Merge pull request #1123 from freechipsproject/dependency-api-2

- Use Dependency API for transform scheduling
- Add tests that old order/behavior is preserved

Or: "Now you're thinking with dependencies."

1 files changed, 13 insertions, 0 deletions

diff --git a/src/main/scala/firrtl/passes/RemoveValidIf.scala b/src/main/scala/firrtl/passes/RemoveValidIf.scala
index 42eae7e5..3b5499ac 100644
--- a/src/main/scala/firrtl/passes/RemoveValidIf.scala
+++ b/src/main/scala/firrtl/passes/RemoveValidIf.scala
@@ -2,9 +2,11 @@
 
 package firrtl
 package passes
+
 import firrtl.Mappers._
 import firrtl.ir._
 import Utils.throwInternalError
+import firrtl.options.Dependency
 
 /** Remove [[firrtl.ir.ValidIf ValidIf]] and replace [[firrtl.ir.IsInvalid IsInvalid]] with a connection to zero */
 object RemoveValidIf extends Pass {
@@ -27,6 +29,17 @@ object RemoveValidIf extends Pass {
     case other => throwInternalError(s"Unexpected type $other")
   }
 
+  override val prerequisites = firrtl.stage.Forms.LowForm
+
+  override val dependents =
+    Seq( Dependency[SystemVerilogEmitter],
+         Dependency[VerilogEmitter] )
+
+  override def invalidates(a: Transform): Boolean = a match {
+    case Legalize | _: firrtl.transforms.ConstantPropagation => true
+    case _ => false
+  }
+
   // Recursive. Removes ValidIfs
   private def onExp(e: Expression): Expression = {
     e map onExp match {