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Re: [patch] Use a std::vector instead of a std::map to hold Input_merge_map

>>>> A std::map is hardly the best data structure for a small map from
>>>> small integers.
>>>> The attached patch uses a std::vector<std::pair>> instead.
>>>> This simplifies the code and speeds up linking of chromium (see
>>>> attached perf logs).

Yes, it seems like the original assumption that object files would
rarely have more than 2 merge sections is outdated.

Out of curiosity, did you try using an Unordered_map instead of
std::map? (While also removing first_map_ and second_map_.) I wonder
where the break-even point is between using a hash map and a linear

> 2015-04-23  Rafael Ãvila de EspÃndola <>
>         * (get_input_merge_map): Update for data structure change.
>           (get_or_make_input_merge_map): Update for data structure change.
>         * merge.h (Object_merge_map): Use a std::vector<std::pair>> instead of
>           a std::map.

Please add a note in the ChangeLog entry about removing first_shnum_, etc.

This is OK. Thanks!


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