AST: Remove unnecessary ASTContext argument.

There's no need to take one as input to a method on `Decl`. NFC.

Author: tshortli

include/swift/AST/Decl.h

@@ -1134,8 +1134,7 @@ class alignas(1 << DeclAlignInBits) Decl : public ASTAllocated<Decl>, public Swi
   /// Returns the active `@backDeployed` attribute and the `AvailabilityRange`
   /// in which the decl is available as ABI.
   std::optional<std::pair<const BackDeployedAttr *, AvailabilityRange>>
-  getBackDeployedAttrAndRange(ASTContext &Ctx,
-                              bool forTargetVariant = false) const;
+  getBackDeployedAttrAndRange(bool forTargetVariant = false) const;
 
   /// Returns true if the decl has a valid and active `@backDeployed` attribute.
   bool isBackDeployed() const;

lib/AST/Decl.cpp

@@ -597,13 +597,13 @@ Decl::getIntroducedOSVersion(PlatformKind Kind) const {
 }
 
 std::optional<std::pair<const BackDeployedAttr *, AvailabilityRange>>
-Decl::getBackDeployedAttrAndRange(ASTContext &Ctx,
-                                  bool forTargetVariant) const {
-  if (auto *attr = getAttrs().getBackDeployed(Ctx, forTargetVariant)) {
+Decl::getBackDeployedAttrAndRange(bool forTargetVariant) const {
+  auto &ctx = getASTContext();
+  if (auto *attr = getAttrs().getBackDeployed(ctx, forTargetVariant)) {
     auto version = attr->getVersion();
     AvailabilityDomain ignoredDomain;
     AvailabilityInference::updateBeforeAvailabilityDomainForFallback(
-        attr, getASTContext(), ignoredDomain, version);
+        attr, ctx, ignoredDomain, version);
 
     // If the remap for fallback resulted in 1.0, then the
     // backdeployment prior to that is not meaningful.
@@ -615,14 +615,12 @@ Decl::getBackDeployedAttrAndRange(ASTContext &Ctx,
 
   // Accessors may inherit `@backDeployed`.
   if (auto *AD = dyn_cast<AccessorDecl>(this))
-    return AD->getStorage()->getBackDeployedAttrAndRange(Ctx, forTargetVariant);
+    return AD->getStorage()->getBackDeployedAttrAndRange(forTargetVariant);
 
   return std::nullopt;
 }
 
 bool Decl::isBackDeployed() const {
-  auto &Ctx = getASTContext();
-
   // A function declared in a local context can never be back-deployed.
   if (getDeclContext()->isLocalContext())
     return false;
@@ -636,11 +634,11 @@ bool Decl::isBackDeployed() const {
       return false;
   }
 
-  if (getBackDeployedAttrAndRange(Ctx))
+  if (getBackDeployedAttrAndRange())
     return true;
 
-  if (Ctx.LangOpts.TargetVariant) {
-    if (getBackDeployedAttrAndRange(Ctx, /*forTargetVariant=*/true))
+  if (getASTContext().LangOpts.TargetVariant) {
+    if (getBackDeployedAttrAndRange(/*forTargetVariant=*/true))
       return true;
   }
 
@@ -1482,7 +1480,7 @@ AvailabilityRange Decl::getAvailabilityForLinkage() const {
 
   // When computing availability for linkage, use the "before" version from
   // the @backDeployed attribute, if present.
-  if (auto backDeployedAttrAndRange = getBackDeployedAttrAndRange(ctx))
+  if (auto backDeployedAttrAndRange = getBackDeployedAttrAndRange())
     return backDeployedAttrAndRange->second;
 
   auto containingContext = AvailabilityInference::annotatedAvailableRange(this);

lib/SILGen/SILGenAvailability.cpp

@@ -113,9 +113,9 @@ static std::optional<AvailabilityQuery>
 getAvailabilityQueryForBackDeployment(AbstractFunctionDecl *AFD) {
   auto &ctx = AFD->getASTContext();
   if (ctx.LangOpts.TargetVariant) {
-    auto primaryAttrAndRange = AFD->getBackDeployedAttrAndRange(ctx);
+    auto primaryAttrAndRange = AFD->getBackDeployedAttrAndRange();
     auto variantAttrAndRange =
-        AFD->getBackDeployedAttrAndRange(ctx, /*forTargetVariant=*/true);
+        AFD->getBackDeployedAttrAndRange(/*forTargetVariant=*/true);
 
     if (!primaryAttrAndRange && !variantAttrAndRange)
       return std::nullopt;
@@ -134,7 +134,7 @@ getAvailabilityQueryForBackDeployment(AbstractFunctionDecl *AFD) {
                                       primaryRange, variantRange);
   }
 
-  if (auto primaryAttrAndRange = AFD->getBackDeployedAttrAndRange(ctx))
+  if (auto primaryAttrAndRange = AFD->getBackDeployedAttrAndRange())
     return AvailabilityQuery::dynamic(
         primaryAttrAndRange->first->getAvailabilityDomain(),
         primaryAttrAndRange->second, std::nullopt);
@@ -284,7 +284,7 @@ SILGenFunction::emitIfAvailableQuery(SILLocation loc,
 bool SILGenModule::requiresBackDeploymentThunk(ValueDecl *decl,
                                                ResilienceExpansion expansion) {
   auto &ctx = getASTContext();
-  auto attrAndRange = decl->getBackDeployedAttrAndRange(ctx);
+  auto attrAndRange = decl->getBackDeployedAttrAndRange();
   if (!attrAndRange)
     return false;
 

lib/Sema/TypeCheckAttr.cpp

@@ -5266,7 +5266,7 @@ void AttributeChecker::checkBackDeployedAttrs(
   std::map<PlatformKind, SourceLoc> seenPlatforms;
 
   const BackDeployedAttr *ActiveAttr = nullptr;
-  if (auto AttrAndRange = D->getBackDeployedAttrAndRange(Ctx))
+  if (auto AttrAndRange = D->getBackDeployedAttrAndRange())
     ActiveAttr = AttrAndRange->first;
 
   for (auto *Attr : Attrs) {