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-rw-r--r--sysdeps/s390/fpu/s_lrint.c55
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diff --git a/sysdeps/s390/fpu/s_lrint.c b/sysdeps/s390/fpu/s_lrint.c
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+/* lrint() - 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-double.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 "cgdbra"
+# else
+# define INSN "cfdbra"
+# endif
+
+long int
+__lrint (double x)
+{
+ long int y;
+ /* The z196 zarch "convert to fixed" (cgdbra) instruction is rounding
+ according to current rounding mode (M3-field: 0).
+ First convert x with suppressed inexact exception and check if the
+ resulting value is beyond the target limits (indicated by cc=3;
+ Note: a nan is also indicated by cc=3).
+ If the resulting value is within the target limits, redo
+ without suppressing the inexact exception. */
+ __asm__ (INSN " %0,0,%1,4 \n\t"
+ "jo 1f \n\t"
+ INSN " %0,0,%1,0 \n\t"
+ "1:"
+ : "=&d" (y) : "f" (x) : "cc");
+ return y;
+}
+libm_alias_double (__lrint, lrint)
+
+#else
+# include <sysdeps/ieee754/dbl-64/s_lrint.c>
+#endif