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write.rs
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use crate::attributes;
use crate::back::bytecode::{self, RLIB_BYTECODE_EXTENSION};
use crate::back::lto::ThinBuffer;
use crate::base;
use crate::consts;
use crate::llvm::{self, DiagnosticInfo, PassManager, SMDiagnostic};
use crate::llvm_util;
use crate::ModuleLlvm;
use crate::type_::Type;
use crate::context::{is_pie_binary, get_reloc_model};
use crate::common;
use crate::LlvmCodegenBackend;
use rustc::hir::def_id::LOCAL_CRATE;
use rustc_codegen_ssa::back::write::{CodegenContext, ModuleConfig, run_assembler};
use rustc_codegen_ssa::traits::*;
use rustc::session::config::{self, OutputType, Passes, Lto};
use rustc::session::Session;
use rustc::ty::TyCtxt;
use rustc_codegen_ssa::{ModuleCodegen, CompiledModule};
use rustc::util::common::time_ext;
use rustc::util::profiling::ProfileCategory;
use rustc_fs_util::{path_to_c_string, link_or_copy};
use rustc_data_structures::small_c_str::SmallCStr;
use errors::{Handler, FatalError};
use std::ffi::{CString, CStr};
use std::fs;
use std::io::{self, Write};
use std::path::Path;
use std::str;
use std::sync::Arc;
use std::slice;
use libc::{c_uint, c_void, c_char, size_t};
pub const RELOC_MODEL_ARGS : [(&str, llvm::RelocMode); 7] = [
("pic", llvm::RelocMode::PIC),
("static", llvm::RelocMode::Static),
("default", llvm::RelocMode::Default),
("dynamic-no-pic", llvm::RelocMode::DynamicNoPic),
("ropi", llvm::RelocMode::ROPI),
("rwpi", llvm::RelocMode::RWPI),
("ropi-rwpi", llvm::RelocMode::ROPI_RWPI),
];
pub const CODE_GEN_MODEL_ARGS: &[(&str, llvm::CodeModel)] = &[
("small", llvm::CodeModel::Small),
("kernel", llvm::CodeModel::Kernel),
("medium", llvm::CodeModel::Medium),
("large", llvm::CodeModel::Large),
];
pub const TLS_MODEL_ARGS : [(&str, llvm::ThreadLocalMode); 4] = [
("global-dynamic", llvm::ThreadLocalMode::GeneralDynamic),
("local-dynamic", llvm::ThreadLocalMode::LocalDynamic),
("initial-exec", llvm::ThreadLocalMode::InitialExec),
("local-exec", llvm::ThreadLocalMode::LocalExec),
];
pub fn llvm_err(handler: &errors::Handler, msg: &str) -> FatalError {
match llvm::last_error() {
Some(err) => handler.fatal(&format!("{}: {}", msg, err)),
None => handler.fatal(&msg),
}
}
pub fn write_output_file(
handler: &errors::Handler,
target: &'ll llvm::TargetMachine,
pm: &llvm::PassManager<'ll>,
m: &'ll llvm::Module,
output: &Path,
file_type: llvm::FileType) -> Result<(), FatalError> {
unsafe {
let output_c = path_to_c_string(output);
let result = llvm::LLVMRustWriteOutputFile(target, pm, m, output_c.as_ptr(), file_type);
result.into_result().map_err(|()| {
let msg = format!("could not write output to {}", output.display());
llvm_err(handler, &msg)
})
}
}
pub fn create_informational_target_machine(
sess: &Session,
find_features: bool,
) -> &'static mut llvm::TargetMachine {
target_machine_factory(sess, config::OptLevel::No, find_features)().unwrap_or_else(|err| {
llvm_err(sess.diagnostic(), &err).raise()
})
}
pub fn create_target_machine(
tcx: TyCtxt<'_, '_, '_>,
find_features: bool,
) -> &'static mut llvm::TargetMachine {
target_machine_factory(&tcx.sess, tcx.backend_optimization_level(LOCAL_CRATE), find_features)()
.unwrap_or_else(|err| {
llvm_err(tcx.sess.diagnostic(), &err).raise()
})
}
pub fn to_llvm_opt_settings(cfg: config::OptLevel) -> (llvm::CodeGenOptLevel, llvm::CodeGenOptSize)
{
use self::config::OptLevel::*;
match cfg {
No => (llvm::CodeGenOptLevel::None, llvm::CodeGenOptSizeNone),
Less => (llvm::CodeGenOptLevel::Less, llvm::CodeGenOptSizeNone),
Default => (llvm::CodeGenOptLevel::Default, llvm::CodeGenOptSizeNone),
Aggressive => (llvm::CodeGenOptLevel::Aggressive, llvm::CodeGenOptSizeNone),
Size => (llvm::CodeGenOptLevel::Default, llvm::CodeGenOptSizeDefault),
SizeMin => (llvm::CodeGenOptLevel::Default, llvm::CodeGenOptSizeAggressive),
}
}
// If find_features is true this won't access `sess.crate_types` by assuming
// that `is_pie_binary` is false. When we discover LLVM target features
// `sess.crate_types` is uninitialized so we cannot access it.
pub fn target_machine_factory(sess: &Session, optlvl: config::OptLevel, find_features: bool)
-> Arc<dyn Fn() -> Result<&'static mut llvm::TargetMachine, String> + Send + Sync>
{
let reloc_model = get_reloc_model(sess);
let (opt_level, _) = to_llvm_opt_settings(optlvl);
let use_softfp = sess.opts.cg.soft_float;
let ffunction_sections = sess.target.target.options.function_sections;
let fdata_sections = ffunction_sections;
let code_model_arg = sess.opts.cg.code_model.as_ref().or(
sess.target.target.options.code_model.as_ref(),
);
let code_model = match code_model_arg {
Some(s) => {
match CODE_GEN_MODEL_ARGS.iter().find(|arg| arg.0 == s) {
Some(x) => x.1,
_ => {
sess.err(&format!("{:?} is not a valid code model",
code_model_arg));
sess.abort_if_errors();
bug!();
}
}
}
None => llvm::CodeModel::None,
};
let features = attributes::llvm_target_features(sess).collect::<Vec<_>>();
let mut singlethread = sess.target.target.options.singlethread;
// On the wasm target once the `atomics` feature is enabled that means that
// we're no longer single-threaded, or otherwise we don't want LLVM to
// lower atomic operations to single-threaded operations.
if singlethread &&
sess.target.target.llvm_target.contains("wasm32") &&
features.iter().any(|s| *s == "+atomics")
{
singlethread = false;
}
let triple = SmallCStr::new(&sess.target.target.llvm_target);
let cpu = SmallCStr::new(llvm_util::target_cpu(sess));
let features = features.join(",");
let features = CString::new(features).unwrap();
let is_pie_binary = !find_features && is_pie_binary(sess);
let trap_unreachable = sess.target.target.options.trap_unreachable;
let emit_stack_size_section = sess.opts.debugging_opts.emit_stack_sizes;
let asm_comments = sess.asm_comments();
Arc::new(move || {
let tm = unsafe {
llvm::LLVMRustCreateTargetMachine(
triple.as_ptr(), cpu.as_ptr(), features.as_ptr(),
code_model,
reloc_model,
opt_level,
use_softfp,
is_pie_binary,
ffunction_sections,
fdata_sections,
trap_unreachable,
singlethread,
asm_comments,
emit_stack_size_section,
)
};
tm.ok_or_else(|| {
format!("Could not create LLVM TargetMachine for triple: {}",
triple.to_str().unwrap())
})
})
}
pub(crate) fn save_temp_bitcode(
cgcx: &CodegenContext<LlvmCodegenBackend>,
module: &ModuleCodegen<ModuleLlvm>,
name: &str
) {
if !cgcx.save_temps {
return
}
unsafe {
let ext = format!("{}.bc", name);
let cgu = Some(&module.name[..]);
let path = cgcx.output_filenames.temp_path_ext(&ext, cgu);
let cstr = path_to_c_string(&path);
let llmod = module.module_llvm.llmod();
llvm::LLVMWriteBitcodeToFile(llmod, cstr.as_ptr());
}
}
pub struct DiagnosticHandlers<'a> {
data: *mut (&'a CodegenContext<LlvmCodegenBackend>, &'a Handler),
llcx: &'a llvm::Context,
}
impl<'a> DiagnosticHandlers<'a> {
pub fn new(cgcx: &'a CodegenContext<LlvmCodegenBackend>,
handler: &'a Handler,
llcx: &'a llvm::Context) -> Self {
let data = Box::into_raw(Box::new((cgcx, handler)));
unsafe {
llvm::LLVMRustSetInlineAsmDiagnosticHandler(llcx, inline_asm_handler, data as *mut _);
llvm::LLVMContextSetDiagnosticHandler(llcx, diagnostic_handler, data as *mut _);
}
DiagnosticHandlers { data, llcx }
}
}
impl<'a> Drop for DiagnosticHandlers<'a> {
fn drop(&mut self) {
use std::ptr::null_mut;
unsafe {
llvm::LLVMRustSetInlineAsmDiagnosticHandler(self.llcx, inline_asm_handler, null_mut());
llvm::LLVMContextSetDiagnosticHandler(self.llcx, diagnostic_handler, null_mut());
drop(Box::from_raw(self.data));
}
}
}
unsafe extern "C" fn report_inline_asm<'a, 'b>(cgcx: &'a CodegenContext<LlvmCodegenBackend>,
msg: &'b str,
cookie: c_uint) {
cgcx.diag_emitter.inline_asm_error(cookie as u32, msg.to_owned());
}
unsafe extern "C" fn inline_asm_handler(diag: &SMDiagnostic,
user: *const c_void,
cookie: c_uint) {
if user.is_null() {
return
}
let (cgcx, _) = *(user as *const (&CodegenContext<LlvmCodegenBackend>, &Handler));
let msg = llvm::build_string(|s| llvm::LLVMRustWriteSMDiagnosticToString(diag, s))
.expect("non-UTF8 SMDiagnostic");
report_inline_asm(cgcx, &msg, cookie);
}
unsafe extern "C" fn diagnostic_handler(info: &DiagnosticInfo, user: *mut c_void) {
if user.is_null() {
return
}
let (cgcx, diag_handler) = *(user as *const (&CodegenContext<LlvmCodegenBackend>, &Handler));
match llvm::diagnostic::Diagnostic::unpack(info) {
llvm::diagnostic::InlineAsm(inline) => {
report_inline_asm(cgcx,
&llvm::twine_to_string(inline.message),
inline.cookie);
}
llvm::diagnostic::Optimization(opt) => {
let enabled = match cgcx.remark {
Passes::All => true,
Passes::Some(ref v) => v.iter().any(|s| *s == opt.pass_name),
};
if enabled {
diag_handler.note_without_error(&format!("optimization {} for {} at {}:{}:{}: {}",
opt.kind.describe(),
opt.pass_name,
opt.filename,
opt.line,
opt.column,
opt.message));
}
}
llvm::diagnostic::PGO(diagnostic_ref) |
llvm::diagnostic::Linker(diagnostic_ref) => {
let msg = llvm::build_string(|s| {
llvm::LLVMRustWriteDiagnosticInfoToString(diagnostic_ref, s)
}).expect("non-UTF8 diagnostic");
diag_handler.warn(&msg);
}
llvm::diagnostic::UnknownDiagnostic(..) => {},
}
}
// Unsafe due to LLVM calls.
pub(crate) unsafe fn optimize(cgcx: &CodegenContext<LlvmCodegenBackend>,
diag_handler: &Handler,
module: &ModuleCodegen<ModuleLlvm>,
config: &ModuleConfig)
-> Result<(), FatalError>
{
let llmod = module.module_llvm.llmod();
let llcx = &*module.module_llvm.llcx;
let tm = &*module.module_llvm.tm;
let _handlers = DiagnosticHandlers::new(cgcx, diag_handler, llcx);
let module_name = module.name.clone();
let module_name = Some(&module_name[..]);
if config.emit_no_opt_bc {
let out = cgcx.output_filenames.temp_path_ext("no-opt.bc", module_name);
let out = path_to_c_string(&out);
llvm::LLVMWriteBitcodeToFile(llmod, out.as_ptr());
}
if config.opt_level.is_some() {
// Create the two optimizing pass managers. These mirror what clang
// does, and are by populated by LLVM's default PassManagerBuilder.
// Each manager has a different set of passes, but they also share
// some common passes.
let fpm = llvm::LLVMCreateFunctionPassManagerForModule(llmod);
let mpm = llvm::LLVMCreatePassManager();
{
// If we're verifying or linting, add them to the function pass
// manager.
let addpass = |pass_name: &str| {
let pass_name = SmallCStr::new(pass_name);
let pass = match llvm::LLVMRustFindAndCreatePass(pass_name.as_ptr()) {
Some(pass) => pass,
None => return false,
};
let pass_manager = match llvm::LLVMRustPassKind(pass) {
llvm::PassKind::Function => &*fpm,
llvm::PassKind::Module => &*mpm,
llvm::PassKind::Other => {
diag_handler.err("Encountered LLVM pass kind we can't handle");
return true
},
};
llvm::LLVMRustAddPass(pass_manager, pass);
true
};
if config.verify_llvm_ir { assert!(addpass("verify")); }
// Some options cause LLVM bitcode to be emitted, which uses ThinLTOBuffers, so we need
// to make sure we run LLVM's NameAnonGlobals pass when emitting bitcode; otherwise
// we'll get errors in LLVM.
let using_thin_buffers = config.bitcode_needed();
let mut have_name_anon_globals_pass = false;
if !config.no_prepopulate_passes {
llvm::LLVMRustAddAnalysisPasses(tm, fpm, llmod);
llvm::LLVMRustAddAnalysisPasses(tm, mpm, llmod);
let opt_level = config.opt_level.map(|x| to_llvm_opt_settings(x).0)
.unwrap_or(llvm::CodeGenOptLevel::None);
let prepare_for_thin_lto = cgcx.lto == Lto::Thin || cgcx.lto == Lto::ThinLocal ||
(cgcx.lto != Lto::Fat && cgcx.opts.cg.linker_plugin_lto.enabled());
with_llvm_pmb(llmod, &config, opt_level, prepare_for_thin_lto, &mut |b| {
llvm::LLVMPassManagerBuilderPopulateFunctionPassManager(b, fpm);
llvm::LLVMPassManagerBuilderPopulateModulePassManager(b, mpm);
});
have_name_anon_globals_pass = have_name_anon_globals_pass || prepare_for_thin_lto;
if using_thin_buffers && !prepare_for_thin_lto {
assert!(addpass("name-anon-globals"));
have_name_anon_globals_pass = true;
}
}
for pass in &config.passes {
if !addpass(pass) {
diag_handler.warn(&format!("unknown pass `{}`, ignoring", pass));
}
if pass == "name-anon-globals" {
have_name_anon_globals_pass = true;
}
}
for pass in &cgcx.plugin_passes {
if !addpass(pass) {
diag_handler.err(&format!("a plugin asked for LLVM pass \
`{}` but LLVM does not \
recognize it", pass));
}
if pass == "name-anon-globals" {
have_name_anon_globals_pass = true;
}
}
if using_thin_buffers && !have_name_anon_globals_pass {
// As described above, this will probably cause an error in LLVM
if config.no_prepopulate_passes {
diag_handler.err("The current compilation is going to use thin LTO buffers \
without running LLVM's NameAnonGlobals pass. \
This will likely cause errors in LLVM. Consider adding \
-C passes=name-anon-globals to the compiler command line.");
} else {
bug!("We are using thin LTO buffers without running the NameAnonGlobals pass. \
This will likely cause errors in LLVM and should never happen.");
}
}
}
diag_handler.abort_if_errors();
// Finally, run the actual optimization passes
{
let _timer = cgcx.profile_activity(ProfileCategory::Codegen, "LLVM_function_passes");
time_ext(config.time_passes,
None,
&format!("llvm function passes [{}]", module_name.unwrap()),
|| {
llvm::LLVMRustRunFunctionPassManager(fpm, llmod)
});
}
{
let _timer = cgcx.profile_activity(ProfileCategory::Codegen, "LLVM_module_passes");
time_ext(config.time_passes,
None,
&format!("llvm module passes [{}]", module_name.unwrap()),
|| {
llvm::LLVMRunPassManager(mpm, llmod)
});
}
// Deallocate managers that we're now done with
llvm::LLVMDisposePassManager(fpm);
llvm::LLVMDisposePassManager(mpm);
}
Ok(())
}
pub(crate) unsafe fn codegen(cgcx: &CodegenContext<LlvmCodegenBackend>,
diag_handler: &Handler,
module: ModuleCodegen<ModuleLlvm>,
config: &ModuleConfig)
-> Result<CompiledModule, FatalError>
{
let _timer = cgcx.profile_activity(ProfileCategory::Codegen, "codegen");
{
let llmod = module.module_llvm.llmod();
let llcx = &*module.module_llvm.llcx;
let tm = &*module.module_llvm.tm;
let module_name = module.name.clone();
let module_name = Some(&module_name[..]);
let handlers = DiagnosticHandlers::new(cgcx, diag_handler, llcx);
if cgcx.msvc_imps_needed {
create_msvc_imps(cgcx, llcx, llmod);
}
// A codegen-specific pass manager is used to generate object
// files for an LLVM module.
//
// Apparently each of these pass managers is a one-shot kind of
// thing, so we create a new one for each type of output. The
// pass manager passed to the closure should be ensured to not
// escape the closure itself, and the manager should only be
// used once.
unsafe fn with_codegen<'ll, F, R>(tm: &'ll llvm::TargetMachine,
llmod: &'ll llvm::Module,
no_builtins: bool,
f: F) -> R
where F: FnOnce(&'ll mut PassManager<'ll>) -> R,
{
let cpm = llvm::LLVMCreatePassManager();
llvm::LLVMRustAddAnalysisPasses(tm, cpm, llmod);
llvm::LLVMRustAddLibraryInfo(cpm, llmod, no_builtins);
f(cpm)
}
// If we don't have the integrated assembler, then we need to emit asm
// from LLVM and use `gcc` to create the object file.
let asm_to_obj = config.emit_obj && config.no_integrated_as;
// Change what we write and cleanup based on whether obj files are
// just llvm bitcode. In that case write bitcode, and possibly
// delete the bitcode if it wasn't requested. Don't generate the
// machine code, instead copy the .o file from the .bc
let write_bc = config.emit_bc || config.obj_is_bitcode;
let rm_bc = !config.emit_bc && config.obj_is_bitcode;
let write_obj = config.emit_obj && !config.obj_is_bitcode && !asm_to_obj;
let copy_bc_to_obj = config.emit_obj && config.obj_is_bitcode;
let bc_out = cgcx.output_filenames.temp_path(OutputType::Bitcode, module_name);
let obj_out = cgcx.output_filenames.temp_path(OutputType::Object, module_name);
if write_bc || config.emit_bc_compressed || config.embed_bitcode {
let _timer = cgcx.profile_activity(ProfileCategory::Codegen, "LLVM_make_bitcode");
let thin = ThinBuffer::new(llmod);
let data = thin.data();
if write_bc {
let _timer = cgcx.profile_activity(ProfileCategory::Codegen, "LLVM_emit_bitcode");
if let Err(e) = fs::write(&bc_out, data) {
let msg = format!("failed to write bytecode to {}: {}", bc_out.display(), e);
diag_handler.err(&msg);
}
}
if config.embed_bitcode {
let _timer = cgcx.profile_activity(ProfileCategory::Codegen, "LLVM_embed_bitcode");
embed_bitcode(cgcx, llcx, llmod, Some(data));
}
if config.emit_bc_compressed {
let _timer = cgcx.profile_activity(ProfileCategory::Codegen,
"LLVM_compress_bitcode");
let dst = bc_out.with_extension(RLIB_BYTECODE_EXTENSION);
let data = bytecode::encode(&module.name, data);
if let Err(e) = fs::write(&dst, data) {
let msg = format!("failed to write bytecode to {}: {}", dst.display(), e);
diag_handler.err(&msg);
}
}
} else if config.embed_bitcode_marker {
embed_bitcode(cgcx, llcx, llmod, None);
}
time_ext(config.time_passes, None, &format!("codegen passes [{}]", module_name.unwrap()),
|| -> Result<(), FatalError> {
if config.emit_ir {
let _timer = cgcx.profile_activity(ProfileCategory::Codegen, "LLVM_emit_ir");
let out = cgcx.output_filenames.temp_path(OutputType::LlvmAssembly, module_name);
let out_c = path_to_c_string(&out);
extern "C" fn demangle_callback(input_ptr: *const c_char,
input_len: size_t,
output_ptr: *mut c_char,
output_len: size_t) -> size_t {
let input = unsafe {
slice::from_raw_parts(input_ptr as *const u8, input_len as usize)
};
let input = match str::from_utf8(input) {
Ok(s) => s,
Err(_) => return 0,
};
let output = unsafe {
slice::from_raw_parts_mut(output_ptr as *mut u8, output_len as usize)
};
let mut cursor = io::Cursor::new(output);
let demangled = match rustc_demangle::try_demangle(input) {
Ok(d) => d,
Err(_) => return 0,
};
if let Err(_) = write!(cursor, "{:#}", demangled) {
// Possible only if provided buffer is not big enough
return 0;
}
cursor.position() as size_t
}
with_codegen(tm, llmod, config.no_builtins, |cpm| {
let result =
llvm::LLVMRustPrintModule(cpm, llmod, out_c.as_ptr(), demangle_callback);
llvm::LLVMDisposePassManager(cpm);
result.into_result().map_err(|()| {
let msg = format!("failed to write LLVM IR to {}", out.display());
llvm_err(diag_handler, &msg)
})
})?;
}
if config.emit_asm || asm_to_obj {
let _timer = cgcx.profile_activity(ProfileCategory::Codegen, "LLVM_emit_asm");
let path = cgcx.output_filenames.temp_path(OutputType::Assembly, module_name);
// We can't use the same module for asm and binary output, because that triggers
// various errors like invalid IR or broken binaries, so we might have to clone the
// module to produce the asm output
let llmod = if config.emit_obj {
llvm::LLVMCloneModule(llmod)
} else {
llmod
};
with_codegen(tm, llmod, config.no_builtins, |cpm| {
write_output_file(diag_handler, tm, cpm, llmod, &path,
llvm::FileType::AssemblyFile)
})?;
}
if write_obj {
let _timer = cgcx.profile_activity(ProfileCategory::Codegen, "LLVM_emit_obj");
with_codegen(tm, llmod, config.no_builtins, |cpm| {
write_output_file(diag_handler, tm, cpm, llmod, &obj_out,
llvm::FileType::ObjectFile)
})?;
} else if asm_to_obj {
let _timer = cgcx.profile_activity(ProfileCategory::Codegen, "LLVM_asm_to_obj");
let assembly = cgcx.output_filenames.temp_path(OutputType::Assembly, module_name);
run_assembler(cgcx, diag_handler, &assembly, &obj_out);
if !config.emit_asm && !cgcx.save_temps {
drop(fs::remove_file(&assembly));
}
}
Ok(())
})?;
if copy_bc_to_obj {
debug!("copying bitcode {:?} to obj {:?}", bc_out, obj_out);
if let Err(e) = link_or_copy(&bc_out, &obj_out) {
diag_handler.err(&format!("failed to copy bitcode to object file: {}", e));
}
}
if rm_bc {
debug!("removing_bitcode {:?}", bc_out);
if let Err(e) = fs::remove_file(&bc_out) {
diag_handler.err(&format!("failed to remove bitcode: {}", e));
}
}
drop(handlers);
}
Ok(module.into_compiled_module(config.emit_obj,
config.emit_bc,
config.emit_bc_compressed,
&cgcx.output_filenames))
}
/// Embed the bitcode of an LLVM module in the LLVM module itself.
///
/// This is done primarily for iOS where it appears to be standard to compile C
/// code at least with `-fembed-bitcode` which creates two sections in the
/// executable:
///
/// * __LLVM,__bitcode
/// * __LLVM,__cmdline
///
/// It appears *both* of these sections are necessary to get the linker to
/// recognize what's going on. For us though we just always throw in an empty
/// cmdline section.
///
/// Furthermore debug/O1 builds don't actually embed bitcode but rather just
/// embed an empty section.
///
/// Basically all of this is us attempting to follow in the footsteps of clang
/// on iOS. See #35968 for lots more info.
unsafe fn embed_bitcode(cgcx: &CodegenContext<LlvmCodegenBackend>,
llcx: &llvm::Context,
llmod: &llvm::Module,
bitcode: Option<&[u8]>) {
let llconst = common::bytes_in_context(llcx, bitcode.unwrap_or(&[]));
let llglobal = llvm::LLVMAddGlobal(
llmod,
common::val_ty(llconst),
"rustc.embedded.module\0".as_ptr() as *const _,
);
llvm::LLVMSetInitializer(llglobal, llconst);
let is_apple = cgcx.opts.target_triple.triple().contains("-ios") ||
cgcx.opts.target_triple.triple().contains("-darwin");
let section = if is_apple {
"__LLVM,__bitcode\0"
} else {
".llvmbc\0"
};
llvm::LLVMSetSection(llglobal, section.as_ptr() as *const _);
llvm::LLVMRustSetLinkage(llglobal, llvm::Linkage::PrivateLinkage);
llvm::LLVMSetGlobalConstant(llglobal, llvm::True);
let llconst = common::bytes_in_context(llcx, &[]);
let llglobal = llvm::LLVMAddGlobal(
llmod,
common::val_ty(llconst),
"rustc.embedded.cmdline\0".as_ptr() as *const _,
);
llvm::LLVMSetInitializer(llglobal, llconst);
let section = if is_apple {
"__LLVM,__cmdline\0"
} else {
".llvmcmd\0"
};
llvm::LLVMSetSection(llglobal, section.as_ptr() as *const _);
llvm::LLVMRustSetLinkage(llglobal, llvm::Linkage::PrivateLinkage);
}
pub unsafe fn with_llvm_pmb(llmod: &llvm::Module,
config: &ModuleConfig,
opt_level: llvm::CodeGenOptLevel,
prepare_for_thin_lto: bool,
f: &mut dyn FnMut(&llvm::PassManagerBuilder)) {
use std::ptr;
// Create the PassManagerBuilder for LLVM. We configure it with
// reasonable defaults and prepare it to actually populate the pass
// manager.
let builder = llvm::LLVMPassManagerBuilderCreate();
let opt_size = config.opt_size.map(|x| to_llvm_opt_settings(x).1)
.unwrap_or(llvm::CodeGenOptSizeNone);
let inline_threshold = config.inline_threshold;
let pgo_gen_path = config.pgo_gen.as_ref().map(|s| {
let s = if s.is_empty() { "default_%m.profraw" } else { s };
CString::new(s.as_bytes()).unwrap()
});
let pgo_use_path = if config.pgo_use.is_empty() {
None
} else {
Some(CString::new(config.pgo_use.as_bytes()).unwrap())
};
llvm::LLVMRustConfigurePassManagerBuilder(
builder,
opt_level,
config.merge_functions,
config.vectorize_slp,
config.vectorize_loop,
prepare_for_thin_lto,
pgo_gen_path.as_ref().map_or(ptr::null(), |s| s.as_ptr()),
pgo_use_path.as_ref().map_or(ptr::null(), |s| s.as_ptr()),
);
llvm::LLVMPassManagerBuilderSetSizeLevel(builder, opt_size as u32);
if opt_size != llvm::CodeGenOptSizeNone {
llvm::LLVMPassManagerBuilderSetDisableUnrollLoops(builder, 1);
}
llvm::LLVMRustAddBuilderLibraryInfo(builder, llmod, config.no_builtins);
// Here we match what clang does (kinda). For O0 we only inline
// always-inline functions (but don't add lifetime intrinsics), at O1 we
// inline with lifetime intrinsics, and O2+ we add an inliner with a
// thresholds copied from clang.
match (opt_level, opt_size, inline_threshold) {
(.., Some(t)) => {
llvm::LLVMPassManagerBuilderUseInlinerWithThreshold(builder, t as u32);
}
(llvm::CodeGenOptLevel::Aggressive, ..) => {
llvm::LLVMPassManagerBuilderUseInlinerWithThreshold(builder, 275);
}
(_, llvm::CodeGenOptSizeDefault, _) => {
llvm::LLVMPassManagerBuilderUseInlinerWithThreshold(builder, 75);
}
(_, llvm::CodeGenOptSizeAggressive, _) => {
llvm::LLVMPassManagerBuilderUseInlinerWithThreshold(builder, 25);
}
(llvm::CodeGenOptLevel::None, ..) => {
llvm::LLVMRustAddAlwaysInlinePass(builder, false);
}
(llvm::CodeGenOptLevel::Less, ..) => {
llvm::LLVMRustAddAlwaysInlinePass(builder, true);
}
(llvm::CodeGenOptLevel::Default, ..) => {
llvm::LLVMPassManagerBuilderUseInlinerWithThreshold(builder, 225);
}
(llvm::CodeGenOptLevel::Other, ..) => {
bug!("CodeGenOptLevel::Other selected")
}
}
f(builder);
llvm::LLVMPassManagerBuilderDispose(builder);
}
// Create a `__imp_<symbol> = &symbol` global for every public static `symbol`.
// This is required to satisfy `dllimport` references to static data in .rlibs
// when using MSVC linker. We do this only for data, as linker can fix up
// code references on its own.
// See #26591, #27438
fn create_msvc_imps(
cgcx: &CodegenContext<LlvmCodegenBackend>,
llcx: &llvm::Context,
llmod: &llvm::Module
) {
if !cgcx.msvc_imps_needed {
return
}
// The x86 ABI seems to require that leading underscores are added to symbol
// names, so we need an extra underscore on 32-bit. There's also a leading
// '\x01' here which disables LLVM's symbol mangling (e.g., no extra
// underscores added in front).
let prefix = if cgcx.target_pointer_width == "32" {
"\x01__imp__"
} else {
"\x01__imp_"
};
unsafe {
let i8p_ty = Type::i8p_llcx(llcx);
let globals = base::iter_globals(llmod)
.filter(|&val| {
llvm::LLVMRustGetLinkage(val) == llvm::Linkage::ExternalLinkage &&
llvm::LLVMIsDeclaration(val) == 0
})
.map(move |val| {
let name = CStr::from_ptr(llvm::LLVMGetValueName(val));
let mut imp_name = prefix.as_bytes().to_vec();
imp_name.extend(name.to_bytes());
let imp_name = CString::new(imp_name).unwrap();
(imp_name, val)
})
.collect::<Vec<_>>();
for (imp_name, val) in globals {
let imp = llvm::LLVMAddGlobal(llmod,
i8p_ty,
imp_name.as_ptr() as *const _);
llvm::LLVMSetInitializer(imp, consts::ptrcast(val, i8p_ty));
llvm::LLVMRustSetLinkage(imp, llvm::Linkage::ExternalLinkage);
}
}
}