[Mips] Sort R_MIPS_LO16 / R_MIPS_HI16 / R_MIPS_GOT16 before finding

pairs and calculate AHL addend.

llvm-svn: 204606

1 files changed, 29 insertions, 9 deletions

diff --git a/lld/lib/ReaderWriter/ELF/Mips/MipsRelocationPass.cpp b/lld/lib/ReaderWriter/ELF/Mips/MipsRelocationPass.cpp
index 1cf3493b456..ee2ab033ca5 100644
--- a/lld/lib/ReaderWriter/ELF/Mips/MipsRelocationPass.cpp
+++ b/lld/lib/ReaderWriter/ELF/Mips/MipsRelocationPass.cpp
@@ -266,27 +266,47 @@ inline int64_t calcAHL(int64_t AHI, int64_t ALO) {
 
 template <typename ELFT>
 void RelocationPass<ELFT>::calculateAHLs(const DefinedAtom &atom) {
-  std::vector<Reference *> references;
+  std::vector<const Reference *> lo16Refs;
+  std::vector<Reference *> hi16Refs;
   for (const auto &ref : atom) {
     if (ref->kindNamespace() != lld::Reference::KindNamespace::ELF)
       continue;
     assert(ref->kindArch() == Reference::KindArch::Mips);
     switch (ref->kindValue()) {
     case R_MIPS_HI16:
-      references.push_back(const_cast<Reference *>(ref));
+      hi16Refs.push_back(const_cast<Reference *>(ref));
+    case R_MIPS_LO16:
+      lo16Refs.push_back(ref);
       break;
     case R_MIPS_GOT16:
       if (isLocal(ref->target()))
-        references.push_back(const_cast<Reference *>(ref));
-      break;
-    case R_MIPS_LO16:
-      for (auto &sr : references)
-        sr->setAddend(calcAHL(sr->addend(), ref->addend()));
-      references.clear();
+        hi16Refs.push_back(const_cast<Reference *>(ref));
       break;
     }
   }
-  assert(references.empty());
+
+  std::sort(lo16Refs.begin(), lo16Refs.end(),
+            [](const Reference *a, const Reference *b) {
+    return a->offsetInAtom() < b->offsetInAtom();
+  });
+  std::sort(hi16Refs.begin(), hi16Refs.end(),
+            [](const Reference *a, const Reference *b) {
+    return a->offsetInAtom() < b->offsetInAtom();
+  });
+
+  // Iterate over R_MIPS_LO16 relocations sorted by theirs offsets in the atom.
+  // Calculate AHL addend for each R_MIPS_HI16 amd R_MIPS_GOT16 relocation
+  // precedes the current R_MIPS_LO16 one.
+
+  auto hic = hi16Refs.begin();
+  for (const auto &lo : lo16Refs) {
+    for (; hic != hi16Refs.end(); ++hic) {
+      if ((*hic)->offsetInAtom() > lo->offsetInAtom())
+        break;
+      (*hic)->setAddend(calcAHL((*hic)->addend(), lo->addend()));
+    }
+  }
+  assert(hic == hi16Refs.end());
 }
 
 template <typename ELFT>