glibc/sysdeps/s390/fpu/math_private.h
Stefan Liebler 2763d3145a S390: Implement roundtoint and converttoint and define TOINT_INTRINSICS.
This patch implements roundtoint and convertoint for s390
by using the load-fp-integer and convert-to-fixed instructions.
Both functions are using "round to nearest with ties away from zero"
rounding mode and do not raise inexact exceptions.
2019-12-11 15:12:25 +01:00

54 lines
1.7 KiB
C

/* Configure optimized libm functions. 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/>. */
#ifndef S390_MATH_PRIVATE_H
#define S390_MATH_PRIVATE_H 1
#include <stdint.h>
#include <math.h>
#ifdef HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT
# define TOINT_INTRINSICS 1
static inline double_t
roundtoint (double_t x)
{
double_t y;
/* The z196 zarch "load fp integer" (fidbra) instruction is rounding
x to the nearest integer with ties away from zero (M3-field: 1)
where inexact exceptions are suppressed (M4-field: 4). */
__asm__ ("fidbra %0,1,%1,4" : "=f" (y) : "f" (x));
return y;
}
static inline int32_t
converttoint (double_t x)
{
int32_t y;
/* The z196 zarch "convert to fixed" (cfdbra) instruction is rounding
x to the nearest integer with ties away from zero (M3-field: 1)
where inexact exceptions are suppressed (M4-field: 4). */
__asm__ ("cfdbra %0,1,%1,4" : "=d" (y) : "f" (x) : "cc");
return y;
}
#endif
#include_next <math_private.h>
#endif