[lld] [LLD][COFF] Implement ARM64X relocations for the exception table (PR #123723)

[Martin Storsjö via llvm-commits]

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@@ -1230,6 +1230,16 @@ void DynamicRelocsChunk::finalize() {
   size = alignTo(size, sizeof(uint32_t));
 }
 
+// Set the reloc value. The reloc entry must be allocated beforehand.
+void DynamicRelocsChunk::set(uint32_t rva, Arm64XRelocVal value) {
+  Arm64XDynamicRelocEntry &entry =
+      *llvm::find_if(arm64xRelocs, [rva](const Arm64XDynamicRelocEntry &e) {
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mstorsjo wrote:

I guess this assumes that this does find an entry. If it doesn't, does it trigger UB or something else - can we receive the returned iterator(?) and check it with an assert, before dereferencing it?

https://github.com/llvm/llvm-project/pull/123723