[region-isolation] Add support for weak_copy_value.

Author: gottesmm

lib/SILOptimizer/Analysis/RegionAnalysis.cpp

@@ -223,6 +223,7 @@ static bool isStaticallyLookThroughInst(SILInstruction *inst) {
   case SILInstructionKind::UnownedToRefInst:
   case SILInstructionKind::UpcastInst:
   case SILInstructionKind::ValueToBridgeObjectInst:
+  case SILInstructionKind::WeakCopyValueInst:
     return true;
   case SILInstructionKind::UnconditionalCheckedCastInst: {
     auto cast = SILDynamicCastInst::getAs(inst);
@@ -2342,6 +2343,7 @@ CONSTANT_TRANSLATION(DropDeinitInst, LookThrough)
 CONSTANT_TRANSLATION(ValueToBridgeObjectInst, LookThrough)
 CONSTANT_TRANSLATION(BeginCOWMutationInst, LookThrough)
 CONSTANT_TRANSLATION(OpenExistentialValueInst, LookThrough)
+CONSTANT_TRANSLATION(WeakCopyValueInst, LookThrough)
 
 //===---
 // Store
@@ -2473,7 +2475,6 @@ CONSTANT_TRANSLATION(DeallocExistentialBoxInst, Ignored)
 // Unhandled Instructions
 //
 
-CONSTANT_TRANSLATION(WeakCopyValueInst, Unhandled)
 CONSTANT_TRANSLATION(StrongCopyWeakValueInst, Unhandled)
 CONSTANT_TRANSLATION(StrongCopyUnmanagedValueInst, Unhandled)
 CONSTANT_TRANSLATION(InitExistentialValueInst, Unhandled)

test/Concurrency/transfernonsendable_instruction_matching_opaquevalues.sil

@@ -56,6 +56,16 @@ protocol P {
   func doSomething()
 }
 
+sil @initP : $@convention(thin) () -> @owned P
+sil @transferP : $@async @convention(thin) (@guaranteed P) -> ()
+
+protocol PAnyObject : AnyObject {}
+
+sil @initPAnyObject : $@convention(thin) () -> @owned PAnyObject
+sil @initPAnyObjectOptional : $@convention(thin) () -> @owned Optional<PAnyObject>
+sil @transferPAnyObject : $@async @convention(thin) (@guaranteed PAnyObject) -> ()
+sil @usePAnyObjectWeak : $@convention(thin) (@guaranteed @sil_weak Optional<PAnyObject>) -> ()
+
 /////////////////
 // MARK: Tests //
 /////////////////
@@ -97,9 +107,6 @@ bb0:
   return %9999 : $()
 }
 
-sil @initP : $@convention(thin) () -> @owned P
-sil @transferP : $@async @convention(thin) (@guaranteed P) -> ()
-
 sil [ossa] @open_existential_value_test : $@async @convention(thin) () -> () {
 bb0:
   %f = function_ref @initP : $@convention(thin) () -> @owned P
@@ -118,3 +125,25 @@ bb0:
   %9999 = tuple ()
   return %9999 : $()
 }
+
+sil [ossa] @weak_copy_value_test : $@async @convention(thin) () -> () {
+bb0:
+  %f = function_ref @initPAnyObjectOptional : $@convention(thin) () -> @owned Optional<PAnyObject>
+  %p = apply %f() : $@convention(thin) () -> @owned Optional<PAnyObject>
+
+  %pBorrowed = begin_borrow %p : $Optional<PAnyObject>
+  %pExt = unchecked_enum_data %pBorrowed : $Optional<PAnyObject>, #Optional.some!enumelt
+  %transferP = function_ref @transferPAnyObject : $@async @convention(thin) (@guaranteed PAnyObject) -> ()
+  apply [caller_isolation=nonisolated] [callee_isolation=global_actor] %transferP(%pExt) : $@async @convention(thin) (@guaranteed PAnyObject) -> () // expected-warning {{transferring value of non-Sendable type 'any PAnyObject' from nonisolated context to global actor '<null>'-isolated context}}
+
+  %w = weak_copy_value %pBorrowed : $Optional<PAnyObject>
+  %weakFunc = function_ref @usePAnyObjectWeak : $@convention(thin) (@guaranteed @sil_weak Optional<PAnyObject>) -> ()
+  apply %weakFunc(%w) : $@convention(thin) (@guaranteed @sil_weak Optional<PAnyObject>) -> () // expected-note {{access here could race}}
+  destroy_value %w : $@sil_weak Optional<PAnyObject>
+
+  end_borrow %pBorrowed : $Optional<PAnyObject>
+  destroy_value %p : $Optional<PAnyObject>
+
+  %9999 = tuple ()
+  return %9999 : $()
+}