[CUDA][HIP] Add -fuse-cuid

[yaxunl]

Summary

This patch added a distinct CUID for each input file, which is represented by InputAction.
clang initially creates an InputAction for each input file for the host compilation. In CUDA/HIP action
builder, each InputAction is given a CUID and cloned for each GPU arch, and the CUID is also cloned. In this way,
we guarantee the corresponding device and host compilation for the same file shared the
same CUID. On the other hand, different compilation units have different CUID.

-fuse-cuid=random|hash|none is added to control the method to generate CUID. The default
is hash. -cuid=X is also added to specify CUID explicitly, which overrides -fuse-cuid.

This patch is separated from https://reviews.llvm.org/D85223

[JonChesterfield]

@jdoerfert this may be a candidate for deriving names of extracted target regions

[JonChesterfield]

clang/lib/Frontend/CompilerInvocation.cpp

2746

Why this limitation? In particular I can imagine people using an id based on a filesystem location, which introduces /\:. and possibly other characters.

[tra]

clang/lib/Frontend/CompilerInvocation.cpp

2746

I guess one of the reasons is that CUID is used to create unique externally visible symbol names, so the charset is sort of the lowest common denominator that could be directly used in the symbol name.

We could work around that by accepting an arbitrary string as a CUID and then using its hash to create unique stable suffix.

[yaxunl]

clang/lib/Frontend/CompilerInvocation.cpp

2746

will remove the check and use hash for suffix.

[yaxunl]

Revised by Jon and Artem's comments. Removed check of CUID value.

[tra]

Few test nits. LGTM in principle.

clang/test/Driver/hip-cuid.hip

99

Is it necessary? The next 'RUN' command would overwrite the temp file anyways.
Also, you don't have to call all temporary files %t.out. You could use %t-1.out, etc and leave the cleanup to the test driver.

101–103

Putting RUN down in the test file makes them easy to miss. Maybe these should be in their own hip-cuid-rdc.hip test structured in a conventional way -- RUN lines first, followed by checks.

[yaxunl]

clang/test/Driver/hip-cuid.hip

99

will remove rm.

101–103

will split the test

[MaskRay]

Should -cuid= be --cuid=?

[yaxunl]

In D95007#2638955, @MaskRay wrote:

Should -cuid= be --cuid=?

For the existing clang options, there seem to be no rule or convention whether to use - or --. For example,

-rtlib=<value>          Compiler runtime library to use
-save-stats=<value>     Save llvm statistics.
-save-temps=<value>     Save intermediate compilation results.
-std=<value>            Language standard to compile for
-stdlib=<value>         C++ standard library to use
-struct-layout=<value>  Run the Structure Peeling passes
-struct-peel-mem-block-size=<value>
-struct-peel-ptr-size=<value>
-sycl-std=<value>       SYCL language standard to compile for.

Here I choose -cuid= since it is shorter.

clang/include/clang/Basic/LangOptions.h

public:
   /// Triples of the OpenMP targets that the host code codegen should
   /// take into account in order to generate accurate offloading descriptors.
   std::vector<llvm::Triple> OMPTargetTriples;
 
   /// Name of the IR file that contains the result of the OpenMP target
   /// host code generation.
   std::string OMPHostIRFile;
 
+  /// The user provided compilation unit ID, if non-empty. This is used to
+  /// externalize static variables which is needed to support accessing static
+  /// device variables in host code for single source offloading languages
+  /// like CUDA/HIP.
+  std::string CUID;
+
   /// Indicates whether the front-end is explicitly told that the
   /// input is a header file (i.e. -x c-header).
   bool IsHeaderFile = false;
 
   LangOptions();
 
   // Define accessors/mutators for language options of enumeration type.
 #define LANGOPT(Name, Bits, Default, Description)

clang/include/clang/Driver/Action.h

public:
   }
   bool isOffloading(OffloadKind OKind) const {
     return isHostOffloading(OKind) || isDeviceOffloading(OKind);
   }
 };
 
 class InputAction : public Action {
   const llvm::opt::Arg &Input;
-
+  std::string Id;
   virtual void anchor();
 
 public:
-  InputAction(const llvm::opt::Arg &Input, types::ID Type);
+  InputAction(const llvm::opt::Arg &Input, types::ID Type,
+              StringRef Id = StringRef());
 
   const llvm::opt::Arg &getInputArg() const { return Input; }
 
+  void setId(StringRef _Id) { Id = _Id.str(); }
+  StringRef getId() const { return Id; }
+
   static bool classof(const Action *A) {
     return A->getKind() == InputClass;
   }
 };
 
 class BindArchAction : public Action {
   virtual void anchor();
 

clang/include/clang/Driver/Options.td

 def gpu_max_threads_per_block_EQ : Joined<["--"], "gpu-max-threads-per-block=">,
   Flags<[CC1Option]>,
   HelpText<"Default max threads per block for kernel launch bounds for HIP">,
   MarshallingInfoStringInt<LangOpts<"GPUMaxThreadsPerBlock">, "256">,
   ShouldParseIf<hip.KeyPath>;
 def gpu_instrument_lib_EQ : Joined<["--"], "gpu-instrument-lib=">,
   HelpText<"Instrument device library for HIP, which is a LLVM bitcode containing "
   "__cyg_profile_func_enter and __cyg_profile_func_exit">;
+def cuid_EQ : Joined<["-"], "cuid=">, Flags<[CC1Option]>,
+  HelpText<"An ID for compilation unit, which should be the same for the same "
+           "compilation unit but different for different compilation units. "
+           "It is used to externalize device-side static variables for single "
+           "source offloading languages CUDA and HIP so that they can be "
+           "accessed by the host code of the same compilation unit.">;
+def fuse_cuid_EQ : Joined<["-"], "fuse-cuid=">,
+  HelpText<"Method to generate ID's for compilation units for single source "
+           "offloading languages CUDA and HIP: 'hash' (ID's generated by hashing "
+           "file path and command line options) | 'random' (ID's generated as "
+           "random numbers) | 'none' (disabled). Default is 'hash'. This option "
+           "will be overriden by option '-cuid=[ID]' if it is specified." >;
 def libomptarget_nvptx_bc_path_EQ : Joined<["--"], "libomptarget-nvptx-bc-path=">, Group<i_Group>,
   HelpText<"Path to libomptarget-nvptx bitcode library">;
 def dD : Flag<["-"], "dD">, Group<d_Group>, Flags<[CC1Option]>,
   HelpText<"Print macro definitions in -E mode in addition to normal output">;
 def dI : Flag<["-"], "dI">, Group<d_Group>, Flags<[CC1Option]>,
   HelpText<"Print include directives in -E mode in addition to normal output">,
   MarshallingInfoFlag<PreprocessorOutputOpts<"ShowIncludeDirectives">>;
 def dM : Flag<["-"], "dM">, Group<d_Group>, Flags<[CC1Option]>,

clang/lib/Driver/Action.cpp

case OFK_HIP:
     // TODO: Add other programming models here.
   }
 
   llvm_unreachable("invalid offload kind");
 }
 
 void InputAction::anchor() {}
 
-InputAction::InputAction(const Arg &_Input, types::ID _Type)
-    : Action(InputClass, _Type), Input(_Input) {}
+InputAction::InputAction(const Arg &_Input, types::ID _Type, StringRef _Id)
+    : Action(InputClass, _Type), Input(_Input), Id(_Id.str()) {}
 
 void BindArchAction::anchor() {}
 
 BindArchAction::BindArchAction(Action *Input, StringRef ArchName)
     : Action(BindArchClass, Input), ArchName(ArchName) {}
 
 void OffloadAction::anchor() {}
 

clang/lib/Driver/Driver.cpp

 #include "llvm/Option/OptTable.h"
 #include "llvm/Option/Option.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/ErrorHandling.h"
 #include "llvm/Support/ExitCodes.h"
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/FormatVariadic.h"
 #include "llvm/Support/Host.h"
+#include "llvm/Support/MD5.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/PrettyStackTrace.h"
 #include "llvm/Support/Process.h"
 #include "llvm/Support/Program.h"
 #include "llvm/Support/StringSaver.h"
 #include "llvm/Support/TargetRegistry.h"
 #include "llvm/Support/VirtualFileSystem.h"
 #include "llvm/Support/raw_ostream.h"
protected:
     bool IsActive = false;
 
     /// Flag for -fgpu-rdc.
     bool Relocatable = false;
 
     /// Default GPU architecture if there's no one specified.
     CudaArch DefaultCudaArch = CudaArch::UNKNOWN;
 
+    /// Method to generate compilation unit ID specified by option
+    /// '-fuse-cuid='.
+    enum UseCUIDKind { CUID_Hash, CUID_Random, CUID_None, CUID_Invalid };
+    UseCUIDKind UseCUID = CUID_Hash;
+
+    /// Compilation unit ID specified by option '-cuid='.
+    StringRef FixedCUID;
+
   public:
     CudaActionBuilderBase(Compilation &C, DerivedArgList &Args,
                           const Driver::InputList &Inputs,
                           Action::OffloadKind OFKind)
         : DeviceActionBuilder(C, Args, Inputs, OFKind) {}
 
     ActionBuilderReturnCode addDeviceDepences(Action *HostAction) override {
       // While generating code for CUDA, we only depend on the host input action
ActionBuilderReturnCode addDeviceDepences(Action *HostAction) override {
         IsActive = true;
 
         if (CompileHostOnly)
           return ABRT_Success;
 
         // Replicate inputs for each GPU architecture.
         auto Ty = IA->getType() == types::TY_HIP ? types::TY_HIP_DEVICE
                                                  : types::TY_CUDA_DEVICE;
+        std::string CUID = FixedCUID.str();
+        if (CUID.empty()) {
+          if (UseCUID == CUID_Random)
+            CUID = llvm::utohexstr(llvm::sys::Process::GetRandomNumber(),
+                                   /*LowerCase=*/true);
+          else if (UseCUID == CUID_Hash) {
+            llvm::MD5 Hasher;
+            llvm::MD5::MD5Result Hash;
+            SmallString<256> RealPath;
+            llvm::sys::fs::real_path(IA->getInputArg().getValue(), RealPath,
+                                     /*expand_tilde=*/true);
+            Hasher.update(RealPath);
+            for (auto *A : Args) {
+              if (A->getOption().matches(options::OPT_INPUT))
+                continue;
+              Hasher.update(A->getAsString(Args));
+            }
+            Hasher.final(Hash);
+            CUID = llvm::utohexstr(Hash.low(), /*LowerCase=*/true);
+          }
+        }
+        IA->setId(CUID);
+
         for (unsigned I = 0, E = GpuArchList.size(); I != E; ++I) {
           CudaDeviceActions.push_back(
-              C.MakeAction<InputAction>(IA->getInputArg(), Ty));
+              C.MakeAction<InputAction>(IA->getInputArg(), Ty, IA->getId()));
         }
 
         return ABRT_Success;
       }
 
       // If this is an unbundling action use it as is for each CUDA toolchain.
       if (auto *UA = dyn_cast<OffloadUnbundlingJobAction>(HostAction)) {
 
bool initialize() override {
       CompileHostOnly = PartialCompilationArg &&
                         PartialCompilationArg->getOption().matches(
                             options::OPT_cuda_host_only);
       CompileDeviceOnly = PartialCompilationArg &&
                           PartialCompilationArg->getOption().matches(
                               options::OPT_cuda_device_only);
       EmitLLVM = Args.getLastArg(options::OPT_emit_llvm);
       EmitAsm = Args.getLastArg(options::OPT_S);
+      FixedCUID = Args.getLastArgValue(options::OPT_cuid_EQ);
+      if (Arg *A = Args.getLastArg(options::OPT_fuse_cuid_EQ)) {
+        StringRef UseCUIDStr = A->getValue();
+        UseCUID = llvm::StringSwitch<UseCUIDKind>(UseCUIDStr)
+                      .Case("hash", CUID_Hash)
+                      .Case("random", CUID_Random)
+                      .Case("none", CUID_None)
+                      .Default(CUID_Invalid);
+        if (UseCUID == CUID_Invalid) {
+          C.getDriver().Diag(diag::err_drv_invalid_value)
+              << A->getAsString(Args) << UseCUIDStr;
+          C.setContainsError();
+          return true;
+        }
+      }
 
       // Collect all cuda_gpu_arch parameters, removing duplicates.
       std::set<StringRef> GpuArchs;
       bool Error = false;
       for (Arg *A : Args) {
         if (!(A->getOption().matches(options::OPT_offload_arch_EQ) ||
               A->getOption().matches(options::OPT_no_offload_arch_EQ)))
           continue;

clang/lib/Driver/ToolChains/Clang.cpp

   }
 
   if (IsCuda) {
     if (Args.hasFlag(options::OPT_fcuda_short_ptr,
                      options::OPT_fno_cuda_short_ptr, false))
       CmdArgs.push_back("-fcuda-short-ptr");
   }
 
+  if (IsCuda || IsHIP) {
+    // Determine the original source input.
+    const Action *SourceAction = &JA;
+    while (SourceAction->getKind() != Action::InputClass) {
+      assert(!SourceAction->getInputs().empty() && "unexpected root action!");
+      SourceAction = SourceAction->getInputs()[0];
+    }
+    auto CUID = cast<InputAction>(SourceAction)->getId();
+    if (!CUID.empty())
+      CmdArgs.push_back(Args.MakeArgString(Twine("-cuid=") + Twine(CUID)));
+  }
+
   if (IsHIP)
     CmdArgs.push_back("-fcuda-allow-variadic-functions");
 
   // OpenMP offloading device jobs take the argument -fopenmp-host-ir-file-path
   // to specify the result of the compile phase on the host, so the meaningful
   // device declarations can be identified. Also, -fopenmp-is-device is passed
   // along to tell the frontend that it is generating code for a device, so that
   // only the relevant declarations are emitted.

clang/lib/Frontend/CompilerInvocation.cpp

#undef LANG_OPTION_WITH_MARSHALLING
 
   if (const Arg *A = Args.getLastArg(OPT_fcf_protection_EQ)) {
     StringRef Name = A->getValue();
     if (Name == "full" || Name == "branch") {
       Opts.CFProtectionBranch = 1;
     }
   }
 
+
+  if (auto *A = Args.getLastArg(OPT_cuid_EQ)) {
+    Opts.CUID = std::string(A->getValue());
+  }
+
   if (Opts.ObjC) {
     if (Arg *arg = Args.getLastArg(OPT_fobjc_runtime_EQ)) {
       StringRef value = arg->getValue();
       if (Opts.ObjCRuntime.tryParse(value))
         Diags.Report(diag::err_drv_unknown_objc_runtime) << value;
     }
 
     if (Args.hasArg(OPT_fobjc_gc_only))

clang/test/Driver/hip-cuid-hash.hip

+// REQUIRES: clang-driver
+// REQUIRES: x86-registered-target
+// REQUIRES: amdgpu-registered-target
+
+// Check CUID generated by hash.
+// The same CUID is generated for the same file with the same options.
+
+// RUN: %clang -### -x hip -target x86_64-unknown-linux-gnu \
+// RUN:   --offload-arch=gfx906 -c -nogpulib -fuse-cuid=hash \
+// RUN:   %S/Inputs/hip_multiple_inputs/a.cu >%t.out 2>&1
+
+// RUN: %clang -### -x hip -target x86_64-unknown-linux-gnu \
+// RUN:   --offload-arch=gfx906 -c -nogpulib -fuse-cuid=hash \
+// RUN:   %S/Inputs/hip_multiple_inputs/a.cu >>%t.out 2>&1
+
+// RUN: FileCheck %s -check-prefixes=SAME -input-file %t.out
+
+// Check CUID generated by hash.
+// Different CUID's are generated for the same file with different options.
+
+// RUN: %clang -### -x hip -target x86_64-unknown-linux-gnu -DX=1 \
+// RUN:   --offload-arch=gfx906 -c -nogpulib -fuse-cuid=hash \
+// RUN:   %S/Inputs/hip_multiple_inputs/a.cu >%t.out 2>&1
+
+// RUN: %clang -### -x hip -target x86_64-unknown-linux-gnu -DX=2 \
+// RUN:   --offload-arch=gfx906 -c -nogpulib -fuse-cuid=hash \
+// RUN:   %S/Inputs/../Inputs/hip_multiple_inputs/a.cu >>%t.out 2>&1
+
+// RUN: FileCheck %s -check-prefixes=DIFF -input-file %t.out
+
+// SAME: "{{.*}}clang{{.*}}" {{.*}} "-target-cpu" "gfx906" {{.*}}"-cuid=[[CUID:[0-9a-f]+]]"
+// SAME: "{{.*}}clang{{.*}}" {{.*}} "-target-cpu" "gfx906" {{.*}}"-cuid=[[CUID]]"
+
+// DIFF: "{{.*}}clang{{.*}}" {{.*}} "-target-cpu" "gfx906" {{.*}}"-cuid=[[CUID:[0-9a-f]+]]"
+// DIFF-NOT: "{{.*}}clang{{.*}}" {{.*}} "-target-cpu" "gfx906" {{.*}}"-cuid=[[CUID]]"

clang/test/Driver/hip-cuid.hip

+// REQUIRES: clang-driver
+// REQUIRES: x86-registered-target
+// REQUIRES: amdgpu-registered-target
+
+// Check invalid -fuse-cuid= option.
+
+// RUN: not %clang -### -x hip \
+// RUN:   -target x86_64-unknown-linux-gnu \
+// RUN:   --offload-arch=gfx900 \
+// RUN:   --offload-arch=gfx906 \
+// RUN:   -c -nogpulib -fuse-cuid=invalid \
+// RUN:   %S/Inputs/hip_multiple_inputs/a.cu \
+// RUN:   %S/Inputs/hip_multiple_inputs/b.hip \
+// RUN: 2>&1 | FileCheck -check-prefixes=INVALID %s
+
+// Check random CUID generator.
+
+// RUN: %clang -### -x hip \
+// RUN:   -target x86_64-unknown-linux-gnu \
+// RUN:   --offload-arch=gfx900 \
+// RUN:   --offload-arch=gfx906 \
+// RUN:   -c -nogpulib -fuse-cuid=random \
+// RUN:   %S/Inputs/hip_multiple_inputs/a.cu \
+// RUN:   %S/Inputs/hip_multiple_inputs/b.hip \
+// RUN: 2>&1 | FileCheck -check-prefixes=COMMON,HEX %s
+
+// Check fixed CUID.
+
+// RUN: %clang -### -x hip \
+// RUN:   -target x86_64-unknown-linux-gnu \
+// RUN:   --offload-arch=gfx900 \
+// RUN:   --offload-arch=gfx906 \
+// RUN:   -c -nogpulib -cuid=xyz_123 \
+// RUN:   %S/Inputs/hip_multiple_inputs/a.cu \
+// RUN:   %S/Inputs/hip_multiple_inputs/b.hip \
+// RUN: 2>&1 | FileCheck -check-prefixes=COMMON,FIXED %s
+
+// Check fixed CUID override -fuse-cuid.
+
+// RUN: %clang -### -x hip \
+// RUN:   -target x86_64-unknown-linux-gnu \
+// RUN:   --offload-arch=gfx900 \
+// RUN:   --offload-arch=gfx906 \
+// RUN:   -c -nogpulib -fuse-cuid=random -cuid=xyz_123 \
+// RUN:   %S/Inputs/hip_multiple_inputs/a.cu \
+// RUN:   %S/Inputs/hip_multiple_inputs/b.hip \
+// RUN: 2>&1 | FileCheck -check-prefixes=COMMON,FIXED %s
+
+// Check hash CUID generator.
+
+// RUN: %clang -### -x hip \
+// RUN:   -target x86_64-unknown-linux-gnu \
+// RUN:   --offload-arch=gfx900 \
+// RUN:   --offload-arch=gfx906 \
+// RUN:   -c -nogpulib -fuse-cuid=hash \
+// RUN:   %S/Inputs/hip_multiple_inputs/a.cu \
+// RUN:   %S/Inputs/hip_multiple_inputs/b.hip \
+// RUN: 2>&1 | FileCheck -check-prefixes=COMMON,HEX %s
+
+// INVALID: invalid value 'invalid' in '-fuse-cuid=invalid'
+
+// COMMON: "{{.*}}clang{{.*}}" "-cc1"{{.*}} "-triple" "amdgcn-amd-amdhsa"
+// COMMON-SAME: "-target-cpu" "gfx900"
+// HEX-SAME: "-cuid=[[CUID:[0-9a-f]+]]"
+// FIXED-SAME: "-cuid=[[CUID:xyz_123]]"
+// COMMON-SAME: "{{.*}}a.cu"
+
+// COMMON: "{{.*}}clang{{.*}}" "-cc1"{{.*}} "-triple" "amdgcn-amd-amdhsa"
+// COMMON-SAME: "-target-cpu" "gfx906"
+// COMMON-SAME: "-cuid=[[CUID]]"
+// COMMON-SAME: "{{.*}}a.cu"
+
+// COMMON: "{{.*}}clang{{.*}}" "-cc1"{{.*}} "-triple" "x86_64-unknown-linux-gnu"
+// COMMON-SAME: "-cuid=[[CUID]]"
+// COMMON-SAME: "{{.*}}a.cu"
+
+// COMMON: "{{.*}}clang{{.*}}" "-cc1"{{.*}} "-triple" "amdgcn-amd-amdhsa"
+// COMMON-SAME: "-target-cpu" "gfx900"
+// HEX-NOT: "-cuid=[[CUID]]"
+// HEX-SAME: "-cuid=[[CUID2:[0-9a-f]+]]"
+// FIXED-SAME: "-cuid=[[CUID2:xyz_123]]"
+// COMMON-SAME: "{{.*}}b.hip"
+
+// COMMON: "{{.*}}clang{{.*}}" "-cc1"{{.*}} "-triple" "amdgcn-amd-amdhsa"
+// COMMON-SAME: "-target-cpu" "gfx906"
+// HEX-NOT: "-cuid=[[CUID]]"
+// COMMON-SAME: "-cuid=[[CUID2]]"
+// COMMON-SAME: "{{.*}}b.hip"
+
+// COMMON: "{{.*}}clang{{.*}}" "-cc1"{{.*}} "-triple" "x86_64-unknown-linux-gnu"
+// HEX-NOT: "-cuid=[[CUID]]"
+// COMMON-SAME: "-cuid=[[CUID2]]"
+// COMMON-SAME: "{{.*}}b.hip"