On Mon, Aug 13, 2012 at 5:59 AM, Uros Bizjak <ubiz...@gmail.com> wrote: > On Mon, Aug 13, 2012 at 2:10 PM, Jakub Jelinek <ja...@redhat.com> wrote: > >>> > To get the prefetchw cpuid flag, cpuid >>> > function 0x80000001 needs to be called. >>> > Previous to patch, function 0x7 is called. >>> > >>> > Bootstrapping and "make -k check" passes without failures. >>> > Ok for trunk? >>> >>> IMHO you move it to a wrong spot, ecx bits of CPUID 0x80000001 are tested >>> earlier. >>> >>> So I think you want this instead (bootstrap/regtest in progress): >>> >>> 2012-08-13 Ganesh Gopalasubramanian <ganesh.gopalasubraman...@amd.com> >>> Jakub Jelinek <ja...@redhat.com> >>> >>> PR driver/54210 >>> * config/i386/driver-i386.c (host_detect_local_cpu): Test bit_PRFCHW >>> bit of CPUID 0x80000001 %ecx instead of CPUID 7 %ecx. >>> * config/i386/cpuid.h (bits_PRFCHW): Move definition to CPUID >>> 0x80000001 %ecx flags. >> >> Now bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? > > OK, but I didn't find PRFCHW in the cpuid documentation to confirm the change. > > Thanks, > Uros.
It is in Intel AVX spec: http://software.intel.com/en-us/avx/ -- H.J.
