			}
+
+			module->fixup_ports();
+		}
+	}
+} ClkbufmapPass;
+
+PRIVATE_NAMESPACE_END
diff --git a/passes/techmap/iopadmap.cc b/passes/techmap/iopadmap.cc
index a2551316f..c868b9a87 100644
--- a/passes/techmap/iopadmap.cc
+++ b/passes/techmap/iopadmap.cc
@@ -64,6 +64,11 @@ struct IopadmapPass : public Pass {
 		log("        of the tristate driver and the 2nd portname is the internal output\n");
 		log("        buffering the external signal.\n");
 		log("\n");
+		log("    -ignore <celltype> <portname>[:<portname>]*\n");
+		log("        Skips mapping inputs/outputs that are already connected to given\n");
+		log("        ports of the given cell.  Can be used multiple times.  This is in\n");
+		log("        addition to the cells specified as mapping targets.\n");
+		log("\n");
 		log("    -widthparam <param_name>\n");
 		log("        Use the specified parameter name to set the port width.\n");
 		log("\n");
@@ -88,6 +93,7 @@ struct IopadmapPass : public Pass {
 		std::string toutpad_celltype, toutpad_portname, toutpad_portname2, toutpad_portname3;
 		std::string tinoutpad_celltype, tinoutpad_portname, tinoutpad_portname2, tinoutpad_portname3, tinoutpad_portname4;
 		std::string widthparam, nameparam;
+		pool<pair<IdString, IdString>> ignore;
 		bool flag_bits = false;
 
 		size_t argidx;
@@ -127,6 +133,18 @@ struct IopadmapPass : public Pass {
 				split_portname_pair(tinoutpad_portname3, tinoutpad_portname4);
 				continue;
 			}
+			if (arg == "-ignore" && argidx+2 < args.size()) {
+				std::string ignore_celltype = args[++argidx];
+				std::string ignore_portname = args[++argidx];
+				std::string ignore_portname2;
+				while (!ignore_portname.empty()) {
+					split_portname_pair(ignore_portname, ignore_portname2);
+					ignore.insert(make_pair(RTLIL::escape_id(ignore_celltype), RTLIL::escape_id(ignore_portname)));
+
+					ignore_portname = ignore_portname2;
+				}
+				continue;
+			}
 			if (arg == "-widthparam" && argidx+1 < args.size()) {
 				widthparam = args[++argidx];
 				continue;
@@ -143,6 +161,23 @@ struct IopadmapPass : public Pass {
 		}
 		extra_args(args, argidx, design);
 
+		if (!inpad_portname2.empty())
+			ignore.insert(make_pair(RTLIL::escape_id(inpad_celltype), RTLIL::escape_id(inpad_portname2)));
+		if (!outpad_portname2.empty())
+			ignore.insert(make_pair(RTLIL::escape_id(outpad_celltype), RTLIL::escape_id(outpad_portname2)));
+		if (!inoutpad_portname2.empty())
+			ignore.insert(make_pair(RTLIL::escape_id(inoutpad_celltype), RTLIL::escape_id(inoutpad_portname2)));
+		if (!toutpad_portname3.empty())
+			ignore.insert(make_pair(RTLIL::escape_id(toutpad_celltype), RTLIL::escape_id(toutpad_portname3)));
+		if (!tinoutpad_portname4.empty())
+			ignore.insert(make_pair(RTLIL::escape_id(tinoutpad_celltype), RTLIL::escape_id(tinoutpad_portname4)));
+
+		for (auto module : design->modules())
+			if (module->get_blackbox_attribute())
+				for (auto wire : module->wires())
+					if (wire->get_bool_attribute("\\iopad_external_pin"))
+						ignore.insert(make_pair(module->name, wire->name));
+
 		for (auto module : design->selected_modules())
 		{
 			dict<IdString, pool<int>> skip_wires;
@@ -150,28 +185,11 @@ struct IopadmapPass : public Pass {
 			SigMap sigmap(module);
 
 			for (auto cell : module->cells())
-			{
-				if (cell->type == RTLIL::escape_id(inpad_celltype) && cell->hasPort(RTLIL::escape_id(inpad_portname2)))
-					for (auto bit : sigmap(cell->getPort(RTLIL::escape_id(inpad_portname2))))
-						skip_wire_bits.insert(bit);
-
-				if (cell->type == RTLIL::escape_id(outpad_celltype) && cell->hasPort(RTLIL::escape_id(outpad_portname2)))
-					for (auto bit : sigmap(cell->getPort(RTLIL::escape_id(outpad_portname2))))
+			for (auto port : cell->connections())
+				if (ignore.count(make_pair(cell->type, port.first)))
+					for (auto bit : sigmap(port.second))
 						skip_wire_bits.insert(bit);
 
-				if (cell->type == RTLIL::escape_id(inoutpad_celltype) && cell->hasPort(RTLIL::escape_id(inoutpad_portname2)))
-					for (auto bit : sigmap(cell->getPort(RTLIL::escape_id(inoutpad_portname2))))
-						skip_wire_bits.insert(bit);
-
-				if (cell->type == RTLIL::escape_id(toutpad_celltype) && cell->hasPort(RTLIL::escape_id(toutpad_portname3)))
-					for (auto bit : sigmap(cell->getPort(RTLIL::escape_id(toutpad_portname3))))
-						skip_wire_bits.insert(bit);
-
-				if (cell->type == RTLIL::escape_id(tinoutpad_celltype) && cell->hasPort(RTLIL::escape_id(tinoutpad_portname4)))
-					for (auto bit : sigmap(cell->getPort(RTLIL::escape_id(tinoutpad_portname4))))
-						skip_wire_bits.insert(bit);
-			}
-
 			if (!toutpad_celltype.empty() || !tinoutpad_celltype.empty())
 			{
 				dict<SigBit, pair<IdString, pool<IdString>>> tbuf_bits;
diff --git a/passes/techmap/techmap.cc b/passes/techmap/techmap.cc
index b271c8781..c4496f76f 100644
--- a/passes/techmap/techmap.cc
+++ b/passes/techmap/techmap.cc
@@ -943,7 +943,8 @@ struct TechmapPass : public Pass {
 		log("        instead of inlining them.\n");
 		log("\n");
 		log("    -max_iter <number>\n");
-		log("        only run the specified number of iterations.\n");
+		log("        only run the specified number of iterations on each module.\n");
+		log("        default: unlimited\n");
 		log("\n");
 		log("    -recursive\n");
 		log("        instead of the iterative breadth-first algorithm use a recursive\n");
@@ -1157,15 +1158,16 @@ struct TechmapPass : public Pass {
 			RTLIL::Module *module = *worker.module_queue.begin();
 			worker.module_queue.erase(module);
 
+			int module_max_iter = max_iter;
 			bool did_something = true;
 			std::set<RTLIL::Cell*> handled_cells;
 			while (did_something) {
 				did_something = false;
-					if (worker.techmap_module(design, module, map, handled_cells, celltypeMap, false))
-						did_something = true;
+				if (worker.techmap_module(design, module, map, handled_cells, celltypeMap, false))
+					did_something = true;
 				if (did_something)
 					module->check();
-				if (max_iter > 0 && --max_iter == 0)
+				if (module_max_iter > 0 && --module_max_iter == 0)
 					break;
 			}
 		}
diff --git a/techlibs/anlogic/Makefile.inc b/techlibs/anlogic/Makefile.inc
index 67cf9cf10..9426b5ca5 100644
--- a/techlibs/anlogic/Makefile.inc
+++ b/techlibs/anlogic/Makefile.inc
@@ -1,7 +1,7 @@
 
 OBJS += techlibs/anlogic/synth_anlogic.o
 OBJS += techlibs/anlogic/anlogic_eqn.o
-OBJS += techlibs/anlogic/anlogic_determine_init.o
+OBJS += techlibs/anlogic/anlogic_fixcarry.o
 
 $(eval $(call add_share_file,share/anlogic,techlibs/anlogic/cells_map.v))
 $(eval $(call add_share_file,share/anlogic,techlibs/anlogic/arith_map.v))
diff --git a/techlibs/anlogic/anlogic_determine_init.cc b/techlibs/anlogic/anlogic_determine_init.cc
deleted file mode 100644
index c4089dac2..000000000
--- a/techlibs/anlogic/anlogic_determine_init.cc
+++ /dev/null
@@ -1,72 +0,0 @@
-/*
- *  yosys -- Yosys Open SYnthesis Suite
- *
- *  Copyright (C) 2018 Icenowy Zheng <icenowy@aosc.io>
- *
- *  Permission to use, copy, modify, and/or distribute this software for any
- *  purpose with or without fee is hereby granted, provided that the above
- *  copyright notice and this permission notice appear in all copies.
- *
- *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
- *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
- *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
- *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
- *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
- *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
- *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
- *
- */
-
-#include "kernel/yosys.h"
-#include "kernel/sigtools.h"
-
-USING_YOSYS_NAMESPACE
-PRIVATE_NAMESPACE_BEGIN
-
-struct AnlogicDetermineInitPass : public Pass {
-	AnlogicDetermineInitPass() : Pass("anlogic_determine_init", "Anlogic: Determine the init value of cells") { }
-	void help() YS_OVERRIDE
-	{
-		log("\n");
-		log("    anlogic_determine_init [selection]\n");
-		log("\n");
-		log("Determine the init value of cells that doesn't allow unknown init value.\n");
-		log("\n");
-	}
-
-	Const determine_init(Const init)
-	{
-		for (int i = 0; i < GetSize(init); i++) {
-			if (init[i] != State::S0 && init[i] != State::S1)
-				init[i] = State::S0;
-		}
-
-		return init;
-	}
-
-	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
-	{
-		log_header(design, "Executing ANLOGIC_DETERMINE_INIT pass (determine init value for cells).\n");
-
-		extra_args(args, args.size(), design);
-
-		int cnt = 0;
-		for (auto module : design->selected_modules())
-		{
-			for (auto cell : module->selected_cells())
-			{
-				if (cell->type == "\\EG_LOGIC_DRAM16X4")
-				{
-					cell->setParam("\\INIT_D0", determine_init(cell->getParam("\\INIT_D0")));
-					cell->setParam("\\INIT_D1", determine_init(cell->getParam("\\INIT_D1")));
-					cell->setParam("\\INIT_D2", determine_init(cell->getParam("\\INIT_D2")));
-					cell->setParam("\\INIT_D3", determine_init(cell->getParam("\\INIT_D3")));
-					cnt++;
-				}
-			}
-		}
-		log_header(design, "Updated %d cells with determined init value.\n", cnt);
-	}
-} AnlogicDetermineInitPass;
-
-PRIVATE_NAMESPACE_END
diff --git a/techlibs/anlogic/anlogic_fixcarry.cc b/techlibs/anlogic/anlogic_fixcarry.cc
new file mode 100644
index 000000000..87164d375
--- /dev/null
+++ b/techlibs/anlogic/anlogic_fixcarry.cc
@@ -0,0 +1,130 @@
+/*
+ *  yosys -- Yosys Open SYnthesis Suite
+ *
+ *  Copyright (C) 2019  Miodrag Milanovic <miodrag@symbioticeda.com>
+ *
+ *  Permission to use, copy, modify, and/or distribute this software for any
+ *  purpose with or without fee is hereby granted, provided that the above
+ *  copyright notice and this permission notice appear in all copies.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#include "kernel/yosys.h"
+#include "kernel/sigtools.h"
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+static SigBit get_bit_or_zero(const SigSpec &sig)
+{
+	if (GetSize(sig) == 0)
+		return State::S0;
+	return sig[0];
+}
+
+static void fix_carry_chain(Module *module)
+{
+	SigMap sigmap(module);
+
+	pool<SigBit> ci_bits;
+	dict<SigBit, SigBit> mapping_bits;
+
+	for (auto cell : module->cells())
+	{
+		if (cell->type == "\\AL_MAP_ADDER") {
+			if (cell->getParam("\\ALUTYPE") != Const("ADD")) continue;
+			SigBit bit_i0 = get_bit_or_zero(cell->getPort("\\a"));
+			SigBit bit_i1 = get_bit_or_zero(cell->getPort("\\b"));
+			if (bit_i0 == State::S0 && bit_i1== State::S0) {
+				SigBit bit_ci = get_bit_or_zero(cell->getPort("\\c"));
+				SigSpec o = cell->getPort("\\o");
+				if (GetSize(o) == 2) {
+					SigBit bit_o = o[0];
+					ci_bits.insert(bit_ci);				
+					mapping_bits[bit_ci] = bit_o;				
+				}
+			}
+		}
+	}
+	vector<Cell*> adders_to_fix_cells;
+	for (auto cell : module->cells())
+	{
+		if (cell->type == "\\AL_MAP_ADDER") {
+			if (cell->getParam("\\ALUTYPE") != Const("ADD")) continue;
+			SigBit bit_ci = get_bit_or_zero(cell->getPort("\\c"));
+			SigBit bit_i0 = get_bit_or_zero(cell->getPort("\\a"));
+			SigBit bit_i1 = get_bit_or_zero(cell->getPort("\\b"));			
+			SigBit canonical_bit = sigmap(bit_ci);
+			if (!ci_bits.count(canonical_bit))
+				continue;			
+			if (bit_i0 == State::S0 && bit_i1== State::S0) 
+				continue;
+
+			adders_to_fix_cells.push_back(cell);
+			log("Found %s cell named %s with invalid 'c' signal.\n", log_id(cell->type), log_id(cell));
+		}
+	}
+
+	for (auto cell : adders_to_fix_cells)
+	{
+		SigBit bit_ci = get_bit_or_zero(cell->getPort("\\c"));
+		SigBit canonical_bit = sigmap(bit_ci);
+		auto bit = mapping_bits.at(canonical_bit);
+		log("Fixing %s cell named %s breaking carry chain.\n", log_id(cell->type), log_id(cell));
+		Cell *c = module->addCell(NEW_ID, "\\AL_MAP_ADDER");
+		SigBit new_bit = module->addWire(NEW_ID);
+		SigBit dummy_bit = module->addWire(NEW_ID);
+		SigSpec bits;
+		bits.append(dummy_bit);
+		bits.append(new_bit);
+		c->setParam("\\ALUTYPE", Const("ADD_CARRY"));
+		c->setPort("\\a", bit);
+		c->setPort("\\b", State::S0);
+		c->setPort("\\c", State::S0);
+		c->setPort("\\o", bits);
+		
+		cell->setPort("\\c", new_bit);
+	}
+	
+}
+
+struct AnlogicCarryFixPass : public Pass {
+	AnlogicCarryFixPass() : Pass("anlogic_fixcarry", "Anlogic: fix carry chain") { }
+	void help() YS_OVERRIDE
+	{
+		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+		log("\n");
+		log("    anlogic_fixcarry [options] [selection]\n");
+		log("\n");
+		log("Add Anlogic adders to fix carry chain if needed.\n");
+		log("\n");
+	}
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
+	{
+		log_header(design, "Executing anlogic_fixcarry pass (fix invalid carry chain).\n");
+		
+		size_t argidx;
+		for (argidx = 1; argidx < args.size(); argidx++)
+		{
+			break;
+		}
+		extra_args(args, argidx, design);
+
+		Module *module = design->top_module();
+
+		if (module == nullptr)
+			log_cmd_error("No top module found.\n");
+
+		fix_carry_chain(module);		
+	}
+} AnlogicCarryFixPass;
+
+PRIVATE_NAMESPACE_END
diff --git a/techlibs/anlogic/arith_map.v b/techlibs/anlogic/arith_map.v
index 6d6a7ca37..1186543da 100644
--- a/techlibs/anlogic/arith_map.v
+++ b/techlibs/anlogic/arith_map.v
@@ -31,7 +31,10 @@ module _80_anlogic_alu (A, B, CI, BI, X, Y, CO);
 	output [Y_WIDTH-1:0] X, Y;
 
 	input CI, BI;
-	output CO;
+	output [Y_WIDTH-1:0] CO;
+   
+	wire CIx;
+	wire [Y_WIDTH-1:0] COx;
 
 	wire _TECHMAP_FAIL_ = Y_WIDTH <= 2;
 
@@ -41,15 +44,16 @@ module _80_anlogic_alu (A, B, CI, BI, X, Y, CO);
 
 	wire [Y_WIDTH-1:0] AA = A_buf;
 	wire [Y_WIDTH-1:0] BB = BI ? ~B_buf : B_buf;
-	wire [Y_WIDTH+1:0] COx;
-	wire [Y_WIDTH+2:0] C = {COx, CI};
+	wire [Y_WIDTH-1:0] C = { COx, CIx };
 
     wire dummy;
     AL_MAP_ADDER #(
     	.ALUTYPE("ADD_CARRY"))
     adder_cin  (
-        .a(C[0]),
-        .o({COx[0], dummy})
+        .a(CI),
+		.b(1'b0),
+		.c(1'b0),
+        .o({CIx, dummy})
 	);
 
 	genvar i;
@@ -59,18 +63,22 @@ module _80_anlogic_alu (A, B, CI, BI, X, Y, CO);
         ) adder_i (
             .a(AA[i]),
             .b(BB[i]),
-            .c(C[i+1]),
-            .o({COx[i+1],Y[i]})
+            .c(C[i]),
+            .o({COx[i],Y[i]})
         );
-	  end: slice
+
+		wire cout;
+		AL_MAP_ADDER #(
+			.ALUTYPE("ADD"))
+		adder_cout  (
+			.a(1'b0),
+			.b(1'b0),
+			.c(COx[i]),
+			.o({cout, CO[i]})
+		);
+	  end: slice	  
 	endgenerate
-	/* End implementation */
-	AL_MAP_ADDER #(
-		.ALUTYPE("ADD"))
-	adder_cout  (
-		.c(C[Y_WIDTH+1]),
-		.o(COx[Y_WIDTH+1])
-	);				
-	assign CO = COx[Y_WIDTH+1];
-	assign X = AA ^ BB;
-endmodule
\ No newline at end of file
+
+   /* End implementation */
+   assign X = AA ^ BB;
+endmodule
diff --git a/techlibs/anlogic/synth_anlogic.cc b/techlibs/anlogic/synth_anlogic.cc
index 620bf3965..b87fc8566 100644
--- a/techlibs/anlogic/synth_anlogic.cc
+++ b/techlibs/anlogic/synth_anlogic.cc
@@ -154,7 +154,7 @@ struct SynthAnlogicPass : public ScriptPass
 		{
 			run("memory_bram -rules +/anlogic/drams.txt");
 			run("techmap -map +/anlogic/drams_map.v");
-			run("anlogic_determine_init");
+			run("setundef -zero -params t:EG_LOGIC_DRAM16X4");
 		}
 
 		if (check_label("fine"))
@@ -186,6 +186,11 @@ struct SynthAnlogicPass : public ScriptPass
 		{
 			run("techmap -map +/anlogic/cells_map.v");
 			run("clean");
+		}
+		
+		if (check_label("map_anlogic"))
+		{
+			run("anlogic_fixcarry");
 			run("anlogic_eqn");
 		}
 
diff --git a/techlibs/common/synth.cc b/techlibs/common/synth.cc
index 555de9fba..a176357a7 100644
--- a/techlibs/common/synth.cc
+++ b/techlibs/common/synth.cc
@@ -175,7 +175,7 @@ struct SynthPass : public ScriptPass
 			log_cmd_error("This command only operates on fully selected designs!\n");
 
 		if (abc == "abc9" && !lut)
-			log_cmd_error("ABC9 flow only supported for FPGA synthesis (using '-lut' option)");
+			log_cmd_error("ABC9 flow only supported for FPGA synthesis (using '-lut' option)\n");
 
 		log_header(design, "Executing SYNTH pass.\n");
 		log_push();
diff --git a/techlibs/ecp5/cells_sim.v b/techlibs/ecp5/cells_sim.v
index 3d343b315..dc8334acb 100644
--- a/techlibs/ecp5/cells_sim.v
+++ b/techlibs/ecp5/cells_sim.v
@@ -15,10 +15,15 @@ module L6MUX21 (input D0, D1, SD, output Z);
 endmodule
 
 // ---------------------------------------
-(* abc_box_id=1, abc_carry="CIN,COUT", lib_whitebox *)
-module CCU2C(input CIN, A0, B0, C0, D0, A1, B1, C1, D1,
-	           output S0, S1, COUT);
-
+(* abc_box_id=1, lib_whitebox *)
+module CCU2C(
+	(* abc_carry *)
+	input  CIN,
+	input  A0, B0, C0, D0, A1, B1, C1, D1,
+	output S0, S1,
+	(* abc_carry *)
+	output COUT
+);
 	parameter [15:0] INIT0 = 16'h0000;
 	parameter [15:0] INIT1 = 16'h0000;
 	parameter INJECT1_0 = "YES";
@@ -104,12 +109,16 @@ module PFUMX (input ALUT, BLUT, C0, output Z);
 endmodule
 
 // ---------------------------------------
-//(* abc_box_id=2, abc_scc_break="DI,WAD,WRE" *)
+//(* abc_box_id=2 *)
 module TRELLIS_DPR16X4 (
-	input [3:0] DI,
-	input [3:0] WAD,
-	input WRE, WCK,
-	input [3:0] RAD,
+	(* abc_scc_break *)
+	input  [3:0] DI,
+	(* abc_scc_break *)
+	input  [3:0] WAD,
+	(* abc_scc_break *)
+	input        WRE,
+	input        WCK,
+	input  [3:0] RAD,
 	output [3:0] DO
 );
 	parameter WCKMUX = "WCK";
diff --git a/techlibs/efinix/Makefile.inc b/techlibs/efinix/Makefile.inc
new file mode 100644
index 000000000..5013f7fc1
--- /dev/null
+++ b/techlibs/efinix/Makefile.inc
@@ -0,0 +1,10 @@
+
+OBJS += techlibs/efinix/synth_efinix.o
+OBJS += techlibs/efinix/efinix_gbuf.o
+OBJS += techlibs/efinix/efinix_fixcarry.o
+
+$(eval $(call add_share_file,share/efinix,techlibs/efinix/cells_map.v))
+$(eval $(call add_share_file,share/efinix,techlibs/efinix/arith_map.v))
+$(eval $(call add_share_file,share/efinix,techlibs/efinix/cells_sim.v))
+$(eval $(call add_share_file,share/efinix,techlibs/efinix/brams_map.v))
+$(eval $(call add_share_file,share/efinix,techlibs/efinix/bram.txt))
diff --git a/techlibs/efinix/arith_map.v b/techlibs/efinix/arith_map.v
new file mode 100644
index 000000000..178f57bc5
--- /dev/null
+++ b/techlibs/efinix/arith_map.v
@@ -0,0 +1,79 @@
+/*
+ *  yosys -- Yosys Open SYnthesis Suite
+ *
+ *  Copyright (C) 2018  Miodrag Milanovic <miodrag@symbioticeda.com>
+ *  Copyright (C) 2012  Clifford Wolf <clifford@clifford.at>
+ *
+ *  Permission to use, copy, modify, and/or distribute this software for any
+ *  purpose with or without fee is hereby granted, provided that the above
+ *  copyright notice and this permission notice appear in all copies.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+(* techmap_celltype = "$alu" *)
+module _80_efinix_alu (A, B, CI, BI, X, Y, CO);
+	parameter A_SIGNED = 0;
+	parameter B_SIGNED = 0;
+	parameter A_WIDTH  = 1;
+	parameter B_WIDTH  = 1;
+	parameter Y_WIDTH  = 1;
+
+	input [A_WIDTH-1:0] A;
+	input [B_WIDTH-1:0] B;
+	output [Y_WIDTH-1:0] X, Y;
+
+	input CI, BI;
+	output [Y_WIDTH-1:0] CO;
+   
+    wire CIx;
+    wire [Y_WIDTH-1:0] COx;
+
+	wire _TECHMAP_FAIL_ = Y_WIDTH <= 2;
+
+	wire [Y_WIDTH-1:0] A_buf, B_buf;
+	\$pos #(.A_SIGNED(A_SIGNED), .A_WIDTH(A_WIDTH), .Y_WIDTH(Y_WIDTH)) A_conv (.A(A), .Y(A_buf));
+	\$pos #(.A_SIGNED(B_SIGNED), .A_WIDTH(B_WIDTH), .Y_WIDTH(Y_WIDTH)) B_conv (.A(B), .Y(B_buf));
+
+	wire [Y_WIDTH-1:0] AA = A_buf;
+	wire [Y_WIDTH-1:0] BB = BI ? ~B_buf : B_buf;
+	wire [Y_WIDTH-1:0] C = { COx, CIx };
+
+    EFX_ADD #(.I0_POLARITY(1'b1),.I1_POLARITY(1'b1))
+    adder_cin  (
+        .I0(CI),
+        .I1(1'b1),
+        .CI(1'b0),
+        .CO(CIx)
+	);
+
+	genvar i;
+	generate for (i = 0; i < Y_WIDTH; i = i + 1) begin: slice
+		EFX_ADD #(.I0_POLARITY(1'b1),.I1_POLARITY(1'b1))
+		adder_i (
+			.I0(AA[i]),
+			.I1(BB[i]),
+			.CI(C[i]),
+			.O(Y[i]),
+			.CO(COx[i])
+		);
+		EFX_ADD #(.I0_POLARITY(1'b1),.I1_POLARITY(1'b1))				
+		adder_cout  (
+			.I0(1'b0),
+			.I1(1'b0),
+			.CI(COx[i]),
+			.O(CO[i])
+		);
+	  end: slice	  
+	endgenerate
+
+   /* End implementation */
+   assign X = AA ^ BB;
+endmodule
\ No newline at end of file
diff --git a/techlibs/efinix/bram.txt b/techlibs/efinix/bram.txt
new file mode 100644
index 000000000..0b3fd9308
--- /dev/null
+++ b/techlibs/efinix/bram.txt
@@ -0,0 +1,32 @@
+bram $__EFINIX_5K
+  init 1
+
+  abits 8  @a8d16
+  dbits 16 @a8d16
+  abits 9  @a9d8
+  dbits 8  @a9d8
+  abits 10 @a10d4
+  dbits 4  @a10d4
+  abits 11 @a11d2
+  dbits 2  @a11d2
+  abits 12 @a12d1
+  dbits 1  @a12d1
+  abits 8  @a8d20
+  dbits 20 @a8d20
+  abits 9  @a9d10
+  dbits 10 @a9d10
+
+  groups 2
+  ports 1 1
+  wrmode 1 0
+  enable 1 1
+  transp 0 2
+  clocks 2 3
+  clkpol 2 3
+endbram
+
+match $__EFINIX_5K
+  min bits 256
+  min efficiency 5
+  shuffle_enable B
+endmatch
diff --git a/techlibs/efinix/brams_map.v b/techlibs/efinix/brams_map.v
new file mode 100644
index 000000000..6786ae769
--- /dev/null
+++ b/techlibs/efinix/brams_map.v
@@ -0,0 +1,65 @@
+module \$__EFINIX_5K (CLK2, CLK3, A1ADDR, A1DATA, A1EN, B1ADDR, B1DATA, B1EN);
+	parameter CFG_ABITS = 8;
+	parameter CFG_DBITS = 20;
+	parameter CFG_ENABLE_A = 1;
+
+	parameter CLKPOL2 = 1;
+	parameter CLKPOL3 = 1;
+	parameter [5119:0] INIT = 5119'bx;
+	parameter TRANSP2 = 0;
+
+	input CLK2;
+	input CLK3;
+
+	input [CFG_ABITS-1:0] A1ADDR;
+	input [CFG_DBITS-1:0] A1DATA;
+	input [CFG_ENABLE_A-1:0] A1EN;
+
+	input [CFG_ABITS-1:0] B1ADDR;
+	output [CFG_DBITS-1:0] B1DATA;
+	input B1EN;
+
+	localparam WRITEMODE_A = TRANSP2 ? "WRITE_FIRST" : "READ_FIRST";
+
+	EFX_RAM_5K #(
+   		.READ_WIDTH(CFG_DBITS),
+   		.WRITE_WIDTH(CFG_DBITS),
+   		.OUTPUT_REG(1'b0),
+   		.RCLK_POLARITY(1'b1),
+   		.RE_POLARITY(1'b1),
+   		.WCLK_POLARITY(1'b1),
+   		.WE_POLARITY(1'b1),
+   		.WCLKE_POLARITY(1'b1),
+   		.WRITE_MODE(WRITEMODE_A),
+		.INIT_0(INIT[ 0*256 +: 256]),
+		.INIT_1(INIT[ 1*256 +: 256]),
+		.INIT_2(INIT[ 2*256 +: 256]),
+		.INIT_3(INIT[ 3*256 +: 256]),
+		.INIT_4(INIT[ 4*256 +: 256]),
+		.INIT_5(INIT[ 5*256 +: 256]),
+		.INIT_6(INIT[ 6*256 +: 256]),
+		.INIT_7(INIT[ 7*256 +: 256]),
+		.INIT_8(INIT[ 8*256 +: 256]),
+		.INIT_9(INIT[ 9*256 +: 256]),
+		.INIT_A(INIT[10*256 +: 256]),
+		.INIT_B(INIT[11*256 +: 256]),
+		.INIT_C(INIT[12*256 +: 256]),
+		.INIT_D(INIT[13*256 +: 256]),
+		.INIT_E(INIT[14*256 +: 256]),
+		.INIT_F(INIT[15*256 +: 256]),
+		.INIT_10(INIT[16*256 +: 256]),
+		.INIT_11(INIT[17*256 +: 256]),
+		.INIT_12(INIT[18*256 +: 256]),
+		.INIT_13(INIT[19*256 +: 256])
+	) _TECHMAP_REPLACE_ (
+   		.WDATA(A1DATA),
+   		.WADDR(A1ADDR),
+   		.WE(A1EN),
+   		.WCLK(CLK2),
+   		.WCLKE(1'b1),
+   		.RDATA(B1DATA),
+   		.RADDR(B1ADDR),
+   		.RE(B1EN),
+   		.RCLK(CLK3)
+	);
+endmodule
diff --git a/techlibs/efinix/cells_map.v b/techlibs/efinix/cells_map.v
new file mode 100644
index 000000000..0aeab1902
--- /dev/null
+++ b/techlibs/efinix/cells_map.v
@@ -0,0 +1,45 @@
+module  \$_DFF_N_ (input D, C, output Q); EFX_FF #(.CLK_POLARITY(1'b0), .CE_POLARITY(1'b1), .SR_POLARITY(1'b1), .D_POLARITY(1'b1), .SR_SYNC(1'b1), .SR_VALUE(1'b0), .SR_SYNC_PRIORITY(1'b1)) _TECHMAP_REPLACE_ (.D(D), .CE(1'b1), .CLK(C), .SR(1'b0), .Q(Q)); endmodule
+module  \$_DFF_P_ (input D, C, output Q); EFX_FF #(.CLK_POLARITY(1'b1), .CE_POLARITY(1'b1), .SR_POLARITY(1'b1), .D_POLARITY(1'b1), .SR_SYNC(1'b1), .SR_VALUE(1'b0), .SR_SYNC_PRIORITY(1'b1)) _TECHMAP_REPLACE_ (.D(D), .CE(1'b1), .CLK(C), .SR(1'b0), .Q(Q)); endmodule
+
+module  \$_DFFE_NN_ (input D, C, E, output Q); EFX_FF #(.CLK_POLARITY(1'b0), .CE_POLARITY(1'b0), .SR_POLARITY(1'b1), .D_POLARITY(1'b1), .SR_SYNC(1'b1), .SR_VALUE(1'b0), .SR_SYNC_PRIORITY(1'b1)) _TECHMAP_REPLACE_ (.D(D), .CE(E), .CLK(C), .SR(1'b0), .Q(Q)); endmodule
+module  \$_DFFE_NP_ (input D, C, E, output Q); EFX_FF #(.CLK_POLARITY(1'b0), .CE_POLARITY(1'b1), .SR_POLARITY(1'b1), .D_POLARITY(1'b1), .SR_SYNC(1'b1), .SR_VALUE(1'b0), .SR_SYNC_PRIORITY(1'b1)) _TECHMAP_REPLACE_ (.D(D), .CE(E), .CLK(C), .SR(1'b0), .Q(Q)); endmodule
+
+module  \$_DFFE_PN_ (input D, C, E, output Q); EFX_FF #(.CLK_POLARITY(1'b1), .CE_POLARITY(1'b0), .SR_POLARITY(1'b1), .D_POLARITY(1'b1), .SR_SYNC(1'b1), .SR_VALUE(1'b0), .SR_SYNC_PRIORITY(1'b1)) _TECHMAP_REPLACE_ (.D(D), .CE(E), .CLK(C), .SR(1'b0), .Q(Q)); endmodule
+module  \$_DFFE_PP_ (input D, C, E, output Q); EFX_FF #(.CLK_POLARITY(1'b1), .CE_POLARITY(1'b1), .SR_POLARITY(1'b1), .D_POLARITY(1'b1), .SR_SYNC(1'b1), .SR_VALUE(1'b0), .SR_SYNC_PRIORITY(1'b1)) _TECHMAP_REPLACE_ (.D(D), .CE(E), .CLK(C), .SR(1'b0), .Q(Q)); endmodule
+
+module  \$_DFF_NN0_ (input D, C, R, output Q); EFX_FF #(.CLK_POLARITY(1'b0), .CE_POLARITY(1'b1), .SR_POLARITY(1'b0), .D_POLARITY(1'b1), .SR_SYNC(1'b0), .SR_VALUE(1'b0), .SR_SYNC_PRIORITY(1'b1)) _TECHMAP_REPLACE_ (.D(D), .CE(1'b1), .CLK(C), .SR(R), .Q(Q)); endmodule
+module  \$_DFF_NN1_ (input D, C, R, output Q); EFX_FF #(.CLK_POLARITY(1'b0), .CE_POLARITY(1'b1), .SR_POLARITY(1'b0), .D_POLARITY(1'b1), .SR_SYNC(1'b0), .SR_VALUE(1'b1), .SR_SYNC_PRIORITY(1'b1)) _TECHMAP_REPLACE_ (.D(D), .CE(1'b1), .CLK(C), .SR(R), .Q(Q)); endmodule
+module  \$_DFF_PN0_ (input D, C, R, output Q); EFX_FF #(.CLK_POLARITY(1'b1), .CE_POLARITY(1'b1), .SR_POLARITY(1'b0), .D_POLARITY(1'b1), .SR_SYNC(1'b0), .SR_VALUE(1'b0), .SR_SYNC_PRIORITY(1'b1)) _TECHMAP_REPLACE_ (.D(D), .CE(1'b1), .CLK(C), .SR(R), .Q(Q)); endmodule
+module  \$_DFF_PN1_ (input D, C, R, output Q); EFX_FF #(.CLK_POLARITY(1'b1), .CE_POLARITY(1'b1), .SR_POLARITY(1'b0), .D_POLARITY(1'b1), .SR_SYNC(1'b0), .SR_VALUE(1'b1), .SR_SYNC_PRIORITY(1'b1)) _TECHMAP_REPLACE_ (.D(D), .CE(1'b1), .CLK(C), .SR(R), .Q(Q)); endmodule
+
+module  \$_DFF_NP0_ (input D, C, R, output Q); EFX_FF #(.CLK_POLARITY(1'b0), .CE_POLARITY(1'b1), .SR_POLARITY(1'b1), .D_POLARITY(1'b1), .SR_SYNC(1'b0), .SR_VALUE(1'b0), .SR_SYNC_PRIORITY(1'b1)) _TECHMAP_REPLACE_ (.D(D), .CE(1'b1), .CLK(C), .SR(R), .Q(Q)); endmodule
+module  \$_DFF_NP1_ (input D, C, R, output Q); EFX_FF #(.CLK_POLARITY(1'b0), .CE_POLARITY(1'b1), .SR_POLARITY(1'b1), .D_POLARITY(1'b1), .SR_SYNC(1'b0), .SR_VALUE(1'b1), .SR_SYNC_PRIORITY(1'b1)) _TECHMAP_REPLACE_ (.D(D), .CE(1'b1), .CLK(C), .SR(R), .Q(Q)); endmodule
+module  \$_DFF_PP0_ (input D, C, R, output Q); EFX_FF #(.CLK_POLARITY(1'b1), .CE_POLARITY(1'b1), .SR_POLARITY(1'b1), .D_POLARITY(1'b1), .SR_SYNC(1'b0), .SR_VALUE(1'b0), .SR_SYNC_PRIORITY(1'b1)) _TECHMAP_REPLACE_ (.D(D), .CE(1'b1), .CLK(C), .SR(R), .Q(Q)); endmodule
+module  \$_DFF_PP1_ (input D, C, R, output Q); EFX_FF #(.CLK_POLARITY(1'b1), .CE_POLARITY(1'b1), .SR_POLARITY(1'b1), .D_POLARITY(1'b1), .SR_SYNC(1'b0), .SR_VALUE(1'b1), .SR_SYNC_PRIORITY(1'b1)) _TECHMAP_REPLACE_ (.D(D), .CE(1'b1), .CLK(C), .SR(R), .Q(Q)); endmodule
+
+`ifndef NO_LUT
+module \$lut (A, Y);
+  parameter WIDTH = 0;
+  parameter LUT = 0;
+
+  input [WIDTH-1:0] A;
+  output Y;
+
+  generate
+    if (WIDTH == 1) begin
+      EFX_LUT4 #(.LUTMASK(LUT)) _TECHMAP_REPLACE_ (.O(Y), .I0(A[0]), .I1(1'b0), .I2(1'b0), .I3(1'b0));
+    end else
+    if (WIDTH == 2) begin
+      EFX_LUT4 #(.LUTMASK(LUT)) _TECHMAP_REPLACE_ (.O(Y), .I0(A[0]), .I1(A[1]), .I2(1'b0), .I3(1'b0));
+    end else
+    if (WIDTH == 3) begin
+      EFX_LUT4 #(.LUTMASK(LUT)) _TECHMAP_REPLACE_ (.O(Y), .I0(A[0]), .I1(A[1]), .I2(A[2]), .I3(1'b0));
+    end else
+    if (WIDTH == 4) begin
+      EFX_LUT4 #(.LUTMASK(LUT)) _TECHMAP_REPLACE_ (.O(Y), .I0(A[0]), .I1(A[1]), .I2(A[2]), .I3(A[3]));
+    end else begin
+      wire _TECHMAP_FAIL_ = 1;
+    end
+  endgenerate
+endmodule
+`endif
diff --git a/techlibs/efinix/cells_sim.v b/techlibs/efinix/cells_sim.v
new file mode 100644
index 000000000..8c8f6afaa
--- /dev/null
+++ b/techlibs/efinix/cells_sim.v
@@ -0,0 +1,107 @@
+module EFX_LUT4(
+   output O, 
+   input I0,
+   input I1,
+   input I2,
+   input I3
+);
+   parameter LUTMASK  = 16'h0000;
+endmodule
+
+module EFX_ADD(
+   output O,
+   output CO,
+   input I0,
+   input I1,
+   input CI
+);
+   parameter I0_POLARITY   = 1;
+   parameter I1_POLARITY   = 1;
+endmodule
+
+module EFX_FF(
+   output Q,
+   input D,
+   input CE,
+   input CLK,
+   input SR
+);
+   parameter CLK_POLARITY = 1;
+   parameter CE_POLARITY = 1;
+   parameter SR_POLARITY = 1;
+   parameter SR_SYNC = 0;
+   parameter SR_VALUE = 0;
+   parameter SR_SYNC_PRIORITY = 0;
+   parameter D_POLARITY = 1;
+endmodule
+
+module EFX_GBUFCE(
+   input CE,
+   input I,
+   output O
+);
+   parameter CE_POLARITY = 1'b1;
+endmodule
+
+module EFX_RAM_5K(
+   input [WRITE_WIDTH-1:0] WDATA,
+   input [WRITE_ADDR_WIDTH-1:0] WADDR,
+   input WE, 
+   input WCLK,
+   input WCLKE, 
+   output [READ_WIDTH-1:0] RDATA, 
+   input [READ_ADDR_WIDTH-1:0] RADDR,
+   input RE, 
+   input RCLK
+);
+   parameter READ_WIDTH = 20;
+   parameter WRITE_WIDTH = 20;
+   parameter OUTPUT_REG = 1'b0;
+   parameter RCLK_POLARITY  = 1'b1;
+   parameter RE_POLARITY    = 1'b1;
+   parameter WCLK_POLARITY  = 1'b1;
+   parameter WE_POLARITY    = 1'b1;
+   parameter WCLKE_POLARITY = 1'b1;
+   parameter WRITE_MODE = "READ_FIRST";
+   parameter INIT_0 = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_1 = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_2 = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_3 = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_4 = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_5 = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_6 = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_7 = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_8 = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_9 = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_A = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_B = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_C = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_D = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_E = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_F = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_10 = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_11 = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_12 = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+   parameter INIT_13 = 256'h0000000000000000000000000000000000000000000000000000000000000000;
+
+   localparam READ_ADDR_WIDTH = 
+			    (READ_WIDTH == 16) ? 8 :  // 256x16
+			    (READ_WIDTH == 8)  ? 9 :  // 512x8
+			    (READ_WIDTH == 4)  ? 10 : // 1024x4
+			    (READ_WIDTH == 2)  ? 11 : // 2048x2
+			    (READ_WIDTH == 1)  ? 12 : // 4096x1
+			    (READ_WIDTH == 20) ? 8 :  // 256x20
+			    (READ_WIDTH == 10) ? 9 :  // 512x10
+			    (READ_WIDTH == 5)  ? 10 : -1; // 1024x5
+   
+   localparam WRITE_ADDR_WIDTH = 
+			    (WRITE_WIDTH == 16) ? 8 :  // 256x16
+			    (WRITE_WIDTH == 8)  ? 9 :  // 512x8
+			    (WRITE_WIDTH == 4)  ? 10 : // 1024x4
+			    (WRITE_WIDTH == 2)  ? 11 : // 2048x2
+			    (WRITE_WIDTH == 1)  ? 12 : // 4096x1
+			    (WRITE_WIDTH == 20) ? 8 :  // 256x20
+			    (WRITE_WIDTH == 10) ? 9 :  // 512x10
+			    (WRITE_WIDTH == 5)  ? 10 : -1; // 1024x5
+   
+endmodule
\ No newline at end of file
diff --git a/techlibs/efinix/efinix_fixcarry.cc b/techlibs/efinix/efinix_fixcarry.cc
new file mode 100644
index 000000000..b7cd995b8
--- /dev/null
+++ b/techlibs/efinix/efinix_fixcarry.cc
@@ -0,0 +1,122 @@
+/*
+ *  yosys -- Yosys Open SYnthesis Suite
+ *
+ *  Copyright (C) 2019  Miodrag Milanovic <miodrag@symbioticeda.com>
+ *
+ *  Permission to use, copy, modify, and/or distribute this software for any
+ *  purpose with or without fee is hereby granted, provided that the above
+ *  copyright notice and this permission notice appear in all copies.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#include "kernel/yosys.h"
+#include "kernel/sigtools.h"
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+static SigBit get_bit_or_zero(const SigSpec &sig)
+{
+	if (GetSize(sig) == 0)
+		return State::S0;
+	return sig[0];
+}
+
+static void fix_carry_chain(Module *module)
+{
+	SigMap sigmap(module);
+
+	pool<SigBit> ci_bits;
+	dict<SigBit, SigBit> mapping_bits;
+
+	for (auto cell : module->cells())
+	{
+		if (cell->type == "\\EFX_ADD") {
+			SigBit bit_i0 = get_bit_or_zero(cell->getPort("\\I0"));
+			SigBit bit_i1 = get_bit_or_zero(cell->getPort("\\I1"));
+			if (bit_i0 == State::S0 && bit_i1== State::S0) {
+				SigBit bit_ci = get_bit_or_zero(cell->getPort("\\CI"));
+				SigBit bit_o = sigmap(cell->getPort("\\O"));
+				ci_bits.insert(bit_ci);				
+				mapping_bits[bit_ci] = bit_o;
+			}
+		}
+	}
+	
+	vector<Cell*> adders_to_fix_cells;
+	for (auto cell : module->cells())
+	{
+		if (cell->type == "\\EFX_ADD") {
+			SigBit bit_ci = get_bit_or_zero(cell->getPort("\\CI"));
+			SigBit bit_i0 = get_bit_or_zero(cell->getPort("\\I0"));
+			SigBit bit_i1 = get_bit_or_zero(cell->getPort("\\I1"));			
+			SigBit canonical_bit = sigmap(bit_ci);
+			if (!ci_bits.count(canonical_bit))
+				continue;			
+			if (bit_i0 == State::S0 && bit_i1== State::S0) 
+				continue;
+
+			adders_to_fix_cells.push_back(cell);
+			log("Found %s cell named %s with invalid CI signal.\n", log_id(cell->type), log_id(cell));
+		}
+	}
+
+	for (auto cell : adders_to_fix_cells)
+	{
+		SigBit bit_ci = get_bit_or_zero(cell->getPort("\\CI"));
+		SigBit canonical_bit = sigmap(bit_ci);
+		auto bit = mapping_bits.at(canonical_bit);
+		log("Fixing %s cell named %s breaking carry chain.\n", log_id(cell->type), log_id(cell));
+		Cell *c = module->addCell(NEW_ID, "\\EFX_ADD");
+		SigBit new_bit = module->addWire(NEW_ID);
+		c->setParam("\\I0_POLARITY", State::S1);
+		c->setParam("\\I1_POLARITY", State::S1);
+		c->setPort("\\I0", bit);
+		c->setPort("\\I1", State::S1);
+		c->setPort("\\CI", State::S0);
+		c->setPort("\\CO", new_bit);
+		
+		cell->setPort("\\CI", new_bit);
+	}
+}
+
+struct EfinixCarryFixPass : public Pass {
+	EfinixCarryFixPass() : Pass("efinix_fixcarry", "Efinix: fix carry chain") { }
+	void help() YS_OVERRIDE
+	{
+		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+		log("\n");
+		log("    efinix_fixcarry [options] [selection]\n");
+		log("\n");
+		log("Add Efinix adders to fix carry chain if needed.\n");
+		log("\n");
+	}
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
+	{
+		log_header(design, "Executing efinix_fixcarry pass (fix invalid carry chain).\n");
+		
+		size_t argidx;
+		for (argidx = 1; argidx < args.size(); argidx++)
+		{
+			break;
+		}
+		extra_args(args, argidx, design);
+
+		Module *module = design->top_module();
+
+		if (module == nullptr)
+			log_cmd_error("No top module found.\n");
+
+		fix_carry_chain(module);		
+	}
+} EfinixCarryFixPass;
+
+PRIVATE_NAMESPACE_END
diff --git a/techlibs/efinix/efinix_gbuf.cc b/techlibs/efinix/efinix_gbuf.cc
new file mode 100644
index 000000000..e75fb3f4d
--- /dev/null
+++ b/techlibs/efinix/efinix_gbuf.cc
@@ -0,0 +1,119 @@
+/*
+ *  yosys -- Yosys Open SYnthesis Suite
+ *
+ *  Copyright (C) 2019  Miodrag Milanovic <miodrag@symbioticeda.com>
+ *  Copyright (C) 2012  Clifford Wolf <clifford@clifford.at>
+ *
+ *  Permission to use, copy, modify, and/or distribute this software for any
+ *  purpose with or without fee is hereby granted, provided that the above
+ *  copyright notice and this permission notice appear in all copies.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#include "kernel/yosys.h"
+#include "kernel/sigtools.h"
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+static void handle_gbufs(Module *module)
+{
+	SigMap sigmap(module);
+
+	pool<SigBit> clk_bits;
+	dict<SigBit, SigBit> rewrite_bits;
+	vector<pair<Cell*, SigBit>> pad_bits;
+
+	for (auto cell : module->cells())
+	{
+		if (cell->type == "\\EFX_FF") {
+			for (auto bit : sigmap(cell->getPort("\\CLK")))
+				clk_bits.insert(bit);
+		}
+		if (cell->type == "\\EFX_RAM_5K") {
+			for (auto bit : sigmap(cell->getPort("\\RCLK")))
+				clk_bits.insert(bit);
+			for (auto bit : sigmap(cell->getPort("\\WCLK")))
+				clk_bits.insert(bit);
+		}
+	}
+
+	for (auto wire : vector<Wire*>(module->wires()))
+	{
+		if (!wire->port_input)
+			continue;
+
+		for (int index = 0; index < GetSize(wire); index++)
+		{
+			SigBit bit(wire, index);
+			SigBit canonical_bit = sigmap(bit);
+
+			if (!clk_bits.count(canonical_bit))
+				continue;
+
+			Cell *c = module->addCell(NEW_ID, "\\EFX_GBUFCE");
+			SigBit new_bit = module->addWire(NEW_ID);
+			c->setParam("\\CE_POLARITY", State::S1);
+			c->setPort("\\O", new_bit);
+			c->setPort("\\CE", State::S1);
+			pad_bits.push_back(make_pair(c, bit));
+			rewrite_bits[canonical_bit] = new_bit;
+
+			log("Added %s cell %s for port bit %s.\n", log_id(c->type), log_id(c), log_signal(bit));
+		}
+	}
+
+	auto rewrite_function = [&](SigSpec &s) {
+		for (auto &bit : s) {
+			SigBit canonical_bit = sigmap(bit);
+			if (rewrite_bits.count(canonical_bit))
+				bit = rewrite_bits.at(canonical_bit);
+		}
+	};
+
+	module->rewrite_sigspecs(rewrite_function);
+
+	for (auto &it : pad_bits)
+		it.first->setPort("\\I", it.second);
+}
+
+struct EfinixGbufPass : public Pass {
+	EfinixGbufPass() : Pass("efinix_gbuf", "Efinix: insert global clock buffers") { }
+	void help() YS_OVERRIDE
+	{
+		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+		log("\n");
+		log("    efinix_gbuf [options] [selection]\n");
+		log("\n");
+		log("Add Efinix global clock buffers to top module as needed.\n");
+		log("\n");
+	}
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
+	{
+		log_header(design, "Executing efinix_gbuf pass (insert global clock buffers).\n");
+		
+		size_t argidx;
+		for (argidx = 1; argidx < args.size(); argidx++)
+		{
+			break;
+		}
+		extra_args(args, argidx, design);
+
+		Module *module = design->top_module();
+
+		if (module == nullptr)
+			log_cmd_error("No top module found.\n");
+
+		handle_gbufs(module);		
+	}
+} EfinixGbufPass;
+
+PRIVATE_NAMESPACE_END
diff --git a/techlibs/efinix/synth_efinix.cc b/techlibs/efinix/synth_efinix.cc
new file mode 100644
index 000000000..26a8d4eda
--- /dev/null
+++ b/techlibs/efinix/synth_efinix.cc
@@ -0,0 +1,219 @@
+/*
+ *  yosys -- Yosys Open SYnthesis Suite
+ *
+ *  Copyright (C) 2019  Miodrag Milanovic <miodrag@symbioticeda.com>
+ *  Copyright (C) 2019  Clifford Wolf <clifford@clifford.at>
+ *
+ *  Permission to use, copy, modify, and/or distribute this software for any
+ *  purpose with or without fee is hereby granted, provided that the above
+ *  copyright notice and this permission notice appear in all copies.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ */
+
+#include "kernel/register.h"
+#include "kernel/celltypes.h"
+#include "kernel/rtlil.h"
+#include "kernel/log.h"
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+struct SynthEfinixPass : public ScriptPass
+{
+	SynthEfinixPass() : ScriptPass("synth_efinix", "synthesis for Efinix FPGAs") { }
+
+	void help() YS_OVERRIDE
+	{
+		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+		log("\n");
+		log("    synth_efinix [options]\n");
+		log("\n");
+		log("This command runs synthesis for Efinix FPGAs.\n");
+		log("\n");
+		log("    -top <module>\n");
+		log("        use the specified module as top module\n");
+		log("\n");
+		log("    -edif <file>\n");
+		log("        write the design to the specified EDIF file. writing of an output file\n");
+		log("        is omitted if this parameter is not specified.\n");
+		log("\n");
+		log("    -json <file>\n");
+		log("        write the design to the specified JSON file. writing of an output file\n");
+		log("        is omitted if this parameter is not specified.\n");
+		log("\n");
+		log("    -run <from_label>:<to_label>\n");
+		log("        only run the commands between the labels (see below). an empty\n");
+		log("        from label is synonymous to 'begin', and empty to label is\n");
+		log("        synonymous to the end of the command list.\n");
+		log("\n");
+		log("    -noflatten\n");
+		log("        do not flatten design before synthesis\n");
+		log("\n");
+		log("    -retime\n");
+		log("        run 'abc' with -dff option\n");
+		log("\n");
+		log("\n");
+		log("The following commands are executed by this synthesis command:\n");
+		help_script();
+		log("\n");
+	}
+
+	string top_opt, edif_file, json_file;
+	bool flatten, retime;
+
+	void clear_flags() YS_OVERRIDE
+	{
+		top_opt = "-auto-top";
+		edif_file = "";
+		json_file = "";
+		flatten = true;
+		retime = false;
+	}
+
+	void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
+	{
+		string run_from, run_to;
+		clear_flags();
+
+		size_t argidx;
+		for (argidx = 1; argidx < args.size(); argidx++)
+		{
+			if (args[argidx] == "-top" && argidx+1 < args.size()) {
+				top_opt = "-top " + args[++argidx];
+				continue;
+			}
+			if (args[argidx] == "-edif" && argidx+1 < args.size()) {
+				edif_file = args[++argidx];
+				continue;
+			}
+			if (args[argidx] == "-json" && argidx+1 < args.size()) {
+				json_file = args[++argidx];
+				continue;
+			}
+			if (args[argidx] == "-run" && argidx+1 < args.size()) {
+				size_t pos = args[argidx+1].find(':');
+				if (pos == std::string::npos)
+					break;
+				run_from = args[++argidx].substr(0, pos);
+				run_to = args[argidx].substr(pos+1);
+				continue;
+			}
+			if (args[argidx] == "-noflatten") {
+				flatten = false;
+				continue;
+			}
+			if (args[argidx] == "-retime") {
+				retime = true;
+				continue;
+			}
+			break;
+		}
+		extra_args(args, argidx, design);
+
+		if (!design->full_selection())
+			log_cmd_error("This command only operates on fully selected designs!\n");
+
+		log_header(design, "Executing SYNTH_EFINIX pass.\n");
+		log_push();
+
+		run_script(design, run_from, run_to);
+
+		log_pop();
+	}
+
+	void script() YS_OVERRIDE
+	{
+		if (check_label("begin"))
+		{
+			run("read_verilog -lib +/efinix/cells_sim.v");
+			run(stringf("hierarchy -check %s", help_mode ? "-top <top>" : top_opt.c_str()));
+		}
+
+		if (flatten && check_label("flatten", "(unless -noflatten)"))
+		{
+			run("proc");
+			run("flatten");
+			run("tribuf -logic");
+			run("deminout");
+		}
+
+		if (check_label("coarse"))
+		{
+			run("synth -run coarse");
+		}
+
+		if (check_label("map_bram", "(skip if -nobram)"))
+		{
+			run("memory_bram -rules +/efinix/bram.txt");
+			run("techmap -map +/efinix/brams_map.v");
+			run("setundef -zero -params t:EFX_RAM_5K");
+		}
+
+		if (check_label("fine"))
+		{
+			run("opt -fast -mux_undef -undriven -fine");
+			run("memory_map");
+			run("opt -undriven -fine");
+			run("techmap -map +/techmap.v -map +/efinix/arith_map.v");
+			if (retime || help_mode)
+				run("abc -dff", "(only if -retime)");
+		}
+
+		if (check_label("map_ffs"))
+		{
+			run("dffsr2dff");
+			run("techmap -D NO_LUT -map +/efinix/cells_map.v");
+			run("dffinit -strinit SET RESET -ff AL_MAP_SEQ q REGSET -noreinit");
+			run("opt_expr -mux_undef");
+			run("simplemap");
+		}
+
+		if (check_label("map_luts"))
+		{
+			run("abc -lut 4");
+			run("clean");
+		}
+
+		if (check_label("map_cells"))
+		{
+			run("techmap -map +/efinix/cells_map.v");
+			run("clean");
+		}
+
+		if (check_label("map_gbuf"))
+		{
+			run("efinix_gbuf");
+			run("efinix_fixcarry");
+			run("clean");
+		}
+		
+		if (check_label("check"))
+		{
+			run("hierarchy -check");
+			run("stat");
+			run("check -noinit");
+		}
+
+		if (check_label("edif"))
+		{
+			if (!edif_file.empty() || help_mode)
+				run(stringf("write_edif %s", help_mode ? "<file-name>" : edif_file.c_str()));
+		}
+
+		if (check_label("json"))
+		{
+			if (!json_file.empty() || help_mode)
+				run(stringf("write_json %s", help_mode ? "<file-name>" : json_file.c_str()));
+		}
+	}
+} SynthEfinixPass;
+
+PRIVATE_NAMESPACE_END
diff --git a/techlibs/ice40/cells_sim.v b/techlibs/ice40/cells_sim.v
index 2205be27d..c7f3bdad2 100644
--- a/techlibs/ice40/cells_sim.v
+++ b/techlibs/ice40/cells_sim.v
@@ -141,8 +141,16 @@ module SB_CARRY (output CO, input I0, I1, CI);
 	assign CO = (I0 && I1) || ((I0 || I1) && CI);
 endmodule
 
-(* abc_box_id = 1, abc_carry="CI,CO", lib_whitebox *)
-module \$__ICE40_FULL_ADDER (output CO, O, input A, B, CI);
+(* abc_box_id = 1, lib_whitebox *)
+module \$__ICE40_FULL_ADDER (
+	(* abc_carry *)
+	output CO,
+	output O,
+	input A,
+	input B,
+	(* abc_carry *)
+	input CI
+);
 	SB_CARRY carry (
 		.I0(A),
 		.I1(B),
diff --git a/techlibs/xilinx/Makefile.inc b/techlibs/xilinx/Makefile.inc
index 2c6e7432e..2b1af289c 100644
--- a/techlibs/xilinx/Makefile.inc
+++ b/techlibs/xilinx/Makefile.inc
@@ -32,8 +32,8 @@ $(eval $(call add_share_file,share/xilinx,techlibs/xilinx/xc6s_brams_bb.v))
 $(eval $(call add_share_file,share/xilinx,techlibs/xilinx/xc7_brams.txt))
 $(eval $(call add_share_file,share/xilinx,techlibs/xilinx/xc7_brams_map.v))
 $(eval $(call add_share_file,share/xilinx,techlibs/xilinx/xc7_brams_bb.v))
-$(eval $(call add_share_file,share/xilinx,techlibs/xilinx/drams.txt))
-$(eval $(call add_share_file,share/xilinx,techlibs/xilinx/drams_map.v))
+$(eval $(call add_share_file,share/xilinx,techlibs/xilinx/lutrams.txt))
+$(eval $(call add_share_file,share/xilinx,techlibs/xilinx/lutrams_map.v))
 $(eval $(call add_share_file,share/xilinx,techlibs/xilinx/arith_map.v))
 $(eval $(call add_share_file,share/xilinx,techlibs/xilinx/ff_map.v))
 $(eval $(call add_share_file,share/xilinx,techlibs/xilinx/lut_map.v))
diff --git a/techlibs/xilinx/cells_sim.v b/techlibs/xilinx/cells_sim.v
index 05e46b4e7..973e17212 100644
--- a/techlibs/xilinx/cells_sim.v
+++ b/techlibs/xilinx/cells_sim.v
@@ -29,24 +29,35 @@ module GND(output G);
   assign G = 0;
 endmodule
 
-module IBUF(output O, input I);
+module IBUF(
+    output O,
+    (* iopad_external_pin *)
+    input I);
   parameter IOSTANDARD = "default";
   parameter IBUF_LOW_PWR = 0;
   assign O = I;
 endmodule
 
-module OBUF(output O, input I);
+module OBUF(
+    (* iopad_external_pin *)
+    output O,
+    input I);
   parameter IOSTANDARD = "default";
   parameter DRIVE = 12;
   parameter SLEW = "SLOW";
   assign O = I;
 endmodule
 
-module BUFG(output O, input I);
+module BUFG(
+    (* clkbuf_driver *)
+    output O,
+    input I);
+
   assign O = I;
 endmodule
 
 module BUFGCTRL(
+    (* clkbuf_driver *)
     output O,
     input I0, input I1,
     input S0, input S1,
@@ -72,7 +83,11 @@ assign O = S0_true ? I0_internal : (S1_true ? I1_internal : INIT_OUT);
 
 endmodule
 
-module BUFHCE(output O, input I, input CE);
+module BUFHCE(
+    (* clkbuf_driver *)
+    output O,
+    input I,
+    input CE);
 
 parameter [0:0] INIT_OUT = 1'b0;
 parameter CE_TYPE = "SYNC";
@@ -181,8 +196,16 @@ module XORCY(output O, input CI, LI);
   assign O = CI ^ LI;
 endmodule
 
-(* abc_box_id = 4, abc_carry="CI,CO", lib_whitebox *)
-module CARRY4(output [3:0] CO, O, input CI, CYINIT, input [3:0] DI, S);
+(* abc_box_id = 4, lib_whitebox *)
+module CARRY4(
+  (* abc_carry *)
+  output [3:0] CO,
+  output [3:0] O,
+  (* abc_carry *)
+  input        CI,
+  input        CYINIT,
+  input  [3:0] DI, S
+);
   assign O = S ^ {CO[2:0], CI | CYINIT};
   assign CO[0] = S[0] ? CI | CYINIT : DI[0];
   assign CO[1] = S[1] ? CO[0] : DI[1];
@@ -213,7 +236,7 @@ endmodule
 
 `endif
 
-module FDRE (output reg Q, input C, CE, D, R);
+module FDRE (output reg Q, (* clkbuf_sink *) input C, input CE, D, R);
   parameter [0:0] INIT = 1'b0;
   parameter [0:0] IS_C_INVERTED = 1'b0;
   parameter [0:0] IS_D_INVERTED = 1'b0;
@@ -225,7 +248,7 @@ module FDRE (output reg Q, input C, CE, D, R);
   endcase endgenerate
 endmodule
 
-module FDSE (output reg Q, input C, CE, D, S);
+module FDSE (output reg Q, (* clkbuf_sink *) input C, input CE, D, S);
   parameter [0:0] INIT = 1'b1;
   parameter [0:0] IS_C_INVERTED = 1'b0;
   parameter [0:0] IS_D_INVERTED = 1'b0;
@@ -237,7 +260,7 @@ module FDSE (output reg Q, input C, CE, D, S);
   endcase endgenerate
 endmodule
 
-module FDCE (output reg Q, input C, CE, D, CLR);
+module FDCE (output reg Q, (* clkbuf_sink *) input C, input CE, D, CLR);
   parameter [0:0] INIT = 1'b0;
   parameter [0:0] IS_C_INVERTED = 1'b0;
   parameter [0:0] IS_D_INVERTED = 1'b0;
@@ -251,7 +274,7 @@ module FDCE (output reg Q, input C, CE, D, CLR);
   endcase endgenerate
 endmodule
 
-module FDPE (output reg Q, input C, CE, D, PRE);
+module FDPE (output reg Q, (* clkbuf_sink *) input C, input CE, D, PRE);
   parameter [0:0] INIT = 1'b1;
   parameter [0:0] IS_C_INVERTED = 1'b0;
   parameter [0:0] IS_D_INVERTED = 1'b0;
@@ -265,34 +288,39 @@ module FDPE (output reg Q, input C, CE, D, PRE);
   endcase endgenerate
 endmodule
 
-module FDRE_1 (output reg Q, input C, CE, D, R);
+module FDRE_1 (output reg Q, (* clkbuf_sink *) input C, input CE, D, R);
   parameter [0:0] INIT = 1'b0;
   initial Q <= INIT;
   always @(negedge C) if (R) Q <= 1'b0; else if(CE) Q <= D;
 endmodule
 
-module FDSE_1 (output reg Q, input C, CE, D, S);
+module FDSE_1 (output reg Q, (* clkbuf_sink *) input C, input CE, D, S);
   parameter [0:0] INIT = 1'b1;
   initial Q <= INIT;
   always @(negedge C) if (S) Q <= 1'b1; else if(CE) Q <= D;
 endmodule
 
-module FDCE_1 (output reg Q, input C, CE, D, CLR);
+module FDCE_1 (output reg Q, (* clkbuf_sink *) input C, input CE, D, CLR);
   parameter [0:0] INIT = 1'b0;
   initial Q <= INIT;
   always @(negedge C, posedge CLR) if (CLR) Q <= 1'b0; else if (CE) Q <= D;
 endmodule
 
-module FDPE_1 (output reg Q, input C, CE, D, PRE);
+module FDPE_1 (output reg Q, (* clkbuf_sink *) input C, input CE, D, PRE);
   parameter [0:0] INIT = 1'b1;
   initial Q <= INIT;
   always @(negedge C, posedge PRE) if (PRE) Q <= 1'b1; else if (CE) Q <= D;
 endmodule
 
-(* abc_box_id = 5, abc_scc_break="D,WE" *)
+(* abc_box_id = 5 *)
 module RAM32X1D (
   output DPO, SPO,
-  input  D, WCLK, WE,
+  (* abc_scc_break *)
+  input  D,
+  (* clkbuf_sink *)
+  input  WCLK,
+  (* abc_scc_break *)
+  input  WE,
   input  A0, A1, A2, A3, A4,
   input  DPRA0, DPRA1, DPRA2, DPRA3, DPRA4
 );
@@ -307,10 +335,15 @@ module RAM32X1D (
   always @(posedge clk) if (WE) mem[a] <= D;
 endmodule
 
-(* abc_box_id = 6, abc_scc_break="D,WE" *)
+(* abc_box_id = 6 *)
 module RAM64X1D (
   output DPO, SPO,
-  input  D, WCLK, WE,
+  (* abc_scc_break *)
+  input  D,
+  (* clkbuf_sink *)
+  input  WCLK,
+  (* abc_scc_break *)
+  input  WE,
   input  A0, A1, A2, A3, A4, A5,
   input  DPRA0, DPRA1, DPRA2, DPRA3, DPRA4, DPRA5
 );
@@ -325,10 +358,15 @@ module RAM64X1D (
   always @(posedge clk) if (WE) mem[a] <= D;
 endmodule
 
-(* abc_box_id = 7, abc_scc_break="D,WE" *)
+(* abc_box_id = 7 *)
 module RAM128X1D (
   output       DPO, SPO,
-  input        D, WCLK, WE,
+  (* abc_scc_break *)
+  input        D,
+  (* clkbuf_sink *)
+  input        WCLK,
+  (* abc_scc_break *)
+  input        WE,
   input  [6:0] A, DPRA
 );
   parameter INIT = 128'h0;
@@ -342,19 +380,41 @@ endmodule
 
 module SRL16E (
   output Q,
+  (* clkbuf_sink *)
+  input CLK,
+  input A0, A1, A2, A3, CE, D
+);
+  parameter [15:0] INIT = 16'h0000;
+  parameter [0:0] IS_CLK_INVERTED = 1'b0;
+
+  reg [15:0] r = INIT;
+  assign Q = r[{A3,A2,A1,A0}];
+  generate
+    if (IS_CLK_INVERTED) begin
+      always @(negedge CLK) if (CE) r <= { r[14:0], D };
+    end
+    else
+      always @(posedge CLK) if (CE) r <= { r[14:0], D };
+  endgenerate
+endmodule
+
+module SRLC16E (
+  output Q,
+  output Q15,
   input A0, A1, A2, A3, CE, CLK, D
 );
   parameter [15:0] INIT = 16'h0000;
   parameter [0:0] IS_CLK_INVERTED = 1'b0;
 
   reg [15:0] r = INIT;
+  assign Q15 = r[15];
   assign Q = r[{A3,A2,A1,A0}];
   generate
     if (IS_CLK_INVERTED) begin
       always @(negedge CLK) if (CE) r <= { r[14:0], D };
     end
     else
-        always @(posedge CLK) if (CE) r <= { r[14:0], D };
+      always @(posedge CLK) if (CE) r <= { r[14:0], D };
   endgenerate
 endmodule
 
@@ -362,7 +422,9 @@ module SRLC32E (
   output Q,
   output Q31,
   input [4:0] A,
-  input CE, CLK, D
+  (* clkbuf_sink *)
+  input CLK,
+  input CE, D
 );
   parameter [31:0] INIT = 32'h00000000;
   parameter [0:0] IS_CLK_INVERTED = 1'b0;
diff --git a/techlibs/xilinx/cells_xtra.py b/techlibs/xilinx/cells_xtra.py
new file mode 100644
index 000000000..dd4e300ae
--- /dev/null
+++ b/techlibs/xilinx/cells_xtra.py
@@ -0,0 +1,257 @@
+#!/usr/bin/env python3
+
+from argparse import ArgumentParser
+from io import StringIO
+from enum import Enum, auto
+import os.path
+import sys
+
+
+class Cell:
+    def __init__(self, name, keep=False, port_attrs={}):
+        self.name = name
+        self.keep = keep
+        self.port_attrs = port_attrs
+
+
+CELLS = [
+    # Design elements types listed in Xilinx UG953
+    Cell('BSCANE2', keep=True),
+    # Cell('BUFG', port_attrs={'O': ['clkbuf_driver']}),
+    Cell('BUFGCE', port_attrs={'O': ['clkbuf_driver']}),
+    Cell('BUFGCE_1', port_attrs={'O': ['clkbuf_driver']}),
+    #Cell('BUFGCTRL', port_attrs={'O': ['clkbuf_driver']}),
+    Cell('BUFGMUX', port_attrs={'O': ['clkbuf_driver']}),
+    Cell('BUFGMUX_1', port_attrs={'O': ['clkbuf_driver']}),
+    Cell('BUFGMUX_CTRL', port_attrs={'O': ['clkbuf_driver']}),
+    Cell('BUFH', port_attrs={'O': ['clkbuf_driver']}),
+    #Cell('BUFHCE', port_attrs={'O': ['clkbuf_driver']}),
+    Cell('BUFIO', port_attrs={'O': ['clkbuf_driver']}),
+    Cell('BUFMR', port_attrs={'O': ['clkbuf_driver']}),
+    Cell('BUFMRCE', port_attrs={'O': ['clkbuf_driver']}),
+    Cell('BUFR', port_attrs={'O': ['clkbuf_driver']}),
+    Cell('CAPTUREE2', keep=True),
+    # Cell('CARRY4'),
+    Cell('CFGLUT5', port_attrs={'CLK': ['clkbuf_sink']}),
+    Cell('DCIRESET', keep=True),
+    Cell('DNA_PORT'),
+    Cell('DSP48E1', port_attrs={'CLK': ['clkbuf_sink']}),
+    Cell('EFUSE_USR'),
+    # Cell('FDCE'),
+    # Cell('FDPE'),
+    # Cell('FDRE'),
+    # Cell('FDSE'),
+    Cell('FIFO18E1', port_attrs={'RDCLK': ['clkbuf_sink'], 'WRCLK': ['clkbuf_sink']}),
+    Cell('FIFO36E1', port_attrs={'RDCLK': ['clkbuf_sink'], 'WRCLK': ['clkbuf_sink']}),
+    Cell('FRAME_ECCE2'),
+    Cell('GTHE2_CHANNEL'),
+    Cell('GTHE2_COMMON'),
+    Cell('GTPE2_CHANNEL'),
+    Cell('GTPE2_COMMON'),
+    Cell('GTXE2_CHANNEL'),
+    Cell('GTXE2_COMMON'),
+    # Cell('IBUF', port_attrs={'I': ['iopad_external_pin']}),
+    Cell('IBUF_IBUFDISABLE', port_attrs={'I': ['iopad_external_pin']}),
+    Cell('IBUF_INTERMDISABLE', port_attrs={'I': ['iopad_external_pin']}),
+    Cell('IBUFDS', port_attrs={'I': ['iopad_external_pin'], 'IB': ['iopad_external_pin']}),
+    Cell('IBUFDS_DIFF_OUT', port_attrs={'I': ['iopad_external_pin'], 'IB': ['iopad_external_pin']}),
+    Cell('IBUFDS_DIFF_OUT_IBUFDISABLE', port_attrs={'I': ['iopad_external_pin'], 'IB': ['iopad_external_pin']}),
+    Cell('IBUFDS_DIFF_OUT_INTERMDISABLE', port_attrs={'I': ['iopad_external_pin'], 'IB': ['iopad_external_pin']}),
+    Cell('IBUFDS_GTE2', port_attrs={'I': ['iopad_external_pin'], 'IB': ['iopad_external_pin']}),
+    Cell('IBUFDS_IBUFDISABLE', port_attrs={'I': ['iopad_external_pin'], 'IB': ['iopad_external_pin']}),
+    Cell('IBUFDS_INTERMDISABLE', port_attrs={'I': ['iopad_external_pin'], 'IB': ['iopad_external_pin']}),
+    Cell('IBUFG', port_attrs={'I': ['iopad_external_pin']}),
+    Cell('IBUFGDS', port_attrs={'I': ['iopad_external_pin'], 'IB': ['iopad_external_pin']}),
+    Cell('IBUFGDS_DIFF_OUT', port_attrs={'I': ['iopad_external_pin'], 'IB': ['iopad_external_pin']}),
+    Cell('ICAPE2', keep=True),
+    Cell('IDDR', port_attrs={'C': ['clkbuf_sink']}),
+    Cell('IDDR_2CLK', port_attrs={'C': ['clkbuf_sink'], 'CB': ['clkbuf_sink']}),
+    Cell('IDELAYCTRL', keep=True, port_attrs={'REFCLK': ['clkbuf_sink']}),
+    Cell('IDELAYE2', port_attrs={'C': ['clkbuf_sink']}),
+    Cell('IN_FIFO', port_attrs={'RDCLK': ['clkbuf_sink'], 'WRCLK': ['clkbuf_sink']}),
+    Cell('IOBUF', port_attrs={'IO': ['iopad_external_pin']}),
+    Cell('IOBUF_DCIEN', port_attrs={'IO': ['iopad_external_pin']}),
+    Cell('IOBUF_INTERMDISABLE', port_attrs={'IO': ['iopad_external_pin']}),
+    Cell('IOBUFDS', port_attrs={'IO': ['iopad_external_pin']}),
+    Cell('IOBUFDS_DCIEN', port_attrs={'IO': ['iopad_external_pin'], 'IOB': ['iopad_external_pin']}),
+    Cell('IOBUFDS_DIFF_OUT', port_attrs={'IO': ['iopad_external_pin'], 'IOB': ['iopad_external_pin']}),
+    Cell('IOBUFDS_DIFF_OUT_DCIEN', port_attrs={'IO': ['iopad_external_pin'], 'IOB': ['iopad_external_pin']}),
+    Cell('IOBUFDS_DIFF_OUT_INTERMDISABLE', port_attrs={'IO': ['iopad_external_pin'], 'IOB': ['iopad_external_pin']}),
+    Cell('ISERDESE2', port_attrs={
+        'CLK': ['clkbuf_sink'],
+        'CLKB': ['clkbuf_sink'],
+        'OCLK': ['clkbuf_sink'],
+        'OCLKB': ['clkbuf_sink'],
+        'CLKDIV': ['clkbuf_sink'],
+        'CLKDIVP': ['clkbuf_sink'],
+    }),
+    Cell('KEEPER'),
+    Cell('LDCE'),
+    Cell('LDPE'),
+    # Cell('LUT1'),
+    # Cell('LUT2'),
+    # Cell('LUT3'),
+    # Cell('LUT4'),
+    # Cell('LUT5'),
+    # Cell('LUT6'),
+    #Cell('LUT6_2'),
+    Cell('MMCME2_ADV'),
+    Cell('MMCME2_BASE'),
+    # Cell('MUXF7'),
+    # Cell('MUXF8'),
+    # Cell('OBUF', port_attrs={'O': ['iopad_external_pin']}),
+    Cell('OBUFDS', port_attrs={'O': ['iopad_external_pin'], 'OB': ['iopad_external_pin']}),
+    Cell('OBUFT', port_attrs={'O': ['iopad_external_pin']}),
+    Cell('OBUFTDS', port_attrs={'O': ['iopad_external_pin'], 'OB': ['iopad_external_pin']}),
+    Cell('ODDR', port_attrs={'C': ['clkbuf_sink']}),
+    Cell('ODELAYE2', port_attrs={'C': ['clkbuf_sink']}),
+    Cell('OSERDESE2', port_attrs={'CLK': ['clkbuf_sink'], 'CLKDIV': ['clkbuf_sink']}),
+    Cell('OUT_FIFO', port_attrs={'RDCLK': ['clkbuf_sink'], 'WRCLK': ['clkbuf_sink']}),
+    Cell('PHASER_IN'),
+    Cell('PHASER_IN_PHY'),
+    Cell('PHASER_OUT'),
+    Cell('PHASER_OUT_PHY'),
+    Cell('PHASER_REF'),
+    Cell('PHY_CONTROL'),
+    Cell('PLLE2_ADV'),
+    Cell('PLLE2_BASE'),
+    Cell('PS7', keep=True),
+    Cell('PULLDOWN'),
+    Cell('PULLUP'),
+    #Cell('RAM128X1D', port_attrs={'WCLK': ['clkbuf_sink']}),
+    Cell('RAM128X1S', port_attrs={'WCLK': ['clkbuf_sink']}),
+    Cell('RAM256X1S', port_attrs={'WCLK': ['clkbuf_sink']}),
+    Cell('RAM32M', port_attrs={'WCLK': ['clkbuf_sink']}),
+    #Cell('RAM32X1D', port_attrs={'WCLK': ['clkbuf_sink']}),
+    Cell('RAM32X1S', port_attrs={'WCLK': ['clkbuf_sink']}),
+    Cell('RAM32X1S_1', port_attrs={'WCLK': ['clkbuf_sink']}),
+    Cell('RAM32X2S', port_attrs={'WCLK': ['clkbuf_sink']}),
+    Cell('RAM64M', port_attrs={'WCLK': ['clkbuf_sink']}),
+    #Cell('RAM64X1D', port_attrs={'WCLK': ['clkbuf_sink']}),
+    Cell('RAM64X1S', port_attrs={'WCLK': ['clkbuf_sink']}),
+    Cell('RAM64X1S_1', port_attrs={'WCLK': ['clkbuf_sink']}),
+    Cell('RAM64X2S', port_attrs={'WCLK': ['clkbuf_sink']}),
+    # Cell('RAMB18E1', port_attrs={'CLKARDCLK': ['clkbuf_sink'], 'CLKBWRCLK': ['clkbuf_sink']}),
+    # Cell('RAMB36E1', port_attrs={'CLKARDCLK': ['clkbuf_sink'], 'CLKBWRCLK': ['clkbuf_sink']}),
+    Cell('ROM128X1'),
+    Cell('ROM256X1'),
+    Cell('ROM32X1'),
+    Cell('ROM64X1'),
+    #Cell('SRL16E', port_attrs={'CLK': ['clkbuf_sink']}),
+    #Cell('SRLC32E', port_attrs={'CLK': ['clkbuf_sink']}),
+    Cell('STARTUPE2', keep=True),
+    Cell('USR_ACCESSE2'),
+    Cell('XADC'),
+]
+
+class State(Enum):
+    OUTSIDE = auto()
+    IN_MODULE = auto()
+    IN_OTHER_MODULE = auto()
+    IN_FUNCTION = auto()
+    IN_TASK = auto()
+
+def xtract_cell_decl(cell, dirs, outf):
+    for dir in dirs:
+        fname = os.path.join(dir, cell.name + '.v')
+        try:
+            with open(fname) as f:
+                state = State.OUTSIDE
+                found = False
+                # Probably the most horrible Verilog "parser" ever written.
+                for l in f:
+                    l = l.partition('//')[0]
+                    l = l.strip()
+                    if l == 'module {}'.format(cell.name) or l.startswith('module {} '.format(cell.name)):
+                        if found:
+                            print('Multiple modules in {}.'.format(fname))
+                            sys.exit(1)
+                        elif state != State.OUTSIDE:
+                            print('Nested modules in {}.'.format(fname))
+                            sys.exit(1)
+                        found = True
+                        state = State.IN_MODULE
+                        if cell.keep:
+                            outf.write('(* keep *)\n')
+                        outf.write('module {} (...);\n'.format(cell.name))
+                    elif l.startswith('module '):
+                        if state != State.OUTSIDE:
+                            print('Nested modules in {}.'.format(fname))
+                            sys.exit(1)
+                        state = State.IN_OTHER_MODULE
+                    elif l.startswith('task '):
+                        if state == State.IN_MODULE:
+                            state = State.IN_TASK
+                    elif l.startswith('function '):
+                        if state == State.IN_MODULE:
+                            state = State.IN_FUNCTION
+                    elif l == 'endtask':
+                        if state == State.IN_TASK:
+                            state = State.IN_MODULE
+                    elif l == 'endfunction':
+                        if state == State.IN_FUNCTION:
+                            state = State.IN_MODULE
+                    elif l == 'endmodule':
+                        if state == State.IN_MODULE:
+                            outf.write(l + '\n')
+                            outf.write('\n')
+                        elif state != State.IN_OTHER_MODULE:
+                            print('endmodule in weird place in {}.'.format(cell.name, fname))
+                            sys.exit(1)
+                        state = State.OUTSIDE
+                    elif l.startswith(('input ', 'output ', 'inout ')) and state == State.IN_MODULE:
+                        if l.endswith((';', ',')):
+                            l = l[:-1]
+                        if ';' in l:
+                            print('Weird port line in {} [{}].'.format(fname, l))
+                            sys.exit(1)
+                        kind, _, ports = l.partition(' ')
+                        for port in ports.split(','):
+                            port = port.strip()
+                            for attr in cell.port_attrs.get(port, []):
+                                outf.write('    (* {} *)\n'.format(attr))
+                            outf.write('    {} {};\n'.format(kind, port))
+                    elif l.startswith('parameter ') and state == State.IN_MODULE:
+                        if 'UNPLACED' in l:
+                            continue
+                        if l.endswith((';', ',')):
+                            l = l[:-1]
+                        while '  ' in l:
+                            l = l.replace('  ', ' ')
+                        if ';' in l:
+                            print('Weird parameter line in {} [{}].'.format(fname, l))
+                            sys.exit(1)
+                        outf.write('    {};\n'.format(l))
+                if state != State.OUTSIDE:
+                    print('endmodule not found in {}.'.format(fname))
+                    sys.exit(1)
+                if not found:
+                    print('Cannot find module {} in {}.'.format(cell.name, fname))
+                    sys.exit(1)
+            return
+        except FileNotFoundError:
+            continue
+    print('Cannot find {}.'.format(cell.name))
+    sys.exit(1)
+
+if __name__ == '__main__':
+    parser = ArgumentParser(description='Extract Xilinx blackbox cell definitions from Vivado.')
+    parser.add_argument('vivado_dir', nargs='?', default='/opt/Xilinx/Vivado/2018.1')
+    args = parser.parse_args()
+
+    dirs = [
+        os.path.join(args.vivado_dir, 'data/verilog/src/xeclib'),
+        os.path.join(args.vivado_dir, 'data/verilog/src/retarget'),
+    ]
+    for dir in dirs:
+        if not os.path.isdir(dir):
+            print('{} is not a directory'.format(dir))
+
+    out = StringIO()
+    for cell in CELLS:
+        xtract_cell_decl(cell, dirs, out)
+
+    with open('cells_xtra.v', 'w') as f:
+        f.write('// Created by cells_xtra.py from Xilinx models\n')
+        f.write('\n')
+        f.write(out.getvalue())
diff --git a/techlibs/xilinx/cells_xtra.sh b/techlibs/xilinx/cells_xtra.sh
deleted file mode 100644
index 53b528820..000000000
--- a/techlibs/xilinx/cells_xtra.sh
+++ /dev/null
@@ -1,147 +0,0 @@
-#!/bin/bash
-
-set -e
-libdir="/opt/Xilinx/Vivado/2018.1/data/verilog/src"
-
-function xtract_cell_decl()
-{
-	for dir in $libdir/xeclib $libdir/retarget; do
-		[ -f $dir/$1.v ] || continue
-		[ -z "$2" ] || echo $2
-		egrep '^\s*((end)?module|parameter|input|inout|output|(end)?function|(end)?task)' $dir/$1.v |
-			sed -re '/UNPLACED/ d; /^\s*function/,/endfunction/ d; /^\s*task/,/endtask/ d;
-			         s,//.*,,; s/#?\(.*/(...);/; s/^(input|output|parameter)/ \1/;
-			         s/\s+$//; s/,$/;/; /input|output|parameter/ s/[^;]$/&;/; s/\s+/ /g;
-				 s/^ ((end)?module)/\1/; s/^ /    /; /module.*_bb/,/endmodule/ d;'
-		echo; return
-	done
-	echo "Can't find $1."
-	exit 1
-}
-
-{
-	echo "// Created by cells_xtra.sh from Xilinx models"
-	echo
-
-	# Design elements types listed in Xilinx UG953
-	xtract_cell_decl BSCANE2
-	# xtract_cell_decl BUFG
-	xtract_cell_decl BUFGCE
-	xtract_cell_decl BUFGCE_1
-	#xtract_cell_decl BUFGCTRL
-	xtract_cell_decl BUFGMUX
-	xtract_cell_decl BUFGMUX_1
-	xtract_cell_decl BUFGMUX_CTRL
-	xtract_cell_decl BUFH
-	#xtract_cell_decl BUFHCE
-	xtract_cell_decl BUFIO
-	xtract_cell_decl BUFMR
-	xtract_cell_decl BUFMRCE
-	xtract_cell_decl BUFR
-	xtract_cell_decl CAPTUREE2 "(* keep *)"
-	# xtract_cell_decl CARRY4
-	xtract_cell_decl CFGLUT5
-	xtract_cell_decl DCIRESET "(* keep *)"
-	xtract_cell_decl DNA_PORT
-	xtract_cell_decl DSP48E1
-	xtract_cell_decl EFUSE_USR
-	# xtract_cell_decl FDCE
-	# xtract_cell_decl FDPE
-	# xtract_cell_decl FDRE
-	# xtract_cell_decl FDSE
-	xtract_cell_decl FIFO18E1
-	xtract_cell_decl FIFO36E1
-	xtract_cell_decl FRAME_ECCE2
-	xtract_cell_decl GTHE2_CHANNEL
-	xtract_cell_decl GTHE2_COMMON
-	xtract_cell_decl GTPE2_CHANNEL
-	xtract_cell_decl GTPE2_COMMON
-	xtract_cell_decl GTXE2_CHANNEL
-	xtract_cell_decl GTXE2_COMMON
-	# xtract_cell_decl IBUF
-	xtract_cell_decl IBUF_IBUFDISABLE
-	xtract_cell_decl IBUF_INTERMDISABLE
-	xtract_cell_decl IBUFDS
-	xtract_cell_decl IBUFDS_DIFF_OUT
-	xtract_cell_decl IBUFDS_DIFF_OUT_IBUFDISABLE
-	xtract_cell_decl IBUFDS_DIFF_OUT_INTERMDISABLE
-	xtract_cell_decl IBUFDS_GTE2
-	xtract_cell_decl IBUFDS_IBUFDISABLE
-	xtract_cell_decl IBUFDS_INTERMDISABLE
-	xtract_cell_decl ICAPE2 "(* keep *)"
-	xtract_cell_decl IDDR
-	xtract_cell_decl IDDR_2CLK
-	xtract_cell_decl IDELAYCTRL "(* keep *)"
-	xtract_cell_decl IDELAYE2
-	xtract_cell_decl IN_FIFO
-	xtract_cell_decl IOBUF
-	xtract_cell_decl IOBUF_DCIEN
-	xtract_cell_decl IOBUF_INTERMDISABLE
-	xtract_cell_decl IOBUFDS
-	xtract_cell_decl IOBUFDS_DCIEN
-	xtract_cell_decl IOBUFDS_DIFF_OUT
-	xtract_cell_decl IOBUFDS_DIFF_OUT_DCIEN
-	xtract_cell_decl IOBUFDS_DIFF_OUT_INTERMDISABLE
-	xtract_cell_decl ISERDESE2
-	xtract_cell_decl KEEPER
-	xtract_cell_decl LDCE
-	xtract_cell_decl LDPE
-	# xtract_cell_decl LUT1
-	# xtract_cell_decl LUT2
-	# xtract_cell_decl LUT3
-	# xtract_cell_decl LUT4
-	# xtract_cell_decl LUT5
-	# xtract_cell_decl LUT6
-	#xtract_cell_decl LUT6_2
-	xtract_cell_decl MMCME2_ADV
-	xtract_cell_decl MMCME2_BASE
-	# xtract_cell_decl MUXF7
-	# xtract_cell_decl MUXF8
-	# xtract_cell_decl OBUF
-	xtract_cell_decl OBUFDS
-	xtract_cell_decl OBUFT
-	xtract_cell_decl OBUFTDS
-	xtract_cell_decl ODDR
-	xtract_cell_decl ODELAYE2
-	xtract_cell_decl OSERDESE2
-	xtract_cell_decl OUT_FIFO
-	xtract_cell_decl PHASER_IN
-	xtract_cell_decl PHASER_IN_PHY
-	xtract_cell_decl PHASER_OUT
-	xtract_cell_decl PHASER_OUT_PHY
-	xtract_cell_decl PHASER_REF
-	xtract_cell_decl PHY_CONTROL
-	xtract_cell_decl PLLE2_ADV
-	xtract_cell_decl PLLE2_BASE
-	xtract_cell_decl PS7 "(* keep *)"
-	xtract_cell_decl PULLDOWN
-	xtract_cell_decl PULLUP
-	#xtract_cell_decl RAM128X1D
-	xtract_cell_decl RAM128X1S
-	xtract_cell_decl RAM256X1S
-	xtract_cell_decl RAM32M
-	#xtract_cell_decl RAM32X1D
-	xtract_cell_decl RAM32X1S
-	xtract_cell_decl RAM32X1S_1
-	xtract_cell_decl RAM32X2S
-	xtract_cell_decl RAM64M
-	#xtract_cell_decl RAM64X1D
-	xtract_cell_decl RAM64X1S
-	xtract_cell_decl RAM64X1S_1
-	xtract_cell_decl RAM64X2S
-	# xtract_cell_decl RAMB18E1
-	# xtract_cell_decl RAMB36E1
-	xtract_cell_decl ROM128X1
-	xtract_cell_decl ROM256X1
-	xtract_cell_decl ROM32X1
-	xtract_cell_decl ROM64X1
-	#xtract_cell_decl SRL16E
-	#xtract_cell_decl SRLC32E
-	xtract_cell_decl STARTUPE2 "(* keep *)"
-	xtract_cell_decl USR_ACCESSE2
-	xtract_cell_decl XADC
-} > cells_xtra.new
-
-mv cells_xtra.new cells_xtra.v
-exit 0
-
diff --git a/techlibs/xilinx/cells_xtra.v b/techlibs/xilinx/cells_xtra.v
index 15fa1b63a..a6669b872 100644
--- a/techlibs/xilinx/cells_xtra.v
+++ b/techlibs/xilinx/cells_xtra.v
@@ -1,5 +1,6 @@
-// Created by cells_xtra.sh from Xilinx models
+// Created by cells_xtra.py from Xilinx models
 
+(* keep *)
 module BSCANE2 (...);
     parameter DISABLE_JTAG = "FALSE";
     parameter integer JTAG_CHAIN = 1;
@@ -20,29 +21,39 @@ module BUFGCE (...);
     parameter CE_TYPE = "SYNC";
     parameter [0:0] IS_CE_INVERTED = 1'b0;
     parameter [0:0] IS_I_INVERTED = 1'b0;
+    (* clkbuf_driver *)
     output O;
     input CE;
     input I;
 endmodule
 
 module BUFGCE_1 (...);
+    (* clkbuf_driver *)
     output O;
-    input CE, I;
+    input CE;
+    input I;
 endmodule
 
 module BUFGMUX (...);
     parameter CLK_SEL_TYPE = "SYNC";
+    (* clkbuf_driver *)
     output O;
-    input I0, I1, S;
+    input I0;
+    input I1;
+    input S;
 endmodule
 
 module BUFGMUX_1 (...);
     parameter CLK_SEL_TYPE = "SYNC";
+    (* clkbuf_driver *)
     output O;
-    input I0, I1, S;
+    input I0;
+    input I1;
+    input S;
 endmodule
 
 module BUFGMUX_CTRL (...);
+    (* clkbuf_driver *)
     output O;
     input I0;
     input I1;
@@ -50,16 +61,19 @@ module BUFGMUX_CTRL (...);
 endmodule
 
 module BUFH (...);
+    (* clkbuf_driver *)
     output O;
     input I;
 endmodule
 
 module BUFIO (...);
+    (* clkbuf_driver *)
     output O;
     input I;
 endmodule
 
 module BUFMR (...);
+    (* clkbuf_driver *)
     output O;
     input I;
 endmodule
@@ -68,12 +82,14 @@ module BUFMRCE (...);
     parameter CE_TYPE = "SYNC";
     parameter integer INIT_OUT = 0;
     parameter [0:0] IS_CE_INVERTED = 1'b0;
+    (* clkbuf_driver *)
     output O;
     input CE;
     input I;
 endmodule
 
 module BUFR (...);
+    (* clkbuf_driver *)
     output O;
     input CE;
     input CLR;
@@ -95,8 +111,15 @@ module CFGLUT5 (...);
     output CDO;
     output O5;
     output O6;
-    input I4, I3, I2, I1, I0;
-    input CDI, CE, CLK;
+    input I4;
+    input I3;
+    input I2;
+    input I1;
+    input I0;
+    input CDI;
+    input CE;
+    (* clkbuf_sink *)
+    input CLK;
 endmodule
 
 (* keep *)
@@ -108,7 +131,10 @@ endmodule
 module DNA_PORT (...);
     parameter [56:0] SIM_DNA_VALUE = 57'h0;
     output DOUT;
-    input CLK, DIN, READ, SHIFT;
+    input CLK;
+    input DIN;
+    input READ;
+    input SHIFT;
 endmodule
 
 module DSP48E1 (...);
@@ -175,6 +201,7 @@ module DSP48E1 (...);
     input CEINMODE;
     input CEM;
     input CEP;
+    (* clkbuf_sink *)
     input CLK;
     input [24:0] D;
     input [4:0] INMODE;
@@ -227,11 +254,13 @@ module FIFO18E1 (...);
     output WRERR;
     input [31:0] DI;
     input [3:0] DIP;
+    (* clkbuf_sink *)
     input RDCLK;
     input RDEN;
     input REGCE;
     input RST;
     input RSTREG;
+    (* clkbuf_sink *)
     input WRCLK;
     input WREN;
 endmodule
@@ -272,11 +301,13 @@ module FIFO36E1 (...);
     input [7:0] DIP;
     input INJECTDBITERR;
     input INJECTSBITERR;
+    (* clkbuf_sink *)
     input RDCLK;
     input RDEN;
     input REGCE;
     input RST;
     input RSTREG;
+    (* clkbuf_sink *)
     input WRCLK;
     input WREN;
 endmodule
@@ -1969,6 +2000,7 @@ module IBUF_IBUFDISABLE (...);
     parameter SIM_DEVICE = "7SERIES";
     parameter USE_IBUFDISABLE = "TRUE";
     output O;
+    (* iopad_external_pin *)
     input I;
     input IBUFDISABLE;
 endmodule
@@ -1979,6 +2011,7 @@ module IBUF_INTERMDISABLE (...);
     parameter SIM_DEVICE = "7SERIES";
     parameter USE_IBUFDISABLE = "TRUE";
     output O;
+    (* iopad_external_pin *)
     input I;
     input IBUFDISABLE;
     input INTERMDISABLE;
@@ -1993,7 +2026,10 @@ module IBUFDS (...);
     parameter IFD_DELAY_VALUE = "AUTO";
     parameter IOSTANDARD = "DEFAULT";
     output O;
-    input I, IB;
+    (* iopad_external_pin *)
+    input I;
+    (* iopad_external_pin *)
+    input IB;
 endmodule
 
 module IBUFDS_DIFF_OUT (...);
@@ -2001,8 +2037,12 @@ module IBUFDS_DIFF_OUT (...);
     parameter DQS_BIAS = "FALSE";
     parameter IBUF_LOW_PWR = "TRUE";
     parameter IOSTANDARD = "DEFAULT";
-    output O, OB;
-    input I, IB;
+    output O;
+    output OB;
+    (* iopad_external_pin *)
+    input I;
+    (* iopad_external_pin *)
+    input IB;
 endmodule
 
 module IBUFDS_DIFF_OUT_IBUFDISABLE (...);
@@ -2014,7 +2054,9 @@ module IBUFDS_DIFF_OUT_IBUFDISABLE (...);
     parameter USE_IBUFDISABLE = "TRUE";
     output O;
     output OB;
+    (* iopad_external_pin *)
     input I;
+    (* iopad_external_pin *)
     input IB;
     input IBUFDISABLE;
 endmodule
@@ -2028,7 +2070,9 @@ module IBUFDS_DIFF_OUT_INTERMDISABLE (...);
     parameter USE_IBUFDISABLE = "TRUE";
     output O;
     output OB;
+    (* iopad_external_pin *)
     input I;
+    (* iopad_external_pin *)
     input IB;
     input IBUFDISABLE;
     input INTERMDISABLE;
@@ -2041,7 +2085,9 @@ module IBUFDS_GTE2 (...);
     output O;
     output ODIV2;
     input CEB;
+    (* iopad_external_pin *)
     input I;
+    (* iopad_external_pin *)
     input IB;
 endmodule
 
@@ -2053,7 +2099,9 @@ module IBUFDS_IBUFDISABLE (...);
     parameter SIM_DEVICE = "7SERIES";
     parameter USE_IBUFDISABLE = "TRUE";
     output O;
+    (* iopad_external_pin *)
     input I;
+    (* iopad_external_pin *)
     input IB;
     input IBUFDISABLE;
 endmodule
@@ -2066,12 +2114,50 @@ module IBUFDS_INTERMDISABLE (...);
     parameter SIM_DEVICE = "7SERIES";
     parameter USE_IBUFDISABLE = "TRUE";
     output O;
+    (* iopad_external_pin *)
     input I;
+    (* iopad_external_pin *)
     input IB;
     input IBUFDISABLE;
     input INTERMDISABLE;
 endmodule
 
+module IBUFG (...);
+    parameter CAPACITANCE = "DONT_CARE";
+    parameter IBUF_DELAY_VALUE = "0";
+    parameter IBUF_LOW_PWR = "TRUE";
+    parameter IOSTANDARD = "DEFAULT";
+    output O;
+    (* iopad_external_pin *)
+    input I;
+endmodule
+
+module IBUFGDS (...);
+    parameter CAPACITANCE = "DONT_CARE";
+    parameter DIFF_TERM = "FALSE";
+    parameter IBUF_DELAY_VALUE = "0";
+    parameter IBUF_LOW_PWR = "TRUE";
+    parameter IOSTANDARD = "DEFAULT";
+    output O;
+    (* iopad_external_pin *)
+    input I;
+    (* iopad_external_pin *)
+    input IB;
+endmodule
+
+module IBUFGDS_DIFF_OUT (...);
+    parameter DIFF_TERM = "FALSE";
+    parameter DQS_BIAS = "FALSE";
+    parameter IBUF_LOW_PWR = "TRUE";
+    parameter IOSTANDARD = "DEFAULT";
+    output O;
+    output OB;
+    (* iopad_external_pin *)
+    input I;
+    (* iopad_external_pin *)
+    input IB;
+endmodule
+
 (* keep *)
 module ICAPE2 (...);
     parameter [31:0] DEVICE_ID = 32'h04244093;
@@ -2095,6 +2181,7 @@ module IDDR (...);
     parameter XON = "TRUE";
     output Q1;
     output Q2;
+    (* clkbuf_sink *)
     input C;
     input CE;
     input D;
@@ -2112,7 +2199,9 @@ module IDDR_2CLK (...);
     parameter SRTYPE = "SYNC";
     output Q1;
     output Q2;
+    (* clkbuf_sink *)
     input C;
+    (* clkbuf_sink *)
     input CB;
     input CE;
     input D;
@@ -2124,6 +2213,7 @@ endmodule
 module IDELAYCTRL (...);
     parameter SIM_DEVICE = "7SERIES";
     output RDY;
+    (* clkbuf_sink *)
     input REFCLK;
     input RST;
 endmodule
@@ -2143,6 +2233,7 @@ module IDELAYE2 (...);
     parameter integer SIM_DELAY_D = 0;
     output [4:0] CNTVALUEOUT;
     output DATAOUT;
+    (* clkbuf_sink *)
     input C;
     input CE;
     input CINVCTRL;
@@ -2174,9 +2265,11 @@ module IN_FIFO (...);
     output [7:0] Q7;
     output [7:0] Q8;
     output [7:0] Q9;
+    (* clkbuf_sink *)
     input RDCLK;
     input RDEN;
     input RESET;
+    (* clkbuf_sink *)
     input WRCLK;
     input WREN;
     input [3:0] D0;
@@ -2197,8 +2290,10 @@ module IOBUF (...);
     parameter IOSTANDARD = "DEFAULT";
     parameter SLEW = "SLOW";
     output O;
+    (* iopad_external_pin *)
     inout IO;
-    input I, T;
+    input I;
+    input T;
 endmodule
 
 module IOBUF_DCIEN (...);
@@ -2209,6 +2304,7 @@ module IOBUF_DCIEN (...);
     parameter SLEW = "SLOW";
     parameter USE_IBUFDISABLE = "TRUE";
     output O;
+    (* iopad_external_pin *)
     inout IO;
     input DCITERMDISABLE;
     input I;
@@ -2224,6 +2320,7 @@ module IOBUF_INTERMDISABLE (...);
     parameter SLEW = "SLOW";
     parameter USE_IBUFDISABLE = "TRUE";
     output O;
+    (* iopad_external_pin *)
     inout IO;
     input I;
     input IBUFDISABLE;
@@ -2238,8 +2335,11 @@ module IOBUFDS (...);
     parameter IOSTANDARD = "DEFAULT";
     parameter SLEW = "SLOW";
     output O;
-    inout IO, IOB;
-    input I, T;
+    (* iopad_external_pin *)
+    inout IO;
+    inout IOB;
+    input I;
+    input T;
 endmodule
 
 module IOBUFDS_DCIEN (...);
@@ -2251,7 +2351,9 @@ module IOBUFDS_DCIEN (...);
     parameter SLEW = "SLOW";
     parameter USE_IBUFDISABLE = "TRUE";
     output O;
+    (* iopad_external_pin *)
     inout IO;
+    (* iopad_external_pin *)
     inout IOB;
     input DCITERMDISABLE;
     input I;
@@ -2266,7 +2368,9 @@ module IOBUFDS_DIFF_OUT (...);
     parameter IOSTANDARD = "DEFAULT";
     output O;
     output OB;
+    (* iopad_external_pin *)
     inout IO;
+    (* iopad_external_pin *)
     inout IOB;
     input I;
     input TM;
@@ -2282,7 +2386,9 @@ module IOBUFDS_DIFF_OUT_DCIEN (...);
     parameter USE_IBUFDISABLE = "TRUE";
     output O;
     output OB;
+    (* iopad_external_pin *)
     inout IO;
+    (* iopad_external_pin *)
     inout IOB;
     input DCITERMDISABLE;
     input I;
@@ -2300,7 +2406,9 @@ module IOBUFDS_DIFF_OUT_INTERMDISABLE (...);
     parameter USE_IBUFDISABLE = "TRUE";
     output O;
     output OB;
+    (* iopad_external_pin *)
     inout IO;
+    (* iopad_external_pin *)
     inout IOB;
     input I;
     input IBUFDISABLE;
@@ -2348,15 +2456,21 @@ module ISERDESE2 (...);
     input BITSLIP;
     input CE1;
     input CE2;
+    (* clkbuf_sink *)
     input CLK;
+    (* clkbuf_sink *)
     input CLKB;
+    (* clkbuf_sink *)
     input CLKDIV;
+    (* clkbuf_sink *)
     input CLKDIVP;
     input D;
     input DDLY;
     input DYNCLKDIVSEL;
     input DYNCLKSEL;
+    (* clkbuf_sink *)
     input OCLK;
+    (* clkbuf_sink *)
     input OCLKB;
     input OFB;
     input RST;
@@ -2375,7 +2489,10 @@ module LDCE (...);
     parameter MSGON = "TRUE";
     parameter XON = "TRUE";
     output Q;
-    input CLR, D, G, GE;
+    input CLR;
+    input D;
+    input G;
+    input GE;
 endmodule
 
 module LDPE (...);
@@ -2385,7 +2502,10 @@ module LDPE (...);
     parameter MSGON = "TRUE";
     parameter XON = "TRUE";
     output Q;
-    input D, G, GE, PRE;
+    input D;
+    input G;
+    input GE;
+    input PRE;
 endmodule
 
 module MMCME2_ADV (...);
@@ -2533,7 +2653,10 @@ module OBUFDS (...);
     parameter CAPACITANCE = "DONT_CARE";
     parameter IOSTANDARD = "DEFAULT";
     parameter SLEW = "SLOW";
-    output O, OB;
+    (* iopad_external_pin *)
+    output O;
+    (* iopad_external_pin *)
+    output OB;
     input I;
 endmodule
 
@@ -2542,20 +2665,27 @@ module OBUFT (...);
     parameter integer DRIVE = 12;
     parameter IOSTANDARD = "DEFAULT";
     parameter SLEW = "SLOW";
+    (* iopad_external_pin *)
     output O;
-    input I, T;
+    input I;
+    input T;
 endmodule
 
 module OBUFTDS (...);
     parameter CAPACITANCE = "DONT_CARE";
     parameter IOSTANDARD = "DEFAULT";
     parameter SLEW = "SLOW";
-    output O, OB;
-    input I, T;
+    (* iopad_external_pin *)
+    output O;
+    (* iopad_external_pin *)
+    output OB;
+    input I;
+    input T;
 endmodule
 
 module ODDR (...);
     output Q;
+    (* clkbuf_sink *)
     input C;
     input CE;
     input D1;
@@ -2586,6 +2716,7 @@ module ODELAYE2 (...);
     parameter integer SIM_DELAY_D = 0;
     output [4:0] CNTVALUEOUT;
     output DATAOUT;
+    (* clkbuf_sink *)
     input C;
     input CE;
     input CINVCTRL;
@@ -2631,7 +2762,9 @@ module OSERDESE2 (...);
     output TBYTEOUT;
     output TFB;
     output TQ;
+    (* clkbuf_sink *)
     input CLK;
+    (* clkbuf_sink *)
     input CLKDIV;
     input D1;
     input D2;
@@ -2673,9 +2806,11 @@ module OUT_FIFO (...);
     output [3:0] Q9;
     output [7:0] Q5;
     output [7:0] Q6;
+    (* clkbuf_sink *)
     input RDCLK;
     input RDEN;
     input RESET;
+    (* clkbuf_sink *)
     input WRCLK;
     input WREN;
     input [7:0] D0;
@@ -3659,7 +3794,17 @@ module RAM128X1S (...);
     parameter [127:0] INIT = 128'h00000000000000000000000000000000;
     parameter [0:0] IS_WCLK_INVERTED = 1'b0;
     output O;
-    input A0, A1, A2, A3, A4, A5, A6, D, WCLK, WE;
+    input A0;
+    input A1;
+    input A2;
+    input A3;
+    input A4;
+    input A5;
+    input A6;
+    input D;
+    (* clkbuf_sink *)
+    input WCLK;
+    input WE;
 endmodule
 
 module RAM256X1S (...);
@@ -3668,6 +3813,7 @@ module RAM256X1S (...);
     output O;
     input [7:0] A;
     input D;
+    (* clkbuf_sink *)
     input WCLK;
     input WE;
 endmodule
@@ -3690,6 +3836,7 @@ module RAM32M (...);
     input [1:0] DIB;
     input [1:0] DIC;
     input [1:0] DID;
+    (* clkbuf_sink *)
     input WCLK;
     input WE;
 endmodule
@@ -3698,22 +3845,48 @@ module RAM32X1S (...);
     parameter [31:0] INIT = 32'h00000000;
     parameter [0:0] IS_WCLK_INVERTED = 1'b0;
     output O;
-    input A0, A1, A2, A3, A4, D, WCLK, WE;
+    input A0;
+    input A1;
+    input A2;
+    input A3;
+    input A4;
+    input D;
+    (* clkbuf_sink *)
+    input WCLK;
+    input WE;
 endmodule
 
 module RAM32X1S_1 (...);
     parameter [31:0] INIT = 32'h00000000;
     parameter [0:0] IS_WCLK_INVERTED = 1'b0;
     output O;
-    input A0, A1, A2, A3, A4, D, WCLK, WE;
+    input A0;
+    input A1;
+    input A2;
+    input A3;
+    input A4;
+    input D;
+    (* clkbuf_sink *)
+    input WCLK;
+    input WE;
 endmodule
 
 module RAM32X2S (...);
     parameter [31:0] INIT_00 = 32'h00000000;
     parameter [31:0] INIT_01 = 32'h00000000;
     parameter [0:0] IS_WCLK_INVERTED = 1'b0;
-    output O0, O1;
-    input A0, A1, A2, A3, A4, D0, D1, WCLK, WE;
+    output O0;
+    output O1;
+    input A0;
+    input A1;
+    input A2;
+    input A3;
+    input A4;
+    input D0;
+    input D1;
+    (* clkbuf_sink *)
+    input WCLK;
+    input WE;
 endmodule
 
 module RAM64M (...);
@@ -3734,6 +3907,7 @@ module RAM64M (...);
     input DIB;
     input DIC;
     input DID;
+    (* clkbuf_sink *)
     input WCLK;
     input WE;
 endmodule
@@ -3742,46 +3916,97 @@ module RAM64X1S (...);
     parameter [63:0] INIT = 64'h0000000000000000;
     parameter [0:0] IS_WCLK_INVERTED = 1'b0;
     output O;
-    input A0, A1, A2, A3, A4, A5, D, WCLK, WE;
+    input A0;
+    input A1;
+    input A2;
+    input A3;
+    input A4;
+    input A5;
+    input D;
+    (* clkbuf_sink *)
+    input WCLK;
+    input WE;
 endmodule
 
 module RAM64X1S_1 (...);
     parameter [63:0] INIT = 64'h0000000000000000;
     parameter [0:0] IS_WCLK_INVERTED = 1'b0;
     output O;
-    input A0, A1, A2, A3, A4, A5, D, WCLK, WE;
+    input A0;
+    input A1;
+    input A2;
+    input A3;
+    input A4;
+    input A5;
+    input D;
+    (* clkbuf_sink *)
+    input WCLK;
+    input WE;
 endmodule
 
 module RAM64X2S (...);
     parameter [63:0] INIT_00 = 64'h0000000000000000;
     parameter [63:0] INIT_01 = 64'h0000000000000000;
     parameter [0:0] IS_WCLK_INVERTED = 1'b0;
-    output O0, O1;
-    input A0, A1, A2, A3, A4, A5, D0, D1, WCLK, WE;
+    output O0;
+    output O1;
+    input A0;
+    input A1;
+    input A2;
+    input A3;
+    input A4;
+    input A5;
+    input D0;
+    input D1;
+    (* clkbuf_sink *)
+    input WCLK;
+    input WE;
 endmodule
 
 module ROM128X1 (...);
     parameter [127:0] INIT = 128'h00000000000000000000000000000000;
     output O;
-    input A0, A1, A2, A3, A4, A5, A6;
+    input A0;
+    input A1;
+    input A2;
+    input A3;
+    input A4;
+    input A5;
+    input A6;
 endmodule
 
 module ROM256X1 (...);
     parameter [255:0] INIT = 256'h0000000000000000000000000000000000000000000000000000000000000000;
     output O;
-    input A0, A1, A2, A3, A4, A5, A6, A7;
+    input A0;
+    input A1;
+    input A2;
+    input A3;
+    input A4;
+    input A5;
+    input A6;
+    input A7;
 endmodule
 
 module ROM32X1 (...);
     parameter [31:0] INIT = 32'h00000000;
     output O;
-    input A0, A1, A2, A3, A4;
+    input A0;
+    input A1;
+    input A2;
+    input A3;
+    input A4;
 endmodule
 
 module ROM64X1 (...);
     parameter [63:0] INIT = 64'h0000000000000000;
     output O;
-    input A0, A1, A2, A3, A4, A5;
+    input A0;
+    input A1;
+    input A2;
+    input A3;
+    input A4;
+    input A5;
 endmodule
 
 (* keep *)
diff --git a/techlibs/xilinx/drams.txt b/techlibs/xilinx/lutrams.txt
index 2613c206c..2613c206c 100644
--- a/techlibs/xilinx/drams.txt
+++ b/techlibs/xilinx/lutrams.txt
diff --git a/techlibs/xilinx/drams_map.v b/techlibs/xilinx/lutrams_map.v
index 77041ca86..77041ca86 100644
--- a/techlibs/xilinx/drams_map.v
+++ b/techlibs/xilinx/lutrams_map.v
diff --git a/techlibs/xilinx/synth_xilinx.cc b/techlibs/xilinx/synth_xilinx.cc
index d143c6823..f058da83d 100644
--- a/techlibs/xilinx/synth_xilinx.cc
+++ b/techlibs/xilinx/synth_xilinx.cc
@@ -63,14 +63,17 @@ struct SynthXilinxPass : public ScriptPass
 		log("        generate an output netlist (and BLIF file) suitable for VPR\n");
 		log("        (this feature is experimental and incomplete)\n");
 		log("\n");
+		log("    -ise\n");
+		log("        generate an output netlist suitable for ISE (enables -iopad)\n");
+		log("\n");
 		log("    -nobram\n");
-		log("        disable inference of block rams\n");
+		log("        do not use block RAM cells in output netlist\n");
 		log("\n");
-		log("    -nodram\n");
-		log("        disable inference of distributed rams\n");
+		log("    -nolutram\n");
+		log("        do not use distributed RAM cells in output netlist\n");
 		log("\n");
 		log("    -nosrl\n");
-		log("        disable inference of shift registers\n");
+		log("        do not use distributed SRL cells in output netlist\n");
 		log("\n");
 		log("    -nocarry\n");
 		log("        do not use XORCY/MUXCY/CARRY4 cells in output netlist\n");
@@ -78,6 +81,15 @@ struct SynthXilinxPass : public ScriptPass
 		log("    -nowidelut\n");
 		log("        do not use MUXF[78] resources to implement LUTs larger than LUT6s\n");
 		log("\n");
+		log("    -iopad\n");
+		log("        enable I/O buffer insertion (selected automatically by -ise)\n");
+		log("\n");
+		log("    -noiopad\n");
+		log("        disable I/O buffer insertion (only useful with -ise)\n");
+		log("\n");
+		log("    -noclkbuf\n");
+		log("        disable automatic clock buffer insertion\n");
+		log("\n");
 		log("    -widemux <int>\n");
 		log("        enable inference of hard multiplexer resources (MUXF[78]) for muxes at or\n");
 		log("        above this number of inputs (minimum value 2, recommended value >= 5).\n");
@@ -104,7 +116,8 @@ struct SynthXilinxPass : public ScriptPass
 	}
 
 	std::string top_opt, edif_file, blif_file, family;
-	bool flatten, retime, vpr, nobram, nodram, nosrl, nocarry, nowidelut, abc9;
+	bool flatten, retime, vpr, ise, iopad, noiopad, noclkbuf, nobram, nolutram, nosrl, nocarry, nowidelut, abc9;
+	bool flatten_before_abc;
 	int widemux;
 
 	void clear_flags() YS_OVERRIDE
@@ -116,13 +129,18 @@ struct SynthXilinxPass : public ScriptPass
 		flatten = false;
 		retime = false;
 		vpr = false;
+		ise = false;
+		iopad = false;
+		noiopad = false;
+		noclkbuf = false;
 		nocarry = false;
 		nobram = false;
-		nodram = false;
+		nolutram = false;
 		nosrl = false;
 		nocarry = false;
 		nowidelut = false;
 		abc9 = false;
+		flatten_before_abc = false;
 		widemux = 0;
 	}
 
@@ -162,6 +180,10 @@ struct SynthXilinxPass : public ScriptPass
 				flatten = true;
 				continue;
 			}
+			if (args[argidx] == "-flatten_before_abc") {
+				flatten_before_abc = true;
+				continue;
+			}
 			if (args[argidx] == "-retime") {
 				retime = true;
 				continue;
@@ -178,6 +200,22 @@ struct SynthXilinxPass : public ScriptPass
 				vpr = true;
 				continue;
 			}
+			if (args[argidx] == "-ise") {
+				ise = true;
+				continue;
+			}
+			if (args[argidx] == "-iopad") {
+				iopad = true;
+				continue;
+			}
+			if (args[argidx] == "-noiopad") {
+				noiopad = true;
+				continue;
+			}
+			if (args[argidx] == "-noclkbuf") {
+				noclkbuf = true;
+				continue;
+			}
 			if (args[argidx] == "-nocarry") {
 				nocarry = true;
 				continue;
@@ -186,8 +224,8 @@ struct SynthXilinxPass : public ScriptPass
 				nobram = true;
 				continue;
 			}
-			if (args[argidx] == "-nodram") {
-				nodram = true;
+			if (args[argidx] == "-nolutram" || /*deprecated alias*/ args[argidx] == "-nodram") {
+				nolutram = true;
 				continue;
 			}
 			if (args[argidx] == "-nosrl") {
@@ -284,7 +322,7 @@ struct SynthXilinxPass : public ScriptPass
 			run("opt_clean");
 		}
 
-		if (check_label("bram", "(skip if '-nobram')")) {
+		if (check_label("map_bram", "(skip if '-nobram')")) {
 			if (help_mode) {
 				run("memory_bram -rules +/xilinx/{family}_brams.txt");
 				run("techmap -map +/xilinx/{family}_brams_map.v");
@@ -301,20 +339,23 @@ struct SynthXilinxPass : public ScriptPass
 			}
 		}
 
-		if (check_label("dram", "(skip if '-nodram')")) {
-			if (!nodram || help_mode) {
-				run("memory_bram -rules +/xilinx/drams.txt");
-				run("techmap -map +/xilinx/drams_map.v");
+		if (check_label("map_lutram", "(skip if '-nolutram')")) {
+			if (!nolutram || help_mode) {
+				run("memory_bram -rules +/xilinx/lutrams.txt");
+				run("techmap -map +/xilinx/lutrams_map.v");
 			}
 		}
 
-		if (check_label("fine")) {
+		if (check_label("map_ffram")) {
 			if (widemux > 0)
 				run("opt -fast -mux_bool -undriven -fine"); // Necessary to omit -mux_undef otherwise muxcover
 									    // performs less efficiently
 			else
 				run("opt -fast -full");
 			run("memory_map");
+		}
+
+		if (check_label("fine")) {
 			run("dffsr2dff");
 			run("dff2dffe");
 			if (help_mode) {
@@ -382,6 +423,8 @@ struct SynthXilinxPass : public ScriptPass
 
 		if (check_label("map_luts")) {
 			run("opt_expr -mux_undef");
+			if (flatten_before_abc)
+				run("flatten");
 			if (help_mode)
 				run("abc -luts 2:2,3,6:5[,10,20] [-dff]", "(option for 'nowidelut', option for '-retime')");
 			else if (abc9) {
@@ -410,6 +453,18 @@ struct SynthXilinxPass : public ScriptPass
 			run("clean");
 		}
 
+		if (check_label("finalize")) {
+			bool do_iopad = iopad || (ise && !noiopad);
+			if (help_mode || !noclkbuf) {
+				if (help_mode || do_iopad)
+					run("clkbufmap -buf BUFG O:I -inpad IBUFG O:I", "(skip if '-noclkbuf', '-inpad' passed if '-iopad' or '-ise' and not '-noiopad')");
+				else
+					run("clkbufmap -buf BUFG O:I");
+			}
+			if (do_iopad)
+				run("iopadmap -bits -outpad OBUF I:O -inpad IBUF O:I A:top", "(only if '-iopad' or '-ise' and not '-noiopad')");
+		}
+
 		if (check_label("check")) {
 			run("hierarchy -check");
 			run("stat -tech xilinx");
diff --git a/techlibs/xilinx/xc6s_brams_bb.v b/techlibs/xilinx/xc6s_brams_bb.v
index eb1a29579..041d6b54f 100644
--- a/techlibs/xilinx/xc6s_brams_bb.v
+++ b/techlibs/xilinx/xc6s_brams_bb.v
@@ -1,5 +1,7 @@
 module RAMB8BWER (
+	(* clkbuf_sink *)
 	input CLKAWRCLK,
+	(* clkbuf_sink *)
 	input CLKBRDCLK,
 	input ENAWREN,
 	input ENBRDEN,
@@ -87,7 +89,9 @@ module RAMB8BWER (
 endmodule
 
 module RAMB16BWER (
+	(* clkbuf_sink *)
 	input CLKA,
+	(* clkbuf_sink *)
 	input CLKB,
 	input ENA,
 	input ENB,
diff --git a/techlibs/xilinx/xc7_brams_bb.v b/techlibs/xilinx/xc7_brams_bb.v
index a682ba4a7..a43b4b5a1 100644
--- a/techlibs/xilinx/xc7_brams_bb.v
+++ b/techlibs/xilinx/xc7_brams_bb.v
@@ -1,5 +1,7 @@
 module RAMB18E1 (
+	(* clkbuf_sink *)
 	input CLKARDCLK,
+	(* clkbuf_sink *)
 	input CLKBWRCLK,
 	input ENARDEN,
 	input ENBWREN,
@@ -123,7 +125,9 @@ module RAMB18E1 (
 endmodule
 
 module RAMB36E1 (
+	(* clkbuf_sink *)
 	input CLKARDCLK,
+	(* clkbuf_sink *)
 	input CLKBWRCLK,
 	input ENARDEN,
 	input ENBWREN,
diff --git a/tests/opt/opt_expr.ys b/tests/opt/opt_expr.ys
index f0306efa1..ecc2c8da8 100644
--- a/tests/opt/opt_expr.ys
+++ b/tests/opt/opt_expr.ys
@@ -221,3 +221,73 @@ check
 equiv_opt opt_expr -fine
 design -load postopt
 select -assert-count 1 t:$alu r:A_WIDTH=8 r:B_WIDTH=8 r:Y_WIDTH=9 %i %i %i
+
+###########
+
+design -reset
+read_verilog -icells <<EOT
+module opt_expr_shiftx_1bit(input [2:0] a, input [1:0] b, output y);
+    \$shiftx #(.A_SIGNED(0), .B_SIGNED(0), .A_WIDTH(4), .B_WIDTH(2), .Y_WIDTH(1)) shiftx (.A({1'bx,a}), .B(b), .Y(y));
+endmodule
+EOT
+check
+
+equiv_opt opt_expr
+design -load postopt
+select -assert-count 1 t:$shiftx r:A_WIDTH=3 %i
+
+###########
+
+design -reset
+read_verilog -icells <<EOT
+module opt_expr_shiftx_3bit(input [9:0] a, input [3:0] b, output [2:0] y);
+    \$shiftx #(.A_SIGNED(0), .B_SIGNED(0), .A_WIDTH(14), .B_WIDTH(4), .Y_WIDTH(3)) shiftx (.A({4'bxx00,a}), .B(b), .Y(y));
+endmodule
+EOT
+check
+
+equiv_opt opt_expr
+design -load postopt
+select -assert-count 1 t:$shiftx r:A_WIDTH=12 %i
+
+###########
+
+design -reset
+read_verilog -icells <<EOT
+module opt_expr_shift_1bit(input [2:0] a, input [1:0] b, output y);
+    \$shift #(.A_SIGNED(0), .B_SIGNED(0), .A_WIDTH(4), .B_WIDTH(2), .Y_WIDTH(1)) shift (.A({1'b0,a}), .B(b), .Y(y));
+endmodule
+EOT
+check
+
+equiv_opt opt_expr
+design -load postopt
+select -assert-count 1 t:$shift r:A_WIDTH=3 %i
+
+###########
+
+design -reset
+read_verilog -icells <<EOT
+module opt_expr_shift_3bit(input [9:0] a, input [3:0] b, output [2:0] y);
+    \$shift #(.A_SIGNED(0), .B_SIGNED(0), .A_WIDTH(14), .B_WIDTH(4), .Y_WIDTH(3)) shift (.A({4'b0x0x,a}), .B(b), .Y(y));
+endmodule
+EOT
+check
+
+equiv_opt opt_expr
+design -load postopt
+select -assert-count 1 t:$shift r:A_WIDTH=10 %i
+
+###########
+
+design -reset
+read_verilog -icells <<EOT
+module opt_expr_shift_3bit_keepdc(input [9:0] a, input [3:0] b, output [2:0] y);
+    \$shift #(.A_SIGNED(0), .B_SIGNED(0), .A_WIDTH(14), .B_WIDTH(4), .Y_WIDTH(3)) shift (.A({4'b0x0x,a}), .B(b), .Y(y));
+endmodule
+EOT
+check
+
+equiv_opt opt_expr -keepdc
+design -load postopt
+select -assert-count 1 t:$shift r:A_WIDTH=13 %i
diff --git a/tests/sat/initval.v b/tests/sat/initval.v
index 5b661f8d6..81f71b5ba 100644
--- a/tests/sat/initval.v
+++ b/tests/sat/initval.v
@@ -1,6 +1,7 @@
-module test(input clk, input [3:0] bar, output [3:0] foo);
+module test(input clk, input [3:0] bar, output [3:0] foo, asdf);
   reg [3:0] foo = 0;
   reg [3:0] last_bar = 0;
+  reg [3:0] asdf = 4'b1xxx;
 
   always @*
     foo[1:0] <= bar[1:0];
@@ -11,5 +12,10 @@ module test(input clk, input [3:0] bar, output [3:0] foo);
   always @(posedge clk)
     last_bar <= bar;
 
+  always @(posedge clk)
+    asdf[3] <= bar[3];
+  always @*
+    asdf[2:0] = 3'b111;
+
   assert property (foo == {last_bar[3:2], bar[1:0]});
 endmodule
diff --git a/tests/simple/realexpr.v b/tests/simple/realexpr.v
index 5b756e6be..74ed8faa5 100644
--- a/tests/simple/realexpr.v
+++ b/tests/simple/realexpr.v
@@ -1,4 +1,3 @@
-
 module demo_001(y1, y2, y3, y4);
 	output [7:0] y1, y2, y3, y4;
 
@@ -22,3 +21,13 @@ module demo_002(y0, y1, y2, y3);
 	assign y3 = 1 ? -1 : 'd0;
 endmodule
 
+module demo_003(output A, B);
+	parameter real p = 0;
+	assign A = (p==1.0);
+	assign B = (p!="1.000000");
+endmodule
+
+module demo_004(output A, B, C, D);
+	demo_003 #(1.0) demo_real (A, B);
+	demo_003 #(1) demo_int (C, D);
+endmodule
diff --git a/tests/techmap/.gitignore b/tests/techmap/.gitignore
index 397b4a762..cfed22fc5 100644
--- a/tests/techmap/.gitignore
+++ b/tests/techmap/.gitignore
@@ -1 +1,2 @@
 *.log
+/*.mk
diff --git a/tests/techmap/clkbufmap.ys b/tests/techmap/clkbufmap.ys
new file mode 100644
index 000000000..f1277864e
--- /dev/null
+++ b/tests/techmap/clkbufmap.ys
@@ -0,0 +1,96 @@
+read_verilog <<EOT
+module clkbuf (input i, (* clkbuf_driver *) output o); endmodule
+module dff ((* clkbuf_sink *) input clk, input d, output q); endmodule
+module dffe ((* clkbuf_sink *) input c, input d, e, output q); endmodule
+module latch (input e, d, output q); endmodule
+module clkgen (output o); endmodule
+
+module top(input clk1, clk2, clk3, d, e, output [4:0] q);
+wire clk4, clk5, clk6;
+dff s0 (.clk(clk1), .d(d), .q(q[0]));
+dffe s1 (.c(clk2), .d(d), .e(e), .q(q[1]));
+latch s2 (.e(clk3), .d(d), .q(q[2]));
+sub s3 (.sclk4(clk4), .sclk5(clk5), .sclk6(clk6), .sd(d), .sq(q[3]));
+dff s4 (.clk(clk4), .d(d), .q(q[4]));
+dff s5 (.clk(clk5), .d(d), .q(q[4]));
+dff s6 (.clk(clk6), .d(d), .q(q[4]));
+endmodule
+
+module sub(output sclk4, output sclk5, output sclk6, input sd, output sq);
+wire tmp;
+clkgen s7(.o(sclk4));
+clkgen s8(.o(sclk5));
+clkgen s9(.o(tmp));
+clkbuf s10(.i(tmp), .o(sclk6));
+dff s11(.clk(sclk4), .d(sd), .q(sq));
+endmodule
+EOT
+
+hierarchy -auto-top
+design -save ref
+
+# ----------------------
+
+design -load ref
+clkbufmap -buf clkbuf o:i
+select -assert-count 3 top/t:clkbuf
+select -assert-count 2 sub/t:clkbuf
+select -set clk1 w:clk1 %a %co t:clkbuf %i          # Find 'clk1' fanouts that are 'clkbuf'
+select -assert-count 1 @clk1                        # Check there is one such fanout
+select -assert-count 1 @clk1 %x:+[o] %co c:s* %i    # Check that the 'o' of that clkbuf drives one fanout
+select -assert-count 1 @clk1 %x:+[o] %co c:s0 %i    # And that one fanout is 's0'
+select -set clk2 w:clk2 %a %co t:clkbuf %i
+select -assert-count 1 @clk2
+select -assert-count 1 @clk2 %x:+[o] %co c:s* %i
+select -assert-count 1 @clk2 %x:+[o] %co c:s1 %i
+select -set clk5 w:clk5 %a %ci t:clkbuf %i
+select -assert-count 1 @clk5
+select -assert-count 1 @clk5 %x:+[o] %co c:s5 %i
+select -assert-count 1 @clk5 %x:+[i] %ci c:s3 %i
+select -set sclk4 w:sclk4 %a %ci t:clkbuf %i
+select -assert-count 1 @sclk4
+select -assert-count 1 @sclk4 %x:+[o] %co c:s11 %i
+select -assert-count 1 @sclk4 %x:+[i] %ci c:s7 %i
+
+# ----------------------
+
+design -load ref
+setattr -set clkbuf_inhibit 0 w:clk1
+setattr -set clkbuf_inhibit 1 w:clk2
+clkbufmap -buf clkbuf o:i
+select -assert-count 2 top/t:clkbuf
+select -set clk1 w:clk1 %a %co t:clkbuf %i          # Find 'clk1' fanouts that are 'clkbuf'
+select -assert-count 1 @clk1                        # Check there is one such fanout
+select -assert-count 1 @clk1 %x:+[o] %co c:s* %i    # Check that the 'o' of that clkbuf drives one fanout
+select -assert-count 1 @clk1 %x:+[o] %co c:s0 %i    # And that one fanout is 's0'
+select -assert-count 0 w:clk2 %a %co t:clkbuf %i
+
+# ----------------------
+
+design -load ref
+setattr -set clkbuf_inhibit 1 w:clk1
+setattr -set buffer_type "bufg" w:clk2
+clkbufmap -buf clkbuf o:i w:* a:buffer_type=none a:buffer_type=bufr %u %d
+select -assert-count 3 top/t:clkbuf
+select -assert-count 2 sub/t:clkbuf
+select -set clk1 w:clk1 %a %co t:clkbuf %i          # Find 'clk1' fanouts that are 'clkbuf'
+select -assert-count 1 @clk1                        # Check there is one such fanout
+select -assert-count 1 @clk1 %x:+[o] %co c:s* %i    # Check that the 'o' of that clkbuf drives one fanout
+select -assert-count 1 @clk1 %x:+[o] %co c:s0 %i    # And that one fanout is 's0'
+select -set clk2 w:clk2 %a %co t:clkbuf %i          # Find 'clk1' fanouts that are 'clkbuf'
+select -assert-count 1 @clk2                        # Check there is one such fanout
+select -assert-count 1 @clk2 %x:+[o] %co c:s* %i    # Check that the 'o' of that clkbuf drives one fanout
+select -assert-count 1 @clk2 %x:+[o] %co c:s1 %i    # And that one fanout is 's0'
+
+# ----------------------
+
+design -load ref
+setattr -set buffer_type "none" w:clk1
+setattr -set buffer_type "bufr" w:clk2
+setattr -set buffer_type "bufr" w:sclk4
+setattr -set buffer_type "bufr" w:sclk5
+clkbufmap -buf clkbuf o:i w:* a:buffer_type=none a:buffer_type=bufr %u %d
+select -assert-count 0 w:clk1 %a %co t:clkbuf %i
+select -assert-count 0 w:clk2 %a %co t:clkbuf %i
+select -assert-count 0 top/t:clkbuf
+select -assert-count 1 sub/t:clkbuf
diff --git a/tests/techmap/recursive.v b/tests/techmap/recursive.v
new file mode 100644
index 000000000..d281b21d8
--- /dev/null
+++ b/tests/techmap/recursive.v
@@ -0,0 +1,8 @@
+module top;
+sub s0();
+foo f0();
+endmodule
+
+module foo;
+sub s0();
+endmodule
diff --git a/tests/techmap/recursive_map.v b/tests/techmap/recursive_map.v
new file mode 100644
index 000000000..934256552
--- /dev/null
+++ b/tests/techmap/recursive_map.v
@@ -0,0 +1,4 @@
+module sub;
+    sub _TECHMAP_REPLACE_ ();
+    bar f0();
+endmodule
diff --git a/tests/techmap/recursive_runtest.sh b/tests/techmap/recursive_runtest.sh
new file mode 100644
index 000000000..30c79bf03
--- /dev/null
+++ b/tests/techmap/recursive_runtest.sh
@@ -0,0 +1,3 @@
+set -ev
+
+../../yosys -p 'hierarchy -top top; techmap -map recursive_map.v -max_iter 1; select -assert-count 2 t:sub; select -assert-count 2 t:bar' recursive.v
diff --git a/tests/techmap/run-test.sh b/tests/techmap/run-test.sh
index e2fc11e52..96489ff15 100755
--- a/tests/techmap/run-test.sh
+++ b/tests/techmap/run-test.sh
@@ -1,10 +1,20 @@
-#!/bin/bash
+#!/usr/bin/env bash
 set -e
-for x in *_runtest.sh; do
-	echo "Running $x.."
-	if ! bash $x &> ${x%.sh}.log; then
-		tail ${x%.sh}.log
-		echo ERROR
-		exit 1
+{
+echo "all::"
+for x in *.ys; do
+	echo "all:: run-$x"
+	echo "run-$x:"
+	echo "	@echo 'Running $x..'"
+	echo "	@../../yosys -ql ${x%.ys}.log $x"
+done
+for s in *.sh; do
+	if [ "$s" != "run-test.sh" ]; then
+		echo "all:: run-$s"
+		echo "run-$s:"
+		echo "	@echo 'Running $s..'"
+		echo "	@bash $s > ${s%.sh}.log 2>&1"
 	fi
 done
+} > run-test.mk
+exec ${MAKE:-make} -f run-test.mk
diff --git a/tests/various/mem2reg.ys b/tests/various/mem2reg.ys
new file mode 100644
index 000000000..85d6267c5
--- /dev/null
+++ b/tests/various/mem2reg.ys
@@ -0,0 +1,14 @@
+read_verilog <<EOT
+module top;
+parameter DATADEPTH=2;
+parameter DATAWIDTH=1;
+(* keep, nomem2reg *) reg [DATAWIDTH-1:0] data1 [DATADEPTH-1:0];
+(* keep, mem2reg *) reg [DATAWIDTH-1:0] data2 [DATADEPTH-1:0];
+endmodule
+EOT
+
+proc
+cd top
+select -assert-count 1 m:data1 a:src=<<EOT:4 %i
+select -assert-count 2 w:data2[*] a:src=<<EOT:5 %i
+select -assert-none a:mem2reg
diff --git a/tests/various/pmgen_reduce.ys b/tests/various/pmgen_reduce.ys
new file mode 100644
index 000000000..c214d3f25
--- /dev/null
+++ b/tests/various/pmgen_reduce.ys
@@ -0,0 +1,21 @@
+test_pmgen -generate reduce
+hierarchy -top pmtest_test_pmgen_pm_reduce
+flatten; opt_clean
+
+design -save gold
+test_pmgen -reduce_chain
+design -stash gate
+
+design -copy-from gold -as gold pmtest_test_pmgen_pm_reduce
+design -copy-from gate -as gate pmtest_test_pmgen_pm_reduce
+miter -equiv -flatten -make_assert gold gate miter
+sat -verify -prove-asserts miter
+
+design -load gold
+test_pmgen -reduce_tree
+design -stash gate
+
+design -copy-from gold -as gold pmtest_test_pmgen_pm_reduce
+design -copy-from gate -as gate pmtest_test_pmgen_pm_reduce
+miter -equiv -flatten -make_assert gold gate miter
+sat -verify -prove-asserts miter