[lld] [LLD][COFF] Add basic ARM64X dynamic relocations support (PR #118035)

[Martin Storsjö via llvm-commits]

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@@ -2555,6 +2566,33 @@ void Writer::addBaserelBlocks(std::vector<Baserel> &v) {
   relocSec->addChunk(make<BaserelChunk>(page, &v[i], &v[0] + j));
 }
 
+void Writer::createDynamicRelocs() {
+  if (!ctx.dynamicRelocs)
+    return;
+
+  const uint32_t coffHeaderOffset = dosStubSize + sizeof(PEMagic);
+  const uint32_t peHeaderOffset = coffHeaderOffset + sizeof(coff_file_header);
+  const uint32_t dataDirOffset = peHeaderOffset + sizeof(pe32plus_header);
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mstorsjo wrote:

Oh, skipping the DOS stub for ARM targets sounds like a nice cleanup that we probably could/should do as well. Then it's indeed good to have such asserts in place to make sure that whatever changes we do (including making the offset runtime calculated), this stays in sync.

https://github.com/llvm/llvm-project/pull/118035