[cuda] Driver changes to build and stitch together host and device-side CUDA code.

[tra]

Summary

The changes were extracted from D8463 to separate driver part from the rest.

• Changed driver pipeline to compile host and device sides of CUDA files and pack device-side results into host object file.
• Added tests for cuda pipeline creation in driver.

Differential Revision: http://reviews.llvm.org/D8463

[echristo]

Mostly requests for comments etc.

This is terrible, I just don't have any better ideas. :)

-eric

include/clang/Driver/Action.h

142

AtTopLevel needs to be documented more. It's not clear. Also the usage below.

lib/Driver/Driver.cpp

1171

"For each"

1199–1240

Needs some overarching documentation.

tools/libclang/CIndex.cpp

3031

Comment.

[tra]

More comments...

[tra]

Added more comments.

include/clang/Driver/Action.h

142

Commented.

lib/Driver/Driver.cpp

1171

Fixed.

1199–1240

Added more comments describing what's happening in this function.

tools/libclang/CIndex.cpp

3031

Done.

[echristo]

Not really happy with the getTargetToolChain changes. Can you go ahead and revisit the necessity of those (and probably the naming of the StringRef argument as well)?

Thanks!

-eric

[tra]

Added more comments.
Cleaned up job creation for CudaDeviceAction so it no longer uses computeTargetTriple directly.
Removed -nocudainc argument (which does not exist yet) from the test case RUN lines.

[tra]

In D9509#167188, @echristo wrote:

Not really happy with the getTargetToolChain changes. Can you go ahead and revisit the necessity of those (and probably the naming of the StringRef argument as well)?

getToolChain does two things -- calculates a triple based on default triple, command line args and optional DarwinArch and then selects a toolchain based on the triple. I needed toolchain selection by triple, so I've extracted it into getTargetToolChain.

Alternative approach would be to extend computeTargetTriple so that it can figure out that I need to get a NVPTX triple based on DarwinArchName (renamed to ArchName?). IMO it's not as clean as using getTargetToolchain(Triple) considering that we already know the triple.

I've changed the code so it no longer uses computeTargetTriple() directly (and removed forward declaration), but kept getTargetToolchain().

[tra]

Fixed a problem with device-side inputs being added to host's cc1 command line twice.

[tra]

Eric,

Did you get a chance to take a look at cleaned up getTargetToolChain() and ?

--Artem

[tra]

Oops. Hit "Sent" accidentally..

[echristo]

Couple of inline comments, and I'm still not a huge fan of the getTargetToolChain bits. It seems like we should be able to have a single interface to getting a target toolchain that works for both cases. Maybe compute the triple up front for use in the rest of the driver for the host?

Good lord cuda is terrible. :)

-eric

include/clang/Driver/Driver.h

412–414

The comments no longer match the code here.

lib/Driver/Driver.cpp

822–823

Can you rearrange the code so that it doesn't need the forward declaration?

[tra]

In D9509#200597, @echristo wrote:

Couple of inline comments, and I'm still not a huge fan of the getTargetToolChain bits. It seems like we should be able to have a single interface to getting a target toolchain that works for both cases. Maybe compute the triple up front for use in the rest of the driver for the host?

Existing code commingles two independent things -- figuring out target triple value and retrieving corresponding ToolChain for a given Triple. My change just refactored out Triple->ToolChain mapping.

Good lord cuda is terrible. :)

'Quirky' would be a better word, perhaps.

include/clang/Driver/Driver.h

412–414

I believe it still does. My change just split StringRef -> Triple -> Toolchain conversion into StringRaf->Triple and Tuple->ToolChain without change in functionality.

lib/Driver/Driver.cpp

822–823

Nope. PrintActions1 and PrintActionList call each other recursively. At least one of them must have forward declaration.

[dougk]

lib/Driver/Driver.cpp

822–823

you could move PrintActionList back into PrintActions1 so that the "gpu binaries" clause and final clause each fall into some common code that performs the equivalent of what is now your PrintActionList function. (i.e. don't use mutually recursive functions)

If nothing else, consider renaming PrintActionList so not to imply that it performs the printing, perhaps "ActionListAsString". And use a range-based for loop.

lib/Driver/ToolChains.h

692

CudaToolChain would be are more readily understandable name.

[tra]

Addressed dougk@ and echristo@ comments:

• folded PrintActionList back into PrintActions1 and got rid of forward declaration.
• gave cuda toolchain more descriptive name
• minor formatting and test cases fixes.

[tra]

lib/Driver/Driver.cpp

822–823

Good point. Folded PrintActionList back into PrintActions1 as you suggested.

[tra]

Removed getToolCahin changes that were reviewed/committed in D11105.

[echristo]

This is a good start. We'll probably want to do some more refactoring, but this gets it in so we can look at it and make those decisions.

Make sure everything is formatted with clang-format, then LGTM.

-eric

lib/Driver/Driver.cpp

822–823

Bleh. OK.

lib/Driver/ToolChains.cpp

3629–3631

Formatting?

[tra]

clang-formatted the patch. No functional changes.

[tra]

Committed in r242085.

include/clang/Driver/Action.h

 public:
   typedef ActionList::size_type size_type;
   typedef ActionList::iterator iterator;
   typedef ActionList::const_iterator const_iterator;
 
   enum ActionClass {
     InputClass = 0,
     BindArchClass,
+    CudaDeviceClass,
+    CudaHostClass,
     PreprocessJobClass,
     PrecompileJobClass,
     AnalyzeJobClass,
     MigrateJobClass,
     CompileJobClass,
     BackendJobClass,
     AssembleJobClass,
     LinkJobClass,
public:
 
   const char *getArchName() const { return ArchName; }
 
   static bool classof(const Action *A) {
     return A->getKind() == BindArchClass;
   }
 };
 
+class CudaDeviceAction : public Action {
+  virtual void anchor();
+  /// GPU architecture to bind -- e.g 'sm_35'.
+  const char *GpuArchName;
+  /// True when action results are not consumed by the host action (e.g when
+  /// -fsyntax-only or --cuda-device-only options are used).
+  bool AtTopLevel;
+
+public:
+  CudaDeviceAction(std::unique_ptr<Action> Input, const char *ArchName,
+                   bool AtTopLevel);
+
+  const char *getGpuArchName() const { return GpuArchName; }
+  bool isAtTopLevel() const { return AtTopLevel; }
+
+  static bool classof(const Action *A) {
+    return A->getKind() == CudaDeviceClass;
+  }
+};
+
+class CudaHostAction : public Action {
+  virtual void anchor();
+  ActionList DeviceActions;
+
+public:
+  CudaHostAction(std::unique_ptr<Action> Input,
+                 const ActionList &DeviceActions);
+  ~CudaHostAction() override;
+
+  ActionList &getDeviceActions() { return DeviceActions; }
+  const ActionList &getDeviceActions() const { return DeviceActions; }
+
+  static bool classof(const Action *A) { return A->getKind() == CudaHostClass; }
+};
+
 class JobAction : public Action {
   virtual void anchor();
 protected:
   JobAction(ActionClass Kind, std::unique_ptr<Action> Input, types::ID Type);
   JobAction(ActionClass Kind, const ActionList &Inputs, types::ID Type);
 
 public:
   static bool classof(const Action *A) {

include/clang/Driver/Driver.h

public:
 
   bool IsUsingLTO(const ToolChain &TC, const llvm::opt::ArgList &Args) const;
 
 private:
   /// \brief Retrieves a ToolChain for a particular target triple.
   ///
   /// Will cache ToolChains for the life of the driver object, and create them
   /// on-demand.
+  const ToolChain &getTargetToolChain(const llvm::opt::ArgList &Args,
+                                      const llvm::Triple &Target) const;
+
   const ToolChain &getToolChain(const llvm::opt::ArgList &Args,
                                 StringRef DarwinArchName = "") const;
 
   /// @}
 
   /// \brief Get bitmasks for which option flags to include and exclude based on
   /// the driver mode.
   std::pair<unsigned, unsigned> getIncludeExcludeOptionFlagMasks() const;

include/clang/Driver/Options.td

 def coverage : Flag<["-", "--"], "coverage">;
 def cpp_precomp : Flag<["-"], "cpp-precomp">, Group<clang_ignored_f_Group>;
 def current__version : JoinedOrSeparate<["-"], "current_version">;
 def cxx_isystem : JoinedOrSeparate<["-"], "cxx-isystem">, Group<clang_i_Group>,
   HelpText<"Add directory to the C++ SYSTEM include search path">, Flags<[CC1Option]>,
   MetaVarName<"<directory>">;
 def c : Flag<["-"], "c">, Flags<[DriverOption]>,
   HelpText<"Only run preprocess, compile, and assemble steps">;
+def cuda_device_only : Flag<["--"], "cuda-device-only">,
+  HelpText<"Do device-side CUDA compilation only">;
+def cuda_gpu_arch_EQ : Joined<["--"], "cuda-gpu-arch=">,
+  Flags<[DriverOption, HelpHidden]>, HelpText<"CUDA GPU architecture">;
+def cuda_host_only : Flag<["--"], "cuda-host-only">,
+  HelpText<"Do host-side CUDA compilation only">;
 def dA : Flag<["-"], "dA">, Group<d_Group>;
 def dD : Flag<["-"], "dD">, Group<d_Group>, Flags<[CC1Option]>,
   HelpText<"Print macro definitions in -E mode in addition to normal output">;
 def dM : Flag<["-"], "dM">, Group<d_Group>, Flags<[CC1Option]>,
   HelpText<"Print macro definitions in -E mode instead of normal output">;
 def dead__strip : Flag<["-"], "dead_strip">;
 def dependency_file : Separate<["-"], "dependency-file">, Flags<[CC1Option]>,
   HelpText<"Filename (or -) to write dependency output to">;

include/clang/Driver/Types.h

#undef TYPE
   bool canLipoType(ID Id);
 
   /// isAcceptedByClang - Can clang handle this input type.
   bool isAcceptedByClang(ID Id);
 
   /// isCXX - Is this a "C++" input (C++ and Obj-C++ sources and headers).
   bool isCXX(ID Id);
 
+  /// isCuda - Is this a CUDA input.
+  bool isCuda(ID Id);
+
   /// isObjC - Is this an "ObjC" input (Obj-C and Obj-C++ sources and headers).
   bool isObjC(ID Id);
 
   /// lookupTypeForExtension - Lookup the type to use for the file
   /// extension \p Ext.
   ID lookupTypeForExtension(const char *Ext);
 
   /// lookupTypeForTypSpecifier - Lookup the type to use for a user

include/clang/Driver/Types.def

 
 
 // C family source language (with and without preprocessing).
 TYPE("cpp-output",               PP_C,         INVALID,         "i",     "u")
 TYPE("c",                        C,            PP_C,            "c",     "u")
 TYPE("cl",                       CL,           PP_C,            "cl",    "u")
 TYPE("cuda-cpp-output",          PP_CUDA,      INVALID,         "cui",   "u")
 TYPE("cuda",                     CUDA,         PP_CUDA,         "cu",    "u")
+TYPE("cuda",                     CUDA_DEVICE,  PP_CUDA,         "cu",    "")
 TYPE("objective-c-cpp-output",   PP_ObjC,      INVALID,         "mi",    "u")
 TYPE("objc-cpp-output",          PP_ObjC_Alias, INVALID,        "mi",    "u")
 TYPE("objective-c",              ObjC,         PP_ObjC,         "m",     "u")
 TYPE("c++-cpp-output",           PP_CXX,       INVALID,         "ii",    "u")
 TYPE("c++",                      CXX,          PP_CXX,          "cpp",   "u")
 TYPE("objective-c++-cpp-output", PP_ObjCXX,    INVALID,         "mii",   "u")
 TYPE("objc++-cpp-output",        PP_ObjCXX_Alias, INVALID,      "mii",   "u")
 TYPE("objective-c++",            ObjCXX,       PP_ObjCXX,       "mm",    "u")

lib/Driver/Action.cpp

for (iterator it = begin(), ie = end(); it != ie; ++it)
       delete *it;
   }
 }
 
 const char *Action::getClassName(ActionClass AC) {
   switch (AC) {
   case InputClass: return "input";
   case BindArchClass: return "bind-arch";
+  case CudaDeviceClass: return "cuda-device";
+  case CudaHostClass: return "cuda-host";
   case PreprocessJobClass: return "preprocessor";
   case PrecompileJobClass: return "precompiler";
   case AnalyzeJobClass: return "analyzer";
   case MigrateJobClass: return "migrator";
   case CompileJobClass: return "compiler";
   case BackendJobClass: return "backend";
   case AssembleJobClass: return "assembler";
   case LinkJobClass: return "linker";

 }
 
 void BindArchAction::anchor() {}
 
 BindArchAction::BindArchAction(std::unique_ptr<Action> Input,
                                const char *_ArchName)
     : Action(BindArchClass, std::move(Input)), ArchName(_ArchName) {}
 
+void CudaDeviceAction::anchor() {}
+
+CudaDeviceAction::CudaDeviceAction(std::unique_ptr<Action> Input,
+                                   const char *ArchName, bool AtTopLevel)
+    : Action(CudaDeviceClass, std::move(Input)), GpuArchName(ArchName),
+      AtTopLevel(AtTopLevel) {}
+
+void CudaHostAction::anchor() {}
+
+CudaHostAction::CudaHostAction(std::unique_ptr<Action> Input,
+                               const ActionList &_DeviceActions)
+    : Action(CudaHostClass, std::move(Input)), DeviceActions(_DeviceActions) {}
+
+CudaHostAction::~CudaHostAction() {
+  for (iterator it = DeviceActions.begin(), ie = DeviceActions.end(); it != ie;
+       ++it)
+    delete *it;
+}
+
 void JobAction::anchor() {}
 
 JobAction::JobAction(ActionClass Kind, std::unique_ptr<Action> Input,
                      types::ID Type)
     : Action(Kind, std::move(Input), Type) {}
 
 JobAction::JobAction(ActionClass Kind, const ActionList &Inputs, types::ID Type)
   : Action(Kind, Inputs, Type) {

lib/Driver/Driver.cpp

// -{fsyntax-only,-analyze,emit-ast} only run up to the compiler.
                                         options::OPT__analyze_auto)) ||
              (PhaseArg = DAL.getLastArg(options::OPT_emit_ast))) {
     FinalPhase = phases::Compile;
 
     // -S only runs up to the backend.
   } else if ((PhaseArg = DAL.getLastArg(options::OPT_S))) {
     FinalPhase = phases::Backend;
 
-    // -c only runs up to the assembler.
-  } else if ((PhaseArg = DAL.getLastArg(options::OPT_c))) {
+    // -c and partial CUDA compilations only run up to the assembler.
+  } else if ((PhaseArg = DAL.getLastArg(options::OPT_c)) ||
+             (PhaseArg = DAL.getLastArg(options::OPT_cuda_device_only)) ||
+             (PhaseArg = DAL.getLastArg(options::OPT_cuda_host_only))) {
     FinalPhase = phases::Assemble;
-
     // Otherwise do everything.
   } else
     FinalPhase = phases::Link;
 
   if (FinalPhaseArg)
     *FinalPhaseArg = PhaseArg;
 
   return FinalPhase;
if (C.getArgs().hasArg(options::OPT_print_multi_os_directory)) {
     // "lib/../lib32" as appropriate for the toolchain. For now, print
     // nothing because it's not supported yet.
     return false;
   }
 
   return true;
 }
 
 static unsigned PrintActions1(const Compilation &C, Action *A,
-                              std::map<Action*, unsigned> &Ids) {
+                              std::map<Action *, unsigned> &Ids);
+
+static std::string PrintActionList(const Compilation &C, ActionList &AL,
+                                   std::map<Action *, unsigned> &Ids) {
+  std::string str;
+  llvm::raw_string_ostream os(str);
+  os << "{";
+  for (Action::iterator it = AL.begin(), ie = AL.end(); it != ie;) {
+    os << PrintActions1(C, *it, Ids);
+    ++it;
+    if (it != ie)
+      os << ", ";
+  }
+  os << "}";
+  return str;
+}
+
+static unsigned PrintActions1(const Compilation &C, Action *A,
+                              std::map<Action *, unsigned> &Ids) {
   if (Ids.count(A))
     return Ids[A];
 
   std::string str;
   llvm::raw_string_ostream os(str);
 
   os << Action::getClassName(A->getKind()) << ", ";
   if (InputAction *IA = dyn_cast<InputAction>(A)) {
     os << "\"" << IA->getInputArg().getValue() << "\"";
   } else if (BindArchAction *BIA = dyn_cast<BindArchAction>(A)) {
     os << '"' << BIA->getArchName() << '"'
        << ", {" << PrintActions1(C, *BIA->begin(), Ids) << "}";
+  } else if (CudaDeviceAction *CDA = dyn_cast<CudaDeviceAction>(A)) {
+    os << '"' << CDA->getGpuArchName() << '"' << ", {"
+       << PrintActions1(C, *CDA->begin(), Ids) << "}";
+  } else if (CudaHostAction *CHA = dyn_cast<CudaHostAction>(A)) {
+    os << "{" << PrintActions1(C, *CHA->begin(), Ids) << "}"
+       << ", gpu binaries " << PrintActionList(C, CHA->getDeviceActions(), Ids);
   } else {
-    os << "{";
-    for (Action::iterator it = A->begin(), ie = A->end(); it != ie;) {
-      os << PrintActions1(C, *it, Ids);
-      ++it;
-      if (it != ie)
-        os << ", ";
-    }
-    os << "}";
+    os << PrintActionList(C, A->getInputs(), Ids);
   }
 
   unsigned Id = Ids.size();
   Ids[A] = Id;
   llvm::errs() << Id << ": " << os.str() << ", "
                << types::getTypeName(A->getType()) << "\n";
 
   return Id;
void Driver::BuildInputs(const ToolChain &TC, DerivedArgList &Args,
   if (CCCIsCPP() && Inputs.empty()) {
     // If called as standalone preprocessor, stdin is processed
     // if no other input is present.
     Arg *A = MakeInputArg(Args, Opts, "-");
     Inputs.push_back(std::make_pair(types::TY_C, A));
   }
 }
 
+// For each unique --cuda-gpu-arch= argument creates a TY_CUDA_DEVICE input
+// action and then wraps each in CudaDeviceAction paired with appropriate GPU
+// arch name. If we're only building device-side code, each action remains
+// independent. Otherwise we pass device-side actions as inputs to a new
+// CudaHostAction which combines both host and device side actions.
+static std::unique_ptr<Action>
+buildCudaActions(const Driver &D, const ToolChain &TC, DerivedArgList &Args,
+                 const Arg *InputArg, const types::ID InputType,
+                 std::unique_ptr<Action> Current, ActionList &Actions) {
+
+  assert(InputType == types::TY_CUDA &&
+         "CUDA Actions only apply to CUDA inputs.");
+
+  // Collect all cuda_gpu_arch parameters, removing duplicates.
+  SmallVector<const char *, 4> GpuArchList;
+  llvm::StringSet<> GpuArchNames;
+  for (Arg *A : Args) {
+    if (A->getOption().matches(options::OPT_cuda_gpu_arch_EQ)) {
+      A->claim();
+      if (GpuArchNames.insert(A->getValue()).second)
+        GpuArchList.push_back(A->getValue());
+    }
+  }
+
+  // Default to sm_20 which is the lowest common denominator for supported GPUs.
+  // sm_20 code should work correctly, if suboptimally, on all newer GPUs.
+  if (GpuArchList.empty())
+    GpuArchList.push_back("sm_20");
+
+  // Replicate inputs for each GPU architecture.
+  Driver::InputList CudaDeviceInputs;
+  for (unsigned i = 0, e = GpuArchList.size(); i != e; ++i)
+    CudaDeviceInputs.push_back(std::make_pair(types::TY_CUDA_DEVICE, InputArg));
+
+  // Build actions for all device inputs.
+  ActionList CudaDeviceActions;
+  D.BuildActions(TC, Args, CudaDeviceInputs, CudaDeviceActions);
+  assert(GpuArchList.size() == CudaDeviceActions.size() &&
+         "Failed to create actions for all devices");
+
+  // Check whether any of device actions stopped before they could generate PTX.
+  bool PartialCompilation = false;
+  bool DeviceOnlyCompilation = Args.hasArg(options::OPT_cuda_device_only);
+  for (unsigned i = 0, e = GpuArchList.size(); i != e; ++i) {
+    if (CudaDeviceActions[i]->getKind() != Action::BackendJobClass) {
+      PartialCompilation = true;
+      break;
+    }
+  }
+
+  // Figure out what to do with device actions -- pass them as inputs to the
+  // host action or run each of them independently.
+  if (PartialCompilation || DeviceOnlyCompilation) {
+    // In case of partial or device-only compilation results of device actions
+    // are not consumed by the host action device actions have to be added to
+    // top-level actions list with AtTopLevel=true and run independently.
+
+    // -o is ambiguous if we have more than one top-level action.
+    if (Args.hasArg(options::OPT_o) &&
+        (!DeviceOnlyCompilation || GpuArchList.size() > 1)) {
+      D.Diag(clang::diag::err_drv_output_argument_with_multiple_files);
+      return nullptr;
+    }
+
+    for (unsigned i = 0, e = GpuArchList.size(); i != e; ++i)
+      Actions.push_back(
+          new CudaDeviceAction(std::unique_ptr<Action>(CudaDeviceActions[i]),
+                               GpuArchList[i], /* AtTopLevel */ true));
+    // Kill host action in case of device-only compilation.
+    if (DeviceOnlyCompilation)
+      Current.reset(nullptr);
+    return Current;
+  } else {
+    // Outputs of device actions during complete CUDA compilation get created
+    // with AtTopLevel=false and become inputs for the host action.
+    ActionList DeviceActions;
+    for (unsigned i = 0, e = GpuArchList.size(); i != e; ++i)
+      DeviceActions.push_back(
+          new CudaDeviceAction(std::unique_ptr<Action>(CudaDeviceActions[i]),
+                               GpuArchList[i], /* AtTopLevel */ false));
+    // Return a new host action that incorporates original host action and all
+    // device actions.
+    return std::unique_ptr<Action>(
+        new CudaHostAction(std::move(Current), DeviceActions));
+  }
+}
+
 void Driver::BuildActions(const ToolChain &TC, DerivedArgList &Args,
                           const InputList &Inputs, ActionList &Actions) const {
   llvm::PrettyStackTraceString CrashInfo("Building compilation actions");
 
   if (!SuppressMissingInputWarning && Inputs.empty()) {
     Diag(clang::diag::err_drv_no_input_files);
     return;
   }
if (InitialPhase > FinalPhase) {
           << getPhaseName(InitialPhase)
           << !!FinalPhaseArg
           << (FinalPhaseArg ? FinalPhaseArg->getOption().getName() : "");
       continue;
     }
 
     // Build the pipeline for this file.
     std::unique_ptr<Action> Current(new InputAction(*InputArg, InputType));
-    for (SmallVectorImpl<phases::ID>::iterator
-           i = PL.begin(), e = PL.end(); i != e; ++i) {
+    phases::ID CudaInjectionPhase;
+    if (isSaveTempsEnabled()) {
+      // All phases are done independently, inject GPU blobs during compilation
+      // phase as that's where we generate glue code to init them.
+      CudaInjectionPhase = phases::Compile;
+    } else {
+      // Assumes that clang does everything up until linking phase, so we inject
+      // cuda device actions at the last step before linking. Otherwise CUDA
+      // host action forces preprocessor into a separate invocation.
+      if (FinalPhase == phases::Link) {
+        for (auto i = PL.begin(), e = PL.end(); i != e; ++i) {
+          auto next = i + 1;
+          if (next != e && *next == phases::Link)
+            CudaInjectionPhase = *i;
+        }
+      } else
+        CudaInjectionPhase = FinalPhase;
+    }
+    for (SmallVectorImpl<phases::ID>::iterator i = PL.begin(), e = PL.end();
+         i != e; ++i) {
       phases::ID Phase = *i;
 
       // We are done if this step is past what the user requested.
       if (Phase > FinalPhase)
         break;
 
       // Queue linker inputs.
       if (Phase == phases::Link) {
         assert((i + 1) == e && "linking must be final compilation step.");
         LinkerInputs.push_back(Current.release());
         break;
       }
 
       // Some types skip the assembler phase (e.g., llvm-bc), but we can't
       // encode this in the steps because the intermediate type depends on
       // arguments. Just special case here.
       if (Phase == phases::Assemble && Current->getType() != types::TY_PP_Asm)
         continue;
 
       // Otherwise construct the appropriate action.
       Current = ConstructPhaseAction(TC, Args, Phase, std::move(Current));
+
+      if (InputType == types::TY_CUDA && Phase == CudaInjectionPhase &&
+          !Args.hasArg(options::OPT_cuda_host_only)) {
+        Current = buildCudaActions(*this, TC, Args, InputArg, InputType,
+                                   std::move(Current), Actions);
+        if (!Current)
+          break;
+      }
+
       if (Current->getType() == types::TY_Nothing)
         break;
     }
 
     // If we ended with something, add to the output list.
     if (Current)
       Actions.push_back(Current.release());
   }
static const Tool *SelectToolForJob(Compilation &C, bool SaveTemps,
   }
 
   // A backend job should always be combined with the preceding compile job
   // unless OPT_save_temps is enabled and the compiler is capable of emitting
   // LLVM IR as an intermediate output.
   if (isa<BackendJobAction>(JA)) {
     // Check if the compiler supports emitting LLVM IR.
     assert(Inputs->size() == 1);
-    JobAction *CompileJA = cast<CompileJobAction>(*Inputs->begin());
+    JobAction *CompileJA;
+    // Extract real host action, if it's a CudaHostAction.
+    if (CudaHostAction *CudaHA = dyn_cast<CudaHostAction>(*Inputs->begin()))
+      CompileJA = cast<CompileJobAction>(*CudaHA->begin());
+    else
+      CompileJA = cast<CompileJobAction>(*Inputs->begin());
+
     const Tool *Compiler = TC->SelectTool(*CompileJA);
     if (!Compiler)
       return nullptr;
     if (!Compiler->canEmitIR() || !SaveTemps) {
       Inputs = &(*Inputs)[0]->getInputs();
       ToolForJob = Compiler;
     }
   }
void Driver::BuildJobsForAction(Compilation &C,
                                 const ToolChain *TC,
                                 const char *BoundArch,
                                 bool AtTopLevel,
                                 bool MultipleArchs,
                                 const char *LinkingOutput,
                                 InputInfo &Result) const {
   llvm::PrettyStackTraceString CrashInfo("Building compilation jobs");
 
+  InputInfoList CudaDeviceInputInfos;
+  if (const CudaHostAction *CHA = dyn_cast<CudaHostAction>(A)) {
+    InputInfo II;
+    // Append outputs of device jobs to the input list.
+    for (const Action *DA : CHA->getDeviceActions()) {
+      BuildJobsForAction(C, DA, TC, "", AtTopLevel,
+                         /*MultipleArchs*/ false, LinkingOutput, II);
+      CudaDeviceInputInfos.push_back(II);
+    }
+    // Override current action with a real host compile action and continue
+    // processing it.
+    A = *CHA->begin();
+  }
+
   if (const InputAction *IA = dyn_cast<InputAction>(A)) {
     // FIXME: It would be nice to not claim this here; maybe the old scheme of
     // just using Args was better?
     const Arg &Input = IA->getInputArg();
     Input.claim();
     if (Input.getOption().matches(options::OPT_INPUT)) {
       const char *Name = Input.getValue();
       Result = InputInfo(Name, A->getType(), Name);
     } else
       Result = InputInfo(&Input, A->getType(), "");
     return;
   }
 
   if (const BindArchAction *BAA = dyn_cast<BindArchAction>(A)) {
     const ToolChain *TC;
     const char *ArchName = BAA->getArchName();
 
     if (ArchName)
       TC = &getToolChain(C.getArgs(), ArchName);
     else
       TC = &C.getDefaultToolChain();
 
-    BuildJobsForAction(C, *BAA->begin(), TC, BAA->getArchName(),
-                       AtTopLevel, MultipleArchs, LinkingOutput, Result);
+    BuildJobsForAction(C, *BAA->begin(), TC, ArchName, AtTopLevel,
+                       MultipleArchs, LinkingOutput, Result);
+    return;
+  }
+
+  if (const CudaDeviceAction *CDA = dyn_cast<CudaDeviceAction>(A)) {
+    // Figure out which NVPTX triple to use for device-side compilation based on
+    // whether host is 64-bit.
+    llvm::Triple DeviceTriple(C.getDefaultToolChain().getTriple().isArch64Bit()
+                                  ? "nvptx64-nvidia-cuda"
+                                  : "nvptx-nvidia-cuda");
+    BuildJobsForAction(C, *CDA->begin(),
+                       &getTargetToolChain(C.getArgs(), DeviceTriple),
+                       CDA->getGpuArchName(), CDA->isAtTopLevel(),
+                       /*MultipleArchs*/ true, LinkingOutput, Result);
     return;
   }
 
   const ActionList *Inputs = &A->getInputs();
 
   const JobAction *JA = cast<JobAction>(A);
   const Tool *T = SelectToolForJob(C, isSaveTempsEnabled(), TC, JA, Inputs);
   if (!T)
void Driver::BuildJobsForAction(Compilation &C,
   // Always use the first input as the base input.
   const char *BaseInput = InputInfos[0].getBaseInput();
 
   // ... except dsymutil actions, which use their actual input as the base
   // input.
   if (JA->getType() == types::TY_dSYM)
     BaseInput = InputInfos[0].getFilename();
 
+  // Append outputs of cuda device jobs to the input list
+  if (CudaDeviceInputInfos.size())
+    InputInfos.append(CudaDeviceInputInfos.begin(), CudaDeviceInputInfos.end());
+
   // Determine the place to write output to, if any.
   if (JA->getType() == types::TY_Nothing)
     Result = InputInfo(A->getType(), BaseInput);
   else
     Result = InputInfo(GetNamedOutputPath(C, *JA, BaseInput, BoundArch,
                                           AtTopLevel, MultipleArchs),
                        A->getType(), BaseInput);
 
if (Arg *A = Args.getLastArg(options::OPT_m64, options::OPT_mx32,
 
     if (AT != llvm::Triple::UnknownArch && AT != Target.getArch())
       Target.setArch(AT);
   }
 
   return Target;
 }
 
-const ToolChain &Driver::getToolChain(const ArgList &Args,
-                                      StringRef DarwinArchName) const {
-  llvm::Triple Target = computeTargetTriple(DefaultTargetTriple, Args,
-                                            DarwinArchName);
+const ToolChain &Driver::getTargetToolChain(const ArgList &Args,
+                                            const llvm::Triple &Target) const {
 
   ToolChain *&TC = ToolChains[Target.str()];
   if (!TC) {
     switch (Target.getOS()) {
     case llvm::Triple::CloudABI:
       TC = new toolchains::CloudABI(*this, Target, Args);
       break;
     case llvm::Triple::Darwin:
case llvm::Triple::Win32:
         TC = new toolchains::CrossWindowsToolChain(*this, Target, Args);
         break;
       case llvm::Triple::MSVC:
       case llvm::Triple::UnknownEnvironment:
         TC = new toolchains::MSVCToolChain(*this, Target, Args);
         break;
       }
       break;
+    case llvm::Triple::CUDA:
+      TC = new toolchains::Cuda(*this, Target, Args);
+      break;
     default:
       // TCE is an OSless target
       if (Target.getArchName() == "tce") {
         TC = new toolchains::TCEToolChain(*this, Target, Args);
         break;
       }
       // If Hexagon is configured as an OSless target
       if (Target.getArch() == llvm::Triple::hexagon) {
default:
       }
       TC = new toolchains::Generic_GCC(*this, Target, Args);
       break;
     }
   }
   return *TC;
 }
 
+const ToolChain &Driver::getToolChain(const ArgList &Args,
+                                      StringRef DarwinArchName) const {
+  llvm::Triple Target =
+      computeTargetTriple(DefaultTargetTriple, Args, DarwinArchName);
+  return getTargetToolChain(Args, Target);
+}
+
 bool Driver::ShouldUseClangCompiler(const JobAction &JA) const {
   // Check if user requested no clang, or clang doesn't understand this type (we
   // only handle single inputs for now).
   if (JA.size() != 1 ||
       !types::isAcceptedByClang((*JA.begin())->getType()))
     return false;
 
   // Otherwise make sure this is an action clang understands.

lib/Driver/ToolChain.cpp

Tool *ToolChain::getTool(Action::ActionClass AC) const {
   case Action::AssembleJobClass:
     return getAssemble();
 
   case Action::LinkJobClass:
     return getLink();
 
   case Action::InputClass:
   case Action::BindArchClass:
+  case Action::CudaDeviceClass:
+  case Action::CudaHostClass:
   case Action::LipoJobClass:
   case Action::DsymutilJobClass:
   case Action::VerifyDebugInfoJobClass:
     llvm_unreachable("Invalid tool kind.");
 
   case Action::CompileJobClass:
   case Action::PrecompileJobClass:
   case Action::PreprocessJobClass:

lib/Driver/ToolChains.h

static bool addLibStdCXXIncludePaths(Twine Base, Twine Suffix,
                                        StringRef TargetMultiarchTriple,
                                        Twine IncludeSuffix,
                                        const llvm::opt::ArgList &DriverArgs,
                                        llvm::opt::ArgStringList &CC1Args);
 
   std::string computeSysRoot() const;
 };
 
+class LLVM_LIBRARY_VISIBILITY Cuda : public Linux {
+public:
+  Cuda(const Driver &D, const llvm::Triple &Triple,
+       const llvm::opt::ArgList &Args);
+
+  llvm::opt::DerivedArgList *
+  TranslateArgs(const llvm::opt::DerivedArgList &Args,
+                const char *BoundArch) const override;
+  void addClangTargetOptions(const llvm::opt::ArgList &DriverArgs,
+                             llvm::opt::ArgStringList &CC1Args) const override;
+};
+
 class LLVM_LIBRARY_VISIBILITY Hexagon_TC : public Linux {
 protected:
   GCCVersion GCCLibAndIncVersion;
   Tool *buildAssembler() const override;
   Tool *buildLinker() const override;
 
 public:
   Hexagon_TC(const Driver &D, const llvm::Triple &Triple,

lib/Driver/ToolChains.cpp

 Tool *DragonFly::buildAssembler() const {
   return new tools::dragonfly::Assemble(*this);
 }
 
 Tool *DragonFly::buildLinker() const {
   return new tools::dragonfly::Link(*this);
 }
 
+/// Stub for CUDA toolchain. At the moment we don't have assembler or
+/// linker and need toolchain mainly to propagate device-side options
+/// to CC1.
+
+Cuda::Cuda(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
+    : Linux(D, Triple, Args) {}
+
+void Cuda::addClangTargetOptions(const llvm::opt::ArgList &DriverArgs,
+                                 llvm::opt::ArgStringList &CC1Args) const {
+  Linux::addClangTargetOptions(DriverArgs, CC1Args);
+  CC1Args.push_back("-fcuda-is-device");
+}
+
+llvm::opt::DerivedArgList *
+Cuda::TranslateArgs(const llvm::opt::DerivedArgList &Args,
+                    const char *BoundArch) const {
+  DerivedArgList *DAL = new DerivedArgList(Args.getBaseArgs());
+  const OptTable &Opts = getDriver().getOpts();
+
+  for (Arg *A : Args) {
+    if (A->getOption().matches(options::OPT_Xarch__)) {
+      // Skip this argument unless the architecture matches BoundArch
+      if (A->getValue(0) != StringRef(BoundArch))
+        continue;
+
+      unsigned Index = Args.getBaseArgs().MakeIndex(A->getValue(1));
+      unsigned Prev = Index;
+      std::unique_ptr<Arg> XarchArg(Opts.ParseOneArg(Args, Index));
+
+      // If the argument parsing failed or more than one argument was
+      // consumed, the -Xarch_ argument's parameter tried to consume
+      // extra arguments. Emit an error and ignore.
+      //
+      // We also want to disallow any options which would alter the
+      // driver behavior; that isn't going to work in our model. We
+      // use isDriverOption() as an approximation, although things
+      // like -O4 are going to slip through.
+      if (!XarchArg || Index > Prev + 1) {
+        getDriver().Diag(diag::err_drv_invalid_Xarch_argument_with_args)
+            << A->getAsString(Args);
+        continue;
+      } else if (XarchArg->getOption().hasFlag(options::DriverOption)) {
+        getDriver().Diag(diag::err_drv_invalid_Xarch_argument_isdriver)
+            << A->getAsString(Args);
+        continue;
+      }
+      XarchArg->setBaseArg(A);
+      A = XarchArg.release();
+      DAL->AddSynthesizedArg(A);
+    }
+    DAL->append(A);
+  }
+
+  DAL->AddJoinedArg(nullptr, Opts.getOption(options::OPT_march_EQ), BoundArch);
+  return DAL;
+}
 
 /// XCore tool chain
 XCore::XCore(const Driver &D, const llvm::Triple &Triple,
              const ArgList &Args) : ToolChain(D, Triple, Args) {
   // ProgramPaths are found via 'PATH' environment variable.
 }
 
 Tool *XCore::buildAssembler() const {

lib/Driver/Tools.cpp

static std::string getCPUName(const ArgList &Args, const llvm::Triple &T) {
   case llvm::Triple::mips64:
   case llvm::Triple::mips64el: {
     StringRef CPUName;
     StringRef ABIName;
     mips::getMipsCPUAndABI(Args, T, CPUName, ABIName);
     return CPUName;
   }
 
+  case llvm::Triple::nvptx:
+  case llvm::Triple::nvptx64:
+    if (const Arg *A = Args.getLastArg(options::OPT_march_EQ))
+      return A->getValue();
+    return "";
+
   case llvm::Triple::ppc:
   case llvm::Triple::ppc64:
   case llvm::Triple::ppc64le: {
     std::string TargetCPUName = getPPCTargetCPU(Args);
     // LLVM may default to generating code for the native CPU,
     // but, like gcc, we default to a more generic option for
     // each architecture. (except on Darwin)
     if (TargetCPUName.empty() && !T.isOSDarwin()) {
void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   const Driver &D = getToolChain().getDriver();
   ArgStringList CmdArgs;
 
   bool IsWindowsGNU = getToolChain().getTriple().isWindowsGNUEnvironment();
   bool IsWindowsCygnus =
       getToolChain().getTriple().isWindowsCygwinEnvironment();
   bool IsWindowsMSVC = getToolChain().getTriple().isWindowsMSVCEnvironment();
 
-  assert(Inputs.size() == 1 && "Unable to handle multiple inputs.");
+  // Check number of inputs for sanity. We need at least one input.
+  assert(Inputs.size() >= 1 && "Must have at least one input.");
   const InputInfo &Input = Inputs[0];
+  // CUDA compilation may have multiple inputs (source file + results of
+  // device-side compilations). All other jobs are expected to have exactly one
+  // input.
+  bool IsCuda = types::isCuda(Input.getType());
+  assert((IsCuda || Inputs.size() == 1) && "Unable to handle multiple inputs.");
 
   // Invoke ourselves in -cc1 mode.
   //
   // FIXME: Implement custom jobs for internal actions.
   CmdArgs.push_back("-cc1");
 
   // Add the "effective" target triple.
   CmdArgs.push_back("-triple");
if (Output.getType() == types::TY_Dependencies) {
     // Handled with other dependency code.
   } else if (Output.isFilename()) {
     CmdArgs.push_back("-o");
     CmdArgs.push_back(Output.getFilename());
   } else {
     assert(Output.isNothing() && "Invalid output.");
   }
 
-  for (const auto &II : Inputs) {
-    addDashXForInput(Args, II, CmdArgs);
+  addDashXForInput(Args, Input, CmdArgs);
 
-    if (II.isFilename())
-      CmdArgs.push_back(II.getFilename());
-    else
-      II.getInputArg().renderAsInput(Args, CmdArgs);
-  }
+  if (Input.isFilename())
+    CmdArgs.push_back(Input.getFilename());
+    Input.getInputArg().renderAsInput(Args, CmdArgs);
 
   Args.AddAllArgs(CmdArgs, options::OPT_undef);
 
   const char *Exec = getToolChain().getDriver().getClangProgramPath();
 
   // Optionally embed the -cc1 level arguments into the debug info, for build
   // analysis.
   if (getToolChain().UseDwarfDebugFlags()) {
bool SplitDwarf = Args.hasArg(options::OPT_gsplit_dwarf) &&
      isa<BackendJobAction>(JA));
   const char *SplitDwarfOut;
   if (SplitDwarf) {
     CmdArgs.push_back("-split-dwarf-file");
     SplitDwarfOut = SplitDebugName(Args, Input);
     CmdArgs.push_back(SplitDwarfOut);
   }
 
+  // Host-side cuda compilation receives device-side outputs as Inputs[1...].
+  // Include them with -fcuda-include-gpubinary.
+  if (IsCuda && Inputs.size() > 1)
+    for (InputInfoList::const_iterator it = std::next(Inputs.begin()),
+                                       ie = Inputs.end();
+         it != ie; ++it) {
+      CmdArgs.push_back("-fcuda-include-gpubinary");
+      CmdArgs.push_back(it->getFilename());
+    }
+
   // Finally add the compile command to the compilation.
   if (Args.hasArg(options::OPT__SLASH_fallback) &&
       Output.getType() == types::TY_Object &&
       (InputType == types::TY_C || InputType == types::TY_CXX)) {
     auto CLCommand =
         getCLFallback()->GetCommand(C, JA, Output, Inputs, Args, LinkingOutput);
     C.addCommand(llvm::make_unique<FallbackCommand>(JA, *this, Exec, CmdArgs,
                                                     std::move(CLCommand)));

lib/Driver/Types.cpp

bool types::isAcceptedByClang(ID Id) {
   switch (Id) {
   default:
     return false;
 
   case TY_Asm:
   case TY_C: case TY_PP_C:
   case TY_CL:
   case TY_CUDA: case TY_PP_CUDA:
+  case TY_CUDA_DEVICE:
   case TY_ObjC: case TY_PP_ObjC: case TY_PP_ObjC_Alias:
   case TY_CXX: case TY_PP_CXX:
   case TY_ObjCXX: case TY_PP_ObjCXX: case TY_PP_ObjCXX_Alias:
   case TY_CHeader: case TY_PP_CHeader:
   case TY_CLHeader:
   case TY_ObjCHeader: case TY_PP_ObjCHeader:
   case TY_CXXHeader: case TY_PP_CXXHeader:
   case TY_ObjCXXHeader: case TY_PP_ObjCXXHeader:
bool types::isCXX(ID Id) {
   switch (Id) {
   default:
     return false;
 
   case TY_CXX: case TY_PP_CXX:
   case TY_ObjCXX: case TY_PP_ObjCXX: case TY_PP_ObjCXX_Alias:
   case TY_CXXHeader: case TY_PP_CXXHeader:
   case TY_ObjCXXHeader: case TY_PP_ObjCXXHeader:
-  case TY_CUDA: case TY_PP_CUDA:
+  case TY_CUDA: case TY_PP_CUDA: case TY_CUDA_DEVICE:
+    return true;
+  }
+}
+
+bool types::isCuda(ID Id) {
+  switch (Id) {
+  default:
+    return false;
+
+  case TY_CUDA:
+  case TY_PP_CUDA:
+  case TY_CUDA_DEVICE:
     return true;
   }
 }
 
 types::ID types::lookupTypeForExtension(const char *Ext) {
   return llvm::StringSwitch<types::ID>(Ext)
            .Case("c", TY_C)
            .Case("i", TY_PP_C)
if (Id != TY_Object) {
 
     if (onlyPrecompileType(Id)) {
       P.push_back(phases::Precompile);
     } else {
       if (!onlyAssembleType(Id)) {
         P.push_back(phases::Compile);
         P.push_back(phases::Backend);
       }
+      if (Id != TY_CUDA_DEVICE)
         P.push_back(phases::Assemble);
     }
   }
-  if (!onlyPrecompileType(Id)) {
+
+  if (!onlyPrecompileType(Id) && Id != TY_CUDA_DEVICE) {
     P.push_back(phases::Link);
   }
   assert(0 < P.size() && "Not enough phases in list");
   assert(P.size() <= phases::MaxNumberOfPhases && "Too many phases in list");
   return;
 }
 
 ID types::lookupCXXTypeForCType(ID Id) {

lib/Frontend/CreateInvocationFromCommandLine.cpp

 // Construct a compiler invocation object for command line driver arguments
 //
 //===----------------------------------------------------------------------===//
 
 #include "clang/Frontend/Utils.h"
 #include "clang/Basic/DiagnosticOptions.h"
 #include "clang/Driver/Compilation.h"
 #include "clang/Driver/Driver.h"
+#include "clang/Driver/Action.h"
 #include "clang/Driver/Options.h"
 #include "clang/Driver/Tool.h"
 #include "clang/Frontend/CompilerInstance.h"
 #include "clang/Frontend/FrontendDiagnostic.h"
 #include "llvm/Option/ArgList.h"
 #include "llvm/Support/Host.h"
 using namespace clang;
 using namespace llvm::opt;
clang::createInvocationFromCommandLine(ArrayRef<const char *> ArgList,
 
   // Just print the cc1 options if -### was present.
   if (C->getArgs().hasArg(driver::options::OPT__HASH_HASH_HASH)) {
     C->getJobs().Print(llvm::errs(), "\n", true);
     return nullptr;
   }
 
   // We expect to get back exactly one command job, if we didn't something
-  // failed.
+  // failed. CUDA compilation is an exception as it creates multiple jobs. If
+  // that's the case, we proceed with the first job. If caller needs particular
+  // CUDA job, it should be controlled via --cuda-{host|device}-only option
+  // passed to the driver.
   const driver::JobList &Jobs = C->getJobs();
-  if (Jobs.size() != 1 || !isa<driver::Command>(*Jobs.begin())) {
+  bool CudaCompilation = false;
+  if (Jobs.size() > 1) {
+    for (auto &A : C->getActions())
+      if (isa<driver::CudaDeviceAction>(A)) {
+        CudaCompilation = true;
+        break;
+      }
+  }
+  if (Jobs.size() == 0 || !isa<driver::Command>(*Jobs.begin()) ||
+      (Jobs.size() > 1 && !CudaCompilation)) {
     SmallString<256> Msg;
     llvm::raw_svector_ostream OS(Msg);
     Jobs.Print(OS, "; ", true);
     Diags->Report(diag::err_fe_expected_compiler_job) << OS.str();
     return nullptr;
   }
 
   const driver::Command &Cmd = cast<driver::Command>(*Jobs.begin());

test/Driver/cuda-options.cu

+// Tests CUDA compilation pipeline construction in Driver.
+
+// Simple compilation case:
+// RUN: %clang -### -c %s 2>&1 \
+// Compile device-side to PTX assembly and make sure we use it on the host side.
+// RUN:   | FileCheck -check-prefix CUDA-D1 \
+// Then compile host side and incorporate device code.
+// RUN:   -check-prefix CUDA-H -check-prefix CUDA-H-I1 \
+// Make sure we don't link anything.
+// RUN:   -check-prefix CUDA-NL %s
+
+// Typical compilation + link case:
+// RUN: %clang -### %s 2>&1 \
+// Compile device-side to PTX assembly and make sure we use it on the host side
+// RUN:   | FileCheck -check-prefix CUDA-D1 \
+// Then compile host side and incorporate device code.
+// RUN:   -check-prefix CUDA-H -check-prefix CUDA-H-I1 \
+// Then link things.
+// RUN:   -check-prefix CUDA-L %s
+
+// Verify that -cuda-no-device disables device-side compilation and linking
+// RUN: %clang -### --cuda-host-only %s 2>&1 \
+// Make sure we didn't run device-side compilation.
+// RUN:   | FileCheck -check-prefix CUDA-ND \
+// Then compile host side and make sure we don't attempt to incorporate GPU code.
+// RUN:    -check-prefix CUDA-H -check-prefix CUDA-H-NI \
+// Make sure we don't link anything.
+// RUN:    -check-prefix CUDA-NL %s
+
+// Verify that -cuda-no-host disables host-side compilation and linking
+// RUN: %clang -### --cuda-device-only %s 2>&1 \
+// Compile device-side to PTX assembly
+// RUN:   | FileCheck -check-prefix CUDA-D1 \
+// Make sure there are no host cmpilation or linking.
+// RUN:   -check-prefix CUDA-NH -check-prefix CUDA-NL %s
+
+// Verify that with -S we compile host and device sides to assembly
+// and incorporate device code on the host side.
+// RUN: %clang -### -S -c %s 2>&1 \
+// Compile device-side to PTX assembly
+// RUN:   | FileCheck -check-prefix CUDA-D1 \
+// Then compile host side and incorporate GPU code.
+// RUN:  -check-prefix CUDA-H -check-prefix CUDA-H-I1 \
+// Make sure we don't link anything.
+// RUN:  -check-prefix CUDA-NL %s
+
+// Verify that --cuda-gpu-arch option passes correct GPU
+// archtecture info to device compilation.
+// RUN: %clang -### --cuda-gpu-arch=sm_35 -c %s 2>&1 \
+// Compile device-side to PTX assembly.
+// RUN:   | FileCheck -check-prefix CUDA-D1 -check-prefix CUDA-D1-SM35 \
+// Then compile host side and incorporate GPU code.
+// RUN:   -check-prefix CUDA-H -check-prefix CUDA-H-I1 \
+// Make sure we don't link anything.
+// RUN:   -check-prefix CUDA-NL %s
+
+// Verify that there is device-side compilation per --cuda-gpu-arch args 
+// and that all results are included on the host side.
+// RUN: %clang -### --cuda-gpu-arch=sm_35 --cuda-gpu-arch=sm_30 -c %s 2>&1 \
+// Compile both device-sides to PTX assembly
+// RUN:   | FileCheck \
+// RUN: -check-prefix CUDA-D1 -check-prefix CUDA-D1-SM35 \
+// RUN: -check-prefix CUDA-D2 -check-prefix CUDA-D2-SM30 \
+// Then compile host side and incorporate both device-side outputs
+// RUN:   -check-prefix CUDA-H -check-prefix CUDA-H-I1 -check-prefix CUDA-H-I2 \
+// Make sure we don't link anything.
+// RUN:   -check-prefix CUDA-NL %s
+
+// Match device-side compilation
+// CUDA-D1: "-cc1" "-triple" "nvptx{{64?}}-nvidia-cuda"
+// CUDA-D1-SAME: "-fcuda-is-device"
+// CUDA-D1-SM35-SAME: "-target-cpu" "sm_35"
+// CUDA-D1-SAME: "-o" "[[GPUBINARY1:[^"]*]]"
+// CUDA-D1-SAME: "-x" "cuda"
+
+// Match anothe device-side compilation
+// CUDA-D2: "-cc1" "-triple" "nvptx{{64?}}-nvidia-cuda"
+// CUDA-D2-SAME: "-fcuda-is-device"
+// CUDA-D2-SM30-SAME: "-target-cpu" "sm_30"
+// CUDA-D2-SAME: "-o" "[[GPUBINARY2:[^"]*]]"
+// CUDA-D2-SAME: "-x" "cuda"
+
+// Match no device-side compilation
+// CUDA-ND-NOT: "-cc1" "-triple" "nvptx{{64?}}-nvidia-cuda"
+// CUDA-ND-SAME-NOT: "-fcuda-is-device"
+
+// Match host-side compilation
+// CUDA-H: "-cc1" "-triple" 
+// CUDA-H-SAME-NOT: "nvptx{{64?}}-nvidia-cuda"
+// CUDA-H-SAME-NOT: "-fcuda-is-device"
+// CUDA-H-SAME: "-o" "[[HOSTOBJ:[^"]*]]"
+// CUDA-H-SAME: "-x" "cuda"
+// CUDA-H-I1-SAME: "-fcuda-include-gpubinary" "[[GPUBINARY1]]"
+// CUDA-H-I2-SAME: "-fcuda-include-gpubinary" "[[GPUBINARY2]]"
+
+// Match no GPU code inclusion.
+// CUDA-H-NI-NOT: "-fcuda-include-gpubinary"
+
+// Match no CUDA compilation
+// CUDA-NH-NOT: "-cc1" "-triple"
+// CUDA-NH-SAME-NOT: "-x" "cuda"
+
+// Match linker
+// CUDA-L: "{{.*}}ld{{(.exe)?}}"
+// CUDA-L-SAME: "[[HOSTOBJ]]"
+
+// Match no linker
+// CUDA-NL-NOT: "{{.*}}ld{{(.exe)?}}"

test/Index/attributes-cuda.cu

-// RUN: c-index-test -test-load-source all -x cuda %s | FileCheck %s
-
+// RUN: c-index-test -test-load-source all -x cuda -nocudainc --cuda-host-only %s | FileCheck %s
+// RUN: c-index-test -test-load-source all -x cuda -nocudainc --cuda-device-only %s | FileCheck %s
 __attribute__((device)) void f_device();
 __attribute__((global)) void f_global();
 __attribute__((constant)) int* g_constant;
 __attribute__((shared)) float *g_shared;
 __attribute__((host)) void f_host();
 
 // CHECK:       attributes-cuda.cu:3:30: FunctionDecl=f_device:3:30
 // CHECK-NEXT:  attributes-cuda.cu:3:16: attribute(device)
 // CHECK:       attributes-cuda.cu:4:30: FunctionDecl=f_global:4:30
 // CHECK-NEXT:  attributes-cuda.cu:4:16: attribute(global)
 // CHECK:       attributes-cuda.cu:5:32: VarDecl=g_constant:5:32 (Definition)
 // CHECK-NEXT:  attributes-cuda.cu:5:16: attribute(constant)
 // CHECK:       attributes-cuda.cu:6:32: VarDecl=g_shared:6:32 (Definition)
 // CHECK-NEXT:  attributes-cuda.cu:6:16: attribute(shared)
 // CHECK:       attributes-cuda.cu:7:28: FunctionDecl=f_host:7:28
 // CHECK-NEXT:  attributes-cuda.cu:7:16: attribute(host)

test/Index/index-file.cu

+// Make sure we can process CUDA file even if driver creates multiple jobs
+// RUN: c-index-test -test-load-source all %s | FileCheck %s -check-prefix=CHECK-ANY
+// Make sure we process correct side of cuda compilation
+// RUN: c-index-test -test-load-source all --cuda-host-only %s | FileCheck %s -check-prefix=CHECK-HOST
+// RUN: c-index-test -test-load-source all --cuda-device-only %s | FileCheck %s -check-prefix=CHECK-DEVICE
+
+// CHECK-ANY: macro definition=__cplusplus
+// CHECK-HOST-NOT: macro definition=__CUDA_ARCH__
+// CHECK-DEVICE: macro definition=__CUDA_ARCH__

tools/libclang/CIndex.cpp

std::unique_ptr<ASTUnit> Unit(ASTUnit::LoadFromCommandLine(
       Args->data(), Args->data() + Args->size(), Diags,
       CXXIdx->getClangResourcesPath(), CXXIdx->getOnlyLocalDecls(),
       /*CaptureDiagnostics=*/true, *RemappedFiles.get(),
       /*RemappedFilesKeepOriginalName=*/true, PrecompilePreamble, TUKind,
       CacheCodeCompletionResults, IncludeBriefCommentsInCodeCompletion,
       /*AllowPCHWithCompilerErrors=*/true, SkipFunctionBodies,
       /*UserFilesAreVolatile=*/true, ForSerialization, &ErrUnit));
 
+  // Early failures in LoadFromCommandLine may return with ErrUnit unset.
+  if (!Unit && !ErrUnit) {
+    PTUI->result = CXError_ASTReadError;
+    return;
+  }
+
   if (NumErrors != Diags->getClient()->getNumErrors()) {
     // Make sure to check that 'Unit' is non-NULL.
     if (CXXIdx->getDisplayDiagnostics())
       printDiagsToStderr(Unit ? Unit.get() : ErrUnit.get());
   }
 
   if (isASTReadError(Unit ? Unit.get() : ErrUnit.get())) {
     PTUI->result = CXError_ASTReadError;

unittests/ASTMatchers/ASTMatchersTest.h

testing::AssertionResult matchesConditionallyWithCuda(
   if (!Finder.addDynamicMatcher(AMatcher, &VerifyDynamicFound))
     return testing::AssertionFailure() << "Could not add dynamic matcher";
   std::unique_ptr<FrontendActionFactory> Factory(
       newFrontendActionFactory(&Finder));
   // Some tests use typeof, which is a gnu extension.
   std::vector<std::string> Args;
   Args.push_back("-xcuda");
   Args.push_back("-fno-ms-extensions");
+  Args.push_back("--cuda-host-only");
   Args.push_back(CompileArg);
   if (!runToolOnCodeWithArgs(Factory->create(),
                              CudaHeader + Code, Args)) {
     return testing::AssertionFailure() << "Parsing error in \"" << Code << "\"";
   }
   if (Found != DynamicFound) {
     return testing::AssertionFailure() << "Dynamic match result ("
                                        << DynamicFound