1 files changed, 56 insertions, 2 deletions

diff --git a/lld/ELF/OutputSections.cpp b/lld/ELF/OutputSections.cpp
index f1eba00145f..1c8311c9864 100644
--- a/lld/ELF/OutputSections.cpp
+++ b/lld/ELF/OutputSections.cpp
@@ -94,6 +94,17 @@ GotSection<ELFT>::getEntryAddr(const SymbolBody &B) const {
   return this->getVA() + B.GotIndex * sizeof(uintX_t);
 }
 
+template <class ELFT>
+const SymbolBody *GotSection<ELFT>::getMipsFirstGlobalEntry() const {
+  return Entries.empty() ? nullptr : Entries.front();
+}
+
+template <class ELFT>
+unsigned GotSection<ELFT>::getMipsLocalEntriesNum() const {
+  // TODO: Update when the suppoort of GOT entries for local symbols is added.
+  return Target->getGotHeaderEntriesNum();
+}
+
 template <class ELFT> void GotSection<ELFT>::finalize() {
   this->Header.sh_size =
       (Target->getGotHeaderEntriesNum() + Entries.size()) * sizeof(uintX_t);
@@ -477,6 +488,12 @@ DynamicSection<ELFT>::DynamicSection(SymbolTable<ELFT> &SymTab)
   Elf_Shdr &Header = this->Header;
   Header.sh_addralign = ELFT::Is64Bits ? 8 : 4;
   Header.sh_entsize = ELFT::Is64Bits ? 16 : 8;
+
+  // .dynamic section is not writable on MIPS.
+  // See "Special Section" in Chapter 4 in the following document:
+  // ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf
+  if (Config->EMachine == EM_MIPS)
+    Header.sh_flags = llvm::ELF::SHF_ALLOC;
 }
 
 template <class ELFT> void DynamicSection<ELFT>::finalize() {
@@ -495,7 +512,7 @@ template <class ELFT> void DynamicSection<ELFT>::finalize() {
   if (Out<ELFT>::RelaPlt && Out<ELFT>::RelaPlt->hasRelocs()) {
     ++NumEntries; // DT_JMPREL
     ++NumEntries; // DT_PLTRELSZ
-    ++NumEntries; // DT_PLTGOT
+    ++NumEntries; // DT_PLTGOT / DT_MIPS_PLTGOT
     ++NumEntries; // DT_PLTREL
   }
 
@@ -558,6 +575,19 @@ template <class ELFT> void DynamicSection<ELFT>::finalize() {
     ++NumEntries; // DT_FLAGS
   if (DtFlags1)
     ++NumEntries; // DT_FLAGS_1
+
+  if (Config->EMachine == EM_MIPS) {
+    ++NumEntries; // DT_MIPS_RLD_VERSION
+    ++NumEntries; // DT_MIPS_FLAGS
+    ++NumEntries; // DT_MIPS_BASE_ADDRESS
+    ++NumEntries; // DT_MIPS_SYMTABNO
+    ++NumEntries; // DT_MIPS_LOCAL_GOTNO
+    ++NumEntries; // DT_MIPS_GOTSYM;
+    ++NumEntries; // DT_PLTGOT
+    if (Out<ELFT>::MipsRldMap)
+      ++NumEntries; // DT_MIPS_RLD_MAP
+  }
+
   ++NumEntries; // DT_NULL
 
   Header.sh_size = NumEntries * Header.sh_entsize;
@@ -588,7 +618,12 @@ template <class ELFT> void DynamicSection<ELFT>::writeTo(uint8_t *Buf) {
   if (Out<ELFT>::RelaPlt && Out<ELFT>::RelaPlt->hasRelocs()) {
     WritePtr(DT_JMPREL, Out<ELFT>::RelaPlt->getVA());
     WriteVal(DT_PLTRELSZ, Out<ELFT>::RelaPlt->getSize());
-    WritePtr(DT_PLTGOT, Out<ELFT>::GotPlt->getVA());
+    // On MIPS, the address of the .got.plt section is stored in
+    // the DT_MIPS_PLTGOT entry because the DT_PLTGOT entry points to
+    // the .got section. See "Dynamic Section" in the following document:
+    // https://sourceware.org/ml/binutils/2008-07/txt00000.txt
+    WritePtr((Config->EMachine == EM_MIPS) ? DT_MIPS_PLTGOT : DT_PLTGOT,
+             Out<ELFT>::GotPlt->getVA());
     WriteVal(DT_PLTREL, Out<ELFT>::RelaPlt->isRela() ? DT_RELA : DT_REL);
   }
 
@@ -640,6 +675,25 @@ template <class ELFT> void DynamicSection<ELFT>::writeTo(uint8_t *Buf) {
     WriteVal(DT_FLAGS, DtFlags);
   if (DtFlags1)
     WriteVal(DT_FLAGS_1, DtFlags1);
+
+  // See "Dynamic Section" in Chapter 5 in the following document
+  // for detailed description:
+  // ftp://www.linux-mips.org/pub/linux/mips/doc/ABI/mipsabi.pdf
+  if (Config->EMachine == EM_MIPS) {
+    WriteVal(DT_MIPS_RLD_VERSION, 1);
+    WriteVal(DT_MIPS_FLAGS, RHF_NOTPOT);
+    WritePtr(DT_MIPS_BASE_ADDRESS, Target->getVAStart());
+    WriteVal(DT_MIPS_SYMTABNO, Out<ELFT>::DynSymTab->getNumSymbols());
+    WriteVal(DT_MIPS_LOCAL_GOTNO, Out<ELFT>::Got->getMipsLocalEntriesNum());
+    if (const SymbolBody *B = Out<ELFT>::Got->getMipsFirstGlobalEntry())
+      WriteVal(DT_MIPS_GOTSYM, B->getDynamicSymbolTableIndex());
+    else
+      WriteVal(DT_MIPS_GOTSYM, Out<ELFT>::DynSymTab->getNumSymbols());
+    WritePtr(DT_PLTGOT, Out<ELFT>::Got->getVA());
+    if (Out<ELFT>::MipsRldMap)
+      WritePtr(DT_MIPS_RLD_MAP, Out<ELFT>::MipsRldMap->getVA());
+  }
+
   WriteVal(DT_NULL, 0);
 }