Merge pull request #78284 from tshortli/semantic-available-attr

AST: Introduce `SemanticAvailableAttr`

Author: tshortli

include/swift/AST/Attr.h

@@ -20,6 +20,7 @@
 #include "swift/AST/ASTAllocated.h"
 #include "swift/AST/AttrKind.h"
 #include "swift/AST/AutoDiff.h"
+#include "swift/AST/AvailabilityDomain.h"
 #include "swift/AST/ConcreteDeclRef.h"
 #include "swift/AST/DeclNameLoc.h"
 #include "swift/AST/Identifier.h"
@@ -782,12 +783,6 @@ class AvailableAttr : public DeclAttribute {
   /// Indicates where the Obsoleted version was specified.
   const SourceRange ObsoletedRange;
 
-  /// Whether this is a language-version-specific entity.
-  bool isLanguageVersionSpecific() const;
-
-  /// Whether this is a PackageDescription version specific entity.
-  bool isPackageDescriptionVersionSpecific() const;
-
   /// Whether this is an unconditionally unavailable entity.
   bool isUnconditionallyUnavailable() const;
 
@@ -831,17 +826,6 @@ class AvailableAttr : public DeclAttribute {
   /// Returns true if this attribute is active given the current platform.
   bool isActivePlatform(const ASTContext &ctx) const;
 
-  /// Returns the active version from the AST context corresponding to
-  /// the available kind. For example, this will return the effective language
-  /// version for swift version-specific availability kind, PackageDescription
-  /// version for PackageDescription version-specific availability.
-  llvm::VersionTuple getActiveVersion(const ASTContext &ctx) const;
-
-  /// Compare this attribute's version information against the platform or
-  /// language version (assuming the this attribute pertains to the active
-  /// platform).
-  AvailableVersionComparison getVersionAvailability(const ASTContext &ctx) const;
-
   /// Create an AvailableAttr that indicates specific availability
   /// for all platforms.
   static AvailableAttr *
@@ -3190,6 +3174,95 @@ class ParsedDeclAttributes {
   }
 };
 
+/// A wrapper for `AvailableAttr` that is enriched with additional semantic
+/// informaton, like its corresponding `AvailabilityDomain`.
+class SemanticAvailableAttr final {
+  const AvailableAttr *attr;
+  const AvailabilityDomain domain;
+
+public:
+  SemanticAvailableAttr(const AvailableAttr *attr, AvailabilityDomain domain)
+      : attr(attr), domain(domain) {
+    assert(attr);
+  }
+
+  const AvailableAttr *getParsedAttr() const { return attr; }
+  const AvailabilityDomain getDomain() const { return domain; }
+
+  /// Returns the platform kind that the attribute applies to, or
+  /// `PlatformKind::none` if the attribute is not platform specific.
+  bool isPlatformSpecific() const { return domain.isPlatform(); }
+
+  /// Returns the platform kind that the attribute applies to, or
+  /// `PlatformKind::none` if the attribute is not platform specific.
+  PlatformKind getPlatformKind() const { return domain.getPlatformKind(); }
+
+  /// Whether this attribute has an introduced, deprecated, or obsoleted
+  /// version.
+  bool isVersionSpecific() const {
+    return attr->Introduced || attr->Deprecated || attr->Obsoleted;
+  }
+
+  /// Whether this is a language mode specific attribute.
+  bool isSwiftLanguageModeSpecific() const {
+    return domain.isSwiftLanguage() && isVersionSpecific();
+  }
+
+  /// Whether this is a PackageDescription version specific attribute.
+  bool isPackageDescriptionVersionSpecific() const {
+    return domain.isPackageDescription() && isVersionSpecific();
+  }
+
+  /// Returns the active version from the AST context corresponding to
+  /// the available kind. For example, this will return the effective language
+  /// version for swift version-specific availability kind, PackageDescription
+  /// version for PackageDescription version-specific availability.
+  llvm::VersionTuple getActiveVersion(const ASTContext &ctx) const;
+
+  /// Compare this attribute's version information against the platform or
+  /// language version (assuming the this attribute pertains to the active
+  /// platform).
+  AvailableVersionComparison
+  getVersionAvailability(const ASTContext &ctx) const;
+
+  /// Returns true if this attribute is considered active in the current
+  /// compilation context.
+  bool isActive(ASTContext &ctx) const;
+};
+
+/// An iterable range of `SemanticAvailableAttr`s.
+class SemanticAvailableAttributes {
+public:
+  class Filter final {
+    const Decl *decl;
+    bool includeInactive;
+
+  public:
+    Filter(const Decl *decl, bool includeInactive)
+        : decl(decl), includeInactive(includeInactive) {}
+
+    std::optional<SemanticAvailableAttr>
+    operator()(const DeclAttribute *attr) const;
+  };
+
+  using Range =
+      OptionalTransformRange<iterator_range<DeclAttributes::const_iterator>,
+                             Filter>;
+
+private:
+  Range attrRange;
+
+public:
+  SemanticAvailableAttributes(const DeclAttributes &attrs, const Decl *decl,
+                              bool includeInactive = false)
+      : attrRange(make_range(attrs.begin(), attrs.end()),
+                  Filter(decl, includeInactive)) {}
+
+  Range::iterator begin() const { return attrRange.begin(); }
+  Range::iterator end() const { return attrRange.end(); }
+  bool empty() const { return attrRange.empty(); }
+};
+
 class alignas(1 << AttrAlignInBits) TypeAttribute
     : public ASTAllocated<TypeAttribute> {
 protected:

include/swift/AST/Availability.h

@@ -380,7 +380,8 @@ class AvailabilityInference {
   annotatedAvailableRange(const Decl *D);
 
   static AvailabilityRange
-  annotatedAvailableRangeForAttr(const SpecializeAttr *attr, ASTContext &ctx);
+  annotatedAvailableRangeForAttr(const Decl *D, const SpecializeAttr *attr,
+                                 ASTContext &ctx);
 
   /// For the attribute's introduction version, update the platform and version
   /// values to the re-mapped platform's, if using a fallback platform.

include/swift/AST/AvailabilityDomain.h

@@ -22,6 +22,7 @@
 #include "swift/Basic/LLVM.h"
 
 namespace swift {
+class ASTContext;
 
 /// Represents a dimension of availability (e.g. macOS platform or Swift
 /// language mode).
@@ -83,10 +84,11 @@ class AvailabilityDomain final {
   bool isPackageDescription() const { return kind == Kind::PackageDescription; }
 
   /// Returns the platform kind for this domain if applicable.
-  PlatformKind getPlatformKind() const {
-    assert(kind == Kind::Platform);
-    return platform;
-  }
+  PlatformKind getPlatformKind() const { return platform; }
+
+  /// Returns true if this domain is considered active in the current
+  /// compilation context.
+  bool isActive(ASTContext &ctx) const;
 
   /// Returns the string to use in diagnostics to identify the domain. May
   /// return an empty string.

include/swift/AST/Decl.h

@@ -1395,9 +1395,18 @@ class alignas(1 << DeclAlignInBits) Decl : public ASTAllocated<Decl>, public Swi
   /// and its DeclContext does not.
   bool isOutermostPrivateOrFilePrivateScope() const;
 
-  /// Returns the availability domain associated with the given `AvailableAttr`
-  /// that is attached to this decl.
-  AvailabilityDomain getDomainForAvailableAttr(const AvailableAttr *attr) const;
+  /// Returns an iterable list of the valid `AvailableAttr` and
+  /// `AvailabilityDomain` pairs. Unless \p includeInactive is true, attributes
+  /// that are considered inactive for the compilation context are filtered out.
+  SemanticAvailableAttributes
+  getSemanticAvailableAttrs(bool includeInactive = true) const;
+
+  /// Returns the SemanticAvailableAttr associated with the given
+  /// `AvailableAttr` that is attached to this decl. Returns `std::nullopt` if a
+  /// valid semantic version of the attribute cannot be constructed (e.g. the
+  /// domain cannot be resolved).
+  std::optional<SemanticAvailableAttr>
+  getSemanticAvailableAttr(const AvailableAttr *attr) const;
 
   /// Returns the active platform-specific `@available` attribute for this decl.
   /// There may be multiple `@available` attributes that are relevant to the

include/swift/AST/PrintOptions.h

@@ -341,9 +341,6 @@ struct PrintOptions {
   /// Whether to print the internal layout name instead of AnyObject, etc.
   bool PrintInternalLayoutName = false;
 
-  /// Suppress emitting @available(*, noasync)
-  bool SuppressNoAsyncAvailabilityAttr = false;
-
   /// Suppress emitting isolated or async deinit, and emit open containing class
   /// as public
   bool SuppressIsolatedDeinit = false;

lib/APIDigester/ModuleAnalyzerNodes.cpp

@@ -1339,14 +1339,16 @@ std::optional<uint8_t> SDKContext::getFixedBinaryOrder(ValueDecl *VD) const {
 // check for if it has @available(macOS 9999, iOS 9999, tvOS 9999, watchOS 9999, *)
 static bool isABIPlaceHolder(Decl *D) {
   llvm::SmallSet<PlatformKind, 4> Platforms;
-  for (auto *ATT: D->getAttrs()) {
-    if (auto *AVA = dyn_cast<AvailableAttr>(ATT)) {
-      if (AVA->getPlatform() != PlatformKind::none && AVA->Introduced &&
-          AVA->Introduced->getMajor() == 9999) {
-        Platforms.insert(AVA->getPlatform());
-      }
+  for (auto semanticAttr : D->getSemanticAvailableAttrs()) {
+    auto attr = semanticAttr.getParsedAttr();
+    auto domain = semanticAttr.getDomain();
+    if (domain.isPlatform() && attr->Introduced &&
+        attr->Introduced->getMajor() == 9999) {
+      Platforms.insert(attr->getPlatform());
     }
   }
+
+  // FIXME: This probably isn't correct anymore, now that visionOS exists
   return Platforms.size() == 4;
 }
 
@@ -1361,11 +1363,11 @@ static bool isABIPlaceholderRecursive(Decl *D) {
 StringRef SDKContext::getPlatformIntroVersion(Decl *D, PlatformKind Kind) {
   if (!D)
     return StringRef();
-  for (auto *ATT: D->getAttrs()) {
-    if (auto *AVA = dyn_cast<AvailableAttr>(ATT)) {
-      if (AVA->getPlatform() == Kind && AVA->Introduced) {
-        return buffer(AVA->Introduced->getAsString());
-      }
+  for (auto semanticAttr : D->getSemanticAvailableAttrs()) {
+    auto attr = semanticAttr.getParsedAttr();
+    auto domain = semanticAttr.getDomain();
+    if (domain.getPlatformKind() == Kind && attr->Introduced) {
+      return buffer(attr->Introduced->getAsString());
     }
   }
   return StringRef();
@@ -1374,11 +1376,12 @@ StringRef SDKContext::getPlatformIntroVersion(Decl *D, PlatformKind Kind) {
 StringRef SDKContext::getLanguageIntroVersion(Decl *D) {
   if (!D)
     return StringRef();
-  for (auto *ATT: D->getAttrs()) {
-    if (auto *AVA = dyn_cast<AvailableAttr>(ATT)) {
-      if (AVA->isLanguageVersionSpecific() && AVA->Introduced) {
-        return buffer(AVA->Introduced->getAsString());
-      }
+  for (auto semanticAttr : D->getSemanticAvailableAttrs()) {
+    auto attr = semanticAttr.getParsedAttr();
+    auto domain = semanticAttr.getDomain();
+
+    if (domain.isSwiftLanguage() && attr->Introduced) {
+      return buffer(attr->Introduced->getAsString());
     }
   }
   return getLanguageIntroVersion(D->getDeclContext()->getAsDecl());