From 0b9af583a5c2d68085e88cece13952bf05dc4882 Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Wed, 28 Oct 2015 18:50:20 +0000 Subject: Fix i386/x86_64 fesetenv SSE exception clearing (bug 19181). The i386 and x86_64 versions of fesetenv, when called with FE_DFL_ENV or FE_NOMASK_ENV as argument, do not clear SSE exceptions raised in MXCSR. These arguments should, like other fenv_t values, represent the whole of the floating-point state, so such exceptions should be cleared; this patch adds the required clearing. (Discovered while working on bug 16068.) Tested for x86_64 and x86. [BZ #19181] * sysdeps/i386/fpu/fesetenv.c (__fesetenv): Clear already-raised SSE exceptions when argument is FE_DFL_ENV or FE_NOMASK_ENV. * sysdeps/x86_64/fpu/fesetenv.c (__fesetenv): Likewise. * math/test-fenv-clear-main.c: New file. * math/test-fenv-clear.c: Likewise. * math/Makefile (tests): Add test-fenv-clear. * sysdeps/x86/fpu/test-fenv-clear-sse.c: New file. * sysdeps/x86/fpu/Makefile [$(subdir) = math] (tests): Add test-fenv-clear-sse. [$(subdir) = math] (CFLAGS-test-fenv-clear-sse.c): New variable. --- sysdeps/i386/fpu/fesetenv.c | 4 ++++ sysdeps/x86/fpu/Makefile | 3 ++- sysdeps/x86/fpu/test-fenv-clear-sse.c | 45 +++++++++++++++++++++++++++++++++++ sysdeps/x86_64/fpu/fesetenv.c | 4 ++++ 4 files changed, 55 insertions(+), 1 deletion(-) create mode 100644 sysdeps/x86/fpu/test-fenv-clear-sse.c (limited to 'sysdeps') diff --git a/sysdeps/i386/fpu/fesetenv.c b/sysdeps/i386/fpu/fesetenv.c index 9566e092ca..910aa0991c 100644 --- a/sysdeps/i386/fpu/fesetenv.c +++ b/sysdeps/i386/fpu/fesetenv.c @@ -72,6 +72,8 @@ __fesetenv (const fenv_t *envp) if (envp == FE_DFL_ENV) { + /* Clear SSE exceptions. */ + mxcsr &= ~FE_ALL_EXCEPT; /* Set mask for SSE MXCSR. */ mxcsr |= (FE_ALL_EXCEPT << 7); /* Set rounding to FE_TONEAREST. */ @@ -80,6 +82,8 @@ __fesetenv (const fenv_t *envp) } else if (envp == FE_NOMASK_ENV) { + /* Clear SSE exceptions. */ + mxcsr &= ~FE_ALL_EXCEPT; /* Do not mask exceptions. */ mxcsr &= ~(FE_ALL_EXCEPT << 7); /* Set rounding to FE_TONEAREST. */ diff --git a/sysdeps/x86/fpu/Makefile b/sysdeps/x86/fpu/Makefile index 9cb7bb2d85..d38497cff3 100644 --- a/sysdeps/x86/fpu/Makefile +++ b/sysdeps/x86/fpu/Makefile @@ -1,5 +1,6 @@ ifeq ($(subdir),math) libm-support += powl_helper -tests += test-fenv-sse +tests += test-fenv-sse test-fenv-clear-sse CFLAGS-test-fenv-sse.c += -msse2 -mfpmath=sse +CFLAGS-test-fenv-clear-sse.c += -msse2 -mfpmath=sse endif diff --git a/sysdeps/x86/fpu/test-fenv-clear-sse.c b/sysdeps/x86/fpu/test-fenv-clear-sse.c new file mode 100644 index 0000000000..531164c79c --- /dev/null +++ b/sysdeps/x86/fpu/test-fenv-clear-sse.c @@ -0,0 +1,45 @@ +/* Test fesetenv (FE_DFL_ENV) and fesetenv (FE_NOMASK_ENV) clear + exceptions (bug 19181). SSE version. + Copyright (C) 2015 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include + +static bool +have_sse2 (void) +{ + unsigned int eax, ebx, ecx, edx; + + if (!__get_cpuid (1, &eax, &ebx, &ecx, &edx)) + return false; + + return (edx & bit_SSE2) != 0; +} + +#define CHECK_CAN_TEST \ + do \ + { \ + if (!have_sse2 ()) \ + { \ + puts ("CPU does not support SSE2, cannot test"); \ + return 0; \ + } \ + } \ + while (0) + +#include diff --git a/sysdeps/x86_64/fpu/fesetenv.c b/sysdeps/x86_64/fpu/fesetenv.c index 3e3fd8492d..9950aa734a 100644 --- a/sysdeps/x86_64/fpu/fesetenv.c +++ b/sysdeps/x86_64/fpu/fesetenv.c @@ -42,6 +42,8 @@ __fesetenv (const fenv_t *envp) temp.__opcode = 0; temp.__data_offset = 0; temp.__data_selector = 0; + /* Clear SSE exceptions. */ + temp.__mxcsr &= ~FE_ALL_EXCEPT; /* Set mask for SSE MXCSR. */ temp.__mxcsr |= (FE_ALL_EXCEPT << 7); /* Set rounding to FE_TONEAREST. */ @@ -57,6 +59,8 @@ __fesetenv (const fenv_t *envp) temp.__opcode = 0; temp.__data_offset = 0; temp.__data_selector = 0; + /* Clear SSE exceptions. */ + temp.__mxcsr &= ~FE_ALL_EXCEPT; /* Set mask for SSE MXCSR. */ /* Set rounding to FE_TONEAREST. */ temp.__mxcsr &= ~ 0x6000; -- cgit 1.4.1