On 12/9/22 17:26, Michal Suchánek wrote:
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.
Sure, some benefit will be there. But I doubt it's really measurable.
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.
Well, if you repackage 32-bit binaries into x86_64, you're not going to install them on a pure 32-bit system are you?
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.
I wasn't seriously suggesting that. I was just confused by Bruno's suggestion as I have never seen the approach of using -march=x86-64 together with -m32. As I said, I'm more a fan of the MultiArch approach as it avoids the whole effort of repackaging 32-bit binaries into x86-64 RPM packages. You can just install the 32-bit packages from the 32-bit distribution on a 64-bit system. Adrian