Date: Thu, 15 Oct 2015 10:20:39 +0300 From: Konstantin Belousov <kostikbel@gmail.com> To: Garrett Cooper <ngie@FreeBSD.org> Cc: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: Re: svn commit: r289332 - head/tools/regression/lib/msun Message-ID: <20151015072039.GY2257@kib.kiev.ua> In-Reply-To: <201510142022.t9EKMC1C088993@repo.freebsd.org> References: <201510142022.t9EKMC1C088993@repo.freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, Oct 14, 2015 at 08:22:12PM +0000, Garrett Cooper wrote: > Author: ngie > Date: Wed Oct 14 20:22:12 2015 > New Revision: 289332 > URL: https://svnweb.freebsd.org/changeset/base/289332 > > Log: > Fix test-fenv:test_dfl_env when run on some amd64 CPUs > > Compare the fields that the AMD [1] and Intel [2] specs say will be > set once fnstenv returns. > > Not all amd64 capable processors zero out the env.__x87.__other field > (example: AMD Opteron 6308). The AMD64/x64 specs aren't explicit on what the > env.__x87.__other field will contain after fnstenv is executed, so the values > in env.__x87.__other could be filled with arbitrary data depending on how the > CPU-specific implementation of fnstenv. No Intel or AMD CPU write to __other field at all. > > 1. http://support.amd.com/TechDocs/26569_APM_v5.pdf > 2. http://www.intel.com/Assets/en_US/PDF/manual/253666.pdf > > Discussed with: kib, Anton Rang <anton.rang@isilon.com> > Reviewed by: Daniel O'Connor <darius@dons.net.au> (earlier patch; pre-generalization) > MFC after: 1 week > Sponsored by: EMC / Isilon Storage Division > Reported by: Bill Morchin <wmorchin@isilon.com> > > Modified: > head/tools/regression/lib/msun/test-fenv.c > > Modified: head/tools/regression/lib/msun/test-fenv.c > ============================================================================== > --- head/tools/regression/lib/msun/test-fenv.c Wed Oct 14 19:30:04 2015 (r289331) > +++ head/tools/regression/lib/msun/test-fenv.c Wed Oct 14 20:22:12 2015 (r289332) > @@ -133,8 +133,35 @@ test_dfl_env(void) > fenv_t env; > > fegetenv(&env); > + > +#ifdef __amd64__ > + /* > + * Compare the fields that the AMD [1] and Intel [2] specs say will be > + * set once fnstenv returns. > + * > + * Not all amd64 capable processors implement the fnstenv instruction > + * by zero'ing out the env.__x87.__other field (example: AMD Opteron > + * 6308). The AMD64/x64 specs aren't explicit on what the > + * env.__x87.__other field will contain after fnstenv is executed, so > + * the values in env.__x87.__other could be filled with arbitrary > + * data depending on how the CPU implements fnstenv. > + * > + * 1. http://support.amd.com/TechDocs/26569_APM_v5.pdf > + * 2. http://www.intel.com/Assets/en_US/PDF/manual/253666.pdf > + */ > + assert(memcmp(&env.__mxcsr, &FE_DFL_ENV->__mxcsr, > + sizeof(env.__mxcsr)) == 0); > + assert(memcmp(&env.__x87.__control, &FE_DFL_ENV->__x87.__control, > + sizeof(env.__x87.__control)) == 0); > + assert(memcmp(&env.__x87.__status, &FE_DFL_ENV->__x87.__status, > + sizeof(env.__x87.__status)) == 0); > + assert(memcmp(&env.__x87.__tag, &FE_DFL_ENV->__x87.__tag, > + sizeof(env.__x87.__tag)) == 0); > +#else > assert(memcmp(&env, FE_DFL_ENV, sizeof(env)) == 0); > #endif > + > +#endif > assert(fetestexcept(FE_ALL_EXCEPT) == 0); > } >
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20151015072039.GY2257>