Add x86-specific checks.
Add x86-specific checks.

(Logical change 1.233)

android-ia/platform_external_libunwind,olibc/libunwind,android-ia/platform_external_libunwind,jrmuizel/libunwind,frida/libunwind,wdv4758h/libunwind,Keno/libunwind,libunwind/libunwind,fillexen/libunwind,unkadoug/libunwind,dagar/libunwind,vtjnash/libunwind,evaautomation/libunwind,dagar/libunwind,dagar/libunwind,vegard/libunwind,tkelman/libunwind,djwatson/libunwind,dreal-deps/libunwind,geekboxzone/mmallow_external_libunwind,fdoray/libunwind,adsharma/libunwind,project-zerus/libunwind,mpercy/libunwind,evaautomation/libunwind,igprof/libunwind,olibc/libunwind,ehsan/libunwind,zeldin/platform_external_libunwind,krytarowski/libunwind,dropbox/libunwind,yuyichao/libunwind,libunwind/libunwind,jrmuizel/libunwind,rogwfu/libunwind,Keno/libunwind,adsharma/libunwind,zeldin/platform_external_libunwind,geekboxzone/mmallow_external_libunwind,lat/libunwind,evaautomation/libunwind,android-ia/platform_external_libunwind,SyndicateRogue/libunwind,geekboxzone/lollipop_external_libunwind,djwatson/libunwind,lat/libunwind,fdoray/libunwind,tony/libunwind,yuyichao/libunwind,vegard/libunwind,krytarowski/libunwind,CyanogenMod/android_external_libunwind,rntz/libunwind,DroidSim/platform_external_libunwind,ehsan/libunwind,adsharma/libunwind,dropbox/libunwind,djwatson/libunwind,joyent/libunwind,joyent/libunwind,tony/libunwind,Chilledheart/libunwind,CyanogenMod/android_external_libunwind,yuyichao/libunwind,tronical/libunwind,igprof/libunwind,lat/libunwind,Keno/libunwind,atanasyan/libunwind,dropbox/libunwind,cloudius-systems/libunwind,Chilledheart/libunwind,mpercy/libunwind,rantala/libunwind,fdoray/libunwind,rantala/libunwind,wdv4758h/libunwind,rogwfu/libunwind,dreal-deps/libunwind,bo-on-software/libunwind,martyone/libunwind,cloudius-systems/libunwind,unkadoug/libunwind,pathscale/libunwind,DroidSim/platform_external_libunwind,0xlab/0xdroid-external_libunwind,cms-externals/libunwind,tony/libunwind,geekboxzone/lollipop_external_libunwind,ehsan/libunwind,libunwind/libunwind,atanasyan/libunwind-android,SyndicateRogue/libunwind,atanasyan/libunwind,atanasyan/libunwind-android,pathscale/libunwind,cms-externals/libunwind,project-zerus/libunwind,0xlab/0xdroid-external_libunwind,cms-externals/libunwind,frida/libunwind,tronical/libunwind,dreal-deps/libunwind,zeldin/platform_external_libunwind,atanasyan/libunwind,rantala/libunwind,igprof/libunwind,joyent/libunwind,CyanogenMod/android_external_libunwind,androidarmv6/android_external_libunwind,bo-on-software/libunwind,androidarmv6/android_external_libunwind,fillexen/libunwind,wdv4758h/libunwind,zliu2014/libunwind-tilegx,frida/libunwind,fillexen/libunwind,krytarowski/libunwind,Chilledheart/libunwind,rntz/libunwind,bo-on-software/libunwind,rogwfu/libunwind,DroidSim/platform_external_libunwind,androidarmv6/android_external_libunwind,zliu2014/libunwind-tilegx,mpercy/libunwind,maltek/platform_external_libunwind,tkelman/libunwind,cloudius-systems/libunwind,0xlab/0xdroid-external_libunwind,pathscale/libunwind,vtjnash/libunwind,vegard/libunwind,martyone/libunwind,martyone/libunwind,maltek/platform_external_libunwind,project-zerus/libunwind,olibc/libunwind,zliu2014/libunwind-tilegx,jrmuizel/libunwind,maltek/platform_external_libunwind,tkelman/libunwind,SyndicateRogue/libunwind,tronical/libunwind,atanasyan/libunwind-android,geekboxzone/lollipop_external_libunwind,rntz/libunwind,unkadoug/libunwind,vtjnash/libunwind,geekboxzone/mmallow_external_libunwind