Avoid data copies

Author: SolalPirelli

compiler/src/dotty/tools/backend/jvm/CodeGen.scala

@@ -19,11 +19,11 @@ import scala.tools.asm.tree.*
 import tpd.*
 import dotty.tools.io.AbstractFile
 import dotty.tools.dotc.ast.Positioned
-import dotty.tools.dotc.util.NoSourcePosition
+import dotty.tools.dotc.util.{NoSourcePosition, SourceFile}
 import SymbolUtils.given
 import dotty.tools.backend.ScalaPrimitives
 import dotty.tools.dotc.interfaces.CompilerCallback
-import opt.{OptimizerUtils, CallGraph}
+import opt.{CallGraph, OptimizerUtils}
 
 class CodeGen(val primitives: ScalaPrimitives,
               val callGraph: Option[CallGraph], val bTypeLoader: BTypeLoader, val knownBTypes: KnownBTypes,
@@ -44,7 +44,6 @@ class CodeGen(val primitives: ScalaPrimitives,
     def genClassDef(cd: TypeDef): Unit =
       try
         val sym = cd.symbol
-        val sourceFile = ctx.compilationUnit.source.file
         val mainClassNode = genClass(cd)
         val mirrorClassNode =
           if !sym.isTopLevelModuleClass then null
@@ -113,7 +112,7 @@ class CodeGen(val primitives: ScalaPrimitives,
     clsFile => {
       val className = cls.name.replace('/', '.')
       ctx.compilerCallback match
-        case cb: CompilerCallback => cb.onClassGenerated(sourceFile, clsFile, className)
+        case cb: CompilerCallback => cb.onClassGenerated(SourceFile.toInterface(sourceFile), clsFile, className)
         case null => ()
 
       ctx.withIncCallback: cb =>

compiler/src/dotty/tools/backend/jvm/GenBCode.scala

@@ -9,6 +9,7 @@ import Contexts.*
 import dotty.tools.backend.ScalaPrimitives
 import dotty.tools.backend.jvm.opt.{BCodeRepository, BTypesFromClassfile, CallGraph, OptimizerKnownBTypes, OptimizerUtils}
 import dotty.tools.dotc.core.Decorators.em
+import dotty.tools.dotc.util.SourceFile
 import dotty.tools.io.*
 
 import scala.collection.mutable
@@ -137,7 +138,7 @@ class GenBCode extends Phase { self =>
   protected def run(using Context): Unit =
     codeGen.genUnit()
     ctx.compilerCallback match
-      case cb: CompilerCallback => cb.onSourceCompiled(ctx.source)
+      case cb: CompilerCallback => cb.onSourceCompiled(SourceFile.toInterface(ctx.source))
       case null => ()
 
   override def runOn(units: List[CompilationUnit])(using ctx:Context): List[CompilationUnit] = {

compiler/src/dotty/tools/backend/jvm/PostProcessor.scala

@@ -90,7 +90,7 @@ class PostProcessor(bTypeLoader: BTypeLoader, bTypes: KnownBTypes)(using Context
           if (name < dupName) ((clsPos, dupPos), (name, dupName))
           else ((dupPos, clsPos), (dupName, name))
         val locationAddendum =
-          if pos1.source.path == pos2.source.path then ""
+          if pos1.source.file.path == pos2.source.file.path then ""
           else s" (defined in ${pos2.source.file.name})"
         def nicify(name: String): String = name.replace('/', '.')
         if name1 == name2 then

compiler/src/dotty/tools/backend/jvm/analysis/AliasingAnalyzer.scala

@@ -512,9 +512,7 @@ object AliasSet {
     else {
       var newLength = set.length
       while (index >= newLength) newLength *= 2
-      val newSet = new Array[Long](newLength)
-      Array.copy(set, 0, newSet, 0, set.length)
-      newSet
+      Array.copyOf(set, newLength)
     }
   }
 

compiler/src/dotty/tools/backend/jvm/opt/LocalOpt.scala

@@ -693,9 +693,7 @@ object LocalOptImpls {
     var top = -1
     def enq(i: Int): Unit = {
       if (top == queue.length - 1) {
-        val nq = new Array[Int](queue.length * 2)
-        Array.copy(queue, 0, nq, 0, queue.length)
-        queue = nq
+        queue = Array.copyOf(queue, queue.length * 2)
       }
       top += 1
       queue(top) = i

compiler/src/dotty/tools/backend/jvm/opt/MethodMax.scala

@@ -51,9 +51,7 @@ object MethodMax {
 
       def enq(i: Int): Unit = {
         if (top == queue.length - 1) {
-          val nq = new Array[Int](queue.length * 2)
-          Array.copy(queue, 0, nq, 0, queue.length)
-          queue = nq
+          queue = Array.copyOf(queue, queue.length * 2)
         }
         top += 1
         queue(top) = i

compiler/src/dotty/tools/dotc/CompilationUnit.scala

@@ -6,18 +6,21 @@ import Contexts.*
 import SymDenotations.ClassDenotation
 import Symbols.*
 import Comments.Comment
-import util.{FreshNameCreator, SourceFile, NoSource}
+import util.{FreshNameCreator, NoSource, SourceFile}
 import util.Spans.Span
 import ast.{tpd, untpd}
 import tpd.{Tree, TreeTraverser}
-import ast.Trees.{Import, Ident}
+import ast.Trees.{Ident, Import}
 import typer.Nullables
 import core.Decorators.*
-import config.{SourceVersion, Feature}
+import config.{Feature, SourceVersion}
+
 import scala.annotation.internal.sharable
 import scala.util.control.NoStackTrace
 import transform.MacroAnnotations.isMacroAnnotation
 
+import scala.io.Codec
+
 class CompilationUnit protected (val source: SourceFile, val info: CompilationUnitInfo | Null) {
 
   override def toString: String = source.toString
@@ -146,7 +149,7 @@ object CompilationUnit {
   def apply(clsd: ClassDenotation, unpickled: Tree, forceTrees: Boolean)(using Context): CompilationUnit =
     val compilationUnitInfo = clsd.symbol.compilationUnitInfo.nn
     val file = compilationUnitInfo.associatedFile
-    apply(SourceFile(file, Array.emptyCharArray), unpickled, forceTrees, compilationUnitInfo)
+    apply(SourceFile(file, Codec(ctx.settings.encoding.value)), unpickled, forceTrees, compilationUnitInfo)
 
   /** Make a compilation unit, given picked bytes and unpickled tree */
   def apply(source: SourceFile, unpickled: Tree, forceTrees: Boolean, info: CompilationUnitInfo)(using Context): CompilationUnit = {

compiler/src/dotty/tools/dotc/ast/Trees.scala

@@ -899,7 +899,7 @@ object Trees {
     override def isTerm: Boolean = name.isTermName
 
     override def nameSpan(using Context): Span =
-      if span.exists then Span(span.start, span.start + name.toString.length) else span
+      if span.exists then Span(span.start, span.start + name.length) else span
   }
 
   /** tree_1 | ... | tree_n */

compiler/src/dotty/tools/dotc/ast/tpd.scala

@@ -1393,7 +1393,7 @@ object tpd extends Trees.Instance[Type] with TypedTreeInfo {
 
   // convert a numeric with a toXXX method
   def primitiveConversion(tree: Tree, numericCls: Symbol)(using Context): Tree =
-    val mname      = "to".concat(numericCls.name)
+    val mname      = termName("to" + numericCls.name)
     val conversion = tree.tpe.member(mname)
     if conversion.symbol.exists then
       tree.select(conversion.symbol.termRef).ensureApplied

compiler/src/dotty/tools/dotc/core/Contexts.scala

@@ -784,7 +784,7 @@ object Contexts {
     @tailrec
     def originalCompilationUnit: CompilationUnit =
       val cu = ctx.compilationUnit
-      if cu.source.name == SyntaxHighlighting.VirtualSourceName then ctx.outer.originalCompilationUnit
+      if cu.source.file.name == SyntaxHighlighting.VirtualSourceName then ctx.outer.originalCompilationUnit
       else cu
 
   extension (c: Context)
@@ -1093,15 +1093,8 @@ object Contexts {
     private[Contexts] val comparers = new mutable.ArrayBuffer[TypeComparer]
     private[Contexts] var comparersInUse: Int = 0
 
-    private var charArray = new Array[Char](256)
-
     private[dotc] var wConfCache: (List[String], WConf) = uninitialized
 
-    def sharedCharArray(len: Int): Array[Char] =
-      while len > charArray.length do
-        charArray = new Array[Char](charArray.length * 2)
-      charArray
-
     def reset(): Unit =
       uniques.clear()
       uniqueAppliedTypes.clear()