1 files changed, 28 insertions, 0 deletions
diff --git a/lld/ELF/InputSection.cpp b/lld/ELF/InputSection.cpp
index 2f3cec3edec..ff084cd521a 100644
--- a/lld/ELF/InputSection.cpp
+++ b/lld/ELF/InputSection.cpp
@@ -44,6 +44,29 @@ std::string lld::toString(const InputSectionBase *Sec) {
   return (toString(Sec->File) + ":(" + Sec->Name + ")").str();
 }
 
+template <class ELFT> DenseMap<SectionBase *, int> elf::buildSectionOrder() {
+  // Build a map from symbols to their priorities. Symbols that didn't
+  // appear in the symbol ordering file have the lowest priority 0.
+  // All explicitly mentioned symbols have negative (higher) priorities.
+  DenseMap<StringRef, int> SymbolOrder;
+  int Priority = -Config->SymbolOrderingFile.size();
+  for (StringRef S : Config->SymbolOrderingFile)
+    SymbolOrder.insert({S, Priority++});
+
+  // Build a map from sections to their priorities.
+  DenseMap<SectionBase *, int> SectionOrder;
+  for (ObjFile<ELFT> *File : ObjFile<ELFT>::Instances) {
+    for (SymbolBody *Body : File->getSymbols()) {
+      auto *D = dyn_cast<DefinedRegular>(Body);
+      if (!D || !D->Section)
+        continue;
+      int &Priority = SectionOrder[D->Section];
+      Priority = std::min(Priority, SymbolOrder.lookup(D->getName()));
+    }
+  }
+  return SectionOrder;
+}
+
 template <class ELFT>
 static ArrayRef<uint8_t> getSectionContents(ObjFile<ELFT> *File,
                                             const typename ELFT::Shdr *Hdr) {
@@ -982,6 +1005,11 @@ uint64_t MergeInputSection::getOffset(uint64_t Offset) const {
   return Piece.OutputOff + Addend;
 }
 
+template DenseMap<SectionBase *, int> elf::buildSectionOrder<ELF32LE>();
+template DenseMap<SectionBase *, int> elf::buildSectionOrder<ELF32BE>();
+template DenseMap<SectionBase *, int> elf::buildSectionOrder<ELF64LE>();
+template DenseMap<SectionBase *, int> elf::buildSectionOrder<ELF64BE>();
+
 template InputSection::InputSection(ObjFile<ELF32LE> *, const ELF32LE::Shdr *,
                                     StringRef);
 template InputSection::InputSection(ObjFile<ELF32BE> *, const ELF32BE::Shdr *,