[PATCH, i386] Remove EBX usage from asm code

Jakub Jelinek jakub@redhat.com
Mon Jan 12 10:54:00 GMT 2015


On Mon, Jan 12, 2015 at 01:36:05PM +0300, Evgeny Stupachenko wrote:
> "frame_dummy" does not use EBX in allocation now as there are enough
> other registers (that we don't need to save/restore). So if we do not
> modify "frame_dummy" EBX should stay unchanged.
> "frame_dummy" does not initialize EBX register at the beginning it
> expects that EBX is pic from glibc
> "frame_dummy" is called from glibc and while we have glibc compiled by
> 4.9 or older compiler EBX should come to "frame_dummy" as pic register

I also don't understand how is this related to glibc in any way.
>From my understanding, the macro relied on %ebx being set to
_GLOBAL_OFFSET_TABLE_ because the frame_dummy function does access
GOT, so before the i?86 PIC reg changes it was computing %ebx.

	Jakub



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