Fix DefiniteInitialization to handle access markers in a few more places.

Author: atrick

lib/SILOptimizer/Mandatory/DIMemoryUseCollectorOwnership.cpp

@@ -1112,7 +1112,9 @@ void ElementUseCollector::collectClassSelfUses() {
   //   4) Potential escapes after super.init, if self is closed over.
   //
   // Handle each of these in turn.
-  for (auto *Op : MUI->getUses()) {
+  SmallVector<Operand *, 8> Uses(MUI->getUses());
+  while (!Uses.empty()) {
+    Operand *Op = Uses.pop_back_val();
     SILInstruction *User = Op->getUser();
 
     // Stores to self.
@@ -1150,6 +1152,14 @@ void ElementUseCollector::collectClassSelfUses() {
     if (isa<EndBorrowInst>(User))
       continue;
 
+    // Recurse through begin_access.
+    if (auto *beginAccess = dyn_cast<BeginAccessInst>(User)) {
+      Uses.append(beginAccess->getUses().begin(), beginAccess->getUses().end());
+      continue;
+    }
+    if (isa<EndAccessInst>(User))
+      continue;
+
     // Loads of the box produce self, so collect uses from them.
     if (isa<LoadInst>(User) || isa<LoadBorrowInst>(User)) {
       auto load = cast<SingleValueInstruction>(User);
@@ -1379,8 +1389,8 @@ void ElementUseCollector::collectClassSelfUses(
       continue;
     }
 
-    // Skip end_borrow.
-    if (isa<EndBorrowInst>(User))
+    // Skip end_borrow and end_access.
+    if (isa<EndBorrowInst>(User) || isa<EndAccessInst>(User))
       continue;
 
     // ref_element_addr P, #field lookups up a field.
@@ -1417,10 +1427,9 @@ void ElementUseCollector::collectClassSelfUses(
 
     // Look through begin_borrow, upcast, unchecked_ref_cast
     // and copy_value.
-    if (isa<BeginBorrowInst>(User) ||
-        isa<UpcastInst>(User) ||
-        isa<UncheckedRefCastInst>(User) ||
-        isa<CopyValueInst>(User)) {
+    if (isa<BeginBorrowInst>(User) || isa<BeginAccessInst>(User)
+        || isa<UpcastInst>(User) || isa<UncheckedRefCastInst>(User)
+        || isa<CopyValueInst>(User)) {
       auto value = cast<SingleValueInstruction>(User);
       std::copy(value->use_begin(), value->use_end(),
                 std::back_inserter(Worklist));
@@ -1498,14 +1507,24 @@ void DelegatingInitElementUseCollector::collectClassInitSelfUses() {
   //   4) Potential escapes after super.init, if self is closed over.
   // Handle each of these in turn.
   //
-  for (auto *Op : MUI->getUses()) {
+  SmallVector<Operand *, 8> Uses(MUI->getUses());
+  while (!Uses.empty()) {
+    Operand *Op = Uses.pop_back_val();
     SILInstruction *User = Op->getUser();
 
     // Ignore end_borrow. If we see an end_borrow it can only come from a
     // load_borrow from ourselves.
     if (isa<EndBorrowInst>(User))
       continue;
 
+    // Recurse through begin_access.
+    if (auto *beginAccess = dyn_cast<BeginAccessInst>(User)) {
+      Uses.append(beginAccess->getUses().begin(), beginAccess->getUses().end());
+      continue;
+    }
+    if (isa<EndAccessInst>(User))
+      continue;
+
     // Stores to self.
     if (auto *SI = dyn_cast<StoreInst>(User)) {
       if (Op->getOperandNumber() == 1) {