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+/* Raise given exceptions.
+ Copyright (C) 1997-2025 Free Software Foundation, Inc.
+
+ 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
+ <https://www.gnu.org/licenses/>. */
+
+#include <fenv.h>
+#include <float.h>
+#include <math.h>
+
+int
+feraiseexcept (int excepts)
+{
+#if defined(__mcffpu__)
+
+ /* 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);
+
+#else
+ /* 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. */
+
+ /* First: invalid exception. */
+ if (excepts & FE_INVALID)
+ {
+ /* One example of an invalid operation is 0 * Infinity. */
+ double d = HUGE_VAL;
+ __asm__ __volatile__ ("fmul%.s %#0r0,%0; fnop" : "=f" (d) : "0" (d));
+ }
+
+ /* Next: division by zero. */
+ if (excepts & FE_DIVBYZERO)
+ {
+ double d = 1.0;
+ __asm__ __volatile__ ("fdiv%.s %#0r0,%0; fnop" : "=f" (d) : "0" (d));
+ }
+
+ /* Next: overflow. */
+ if (excepts & FE_OVERFLOW)
+ {
+ long double d = LDBL_MAX;
+
+ __asm__ __volatile__ ("fmul%.x %0,%0; fnop" : "=f" (d) : "0" (d));
+ }
+
+ /* Next: underflow. */
+ if (excepts & FE_UNDERFLOW)
+ {
+ long double d = -LDBL_MAX;
+
+ __asm__ __volatile__ ("fetox%.x %0; fnop" : "=f" (d) : "0" (d));
+ }
+
+ /* Last: inexact. */
+ if (excepts & FE_INEXACT)
+ {
+ long double d = 1.0;
+ __asm__ __volatile__ ("fdiv%.s %#0r3,%0; fnop" : "=f" (d) : "0" (d));
+ }
+
+#endif
+ /* Success. */
+ return 0;
+}