Linux/HPPA specific feraiseexcept implementation.

2025-01-24 12:25:35 +08:00 · 2000-10-15 03:36:03 +00:00 · 2000-10-15 03:36:03 +00:00 · 84e1099f78
commit 84e1099f78
parent 9bb9060790
1 changed files with 89 additions and 0 deletions
--- a/sysdeps/hppa/fpu/fraiseexcpt.c
+++ b/sysdeps/hppa/fpu/fraiseexcpt.c
@ -0,0 +1,89 @@
+/* Raise given exceptions.
+   Copyright (C) 1997, 1999, 2000 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by David Huggins-Daines <dhd@debian.org>
+
+   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>
+
+int
+feraiseexcept (int excepts)
+{
+  /* Raise exceptions represented by EXCEPTS.  But we must raise only one
+     signal at a time.  It is important that if the overflow/underflow
+     exception and the divide by zero exception are given at the same
+     time, the overflow/underflow exception follows the divide by zero
+     exception.  */
+
+  /* We do these bits in assembly to be certain GCC doesn't optimize
+     away something important, and so we can force delayed traps to
+     occur.  */
+
+  /* FIXME: These all need verification! */
+
+  /* First: invalid exception.  */
+  if (excepts & FE_INVALID)
+    {
+      /* One example of a invalid operation is 0 * Infinity.  */
+      double d = HUGE_VAL;
+      __asm__ __volatile__ ("fmpy,dbl %1,%%fr0,%0\n\t"
+			    /* FIXME: is this a proper trap barrier? */
+			    "fcpy,dbl %%fr0,%%fr0" : "=f" (d) : "0" (d));
+    }
+
+  /* Next: division by zero.  */
+  if (excepts & FE_DIVBYZERO)
+    {
+      double d = 1.0;
+      __asm__ __volatile__ ("fdiv,dbl %1,%%fr0,%0\n\t"
+			    "fcpy,dbl %%fr0,%%fr0" : "=f" (d) : "0" (d));
+    }
+
+  /* Next: overflow.  */
+  /* FIXME: Compare with IA-64 - do we have the same problem? */
+  if (excepts & FE_OVERFLOW)
+    {
+      double d = DBL_MAX;
+
+      __asm__ __volatile__ ("fmpy,dbl %1,%1,%0\n\t"
+			    "fcpy,dbl %%fr0,%%fr0" : "=f" (d) : "0" (d));
+    }
+
+  /* Next: underflow.  */
+  if (excepts & FE_UNDERFLOW)
+    {
+      double d = DBL_MIN;
+      double e = 69.69;
+
+      __asm__ __volatile__ ("fdiv,dbl %1,%2,%0\n\t"
+			    "fcpy,dbl %%fr0,%%fr0" : "=f" (d) : "0" (d), "f" (e));
+    }
+
+  /* Last: inexact.  */
+  if (excepts & FE_INEXACT)
+    {
+      double d = 1.0;
+      double e = M_PI;
+
+      __asm__ __volatile__ ("fdiv,dbl %1,%2,%0\n\t"
+			    "fcpy,dbl %%fr0,%%fr0" : "=f" (d) : "0" (d), "f" (e));
+    }
+
+  /* Success.  */
+  return 0;
+}