Add micro benchmarks

Author: mbovel

bench-micro/src/main/scala/dotty/tools/benchmarks/IsStable.scala

@@ -0,0 +1,43 @@
+package dotty.tools.benchmarks
+
+import org.openjdk.jmh.annotations.*
+import dotty.tools.dotc.{Driver, Run, Compiler}
+import dotty.tools.dotc.core.{Mode}
+import dotty.tools.dotc.core.Contexts.{ContextBase, Context, ctx}
+import dotty.tools.dotc.ast.tpd
+import dotty.tools.dotc.ast.tpd.*
+import dotty.tools.dotc.core.Types.{TermRef, Type}
+import dotty.tools.dotc.core.Types.NoPrefix
+import dotty.tools.dotc.core.Flags
+
+@State(Scope.Thread)
+class IsStable:
+  var pkg: tpd.Tree = null
+  var context: Context = null
+  var tp: Type = null
+
+  class GetTreeDriver extends Driver:
+    override def finish(compiler: Compiler, run: Run)(using Context): Unit =
+      pkg = run.units(0).tpdTree
+      context = ctx
+      super.finish(compiler, run)
+
+  @Param(Array("int", "deepSumUnstable", "deepSumStable"))
+  var valName: String = "int"
+
+  @Setup(Level.Iteration)
+  def setup() =
+    val args = Array(
+      "-classpath", System.getProperty("BENCH_CLASS_PATH"),
+      "-Ystop-after:typer",
+      "tests/isStable.scala")
+    GetTreeDriver().process(args)
+    given Context = context.withModeBits(Mode.Printing)
+    tp = pkg.symbol.requiredClass("Test").requiredValueRef(valName).underlying
+    ()
+
+  @Benchmark
+  def isStableBenchmark() =
+    given Context = context.withModeBits(Mode.Printing)
+    tp.isStable
+    ()

bench-micro/tests/isStable.scala

@@ -0,0 +1,10 @@
+import compiletime.ops.int.+
+
+class Test:
+    val int: Int = 5
+    val deepSumStable:
+        ((int.type + int.type) + (int.type + int.type)) + ((int.type + int.type) + (int.type + int.type)) +
+        ((int.type + int.type) + (int.type + int.type)) + ((int.type + int.type) + (int.type + int.type)) = ???
+    val deepSumUnstable:
+        ((Int + Int) + (Int + Int)) + ((Int + Int) + (Int + Int)) +
+        ((Int + Int) + (Int + Int)) + ((Int + Int) + (Int + Int)) = ???

build.sbt

@@ -13,6 +13,7 @@ val `scala3-tasty-inspector` = Build.`scala3-tasty-inspector`
 val `scala3-language-server` = Build.`scala3-language-server`
 val `scala3-bench` = Build.`scala3-bench`
 val `scala3-bench-bootstrapped` = Build.`scala3-bench-bootstrapped`
+val `scala3-bench-micro` = Build.`scala3-bench-micro`
 val `stdlib-bootstrapped` = Build.`stdlib-bootstrapped`
 val `stdlib-bootstrapped-tasty-tests` = Build.`stdlib-bootstrapped-tasty-tests`
 val `tasty-core` = Build.`tasty-core`

project/Build.scala

@@ -1247,6 +1247,11 @@ object Build {
   lazy val `scala3-bench-bootstrapped` = project.in(file("bench")).asDottyBench(Bootstrapped)
   lazy val `scala3-bench-run` = project.in(file("bench-run")).asDottyBench(Bootstrapped)
 
+
+  lazy val `scala3-bench-micro` = project.in(file("bench-micro"))
+    .asDottyBench(NonBootstrapped)
+    .settings(Jmh / run / mainClass := Some("org.openjdk.jmh.Main"))
+
   val testcasesOutputDir = taskKey[Seq[String]]("Root directory where tests classses are generated")
   val testcasesSourceRoot = taskKey[String]("Root directory where tests sources are generated")
   val testDocumentationRoot = taskKey[String]("Root directory where tests documentation are stored")