[llvm-branch-commits] [llvm-objdump] -r: support CREL (PR #97382)

[James Henderson via llvm-branch-commits]

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@@ -1022,6 +1033,47 @@ ELFObjectFile<ELFT>::section_rel_begin(DataRefImpl Sec) const {
   uintptr_t SHT = reinterpret_cast<uintptr_t>((*SectionsOrErr).begin());
   RelData.d.a = (Sec.p - SHT) / EF.getHeader().e_shentsize;
   RelData.d.b = 0;
+  if (reinterpret_cast<const Elf_Shdr *>(Sec.p)->sh_type == ELF::SHT_CREL) {
+    if (RelData.d.a + 1 > Crels.size()) {
+      Crels.resize(RelData.d.a + 1);
+      CrelErrs.resize(RelData.d.a + 1);
+    }
+    if (Crels[RelData.d.a].empty()) {
+      // Decode SHT_CREL. See ELFFile<ELFT>::decodeCrel.
+      ArrayRef<uint8_t> Content = cantFail(getSectionContents(Sec));
+      DataExtractor Data(Content, ELFT::Endianness == endianness::little,
+                         sizeof(typename ELFT::Addr));
+      DataExtractor::Cursor Cur(0);
+      const uint64_t Hdr = Data.getULEB128(Cur);
+      const size_t Count = Hdr / 8;
+      const size_t FlagBits = Hdr & ELF::CREL_HDR_ADDEND ? 3 : 2;
+      const size_t Shift = Hdr % ELF::CREL_HDR_ADDEND;
+      uintX_t Offset = 0, Addend = 0;
+      uint32_t Symidx = 0, Type = 0;
+      for (size_t i = 0; i != Count; ++i) {
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jh7370 wrote:

It really doesn't feel right that this whole algorithm is duplicated from the version in ELF.cpp. Surely they can be folded together into shared code somewhere?

https://github.com/llvm/llvm-project/pull/97382