[cxx-interop] Add support for benchmarks with C++ interop.

* Adds support for benchmarks that use C++ modules.
* Adds "CreateObjects" benchmark that creates C++ objects.

benchmark/CMakeLists.txt

@@ -188,6 +188,7 @@ set(SWIFT_BENCH_MODULES
     single-source/Walsh
     single-source/WordCount
     single-source/XorLoop
+    cxx-source/CreateObjects
 )
 
 set(SWIFT_MULTISOURCE_SWIFT_BENCHES

benchmark/Package.swift

@@ -49,6 +49,11 @@ var singleSourceLibraries: [String] = singleSourceLibraryDirs.flatMap {
   getSingleSourceLibraries(subDirectory: $0)
 }
 
+var cxxSingleSourceLibraryDirs: [String] = ["cxx-source"]
+var cxxSingleSourceLibraries: [String] = cxxSingleSourceLibraryDirs.flatMap {
+  getSingleSourceLibraries(subDirectory: $0)
+}
+
 //===---
 // Multi Source Libraries
 //
@@ -80,6 +85,7 @@ products.append(.library(name: "ObjectiveCTests", type: .static, targets: ["Obje
 products.append(.executable(name: "SwiftBench", targets: ["SwiftBench"]))
 
 products += singleSourceLibraries.map { .library(name: $0, type: .static, targets: [$0]) }
+products += cxxSingleSourceLibraries.map { .library(name: $0, type: .static, targets: [$0]) }
 products += multiSourceLibraries.map {
   return .library(name: $0.name, type: .static, targets: [$0.name])
 }
@@ -103,13 +109,18 @@ swiftBenchDeps.append(.target(name: "ObjectiveCTests"))
 #endif
 swiftBenchDeps.append(.target(name: "DriverUtils"))
 swiftBenchDeps += singleSourceLibraries.map { .target(name: $0) }
+swiftBenchDeps += cxxSingleSourceLibraries.map { .target(name: $0) }
 swiftBenchDeps += multiSourceLibraries.map { .target(name: $0.name) }
 
 targets.append(
     .target(name: "SwiftBench",
     dependencies: swiftBenchDeps,
     path: "utils",
-    sources: ["main.swift"]))
+    sources: ["main.swift"],
+    swiftSettings: [.unsafeFlags(["-Xfrontend",
+                                  "-enable-cxx-interop",
+                                  "-I",
+                                  "utils/CxxTests"])]))
 
 #if os(macOS) || os(iOS) || os(watchOS) || os(tvOS)
 targets.append(
@@ -139,6 +150,18 @@ targets += singleSourceLibraries.map { name in
       sources: ["\(name).swift"])
 }
 
+targets += cxxSingleSourceLibraries.map { name in
+  return .target(
+    name: name,
+    dependencies: singleSourceDeps,
+    path: "cxx-source",
+    sources: ["\(name).swift"],
+    swiftSettings: [.unsafeFlags(["-Xfrontend",
+                                  "-enable-cxx-interop",
+                                  "-I",
+                                  "utils/CxxTests"])])
+}
+
 targets += multiSourceLibraries.map { lib in
   return .target(
     name: lib.name,

benchmark/cmake/modules/AddSwiftBenchmarkSuite.cmake

@@ -478,6 +478,12 @@ function (swift_benchmark_compile_archopts)
       list(APPEND SWIFT_BENCH_OBJFILES "${objfile}")
       list(APPEND bench_library_swiftmodules "${swiftmodule}")
 
+      # Only set "enable-cxx-interop" for tests in the "cxx-source" directory.
+      set(cxx_options "")
+      if ("${module_name_path}" MATCHES ".*cxx-source/.*")
+        list(APPEND cxx_options "-Xfrontend" "-enable-cxx-interop" "-I" "${srcdir}/utils/CxxTests/")
+      endif()
+
       if ("${bench_flags}" MATCHES "-whole-module.*")
         set(output_option "-o" "${objfile}")
       else()
@@ -501,6 +507,7 @@ function (swift_benchmark_compile_archopts)
           "-module-name" "${module_name}"
           "-emit-module-path" "${swiftmodule}"
           "-I" "${objdir}"
+          ${cxx_options}
           ${output_option}
           "${source}")
       if (SWIFT_BENCHMARK_EMIT_SIB)
@@ -518,6 +525,7 @@ function (swift_benchmark_compile_archopts)
             ${SWIFT_BENCHMARK_EXTRA_FLAGS}
             "-module-name" "${module_name}"
             "-I" "${objdir}"
+            ${cxx_options}
             "-emit-sib"
             "-o" "${sibfile}"
             "${source}")
@@ -582,6 +590,8 @@ function (swift_benchmark_compile_archopts)
       "-whole-module-optimization"
       "-emit-module" "-module-name" "${module_name}"
       "-I" "${objdir}"
+      "-Xfrontend" "-enable-cxx-interop"
+      "-I" "${srcdir}/utils/CxxTests/"
       "-o" "${objdir}/${module_name}.o"
       "${source}")
   list(APPEND SWIFT_BENCH_OBJFILES "${objdir}/${module_name}.o")

benchmark/cxx-source/CreateObjects.swift

@@ -0,0 +1,31 @@
+//===--- CreateObjects.swift ----------------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+// This is a simple test that creates thousands of C++ objects and does nothing
+// with them.
+
+import TestsUtils
+import CxxCreateObjects
+
+public let CreateObjects = BenchmarkInfo(
+  name: "CreateObjects",
+  runFunction: run_CreateObjects,
+  tags: [.validation, .bridging])
+
+@inline(never)
+public func run_CreateObjects(_ N: Int) {
+  for i in 0...(N * 10_000) {
+    let x = Int32(i)
+    let f = CxxLoadableIntWrapper(value: x)
+    blackHole(f)
+  }
+}

benchmark/utils/CxxTests/CreateObjects.h

@@ -0,0 +1,3 @@
+struct CxxLoadableIntWrapper {
+  int value;
+};

benchmark/utils/CxxTests/module.modulemap

@@ -0,0 +1,3 @@
+module CxxCreateObjects {
+  header "CreateObjects.h"
+}

benchmark/utils/main.swift

@@ -48,6 +48,7 @@ import Chars
 import ClassArrayGetter
 import Codable
 import Combos
+import CreateObjects
 import DataBenchmarks
 import DeadArray
 import DevirtualizeProtocolComposition
@@ -235,6 +236,7 @@ registerBenchmark(Chars)
 registerBenchmark(Codable)
 registerBenchmark(Combos)
 registerBenchmark(ClassArrayGetter)
+registerBenchmark(CreateObjects)
 registerBenchmark(DataBenchmarks)
 registerBenchmark(DeadArray)
 registerBenchmark(DevirtualizeProtocolComposition)