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Re: i386/asm-4 test: use amd64's natural addressing mode on all OSs


On Aug 15, 2019, Uros Bizjak <ubizjak@gmail.com> wrote:

> The immediate of lea is limited to +-2GB

... and we're talking about a code offset within a tiny translation
unit, with both reference and referenced address within the same
section.  It would be very surprising if the offset got up to 2KB, let
alone 2GB ;-)

The reason the testcase even mentions absolute addresses AFAICT is not
that it wishes to use them, it's that there's no portable way to use
PC-relative addresses on IA-32 (*), so the test gives up on platforms
that mandate PIC and goes with absolute addressing there.  I'm pretty
sure if it had a choice it would happily use PC-relative addressing,
even with a reasonably short range, if that was readily available...

(*) Something like 'call 1f; 1: popl %0; leal $foo-1b(%0), %0' is the
closest to widely available I'm aware of, but the '1f/1b' notation is
only available with GNU as AFAIK.

-- 
Alexandre Oliva, freedom fighter  he/him   https://FSFLA.org/blogs/lxo
Be the change, be Free!                 FSF Latin America board member
GNU Toolchain Engineer                        Free Software Evangelist
Hay que enGNUrecerse, pero sin perder la terGNUra jamás - Che GNUevara


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