[clang] [llvm] [MC,clang,llvm-readobj,yaml2obj] Support CREL relocation format (PR #91280)
via cfe-commits
cfe-commits at lists.llvm.org
Mon May 6 15:38:28 PDT 2024
llvmbot wrote:
<!--LLVM PR SUMMARY COMMENT-->
@llvm/pr-subscribers-clang-driver
@llvm/pr-subscribers-clang
Author: Fangrui Song (MaskRay)
<details>
<summary>Changes</summary>
CREL is a compact relocation format for the ELF object file format.
This patch adds integrated assembler support (using the RELA form),
which can be enabled with `clang -c -Wa,--crel,--experimental-crel`.
`-Wa,--experimental-crel` indicates that CREL is experimental and not
a standard. `-Wa,--experimental-crel` might be removed in the future.
* We take a section type code 20 from the generic range for `SHT_CREL`.
We avoided using `SHT_LLVM_` or `SHT_GNU_` to maintain broader
applicability for interested psABIs.
* In the extremely unlikely case the generic ABI assigns 20 to another
purpose, and existing toolchains generate relocatable files using that
code (unlikely if we ensure GNU and LLVM don't do this), any conflicts
would be the user's responsibility to resolve.
This patch also adds llvm-readobj support (for both REL and RELA forms)
to facilitate testing the assembler. Additionally, yaml2obj gains
support for the RELA form to aid testing with llvm-readobj.
Currently, linking the generated relocatable file with GNU ld will fail
because GNU ld doesn't support CREL yet.
unknown architecture of input file `a.o' is incompatible with i386:x86-64 output
lld will also produce an error when attempting to link a CREL relocatable file.
The support will come in a future change.
Link: https://discourse.llvm.org/t/rfc-crel-a-compact-relocation-format-for-elf/77600
---
Patch is 72.41 KiB, truncated to 20.00 KiB below, full version: https://github.com/llvm/llvm-project/pull/91280.diff
32 Files Affected:
- (modified) clang/include/clang/Basic/CodeGenOptions.def (+1)
- (modified) clang/include/clang/Basic/DiagnosticDriverKinds.td (+3)
- (modified) clang/include/clang/Driver/Options.td (+3)
- (modified) clang/lib/CodeGen/BackendUtil.cpp (+1)
- (modified) clang/lib/Driver/ToolChains/Clang.cpp (+18)
- (modified) clang/lib/Driver/ToolChains/CommonArgs.cpp (+21)
- (added) clang/test/Driver/crel.c (+24)
- (added) clang/test/Misc/cc1as-crel.s (+6)
- (modified) clang/tools/driver/cc1as_main.cpp (+6)
- (modified) llvm/include/llvm/BinaryFormat/DynamicTags.def (+2)
- (modified) llvm/include/llvm/BinaryFormat/ELF.h (+1)
- (modified) llvm/include/llvm/MC/MCTargetOptions.h (+3)
- (modified) llvm/include/llvm/MC/MCTargetOptionsCommandFlags.h (+1)
- (modified) llvm/include/llvm/Object/ELF.h (+5)
- (modified) llvm/include/llvm/Object/ELFObjectFile.h (+64-6)
- (modified) llvm/include/llvm/Object/ELFTypes.h (+25)
- (modified) llvm/lib/MC/ELFObjectWriter.cpp (+84-26)
- (modified) llvm/lib/MC/MCTargetOptionsCommandFlags.cpp (+6)
- (modified) llvm/lib/Object/ELF.cpp (+63)
- (modified) llvm/lib/ObjectYAML/ELFEmitter.cpp (+53-7)
- (modified) llvm/lib/ObjectYAML/ELFYAML.cpp (+2)
- (added) llvm/test/MC/ELF/crel-32.s (+16)
- (added) llvm/test/MC/ELF/crel.s (+100)
- (added) llvm/test/tools/llvm-readobj/ELF/crel.test (+180)
- (modified) llvm/test/tools/llvm-readobj/ELF/dynamic-reloc.test (+25-6)
- (modified) llvm/test/tools/llvm-readobj/ELF/relocation-errors.test (+18-1)
- (modified) llvm/test/tools/yaml2obj/ELF/dynamic-relocations.yaml (+4-1)
- (modified) llvm/test/tools/yaml2obj/ELF/reloc-sec-entry-size.yaml (+5)
- (added) llvm/test/tools/yaml2obj/ELF/relocation-crel.yaml (+63)
- (modified) llvm/test/tools/yaml2obj/ELF/relocation-missing-symbol.yaml (+2-1)
- (modified) llvm/test/tools/yaml2obj/ELF/relocation-type.yaml (+3-1)
- (modified) llvm/tools/llvm-readobj/ELFDumper.cpp (+75-6)
``````````diff
diff --git a/clang/include/clang/Basic/CodeGenOptions.def b/clang/include/clang/Basic/CodeGenOptions.def
index 340b08dd7e2a33..3229f77eef1fcc 100644
--- a/clang/include/clang/Basic/CodeGenOptions.def
+++ b/clang/include/clang/Basic/CodeGenOptions.def
@@ -36,6 +36,7 @@ VALUE_CODEGENOPT(Name, Bits, Default)
#endif
CODEGENOPT(DisableIntegratedAS, 1, 0) ///< -no-integrated-as
+CODEGENOPT(Crel, 1, 0) ///< -Wa,--crel
CODEGENOPT(RelaxELFRelocations, 1, 1) ///< -Wa,-mrelax-relocations={yes,no}
CODEGENOPT(AsmVerbose , 1, 0) ///< -dA, -fverbose-asm.
CODEGENOPT(PreserveAsmComments, 1, 1) ///< -dA, -fno-preserve-as-comments.
diff --git a/clang/include/clang/Basic/DiagnosticDriverKinds.td b/clang/include/clang/Basic/DiagnosticDriverKinds.td
index 9781fcaa4ff5e9..e9cea8967c1334 100644
--- a/clang/include/clang/Basic/DiagnosticDriverKinds.td
+++ b/clang/include/clang/Basic/DiagnosticDriverKinds.td
@@ -809,6 +809,9 @@ def warn_drv_missing_multilib : Warning<
def note_drv_available_multilibs : Note<
"available multilibs are:%0">;
+def err_drv_experimental_crel : Error<
+ "-Wa,--experimental-crel must be specified to use -Wa,--crel. CREL is experimental and takes a non-standard section type code">;
+
def warn_android_unversioned_fallback : Warning<
"Using unversioned Android target directory %0 for target %1. Unversioned"
" directories will not be used in Clang 19. Provide a versioned directory"
diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td
index c9f7c4e5f718b4..55f0c9aff6a49f 100644
--- a/clang/include/clang/Driver/Options.td
+++ b/clang/include/clang/Driver/Options.td
@@ -6958,6 +6958,9 @@ def massembler_no_warn : Flag<["-"], "massembler-no-warn">,
def massembler_fatal_warnings : Flag<["-"], "massembler-fatal-warnings">,
HelpText<"Make assembler warnings fatal">,
MarshallingInfoFlag<CodeGenOpts<"FatalWarnings">>;
+def crel : Flag<["--"], "crel">,
+ HelpText<"Enable CREL relocation format (ELF only)">,
+ MarshallingInfoFlag<CodeGenOpts<"Crel">>;
def mrelax_relocations_no : Flag<["-"], "mrelax-relocations=no">,
HelpText<"Disable x86 relax relocations">,
MarshallingInfoNegativeFlag<CodeGenOpts<"RelaxELFRelocations">>;
diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index 22c3f8642ad8eb..ed37085d69ac53 100644
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -474,6 +474,7 @@ static bool initTargetOptions(DiagnosticsEngine &Diags,
Options.MCOptions.AsmVerbose = CodeGenOpts.AsmVerbose;
Options.MCOptions.Dwarf64 = CodeGenOpts.Dwarf64;
Options.MCOptions.PreserveAsmComments = CodeGenOpts.PreserveAsmComments;
+ Options.MCOptions.Crel = CodeGenOpts.Crel;
Options.MCOptions.X86RelaxRelocations = CodeGenOpts.RelaxELFRelocations;
Options.MCOptions.CompressDebugSections =
CodeGenOpts.getCompressDebugSections();
diff --git a/clang/lib/Driver/ToolChains/Clang.cpp b/clang/lib/Driver/ToolChains/Clang.cpp
index 0a2ea96de73824..0f4d8aa3ad7938 100644
--- a/clang/lib/Driver/ToolChains/Clang.cpp
+++ b/clang/lib/Driver/ToolChains/Clang.cpp
@@ -2467,6 +2467,8 @@ static void CollectArgsForIntegratedAssembler(Compilation &C,
// arg after parsing the '-I' arg.
bool TakeNextArg = false;
+ const llvm::Triple &Triple = C.getDefaultToolChain().getTriple();
+ bool Crel = false, ExperimentalCrel = false;
bool UseRelaxRelocations = C.getDefaultToolChain().useRelaxRelocations();
bool UseNoExecStack = false;
const char *MipsTargetFeature = nullptr;
@@ -2590,6 +2592,12 @@ static void CollectArgsForIntegratedAssembler(Compilation &C,
Value == "-nocompress-debug-sections" ||
Value == "--nocompress-debug-sections") {
CmdArgs.push_back(Value.data());
+ } else if (Value == "--crel") {
+ Crel = true;
+ } else if (Value == "--no-crel") {
+ Crel = false;
+ } else if (Value == "--experimental-crel") {
+ ExperimentalCrel = true;
} else if (Value == "-mrelax-relocations=yes" ||
Value == "--mrelax-relocations=yes") {
UseRelaxRelocations = true;
@@ -2655,6 +2663,16 @@ static void CollectArgsForIntegratedAssembler(Compilation &C,
}
if (ImplicitIt.size())
AddARMImplicitITArgs(Args, CmdArgs, ImplicitIt);
+ if (Crel) {
+ if (!ExperimentalCrel)
+ D.Diag(diag::err_drv_experimental_crel);
+ if (Triple.isOSBinFormatELF() && !Triple.isMIPS()) {
+ CmdArgs.push_back("--crel");
+ } else {
+ D.Diag(diag::err_drv_unsupported_opt_for_target)
+ << "-Wa,--crel" << D.getTargetTriple();
+ }
+ }
if (!UseRelaxRelocations)
CmdArgs.push_back("-mrelax-relocations=no");
if (UseNoExecStack)
diff --git a/clang/lib/Driver/ToolChains/CommonArgs.cpp b/clang/lib/Driver/ToolChains/CommonArgs.cpp
index 6796b43a155020..8ba45aeafd0569 100644
--- a/clang/lib/Driver/ToolChains/CommonArgs.cpp
+++ b/clang/lib/Driver/ToolChains/CommonArgs.cpp
@@ -1072,6 +1072,27 @@ void tools::addLTOOptions(const ToolChain &ToolChain, const ArgList &Args,
addMachineOutlinerArgs(D, Args, CmdArgs, ToolChain.getEffectiveTriple(),
/*IsLTO=*/true, PluginOptPrefix);
+
+ for (const Arg *A : Args.filtered(options::OPT_Wa_COMMA)) {
+ bool Crel = false;
+ for (StringRef V : A->getValues()) {
+ if (V == "--crel")
+ Crel = true;
+ else if (V == "--no-crel")
+ Crel = false;
+ else
+ continue;
+ A->claim();
+ }
+ if (Crel) {
+ if (Triple.isOSBinFormatELF() && !Triple.isMIPS()) {
+ CmdArgs.push_back(Args.MakeArgString(Twine(PluginOptPrefix) + "-crel"));
+ } else {
+ D.Diag(diag::err_drv_unsupported_opt_for_target)
+ << "-Wa,--crel" << D.getTargetTriple();
+ }
+ }
+ }
}
/// Adds the '-lcgpu' and '-lmgpu' libraries to the compilation to include the
diff --git a/clang/test/Driver/crel.c b/clang/test/Driver/crel.c
new file mode 100644
index 00000000000000..0dc0507705d72d
--- /dev/null
+++ b/clang/test/Driver/crel.c
@@ -0,0 +1,24 @@
+// RUN: not %clang -### -c --target=x86_64 -Wa,--crel %s 2>&1 | FileCheck %s --check-prefix=NOEXP
+
+// NOEXP: error: -Wa,--experimental-crel must be specified to use -Wa,--crel. CREL is experimental and takes a non-standard section type code
+
+// RUN: %clang -### -c --target=x86_64 -Wa,--crel,--experimental-crel %s 2>&1 | FileCheck %s
+// RUN: %clang -### -c --target=x86_64 -Wa,--crel,--no-crel,--experimental-crel %s 2>&1 | FileCheck %s --check-prefix=NO
+// RUN: not %clang -### -c --target=arm64-apple-darwin -Wa,--crel,--experimental-crel %s 2>&1 | FileCheck %s --check-prefix=ERR
+// RUN: not %clang -### -c --target=mips64 -Wa,--crel,--experimental-crel %s 2>&1 | FileCheck %s --check-prefix=ERR
+
+// RUN: %clang -### -c --target=aarch64 -Werror -Wa,--crel,--experimental-crel -x assembler %s -Werror 2>&1 | FileCheck %s --check-prefix=ASM
+// RUN: not %clang -### -c --target=mips64 -Wa,--crel,--experimental-crel -x assembler %s 2>&1 | FileCheck %s --check-prefix=ERR
+
+// CHECK: "-cc1" {{.*}}"--crel"
+// NO: "-cc1"
+// NO-NOT: "--crel"
+// ASM: "-cc1as" {{.*}}"--crel"
+// ERR: error: unsupported option '-Wa,--crel' for target '{{.*}}'
+
+/// Don't bother with --experimental-crel for LTO.
+// RUN: %clang -### --target=x86_64-linux -Werror -flto -Wa,--crel %s 2>&1 | FileCheck %s --check-prefix=LTO
+// LTO: "-plugin-opt=-crel"
+
+// RUN: touch %t.o
+// RUN: not %clang -### --target=mips64-linux-gnu -flto -Wa,--crel %t.o 2>&1 | FileCheck %s --check-prefix=ERR
diff --git a/clang/test/Misc/cc1as-crel.s b/clang/test/Misc/cc1as-crel.s
new file mode 100644
index 00000000000000..953f2a1f3d3bcb
--- /dev/null
+++ b/clang/test/Misc/cc1as-crel.s
@@ -0,0 +1,6 @@
+// REQUIRES: x86-registered-target
+// RUN: %clang -cc1as -triple x86_64 %s -filetype obj --crel -o %t
+// RUN: llvm-readelf -S %t | FileCheck %s
+
+// CHECK: .crel.text CREL
+call foo
diff --git a/clang/tools/driver/cc1as_main.cpp b/clang/tools/driver/cc1as_main.cpp
index 86afe22fac24cc..9d53cca7a0bf5b 100644
--- a/clang/tools/driver/cc1as_main.cpp
+++ b/clang/tools/driver/cc1as_main.cpp
@@ -164,6 +164,9 @@ struct AssemblerInvocation {
LLVM_PREFERRED_TYPE(bool)
unsigned EmitCompactUnwindNonCanonical : 1;
+ LLVM_PREFERRED_TYPE(bool)
+ unsigned Crel : 1;
+
/// The name of the relocation model to use.
std::string RelocationModel;
@@ -204,6 +207,7 @@ struct AssemblerInvocation {
EmbedBitcode = 0;
EmitDwarfUnwind = EmitDwarfUnwindType::Default;
EmitCompactUnwindNonCanonical = false;
+ Crel = false;
}
static bool CreateFromArgs(AssemblerInvocation &Res,
@@ -373,6 +377,7 @@ bool AssemblerInvocation::CreateFromArgs(AssemblerInvocation &Opts,
Opts.EmitCompactUnwindNonCanonical =
Args.hasArg(OPT_femit_compact_unwind_non_canonical);
+ Opts.Crel = Args.hasArg(OPT_crel);
Opts.AsSecureLogFile = Args.getLastArgValue(OPT_as_secure_log_file);
@@ -429,6 +434,7 @@ static bool ExecuteAssemblerImpl(AssemblerInvocation &Opts,
MCOptions.MCRelaxAll = Opts.RelaxAll;
MCOptions.EmitDwarfUnwind = Opts.EmitDwarfUnwind;
MCOptions.EmitCompactUnwindNonCanonical = Opts.EmitCompactUnwindNonCanonical;
+ MCOptions.Crel = Opts.Crel;
MCOptions.X86RelaxRelocations = Opts.RelaxELFRelocations;
MCOptions.CompressDebugSections = Opts.CompressDebugSections;
MCOptions.AsSecureLogFile = Opts.AsSecureLogFile;
diff --git a/llvm/include/llvm/BinaryFormat/DynamicTags.def b/llvm/include/llvm/BinaryFormat/DynamicTags.def
index 1502d375f5c45d..d67a1e6de3678f 100644
--- a/llvm/include/llvm/BinaryFormat/DynamicTags.def
+++ b/llvm/include/llvm/BinaryFormat/DynamicTags.def
@@ -86,6 +86,8 @@ DYNAMIC_TAG(RELRSZ, 35) // Size of Relr relocation table.
DYNAMIC_TAG(RELR, 36) // Address of relocation table (Relr entries).
DYNAMIC_TAG(RELRENT, 37) // Size of a Relr relocation entry.
+DYNAMIC_TAG(CREL, 38) // CREL relocation table
+
DYNAMIC_TAG_MARKER(LOOS, 0x60000000) // Start of environment specific tags.
DYNAMIC_TAG_MARKER(HIOS, 0x6FFFFFFF) // End of environment specific tags.
DYNAMIC_TAG_MARKER(LOPROC, 0x70000000) // Start of processor specific tags.
diff --git a/llvm/include/llvm/BinaryFormat/ELF.h b/llvm/include/llvm/BinaryFormat/ELF.h
index f296acc2ca4bb9..b5c546d8b67e73 100644
--- a/llvm/include/llvm/BinaryFormat/ELF.h
+++ b/llvm/include/llvm/BinaryFormat/ELF.h
@@ -1079,6 +1079,7 @@ enum : unsigned {
// Experimental support for SHT_RELR sections. For details, see proposal
// at https://groups.google.com/forum/#!topic/generic-abi/bX460iggiKg
SHT_RELR = 19, // Relocation entries; only offsets.
+ SHT_CREL = 20, // CREL relocation entries
SHT_LOOS = 0x60000000, // Lowest operating system-specific type.
// Android packed relocation section types.
// https://android.googlesource.com/platform/bionic/+/6f12bfece5dcc01325e0abba56a46b1bcf991c69/tools/relocation_packer/src/elf_file.cc#37
diff --git a/llvm/include/llvm/MC/MCTargetOptions.h b/llvm/include/llvm/MC/MCTargetOptions.h
index 0cf2806bd48040..98317712250bf9 100644
--- a/llvm/include/llvm/MC/MCTargetOptions.h
+++ b/llvm/include/llvm/MC/MCTargetOptions.h
@@ -61,6 +61,9 @@ class MCTargetOptions {
bool Dwarf64 : 1;
+ // Use CREL relocation format for ELF.
+ bool Crel = false;
+
// If true, prefer R_X86_64_[REX_]GOTPCRELX to R_X86_64_GOTPCREL on x86-64
// ELF.
bool X86RelaxRelocations = true;
diff --git a/llvm/include/llvm/MC/MCTargetOptionsCommandFlags.h b/llvm/include/llvm/MC/MCTargetOptionsCommandFlags.h
index fc35eea09c4b3e..837f148e8f4ab4 100644
--- a/llvm/include/llvm/MC/MCTargetOptionsCommandFlags.h
+++ b/llvm/include/llvm/MC/MCTargetOptionsCommandFlags.h
@@ -49,6 +49,7 @@ bool getNoDeprecatedWarn();
bool getNoTypeCheck();
+bool getCrel();
bool getX86RelaxRelocations();
std::string getABIName();
diff --git a/llvm/include/llvm/Object/ELF.h b/llvm/include/llvm/Object/ELF.h
index 78b6b40cbddf67..26e38075f8db00 100644
--- a/llvm/include/llvm/Object/ELF.h
+++ b/llvm/include/llvm/Object/ELF.h
@@ -321,6 +321,11 @@ class ELFFile {
std::vector<Elf_Rel> decode_relrs(Elf_Relr_Range relrs) const;
+ uint64_t crelHeader(ArrayRef<uint8_t> Content) const;
+ using RelsOrRelas = std::pair<std::vector<Elf_Rel>, std::vector<Elf_Rela>>;
+ Expected<RelsOrRelas> decodeCrel(ArrayRef<uint8_t> Content) const;
+ Expected<RelsOrRelas> crels(const Elf_Shdr &Sec) const;
+
Expected<std::vector<Elf_Rela>> android_relas(const Elf_Shdr &Sec) const;
/// Iterate over program header table.
diff --git a/llvm/include/llvm/Object/ELFObjectFile.h b/llvm/include/llvm/Object/ELFObjectFile.h
index 8cc09e7fd7d551..505ea9ede313af 100644
--- a/llvm/include/llvm/Object/ELFObjectFile.h
+++ b/llvm/include/llvm/Object/ELFObjectFile.h
@@ -29,6 +29,7 @@
#include "llvm/Support/ELFAttributes.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/LEB128.h"
#include "llvm/Support/MemoryBufferRef.h"
#include "llvm/Support/ScopedPrinter.h"
#include "llvm/TargetParser/SubtargetFeature.h"
@@ -292,6 +293,9 @@ template <class ELFT> class ELFObjectFile : public ELFObjectFileBase {
const Elf_Shdr *DotSymtabSec = nullptr; // Symbol table section.
const Elf_Shdr *DotSymtabShndxSec = nullptr; // SHT_SYMTAB_SHNDX section.
+ // Hold CREL relocations for SectionRef::relocations().
+ mutable SmallVector<SmallVector<Elf_Crel, 0>, 0> Crels;
+
Error initContent() override;
void moveSymbolNext(DataRefImpl &Symb) const override;
@@ -446,6 +450,7 @@ template <class ELFT> class ELFObjectFile : public ELFObjectFileBase {
const Elf_Rel *getRel(DataRefImpl Rel) const;
const Elf_Rela *getRela(DataRefImpl Rela) const;
+ Elf_Crel getCrel(DataRefImpl Rel) const;
Expected<const Elf_Sym *> getSymbol(DataRefImpl Sym) const {
return EF.template getEntry<Elf_Sym>(Sym.d.a, Sym.d.b);
@@ -1022,6 +1027,40 @@ ELFObjectFile<ELFT>::section_rel_begin(DataRefImpl Sec) const {
uintptr_t SHT = reinterpret_cast<uintptr_t>((*SectionsOrErr).begin());
RelData.d.a = (Sec.p - SHT) / EF.getHeader().e_shentsize;
RelData.d.b = 0;
+ if (reinterpret_cast<const Elf_Shdr *>(Sec.p)->sh_type == ELF::SHT_CREL) {
+ if (RelData.d.a + 1 > Crels.size())
+ Crels.resize(RelData.d.a + 1);
+ if (Crels[RelData.d.a].empty()) {
+ ArrayRef<uint8_t> Content = cantFail(getSectionContents(Sec));
+ DataExtractor Data(Content, true, 8); // endian/class is irrelevant
+ DataExtractor::Cursor Cur(0);
+
+ const auto Hdr = Data.getULEB128(Cur);
+ const size_t Count = Hdr / 8, FlagBits = Hdr & 4 ? 3 : 2, Shift = Hdr % 4;
+ uintX_t Offset = 0, Addend = 0;
+ uint32_t Symidx = 0, Type = 0;
+ for (size_t i = 0; i != Count; ++i) {
+ const uint8_t B = Data.getU8(Cur);
+ Offset += B >> FlagBits;
+ if (B >= 0x80)
+ Offset +=
+ (Data.getULEB128(Cur) << (7 - FlagBits)) - (0x80 >> FlagBits);
+ if (B & 1)
+ Symidx += Data.getSLEB128(Cur);
+ if (B & 2)
+ Type += Data.getSLEB128(Cur);
+ if (B & 4)
+ Addend += Data.getSLEB128(Cur);
+ if (!Cur)
+ break;
+ Crels[RelData.d.a].push_back(
+ Elf_Crel{Offset << Shift, uint32_t(Symidx), Type,
+ std::make_signed_t<typename ELFT::uint>(Addend)});
+ }
+ if (!Cur)
+ consumeError(Cur.takeError());
+ }
+ }
return relocation_iterator(RelocationRef(RelData, this));
}
@@ -1030,9 +1069,13 @@ relocation_iterator
ELFObjectFile<ELFT>::section_rel_end(DataRefImpl Sec) const {
const Elf_Shdr *S = reinterpret_cast<const Elf_Shdr *>(Sec.p);
relocation_iterator Begin = section_rel_begin(Sec);
+ DataRefImpl RelData = Begin->getRawDataRefImpl();
+ if (S->sh_type == ELF::SHT_CREL) {
+ RelData.d.b = Crels[RelData.d.a].size();
+ return relocation_iterator(RelocationRef(RelData, this));
+ }
if (S->sh_type != ELF::SHT_RELA && S->sh_type != ELF::SHT_REL)
return Begin;
- DataRefImpl RelData = Begin->getRawDataRefImpl();
const Elf_Shdr *RelSec = getRelSection(RelData);
// Error check sh_link here so that getRelocationSymbol can just use it.
@@ -1050,7 +1093,7 @@ Expected<section_iterator>
ELFObjectFile<ELFT>::getRelocatedSection(DataRefImpl Sec) const {
const Elf_Shdr *EShdr = getSection(Sec);
uintX_t Type = EShdr->sh_type;
- if (Type != ELF::SHT_REL && Type != ELF::SHT_RELA)
+ if (Type != ELF::SHT_REL && Type != ELF::SHT_RELA && Type != ELF::SHT_CREL)
return section_end();
Expected<const Elf_Shdr *> SecOrErr = EF.getSection(EShdr->sh_info);
@@ -1070,7 +1113,9 @@ symbol_iterator
ELFObjectFile<ELFT>::getRelocationSymbol(DataRefImpl Rel) const {
uint32_t symbolIdx;
const Elf_Shdr *sec = getRelSection(Rel);
- if (sec->sh_type == ELF::SHT_REL)
+ if (sec->sh_type == ELF::SHT_CREL)
+ symbolIdx = getCrel(Rel).r_symidx;
+ else if (sec->sh_type == ELF::SHT_REL)
symbolIdx = getRel(Rel)->getSymbol(EF.isMips64EL());
else
symbolIdx = getRela(Rel)->getSymbol(EF.isMips64EL());
@@ -1087,6 +1132,8 @@ ELFObjectFile<ELFT>::getRelocationSymbol(DataRefImpl Rel) const {
template <class ELFT>
uint64_t ELFObjectFile<ELFT>::getRelocationOffset(DataRefImpl Rel) const {
const Elf_Shdr *sec = getRelSection(Rel);
+ if (sec->sh_type == ELF::SHT_CREL)
+ return getCrel(Rel).r_offset;
if (sec->sh_type == ELF::SHT_REL)
return getRel(Rel)->r_offset;
@@ -1096,6 +1143,8 @@ uint64_t ELFObjectFile<ELFT>::getRelocationOffset(DataRefImpl Rel) const {
template <class ELFT>
uint64_t ELFObjectFile<ELFT>::getRelocationType(DataRefImpl Rel) const {
const Elf_Shdr *sec = getRelSection(Rel);
+ if (sec->sh_type == ELF::SHT_CREL)
+ return getCrel(Rel).r_type;
if (sec->sh_type == ELF::SHT_REL)
return getRel(Rel)->getType(EF.isMips64EL());
else
@@ -1117,9 +1166,11 @@ void ELFObjectFile<ELFT>::getRelocationTypeName(
template <class ELFT>
Expected<int64_t>
ELFObjectFile<ELFT>::getRelocationAddend(DataRefImpl Rel) const {
- if (getRelSection(Rel)->sh_type != ELF::SHT_RELA)
- return createError("Section is not SHT_RELA");
- return (int64_t)getRela(Rel)->r_addend;
+ if (getRelSection(Rel)->sh_type == ELF::SHT_RELA)
+ return (int64_t)getRela(Rel)->r_addend;
+ if (getRelSection(Rel)->sh_type == ELF::SHT_CREL)
+ return (int64_t)getCrel(Rel).r_addend;
+ return createError("Section is not SHT_RELA");
}
template <class ELFT>
@@ -1142,6 +1193,13 @@ ELFObjectFile<ELFT>::getRela(DataRefImpl Rela) const {
return *Ret;
}
+template <class ELFT>
+typename ELFObjectFile<ELFT>::Elf_Crel
+ELFObjectFile<ELFT>::getCrel(DataRefImpl Rel) const {
+ assert(getRelSection(Rel)->sh_type == ELF::SHT_CREL);
+ return Crels[Rel.d.a][Rel.d.b];
+}
+
template <class ELFT>
Expected<ELFObjectFile<ELFT>>
ELFObjectFile<ELFT>::create(MemoryBufferRef Object, bool InitContent) {
diff --git a/llvm/include/llvm/Object/ELFTypes.h b/llvm/include/llvm/Object/ELFTypes.h
index 4ab23e4ea81b1a..aa07f4cacc4aba 100644
--- a/llvm/include/llvm/Object/ELFTypes.h
+++ b/llvm/include/llvm/Object/ELFTypes.h
@@ -32,6 +32,7 @@ template <class ELFT> struct Elf_Sym_Impl;
template <class ELFT> struct Elf_Dyn_Impl;
template <class ELFT> struct Elf_Phdr_Impl;
template <class ELFT, bool isRela> struct Elf_Rel_Impl;
+template <bool Is64> struct Elf_Crel_Impl;
template <class ELFT> struct Elf_Verdef_Impl;
template <class ELFT> struct Elf_Verdaux_Impl;
template <class ELFT> struct Elf_Verneed_Impl;
@@ -62,6 +63,7 @@ template <endianness E, bool Is64> struct ELFType {
using Phdr = Elf_Phdr_Impl<ELFType<E, Is64>>;
using Rel = Elf_Rel_Impl<ELFType<E, Is64>, false>;
using Rela = Elf_Rel_Impl<ELFType<E, Is64>, true>;
+ using Crel = Elf_Crel_Impl<Is64>;
using Relr = packed<uint>;
using Verdef = Elf_Verdef_Impl<ELFType<E, Is64>>;
using Verdaux = Elf_Verdaux_Impl<ELFType<E, Is64>>;
@@ -117,6 +119,7 @@ using ELF64BE = ELFType<llvm::endianness::big, true>;
using Elf_Phdr = typename ELFT::Phdr; \
using Elf_Rel = typename ELFT::Rel; \
using Elf_Rela = typename ELFT::Rela; \
+ using Elf_Crel = typename ELFT::Crel; \
using Elf_Relr = typename ELFT::Relr; ...
[truncated]
``````````
</details>
https://github.com/llvm/llvm-project/pull/91280
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