sysdeps/loongarch/math_private.h

   1 /* Internal math stuff.
   2    Copyright (C) 2022-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #ifndef LOONGARCH_MATH_PRIVATE_H
  20 #define LOONGARCH_MATH_PRIVATE_H 1
  21
  22 /* Inline functions to speed up the math library implementation.  The
  23    default versions of these routines are in generic/math_private.h
  24    and call fesetround, feholdexcept, etc.  These routines use inlined
  25    code instead.  */
  26
  27 #ifdef __loongarch_hard_float
  28
  29 #include <fenv.h>
  30 #include <fenv_libc.h>
  31 #include <fpu_control.h>
  32
  33 #define _FPU_MASK_ALL \
  34   (_FPU_MASK_V | _FPU_MASK_Z | _FPU_MASK_O | _FPU_MASK_U | _FPU_MASK_I \
  35    | FE_ALL_EXCEPT)
  36
  37 static __always_inline void
  38 libc_feholdexcept_loongarch (fenv_t *envp)
  39 {
  40   fpu_control_t cw;
  41
  42   /* Save the current state.  */
  43   _FPU_GETCW (cw);
  44   envp->__fp_control_register = cw;
  45
  46   /* Clear all exception enable bits and flags.  */
  47   cw &= ~(_FPU_MASK_ALL);
  48   _FPU_SETCW (cw);
  49 }
  50 #define libc_feholdexcept libc_feholdexcept_loongarch
  51 #define libc_feholdexceptf libc_feholdexcept_loongarch
  52 #define libc_feholdexceptl libc_feholdexcept_loongarch
  53
  54 static __always_inline void
  55 libc_fesetround_loongarch (int round)
  56 {
  57   fpu_control_t cw;
  58
  59   /* Get current state.  */
  60   _FPU_GETCW (cw);
  61
  62   /* Set rounding bits.  */
  63   cw &= ~_FPU_RC_MASK;
  64   cw |= round;
  65
  66   /* Set new state.  */
  67   _FPU_SETCW (cw);
  68 }
  69 #define libc_fesetround libc_fesetround_loongarch
  70 #define libc_fesetroundf libc_fesetround_loongarch
  71 #define libc_fesetroundl libc_fesetround_loongarch
  72
  73 static __always_inline void
  74 libc_feholdexcept_setround_loongarch (fenv_t *envp, int round)
  75 {
  76   fpu_control_t cw;
  77
  78   /* Save the current state.  */
  79   _FPU_GETCW (cw);
  80   envp->__fp_control_register = cw;
  81
  82   /* Clear all exception enable bits and flags.  */
  83   cw &= ~(_FPU_MASK_ALL);
  84
  85   /* Set rounding bits.  */
  86   cw &= ~_FPU_RC_MASK;
  87   cw |= round;
  88
  89   /* Set new state.  */
  90   _FPU_SETCW (cw);
  91 }
  92 #define libc_feholdexcept_setround libc_feholdexcept_setround_loongarch
  93 #define libc_feholdexcept_setroundf libc_feholdexcept_setround_loongarch
  94 #define libc_feholdexcept_setroundl libc_feholdexcept_setround_loongarch
  95
  96 #define libc_feholdsetround libc_feholdexcept_setround_loongarch
  97 #define libc_feholdsetroundf libc_feholdexcept_setround_loongarch
  98 #define libc_feholdsetroundl libc_feholdexcept_setround_loongarch
  99
 100 static __always_inline void
 101 libc_fesetenv_loongarch (fenv_t *envp)
 102 {
 103   fpu_control_t cw __attribute__ ((unused));
 104
 105   /* Read current state to flush fpu pipeline.  */
 106   _FPU_GETCW (cw);
 107
 108   _FPU_SETCW (envp->__fp_control_register);
 109 }
 110 #define libc_fesetenv libc_fesetenv_loongarch
 111 #define libc_fesetenvf libc_fesetenv_loongarch
 112 #define libc_fesetenvl libc_fesetenv_loongarch
 113
 114 static __always_inline int
 115 libc_feupdateenv_test_loongarch (fenv_t *envp, int excepts)
 116 {
 117   /* int ret = fetestexcept (excepts); feupdateenv (envp); return ret; */
 118   int cw, temp;
 119
 120   /* Get current control word.  */
 121   _FPU_GETCW (cw);
 122
 123   /* Set flag bits (which are accumulative), and *also* set the
 124      cause bits.  The setting of the cause bits is what actually causes
 125      the hardware to generate the exception, if the corresponding enable
 126      bit is set as well.  */
 127   temp = cw & FE_ALL_EXCEPT;
 128   temp |= envp->__fp_control_register | (temp << CAUSE_SHIFT);
 129
 130   /* Set new state.  */
 131   _FPU_SETCW (temp);
 132
 133   return cw & excepts & FE_ALL_EXCEPT;
 134 }
 135 #define libc_feupdateenv_test libc_feupdateenv_test_loongarch
 136 #define libc_feupdateenv_testf libc_feupdateenv_test_loongarch
 137 #define libc_feupdateenv_testl libc_feupdateenv_test_loongarch
 138
 139 static __always_inline void
 140 libc_feupdateenv_loongarch (fenv_t *envp)
 141 {
 142   libc_feupdateenv_test_loongarch (envp, 0);
 143 }
 144 #define libc_feupdateenv libc_feupdateenv_loongarch
 145 #define libc_feupdateenvf libc_feupdateenv_loongarch
 146 #define libc_feupdateenvl libc_feupdateenv_loongarch
 147
 148 #define libc_feresetround libc_feupdateenv_loongarch
 149 #define libc_feresetroundf libc_feupdateenv_loongarch
 150 #define libc_feresetroundl libc_feupdateenv_loongarch
 151
 152 static __always_inline int
 153 libc_fetestexcept_loongarch (int excepts)
 154 {
 155   int cw;
 156
 157   /* Get current control word.  */
 158   _FPU_GETCW (cw);
 159
 160   return cw & excepts & FE_ALL_EXCEPT;
 161 }
 162 #define libc_fetestexcept libc_fetestexcept_loongarch
 163 #define libc_fetestexceptf libc_fetestexcept_loongarch
 164 #define libc_fetestexceptl libc_fetestexcept_loongarch
 165
 166 /*  Enable support for rounding mode context.  */
 167 #define HAVE_RM_CTX 1
 168
 169 static __always_inline void
 170 libc_feholdexcept_setround_loongarch_ctx (struct rm_ctx *ctx, int round)
 171 {
 172   fpu_control_t old, new;
 173
 174   /* Save the current state.  */
 175   _FPU_GETCW (old);
 176   ctx->env.__fp_control_register = old;
 177
 178   /* Clear all exception enable bits and flags.  */
 179   new = old & ~(_FPU_MASK_ALL);
 180
 181   /* Set rounding bits.  */
 182   new = (new & ~_FPU_RC_MASK) | round;
 183
 184   if (__glibc_unlikely (new != old))
 185     {
 186       _FPU_SETCW (new);
 187       ctx->updated_status = true;
 188     }
 189   else
 190     ctx->updated_status = false;
 191 }
 192 #define libc_feholdexcept_setround_ctx libc_feholdexcept_setround_loongarch_ctx
 193 #define libc_feholdexcept_setroundf_ctx \
 194   libc_feholdexcept_setround_loongarch_ctx
 195 #define libc_feholdexcept_setroundl_ctx \
 196   libc_feholdexcept_setround_loongarch_ctx
 197
 198 static __always_inline void
 199 libc_fesetenv_loongarch_ctx (struct rm_ctx *ctx)
 200 {
 201   libc_fesetenv_loongarch (&ctx->env);
 202 }
 203 #define libc_fesetenv_ctx libc_fesetenv_loongarch_ctx
 204 #define libc_fesetenvf_ctx libc_fesetenv_loongarch_ctx
 205 #define libc_fesetenvl_ctx libc_fesetenv_loongarch_ctx
 206
 207 static __always_inline void
 208 libc_feupdateenv_loongarch_ctx (struct rm_ctx *ctx)
 209 {
 210   if (__glibc_unlikely (ctx->updated_status))
 211     libc_feupdateenv_test_loongarch (&ctx->env, 0);
 212 }
 213 #define libc_feupdateenv_ctx libc_feupdateenv_loongarch_ctx
 214 #define libc_feupdateenvf_ctx libc_feupdateenv_loongarch_ctx
 215 #define libc_feupdateenvl_ctx libc_feupdateenv_loongarch_ctx
 216 #define libc_feresetround_ctx libc_feupdateenv_loongarch_ctx
 217 #define libc_feresetroundf_ctx libc_feupdateenv_loongarch_ctx
 218 #define libc_feresetroundl_ctx libc_feupdateenv_loongarch_ctx
 219
 220 static __always_inline void
 221 libc_feholdsetround_loongarch_ctx (struct rm_ctx *ctx, int round)
 222 {
 223   fpu_control_t old, new;
 224
 225   /* Save the current state.  */
 226   _FPU_GETCW (old);
 227   ctx->env.__fp_control_register = old;
 228
 229   /* Set rounding bits.  */
 230   new = (old & ~_FPU_RC_MASK) | round;
 231
 232   if (__glibc_unlikely (new != old))
 233     {
 234       _FPU_SETCW (new);
 235       ctx->updated_status = true;
 236     }
 237   else
 238     ctx->updated_status = false;
 239 }
 240 #define libc_feholdsetround_ctx libc_feholdsetround_loongarch_ctx
 241 #define libc_feholdsetroundf_ctx libc_feholdsetround_loongarch_ctx
 242 #define libc_feholdsetroundl_ctx libc_feholdsetround_loongarch_ctx
 243
 244 #endif
 245
 246 #include_next <math_private.h>
 247
 248 #endif