From e01e7b4c3e21e97663e74d5262d5f61e9d3a5c41 Mon Sep 17 00:00:00 2001 From: ngie Date: Mon, 26 Oct 2015 00:07:11 +0000 Subject: [PATCH] MFstable/10 r289970: MFC r289332: 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. 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 Reviewed by: Daniel O'Connor (earlier patch; pre-generalization) Sponsored by: EMC / Isilon Storage Division Reported by: Bill Morchin git-svn-id: svn://svn.freebsd.org/base/stable/9@289971 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f --- tools/regression/lib/msun/test-fenv.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/tools/regression/lib/msun/test-fenv.c b/tools/regression/lib/msun/test-fenv.c index 71e8eedb3..0ea6e42a7 100644 --- a/tools/regression/lib/msun/test-fenv.c +++ b/tools/regression/lib/msun/test-fenv.c @@ -133,7 +133,34 @@ 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); } -- 2.45.0