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Re: Reducing code size of Position Independent Executables (PIE) by shrinking the size of dynamic relocations section



On 2017.04.25 at 21:06 -0700, Cary Coutant wrote:
> > Idea A: Shrinking the size of the dynamic relocations
>
> In a RELATIVE relocation, the r_offset field is really the only field
> of interest. The symbol and addend are not used -- the dynamic loader
> simply adjusts the address at the given offset by the relocation
> factor for the load module. Thus, it truly is possible to reduce these
> relocations to just the one word.
>
> Simon Baldwin did a lot of work on this a few years ago for Chromium,
> writing a post-link utility to extract all the RELATIVE relocations
> and rewrite them to a new section.

FYI Mike Hommey did something similar for Firefox and wrote about here:
https://glandium.org/blog/?p=1177

--
Markus