ir: store FileInfo string in escaped format (#1690)

This should speed up the common case
as the compiler never operates on the
unescaped string.
The new escape function also fixes a bug
where ']' was not escaped even though it
is the delimiting character for FileInfo.
In order to maintain backwards
compatibility for the ProtoBuf format,
this patch adds escape/unescape calls
when going from/to protobuf format.
For better performance we should consider
changing the protobuf format.

1 files changed, 5 insertions, 5 deletions

diff --git a/src/main/scala/firrtl/Visitor.scala b/src/main/scala/firrtl/Visitor.scala
index 76b5c2cf..8bdab21b 100644
--- a/src/main/scala/firrtl/Visitor.scala
+++ b/src/main/scala/firrtl/Visitor.scala
@@ -69,15 +69,15 @@ class Visitor(infoMode: InfoMode) extends AbstractParseTreeVisitor[FirrtlNode] w
     infoMode match {
       case UseInfo =>
         if (useInfo.length == 0) NoInfo
-        else ir.FileInfo(ir.StringLit.unescape(useInfo))
+        else ir.FileInfo.fromEscaped(useInfo)
       case AppendInfo(filename) if (useInfo.length == 0) =>
-        ir.FileInfo(ir.StringLit.unescape(genInfo(filename)))
+        ir.FileInfo.fromEscaped(genInfo(filename))
       case AppendInfo(filename) =>
-        val useFileInfo = ir.FileInfo(ir.StringLit.unescape(useInfo))
-        val newFileInfo = ir.FileInfo(ir.StringLit.unescape(genInfo(filename)))
+        val useFileInfo = ir.FileInfo.fromEscaped(useInfo)
+        val newFileInfo = ir.FileInfo.fromEscaped(genInfo(filename))
         ir.MultiInfo(useFileInfo, newFileInfo)
       case GenInfo(filename) =>
-        ir.FileInfo(ir.StringLit.unescape(genInfo(filename)))
+        ir.FileInfo.fromEscaped(genInfo(filename))
       case IgnoreInfo => NoInfo
     }
   }