[benchmark] Add swiftpm support for the benchmark suite.

This means that we can now edit benchmarks in Xcode! Keep in mind:

1. This is not an official build. It is just so we can use Xcode to edit files
and get IDE features.
2. I had to do a little hackery to keep the build the way it is today where all
single-source files are their own modules.
3. As long as we do not change the directory structure, everything should just
update and work since I added a little code that dynamically adds the tests.

Also, to do this I had to rename multi-source/PrimsSplit/main.swift =>
Prims_main.swift. That is because the name main.swift is special in some way and
I hit linker errors. By simply changing the name from main.swift =>
Prims_main.swift, everything is good. I am going to file a separate bug for
that.

Author: gottesmm

benchmark/CMakeLists.txt

@@ -173,7 +173,7 @@ set(SWIFT_MULTISOURCE_SWIFT3_BENCHES
 
 set(PrimsSplit_sources
     multi-source/PrimsSplit/Prims.swift
-    multi-source/PrimsSplit/main.swift)
+    multi-source/PrimsSplit/Prims_main.swift)
 
 set(SWIFT_MULTISOURCE_SWIFT4_BENCHES
 )

benchmark/Package.swift

@@ -0,0 +1,88 @@
+// swift-tools-version:4.0
+
+import PackageDescription
+import Foundation
+
+// This is a stop gap hack so we can edit benchmarks in Xcode.
+let singleSourceLibraries: [String] = {
+  let f = FileManager.`default`
+  let dirURL = URL(fileURLWithPath: "single-source").absoluteURL
+  let fileURLs = try! f.contentsOfDirectory(at: dirURL,
+                                            includingPropertiesForKeys: nil)
+  return fileURLs.flatMap { (path: URL) -> String? in
+    let c = path.lastPathComponent.split(separator: ".")
+    // Too many components. Must be a gyb file.
+    if c.count > 2 {
+      return nil
+    }
+    if c[1] != "swift" {
+      return nil
+    }
+
+    // We do not support this test.
+    if c[0] == "ObjectiveCNoBridgingStubs" {
+      return nil
+    }
+
+    assert(c[0] != "PrimsSplit")
+    return String(c[0])
+  }
+}()
+
+let multiSourceLibraries: [String] = {
+  let f = FileManager.`default`
+  let dirURL = URL(fileURLWithPath: "multi-source").absoluteURL
+  let fileURLs = try! f.contentsOfDirectory(at: dirURL,
+                                            includingPropertiesForKeys: nil)
+  return fileURLs.map { (path: URL) -> String in
+    return path.lastPathComponent
+  }
+}()
+
+let p = Package(
+  name: "swiftbench",
+  products: [
+    .library(name: "TestsUtils", type: .static, targets: ["TestsUtils"]),
+    .library(name: "DriverUtils", type: .static, targets: ["DriverUtils"]),
+    .library(name: "ObjectiveCTests", type: .static, targets: ["ObjectiveCTests"]),
+    .executable(name: "SwiftBench", targets: ["SwiftBench"]),
+    .library(name: "PrimsSplit", type: .static, targets: ["PrimsSplit"])
+  ] + singleSourceLibraries.map { .library(name: $0, type: .static, targets: [$0]) }
+    + multiSourceLibraries.map { .library(name: $0, type: .static, targets: [$0]) },
+  targets: [
+    .target(name: "TestsUtils",
+      path: "utils",
+      sources: ["TestsUtils.swift"]),
+    .target(name: "DriverUtils",
+      dependencies: [.target(name: "TestsUtils")],
+      path: "utils",
+      sources: ["DriverUtils.swift", "ArgParse.swift"]),
+    .target(name: "SwiftBench",
+            dependencies: [
+              .target(name: "TestsUtils"),
+              .target(name: "ObjectiveCTests"),
+              .target(name: "DriverUtils"),
+            ] + singleSourceLibraries.map { .target(name: $0) }
+              + multiSourceLibraries.map { .target(name: $0) },
+            path: "utils",
+            sources: ["main.swift"]),
+    .target(name: "ObjectiveCTests",
+      path: "utils/ObjectiveCTests",
+      publicHeadersPath: "."),
+  ] + singleSourceLibraries.map { x in
+    return .target(name: x,
+      dependencies: [
+        .target(name: "TestsUtils"),
+        .target(name: "ObjectiveCTests"),
+      ],
+      path: "single-source",
+      sources: ["\(x).swift"])
+  } + multiSourceLibraries.map { x in
+    return .target(name: x,
+      dependencies: [
+        .target(name: "TestsUtils")
+      ],
+      path: "multi-source/\(x)")
+  },
+  swiftLanguageVersions: [4]
+)

benchmark/multi-source/PrimsSplit/main.swift renamed to benchmark/multi-source/PrimsSplit/Prims_main.swift

@@ -92,7 +92,9 @@ import NopDeinit
 import ObjectAllocation
 import ObjectiveCBridging
 import ObjectiveCBridgingStubs
+#if !SWIFT_PACKAGE
 import ObjectiveCNoBridgingStubs
+#endif
 import ObserverClosure
 import ObserverForwarderStruct
 import ObserverPartiallyAppliedMethod
@@ -252,7 +254,9 @@ registerBenchmark(NopDeinit)
 registerBenchmark(ObjectAllocation)
 registerBenchmark(ObjectiveCBridging)
 registerBenchmark(ObjectiveCBridgingStubs)
+#if !SWIFT_PACKAGE
 registerBenchmark(ObjectiveCNoBridgingStubs)
+#endif
 registerBenchmark(ObserverClosure)
 registerBenchmark(ObserverForwarderStruct)
 registerBenchmark(ObserverPartiallyAppliedMethod)