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-rw-r--r--REORG.TODO/sysdeps/alpha/fpu/s_ceilf.c53
1 files changed, 53 insertions, 0 deletions
diff --git a/REORG.TODO/sysdeps/alpha/fpu/s_ceilf.c b/REORG.TODO/sysdeps/alpha/fpu/s_ceilf.c
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index 0000000000..8c76c65d7f
--- /dev/null
+++ b/REORG.TODO/sysdeps/alpha/fpu/s_ceilf.c
@@ -0,0 +1,53 @@
+/* Copyright (C) 1998-2017 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>
+
+/* 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.  */
+
+float
+__ceilf (float x)
+{
+  if (isnanf (x))
+    return x + x;
+
+  if (isless (fabsf (x), 16777216.0f))	/* 1 << FLT_MANT_DIG */
+    {
+      /* Note that Alpha S_Floating is stored in registers in a
+	 restricted T_Floating format, so we don't even need to
+	 convert back to S_Floating in the end.  The initial
+	 conversion to T_Floating is needed to handle denormals.  */
+
+      float tmp1, tmp2, new_x;
+
+      new_x = -x;
+      __asm ("cvtst/s %3,%2\n\t"
+	     "cvttq/svm %2,%1\n\t"
+	     "cvtqt/m %1,%0\n\t"
+	     : "=f"(new_x), "=&f"(tmp1), "=&f"(tmp2)
+	     : "f"(new_x));
+
+      /* Fix up the negation we did above, as well as handling -0 properly. */
+      x = copysignf(new_x, x);
+    }
+  return x;
+}
+
+weak_alias (__ceilf, ceilf)