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-rw-r--r--ports/sysdeps/alpha/fpu/s_ceil.c57
1 files changed, 57 insertions, 0 deletions
diff --git a/ports/sysdeps/alpha/fpu/s_ceil.c b/ports/sysdeps/alpha/fpu/s_ceil.c
new file mode 100644
index 0000000000..bbc35827f5
--- /dev/null
+++ b/ports/sysdeps/alpha/fpu/s_ceil.c
@@ -0,0 +1,57 @@
+/* Copyright (C) 1998, 2000, 2006, 2007 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Richard Henderson.
+
+   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 <math.h>
+#include <math_ldbl_opt.h>
+
+/* Use the -inf rounding mode conversion instructions to implement
+   ceil, via something akin to -floor(-x).  This is much faster than
+   playing with the fpcr to achieve +inf rounding mode.  */
+
+double
+__ceil (double x)
+{
+  if (isless (fabs (x), 9007199254740992.0))	/* 1 << DBL_MANT_DIG */
+    {
+      double tmp1, new_x;
+
+      new_x = -x;
+      __asm (
+#ifdef _IEEE_FP_INEXACT
+	     "cvttq/svim %2,%1\n\t"
+#else
+	     "cvttq/svm %2,%1\n\t"
+#endif
+	     "cvtqt/m %1,%0\n\t"
+	     : "=f"(new_x), "=&f"(tmp1)
+	     : "f"(new_x));
+
+      /* Fix up the negation we did above, as well as handling -0 properly. */
+      x = copysign(new_x, x);
+    }
+  return x;
+}
+
+weak_alias (__ceil, ceil)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__ceil, __ceill)
+weak_alias (__ceil, ceill)
+#endif
+#if LONG_DOUBLE_COMPAT(libm, GLIBC_2_0)
+compat_symbol (libm, __ceil, ceill, GLIBC_2_0);
+#endif