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use super::link;
use super::write;
use rustc::session::{self, config};
use llvm;
use llvm::archive_ro::ArchiveRO;
use llvm::{ModuleRef, TargetMachineRef, True, False};
use rustc::metadata::cstore;
use rustc::util::common::time;
use libc;
use flate;
use std::ffi::CString;
pub fn run(sess: &session::Session, llmod: ModuleRef,
tm: TargetMachineRef, reachable: &[String]) {
if sess.opts.cg.prefer_dynamic {
sess.err("cannot prefer dynamic linking when performing LTO");
sess.note("only 'staticlib' and 'bin' outputs are supported with LTO");
sess.abort_if_errors();
}
for crate_type in &*sess.crate_types.borrow() {
match *crate_type {
config::CrateTypeExecutable | config::CrateTypeStaticlib => {}
_ => {
sess.fatal("lto can only be run for executables and \
static library outputs");
}
}
}
let crates = sess.cstore.get_used_crates(cstore::RequireStatic);
for (cnum, path) in crates {
let name = sess.cstore.get_crate_data(cnum).name.clone();
let path = match path {
Some(p) => p,
None => {
sess.fatal(&format!("could not find rlib for: `{}`",
name));
}
};
let archive = ArchiveRO::open(&path).expect("wanted an rlib");
let file = path.file_name().unwrap().to_str().unwrap();
let file = &file[3..file.len() - 5];
debug!("reading {}", file);
for i in 0.. {
let bc_encoded = time(sess.time_passes(),
&format!("check for {}.{}.bytecode.deflate", name, i),
(),
|_| {
archive.read(&format!("{}.{}.bytecode.deflate",
file, i))
});
let bc_encoded = match bc_encoded {
Some(data) => data,
None => {
if i == 0 {
sess.fatal(&format!("missing compressed bytecode in {}",
path.display()));
}
break;
},
};
let bc_decoded = if is_versioned_bytecode_format(bc_encoded) {
time(sess.time_passes(), &format!("decode {}.{}.bc", file, i), (), |_| {
let version = extract_bytecode_format_version(bc_encoded);
if version == 1 {
let data_size = extract_compressed_bytecode_size_v1(bc_encoded);
let compressed_data = &bc_encoded[
link::RLIB_BYTECODE_OBJECT_V1_DATA_OFFSET..
(link::RLIB_BYTECODE_OBJECT_V1_DATA_OFFSET + data_size as usize)];
match flate::inflate_bytes(compressed_data) {
Ok(inflated) => inflated,
Err(_) => {
sess.fatal(&format!("failed to decompress bc of `{}`",
name))
}
}
} else {
sess.fatal(&format!("Unsupported bytecode format version {}",
version))
}
})
} else {
time(sess.time_passes(), &format!("decode {}.{}.bc", file, i), (), |_| {
match flate::inflate_bytes(bc_encoded) {
Ok(bc) => bc,
Err(_) => {
sess.fatal(&format!("failed to decompress bc of `{}`",
name))
}
}
})
};
let ptr = bc_decoded.as_ptr();
debug!("linking {}, part {}", name, i);
time(sess.time_passes(),
&format!("ll link {}.{}", name, i),
(),
|()| unsafe {
if !llvm::LLVMRustLinkInExternalBitcode(llmod,
ptr as *const libc::c_char,
bc_decoded.len() as libc::size_t) {
write::llvm_err(sess.diagnostic().handler(),
format!("failed to load bc of `{}`",
&name[..]));
}
});
}
}
let cstrs: Vec<CString> = reachable.iter().map(|s| {
CString::new(s.clone()).unwrap()
}).collect();
let arr: Vec<*const libc::c_char> = cstrs.iter().map(|c| c.as_ptr()).collect();
let ptr = arr.as_ptr();
unsafe {
llvm::LLVMRustRunRestrictionPass(llmod,
ptr as *const *const libc::c_char,
arr.len() as libc::size_t);
}
if sess.no_landing_pads() {
unsafe {
llvm::LLVMRustMarkAllFunctionsNounwind(llmod);
}
}
debug!("running the pass manager");
unsafe {
let pm = llvm::LLVMCreatePassManager();
llvm::LLVMRustAddAnalysisPasses(tm, pm, llmod);
llvm::LLVMRustAddPass(pm, "verify\0".as_ptr() as *const _);
let opt = match sess.opts.optimize {
config::No => 0,
config::Less => 1,
config::Default => 2,
config::Aggressive => 3,
};
let builder = llvm::LLVMPassManagerBuilderCreate();
llvm::LLVMPassManagerBuilderSetOptLevel(builder, opt);
llvm::LLVMPassManagerBuilderPopulateLTOPassManager(builder, pm,
False,
True);
llvm::LLVMPassManagerBuilderDispose(builder);
llvm::LLVMRustAddPass(pm, "verify\0".as_ptr() as *const _);
time(sess.time_passes(), "LTO passes", (), |()|
llvm::LLVMRunPassManager(pm, llmod));
llvm::LLVMDisposePassManager(pm);
}
debug!("lto done");
}
fn is_versioned_bytecode_format(bc: &[u8]) -> bool {
let magic_id_byte_count = link::RLIB_BYTECODE_OBJECT_MAGIC.len();
return bc.len() > magic_id_byte_count &&
&bc[..magic_id_byte_count] == link::RLIB_BYTECODE_OBJECT_MAGIC;
}
fn extract_bytecode_format_version(bc: &[u8]) -> u32 {
let pos = link::RLIB_BYTECODE_OBJECT_VERSION_OFFSET;
let byte_data = &bc[pos..pos + 4];
let data = unsafe { *(byte_data.as_ptr() as *const u32) };
u32::from_le(data)
}
fn extract_compressed_bytecode_size_v1(bc: &[u8]) -> u64 {
let pos = link::RLIB_BYTECODE_OBJECT_V1_DATASIZE_OFFSET;
let byte_data = &bc[pos..pos + 8];
let data = unsafe { *(byte_data.as_ptr() as *const u64) };
u64::from_le(data)
}