Auto merge of #120931 - chenyukang:yukang-cleanup-hashmap, r=michaelwoerister

Clean up potential_query_instability with FxIndexMap and UnordMap

From https://github.com/rust-lang/rust/pull/120485#issuecomment-1916437191

r? `@michaelwoerister`

2 files changed, 3 insertions, 4 deletions

diff --git a/compiler/rustc_codegen_llvm/src/back/lto.rs b/compiler/rustc_codegen_llvm/src/back/lto.rs
index 42bd8687042..06a681c24e6 100644
--- a/compiler/rustc_codegen_llvm/src/back/lto.rs
+++ b/compiler/rustc_codegen_llvm/src/back/lto.rs
@@ -21,6 +21,7 @@ use rustc_middle::dep_graph::WorkProduct;
 use rustc_middle::middle::exported_symbols::{SymbolExportInfo, SymbolExportLevel};
 use rustc_session::config::{self, CrateType, Lto};
 
+use std::collections::BTreeMap;
 use std::ffi::{CStr, CString};
 use std::fs::File;
 use std::io;
@@ -787,7 +788,7 @@ pub unsafe fn optimize_thin_module(
 #[derive(Debug, Default)]
 pub struct ThinLTOKeysMap {
     // key = llvm name of importing module, value = LLVM cache key
-    keys: FxHashMap<String, String>,
+    keys: BTreeMap<String, String>,
 }
 
 impl ThinLTOKeysMap {
@@ -797,7 +798,6 @@ impl ThinLTOKeysMap {
         let mut writer = io::BufWriter::new(file);
         // The entries are loaded back into a hash map in `load_from_file()`, so
         // the order in which we write them to file here does not matter.
-        #[allow(rustc::potential_query_instability)]
         for (module, key) in &self.keys {
             writeln!(writer, "{module} {key}")?;
         }
@@ -806,7 +806,7 @@ impl ThinLTOKeysMap {
 
     fn load_from_file(path: &Path) -> io::Result<Self> {
         use std::io::BufRead;
-        let mut keys = FxHashMap::default();
+        let mut keys = BTreeMap::default();
         let file = File::open(path)?;
         for line in io::BufReader::new(file).lines() {
             let line = line?;
diff --git a/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs b/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs
index b1ceb1d4dd5..6116a6fd222 100644
--- a/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs
+++ b/compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs
@@ -403,7 +403,6 @@ fn codegenned_and_inlined_items(tcx: TyCtxt<'_>) -> DefIdSet {
     let mut result = items.clone();
 
     for cgu in cgus {
-        #[allow(rustc::potential_query_instability)]
         for item in cgu.items().keys() {
             if let mir::mono::MonoItem::Fn(ref instance) = item {
                 let did = instance.def_id();