[tsan] Allow -fsanitize=thread for iOS-style simulator targets

[dcoughlin]

Summary

This patch updates the clang driver to allow -fsanitize=thread when targeting x86_64 iOS and tvOS simulators. It also restricts TSan targeting OS X to only be supported on x86_64 and not i386.

[dcoughlin]

There is a related patch for compiler-rt at http://reviews.llvm.org/D18277

[samsonov]

Cool, great to see this coming. I'll let Kuba sign this off.

test/Driver/fsanitize.c

220

Care to add a test for ios or tvos?

[kubamracek]

LGTM after adding a check for a simulator.

[dcoughlin]

Added tests for iOS and iOS simulators.

lib/Driver/ToolChains.cpp

 void Darwin::CheckObjCARC() const {
   if (isTargetIOSBased() || isTargetWatchOSBased() ||
       (isTargetMacOS() && !isMacosxVersionLT(10, 6)))
     return;
   getDriver().Diag(diag::err_arc_unsupported_on_toolchain);
 }
 
 SanitizerMask Darwin::getSupportedSanitizers() const {
+  const bool IsX86_64 = getTriple().getArch() == llvm::Triple::x86_64;
   SanitizerMask Res = ToolChain::getSupportedSanitizers();
   Res |= SanitizerKind::Address;
   if (isTargetMacOS()) {
     if (!isMacosxVersionLT(10, 9))
       Res |= SanitizerKind::Vptr;
     Res |= SanitizerKind::SafeStack;
+    if (IsX86_64)
+      Res |= SanitizerKind::Thread;
+  } else if (isTargetIOSSimulator() || isTargetTvOSSimulator()) {
+    if (IsX86_64)
       Res |= SanitizerKind::Thread;
   }
   return Res;
 }
 
 /// Generic_GCC - A tool chain using the 'gcc' command to perform
 /// all subcommands; this relies on gcc translating the majority of
 /// command line options.
 

test/Driver/fsanitize.c

 // RUN: %clang -target x86_64-apple-darwin10 -fsanitize=memory -fsanitize=thread,memory %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-MSAN-TSAN-MSAN-DARWIN
 // CHECK-MSAN-TSAN-MSAN-DARWIN: unsupported option '-fsanitize=memory' for target 'x86_64-apple-darwin10'
 // CHECK-MSAN-TSAN-MSAN-DARWIN-NOT: unsupported option
 
 // RUN: %clang -target x86_64-apple-darwin10 -fsanitize=thread,memory -fsanitize=memory %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-TSAN-MSAN-MSAN-DARWIN
 // CHECK-TSAN-MSAN-MSAN-DARWIN: unsupported option '-fsanitize=memory' for target 'x86_64-apple-darwin10'
 // CHECK-TSAN-MSAN-MSAN-DARWIN-NOT: unsupported option
 
+// RUN: %clang -target x86_64-apple-darwin -fsanitize=thread %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-TSAN-X86-64-DARWIN
+// CHECK-TSAN-X86-64-DARWIN-NOT: unsupported option
+
+// RUN: %clang -target x86_64-apple-iossimulator -fsanitize=thread %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-TSAN-X86-64-IOSSIMULATOR
+// CHECK-TSAN-X86-64-IOSSIMULATOR-NOT: unsupported option
+
+// RUN: %clang -target x86_64-apple-tvossimulator -fsanitize=thread %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-TSAN-X86-64-TVOSSIMULATOR
+// CHECK-TSAN-X86-64-TVOSSIMULATOR-NOT: unsupported option
+
+// RUN: %clang -target i386-apple-darwin -fsanitize=thread %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-TSAN-I386-DARWIN
+// CHECK-TSAN-I386-DARWIN: unsupported option '-fsanitize=thread' for target 'i386-apple-darwin'
+
+// RUN: %clang -target arm-apple-ios -fsanitize=thread %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-TSAN-ARM-IOS
+// CHECK-TSAN-ARM-IOS: unsupported option '-fsanitize=thread' for target 'arm-apple-ios'
+
+// RUN: %clang -target i386-apple-iossimulator -fsanitize=thread %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-TSAN-I386-IOSSIMULATOR
+// CHECK-TSAN-I386-IOSSIMULATOR: unsupported option '-fsanitize=thread' for target 'i386-apple-iossimulator'
+
+// RUN: %clang -target i386-apple-tvossimulator -fsanitize=thread %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-TSAN-I386-TVOSSIMULATOR
+// CHECK-TSAN-I386-TVOSSIMULATOR: unsupported option '-fsanitize=thread' for target 'i386-apple-tvossimulator'
+
 // RUN: %clang -target x86_64-apple-darwin10 -fsanitize=function %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-FSAN-DARWIN
 // CHECK-FSAN-DARWIN: unsupported option '-fsanitize=function' for target 'x86_64-apple-darwin10'
 
 // RUN: %clang -target x86_64-apple-darwin10 -fsanitize=function -fsanitize=undefined %s -### 2>&1 | FileCheck %s --check-prefix=CHECK-FSAN-UBSAN-DARWIN
 // CHECK-FSAN-UBSAN-DARWIN: unsupported option '-fsanitize=function' for target 'x86_64-apple-darwin10'
 
 // 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'