Support Swift in platform availability attribute

[michaelwu]

Summary

This adds support for Swift platform availability attributes. It's largely a port of the changes made to https://github.com/apple/swift-clang/ for Swift availability attributes. Specifically, https://github.com/apple/swift-clang/commit/84b5a21c31cb5b0d7d958a478bc01964939b6952 and https://github.com/apple/swift-clang/commit/e5b87f265aede41c8381094bbf54e2715c8293b0 . The implementation of attribute_availability_swift is a little different and additional tests in test/Index/availability.c were added.

[michaelwu]

Review ping

[jrmuizel]

Review ping

[jrmuizel]

Review ping

[aaron.ballman]

LGTM aside from a few small nits.

lib/Parse/ParseDecl.cpp

1005

You can use Platform->Ident->isStr("swift") here instead.

1007

Might as well switch the logic around to using isValid() instead.

lib/Sema/SemaDeclAttr.cpp

2368

II->isStr() here as well.

[michaelwu]

Thanks for the review! All requested changes have been made, and I also had to fix a test due to D50214

include/clang/Basic/Attr.td

return llvm::StringSwitch<llvm::StringRef>(Platform)
              .Case("ios", "iOS")
              .Case("macos", "macOS")
              .Case("tvos", "tvOS")
              .Case("watchos", "watchOS")
              .Case("ios_app_extension", "iOS (App Extension)")
              .Case("macos_app_extension", "macOS (App Extension)")
              .Case("tvos_app_extension", "tvOS (App Extension)")
              .Case("watchos_app_extension", "watchOS (App Extension)")
+             .Case("swift", "Swift")
              .Default(llvm::StringRef());
 }
 static llvm::StringRef getPlatformNameSourceSpelling(llvm::StringRef Platform) {
     return llvm::StringSwitch<llvm::StringRef>(Platform)
              .Case("ios", "iOS")
              .Case("macos", "macOS")
              .Case("tvos", "tvOS")
              .Case("watchos", "watchOS")

include/clang/Basic/DiagnosticSemaKinds.td

def warn_mismatched_availability_override_unavail : Warning<
   "available">,
   InGroup<Availability>;
 def warn_availability_on_static_initializer : Warning<
   "ignoring availability attribute %select{on '+load' method|"
   "with constructor attribute|with destructor attribute}0">,
   InGroup<Availability>;
 def note_overridden_method : Note<
   "overridden method is here">;
+def warn_availability_swift_unavailable_deprecated_only : Warning<
+  "only 'unavailable' and 'deprecated' are supported for Swift availability">,
+  InGroup<Availability>;
 def note_protocol_method : Note<
   "protocol method is here">;
 
 def warn_unguarded_availability :
   Warning<"%0 is only available on %1 %2 or newer">,
   InGroup<UnguardedAvailability>, DefaultIgnore;
 def warn_unguarded_availability_new :
   Warning<warn_unguarded_availability.Text>,

include/clang/Basic/Features.def

 FEATURE(attribute_availability_with_message, true)
 FEATURE(attribute_availability_app_extension, true)
 FEATURE(attribute_availability_with_version_underscores, true)
 FEATURE(attribute_availability_tvos, true)
 FEATURE(attribute_availability_watchos, true)
 FEATURE(attribute_availability_with_strict, true)
 FEATURE(attribute_availability_with_replacement, true)
 FEATURE(attribute_availability_in_templates, true)
+FEATURE(attribute_availability_swift, true)
 FEATURE(attribute_cf_returns_not_retained, true)
 FEATURE(attribute_cf_returns_retained, true)
 FEATURE(attribute_cf_returns_on_parameters, true)
 FEATURE(attribute_deprecated_with_message, true)
 FEATURE(attribute_deprecated_with_replacement, true)
 FEATURE(attribute_ext_vector_type, true)
 FEATURE(attribute_ns_returns_not_retained, true)
 FEATURE(attribute_ns_returns_retained, true)

lib/Parse/ParseDecl.cpp

if (Keyword == Ident_unavailable) {
       if (UnavailableLoc.isValid()) {
         Diag(KeywordLoc, diag::err_availability_redundant)
           << Keyword << SourceRange(UnavailableLoc);
       }
       UnavailableLoc = KeywordLoc;
       continue;
     }
 
+    if (Keyword == Ident_deprecated && Platform->Ident &&
+        Platform->Ident->getName() == "swift") {
+      // For swift, we deprecate for all versions.
+      if (!Changes[Deprecated].KeywordLoc.isInvalid()) {
+        Diag(KeywordLoc, diag::err_availability_redundant)
+          << Keyword
+          << SourceRange(Changes[Deprecated].KeywordLoc);
+      }
+
+      Changes[Deprecated].KeywordLoc = KeywordLoc;
+      // Use a fake version here.
+      Changes[Deprecated].Version = VersionTuple(1);
+      continue;
+    }
+
     if (Tok.isNot(tok::equal)) {
       Diag(Tok, diag::err_expected_after) << Keyword << tok::equal;
       SkipUntil(tok::r_paren, StopAtSemi);
       return;
     }
     ConsumeToken();
     if (Keyword == Ident_message || Keyword == Ident_replacement) {
       if (Tok.isNot(tok::string_literal)) {

lib/Sema/SemaDeclAttr.cpp

static void handleAvailabilityAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
   bool IsStrict = AL.getStrictLoc().isValid();
   StringRef Str;
   if (const auto *SE = dyn_cast_or_null<StringLiteral>(AL.getMessageExpr()))
     Str = SE->getString();
   StringRef Replacement;
   if (const auto *SE = dyn_cast_or_null<StringLiteral>(AL.getReplacementExpr()))
     Replacement = SE->getString();
 
+  if (II->getName() == "swift") {
+    if (Introduced.isValid() || Obsoleted.isValid() ||
+        (!IsUnavailable && !Deprecated.isValid())) {
+      S.Diag(AL.getLoc(),
+             diag::warn_availability_swift_unavailable_deprecated_only);
+      return;
+    }
+  }
+
   AvailabilityAttr *NewAttr = S.mergeAvailabilityAttr(ND, AL.getRange(), II,
                                                       false/*Implicit*/,
                                                       Introduced.Version,
                                                       Deprecated.Version,
                                                       Obsoleted.Version,
                                                       IsUnavailable, Str,
                                                       IsStrict, Replacement,
                                                       Sema::AMK_None,

test/Index/availability.c

 // Run lines below; this test is line- and column-sensitive.
 
 void foo(void) __attribute__((availability(macosx,introduced=10.4,deprecated=10.5,obsoleted=10.7), availability(ios,introduced=3.2,deprecated=4.1)));
 
 enum {
   old_enum
 } __attribute__((deprecated));
 
 enum {
   old_enum_plat
 } __attribute__((availability(macosx,introduced=10.4,deprecated=10.5,obsoleted=10.7)));
 
 void bar(void) __attribute__((availability(macosx,introduced=10.4))) __attribute__((availability(macosx,obsoleted=10.6))) __attribute__((availability(ios,introduced=3.2))) __attribute__((availability(macosx,deprecated=10.5,message="use foobar")));
 
 void bar2(void) __attribute__((availability(macosx,introduced=10.4,deprecated=10.5,obsoleted=10.7))) __attribute__((availability(ios,introduced=3.2,deprecated=10.0))) __attribute__((availability(macosx,introduced=10.4,deprecated=10.5,obsoleted=10.7))) __attribute__((availability(ios,introduced=3.2,deprecated=10.0)));
 
+void foo2(void) __attribute__((availability(swift,unavailable)));
+void foo3(void) __attribute__((availability(swift,deprecated)));
+
 // RUN: c-index-test -test-load-source all %s | FileCheck %s
 // CHECK: FunctionDecl=foo:3:6{{.*}}(ios, introduced=3.2, deprecated=4.1) (macos, introduced=10.4, deprecated=10.5, obsoleted=10.7)
 // CHECK: EnumConstantDecl=old_enum:6:3 (Definition) (deprecated)
 // CHECK: EnumConstantDecl=old_enum_plat:10:3 {{.*}} (macos, introduced=10.4, deprecated=10.5, obsoleted=10.7)
 // CHECK: FunctionDecl=bar:13:6{{.*}}(ios, introduced=3.2) (macos, introduced=10.4, deprecated=10.5, obsoleted=10.6, message="use foobar")
 // CHECK: FunctionDecl=bar2:15:6{{.*}}(ios, introduced=3.2, deprecated=10.0) (macos, introduced=10.4, deprecated=10.5, obsoleted=10.7)
+// CHECK: FunctionDecl=foo2:17:6{{.*}}(swift, unavailable)
+// CHECK: FunctionDecl=foo3:18:6{{.*}}(swift, deprecated=1)

test/Sema/attr-availability-swift.c

+// RUN: %clang_cc1 -triple x86_64-apple-darwin9 -fsyntax-only -fblocks -verify %s
+// RUN: %clang_cc1 -triple x86_64-apple-darwin9 -fsyntax-only -ast-dump %s | FileCheck %s
+//
+
+#if !__has_feature(attribute_availability_with_message)
+# error "Missing __has_feature"
+#endif
+
+#if __has_feature(attribute_availability_swift)
+# warning "okay"
+// expected-warning@-1{{okay}}
+#else
+# error "Missing __has_feature"
+#endif
+
+extern int noSwiftGlobal1 __attribute__((availability(swift, unavailable)));
+// CHECK: AvailabilityAttr {{.*}}swift 0 0 0 Unavailable "" ""
+extern int noSwiftGlobal1 __attribute__((availability(macosx, introduced=10.1))); // okay
+// CHECK: AvailabilityAttr {{.*}}macos 10.1 0 0 "" ""
+// CHECK: AvailabilityAttr {{.*}}Inherited swift 0 0 0 Unavailable "" ""
+extern int noSwiftGlobal1 __attribute__((availability(swift, unavailable, message="and this one has a message"))); // okay
+// CHECK: AvailabilityAttr {{.*}}swift 0 0 0 Unavailable "and this one has a message" ""
+// CHECK: AvailabilityAttr {{.*}}Inherited macos 10.1 0 0 "" ""
+extern int noSwiftGlobal2 __attribute__((availability(swift, introduced=5))); // expected-warning{{only 'unavailable' and 'deprecated' are supported for Swift availability}}
+// CHECK: VarDecl
+// CHECK-NOT: AvailabilityAttr
+extern int noSwiftGlobal3 __attribute__((availability(swift, deprecated, message="t")));
+// CHECK: VarDecl
+// CHECK: AvailabilityAttr {{.*}}swift 0 1 0 "t" ""