Add clang support for Objective-C application extensions.

This adds the -fapplication-extension option, along with the
ios_app_extension and macosx_app_extension availability attributes.
Patch by Ted Kremenek

llvm-svn: 230989

4 files changed, 34 insertions, 8 deletions

diff --git a/clang/lib/AST/DeclBase.cpp b/clang/lib/AST/DeclBase.cpp
index 75a219a4370..0390d81263a 100644
--- a/clang/lib/AST/DeclBase.cpp
+++ b/clang/lib/AST/DeclBase.cpp
@@ -336,20 +336,34 @@ bool Decl::isReferenced() const {
 static AvailabilityResult CheckAvailability(ASTContext &Context,
                                             const AvailabilityAttr *A,
                                             std::string *Message) {
-  StringRef TargetPlatform = Context.getTargetInfo().getPlatformName();
-  StringRef PrettyPlatformName
-    = AvailabilityAttr::getPrettyPlatformName(TargetPlatform);
-  if (PrettyPlatformName.empty())
-    PrettyPlatformName = TargetPlatform;
+  VersionTuple TargetMinVersion =
+    Context.getTargetInfo().getPlatformMinVersion();
 
-  VersionTuple TargetMinVersion = Context.getTargetInfo().getPlatformMinVersion();
   if (TargetMinVersion.empty())
     return AR_Available;
 
+  // Check if this is an App Extension "platform", and if so chop off
+  // the suffix for matching with the actual platform.
+  StringRef ActualPlatform = A->getPlatform()->getName();
+  StringRef RealizedPlatform = ActualPlatform;
+  if (Context.getLangOpts().AppExt) {
+    size_t suffix = RealizedPlatform.rfind("_app_extension");
+    if (suffix != StringRef::npos)
+      RealizedPlatform = RealizedPlatform.slice(0, suffix);
+  }
+
+  StringRef TargetPlatform = Context.getTargetInfo().getPlatformName();
+
   // Match the platform name.
-  if (A->getPlatform()->getName() != TargetPlatform)
+  if (RealizedPlatform != TargetPlatform)
     return AR_Available;
-  
+
+  StringRef PrettyPlatformName
+    = AvailabilityAttr::getPrettyPlatformName(ActualPlatform);
+
+  if (PrettyPlatformName.empty())
+    PrettyPlatformName = ActualPlatform;
+
   std::string HintMessage;
   if (!A->getMessage().empty()) {
     HintMessage = " - ";
diff --git a/clang/lib/Driver/Tools.cpp b/clang/lib/Driver/Tools.cpp
index de3d5a6af5c..eff0ca759a4 100644
--- a/clang/lib/Driver/Tools.cpp
+++ b/clang/lib/Driver/Tools.cpp
@@ -4216,6 +4216,10 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     }
   }
 
+  if (Args.hasFlag(options::OPT_fapplication_extension,
+                   options::OPT_fno_application_extension, false))
+    CmdArgs.push_back("-fapplication-extension");
+
   // Handle GCC-style exception args.
   if (!C.getDriver().IsCLMode())
     addExceptionArgs(Args, InputType, getToolChain(), KernelOrKext,
@@ -5811,6 +5815,12 @@ void darwin::Link::AddLinkArgs(Compilation &C,
   if (Args.hasArg(options::OPT_rdynamic) && Version[0] >= 137)
     CmdArgs.push_back("-export_dynamic");
 
+  // If we are using App Extension restrictions, pass a flag to the linker
+  // telling it that the compiled code has been audited.
+  if (Args.hasFlag(options::OPT_fapplication_extension,
+                   options::OPT_fno_application_extension, false))
+    CmdArgs.push_back("-application_extension");
+
   // If we are using LTO, then automatically create a temporary file path for
   // the linker to use, so that it's lifetime will extend past a possible
   // dsymutil step.
diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 2098dec1729..962e8e10df7 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -1578,6 +1578,7 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
   Opts.DebuggerObjCLiteral = Args.hasArg(OPT_fdebugger_objc_literal);
   Opts.ApplePragmaPack = Args.hasArg(OPT_fapple_pragma_pack);
   Opts.CurrentModule = Args.getLastArgValue(OPT_fmodule_name);
+  Opts.AppExt = Args.hasArg(OPT_fapplication_extension);
   Opts.ImplementationOfModule =
       Args.getLastArgValue(OPT_fmodule_implementation_of);
   Opts.ModuleFeatures = Args.getAllArgValues(OPT_fmodule_feature);
diff --git a/clang/lib/Lex/PPMacroExpansion.cpp b/clang/lib/Lex/PPMacroExpansion.cpp
index b986ada05a9..80ec3c45ce6 100644
--- a/clang/lib/Lex/PPMacroExpansion.cpp
+++ b/clang/lib/Lex/PPMacroExpansion.cpp
@@ -868,6 +868,7 @@ static bool HasFeature(const Preprocessor &PP, const IdentifierInfo *II) {
       .Case("attribute_analyzer_noreturn", true)
       .Case("attribute_availability", true)
       .Case("attribute_availability_with_message", true)
+      .Case("attribute_availability_app_extension", true)
       .Case("attribute_cf_returns_not_retained", true)
       .Case("attribute_cf_returns_retained", true)
       .Case("attribute_deprecated_with_message", true)