Fix Decoder bug for constant 0 and DC (#2363) (#2371)

* Fix the QMC bug for constant and dontcare output.
* Fix the Espresso bug for constant and dontcare output.

(cherry picked from commit 46b53320e9ec09fc26d63259f1821f4234640839)

Co-authored-by: Jiuyang Liu <liu@jiuyang.me>

1 files changed, 35 insertions, 0 deletions

diff --git a/integration-tests/src/test/scala/chiselTests/util/experimental/minimizer/MinimizerSpec.scala b/integration-tests/src/test/scala/chiselTests/util/experimental/minimizer/MinimizerSpec.scala
index 07afd074..2d3e073c 100644
--- a/integration-tests/src/test/scala/chiselTests/util/experimental/minimizer/MinimizerSpec.scala
+++ b/integration-tests/src/test/scala/chiselTests/util/experimental/minimizer/MinimizerSpec.scala
@@ -272,4 +272,39 @@ trait MinimizerSpec extends AnyFlatSpec with ChiselScalatestTester with Formal {
       BitPat(s"b${Seq(N, X, X, X, X, X, X, X, X, A2_X, A1_X, IMM_X, DW_X, FN_X, N, M_X, X, X, X, X, X, X, X, CSR_X, X, X, X, X).reduce(_ + _)}")
     ))
   }
+
+  "output is 0" should "pass" in {
+    minimizerTest(TruthTable.fromString(
+      """00->0
+        |01->?
+        |10->0
+        |11->0
+        |    ?
+        |""".stripMargin
+
+    ))
+  }
+  "output is 1" should "pass" in {
+    minimizerTest(TruthTable.fromString(
+      """00->1
+        |01->?
+        |10->1
+        |11->1
+        |    ?
+        |""".stripMargin
+
+    ))
+  }
+  // I know this seems to be crazy, but if user is crazy as well...
+  "output is dont care" should "pass" in {
+    minimizerTest(TruthTable.fromString(
+      """00->?
+        |01->?
+        |10->?
+        |11->?
+        |    ?
+        |""".stripMargin
+
+    ))
+  }
 }