Fix bug in VerilogMemDelays (#795)

* Change VerilogMemDelays to put new Statements at end of Module

Fixes #547

This is instead of putting them right after the modified DefMemory which could
result in use before declaration errors for things that feed into the new
logic.

* Adds tests that show VerilogMemDelays crashing. (#792)

1 files changed, 52 insertions, 0 deletions

diff --git a/src/test/scala/firrtlTests/VerilogMemDelaySpec.scala b/src/test/scala/firrtlTests/VerilogMemDelaySpec.scala
new file mode 100644
index 00000000..405f5ab5
--- /dev/null
+++ b/src/test/scala/firrtlTests/VerilogMemDelaySpec.scala
@@ -0,0 +1,52 @@
+// See LICENSE for license details.
+
+package firrtlTests
+
+import firrtl._
+import firrtl.passes.memlib.VerilogMemDelays
+import firrtl.passes.CheckHighForm
+import org.scalatest.{FreeSpec, Matchers}
+
+class VerilogMemDelaySpec extends FreeSpec with Matchers {
+  "The following low FIRRTL should be parsed by VerilogMemDelays" in {
+    val input =
+      """
+        |circuit Test :
+        |  module Test :
+        |    input clock : Clock
+        |    input addr : UInt<5>
+        |    input mask : { a : UInt<1>, b: UInt<1> }[2]
+        |    output out : { a : UInt<8>, b : UInt<8>}[2]
+        |    mem m :
+        |      data-type => { a : UInt<8>, b : UInt<8>}[2]
+        |      depth => 32
+        |      read-latency => 0
+        |      write-latency => 1
+        |      reader => read
+        |      writer => write
+        |    m.read.clk <= clock
+        |    m.read.en <= UInt<1>(1)
+        |    m.read.addr <= addr
+        |    out <= m.read.data
+        |
+        |    m.write.clk <= clock
+        |    m.write.en <= UInt<1>(1)
+        |    m.write.mask <= mask
+        |    m.write.addr <= addr
+        |    wire w : { a : UInt<8>, b : UInt<8>}[2]
+        |    w[0].a <= UInt<4>(2)
+        |    w[0].b <= UInt<4>(3)
+        |    w[1].a <= UInt<4>(4)
+        |    w[1].b <= UInt<4>(5)
+        |    m.write.data <= w
+      """.stripMargin
+
+    val circuit = Parser.parse(input)
+    val compiler = new LowFirrtlCompiler
+
+    val result = compiler.compile(CircuitState(circuit, ChirrtlForm), Seq.empty)
+    val result2 = VerilogMemDelays.run(result.circuit)
+    CheckHighForm.run(result2)
+    //result.circuit.serialize.length > 0 should be (true)
+  }
+}