diff --git a/Benchmarks/Benchmarks/CharacterSet/BenchmarkCharacterSet.swift b/Benchmarks/Benchmarks/CharacterSet/BenchmarkCharacterSet.swift
index df07c4b4f..4c1668a1d 100644
--- a/Benchmarks/Benchmarks/CharacterSet/BenchmarkCharacterSet.swift
+++ b/Benchmarks/Benchmarks/CharacterSet/BenchmarkCharacterSet.swift
@@ -30,91 +30,91 @@ let benchmarks = {
     let string = "Hello, Let's use Character Set"
     let range = Unicode.Scalar(0x10000)!..<UnicodeScalar(0x20000)!
     let data = Data([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])
-    
+
     // MARK: Initialize CharacterSet
-    
+
     Benchmark("CharacterSet: String") { benchmark in
         for _ in benchmark.scaledIterations {
             blackHole(CharacterSet(charactersIn: string))
         }
     }
-    
+
     Benchmark("CharacterSet: Range") { benchmark in
         for _ in benchmark.scaledIterations {
             blackHole(CharacterSet(charactersIn: range))
         }
     }
-    
+
     Benchmark("CharacterSet: Predefined") { benchmark in
         for _ in benchmark.scaledIterations {
             blackHole(CharacterSet.whitespacesAndNewlines)
         }
     }
-    
+
     Benchmark("CharacterSet: Data") { benchmark in
         for _ in benchmark.scaledIterations {
             blackHole(CharacterSet(bitmapRepresentation: data))
         }
     }
-    
+
     // MARK: Get Bitmap Representation of CharacterSet
-    
+
     Benchmark("CharacterSet.GetStringBitmapRepresentation") { benchmark in
         for _ in benchmark.scaledIterations {
             blackHole(CharacterSet(charactersIn: string).bitmapRepresentation)
         }
     }
-    
+
     Benchmark("CharacterSet.GetRangeBitmapRepresentation") { benchmark in
         for _ in benchmark.scaledIterations {
             blackHole(CharacterSet(charactersIn: range).bitmapRepresentation)
         }
     }
-    
+
     Benchmark("CharacterSet.GetPredefinedBitmapRepresentation") { benchmark in
         for _ in benchmark.scaledIterations {
             blackHole(CharacterSet.whitespacesAndNewlines.bitmapRepresentation)
         }
     }
-    
+
     Benchmark("CharacterSet.GetDataBitmapRepresentation") { benchmark in
         for _ in benchmark.scaledIterations {
             blackHole(CharacterSet(bitmapRepresentation: data).bitmapRepresentation)
         }
     }
-    
+
     // MARK: Check Membership
-   
+
     Benchmark("CharacterSet: String Membership") { benchmark in
         for _ in benchmark.scaledIterations {
             let cs = CharacterSet(charactersIn: string)
             blackHole(cs.contains(UnicodeScalar("a")))
         }
     }
-    
+
     Benchmark("CharacterSet: Range Membership") { benchmark in
         for _ in benchmark.scaledIterations {
             let cs = CharacterSet(charactersIn: range)
             blackHole(cs.contains(UnicodeScalar(0x4999)!))
         }
     }
-    
+
     Benchmark("CharacterSet: Predefined Membership") { benchmark in
         for _ in benchmark.scaledIterations {
             let cs = CharacterSet.whitespacesAndNewlines
             blackHole(cs.contains(UnicodeScalar(0x0045)!))
         }
     }
-    
+
     Benchmark("CharacterSet: Data Membership") { benchmark in
         for _ in benchmark.scaledIterations {
             let cs = CharacterSet(bitmapRepresentation: data)
             blackHole(cs.contains(UnicodeScalar(0x0031)!))
         }
     }
-    
+
     // MARK: Common Usage Patterns
-    
+
     let input1 = "\n\t  hello world  \r\n"
     let input2 = "###  hello world  ###"
     let input3 = "hello world swift testing"
@@ -122,13 +122,13 @@ let benchmarks = {
     let input5 = "line1\nline2\rline3\r\nline4"
     let validAlphanumericsInput = "Test123"
     let invalidAlphanumericsInput = "Test@123"
-    
+
     Benchmark("CharacterSet: Trim Whitespaces and Newlines") { benchmark in
         for _ in benchmark.scaledIterations {
             blackHole(input1.trimmingCharacters(in: .whitespacesAndNewlines))
         }
     }
-    
+
     Benchmark("CharacterSet: Trim Custom Characters") { benchmark in
         for _ in benchmark.scaledIterations {
             var customSet = CharacterSet.whitespaces
@@ -136,30 +136,252 @@ let benchmarks = {
             blackHole(input2.trimmingCharacters(in: customSet))
         }
     }
-    
+
     Benchmark("CharacterSet: Split String by Whitespaces") { benchmark in
         for _ in benchmark.scaledIterations {
             blackHole(input3.components(separatedBy: .whitespaces))
         }
     }
-    
+
     Benchmark("CharacterSet: Split String by Inverted Decimal Digits") { benchmark in
         for _ in benchmark.scaledIterations {
             blackHole(input4.components(separatedBy: CharacterSet.decimalDigits.inverted))
         }
     }
-    
+
     Benchmark("CharacterSet: Split String by Newlines") { benchmark in
         for _ in benchmark.scaledIterations {
             blackHole(input5.components(separatedBy: .newlines).filter { !$0.isEmpty })
         }
     }
-    
+
     Benchmark("CharacterSet: Validate Alphanumerics Input") { benchmark in
         for _ in benchmark.scaledIterations {
             blackHole(CharacterSet.alphanumerics.isSuperset(of: CharacterSet(charactersIn: validAlphanumericsInput)))
             blackHole(!CharacterSet.alphanumerics.isSuperset(of: CharacterSet(charactersIn: invalidAlphanumericsInput)))
         }
     }
+    
+    // MARK: rdar://173078708 Hash & Equality & Bitmap Representation
+    Benchmark("CharacterSet: Hash Predefined CharacterSet") { benchmark in
+        for _ in benchmark.scaledIterations {
+            let cs = CharacterSet.whitespacesAndNewlines
+            var hasher = Hasher()
+            cs.hash(into: &hasher)
+            blackHole(hasher.finalize())
+        }
+    }
+    
+    Benchmark("CharacterSet Hash BMP-Only CharacterSet") { benchmark in
+        for _ in benchmark.scaledIterations {
+            let cs: CharacterSet = {
+                var cs = CharacterSet(charactersIn: "a"..."f")
+                cs.insert(charactersIn: "A"..."F")
+                cs.insert(charactersIn: "0"..."9")
+                return cs
+            }()
+            var hasher = Hasher()
+            cs.hash(into: &hasher)
+            blackHole(hasher.finalize())
+        }
+    }
+    
+    Benchmark("CharacterSet: Hash Multi-Plane CharacterSet") { benchmark in
+        for _ in benchmark.scaledIterations {
+            let cs: CharacterSet = {
+                var cs = CharacterSet(charactersIn: "a"..."z")
+                cs.insert(charactersIn: "A"..."Z")
+                cs.insert(
+                    charactersIn:
+                        "_\u{00A8}\u{00AA}\u{00AD}\u{00AF}\u{00B2}\u{00B3}\u{00B4}\u{00B5}\u{00B7}\u{00B8}\u{00B9}\u{00BA}\u{00BC}\u{00BD}\u{00BE}"
+                )
+                cs.insert(charactersIn: "\u{00C0}"..."\u{00D6}")
+                cs.insert(charactersIn: "\u{00D8}"..."\u{00F6}")
+                cs.insert(charactersIn: "\u{00F8}"..."\u{00FF}")
+                cs.insert(charactersIn: "\u{0100}"..."\u{02FF}")
+                cs.insert(charactersIn: "\u{0370}"..."\u{167F}")
+                cs.insert(charactersIn: "\u{1681}"..."\u{180D}")
+                cs.insert(charactersIn: "\u{180F}"..."\u{1DBF}")
+                cs.insert(charactersIn: "\u{1E00}"..."\u{1FFF}")
+                cs.insert(charactersIn: "\u{200B}"..."\u{200D}")
+                cs.insert(charactersIn: "\u{202A}"..."\u{202E}")
+                cs.insert(charactersIn: "\u{203F}"..."\u{2040}")
+                cs.insert(charactersIn: "\u{2054}")
+                cs.insert(charactersIn: "\u{2060}"..."\u{206F}")
+                cs.insert(charactersIn: "\u{2070}"..."\u{20CF}")
+                cs.insert(charactersIn: "\u{2100}"..."\u{218F}")
+                cs.insert(charactersIn: "\u{2460}"..."\u{24FF}")
+                cs.insert(charactersIn: "\u{2776}"..."\u{2793}")
+                cs.insert(charactersIn: "\u{2C00}"..."\u{2DFF}")
+                cs.insert(charactersIn: "\u{2E80}"..."\u{2FFF}")
+                cs.insert(charactersIn: "\u{3004}"..."\u{3007}")
+                cs.insert(charactersIn: "\u{3021}"..."\u{302F}")
+                cs.insert(charactersIn: "\u{3031}"..."\u{303F}")
+                cs.insert(charactersIn: "\u{3040}"..."\u{D7FF}")
+                cs.insert(charactersIn: "\u{F900}"..."\u{FD3D}")
+                cs.insert(charactersIn: "\u{FD40}"..."\u{FDCF}")
+                cs.insert(charactersIn: "\u{FDF0}"..."\u{FE1F}")
+                cs.insert(charactersIn: "\u{FE30}"..."\u{FE44}")
+                cs.insert(charactersIn: "\u{FE47}"..."\u{FFFD}")
+                cs.insert(charactersIn: "\u{10000}"..."\u{1FFFD}")
+                cs.insert(charactersIn: "\u{20000}"..."\u{2FFFD}")
+                cs.insert(charactersIn: "\u{30000}"..."\u{3FFFD}")
+                cs.insert(charactersIn: "\u{40000}"..."\u{4FFFD}")
+                cs.insert(charactersIn: "\u{50000}"..."\u{5FFFD}")
+                cs.insert(charactersIn: "\u{60000}"..."\u{6FFFD}")
+                cs.insert(charactersIn: "\u{70000}"..."\u{7FFFD}")
+                cs.insert(charactersIn: "\u{80000}"..."\u{8FFFD}")
+                cs.insert(charactersIn: "\u{90000}"..."\u{9FFFD}")
+                cs.insert(charactersIn: "\u{A0000}"..."\u{AFFFD}")
+                cs.insert(charactersIn: "\u{B0000}"..."\u{BFFFD}")
+                cs.insert(charactersIn: "\u{C0000}"..."\u{CFFFD}")
+                cs.insert(charactersIn: "\u{D0000}"..."\u{DFFFD}")
+                cs.insert(charactersIn: "\u{E0000}"..."\u{EFFFD}")
+                return cs
+            }()
+            var hasher = Hasher()
+            cs.hash(into: &hasher)
+            blackHole(hasher.finalize())
+        }
+    }
+    
+    Benchmark("CharacterSet: Hash Almost Everything") { benchmark in
+        for _ in benchmark.scaledIterations {
+            let cs: CharacterSet = {
+                var characterSet = CharacterSet(charactersIn: "\u{0000}"..."\u{10FFFF}")
+                characterSet.remove(charactersIn: "\"\\\n\r\t\u{0008}\u{000C}")
+                return characterSet
+            }()
+            var hasher = Hasher()
+            cs.hash(into: &hasher)
+            blackHole(hasher.finalize())
+        }
+    }
+    
+    let csSample1: CharacterSet = {
+        var cs = CharacterSet(charactersIn: "a"..."z")
+        cs.insert(charactersIn: "A"..."Z")
+        cs.insert(charactersIn: "\u{10000}"..."\u{1FFFD}")
+        cs.insert(charactersIn: "\u{20000}"..."\u{2FFFD}")
+        return cs
+    }()
+    let csSample1Copy = csSample1
+    Benchmark("CharacterSet: Equal between Two Bitmaps") { benchmark in
+        for _ in benchmark.scaledIterations {
+            blackHole(csSample1 == csSample1Copy)
+        }
+    }
+    
+    let csSample2: CharacterSet = {
+        var cs = CharacterSet(charactersIn: "ABC")
+        cs.invert()
+        return cs
+    }()
+    let csSample3: CharacterSet = {
+        var cs = CharacterSet(charactersIn: "\u{0000}"..."\u{10FFFF}")
+        cs.remove(charactersIn: "ABC")
+        return cs
+    }()
+    Benchmark("CharacterSet: Equal between Bitmap and String") { benchmark in
+        for _ in benchmark.scaledIterations {
+            blackHole(csSample2 == csSample3)
+        }
+    }
+    
+    let csSample4: CharacterSet = {
+        var cs = CharacterSet(charactersIn: "a"..."z")
+        cs.insert(charactersIn: "A"..."Z")
+        cs.insert(charactersIn: "\u{10000}"..."\u{1FFFD}")
+        return cs
+    }()
+    Benchmark("CharacterSet: Not Equal between Two Bitmaps") { benchmark in
+        for _ in benchmark.scaledIterations {
+            blackHole(csSample1 == csSample4)
+        }
+    }
+    
+    let csSample5: CharacterSet = {
+        var cs = CharacterSet(charactersIn: "Hello, World!")
+        return cs
+    }()
+    Benchmark("CharacterSet: Not Equal Between Bitmap and String") { benchmark in
+        for _ in benchmark.scaledIterations {
+            blackHole(csSample1 == csSample5)
+        }
+    }
+    
+    Benchmark("CharacterSet: Bitmap Representation of Small CharacterSet") { benchmark in
+        for _ in benchmark.scaledIterations {
+            blackHole(csSample1.bitmapRepresentation)
+        }
+    }
+    
+    let csSample6: CharacterSet = {
+        var cs = CharacterSet(charactersIn: "a"..."z")
+        cs.insert(charactersIn: "A"..."Z")
+        cs.insert(
+            charactersIn:
+                "_\u{00A8}\u{00AA}\u{00AD}\u{00AF}\u{00B2}\u{00B3}\u{00B4}\u{00B5}\u{00B7}\u{00B8}\u{00B9}\u{00BA}\u{00BC}\u{00BD}\u{00BE}"
+        )
+        cs.insert(charactersIn: "\u{00C0}"..."\u{00D6}")
+        cs.insert(charactersIn: "\u{00D8}"..."\u{00F6}")
+        cs.insert(charactersIn: "\u{00F8}"..."\u{00FF}")
+        cs.insert(charactersIn: "\u{0100}"..."\u{02FF}")
+        cs.insert(charactersIn: "\u{0370}"..."\u{167F}")
+        cs.insert(charactersIn: "\u{1681}"..."\u{180D}")
+        cs.insert(charactersIn: "\u{180F}"..."\u{1DBF}")
+        cs.insert(charactersIn: "\u{1E00}"..."\u{1FFF}")
+        cs.insert(charactersIn: "\u{200B}"..."\u{200D}")
+        cs.insert(charactersIn: "\u{202A}"..."\u{202E}")
+        cs.insert(charactersIn: "\u{203F}"..."\u{2040}")
+        cs.insert(charactersIn: "\u{2054}")
+        cs.insert(charactersIn: "\u{2060}"..."\u{206F}")
+        cs.insert(charactersIn: "\u{2070}"..."\u{20CF}")
+        cs.insert(charactersIn: "\u{2100}"..."\u{218F}")
+        cs.insert(charactersIn: "\u{2460}"..."\u{24FF}")
+        cs.insert(charactersIn: "\u{2776}"..."\u{2793}")
+        cs.insert(charactersIn: "\u{2C00}"..."\u{2DFF}")
+        cs.insert(charactersIn: "\u{2E80}"..."\u{2FFF}")
+        cs.insert(charactersIn: "\u{3004}"..."\u{3007}")
+        cs.insert(charactersIn: "\u{3021}"..."\u{302F}")
+        cs.insert(charactersIn: "\u{3031}"..."\u{303F}")
+        cs.insert(charactersIn: "\u{3040}"..."\u{D7FF}")
+        cs.insert(charactersIn: "\u{F900}"..."\u{FD3D}")
+        cs.insert(charactersIn: "\u{FD40}"..."\u{FDCF}")
+        cs.insert(charactersIn: "\u{FDF0}"..."\u{FE1F}")
+        cs.insert(charactersIn: "\u{FE30}"..."\u{FE44}")
+        cs.insert(charactersIn: "\u{FE47}"..."\u{FFFD}")
+        cs.insert(charactersIn: "\u{10000}"..."\u{1FFFD}")
+        cs.insert(charactersIn: "\u{20000}"..."\u{2FFFD}")
+        cs.insert(charactersIn: "\u{30000}"..."\u{3FFFD}")
+        cs.insert(charactersIn: "\u{40000}"..."\u{4FFFD}")
+        cs.insert(charactersIn: "\u{50000}"..."\u{5FFFD}")
+        cs.insert(charactersIn: "\u{60000}"..."\u{6FFFD}")
+        cs.insert(charactersIn: "\u{70000}"..."\u{7FFFD}")
+        cs.insert(charactersIn: "\u{80000}"..."\u{8FFFD}")
+        cs.insert(charactersIn: "\u{90000}"..."\u{9FFFD}")
+        cs.insert(charactersIn: "\u{A0000}"..."\u{AFFFD}")
+        cs.insert(charactersIn: "\u{B0000}"..."\u{BFFFD}")
+        cs.insert(charactersIn: "\u{C0000}"..."\u{CFFFD}")
+        cs.insert(charactersIn: "\u{D0000}"..."\u{DFFFD}")
+        cs.insert(charactersIn: "\u{E0000}"..."\u{EFFFD}")
+        return cs
+    }()
+    Benchmark("CharacterSet: Bitmap Representation of Large CharacterSet") { benchmark in
+        for _ in benchmark.scaledIterations {
+            blackHole(csSample6.bitmapRepresentation)
+        }
+    }
+    
+    let csSample7: CharacterSet = {
+        var characterSet = CharacterSet(charactersIn: "\u{0000}"..."\u{10FFFF}")
+        characterSet.remove(charactersIn: "\"\\\n\r\t\u{0008}\u{000C}")
+        return characterSet
+    }()
+    Benchmark("CharacterSet: Bitmap Representation of Almost Everything") { benchmark in
+        for _ in benchmark.scaledIterations {
+            blackHole(csSample7.bitmapRepresentation)
+        }
+    }
     #endif // FOUNDATION_FRAMEWORK
 }