- add C99 floating point environment, rounding and exception handling functions

  for i386. UCLIBC_HAS_FENV

Makefile.in

@@ -140,6 +140,11 @@ ifneq ($(UCLIBC_HAS_FLOATS),y)
 	$(RM) $(PREFIX)$(DEVEL_PREFIX)include/tgmath.h
 	$(RM) $(PREFIX)$(DEVEL_PREFIX)include/bits/uClibc_fpmax.h
 endif
+ifneq ($(UCLIBC_HAS_FENV),y)
+	$(RM) $(PREFIX)$(DEVEL_PREFIX)include/fenv.h \
+		$(PREFIX)$(DEVEL_PREFIX)include/bits/fenv.h \
+		$(PREFIX)$(DEVEL_PREFIX)include/bits/fenvinline.h
+endif
 ifneq ($(UCLIBC_HAS_WCHAR),y)
 	# Remove wide char headers since wide char support is disabled.
 	$(RM) $(PREFIX)$(DEVEL_PREFIX)include/wctype.h

extra/Configs/Config.in.arch

@@ -159,6 +159,15 @@ config DO_C99_MATH
 	  If your applications require the newer C99 math library functions, 
 	  then answer Y.
 
+config UCLIBC_HAS_FENV
+	bool "Enable C99 Floating-point environment"
+	depends on UCLIBC_HAS_FLOATS
+	default n
+	help
+	  If you want the uClibc math library to contain the C99 floating
+	  point environment, rounding and exception handling functions then
+	  say Y here.
+
 config KERNEL_HEADERS
 	string "Linux kernel header location"
 	default "/usr/include"

libm/i386/Makefile.arch

@@ -0,0 +1,24 @@
+# Makefile for uClibc
+#
+# Copyright (C) 2000-2008 Erik Andersen <andersen@uclibc.org>
+#
+# Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball.
+#
+# The routines included in this math library are derived from
+# glibc's libm.
+#
+
+ifeq ($(UCLIBC_HAS_FENV),y)
+libm_ARCH_SRC:=$(wildcard $(libm_ARCH_DIR)/*.c)
+libm_ARCH_OBJ:=$(patsubst $(libm_ARCH_DIR)/%.c,$(libm_ARCH_OUT)/%.o,$(libm_ARCH_SRC))
+endif
+
+libm_ARCH_OBJS:=$(libm_ARCH_OBJ)
+
+ifeq ($(DOPIC),y)
+libm-a-y+=$(libm_ARCH_OBJS:.o=.os)
+else
+libm-a-y+=$(libm_ARCH_OBJS)
+endif
+libm-so-y+=$(libm_ARCH_OBJS:.o=.os)
+

libm/i386/fclrexcpt.c

@@ -0,0 +1,61 @@
+/* Clear given exceptions in current floating-point environment.
+   Copyright (C) 1997,99,2000, 2001, 2003, 2004 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <fenv.h>
+#include <unistd.h>
+
+int
+feclearexcept (int excepts)
+{
+  fenv_t temp;
+
+  /* Mask out unsupported bits/exceptions.  */
+  excepts &= FE_ALL_EXCEPT;
+
+  /* Bah, we have to clear selected exceptions.  Since there is no
+     `fldsw' instruction we have to do it the hard way.  */
+  __asm__ ("fnstenv %0" : "=m" (*&temp));
+
+  /* Clear the relevant bits.  */
+  temp.__status_word &= excepts ^ FE_ALL_EXCEPT;
+
+  /* Put the new data in effect.  */
+  __asm__ ("fldenv %0" : : "m" (*&temp));
+
+#if 0
+  /* If the CPU supports SSE, we clear the MXCSR as well.  */
+  if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0)
+    {
+      unsigned int xnew_exc;
+
+      /* Get the current MXCSR.  */
+      __asm__ ("stmxcsr %0" : "=m" (*&xnew_exc));
+
+      /* Clear the relevant bits.  */
+      xnew_exc &= ~excepts;
+
+      /* Put the new data in effect.  */
+      __asm__ ("ldmxcsr %0" : : "m" (*&xnew_exc));
+    }
+#endif
+
+  /* Success.  */
+  return 0;
+}

libm/i386/fedisblxcpt.c

@@ -0,0 +1,55 @@
+/* Disable floating-point exceptions.
+   Copyright (C) 1999, 2000, 2003, 2004 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Andreas Jaeger <aj@suse.de>, 1999.
+
+   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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <fenv.h>
+#include <unistd.h>
+
+int
+fedisableexcept (int excepts)
+{
+  unsigned short int new_exc, old_exc;
+
+  /* Get the current control word.  */
+  __asm__ ("fstcw %0" : "=m" (*&new_exc));
+
+  old_exc = (~new_exc) & FE_ALL_EXCEPT;
+
+  excepts &= FE_ALL_EXCEPT;
+
+  new_exc |= excepts;
+  __asm__ ("fldcw %0" : : "m" (*&new_exc));
+
+#if 0
+  /* If the CPU supports SSE we set the MXCSR as well.  */
+  if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0)
+    {
+      unsigned int xnew_exc;
+
+      /* Get the current control word.  */
+      __asm__ ("stmxcsr %0" : "=m" (*&xnew_exc));
+
+      xnew_exc |= excepts << 7;
+
+      __asm__ ("ldmxcsr %0" : : "m" (*&xnew_exc));
+    }
+#endif
+
+  return old_exc;
+}

libm/i386/feenablxcpt.c

@@ -0,0 +1,55 @@
+/* Enable floating-point exceptions.
+   Copyright (C) 1999, 2000, 2003, 2004 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Andreas Jaeger <aj@suse.de>, 1999.
+
+   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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <fenv.h>
+#include <unistd.h>
+
+int
+feenableexcept (int excepts)
+{
+  unsigned short int new_exc;
+  unsigned short int old_exc;
+
+  /* Get the current control word.  */
+  __asm__ ("fstcw %0" : "=m" (*&new_exc));
+
+  excepts &= FE_ALL_EXCEPT;
+  old_exc = (~new_exc) & FE_ALL_EXCEPT;
+
+  new_exc &= ~excepts;
+  __asm__ ("fldcw %0" : : "m" (*&new_exc));
+
+#if 0
+  /* If the CPU supports SSE we set the MXCSR as well.  */
+  if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0)
+    {
+      unsigned int xnew_exc;
+
+      /* Get the current control word.  */
+      __asm__ ("stmxcsr %0" : "=m" (*&xnew_exc));
+
+      xnew_exc &= ~(excepts << 7);
+
+      __asm__ ("ldmxcsr %0" : : "m" (*&xnew_exc));
+    }
+#endif
+
+  return old_exc;
+}

libm/i386/fegetenv.c

@@ -0,0 +1,34 @@
+/* Store current floating-point environment.
+   Copyright (C) 1997,1999,2000,2001,2003 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <fenv.h>
+
+int
+fegetenv (fenv_t *envp)
+{
+  __asm__ ("fnstenv %0" : "=m" (*envp));
+  /* And load it right back since the processor changes the mask.
+     Intel thought this opcode to be used in interrupt handlers which
+     would block all exceptions.  */
+  __asm__ ("fldenv %0" : : "m" (*envp));
+
+  /* Success.  */
+  return 0;
+}

libm/i386/fegetexcept.c

@@ -0,0 +1,32 @@
+/* Get enabled floating-point exceptions.
+   Copyright (C) 1999, 2000 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Andreas Jaeger <aj@suse.de>, 1999.
+
+   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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <fenv.h>
+
+int
+fegetexcept (void)
+{
+  unsigned short int exc;
+
+  /* Get the current control word.  */
+  __asm__ ("fstcw %0" : "=m" (*&exc));
+
+  return (~exc) & FE_ALL_EXCEPT;
+}

libm/i386/fegetround.c

@@ -0,0 +1,31 @@
+/* Return current rounding direction.
+   Copyright (C) 1997 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <fenv.h>
+
+int
+fegetround (void)
+{
+  int cw;
+
+  __asm__ ("fnstcw %0" : "=m" (*&cw));
+
+  return cw & 0xc00;
+}

libm/i386/feholdexcpt.c

@@ -0,0 +1,59 @@
+/* Store current floating-point environment and clear exceptions.
+   Copyright (C) 1997, 1999, 2003, 2004, 2005, 2007
+   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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <fenv.h>
+#include <unistd.h>
+
+int
+feholdexcept (fenv_t *envp)
+{
+  fenv_t temp;
+
+  /* Store the environment.  */
+  __asm__ ("fnstenv %0" : "=m" (temp));
+  *envp = temp;
+
+  /* Now set all exceptions to non-stop.  */
+  temp.__control_word |= 0x3f;
+
+  /* And clear all exceptions.  */
+  temp.__status_word &= ~0x3f;
+
+  __asm__ ("fldenv %0" : : "m" (temp));
+
+#if 0
+  /* If the CPU supports SSE we set the MXCSR as well.  */
+  if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0)
+    {
+      unsigned int xwork;
+
+      /* Get the current control word.  */
+      __asm__ ("stmxcsr %0" : "=m" (*&xwork));
+
+      /* Set all exceptions to non-stop and clear them.  */
+      xwork = (xwork | 0x1f80) & ~0x3f;
+
+      __asm__ ("ldmxcsr %0" : : "m" (*&xwork));
+    }
+#endif
+
+  return 0;
+}

libm/i386/fesetenv.c

@@ -0,0 +1,80 @@
+/* Install given floating-point environment.
+   Copyright (C) 1997,98,99,2000,01,02 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <fenv.h>
+#include <assert.h>
+
+libm_hidden_proto(fesetenv)
+
+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;
+      temp.__control_word &= ~FE_TOWARDZERO;
+      temp.__status_word &= ~FE_ALL_EXCEPT;
+      temp.__eip = 0;
+      temp.__cs_selector = 0;
+      temp.__opcode = 0;
+      temp.__data_offset = 0;
+      temp.__data_selector = 0;
+    }
+  else if (envp == FE_NOMASK_ENV)
+    {
+      temp.__control_word &= ~(FE_ALL_EXCEPT | FE_TOWARDZERO);
+      temp.__status_word &= ~FE_ALL_EXCEPT;
+      temp.__eip = 0;
+      temp.__cs_selector = 0;
+      temp.__opcode = 0;
+      temp.__data_offset = 0;
+      temp.__data_selector = 0;
+    }
+  else
+    {
+      temp.__control_word &= ~(FE_ALL_EXCEPT | FE_TOWARDZERO);
+      temp.__control_word |= (envp->__control_word
+			      & (FE_ALL_EXCEPT | FE_TOWARDZERO));
+      temp.__status_word &= ~FE_ALL_EXCEPT;
+      temp.__status_word |= envp->__status_word & FE_ALL_EXCEPT;
+      temp.__eip = envp->__eip;
+      temp.__cs_selector = envp->__cs_selector;
+      temp.__opcode = envp->__opcode;
+      temp.__data_offset = envp->__data_offset;
+      temp.__data_selector = envp->__data_selector;
+    }
+
+  __asm__ ("fldenv %0" : : "m" (temp));
+
+  /* Success.  */
+  return 0;
+}
+libm_hidden_def(fesetenv)

libm/i386/fesetround.c

@@ -0,0 +1,52 @@
+/* Set current rounding direction.
+   Copyright (C) 1997, 2003, 2004, 2005 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <fenv.h>
+#include <unistd.h>
+
+int
+fesetround (int round)
+{
+  unsigned short int cw;
+
+  if ((round & ~0xc00) != 0)
+    /* ROUND is no valid rounding mode.  */
+    return 1;
+
+  __asm__ ("fnstcw %0" : "=m" (*&cw));
+  cw &= ~0xc00;
+  cw |= round;
+  __asm__ ("fldcw %0" : : "m" (*&cw));
+
+#if 0
+  /* If the CPU supports SSE we set the MXCSR as well.  */
+  if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0)
+    {
+      unsigned int xcw;
+
+      __asm__ ("stmxcsr %0" : "=m" (*&xcw));
+      xcw &= ~0x6000;
+      xcw |= round << 3;
+      __asm__ ("ldmxcsr %0" : : "m" (*&xcw));
+    }
+#endif
+
+  return 0;
+}

libm/i386/feupdateenv.c

@@ -0,0 +1,56 @@
+/* Install given floating-point environment and raise exceptions.
+   Copyright (C) 1997,99,2000,01,07 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <fenv.h>
+#include <unistd.h>
+
+libm_hidden_proto(fesetenv)
+libm_hidden_proto(feraiseexcept)
+
+int
+feupdateenv (const fenv_t *envp)
+{
+  fexcept_t temp;
+  /* unsigned int xtemp = 0; */
+
+  /* Save current exceptions.  */
+  __asm__ ("fnstsw %0" : "=m" (*&temp));
+
+#if 0
+  /* If the CPU supports SSE we test the MXCSR as well.  */
+  if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0)
+    __asm__ ("stmxcsr %0" : "=m" (*&xtemp));
+
+  temp = (temp | xtemp) & FE_ALL_EXCEPT;
+#else
+  temp &= FE_ALL_EXCEPT;
+#endif
+
+  /* Install new environment.  */
+  fesetenv (envp);
+
+  /* Raise the saved exception.  Incidently for us the implementation
+     defined format of the values in objects of type fexcept_t is the
+     same as the ones specified using the FE_* constants.  */
+  feraiseexcept ((int) temp);
+
+  /* Success.  */
+  return 0;
+}

libm/i386/fgetexcptflg.c

@@ -0,0 +1,35 @@
+/* Store current representation for exceptions.
+   Copyright (C) 1997,99,2000,01 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <fenv.h>
+
+int
+fegetexceptflag (fexcept_t *flagp, int excepts)
+{
+  fexcept_t temp;
+
+  /* Get the current exceptions.  */
+  __asm__ ("fnstsw %0" : "=m" (*&temp));
+
+  *flagp = temp & excepts & FE_ALL_EXCEPT;
+
+  /* Success.  */
+  return 0;
+}

libm/i386/fraiseexcpt.c

@@ -0,0 +1,118 @@
+/* Raise given exceptions.
+   Copyright (C) 1997,99,2000,01,02 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <fenv.h>
+#include <math.h>
+
+libm_hidden_proto(feraiseexcept)
+
+int
+feraiseexcept (int excepts)
+{
+  /* Raise exceptions represented by EXPECTS.  But we must raise only
+     one signal at a time.  It is important that if the overflow/underflow
+     exception and the inexact exception are given at the same time,
+     the overflow/underflow exception follows the inexact exception.  */
+
+  /* First: invalid exception.  */
+  if ((FE_INVALID & excepts) != 0)
+    {
+      /* One example of a invalid operation is 0.0 / 0.0.  */
+      double d;
+      __asm__ __volatile__ ("fldz; fdiv %%st, %%st(0); fwait" : "=t" (d));
+      (void) &d;
+    }
+
+  /* Next: division by zero.  */
+  if ((FE_DIVBYZERO & excepts) != 0)
+    {
+      double d;
+      __asm__ __volatile__ ("fldz; fld1; fdivp %%st, %%st(1); fwait"
+			    : "=t" (d));
+      (void) &d;
+    }
+
+  /* Next: overflow.  */
+  if ((FE_OVERFLOW & excepts) != 0)
+    {
+      /* There is no way to raise only the overflow flag.  Do it the
+	 hard way.  */
+      fenv_t temp;
+
+      /* Bah, we have to clear selected exceptions.  Since there is no
+	 `fldsw' instruction we have to do it the hard way.  */
+      __asm__ __volatile__ ("fnstenv %0" : "=m" (*&temp));
+
+      /* Set the relevant bits.  */
+      temp.__status_word |= FE_OVERFLOW;
+
+      /* Put the new data in effect.  */
+      __asm__ __volatile__ ("fldenv %0" : : "m" (*&temp));
+
+      /* And raise the exception.  */
+      __asm__ __volatile__ ("fwait");
+    }
+
+  /* Next: underflow.  */
+  if ((FE_UNDERFLOW & excepts) != 0)
+    {
+      /* There is no way to raise only the underflow flag.  Do it the
+	 hard way.  */
+      fenv_t temp;
+
+      /* Bah, we have to clear selected exceptions.  Since there is no
+	 `fldsw' instruction we have to do it the hard way.  */
+      __asm__ __volatile__ ("fnstenv %0" : "=m" (*&temp));
+
+      /* Set the relevant bits.  */
+      temp.__status_word |= FE_UNDERFLOW;
+
+      /* Put the new data in effect.  */
+      __asm__ __volatile__ ("fldenv %0" : : "m" (*&temp));
+
+      /* And raise the exception.  */
+      __asm__ __volatile__ ("fwait");
+    }
+
+  /* Last: inexact.  */
+  if ((FE_INEXACT & excepts) != 0)
+    {
+      /* There is no way to raise only the inexact flag.  Do it the
+	 hard way.  */
+      fenv_t temp;
+
+      /* Bah, we have to clear selected exceptions.  Since there is no
+	 `fldsw' instruction we have to do it the hard way.  */
+      __asm__ __volatile__ ("fnstenv %0" : "=m" (*&temp));
+
+      /* Set the relevant bits.  */
+      temp.__status_word |= FE_INEXACT;
+
+      /* Put the new data in effect.  */
+      __asm__ __volatile__ ("fldenv %0" : : "m" (*&temp));
+
+      /* And raise the exception.  */
+      __asm__ __volatile__ ("fwait");
+    }
+
+  /* Success.  */
+  return 0;
+}
+libm_hidden_def(feraiseexcept)

libm/i386/fsetexcptflg.c

@@ -0,0 +1,62 @@
+/* Set floating-point environment exception handling.
+   Copyright (C) 1997,99,2000,01, 2004 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <fenv.h>
+#include <math.h>
+#include <unistd.h>
+
+int
+fesetexceptflag (const fexcept_t *flagp, int excepts)
+{
+  fenv_t temp;
+
+  /* Get the current environment.  We have to do this since we cannot
+     separately set the status word.  */
+  __asm__ ("fnstenv %0" : "=m" (*&temp));
+
+  temp.__status_word &= ~(excepts & FE_ALL_EXCEPT);
+  temp.__status_word |= *flagp & excepts & FE_ALL_EXCEPT;
+
+  /* Store the new status word (along with the rest of the environment.
+     Possibly new exceptions are set but they won't get executed unless
+     the next floating-point instruction.  */
+  __asm__ ("fldenv %0" : : "m" (*&temp));
+
+#if 0
+  /* If the CPU supports SSE, we set the MXCSR as well.  */
+  if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0)
+    {
+      unsigned int xnew_exc;
+
+      /* Get the current MXCSR.  */
+      __asm__ ("stmxcsr %0" : "=m" (*&xnew_exc));
+
+      /* Set the relevant bits.  */
+      xnew_exc &= ~(excepts & FE_ALL_EXCEPT);
+      xnew_exc |= *flagp & excepts & FE_ALL_EXCEPT;
+
+      /* Put the new data in effect.  */
+      __asm__ ("ldmxcsr %0" : : "m" (*&xnew_exc));
+    }
+#endif
+
+  /* Success.  */
+  return 0;
+}

libm/i386/ftestexcept.c

@@ -0,0 +1,40 @@
+/* Test exception in current environment.
+   Copyright (C) 1997, 2003, 2004 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <fenv.h>
+#include <unistd.h>
+
+int
+fetestexcept (int excepts)
+{
+  int temp;
+  int xtemp = 0;
+
+  /* Get current exceptions.  */
+  __asm__ ("fnstsw %0" : "=a" (temp));
+
+#if 0
+  /* If the CPU supports SSE we test the MXCSR as well.  */
+  if ((GLRO(dl_hwcap) & HWCAP_I386_XMM) != 0)
+    __asm__ ("stmxcsr %0" : "=m" (*&xtemp));
+#endif
+
+  return (temp | xtemp) & excepts & FE_ALL_EXCEPT;
+}