move datamerger proof into standard directory location (formal/),

update comments

diff --git a/src/soc/experiment/formal/proof_datamerger.py b/src/soc/experiment/formal/proof_datamerger.py
new file mode 100644 (file)
index 0000000..722c691
--- /dev/null
+++ b/src/soc/experiment/formal/proof_datamerger.py
@@ -0,0 +1,71 @@
+# Proof of correctness for DataMerger
+# Copyright (C) 2020 Michael Nolan <mtnolan2640@gmail.com>
+# Copyright (C) 2020 Tobias Platen <tplaten@posteo.de>
+
+from nmigen import (Module, Signal, Elaboratable, Mux, Cat, Repl,
+                    signed)
+from nmigen.asserts import Assert, AnyConst, AnySeq, Assume, Cover
+from nmutil.formaltest import FHDLTestCase
+from nmigen.cli import rtlil
+
+from soc.experiment.l0_cache import DataMerger
+
+import unittest
+
+
+# This defines a module to drive the device under test and assert
+# properties about its outputs
+class Driver(Elaboratable):
+    def __init__(self):
+        # inputs and outputs
+        pass
+
+    def elaborate(self, platform):
+        m = Module()
+        comb = m.d.comb
+
+        array_size = 8
+        m.submodules.dut = dut = DataMerger(array_size)
+
+        # assign anyseq to inputs
+        for j in range(dut.array_size):
+            comb += dut.addr_array_i[j].eq(AnyConst(dut.array_size))
+            comb += dut.data_i[j].eq(AnyConst(16+128))
+
+        allzero = 1
+        for j in range(dut.array_size):
+            allzero = (dut.addr_array_i[j] == 0) & allzero
+
+        with m.If(allzero):
+            # assert that the output is zero when the datamerger is idle
+            comb += Assert(dut.data_o == 0)
+        with m.Else():
+            comb += Assume(dut.data_o != 0) # at least one output bit is set
+            for j in range(dut.array_size):
+                for b in range(8):
+                    with m.If(dut.data_o.en[b]):
+                        comb += Assume(dut.data_i[j].en[b])
+                for b in range(128):
+                    with m.If(dut.data_o.data[b]):
+                        comb += Assume(dut.data_i[j].data[b])
+
+        return m
+
+
+class DataMergerTestCase(FHDLTestCase):
+    def test_formal(self):
+        module = Driver()
+        # bounded model check first
+        self.assertFormal(module, mode="bmc", depth=2)
+        # self.assertFormal(module, mode="cover", depth=2)     # case can happen
+        # XXX self.assertFormal(module, mode="prove")          # uses induction
+
+    def test_ilang(self):
+        dut = Driver()
+        vl = rtlil.convert(dut, ports=[])
+        with open("main_stage.il", "w") as f:
+            f.write(vl)
+
+
+if __name__ == '__main__':
+    unittest.main()

diff --git a/src/soc/experiment/proof_datamerger.py b/src/soc/experiment/proof_datamerger.py
deleted file mode 100644 (file)
index dd44449..0000000
--- a/src/soc/experiment/proof_datamerger.py
+++ /dev/null
@@ -1,71 +0,0 @@
-# Proof of correctness for partitioned equal signal combiner
-# Copyright (C) 2020 Michael Nolan <mtnolan2640@gmail.com>
-# Copyright (C) 2020 Tobias Platen <tplaten@posteo.de>
-
-from nmigen import (Module, Signal, Elaboratable, Mux, Cat, Repl,
-                    signed)
-from nmigen.asserts import Assert, AnyConst, AnySeq, Assume, Cover
-from nmutil.formaltest import FHDLTestCase
-from nmigen.cli import rtlil
-
-from soc.experiment.l0_cache import DataMerger
-
-import unittest
-
-
-# This defines a module to drive the device under test and assert
-# properties about its outputs
-class Driver(Elaboratable):
-    def __init__(self):
-        # inputs and outputs
-        pass
-
-    def elaborate(self, platform):
-        m = Module()
-        comb = m.d.comb
-
-        array_size = 8
-        m.submodules.dut = dut = DataMerger(array_size)
-
-        # assign anyseq to inputs
-        for j in range(dut.array_size):
-            comb += dut.addr_array_i[j].eq(AnyConst(dut.array_size))
-            comb += dut.data_i[j].eq(AnyConst(16+128))
-
-        allzero = 1
-        for j in range(dut.array_size):
-            allzero = (dut.addr_array_i[j] == 0) & allzero
-
-        # assert that the output is zero when the datamerger is idle
-        with m.If(allzero):
-            comb += Assert(dut.data_o == 0)
-        with m.Else():
-            comb += Assume(dut.data_o != 0) # at least one output bit is set
-            for j in range(dut.array_size):
-                for b in range(8):
-                    with m.If(dut.data_o.en[b]):
-                        comb += Assume(dut.data_i[j].en[b])
-                for b in range(128):
-                    with m.If(dut.data_o.data[b]):
-                        comb += Assume(dut.data_i[j].data[b])
-
-        return m
-
-
-class DataMergerTestCase(FHDLTestCase):
-    def test_formal(self):
-        module = Driver()
-        # bounded model check first
-        self.assertFormal(module, mode="bmc", depth=2)
-        # self.assertFormal(module, mode="cover", depth=2)     # case can happen
-        # XXX self.assertFormal(module, mode="prove")          # uses induction
-
-    def test_ilang(self):
-        dut = Driver()
-        vl = rtlil.convert(dut, ports=[])
-        with open("main_stage.il", "w") as f:
-            f.write(vl)
-
-
-if __name__ == '__main__':
-    unittest.main()