Save pre-link bitcode to `ModuleCodegen`

3 files changed, 21 insertions, 5 deletions

diff --git a/compiler/rustc_codegen_ssa/src/back/write.rs b/compiler/rustc_codegen_ssa/src/back/write.rs
index 47e7dec48e4..927c9d1fa1e 100644
--- a/compiler/rustc_codegen_ssa/src/back/write.rs
+++ b/compiler/rustc_codegen_ssa/src/back/write.rs
@@ -278,6 +278,10 @@ impl ModuleConfig {
             || self.emit_obj == EmitObj::Bitcode
             || self.emit_obj == EmitObj::ObjectCode(BitcodeSection::Full)
     }
+
+    pub fn embed_bitcode(&self) -> bool {
+        self.emit_obj == EmitObj::ObjectCode(BitcodeSection::Full)
+    }
 }
 
 /// Configuration passed to the function returned by the `target_machine_factory`.
@@ -880,14 +884,14 @@ pub(crate) fn compute_per_cgu_lto_type(
 
 fn execute_optimize_work_item<B: ExtraBackendMethods>(
     cgcx: &CodegenContext<B>,
-    module: ModuleCodegen<B::Module>,
+    mut module: ModuleCodegen<B::Module>,
     module_config: &ModuleConfig,
 ) -> Result<WorkItemResult<B>, FatalError> {
     let dcx = cgcx.create_dcx();
     let dcx = dcx.handle();
 
     unsafe {
-        B::optimize(cgcx, dcx, &module, module_config)?;
+        B::optimize(cgcx, dcx, &mut module, module_config)?;
     }
 
     // After we've done the initial round of optimizations we need to
diff --git a/compiler/rustc_codegen_ssa/src/lib.rs b/compiler/rustc_codegen_ssa/src/lib.rs
index 3ddae7c670a..4e758bfdec3 100644
--- a/compiler/rustc_codegen_ssa/src/lib.rs
+++ b/compiler/rustc_codegen_ssa/src/lib.rs
@@ -75,15 +75,27 @@ pub struct ModuleCodegen<M> {
     pub name: String,
     pub module_llvm: M,
     pub kind: ModuleKind,
+    /// Saving the ThinLTO buffer for embedding in the object file.
+    pub thin_lto_buffer: Option<Vec<u8>>,
 }
 
 impl<M> ModuleCodegen<M> {
     pub fn new_regular(name: impl Into<String>, module: M) -> Self {
-        Self { name: name.into(), module_llvm: module, kind: ModuleKind::Regular }
+        Self {
+            name: name.into(),
+            module_llvm: module,
+            kind: ModuleKind::Regular,
+            thin_lto_buffer: None,
+        }
     }
 
     pub fn new_allocator(name: impl Into<String>, module: M) -> Self {
-        Self { name: name.into(), module_llvm: module, kind: ModuleKind::Allocator }
+        Self {
+            name: name.into(),
+            module_llvm: module,
+            kind: ModuleKind::Allocator,
+            thin_lto_buffer: None,
+        }
     }
 
     pub fn into_compiled_module(
diff --git a/compiler/rustc_codegen_ssa/src/traits/write.rs b/compiler/rustc_codegen_ssa/src/traits/write.rs
index 97fe614aa10..c77efdd1728 100644
--- a/compiler/rustc_codegen_ssa/src/traits/write.rs
+++ b/compiler/rustc_codegen_ssa/src/traits/write.rs
@@ -40,7 +40,7 @@ pub trait WriteBackendMethods: 'static + Sized + Clone {
     unsafe fn optimize(
         cgcx: &CodegenContext<Self>,
         dcx: DiagCtxtHandle<'_>,
-        module: &ModuleCodegen<Self::Module>,
+        module: &mut ModuleCodegen<Self::Module>,
         config: &ModuleConfig,
     ) -> Result<(), FatalError>;
     fn optimize_fat(