Support for inner classes, implicit parameter lists, supertypess

5 files changed, 165 insertions, 137 deletions

diff --git a/chiselFrontend/src/main/scala/chisel3/core/Aggregate.scala b/chiselFrontend/src/main/scala/chisel3/core/Aggregate.scala
index da14cefd..ed3e1fee 100644
--- a/chiselFrontend/src/main/scala/chisel3/core/Aggregate.scala
+++ b/chiselFrontend/src/main/scala/chisel3/core/Aggregate.scala
@@ -5,7 +5,6 @@ package chisel3.core
 import scala.collection.immutable.ListMap
 import scala.collection.mutable.{ArrayBuffer, HashSet, LinkedHashMap}
 import scala.language.experimental.macros
-import scala.util.Try
 
 import chisel3.internal._
 import chisel3.internal.Builder.pushCommand
@@ -558,131 +557,168 @@ class Bundle(implicit compileOptions: CompileOptions) extends Record {
   }
 
   override def cloneType : this.type = {
-    // Automatic Bundle cloning is inferred as follows:
-    // - User-overloaded cloneType is called instead of this (if supplied, so this method is never called)
-    // - Attempt to automatically fill in constructor parameters by using Scala reflection:
-    //   - If multiple constructors, error out
-    //   - If the constructor argument list can be matched to param accessors, call the constructor with
-    //     the result of those accessors
-    //   - Otherwise, error out
-    // - If Scala reflection crashes, fall back to Java reflection and inspect the constructor argument list:
-    //   - If no parameters, invoke constructor directly. That was easy!
-    //   - If the first parameter's type is equal to this Module, assume the Bundle is an inner class
-    //     and invoke it with the current containing Module
-    // - Error out to the user
-
-    def reflectError(desc: String) {
-      Builder.exception(s"Unable to automatically infer cloneType on $this: $desc")
+    // This attempts to infer constructor and arguments to clone this Bundle subtype without
+    // requiring the user explicitly overriding cloneType.
+
+    def reflectError(desc: String): Nothing = {
+      Builder.exception(s"Unable to automatically infer cloneType on $this: $desc").asInstanceOf[Nothing]
     }
 
-    // Check if the bundle is an instance of an inner class by examining
-    // whether it has one one-argument constructor taking a type matching the enclosing class
-    if (this.getClass.getConstructors.size == 1) {
-      val aggClass = this.getClass
-      val constr = aggClass.getConstructors.head
-      val argTypes = constr.getParameterTypes
-      val outerClass = aggClass.getEnclosingClass
-      if (argTypes.size == 1 && outerClass != null) {
-        // attempt to clone using "$outer"
-        var clone: Option[this.type] =
-          Try[this.type](constr.newInstance(aggClass.getDeclaredField("$outer").get(this)).asInstanceOf[this.type]).toOption
-        if (clone.isEmpty) {
-          // fall back to outerModule field
-          clone = Try[this.type](constr.newInstance(outerModule.get).asInstanceOf[this.type]).toOption
+    import scala.reflect.runtime.universe._
+
+    // Check if this is an inner class, and if so, try to get the outer instance
+    val clazz = this.getClass
+    val outerClassInstance = Option(clazz.getEnclosingClass) match {
+      case Some(outerClass) =>
+        val outerInstance = try {
+          clazz.getDeclaredField("$outer").get(this)  // doesn't work in all cases, namely anonymous inner Bundles
+        } catch {
+          case _: NoSuchFieldException => this.outerModule match {
+            case Some(outerModule) => outerModule
+            case None => reflectError(s"Unable to determine instance of outer class $outerClass")
+          }
         }
-        clone.foreach(_.outerModule = this.outerModule)
-        if (clone.isDefined) {
-          return clone.get
-        } else {
-          reflectError("non-trivial inner Bundle class")
+        if (!outerClass.isAssignableFrom(outerInstance.getClass)) {
+          reflectError(s"Automatically determined outer class instance $outerInstance not assignable to outer class $outerClass")
         }
-      }
+        Some(outerClass, outerInstance)
+      case None => None
     }
 
-    // Try Scala reflection
-    import scala.reflect.runtime.universe._
+    // If possible (constructor with no arguments), try Java reflection first
+    // This handles two cases that Scala reflection doesn't:
+    // 1. getting the ClassSymbol of a class with an anonymous outer class fails with a
+    //    CyclicReference exception
+    // 2. invoking the constructor of an anonymous inner class seems broken (it expects the outer
+    //    class as an argument, but fails because the number of arguments passed in is incorrect)
+    if (clazz.getConstructors.size == 1) {
+      var ctor = clazz.getConstructors.head
+      val argTypes = ctor.getParameterTypes.toList
+      val clone = (argTypes, outerClassInstance) match {
+        case (Nil, None) => // no arguments, no outer class, invoke constructor directly
+          Some(ctor.newInstance().asInstanceOf[this.type])
+        case (argType :: Nil, Some((_, outerInstance))) =>
+          if (argType isAssignableFrom outerInstance.getClass) {
+            Some(ctor.newInstance(outerInstance).asInstanceOf[this.type])
+          } else {
+            None
+          }
+        case _ => None
+      }
+      clone match {
+        case Some(clone) =>
+          clone.outerModule = this.outerModule
+          if (!clone.typeEquivalent(this)) {
+            reflectError(s"Automatically cloned $clone not type-equivalent to base $this." +
+            " Constructor argument values were not inferred, ensure constructor is deterministic.")
+          }
+          return clone.asInstanceOf[this.type]
+        case None =>
+      }
+    }
 
-    val mirror = runtimeMirror(this.getClass.getClassLoader)
-    val decls = mirror.classSymbol(this.getClass).typeSignature.decls
-    println(s"$this decls: $decls")
+    // Get constructor parameters and accessible fields
+    val mirror = runtimeMirror(clazz.getClassLoader)
+    val classSymbol = try {
+      mirror.reflect(this).symbol
+    } catch {
+      case e: scala.reflect.internal.Symbols#CyclicReference => reflectError(s"Scala cannot reflect on $this, got exception $e." +
+          " This is known to occur with inner classes on anonymous outer classes." +
+          " In those cases, autoclonetype only works with no-argument constructors, or you can define a custom cloneType.")
+    }
 
+    val decls = classSymbol.typeSignature.decls
     val ctors = decls.collect { case meth: MethodSymbol if meth.isConstructor => meth }
     if (ctors.size != 1) {
-      reflectError(s"found multiple constructors ($ctors). " +
-          "Either remove all but the default constructor, or define a custom cloneType method.")
+      reflectError(s"found multiple constructors ($ctors)." +
+          " Either remove all but the default constructor, or define a custom cloneType method.")
     }
-
-    val accessors = decls.collect { case meth: MethodSymbol if meth.isParamAccessor => meth }
-    val ctorParamss = ctors.head.paramLists
+    val ctor = ctors.head
+    val ctorParamss = ctor.paramLists
     val ctorParams = ctorParamss match {
       case Nil => List()
       case ctorParams :: Nil => ctorParams
+      case ctorParams :: ctorImplicits :: Nil => ctorParams ++ ctorImplicits
       case _ => reflectError(s"internal error, unexpected ctorParamss = $ctorParamss")
-          List()  // make the type system happy
     }
+    val ctorParamsNames = ctorParams.map(_.name.toString)
+
+    // Special case for anonymous inner classes: their constructor consists of just the outer class reference
+    // Scala reflection on anonymous inner class constructors seems broken
+    if (ctorParams.size == 1 && outerClassInstance.isDefined &&
+        ctorParams.head.typeSignature == mirror.classSymbol(outerClassInstance.get._1).toType) {
+      // Fall back onto Java reflection
+      val ctors = clazz.getConstructors
+      require(ctors.size == 1)  // should be consistent with Scala constructors
+      try {
+        val clone = ctors.head.newInstance(outerClassInstance.get._2).asInstanceOf[this.type]
+        clone.outerModule = this.outerModule
+        return clone
+      } catch {
+        case e @ (_: java.lang.reflect.InvocationTargetException | _: IllegalArgumentException) =>
+          reflectError(s"Unexpected failure at constructor invocation, got $e.")
+      }
+    }
+
+    // Get all the class symbols up to (but not including) Bundle and get all the accessors.
+    // (each ClassSymbol's decls only includes those declared in the class itself)
+    val bundleClassSymbol = mirror.classSymbol(classOf[Bundle])
+    val superClassSymbols = classSymbol.baseClasses.takeWhile(_ != bundleClassSymbol)
+    val superClassDecls = superClassSymbols.map(_.typeSignature.decls).flatten
+    val accessors = superClassDecls.collect { case meth: MethodSymbol if meth.isParamAccessor => meth }
 
+    // Get constructor argument values
     // Check that all ctor params are immutable and accessible. Immutability is required to avoid
     // potential subtle bugs (like values changing after cloning).
     // This also generates better error messages (all missing elements shown at once) instead of
     // failing at the use site one at a time.
-    val ctorParamsName = ctorParams.map(_.name.toString)
     val accessorsName = accessors.filter(_.isStable).map(_.name.toString)
-    val paramsDiff = ctorParamsName.toSet -- accessorsName.toSet
+    val paramsDiff = ctorParamsNames.toSet -- accessorsName.toSet
     if (!paramsDiff.isEmpty) {
-      reflectError(s"constructor has parameters ($paramsDiff) that are not both immutable and accessible." +
+      reflectError(s"constructor has parameters $paramsDiff that are not both immutable and accessible." +
           " Either make all parameters immutable and accessible (vals) so cloneType can be inferred, or define a custom cloneType method.")
     }
 
     // Get all the argument values
     val accessorsMap = accessors.map(accessor => accessor.name.toString -> accessor).toMap
     val instanceReflect = mirror.reflect(this)
-    val ctorParamsVals = ctorParamsName.map {
-      paramName => instanceReflect.reflectMethod(accessorsMap(paramName)).apply()
+    val ctorParamsNameVals = ctorParamsNames.map {
+      paramName => paramName -> instanceReflect.reflectMethod(accessorsMap(paramName)).apply()
+    }
+
+    // Oppurtunistic sanity check: ensure any arguments of type Data is not bound
+    // (which could lead to data conflicts, since it's likely the user didn't know to re-bind them).
+    // This is not guaranteed to catch all cases (for example, Data in Tuples or Iterables).
+    val boundDataParamNames = ctorParamsNameVals.map{ case (paramName, paramVal) => paramVal match {
+      case paramVal: Data => paramVal.hasBinding match {
+        case true => Some(paramName)
+        case false => None
+      }
+      case _ => None
+      }
+    }.filter(_.isDefined).map(_.get)
+    if (!boundDataParamNames.isEmpty) {
+      reflectError(s"constructor parameters ($boundDataParamNames) have values that are hardware types, which is likely to cause subtle errors." +
+          " Use chisel types instead: use the value before it is turned to a hardware type (with Wire(...), Reg(...), etc) or use chiselTypeOf(...) to extract the chisel type.")
     }
 
+    val ctorParamsVals = ctorParamsNameVals.map{ case (_, paramVal) => paramVal }
+
     // Invoke ctor
-    val classReflect = mirror.reflectClass(mirror.classSymbol(this.getClass))
-    classReflect.reflectConstructor(ctors.head).apply(ctorParamsVals:_*).asInstanceOf[this.type]
-
-
-
-//    val constructor = this.getClass.getConstructors.head
-//    val args = Seq.fill(constructor.getParameterTypes.size)(null)
-//    constructor.newInstance(args:_*).asInstanceOf[this.type]
-
-//    // If the user did not provide a cloneType method, try invoking one of
-//    // the following constructors, not all of which necessarily exist:
-//    // - A zero-parameter constructor
-//    // - A one-paramater constructor, with null as the argument
-//    // - A one-parameter constructor for a nested Bundle, with the enclosing
-//    //   parent Module as the argument
-//
-//
-//    // val classMirror = runtimeMirror.reflectClass(classSymbol)
-////    val constructors = classSymbol.typeSignature.members.filter(_.isConstructor).toList
-////    println(constructors)
-////
-//    val constructor = this.getClass.getConstructors.head
-//    println(constructor)
-//    println(constructor.getParameterTypes)
-//
-//    try {
-//      val args = Seq.fill(constructor.getParameterTypes.size)(null)
-//      constructor.newInstance(args:_*).asInstanceOf[this.type]
-//    } catch {
-//      case e: java.lang.reflect.InvocationTargetException if e.getCause.isInstanceOf[java.lang.NullPointerException] =>
-//        try {
-//          constructor.newInstance(_parent.get).asInstanceOf[this.type]
-//        } catch {
-//          case _: java.lang.reflect.InvocationTargetException | _: java.lang.IllegalArgumentException =>
-//            Builder.exception(s"Parameterized Bundle ${this.getClass} needs cloneType method. You are probably using " +
-//              "an anonymous Bundle object that captures external state and hence is un-cloneTypeable")
-//            this
-//        }
-//      case _: java.lang.reflect.InvocationTargetException | _: java.lang.IllegalArgumentException =>
-//        Builder.exception(s"Parameterized Bundle ${this.getClass} needs cloneType method")
-//        this
-//    }
+    val classMirror = outerClassInstance match {
+      case Some((_, outerInstance)) => mirror.reflect(outerInstance).reflectClass(classSymbol)
+      case None => mirror.reflectClass(classSymbol)
+    }
+    val clone = classMirror.reflectConstructor(ctor).apply(ctorParamsVals:_*).asInstanceOf[this.type]
+    clone.outerModule = this.outerModule
+
+    if (!clone.typeEquivalent(this)) {
+      reflectError(s"Automatically cloned $clone not type-equivalent to base $this." +
+          " Constructor argument values were inferred: ensure that variable names are consistent and have the same value throughout the constructor chain," +
+          " and that the constructor is deterministic.")
+    }
+
+    clone
   }
 
   /** Default "pretty-print" implementation
diff --git a/chiselFrontend/src/main/scala/chisel3/core/Binding.scala b/chiselFrontend/src/main/scala/chisel3/core/Binding.scala
index a6cc8bac..3fdc383c 100644
--- a/chiselFrontend/src/main/scala/chisel3/core/Binding.scala
+++ b/chiselFrontend/src/main/scala/chisel3/core/Binding.scala
@@ -23,7 +23,7 @@ object Binding {
 object requireIsHardware {
   def apply(node: Data, msg: String = "") = {
     node._parent match {  // Compatibility layer hack
-      case Some(x: BaseModule) => x._compatAutoWrapPorts
+      case Some(x: BaseModule) => x._autoWrapPorts
       case _ =>
     }
     if (!node.hasBinding) {
diff --git a/chiselFrontend/src/main/scala/chisel3/core/BlackBox.scala b/chiselFrontend/src/main/scala/chisel3/core/BlackBox.scala
index 3c99886e..aa0f8064 100644
--- a/chiselFrontend/src/main/scala/chisel3/core/BlackBox.scala
+++ b/chiselFrontend/src/main/scala/chisel3/core/BlackBox.scala
@@ -126,12 +126,12 @@ abstract class ExtModule(val params: Map[String, Param] = Map.empty[String, Para
   */
 abstract class BlackBox(val params: Map[String, Param] = Map.empty[String, Param])(implicit compileOptions: CompileOptions) extends BaseBlackBox {
   def io: Record
-  
+
   // Allow access to bindings from the compatibility package
-  protected def _compatIoPortBound() = portsContains(io)
-  
+  protected def _ioPortBound() = portsContains(io)
+
   private[core] override def generateComponent(): Component = {
-    _compatAutoWrapPorts()  // pre-IO(...) compatibility hack
+    _autoWrapPorts()  // pre-IO(...) compatibility hack
 
     // Restrict IO to just io, clock, and reset
     require(io != null, "BlackBox must have io")
diff --git a/chiselFrontend/src/main/scala/chisel3/core/Module.scala b/chiselFrontend/src/main/scala/chisel3/core/Module.scala
index 0c69010b..fa9ab082 100644
--- a/chiselFrontend/src/main/scala/chisel3/core/Module.scala
+++ b/chiselFrontend/src/main/scala/chisel3/core/Module.scala
@@ -191,7 +191,7 @@ abstract class BaseModule extends HasId {
     *
     * TODO: remove this, perhaps by removing Bindings checks in compatibility mode.
     */
-  def _compatAutoWrapPorts() {}
+  def _autoWrapPorts() {}
 
   //
   // BaseModule User API functions
@@ -200,10 +200,29 @@ abstract class BaseModule extends HasId {
     Builder.annotations += annotation
   }
 
-  /** Chisel2 code didn't require the IO(...) wrapper and would assign a Chisel type directly to
-    * io, then do operations on it. This binds a Chisel type in-place (mutably) as an IO. 
-    */
-  protected def _bindIoInPlace(iodef: Data) {
+  /**
+   * This must wrap the datatype used to set the io field of any Module.
+   * i.e. All concrete modules must have defined io in this form:
+   * [lazy] val io[: io type] = IO(...[: io type])
+   *
+   * Items in [] are optional.
+   *
+   * The granted iodef WILL NOT be cloned (to allow for more seamless use of
+   * anonymous Bundles in the IO) and thus CANNOT have been bound to any logic.
+   * This will error if any node is bound (e.g. due to logic in a Bundle
+   * constructor, which is considered improper).
+   *
+   * Also registers a Data as a port, also performing bindings. Cannot be called once ports are
+   * requested (so that all calls to ports will return the same information).
+   * Internal API.
+   *
+   * TODO(twigg): Specifically walk the Data definition to call out which nodes
+   * are problematic.
+   */
+  protected def IO[T<:Data](iodef: T): iodef.type = {
+    require(!_closed, "Can't add more ports after module close")
+    requireIsChiselType(iodef, "io type")
+
     // Compatibility code: Chisel2 did not require explicit direction on nodes
     // (unspecified treated as output, and flip on nothing was input).
     // This sets assigns the explicit directions required by newer semantics on
@@ -229,38 +248,11 @@ abstract class BaseModule extends HasId {
       }
     }
     assignCompatDir(iodef, false)
-    
+
+    // Bind each element of the iodef to being a Port
     iodef.bind(PortBinding(this))
     _ports += iodef
-  }
-      
-  /**
-   * This must wrap the datatype used to set the io field of any Module.
-   * i.e. All concrete modules must have defined io in this form:
-   * [lazy] val io[: io type] = IO(...[: io type])
-   *
-   * Items in [] are optional.
-   *
-   * The granted iodef WILL NOT be cloned (to allow for more seamless use of
-   * anonymous Bundles in the IO) and thus CANNOT have been bound to any logic.
-   * This will error if any node is bound (e.g. due to logic in a Bundle
-   * constructor, which is considered improper).
-   *
-   * Also registers a Data as a port, also performing bindings. Cannot be called once ports are
-   * requested (so that all calls to ports will return the same information).
-   * Internal API.
-   *
-   * TODO(twigg): Specifically walk the Data definition to call out which nodes
-   * are problematic.
-   */
-  protected def IO[T<:Data](iodef: T): iodef.type = {
-    require(!_closed, "Can't add more ports after module close")
-    requireIsChiselType(iodef, "io type")
-    
-    // Clone the IO so we preserve immutability of data types
-    val iodefClone = iodef.cloneTypeFull
-    _bindIoInPlace(iodefClone)
-    iodefClone.asInstanceOf[iodef.type]
+    iodef
   }
 
   //
diff --git a/chiselFrontend/src/main/scala/chisel3/core/UserModule.scala b/chiselFrontend/src/main/scala/chisel3/core/UserModule.scala
index ac87eda5..9c923037 100644
--- a/chiselFrontend/src/main/scala/chisel3/core/UserModule.scala
+++ b/chiselFrontend/src/main/scala/chisel3/core/UserModule.scala
@@ -151,8 +151,8 @@ abstract class LegacyModule(implicit moduleCompileOptions: CompileOptions)
   def io: Record
 
   // Allow access to bindings from the compatibility package
-  protected def _compatIoPortBound() = portsContains(io)
-  
+  protected def _ioPortBound() = portsContains(io)
+
   protected override def nameIds(rootClass: Class[_]): HashMap[HasId, String] = {
     val names = super.nameIds(rootClass)
 
@@ -165,7 +165,7 @@ abstract class LegacyModule(implicit moduleCompileOptions: CompileOptions)
   }
 
   private[core] override def generateComponent(): Component = {
-    _compatAutoWrapPorts()  // pre-IO(...) compatibility hack
+    _autoWrapPorts()  // pre-IO(...) compatibility hack
 
     // Restrict IO to just io, clock, and reset
     require(io != null, "Module must have io")