Merge pull request swiftlang#76972 from tshortli/trc-expansion-request-side-effect

Author: tshortli

include/swift/AST/TypeCheckRequests.h

@@ -4852,23 +4852,22 @@ class InitAccessorReferencedVariablesRequest
 /// Expand the children of the given type refinement context.
 class ExpandChildTypeRefinementContextsRequest
     : public SimpleRequest<ExpandChildTypeRefinementContextsRequest,
-                           std::vector<TypeRefinementContext *>(
-                               TypeRefinementContext *),
+                           evaluator::SideEffect(TypeRefinementContext *),
                            RequestFlags::SeparatelyCached> {
 public:
   using SimpleRequest::SimpleRequest;
 
 private:
   friend SimpleRequest;
 
-  std::vector<TypeRefinementContext *>
-  evaluate(Evaluator &evaluator, TypeRefinementContext *parentTRC) const;
+  evaluator::SideEffect evaluate(Evaluator &evaluator,
+                                 TypeRefinementContext *parentTRC) const;
 
 public:
   // Separate caching.
   bool isCached() const { return true; }
-  std::optional<std::vector<TypeRefinementContext *>> getCachedResult() const;
-  void cacheResult(std::vector<TypeRefinementContext *> children) const;
+  std::optional<evaluator::SideEffect> getCachedResult() const;
+  void cacheResult(evaluator::SideEffect) const;
 };
 
 class SerializeAttrGenericSignatureRequest

lib/AST/TypeRefinementContext.cpp

@@ -208,20 +208,21 @@ TypeRefinementContext::findMostRefinedSubContext(SourceLoc Loc,
   if (SrcRange.isValid() && !Ctx.SourceMgr.containsTokenLoc(SrcRange, Loc))
     return nullptr;
 
-  auto expandedChildren = evaluateOrDefault(
-      Ctx.evaluator, ExpandChildTypeRefinementContextsRequest{this}, {});
+  (void)evaluateOrDefault(Ctx.evaluator,
+                          ExpandChildTypeRefinementContextsRequest{this}, {});
+  assert(!getNeedsExpansion());
 
   // Do a binary search to find the first child with a source range that
   // ends after the given location.
   auto iter = std::lower_bound(
-      expandedChildren.begin(), expandedChildren.end(), Loc,
+      Children.begin(), Children.end(), Loc,
       [&Ctx](TypeRefinementContext *context, SourceLoc loc) {
         return Ctx.SourceMgr.isBefore(context->getSourceRange().End, loc);
       });
 
   // Check whether the matching child or any of its descendants contain
   // the given location.
-  if (iter != expandedChildren.end()) {
+  if (iter != Children.end()) {
     if (auto found = (*iter)->findMostRefinedSubContext(Loc, Ctx))
       return found;
   }
@@ -478,18 +479,17 @@ void swift::simple_display(
   out << "TRC @" << trc;
 }
 
-std::optional<std::vector<TypeRefinementContext *>>
+std::optional<evaluator::SideEffect>
 ExpandChildTypeRefinementContextsRequest::getCachedResult() const {
   auto *TRC = std::get<0>(getStorage());
   if (TRC->getNeedsExpansion())
     return std::nullopt;
-  return TRC->Children;
+  return evaluator::SideEffect();
 }
 
 void ExpandChildTypeRefinementContextsRequest::cacheResult(
-    std::vector<TypeRefinementContext *> children) const {
+    evaluator::SideEffect sideEffect) const {
   auto *TRC = std::get<0>(getStorage());
-  TRC->Children = children;
   TRC->setNeedsExpansion(false);
 }
 

lib/Sema/TypeCheckAvailability.cpp

@@ -1384,8 +1384,7 @@ TypeChecker::getOrBuildTypeRefinementContext(SourceFile *SF) {
   return TRC;
 }
 
-std::vector<TypeRefinementContext *>
-ExpandChildTypeRefinementContextsRequest::evaluate(
+evaluator::SideEffect ExpandChildTypeRefinementContextsRequest::evaluate(
     Evaluator &evaluator, TypeRefinementContext *parentTRC) const {
   assert(parentTRC->getNeedsExpansion());
   if (auto decl = parentTRC->getDeclOrNull()) {
@@ -1394,7 +1393,7 @@ ExpandChildTypeRefinementContextsRequest::evaluate(
     builder.prepareDeclForLazyExpansion(decl);
     builder.build(decl);
   }
-  return parentTRC->Children;
+  return evaluator::SideEffect();
 }
 
 AvailabilityRange TypeChecker::overApproximateAvailabilityAtLocation(