[ARM] Implement R_ARM_GLOB_DAT for GOT entries

This is used when referencing global or static data in shared
objects. This is also used when function's address is taken and
function call is made indirectly.

llvm-svn: 238014

3 files changed, 10 insertions, 2 deletions

diff --git a/lld/lib/ReaderWriter/ELF/ARM/ARMLinkingContext.h b/lld/lib/ReaderWriter/ELF/ARM/ARMLinkingContext.h
index 0c33e881fdd..f687713b25b 100644
--- a/lld/lib/ReaderWriter/ELF/ARM/ARMLinkingContext.h
+++ b/lld/lib/ReaderWriter/ELF/ARM/ARMLinkingContext.h
@@ -38,6 +38,7 @@ public:
       return false;
     assert(r.kindArch() == Reference::KindArch::ARM);
     switch (r.kindValue()) {
+    case llvm::ELF::R_ARM_GLOB_DAT:
     case llvm::ELF::R_ARM_TLS_TPOFF32:
     case llvm::ELF::R_ARM_COPY:
       return true;
diff --git a/lld/lib/ReaderWriter/ELF/ARM/ARMRelocationHandler.cpp b/lld/lib/ReaderWriter/ELF/ARM/ARMRelocationHandler.cpp
index e16379f631f..5142d4b80a9 100644
--- a/lld/lib/ReaderWriter/ELF/ARM/ARMRelocationHandler.cpp
+++ b/lld/lib/ReaderWriter/ELF/ARM/ARMRelocationHandler.cpp
@@ -665,6 +665,7 @@ std::error_code ARMTargetRelocationHandler::applyRelocation(
   case R_ARM_LDR_PC_G2:
     return relocR_ARM_LDR_PC_G2(loc, reloc, target, addend);
   case R_ARM_JUMP_SLOT:
+  case R_ARM_GLOB_DAT:
   case R_ARM_IRELATIVE:
     // Runtime only relocations. Ignore here.
     return std::error_code();
diff --git a/lld/lib/ReaderWriter/ELF/ARM/ARMRelocationPass.cpp b/lld/lib/ReaderWriter/ELF/ARM/ARMRelocationPass.cpp
index 7a95362d77e..517e201b4cd 100644
--- a/lld/lib/ReaderWriter/ELF/ARM/ARMRelocationPass.cpp
+++ b/lld/lib/ReaderWriter/ELF/ARM/ARMRelocationPass.cpp
@@ -945,9 +945,15 @@ public:
     return _plt0;
   }
 
+  const GOTAtom *getSharedGOTEntry(const SharedLibraryAtom *sla) {
+    return getGOT<R_ARM_GLOB_DAT>(sla);
+  }
+
   std::error_code handleGOT(const Reference &ref) {
-    assert(!isa<const SharedLibraryAtom>(ref.target()) &&
-           "Shared GOT entries aren't handled yet");
+    if (const auto sla = dyn_cast<const SharedLibraryAtom>(ref.target())) {
+      const_cast<Reference &>(ref).setTarget(getSharedGOTEntry(sla));
+      return std::error_code();
+    }
     return ARMRelocationPass::handleGOT(ref);
   }
 };