swiftlang · pschuh · Sep 24, 2020 · Sep 17, 2020 · Sep 17, 2020 · Sep 17, 2020
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -4,24 +4,23 @@ CHANGELOG
 <details>
 <summary>Note: This is in reverse chronological order, so newer entries are added to the top.</summary>
 
-| Version                   | Released   | Toolchain   |
-| :------------------------ | :--------- | :---------- |
-| [Swift Next](#swift-next) |
-| [Swift 5.3](#swift-53)    |            |             |
-| [Swift 5.2](#swift-52)    | 2020-03-24 | Xcode 11.4  |
-| [Swift 5.1](#swift-51)    | 2019-09-20 | Xcode 11.0  |
-| [Swift 5.0](#swift-50)    | 2019-03-25 | Xcode 10.2  |
-| [Swift 4.2](#swift-42)    | 2018-09-17 | Xcode 10.0  |
-| [Swift 4.1](#swift-41)    | 2018-03-29 | Xcode 9.3   |
-| [Swift 4.0](#swift-40)    | 2017-09-19 | Xcode 9.0   |
-| [Swift 3.1](#swift-31)    | 2017-03-27 | Xcode 8.3   |
-| [Swift 3.0](#swift-30)    | 2016-09-13 | Xcode 8.0   |
-| [Swift 2.2](#swift-22)    | 2016-03-21 | Xcode 7.3   |
-| [Swift 2.1](#swift-21)    | 2015-10-21 | Xcode 7.1   |
-| [Swift 2.0](#swift-20)    | 2015-09-17 | Xcode 7.0   |
-| [Swift 1.2](#swift-12)    | 2015-04-08 | Xcode 6.3   |
-| [Swift 1.1](#swift-11)    | 2014-12-02 | Xcode 6.1.1 |
-| [Swift 1.0](#swift-10)    | 2014-09-15 | Xcode 6.0   |
+| Version                | Released   | Toolchain   |
+| :--------------------- | :--------- | :---------- |
+| [Swift 5.3](#swift-53) | 2020-09-16 | Xcode 12.0  |
+| [Swift 5.2](#swift-52) | 2020-03-24 | Xcode 11.4  |
+| [Swift 5.1](#swift-51) | 2019-09-20 | Xcode 11.0  |
+| [Swift 5.0](#swift-50) | 2019-03-25 | Xcode 10.2  |
+| [Swift 4.2](#swift-42) | 2018-09-17 | Xcode 10.0  |
+| [Swift 4.1](#swift-41) | 2018-03-29 | Xcode 9.3   |
+| [Swift 4.0](#swift-40) | 2017-09-19 | Xcode 9.0   |
+| [Swift 3.1](#swift-31) | 2017-03-27 | Xcode 8.3   |
+| [Swift 3.0](#swift-30) | 2016-09-13 | Xcode 8.0   |
+| [Swift 2.2](#swift-22) | 2016-03-21 | Xcode 7.3   |
+| [Swift 2.1](#swift-21) | 2015-10-21 | Xcode 7.1   |
+| [Swift 2.0](#swift-20) | 2015-09-17 | Xcode 7.0   |
+| [Swift 1.2](#swift-12) | 2015-04-08 | Xcode 6.3   |
+| [Swift 1.1](#swift-11) | 2014-12-02 | Xcode 6.1.1 |
+| [Swift 1.0](#swift-10) | 2014-09-15 | Xcode 6.0   |
 
 </details>
 
@@ -80,9 +79,13 @@ Swift Next
   let _: Foo? = .bar.anotherFoo.getFoo().optionalFoo?.optionalFoo![]
   ```
 
+**Add new entries to the top of this section, not here!**
+
 Swift 5.3
 ---------
 
+### 2020-09-16 (Xcode 12.0)
+
 * [SE-0279][] & [SE-0286][]:
 
   Trailing closure syntax has been extended to allow additional labeled closures to follow the initial unlabeled closure:

diff --git a/CMakeLists.txt b/CMakeLists.txt
@@ -248,10 +248,6 @@ set(SWIFT_NATIVE_CLANG_TOOLS_PATH "" CACHE STRING
 set(SWIFT_NATIVE_SWIFT_TOOLS_PATH "" CACHE STRING
    "Path to the directory that contains Swift tools that are executable on the build machine")
 
-option(SWIFT_ENABLE_MODULE_INTERFACES
-       "Generate .swiftinterface files alongside .swiftmodule files"
-       TRUE)
-
 option(SWIFT_STDLIB_ENABLE_SIB_TARGETS
        "Should we generate sib targets for the stdlib or not?"
        FALSE)

diff --git a/README.md b/README.md
@@ -5,7 +5,7 @@
 | **macOS** | Google Kokoro | ![Build Status](https://storage.googleapis.com/tensorflow-kokoro-build-badges/macos-swift-tf-release.svg) | - |
 | **Ubuntu 16.04** | Swift.org CI | [![Build Status](https://ci-external.swift.org/job/oss-swift-RA-linux-ubuntu-16.04-tensorflow/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-RA-linux-ubuntu-16.04-tensorflow) | [![Build Status](https://ci-external.swift.org/job/oss-swift-RA-linux-ubuntu-16.04-tensorflow-gpu/lastCompletedBuild/badge/icon)](https://ci-external.swift.org/job/oss-swift-RA-linux-ubuntu-16.04-tensorflow-gpu) |
 
-| | **Architecture** | **Master** | **Package** |
+| | **Architecture** | **main** | **Package** |
 |---|:---:|:---:|:---:|
 | **macOS**        | x86_64 |[![Build Status](https://ci.swift.org/job/oss-swift-incremental-RA-osx/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-incremental-RA-osx)|[![Build Status](https://ci.swift.org/job/oss-swift-package-osx/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-osx)|
 | **Ubuntu 16.04** | x86_64 | [![Build Status](https://ci.swift.org/job/oss-swift-incremental-RA-linux-ubuntu-16_04/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-incremental-RA-linux-ubuntu-16_04)|[![Build Status](https://ci.swift.org/job/oss-swift-package-linux-ubuntu-16_04/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-linux-ubuntu-16_04)|

diff --git a/benchmark/README.md b/benchmark/README.md
@@ -8,11 +8,11 @@ To run Swift benchmarks, pass the `--benchmark` flag to `build-script`. The
 current benchmark results will be compared to the previous run's results if
 available. Results for each benchmark run are logged for future comparison.
 
-For branch based development, take a baseline benchmark on the Swift `master`
+For branch based development, take a baseline benchmark on the Swift `main`
 branch, switch to a development branch containing potentially performance
 impacting changes, and run the benchmarks again. Upon benchmark completion, the
 benchmark results for the development branch will be compared to the most
-recent benchmark results for `master`.
+recent benchmark results for `main`.
 
 ## Building the Swift Benchmarks
 
@@ -181,7 +181,7 @@ benchmarks will be compiled with -Onone!**
 * `--list`
     * Print a list of available tests matching specified criteria
 * `--tags`
-    * Run tests that are labeled with specified [tags](https://github.com/apple/swift/blob/master/benchmark/utils/TestsUtils.swift#L19)
+    * Run tests that are labeled with specified [tags](https://github.com/apple/swift/blob/main/benchmark/utils/TestsUtils.swift#L19)
      (comma separated list); multiple tags are interpreted as logical AND, i.e.
      run only test that are labeled with all the supplied tags
 * `--skip-tags`

diff --git a/benchmark/scripts/Benchmark_Driver b/benchmark/scripts/Benchmark_Driver
@@ -975,9 +975,9 @@ def parse_args(args):
     )
     compare_parser.add_argument(
         "--baseline-branch",
-        default="master",
+        default="main",
         help="attempt to compare results to baseline results for specified "
-        "branch (default: master)",
+        "branch (default: main)",
     )
     compare_parser.set_defaults(func=compare)
 

diff --git a/benchmark/scripts/Benchmark_RuntimeLeaksRunner.in b/benchmark/scripts/Benchmark_RuntimeLeaksRunner.in
@@ -62,12 +62,13 @@ class LeaksRunnerResult(perf_test_driver.Result):
 
 
 class LeaksRunnerBenchmarkDriver(perf_test_driver.BenchmarkDriver):
-    def __init__(self, binary, xfail_list, num_samples, num_iters):
+    def __init__(self, binary, xfail_list, num_samples, num_iters, verbose):
         perf_test_driver.BenchmarkDriver.__init__(
             self, binary, xfail_list, enable_parallel=True
         )
         self.num_samples = num_samples
         self.num_iters = num_iters
+        self.verbose = verbose
 
     def print_data_header(self, max_test_len):
         fmt = "{:<%d}{:<10}{:}" % (max_test_len + 5)
@@ -120,6 +121,13 @@ class LeaksRunnerBenchmarkDriver(perf_test_driver.BenchmarkDriver):
             ]
             d["objc_count"] = len(d["objc_objects"])
 
+            # If we are asked to emit verbose output, do so now.
+            if self.verbose:
+                tmp = (data["path"], data["test_name"], d)
+                sys.stderr.write(
+                    "VERBOSE (%s,%s): %s" % tmp)
+                sys.stderr.flush()
+
             total_count = d["objc_count"] + d["swift_count"]
             return total_count
         except Exception:
@@ -156,13 +164,17 @@ def parse_args():
     )
     parser.add_argument("-num-samples", type=int, default=2)
     parser.add_argument("-num-iters", type=int, default=2)
+    parser.add_argument("-v", "--verbose", action="store_true",
+                        help="Upon failure, dump out raw result",
+                        dest="verbose")
     return parser.parse_args()
 
 
 if __name__ == "__main__":
     args = parse_args()
     driver = LeaksRunnerBenchmarkDriver(
-        SWIFT_BIN_DIR, XFAIL_LIST, args.num_samples, args.num_iters
+        SWIFT_BIN_DIR, XFAIL_LIST, args.num_samples, args.num_iters,
+        args.verbose
     )
     if driver.run(args.filter):
         sys.exit(0)

diff --git a/benchmark/single-source/ChaCha.swift b/benchmark/single-source/ChaCha.swift
@@ -22,6 +22,7 @@ import TestsUtils
 enum ChaCha20 { }
 
 extension ChaCha20 {
+    @inline(never)
     public static func encrypt<Key: Collection, Nonce: Collection, Bytes: MutableCollection>(bytes: inout Bytes, key: Key, nonce: Nonce, initialCounter: UInt32 = 0) where Bytes.Element == UInt8, Key.Element == UInt8, Nonce.Element == UInt8 {
         var baseState = ChaChaState(key: key, nonce: nonce, counter: initialCounter)
         var index = bytes.startIndex
@@ -347,13 +348,28 @@ public let ChaCha = BenchmarkInfo(
   runFunction: run_ChaCha,
   tags: [.runtime, .cpubench])
 
+@inline(never)
+func checkResult(_ plaintext: [UInt8]) {
+    CheckResults(plaintext.first! == 6 && plaintext.last! == 254)
+    var hash: UInt64 = 0
+    for byte in plaintext {
+        // rotate
+        hash = (hash &<< 8) | (hash &>> (64 - 8))
+        hash ^= UInt64(byte)
+    }
+    CheckResults(hash == 0xa1bcdb217d8d14e4)
+}
 
 @inline(never)
 public func run_ChaCha(_ N: Int) {
-  var plaintext = Array(repeating: UInt8(0), count: 30720)  // Chosen for CI runtime
   let key = Array(repeating: UInt8(1), count: 32)
   let nonce = Array(repeating: UInt8(2), count: 12)
 
+  var checkedtext = Array(repeating: UInt8(0), count: 1024)
+  ChaCha20.encrypt(bytes: &checkedtext, key: key, nonce: nonce)
+  checkResult(checkedtext)
+
+  var plaintext = Array(repeating: UInt8(0), count: 30720)  // Chosen for CI runtime
   for _ in 1...N {
     ChaCha20.encrypt(bytes: &plaintext, key: key, nonce: nonce)
     blackHole(plaintext.first!)

diff --git a/benchmark/single-source/FloatingPointConversion.swift b/benchmark/single-source/FloatingPointConversion.swift
@@ -18,6 +18,21 @@ public let FloatingPointConversion = [
     runFunction: run_ConvertFloatingPoint_MockFloat64ToDouble,
     tags: [.validation, .api],
     setUpFunction: { blackHole(mockFloat64s) }),
+  BenchmarkInfo(
+    name: "ConvertFloatingPoint.MockFloat64Exactly",
+    runFunction: run_ConvertFloatingPoint_MockFloat64Exactly,
+    tags: [.validation, .api],
+    setUpFunction: { blackHole(mockFloat64s) }),
+  BenchmarkInfo(
+    name: "ConvertFloatingPoint.MockFloat64Exactly2",
+    runFunction: run_ConvertFloatingPoint_MockFloat64Exactly2,
+    tags: [.validation, .api],
+    setUpFunction: { blackHole(mockFloat64s) }),
+  BenchmarkInfo(
+    name: "ConvertFloatingPoint.MockFloat64ToInt64",
+    runFunction: run_ConvertFloatingPoint_MockFloat64ToInt64,
+    tags: [.validation, .api],
+    setUpFunction: { blackHole(mockFloat64s) }),
 ]
 
 protocol MockBinaryFloatingPoint: BinaryFloatingPoint {
@@ -125,6 +140,11 @@ struct MockFloat64: MockBinaryFloatingPoint {
   init(_ _value: Double) { self._value = _value }
 }
 
+struct MockFloat32: MockBinaryFloatingPoint {
+  var _value: Float
+  init(_ _value: Float) { self._value = _value }
+}
+
 let doubles = [
    1.8547832857295,  26.321549267719135, 98.9544480962058,    73.70286973782363,
   82.04918555938816, 76.38902969312758,  46.35647857011161,   64.0821426030317,
@@ -142,21 +162,51 @@ let doubles = [
 
 let mockFloat64s = doubles.map { MockFloat64($0) }
 
+// See also: test/SILOptimizer/floating_point_conversion.swift
+
+@inline(never)
+public func run_ConvertFloatingPoint_MockFloat64ToDouble(_ N: Int) {
+  for _ in 0..<(N * 100) {
+    for element in mockFloat64s {
+      let f = Double(identity(element))
+      blackHole(f)
+    }
+  }
+}
+
 @inline(__always)
 func convert<
   T: BinaryFloatingPoint, U: BinaryFloatingPoint
->(_ value: T, to: U.Type) -> U {
-  U(value)
+>(exactly value: T, to: U.Type) -> U? {
+  U(exactly: value)
 }
 
-// See also: test/SILOptimizer/floating_point_conversion.swift
+@inline(never)
+public func run_ConvertFloatingPoint_MockFloat64Exactly(_ N: Int) {
+  for _ in 0..<(N * 25) {
+    for element in mockFloat64s {
+      let f = convert(exactly: identity(element), to: Double.self)
+      blackHole(f)
+    }
+  }
+}
 
 @inline(never)
-public func run_ConvertFloatingPoint_MockFloat64ToDouble(_ N: Int) {
-  for _ in 0..<(N * 100) {
+public func run_ConvertFloatingPoint_MockFloat64Exactly2(_ N: Int) {
+  for _ in 0..<(N * 25) {
     for element in mockFloat64s {
-      let f = Double(identity(element))
+      let f = convert(exactly: identity(element), to: MockFloat32.self)
       blackHole(f)
     }
   }
 }
+
+@inline(never)
+public func run_ConvertFloatingPoint_MockFloat64ToInt64(_ N: Int) {
+  for _ in 0..<(N * 1000) {
+    for element in mockFloat64s {
+      let i = Int64(identity(element))
+      blackHole(i)
+    }
+  }
+}
diff --git a/cmake/modules/DarwinSDKs.cmake b/cmake/modules/DarwinSDKs.cmake
@@ -32,11 +32,14 @@ if(swift_build_freestanding)
       "Which SDK to use when building the FREESTANDING stdlib")
   set(SWIFT_FREESTANDING_TRIPLE_NAME "" CACHE STRING
       "Which triple name (e.g. 'none-macho') to use when building the FREESTANDING stdlib")
+  set(SWIFT_FREESTANDING_MODULE_NAME "" CACHE STRING
+      "Which .swiftmodule name (e.g. 'freestanding') to use when building the FREESTANDING stdlib")
   set(SWIFT_FREESTANDING_ARCHS "" CACHE STRING
       "Which architectures to build when building the FREESTANDING stdlib")
   configure_sdk_darwin(
       FREESTANDING "FREESTANDING" ""
-      "${SWIFT_FREESTANDING_SDK}" freestanding "${SWIFT_FREESTANDING_TRIPLE_NAME}" freestanding "${SWIFT_FREESTANDING_ARCHS}")
+      "${SWIFT_FREESTANDING_SDK}" freestanding
+      "${SWIFT_FREESTANDING_TRIPLE_NAME}" "${SWIFT_FREESTANDING_MODULE_NAME}" "${SWIFT_FREESTANDING_ARCHS}")
   set(SWIFT_SDK_FREESTANDING_LIB_SUBDIR "freestanding")
   configure_target_variant(FREESTANDING-DA "FREESTANDING Debug+Asserts"   FREESTANDING DA "Debug+Asserts")
   configure_target_variant(FREESTANDING-RA "FREESTANDING Release+Asserts" FREESTANDING RA "Release+Asserts")

diff --git a/docs/ABI/RegisterUsage.md b/docs/ABI/RegisterUsage.md
@@ -1,6 +1,6 @@
 ## 64-Bit Architecture Register Usage
 
-From Swift 5, the calling convention register allocation for 64-bit architectures is largely based on [existing](https://developer.apple.com/library/content/documentation/Xcode/Conceptual/iPhoneOSABIReference/Articles/ARM64FunctionCallingConventions.html) [standards](https://developer.apple.com/library/content/documentation/DeveloperTools/Conceptual/LowLevelABI/140-x86-64_Function_Calling_Conventions/x86_64.html), with the addition of the context and error return registers discussed in the [ABI stability manifesto](https://github.com/apple/swift/blob/master/docs/ABIStabilityManifesto.md):
+From Swift 5, the calling convention register allocation for 64-bit architectures is largely based on [existing](https://developer.apple.com/library/content/documentation/Xcode/Conceptual/iPhoneOSABIReference/Articles/ARM64FunctionCallingConventions.html) [standards](https://developer.apple.com/library/content/documentation/DeveloperTools/Conceptual/LowLevelABI/140-x86-64_Function_Calling_Conventions/x86_64.html), with the addition of the context and error return registers discussed in the [ABI stability manifesto](https://github.com/apple/swift/blob/main/docs/ABIStabilityManifesto.md):
 
 | Register Purpose | ARM64 | x86_64 |
 | ------------- |:-------------:| ----- |