boulder-data: Support mold linker

Mold is often noticeably faster than LLD (and much faster than BFD) and is already used by numerous packages for that reason. Make it more ergonomic to use by adding a top-level `mold` key which adds it as a builddep and sets environmental flags appropriately to use it. Tested with both the gnu and LLVM toolchains. Signed-off-by: Reilly Brogan <[email protected]>
serpent-os · Jan 14, 2025 · ec2ef81 · ec2ef81
1 parent ffe8a27
commit ec2ef81
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Showing 3 changed files with 25 additions and 5 deletions.
diff --git a/boulder/src/build/job/phase.rs b/boulder/src/build/job/phase.rs
@@ -178,7 +178,6 @@ impl Phase {
             parser.add_definition("compiler_objcxxcpp", "clang++ -E");
             parser.add_definition("compiler_d", "ldc2");
             parser.add_definition("compiler_ar", "llvm-ar");
-            parser.add_definition("compiler_ld", "ld.lld");
             parser.add_definition("compiler_objcopy", "llvm-objcopy");
             parser.add_definition("compiler_nm", "llvm-nm");
             parser.add_definition("compiler_ranlib", "llvm-ranlib");
@@ -194,14 +193,21 @@ impl Phase {
             parser.add_definition("compiler_objcxxcpp", "g++ -E");
             parser.add_definition("compiler_d", "ldc2"); // FIXME: GDC
             parser.add_definition("compiler_ar", "gcc-ar");
-            parser.add_definition("compiler_ld", "ld.bfd");
             parser.add_definition("compiler_objcopy", "objcopy");
             parser.add_definition("compiler_nm", "gcc-nm");
             parser.add_definition("compiler_ranlib", "gcc-ranlib");
             parser.add_definition("compiler_strip", "strip");
             parser.add_definition("compiler_path", path);
         }
 
+        if recipe.parsed.mold {
+            parser.add_definition("compiler_ld", "ld.mold");
+        } else if matches!(recipe.parsed.options.toolchain, Toolchain::Llvm) {
+            parser.add_definition("compiler_ld", "ld.lld");
+        } else {
+            parser.add_definition("compiler_ld", "ld.bfd");
+        }
+
         /* Allow packagers to do stage specific actions in a pgo build */
         if matches!(pgo_stage, Some(pgo::Stage::One)) {
             parser.add_definition("pgo_stage", "ONE");
@@ -346,12 +352,12 @@ fn add_tuning(
     let toolchain = recipe.parsed.options.toolchain;
     let flags = tuning.build()?;
 
-    let cflags = fmt_flags(
+    let mut cflags = fmt_flags(
         flags
             .iter()
             .filter_map(|flag| flag.get(tuning::CompilerFlag::C, toolchain)),
     );
-    let cxxflags = fmt_flags(
+    let mut cxxflags = fmt_flags(
         flags
             .iter()
             .filter_map(|flag| flag.get(tuning::CompilerFlag::Cxx, toolchain)),
@@ -366,12 +372,18 @@ fn add_tuning(
             .iter()
             .filter_map(|flag| flag.get(tuning::CompilerFlag::D, toolchain)),
     );
-    let rustflags = fmt_flags(
+    let mut rustflags = fmt_flags(
         flags
             .iter()
             .filter_map(|flag| flag.get(tuning::CompilerFlag::Rust, toolchain)),
     );
 
+    if recipe.parsed.mold {
+        cflags.push_str(" -fuse-ld=mold");
+        cxxflags.push_str(" -fuse-ld=mold");
+        rustflags.push_str(" -Clink-arg=-fuse-ld=mold");
+    }
+
     parser.add_definition("cflags", cflags);
     parser.add_definition("cxxflags", cxxflags);
     parser.add_definition("ldflags", ldflags);

diff --git a/boulder/src/build/root.rs b/boulder/src/build/root.rs
@@ -103,6 +103,10 @@ fn packages(builder: &Builder) -> Vec<&str> {
         }
     }
 
+    if builder.recipe.parsed.mold {
+        packages.extend(MOLD_PACKAGES);
+    }
+
     if builder.ccache {
         packages.extend(CCACHE_PACKAGES);
     }
@@ -203,6 +207,8 @@ const GNU32_PACKAGES: &[&str] = &["gcc-32bit", "g++-32bit"];
 const LLVM_PACKAGES: &[&str] = &["clang"];
 const LLVM32_PACKAGES: &[&str] = &["clang-32bit", "libcxx-32bit-devel"];
 
+const MOLD_PACKAGES: &[&str] = &["binary(mold)"];
+
 const CCACHE_PACKAGES: &[&str] = &["binary(ccache)", "binary(sccache)"];
 
 #[derive(Debug, Error)]

diff --git a/crates/stone_recipe/src/lib.rs b/crates/stone_recipe/src/lib.rs
@@ -48,6 +48,8 @@ pub struct Recipe {
     pub tuning: Vec<KeyValue<Tuning>>,
     #[serde(default, deserialize_with = "stringy_bool")]
     pub emul32: bool,
+    #[serde(default, deserialize_with = "stringy_bool")]
+    pub mold: bool,
 }
 
 #[derive(Debug, Clone)]