mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-30 00:31:08 +00:00
108 lines
4.2 KiB
C
108 lines
4.2 KiB
C
/* Raise given exceptions.
|
|
Copyright (C) 2004-2017 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
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <fpu_control.h>
|
|
#include <fenv.h>
|
|
#include <float.h>
|
|
#include <arm-features.h>
|
|
|
|
|
|
int
|
|
__feraiseexcept (int excepts)
|
|
{
|
|
/* Fail if a VFP unit isn't present unless nothing needs to be done. */
|
|
if (!ARM_HAVE_VFP)
|
|
return (excepts != 0);
|
|
else
|
|
{
|
|
fpu_control_t fpscr;
|
|
const float fp_zero = 0.0, fp_one = 1.0, fp_max = FLT_MAX,
|
|
fp_min = FLT_MIN, fp_1e32 = 1.0e32f, fp_two = 2.0,
|
|
fp_three = 3.0;
|
|
|
|
/* Raise exceptions represented by EXPECTS. But we must raise only
|
|
one signal at a time. It is important that if the overflow/underflow
|
|
exception and the inexact exception are given at the same time,
|
|
the overflow/underflow exception follows the inexact exception. After
|
|
each exception we read from the fpscr, to force the exception to be
|
|
raised immediately. */
|
|
|
|
/* There are additional complications because this file may be compiled
|
|
without VFP support enabled, and we also can't assume that the
|
|
assembler has VFP instructions enabled. To get around this we use the
|
|
generic coprocessor mnemonics and avoid asking GCC to put float values
|
|
in VFP registers. */
|
|
|
|
/* First: invalid exception. */
|
|
if (FE_INVALID & excepts)
|
|
__asm__ __volatile__ (
|
|
"ldc p10, cr0, %1\n\t" /* flds s0, %1 */
|
|
"cdp p10, 8, cr0, cr0, cr0, 0\n\t" /* fdivs s0, s0, s0 */
|
|
"mrc p10, 7, %0, cr1, cr0, 0" : "=r" (fpscr) /* fmrx %0, fpscr */
|
|
: "m" (fp_zero)
|
|
: "s0");
|
|
|
|
/* Next: division by zero. */
|
|
if (FE_DIVBYZERO & excepts)
|
|
__asm__ __volatile__ (
|
|
"ldc p10, cr0, %1\n\t" /* flds s0, %1 */
|
|
"ldcl p10, cr0, %2\n\t" /* flds s1, %2 */
|
|
"cdp p10, 8, cr0, cr0, cr0, 1\n\t" /* fdivs s0, s0, s1 */
|
|
"mrc p10, 7, %0, cr1, cr0, 0" : "=r" (fpscr) /* fmrx %0, fpscr */
|
|
: "m" (fp_one), "m" (fp_zero)
|
|
: "s0", "s1");
|
|
|
|
/* Next: overflow. */
|
|
if (FE_OVERFLOW & excepts)
|
|
/* There's no way to raise overflow without also raising inexact. */
|
|
__asm__ __volatile__ (
|
|
"ldc p10, cr0, %1\n\t" /* flds s0, %1 */
|
|
"ldcl p10, cr0, %2\n\t" /* flds s1, %2 */
|
|
"cdp p10, 3, cr0, cr0, cr0, 1\n\t" /* fadds s0, s0, s1 */
|
|
"mrc p10, 7, %0, cr1, cr0, 0" : "=r" (fpscr) /* fmrx %0, fpscr */
|
|
: "m" (fp_max), "m" (fp_1e32)
|
|
: "s0", "s1");
|
|
|
|
/* Next: underflow. */
|
|
if (FE_UNDERFLOW & excepts)
|
|
__asm__ __volatile__ (
|
|
"ldc p10, cr0, %1\n\t" /* flds s0, %1 */
|
|
"ldcl p10, cr0, %2\n\t" /* flds s1, %2 */
|
|
"cdp p10, 8, cr0, cr0, cr0, 1\n\t" /* fdivs s0, s0, s1 */
|
|
"mrc p10, 7, %0, cr1, cr0, 0" : "=r" (fpscr) /* fmrx %0, fpscr */
|
|
: "m" (fp_min), "m" (fp_three)
|
|
: "s0", "s1");
|
|
|
|
/* Last: inexact. */
|
|
if (FE_INEXACT & excepts)
|
|
__asm__ __volatile__ (
|
|
"ldc p10, cr0, %1\n\t" /* flds s0, %1 */
|
|
"ldcl p10, cr0, %2\n\t" /* flds s1, %2 */
|
|
"cdp p10, 8, cr0, cr0, cr0, 1\n\t" /* fdivs s0, s0, s1 */
|
|
"mrc p10, 7, %0, cr1, cr0, 0" : "=r" (fpscr) /* fmrx %0, fpscr */
|
|
: "m" (fp_two), "m" (fp_three)
|
|
: "s0", "s1");
|
|
|
|
/* Success. */
|
|
return 0;
|
|
}
|
|
}
|
|
libm_hidden_def (__feraiseexcept)
|
|
weak_alias (__feraiseexcept, feraiseexcept)
|
|
libm_hidden_weak (feraiseexcept)
|