diff options
Diffstat (limited to 'REORG.TODO/sysdeps/i386/fpu/fesetenv.c')
-rw-r--r-- | REORG.TODO/sysdeps/i386/fpu/fesetenv.c | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/i386/fpu/fesetenv.c b/REORG.TODO/sysdeps/i386/fpu/fesetenv.c new file mode 100644 index 0000000000..a338e5d555 --- /dev/null +++ b/REORG.TODO/sysdeps/i386/fpu/fesetenv.c @@ -0,0 +1,131 @@ +/* Install given floating-point environment. + Copyright (C) 1997-2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. + + 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 + <http://www.gnu.org/licenses/>. */ + +#include <fenv.h> +#include <fpu_control.h> +#include <assert.h> +#include <unistd.h> +#include <ldsodefs.h> +#include <dl-procinfo.h> + + +/* All exceptions, including the x86-specific "denormal operand" + exception. */ +#define FE_ALL_EXCEPT_X86 (FE_ALL_EXCEPT | __FE_DENORM) + + +int +__fesetenv (const fenv_t *envp) +{ + fenv_t temp; + + /* The memory block used by fstenv/fldenv has a size of 28 bytes. */ + assert (sizeof (fenv_t) == 28); + + /* Install the environment specified by ENVP. But there are a few + values which we do not want to come from the saved environment. + Therefore, we get the current environment and replace the values + we want to use from the environment specified by the parameter. */ + __asm__ ("fnstenv %0" : "=m" (*&temp)); + + if (envp == FE_DFL_ENV) + { + temp.__control_word |= FE_ALL_EXCEPT_X86; + temp.__control_word &= ~FE_TOWARDZERO; + temp.__control_word |= _FPU_EXTENDED; + temp.__status_word &= ~FE_ALL_EXCEPT_X86; + } + else if (envp == FE_NOMASK_ENV) + { + temp.__control_word &= ~(FE_ALL_EXCEPT | FE_TOWARDZERO); + /* Keep the "denormal operand" exception masked. */ + temp.__control_word |= __FE_DENORM; + temp.__control_word |= _FPU_EXTENDED; + temp.__status_word &= ~FE_ALL_EXCEPT_X86; + } + else + { + temp.__control_word &= ~(FE_ALL_EXCEPT_X86 + | FE_TOWARDZERO + | _FPU_EXTENDED); + temp.__control_word |= (envp->__control_word + & (FE_ALL_EXCEPT_X86 + | FE_TOWARDZERO + | _FPU_EXTENDED)); + temp.__status_word &= ~FE_ALL_EXCEPT_X86; + temp.__status_word |= envp->__status_word & FE_ALL_EXCEPT_X86; + } + temp.__eip = 0; + temp.__cs_selector = 0; + temp.__opcode = 0; + temp.__data_offset = 0; + temp.__data_selector = 0; + + __asm__ ("fldenv %0" : : "m" (temp)); + + if (HAS_CPU_FEATURE (SSE)) + { + unsigned int mxcsr; + __asm__ ("stmxcsr %0" : "=m" (mxcsr)); + + if (envp == FE_DFL_ENV) + { + /* Clear SSE exceptions. */ + mxcsr &= ~FE_ALL_EXCEPT_X86; + /* Set mask for SSE MXCSR. */ + mxcsr |= (FE_ALL_EXCEPT_X86 << 7); + /* Set rounding to FE_TONEAREST. */ + mxcsr &= ~0x6000; + mxcsr |= (FE_TONEAREST << 3); + /* Clear the FZ and DAZ bits. */ + mxcsr &= ~0x8040; + } + else if (envp == FE_NOMASK_ENV) + { + /* Clear SSE exceptions. */ + mxcsr &= ~FE_ALL_EXCEPT_X86; + /* Do not mask exceptions. */ + mxcsr &= ~(FE_ALL_EXCEPT << 7); + /* Keep the "denormal operand" exception masked. */ + mxcsr |= (__FE_DENORM << 7); + /* Set rounding to FE_TONEAREST. */ + mxcsr &= ~0x6000; + mxcsr |= (FE_TONEAREST << 3); + /* Clear the FZ and DAZ bits. */ + mxcsr &= ~0x8040; + } + else + mxcsr = envp->__eip; + + __asm__ ("ldmxcsr %0" : : "m" (mxcsr)); + } + + /* Success. */ + return 0; +} + +#include <shlib-compat.h> +#if SHLIB_COMPAT (libm, GLIBC_2_1, GLIBC_2_2) +strong_alias (__fesetenv, __old_fesetenv) +compat_symbol (libm, __old_fesetenv, fesetenv, GLIBC_2_1); +#endif + +libm_hidden_def (__fesetenv) +libm_hidden_ver (__fesetenv, fesetenv) +versioned_symbol (libm, __fesetenv, fesetenv, GLIBC_2_2); |