Use name table for string attributes

Author: nicolasstucki

compiler/src/dotty/tools/dotc/core/tasty/AttributePickler.scala

@@ -21,8 +21,9 @@ object AttributePickler:
     assert(attributes.stringTagValues.exists(_._1 == TastyFormat.SOURCEFILEattr))
     for (tag, value) <- attributes.stringTagValues do
       assert(TastyFormat.firstStringAttrTag <= tag && tag < TastyFormat.firstUnassignedAttrTag, "Not a string attribute tag: " + tag)
+      val utf8Ref = pickler.nameBuffer.utf8Index(value)
       buf.writeByte(tag)
-      buf.writeUtf8(value)
+      buf.writeNat(utf8Ref.index)
 
   end pickleAttributes
 

compiler/src/dotty/tools/dotc/core/tasty/AttributeUnpickler.scala

@@ -6,8 +6,9 @@ import scala.collection.immutable.BitSet
 import scala.collection.immutable.TreeMap
 
 import dotty.tools.tasty.{TastyFormat, TastyReader, TastyBuffer}
+import dotty.tools.dotc.core.tasty.TastyUnpickler.NameTable
 
-class AttributeUnpickler(reader: TastyReader):
+class AttributeUnpickler(reader: TastyReader, nameAtRef: NameTable):
   import reader._
 
   lazy val attributes: Attributes = {
@@ -19,7 +20,9 @@ class AttributeUnpickler(reader: TastyReader):
       if tag < TastyFormat.firstStringAttrTag then
         booleanTags += tag
       else if tag < TastyFormat.firstUnassignedAttrTag then
-        stringTagValue += tag -> readUtf8()
+        val utf8Ref = readNameRef()
+        val value = nameAtRef(utf8Ref).toString
+        stringTagValue += tag -> value
       else
         assert(false, "unknown attribute tag: " + tag)
 

compiler/src/dotty/tools/dotc/core/tasty/DottyUnpickler.scala

@@ -39,7 +39,7 @@ object DottyUnpickler {
 
   class AttributesSectionUnpickler extends SectionUnpickler[AttributeUnpickler](AttributesSection) {
     def unpickle(reader: TastyReader, nameAtRef: NameTable): AttributeUnpickler =
-      new AttributeUnpickler(reader)
+      new AttributeUnpickler(reader, nameAtRef)
   }
 }
 

compiler/src/dotty/tools/dotc/core/tasty/NameBuffer.scala

@@ -49,6 +49,10 @@ class NameBuffer extends TastyBuffer(10000) {
     }
   }
 
+  def utf8Index(value: String): NameRef =
+    import Decorators.toTermName
+    nameIndex(value.toTermName)
+
   private inline def withLength(inline op: Unit, lengthWidth: Int = 1): Unit = {
     val lengthAddr = currentAddr
     var i = 0

compiler/src/dotty/tools/dotc/core/tasty/TastyPrinter.scala

@@ -228,14 +228,16 @@ class TastyPrinter(bytes: Array[Byte]) {
     import dotty.tools.tasty.TastyFormat.*
     def unpickle(reader: TastyReader, tastyName: NameTable): Unit = {
       import reader.*
-      val attributes = new AttributeUnpickler(reader).attributes
       sb.append(s"\n\nAttributes (${reader.endAddr.index - reader.startAddr.index} bytes, starting from $base):\n")
-
-      for tag <- attributes.booleanTags do
-        sb.append("  ").append(attributeTagToString(tag)).append("\n")
-      for (tag, value) <- attributes.stringTagValues do
+      while !isAtEnd do
+        val tag = readByte()
         sb.append("  ").append(attributeTagToString(tag))
-          .append(" ").append(value).append("\n")
+        if tag < firstStringAttrTag then ()
+        else if tag < firstUnassignedAttrTag then
+          val utf8Ref = readNameRef()
+          val value = nameAtRef(utf8Ref).toString
+          sb.append(nameStr(s" ${utf8Ref.index} [$value]"))
+        sb.append("\n")
       sb.result
     }
   }

tasty/src/dotty/tools/tasty/TastyFormat.scala

@@ -50,6 +50,7 @@ Macro-format:
                       // If positive, this is a NameRef for the fully qualified name of a term parameter.
 
   NameRef       = Nat                    // ordinal number of name in name table, starting from 1.
+  Utf8Ref       = Nat                    // ordinal number of UTF8 in name table, starting from 1.
 ```
 
 Note: Unqualified names in the name table are strings. The context decides whether a name is
@@ -278,13 +279,13 @@ Standard Section: "Attributes" Attribute*
                   WITHPUREFUNSattr
                   JAVAattr
                   OUTLINEattr
-                  SOURCEFILEattr Utf8
+                  SOURCEFILEattr Utf8Ref
 ```
 
 Note: Attribute tags are grouped into 2 categories that determine what follows, and thus allow to compute the size of the tagged tree in a generic way.
 ```none
   Attribute Category 1 (tags 1-64)  :  tag
-  Attribute Category 2 (tags 65-128):  tag UTF8
+  Attribute Category 2 (tags 65-128):  tag Utf8Ref
 ```
 
 **************************************************************************************/