Move barstools tapeout src to tools/tapeout

tools/tapeout/src/main/scala/transforms/retime/Retime.scala

@@ -0,0 +1,48 @@
+// See LICENSE for license details.
+
+package barstools.tapeout.transforms.retime
+
+import chisel3.experimental.RunFirrtlTransform
+import firrtl.annotations._
+import firrtl.stage.Forms
+import firrtl.stage.TransformManager.TransformDependency
+import firrtl.{CircuitState, DependencyAPIMigration, Transform}
+
+case class RetimeAnnotation(target: Named) extends SingleTargetAnnotation[Named] {
+  override def duplicate(n: Named): Annotation = RetimeAnnotation(n)
+}
+
+class RetimeTransform extends Transform with DependencyAPIMigration {
+
+  override def prerequisites:          Seq[TransformDependency] = Forms.LowForm
+  override def optionalPrerequisites:  Seq[TransformDependency] = Forms.LowFormOptimized
+  override def optionalPrerequisiteOf: Seq[TransformDependency] = Forms.LowEmitters
+  override def invalidates(a: Transform): Boolean = false
+
+  override def execute(state: CircuitState): CircuitState = {
+    state.annotations.filter(_.isInstanceOf[RetimeAnnotation]) match {
+      case Nil => state
+      case seq =>
+        seq.foreach {
+          case RetimeAnnotation(ModuleName(module, CircuitName(_))) =>
+            logger.info(s"Retiming module $module")
+          case RetimeAnnotation(ComponentName(name, ModuleName(module, CircuitName(_)))) =>
+            logger.info(s"Retiming instance $module.$name")
+          case _ =>
+            throw new Exception(s"There should be RetimeAnnotations, got ${seq.mkString(" -- ")}")
+        }
+        state
+    }
+  }
+}
+
+trait RetimeLib {
+  self: chisel3.Module =>
+
+  def retime[T <: chisel3.Module](module: T): Unit = {
+    chisel3.experimental.annotate(new chisel3.experimental.ChiselAnnotation with RunFirrtlTransform {
+      def transformClass: Class[_ <: Transform] = classOf[RetimeTransform]
+      def toFirrtl:       Annotation = RetimeAnnotation(module.toNamed)
+    })
+  }
+}