[llvm-branch-commits] [NFCI][ELF][AArch64][PAC] Teach addRelativeReloc to emit R_AARCH64_AUTH_RELATIVE (PR #171180)

[Jessica Clarke via llvm-branch-commits]

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@@ -704,8 +704,10 @@ static void addRelativeReloc(Ctx &ctx, InputSectionBase &isec,
                              uint64_t offsetInSec, Symbol &sym, int64_t addend,
                              RelExpr expr, RelType type) {
   Partition &part = isec.getPartition(ctx);
+  bool isAArch64Auth =
+      ctx.arg.emachine == EM_AARCH64 && type == R_AARCH64_AUTH_ABS64;
 
-  if (sym.isTagged()) {
+  if (sym.isTagged() && !isAArch64Auth) {
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jrtc27 wrote:

With PAuth2 XORing rather than replacing the upper bits you might even be able to do both for a given pointer? I haven’t properly thought it through and it may be a terrible idea, but on the surface it seemed plausible to me.

https://github.com/llvm/llvm-project/pull/171180