diff options
| -rw-r--r-- | Cargo.lock | 1 | ||||
| -rw-r--r-- | compiler/rustc_codegen_cranelift/src/lib.rs | 2 | ||||
| -rw-r--r-- | compiler/rustc_codegen_cranelift/src/metadata.rs | 66 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/base.rs | 18 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/lib.rs | 3 | ||||
| -rw-r--r-- | compiler/rustc_codegen_llvm/src/metadata.rs | 112 | ||||
| -rw-r--r-- | compiler/rustc_codegen_ssa/Cargo.toml | 5 | ||||
| -rw-r--r-- | compiler/rustc_codegen_ssa/src/back/metadata.rs | 71 | ||||
| -rw-r--r-- | compiler/rustc_codegen_ssa/src/back/mod.rs | 1 | ||||
| -rw-r--r-- | src/test/run-make-fulldeps/hotplug_codegen_backend/the_backend.rs | 14 |
10 files changed, 98 insertions, 195 deletions
diff --git a/Cargo.lock b/Cargo.lock index 3d675e10bf2..e92b7287f3e 100644 --- a/Cargo.lock +++ b/Cargo.lock @@ -3695,6 +3695,7 @@ dependencies = [ "itertools 0.9.0", "jobserver", "libc", + "object", "pathdiff", "rustc_apfloat", "rustc_ast", diff --git a/compiler/rustc_codegen_cranelift/src/lib.rs b/compiler/rustc_codegen_cranelift/src/lib.rs index 4271f695f91..ff6e1856059 100644 --- a/compiler/rustc_codegen_cranelift/src/lib.rs +++ b/compiler/rustc_codegen_cranelift/src/lib.rs @@ -165,7 +165,7 @@ impl CodegenBackend for CraneliftCodegenBackend { } fn metadata_loader(&self) -> Box<dyn MetadataLoader + Sync> { - Box::new(crate::metadata::CraneliftMetadataLoader) + Box::new(rustc_codegen_ssa::back::metadata::DefaultMetadataLoader) } fn provide(&self, _providers: &mut Providers) {} diff --git a/compiler/rustc_codegen_cranelift/src/metadata.rs b/compiler/rustc_codegen_cranelift/src/metadata.rs index 882232fde09..ab238244d68 100644 --- a/compiler/rustc_codegen_cranelift/src/metadata.rs +++ b/compiler/rustc_codegen_cranelift/src/metadata.rs @@ -1,73 +1,9 @@ -//! Reading and writing of the rustc metadata for rlibs and dylibs +//! Writing of the rustc metadata for dylibs -use std::fs::File; -use std::path::Path; - -use rustc_codegen_ssa::METADATA_FILENAME; -use rustc_data_structures::memmap::Mmap; -use rustc_data_structures::owning_ref::OwningRef; -use rustc_data_structures::rustc_erase_owner; -use rustc_data_structures::sync::MetadataRef; -use rustc_middle::middle::cstore::MetadataLoader; use rustc_middle::ty::TyCtxt; -use rustc_target::spec::Target; use crate::backend::WriteMetadata; -/// The metadata loader used by cg_clif. -/// -/// The metadata is stored in the same format as cg_llvm. -/// -/// # Metadata location -/// -/// <dl> -/// <dt>rlib</dt> -/// <dd>The metadata can be found in the `lib.rmeta` file inside of the ar archive.</dd> -/// <dt>dylib</dt> -/// <dd>The metadata can be found in the `.rustc` section of the shared library.</dd> -/// </dl> -pub(crate) struct CraneliftMetadataLoader; - -fn load_metadata_with( - path: &Path, - f: impl for<'a> FnOnce(&'a [u8]) -> Result<&'a [u8], String>, -) -> Result<MetadataRef, String> { - let file = File::open(path).map_err(|e| format!("{:?}", e))?; - let data = unsafe { Mmap::map(file) }.map_err(|e| format!("{:?}", e))?; - let metadata = OwningRef::new(data).try_map(f)?; - return Ok(rustc_erase_owner!(metadata.map_owner_box())); -} - -impl MetadataLoader for CraneliftMetadataLoader { - fn get_rlib_metadata(&self, _target: &Target, path: &Path) -> Result<MetadataRef, String> { - load_metadata_with(path, |data| { - let archive = object::read::archive::ArchiveFile::parse(&*data) - .map_err(|e| format!("{:?}", e))?; - - for entry_result in archive.members() { - let entry = entry_result.map_err(|e| format!("{:?}", e))?; - if entry.name() == METADATA_FILENAME.as_bytes() { - return Ok(entry.data()); - } - } - - Err("couldn't find metadata entry".to_string()) - }) - } - - fn get_dylib_metadata(&self, _target: &Target, path: &Path) -> Result<MetadataRef, String> { - use object::{Object, ObjectSection}; - - load_metadata_with(path, |data| { - let file = object::File::parse(&data).map_err(|e| format!("parse: {:?}", e))?; - file.section_by_name(".rustc") - .ok_or("no .rustc section")? - .data() - .map_err(|e| format!("failed to read .rustc section: {:?}", e)) - }) - } -} - // Adapted from https://github.com/rust-lang/rust/blob/da573206f87b5510de4b0ee1a9c044127e409bd3/src/librustc_codegen_llvm/base.rs#L47-L112 pub(crate) fn write_metadata<O: WriteMetadata>(tcx: TyCtxt<'_>, object: &mut O) { use snap::write::FrameEncoder; diff --git a/compiler/rustc_codegen_llvm/src/base.rs b/compiler/rustc_codegen_llvm/src/base.rs index 6f6c649bb0b..893c909b204 100644 --- a/compiler/rustc_codegen_llvm/src/base.rs +++ b/compiler/rustc_codegen_llvm/src/base.rs @@ -18,7 +18,6 @@ use crate::builder::Builder; use crate::common; use crate::context::CodegenCx; use crate::llvm; -use crate::metadata; use crate::value::Value; use rustc_codegen_ssa::base::maybe_create_entry_wrapper; @@ -47,6 +46,22 @@ pub fn write_compressed_metadata<'tcx>( use snap::write::FrameEncoder; use std::io::Write; + // Historical note: + // + // When using link.exe it was seen that the section name `.note.rustc` + // was getting shortened to `.note.ru`, and according to the PE and COFF + // specification: + // + // > Executable images do not use a string table and do not support + // > section names longer than 8 characters + // + // https://docs.microsoft.com/en-us/windows/win32/debug/pe-format + // + // As a result, we choose a slightly shorter name! As to why + // `.note.rustc` works on MinGW, see + // https://github.com/llvm/llvm-project/blob/llvmorg-12.0.0/lld/COFF/Writer.cpp#L1190-L1197 + let section_name = if tcx.sess.target.is_like_osx { "__DATA,.rustc" } else { ".rustc" }; + let (metadata_llcx, metadata_llmod) = (&*llvm_module.llcx, llvm_module.llmod()); let mut compressed = tcx.metadata_encoding_version(); FrameEncoder::new(&mut compressed).write_all(&metadata.raw_data).unwrap(); @@ -59,7 +74,6 @@ pub fn write_compressed_metadata<'tcx>( unsafe { llvm::LLVMAddGlobal(metadata_llmod, common::val_ty(llconst), buf.as_ptr()) }; unsafe { llvm::LLVMSetInitializer(llglobal, llconst); - let section_name = metadata::metadata_section_name(&tcx.sess.target); let name = SmallCStr::new(section_name); llvm::LLVMSetSection(llglobal, name.as_ptr()); diff --git a/compiler/rustc_codegen_llvm/src/lib.rs b/compiler/rustc_codegen_llvm/src/lib.rs index 91062926788..329458773ff 100644 --- a/compiler/rustc_codegen_llvm/src/lib.rs +++ b/compiler/rustc_codegen_llvm/src/lib.rs @@ -69,7 +69,6 @@ pub mod llvm { } mod llvm_util; -mod metadata; mod mono_item; mod type_; mod type_of; @@ -251,7 +250,7 @@ impl CodegenBackend for LlvmCodegenBackend { } fn metadata_loader(&self) -> Box<MetadataLoaderDyn> { - Box::new(metadata::LlvmMetadataLoader) + Box::new(rustc_codegen_ssa::back::metadata::DefaultMetadataLoader) } fn provide(&self, _providers: &mut ty::query::Providers) {} diff --git a/compiler/rustc_codegen_llvm/src/metadata.rs b/compiler/rustc_codegen_llvm/src/metadata.rs deleted file mode 100644 index decc1e1f700..00000000000 --- a/compiler/rustc_codegen_llvm/src/metadata.rs +++ /dev/null @@ -1,112 +0,0 @@ -use crate::llvm; -use crate::llvm::archive_ro::ArchiveRO; -use crate::llvm::{mk_section_iter, False, ObjectFile}; -use rustc_middle::middle::cstore::MetadataLoader; -use rustc_target::spec::Target; - -use rustc_codegen_ssa::METADATA_FILENAME; -use rustc_data_structures::owning_ref::OwningRef; -use rustc_data_structures::rustc_erase_owner; -use tracing::debug; - -use rustc_fs_util::path_to_c_string; -use std::path::Path; -use std::slice; - -pub use rustc_data_structures::sync::MetadataRef; - -pub struct LlvmMetadataLoader; - -impl MetadataLoader for LlvmMetadataLoader { - fn get_rlib_metadata(&self, _: &Target, filename: &Path) -> Result<MetadataRef, String> { - // Use ArchiveRO for speed here, it's backed by LLVM and uses mmap - // internally to read the file. We also avoid even using a memcpy by - // just keeping the archive along while the metadata is in use. - let archive = - ArchiveRO::open(filename).map(|ar| OwningRef::new(Box::new(ar))).map_err(|e| { - debug!("llvm didn't like `{}`: {}", filename.display(), e); - format!("failed to read rlib metadata in '{}': {}", filename.display(), e) - })?; - let buf: OwningRef<_, [u8]> = archive.try_map(|ar| { - ar.iter() - .filter_map(|s| s.ok()) - .find(|sect| sect.name() == Some(METADATA_FILENAME)) - .map(|s| s.data()) - .ok_or_else(|| { - debug!("didn't find '{}' in the archive", METADATA_FILENAME); - format!("failed to read rlib metadata: '{}'", filename.display()) - }) - })?; - Ok(rustc_erase_owner!(buf)) - } - - fn get_dylib_metadata(&self, target: &Target, filename: &Path) -> Result<MetadataRef, String> { - unsafe { - let buf = path_to_c_string(filename); - let mb = llvm::LLVMRustCreateMemoryBufferWithContentsOfFile(buf.as_ptr()) - .ok_or_else(|| format!("error reading library: '{}'", filename.display()))?; - let of = - ObjectFile::new(mb).map(|of| OwningRef::new(Box::new(of))).ok_or_else(|| { - format!("provided path not an object file: '{}'", filename.display()) - })?; - let buf = of.try_map(|of| search_meta_section(of, target, filename))?; - Ok(rustc_erase_owner!(buf)) - } - } -} - -fn search_meta_section<'a>( - of: &'a ObjectFile, - target: &Target, - filename: &Path, -) -> Result<&'a [u8], String> { - unsafe { - let si = mk_section_iter(of.llof); - while llvm::LLVMIsSectionIteratorAtEnd(of.llof, si.llsi) == False { - let mut name_buf = None; - let name_len = llvm::LLVMRustGetSectionName(si.llsi, &mut name_buf); - let name = name_buf.map_or_else( - String::new, // We got a null ptr, ignore `name_len`. - |buf| { - String::from_utf8( - slice::from_raw_parts(buf.as_ptr() as *const u8, name_len as usize) - .to_vec(), - ) - .unwrap() - }, - ); - debug!("get_metadata_section: name {}", name); - if read_metadata_section_name(target) == name { - let cbuf = llvm::LLVMGetSectionContents(si.llsi); - let csz = llvm::LLVMGetSectionSize(si.llsi) as usize; - // The buffer is valid while the object file is around - let buf: &'a [u8] = slice::from_raw_parts(cbuf as *const u8, csz); - return Ok(buf); - } - llvm::LLVMMoveToNextSection(si.llsi); - } - } - Err(format!("metadata not found: '{}'", filename.display())) -} - -pub fn metadata_section_name(target: &Target) -> &'static str { - // Historical note: - // - // When using link.exe it was seen that the section name `.note.rustc` - // was getting shortened to `.note.ru`, and according to the PE and COFF - // specification: - // - // > Executable images do not use a string table and do not support - // > section names longer than 8 characters - // - // https://docs.microsoft.com/en-us/windows/win32/debug/pe-format - // - // As a result, we choose a slightly shorter name! As to why - // `.note.rustc` works on MinGW, that's another good question... - - if target.is_like_osx { "__DATA,.rustc" } else { ".rustc" } -} - -fn read_metadata_section_name(_target: &Target) -> &'static str { - ".rustc" -} diff --git a/compiler/rustc_codegen_ssa/Cargo.toml b/compiler/rustc_codegen_ssa/Cargo.toml index c6764662fa5..68f40d5f863 100644 --- a/compiler/rustc_codegen_ssa/Cargo.toml +++ b/compiler/rustc_codegen_ssa/Cargo.toml @@ -33,3 +33,8 @@ rustc_index = { path = "../rustc_index" } rustc_macros = { path = "../rustc_macros" } rustc_target = { path = "../rustc_target" } rustc_session = { path = "../rustc_session" } + +[dependencies.object] +version = "0.22.0" +default-features = false +features = ["read_core", "elf", "macho", "pe", "unaligned", "archive"] diff --git a/compiler/rustc_codegen_ssa/src/back/metadata.rs b/compiler/rustc_codegen_ssa/src/back/metadata.rs new file mode 100644 index 00000000000..37d1f8ecc83 --- /dev/null +++ b/compiler/rustc_codegen_ssa/src/back/metadata.rs @@ -0,0 +1,71 @@ +//! Reading of the rustc metadata for rlibs and dylibs + +use std::fs::File; +use std::path::Path; + +use rustc_data_structures::memmap::Mmap; +use rustc_data_structures::owning_ref::OwningRef; +use rustc_data_structures::rustc_erase_owner; +use rustc_data_structures::sync::MetadataRef; +use rustc_middle::middle::cstore::MetadataLoader; +use rustc_target::spec::Target; + +use crate::METADATA_FILENAME; + +/// The default metadata loader. This is used by cg_llvm and cg_clif. +/// +/// # Metadata location +/// +/// <dl> +/// <dt>rlib</dt> +/// <dd>The metadata can be found in the `lib.rmeta` file inside of the ar archive.</dd> +/// <dt>dylib</dt> +/// <dd>The metadata can be found in the `.rustc` section of the shared library.</dd> +/// </dl> +pub struct DefaultMetadataLoader; + +fn load_metadata_with( + path: &Path, + f: impl for<'a> FnOnce(&'a [u8]) -> Result<&'a [u8], String>, +) -> Result<MetadataRef, String> { + let file = + File::open(path).map_err(|e| format!("failed to open file '{}': {}", path.display(), e))?; + let data = unsafe { Mmap::map(file) } + .map_err(|e| format!("failed to mmap file '{}': {}", path.display(), e))?; + let metadata = OwningRef::new(data).try_map(f)?; + return Ok(rustc_erase_owner!(metadata.map_owner_box())); +} + +impl MetadataLoader for DefaultMetadataLoader { + fn get_rlib_metadata(&self, _target: &Target, path: &Path) -> Result<MetadataRef, String> { + load_metadata_with(path, |data| { + let archive = object::read::archive::ArchiveFile::parse(&*data) + .map_err(|e| format!("failed to parse rlib '{}': {}", path.display(), e))?; + + for entry_result in archive.members() { + let entry = entry_result + .map_err(|e| format!("failed to parse rlib '{}': {}", path.display(), e))?; + if entry.name() == METADATA_FILENAME.as_bytes() { + return Ok(entry.data()); + } + } + + Err(format!("metadata not found in rlib '{}'", path.display())) + }) + } + + fn get_dylib_metadata(&self, _target: &Target, path: &Path) -> Result<MetadataRef, String> { + use object::{Object, ObjectSection}; + + load_metadata_with(path, |data| { + let file = object::File::parse(&data) + .map_err(|e| format!("failed to parse dylib '{}': {}", path.display(), e))?; + file.section_by_name(".rustc") + .ok_or_else(|| format!("no .rustc section in '{}'", path.display()))? + .data() + .map_err(|e| { + format!("failed to read .rustc section in '{}': {}", path.display(), e) + }) + }) + } +} diff --git a/compiler/rustc_codegen_ssa/src/back/mod.rs b/compiler/rustc_codegen_ssa/src/back/mod.rs index 20ca503d43f..d11ed54eb20 100644 --- a/compiler/rustc_codegen_ssa/src/back/mod.rs +++ b/compiler/rustc_codegen_ssa/src/back/mod.rs @@ -3,6 +3,7 @@ pub mod command; pub mod link; pub mod linker; pub mod lto; +pub mod metadata; pub mod rpath; pub mod symbol_export; pub mod write; diff --git a/src/test/run-make-fulldeps/hotplug_codegen_backend/the_backend.rs b/src/test/run-make-fulldeps/hotplug_codegen_backend/the_backend.rs index 684e9760cc6..a9e99d3c10e 100644 --- a/src/test/run-make-fulldeps/hotplug_codegen_backend/the_backend.rs +++ b/src/test/run-make-fulldeps/hotplug_codegen_backend/the_backend.rs @@ -28,23 +28,11 @@ use rustc_target::spec::Target; use std::any::Any; use std::path::Path; -pub struct NoLlvmMetadataLoader; - -impl MetadataLoader for NoLlvmMetadataLoader { - fn get_rlib_metadata(&self, _: &Target, filename: &Path) -> Result<MetadataRef, String> { - unreachable!("some_crate.rs shouldn't depend on any external crates"); - } - - fn get_dylib_metadata(&self, target: &Target, filename: &Path) -> Result<MetadataRef, String> { - unreachable!("some_crate.rs shouldn't depend on any external crates"); - } -} - struct TheBackend; impl CodegenBackend for TheBackend { fn metadata_loader(&self) -> Box<MetadataLoaderDyn> { - Box::new(NoLlvmMetadataLoader) + Box::new(rustc_codegen_ssa::back::metadata::DefaultMetadataLoader) } fn provide(&self, providers: &mut Providers) {} |