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authorAndreas Schwab <schwab@linux-m68k.org>2014-02-10 20:05:01 +0100
committerAndreas Schwab <schwab@linux-m68k.org>2014-02-10 20:22:40 +0100
commit73588a7223bec40d652fd4c75f1cb4772c5d2612 (patch)
treedfc1f1965e78e62e611199d91c482d1b76ff109d /sysdeps/m68k/coldfire/fpu/fraiseexcpt.c
parent87569616d27a2c742f87b5dbcac2f2e3437fd874 (diff)
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Move m68k from ports to libc
Diffstat (limited to 'sysdeps/m68k/coldfire/fpu/fraiseexcpt.c')
-rw-r--r--sysdeps/m68k/coldfire/fpu/fraiseexcpt.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/sysdeps/m68k/coldfire/fpu/fraiseexcpt.c b/sysdeps/m68k/coldfire/fpu/fraiseexcpt.c
new file mode 100644
index 0000000000..3d75deb6ac
--- /dev/null
+++ b/sysdeps/m68k/coldfire/fpu/fraiseexcpt.c
@@ -0,0 +1,66 @@
+/* Raise given exceptions.
+   Copyright (C) 2006-2014 Free Software Foundation, Inc.
+   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 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 <float.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.
+
+     The Coldfire FPU allows an exception to be raised by asserting
+     the associated EXC bit and then executing an arbitrary arithmetic
+     instruction.  fmove.l is classified as an arithmetic instruction
+     and suffices for this purpose.
+
+     We therefore raise an exception by setting both the EXC and AEXC
+     bit associated with the exception (the former being 6 bits to the
+     left of the latter) and then loading the longword at (%sp) into an
+     FP register.  */
+
+  inline void
+  raise_one_exception (int mask)
+  {
+    if (excepts & mask)
+      {
+	int fpsr;
+	double unused;
+
+	asm volatile ("fmove%.l %/fpsr,%0" : "=d" (fpsr));
+	fpsr |= (mask << 6) | mask;
+	asm volatile ("fmove%.l %0,%/fpsr" :: "d" (fpsr));
+	asm volatile ("fmove%.l (%%sp),%0" : "=f" (unused));
+      }
+  }
+
+  raise_one_exception (FE_INVALID);
+  raise_one_exception (FE_DIVBYZERO);
+  raise_one_exception (FE_OVERFLOW);
+  raise_one_exception (FE_UNDERFLOW);
+  raise_one_exception (FE_INEXACT);
+
+  /* Success.  */
+  return 0;
+}
+libm_hidden_def (feraiseexcept)