Rollup merge of #145484 - Zalathar:archive-builder, r=bjorn3

Remove `LlvmArchiveBuilder` and supporting code/bindings

Switching over to the newer Rust-based `ArArchiveBuilder` happened in #128936, a year ago.

Per the comment in `new_archive_builder`, that seems like enough time to justify removing the older, unused `LlvmArchiveBuilder` implementation and its associated bindings.

Fixes #128955.

Author: Zalathar

compiler/rustc_codegen_llvm/src/back/archive.rs

@@ -1,104 +1,21 @@
 //! A helper class for dealing with static archives
 
-use std::ffi::{CStr, CString, c_char, c_void};
-use std::path::{Path, PathBuf};
-use std::{io, mem, ptr, str};
+use std::ffi::{CStr, c_char, c_void};
+use std::io;
 
 use rustc_codegen_ssa::back::archive::{
-    ArArchiveBuilder, ArchiveBuildFailure, ArchiveBuilder, ArchiveBuilderBuilder,
-    DEFAULT_OBJECT_READER, ObjectReader, UnknownArchiveKind, try_extract_macho_fat_archive,
+    ArArchiveBuilder, ArchiveBuilder, ArchiveBuilderBuilder, DEFAULT_OBJECT_READER, ObjectReader,
 };
 use rustc_session::Session;
 
-use crate::llvm::archive_ro::{ArchiveRO, Child};
-use crate::llvm::{self, ArchiveKind, last_error};
-
-/// 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,
-    }
-}
-
-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(error) => {
-                self.sess.dcx().emit_fatal(ArchiveBuildFailure { path: output.to_owned(), error })
-            }
-        }
-    }
-}
+use crate::llvm;
 
 pub(crate) struct LlvmArchiveBuilderBuilder;
 
 impl ArchiveBuilderBuilder for LlvmArchiveBuilderBuilder {
     fn new_archive_builder<'a>(&self, sess: &'a Session) -> Box<dyn ArchiveBuilder + 'a> {
-        // Keeping LlvmArchiveBuilder around in case of a regression caused by using
-        // ArArchiveBuilder.
-        // FIXME(#128955) remove a couple of months after #128936 gets merged in case
-        // no regression is found.
-        if false {
-            Box::new(LlvmArchiveBuilder { sess, additions: Vec::new() })
-        } else {
-            Box::new(ArArchiveBuilder::new(sess, &LLVM_OBJECT_READER))
-        }
+        // Use the `object` crate to build archives, with a little bit of help from LLVM.
+        Box::new(ArArchiveBuilder::new(sess, &LLVM_OBJECT_READER))
     }
 }
 
@@ -178,91 +95,3 @@ fn llvm_is_64_bit_object_file(buf: &[u8]) -> bool {
 fn llvm_is_ec_object_file(buf: &[u8]) -> bool {
     unsafe { llvm::LLVMRustIsECObject(buf.as_ptr(), buf.len()) }
 }
-
-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);
-        // Values in the `members` list below will contain pointers to the strings allocated here.
-        // So they need to get dropped after all elements of `members` get freed.
-        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 msg = last_error().unwrap_or_else(|| "failed to write archive".into());
-                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}"))
-}

compiler/rustc_codegen_llvm/src/llvm/archive_ro.rs

@@ -616,17 +616,6 @@ pub(crate) enum DiagnosticLevel {
     Remark,
 }
 
-/// LLVMRustArchiveKind
-#[derive(Copy, Clone)]
-#[repr(C)]
-pub(crate) enum ArchiveKind {
-    K_GNU,
-    K_BSD,
-    K_DARWIN,
-    K_COFF,
-    K_AIXBIG,
-}
-
 unsafe extern "C" {
     // LLVMRustThinLTOData
     pub(crate) type ThinLTOData;
@@ -775,19 +764,12 @@ pub(crate) struct Builder<'a>(InvariantOpaque<'a>);
 pub(crate) struct PassManager<'a>(InvariantOpaque<'a>);
 unsafe extern "C" {
     pub type TargetMachine;
-    pub(crate) type Archive;
 }
-#[repr(C)]
-pub(crate) struct ArchiveIterator<'a>(InvariantOpaque<'a>);
-#[repr(C)]
-pub(crate) struct ArchiveChild<'a>(InvariantOpaque<'a>);
 unsafe extern "C" {
     pub(crate) type Twine;
     pub(crate) type DiagnosticInfo;
     pub(crate) type SMDiagnostic;
 }
-#[repr(C)]
-pub(crate) struct RustArchiveMember<'a>(InvariantOpaque<'a>);
 /// Opaque pointee of `LLVMOperandBundleRef`.
 #[repr(C)]
 pub(crate) struct OperandBundle<'a>(InvariantOpaque<'a>);
@@ -2510,19 +2492,6 @@ unsafe extern "C" {
     pub(crate) fn LLVMRustSetNormalizedTarget(M: &Module, triple: *const c_char);
     pub(crate) fn LLVMRustRunRestrictionPass(M: &Module, syms: *const *const c_char, len: size_t);
 
-    pub(crate) fn LLVMRustOpenArchive(path: *const c_char) -> Option<&'static mut Archive>;
-    pub(crate) fn LLVMRustArchiveIteratorNew(AR: &Archive) -> &mut ArchiveIterator<'_>;
-    pub(crate) fn LLVMRustArchiveIteratorNext<'a>(
-        AIR: &ArchiveIterator<'a>,
-    ) -> Option<&'a mut ArchiveChild<'a>>;
-    pub(crate) fn LLVMRustArchiveChildName(
-        ACR: &ArchiveChild<'_>,
-        size: &mut size_t,
-    ) -> *const c_char;
-    pub(crate) fn LLVMRustArchiveChildFree<'a>(ACR: &'a mut ArchiveChild<'a>);
-    pub(crate) fn LLVMRustArchiveIteratorFree<'a>(AIR: &'a mut ArchiveIterator<'a>);
-    pub(crate) fn LLVMRustDestroyArchive(AR: &'static mut Archive);
-
     pub(crate) fn LLVMRustWriteTwineToString(T: &Twine, s: &RustString);
 
     pub(crate) fn LLVMRustUnpackOptimizationDiagnostic<'a>(
@@ -2560,21 +2529,6 @@ unsafe extern "C" {
         num_ranges: &mut usize,
     ) -> bool;
 
-    pub(crate) fn LLVMRustWriteArchive(
-        Dst: *const c_char,
-        NumMembers: size_t,
-        Members: *const &RustArchiveMember<'_>,
-        WriteSymbtab: bool,
-        Kind: ArchiveKind,
-        isEC: bool,
-    ) -> LLVMRustResult;
-    pub(crate) fn LLVMRustArchiveMemberNew<'a>(
-        Filename: *const c_char,
-        Name: *const c_char,
-        Child: Option<&ArchiveChild<'a>>,
-    ) -> &'a mut RustArchiveMember<'a>;
-    pub(crate) fn LLVMRustArchiveMemberFree<'a>(Member: &'a mut RustArchiveMember<'a>);
-
     pub(crate) fn LLVMRustSetDataLayoutFromTargetMachine<'a>(M: &'a Module, TM: &'a TargetMachine);
 
     pub(crate) fn LLVMRustPositionBuilderPastAllocas<'a>(B: &Builder<'a>, Fn: &'a Value);