Merge pull request #3902 from YosysHQ/krys/yw_join

yosys-witness concat yw trace files

backends/smt2/witness.py

@@ -84,26 +84,65 @@ def stats(input):
 Transform a Yosys witness trace.
 
 Currently no transformations are implemented, so it is only useful for testing.
+If two or more inputs are provided they will be concatenated together into the output.
 """)
-@click.argument("input", type=click.File("r"))
+@click.argument("inputs", type=click.File("r"), nargs=-1)
 @click.argument("output", type=click.File("w"))
-def yw2yw(input, output):
-    click.echo(f"Copying yosys witness trace from {input.name!r} to {output.name!r}...")
-    inyw = ReadWitness(input)
+@click.option("--append", "-p", type=int, multiple=True,
+              help="Number of steps (+ve or -ve) to append to end of input trace. "
+                  +"Can be defined multiple times, following the same order as input traces. ")
+def yw2yw(inputs, output, append):
     outyw = WriteWitness(output, "yosys-witness yw2yw")
+    join_inputs = len(inputs) > 1
+    inyws = {}
 
-    for clock in inyw.clocks:
-        outyw.add_clock(clock["path"], clock["offset"], clock["edge"])
+    if not append:
+        # default to 0
+        append = [0] * len(inputs)
+    if len(append) != len(inputs):
+        print(f"Mismatch in number of --append values ({len(append)}) and input traces ({len(inputs)}).")
+        sys.exit(1)
 
-    for sig in inyw.signals:
-        outyw.add_sig(sig.path, sig.offset, sig.width, sig.init_only)
+    for (input, p) in zip(inputs, append):
+        if (join_inputs):
+            click.echo(f"Loading signals from yosys witness trace {input.name!r}...")
+        inyw = ReadWitness(input)
+        if p:
+            click.echo(f"  appending {p} steps")
+            if (p + len(inyw) <= 0):
+                click.echo(f"  skipping {input.name!r} (only {len(inyw)} steps to skip)")
+                continue
+            inyw.append_steps(p)
+        inyws[input] = inyw
+        for clock in inyw.clocks:
+            if clock not in outyw.clocks:
+                outyw.add_clock(clock["path"], clock["offset"], clock["edge"])
 
-    for t, values in inyw.steps():
-        outyw.step(values)
+        for sig in inyw.signals:
+            if sig not in outyw.signals:
+                outyw.add_sig(sig.path, sig.offset, sig.width, sig.init_only)
+
+    init_values = sum([inyw.init_step() for inyw in inyws.values()], start=WitnessValues())
+
+    first_witness = True
+    for (input, inyw) in inyws.items():
+        click.echo(f"Copying yosys witness trace from {input.name!r} to {output.name!r}...")
+
+        if first_witness:
+            outyw.step(init_values)
+        else:
+            outyw.step(inyw.first_step())
+
+        for t, values in inyw.steps(1):
+            outyw.step(values)
+
+        click.echo(f"  copied {t + 1} time steps.")
+        first_witness = False
 
     outyw.end_trace()
 
-    click.echo(f"Copied {outyw.t + 1} time steps.")
+    if join_inputs:
+        click.echo(f"Copied {outyw.t} total time steps.")
 
 
 class AigerMap: