BUGGY COMMIT: Shows MFC issue with multiple same bb paths

generators/chipyard/src/main/scala/example/GCD.scala

@@ -46,10 +46,11 @@ trait HasGCDIO extends BaseModule {
 }
 
 // DOC include start: GCD blackbox
-class GCDMMIOBlackBox(val w: Int) extends BlackBox(Map("WIDTH" -> IntParam(w))) with HasBlackBoxResource
+class GCDMMIOBlackBox(val w: Int) extends BlackBox(Map("WIDTH" -> IntParam(w))) with HasBlackBoxPath
   with HasGCDIO
 {
-  addResource("/vsrc/GCDMMIOBlackBox.v")
+  val chipyardDir = System.getProperty("user.dir")
+  addPath(s"$chipyardDir/generators/chipyard/src/main/resources/vsrc/GCDMMIOBlackBox.v")
 }
 // DOC include end: GCD blackbox
 
@@ -113,20 +114,36 @@ trait GCDModule extends HasRegMap {
     Module(new GCDMMIOChiselModule(params.width))
   }
 
+  val impl1 = if (params.useBlackBox) {
+    Module(new GCDMMIOBlackBox(params.width))
+  } else {
+    Module(new GCDMMIOChiselModule(params.width))
+  }
+
+
   impl.io.clock := clock
   impl.io.reset := reset.asBool
 
   impl.io.x := x
   impl.io.y := y.bits
   impl.io.input_valid := y.valid
-  y.ready := impl.io.input_ready
+  y.ready := impl.io.input_ready && impl1.io.input_ready
 
   gcd.bits := impl.io.gcd
-  gcd.valid := impl.io.output_valid
+  gcd.valid := impl.io.output_valid && impl1.io.output_valid
   impl.io.output_ready := gcd.ready
 
-  status := Cat(impl.io.input_ready, impl.io.output_valid)
+  status := Cat(impl.io.input_ready, impl.io.output_valid, impl1.io.input_ready, impl1.io.output_valid)
-  io.gcd_busy := impl.io.busy
+  io.gcd_busy := impl.io.busy && impl1.io.busy
+
+  impl1.io.clock := clock
+  impl1.io.reset := reset.asBool
+
+  impl1.io.x := x
+  impl1.io.y := y.bits
+  impl1.io.input_valid := y.valid
+
+  impl1.io.output_ready := gcd.ready
 
   regmap(
     0x00 -> Seq(