[lld] f855074 - [ELF] GnuHashTableSection: replace stable_sort with 2-key sort. NFC

[Fangrui Song via llvm-commits]

Author: Fangrui Song
Date: 2022-01-17T00:34:42-08:00
New Revision: f855074ed1193d5fd96b02280c31479294ce0901

URL: https://github.com/llvm/llvm-project/commit/f855074ed1193d5fd96b02280c31479294ce0901
DIFF: https://github.com/llvm/llvm-project/commit/f855074ed1193d5fd96b02280c31479294ce0901.diff

LOG: [ELF] GnuHashTableSection: replace stable_sort with 2-key sort. NFC

strTabOffset stabilizes llvm::sort. My x86-64 executable is 5+KiB smaller.

Added: 
    

Modified: 
    lld/ELF/SyntheticSections.cpp

Removed: 
    


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diff  --git a/lld/ELF/SyntheticSections.cpp b/lld/ELF/SyntheticSections.cpp
index f20000ab7a3b..3e6773545142 100644
--- a/lld/ELF/SyntheticSections.cpp
+++ b/lld/ELF/SyntheticSections.cpp
@@ -2478,8 +2478,9 @@ void GnuHashTableSection::addSymbols(SmallVectorImpl<SymbolTableEntry> &v) {
     symbols.push_back({b, ent.strTabOffset, hash, bucketIdx});
   }
 
-  llvm::stable_sort(symbols, [](const Entry &l, const Entry &r) {
-    return l.bucketIdx < r.bucketIdx;
+  llvm::sort(symbols, [](const Entry &l, const Entry &r) {
+    return std::tie(l.bucketIdx, l.strTabOffset) <
+           std::tie(r.bucketIdx, r.strTabOffset);
   });
 
   v.erase(mid, v.end());