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-rw-r--r--sysdeps/alpha/Makefile4
-rw-r--r--sysdeps/alpha/fpu/fclrexcpt.c36
-rw-r--r--sysdeps/alpha/fpu/fegetenv.c37
-rw-r--r--sysdeps/alpha/fpu/fegetround.c31
-rw-r--r--sysdeps/alpha/fpu/feholdexcpt.c33
-rw-r--r--sysdeps/alpha/fpu/fenvbits.h107
-rw-r--r--sysdeps/alpha/fpu/fesetenv.c45
-rw-r--r--sysdeps/alpha/fpu/fesetround.c41
-rw-r--r--sysdeps/alpha/fpu/feupdateenv.c38
-rw-r--r--sysdeps/alpha/fpu/fgetexcptflg.c33
-rw-r--r--sysdeps/alpha/fpu/fpu_control.h46
-rw-r--r--sysdeps/alpha/fpu/fraiseexcpt.c72
-rw-r--r--sysdeps/alpha/fpu/fsetexcptflg.c36
-rw-r--r--sysdeps/alpha/fpu/ftestexcept.c32
14 files changed, 568 insertions, 23 deletions
diff --git a/sysdeps/alpha/Makefile b/sysdeps/alpha/Makefile
index 841dc980a8..5fe8e4ee7f 100644
--- a/sysdeps/alpha/Makefile
+++ b/sysdeps/alpha/Makefile
@@ -44,3 +44,7 @@ sysdep-CFLAGS += -mno-fp-regs
 endif
 
 divrem := divl divq reml remq
+
+# For now, build everything with full IEEE math support. 
+# TODO: build separate libm and libm-ieee.
+sysdep-CFLAGS += -mieee
diff --git a/sysdeps/alpha/fpu/fclrexcpt.c b/sysdeps/alpha/fpu/fclrexcpt.c
new file mode 100644
index 0000000000..7aa79af100
--- /dev/null
+++ b/sysdeps/alpha/fpu/fclrexcpt.c
@@ -0,0 +1,36 @@
+/* Clear given exceptions in current floating-point environment.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Richard Henderson <rth@tamu.edu>, 1997.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <fenv.h>
+
+void
+feclearexcept (int excepts)
+{
+  unsigned long swcr;
+
+  /* Get the current state.  */
+  swcr = __ieee_get_fp_control();
+
+  /* Clear the relevant bits.  */
+  swcr &= ~((unsigned long)excepts & FE_ALL_EXCEPT);
+
+  /* Put the new state in effect.  */
+  __ieee_set_fp_control(swcr);
+}
diff --git a/sysdeps/alpha/fpu/fegetenv.c b/sysdeps/alpha/fpu/fegetenv.c
new file mode 100644
index 0000000000..c8b705d230
--- /dev/null
+++ b/sysdeps/alpha/fpu/fegetenv.c
@@ -0,0 +1,37 @@
+/* Store current floating-point environment.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Richard Henderson <rth@tamu.edu>, 1997
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <fenv.h>
+
+void
+fegetenv (fenv_t *envp)
+{
+  unsigned long fpcr, swcr;
+
+  /* Get status from software and hardware.  Note that we don't need an
+     excb because the callsys is an implied trap barrier.  */
+  swcr = __ieee_get_fp_control();
+  __asm__ __volatile__("mf_fpcr %0" : "=f"(fpcr));
+
+  /* Merge the two bits of information.  The magic number at the end is
+     the exception enable mask.  */
+
+  *envp = (fpcr & (3UL << 58)) | (swcr & (FE_ALL_EXCEPT | 0x3e));
+}
diff --git a/sysdeps/alpha/fpu/fegetround.c b/sysdeps/alpha/fpu/fegetround.c
new file mode 100644
index 0000000000..623e2ce358
--- /dev/null
+++ b/sysdeps/alpha/fpu/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 Richard Henderson <rth@tamu.edu>, 1997
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  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)
+{
+  unsigned long fpcr;
+
+  __asm__ __volatile__("excb; mf_fpcr %0" : "=f"(fpcr));
+
+  return (fpcr >> 58) & 3;
+}
diff --git a/sysdeps/alpha/fpu/feholdexcpt.c b/sysdeps/alpha/fpu/feholdexcpt.c
new file mode 100644
index 0000000000..493d6a18eb
--- /dev/null
+++ b/sysdeps/alpha/fpu/feholdexcpt.c
@@ -0,0 +1,33 @@
+/* Store current floating-point environment and clear exceptions.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Richard Henderson <rth@tamu.edu>, 1997
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <fenv.h>
+
+int
+feholdexcept (fenv_t *envp)
+{
+  /* Save the current state.  */
+  fegetenv(envp);
+
+  /* Clear all exception status bits and exception enable bits.  */
+  __ieee_set_fp_control(0);
+
+  return 1;
+}
diff --git a/sysdeps/alpha/fpu/fenvbits.h b/sysdeps/alpha/fpu/fenvbits.h
new file mode 100644
index 0000000000..02414e4c30
--- /dev/null
+++ b/sysdeps/alpha/fpu/fenvbits.h
@@ -0,0 +1,107 @@
+/* Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Richard Henderson <rth@tamu.edu>, 1997
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+/* This file should never be included directly.  */
+
+#ifndef _FENVBITS_H
+#define _FENVBITS_H	1
+
+/* Define the bits representing the exception.
+
+   Note that these are the bit positions as defined by the OSF/1
+   ieee_{get,set}_control_word interface and not by the hardware fpcr.
+
+   See the Alpha Architecture Handbook section 4.7.7.3 for details,
+   but in summary, trap shadows mean the hardware register can acquire
+   extra exception bits so for proper IEEE support the tracking has to
+   be done in software -- in this case with kernel support.
+
+   As to why the system call interface isn't in the same format as
+   the hardware register, only those crazy folks at DEC can tell you.  */
+
+enum
+  {
+    FE_INEXACT =	1UL << 21,
+#define FE_INEXACT	FE_INEXACT
+
+    FE_UNDERFLOW =	1UL << 20,
+#define FE_UNDERFLOW	FE_UNDERFLOW
+
+    FE_OVERFLOW =	1UL << 19,
+#define FE_OVERFLOW	FE_OVERFLOW
+
+    FE_DIVBYZERO =	1UL << 18,
+#define FE_DIVBYZERO	FE_DIVBYZERO
+
+    FE_INVALID =	1UL << 17,
+#define FE_INVALID	FE_INVALID
+    
+    FE_ALL_EXCEPT =
+	(FE_INEXACT | FE_DIVBYZERO | FE_UNDERFLOW | FE_OVERFLOW | FE_INVALID)
+#define FE_ALL_EXCEPT	FE_ALL_EXCEPT 
+  };
+
+
+/* Alpha chips support all four defined rouding modes. 
+
+   Note that code must be compiled to use dynamic rounding (/d) instructions
+   to see these changes.  For gcc this is -mfp-rounding-mode=d; for DEC cc
+   this is -fprm d.  The default for both is static rounding to nearest. 
+
+   These are shifted down 58 bits from the hardware fpcr because the 
+   functions are declared to take integers.  */
+
+enum
+  {
+    FE_TOWARDSZERO =	0,
+#define FE_TOWARDSZERO	FE_TOWARDSZERO
+
+    FE_DOWNWARD = 	1,
+#define FE_DOWNWARD	FE_DOWNWARD
+
+    FE_TONEAREST =	2,
+#define FE_TONEAREST	FE_TONEAREST
+
+    FE_UPWARD =		3,
+#define FE_UPWARD	FE_UPWARD
+  };
+
+
+/* Type representing exception flags.  */
+typedef unsigned long fexcept_t;
+
+/* Type representing floating-point environment.  */
+typedef unsigned long fenv_t;
+
+/* If the default argument is used we use this value.  Note that due to
+   architecture-specified page mappings, no user-space pointer will ever
+   have its two high bits set.  Co-opt one.  */
+#define FE_DFL_ENV	((fenv_t *) 0x8800000000000000UL)
+
+#ifdef __USE_GNU
+/* Floating-point environment where none of the exceptions are masked.  */
+# define FE_NOMASK_ENV	((fenv_t *) 0x880000000000003eUL)
+#endif
+
+/* The system calls to talk to the kernel's FP code.  */
+extern unsigned long __ieee_get_fp_control(void);
+extern void __ieee_set_fp_control(unsigned long);
+
+
+#endif /* fenvbits.h */
diff --git a/sysdeps/alpha/fpu/fesetenv.c b/sysdeps/alpha/fpu/fesetenv.c
new file mode 100644
index 0000000000..3692967a5b
--- /dev/null
+++ b/sysdeps/alpha/fpu/fesetenv.c
@@ -0,0 +1,45 @@
+/* Install given floating-point environment.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Richard Henderson <rth@tamu.edu>, 1997
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <fenv.h>
+
+void
+fesetenv (const fenv_t *envp)
+{
+  unsigned long fpcr;
+  fenv_t env;
+
+  /* Magic encoding of default values: high bit set (never possible for a
+     user-space address) is not indirect.  And we don't even have to get
+     rid of it since we mask things around just below.  */
+  if ((long)envp >= 0)
+    env = *envp;
+  else
+    env = (unsigned long)envp;
+
+  /* Reset the rounding mode with the hardware fpcr.  Note that the following
+     system call is an implied trap barrier for our modification.  */
+  __asm__ __volatile__("excb; mf_fpcr %0" : "=f"(fpcr));
+  fpcr = (fpcr & ~(3UL << 58)) | (env & (3UL << 58));
+  __asm__ __volatile__("mt_fpcr %0" : : "f"(fpcr));
+
+  /* Reset the exception status and mask with the kernel's FP code.  */
+  __ieee_set_fp_control(env & (FE_ALL_EXCEPT | 0x3e));
+}
diff --git a/sysdeps/alpha/fpu/fesetround.c b/sysdeps/alpha/fpu/fesetround.c
new file mode 100644
index 0000000000..f49586cf8b
--- /dev/null
+++ b/sysdeps/alpha/fpu/fesetround.c
@@ -0,0 +1,41 @@
+/* Set current rounding direction.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Richard Henderson <rth@tamu.edu>, 1997
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <fenv.h>
+
+int
+fesetround (int round)
+{
+  unsigned long fpcr;
+
+  if (round & ~3)
+    return 0;
+
+  /* Get the current state.  */
+  __asm__ __volatile__("excb; mf_fpcr %0" : "=f"(fpcr));
+
+  /* Set the relevant bits.  */
+  fpcr = (fpcr & ~(3UL << 58)) | ((unsigned long)round << 58);
+
+  /* Put the new state in effect.  */
+  __asm__ __volatile__("mt_fpcr %0; excb" : : "f"(fpcr));
+
+  return 1;
+}
diff --git a/sysdeps/alpha/fpu/feupdateenv.c b/sysdeps/alpha/fpu/feupdateenv.c
new file mode 100644
index 0000000000..816575a134
--- /dev/null
+++ b/sysdeps/alpha/fpu/feupdateenv.c
@@ -0,0 +1,38 @@
+/* Install given floating-point environment and raise exceptions.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Richard Henderson <rth@tamu.edu>, 1997.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <fenv.h>
+
+void
+feupdateenv (const fenv_t *envp)
+{
+  unsigned long tmp;
+
+  /* Get the current exception state.  */
+  tmp = __ieee_get_fp_control();
+
+  /* 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)tmp & FE_ALL_EXCEPT);
+}
diff --git a/sysdeps/alpha/fpu/fgetexcptflg.c b/sysdeps/alpha/fpu/fgetexcptflg.c
new file mode 100644
index 0000000000..28d9e129b1
--- /dev/null
+++ b/sysdeps/alpha/fpu/fgetexcptflg.c
@@ -0,0 +1,33 @@
+/* Store current representation for exceptions.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Richard Henderson <rth@tamu.edu>, 1997.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <fenv.h>
+
+void
+fegetexceptflag (fexcept_t *flagp, int excepts)
+{
+  unsigned long tmp;
+
+  /* Get the current state.  */
+  tmp = __ieee_get_fp_control();
+
+  /* Return that portion that corresponds to the requested exceptions. */
+  *flagp = tmp & excepts & FE_ALL_EXCEPT;
+}
diff --git a/sysdeps/alpha/fpu/fpu_control.h b/sysdeps/alpha/fpu/fpu_control.h
index 219ea55f24..bcf73e857e 100644
--- a/sysdeps/alpha/fpu/fpu_control.h
+++ b/sysdeps/alpha/fpu/fpu_control.h
@@ -1,23 +1,22 @@
-/* FPU control word bits.  Alpha version.
-Copyright (C) 1996 Free Software Foundation, Inc.
-Contributed by Olaf Flebbe.
-
-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 Library General Public License as
-published by the Free Software Foundation; either version 2 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
-Library General Public License for more details.
-
-You should have received a copy of the GNU Library General Public
-License along with the GNU C Library; see the file COPYING.LIB.  If
-not, write to the Free Software Foundation, Inc., 675 Mass Ave,
-Cambridge, MA 02139, USA.  */
+/* FPU control word bits.  Alpha-maped-to-Intel version.
+   Copyright (C) 1996 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Olaf Flebbe.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
 
 #ifndef _ALPHA_FPU_CONTROL_H
 #define _ALPHA_FPU_CONTROL_H
@@ -91,11 +90,12 @@ Cambridge, MA 02139, USA.  */
        qualifier.  By setting the dynamic rounding mode to +infinity,
        one can use /d to get round to +infinity with no extra overhead
        (so long as the default isn't changed, of course...)
-     - exceptions on overflow, zero divide and NaN */
-#define _FPU_DEFAULT  0x1f72
+     - no exceptions enabled.  */
+
+#define _FPU_DEFAULT  0x137f
 
 /* IEEE:  same as above, but exceptions */
-#define _FPU_IEEE     0x1f7f
+#define _FPU_IEEE     0x137f
 
 /* Type of the control word.  */
 typedef unsigned int fpu_control_t;
diff --git a/sysdeps/alpha/fpu/fraiseexcpt.c b/sysdeps/alpha/fpu/fraiseexcpt.c
new file mode 100644
index 0000000000..6a53e55e7d
--- /dev/null
+++ b/sysdeps/alpha/fpu/fraiseexcpt.c
@@ -0,0 +1,72 @@
+/* Raise given exceptions.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Richard Henderson <rth@tamu.edu>, 1997.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  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>
+
+void
+feraiseexcept (int excepts)
+{
+  double tmp;
+
+  /* Raise exceptions represented by EXPECTS.  But we must raise only
+     one signal at a time.  It is important the if the overflow/underflow
+     exception and the inexact exception are given at the same time,
+     the overflow/underflow exception precedes the inexact exception.  */
+
+  /* We do these bits in assembly to be certain GCC doesn't optimize
+     away something important.  */
+
+  /* First: invalid exception.  */
+  if (FE_INVALID & excepts)
+    {
+      /* One example of a invalid operation is 0 * Infinity.  */
+      __asm__ __volatile__("mult/sui $f31,%1,%0; trapb"
+			   : "=f"(tmp) : "f"(HUGE_VAL));
+    }
+
+  /* Next: division by zero.  */
+  if (FE_DIVBYZERO & excepts)
+    {
+      __asm__ __volatile__("cmpteq $f31,$f31,%0; divt/sui %0,$f31,%0; trapb"
+			   : "=f"(tmp));
+    }
+
+  /* Next: overflow.  */
+  if (FE_OVERFLOW & excepts)
+    {
+      __asm__ __volatile__("mult/sui %1,%1,%0; trapb"
+			   : "=f"(tmp) : "f"(DBL_MAX));
+    }
+
+  /* Next: underflow.  */
+  if (FE_UNDERFLOW & excepts)
+    {
+      __asm__ __volatile__("divt/sui %1,%2,%0; trapb"
+			   : "=f"(tmp) : "f"(DBL_MIN), "f"(16.0));
+    }
+
+  /* Last: inexact.  */
+  if (FE_INEXACT & excepts)
+    {
+      __asm__ __volatile__("divt/sui %1,%2,%0; trapb"
+			   : "=f"(tmp) : "f"(1.0), "f"(M_PI));
+    }
+}
diff --git a/sysdeps/alpha/fpu/fsetexcptflg.c b/sysdeps/alpha/fpu/fsetexcptflg.c
new file mode 100644
index 0000000000..7e373bea6f
--- /dev/null
+++ b/sysdeps/alpha/fpu/fsetexcptflg.c
@@ -0,0 +1,36 @@
+/* Set floating-point environment exception handling.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Richard Henderson <rth@tamu.edu>, 1997.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <fenv.h>
+
+void
+fesetexceptflag (const fexcept_t *flagp, int excepts)
+{
+  unsigned long tmp;
+
+  /* Get the current exception state.  */
+  tmp = __ieee_get_fp_control();
+
+  /* Set all the bits that were called for.  */
+  tmp = tmp & ~FE_ALL_EXCEPT | *flagp & excepts & FE_ALL_EXCEPT;
+
+  /* And store it back.  */
+  __ieee_set_fp_control(tmp);
+}
diff --git a/sysdeps/alpha/fpu/ftestexcept.c b/sysdeps/alpha/fpu/ftestexcept.c
new file mode 100644
index 0000000000..9ee9dc9c55
--- /dev/null
+++ b/sysdeps/alpha/fpu/ftestexcept.c
@@ -0,0 +1,32 @@
+/* Test exception in current environment.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Richard Henderson <rth@tamu.edu>, 1997.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <fenv.h>
+
+int
+fetestexcept (int excepts)
+{
+  unsigned long tmp;
+
+  /* Get current exceptions.  */
+  tmp = __ieee_get_fp_control();
+
+  return tmp & excepts & FE_ALL_EXCEPT;
+}