.uleb128 .LBB_END0_1-.LBB0_1 # BB_1 size
.byte y # BB_1 metadata
+``SHT_LLVM_OFFLOADING`` Section (offloading data)
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+This section stores the binary data used to perform offloading device linking
+and execution, creating a fat binary. This section is emitted during compilation
+of offloading languages such as OpenMP or CUDA. If the data is intended to be
+used by the device linker only, it should use the ``SHF_EXCLUDE`` flag so it is
+automatically stripped from the final executable or shared library.
+
+The binary data stored in this section conforms to a custom binary format used
+for storing offloading metadata. This format is effectively a string table
+containing metadata accompanied by a device image.
+
CodeView-Dependent
------------------
// backward-compatibility).
SHT_LLVM_CALL_GRAPH_PROFILE = 0x6fff4c09, // LLVM Call Graph Profile.
SHT_LLVM_BB_ADDR_MAP = 0x6fff4c0a, // LLVM Basic Block Address Map.
+ SHT_LLVM_OFFLOADING = 0x6fff4c0b, // LLVM device offloading data.
// Android's experimental support for SHT_RELR sections.
// https://android.googlesource.com/platform/bionic/+/b7feec74547f84559a1467aca02708ff61346d2a/libc/include/elf.h#512
SHT_ANDROID_RELR = 0x6fffff00, // Relocation entries; only offsets.
if (hasPrefix(Name, ".preinit_array"))
return ELF::SHT_PREINIT_ARRAY;
+ if (hasPrefix(Name, ".llvm.offloading"))
+ return ELF::SHT_LLVM_OFFLOADING;
+
if (K.isBSS() || K.isThreadBSS())
return ELF::SHT_NOBITS;
Type = ELF::SHT_LLVM_SYMPART;
else if (TypeName == "llvm_bb_addr_map")
Type = ELF::SHT_LLVM_BB_ADDR_MAP;
+ else if (TypeName == "llvm_offloading")
+ Type = ELF::SHT_LLVM_OFFLOADING;
else if (TypeName.getAsInteger(0, Type))
return TokError("unknown section type");
}
OS << "llvm_bb_addr_map";
else if (Type == ELF::SHT_LLVM_BB_ADDR_MAP_V0)
OS << "llvm_bb_addr_map_v0";
+ else if (Type == ELF::SHT_LLVM_OFFLOADING)
+ OS << "llvm_offloading";
else
report_fatal_error("unsupported type 0x" + Twine::utohexstr(Type) +
" for section " + getName());
STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_PART_PHDR);
STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_BB_ADDR_MAP_V0);
STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_BB_ADDR_MAP);
+ STRINGIFY_ENUM_CASE(ELF, SHT_LLVM_OFFLOADING);
STRINGIFY_ENUM_CASE(ELF, SHT_GNU_ATTRIBUTES);
STRINGIFY_ENUM_CASE(ELF, SHT_GNU_HASH);
STRINGIFY_ENUM_CASE(ELF, SHT_GNU_verdef);
ECase(SHT_LLVM_PART_PHDR);
ECase(SHT_LLVM_BB_ADDR_MAP_V0);
ECase(SHT_LLVM_BB_ADDR_MAP);
+ ECase(SHT_LLVM_OFFLOADING);
ECase(SHT_GNU_ATTRIBUTES);
ECase(SHT_GNU_HASH);
ECase(SHT_GNU_verdef);
@llvm.embedded.object = private constant [1 x i8] c"\00", section ".llvm.offloading"
@llvm.compiler.used = appending global [1 x ptr] [ptr @llvm.embedded.object], section "llvm.metadata"
-; CHECK-ELF: .section .llvm.offloading,"e"
+; CHECK-ELF: .section .llvm.offloading,"e",@llvm_offloading
; CHECK-COFF: .section .llvm.offloading,"dr"
.byte 1
.section .section6,"",@llvm_dependent_libraries
.byte 1
+.section .section7,"",@llvm_offloading
+.byte 1
# CHECK: Name: .section1
# CHECK-NEXT: Type: SHT_LLVM_BB_ADDR_MAP
# CHECK-NEXT: Type: SHT_LLVM_SYMPART
# CHECK: Name: .section6
# CHECK-NEXT: Type: SHT_LLVM_DEPENDENT_LIBRARIES
+# CHECK: Name: .section7
+# CHECK-NEXT: Type: SHT_LLVM_OFFLOADING
--- /dev/null
+# RUN: yaml2obj %s -o %t
+# RUN: llvm-readobj --sections %t | FileCheck -check-prefix=OBJ %s
+# RUN: obj2yaml %t | FileCheck -check-prefix=YAML %s
+
+--- !ELF
+FileHeader:
+ Class: ELFCLASS32
+ Data: ELFDATA2LSB
+ Type: ET_REL
+Sections:
+ - Name: .llvm.offloading
+ Type: SHT_LLVM_OFFLOADING
+ Flags: [ SHF_EXCLUDE ]
+
+# OBJ: Sections [
+# OBJ: Section {
+# OBJ: Index: 1
+# OBJ-NEXT: Name: .llvm.offloading (1)
+# OBJ-NEXT: Type: SHT_LLVM_OFFLOADING (0x6FFF4C0B)
+# OBJ-NEXT: Flags [ (0x80000000)
+# OBJ-NEXT: SHF_EXCLUDE (0x80000000)
+# OBJ-NEXT: ]
+
+
+# YAML: Sections:
+# YAML-NEXT: - Name: .llvm.offloading
+# YAML-NEXT: Type: SHT_LLVM_OFFLOADING
+# YAML-NEXT: Flags: [ SHF_EXCLUDE ]