[driver][darwin] Set the 'simulator' environment when it's specified in '-target'

[arphaman]

Summary

This patch ensures that '-target' can be used to set the 'simulator' environment component in the target triple.

[steven_wu]

Other than the comment inline, LGTM.

lib/Driver/ToolChains/Darwin.cpp

1603–1605

Will be good to emit a warning for this. User should use -target with simulator or simulator deployment target.

[bob.wilson]

LGTM

lib/Driver/ToolChains/Darwin.cpp

1603–1605

Can we hold off on the warning and try to add that separately in the future? It would be good to first find out how often this code is being used. If there are a lot of uses, we may need to try to get people to stop relying on it before we add the warning. (I'm concerned about -Werror breaking builds with this.)

lib/Driver/ToolChains/Darwin.cpp

enum SourceKind {
     DeploymentTargetEnv,
     /// The OS was inferred from the SDK.
     InferredFromSDK,
     /// The OS was inferred from the -arch.
     InferredFromArch
   };
 
   using DarwinPlatformKind = Darwin::DarwinPlatformKind;
+  using DarwinEnvironmentKind = Darwin::DarwinEnvironmentKind;
 
   DarwinPlatformKind getPlatform() const { return Platform; }
 
+  DarwinEnvironmentKind getEnvironment() const { return Environment; }
+
   StringRef getOSVersion() const {
     if (Kind == OSVersionArg)
       return Argument->getValue();
     return OSVersion;
   }
 
   /// Returns true if the target OS was explicitly specified.
   bool isExplicitlySpecified() const { return Kind <= DeploymentTargetEnv; }
case InferredFromArch:
       return Argument->getAsString(Args);
     case DeploymentTargetEnv:
       return (llvm::Twine(EnvVarName) + "=" + OSVersion).str();
     }
     llvm_unreachable("Unsupported Darwin Source Kind");
   }
 
   static DarwinPlatform createFromTarget(llvm::Triple::OSType OS,
-                                         StringRef OSVersion, Arg *A) {
-    return DarwinPlatform(TargetArg, getPlatformFromOS(OS), OSVersion, A);
+                                         StringRef OSVersion, Arg *A,
+                                         llvm::Triple::EnvironmentType Env) {
+    DarwinPlatform Result(TargetArg, getPlatformFromOS(OS), OSVersion, A);
+    switch (Env) {
+    case llvm::Triple::Simulator:
+      Result.Environment = DarwinEnvironmentKind::Simulator;
+      break;
+    default:
+      break;
+    }
+    return Result;
   }
   static DarwinPlatform createOSVersionArg(DarwinPlatformKind Platform,
                                            Arg *A) {
     return DarwinPlatform(OSVersionArg, Platform, A);
   }
   static DarwinPlatform createDeploymentTargetEnv(DarwinPlatformKind Platform,
                                                   StringRef EnvVarName,
                                                   StringRef Value) {
case llvm::Triple::WatchOS:
       return DarwinPlatformKind::WatchOS;
     default:
       llvm_unreachable("Unable to infer Darwin variant");
     }
   }
 
   SourceKind Kind;
   DarwinPlatformKind Platform;
+  DarwinEnvironmentKind Environment = DarwinEnvironmentKind::NativeEnvironment;
   std::string OSVersion;
   Arg *Argument;
   StringRef EnvVarName;
 };
 
 /// Returns the deployment target that's specified using the -m<os>-version-min
 /// argument.
 Optional<DarwinPlatform>
Optional<DarwinPlatform> getDeploymentTargetFromTargetArg(
     DerivedArgList &Args, const llvm::Triple &Triple, const Driver &TheDriver) {
   if (!Args.hasArg(options::OPT_target))
     return None;
   if (Triple.getOS() == llvm::Triple::Darwin ||
       Triple.getOS() == llvm::Triple::UnknownOS)
     return None;
   std::string OSVersion = getOSVersion(Triple.getOS(), Triple, TheDriver);
   return DarwinPlatform::createFromTarget(Triple.getOS(), OSVersion,
-                                          Args.getLastArg(options::OPT_target));
+                                          Args.getLastArg(options::OPT_target),
+                                          Triple.getEnvironment());
 }
 
 } // namespace
 
 void Darwin::AddDeploymentTarget(DerivedArgList &Args) const {
   const OptTable &Opts = getDriver().getOpts();
 
   // Support allowing the SDKROOT environment variable used by xcrun and other
if (Platform == MacOS) {
     if (!Driver::GetReleaseVersion(OSTarget->getOSVersion(), Major, Minor,
                                    Micro, HadExtra) ||
         HadExtra || Major >= 10 || Minor >= 100 || Micro >= 100)
       getDriver().Diag(diag::err_drv_invalid_version_number)
           << OSTarget->getAsString(Args, Opts);
   } else
     llvm_unreachable("unknown kind of Darwin platform");
 
-  DarwinEnvironmentKind Environment = NativeEnvironment;
+  DarwinEnvironmentKind Environment = OSTarget->getEnvironment();
   // Recognize iOS targets with an x86 architecture as the iOS simulator.
-  if (Platform != MacOS && (getTriple().getArch() == llvm::Triple::x86 ||
-                            getTriple().getArch() == llvm::Triple::x86_64))
+  if (Environment == NativeEnvironment && Platform != MacOS &&
+      (getTriple().getArch() == llvm::Triple::x86 ||
     Environment = Simulator;
 
   setTarget(Platform, Environment, Major, Minor, Micro);
 
   if (const Arg *A = Args.getLastArg(options::OPT_isysroot)) {
     StringRef SDK = getSDKName(A->getValue());
     if (SDK.size() > 0) {
       size_t StartVer = SDK.find_first_of("0123456789");

test/Driver/darwin-version.c

 // RUN: FileCheck --check-prefix=CHECK-VERSION-TTVOS-SDK %s
 // CHECK-VERSION-TTVOS-SDK: thumbv7-apple-tvos9
 
 // Target with OS version is not overriden by arch:
 
 // RUN: %clang -target uknown-apple-macos10.11.2 -arch=armv7k -c %s -### 2>&1 | \
 // RUN:   FileCheck --check-prefix=CHECK-VERSION-TIGNORE-ARCH1 %s
 // CHECK-VERSION-TIGNORE-ARCH1: "unknown-apple-macosx10.11.2"
+
+// Target can be used to specify the environment:
+
+// RUN: %clang -target x86_64-apple-ios11-simulator -c %s -### 2>&1 | \
+// RUN:   FileCheck --check-prefix=CHECK-VERSION-TENV-SIM1 %s
+// CHECK-VERSION-TENV-SIM1: "x86_64-apple-ios11.0.0-simulator"
+
+// RUN: %clang -target armv7k-apple-ios10.1-simulator -c %s -### 2>&1 | \
+// RUN:   FileCheck --check-prefix=CHECK-VERSION-TENV-SIM2 %s
+// CHECK-VERSION-TENV-SIM2: "thumbv7k-apple-ios10.1.0-simulator"