sysdeps/powerpc/fpu/fenv_private.h

   1 /* Private floating point rounding and exceptions handling. PowerPC version.
   2    Copyright (C) 2013-2024 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 POWERPC_FENV_PRIVATE_H
  20 #define POWERPC_FENV_PRIVATE_H 1
  21
  22 #include <fenv.h>
  23 #include <fenv_libc.h>
  24 #include <fpu_control.h>
  25
  26 #ifdef _ARCH_PWR8
  27 /* There is no performance advantage to non-stop mode.  */
  28 /* The odd syntax here is to innocuously reference the given variables
  29    to prevent warnings about unused variables.  */
  30 #define __TEST_AND_BEGIN_NON_STOP(old, new) do {} while ((old) * (new) * 0 != 0)
  31 #define __TEST_AND_END_NON_STOP(old, new) do {} while ((old) * (new) * 0 != 0)
  32 #else
  33 #define __TEST_AND_BEGIN_NON_STOP __TEST_AND_ENTER_NON_STOP
  34 #define __TEST_AND_END_NON_STOP __TEST_AND_EXIT_NON_STOP
  35 #endif
  36
  37 static __always_inline void
  38 libc_feholdexcept_setround_ppc (fenv_t *envp, int r)
  39 {
  40   fenv_union_t old, new;
  41
  42   old.fenv = *envp = fegetenv_register ();
  43
  44   __TEST_AND_BEGIN_NON_STOP (old.l, 0ULL);
  45
  46   /* Clear everything and set the rounding mode.  */
  47   new.l = r;
  48   fesetenv_register (new.fenv);
  49 }
  50
  51 static __always_inline unsigned long long
  52 __libc_femergeenv_ppc (const fenv_t *envp, unsigned long long old_mask,
  53         unsigned long long new_mask)
  54 {
  55   fenv_union_t old, new;
  56
  57   new.fenv = *envp;
  58   old.fenv = fegetenv_register ();
  59
  60   /* Merge bits while masking unwanted bits from new and old env.  */
  61   new.l = (old.l & old_mask) | (new.l & new_mask);
  62
  63   __TEST_AND_END_NON_STOP (old.l, new.l);
  64   __TEST_AND_BEGIN_NON_STOP (old.l, new.l);
  65
  66   /* If requesting to keep status, replace control, and merge exceptions,
  67      and exceptions haven't changed, we can just set new control instead
  68      of the whole FPSCR.  */
  69   if ((old_mask & (FPSCR_CONTROL_MASK|FPSCR_STATUS_MASK|FPSCR_EXCEPTIONS_MASK))
  70       == (FPSCR_STATUS_MASK|FPSCR_EXCEPTIONS_MASK) &&
  71       (new_mask & (FPSCR_CONTROL_MASK|FPSCR_STATUS_MASK|FPSCR_EXCEPTIONS_MASK))
  72       == (FPSCR_CONTROL_MASK|FPSCR_EXCEPTIONS_MASK) &&
  73       (old.l & FPSCR_EXCEPTIONS_MASK) == (new.l & FPSCR_EXCEPTIONS_MASK))
  74   {
  75     fesetenv_control (new.fenv);
  76   }
  77   else
  78     /* Atomically enable and raise (if appropriate) exceptions set in `new'.  */
  79     fesetenv_register (new.fenv);
  80
  81   return old.l;
  82 }
  83
  84 static __always_inline void
  85 libc_fesetenv_ppc (const fenv_t *envp)
  86 {
  87   /* Replace the entire environment.  */
  88   __libc_femergeenv_ppc (envp, 0LL, -1LL);
  89 }
  90
  91 static __always_inline void
  92 libc_feresetround_ppc (fenv_t *envp)
  93 {
  94   fenv_union_t new = { .fenv = *envp };
  95   fegetenv_and_set_rn (new.l & FPSCR_RN_MASK);
  96 }
  97
  98 static __always_inline int
  99 libc_feupdateenv_test_ppc (fenv_t *envp, int ex)
 100 {
 101   return __libc_femergeenv_ppc (envp, ~FPSCR_CONTROL_MASK,
 102                                 ~FPSCR_STATUS_MASK) & ex;
 103 }
 104
 105 static __always_inline void
 106 libc_feupdateenv_ppc (fenv_t *e)
 107 {
 108   libc_feupdateenv_test_ppc (e, 0);
 109 }
 110
 111 #define libc_feholdexceptf           libc_feholdexcept_ppc
 112 #define libc_feholdexcept            libc_feholdexcept_ppc
 113 #define libc_feholdexcept_setroundf  libc_feholdexcept_setround_ppc
 114 #define libc_feholdexcept_setround   libc_feholdexcept_setround_ppc
 115 #define libc_fetestexceptf           libc_fetestexcept_ppc
 116 #define libc_fetestexcept            libc_fetestexcept_ppc
 117 #define libc_fesetroundf             libc_fesetround_ppc
 118 #define libc_fesetround              libc_fesetround_ppc
 119 #define libc_fesetenvf               libc_fesetenv_ppc
 120 #define libc_fesetenv                libc_fesetenv_ppc
 121 #define libc_feupdateenv_testf       libc_feupdateenv_test_ppc
 122 #define libc_feupdateenv_test        libc_feupdateenv_test_ppc
 123 #define libc_feupdateenvf            libc_feupdateenv_ppc
 124 #define libc_feupdateenv             libc_feupdateenv_ppc
 125 #define libc_feholdsetroundf         libc_feholdsetround_ppc
 126 #define libc_feholdsetround          libc_feholdsetround_ppc
 127 #define libc_feresetroundf           libc_feresetround_ppc
 128 #define libc_feresetround            libc_feresetround_ppc
 129
 130
 131 /* We have support for rounding mode context.  */
 132 #define HAVE_RM_CTX 1
 133
 134 static __always_inline void
 135 libc_feholdsetround_ppc_ctx (struct rm_ctx *ctx, int r)
 136 {
 137   fenv_union_t old;
 138
 139   ctx->env = old.fenv = fegetenv_and_set_rn (r);
 140   ctx->updated_status = (r != (old.l & FPSCR_RN_MASK));
 141 }
 142
 143 static __always_inline void
 144 libc_feholdsetround_noex_ppc_ctx (struct rm_ctx *ctx, int r)
 145 {
 146   fenv_union_t old, new;
 147
 148   old.fenv = fegetenv_register ();
 149
 150   new.l = (old.l & ~(FPSCR_ENABLES_MASK|FPSCR_RN_MASK)) | r;
 151
 152   ctx->env = old.fenv;
 153   if (__glibc_unlikely (new.l != old.l))
 154     {
 155       __TEST_AND_BEGIN_NON_STOP (old.l, 0ULL);
 156       fesetenv_control (new.fenv);
 157       ctx->updated_status = true;
 158     }
 159   else
 160     ctx->updated_status = false;
 161 }
 162
 163 static __always_inline void
 164 libc_fesetenv_ppc_ctx (struct rm_ctx *ctx)
 165 {
 166   libc_fesetenv_ppc (&ctx->env);
 167 }
 168
 169 static __always_inline void
 170 libc_feupdateenv_ppc_ctx (struct rm_ctx *ctx)
 171 {
 172   if (__glibc_unlikely (ctx->updated_status))
 173     libc_feresetround_ppc (&ctx->env);
 174 }
 175
 176 static __always_inline void
 177 libc_feresetround_ppc_ctx (struct rm_ctx *ctx)
 178 {
 179   if (__glibc_unlikely (ctx->updated_status))
 180     libc_feresetround_ppc (&ctx->env);
 181 }
 182
 183 #define libc_fesetenv_ctx                libc_fesetenv_ppc_ctx
 184 #define libc_fesetenvf_ctx               libc_fesetenv_ppc_ctx
 185 #define libc_fesetenvl_ctx               libc_fesetenv_ppc_ctx
 186 #define libc_feholdsetround_ctx          libc_feholdsetround_ppc_ctx
 187 #define libc_feholdsetroundf_ctx         libc_feholdsetround_ppc_ctx
 188 #define libc_feholdsetroundl_ctx         libc_feholdsetround_ppc_ctx
 189 #define libc_feholdsetround_noex_ctx     libc_feholdsetround_noex_ppc_ctx
 190 #define libc_feholdsetround_noexf_ctx    libc_feholdsetround_noex_ppc_ctx
 191 #define libc_feholdsetround_noexl_ctx    libc_feholdsetround_noex_ppc_ctx
 192 #define libc_feresetround_ctx            libc_feresetround_ppc_ctx
 193 #define libc_feresetroundf_ctx           libc_feresetround_ppc_ctx
 194 #define libc_feresetroundl_ctx           libc_feresetround_ppc_ctx
 195 #define libc_feupdateenv_ctx             libc_feupdateenv_ppc_ctx
 196 #define libc_feupdateenvf_ctx            libc_feupdateenv_ppc_ctx
 197 #define libc_feupdateenvl_ctx            libc_feupdateenv_ppc_ctx
 198
 199 #include_next <fenv_private.h>
 200
 201 #endif