1 files changed, 159 insertions, 0 deletions
diff --git a/chiselFrontend/src/main/scala/chisel3/core/Module.scala b/chiselFrontend/src/main/scala/chisel3/core/Module.scala
new file mode 100644
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--- /dev/null
+++ b/chiselFrontend/src/main/scala/chisel3/core/Module.scala
@@ -0,0 +1,159 @@
+// See LICENSE for license details.
+
+package chisel3.core
+
+import scala.collection.mutable.{ArrayBuffer, HashSet}
+import scala.language.experimental.macros
+
+import chisel3.internal._
+import chisel3.internal.Builder.pushCommand
+import chisel3.internal.Builder.dynamicContext
+import chisel3.internal.firrtl._
+import chisel3.internal.firrtl.{Command, Component, DefInstance, DefInvalid, ModuleIO}
+import chisel3.internal.sourceinfo.{SourceInfo, InstTransform, UnlocatableSourceInfo}
+
+object Module {
+  /** A wrapper method that all Module instantiations must be wrapped in
+    * (necessary to help Chisel track internal state).
+    *
+    * @param m the Module being created
+    *
+    * @return the input module `m` with Chisel metadata properly set
+    */
+  def apply[T <: Module](bc: => T): T = macro InstTransform.apply[T]
+
+  def do_apply[T <: Module](bc: => T)(implicit sourceInfo: SourceInfo): T = {
+    // Don't generate source info referencing parents inside a module, sincce this interferes with
+    // module de-duplication in FIRRTL emission.
+    val childSourceInfo = UnlocatableSourceInfo
+
+    val parent: Option[Module] = Builder.currentModule
+    val m = bc.setRefs() // This will set currentModule!
+    m._commands.prepend(DefInvalid(childSourceInfo, m.io.ref)) // init module outputs
+    Builder.currentModule = parent // Back to parent!
+    val ports = m.computePorts
+    Builder.components += Component(m, m.name, ports, m._commands)
+    // Avoid referencing 'parent' in top module
+    if(!Builder.currentModule.isEmpty) {
+      pushCommand(DefInstance(sourceInfo, m, ports))
+      m.setupInParent(childSourceInfo)
+    }
+
+    m
+  }
+}
+
+/** Abstract base class for Modules, which behave much like Verilog modules.
+  * These may contain both logic and state which are written in the Module
+  * body (constructor).
+  *
+  * @note Module instantiations must be wrapped in a Module() call.
+  */
+abstract class Module(
+  override_clock: Option[Clock]=None, override_reset: Option[Bool]=None)
+extends HasId {
+  // _clock and _reset can be clock and reset in these 2ary constructors
+  // once chisel2 compatibility issues are resolved
+  def this(_clock: Clock) = this(Option(_clock), None)
+  def this(_reset: Bool)  = this(None, Option(_reset))
+  def this(_clock: Clock, _reset: Bool) = this(Option(_clock), Option(_reset))
+
+  // This function binds the iodef as a port in the hardware graph
+  private[chisel3] def Port[T<:Data](iodef: T): iodef.type = {
+    // Bind each element of the iodef to being a Port
+    Binding.bind(iodef, PortBinder(this), "Error: iodef")
+    iodef
+  }
+
+  private[this] var ioDefined: Boolean = false
+
+  /**
+   * 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).
+   *
+   * TODO(twigg): Specifically walk the Data definition to call out which nodes
+   * are problematic.
+   */
+  def IO[T<:Data](iodef: T): iodef.type = {
+    require(!ioDefined, "Another IO definition for this module was already declared!")
+    ioDefined = true
+
+    Port(iodef)
+  }
+
+  private[core] val _namespace = Builder.globalNamespace.child
+  private[chisel3] val _commands = ArrayBuffer[Command]()
+  private[code] val _ids = ArrayBuffer[HasId]()
+  Builder.currentModule = Some(this)
+
+  /** Name of the instance. */
+  val name = Builder.globalNamespace.name(getClass.getName.split('.').last)
+
+  /** IO for this Module. At the Scala level (pre-FIRRTL transformations),
+    * connections in and out of a Module may only go through `io` elements.
+    */
+  def io: Bundle
+  val clock = Port(Input(Clock()))
+  val reset = Port(Input(Bool()))
+
+  private[chisel3] def addId(d: HasId) { _ids += d }
+
+  private[core] def ports: Seq[(String,Data)] = Vector(
+    ("clk", clock), ("reset", reset), ("io", io)
+  )
+
+  private[core] def computePorts: Seq[firrtl.Port] =
+    for((name, port) <- ports) yield {
+      // Port definitions need to know input or output at top-level.
+      // By FIRRTL semantics, 'flipped' becomes an Input
+      val direction = if(Data.isFlipped(port)) Direction.Input else Direction.Output
+      firrtl.Port(port, direction)
+    }
+
+  private[core] def setupInParent(implicit sourceInfo: SourceInfo): this.type = {
+    _parent match {
+      case Some(p) => {
+        pushCommand(DefInvalid(sourceInfo, io.ref)) // init instance inputs
+        clock := override_clock.getOrElse(p.clock)
+        reset := override_reset.getOrElse(p.reset)
+        this
+      }
+      case None => this
+    }
+  }
+
+  private[core] def setRefs(): this.type = {
+    for ((name, port) <- ports) {
+      port.setRef(ModuleIO(this, _namespace.name(name)))
+    }
+
+    // Suggest names to nodes using runtime reflection
+    val valNames = HashSet[String](getClass.getDeclaredFields.map(_.getName):_*)
+    def isPublicVal(m: java.lang.reflect.Method) =
+      m.getParameterTypes.isEmpty && valNames.contains(m.getName)
+    val methods = getClass.getMethods.sortWith(_.getName > _.getName)
+    for (m <- methods; if isPublicVal(m)) m.invoke(this) match {
+      case (id: HasId) => id.suggestName(m.getName)
+      case _ =>
+    }
+
+    // For Module instances we haven't named, suggest the name of the Module
+    _ids foreach {
+      case m: Module => m.suggestName(m.name)
+      case _ =>
+    }
+
+    // All suggestions are in, force names to every node.
+    _ids.foreach(_.forceName(default="T", _namespace))
+    _ids.foreach(_._onModuleClose)
+    this
+  }
+}