[SYCL] Add offload wrapping for SYCL kind.

clang/test/Driver/linker-wrapper-image.c

@@ -1,6 +1,7 @@
 // REQUIRES: x86-registered-target
 // REQUIRES: nvptx-registered-target
 // REQUIRES: amdgpu-registered-target
+// REQUIRES: spirv-registered-target
 
 // RUN: %clang -cc1 %s -triple x86_64-unknown-linux-gnu -emit-obj -o %t.elf.o
 
@@ -263,3 +264,38 @@
 //      HIP: while.end:
 // HIP-NEXT:   ret void
 // HIP-NEXT: }
+
+// RUN: clang-offload-packager -o %t.out --image=file=%t.elf.o,kind=sycl,triple=spirv64-unknown-unknown,arch=generic
+// RUN: %clang -cc1 %s -triple x86_64-unknown-linux-gnu -emit-obj -o %t.o \
+// RUN:   -fembed-offload-object=%t.out
+// RUN: clang-linker-wrapper --print-wrapped-module --dry-run --host-triple=x86_64-unknown-linux-gnu \
+// RUN:   --linker-path=/usr/bin/ld %t.o -o a.out 2>&1 | FileCheck %s --check-prefixes=SYCL
+// RUN: clang-linker-wrapper --print-wrapped-module --dry-run --host-triple=x86_64-unknown-linux-gnu -r \
+// RUN:   --linker-path=/usr/bin/ld %t.o -o a.out 2>&1 | FileCheck %s --check-prefixes=SYCL
+
+//      SYCL: %__sycl.tgt_device_image = type { i16, i8, i8, ptr, ptr, ptr, ptr, ptr, ptr, ptr, ptr, ptr }
+// SYCL-NEXT: %__sycl.tgt_bin_desc = type { i16, i16, ptr, ptr, ptr }
+
+//      SYCL: @.sycl_offloading.target.0 = internal unnamed_addr constant [1 x i8] zeroinitializer
+// SYCL-NEXT: @.sycl_offloading.opts.compile.0 = internal unnamed_addr constant [1 x i8] zeroinitializer
+// SYCL-NEXT: @.sycl_offloading.opts.link.0 = internal unnamed_addr constant [1 x i8] zeroinitializer
+// SYCL-NEXT: @.sycl_offloading.0.data = internal unnamed_addr constant [0 x i8] zeroinitializer
+// SYCL-NEXT: @__sycl_offload_entries_arr = internal constant [0 x %struct.__tgt_offload_entry] zeroinitializer
+// SYCL-NEXT: @.sycl_offloading.0.info = internal local_unnamed_addr constant [2 x i64] [i64 ptrtoint (ptr @.sycl_offloading.0.data to i64), i64 0], section ".tgtimg", align 16
+// SYCL-NEXT: @llvm.used = appending global [1 x ptr] [ptr @.sycl_offloading.0.info], section "llvm.metadata"
+// SYCL-NEXT: @.sycl_offloading.device_images = internal unnamed_addr constant [1 x %__sycl.tgt_device_image] [%__sycl.tgt_device_image { i16 3, i8 8, i8 0, ptr @.sycl_offloading.target.0, ptr @.sycl_offloading.opts.compile.0, ptr @.sycl_offloading.opts.link.0, ptr @.sycl_offloading.0.data, ptr @.sycl_offloading.0.data, ptr @__sycl_offload_entries_arr, ptr @__sycl_offload_entries_arr, ptr null, ptr null }]
+// SYCL-NEXT: @.sycl_offloading.descriptor = internal constant %__sycl.tgt_bin_desc { i16 1, i16 1, ptr @.sycl_offloading.device_images, ptr null, ptr null }
+// SYCL-NEXT: @llvm.global_ctors = appending global [1 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 1, ptr @sycl.descriptor_reg, ptr null }]
+// SYCL-NEXT: @llvm.global_dtors = appending global [1 x { i32, ptr, ptr }] [{ i32, ptr, ptr } { i32 1, ptr @sycl.descriptor_unreg, ptr null }]
+
+//      SYCL: define internal void @sycl.descriptor_reg() section ".text.startup" {
+// SYCL-NEXT: entry:
+// SYCL-NEXT:   call void @__sycl_register_lib(ptr @.sycl_offloading.descriptor)
+// SYCL-NEXT:   ret void
+// SYCL-NEXT: }
+
+//      SYCL: define internal void @sycl.descriptor_unreg() section ".text.startup" {
+// SYCL-NEXT: entry:
+// SYCL-NEXT:   call void @__sycl_unregister_lib(ptr @.sycl_offloading.descriptor)
+// SYCL-NEXT:   ret void
+// SYCL-NEXT: }

clang/test/Driver/linker-wrapper.c

@@ -54,7 +54,7 @@ __attribute__((visibility("protected"), used)) int x;
 // RUN: clang-offload-packager -o %t.out \
 // RUN:   --image=file=%t.spirv.bc,kind=sycl,triple=spirv64-unknown-unknown,arch=generic
 // RUN: %clang -cc1 %s -triple x86_64-unknown-linux-gnu -emit-obj -o %t.o -fembed-offload-object=%t.out
-// RUN: not clang-linker-wrapper --host-triple=x86_64-unknown-linux-gnu --dry-run \
+// RUN: clang-linker-wrapper --host-triple=x86_64-unknown-linux-gnu --dry-run \
 // RUN:   --linker-path=/usr/bin/ld %t.o -o a.out 2>&1 | FileCheck %s --check-prefix=SPIRV-LINK
 
 // SPIRV-LINK: clang{{.*}} -o {{.*}}.img -dumpdir a.out.spirv64..img. --target=spirv64-unknown-unknown {{.*}}.o --sycl-link -Xlinker -triple=spirv64-unknown-unknown -Xlinker -arch=

clang/tools/clang-linker-wrapper/ClangLinkerWrapper.cpp

@@ -717,6 +717,14 @@ wrapDeviceImages(ArrayRef<std::unique_ptr<MemoryBuffer>> Buffers,
             M, BuffersToWrap.front(), offloading::getOffloadEntryArray(M)))
       return std::move(Err);
     break;
+  case OFK_SYCL: {
+    // TODO: fill these options once the Driver supports them.
+    offloading::SYCLWrappingOptions WrappingOptions;
+    if (Error Err =
+            offloading::wrapSYCLBinaries(M, BuffersToWrap, WrappingOptions))
+      return std::move(Err);
+    break;
+  }
   default:
     return createStringError(getOffloadKindName(Kind) +
                              " wrapping is not supported");
@@ -754,6 +762,36 @@ bundleOpenMP(ArrayRef<OffloadingImage> Images) {
   return std::move(Buffers);
 }
 
+Expected<SmallVector<std::unique_ptr<MemoryBuffer>>>
+bundleSYCL(ArrayRef<OffloadingImage> Images) {
+  SmallVector<std::unique_ptr<MemoryBuffer>> Buffers;
+  if (DryRun) {
+    // In dry-run mode there is an empty input which is insufficient for
+    // the testing. Therefore, we insert a stub value.
+    OffloadBinary::OffloadingImage Image;
+    Image.TheOffloadKind = OffloadKind::OFK_SYCL;
+    Image.Image = MemoryBuffer::getMemBufferCopy("");
+    SmallString<0> SerializedImage = OffloadBinary::write(Image);
+    Buffers.emplace_back(MemoryBuffer::getMemBufferCopy(SerializedImage));
+    return Buffers;
+  }
+
+  for (const OffloadingImage &TheImage : Images) {
+    SmallVector<OffloadFile> OffloadBinaries;
+    if (Error E = extractOffloadBinaries(*TheImage.Image, OffloadBinaries))
+      return E;
+
+    for (const OffloadFile &File : OffloadBinaries) {
+      const OffloadBinary &Binary = *File.getBinary();
+      SmallString<0> SerializedImage =
+          OffloadBinary::write(Binary.getOffloadingImage());
+      Buffers.emplace_back(MemoryBuffer::getMemBufferCopy(SerializedImage));
+    }
+  }
+
+  return Buffers;
+}
+
 Expected<SmallVector<std::unique_ptr<MemoryBuffer>>>
 bundleCuda(ArrayRef<OffloadingImage> Images, const ArgList &Args) {
   SmallVector<std::pair<StringRef, StringRef>, 4> InputFiles;
@@ -806,8 +844,9 @@ bundleLinkedOutput(ArrayRef<OffloadingImage> Images, const ArgList &Args,
   llvm::TimeTraceScope TimeScope("Bundle linked output");
   switch (Kind) {
   case OFK_OpenMP:
-  case OFK_SYCL:
     return bundleOpenMP(Images);
+  case OFK_SYCL:
+    return bundleSYCL(Images);
   case OFK_Cuda:
     return bundleCuda(Images, Args);
   case OFK_HIP:

llvm/include/llvm/Frontend/Offloading/OffloadWrapper.h

@@ -13,6 +13,8 @@
 #include "llvm/IR/Module.h"
 #include "llvm/Support/Compiler.h"
 
+#include <string>
+
 namespace llvm {
 namespace offloading {
 using EntryArrayTy = std::pair<GlobalVariable *, GlobalVariable *>;
@@ -52,6 +54,23 @@ LLVM_ABI llvm::Error wrapHIPBinary(llvm::Module &M, llvm::ArrayRef<char> Images,
                                    EntryArrayTy EntryArray,
                                    llvm::StringRef Suffix = "",
                                    bool EmitSurfacesAndTextures = true);
+
+struct SYCLWrappingOptions {
+  // Target/compiler specific options that are suggested to use to "compile"
+  // program at runtime.
+  std::string CompileOptions;
+  // Target/compiler specific options that are suggested to use to "link"
+  // program at runtime.
+  std::string LinkOptions;
+};
+
+/// Wraps OffloadBinaries in the given \p Buffers into the module \p M
+/// as global symbols and registers the images with the SYCL Runtime.
+/// \param Options Settings that allows to turn on optional data and settings.
+llvm::Error LLVM_ABI
+wrapSYCLBinaries(llvm::Module &M, llvm::ArrayRef<llvm::ArrayRef<char>> Buffers,
+                 SYCLWrappingOptions Options = SYCLWrappingOptions());
+
 } // namespace offloading
 } // namespace llvm
 

llvm/include/llvm/Frontend/Offloading/Utility.h

@@ -82,7 +82,8 @@ LLVM_ABI StructType *getEntryTy(Module &M);
 /// \param Data Extra data storage associated with the entry.
 /// \param SectionName The section this entry will be placed at.
 /// \param AuxAddr An extra pointer if needed.
-LLVM_ABI void
+/// \return The emitted global variable containing the offloading entry.
+LLVM_ABI GlobalVariable *
 emitOffloadingEntry(Module &M, object::OffloadKind Kind, Constant *Addr,
                     StringRef Name, uint64_t Size, uint32_t Flags,
                     uint64_t Data, Constant *AuxAddr = nullptr,

llvm/include/llvm/Object/OffloadBinary.h

@@ -48,6 +48,7 @@ enum ImageKind : uint16_t {
   IMG_Cubin,
   IMG_Fatbinary,
   IMG_PTX,
+  IMG_SPIRV,
   IMG_LAST,
 };
 
@@ -70,9 +71,9 @@ class OffloadBinary : public Binary {
 
   /// The offloading metadata that will be serialized to a memory buffer.
   struct OffloadingImage {
-    ImageKind TheImageKind;
-    OffloadKind TheOffloadKind;
-    uint32_t Flags;
+    ImageKind TheImageKind = ImageKind::IMG_None;
+    OffloadKind TheOffloadKind = OffloadKind::OFK_None;
+    uint32_t Flags = 0;
     MapVector<StringRef, StringRef> StringData;
     std::unique_ptr<MemoryBuffer> Image;
   };
@@ -84,6 +85,8 @@ class OffloadBinary : public Binary {
   /// Serialize the contents of \p File to a binary buffer to be read later.
   LLVM_ABI static SmallString<0> write(const OffloadingImage &);
 
+  OffloadingImage getOffloadingImage() const;
+
   static uint64_t getAlignment() { return 8; }
 
   ImageKind getImageKind() const { return TheEntry->TheImageKind; }