1 files changed, 20 insertions, 0 deletions
diff --git a/src/main/scala/firrtl/options/Phase.scala b/src/main/scala/firrtl/options/Phase.scala
new file mode 100644
index 00000000..22715bc2
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+++ b/src/main/scala/firrtl/options/Phase.scala
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+// See LICENSE for license details.
+
+package firrtl.options
+
+import firrtl.AnnotationSeq
+
+/** A transformation of an [[AnnotationSeq]]
+  *
+  * A [[Phase]] forms one block in the Chisel/FIRRTL Hardware Compiler Framework (HCF). Note that a [[Phase]] may
+  * consist of multiple phases internally.
+  */
+abstract class Phase {
+
+  /** A transformation of an [[AnnotationSeq]]
+    * @param annotations some annotations
+    * @return transformed annotations
+    */
+  def transform(annotations: AnnotationSeq): AnnotationSeq
+
+}