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-rw-r--r--sysdeps/s390/fpu/s_lroundf.c47
1 files changed, 47 insertions, 0 deletions
diff --git a/sysdeps/s390/fpu/s_lroundf.c b/sysdeps/s390/fpu/s_lroundf.c
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+++ b/sysdeps/s390/fpu/s_lroundf.c
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+/* lroundf() - S390 version.
+   Copyright (C) 2019 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
+   <https://www.gnu.org/licenses/>.  */
+
+#ifdef HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT
+# include <math.h>
+# include <libm-alias-float.h>
+
+/* The sizeof (long int) differs between s390x (8byte) and s390 (4byte).
+   Thus we need different instructions as the target size is encoded there.
+   Note: On s390 this instruction is only used if build with -mzarch.  */
+# ifdef __s390x__
+#  define INSN "cgebra"
+# else
+#  define INSN "cfebra"
+# endif
+
+long int
+__lroundf (float x)
+{
+  long int y;
+  /* The z196 zarch "convert to fixed" (cgebra) instruction is rounding
+     x to the nearest integer with "ties away from 0" rounding mode
+     (M3-field: 1) where inexact exceptions are suppressed (M4-field: 4).  */
+  __asm__ (INSN " %0,1,%1,4" : "=d" (y) : "f" (x) : "cc");
+  return y;
+}
+libm_alias_float (__lround, lround)
+
+#else
+# include <sysdeps/ieee754/flt-32/s_lroundf.c>
+#endif