On Thu, Mar 12, 2015 at 05:24:00PM -0700, enh wrote: > On Thu, Mar 12, 2015 at 4:18 PM, Rich Felker <dal...@libc.org> wrote: > > On Thu, Mar 12, 2015 at 03:12:18PM -0700, enh wrote: > >> https://android-review.googlesource.com/#/c/128430/ > >> > >> On Thu, Mar 12, 2015 at 3:10 PM, Rich Felker <dal...@libc.org> wrote: > >> > On Thu, Mar 12, 2015 at 03:07:39PM -0700, enh wrote: > >> >> there's a tool in Android that packs relative relocations. saves > >> >> several MiB on the chromium webview .so. long term we'd like to see > >> >> gold support it directly, but in the meantime it's a post-processing > >> >> phase. > >> > > >> > What kind of packing are you doing? > > > > OK, so it's via customization of the loader to process a different > > form of relocations. This seems dubious to me -- if the number of > > relocations is so large that it makes a practical difference to the > > file size, then you also have a large number of dirty pages that are > > wasting memory at runtime. Fixing the need for so many relative > > relocations, which are presumably a result of unnecessary and harmful > > global state containing pointers to functions or to other global > > state, seems like it would be a much more beneficial approach than > > packing the relocations. > > no one ever argued that chromium was svelte. but picking off 10% > mechanically is a lot easier than rewriting all the code.
I just see it a bit differently -- shaving off some portion of the relative relocations in chromium itself is a local change that's a strict improvement, but hacking the ELF format to pack relative relocations is a tradeoff -- a change that affects many different tools and has permanent maintenance cost for all of them. > the fact that this only affects LP64 makes me think it's not as simple > as that anyway, but afaik no one's looked into that. aarch64 is > especially bad. Yes, that seems really suspicious -- perhaps it's a toolchain bug that's generating all those relocations to begin with. Rich _______________________________________________ Toybox mailing list Toybox@lists.landley.net http://lists.landley.net/listinfo.cgi/toybox-landley.net