Exclude unnecessary info from CodegenResults

`foreign_module` and `wasm_import_module` are not needed for linking,
and hence can be removed from CodegenResults.

Author: Victor Ding

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -2,7 +2,7 @@ use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::temp_dir::MaybeTempDir;
 use rustc_fs_util::fix_windows_verbatim_for_gcc;
 use rustc_hir::def_id::CrateNum;
-use rustc_middle::middle::cstore::{EncodedMetadata, LibSource, NativeLib};
+use rustc_middle::middle::cstore::{EncodedMetadata, LibSource};
 use rustc_middle::middle::dependency_format::Linkage;
 use rustc_session::config::{self, CFGuard, CrateType, DebugInfo};
 use rustc_session::config::{OutputFilenames, OutputType, PrintRequest, SanitizerSet};
@@ -22,7 +22,8 @@ use super::command::Command;
 use super::linker::{self, Linker};
 use super::rpath::{self, RPathConfig};
 use crate::{
-    looks_like_rust_object_file, CodegenResults, CompiledModule, CrateInfo, METADATA_FILENAME,
+    looks_like_rust_object_file, CodegenResults, CompiledModule, CrateInfo, NativeLib,
+    METADATA_FILENAME,
 };
 
 use cc::windows_registry;

compiler/rustc_codegen_ssa/src/base.rs

@@ -766,7 +766,7 @@ impl CrateInfo {
             profiler_runtime: None,
             is_no_builtins: Default::default(),
             native_libraries: Default::default(),
-            used_libraries: tcx.native_libraries(LOCAL_CRATE),
+            used_libraries: tcx.native_libraries(LOCAL_CRATE).iter().map(Into::into).collect(),
             link_args: tcx.link_args(LOCAL_CRATE),
             crate_name: Default::default(),
             used_crates_dynamic: cstore::used_crates(tcx, LinkagePreference::RequireDynamic),
@@ -787,7 +787,8 @@ impl CrateInfo {
         info.missing_lang_items.reserve(n_crates);
 
         for &cnum in crates.iter() {
-            info.native_libraries.insert(cnum, tcx.native_libraries(cnum));
+            info.native_libraries
+                .insert(cnum, tcx.native_libraries(cnum).iter().map(Into::into).collect());
             info.crate_name.insert(cnum, tcx.crate_name(cnum).to_string());
             info.used_crate_source.insert(cnum, tcx.used_crate_source(cnum));
             if tcx.is_panic_runtime(cnum) {

compiler/rustc_codegen_ssa/src/lib.rs

@@ -21,15 +21,17 @@ extern crate tracing;
 #[macro_use]
 extern crate rustc_middle;
 
+use rustc_ast as ast;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::sync::Lrc;
 use rustc_hir::def_id::CrateNum;
 use rustc_hir::LangItem;
 use rustc_middle::dep_graph::WorkProduct;
-use rustc_middle::middle::cstore::{CrateSource, LibSource, NativeLib};
+use rustc_middle::middle::cstore::{self, CrateSource, LibSource};
 use rustc_middle::middle::dependency_format::Dependencies;
 use rustc_middle::ty::query::Providers;
 use rustc_session::config::{OutputFilenames, OutputType, RUST_CGU_EXT};
+use rustc_session::utils::NativeLibKind;
 use rustc_span::symbol::Symbol;
 use std::path::{Path, PathBuf};
 
@@ -105,6 +107,19 @@ bitflags::bitflags! {
     }
 }
 
+#[derive(Clone, Debug, Encodable, Decodable, HashStable)]
+pub struct NativeLib {
+    pub kind: NativeLibKind,
+    pub name: Option<Symbol>,
+    pub cfg: Option<ast::MetaItem>,
+}
+
+impl From<&cstore::NativeLib> for NativeLib {
+    fn from(lib: &cstore::NativeLib) -> Self {
+        NativeLib { kind: lib.kind.clone(), name: lib.name.clone(), cfg: lib.cfg.clone() }
+    }
+}
+
 /// Misc info we load from metadata to persist beyond the tcx.
 ///
 /// Note: though `CrateNum` is only meaningful within the same tcx, information within `CrateInfo`
@@ -119,9 +134,9 @@ pub struct CrateInfo {
     pub compiler_builtins: Option<CrateNum>,
     pub profiler_runtime: Option<CrateNum>,
     pub is_no_builtins: FxHashSet<CrateNum>,
-    pub native_libraries: FxHashMap<CrateNum, Lrc<Vec<NativeLib>>>,
+    pub native_libraries: FxHashMap<CrateNum, Vec<NativeLib>>,
     pub crate_name: FxHashMap<CrateNum, String>,
-    pub used_libraries: Lrc<Vec<NativeLib>>,
+    pub used_libraries: Vec<NativeLib>,
     pub link_args: Lrc<Vec<String>>,
     pub used_crate_source: FxHashMap<CrateNum, Lrc<CrateSource>>,
     pub used_crates_static: Vec<(CrateNum, LibSource)>,