1 /* Raise given exceptions.
2 Copyright (C) 2000-2017 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4 Contributed by Denis Joseph Barrow (djbarrow@de.ibm.com) and
5 Martin Schwidefsky (schwidefsky@de.ibm.com).
7 The GNU C Library is free software; you can redistribute it and/or
8 modify it under the terms of the GNU Lesser General Public
9 License as published by the Free Software Foundation; either
10 version 2.1 of the License, or (at your option) any later version.
12 The GNU C Library is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 Lesser General Public License for more details.
17 You should have received a copy of the GNU Lesser General Public
18 License along with the GNU C Library; if not, see
19 <http://www.gnu.org/licenses/>. */
21 #include <fenv_libc.h>
26 static __inline__
void
27 fexceptdiv (float d
, float e
)
29 __asm__
__volatile__ ("debr %0,%1" : : "f" (d
), "f" (e
) );
32 static __inline__
void
33 fexceptadd (float d
, float e
)
35 __asm__
__volatile__ ("aebr %0,%1" : : "f" (d
), "f" (e
) );
38 #ifdef HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT
39 static __inline__
void
40 fexceptround (double e
)
43 /* Load rounded from double to float with M3 = round toward 0, M4 = Suppress
44 IEEE-inexact exception.
45 In case of e=0x1p128 and the overflow-mask bit is zero, only the
46 IEEE-overflow flag is set. If overflow-mask bit is one, DXC field is set to
47 0x20 "IEEE overflow, exact".
48 In case of e=0x1p-150 and the underflow-mask bit is zero, only the
49 IEEE-underflow flag is set. If underflow-mask bit is one, DXC field is set
50 to 0x10 "IEEE underflow, exact".
51 This instruction is available with a zarch machine >= z196. */
52 __asm__
__volatile__ ("ledbra %0,5,%1,4" : "=f" (d
) : "f" (e
) );
57 __feraiseexcept (int excepts
)
59 /* Raise exceptions represented by EXPECTS. But we must raise only
60 one signal at a time. It is important that if the overflow/underflow
61 exception and the inexact exception are given at the same time,
62 the overflow/underflow exception follows the inexact exception. */
64 /* First: invalid exception. */
65 if (FE_INVALID
& excepts
)
66 fexceptdiv (0.0, 0.0);
68 /* Next: division by zero. */
69 if (FE_DIVBYZERO
& excepts
)
70 fexceptdiv (1.0, 0.0);
73 if (FE_OVERFLOW
& excepts
)
75 #ifdef HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT
76 fexceptround (0x1p
128);
78 /* If overflow-mask bit is zero, both IEEE-overflow and IEEE-inexact flags
79 are set. If overflow-mask bit is one, DXC field is set to 0x2C "IEEE
80 overflow, inexact and incremented". */
81 fexceptadd (FLT_MAX
, 1.0e32
);
85 /* Next: underflow. */
86 if (FE_UNDERFLOW
& excepts
)
88 #ifdef HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT
89 fexceptround (0x1p
-150);
91 /* If underflow-mask bit is zero, both IEEE-underflow and IEEE-inexact
92 flags are set. If underflow-mask bit is one, DXC field is set to 0x1C
93 "IEEE underflow, inexact and incremented". */
94 fexceptdiv (FLT_MIN
, 3.0);
99 if (FE_INEXACT
& excepts
)
100 fexceptdiv (2.0, 3.0);
105 libm_hidden_def (__feraiseexcept
)
106 weak_alias (__feraiseexcept
, feraiseexcept
)
107 libm_hidden_weak (feraiseexcept
)