Add tests for SILGen support of @_addressable annotations.

Motivates: rdar://152280207 (@_addressable annotations should support
address projections into copyable types)

Author: atrick

test/SILOptimizer/lifetime_dependence/projections.swift

@@ -0,0 +1,192 @@
+// RUN: %target-swift-frontend %s -emit-sil \
+// RUN:   -o /dev/null \
+// RUN:   -verify \
+// RUN:   -sil-verify-all \
+// RUN:   -enable-builtin-module \
+// RUN:   -module-name test \
+// RUN:   -enable-experimental-feature Lifetimes \
+// RUN:   -enable-experimental-feature AddressableTypes \
+// RUN:   -enable-experimental-feature AddressableParameters
+
+// RUN: %target-swift-frontend %s -emit-silgen \
+// RUN:   -sil-verify-all \
+// RUN:   -enable-builtin-module \
+// RUN:   -module-name test \
+// RUN:   -enable-experimental-feature Lifetimes \
+// RUN:   -enable-experimental-feature AddressableTypes \
+// RUN:   -enable-experimental-feature AddressableParameters \
+// RUN:   2>&1 | %FileCheck %s
+
+// REQUIRES: swift_in_compiler
+// REQUIRES: swift_feature_LifetimeDependence
+
+import Builtin
+
+class C {
+  var p: Builtin.RawPointer
+  init(p: Builtin.RawPointer) { self.p = p }
+
+  // unsupported annotation
+  @_addressableSelf
+  func method() {}
+}
+
+struct NE: ~Escapable {
+  var p: Builtin.RawPointer
+}
+
+struct PtrHolder {
+  var field: Builtin.RawPointer
+}
+
+struct CHolder {
+  var field: C
+}
+
+struct IHolder {
+  var field: Int
+}
+
+@_lifetime(borrow ptr)
+func depends(onPtr ptr: Builtin.RawPointer) -> NE {
+  NE(p: ptr)
+}
+
+// FIXME: Allowed now, but should be prohibited if projection dependence carries exclusivity.
+// !!! need radar
+@_lifetime(&holder)
+func testTrivialField(holder: inout PtrHolder, other: Builtin.RawPointer) -> NE {
+  // copy holder.field
+  // end_access holder.field
+  let ne = depends(onPtr: holder.field)
+  // mark_dependence ne on holder
+  holder.field = other
+  return ne
+}
+
+@_lifetime(borrow c)
+func depends(onC c: C) -> NE {
+  let ne = NE(p: c.p)
+  return _overrideLifetime(ne, borrowing: c)
+}
+
+// OK: Correctly diagnoses the exclusivity violation.
+@_lifetime(&holder)
+func testObjectField(holder: inout CHolder, other: C) -> NE {
+  // copy holder.field
+  // end_access holder.field
+  let ne = depends(onC: holder.field) // expected-note{{conflicting access is here}}
+  // mark_dependence ne on holder
+  holder.field = other // expected-error{{overlapping accesses to 'holder.field', but modification requires exclusive access; consider copying to a local variable}}
+  return ne
+}
+
+// OK
+@_lifetime(&holder)
+func testAddress(holder: inout IHolder) -> NE {
+  // Requires rdar://137608270 ([borrows] Add Builtin.addressof() support for @addressable arguments)
+  depends(onPtr: Builtin.addressOfBorrow(holder))
+}
+
+@_lifetime(borrow i)
+func depends(onInt i: @_addressable Int) -> NE {
+  NE(p: Builtin.addressOfBorrow(i))
+}
+
+// OK: no escape diagnostic because the addressable dependency is on the parameter address.
+@_lifetime(&holder)
+func testAddressableTrivialField(holder: inout IHolder) -> NE{
+  // load holder.field
+  // end_access holder.field
+  // alloc_stack Int
+  // store
+  return depends(onInt: holder.field)
+  // mark_dependence on alloc_stack
+  // (the addressable dependence needs to be on the passed-in address)
+}
+
+@_lifetime(borrow x)
+func depends(onCAddress x: @_addressable C) -> NE {
+  let ne = NE(p: x.p)
+  return _overrideLifetime(ne, borrowing: x)
+}
+
+// OK: no escape diagnostic because the addressable dependency is on the parameter address.
+@_lifetime(&holder)
+func testAddressableObjectField(holder: inout CHolder) -> NE {
+  // tmp = load [copy] holder.field
+  // end_access holder.field
+  // alloc_stack
+  // store tmp
+  return depends(onCAddress: holder.field)
+  // mark_dependence ne on alloc_stack
+}
+
+// Copyable to test the absence of temporaries.
+@_addressableForDependencies
+struct Cell<T> {
+  var t: T
+}
+
+struct CellHolder: ~Copyable {
+  var field: Cell<Int>
+}
+
+@_lifetime(borrow x)
+func depends(onCell x: borrowing Cell<Int>) -> NE {
+  NE(p: Builtin.addressOfBorrow(x))
+}
+
+// OK: no escape diagnostic because the addressable dependency is on the parameter address.
+@_lifetime(&holder)
+func testAddressableType(holder: inout CellHolder) -> NE {
+  // tmp = load [copy] holder.field
+  // end_access holder.field
+  // alloc_stack
+  // store tmp
+  return depends(onCell: holder.field)
+  // mark_dependence ne on alloc_stack
+}
+
+/* FIXME: Invalid SIL: rdar://152273896 (SILGen: @_addressableSelf support for class methods)
+func testAddressableClass(c: C) {
+  c.method()
+}
+*/
+
+struct Object {
+  var c: C
+
+  @_addressableSelf
+  func method() {}
+}
+
+struct UniquePointer<T>: ~Copyable {
+  var _p: UnsafePointer<T>
+
+  var value: T { unsafeAddress { _p } }
+}
+
+// No copy allowed. A copy would be invalid when class 'C' is imported from C++.
+//
+// CHECK-LABEL: sil hidden [ossa] @$s4test0A15AddressableSelf2upyAA13UniquePointerVyAA6ObjectVG_tF : $@convention(thin) (@guaranteed UniquePointer<Object>) -> () {
+// CHECK: bb0(%0 : @guaranteed $UniquePointer<Object>):
+// CHECK:   [[CP:%[0-9]+]] = copy_value %0
+// CHECK:   [[MNC:%[0-9]+]] = mark_unresolved_non_copyable_value [no_consume_or_assign] [[CP]]
+// CHECK:   [[BB:%[0-9]+]] = begin_borrow [[MNC]]
+// CHECK:   [[PTR:%[0-9]+]] = struct_extract %{{.*}}, #UnsafePointer._rawValue
+// CHECK:   [[ADR:%[0-9]+]] = pointer_to_address [[PTR]] to [strict] $*Object
+// CHECK:   [[MD:%[0-9]+]] = mark_dependence [unresolved] [[ADR]] on [[BB]]
+// CHECK-NOT: load
+// CHECK-NOT: alloc_stack
+// CHECK-NOT: store
+// CHECK:   apply %{{.*}}([[MD]]) : $@convention(method) (@in_guaranteed Object) -> ()
+// CHECK-LABEL: } // end sil function '$s4test0A15AddressableSelf2upyAA13UniquePointerVyAA6ObjectVG_tF'
+func testAddressableSelf(up: borrowing UniquePointer<Object>) {
+  // tmp = load [copy] up.value
+  // end_access up.value
+  // alloc_stack
+  // store tmp
+  // apply method(tmp)
+  up.value.method()
+}