Fix signed types (#422)

* type conversions between sint/fixed and uint added at memory interfaces for replseqmem

* turns out asFixed requires bp as constant in PrimOps (really should be documented)

* fixed legalizeconnects to handle FixedPt

* added tests for replseqmem failure with signed types

1 files changed, 1 insertions, 1 deletions

diff --git a/src/main/scala/firrtl/passes/Passes.scala b/src/main/scala/firrtl/passes/Passes.scala
index 87458a2b..0e91c642 100644
--- a/src/main/scala/firrtl/passes/Passes.scala
+++ b/src/main/scala/firrtl/passes/Passes.scala
@@ -210,7 +210,7 @@ object Legalize extends Pass {
       val expr = t match {
         case UIntType(_) => bits
         case SIntType(_) => DoPrim(AsSInt, Seq(bits), Seq(), SIntType(IntWidth(w)))
-        //case FixedType(width, point) => FixedType(width, point)
+        case FixedType(_, IntWidth(p)) => DoPrim(AsFixedPoint, Seq(bits), Seq(p), t)
       }
       Connect(c.info, c.loc, expr)
     }