Merge pull request #3830 from dotty-staging/enable-optimise-in-quotes

Enable optimisations in `Expr.run`

Author: nicolasstucki

compiler/src/dotty/tools/dotc/quoted/ExprCompiler.scala

@@ -3,10 +3,11 @@ package quoted
 
 import dotty.tools.backend.jvm.GenBCode
 import dotty.tools.dotc.ast.tpd
-
 import dotty.tools.dotc.core.Contexts.Context
-import dotty.tools.dotc.core.Flags.{EmptyFlags, Method}
-import dotty.tools.dotc.core.{Mode, Phases}
+import dotty.tools.dotc.core.Decorators._
+import dotty.tools.dotc.core.Flags._
+import dotty.tools.dotc.core.Mode
+import dotty.tools.dotc.core.Names.TypeName
 import dotty.tools.dotc.core.Phases.Phase
 import dotty.tools.dotc.core.Scopes.{EmptyScope, newScope}
 import dotty.tools.dotc.core.StdNames.nme
@@ -17,14 +18,14 @@ import dotty.tools.dotc.transform.ReifyQuotes
 import dotty.tools.dotc.typer.FrontEnd
 import dotty.tools.dotc.util.Positions.Position
 import dotty.tools.dotc.util.SourceFile
-import dotty.tools.io.{Path, PlainFile, VirtualDirectory}
+import dotty.tools.io.{AbstractFile, Path, PlainFile}
 
 import scala.quoted.Expr
 
 /** Compiler that takes the contents of a quoted expression `expr` and produces
  *  a class file with `class ' { def apply: Object = expr }`.
  */
-class ExprCompiler(directory: VirtualDirectory) extends Compiler {
+class ExprCompiler(directory: AbstractFile) extends Compiler {
   import tpd._
 
   /** A GenBCode phase that outputs to a virtual directory */
@@ -47,6 +48,8 @@ class ExprCompiler(directory: VirtualDirectory) extends Compiler {
     new ExprRun(this, ctx.addMode(Mode.ReadPositions))
   }
 
+  def outputClassName: TypeName = "Quoted".toTypeName
+
   /** Frontend that receives scala.quoted.Expr as input */
   class ExprFrontend(putInClass: Boolean) extends FrontEnd {
     import tpd._
@@ -72,7 +75,7 @@ class ExprCompiler(directory: VirtualDirectory) extends Compiler {
       val pos = Position(0)
       val assocFile = new PlainFile(Path("<quote>"))
 
-      val cls = ctx.newCompleteClassSymbol(defn.RootClass, nme.QUOTE.toTypeName, EmptyFlags,
+      val cls = ctx.newCompleteClassSymbol(defn.RootClass, outputClassName, EmptyFlags,
         defn.ObjectType :: Nil, newScope, coord = pos, assocFile = assocFile).entered.asClass
       cls.enter(ctx.newDefaultConstructor(cls), EmptyScope)
       val meth = ctx.newSymbol(cls, nme.apply, Method, ExprType(defn.AnyType), coord = pos).entered

compiler/src/dotty/tools/dotc/quoted/QuoteDriver.scala

@@ -1,9 +1,9 @@
 package dotty.tools.dotc.quoted
 
 import dotty.tools.dotc.Driver
-import dotty.tools.dotc.core.Contexts.{Context, FreshContext}
+import dotty.tools.dotc.core.Contexts.Context
 import dotty.tools.dotc.core.StdNames._
-import dotty.tools.io.VirtualDirectory
+import dotty.tools.io.{AbstractFile, Directory, PlainDirectory, VirtualDirectory}
 import dotty.tools.repl.AbstractFileClassLoader
 
 import scala.quoted.Expr
@@ -13,18 +13,25 @@ import java.nio.charset.StandardCharsets
 
 class QuoteDriver extends Driver {
 
-  def run[T](expr: Expr[T]): T = {
+  def run[T](expr: Expr[T], settings: Runners.RunSettings): T = {
     val ctx: Context = initCtx.fresh
-    // TODO enable optimisation?
-    // ctx.settings.optimise.update(true)(ctx)
-
-    val outDir = new VirtualDirectory("(memory)", None)
+    ctx.settings.optimise.update(settings.optimise)(ctx)
+
+    val outDir: AbstractFile = settings.outDir match {
+      case Some(out) =>
+        val dir = Directory(out)
+        dir.createDirectory()
+        new PlainDirectory(Directory(out))
+      case None =>
+        new VirtualDirectory("(memory)", None)
+    }
 
-    new ExprCompiler(outDir).newRun(ctx).compileExpr(expr)
+    val driver = new ExprCompiler(outDir)
+    driver.newRun(ctx).compileExpr(expr)
 
     val classLoader = new AbstractFileClassLoader(outDir, this.getClass.getClassLoader)
 
-    val clazz = classLoader.loadClass(nme.QUOTE.toString)
+    val clazz = classLoader.loadClass(driver.outputClassName.toString)
     val method = clazz.getMethod("apply")
     val instance = clazz.newInstance()
 

compiler/src/dotty/tools/dotc/quoted/Runners.scala

@@ -13,10 +13,7 @@ object Runners {
 
   implicit def runner[T]: Runner[T] = new Runner[T] {
 
-    def run(expr: Expr[T]): T = expr match {
-      case expr: ConstantExpr[T] => expr.value
-      case _ => new QuoteDriver().run(expr)
-    }
+    def run(expr: Expr[T]): T = Runners.run(expr, RunSettings())
 
     def show(expr: Expr[T]): String = expr match {
       case expr: ConstantExpr[T] =>
@@ -27,4 +24,16 @@ object Runners {
       case _ => new QuoteDriver().show(expr)
     }
   }
+
+  def run[T](expr: Expr[T], settings: RunSettings): T = expr match {
+    case expr: ConstantExpr[T] => expr.value
+    case _ => new QuoteDriver().run(expr, settings)
+  }
+
+  case class RunSettings(
+    /** Enable optimisation when compiling the quoted code */
+    optimise: Boolean = false,
+    /** Output directory for the copiled quote. If set to None the output will be in memory */
+    outDir: Option[String] = None
+  )
 }

tests/run-with-compiler/quote-run-with-settings.check

@@ -0,0 +1,10 @@
+{
+  val a: Int = 3
+  println("foo")
+  2.+(a)
+}
+foo
+5
+
+foo
+5

tests/run-with-compiler/quote-run-with-settings.scala

@@ -0,0 +1,29 @@
+
+import java.nio.file.{Files, Paths}
+
+import dotty.tools.dotc.quoted.Runners._
+
+import scala.quoted._
+
+object Test {
+  def main(args: Array[String]): Unit = {
+    val expr = '{
+      val a = 3
+      println("foo")
+      2 + a
+    }
+    println(expr.show)
+    println(expr.run)
+    println()
+
+    val outDir = Paths.get("../out/out-quoted-1")
+    val classFile = outDir.resolve("Quoted.class")
+
+    Files.deleteIfExists(classFile)
+
+    val settings = RunSettings(optimise = true, outDir = Some(outDir.toString))
+
+    println(run(expr, settings))
+    assert(Files.exists(classFile))
+  }
+}

tests/run-with-compiler/quote-run.check

@@ -13,4 +13,4 @@ lambda(5)
 Foo
 false
 Bar
-class '$A$1
+class Quoted$A$1