[DestroyAddrHoisting] Don't destructure NC aggs.

When hoisting destroys of aggregates, an attempt is made to fold the
destroys of individual fields into the foregoing instructions.  If the
aggregate is noncopyable, this transformation is illegal.

Author: nate-chandler

lib/SIL/Utils/MemAccessUtils.cpp

@@ -1461,7 +1461,8 @@ bool swift::visitProductLeafAccessPathNodes(
         visitor(AccessPath::PathNode(node), silType);
         continue;
       }
-      if (decl->isCxxNonTrivial() || !silType.isEscapable(function)) {
+      if (decl->isCxxNonTrivial() || !silType.isEscapable(function) ||
+          silType.isMoveOnly()) {
         visitor(AccessPath::PathNode(node), silType);
         continue;
       }

test/SILOptimizer/hoist_destroy_addr.sil

@@ -1255,3 +1255,28 @@ bb0(%aggregate : $*NEAggregate):
   %retval = tuple ()
   return %retval
 }
+
+struct NCGutless: ~Copyable {
+  let ptr: UnsafeRawPointer?
+}
+struct NCAggregate: ~Copyable {
+  var ne: NCGutless
+  let regular: Regular
+  deinit {}
+}
+
+// CHECK-LABEL: sil [ossa] @no_destructure_noncopyable : {{.*}} {
+// CHECK:       bb0([[AGGREGATE:%[^,]+]] :
+// CHECK:       destroy_addr [[AGGREGATE]]
+// CHECK-LABEL: } // end sil function 'no_destructure_noncopyable'
+sil [ossa] @no_destructure_noncopyable : $@convention(method) (@in NCAggregate) -> () {
+bb0(%aggregate : $*NCAggregate):
+  %regular = struct_element_addr %aggregate, #NCAggregate.regular
+  %regular_copy = alloc_stack $Regular
+  copy_addr %regular to [init] %regular_copy
+  destroy_addr %regular_copy
+  dealloc_stack %regular_copy
+  destroy_addr %aggregate
+  %retval = tuple ()
+  return %retval
+}