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-rw-r--r--REORG.TODO/sysdeps/i386/fpu/fesetenv.c131
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);