Re: x32 psABI draft version 0.2

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Thu, Feb 17, 2011 at 7:22 AM, Jan Hubicka <hubicka@ucw.cz> wrote:
>> On Thu, Feb 17, 2011 at 08:35:26AM +0000, Jan Beulich wrote:
>> > >>> On 16.02.11 at 21:04, "H. Peter Anvin" <hpa@zytor.com> wrote:
>> > > On 02/16/2011 11:22 AM, H.J. Lu wrote:
>> > >> Hi,
>> > >>
>> > >> I updated ?x32 psABI draft to version 0.2 to change x32 library path
>> > >> from lib32 to libx32 since lib32 is used for ia32 libraries on Debian,
>> > >> Ubuntu and other derivative distributions. The new x32 psABI is
>> > >> available from:
>> > >>
>> > >> https://sites.google.com/site/x32abi/home
>> > >>
>> > >
>> > > I'm wondering if we should define a section header flag (sh_flags)
>> > > and/or an ELF header flag (e_flags) for x32 for the people unhappy about
>> > > keying it to the ELF class...
>> >
>> > Thanks for supporting this!
>> >
>> > Besides that I also wonder why all the 64-bit relocations get
>> > marked as LP64-only. It is clear that some of them can be useful
>> > in ILP32 as well, and there's no reason to preclude future uses
>> > even if currently no-one can imagine any.
>> >
>> > Furthermore, it seems questionable to continue to require rela
>> > relocations when for all normal ones (leaving aside the 8- and 16-
>> > bit ones) the addend can fit in the relocated field.
>>
>> REL is horrible pain, we shouldn't ever add new REL targets.
>
> According to Mozilla folks however REL+RELA scheme used by EABI leads
> to significandly smaller libxul.so size
>
> According to http://glandium.org/blog/?p=1177 the difference is about 4-5MB
> (out of approximately 20-30MB shared lib)

This is orthogonal to x32 psABI.



-- 
H.J.