On Mon, Jul 31, 2017 at 02:06:36PM -0400, Alain Toussaint wrote: > > I use linode. Why use an x32 ABI? I've done 64-bit builds there several > > times and the native system is 64-bit. > > > There is some key difference between i386, x32 and x64 ABI. i386 we > know it for quite a bit of time but in the case of x32 ABI, it uses > the full feature set of x86_64 with the exception of the pointers > being 32 bits instead of 64 bits; thus, the maximum memory for > applications is 4GB but it can still uses the 15 integer registers (6 > registers for i386), 16 FP registers (8 for i386) and SSE instead of > 80387 float. > > Application size are reported to be 20% smallers and about same speed > increases over both i386 code and 64 bits code (to be tested). > > sources: https://en.wikipedia.org/wiki/X32_ABI (useful summary) and > https://sites.google.com/site/x32abi/ (abi documentation is densely > packed with details, a rough read). >
At one time (probably 5+ years ago) I was thinking about trying x32 because I had an old x86_64 machine with 1GB DRAM (probably PC100, yes, it was that old). But at that time I got the impression that a lot of my normal desktop packages were not ready for x32. Since then, of course, that box has died. For the moment, 4GB machines are just-about adequate for building x86_64 so I haven't seen any reason to look at x32 again. ISTR that Vapier at gentoo was doing a lot on x32 and at one time had many patches for it. I've certainly seen some references to x32 when I've been looking at ebuilds, so I guess they will be a good place to start when things don't build. Of course, you need to start with real cross-compiling: something based on cross-lfs x86_64 (64-bit) is probably a good place to start, although you'll need to work out the details for yourself because they don't do x32). ĸen -- I live in a city. I know sparrows from starlings. After that everything is a duck as far as I'm concerned. -- Monstrous Regiment -- http://lists.linuxfromscratch.org/listinfo/lfs-dev FAQ: http://www.linuxfromscratch.org/faq/ Unsubscribe: See the above information page
