Remove DeclValidationRAII

The last real client was precedence group validation.

Author: CodaFi

include/swift/AST/Decl.h

@@ -285,7 +285,7 @@ class alignas(1 << DeclAlignInBits) Decl {
 protected:
   union { uint64_t OpaqueBits;
 
-  SWIFT_INLINE_BITFIELD_BASE(Decl, bitmax(NumDeclKindBits,8)+1+1+1+1+2+1,
+  SWIFT_INLINE_BITFIELD_BASE(Decl, bitmax(NumDeclKindBits,8)+1+1+1+1+1,
     Kind : bitmax(NumDeclKindBits,8),
 
     /// Whether this declaration is invalid.

lib/AST/Decl.cpp

@@ -2783,8 +2783,13 @@ bool ValueDecl::hasInterfaceType() const {
   return !TypeAndAccess.getPointer().isNull();
 }
 
+static bool isComputingInterfaceType(const ValueDecl *VD) {
+  return VD->getASTContext().evaluator.hasActiveRequest(
+            InterfaceTypeRequest{const_cast<ValueDecl *>(VD)});
+}
+
 bool ValueDecl::isRecursiveValidation() const {
-  if (hasValidationStarted() && !hasInterfaceType())
+  if (isComputingInterfaceType(this) && !hasInterfaceType())
     return true;
 
   if (auto *vd = dyn_cast<VarDecl>(this))

lib/Sema/TypeCheckDecl.cpp

@@ -4242,7 +4242,6 @@ InterfaceTypeRequest::evaluate(Evaluator &eval, ValueDecl *D) const {
   case DeclKind::Constructor:
   case DeclKind::Destructor: {
     auto *AFD = cast<AbstractFunctionDecl>(D);
-    DeclValidationRAII IBV(AFD);
 
     auto sig = AFD->getGenericSignature();
     bool hasSelf = AFD->hasImplicitSelfDecl();
@@ -4295,7 +4294,6 @@ InterfaceTypeRequest::evaluate(Evaluator &eval, ValueDecl *D) const {
 
   case DeclKind::Subscript: {
     auto *SD = cast<SubscriptDecl>(D);
-    DeclValidationRAII IBV(SD);
 
     auto elementTy = SD->getElementInterfaceType();
 
@@ -4313,7 +4311,6 @@ InterfaceTypeRequest::evaluate(Evaluator &eval, ValueDecl *D) const {
 
   case DeclKind::EnumElement: {
     auto *EED = cast<EnumElementDecl>(D);
-    DeclValidationRAII IBV(EED);
 
     auto *ED = EED->getParentEnum();