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merged 3 commits into from
Jul 21, 2025
Merged

[LLVM] Update CUDA ELF flags for their new ABI #149534

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15cb18c
[LLVM] Update CUDA ELF flags for their new ABI
jhuber6 Jul 18, 2025
a59408f
fixes
jhuber6 Jul 21, 2025
765d22d
fix
jhuber6 Jul 21, 2025
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21 changes: 19 additions & 2 deletions llvm/include/llvm/BinaryFormat/ELF.h
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Original file line number Diff line number Diff line change
Expand Up @@ -362,6 +362,7 @@ enum {
ELFOSABI_FENIXOS = 16, // FenixOS
ELFOSABI_CLOUDABI = 17, // Nuxi CloudABI
ELFOSABI_CUDA = 51, // NVIDIA CUDA architecture.
ELFOSABI_CUDA_V2 = 41, // NVIDIA CUDA architecture.
ELFOSABI_FIRST_ARCH = 64, // First architecture-specific OS ABI
ELFOSABI_AMDGPU_HSA = 64, // AMD HSA runtime
ELFOSABI_AMDGPU_PAL = 65, // AMD PAL runtime
Expand All @@ -385,6 +386,12 @@ enum {
ELFABIVERSION_AMDGPU_HSA_V6 = 4,
};

// CUDA OS ABI Version identification.
enum {
ELFABIVERSION_CUDA_V1 = 7,
ELFABIVERSION_CUDA_V2 = 8,
};

#define ELF_RELOC(name, value) name = value,

// X86_64 relocations.
Expand Down Expand Up @@ -921,7 +928,7 @@ enum {

// NVPTX specific e_flags.
enum : unsigned {
// Processor selection mask for EF_CUDA_SM* values.
// Processor selection mask for EF_CUDA_SM* values prior to blackwell.
EF_CUDA_SM = 0xff,

// SM based processor values.
Expand Down Expand Up @@ -954,12 +961,22 @@ enum : unsigned {
// The target is using 64-bit addressing.
EF_CUDA_64BIT_ADDRESS = 0x400,
// Set when using the sm_90a processor.
EF_CUDA_ACCELERATORS = 0x800,
EF_CUDA_ACCELERATORS_V1 = 0x800,
// Undocumented software feature.
EF_CUDA_SW_FLAG_V2 = 0x1000,

// Virtual processor selection mask for EF_CUDA_VIRTUAL_SM* values.
EF_CUDA_VIRTUAL_SM = 0xff0000,

// Processor selection mask for EF_CUDA_SM* values following blackwell.
EF_CUDA_SM_MASK = 0xff00,

// SM based processor values.
EF_CUDA_SM100 = 0x6400,
EF_CUDA_SM120 = 0x7800,

// Set when using an accelerator variant like sm_100a.
EF_CUDA_ACCELERATORS = 0x8,
};

// ELF Relocation types for BPF
Expand Down
1 change: 1 addition & 0 deletions llvm/include/llvm/Object/ELFObjectFile.h
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Original file line number Diff line number Diff line change
Expand Up @@ -1479,6 +1479,7 @@ template <class ELFT> Triple::OSType ELFObjectFile<ELFT>::getOS() const {
case ELF::ELFOSABI_OPENBSD:
return Triple::OpenBSD;
case ELF::ELFOSABI_CUDA:
case ELF::ELFOSABI_CUDA_V2:
return Triple::CUDA;
case ELF::ELFOSABI_AMDGPU_HSA:
return Triple::AMDHSA;
Expand Down
17 changes: 15 additions & 2 deletions llvm/lib/Object/ELFObjectFile.cpp
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Expand Up @@ -620,7 +620,9 @@ StringRef ELFObjectFileBase::getAMDGPUCPUName() const {

StringRef ELFObjectFileBase::getNVPTXCPUName() const {
assert(getEMachine() == ELF::EM_CUDA);
unsigned SM = getPlatformFlags() & ELF::EF_CUDA_SM;
unsigned SM = getEIdentABIVersion() == ELF::ELFABIVERSION_CUDA_V1
? getPlatformFlags() & ELF::EF_CUDA_SM
: getPlatformFlags() & ELF::EF_CUDA_SM_MASK;

switch (SM) {
// Fermi architecture.
Expand Down Expand Up @@ -679,7 +681,18 @@ StringRef ELFObjectFileBase::getNVPTXCPUName() const {

// Hopper architecture.
case ELF::EF_CUDA_SM90:
return getPlatformFlags() & ELF::EF_CUDA_ACCELERATORS ? "sm_90a" : "sm_90";
return getPlatformFlags() & ELF::EF_CUDA_ACCELERATORS_V1 ? "sm_90a"
: "sm_90";

// Blackwell architecture.
case ELF::EF_CUDA_SM100:
return getPlatformFlags() & ELF::EF_CUDA_ACCELERATORS ? "sm_100a"
: "sm_100";

// Rubin architecture.
case ELF::EF_CUDA_SM120:
return getPlatformFlags() & ELF::EF_CUDA_ACCELERATORS ? "sm_120a"
: "sm_120";
default:
llvm_unreachable("Unknown EF_CUDA_SM value");
}
Expand Down
70 changes: 38 additions & 32 deletions llvm/tools/llvm-readobj/ELFDumper.cpp
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Expand Up @@ -1083,26 +1083,25 @@ const EnumEntry<unsigned> ElfObjectFileType[] = {
};

const EnumEntry<unsigned> ElfOSABI[] = {
{"SystemV", "UNIX - System V", ELF::ELFOSABI_NONE},
{"HPUX", "UNIX - HP-UX", ELF::ELFOSABI_HPUX},
{"NetBSD", "UNIX - NetBSD", ELF::ELFOSABI_NETBSD},
{"GNU/Linux", "UNIX - GNU", ELF::ELFOSABI_LINUX},
{"GNU/Hurd", "GNU/Hurd", ELF::ELFOSABI_HURD},
{"Solaris", "UNIX - Solaris", ELF::ELFOSABI_SOLARIS},
{"AIX", "UNIX - AIX", ELF::ELFOSABI_AIX},
{"IRIX", "UNIX - IRIX", ELF::ELFOSABI_IRIX},
{"FreeBSD", "UNIX - FreeBSD", ELF::ELFOSABI_FREEBSD},
{"TRU64", "UNIX - TRU64", ELF::ELFOSABI_TRU64},
{"Modesto", "Novell - Modesto", ELF::ELFOSABI_MODESTO},
{"OpenBSD", "UNIX - OpenBSD", ELF::ELFOSABI_OPENBSD},
{"OpenVMS", "VMS - OpenVMS", ELF::ELFOSABI_OPENVMS},
{"NSK", "HP - Non-Stop Kernel", ELF::ELFOSABI_NSK},
{"AROS", "AROS", ELF::ELFOSABI_AROS},
{"FenixOS", "FenixOS", ELF::ELFOSABI_FENIXOS},
{"CloudABI", "CloudABI", ELF::ELFOSABI_CLOUDABI},
{"CUDA", "NVIDIA - CUDA", ELF::ELFOSABI_CUDA},
{"Standalone", "Standalone App", ELF::ELFOSABI_STANDALONE}
};
{"SystemV", "UNIX - System V", ELF::ELFOSABI_NONE},
{"HPUX", "UNIX - HP-UX", ELF::ELFOSABI_HPUX},
{"NetBSD", "UNIX - NetBSD", ELF::ELFOSABI_NETBSD},
{"GNU/Linux", "UNIX - GNU", ELF::ELFOSABI_LINUX},
{"GNU/Hurd", "GNU/Hurd", ELF::ELFOSABI_HURD},
{"Solaris", "UNIX - Solaris", ELF::ELFOSABI_SOLARIS},
{"AIX", "UNIX - AIX", ELF::ELFOSABI_AIX},
{"IRIX", "UNIX - IRIX", ELF::ELFOSABI_IRIX},
{"FreeBSD", "UNIX - FreeBSD", ELF::ELFOSABI_FREEBSD},
{"TRU64", "UNIX - TRU64", ELF::ELFOSABI_TRU64},
{"Modesto", "Novell - Modesto", ELF::ELFOSABI_MODESTO},
{"OpenBSD", "UNIX - OpenBSD", ELF::ELFOSABI_OPENBSD},
{"OpenVMS", "VMS - OpenVMS", ELF::ELFOSABI_OPENVMS},
{"NSK", "HP - Non-Stop Kernel", ELF::ELFOSABI_NSK},
{"AROS", "AROS", ELF::ELFOSABI_AROS},
{"FenixOS", "FenixOS", ELF::ELFOSABI_FENIXOS},
{"CloudABI", "CloudABI", ELF::ELFOSABI_CLOUDABI},
{"CUDA", "NVIDIA - CUDA", ELF::ELFOSABI_CUDA},
{"Standalone", "Standalone App", ELF::ELFOSABI_STANDALONE}};

const EnumEntry<unsigned> AMDGPUElfOSABI[] = {
{"AMDGPU_HSA", "AMDGPU - HSA", ELF::ELFOSABI_AMDGPU_HSA},
Expand Down Expand Up @@ -1667,16 +1666,17 @@ const EnumEntry<unsigned> ElfHeaderAMDGPUFlagsABIVersion4[] = {
};

const EnumEntry<unsigned> ElfHeaderNVPTXFlags[] = {
ENUM_ENT(EF_CUDA_SM20, "sm_20"), ENUM_ENT(EF_CUDA_SM21, "sm_21"),
ENUM_ENT(EF_CUDA_SM30, "sm_30"), ENUM_ENT(EF_CUDA_SM32, "sm_32"),
ENUM_ENT(EF_CUDA_SM35, "sm_35"), ENUM_ENT(EF_CUDA_SM37, "sm_37"),
ENUM_ENT(EF_CUDA_SM50, "sm_50"), ENUM_ENT(EF_CUDA_SM52, "sm_52"),
ENUM_ENT(EF_CUDA_SM53, "sm_53"), ENUM_ENT(EF_CUDA_SM60, "sm_60"),
ENUM_ENT(EF_CUDA_SM61, "sm_61"), ENUM_ENT(EF_CUDA_SM62, "sm_62"),
ENUM_ENT(EF_CUDA_SM70, "sm_70"), ENUM_ENT(EF_CUDA_SM72, "sm_72"),
ENUM_ENT(EF_CUDA_SM75, "sm_75"), ENUM_ENT(EF_CUDA_SM80, "sm_80"),
ENUM_ENT(EF_CUDA_SM86, "sm_86"), ENUM_ENT(EF_CUDA_SM87, "sm_87"),
ENUM_ENT(EF_CUDA_SM89, "sm_89"), ENUM_ENT(EF_CUDA_SM90, "sm_90"),
ENUM_ENT(EF_CUDA_SM20, "sm_20"), ENUM_ENT(EF_CUDA_SM21, "sm_21"),
ENUM_ENT(EF_CUDA_SM30, "sm_30"), ENUM_ENT(EF_CUDA_SM32, "sm_32"),
ENUM_ENT(EF_CUDA_SM35, "sm_35"), ENUM_ENT(EF_CUDA_SM37, "sm_37"),
ENUM_ENT(EF_CUDA_SM50, "sm_50"), ENUM_ENT(EF_CUDA_SM52, "sm_52"),
ENUM_ENT(EF_CUDA_SM53, "sm_53"), ENUM_ENT(EF_CUDA_SM60, "sm_60"),
ENUM_ENT(EF_CUDA_SM61, "sm_61"), ENUM_ENT(EF_CUDA_SM62, "sm_62"),
ENUM_ENT(EF_CUDA_SM70, "sm_70"), ENUM_ENT(EF_CUDA_SM72, "sm_72"),
ENUM_ENT(EF_CUDA_SM75, "sm_75"), ENUM_ENT(EF_CUDA_SM80, "sm_80"),
ENUM_ENT(EF_CUDA_SM86, "sm_86"), ENUM_ENT(EF_CUDA_SM87, "sm_87"),
ENUM_ENT(EF_CUDA_SM89, "sm_89"), ENUM_ENT(EF_CUDA_SM90, "sm_90"),
ENUM_ENT(EF_CUDA_SM100, "sm_100"), ENUM_ENT(EF_CUDA_SM120, "sm_120"),
};

const EnumEntry<unsigned> ElfHeaderRISCVFlags[] = {
Expand Down Expand Up @@ -3651,10 +3651,16 @@ template <class ELFT> void GNUELFDumper<ELFT>::printFileHeaders() {
else if (e.e_machine == EM_XTENSA)
ElfFlags = printFlags(e.e_flags, ArrayRef(ElfHeaderXtensaFlags),
unsigned(ELF::EF_XTENSA_MACH));
else if (e.e_machine == EM_CUDA)
else if (e.e_machine == EM_CUDA) {
ElfFlags = printFlags(e.e_flags, ArrayRef(ElfHeaderNVPTXFlags),
unsigned(ELF::EF_CUDA_SM));
else if (e.e_machine == EM_AMDGPU) {
if (e.e_ident[ELF::EI_ABIVERSION] == ELF::ELFABIVERSION_CUDA_V1 &&
(e.e_flags & ELF::EF_CUDA_ACCELERATORS_V1))
ElfFlags += "a";
else if (e.e_ident[ELF::EI_ABIVERSION] == ELF::ELFABIVERSION_CUDA_V2 &&
(e.e_flags & ELF::EF_CUDA_ACCELERATORS))
ElfFlags += "a";
} else if (e.e_machine == EM_AMDGPU) {
switch (e.e_ident[ELF::EI_ABIVERSION]) {
default:
break;
Expand Down
23 changes: 15 additions & 8 deletions offload/plugins-nextgen/common/src/Utils/ELF.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -60,23 +60,30 @@ static Expected<bool>
checkMachineImpl(const object::ELFObjectFile<ELFT> &ELFObj, uint16_t EMachine) {
const auto Header = ELFObj.getELFFile().getHeader();
if (Header.e_type != ET_EXEC && Header.e_type != ET_DYN)
return createError("Only executable ELF files are supported");
return createError("only executable ELF files are supported");

if (Header.e_machine == EM_AMDGPU) {
if (Header.e_ident[EI_OSABI] != ELFOSABI_AMDGPU_HSA)
return createError("Invalid AMD OS/ABI, must be AMDGPU_HSA");
return createError("invalid AMD OS/ABI, must be AMDGPU_HSA");
if (Header.e_ident[EI_ABIVERSION] != ELFABIVERSION_AMDGPU_HSA_V5 &&
Header.e_ident[EI_ABIVERSION] != ELFABIVERSION_AMDGPU_HSA_V6)
return createError("Invalid AMD ABI version, must be version 5 or above");
return createError("invalid AMD ABI version, must be version 5 or above");
if ((Header.e_flags & EF_AMDGPU_MACH) < EF_AMDGPU_MACH_AMDGCN_GFX700 ||
(Header.e_flags & EF_AMDGPU_MACH) >
EF_AMDGPU_MACH_AMDGCN_GFX9_4_GENERIC)
return createError("Unsupported AMDGPU architecture");
return createError("unsupported AMDGPU architecture");
} else if (Header.e_machine == EM_CUDA) {
if (~Header.e_flags & EF_CUDA_64BIT_ADDRESS)
return createError("Invalid CUDA addressing mode");
if ((Header.e_flags & EF_CUDA_SM) < EF_CUDA_SM35)
return createError("Unsupported NVPTX architecture");
if (Header.e_ident[EI_ABIVERSION] == ELFABIVERSION_CUDA_V1) {
if (~Header.e_flags & EF_CUDA_64BIT_ADDRESS)
return createError("invalid CUDA addressing mode");
if ((Header.e_flags & EF_CUDA_SM) < EF_CUDA_SM35)
return createError("unsupported NVPTX architecture");
} else if (Header.e_ident[EI_ABIVERSION] == ELFABIVERSION_CUDA_V2) {
if ((Header.e_flags & EF_CUDA_SM) < EF_CUDA_SM100)
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Just want to point this out again such that it does not get lost in the resolved thread.

Suggested change
if ((Header.e_flags & EF_CUDA_SM) < EF_CUDA_SM100)
if ((Header.e_flags & EF_CUDA_SM_MASK) < EF_CUDA_SM100)

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Thanks, missed that one.

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@jhuber6 Perfect, all good now from my side and testing with sm_120 (sorry for mixing up accounts now)

return createError("unsupported NVPTX architecture");
} else {
return createError("invalid CUDA ABI version");
}
}

return Header.e_machine == EMachine;
Expand Down
6 changes: 5 additions & 1 deletion offload/plugins-nextgen/cuda/src/rtl.cpp
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Expand Up @@ -1444,7 +1444,11 @@ struct CUDAPluginTy final : public GenericPluginTy {
return ElfOrErr.takeError();

// Get the numeric value for the image's `sm_` value.
auto SM = ElfOrErr->getPlatformFlags() & ELF::EF_CUDA_SM;
const auto Header = ElfOrErr->getELFFile().getHeader();
unsigned SM =
Header.e_ident[ELF::EI_ABIVERSION] == ELF::ELFABIVERSION_CUDA_V1
? Header.e_flags & ELF::EF_CUDA_SM
: (Header.e_flags & ELF::EF_CUDA_SM_MASK) >> 8;

CUdevice Device;
CUresult Res = cuDeviceGet(&Device, DeviceId);
Expand Down
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