AST: Move parentDeclForInferredAvailability() to Decl.

NFC.

Author: tshortli

include/swift/AST/AvailabilityInference.h

@@ -31,10 +31,6 @@ class SemanticAvailableAttr;
 
 class AvailabilityInference {
 public:
-  /// Returns the decl that should be considered the parent decl of the given
-  /// decl when looking for inherited availability annotations.
-  static const Decl *parentDeclForInferredAvailability(const Decl *D);
-
   /// Infers the common availability required to access an array of
   /// declarations and adds attributes reflecting that availability
   /// to ToDecl.

include/swift/AST/Decl.h

@@ -1521,6 +1521,10 @@ class alignas(1 << DeclAlignInBits) Decl : public ASTAllocated<Decl>, public Swi
   /// compatibility mode.
   bool requiresUnavailableDeclABICompatibilityStubs() const;
 
+  /// Returns the decl that should be considered the parent decl when looking
+  /// for inherited availability annotations.
+  const Decl *parentDeclForAvailability() const;
+
   // List the SPI groups declared with @_spi or inherited by this decl.
   //
   // SPI groups are inherited from the parent contexts only if the local decl

lib/AST/Availability.cpp

@@ -197,7 +197,7 @@ void AvailabilityInference::applyInferredAvailableAttrs(
 
       // Walk up the enclosing declaration hierarchy to make sure we aren't
       // missing any inherited attributes.
-      D = AvailabilityInference::parentDeclForInferredAvailability(D);
+      D = D->parentDeclForAvailability();
     } while (D);
   }
 
@@ -213,32 +213,31 @@ void AvailabilityInference::applyInferredAvailableAttrs(
 
 /// Returns the decl that should be considered the parent decl of the given decl
 /// when looking for inherited availability annotations.
-const Decl *
-AvailabilityInference::parentDeclForInferredAvailability(const Decl *D) {
-  if (auto *AD = dyn_cast<AccessorDecl>(D))
+const Decl *Decl::parentDeclForAvailability() const {
+  if (auto *AD = dyn_cast<AccessorDecl>(this))
     return AD->getStorage();
 
-  if (auto *ED = dyn_cast<ExtensionDecl>(D)) {
+  if (auto *ED = dyn_cast<ExtensionDecl>(this)) {
     if (auto *NTD = ED->getExtendedNominal())
       return NTD;
   }
 
-  if (auto *PBD = dyn_cast<PatternBindingDecl>(D)) {
+  if (auto *PBD = dyn_cast<PatternBindingDecl>(this)) {
     if (PBD->getNumPatternEntries() < 1)
       return nullptr;
 
     return PBD->getAnchoringVarDecl(0);
   }
 
-  if (auto *OTD = dyn_cast<OpaqueTypeDecl>(D))
+  if (auto *OTD = dyn_cast<OpaqueTypeDecl>(this))
     return OTD->getNamingDecl();
 
   // Clang decls may be inaccurately parented rdar://53956555
-  if (D->hasClangNode())
+  if (hasClangNode())
     return nullptr;
 
   // Availability is inherited from the enclosing context.
-  return D->getDeclContext()->getInnermostDeclarationDeclContext();
+  return getDeclContext()->getInnermostDeclarationDeclContext();
 }
 
 /// Returns true if the introduced version in \p newAttr should be used instead
@@ -699,10 +698,8 @@ DeclRuntimeAvailability
 DeclRuntimeAvailabilityRequest::evaluate(Evaluator &evaluator,
                                          const Decl *decl) const {
   auto inherited = DeclRuntimeAvailability::PotentiallyAvailable;
-  if (auto *parent =
-          AvailabilityInference::parentDeclForInferredAvailability(decl)) {
+  if (auto *parent = decl->parentDeclForAvailability())
     inherited = getDeclRuntimeAvailability(parent);
-  }
 
   // If the inherited runtime availability is already maximally unavailable
   // then skip computing unavailability for this declaration.
@@ -788,8 +785,7 @@ Decl::getAvailableAttrForPlatformIntroduction(bool checkExtension) const {
   if (!checkExtension)
     return std::nullopt;
 
-  if (auto parent =
-          AvailabilityInference::parentDeclForInferredAvailability(this)) {
+  if (auto parent = parentDeclForAvailability()) {
     if (auto *ED = dyn_cast<ExtensionDecl>(parent)) {
       if (auto attr = getDeclAvailableAttrForPlatformIntroduction(ED))
         return attr;

lib/AST/AvailabilityConstraint.cpp

@@ -13,7 +13,6 @@
 #include "swift/AST/AvailabilityConstraint.h"
 #include "swift/AST/ASTContext.h"
 #include "swift/AST/AvailabilityContext.h"
-#include "swift/AST/AvailabilityInference.h"
 #include "swift/AST/Decl.h"
 
 using namespace swift;
@@ -319,7 +318,7 @@ swift::getAvailabilityConstraintsForDecl(const Decl *decl,
   if (decl->getClangNode())
     return constraints;
 
-  auto parent = AvailabilityInference::parentDeclForInferredAvailability(decl);
+  auto parent = decl->parentDeclForAvailability();
   if (auto extension = dyn_cast_or_null<ExtensionDecl>(parent))
     getAvailabilityConstraintsForDecl(constraints, extension, context, flags);
 

lib/AST/Decl.cpp

@@ -591,8 +591,7 @@ const Decl *Decl::getInnermostDeclWithAvailability() const {
   if (getAttrs().hasAttribute<AvailableAttr>())
     return this;
 
-  if (auto parent =
-          AvailabilityInference::parentDeclForInferredAvailability(this))
+  if (auto parent = parentDeclForAvailability())
     return parent->getInnermostDeclWithAvailability();
 
   return nullptr;
@@ -1492,7 +1491,7 @@ AvailabilityRange Decl::getAvailabilityForLinkage() const {
     return *containingContext;
   }
 
-  // FIXME: Adopt AvailabilityInference::parentDeclForInferredAvailability()
+  // FIXME: Adopt Decl::parentDeclForAvailability()
   // here instead of duplicating the logic.
   if (auto *accessor = dyn_cast<AccessorDecl>(this))
     return accessor->getStorage()->getAvailabilityForLinkage();

lib/Sema/TypeCheckAttr.cpp

@@ -2205,8 +2205,7 @@ getSemanticAvailableRangeDeclAndAttr(const Decl *decl) {
           /*checkExtension=*/false))
     return std::make_pair(*attr, decl);
 
-  if (auto *parent =
-          AvailabilityInference::parentDeclForInferredAvailability(decl))
+  if (auto *parent = decl->parentDeclForAvailability())
     return getSemanticAvailableRangeDeclAndAttr(parent);
 
   return std::nullopt;
@@ -5059,8 +5058,7 @@ void AttributeChecker::checkAvailableAttrs(ArrayRef<AvailableAttr *> attrs) {
   // Compute availability constraints for the decl, relative to its parent
   // declaration or to the deployment target.
   auto availabilityContext = AvailabilityContext::forDeploymentTarget(Ctx);
-  if (auto parent =
-          AvailabilityInference::parentDeclForInferredAvailability(D)) {
+  if (auto parent = D->parentDeclForAvailability()) {
     auto parentAvailability = AvailabilityContext::forDeclSignature(parent);
     availabilityContext.constrainWithContext(parentAvailability, Ctx);
   }
@@ -5237,8 +5235,7 @@ void AttributeChecker::checkBackDeployedAttrs(
           break;
         }
 
-        attrDecl =
-            AvailabilityInference::parentDeclForInferredAvailability(attrDecl);
+        attrDecl = attrDecl->parentDeclForAvailability();
       } while (attrDecl);
 
       continue;
@@ -5424,10 +5421,9 @@ std::optional<Diagnostic>
 TypeChecker::diagnosticIfDeclCannotBeUnavailable(const Decl *D,
                                                  SemanticAvailableAttr attr) {
   auto parentIsUnavailable = [](const Decl *D) -> bool {
-    if (auto *parent =
-            AvailabilityInference::parentDeclForInferredAvailability(D)) {
+    if (auto *parent = D->parentDeclForAvailability())
       return AvailabilityContext::forDeclSignature(parent).isUnavailable();
-    }
+
     return false;
   };