[CopyPropagation] Hoist owned lexical destroys.

Author: nate-chandler

lib/SILOptimizer/Transforms/CopyPropagation.cpp

@@ -471,11 +471,17 @@ void CopyPropagation::run() {
       auto folded = foldDestroysOfCopiedLexicalBorrow(bbi, *domTree, deleter);
       if (!folded)
         break;
-      // We don't add the produced move_value instruction to the worklist
-      // because it can't handle propagation.
+      auto hoisted = hoistDestroysOfOwnedLexicalValue(folded, *f, deleter);
+      // Keep running even if the new move's destroys can't be hoisted.
+      (void)hoisted;
       firstRun = false;
     }
   }
+  for (auto *argument : f->getArguments()) {
+    if (argument->getOwnershipKind() == OwnershipKind::Owned) {
+      hoistDestroysOfOwnedLexicalValue(argument, *f, deleter);
+    }
+  }
   deleter.cleanupDeadInstructions();
 
   // For now, only modify forwarding instructions

test/Distributed/SIL/distributed_actor_default_init_sil_5.swift

@@ -64,7 +64,6 @@ distributed actor MyDistActor {
 // CHECK: [[CONTINUE]]:
 // CHECK:        hop_to_executor [[SELF]] : $MyDistActor
 // CHECK-NEXT:   retain_value [[SYSTEM]] : $FakeActorSystem
-// CHECK-NEXT:   retain_value [[SYSTEM]] : $FakeActorSystem
 // CHECK-NEXT:   // function_ref FakeActorSystem.actorReady<A>(_:)
 // CHECK-NEXT:   [[READY_FN:%[0-9]+]] = function_ref @$s27FakeDistributedActorSystems0aC6SystemV10actorReadyyyx01_B00bC0RzAA0C7AddressV2IDRtzlF : $@convention(method) <τ_0_0 where τ_0_0 : DistributedActor, τ_0_0.ID == ActorAddress> (@guaranteed τ_0_0, @guaranteed FakeActorSystem) -> ()
 // CHECK-NEXT:   = apply [[READY_FN]]

test/SILGen/moveonly_builtin.swift

@@ -31,10 +31,10 @@ class Klass {}
 // CHECK-SIL-NEXT: debug_value
 // CHECK-SIL-NEXT: strong_retain
 // CHECK-SIL-NEXT: move_value
+// CHECK-SIL-NEXT: strong_release
 // CHECK-SIL-NEXT: debug_value [moved] undef
 // CHECK-SIL-NEXT: tuple
 // CHECK-SIL-NEXT: tuple
-// CHECK-SIL-NEXT: strong_release
 // CHECK-SIL-NEXT: return
 // CHECK-SIL: } // end sil function '$s8moveonly7useMoveyAA5KlassCADnF'
 func useMove(_ k: __owned Klass) -> Klass {
@@ -65,10 +65,10 @@ func useMove(_ k: __owned Klass) -> Klass {
 // CHECK-SIL-NEXT: debug_value
 // CHECK-SIL-NEXT: strong_retain
 // CHECK-SIL-NEXT: move_value
+// CHECK-SIL-NEXT: strong_release
 // CHECK-SIL-NEXT: debug_value [moved] undef
 // CHECK-SIL-NEXT: tuple
 // CHECK-SIL-NEXT: tuple
-// CHECK-SIL-NEXT: strong_release
 // CHECK-SIL-NEXT: return
 // CHECK-SIL: } // end sil function '$s8moveonly7useMoveyxxnRlzClF'
 func useMove<T : AnyObject>(_ k: __owned T) -> T {

test/SILOptimizer/copy_propagation_borrow.sil

@@ -233,12 +233,13 @@ bb3:
 // CHECK:      bb1:
 // CHECK-NEXT:   [[COPY:%.*]] = copy_value [[OUTERCOPY]] : $C
 // CHECK-NEXT:   apply %{{.*}}([[COPY]]) : $@convention(thin) (@owned C) -> ()
+// CHECK-NEXT:   destroy_value %0 : $C
 // CHECK-NEXT:   br bb3
 // CHECK:      bb2:
+// CHECK-NEXT:   destroy_value %0 : $C
 // CHECK-NEXT:   br bb3
 // CHECK:      bb3:
 // CHECK-NEXT:   destroy_value [[OUTERCOPY]] : $C
-// CHECK-NEXT:   destroy_value %0 : $C
 // CHECK-LABEL: } // end sil function 'testLocalBorrowPostDomDestroy'
 sil [ossa] @testLocalBorrowPostDomDestroy : $@convention(thin) (@owned C) -> () {
 bb0(%0 : @owned $C):
@@ -274,13 +275,14 @@ bb3:
 // CHECK:      bb1:
 // CHECK-NEXT:   apply %{{.*}}([[OUTERCOPY]]) : $@convention(thin) (@guaranteed C) -> ()
 // CHECK-NEXT:   apply %{{.*}}([[OUTERCOPY]]) : $@convention(thin) (@owned C) -> ()
+// CHECK-NEXT:   destroy_value %0 : $C
 // CHECK-NEXT:   br bb3
 // CHECK:      bb2:
 // CHECK-NEXT:   apply %{{.*}}([[OUTERCOPY]]) : $@convention(thin) (@guaranteed C) -> ()
+// CHECK-NEXT:   destroy_value %0 : $C
 // CHECK-NEXT:   destroy_value [[OUTERCOPY]] : $C
 // CHECK-NEXT:   br bb3
 // CHECK:      bb3:
-// CHECK-NEXT:   destroy_value %0 : $C
 // CHECK-LABEL: } // end sil function 'testLocalBorrowNoPostDomDestroy'
 sil [ossa] @testLocalBorrowNoPostDomDestroy : $@convention(thin) (@owned C) -> () {
 bb0(%0 : @owned $C):
@@ -316,17 +318,18 @@ bb3:
 // CHECK-NEXT:  apply %{{.*}}([[OUTERCOPY]]) : $@convention(thin) (@guaranteed C) -> ()
 // CHECK-NEXT:  [[ARGCOPY:%.*]] = copy_value [[OUTERCOPY]] : $C
 // CHECK-NEXT:  apply %2([[OUTERCOPY]], [[ARGCOPY:%.*]]) : $@convention(thin) (@owned C, @owned C) -> ()
+// CHECK-NEXT:  destroy_value %0 : $C
 // CHECK-NEXT:  br bb3
 // CHECK:     bb2:
 // CHECK-NEXT:  apply %{{.*}}([[OUTERCOPY]]) : $@convention(thin) (@guaranteed C) -> ()
 //
 // This copy would be eliminated if the outer lifetime were also canonicalized (no unchecked_ownership_conversion)
+// CHECK-NEXT:  destroy_value %0 : $C
 // CHECK-NEXT:  [[COPY2:%.*]] = copy_value [[OUTERCOPY]] : $C
 // CHECK-NEXT:  destroy_value [[COPY2]] : $C
 // CHECK-NEXT:  destroy_value %4 : $C
 // CHECK-NEXT:  br bb3
 // CHECK: bb3:
-// CHECK-NEXT:  destroy_value %0 : $C
 // CHECK-LABEL: } // end sil function 'testLocalBorrowDoubleConsume'
 sil [ossa] @testLocalBorrowDoubleConsume : $@convention(thin) (@owned C) -> () {
 bb0(%0 : @owned $C):

test/SILOptimizer/copy_propagation_opaque.sil

@@ -440,7 +440,9 @@ bb0:
 //
 // CHECK-LABEL: sil [ossa] @testCopyBorrow : $@convention(thin) <T> (@in T) -> () {
 // CHECK:       bb0(%0 : @owned $T):
+// CHECK:       [[COPY:%[^,]+]] = copy_value %0
 // CHECK:       destroy_value %0 : $T
+// CHECK:       destroy_value [[COPY]]
 // CHECK-NEXT:  tuple
 // CHECK-NEXT:  return
 // CHECK-LABEL: } // end sil function 'testCopyBorrow'

test/SILOptimizer/shrink_borrow_scope.sil

@@ -856,13 +856,14 @@ bad(%15 : @owned $Error):
 // CHECK:       [[LEFT]]:
 // CHECK:         apply undef()
 // CHECK:         end_borrow [[LIFETIME]]
+// CHECK:         destroy_value [[INSTANCE]]
 // CHECK:         br [[EXIT:bb[0-9]+]]
 // CHECK:       [[RIGHT]]:
 // CHECK:         apply undef()
 // CHECK:         end_borrow [[LIFETIME]]
+// CHECK:         destroy_value [[INSTANCE]]
 // CHECK:         br [[EXIT]]
 // CHECK:       [[EXIT]]:
-// CHECK:         destroy_value [[INSTANCE]]
 // CHECK-LABEL: } // end sil function 'hoist_up_to_two_barrier_applies'
 sil [ossa] @hoist_up_to_two_barrier_applies : $@convention(thin) (@owned C) -> () {
 entry(%instance : @owned $C):

test/SILOptimizer/shrink_borrow_scope.swift

@@ -31,8 +31,8 @@ public func eliminate_copy_of_returned_then_consumed_owned_value(arg: __owned An
   // CHECK:       end_borrow [[ARG_LIFETIME]]
   // release result
   // release arg
-  // CHECK:       destroy_value [[RESULT]]
   // CHECK:       destroy_value [[ARG]]
+  // CHECK:       destroy_value [[RESULT]]
   // CHECK-LABEL: } // end sil function 'eliminate_copy_of_returned_then_consumed_owned_value'
 }