Simplify LLVM bitcode linker in bootstrap and add tests for it

src/bootstrap/src/core/build_steps/compile.rs

@@ -2059,14 +2059,20 @@ impl Step for Assemble {
                 trace!("llvm-bitcode-linker enabled, installing");
                 let llvm_bitcode_linker =
                     builder.ensure(crate::core::build_steps::tool::LlvmBitcodeLinker {
-                        compiler,
+                        build_compiler: compiler,
                         target: target_compiler.host,
-                        extra_features: vec![],
                     });
+
+                // Copy the llvm-bitcode-linker to the self-contained binary directory
+                let bindir_self_contained = builder
+                    .sysroot(compiler)
+                    .join(format!("lib/rustlib/{}/bin/self-contained", compiler.host));
                 let tool_exe = exe("llvm-bitcode-linker", target_compiler.host);
+
+                t!(fs::create_dir_all(&bindir_self_contained));
                 builder.copy_link(
                     &llvm_bitcode_linker.tool_path,
-                    &libdir_bin.join(tool_exe),
+                    &bindir_self_contained.join(tool_exe),
                     FileType::Executable,
                 );
             }

src/bootstrap/src/core/build_steps/dist.rs

@@ -2375,7 +2375,7 @@ impl Step for LlvmBitcodeLinker {
         builder.ensure(compile::Rustc::new(compiler, target));
 
         let llbc_linker =
-            builder.ensure(tool::LlvmBitcodeLinker { compiler, target, extra_features: vec![] });
+            builder.ensure(tool::LlvmBitcodeLinker { build_compiler: compiler, target });
 
         let self_contained_bin_dir = format!("lib/rustlib/{}/bin/self-contained", target.triple);
 

src/bootstrap/src/core/build_steps/tool.rs

@@ -910,6 +910,13 @@ impl Step for LldWrapper {
 
         tool_result
     }
+
+    fn metadata(&self) -> Option<StepMetadata> {
+        Some(
+            StepMetadata::build("LldWrapper", self.target_compiler.host)
+                .built_by(self.build_compiler),
+        )
+    }
 }
 
 #[derive(Debug, Clone, Hash, PartialEq, Eq)]
@@ -1014,9 +1021,8 @@ impl Step for RustAnalyzerProcMacroSrv {
 
 #[derive(Debug, Clone, Hash, PartialEq, Eq)]
 pub struct LlvmBitcodeLinker {
-    pub compiler: Compiler,
+    pub build_compiler: Compiler,
     pub target: TargetSelection,
-    pub extra_features: Vec<String>,
 }
 
 impl Step for LlvmBitcodeLinker {
@@ -1032,8 +1038,9 @@ impl Step for LlvmBitcodeLinker {
 
     fn make_run(run: RunConfig<'_>) {
         run.builder.ensure(LlvmBitcodeLinker {
-            compiler: run.builder.compiler(run.builder.top_stage, run.builder.config.host_target),
-            extra_features: Vec::new(),
+            build_compiler: run
+                .builder
+                .compiler(run.builder.top_stage, run.builder.config.host_target),
             target: run.target,
         });
     }
@@ -1043,35 +1050,22 @@ impl Step for LlvmBitcodeLinker {
         instrument(level = "debug", name = "LlvmBitcodeLinker::run", skip_all)
     )]
     fn run(self, builder: &Builder<'_>) -> ToolBuildResult {
-        let tool_result = builder.ensure(ToolBuild {
-            compiler: self.compiler,
+        builder.ensure(ToolBuild {
+            compiler: self.build_compiler,
             target: self.target,
             tool: "llvm-bitcode-linker",
             mode: Mode::ToolRustc,
             path: "src/tools/llvm-bitcode-linker",
             source_type: SourceType::InTree,
-            extra_features: self.extra_features,
+            extra_features: vec![],
             allow_features: "",
             cargo_args: Vec::new(),
             artifact_kind: ToolArtifactKind::Binary,
-        });
+        })
+    }
 
-        if tool_result.target_compiler.stage > 0 {
-            let bindir_self_contained = builder
-                .sysroot(tool_result.target_compiler)
-                .join(format!("lib/rustlib/{}/bin/self-contained", self.target.triple));
-            t!(fs::create_dir_all(&bindir_self_contained));
-            let bin_destination = bindir_self_contained
-                .join(exe("llvm-bitcode-linker", tool_result.target_compiler.host));
-            builder.copy_link(&tool_result.tool_path, &bin_destination, FileType::Executable);
-            ToolBuildResult {
-                tool_path: bin_destination,
-                build_compiler: tool_result.build_compiler,
-                target_compiler: tool_result.target_compiler,
-            }
-        } else {
-            tool_result
-        }
+    fn metadata(&self) -> Option<StepMetadata> {
+        Some(StepMetadata::build("LlvmBitcodeLinker", self.target).built_by(self.build_compiler))
     }
 }
 

src/bootstrap/src/core/builder/tests.rs

@@ -757,6 +757,58 @@ mod snapshot {
         ");
     }
 
+    #[test]
+    fn build_compiler_tools() {
+        let ctx = TestCtx::new();
+        insta::assert_snapshot!(
+            ctx
+                .config("build")
+                .stage(2)
+                .args(&["--set", "rust.lld=true", "--set", "rust.llvm-bitcode-linker=true"])
+                .render_steps(), @r"
+        [build] llvm <host>
+        [build] rustc 0 <host> -> rustc 1 <host>
+        [build] rustc 0 <host> -> LldWrapper 1 <host>
+        [build] rustc 1 <host> -> LlvmBitcodeLinker 2 <host>
+        [build] rustc 1 <host> -> std 1 <host>
+        [build] rustc 1 <host> -> rustc 2 <host>
+        [build] rustc 1 <host> -> LldWrapper 2 <host>
+        [build] rustc 2 <host> -> LlvmBitcodeLinker 3 <host>
+        [build] rustc 2 <host> -> std 2 <host>
+        [build] rustdoc 1 <host>
+        "
+        );
+    }
+
+    #[test]
+    fn build_compiler_tools_cross() {
+        let ctx = TestCtx::new();
+        insta::assert_snapshot!(
+            ctx
+                .config("build")
+                .stage(2)
+                .args(&["--set", "rust.lld=true", "--set", "rust.llvm-bitcode-linker=true"])
+                .hosts(&[TEST_TRIPLE_1])
+                .render_steps(), @r"
+        [build] llvm <host>
+        [build] rustc 0 <host> -> rustc 1 <host>
+        [build] rustc 0 <host> -> LldWrapper 1 <host>
+        [build] rustc 1 <host> -> LlvmBitcodeLinker 2 <host>
+        [build] rustc 1 <host> -> std 1 <host>
+        [build] rustc 1 <host> -> rustc 2 <host>
+        [build] rustc 1 <host> -> LldWrapper 2 <host>
+        [build] rustc 2 <host> -> LlvmBitcodeLinker 3 <host>
+        [build] rustc 1 <host> -> std 1 <target1>
+        [build] rustc 2 <host> -> std 2 <target1>
+        [build] llvm <target1>
+        [build] rustc 1 <host> -> rustc 2 <target1>
+        [build] rustc 1 <host> -> LldWrapper 2 <target1>
+        [build] rustc 2 <target1> -> LlvmBitcodeLinker 3 <target1>
+        [build] rustdoc 1 <target1>
+        "
+        );
+    }
+
     #[test]
     fn build_library_no_explicit_stage() {
         let ctx = TestCtx::new();
@@ -1040,6 +1092,7 @@ mod snapshot {
         [build] rustc 0 <host> -> cargo-clippy 1 <host>
         [build] rustc 0 <host> -> miri 1 <host>
         [build] rustc 0 <host> -> cargo-miri 1 <host>
+        [build] rustc 1 <host> -> LlvmBitcodeLinker 2 <host>
         ");
     }
 
@@ -1230,6 +1283,7 @@ mod snapshot {
         [build] rustc 0 <host> -> cargo-clippy 1 <target1>
         [build] rustc 0 <host> -> miri 1 <target1>
         [build] rustc 0 <host> -> cargo-miri 1 <target1>
+        [build] rustc 1 <host> -> LlvmBitcodeLinker 2 <target1>
         ");
     }
 

src/bootstrap/src/utils/tests/mod.rs

@@ -96,8 +96,6 @@ impl ConfigBuilder {
         // in-tree LLVM from sources.
         self.args.push("--set".to_string());
         self.args.push("llvm.download-ci-llvm=false".to_string());
-        self.args.push("--set".to_string());
-        self.args.push(format!("target.'{}'.llvm-config=false", get_host_target()));
 
         // Do not mess with the local rustc checkout build directory
         self.args.push("--build-dir".to_string());