From 99dad40ed056e33173be4cb24b476ae0ab28edc7 Mon Sep 17 00:00:00 2001
From: Robert Ou <rqou@robertou.com>
Date: Fri, 11 Aug 2017 02:00:33 -0700
Subject: [PATCH] recover_reduce: Add driver script for the $reduce_* recover
 feature

Conflicts:
	passes/techmap/Makefile.inc
---
 passes/techmap/Makefile.inc       |   1 +
 passes/techmap/recover_reduce.cpp | 100 ++++++++++++++++++++++++++++++
 2 files changed, 101 insertions(+)
 create mode 100644 passes/techmap/recover_reduce.cpp

diff --git a/passes/techmap/Makefile.inc b/passes/techmap/Makefile.inc
index 51ed356fe..7561369b9 100644
--- a/passes/techmap/Makefile.inc
+++ b/passes/techmap/Makefile.inc
@@ -17,6 +17,7 @@ OBJS += passes/techmap/iopadmap.o
 OBJS += passes/techmap/hilomap.o
 OBJS += passes/techmap/extract.o
 OBJS += passes/techmap/extract_fa.o
+OBJS += passes/techmap/recover_reduce.o
 OBJS += passes/techmap/recover_reduce_core.o
 OBJS += passes/techmap/alumacc.o
 OBJS += passes/techmap/dff2dffe.o
diff --git a/passes/techmap/recover_reduce.cpp b/passes/techmap/recover_reduce.cpp
new file mode 100644
index 000000000..21ebac532
--- /dev/null
+++ b/passes/techmap/recover_reduce.cpp
@@ -0,0 +1,100 @@
+/*
+ *  yosys -- Yosys Open SYnthesis Suite
+ *
+ *  Copyright (C) 2017 Robert Ou <rqou@robertou.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"
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+struct RecoverReducePass : public ScriptPass
+{
+    RecoverReducePass() : ScriptPass("recover_reduce", "recovers $reduce_* from gates") {}
+    virtual void help() YS_OVERRIDE
+    {
+        //   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+        log("\n");
+        log("    recover_reduce [options]\n");
+        log("\n");
+        log("recovers $reduce_* from gates\n");
+        log("\n");
+        log("Reconstructs $reduce_* elements (e.g. larger gates) given a netlist of gates.");
+        log("This pass is intended to be used as part of a circuit reverse-engineering workflow.\n");
+        log("\n");
+        log("\n");
+        log("The following commands are executed by this command:\n");
+        help_script();
+        log("\n");
+    }
+
+    bool one_pass, no_final_abc;
+
+    virtual void clear_flags() YS_OVERRIDE
+    {
+        one_pass = false;
+        no_final_abc = false;
+    }
+
+    virtual void execute(std::vector<std::string> args, RTLIL::Design *design) YS_OVERRIDE
+    {
+        clear_flags();
+
+        size_t argidx;
+        for (argidx = 1; argidx < args.size(); argidx++)
+        {
+            if (args[argidx] == "-one_pass") {
+                one_pass = true;
+                continue;
+            }
+            if (args[argidx] == "-no_final_abc") {
+                no_final_abc = true;
+                continue;
+            }
+            break;
+        }
+        extra_args(args, argidx, design);
+
+        log_header(design, "Executing recover_reduce.\n");
+        log_push();
+
+        run_script(design, "", "");
+
+        log_pop();
+    }
+
+    virtual void script() YS_OVERRIDE
+    {
+        if (!one_pass)
+        {
+            // Certain structures such as counters seem to work better if we extract only AND
+            // and then run a general extract pass.
+            // XXX: Why is that? Does this work in general?
+            run("abc -g AND");
+            run("recover_reduce_core");
+        }
+        run("abc -g AND,OR,XOR");
+        run("recover_reduce_core");
+
+        if (!no_final_abc)
+            run("abc");
+
+        run("clean");
+    }
+} RecoverReducePass;
+
+PRIVATE_NAMESPACE_END
-- 
2.30.2