1 files changed, 103 insertions, 0 deletions
diff --git a/passes/sat/assertpmux.cc b/passes/sat/assertpmux.cc
new file mode 100644
index 000000000..3c8928db5
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+++ b/passes/sat/assertpmux.cc
@@ -0,0 +1,103 @@
+/*
+ *  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"
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+void assertpmux_worker(Cell *pmux, bool flag_noinit)
+{
+	Module *module = pmux->module;
+
+	log("Adding assert for $pmux cell %s.%s.\n", log_id(module), log_id(pmux));
+
+	int swidth = pmux->getParam("\\S_WIDTH").as_int();
+	int cntbits = ceil_log2(swidth+1);
+
+	SigSpec sel = pmux->getPort("\\S");
+	SigSpec cnt(State::S0, cntbits);
+
+	for (int i = 0; i < swidth; i++)
+		cnt = module->Add(NEW_ID, cnt, sel[i]);
+
+	SigSpec assert_a = module->Le(NEW_ID, cnt, SigSpec(1, cntbits));
+	SigSpec assert_en = State::S1;
+
+	if (flag_noinit) {
+		Cell *initstate_cell = module->addCell(NEW_ID, "$initstate");
+		SigSpec initstate_sig = module->addWire(NEW_ID);
+		initstate_cell->setPort("\\Y", initstate_sig);
+		assert_en = module->LogicNot(NEW_ID, initstate_sig);
+	}
+
+	Cell *assert_cell = module->addAssert(NEW_ID, assert_a, assert_en);
+
+	if (pmux->attributes.count("\\src") != 0)
+		assert_cell->attributes["\\src"] = pmux->attributes.at("\\src");
+}
+
+struct AssertpmuxPass : public Pass {
+	AssertpmuxPass() : Pass("assertpmux", "convert internal signals to module ports") { }
+	virtual void help()
+	{
+		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+		log("\n");
+		log("    assertpmux [options] [selection]\n");
+		log("\n");
+		log("This command adds asserts to the design that assert that all parallel muxes\n");
+		log("($pmux cells) have a maximum of one of their inputs enable at any time.\n");
+		log("\n");
+		log("    -noinit\n");
+		log("        do not enforce the pmux condition during the init state\n");
+		log("\n");
+	}
+	virtual void execute(std::vector<std::string> args, RTLIL::Design *design)
+	{
+		bool flag_noinit = false;
+
+		log_header(design, "Executing ASSERTPMUX pass (add asserts for $pmux cells).\n");
+
+		size_t argidx;
+		for (argidx = 1; argidx < args.size(); argidx++)
+		{
+			if (args[argidx] == "-noinit") {
+				flag_noinit = true;
+				continue;
+			}
+			break;
+		}
+		extra_args(args, argidx, design);
+
+		for (auto module : design->selected_modules())
+		{
+			vector<Cell*> pmux_cells;
+
+			for (auto cell : module->selected_cells())
+				if (cell->type == "$pmux")
+					pmux_cells.push_back(cell);
+
+			for (auto cell : pmux_cells)
+				assertpmux_worker(cell, flag_noinit);
+		}
+
+	}
+} AssertpmuxPass;
+
+PRIVATE_NAMESPACE_END