Address review feedback

  - Rename CodeRepository to ByteCodeRepository
  - Scaladoc on OptimizerReporting
  - Scaladoc on ByteCodeRepository

Author: lrytz

src/compiler/scala/tools/nsc/backend/jvm/BTypes.scala

@@ -9,7 +9,7 @@ package backend.jvm
 import scala.tools.asm
 import asm.Opcodes
 import scala.tools.asm.tree.{InnerClassNode, ClassNode}
-import opt.CodeRepository
+import opt.ByteCodeRepository
 import scala.collection.convert.decorateAsScala._
 
 /**
@@ -32,7 +32,10 @@ abstract class BTypes {
   /**
    * Tools for parsing classfiles, used by the inliner.
    */
-  val codeRepository: CodeRepository
+  val byteCodeRepository: ByteCodeRepository
+
+  // Allows to define per-run caches here and in the CallGraph component, which don't have a global
+  def recordPerRunCache[T <: collection.generic.Clearable](cache: T): T
 
   /**
    * A map from internal names to ClassBTypes. Every ClassBType is added to this map on its
@@ -45,13 +48,13 @@ abstract class BTypes {
    * Concurrent because stack map frames are computed when in the class writer, which might run
    * on multiple classes concurrently.
    */
-  val classBTypeFromInternalName: collection.concurrent.Map[InternalName, ClassBType]
+  val classBTypeFromInternalName: collection.concurrent.Map[InternalName, ClassBType] = recordPerRunCache(collection.concurrent.TrieMap.empty[InternalName, ClassBType])
 
   /**
    * Parse the classfile for `internalName` and construct the [[ClassBType]].
    */
   def classBTypeFromParsedClassfile(internalName: InternalName): ClassBType = {
-    classBTypeFromClassNode(codeRepository.classNode(internalName))
+    classBTypeFromClassNode(byteCodeRepository.classNode(internalName))
   }
 
   /**
@@ -90,7 +93,7 @@ abstract class BTypes {
      */
     def nestedInCurrentClass(innerClassNode: InnerClassNode): Boolean = {
       (innerClassNode.outerName != null && innerClassNode.outerName == classNode.name) ||
-      (innerClassNode.outerName == null && codeRepository.classNode(innerClassNode.name).outerClass == classNode.name)
+      (innerClassNode.outerName == null && byteCodeRepository.classNode(innerClassNode.name).outerClass == classNode.name)
     }
 
     val nestedClasses: List[ClassBType] = classNode.innerClasses.asScala.collect({

src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala

@@ -7,7 +7,9 @@ package scala.tools.nsc
 package backend.jvm
 
 import scala.tools.asm
-import opt.CodeRepository
+import opt.ByteCodeRepository
+import scala.tools.asm.tree.ClassNode
+import scala.tools.nsc.backend.jvm.opt.ByteCodeRepository.Source
 import BTypes.InternalName
 
 /**
@@ -34,15 +36,13 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes {
   val coreBTypes = new CoreBTypesProxy[this.type](this)
   import coreBTypes._
 
-  val codeRepository = new CodeRepository(global.classPath)
+  val byteCodeRepository = new ByteCodeRepository(global.classPath, recordPerRunCache(collection.concurrent.TrieMap.empty[InternalName, (ClassNode, Source)]))
 
   final def initializeCoreBTypes(): Unit = {
     coreBTypes.setBTypes(new CoreBTypes[this.type](this))
   }
 
-  val classBTypeFromInternalName = {
-    global.perRunCaches.recordCache(collection.concurrent.TrieMap.empty[InternalName, ClassBType])
-  }
+  def recordPerRunCache[T <: collection.generic.Clearable](cache: T): T = perRunCaches.recordCache(cache)
 
   // helpers that need access to global.
   // TODO @lry create a separate component, they don't belong to BTypesFromSymbols

src/compiler/scala/tools/nsc/backend/jvm/opt/CodeRepository.scala renamed to src/compiler/scala/tools/nsc/backend/jvm/opt/ByteCodeRepository.scala

@@ -13,22 +13,32 @@ import scala.collection.convert.decorateAsScala._
 import scala.tools.nsc.io.AbstractFile
 import scala.tools.nsc.util.ClassFileLookup
 import OptimizerReporting._
+import ByteCodeRepository._
+import BTypes.InternalName
 
-class CodeRepository(val classPath: ClassFileLookup[AbstractFile]) {
-  import BTypes.InternalName
-
+/**
+ * The ByteCodeRepository provides utilities to read the bytecode of classfiles from the compilation
+ * classpath. Parsed classes are cached in the `classes` map.
+ *
+ * @param classPath The compiler classpath where classfiles are searched and read from.
+ * @param classes   Cache for parsed ClassNodes. Also stores the source of the bytecode:
+ *                  [[Classfile]] if read from `classPath`, [[CompilationUnit]] if the bytecode
+ *                  corresponds to a class being compiled.
+ */
+class ByteCodeRepository(val classPath: ClassFileLookup[AbstractFile], val classes: collection.concurrent.Map[InternalName, (ClassNode, Source)]) {
   /**
-   * Cache for parsed ClassNodes.
+   * The class node and source for an internal name. If the class node is not yet available, it is
+   * parsed from the classfile on the compile classpath.
    */
-  val classes: collection.concurrent.Map[InternalName, ClassNode] = collection.concurrent.TrieMap.empty[InternalName, ClassNode]
+  def classNodeAndSource(internalName: InternalName): (ClassNode, Source) = {
+    classes.getOrElseUpdate(internalName, (parseClass(internalName), Classfile))
+  }
 
   /**
    * The class node for an internal name. If the class node is not yet available, it is parsed from
    * the classfile on the compile classpath.
    */
-  def classNode(internalName: InternalName): ClassNode = {
-    classes.getOrElseUpdate(internalName, parseClass(internalName))
-  }
+  def classNode(internalName: InternalName) = classNodeAndSource(internalName)._1
 
   /**
    * The field node for a field matching `name` and `descriptor`, accessed in class `classInternalName`.
@@ -74,7 +84,6 @@ class CodeRepository(val classPath: ClassFileLookup[AbstractFile]) {
       //   http://docs.oracle.com/javase/specs/jvms/se7/html/jvms-4.html#jvms-4.7.11
       //   https://jcp.org/aboutJava/communityprocess/final/jsr045/index.html
       removeLineNumberNodes(classNode)
-      classes(internalName) = classNode
       classNode
     } getOrElse {
       inlineFailure(s"Class file for class $fullName not found.")
@@ -91,3 +100,13 @@ class CodeRepository(val classPath: ClassFileLookup[AbstractFile]) {
     }
   }
 }
+
+object ByteCodeRepository {
+  /**
+   * The source of a ClassNode in the ByteCodeRepository. Can be either [[CompilationUnit]] if the
+   * class is being compiled or [[Classfile]] if the class was parsed from the compilation classpath.
+   */
+  sealed trait Source
+  object CompilationUnit extends Source
+  object Classfile extends Source
+}

src/compiler/scala/tools/nsc/backend/jvm/opt/OptimizerReporting.scala

@@ -9,6 +9,9 @@ package backend.jvm
 import scala.tools.asm
 import asm.tree._
 
+/**
+ * Reporting utilities used in the optimizer.
+ */
 object OptimizerReporting {
   def methodSignature(className: String, methodName: String, methodDescriptor: String): String = {
     className + "::" + methodName + methodDescriptor