| /* Raise given exceptions. |
| Copyright (C) 2000-2018 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Denis Joseph Barrow (djbarrow@de.ibm.com) and |
| Martin Schwidefsky (schwidefsky@de.ibm.com). |
| |
| 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 <fenv_libc.h> |
| #include <float.h> |
| #include <math.h> |
| |
| |
| static __inline__ void |
| fexceptdiv (float d, float e) |
| { |
| __asm__ __volatile__ ("debr %0,%1" : : "f" (d), "f" (e) ); |
| } |
| |
| static __inline__ void |
| fexceptadd (float d, float e) |
| { |
| __asm__ __volatile__ ("aebr %0,%1" : : "f" (d), "f" (e) ); |
| } |
| |
| #ifdef HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT |
| static __inline__ void |
| fexceptround (double e) |
| { |
| float d; |
| /* Load rounded from double to float with M3 = round toward 0, M4 = Suppress |
| IEEE-inexact exception. |
| In case of e=0x1p128 and the overflow-mask bit is zero, only the |
| IEEE-overflow flag is set. If overflow-mask bit is one, DXC field is set to |
| 0x20 "IEEE overflow, exact". |
| In case of e=0x1p-150 and the underflow-mask bit is zero, only the |
| IEEE-underflow flag is set. If underflow-mask bit is one, DXC field is set |
| to 0x10 "IEEE underflow, exact". |
| This instruction is available with a zarch machine >= z196. */ |
| __asm__ __volatile__ ("ledbra %0,5,%1,4" : "=f" (d) : "f" (e) ); |
| } |
| #endif |
| |
| int |
| __feraiseexcept (int excepts) |
| { |
| /* 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. */ |
| |
| /* First: invalid exception. */ |
| if (FE_INVALID & excepts) |
| fexceptdiv (0.0, 0.0); |
| |
| /* Next: division by zero. */ |
| if (FE_DIVBYZERO & excepts) |
| fexceptdiv (1.0, 0.0); |
| |
| /* Next: overflow. */ |
| if (FE_OVERFLOW & excepts) |
| { |
| #ifdef HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT |
| fexceptround (0x1p128); |
| #else |
| /* If overflow-mask bit is zero, both IEEE-overflow and IEEE-inexact flags |
| are set. If overflow-mask bit is one, DXC field is set to 0x2C "IEEE |
| overflow, inexact and incremented". */ |
| fexceptadd (FLT_MAX, 1.0e32); |
| #endif |
| } |
| |
| /* Next: underflow. */ |
| if (FE_UNDERFLOW & excepts) |
| { |
| #ifdef HAVE_S390_MIN_Z196_ZARCH_ASM_SUPPORT |
| fexceptround (0x1p-150); |
| #else |
| /* If underflow-mask bit is zero, both IEEE-underflow and IEEE-inexact |
| flags are set. If underflow-mask bit is one, DXC field is set to 0x1C |
| "IEEE underflow, inexact and incremented". */ |
| fexceptdiv (FLT_MIN, 3.0); |
| #endif |
| } |
| |
| /* Last: inexact. */ |
| if (FE_INEXACT & excepts) |
| fexceptdiv (2.0, 3.0); |
| |
| /* Success. */ |
| return 0; |
| } |
| libm_hidden_def (__feraiseexcept) |
| weak_alias (__feraiseexcept, feraiseexcept) |
| libm_hidden_weak (feraiseexcept) |