AST: Remove VarDecl::getOpenedElementEnvironment()

Author: slavapestov

include/swift/AST/Decl.h

@@ -6053,10 +6053,6 @@ enum class PropertyWrapperSynthesizedPropertyKind {
 class VarDecl : public AbstractStorageDecl {
   friend class NamingPatternRequest;
   NamedPattern *NamingPattern = nullptr;
-  /// When the variable is declared in context of a for-in loop over the elements of 
-  /// a parameter pack, this is the opened element environment of the pack expansion
-  /// to use as the variable's context generic environment.
-  GenericEnvironment *OpenedElementEnvironment = nullptr;
 
 public:
   enum class Introducer : uint8_t {
@@ -6195,13 +6191,6 @@ class VarDecl : public AbstractStorageDecl {
   NamedPattern *getNamingPattern() const;
   void setNamingPattern(NamedPattern *Pat);
 
-  GenericEnvironment *getOpenedElementEnvironment() const {
-    return OpenedElementEnvironment;
-  }
-  void setOpenedElementEnvironment(GenericEnvironment *Env) {
-    OpenedElementEnvironment = Env;
-  }
-
   /// If this is a VarDecl that does not belong to a CaseLabelItem's pattern,
   /// return this. Otherwise, this VarDecl must belong to a CaseStmt's
   /// CaseLabelItem. In that case, return the first case label item of the first

lib/AST/Decl.cpp

@@ -7286,12 +7286,6 @@ VarDecl::VarDecl(DeclKind kind, bool isStatic, VarDecl::Introducer introducer,
 }
 
 Type VarDecl::getTypeInContext() const {
-  // If the variable is declared in context of a for-in loop over the elements
-  // of a parameter pack, its interface type must be mapped into context using
-  // the opened element environment of the pack expansion.
-  if (auto *env = getOpenedElementEnvironment())
-    return GenericEnvironment::mapTypeIntoContext(env, getInterfaceType());
-
   return getDeclContext()->mapTypeIntoContext(getInterfaceType());
 }
 

lib/AST/GenericEnvironment.cpp

@@ -416,15 +416,12 @@ Type GenericEnvironment::mapTypeIntoContext(GenericEnvironment *env,
 }
 
 Type MapTypeOutOfContext::operator()(SubstitutableType *type) const {
-  auto archetype = cast<ArchetypeType>(type);
-  if (isa<OpaqueTypeArchetypeType>(archetype->getRoot()))
-    return Type();
-
-  // Leave opened archetypes alone; they're handled contextually.
-  if (isa<OpenedArchetypeType>(archetype))
-    return Type(type);
+  if (isa<PrimaryArchetypeType>(type) ||
+      isa<PackArchetypeType>(type)) {
+    return cast<ArchetypeType>(type)->getInterfaceType();
+  }
 
-  return archetype->getInterfaceType();
+  return type;
 }
 
 Type TypeBase::mapTypeOutOfContext() {

lib/Sema/CSApply.cpp

@@ -9411,35 +9411,6 @@ static std::optional<PackIterationInfo> applySolutionToForEachStmt(
         std::optional<SyntacticElementTarget>(SyntacticElementTarget)>
         rewriteTarget) {
 
-  // A special walker to record opened element environment for var decls in a
-  // for-each loop.
-  class Walker : public ASTWalker {
-    GenericEnvironment *Environment;
-
-  public:
-    Walker(GenericEnvironment *Environment) { this->Environment = Environment; }
-
-    PreWalkResult<Stmt *> walkToStmtPre(Stmt *S) override {
-      if (isa<ForEachStmt>(S)) {
-        return Action::SkipNode(S);
-      }
-      return Action::Continue(S);
-    }
-
-    PreWalkAction walkToDeclPre(Decl *D) override {
-      if (auto *decl = dyn_cast<VarDecl>(D)) {
-        decl->setOpenedElementEnvironment(Environment);
-      }
-      if (isa<AbstractFunctionDecl>(D)) {
-        return Action::SkipNode();
-      }
-      if (isa<NominalTypeDecl>(D)) {
-        return Action::SkipNode();
-      }
-      return Action::Continue();
-    }
-  };
-
   auto &cs = solution.getConstraintSystem();
   auto *sequenceExpr = stmt->getParsedSequence();
   PackExpansionExpr *expansion = cast<PackExpansionExpr>(sequenceExpr);
@@ -9453,11 +9424,6 @@ static std::optional<PackIterationInfo> applySolutionToForEachStmt(
   // Simplify the pattern type of the pack expansion.
   info.patternType = solution.simplifyType(info.patternType);
 
-  // Record the opened element environment for the VarDecls inside the loop
-  Walker forEachWalker(expansion->getGenericEnvironment());
-  stmt->getPattern()->walk(forEachWalker);
-  stmt->getBody()->walk(forEachWalker);
-
   return info;
 }