[lld] [LLD, MachO] Add `getUnwindInfoEncodingHash` to `BPSectionOrderer.cpp`. (PR #105587)

[Ellis Hoag via llvm-commits]

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@@ -60,6 +61,25 @@ getRelocHash(const Reloc &reloc,
   return getRelocHash(kind, sectionIdx.value_or(0), 0, reloc.addend);
 }
 
+static uint64_t getUnwindInfoEncodingHash(const InputSection *isec) {
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ellishg wrote:

Can you add a quick comment explaining why adding this unwind info hash can improve uncompressed size?

https://github.com/llvm/llvm-project/pull/105587