1c1d2e44c5
Stabilize linker-plugin based LTO (aka cross-language LTO) This PR stabilizes [linker plugin based LTO](https://github.com/rust-lang/rust/issues/49879), also known as "cross-language LTO" because it allows for doing inlining and other optimizations across language boundaries in mixed Rust/C/C++ projects. As described in the tracking issue, it works by making `rustc` emit LLVM bitcode instead of machine code, the same as `clang` does. A linker with the proper plugin (like LLD) can then run (Thin)LTO across all modules. The feature has been implemented over a number of pull requests and there are various [codegen](https://github.com/rust-lang/rust/blob/master/src/test/codegen/no-dllimport-w-cross-lang-lto.rs) and [run](https://github.com/rust-lang/rust/tree/master/src/test/run-make-fulldeps/cross-lang-lto-clang)-[make](https://github.com/rust-lang/rust/tree/master/src/test/run-make-fulldeps/cross-lang-lto-upstream-rlibs) [tests](https://github.com/rust-lang/rust/tree/master/src/test/run-make-fulldeps/cross-lang-lto) that make sure that it keeps working. It also works for building big projects like [Firefox](https://treeherder.mozilla.org/#/jobs?repo=try&revision=2ce2d5ddcea6fbff790503eac406954e469b2f5d). The PR makes the feature available under the `-C linker-plugin-lto` flag. As discussed in the tracking issue it is not cross-language specific and also not LLD specific. `-C linker-plugin-lto` is descriptive of what it does. If someone has a better name, let me know `:)`
1897 lines
76 KiB
Rust
1897 lines
76 KiB
Rust
use crate::{ModuleCodegen, ModuleKind, CachedModuleCodegen, CompiledModule, CrateInfo,
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CodegenResults, RLIB_BYTECODE_EXTENSION};
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use super::linker::LinkerInfo;
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use super::lto::{self, SerializedModule};
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use super::link::{self, remove, get_linker};
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use super::command::Command;
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use super::symbol_export::ExportedSymbols;
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use crate::traits::*;
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use rustc_incremental::{copy_cgu_workproducts_to_incr_comp_cache_dir,
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in_incr_comp_dir, in_incr_comp_dir_sess};
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use rustc::dep_graph::{WorkProduct, WorkProductId, WorkProductFileKind};
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use rustc::dep_graph::cgu_reuse_tracker::CguReuseTracker;
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use rustc::middle::cstore::EncodedMetadata;
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use rustc::session::config::{self, OutputFilenames, OutputType, Passes, Sanitizer, Lto};
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use rustc::session::Session;
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use rustc::util::nodemap::FxHashMap;
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use rustc::util::time_graph::{self, TimeGraph, Timeline};
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use rustc::hir::def_id::{CrateNum, LOCAL_CRATE};
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use rustc::ty::TyCtxt;
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use rustc::util::common::{time_depth, set_time_depth, print_time_passes_entry};
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use rustc_fs_util::link_or_copy;
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use rustc_data_structures::svh::Svh;
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use rustc_errors::{Handler, Level, DiagnosticBuilder, FatalError, DiagnosticId};
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use rustc_errors::emitter::{Emitter};
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use rustc_target::spec::MergeFunctions;
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use syntax::attr;
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use syntax::ext::hygiene::Mark;
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use syntax_pos::MultiSpan;
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use syntax_pos::symbol::Symbol;
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use jobserver::{Client, Acquired};
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use std::any::Any;
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use std::fs;
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use std::io;
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use std::mem;
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use std::path::{Path, PathBuf};
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use std::str;
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use std::sync::Arc;
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use std::sync::mpsc::{channel, Sender, Receiver};
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use std::time::Instant;
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use std::thread;
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const PRE_THIN_LTO_BC_EXT: &str = "pre-thin-lto.bc";
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/// Module-specific configuration for `optimize_and_codegen`.
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pub struct ModuleConfig {
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/// Names of additional optimization passes to run.
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pub passes: Vec<String>,
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/// Some(level) to optimize at a certain level, or None to run
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/// absolutely no optimizations (used for the metadata module).
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pub opt_level: Option<config::OptLevel>,
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/// Some(level) to optimize binary size, or None to not affect program size.
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pub opt_size: Option<config::OptLevel>,
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pub pgo_gen: Option<String>,
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pub pgo_use: String,
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// Flags indicating which outputs to produce.
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pub emit_pre_thin_lto_bc: bool,
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pub emit_no_opt_bc: bool,
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pub emit_bc: bool,
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pub emit_bc_compressed: bool,
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pub emit_lto_bc: bool,
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pub emit_ir: bool,
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pub emit_asm: bool,
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pub emit_obj: bool,
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// Miscellaneous flags. These are mostly copied from command-line
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// options.
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pub verify_llvm_ir: bool,
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pub no_prepopulate_passes: bool,
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pub no_builtins: bool,
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pub time_passes: bool,
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pub vectorize_loop: bool,
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pub vectorize_slp: bool,
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pub merge_functions: bool,
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pub inline_threshold: Option<usize>,
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// Instead of creating an object file by doing LLVM codegen, just
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// make the object file bitcode. Provides easy compatibility with
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// emscripten's ecc compiler, when used as the linker.
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pub obj_is_bitcode: bool,
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pub no_integrated_as: bool,
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pub embed_bitcode: bool,
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pub embed_bitcode_marker: bool,
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}
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impl ModuleConfig {
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fn new(passes: Vec<String>) -> ModuleConfig {
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ModuleConfig {
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passes,
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opt_level: None,
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opt_size: None,
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pgo_gen: None,
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pgo_use: String::new(),
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emit_no_opt_bc: false,
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emit_pre_thin_lto_bc: false,
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emit_bc: false,
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emit_bc_compressed: false,
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emit_lto_bc: false,
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emit_ir: false,
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emit_asm: false,
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emit_obj: false,
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obj_is_bitcode: false,
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embed_bitcode: false,
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embed_bitcode_marker: false,
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no_integrated_as: false,
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verify_llvm_ir: false,
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no_prepopulate_passes: false,
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no_builtins: false,
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time_passes: false,
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vectorize_loop: false,
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vectorize_slp: false,
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merge_functions: false,
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inline_threshold: None
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}
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}
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fn set_flags(&mut self, sess: &Session, no_builtins: bool) {
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self.verify_llvm_ir = sess.verify_llvm_ir();
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self.no_prepopulate_passes = sess.opts.cg.no_prepopulate_passes;
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self.no_builtins = no_builtins || sess.target.target.options.no_builtins;
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self.time_passes = sess.time_passes();
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self.inline_threshold = sess.opts.cg.inline_threshold;
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self.obj_is_bitcode = sess.target.target.options.obj_is_bitcode ||
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sess.opts.cg.linker_plugin_lto.enabled();
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let embed_bitcode = sess.target.target.options.embed_bitcode ||
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sess.opts.debugging_opts.embed_bitcode;
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if embed_bitcode {
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match sess.opts.optimize {
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config::OptLevel::No |
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config::OptLevel::Less => {
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self.embed_bitcode_marker = embed_bitcode;
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}
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_ => self.embed_bitcode = embed_bitcode,
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}
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}
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// Copy what clang does by turning on loop vectorization at O2 and
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// slp vectorization at O3. Otherwise configure other optimization aspects
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// of this pass manager builder.
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// Turn off vectorization for emscripten, as it's not very well supported.
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self.vectorize_loop = !sess.opts.cg.no_vectorize_loops &&
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(sess.opts.optimize == config::OptLevel::Default ||
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sess.opts.optimize == config::OptLevel::Aggressive) &&
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!sess.target.target.options.is_like_emscripten;
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self.vectorize_slp = !sess.opts.cg.no_vectorize_slp &&
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sess.opts.optimize == config::OptLevel::Aggressive &&
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!sess.target.target.options.is_like_emscripten;
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// Some targets (namely, NVPTX) interact badly with the MergeFunctions
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// pass. This is because MergeFunctions can generate new function calls
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// which may interfere with the target calling convention; e.g. for the
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// NVPTX target, PTX kernels should not call other PTX kernels.
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// MergeFunctions can also be configured to generate aliases instead,
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// but aliases are not supported by some backends (again, NVPTX).
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// Therefore, allow targets to opt out of the MergeFunctions pass,
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// but otherwise keep the pass enabled (at O2 and O3) since it can be
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// useful for reducing code size.
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self.merge_functions = match sess.opts.debugging_opts.merge_functions
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.unwrap_or(sess.target.target.options.merge_functions) {
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MergeFunctions::Disabled => false,
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MergeFunctions::Trampolines |
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MergeFunctions::Aliases => {
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sess.opts.optimize == config::OptLevel::Default ||
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sess.opts.optimize == config::OptLevel::Aggressive
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}
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};
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}
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pub fn bitcode_needed(&self) -> bool {
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self.emit_bc || self.obj_is_bitcode
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|| self.emit_bc_compressed || self.embed_bitcode
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}
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}
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/// Assembler name and command used by codegen when no_integrated_as is enabled
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pub struct AssemblerCommand {
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name: PathBuf,
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cmd: Command,
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}
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// HACK(eddyb) work around `#[derive]` producing wrong bounds for `Clone`.
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pub struct TargetMachineFactory<B: WriteBackendMethods>(
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pub Arc<dyn Fn() -> Result<B::TargetMachine, String> + Send + Sync>,
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);
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impl<B: WriteBackendMethods> Clone for TargetMachineFactory<B> {
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fn clone(&self) -> Self {
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TargetMachineFactory(self.0.clone())
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}
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}
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/// Additional resources used by optimize_and_codegen (not module specific)
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#[derive(Clone)]
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pub struct CodegenContext<B: WriteBackendMethods> {
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// Resources needed when running LTO
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pub backend: B,
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pub time_passes: bool,
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pub lto: Lto,
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pub no_landing_pads: bool,
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pub save_temps: bool,
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pub fewer_names: bool,
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pub exported_symbols: Option<Arc<ExportedSymbols>>,
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pub opts: Arc<config::Options>,
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pub crate_types: Vec<config::CrateType>,
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pub each_linked_rlib_for_lto: Vec<(CrateNum, PathBuf)>,
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pub output_filenames: Arc<OutputFilenames>,
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pub regular_module_config: Arc<ModuleConfig>,
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pub metadata_module_config: Arc<ModuleConfig>,
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pub allocator_module_config: Arc<ModuleConfig>,
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pub tm_factory: TargetMachineFactory<B>,
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pub msvc_imps_needed: bool,
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pub target_pointer_width: String,
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pub debuginfo: config::DebugInfo,
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// Number of cgus excluding the allocator/metadata modules
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pub total_cgus: usize,
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// Handler to use for diagnostics produced during codegen.
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pub diag_emitter: SharedEmitter,
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// LLVM passes added by plugins.
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pub plugin_passes: Vec<String>,
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// LLVM optimizations for which we want to print remarks.
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pub remark: Passes,
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// Worker thread number
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pub worker: usize,
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// The incremental compilation session directory, or None if we are not
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// compiling incrementally
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pub incr_comp_session_dir: Option<PathBuf>,
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// Used to update CGU re-use information during the thinlto phase.
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pub cgu_reuse_tracker: CguReuseTracker,
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// Channel back to the main control thread to send messages to
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pub coordinator_send: Sender<Box<dyn Any + Send>>,
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// A reference to the TimeGraph so we can register timings. None means that
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// measuring is disabled.
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pub time_graph: Option<TimeGraph>,
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// The assembler command if no_integrated_as option is enabled, None otherwise
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pub assembler_cmd: Option<Arc<AssemblerCommand>>
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}
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impl<B: WriteBackendMethods> CodegenContext<B> {
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pub fn create_diag_handler(&self) -> Handler {
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Handler::with_emitter(true, false, Box::new(self.diag_emitter.clone()))
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}
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pub fn config(&self, kind: ModuleKind) -> &ModuleConfig {
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match kind {
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ModuleKind::Regular => &self.regular_module_config,
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ModuleKind::Metadata => &self.metadata_module_config,
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ModuleKind::Allocator => &self.allocator_module_config,
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}
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}
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}
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fn generate_lto_work<B: ExtraBackendMethods>(
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cgcx: &CodegenContext<B>,
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needs_fat_lto: Vec<ModuleCodegen<B::Module>>,
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needs_thin_lto: Vec<(String, B::ThinBuffer)>,
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import_only_modules: Vec<(SerializedModule<B::ModuleBuffer>, WorkProduct)>
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) -> Vec<(WorkItem<B>, u64)> {
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let mut timeline = cgcx.time_graph.as_ref().map(|tg| {
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tg.start(CODEGEN_WORKER_TIMELINE,
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CODEGEN_WORK_PACKAGE_KIND,
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"generate lto")
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}).unwrap_or(Timeline::noop());
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let (lto_modules, copy_jobs) = if !needs_fat_lto.is_empty() {
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assert!(needs_thin_lto.is_empty());
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assert!(import_only_modules.is_empty());
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let lto_module = B::run_fat_lto(cgcx, needs_fat_lto, &mut timeline)
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.unwrap_or_else(|e| e.raise());
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(vec![lto_module], vec![])
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} else {
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assert!(needs_fat_lto.is_empty());
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B::run_thin_lto(cgcx, needs_thin_lto, import_only_modules, &mut timeline)
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.unwrap_or_else(|e| e.raise())
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};
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lto_modules.into_iter().map(|module| {
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let cost = module.cost();
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(WorkItem::LTO(module), cost)
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}).chain(copy_jobs.into_iter().map(|wp| {
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(WorkItem::CopyPostLtoArtifacts(CachedModuleCodegen {
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name: wp.cgu_name.clone(),
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source: wp,
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}), 0)
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})).collect()
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}
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pub struct CompiledModules {
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pub modules: Vec<CompiledModule>,
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pub metadata_module: CompiledModule,
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pub allocator_module: Option<CompiledModule>,
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}
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fn need_crate_bitcode_for_rlib(sess: &Session) -> bool {
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sess.crate_types.borrow().contains(&config::CrateType::Rlib) &&
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sess.opts.output_types.contains_key(&OutputType::Exe)
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}
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fn need_pre_thin_lto_bitcode_for_incr_comp(sess: &Session) -> bool {
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if sess.opts.incremental.is_none() {
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return false
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}
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match sess.lto() {
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Lto::Fat |
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Lto::No => false,
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Lto::Thin |
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Lto::ThinLocal => true,
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}
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}
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pub fn start_async_codegen<B: ExtraBackendMethods>(
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backend: B,
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tcx: TyCtxt,
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time_graph: Option<TimeGraph>,
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metadata: EncodedMetadata,
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coordinator_receive: Receiver<Box<dyn Any + Send>>,
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total_cgus: usize
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) -> OngoingCodegen<B> {
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let sess = tcx.sess;
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let crate_name = tcx.crate_name(LOCAL_CRATE);
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let crate_hash = tcx.crate_hash(LOCAL_CRATE);
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let no_builtins = attr::contains_name(&tcx.hir().krate().attrs, "no_builtins");
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let subsystem = attr::first_attr_value_str_by_name(&tcx.hir().krate().attrs,
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"windows_subsystem");
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let windows_subsystem = subsystem.map(|subsystem| {
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if subsystem != "windows" && subsystem != "console" {
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tcx.sess.fatal(&format!("invalid windows subsystem `{}`, only \
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`windows` and `console` are allowed",
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subsystem));
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}
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subsystem.to_string()
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});
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let linker_info = LinkerInfo::new(tcx);
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let crate_info = CrateInfo::new(tcx);
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// Figure out what we actually need to build.
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let mut modules_config = ModuleConfig::new(sess.opts.cg.passes.clone());
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let mut metadata_config = ModuleConfig::new(vec![]);
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let mut allocator_config = ModuleConfig::new(vec![]);
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if let Some(ref sanitizer) = sess.opts.debugging_opts.sanitizer {
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match *sanitizer {
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Sanitizer::Address => {
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modules_config.passes.push("asan".to_owned());
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modules_config.passes.push("asan-module".to_owned());
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}
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Sanitizer::Memory => {
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modules_config.passes.push("msan".to_owned())
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}
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Sanitizer::Thread => {
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modules_config.passes.push("tsan".to_owned())
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}
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_ => {}
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}
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}
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if sess.opts.debugging_opts.profile {
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modules_config.passes.push("insert-gcov-profiling".to_owned())
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}
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modules_config.pgo_gen = sess.opts.debugging_opts.pgo_gen.clone();
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modules_config.pgo_use = sess.opts.debugging_opts.pgo_use.clone();
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modules_config.opt_level = Some(sess.opts.optimize);
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modules_config.opt_size = Some(sess.opts.optimize);
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// Save all versions of the bytecode if we're saving our temporaries.
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if sess.opts.cg.save_temps {
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modules_config.emit_no_opt_bc = true;
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modules_config.emit_pre_thin_lto_bc = true;
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modules_config.emit_bc = true;
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modules_config.emit_lto_bc = true;
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metadata_config.emit_bc = true;
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allocator_config.emit_bc = true;
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}
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// Emit compressed bitcode files for the crate if we're emitting an rlib.
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// Whenever an rlib is created, the bitcode is inserted into the archive in
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// order to allow LTO against it.
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if need_crate_bitcode_for_rlib(sess) {
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modules_config.emit_bc_compressed = true;
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allocator_config.emit_bc_compressed = true;
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}
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modules_config.emit_pre_thin_lto_bc =
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need_pre_thin_lto_bitcode_for_incr_comp(sess);
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modules_config.no_integrated_as = tcx.sess.opts.cg.no_integrated_as ||
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tcx.sess.target.target.options.no_integrated_as;
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for output_type in sess.opts.output_types.keys() {
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match *output_type {
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OutputType::Bitcode => { modules_config.emit_bc = true; }
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OutputType::LlvmAssembly => { modules_config.emit_ir = true; }
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OutputType::Assembly => {
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modules_config.emit_asm = true;
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// If we're not using the LLVM assembler, this function
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// could be invoked specially with output_type_assembly, so
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// in this case we still want the metadata object file.
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if !sess.opts.output_types.contains_key(&OutputType::Assembly) {
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metadata_config.emit_obj = true;
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allocator_config.emit_obj = true;
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}
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}
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OutputType::Object => { modules_config.emit_obj = true; }
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OutputType::Metadata => { metadata_config.emit_obj = true; }
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OutputType::Exe => {
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modules_config.emit_obj = true;
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metadata_config.emit_obj = true;
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allocator_config.emit_obj = true;
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},
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OutputType::Mir => {}
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OutputType::DepInfo => {}
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}
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}
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modules_config.set_flags(sess, no_builtins);
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metadata_config.set_flags(sess, no_builtins);
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allocator_config.set_flags(sess, no_builtins);
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|
|
// Exclude metadata and allocator modules from time_passes output, since
|
|
// they throw off the "LLVM passes" measurement.
|
|
metadata_config.time_passes = false;
|
|
allocator_config.time_passes = false;
|
|
|
|
let (shared_emitter, shared_emitter_main) = SharedEmitter::new();
|
|
let (codegen_worker_send, codegen_worker_receive) = channel();
|
|
|
|
let coordinator_thread = start_executing_work(backend.clone(),
|
|
tcx,
|
|
&crate_info,
|
|
shared_emitter,
|
|
codegen_worker_send,
|
|
coordinator_receive,
|
|
total_cgus,
|
|
sess.jobserver.clone(),
|
|
time_graph.clone(),
|
|
Arc::new(modules_config),
|
|
Arc::new(metadata_config),
|
|
Arc::new(allocator_config));
|
|
|
|
OngoingCodegen {
|
|
backend,
|
|
crate_name,
|
|
crate_hash,
|
|
metadata,
|
|
windows_subsystem,
|
|
linker_info,
|
|
crate_info,
|
|
|
|
time_graph,
|
|
coordinator_send: tcx.tx_to_llvm_workers.lock().clone(),
|
|
codegen_worker_receive,
|
|
shared_emitter_main,
|
|
future: coordinator_thread,
|
|
output_filenames: tcx.output_filenames(LOCAL_CRATE),
|
|
}
|
|
}
|
|
|
|
fn copy_all_cgu_workproducts_to_incr_comp_cache_dir(
|
|
sess: &Session,
|
|
compiled_modules: &CompiledModules,
|
|
) -> FxHashMap<WorkProductId, WorkProduct> {
|
|
let mut work_products = FxHashMap::default();
|
|
|
|
if sess.opts.incremental.is_none() {
|
|
return work_products;
|
|
}
|
|
|
|
for module in compiled_modules.modules.iter().filter(|m| m.kind == ModuleKind::Regular) {
|
|
let mut files = vec![];
|
|
|
|
if let Some(ref path) = module.object {
|
|
files.push((WorkProductFileKind::Object, path.clone()));
|
|
}
|
|
if let Some(ref path) = module.bytecode {
|
|
files.push((WorkProductFileKind::Bytecode, path.clone()));
|
|
}
|
|
if let Some(ref path) = module.bytecode_compressed {
|
|
files.push((WorkProductFileKind::BytecodeCompressed, path.clone()));
|
|
}
|
|
|
|
if let Some((id, product)) =
|
|
copy_cgu_workproducts_to_incr_comp_cache_dir(sess, &module.name, &files) {
|
|
work_products.insert(id, product);
|
|
}
|
|
}
|
|
|
|
work_products
|
|
}
|
|
|
|
fn produce_final_output_artifacts(sess: &Session,
|
|
compiled_modules: &CompiledModules,
|
|
crate_output: &OutputFilenames) {
|
|
let mut user_wants_bitcode = false;
|
|
let mut user_wants_objects = false;
|
|
|
|
// Produce final compile outputs.
|
|
let copy_gracefully = |from: &Path, to: &Path| {
|
|
if let Err(e) = fs::copy(from, to) {
|
|
sess.err(&format!("could not copy {:?} to {:?}: {}", from, to, e));
|
|
}
|
|
};
|
|
|
|
let copy_if_one_unit = |output_type: OutputType,
|
|
keep_numbered: bool| {
|
|
if compiled_modules.modules.len() == 1 {
|
|
// 1) Only one codegen unit. In this case it's no difficulty
|
|
// to copy `foo.0.x` to `foo.x`.
|
|
let module_name = Some(&compiled_modules.modules[0].name[..]);
|
|
let path = crate_output.temp_path(output_type, module_name);
|
|
copy_gracefully(&path,
|
|
&crate_output.path(output_type));
|
|
if !sess.opts.cg.save_temps && !keep_numbered {
|
|
// The user just wants `foo.x`, not `foo.#module-name#.x`.
|
|
remove(sess, &path);
|
|
}
|
|
} else {
|
|
let ext = crate_output.temp_path(output_type, None)
|
|
.extension()
|
|
.unwrap()
|
|
.to_str()
|
|
.unwrap()
|
|
.to_owned();
|
|
|
|
if crate_output.outputs.contains_key(&output_type) {
|
|
// 2) Multiple codegen units, with `--emit foo=some_name`. We have
|
|
// no good solution for this case, so warn the user.
|
|
sess.warn(&format!("ignoring emit path because multiple .{} files \
|
|
were produced", ext));
|
|
} else if crate_output.single_output_file.is_some() {
|
|
// 3) Multiple codegen units, with `-o some_name`. We have
|
|
// no good solution for this case, so warn the user.
|
|
sess.warn(&format!("ignoring -o because multiple .{} files \
|
|
were produced", ext));
|
|
} else {
|
|
// 4) Multiple codegen units, but no explicit name. We
|
|
// just leave the `foo.0.x` files in place.
|
|
// (We don't have to do any work in this case.)
|
|
}
|
|
}
|
|
};
|
|
|
|
// Flag to indicate whether the user explicitly requested bitcode.
|
|
// Otherwise, we produced it only as a temporary output, and will need
|
|
// to get rid of it.
|
|
for output_type in crate_output.outputs.keys() {
|
|
match *output_type {
|
|
OutputType::Bitcode => {
|
|
user_wants_bitcode = true;
|
|
// Copy to .bc, but always keep the .0.bc. There is a later
|
|
// check to figure out if we should delete .0.bc files, or keep
|
|
// them for making an rlib.
|
|
copy_if_one_unit(OutputType::Bitcode, true);
|
|
}
|
|
OutputType::LlvmAssembly => {
|
|
copy_if_one_unit(OutputType::LlvmAssembly, false);
|
|
}
|
|
OutputType::Assembly => {
|
|
copy_if_one_unit(OutputType::Assembly, false);
|
|
}
|
|
OutputType::Object => {
|
|
user_wants_objects = true;
|
|
copy_if_one_unit(OutputType::Object, true);
|
|
}
|
|
OutputType::Mir |
|
|
OutputType::Metadata |
|
|
OutputType::Exe |
|
|
OutputType::DepInfo => {}
|
|
}
|
|
}
|
|
|
|
// Clean up unwanted temporary files.
|
|
|
|
// We create the following files by default:
|
|
// - #crate#.#module-name#.bc
|
|
// - #crate#.#module-name#.o
|
|
// - #crate#.crate.metadata.bc
|
|
// - #crate#.crate.metadata.o
|
|
// - #crate#.o (linked from crate.##.o)
|
|
// - #crate#.bc (copied from crate.##.bc)
|
|
// We may create additional files if requested by the user (through
|
|
// `-C save-temps` or `--emit=` flags).
|
|
|
|
if !sess.opts.cg.save_temps {
|
|
// Remove the temporary .#module-name#.o objects. If the user didn't
|
|
// explicitly request bitcode (with --emit=bc), and the bitcode is not
|
|
// needed for building an rlib, then we must remove .#module-name#.bc as
|
|
// well.
|
|
|
|
// Specific rules for keeping .#module-name#.bc:
|
|
// - If the user requested bitcode (`user_wants_bitcode`), and
|
|
// codegen_units > 1, then keep it.
|
|
// - If the user requested bitcode but codegen_units == 1, then we
|
|
// can toss .#module-name#.bc because we copied it to .bc earlier.
|
|
// - If we're not building an rlib and the user didn't request
|
|
// bitcode, then delete .#module-name#.bc.
|
|
// If you change how this works, also update back::link::link_rlib,
|
|
// where .#module-name#.bc files are (maybe) deleted after making an
|
|
// rlib.
|
|
let needs_crate_object = crate_output.outputs.contains_key(&OutputType::Exe);
|
|
|
|
let keep_numbered_bitcode = user_wants_bitcode && sess.codegen_units() > 1;
|
|
|
|
let keep_numbered_objects = needs_crate_object ||
|
|
(user_wants_objects && sess.codegen_units() > 1);
|
|
|
|
for module in compiled_modules.modules.iter() {
|
|
if let Some(ref path) = module.object {
|
|
if !keep_numbered_objects {
|
|
remove(sess, path);
|
|
}
|
|
}
|
|
|
|
if let Some(ref path) = module.bytecode {
|
|
if !keep_numbered_bitcode {
|
|
remove(sess, path);
|
|
}
|
|
}
|
|
}
|
|
|
|
if !user_wants_bitcode {
|
|
if let Some(ref path) = compiled_modules.metadata_module.bytecode {
|
|
remove(sess, &path);
|
|
}
|
|
|
|
if let Some(ref allocator_module) = compiled_modules.allocator_module {
|
|
if let Some(ref path) = allocator_module.bytecode {
|
|
remove(sess, path);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// We leave the following files around by default:
|
|
// - #crate#.o
|
|
// - #crate#.crate.metadata.o
|
|
// - #crate#.bc
|
|
// These are used in linking steps and will be cleaned up afterward.
|
|
}
|
|
|
|
pub fn dump_incremental_data(_codegen_results: &CodegenResults) {
|
|
// FIXME(mw): This does not work at the moment because the situation has
|
|
// become more complicated due to incremental LTO. Now a CGU
|
|
// can have more than two caching states.
|
|
// println!("[incremental] Re-using {} out of {} modules",
|
|
// codegen_results.modules.iter().filter(|m| m.pre_existing).count(),
|
|
// codegen_results.modules.len());
|
|
}
|
|
|
|
pub enum WorkItem<B: WriteBackendMethods> {
|
|
/// Optimize a newly codegened, totally unoptimized module.
|
|
Optimize(ModuleCodegen<B::Module>),
|
|
/// Copy the post-LTO artifacts from the incremental cache to the output
|
|
/// directory.
|
|
CopyPostLtoArtifacts(CachedModuleCodegen),
|
|
/// Performs (Thin)LTO on the given module.
|
|
LTO(lto::LtoModuleCodegen<B>),
|
|
}
|
|
|
|
impl<B: WriteBackendMethods> WorkItem<B> {
|
|
pub fn module_kind(&self) -> ModuleKind {
|
|
match *self {
|
|
WorkItem::Optimize(ref m) => m.kind,
|
|
WorkItem::CopyPostLtoArtifacts(_) |
|
|
WorkItem::LTO(_) => ModuleKind::Regular,
|
|
}
|
|
}
|
|
|
|
pub fn name(&self) -> String {
|
|
match *self {
|
|
WorkItem::Optimize(ref m) => format!("optimize: {}", m.name),
|
|
WorkItem::CopyPostLtoArtifacts(ref m) => format!("copy post LTO artifacts: {}", m.name),
|
|
WorkItem::LTO(ref m) => format!("lto: {}", m.name()),
|
|
}
|
|
}
|
|
}
|
|
|
|
enum WorkItemResult<B: WriteBackendMethods> {
|
|
Compiled(CompiledModule),
|
|
NeedsFatLTO(ModuleCodegen<B::Module>),
|
|
NeedsThinLTO(String, B::ThinBuffer),
|
|
}
|
|
|
|
fn execute_work_item<B: ExtraBackendMethods>(
|
|
cgcx: &CodegenContext<B>,
|
|
work_item: WorkItem<B>,
|
|
timeline: &mut Timeline
|
|
) -> Result<WorkItemResult<B>, FatalError> {
|
|
let module_config = cgcx.config(work_item.module_kind());
|
|
|
|
match work_item {
|
|
WorkItem::Optimize(module) => {
|
|
execute_optimize_work_item(cgcx, module, module_config, timeline)
|
|
}
|
|
WorkItem::CopyPostLtoArtifacts(module) => {
|
|
execute_copy_from_cache_work_item(cgcx, module, module_config, timeline)
|
|
}
|
|
WorkItem::LTO(module) => {
|
|
execute_lto_work_item(cgcx, module, module_config, timeline)
|
|
}
|
|
}
|
|
}
|
|
|
|
// Actual LTO type we end up chosing based on multiple factors.
|
|
enum ComputedLtoType {
|
|
No,
|
|
Thin,
|
|
Fat,
|
|
}
|
|
|
|
fn execute_optimize_work_item<B: ExtraBackendMethods>(
|
|
cgcx: &CodegenContext<B>,
|
|
module: ModuleCodegen<B::Module>,
|
|
module_config: &ModuleConfig,
|
|
timeline: &mut Timeline
|
|
) -> Result<WorkItemResult<B>, FatalError> {
|
|
let diag_handler = cgcx.create_diag_handler();
|
|
|
|
unsafe {
|
|
B::optimize(cgcx, &diag_handler, &module, module_config, timeline)?;
|
|
}
|
|
|
|
// After we've done the initial round of optimizations we need to
|
|
// decide whether to synchronously codegen this module or ship it
|
|
// back to the coordinator thread for further LTO processing (which
|
|
// has to wait for all the initial modules to be optimized).
|
|
|
|
// If the linker does LTO, we don't have to do it. Note that we
|
|
// keep doing full LTO, if it is requested, as not to break the
|
|
// assumption that the output will be a single module.
|
|
let linker_does_lto = cgcx.opts.cg.linker_plugin_lto.enabled();
|
|
|
|
// When we're automatically doing ThinLTO for multi-codegen-unit
|
|
// builds we don't actually want to LTO the allocator modules if
|
|
// it shows up. This is due to various linker shenanigans that
|
|
// we'll encounter later.
|
|
let is_allocator = module.kind == ModuleKind::Allocator;
|
|
|
|
// We ignore a request for full crate grath LTO if the cate type
|
|
// is only an rlib, as there is no full crate graph to process,
|
|
// that'll happen later.
|
|
//
|
|
// This use case currently comes up primarily for targets that
|
|
// require LTO so the request for LTO is always unconditionally
|
|
// passed down to the backend, but we don't actually want to do
|
|
// anything about it yet until we've got a final product.
|
|
let is_rlib = cgcx.crate_types.len() == 1
|
|
&& cgcx.crate_types[0] == config::CrateType::Rlib;
|
|
|
|
// Metadata modules never participate in LTO regardless of the lto
|
|
// settings.
|
|
let lto_type = if module.kind == ModuleKind::Metadata {
|
|
ComputedLtoType::No
|
|
} else {
|
|
match cgcx.lto {
|
|
Lto::ThinLocal if !linker_does_lto && !is_allocator
|
|
=> ComputedLtoType::Thin,
|
|
Lto::Thin if !linker_does_lto && !is_rlib
|
|
=> ComputedLtoType::Thin,
|
|
Lto::Fat if !is_rlib => ComputedLtoType::Fat,
|
|
_ => ComputedLtoType::No,
|
|
}
|
|
};
|
|
|
|
Ok(match lto_type {
|
|
ComputedLtoType::No => {
|
|
let module = unsafe {
|
|
B::codegen(cgcx, &diag_handler, module, module_config, timeline)?
|
|
};
|
|
WorkItemResult::Compiled(module)
|
|
}
|
|
ComputedLtoType::Thin => {
|
|
let (name, thin_buffer) = B::prepare_thin(cgcx, module);
|
|
WorkItemResult::NeedsThinLTO(name, thin_buffer)
|
|
}
|
|
ComputedLtoType::Fat => WorkItemResult::NeedsFatLTO(module),
|
|
})
|
|
}
|
|
|
|
fn execute_copy_from_cache_work_item<B: ExtraBackendMethods>(
|
|
cgcx: &CodegenContext<B>,
|
|
module: CachedModuleCodegen,
|
|
module_config: &ModuleConfig,
|
|
_: &mut Timeline
|
|
) -> Result<WorkItemResult<B>, FatalError> {
|
|
let incr_comp_session_dir = cgcx.incr_comp_session_dir
|
|
.as_ref()
|
|
.unwrap();
|
|
let mut object = None;
|
|
let mut bytecode = None;
|
|
let mut bytecode_compressed = None;
|
|
for (kind, saved_file) in &module.source.saved_files {
|
|
let obj_out = match kind {
|
|
WorkProductFileKind::Object => {
|
|
let path = cgcx.output_filenames.temp_path(OutputType::Object,
|
|
Some(&module.name));
|
|
object = Some(path.clone());
|
|
path
|
|
}
|
|
WorkProductFileKind::Bytecode => {
|
|
let path = cgcx.output_filenames.temp_path(OutputType::Bitcode,
|
|
Some(&module.name));
|
|
bytecode = Some(path.clone());
|
|
path
|
|
}
|
|
WorkProductFileKind::BytecodeCompressed => {
|
|
let path = cgcx.output_filenames.temp_path(OutputType::Bitcode,
|
|
Some(&module.name))
|
|
.with_extension(RLIB_BYTECODE_EXTENSION);
|
|
bytecode_compressed = Some(path.clone());
|
|
path
|
|
}
|
|
};
|
|
let source_file = in_incr_comp_dir(&incr_comp_session_dir,
|
|
&saved_file);
|
|
debug!("copying pre-existing module `{}` from {:?} to {}",
|
|
module.name,
|
|
source_file,
|
|
obj_out.display());
|
|
if let Err(err) = link_or_copy(&source_file, &obj_out) {
|
|
let diag_handler = cgcx.create_diag_handler();
|
|
diag_handler.err(&format!("unable to copy {} to {}: {}",
|
|
source_file.display(),
|
|
obj_out.display(),
|
|
err));
|
|
}
|
|
}
|
|
|
|
assert_eq!(object.is_some(), module_config.emit_obj);
|
|
assert_eq!(bytecode.is_some(), module_config.emit_bc);
|
|
assert_eq!(bytecode_compressed.is_some(), module_config.emit_bc_compressed);
|
|
|
|
Ok(WorkItemResult::Compiled(CompiledModule {
|
|
name: module.name,
|
|
kind: ModuleKind::Regular,
|
|
object,
|
|
bytecode,
|
|
bytecode_compressed,
|
|
}))
|
|
}
|
|
|
|
fn execute_lto_work_item<B: ExtraBackendMethods>(
|
|
cgcx: &CodegenContext<B>,
|
|
mut module: lto::LtoModuleCodegen<B>,
|
|
module_config: &ModuleConfig,
|
|
timeline: &mut Timeline
|
|
) -> Result<WorkItemResult<B>, FatalError> {
|
|
let diag_handler = cgcx.create_diag_handler();
|
|
|
|
unsafe {
|
|
let module = module.optimize(cgcx, timeline)?;
|
|
let module = B::codegen(cgcx, &diag_handler, module, module_config, timeline)?;
|
|
Ok(WorkItemResult::Compiled(module))
|
|
}
|
|
}
|
|
|
|
pub enum Message<B: WriteBackendMethods> {
|
|
Token(io::Result<Acquired>),
|
|
NeedsFatLTO {
|
|
result: ModuleCodegen<B::Module>,
|
|
worker_id: usize,
|
|
},
|
|
NeedsThinLTO {
|
|
name: String,
|
|
thin_buffer: B::ThinBuffer,
|
|
worker_id: usize,
|
|
},
|
|
Done {
|
|
result: Result<CompiledModule, ()>,
|
|
worker_id: usize,
|
|
},
|
|
CodegenDone {
|
|
llvm_work_item: WorkItem<B>,
|
|
cost: u64,
|
|
},
|
|
AddImportOnlyModule {
|
|
module_data: SerializedModule<B::ModuleBuffer>,
|
|
work_product: WorkProduct,
|
|
},
|
|
CodegenComplete,
|
|
CodegenItem,
|
|
CodegenAborted,
|
|
}
|
|
|
|
struct Diagnostic {
|
|
msg: String,
|
|
code: Option<DiagnosticId>,
|
|
lvl: Level,
|
|
}
|
|
|
|
#[derive(PartialEq, Clone, Copy, Debug)]
|
|
enum MainThreadWorkerState {
|
|
Idle,
|
|
Codegenning,
|
|
LLVMing,
|
|
}
|
|
|
|
fn start_executing_work<B: ExtraBackendMethods>(
|
|
backend: B,
|
|
tcx: TyCtxt,
|
|
crate_info: &CrateInfo,
|
|
shared_emitter: SharedEmitter,
|
|
codegen_worker_send: Sender<Message<B>>,
|
|
coordinator_receive: Receiver<Box<dyn Any + Send>>,
|
|
total_cgus: usize,
|
|
jobserver: Client,
|
|
time_graph: Option<TimeGraph>,
|
|
modules_config: Arc<ModuleConfig>,
|
|
metadata_config: Arc<ModuleConfig>,
|
|
allocator_config: Arc<ModuleConfig>
|
|
) -> thread::JoinHandle<Result<CompiledModules, ()>> {
|
|
let coordinator_send = tcx.tx_to_llvm_workers.lock().clone();
|
|
let sess = tcx.sess;
|
|
|
|
// Compute the set of symbols we need to retain when doing LTO (if we need to)
|
|
let exported_symbols = {
|
|
let mut exported_symbols = FxHashMap::default();
|
|
|
|
let copy_symbols = |cnum| {
|
|
let symbols = tcx.exported_symbols(cnum)
|
|
.iter()
|
|
.map(|&(s, lvl)| (s.symbol_name(tcx).to_string(), lvl))
|
|
.collect();
|
|
Arc::new(symbols)
|
|
};
|
|
|
|
match sess.lto() {
|
|
Lto::No => None,
|
|
Lto::ThinLocal => {
|
|
exported_symbols.insert(LOCAL_CRATE, copy_symbols(LOCAL_CRATE));
|
|
Some(Arc::new(exported_symbols))
|
|
}
|
|
Lto::Fat | Lto::Thin => {
|
|
exported_symbols.insert(LOCAL_CRATE, copy_symbols(LOCAL_CRATE));
|
|
for &cnum in tcx.crates().iter() {
|
|
exported_symbols.insert(cnum, copy_symbols(cnum));
|
|
}
|
|
Some(Arc::new(exported_symbols))
|
|
}
|
|
}
|
|
};
|
|
|
|
// First up, convert our jobserver into a helper thread so we can use normal
|
|
// mpsc channels to manage our messages and such.
|
|
// After we've requested tokens then we'll, when we can,
|
|
// get tokens on `coordinator_receive` which will
|
|
// get managed in the main loop below.
|
|
let coordinator_send2 = coordinator_send.clone();
|
|
let helper = jobserver.into_helper_thread(move |token| {
|
|
drop(coordinator_send2.send(Box::new(Message::Token::<B>(token))));
|
|
}).expect("failed to spawn helper thread");
|
|
|
|
let mut each_linked_rlib_for_lto = Vec::new();
|
|
drop(link::each_linked_rlib(sess, crate_info, &mut |cnum, path| {
|
|
if link::ignored_for_lto(sess, crate_info, cnum) {
|
|
return
|
|
}
|
|
each_linked_rlib_for_lto.push((cnum, path.to_path_buf()));
|
|
}));
|
|
|
|
let assembler_cmd = if modules_config.no_integrated_as {
|
|
// HACK: currently we use linker (gcc) as our assembler
|
|
let (linker, flavor) = link::linker_and_flavor(sess);
|
|
|
|
let (name, mut cmd) = get_linker(sess, &linker, flavor);
|
|
cmd.args(&sess.target.target.options.asm_args);
|
|
Some(Arc::new(AssemblerCommand {
|
|
name,
|
|
cmd,
|
|
}))
|
|
} else {
|
|
None
|
|
};
|
|
|
|
let ol = tcx.backend_optimization_level(LOCAL_CRATE);
|
|
let cgcx = CodegenContext::<B> {
|
|
backend: backend.clone(),
|
|
crate_types: sess.crate_types.borrow().clone(),
|
|
each_linked_rlib_for_lto,
|
|
lto: sess.lto(),
|
|
no_landing_pads: sess.no_landing_pads(),
|
|
fewer_names: sess.fewer_names(),
|
|
save_temps: sess.opts.cg.save_temps,
|
|
opts: Arc::new(sess.opts.clone()),
|
|
time_passes: sess.time_passes(),
|
|
exported_symbols,
|
|
plugin_passes: sess.plugin_llvm_passes.borrow().clone(),
|
|
remark: sess.opts.cg.remark.clone(),
|
|
worker: 0,
|
|
incr_comp_session_dir: sess.incr_comp_session_dir_opt().map(|r| r.clone()),
|
|
cgu_reuse_tracker: sess.cgu_reuse_tracker.clone(),
|
|
coordinator_send,
|
|
diag_emitter: shared_emitter.clone(),
|
|
time_graph,
|
|
output_filenames: tcx.output_filenames(LOCAL_CRATE),
|
|
regular_module_config: modules_config,
|
|
metadata_module_config: metadata_config,
|
|
allocator_module_config: allocator_config,
|
|
tm_factory: TargetMachineFactory(backend.target_machine_factory(tcx.sess, ol, false)),
|
|
total_cgus,
|
|
msvc_imps_needed: msvc_imps_needed(tcx),
|
|
target_pointer_width: tcx.sess.target.target.target_pointer_width.clone(),
|
|
debuginfo: tcx.sess.opts.debuginfo,
|
|
assembler_cmd,
|
|
};
|
|
|
|
// This is the "main loop" of parallel work happening for parallel codegen.
|
|
// It's here that we manage parallelism, schedule work, and work with
|
|
// messages coming from clients.
|
|
//
|
|
// There are a few environmental pre-conditions that shape how the system
|
|
// is set up:
|
|
//
|
|
// - Error reporting only can happen on the main thread because that's the
|
|
// only place where we have access to the compiler `Session`.
|
|
// - LLVM work can be done on any thread.
|
|
// - Codegen can only happen on the main thread.
|
|
// - Each thread doing substantial work most be in possession of a `Token`
|
|
// from the `Jobserver`.
|
|
// - The compiler process always holds one `Token`. Any additional `Tokens`
|
|
// have to be requested from the `Jobserver`.
|
|
//
|
|
// Error Reporting
|
|
// ===============
|
|
// The error reporting restriction is handled separately from the rest: We
|
|
// set up a `SharedEmitter` the holds an open channel to the main thread.
|
|
// When an error occurs on any thread, the shared emitter will send the
|
|
// error message to the receiver main thread (`SharedEmitterMain`). The
|
|
// main thread will periodically query this error message queue and emit
|
|
// any error messages it has received. It might even abort compilation if
|
|
// has received a fatal error. In this case we rely on all other threads
|
|
// being torn down automatically with the main thread.
|
|
// Since the main thread will often be busy doing codegen work, error
|
|
// reporting will be somewhat delayed, since the message queue can only be
|
|
// checked in between to work packages.
|
|
//
|
|
// Work Processing Infrastructure
|
|
// ==============================
|
|
// The work processing infrastructure knows three major actors:
|
|
//
|
|
// - the coordinator thread,
|
|
// - the main thread, and
|
|
// - LLVM worker threads
|
|
//
|
|
// The coordinator thread is running a message loop. It instructs the main
|
|
// thread about what work to do when, and it will spawn off LLVM worker
|
|
// threads as open LLVM WorkItems become available.
|
|
//
|
|
// The job of the main thread is to codegen CGUs into LLVM work package
|
|
// (since the main thread is the only thread that can do this). The main
|
|
// thread will block until it receives a message from the coordinator, upon
|
|
// which it will codegen one CGU, send it to the coordinator and block
|
|
// again. This way the coordinator can control what the main thread is
|
|
// doing.
|
|
//
|
|
// The coordinator keeps a queue of LLVM WorkItems, and when a `Token` is
|
|
// available, it will spawn off a new LLVM worker thread and let it process
|
|
// that a WorkItem. When a LLVM worker thread is done with its WorkItem,
|
|
// it will just shut down, which also frees all resources associated with
|
|
// the given LLVM module, and sends a message to the coordinator that the
|
|
// has been completed.
|
|
//
|
|
// Work Scheduling
|
|
// ===============
|
|
// The scheduler's goal is to minimize the time it takes to complete all
|
|
// work there is, however, we also want to keep memory consumption low
|
|
// if possible. These two goals are at odds with each other: If memory
|
|
// consumption were not an issue, we could just let the main thread produce
|
|
// LLVM WorkItems at full speed, assuring maximal utilization of
|
|
// Tokens/LLVM worker threads. However, since codegen usual is faster
|
|
// than LLVM processing, the queue of LLVM WorkItems would fill up and each
|
|
// WorkItem potentially holds on to a substantial amount of memory.
|
|
//
|
|
// So the actual goal is to always produce just enough LLVM WorkItems as
|
|
// not to starve our LLVM worker threads. That means, once we have enough
|
|
// WorkItems in our queue, we can block the main thread, so it does not
|
|
// produce more until we need them.
|
|
//
|
|
// Doing LLVM Work on the Main Thread
|
|
// ----------------------------------
|
|
// Since the main thread owns the compiler processes implicit `Token`, it is
|
|
// wasteful to keep it blocked without doing any work. Therefore, what we do
|
|
// in this case is: We spawn off an additional LLVM worker thread that helps
|
|
// reduce the queue. The work it is doing corresponds to the implicit
|
|
// `Token`. The coordinator will mark the main thread as being busy with
|
|
// LLVM work. (The actual work happens on another OS thread but we just care
|
|
// about `Tokens`, not actual threads).
|
|
//
|
|
// When any LLVM worker thread finishes while the main thread is marked as
|
|
// "busy with LLVM work", we can do a little switcheroo: We give the Token
|
|
// of the just finished thread to the LLVM worker thread that is working on
|
|
// behalf of the main thread's implicit Token, thus freeing up the main
|
|
// thread again. The coordinator can then again decide what the main thread
|
|
// should do. This allows the coordinator to make decisions at more points
|
|
// in time.
|
|
//
|
|
// Striking a Balance between Throughput and Memory Consumption
|
|
// ------------------------------------------------------------
|
|
// Since our two goals, (1) use as many Tokens as possible and (2) keep
|
|
// memory consumption as low as possible, are in conflict with each other,
|
|
// we have to find a trade off between them. Right now, the goal is to keep
|
|
// all workers busy, which means that no worker should find the queue empty
|
|
// when it is ready to start.
|
|
// How do we do achieve this? Good question :) We actually never know how
|
|
// many `Tokens` are potentially available so it's hard to say how much to
|
|
// fill up the queue before switching the main thread to LLVM work. Also we
|
|
// currently don't have a means to estimate how long a running LLVM worker
|
|
// will still be busy with it's current WorkItem. However, we know the
|
|
// maximal count of available Tokens that makes sense (=the number of CPU
|
|
// cores), so we can take a conservative guess. The heuristic we use here
|
|
// is implemented in the `queue_full_enough()` function.
|
|
//
|
|
// Some Background on Jobservers
|
|
// -----------------------------
|
|
// It's worth also touching on the management of parallelism here. We don't
|
|
// want to just spawn a thread per work item because while that's optimal
|
|
// parallelism it may overload a system with too many threads or violate our
|
|
// configuration for the maximum amount of cpu to use for this process. To
|
|
// manage this we use the `jobserver` crate.
|
|
//
|
|
// Job servers are an artifact of GNU make and are used to manage
|
|
// parallelism between processes. A jobserver is a glorified IPC semaphore
|
|
// basically. Whenever we want to run some work we acquire the semaphore,
|
|
// and whenever we're done with that work we release the semaphore. In this
|
|
// manner we can ensure that the maximum number of parallel workers is
|
|
// capped at any one point in time.
|
|
//
|
|
// LTO and the coordinator thread
|
|
// ------------------------------
|
|
//
|
|
// The final job the coordinator thread is responsible for is managing LTO
|
|
// and how that works. When LTO is requested what we'll to is collect all
|
|
// optimized LLVM modules into a local vector on the coordinator. Once all
|
|
// modules have been codegened and optimized we hand this to the `lto`
|
|
// module for further optimization. The `lto` module will return back a list
|
|
// of more modules to work on, which the coordinator will continue to spawn
|
|
// work for.
|
|
//
|
|
// Each LLVM module is automatically sent back to the coordinator for LTO if
|
|
// necessary. There's already optimizations in place to avoid sending work
|
|
// back to the coordinator if LTO isn't requested.
|
|
return thread::spawn(move || {
|
|
// We pretend to be within the top-level LLVM time-passes task here:
|
|
set_time_depth(1);
|
|
|
|
let max_workers = ::num_cpus::get();
|
|
let mut worker_id_counter = 0;
|
|
let mut free_worker_ids = Vec::new();
|
|
let mut get_worker_id = |free_worker_ids: &mut Vec<usize>| {
|
|
if let Some(id) = free_worker_ids.pop() {
|
|
id
|
|
} else {
|
|
let id = worker_id_counter;
|
|
worker_id_counter += 1;
|
|
id
|
|
}
|
|
};
|
|
|
|
// This is where we collect codegen units that have gone all the way
|
|
// through codegen and LLVM.
|
|
let mut compiled_modules = vec![];
|
|
let mut compiled_metadata_module = None;
|
|
let mut compiled_allocator_module = None;
|
|
let mut needs_fat_lto = Vec::new();
|
|
let mut needs_thin_lto = Vec::new();
|
|
let mut lto_import_only_modules = Vec::new();
|
|
let mut started_lto = false;
|
|
let mut codegen_aborted = false;
|
|
|
|
// This flag tracks whether all items have gone through codegens
|
|
let mut codegen_done = false;
|
|
|
|
// This is the queue of LLVM work items that still need processing.
|
|
let mut work_items = Vec::<(WorkItem<B>, u64)>::new();
|
|
|
|
// This are the Jobserver Tokens we currently hold. Does not include
|
|
// the implicit Token the compiler process owns no matter what.
|
|
let mut tokens = Vec::new();
|
|
|
|
let mut main_thread_worker_state = MainThreadWorkerState::Idle;
|
|
let mut running = 0;
|
|
|
|
let mut llvm_start_time = None;
|
|
|
|
// Run the message loop while there's still anything that needs message
|
|
// processing. Note that as soon as codegen is aborted we simply want to
|
|
// wait for all existing work to finish, so many of the conditions here
|
|
// only apply if codegen hasn't been aborted as they represent pending
|
|
// work to be done.
|
|
while !codegen_done ||
|
|
running > 0 ||
|
|
(!codegen_aborted && (
|
|
work_items.len() > 0 ||
|
|
needs_fat_lto.len() > 0 ||
|
|
needs_thin_lto.len() > 0 ||
|
|
lto_import_only_modules.len() > 0 ||
|
|
main_thread_worker_state != MainThreadWorkerState::Idle
|
|
))
|
|
{
|
|
|
|
// While there are still CGUs to be codegened, the coordinator has
|
|
// to decide how to utilize the compiler processes implicit Token:
|
|
// For codegenning more CGU or for running them through LLVM.
|
|
if !codegen_done {
|
|
if main_thread_worker_state == MainThreadWorkerState::Idle {
|
|
if !queue_full_enough(work_items.len(), running, max_workers) {
|
|
// The queue is not full enough, codegen more items:
|
|
if let Err(_) = codegen_worker_send.send(Message::CodegenItem) {
|
|
panic!("Could not send Message::CodegenItem to main thread")
|
|
}
|
|
main_thread_worker_state = MainThreadWorkerState::Codegenning;
|
|
} else {
|
|
// The queue is full enough to not let the worker
|
|
// threads starve. Use the implicit Token to do some
|
|
// LLVM work too.
|
|
let (item, _) = work_items.pop()
|
|
.expect("queue empty - queue_full_enough() broken?");
|
|
let cgcx = CodegenContext {
|
|
worker: get_worker_id(&mut free_worker_ids),
|
|
.. cgcx.clone()
|
|
};
|
|
maybe_start_llvm_timer(cgcx.config(item.module_kind()),
|
|
&mut llvm_start_time);
|
|
main_thread_worker_state = MainThreadWorkerState::LLVMing;
|
|
spawn_work(cgcx, item);
|
|
}
|
|
}
|
|
} else if codegen_aborted {
|
|
// don't queue up any more work if codegen was aborted, we're
|
|
// just waiting for our existing children to finish
|
|
} else {
|
|
// If we've finished everything related to normal codegen
|
|
// then it must be the case that we've got some LTO work to do.
|
|
// Perform the serial work here of figuring out what we're
|
|
// going to LTO and then push a bunch of work items onto our
|
|
// queue to do LTO
|
|
if work_items.len() == 0 &&
|
|
running == 0 &&
|
|
main_thread_worker_state == MainThreadWorkerState::Idle {
|
|
assert!(!started_lto);
|
|
started_lto = true;
|
|
|
|
let needs_fat_lto =
|
|
mem::replace(&mut needs_fat_lto, Vec::new());
|
|
let needs_thin_lto =
|
|
mem::replace(&mut needs_thin_lto, Vec::new());
|
|
let import_only_modules =
|
|
mem::replace(&mut lto_import_only_modules, Vec::new());
|
|
|
|
for (work, cost) in generate_lto_work(&cgcx, needs_fat_lto,
|
|
needs_thin_lto, import_only_modules) {
|
|
let insertion_index = work_items
|
|
.binary_search_by_key(&cost, |&(_, cost)| cost)
|
|
.unwrap_or_else(|e| e);
|
|
work_items.insert(insertion_index, (work, cost));
|
|
if !cgcx.opts.debugging_opts.no_parallel_llvm {
|
|
helper.request_token();
|
|
}
|
|
}
|
|
}
|
|
|
|
// In this branch, we know that everything has been codegened,
|
|
// so it's just a matter of determining whether the implicit
|
|
// Token is free to use for LLVM work.
|
|
match main_thread_worker_state {
|
|
MainThreadWorkerState::Idle => {
|
|
if let Some((item, _)) = work_items.pop() {
|
|
let cgcx = CodegenContext {
|
|
worker: get_worker_id(&mut free_worker_ids),
|
|
.. cgcx.clone()
|
|
};
|
|
maybe_start_llvm_timer(cgcx.config(item.module_kind()),
|
|
&mut llvm_start_time);
|
|
main_thread_worker_state = MainThreadWorkerState::LLVMing;
|
|
spawn_work(cgcx, item);
|
|
} else {
|
|
// There is no unstarted work, so let the main thread
|
|
// take over for a running worker. Otherwise the
|
|
// implicit token would just go to waste.
|
|
// We reduce the `running` counter by one. The
|
|
// `tokens.truncate()` below will take care of
|
|
// giving the Token back.
|
|
debug_assert!(running > 0);
|
|
running -= 1;
|
|
main_thread_worker_state = MainThreadWorkerState::LLVMing;
|
|
}
|
|
}
|
|
MainThreadWorkerState::Codegenning => {
|
|
bug!("codegen worker should not be codegenning after \
|
|
codegen was already completed")
|
|
}
|
|
MainThreadWorkerState::LLVMing => {
|
|
// Already making good use of that token
|
|
}
|
|
}
|
|
}
|
|
|
|
// Spin up what work we can, only doing this while we've got available
|
|
// parallelism slots and work left to spawn.
|
|
while !codegen_aborted && work_items.len() > 0 && running < tokens.len() {
|
|
let (item, _) = work_items.pop().unwrap();
|
|
|
|
maybe_start_llvm_timer(cgcx.config(item.module_kind()),
|
|
&mut llvm_start_time);
|
|
|
|
let cgcx = CodegenContext {
|
|
worker: get_worker_id(&mut free_worker_ids),
|
|
.. cgcx.clone()
|
|
};
|
|
|
|
spawn_work(cgcx, item);
|
|
running += 1;
|
|
}
|
|
|
|
// Relinquish accidentally acquired extra tokens
|
|
tokens.truncate(running);
|
|
|
|
// If a thread exits successfully then we drop a token associated
|
|
// with that worker and update our `running` count. We may later
|
|
// re-acquire a token to continue running more work. We may also not
|
|
// actually drop a token here if the worker was running with an
|
|
// "ephemeral token"
|
|
let mut free_worker = |worker_id| {
|
|
if main_thread_worker_state == MainThreadWorkerState::LLVMing {
|
|
main_thread_worker_state = MainThreadWorkerState::Idle;
|
|
} else {
|
|
running -= 1;
|
|
}
|
|
|
|
free_worker_ids.push(worker_id);
|
|
};
|
|
|
|
let msg = coordinator_receive.recv().unwrap();
|
|
match *msg.downcast::<Message<B>>().ok().unwrap() {
|
|
// Save the token locally and the next turn of the loop will use
|
|
// this to spawn a new unit of work, or it may get dropped
|
|
// immediately if we have no more work to spawn.
|
|
Message::Token(token) => {
|
|
match token {
|
|
Ok(token) => {
|
|
tokens.push(token);
|
|
|
|
if main_thread_worker_state == MainThreadWorkerState::LLVMing {
|
|
// If the main thread token is used for LLVM work
|
|
// at the moment, we turn that thread into a regular
|
|
// LLVM worker thread, so the main thread is free
|
|
// to react to codegen demand.
|
|
main_thread_worker_state = MainThreadWorkerState::Idle;
|
|
running += 1;
|
|
}
|
|
}
|
|
Err(e) => {
|
|
let msg = &format!("failed to acquire jobserver token: {}", e);
|
|
shared_emitter.fatal(msg);
|
|
// Exit the coordinator thread
|
|
panic!("{}", msg)
|
|
}
|
|
}
|
|
}
|
|
|
|
Message::CodegenDone { llvm_work_item, cost } => {
|
|
// We keep the queue sorted by estimated processing cost,
|
|
// so that more expensive items are processed earlier. This
|
|
// is good for throughput as it gives the main thread more
|
|
// time to fill up the queue and it avoids scheduling
|
|
// expensive items to the end.
|
|
// Note, however, that this is not ideal for memory
|
|
// consumption, as LLVM module sizes are not evenly
|
|
// distributed.
|
|
let insertion_index =
|
|
work_items.binary_search_by_key(&cost, |&(_, cost)| cost);
|
|
let insertion_index = match insertion_index {
|
|
Ok(idx) | Err(idx) => idx
|
|
};
|
|
work_items.insert(insertion_index, (llvm_work_item, cost));
|
|
|
|
if !cgcx.opts.debugging_opts.no_parallel_llvm {
|
|
helper.request_token();
|
|
}
|
|
assert!(!codegen_aborted);
|
|
assert_eq!(main_thread_worker_state,
|
|
MainThreadWorkerState::Codegenning);
|
|
main_thread_worker_state = MainThreadWorkerState::Idle;
|
|
}
|
|
|
|
Message::CodegenComplete => {
|
|
codegen_done = true;
|
|
assert!(!codegen_aborted);
|
|
assert_eq!(main_thread_worker_state,
|
|
MainThreadWorkerState::Codegenning);
|
|
main_thread_worker_state = MainThreadWorkerState::Idle;
|
|
}
|
|
|
|
// If codegen is aborted that means translation was aborted due
|
|
// to some normal-ish compiler error. In this situation we want
|
|
// to exit as soon as possible, but we want to make sure all
|
|
// existing work has finished. Flag codegen as being done, and
|
|
// then conditions above will ensure no more work is spawned but
|
|
// we'll keep executing this loop until `running` hits 0.
|
|
Message::CodegenAborted => {
|
|
assert!(!codegen_aborted);
|
|
codegen_done = true;
|
|
codegen_aborted = true;
|
|
assert_eq!(main_thread_worker_state,
|
|
MainThreadWorkerState::Codegenning);
|
|
}
|
|
Message::Done { result: Ok(compiled_module), worker_id } => {
|
|
free_worker(worker_id);
|
|
match compiled_module.kind {
|
|
ModuleKind::Regular => {
|
|
compiled_modules.push(compiled_module);
|
|
}
|
|
ModuleKind::Metadata => {
|
|
assert!(compiled_metadata_module.is_none());
|
|
compiled_metadata_module = Some(compiled_module);
|
|
}
|
|
ModuleKind::Allocator => {
|
|
assert!(compiled_allocator_module.is_none());
|
|
compiled_allocator_module = Some(compiled_module);
|
|
}
|
|
}
|
|
}
|
|
Message::NeedsFatLTO { result, worker_id } => {
|
|
assert!(!started_lto);
|
|
free_worker(worker_id);
|
|
needs_fat_lto.push(result);
|
|
}
|
|
Message::NeedsThinLTO { name, thin_buffer, worker_id } => {
|
|
assert!(!started_lto);
|
|
free_worker(worker_id);
|
|
needs_thin_lto.push((name, thin_buffer));
|
|
}
|
|
Message::AddImportOnlyModule { module_data, work_product } => {
|
|
assert!(!started_lto);
|
|
assert!(!codegen_done);
|
|
assert_eq!(main_thread_worker_state,
|
|
MainThreadWorkerState::Codegenning);
|
|
lto_import_only_modules.push((module_data, work_product));
|
|
main_thread_worker_state = MainThreadWorkerState::Idle;
|
|
}
|
|
// If the thread failed that means it panicked, so we abort immediately.
|
|
Message::Done { result: Err(()), worker_id: _ } => {
|
|
bug!("worker thread panicked");
|
|
}
|
|
Message::CodegenItem => {
|
|
bug!("the coordinator should not receive codegen requests")
|
|
}
|
|
}
|
|
}
|
|
|
|
if let Some(llvm_start_time) = llvm_start_time {
|
|
let total_llvm_time = Instant::now().duration_since(llvm_start_time);
|
|
// This is the top-level timing for all of LLVM, set the time-depth
|
|
// to zero.
|
|
set_time_depth(0);
|
|
print_time_passes_entry(cgcx.time_passes,
|
|
"LLVM passes",
|
|
total_llvm_time);
|
|
}
|
|
|
|
// Regardless of what order these modules completed in, report them to
|
|
// the backend in the same order every time to ensure that we're handing
|
|
// out deterministic results.
|
|
compiled_modules.sort_by(|a, b| a.name.cmp(&b.name));
|
|
|
|
let compiled_metadata_module = compiled_metadata_module
|
|
.expect("Metadata module not compiled?");
|
|
|
|
Ok(CompiledModules {
|
|
modules: compiled_modules,
|
|
metadata_module: compiled_metadata_module,
|
|
allocator_module: compiled_allocator_module,
|
|
})
|
|
});
|
|
|
|
// A heuristic that determines if we have enough LLVM WorkItems in the
|
|
// queue so that the main thread can do LLVM work instead of codegen
|
|
fn queue_full_enough(items_in_queue: usize,
|
|
workers_running: usize,
|
|
max_workers: usize) -> bool {
|
|
// Tune me, plz.
|
|
items_in_queue > 0 &&
|
|
items_in_queue >= max_workers.saturating_sub(workers_running / 2)
|
|
}
|
|
|
|
fn maybe_start_llvm_timer(config: &ModuleConfig,
|
|
llvm_start_time: &mut Option<Instant>) {
|
|
// We keep track of the -Ztime-passes output manually,
|
|
// since the closure-based interface does not fit well here.
|
|
if config.time_passes {
|
|
if llvm_start_time.is_none() {
|
|
*llvm_start_time = Some(Instant::now());
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
pub const CODEGEN_WORKER_ID: usize = ::std::usize::MAX;
|
|
pub const CODEGEN_WORKER_TIMELINE: time_graph::TimelineId =
|
|
time_graph::TimelineId(CODEGEN_WORKER_ID);
|
|
pub const CODEGEN_WORK_PACKAGE_KIND: time_graph::WorkPackageKind =
|
|
time_graph::WorkPackageKind(&["#DE9597", "#FED1D3", "#FDC5C7", "#B46668", "#88494B"]);
|
|
const LLVM_WORK_PACKAGE_KIND: time_graph::WorkPackageKind =
|
|
time_graph::WorkPackageKind(&["#7DB67A", "#C6EEC4", "#ACDAAA", "#579354", "#3E6F3C"]);
|
|
|
|
fn spawn_work<B: ExtraBackendMethods>(
|
|
cgcx: CodegenContext<B>,
|
|
work: WorkItem<B>
|
|
) {
|
|
let depth = time_depth();
|
|
|
|
thread::spawn(move || {
|
|
set_time_depth(depth);
|
|
|
|
// Set up a destructor which will fire off a message that we're done as
|
|
// we exit.
|
|
struct Bomb<B: ExtraBackendMethods> {
|
|
coordinator_send: Sender<Box<dyn Any + Send>>,
|
|
result: Option<WorkItemResult<B>>,
|
|
worker_id: usize,
|
|
}
|
|
impl<B: ExtraBackendMethods> Drop for Bomb<B> {
|
|
fn drop(&mut self) {
|
|
let worker_id = self.worker_id;
|
|
let msg = match self.result.take() {
|
|
Some(WorkItemResult::Compiled(m)) => {
|
|
Message::Done::<B> { result: Ok(m), worker_id }
|
|
}
|
|
Some(WorkItemResult::NeedsFatLTO(m)) => {
|
|
Message::NeedsFatLTO::<B> { result: m, worker_id }
|
|
}
|
|
Some(WorkItemResult::NeedsThinLTO(name, thin_buffer)) => {
|
|
Message::NeedsThinLTO::<B> { name, thin_buffer, worker_id }
|
|
}
|
|
None => Message::Done::<B> { result: Err(()), worker_id }
|
|
};
|
|
drop(self.coordinator_send.send(Box::new(msg)));
|
|
}
|
|
}
|
|
|
|
let mut bomb = Bomb::<B> {
|
|
coordinator_send: cgcx.coordinator_send.clone(),
|
|
result: None,
|
|
worker_id: cgcx.worker,
|
|
};
|
|
|
|
// Execute the work itself, and if it finishes successfully then flag
|
|
// ourselves as a success as well.
|
|
//
|
|
// Note that we ignore any `FatalError` coming out of `execute_work_item`,
|
|
// as a diagnostic was already sent off to the main thread - just
|
|
// surface that there was an error in this worker.
|
|
bomb.result = {
|
|
let timeline = cgcx.time_graph.as_ref().map(|tg| {
|
|
tg.start(time_graph::TimelineId(cgcx.worker),
|
|
LLVM_WORK_PACKAGE_KIND,
|
|
&work.name())
|
|
});
|
|
let mut timeline = timeline.unwrap_or(Timeline::noop());
|
|
execute_work_item(&cgcx, work, &mut timeline).ok()
|
|
};
|
|
});
|
|
}
|
|
|
|
pub fn run_assembler<B: ExtraBackendMethods>(
|
|
cgcx: &CodegenContext<B>,
|
|
handler: &Handler,
|
|
assembly: &Path,
|
|
object: &Path
|
|
) {
|
|
let assembler = cgcx.assembler_cmd
|
|
.as_ref()
|
|
.expect("cgcx.assembler_cmd is missing?");
|
|
|
|
let pname = &assembler.name;
|
|
let mut cmd = assembler.cmd.clone();
|
|
cmd.arg("-c").arg("-o").arg(object).arg(assembly);
|
|
debug!("{:?}", cmd);
|
|
|
|
match cmd.output() {
|
|
Ok(prog) => {
|
|
if !prog.status.success() {
|
|
let mut note = prog.stderr.clone();
|
|
note.extend_from_slice(&prog.stdout);
|
|
|
|
handler.struct_err(&format!("linking with `{}` failed: {}",
|
|
pname.display(),
|
|
prog.status))
|
|
.note(&format!("{:?}", &cmd))
|
|
.note(str::from_utf8(¬e[..]).unwrap())
|
|
.emit();
|
|
handler.abort_if_errors();
|
|
}
|
|
},
|
|
Err(e) => {
|
|
handler.err(&format!("could not exec the linker `{}`: {}", pname.display(), e));
|
|
handler.abort_if_errors();
|
|
}
|
|
}
|
|
}
|
|
|
|
|
|
enum SharedEmitterMessage {
|
|
Diagnostic(Diagnostic),
|
|
InlineAsmError(u32, String),
|
|
AbortIfErrors,
|
|
Fatal(String),
|
|
}
|
|
|
|
#[derive(Clone)]
|
|
pub struct SharedEmitter {
|
|
sender: Sender<SharedEmitterMessage>,
|
|
}
|
|
|
|
pub struct SharedEmitterMain {
|
|
receiver: Receiver<SharedEmitterMessage>,
|
|
}
|
|
|
|
impl SharedEmitter {
|
|
pub fn new() -> (SharedEmitter, SharedEmitterMain) {
|
|
let (sender, receiver) = channel();
|
|
|
|
(SharedEmitter { sender }, SharedEmitterMain { receiver })
|
|
}
|
|
|
|
pub fn inline_asm_error(&self, cookie: u32, msg: String) {
|
|
drop(self.sender.send(SharedEmitterMessage::InlineAsmError(cookie, msg)));
|
|
}
|
|
|
|
pub fn fatal(&self, msg: &str) {
|
|
drop(self.sender.send(SharedEmitterMessage::Fatal(msg.to_string())));
|
|
}
|
|
}
|
|
|
|
impl Emitter for SharedEmitter {
|
|
fn emit(&mut self, db: &DiagnosticBuilder) {
|
|
drop(self.sender.send(SharedEmitterMessage::Diagnostic(Diagnostic {
|
|
msg: db.message(),
|
|
code: db.code.clone(),
|
|
lvl: db.level,
|
|
})));
|
|
for child in &db.children {
|
|
drop(self.sender.send(SharedEmitterMessage::Diagnostic(Diagnostic {
|
|
msg: child.message(),
|
|
code: None,
|
|
lvl: child.level,
|
|
})));
|
|
}
|
|
drop(self.sender.send(SharedEmitterMessage::AbortIfErrors));
|
|
}
|
|
}
|
|
|
|
impl SharedEmitterMain {
|
|
pub fn check(&self, sess: &Session, blocking: bool) {
|
|
loop {
|
|
let message = if blocking {
|
|
match self.receiver.recv() {
|
|
Ok(message) => Ok(message),
|
|
Err(_) => Err(()),
|
|
}
|
|
} else {
|
|
match self.receiver.try_recv() {
|
|
Ok(message) => Ok(message),
|
|
Err(_) => Err(()),
|
|
}
|
|
};
|
|
|
|
match message {
|
|
Ok(SharedEmitterMessage::Diagnostic(diag)) => {
|
|
let handler = sess.diagnostic();
|
|
match diag.code {
|
|
Some(ref code) => {
|
|
handler.emit_with_code(&MultiSpan::new(),
|
|
&diag.msg,
|
|
code.clone(),
|
|
diag.lvl);
|
|
}
|
|
None => {
|
|
handler.emit(&MultiSpan::new(),
|
|
&diag.msg,
|
|
diag.lvl);
|
|
}
|
|
}
|
|
}
|
|
Ok(SharedEmitterMessage::InlineAsmError(cookie, msg)) => {
|
|
match Mark::from_u32(cookie).expn_info() {
|
|
Some(ei) => sess.span_err(ei.call_site, &msg),
|
|
None => sess.err(&msg),
|
|
}
|
|
}
|
|
Ok(SharedEmitterMessage::AbortIfErrors) => {
|
|
sess.abort_if_errors();
|
|
}
|
|
Ok(SharedEmitterMessage::Fatal(msg)) => {
|
|
sess.fatal(&msg);
|
|
}
|
|
Err(_) => {
|
|
break;
|
|
}
|
|
}
|
|
|
|
}
|
|
}
|
|
}
|
|
|
|
pub struct OngoingCodegen<B: ExtraBackendMethods> {
|
|
pub backend: B,
|
|
pub crate_name: Symbol,
|
|
pub crate_hash: Svh,
|
|
pub metadata: EncodedMetadata,
|
|
pub windows_subsystem: Option<String>,
|
|
pub linker_info: LinkerInfo,
|
|
pub crate_info: CrateInfo,
|
|
pub time_graph: Option<TimeGraph>,
|
|
pub coordinator_send: Sender<Box<dyn Any + Send>>,
|
|
pub codegen_worker_receive: Receiver<Message<B>>,
|
|
pub shared_emitter_main: SharedEmitterMain,
|
|
pub future: thread::JoinHandle<Result<CompiledModules, ()>>,
|
|
pub output_filenames: Arc<OutputFilenames>,
|
|
}
|
|
|
|
impl<B: ExtraBackendMethods> OngoingCodegen<B> {
|
|
pub fn join(
|
|
self,
|
|
sess: &Session
|
|
) -> (CodegenResults, FxHashMap<WorkProductId, WorkProduct>) {
|
|
self.shared_emitter_main.check(sess, true);
|
|
let compiled_modules = match self.future.join() {
|
|
Ok(Ok(compiled_modules)) => compiled_modules,
|
|
Ok(Err(())) => {
|
|
sess.abort_if_errors();
|
|
panic!("expected abort due to worker thread errors")
|
|
},
|
|
Err(_) => {
|
|
bug!("panic during codegen/LLVM phase");
|
|
}
|
|
};
|
|
|
|
sess.cgu_reuse_tracker.check_expected_reuse(sess);
|
|
|
|
sess.abort_if_errors();
|
|
|
|
if let Some(time_graph) = self.time_graph {
|
|
time_graph.dump(&format!("{}-timings", self.crate_name));
|
|
}
|
|
|
|
let work_products =
|
|
copy_all_cgu_workproducts_to_incr_comp_cache_dir(sess,
|
|
&compiled_modules);
|
|
produce_final_output_artifacts(sess,
|
|
&compiled_modules,
|
|
&self.output_filenames);
|
|
|
|
// FIXME: time_llvm_passes support - does this use a global context or
|
|
// something?
|
|
if sess.codegen_units() == 1 && sess.time_llvm_passes() {
|
|
self.backend.print_pass_timings()
|
|
}
|
|
|
|
(CodegenResults {
|
|
crate_name: self.crate_name,
|
|
crate_hash: self.crate_hash,
|
|
metadata: self.metadata,
|
|
windows_subsystem: self.windows_subsystem,
|
|
linker_info: self.linker_info,
|
|
crate_info: self.crate_info,
|
|
|
|
modules: compiled_modules.modules,
|
|
allocator_module: compiled_modules.allocator_module,
|
|
metadata_module: compiled_modules.metadata_module,
|
|
}, work_products)
|
|
}
|
|
|
|
pub fn submit_pre_codegened_module_to_llvm(&self,
|
|
tcx: TyCtxt,
|
|
module: ModuleCodegen<B::Module>) {
|
|
self.wait_for_signal_to_codegen_item();
|
|
self.check_for_errors(tcx.sess);
|
|
|
|
// These are generally cheap and won't through off scheduling.
|
|
let cost = 0;
|
|
submit_codegened_module_to_llvm(&self.backend, tcx, module, cost);
|
|
}
|
|
|
|
pub fn codegen_finished(&self, tcx: TyCtxt) {
|
|
self.wait_for_signal_to_codegen_item();
|
|
self.check_for_errors(tcx.sess);
|
|
drop(self.coordinator_send.send(Box::new(Message::CodegenComplete::<B>)));
|
|
}
|
|
|
|
/// Consumes this context indicating that codegen was entirely aborted, and
|
|
/// we need to exit as quickly as possible.
|
|
///
|
|
/// This method blocks the current thread until all worker threads have
|
|
/// finished, and all worker threads should have exited or be real close to
|
|
/// exiting at this point.
|
|
pub fn codegen_aborted(self) {
|
|
// Signal to the coordinator it should spawn no more work and start
|
|
// shutdown.
|
|
drop(self.coordinator_send.send(Box::new(Message::CodegenAborted::<B>)));
|
|
drop(self.future.join());
|
|
}
|
|
|
|
pub fn check_for_errors(&self, sess: &Session) {
|
|
self.shared_emitter_main.check(sess, false);
|
|
}
|
|
|
|
pub fn wait_for_signal_to_codegen_item(&self) {
|
|
match self.codegen_worker_receive.recv() {
|
|
Ok(Message::CodegenItem) => {
|
|
// Nothing to do
|
|
}
|
|
Ok(_) => panic!("unexpected message"),
|
|
Err(_) => {
|
|
// One of the LLVM threads must have panicked, fall through so
|
|
// error handling can be reached.
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
pub fn submit_codegened_module_to_llvm<B: ExtraBackendMethods>(
|
|
_backend: &B,
|
|
tcx: TyCtxt,
|
|
module: ModuleCodegen<B::Module>,
|
|
cost: u64
|
|
) {
|
|
let llvm_work_item = WorkItem::Optimize(module);
|
|
drop(tcx.tx_to_llvm_workers.lock().send(Box::new(Message::CodegenDone::<B> {
|
|
llvm_work_item,
|
|
cost,
|
|
})));
|
|
}
|
|
|
|
pub fn submit_post_lto_module_to_llvm<B: ExtraBackendMethods>(
|
|
_backend: &B,
|
|
tcx: TyCtxt,
|
|
module: CachedModuleCodegen
|
|
) {
|
|
let llvm_work_item = WorkItem::CopyPostLtoArtifacts(module);
|
|
drop(tcx.tx_to_llvm_workers.lock().send(Box::new(Message::CodegenDone::<B> {
|
|
llvm_work_item,
|
|
cost: 0,
|
|
})));
|
|
}
|
|
|
|
pub fn submit_pre_lto_module_to_llvm<B: ExtraBackendMethods>(
|
|
_backend: &B,
|
|
tcx: TyCtxt,
|
|
module: CachedModuleCodegen
|
|
) {
|
|
let filename = pre_lto_bitcode_filename(&module.name);
|
|
let bc_path = in_incr_comp_dir_sess(tcx.sess, &filename);
|
|
let file = fs::File::open(&bc_path).unwrap_or_else(|e| {
|
|
panic!("failed to open bitcode file `{}`: {}", bc_path.display(), e)
|
|
});
|
|
|
|
let mmap = unsafe {
|
|
memmap::Mmap::map(&file).unwrap_or_else(|e| {
|
|
panic!("failed to mmap bitcode file `{}`: {}", bc_path.display(), e)
|
|
})
|
|
};
|
|
// Schedule the module to be loaded
|
|
drop(tcx.tx_to_llvm_workers.lock().send(Box::new(Message::AddImportOnlyModule::<B> {
|
|
module_data: SerializedModule::FromUncompressedFile(mmap),
|
|
work_product: module.source,
|
|
})));
|
|
}
|
|
|
|
pub fn pre_lto_bitcode_filename(module_name: &str) -> String {
|
|
format!("{}.{}", module_name, PRE_THIN_LTO_BC_EXT)
|
|
}
|
|
|
|
fn msvc_imps_needed(tcx: TyCtxt) -> bool {
|
|
// This should never be true (because it's not supported). If it is true,
|
|
// something is wrong with commandline arg validation.
|
|
assert!(!(tcx.sess.opts.cg.linker_plugin_lto.enabled() &&
|
|
tcx.sess.target.target.options.is_like_msvc &&
|
|
tcx.sess.opts.cg.prefer_dynamic));
|
|
|
|
tcx.sess.target.target.options.is_like_msvc &&
|
|
tcx.sess.crate_types.borrow().iter().any(|ct| *ct == config::CrateType::Rlib) &&
|
|
// ThinLTO can't handle this workaround in all cases, so we don't
|
|
// emit the `__imp_` symbols. Instead we make them unnecessary by disallowing
|
|
// dynamic linking when linker plugin LTO is enabled.
|
|
!tcx.sess.opts.cg.linker_plugin_lto.enabled()
|
|
}
|