[SYCL] Implement device library linking for runtime compilation (#15810)

Mimics `clang::driver::tools::SYCL::getDeviceLibraries` assuming a
SPIR-V target (= no AoT, no third-party GPUs, no native CPU).

Same as for the compilation step, warning/error reporting is still
rudimentary and will be improved in a future PR.

---------

Signed-off-by: Julian Oppermann <[email protected]>

Author: jopperm

sycl-jit/jit-compiler/CMakeLists.txt

@@ -19,10 +19,12 @@ add_llvm_library(sycl-jit
    BitReader
    Core
    Support
+   Option
    Analysis
    IPO
    TransformUtils
    Passes
+   IRReader
    Linker
    ScalarOpts
    InstCombine

sycl-jit/jit-compiler/lib/KernelFusion.cpp

@@ -237,22 +237,30 @@ fuseKernels(View<SYCLKernelInfo> KernelInformation, const char *FusedKernelName,
 extern "C" KF_EXPORT_SYMBOL JITResult
 compileSYCL(InMemoryFile SourceFile, View<InMemoryFile> IncludeFiles,
             View<const char *> UserArgs) {
-  auto ModuleOrErr = compileDeviceCode(SourceFile, IncludeFiles, UserArgs);
+  auto UserArgListOrErr = parseUserArgs(UserArgs);
+  if (!UserArgListOrErr) {
+    return errorToFusionResult(UserArgListOrErr.takeError(),
+                               "Parsing of user arguments failed");
+  }
+  llvm::opt::InputArgList UserArgList = std::move(*UserArgListOrErr);
+
+  auto ModuleOrErr = compileDeviceCode(SourceFile, IncludeFiles, UserArgList);
   if (!ModuleOrErr) {
     return errorToFusionResult(ModuleOrErr.takeError(),
                                "Device compilation failed");
   }
-  std::unique_ptr<llvm::Module> Module = std::move(*ModuleOrErr);
 
-  SYCLKernelInfo Kernel;
-  auto Error = translation::KernelTranslator::translateKernel(
-      Kernel, *Module, JITContext::getInstance(), BinaryFormat::SPIRV);
+  std::unique_ptr<llvm::LLVMContext> Context;
+  std::unique_ptr<llvm::Module> Module = std::move(*ModuleOrErr);
+  Context.reset(&Module->getContext());
 
-  auto *LLVMCtx = &Module->getContext();
-  Module.reset();
-  delete LLVMCtx;
+  if (auto Error = linkDeviceLibraries(*Module, UserArgList)) {
+    return errorToFusionResult(std::move(Error), "Device linking failed");
+  }
 
-  if (Error) {
+  SYCLKernelInfo Kernel;
+  if (auto Error = translation::KernelTranslator::translateKernel(
+          Kernel, *Module, JITContext::getInstance(), BinaryFormat::SPIRV)) {
     return errorToFusionResult(std::move(Error), "SPIR-V translation failed");
   }
 

sycl-jit/jit-compiler/lib/rtc/DeviceCompilation.cpp

@@ -8,13 +8,28 @@
 
 #include "DeviceCompilation.h"
 
+#include <clang/Basic/DiagnosticDriver.h>
 #include <clang/Basic/Version.h>
 #include <clang/CodeGen/CodeGenAction.h>
 #include <clang/Driver/Compilation.h>
+#include <clang/Driver/Options.h>
 #include <clang/Frontend/CompilerInstance.h>
+#include <clang/Frontend/TextDiagnosticBuffer.h>
 #include <clang/Tooling/CompilationDatabase.h>
 #include <clang/Tooling/Tooling.h>
 
+#include <llvm/IRReader/IRReader.h>
+#include <llvm/Linker/Linker.h>
+
+#include <array>
+
+using namespace clang;
+using namespace clang::tooling;
+using namespace clang::driver;
+using namespace clang::driver::options;
+using namespace llvm;
+using namespace llvm::opt;
+
 #ifdef _GNU_SOURCE
 #include <dlfcn.h>
 static char X; // Dummy symbol, used as an anchor for `dlinfo` below.
@@ -96,9 +111,6 @@ static const std::string &getDPCPPRoot() {
 }
 
 namespace {
-using namespace clang;
-using namespace clang::tooling;
-using namespace clang::driver;
 
 struct GetLLVMModuleAction : public ToolAction {
   // Code adapted from `FrontendActionFactory::runInvocation`.
@@ -143,23 +155,37 @@ struct GetLLVMModuleAction : public ToolAction {
 
 } // anonymous namespace
 
-llvm::Expected<std::unique_ptr<llvm::Module>>
+Expected<std::unique_ptr<llvm::Module>>
 jit_compiler::compileDeviceCode(InMemoryFile SourceFile,
                                 View<InMemoryFile> IncludeFiles,
-                                View<const char *> UserArgs) {
+                                const InputArgList &UserArgList) {
   const std::string &DPCPPRoot = getDPCPPRoot();
   if (DPCPPRoot == InvalidDPCPPRoot) {
-    return llvm::createStringError("Could not locate DPCPP root directory");
+    return createStringError("Could not locate DPCPP root directory");
   }
 
-  SmallVector<std::string> CommandLine = {"-fsycl-device-only"};
-  // TODO: Allow instrumentation again when device library linking is
-  //       implemented.
-  CommandLine.push_back("-fno-sycl-instrument-device-code");
-  CommandLine.append(UserArgs.begin(), UserArgs.end());
-  clang::tooling::FixedCompilationDatabase DB{".", CommandLine};
+  DerivedArgList DAL{UserArgList};
+  const auto &OptTable = getDriverOptTable();
+  DAL.AddFlagArg(nullptr, OptTable.getOption(OPT_fsycl_device_only));
+  DAL.AddJoinedArg(
+      nullptr, OptTable.getOption(OPT_resource_dir_EQ),
+      (DPCPPRoot + "/lib/clang/" + Twine(CLANG_VERSION_MAJOR)).str());
+  for (auto *Arg : UserArgList) {
+    DAL.append(Arg);
+  }
+  // Remove args that will trigger an unused command line argument warning for
+  // the FrontendAction invocation, but are handled later (e.g. during device
+  // linking).
+  DAL.eraseArg(OPT_fsycl_device_lib_EQ);
+  DAL.eraseArg(OPT_fno_sycl_device_lib_EQ);
+
+  SmallVector<std::string> CommandLine;
+  for (auto *Arg : DAL) {
+    CommandLine.emplace_back(Arg->getAsString(DAL));
+  }
 
-  clang::tooling::ClangTool Tool{DB, {SourceFile.Path}};
+  FixedCompilationDatabase DB{".", CommandLine};
+  ClangTool Tool{DB, {SourceFile.Path}};
 
   // Set up in-memory filesystem.
   Tool.mapVirtualFile(SourceFile.Path, SourceFile.Contents);
@@ -170,17 +196,14 @@ jit_compiler::compileDeviceCode(InMemoryFile SourceFile,
   // Reset argument adjusters to drop the `-fsyntax-only` flag which is added by
   // default by this API.
   Tool.clearArgumentsAdjusters();
-  // Then, modify argv[0] and set the resource directory so that the driver
-  // picks up the correct SYCL environment.
+  // Then, modify argv[0] so that the driver picks up the correct SYCL
+  // environment. We've already set the resource directory above.
   Tool.appendArgumentsAdjuster(
       [&DPCPPRoot](const CommandLineArguments &Args,
                    StringRef Filename) -> CommandLineArguments {
         (void)Filename;
         CommandLineArguments NewArgs = Args;
         NewArgs[0] = (Twine(DPCPPRoot) + "/bin/clang++").str();
-        NewArgs.push_back((Twine("-resource-dir=") + DPCPPRoot + "/lib/clang/" +
-                           Twine(CLANG_VERSION_MAJOR))
-                              .str());
         return NewArgs;
       });
 
@@ -190,5 +213,202 @@ jit_compiler::compileDeviceCode(InMemoryFile SourceFile,
   }
 
   // TODO: Capture compiler errors from the ClangTool.
-  return llvm::createStringError("Unable to obtain LLVM module");
+  return createStringError("Unable to obtain LLVM module");
+}
+
+// This function is a simplified copy of the device library selection process in
+// `clang::driver::tools::SYCL::getDeviceLibraries`, assuming a SPIR-V target
+// (no AoT, no third-party GPUs, no native CPU). Keep in sync!
+static SmallVector<std::string, 8>
+getDeviceLibraries(const ArgList &Args, DiagnosticsEngine &Diags) {
+  struct DeviceLibOptInfo {
+    StringRef DeviceLibName;
+    StringRef DeviceLibOption;
+  };
+
+  // Currently, all SYCL device libraries will be linked by default.
+  llvm::StringMap<bool> DeviceLibLinkInfo = {
+      {"libc", true},          {"libm-fp32", true},   {"libm-fp64", true},
+      {"libimf-fp32", true},   {"libimf-fp64", true}, {"libimf-bf16", true},
+      {"libm-bfloat16", true}, {"internal", true}};
+
+  // If -fno-sycl-device-lib is specified, its values will be used to exclude
+  // linkage of libraries specified by DeviceLibLinkInfo. Linkage of "internal"
+  // libraries cannot be affected via -fno-sycl-device-lib.
+  bool ExcludeDeviceLibs = false;
+
+  if (Arg *A = Args.getLastArg(OPT_fsycl_device_lib_EQ,
+                               OPT_fno_sycl_device_lib_EQ)) {
+    if (A->getValues().size() == 0) {
+      Diags.Report(diag::warn_drv_empty_joined_argument)
+          << A->getAsString(Args);
+    } else {
+      if (A->getOption().matches(OPT_fno_sycl_device_lib_EQ)) {
+        ExcludeDeviceLibs = true;
+      }
+
+      for (StringRef Val : A->getValues()) {
+        if (Val == "all") {
+          for (const auto &K : DeviceLibLinkInfo.keys()) {
+            DeviceLibLinkInfo[K] = (K == "internal") || !ExcludeDeviceLibs;
+          }
+          break;
+        }
+        auto LinkInfoIter = DeviceLibLinkInfo.find(Val);
+        if (LinkInfoIter == DeviceLibLinkInfo.end() || Val == "internal") {
+          Diags.Report(diag::err_drv_unsupported_option_argument)
+              << A->getSpelling() << Val;
+        }
+        DeviceLibLinkInfo[Val] = !ExcludeDeviceLibs;
+      }
+    }
+  }
+
+  using SYCLDeviceLibsList = SmallVector<DeviceLibOptInfo, 5>;
+
+  const SYCLDeviceLibsList SYCLDeviceWrapperLibs = {
+      {"libsycl-crt", "libc"},
+      {"libsycl-complex", "libm-fp32"},
+      {"libsycl-complex-fp64", "libm-fp64"},
+      {"libsycl-cmath", "libm-fp32"},
+      {"libsycl-cmath-fp64", "libm-fp64"},
+      {"libsycl-imf", "libimf-fp32"},
+      {"libsycl-imf-fp64", "libimf-fp64"},
+      {"libsycl-imf-bf16", "libimf-bf16"}};
+  // ITT annotation libraries are linked in separately whenever the device
+  // code instrumentation is enabled.
+  const SYCLDeviceLibsList SYCLDeviceAnnotationLibs = {
+      {"libsycl-itt-user-wrappers", "internal"},
+      {"libsycl-itt-compiler-wrappers", "internal"},
+      {"libsycl-itt-stubs", "internal"}};
+
+  SmallVector<std::string, 8> LibraryList;
+  StringRef LibSuffix = ".bc";
+  auto AddLibraries = [&](const SYCLDeviceLibsList &LibsList) {
+    for (const DeviceLibOptInfo &Lib : LibsList) {
+      if (!DeviceLibLinkInfo[Lib.DeviceLibOption]) {
+        continue;
+      }
+      SmallString<128> LibName(Lib.DeviceLibName);
+      llvm::sys::path::replace_extension(LibName, LibSuffix);
+      LibraryList.push_back(Args.MakeArgString(LibName));
+    }
+  };
+
+  AddLibraries(SYCLDeviceWrapperLibs);
+
+  if (Args.hasFlag(OPT_fsycl_instrument_device_code,
+                   OPT_fno_sycl_instrument_device_code, false)) {
+    AddLibraries(SYCLDeviceAnnotationLibs);
+  }
+
+  return LibraryList;
+}
+
+Error jit_compiler::linkDeviceLibraries(llvm::Module &Module,
+                                        const InputArgList &UserArgList) {
+  const std::string &DPCPPRoot = getDPCPPRoot();
+  if (DPCPPRoot == InvalidDPCPPRoot) {
+    return createStringError("Could not locate DPCPP root directory");
+  }
+
+  // TODO: Seems a bit excessive to set up this machinery for one warning and
+  //       one error. Rethink when implementing the build log/error reporting as
+  //       mandated by the extension.
+  IntrusiveRefCntPtr<DiagnosticIDs> DiagID{new DiagnosticIDs};
+  IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts{new DiagnosticOptions};
+  TextDiagnosticBuffer *DiagBuffer = new TextDiagnosticBuffer;
+  DiagnosticsEngine Diags(DiagID, DiagOpts, DiagBuffer);
+
+  auto LibNames = getDeviceLibraries(UserArgList, Diags);
+  if (std::distance(DiagBuffer->err_begin(), DiagBuffer->err_end()) > 0) {
+    std::string DiagMsg;
+    raw_string_ostream SOS{DiagMsg};
+    interleave(
+        DiagBuffer->err_begin(), DiagBuffer->err_end(),
+        [&](const auto &D) { SOS << D.second; }, [&]() { SOS << '\n'; });
+    return createStringError("Could not determine list of device libraries: %s",
+                             DiagMsg.c_str());
+  }
+  // TODO: Add warnings to build log.
+
+  LLVMContext &Context = Module.getContext();
+  for (const std::string &LibName : LibNames) {
+    std::string LibPath = DPCPPRoot + "/lib/" + LibName;
+
+    SMDiagnostic Diag;
+    std::unique_ptr<llvm::Module> Lib = parseIRFile(LibPath, Diag, Context);
+    if (!Lib) {
+      std::string DiagMsg;
+      raw_string_ostream SOS(DiagMsg);
+      Diag.print(/*ProgName=*/nullptr, SOS);
+      return createStringError(DiagMsg);
+    }
+
+    if (Linker::linkModules(Module, std::move(Lib), Linker::LinkOnlyNeeded)) {
+      // TODO: Obtain detailed error message from the context's diagnostics
+      //       handler.
+      return createStringError("Unable to link device library: %s",
+                               LibPath.c_str());
+    }
+  }
+
+  return Error::success();
+}
+
+Expected<InputArgList>
+jit_compiler::parseUserArgs(View<const char *> UserArgs) {
+  unsigned MissingArgIndex, MissingArgCount;
+  auto UserArgsRef = UserArgs.to<ArrayRef>();
+  auto AL = getDriverOptTable().ParseArgs(UserArgsRef, MissingArgIndex,
+                                          MissingArgCount);
+  if (MissingArgCount) {
+    return createStringError(
+        "User option '%s' at index %d is missing an argument",
+        UserArgsRef[MissingArgIndex], MissingArgIndex);
+  }
+
+  // Check for unsupported options.
+  // TODO: There are probably more, e.g. requesting non-SPIR-V targets.
+  {
+    // -fsanitize=address
+    bool IsDeviceAsanEnabled = false;
+    if (Arg *A = AL.getLastArg(OPT_fsanitize_EQ, OPT_fno_sanitize_EQ)) {
+      if (A->getOption().matches(OPT_fsanitize_EQ) &&
+          A->getValues().size() == 1) {
+        std::string SanitizeVal = A->getValue();
+        IsDeviceAsanEnabled = SanitizeVal == "address";
+      }
+    } else {
+      // User can pass -fsanitize=address to device compiler via
+      // -Xsycl-target-frontend.
+      auto SyclFEArg = AL.getAllArgValues(OPT_Xsycl_frontend);
+      IsDeviceAsanEnabled = (std::count(SyclFEArg.begin(), SyclFEArg.end(),
+                                        "-fsanitize=address") > 0);
+      if (!IsDeviceAsanEnabled) {
+        auto SyclFEArgEq = AL.getAllArgValues(OPT_Xsycl_frontend_EQ);
+        IsDeviceAsanEnabled =
+            (std::count(SyclFEArgEq.begin(), SyclFEArgEq.end(),
+                        "-fsanitize=address") > 0);
+      }
+
+      // User can also enable asan for SYCL device via -Xarch_device option.
+      if (!IsDeviceAsanEnabled) {
+        auto DeviceArchVals = AL.getAllArgValues(OPT_Xarch_device);
+        for (auto DArchVal : DeviceArchVals) {
+          if (DArchVal.find("-fsanitize=address") != std::string::npos) {
+            IsDeviceAsanEnabled = true;
+            break;
+          }
+        }
+      }
+    }
+
+    if (IsDeviceAsanEnabled) {
+      return createStringError(
+          "Device ASAN is not supported for runtime compilation");
+    }
+  }
+
+  return Expected<InputArgList>{std::move(AL)};
 }

sycl-jit/jit-compiler/lib/rtc/DeviceCompilation.h

@@ -13,6 +13,7 @@
 #include "View.h"
 
 #include <llvm/IR/Module.h>
+#include <llvm/Option/ArgList.h>
 #include <llvm/Support/Error.h>
 
 #include <memory>
@@ -21,7 +22,13 @@ namespace jit_compiler {
 
 llvm::Expected<std::unique_ptr<llvm::Module>>
 compileDeviceCode(InMemoryFile SourceFile, View<InMemoryFile> IncludeFiles,
-                  View<const char *> UserArgs);
+                  const llvm::opt::InputArgList &UserArgList);
+
+llvm::Error linkDeviceLibraries(llvm::Module &Module,
+                                const llvm::opt::InputArgList &UserArgList);
+
+llvm::Expected<llvm::opt::InputArgList>
+parseUserArgs(View<const char *> UserArgs);
 
 } // namespace jit_compiler