summaryrefslogtreecommitdiffstats
path: root/third_party/rust/object/src/write/elf/object.rs
diff options
context:
space:
mode:
Diffstat (limited to 'third_party/rust/object/src/write/elf/object.rs')
-rw-r--r--third_party/rust/object/src/write/elf/object.rs838
1 files changed, 838 insertions, 0 deletions
diff --git a/third_party/rust/object/src/write/elf/object.rs b/third_party/rust/object/src/write/elf/object.rs
new file mode 100644
index 0000000000..305d522e66
--- /dev/null
+++ b/third_party/rust/object/src/write/elf/object.rs
@@ -0,0 +1,838 @@
+use alloc::vec::Vec;
+
+use crate::elf;
+use crate::write::elf::writer::*;
+use crate::write::string::StringId;
+use crate::write::*;
+use crate::AddressSize;
+
+#[derive(Clone, Copy)]
+struct ComdatOffsets {
+ offset: usize,
+ str_id: StringId,
+}
+
+#[derive(Clone, Copy)]
+struct SectionOffsets {
+ index: SectionIndex,
+ offset: usize,
+ str_id: StringId,
+ reloc_offset: usize,
+ reloc_str_id: Option<StringId>,
+}
+
+#[derive(Default, Clone, Copy)]
+struct SymbolOffsets {
+ index: SymbolIndex,
+ str_id: Option<StringId>,
+}
+
+impl<'a> Object<'a> {
+ pub(crate) fn elf_section_info(
+ &self,
+ section: StandardSection,
+ ) -> (&'static [u8], &'static [u8], SectionKind) {
+ match section {
+ StandardSection::Text => (&[], &b".text"[..], SectionKind::Text),
+ StandardSection::Data => (&[], &b".data"[..], SectionKind::Data),
+ StandardSection::ReadOnlyData | StandardSection::ReadOnlyString => {
+ (&[], &b".rodata"[..], SectionKind::ReadOnlyData)
+ }
+ StandardSection::ReadOnlyDataWithRel => {
+ (&[], b".data.rel.ro", SectionKind::ReadOnlyDataWithRel)
+ }
+ StandardSection::UninitializedData => {
+ (&[], &b".bss"[..], SectionKind::UninitializedData)
+ }
+ StandardSection::Tls => (&[], &b".tdata"[..], SectionKind::Tls),
+ StandardSection::UninitializedTls => {
+ (&[], &b".tbss"[..], SectionKind::UninitializedTls)
+ }
+ StandardSection::TlsVariables => {
+ // Unsupported section.
+ (&[], &[], SectionKind::TlsVariables)
+ }
+ StandardSection::Common => {
+ // Unsupported section.
+ (&[], &[], SectionKind::Common)
+ }
+ }
+ }
+
+ pub(crate) fn elf_subsection_name(&self, section: &[u8], value: &[u8]) -> Vec<u8> {
+ let mut name = section.to_vec();
+ name.push(b'.');
+ name.extend_from_slice(value);
+ name
+ }
+
+ fn elf_has_relocation_addend(&self) -> Result<bool> {
+ Ok(match self.architecture {
+ Architecture::Aarch64 => true,
+ Architecture::Aarch64_Ilp32 => true,
+ Architecture::Arm => false,
+ Architecture::Avr => true,
+ Architecture::Bpf => false,
+ Architecture::I386 => false,
+ Architecture::X86_64 => true,
+ Architecture::X86_64_X32 => true,
+ Architecture::Hexagon => true,
+ Architecture::LoongArch64 => true,
+ Architecture::Mips => false,
+ Architecture::Mips64 => true,
+ Architecture::Msp430 => true,
+ Architecture::PowerPc => true,
+ Architecture::PowerPc64 => true,
+ Architecture::Riscv64 => true,
+ Architecture::Riscv32 => true,
+ Architecture::S390x => true,
+ Architecture::Sbf => false,
+ Architecture::Sparc64 => true,
+ Architecture::Xtensa => true,
+ _ => {
+ return Err(Error(format!(
+ "unimplemented architecture {:?}",
+ self.architecture
+ )));
+ }
+ })
+ }
+
+ pub(crate) fn elf_fixup_relocation(&mut self, mut relocation: &mut Relocation) -> Result<i64> {
+ // Return true if we should use a section symbol to avoid preemption.
+ fn want_section_symbol(relocation: &Relocation, symbol: &Symbol) -> bool {
+ if symbol.scope != SymbolScope::Dynamic {
+ // Only dynamic symbols can be preemptible.
+ return false;
+ }
+ match symbol.kind {
+ SymbolKind::Text | SymbolKind::Data => {}
+ _ => return false,
+ }
+ match relocation.kind {
+ // Anything using GOT or PLT is preemptible.
+ // We also require that `Other` relocations must already be correct.
+ RelocationKind::Got
+ | RelocationKind::GotRelative
+ | RelocationKind::GotBaseRelative
+ | RelocationKind::PltRelative
+ | RelocationKind::Elf(_) => return false,
+ // Absolute relocations are preemptible for non-local data.
+ // TODO: not sure if this rule is exactly correct
+ // This rule was added to handle global data references in debuginfo.
+ // Maybe this should be a new relocation kind so that the caller can decide.
+ RelocationKind::Absolute => {
+ if symbol.kind == SymbolKind::Data {
+ return false;
+ }
+ }
+ _ => {}
+ }
+ true
+ }
+
+ // Use section symbols for relocations where required to avoid preemption.
+ // Otherwise, the linker will fail with:
+ // relocation R_X86_64_PC32 against symbol `SomeSymbolName' can not be used when
+ // making a shared object; recompile with -fPIC
+ let symbol = &self.symbols[relocation.symbol.0];
+ if want_section_symbol(relocation, symbol) {
+ if let Some(section) = symbol.section.id() {
+ relocation.addend += symbol.value as i64;
+ relocation.symbol = self.section_symbol(section);
+ }
+ }
+
+ // Determine whether the addend is stored in the relocation or the data.
+ if self.elf_has_relocation_addend()? {
+ Ok(0)
+ } else {
+ let constant = relocation.addend;
+ relocation.addend = 0;
+ Ok(constant)
+ }
+ }
+
+ pub(crate) fn elf_write(&self, buffer: &mut dyn WritableBuffer) -> Result<()> {
+ // Create reloc section header names so we can reference them.
+ let is_rela = self.elf_has_relocation_addend()?;
+ let reloc_names: Vec<_> = self
+ .sections
+ .iter()
+ .map(|section| {
+ let mut reloc_name = Vec::with_capacity(
+ if is_rela { ".rela".len() } else { ".rel".len() } + section.name.len(),
+ );
+ if !section.relocations.is_empty() {
+ reloc_name.extend_from_slice(if is_rela {
+ &b".rela"[..]
+ } else {
+ &b".rel"[..]
+ });
+ reloc_name.extend_from_slice(&section.name);
+ }
+ reloc_name
+ })
+ .collect();
+
+ // Start calculating offsets of everything.
+ let is_64 = match self.architecture.address_size().unwrap() {
+ AddressSize::U8 | AddressSize::U16 | AddressSize::U32 => false,
+ AddressSize::U64 => true,
+ };
+ let mut writer = Writer::new(self.endian, is_64, buffer);
+ writer.reserve_file_header();
+
+ // Calculate size of section data.
+ let mut comdat_offsets = Vec::with_capacity(self.comdats.len());
+ for comdat in &self.comdats {
+ if comdat.kind != ComdatKind::Any {
+ return Err(Error(format!(
+ "unsupported COMDAT symbol `{}` kind {:?}",
+ self.symbols[comdat.symbol.0].name().unwrap_or(""),
+ comdat.kind
+ )));
+ }
+
+ writer.reserve_section_index();
+ let offset = writer.reserve_comdat(comdat.sections.len());
+ let str_id = writer.add_section_name(b".group");
+ comdat_offsets.push(ComdatOffsets { offset, str_id });
+ }
+ let mut section_offsets = Vec::with_capacity(self.sections.len());
+ for (section, reloc_name) in self.sections.iter().zip(reloc_names.iter()) {
+ let index = writer.reserve_section_index();
+ let offset = writer.reserve(section.data.len(), section.align as usize);
+ let str_id = writer.add_section_name(&section.name);
+ let mut reloc_str_id = None;
+ if !section.relocations.is_empty() {
+ writer.reserve_section_index();
+ reloc_str_id = Some(writer.add_section_name(reloc_name));
+ }
+ section_offsets.push(SectionOffsets {
+ index,
+ offset,
+ str_id,
+ // Relocation data is reserved later.
+ reloc_offset: 0,
+ reloc_str_id,
+ });
+ }
+
+ // Calculate index of symbols and add symbol strings to strtab.
+ let mut symbol_offsets = vec![SymbolOffsets::default(); self.symbols.len()];
+ writer.reserve_null_symbol_index();
+ // Local symbols must come before global.
+ for (index, symbol) in self.symbols.iter().enumerate() {
+ if symbol.is_local() {
+ let section_index = symbol.section.id().map(|s| section_offsets[s.0].index);
+ symbol_offsets[index].index = writer.reserve_symbol_index(section_index);
+ }
+ }
+ let symtab_num_local = writer.symbol_count();
+ for (index, symbol) in self.symbols.iter().enumerate() {
+ if !symbol.is_local() {
+ let section_index = symbol.section.id().map(|s| section_offsets[s.0].index);
+ symbol_offsets[index].index = writer.reserve_symbol_index(section_index);
+ }
+ }
+ for (index, symbol) in self.symbols.iter().enumerate() {
+ if symbol.kind != SymbolKind::Section && !symbol.name.is_empty() {
+ symbol_offsets[index].str_id = Some(writer.add_string(&symbol.name));
+ }
+ }
+
+ // Calculate size of symbols.
+ writer.reserve_symtab_section_index();
+ writer.reserve_symtab();
+ if writer.symtab_shndx_needed() {
+ writer.reserve_symtab_shndx_section_index();
+ }
+ writer.reserve_symtab_shndx();
+ writer.reserve_strtab_section_index();
+ writer.reserve_strtab();
+
+ // Calculate size of relocations.
+ for (index, section) in self.sections.iter().enumerate() {
+ let count = section.relocations.len();
+ if count != 0 {
+ section_offsets[index].reloc_offset = writer.reserve_relocations(count, is_rela);
+ }
+ }
+
+ // Calculate size of section headers.
+ writer.reserve_shstrtab_section_index();
+ writer.reserve_shstrtab();
+ writer.reserve_section_headers();
+
+ // Start writing.
+ let e_type = elf::ET_REL;
+ let e_machine = match self.architecture {
+ Architecture::Aarch64 => elf::EM_AARCH64,
+ Architecture::Aarch64_Ilp32 => elf::EM_AARCH64,
+ Architecture::Arm => elf::EM_ARM,
+ Architecture::Avr => elf::EM_AVR,
+ Architecture::Bpf => elf::EM_BPF,
+ Architecture::I386 => elf::EM_386,
+ Architecture::X86_64 => elf::EM_X86_64,
+ Architecture::X86_64_X32 => elf::EM_X86_64,
+ Architecture::Hexagon => elf::EM_HEXAGON,
+ Architecture::LoongArch64 => elf::EM_LOONGARCH,
+ Architecture::Mips => elf::EM_MIPS,
+ Architecture::Mips64 => elf::EM_MIPS,
+ Architecture::Msp430 => elf::EM_MSP430,
+ Architecture::PowerPc => elf::EM_PPC,
+ Architecture::PowerPc64 => elf::EM_PPC64,
+ Architecture::Riscv32 => elf::EM_RISCV,
+ Architecture::Riscv64 => elf::EM_RISCV,
+ Architecture::S390x => elf::EM_S390,
+ Architecture::Sbf => elf::EM_SBF,
+ Architecture::Sparc64 => elf::EM_SPARCV9,
+ Architecture::Xtensa => elf::EM_XTENSA,
+ _ => {
+ return Err(Error(format!(
+ "unimplemented architecture {:?}",
+ self.architecture
+ )));
+ }
+ };
+ let (os_abi, abi_version, e_flags) = if let FileFlags::Elf {
+ os_abi,
+ abi_version,
+ e_flags,
+ } = self.flags
+ {
+ (os_abi, abi_version, e_flags)
+ } else {
+ (elf::ELFOSABI_NONE, 0, 0)
+ };
+ writer.write_file_header(&FileHeader {
+ os_abi,
+ abi_version,
+ e_type,
+ e_machine,
+ e_entry: 0,
+ e_flags,
+ })?;
+
+ // Write section data.
+ for comdat in &self.comdats {
+ writer.write_comdat_header();
+ for section in &comdat.sections {
+ writer.write_comdat_entry(section_offsets[section.0].index);
+ }
+ }
+ for (index, section) in self.sections.iter().enumerate() {
+ let len = section.data.len();
+ if len != 0 {
+ writer.write_align(section.align as usize);
+ debug_assert_eq!(section_offsets[index].offset, writer.len());
+ writer.write(&section.data);
+ }
+ }
+
+ // Write symbols.
+ writer.write_null_symbol();
+ let mut write_symbol = |index: usize, symbol: &Symbol| -> Result<()> {
+ let st_info = if let SymbolFlags::Elf { st_info, .. } = symbol.flags {
+ st_info
+ } else {
+ let st_type = match symbol.kind {
+ SymbolKind::Null => elf::STT_NOTYPE,
+ SymbolKind::Text => {
+ if symbol.is_undefined() {
+ elf::STT_NOTYPE
+ } else {
+ elf::STT_FUNC
+ }
+ }
+ SymbolKind::Data => {
+ if symbol.is_undefined() {
+ elf::STT_NOTYPE
+ } else if symbol.is_common() {
+ elf::STT_COMMON
+ } else {
+ elf::STT_OBJECT
+ }
+ }
+ SymbolKind::Section => elf::STT_SECTION,
+ SymbolKind::File => elf::STT_FILE,
+ SymbolKind::Tls => elf::STT_TLS,
+ SymbolKind::Label => elf::STT_NOTYPE,
+ SymbolKind::Unknown => {
+ if symbol.is_undefined() {
+ elf::STT_NOTYPE
+ } else {
+ return Err(Error(format!(
+ "unimplemented symbol `{}` kind {:?}",
+ symbol.name().unwrap_or(""),
+ symbol.kind
+ )));
+ }
+ }
+ };
+ let st_bind = if symbol.weak {
+ elf::STB_WEAK
+ } else if symbol.is_undefined() {
+ elf::STB_GLOBAL
+ } else if symbol.is_local() {
+ elf::STB_LOCAL
+ } else {
+ elf::STB_GLOBAL
+ };
+ (st_bind << 4) + st_type
+ };
+ let st_other = if let SymbolFlags::Elf { st_other, .. } = symbol.flags {
+ st_other
+ } else if symbol.scope == SymbolScope::Linkage {
+ elf::STV_HIDDEN
+ } else {
+ elf::STV_DEFAULT
+ };
+ let (st_shndx, section) = match symbol.section {
+ SymbolSection::None => {
+ debug_assert_eq!(symbol.kind, SymbolKind::File);
+ (elf::SHN_ABS, None)
+ }
+ SymbolSection::Undefined => (elf::SHN_UNDEF, None),
+ SymbolSection::Absolute => (elf::SHN_ABS, None),
+ SymbolSection::Common => (elf::SHN_COMMON, None),
+ SymbolSection::Section(id) => (0, Some(section_offsets[id.0].index)),
+ };
+ writer.write_symbol(&Sym {
+ name: symbol_offsets[index].str_id,
+ section,
+ st_info,
+ st_other,
+ st_shndx,
+ st_value: symbol.value,
+ st_size: symbol.size,
+ });
+ Ok(())
+ };
+ for (index, symbol) in self.symbols.iter().enumerate() {
+ if symbol.is_local() {
+ write_symbol(index, symbol)?;
+ }
+ }
+ for (index, symbol) in self.symbols.iter().enumerate() {
+ if !symbol.is_local() {
+ write_symbol(index, symbol)?;
+ }
+ }
+ writer.write_symtab_shndx();
+ writer.write_strtab();
+
+ // Write relocations.
+ for (index, section) in self.sections.iter().enumerate() {
+ if !section.relocations.is_empty() {
+ writer.write_align_relocation();
+ debug_assert_eq!(section_offsets[index].reloc_offset, writer.len());
+ for reloc in &section.relocations {
+ let r_type = match self.architecture {
+ Architecture::Aarch64 => match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, RelocationEncoding::Generic, 64) => {
+ elf::R_AARCH64_ABS64
+ }
+ (RelocationKind::Absolute, RelocationEncoding::Generic, 32) => {
+ elf::R_AARCH64_ABS32
+ }
+ (RelocationKind::Absolute, RelocationEncoding::Generic, 16) => {
+ elf::R_AARCH64_ABS16
+ }
+ (RelocationKind::Relative, RelocationEncoding::Generic, 64) => {
+ elf::R_AARCH64_PREL64
+ }
+ (RelocationKind::Relative, RelocationEncoding::Generic, 32) => {
+ elf::R_AARCH64_PREL32
+ }
+ (RelocationKind::Relative, RelocationEncoding::Generic, 16) => {
+ elf::R_AARCH64_PREL16
+ }
+ (RelocationKind::Relative, RelocationEncoding::AArch64Call, 26)
+ | (RelocationKind::PltRelative, RelocationEncoding::AArch64Call, 26) => {
+ elf::R_AARCH64_CALL26
+ }
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::Aarch64_Ilp32 => {
+ match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, RelocationEncoding::Generic, 32) => {
+ elf::R_AARCH64_P32_ABS32
+ }
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!(
+ "unimplemented relocation {:?}",
+ reloc
+ )));
+ }
+ }
+ }
+ Architecture::Arm => match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, _, 32) => elf::R_ARM_ABS32,
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::Avr => match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, _, 32) => elf::R_AVR_32,
+ (RelocationKind::Absolute, _, 16) => elf::R_AVR_16,
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::Bpf => match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, _, 64) => elf::R_BPF_64_64,
+ (RelocationKind::Absolute, _, 32) => elf::R_BPF_64_32,
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::I386 => match (reloc.kind, reloc.size) {
+ (RelocationKind::Absolute, 32) => elf::R_386_32,
+ (RelocationKind::Relative, 32) => elf::R_386_PC32,
+ (RelocationKind::Got, 32) => elf::R_386_GOT32,
+ (RelocationKind::PltRelative, 32) => elf::R_386_PLT32,
+ (RelocationKind::GotBaseOffset, 32) => elf::R_386_GOTOFF,
+ (RelocationKind::GotBaseRelative, 32) => elf::R_386_GOTPC,
+ (RelocationKind::Absolute, 16) => elf::R_386_16,
+ (RelocationKind::Relative, 16) => elf::R_386_PC16,
+ (RelocationKind::Absolute, 8) => elf::R_386_8,
+ (RelocationKind::Relative, 8) => elf::R_386_PC8,
+ (RelocationKind::Elf(x), _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::X86_64 | Architecture::X86_64_X32 => {
+ match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, RelocationEncoding::Generic, 64) => {
+ elf::R_X86_64_64
+ }
+ (RelocationKind::Relative, _, 32) => elf::R_X86_64_PC32,
+ (RelocationKind::Got, _, 32) => elf::R_X86_64_GOT32,
+ (RelocationKind::PltRelative, _, 32) => elf::R_X86_64_PLT32,
+ (RelocationKind::GotRelative, _, 32) => elf::R_X86_64_GOTPCREL,
+ (RelocationKind::Absolute, RelocationEncoding::Generic, 32) => {
+ elf::R_X86_64_32
+ }
+ (RelocationKind::Absolute, RelocationEncoding::X86Signed, 32) => {
+ elf::R_X86_64_32S
+ }
+ (RelocationKind::Absolute, _, 16) => elf::R_X86_64_16,
+ (RelocationKind::Relative, _, 16) => elf::R_X86_64_PC16,
+ (RelocationKind::Absolute, _, 8) => elf::R_X86_64_8,
+ (RelocationKind::Relative, _, 8) => elf::R_X86_64_PC8,
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!(
+ "unimplemented relocation {:?}",
+ reloc
+ )));
+ }
+ }
+ }
+ Architecture::Hexagon => match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, _, 32) => elf::R_HEX_32,
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::LoongArch64 => match (reloc.kind, reloc.encoding, reloc.size)
+ {
+ (RelocationKind::Absolute, _, 32) => elf::R_LARCH_32,
+ (RelocationKind::Absolute, _, 64) => elf::R_LARCH_64,
+ (RelocationKind::Relative, _, 32) => elf::R_LARCH_32_PCREL,
+ (RelocationKind::Relative, RelocationEncoding::LoongArchBranch, 16)
+ | (
+ RelocationKind::PltRelative,
+ RelocationEncoding::LoongArchBranch,
+ 16,
+ ) => elf::R_LARCH_B16,
+ (RelocationKind::Relative, RelocationEncoding::LoongArchBranch, 21)
+ | (
+ RelocationKind::PltRelative,
+ RelocationEncoding::LoongArchBranch,
+ 21,
+ ) => elf::R_LARCH_B21,
+ (RelocationKind::Relative, RelocationEncoding::LoongArchBranch, 26)
+ | (
+ RelocationKind::PltRelative,
+ RelocationEncoding::LoongArchBranch,
+ 26,
+ ) => elf::R_LARCH_B26,
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::Mips | Architecture::Mips64 => {
+ match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, _, 16) => elf::R_MIPS_16,
+ (RelocationKind::Absolute, _, 32) => elf::R_MIPS_32,
+ (RelocationKind::Absolute, _, 64) => elf::R_MIPS_64,
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!(
+ "unimplemented relocation {:?}",
+ reloc
+ )));
+ }
+ }
+ }
+ Architecture::Msp430 => match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, _, 32) => elf::R_MSP430_32,
+ (RelocationKind::Absolute, _, 16) => elf::R_MSP430_16_BYTE,
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::PowerPc => match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, _, 32) => elf::R_PPC_ADDR32,
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::PowerPc64 => match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, _, 32) => elf::R_PPC64_ADDR32,
+ (RelocationKind::Absolute, _, 64) => elf::R_PPC64_ADDR64,
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::Riscv32 | Architecture::Riscv64 => {
+ match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, _, 32) => elf::R_RISCV_32,
+ (RelocationKind::Absolute, _, 64) => elf::R_RISCV_64,
+ (RelocationKind::Relative, RelocationEncoding::Generic, 32) => {
+ elf::R_RISCV_32_PCREL
+ }
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!(
+ "unimplemented relocation {:?}",
+ reloc
+ )));
+ }
+ }
+ }
+ Architecture::S390x => match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, RelocationEncoding::Generic, 8) => {
+ elf::R_390_8
+ }
+ (RelocationKind::Absolute, RelocationEncoding::Generic, 16) => {
+ elf::R_390_16
+ }
+ (RelocationKind::Absolute, RelocationEncoding::Generic, 32) => {
+ elf::R_390_32
+ }
+ (RelocationKind::Absolute, RelocationEncoding::Generic, 64) => {
+ elf::R_390_64
+ }
+ (RelocationKind::Relative, RelocationEncoding::Generic, 16) => {
+ elf::R_390_PC16
+ }
+ (RelocationKind::Relative, RelocationEncoding::Generic, 32) => {
+ elf::R_390_PC32
+ }
+ (RelocationKind::Relative, RelocationEncoding::Generic, 64) => {
+ elf::R_390_PC64
+ }
+ (RelocationKind::Relative, RelocationEncoding::S390xDbl, 16) => {
+ elf::R_390_PC16DBL
+ }
+ (RelocationKind::Relative, RelocationEncoding::S390xDbl, 32) => {
+ elf::R_390_PC32DBL
+ }
+ (RelocationKind::PltRelative, RelocationEncoding::S390xDbl, 16) => {
+ elf::R_390_PLT16DBL
+ }
+ (RelocationKind::PltRelative, RelocationEncoding::S390xDbl, 32) => {
+ elf::R_390_PLT32DBL
+ }
+ (RelocationKind::Got, RelocationEncoding::Generic, 16) => {
+ elf::R_390_GOT16
+ }
+ (RelocationKind::Got, RelocationEncoding::Generic, 32) => {
+ elf::R_390_GOT32
+ }
+ (RelocationKind::Got, RelocationEncoding::Generic, 64) => {
+ elf::R_390_GOT64
+ }
+ (RelocationKind::GotRelative, RelocationEncoding::S390xDbl, 32) => {
+ elf::R_390_GOTENT
+ }
+ (RelocationKind::GotBaseOffset, RelocationEncoding::Generic, 16) => {
+ elf::R_390_GOTOFF16
+ }
+ (RelocationKind::GotBaseOffset, RelocationEncoding::Generic, 32) => {
+ elf::R_390_GOTOFF32
+ }
+ (RelocationKind::GotBaseOffset, RelocationEncoding::Generic, 64) => {
+ elf::R_390_GOTOFF64
+ }
+ (RelocationKind::GotBaseRelative, RelocationEncoding::Generic, 64) => {
+ elf::R_390_GOTPC
+ }
+ (RelocationKind::GotBaseRelative, RelocationEncoding::S390xDbl, 32) => {
+ elf::R_390_GOTPCDBL
+ }
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::Sbf => match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, _, 64) => elf::R_SBF_64_64,
+ (RelocationKind::Absolute, _, 32) => elf::R_SBF_64_32,
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::Sparc64 => match (reloc.kind, reloc.encoding, reloc.size) {
+ // TODO: use R_SPARC_32/R_SPARC_64 if aligned.
+ (RelocationKind::Absolute, _, 32) => elf::R_SPARC_UA32,
+ (RelocationKind::Absolute, _, 64) => elf::R_SPARC_UA64,
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ Architecture::Xtensa => match (reloc.kind, reloc.encoding, reloc.size) {
+ (RelocationKind::Absolute, _, 32) => elf::R_XTENSA_32,
+ (RelocationKind::Relative, RelocationEncoding::Generic, 32) => {
+ elf::R_XTENSA_32_PCREL
+ }
+ (RelocationKind::Elf(x), _, _) => x,
+ _ => {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ },
+ _ => {
+ if let RelocationKind::Elf(x) = reloc.kind {
+ x
+ } else {
+ return Err(Error(format!("unimplemented relocation {:?}", reloc)));
+ }
+ }
+ };
+ let r_sym = symbol_offsets[reloc.symbol.0].index.0;
+ writer.write_relocation(
+ is_rela,
+ &Rel {
+ r_offset: reloc.offset,
+ r_sym,
+ r_type,
+ r_addend: reloc.addend,
+ },
+ );
+ }
+ }
+ }
+
+ writer.write_shstrtab();
+
+ // Write section headers.
+ writer.write_null_section_header();
+
+ let symtab_index = writer.symtab_index();
+ for (comdat, comdat_offset) in self.comdats.iter().zip(comdat_offsets.iter()) {
+ writer.write_comdat_section_header(
+ comdat_offset.str_id,
+ symtab_index,
+ symbol_offsets[comdat.symbol.0].index,
+ comdat_offset.offset,
+ comdat.sections.len(),
+ );
+ }
+ for (index, section) in self.sections.iter().enumerate() {
+ let sh_type = match section.kind {
+ SectionKind::UninitializedData | SectionKind::UninitializedTls => elf::SHT_NOBITS,
+ SectionKind::Note => elf::SHT_NOTE,
+ SectionKind::Elf(sh_type) => sh_type,
+ _ => elf::SHT_PROGBITS,
+ };
+ let sh_flags = if let SectionFlags::Elf { sh_flags } = section.flags {
+ sh_flags
+ } else {
+ match section.kind {
+ SectionKind::Text => elf::SHF_ALLOC | elf::SHF_EXECINSTR,
+ SectionKind::Data | SectionKind::ReadOnlyDataWithRel => {
+ elf::SHF_ALLOC | elf::SHF_WRITE
+ }
+ SectionKind::Tls => elf::SHF_ALLOC | elf::SHF_WRITE | elf::SHF_TLS,
+ SectionKind::UninitializedData => elf::SHF_ALLOC | elf::SHF_WRITE,
+ SectionKind::UninitializedTls => elf::SHF_ALLOC | elf::SHF_WRITE | elf::SHF_TLS,
+ SectionKind::ReadOnlyData => elf::SHF_ALLOC,
+ SectionKind::ReadOnlyString => {
+ elf::SHF_ALLOC | elf::SHF_STRINGS | elf::SHF_MERGE
+ }
+ SectionKind::OtherString => elf::SHF_STRINGS | elf::SHF_MERGE,
+ SectionKind::Other
+ | SectionKind::Debug
+ | SectionKind::Metadata
+ | SectionKind::Linker
+ | SectionKind::Note
+ | SectionKind::Elf(_) => 0,
+ SectionKind::Unknown | SectionKind::Common | SectionKind::TlsVariables => {
+ return Err(Error(format!(
+ "unimplemented section `{}` kind {:?}",
+ section.name().unwrap_or(""),
+ section.kind
+ )));
+ }
+ }
+ .into()
+ };
+ // TODO: not sure if this is correct, maybe user should determine this
+ let sh_entsize = match section.kind {
+ SectionKind::ReadOnlyString | SectionKind::OtherString => 1,
+ _ => 0,
+ };
+ writer.write_section_header(&SectionHeader {
+ name: Some(section_offsets[index].str_id),
+ sh_type,
+ sh_flags,
+ sh_addr: 0,
+ sh_offset: section_offsets[index].offset as u64,
+ sh_size: section.size,
+ sh_link: 0,
+ sh_info: 0,
+ sh_addralign: section.align,
+ sh_entsize,
+ });
+
+ if !section.relocations.is_empty() {
+ writer.write_relocation_section_header(
+ section_offsets[index].reloc_str_id.unwrap(),
+ section_offsets[index].index,
+ symtab_index,
+ section_offsets[index].reloc_offset,
+ section.relocations.len(),
+ is_rela,
+ );
+ }
+ }
+
+ writer.write_symtab_section_header(symtab_num_local);
+ writer.write_symtab_shndx_section_header();
+ writer.write_strtab_section_header();
+ writer.write_shstrtab_section_header();
+
+ debug_assert_eq!(writer.reserved_len(), writer.len());
+
+ Ok(())
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-15 04:31:45 +0000