[silgen] Update SILGen objc deallocators and enable ownership on objc_dealloc.swift

rdar://33358110

Author: gottesmm

lib/SILGen/SILGenBuilder.cpp

@@ -192,12 +192,21 @@ AllocExistentialBoxInst *SILGenBuilder::createAllocExistentialBox(
 ManagedValue SILGenBuilder::createStructExtract(SILLocation loc,
                                                 ManagedValue base,
                                                 VarDecl *decl) {
-  ManagedValue borrowedBase = SGF.emitManagedBeginBorrow(loc, base.getValue());
+  ManagedValue borrowedBase = base.borrow(SGF, loc);
   SILValue extract =
       SILBuilder::createStructExtract(loc, borrowedBase.getValue(), decl);
   return ManagedValue::forUnmanaged(extract);
 }
 
+ManagedValue SILGenBuilder::createRefElementAddr(SILLocation loc,
+                                                 ManagedValue operand,
+                                                 VarDecl *field,
+                                                 SILType resultTy) {
+  operand = operand.borrow(SGF, loc);
+  SILValue result = createRefElementAddr(loc, operand.getValue(), field);
+  return ManagedValue::forUnmanaged(result);
+}
+
 ManagedValue SILGenBuilder::createCopyValue(SILLocation loc,
                                             ManagedValue originalValue) {
   auto &lowering = SGF.getTypeLowering(originalValue.getType());

lib/SILGen/SILGenBuilder.h

@@ -134,11 +134,16 @@ class SILGenBuilder : public SILBuilder {
   //
 
   using SILBuilder::createStructExtract;
-  using SILBuilder::createCopyValue;
-  using SILBuilder::createCopyUnownedValue;
   ManagedValue createStructExtract(SILLocation loc, ManagedValue base,
                                    VarDecl *decl);
 
+  using SILBuilder::createRefElementAddr;
+  ManagedValue createRefElementAddr(SILLocation loc, ManagedValue operand,
+                                    VarDecl *field, SILType resultTy);
+
+  using SILBuilder::createCopyValue;
+  using SILBuilder::createCopyUnownedValue;
+
   /// Emit a +1 copy on \p originalValue that lives until the end of the current
   /// lexical scope.
   ManagedValue createCopyValue(SILLocation loc, ManagedValue originalValue);

lib/SILGen/SILGenDestructor.cpp

@@ -78,10 +78,10 @@ void SILGenFunction::emitDestroyingDestructor(DestructorDecl *dd) {
 
   {
     Scope S(Cleanups, cleanupLoc);
-    ManagedValue borrowedResultSelfValue =
-        emitManagedBeginBorrow(cleanupLoc, resultSelfValue);
-    SILValue borrowedValue = borrowedResultSelfValue.getUnmanagedValue();
-    if (classTy != borrowedValue->getType()) {
+    ManagedValue borrowedValue =
+        ManagedValue::forUnmanaged(resultSelfValue).borrow(*this, cleanupLoc);
+
+    if (classTy != borrowedValue.getType()) {
       borrowedValue =
           B.createUncheckedRefCast(cleanupLoc, borrowedValue, classTy);
     }
@@ -168,23 +168,30 @@ void SILGenFunction::emitIVarDestroyer(SILDeclRef ivarDestroyer) {
   RegularLocation loc(cd);
   loc.markAutoGenerated();
 
-  SILValue selfValue = emitSelfDecl(cd->getDestructor()->getImplicitSelfDecl());
+  ManagedValue selfValue = ManagedValue::forUnmanaged(
+      emitSelfDecl(cd->getDestructor()->getImplicitSelfDecl()));
 
   auto cleanupLoc = CleanupLocation::get(loc);
   prepareEpilog(TupleType::getEmpty(getASTContext()), false, cleanupLoc);
-  emitClassMemberDestruction(selfValue, cd, cleanupLoc);
+  {
+    Scope S(*this, cleanupLoc);
+    emitClassMemberDestruction(selfValue, cd, cleanupLoc);
+  }
+
   B.createReturn(loc, emitEmptyTuple(loc));
   emitEpilog(loc);
 }
 
-void SILGenFunction::emitClassMemberDestruction(SILValue selfValue,
+void SILGenFunction::emitClassMemberDestruction(ManagedValue selfValue,
                                                 ClassDecl *cd,
                                                 CleanupLocation cleanupLoc) {
+  selfValue = selfValue.borrow(*this, cleanupLoc);
   for (VarDecl *vd : cd->getStoredProperties()) {
     const TypeLowering &ti = getTypeLowering(vd->getType());
     if (!ti.isTrivial()) {
-      SILValue addr = B.createRefElementAddr(cleanupLoc, selfValue, vd,
-                                         ti.getLoweredType().getAddressType());
+      SILValue addr =
+          B.createRefElementAddr(cleanupLoc, selfValue.getValue(), vd,
+                                 ti.getLoweredType().getAddressType());
       B.createDestroyAddr(cleanupLoc, addr);
     }
   }

lib/SILGen/SILGenFunction.h

@@ -500,8 +500,9 @@ class LLVM_LIBRARY_VISIBILITY SILGenFunction
   ///
   /// \param selfValue The 'self' value.
   /// \param cd The class declaration whose members are being destroyed.
-  void emitClassMemberDestruction(SILValue selfValue, ClassDecl *cd,
+  void emitClassMemberDestruction(ManagedValue selfValue, ClassDecl *cd,
                                   CleanupLocation cleanupLoc);
+
   /// Generates code for a curry thunk from one uncurry level
   /// of a function to another.
   void emitCurryThunk(SILDeclRef thunk);

test/SILGen/objc_dealloc.swift

@@ -1,4 +1,4 @@
-// RUN: %target-swift-frontend -sdk %S/Inputs -I %S/Inputs -enable-source-import %s -emit-silgen | %FileCheck %s
+// RUN: %target-swift-frontend -sdk %S/Inputs -I %S/Inputs -enable-source-import %s -emit-silgen -enable-sil-ownership | %FileCheck %s
 
 // REQUIRES: objc_interop
 
@@ -18,7 +18,7 @@ class SwiftGizmo : Gizmo {
   // CHECK-NEXT: return [[RESULT]] : $X
 
   // CHECK-LABEL: sil hidden @_T012objc_dealloc10SwiftGizmoC{{[_0-9a-zA-Z]*}}fc
-  // CHECK: bb0([[SELF_PARAM:%[0-9]+]] : $SwiftGizmo):
+  // CHECK: bb0([[SELF_PARAM:%[0-9]+]] : @owned $SwiftGizmo):
   override init() {
     // CHECK:   [[SELF_BOX:%.*]] = alloc_box ${ var SwiftGizmo }, let, name "self"
     // CHECK:   [[SELF_UNINIT:%.*]] = mark_uninitialized [derivedselfonly] [[SELF_BOX]] : ${ var SwiftGizmo }
@@ -36,7 +36,7 @@ class SwiftGizmo : Gizmo {
 
   // CHECK-LABEL: sil hidden @_T012objc_dealloc10SwiftGizmoCfD : $@convention(method) (@owned SwiftGizmo) -> ()
   deinit {
-    // CHECK: bb0([[SELF:%[0-9]+]] : $SwiftGizmo):
+    // CHECK: bb0([[SELF:%[0-9]+]] : @owned $SwiftGizmo):
     // Call onDestruct()
     // CHECK:   [[ONDESTRUCT_REF:%[0-9]+]] = function_ref @_T012objc_dealloc10onDestructyyF : $@convention(thin) () -> ()
     // CHECK:   [[ONDESTRUCT_RESULT:%[0-9]+]] = apply [[ONDESTRUCT_REF]]() : $@convention(thin) () -> ()
@@ -56,7 +56,7 @@ class SwiftGizmo : Gizmo {
 
   // Objective-C deallocation deinit thunk (i.e., -dealloc).
   // CHECK-LABEL: sil hidden [thunk] @_T012objc_dealloc10SwiftGizmoCfDTo : $@convention(objc_method) (SwiftGizmo) -> ()
-  // CHECK: bb0([[SELF:%[0-9]+]] : $SwiftGizmo):
+  // CHECK: bb0([[SELF:%[0-9]+]] : @unowned $SwiftGizmo):
   // CHECK:   [[SELF_COPY:%.*]] = copy_value [[SELF]]
 
   // CHECK:   [[GIZMO_DTOR:%[0-9]+]] = function_ref @_T012objc_dealloc10SwiftGizmoCfD : $@convention(method) (@owned SwiftGizmo) -> ()
@@ -65,7 +65,7 @@ class SwiftGizmo : Gizmo {
 
   // Objective-C IVar initializer (i.e., -.cxx_construct)
   // CHECK-LABEL: sil hidden @_T012objc_dealloc10SwiftGizmoCfeTo : $@convention(objc_method) (@owned SwiftGizmo) -> @owned SwiftGizmo
-  // CHECK: bb0([[SELF_PARAM:%[0-9]+]] : $SwiftGizmo):
+  // CHECK: bb0([[SELF_PARAM:%[0-9]+]] : @owned $SwiftGizmo):
   // CHECK-NEXT:   debug_value [[SELF_PARAM]] : $SwiftGizmo, let, name "self"
   // CHECK-NEXT:   [[SELF:%[0-9]+]] = mark_uninitialized [rootself] [[SELF_PARAM]] : $SwiftGizmo
   // CHECK:        [[XINIT:%[0-9]+]] = function_ref @_T012objc_dealloc10SwiftGizmoC1xAA1XCvfi
@@ -80,10 +80,12 @@ class SwiftGizmo : Gizmo {
 
   // Objective-C IVar destroyer (i.e., -.cxx_destruct)
   // CHECK-LABEL: sil hidden @_T012objc_dealloc10SwiftGizmoCfETo : $@convention(objc_method) (SwiftGizmo) -> ()
-  // CHECK:      bb0([[SELF:%[0-9]+]] : $SwiftGizmo):
-  // CHECK-NEXT:  debug_value [[SELF]] : $SwiftGizmo, let, name "self"
-  // CHECK-NEXT: [[X:%[0-9]+]] = ref_element_addr [[SELF]] : $SwiftGizmo, #SwiftGizmo.x
+  // CHECK:      bb0([[SELF:%[0-9]+]] : @unowned $SwiftGizmo):
+  // CHECK-NEXT: debug_value [[SELF]] : $SwiftGizmo, let, name "self"
+  // CHECK-NEXT: [[SELF_BORROW:%.*]] = begin_borrow [[SELF]]
+  // CHECK-NEXT: [[X:%[0-9]+]] = ref_element_addr [[SELF_BORROW]] : $SwiftGizmo, #SwiftGizmo.x
   // CHECK-NEXT: destroy_addr [[X]] : $*X
+  // CHECK-NEXT: end_borrow [[SELF_BORROW]] from [[SELF]]
   // CHECK-NEXT: [[RESULT:%[0-9]+]] = tuple ()
   // CHECK-NEXT: return [[RESULT]] : $()
 }