Add utility module for dealing with init attributes.

Makefile

@@ -585,6 +585,7 @@ $(eval $(call add_include_file,kernel/modtools.h))
 $(eval $(call add_include_file,kernel/macc.h))
 $(eval $(call add_include_file,kernel/utils.h))
 $(eval $(call add_include_file,kernel/satgen.h))
+$(eval $(call add_include_file,kernel/ffinit.h))
 $(eval $(call add_include_file,libs/ezsat/ezsat.h))
 $(eval $(call add_include_file,libs/ezsat/ezminisat.h))
 $(eval $(call add_include_file,libs/sha1/sha1.h))

kernel/ffinit.h

@@ -0,0 +1,146 @@
+/*
+ *  yosys -- Yosys Open SYnthesis Suite
+ *
+ *  Copyright (C) 2020  Marcelina Kościelnicka <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.
+ *
+ */
+
+#ifndef FFINIT_H
+#define FFINIT_H
+
+#include "kernel/yosys.h"
+#include "kernel/sigtools.h"
+
+YOSYS_NAMESPACE_BEGIN
+
+struct FfInitVals
+{
+	const SigMap *sigmap;
+	RTLIL::Module *module;
+	dict<SigBit, std::pair<State,SigBit>> initbits;
+
+	void set(const SigMap *sigmap_, RTLIL::Module *module)
+	{
+		sigmap = sigmap_;
+		initbits.clear();
+		for (auto wire : module->wires())
+		{
+			if (wire->attributes.count(ID::init) == 0)
+				continue;
+
+			SigSpec wirebits = (*sigmap)(wire);
+			Const initval = wire->attributes.at(ID::init);
+
+			for (int i = 0; i < GetSize(wirebits) && i < GetSize(initval); i++)
+			{
+				SigBit bit = wirebits[i];
+				State val = initval[i];
+
+				if (val != State::S0 && val != State::S1 && bit.wire != nullptr)
+					continue;
+
+				if (initbits.count(bit)) {
+					if (initbits.at(bit).first != val)
+						log_error("Conflicting init values for signal %s (%s = %s != %s).\n",
+								log_signal(bit), log_signal(SigBit(wire, i)),
+								log_signal(val), log_signal(initbits.at(bit).first));
+					continue;
+				}
+
+				initbits[bit] = std::make_pair(val,SigBit(wire,i));
+			}
+		}
+	}
+
+	RTLIL::State operator()(RTLIL::SigBit bit) const
+	{
+		auto it = initbits.find((*sigmap)(bit));
+		if (it != initbits.end())
+			return it->second.first;
+		else
+			return State::Sx;
+	}
+
+	RTLIL::Const operator()(const RTLIL::SigSpec &sig) const
+	{
+		RTLIL::Const res;
+		for (auto bit : sig)
+			res.bits.push_back((*this)(bit));
+		return res;
+	}
+
+	void set_init(RTLIL::SigBit bit, RTLIL::State val)
+	{
+		bit = (*sigmap)(bit);
+		auto it = initbits.find(bit);
+		if (it != initbits.end()) {
+			auto it2 = it->second.second.wire->attributes.find(ID::init);
+			it2->second[it->second.second.offset] = val;
+		} else {
+			log_assert(bit.wire);
+			initbits[bit] = std::make_pair(val,bit);
+			auto it2 = bit.wire->attributes.find(ID::init);
+			if (it2 != bit.wire->attributes.end()) {
+				it2->second[bit.offset] = val;
+			} else {
+				Const cval(State::Sx, GetSize(bit.wire));
+				cval[bit.offset] = val;
+				bit.wire->attributes[ID::init] = cval;
+			}
+		}
+	}
+
+	void set_init(const RTLIL::SigSpec &sig, RTLIL::Const val)
+	{
+		log_assert(GetSize(sig) == GetSize(val));
+		for (int i = 0; i < GetSize(sig); i++)
+			set_init(sig[i], val[i]);
+	}
+
+	void remove_init(RTLIL::SigBit bit)
+	{
+		auto it = initbits.find((*sigmap)(bit));
+		if (it != initbits.end()) {
+			auto it2 = it->second.second.wire->attributes.find(ID::init);
+			it2->second[it->second.second.offset] = State::Sx;
+			if (it2->second.is_fully_undef())
+				it->second.second.wire->attributes.erase(it2);
+			initbits.erase(it);
+		}
+	}
+
+	void remove_init(const RTLIL::SigSpec &sig)
+	{
+		for (auto bit : sig)
+			remove_init(bit);
+	}
+
+	void clear()
+	{
+		initbits.clear();
+	}
+
+	FfInitVals (const SigMap *sigmap, RTLIL::Module *module)
+	{
+		set(sigmap, module);
+	}
+
+	FfInitVals () {}
+};
+
+
+YOSYS_NAMESPACE_END
+
+#endif