[region-isolation] Add support for explicit_copy_value as a look through instruction.

Author: gottesmm

lib/SILOptimizer/Mandatory/TransferNonSendable.cpp

@@ -199,6 +199,10 @@ static SILValue getUnderlyingTrackedObjectValue(SILValue value) {
 
     temp = getUnderlyingObject(temp);
 
+    if (auto *cvi = dyn_cast<ExplicitCopyValueInst>(temp)) {
+      temp = cvi->getOperand();
+    }
+
     if (auto *dsi = dyn_cast_or_null<DestructureStructInst>(
             temp->getDefiningInstruction())) {
       temp = dsi->getOperand();
@@ -2312,6 +2316,7 @@ CONSTANT_TRANSLATION(BeginDeallocRefInst, LookThrough)
 CONSTANT_TRANSLATION(RefToBridgeObjectInst, LookThrough)
 CONSTANT_TRANSLATION(BridgeObjectToRefInst, LookThrough)
 CONSTANT_TRANSLATION(CopyValueInst, LookThrough)
+CONSTANT_TRANSLATION(ExplicitCopyValueInst, LookThrough)
 CONSTANT_TRANSLATION(EndCOWMutationInst, LookThrough)
 CONSTANT_TRANSLATION(ProjectBoxInst, LookThrough)
 CONSTANT_TRANSLATION(EndInitLetRefInst, LookThrough)
@@ -2385,7 +2390,6 @@ CONSTANT_TRANSLATION(ObjCMetatypeToObjectInst, Unhandled)
 CONSTANT_TRANSLATION(ObjCExistentialMetatypeToObjectInst, Unhandled)
 CONSTANT_TRANSLATION(ClassifyBridgeObjectInst, Unhandled)
 CONSTANT_TRANSLATION(ValueToBridgeObjectInst, Unhandled)
-CONSTANT_TRANSLATION(ExplicitCopyValueInst, Unhandled)
 CONSTANT_TRANSLATION(UnownedCopyValueInst, Unhandled)
 CONSTANT_TRANSLATION(WeakCopyValueInst, Unhandled)
 CONSTANT_TRANSLATION(StrongCopyWeakValueInst, Unhandled)

test/Concurrency/sendnonsendable_basic.sil

@@ -88,3 +88,20 @@ bb3:
   %9999 = tuple ()
   return %9999 : $()
 }
+
+sil [ossa] @explicit_copy_value_test : $@convention(thin) @async () -> () {
+bb0:
+  %0 = function_ref @constructKlass : $@convention(thin) () -> @owned NonSendableKlass
+  %1 = apply %0() : $@convention(thin) () -> @owned NonSendableKlass
+  %2 = function_ref @transferKlass : $@convention(thin) @async (@guaranteed NonSendableKlass) -> ()
+  %1a = explicit_copy_value %1 : $NonSendableKlass
+  apply [caller_isolation=nonisolated] [callee_isolation=global_actor] %2(%1a) : $@convention(thin) @async (@guaranteed NonSendableKlass) -> ()
+  // expected-warning @-1 {{passing argument of non-sendable type 'NonSendableKlass' from nonisolated context to global actor '<null>'-isolated context at this call site could yield a race with accesses later in this function}}
+  %3 = function_ref @useKlass : $@convention(thin) (@guaranteed NonSendableKlass) -> ()
+  apply %3(%1) : $@convention(thin) (@guaranteed NonSendableKlass) -> ()
+  // expected-note @-1 {{access here could race}}
+  destroy_value %1a : $NonSendableKlass
+  destroy_value %1 : $NonSendableKlass
+  %9999 = tuple ()
+  return %9999 : $()
+}