On 21 May 2012 18:55, Vincent Diepeveen wrote: > hi, > > Kernel 3.4 supports X32 ABI. > > see > http://kernelnewbies.org/Linux_3.4#head-039c9d273884c9639937c10d68b4a3214869eb4b > > This could give fantastic speedups at x64 hardware as it combines the > advantages of 64 bits > programming, bunch of registers, with the advantage of still reusing the > old codes 'signed integer' lookup > which right now slows down so much in x64 as it creates an extra sign > extension for the lookup 32 bits signed > value to 64 bits signed value. > > Does GCC already support this and if so which options can i trigger this > with GCC? > > If so does this work at all x64 processors as well? > > If i google i see a few postings about X32 'backported to GCC' attempt in > 2011 somewhere, but no confirmation whatsoever. Google harder :) If I search for x32 gc the top hit is the x32 project homepage which says "X32 is functional complete with C, C++, Objective C and Fortran on GCC trunk as of revision 177914" The manual for GCC 4.7 documents the -mx32 switch at http://gcc.gnu.org/onlinedocs/gcc-4.7.0/gcc/i386-and-x86_002d64-Options.html
