Merge pull request #109 from ucb-bar/Fix-init-in-DeqIO

Fix init in deq io

1 files changed, 63 insertions, 0 deletions

diff --git a/src/test/scala/chiselTests/VectorPacketIO.scala b/src/test/scala/chiselTests/VectorPacketIO.scala
new file mode 100644
index 00000000..99ec66a6
--- /dev/null
+++ b/src/test/scala/chiselTests/VectorPacketIO.scala
@@ -0,0 +1,63 @@
+// See LICENSE for license details.
+
+package chiselTests
+
+import Chisel._
+import Chisel.testers.BasicTester
+
+/**
+  * This test used to fail when assignment statements were
+  * contained in DeqIO and EnqIO constructors.
+  * The symptom is creation of a firrtl file
+  * with missing declarations, the problem is exposed by
+  * the creation of the val outs in VectorPacketIO
+  *
+  * NOTE: The problem does not exist now because the initialization
+  * code has been removed from DeqIO and EnqIO
+  *
+  * IMPORTANT:  The canonical way to initialize a decoupled inteface is still being debated.
+  */
+class Packet extends Bundle {
+  val header = UInt(width = 1)
+}
+
+/**
+  * The problem occurs with just the ins or the outs
+  * lines also.
+  * The problem does not occur if the Vec is taken out
+  */
+class VectorPacketIO(n: Int) extends Bundle {
+  val ins  = Vec(n, new DeqIO(new Packet()))
+  val outs = Vec(n, new EnqIO(new Packet()))
+}
+
+/**
+  * a module uses the vector based IO bundle
+  * the value of n does not affect the error
+  */
+class BrokenVectorPacketModule extends Module {
+  val n  = 4
+  val io = new VectorPacketIO(n)
+
+  /* the following method of initializing the circuit may change in the future */
+  io.outs.foreach(_.init())
+}
+
+class VectorPacketIOUnitTester extends BasicTester {
+  val device_under_test = Module(new BrokenVectorPacketModule)
+
+  // This counter just makes the test end quicker
+  val c = Counter(1)
+  when(c.inc()) {
+    stop()
+  }
+}
+
+class VectorPacketIOUnitTesterSpec extends ChiselFlatSpec {
+  "a circuit using an io containing a vector of EnqIO wrapped packets" should
+    "compile and run" in {
+    assertTesterPasses {
+      new VectorPacketIOUnitTester
+    }
+  }
+}