Fixes SI-6172.

All the credit for fixing magical constants in the encoding algorithm goes to @magarciaEPFL.
This time provided a test case that exercises GenASM.

1 files changed, 4 insertions, 4 deletions

diff --git a/src/compiler/scala/tools/nsc/backend/jvm/GenASM.scala b/src/compiler/scala/tools/nsc/backend/jvm/GenASM.scala
index f681de93b6..a804cc92d3 100644
--- a/src/compiler/scala/tools/nsc/backend/jvm/GenASM.scala
+++ b/src/compiler/scala/tools/nsc/backend/jvm/GenASM.scala
@@ -932,7 +932,6 @@ abstract class GenASM extends SubComponent with BytecodeWriters {
       ca
     }
 
-    // TODO this method isn't exercised during bootstrapping. Open question: is it bug free?
     private def arrEncode(sb: ScalaSigBytes): Array[String] = {
       var strs: List[String]  = Nil
       val bSeven: Array[Byte] = sb.sevenBitsMayBeZero
@@ -941,14 +940,15 @@ abstract class GenASM extends SubComponent with BytecodeWriters {
       var offset     = 0
       var encLength  = 0
       while(offset < bSeven.size) {
-        val newEncLength = encLength.toLong + (if(bSeven(offset) == 0) 2 else 1)
-        if(newEncLength > 65535) {
+        val deltaEncLength = (if(bSeven(offset) == 0) 2 else 1)
+        val newEncLength = encLength.toLong + deltaEncLength
+        if(newEncLength >= 65535) {
           val ba     = bSeven.slice(prevOffset, offset)
           strs     ::= new java.lang.String(ubytesToCharArray(ba))
           encLength  = 0
           prevOffset = offset
         } else {
-          encLength += 1
+          encLength += deltaEncLength
           offset    += 1
         }
       }