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-rw-r--r--sysdeps/alpha/fpu/s_ceil.c57
1 files changed, 57 insertions, 0 deletions
diff --git a/sysdeps/alpha/fpu/s_ceil.c b/sysdeps/alpha/fpu/s_ceil.c
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index 0000000000..87ce984ea3
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+++ b/sysdeps/alpha/fpu/s_ceil.c
@@ -0,0 +1,57 @@
+/* Copyright (C) 1998-2014 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