[PATCH] D70658: [LLD][ELF] - Make compression level be dependent on -On.

[Rui Ueyama via Phabricator via llvm-commits]

ruiu added inline comments.


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Comment at: lld/ELF/OutputSections.cpp:273
   // Write section contents to a temporary buffer and compress it.
   std::vector<uint8_t> buf(size);
   writeTo<ELFT>(buf.data());
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It's worth adding a comment here to explain why we chose 6 and 1 as optimization levels. We chose 1 as the default compression level because it is the fastest. If -O2 is given, we use level 6 to compress debug info more by ~15%. We found that level 7 to 9 doesn't make much difference (~1% more compression) while they take significant amount of time (~2x), so level 6 seems enough.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D70658/new/

https://reviews.llvm.org/D70658