[embedded] Make RNG APIs available on embedded Swift

stdlib/public/core/Bool.swift

@@ -133,7 +133,6 @@ public struct Bool: Sendable {
   /// - Returns: Either `true` or `false`, randomly chosen with equal
   ///   probability.
   @inlinable
-  @_unavailableInEmbedded
   public static func random() -> Bool {
     var g = SystemRandomNumberGenerator()
     return Bool.random(using: &g)

stdlib/public/core/Collection.swift

@@ -951,7 +951,6 @@ extension Collection {
   ///   `RandomAccessCollection`; otherwise, O(*n*), where *n* is the length
   ///   of the collection.
   @inlinable
-  @_unavailableInEmbedded
   public func randomElement() -> Element? {
     var g = SystemRandomNumberGenerator()
     return randomElement(using: &g)

stdlib/public/core/CollectionAlgorithms.swift

@@ -571,7 +571,6 @@ extension Sequence {
   ///
   /// - Complexity: O(*n*), where *n* is the length of the sequence.
   @inlinable
-  @_unavailableInEmbedded
   public func shuffled() -> [Element] {
     var g = SystemRandomNumberGenerator()
     return shuffled(using: &g)
@@ -630,7 +629,6 @@ extension MutableCollection where Self: RandomAccessCollection {
   ///
   /// - Complexity: O(*n*), where *n* is the length of the collection.
   @inlinable
-  @_unavailableInEmbedded
   public mutating func shuffle() {
     var g = SystemRandomNumberGenerator()
     shuffle(using: &g)

stdlib/public/core/FloatingPointRandom.swift

@@ -108,7 +108,6 @@ extension BinaryFloatingPoint where Self.RawSignificand: FixedWidthInteger {
   ///   `range` must be finite and non-empty.
   /// - Returns: A random value within the bounds of `range`.
   @inlinable
-  @_unavailableInEmbedded
   public static func random(in range: Range<Self>) -> Self {
     var g = SystemRandomNumberGenerator()
     return Self.random(in: range, using: &g)
@@ -209,7 +208,6 @@ extension BinaryFloatingPoint where Self.RawSignificand: FixedWidthInteger {
   /// - Parameter range: The range in which to create a random value. Must be finite.
   /// - Returns: A random value within the bounds of `range`.
   @inlinable
-  @_unavailableInEmbedded
   public static func random(in range: ClosedRange<Self>) -> Self {
     var g = SystemRandomNumberGenerator()
     return Self.random(in: range, using: &g)

stdlib/public/core/Integers.swift

@@ -2694,7 +2694,6 @@ extension FixedWidthInteger {
   ///   `range` must not be empty.
   /// - Returns: A random value within the bounds of `range`.
   @inlinable
-  @_unavailableInEmbedded
   public static func random(in range: Range<Self>) -> Self {
     var g = SystemRandomNumberGenerator()
     return Self.random(in: range, using: &g)
@@ -2767,7 +2766,6 @@ extension FixedWidthInteger {
   /// - Parameter range: The range in which to create a random value.
   /// - Returns: A random value within the bounds of `range`.
   @inlinable
-  @_unavailableInEmbedded
   public static func random(in range: ClosedRange<Self>) -> Self {
     var g = SystemRandomNumberGenerator()
     return Self.random(in: range, using: &g)

stdlib/public/core/Random.swift

@@ -147,7 +147,6 @@ extension RandomNumberGenerator {
 ///   from `/dev/urandom`.
 /// - Windows uses `BCryptGenRandom`.
 @frozen
-@_unavailableInEmbedded
 public struct SystemRandomNumberGenerator: RandomNumberGenerator, Sendable {
   /// Creates a new instance of the system's default random number generator.
   @inlinable

stdlib/public/core/SIMDVector.swift

@@ -565,7 +565,6 @@ extension SIMD where Scalar: FixedWidthInteger {
 
   /// Returns a vector with random values from within the specified range in
   /// all lanes, using the given generator as a source for randomness.
-  @_unavailableInEmbedded
   @inlinable
   public static func random<T: RandomNumberGenerator>(
     in range: Range<Scalar>,
@@ -580,7 +579,6 @@ extension SIMD where Scalar: FixedWidthInteger {
 
   /// Returns a vector with random values from within the specified range in
   /// all lanes.
-  @_unavailableInEmbedded
   @inlinable
   public static func random(in range: Range<Scalar>) -> Self {
     var g = SystemRandomNumberGenerator()
@@ -589,7 +587,6 @@ extension SIMD where Scalar: FixedWidthInteger {
 
   /// Returns a vector with random values from within the specified range in
   /// all lanes, using the given generator as a source for randomness.
-  @_unavailableInEmbedded
   @inlinable
   public static func random<T: RandomNumberGenerator>(
     in range: ClosedRange<Scalar>,
@@ -604,7 +601,6 @@ extension SIMD where Scalar: FixedWidthInteger {
 
   /// Returns a vector with random values from within the specified range in
   /// all lanes.
-  @_unavailableInEmbedded
   @inlinable
   public static func random(in range: ClosedRange<Scalar>) -> Self {
     var g = SystemRandomNumberGenerator()
@@ -637,7 +633,6 @@ extension SIMD where Scalar: FloatingPoint {
   }
 }
 
-@_unavailableInEmbedded
 extension SIMD
 where Scalar: BinaryFloatingPoint, Scalar.RawSignificand: FixedWidthInteger {
   /// Returns a vector with random values from within the specified range in
@@ -725,7 +720,6 @@ public struct SIMDMask<Storage>: SIMD
   }
 }
 
-@_unavailableInEmbedded
 extension SIMDMask {
   /// Returns a vector mask with `true` or `false` randomly assigned in each
   /// lane, using the given generator as a source for randomness.

test/embedded/Inputs/linux-rng-support.c

@@ -0,0 +1,26 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <stdint.h>
+
+#ifdef __linux__ 
+
+ssize_t getrandom(void *buf, size_t len, unsigned int flags);
+
+void arc4random_buf(void *buf, size_t nbytes) {
+  while (nbytes > 0) {
+    ssize_t actual_nbytes = 0;
+    do {
+    	actual_nbytes = getrandom(buf, nbytes, 0);
+    } while (actual_nbytes == -1 && errno == EINTR);
+
+    if (actual_nbytes == -1) {
+      abort();
+    }
+
+    buf = (uint8_t *)(buf) + actual_nbytes;
+    nbytes -= actual_nbytes;
+  }
+}
+
+#endif

test/embedded/dependencies-random.swift

@@ -0,0 +1,74 @@
+// RUN: %empty-directory(%t)
+// RUN: %target-swift-frontend -parse-as-library -enable-experimental-feature Embedded %s -c -o %t/a.o
+
+// RUN: grep DEP\: %s | sed 's#// DEP\: ##' | sort > %t/allowed-dependencies.txt
+
+// Linux/ELF doesn't use the "_" prefix in symbol mangling.
+// RUN: if [ %target-os == "linux-gnu" ]; then sed -E -i -e 's/^_(.*)$/\1/' %t/allowed-dependencies.txt; fi
+
+// RUN: %llvm-nm --undefined-only --format=just-symbols %t/a.o | sort | tee %t/actual-dependencies.txt
+
+// Fail if there is any entry in actual-dependencies.txt that's not in allowed-dependencies.txt
+// RUN: test -z "`comm -13 %t/allowed-dependencies.txt %t/actual-dependencies.txt`"
+
+// DEP: ___stack_chk_fail
+// DEP: ___stack_chk_guard
+// DEP: _arc4random_buf
+// DEP: _free
+// DEP: _memset
+// DEP: _putchar
+// DEP: _posix_memalign
+
+// RUN: %target-clang -x c -c %S/Inputs/print.c -o %t/print.o
+// RUN: %target-clang -x c -c %S/Inputs/linux-rng-support.c -o %t/linux-rng-support.o
+// RUN: %target-clang %t/a.o %t/print.o %t/linux-rng-support.o -o %t/a.out
+// RUN: %target-run %t/a.out | %FileCheck %s
+
+// REQUIRES: swift_in_compiler
+// REQUIRES: executable_test
+// REQUIRES: optimized_stdlib
+// REQUIRES: OS=macosx || OS=linux-gnu
+// UNSUPPORTED: OS=linux-gnu && CPU=aarch64
+
+@_silgen_name("putchar")
+@discardableResult
+func putchar(_: CInt) -> CInt
+
+public func print(_ s: StaticString, terminator: StaticString = "\n") {
+  var p = s.utf8Start
+  while p.pointee != 0 {
+    putchar(CInt(p.pointee))
+    p += 1
+  }
+  p = terminator.utf8Start
+  while p.pointee != 0 {
+    putchar(CInt(p.pointee))
+    p += 1
+  }
+}
+
+class MyClass {
+  func foo() { print("MyClass.foo") }
+}
+
+class MySubClass: MyClass {
+  override func foo() { print("MySubClass.foo") }
+}
+
+@main
+struct Main {
+  static var objects: [MyClass] = []
+  static func main() {
+    print("Hello Embedded Swift!")
+    // CHECK: Hello Embedded Swift!
+    objects.append(MyClass())
+    objects.append(MySubClass())
+    for o in objects {
+      o.foo()
+    }
+    // CHECK: MyClass.foo
+    // CHECK: MySubClass.foo
+    print(Bool.random() ? "you won" : "you lost")
+    // CHECK: you {{won|lost}}
+  }
+}

test/embedded/stdlib-array.swift

@@ -21,9 +21,9 @@ public func test() {
   array.max()
   array.partition(by: { $0 > 0 })
   array.reduce(0, +)
-  // array.shuffle()
-  // array = array.shuffled()
-  // array.randomElement()
+  array.shuffle()
+  array = array.shuffled()
+  array.randomElement()
 }
 
 test()

test/embedded/stdlib-random.swift

@@ -0,0 +1,17 @@
+// RUN: %target-swift-frontend -target armv7-apple-none-macho -Xcc -D__MACH__ -emit-ir %s -enable-experimental-feature Embedded | %FileCheck %s
+// RUN: %target-swift-frontend -target arm64-apple-none-macho -Xcc -D__MACH__ -Xcc -D__arm64__ -Xcc -D__APPLE__ -emit-ir %s -enable-experimental-feature Embedded | %FileCheck %s
+
+// REQUIRES: swift_in_compiler
+// REQUIRES: optimized_stdlib
+
+public func test() {
+  Bool.random()
+  Int.random(in: 0 ..< 100)
+  Double.random(in: 0.0 ..< 1.0)
+  [1, 2, 3].shuffled()
+  [1, 2, 3].randomElement()
+}
+
+test()
+
+// CHECK: define {{.*}}i32 @main(i32 %0, ptr %1)

test/embedded/stdlib-set.swift

@@ -17,8 +17,8 @@ public func test() {
   s.min()
   s.max()
   s.reduce(0, +)
-  // s.shuffled()
-  // s.randomElement()
+  s.shuffled()
+  s.randomElement()
 }
 
 test()