Test noescape closure capture lifetimes

Author: atrick

test/SILOptimizer/lifetime_dependence/semantics.swift

@@ -74,6 +74,10 @@ struct MutableSpan<T>: ~Escapable, ~Copyable {
  }
 }
 
+extension MutableSpan {
+ mutating func update() {}
+}
+
 extension Array {
  @_lifetime(borrow self)
  borrowing func span() -> Span<Element> {
@@ -516,6 +520,68 @@ func testReassignToBorrowBad(span: inout Span<Int>, array: [Int]) { // expected-
  reassign(dest: &span, source: array.span())
 } // expected-note{{this use causes the lifetime-dependent value to escape}}
 
+// =============================================================================
+// Copied dependence on mutable captures
+// =============================================================================
+
+func runClosure(_ body: ()->()) {}
+
+func testNoEscapeClosureCaptureMutation(spanArg: consuming MutableSpan<Int>) {
+ var spanCapture = spanArg
+ runClosure {
+ spanCapture.update()
+ }
+ _ = spanCapture
+}
+
+func testNoEscapeClosureCaptureMutationDirect(spanArg: consuming MutableSpan<Int>) {
+ var spanCapture = spanArg;
+ {
+ spanCapture.update()
+ }()
+ _ = spanCapture
+}
+
+func testNoEscapClosureCaptureUnsupported(spanArg: Span<Int>, array: consuming [Int]) {
+ var spanCapture = spanArg // expected-error{{lifetime-dependent variable 'spanCapture' escapes its scope}}
+ // expected-note@-2{{it depends on a closure capture; this is not yet supported}}
+ _ = spanCapture;
+ runClosure {
+ spanCapture = array.span()
+ } // expected-note{{this use causes the lifetime-dependent value to escape}}
+}
+
+func testNoEscapClosureCaptureUnsupportedDirect(spanArg: Span<Int>, array: consuming [Int]) {
+ var spanCapture = spanArg // expected-error{{lifetime-dependent variable 'spanCapture' escapes its scope}}
+ // expected-note@-2{{it depends on a closure capture; this is not yet supported}}
+ _ = spanCapture;
+ {
+ spanCapture = array.span()
+ }() // expected-note{{this use causes the lifetime-dependent value to escape}}
+}
+
+// 'spanBox' escapes to 'closure' before it is captured by 'escapedSpan'. The 'inout_aliasable' capture is considered
+// escaping because the closure contains a 'begin_access [dynamic]'.
+func testNoEscapClosureCaptureHasEscaped(spanArg: Span<Int>, array: consuming [Int]) {
+ // expected-error@-1{{lifetime-dependent variable 'spanArg' escapes its scope}}
+ // expected-note@-2{{it depends on the lifetime of argument 'spanArg'}}
+ // expected-note@-3{{it depends on a closure capture; this is not yet supported}}
+ var spanBox = spanArg // expected-error{{lifetime-dependent variable 'spanBox' escapes its scope}}
+ // expected-note@-1{{it depends on a closure capture; this is not yet supported}}
+ // expected-note@-2{{this use causes the lifetime-dependent value to escape}}
+ let closure = { spanBox } // expected-note{{this use causes the lifetime-dependent value to escape}}
+
+ let escapedSpan = {
+ spanBox = array.span() // expected-error{{lifetime-dependent value escapes its scope}}
+ // expected-note@-1{{this use causes the lifetime-dependent value to escape}}
+ return closure() // expected-error{{lifetime-dependent value escapes its scope}}
+ // expected-note@-1{{it depends on the lifetime of this parent value}}
+ // expected-note@-2{{this use causes the lifetime-dependent value to escape}}
+ }()
+ _ = consume array
+ _ = escapedSpan
+}
+
 // =============================================================================
 // Scoped dependence on property access
 // =============================================================================

test/SILOptimizer/lifetime_dependence/verify_diagnostics.swift

@@ -409,3 +409,23 @@ func returnTempBorrow() -> Borrow<Int> {
 func test(inline: InlineInt) {
  inline.span.withUnsafeBytes { _ = $0 }
 }
+
+// =============================================================================
+// Closures
+// =============================================================================
+
+/// Test an autoclosure that invokes a mutable method where `Self: ~Escapable`.
+/// The @inout_aliasable argument has an implicit @_lifetime(capture: copy capture),
+/// and no begin_access [dynamic] is present in the closure.
+extension MutableSpan {
+ @_lifetime(self: copy self)
+ public mutating func canUpdate() -> Bool { return true }
+
+ @_lifetime(self: copy self)
+ public mutating func testAutoclosure(z: Bool) -> Bool {
+ if z && canUpdate() {
+ return true
+ }
+ return false
+ }
+}