roc/crates/compiler/gen_dev/src/object_builder.rs
2023-09-14 11:51:03 +02:00

872 lines
30 KiB
Rust

use crate::generic64::{aarch64, new_backend_64bit, x86_64};
use crate::{AssemblyBackendMode, Backend, Env, Relocation};
use bumpalo::collections::Vec;
use object::write::{self, SectionId, SymbolId};
use object::write::{Object, StandardSection, StandardSegment, Symbol, SymbolSection};
use object::{
Architecture, BinaryFormat, Endianness, RelocationEncoding, RelocationKind, SectionKind,
SymbolFlags, SymbolKind, SymbolScope,
};
use roc_collections::all::MutMap;
use roc_error_macros::internal_error;
use roc_module::symbol;
use roc_module::symbol::Interns;
use roc_mono::ir::{Call, CallSpecId, Expr, UpdateModeId};
use roc_mono::ir::{Proc, ProcLayout, Stmt};
use roc_mono::layout::{LambdaName, Layout, LayoutIds, LayoutInterner, STLayoutInterner};
use roc_target::TargetInfo;
use target_lexicon::{Architecture as TargetArch, BinaryFormat as TargetBF, Triple};
// This is used by some code below which is currently commented out.
// See that code for more details!
// const VERSION: &str = env!("CARGO_PKG_VERSION");
/// build_module is the high level builder/delegator.
/// It takes the request to build a module and output the object file for the module.
pub fn build_module<'a, 'r>(
env: &'r Env<'a>,
interns: &'r mut Interns,
layout_interner: &'r mut STLayoutInterner<'a>,
target: &Triple,
procedures: MutMap<(symbol::Symbol, ProcLayout<'a>), Proc<'a>>,
) -> Object<'a> {
match target {
Triple {
architecture: TargetArch::X86_64,
binary_format: TargetBF::Elf,
..
} if cfg!(feature = "target-x86_64") => {
let backend = new_backend_64bit::<
x86_64::X86_64GeneralReg,
x86_64::X86_64FloatReg,
x86_64::X86_64Assembler,
x86_64::X86_64SystemV,
>(env, TargetInfo::default_x86_64(), interns, layout_interner);
// Newer version of `ld` require `.note.GNU-stack` for security reasons.
// It specifies that we will not execute code stored on the stack.
let mut object =
Object::new(BinaryFormat::Elf, Architecture::X86_64, Endianness::Little);
object.add_section(
vec![],
b".note.GNU-stack".to_vec(),
SectionKind::Elf(object::elf::SHT_PROGBITS),
);
build_object(env.mode, procedures, backend, object)
}
Triple {
architecture: TargetArch::X86_64,
binary_format: TargetBF::Macho,
..
} if cfg!(feature = "target-x86_64") => {
let backend = new_backend_64bit::<
x86_64::X86_64GeneralReg,
x86_64::X86_64FloatReg,
x86_64::X86_64Assembler,
x86_64::X86_64SystemV,
>(env, TargetInfo::default_x86_64(), interns, layout_interner);
build_object(
env.mode,
procedures,
backend,
Object::new(
BinaryFormat::MachO,
Architecture::X86_64,
Endianness::Little,
),
)
}
Triple {
architecture: TargetArch::X86_64,
binary_format: TargetBF::Coff,
..
} if cfg!(feature = "target-x86_64") => {
let backend = new_backend_64bit::<
x86_64::X86_64GeneralReg,
x86_64::X86_64FloatReg,
x86_64::X86_64Assembler,
x86_64::X86_64WindowsFastcall,
>(env, TargetInfo::default_x86_64(), interns, layout_interner);
build_object(
env.mode,
procedures,
backend,
Object::new(BinaryFormat::Coff, Architecture::X86_64, Endianness::Little),
)
}
Triple {
architecture: TargetArch::Aarch64(_),
binary_format: TargetBF::Elf,
..
} if cfg!(feature = "target-aarch64") => {
let backend =
new_backend_64bit::<
aarch64::AArch64GeneralReg,
aarch64::AArch64FloatReg,
aarch64::AArch64Assembler,
aarch64::AArch64Call,
>(env, TargetInfo::default_aarch64(), interns, layout_interner);
build_object(
env.mode,
procedures,
backend,
Object::new(BinaryFormat::Elf, Architecture::Aarch64, Endianness::Little),
)
}
Triple {
architecture: TargetArch::Aarch64(_),
binary_format: TargetBF::Macho,
..
} if cfg!(feature = "target-aarch64") => {
let backend =
new_backend_64bit::<
aarch64::AArch64GeneralReg,
aarch64::AArch64FloatReg,
aarch64::AArch64Assembler,
aarch64::AArch64Call,
>(env, TargetInfo::default_aarch64(), interns, layout_interner);
build_object(
env.mode,
procedures,
backend,
Object::new(
BinaryFormat::MachO,
Architecture::Aarch64,
Endianness::Little,
),
)
}
x => unimplemented!("the target, {:?}", x),
}
}
fn define_setlongjmp_buffer(output: &mut Object) -> SymbolId {
let bss_section = output.section_id(StandardSection::Data);
// 8 registers + 3 words for a RocStr
// TODO 50 is the wrong size here, look at implementation and put correct value in here
const SIZE: usize = (8 + 50) * core::mem::size_of::<u64>();
let symbol = Symbol {
name: b"setlongjmp_buffer".to_vec(),
value: 0,
size: SIZE as u64,
kind: SymbolKind::Data,
scope: SymbolScope::Dynamic,
weak: false,
section: SymbolSection::Section(bss_section),
flags: SymbolFlags::None,
};
let symbol_id = output.add_symbol(symbol);
output.add_symbol_data(symbol_id, bss_section, &[0x00; SIZE], 8);
symbol_id
}
fn generate_setjmp<'a, B: Backend<'a>>(backend: &mut B, output: &mut Object) {
let text_section = output.section_id(StandardSection::Text);
let proc_symbol = Symbol {
name: b"roc_setjmp".to_vec(),
value: 0,
size: 0,
kind: SymbolKind::Text,
scope: SymbolScope::Dynamic,
weak: false,
section: SymbolSection::Section(text_section),
flags: SymbolFlags::None,
};
let proc_id = output.add_symbol(proc_symbol);
let proc_data = backend.build_roc_setjmp();
output.add_symbol_data(proc_id, text_section, proc_data, 16);
}
fn generate_longjmp<'a, B: Backend<'a>>(backend: &mut B, output: &mut Object) {
let text_section = output.section_id(StandardSection::Text);
let proc_symbol = Symbol {
name: b"roc_longjmp".to_vec(),
value: 0,
size: 0,
kind: SymbolKind::Text,
scope: SymbolScope::Dynamic,
weak: false,
section: SymbolSection::Section(text_section),
flags: SymbolFlags::None,
};
let proc_id = output.add_symbol(proc_symbol);
let proc_data = backend.build_roc_longjmp();
output.add_symbol_data(proc_id, text_section, proc_data, 16);
}
// a roc_panic to be used in tests; relies on setjmp/longjmp
fn generate_roc_panic<'a, B: Backend<'a>>(backend: &mut B, output: &mut Object) {
let text_section = output.section_id(StandardSection::Text);
let proc_symbol = Symbol {
name: b"roc_panic".to_vec(),
value: 0,
size: 0,
kind: SymbolKind::Text,
scope: SymbolScope::Dynamic,
weak: false,
section: SymbolSection::Section(text_section),
flags: SymbolFlags::None,
};
let proc_id = output.add_symbol(proc_symbol);
let (proc_data, relocs) = backend.build_roc_panic();
let proc_offset = output.add_symbol_data(proc_id, text_section, proc_data, 16);
for r in relocs {
let relocation = match r {
Relocation::LinkedData { offset, name } => {
if let Some(sym_id) = output.symbol_id(name.as_bytes()) {
write::Relocation {
offset: offset + proc_offset,
size: 32,
kind: RelocationKind::GotRelative,
encoding: RelocationEncoding::Generic,
symbol: sym_id,
addend: -4,
}
} else {
internal_error!("failed to find data symbol for {:?}", name);
}
}
Relocation::LocalData { .. }
| Relocation::LinkedFunction { .. }
| Relocation::JmpToReturn { .. } => {
unreachable!("not currently created by build_roc_panic")
}
};
output.add_relocation(text_section, relocation).unwrap();
}
}
fn generate_wrapper<'a, B: Backend<'a>>(
backend: &mut B,
output: &mut Object,
wrapper_name: String,
wraps: String,
) {
let text_section = output.section_id(StandardSection::Text);
let proc_symbol = Symbol {
name: wrapper_name.as_bytes().to_vec(),
value: 0,
size: 0,
kind: SymbolKind::Text,
scope: SymbolScope::Dynamic,
weak: false,
section: SymbolSection::Section(text_section),
flags: SymbolFlags::None,
};
let proc_id = output.add_symbol(proc_symbol);
let (proc_data, offset) = backend.build_wrapped_jmp();
let proc_offset = output.add_symbol_data(proc_id, text_section, proc_data, 16);
let name = wraps.as_str().as_bytes();
// If the symbol is an undefined zig builtin, we need to add it here.
let symbol = Symbol {
name: name.to_vec(),
value: 0,
size: 0,
kind: SymbolKind::Text,
scope: SymbolScope::Dynamic,
weak: true,
section: SymbolSection::Undefined,
flags: SymbolFlags::None,
};
output.add_symbol(symbol);
if let Some(sym_id) = output.symbol_id(name) {
let reloc = write::Relocation {
offset: offset + proc_offset,
size: 32,
kind: RelocationKind::PltRelative,
encoding: RelocationEncoding::X86Branch,
symbol: sym_id,
addend: -4,
};
match output.add_relocation(text_section, reloc) {
Ok(obj) => obj,
Err(e) => internal_error!("{:?}", e),
}
} else {
internal_error!("failed to find fn symbol for {:?}", wraps);
}
}
fn build_object<'a, B: Backend<'a>>(
mode: AssemblyBackendMode,
procedures: MutMap<(symbol::Symbol, ProcLayout<'a>), Proc<'a>>,
mut backend: B,
mut output: Object<'a>,
) -> Object<'a> {
let data_section = output.section_id(StandardSection::Data);
let arena = backend.env().arena;
/*
// Commented out because we couldn't figure out how to get it to work on mac - see https://github.com/roc-lang/roc/pull/1323
let comment = output.add_section(vec![], b".comment".to_vec(), SectionKind::OtherString);
output.append_section_data(
comment,
format!("\0roc dev backend version {} \0", VERSION).as_bytes(),
1,
);
*/
if backend.env().mode.generate_roc_panic() {
define_setlongjmp_buffer(&mut output);
generate_roc_panic(&mut backend, &mut output);
generate_setjmp(&mut backend, &mut output);
generate_longjmp(&mut backend, &mut output);
}
if backend.env().mode.generate_allocators() {
generate_wrapper(
&mut backend,
&mut output,
"roc_alloc".into(),
"malloc".into(),
);
generate_wrapper(
&mut backend,
&mut output,
"roc_realloc".into(),
"realloc".into(),
);
generate_wrapper(
&mut backend,
&mut output,
"roc_dealloc".into(),
"free".into(),
);
// Extra symbols only required on unix systems.
if matches!(output.format(), BinaryFormat::Elf | BinaryFormat::MachO) {
generate_wrapper(
&mut backend,
&mut output,
"roc_getppid".into(),
"getppid".into(),
);
generate_wrapper(&mut backend, &mut output, "roc_mmap".into(), "mmap".into());
generate_wrapper(
&mut backend,
&mut output,
"roc_shm_open".into(),
"shm_open".into(),
);
} else if matches!(output.format(), BinaryFormat::Coff) {
// TODO figure out why this symbol is required, it should not be required
// Without this it does not build on Windows
generate_wrapper(
&mut backend,
&mut output,
"roc_getppid".into(),
"malloc".into(),
);
}
}
// Setup layout_ids for procedure calls.
let mut layout_ids = LayoutIds::default();
let mut procs = Vec::with_capacity_in(procedures.len(), arena);
// Names and linker data for user procedures
for ((sym, layout), proc) in procedures {
debug_assert_eq!(sym, proc.name.name());
if backend.env().exposed_to_host.contains(&sym) {
let exposed_proc = build_exposed_proc(&mut backend, &proc);
let exposed_generic_proc = build_exposed_generic_proc(&mut backend, &proc);
let (module_id, layout_interner, interns, code_gen_help, _) =
backend.module_interns_helpers_mut();
let ident_ids = interns.all_ident_ids.get_mut(&module_id).unwrap();
let test_helper = roc_mono::code_gen_help::test_helper(
code_gen_help,
ident_ids,
layout_interner,
&proc,
);
#[cfg(debug_assertions)]
{
let module_id = exposed_generic_proc.name.name().module_id();
let ident_ids = backend
.interns_mut()
.all_ident_ids
.get_mut(&module_id)
.unwrap();
module_id.register_debug_idents(ident_ids);
}
if let AssemblyBackendMode::Test = mode {
if false {
println!("{}", test_helper.to_pretty(backend.interner(), 200, true));
}
build_proc_symbol(
&mut output,
&mut layout_ids,
&mut procs,
&mut backend,
layout,
test_helper,
Exposed::TestMain,
);
}
build_proc_symbol(
&mut output,
&mut layout_ids,
&mut procs,
&mut backend,
layout,
exposed_proc,
Exposed::Exposed,
);
build_proc_symbol(
&mut output,
&mut layout_ids,
&mut procs,
&mut backend,
layout,
exposed_generic_proc,
Exposed::ExposedGeneric,
);
}
build_proc_symbol(
&mut output,
&mut layout_ids,
&mut procs,
&mut backend,
layout,
proc,
Exposed::NotExposed,
)
}
// Build procedures from user code
let mut relocations = bumpalo::vec![in arena];
for (fn_name, section_id, proc_id, proc) in procs {
build_proc(
&mut output,
&mut backend,
&mut relocations,
&mut layout_ids,
data_section,
fn_name,
section_id,
proc_id,
proc,
)
}
// Generate IR for specialized helper procs (refcounting & equality)
let empty = bumpalo::collections::Vec::new_in(arena);
let mut helper_symbols_and_layouts =
std::mem::replace(backend.helper_proc_symbols_mut(), empty);
let helper_procs = {
let (module_id, _interner, interns, helper_proc_gen, caller_procs) =
backend.module_interns_helpers_mut();
let mut owned_caller_procs = bumpalo::collections::Vec::new_in(arena);
std::mem::swap(caller_procs, &mut owned_caller_procs);
let ident_ids = interns.all_ident_ids.get_mut(&module_id).unwrap();
let mut helper_procs = helper_proc_gen.take_procs();
for caller_proc in owned_caller_procs {
helper_symbols_and_layouts.push((caller_proc.proc_symbol, caller_proc.proc_layout));
helper_procs.push(caller_proc.proc);
}
if false {
module_id.register_debug_idents(ident_ids);
for p in &helper_procs {
println!("{}", p.to_pretty(_interner, 200, true));
}
}
helper_procs
};
let mut helper_names_symbols_procs = Vec::with_capacity_in(helper_procs.len(), arena);
debug_assert_eq!(helper_symbols_and_layouts.len(), helper_procs.len());
// Names and linker data for helpers
for ((sym, layout), proc) in helper_symbols_and_layouts.into_iter().zip(helper_procs) {
debug_assert_eq!(sym, proc.name.name());
let fn_name = backend.lambda_name_to_string(
LambdaName::no_niche(sym),
layout.arguments.iter().copied(),
None,
layout.result,
);
if let Some(proc_id) = output.symbol_id(fn_name.as_bytes()) {
if let SymbolSection::Section(section_id) = output.symbol(proc_id).section {
helper_names_symbols_procs.push((fn_name, section_id, proc_id, proc));
continue;
}
} else {
// The symbol isn't defined yet and will just be used by other rc procs.
let section_id = output.add_section(
output.segment_name(StandardSegment::Text).to_vec(),
format!(".text.{:x}", sym.as_u64()).as_bytes().to_vec(),
SectionKind::Text,
);
let rc_symbol = Symbol {
name: fn_name.as_bytes().to_vec(),
value: 0,
size: 0,
kind: SymbolKind::Text,
scope: SymbolScope::Linkage,
weak: false,
section: SymbolSection::Section(section_id),
flags: SymbolFlags::None,
};
let proc_id = output.add_symbol(rc_symbol);
helper_names_symbols_procs.push((fn_name, section_id, proc_id, proc));
continue;
}
internal_error!("failed to create rc fn for symbol {:?}", sym);
}
// Build helpers
for (fn_name, section_id, proc_id, proc) in helper_names_symbols_procs {
build_proc(
&mut output,
&mut backend,
&mut relocations,
&mut layout_ids,
data_section,
fn_name,
section_id,
proc_id,
proc,
)
}
// Relocations for all procedures (user code & helpers)
for (section_id, reloc) in relocations {
match output.add_relocation(section_id, reloc) {
Ok(obj) => obj,
Err(e) => internal_error!("{:?}", e),
}
}
output
}
fn build_exposed_proc<'a, B: Backend<'a>>(backend: &mut B, proc: &Proc<'a>) -> Proc<'a> {
let arena = backend.env().arena;
let interns = backend.interns();
let sym = proc.name.name();
let platform = sym.module_id();
let fn_name = sym.as_str(interns).to_string();
let generic_proc_name = backend.debug_symbol_in(platform, &fn_name);
let s4 = backend.debug_symbol_in(platform, "s4");
let call_args = bumpalo::collections::Vec::from_iter_in(proc.args.iter().map(|t| t.1), arena);
let call_layouts =
bumpalo::collections::Vec::from_iter_in(proc.args.iter().map(|t| t.0), arena);
let call = Call {
call_type: roc_mono::ir::CallType::ByName {
name: proc.name,
ret_layout: proc.ret_layout,
arg_layouts: call_layouts.into_bump_slice(),
specialization_id: CallSpecId::BACKEND_DUMMY,
},
arguments: call_args.into_bump_slice(),
};
let body = Stmt::Let(
s4,
Expr::Call(call),
proc.ret_layout,
arena.alloc(Stmt::Ret(s4)),
);
Proc {
name: LambdaName::no_niche(generic_proc_name),
args: proc.args,
body,
closure_data_layout: None,
ret_layout: proc.ret_layout,
is_self_recursive: roc_mono::ir::SelfRecursive::NotSelfRecursive,
is_erased: proc.is_erased,
}
}
fn build_exposed_generic_proc<'a, B: Backend<'a>>(backend: &mut B, proc: &Proc<'a>) -> Proc<'a> {
let arena = backend.env().arena;
let interns = backend.interns();
let sym = proc.name.name();
let platform = sym.module_id();
let fn_name = sym.as_str(interns).to_string();
let generic_proc_name = backend.debug_symbol_in(platform, &fn_name);
let arg_generic = backend.debug_symbol_in(platform, "arg_generic");
let s1 = backend.debug_symbol_in(platform, "s1");
let s2 = backend.debug_symbol_in(platform, "s2");
let s3 = backend.debug_symbol_in(platform, "s3");
let box_layout = backend
.interner_mut()
.insert_direct_no_semantic(roc_mono::layout::LayoutRepr::Ptr(proc.ret_layout));
let mut args = bumpalo::collections::Vec::new_in(arena);
args.extend(proc.args);
args.push((box_layout, arg_generic));
let call_args = bumpalo::collections::Vec::from_iter_in(proc.args.iter().map(|t| t.1), arena);
let call_layouts =
bumpalo::collections::Vec::from_iter_in(proc.args.iter().map(|t| t.0), arena);
let call = Call {
call_type: roc_mono::ir::CallType::ByName {
name: proc.name,
ret_layout: proc.ret_layout,
arg_layouts: call_layouts.into_bump_slice(),
specialization_id: CallSpecId::BACKEND_DUMMY,
},
arguments: call_args.into_bump_slice(),
};
let box_write = Call {
call_type: roc_mono::ir::CallType::LowLevel {
op: roc_module::low_level::LowLevel::PtrStore,
update_mode: UpdateModeId::BACKEND_DUMMY,
},
arguments: arena.alloc([arg_generic, s1]),
};
let body = Stmt::Let(
s1,
Expr::Call(call),
proc.ret_layout,
arena.alloc(
//
Stmt::Let(
s2,
Expr::Call(box_write),
box_layout,
arena.alloc(
//
Stmt::Let(
s3,
Expr::Struct(&[]),
Layout::UNIT,
arena.alloc(
//
Stmt::Ret(s3),
),
),
),
),
),
);
Proc {
name: LambdaName::no_niche(generic_proc_name),
args: args.into_bump_slice(),
body,
closure_data_layout: None,
ret_layout: roc_mono::layout::Layout::UNIT,
is_self_recursive: roc_mono::ir::SelfRecursive::NotSelfRecursive,
is_erased: proc.is_erased,
}
}
#[allow(clippy::enum_variant_names)]
enum Exposed {
ExposedGeneric,
Exposed,
NotExposed,
TestMain,
}
fn build_proc_symbol<'a, B: Backend<'a>>(
output: &mut Object<'a>,
layout_ids: &mut LayoutIds<'a>,
procs: &mut Vec<'a, (String, SectionId, SymbolId, Proc<'a>)>,
backend: &mut B,
layout: ProcLayout<'a>,
proc: Proc<'a>,
exposed: Exposed,
) {
let sym = proc.name.name();
let section_id = output.add_section(
output.segment_name(StandardSegment::Text).to_vec(),
format!(".text.{:x}", sym.as_u64()).as_bytes().to_vec(),
SectionKind::Text,
);
let fn_name = match exposed {
Exposed::ExposedGeneric => layout_ids
.get_toplevel(sym, &layout)
.to_exposed_generic_symbol_string(sym, backend.interns()),
Exposed::Exposed => layout_ids
.get_toplevel(sym, &layout)
.to_exposed_symbol_string(sym, backend.interns()),
Exposed::NotExposed => backend.lambda_name_to_string(
proc.name,
layout.arguments.iter().copied(),
None,
layout.result,
),
Exposed::TestMain => String::from("test_main"),
};
let proc_symbol = Symbol {
name: fn_name.as_bytes().to_vec(),
value: 0,
size: 0,
kind: SymbolKind::Text,
// TODO: Depending on whether we are building a static or dynamic lib, this should change.
// We should use Dynamic -> anyone, Linkage -> static link, Compilation -> this module only.
scope: match exposed {
Exposed::ExposedGeneric | Exposed::Exposed | Exposed::TestMain => SymbolScope::Dynamic,
Exposed::NotExposed => SymbolScope::Linkage,
},
weak: false,
section: SymbolSection::Section(section_id),
flags: SymbolFlags::None,
};
let proc_id = output.add_symbol(proc_symbol);
procs.push((fn_name, section_id, proc_id, proc));
}
#[allow(clippy::too_many_arguments)]
fn build_proc<'a, B: Backend<'a>>(
output: &mut Object,
backend: &mut B,
relocations: &mut Vec<'a, (SectionId, object::write::Relocation)>,
layout_ids: &mut LayoutIds<'a>,
data_section: SectionId,
fn_name: String,
section_id: SectionId,
proc_id: SymbolId,
proc: Proc<'a>,
) {
let mut local_data_index = 0;
let (proc_data, relocs, rc_proc_names) = backend.build_proc(proc, layout_ids);
let proc_offset = output.add_symbol_data(proc_id, section_id, &proc_data, 16);
for reloc in relocs.iter() {
let elfreloc = match reloc {
Relocation::LocalData { offset, data } => {
let data_symbol = write::Symbol {
name: format!("{fn_name}.data{local_data_index}")
.as_bytes()
.to_vec(),
value: 0,
size: 0,
kind: SymbolKind::Data,
scope: SymbolScope::Compilation,
weak: false,
section: SymbolSection::Section(data_section),
flags: SymbolFlags::None,
};
local_data_index += 1;
let data_id = output.add_symbol(data_symbol);
output.add_symbol_data(data_id, data_section, data, 4);
write::Relocation {
offset: offset + proc_offset,
size: 32,
kind: RelocationKind::Relative,
encoding: RelocationEncoding::Generic,
symbol: data_id,
addend: -4,
}
}
Relocation::LinkedData { offset, name } => {
if let Some(sym_id) = output.symbol_id(name.as_bytes()) {
write::Relocation {
offset: offset + proc_offset,
size: 32,
kind: RelocationKind::GotRelative,
encoding: RelocationEncoding::Generic,
symbol: sym_id,
addend: -4,
}
} else {
internal_error!("failed to find data symbol for {:?}", name);
}
}
Relocation::LinkedFunction { offset, name } => {
// If the symbol is an undefined roc function, we need to add it here.
if output.symbol_id(name.as_bytes()).is_none() && name.starts_with("roc_") {
let builtin_symbol = Symbol {
name: name.as_bytes().to_vec(),
value: 0,
size: 0,
kind: SymbolKind::Text,
scope: SymbolScope::Linkage,
weak: false,
section: SymbolSection::Undefined,
flags: SymbolFlags::None,
};
output.add_symbol(builtin_symbol);
}
// If the symbol is an undefined reference counting procedure, we need to add it here.
if output.symbol_id(name.as_bytes()).is_none() {
for (sym, rc_name) in rc_proc_names.iter() {
if name == rc_name {
let section_id = output.add_section(
output.segment_name(StandardSegment::Text).to_vec(),
format!(".text.{:x}", sym.as_u64()).as_bytes().to_vec(),
SectionKind::Text,
);
let rc_symbol = Symbol {
name: name.as_bytes().to_vec(),
value: 0,
size: 0,
kind: SymbolKind::Text,
scope: SymbolScope::Linkage,
weak: false,
section: SymbolSection::Section(section_id),
flags: SymbolFlags::None,
};
output.add_symbol(rc_symbol);
}
}
}
if let Some(sym_id) = output.symbol_id(name.as_bytes()) {
write::Relocation {
offset: offset + proc_offset,
size: 32,
kind: RelocationKind::PltRelative,
encoding: RelocationEncoding::X86Branch,
symbol: sym_id,
addend: -4,
}
} else {
internal_error!("failed to find fn symbol for {:?}", name);
}
}
Relocation::JmpToReturn { .. } => unreachable!(),
};
relocations.push((section_id, elfreloc));
}
}