[PATCH] D62540: [SampleFDO] For functions without profiles, provide an option to put them in a special text section

[Wei Mi via Phabricator via llvm-commits]

wmi added a comment.

In D62540#1520129 <https://reviews.llvm.org/D62540#1520129>, @davidxl wrote:

> Why is symbol remapping an issue? old MD5 --> input symbol name -> output symbol name --> mapped MD5sum ?


We want to use profile remapping support when we want to find the counterparts in profile for the set of symbols being renamed during optimized build after a large scale codebase refactoring. The profile remapping support doesn't work well if the symbols in the profile are md5. If the symbol whitelist contain md5, after refactoring, profile remapping will not find old symbols being renamed in the whitelist and will think they are all new symbols.

Existing profile remapping doesn't support comparing old MD5 with the mapped MD5. profile remapping is based on C++ mangling, so only symbol names are supported during remapping.


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  rL LLVM

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  https://reviews.llvm.org/D62540/new/

https://reviews.llvm.org/D62540