Commit 6e82d0df authored by Sergey Dmitriev's avatar Sergey Dmitriev
Browse files

[Clang][Bundler] Add 'exclude' flag to target objects sections 

Summary: This flag tells link editor to exclude section from linker inputs when linking executable or shared library.

Reviewers: ABataev, alexshap, jdoerfert

Reviewed By: ABataev

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D73408
parent 4b04e117

clang/test/Driver/clang-offload-bundler.c

+2 −1
Original line number Diff line number Diff line
@@ -253,7 +253,8 @@ 


// RUN: clang-offload-bundler -type=o -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -inputs=%t.o,%t.tgt1,%t.tgt2 -outputs=%t.bundle3.o -### 2>&1 \

// RUN: | FileCheck %s -DHOST=%itanium_abi_triple -DINOBJ1=%t.o -DINOBJ2=%t.tgt1 -DINOBJ3=%t.tgt2 -DOUTOBJ=%t.bundle3.o --check-prefix CK-OBJ-CMD

// CK-OBJ-CMD: llvm-objcopy{{(.exe)?}}" "--add-section=__CLANG_OFFLOAD_BUNDLE__host-[[HOST]]=[[INOBJ1]]" "--add-section=__CLANG_OFFLOAD_BUNDLE__openmp-powerpc64le-ibm-linux-gnu=[[INOBJ2]]" "--add-section=__CLANG_OFFLOAD_BUNDLE__openmp-x86_64-pc-linux-gnu=[[INOBJ3]]" "[[INOBJ1]]" "[[OUTOBJ]]"

// CK-OBJ-CMD: llvm-objcopy{{(.exe)?}}" "--add-section=__CLANG_OFFLOAD_BUNDLE__host-[[HOST]]=[[INOBJ1]]" "--add-section=__CLANG_OFFLOAD_BUNDLE__openmp-powerpc64le-ibm-linux-gnu=[[INOBJ2]]" "--add-section=__CLANG_OFFLOAD_BUNDLE__openmp-x86_64-pc-linux-gnu=[[INOBJ3]]" "[[INOBJ1]]" "[[TEMPOBJ:.*]]"

// CK-OBJ-CMD: llvm-objcopy{{(.exe)?}}" "--set-section-flags=__CLANG_OFFLOAD_BUNDLE__host-[[HOST]]=readonly,exclude" "--set-section-flags=__CLANG_OFFLOAD_BUNDLE__openmp-powerpc64le-ibm-linux-gnu=readonly,exclude" "--set-section-flags=__CLANG_OFFLOAD_BUNDLE__openmp-x86_64-pc-linux-gnu=readonly,exclude" "[[TEMPOBJ]]" "[[OUTOBJ]]"



// RUN: clang-offload-bundler -type=o -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -inputs=%t.o,%t.tgt1,%t.tgt2 -outputs=%t.bundle3.o

// RUN: clang-offload-bundler -type=o -targets=host-%itanium_abi_triple,openmp-powerpc64le-ibm-linux-gnu,openmp-x86_64-pc-linux-gnu -outputs=%t.res.o,%t.res.tgt1,%t.res.tgt2 -inputs=%t.bundle3.o -unbundle

clang/tools/clang-offload-bundler/ClangOffloadBundler.cpp

+48 −11
Original line number Diff line number Diff line
@@ -30,6 +30,7 @@ 
#include "llvm/Support/Error.h"

#include "llvm/Support/ErrorOr.h"

#include "llvm/Support/FileSystem.h"

#include "llvm/Support/FileUtilities.h"

#include "llvm/Support/MemoryBuffer.h"

#include "llvm/Support/Path.h"

#include "llvm/Support/Program.h"
@@ -463,6 +464,15 @@ public: 
    if (NumberOfProcessedInputs != NumberOfInputs)

      return Error::success();



    // We will use llvm-objcopy to add target objects sections to the output

    // fat object. These sections should have 'exclude' flag set which tells

    // link editor to remove them from linker inputs when linking executable or

    // shared library. llvm-objcopy currently does not support adding new

    // section and changing flags for the added section in one invocation, and

    // because of that we have to run it two times. First run adds sections and

    // the second changes flags.

    // TODO: change it to one run once llvm-objcopy starts supporting that.



    // Find llvm-objcopy in order to create the bundle binary.

    ErrorOr<std::string> Objcopy = sys::findProgramByName(

        "llvm-objcopy", sys::path::parent_path(BundlerExecutable));
@@ -476,7 +486,15 @@ public: 
    // to pass down to llvm-objcopy.

    OS.close();



    // Compose command line for the objcopy tool.

    // Create an intermediate temporary file to save object after the first

    // llvm-objcopy run.

    SmallString<128u> IntermediateObj;

    if (std::error_code EC = sys::fs::createTemporaryFile(

            "clang-offload-bundler", "tmp", IntermediateObj))

      return createFileError(IntermediateObj, EC);

    FileRemover IntermediateObjRemover(IntermediateObj);



    // Compose llvm-objcopy command line for add target objects' sections.

    BumpPtrAllocator Alloc;

    StringSaver SS{Alloc};

    SmallVector<StringRef, 8u> ObjcopyArgs{"llvm-objcopy"};
@@ -485,25 +503,44 @@ public: 
                                    OFFLOAD_BUNDLER_MAGIC_STR + TargetNames[I] +

                                    "=" + InputFileNames[I]));

    ObjcopyArgs.push_back(InputFileNames[HostInputIndex]);

    ObjcopyArgs.push_back(IntermediateObj);



    if (Error Err = executeObjcopy(*Objcopy, ObjcopyArgs))

      return Err;



    // And run llvm-objcopy for the second time to update section flags.

    ObjcopyArgs.resize(1);

    for (unsigned I = 0; I < NumberOfInputs; ++I)

      ObjcopyArgs.push_back(SS.save(Twine("--set-section-flags=") +

                                    OFFLOAD_BUNDLER_MAGIC_STR + TargetNames[I] +

                                    "=readonly,exclude"));

    ObjcopyArgs.push_back(IntermediateObj);

    ObjcopyArgs.push_back(OutputFileNames.front());



    // If the user asked for the commands to be printed out, we do that instead

    // of executing it.

    if (Error Err = executeObjcopy(*Objcopy, ObjcopyArgs))

      return Err;



    return Error::success();

  }



  Error WriteBundle(raw_fd_ostream &OS, MemoryBuffer &Input) final {

    return Error::success();

  }



private:

  static Error executeObjcopy(StringRef Objcopy, ArrayRef<StringRef> Args) {

    // If the user asked for the commands to be printed out, we do that

    // instead of executing it.

    if (PrintExternalCommands) {

      errs() << "\"" << *Objcopy << "\"";

      for (StringRef Arg : drop_begin(ObjcopyArgs, 1))

      errs() << "\"" << Objcopy << "\"";

      for (StringRef Arg : drop_begin(Args, 1))

        errs() << " \"" << Arg << "\"";

      errs() << "\n";

    } else {

      if (sys::ExecuteAndWait(*Objcopy, ObjcopyArgs))

      if (sys::ExecuteAndWait(Objcopy, Args))

        return createStringError(inconvertibleErrorCode(),

                                 "'llvm-objcopy' tool failed");

    }



    return Error::success();

  }



  Error WriteBundle(raw_fd_ostream &OS, MemoryBuffer &Input) final {

    return Error::success();

  }

};