From 8371a036ea485ef8a830349c779e5acc116cfd8d Mon Sep 17 00:00:00 2001
From: David Wood <david.wood@huawei.com>
Date: Mon, 4 Jul 2022 14:38:42 +0100
Subject: incr: cache dwarf objects in work products

Cache DWARF objects alongside object files in work products when those
exist so that DWARF object files are available for thorin in packed mode
in incremental scenarios.

Signed-off-by: David Wood <david.wood@huawei.com>
---
 compiler/rustc_codegen_ssa/src/back/write.rs | 75 +++++++++++++++++++---------
 1 file changed, 51 insertions(+), 24 deletions(-)

(limited to 'compiler/rustc_codegen_ssa/src')

diff --git a/compiler/rustc_codegen_ssa/src/back/write.rs b/compiler/rustc_codegen_ssa/src/back/write.rs
index 632f07c5c2d..f4a5cac872e 100644
--- a/compiler/rustc_codegen_ssa/src/back/write.rs
+++ b/compiler/rustc_codegen_ssa/src/back/write.rs
@@ -494,12 +494,18 @@ fn copy_all_cgu_workproducts_to_incr_comp_cache_dir(
     let _timer = sess.timer("copy_all_cgu_workproducts_to_incr_comp_cache_dir");
 
     for module in compiled_modules.modules.iter().filter(|m| m.kind == ModuleKind::Regular) {
-        if let Some(path) = &module.object {
-            if let Some((id, product)) =
-                copy_cgu_workproduct_to_incr_comp_cache_dir(sess, &module.name, path)
-            {
-                work_products.insert(id, product);
-            }
+        let mut files = Vec::new();
+        if let Some(object_file_path) = &module.object {
+            files.push(("o", object_file_path.as_path()));
+        }
+        if let Some(dwarf_object_file_path) = &module.dwarf_object {
+            files.push(("dwo", dwarf_object_file_path.as_path()));
+        }
+
+        if let Some((id, product)) =
+            copy_cgu_workproduct_to_incr_comp_cache_dir(sess, &module.name, files.as_slice())
+        {
+            work_products.insert(id, product);
         }
     }
 
@@ -856,29 +862,50 @@ fn execute_copy_from_cache_work_item<B: ExtraBackendMethods>(
     assert!(module_config.emit_obj != EmitObj::None);
 
     let incr_comp_session_dir = cgcx.incr_comp_session_dir.as_ref().unwrap();
-    let obj_out = cgcx.output_filenames.temp_path(OutputType::Object, Some(&module.name));
-    let source_file = in_incr_comp_dir(&incr_comp_session_dir, &module.source.saved_file);
-    debug!(
-        "copying pre-existing module `{}` from {:?} to {}",
-        module.name,
-        source_file,
-        obj_out.display()
+
+    let load_from_incr_comp_dir = |output_path: PathBuf, saved_path: &str| {
+        let source_file = in_incr_comp_dir(&incr_comp_session_dir, saved_path);
+        debug!(
+            "copying pre-existing module `{}` from {:?} to {}",
+            module.name,
+            source_file,
+            output_path.display()
+        );
+        match link_or_copy(&source_file, &output_path) {
+            Ok(_) => Some(output_path),
+            Err(err) => {
+                let diag_handler = cgcx.create_diag_handler();
+                diag_handler.err(&format!(
+                    "unable to copy {} to {}: {}",
+                    source_file.display(),
+                    output_path.display(),
+                    err
+                ));
+                None
+            }
+        }
+    };
+
+    let object = load_from_incr_comp_dir(
+        cgcx.output_filenames.temp_path(OutputType::Object, Some(&module.name)),
+        &module.source.saved_files.get("o").expect("no saved object file in work product"),
     );
-    if let Err(err) = link_or_copy(&source_file, &obj_out) {
-        let diag_handler = cgcx.create_diag_handler();
-        diag_handler.err(&format!(
-            "unable to copy {} to {}: {}",
-            source_file.display(),
-            obj_out.display(),
-            err
-        ));
-    }
+    let dwarf_object =
+        module.source.saved_files.get("dwo").as_ref().and_then(|saved_dwarf_object_file| {
+            let dwarf_obj_out = cgcx
+                .output_filenames
+                .split_dwarf_path(cgcx.split_debuginfo, cgcx.split_dwarf_kind, Some(&module.name))
+                .expect(
+                    "saved dwarf object in work product but `split_dwarf_path` returned `None`",
+                );
+            load_from_incr_comp_dir(dwarf_obj_out, &saved_dwarf_object_file)
+        });
 
     WorkItemResult::Compiled(CompiledModule {
         name: module.name,
         kind: ModuleKind::Regular,
-        object: Some(obj_out),
-        dwarf_object: None,
+        object,
+        dwarf_object,
         bytecode: None,
     })
 }
-- 
cgit 1.4.1-3-g733a5