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[clang] Increase the bitness of data length in ASTDeclContextNameLookup
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Authored by danlark on Feb 18 2021, 2:53 PM.

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rsmith
Summary

We faced the assert of too many declarations for serialized lookup for a very huge generated C++ target. We
think moving the type to uint32_t helps us. As I am not sure in the fix, please validate the correctness.

I don't have commit rights. Email: danilak@google.com. Name: Danila Kutenin.

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danlark requested review of this revision.Feb 18 2021, 2:53 PM
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danlark edited the summary of this revision. (Show Details)Feb 18 2021, 2:57 PM

Thanks for the diagnosis and the patch!

We spend a significant amount of our AST file size on these lookup tables, so I think the extra two bytes per lookup entry is best avoided if possible. We also have the same problem for other on-disk hash tables. I went ahead and generalized this to cover all of our on-disk hash tables and switched from fixed-width to variable-width encoding in rGe0589d70fb8e29842fab228df716f73b378710a6.

danlark abandoned this revision.Feb 19 2021, 12:17 AM

Thanks!