+//! Abstraction around the object writing crate
+
use std::convert::{TryFrom, TryInto};
use rustc_data_structures::fx::FxHashMap;
use rustc_session::Session;
-use cranelift_module::{FuncId, Module};
+use cranelift_codegen::isa::TargetIsa;
+use cranelift_module::FuncId;
+use cranelift_object::{ObjectBuilder, ObjectModule, ObjectProduct};
use object::write::*;
-use object::{RelocationEncoding, RelocationKind, SectionKind, SymbolFlags};
-
-use cranelift_object::{ObjectBackend, ObjectBuilder, ObjectProduct};
+use object::{RelocationEncoding, SectionKind, SymbolFlags};
use gimli::SectionId;
use crate::debuginfo::{DebugReloc, DebugRelocName};
pub(crate) trait WriteMetadata {
- fn add_rustc_section(&mut self, symbol_name: String, data: Vec<u8>, is_like_osx: bool);
+ fn add_rustc_section(&mut self, symbol_name: String, data: Vec<u8>);
}
impl WriteMetadata for object::write::Object {
- fn add_rustc_section(&mut self, symbol_name: String, data: Vec<u8>, _is_like_osx: bool) {
- let segment = self
- .segment_name(object::write::StandardSegment::Data)
- .to_vec();
+ fn add_rustc_section(&mut self, symbol_name: String, data: Vec<u8>) {
+ let segment = self.segment_name(object::write::StandardSegment::Data).to_vec();
let section_id = self.add_section(segment, b".rustc".to_vec(), object::SectionKind::Data);
let offset = self.append_section_data(section_id, &data, 1);
// For MachO and probably PE this is necessary to prevent the linker from throwing away the
.into_bytes();
let segment = self.object.segment_name(StandardSegment::Debug).to_vec();
- let section_id = self.object.add_section(segment, name, SectionKind::Debug);
- self.object.section_mut(section_id).set_data(data, 1);
+ // FIXME use SHT_X86_64_UNWIND for .eh_frame
+ let section_id = self.object.add_section(
+ segment,
+ name,
+ if id == SectionId::EhFrame { SectionKind::ReadOnlyData } else { SectionKind::Debug },
+ );
+ self.object
+ .section_mut(section_id)
+ .set_data(data, if id == SectionId::EhFrame { 8 } else { 1 });
let symbol_id = self.object.section_symbol(section_id);
(section_id, symbol_id)
}
Relocation {
offset: u64::from(reloc.offset),
symbol,
- kind: RelocationKind::Absolute,
+ kind: reloc.kind,
encoding: RelocationEncoding::Generic,
size: reloc.size * 8,
addend: i64::try_from(symbol_offset).unwrap() + reloc.addend,
}
}
-// FIXME remove once atomic instructions are implemented in Cranelift.
-pub(crate) trait AddConstructor {
- fn add_constructor(&mut self, func_id: FuncId);
-}
-
-impl AddConstructor for ObjectProduct {
- fn add_constructor(&mut self, func_id: FuncId) {
- let symbol = self.function_symbol(func_id);
- let segment = self
- .object
- .segment_name(object::write::StandardSegment::Data);
- let init_array_section =
- self.object
- .add_section(segment.to_vec(), b".init_array".to_vec(), SectionKind::Data);
- self.object.append_section_data(
- init_array_section,
- &std::iter::repeat(0)
- .take(8 /*FIXME pointer size*/)
- .collect::<Vec<u8>>(),
- 8,
- );
- self.object
- .add_relocation(
- init_array_section,
- object::write::Relocation {
- offset: 0,
- size: 64, // FIXME pointer size
- kind: RelocationKind::Absolute,
- encoding: RelocationEncoding::Generic,
- symbol,
- addend: 0,
- },
- )
- .unwrap();
- }
-}
-
-pub(crate) trait Emit {
- fn emit(self) -> Vec<u8>;
-}
-
-impl Emit for ObjectProduct {
- fn emit(self) -> Vec<u8> {
- self.object.write().unwrap()
- }
-}
-
pub(crate) fn with_object(sess: &Session, name: &str, f: impl FnOnce(&mut Object)) -> Vec<u8> {
- let triple = crate::build_isa(sess, true).triple().clone();
+ let triple = crate::target_triple(sess);
let binary_format = match triple.binary_format {
target_lexicon::BinaryFormat::Elf => object::BinaryFormat::Elf,
target_lexicon::Architecture::X86_64 => object::Architecture::X86_64,
target_lexicon::Architecture::Arm(_) => object::Architecture::Arm,
target_lexicon::Architecture::Aarch64(_) => object::Architecture::Aarch64,
- architecture => sess.fatal(&format!(
- "target architecture {:?} is unsupported",
- architecture,
- )),
+ architecture => {
+ sess.fatal(&format!("target architecture {:?} is unsupported", architecture,))
+ }
};
let endian = match triple.endianness().unwrap() {
target_lexicon::Endianness::Little => object::Endianness::Little,
metadata_object.write().unwrap()
}
-pub(crate) type Backend =
- impl cranelift_module::Backend<Product: AddConstructor + Emit + WriteDebugInfo>;
-
-pub(crate) fn make_module(sess: &Session, name: String) -> Module<Backend> {
- let mut builder = ObjectBuilder::new(
- crate::build_isa(sess, true),
- name + ".o",
- cranelift_module::default_libcall_names(),
- )
- .unwrap();
- if std::env::var("CG_CLIF_FUNCTION_SECTIONS").is_ok() {
- builder.per_function_section(true);
- }
- let module: Module<ObjectBackend> = Module::new(
- builder,
- );
- module
+pub(crate) fn make_module(sess: &Session, isa: Box<dyn TargetIsa>, name: String) -> ObjectModule {
+ let mut builder =
+ ObjectBuilder::new(isa, name + ".o", cranelift_module::default_libcall_names()).unwrap();
+ // Unlike cg_llvm, cg_clif defaults to disabling -Zfunction-sections. For cg_llvm binary size
+ // is important, while cg_clif cares more about compilation times. Enabling -Zfunction-sections
+ // can easily double the amount of time necessary to perform linking.
+ builder.per_function_section(sess.opts.debugging_opts.function_sections.unwrap_or(false));
+ ObjectModule::new(builder)
}
projects / rust.git / blobdiff