Merge pull request #79222 from meg-gupta/boundstestsupdate

[NFC] Update span unit tests for bounds check optimizations

Author: meg-gupta

test/SILOptimizer/Inputs/SpanExtras.swift

@@ -1,41 +1,53 @@
 import Builtin
 
+/// Unsafely discard any lifetime dependency on the `dependent` argument. Return
+/// a value identical to `dependent` with a lifetime dependency on the caller's
+/// borrow scope of the `source` argument.
+@unsafe
 @_unsafeNonescapableResult
-@inlinable @inline(__always)
+@_alwaysEmitIntoClient
+@_transparent
 @lifetime(borrow source)
-public func _overrideLifetime<
-  T: ~Copyable & ~Escapable,
-  U: ~Copyable & ~Escapable
+internal func _overrideLifetime<
+  T: ~Copyable & ~Escapable, U: ~Copyable & ~Escapable
 >(
-  of dependent: consuming T,
-  to source: borrowing U
+  _ dependent: consuming T, borrowing source: borrowing U
 ) -> T {
+  // TODO: Remove @_unsafeNonescapableResult. Instead, the unsafe dependence
+  // should be expressed by a builtin that is hidden within the function body.
   dependent
 }
 
+/// Unsafely discard any lifetime dependency on the `dependent` argument. Return
+/// a value identical to `dependent` that inherits all lifetime dependencies from
+/// the `source` argument.
+@unsafe
 @_unsafeNonescapableResult
-@inlinable @inline(__always)
+@_alwaysEmitIntoClient
+@_transparent
 @lifetime(source)
-public func _overrideLifetime<
-  T: ~Copyable & ~Escapable,
-  U: ~Copyable & ~Escapable
+internal func _overrideLifetime<
+  T: ~Copyable & ~Escapable, U: ~Copyable & ~Escapable
 >(
-  of dependent: consuming T,
-  copyingFrom source: consuming U
+  _ dependent: consuming T, copying source: borrowing U
 ) -> T {
+  // TODO: Remove @_unsafeNonescapableResult. Instead, the unsafe dependence
+  // should be expressed by a builtin that is hidden within the function body.
   dependent
 }
 
+@unsafe
 @_unsafeNonescapableResult
-@inlinable @inline(__always)
+@_alwaysEmitIntoClient
+@_transparent
 @lifetime(source)
-public func _overrideLifetime<
-  T: ~Copyable & ~Escapable,
-  U: ~Copyable & ~Escapable
+internal func _overrideLifetime<
+  T: ~Copyable & ~Escapable, U: ~Copyable & ~Escapable
 >(
-  of dependent: consuming T,
-  mutating source: inout U
+  _ dependent: consuming T, mutating source: inout U
 ) -> T {
+  // TODO: Remove @_unsafeNonescapableResult. Instead, the unsafe dependence
+  // should be expressed by a builtin that is hidden within the function body.
   dependent
 }
 
@@ -91,7 +103,7 @@ extension MutableSpan where Element: ~Copyable {
       "baseAddress must be properly aligned to access Element"
     )
     let ms = MutableSpan<Element>(_unchecked: buffer)
-    self = _overrideLifetime(of: ms, to: buffer)
+    self = _overrideLifetime(ms, borrowing: buffer)
   }
 
   @_alwaysEmitIntoClient
@@ -103,7 +115,7 @@ extension MutableSpan where Element: ~Copyable {
     precondition(count >= 0, "Count must not be negative")
     let buffer = UnsafeMutableBufferPointer(start: start, count: count)
     let ms = MutableSpan(_unsafeElements: buffer)
-    self = _overrideLifetime(of: ms, to: start)
+    self = _overrideLifetime(ms, borrowing: start)
   }
 }
 
@@ -117,7 +129,7 @@ extension MutableSpan {
   ) {
     let rb = UnsafeMutableBufferPointer(rebasing: elements)
     let ms = MutableSpan(_unsafeElements: rb)
-    self = _overrideLifetime(of: ms, to: rb)
+    self = _overrideLifetime(ms, borrowing: rb)
   }
 }
 
@@ -142,7 +154,7 @@ extension MutableSpan where Element: BitwiseCopyable {
       count: count
     )
     let ms = MutableSpan(_unsafeElements: elements)
-    self = _overrideLifetime(of: ms, to: buffer)
+    self = _overrideLifetime(ms, borrowing: buffer)
   }
 
   @_alwaysEmitIntoClient
@@ -154,7 +166,7 @@ extension MutableSpan where Element: BitwiseCopyable {
     precondition(byteCount >= 0, "Count must not be negative")
     let bytes = UnsafeMutableRawBufferPointer(start: pointer, count: byteCount)
     let ms = MutableSpan(_unsafeBytes: bytes)
-    self = _overrideLifetime(of: ms, to: pointer)
+    self = _overrideLifetime(ms, borrowing: pointer)
   }
 
   @_alwaysEmitIntoClient
@@ -164,7 +176,7 @@ extension MutableSpan where Element: BitwiseCopyable {
   ) {
     let bytes = UnsafeMutableRawBufferPointer(rebasing: buffer)
     let ms = MutableSpan(_unsafeBytes: bytes)
-    self = _overrideLifetime(of: ms, to: buffer)
+    self = _overrideLifetime(ms, borrowing: buffer)
   }
 }
 
@@ -176,7 +188,7 @@ extension Span where Element: ~Copyable {
     let pointer = mutableSpan._pointer?.assumingMemoryBound(to: Element.self)
     let buffer = UnsafeBufferPointer(start: pointer, count: mutableSpan.count)
     let span = Span(_unsafeElements: buffer)
-    self = _overrideLifetime(of: span, to: mutableSpan)
+    self = _overrideLifetime(span, borrowing: mutableSpan)
   }
 }
 
@@ -210,7 +222,7 @@ extension RawSpan {
     let byteCount = mutableSpan.count &* MemoryLayout<Element>.stride
     let buffer = UnsafeRawBufferPointer(start: pointer, count: byteCount)
     let rawSpan = RawSpan(_unsafeBytes: buffer)
-    self = _overrideLifetime(of: rawSpan, to: mutableSpan)
+    self = _overrideLifetime(rawSpan, borrowing: mutableSpan)
   }
 }
 
@@ -516,45 +528,7 @@ extension MutableSpan {
 }
 
 @available(macOS 9999, iOS 9999, tvOS 9999, watchOS 9999, visionOS 9999, *)
-extension MutableSpan where Element: ~Copyable {
 
-  @_alwaysEmitIntoClient
-  public mutating func moveUpdate(
-    fromContentsOf source: consuming OutputSpan<Element>
-  ) -> Index {
-    guard !source.isEmpty else { return 0 }
-    precondition(
-      source.count <= self.count,
-      "destination span cannot contain every element from source."
-    )
-    let buffer = source.relinquishBorrowedMemory()
-    // we must now deinitialize the returned UMBP
-    _start().moveInitializeMemory(
-      as: Element.self, from: buffer.baseAddress!, count: buffer.count
-    )
-    return buffer.count
-  }
-
-  public mutating func moveUpdate(
-    fromContentsOf source: UnsafeMutableBufferPointer<Element>
-  ) -> Index {
-    let source = OutputSpan(_initializing: source, initialized: source.count)
-    return self.moveUpdate(fromContentsOf: source)
-  }
-}
-
-@available(macOS 9999, iOS 9999, tvOS 9999, watchOS 9999, visionOS 9999, *)
-extension MutableSpan {
-
-  public mutating func moveUpdate(
-    fromContentsOf source: Slice<UnsafeMutableBufferPointer<Element>>
-  ) -> Index {
-    self.moveUpdate(fromContentsOf: .init(rebasing: source))
-  }
-}
-
-
-@available(macOS 9999, iOS 9999, tvOS 9999, watchOS 9999, visionOS 9999, *)
 extension MutableSpan where Element: BitwiseCopyable {
 
   @_alwaysEmitIntoClient
@@ -686,115 +660,12 @@ public struct OutputSpan<Element: ~Copyable>: ~Copyable, ~Escapable {
 @available(*, unavailable)
 extension OutputSpan: Sendable {}
 
-@available(macOS 9999, iOS 9999, tvOS 9999, watchOS 9999, visionOS 9999, *)
-extension OutputSpan where Element: ~Copyable  {
-
-  @usableFromInline @inline(__always)
-  @lifetime(borrow buffer)
-  init(
-    _unchecked buffer: UnsafeMutableBufferPointer<Element>,
-    initialized: Int
-  ) {
-    _pointer = .init(buffer.baseAddress)
-    capacity = buffer.count
-    _initialized = initialized
-  }
-
-  @_alwaysEmitIntoClient
-  @lifetime(borrow buffer)
-  public init(
-    _initializing buffer: UnsafeMutableBufferPointer<Element>,
-    initialized: Int = 0
-  ) {
-    precondition(
-      ((Int(bitPattern: buffer.baseAddress) &
-        (MemoryLayout<Element>.alignment&-1)) == 0),
-      "baseAddress must be properly aligned to access Element"
-    )
-    self.init(_unchecked: buffer, initialized: initialized)
-  }
-
-  @_alwaysEmitIntoClient
-  @lifetime(borrow pointer)
-  public init(
-    _initializing pointer: UnsafeMutablePointer<Element>,
-    capacity: Int,
-    initialized: Int = 0
-  ) {
-    precondition(capacity >= 0, "Capacity must be 0 or greater")
-    let buffer = UnsafeMutableBufferPointer(start: pointer, count: capacity)
-    let os = OutputSpan(_initializing: buffer, initialized: initialized)
-    self = _overrideLifetime(of: os, to: pointer)
-  }
-}
-
-@available(macOS 9999, iOS 9999, tvOS 9999, watchOS 9999, visionOS 9999, *)
-extension OutputSpan {
-
-  @_alwaysEmitIntoClient
-  @lifetime(borrow buffer)
-  public init(
-    _initializing buffer: borrowing Slice<UnsafeMutableBufferPointer<Element>>,
-    initialized: Int = 0
-  ) {
-    let rebased = UnsafeMutableBufferPointer(rebasing: buffer)
-    let os = OutputSpan(_initializing: rebased, initialized: 0)
-    self = _overrideLifetime(of: os, to: buffer)
-  }
-}
-
-@available(macOS 9999, iOS 9999, tvOS 9999, watchOS 9999, visionOS 9999, *)
-extension OutputSpan where Element: BitwiseCopyable {
-
-  @_alwaysEmitIntoClient
-  @lifetime(borrow bytes)
-  public init(
-    _initializing bytes: UnsafeMutableRawBufferPointer,
-    initialized: Int = 0
-  ) {
-    precondition(
-      ((Int(bitPattern: bytes.baseAddress) &
-        (MemoryLayout<Element>.alignment&-1)) == 0),
-      "baseAddress must be properly aligned to access Element"
-    )
-    let (byteCount, stride) = (bytes.count, MemoryLayout<Element>.stride)
-    let (count, remainder) = byteCount.quotientAndRemainder(dividingBy: stride)
-    precondition(remainder == 0, "Span must contain a whole number of elements")
-    let pointer = bytes.baseAddress
-    let os = OutputSpan(
-      _unchecked: pointer, capacity: count, initialized: initialized
-    )
-    self = _overrideLifetime(of: os, to: bytes)
-  }
-
-  @_alwaysEmitIntoClient
-  @lifetime(borrow pointer)
-  public init(
-    _initializing pointer: UnsafeMutableRawPointer,
-    capacity: Int,
-    initialized: Int = 0
-  ) {
-    precondition(capacity >= 0, "Capacity must be 0 or greater")
-    let buffer = UnsafeMutableRawBufferPointer(start: pointer, count: capacity)
-    let os = OutputSpan(_initializing: buffer, initialized: initialized)
-    self = _overrideLifetime(of: os, to: pointer)
-  }
-
-  @_alwaysEmitIntoClient
-  @lifetime(borrow buffer)
-  public init(
-    _initializing buffer: borrowing Slice<UnsafeMutableRawBufferPointer>,
-    initialized: Int = 0
-  ) {
-    let rebased = UnsafeMutableRawBufferPointer(rebasing: buffer)
-    let os = OutputSpan(_initializing: rebased, initialized: initialized)
-    self = _overrideLifetime(of: os, to: buffer)
-  }
-}
-
 @available(macOS 9999, iOS 9999, tvOS 9999, watchOS 9999, visionOS 9999, *)
 extension OutputSpan where Element: ~Copyable {
 
+@available(macOS 9999, *)
+@available(macOS 9999, *)
+@available(macOS 9999, *)
   @_alwaysEmitIntoClient
   public mutating func append(_ value: consuming Element) {
     precondition(_initialized < capacity, "Output buffer overflow")
@@ -1000,7 +871,7 @@ extension OutputSpan where Element: ~Copyable {
       let pointer = _pointer?.assumingMemoryBound(to: Element.self)
       let buffer = UnsafeBufferPointer(start: pointer, count: _initialized)
       let span = Span(_unsafeElements: buffer)
-      return _overrideLifetime(of: span, to: self)
+      return _overrideLifetime(span, borrowing: self)
     }
   }
 
@@ -1011,7 +882,7 @@ extension OutputSpan where Element: ~Copyable {
       let pointer = _pointer?.assumingMemoryBound(to: Element.self)
       let buffer = UnsafeMutableBufferPointer(start: pointer, count: _initialized)
       let span = MutableSpan(_unsafeElements: buffer)
-      return _overrideLifetime(of: span, mutating: &self)
+      return _overrideLifetime(span, mutating: &self)
     }
   }
 }
@@ -1050,7 +921,7 @@ extension Span {
 //    get {
 //      let nilBasedBuffer = UnsafeBufferPointer<Element>(start: nil, count: 0)
 //      let span = Span(_unsafeElements: nilBasedBuffer)
-//      return _overrideLifetime(of: span, to: immortalThing)
+//      return _overrideLifetime(span, to: immortalThing)
 //    }
 //  }
 //
@@ -1059,7 +930,7 @@ extension Span {
 //  public init() {
 //    let nilBasedBuffer = UnsafeBufferPointer<Element>(start: nil, count: 0)
 //    let span = Span(_unsafeElements: nilBasedBuffer)
-//    self = _overrideLifetime(of: span, to: immortalThing)
+//    self = _overrideLifetime(span, to: immortalThing)
 //  }
 }