Pass target_cpu to LinkerInfo::new instead of link_binary

This is one step towards separating the linking code from codegen backends

Author: bjorn3

compiler/rustc_codegen_cranelift/src/driver/aot.rs

@@ -295,7 +295,7 @@ pub(super) fn run_aot(
             metadata_module,
             metadata,
             windows_subsystem,
-            linker_info: LinkerInfo::new(tcx),
+            linker_info: LinkerInfo::new(tcx, crate::target_triple(tcx.sess).to_string()),
             crate_info: CrateInfo::new(tcx),
         },
         work_products,

compiler/rustc_codegen_cranelift/src/lib.rs

@@ -267,13 +267,11 @@ impl CodegenBackend for CraneliftCodegenBackend {
     ) -> Result<(), ErrorReported> {
         use rustc_codegen_ssa::back::link::link_binary;
 
-        let target_cpu = crate::target_triple(sess).to_string();
         link_binary::<crate::archive::ArArchiveBuilder<'_>>(
             sess,
             &codegen_results,
             outputs,
             &codegen_results.crate_name.as_str(),
-            &target_cpu,
         );
 
         Ok(())

compiler/rustc_codegen_llvm/src/lib.rs

@@ -270,6 +270,7 @@ impl CodegenBackend for LlvmCodegenBackend {
         Box::new(rustc_codegen_ssa::base::codegen_crate(
             LlvmCodegenBackend(()),
             tcx,
+            crate::llvm_util::target_cpu(tcx.sess).to_string(),
             metadata,
             need_metadata_module,
         ))
@@ -305,13 +306,11 @@ impl CodegenBackend for LlvmCodegenBackend {
 
         // Run the linker on any artifacts that resulted from the LLVM run.
         // This should produce either a finished executable or library.
-        let target_cpu = crate::llvm_util::target_cpu(sess);
         link_binary::<LlvmArchiveBuilder<'_>>(
             sess,
             &codegen_results,
             outputs,
             &codegen_results.crate_name.as_str(),
-            target_cpu,
         );
 
         Ok(())

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -50,7 +50,6 @@ pub fn link_binary<'a, B: ArchiveBuilder<'a>>(
     codegen_results: &CodegenResults,
     outputs: &OutputFilenames,
     crate_name: &str,
-    target_cpu: &str,
 ) {
     let _timer = sess.timer("link_binary");
     let output_metadata = sess.opts.output_types.contains_key(&OutputType::Metadata);
@@ -100,7 +99,6 @@ pub fn link_binary<'a, B: ArchiveBuilder<'a>>(
                         &out_filename,
                         codegen_results,
                         path.as_ref(),
-                        target_cpu,
                     );
                 }
             }
@@ -531,7 +529,6 @@ fn link_natively<'a, B: ArchiveBuilder<'a>>(
     out_filename: &Path,
     codegen_results: &CodegenResults,
     tmpdir: &Path,
-    target_cpu: &str,
 ) {
     info!("preparing {:?} to {:?}", crate_type, out_filename);
     let (linker_path, flavor) = linker_and_flavor(sess);
@@ -543,7 +540,6 @@ fn link_natively<'a, B: ArchiveBuilder<'a>>(
         tmpdir,
         out_filename,
         codegen_results,
-        target_cpu,
     );
 
     linker::disable_localization(&mut cmd);
@@ -1617,14 +1613,13 @@ fn linker_with_args<'a, B: ArchiveBuilder<'a>>(
     tmpdir: &Path,
     out_filename: &Path,
     codegen_results: &CodegenResults,
-    target_cpu: &str,
 ) -> Command {
     let crt_objects_fallback = crt_objects_fallback(sess, crate_type);
     let base_cmd = get_linker(sess, path, flavor, crt_objects_fallback);
     // FIXME: Move `/LIBPATH` addition for uwp targets from the linker construction
     // to the linker args construction.
     assert!(base_cmd.get_args().is_empty() || sess.target.vendor == "uwp");
-    let cmd = &mut *codegen_results.linker_info.to_linker(base_cmd, &sess, flavor, target_cpu);
+    let cmd = &mut *codegen_results.linker_info.to_linker(base_cmd, &sess, flavor);
     let link_output_kind = link_output_kind(sess, crate_type);
 
     // NO-OPT-OUT, OBJECT-FILES-MAYBE, CUSTOMIZATION-POINT

compiler/rustc_codegen_ssa/src/back/linker.rs

@@ -37,12 +37,14 @@ pub fn disable_localization(linker: &mut Command) {
 /// need out of the shared crate context before we get rid of it.
 #[derive(Encodable, Decodable)]
 pub struct LinkerInfo {
+    target_cpu: String,
     exports: FxHashMap<CrateType, Vec<String>>,
 }
 
 impl LinkerInfo {
-    pub fn new(tcx: TyCtxt<'_>) -> LinkerInfo {
+    pub fn new(tcx: TyCtxt<'_>, target_cpu: String) -> LinkerInfo {
         LinkerInfo {
+            target_cpu,
             exports: tcx
                 .sess
                 .crate_types()
@@ -57,38 +59,31 @@ impl LinkerInfo {
         cmd: Command,
         sess: &'a Session,
         flavor: LinkerFlavor,
-        target_cpu: &'a str,
     ) -> Box<dyn Linker + 'a> {
         match flavor {
             LinkerFlavor::Lld(LldFlavor::Link) | LinkerFlavor::Msvc => {
                 Box::new(MsvcLinker { cmd, sess, info: self }) as Box<dyn Linker>
             }
             LinkerFlavor::Em => Box::new(EmLinker { cmd, sess, info: self }) as Box<dyn Linker>,
-            LinkerFlavor::Gcc => Box::new(GccLinker {
-                cmd,
-                sess,
-                info: self,
-                hinted_static: false,
-                is_ld: false,
-                target_cpu,
-            }) as Box<dyn Linker>,
+            LinkerFlavor::Gcc => {
+                Box::new(GccLinker { cmd, sess, info: self, hinted_static: false, is_ld: false })
+                    as Box<dyn Linker>
+            }
 
             LinkerFlavor::Lld(LldFlavor::Ld)
             | LinkerFlavor::Lld(LldFlavor::Ld64)
-            | LinkerFlavor::Ld => Box::new(GccLinker {
-                cmd,
-                sess,
-                info: self,
-                hinted_static: false,
-                is_ld: true,
-                target_cpu,
-            }) as Box<dyn Linker>,
+            | LinkerFlavor::Ld => {
+                Box::new(GccLinker { cmd, sess, info: self, hinted_static: false, is_ld: true })
+                    as Box<dyn Linker>
+            }
 
             LinkerFlavor::Lld(LldFlavor::Wasm) => {
                 Box::new(WasmLd::new(cmd, sess, self)) as Box<dyn Linker>
             }
 
-            LinkerFlavor::PtxLinker => Box::new(PtxLinker { cmd, sess }) as Box<dyn Linker>,
+            LinkerFlavor::PtxLinker => {
+                Box::new(PtxLinker { cmd, sess, info: self }) as Box<dyn Linker>
+            }
         }
     }
 }
@@ -156,7 +151,6 @@ pub struct GccLinker<'a> {
     hinted_static: bool, // Keeps track of the current hinting mode.
     // Link as ld
     is_ld: bool,
-    target_cpu: &'a str,
 }
 
 impl<'a> GccLinker<'a> {
@@ -228,8 +222,7 @@ impl<'a> GccLinker<'a> {
         };
 
         self.linker_arg(&format!("-plugin-opt={}", opt_level));
-        let target_cpu = self.target_cpu;
-        self.linker_arg(&format!("-plugin-opt=mcpu={}", target_cpu));
+        self.linker_arg(&format!("-plugin-opt=mcpu={}", self.info.target_cpu));
     }
 
     fn build_dylib(&mut self, out_filename: &Path) {
@@ -1276,6 +1269,7 @@ fn exported_symbols(tcx: TyCtxt<'_>, crate_type: CrateType) -> Vec<String> {
 pub struct PtxLinker<'a> {
     cmd: Command,
     sess: &'a Session,
+    info: &'a LinkerInfo,
 }
 
 impl<'a> Linker for PtxLinker<'a> {
@@ -1321,10 +1315,7 @@ impl<'a> Linker for PtxLinker<'a> {
 
     fn finalize(&mut self) {
         // Provide the linker with fallback to internal `target-cpu`.
-        self.cmd.arg("--fallback-arch").arg(match self.sess.opts.cg.target_cpu {
-            Some(ref s) => s,
-            None => &self.sess.target.cpu,
-        });
+        self.cmd.arg("--fallback-arch").arg(&self.info.target_cpu);
     }
 
     fn link_dylib(&mut self, _lib: Symbol) {

compiler/rustc_codegen_ssa/src/back/write.rs

@@ -426,6 +426,7 @@ fn need_pre_lto_bitcode_for_incr_comp(sess: &Session) -> bool {
 pub fn start_async_codegen<B: ExtraBackendMethods>(
     backend: B,
     tcx: TyCtxt<'_>,
+    target_cpu: String,
     metadata: EncodedMetadata,
     total_cgus: usize,
 ) -> OngoingCodegen<B> {
@@ -448,7 +449,7 @@ pub fn start_async_codegen<B: ExtraBackendMethods>(
         subsystem.to_string()
     });
 
-    let linker_info = LinkerInfo::new(tcx);
+    let linker_info = LinkerInfo::new(tcx, target_cpu);
     let crate_info = CrateInfo::new(tcx);
 
     let regular_config =

compiler/rustc_codegen_ssa/src/base.rs

@@ -461,12 +461,13 @@ fn get_argc_argv<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
 pub fn codegen_crate<B: ExtraBackendMethods>(
     backend: B,
     tcx: TyCtxt<'tcx>,
+    target_cpu: String,
     metadata: EncodedMetadata,
     need_metadata_module: bool,
 ) -> OngoingCodegen<B> {
     // Skip crate items and just output metadata in -Z no-codegen mode.
     if tcx.sess.opts.debugging_opts.no_codegen || !tcx.sess.opts.output_types.should_codegen() {
-        let ongoing_codegen = start_async_codegen(backend, tcx, metadata, 1);
+        let ongoing_codegen = start_async_codegen(backend, tcx, target_cpu, metadata, 1);
 
         ongoing_codegen.codegen_finished(tcx);
 
@@ -492,7 +493,8 @@ pub fn codegen_crate<B: ExtraBackendMethods>(
         }
     }
 
-    let ongoing_codegen = start_async_codegen(backend.clone(), tcx, metadata, codegen_units.len());
+    let ongoing_codegen =
+        start_async_codegen(backend.clone(), tcx, target_cpu, metadata, codegen_units.len());
     let ongoing_codegen = AbortCodegenOnDrop::<B>(Some(ongoing_codegen));
 
     // Codegen an allocator shim, if necessary.