On Fri, Dec 09, 2022 at 04:46:20PM +0100, John Paul Adrian Glaubitz wrote:
On 12/9/22 15:44, Bruno Pitrus wrote:
You're confusing things. I know what x32 is and nobody cares about supporting it. (There was an aborted effort at porting Tumbleweed to the ARM equivalent of x32, fwiw)
Sure, it's still supported in Debian and Gentoo :-).
`file` is not going to tell you what instructions an executable contains, it only looks at the elf header. Try to compile an executable which runs a more complicated algorithm (copying an array of a dozen elements should suffice) with -march=i586 and x86-64. if you examine them in objdump, the second should contain SSE instructions.
I understand what you mean now. But I'm not sure whether the x86-64 baseline with the limited set of registers on i386 will bring you any remarkable benefit.
Hard to tell without measurements. Still SSE does give you extra registers so it should help especially for 32bit where the base registers are limited. Nonetheless, we *do* intend to still provide a 32bit port, and unless the 32bit libraries are to be built twice they should be built for the 32bit architecture we provide as the LegacyX86 port.
After all, x32 was created to be able to really profit from x86-64 features on a 32-bit target.
But the 32bit libraries are in part for support of legacy binaries and changing the ABI is not going to work for that. Thanks Michal