Add iOS/watchOS/tvOS support for ASan (clang part)

[zaks.anna]

Summary

Change the clang driver to accept ASan on iOS/watchOS/tvOS.

This change along with the corresponding changes in llvm and compiler-rt complete ASan support for iOS/watchOS/tvOS.

[kcc]

LGTM

[samsonov]

lib/Driver/ToolChains.cpp

368

Wait, this looks horrible. Can we teach toolchain to give us OS name?

[zaks.anna]

lib/Driver/ToolChains.cpp

368

These are not OS names; they are prefixes we use to name the library. I believe "appletvsimulator" would be a platform name, which is too long to append to the dylib name.

I could factor this out into a separate function, but there are no other immediate users. Not sure if the profiler library could be refactored to use it, logic there seems more complicated.

[samsonov]

Sorry, lost track of this.

lib/Driver/ToolChains.cpp

368

Then we can name it as getOSLibraryNamePrefix() or smth. like that. I worry that this logic would hardly be discoverable inside AddLinkSanitizerLibArgs if it's going to be reused somewhere (which is likely).

[zaks.anna]

Refactor the code to address Samsonov's review.

[zaks.anna]

I've introduced the helper function. Looks like addProfileRTLibs might be able to use it in the future (after support for autoconf is dropped) as well.

[samsonov]

Thanks.

lib/Driver/ToolChains.cpp

322

Fun fact: if TargetPlatform is TvOSSimulator, this function will return iossim because isTargetIOSSimulator will return true.
I suggest to just switch on the value of TargetPlatform instead of using these helpers.

330

Also, is it possible to add a test case for this?

[zaks.anna]

Thanks for spotting the bug! The bug is fixed and the tests are added in this revision.

[samsonov]

LGTM

lib/Driver/ToolChains.cpp

339

You might need llvm_unreachable at the very end to suppress GCC warnings (http://llvm.org/docs/CodingStandards.html#don-t-use-default-labels-in-fully-covered-switches-over-enumerations)

lib/Driver/ToolChains.cpp

if (AddRPath) {
 
     // Add the path to the resource dir to rpath to support using the dylib
     // from the default location without copying.
     CmdArgs.push_back("-rpath");
     CmdArgs.push_back(Args.MakeArgString(Dir));
   }
 }
 
 void Darwin::addProfileRTLibs(const ArgList &Args,
                               ArgStringList &CmdArgs) const {
   if (!needsProfileRT(Args)) return;
 
   // TODO: Clean this up once autoconf is gone
   SmallString<128> P(getDriver().ResourceDir);
   llvm::sys::path::append(P, "lib", "darwin");
   const char *Library = "libclang_rt.profile_osx.a";
 
   // Select the appropriate runtime library for the target.
   if (isTargetWatchOS()) {
     Library = "libclang_rt.profile_watchos.a";
   } else if (isTargetWatchOSSimulator()) {
     llvm::sys::path::append(P, "libclang_rt.profile_watchossim.a");
     Library = getVFS().exists(P) ? "libclang_rt.profile_watchossim.a"
                                  : "libclang_rt.profile_watchos.a";
   } else if (isTargetTvOS()) {
     Library = "libclang_rt.profile_tvos.a";
   } else if (isTargetTvOSSimulator()) {
     llvm::sys::path::append(P, "libclang_rt.profile_tvossim.a");
     Library = getVFS().exists(P) ? "libclang_rt.profile_tvossim.a"
                                  : "libclang_rt.profile_tvos.a";
   } else if (isTargetIPhoneOS()) {
     Library = "libclang_rt.profile_ios.a";
   } else if (isTargetIOSSimulator()) {
     llvm::sys::path::append(P, "libclang_rt.profile_iossim.a");

 void DarwinClang::AddLinkSanitizerLibArgs(const ArgList &Args,
                                           ArgStringList &CmdArgs,
                                           StringRef Sanitizer) const {
   if (!Args.hasArg(options::OPT_dynamiclib) &&
       !Args.hasArg(options::OPT_bundle)) {
     // Sanitizer runtime libraries requires C++.
     AddCXXStdlibLibArgs(Args, CmdArgs);
   }
-  // ASan is not supported on watchOS.
-  assert(isTargetMacOS() || isTargetIOSSimulator());
-  StringRef OS = isTargetMacOS() ? "osx" : "iossim";
+
+  StringRef OS = "";
+  if (isTargetMacOS())
+    OS = "osx";
+  if (isTargetWatchOSSimulator())
+    OS = "watchossim";
+  if (isTargetWatchOS())
+    OS = "watchos";
+  if (isTargetIOSSimulator())
+    OS = "iossim";
+  if (isTargetIPhoneOS())
+    OS = "ios";
+  if (isTargetTvOSSimulator())
+    OS = "tvossim";
+  if (isTargetTvOS())
+    OS = "tvos";
+  assert(!OS.empty());
+
   AddLinkRuntimeLib(
       Args, CmdArgs,
       (Twine("libclang_rt.") + Sanitizer + "_" + OS + "_dynamic.dylib").str(),
       /*AlwaysLink*/ true, /*IsEmbedded*/ false,
       /*AddRPath*/ true);
 
   if (GetCXXStdlibType(Args) == ToolChain::CST_Libcxx) {
     // Add explicit dependcy on -lc++abi, as -lc++ doesn't re-export
void Darwin::CheckObjCARC() const {
   if (isTargetIOSBased() || isTargetWatchOSBased() ||
       (isTargetMacOS() && !isMacosxVersionLT(10, 6)))
     return;
   getDriver().Diag(diag::err_arc_unsupported_on_toolchain);
 }
 
 SanitizerMask Darwin::getSupportedSanitizers() const {
   SanitizerMask Res = ToolChain::getSupportedSanitizers();
-  if (isTargetMacOS() || isTargetIOSSimulator())
-    Res |= SanitizerKind::Address;
   if (isTargetMacOS()) {
     if (!isMacosxVersionLT(10, 9))
       Res |= SanitizerKind::Vptr;
     Res |= SanitizerKind::SafeStack;
     Res |= SanitizerKind::Thread;
   }
   return Res;
 }

test/Driver/fsanitize.c

 
 // RUN: %clang -target x86_64-apple-darwin10 -mmacosx-version-min=10.8 -fsanitize=vptr %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-VPTR-DARWIN-OLD
 // CHECK-VPTR-DARWIN-OLD: unsupported option '-fsanitize=vptr' for target 'x86_64-apple-darwin10'
 
 // RUN: %clang -target x86_64-apple-darwin10 -mmacosx-version-min=10.9 -fsanitize=alignment,vptr %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-VPTR-DARWIN-NEW
 // CHECK-VPTR-DARWIN-NEW: -fsanitize=alignment,vptr
 
 // RUN: %clang -target armv7-apple-ios7 -miphoneos-version-min=7.0 -fsanitize=address %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-ASAN-IOS
-// CHECK-ASAN-IOS: unsupported option '-fsanitize=address' for target 'arm-apple-ios7'
+// CHECK-ASAN-IOS: -fsanitize=address
 
 // RUN: %clang -target i386-pc-openbsd -fsanitize=address %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-ASAN-OPENBSD
 // CHECK-ASAN-OPENBSD: unsupported option '-fsanitize=address' for target 'i386-pc-openbsd'
 
 // RUN: %clang -target x86_64-linux-gnu -fsanitize=cfi -flto -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-CFI
 // RUN: %clang -target x86_64-apple-darwin10 -fsanitize=cfi -flto -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-CFI
 // RUN: %clang -target x86_64-linux-gnu -fsanitize=cfi-derived-cast -flto -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-CFI-DCAST
 // RUN: %clang -target x86_64-linux-gnu -fsanitize=cfi-unrelated-cast -flto -c %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-CFI-UCAST