diff options
Diffstat (limited to 'compiler/rustc_codegen_llvm/src/back/archive.rs')
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/back/archive.rs | 477 |
1 files changed, 477 insertions, 0 deletions
diff --git a/compiler/rustc_codegen_llvm/src/back/archive.rs b/compiler/rustc_codegen_llvm/src/back/archive.rs new file mode 100644 index 00000000000..d4a3e39cef7 --- /dev/null +++ b/compiler/rustc_codegen_llvm/src/back/archive.rs @@ -0,0 +1,477 @@ +//! A helper class for dealing with static archives + +use std::env; +use std::ffi::{c_char, c_void, CStr, CString, OsString}; +use std::io; +use std::mem; +use std::path::{Path, PathBuf}; +use std::ptr; +use std::str; + +use crate::common; +use crate::errors::{ + DlltoolFailImportLibrary, ErrorCallingDllTool, ErrorCreatingImportLibrary, ErrorWritingDEFFile, +}; +use crate::llvm::archive_ro::{ArchiveRO, Child}; +use crate::llvm::{self, ArchiveKind, LLVMMachineType, LLVMRustCOFFShortExport}; +use rustc_codegen_ssa::back::archive::{ + get_native_object_symbols, try_extract_macho_fat_archive, ArArchiveBuilder, + ArchiveBuildFailure, ArchiveBuilder, ArchiveBuilderBuilder, UnknownArchiveKind, +}; + +use rustc_session::cstore::DllImport; +use rustc_session::Session; + +/// Helper for adding many files to an archive. +#[must_use = "must call build() to finish building the archive"] +pub(crate) struct LlvmArchiveBuilder<'a> { + sess: &'a Session, + additions: Vec<Addition>, +} + +enum Addition { + File { path: PathBuf, name_in_archive: String }, + Archive { path: PathBuf, archive: ArchiveRO, skip: Box<dyn FnMut(&str) -> bool> }, +} + +impl Addition { + fn path(&self) -> &Path { + match self { + Addition::File { path, .. } | Addition::Archive { path, .. } => path, + } + } +} + +fn is_relevant_child(c: &Child<'_>) -> bool { + match c.name() { + Some(name) => !name.contains("SYMDEF"), + None => false, + } +} + +/// Map machine type strings to values of LLVM's MachineTypes enum. +fn llvm_machine_type(cpu: &str) -> LLVMMachineType { + match cpu { + "x86_64" => LLVMMachineType::AMD64, + "x86" => LLVMMachineType::I386, + "aarch64" => LLVMMachineType::ARM64, + "arm64ec" => LLVMMachineType::ARM64EC, + "arm" => LLVMMachineType::ARM, + _ => panic!("unsupported cpu type {cpu}"), + } +} + +impl<'a> ArchiveBuilder for LlvmArchiveBuilder<'a> { + fn add_archive( + &mut self, + archive: &Path, + skip: Box<dyn FnMut(&str) -> bool + 'static>, + ) -> io::Result<()> { + let mut archive = archive.to_path_buf(); + if self.sess.target.llvm_target.contains("-apple-macosx") { + if let Some(new_archive) = try_extract_macho_fat_archive(self.sess, &archive)? { + archive = new_archive + } + } + let archive_ro = match ArchiveRO::open(&archive) { + Ok(ar) => ar, + Err(e) => return Err(io::Error::new(io::ErrorKind::Other, e)), + }; + if self.additions.iter().any(|ar| ar.path() == archive) { + return Ok(()); + } + self.additions.push(Addition::Archive { + path: archive, + archive: archive_ro, + skip: Box::new(skip), + }); + Ok(()) + } + + /// Adds an arbitrary file to this archive + fn add_file(&mut self, file: &Path) { + let name = file.file_name().unwrap().to_str().unwrap(); + self.additions + .push(Addition::File { path: file.to_path_buf(), name_in_archive: name.to_owned() }); + } + + /// Combine the provided files, rlibs, and native libraries into a single + /// `Archive`. + fn build(mut self: Box<Self>, output: &Path) -> bool { + match self.build_with_llvm(output) { + Ok(any_members) => any_members, + Err(e) => self.sess.dcx().emit_fatal(ArchiveBuildFailure { error: e }), + } + } +} + +pub struct LlvmArchiveBuilderBuilder; + +impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder { + fn new_archive_builder<'a>(&self, sess: &'a Session) -> Box<dyn ArchiveBuilder + 'a> { + // FIXME use ArArchiveBuilder on most targets again once reading thin archives is + // implemented + if true { + Box::new(LlvmArchiveBuilder { sess, additions: Vec::new() }) + } else { + Box::new(ArArchiveBuilder::new(sess, get_llvm_object_symbols)) + } + } + + fn create_dll_import_lib( + &self, + sess: &Session, + lib_name: &str, + dll_imports: &[DllImport], + tmpdir: &Path, + is_direct_dependency: bool, + ) -> PathBuf { + let name_suffix = if is_direct_dependency { "_imports" } else { "_imports_indirect" }; + let output_path = { + let mut output_path: PathBuf = tmpdir.to_path_buf(); + output_path.push(format!("{lib_name}{name_suffix}")); + output_path.with_extension("lib") + }; + + let target = &sess.target; + let mingw_gnu_toolchain = common::is_mingw_gnu_toolchain(target); + + let import_name_and_ordinal_vector: Vec<(String, Option<u16>)> = dll_imports + .iter() + .map(|import: &DllImport| { + if sess.target.arch == "x86" { + ( + common::i686_decorated_name(import, mingw_gnu_toolchain, false), + import.ordinal(), + ) + } else { + (import.name.to_string(), import.ordinal()) + } + }) + .collect(); + + if mingw_gnu_toolchain { + // The binutils linker used on -windows-gnu targets cannot read the import + // libraries generated by LLVM: in our attempts, the linker produced an .EXE + // that loaded but crashed with an AV upon calling one of the imported + // functions. Therefore, use binutils to create the import library instead, + // by writing a .DEF file to the temp dir and calling binutils's dlltool. + let def_file_path = + tmpdir.join(format!("{lib_name}{name_suffix}")).with_extension("def"); + + let def_file_content = format!( + "EXPORTS\n{}", + import_name_and_ordinal_vector + .into_iter() + .map(|(name, ordinal)| { + match ordinal { + Some(n) => format!("{name} @{n} NONAME"), + None => name, + } + }) + .collect::<Vec<String>>() + .join("\n") + ); + + match std::fs::write(&def_file_path, def_file_content) { + Ok(_) => {} + Err(e) => { + sess.dcx().emit_fatal(ErrorWritingDEFFile { error: e }); + } + }; + + // --no-leading-underscore: For the `import_name_type` feature to work, we need to be + // able to control the *exact* spelling of each of the symbols that are being imported: + // hence we don't want `dlltool` adding leading underscores automatically. + let dlltool = find_binutils_dlltool(sess); + let temp_prefix = { + let mut path = PathBuf::from(&output_path); + path.pop(); + path.push(lib_name); + path + }; + // dlltool target architecture args from: + // https://github.com/llvm/llvm-project-release-prs/blob/llvmorg-15.0.6/llvm/lib/ToolDrivers/llvm-dlltool/DlltoolDriver.cpp#L69 + let (dlltool_target_arch, dlltool_target_bitness) = match sess.target.arch.as_ref() { + "x86_64" => ("i386:x86-64", "--64"), + "x86" => ("i386", "--32"), + "aarch64" => ("arm64", "--64"), + "arm" => ("arm", "--32"), + _ => panic!("unsupported arch {}", sess.target.arch), + }; + let mut dlltool_cmd = std::process::Command::new(&dlltool); + dlltool_cmd.args([ + "-d", + def_file_path.to_str().unwrap(), + "-D", + lib_name, + "-l", + output_path.to_str().unwrap(), + "-m", + dlltool_target_arch, + "-f", + dlltool_target_bitness, + "--no-leading-underscore", + "--temp-prefix", + temp_prefix.to_str().unwrap(), + ]); + + match dlltool_cmd.output() { + Err(e) => { + sess.dcx().emit_fatal(ErrorCallingDllTool { + dlltool_path: dlltool.to_string_lossy(), + error: e, + }); + } + // dlltool returns '0' on failure, so check for error output instead. + Ok(output) if !output.stderr.is_empty() => { + sess.dcx().emit_fatal(DlltoolFailImportLibrary { + dlltool_path: dlltool.to_string_lossy(), + dlltool_args: dlltool_cmd + .get_args() + .map(|arg| arg.to_string_lossy()) + .collect::<Vec<_>>() + .join(" "), + stdout: String::from_utf8_lossy(&output.stdout), + stderr: String::from_utf8_lossy(&output.stderr), + }) + } + _ => {} + } + } else { + // we've checked for \0 characters in the library name already + let dll_name_z = CString::new(lib_name).unwrap(); + + let output_path_z = rustc_fs_util::path_to_c_string(&output_path); + + trace!("invoking LLVMRustWriteImportLibrary"); + trace!(" dll_name {:#?}", dll_name_z); + trace!(" output_path {}", output_path.display()); + trace!( + " import names: {}", + dll_imports + .iter() + .map(|import| import.name.to_string()) + .collect::<Vec<_>>() + .join(", "), + ); + + // All import names are Rust identifiers and therefore cannot contain \0 characters. + // FIXME: when support for #[link_name] is implemented, ensure that the import names + // still don't contain any \0 characters. Also need to check that the names don't + // contain substrings like " @" or "NONAME" that are keywords or otherwise reserved + // in definition files. + let cstring_import_name_and_ordinal_vector: Vec<(CString, Option<u16>)> = + import_name_and_ordinal_vector + .into_iter() + .map(|(name, ordinal)| (CString::new(name).unwrap(), ordinal)) + .collect(); + + let ffi_exports: Vec<LLVMRustCOFFShortExport> = cstring_import_name_and_ordinal_vector + .iter() + .map(|(name_z, ordinal)| LLVMRustCOFFShortExport::new(name_z.as_ptr(), *ordinal)) + .collect(); + let result = unsafe { + crate::llvm::LLVMRustWriteImportLibrary( + dll_name_z.as_ptr(), + output_path_z.as_ptr(), + ffi_exports.as_ptr(), + ffi_exports.len(), + llvm_machine_type(&sess.target.arch) as u16, + !sess.target.is_like_msvc, + ) + }; + + if result == crate::llvm::LLVMRustResult::Failure { + sess.dcx().emit_fatal(ErrorCreatingImportLibrary { + lib_name, + error: llvm::last_error().unwrap_or("unknown LLVM error".to_string()), + }); + } + }; + + output_path + } +} + +// The object crate doesn't know how to get symbols for LLVM bitcode and COFF bigobj files. +// As such we need to use LLVM for them. +#[deny(unsafe_op_in_unsafe_fn)] +fn get_llvm_object_symbols( + buf: &[u8], + f: &mut dyn FnMut(&[u8]) -> io::Result<()>, +) -> io::Result<bool> { + let is_bitcode = unsafe { llvm::LLVMRustIsBitcode(buf.as_ptr(), buf.len()) }; + + // COFF bigobj file, msvc LTO file or import library. See + // https://github.com/llvm/llvm-project/blob/453f27bc9/llvm/lib/BinaryFormat/Magic.cpp#L38-L51 + let is_unsupported_windows_obj_file = buf.get(0..4) == Some(b"\0\0\xFF\xFF"); + + if is_bitcode || is_unsupported_windows_obj_file { + let mut state = Box::new(f); + + let err = unsafe { + llvm::LLVMRustGetSymbols( + buf.as_ptr(), + buf.len(), + std::ptr::addr_of_mut!(*state) as *mut c_void, + callback, + error_callback, + ) + }; + + if err.is_null() { + return Ok(true); + } else { + return Err(unsafe { *Box::from_raw(err as *mut io::Error) }); + } + + unsafe extern "C" fn callback( + state: *mut c_void, + symbol_name: *const c_char, + ) -> *mut c_void { + let f = unsafe { &mut *(state as *mut &mut dyn FnMut(&[u8]) -> io::Result<()>) }; + match f(unsafe { CStr::from_ptr(symbol_name) }.to_bytes()) { + Ok(()) => std::ptr::null_mut(), + Err(err) => Box::into_raw(Box::new(err)) as *mut c_void, + } + } + + unsafe extern "C" fn error_callback(error: *const c_char) -> *mut c_void { + let error = unsafe { CStr::from_ptr(error) }; + Box::into_raw(Box::new(io::Error::new( + io::ErrorKind::Other, + format!("LLVM error: {}", error.to_string_lossy()), + ))) as *mut c_void + } + } else { + get_native_object_symbols(buf, f) + } +} + +impl<'a> LlvmArchiveBuilder<'a> { + fn build_with_llvm(&mut self, output: &Path) -> io::Result<bool> { + let kind = &*self.sess.target.archive_format; + let kind = kind + .parse::<ArchiveKind>() + .map_err(|_| kind) + .unwrap_or_else(|kind| self.sess.dcx().emit_fatal(UnknownArchiveKind { kind })); + + let mut additions = mem::take(&mut self.additions); + let mut strings = Vec::new(); + let mut members = Vec::new(); + + let dst = CString::new(output.to_str().unwrap())?; + + unsafe { + for addition in &mut additions { + match addition { + Addition::File { path, name_in_archive } => { + let path = CString::new(path.to_str().unwrap())?; + let name = CString::new(name_in_archive.as_bytes())?; + members.push(llvm::LLVMRustArchiveMemberNew( + path.as_ptr(), + name.as_ptr(), + None, + )); + strings.push(path); + strings.push(name); + } + Addition::Archive { archive, skip, .. } => { + for child in archive.iter() { + let child = child.map_err(string_to_io_error)?; + if !is_relevant_child(&child) { + continue; + } + let child_name = child.name().unwrap(); + if skip(child_name) { + continue; + } + + // It appears that LLVM's archive writer is a little + // buggy if the name we pass down isn't just the + // filename component, so chop that off here and + // pass it in. + // + // See LLVM bug 25877 for more info. + let child_name = + Path::new(child_name).file_name().unwrap().to_str().unwrap(); + let name = CString::new(child_name)?; + let m = llvm::LLVMRustArchiveMemberNew( + ptr::null(), + name.as_ptr(), + Some(child.raw), + ); + members.push(m); + strings.push(name); + } + } + } + } + + let r = llvm::LLVMRustWriteArchive( + dst.as_ptr(), + members.len() as libc::size_t, + members.as_ptr() as *const &_, + true, + kind, + self.sess.target.arch == "arm64ec", + ); + let ret = if r.into_result().is_err() { + let err = llvm::LLVMRustGetLastError(); + let msg = if err.is_null() { + "failed to write archive".into() + } else { + String::from_utf8_lossy(CStr::from_ptr(err).to_bytes()) + }; + Err(io::Error::new(io::ErrorKind::Other, msg)) + } else { + Ok(!members.is_empty()) + }; + for member in members { + llvm::LLVMRustArchiveMemberFree(member); + } + ret + } + } +} + +fn string_to_io_error(s: String) -> io::Error { + io::Error::new(io::ErrorKind::Other, format!("bad archive: {s}")) +} + +fn find_binutils_dlltool(sess: &Session) -> OsString { + assert!(sess.target.options.is_like_windows && !sess.target.options.is_like_msvc); + if let Some(dlltool_path) = &sess.opts.cg.dlltool { + return dlltool_path.clone().into_os_string(); + } + + let tool_name: OsString = if sess.host.options.is_like_windows { + // If we're compiling on Windows, always use "dlltool.exe". + "dlltool.exe" + } else { + // On other platforms, use the architecture-specific name. + match sess.target.arch.as_ref() { + "x86_64" => "x86_64-w64-mingw32-dlltool", + "x86" => "i686-w64-mingw32-dlltool", + "aarch64" => "aarch64-w64-mingw32-dlltool", + + // For non-standard architectures (e.g., aarch32) fallback to "dlltool". + _ => "dlltool", + } + } + .into(); + + // NOTE: it's not clear how useful it is to explicitly search PATH. + for dir in env::split_paths(&env::var_os("PATH").unwrap_or_default()) { + let full_path = dir.join(&tool_name); + if full_path.is_file() { + return full_path.into_os_string(); + } + } + + // The user didn't specify the location of the dlltool binary, and we weren't able + // to find the appropriate one on the PATH. Just return the name of the tool + // and let the invocation fail with a hopefully useful error message. + tool_name +} |