Low-level optimization.

Eliminated a bunch of unnecessary array expense.

2 files changed, 6 insertions, 3 deletions

diff --git a/src/scalap/scala/tools/scalap/ByteArrayReader.scala b/src/scalap/scala/tools/scalap/ByteArrayReader.scala
index 73220d1048..466ec53c79 100644
--- a/src/scalap/scala/tools/scalap/ByteArrayReader.scala
+++ b/src/scalap/scala/tools/scalap/ByteArrayReader.scala
@@ -72,7 +72,7 @@ class ByteArrayReader(content: Array[Byte]) {
   /** read an UTF8 encoded string
    */
   def nextUTF8(len: Int): String = {
-    val cs = scala.io.Codec.fromUTF8(buf.slice(bp, bp + len))
+    val cs = scala.io.Codec.fromUTF8(buf, bp, len)
     bp += len
     new String(cs)
   }
diff --git a/src/scalap/scala/tools/scalap/scalax/rules/scalasig/ClassFileParser.scala b/src/scalap/scala/tools/scalap/scalax/rules/scalasig/ClassFileParser.scala
index d53d8e1fc1..84f28af7ce 100644
--- a/src/scalap/scala/tools/scalap/scalax/rules/scalasig/ClassFileParser.scala
+++ b/src/scalap/scala/tools/scalap/scalax/rules/scalasig/ClassFileParser.scala
@@ -65,8 +65,11 @@ class ByteCode(val bytes : Array[Byte], val pos : Int, val length : Int) {
    * stores and array of bytes for the decompiler
    */
   def fromUTF8StringAndBytes = {
-    val chunk: Array[Byte] = bytes drop pos take length
-    StringBytesPair(io.Codec.fromUTF8(chunk).mkString, chunk)
+    val chunk: Array[Byte] = new Array[Byte](length)
+    System.arraycopy(bytes, pos, chunk, 0, length)
+    val str = new String(io.Codec.fromUTF8(bytes, pos, length))
+    
+    StringBytesPair(str, chunk)
   }
 
   def byte(i : Int) = bytes(pos) & 0xFF