[llvm] [llvm-objdump] Display RELR dynamic relocations (PR #224069)

[Tianyi Chen via llvm-commits]

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@@ -364,7 +364,23 @@ template <typename ELFT> void ELFDumper<ELFT>::printDynamicRelocations() {
          << left_justify("TYPE", TypePadding) << " VALUE\n";
 
   StringRef Fmt = Obj.getBytesInAddress() > 4 ? "%016" PRIx64 : "%08" PRIx64;
-  for (const SectionRef &Section : DynRelSec)
+  for (const SectionRef &Section : DynRelSec) {
+    if (ELFSectionRef(Section).getType() == ELF::SHT_RELR) {
+      const auto &Elf = getELFFile();
+      auto Relrs =
+          unwrapOrError(Elf.relrs(*Obj.getSection(Section.getRawDataRefImpl())),
+                        Obj.getFileName());
+      StringRef RelocName =
+          Elf.getRelocationTypeName(Elf.getRelativeRelocationType());
+      for (const auto &Rel : Elf.decode_relrs(Relrs)) {
+        uint64_t Address = Rel.r_offset;
+        // RELR has neither a symbol reference nor an explicit addend.
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chenty2333 wrote:

Thanks, agreed. RELR encodes the relocation locations, not explicit addends; the implicit addend lives at the relocated location. I have kept '-' rather than inferring an addend from the RELR entries.

https://github.com/llvm/llvm-project/pull/224069