FlattenSequence/distance(from:to:) benchmarks (swiftlang#71648).

Author: oscbyspro

benchmark/CMakeLists.txt

@@ -95,6 +95,7 @@ set(SWIFT_BENCH_MODULES
     single-source/ExistentialPerformance
     single-source/Fibonacci
     single-source/FindStringNaive
+    single-source/FlattenDistanceFromTo
     single-source/FlattenList
     single-source/FloatingPointConversion
     single-source/FloatingPointParsing

benchmark/single-source/FlattenDistanceFromTo.swift

@@ -0,0 +1,58 @@
+//===--- FlattenDistanceFromTo.swift --------------------------------------===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2024 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
+//
+//===----------------------------------------------------------------------===//
+
+import TestsUtils
+
+public let FlattenDistanceFromTo = [
+  BenchmarkInfo(
+    name: "FlattenDistanceFromTo.RandomAccess.16x16",
+    runFunction: { withRandomAccess(16, 16, $0) },
+    tags: [.validation, .api]),
+  
+  BenchmarkInfo(
+    name: "FlattenDistanceFromTo.RandomAccess.16x32",
+    runFunction: { withRandomAccess(16, 32, $0) },
+    tags: [.validation, .api]),
+  
+  BenchmarkInfo(
+    name: "FlattenDistanceFromTo.RandomAccess.32x16",
+    runFunction: { withRandomAccess(32, 16, $0) },
+    tags: [.validation, .api]),
+  
+  BenchmarkInfo(
+    name: "FlattenDistanceFromTo.RandomAccess.32x32",
+    runFunction: { withRandomAccess(32, 32, $0) },
+    tags: [.validation, .api]),
+]
+
+@inline(never)
+public func withRandomAccess(
+  _ outer: Int,
+  _ inner: Int,
+  _ iterations: Int
+) {
+  var value = 0 as Int
+  let minor = repeatElement(00000, count: inner)
+  let major = repeatElement(minor, count: outer)
+  let flattened: FlattenSequence = major.joined()
+  
+  for _ in 0 ..< iterations {
+    for a in flattened.indices {
+      for b in flattened.indices {
+        value &+= flattened.distance(from: a, to: b)
+        value &+= flattened.distance(from: b, to: a)
+      }
+    }
+  }
+  
+  blackHole(value == 0)
+}

benchmark/utils/main.swift

@@ -89,6 +89,7 @@ import Exclusivity
 import ExistentialPerformance
 import Fibonacci
 import FindStringNaive
+import FlattenDistanceFromTo
 import FlattenList
 import FloatingPointConversion
 import FloatingPointParsing