Rollup merge of #149209 - lto_refactors8, r=jackh726

Move LTO to OngoingCodegen::join

This will make it easier to in the future move all this code to link_binary.

Follow up to rust-lang/rust#147810
Part of rust-lang/compiler-team#908

Author: jhpratt

src/back/lto.rs

@@ -26,11 +26,11 @@ use std::sync::atomic::Ordering;
 use gccjit::{Context, OutputKind};
 use object::read::archive::ArchiveFile;
 use rustc_codegen_ssa::back::lto::{SerializedModule, ThinModule, ThinShared};
-use rustc_codegen_ssa::back::write::{CodegenContext, FatLtoInput};
+use rustc_codegen_ssa::back::write::{CodegenContext, FatLtoInput, SharedEmitter};
 use rustc_codegen_ssa::traits::*;
 use rustc_codegen_ssa::{ModuleCodegen, ModuleKind, looks_like_rust_object_file};
 use rustc_data_structures::memmap::Mmap;
-use rustc_errors::DiagCtxtHandle;
+use rustc_errors::{DiagCtxt, DiagCtxtHandle};
 use rustc_log::tracing::info;
 use rustc_middle::bug;
 use rustc_middle::dep_graph::WorkProduct;
@@ -112,10 +112,11 @@ fn save_as_file(obj: &[u8], path: &Path) -> Result<(), LtoBitcodeFromRlib> {
 /// for further optimization.
 pub(crate) fn run_fat(
     cgcx: &CodegenContext<GccCodegenBackend>,
+    shared_emitter: &SharedEmitter,
     each_linked_rlib_for_lto: &[PathBuf],
     modules: Vec<FatLtoInput<GccCodegenBackend>>,
 ) -> ModuleCodegen<GccContext> {
-    let dcx = cgcx.create_dcx();
+    let dcx = DiagCtxt::new(Box::new(shared_emitter.clone()));
     let dcx = dcx.handle();
     let lto_data = prepare_lto(cgcx, each_linked_rlib_for_lto, dcx);
     /*let symbols_below_threshold =
@@ -283,14 +284,13 @@ impl ModuleBufferMethods for ModuleBuffer {
 /// can simply be copied over from the incr. comp. cache.
 pub(crate) fn run_thin(
     cgcx: &CodegenContext<GccCodegenBackend>,
+    dcx: DiagCtxtHandle<'_>,
     each_linked_rlib_for_lto: &[PathBuf],
     modules: Vec<(String, ThinBuffer)>,
     cached_modules: Vec<(SerializedModule<ModuleBuffer>, WorkProduct)>,
 ) -> (Vec<ThinModule<GccCodegenBackend>>, Vec<WorkProduct>) {
-    let dcx = cgcx.create_dcx();
-    let dcx = dcx.handle();
     let lto_data = prepare_lto(cgcx, each_linked_rlib_for_lto, dcx);
-    if cgcx.opts.cg.linker_plugin_lto.enabled() {
+    if cgcx.use_linker_plugin_lto {
         unreachable!(
             "We should never reach this case if the LTO step \
                       is deferred to the linker"
@@ -522,8 +522,6 @@ pub fn optimize_thin_module(
     thin_module: ThinModule<GccCodegenBackend>,
     _cgcx: &CodegenContext<GccCodegenBackend>,
 ) -> ModuleCodegen<GccContext> {
-    //let dcx = cgcx.create_dcx();
-
     //let module_name = &thin_module.shared.module_names[thin_module.idx];
     /*let tm_factory_config = TargetMachineFactoryConfig::new(cgcx, module_name.to_str().unwrap());
     let tm = (cgcx.tm_factory)(tm_factory_config).map_err(|e| write::llvm_err(&dcx, e))?;*/

src/back/write.rs

@@ -2,8 +2,11 @@ use std::{env, fs};
 
 use gccjit::{Context, OutputKind};
 use rustc_codegen_ssa::back::link::ensure_removed;
-use rustc_codegen_ssa::back::write::{BitcodeSection, CodegenContext, EmitObj, ModuleConfig};
+use rustc_codegen_ssa::back::write::{
+    BitcodeSection, CodegenContext, EmitObj, ModuleConfig, SharedEmitter,
+};
 use rustc_codegen_ssa::{CompiledModule, ModuleCodegen};
+use rustc_errors::DiagCtxt;
 use rustc_fs_util::link_or_copy;
 use rustc_log::tracing::debug;
 use rustc_session::config::OutputType;
@@ -15,10 +18,11 @@ use crate::{GccCodegenBackend, GccContext, LtoMode};
 
 pub(crate) fn codegen(
     cgcx: &CodegenContext<GccCodegenBackend>,
+    shared_emitter: &SharedEmitter,
     module: ModuleCodegen<GccContext>,
     config: &ModuleConfig,
 ) -> CompiledModule {
-    let dcx = cgcx.create_dcx();
+    let dcx = DiagCtxt::new(Box::new(shared_emitter.clone()));
     let dcx = dcx.handle();
 
     let _timer = cgcx.prof.generic_activity_with_arg("GCC_module_codegen", &*module.name);

src/lib.rs

@@ -84,7 +84,7 @@ use gccjit::{TargetInfo, Version};
 use rustc_ast::expand::allocator::AllocatorMethod;
 use rustc_codegen_ssa::back::lto::{SerializedModule, ThinModule};
 use rustc_codegen_ssa::back::write::{
-    CodegenContext, FatLtoInput, ModuleConfig, TargetMachineFactoryFn,
+    CodegenContext, FatLtoInput, ModuleConfig, SharedEmitter, TargetMachineFactoryFn,
 };
 use rustc_codegen_ssa::base::codegen_crate;
 use rustc_codegen_ssa::target_features::cfg_target_feature;
@@ -435,23 +435,25 @@ impl WriteBackendMethods for GccCodegenBackend {
 
     fn run_and_optimize_fat_lto(
         cgcx: &CodegenContext<Self>,
+        shared_emitter: &SharedEmitter,
         // FIXME(bjorn3): Limit LTO exports to these symbols
         _exported_symbols_for_lto: &[String],
         each_linked_rlib_for_lto: &[PathBuf],
         modules: Vec<FatLtoInput<Self>>,
     ) -> ModuleCodegen<Self::Module> {
-        back::lto::run_fat(cgcx, each_linked_rlib_for_lto, modules)
+        back::lto::run_fat(cgcx, shared_emitter, each_linked_rlib_for_lto, modules)
     }
 
     fn run_thin_lto(
         cgcx: &CodegenContext<Self>,
+        dcx: DiagCtxtHandle<'_>,
         // FIXME(bjorn3): Limit LTO exports to these symbols
         _exported_symbols_for_lto: &[String],
         each_linked_rlib_for_lto: &[PathBuf],
         modules: Vec<(String, Self::ThinBuffer)>,
         cached_modules: Vec<(SerializedModule<Self::ModuleBuffer>, WorkProduct)>,
     ) -> (Vec<ThinModule<Self>>, Vec<WorkProduct>) {
-        back::lto::run_thin(cgcx, each_linked_rlib_for_lto, modules, cached_modules)
+        back::lto::run_thin(cgcx, dcx, each_linked_rlib_for_lto, modules, cached_modules)
     }
 
     fn print_pass_timings(&self) {
@@ -464,7 +466,7 @@ impl WriteBackendMethods for GccCodegenBackend {
 
     fn optimize(
         _cgcx: &CodegenContext<Self>,
-        _dcx: DiagCtxtHandle<'_>,
+        _shared_emitter: &SharedEmitter,
         module: &mut ModuleCodegen<Self::Module>,
         config: &ModuleConfig,
     ) {
@@ -473,17 +475,19 @@ impl WriteBackendMethods for GccCodegenBackend {
 
     fn optimize_thin(
         cgcx: &CodegenContext<Self>,
+        _shared_emitter: &SharedEmitter,
         thin: ThinModule<Self>,
     ) -> ModuleCodegen<Self::Module> {
         back::lto::optimize_thin_module(thin, cgcx)
     }
 
     fn codegen(
         cgcx: &CodegenContext<Self>,
+        shared_emitter: &SharedEmitter,
         module: ModuleCodegen<Self::Module>,
         config: &ModuleConfig,
     ) -> CompiledModule {
-        back::write::codegen(cgcx, module, config)
+        back::write::codegen(cgcx, shared_emitter, module, config)
     }
 
     fn prepare_thin(module: ModuleCodegen<Self::Module>) -> (String, Self::ThinBuffer) {