[Mips] Fix addend writing for R_MIPS_REL32 relocation

llvm-svn: 242760

2 files changed, 20 insertions, 11 deletions

diff --git a/lld/lib/ReaderWriter/ELF/Mips/MipsRelocationHandler.cpp b/lld/lib/ReaderWriter/ELF/Mips/MipsRelocationHandler.cpp
index c0feb735960..66267c6a318 100644
--- a/lld/lib/ReaderWriter/ELF/Mips/MipsRelocationHandler.cpp
+++ b/lld/lib/ReaderWriter/ELF/Mips/MipsRelocationHandler.cpp
@@ -320,12 +320,12 @@ static ErrorOr<int64_t> relocJalr(uint64_t P, uint64_t S, bool isCrossJump,
   return ins;
 }
 
-static int64_t relocRel32(int64_t A) {
+static int64_t relocRel32(uint64_t S, int64_t A, bool isLocal) {
   // If output relocation format is REL and the input one is RELA, the only
   // method to transfer the relocation addend from the input relocation
   // to the output dynamic relocation is to save this addend to the location
   // modified by R_MIPS_REL32.
-  return A;
+  return isLocal ? S + A : A;
 }
 
 static std::error_code adjustJumpOpCode(uint64_t &ins, uint64_t tgt,
@@ -383,8 +383,8 @@ template <class ELFT>
 static ErrorOr<int64_t>
 calculateRelocation(Reference::KindValue kind, Reference::Addend addend,
                     uint64_t tgtAddr, uint64_t relAddr, uint64_t gpAddr,
-                    bool isGP, bool isCrossJump, bool isDynamic,
-                    uint8_t *location) {
+                    uint8_t *location, bool isGP, bool isCrossJump,
+                    bool isDynamic, bool isLocalSym) {
   switch (kind) {
   case R_MIPS_NONE:
     return 0;
@@ -490,7 +490,7 @@ calculateRelocation(Reference::KindValue kind, Reference::Addend addend,
     // We do not do JALR optimization now.
     return 0;
   case R_MIPS_REL32:
-    return relocRel32(addend);
+    return relocRel32(tgtAddr, addend, isLocalSym);
   case R_MIPS_JUMP_SLOT:
   case R_MIPS_COPY:
     // Ignore runtime relocations.
@@ -585,6 +585,12 @@ static uint8_t getRelShift(Reference::KindValue kind,
   return shift;
 }
 
+static bool isLocalTarget(const Atom *a) {
+  if (auto *da = dyn_cast<DefinedAtom>(a))
+    return da->scope() == Atom::scopeTranslationUnit;
+  return false;
+}
+
 template <class ELFT>
 std::error_code RelocationHandler<ELFT>::applyRelocation(
     ELFWriter &writer, llvm::FileOutputBuffer &buf, const AtomLayout &atom,
@@ -595,6 +601,7 @@ std::error_code RelocationHandler<ELFT>::applyRelocation(
 
   uint64_t gpAddr = _targetLayout.getGPAddr();
   bool isGpDisp = ref.target()->name() == "_gp_disp";
+  bool isLocalSym = isLocalTarget(ref.target());
 
   uint8_t *atomContent = buf.getBufferStart() + atom._fileOffset;
   uint8_t *location = atomContent + ref.offsetInAtom();
@@ -616,8 +623,9 @@ std::error_code RelocationHandler<ELFT>::applyRelocation(
     if (kind == R_MIPS_NONE)
       break;
     auto params = getRelocationParams(kind);
-    res = calculateRelocation<ELFT>(kind, *res, sym, relAddr, gpAddr, isGpDisp,
-                                    isCrossJump, _ctx.isDynamic(), location);
+    res = calculateRelocation<ELFT>(kind, *res, sym, relAddr, gpAddr, location,
+                                    isGpDisp, isCrossJump, _ctx.isDynamic(),
+                                    isLocalSym);
     if (auto ec = res.getError())
       return ec;
     // Check result for the last relocation only.
diff --git a/lld/lib/ReaderWriter/ELF/Mips/MipsRelocationPass.cpp b/lld/lib/ReaderWriter/ELF/Mips/MipsRelocationPass.cpp
index 99d2ccf9676..75a9ae57170 100644
--- a/lld/lib/ReaderWriter/ELF/Mips/MipsRelocationPass.cpp
+++ b/lld/lib/ReaderWriter/ELF/Mips/MipsRelocationPass.cpp
@@ -586,7 +586,8 @@ std::error_code RelocationPass<ELFT>::perform(SimpleFile &mf) {
 
   // Create R_MIPS_REL32 relocations.
   for (auto *ref : _rel32Candidates) {
-    if (!isDynamic(ref->target()) || hasPLTEntry(ref->target()))
+    bool forceRel = isLocal(ref->target()) && _ctx.getOutputELFType() == ET_DYN;
+    if (!forceRel && (!isDynamic(ref->target()) || hasPLTEntry(ref->target())))
       continue;
     ref->setKindValue(R_MIPS_REL32);
     if (ELFT::Is64Bits)
@@ -817,10 +818,10 @@ RelocationPass<ELFT>::collectReferenceInfo(const MipsELFDefinedAtom<ELFT> &atom,
   if (!isConstrainSym(atom, refKind))
     return std::error_code();
 
-  if (mightBeDynamic(atom, refKind))
-    _rel32Candidates.push_back(&ref);
-  else
+  if (!mightBeDynamic(atom, refKind))
     _hasStaticRelocations.insert(ref.target());
+  else if (refKind == R_MIPS_32 || refKind == R_MIPS_64)
+    _rel32Candidates.push_back(&ref);
 
   if (!isBranchReloc(refKind) && !isAllCallReloc(refKind) &&
       refKind != R_MIPS_EH)